92 lines · cpp
1//===--- CFGStmtMap.h - Map from Stmt* to CFGBlock* -----------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file defines the CFGStmtMap class, which defines a mapping from10// Stmt* to CFGBlock*11//12//===----------------------------------------------------------------------===//13 14#include "llvm/ADT/DenseMap.h"15#include "clang/AST/ParentMap.h"16#include "clang/Analysis/CFG.h"17#include "clang/Analysis/CFGStmtMap.h"18#include <optional>19 20using namespace clang;21 22typedef llvm::DenseMap<const Stmt*, CFGBlock*> SMap;23static SMap *AsMap(void *m) { return (SMap*) m; }24 25CFGStmtMap::~CFGStmtMap() { delete AsMap(M); }26 27CFGBlock *CFGStmtMap::getBlock(Stmt *S) {28 SMap *SM = AsMap(M);29 Stmt *X = S;30 31 // If 'S' isn't in the map, walk the ParentMap to see if one of its ancestors32 // is in the map.33 while (X) {34 SMap::iterator I = SM->find(X);35 if (I != SM->end()) {36 CFGBlock *B = I->second;37 // Memoize this lookup.38 if (X != S)39 (*SM)[X] = B;40 return B;41 }42 43 X = PM->getParentIgnoreParens(X);44 }45 46 return nullptr;47}48 49static void Accumulate(SMap &SM, CFGBlock *B) {50 // First walk the block-level expressions.51 for (CFGBlock::iterator I = B->begin(), E = B->end(); I != E; ++I) {52 const CFGElement &CE = *I;53 std::optional<CFGStmt> CS = CE.getAs<CFGStmt>();54 if (!CS)55 continue;56 57 CFGBlock *&Entry = SM[CS->getStmt()];58 // If 'Entry' is already initialized (e.g., a terminator was already),59 // skip.60 if (Entry)61 continue;62 63 Entry = B;64 65 }66 67 // Look at the label of the block.68 if (Stmt *Label = B->getLabel())69 SM[Label] = B;70 71 // Finally, look at the terminator. If the terminator was already added72 // because it is a block-level expression in another block, overwrite73 // that mapping.74 if (Stmt *Term = B->getTerminatorStmt())75 SM[Term] = B;76}77 78CFGStmtMap *CFGStmtMap::Build(CFG *C, ParentMap *PM) {79 if (!C || !PM)80 return nullptr;81 82 SMap *SM = new SMap();83 84 // Walk all blocks, accumulating the block-level expressions, labels,85 // and terminators.86 for (CFGBlock *BB : *C)87 Accumulate(*SM, BB);88 89 return new CFGStmtMap(PM, SM);90}91 92