[Interpreter] Optimize BytecodeArrayBuilder and BytecodeArrayWriter.

src/interpreter/bytecode-peephole-optimizer.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/interpreter/bytecode-peephole-optimizer.h"
 
 #include "src/objects-inl.h"
 #include "src/objects.h"
 
 namespace v8 {
 namespace internal {
 namespace interpreter {
 
 BytecodePeepholeOptimizer::BytecodePeepholeOptimizer(
     BytecodePipelineStage* next_stage)
-    : next_stage_(next_stage) {
+    : next_stage_(next_stage), last_(Bytecode::kIllegal) {
   InvalidateLast();
 }
 
 // override
 Handle<BytecodeArray> BytecodePeepholeOptimizer::ToBytecodeArray(
-    Isolate* isolate, int fixed_register_count, int parameter_count,
+    Isolate* isolate, int register_count, int parameter_count,
     Handle<FixedArray> handler_table) {
   Flush();
-  return next_stage_->ToBytecodeArray(isolate, fixed_register_count,
-                                      parameter_count, handler_table);
+  return next_stage_->ToBytecodeArray(isolate, register_count, parameter_count,
+                                      handler_table);
 }
 
 // override
 void BytecodePeepholeOptimizer::BindLabel(BytecodeLabel* label) {
   Flush();
   next_stage_->BindLabel(label);
 }
 
 // override
 void BytecodePeepholeOptimizer::BindLabel(const BytecodeLabel& target,
@@ skipping 98 matching lines @@
   current->set_bytecode(Bytecode::kLdar, current->operand(0));
 }
 
 void TransformLdaSmiBinaryOpToBinaryOpWithSmi(Bytecode new_bytecode,
                                               BytecodeNode* const last,
                                               BytecodeNode* const current) {
   DCHECK_EQ(last->bytecode(), Bytecode::kLdaSmi);
   current->set_bytecode(new_bytecode, last->operand(0), current->operand(0),
                         current->operand(1));
   if (last->source_info().is_valid()) {
-    current->source_info().Clone(last->source_info());
+    current->source_info_ptr()->Clone(last->source_info());
   }
 }
 
 void TransformLdaZeroBinaryOpToBinaryOpWithZero(Bytecode new_bytecode,
                                                 BytecodeNode* const last,
                                                 BytecodeNode* const current) {
   DCHECK_EQ(last->bytecode(), Bytecode::kLdaZero);
   current->set_bytecode(new_bytecode, 0, current->operand(0),
                         current->operand(1));
   if (last->source_info().is_valid()) {
-    current->source_info().Clone(last->source_info());
+    current->source_info_ptr()->Clone(last->source_info());
   }
 }
 
 }  // namespace
 
 void BytecodePeepholeOptimizer::DefaultAction(
     BytecodeNode* const node, const PeepholeActionAndData* action_data) {
   DCHECK(LastIsValid());
   DCHECK(!Bytecodes::IsJump(node->bytecode()));
 
@@ skipping 49 matching lines @@
 void BytecodePeepholeOptimizer::ElideLastAction(
     BytecodeNode* const node, const PeepholeActionAndData* action_data) {
   DCHECK(LastIsValid());
   DCHECK(!Bytecodes::IsJump(node->bytecode()));
 
   if (CanElideLastBasedOnSourcePosition(node)) {
     if (last()->source_info().is_valid()) {
       // |node| can not have a valid source position if the source
       // position of last() is valid (per rules in
       // CanElideLastBasedOnSourcePosition()).
-      node->source_info().Clone(last()->source_info());
+      node->source_info_ptr()->Clone(last()->source_info());
     }
     SetLast(node);
   } else {
     DefaultAction(node);
   }
 }
 
 void BytecodePeepholeOptimizer::ChangeBytecodeAction(
     BytecodeNode* const node, const PeepholeActionAndData* action_data) {
   DCHECK(LastIsValid());
@@ skipping 70 matching lines @@
 }
 
 void BytecodePeepholeOptimizer::ElideLastBeforeJumpAction(
     BytecodeNode* const node, const PeepholeActionAndData* action_data) {
   DCHECK(LastIsValid());
   DCHECK(Bytecodes::IsJump(node->bytecode()));
 
   if (!CanElideLastBasedOnSourcePosition(node)) {
     next_stage()->Write(last());
   } else if (!node->source_info().is_valid()) {
-    node->source_info().Clone(last()->source_info());
+    node->source_info_ptr()->Clone(last()->source_info());
   }
   InvalidateLast();
 }
 
 void BytecodePeepholeOptimizer::ApplyPeepholeAction(BytecodeNode* const node) {
   // A single table is used for looking up peephole optimization
   // matches as it is observed to have better performance. This is
   // inspite of the fact that jump bytecodes and non-jump bytecodes
   // have different processing logic, in particular a jump bytecode
   // always needs to emit the jump via WriteJump().
   const PeepholeActionAndData* const action_data =
       PeepholeActionTable::Lookup(last()->bytecode(), node->bytecode());
   switch (action_data->action) {
 #define CASE(Action)              \
   case PeepholeAction::k##Action: \
     Action(node, action_data);    \
     break;
     PEEPHOLE_ACTION_LIST(CASE)
 #undef CASE
     default:
       UNREACHABLE();
       break;
   }
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8