llvm-project

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//===- StmtIterator.cpp - Iterators for Statements ------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file defines internal methods for StmtIterator.
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//
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//===----------------------------------------------------------------------===//
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#include "clang/AST/StmtIterator.h"
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#include "clang/AST/Decl.h"
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#include "clang/AST/Type.h"
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#include "clang/Basic/LLVM.h"
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#include "llvm/Support/Casting.h"
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#include <cassert>
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#include <cstdint>
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using namespace clang;
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// FIXME: Add support for dependent-sized array types in C++?
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// Does it even make sense to build a CFG for an uninstantiated template?
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static inline const VariableArrayType *FindVA(const Type* t) {
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  while (const ArrayType *vt = dyn_cast<ArrayType>(t)) {
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    if (const VariableArrayType *vat = dyn_cast<VariableArrayType>(vt))
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      if (vat->getSizeExpr())
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        return vat;
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    t = vt->getElementType().getTypePtr();
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  }
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  return nullptr;
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}
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void StmtIteratorBase::NextVA() {
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  assert(getVAPtr());
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  const VariableArrayType *p = getVAPtr();
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  p = FindVA(p->getElementType().getTypePtr());
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  setVAPtr(p);
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  if (p)
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    return;
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  if (inDeclGroup()) {
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    if (VarDecl* VD = dyn_cast<VarDecl>(*DGI))
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      if (VD->hasInit())
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        return;
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    NextDecl();
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  }
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  else {
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    assert(inSizeOfTypeVA());
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    RawVAPtr = 0;
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  }
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}
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void StmtIteratorBase::NextDecl(bool ImmediateAdvance) {
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  assert(getVAPtr() == nullptr);
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  assert(inDeclGroup());
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  if (ImmediateAdvance)
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    ++DGI;
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  for ( ; DGI != DGE; ++DGI)
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    if (HandleDecl(*DGI))
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      return;
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  RawVAPtr = 0;
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}
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bool StmtIteratorBase::HandleDecl(Decl* D) {
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  if (VarDecl* VD = dyn_cast<VarDecl>(D)) {
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    if (const VariableArrayType* VAPtr = FindVA(VD->getType().getTypePtr())) {
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      setVAPtr(VAPtr);
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      return true;
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    }
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    if (VD->getInit())
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      return true;
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  }
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  else if (TypedefNameDecl* TD = dyn_cast<TypedefNameDecl>(D)) {
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    if (const VariableArrayType* VAPtr =
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        FindVA(TD->getUnderlyingType().getTypePtr())) {
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      setVAPtr(VAPtr);
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      return true;
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    }
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  }
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  else if (EnumConstantDecl* ECD = dyn_cast<EnumConstantDecl>(D)) {
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    if (ECD->getInitExpr())
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      return true;
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  }
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  return false;
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}
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StmtIteratorBase::StmtIteratorBase(Decl** dgi, Decl** dge)
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    : DGI(dgi), RawVAPtr(DeclGroupMode), DGE(dge) {
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  NextDecl(false);
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}
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StmtIteratorBase::StmtIteratorBase(const VariableArrayType* t)
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    : DGI(nullptr), RawVAPtr(SizeOfTypeVAMode) {
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  RawVAPtr |= reinterpret_cast<uintptr_t>(t);
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}
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Stmt*& StmtIteratorBase::GetDeclExpr() const {
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  if (const VariableArrayType* VAPtr = getVAPtr()) {
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    assert(VAPtr->SizeExpr);
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    return const_cast<Stmt*&>(VAPtr->SizeExpr);
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  }
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  assert(inDeclGroup());
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  VarDecl* VD = cast<VarDecl>(*DGI);
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  return *VD->getInitAddress();
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}
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