[compiler] Rename Instruction::kEnableSerialization

The option to "enable serialization" actually only enables the
roots-relative register addressing. In the spirit of expressing specific
behaviors rather than isolate-wide modes, rename this flag to what
it actually does.

R=bmeurer@chromium.org

Change-Id: Iacbad8064c8f38b364db2a0bdd0e83ef4a265867
Reviewed-on: https://chromium-review.googlesource.com/1113742Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54016}

src/compiler/instruction-selector.cc

@@ -27,7 +27,7 @@ InstructionSelector::InstructionSelector(
     EnableSwitchJumpTable enable_switch_jump_table,
     SourcePositionMode source_position_mode, Features features,
     EnableScheduling enable_scheduling,
-    EnableSerialization enable_serialization,
+    EnableRootsRelativeAddressing enable_roots_relative_addressing,
     PoisoningMitigationLevel poisoning_level, EnableTraceTurboJson trace_turbo)
     : zone_(zone),
       linkage_(linkage),
@@ -48,7 +48,7 @@ InstructionSelector::InstructionSelector(
       virtual_register_rename_(zone),
       scheduler_(nullptr),
       enable_scheduling_(enable_scheduling),
-      enable_serialization_(enable_serialization),
+      enable_roots_relative_addressing_(enable_roots_relative_addressing),
       enable_switch_jump_table_(enable_switch_jump_table),
       poisoning_level_(poisoning_level),
       frame_(frame),
@@ -420,7 +420,7 @@ void InstructionSelector::SetEffectLevel(Node* node, int effect_level) {
 }
 
 bool InstructionSelector::CanAddressRelativeToRootsRegister() const {
-  return enable_serialization_ == kDisableSerialization &&
+  return enable_roots_relative_addressing_ == kEnableRootsRelativeAddressing &&
          CanUseRootsRegister();
 }
 

src/compiler/instruction-selector.h

@@ -251,7 +251,10 @@ class V8_EXPORT_PRIVATE InstructionSelector final {
 
   enum SourcePositionMode { kCallSourcePositions, kAllSourcePositions };
   enum EnableScheduling { kDisableScheduling, kEnableScheduling };
-  enum EnableSerialization { kDisableSerialization, kEnableSerialization };
+  enum EnableRootsRelativeAddressing {
+    kDisableRootsRelativeAddressing,
+    kEnableRootsRelativeAddressing
+  };
   enum EnableSwitchJumpTable {
     kDisableSwitchJumpTable,
     kEnableSwitchJumpTable
@@ -268,7 +271,8 @@ class V8_EXPORT_PRIVATE InstructionSelector final {
       EnableScheduling enable_scheduling = FLAG_turbo_instruction_scheduling
                                                ? kEnableScheduling
                                                : kDisableScheduling,
-      EnableSerialization enable_serialization = kDisableSerialization,
+      EnableRootsRelativeAddressing enable_roots_relative_addressing =
+          kDisableRootsRelativeAddressing,
       PoisoningMitigationLevel poisoning_level =
           PoisoningMitigationLevel::kDontPoison,
       EnableTraceTurboJson trace_turbo = kDisableTraceTurboJson);
@@ -433,8 +437,7 @@ class V8_EXPORT_PRIVATE InstructionSelector final {
   const std::map<NodeId, int> GetVirtualRegistersForTesting() const;
 
   // Check if we can generate loads and stores of ExternalConstants relative
-  // to the roots register, i.e. if both a root register is available for this
-  // compilation unit and the serializer is disabled.
+  // to the roots register.
   bool CanAddressRelativeToRootsRegister() const;
   // Check if we can use the roots register to access GC roots.
   bool CanUseRootsRegister() const;
@@ -706,7 +709,7 @@ class V8_EXPORT_PRIVATE InstructionSelector final {
   IntVector virtual_register_rename_;
   InstructionScheduler* scheduler_;
   EnableScheduling enable_scheduling_;
-  EnableSerialization enable_serialization_;
+  EnableRootsRelativeAddressing enable_roots_relative_addressing_;
   EnableSwitchJumpTable enable_switch_jump_table_;
 
   PoisoningMitigationLevel poisoning_level_;

src/compiler/pipeline.cc

@@ -1646,8 +1646,8 @@ struct InstructionSelectionPhase {
             ? InstructionSelector::kEnableScheduling
             : InstructionSelector::kDisableScheduling,
         data->isolate()->serializer_enabled()
-            ? InstructionSelector::kEnableSerialization
-            : InstructionSelector::kDisableSerialization,
+            ? InstructionSelector::kDisableRootsRelativeAddressing
+            : InstructionSelector::kEnableRootsRelativeAddressing,
         data->info()->GetPoisoningMitigationLevel(),
         data->info()->trace_turbo_json_enabled()
             ? InstructionSelector::kEnableTraceTurboJson

test/unittests/compiler/instruction-selector-unittest.cc

@@ -41,12 +41,12 @@ InstructionSelectorTest::Stream InstructionSelectorTest::StreamBuilder::Build(
   InstructionSequence sequence(test_->isolate(), test_->zone(),
                                instruction_blocks);
   SourcePositionTable source_position_table(graph());
-  InstructionSelector selector(test_->zone(), node_count, &linkage, &sequence,
-                               schedule, &source_position_table, nullptr,
-                               InstructionSelector::kEnableSwitchJumpTable,
-                               source_position_mode, features,
-                               InstructionSelector::kDisableScheduling,
-                               InstructionSelector::kDisableSerialization,
+  InstructionSelector selector(
+      test_->zone(), node_count, &linkage, &sequence, schedule,
+      &source_position_table, nullptr,
+      InstructionSelector::kEnableSwitchJumpTable, source_position_mode,
+      features, InstructionSelector::kDisableScheduling,
+      InstructionSelector::kEnableRootsRelativeAddressing,
       PoisoningMitigationLevel::kPoisonAll);
   selector.SelectInstructions();
   if (FLAG_trace_turbo) {