Make sure we always have room for patching the reloc info during lazy deoptim...

src/ia32/deoptimizer-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 62 matching lines @@
   RelocInfoWriter reloc_info_writer(reloc_end_address, code_start_address);
 
   // For each return after a safepoint insert a call to the corresponding
   // deoptimization entry.  Since the call is a relative encoding, write new
   // reloc info.  We do not need any of the existing reloc info because the
   // existing code will not be used again (we zap it in debug builds).
   SafepointTable table(code);
   Address prev_address = code_start_address;
   for (unsigned i = 0; i < table.length(); ++i) {
     Address curr_address = code_start_address + table.GetPcOffset(i);
+    ASSERT_GE(curr_address - prev_address, patch_size());
     ZapCodeRange(prev_address, curr_address);
 
     SafepointEntry safepoint_entry = table.GetEntry(i);
     int deoptimization_index = safepoint_entry.deoptimization_index();
     if (deoptimization_index != Safepoint::kNoDeoptimizationIndex) {
       // The gap code is needed to get to the state expected at the bailout.
       curr_address += safepoint_entry.gap_code_size();
 
       CodePatcher patcher(curr_address, patch_size());
       Address deopt_entry = GetDeoptimizationEntry(deoptimization_index, LAZY);
       patcher.masm()->call(deopt_entry, RelocInfo::NONE);
 
       // We use RUNTIME_ENTRY for deoptimization bailouts.
       RelocInfo rinfo(curr_address + 1,  // 1 after the call opcode.
                       RelocInfo::RUNTIME_ENTRY,
                       reinterpret_cast<intptr_t>(deopt_entry));
       reloc_info_writer.Write(&rinfo);
-
+      ASSERT_GE(reloc_info_writer.pos(),
+                reloc_info->address() + ByteArray::kHeaderSize);
       curr_address += patch_size();
     }
     prev_address = curr_address;
   }
   ZapCodeRange(prev_address,
                code_start_address + code->safepoint_table_offset());
 
   // Move the relocation info to the beginning of the byte array.
   int new_reloc_size = reloc_end_address - reloc_info_writer.pos();
   memmove(code->relocation_start(), reloc_info_writer.pos(), new_reloc_size);
@@ skipping 540 matching lines @@
   }
   __ bind(&done);
 }
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32