Enable the %s modifier in inline asm template string

This patch corresponds to review:
http://reviews.llvm.org/D16847

There are some files in glibc that use the output operand modifier even though
it was deprecated in GCC. This patch just adds support for it to prevent issues
with such files.

llvm-svn: 259798

lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp

@@ -555,6 +555,11 @@ bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
         return true;
       O << -MO.getImm();
       return false;
+    case 's':  // The GCC deprecated s modifier
+      if (MO.getType() != MachineOperand::MO_Immediate)
+        return true;
+      O << ((32 - MO.getImm()) & 31);
+      return false;
     }
   }
   return true;