[x64] simply tweak materialization of float/double constants

src/x64/disasm-x64.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <assert.h>
 #include <stdarg.h>
 #include <stdio.h>
 
 #include "src/v8.h"
 
@@ skipping 1048 matching lines @@
         AppendToBuffer("movdqa ");
         current += PrintRightXMMOperand(current);
         AppendToBuffer(",%s", NameOfXMMRegister(regop));
       } else if (opcode == 0xD6) {
         AppendToBuffer("movq ");
         current += PrintRightXMMOperand(current);
         AppendToBuffer(",%s", NameOfXMMRegister(regop));
       } else if (opcode == 0x50) {
         AppendToBuffer("movmskpd %s,", NameOfCPURegister(regop));
         current += PrintRightXMMOperand(current);
+      } else if (opcode == 0x72) {
+        current += 1;
+        AppendToBuffer("%s,%s,%d", (regop == 6) ? "pslld" : "psrld",
+                       NameOfXMMRegister(rm), *current & 0x7f);
+        current += 1;
       } else if (opcode == 0x73) {
         current += 1;
-        DCHECK(regop == 6);
-        AppendToBuffer("psllq,%s,%d", NameOfXMMRegister(rm), *current & 0x7f);
+        AppendToBuffer("%s,%s,%d", (regop == 6) ? "psllq" : "psrlq",
+                       NameOfXMMRegister(rm), *current & 0x7f);
         current += 1;
       } else {
         const char* mnemonic = "?";
         if (opcode == 0x54) {
           mnemonic = "andpd";
         } else  if (opcode == 0x56) {
           mnemonic = "orpd";
         } else  if (opcode == 0x57) {
           mnemonic = "xorpd";
         } else if (opcode == 0x2E) {
@@ skipping 820 matching lines @@
     for (int i = 6 - static_cast<int>(pc - prev_pc); i >= 0; i--) {
       fprintf(f, "  ");
     }
     fprintf(f, "  %s\n", buffer.start());
   }
 }
 
 }  // namespace disasm
 
 #endif  // V8_TARGET_ARCH_X64