diff --git a/lib/AsmParser/Lexer.l b/lib/AsmParser/Lexer.l
index b67f6ff1024..2218aa5164b 100644
--- a/lib/AsmParser/Lexer.l
+++ b/lib/AsmParser/Lexer.l
@@ -161,6 +161,7 @@ QuoteLabel \"[^\"]+\":
 /* Quoted names can contain any character except " and \ */
 StringConstant \"[^\"]*\"
 AtStringConstant @\"[^\"]*\"
+PctStringConstant %\"[^\"]*\"
   
 /* LocalVarID/GlobalVarID: match an unnamed local variable slot ID. */
 LocalVarID     %[0-9]+
@@ -366,6 +367,11 @@ shufflevector   { RET_TOK(OtherOpVal, ShuffleVector, SHUFFLEVECTOR); }
                      return ATSTRINGCONSTANT;
                    }
 
+{PctStringConstant} {
+                     yytext[strlen(yytext)-1] = 0;           // nuke end quote
+                     llvmAsmlval.StrVal = strdup(yytext+2);  // Nuke @, quote
+                     return PCTSTRINGCONSTANT;
+                   }
 {PInteger}      { int len = strlen(yytext); 
                   uint32_t numBits = ((len * 64) / 19) + 1;
                   APInt Tmp(numBits, yytext, len, 10);
diff --git a/lib/AsmParser/llvmAsmParser.y b/lib/AsmParser/llvmAsmParser.y
index d8e151c48d5..30a1fe6ffb1 100644
--- a/lib/AsmParser/llvmAsmParser.y
+++ b/lib/AsmParser/llvmAsmParser.y
@@ -1051,7 +1051,8 @@ Module *llvm::RunVMAsmParser(const char * AsmString, Module * M) {
 %token <PrimType> FLOAT DOUBLE LABEL
 %token TYPE
 
-%token<StrVal> LOCALVAR GLOBALVAR LABELSTR STRINGCONSTANT ATSTRINGCONSTANT
+%token<StrVal> LOCALVAR GLOBALVAR LABELSTR 
+%token<StrVal> STRINGCONSTANT ATSTRINGCONSTANT PCTSTRINGCONSTANT
 %type <StrVal> LocalName OptLocalName OptLocalAssign
 %type <StrVal> GlobalName OptGlobalAssign GlobalAssign
 %type <UIntVal> OptAlign OptCAlign
@@ -1138,7 +1139,7 @@ FPredicates
 IntType :  INTTYPE;
 FPType   : FLOAT | DOUBLE;
 
-LocalName : LOCALVAR | STRINGCONSTANT;
+LocalName : LOCALVAR | STRINGCONSTANT | PCTSTRINGCONSTANT
 OptLocalName : LocalName | /*empty*/ { $$ = 0; };
 
 /// OptLocalAssign - Value producing statements have an optional assignment