[X86][AsmParser] re-introduce 'offset' operator

Summary:
Amend MS offset operator implementation, to more closely fit with its MS counterpart:

    1. InlineAsm: evaluate non-local source entities to their (address) location
    2. Provide a mean with which one may acquire the address of an assembly label via MS syntax, rather than yielding a memory reference (i.e. "offset asm_label" and "$asm_label" should be synonymous
    3. address PR32530

Based on http://llvm.org/D37461

Fix broken test where the break appears unrelated.

- Set up appropriate memory-input rewrites for variable references.

- Intel-dialect assembly printing now correctly handles addresses by adding "offset".

- Pass offsets as immediate operands (using "r" constraint for offsets of locals).

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D71436

1 files changed, 6 insertions, 1 deletions

diff --git a/clang/lib/Sema/SemaStmtAsm.cpp b/clang/lib/Sema/SemaStmtAsm.cpp
index 5161b800191..93faf2d151f 100644
--- a/clang/lib/Sema/SemaStmtAsm.cpp
+++ b/clang/lib/Sema/SemaStmtAsm.cpp
@@ -707,8 +707,13 @@ void Sema::FillInlineAsmIdentifierInfo(Expr *Res,
   if (T->isFunctionType() || T->isDependentType())
     return Info.setLabel(Res);
   if (Res->isRValue()) {
-    if (isa<clang::EnumType>(T) && Res->EvaluateAsRValue(Eval, Context))
+    bool IsEnum = isa<clang::EnumType>(T);
+    if (DeclRefExpr *DRE = dyn_cast<clang::DeclRefExpr>(Res))
+      if (DRE->getDecl()->getKind() == Decl::EnumConstant)
+        IsEnum = true;
+    if (IsEnum && Res->EvaluateAsRValue(Eval, Context))
       return Info.setEnum(Eval.Val.getInt().getSExtValue());
+
     return Info.setLabel(Res);
   }
   unsigned Size = Context.getTypeSizeInChars(T).getQuantity();