Refactor back edge table related code into a new class.

src/runtime.cc

 // Copyright 2012 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 8479 matching lines @@
   if (!function->IsOptimizable()) return isolate->heap()->undefined_value();
   function->MarkForLazyRecompilation();
 
   Code* unoptimized = function->shared()->code();
   if (args.length() == 2 &&
       unoptimized->kind() == Code::FUNCTION) {
     CONVERT_ARG_HANDLE_CHECKED(String, type, 1);
     if (type->IsOneByteEqualTo(STATIC_ASCII_VECTOR("osr"))) {
       // Start patching from the currently patched loop nesting level.
       int current_level = unoptimized->allow_osr_at_loop_nesting_level();
-      ASSERT(Deoptimizer::VerifyInterruptCode(
-                 isolate, unoptimized, current_level));
+      ASSERT(BackEdgeTable::Verify(isolate, unoptimized, current_level));
       for (int i = current_level + 1; i <= Code::kMaxLoopNestingMarker; i++) {
         unoptimized->set_allow_osr_at_loop_nesting_level(i);
         isolate->runtime_profiler()->AttemptOnStackReplacement(*function);
       }
     } else if (type->IsOneByteEqualTo(STATIC_ASCII_VECTOR("concurrent"))) {
       function->MarkForConcurrentRecompilation();
     }
   }
 
   return isolate->heap()->undefined_value();
@@ skipping 132 matching lines @@
     ASSERT(!ast_id.IsNone());
     if (FLAG_trace_osr) {
       PrintF("[OSR - replacing at AST id %d in ", ast_id.ToInt());
       function->PrintName();
       PrintF("]\n");
     }
     // Attempt OSR compilation.
     result = JSFunction::CompileOsr(function, ast_id, CLEAR_EXCEPTION);
   }
 
-  // Revert the patched interrupt now, regardless of whether OSR succeeds.
-  Deoptimizer::RevertInterruptCode(isolate, *unoptimized);
+  // Revert the patched back edge table, regardless of whether OSR succeeds.
+  BackEdgeTable::Revert(isolate, *unoptimized);
 
   // Check whether we ended up with usable optimized code.
   if (!result.is_null() && result->kind() == Code::OPTIMIZED_FUNCTION) {
     DeoptimizationInputData* data =
         DeoptimizationInputData::cast(result->deoptimization_data());
 
     if (data->OsrPcOffset()->value() >= 0) {
       ASSERT(BailoutId(data->OsrAstId()->value()) == ast_id);
       if (FLAG_trace_osr) {
         PrintF("[OSR - entry at AST id %d, offset %d in optimized code]\n",
@@ skipping 6132 matching lines @@
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     isolate->counters()->gc_last_resort_from_js()->Increment();
     isolate->heap()->CollectAllGarbage(Heap::kNoGCFlags,
                                        "Runtime::PerformGC");
   }
 }
 
 
 } }  // namespace v8::internal