[wasm] Remove obsolete {Code::has_tagged_params} field.

Now that all WebAssembly code (including its lazy compile stub) has been
moved off the garbage-collected heap, we can determine the taggedness of
parameters purely from the {Code::Kind} and no longer need a dedicated
flag for it.

R=clemensh@chromium.org
BUG=v8:6792

Change-Id: If40b6763d042c19b937391fac8301a03b8ccc891
Reviewed-on: https://chromium-review.googlesource.com/999416Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52433}

src/builtins/builtins-definitions.h

@@ -1319,8 +1319,6 @@ namespace internal {
   BUILTIN_LIST(IGNORE_BUILTIN, IGNORE_BUILTIN, IGNORE_BUILTIN, V, \
                IGNORE_BUILTIN, IGNORE_BUILTIN, IGNORE_BUILTIN)
 
-#define BUILTINS_WITH_UNTAGGED_PARAMS(V) V(WasmCompileLazy)
-
 }  // namespace internal
 }  // namespace v8
 

src/builtins/setup-builtins-internal.cc

@@ -285,17 +285,6 @@ void SetupIsolateDelegate::SetupBuiltinsInternal(Isolate* isolate) {
   BUILTIN_EXCEPTION_CAUGHT_PREDICTION_LIST(SET_EXCEPTION_CAUGHT_PREDICTION)
 #undef SET_EXCEPTION_CAUGHT_PREDICTION
 
-  // TODO(mstarzinger,6792): This code-space modification section should be
-  // moved into {Heap} eventually and a safe wrapper be provided.
-  CodeSpaceMemoryModificationScope modification_scope(isolate->heap());
-
-#define SET_CODE_NON_TAGGED_PARAMS(Name)             \
-  Code::cast(builtins->builtins_[Builtins::k##Name]) \
-      ->set_has_tagged_params(false);
-
-  BUILTINS_WITH_UNTAGGED_PARAMS(SET_CODE_NON_TAGGED_PARAMS)
-#undef SET_CODE_NON_TAGGED_PARAMS
-
   builtins->MarkInitialized();
 }
 

src/factory.cc

@@ -1873,7 +1873,6 @@ Handle<Code> Factory::NewOffHeapTrampolineFor(Handle<Code> code,
   result->initialize_flags(code->kind(), code->has_unwinding_info(),
                            code->is_turbofanned(), stack_slots);
   result->set_builtin_index(code->builtin_index());
-  result->set_has_tagged_params(code->has_tagged_params());
   result->set_handler_table_offset(code->handler_table_offset());
   result->code_data_container()->set_kind_specific_flags(
       code->code_data_container()->kind_specific_flags());

src/heap/heap.cc

@@ -3348,26 +3348,12 @@ AllocationResult Heap::AllocateCode(
   code->set_safepoint_table_offset(safepoint_table_offset);
   code->set_handler_table_offset(handler_table_offset);
   code->set_code_data_container(data_container);
-  code->set_has_tagged_params(true);
   code->set_deoptimization_data(deopt_data);
   code->set_stub_key(stub_key);
   code->set_source_position_table(source_position_table);
   code->set_constant_pool_offset(desc.instr_size - desc.constant_pool_size);
   code->set_builtin_index(builtin_index);
 
-  switch (code->kind()) {
-    case Code::OPTIMIZED_FUNCTION:
-      code->set_marked_for_deoptimization(false);
-      break;
-    case Code::JS_TO_WASM_FUNCTION:
-    case Code::C_WASM_ENTRY:
-    case Code::WASM_FUNCTION:
-      code->set_has_tagged_params(false);
-      break;
-    default:
-      break;
-  }
-
   // Allow self references to created code object by patching the handle to
   // point to the newly allocated Code object.
   if (!self_ref.is_null()) *(self_ref.location()) = code;

src/objects/code-inl.h

@@ -359,19 +359,13 @@ inline bool Code::checks_optimization_marker() const {
          (kind() == OPTIMIZED_FUNCTION && marked_for_deoptimization());
 }
 
-inline bool Code::has_unwinding_info() const {
-  return HasUnwindingInfoField::decode(READ_UINT32_FIELD(this, kFlagsOffset));
-}
-
 inline bool Code::has_tagged_params() const {
-  int flags = READ_UINT32_FIELD(this, kFlagsOffset);
-  return HasTaggedStackField::decode(flags);
+  return kind() != JS_TO_WASM_FUNCTION && kind() != C_WASM_ENTRY &&
+         kind() != WASM_FUNCTION;
 }
 
-inline void Code::set_has_tagged_params(bool value) {
-  int previous = READ_UINT32_FIELD(this, kFlagsOffset);
-  int updated = HasTaggedStackField::update(previous, value);
-  WRITE_UINT32_FIELD(this, kFlagsOffset, updated);
+inline bool Code::has_unwinding_info() const {
+  return HasUnwindingInfoField::decode(READ_UINT32_FIELD(this, kFlagsOffset));
 }
 
 inline bool Code::is_turbofanned() const {

src/objects/code.h

@@ -116,10 +116,8 @@ class Code : public HeapObject {
   // feedback vector.
   inline bool checks_optimization_marker() const;
 
-  // [has_tagged_params]: For compiled code or builtins: Tells whether the
-  // outgoing parameters of this code are tagged pointers. True for other kinds.
+  // Tells whether the outgoing parameters of this code are tagged pointers.
   inline bool has_tagged_params() const;
-  inline void set_has_tagged_params(bool value);
 
   // [is_turbofanned]: For kind STUB or OPTIMIZED_FUNCTION, tells whether the
   // code object was generated by the TurboFan optimizing compiler.
@@ -403,7 +401,6 @@ class Code : public HeapObject {
 #define CODE_FLAGS_BIT_FIELDS(V, _)    \
   V(HasUnwindingInfoField, bool, 1, _) \
   V(KindField, Kind, 5, _)             \
-  V(HasTaggedStackField, bool, 1, _)   \
   V(IsTurbofannedField, bool, 1, _)    \
   V(StackSlotsField, int, 24, _)
   DEFINE_BIT_FIELDS(CODE_FLAGS_BIT_FIELDS)

src/wasm/module-compiler.cc

@@ -1361,14 +1361,11 @@ MaybeHandle<WasmModuleObject> CompileToModuleObjectInternal(
       script, asm_js_offset_table);
   if (lazy_compile) WasmSharedModuleData::PrepareForLazyCompilation(shared);
 
-  Handle<Code> init_builtin = lazy_compile
-                                  ? BUILTIN_CODE(isolate, WasmCompileLazy)
-                                  : BUILTIN_CODE(isolate, Illegal);
-
   int export_wrappers_size =
       static_cast<int>(wasm_module->num_exported_functions);
   Handle<FixedArray> export_wrappers =
       factory->NewFixedArray(static_cast<int>(export_wrappers_size), TENURED);
+  Handle<Code> init_builtin = BUILTIN_CODE(isolate, Illegal);
   for (int i = 0, e = export_wrappers->length(); i < e; ++i) {
     export_wrappers->set(i, *init_builtin);
   }