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/MCObjectStreamer.cpp b/llvm/lib/MC/MCObjectStreamer.cpp
index 50f67c1..ea3f425 100644
--- a/llvm/lib/MC/MCObjectStreamer.cpp
+++ b/llvm/lib/MC/MCObjectStreamer.cpp
@@ -97,7 +97,8 @@ const MCExpr *MCObjectStreamer::AddValueSymbols(const MCExpr *Value) {
   return Value;
 }
 
-void MCObjectStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size) {
+void MCObjectStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size,
+                                     const SMLoc &Loc) {
   MCDataFragment *DF = getOrCreateDataFragment();
 
   MCLineEntry::Make(this, getCurrentSection().first);
@@ -110,7 +111,7 @@ void MCObjectStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size) {
   }
   DF->getFixups().push_back(
       MCFixup::Create(DF->getContents().size(), Value,
-                      MCFixup::getKindForSize(Size, false)));
+                      MCFixup::getKindForSize(Size, false), Loc));
   DF->getContents().resize(DF->getContents().size() + Size, 0);
 }