gecko-dev/build/clang-plugin/StmtToBlockMap.h

91 строка
2.9 KiB
C++

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef StmtToBlockMap_h__
#define StmtToBlockMap_h__
#include "Utils.h"
// This method is copied from clang-tidy's ExprSequence.cpp.
//
// Returns the Stmt nodes that are parents of 'S', skipping any potential
// intermediate non-Stmt nodes.
//
// In almost all cases, this function returns a single parent or no parents at
// all.
inline SmallVector<const Stmt *, 1> getParentStmts(const Stmt *S,
ASTContext *Context) {
SmallVector<const Stmt *, 1> Result;
auto Parents = Context->getParents(*S);
SmallVector<clang::DynTypedNode, 1> NodesToProcess(Parents.begin(),
Parents.end());
while (!NodesToProcess.empty()) {
clang::DynTypedNode Node = NodesToProcess.back();
NodesToProcess.pop_back();
if (const auto *S = Node.get<Stmt>()) {
Result.push_back(S);
} else {
Parents = Context->getParents(Node);
NodesToProcess.append(Parents.begin(), Parents.end());
}
}
return Result;
}
// This class is a modified version of the class from clang-tidy's
// ExprSequence.cpp
//
// Maps `Stmt`s to the `CFGBlock` that contains them. Some `Stmt`s may be
// contained in more than one `CFGBlock`; in this case, they are mapped to the
// innermost block (i.e. the one that is furthest from the root of the tree).
// An optional outparameter provides the index into the block where the `Stmt`
// was found.
class StmtToBlockMap {
public:
// Initializes the map for the given `CFG`.
StmtToBlockMap(const CFG *TheCFG, ASTContext *TheContext)
: Context(TheContext) {
for (const auto *B : *TheCFG) {
for (size_t I = 0; I < B->size(); ++I) {
if (auto S = (*B)[I].getAs<CFGStmt>()) {
Map[S->getStmt()] = std::make_pair(B, I);
}
}
}
}
// Returns the block that S is contained in. Some `Stmt`s may be contained
// in more than one `CFGBlock`; in this case, this function returns the
// innermost block (i.e. the one that is furthest from the root of the tree).
//
// The optional outparameter `Index` is set to the index into the block where
// the `Stmt` was found.
const CFGBlock *blockContainingStmt(const Stmt *S,
size_t *Index = nullptr) const {
while (!Map.count(S)) {
SmallVector<const Stmt *, 1> Parents = getParentStmts(S, Context);
if (Parents.empty())
return nullptr;
S = Parents[0];
}
const auto &E = Map.lookup(S);
if (Index)
*Index = E.second;
return E.first;
}
private:
ASTContext *Context;
llvm::DenseMap<const Stmt *, std::pair<const CFGBlock *, size_t>> Map;
};
#endif // StmtToBlockMap_h__