VariableArrayTypes (VLAs) without a size expression are now uniqued
and inserted into a FoldingSet owned by ASTContext.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@43482 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/AST/ASTContext.cpp b/AST/ASTContext.cpp
index 93d4232..72511bd 100644
--- a/AST/ASTContext.cpp
+++ b/AST/ASTContext.cpp
@@ -451,11 +451,49 @@
QualType ASTContext::getVariableArrayType(QualType EltTy, Expr *NumElts,
ArrayType::ArraySizeModifier ASM,
unsigned EltTypeQuals) {
- // Since we don't unique expressions, it isn't possible to unique VLA's.
- ArrayType *New = new VariableArrayType(EltTy, QualType(), NumElts,
- ASM, EltTypeQuals);
- Types.push_back(New);
- return QualType(New, 0);
+ if (NumElts) {
+ // Since we don't unique expressions, it isn't possible to unique VLA's
+ // that have an expression provided for their size.
+
+ ArrayType *New = new VariableArrayType(EltTy, QualType(), NumElts,
+ ASM, EltTypeQuals);
+
+ // FIXME: Also add non-uniqued VLAs into a list of their own.
+ Types.push_back(New);
+ return QualType(New, 0);
+ }
+ else {
+ // No size is provided for the VLA. These we can unique.
+ llvm::FoldingSetNodeID ID;
+ VariableArrayType::Profile(ID, EltTy);
+
+ void *InsertPos = 0;
+ if (VariableArrayType *ATP =
+ IncompleteVariableArrayTypes.FindNodeOrInsertPos(ID, InsertPos))
+ return QualType(ATP, 0);
+
+ // If the element type isn't canonical, this won't be a canonical type
+ // either, so fill in the canonical type field.
+ QualType Canonical;
+
+ if (!EltTy->isCanonical()) {
+ Canonical = getVariableArrayType(EltTy.getCanonicalType(), NumElts,
+ ASM, EltTypeQuals);
+
+ // Get the new insert position for the node we care about.
+ VariableArrayType *NewIP =
+ IncompleteVariableArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
+
+ assert(NewIP == 0 && "Shouldn't be in the map!");
+ }
+
+ VariableArrayType *New = new VariableArrayType(EltTy, QualType(), NumElts,
+ ASM, EltTypeQuals);
+
+ IncompleteVariableArrayTypes.InsertNode(New, InsertPos);
+ Types.push_back(New);
+ return QualType(New, 0);
+ }
}
/// getVectorType - Return the unique reference to a vector type of
diff --git a/include/clang/AST/ASTContext.h b/include/clang/AST/ASTContext.h
index 3169726..48e7e13 100644
--- a/include/clang/AST/ASTContext.h
+++ b/include/clang/AST/ASTContext.h
@@ -29,12 +29,13 @@
/// ASTContext - This class holds long-lived AST nodes (such as types and
/// decls) that can be referred to throughout the semantic analysis of a file.
-class ASTContext {
+class ASTContext {
std::vector<Type*> Types;
llvm::FoldingSet<ComplexType> ComplexTypes;
llvm::FoldingSet<PointerType> PointerTypes;
llvm::FoldingSet<ReferenceType> ReferenceTypes;
llvm::FoldingSet<ConstantArrayType> ArrayTypes;
+ llvm::FoldingSet<VariableArrayType> IncompleteVariableArrayTypes;
llvm::FoldingSet<VectorType> VectorTypes;
llvm::FoldingSet<FunctionTypeNoProto> FunctionTypeNoProtos;
llvm::FoldingSet<FunctionTypeProto> FunctionTypeProtos;
diff --git a/include/clang/AST/Type.h b/include/clang/AST/Type.h
index 59178b8..052f580 100644
--- a/include/clang/AST/Type.h
+++ b/include/clang/AST/Type.h
@@ -573,7 +573,7 @@
};
// FIXME: VariableArrayType's aren't uniqued (since expressions aren't).
-class VariableArrayType : public ArrayType {
+class VariableArrayType : public ArrayType, public llvm::FoldingSetNode {
/// SizeExpr - An assignment expression. VLA's are only permitted within
/// a function block.
Expr *SizeExpr;
@@ -593,6 +593,18 @@
static bool classof(const VariableArrayType *) { return true; }
friend class StmtIteratorBase;
+
+ void Profile(llvm::FoldingSetNodeID &ID) {
+ assert (SizeExpr == NULL
+ && "Can only unique VariableArrayTypes with no specified size.");
+
+ Profile(ID, getElementType());
+ }
+
+ static void Profile(llvm::FoldingSetNodeID &ID, QualType ET) {
+ ID.AddPointer(ET.getAsOpaquePtr());
+ }
+
// FIXME: Who owns VariableArrayType's? What are the semantics
// for serialization.
};