1*0b57cec5SDimitry Andric //===--- TransUnusedInitDelegate.cpp - Transformations to ARC mode --------===//
2*0b57cec5SDimitry Andric //
3*0b57cec5SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*0b57cec5SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
5*0b57cec5SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*0b57cec5SDimitry Andric //
7*0b57cec5SDimitry Andric //===----------------------------------------------------------------------===//
8*0b57cec5SDimitry Andric // Transformations:
9*0b57cec5SDimitry Andric //===----------------------------------------------------------------------===//
10*0b57cec5SDimitry Andric //
11*0b57cec5SDimitry Andric // rewriteUnusedInitDelegate:
12*0b57cec5SDimitry Andric //
13*0b57cec5SDimitry Andric // Rewrites an unused result of calling a delegate initialization, to assigning
14*0b57cec5SDimitry Andric // the result to self.
15*0b57cec5SDimitry Andric // e.g
16*0b57cec5SDimitry Andric // [self init];
17*0b57cec5SDimitry Andric // ---->
18*0b57cec5SDimitry Andric // self = [self init];
19*0b57cec5SDimitry Andric //
20*0b57cec5SDimitry Andric //===----------------------------------------------------------------------===//
21*0b57cec5SDimitry Andric
22*0b57cec5SDimitry Andric #include "Transforms.h"
23*0b57cec5SDimitry Andric #include "Internals.h"
24*0b57cec5SDimitry Andric #include "clang/AST/ASTContext.h"
25*0b57cec5SDimitry Andric #include "clang/Sema/SemaDiagnostic.h"
26*0b57cec5SDimitry Andric
27*0b57cec5SDimitry Andric using namespace clang;
28*0b57cec5SDimitry Andric using namespace arcmt;
29*0b57cec5SDimitry Andric using namespace trans;
30*0b57cec5SDimitry Andric
31*0b57cec5SDimitry Andric namespace {
32*0b57cec5SDimitry Andric
33*0b57cec5SDimitry Andric class UnusedInitRewriter : public RecursiveASTVisitor<UnusedInitRewriter> {
34*0b57cec5SDimitry Andric Stmt *Body;
35*0b57cec5SDimitry Andric MigrationPass &Pass;
36*0b57cec5SDimitry Andric
37*0b57cec5SDimitry Andric ExprSet Removables;
38*0b57cec5SDimitry Andric
39*0b57cec5SDimitry Andric public:
UnusedInitRewriter(MigrationPass & pass)40*0b57cec5SDimitry Andric UnusedInitRewriter(MigrationPass &pass)
41*0b57cec5SDimitry Andric : Body(nullptr), Pass(pass) { }
42*0b57cec5SDimitry Andric
transformBody(Stmt * body,Decl * ParentD)43*0b57cec5SDimitry Andric void transformBody(Stmt *body, Decl *ParentD) {
44*0b57cec5SDimitry Andric Body = body;
45*0b57cec5SDimitry Andric collectRemovables(body, Removables);
46*0b57cec5SDimitry Andric TraverseStmt(body);
47*0b57cec5SDimitry Andric }
48*0b57cec5SDimitry Andric
VisitObjCMessageExpr(ObjCMessageExpr * ME)49*0b57cec5SDimitry Andric bool VisitObjCMessageExpr(ObjCMessageExpr *ME) {
50*0b57cec5SDimitry Andric if (ME->isDelegateInitCall() &&
51*0b57cec5SDimitry Andric isRemovable(ME) &&
52*0b57cec5SDimitry Andric Pass.TA.hasDiagnostic(diag::err_arc_unused_init_message,
53*0b57cec5SDimitry Andric ME->getExprLoc())) {
54*0b57cec5SDimitry Andric Transaction Trans(Pass.TA);
55*0b57cec5SDimitry Andric Pass.TA.clearDiagnostic(diag::err_arc_unused_init_message,
56*0b57cec5SDimitry Andric ME->getExprLoc());
57*0b57cec5SDimitry Andric SourceRange ExprRange = ME->getSourceRange();
58*0b57cec5SDimitry Andric Pass.TA.insert(ExprRange.getBegin(), "if (!(self = ");
59*0b57cec5SDimitry Andric std::string retStr = ")) return ";
60*0b57cec5SDimitry Andric retStr += getNilString(Pass);
61*0b57cec5SDimitry Andric Pass.TA.insertAfterToken(ExprRange.getEnd(), retStr);
62*0b57cec5SDimitry Andric }
63*0b57cec5SDimitry Andric return true;
64*0b57cec5SDimitry Andric }
65*0b57cec5SDimitry Andric
66*0b57cec5SDimitry Andric private:
isRemovable(Expr * E) const67*0b57cec5SDimitry Andric bool isRemovable(Expr *E) const {
68*0b57cec5SDimitry Andric return Removables.count(E);
69*0b57cec5SDimitry Andric }
70*0b57cec5SDimitry Andric };
71*0b57cec5SDimitry Andric
72*0b57cec5SDimitry Andric } // anonymous namespace
73*0b57cec5SDimitry Andric
rewriteUnusedInitDelegate(MigrationPass & pass)74*0b57cec5SDimitry Andric void trans::rewriteUnusedInitDelegate(MigrationPass &pass) {
75*0b57cec5SDimitry Andric BodyTransform<UnusedInitRewriter> trans(pass);
76*0b57cec5SDimitry Andric trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl());
77*0b57cec5SDimitry Andric }
78