[Assembler] Improve error when unable to evaluate expression.

Add a SMLoc to MCExpr. Most code does not generate or consume the SMLoc (yet).

Patch by Sanne Wouda <sanne.wouda@arm.com>!
Differential Revision: https://reviews.llvm.org/D28861

llvm-svn: 292515

1 files changed, 3 insertions, 2 deletions

diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index da54155b3b9..f8744f5542e 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -1005,7 +1005,7 @@ bool AsmParser::parsePrimaryExpr(const MCExpr *&Res, SMLoc &EndLoc) {
     }
 
     // Otherwise create a symbol ref.
-    Res = MCSymbolRefExpr::create(Sym, Variant, getContext());
+    Res = MCSymbolRefExpr::create(Sym, Variant, getContext(), FirstTokenLoc);
     return false;
   }
   case AsmToken::BigNum:
@@ -1436,6 +1436,7 @@ unsigned AsmParser::getBinOpPrecedence(AsmToken::TokenKind K,
 /// Res contains the LHS of the expression on input.
 bool AsmParser::parseBinOpRHS(unsigned Precedence, const MCExpr *&Res,
                               SMLoc &EndLoc) {
+  SMLoc StartLoc = Lexer.getLoc();
   while (true) {
     MCBinaryExpr::Opcode Kind = MCBinaryExpr::Add;
     unsigned TokPrec = getBinOpPrecedence(Lexer.getKind(), Kind);
@@ -1460,7 +1461,7 @@ bool AsmParser::parseBinOpRHS(unsigned Precedence, const MCExpr *&Res,
       return true;
 
     // Merge LHS and RHS according to operator.
-    Res = MCBinaryExpr::create(Kind, Res, RHS, getContext());
+    Res = MCBinaryExpr::create(Kind, Res, RHS, getContext(), StartLoc);
   }
 }