optimizing: Build HConstructorFence for HNewArray/HNewInstance nodes
Also fixes:
* LSE, code_sinking to keep optimizing new-instance if it did so before
* Various tests to expect constructor fences after new-instance
Sidenote: new-instance String does not get a ConstructorFence; the
special StringFactory calls are assumed to be self-fencing.
Metric changes on go/lem:
* CodeSize -0.262% in ART-Compile (ARMv8)
* RunTime -0.747% for all (linux-armv8)
(No changes expected to x86, constructor fences are no-op).
The RunTime regression is temporary until art_quick_alloc_* entrypoints have their
DMBs removed in a follow up CL.
Test: art/test.py
Bug: 36656456
Change-Id: I6a936a6e51c623e1c6b5b22eee5c3c72bebbed35
diff --git a/compiler/optimizing/instruction_builder.h b/compiler/optimizing/instruction_builder.h
index 2fb5c7b..e968760 100644
--- a/compiler/optimizing/instruction_builder.h
+++ b/compiler/optimizing/instruction_builder.h
@@ -194,12 +194,12 @@
uint32_t register_index);
// Builds a new array node and the instructions that fill it.
- void BuildFilledNewArray(uint32_t dex_pc,
- dex::TypeIndex type_index,
- uint32_t number_of_vreg_arguments,
- bool is_range,
- uint32_t* args,
- uint32_t register_index);
+ HNewArray* BuildFilledNewArray(uint32_t dex_pc,
+ dex::TypeIndex type_index,
+ uint32_t number_of_vreg_arguments,
+ bool is_range,
+ uint32_t* args,
+ uint32_t register_index);
void BuildFillArrayData(const Instruction& instruction, uint32_t dex_pc);
@@ -288,7 +288,11 @@
REQUIRES_SHARED(Locks::mutator_lock_);
// Build a HNewInstance instruction.
- bool BuildNewInstance(dex::TypeIndex type_index, uint32_t dex_pc);
+ HNewInstance* BuildNewInstance(dex::TypeIndex type_index, uint32_t dex_pc);
+
+ // Build a HConstructorFence for HNewInstance and HNewArray instructions. This ensures the
+ // happens-before ordering for default-initialization of the object referred to by new_instance.
+ void BuildConstructorFenceForAllocation(HInstruction* allocation);
// Return whether the compiler can assume `cls` is initialized.
bool IsInitialized(Handle<mirror::Class> cls) const