Reapply "Lazy deopt without code patching."

runtime/vm/instructions_dbc.cc

 // Copyright (c) 2016, 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/globals.h"  // Needed here to get TARGET_ARCH_DBC.
 #if defined(TARGET_ARCH_DBC)
 
 #include "vm/instructions.h"
 #include "vm/instructions_dbc.h"
 
@@ skipping 49 matching lines @@
       ic_data_(ICData::Handle()) {
   ASSERT(code.ContainsInstructionAt(end_));
   const uword call_pc = end_ - sizeof(Instr);
   Instr call_instr = Bytecode::At(call_pc);
   ASSERT(Bytecode::IsCallOpcode(call_instr));
   ic_data_load_end_ = call_pc;
   target_code_pool_index_ = Bytecode::DecodeD(call_instr);
 }
 
 
-int CallPattern::DeoptCallPatternLengthInInstructions() {
-  UNIMPLEMENTED();
-  return 0;
-}
-
-
-int CallPattern::DeoptCallPatternLengthInBytes() {
-  UNIMPLEMENTED();
-  return 0;
-}
-
-
 NativeCallPattern::NativeCallPattern(uword pc, const Code& code)
     : object_pool_(ObjectPool::Handle(code.GetObjectPool())),
       end_(pc),
       native_function_pool_index_(-1),
       target_code_pool_index_(-1) {
   UNIMPLEMENTED();
 }
 
 
 RawCode* NativeCallPattern::target() const {
@@ skipping 82 matching lines @@
   return reinterpret_cast<RawCode*>(
       object_pool_.ObjectAt(target_code_pool_index_));
 }
 
 
 void CallPattern::SetTargetCode(const Code& target_code) const {
   object_pool_.SetObjectAt(target_code_pool_index_, target_code);
 }
 
 
-void CallPattern::InsertDeoptCallAt(uword pc, uword target_address) {
+void CallPattern::InsertDeoptCallAt(uword pc) {
   const uint8_t argc = Bytecode::IsCallOpcode(Bytecode::At(pc)) ?
       Bytecode::DecodeArgc(Bytecode::At(pc)) : 0;
   *reinterpret_cast<Instr*>(pc) = Bytecode::Encode(Bytecode::kDeopt, argc, 0);
 }
 
 
 SwitchableCallPattern::SwitchableCallPattern(uword pc, const Code& code)
     : object_pool_(ObjectPool::Handle(code.GetObjectPool())),
       data_pool_index_(-1),
       target_pool_index_(-1) {
@@ skipping 30 matching lines @@
 
 
 bool ReturnPattern::IsValid() const {
   UNIMPLEMENTED();
   return false;
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_DBC