Reapply "Lazy deopt without code patching."

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/become.h"
@@ skipping 14211 matching lines @@
   {
     uword size = Code::InstanceSize(pointer_offsets_length);
     RawObject* raw = Object::Allocate(Code::kClassId, size, Heap::kOld);
     NoSafepointScope no_safepoint;
     result ^= raw;
     result.set_pointer_offsets_length(pointer_offsets_length);
     result.set_is_optimized(false);
     result.set_is_alive(false);
     result.set_comments(Comments::New(0));
     result.set_compile_timestamp(0);
-    result.set_lazy_deopt_return_pc_offset(kInvalidPc);
-    result.set_lazy_deopt_throw_pc_offset(kInvalidPc);
     result.set_pc_descriptors(Object::empty_descriptors());
   }
   return result.raw();
 }
 
 
 RawCode* Code::FinalizeCode(const char* name,
                             Assembler* assembler,
                             bool optimized) {
   Isolate* isolate = Isolate::Current();
@@ skipping 293 matching lines @@
   // store buffer update is not needed here.
   StorePointer(&raw_ptr()->active_instructions_, instructions);
   StoreNonPointer(&raw_ptr()->entry_point_,
                   Instructions::UncheckedEntryPoint(instructions));
   StoreNonPointer(&raw_ptr()->checked_entry_point_,
                   Instructions::CheckedEntryPoint(instructions));
 #endif
 }
 
 
-uword Code::GetLazyDeoptReturnPc() const {
-  return (lazy_deopt_return_pc_offset() != kInvalidPc)
-      ? PayloadStart() + lazy_deopt_return_pc_offset() : 0;
-}
-
-
-uword Code::GetLazyDeoptThrowPc() const {
-  return (lazy_deopt_throw_pc_offset() != kInvalidPc)
-      ? PayloadStart() + lazy_deopt_throw_pc_offset() : 0;
-}
-
-
 RawStackmap* Code::GetStackmap(
     uint32_t pc_offset, Array* maps, Stackmap* map) const {
   // This code is used during iterating frames during a GC and hence it
   // should not in turn start a GC.
   NoSafepointScope no_safepoint;
   if (stackmaps() == Array::null()) {
     // No stack maps are present in the code object which means this
     // frame relies on tagged pointers.
     return Stackmap::null();
   }
@@ skipping 8448 matching lines @@
   return UserTag::null();
 }
 
 
 const char* UserTag::ToCString() const {
   const String& tag_label = String::Handle(label());
   return tag_label.ToCString();
 }
 
 }  // namespace dart