Refactor the construction of nested-name-specifiers with
source-location information into a NestedNameSpecifierLocBuilder
class, which lives within the AST library and centralize all knowledge
of the format of nested-name-specifier location information here.
No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@126716 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/NestedNameSpecifier.cpp b/lib/AST/NestedNameSpecifier.cpp
index 6f1ec05..2878dff 100644
--- a/lib/AST/NestedNameSpecifier.cpp
+++ b/lib/AST/NestedNameSpecifier.cpp
@@ -371,3 +371,249 @@
void *TypeData = LoadPointer(Data, Offset);
return TypeLoc(Qualifier->getAsType(), TypeData);
}
+
+namespace {
+ void Append(char *Start, char *End, char *&Buffer, unsigned &BufferSize,
+ unsigned &BufferCapacity) {
+ if (BufferSize + (End - Start) > BufferCapacity) {
+ // Reallocate the buffer.
+ unsigned NewCapacity
+ = std::max((unsigned)(BufferCapacity? BufferCapacity * 2
+ : sizeof(void*) * 2),
+ (unsigned)(BufferSize + (End - Start)));
+ char *NewBuffer = static_cast<char *>(malloc(NewCapacity));
+ memcpy(NewBuffer, Buffer, BufferSize);
+
+ if (BufferCapacity)
+ free(Buffer);
+ Buffer = NewBuffer;
+ BufferCapacity = NewCapacity;
+ }
+
+ memcpy(Buffer + BufferSize, Start, End - Start);
+ BufferSize += End-Start;
+ }
+
+ /// \brief Save a source location to the given buffer.
+ void SaveSourceLocation(SourceLocation Loc, char *&Buffer,
+ unsigned &BufferSize, unsigned &BufferCapacity) {
+ unsigned Raw = Loc.getRawEncoding();
+ Append(reinterpret_cast<char *>(&Raw),
+ reinterpret_cast<char *>(&Raw) + sizeof(unsigned),
+ Buffer, BufferSize, BufferCapacity);
+ }
+
+ /// \brief Save a pointer to the given buffer.
+ void SavePointer(void *Ptr, char *&Buffer, unsigned &BufferSize,
+ unsigned &BufferCapacity) {
+ Append(reinterpret_cast<char *>(&Ptr),
+ reinterpret_cast<char *>(&Ptr) + sizeof(void *),
+ Buffer, BufferSize, BufferCapacity);
+ }
+}
+
+NestedNameSpecifierLocBuilder::NestedNameSpecifierLocBuilder()
+ : Representation(0), Buffer(0), BufferSize(0), BufferCapacity(0) { }
+
+NestedNameSpecifierLocBuilder::
+NestedNameSpecifierLocBuilder(const NestedNameSpecifierLocBuilder &Other)
+ : Representation(Other.Representation), Buffer(0),
+ BufferSize(0), BufferCapacity(0)
+{
+ if (!Other.Buffer)
+ return;
+
+ if (Other.BufferCapacity == 0) {
+ // Shallow copy is okay.
+ Buffer = Other.Buffer;
+ BufferSize = Other.BufferSize;
+ return;
+ }
+
+ // Deep copy
+ BufferSize = Other.BufferSize;
+ BufferCapacity = Other.BufferSize;
+ Buffer = static_cast<char *>(malloc(BufferCapacity));
+ memcpy(Buffer, Other.Buffer, BufferSize);
+}
+
+NestedNameSpecifierLocBuilder &
+NestedNameSpecifierLocBuilder::
+operator=(const NestedNameSpecifierLocBuilder &Other) {
+ Representation = Other.Representation;
+
+ if (Buffer && Other.Buffer && BufferCapacity >= Other.BufferSize) {
+ // Re-use our storage.
+ BufferSize = Other.BufferSize;
+ memcpy(Buffer, Other.Buffer, BufferSize);
+ return *this;
+ }
+
+ // Free our storage, if we have any.
+ if (BufferCapacity) {
+ free(Buffer);
+ BufferCapacity = 0;
+ }
+
+ if (!Other.Buffer) {
+ // Empty.
+ Buffer = 0;
+ BufferSize = 0;
+ return *this;
+ }
+
+ if (Other.BufferCapacity == 0) {
+ // Shallow copy is okay.
+ Buffer = Other.Buffer;
+ BufferSize = Other.BufferSize;
+ return *this;
+ }
+
+ // Deep copy.
+ BufferSize = Other.BufferSize;
+ BufferCapacity = BufferSize;
+ Buffer = static_cast<char *>(malloc(BufferSize));
+ memcpy(Buffer, Other.Buffer, BufferSize);
+ return *this;
+}
+
+NestedNameSpecifierLocBuilder::~NestedNameSpecifierLocBuilder() {
+ if (BufferCapacity)
+ free(Buffer);
+}
+
+void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
+ SourceLocation TemplateKWLoc,
+ TypeLoc TL,
+ SourceLocation ColonColonLoc) {
+ Representation = NestedNameSpecifier::Create(Context, Representation,
+ TemplateKWLoc.isValid(),
+ TL.getTypePtr());
+
+ // Push source-location info into the buffer.
+ SavePointer(TL.getOpaqueData(), Buffer, BufferSize, BufferCapacity);
+ SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
+}
+
+void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
+ IdentifierInfo *Identifier,
+ SourceLocation IdentifierLoc,
+ SourceLocation ColonColonLoc) {
+ Representation = NestedNameSpecifier::Create(Context, Representation,
+ Identifier);
+
+ // Push source-location info into the buffer.
+ SaveSourceLocation(IdentifierLoc, Buffer, BufferSize, BufferCapacity);
+ SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
+}
+
+void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
+ NamespaceDecl *Namespace,
+ SourceLocation NamespaceLoc,
+ SourceLocation ColonColonLoc) {
+ Representation = NestedNameSpecifier::Create(Context, Representation,
+ Namespace);
+
+ // Push source-location info into the buffer.
+ SaveSourceLocation(NamespaceLoc, Buffer, BufferSize, BufferCapacity);
+ SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
+}
+
+void NestedNameSpecifierLocBuilder::Extend(ASTContext &Context,
+ NamespaceAliasDecl *Alias,
+ SourceLocation AliasLoc,
+ SourceLocation ColonColonLoc) {
+ Representation = NestedNameSpecifier::Create(Context, Representation, Alias);
+
+ // Push source-location info into the buffer.
+ SaveSourceLocation(AliasLoc, Buffer, BufferSize, BufferCapacity);
+ SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
+}
+
+void NestedNameSpecifierLocBuilder::MakeGlobal(ASTContext &Context,
+ SourceLocation ColonColonLoc) {
+ assert(!Representation && "Already have a nested-name-specifier!?");
+ Representation = NestedNameSpecifier::GlobalSpecifier(Context);
+
+ // Push source-location info into the buffer.
+ SaveSourceLocation(ColonColonLoc, Buffer, BufferSize, BufferCapacity);
+}
+
+void NestedNameSpecifierLocBuilder::MakeTrivial(ASTContext &Context,
+ NestedNameSpecifier *Qualifier,
+ SourceRange R) {
+ Representation = Qualifier;
+
+ // Construct bogus (but well-formed) source information for the
+ // nested-name-specifier.
+ BufferSize = 0;
+ llvm::SmallVector<NestedNameSpecifier *, 4> Stack;
+ for (NestedNameSpecifier *NNS = Qualifier; NNS; NNS = NNS->getPrefix())
+ Stack.push_back(NNS);
+ while (!Stack.empty()) {
+ NestedNameSpecifier *NNS = Stack.back();
+ Stack.pop_back();
+ switch (NNS->getKind()) {
+ case NestedNameSpecifier::Identifier:
+ case NestedNameSpecifier::Namespace:
+ case NestedNameSpecifier::NamespaceAlias:
+ SaveSourceLocation(R.getBegin(), Buffer, BufferSize, BufferCapacity);
+ break;
+
+ case NestedNameSpecifier::TypeSpec:
+ case NestedNameSpecifier::TypeSpecWithTemplate: {
+ TypeSourceInfo *TSInfo
+ = Context.getTrivialTypeSourceInfo(QualType(NNS->getAsType(), 0),
+ R.getBegin());
+ SavePointer(TSInfo->getTypeLoc().getOpaqueData(), Buffer, BufferSize,
+ BufferCapacity);
+ break;
+ }
+
+ case NestedNameSpecifier::Global:
+ break;
+ }
+
+ // Save the location of the '::'.
+ SaveSourceLocation(Stack.empty()? R.getEnd() : R.getBegin(),
+ Buffer, BufferSize, BufferCapacity);
+ }
+}
+
+void NestedNameSpecifierLocBuilder::Adopt(NestedNameSpecifierLoc Other) {
+ if (BufferCapacity)
+ free(Buffer);
+
+ if (!Other) {
+ Representation = 0;
+ BufferSize = 0;
+ return;
+ }
+
+ // Rather than copying the data (which is wasteful), "adopt" the
+ // pointer (which points into the ASTContext) but set the capacity to zero to
+ // indicate that we don't own it.
+ Representation = Other.getNestedNameSpecifier();
+ Buffer = static_cast<char *>(Other.getOpaqueData());
+ BufferSize = Other.getDataLength();
+ BufferCapacity = 0;
+}
+
+NestedNameSpecifierLoc
+NestedNameSpecifierLocBuilder::getWithLocInContext(ASTContext &Context) const {
+ if (!Representation)
+ return NestedNameSpecifierLoc();
+
+ // If we adopted our data pointer from elsewhere in the AST context, there's
+ // no need to copy the memory.
+ if (BufferCapacity == 0)
+ return NestedNameSpecifierLoc(Representation, Buffer);
+
+ // FIXME: After copying the source-location information, should we free
+ // our (temporary) buffer and adopt the ASTContext-allocated memory?
+ // Doing so would optimize repeated calls to getWithLocInContext().
+ void *Mem = Context.Allocate(BufferSize, llvm::alignOf<void *>());
+ memcpy(Mem, Buffer, BufferSize);
+ return NestedNameSpecifierLoc(Representation, Mem);
+}
+