Fix warnings on Win64.

src/x64/disasm-x64.cc

 // Copyright 2009 the V8 project authors. 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.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1051 matching lines @@
   } else if (opcode == 0x2C && group_1_prefix_ == 0xF3) {
     // Instruction with prefix 0xF3.
 
     // CVTTSS2SI: Convert scalar single-precision FP to dword integer.
     // Assert that mod is not 3, so source is memory, not an XMM register.
     ASSERT_NE(0xC0, *current & 0xC0);
     current += PrintOperands("cvttss2si", REG_OPER_OP_ORDER, current);
   } else {
     UnimplementedInstruction();
   }
-  return current - data;
+  return static_cast<int>(current - data);
 }
 
 
 // Mnemonics for two-byte opcode instructions starting with 0x0F.
 // The argument is the second byte of the two-byte opcode.
 // Returns NULL if the instruction is not handled here.
 const char* DisassemblerX64::TwoByteMnemonic(byte opcode) {
   switch (opcode) {
     case 0x1F:
       return "nop";
@@ skipping 384 matching lines @@
       default:
         UnimplementedInstruction();
         data += 1;
     }
   }  // !processed
 
   if (tmp_buffer_pos_ < sizeof tmp_buffer_) {
     tmp_buffer_[tmp_buffer_pos_] = '\0';
   }
 
-  int instr_len = data - instr;
+  int instr_len = static_cast<int>(data - instr);
   ASSERT(instr_len > 0);  // Ensure progress.
 
   int outp = 0;
   // Instruction bytes.
   for (byte* bp = instr; bp < data; bp++) {
     outp += v8::internal::OS::SNPrintF(out_buffer + outp, "%02x", *bp);
   }
   for (int i = 6 - instr_len; i >= 0; i--) {
     outp += v8::internal::OS::SNPrintF(out_buffer + outp, "  ");
   }
@@ skipping 91 matching lines @@
     v8::internal::EmbeddedVector<char, 128> buffer;
     buffer[0] = '\0';
     byte* prev_pc = pc;
     pc += d.InstructionDecode(buffer, pc);
     fprintf(f, "%p", prev_pc);
     fprintf(f, "    ");
 
     for (byte* bp = prev_pc; bp < pc; bp++) {
       fprintf(f, "%02x", *bp);
     }
-    for (int i = 6 - (pc - prev_pc); i >= 0; i--) {
+    for (int i = 6 - static_cast<int>(pc - prev_pc); i >= 0; i--) {
       fprintf(f, "  ");
     }
     fprintf(f, "  %s\n", buffer.start());
   }
 }
 
 }  // namespace disasm