Pass JIT roots as a vector<Handle<>> to JIT cache.
This avoids creating an object on the heap and thus
prevents issues for the 904-object-allocation in the
JIT-at-first-use configuration.
Test: run_build_test_target.py -j48 art-jit-on-first-use
(test 904 passes; test 1935 still failing).
Bug: 116189667
Change-Id: I58c0c8cb2d78edc63dab7d72e69b882abbfb79fd
diff --git a/compiler/optimizing/code_generator.cc b/compiler/optimizing/code_generator.cc
index e84896b..d440cf3 100644
--- a/compiler/optimizing/code_generator.cc
+++ b/compiler/optimizing/code_generator.cc
@@ -197,7 +197,7 @@
return GetNumberOfJitStringRoots() + GetNumberOfJitClassRoots();
}
- void EmitJitRoots(Handle<mirror::ObjectArray<mirror::Object>> roots)
+ void EmitJitRoots(/*out*/std::vector<Handle<mirror::Object>>* roots)
REQUIRES_SHARED(Locks::mutator_lock_);
private:
@@ -230,29 +230,31 @@
};
void CodeGenerator::CodeGenerationData::EmitJitRoots(
- Handle<mirror::ObjectArray<mirror::Object>> roots) {
- DCHECK_EQ(static_cast<size_t>(roots->GetLength()), GetNumberOfJitRoots());
+ /*out*/std::vector<Handle<mirror::Object>>* roots) {
+ DCHECK(roots->empty());
+ roots->reserve(GetNumberOfJitRoots());
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
size_t index = 0;
for (auto& entry : jit_string_roots_) {
// Update the `roots` with the string, and replace the address temporarily
// stored to the index in the table.
uint64_t address = entry.second;
- roots->Set(index, reinterpret_cast<StackReference<mirror::String>*>(address)->AsMirrorPtr());
- DCHECK(roots->Get(index) != nullptr);
+ roots->emplace_back(reinterpret_cast<StackReference<mirror::Object>*>(address));
+ DCHECK(roots->back() != nullptr);
+ DCHECK(roots->back()->IsString());
entry.second = index;
// Ensure the string is strongly interned. This is a requirement on how the JIT
// handles strings. b/32995596
- class_linker->GetInternTable()->InternStrong(
- reinterpret_cast<mirror::String*>(roots->Get(index)));
+ class_linker->GetInternTable()->InternStrong(roots->back()->AsString());
++index;
}
for (auto& entry : jit_class_roots_) {
// Update the `roots` with the class, and replace the address temporarily
// stored to the index in the table.
uint64_t address = entry.second;
- roots->Set(index, reinterpret_cast<StackReference<mirror::Class>*>(address)->AsMirrorPtr());
- DCHECK(roots->Get(index) != nullptr);
+ roots->emplace_back(reinterpret_cast<StackReference<mirror::Object>*>(address));
+ DCHECK(roots->back() != nullptr);
+ DCHECK(roots->back()->IsClass());
entry.second = index;
++index;
}
@@ -1645,8 +1647,8 @@
}
void CodeGenerator::EmitJitRoots(uint8_t* code,
- Handle<mirror::ObjectArray<mirror::Object>> roots,
- const uint8_t* roots_data) {
+ const uint8_t* roots_data,
+ /*out*/std::vector<Handle<mirror::Object>>* roots) {
code_generation_data_->EmitJitRoots(roots);
EmitJitRootPatches(code, roots_data);
}
diff --git a/compiler/optimizing/code_generator.h b/compiler/optimizing/code_generator.h
index 2ca15f7..4e73e0b 100644
--- a/compiler/optimizing/code_generator.h
+++ b/compiler/optimizing/code_generator.h
@@ -356,8 +356,8 @@
// Fills the `literals` array with literals collected during code generation.
// Also emits literal patches.
void EmitJitRoots(uint8_t* code,
- Handle<mirror::ObjectArray<mirror::Object>> roots,
- const uint8_t* roots_data)
+ const uint8_t* roots_data,
+ /*out*/std::vector<Handle<mirror::Object>>* roots)
REQUIRES_SHARED(Locks::mutator_lock_);
bool IsLeafMethod() const {
diff --git a/compiler/optimizing/optimizing_compiler.cc b/compiler/optimizing/optimizing_compiler.cc
index 5f6f71d..9ae025b 100644
--- a/compiler/optimizing/optimizing_compiler.cc
+++ b/compiler/optimizing/optimizing_compiler.cc
@@ -1218,7 +1218,7 @@
const CompilerOptions& compiler_options = GetCompilerDriver()->GetCompilerOptions();
JniCompiledMethod jni_compiled_method = ArtQuickJniCompileMethod(
compiler_options, access_flags, method_idx, *dex_file);
- ScopedNullHandle<mirror::ObjectArray<mirror::Object>> roots;
+ std::vector<Handle<mirror::Object>> roots;
ArenaSet<ArtMethod*, std::less<ArtMethod*>> cha_single_implementation_list(
allocator.Adapter(kArenaAllocCHA));
ArenaStack arena_stack(runtime->GetJitArenaPool());
@@ -1320,19 +1320,6 @@
ScopedArenaVector<uint8_t> stack_map = codegen->BuildStackMaps(code_item);
size_t number_of_roots = codegen->GetNumberOfJitRoots();
- // We allocate an object array to ensure the JIT roots that we will collect in EmitJitRoots
- // will be visible by the GC between EmitLiterals and CommitCode. Once CommitCode is
- // executed, this array is not needed.
- Handle<mirror::ObjectArray<mirror::Object>> roots(
- hs.NewHandle(mirror::ObjectArray<mirror::Object>::Alloc(
- self, GetClassRoot<mirror::ObjectArray<mirror::Object>>(), number_of_roots)));
- if (roots == nullptr) {
- // Out of memory, just clear the exception to avoid any Java exception uncaught problems.
- MaybeRecordStat(compilation_stats_.get(), MethodCompilationStat::kJitOutOfMemoryForCommit);
- DCHECK(self->IsExceptionPending());
- self->ClearException();
- return false;
- }
uint8_t* stack_map_data = nullptr;
uint8_t* roots_data = nullptr;
uint32_t data_size = code_cache->ReserveData(self,
@@ -1346,7 +1333,14 @@
return false;
}
memcpy(stack_map_data, stack_map.data(), stack_map.size());
- codegen->EmitJitRoots(code_allocator.GetData(), roots, roots_data);
+ std::vector<Handle<mirror::Object>> roots;
+ codegen->EmitJitRoots(code_allocator.GetData(), roots_data, &roots);
+ // The root Handle<>s filled by the codegen reference entries in the VariableSizedHandleScope.
+ DCHECK(std::all_of(roots.begin(),
+ roots.end(),
+ [&handles](Handle<mirror::Object> root){
+ return handles.Contains(root.GetReference());
+ }));
const void* code = code_cache->CommitCode(
self,