S390: Optimize For Mul in TurboFan codegen

src/s390/assembler-s390.cc

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // All Rights Reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions
 // are met:
 //
 // - Redistributions of source code must retain the above copyright notice,
 // this list of conditions and the following disclaimer.
 //
@@ skipping 2080 matching lines @@
 // Subtract Logical Register-Register-Register (64)
 void Assembler::slgrk(Register r1, Register r2, Register r3) {
   rrf1_form(SLGRK, r1, r2, r3);
 }
 
 // ----------------------------
 // 32-bit Multiply Instructions
 // ----------------------------
 // Multiply Register-Storage (64<32)
 void Assembler::m(Register r1, const MemOperand& opnd) {
+  DCHECK(r1.code() % 2 == 0);
   rx_form(M, r1, opnd.rx(), opnd.rb(), opnd.offset());
 }
 
+void Assembler::mfy(Register r1, const MemOperand& opnd) {
+  DCHECK(r1.code() % 2 == 0);
+  rxy_form(MFY, r1, opnd.rx(), opnd.rb(), opnd.offset());
+}
+
 // Multiply Register (64<32)
 void Assembler::mr_z(Register r1, Register r2) {
   DCHECK(r1.code() % 2 == 0);
   rr_form(MR, r1, r2);
 }
 
 // Multiply Logical Register-Storage (64<32)
 void Assembler::ml(Register r1, const MemOperand& opnd) {
   rxy_form(ML, r1, opnd.rx(), opnd.rb(), opnd.offset());
 }
@@ skipping 1008 matching lines @@
                             SKIP_ICACHE_FLUSH);
     }
 
     reloc_info_writer.Write(&rinfo);
   }
 }
 
 }  // namespace internal
 }  // namespace v8
 #endif  // V8_TARGET_ARCH_S390