llvm-project/clang/lib/Sema/IdentifierResolver.cpp

274 lines
9.0 KiB
C++

//===- IdentifierResolver.cpp - Lexical Scope Name lookup -------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the IdentifierResolver class, which is used for lexical
// scoped lookup, based on declaration names.
//
//===----------------------------------------------------------------------===//
#include "IdentifierResolver.h"
#include "clang/Basic/LangOptions.h"
#include <list>
#include <vector>
using namespace clang;
//===----------------------------------------------------------------------===//
// IdDeclInfoMap class
//===----------------------------------------------------------------------===//
/// IdDeclInfoMap - Associates IdDeclInfos with declaration names.
/// Allocates 'pools' (vectors of IdDeclInfos) to avoid allocating each
/// individual IdDeclInfo to heap.
class IdentifierResolver::IdDeclInfoMap {
static const unsigned int VECTOR_SIZE = 512;
// Holds vectors of IdDeclInfos that serve as 'pools'.
// New vectors are added when the current one is full.
std::list< std::vector<IdDeclInfo> > IDIVecs;
unsigned int CurIndex;
public:
IdDeclInfoMap() : CurIndex(VECTOR_SIZE) {}
/// Returns the IdDeclInfo associated to the DeclarationName.
/// It creates a new IdDeclInfo if one was not created before for this id.
IdDeclInfo &operator[](DeclarationName Name);
};
//===----------------------------------------------------------------------===//
// LookupContext Implementation
//===----------------------------------------------------------------------===//
/// getContext - Returns translation unit context for non Decls and
/// for EnumConstantDecls returns the parent context of their EnumDecl.
DeclContext *IdentifierResolver::LookupContext::getContext(Decl *D) {
DeclContext *Ctx = D->getDeclContext();
if (!Ctx) // FIXME: HACK! We shouldn't end up with a NULL context here.
return TUCtx();
Ctx = Ctx->getLookupContext();
if (isa<TranslationUnitDecl>(Ctx))
return TUCtx();
return Ctx;
}
/// isEqOrContainedBy - Returns true of the given context is the same or a
/// parent of this one.
bool IdentifierResolver::LookupContext::isEqOrContainedBy(
const LookupContext &PC) const {
if (PC.isTU()) return true;
for (LookupContext Next = *this; !Next.isTU(); Next = Next.getParent())
if (Next.Ctx == PC.Ctx) return true;
return false;
}
//===----------------------------------------------------------------------===//
// IdDeclInfo Implementation
//===----------------------------------------------------------------------===//
/// AddShadowed - Add a decl by putting it directly above the 'Shadow' decl.
/// Later lookups will find the 'Shadow' decl first. The 'Shadow' decl must
/// be already added to the scope chain and must be in the same context as
/// the decl that we want to add.
void IdentifierResolver::IdDeclInfo::AddShadowed(NamedDecl *D,
NamedDecl *Shadow) {
for (DeclsTy::iterator I = Decls.end(); I != Decls.begin(); --I) {
if (Shadow == *(I-1)) {
Decls.insert(I-1, D);
return;
}
}
assert(0 && "Shadow wasn't in scope chain!");
}
/// RemoveDecl - Remove the decl from the scope chain.
/// The decl must already be part of the decl chain.
void IdentifierResolver::IdDeclInfo::RemoveDecl(NamedDecl *D) {
for (DeclsTy::iterator I = Decls.end(); I != Decls.begin(); --I) {
if (D == *(I-1)) {
Decls.erase(I-1);
return;
}
}
assert(0 && "Didn't find this decl on its identifier's chain!");
}
//===----------------------------------------------------------------------===//
// IdentifierResolver Implementation
//===----------------------------------------------------------------------===//
IdentifierResolver::IdentifierResolver(const LangOptions &langOpt)
: LangOpt(langOpt), IdDeclInfos(new IdDeclInfoMap) {
}
IdentifierResolver::~IdentifierResolver() {
delete IdDeclInfos;
}
/// isDeclInScope - If 'Ctx' is a function/method, isDeclInScope returns true
/// if 'D' is in Scope 'S', otherwise 'S' is ignored and isDeclInScope returns
/// true if 'D' belongs to the given declaration context.
bool IdentifierResolver::isDeclInScope(Decl *D, DeclContext *Ctx,
ASTContext &Context, Scope *S) const {
Ctx = Ctx->getLookupContext();
if (Ctx->isFunctionOrMethod()) {
// Ignore the scopes associated within transparent declaration contexts.
while (S->getEntity() &&
((DeclContext *)S->getEntity())->isTransparentContext())
S = S->getParent();
if (S->isDeclScope(D))
return true;
if (LangOpt.CPlusPlus) {
// C++ 3.3.2p3:
// The name declared in a catch exception-declaration is local to the
// handler and shall not be redeclared in the outermost block of the
// handler.
// C++ 3.3.2p4:
// Names declared in the for-init-statement, and in the condition of if,
// while, for, and switch statements are local to the if, while, for, or
// switch statement (including the controlled statement), and shall not be
// redeclared in a subsequent condition of that statement nor in the
// outermost block (or, for the if statement, any of the outermost blocks)
// of the controlled statement.
//
assert(S->getParent() && "No TUScope?");
if (S->getParent()->getFlags() & Scope::ControlScope)
return S->getParent()->isDeclScope(D);
}
return false;
}
return LookupContext(D) == LookupContext(Ctx->getPrimaryContext());
}
/// AddDecl - Link the decl to its shadowed decl chain.
void IdentifierResolver::AddDecl(NamedDecl *D) {
DeclarationName Name = D->getDeclName();
void *Ptr = Name.getFETokenInfo<void>();
if (!Ptr) {
Name.setFETokenInfo(D);
return;
}
IdDeclInfo *IDI;
if (isDeclPtr(Ptr)) {
Name.setFETokenInfo(NULL);
IDI = &(*IdDeclInfos)[Name];
NamedDecl *PrevD = static_cast<NamedDecl*>(Ptr);
IDI->AddDecl(PrevD);
} else
IDI = toIdDeclInfo(Ptr);
IDI->AddDecl(D);
}
/// AddShadowedDecl - Link the decl to its shadowed decl chain putting it
/// after the decl that the iterator points to, thus the 'Shadow' decl will be
/// encountered before the 'D' decl.
void IdentifierResolver::AddShadowedDecl(NamedDecl *D, NamedDecl *Shadow) {
assert(D->getDeclName() == Shadow->getDeclName() && "Different ids!");
DeclarationName Name = D->getDeclName();
void *Ptr = Name.getFETokenInfo<void>();
assert(Ptr && "No decl from Ptr ?");
IdDeclInfo *IDI;
if (isDeclPtr(Ptr)) {
Name.setFETokenInfo(NULL);
IDI = &(*IdDeclInfos)[Name];
NamedDecl *PrevD = static_cast<NamedDecl*>(Ptr);
assert(PrevD == Shadow && "Invalid shadow decl ?");
IDI->AddDecl(D);
IDI->AddDecl(PrevD);
return;
}
IDI = toIdDeclInfo(Ptr);
IDI->AddShadowed(D, Shadow);
}
/// RemoveDecl - Unlink the decl from its shadowed decl chain.
/// The decl must already be part of the decl chain.
void IdentifierResolver::RemoveDecl(NamedDecl *D) {
assert(D && "null param passed");
DeclarationName Name = D->getDeclName();
void *Ptr = Name.getFETokenInfo<void>();
assert(Ptr && "Didn't find this decl on its identifier's chain!");
if (isDeclPtr(Ptr)) {
assert(D == Ptr && "Didn't find this decl on its identifier's chain!");
Name.setFETokenInfo(NULL);
return;
}
return toIdDeclInfo(Ptr)->RemoveDecl(D);
}
/// begin - Returns an iterator for decls with name 'Name'.
IdentifierResolver::iterator
IdentifierResolver::begin(DeclarationName Name) {
void *Ptr = Name.getFETokenInfo<void>();
if (!Ptr) return end();
if (isDeclPtr(Ptr)) {
NamedDecl *D = static_cast<NamedDecl*>(Ptr);
return iterator(D);
}
IdDeclInfo *IDI = toIdDeclInfo(Ptr);
IdDeclInfo::DeclsTy::iterator I = IDI->decls_end();
if (I != IDI->decls_begin())
return iterator(I-1);
else // No decls found.
return end();
}
//===----------------------------------------------------------------------===//
// IdDeclInfoMap Implementation
//===----------------------------------------------------------------------===//
/// Returns the IdDeclInfo associated to the DeclarationName.
/// It creates a new IdDeclInfo if one was not created before for this id.
IdentifierResolver::IdDeclInfo &
IdentifierResolver::IdDeclInfoMap::operator[](DeclarationName Name) {
void *Ptr = Name.getFETokenInfo<void>();
if (Ptr) return *toIdDeclInfo(Ptr);
if (CurIndex == VECTOR_SIZE) {
// Add a IdDeclInfo vector 'pool'
IDIVecs.push_back(std::vector<IdDeclInfo>());
// Fill the vector
IDIVecs.back().resize(VECTOR_SIZE);
CurIndex = 0;
}
IdDeclInfo *IDI = &IDIVecs.back()[CurIndex];
Name.setFETokenInfo(reinterpret_cast<void*>(
reinterpret_cast<uintptr_t>(IDI) | 0x1)
);
++CurIndex;
return *IDI;
}