Fix AsmParser binary precedence for shift operators.

rdar://9976729

llvm-svn: 138208

lib/MC/MCParser/AsmParser.cpp

@@ -740,9 +740,12 @@ AsmParser::ApplyModifierToExpr(const MCExpr *E,
 
 /// ParseExpression - Parse an expression and return it.
 ///
-///  expr ::= expr +,- expr          -> lowest.
-///  expr ::= expr |,^,&,! expr      -> middle.
-///  expr ::= expr *,/,%,<<,>> expr  -> highest.
+///  expr ::= expr &&,|| expr               -> lowest.
+///  expr ::= expr |,^,&,! expr
+///  expr ::= expr ==,!=,<>,<,<=,>,>= expr
+///  expr ::= expr <<,>> expr
+///  expr ::= expr +,- expr
+///  expr ::= expr *,/,% expr               -> highest.
 ///  expr ::= primaryexpr
 ///
 bool AsmParser::ParseExpression(const MCExpr *&Res, SMLoc &EndLoc) {
@@ -809,7 +812,7 @@ static unsigned getBinOpPrecedence(AsmToken::TokenKind K,
   default:
     return 0;    // not a binop.
 
-    // Lowest Precedence: &&, ||, @
+    // Lowest Precedence: &&, ||
   case AsmToken::AmpAmp:
     Kind = MCBinaryExpr::LAnd;
     return 1;
@@ -852,30 +855,32 @@ static unsigned getBinOpPrecedence(AsmToken::TokenKind K,
     Kind = MCBinaryExpr::GTE;
     return 3;
 
+    // Intermediate Precedence: <<, >>
+  case AsmToken::LessLess:
+    Kind = MCBinaryExpr::Shl;
+    return 4;
+  case AsmToken::GreaterGreater:
+    Kind = MCBinaryExpr::Shr;
+    return 4;
+
     // High Intermediate Precedence: +, -
   case AsmToken::Plus:
     Kind = MCBinaryExpr::Add;
-    return 4;
+    return 5;
   case AsmToken::Minus:
     Kind = MCBinaryExpr::Sub;
-    return 4;
+    return 5;
 
-    // Highest Precedence: *, /, %, <<, >>
+    // Highest Precedence: *, /, %
   case AsmToken::Star:
     Kind = MCBinaryExpr::Mul;
-    return 5;
+    return 6;
   case AsmToken::Slash:
     Kind = MCBinaryExpr::Div;
-    return 5;
+    return 6;
   case AsmToken::Percent:
     Kind = MCBinaryExpr::Mod;
-    return 5;
-  case AsmToken::LessLess:
-    Kind = MCBinaryExpr::Shl;
-    return 5;
-  case AsmToken::GreaterGreater:
-    Kind = MCBinaryExpr::Shr;
-    return 5;
+    return 6;
   }
 }
 

test/MC/AsmParser/exprs.s

@@ -44,6 +44,7 @@ k:
         check_expr 0 || 1, 1
         check_expr 0 || 0, 0
         check_expr 1 + 2 < 3 + 4, 1
+        check_expr 1 << 8 - 1, 128
 
         .set c, 10
         check_expr c + 1, 11