Rewrite class initialization check elimination.
Split the notion of type being in dex cache away from the
class being initialized. Include static invokes in the class
initialization elimination pass.
Change-Id: Ie3760d8fd55b987f9507f32ef51456a57d79e3fb
diff --git a/compiler/driver/compiler_driver-inl.h b/compiler/driver/compiler_driver-inl.h
index 3325568..1805d59 100644
--- a/compiler/driver/compiler_driver-inl.h
+++ b/compiler/driver/compiler_driver-inl.h
@@ -93,6 +93,10 @@
return field->IsVolatile();
}
+inline MemberOffset CompilerDriver::GetFieldOffset(mirror::ArtField* field) {
+ return field->GetOffset();
+}
+
inline std::pair<bool, bool> CompilerDriver::IsFastInstanceField(
mirror::DexCache* dex_cache, mirror::Class* referrer_class,
mirror::ArtField* resolved_field, uint16_t field_idx) {
@@ -107,16 +111,12 @@
inline std::pair<bool, bool> CompilerDriver::IsFastStaticField(
mirror::DexCache* dex_cache, mirror::Class* referrer_class,
- mirror::ArtField* resolved_field, uint16_t field_idx, MemberOffset* field_offset,
- uint32_t* storage_index, bool* is_referrers_class, bool* is_initialized) {
+ mirror::ArtField* resolved_field, uint16_t field_idx, uint32_t* storage_index) {
DCHECK(resolved_field->IsStatic());
if (LIKELY(referrer_class != nullptr)) {
mirror::Class* fields_class = resolved_field->GetDeclaringClass();
if (fields_class == referrer_class) {
- *field_offset = resolved_field->GetOffset();
*storage_index = fields_class->GetDexTypeIndex();
- *is_referrers_class = true; // implies no worrying about class initialization
- *is_initialized = true;
return std::make_pair(true, true);
}
if (referrer_class->CanAccessResolvedField(fields_class, resolved_field,
@@ -148,23 +148,30 @@
}
}
if (storage_idx != DexFile::kDexNoIndex) {
- *field_offset = resolved_field->GetOffset();
*storage_index = storage_idx;
- *is_referrers_class = false;
- *is_initialized = fields_class->IsInitialized() &&
- CanAssumeTypeIsPresentInDexCache(*dex_file, storage_idx);
return std::make_pair(true, !resolved_field->IsFinal());
}
}
}
// Conservative defaults.
- *field_offset = MemberOffset(0u);
*storage_index = DexFile::kDexNoIndex;
- *is_referrers_class = false;
- *is_initialized = false;
return std::make_pair(false, false);
}
+inline bool CompilerDriver::IsStaticFieldInReferrerClass(mirror::Class* referrer_class,
+ mirror::ArtField* resolved_field) {
+ DCHECK(resolved_field->IsStatic());
+ mirror::Class* fields_class = resolved_field->GetDeclaringClass();
+ return referrer_class == fields_class;
+}
+
+inline bool CompilerDriver::IsStaticFieldsClassInitialized(mirror::Class* referrer_class,
+ mirror::ArtField* resolved_field) {
+ DCHECK(resolved_field->IsStatic());
+ mirror::Class* fields_class = resolved_field->GetDeclaringClass();
+ return fields_class == referrer_class || fields_class->IsInitialized();
+}
+
inline mirror::ArtMethod* CompilerDriver::ResolveMethod(
ScopedObjectAccess& soa, Handle<mirror::DexCache> dex_cache,
Handle<mirror::ClassLoader> class_loader, const DexCompilationUnit* mUnit,
@@ -312,14 +319,13 @@
return stats_flags;
}
-inline bool CompilerDriver::NeedsClassInitialization(mirror::Class* referrer_class,
- mirror::ArtMethod* resolved_method) {
+inline bool CompilerDriver::IsMethodsClassInitialized(mirror::Class* referrer_class,
+ mirror::ArtMethod* resolved_method) {
if (!resolved_method->IsStatic()) {
- return false;
+ return true;
}
mirror::Class* methods_class = resolved_method->GetDeclaringClass();
- // NOTE: Unlike in IsFastStaticField(), we don't check CanAssumeTypeIsPresentInDexCache() here.
- return methods_class != referrer_class && !methods_class->IsInitialized();
+ return methods_class == referrer_class || methods_class->IsInitialized();
}
} // namespace art
diff --git a/compiler/driver/compiler_driver.cc b/compiler/driver/compiler_driver.cc
index a60c5bc..eb5739f 100644
--- a/compiler/driver/compiler_driver.cc
+++ b/compiler/driver/compiler_driver.cc
@@ -1094,11 +1094,17 @@
if (resolved_field != nullptr && referrer_class != nullptr) {
*is_volatile = IsFieldVolatile(resolved_field);
std::pair<bool, bool> fast_path = IsFastStaticField(
- dex_cache, referrer_class, resolved_field, field_idx, field_offset,
- storage_index, is_referrers_class, is_initialized);
+ dex_cache, referrer_class, resolved_field, field_idx, storage_index);
result = is_put ? fast_path.second : fast_path.first;
}
- if (!result) {
+ if (result) {
+ *field_offset = GetFieldOffset(resolved_field);
+ *is_referrers_class = IsStaticFieldInReferrerClass(referrer_class, resolved_field);
+ // *is_referrers_class == true implies no worrying about class initialization.
+ *is_initialized = (*is_referrers_class) ||
+ (IsStaticFieldsClassInitialized(referrer_class, resolved_field) &&
+ CanAssumeTypeIsPresentInDexCache(*mUnit->GetDexFile(), *storage_index));
+ } else {
// Conservative defaults.
*is_volatile = true;
*field_offset = MemberOffset(static_cast<size_t>(-1));
diff --git a/compiler/driver/compiler_driver.h b/compiler/driver/compiler_driver.h
index 0796f48..6764aef 100644
--- a/compiler/driver/compiler_driver.h
+++ b/compiler/driver/compiler_driver.h
@@ -233,6 +233,7 @@
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
bool IsFieldVolatile(mirror::ArtField* field) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+ MemberOffset GetFieldOffset(mirror::ArtField* field) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
// Can we fast-path an IGET/IPUT access to an instance field? If yes, compute the field offset.
std::pair<bool, bool> IsFastInstanceField(
@@ -240,13 +241,20 @@
mirror::ArtField* resolved_field, uint16_t field_idx)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
- // Can we fast-path an SGET/SPUT access to a static field? If yes, compute the field offset,
- // the type index of the declaring class in the referrer's dex file and whether the declaring
- // class is the referrer's class or at least can be assumed to be initialized.
+ // Can we fast-path an SGET/SPUT access to a static field? If yes, compute the type index
+ // of the declaring class in the referrer's dex file.
std::pair<bool, bool> IsFastStaticField(
mirror::DexCache* dex_cache, mirror::Class* referrer_class,
- mirror::ArtField* resolved_field, uint16_t field_idx, MemberOffset* field_offset,
- uint32_t* storage_index, bool* is_referrers_class, bool* is_initialized)
+ mirror::ArtField* resolved_field, uint16_t field_idx, uint32_t* storage_index)
+ SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+
+ // Is static field's in referrer's class?
+ bool IsStaticFieldInReferrerClass(mirror::Class* referrer_class, mirror::ArtField* resolved_field)
+ SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+
+ // Is static field's class initialized?
+ bool IsStaticFieldsClassInitialized(mirror::Class* referrer_class,
+ mirror::ArtField* resolved_field)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
// Resolve a method. Returns nullptr on failure, including incompatible class change.
@@ -277,8 +285,10 @@
uintptr_t* direct_code, uintptr_t* direct_method)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
- // Does invokation of the resolved method need class initialization?
- bool NeedsClassInitialization(mirror::Class* referrer_class, mirror::ArtMethod* resolved_method)
+ // Is method's class initialized for an invoke?
+ // For static invokes to determine whether we need to consider potential call to <clinit>().
+ // For non-static invokes, assuming a non-null reference, the class is always initialized.
+ bool IsMethodsClassInitialized(mirror::Class* referrer_class, mirror::ArtMethod* resolved_method)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
void ProcessedInstanceField(bool resolved);