Magic-Mirror/llvm-capstone
1
0
Fork 0
mirror of https://github.com/capstone-engine/llvm-capstone.git synced 2024-11-27 15:41:46 +00:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

Avoid allocating extra memory to handle the lazy definition data pointer for

Browse Source 
CXXRecordDecls when modules is enabled.

llvm-svn: 209482
This commit is contained in:
Richard Smith 2014-05-22 23:19:02 +00:00
parent 276d7a1434
commit 64c0630585
4 changed files with 35 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
clang/include/clang/AST/DeclCXX.h
View File

@ -257,10 +257,31 @@ public:
TypeSourceInfo *getTypeSourceInfo() const { return BaseTypeInfo; }
};
/// \brief A lazy pointer to the definition data for a declaration.
/// FIXME: This is a little CXXRecordDecl-specific that the moment.
template<typename Decl, typename T> class LazyDefinitionDataPtr {
llvm::PointerUnion<T *, Decl *> DataOrCanonicalDecl;
LazyDefinitionDataPtr update() {
if (Decl *Canon = DataOrCanonicalDecl.template dyn_cast<Decl*>()) {
if (Canon->isCanonicalDecl())
Canon->getMostRecentDecl();
else
// Declaration isn't canonical any more;
// update it and perform path compression.
*this = Canon->getPreviousDecl()->DefinitionData.update();
}
return *this;
}
public:
LazyDefinitionDataPtr(Decl *Canon) : DataOrCanonicalDecl(Canon) {}
LazyDefinitionDataPtr(T *Data) : DataOrCanonicalDecl(Data) {}
T *getNotUpdated() { return DataOrCanonicalDecl.template dyn_cast<T*>(); }
T *get() { return update().getNotUpdated(); }
};
/// \brief Represents a C++ struct/union/class.
///
/// FIXME: This class will disappear once we've properly taught RecordDecl
/// to deal with C++-specific things.
class CXXRecordDecl : public RecordDecl {
friend void TagDecl::startDefinition();
@ -496,9 +517,9 @@ class CXXRecordDecl : public RecordDecl {
CXXBaseSpecifier *getVBasesSlowCase() const;
};
typedef LazyGenerationalUpdatePtr<const Decl*, struct DefinitionData*,
&ExternalASTSource::CompleteRedeclChain>
typedef LazyDefinitionDataPtr<CXXRecordDecl, struct DefinitionData>
DefinitionDataPtr;
friend class LazyDefinitionDataPtr<CXXRecordDecl, struct DefinitionData>;
mutable DefinitionDataPtr DefinitionData;
@ -558,7 +579,7 @@ class CXXRecordDecl : public RecordDecl {
};
struct DefinitionData &data() const {
auto *DD = DefinitionData.get(this);
auto *DD = DefinitionData.get();
assert(DD && "queried property of class with no definition");
return *DD;
}
@ -643,11 +664,11 @@ public:
}
CXXRecordDecl *getDefinition() const {
auto *DD = DefinitionData.get(this);
auto *DD = DefinitionData.get();
return DD ? DD->Definition : nullptr;
}
bool hasDefinition() const { return DefinitionData.get(this); }
bool hasDefinition() const { return DefinitionData.get(); }
static CXXRecordDecl *Create(const ASTContext &C, TagKind TK, DeclContext *DC,
SourceLocation StartLoc, SourceLocation IdLoc,

2
clang/lib/AST/Decl.cpp
View File

@ -3240,7 +3240,7 @@ void TagDecl::startDefinition() {
struct CXXRecordDecl::DefinitionData *Data =
new (getASTContext()) struct CXXRecordDecl::DefinitionData(D);
for (auto I : redecls())
cast<CXXRecordDecl>(I)->DefinitionData.setNotUpdated(Data);
cast<CXXRecordDecl>(I)->DefinitionData = Data;
}
}

6
clang/lib/AST/DeclCXX.cpp
View File

@ -88,7 +88,7 @@ CXXRecordDecl::CXXRecordDecl(Kind K, TagKind TK, const ASTContext &C,
CXXRecordDecl *PrevDecl)
: RecordDecl(K, TK, C, DC, StartLoc, IdLoc, Id, PrevDecl),
DefinitionData(PrevDecl ? PrevDecl->DefinitionData
: DefinitionDataPtr(C)),
: DefinitionDataPtr(this)),
TemplateOrInstantiation() {}
CXXRecordDecl *CXXRecordDecl::Create(const ASTContext &C, TagKind TK,
@ -115,9 +115,9 @@ CXXRecordDecl::CreateLambda(const ASTContext &C, DeclContext *DC,
new (C, DC) CXXRecordDecl(CXXRecord, TTK_Class, C, DC, Loc, Loc,
nullptr, nullptr);
R->IsBeingDefined = true;
R->DefinitionData.setNotUpdated(
R->DefinitionData =
new (C) struct LambdaDefinitionData(R, Info, Dependent, IsGeneric,
CaptureDefault));
CaptureDefault);
R->MayHaveOutOfDateDef = false;
R->setImplicit(true);
C.getTypeDeclType(R, /*PrevDecl=*/nullptr);

4
clang/lib/Serialization/ASTReaderDecl.cpp
View File

@ -1405,7 +1405,7 @@ void ASTDeclReader::ReadCXXRecordDefinition(CXXRecordDecl *D) {
// that all other deserialized declarations will see it.
CXXRecordDecl *Canon = D->getCanonicalDecl();
if (Canon == D) {
D->DefinitionData.setNotUpdated(DD);
D->DefinitionData = DD;
D->IsCompleteDefinition = true;
} else if (auto *CanonDD = Canon->DefinitionData.getNotUpdated()) {
// We have already deserialized a definition of this record. This
@ -1417,7 +1417,7 @@ void ASTDeclReader::ReadCXXRecordDefinition(CXXRecordDecl *D) {
D->IsCompleteDefinition = false;
MergeDefinitionData(D, *DD);
} else {
Canon->DefinitionData.setNotUpdated(DD);
Canon->DefinitionData = DD;
D->DefinitionData = Canon->DefinitionData;
D->IsCompleteDefinition = true;