Build canonical types for dependently-sized array types.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@77647 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index f47e28b..51815d5 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -1371,8 +1371,7 @@
/// getDependentSizedArrayType - Returns a non-unique reference to
/// the type for a dependently-sized array of the specified element
-/// type. FIXME: We will need these to be uniqued, or at least
-/// comparable, at some point.
+/// type.
QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
Expr *NumElts,
ArrayType::ArraySizeModifier ASM,
@@ -1381,15 +1380,38 @@
assert((NumElts->isTypeDependent() || NumElts->isValueDependent()) &&
"Size must be type- or value-dependent!");
- // Since we don't unique expressions, it isn't possible to unique
- // dependently-sized array types.
+ llvm::FoldingSetNodeID ID;
+ DependentSizedArrayType::Profile(ID, *this, getCanonicalType(EltTy), ASM,
+ EltTypeQuals, NumElts);
- DependentSizedArrayType *New =
- new (*this,8) DependentSizedArrayType(EltTy, QualType(),
- NumElts, ASM, EltTypeQuals,
- Brackets);
-
- DependentSizedArrayTypes.push_back(New);
+ void *InsertPos = 0;
+ DependentSizedArrayType *Canon
+ = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
+ DependentSizedArrayType *New;
+ if (Canon) {
+ // We already have a canonical version of this array type; use it as
+ // the canonical type for a newly-built type.
+ New = new (*this,8) DependentSizedArrayType(*this, EltTy,
+ QualType(Canon, 0),
+ NumElts, ASM, EltTypeQuals,
+ Brackets);
+ } else {
+ QualType CanonEltTy = getCanonicalType(EltTy);
+ if (CanonEltTy == EltTy) {
+ New = new (*this,8) DependentSizedArrayType(*this, EltTy, QualType(),
+ NumElts, ASM, EltTypeQuals,
+ Brackets);
+ DependentSizedArrayTypes.InsertNode(New, InsertPos);
+ } else {
+ QualType Canon = getDependentSizedArrayType(CanonEltTy, NumElts,
+ ASM, EltTypeQuals,
+ SourceRange());
+ New = new (*this,8) DependentSizedArrayType(*this, EltTy, Canon,
+ NumElts, ASM, EltTypeQuals,
+ Brackets);
+ }
+ }
+
Types.push_back(New);
return QualType(New, 0);
}