[ARM,AArch64] Store source location for values in assembly files

[olista01]

Summary

The MCValue class can store a SMLoc to allow better error messages to be emitted if an error is detected after parsing. The ARM and AArch64 assembly parsers were not setting this, so error messages did not have source information.

[rengolin]

LGTM, thanks!

llvm/trunk/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp

 bool AArch64AsmParser::parseDirectiveWord(unsigned Size, SMLoc L) {
   MCAsmParser &Parser = getParser();
   if (getLexer().isNot(AsmToken::EndOfStatement)) {
     for (;;) {
       const MCExpr *Value;
       if (getParser().parseExpression(Value))
         return true;
 
-      getParser().getStreamer().EmitValue(Value, Size);
+      getParser().getStreamer().EmitValue(Value, Size, L);
 
       if (getLexer().is(AsmToken::EndOfStatement))
         break;
 
       // FIXME: Improve diagnostic.
       if (getLexer().isNot(AsmToken::Comma))
         return Error(L, "unexpected token in directive");
       Parser.Lex();

llvm/trunk/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp

void EmitBytes(StringRef Data) override {
     MCELFStreamer::EmitBytes(Data);
   }
 
   /// This is one of the functions used to emit data into an ELF section, so the
   /// AArch64 streamer overrides it to add the appropriate mapping symbol ($d)
   /// if necessary.
   void EmitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) override {
     EmitDataMappingSymbol();
-    MCELFStreamer::EmitValueImpl(Value, Size);
+    MCELFStreamer::EmitValueImpl(Value, Size, Loc);
   }
 
 private:
   enum ElfMappingSymbol {
     EMS_None,
     EMS_A64,
     EMS_Data
   };

llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp

bool ARMAsmParser::parseLiteralValues(unsigned Size, SMLoc L) {
   if (getLexer().isNot(AsmToken::EndOfStatement)) {
     for (;;) {
       const MCExpr *Value;
       if (getParser().parseExpression(Value)) {
         Parser.eatToEndOfStatement();
         return false;
       }
 
-      getParser().getStreamer().EmitValue(Value, Size);
+      getParser().getStreamer().EmitValue(Value, Size, L);
 
       if (getLexer().is(AsmToken::EndOfStatement))
         break;
 
       // FIXME: Improve diagnostic.
       if (getLexer().isNot(AsmToken::Comma)) {
         Error(L, "unexpected token in directive");
         return false;

llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp

public:
   /// ARM streamer overrides it to add the appropriate mapping symbol ($d) if
   /// necessary.
   void EmitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) override {
     if (const MCSymbolRefExpr *SRE = dyn_cast_or_null<MCSymbolRefExpr>(Value))
       if (SRE->getKind() == MCSymbolRefExpr::VK_ARM_SBREL && !(Size == 4))
         getContext().reportFatalError(Loc, "relocated expression must be 32-bit");
 
     EmitDataMappingSymbol();
-    MCELFStreamer::EmitValueImpl(Value, Size);
+    MCELFStreamer::EmitValueImpl(Value, Size, Loc);
   }
 
   void EmitAssemblerFlag(MCAssemblerFlag Flag) override {
     MCELFStreamer::EmitAssemblerFlag(Flag);
 
     switch (Flag) {
     case MCAF_SyntaxUnified:
       return; // no-op here.

llvm/trunk/test/MC/AArch64/error-location.s

+// RUN: not llvm-mc -triple aarch64--none-eabi -filetype obj < %s -o /dev/null 2>&1 | FileCheck %s
+
+  .text
+// CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: symbol 'undef' can not be undefined in a subtraction expression
+  .word (0-undef)

llvm/trunk/test/MC/ARM/error-location.s

+@ RUN: not llvm-mc -triple armv7a--none-eabi -filetype obj < %s -o /dev/null 2>&1 | FileCheck %s
+
+  .text
+@ CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: symbol 'undef' can not be undefined in a subtraction expression
+  .word (0-undef)