Print properly signed displacement in disassembler.

src/ia32/disasm-ia32.cc

 // Copyright 2011 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 389 matching lines @@
         return 5;
       } else if (rm == esp) {
         byte sib = *(modrmp + 1);
         int scale, index, base;
         get_sib(sib, &scale, &index, &base);
         if (index == esp && base == esp && scale == 0 /*times_1*/) {
           AppendToBuffer("[%s]", (this->*register_name)(rm));
           return 2;
         } else if (base == ebp) {
           int32_t disp = *reinterpret_cast<int32_t*>(modrmp + 2);
-          AppendToBuffer("[%s*%d+0x%x]",
+          AppendToBuffer("[%s*%d%s0x%x]",
                          (this->*register_name)(index),
                          1 << scale,
-                         disp);
+                         disp < 0 ? "-" : "+",
+                         disp < 0 ? -disp : disp);
           return 6;
         } else if (index != esp && base != ebp) {
           // [base+index*scale]
           AppendToBuffer("[%s+%s*%d]",
                          (this->*register_name)(base),
                          (this->*register_name)(index),
                          1 << scale);
           return 2;
         } else {
           UnimplementedInstruction();
           return 1;
         }
       } else {
         AppendToBuffer("[%s]", (this->*register_name)(rm));
         return 1;
       }
       break;
     case 1:  // fall through
     case 2:
       if (rm == esp) {
         byte sib = *(modrmp + 1);
         int scale, index, base;
         get_sib(sib, &scale, &index, &base);
-        int disp =
-            mod == 2 ? *reinterpret_cast<int32_t*>(modrmp + 2) : *(modrmp + 2);
+        int disp = mod == 2 ? *reinterpret_cast<int32_t*>(modrmp + 2)
+                            : *reinterpret_cast<int8_t*>(modrmp + 2);
         if (index == base && index == rm /*esp*/ && scale == 0 /*times_1*/) {
-          AppendToBuffer("[%s+0x%x]", (this->*register_name)(rm), disp);
+          AppendToBuffer("[%s%s0x%x]",
+                         (this->*register_name)(rm),
+                         disp < 0 ? "-" : "+",
+                         disp < 0 ? -disp : disp);
         } else {
-          AppendToBuffer("[%s+%s*%d+0x%x]",
+          AppendToBuffer("[%s+%s*%d%s0x%x]",
                          (this->*register_name)(base),
                          (this->*register_name)(index),
                          1 << scale,
-                         disp);
+                         disp < 0 ? "-" : "+",
+                         disp < 0 ? -disp : disp);
         }
         return mod == 2 ? 6 : 3;
       } else {
         // No sib.
-        int disp =
-            mod == 2 ? *reinterpret_cast<int32_t*>(modrmp + 1) :
-                       *reinterpret_cast<int8_t*>(modrmp + 1);
+        int disp = mod == 2 ? *reinterpret_cast<int32_t*>(modrmp + 1)
+                            : *reinterpret_cast<int8_t*>(modrmp + 1);
         AppendToBuffer("[%s%s0x%x]",
                        (this->*register_name)(rm),
                        disp < 0 ? "-" : "+",
                        disp < 0 ? -disp : disp);
         return mod == 2 ? 5 : 2;
       }
       break;
     case 3:
       AppendToBuffer("%s", (this->*register_name)(rm));
       return 1;
@@ skipping 1308 matching lines @@
       fprintf(f, "  ");
     }
     fprintf(f, "  %s\n", buffer.start());
   }
 }
 
 
 }  // namespace disasm
 
 #endif  // V8_TARGET_ARCH_IA32