Robustified address calculations on A64.

src/a64/disasm-a64.cc

Index: src/a64/disasm-a64.cc
diff --git a/src/a64/disasm-a64.cc b/src/a64/disasm-a64.cc
index 703595b42802f41c0703c6cb3ae439bb6617620a..bc3cbcd861683d5273c846d5abc34332ac61d9fb 100644
--- a/src/a64/disasm-a64.cc
+++ b/src/a64/disasm-a64.cc
@@ -1607,8 +1607,8 @@ int Disassembler::SubstitutePCRelAddressField(Instruction* instr,
     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;
 }
 
@@ -1635,8 +1635,8 @@ int Disassembler::SubstituteBranchTargetField(Instruction* instr,
     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;
 }