[GetIsolate] Return raw object for bytecode constants

Return the raw Object* when accessing the constant pool of bytecode
with the bytecode array accessor, to avoid needing an isolate there.
If the returned value needs to be a handle, we create the handle
later.

Bug: v8:7786
Change-Id: Ifeac2a06f0383230bf7e9bfc1b751d9750ecfb51
Reviewed-on: https://chromium-review.googlesource.com/1102334
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53784}

src/interpreter/bytecode-array-accessor.cc

@@ -184,12 +184,11 @@ Runtime::FunctionId BytecodeArrayAccessor::GetIntrinsicIdOperand(
       static_cast<IntrinsicsHelper::IntrinsicId>(raw_id));
 }
 
-Handle<Object> BytecodeArrayAccessor::GetConstantAtIndex(int index) const {
-  return FixedArray::get(bytecode_array()->constant_pool(), index,
-                         bytecode_array()->GetIsolate());
+Object* BytecodeArrayAccessor::GetConstantAtIndex(int index) const {
+  return bytecode_array()->constant_pool()->get(index);
 }
 
-Handle<Object> BytecodeArrayAccessor::GetConstantForIndexOperand(
+Object* BytecodeArrayAccessor::GetConstantForIndexOperand(
     int operand_index) const {
   return GetConstantAtIndex(GetIndexOperand(operand_index));
 }
@@ -203,7 +202,7 @@ int BytecodeArrayAccessor::GetJumpTargetOffset() const {
     }
     return GetAbsoluteOffset(relative_offset);
   } else if (interpreter::Bytecodes::IsJumpConstant(bytecode)) {
-    Smi* smi = Smi::cast(*GetConstantForIndexOperand(0));
+    Smi* smi = Smi::cast(GetConstantForIndexOperand(0));
     return GetAbsoluteOffset(smi->value());
   } else {
     UNREACHABLE();
@@ -273,6 +272,7 @@ JumpTableTargetOffsets::iterator::iterator(
     int case_value, int table_offset, int table_end,
     const BytecodeArrayAccessor* accessor)
     : accessor_(accessor),
+      current_(Smi::kZero),
       index_(case_value),
       table_offset_(table_offset),
       table_end_(table_end) {
@@ -281,8 +281,7 @@ JumpTableTargetOffsets::iterator::iterator(
 
 JumpTableTargetOffset JumpTableTargetOffsets::iterator::operator*() {
   DCHECK_LT(table_offset_, table_end_);
-  DCHECK(current_->IsSmi());
-  return {index_, accessor_->GetAbsoluteOffset(Smi::ToInt(*current_))};
+  return {index_, accessor_->GetAbsoluteOffset(Smi::ToInt(current_))};
 }
 
 JumpTableTargetOffsets::iterator& JumpTableTargetOffsets::iterator::
@@ -305,13 +304,17 @@ bool JumpTableTargetOffsets::iterator::operator!=(
 void JumpTableTargetOffsets::iterator::UpdateAndAdvanceToValid() {
   if (table_offset_ >= table_end_) return;
 
-  current_ = accessor_->GetConstantAtIndex(table_offset_);
-  Isolate* isolate = accessor_->bytecode_array()->GetIsolate();
-  while (current_->IsTheHole(isolate)) {
+  Object* current = accessor_->GetConstantAtIndex(table_offset_);
+  while (!current->IsSmi()) {
+    DCHECK(current->IsTheHole());
     ++table_offset_;
     ++index_;
     if (table_offset_ >= table_end_) break;
-    current_ = accessor_->GetConstantAtIndex(table_offset_);
+    current = accessor_->GetConstantAtIndex(table_offset_);
+  }
+  // Make sure we haven't reached the end of the table with a hole in current.
+  if (current->IsSmi()) {
+    current_ = Smi::cast(current);
   }
 }
 

src/interpreter/bytecode-array-accessor.h

@@ -42,7 +42,7 @@ class V8_EXPORT_PRIVATE JumpTableTargetOffsets final {
     void UpdateAndAdvanceToValid();
 
     const BytecodeArrayAccessor* accessor_;
-    Handle<Object> current_;
+    Smi* current_;
     int index_;
     int table_offset_;
     int table_end_;
@@ -90,8 +90,8 @@ class V8_EXPORT_PRIVATE BytecodeArrayAccessor {
   Runtime::FunctionId GetRuntimeIdOperand(int operand_index) const;
   Runtime::FunctionId GetIntrinsicIdOperand(int operand_index) const;
   uint32_t GetNativeContextIndexOperand(int operand_index) const;
-  Handle<Object> GetConstantAtIndex(int offset) const;
-  Handle<Object> GetConstantForIndexOperand(int operand_index) const;
+  Object* GetConstantAtIndex(int offset) const;
+  Object* GetConstantForIndexOperand(int operand_index) const;
 
   // Returns the absolute offset of the branch target at the current bytecode.
   // It is an error to call this method if the bytecode is not for a jump or

test/unittests/interpreter/bytecode-array-builder-unittest.cc

@@ -630,7 +630,7 @@ TEST_F(BytecodeArrayBuilderTest, ForwardJumps) {
   iterator.Advance();
 
   CHECK_EQ(iterator.current_bytecode(), Bytecode::kJumpConstant);
-  CHECK_EQ(*iterator.GetConstantForIndexOperand(0),
+  CHECK_EQ(iterator.GetConstantForIndexOperand(0),
            Smi::FromInt(kFarJumpDistance));
   iterator.Advance();
 
@@ -638,7 +638,7 @@ TEST_F(BytecodeArrayBuilderTest, ForwardJumps) {
   iterator.Advance();
 
   CHECK_EQ(iterator.current_bytecode(), Bytecode::kJumpIfTrueConstant);
-  CHECK_EQ(*iterator.GetConstantForIndexOperand(0),
+  CHECK_EQ(iterator.GetConstantForIndexOperand(0),
            Smi::FromInt(kFarJumpDistance - 5));
   iterator.Advance();
 
@@ -646,7 +646,7 @@ TEST_F(BytecodeArrayBuilderTest, ForwardJumps) {
   iterator.Advance();
 
   CHECK_EQ(iterator.current_bytecode(), Bytecode::kJumpIfFalseConstant);
-  CHECK_EQ(*iterator.GetConstantForIndexOperand(0),
+  CHECK_EQ(iterator.GetConstantForIndexOperand(0),
            Smi::FromInt(kFarJumpDistance - 10));
   iterator.Advance();
 
@@ -654,7 +654,7 @@ TEST_F(BytecodeArrayBuilderTest, ForwardJumps) {
   iterator.Advance();
 
   CHECK_EQ(iterator.current_bytecode(), Bytecode::kJumpIfToBooleanTrueConstant);
-  CHECK_EQ(*iterator.GetConstantForIndexOperand(0),
+  CHECK_EQ(iterator.GetConstantForIndexOperand(0),
            Smi::FromInt(kFarJumpDistance - 15));
   iterator.Advance();
 
@@ -663,7 +663,7 @@ TEST_F(BytecodeArrayBuilderTest, ForwardJumps) {
 
   CHECK_EQ(iterator.current_bytecode(),
            Bytecode::kJumpIfToBooleanFalseConstant);
-  CHECK_EQ(*iterator.GetConstantForIndexOperand(0),
+  CHECK_EQ(iterator.GetConstantForIndexOperand(0),
            Smi::FromInt(kFarJumpDistance - 20));
   iterator.Advance();
 }