[heap] Introduce {Movability} enum for type safety.

R=mlippautz@chromium.org

Change-Id: Ie5ff0347d7c849e1941f8c8237a0bd56fdb68a4e
Reviewed-on: https://chromium-review.googlesource.com/768672Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49372}

src/arm/code-stubs-arm.cc

@@ -220,10 +220,7 @@ void MathPowStub::Generate(MacroAssembler* masm) {
   __ Ret();
 }
 
-bool CEntryStub::NeedsImmovableCode() {
-  return true;
-}
-
+Movability CEntryStub::NeedsImmovableCode() { return kImmovable; }
 
 void CodeStub::GenerateStubsAheadOfTime(Isolate* isolate) {
   CEntryStub::GenerateAheadOfTime(isolate);

src/arm/code-stubs-arm.h

@@ -19,7 +19,7 @@ class DirectCEntryStub: public PlatformCodeStub {
   void GenerateCall(MacroAssembler* masm, Register target);
 
  private:
-  bool NeedsImmovableCode() override { return true; }
+  Movability NeedsImmovableCode() override { return kImmovable; }
 
   DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
   DEFINE_PLATFORM_CODE_STUB(DirectCEntry, PlatformCodeStub);

src/arm64/code-stubs-arm64.cc

@@ -235,8 +235,7 @@ void CodeStub::GenerateFPStubs(Isolate* isolate) {
   USE(isolate);
 }
 
-
-bool CEntryStub::NeedsImmovableCode() {
+Movability CEntryStub::NeedsImmovableCode() {
   // CEntryStub stores the return address on the stack before calling into
   // C++ code. In some cases, the VM accesses this address, but it is not used
   // when the C++ code returns to the stub because LR holds the return address
@@ -245,7 +244,7 @@ bool CEntryStub::NeedsImmovableCode() {
   // TODO(jbramley): Whilst this is the only analysis that makes sense, I can't
   // find any comment to confirm this, and I don't hit any crashes whatever
   // this function returns. The anaylsis should be properly confirmed.
-  return true;
+  return kImmovable;
 }
 
 

src/arm64/code-stubs-arm64.h

@@ -16,7 +16,7 @@ class DirectCEntryStub: public PlatformCodeStub {
   void GenerateCall(MacroAssembler* masm, Register target);
 
  private:
-  bool NeedsImmovableCode() override { return true; }
+  Movability NeedsImmovableCode() override { return kImmovable; }
 
   DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
   DEFINE_PLATFORM_CODE_STUB(DirectCEntry, PlatformCodeStub);

src/code-stubs.h

@@ -194,7 +194,7 @@ class CodeStub : public ZoneObject {
 
   // Returns whether the code generated for this stub needs to be allocated as
   // a fixed (non-moveable) code object.
-  virtual bool NeedsImmovableCode() { return false; }
+  virtual Movability NeedsImmovableCode() { return kMovable; }
 
   virtual void PrintName(std::ostream& os) const;        // NOLINT
   virtual void PrintBaseName(std::ostream& os) const;    // NOLINT
@@ -693,7 +693,7 @@ class CEntryStub : public PlatformCodeStub {
   bool is_builtin_exit() const { return FrameTypeBits::decode(minor_key_); }
   int result_size() const { return ResultSizeBits::decode(minor_key_); }
 
-  bool NeedsImmovableCode() override;
+  Movability NeedsImmovableCode() override;
 
   class SaveDoublesBits : public BitField<bool, 0, 1> {};
   class ArgvMode : public BitField<bool, 1, 1> {};

src/compiler/code-generator.cc

@@ -317,7 +317,7 @@ Handle<Code> CodeGenerator::FinalizeCode() {
 
   Handle<Code> result = isolate()->factory()->NewCode(
       desc, info()->code_kind(), Handle<Object>(), table, source_positions,
-      deopt_data, false, info()->stub_key(), true,
+      deopt_data, kMovable, info()->stub_key(), true,
       frame()->GetTotalFrameSlotCount(), safepoints()->GetCodeOffset());
   isolate()->counters()->total_compiled_code_size()->Increment(
       result->instruction_size());

src/deoptimizer.cc

@@ -1794,7 +1794,7 @@ void Deoptimizer::EnsureCodeForDeoptimizationEntry(Isolate* isolate,
   // directly and there is no support for relocating them.
   Handle<Code> code = isolate->factory()->NewCode(
       desc, Code::STUB, Handle<Object>(), MaybeHandle<HandlerTable>(),
-      MaybeHandle<ByteArray>(), MaybeHandle<DeoptimizationData>(), true);
+      MaybeHandle<ByteArray>(), MaybeHandle<DeoptimizationData>(), kImmovable);
   CHECK(Heap::IsImmovable(*code));
 
   CHECK_NULL(data->deopt_entry_code_[type]);

src/factory.cc

@@ -1792,9 +1792,9 @@ Handle<CodeDataContainer> Factory::NewCodeDataContainer(int flags) {
   return data_container;
 }
 
-Handle<Code> Factory::NewCodeRaw(int object_size, bool immovable) {
+Handle<Code> Factory::NewCodeRaw(int object_size, Movability movability) {
   CALL_HEAP_FUNCTION(isolate(),
-                     isolate()->heap()->AllocateCode(object_size, immovable),
+                     isolate()->heap()->AllocateCode(object_size, movability),
                      Code);
 }
 
@@ -1802,7 +1802,7 @@ Handle<Code> Factory::NewCode(
     const CodeDesc& desc, Code::Kind kind, Handle<Object> self_ref,
     MaybeHandle<HandlerTable> maybe_handler_table,
     MaybeHandle<ByteArray> maybe_source_position_table,
-    MaybeHandle<DeoptimizationData> maybe_deopt_data, bool immovable,
+    MaybeHandle<DeoptimizationData> maybe_deopt_data, Movability movability,
     uint32_t stub_key, bool is_turbofanned, int stack_slots,
     int safepoint_table_offset) {
   Handle<ByteArray> reloc_info = NewByteArray(desc.reloc_size, TENURED);
@@ -1833,7 +1833,7 @@ Handle<Code> Factory::NewCode(
   int obj_size = Code::SizeFor(RoundUp(body_size, kObjectAlignment));
 
   CodeSpaceMemoryModificationScope code_allocation(isolate()->heap());
-  Handle<Code> code = NewCodeRaw(obj_size, immovable);
+  Handle<Code> code = NewCodeRaw(obj_size, movability);
   DCHECK(!isolate()->heap()->memory_allocator()->code_range()->valid() ||
          isolate()->heap()->memory_allocator()->code_range()->contains(
              code->address()) ||
@@ -1893,8 +1893,7 @@ Handle<Code> Factory::NewCode(
 }
 
 Handle<Code> Factory::NewCodeForDeserialization(uint32_t size) {
-  const bool kNotImmovable = false;
-  return NewCodeRaw(size, kNotImmovable);
+  return NewCodeRaw(size, kMovable);
 }
 
 Handle<Code> Factory::CopyCode(Handle<Code> code) {

src/factory.h

@@ -678,7 +678,7 @@ class V8_EXPORT_PRIVATE Factory final {
                            MaybeHandle<ByteArray>(),
                        MaybeHandle<DeoptimizationData> maybe_deopt_data =
                            MaybeHandle<DeoptimizationData>(),
-                       bool immovable = false, uint32_t stub_key = 0,
+                       Movability movability = kMovable, uint32_t stub_key = 0,
                        bool is_turbofanned = false, int stack_slots = 0,
                        int safepoint_table_offset = 0);
 
@@ -853,7 +853,7 @@ class V8_EXPORT_PRIVATE Factory final {
                                            PretenureFlag pretenure);
 
   // Creates a code object that is not yet fully initialized yet.
-  Handle<Code> NewCodeRaw(int object_size, bool immovable);
+  Handle<Code> NewCodeRaw(int object_size, Movability movability);
 
   // Attempt to find the number in a small cache.  If we finds it, return
   // the string representation of the number.  Otherwise return undefined.

src/globals.h

@@ -617,6 +617,8 @@ enum GarbageCollector { SCAVENGER, MARK_COMPACTOR, MINOR_MARK_COMPACTOR };
 
 enum Executability { NOT_EXECUTABLE, EXECUTABLE };
 
+enum Movability { kMovable, kImmovable };
+
 enum VisitMode {
   VISIT_ALL,
   VISIT_ALL_IN_MINOR_MC_MARK,

src/heap/heap.cc

@@ -3066,14 +3066,13 @@ AllocationResult Heap::AllocateFixedTypedArray(int length,
   return elements;
 }
 
-
-AllocationResult Heap::AllocateCode(int object_size, bool immovable) {
+AllocationResult Heap::AllocateCode(int object_size, Movability movability) {
   DCHECK(IsAligned(static_cast<intptr_t>(object_size), kCodeAlignment));
   AllocationResult allocation = AllocateRaw(object_size, CODE_SPACE);
 
   HeapObject* result = nullptr;
   if (!allocation.To(&result)) return allocation;
-  if (immovable) {
+  if (movability == kImmovable) {
     Address address = result->address();
     MemoryChunk* chunk = MemoryChunk::FromAddress(address);
     // Code objects which should stay at a fixed address are allocated either

src/heap/heap.h

@@ -2216,8 +2216,8 @@ class Heap {
   MUST_USE_RESULT AllocationResult
       AllocateForeign(Address address, PretenureFlag pretenure = NOT_TENURED);
 
-  MUST_USE_RESULT AllocationResult
-      AllocateCode(int object_size, bool immovable);
+  MUST_USE_RESULT AllocationResult AllocateCode(int object_size,
+                                                Movability movability);
 
   void set_force_oom(bool value) { force_oom_ = value; }
 

src/ia32/code-stubs-ia32.cc

@@ -283,11 +283,7 @@ void MathPowStub::Generate(MacroAssembler* masm) {
   __ ret(0);
 }
 
-
-bool CEntryStub::NeedsImmovableCode() {
-  return false;
-}
-
+Movability CEntryStub::NeedsImmovableCode() { return kMovable; }
 
 void CodeStub::GenerateStubsAheadOfTime(Isolate* isolate) {
   CEntryStub::GenerateAheadOfTime(isolate);

src/mips/code-stubs-mips.cc

@@ -287,10 +287,7 @@ void MathPowStub::Generate(MacroAssembler* masm) {
   __ Ret();
 }
 
-bool CEntryStub::NeedsImmovableCode() {
-  return true;
-}
-
+Movability CEntryStub::NeedsImmovableCode() { return kImmovable; }
 
 void CodeStub::GenerateStubsAheadOfTime(Isolate* isolate) {
   CEntryStub::GenerateAheadOfTime(isolate);

src/mips/code-stubs-mips.h

@@ -19,7 +19,7 @@ class DirectCEntryStub: public PlatformCodeStub {
   void GenerateCall(MacroAssembler* masm, Register target);
 
  private:
-  bool NeedsImmovableCode() override { return true; }
+  Movability NeedsImmovableCode() override { return kImmovable; }
 
   DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
   DEFINE_PLATFORM_CODE_STUB(DirectCEntry, PlatformCodeStub);

src/mips64/code-stubs-mips64.cc

@@ -286,10 +286,7 @@ void MathPowStub::Generate(MacroAssembler* masm) {
   __ Ret();
 }
 
-bool CEntryStub::NeedsImmovableCode() {
-  return true;
-}
-
+Movability CEntryStub::NeedsImmovableCode() { return kImmovable; }
 
 void CodeStub::GenerateStubsAheadOfTime(Isolate* isolate) {
   CEntryStub::GenerateAheadOfTime(isolate);

src/mips64/code-stubs-mips64.h

@@ -19,7 +19,7 @@ class DirectCEntryStub : public PlatformCodeStub {
   void GenerateCall(MacroAssembler* masm, Register target);
 
  private:
-  bool NeedsImmovableCode() override { return true; }
+  Movability NeedsImmovableCode() override { return kImmovable; }
 
   DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
   DEFINE_PLATFORM_CODE_STUB(DirectCEntry, PlatformCodeStub);

src/ppc/code-stubs-ppc.cc

@@ -258,9 +258,7 @@ void MathPowStub::Generate(MacroAssembler* masm) {
   __ Ret();
 }
 
-
-bool CEntryStub::NeedsImmovableCode() { return true; }
-
+Movability CEntryStub::NeedsImmovableCode() { return kImmovable; }
 
 void CodeStub::GenerateStubsAheadOfTime(Isolate* isolate) {
   CEntryStub::GenerateAheadOfTime(isolate);

src/ppc/code-stubs-ppc.h

@@ -19,7 +19,7 @@ class DirectCEntryStub : public PlatformCodeStub {
   void GenerateCall(MacroAssembler* masm, Register target);
 
  private:
-  bool NeedsImmovableCode() override { return true; }
+  Movability NeedsImmovableCode() override { return kImmovable; }
 
   DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
   DEFINE_PLATFORM_CODE_STUB(DirectCEntry, PlatformCodeStub);

src/s390/code-stubs-s390.cc

@@ -249,7 +249,7 @@ void MathPowStub::Generate(MacroAssembler* masm) {
   __ Ret();
 }
 
-bool CEntryStub::NeedsImmovableCode() { return true; }
+Movability CEntryStub::NeedsImmovableCode() { return kImmovable; }
 
 void CodeStub::GenerateStubsAheadOfTime(Isolate* isolate) {
   CEntryStub::GenerateAheadOfTime(isolate);

src/s390/code-stubs-s390.h

@@ -19,7 +19,7 @@ class DirectCEntryStub : public PlatformCodeStub {
   void GenerateCall(MacroAssembler* masm, Register target);
 
  private:
-  bool NeedsImmovableCode() override { return true; }
+  Movability NeedsImmovableCode() override { return kImmovable; }
 
   DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
   DEFINE_PLATFORM_CODE_STUB(DirectCEntry, PlatformCodeStub);

src/x64/code-stubs-x64.cc

@@ -251,11 +251,7 @@ void MathPowStub::Generate(MacroAssembler* masm) {
   __ ret(0);
 }
 
-
-bool CEntryStub::NeedsImmovableCode() {
-  return false;
-}
-
+Movability CEntryStub::NeedsImmovableCode() { return kMovable; }
 
 void CodeStub::GenerateStubsAheadOfTime(Isolate* isolate) {
   CEntryStub::GenerateAheadOfTime(isolate);

test/cctest/heap/test-heap.cc

@@ -5801,7 +5801,6 @@ Handle<Code> GenerateDummyImmovableCode(Isolate* isolate) {
 
   CodeDesc desc;
   assm.GetCode(isolate, &desc);
-  const bool kImmovable = true;
   Handle<Code> code = isolate->factory()->NewCode(
       desc, Code::STUB, Handle<Code>(), HandlerTable::Empty(isolate),
       MaybeHandle<ByteArray>(), DeoptimizationData::Empty(isolate), kImmovable);