Revert of [turbofan] Implemented the TruncateFloat32ToInt64 TurboFan operator.

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>
 
 #if V8_TARGET_ARCH_X64
 
@@ skipping 971 matching lines @@
         if (mod == 3) {
           AppendToBuffer(",%s", NameOfXMMRegister(vvvv));
         }
         AppendToBuffer(",%s", NameOfXMMRegister(regop));
         break;
       case 0x2a:
         AppendToBuffer("%s %s,%s,", vex_w() ? "vcvtqsi2ss" : "vcvtlsi2ss",
                        NameOfXMMRegister(regop), NameOfXMMRegister(vvvv));
         current += PrintRightOperand(current);
         break;
-      case 0x2c:
-        AppendToBuffer("vcvttss2si%s %s,", vex_w() ? "q" : "",
-                       NameOfCPURegister(regop));
-        current += PrintRightXMMOperand(current);
-        break;
       case 0x58:
         AppendToBuffer("vaddss %s,%s,", NameOfXMMRegister(regop),
                        NameOfXMMRegister(vvvv));
         current += PrintRightXMMOperand(current);
         break;
       case 0x59:
         AppendToBuffer("vmulss %s,%s,", NameOfXMMRegister(regop),
                        NameOfXMMRegister(vvvv));
         current += PrintRightXMMOperand(current);
         break;
@@ skipping 1483 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