1e5dd7070Spatrick //===--- SemaStmt.cpp - Semantic Analysis for Statements ------------------===//
2e5dd7070Spatrick //
3e5dd7070Spatrick // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4e5dd7070Spatrick // See https://llvm.org/LICENSE.txt for license information.
5e5dd7070Spatrick // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6e5dd7070Spatrick //
7e5dd7070Spatrick //===----------------------------------------------------------------------===//
8e5dd7070Spatrick //
9e5dd7070Spatrick // This file implements semantic analysis for statements.
10e5dd7070Spatrick //
11e5dd7070Spatrick //===----------------------------------------------------------------------===//
12e5dd7070Spatrick
13e5dd7070Spatrick #include "clang/AST/ASTContext.h"
14e5dd7070Spatrick #include "clang/AST/ASTDiagnostic.h"
15e5dd7070Spatrick #include "clang/AST/ASTLambda.h"
16e5dd7070Spatrick #include "clang/AST/CXXInheritance.h"
17a9ac8606Spatrick #include "clang/AST/CharUnits.h"
18e5dd7070Spatrick #include "clang/AST/DeclObjC.h"
19e5dd7070Spatrick #include "clang/AST/EvaluatedExprVisitor.h"
20e5dd7070Spatrick #include "clang/AST/ExprCXX.h"
21e5dd7070Spatrick #include "clang/AST/ExprObjC.h"
22a9ac8606Spatrick #include "clang/AST/IgnoreExpr.h"
23e5dd7070Spatrick #include "clang/AST/RecursiveASTVisitor.h"
24e5dd7070Spatrick #include "clang/AST/StmtCXX.h"
25e5dd7070Spatrick #include "clang/AST/StmtObjC.h"
26e5dd7070Spatrick #include "clang/AST/TypeLoc.h"
27e5dd7070Spatrick #include "clang/AST/TypeOrdering.h"
28e5dd7070Spatrick #include "clang/Basic/TargetInfo.h"
29e5dd7070Spatrick #include "clang/Lex/Preprocessor.h"
30e5dd7070Spatrick #include "clang/Sema/Initialization.h"
31e5dd7070Spatrick #include "clang/Sema/Lookup.h"
32a9ac8606Spatrick #include "clang/Sema/Ownership.h"
33e5dd7070Spatrick #include "clang/Sema/Scope.h"
34e5dd7070Spatrick #include "clang/Sema/ScopeInfo.h"
35a9ac8606Spatrick #include "clang/Sema/SemaInternal.h"
36e5dd7070Spatrick #include "llvm/ADT/ArrayRef.h"
37e5dd7070Spatrick #include "llvm/ADT/DenseMap.h"
38e5dd7070Spatrick #include "llvm/ADT/STLExtras.h"
39e5dd7070Spatrick #include "llvm/ADT/SmallPtrSet.h"
40e5dd7070Spatrick #include "llvm/ADT/SmallString.h"
41e5dd7070Spatrick #include "llvm/ADT/SmallVector.h"
42e5dd7070Spatrick
43e5dd7070Spatrick using namespace clang;
44e5dd7070Spatrick using namespace sema;
45e5dd7070Spatrick
ActOnExprStmt(ExprResult FE,bool DiscardedValue)46e5dd7070Spatrick StmtResult Sema::ActOnExprStmt(ExprResult FE, bool DiscardedValue) {
47e5dd7070Spatrick if (FE.isInvalid())
48e5dd7070Spatrick return StmtError();
49e5dd7070Spatrick
50e5dd7070Spatrick FE = ActOnFinishFullExpr(FE.get(), FE.get()->getExprLoc(), DiscardedValue);
51e5dd7070Spatrick if (FE.isInvalid())
52e5dd7070Spatrick return StmtError();
53e5dd7070Spatrick
54e5dd7070Spatrick // C99 6.8.3p2: The expression in an expression statement is evaluated as a
55e5dd7070Spatrick // void expression for its side effects. Conversion to void allows any
56e5dd7070Spatrick // operand, even incomplete types.
57e5dd7070Spatrick
58e5dd7070Spatrick // Same thing in for stmt first clause (when expr) and third clause.
59e5dd7070Spatrick return StmtResult(FE.getAs<Stmt>());
60e5dd7070Spatrick }
61e5dd7070Spatrick
62e5dd7070Spatrick
ActOnExprStmtError()63e5dd7070Spatrick StmtResult Sema::ActOnExprStmtError() {
64e5dd7070Spatrick DiscardCleanupsInEvaluationContext();
65e5dd7070Spatrick return StmtError();
66e5dd7070Spatrick }
67e5dd7070Spatrick
ActOnNullStmt(SourceLocation SemiLoc,bool HasLeadingEmptyMacro)68e5dd7070Spatrick StmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc,
69e5dd7070Spatrick bool HasLeadingEmptyMacro) {
70e5dd7070Spatrick return new (Context) NullStmt(SemiLoc, HasLeadingEmptyMacro);
71e5dd7070Spatrick }
72e5dd7070Spatrick
ActOnDeclStmt(DeclGroupPtrTy dg,SourceLocation StartLoc,SourceLocation EndLoc)73e5dd7070Spatrick StmtResult Sema::ActOnDeclStmt(DeclGroupPtrTy dg, SourceLocation StartLoc,
74e5dd7070Spatrick SourceLocation EndLoc) {
75e5dd7070Spatrick DeclGroupRef DG = dg.get();
76e5dd7070Spatrick
77e5dd7070Spatrick // If we have an invalid decl, just return an error.
78e5dd7070Spatrick if (DG.isNull()) return StmtError();
79e5dd7070Spatrick
80e5dd7070Spatrick return new (Context) DeclStmt(DG, StartLoc, EndLoc);
81e5dd7070Spatrick }
82e5dd7070Spatrick
ActOnForEachDeclStmt(DeclGroupPtrTy dg)83e5dd7070Spatrick void Sema::ActOnForEachDeclStmt(DeclGroupPtrTy dg) {
84e5dd7070Spatrick DeclGroupRef DG = dg.get();
85e5dd7070Spatrick
86e5dd7070Spatrick // If we don't have a declaration, or we have an invalid declaration,
87e5dd7070Spatrick // just return.
88e5dd7070Spatrick if (DG.isNull() || !DG.isSingleDecl())
89e5dd7070Spatrick return;
90e5dd7070Spatrick
91e5dd7070Spatrick Decl *decl = DG.getSingleDecl();
92e5dd7070Spatrick if (!decl || decl->isInvalidDecl())
93e5dd7070Spatrick return;
94e5dd7070Spatrick
95e5dd7070Spatrick // Only variable declarations are permitted.
96e5dd7070Spatrick VarDecl *var = dyn_cast<VarDecl>(decl);
97e5dd7070Spatrick if (!var) {
98e5dd7070Spatrick Diag(decl->getLocation(), diag::err_non_variable_decl_in_for);
99e5dd7070Spatrick decl->setInvalidDecl();
100e5dd7070Spatrick return;
101e5dd7070Spatrick }
102e5dd7070Spatrick
103e5dd7070Spatrick // foreach variables are never actually initialized in the way that
104e5dd7070Spatrick // the parser came up with.
105e5dd7070Spatrick var->setInit(nullptr);
106e5dd7070Spatrick
107e5dd7070Spatrick // In ARC, we don't need to retain the iteration variable of a fast
108e5dd7070Spatrick // enumeration loop. Rather than actually trying to catch that
109e5dd7070Spatrick // during declaration processing, we remove the consequences here.
110e5dd7070Spatrick if (getLangOpts().ObjCAutoRefCount) {
111e5dd7070Spatrick QualType type = var->getType();
112e5dd7070Spatrick
113e5dd7070Spatrick // Only do this if we inferred the lifetime. Inferred lifetime
114e5dd7070Spatrick // will show up as a local qualifier because explicit lifetime
115e5dd7070Spatrick // should have shown up as an AttributedType instead.
116e5dd7070Spatrick if (type.getLocalQualifiers().getObjCLifetime() == Qualifiers::OCL_Strong) {
117e5dd7070Spatrick // Add 'const' and mark the variable as pseudo-strong.
118e5dd7070Spatrick var->setType(type.withConst());
119e5dd7070Spatrick var->setARCPseudoStrong(true);
120e5dd7070Spatrick }
121e5dd7070Spatrick }
122e5dd7070Spatrick }
123e5dd7070Spatrick
124e5dd7070Spatrick /// Diagnose unused comparisons, both builtin and overloaded operators.
125e5dd7070Spatrick /// For '==' and '!=', suggest fixits for '=' or '|='.
126e5dd7070Spatrick ///
127e5dd7070Spatrick /// Adding a cast to void (or other expression wrappers) will prevent the
128e5dd7070Spatrick /// warning from firing.
DiagnoseUnusedComparison(Sema & S,const Expr * E)129e5dd7070Spatrick static bool DiagnoseUnusedComparison(Sema &S, const Expr *E) {
130e5dd7070Spatrick SourceLocation Loc;
131e5dd7070Spatrick bool CanAssign;
132e5dd7070Spatrick enum { Equality, Inequality, Relational, ThreeWay } Kind;
133e5dd7070Spatrick
134e5dd7070Spatrick if (const BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) {
135e5dd7070Spatrick if (!Op->isComparisonOp())
136e5dd7070Spatrick return false;
137e5dd7070Spatrick
138e5dd7070Spatrick if (Op->getOpcode() == BO_EQ)
139e5dd7070Spatrick Kind = Equality;
140e5dd7070Spatrick else if (Op->getOpcode() == BO_NE)
141e5dd7070Spatrick Kind = Inequality;
142e5dd7070Spatrick else if (Op->getOpcode() == BO_Cmp)
143e5dd7070Spatrick Kind = ThreeWay;
144e5dd7070Spatrick else {
145e5dd7070Spatrick assert(Op->isRelationalOp());
146e5dd7070Spatrick Kind = Relational;
147e5dd7070Spatrick }
148e5dd7070Spatrick Loc = Op->getOperatorLoc();
149e5dd7070Spatrick CanAssign = Op->getLHS()->IgnoreParenImpCasts()->isLValue();
150e5dd7070Spatrick } else if (const CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) {
151e5dd7070Spatrick switch (Op->getOperator()) {
152e5dd7070Spatrick case OO_EqualEqual:
153e5dd7070Spatrick Kind = Equality;
154e5dd7070Spatrick break;
155e5dd7070Spatrick case OO_ExclaimEqual:
156e5dd7070Spatrick Kind = Inequality;
157e5dd7070Spatrick break;
158e5dd7070Spatrick case OO_Less:
159e5dd7070Spatrick case OO_Greater:
160e5dd7070Spatrick case OO_GreaterEqual:
161e5dd7070Spatrick case OO_LessEqual:
162e5dd7070Spatrick Kind = Relational;
163e5dd7070Spatrick break;
164e5dd7070Spatrick case OO_Spaceship:
165e5dd7070Spatrick Kind = ThreeWay;
166e5dd7070Spatrick break;
167e5dd7070Spatrick default:
168e5dd7070Spatrick return false;
169e5dd7070Spatrick }
170e5dd7070Spatrick
171e5dd7070Spatrick Loc = Op->getOperatorLoc();
172e5dd7070Spatrick CanAssign = Op->getArg(0)->IgnoreParenImpCasts()->isLValue();
173e5dd7070Spatrick } else {
174e5dd7070Spatrick // Not a typo-prone comparison.
175e5dd7070Spatrick return false;
176e5dd7070Spatrick }
177e5dd7070Spatrick
178e5dd7070Spatrick // Suppress warnings when the operator, suspicious as it may be, comes from
179e5dd7070Spatrick // a macro expansion.
180e5dd7070Spatrick if (S.SourceMgr.isMacroBodyExpansion(Loc))
181e5dd7070Spatrick return false;
182e5dd7070Spatrick
183e5dd7070Spatrick S.Diag(Loc, diag::warn_unused_comparison)
184e5dd7070Spatrick << (unsigned)Kind << E->getSourceRange();
185e5dd7070Spatrick
186e5dd7070Spatrick // If the LHS is a plausible entity to assign to, provide a fixit hint to
187e5dd7070Spatrick // correct common typos.
188e5dd7070Spatrick if (CanAssign) {
189e5dd7070Spatrick if (Kind == Inequality)
190e5dd7070Spatrick S.Diag(Loc, diag::note_inequality_comparison_to_or_assign)
191e5dd7070Spatrick << FixItHint::CreateReplacement(Loc, "|=");
192e5dd7070Spatrick else if (Kind == Equality)
193e5dd7070Spatrick S.Diag(Loc, diag::note_equality_comparison_to_assign)
194e5dd7070Spatrick << FixItHint::CreateReplacement(Loc, "=");
195e5dd7070Spatrick }
196e5dd7070Spatrick
197e5dd7070Spatrick return true;
198e5dd7070Spatrick }
199e5dd7070Spatrick
DiagnoseNoDiscard(Sema & S,const WarnUnusedResultAttr * A,SourceLocation Loc,SourceRange R1,SourceRange R2,bool IsCtor)200e5dd7070Spatrick static bool DiagnoseNoDiscard(Sema &S, const WarnUnusedResultAttr *A,
201e5dd7070Spatrick SourceLocation Loc, SourceRange R1,
202e5dd7070Spatrick SourceRange R2, bool IsCtor) {
203e5dd7070Spatrick if (!A)
204e5dd7070Spatrick return false;
205e5dd7070Spatrick StringRef Msg = A->getMessage();
206e5dd7070Spatrick
207e5dd7070Spatrick if (Msg.empty()) {
208e5dd7070Spatrick if (IsCtor)
209e5dd7070Spatrick return S.Diag(Loc, diag::warn_unused_constructor) << A << R1 << R2;
210e5dd7070Spatrick return S.Diag(Loc, diag::warn_unused_result) << A << R1 << R2;
211e5dd7070Spatrick }
212e5dd7070Spatrick
213e5dd7070Spatrick if (IsCtor)
214e5dd7070Spatrick return S.Diag(Loc, diag::warn_unused_constructor_msg) << A << Msg << R1
215e5dd7070Spatrick << R2;
216e5dd7070Spatrick return S.Diag(Loc, diag::warn_unused_result_msg) << A << Msg << R1 << R2;
217e5dd7070Spatrick }
218e5dd7070Spatrick
DiagnoseUnusedExprResult(const Stmt * S,unsigned DiagID)219*12c85518Srobert void Sema::DiagnoseUnusedExprResult(const Stmt *S, unsigned DiagID) {
220e5dd7070Spatrick if (const LabelStmt *Label = dyn_cast_or_null<LabelStmt>(S))
221*12c85518Srobert return DiagnoseUnusedExprResult(Label->getSubStmt(), DiagID);
222e5dd7070Spatrick
223e5dd7070Spatrick const Expr *E = dyn_cast_or_null<Expr>(S);
224e5dd7070Spatrick if (!E)
225e5dd7070Spatrick return;
226e5dd7070Spatrick
227e5dd7070Spatrick // If we are in an unevaluated expression context, then there can be no unused
228e5dd7070Spatrick // results because the results aren't expected to be used in the first place.
229e5dd7070Spatrick if (isUnevaluatedContext())
230e5dd7070Spatrick return;
231e5dd7070Spatrick
232e5dd7070Spatrick SourceLocation ExprLoc = E->IgnoreParenImpCasts()->getExprLoc();
233e5dd7070Spatrick // In most cases, we don't want to warn if the expression is written in a
234e5dd7070Spatrick // macro body, or if the macro comes from a system header. If the offending
235e5dd7070Spatrick // expression is a call to a function with the warn_unused_result attribute,
236e5dd7070Spatrick // we warn no matter the location. Because of the order in which the various
237e5dd7070Spatrick // checks need to happen, we factor out the macro-related test here.
238e5dd7070Spatrick bool ShouldSuppress =
239e5dd7070Spatrick SourceMgr.isMacroBodyExpansion(ExprLoc) ||
240e5dd7070Spatrick SourceMgr.isInSystemMacro(ExprLoc);
241e5dd7070Spatrick
242e5dd7070Spatrick const Expr *WarnExpr;
243e5dd7070Spatrick SourceLocation Loc;
244e5dd7070Spatrick SourceRange R1, R2;
245e5dd7070Spatrick if (!E->isUnusedResultAWarning(WarnExpr, Loc, R1, R2, Context))
246e5dd7070Spatrick return;
247e5dd7070Spatrick
248e5dd7070Spatrick // If this is a GNU statement expression expanded from a macro, it is probably
249e5dd7070Spatrick // unused because it is a function-like macro that can be used as either an
250e5dd7070Spatrick // expression or statement. Don't warn, because it is almost certainly a
251e5dd7070Spatrick // false positive.
252e5dd7070Spatrick if (isa<StmtExpr>(E) && Loc.isMacroID())
253e5dd7070Spatrick return;
254e5dd7070Spatrick
255e5dd7070Spatrick // Check if this is the UNREFERENCED_PARAMETER from the Microsoft headers.
256e5dd7070Spatrick // That macro is frequently used to suppress "unused parameter" warnings,
257e5dd7070Spatrick // but its implementation makes clang's -Wunused-value fire. Prevent this.
258e5dd7070Spatrick if (isa<ParenExpr>(E->IgnoreImpCasts()) && Loc.isMacroID()) {
259e5dd7070Spatrick SourceLocation SpellLoc = Loc;
260e5dd7070Spatrick if (findMacroSpelling(SpellLoc, "UNREFERENCED_PARAMETER"))
261e5dd7070Spatrick return;
262e5dd7070Spatrick }
263e5dd7070Spatrick
264e5dd7070Spatrick // Okay, we have an unused result. Depending on what the base expression is,
265e5dd7070Spatrick // we might want to make a more specific diagnostic. Check for one of these
266e5dd7070Spatrick // cases now.
267e5dd7070Spatrick if (const FullExpr *Temps = dyn_cast<FullExpr>(E))
268e5dd7070Spatrick E = Temps->getSubExpr();
269e5dd7070Spatrick if (const CXXBindTemporaryExpr *TempExpr = dyn_cast<CXXBindTemporaryExpr>(E))
270e5dd7070Spatrick E = TempExpr->getSubExpr();
271e5dd7070Spatrick
272e5dd7070Spatrick if (DiagnoseUnusedComparison(*this, E))
273e5dd7070Spatrick return;
274e5dd7070Spatrick
275e5dd7070Spatrick E = WarnExpr;
276e5dd7070Spatrick if (const auto *Cast = dyn_cast<CastExpr>(E))
277e5dd7070Spatrick if (Cast->getCastKind() == CK_NoOp ||
278e5dd7070Spatrick Cast->getCastKind() == CK_ConstructorConversion)
279e5dd7070Spatrick E = Cast->getSubExpr()->IgnoreImpCasts();
280e5dd7070Spatrick
281e5dd7070Spatrick if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
282e5dd7070Spatrick if (E->getType()->isVoidType())
283e5dd7070Spatrick return;
284e5dd7070Spatrick
285e5dd7070Spatrick if (DiagnoseNoDiscard(*this, cast_or_null<WarnUnusedResultAttr>(
286e5dd7070Spatrick CE->getUnusedResultAttr(Context)),
287e5dd7070Spatrick Loc, R1, R2, /*isCtor=*/false))
288e5dd7070Spatrick return;
289e5dd7070Spatrick
290e5dd7070Spatrick // If the callee has attribute pure, const, or warn_unused_result, warn with
291e5dd7070Spatrick // a more specific message to make it clear what is happening. If the call
292e5dd7070Spatrick // is written in a macro body, only warn if it has the warn_unused_result
293e5dd7070Spatrick // attribute.
294e5dd7070Spatrick if (const Decl *FD = CE->getCalleeDecl()) {
295e5dd7070Spatrick if (ShouldSuppress)
296e5dd7070Spatrick return;
297e5dd7070Spatrick if (FD->hasAttr<PureAttr>()) {
298e5dd7070Spatrick Diag(Loc, diag::warn_unused_call) << R1 << R2 << "pure";
299e5dd7070Spatrick return;
300e5dd7070Spatrick }
301e5dd7070Spatrick if (FD->hasAttr<ConstAttr>()) {
302e5dd7070Spatrick Diag(Loc, diag::warn_unused_call) << R1 << R2 << "const";
303e5dd7070Spatrick return;
304e5dd7070Spatrick }
305e5dd7070Spatrick }
306e5dd7070Spatrick } else if (const auto *CE = dyn_cast<CXXConstructExpr>(E)) {
307e5dd7070Spatrick if (const CXXConstructorDecl *Ctor = CE->getConstructor()) {
308e5dd7070Spatrick const auto *A = Ctor->getAttr<WarnUnusedResultAttr>();
309e5dd7070Spatrick A = A ? A : Ctor->getParent()->getAttr<WarnUnusedResultAttr>();
310e5dd7070Spatrick if (DiagnoseNoDiscard(*this, A, Loc, R1, R2, /*isCtor=*/true))
311e5dd7070Spatrick return;
312e5dd7070Spatrick }
313e5dd7070Spatrick } else if (const auto *ILE = dyn_cast<InitListExpr>(E)) {
314e5dd7070Spatrick if (const TagDecl *TD = ILE->getType()->getAsTagDecl()) {
315e5dd7070Spatrick
316e5dd7070Spatrick if (DiagnoseNoDiscard(*this, TD->getAttr<WarnUnusedResultAttr>(), Loc, R1,
317e5dd7070Spatrick R2, /*isCtor=*/false))
318e5dd7070Spatrick return;
319e5dd7070Spatrick }
320e5dd7070Spatrick } else if (ShouldSuppress)
321e5dd7070Spatrick return;
322e5dd7070Spatrick
323e5dd7070Spatrick E = WarnExpr;
324e5dd7070Spatrick if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E)) {
325e5dd7070Spatrick if (getLangOpts().ObjCAutoRefCount && ME->isDelegateInitCall()) {
326e5dd7070Spatrick Diag(Loc, diag::err_arc_unused_init_message) << R1;
327e5dd7070Spatrick return;
328e5dd7070Spatrick }
329e5dd7070Spatrick const ObjCMethodDecl *MD = ME->getMethodDecl();
330e5dd7070Spatrick if (MD) {
331e5dd7070Spatrick if (DiagnoseNoDiscard(*this, MD->getAttr<WarnUnusedResultAttr>(), Loc, R1,
332e5dd7070Spatrick R2, /*isCtor=*/false))
333e5dd7070Spatrick return;
334e5dd7070Spatrick }
335e5dd7070Spatrick } else if (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E)) {
336e5dd7070Spatrick const Expr *Source = POE->getSyntacticForm();
337ec727ea7Spatrick // Handle the actually selected call of an OpenMP specialized call.
338ec727ea7Spatrick if (LangOpts.OpenMP && isa<CallExpr>(Source) &&
339ec727ea7Spatrick POE->getNumSemanticExprs() == 1 &&
340ec727ea7Spatrick isa<CallExpr>(POE->getSemanticExpr(0)))
341*12c85518Srobert return DiagnoseUnusedExprResult(POE->getSemanticExpr(0), DiagID);
342e5dd7070Spatrick if (isa<ObjCSubscriptRefExpr>(Source))
343e5dd7070Spatrick DiagID = diag::warn_unused_container_subscript_expr;
344*12c85518Srobert else if (isa<ObjCPropertyRefExpr>(Source))
345e5dd7070Spatrick DiagID = diag::warn_unused_property_expr;
346e5dd7070Spatrick } else if (const CXXFunctionalCastExpr *FC
347e5dd7070Spatrick = dyn_cast<CXXFunctionalCastExpr>(E)) {
348e5dd7070Spatrick const Expr *E = FC->getSubExpr();
349e5dd7070Spatrick if (const CXXBindTemporaryExpr *TE = dyn_cast<CXXBindTemporaryExpr>(E))
350e5dd7070Spatrick E = TE->getSubExpr();
351e5dd7070Spatrick if (isa<CXXTemporaryObjectExpr>(E))
352e5dd7070Spatrick return;
353e5dd7070Spatrick if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(E))
354e5dd7070Spatrick if (const CXXRecordDecl *RD = CE->getType()->getAsCXXRecordDecl())
355e5dd7070Spatrick if (!RD->getAttr<WarnUnusedAttr>())
356e5dd7070Spatrick return;
357e5dd7070Spatrick }
358e5dd7070Spatrick // Diagnose "(void*) blah" as a typo for "(void) blah".
359e5dd7070Spatrick else if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(E)) {
360e5dd7070Spatrick TypeSourceInfo *TI = CE->getTypeInfoAsWritten();
361e5dd7070Spatrick QualType T = TI->getType();
362e5dd7070Spatrick
363e5dd7070Spatrick // We really do want to use the non-canonical type here.
364e5dd7070Spatrick if (T == Context.VoidPtrTy) {
365e5dd7070Spatrick PointerTypeLoc TL = TI->getTypeLoc().castAs<PointerTypeLoc>();
366e5dd7070Spatrick
367e5dd7070Spatrick Diag(Loc, diag::warn_unused_voidptr)
368e5dd7070Spatrick << FixItHint::CreateRemoval(TL.getStarLoc());
369e5dd7070Spatrick return;
370e5dd7070Spatrick }
371e5dd7070Spatrick }
372e5dd7070Spatrick
373ec727ea7Spatrick // Tell the user to assign it into a variable to force a volatile load if this
374ec727ea7Spatrick // isn't an array.
375ec727ea7Spatrick if (E->isGLValue() && E->getType().isVolatileQualified() &&
376ec727ea7Spatrick !E->getType()->isArrayType()) {
377e5dd7070Spatrick Diag(Loc, diag::warn_unused_volatile) << R1 << R2;
378e5dd7070Spatrick return;
379e5dd7070Spatrick }
380e5dd7070Spatrick
381*12c85518Srobert // Do not diagnose use of a comma operator in a SFINAE context because the
382*12c85518Srobert // type of the left operand could be used for SFINAE, so technically it is
383*12c85518Srobert // *used*.
384*12c85518Srobert if (DiagID != diag::warn_unused_comma_left_operand || !isSFINAEContext())
385*12c85518Srobert DiagIfReachable(Loc, S ? llvm::ArrayRef(S) : std::nullopt,
386*12c85518Srobert PDiag(DiagID) << R1 << R2);
387e5dd7070Spatrick }
388e5dd7070Spatrick
ActOnStartOfCompoundStmt(bool IsStmtExpr)389e5dd7070Spatrick void Sema::ActOnStartOfCompoundStmt(bool IsStmtExpr) {
390e5dd7070Spatrick PushCompoundScope(IsStmtExpr);
391e5dd7070Spatrick }
392e5dd7070Spatrick
ActOnAfterCompoundStatementLeadingPragmas()393a9ac8606Spatrick void Sema::ActOnAfterCompoundStatementLeadingPragmas() {
394a9ac8606Spatrick if (getCurFPFeatures().isFPConstrained()) {
395a9ac8606Spatrick FunctionScopeInfo *FSI = getCurFunction();
396a9ac8606Spatrick assert(FSI);
397a9ac8606Spatrick FSI->setUsesFPIntrin();
398a9ac8606Spatrick }
399a9ac8606Spatrick }
400a9ac8606Spatrick
ActOnFinishOfCompoundStmt()401e5dd7070Spatrick void Sema::ActOnFinishOfCompoundStmt() {
402e5dd7070Spatrick PopCompoundScope();
403e5dd7070Spatrick }
404e5dd7070Spatrick
getCurCompoundScope() const405e5dd7070Spatrick sema::CompoundScopeInfo &Sema::getCurCompoundScope() const {
406e5dd7070Spatrick return getCurFunction()->CompoundScopes.back();
407e5dd7070Spatrick }
408e5dd7070Spatrick
ActOnCompoundStmt(SourceLocation L,SourceLocation R,ArrayRef<Stmt * > Elts,bool isStmtExpr)409e5dd7070Spatrick StmtResult Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R,
410e5dd7070Spatrick ArrayRef<Stmt *> Elts, bool isStmtExpr) {
411e5dd7070Spatrick const unsigned NumElts = Elts.size();
412e5dd7070Spatrick
413*12c85518Srobert // If we're in C mode, check that we don't have any decls after stmts. If
414*12c85518Srobert // so, emit an extension diagnostic in C89 and potentially a warning in later
415*12c85518Srobert // versions.
416*12c85518Srobert const unsigned MixedDeclsCodeID = getLangOpts().C99
417*12c85518Srobert ? diag::warn_mixed_decls_code
418*12c85518Srobert : diag::ext_mixed_decls_code;
419*12c85518Srobert if (!getLangOpts().CPlusPlus && !Diags.isIgnored(MixedDeclsCodeID, L)) {
420e5dd7070Spatrick // Note that __extension__ can be around a decl.
421e5dd7070Spatrick unsigned i = 0;
422e5dd7070Spatrick // Skip over all declarations.
423e5dd7070Spatrick for (; i != NumElts && isa<DeclStmt>(Elts[i]); ++i)
424e5dd7070Spatrick /*empty*/;
425e5dd7070Spatrick
426e5dd7070Spatrick // We found the end of the list or a statement. Scan for another declstmt.
427e5dd7070Spatrick for (; i != NumElts && !isa<DeclStmt>(Elts[i]); ++i)
428e5dd7070Spatrick /*empty*/;
429e5dd7070Spatrick
430e5dd7070Spatrick if (i != NumElts) {
431e5dd7070Spatrick Decl *D = *cast<DeclStmt>(Elts[i])->decl_begin();
432*12c85518Srobert Diag(D->getLocation(), MixedDeclsCodeID);
433e5dd7070Spatrick }
434e5dd7070Spatrick }
435e5dd7070Spatrick
436e5dd7070Spatrick // Check for suspicious empty body (null statement) in `for' and `while'
437e5dd7070Spatrick // statements. Don't do anything for template instantiations, this just adds
438e5dd7070Spatrick // noise.
439e5dd7070Spatrick if (NumElts != 0 && !CurrentInstantiationScope &&
440e5dd7070Spatrick getCurCompoundScope().HasEmptyLoopBodies) {
441e5dd7070Spatrick for (unsigned i = 0; i != NumElts - 1; ++i)
442e5dd7070Spatrick DiagnoseEmptyLoopBody(Elts[i], Elts[i + 1]);
443e5dd7070Spatrick }
444e5dd7070Spatrick
445*12c85518Srobert // Calculate difference between FP options in this compound statement and in
446*12c85518Srobert // the enclosing one. If this is a function body, take the difference against
447*12c85518Srobert // default options. In this case the difference will indicate options that are
448*12c85518Srobert // changed upon entry to the statement.
449*12c85518Srobert FPOptions FPO = (getCurFunction()->CompoundScopes.size() == 1)
450*12c85518Srobert ? FPOptions(getLangOpts())
451*12c85518Srobert : getCurCompoundScope().InitialFPFeatures;
452*12c85518Srobert FPOptionsOverride FPDiff = getCurFPFeatures().getChangesFrom(FPO);
453*12c85518Srobert
454*12c85518Srobert return CompoundStmt::Create(Context, Elts, FPDiff, L, R);
455e5dd7070Spatrick }
456e5dd7070Spatrick
457e5dd7070Spatrick ExprResult
ActOnCaseExpr(SourceLocation CaseLoc,ExprResult Val)458e5dd7070Spatrick Sema::ActOnCaseExpr(SourceLocation CaseLoc, ExprResult Val) {
459e5dd7070Spatrick if (!Val.get())
460e5dd7070Spatrick return Val;
461e5dd7070Spatrick
462e5dd7070Spatrick if (DiagnoseUnexpandedParameterPack(Val.get()))
463e5dd7070Spatrick return ExprError();
464e5dd7070Spatrick
465e5dd7070Spatrick // If we're not inside a switch, let the 'case' statement handling diagnose
466e5dd7070Spatrick // this. Just clean up after the expression as best we can.
467e5dd7070Spatrick if (getCurFunction()->SwitchStack.empty())
468e5dd7070Spatrick return ActOnFinishFullExpr(Val.get(), Val.get()->getExprLoc(), false,
469e5dd7070Spatrick getLangOpts().CPlusPlus11);
470e5dd7070Spatrick
471e5dd7070Spatrick Expr *CondExpr =
472e5dd7070Spatrick getCurFunction()->SwitchStack.back().getPointer()->getCond();
473e5dd7070Spatrick if (!CondExpr)
474e5dd7070Spatrick return ExprError();
475e5dd7070Spatrick QualType CondType = CondExpr->getType();
476e5dd7070Spatrick
477e5dd7070Spatrick auto CheckAndFinish = [&](Expr *E) {
478e5dd7070Spatrick if (CondType->isDependentType() || E->isTypeDependent())
479e5dd7070Spatrick return ExprResult(E);
480e5dd7070Spatrick
481e5dd7070Spatrick if (getLangOpts().CPlusPlus11) {
482e5dd7070Spatrick // C++11 [stmt.switch]p2: the constant-expression shall be a converted
483e5dd7070Spatrick // constant expression of the promoted type of the switch condition.
484e5dd7070Spatrick llvm::APSInt TempVal;
485e5dd7070Spatrick return CheckConvertedConstantExpression(E, CondType, TempVal,
486e5dd7070Spatrick CCEK_CaseValue);
487e5dd7070Spatrick }
488e5dd7070Spatrick
489e5dd7070Spatrick ExprResult ER = E;
490e5dd7070Spatrick if (!E->isValueDependent())
491a9ac8606Spatrick ER = VerifyIntegerConstantExpression(E, AllowFold);
492e5dd7070Spatrick if (!ER.isInvalid())
493e5dd7070Spatrick ER = DefaultLvalueConversion(ER.get());
494e5dd7070Spatrick if (!ER.isInvalid())
495e5dd7070Spatrick ER = ImpCastExprToType(ER.get(), CondType, CK_IntegralCast);
496e5dd7070Spatrick if (!ER.isInvalid())
497e5dd7070Spatrick ER = ActOnFinishFullExpr(ER.get(), ER.get()->getExprLoc(), false);
498e5dd7070Spatrick return ER;
499e5dd7070Spatrick };
500e5dd7070Spatrick
501ec727ea7Spatrick ExprResult Converted = CorrectDelayedTyposInExpr(
502ec727ea7Spatrick Val, /*InitDecl=*/nullptr, /*RecoverUncorrectedTypos=*/false,
503ec727ea7Spatrick CheckAndFinish);
504e5dd7070Spatrick if (Converted.get() == Val.get())
505e5dd7070Spatrick Converted = CheckAndFinish(Val.get());
506e5dd7070Spatrick return Converted;
507e5dd7070Spatrick }
508e5dd7070Spatrick
509e5dd7070Spatrick StmtResult
ActOnCaseStmt(SourceLocation CaseLoc,ExprResult LHSVal,SourceLocation DotDotDotLoc,ExprResult RHSVal,SourceLocation ColonLoc)510e5dd7070Spatrick Sema::ActOnCaseStmt(SourceLocation CaseLoc, ExprResult LHSVal,
511e5dd7070Spatrick SourceLocation DotDotDotLoc, ExprResult RHSVal,
512e5dd7070Spatrick SourceLocation ColonLoc) {
513e5dd7070Spatrick assert((LHSVal.isInvalid() || LHSVal.get()) && "missing LHS value");
514e5dd7070Spatrick assert((DotDotDotLoc.isInvalid() ? RHSVal.isUnset()
515e5dd7070Spatrick : RHSVal.isInvalid() || RHSVal.get()) &&
516e5dd7070Spatrick "missing RHS value");
517e5dd7070Spatrick
518e5dd7070Spatrick if (getCurFunction()->SwitchStack.empty()) {
519e5dd7070Spatrick Diag(CaseLoc, diag::err_case_not_in_switch);
520e5dd7070Spatrick return StmtError();
521e5dd7070Spatrick }
522e5dd7070Spatrick
523e5dd7070Spatrick if (LHSVal.isInvalid() || RHSVal.isInvalid()) {
524e5dd7070Spatrick getCurFunction()->SwitchStack.back().setInt(true);
525e5dd7070Spatrick return StmtError();
526e5dd7070Spatrick }
527e5dd7070Spatrick
528e5dd7070Spatrick auto *CS = CaseStmt::Create(Context, LHSVal.get(), RHSVal.get(),
529e5dd7070Spatrick CaseLoc, DotDotDotLoc, ColonLoc);
530e5dd7070Spatrick getCurFunction()->SwitchStack.back().getPointer()->addSwitchCase(CS);
531e5dd7070Spatrick return CS;
532e5dd7070Spatrick }
533e5dd7070Spatrick
534e5dd7070Spatrick /// ActOnCaseStmtBody - This installs a statement as the body of a case.
ActOnCaseStmtBody(Stmt * S,Stmt * SubStmt)535e5dd7070Spatrick void Sema::ActOnCaseStmtBody(Stmt *S, Stmt *SubStmt) {
536e5dd7070Spatrick cast<CaseStmt>(S)->setSubStmt(SubStmt);
537e5dd7070Spatrick }
538e5dd7070Spatrick
539e5dd7070Spatrick StmtResult
ActOnDefaultStmt(SourceLocation DefaultLoc,SourceLocation ColonLoc,Stmt * SubStmt,Scope * CurScope)540e5dd7070Spatrick Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc,
541e5dd7070Spatrick Stmt *SubStmt, Scope *CurScope) {
542e5dd7070Spatrick if (getCurFunction()->SwitchStack.empty()) {
543e5dd7070Spatrick Diag(DefaultLoc, diag::err_default_not_in_switch);
544e5dd7070Spatrick return SubStmt;
545e5dd7070Spatrick }
546e5dd7070Spatrick
547e5dd7070Spatrick DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt);
548e5dd7070Spatrick getCurFunction()->SwitchStack.back().getPointer()->addSwitchCase(DS);
549e5dd7070Spatrick return DS;
550e5dd7070Spatrick }
551e5dd7070Spatrick
552e5dd7070Spatrick StmtResult
ActOnLabelStmt(SourceLocation IdentLoc,LabelDecl * TheDecl,SourceLocation ColonLoc,Stmt * SubStmt)553e5dd7070Spatrick Sema::ActOnLabelStmt(SourceLocation IdentLoc, LabelDecl *TheDecl,
554e5dd7070Spatrick SourceLocation ColonLoc, Stmt *SubStmt) {
555e5dd7070Spatrick // If the label was multiply defined, reject it now.
556e5dd7070Spatrick if (TheDecl->getStmt()) {
557e5dd7070Spatrick Diag(IdentLoc, diag::err_redefinition_of_label) << TheDecl->getDeclName();
558e5dd7070Spatrick Diag(TheDecl->getLocation(), diag::note_previous_definition);
559e5dd7070Spatrick return SubStmt;
560e5dd7070Spatrick }
561e5dd7070Spatrick
562a9ac8606Spatrick ReservedIdentifierStatus Status = TheDecl->isReserved(getLangOpts());
563*12c85518Srobert if (isReservedInAllContexts(Status) &&
564a9ac8606Spatrick !Context.getSourceManager().isInSystemHeader(IdentLoc))
565a9ac8606Spatrick Diag(IdentLoc, diag::warn_reserved_extern_symbol)
566a9ac8606Spatrick << TheDecl << static_cast<int>(Status);
567a9ac8606Spatrick
568e5dd7070Spatrick // Otherwise, things are good. Fill in the declaration and return it.
569e5dd7070Spatrick LabelStmt *LS = new (Context) LabelStmt(IdentLoc, TheDecl, SubStmt);
570e5dd7070Spatrick TheDecl->setStmt(LS);
571e5dd7070Spatrick if (!TheDecl->isGnuLocal()) {
572e5dd7070Spatrick TheDecl->setLocStart(IdentLoc);
573e5dd7070Spatrick if (!TheDecl->isMSAsmLabel()) {
574e5dd7070Spatrick // Don't update the location of MS ASM labels. These will result in
575e5dd7070Spatrick // a diagnostic, and changing the location here will mess that up.
576e5dd7070Spatrick TheDecl->setLocation(IdentLoc);
577e5dd7070Spatrick }
578e5dd7070Spatrick }
579e5dd7070Spatrick return LS;
580e5dd7070Spatrick }
581e5dd7070Spatrick
BuildAttributedStmt(SourceLocation AttrsLoc,ArrayRef<const Attr * > Attrs,Stmt * SubStmt)582a9ac8606Spatrick StmtResult Sema::BuildAttributedStmt(SourceLocation AttrsLoc,
583e5dd7070Spatrick ArrayRef<const Attr *> Attrs,
584e5dd7070Spatrick Stmt *SubStmt) {
585a9ac8606Spatrick // FIXME: this code should move when a planned refactoring around statement
586a9ac8606Spatrick // attributes lands.
587a9ac8606Spatrick for (const auto *A : Attrs) {
588a9ac8606Spatrick if (A->getKind() == attr::MustTail) {
589a9ac8606Spatrick if (!checkAndRewriteMustTailAttr(SubStmt, *A)) {
590a9ac8606Spatrick return SubStmt;
591a9ac8606Spatrick }
592a9ac8606Spatrick setFunctionHasMustTail();
593a9ac8606Spatrick }
594a9ac8606Spatrick }
595a9ac8606Spatrick
596a9ac8606Spatrick return AttributedStmt::Create(Context, AttrsLoc, Attrs, SubStmt);
597a9ac8606Spatrick }
598a9ac8606Spatrick
ActOnAttributedStmt(const ParsedAttributes & Attrs,Stmt * SubStmt)599*12c85518Srobert StmtResult Sema::ActOnAttributedStmt(const ParsedAttributes &Attrs,
600a9ac8606Spatrick Stmt *SubStmt) {
601a9ac8606Spatrick SmallVector<const Attr *, 1> SemanticAttrs;
602a9ac8606Spatrick ProcessStmtAttributes(SubStmt, Attrs, SemanticAttrs);
603a9ac8606Spatrick if (!SemanticAttrs.empty())
604a9ac8606Spatrick return BuildAttributedStmt(Attrs.Range.getBegin(), SemanticAttrs, SubStmt);
605a9ac8606Spatrick // If none of the attributes applied, that's fine, we can recover by
606a9ac8606Spatrick // returning the substatement directly instead of making an AttributedStmt
607a9ac8606Spatrick // with no attributes on it.
608a9ac8606Spatrick return SubStmt;
609a9ac8606Spatrick }
610a9ac8606Spatrick
checkAndRewriteMustTailAttr(Stmt * St,const Attr & MTA)611a9ac8606Spatrick bool Sema::checkAndRewriteMustTailAttr(Stmt *St, const Attr &MTA) {
612a9ac8606Spatrick ReturnStmt *R = cast<ReturnStmt>(St);
613a9ac8606Spatrick Expr *E = R->getRetValue();
614a9ac8606Spatrick
615a9ac8606Spatrick if (CurContext->isDependentContext() || (E && E->isInstantiationDependent()))
616a9ac8606Spatrick // We have to suspend our check until template instantiation time.
617a9ac8606Spatrick return true;
618a9ac8606Spatrick
619a9ac8606Spatrick if (!checkMustTailAttr(St, MTA))
620a9ac8606Spatrick return false;
621a9ac8606Spatrick
622a9ac8606Spatrick // FIXME: Replace Expr::IgnoreImplicitAsWritten() with this function.
623a9ac8606Spatrick // Currently it does not skip implicit constructors in an initialization
624a9ac8606Spatrick // context.
625a9ac8606Spatrick auto IgnoreImplicitAsWritten = [](Expr *E) -> Expr * {
626a9ac8606Spatrick return IgnoreExprNodes(E, IgnoreImplicitAsWrittenSingleStep,
627a9ac8606Spatrick IgnoreElidableImplicitConstructorSingleStep);
628a9ac8606Spatrick };
629a9ac8606Spatrick
630a9ac8606Spatrick // Now that we have verified that 'musttail' is valid here, rewrite the
631a9ac8606Spatrick // return value to remove all implicit nodes, but retain parentheses.
632a9ac8606Spatrick R->setRetValue(IgnoreImplicitAsWritten(E));
633a9ac8606Spatrick return true;
634a9ac8606Spatrick }
635a9ac8606Spatrick
checkMustTailAttr(const Stmt * St,const Attr & MTA)636a9ac8606Spatrick bool Sema::checkMustTailAttr(const Stmt *St, const Attr &MTA) {
637a9ac8606Spatrick assert(!CurContext->isDependentContext() &&
638a9ac8606Spatrick "musttail cannot be checked from a dependent context");
639a9ac8606Spatrick
640a9ac8606Spatrick // FIXME: Add Expr::IgnoreParenImplicitAsWritten() with this definition.
641a9ac8606Spatrick auto IgnoreParenImplicitAsWritten = [](const Expr *E) -> const Expr * {
642a9ac8606Spatrick return IgnoreExprNodes(const_cast<Expr *>(E), IgnoreParensSingleStep,
643a9ac8606Spatrick IgnoreImplicitAsWrittenSingleStep,
644a9ac8606Spatrick IgnoreElidableImplicitConstructorSingleStep);
645a9ac8606Spatrick };
646a9ac8606Spatrick
647a9ac8606Spatrick const Expr *E = cast<ReturnStmt>(St)->getRetValue();
648a9ac8606Spatrick const auto *CE = dyn_cast_or_null<CallExpr>(IgnoreParenImplicitAsWritten(E));
649a9ac8606Spatrick
650a9ac8606Spatrick if (!CE) {
651a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_needs_call) << &MTA;
652a9ac8606Spatrick return false;
653a9ac8606Spatrick }
654a9ac8606Spatrick
655a9ac8606Spatrick if (const auto *EWC = dyn_cast<ExprWithCleanups>(E)) {
656a9ac8606Spatrick if (EWC->cleanupsHaveSideEffects()) {
657a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_needs_trivial_args) << &MTA;
658a9ac8606Spatrick return false;
659a9ac8606Spatrick }
660a9ac8606Spatrick }
661a9ac8606Spatrick
662a9ac8606Spatrick // We need to determine the full function type (including "this" type, if any)
663a9ac8606Spatrick // for both caller and callee.
664a9ac8606Spatrick struct FuncType {
665a9ac8606Spatrick enum {
666a9ac8606Spatrick ft_non_member,
667a9ac8606Spatrick ft_static_member,
668a9ac8606Spatrick ft_non_static_member,
669a9ac8606Spatrick ft_pointer_to_member,
670a9ac8606Spatrick } MemberType = ft_non_member;
671a9ac8606Spatrick
672a9ac8606Spatrick QualType This;
673a9ac8606Spatrick const FunctionProtoType *Func;
674a9ac8606Spatrick const CXXMethodDecl *Method = nullptr;
675a9ac8606Spatrick } CallerType, CalleeType;
676a9ac8606Spatrick
677a9ac8606Spatrick auto GetMethodType = [this, St, MTA](const CXXMethodDecl *CMD, FuncType &Type,
678a9ac8606Spatrick bool IsCallee) -> bool {
679a9ac8606Spatrick if (isa<CXXConstructorDecl, CXXDestructorDecl>(CMD)) {
680a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_structors_forbidden)
681a9ac8606Spatrick << IsCallee << isa<CXXDestructorDecl>(CMD);
682a9ac8606Spatrick if (IsCallee)
683a9ac8606Spatrick Diag(CMD->getBeginLoc(), diag::note_musttail_structors_forbidden)
684a9ac8606Spatrick << isa<CXXDestructorDecl>(CMD);
685a9ac8606Spatrick Diag(MTA.getLocation(), diag::note_tail_call_required) << &MTA;
686a9ac8606Spatrick return false;
687a9ac8606Spatrick }
688a9ac8606Spatrick if (CMD->isStatic())
689a9ac8606Spatrick Type.MemberType = FuncType::ft_static_member;
690a9ac8606Spatrick else {
691a9ac8606Spatrick Type.This = CMD->getThisType()->getPointeeType();
692a9ac8606Spatrick Type.MemberType = FuncType::ft_non_static_member;
693a9ac8606Spatrick }
694a9ac8606Spatrick Type.Func = CMD->getType()->castAs<FunctionProtoType>();
695a9ac8606Spatrick return true;
696a9ac8606Spatrick };
697a9ac8606Spatrick
698a9ac8606Spatrick const auto *CallerDecl = dyn_cast<FunctionDecl>(CurContext);
699a9ac8606Spatrick
700a9ac8606Spatrick // Find caller function signature.
701a9ac8606Spatrick if (!CallerDecl) {
702a9ac8606Spatrick int ContextType;
703a9ac8606Spatrick if (isa<BlockDecl>(CurContext))
704a9ac8606Spatrick ContextType = 0;
705a9ac8606Spatrick else if (isa<ObjCMethodDecl>(CurContext))
706a9ac8606Spatrick ContextType = 1;
707a9ac8606Spatrick else
708a9ac8606Spatrick ContextType = 2;
709a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_forbidden_from_this_context)
710a9ac8606Spatrick << &MTA << ContextType;
711a9ac8606Spatrick return false;
712a9ac8606Spatrick } else if (const auto *CMD = dyn_cast<CXXMethodDecl>(CurContext)) {
713a9ac8606Spatrick // Caller is a class/struct method.
714a9ac8606Spatrick if (!GetMethodType(CMD, CallerType, false))
715a9ac8606Spatrick return false;
716a9ac8606Spatrick } else {
717a9ac8606Spatrick // Caller is a non-method function.
718a9ac8606Spatrick CallerType.Func = CallerDecl->getType()->getAs<FunctionProtoType>();
719a9ac8606Spatrick }
720a9ac8606Spatrick
721a9ac8606Spatrick const Expr *CalleeExpr = CE->getCallee()->IgnoreParens();
722a9ac8606Spatrick const auto *CalleeBinOp = dyn_cast<BinaryOperator>(CalleeExpr);
723a9ac8606Spatrick SourceLocation CalleeLoc = CE->getCalleeDecl()
724a9ac8606Spatrick ? CE->getCalleeDecl()->getBeginLoc()
725a9ac8606Spatrick : St->getBeginLoc();
726a9ac8606Spatrick
727a9ac8606Spatrick // Find callee function signature.
728a9ac8606Spatrick if (const CXXMethodDecl *CMD =
729a9ac8606Spatrick dyn_cast_or_null<CXXMethodDecl>(CE->getCalleeDecl())) {
730a9ac8606Spatrick // Call is: obj.method(), obj->method(), functor(), etc.
731a9ac8606Spatrick if (!GetMethodType(CMD, CalleeType, true))
732a9ac8606Spatrick return false;
733a9ac8606Spatrick } else if (CalleeBinOp && CalleeBinOp->isPtrMemOp()) {
734a9ac8606Spatrick // Call is: obj->*method_ptr or obj.*method_ptr
735a9ac8606Spatrick const auto *MPT =
736a9ac8606Spatrick CalleeBinOp->getRHS()->getType()->castAs<MemberPointerType>();
737a9ac8606Spatrick CalleeType.This = QualType(MPT->getClass(), 0);
738a9ac8606Spatrick CalleeType.Func = MPT->getPointeeType()->castAs<FunctionProtoType>();
739a9ac8606Spatrick CalleeType.MemberType = FuncType::ft_pointer_to_member;
740a9ac8606Spatrick } else if (isa<CXXPseudoDestructorExpr>(CalleeExpr)) {
741a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_structors_forbidden)
742a9ac8606Spatrick << /* IsCallee = */ 1 << /* IsDestructor = */ 1;
743a9ac8606Spatrick Diag(MTA.getLocation(), diag::note_tail_call_required) << &MTA;
744a9ac8606Spatrick return false;
745a9ac8606Spatrick } else {
746a9ac8606Spatrick // Non-method function.
747a9ac8606Spatrick CalleeType.Func =
748a9ac8606Spatrick CalleeExpr->getType()->getPointeeType()->getAs<FunctionProtoType>();
749a9ac8606Spatrick }
750a9ac8606Spatrick
751a9ac8606Spatrick // Both caller and callee must have a prototype (no K&R declarations).
752a9ac8606Spatrick if (!CalleeType.Func || !CallerType.Func) {
753a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_needs_prototype) << &MTA;
754a9ac8606Spatrick if (!CalleeType.Func && CE->getDirectCallee()) {
755a9ac8606Spatrick Diag(CE->getDirectCallee()->getBeginLoc(),
756a9ac8606Spatrick diag::note_musttail_fix_non_prototype);
757a9ac8606Spatrick }
758a9ac8606Spatrick if (!CallerType.Func)
759a9ac8606Spatrick Diag(CallerDecl->getBeginLoc(), diag::note_musttail_fix_non_prototype);
760a9ac8606Spatrick return false;
761a9ac8606Spatrick }
762a9ac8606Spatrick
763a9ac8606Spatrick // Caller and callee must have matching calling conventions.
764a9ac8606Spatrick //
765a9ac8606Spatrick // Some calling conventions are physically capable of supporting tail calls
766a9ac8606Spatrick // even if the function types don't perfectly match. LLVM is currently too
767a9ac8606Spatrick // strict to allow this, but if LLVM added support for this in the future, we
768a9ac8606Spatrick // could exit early here and skip the remaining checks if the functions are
769a9ac8606Spatrick // using such a calling convention.
770a9ac8606Spatrick if (CallerType.Func->getCallConv() != CalleeType.Func->getCallConv()) {
771a9ac8606Spatrick if (const auto *ND = dyn_cast_or_null<NamedDecl>(CE->getCalleeDecl()))
772a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_callconv_mismatch)
773a9ac8606Spatrick << true << ND->getDeclName();
774a9ac8606Spatrick else
775a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_callconv_mismatch) << false;
776a9ac8606Spatrick Diag(CalleeLoc, diag::note_musttail_callconv_mismatch)
777a9ac8606Spatrick << FunctionType::getNameForCallConv(CallerType.Func->getCallConv())
778a9ac8606Spatrick << FunctionType::getNameForCallConv(CalleeType.Func->getCallConv());
779a9ac8606Spatrick Diag(MTA.getLocation(), diag::note_tail_call_required) << &MTA;
780a9ac8606Spatrick return false;
781a9ac8606Spatrick }
782a9ac8606Spatrick
783a9ac8606Spatrick if (CalleeType.Func->isVariadic() || CallerType.Func->isVariadic()) {
784a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_no_variadic) << &MTA;
785a9ac8606Spatrick return false;
786a9ac8606Spatrick }
787a9ac8606Spatrick
788a9ac8606Spatrick // Caller and callee must match in whether they have a "this" parameter.
789a9ac8606Spatrick if (CallerType.This.isNull() != CalleeType.This.isNull()) {
790a9ac8606Spatrick if (const auto *ND = dyn_cast_or_null<NamedDecl>(CE->getCalleeDecl())) {
791a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_member_mismatch)
792a9ac8606Spatrick << CallerType.MemberType << CalleeType.MemberType << true
793a9ac8606Spatrick << ND->getDeclName();
794a9ac8606Spatrick Diag(CalleeLoc, diag::note_musttail_callee_defined_here)
795a9ac8606Spatrick << ND->getDeclName();
796a9ac8606Spatrick } else
797a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_member_mismatch)
798a9ac8606Spatrick << CallerType.MemberType << CalleeType.MemberType << false;
799a9ac8606Spatrick Diag(MTA.getLocation(), diag::note_tail_call_required) << &MTA;
800a9ac8606Spatrick return false;
801a9ac8606Spatrick }
802a9ac8606Spatrick
803a9ac8606Spatrick auto CheckTypesMatch = [this](FuncType CallerType, FuncType CalleeType,
804a9ac8606Spatrick PartialDiagnostic &PD) -> bool {
805a9ac8606Spatrick enum {
806a9ac8606Spatrick ft_different_class,
807a9ac8606Spatrick ft_parameter_arity,
808a9ac8606Spatrick ft_parameter_mismatch,
809a9ac8606Spatrick ft_return_type,
810a9ac8606Spatrick };
811a9ac8606Spatrick
812a9ac8606Spatrick auto DoTypesMatch = [this, &PD](QualType A, QualType B,
813a9ac8606Spatrick unsigned Select) -> bool {
814a9ac8606Spatrick if (!Context.hasSimilarType(A, B)) {
815a9ac8606Spatrick PD << Select << A.getUnqualifiedType() << B.getUnqualifiedType();
816a9ac8606Spatrick return false;
817a9ac8606Spatrick }
818a9ac8606Spatrick return true;
819a9ac8606Spatrick };
820a9ac8606Spatrick
821a9ac8606Spatrick if (!CallerType.This.isNull() &&
822a9ac8606Spatrick !DoTypesMatch(CallerType.This, CalleeType.This, ft_different_class))
823a9ac8606Spatrick return false;
824a9ac8606Spatrick
825a9ac8606Spatrick if (!DoTypesMatch(CallerType.Func->getReturnType(),
826a9ac8606Spatrick CalleeType.Func->getReturnType(), ft_return_type))
827a9ac8606Spatrick return false;
828a9ac8606Spatrick
829a9ac8606Spatrick if (CallerType.Func->getNumParams() != CalleeType.Func->getNumParams()) {
830a9ac8606Spatrick PD << ft_parameter_arity << CallerType.Func->getNumParams()
831a9ac8606Spatrick << CalleeType.Func->getNumParams();
832a9ac8606Spatrick return false;
833a9ac8606Spatrick }
834a9ac8606Spatrick
835a9ac8606Spatrick ArrayRef<QualType> CalleeParams = CalleeType.Func->getParamTypes();
836a9ac8606Spatrick ArrayRef<QualType> CallerParams = CallerType.Func->getParamTypes();
837a9ac8606Spatrick size_t N = CallerType.Func->getNumParams();
838a9ac8606Spatrick for (size_t I = 0; I < N; I++) {
839a9ac8606Spatrick if (!DoTypesMatch(CalleeParams[I], CallerParams[I],
840a9ac8606Spatrick ft_parameter_mismatch)) {
841a9ac8606Spatrick PD << static_cast<int>(I) + 1;
842a9ac8606Spatrick return false;
843a9ac8606Spatrick }
844a9ac8606Spatrick }
845a9ac8606Spatrick
846a9ac8606Spatrick return true;
847a9ac8606Spatrick };
848a9ac8606Spatrick
849a9ac8606Spatrick PartialDiagnostic PD = PDiag(diag::note_musttail_mismatch);
850a9ac8606Spatrick if (!CheckTypesMatch(CallerType, CalleeType, PD)) {
851a9ac8606Spatrick if (const auto *ND = dyn_cast_or_null<NamedDecl>(CE->getCalleeDecl()))
852a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_mismatch)
853a9ac8606Spatrick << true << ND->getDeclName();
854a9ac8606Spatrick else
855a9ac8606Spatrick Diag(St->getBeginLoc(), diag::err_musttail_mismatch) << false;
856a9ac8606Spatrick Diag(CalleeLoc, PD);
857a9ac8606Spatrick Diag(MTA.getLocation(), diag::note_tail_call_required) << &MTA;
858a9ac8606Spatrick return false;
859a9ac8606Spatrick }
860a9ac8606Spatrick
861a9ac8606Spatrick return true;
862e5dd7070Spatrick }
863e5dd7070Spatrick
864e5dd7070Spatrick namespace {
865e5dd7070Spatrick class CommaVisitor : public EvaluatedExprVisitor<CommaVisitor> {
866e5dd7070Spatrick typedef EvaluatedExprVisitor<CommaVisitor> Inherited;
867e5dd7070Spatrick Sema &SemaRef;
868e5dd7070Spatrick public:
CommaVisitor(Sema & SemaRef)869e5dd7070Spatrick CommaVisitor(Sema &SemaRef) : Inherited(SemaRef.Context), SemaRef(SemaRef) {}
VisitBinaryOperator(BinaryOperator * E)870e5dd7070Spatrick void VisitBinaryOperator(BinaryOperator *E) {
871e5dd7070Spatrick if (E->getOpcode() == BO_Comma)
872e5dd7070Spatrick SemaRef.DiagnoseCommaOperator(E->getLHS(), E->getExprLoc());
873e5dd7070Spatrick EvaluatedExprVisitor<CommaVisitor>::VisitBinaryOperator(E);
874e5dd7070Spatrick }
875e5dd7070Spatrick };
876e5dd7070Spatrick }
877e5dd7070Spatrick
ActOnIfStmt(SourceLocation IfLoc,IfStatementKind StatementKind,SourceLocation LParenLoc,Stmt * InitStmt,ConditionResult Cond,SourceLocation RParenLoc,Stmt * thenStmt,SourceLocation ElseLoc,Stmt * elseStmt)878*12c85518Srobert StmtResult Sema::ActOnIfStmt(SourceLocation IfLoc,
879*12c85518Srobert IfStatementKind StatementKind,
880a9ac8606Spatrick SourceLocation LParenLoc, Stmt *InitStmt,
881a9ac8606Spatrick ConditionResult Cond, SourceLocation RParenLoc,
882e5dd7070Spatrick Stmt *thenStmt, SourceLocation ElseLoc,
883e5dd7070Spatrick Stmt *elseStmt) {
884e5dd7070Spatrick if (Cond.isInvalid())
885*12c85518Srobert return StmtError();
886*12c85518Srobert
887*12c85518Srobert bool ConstevalOrNegatedConsteval =
888*12c85518Srobert StatementKind == IfStatementKind::ConstevalNonNegated ||
889*12c85518Srobert StatementKind == IfStatementKind::ConstevalNegated;
890e5dd7070Spatrick
891e5dd7070Spatrick Expr *CondExpr = Cond.get().second;
892*12c85518Srobert assert((CondExpr || ConstevalOrNegatedConsteval) &&
893*12c85518Srobert "If statement: missing condition");
894e5dd7070Spatrick // Only call the CommaVisitor when not C89 due to differences in scope flags.
895*12c85518Srobert if (CondExpr && (getLangOpts().C99 || getLangOpts().CPlusPlus) &&
896e5dd7070Spatrick !Diags.isIgnored(diag::warn_comma_operator, CondExpr->getExprLoc()))
897e5dd7070Spatrick CommaVisitor(*this).Visit(CondExpr);
898e5dd7070Spatrick
899*12c85518Srobert if (!ConstevalOrNegatedConsteval && !elseStmt)
900*12c85518Srobert DiagnoseEmptyStmtBody(RParenLoc, thenStmt, diag::warn_empty_if_body);
901e5dd7070Spatrick
902*12c85518Srobert if (ConstevalOrNegatedConsteval ||
903*12c85518Srobert StatementKind == IfStatementKind::Constexpr) {
904a9ac8606Spatrick auto DiagnoseLikelihood = [&](const Stmt *S) {
905a9ac8606Spatrick if (const Attr *A = Stmt::getLikelihoodAttr(S)) {
906a9ac8606Spatrick Diags.Report(A->getLocation(),
907*12c85518Srobert diag::warn_attribute_has_no_effect_on_compile_time_if)
908*12c85518Srobert << A << ConstevalOrNegatedConsteval << A->getRange();
909a9ac8606Spatrick Diags.Report(IfLoc,
910*12c85518Srobert diag::note_attribute_has_no_effect_on_compile_time_if_here)
911*12c85518Srobert << ConstevalOrNegatedConsteval
912*12c85518Srobert << SourceRange(IfLoc, (ConstevalOrNegatedConsteval
913*12c85518Srobert ? thenStmt->getBeginLoc()
914*12c85518Srobert : LParenLoc)
915*12c85518Srobert .getLocWithOffset(-1));
916a9ac8606Spatrick }
917a9ac8606Spatrick };
918a9ac8606Spatrick DiagnoseLikelihood(thenStmt);
919a9ac8606Spatrick DiagnoseLikelihood(elseStmt);
920a9ac8606Spatrick } else {
921a9ac8606Spatrick std::tuple<bool, const Attr *, const Attr *> LHC =
922a9ac8606Spatrick Stmt::determineLikelihoodConflict(thenStmt, elseStmt);
923a9ac8606Spatrick if (std::get<0>(LHC)) {
924a9ac8606Spatrick const Attr *ThenAttr = std::get<1>(LHC);
925a9ac8606Spatrick const Attr *ElseAttr = std::get<2>(LHC);
926a9ac8606Spatrick Diags.Report(ThenAttr->getLocation(),
927a9ac8606Spatrick diag::warn_attributes_likelihood_ifstmt_conflict)
928a9ac8606Spatrick << ThenAttr << ThenAttr->getRange();
929a9ac8606Spatrick Diags.Report(ElseAttr->getLocation(), diag::note_conflicting_attribute)
930a9ac8606Spatrick << ElseAttr << ElseAttr->getRange();
931a9ac8606Spatrick }
932a9ac8606Spatrick }
933a9ac8606Spatrick
934*12c85518Srobert if (ConstevalOrNegatedConsteval) {
935*12c85518Srobert bool Immediate = isImmediateFunctionContext();
936*12c85518Srobert if (CurContext->isFunctionOrMethod()) {
937*12c85518Srobert const auto *FD =
938*12c85518Srobert dyn_cast<FunctionDecl>(Decl::castFromDeclContext(CurContext));
939*12c85518Srobert if (FD && FD->isConsteval())
940*12c85518Srobert Immediate = true;
941*12c85518Srobert }
942*12c85518Srobert if (isUnevaluatedContext() || Immediate)
943*12c85518Srobert Diags.Report(IfLoc, diag::warn_consteval_if_always_true) << Immediate;
944*12c85518Srobert }
945*12c85518Srobert
946*12c85518Srobert return BuildIfStmt(IfLoc, StatementKind, LParenLoc, InitStmt, Cond, RParenLoc,
947a9ac8606Spatrick thenStmt, ElseLoc, elseStmt);
948e5dd7070Spatrick }
949e5dd7070Spatrick
BuildIfStmt(SourceLocation IfLoc,IfStatementKind StatementKind,SourceLocation LParenLoc,Stmt * InitStmt,ConditionResult Cond,SourceLocation RParenLoc,Stmt * thenStmt,SourceLocation ElseLoc,Stmt * elseStmt)950*12c85518Srobert StmtResult Sema::BuildIfStmt(SourceLocation IfLoc,
951*12c85518Srobert IfStatementKind StatementKind,
952a9ac8606Spatrick SourceLocation LParenLoc, Stmt *InitStmt,
953a9ac8606Spatrick ConditionResult Cond, SourceLocation RParenLoc,
954e5dd7070Spatrick Stmt *thenStmt, SourceLocation ElseLoc,
955e5dd7070Spatrick Stmt *elseStmt) {
956e5dd7070Spatrick if (Cond.isInvalid())
957e5dd7070Spatrick return StmtError();
958e5dd7070Spatrick
959*12c85518Srobert if (StatementKind != IfStatementKind::Ordinary ||
960*12c85518Srobert isa<ObjCAvailabilityCheckExpr>(Cond.get().second))
961e5dd7070Spatrick setFunctionHasBranchProtectedScope();
962e5dd7070Spatrick
963*12c85518Srobert return IfStmt::Create(Context, IfLoc, StatementKind, InitStmt,
964*12c85518Srobert Cond.get().first, Cond.get().second, LParenLoc,
965*12c85518Srobert RParenLoc, thenStmt, ElseLoc, elseStmt);
966e5dd7070Spatrick }
967e5dd7070Spatrick
968e5dd7070Spatrick namespace {
969e5dd7070Spatrick struct CaseCompareFunctor {
operator ()__anonceb37bf40c11::CaseCompareFunctor970e5dd7070Spatrick bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
971e5dd7070Spatrick const llvm::APSInt &RHS) {
972e5dd7070Spatrick return LHS.first < RHS;
973e5dd7070Spatrick }
operator ()__anonceb37bf40c11::CaseCompareFunctor974e5dd7070Spatrick bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
975e5dd7070Spatrick const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
976e5dd7070Spatrick return LHS.first < RHS.first;
977e5dd7070Spatrick }
operator ()__anonceb37bf40c11::CaseCompareFunctor978e5dd7070Spatrick bool operator()(const llvm::APSInt &LHS,
979e5dd7070Spatrick const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
980e5dd7070Spatrick return LHS < RHS.first;
981e5dd7070Spatrick }
982e5dd7070Spatrick };
983e5dd7070Spatrick }
984e5dd7070Spatrick
985e5dd7070Spatrick /// CmpCaseVals - Comparison predicate for sorting case values.
986e5dd7070Spatrick ///
CmpCaseVals(const std::pair<llvm::APSInt,CaseStmt * > & lhs,const std::pair<llvm::APSInt,CaseStmt * > & rhs)987e5dd7070Spatrick static bool CmpCaseVals(const std::pair<llvm::APSInt, CaseStmt*>& lhs,
988e5dd7070Spatrick const std::pair<llvm::APSInt, CaseStmt*>& rhs) {
989e5dd7070Spatrick if (lhs.first < rhs.first)
990e5dd7070Spatrick return true;
991e5dd7070Spatrick
992e5dd7070Spatrick if (lhs.first == rhs.first &&
993a9ac8606Spatrick lhs.second->getCaseLoc() < rhs.second->getCaseLoc())
994e5dd7070Spatrick return true;
995e5dd7070Spatrick return false;
996e5dd7070Spatrick }
997e5dd7070Spatrick
998e5dd7070Spatrick /// CmpEnumVals - Comparison predicate for sorting enumeration values.
999e5dd7070Spatrick ///
CmpEnumVals(const std::pair<llvm::APSInt,EnumConstantDecl * > & lhs,const std::pair<llvm::APSInt,EnumConstantDecl * > & rhs)1000e5dd7070Spatrick static bool CmpEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs,
1001e5dd7070Spatrick const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs)
1002e5dd7070Spatrick {
1003e5dd7070Spatrick return lhs.first < rhs.first;
1004e5dd7070Spatrick }
1005e5dd7070Spatrick
1006e5dd7070Spatrick /// EqEnumVals - Comparison preficate for uniqing enumeration values.
1007e5dd7070Spatrick ///
EqEnumVals(const std::pair<llvm::APSInt,EnumConstantDecl * > & lhs,const std::pair<llvm::APSInt,EnumConstantDecl * > & rhs)1008e5dd7070Spatrick static bool EqEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs,
1009e5dd7070Spatrick const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs)
1010e5dd7070Spatrick {
1011e5dd7070Spatrick return lhs.first == rhs.first;
1012e5dd7070Spatrick }
1013e5dd7070Spatrick
1014e5dd7070Spatrick /// GetTypeBeforeIntegralPromotion - Returns the pre-promotion type of
1015e5dd7070Spatrick /// potentially integral-promoted expression @p expr.
GetTypeBeforeIntegralPromotion(const Expr * & E)1016e5dd7070Spatrick static QualType GetTypeBeforeIntegralPromotion(const Expr *&E) {
1017e5dd7070Spatrick if (const auto *FE = dyn_cast<FullExpr>(E))
1018e5dd7070Spatrick E = FE->getSubExpr();
1019e5dd7070Spatrick while (const auto *ImpCast = dyn_cast<ImplicitCastExpr>(E)) {
1020e5dd7070Spatrick if (ImpCast->getCastKind() != CK_IntegralCast) break;
1021e5dd7070Spatrick E = ImpCast->getSubExpr();
1022e5dd7070Spatrick }
1023e5dd7070Spatrick return E->getType();
1024e5dd7070Spatrick }
1025e5dd7070Spatrick
CheckSwitchCondition(SourceLocation SwitchLoc,Expr * Cond)1026e5dd7070Spatrick ExprResult Sema::CheckSwitchCondition(SourceLocation SwitchLoc, Expr *Cond) {
1027e5dd7070Spatrick class SwitchConvertDiagnoser : public ICEConvertDiagnoser {
1028e5dd7070Spatrick Expr *Cond;
1029e5dd7070Spatrick
1030e5dd7070Spatrick public:
1031e5dd7070Spatrick SwitchConvertDiagnoser(Expr *Cond)
1032e5dd7070Spatrick : ICEConvertDiagnoser(/*AllowScopedEnumerations*/true, false, true),
1033e5dd7070Spatrick Cond(Cond) {}
1034e5dd7070Spatrick
1035e5dd7070Spatrick SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
1036e5dd7070Spatrick QualType T) override {
1037e5dd7070Spatrick return S.Diag(Loc, diag::err_typecheck_statement_requires_integer) << T;
1038e5dd7070Spatrick }
1039e5dd7070Spatrick
1040e5dd7070Spatrick SemaDiagnosticBuilder diagnoseIncomplete(
1041e5dd7070Spatrick Sema &S, SourceLocation Loc, QualType T) override {
1042e5dd7070Spatrick return S.Diag(Loc, diag::err_switch_incomplete_class_type)
1043e5dd7070Spatrick << T << Cond->getSourceRange();
1044e5dd7070Spatrick }
1045e5dd7070Spatrick
1046e5dd7070Spatrick SemaDiagnosticBuilder diagnoseExplicitConv(
1047e5dd7070Spatrick Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
1048e5dd7070Spatrick return S.Diag(Loc, diag::err_switch_explicit_conversion) << T << ConvTy;
1049e5dd7070Spatrick }
1050e5dd7070Spatrick
1051e5dd7070Spatrick SemaDiagnosticBuilder noteExplicitConv(
1052e5dd7070Spatrick Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1053e5dd7070Spatrick return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
1054e5dd7070Spatrick << ConvTy->isEnumeralType() << ConvTy;
1055e5dd7070Spatrick }
1056e5dd7070Spatrick
1057e5dd7070Spatrick SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
1058e5dd7070Spatrick QualType T) override {
1059e5dd7070Spatrick return S.Diag(Loc, diag::err_switch_multiple_conversions) << T;
1060e5dd7070Spatrick }
1061e5dd7070Spatrick
1062e5dd7070Spatrick SemaDiagnosticBuilder noteAmbiguous(
1063e5dd7070Spatrick Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1064e5dd7070Spatrick return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
1065e5dd7070Spatrick << ConvTy->isEnumeralType() << ConvTy;
1066e5dd7070Spatrick }
1067e5dd7070Spatrick
1068e5dd7070Spatrick SemaDiagnosticBuilder diagnoseConversion(
1069e5dd7070Spatrick Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
1070e5dd7070Spatrick llvm_unreachable("conversion functions are permitted");
1071e5dd7070Spatrick }
1072e5dd7070Spatrick } SwitchDiagnoser(Cond);
1073e5dd7070Spatrick
1074e5dd7070Spatrick ExprResult CondResult =
1075e5dd7070Spatrick PerformContextualImplicitConversion(SwitchLoc, Cond, SwitchDiagnoser);
1076e5dd7070Spatrick if (CondResult.isInvalid())
1077e5dd7070Spatrick return ExprError();
1078e5dd7070Spatrick
1079e5dd7070Spatrick // FIXME: PerformContextualImplicitConversion doesn't always tell us if it
1080e5dd7070Spatrick // failed and produced a diagnostic.
1081e5dd7070Spatrick Cond = CondResult.get();
1082e5dd7070Spatrick if (!Cond->isTypeDependent() &&
1083e5dd7070Spatrick !Cond->getType()->isIntegralOrEnumerationType())
1084e5dd7070Spatrick return ExprError();
1085e5dd7070Spatrick
1086e5dd7070Spatrick // C99 6.8.4.2p5 - Integer promotions are performed on the controlling expr.
1087e5dd7070Spatrick return UsualUnaryConversions(Cond);
1088e5dd7070Spatrick }
1089e5dd7070Spatrick
ActOnStartOfSwitchStmt(SourceLocation SwitchLoc,SourceLocation LParenLoc,Stmt * InitStmt,ConditionResult Cond,SourceLocation RParenLoc)1090e5dd7070Spatrick StmtResult Sema::ActOnStartOfSwitchStmt(SourceLocation SwitchLoc,
1091a9ac8606Spatrick SourceLocation LParenLoc,
1092a9ac8606Spatrick Stmt *InitStmt, ConditionResult Cond,
1093a9ac8606Spatrick SourceLocation RParenLoc) {
1094e5dd7070Spatrick Expr *CondExpr = Cond.get().second;
1095e5dd7070Spatrick assert((Cond.isInvalid() || CondExpr) && "switch with no condition");
1096e5dd7070Spatrick
1097e5dd7070Spatrick if (CondExpr && !CondExpr->isTypeDependent()) {
1098e5dd7070Spatrick // We have already converted the expression to an integral or enumeration
1099ec727ea7Spatrick // type, when we parsed the switch condition. There are cases where we don't
1100ec727ea7Spatrick // have an appropriate type, e.g. a typo-expr Cond was corrected to an
1101ec727ea7Spatrick // inappropriate-type expr, we just return an error.
1102ec727ea7Spatrick if (!CondExpr->getType()->isIntegralOrEnumerationType())
1103ec727ea7Spatrick return StmtError();
1104e5dd7070Spatrick if (CondExpr->isKnownToHaveBooleanValue()) {
1105e5dd7070Spatrick // switch(bool_expr) {...} is often a programmer error, e.g.
1106e5dd7070Spatrick // switch(n && mask) { ... } // Doh - should be "n & mask".
1107e5dd7070Spatrick // One can always use an if statement instead of switch(bool_expr).
1108e5dd7070Spatrick Diag(SwitchLoc, diag::warn_bool_switch_condition)
1109e5dd7070Spatrick << CondExpr->getSourceRange();
1110e5dd7070Spatrick }
1111e5dd7070Spatrick }
1112e5dd7070Spatrick
1113e5dd7070Spatrick setFunctionHasBranchIntoScope();
1114e5dd7070Spatrick
1115a9ac8606Spatrick auto *SS = SwitchStmt::Create(Context, InitStmt, Cond.get().first, CondExpr,
1116a9ac8606Spatrick LParenLoc, RParenLoc);
1117e5dd7070Spatrick getCurFunction()->SwitchStack.push_back(
1118e5dd7070Spatrick FunctionScopeInfo::SwitchInfo(SS, false));
1119e5dd7070Spatrick return SS;
1120e5dd7070Spatrick }
1121e5dd7070Spatrick
AdjustAPSInt(llvm::APSInt & Val,unsigned BitWidth,bool IsSigned)1122e5dd7070Spatrick static void AdjustAPSInt(llvm::APSInt &Val, unsigned BitWidth, bool IsSigned) {
1123e5dd7070Spatrick Val = Val.extOrTrunc(BitWidth);
1124e5dd7070Spatrick Val.setIsSigned(IsSigned);
1125e5dd7070Spatrick }
1126e5dd7070Spatrick
1127e5dd7070Spatrick /// Check the specified case value is in range for the given unpromoted switch
1128e5dd7070Spatrick /// type.
checkCaseValue(Sema & S,SourceLocation Loc,const llvm::APSInt & Val,unsigned UnpromotedWidth,bool UnpromotedSign)1129e5dd7070Spatrick static void checkCaseValue(Sema &S, SourceLocation Loc, const llvm::APSInt &Val,
1130e5dd7070Spatrick unsigned UnpromotedWidth, bool UnpromotedSign) {
1131e5dd7070Spatrick // In C++11 onwards, this is checked by the language rules.
1132e5dd7070Spatrick if (S.getLangOpts().CPlusPlus11)
1133e5dd7070Spatrick return;
1134e5dd7070Spatrick
1135e5dd7070Spatrick // If the case value was signed and negative and the switch expression is
1136e5dd7070Spatrick // unsigned, don't bother to warn: this is implementation-defined behavior.
1137e5dd7070Spatrick // FIXME: Introduce a second, default-ignored warning for this case?
1138e5dd7070Spatrick if (UnpromotedWidth < Val.getBitWidth()) {
1139e5dd7070Spatrick llvm::APSInt ConvVal(Val);
1140e5dd7070Spatrick AdjustAPSInt(ConvVal, UnpromotedWidth, UnpromotedSign);
1141e5dd7070Spatrick AdjustAPSInt(ConvVal, Val.getBitWidth(), Val.isSigned());
1142e5dd7070Spatrick // FIXME: Use different diagnostics for overflow in conversion to promoted
1143e5dd7070Spatrick // type versus "switch expression cannot have this value". Use proper
1144e5dd7070Spatrick // IntRange checking rather than just looking at the unpromoted type here.
1145e5dd7070Spatrick if (ConvVal != Val)
1146a9ac8606Spatrick S.Diag(Loc, diag::warn_case_value_overflow) << toString(Val, 10)
1147a9ac8606Spatrick << toString(ConvVal, 10);
1148e5dd7070Spatrick }
1149e5dd7070Spatrick }
1150e5dd7070Spatrick
1151e5dd7070Spatrick typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl*>, 64> EnumValsTy;
1152e5dd7070Spatrick
1153e5dd7070Spatrick /// Returns true if we should emit a diagnostic about this case expression not
1154e5dd7070Spatrick /// being a part of the enum used in the switch controlling expression.
ShouldDiagnoseSwitchCaseNotInEnum(const Sema & S,const EnumDecl * ED,const Expr * CaseExpr,EnumValsTy::iterator & EI,EnumValsTy::iterator & EIEnd,const llvm::APSInt & Val)1155e5dd7070Spatrick static bool ShouldDiagnoseSwitchCaseNotInEnum(const Sema &S,
1156e5dd7070Spatrick const EnumDecl *ED,
1157e5dd7070Spatrick const Expr *CaseExpr,
1158e5dd7070Spatrick EnumValsTy::iterator &EI,
1159e5dd7070Spatrick EnumValsTy::iterator &EIEnd,
1160e5dd7070Spatrick const llvm::APSInt &Val) {
1161e5dd7070Spatrick if (!ED->isClosed())
1162e5dd7070Spatrick return false;
1163e5dd7070Spatrick
1164e5dd7070Spatrick if (const DeclRefExpr *DRE =
1165e5dd7070Spatrick dyn_cast<DeclRefExpr>(CaseExpr->IgnoreParenImpCasts())) {
1166e5dd7070Spatrick if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) {
1167e5dd7070Spatrick QualType VarType = VD->getType();
1168e5dd7070Spatrick QualType EnumType = S.Context.getTypeDeclType(ED);
1169e5dd7070Spatrick if (VD->hasGlobalStorage() && VarType.isConstQualified() &&
1170e5dd7070Spatrick S.Context.hasSameUnqualifiedType(EnumType, VarType))
1171e5dd7070Spatrick return false;
1172e5dd7070Spatrick }
1173e5dd7070Spatrick }
1174e5dd7070Spatrick
1175e5dd7070Spatrick if (ED->hasAttr<FlagEnumAttr>())
1176e5dd7070Spatrick return !S.IsValueInFlagEnum(ED, Val, false);
1177e5dd7070Spatrick
1178e5dd7070Spatrick while (EI != EIEnd && EI->first < Val)
1179e5dd7070Spatrick EI++;
1180e5dd7070Spatrick
1181e5dd7070Spatrick if (EI != EIEnd && EI->first == Val)
1182e5dd7070Spatrick return false;
1183e5dd7070Spatrick
1184e5dd7070Spatrick return true;
1185e5dd7070Spatrick }
1186e5dd7070Spatrick
checkEnumTypesInSwitchStmt(Sema & S,const Expr * Cond,const Expr * Case)1187e5dd7070Spatrick static void checkEnumTypesInSwitchStmt(Sema &S, const Expr *Cond,
1188e5dd7070Spatrick const Expr *Case) {
1189e5dd7070Spatrick QualType CondType = Cond->getType();
1190e5dd7070Spatrick QualType CaseType = Case->getType();
1191e5dd7070Spatrick
1192e5dd7070Spatrick const EnumType *CondEnumType = CondType->getAs<EnumType>();
1193e5dd7070Spatrick const EnumType *CaseEnumType = CaseType->getAs<EnumType>();
1194e5dd7070Spatrick if (!CondEnumType || !CaseEnumType)
1195e5dd7070Spatrick return;
1196e5dd7070Spatrick
1197e5dd7070Spatrick // Ignore anonymous enums.
1198e5dd7070Spatrick if (!CondEnumType->getDecl()->getIdentifier() &&
1199e5dd7070Spatrick !CondEnumType->getDecl()->getTypedefNameForAnonDecl())
1200e5dd7070Spatrick return;
1201e5dd7070Spatrick if (!CaseEnumType->getDecl()->getIdentifier() &&
1202e5dd7070Spatrick !CaseEnumType->getDecl()->getTypedefNameForAnonDecl())
1203e5dd7070Spatrick return;
1204e5dd7070Spatrick
1205e5dd7070Spatrick if (S.Context.hasSameUnqualifiedType(CondType, CaseType))
1206e5dd7070Spatrick return;
1207e5dd7070Spatrick
1208e5dd7070Spatrick S.Diag(Case->getExprLoc(), diag::warn_comparison_of_mixed_enum_types_switch)
1209e5dd7070Spatrick << CondType << CaseType << Cond->getSourceRange()
1210e5dd7070Spatrick << Case->getSourceRange();
1211e5dd7070Spatrick }
1212e5dd7070Spatrick
1213e5dd7070Spatrick StmtResult
ActOnFinishSwitchStmt(SourceLocation SwitchLoc,Stmt * Switch,Stmt * BodyStmt)1214e5dd7070Spatrick Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch,
1215e5dd7070Spatrick Stmt *BodyStmt) {
1216e5dd7070Spatrick SwitchStmt *SS = cast<SwitchStmt>(Switch);
1217e5dd7070Spatrick bool CaseListIsIncomplete = getCurFunction()->SwitchStack.back().getInt();
1218e5dd7070Spatrick assert(SS == getCurFunction()->SwitchStack.back().getPointer() &&
1219e5dd7070Spatrick "switch stack missing push/pop!");
1220e5dd7070Spatrick
1221e5dd7070Spatrick getCurFunction()->SwitchStack.pop_back();
1222e5dd7070Spatrick
1223e5dd7070Spatrick if (!BodyStmt) return StmtError();
1224e5dd7070Spatrick SS->setBody(BodyStmt, SwitchLoc);
1225e5dd7070Spatrick
1226e5dd7070Spatrick Expr *CondExpr = SS->getCond();
1227e5dd7070Spatrick if (!CondExpr) return StmtError();
1228e5dd7070Spatrick
1229e5dd7070Spatrick QualType CondType = CondExpr->getType();
1230e5dd7070Spatrick
1231e5dd7070Spatrick // C++ 6.4.2.p2:
1232e5dd7070Spatrick // Integral promotions are performed (on the switch condition).
1233e5dd7070Spatrick //
1234e5dd7070Spatrick // A case value unrepresentable by the original switch condition
1235e5dd7070Spatrick // type (before the promotion) doesn't make sense, even when it can
1236e5dd7070Spatrick // be represented by the promoted type. Therefore we need to find
1237e5dd7070Spatrick // the pre-promotion type of the switch condition.
1238e5dd7070Spatrick const Expr *CondExprBeforePromotion = CondExpr;
1239e5dd7070Spatrick QualType CondTypeBeforePromotion =
1240e5dd7070Spatrick GetTypeBeforeIntegralPromotion(CondExprBeforePromotion);
1241e5dd7070Spatrick
1242e5dd7070Spatrick // Get the bitwidth of the switched-on value after promotions. We must
1243e5dd7070Spatrick // convert the integer case values to this width before comparison.
1244e5dd7070Spatrick bool HasDependentValue
1245e5dd7070Spatrick = CondExpr->isTypeDependent() || CondExpr->isValueDependent();
1246e5dd7070Spatrick unsigned CondWidth = HasDependentValue ? 0 : Context.getIntWidth(CondType);
1247e5dd7070Spatrick bool CondIsSigned = CondType->isSignedIntegerOrEnumerationType();
1248e5dd7070Spatrick
1249e5dd7070Spatrick // Get the width and signedness that the condition might actually have, for
1250e5dd7070Spatrick // warning purposes.
1251e5dd7070Spatrick // FIXME: Grab an IntRange for the condition rather than using the unpromoted
1252e5dd7070Spatrick // type.
1253e5dd7070Spatrick unsigned CondWidthBeforePromotion
1254e5dd7070Spatrick = HasDependentValue ? 0 : Context.getIntWidth(CondTypeBeforePromotion);
1255e5dd7070Spatrick bool CondIsSignedBeforePromotion
1256e5dd7070Spatrick = CondTypeBeforePromotion->isSignedIntegerOrEnumerationType();
1257e5dd7070Spatrick
1258e5dd7070Spatrick // Accumulate all of the case values in a vector so that we can sort them
1259e5dd7070Spatrick // and detect duplicates. This vector contains the APInt for the case after
1260e5dd7070Spatrick // it has been converted to the condition type.
1261e5dd7070Spatrick typedef SmallVector<std::pair<llvm::APSInt, CaseStmt*>, 64> CaseValsTy;
1262e5dd7070Spatrick CaseValsTy CaseVals;
1263e5dd7070Spatrick
1264e5dd7070Spatrick // Keep track of any GNU case ranges we see. The APSInt is the low value.
1265e5dd7070Spatrick typedef std::vector<std::pair<llvm::APSInt, CaseStmt*> > CaseRangesTy;
1266e5dd7070Spatrick CaseRangesTy CaseRanges;
1267e5dd7070Spatrick
1268e5dd7070Spatrick DefaultStmt *TheDefaultStmt = nullptr;
1269e5dd7070Spatrick
1270e5dd7070Spatrick bool CaseListIsErroneous = false;
1271e5dd7070Spatrick
1272e5dd7070Spatrick for (SwitchCase *SC = SS->getSwitchCaseList(); SC && !HasDependentValue;
1273e5dd7070Spatrick SC = SC->getNextSwitchCase()) {
1274e5dd7070Spatrick
1275e5dd7070Spatrick if (DefaultStmt *DS = dyn_cast<DefaultStmt>(SC)) {
1276e5dd7070Spatrick if (TheDefaultStmt) {
1277e5dd7070Spatrick Diag(DS->getDefaultLoc(), diag::err_multiple_default_labels_defined);
1278e5dd7070Spatrick Diag(TheDefaultStmt->getDefaultLoc(), diag::note_duplicate_case_prev);
1279e5dd7070Spatrick
1280e5dd7070Spatrick // FIXME: Remove the default statement from the switch block so that
1281e5dd7070Spatrick // we'll return a valid AST. This requires recursing down the AST and
1282e5dd7070Spatrick // finding it, not something we are set up to do right now. For now,
1283e5dd7070Spatrick // just lop the entire switch stmt out of the AST.
1284e5dd7070Spatrick CaseListIsErroneous = true;
1285e5dd7070Spatrick }
1286e5dd7070Spatrick TheDefaultStmt = DS;
1287e5dd7070Spatrick
1288e5dd7070Spatrick } else {
1289e5dd7070Spatrick CaseStmt *CS = cast<CaseStmt>(SC);
1290e5dd7070Spatrick
1291e5dd7070Spatrick Expr *Lo = CS->getLHS();
1292e5dd7070Spatrick
1293e5dd7070Spatrick if (Lo->isValueDependent()) {
1294e5dd7070Spatrick HasDependentValue = true;
1295e5dd7070Spatrick break;
1296e5dd7070Spatrick }
1297e5dd7070Spatrick
1298e5dd7070Spatrick // We already verified that the expression has a constant value;
1299e5dd7070Spatrick // get that value (prior to conversions).
1300e5dd7070Spatrick const Expr *LoBeforePromotion = Lo;
1301e5dd7070Spatrick GetTypeBeforeIntegralPromotion(LoBeforePromotion);
1302e5dd7070Spatrick llvm::APSInt LoVal = LoBeforePromotion->EvaluateKnownConstInt(Context);
1303e5dd7070Spatrick
1304e5dd7070Spatrick // Check the unconverted value is within the range of possible values of
1305e5dd7070Spatrick // the switch expression.
1306e5dd7070Spatrick checkCaseValue(*this, Lo->getBeginLoc(), LoVal, CondWidthBeforePromotion,
1307e5dd7070Spatrick CondIsSignedBeforePromotion);
1308e5dd7070Spatrick
1309e5dd7070Spatrick // FIXME: This duplicates the check performed for warn_not_in_enum below.
1310e5dd7070Spatrick checkEnumTypesInSwitchStmt(*this, CondExprBeforePromotion,
1311e5dd7070Spatrick LoBeforePromotion);
1312e5dd7070Spatrick
1313e5dd7070Spatrick // Convert the value to the same width/sign as the condition.
1314e5dd7070Spatrick AdjustAPSInt(LoVal, CondWidth, CondIsSigned);
1315e5dd7070Spatrick
1316e5dd7070Spatrick // If this is a case range, remember it in CaseRanges, otherwise CaseVals.
1317e5dd7070Spatrick if (CS->getRHS()) {
1318e5dd7070Spatrick if (CS->getRHS()->isValueDependent()) {
1319e5dd7070Spatrick HasDependentValue = true;
1320e5dd7070Spatrick break;
1321e5dd7070Spatrick }
1322e5dd7070Spatrick CaseRanges.push_back(std::make_pair(LoVal, CS));
1323e5dd7070Spatrick } else
1324e5dd7070Spatrick CaseVals.push_back(std::make_pair(LoVal, CS));
1325e5dd7070Spatrick }
1326e5dd7070Spatrick }
1327e5dd7070Spatrick
1328e5dd7070Spatrick if (!HasDependentValue) {
1329e5dd7070Spatrick // If we don't have a default statement, check whether the
1330e5dd7070Spatrick // condition is constant.
1331e5dd7070Spatrick llvm::APSInt ConstantCondValue;
1332e5dd7070Spatrick bool HasConstantCond = false;
1333e5dd7070Spatrick if (!TheDefaultStmt) {
1334e5dd7070Spatrick Expr::EvalResult Result;
1335e5dd7070Spatrick HasConstantCond = CondExpr->EvaluateAsInt(Result, Context,
1336e5dd7070Spatrick Expr::SE_AllowSideEffects);
1337e5dd7070Spatrick if (Result.Val.isInt())
1338e5dd7070Spatrick ConstantCondValue = Result.Val.getInt();
1339e5dd7070Spatrick assert(!HasConstantCond ||
1340e5dd7070Spatrick (ConstantCondValue.getBitWidth() == CondWidth &&
1341e5dd7070Spatrick ConstantCondValue.isSigned() == CondIsSigned));
1342e5dd7070Spatrick }
1343e5dd7070Spatrick bool ShouldCheckConstantCond = HasConstantCond;
1344e5dd7070Spatrick
1345e5dd7070Spatrick // Sort all the scalar case values so we can easily detect duplicates.
1346e5dd7070Spatrick llvm::stable_sort(CaseVals, CmpCaseVals);
1347e5dd7070Spatrick
1348e5dd7070Spatrick if (!CaseVals.empty()) {
1349e5dd7070Spatrick for (unsigned i = 0, e = CaseVals.size(); i != e; ++i) {
1350e5dd7070Spatrick if (ShouldCheckConstantCond &&
1351e5dd7070Spatrick CaseVals[i].first == ConstantCondValue)
1352e5dd7070Spatrick ShouldCheckConstantCond = false;
1353e5dd7070Spatrick
1354e5dd7070Spatrick if (i != 0 && CaseVals[i].first == CaseVals[i-1].first) {
1355e5dd7070Spatrick // If we have a duplicate, report it.
1356e5dd7070Spatrick // First, determine if either case value has a name
1357e5dd7070Spatrick StringRef PrevString, CurrString;
1358e5dd7070Spatrick Expr *PrevCase = CaseVals[i-1].second->getLHS()->IgnoreParenCasts();
1359e5dd7070Spatrick Expr *CurrCase = CaseVals[i].second->getLHS()->IgnoreParenCasts();
1360e5dd7070Spatrick if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(PrevCase)) {
1361e5dd7070Spatrick PrevString = DeclRef->getDecl()->getName();
1362e5dd7070Spatrick }
1363e5dd7070Spatrick if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(CurrCase)) {
1364e5dd7070Spatrick CurrString = DeclRef->getDecl()->getName();
1365e5dd7070Spatrick }
1366e5dd7070Spatrick SmallString<16> CaseValStr;
1367e5dd7070Spatrick CaseVals[i-1].first.toString(CaseValStr);
1368e5dd7070Spatrick
1369e5dd7070Spatrick if (PrevString == CurrString)
1370e5dd7070Spatrick Diag(CaseVals[i].second->getLHS()->getBeginLoc(),
1371e5dd7070Spatrick diag::err_duplicate_case)
1372a9ac8606Spatrick << (PrevString.empty() ? CaseValStr.str() : PrevString);
1373e5dd7070Spatrick else
1374e5dd7070Spatrick Diag(CaseVals[i].second->getLHS()->getBeginLoc(),
1375e5dd7070Spatrick diag::err_duplicate_case_differing_expr)
1376a9ac8606Spatrick << (PrevString.empty() ? CaseValStr.str() : PrevString)
1377a9ac8606Spatrick << (CurrString.empty() ? CaseValStr.str() : CurrString)
1378e5dd7070Spatrick << CaseValStr;
1379e5dd7070Spatrick
1380e5dd7070Spatrick Diag(CaseVals[i - 1].second->getLHS()->getBeginLoc(),
1381e5dd7070Spatrick diag::note_duplicate_case_prev);
1382e5dd7070Spatrick // FIXME: We really want to remove the bogus case stmt from the
1383e5dd7070Spatrick // substmt, but we have no way to do this right now.
1384e5dd7070Spatrick CaseListIsErroneous = true;
1385e5dd7070Spatrick }
1386e5dd7070Spatrick }
1387e5dd7070Spatrick }
1388e5dd7070Spatrick
1389e5dd7070Spatrick // Detect duplicate case ranges, which usually don't exist at all in
1390e5dd7070Spatrick // the first place.
1391e5dd7070Spatrick if (!CaseRanges.empty()) {
1392e5dd7070Spatrick // Sort all the case ranges by their low value so we can easily detect
1393e5dd7070Spatrick // overlaps between ranges.
1394e5dd7070Spatrick llvm::stable_sort(CaseRanges);
1395e5dd7070Spatrick
1396e5dd7070Spatrick // Scan the ranges, computing the high values and removing empty ranges.
1397e5dd7070Spatrick std::vector<llvm::APSInt> HiVals;
1398e5dd7070Spatrick for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
1399e5dd7070Spatrick llvm::APSInt &LoVal = CaseRanges[i].first;
1400e5dd7070Spatrick CaseStmt *CR = CaseRanges[i].second;
1401e5dd7070Spatrick Expr *Hi = CR->getRHS();
1402e5dd7070Spatrick
1403e5dd7070Spatrick const Expr *HiBeforePromotion = Hi;
1404e5dd7070Spatrick GetTypeBeforeIntegralPromotion(HiBeforePromotion);
1405e5dd7070Spatrick llvm::APSInt HiVal = HiBeforePromotion->EvaluateKnownConstInt(Context);
1406e5dd7070Spatrick
1407e5dd7070Spatrick // Check the unconverted value is within the range of possible values of
1408e5dd7070Spatrick // the switch expression.
1409e5dd7070Spatrick checkCaseValue(*this, Hi->getBeginLoc(), HiVal,
1410e5dd7070Spatrick CondWidthBeforePromotion, CondIsSignedBeforePromotion);
1411e5dd7070Spatrick
1412e5dd7070Spatrick // Convert the value to the same width/sign as the condition.
1413e5dd7070Spatrick AdjustAPSInt(HiVal, CondWidth, CondIsSigned);
1414e5dd7070Spatrick
1415e5dd7070Spatrick // If the low value is bigger than the high value, the case is empty.
1416e5dd7070Spatrick if (LoVal > HiVal) {
1417e5dd7070Spatrick Diag(CR->getLHS()->getBeginLoc(), diag::warn_case_empty_range)
1418e5dd7070Spatrick << SourceRange(CR->getLHS()->getBeginLoc(), Hi->getEndLoc());
1419e5dd7070Spatrick CaseRanges.erase(CaseRanges.begin()+i);
1420e5dd7070Spatrick --i;
1421e5dd7070Spatrick --e;
1422e5dd7070Spatrick continue;
1423e5dd7070Spatrick }
1424e5dd7070Spatrick
1425e5dd7070Spatrick if (ShouldCheckConstantCond &&
1426e5dd7070Spatrick LoVal <= ConstantCondValue &&
1427e5dd7070Spatrick ConstantCondValue <= HiVal)
1428e5dd7070Spatrick ShouldCheckConstantCond = false;
1429e5dd7070Spatrick
1430e5dd7070Spatrick HiVals.push_back(HiVal);
1431e5dd7070Spatrick }
1432e5dd7070Spatrick
1433e5dd7070Spatrick // Rescan the ranges, looking for overlap with singleton values and other
1434e5dd7070Spatrick // ranges. Since the range list is sorted, we only need to compare case
1435e5dd7070Spatrick // ranges with their neighbors.
1436e5dd7070Spatrick for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
1437e5dd7070Spatrick llvm::APSInt &CRLo = CaseRanges[i].first;
1438e5dd7070Spatrick llvm::APSInt &CRHi = HiVals[i];
1439e5dd7070Spatrick CaseStmt *CR = CaseRanges[i].second;
1440e5dd7070Spatrick
1441e5dd7070Spatrick // Check to see whether the case range overlaps with any
1442e5dd7070Spatrick // singleton cases.
1443e5dd7070Spatrick CaseStmt *OverlapStmt = nullptr;
1444e5dd7070Spatrick llvm::APSInt OverlapVal(32);
1445e5dd7070Spatrick
1446e5dd7070Spatrick // Find the smallest value >= the lower bound. If I is in the
1447e5dd7070Spatrick // case range, then we have overlap.
1448e5dd7070Spatrick CaseValsTy::iterator I =
1449e5dd7070Spatrick llvm::lower_bound(CaseVals, CRLo, CaseCompareFunctor());
1450e5dd7070Spatrick if (I != CaseVals.end() && I->first < CRHi) {
1451e5dd7070Spatrick OverlapVal = I->first; // Found overlap with scalar.
1452e5dd7070Spatrick OverlapStmt = I->second;
1453e5dd7070Spatrick }
1454e5dd7070Spatrick
1455e5dd7070Spatrick // Find the smallest value bigger than the upper bound.
1456e5dd7070Spatrick I = std::upper_bound(I, CaseVals.end(), CRHi, CaseCompareFunctor());
1457e5dd7070Spatrick if (I != CaseVals.begin() && (I-1)->first >= CRLo) {
1458e5dd7070Spatrick OverlapVal = (I-1)->first; // Found overlap with scalar.
1459e5dd7070Spatrick OverlapStmt = (I-1)->second;
1460e5dd7070Spatrick }
1461e5dd7070Spatrick
1462e5dd7070Spatrick // Check to see if this case stmt overlaps with the subsequent
1463e5dd7070Spatrick // case range.
1464e5dd7070Spatrick if (i && CRLo <= HiVals[i-1]) {
1465e5dd7070Spatrick OverlapVal = HiVals[i-1]; // Found overlap with range.
1466e5dd7070Spatrick OverlapStmt = CaseRanges[i-1].second;
1467e5dd7070Spatrick }
1468e5dd7070Spatrick
1469e5dd7070Spatrick if (OverlapStmt) {
1470e5dd7070Spatrick // If we have a duplicate, report it.
1471e5dd7070Spatrick Diag(CR->getLHS()->getBeginLoc(), diag::err_duplicate_case)
1472a9ac8606Spatrick << toString(OverlapVal, 10);
1473e5dd7070Spatrick Diag(OverlapStmt->getLHS()->getBeginLoc(),
1474e5dd7070Spatrick diag::note_duplicate_case_prev);
1475e5dd7070Spatrick // FIXME: We really want to remove the bogus case stmt from the
1476e5dd7070Spatrick // substmt, but we have no way to do this right now.
1477e5dd7070Spatrick CaseListIsErroneous = true;
1478e5dd7070Spatrick }
1479e5dd7070Spatrick }
1480e5dd7070Spatrick }
1481e5dd7070Spatrick
1482e5dd7070Spatrick // Complain if we have a constant condition and we didn't find a match.
1483e5dd7070Spatrick if (!CaseListIsErroneous && !CaseListIsIncomplete &&
1484e5dd7070Spatrick ShouldCheckConstantCond) {
1485e5dd7070Spatrick // TODO: it would be nice if we printed enums as enums, chars as
1486e5dd7070Spatrick // chars, etc.
1487e5dd7070Spatrick Diag(CondExpr->getExprLoc(), diag::warn_missing_case_for_condition)
1488a9ac8606Spatrick << toString(ConstantCondValue, 10)
1489e5dd7070Spatrick << CondExpr->getSourceRange();
1490e5dd7070Spatrick }
1491e5dd7070Spatrick
1492e5dd7070Spatrick // Check to see if switch is over an Enum and handles all of its
1493e5dd7070Spatrick // values. We only issue a warning if there is not 'default:', but
1494e5dd7070Spatrick // we still do the analysis to preserve this information in the AST
1495e5dd7070Spatrick // (which can be used by flow-based analyes).
1496e5dd7070Spatrick //
1497e5dd7070Spatrick const EnumType *ET = CondTypeBeforePromotion->getAs<EnumType>();
1498e5dd7070Spatrick
1499e5dd7070Spatrick // If switch has default case, then ignore it.
1500e5dd7070Spatrick if (!CaseListIsErroneous && !CaseListIsIncomplete && !HasConstantCond &&
1501a9ac8606Spatrick ET && ET->getDecl()->isCompleteDefinition() &&
1502*12c85518Srobert !ET->getDecl()->enumerators().empty()) {
1503e5dd7070Spatrick const EnumDecl *ED = ET->getDecl();
1504e5dd7070Spatrick EnumValsTy EnumVals;
1505e5dd7070Spatrick
1506e5dd7070Spatrick // Gather all enum values, set their type and sort them,
1507e5dd7070Spatrick // allowing easier comparison with CaseVals.
1508e5dd7070Spatrick for (auto *EDI : ED->enumerators()) {
1509e5dd7070Spatrick llvm::APSInt Val = EDI->getInitVal();
1510e5dd7070Spatrick AdjustAPSInt(Val, CondWidth, CondIsSigned);
1511e5dd7070Spatrick EnumVals.push_back(std::make_pair(Val, EDI));
1512e5dd7070Spatrick }
1513e5dd7070Spatrick llvm::stable_sort(EnumVals, CmpEnumVals);
1514e5dd7070Spatrick auto EI = EnumVals.begin(), EIEnd =
1515e5dd7070Spatrick std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals);
1516e5dd7070Spatrick
1517e5dd7070Spatrick // See which case values aren't in enum.
1518e5dd7070Spatrick for (CaseValsTy::const_iterator CI = CaseVals.begin();
1519e5dd7070Spatrick CI != CaseVals.end(); CI++) {
1520e5dd7070Spatrick Expr *CaseExpr = CI->second->getLHS();
1521e5dd7070Spatrick if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd,
1522e5dd7070Spatrick CI->first))
1523e5dd7070Spatrick Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum)
1524e5dd7070Spatrick << CondTypeBeforePromotion;
1525e5dd7070Spatrick }
1526e5dd7070Spatrick
1527e5dd7070Spatrick // See which of case ranges aren't in enum
1528e5dd7070Spatrick EI = EnumVals.begin();
1529e5dd7070Spatrick for (CaseRangesTy::const_iterator RI = CaseRanges.begin();
1530e5dd7070Spatrick RI != CaseRanges.end(); RI++) {
1531e5dd7070Spatrick Expr *CaseExpr = RI->second->getLHS();
1532e5dd7070Spatrick if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd,
1533e5dd7070Spatrick RI->first))
1534e5dd7070Spatrick Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum)
1535e5dd7070Spatrick << CondTypeBeforePromotion;
1536e5dd7070Spatrick
1537e5dd7070Spatrick llvm::APSInt Hi =
1538e5dd7070Spatrick RI->second->getRHS()->EvaluateKnownConstInt(Context);
1539e5dd7070Spatrick AdjustAPSInt(Hi, CondWidth, CondIsSigned);
1540e5dd7070Spatrick
1541e5dd7070Spatrick CaseExpr = RI->second->getRHS();
1542e5dd7070Spatrick if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd,
1543e5dd7070Spatrick Hi))
1544e5dd7070Spatrick Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum)
1545e5dd7070Spatrick << CondTypeBeforePromotion;
1546e5dd7070Spatrick }
1547e5dd7070Spatrick
1548e5dd7070Spatrick // Check which enum vals aren't in switch
1549e5dd7070Spatrick auto CI = CaseVals.begin();
1550e5dd7070Spatrick auto RI = CaseRanges.begin();
1551e5dd7070Spatrick bool hasCasesNotInSwitch = false;
1552e5dd7070Spatrick
1553e5dd7070Spatrick SmallVector<DeclarationName,8> UnhandledNames;
1554e5dd7070Spatrick
1555e5dd7070Spatrick for (EI = EnumVals.begin(); EI != EIEnd; EI++) {
1556e5dd7070Spatrick // Don't warn about omitted unavailable EnumConstantDecls.
1557e5dd7070Spatrick switch (EI->second->getAvailability()) {
1558e5dd7070Spatrick case AR_Deprecated:
1559e5dd7070Spatrick // Omitting a deprecated constant is ok; it should never materialize.
1560e5dd7070Spatrick case AR_Unavailable:
1561e5dd7070Spatrick continue;
1562e5dd7070Spatrick
1563e5dd7070Spatrick case AR_NotYetIntroduced:
1564e5dd7070Spatrick // Partially available enum constants should be present. Note that we
1565e5dd7070Spatrick // suppress -Wunguarded-availability diagnostics for such uses.
1566e5dd7070Spatrick case AR_Available:
1567e5dd7070Spatrick break;
1568e5dd7070Spatrick }
1569e5dd7070Spatrick
1570e5dd7070Spatrick if (EI->second->hasAttr<UnusedAttr>())
1571e5dd7070Spatrick continue;
1572e5dd7070Spatrick
1573e5dd7070Spatrick // Drop unneeded case values
1574e5dd7070Spatrick while (CI != CaseVals.end() && CI->first < EI->first)
1575e5dd7070Spatrick CI++;
1576e5dd7070Spatrick
1577e5dd7070Spatrick if (CI != CaseVals.end() && CI->first == EI->first)
1578e5dd7070Spatrick continue;
1579e5dd7070Spatrick
1580e5dd7070Spatrick // Drop unneeded case ranges
1581e5dd7070Spatrick for (; RI != CaseRanges.end(); RI++) {
1582e5dd7070Spatrick llvm::APSInt Hi =
1583e5dd7070Spatrick RI->second->getRHS()->EvaluateKnownConstInt(Context);
1584e5dd7070Spatrick AdjustAPSInt(Hi, CondWidth, CondIsSigned);
1585e5dd7070Spatrick if (EI->first <= Hi)
1586e5dd7070Spatrick break;
1587e5dd7070Spatrick }
1588e5dd7070Spatrick
1589e5dd7070Spatrick if (RI == CaseRanges.end() || EI->first < RI->first) {
1590e5dd7070Spatrick hasCasesNotInSwitch = true;
1591e5dd7070Spatrick UnhandledNames.push_back(EI->second->getDeclName());
1592e5dd7070Spatrick }
1593e5dd7070Spatrick }
1594e5dd7070Spatrick
1595e5dd7070Spatrick if (TheDefaultStmt && UnhandledNames.empty() && ED->isClosedNonFlag())
1596e5dd7070Spatrick Diag(TheDefaultStmt->getDefaultLoc(), diag::warn_unreachable_default);
1597e5dd7070Spatrick
1598e5dd7070Spatrick // Produce a nice diagnostic if multiple values aren't handled.
1599e5dd7070Spatrick if (!UnhandledNames.empty()) {
1600a9ac8606Spatrick auto DB = Diag(CondExpr->getExprLoc(), TheDefaultStmt
1601a9ac8606Spatrick ? diag::warn_def_missing_case
1602e5dd7070Spatrick : diag::warn_missing_case)
1603*12c85518Srobert << CondExpr->getSourceRange() << (int)UnhandledNames.size();
1604e5dd7070Spatrick
1605e5dd7070Spatrick for (size_t I = 0, E = std::min(UnhandledNames.size(), (size_t)3);
1606e5dd7070Spatrick I != E; ++I)
1607e5dd7070Spatrick DB << UnhandledNames[I];
1608e5dd7070Spatrick }
1609e5dd7070Spatrick
1610e5dd7070Spatrick if (!hasCasesNotInSwitch)
1611e5dd7070Spatrick SS->setAllEnumCasesCovered();
1612e5dd7070Spatrick }
1613e5dd7070Spatrick }
1614e5dd7070Spatrick
1615e5dd7070Spatrick if (BodyStmt)
1616e5dd7070Spatrick DiagnoseEmptyStmtBody(CondExpr->getEndLoc(), BodyStmt,
1617e5dd7070Spatrick diag::warn_empty_switch_body);
1618e5dd7070Spatrick
1619e5dd7070Spatrick // FIXME: If the case list was broken is some way, we don't have a good system
1620e5dd7070Spatrick // to patch it up. Instead, just return the whole substmt as broken.
1621e5dd7070Spatrick if (CaseListIsErroneous)
1622e5dd7070Spatrick return StmtError();
1623e5dd7070Spatrick
1624e5dd7070Spatrick return SS;
1625e5dd7070Spatrick }
1626e5dd7070Spatrick
1627e5dd7070Spatrick void
DiagnoseAssignmentEnum(QualType DstType,QualType SrcType,Expr * SrcExpr)1628e5dd7070Spatrick Sema::DiagnoseAssignmentEnum(QualType DstType, QualType SrcType,
1629e5dd7070Spatrick Expr *SrcExpr) {
1630e5dd7070Spatrick if (Diags.isIgnored(diag::warn_not_in_enum_assignment, SrcExpr->getExprLoc()))
1631e5dd7070Spatrick return;
1632e5dd7070Spatrick
1633e5dd7070Spatrick if (const EnumType *ET = DstType->getAs<EnumType>())
1634e5dd7070Spatrick if (!Context.hasSameUnqualifiedType(SrcType, DstType) &&
1635e5dd7070Spatrick SrcType->isIntegerType()) {
1636e5dd7070Spatrick if (!SrcExpr->isTypeDependent() && !SrcExpr->isValueDependent() &&
1637e5dd7070Spatrick SrcExpr->isIntegerConstantExpr(Context)) {
1638e5dd7070Spatrick // Get the bitwidth of the enum value before promotions.
1639e5dd7070Spatrick unsigned DstWidth = Context.getIntWidth(DstType);
1640e5dd7070Spatrick bool DstIsSigned = DstType->isSignedIntegerOrEnumerationType();
1641e5dd7070Spatrick
1642e5dd7070Spatrick llvm::APSInt RhsVal = SrcExpr->EvaluateKnownConstInt(Context);
1643e5dd7070Spatrick AdjustAPSInt(RhsVal, DstWidth, DstIsSigned);
1644e5dd7070Spatrick const EnumDecl *ED = ET->getDecl();
1645e5dd7070Spatrick
1646e5dd7070Spatrick if (!ED->isClosed())
1647e5dd7070Spatrick return;
1648e5dd7070Spatrick
1649e5dd7070Spatrick if (ED->hasAttr<FlagEnumAttr>()) {
1650e5dd7070Spatrick if (!IsValueInFlagEnum(ED, RhsVal, true))
1651e5dd7070Spatrick Diag(SrcExpr->getExprLoc(), diag::warn_not_in_enum_assignment)
1652e5dd7070Spatrick << DstType.getUnqualifiedType();
1653e5dd7070Spatrick } else {
1654e5dd7070Spatrick typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl *>, 64>
1655e5dd7070Spatrick EnumValsTy;
1656e5dd7070Spatrick EnumValsTy EnumVals;
1657e5dd7070Spatrick
1658e5dd7070Spatrick // Gather all enum values, set their type and sort them,
1659e5dd7070Spatrick // allowing easier comparison with rhs constant.
1660e5dd7070Spatrick for (auto *EDI : ED->enumerators()) {
1661e5dd7070Spatrick llvm::APSInt Val = EDI->getInitVal();
1662e5dd7070Spatrick AdjustAPSInt(Val, DstWidth, DstIsSigned);
1663e5dd7070Spatrick EnumVals.push_back(std::make_pair(Val, EDI));
1664e5dd7070Spatrick }
1665e5dd7070Spatrick if (EnumVals.empty())
1666e5dd7070Spatrick return;
1667e5dd7070Spatrick llvm::stable_sort(EnumVals, CmpEnumVals);
1668e5dd7070Spatrick EnumValsTy::iterator EIend =
1669e5dd7070Spatrick std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals);
1670e5dd7070Spatrick
1671e5dd7070Spatrick // See which values aren't in the enum.
1672e5dd7070Spatrick EnumValsTy::const_iterator EI = EnumVals.begin();
1673e5dd7070Spatrick while (EI != EIend && EI->first < RhsVal)
1674e5dd7070Spatrick EI++;
1675e5dd7070Spatrick if (EI == EIend || EI->first != RhsVal) {
1676e5dd7070Spatrick Diag(SrcExpr->getExprLoc(), diag::warn_not_in_enum_assignment)
1677e5dd7070Spatrick << DstType.getUnqualifiedType();
1678e5dd7070Spatrick }
1679e5dd7070Spatrick }
1680e5dd7070Spatrick }
1681e5dd7070Spatrick }
1682e5dd7070Spatrick }
1683e5dd7070Spatrick
ActOnWhileStmt(SourceLocation WhileLoc,SourceLocation LParenLoc,ConditionResult Cond,SourceLocation RParenLoc,Stmt * Body)1684ec727ea7Spatrick StmtResult Sema::ActOnWhileStmt(SourceLocation WhileLoc,
1685ec727ea7Spatrick SourceLocation LParenLoc, ConditionResult Cond,
1686ec727ea7Spatrick SourceLocation RParenLoc, Stmt *Body) {
1687e5dd7070Spatrick if (Cond.isInvalid())
1688e5dd7070Spatrick return StmtError();
1689e5dd7070Spatrick
1690e5dd7070Spatrick auto CondVal = Cond.get();
1691e5dd7070Spatrick CheckBreakContinueBinding(CondVal.second);
1692e5dd7070Spatrick
1693e5dd7070Spatrick if (CondVal.second &&
1694e5dd7070Spatrick !Diags.isIgnored(diag::warn_comma_operator, CondVal.second->getExprLoc()))
1695e5dd7070Spatrick CommaVisitor(*this).Visit(CondVal.second);
1696e5dd7070Spatrick
1697e5dd7070Spatrick if (isa<NullStmt>(Body))
1698e5dd7070Spatrick getCurCompoundScope().setHasEmptyLoopBodies();
1699e5dd7070Spatrick
1700e5dd7070Spatrick return WhileStmt::Create(Context, CondVal.first, CondVal.second, Body,
1701ec727ea7Spatrick WhileLoc, LParenLoc, RParenLoc);
1702e5dd7070Spatrick }
1703e5dd7070Spatrick
1704e5dd7070Spatrick StmtResult
ActOnDoStmt(SourceLocation DoLoc,Stmt * Body,SourceLocation WhileLoc,SourceLocation CondLParen,Expr * Cond,SourceLocation CondRParen)1705e5dd7070Spatrick Sema::ActOnDoStmt(SourceLocation DoLoc, Stmt *Body,
1706e5dd7070Spatrick SourceLocation WhileLoc, SourceLocation CondLParen,
1707e5dd7070Spatrick Expr *Cond, SourceLocation CondRParen) {
1708e5dd7070Spatrick assert(Cond && "ActOnDoStmt(): missing expression");
1709e5dd7070Spatrick
1710e5dd7070Spatrick CheckBreakContinueBinding(Cond);
1711e5dd7070Spatrick ExprResult CondResult = CheckBooleanCondition(DoLoc, Cond);
1712e5dd7070Spatrick if (CondResult.isInvalid())
1713e5dd7070Spatrick return StmtError();
1714e5dd7070Spatrick Cond = CondResult.get();
1715e5dd7070Spatrick
1716e5dd7070Spatrick CondResult = ActOnFinishFullExpr(Cond, DoLoc, /*DiscardedValue*/ false);
1717e5dd7070Spatrick if (CondResult.isInvalid())
1718e5dd7070Spatrick return StmtError();
1719e5dd7070Spatrick Cond = CondResult.get();
1720e5dd7070Spatrick
1721e5dd7070Spatrick // Only call the CommaVisitor for C89 due to differences in scope flags.
1722e5dd7070Spatrick if (Cond && !getLangOpts().C99 && !getLangOpts().CPlusPlus &&
1723e5dd7070Spatrick !Diags.isIgnored(diag::warn_comma_operator, Cond->getExprLoc()))
1724e5dd7070Spatrick CommaVisitor(*this).Visit(Cond);
1725e5dd7070Spatrick
1726e5dd7070Spatrick return new (Context) DoStmt(Body, Cond, DoLoc, WhileLoc, CondRParen);
1727e5dd7070Spatrick }
1728e5dd7070Spatrick
1729e5dd7070Spatrick namespace {
1730e5dd7070Spatrick // Use SetVector since the diagnostic cares about the ordering of the Decl's.
1731e5dd7070Spatrick using DeclSetVector =
1732e5dd7070Spatrick llvm::SetVector<VarDecl *, llvm::SmallVector<VarDecl *, 8>,
1733e5dd7070Spatrick llvm::SmallPtrSet<VarDecl *, 8>>;
1734e5dd7070Spatrick
1735e5dd7070Spatrick // This visitor will traverse a conditional statement and store all
1736e5dd7070Spatrick // the evaluated decls into a vector. Simple is set to true if none
1737e5dd7070Spatrick // of the excluded constructs are used.
1738e5dd7070Spatrick class DeclExtractor : public EvaluatedExprVisitor<DeclExtractor> {
1739e5dd7070Spatrick DeclSetVector &Decls;
1740e5dd7070Spatrick SmallVectorImpl<SourceRange> &Ranges;
1741e5dd7070Spatrick bool Simple;
1742e5dd7070Spatrick public:
1743e5dd7070Spatrick typedef EvaluatedExprVisitor<DeclExtractor> Inherited;
1744e5dd7070Spatrick
DeclExtractor(Sema & S,DeclSetVector & Decls,SmallVectorImpl<SourceRange> & Ranges)1745e5dd7070Spatrick DeclExtractor(Sema &S, DeclSetVector &Decls,
1746e5dd7070Spatrick SmallVectorImpl<SourceRange> &Ranges) :
1747e5dd7070Spatrick Inherited(S.Context),
1748e5dd7070Spatrick Decls(Decls),
1749e5dd7070Spatrick Ranges(Ranges),
1750e5dd7070Spatrick Simple(true) {}
1751e5dd7070Spatrick
isSimple()1752e5dd7070Spatrick bool isSimple() { return Simple; }
1753e5dd7070Spatrick
1754e5dd7070Spatrick // Replaces the method in EvaluatedExprVisitor.
VisitMemberExpr(MemberExpr * E)1755e5dd7070Spatrick void VisitMemberExpr(MemberExpr* E) {
1756e5dd7070Spatrick Simple = false;
1757e5dd7070Spatrick }
1758e5dd7070Spatrick
1759ec727ea7Spatrick // Any Stmt not explicitly listed will cause the condition to be marked
1760ec727ea7Spatrick // complex.
VisitStmt(Stmt * S)1761ec727ea7Spatrick void VisitStmt(Stmt *S) { Simple = false; }
1762e5dd7070Spatrick
VisitBinaryOperator(BinaryOperator * E)1763e5dd7070Spatrick void VisitBinaryOperator(BinaryOperator *E) {
1764e5dd7070Spatrick Visit(E->getLHS());
1765e5dd7070Spatrick Visit(E->getRHS());
1766e5dd7070Spatrick }
1767e5dd7070Spatrick
VisitCastExpr(CastExpr * E)1768e5dd7070Spatrick void VisitCastExpr(CastExpr *E) {
1769e5dd7070Spatrick Visit(E->getSubExpr());
1770e5dd7070Spatrick }
1771e5dd7070Spatrick
VisitUnaryOperator(UnaryOperator * E)1772e5dd7070Spatrick void VisitUnaryOperator(UnaryOperator *E) {
1773e5dd7070Spatrick // Skip checking conditionals with derefernces.
1774e5dd7070Spatrick if (E->getOpcode() == UO_Deref)
1775e5dd7070Spatrick Simple = false;
1776e5dd7070Spatrick else
1777e5dd7070Spatrick Visit(E->getSubExpr());
1778e5dd7070Spatrick }
1779e5dd7070Spatrick
VisitConditionalOperator(ConditionalOperator * E)1780e5dd7070Spatrick void VisitConditionalOperator(ConditionalOperator *E) {
1781e5dd7070Spatrick Visit(E->getCond());
1782e5dd7070Spatrick Visit(E->getTrueExpr());
1783e5dd7070Spatrick Visit(E->getFalseExpr());
1784e5dd7070Spatrick }
1785e5dd7070Spatrick
VisitParenExpr(ParenExpr * E)1786e5dd7070Spatrick void VisitParenExpr(ParenExpr *E) {
1787e5dd7070Spatrick Visit(E->getSubExpr());
1788e5dd7070Spatrick }
1789e5dd7070Spatrick
VisitBinaryConditionalOperator(BinaryConditionalOperator * E)1790e5dd7070Spatrick void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
1791e5dd7070Spatrick Visit(E->getOpaqueValue()->getSourceExpr());
1792e5dd7070Spatrick Visit(E->getFalseExpr());
1793e5dd7070Spatrick }
1794e5dd7070Spatrick
VisitIntegerLiteral(IntegerLiteral * E)1795e5dd7070Spatrick void VisitIntegerLiteral(IntegerLiteral *E) { }
VisitFloatingLiteral(FloatingLiteral * E)1796e5dd7070Spatrick void VisitFloatingLiteral(FloatingLiteral *E) { }
VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr * E)1797e5dd7070Spatrick void VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr *E) { }
VisitCharacterLiteral(CharacterLiteral * E)1798e5dd7070Spatrick void VisitCharacterLiteral(CharacterLiteral *E) { }
VisitGNUNullExpr(GNUNullExpr * E)1799e5dd7070Spatrick void VisitGNUNullExpr(GNUNullExpr *E) { }
VisitImaginaryLiteral(ImaginaryLiteral * E)1800e5dd7070Spatrick void VisitImaginaryLiteral(ImaginaryLiteral *E) { }
1801e5dd7070Spatrick
VisitDeclRefExpr(DeclRefExpr * E)1802e5dd7070Spatrick void VisitDeclRefExpr(DeclRefExpr *E) {
1803e5dd7070Spatrick VarDecl *VD = dyn_cast<VarDecl>(E->getDecl());
1804e5dd7070Spatrick if (!VD) {
1805e5dd7070Spatrick // Don't allow unhandled Decl types.
1806e5dd7070Spatrick Simple = false;
1807e5dd7070Spatrick return;
1808e5dd7070Spatrick }
1809e5dd7070Spatrick
1810e5dd7070Spatrick Ranges.push_back(E->getSourceRange());
1811e5dd7070Spatrick
1812e5dd7070Spatrick Decls.insert(VD);
1813e5dd7070Spatrick }
1814e5dd7070Spatrick
1815e5dd7070Spatrick }; // end class DeclExtractor
1816e5dd7070Spatrick
1817e5dd7070Spatrick // DeclMatcher checks to see if the decls are used in a non-evaluated
1818e5dd7070Spatrick // context.
1819e5dd7070Spatrick class DeclMatcher : public EvaluatedExprVisitor<DeclMatcher> {
1820e5dd7070Spatrick DeclSetVector &Decls;
1821e5dd7070Spatrick bool FoundDecl;
1822e5dd7070Spatrick
1823e5dd7070Spatrick public:
1824e5dd7070Spatrick typedef EvaluatedExprVisitor<DeclMatcher> Inherited;
1825e5dd7070Spatrick
DeclMatcher(Sema & S,DeclSetVector & Decls,Stmt * Statement)1826e5dd7070Spatrick DeclMatcher(Sema &S, DeclSetVector &Decls, Stmt *Statement) :
1827e5dd7070Spatrick Inherited(S.Context), Decls(Decls), FoundDecl(false) {
1828e5dd7070Spatrick if (!Statement) return;
1829e5dd7070Spatrick
1830e5dd7070Spatrick Visit(Statement);
1831e5dd7070Spatrick }
1832e5dd7070Spatrick
VisitReturnStmt(ReturnStmt * S)1833e5dd7070Spatrick void VisitReturnStmt(ReturnStmt *S) {
1834e5dd7070Spatrick FoundDecl = true;
1835e5dd7070Spatrick }
1836e5dd7070Spatrick
VisitBreakStmt(BreakStmt * S)1837e5dd7070Spatrick void VisitBreakStmt(BreakStmt *S) {
1838e5dd7070Spatrick FoundDecl = true;
1839e5dd7070Spatrick }
1840e5dd7070Spatrick
VisitGotoStmt(GotoStmt * S)1841e5dd7070Spatrick void VisitGotoStmt(GotoStmt *S) {
1842e5dd7070Spatrick FoundDecl = true;
1843e5dd7070Spatrick }
1844e5dd7070Spatrick
VisitCastExpr(CastExpr * E)1845e5dd7070Spatrick void VisitCastExpr(CastExpr *E) {
1846e5dd7070Spatrick if (E->getCastKind() == CK_LValueToRValue)
1847e5dd7070Spatrick CheckLValueToRValueCast(E->getSubExpr());
1848e5dd7070Spatrick else
1849e5dd7070Spatrick Visit(E->getSubExpr());
1850e5dd7070Spatrick }
1851e5dd7070Spatrick
CheckLValueToRValueCast(Expr * E)1852e5dd7070Spatrick void CheckLValueToRValueCast(Expr *E) {
1853e5dd7070Spatrick E = E->IgnoreParenImpCasts();
1854e5dd7070Spatrick
1855e5dd7070Spatrick if (isa<DeclRefExpr>(E)) {
1856e5dd7070Spatrick return;
1857e5dd7070Spatrick }
1858e5dd7070Spatrick
1859e5dd7070Spatrick if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
1860e5dd7070Spatrick Visit(CO->getCond());
1861e5dd7070Spatrick CheckLValueToRValueCast(CO->getTrueExpr());
1862e5dd7070Spatrick CheckLValueToRValueCast(CO->getFalseExpr());
1863e5dd7070Spatrick return;
1864e5dd7070Spatrick }
1865e5dd7070Spatrick
1866e5dd7070Spatrick if (BinaryConditionalOperator *BCO =
1867e5dd7070Spatrick dyn_cast<BinaryConditionalOperator>(E)) {
1868e5dd7070Spatrick CheckLValueToRValueCast(BCO->getOpaqueValue()->getSourceExpr());
1869e5dd7070Spatrick CheckLValueToRValueCast(BCO->getFalseExpr());
1870e5dd7070Spatrick return;
1871e5dd7070Spatrick }
1872e5dd7070Spatrick
1873e5dd7070Spatrick Visit(E);
1874e5dd7070Spatrick }
1875e5dd7070Spatrick
VisitDeclRefExpr(DeclRefExpr * E)1876e5dd7070Spatrick void VisitDeclRefExpr(DeclRefExpr *E) {
1877e5dd7070Spatrick if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl()))
1878e5dd7070Spatrick if (Decls.count(VD))
1879e5dd7070Spatrick FoundDecl = true;
1880e5dd7070Spatrick }
1881e5dd7070Spatrick
VisitPseudoObjectExpr(PseudoObjectExpr * POE)1882e5dd7070Spatrick void VisitPseudoObjectExpr(PseudoObjectExpr *POE) {
1883e5dd7070Spatrick // Only need to visit the semantics for POE.
1884e5dd7070Spatrick // SyntaticForm doesn't really use the Decal.
1885e5dd7070Spatrick for (auto *S : POE->semantics()) {
1886e5dd7070Spatrick if (auto *OVE = dyn_cast<OpaqueValueExpr>(S))
1887e5dd7070Spatrick // Look past the OVE into the expression it binds.
1888e5dd7070Spatrick Visit(OVE->getSourceExpr());
1889e5dd7070Spatrick else
1890e5dd7070Spatrick Visit(S);
1891e5dd7070Spatrick }
1892e5dd7070Spatrick }
1893e5dd7070Spatrick
FoundDeclInUse()1894e5dd7070Spatrick bool FoundDeclInUse() { return FoundDecl; }
1895e5dd7070Spatrick
1896e5dd7070Spatrick }; // end class DeclMatcher
1897e5dd7070Spatrick
CheckForLoopConditionalStatement(Sema & S,Expr * Second,Expr * Third,Stmt * Body)1898e5dd7070Spatrick void CheckForLoopConditionalStatement(Sema &S, Expr *Second,
1899e5dd7070Spatrick Expr *Third, Stmt *Body) {
1900e5dd7070Spatrick // Condition is empty
1901e5dd7070Spatrick if (!Second) return;
1902e5dd7070Spatrick
1903e5dd7070Spatrick if (S.Diags.isIgnored(diag::warn_variables_not_in_loop_body,
1904e5dd7070Spatrick Second->getBeginLoc()))
1905e5dd7070Spatrick return;
1906e5dd7070Spatrick
1907e5dd7070Spatrick PartialDiagnostic PDiag = S.PDiag(diag::warn_variables_not_in_loop_body);
1908e5dd7070Spatrick DeclSetVector Decls;
1909e5dd7070Spatrick SmallVector<SourceRange, 10> Ranges;
1910e5dd7070Spatrick DeclExtractor DE(S, Decls, Ranges);
1911e5dd7070Spatrick DE.Visit(Second);
1912e5dd7070Spatrick
1913e5dd7070Spatrick // Don't analyze complex conditionals.
1914e5dd7070Spatrick if (!DE.isSimple()) return;
1915e5dd7070Spatrick
1916e5dd7070Spatrick // No decls found.
1917e5dd7070Spatrick if (Decls.size() == 0) return;
1918e5dd7070Spatrick
1919e5dd7070Spatrick // Don't warn on volatile, static, or global variables.
1920e5dd7070Spatrick for (auto *VD : Decls)
1921e5dd7070Spatrick if (VD->getType().isVolatileQualified() || VD->hasGlobalStorage())
1922e5dd7070Spatrick return;
1923e5dd7070Spatrick
1924e5dd7070Spatrick if (DeclMatcher(S, Decls, Second).FoundDeclInUse() ||
1925e5dd7070Spatrick DeclMatcher(S, Decls, Third).FoundDeclInUse() ||
1926e5dd7070Spatrick DeclMatcher(S, Decls, Body).FoundDeclInUse())
1927e5dd7070Spatrick return;
1928e5dd7070Spatrick
1929e5dd7070Spatrick // Load decl names into diagnostic.
1930e5dd7070Spatrick if (Decls.size() > 4) {
1931e5dd7070Spatrick PDiag << 0;
1932e5dd7070Spatrick } else {
1933e5dd7070Spatrick PDiag << (unsigned)Decls.size();
1934e5dd7070Spatrick for (auto *VD : Decls)
1935e5dd7070Spatrick PDiag << VD->getDeclName();
1936e5dd7070Spatrick }
1937e5dd7070Spatrick
1938e5dd7070Spatrick for (auto Range : Ranges)
1939e5dd7070Spatrick PDiag << Range;
1940e5dd7070Spatrick
1941e5dd7070Spatrick S.Diag(Ranges.begin()->getBegin(), PDiag);
1942e5dd7070Spatrick }
1943e5dd7070Spatrick
1944e5dd7070Spatrick // If Statement is an incemement or decrement, return true and sets the
1945e5dd7070Spatrick // variables Increment and DRE.
ProcessIterationStmt(Sema & S,Stmt * Statement,bool & Increment,DeclRefExpr * & DRE)1946e5dd7070Spatrick bool ProcessIterationStmt(Sema &S, Stmt* Statement, bool &Increment,
1947e5dd7070Spatrick DeclRefExpr *&DRE) {
1948e5dd7070Spatrick if (auto Cleanups = dyn_cast<ExprWithCleanups>(Statement))
1949e5dd7070Spatrick if (!Cleanups->cleanupsHaveSideEffects())
1950e5dd7070Spatrick Statement = Cleanups->getSubExpr();
1951e5dd7070Spatrick
1952e5dd7070Spatrick if (UnaryOperator *UO = dyn_cast<UnaryOperator>(Statement)) {
1953e5dd7070Spatrick switch (UO->getOpcode()) {
1954e5dd7070Spatrick default: return false;
1955e5dd7070Spatrick case UO_PostInc:
1956e5dd7070Spatrick case UO_PreInc:
1957e5dd7070Spatrick Increment = true;
1958e5dd7070Spatrick break;
1959e5dd7070Spatrick case UO_PostDec:
1960e5dd7070Spatrick case UO_PreDec:
1961e5dd7070Spatrick Increment = false;
1962e5dd7070Spatrick break;
1963e5dd7070Spatrick }
1964e5dd7070Spatrick DRE = dyn_cast<DeclRefExpr>(UO->getSubExpr());
1965e5dd7070Spatrick return DRE;
1966e5dd7070Spatrick }
1967e5dd7070Spatrick
1968e5dd7070Spatrick if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(Statement)) {
1969e5dd7070Spatrick FunctionDecl *FD = Call->getDirectCallee();
1970e5dd7070Spatrick if (!FD || !FD->isOverloadedOperator()) return false;
1971e5dd7070Spatrick switch (FD->getOverloadedOperator()) {
1972e5dd7070Spatrick default: return false;
1973e5dd7070Spatrick case OO_PlusPlus:
1974e5dd7070Spatrick Increment = true;
1975e5dd7070Spatrick break;
1976e5dd7070Spatrick case OO_MinusMinus:
1977e5dd7070Spatrick Increment = false;
1978e5dd7070Spatrick break;
1979e5dd7070Spatrick }
1980e5dd7070Spatrick DRE = dyn_cast<DeclRefExpr>(Call->getArg(0));
1981e5dd7070Spatrick return DRE;
1982e5dd7070Spatrick }
1983e5dd7070Spatrick
1984e5dd7070Spatrick return false;
1985e5dd7070Spatrick }
1986e5dd7070Spatrick
1987e5dd7070Spatrick // A visitor to determine if a continue or break statement is a
1988e5dd7070Spatrick // subexpression.
1989e5dd7070Spatrick class BreakContinueFinder : public ConstEvaluatedExprVisitor<BreakContinueFinder> {
1990e5dd7070Spatrick SourceLocation BreakLoc;
1991e5dd7070Spatrick SourceLocation ContinueLoc;
1992e5dd7070Spatrick bool InSwitch = false;
1993e5dd7070Spatrick
1994e5dd7070Spatrick public:
BreakContinueFinder(Sema & S,const Stmt * Body)1995e5dd7070Spatrick BreakContinueFinder(Sema &S, const Stmt* Body) :
1996e5dd7070Spatrick Inherited(S.Context) {
1997e5dd7070Spatrick Visit(Body);
1998e5dd7070Spatrick }
1999e5dd7070Spatrick
2000e5dd7070Spatrick typedef ConstEvaluatedExprVisitor<BreakContinueFinder> Inherited;
2001e5dd7070Spatrick
VisitContinueStmt(const ContinueStmt * E)2002e5dd7070Spatrick void VisitContinueStmt(const ContinueStmt* E) {
2003e5dd7070Spatrick ContinueLoc = E->getContinueLoc();
2004e5dd7070Spatrick }
2005e5dd7070Spatrick
VisitBreakStmt(const BreakStmt * E)2006e5dd7070Spatrick void VisitBreakStmt(const BreakStmt* E) {
2007e5dd7070Spatrick if (!InSwitch)
2008e5dd7070Spatrick BreakLoc = E->getBreakLoc();
2009e5dd7070Spatrick }
2010e5dd7070Spatrick
VisitSwitchStmt(const SwitchStmt * S)2011e5dd7070Spatrick void VisitSwitchStmt(const SwitchStmt* S) {
2012e5dd7070Spatrick if (const Stmt *Init = S->getInit())
2013e5dd7070Spatrick Visit(Init);
2014e5dd7070Spatrick if (const Stmt *CondVar = S->getConditionVariableDeclStmt())
2015e5dd7070Spatrick Visit(CondVar);
2016e5dd7070Spatrick if (const Stmt *Cond = S->getCond())
2017e5dd7070Spatrick Visit(Cond);
2018e5dd7070Spatrick
2019e5dd7070Spatrick // Don't return break statements from the body of a switch.
2020e5dd7070Spatrick InSwitch = true;
2021e5dd7070Spatrick if (const Stmt *Body = S->getBody())
2022e5dd7070Spatrick Visit(Body);
2023e5dd7070Spatrick InSwitch = false;
2024e5dd7070Spatrick }
2025e5dd7070Spatrick
VisitForStmt(const ForStmt * S)2026e5dd7070Spatrick void VisitForStmt(const ForStmt *S) {
2027e5dd7070Spatrick // Only visit the init statement of a for loop; the body
2028e5dd7070Spatrick // has a different break/continue scope.
2029e5dd7070Spatrick if (const Stmt *Init = S->getInit())
2030e5dd7070Spatrick Visit(Init);
2031e5dd7070Spatrick }
2032e5dd7070Spatrick
VisitWhileStmt(const WhileStmt *)2033e5dd7070Spatrick void VisitWhileStmt(const WhileStmt *) {
2034e5dd7070Spatrick // Do nothing; the children of a while loop have a different
2035e5dd7070Spatrick // break/continue scope.
2036e5dd7070Spatrick }
2037e5dd7070Spatrick
VisitDoStmt(const DoStmt *)2038e5dd7070Spatrick void VisitDoStmt(const DoStmt *) {
2039e5dd7070Spatrick // Do nothing; the children of a while loop have a different
2040e5dd7070Spatrick // break/continue scope.
2041e5dd7070Spatrick }
2042e5dd7070Spatrick
VisitCXXForRangeStmt(const CXXForRangeStmt * S)2043e5dd7070Spatrick void VisitCXXForRangeStmt(const CXXForRangeStmt *S) {
2044e5dd7070Spatrick // Only visit the initialization of a for loop; the body
2045e5dd7070Spatrick // has a different break/continue scope.
2046e5dd7070Spatrick if (const Stmt *Init = S->getInit())
2047e5dd7070Spatrick Visit(Init);
2048e5dd7070Spatrick if (const Stmt *Range = S->getRangeStmt())
2049e5dd7070Spatrick Visit(Range);
2050e5dd7070Spatrick if (const Stmt *Begin = S->getBeginStmt())
2051e5dd7070Spatrick Visit(Begin);
2052e5dd7070Spatrick if (const Stmt *End = S->getEndStmt())
2053e5dd7070Spatrick Visit(End);
2054e5dd7070Spatrick }
2055e5dd7070Spatrick
VisitObjCForCollectionStmt(const ObjCForCollectionStmt * S)2056e5dd7070Spatrick void VisitObjCForCollectionStmt(const ObjCForCollectionStmt *S) {
2057e5dd7070Spatrick // Only visit the initialization of a for loop; the body
2058e5dd7070Spatrick // has a different break/continue scope.
2059e5dd7070Spatrick if (const Stmt *Element = S->getElement())
2060e5dd7070Spatrick Visit(Element);
2061e5dd7070Spatrick if (const Stmt *Collection = S->getCollection())
2062e5dd7070Spatrick Visit(Collection);
2063e5dd7070Spatrick }
2064e5dd7070Spatrick
ContinueFound()2065e5dd7070Spatrick bool ContinueFound() { return ContinueLoc.isValid(); }
BreakFound()2066e5dd7070Spatrick bool BreakFound() { return BreakLoc.isValid(); }
GetContinueLoc()2067e5dd7070Spatrick SourceLocation GetContinueLoc() { return ContinueLoc; }
GetBreakLoc()2068e5dd7070Spatrick SourceLocation GetBreakLoc() { return BreakLoc; }
2069e5dd7070Spatrick
2070e5dd7070Spatrick }; // end class BreakContinueFinder
2071e5dd7070Spatrick
2072e5dd7070Spatrick // Emit a warning when a loop increment/decrement appears twice per loop
2073e5dd7070Spatrick // iteration. The conditions which trigger this warning are:
2074e5dd7070Spatrick // 1) The last statement in the loop body and the third expression in the
2075e5dd7070Spatrick // for loop are both increment or both decrement of the same variable
2076e5dd7070Spatrick // 2) No continue statements in the loop body.
CheckForRedundantIteration(Sema & S,Expr * Third,Stmt * Body)2077e5dd7070Spatrick void CheckForRedundantIteration(Sema &S, Expr *Third, Stmt *Body) {
2078e5dd7070Spatrick // Return when there is nothing to check.
2079e5dd7070Spatrick if (!Body || !Third) return;
2080e5dd7070Spatrick
2081e5dd7070Spatrick if (S.Diags.isIgnored(diag::warn_redundant_loop_iteration,
2082e5dd7070Spatrick Third->getBeginLoc()))
2083e5dd7070Spatrick return;
2084e5dd7070Spatrick
2085e5dd7070Spatrick // Get the last statement from the loop body.
2086e5dd7070Spatrick CompoundStmt *CS = dyn_cast<CompoundStmt>(Body);
2087e5dd7070Spatrick if (!CS || CS->body_empty()) return;
2088e5dd7070Spatrick Stmt *LastStmt = CS->body_back();
2089e5dd7070Spatrick if (!LastStmt) return;
2090e5dd7070Spatrick
2091e5dd7070Spatrick bool LoopIncrement, LastIncrement;
2092e5dd7070Spatrick DeclRefExpr *LoopDRE, *LastDRE;
2093e5dd7070Spatrick
2094e5dd7070Spatrick if (!ProcessIterationStmt(S, Third, LoopIncrement, LoopDRE)) return;
2095e5dd7070Spatrick if (!ProcessIterationStmt(S, LastStmt, LastIncrement, LastDRE)) return;
2096e5dd7070Spatrick
2097e5dd7070Spatrick // Check that the two statements are both increments or both decrements
2098e5dd7070Spatrick // on the same variable.
2099e5dd7070Spatrick if (LoopIncrement != LastIncrement ||
2100e5dd7070Spatrick LoopDRE->getDecl() != LastDRE->getDecl()) return;
2101e5dd7070Spatrick
2102e5dd7070Spatrick if (BreakContinueFinder(S, Body).ContinueFound()) return;
2103e5dd7070Spatrick
2104e5dd7070Spatrick S.Diag(LastDRE->getLocation(), diag::warn_redundant_loop_iteration)
2105e5dd7070Spatrick << LastDRE->getDecl() << LastIncrement;
2106e5dd7070Spatrick S.Diag(LoopDRE->getLocation(), diag::note_loop_iteration_here)
2107e5dd7070Spatrick << LoopIncrement;
2108e5dd7070Spatrick }
2109e5dd7070Spatrick
2110e5dd7070Spatrick } // end namespace
2111e5dd7070Spatrick
2112e5dd7070Spatrick
CheckBreakContinueBinding(Expr * E)2113e5dd7070Spatrick void Sema::CheckBreakContinueBinding(Expr *E) {
2114e5dd7070Spatrick if (!E || getLangOpts().CPlusPlus)
2115e5dd7070Spatrick return;
2116e5dd7070Spatrick BreakContinueFinder BCFinder(*this, E);
2117e5dd7070Spatrick Scope *BreakParent = CurScope->getBreakParent();
2118e5dd7070Spatrick if (BCFinder.BreakFound() && BreakParent) {
2119e5dd7070Spatrick if (BreakParent->getFlags() & Scope::SwitchScope) {
2120e5dd7070Spatrick Diag(BCFinder.GetBreakLoc(), diag::warn_break_binds_to_switch);
2121e5dd7070Spatrick } else {
2122e5dd7070Spatrick Diag(BCFinder.GetBreakLoc(), diag::warn_loop_ctrl_binds_to_inner)
2123e5dd7070Spatrick << "break";
2124e5dd7070Spatrick }
2125e5dd7070Spatrick } else if (BCFinder.ContinueFound() && CurScope->getContinueParent()) {
2126e5dd7070Spatrick Diag(BCFinder.GetContinueLoc(), diag::warn_loop_ctrl_binds_to_inner)
2127e5dd7070Spatrick << "continue";
2128e5dd7070Spatrick }
2129e5dd7070Spatrick }
2130e5dd7070Spatrick
ActOnForStmt(SourceLocation ForLoc,SourceLocation LParenLoc,Stmt * First,ConditionResult Second,FullExprArg third,SourceLocation RParenLoc,Stmt * Body)2131e5dd7070Spatrick StmtResult Sema::ActOnForStmt(SourceLocation ForLoc, SourceLocation LParenLoc,
2132e5dd7070Spatrick Stmt *First, ConditionResult Second,
2133e5dd7070Spatrick FullExprArg third, SourceLocation RParenLoc,
2134e5dd7070Spatrick Stmt *Body) {
2135e5dd7070Spatrick if (Second.isInvalid())
2136e5dd7070Spatrick return StmtError();
2137e5dd7070Spatrick
2138e5dd7070Spatrick if (!getLangOpts().CPlusPlus) {
2139e5dd7070Spatrick if (DeclStmt *DS = dyn_cast_or_null<DeclStmt>(First)) {
2140e5dd7070Spatrick // C99 6.8.5p3: The declaration part of a 'for' statement shall only
2141e5dd7070Spatrick // declare identifiers for objects having storage class 'auto' or
2142e5dd7070Spatrick // 'register'.
2143a9ac8606Spatrick const Decl *NonVarSeen = nullptr;
2144a9ac8606Spatrick bool VarDeclSeen = false;
2145e5dd7070Spatrick for (auto *DI : DS->decls()) {
2146a9ac8606Spatrick if (VarDecl *VD = dyn_cast<VarDecl>(DI)) {
2147a9ac8606Spatrick VarDeclSeen = true;
2148a9ac8606Spatrick if (VD->isLocalVarDecl() && !VD->hasLocalStorage()) {
2149e5dd7070Spatrick Diag(DI->getLocation(), diag::err_non_local_variable_decl_in_for);
2150e5dd7070Spatrick DI->setInvalidDecl();
2151e5dd7070Spatrick }
2152a9ac8606Spatrick } else if (!NonVarSeen) {
2153a9ac8606Spatrick // Keep track of the first non-variable declaration we saw so that
2154a9ac8606Spatrick // we can diagnose if we don't see any variable declarations. This
2155a9ac8606Spatrick // covers a case like declaring a typedef, function, or structure
2156a9ac8606Spatrick // type rather than a variable.
2157a9ac8606Spatrick NonVarSeen = DI;
2158e5dd7070Spatrick }
2159e5dd7070Spatrick }
2160a9ac8606Spatrick // Diagnose if we saw a non-variable declaration but no variable
2161a9ac8606Spatrick // declarations.
2162a9ac8606Spatrick if (NonVarSeen && !VarDeclSeen)
2163a9ac8606Spatrick Diag(NonVarSeen->getLocation(), diag::err_non_variable_decl_in_for);
2164a9ac8606Spatrick }
2165e5dd7070Spatrick }
2166e5dd7070Spatrick
2167e5dd7070Spatrick CheckBreakContinueBinding(Second.get().second);
2168e5dd7070Spatrick CheckBreakContinueBinding(third.get());
2169e5dd7070Spatrick
2170e5dd7070Spatrick if (!Second.get().first)
2171e5dd7070Spatrick CheckForLoopConditionalStatement(*this, Second.get().second, third.get(),
2172e5dd7070Spatrick Body);
2173e5dd7070Spatrick CheckForRedundantIteration(*this, third.get(), Body);
2174e5dd7070Spatrick
2175e5dd7070Spatrick if (Second.get().second &&
2176e5dd7070Spatrick !Diags.isIgnored(diag::warn_comma_operator,
2177e5dd7070Spatrick Second.get().second->getExprLoc()))
2178e5dd7070Spatrick CommaVisitor(*this).Visit(Second.get().second);
2179e5dd7070Spatrick
2180e5dd7070Spatrick Expr *Third = third.release().getAs<Expr>();
2181e5dd7070Spatrick if (isa<NullStmt>(Body))
2182e5dd7070Spatrick getCurCompoundScope().setHasEmptyLoopBodies();
2183e5dd7070Spatrick
2184e5dd7070Spatrick return new (Context)
2185e5dd7070Spatrick ForStmt(Context, First, Second.get().second, Second.get().first, Third,
2186e5dd7070Spatrick Body, ForLoc, LParenLoc, RParenLoc);
2187e5dd7070Spatrick }
2188e5dd7070Spatrick
2189e5dd7070Spatrick /// In an Objective C collection iteration statement:
2190e5dd7070Spatrick /// for (x in y)
2191e5dd7070Spatrick /// x can be an arbitrary l-value expression. Bind it up as a
2192e5dd7070Spatrick /// full-expression.
ActOnForEachLValueExpr(Expr * E)2193e5dd7070Spatrick StmtResult Sema::ActOnForEachLValueExpr(Expr *E) {
2194e5dd7070Spatrick // Reduce placeholder expressions here. Note that this rejects the
2195e5dd7070Spatrick // use of pseudo-object l-values in this position.
2196e5dd7070Spatrick ExprResult result = CheckPlaceholderExpr(E);
2197e5dd7070Spatrick if (result.isInvalid()) return StmtError();
2198e5dd7070Spatrick E = result.get();
2199e5dd7070Spatrick
2200e5dd7070Spatrick ExprResult FullExpr = ActOnFinishFullExpr(E, /*DiscardedValue*/ false);
2201e5dd7070Spatrick if (FullExpr.isInvalid())
2202e5dd7070Spatrick return StmtError();
2203e5dd7070Spatrick return StmtResult(static_cast<Stmt*>(FullExpr.get()));
2204e5dd7070Spatrick }
2205e5dd7070Spatrick
2206e5dd7070Spatrick ExprResult
CheckObjCForCollectionOperand(SourceLocation forLoc,Expr * collection)2207e5dd7070Spatrick Sema::CheckObjCForCollectionOperand(SourceLocation forLoc, Expr *collection) {
2208e5dd7070Spatrick if (!collection)
2209e5dd7070Spatrick return ExprError();
2210e5dd7070Spatrick
2211e5dd7070Spatrick ExprResult result = CorrectDelayedTyposInExpr(collection);
2212e5dd7070Spatrick if (!result.isUsable())
2213e5dd7070Spatrick return ExprError();
2214e5dd7070Spatrick collection = result.get();
2215e5dd7070Spatrick
2216e5dd7070Spatrick // Bail out early if we've got a type-dependent expression.
2217e5dd7070Spatrick if (collection->isTypeDependent()) return collection;
2218e5dd7070Spatrick
2219e5dd7070Spatrick // Perform normal l-value conversion.
2220e5dd7070Spatrick result = DefaultFunctionArrayLvalueConversion(collection);
2221e5dd7070Spatrick if (result.isInvalid())
2222e5dd7070Spatrick return ExprError();
2223e5dd7070Spatrick collection = result.get();
2224e5dd7070Spatrick
2225e5dd7070Spatrick // The operand needs to have object-pointer type.
2226e5dd7070Spatrick // TODO: should we do a contextual conversion?
2227e5dd7070Spatrick const ObjCObjectPointerType *pointerType =
2228e5dd7070Spatrick collection->getType()->getAs<ObjCObjectPointerType>();
2229e5dd7070Spatrick if (!pointerType)
2230e5dd7070Spatrick return Diag(forLoc, diag::err_collection_expr_type)
2231e5dd7070Spatrick << collection->getType() << collection->getSourceRange();
2232e5dd7070Spatrick
2233e5dd7070Spatrick // Check that the operand provides
2234e5dd7070Spatrick // - countByEnumeratingWithState:objects:count:
2235e5dd7070Spatrick const ObjCObjectType *objectType = pointerType->getObjectType();
2236e5dd7070Spatrick ObjCInterfaceDecl *iface = objectType->getInterface();
2237e5dd7070Spatrick
2238e5dd7070Spatrick // If we have a forward-declared type, we can't do this check.
2239e5dd7070Spatrick // Under ARC, it is an error not to have a forward-declared class.
2240e5dd7070Spatrick if (iface &&
2241e5dd7070Spatrick (getLangOpts().ObjCAutoRefCount
2242e5dd7070Spatrick ? RequireCompleteType(forLoc, QualType(objectType, 0),
2243e5dd7070Spatrick diag::err_arc_collection_forward, collection)
2244e5dd7070Spatrick : !isCompleteType(forLoc, QualType(objectType, 0)))) {
2245e5dd7070Spatrick // Otherwise, if we have any useful type information, check that
2246e5dd7070Spatrick // the type declares the appropriate method.
2247e5dd7070Spatrick } else if (iface || !objectType->qual_empty()) {
2248e5dd7070Spatrick IdentifierInfo *selectorIdents[] = {
2249e5dd7070Spatrick &Context.Idents.get("countByEnumeratingWithState"),
2250e5dd7070Spatrick &Context.Idents.get("objects"),
2251e5dd7070Spatrick &Context.Idents.get("count")
2252e5dd7070Spatrick };
2253e5dd7070Spatrick Selector selector = Context.Selectors.getSelector(3, &selectorIdents[0]);
2254e5dd7070Spatrick
2255e5dd7070Spatrick ObjCMethodDecl *method = nullptr;
2256e5dd7070Spatrick
2257e5dd7070Spatrick // If there's an interface, look in both the public and private APIs.
2258e5dd7070Spatrick if (iface) {
2259e5dd7070Spatrick method = iface->lookupInstanceMethod(selector);
2260e5dd7070Spatrick if (!method) method = iface->lookupPrivateMethod(selector);
2261e5dd7070Spatrick }
2262e5dd7070Spatrick
2263e5dd7070Spatrick // Also check protocol qualifiers.
2264e5dd7070Spatrick if (!method)
2265e5dd7070Spatrick method = LookupMethodInQualifiedType(selector, pointerType,
2266e5dd7070Spatrick /*instance*/ true);
2267e5dd7070Spatrick
2268e5dd7070Spatrick // If we didn't find it anywhere, give up.
2269e5dd7070Spatrick if (!method) {
2270e5dd7070Spatrick Diag(forLoc, diag::warn_collection_expr_type)
2271e5dd7070Spatrick << collection->getType() << selector << collection->getSourceRange();
2272e5dd7070Spatrick }
2273e5dd7070Spatrick
2274e5dd7070Spatrick // TODO: check for an incompatible signature?
2275e5dd7070Spatrick }
2276e5dd7070Spatrick
2277e5dd7070Spatrick // Wrap up any cleanups in the expression.
2278e5dd7070Spatrick return collection;
2279e5dd7070Spatrick }
2280e5dd7070Spatrick
2281e5dd7070Spatrick StmtResult
ActOnObjCForCollectionStmt(SourceLocation ForLoc,Stmt * First,Expr * collection,SourceLocation RParenLoc)2282e5dd7070Spatrick Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc,
2283e5dd7070Spatrick Stmt *First, Expr *collection,
2284e5dd7070Spatrick SourceLocation RParenLoc) {
2285e5dd7070Spatrick setFunctionHasBranchProtectedScope();
2286e5dd7070Spatrick
2287e5dd7070Spatrick ExprResult CollectionExprResult =
2288e5dd7070Spatrick CheckObjCForCollectionOperand(ForLoc, collection);
2289e5dd7070Spatrick
2290e5dd7070Spatrick if (First) {
2291e5dd7070Spatrick QualType FirstType;
2292e5dd7070Spatrick if (DeclStmt *DS = dyn_cast<DeclStmt>(First)) {
2293e5dd7070Spatrick if (!DS->isSingleDecl())
2294e5dd7070Spatrick return StmtError(Diag((*DS->decl_begin())->getLocation(),
2295e5dd7070Spatrick diag::err_toomany_element_decls));
2296e5dd7070Spatrick
2297e5dd7070Spatrick VarDecl *D = dyn_cast<VarDecl>(DS->getSingleDecl());
2298e5dd7070Spatrick if (!D || D->isInvalidDecl())
2299e5dd7070Spatrick return StmtError();
2300e5dd7070Spatrick
2301e5dd7070Spatrick FirstType = D->getType();
2302e5dd7070Spatrick // C99 6.8.5p3: The declaration part of a 'for' statement shall only
2303e5dd7070Spatrick // declare identifiers for objects having storage class 'auto' or
2304e5dd7070Spatrick // 'register'.
2305e5dd7070Spatrick if (!D->hasLocalStorage())
2306e5dd7070Spatrick return StmtError(Diag(D->getLocation(),
2307e5dd7070Spatrick diag::err_non_local_variable_decl_in_for));
2308e5dd7070Spatrick
2309e5dd7070Spatrick // If the type contained 'auto', deduce the 'auto' to 'id'.
2310e5dd7070Spatrick if (FirstType->getContainedAutoType()) {
2311*12c85518Srobert SourceLocation Loc = D->getLocation();
2312*12c85518Srobert OpaqueValueExpr OpaqueId(Loc, Context.getObjCIdType(), VK_PRValue);
2313e5dd7070Spatrick Expr *DeducedInit = &OpaqueId;
2314*12c85518Srobert TemplateDeductionInfo Info(Loc);
2315*12c85518Srobert FirstType = QualType();
2316*12c85518Srobert TemplateDeductionResult Result = DeduceAutoType(
2317*12c85518Srobert D->getTypeSourceInfo()->getTypeLoc(), DeducedInit, FirstType, Info);
2318*12c85518Srobert if (Result != TDK_Success && Result != TDK_AlreadyDiagnosed)
2319e5dd7070Spatrick DiagnoseAutoDeductionFailure(D, DeducedInit);
2320e5dd7070Spatrick if (FirstType.isNull()) {
2321e5dd7070Spatrick D->setInvalidDecl();
2322e5dd7070Spatrick return StmtError();
2323e5dd7070Spatrick }
2324e5dd7070Spatrick
2325e5dd7070Spatrick D->setType(FirstType);
2326e5dd7070Spatrick
2327e5dd7070Spatrick if (!inTemplateInstantiation()) {
2328e5dd7070Spatrick SourceLocation Loc =
2329e5dd7070Spatrick D->getTypeSourceInfo()->getTypeLoc().getBeginLoc();
2330e5dd7070Spatrick Diag(Loc, diag::warn_auto_var_is_id)
2331e5dd7070Spatrick << D->getDeclName();
2332e5dd7070Spatrick }
2333e5dd7070Spatrick }
2334e5dd7070Spatrick
2335e5dd7070Spatrick } else {
2336e5dd7070Spatrick Expr *FirstE = cast<Expr>(First);
2337e5dd7070Spatrick if (!FirstE->isTypeDependent() && !FirstE->isLValue())
2338e5dd7070Spatrick return StmtError(
2339e5dd7070Spatrick Diag(First->getBeginLoc(), diag::err_selector_element_not_lvalue)
2340e5dd7070Spatrick << First->getSourceRange());
2341e5dd7070Spatrick
2342e5dd7070Spatrick FirstType = static_cast<Expr*>(First)->getType();
2343e5dd7070Spatrick if (FirstType.isConstQualified())
2344e5dd7070Spatrick Diag(ForLoc, diag::err_selector_element_const_type)
2345e5dd7070Spatrick << FirstType << First->getSourceRange();
2346e5dd7070Spatrick }
2347e5dd7070Spatrick if (!FirstType->isDependentType() &&
2348e5dd7070Spatrick !FirstType->isObjCObjectPointerType() &&
2349e5dd7070Spatrick !FirstType->isBlockPointerType())
2350e5dd7070Spatrick return StmtError(Diag(ForLoc, diag::err_selector_element_type)
2351e5dd7070Spatrick << FirstType << First->getSourceRange());
2352e5dd7070Spatrick }
2353e5dd7070Spatrick
2354e5dd7070Spatrick if (CollectionExprResult.isInvalid())
2355e5dd7070Spatrick return StmtError();
2356e5dd7070Spatrick
2357e5dd7070Spatrick CollectionExprResult =
2358e5dd7070Spatrick ActOnFinishFullExpr(CollectionExprResult.get(), /*DiscardedValue*/ false);
2359e5dd7070Spatrick if (CollectionExprResult.isInvalid())
2360e5dd7070Spatrick return StmtError();
2361e5dd7070Spatrick
2362e5dd7070Spatrick return new (Context) ObjCForCollectionStmt(First, CollectionExprResult.get(),
2363e5dd7070Spatrick nullptr, ForLoc, RParenLoc);
2364e5dd7070Spatrick }
2365e5dd7070Spatrick
2366e5dd7070Spatrick /// Finish building a variable declaration for a for-range statement.
2367e5dd7070Spatrick /// \return true if an error occurs.
FinishForRangeVarDecl(Sema & SemaRef,VarDecl * Decl,Expr * Init,SourceLocation Loc,int DiagID)2368e5dd7070Spatrick static bool FinishForRangeVarDecl(Sema &SemaRef, VarDecl *Decl, Expr *Init,
2369e5dd7070Spatrick SourceLocation Loc, int DiagID) {
2370e5dd7070Spatrick if (Decl->getType()->isUndeducedType()) {
2371e5dd7070Spatrick ExprResult Res = SemaRef.CorrectDelayedTyposInExpr(Init);
2372e5dd7070Spatrick if (!Res.isUsable()) {
2373e5dd7070Spatrick Decl->setInvalidDecl();
2374e5dd7070Spatrick return true;
2375e5dd7070Spatrick }
2376e5dd7070Spatrick Init = Res.get();
2377e5dd7070Spatrick }
2378e5dd7070Spatrick
2379e5dd7070Spatrick // Deduce the type for the iterator variable now rather than leaving it to
2380e5dd7070Spatrick // AddInitializerToDecl, so we can produce a more suitable diagnostic.
2381e5dd7070Spatrick QualType InitType;
2382*12c85518Srobert if (!isa<InitListExpr>(Init) && Init->getType()->isVoidType()) {
2383e5dd7070Spatrick SemaRef.Diag(Loc, DiagID) << Init->getType();
2384*12c85518Srobert } else {
2385*12c85518Srobert TemplateDeductionInfo Info(Init->getExprLoc());
2386*12c85518Srobert Sema::TemplateDeductionResult Result = SemaRef.DeduceAutoType(
2387*12c85518Srobert Decl->getTypeSourceInfo()->getTypeLoc(), Init, InitType, Info);
2388*12c85518Srobert if (Result != Sema::TDK_Success && Result != Sema::TDK_AlreadyDiagnosed)
2389*12c85518Srobert SemaRef.Diag(Loc, DiagID) << Init->getType();
2390*12c85518Srobert }
2391*12c85518Srobert
2392e5dd7070Spatrick if (InitType.isNull()) {
2393e5dd7070Spatrick Decl->setInvalidDecl();
2394e5dd7070Spatrick return true;
2395e5dd7070Spatrick }
2396e5dd7070Spatrick Decl->setType(InitType);
2397e5dd7070Spatrick
2398e5dd7070Spatrick // In ARC, infer lifetime.
2399e5dd7070Spatrick // FIXME: ARC may want to turn this into 'const __unsafe_unretained' if
2400e5dd7070Spatrick // we're doing the equivalent of fast iteration.
2401e5dd7070Spatrick if (SemaRef.getLangOpts().ObjCAutoRefCount &&
2402e5dd7070Spatrick SemaRef.inferObjCARCLifetime(Decl))
2403e5dd7070Spatrick Decl->setInvalidDecl();
2404e5dd7070Spatrick
2405e5dd7070Spatrick SemaRef.AddInitializerToDecl(Decl, Init, /*DirectInit=*/false);
2406e5dd7070Spatrick SemaRef.FinalizeDeclaration(Decl);
2407e5dd7070Spatrick SemaRef.CurContext->addHiddenDecl(Decl);
2408e5dd7070Spatrick return false;
2409e5dd7070Spatrick }
2410e5dd7070Spatrick
2411e5dd7070Spatrick namespace {
2412e5dd7070Spatrick // An enum to represent whether something is dealing with a call to begin()
2413e5dd7070Spatrick // or a call to end() in a range-based for loop.
2414e5dd7070Spatrick enum BeginEndFunction {
2415e5dd7070Spatrick BEF_begin,
2416e5dd7070Spatrick BEF_end
2417e5dd7070Spatrick };
2418e5dd7070Spatrick
2419e5dd7070Spatrick /// Produce a note indicating which begin/end function was implicitly called
2420e5dd7070Spatrick /// by a C++11 for-range statement. This is often not obvious from the code,
2421e5dd7070Spatrick /// nor from the diagnostics produced when analysing the implicit expressions
2422e5dd7070Spatrick /// required in a for-range statement.
NoteForRangeBeginEndFunction(Sema & SemaRef,Expr * E,BeginEndFunction BEF)2423e5dd7070Spatrick void NoteForRangeBeginEndFunction(Sema &SemaRef, Expr *E,
2424e5dd7070Spatrick BeginEndFunction BEF) {
2425e5dd7070Spatrick CallExpr *CE = dyn_cast<CallExpr>(E);
2426e5dd7070Spatrick if (!CE)
2427e5dd7070Spatrick return;
2428e5dd7070Spatrick FunctionDecl *D = dyn_cast<FunctionDecl>(CE->getCalleeDecl());
2429e5dd7070Spatrick if (!D)
2430e5dd7070Spatrick return;
2431e5dd7070Spatrick SourceLocation Loc = D->getLocation();
2432e5dd7070Spatrick
2433e5dd7070Spatrick std::string Description;
2434e5dd7070Spatrick bool IsTemplate = false;
2435e5dd7070Spatrick if (FunctionTemplateDecl *FunTmpl = D->getPrimaryTemplate()) {
2436e5dd7070Spatrick Description = SemaRef.getTemplateArgumentBindingsText(
2437e5dd7070Spatrick FunTmpl->getTemplateParameters(), *D->getTemplateSpecializationArgs());
2438e5dd7070Spatrick IsTemplate = true;
2439e5dd7070Spatrick }
2440e5dd7070Spatrick
2441e5dd7070Spatrick SemaRef.Diag(Loc, diag::note_for_range_begin_end)
2442e5dd7070Spatrick << BEF << IsTemplate << Description << E->getType();
2443e5dd7070Spatrick }
2444e5dd7070Spatrick
2445e5dd7070Spatrick /// Build a variable declaration for a for-range statement.
BuildForRangeVarDecl(Sema & SemaRef,SourceLocation Loc,QualType Type,StringRef Name)2446e5dd7070Spatrick VarDecl *BuildForRangeVarDecl(Sema &SemaRef, SourceLocation Loc,
2447e5dd7070Spatrick QualType Type, StringRef Name) {
2448e5dd7070Spatrick DeclContext *DC = SemaRef.CurContext;
2449e5dd7070Spatrick IdentifierInfo *II = &SemaRef.PP.getIdentifierTable().get(Name);
2450e5dd7070Spatrick TypeSourceInfo *TInfo = SemaRef.Context.getTrivialTypeSourceInfo(Type, Loc);
2451e5dd7070Spatrick VarDecl *Decl = VarDecl::Create(SemaRef.Context, DC, Loc, Loc, II, Type,
2452e5dd7070Spatrick TInfo, SC_None);
2453e5dd7070Spatrick Decl->setImplicit();
2454e5dd7070Spatrick return Decl;
2455e5dd7070Spatrick }
2456e5dd7070Spatrick
2457e5dd7070Spatrick }
2458e5dd7070Spatrick
ObjCEnumerationCollection(Expr * Collection)2459e5dd7070Spatrick static bool ObjCEnumerationCollection(Expr *Collection) {
2460e5dd7070Spatrick return !Collection->isTypeDependent()
2461e5dd7070Spatrick && Collection->getType()->getAs<ObjCObjectPointerType>() != nullptr;
2462e5dd7070Spatrick }
2463e5dd7070Spatrick
2464e5dd7070Spatrick /// ActOnCXXForRangeStmt - Check and build a C++11 for-range statement.
2465e5dd7070Spatrick ///
2466e5dd7070Spatrick /// C++11 [stmt.ranged]:
2467e5dd7070Spatrick /// A range-based for statement is equivalent to
2468e5dd7070Spatrick ///
2469e5dd7070Spatrick /// {
2470e5dd7070Spatrick /// auto && __range = range-init;
2471e5dd7070Spatrick /// for ( auto __begin = begin-expr,
2472e5dd7070Spatrick /// __end = end-expr;
2473e5dd7070Spatrick /// __begin != __end;
2474e5dd7070Spatrick /// ++__begin ) {
2475e5dd7070Spatrick /// for-range-declaration = *__begin;
2476e5dd7070Spatrick /// statement
2477e5dd7070Spatrick /// }
2478e5dd7070Spatrick /// }
2479e5dd7070Spatrick ///
2480e5dd7070Spatrick /// The body of the loop is not available yet, since it cannot be analysed until
2481e5dd7070Spatrick /// we have determined the type of the for-range-declaration.
ActOnCXXForRangeStmt(Scope * S,SourceLocation ForLoc,SourceLocation CoawaitLoc,Stmt * InitStmt,Stmt * First,SourceLocation ColonLoc,Expr * Range,SourceLocation RParenLoc,BuildForRangeKind Kind)2482e5dd7070Spatrick StmtResult Sema::ActOnCXXForRangeStmt(Scope *S, SourceLocation ForLoc,
2483e5dd7070Spatrick SourceLocation CoawaitLoc, Stmt *InitStmt,
2484e5dd7070Spatrick Stmt *First, SourceLocation ColonLoc,
2485e5dd7070Spatrick Expr *Range, SourceLocation RParenLoc,
2486e5dd7070Spatrick BuildForRangeKind Kind) {
2487*12c85518Srobert // FIXME: recover in order to allow the body to be parsed.
2488e5dd7070Spatrick if (!First)
2489e5dd7070Spatrick return StmtError();
2490e5dd7070Spatrick
2491e5dd7070Spatrick if (Range && ObjCEnumerationCollection(Range)) {
2492e5dd7070Spatrick // FIXME: Support init-statements in Objective-C++20 ranged for statement.
2493e5dd7070Spatrick if (InitStmt)
2494e5dd7070Spatrick return Diag(InitStmt->getBeginLoc(), diag::err_objc_for_range_init_stmt)
2495e5dd7070Spatrick << InitStmt->getSourceRange();
2496e5dd7070Spatrick return ActOnObjCForCollectionStmt(ForLoc, First, Range, RParenLoc);
2497e5dd7070Spatrick }
2498e5dd7070Spatrick
2499e5dd7070Spatrick DeclStmt *DS = dyn_cast<DeclStmt>(First);
2500e5dd7070Spatrick assert(DS && "first part of for range not a decl stmt");
2501e5dd7070Spatrick
2502e5dd7070Spatrick if (!DS->isSingleDecl()) {
2503e5dd7070Spatrick Diag(DS->getBeginLoc(), diag::err_type_defined_in_for_range);
2504e5dd7070Spatrick return StmtError();
2505e5dd7070Spatrick }
2506e5dd7070Spatrick
2507ec727ea7Spatrick // This function is responsible for attaching an initializer to LoopVar. We
2508ec727ea7Spatrick // must call ActOnInitializerError if we fail to do so.
2509e5dd7070Spatrick Decl *LoopVar = DS->getSingleDecl();
2510e5dd7070Spatrick if (LoopVar->isInvalidDecl() || !Range ||
2511e5dd7070Spatrick DiagnoseUnexpandedParameterPack(Range, UPPC_Expression)) {
2512ec727ea7Spatrick ActOnInitializerError(LoopVar);
2513e5dd7070Spatrick return StmtError();
2514e5dd7070Spatrick }
2515e5dd7070Spatrick
2516e5dd7070Spatrick // Build the coroutine state immediately and not later during template
2517e5dd7070Spatrick // instantiation
2518e5dd7070Spatrick if (!CoawaitLoc.isInvalid()) {
2519ec727ea7Spatrick if (!ActOnCoroutineBodyStart(S, CoawaitLoc, "co_await")) {
2520ec727ea7Spatrick ActOnInitializerError(LoopVar);
2521e5dd7070Spatrick return StmtError();
2522e5dd7070Spatrick }
2523ec727ea7Spatrick }
2524e5dd7070Spatrick
2525e5dd7070Spatrick // Build auto && __range = range-init
2526e5dd7070Spatrick // Divide by 2, since the variables are in the inner scope (loop body).
2527e5dd7070Spatrick const auto DepthStr = std::to_string(S->getDepth() / 2);
2528e5dd7070Spatrick SourceLocation RangeLoc = Range->getBeginLoc();
2529e5dd7070Spatrick VarDecl *RangeVar = BuildForRangeVarDecl(*this, RangeLoc,
2530e5dd7070Spatrick Context.getAutoRRefDeductType(),
2531e5dd7070Spatrick std::string("__range") + DepthStr);
2532e5dd7070Spatrick if (FinishForRangeVarDecl(*this, RangeVar, Range, RangeLoc,
2533e5dd7070Spatrick diag::err_for_range_deduction_failure)) {
2534ec727ea7Spatrick ActOnInitializerError(LoopVar);
2535e5dd7070Spatrick return StmtError();
2536e5dd7070Spatrick }
2537e5dd7070Spatrick
2538e5dd7070Spatrick // Claim the type doesn't contain auto: we've already done the checking.
2539e5dd7070Spatrick DeclGroupPtrTy RangeGroup =
2540e5dd7070Spatrick BuildDeclaratorGroup(MutableArrayRef<Decl *>((Decl **)&RangeVar, 1));
2541e5dd7070Spatrick StmtResult RangeDecl = ActOnDeclStmt(RangeGroup, RangeLoc, RangeLoc);
2542e5dd7070Spatrick if (RangeDecl.isInvalid()) {
2543ec727ea7Spatrick ActOnInitializerError(LoopVar);
2544e5dd7070Spatrick return StmtError();
2545e5dd7070Spatrick }
2546e5dd7070Spatrick
2547ec727ea7Spatrick StmtResult R = BuildCXXForRangeStmt(
2548e5dd7070Spatrick ForLoc, CoawaitLoc, InitStmt, ColonLoc, RangeDecl.get(),
2549e5dd7070Spatrick /*BeginStmt=*/nullptr, /*EndStmt=*/nullptr,
2550e5dd7070Spatrick /*Cond=*/nullptr, /*Inc=*/nullptr, DS, RParenLoc, Kind);
2551ec727ea7Spatrick if (R.isInvalid()) {
2552ec727ea7Spatrick ActOnInitializerError(LoopVar);
2553ec727ea7Spatrick return StmtError();
2554ec727ea7Spatrick }
2555ec727ea7Spatrick
2556ec727ea7Spatrick return R;
2557e5dd7070Spatrick }
2558e5dd7070Spatrick
2559e5dd7070Spatrick /// Create the initialization, compare, and increment steps for
2560e5dd7070Spatrick /// the range-based for loop expression.
2561e5dd7070Spatrick /// This function does not handle array-based for loops,
2562e5dd7070Spatrick /// which are created in Sema::BuildCXXForRangeStmt.
2563e5dd7070Spatrick ///
2564e5dd7070Spatrick /// \returns a ForRangeStatus indicating success or what kind of error occurred.
2565e5dd7070Spatrick /// BeginExpr and EndExpr are set and FRS_Success is returned on success;
2566e5dd7070Spatrick /// CandidateSet and BEF are set and some non-success value is returned on
2567e5dd7070Spatrick /// failure.
2568e5dd7070Spatrick static Sema::ForRangeStatus
BuildNonArrayForRange(Sema & SemaRef,Expr * BeginRange,Expr * EndRange,QualType RangeType,VarDecl * BeginVar,VarDecl * EndVar,SourceLocation ColonLoc,SourceLocation CoawaitLoc,OverloadCandidateSet * CandidateSet,ExprResult * BeginExpr,ExprResult * EndExpr,BeginEndFunction * BEF)2569e5dd7070Spatrick BuildNonArrayForRange(Sema &SemaRef, Expr *BeginRange, Expr *EndRange,
2570e5dd7070Spatrick QualType RangeType, VarDecl *BeginVar, VarDecl *EndVar,
2571e5dd7070Spatrick SourceLocation ColonLoc, SourceLocation CoawaitLoc,
2572e5dd7070Spatrick OverloadCandidateSet *CandidateSet, ExprResult *BeginExpr,
2573e5dd7070Spatrick ExprResult *EndExpr, BeginEndFunction *BEF) {
2574e5dd7070Spatrick DeclarationNameInfo BeginNameInfo(
2575e5dd7070Spatrick &SemaRef.PP.getIdentifierTable().get("begin"), ColonLoc);
2576e5dd7070Spatrick DeclarationNameInfo EndNameInfo(&SemaRef.PP.getIdentifierTable().get("end"),
2577e5dd7070Spatrick ColonLoc);
2578e5dd7070Spatrick
2579e5dd7070Spatrick LookupResult BeginMemberLookup(SemaRef, BeginNameInfo,
2580e5dd7070Spatrick Sema::LookupMemberName);
2581e5dd7070Spatrick LookupResult EndMemberLookup(SemaRef, EndNameInfo, Sema::LookupMemberName);
2582e5dd7070Spatrick
2583e5dd7070Spatrick auto BuildBegin = [&] {
2584e5dd7070Spatrick *BEF = BEF_begin;
2585e5dd7070Spatrick Sema::ForRangeStatus RangeStatus =
2586e5dd7070Spatrick SemaRef.BuildForRangeBeginEndCall(ColonLoc, ColonLoc, BeginNameInfo,
2587e5dd7070Spatrick BeginMemberLookup, CandidateSet,
2588e5dd7070Spatrick BeginRange, BeginExpr);
2589e5dd7070Spatrick
2590e5dd7070Spatrick if (RangeStatus != Sema::FRS_Success) {
2591e5dd7070Spatrick if (RangeStatus == Sema::FRS_DiagnosticIssued)
2592e5dd7070Spatrick SemaRef.Diag(BeginRange->getBeginLoc(), diag::note_in_for_range)
2593e5dd7070Spatrick << ColonLoc << BEF_begin << BeginRange->getType();
2594e5dd7070Spatrick return RangeStatus;
2595e5dd7070Spatrick }
2596e5dd7070Spatrick if (!CoawaitLoc.isInvalid()) {
2597e5dd7070Spatrick // FIXME: getCurScope() should not be used during template instantiation.
2598e5dd7070Spatrick // We should pick up the set of unqualified lookup results for operator
2599e5dd7070Spatrick // co_await during the initial parse.
2600e5dd7070Spatrick *BeginExpr = SemaRef.ActOnCoawaitExpr(SemaRef.getCurScope(), ColonLoc,
2601e5dd7070Spatrick BeginExpr->get());
2602e5dd7070Spatrick if (BeginExpr->isInvalid())
2603e5dd7070Spatrick return Sema::FRS_DiagnosticIssued;
2604e5dd7070Spatrick }
2605e5dd7070Spatrick if (FinishForRangeVarDecl(SemaRef, BeginVar, BeginExpr->get(), ColonLoc,
2606e5dd7070Spatrick diag::err_for_range_iter_deduction_failure)) {
2607e5dd7070Spatrick NoteForRangeBeginEndFunction(SemaRef, BeginExpr->get(), *BEF);
2608e5dd7070Spatrick return Sema::FRS_DiagnosticIssued;
2609e5dd7070Spatrick }
2610e5dd7070Spatrick return Sema::FRS_Success;
2611e5dd7070Spatrick };
2612e5dd7070Spatrick
2613e5dd7070Spatrick auto BuildEnd = [&] {
2614e5dd7070Spatrick *BEF = BEF_end;
2615e5dd7070Spatrick Sema::ForRangeStatus RangeStatus =
2616e5dd7070Spatrick SemaRef.BuildForRangeBeginEndCall(ColonLoc, ColonLoc, EndNameInfo,
2617e5dd7070Spatrick EndMemberLookup, CandidateSet,
2618e5dd7070Spatrick EndRange, EndExpr);
2619e5dd7070Spatrick if (RangeStatus != Sema::FRS_Success) {
2620e5dd7070Spatrick if (RangeStatus == Sema::FRS_DiagnosticIssued)
2621e5dd7070Spatrick SemaRef.Diag(EndRange->getBeginLoc(), diag::note_in_for_range)
2622e5dd7070Spatrick << ColonLoc << BEF_end << EndRange->getType();
2623e5dd7070Spatrick return RangeStatus;
2624e5dd7070Spatrick }
2625e5dd7070Spatrick if (FinishForRangeVarDecl(SemaRef, EndVar, EndExpr->get(), ColonLoc,
2626e5dd7070Spatrick diag::err_for_range_iter_deduction_failure)) {
2627e5dd7070Spatrick NoteForRangeBeginEndFunction(SemaRef, EndExpr->get(), *BEF);
2628e5dd7070Spatrick return Sema::FRS_DiagnosticIssued;
2629e5dd7070Spatrick }
2630e5dd7070Spatrick return Sema::FRS_Success;
2631e5dd7070Spatrick };
2632e5dd7070Spatrick
2633e5dd7070Spatrick if (CXXRecordDecl *D = RangeType->getAsCXXRecordDecl()) {
2634e5dd7070Spatrick // - if _RangeT is a class type, the unqualified-ids begin and end are
2635e5dd7070Spatrick // looked up in the scope of class _RangeT as if by class member access
2636e5dd7070Spatrick // lookup (3.4.5), and if either (or both) finds at least one
2637e5dd7070Spatrick // declaration, begin-expr and end-expr are __range.begin() and
2638e5dd7070Spatrick // __range.end(), respectively;
2639e5dd7070Spatrick SemaRef.LookupQualifiedName(BeginMemberLookup, D);
2640e5dd7070Spatrick if (BeginMemberLookup.isAmbiguous())
2641e5dd7070Spatrick return Sema::FRS_DiagnosticIssued;
2642e5dd7070Spatrick
2643e5dd7070Spatrick SemaRef.LookupQualifiedName(EndMemberLookup, D);
2644e5dd7070Spatrick if (EndMemberLookup.isAmbiguous())
2645e5dd7070Spatrick return Sema::FRS_DiagnosticIssued;
2646e5dd7070Spatrick
2647e5dd7070Spatrick if (BeginMemberLookup.empty() != EndMemberLookup.empty()) {
2648e5dd7070Spatrick // Look up the non-member form of the member we didn't find, first.
2649e5dd7070Spatrick // This way we prefer a "no viable 'end'" diagnostic over a "i found
2650e5dd7070Spatrick // a 'begin' but ignored it because there was no member 'end'"
2651e5dd7070Spatrick // diagnostic.
2652e5dd7070Spatrick auto BuildNonmember = [&](
2653e5dd7070Spatrick BeginEndFunction BEFFound, LookupResult &Found,
2654e5dd7070Spatrick llvm::function_ref<Sema::ForRangeStatus()> BuildFound,
2655e5dd7070Spatrick llvm::function_ref<Sema::ForRangeStatus()> BuildNotFound) {
2656e5dd7070Spatrick LookupResult OldFound = std::move(Found);
2657e5dd7070Spatrick Found.clear();
2658e5dd7070Spatrick
2659e5dd7070Spatrick if (Sema::ForRangeStatus Result = BuildNotFound())
2660e5dd7070Spatrick return Result;
2661e5dd7070Spatrick
2662e5dd7070Spatrick switch (BuildFound()) {
2663e5dd7070Spatrick case Sema::FRS_Success:
2664e5dd7070Spatrick return Sema::FRS_Success;
2665e5dd7070Spatrick
2666e5dd7070Spatrick case Sema::FRS_NoViableFunction:
2667e5dd7070Spatrick CandidateSet->NoteCandidates(
2668e5dd7070Spatrick PartialDiagnosticAt(BeginRange->getBeginLoc(),
2669e5dd7070Spatrick SemaRef.PDiag(diag::err_for_range_invalid)
2670e5dd7070Spatrick << BeginRange->getType() << BEFFound),
2671e5dd7070Spatrick SemaRef, OCD_AllCandidates, BeginRange);
2672*12c85518Srobert [[fallthrough]];
2673e5dd7070Spatrick
2674e5dd7070Spatrick case Sema::FRS_DiagnosticIssued:
2675e5dd7070Spatrick for (NamedDecl *D : OldFound) {
2676e5dd7070Spatrick SemaRef.Diag(D->getLocation(),
2677e5dd7070Spatrick diag::note_for_range_member_begin_end_ignored)
2678e5dd7070Spatrick << BeginRange->getType() << BEFFound;
2679e5dd7070Spatrick }
2680e5dd7070Spatrick return Sema::FRS_DiagnosticIssued;
2681e5dd7070Spatrick }
2682e5dd7070Spatrick llvm_unreachable("unexpected ForRangeStatus");
2683e5dd7070Spatrick };
2684e5dd7070Spatrick if (BeginMemberLookup.empty())
2685e5dd7070Spatrick return BuildNonmember(BEF_end, EndMemberLookup, BuildEnd, BuildBegin);
2686e5dd7070Spatrick return BuildNonmember(BEF_begin, BeginMemberLookup, BuildBegin, BuildEnd);
2687e5dd7070Spatrick }
2688e5dd7070Spatrick } else {
2689e5dd7070Spatrick // - otherwise, begin-expr and end-expr are begin(__range) and
2690e5dd7070Spatrick // end(__range), respectively, where begin and end are looked up with
2691e5dd7070Spatrick // argument-dependent lookup (3.4.2). For the purposes of this name
2692e5dd7070Spatrick // lookup, namespace std is an associated namespace.
2693e5dd7070Spatrick }
2694e5dd7070Spatrick
2695e5dd7070Spatrick if (Sema::ForRangeStatus Result = BuildBegin())
2696e5dd7070Spatrick return Result;
2697e5dd7070Spatrick return BuildEnd();
2698e5dd7070Spatrick }
2699e5dd7070Spatrick
2700e5dd7070Spatrick /// Speculatively attempt to dereference an invalid range expression.
2701e5dd7070Spatrick /// If the attempt fails, this function will return a valid, null StmtResult
2702e5dd7070Spatrick /// and emit no diagnostics.
RebuildForRangeWithDereference(Sema & SemaRef,Scope * S,SourceLocation ForLoc,SourceLocation CoawaitLoc,Stmt * InitStmt,Stmt * LoopVarDecl,SourceLocation ColonLoc,Expr * Range,SourceLocation RangeLoc,SourceLocation RParenLoc)2703e5dd7070Spatrick static StmtResult RebuildForRangeWithDereference(Sema &SemaRef, Scope *S,
2704e5dd7070Spatrick SourceLocation ForLoc,
2705e5dd7070Spatrick SourceLocation CoawaitLoc,
2706e5dd7070Spatrick Stmt *InitStmt,
2707e5dd7070Spatrick Stmt *LoopVarDecl,
2708e5dd7070Spatrick SourceLocation ColonLoc,
2709e5dd7070Spatrick Expr *Range,
2710e5dd7070Spatrick SourceLocation RangeLoc,
2711e5dd7070Spatrick SourceLocation RParenLoc) {
2712e5dd7070Spatrick // Determine whether we can rebuild the for-range statement with a
2713e5dd7070Spatrick // dereferenced range expression.
2714e5dd7070Spatrick ExprResult AdjustedRange;
2715e5dd7070Spatrick {
2716e5dd7070Spatrick Sema::SFINAETrap Trap(SemaRef);
2717e5dd7070Spatrick
2718e5dd7070Spatrick AdjustedRange = SemaRef.BuildUnaryOp(S, RangeLoc, UO_Deref, Range);
2719e5dd7070Spatrick if (AdjustedRange.isInvalid())
2720e5dd7070Spatrick return StmtResult();
2721e5dd7070Spatrick
2722e5dd7070Spatrick StmtResult SR = SemaRef.ActOnCXXForRangeStmt(
2723e5dd7070Spatrick S, ForLoc, CoawaitLoc, InitStmt, LoopVarDecl, ColonLoc,
2724e5dd7070Spatrick AdjustedRange.get(), RParenLoc, Sema::BFRK_Check);
2725e5dd7070Spatrick if (SR.isInvalid())
2726e5dd7070Spatrick return StmtResult();
2727e5dd7070Spatrick }
2728e5dd7070Spatrick
2729e5dd7070Spatrick // The attempt to dereference worked well enough that it could produce a valid
2730e5dd7070Spatrick // loop. Produce a fixit, and rebuild the loop with diagnostics enabled, in
2731e5dd7070Spatrick // case there are any other (non-fatal) problems with it.
2732e5dd7070Spatrick SemaRef.Diag(RangeLoc, diag::err_for_range_dereference)
2733e5dd7070Spatrick << Range->getType() << FixItHint::CreateInsertion(RangeLoc, "*");
2734e5dd7070Spatrick return SemaRef.ActOnCXXForRangeStmt(
2735e5dd7070Spatrick S, ForLoc, CoawaitLoc, InitStmt, LoopVarDecl, ColonLoc,
2736e5dd7070Spatrick AdjustedRange.get(), RParenLoc, Sema::BFRK_Rebuild);
2737e5dd7070Spatrick }
2738e5dd7070Spatrick
2739e5dd7070Spatrick /// BuildCXXForRangeStmt - Build or instantiate a C++11 for-range statement.
BuildCXXForRangeStmt(SourceLocation ForLoc,SourceLocation CoawaitLoc,Stmt * InitStmt,SourceLocation ColonLoc,Stmt * RangeDecl,Stmt * Begin,Stmt * End,Expr * Cond,Expr * Inc,Stmt * LoopVarDecl,SourceLocation RParenLoc,BuildForRangeKind Kind)2740e5dd7070Spatrick StmtResult Sema::BuildCXXForRangeStmt(SourceLocation ForLoc,
2741e5dd7070Spatrick SourceLocation CoawaitLoc, Stmt *InitStmt,
2742e5dd7070Spatrick SourceLocation ColonLoc, Stmt *RangeDecl,
2743e5dd7070Spatrick Stmt *Begin, Stmt *End, Expr *Cond,
2744e5dd7070Spatrick Expr *Inc, Stmt *LoopVarDecl,
2745e5dd7070Spatrick SourceLocation RParenLoc,
2746e5dd7070Spatrick BuildForRangeKind Kind) {
2747e5dd7070Spatrick // FIXME: This should not be used during template instantiation. We should
2748e5dd7070Spatrick // pick up the set of unqualified lookup results for the != and + operators
2749e5dd7070Spatrick // in the initial parse.
2750e5dd7070Spatrick //
2751e5dd7070Spatrick // Testcase (accepts-invalid):
2752e5dd7070Spatrick // template<typename T> void f() { for (auto x : T()) {} }
2753e5dd7070Spatrick // namespace N { struct X { X begin(); X end(); int operator*(); }; }
2754e5dd7070Spatrick // bool operator!=(N::X, N::X); void operator++(N::X);
2755e5dd7070Spatrick // void g() { f<N::X>(); }
2756e5dd7070Spatrick Scope *S = getCurScope();
2757e5dd7070Spatrick
2758e5dd7070Spatrick DeclStmt *RangeDS = cast<DeclStmt>(RangeDecl);
2759e5dd7070Spatrick VarDecl *RangeVar = cast<VarDecl>(RangeDS->getSingleDecl());
2760e5dd7070Spatrick QualType RangeVarType = RangeVar->getType();
2761e5dd7070Spatrick
2762e5dd7070Spatrick DeclStmt *LoopVarDS = cast<DeclStmt>(LoopVarDecl);
2763e5dd7070Spatrick VarDecl *LoopVar = cast<VarDecl>(LoopVarDS->getSingleDecl());
2764e5dd7070Spatrick
2765e5dd7070Spatrick StmtResult BeginDeclStmt = Begin;
2766e5dd7070Spatrick StmtResult EndDeclStmt = End;
2767e5dd7070Spatrick ExprResult NotEqExpr = Cond, IncrExpr = Inc;
2768e5dd7070Spatrick
2769e5dd7070Spatrick if (RangeVarType->isDependentType()) {
2770e5dd7070Spatrick // The range is implicitly used as a placeholder when it is dependent.
2771e5dd7070Spatrick RangeVar->markUsed(Context);
2772e5dd7070Spatrick
2773e5dd7070Spatrick // Deduce any 'auto's in the loop variable as 'DependentTy'. We'll fill
2774e5dd7070Spatrick // them in properly when we instantiate the loop.
2775e5dd7070Spatrick if (!LoopVar->isInvalidDecl() && Kind != BFRK_Check) {
2776e5dd7070Spatrick if (auto *DD = dyn_cast<DecompositionDecl>(LoopVar))
2777e5dd7070Spatrick for (auto *Binding : DD->bindings())
2778e5dd7070Spatrick Binding->setType(Context.DependentTy);
2779*12c85518Srobert LoopVar->setType(SubstAutoTypeDependent(LoopVar->getType()));
2780e5dd7070Spatrick }
2781e5dd7070Spatrick } else if (!BeginDeclStmt.get()) {
2782e5dd7070Spatrick SourceLocation RangeLoc = RangeVar->getLocation();
2783e5dd7070Spatrick
2784e5dd7070Spatrick const QualType RangeVarNonRefType = RangeVarType.getNonReferenceType();
2785e5dd7070Spatrick
2786e5dd7070Spatrick ExprResult BeginRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType,
2787e5dd7070Spatrick VK_LValue, ColonLoc);
2788e5dd7070Spatrick if (BeginRangeRef.isInvalid())
2789e5dd7070Spatrick return StmtError();
2790e5dd7070Spatrick
2791e5dd7070Spatrick ExprResult EndRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType,
2792e5dd7070Spatrick VK_LValue, ColonLoc);
2793e5dd7070Spatrick if (EndRangeRef.isInvalid())
2794e5dd7070Spatrick return StmtError();
2795e5dd7070Spatrick
2796e5dd7070Spatrick QualType AutoType = Context.getAutoDeductType();
2797e5dd7070Spatrick Expr *Range = RangeVar->getInit();
2798e5dd7070Spatrick if (!Range)
2799e5dd7070Spatrick return StmtError();
2800e5dd7070Spatrick QualType RangeType = Range->getType();
2801e5dd7070Spatrick
2802e5dd7070Spatrick if (RequireCompleteType(RangeLoc, RangeType,
2803e5dd7070Spatrick diag::err_for_range_incomplete_type))
2804e5dd7070Spatrick return StmtError();
2805e5dd7070Spatrick
2806e5dd7070Spatrick // Build auto __begin = begin-expr, __end = end-expr.
2807e5dd7070Spatrick // Divide by 2, since the variables are in the inner scope (loop body).
2808e5dd7070Spatrick const auto DepthStr = std::to_string(S->getDepth() / 2);
2809e5dd7070Spatrick VarDecl *BeginVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType,
2810e5dd7070Spatrick std::string("__begin") + DepthStr);
2811e5dd7070Spatrick VarDecl *EndVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType,
2812e5dd7070Spatrick std::string("__end") + DepthStr);
2813e5dd7070Spatrick
2814e5dd7070Spatrick // Build begin-expr and end-expr and attach to __begin and __end variables.
2815e5dd7070Spatrick ExprResult BeginExpr, EndExpr;
2816e5dd7070Spatrick if (const ArrayType *UnqAT = RangeType->getAsArrayTypeUnsafe()) {
2817e5dd7070Spatrick // - if _RangeT is an array type, begin-expr and end-expr are __range and
2818e5dd7070Spatrick // __range + __bound, respectively, where __bound is the array bound. If
2819e5dd7070Spatrick // _RangeT is an array of unknown size or an array of incomplete type,
2820e5dd7070Spatrick // the program is ill-formed;
2821e5dd7070Spatrick
2822e5dd7070Spatrick // begin-expr is __range.
2823e5dd7070Spatrick BeginExpr = BeginRangeRef;
2824e5dd7070Spatrick if (!CoawaitLoc.isInvalid()) {
2825e5dd7070Spatrick BeginExpr = ActOnCoawaitExpr(S, ColonLoc, BeginExpr.get());
2826e5dd7070Spatrick if (BeginExpr.isInvalid())
2827e5dd7070Spatrick return StmtError();
2828e5dd7070Spatrick }
2829e5dd7070Spatrick if (FinishForRangeVarDecl(*this, BeginVar, BeginRangeRef.get(), ColonLoc,
2830e5dd7070Spatrick diag::err_for_range_iter_deduction_failure)) {
2831e5dd7070Spatrick NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2832e5dd7070Spatrick return StmtError();
2833e5dd7070Spatrick }
2834e5dd7070Spatrick
2835e5dd7070Spatrick // Find the array bound.
2836e5dd7070Spatrick ExprResult BoundExpr;
2837e5dd7070Spatrick if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(UnqAT))
2838e5dd7070Spatrick BoundExpr = IntegerLiteral::Create(
2839e5dd7070Spatrick Context, CAT->getSize(), Context.getPointerDiffType(), RangeLoc);
2840e5dd7070Spatrick else if (const VariableArrayType *VAT =
2841e5dd7070Spatrick dyn_cast<VariableArrayType>(UnqAT)) {
2842e5dd7070Spatrick // For a variably modified type we can't just use the expression within
2843e5dd7070Spatrick // the array bounds, since we don't want that to be re-evaluated here.
2844e5dd7070Spatrick // Rather, we need to determine what it was when the array was first
2845e5dd7070Spatrick // created - so we resort to using sizeof(vla)/sizeof(element).
2846e5dd7070Spatrick // For e.g.
2847e5dd7070Spatrick // void f(int b) {
2848e5dd7070Spatrick // int vla[b];
2849e5dd7070Spatrick // b = -1; <-- This should not affect the num of iterations below
2850e5dd7070Spatrick // for (int &c : vla) { .. }
2851e5dd7070Spatrick // }
2852e5dd7070Spatrick
2853e5dd7070Spatrick // FIXME: This results in codegen generating IR that recalculates the
2854e5dd7070Spatrick // run-time number of elements (as opposed to just using the IR Value
2855e5dd7070Spatrick // that corresponds to the run-time value of each bound that was
2856e5dd7070Spatrick // generated when the array was created.) If this proves too embarrassing
2857e5dd7070Spatrick // even for unoptimized IR, consider passing a magic-value/cookie to
2858e5dd7070Spatrick // codegen that then knows to simply use that initial llvm::Value (that
2859e5dd7070Spatrick // corresponds to the bound at time of array creation) within
2860e5dd7070Spatrick // getelementptr. But be prepared to pay the price of increasing a
2861e5dd7070Spatrick // customized form of coupling between the two components - which could
2862e5dd7070Spatrick // be hard to maintain as the codebase evolves.
2863e5dd7070Spatrick
2864e5dd7070Spatrick ExprResult SizeOfVLAExprR = ActOnUnaryExprOrTypeTraitExpr(
2865e5dd7070Spatrick EndVar->getLocation(), UETT_SizeOf,
2866e5dd7070Spatrick /*IsType=*/true,
2867e5dd7070Spatrick CreateParsedType(VAT->desugar(), Context.getTrivialTypeSourceInfo(
2868e5dd7070Spatrick VAT->desugar(), RangeLoc))
2869e5dd7070Spatrick .getAsOpaquePtr(),
2870e5dd7070Spatrick EndVar->getSourceRange());
2871e5dd7070Spatrick if (SizeOfVLAExprR.isInvalid())
2872e5dd7070Spatrick return StmtError();
2873e5dd7070Spatrick
2874e5dd7070Spatrick ExprResult SizeOfEachElementExprR = ActOnUnaryExprOrTypeTraitExpr(
2875e5dd7070Spatrick EndVar->getLocation(), UETT_SizeOf,
2876e5dd7070Spatrick /*IsType=*/true,
2877e5dd7070Spatrick CreateParsedType(VAT->desugar(),
2878e5dd7070Spatrick Context.getTrivialTypeSourceInfo(
2879e5dd7070Spatrick VAT->getElementType(), RangeLoc))
2880e5dd7070Spatrick .getAsOpaquePtr(),
2881e5dd7070Spatrick EndVar->getSourceRange());
2882e5dd7070Spatrick if (SizeOfEachElementExprR.isInvalid())
2883e5dd7070Spatrick return StmtError();
2884e5dd7070Spatrick
2885e5dd7070Spatrick BoundExpr =
2886e5dd7070Spatrick ActOnBinOp(S, EndVar->getLocation(), tok::slash,
2887e5dd7070Spatrick SizeOfVLAExprR.get(), SizeOfEachElementExprR.get());
2888e5dd7070Spatrick if (BoundExpr.isInvalid())
2889e5dd7070Spatrick return StmtError();
2890e5dd7070Spatrick
2891e5dd7070Spatrick } else {
2892e5dd7070Spatrick // Can't be a DependentSizedArrayType or an IncompleteArrayType since
2893e5dd7070Spatrick // UnqAT is not incomplete and Range is not type-dependent.
2894e5dd7070Spatrick llvm_unreachable("Unexpected array type in for-range");
2895e5dd7070Spatrick }
2896e5dd7070Spatrick
2897e5dd7070Spatrick // end-expr is __range + __bound.
2898e5dd7070Spatrick EndExpr = ActOnBinOp(S, ColonLoc, tok::plus, EndRangeRef.get(),
2899e5dd7070Spatrick BoundExpr.get());
2900e5dd7070Spatrick if (EndExpr.isInvalid())
2901e5dd7070Spatrick return StmtError();
2902e5dd7070Spatrick if (FinishForRangeVarDecl(*this, EndVar, EndExpr.get(), ColonLoc,
2903e5dd7070Spatrick diag::err_for_range_iter_deduction_failure)) {
2904e5dd7070Spatrick NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
2905e5dd7070Spatrick return StmtError();
2906e5dd7070Spatrick }
2907e5dd7070Spatrick } else {
2908e5dd7070Spatrick OverloadCandidateSet CandidateSet(RangeLoc,
2909e5dd7070Spatrick OverloadCandidateSet::CSK_Normal);
2910e5dd7070Spatrick BeginEndFunction BEFFailure;
2911e5dd7070Spatrick ForRangeStatus RangeStatus = BuildNonArrayForRange(
2912e5dd7070Spatrick *this, BeginRangeRef.get(), EndRangeRef.get(), RangeType, BeginVar,
2913e5dd7070Spatrick EndVar, ColonLoc, CoawaitLoc, &CandidateSet, &BeginExpr, &EndExpr,
2914e5dd7070Spatrick &BEFFailure);
2915e5dd7070Spatrick
2916e5dd7070Spatrick if (Kind == BFRK_Build && RangeStatus == FRS_NoViableFunction &&
2917e5dd7070Spatrick BEFFailure == BEF_begin) {
2918e5dd7070Spatrick // If the range is being built from an array parameter, emit a
2919e5dd7070Spatrick // a diagnostic that it is being treated as a pointer.
2920e5dd7070Spatrick if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Range)) {
2921e5dd7070Spatrick if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DRE->getDecl())) {
2922e5dd7070Spatrick QualType ArrayTy = PVD->getOriginalType();
2923e5dd7070Spatrick QualType PointerTy = PVD->getType();
2924e5dd7070Spatrick if (PointerTy->isPointerType() && ArrayTy->isArrayType()) {
2925e5dd7070Spatrick Diag(Range->getBeginLoc(), diag::err_range_on_array_parameter)
2926e5dd7070Spatrick << RangeLoc << PVD << ArrayTy << PointerTy;
2927e5dd7070Spatrick Diag(PVD->getLocation(), diag::note_declared_at);
2928e5dd7070Spatrick return StmtError();
2929e5dd7070Spatrick }
2930e5dd7070Spatrick }
2931e5dd7070Spatrick }
2932e5dd7070Spatrick
2933e5dd7070Spatrick // If building the range failed, try dereferencing the range expression
2934e5dd7070Spatrick // unless a diagnostic was issued or the end function is problematic.
2935e5dd7070Spatrick StmtResult SR = RebuildForRangeWithDereference(*this, S, ForLoc,
2936e5dd7070Spatrick CoawaitLoc, InitStmt,
2937e5dd7070Spatrick LoopVarDecl, ColonLoc,
2938e5dd7070Spatrick Range, RangeLoc,
2939e5dd7070Spatrick RParenLoc);
2940e5dd7070Spatrick if (SR.isInvalid() || SR.isUsable())
2941e5dd7070Spatrick return SR;
2942e5dd7070Spatrick }
2943e5dd7070Spatrick
2944e5dd7070Spatrick // Otherwise, emit diagnostics if we haven't already.
2945e5dd7070Spatrick if (RangeStatus == FRS_NoViableFunction) {
2946e5dd7070Spatrick Expr *Range = BEFFailure ? EndRangeRef.get() : BeginRangeRef.get();
2947e5dd7070Spatrick CandidateSet.NoteCandidates(
2948e5dd7070Spatrick PartialDiagnosticAt(Range->getBeginLoc(),
2949e5dd7070Spatrick PDiag(diag::err_for_range_invalid)
2950e5dd7070Spatrick << RangeLoc << Range->getType()
2951e5dd7070Spatrick << BEFFailure),
2952e5dd7070Spatrick *this, OCD_AllCandidates, Range);
2953e5dd7070Spatrick }
2954e5dd7070Spatrick // Return an error if no fix was discovered.
2955e5dd7070Spatrick if (RangeStatus != FRS_Success)
2956e5dd7070Spatrick return StmtError();
2957e5dd7070Spatrick }
2958e5dd7070Spatrick
2959e5dd7070Spatrick assert(!BeginExpr.isInvalid() && !EndExpr.isInvalid() &&
2960e5dd7070Spatrick "invalid range expression in for loop");
2961e5dd7070Spatrick
2962e5dd7070Spatrick // C++11 [dcl.spec.auto]p7: BeginType and EndType must be the same.
2963e5dd7070Spatrick // C++1z removes this restriction.
2964e5dd7070Spatrick QualType BeginType = BeginVar->getType(), EndType = EndVar->getType();
2965e5dd7070Spatrick if (!Context.hasSameType(BeginType, EndType)) {
2966e5dd7070Spatrick Diag(RangeLoc, getLangOpts().CPlusPlus17
2967e5dd7070Spatrick ? diag::warn_for_range_begin_end_types_differ
2968e5dd7070Spatrick : diag::ext_for_range_begin_end_types_differ)
2969e5dd7070Spatrick << BeginType << EndType;
2970e5dd7070Spatrick NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2971e5dd7070Spatrick NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
2972e5dd7070Spatrick }
2973e5dd7070Spatrick
2974e5dd7070Spatrick BeginDeclStmt =
2975e5dd7070Spatrick ActOnDeclStmt(ConvertDeclToDeclGroup(BeginVar), ColonLoc, ColonLoc);
2976e5dd7070Spatrick EndDeclStmt =
2977e5dd7070Spatrick ActOnDeclStmt(ConvertDeclToDeclGroup(EndVar), ColonLoc, ColonLoc);
2978e5dd7070Spatrick
2979e5dd7070Spatrick const QualType BeginRefNonRefType = BeginType.getNonReferenceType();
2980e5dd7070Spatrick ExprResult BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
2981e5dd7070Spatrick VK_LValue, ColonLoc);
2982e5dd7070Spatrick if (BeginRef.isInvalid())
2983e5dd7070Spatrick return StmtError();
2984e5dd7070Spatrick
2985e5dd7070Spatrick ExprResult EndRef = BuildDeclRefExpr(EndVar, EndType.getNonReferenceType(),
2986e5dd7070Spatrick VK_LValue, ColonLoc);
2987e5dd7070Spatrick if (EndRef.isInvalid())
2988e5dd7070Spatrick return StmtError();
2989e5dd7070Spatrick
2990e5dd7070Spatrick // Build and check __begin != __end expression.
2991e5dd7070Spatrick NotEqExpr = ActOnBinOp(S, ColonLoc, tok::exclaimequal,
2992e5dd7070Spatrick BeginRef.get(), EndRef.get());
2993e5dd7070Spatrick if (!NotEqExpr.isInvalid())
2994e5dd7070Spatrick NotEqExpr = CheckBooleanCondition(ColonLoc, NotEqExpr.get());
2995e5dd7070Spatrick if (!NotEqExpr.isInvalid())
2996e5dd7070Spatrick NotEqExpr =
2997e5dd7070Spatrick ActOnFinishFullExpr(NotEqExpr.get(), /*DiscardedValue*/ false);
2998e5dd7070Spatrick if (NotEqExpr.isInvalid()) {
2999e5dd7070Spatrick Diag(RangeLoc, diag::note_for_range_invalid_iterator)
3000e5dd7070Spatrick << RangeLoc << 0 << BeginRangeRef.get()->getType();
3001e5dd7070Spatrick NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
3002e5dd7070Spatrick if (!Context.hasSameType(BeginType, EndType))
3003e5dd7070Spatrick NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
3004e5dd7070Spatrick return StmtError();
3005e5dd7070Spatrick }
3006e5dd7070Spatrick
3007e5dd7070Spatrick // Build and check ++__begin expression.
3008e5dd7070Spatrick BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
3009e5dd7070Spatrick VK_LValue, ColonLoc);
3010e5dd7070Spatrick if (BeginRef.isInvalid())
3011e5dd7070Spatrick return StmtError();
3012e5dd7070Spatrick
3013e5dd7070Spatrick IncrExpr = ActOnUnaryOp(S, ColonLoc, tok::plusplus, BeginRef.get());
3014e5dd7070Spatrick if (!IncrExpr.isInvalid() && CoawaitLoc.isValid())
3015e5dd7070Spatrick // FIXME: getCurScope() should not be used during template instantiation.
3016e5dd7070Spatrick // We should pick up the set of unqualified lookup results for operator
3017e5dd7070Spatrick // co_await during the initial parse.
3018e5dd7070Spatrick IncrExpr = ActOnCoawaitExpr(S, CoawaitLoc, IncrExpr.get());
3019e5dd7070Spatrick if (!IncrExpr.isInvalid())
3020e5dd7070Spatrick IncrExpr = ActOnFinishFullExpr(IncrExpr.get(), /*DiscardedValue*/ false);
3021e5dd7070Spatrick if (IncrExpr.isInvalid()) {
3022e5dd7070Spatrick Diag(RangeLoc, diag::note_for_range_invalid_iterator)
3023e5dd7070Spatrick << RangeLoc << 2 << BeginRangeRef.get()->getType() ;
3024e5dd7070Spatrick NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
3025e5dd7070Spatrick return StmtError();
3026e5dd7070Spatrick }
3027e5dd7070Spatrick
3028e5dd7070Spatrick // Build and check *__begin expression.
3029e5dd7070Spatrick BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
3030e5dd7070Spatrick VK_LValue, ColonLoc);
3031e5dd7070Spatrick if (BeginRef.isInvalid())
3032e5dd7070Spatrick return StmtError();
3033e5dd7070Spatrick
3034e5dd7070Spatrick ExprResult DerefExpr = ActOnUnaryOp(S, ColonLoc, tok::star, BeginRef.get());
3035e5dd7070Spatrick if (DerefExpr.isInvalid()) {
3036e5dd7070Spatrick Diag(RangeLoc, diag::note_for_range_invalid_iterator)
3037e5dd7070Spatrick << RangeLoc << 1 << BeginRangeRef.get()->getType();
3038e5dd7070Spatrick NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
3039e5dd7070Spatrick return StmtError();
3040e5dd7070Spatrick }
3041e5dd7070Spatrick
3042e5dd7070Spatrick // Attach *__begin as initializer for VD. Don't touch it if we're just
3043e5dd7070Spatrick // trying to determine whether this would be a valid range.
3044e5dd7070Spatrick if (!LoopVar->isInvalidDecl() && Kind != BFRK_Check) {
3045e5dd7070Spatrick AddInitializerToDecl(LoopVar, DerefExpr.get(), /*DirectInit=*/false);
3046ec727ea7Spatrick if (LoopVar->isInvalidDecl() ||
3047ec727ea7Spatrick (LoopVar->getInit() && LoopVar->getInit()->containsErrors()))
3048e5dd7070Spatrick NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
3049e5dd7070Spatrick }
3050e5dd7070Spatrick }
3051e5dd7070Spatrick
3052e5dd7070Spatrick // Don't bother to actually allocate the result if we're just trying to
3053e5dd7070Spatrick // determine whether it would be valid.
3054e5dd7070Spatrick if (Kind == BFRK_Check)
3055e5dd7070Spatrick return StmtResult();
3056e5dd7070Spatrick
3057e5dd7070Spatrick // In OpenMP loop region loop control variable must be private. Perform
3058e5dd7070Spatrick // analysis of first part (if any).
3059e5dd7070Spatrick if (getLangOpts().OpenMP >= 50 && BeginDeclStmt.isUsable())
3060e5dd7070Spatrick ActOnOpenMPLoopInitialization(ForLoc, BeginDeclStmt.get());
3061e5dd7070Spatrick
3062e5dd7070Spatrick return new (Context) CXXForRangeStmt(
3063e5dd7070Spatrick InitStmt, RangeDS, cast_or_null<DeclStmt>(BeginDeclStmt.get()),
3064e5dd7070Spatrick cast_or_null<DeclStmt>(EndDeclStmt.get()), NotEqExpr.get(),
3065e5dd7070Spatrick IncrExpr.get(), LoopVarDS, /*Body=*/nullptr, ForLoc, CoawaitLoc,
3066e5dd7070Spatrick ColonLoc, RParenLoc);
3067e5dd7070Spatrick }
3068e5dd7070Spatrick
3069e5dd7070Spatrick /// FinishObjCForCollectionStmt - Attach the body to a objective-C foreach
3070e5dd7070Spatrick /// statement.
FinishObjCForCollectionStmt(Stmt * S,Stmt * B)3071e5dd7070Spatrick StmtResult Sema::FinishObjCForCollectionStmt(Stmt *S, Stmt *B) {
3072e5dd7070Spatrick if (!S || !B)
3073e5dd7070Spatrick return StmtError();
3074e5dd7070Spatrick ObjCForCollectionStmt * ForStmt = cast<ObjCForCollectionStmt>(S);
3075e5dd7070Spatrick
3076e5dd7070Spatrick ForStmt->setBody(B);
3077e5dd7070Spatrick return S;
3078e5dd7070Spatrick }
3079e5dd7070Spatrick
3080e5dd7070Spatrick // Warn when the loop variable is a const reference that creates a copy.
3081e5dd7070Spatrick // Suggest using the non-reference type for copies. If a copy can be prevented
3082e5dd7070Spatrick // suggest the const reference type that would do so.
3083e5dd7070Spatrick // For instance, given "for (const &Foo : Range)", suggest
3084e5dd7070Spatrick // "for (const Foo : Range)" to denote a copy is made for the loop. If
3085e5dd7070Spatrick // possible, also suggest "for (const &Bar : Range)" if this type prevents
3086e5dd7070Spatrick // the copy altogether.
DiagnoseForRangeReferenceVariableCopies(Sema & SemaRef,const VarDecl * VD,QualType RangeInitType)3087e5dd7070Spatrick static void DiagnoseForRangeReferenceVariableCopies(Sema &SemaRef,
3088e5dd7070Spatrick const VarDecl *VD,
3089e5dd7070Spatrick QualType RangeInitType) {
3090e5dd7070Spatrick const Expr *InitExpr = VD->getInit();
3091e5dd7070Spatrick if (!InitExpr)
3092e5dd7070Spatrick return;
3093e5dd7070Spatrick
3094e5dd7070Spatrick QualType VariableType = VD->getType();
3095e5dd7070Spatrick
3096e5dd7070Spatrick if (auto Cleanups = dyn_cast<ExprWithCleanups>(InitExpr))
3097e5dd7070Spatrick if (!Cleanups->cleanupsHaveSideEffects())
3098e5dd7070Spatrick InitExpr = Cleanups->getSubExpr();
3099e5dd7070Spatrick
3100e5dd7070Spatrick const MaterializeTemporaryExpr *MTE =
3101e5dd7070Spatrick dyn_cast<MaterializeTemporaryExpr>(InitExpr);
3102e5dd7070Spatrick
3103e5dd7070Spatrick // No copy made.
3104e5dd7070Spatrick if (!MTE)
3105e5dd7070Spatrick return;
3106e5dd7070Spatrick
3107e5dd7070Spatrick const Expr *E = MTE->getSubExpr()->IgnoreImpCasts();
3108e5dd7070Spatrick
3109e5dd7070Spatrick // Searching for either UnaryOperator for dereference of a pointer or
3110e5dd7070Spatrick // CXXOperatorCallExpr for handling iterators.
3111e5dd7070Spatrick while (!isa<CXXOperatorCallExpr>(E) && !isa<UnaryOperator>(E)) {
3112e5dd7070Spatrick if (const CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(E)) {
3113e5dd7070Spatrick E = CCE->getArg(0);
3114e5dd7070Spatrick } else if (const CXXMemberCallExpr *Call = dyn_cast<CXXMemberCallExpr>(E)) {
3115e5dd7070Spatrick const MemberExpr *ME = cast<MemberExpr>(Call->getCallee());
3116e5dd7070Spatrick E = ME->getBase();
3117e5dd7070Spatrick } else {
3118e5dd7070Spatrick const MaterializeTemporaryExpr *MTE = cast<MaterializeTemporaryExpr>(E);
3119e5dd7070Spatrick E = MTE->getSubExpr();
3120e5dd7070Spatrick }
3121e5dd7070Spatrick E = E->IgnoreImpCasts();
3122e5dd7070Spatrick }
3123e5dd7070Spatrick
3124ec727ea7Spatrick QualType ReferenceReturnType;
3125e5dd7070Spatrick if (isa<UnaryOperator>(E)) {
3126ec727ea7Spatrick ReferenceReturnType = SemaRef.Context.getLValueReferenceType(E->getType());
3127e5dd7070Spatrick } else {
3128e5dd7070Spatrick const CXXOperatorCallExpr *Call = cast<CXXOperatorCallExpr>(E);
3129e5dd7070Spatrick const FunctionDecl *FD = Call->getDirectCallee();
3130e5dd7070Spatrick QualType ReturnType = FD->getReturnType();
3131ec727ea7Spatrick if (ReturnType->isReferenceType())
3132ec727ea7Spatrick ReferenceReturnType = ReturnType;
3133e5dd7070Spatrick }
3134e5dd7070Spatrick
3135ec727ea7Spatrick if (!ReferenceReturnType.isNull()) {
3136e5dd7070Spatrick // Loop variable creates a temporary. Suggest either to go with
3137e5dd7070Spatrick // non-reference loop variable to indicate a copy is made, or
3138ec727ea7Spatrick // the correct type to bind a const reference.
3139ec727ea7Spatrick SemaRef.Diag(VD->getLocation(),
3140ec727ea7Spatrick diag::warn_for_range_const_ref_binds_temp_built_from_ref)
3141ec727ea7Spatrick << VD << VariableType << ReferenceReturnType;
3142e5dd7070Spatrick QualType NonReferenceType = VariableType.getNonReferenceType();
3143e5dd7070Spatrick NonReferenceType.removeLocalConst();
3144e5dd7070Spatrick QualType NewReferenceType =
3145e5dd7070Spatrick SemaRef.Context.getLValueReferenceType(E->getType().withConst());
3146e5dd7070Spatrick SemaRef.Diag(VD->getBeginLoc(), diag::note_use_type_or_non_reference)
3147e5dd7070Spatrick << NonReferenceType << NewReferenceType << VD->getSourceRange()
3148e5dd7070Spatrick << FixItHint::CreateRemoval(VD->getTypeSpecEndLoc());
3149e5dd7070Spatrick } else if (!VariableType->isRValueReferenceType()) {
3150e5dd7070Spatrick // The range always returns a copy, so a temporary is always created.
3151e5dd7070Spatrick // Suggest removing the reference from the loop variable.
3152e5dd7070Spatrick // If the type is a rvalue reference do not warn since that changes the
3153e5dd7070Spatrick // semantic of the code.
3154ec727ea7Spatrick SemaRef.Diag(VD->getLocation(), diag::warn_for_range_ref_binds_ret_temp)
3155e5dd7070Spatrick << VD << RangeInitType;
3156e5dd7070Spatrick QualType NonReferenceType = VariableType.getNonReferenceType();
3157e5dd7070Spatrick NonReferenceType.removeLocalConst();
3158e5dd7070Spatrick SemaRef.Diag(VD->getBeginLoc(), diag::note_use_non_reference_type)
3159e5dd7070Spatrick << NonReferenceType << VD->getSourceRange()
3160e5dd7070Spatrick << FixItHint::CreateRemoval(VD->getTypeSpecEndLoc());
3161e5dd7070Spatrick }
3162e5dd7070Spatrick }
3163e5dd7070Spatrick
3164e5dd7070Spatrick /// Determines whether the @p VariableType's declaration is a record with the
3165e5dd7070Spatrick /// clang::trivial_abi attribute.
hasTrivialABIAttr(QualType VariableType)3166e5dd7070Spatrick static bool hasTrivialABIAttr(QualType VariableType) {
3167e5dd7070Spatrick if (CXXRecordDecl *RD = VariableType->getAsCXXRecordDecl())
3168e5dd7070Spatrick return RD->hasAttr<TrivialABIAttr>();
3169e5dd7070Spatrick
3170e5dd7070Spatrick return false;
3171e5dd7070Spatrick }
3172e5dd7070Spatrick
3173e5dd7070Spatrick // Warns when the loop variable can be changed to a reference type to
3174e5dd7070Spatrick // prevent a copy. For instance, if given "for (const Foo x : Range)" suggest
3175e5dd7070Spatrick // "for (const Foo &x : Range)" if this form does not make a copy.
DiagnoseForRangeConstVariableCopies(Sema & SemaRef,const VarDecl * VD)3176e5dd7070Spatrick static void DiagnoseForRangeConstVariableCopies(Sema &SemaRef,
3177e5dd7070Spatrick const VarDecl *VD) {
3178e5dd7070Spatrick const Expr *InitExpr = VD->getInit();
3179e5dd7070Spatrick if (!InitExpr)
3180e5dd7070Spatrick return;
3181e5dd7070Spatrick
3182e5dd7070Spatrick QualType VariableType = VD->getType();
3183e5dd7070Spatrick
3184e5dd7070Spatrick if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(InitExpr)) {
3185e5dd7070Spatrick if (!CE->getConstructor()->isCopyConstructor())
3186e5dd7070Spatrick return;
3187e5dd7070Spatrick } else if (const CastExpr *CE = dyn_cast<CastExpr>(InitExpr)) {
3188e5dd7070Spatrick if (CE->getCastKind() != CK_LValueToRValue)
3189e5dd7070Spatrick return;
3190e5dd7070Spatrick } else {
3191e5dd7070Spatrick return;
3192e5dd7070Spatrick }
3193e5dd7070Spatrick
3194e5dd7070Spatrick // Small trivially copyable types are cheap to copy. Do not emit the
3195e5dd7070Spatrick // diagnostic for these instances. 64 bytes is a common size of a cache line.
3196e5dd7070Spatrick // (The function `getTypeSize` returns the size in bits.)
3197e5dd7070Spatrick ASTContext &Ctx = SemaRef.Context;
3198e5dd7070Spatrick if (Ctx.getTypeSize(VariableType) <= 64 * 8 &&
3199e5dd7070Spatrick (VariableType.isTriviallyCopyableType(Ctx) ||
3200e5dd7070Spatrick hasTrivialABIAttr(VariableType)))
3201e5dd7070Spatrick return;
3202e5dd7070Spatrick
3203e5dd7070Spatrick // Suggest changing from a const variable to a const reference variable
3204e5dd7070Spatrick // if doing so will prevent a copy.
3205e5dd7070Spatrick SemaRef.Diag(VD->getLocation(), diag::warn_for_range_copy)
3206ec727ea7Spatrick << VD << VariableType;
3207e5dd7070Spatrick SemaRef.Diag(VD->getBeginLoc(), diag::note_use_reference_type)
3208e5dd7070Spatrick << SemaRef.Context.getLValueReferenceType(VariableType)
3209e5dd7070Spatrick << VD->getSourceRange()
3210e5dd7070Spatrick << FixItHint::CreateInsertion(VD->getLocation(), "&");
3211e5dd7070Spatrick }
3212e5dd7070Spatrick
3213e5dd7070Spatrick /// DiagnoseForRangeVariableCopies - Diagnose three cases and fixes for them.
3214e5dd7070Spatrick /// 1) for (const foo &x : foos) where foos only returns a copy. Suggest
3215e5dd7070Spatrick /// using "const foo x" to show that a copy is made
3216e5dd7070Spatrick /// 2) for (const bar &x : foos) where bar is a temporary initialized by bar.
3217e5dd7070Spatrick /// Suggest either "const bar x" to keep the copying or "const foo& x" to
3218e5dd7070Spatrick /// prevent the copy.
3219e5dd7070Spatrick /// 3) for (const foo x : foos) where x is constructed from a reference foo.
3220e5dd7070Spatrick /// Suggest "const foo &x" to prevent the copy.
DiagnoseForRangeVariableCopies(Sema & SemaRef,const CXXForRangeStmt * ForStmt)3221e5dd7070Spatrick static void DiagnoseForRangeVariableCopies(Sema &SemaRef,
3222e5dd7070Spatrick const CXXForRangeStmt *ForStmt) {
3223e5dd7070Spatrick if (SemaRef.inTemplateInstantiation())
3224e5dd7070Spatrick return;
3225e5dd7070Spatrick
3226ec727ea7Spatrick if (SemaRef.Diags.isIgnored(
3227ec727ea7Spatrick diag::warn_for_range_const_ref_binds_temp_built_from_ref,
3228e5dd7070Spatrick ForStmt->getBeginLoc()) &&
3229ec727ea7Spatrick SemaRef.Diags.isIgnored(diag::warn_for_range_ref_binds_ret_temp,
3230e5dd7070Spatrick ForStmt->getBeginLoc()) &&
3231e5dd7070Spatrick SemaRef.Diags.isIgnored(diag::warn_for_range_copy,
3232e5dd7070Spatrick ForStmt->getBeginLoc())) {
3233e5dd7070Spatrick return;
3234e5dd7070Spatrick }
3235e5dd7070Spatrick
3236e5dd7070Spatrick const VarDecl *VD = ForStmt->getLoopVariable();
3237e5dd7070Spatrick if (!VD)
3238e5dd7070Spatrick return;
3239e5dd7070Spatrick
3240e5dd7070Spatrick QualType VariableType = VD->getType();
3241e5dd7070Spatrick
3242e5dd7070Spatrick if (VariableType->isIncompleteType())
3243e5dd7070Spatrick return;
3244e5dd7070Spatrick
3245e5dd7070Spatrick const Expr *InitExpr = VD->getInit();
3246e5dd7070Spatrick if (!InitExpr)
3247e5dd7070Spatrick return;
3248e5dd7070Spatrick
3249e5dd7070Spatrick if (InitExpr->getExprLoc().isMacroID())
3250e5dd7070Spatrick return;
3251e5dd7070Spatrick
3252e5dd7070Spatrick if (VariableType->isReferenceType()) {
3253e5dd7070Spatrick DiagnoseForRangeReferenceVariableCopies(SemaRef, VD,
3254e5dd7070Spatrick ForStmt->getRangeInit()->getType());
3255e5dd7070Spatrick } else if (VariableType.isConstQualified()) {
3256e5dd7070Spatrick DiagnoseForRangeConstVariableCopies(SemaRef, VD);
3257e5dd7070Spatrick }
3258e5dd7070Spatrick }
3259e5dd7070Spatrick
3260e5dd7070Spatrick /// FinishCXXForRangeStmt - Attach the body to a C++0x for-range statement.
3261e5dd7070Spatrick /// This is a separate step from ActOnCXXForRangeStmt because analysis of the
3262e5dd7070Spatrick /// body cannot be performed until after the type of the range variable is
3263e5dd7070Spatrick /// determined.
FinishCXXForRangeStmt(Stmt * S,Stmt * B)3264e5dd7070Spatrick StmtResult Sema::FinishCXXForRangeStmt(Stmt *S, Stmt *B) {
3265e5dd7070Spatrick if (!S || !B)
3266e5dd7070Spatrick return StmtError();
3267e5dd7070Spatrick
3268e5dd7070Spatrick if (isa<ObjCForCollectionStmt>(S))
3269e5dd7070Spatrick return FinishObjCForCollectionStmt(S, B);
3270e5dd7070Spatrick
3271e5dd7070Spatrick CXXForRangeStmt *ForStmt = cast<CXXForRangeStmt>(S);
3272e5dd7070Spatrick ForStmt->setBody(B);
3273e5dd7070Spatrick
3274e5dd7070Spatrick DiagnoseEmptyStmtBody(ForStmt->getRParenLoc(), B,
3275e5dd7070Spatrick diag::warn_empty_range_based_for_body);
3276e5dd7070Spatrick
3277e5dd7070Spatrick DiagnoseForRangeVariableCopies(*this, ForStmt);
3278e5dd7070Spatrick
3279e5dd7070Spatrick return S;
3280e5dd7070Spatrick }
3281e5dd7070Spatrick
ActOnGotoStmt(SourceLocation GotoLoc,SourceLocation LabelLoc,LabelDecl * TheDecl)3282e5dd7070Spatrick StmtResult Sema::ActOnGotoStmt(SourceLocation GotoLoc,
3283e5dd7070Spatrick SourceLocation LabelLoc,
3284e5dd7070Spatrick LabelDecl *TheDecl) {
3285e5dd7070Spatrick setFunctionHasBranchIntoScope();
3286e5dd7070Spatrick TheDecl->markUsed(Context);
3287e5dd7070Spatrick return new (Context) GotoStmt(TheDecl, GotoLoc, LabelLoc);
3288e5dd7070Spatrick }
3289e5dd7070Spatrick
3290e5dd7070Spatrick StmtResult
ActOnIndirectGotoStmt(SourceLocation GotoLoc,SourceLocation StarLoc,Expr * E)3291e5dd7070Spatrick Sema::ActOnIndirectGotoStmt(SourceLocation GotoLoc, SourceLocation StarLoc,
3292e5dd7070Spatrick Expr *E) {
3293e5dd7070Spatrick // Convert operand to void*
3294e5dd7070Spatrick if (!E->isTypeDependent()) {
3295e5dd7070Spatrick QualType ETy = E->getType();
3296e5dd7070Spatrick QualType DestTy = Context.getPointerType(Context.VoidTy.withConst());
3297e5dd7070Spatrick ExprResult ExprRes = E;
3298e5dd7070Spatrick AssignConvertType ConvTy =
3299e5dd7070Spatrick CheckSingleAssignmentConstraints(DestTy, ExprRes);
3300e5dd7070Spatrick if (ExprRes.isInvalid())
3301e5dd7070Spatrick return StmtError();
3302e5dd7070Spatrick E = ExprRes.get();
3303e5dd7070Spatrick if (DiagnoseAssignmentResult(ConvTy, StarLoc, DestTy, ETy, E, AA_Passing))
3304e5dd7070Spatrick return StmtError();
3305e5dd7070Spatrick }
3306e5dd7070Spatrick
3307e5dd7070Spatrick ExprResult ExprRes = ActOnFinishFullExpr(E, /*DiscardedValue*/ false);
3308e5dd7070Spatrick if (ExprRes.isInvalid())
3309e5dd7070Spatrick return StmtError();
3310e5dd7070Spatrick E = ExprRes.get();
3311e5dd7070Spatrick
3312e5dd7070Spatrick setFunctionHasIndirectGoto();
3313e5dd7070Spatrick
3314e5dd7070Spatrick return new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E);
3315e5dd7070Spatrick }
3316e5dd7070Spatrick
CheckJumpOutOfSEHFinally(Sema & S,SourceLocation Loc,const Scope & DestScope)3317e5dd7070Spatrick static void CheckJumpOutOfSEHFinally(Sema &S, SourceLocation Loc,
3318e5dd7070Spatrick const Scope &DestScope) {
3319e5dd7070Spatrick if (!S.CurrentSEHFinally.empty() &&
3320e5dd7070Spatrick DestScope.Contains(*S.CurrentSEHFinally.back())) {
3321e5dd7070Spatrick S.Diag(Loc, diag::warn_jump_out_of_seh_finally);
3322e5dd7070Spatrick }
3323e5dd7070Spatrick }
3324e5dd7070Spatrick
3325e5dd7070Spatrick StmtResult
ActOnContinueStmt(SourceLocation ContinueLoc,Scope * CurScope)3326e5dd7070Spatrick Sema::ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope) {
3327e5dd7070Spatrick Scope *S = CurScope->getContinueParent();
3328e5dd7070Spatrick if (!S) {
3329e5dd7070Spatrick // C99 6.8.6.2p1: A break shall appear only in or as a loop body.
3330e5dd7070Spatrick return StmtError(Diag(ContinueLoc, diag::err_continue_not_in_loop));
3331e5dd7070Spatrick }
3332*12c85518Srobert if (S->isConditionVarScope()) {
3333a9ac8606Spatrick // We cannot 'continue;' from within a statement expression in the
3334a9ac8606Spatrick // initializer of a condition variable because we would jump past the
3335a9ac8606Spatrick // initialization of that variable.
3336a9ac8606Spatrick return StmtError(Diag(ContinueLoc, diag::err_continue_from_cond_var_init));
3337a9ac8606Spatrick }
3338e5dd7070Spatrick CheckJumpOutOfSEHFinally(*this, ContinueLoc, *S);
3339e5dd7070Spatrick
3340e5dd7070Spatrick return new (Context) ContinueStmt(ContinueLoc);
3341e5dd7070Spatrick }
3342e5dd7070Spatrick
3343e5dd7070Spatrick StmtResult
ActOnBreakStmt(SourceLocation BreakLoc,Scope * CurScope)3344e5dd7070Spatrick Sema::ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope) {
3345e5dd7070Spatrick Scope *S = CurScope->getBreakParent();
3346e5dd7070Spatrick if (!S) {
3347e5dd7070Spatrick // C99 6.8.6.3p1: A break shall appear only in or as a switch/loop body.
3348e5dd7070Spatrick return StmtError(Diag(BreakLoc, diag::err_break_not_in_loop_or_switch));
3349e5dd7070Spatrick }
3350e5dd7070Spatrick if (S->isOpenMPLoopScope())
3351e5dd7070Spatrick return StmtError(Diag(BreakLoc, diag::err_omp_loop_cannot_use_stmt)
3352e5dd7070Spatrick << "break");
3353e5dd7070Spatrick CheckJumpOutOfSEHFinally(*this, BreakLoc, *S);
3354e5dd7070Spatrick
3355e5dd7070Spatrick return new (Context) BreakStmt(BreakLoc);
3356e5dd7070Spatrick }
3357e5dd7070Spatrick
3358a9ac8606Spatrick /// Determine whether the given expression might be move-eligible or
3359a9ac8606Spatrick /// copy-elidable in either a (co_)return statement or throw expression,
3360a9ac8606Spatrick /// without considering function return type, if applicable.
3361e5dd7070Spatrick ///
3362a9ac8606Spatrick /// \param E The expression being returned from the function or block,
3363a9ac8606Spatrick /// being thrown, or being co_returned from a coroutine. This expression
3364a9ac8606Spatrick /// might be modified by the implementation.
3365e5dd7070Spatrick ///
3366*12c85518Srobert /// \param Mode Overrides detection of current language mode
3367a9ac8606Spatrick /// and uses the rules for C++2b.
3368e5dd7070Spatrick ///
3369a9ac8606Spatrick /// \returns An aggregate which contains the Candidate and isMoveEligible
3370a9ac8606Spatrick /// and isCopyElidable methods. If Candidate is non-null, it means
3371a9ac8606Spatrick /// isMoveEligible() would be true under the most permissive language standard.
getNamedReturnInfo(Expr * & E,SimplerImplicitMoveMode Mode)3372a9ac8606Spatrick Sema::NamedReturnInfo Sema::getNamedReturnInfo(Expr *&E,
3373a9ac8606Spatrick SimplerImplicitMoveMode Mode) {
3374a9ac8606Spatrick if (!E)
3375a9ac8606Spatrick return NamedReturnInfo();
3376e5dd7070Spatrick // - in a return statement in a function [where] ...
3377e5dd7070Spatrick // ... the expression is the name of a non-volatile automatic object ...
3378a9ac8606Spatrick const auto *DR = dyn_cast<DeclRefExpr>(E->IgnoreParens());
3379e5dd7070Spatrick if (!DR || DR->refersToEnclosingVariableOrCapture())
3380a9ac8606Spatrick return NamedReturnInfo();
3381a9ac8606Spatrick const auto *VD = dyn_cast<VarDecl>(DR->getDecl());
3382e5dd7070Spatrick if (!VD)
3383a9ac8606Spatrick return NamedReturnInfo();
3384a9ac8606Spatrick NamedReturnInfo Res = getNamedReturnInfo(VD);
3385a9ac8606Spatrick if (Res.Candidate && !E->isXValue() &&
3386a9ac8606Spatrick (Mode == SimplerImplicitMoveMode::ForceOn ||
3387a9ac8606Spatrick (Mode != SimplerImplicitMoveMode::ForceOff &&
3388a9ac8606Spatrick getLangOpts().CPlusPlus2b))) {
3389a9ac8606Spatrick E = ImplicitCastExpr::Create(Context, VD->getType().getNonReferenceType(),
3390a9ac8606Spatrick CK_NoOp, E, nullptr, VK_XValue,
3391a9ac8606Spatrick FPOptionsOverride());
3392a9ac8606Spatrick }
3393a9ac8606Spatrick return Res;
3394e5dd7070Spatrick }
3395e5dd7070Spatrick
3396a9ac8606Spatrick /// Determine whether the given NRVO candidate variable is move-eligible or
3397a9ac8606Spatrick /// copy-elidable, without considering function return type.
3398a9ac8606Spatrick ///
3399a9ac8606Spatrick /// \param VD The NRVO candidate variable.
3400a9ac8606Spatrick ///
3401a9ac8606Spatrick /// \returns An aggregate which contains the Candidate and isMoveEligible
3402a9ac8606Spatrick /// and isCopyElidable methods. If Candidate is non-null, it means
3403a9ac8606Spatrick /// isMoveEligible() would be true under the most permissive language standard.
getNamedReturnInfo(const VarDecl * VD)3404a9ac8606Spatrick Sema::NamedReturnInfo Sema::getNamedReturnInfo(const VarDecl *VD) {
3405a9ac8606Spatrick NamedReturnInfo Info{VD, NamedReturnInfo::MoveEligibleAndCopyElidable};
3406a9ac8606Spatrick
3407a9ac8606Spatrick // C++20 [class.copy.elision]p3:
3408e5dd7070Spatrick // - in a return statement in a function with ...
3409a9ac8606Spatrick // (other than a function ... parameter)
3410a9ac8606Spatrick if (VD->getKind() == Decl::ParmVar)
3411a9ac8606Spatrick Info.S = NamedReturnInfo::MoveEligible;
3412a9ac8606Spatrick else if (VD->getKind() != Decl::Var)
3413a9ac8606Spatrick return NamedReturnInfo();
3414e5dd7070Spatrick
3415a9ac8606Spatrick // (other than ... a catch-clause parameter)
3416a9ac8606Spatrick if (VD->isExceptionVariable())
3417a9ac8606Spatrick Info.S = NamedReturnInfo::MoveEligible;
3418e5dd7070Spatrick
3419e5dd7070Spatrick // ...automatic...
3420a9ac8606Spatrick if (!VD->hasLocalStorage())
3421a9ac8606Spatrick return NamedReturnInfo();
3422e5dd7070Spatrick
3423a9ac8606Spatrick // We don't want to implicitly move out of a __block variable during a return
3424a9ac8606Spatrick // because we cannot assume the variable will no longer be used.
3425a9ac8606Spatrick if (VD->hasAttr<BlocksAttr>())
3426a9ac8606Spatrick return NamedReturnInfo();
3427e5dd7070Spatrick
3428a9ac8606Spatrick QualType VDType = VD->getType();
3429a9ac8606Spatrick if (VDType->isObjectType()) {
3430a9ac8606Spatrick // C++17 [class.copy.elision]p3:
3431a9ac8606Spatrick // ...non-volatile automatic object...
3432a9ac8606Spatrick if (VDType.isVolatileQualified())
3433a9ac8606Spatrick return NamedReturnInfo();
3434a9ac8606Spatrick } else if (VDType->isRValueReferenceType()) {
3435a9ac8606Spatrick // C++20 [class.copy.elision]p3:
3436a9ac8606Spatrick // ...either a non-volatile object or an rvalue reference to a non-volatile
3437a9ac8606Spatrick // object type...
3438a9ac8606Spatrick QualType VDReferencedType = VDType.getNonReferenceType();
3439a9ac8606Spatrick if (VDReferencedType.isVolatileQualified() ||
3440a9ac8606Spatrick !VDReferencedType->isObjectType())
3441a9ac8606Spatrick return NamedReturnInfo();
3442a9ac8606Spatrick Info.S = NamedReturnInfo::MoveEligible;
3443a9ac8606Spatrick } else {
3444a9ac8606Spatrick return NamedReturnInfo();
3445a9ac8606Spatrick }
3446e5dd7070Spatrick
3447e5dd7070Spatrick // Variables with higher required alignment than their type's ABI
3448e5dd7070Spatrick // alignment cannot use NRVO.
3449a9ac8606Spatrick if (!VD->hasDependentAlignment() &&
3450a9ac8606Spatrick Context.getDeclAlign(VD) > Context.getTypeAlignInChars(VDType))
3451a9ac8606Spatrick Info.S = NamedReturnInfo::MoveEligible;
3452a9ac8606Spatrick
3453a9ac8606Spatrick return Info;
3454a9ac8606Spatrick }
3455a9ac8606Spatrick
3456a9ac8606Spatrick /// Updates given NamedReturnInfo's move-eligible and
3457a9ac8606Spatrick /// copy-elidable statuses, considering the function
3458a9ac8606Spatrick /// return type criteria as applicable to return statements.
3459a9ac8606Spatrick ///
3460a9ac8606Spatrick /// \param Info The NamedReturnInfo object to update.
3461a9ac8606Spatrick ///
3462a9ac8606Spatrick /// \param ReturnType This is the return type of the function.
3463a9ac8606Spatrick /// \returns The copy elision candidate, in case the initial return expression
3464a9ac8606Spatrick /// was copy elidable, or nullptr otherwise.
getCopyElisionCandidate(NamedReturnInfo & Info,QualType ReturnType)3465a9ac8606Spatrick const VarDecl *Sema::getCopyElisionCandidate(NamedReturnInfo &Info,
3466a9ac8606Spatrick QualType ReturnType) {
3467a9ac8606Spatrick if (!Info.Candidate)
3468a9ac8606Spatrick return nullptr;
3469a9ac8606Spatrick
3470a9ac8606Spatrick auto invalidNRVO = [&] {
3471a9ac8606Spatrick Info = NamedReturnInfo();
3472a9ac8606Spatrick return nullptr;
3473a9ac8606Spatrick };
3474a9ac8606Spatrick
3475a9ac8606Spatrick // If we got a non-deduced auto ReturnType, we are in a dependent context and
3476a9ac8606Spatrick // there is no point in allowing copy elision since we won't have it deduced
3477a9ac8606Spatrick // by the point the VardDecl is instantiated, which is the last chance we have
3478a9ac8606Spatrick // of deciding if the candidate is really copy elidable.
3479a9ac8606Spatrick if ((ReturnType->getTypeClass() == Type::TypeClass::Auto &&
3480a9ac8606Spatrick ReturnType->isCanonicalUnqualified()) ||
3481a9ac8606Spatrick ReturnType->isSpecificBuiltinType(BuiltinType::Dependent))
3482a9ac8606Spatrick return invalidNRVO();
3483a9ac8606Spatrick
3484a9ac8606Spatrick if (!ReturnType->isDependentType()) {
3485a9ac8606Spatrick // - in a return statement in a function with ...
3486a9ac8606Spatrick // ... a class return type ...
3487a9ac8606Spatrick if (!ReturnType->isRecordType())
3488a9ac8606Spatrick return invalidNRVO();
3489a9ac8606Spatrick
3490a9ac8606Spatrick QualType VDType = Info.Candidate->getType();
3491a9ac8606Spatrick // ... the same cv-unqualified type as the function return type ...
3492a9ac8606Spatrick // When considering moving this expression out, allow dissimilar types.
3493a9ac8606Spatrick if (!VDType->isDependentType() &&
3494a9ac8606Spatrick !Context.hasSameUnqualifiedType(ReturnType, VDType))
3495a9ac8606Spatrick Info.S = NamedReturnInfo::MoveEligible;
3496a9ac8606Spatrick }
3497a9ac8606Spatrick return Info.isCopyElidable() ? Info.Candidate : nullptr;
3498a9ac8606Spatrick }
3499a9ac8606Spatrick
3500a9ac8606Spatrick /// Verify that the initialization sequence that was picked for the
3501a9ac8606Spatrick /// first overload resolution is permissible under C++98.
3502a9ac8606Spatrick ///
3503*12c85518Srobert /// Reject (possibly converting) constructors not taking an rvalue reference,
3504a9ac8606Spatrick /// or user conversion operators which are not ref-qualified.
3505a9ac8606Spatrick static bool
VerifyInitializationSequenceCXX98(const Sema & S,const InitializationSequence & Seq)3506a9ac8606Spatrick VerifyInitializationSequenceCXX98(const Sema &S,
3507a9ac8606Spatrick const InitializationSequence &Seq) {
3508a9ac8606Spatrick const auto *Step = llvm::find_if(Seq.steps(), [](const auto &Step) {
3509a9ac8606Spatrick return Step.Kind == InitializationSequence::SK_ConstructorInitialization ||
3510a9ac8606Spatrick Step.Kind == InitializationSequence::SK_UserConversion;
3511a9ac8606Spatrick });
3512a9ac8606Spatrick if (Step != Seq.step_end()) {
3513a9ac8606Spatrick const auto *FD = Step->Function.Function;
3514a9ac8606Spatrick if (isa<CXXConstructorDecl>(FD)
3515a9ac8606Spatrick ? !FD->getParamDecl(0)->getType()->isRValueReferenceType()
3516a9ac8606Spatrick : cast<CXXMethodDecl>(FD)->getRefQualifier() == RQ_None)
3517e5dd7070Spatrick return false;
3518a9ac8606Spatrick }
3519e5dd7070Spatrick return true;
3520e5dd7070Spatrick }
3521e5dd7070Spatrick
3522e5dd7070Spatrick /// Perform the initialization of a potentially-movable value, which
3523e5dd7070Spatrick /// is the result of return value.
3524e5dd7070Spatrick ///
3525a9ac8606Spatrick /// This routine implements C++20 [class.copy.elision]p3, which attempts to
3526a9ac8606Spatrick /// treat returned lvalues as rvalues in certain cases (to prefer move
3527a9ac8606Spatrick /// construction), then falls back to treating them as lvalues if that failed.
PerformMoveOrCopyInitialization(const InitializedEntity & Entity,const NamedReturnInfo & NRInfo,Expr * Value,bool SupressSimplerImplicitMoves)3528a9ac8606Spatrick ExprResult Sema::PerformMoveOrCopyInitialization(
3529a9ac8606Spatrick const InitializedEntity &Entity, const NamedReturnInfo &NRInfo, Expr *Value,
3530a9ac8606Spatrick bool SupressSimplerImplicitMoves) {
3531a9ac8606Spatrick if (getLangOpts().CPlusPlus &&
3532a9ac8606Spatrick (!getLangOpts().CPlusPlus2b || SupressSimplerImplicitMoves) &&
3533a9ac8606Spatrick NRInfo.isMoveEligible()) {
3534a9ac8606Spatrick ImplicitCastExpr AsRvalue(ImplicitCastExpr::OnStack, Value->getType(),
3535a9ac8606Spatrick CK_NoOp, Value, VK_XValue, FPOptionsOverride());
3536a9ac8606Spatrick Expr *InitExpr = &AsRvalue;
3537a9ac8606Spatrick auto Kind = InitializationKind::CreateCopy(Value->getBeginLoc(),
3538a9ac8606Spatrick Value->getBeginLoc());
3539a9ac8606Spatrick InitializationSequence Seq(*this, Entity, Kind, InitExpr);
3540a9ac8606Spatrick auto Res = Seq.getFailedOverloadResult();
3541a9ac8606Spatrick if ((Res == OR_Success || Res == OR_Deleted) &&
3542a9ac8606Spatrick (getLangOpts().CPlusPlus11 ||
3543a9ac8606Spatrick VerifyInitializationSequenceCXX98(*this, Seq))) {
3544a9ac8606Spatrick // Promote "AsRvalue" to the heap, since we now need this
3545a9ac8606Spatrick // expression node to persist.
3546a9ac8606Spatrick Value =
3547a9ac8606Spatrick ImplicitCastExpr::Create(Context, Value->getType(), CK_NoOp, Value,
3548a9ac8606Spatrick nullptr, VK_XValue, FPOptionsOverride());
3549a9ac8606Spatrick // Complete type-checking the initialization of the return type
3550a9ac8606Spatrick // using the constructor we found.
3551a9ac8606Spatrick return Seq.Perform(*this, Entity, Kind, Value);
3552e5dd7070Spatrick }
3553e5dd7070Spatrick }
3554e5dd7070Spatrick // Either we didn't meet the criteria for treating an lvalue as an rvalue,
3555e5dd7070Spatrick // above, or overload resolution failed. Either way, we need to try
3556e5dd7070Spatrick // (again) now with the return value expression as written.
3557a9ac8606Spatrick return PerformCopyInitialization(Entity, SourceLocation(), Value);
3558e5dd7070Spatrick }
3559e5dd7070Spatrick
3560e5dd7070Spatrick /// Determine whether the declared return type of the specified function
3561e5dd7070Spatrick /// contains 'auto'.
hasDeducedReturnType(FunctionDecl * FD)3562e5dd7070Spatrick static bool hasDeducedReturnType(FunctionDecl *FD) {
3563e5dd7070Spatrick const FunctionProtoType *FPT =
3564e5dd7070Spatrick FD->getTypeSourceInfo()->getType()->castAs<FunctionProtoType>();
3565e5dd7070Spatrick return FPT->getReturnType()->isUndeducedType();
3566e5dd7070Spatrick }
3567e5dd7070Spatrick
3568e5dd7070Spatrick /// ActOnCapScopeReturnStmt - Utility routine to type-check return statements
3569e5dd7070Spatrick /// for capturing scopes.
3570e5dd7070Spatrick ///
ActOnCapScopeReturnStmt(SourceLocation ReturnLoc,Expr * RetValExp,NamedReturnInfo & NRInfo,bool SupressSimplerImplicitMoves)3571a9ac8606Spatrick StmtResult Sema::ActOnCapScopeReturnStmt(SourceLocation ReturnLoc,
3572a9ac8606Spatrick Expr *RetValExp,
3573a9ac8606Spatrick NamedReturnInfo &NRInfo,
3574a9ac8606Spatrick bool SupressSimplerImplicitMoves) {
3575e5dd7070Spatrick // If this is the first return we've seen, infer the return type.
3576e5dd7070Spatrick // [expr.prim.lambda]p4 in C++11; block literals follow the same rules.
3577e5dd7070Spatrick CapturingScopeInfo *CurCap = cast<CapturingScopeInfo>(getCurFunction());
3578e5dd7070Spatrick QualType FnRetType = CurCap->ReturnType;
3579e5dd7070Spatrick LambdaScopeInfo *CurLambda = dyn_cast<LambdaScopeInfo>(CurCap);
3580e5dd7070Spatrick bool HasDeducedReturnType =
3581e5dd7070Spatrick CurLambda && hasDeducedReturnType(CurLambda->CallOperator);
3582e5dd7070Spatrick
3583*12c85518Srobert if (ExprEvalContexts.back().isDiscardedStatementContext() &&
3584e5dd7070Spatrick (HasDeducedReturnType || CurCap->HasImplicitReturnType)) {
3585e5dd7070Spatrick if (RetValExp) {
3586e5dd7070Spatrick ExprResult ER =
3587e5dd7070Spatrick ActOnFinishFullExpr(RetValExp, ReturnLoc, /*DiscardedValue*/ false);
3588e5dd7070Spatrick if (ER.isInvalid())
3589e5dd7070Spatrick return StmtError();
3590e5dd7070Spatrick RetValExp = ER.get();
3591e5dd7070Spatrick }
3592e5dd7070Spatrick return ReturnStmt::Create(Context, ReturnLoc, RetValExp,
3593e5dd7070Spatrick /* NRVOCandidate=*/nullptr);
3594e5dd7070Spatrick }
3595e5dd7070Spatrick
3596e5dd7070Spatrick if (HasDeducedReturnType) {
3597a9ac8606Spatrick FunctionDecl *FD = CurLambda->CallOperator;
3598a9ac8606Spatrick // If we've already decided this lambda is invalid, e.g. because
3599a9ac8606Spatrick // we saw a `return` whose expression had an error, don't keep
3600a9ac8606Spatrick // trying to deduce its return type.
3601a9ac8606Spatrick if (FD->isInvalidDecl())
3602a9ac8606Spatrick return StmtError();
3603e5dd7070Spatrick // In C++1y, the return type may involve 'auto'.
3604e5dd7070Spatrick // FIXME: Blocks might have a return type of 'auto' explicitly specified.
3605e5dd7070Spatrick if (CurCap->ReturnType.isNull())
3606e5dd7070Spatrick CurCap->ReturnType = FD->getReturnType();
3607e5dd7070Spatrick
3608e5dd7070Spatrick AutoType *AT = CurCap->ReturnType->getContainedAutoType();
3609e5dd7070Spatrick assert(AT && "lost auto type from lambda return type");
3610e5dd7070Spatrick if (DeduceFunctionTypeFromReturnExpr(FD, ReturnLoc, RetValExp, AT)) {
3611e5dd7070Spatrick FD->setInvalidDecl();
3612ec727ea7Spatrick // FIXME: preserve the ill-formed return expression.
3613e5dd7070Spatrick return StmtError();
3614e5dd7070Spatrick }
3615e5dd7070Spatrick CurCap->ReturnType = FnRetType = FD->getReturnType();
3616e5dd7070Spatrick } else if (CurCap->HasImplicitReturnType) {
3617e5dd7070Spatrick // For blocks/lambdas with implicit return types, we check each return
3618e5dd7070Spatrick // statement individually, and deduce the common return type when the block
3619e5dd7070Spatrick // or lambda is completed.
3620e5dd7070Spatrick // FIXME: Fold this into the 'auto' codepath above.
3621e5dd7070Spatrick if (RetValExp && !isa<InitListExpr>(RetValExp)) {
3622e5dd7070Spatrick ExprResult Result = DefaultFunctionArrayLvalueConversion(RetValExp);
3623e5dd7070Spatrick if (Result.isInvalid())
3624e5dd7070Spatrick return StmtError();
3625e5dd7070Spatrick RetValExp = Result.get();
3626e5dd7070Spatrick
3627e5dd7070Spatrick // DR1048: even prior to C++14, we should use the 'auto' deduction rules
3628e5dd7070Spatrick // when deducing a return type for a lambda-expression (or by extension
3629e5dd7070Spatrick // for a block). These rules differ from the stated C++11 rules only in
3630e5dd7070Spatrick // that they remove top-level cv-qualifiers.
3631e5dd7070Spatrick if (!CurContext->isDependentContext())
3632e5dd7070Spatrick FnRetType = RetValExp->getType().getUnqualifiedType();
3633e5dd7070Spatrick else
3634e5dd7070Spatrick FnRetType = CurCap->ReturnType = Context.DependentTy;
3635e5dd7070Spatrick } else {
3636e5dd7070Spatrick if (RetValExp) {
3637e5dd7070Spatrick // C++11 [expr.lambda.prim]p4 bans inferring the result from an
3638e5dd7070Spatrick // initializer list, because it is not an expression (even
3639e5dd7070Spatrick // though we represent it as one). We still deduce 'void'.
3640e5dd7070Spatrick Diag(ReturnLoc, diag::err_lambda_return_init_list)
3641e5dd7070Spatrick << RetValExp->getSourceRange();
3642e5dd7070Spatrick }
3643e5dd7070Spatrick
3644e5dd7070Spatrick FnRetType = Context.VoidTy;
3645e5dd7070Spatrick }
3646e5dd7070Spatrick
3647e5dd7070Spatrick // Although we'll properly infer the type of the block once it's completed,
3648e5dd7070Spatrick // make sure we provide a return type now for better error recovery.
3649e5dd7070Spatrick if (CurCap->ReturnType.isNull())
3650e5dd7070Spatrick CurCap->ReturnType = FnRetType;
3651e5dd7070Spatrick }
3652a9ac8606Spatrick const VarDecl *NRVOCandidate = getCopyElisionCandidate(NRInfo, FnRetType);
3653e5dd7070Spatrick
3654e5dd7070Spatrick if (auto *CurBlock = dyn_cast<BlockScopeInfo>(CurCap)) {
3655e5dd7070Spatrick if (CurBlock->FunctionType->castAs<FunctionType>()->getNoReturnAttr()) {
3656e5dd7070Spatrick Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr);
3657e5dd7070Spatrick return StmtError();
3658e5dd7070Spatrick }
3659e5dd7070Spatrick } else if (auto *CurRegion = dyn_cast<CapturedRegionScopeInfo>(CurCap)) {
3660e5dd7070Spatrick Diag(ReturnLoc, diag::err_return_in_captured_stmt) << CurRegion->getRegionName();
3661e5dd7070Spatrick return StmtError();
3662e5dd7070Spatrick } else {
3663e5dd7070Spatrick assert(CurLambda && "unknown kind of captured scope");
3664e5dd7070Spatrick if (CurLambda->CallOperator->getType()
3665e5dd7070Spatrick ->castAs<FunctionType>()
3666e5dd7070Spatrick ->getNoReturnAttr()) {
3667e5dd7070Spatrick Diag(ReturnLoc, diag::err_noreturn_lambda_has_return_expr);
3668e5dd7070Spatrick return StmtError();
3669e5dd7070Spatrick }
3670e5dd7070Spatrick }
3671e5dd7070Spatrick
3672e5dd7070Spatrick // Otherwise, verify that this result type matches the previous one. We are
3673e5dd7070Spatrick // pickier with blocks than for normal functions because we don't have GCC
3674e5dd7070Spatrick // compatibility to worry about here.
3675e5dd7070Spatrick if (FnRetType->isDependentType()) {
3676e5dd7070Spatrick // Delay processing for now. TODO: there are lots of dependent
3677e5dd7070Spatrick // types we can conclusively prove aren't void.
3678e5dd7070Spatrick } else if (FnRetType->isVoidType()) {
3679e5dd7070Spatrick if (RetValExp && !isa<InitListExpr>(RetValExp) &&
3680e5dd7070Spatrick !(getLangOpts().CPlusPlus &&
3681e5dd7070Spatrick (RetValExp->isTypeDependent() ||
3682e5dd7070Spatrick RetValExp->getType()->isVoidType()))) {
3683e5dd7070Spatrick if (!getLangOpts().CPlusPlus &&
3684e5dd7070Spatrick RetValExp->getType()->isVoidType())
3685e5dd7070Spatrick Diag(ReturnLoc, diag::ext_return_has_void_expr) << "literal" << 2;
3686e5dd7070Spatrick else {
3687e5dd7070Spatrick Diag(ReturnLoc, diag::err_return_block_has_expr);
3688e5dd7070Spatrick RetValExp = nullptr;
3689e5dd7070Spatrick }
3690e5dd7070Spatrick }
3691e5dd7070Spatrick } else if (!RetValExp) {
3692e5dd7070Spatrick return StmtError(Diag(ReturnLoc, diag::err_block_return_missing_expr));
3693e5dd7070Spatrick } else if (!RetValExp->isTypeDependent()) {
3694e5dd7070Spatrick // we have a non-void block with an expression, continue checking
3695e5dd7070Spatrick
3696e5dd7070Spatrick // C99 6.8.6.4p3(136): The return statement is not an assignment. The
3697e5dd7070Spatrick // overlap restriction of subclause 6.5.16.1 does not apply to the case of
3698e5dd7070Spatrick // function return.
3699e5dd7070Spatrick
3700e5dd7070Spatrick // In C++ the return statement is handled via a copy initialization.
3701e5dd7070Spatrick // the C version of which boils down to CheckSingleAssignmentConstraints.
3702a9ac8606Spatrick InitializedEntity Entity =
3703a9ac8606Spatrick InitializedEntity::InitializeResult(ReturnLoc, FnRetType);
3704a9ac8606Spatrick ExprResult Res = PerformMoveOrCopyInitialization(
3705a9ac8606Spatrick Entity, NRInfo, RetValExp, SupressSimplerImplicitMoves);
3706e5dd7070Spatrick if (Res.isInvalid()) {
3707e5dd7070Spatrick // FIXME: Cleanup temporaries here, anyway?
3708e5dd7070Spatrick return StmtError();
3709e5dd7070Spatrick }
3710e5dd7070Spatrick RetValExp = Res.get();
3711e5dd7070Spatrick CheckReturnValExpr(RetValExp, FnRetType, ReturnLoc);
3712e5dd7070Spatrick }
3713e5dd7070Spatrick
3714e5dd7070Spatrick if (RetValExp) {
3715e5dd7070Spatrick ExprResult ER =
3716e5dd7070Spatrick ActOnFinishFullExpr(RetValExp, ReturnLoc, /*DiscardedValue*/ false);
3717e5dd7070Spatrick if (ER.isInvalid())
3718e5dd7070Spatrick return StmtError();
3719e5dd7070Spatrick RetValExp = ER.get();
3720e5dd7070Spatrick }
3721e5dd7070Spatrick auto *Result =
3722e5dd7070Spatrick ReturnStmt::Create(Context, ReturnLoc, RetValExp, NRVOCandidate);
3723e5dd7070Spatrick
3724e5dd7070Spatrick // If we need to check for the named return value optimization,
3725e5dd7070Spatrick // or if we need to infer the return type,
3726e5dd7070Spatrick // save the return statement in our scope for later processing.
3727e5dd7070Spatrick if (CurCap->HasImplicitReturnType || NRVOCandidate)
3728e5dd7070Spatrick FunctionScopes.back()->Returns.push_back(Result);
3729e5dd7070Spatrick
3730e5dd7070Spatrick if (FunctionScopes.back()->FirstReturnLoc.isInvalid())
3731e5dd7070Spatrick FunctionScopes.back()->FirstReturnLoc = ReturnLoc;
3732e5dd7070Spatrick
3733e5dd7070Spatrick return Result;
3734e5dd7070Spatrick }
3735e5dd7070Spatrick
3736e5dd7070Spatrick namespace {
3737e5dd7070Spatrick /// Marks all typedefs in all local classes in a type referenced.
3738e5dd7070Spatrick ///
3739e5dd7070Spatrick /// In a function like
3740e5dd7070Spatrick /// auto f() {
3741e5dd7070Spatrick /// struct S { typedef int a; };
3742e5dd7070Spatrick /// return S();
3743e5dd7070Spatrick /// }
3744e5dd7070Spatrick ///
3745e5dd7070Spatrick /// the local type escapes and could be referenced in some TUs but not in
3746e5dd7070Spatrick /// others. Pretend that all local typedefs are always referenced, to not warn
3747e5dd7070Spatrick /// on this. This isn't necessary if f has internal linkage, or the typedef
3748e5dd7070Spatrick /// is private.
3749e5dd7070Spatrick class LocalTypedefNameReferencer
3750e5dd7070Spatrick : public RecursiveASTVisitor<LocalTypedefNameReferencer> {
3751e5dd7070Spatrick public:
LocalTypedefNameReferencer(Sema & S)3752e5dd7070Spatrick LocalTypedefNameReferencer(Sema &S) : S(S) {}
3753e5dd7070Spatrick bool VisitRecordType(const RecordType *RT);
3754e5dd7070Spatrick private:
3755e5dd7070Spatrick Sema &S;
3756e5dd7070Spatrick };
VisitRecordType(const RecordType * RT)3757e5dd7070Spatrick bool LocalTypedefNameReferencer::VisitRecordType(const RecordType *RT) {
3758e5dd7070Spatrick auto *R = dyn_cast<CXXRecordDecl>(RT->getDecl());
3759e5dd7070Spatrick if (!R || !R->isLocalClass() || !R->isLocalClass()->isExternallyVisible() ||
3760e5dd7070Spatrick R->isDependentType())
3761e5dd7070Spatrick return true;
3762e5dd7070Spatrick for (auto *TmpD : R->decls())
3763e5dd7070Spatrick if (auto *T = dyn_cast<TypedefNameDecl>(TmpD))
3764e5dd7070Spatrick if (T->getAccess() != AS_private || R->hasFriends())
3765e5dd7070Spatrick S.MarkAnyDeclReferenced(T->getLocation(), T, /*OdrUse=*/false);
3766e5dd7070Spatrick return true;
3767e5dd7070Spatrick }
3768e5dd7070Spatrick }
3769e5dd7070Spatrick
getReturnTypeLoc(FunctionDecl * FD) const3770e5dd7070Spatrick TypeLoc Sema::getReturnTypeLoc(FunctionDecl *FD) const {
3771e5dd7070Spatrick return FD->getTypeSourceInfo()
3772e5dd7070Spatrick ->getTypeLoc()
3773e5dd7070Spatrick .getAsAdjusted<FunctionProtoTypeLoc>()
3774e5dd7070Spatrick .getReturnLoc();
3775e5dd7070Spatrick }
3776e5dd7070Spatrick
3777e5dd7070Spatrick /// Deduce the return type for a function from a returned expression, per
3778e5dd7070Spatrick /// C++1y [dcl.spec.auto]p6.
DeduceFunctionTypeFromReturnExpr(FunctionDecl * FD,SourceLocation ReturnLoc,Expr * RetExpr,const AutoType * AT)3779e5dd7070Spatrick bool Sema::DeduceFunctionTypeFromReturnExpr(FunctionDecl *FD,
3780e5dd7070Spatrick SourceLocation ReturnLoc,
3781*12c85518Srobert Expr *RetExpr, const AutoType *AT) {
3782*12c85518Srobert // If this is the conversion function for a lambda, we choose to deduce its
3783e5dd7070Spatrick // type from the corresponding call operator, not from the synthesized return
3784e5dd7070Spatrick // statement within it. See Sema::DeduceReturnType.
3785e5dd7070Spatrick if (isLambdaConversionOperator(FD))
3786e5dd7070Spatrick return false;
3787e5dd7070Spatrick
3788e5dd7070Spatrick if (RetExpr && isa<InitListExpr>(RetExpr)) {
3789e5dd7070Spatrick // If the deduction is for a return statement and the initializer is
3790e5dd7070Spatrick // a braced-init-list, the program is ill-formed.
3791e5dd7070Spatrick Diag(RetExpr->getExprLoc(),
3792e5dd7070Spatrick getCurLambda() ? diag::err_lambda_return_init_list
3793e5dd7070Spatrick : diag::err_auto_fn_return_init_list)
3794e5dd7070Spatrick << RetExpr->getSourceRange();
3795e5dd7070Spatrick return true;
3796e5dd7070Spatrick }
3797e5dd7070Spatrick
3798e5dd7070Spatrick if (FD->isDependentContext()) {
3799e5dd7070Spatrick // C++1y [dcl.spec.auto]p12:
3800e5dd7070Spatrick // Return type deduction [...] occurs when the definition is
3801e5dd7070Spatrick // instantiated even if the function body contains a return
3802e5dd7070Spatrick // statement with a non-type-dependent operand.
3803e5dd7070Spatrick assert(AT->isDeduced() && "should have deduced to dependent type");
3804e5dd7070Spatrick return false;
3805e5dd7070Spatrick }
3806e5dd7070Spatrick
3807*12c85518Srobert TypeLoc OrigResultType = getReturnTypeLoc(FD);
3808e5dd7070Spatrick // In the case of a return with no operand, the initializer is considered
3809e5dd7070Spatrick // to be void().
3810*12c85518Srobert CXXScalarValueInitExpr VoidVal(Context.VoidTy, nullptr, SourceLocation());
3811*12c85518Srobert if (!RetExpr) {
3812*12c85518Srobert // For a function with a deduced result type to return with omitted
3813*12c85518Srobert // expression, the result type as written must be 'auto' or
3814*12c85518Srobert // 'decltype(auto)', possibly cv-qualified or constrained, but not
3815*12c85518Srobert // ref-qualified.
3816e5dd7070Spatrick if (!OrigResultType.getType()->getAs<AutoType>()) {
3817e5dd7070Spatrick Diag(ReturnLoc, diag::err_auto_fn_return_void_but_not_auto)
3818e5dd7070Spatrick << OrigResultType.getType();
3819e5dd7070Spatrick return true;
3820e5dd7070Spatrick }
3821*12c85518Srobert RetExpr = &VoidVal;
3822e5dd7070Spatrick }
3823e5dd7070Spatrick
3824*12c85518Srobert QualType Deduced = AT->getDeducedType();
3825*12c85518Srobert {
3826*12c85518Srobert // Otherwise, [...] deduce a value for U using the rules of template
3827*12c85518Srobert // argument deduction.
3828*12c85518Srobert TemplateDeductionInfo Info(RetExpr->getExprLoc());
3829*12c85518Srobert TemplateDeductionResult Res =
3830*12c85518Srobert DeduceAutoType(OrigResultType, RetExpr, Deduced, Info);
3831*12c85518Srobert if (Res != TDK_Success && FD->isInvalidDecl())
3832*12c85518Srobert return true;
3833*12c85518Srobert switch (Res) {
3834*12c85518Srobert case TDK_Success:
3835*12c85518Srobert break;
3836*12c85518Srobert case TDK_AlreadyDiagnosed:
3837*12c85518Srobert return true;
3838*12c85518Srobert case TDK_Inconsistent: {
3839*12c85518Srobert // If a function with a declared return type that contains a placeholder
3840*12c85518Srobert // type has multiple return statements, the return type is deduced for
3841*12c85518Srobert // each return statement. [...] if the type deduced is not the same in
3842*12c85518Srobert // each deduction, the program is ill-formed.
3843*12c85518Srobert const LambdaScopeInfo *LambdaSI = getCurLambda();
3844*12c85518Srobert if (LambdaSI && LambdaSI->HasImplicitReturnType)
3845*12c85518Srobert Diag(ReturnLoc, diag::err_typecheck_missing_return_type_incompatible)
3846*12c85518Srobert << Info.SecondArg << Info.FirstArg << true /*IsLambda*/;
3847*12c85518Srobert else
3848*12c85518Srobert Diag(ReturnLoc, diag::err_auto_fn_different_deductions)
3849*12c85518Srobert << (AT->isDecltypeAuto() ? 1 : 0) << Info.SecondArg
3850*12c85518Srobert << Info.FirstArg;
3851*12c85518Srobert return true;
3852*12c85518Srobert }
3853*12c85518Srobert default:
3854*12c85518Srobert Diag(RetExpr->getExprLoc(), diag::err_auto_fn_deduction_failure)
3855*12c85518Srobert << OrigResultType.getType() << RetExpr->getType();
3856*12c85518Srobert return true;
3857*12c85518Srobert }
3858*12c85518Srobert }
3859*12c85518Srobert
3860*12c85518Srobert // If a local type is part of the returned type, mark its fields as
3861*12c85518Srobert // referenced.
3862*12c85518Srobert LocalTypedefNameReferencer(*this).TraverseType(RetExpr->getType());
3863*12c85518Srobert
3864e5dd7070Spatrick // CUDA: Kernel function must have 'void' return type.
3865*12c85518Srobert if (getLangOpts().CUDA && FD->hasAttr<CUDAGlobalAttr>() &&
3866*12c85518Srobert !Deduced->isVoidType()) {
3867e5dd7070Spatrick Diag(FD->getLocation(), diag::err_kern_type_not_void_return)
3868e5dd7070Spatrick << FD->getType() << FD->getSourceRange();
3869e5dd7070Spatrick return true;
3870e5dd7070Spatrick }
3871e5dd7070Spatrick
3872*12c85518Srobert if (!FD->isInvalidDecl() && AT->getDeducedType() != Deduced)
3873e5dd7070Spatrick // Update all declarations of the function to have the deduced return type.
3874e5dd7070Spatrick Context.adjustDeducedFunctionResultType(FD, Deduced);
3875e5dd7070Spatrick
3876e5dd7070Spatrick return false;
3877e5dd7070Spatrick }
3878e5dd7070Spatrick
3879e5dd7070Spatrick StmtResult
ActOnReturnStmt(SourceLocation ReturnLoc,Expr * RetValExp,Scope * CurScope)3880e5dd7070Spatrick Sema::ActOnReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp,
3881e5dd7070Spatrick Scope *CurScope) {
3882e5dd7070Spatrick // Correct typos, in case the containing function returns 'auto' and
3883e5dd7070Spatrick // RetValExp should determine the deduced type.
3884a9ac8606Spatrick ExprResult RetVal = CorrectDelayedTyposInExpr(
3885a9ac8606Spatrick RetValExp, nullptr, /*RecoverUncorrectedTypos=*/true);
3886e5dd7070Spatrick if (RetVal.isInvalid())
3887e5dd7070Spatrick return StmtError();
3888*12c85518Srobert StmtResult R =
3889*12c85518Srobert BuildReturnStmt(ReturnLoc, RetVal.get(), /*AllowRecovery=*/true);
3890*12c85518Srobert if (R.isInvalid() || ExprEvalContexts.back().isDiscardedStatementContext())
3891e5dd7070Spatrick return R;
3892e5dd7070Spatrick
3893*12c85518Srobert VarDecl *VD =
3894*12c85518Srobert const_cast<VarDecl *>(cast<ReturnStmt>(R.get())->getNRVOCandidate());
3895*12c85518Srobert
3896*12c85518Srobert CurScope->updateNRVOCandidate(VD);
3897e5dd7070Spatrick
3898e5dd7070Spatrick CheckJumpOutOfSEHFinally(*this, ReturnLoc, *CurScope->getFnParent());
3899e5dd7070Spatrick
3900e5dd7070Spatrick return R;
3901e5dd7070Spatrick }
3902e5dd7070Spatrick
CheckSimplerImplicitMovesMSVCWorkaround(const Sema & S,const Expr * E)3903a9ac8606Spatrick static bool CheckSimplerImplicitMovesMSVCWorkaround(const Sema &S,
3904a9ac8606Spatrick const Expr *E) {
3905a9ac8606Spatrick if (!E || !S.getLangOpts().CPlusPlus2b || !S.getLangOpts().MSVCCompat)
3906a9ac8606Spatrick return false;
3907a9ac8606Spatrick const Decl *D = E->getReferencedDeclOfCallee();
3908a9ac8606Spatrick if (!D || !S.SourceMgr.isInSystemHeader(D->getLocation()))
3909a9ac8606Spatrick return false;
3910a9ac8606Spatrick for (const DeclContext *DC = D->getDeclContext(); DC; DC = DC->getParent()) {
3911a9ac8606Spatrick if (DC->isStdNamespace())
3912a9ac8606Spatrick return true;
3913a9ac8606Spatrick }
3914a9ac8606Spatrick return false;
3915a9ac8606Spatrick }
3916a9ac8606Spatrick
BuildReturnStmt(SourceLocation ReturnLoc,Expr * RetValExp,bool AllowRecovery)3917*12c85518Srobert StmtResult Sema::BuildReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp,
3918*12c85518Srobert bool AllowRecovery) {
3919e5dd7070Spatrick // Check for unexpanded parameter packs.
3920e5dd7070Spatrick if (RetValExp && DiagnoseUnexpandedParameterPack(RetValExp))
3921e5dd7070Spatrick return StmtError();
3922e5dd7070Spatrick
3923*12c85518Srobert // HACK: We suppress simpler implicit move here in msvc compatibility mode
3924a9ac8606Spatrick // just as a temporary work around, as the MSVC STL has issues with
3925a9ac8606Spatrick // this change.
3926a9ac8606Spatrick bool SupressSimplerImplicitMoves =
3927a9ac8606Spatrick CheckSimplerImplicitMovesMSVCWorkaround(*this, RetValExp);
3928a9ac8606Spatrick NamedReturnInfo NRInfo = getNamedReturnInfo(
3929a9ac8606Spatrick RetValExp, SupressSimplerImplicitMoves ? SimplerImplicitMoveMode::ForceOff
3930a9ac8606Spatrick : SimplerImplicitMoveMode::Normal);
3931a9ac8606Spatrick
3932e5dd7070Spatrick if (isa<CapturingScopeInfo>(getCurFunction()))
3933a9ac8606Spatrick return ActOnCapScopeReturnStmt(ReturnLoc, RetValExp, NRInfo,
3934a9ac8606Spatrick SupressSimplerImplicitMoves);
3935e5dd7070Spatrick
3936e5dd7070Spatrick QualType FnRetType;
3937e5dd7070Spatrick QualType RelatedRetType;
3938e5dd7070Spatrick const AttrVec *Attrs = nullptr;
3939e5dd7070Spatrick bool isObjCMethod = false;
3940e5dd7070Spatrick
3941e5dd7070Spatrick if (const FunctionDecl *FD = getCurFunctionDecl()) {
3942e5dd7070Spatrick FnRetType = FD->getReturnType();
3943e5dd7070Spatrick if (FD->hasAttrs())
3944e5dd7070Spatrick Attrs = &FD->getAttrs();
3945e5dd7070Spatrick if (FD->isNoReturn())
3946a9ac8606Spatrick Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr) << FD;
3947e5dd7070Spatrick if (FD->isMain() && RetValExp)
3948e5dd7070Spatrick if (isa<CXXBoolLiteralExpr>(RetValExp))
3949e5dd7070Spatrick Diag(ReturnLoc, diag::warn_main_returns_bool_literal)
3950e5dd7070Spatrick << RetValExp->getSourceRange();
3951ec727ea7Spatrick if (FD->hasAttr<CmseNSEntryAttr>() && RetValExp) {
3952ec727ea7Spatrick if (const auto *RT = dyn_cast<RecordType>(FnRetType.getCanonicalType())) {
3953ec727ea7Spatrick if (RT->getDecl()->isOrContainsUnion())
3954ec727ea7Spatrick Diag(RetValExp->getBeginLoc(), diag::warn_cmse_nonsecure_union) << 1;
3955ec727ea7Spatrick }
3956ec727ea7Spatrick }
3957e5dd7070Spatrick } else if (ObjCMethodDecl *MD = getCurMethodDecl()) {
3958e5dd7070Spatrick FnRetType = MD->getReturnType();
3959e5dd7070Spatrick isObjCMethod = true;
3960e5dd7070Spatrick if (MD->hasAttrs())
3961e5dd7070Spatrick Attrs = &MD->getAttrs();
3962e5dd7070Spatrick if (MD->hasRelatedResultType() && MD->getClassInterface()) {
3963e5dd7070Spatrick // In the implementation of a method with a related return type, the
3964e5dd7070Spatrick // type used to type-check the validity of return statements within the
3965e5dd7070Spatrick // method body is a pointer to the type of the class being implemented.
3966e5dd7070Spatrick RelatedRetType = Context.getObjCInterfaceType(MD->getClassInterface());
3967e5dd7070Spatrick RelatedRetType = Context.getObjCObjectPointerType(RelatedRetType);
3968e5dd7070Spatrick }
3969e5dd7070Spatrick } else // If we don't have a function/method context, bail.
3970e5dd7070Spatrick return StmtError();
3971e5dd7070Spatrick
3972e5dd7070Spatrick // C++1z: discarded return statements are not considered when deducing a
3973e5dd7070Spatrick // return type.
3974*12c85518Srobert if (ExprEvalContexts.back().isDiscardedStatementContext() &&
3975e5dd7070Spatrick FnRetType->getContainedAutoType()) {
3976e5dd7070Spatrick if (RetValExp) {
3977e5dd7070Spatrick ExprResult ER =
3978e5dd7070Spatrick ActOnFinishFullExpr(RetValExp, ReturnLoc, /*DiscardedValue*/ false);
3979e5dd7070Spatrick if (ER.isInvalid())
3980e5dd7070Spatrick return StmtError();
3981e5dd7070Spatrick RetValExp = ER.get();
3982e5dd7070Spatrick }
3983e5dd7070Spatrick return ReturnStmt::Create(Context, ReturnLoc, RetValExp,
3984e5dd7070Spatrick /* NRVOCandidate=*/nullptr);
3985e5dd7070Spatrick }
3986e5dd7070Spatrick
3987e5dd7070Spatrick // FIXME: Add a flag to the ScopeInfo to indicate whether we're performing
3988e5dd7070Spatrick // deduction.
3989e5dd7070Spatrick if (getLangOpts().CPlusPlus14) {
3990e5dd7070Spatrick if (AutoType *AT = FnRetType->getContainedAutoType()) {
3991e5dd7070Spatrick FunctionDecl *FD = cast<FunctionDecl>(CurContext);
3992a9ac8606Spatrick // If we've already decided this function is invalid, e.g. because
3993a9ac8606Spatrick // we saw a `return` whose expression had an error, don't keep
3994a9ac8606Spatrick // trying to deduce its return type.
3995*12c85518Srobert // (Some return values may be needlessly wrapped in RecoveryExpr).
3996*12c85518Srobert if (FD->isInvalidDecl() ||
3997*12c85518Srobert DeduceFunctionTypeFromReturnExpr(FD, ReturnLoc, RetValExp, AT)) {
3998e5dd7070Spatrick FD->setInvalidDecl();
3999*12c85518Srobert if (!AllowRecovery)
4000e5dd7070Spatrick return StmtError();
4001*12c85518Srobert // The deduction failure is diagnosed and marked, try to recover.
4002*12c85518Srobert if (RetValExp) {
4003*12c85518Srobert // Wrap return value with a recovery expression of the previous type.
4004*12c85518Srobert // If no deduction yet, use DependentTy.
4005*12c85518Srobert auto Recovery = CreateRecoveryExpr(
4006*12c85518Srobert RetValExp->getBeginLoc(), RetValExp->getEndLoc(), RetValExp,
4007*12c85518Srobert AT->isDeduced() ? FnRetType : QualType());
4008*12c85518Srobert if (Recovery.isInvalid())
4009*12c85518Srobert return StmtError();
4010*12c85518Srobert RetValExp = Recovery.get();
4011*12c85518Srobert } else {
4012*12c85518Srobert // Nothing to do: a ReturnStmt with no value is fine recovery.
4013*12c85518Srobert }
4014e5dd7070Spatrick } else {
4015e5dd7070Spatrick FnRetType = FD->getReturnType();
4016e5dd7070Spatrick }
4017e5dd7070Spatrick }
4018e5dd7070Spatrick }
4019a9ac8606Spatrick const VarDecl *NRVOCandidate = getCopyElisionCandidate(NRInfo, FnRetType);
4020e5dd7070Spatrick
4021e5dd7070Spatrick bool HasDependentReturnType = FnRetType->isDependentType();
4022e5dd7070Spatrick
4023e5dd7070Spatrick ReturnStmt *Result = nullptr;
4024e5dd7070Spatrick if (FnRetType->isVoidType()) {
4025e5dd7070Spatrick if (RetValExp) {
4026*12c85518Srobert if (auto *ILE = dyn_cast<InitListExpr>(RetValExp)) {
4027e5dd7070Spatrick // We simply never allow init lists as the return value of void
4028e5dd7070Spatrick // functions. This is compatible because this was never allowed before,
4029e5dd7070Spatrick // so there's no legacy code to deal with.
4030e5dd7070Spatrick NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
4031e5dd7070Spatrick int FunctionKind = 0;
4032e5dd7070Spatrick if (isa<ObjCMethodDecl>(CurDecl))
4033e5dd7070Spatrick FunctionKind = 1;
4034e5dd7070Spatrick else if (isa<CXXConstructorDecl>(CurDecl))
4035e5dd7070Spatrick FunctionKind = 2;
4036e5dd7070Spatrick else if (isa<CXXDestructorDecl>(CurDecl))
4037e5dd7070Spatrick FunctionKind = 3;
4038e5dd7070Spatrick
4039e5dd7070Spatrick Diag(ReturnLoc, diag::err_return_init_list)
4040a9ac8606Spatrick << CurDecl << FunctionKind << RetValExp->getSourceRange();
4041e5dd7070Spatrick
4042*12c85518Srobert // Preserve the initializers in the AST.
4043*12c85518Srobert RetValExp = AllowRecovery
4044*12c85518Srobert ? CreateRecoveryExpr(ILE->getLBraceLoc(),
4045*12c85518Srobert ILE->getRBraceLoc(), ILE->inits())
4046*12c85518Srobert .get()
4047*12c85518Srobert : nullptr;
4048e5dd7070Spatrick } else if (!RetValExp->isTypeDependent()) {
4049e5dd7070Spatrick // C99 6.8.6.4p1 (ext_ since GCC warns)
4050e5dd7070Spatrick unsigned D = diag::ext_return_has_expr;
4051e5dd7070Spatrick if (RetValExp->getType()->isVoidType()) {
4052e5dd7070Spatrick NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
4053e5dd7070Spatrick if (isa<CXXConstructorDecl>(CurDecl) ||
4054e5dd7070Spatrick isa<CXXDestructorDecl>(CurDecl))
4055e5dd7070Spatrick D = diag::err_ctor_dtor_returns_void;
4056e5dd7070Spatrick else
4057e5dd7070Spatrick D = diag::ext_return_has_void_expr;
4058e5dd7070Spatrick }
4059e5dd7070Spatrick else {
4060e5dd7070Spatrick ExprResult Result = RetValExp;
4061e5dd7070Spatrick Result = IgnoredValueConversions(Result.get());
4062e5dd7070Spatrick if (Result.isInvalid())
4063e5dd7070Spatrick return StmtError();
4064e5dd7070Spatrick RetValExp = Result.get();
4065e5dd7070Spatrick RetValExp = ImpCastExprToType(RetValExp,
4066e5dd7070Spatrick Context.VoidTy, CK_ToVoid).get();
4067e5dd7070Spatrick }
4068e5dd7070Spatrick // return of void in constructor/destructor is illegal in C++.
4069e5dd7070Spatrick if (D == diag::err_ctor_dtor_returns_void) {
4070e5dd7070Spatrick NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
4071a9ac8606Spatrick Diag(ReturnLoc, D) << CurDecl << isa<CXXDestructorDecl>(CurDecl)
4072e5dd7070Spatrick << RetValExp->getSourceRange();
4073e5dd7070Spatrick }
4074e5dd7070Spatrick // return (some void expression); is legal in C++.
4075e5dd7070Spatrick else if (D != diag::ext_return_has_void_expr ||
4076e5dd7070Spatrick !getLangOpts().CPlusPlus) {
4077e5dd7070Spatrick NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
4078e5dd7070Spatrick
4079e5dd7070Spatrick int FunctionKind = 0;
4080e5dd7070Spatrick if (isa<ObjCMethodDecl>(CurDecl))
4081e5dd7070Spatrick FunctionKind = 1;
4082e5dd7070Spatrick else if (isa<CXXConstructorDecl>(CurDecl))
4083e5dd7070Spatrick FunctionKind = 2;
4084e5dd7070Spatrick else if (isa<CXXDestructorDecl>(CurDecl))
4085e5dd7070Spatrick FunctionKind = 3;
4086e5dd7070Spatrick
4087e5dd7070Spatrick Diag(ReturnLoc, D)
4088a9ac8606Spatrick << CurDecl << FunctionKind << RetValExp->getSourceRange();
4089e5dd7070Spatrick }
4090e5dd7070Spatrick }
4091e5dd7070Spatrick
4092e5dd7070Spatrick if (RetValExp) {
4093e5dd7070Spatrick ExprResult ER =
4094e5dd7070Spatrick ActOnFinishFullExpr(RetValExp, ReturnLoc, /*DiscardedValue*/ false);
4095e5dd7070Spatrick if (ER.isInvalid())
4096e5dd7070Spatrick return StmtError();
4097e5dd7070Spatrick RetValExp = ER.get();
4098e5dd7070Spatrick }
4099e5dd7070Spatrick }
4100e5dd7070Spatrick
4101e5dd7070Spatrick Result = ReturnStmt::Create(Context, ReturnLoc, RetValExp,
4102e5dd7070Spatrick /* NRVOCandidate=*/nullptr);
4103e5dd7070Spatrick } else if (!RetValExp && !HasDependentReturnType) {
4104e5dd7070Spatrick FunctionDecl *FD = getCurFunctionDecl();
4105e5dd7070Spatrick
4106*12c85518Srobert if ((FD && FD->isInvalidDecl()) || FnRetType->containsErrors()) {
4107*12c85518Srobert // The intended return type might have been "void", so don't warn.
4108*12c85518Srobert } else if (getLangOpts().CPlusPlus11 && FD && FD->isConstexpr()) {
4109e5dd7070Spatrick // C++11 [stmt.return]p2
4110a9ac8606Spatrick Diag(ReturnLoc, diag::err_constexpr_return_missing_expr)
4111a9ac8606Spatrick << FD << FD->isConsteval();
4112e5dd7070Spatrick FD->setInvalidDecl();
4113e5dd7070Spatrick } else {
4114a9ac8606Spatrick // C99 6.8.6.4p1 (ext_ since GCC warns)
4115e5dd7070Spatrick // C90 6.6.6.4p4
4116a9ac8606Spatrick unsigned DiagID = getLangOpts().C99 ? diag::ext_return_missing_expr
4117a9ac8606Spatrick : diag::warn_return_missing_expr;
4118a9ac8606Spatrick // Note that at this point one of getCurFunctionDecl() or
4119a9ac8606Spatrick // getCurMethodDecl() must be non-null (see above).
4120a9ac8606Spatrick assert((getCurFunctionDecl() || getCurMethodDecl()) &&
4121a9ac8606Spatrick "Not in a FunctionDecl or ObjCMethodDecl?");
4122a9ac8606Spatrick bool IsMethod = FD == nullptr;
4123a9ac8606Spatrick const NamedDecl *ND =
4124a9ac8606Spatrick IsMethod ? cast<NamedDecl>(getCurMethodDecl()) : cast<NamedDecl>(FD);
4125a9ac8606Spatrick Diag(ReturnLoc, DiagID) << ND << IsMethod;
4126e5dd7070Spatrick }
4127e5dd7070Spatrick
4128e5dd7070Spatrick Result = ReturnStmt::Create(Context, ReturnLoc, /* RetExpr=*/nullptr,
4129e5dd7070Spatrick /* NRVOCandidate=*/nullptr);
4130e5dd7070Spatrick } else {
4131e5dd7070Spatrick assert(RetValExp || HasDependentReturnType);
4132e5dd7070Spatrick QualType RetType = RelatedRetType.isNull() ? FnRetType : RelatedRetType;
4133e5dd7070Spatrick
4134e5dd7070Spatrick // C99 6.8.6.4p3(136): The return statement is not an assignment. The
4135e5dd7070Spatrick // overlap restriction of subclause 6.5.16.1 does not apply to the case of
4136e5dd7070Spatrick // function return.
4137e5dd7070Spatrick
4138e5dd7070Spatrick // In C++ the return statement is handled via a copy initialization,
4139e5dd7070Spatrick // the C version of which boils down to CheckSingleAssignmentConstraints.
4140e5dd7070Spatrick if (!HasDependentReturnType && !RetValExp->isTypeDependent()) {
4141e5dd7070Spatrick // we have a non-void function with an expression, continue checking
4142a9ac8606Spatrick InitializedEntity Entity =
4143a9ac8606Spatrick InitializedEntity::InitializeResult(ReturnLoc, RetType);
4144a9ac8606Spatrick ExprResult Res = PerformMoveOrCopyInitialization(
4145a9ac8606Spatrick Entity, NRInfo, RetValExp, SupressSimplerImplicitMoves);
4146*12c85518Srobert if (Res.isInvalid() && AllowRecovery)
4147*12c85518Srobert Res = CreateRecoveryExpr(RetValExp->getBeginLoc(),
4148*12c85518Srobert RetValExp->getEndLoc(), RetValExp, RetType);
4149e5dd7070Spatrick if (Res.isInvalid()) {
4150e5dd7070Spatrick // FIXME: Clean up temporaries here anyway?
4151e5dd7070Spatrick return StmtError();
4152e5dd7070Spatrick }
4153e5dd7070Spatrick RetValExp = Res.getAs<Expr>();
4154e5dd7070Spatrick
4155e5dd7070Spatrick // If we have a related result type, we need to implicitly
4156e5dd7070Spatrick // convert back to the formal result type. We can't pretend to
4157e5dd7070Spatrick // initialize the result again --- we might end double-retaining
4158e5dd7070Spatrick // --- so instead we initialize a notional temporary.
4159e5dd7070Spatrick if (!RelatedRetType.isNull()) {
4160e5dd7070Spatrick Entity = InitializedEntity::InitializeRelatedResult(getCurMethodDecl(),
4161e5dd7070Spatrick FnRetType);
4162e5dd7070Spatrick Res = PerformCopyInitialization(Entity, ReturnLoc, RetValExp);
4163e5dd7070Spatrick if (Res.isInvalid()) {
4164e5dd7070Spatrick // FIXME: Clean up temporaries here anyway?
4165e5dd7070Spatrick return StmtError();
4166e5dd7070Spatrick }
4167e5dd7070Spatrick RetValExp = Res.getAs<Expr>();
4168e5dd7070Spatrick }
4169e5dd7070Spatrick
4170e5dd7070Spatrick CheckReturnValExpr(RetValExp, FnRetType, ReturnLoc, isObjCMethod, Attrs,
4171e5dd7070Spatrick getCurFunctionDecl());
4172e5dd7070Spatrick }
4173e5dd7070Spatrick
4174e5dd7070Spatrick if (RetValExp) {
4175e5dd7070Spatrick ExprResult ER =
4176e5dd7070Spatrick ActOnFinishFullExpr(RetValExp, ReturnLoc, /*DiscardedValue*/ false);
4177e5dd7070Spatrick if (ER.isInvalid())
4178e5dd7070Spatrick return StmtError();
4179e5dd7070Spatrick RetValExp = ER.get();
4180e5dd7070Spatrick }
4181e5dd7070Spatrick Result = ReturnStmt::Create(Context, ReturnLoc, RetValExp, NRVOCandidate);
4182e5dd7070Spatrick }
4183e5dd7070Spatrick
4184e5dd7070Spatrick // If we need to check for the named return value optimization, save the
4185e5dd7070Spatrick // return statement in our scope for later processing.
4186e5dd7070Spatrick if (Result->getNRVOCandidate())
4187e5dd7070Spatrick FunctionScopes.back()->Returns.push_back(Result);
4188e5dd7070Spatrick
4189e5dd7070Spatrick if (FunctionScopes.back()->FirstReturnLoc.isInvalid())
4190e5dd7070Spatrick FunctionScopes.back()->FirstReturnLoc = ReturnLoc;
4191e5dd7070Spatrick
4192e5dd7070Spatrick return Result;
4193e5dd7070Spatrick }
4194e5dd7070Spatrick
4195e5dd7070Spatrick StmtResult
ActOnObjCAtCatchStmt(SourceLocation AtLoc,SourceLocation RParen,Decl * Parm,Stmt * Body)4196e5dd7070Spatrick Sema::ActOnObjCAtCatchStmt(SourceLocation AtLoc,
4197e5dd7070Spatrick SourceLocation RParen, Decl *Parm,
4198e5dd7070Spatrick Stmt *Body) {
4199e5dd7070Spatrick VarDecl *Var = cast_or_null<VarDecl>(Parm);
4200e5dd7070Spatrick if (Var && Var->isInvalidDecl())
4201e5dd7070Spatrick return StmtError();
4202e5dd7070Spatrick
4203e5dd7070Spatrick return new (Context) ObjCAtCatchStmt(AtLoc, RParen, Var, Body);
4204e5dd7070Spatrick }
4205e5dd7070Spatrick
4206e5dd7070Spatrick StmtResult
ActOnObjCAtFinallyStmt(SourceLocation AtLoc,Stmt * Body)4207e5dd7070Spatrick Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, Stmt *Body) {
4208e5dd7070Spatrick return new (Context) ObjCAtFinallyStmt(AtLoc, Body);
4209e5dd7070Spatrick }
4210e5dd7070Spatrick
4211e5dd7070Spatrick StmtResult
ActOnObjCAtTryStmt(SourceLocation AtLoc,Stmt * Try,MultiStmtArg CatchStmts,Stmt * Finally)4212e5dd7070Spatrick Sema::ActOnObjCAtTryStmt(SourceLocation AtLoc, Stmt *Try,
4213e5dd7070Spatrick MultiStmtArg CatchStmts, Stmt *Finally) {
4214e5dd7070Spatrick if (!getLangOpts().ObjCExceptions)
4215e5dd7070Spatrick Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@try";
4216e5dd7070Spatrick
4217*12c85518Srobert // Objective-C try is incompatible with SEH __try.
4218*12c85518Srobert sema::FunctionScopeInfo *FSI = getCurFunction();
4219*12c85518Srobert if (FSI->FirstSEHTryLoc.isValid()) {
4220*12c85518Srobert Diag(AtLoc, diag::err_mixing_cxx_try_seh_try) << 1;
4221*12c85518Srobert Diag(FSI->FirstSEHTryLoc, diag::note_conflicting_try_here) << "'__try'";
4222*12c85518Srobert }
4223*12c85518Srobert
4224*12c85518Srobert FSI->setHasObjCTry(AtLoc);
4225e5dd7070Spatrick unsigned NumCatchStmts = CatchStmts.size();
4226e5dd7070Spatrick return ObjCAtTryStmt::Create(Context, AtLoc, Try, CatchStmts.data(),
4227e5dd7070Spatrick NumCatchStmts, Finally);
4228e5dd7070Spatrick }
4229e5dd7070Spatrick
BuildObjCAtThrowStmt(SourceLocation AtLoc,Expr * Throw)4230e5dd7070Spatrick StmtResult Sema::BuildObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw) {
4231e5dd7070Spatrick if (Throw) {
4232e5dd7070Spatrick ExprResult Result = DefaultLvalueConversion(Throw);
4233e5dd7070Spatrick if (Result.isInvalid())
4234e5dd7070Spatrick return StmtError();
4235e5dd7070Spatrick
4236e5dd7070Spatrick Result = ActOnFinishFullExpr(Result.get(), /*DiscardedValue*/ false);
4237e5dd7070Spatrick if (Result.isInvalid())
4238e5dd7070Spatrick return StmtError();
4239e5dd7070Spatrick Throw = Result.get();
4240e5dd7070Spatrick
4241e5dd7070Spatrick QualType ThrowType = Throw->getType();
4242e5dd7070Spatrick // Make sure the expression type is an ObjC pointer or "void *".
4243e5dd7070Spatrick if (!ThrowType->isDependentType() &&
4244e5dd7070Spatrick !ThrowType->isObjCObjectPointerType()) {
4245e5dd7070Spatrick const PointerType *PT = ThrowType->getAs<PointerType>();
4246e5dd7070Spatrick if (!PT || !PT->getPointeeType()->isVoidType())
4247e5dd7070Spatrick return StmtError(Diag(AtLoc, diag::err_objc_throw_expects_object)
4248e5dd7070Spatrick << Throw->getType() << Throw->getSourceRange());
4249e5dd7070Spatrick }
4250e5dd7070Spatrick }
4251e5dd7070Spatrick
4252e5dd7070Spatrick return new (Context) ObjCAtThrowStmt(AtLoc, Throw);
4253e5dd7070Spatrick }
4254e5dd7070Spatrick
4255e5dd7070Spatrick StmtResult
ActOnObjCAtThrowStmt(SourceLocation AtLoc,Expr * Throw,Scope * CurScope)4256e5dd7070Spatrick Sema::ActOnObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw,
4257e5dd7070Spatrick Scope *CurScope) {
4258e5dd7070Spatrick if (!getLangOpts().ObjCExceptions)
4259e5dd7070Spatrick Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@throw";
4260e5dd7070Spatrick
4261e5dd7070Spatrick if (!Throw) {
4262e5dd7070Spatrick // @throw without an expression designates a rethrow (which must occur
4263e5dd7070Spatrick // in the context of an @catch clause).
4264e5dd7070Spatrick Scope *AtCatchParent = CurScope;
4265e5dd7070Spatrick while (AtCatchParent && !AtCatchParent->isAtCatchScope())
4266e5dd7070Spatrick AtCatchParent = AtCatchParent->getParent();
4267e5dd7070Spatrick if (!AtCatchParent)
4268e5dd7070Spatrick return StmtError(Diag(AtLoc, diag::err_rethrow_used_outside_catch));
4269e5dd7070Spatrick }
4270e5dd7070Spatrick return BuildObjCAtThrowStmt(AtLoc, Throw);
4271e5dd7070Spatrick }
4272e5dd7070Spatrick
4273e5dd7070Spatrick ExprResult
ActOnObjCAtSynchronizedOperand(SourceLocation atLoc,Expr * operand)4274e5dd7070Spatrick Sema::ActOnObjCAtSynchronizedOperand(SourceLocation atLoc, Expr *operand) {
4275e5dd7070Spatrick ExprResult result = DefaultLvalueConversion(operand);
4276e5dd7070Spatrick if (result.isInvalid())
4277e5dd7070Spatrick return ExprError();
4278e5dd7070Spatrick operand = result.get();
4279e5dd7070Spatrick
4280e5dd7070Spatrick // Make sure the expression type is an ObjC pointer or "void *".
4281e5dd7070Spatrick QualType type = operand->getType();
4282e5dd7070Spatrick if (!type->isDependentType() &&
4283e5dd7070Spatrick !type->isObjCObjectPointerType()) {
4284e5dd7070Spatrick const PointerType *pointerType = type->getAs<PointerType>();
4285e5dd7070Spatrick if (!pointerType || !pointerType->getPointeeType()->isVoidType()) {
4286e5dd7070Spatrick if (getLangOpts().CPlusPlus) {
4287e5dd7070Spatrick if (RequireCompleteType(atLoc, type,
4288e5dd7070Spatrick diag::err_incomplete_receiver_type))
4289e5dd7070Spatrick return Diag(atLoc, diag::err_objc_synchronized_expects_object)
4290e5dd7070Spatrick << type << operand->getSourceRange();
4291e5dd7070Spatrick
4292e5dd7070Spatrick ExprResult result = PerformContextuallyConvertToObjCPointer(operand);
4293e5dd7070Spatrick if (result.isInvalid())
4294e5dd7070Spatrick return ExprError();
4295e5dd7070Spatrick if (!result.isUsable())
4296e5dd7070Spatrick return Diag(atLoc, diag::err_objc_synchronized_expects_object)
4297e5dd7070Spatrick << type << operand->getSourceRange();
4298e5dd7070Spatrick
4299e5dd7070Spatrick operand = result.get();
4300e5dd7070Spatrick } else {
4301e5dd7070Spatrick return Diag(atLoc, diag::err_objc_synchronized_expects_object)
4302e5dd7070Spatrick << type << operand->getSourceRange();
4303e5dd7070Spatrick }
4304e5dd7070Spatrick }
4305e5dd7070Spatrick }
4306e5dd7070Spatrick
4307e5dd7070Spatrick // The operand to @synchronized is a full-expression.
4308e5dd7070Spatrick return ActOnFinishFullExpr(operand, /*DiscardedValue*/ false);
4309e5dd7070Spatrick }
4310e5dd7070Spatrick
4311e5dd7070Spatrick StmtResult
ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc,Expr * SyncExpr,Stmt * SyncBody)4312e5dd7070Spatrick Sema::ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc, Expr *SyncExpr,
4313e5dd7070Spatrick Stmt *SyncBody) {
4314e5dd7070Spatrick // We can't jump into or indirect-jump out of a @synchronized block.
4315e5dd7070Spatrick setFunctionHasBranchProtectedScope();
4316e5dd7070Spatrick return new (Context) ObjCAtSynchronizedStmt(AtLoc, SyncExpr, SyncBody);
4317e5dd7070Spatrick }
4318e5dd7070Spatrick
4319e5dd7070Spatrick /// ActOnCXXCatchBlock - Takes an exception declaration and a handler block
4320e5dd7070Spatrick /// and creates a proper catch handler from them.
4321e5dd7070Spatrick StmtResult
ActOnCXXCatchBlock(SourceLocation CatchLoc,Decl * ExDecl,Stmt * HandlerBlock)4322e5dd7070Spatrick Sema::ActOnCXXCatchBlock(SourceLocation CatchLoc, Decl *ExDecl,
4323e5dd7070Spatrick Stmt *HandlerBlock) {
4324e5dd7070Spatrick // There's nothing to test that ActOnExceptionDecl didn't already test.
4325e5dd7070Spatrick return new (Context)
4326e5dd7070Spatrick CXXCatchStmt(CatchLoc, cast_or_null<VarDecl>(ExDecl), HandlerBlock);
4327e5dd7070Spatrick }
4328e5dd7070Spatrick
4329e5dd7070Spatrick StmtResult
ActOnObjCAutoreleasePoolStmt(SourceLocation AtLoc,Stmt * Body)4330e5dd7070Spatrick Sema::ActOnObjCAutoreleasePoolStmt(SourceLocation AtLoc, Stmt *Body) {
4331e5dd7070Spatrick setFunctionHasBranchProtectedScope();
4332e5dd7070Spatrick return new (Context) ObjCAutoreleasePoolStmt(AtLoc, Body);
4333e5dd7070Spatrick }
4334e5dd7070Spatrick
4335e5dd7070Spatrick namespace {
4336e5dd7070Spatrick class CatchHandlerType {
4337e5dd7070Spatrick QualType QT;
4338e5dd7070Spatrick unsigned IsPointer : 1;
4339e5dd7070Spatrick
4340e5dd7070Spatrick // This is a special constructor to be used only with DenseMapInfo's
4341e5dd7070Spatrick // getEmptyKey() and getTombstoneKey() functions.
4342e5dd7070Spatrick friend struct llvm::DenseMapInfo<CatchHandlerType>;
4343e5dd7070Spatrick enum Unique { ForDenseMap };
CatchHandlerType(QualType QT,Unique)4344e5dd7070Spatrick CatchHandlerType(QualType QT, Unique) : QT(QT), IsPointer(false) {}
4345e5dd7070Spatrick
4346e5dd7070Spatrick public:
4347e5dd7070Spatrick /// Used when creating a CatchHandlerType from a handler type; will determine
4348e5dd7070Spatrick /// whether the type is a pointer or reference and will strip off the top
4349e5dd7070Spatrick /// level pointer and cv-qualifiers.
CatchHandlerType(QualType Q)4350e5dd7070Spatrick CatchHandlerType(QualType Q) : QT(Q), IsPointer(false) {
4351e5dd7070Spatrick if (QT->isPointerType())
4352e5dd7070Spatrick IsPointer = true;
4353e5dd7070Spatrick
4354e5dd7070Spatrick if (IsPointer || QT->isReferenceType())
4355e5dd7070Spatrick QT = QT->getPointeeType();
4356e5dd7070Spatrick QT = QT.getUnqualifiedType();
4357e5dd7070Spatrick }
4358e5dd7070Spatrick
4359e5dd7070Spatrick /// Used when creating a CatchHandlerType from a base class type; pretends the
4360e5dd7070Spatrick /// type passed in had the pointer qualifier, does not need to get an
4361e5dd7070Spatrick /// unqualified type.
CatchHandlerType(QualType QT,bool IsPointer)4362e5dd7070Spatrick CatchHandlerType(QualType QT, bool IsPointer)
4363e5dd7070Spatrick : QT(QT), IsPointer(IsPointer) {}
4364e5dd7070Spatrick
underlying() const4365e5dd7070Spatrick QualType underlying() const { return QT; }
isPointer() const4366e5dd7070Spatrick bool isPointer() const { return IsPointer; }
4367e5dd7070Spatrick
operator ==(const CatchHandlerType & LHS,const CatchHandlerType & RHS)4368e5dd7070Spatrick friend bool operator==(const CatchHandlerType &LHS,
4369e5dd7070Spatrick const CatchHandlerType &RHS) {
4370e5dd7070Spatrick // If the pointer qualification does not match, we can return early.
4371e5dd7070Spatrick if (LHS.IsPointer != RHS.IsPointer)
4372e5dd7070Spatrick return false;
4373e5dd7070Spatrick // Otherwise, check the underlying type without cv-qualifiers.
4374e5dd7070Spatrick return LHS.QT == RHS.QT;
4375e5dd7070Spatrick }
4376e5dd7070Spatrick };
4377e5dd7070Spatrick } // namespace
4378e5dd7070Spatrick
4379e5dd7070Spatrick namespace llvm {
4380e5dd7070Spatrick template <> struct DenseMapInfo<CatchHandlerType> {
getEmptyKeyllvm::DenseMapInfo4381e5dd7070Spatrick static CatchHandlerType getEmptyKey() {
4382e5dd7070Spatrick return CatchHandlerType(DenseMapInfo<QualType>::getEmptyKey(),
4383e5dd7070Spatrick CatchHandlerType::ForDenseMap);
4384e5dd7070Spatrick }
4385e5dd7070Spatrick
getTombstoneKeyllvm::DenseMapInfo4386e5dd7070Spatrick static CatchHandlerType getTombstoneKey() {
4387e5dd7070Spatrick return CatchHandlerType(DenseMapInfo<QualType>::getTombstoneKey(),
4388e5dd7070Spatrick CatchHandlerType::ForDenseMap);
4389e5dd7070Spatrick }
4390e5dd7070Spatrick
getHashValuellvm::DenseMapInfo4391e5dd7070Spatrick static unsigned getHashValue(const CatchHandlerType &Base) {
4392e5dd7070Spatrick return DenseMapInfo<QualType>::getHashValue(Base.underlying());
4393e5dd7070Spatrick }
4394e5dd7070Spatrick
isEqualllvm::DenseMapInfo4395e5dd7070Spatrick static bool isEqual(const CatchHandlerType &LHS,
4396e5dd7070Spatrick const CatchHandlerType &RHS) {
4397e5dd7070Spatrick return LHS == RHS;
4398e5dd7070Spatrick }
4399e5dd7070Spatrick };
4400e5dd7070Spatrick }
4401e5dd7070Spatrick
4402e5dd7070Spatrick namespace {
4403e5dd7070Spatrick class CatchTypePublicBases {
4404e5dd7070Spatrick ASTContext &Ctx;
4405e5dd7070Spatrick const llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> &TypesToCheck;
4406e5dd7070Spatrick const bool CheckAgainstPointer;
4407e5dd7070Spatrick
4408e5dd7070Spatrick CXXCatchStmt *FoundHandler;
4409e5dd7070Spatrick CanQualType FoundHandlerType;
4410e5dd7070Spatrick
4411e5dd7070Spatrick public:
CatchTypePublicBases(ASTContext & Ctx,const llvm::DenseMap<CatchHandlerType,CXXCatchStmt * > & T,bool C)4412e5dd7070Spatrick CatchTypePublicBases(
4413e5dd7070Spatrick ASTContext &Ctx,
4414e5dd7070Spatrick const llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> &T, bool C)
4415e5dd7070Spatrick : Ctx(Ctx), TypesToCheck(T), CheckAgainstPointer(C),
4416e5dd7070Spatrick FoundHandler(nullptr) {}
4417e5dd7070Spatrick
getFoundHandler() const4418e5dd7070Spatrick CXXCatchStmt *getFoundHandler() const { return FoundHandler; }
getFoundHandlerType() const4419e5dd7070Spatrick CanQualType getFoundHandlerType() const { return FoundHandlerType; }
4420e5dd7070Spatrick
operator ()(const CXXBaseSpecifier * S,CXXBasePath &)4421e5dd7070Spatrick bool operator()(const CXXBaseSpecifier *S, CXXBasePath &) {
4422e5dd7070Spatrick if (S->getAccessSpecifier() == AccessSpecifier::AS_public) {
4423e5dd7070Spatrick CatchHandlerType Check(S->getType(), CheckAgainstPointer);
4424e5dd7070Spatrick const auto &M = TypesToCheck;
4425e5dd7070Spatrick auto I = M.find(Check);
4426e5dd7070Spatrick if (I != M.end()) {
4427e5dd7070Spatrick FoundHandler = I->second;
4428e5dd7070Spatrick FoundHandlerType = Ctx.getCanonicalType(S->getType());
4429e5dd7070Spatrick return true;
4430e5dd7070Spatrick }
4431e5dd7070Spatrick }
4432e5dd7070Spatrick return false;
4433e5dd7070Spatrick }
4434e5dd7070Spatrick };
4435e5dd7070Spatrick }
4436e5dd7070Spatrick
4437e5dd7070Spatrick /// ActOnCXXTryBlock - Takes a try compound-statement and a number of
4438e5dd7070Spatrick /// handlers and creates a try statement from them.
ActOnCXXTryBlock(SourceLocation TryLoc,Stmt * TryBlock,ArrayRef<Stmt * > Handlers)4439e5dd7070Spatrick StmtResult Sema::ActOnCXXTryBlock(SourceLocation TryLoc, Stmt *TryBlock,
4440e5dd7070Spatrick ArrayRef<Stmt *> Handlers) {
4441e5dd7070Spatrick // Don't report an error if 'try' is used in system headers.
4442e5dd7070Spatrick if (!getLangOpts().CXXExceptions &&
4443e5dd7070Spatrick !getSourceManager().isInSystemHeader(TryLoc) && !getLangOpts().CUDA) {
4444e5dd7070Spatrick // Delay error emission for the OpenMP device code.
4445e5dd7070Spatrick targetDiag(TryLoc, diag::err_exceptions_disabled) << "try";
4446e5dd7070Spatrick }
4447e5dd7070Spatrick
4448e5dd7070Spatrick // Exceptions aren't allowed in CUDA device code.
4449e5dd7070Spatrick if (getLangOpts().CUDA)
4450e5dd7070Spatrick CUDADiagIfDeviceCode(TryLoc, diag::err_cuda_device_exceptions)
4451e5dd7070Spatrick << "try" << CurrentCUDATarget();
4452e5dd7070Spatrick
4453e5dd7070Spatrick if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
4454e5dd7070Spatrick Diag(TryLoc, diag::err_omp_simd_region_cannot_use_stmt) << "try";
4455e5dd7070Spatrick
4456e5dd7070Spatrick sema::FunctionScopeInfo *FSI = getCurFunction();
4457e5dd7070Spatrick
4458e5dd7070Spatrick // C++ try is incompatible with SEH __try.
4459e5dd7070Spatrick if (!getLangOpts().Borland && FSI->FirstSEHTryLoc.isValid()) {
4460*12c85518Srobert Diag(TryLoc, diag::err_mixing_cxx_try_seh_try) << 0;
4461e5dd7070Spatrick Diag(FSI->FirstSEHTryLoc, diag::note_conflicting_try_here) << "'__try'";
4462e5dd7070Spatrick }
4463e5dd7070Spatrick
4464e5dd7070Spatrick const unsigned NumHandlers = Handlers.size();
4465e5dd7070Spatrick assert(!Handlers.empty() &&
4466e5dd7070Spatrick "The parser shouldn't call this if there are no handlers.");
4467e5dd7070Spatrick
4468e5dd7070Spatrick llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> HandledTypes;
4469e5dd7070Spatrick for (unsigned i = 0; i < NumHandlers; ++i) {
4470e5dd7070Spatrick CXXCatchStmt *H = cast<CXXCatchStmt>(Handlers[i]);
4471e5dd7070Spatrick
4472e5dd7070Spatrick // Diagnose when the handler is a catch-all handler, but it isn't the last
4473e5dd7070Spatrick // handler for the try block. [except.handle]p5. Also, skip exception
4474e5dd7070Spatrick // declarations that are invalid, since we can't usefully report on them.
4475e5dd7070Spatrick if (!H->getExceptionDecl()) {
4476e5dd7070Spatrick if (i < NumHandlers - 1)
4477e5dd7070Spatrick return StmtError(Diag(H->getBeginLoc(), diag::err_early_catch_all));
4478e5dd7070Spatrick continue;
4479e5dd7070Spatrick } else if (H->getExceptionDecl()->isInvalidDecl())
4480e5dd7070Spatrick continue;
4481e5dd7070Spatrick
4482e5dd7070Spatrick // Walk the type hierarchy to diagnose when this type has already been
4483e5dd7070Spatrick // handled (duplication), or cannot be handled (derivation inversion). We
4484e5dd7070Spatrick // ignore top-level cv-qualifiers, per [except.handle]p3
4485e5dd7070Spatrick CatchHandlerType HandlerCHT =
4486e5dd7070Spatrick (QualType)Context.getCanonicalType(H->getCaughtType());
4487e5dd7070Spatrick
4488e5dd7070Spatrick // We can ignore whether the type is a reference or a pointer; we need the
4489e5dd7070Spatrick // underlying declaration type in order to get at the underlying record
4490e5dd7070Spatrick // decl, if there is one.
4491e5dd7070Spatrick QualType Underlying = HandlerCHT.underlying();
4492e5dd7070Spatrick if (auto *RD = Underlying->getAsCXXRecordDecl()) {
4493e5dd7070Spatrick if (!RD->hasDefinition())
4494e5dd7070Spatrick continue;
4495e5dd7070Spatrick // Check that none of the public, unambiguous base classes are in the
4496e5dd7070Spatrick // map ([except.handle]p1). Give the base classes the same pointer
4497e5dd7070Spatrick // qualification as the original type we are basing off of. This allows
4498e5dd7070Spatrick // comparison against the handler type using the same top-level pointer
4499e5dd7070Spatrick // as the original type.
4500e5dd7070Spatrick CXXBasePaths Paths;
4501e5dd7070Spatrick Paths.setOrigin(RD);
4502e5dd7070Spatrick CatchTypePublicBases CTPB(Context, HandledTypes, HandlerCHT.isPointer());
4503e5dd7070Spatrick if (RD->lookupInBases(CTPB, Paths)) {
4504e5dd7070Spatrick const CXXCatchStmt *Problem = CTPB.getFoundHandler();
4505e5dd7070Spatrick if (!Paths.isAmbiguous(CTPB.getFoundHandlerType())) {
4506e5dd7070Spatrick Diag(H->getExceptionDecl()->getTypeSpecStartLoc(),
4507e5dd7070Spatrick diag::warn_exception_caught_by_earlier_handler)
4508e5dd7070Spatrick << H->getCaughtType();
4509e5dd7070Spatrick Diag(Problem->getExceptionDecl()->getTypeSpecStartLoc(),
4510e5dd7070Spatrick diag::note_previous_exception_handler)
4511e5dd7070Spatrick << Problem->getCaughtType();
4512e5dd7070Spatrick }
4513e5dd7070Spatrick }
4514e5dd7070Spatrick }
4515e5dd7070Spatrick
4516e5dd7070Spatrick // Add the type the list of ones we have handled; diagnose if we've already
4517e5dd7070Spatrick // handled it.
4518e5dd7070Spatrick auto R = HandledTypes.insert(std::make_pair(H->getCaughtType(), H));
4519e5dd7070Spatrick if (!R.second) {
4520e5dd7070Spatrick const CXXCatchStmt *Problem = R.first->second;
4521e5dd7070Spatrick Diag(H->getExceptionDecl()->getTypeSpecStartLoc(),
4522e5dd7070Spatrick diag::warn_exception_caught_by_earlier_handler)
4523e5dd7070Spatrick << H->getCaughtType();
4524e5dd7070Spatrick Diag(Problem->getExceptionDecl()->getTypeSpecStartLoc(),
4525e5dd7070Spatrick diag::note_previous_exception_handler)
4526e5dd7070Spatrick << Problem->getCaughtType();
4527e5dd7070Spatrick }
4528e5dd7070Spatrick }
4529e5dd7070Spatrick
4530e5dd7070Spatrick FSI->setHasCXXTry(TryLoc);
4531e5dd7070Spatrick
4532e5dd7070Spatrick return CXXTryStmt::Create(Context, TryLoc, TryBlock, Handlers);
4533e5dd7070Spatrick }
4534e5dd7070Spatrick
ActOnSEHTryBlock(bool IsCXXTry,SourceLocation TryLoc,Stmt * TryBlock,Stmt * Handler)4535e5dd7070Spatrick StmtResult Sema::ActOnSEHTryBlock(bool IsCXXTry, SourceLocation TryLoc,
4536e5dd7070Spatrick Stmt *TryBlock, Stmt *Handler) {
4537e5dd7070Spatrick assert(TryBlock && Handler);
4538e5dd7070Spatrick
4539e5dd7070Spatrick sema::FunctionScopeInfo *FSI = getCurFunction();
4540e5dd7070Spatrick
4541e5dd7070Spatrick // SEH __try is incompatible with C++ try. Borland appears to support this,
4542e5dd7070Spatrick // however.
4543e5dd7070Spatrick if (!getLangOpts().Borland) {
4544*12c85518Srobert if (FSI->FirstCXXOrObjCTryLoc.isValid()) {
4545*12c85518Srobert Diag(TryLoc, diag::err_mixing_cxx_try_seh_try) << FSI->FirstTryType;
4546*12c85518Srobert Diag(FSI->FirstCXXOrObjCTryLoc, diag::note_conflicting_try_here)
4547*12c85518Srobert << (FSI->FirstTryType == sema::FunctionScopeInfo::TryLocIsCXX
4548*12c85518Srobert ? "'try'"
4549*12c85518Srobert : "'@try'");
4550e5dd7070Spatrick }
4551e5dd7070Spatrick }
4552e5dd7070Spatrick
4553e5dd7070Spatrick FSI->setHasSEHTry(TryLoc);
4554e5dd7070Spatrick
4555e5dd7070Spatrick // Reject __try in Obj-C methods, blocks, and captured decls, since we don't
4556e5dd7070Spatrick // track if they use SEH.
4557e5dd7070Spatrick DeclContext *DC = CurContext;
4558e5dd7070Spatrick while (DC && !DC->isFunctionOrMethod())
4559e5dd7070Spatrick DC = DC->getParent();
4560e5dd7070Spatrick FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(DC);
4561e5dd7070Spatrick if (FD)
4562e5dd7070Spatrick FD->setUsesSEHTry(true);
4563e5dd7070Spatrick else
4564e5dd7070Spatrick Diag(TryLoc, diag::err_seh_try_outside_functions);
4565e5dd7070Spatrick
4566e5dd7070Spatrick // Reject __try on unsupported targets.
4567e5dd7070Spatrick if (!Context.getTargetInfo().isSEHTrySupported())
4568e5dd7070Spatrick Diag(TryLoc, diag::err_seh_try_unsupported);
4569e5dd7070Spatrick
4570e5dd7070Spatrick return SEHTryStmt::Create(Context, IsCXXTry, TryLoc, TryBlock, Handler);
4571e5dd7070Spatrick }
4572e5dd7070Spatrick
ActOnSEHExceptBlock(SourceLocation Loc,Expr * FilterExpr,Stmt * Block)4573e5dd7070Spatrick StmtResult Sema::ActOnSEHExceptBlock(SourceLocation Loc, Expr *FilterExpr,
4574e5dd7070Spatrick Stmt *Block) {
4575e5dd7070Spatrick assert(FilterExpr && Block);
4576e5dd7070Spatrick QualType FTy = FilterExpr->getType();
4577e5dd7070Spatrick if (!FTy->isIntegerType() && !FTy->isDependentType()) {
4578e5dd7070Spatrick return StmtError(
4579e5dd7070Spatrick Diag(FilterExpr->getExprLoc(), diag::err_filter_expression_integral)
4580e5dd7070Spatrick << FTy);
4581e5dd7070Spatrick }
4582e5dd7070Spatrick return SEHExceptStmt::Create(Context, Loc, FilterExpr, Block);
4583e5dd7070Spatrick }
4584e5dd7070Spatrick
ActOnStartSEHFinallyBlock()4585e5dd7070Spatrick void Sema::ActOnStartSEHFinallyBlock() {
4586e5dd7070Spatrick CurrentSEHFinally.push_back(CurScope);
4587e5dd7070Spatrick }
4588e5dd7070Spatrick
ActOnAbortSEHFinallyBlock()4589e5dd7070Spatrick void Sema::ActOnAbortSEHFinallyBlock() {
4590e5dd7070Spatrick CurrentSEHFinally.pop_back();
4591e5dd7070Spatrick }
4592e5dd7070Spatrick
ActOnFinishSEHFinallyBlock(SourceLocation Loc,Stmt * Block)4593e5dd7070Spatrick StmtResult Sema::ActOnFinishSEHFinallyBlock(SourceLocation Loc, Stmt *Block) {
4594e5dd7070Spatrick assert(Block);
4595e5dd7070Spatrick CurrentSEHFinally.pop_back();
4596e5dd7070Spatrick return SEHFinallyStmt::Create(Context, Loc, Block);
4597e5dd7070Spatrick }
4598e5dd7070Spatrick
4599e5dd7070Spatrick StmtResult
ActOnSEHLeaveStmt(SourceLocation Loc,Scope * CurScope)4600e5dd7070Spatrick Sema::ActOnSEHLeaveStmt(SourceLocation Loc, Scope *CurScope) {
4601e5dd7070Spatrick Scope *SEHTryParent = CurScope;
4602e5dd7070Spatrick while (SEHTryParent && !SEHTryParent->isSEHTryScope())
4603e5dd7070Spatrick SEHTryParent = SEHTryParent->getParent();
4604e5dd7070Spatrick if (!SEHTryParent)
4605e5dd7070Spatrick return StmtError(Diag(Loc, diag::err_ms___leave_not_in___try));
4606e5dd7070Spatrick CheckJumpOutOfSEHFinally(*this, Loc, *SEHTryParent);
4607e5dd7070Spatrick
4608e5dd7070Spatrick return new (Context) SEHLeaveStmt(Loc);
4609e5dd7070Spatrick }
4610e5dd7070Spatrick
BuildMSDependentExistsStmt(SourceLocation KeywordLoc,bool IsIfExists,NestedNameSpecifierLoc QualifierLoc,DeclarationNameInfo NameInfo,Stmt * Nested)4611e5dd7070Spatrick StmtResult Sema::BuildMSDependentExistsStmt(SourceLocation KeywordLoc,
4612e5dd7070Spatrick bool IsIfExists,
4613e5dd7070Spatrick NestedNameSpecifierLoc QualifierLoc,
4614e5dd7070Spatrick DeclarationNameInfo NameInfo,
4615e5dd7070Spatrick Stmt *Nested)
4616e5dd7070Spatrick {
4617e5dd7070Spatrick return new (Context) MSDependentExistsStmt(KeywordLoc, IsIfExists,
4618e5dd7070Spatrick QualifierLoc, NameInfo,
4619e5dd7070Spatrick cast<CompoundStmt>(Nested));
4620e5dd7070Spatrick }
4621e5dd7070Spatrick
4622e5dd7070Spatrick
ActOnMSDependentExistsStmt(SourceLocation KeywordLoc,bool IsIfExists,CXXScopeSpec & SS,UnqualifiedId & Name,Stmt * Nested)4623e5dd7070Spatrick StmtResult Sema::ActOnMSDependentExistsStmt(SourceLocation KeywordLoc,
4624e5dd7070Spatrick bool IsIfExists,
4625e5dd7070Spatrick CXXScopeSpec &SS,
4626e5dd7070Spatrick UnqualifiedId &Name,
4627e5dd7070Spatrick Stmt *Nested) {
4628e5dd7070Spatrick return BuildMSDependentExistsStmt(KeywordLoc, IsIfExists,
4629e5dd7070Spatrick SS.getWithLocInContext(Context),
4630e5dd7070Spatrick GetNameFromUnqualifiedId(Name),
4631e5dd7070Spatrick Nested);
4632e5dd7070Spatrick }
4633e5dd7070Spatrick
4634e5dd7070Spatrick RecordDecl*
CreateCapturedStmtRecordDecl(CapturedDecl * & CD,SourceLocation Loc,unsigned NumParams)4635e5dd7070Spatrick Sema::CreateCapturedStmtRecordDecl(CapturedDecl *&CD, SourceLocation Loc,
4636e5dd7070Spatrick unsigned NumParams) {
4637e5dd7070Spatrick DeclContext *DC = CurContext;
4638e5dd7070Spatrick while (!(DC->isFunctionOrMethod() || DC->isRecord() || DC->isFileContext()))
4639e5dd7070Spatrick DC = DC->getParent();
4640e5dd7070Spatrick
4641e5dd7070Spatrick RecordDecl *RD = nullptr;
4642e5dd7070Spatrick if (getLangOpts().CPlusPlus)
4643e5dd7070Spatrick RD = CXXRecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc,
4644e5dd7070Spatrick /*Id=*/nullptr);
4645e5dd7070Spatrick else
4646e5dd7070Spatrick RD = RecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc, /*Id=*/nullptr);
4647e5dd7070Spatrick
4648e5dd7070Spatrick RD->setCapturedRecord();
4649e5dd7070Spatrick DC->addDecl(RD);
4650e5dd7070Spatrick RD->setImplicit();
4651e5dd7070Spatrick RD->startDefinition();
4652e5dd7070Spatrick
4653e5dd7070Spatrick assert(NumParams > 0 && "CapturedStmt requires context parameter");
4654e5dd7070Spatrick CD = CapturedDecl::Create(Context, CurContext, NumParams);
4655e5dd7070Spatrick DC->addDecl(CD);
4656e5dd7070Spatrick return RD;
4657e5dd7070Spatrick }
4658e5dd7070Spatrick
4659e5dd7070Spatrick static bool
buildCapturedStmtCaptureList(Sema & S,CapturedRegionScopeInfo * RSI,SmallVectorImpl<CapturedStmt::Capture> & Captures,SmallVectorImpl<Expr * > & CaptureInits)4660e5dd7070Spatrick buildCapturedStmtCaptureList(Sema &S, CapturedRegionScopeInfo *RSI,
4661e5dd7070Spatrick SmallVectorImpl<CapturedStmt::Capture> &Captures,
4662e5dd7070Spatrick SmallVectorImpl<Expr *> &CaptureInits) {
4663e5dd7070Spatrick for (const sema::Capture &Cap : RSI->Captures) {
4664e5dd7070Spatrick if (Cap.isInvalid())
4665e5dd7070Spatrick continue;
4666e5dd7070Spatrick
4667e5dd7070Spatrick // Form the initializer for the capture.
4668e5dd7070Spatrick ExprResult Init = S.BuildCaptureInit(Cap, Cap.getLocation(),
4669e5dd7070Spatrick RSI->CapRegionKind == CR_OpenMP);
4670e5dd7070Spatrick
4671e5dd7070Spatrick // FIXME: Bail out now if the capture is not used and the initializer has
4672e5dd7070Spatrick // no side-effects.
4673e5dd7070Spatrick
4674e5dd7070Spatrick // Create a field for this capture.
4675e5dd7070Spatrick FieldDecl *Field = S.BuildCaptureField(RSI->TheRecordDecl, Cap);
4676e5dd7070Spatrick
4677e5dd7070Spatrick // Add the capture to our list of captures.
4678e5dd7070Spatrick if (Cap.isThisCapture()) {
4679e5dd7070Spatrick Captures.push_back(CapturedStmt::Capture(Cap.getLocation(),
4680e5dd7070Spatrick CapturedStmt::VCK_This));
4681e5dd7070Spatrick } else if (Cap.isVLATypeCapture()) {
4682e5dd7070Spatrick Captures.push_back(
4683e5dd7070Spatrick CapturedStmt::Capture(Cap.getLocation(), CapturedStmt::VCK_VLAType));
4684e5dd7070Spatrick } else {
4685e5dd7070Spatrick assert(Cap.isVariableCapture() && "unknown kind of capture");
4686e5dd7070Spatrick
4687e5dd7070Spatrick if (S.getLangOpts().OpenMP && RSI->CapRegionKind == CR_OpenMP)
4688e5dd7070Spatrick S.setOpenMPCaptureKind(Field, Cap.getVariable(), RSI->OpenMPLevel);
4689e5dd7070Spatrick
4690*12c85518Srobert Captures.push_back(CapturedStmt::Capture(
4691*12c85518Srobert Cap.getLocation(),
4692*12c85518Srobert Cap.isReferenceCapture() ? CapturedStmt::VCK_ByRef
4693e5dd7070Spatrick : CapturedStmt::VCK_ByCopy,
4694*12c85518Srobert cast<VarDecl>(Cap.getVariable())));
4695e5dd7070Spatrick }
4696e5dd7070Spatrick CaptureInits.push_back(Init.get());
4697e5dd7070Spatrick }
4698e5dd7070Spatrick return false;
4699e5dd7070Spatrick }
4700e5dd7070Spatrick
ActOnCapturedRegionStart(SourceLocation Loc,Scope * CurScope,CapturedRegionKind Kind,unsigned NumParams)4701e5dd7070Spatrick void Sema::ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
4702e5dd7070Spatrick CapturedRegionKind Kind,
4703e5dd7070Spatrick unsigned NumParams) {
4704e5dd7070Spatrick CapturedDecl *CD = nullptr;
4705e5dd7070Spatrick RecordDecl *RD = CreateCapturedStmtRecordDecl(CD, Loc, NumParams);
4706e5dd7070Spatrick
4707e5dd7070Spatrick // Build the context parameter
4708e5dd7070Spatrick DeclContext *DC = CapturedDecl::castToDeclContext(CD);
4709e5dd7070Spatrick IdentifierInfo *ParamName = &Context.Idents.get("__context");
4710e5dd7070Spatrick QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD));
4711e5dd7070Spatrick auto *Param =
4712e5dd7070Spatrick ImplicitParamDecl::Create(Context, DC, Loc, ParamName, ParamType,
4713e5dd7070Spatrick ImplicitParamDecl::CapturedContext);
4714e5dd7070Spatrick DC->addDecl(Param);
4715e5dd7070Spatrick
4716e5dd7070Spatrick CD->setContextParam(0, Param);
4717e5dd7070Spatrick
4718e5dd7070Spatrick // Enter the capturing scope for this captured region.
4719e5dd7070Spatrick PushCapturedRegionScope(CurScope, CD, RD, Kind);
4720e5dd7070Spatrick
4721e5dd7070Spatrick if (CurScope)
4722e5dd7070Spatrick PushDeclContext(CurScope, CD);
4723e5dd7070Spatrick else
4724e5dd7070Spatrick CurContext = CD;
4725e5dd7070Spatrick
4726e5dd7070Spatrick PushExpressionEvaluationContext(
4727e5dd7070Spatrick ExpressionEvaluationContext::PotentiallyEvaluated);
4728e5dd7070Spatrick }
4729e5dd7070Spatrick
ActOnCapturedRegionStart(SourceLocation Loc,Scope * CurScope,CapturedRegionKind Kind,ArrayRef<CapturedParamNameType> Params,unsigned OpenMPCaptureLevel)4730e5dd7070Spatrick void Sema::ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
4731e5dd7070Spatrick CapturedRegionKind Kind,
4732e5dd7070Spatrick ArrayRef<CapturedParamNameType> Params,
4733e5dd7070Spatrick unsigned OpenMPCaptureLevel) {
4734e5dd7070Spatrick CapturedDecl *CD = nullptr;
4735e5dd7070Spatrick RecordDecl *RD = CreateCapturedStmtRecordDecl(CD, Loc, Params.size());
4736e5dd7070Spatrick
4737e5dd7070Spatrick // Build the context parameter
4738e5dd7070Spatrick DeclContext *DC = CapturedDecl::castToDeclContext(CD);
4739e5dd7070Spatrick bool ContextIsFound = false;
4740e5dd7070Spatrick unsigned ParamNum = 0;
4741e5dd7070Spatrick for (ArrayRef<CapturedParamNameType>::iterator I = Params.begin(),
4742e5dd7070Spatrick E = Params.end();
4743e5dd7070Spatrick I != E; ++I, ++ParamNum) {
4744e5dd7070Spatrick if (I->second.isNull()) {
4745e5dd7070Spatrick assert(!ContextIsFound &&
4746e5dd7070Spatrick "null type has been found already for '__context' parameter");
4747e5dd7070Spatrick IdentifierInfo *ParamName = &Context.Idents.get("__context");
4748e5dd7070Spatrick QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD))
4749e5dd7070Spatrick .withConst()
4750e5dd7070Spatrick .withRestrict();
4751e5dd7070Spatrick auto *Param =
4752e5dd7070Spatrick ImplicitParamDecl::Create(Context, DC, Loc, ParamName, ParamType,
4753e5dd7070Spatrick ImplicitParamDecl::CapturedContext);
4754e5dd7070Spatrick DC->addDecl(Param);
4755e5dd7070Spatrick CD->setContextParam(ParamNum, Param);
4756e5dd7070Spatrick ContextIsFound = true;
4757e5dd7070Spatrick } else {
4758e5dd7070Spatrick IdentifierInfo *ParamName = &Context.Idents.get(I->first);
4759e5dd7070Spatrick auto *Param =
4760e5dd7070Spatrick ImplicitParamDecl::Create(Context, DC, Loc, ParamName, I->second,
4761e5dd7070Spatrick ImplicitParamDecl::CapturedContext);
4762e5dd7070Spatrick DC->addDecl(Param);
4763e5dd7070Spatrick CD->setParam(ParamNum, Param);
4764e5dd7070Spatrick }
4765e5dd7070Spatrick }
4766e5dd7070Spatrick assert(ContextIsFound && "no null type for '__context' parameter");
4767e5dd7070Spatrick if (!ContextIsFound) {
4768e5dd7070Spatrick // Add __context implicitly if it is not specified.
4769e5dd7070Spatrick IdentifierInfo *ParamName = &Context.Idents.get("__context");
4770e5dd7070Spatrick QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD));
4771e5dd7070Spatrick auto *Param =
4772e5dd7070Spatrick ImplicitParamDecl::Create(Context, DC, Loc, ParamName, ParamType,
4773e5dd7070Spatrick ImplicitParamDecl::CapturedContext);
4774e5dd7070Spatrick DC->addDecl(Param);
4775e5dd7070Spatrick CD->setContextParam(ParamNum, Param);
4776e5dd7070Spatrick }
4777e5dd7070Spatrick // Enter the capturing scope for this captured region.
4778e5dd7070Spatrick PushCapturedRegionScope(CurScope, CD, RD, Kind, OpenMPCaptureLevel);
4779e5dd7070Spatrick
4780e5dd7070Spatrick if (CurScope)
4781e5dd7070Spatrick PushDeclContext(CurScope, CD);
4782e5dd7070Spatrick else
4783e5dd7070Spatrick CurContext = CD;
4784e5dd7070Spatrick
4785e5dd7070Spatrick PushExpressionEvaluationContext(
4786e5dd7070Spatrick ExpressionEvaluationContext::PotentiallyEvaluated);
4787e5dd7070Spatrick }
4788e5dd7070Spatrick
ActOnCapturedRegionError()4789e5dd7070Spatrick void Sema::ActOnCapturedRegionError() {
4790e5dd7070Spatrick DiscardCleanupsInEvaluationContext();
4791e5dd7070Spatrick PopExpressionEvaluationContext();
4792e5dd7070Spatrick PopDeclContext();
4793e5dd7070Spatrick PoppedFunctionScopePtr ScopeRAII = PopFunctionScopeInfo();
4794e5dd7070Spatrick CapturedRegionScopeInfo *RSI = cast<CapturedRegionScopeInfo>(ScopeRAII.get());
4795e5dd7070Spatrick
4796e5dd7070Spatrick RecordDecl *Record = RSI->TheRecordDecl;
4797e5dd7070Spatrick Record->setInvalidDecl();
4798e5dd7070Spatrick
4799e5dd7070Spatrick SmallVector<Decl*, 4> Fields(Record->fields());
4800e5dd7070Spatrick ActOnFields(/*Scope=*/nullptr, Record->getLocation(), Record, Fields,
4801e5dd7070Spatrick SourceLocation(), SourceLocation(), ParsedAttributesView());
4802e5dd7070Spatrick }
4803e5dd7070Spatrick
ActOnCapturedRegionEnd(Stmt * S)4804e5dd7070Spatrick StmtResult Sema::ActOnCapturedRegionEnd(Stmt *S) {
4805e5dd7070Spatrick // Leave the captured scope before we start creating captures in the
4806e5dd7070Spatrick // enclosing scope.
4807e5dd7070Spatrick DiscardCleanupsInEvaluationContext();
4808e5dd7070Spatrick PopExpressionEvaluationContext();
4809e5dd7070Spatrick PopDeclContext();
4810e5dd7070Spatrick PoppedFunctionScopePtr ScopeRAII = PopFunctionScopeInfo();
4811e5dd7070Spatrick CapturedRegionScopeInfo *RSI = cast<CapturedRegionScopeInfo>(ScopeRAII.get());
4812e5dd7070Spatrick
4813e5dd7070Spatrick SmallVector<CapturedStmt::Capture, 4> Captures;
4814e5dd7070Spatrick SmallVector<Expr *, 4> CaptureInits;
4815e5dd7070Spatrick if (buildCapturedStmtCaptureList(*this, RSI, Captures, CaptureInits))
4816e5dd7070Spatrick return StmtError();
4817e5dd7070Spatrick
4818e5dd7070Spatrick CapturedDecl *CD = RSI->TheCapturedDecl;
4819e5dd7070Spatrick RecordDecl *RD = RSI->TheRecordDecl;
4820e5dd7070Spatrick
4821e5dd7070Spatrick CapturedStmt *Res = CapturedStmt::Create(
4822e5dd7070Spatrick getASTContext(), S, static_cast<CapturedRegionKind>(RSI->CapRegionKind),
4823e5dd7070Spatrick Captures, CaptureInits, CD, RD);
4824e5dd7070Spatrick
4825e5dd7070Spatrick CD->setBody(Res->getCapturedStmt());
4826e5dd7070Spatrick RD->completeDefinition();
4827e5dd7070Spatrick
4828e5dd7070Spatrick return Res;
4829e5dd7070Spatrick }
4830