Robustified address calculations on A64.

src/a64/disasm-a64.cc

 // Copyright 2013 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 1589 matching lines @@
   int offset = instr->ImmPCRel();
 
   // Only ADR (AddrPCRelByte) is supported.
   ASSERT(strcmp(format, "AddrPCRelByte") == 0);
 
   char sign = '+';
   if (offset < 0) {
     offset = -offset;
     sign = '-';
   }
-  STATIC_ASSERT(sizeof(*instr) == 1);
-  AppendToOutput("#%c0x%x (addr %p)", sign, offset, instr + offset);
+  AppendToOutput("#%c0x%x (addr %p)", sign, offset,
+                 instr->InstructionAtOffset(offset, Instruction::NO_CHECK));
   return 13;
 }
 
 
 int Disassembler::SubstituteBranchTargetField(Instruction* instr,
                                               const char* format) {
   ASSERT(strncmp(format, "BImm", 4) == 0);
 
   int64_t offset = 0;
   switch (format[5]) {
     // BImmUncn - unconditional branch immediate.
     case 'n': offset = instr->ImmUncondBranch(); break;
     // BImmCond - conditional branch immediate.
     case 'o': offset = instr->ImmCondBranch(); break;
     // BImmCmpa - compare and branch immediate.
     case 'm': offset = instr->ImmCmpBranch(); break;
     // BImmTest - test and branch immediate.
     case 'e': offset = instr->ImmTestBranch(); break;
     default: UNREACHABLE();
   }
   offset <<= kInstructionSizeLog2;
   char sign = '+';
   if (offset < 0) {
     offset = -offset;
     sign = '-';
   }
-  STATIC_ASSERT(sizeof(*instr) == 1);
-  AppendToOutput("#%c0x%" PRIx64 " (addr %p)", sign, offset, instr + offset);
+  AppendToOutput("#%c0x%" PRIx64 " (addr %p)", sign, offset,
+                 instr->InstructionAtOffset(offset), Instruction::NO_CHECK);
   return 8;
 }
 
 
 int Disassembler::SubstituteExtendField(Instruction* instr,
                                         const char* format) {
   ASSERT(strncmp(format, "Ext", 3) == 0);
   ASSERT(instr->ExtendMode() <= 7);
   USE(format);
 
@@ skipping 197 matching lines @@
   decoder.AppendVisitor(&disasm);
 
   for (byte* pc = start; pc < end; pc += v8::internal::kInstructionSize) {
     decoder.Decode(reinterpret_cast<v8::internal::Instruction*>(pc));
   }
 }
 
 }  // namespace disasm
 
 #endif  // V8_TARGET_ARCH_A64