Partial fix for V8 issue 1079.

src/arm/deoptimizer-arm.cc

-// Copyright 2010 the V8 project authors. All rights reserved.
+// 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
 //       with the distribution.
@@ skipping 18 matching lines @@
 #include "codegen.h"
 #include "deoptimizer.h"
 #include "full-codegen.h"
 #include "safepoint-table.h"
 
 namespace v8 {
 namespace internal {
 
 int Deoptimizer::table_entry_size_ = 16;
 
+
+int Deoptimizer::patch_size() {
+  const int kCallInstructionSizeInWords = 3;
+  return kCallInstructionSizeInWords * Assembler::kInstrSize;
+}
+
+
+
 void Deoptimizer::DeoptimizeFunction(JSFunction* function) {
   AssertNoAllocation no_allocation;
 
   if (!function->IsOptimized()) return;
 
   // Get the optimized code.
   Code* code = function->code();
 
   // Invalidate the relocation information, as it will become invalid by the
   // code patching below, and is not needed any more.
   code->InvalidateRelocation();
 
   // For each return after a safepoint insert an absolute call to the
   // corresponding deoptimization entry.
+  ASSERT(patch_size() % Assembler::kInstrSize == 0);
+  int call_size_in_words = patch_size() / Assembler::kInstrSize;
   unsigned last_pc_offset = 0;
   SafepointTable table(function->code());
   for (unsigned i = 0; i < table.length(); i++) {
     unsigned pc_offset = table.GetPcOffset(i);
     SafepointEntry safepoint_entry = table.GetEntry(i);
     int deoptimization_index = safepoint_entry.deoptimization_index();
     int gap_code_size = safepoint_entry.gap_code_size();
     // Check that we did not shoot past next safepoint.
     // TODO(srdjan): How do we guarantee that safepoint code does not
     // overlap other safepoint patching code?
     CHECK(pc_offset >= last_pc_offset);
 #ifdef DEBUG
     // Destroy the code which is not supposed to be run again.
     int instructions = (pc_offset - last_pc_offset) / Assembler::kInstrSize;
     CodePatcher destroyer(code->instruction_start() + last_pc_offset,
                           instructions);
     for (int x = 0; x < instructions; x++) {
       destroyer.masm()->bkpt(0);
     }
 #endif
     last_pc_offset = pc_offset;
     if (deoptimization_index != Safepoint::kNoDeoptimizationIndex) {
-      const int kCallInstructionSizeInWords = 3;
-      CodePatcher patcher(code->instruction_start() + pc_offset + gap_code_size,
-                          kCallInstructionSizeInWords);
+      last_pc_offset += gap_code_size;
+      CodePatcher patcher(code->instruction_start() + last_pc_offset,
+                          call_size_in_words);
       Address deoptimization_entry = Deoptimizer::GetDeoptimizationEntry(
           deoptimization_index, Deoptimizer::LAZY);
       patcher.masm()->Call(deoptimization_entry, RelocInfo::NONE);
-      last_pc_offset +=
-          gap_code_size + kCallInstructionSizeInWords * Assembler::kInstrSize;
+      last_pc_offset += patch_size();
     }
   }
 
 
 #ifdef DEBUG
   // Destroy the code which is not supposed to be run again.
   int instructions =
       (code->safepoint_table_start() - last_pc_offset) / Assembler::kInstrSize;
   CodePatcher destroyer(code->instruction_start() + last_pc_offset,
                         instructions);
@@ skipping 404 matching lines @@
     __ push(ip);
     __ b(&done);
     ASSERT(masm()->pc_offset() - start == table_entry_size_);
   }
   __ bind(&done);
 }
 
 #undef __
 
 } }  // namespace v8::internal