Improve handling of __FUNCTION__ and other predefined expression for Objective-C Blocks

Instead of always displaying the mangled name, try to do better
and get something closer to regular functions.

Recommit r287039 (that was reverted in r287039) with a tweak to
be more generic, and test fixes!

Differential Revision: https://reviews.llvm.org/D26522

llvm-svn: 287085

1 files changed, 13 insertions, 3 deletions

diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index 08e1cad5305..6db668204f5 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -2319,9 +2319,19 @@ LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
   StringRef NameItems[] = {
       PredefinedExpr::getIdentTypeName(E->getIdentType()), FnName};
   std::string GVName = llvm::join(NameItems, NameItems + 2, ".");
-  if (CurCodeDecl && isa<BlockDecl>(CurCodeDecl)) {
-    auto C = CGM.GetAddrOfConstantCString(FnName, GVName.c_str());
-    return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
+  if (auto *BD = dyn_cast<BlockDecl>(CurCodeDecl)) {
+    std::string Name = SL->getString();
+    if (!Name.empty()) {
+      unsigned Discriminator =
+          CGM.getCXXABI().getMangleContext().getBlockId(BD, true);
+      if (Discriminator)
+        Name += "_" + Twine(Discriminator + 1).str();
+      auto C = CGM.GetAddrOfConstantCString(Name, GVName.c_str());
+      return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
+    } else {
+      auto C = CGM.GetAddrOfConstantCString(FnName, GVName.c_str());
+      return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
+    }
   }
   auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName);
   return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);