Split out types that are non-canonical unless dependent as their own

category.  Use this in a few places to eliminate unnecessary TST cases and
do some future-proofing.  Provide terrible manglings for typeof.  Mangle
decltype with some hope of accuracy.

Our manglings for some of the cases covered in the testcase are different
from gcc's, which I've raised as an issue with the ABI list.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@97523 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 39 insertions, 1 deletions

diff --git a/lib/CodeGen/Mangle.cpp b/lib/CodeGen/Mangle.cpp
index d9a7991f78..64743c7696 100644
--- a/lib/CodeGen/Mangle.cpp
+++ b/lib/CodeGen/Mangle.cpp
@@ -455,7 +455,9 @@ void CXXNameMangler::mangleUnresolvedScope(NestedNameSpecifier *Qualifier) {
     mangleType(QualType(Qualifier->getAsType(), 0));
     break;
   case NestedNameSpecifier::Identifier:
-    mangleUnresolvedScope(Qualifier->getPrefix());
+    // Member expressions can have these without prefixes.
+    if (Qualifier->getPrefix())
+      mangleUnresolvedScope(Qualifier->getPrefix());
     mangleSourceName(Qualifier->getAsIdentifier());
     break;
   }
@@ -1123,6 +1125,42 @@ void CXXNameMangler::mangleType(const TypenameType *T) {
   Out << 'E';
 }
 
+void CXXNameMangler::mangleType(const TypeOfType *T) {
+  // FIXME: this is pretty unsatisfactory, but there isn't an obvious
+  // "extension with parameters" mangling.
+  Out << "u6typeof";
+}
+
+void CXXNameMangler::mangleType(const TypeOfExprType *T) {
+  // FIXME: this is pretty unsatisfactory, but there isn't an obvious
+  // "extension with parameters" mangling.
+  Out << "u6typeof";
+}
+
+void CXXNameMangler::mangleType(const DecltypeType *T) {
+  Expr *E = T->getUnderlyingExpr();
+  
+  // type ::= Dt <expression> E  # decltype of an id-expression
+  //                             #   or class member access
+  //      ::= DT <expression> E  # decltype of an expression
+
+  // This purports to be an exhaustive list of id-expressions and
+  // class member accesses.  Note that we do not ignore parentheses;
+  // parentheses change the semantics of decltype for these
+  // expressions (and cause the mangler to use the other form).
+  if (isa<DeclRefExpr>(E) ||
+      isa<MemberExpr>(E) ||
+      isa<UnresolvedLookupExpr>(E) ||
+      isa<DependentScopeDeclRefExpr>(E) ||
+      isa<CXXDependentScopeMemberExpr>(E) ||
+      isa<UnresolvedMemberExpr>(E))
+    Out << "Dt";
+  else
+    Out << "DT";
+  mangleExpression(E);
+  Out << 'E';
+}
+
 void CXXNameMangler::mangleIntegerLiteral(QualType T, 
                                           const llvm::APSInt &Value) {
   //  <expr-primary> ::= L <type> <value number> E # integer literal