Add support for the mips 'x' inline asm modifier.

Patch by Jack Carter.

llvm-svn: 157057

llvm/lib/Target/Mips/MipsAsmPrinter.cpp

@@ -383,6 +383,11 @@ bool MipsAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNum,
           return true;
         O << "0x" << StringRef(utohexstr(MO.getImm())).lower();
         return false;
+      case 'x': // hex const int (low 16 bits)
+        if ((MO.getType()) != MachineOperand::MO_Immediate)
+          return true;
+        O << "0x" << StringRef(utohexstr(MO.getImm() & 0xffff)).lower();
+        return false;
     }
   }
 

llvm/test/CodeGen/Mips/inlineasm-operand-code.ll

@@ -11,5 +11,11 @@ entry:
 ;CHECK:	#NO_APP
   tail call i32 asm sideeffect "addi $0,$1,${2:X}", "=r,r,I"(i32 7, i32 -3) nounwind
 
+; x with -3
+;CHECK:	#APP
+;CHECK:	addi ${{[0-9]+}},${{[0-9]+}},0xfffd
+;CHECK:	#NO_APP
+  tail call i32 asm sideeffect "addi $0,$1,${2:x}", "=r,r,I"(i32 7, i32 -3) nounwind
+
   ret i32 0
 }