Change the informal convention of DBG_VALUE so that we can express a
register-indirect address with an offset of 0.
It used to be that a DBG_VALUE is a register-indirect value if the offset
(operand 1) is nonzero. The new convention is that a DBG_VALUE is
register-indirect if the first operand is a register and the second
operand is an immediate. For plain registers use the combination reg, reg.

rdar://problem/13658587

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180816 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 4a71ad3..284b616 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -597,7 +597,9 @@
     OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg());
   }
 
-  OS << '+' << MI->getOperand(1).getImm();
+  // It's only an offset if it's an immediate.
+  if (MI->getOperand(1).isImm())
+    OS << '+' << MI->getOperand(1).getImm();
   // NOTE: Want this comment at start of line, don't emit with AddComment.
   AP.OutStreamer.EmitRawText(OS.str());
   return true;