[AST] Introduce a new DecayedType sugar node
The goal of this sugar node is to be able to look at an arbitrary
FunctionType and tell if any of the parameters were decayed from an
array or function type. Ultimately this is necessary to implement
Microsoft's C++ name mangling scheme, which mangles decayed arrays
differently from normal pointers.
Reviewers: rsmith
Differential Revision: http://llvm-reviews.chandlerc.com/D1014
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@184763 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index 70c933e..9105940 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -1615,6 +1615,8 @@
}
case Type::ObjCObject:
return getTypeInfo(cast<ObjCObjectType>(T)->getBaseType().getTypePtr());
+ case Type::Decayed:
+ return getTypeInfo(cast<DecayedType>(T)->getDecayedType().getTypePtr());
case Type::ObjCInterface: {
const ObjCInterfaceType *ObjCI = cast<ObjCInterfaceType>(T);
const ASTRecordLayout &Layout = getASTObjCInterfaceLayout(ObjCI->getDecl());
@@ -2167,6 +2169,45 @@
return QualType(New, 0);
}
+QualType ASTContext::getDecayedType(QualType T) const {
+ assert((T->isArrayType() || T->isFunctionType()) && "T does not decay");
+
+ llvm::FoldingSetNodeID ID;
+ DecayedType::Profile(ID, T);
+ void *InsertPos = 0;
+ if (DecayedType *DT = DecayedTypes.FindNodeOrInsertPos(ID, InsertPos))
+ return QualType(DT, 0);
+
+ QualType Decayed;
+
+ // C99 6.7.5.3p7:
+ // A declaration of a parameter as "array of type" shall be
+ // adjusted to "qualified pointer to type", where the type
+ // qualifiers (if any) are those specified within the [ and ] of
+ // the array type derivation.
+ if (T->isArrayType())
+ Decayed = getArrayDecayedType(T);
+
+ // C99 6.7.5.3p8:
+ // A declaration of a parameter as "function returning type"
+ // shall be adjusted to "pointer to function returning type", as
+ // in 6.3.2.1.
+ if (T->isFunctionType())
+ Decayed = getPointerType(T);
+
+ QualType Canonical = getCanonicalType(Decayed);
+
+ // Get the new insert position for the node we care about.
+ DecayedType *NewIP = DecayedTypes.FindNodeOrInsertPos(ID, InsertPos);
+ assert(NewIP == 0 && "Shouldn't be in the map!"); (void)NewIP;
+
+ DecayedType *New =
+ new (*this, TypeAlignment) DecayedType(T, Decayed, Canonical);
+ Types.push_back(New);
+ DecayedTypes.InsertNode(New, InsertPos);
+ return QualType(New, 0);
+}
+
/// getBlockPointerType - Return the uniqued reference to the type for
/// a pointer to the specified block.
QualType ASTContext::getBlockPointerType(QualType T) const {
@@ -4154,22 +4195,9 @@
}
QualType ASTContext::getAdjustedParameterType(QualType T) const {
- // C99 6.7.5.3p7:
- // A declaration of a parameter as "array of type" shall be
- // adjusted to "qualified pointer to type", where the type
- // qualifiers (if any) are those specified within the [ and ] of
- // the array type derivation.
- if (T->isArrayType())
- return getArrayDecayedType(T);
-
- // C99 6.7.5.3p8:
- // A declaration of a parameter as "function returning type"
- // shall be adjusted to "pointer to function returning type", as
- // in 6.3.2.1.
- if (T->isFunctionType())
- return getPointerType(T);
-
- return T;
+ if (T->isArrayType() || T->isFunctionType())
+ return getDecayedType(T);
+ return T;
}
QualType ASTContext::getSignatureParameterType(QualType T) const {