Fix the assembler to print a better relocatable expression error

diagnostic that includes location information.

Currently if one has this assembly:

	.quad (0x1234 + (4 * SOME_VALUE))

where SOME_VALUE is undefined ones gets the less than
useful error message with no location information:

% clang -c x.s
clang -cc1as: fatal error: error in backend: expected relocatable expression

With this fix one now gets a more useful error message
with location information:

% clang -c x.s 
x.s:5:8: error: expected relocatable expression
 .quad (0x1234 + (4 * SOME_VALUE))
       ^

To do this I plumbed the SMLoc through the MCObjectStreamer
EmitValue() and EmitValueImpl() interfaces so it could be used
when creating the MCFixup.

rdar://12391022

llvm-svn: 206906

1 files changed, 3 insertions, 2 deletions

diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index f85f7d3210c..50b6576766c 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -147,8 +147,9 @@ void MCStreamer::EmitAbsValue(const MCExpr *Value, unsigned Size) {
 }
 
 
-void MCStreamer::EmitValue(const MCExpr *Value, unsigned Size) {
-  EmitValueImpl(Value, Size);
+void MCStreamer::EmitValue(const MCExpr *Value, unsigned Size,
+                           const SMLoc &Loc) {
+  EmitValueImpl(Value, Size, Loc);
 }
 
 void MCStreamer::EmitSymbolValue(const MCSymbol *Sym, unsigned Size) {