1*7330f729Sjoerg //===--- CFGStmtMap.h - Map from Stmt* to CFGBlock* -----------*- C++ -*-===//
2*7330f729Sjoerg //
3*7330f729Sjoerg // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*7330f729Sjoerg // See https://llvm.org/LICENSE.txt for license information.
5*7330f729Sjoerg // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*7330f729Sjoerg //
7*7330f729Sjoerg //===----------------------------------------------------------------------===//
8*7330f729Sjoerg //
9*7330f729Sjoerg // This file defines the CFGStmtMap class, which defines a mapping from
10*7330f729Sjoerg // Stmt* to CFGBlock*
11*7330f729Sjoerg //
12*7330f729Sjoerg //===----------------------------------------------------------------------===//
13*7330f729Sjoerg
14*7330f729Sjoerg #include "llvm/ADT/DenseMap.h"
15*7330f729Sjoerg #include "clang/AST/ParentMap.h"
16*7330f729Sjoerg #include "clang/Analysis/CFG.h"
17*7330f729Sjoerg #include "clang/Analysis/CFGStmtMap.h"
18*7330f729Sjoerg
19*7330f729Sjoerg using namespace clang;
20*7330f729Sjoerg
21*7330f729Sjoerg typedef llvm::DenseMap<const Stmt*, CFGBlock*> SMap;
AsMap(void * m)22*7330f729Sjoerg static SMap *AsMap(void *m) { return (SMap*) m; }
23*7330f729Sjoerg
~CFGStmtMap()24*7330f729Sjoerg CFGStmtMap::~CFGStmtMap() { delete AsMap(M); }
25*7330f729Sjoerg
getBlock(Stmt * S)26*7330f729Sjoerg CFGBlock *CFGStmtMap::getBlock(Stmt *S) {
27*7330f729Sjoerg SMap *SM = AsMap(M);
28*7330f729Sjoerg Stmt *X = S;
29*7330f729Sjoerg
30*7330f729Sjoerg // If 'S' isn't in the map, walk the ParentMap to see if one of its ancestors
31*7330f729Sjoerg // is in the map.
32*7330f729Sjoerg while (X) {
33*7330f729Sjoerg SMap::iterator I = SM->find(X);
34*7330f729Sjoerg if (I != SM->end()) {
35*7330f729Sjoerg CFGBlock *B = I->second;
36*7330f729Sjoerg // Memoize this lookup.
37*7330f729Sjoerg if (X != S)
38*7330f729Sjoerg (*SM)[X] = B;
39*7330f729Sjoerg return B;
40*7330f729Sjoerg }
41*7330f729Sjoerg
42*7330f729Sjoerg X = PM->getParentIgnoreParens(X);
43*7330f729Sjoerg }
44*7330f729Sjoerg
45*7330f729Sjoerg return nullptr;
46*7330f729Sjoerg }
47*7330f729Sjoerg
Accumulate(SMap & SM,CFGBlock * B)48*7330f729Sjoerg static void Accumulate(SMap &SM, CFGBlock *B) {
49*7330f729Sjoerg // First walk the block-level expressions.
50*7330f729Sjoerg for (CFGBlock::iterator I = B->begin(), E = B->end(); I != E; ++I) {
51*7330f729Sjoerg const CFGElement &CE = *I;
52*7330f729Sjoerg Optional<CFGStmt> CS = CE.getAs<CFGStmt>();
53*7330f729Sjoerg if (!CS)
54*7330f729Sjoerg continue;
55*7330f729Sjoerg
56*7330f729Sjoerg CFGBlock *&Entry = SM[CS->getStmt()];
57*7330f729Sjoerg // If 'Entry' is already initialized (e.g., a terminator was already),
58*7330f729Sjoerg // skip.
59*7330f729Sjoerg if (Entry)
60*7330f729Sjoerg continue;
61*7330f729Sjoerg
62*7330f729Sjoerg Entry = B;
63*7330f729Sjoerg
64*7330f729Sjoerg }
65*7330f729Sjoerg
66*7330f729Sjoerg // Look at the label of the block.
67*7330f729Sjoerg if (Stmt *Label = B->getLabel())
68*7330f729Sjoerg SM[Label] = B;
69*7330f729Sjoerg
70*7330f729Sjoerg // Finally, look at the terminator. If the terminator was already added
71*7330f729Sjoerg // because it is a block-level expression in another block, overwrite
72*7330f729Sjoerg // that mapping.
73*7330f729Sjoerg if (Stmt *Term = B->getTerminatorStmt())
74*7330f729Sjoerg SM[Term] = B;
75*7330f729Sjoerg }
76*7330f729Sjoerg
Build(CFG * C,ParentMap * PM)77*7330f729Sjoerg CFGStmtMap *CFGStmtMap::Build(CFG *C, ParentMap *PM) {
78*7330f729Sjoerg if (!C || !PM)
79*7330f729Sjoerg return nullptr;
80*7330f729Sjoerg
81*7330f729Sjoerg SMap *SM = new SMap();
82*7330f729Sjoerg
83*7330f729Sjoerg // Walk all blocks, accumulating the block-level expressions, labels,
84*7330f729Sjoerg // and terminators.
85*7330f729Sjoerg for (CFG::iterator I = C->begin(), E = C->end(); I != E; ++I)
86*7330f729Sjoerg Accumulate(*SM, *I);
87*7330f729Sjoerg
88*7330f729Sjoerg return new CFGStmtMap(PM, SM);
89*7330f729Sjoerg }
90*7330f729Sjoerg
91