diff options
Diffstat (limited to 'compiler/optimizing/code_generator_arm.cc')
| -rw-r--r-- | compiler/optimizing/code_generator_arm.cc | 164 |
1 files changed, 126 insertions, 38 deletions
diff --git a/compiler/optimizing/code_generator_arm.cc b/compiler/optimizing/code_generator_arm.cc index 18f2ff3e30..d709e861e1 100644 --- a/compiler/optimizing/code_generator_arm.cc +++ b/compiler/optimizing/code_generator_arm.cc @@ -6033,12 +6033,26 @@ void InstructionCodeGeneratorARM::VisitThrow(HThrow* instruction) { CheckEntrypointTypes<kQuickDeliverException, void, mirror::Object*>(); } -static bool TypeCheckNeedsATemporary(TypeCheckKind type_check_kind) { - return kEmitCompilerReadBarrier && - (kUseBakerReadBarrier || - type_check_kind == TypeCheckKind::kAbstractClassCheck || - type_check_kind == TypeCheckKind::kClassHierarchyCheck || - type_check_kind == TypeCheckKind::kArrayObjectCheck); +// Temp is used for read barrier. +static size_t NumberOfInstanceOfTemps(TypeCheckKind type_check_kind) { + if (kEmitCompilerReadBarrier && + (kUseBakerReadBarrier || + type_check_kind == TypeCheckKind::kAbstractClassCheck || + type_check_kind == TypeCheckKind::kClassHierarchyCheck || + type_check_kind == TypeCheckKind::kArrayObjectCheck)) { + return 1; + } + return 0; +} + +// InteraceCheck has 3 temps, one for holding the number of interfaces, one for the current +// interface pointer, one for loading the current interface. +// The other checks have one temp for loading the object's class. +static size_t NumberOfCheckCastTemps(TypeCheckKind type_check_kind) { + if (type_check_kind == TypeCheckKind::kInterfaceCheck) { + return 3; + } + return 1 + NumberOfInstanceOfTemps(type_check_kind); } void LocationsBuilderARM::VisitInstanceOf(HInstanceOf* instruction) { @@ -6070,11 +6084,7 @@ void LocationsBuilderARM::VisitInstanceOf(HInstanceOf* instruction) { // The "out" register is used as a temporary, so it overlaps with the inputs. // Note that TypeCheckSlowPathARM uses this register too. locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap); - // When read barriers are enabled, we need a temporary register for - // some cases. - if (TypeCheckNeedsATemporary(type_check_kind)) { - locations->AddTemp(Location::RequiresRegister()); - } + locations->AddRegisterTemps(NumberOfInstanceOfTemps(type_check_kind)); } void InstructionCodeGeneratorARM::VisitInstanceOf(HInstanceOf* instruction) { @@ -6085,9 +6095,9 @@ void InstructionCodeGeneratorARM::VisitInstanceOf(HInstanceOf* instruction) { Register cls = locations->InAt(1).AsRegister<Register>(); Location out_loc = locations->Out(); Register out = out_loc.AsRegister<Register>(); - Location maybe_temp_loc = TypeCheckNeedsATemporary(type_check_kind) ? - locations->GetTemp(0) : - Location::NoLocation(); + const size_t num_temps = NumberOfInstanceOfTemps(type_check_kind); + DCHECK_LE(num_temps, 1u); + Location maybe_temp_loc = (num_temps >= 1) ? locations->GetTemp(0) : Location::NoLocation(); uint32_t class_offset = mirror::Object::ClassOffset().Int32Value(); uint32_t super_offset = mirror::Class::SuperClassOffset().Int32Value(); uint32_t component_offset = mirror::Class::ComponentTypeOffset().Int32Value(); @@ -6102,7 +6112,12 @@ void InstructionCodeGeneratorARM::VisitInstanceOf(HInstanceOf* instruction) { } // /* HeapReference<Class> */ out = obj->klass_ - GenerateReferenceLoadTwoRegisters(instruction, out_loc, obj_loc, class_offset, maybe_temp_loc); + GenerateReferenceLoadTwoRegisters(instruction, + out_loc, + obj_loc, + class_offset, + maybe_temp_loc, + kEmitCompilerReadBarrier); switch (type_check_kind) { case TypeCheckKind::kExactCheck: { @@ -6254,13 +6269,7 @@ void LocationsBuilderARM::VisitCheckCast(HCheckCast* instruction) { LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(instruction, call_kind); locations->SetInAt(0, Location::RequiresRegister()); locations->SetInAt(1, Location::RequiresRegister()); - // Note that TypeCheckSlowPathARM uses this "temp" register too. - locations->AddTemp(Location::RequiresRegister()); - // When read barriers are enabled, we need an additional temporary - // register for some cases. - if (TypeCheckNeedsATemporary(type_check_kind)) { - locations->AddTemp(Location::RequiresRegister()); - } + locations->AddRegisterTemps(NumberOfCheckCastTemps(type_check_kind)); } void InstructionCodeGeneratorARM::VisitCheckCast(HCheckCast* instruction) { @@ -6271,13 +6280,18 @@ void InstructionCodeGeneratorARM::VisitCheckCast(HCheckCast* instruction) { Register cls = locations->InAt(1).AsRegister<Register>(); Location temp_loc = locations->GetTemp(0); Register temp = temp_loc.AsRegister<Register>(); - Location maybe_temp2_loc = TypeCheckNeedsATemporary(type_check_kind) ? - locations->GetTemp(1) : - Location::NoLocation(); - uint32_t class_offset = mirror::Object::ClassOffset().Int32Value(); - uint32_t super_offset = mirror::Class::SuperClassOffset().Int32Value(); - uint32_t component_offset = mirror::Class::ComponentTypeOffset().Int32Value(); - uint32_t primitive_offset = mirror::Class::PrimitiveTypeOffset().Int32Value(); + const size_t num_temps = NumberOfCheckCastTemps(type_check_kind); + DCHECK_LE(num_temps, 3u); + Location maybe_temp2_loc = (num_temps >= 2) ? locations->GetTemp(1) : Location::NoLocation(); + Location maybe_temp3_loc = (num_temps >= 3) ? locations->GetTemp(2) : Location::NoLocation(); + const uint32_t class_offset = mirror::Object::ClassOffset().Int32Value(); + const uint32_t super_offset = mirror::Class::SuperClassOffset().Int32Value(); + const uint32_t component_offset = mirror::Class::ComponentTypeOffset().Int32Value(); + const uint32_t primitive_offset = mirror::Class::PrimitiveTypeOffset().Int32Value(); + const uint32_t iftable_offset = mirror::Class::IfTableOffset().Uint32Value(); + const uint32_t array_length_offset = mirror::Array::LengthOffset().Uint32Value(); + const uint32_t object_array_data_offset = + mirror::Array::DataOffset(kHeapReferenceSize).Uint32Value(); bool is_type_check_slow_path_fatal = (type_check_kind == TypeCheckKind::kExactCheck || @@ -6296,12 +6310,17 @@ void InstructionCodeGeneratorARM::VisitCheckCast(HCheckCast* instruction) { __ CompareAndBranchIfZero(obj, &done); } - // /* HeapReference<Class> */ temp = obj->klass_ - GenerateReferenceLoadTwoRegisters(instruction, temp_loc, obj_loc, class_offset, maybe_temp2_loc); - switch (type_check_kind) { case TypeCheckKind::kExactCheck: case TypeCheckKind::kArrayCheck: { + // /* HeapReference<Class> */ temp = obj->klass_ + GenerateReferenceLoadTwoRegisters(instruction, + temp_loc, + obj_loc, + class_offset, + maybe_temp2_loc, + kEmitCompilerReadBarrier); + __ cmp(temp, ShifterOperand(cls)); // Jump to slow path for throwing the exception or doing a // more involved array check. @@ -6310,6 +6329,14 @@ void InstructionCodeGeneratorARM::VisitCheckCast(HCheckCast* instruction) { } case TypeCheckKind::kAbstractClassCheck: { + // /* HeapReference<Class> */ temp = obj->klass_ + GenerateReferenceLoadTwoRegisters(instruction, + temp_loc, + obj_loc, + class_offset, + maybe_temp2_loc, + kEmitCompilerReadBarrier); + // If the class is abstract, we eagerly fetch the super class of the // object to avoid doing a comparison we know will fail. Label loop; @@ -6328,6 +6355,14 @@ void InstructionCodeGeneratorARM::VisitCheckCast(HCheckCast* instruction) { } case TypeCheckKind::kClassHierarchyCheck: { + // /* HeapReference<Class> */ temp = obj->klass_ + GenerateReferenceLoadTwoRegisters(instruction, + temp_loc, + obj_loc, + class_offset, + maybe_temp2_loc, + kEmitCompilerReadBarrier); + // Walk over the class hierarchy to find a match. Label loop; __ Bind(&loop); @@ -6346,6 +6381,14 @@ void InstructionCodeGeneratorARM::VisitCheckCast(HCheckCast* instruction) { } case TypeCheckKind::kArrayObjectCheck: { + // /* HeapReference<Class> */ temp = obj->klass_ + GenerateReferenceLoadTwoRegisters(instruction, + temp_loc, + obj_loc, + class_offset, + maybe_temp2_loc, + kEmitCompilerReadBarrier); + // Do an exact check. __ cmp(temp, ShifterOperand(cls)); __ b(&done, EQ); @@ -6364,10 +6407,7 @@ void InstructionCodeGeneratorARM::VisitCheckCast(HCheckCast* instruction) { } case TypeCheckKind::kUnresolvedCheck: - case TypeCheckKind::kInterfaceCheck: - // We always go into the type check slow path for the unresolved - // and interface check cases. - // + // We always go into the type check slow path for the unresolved check case. // We cannot directly call the CheckCast runtime entry point // without resorting to a type checking slow path here (i.e. by // calling InvokeRuntime directly), as it would require to @@ -6375,8 +6415,54 @@ void InstructionCodeGeneratorARM::VisitCheckCast(HCheckCast* instruction) { // instruction (following the runtime calling convention), which // might be cluttered by the potential first read barrier // emission at the beginning of this method. + __ b(type_check_slow_path->GetEntryLabel()); break; + + case TypeCheckKind::kInterfaceCheck: { + // Avoid read barriers to improve performance of the fast path. We can not get false + // positives by doing this. + // /* HeapReference<Class> */ temp = obj->klass_ + GenerateReferenceLoadTwoRegisters(instruction, + temp_loc, + obj_loc, + class_offset, + maybe_temp2_loc, + /*emit_read_barrier*/ false); + + // /* HeapReference<Class> */ temp = temp->iftable_ + GenerateReferenceLoadTwoRegisters(instruction, + temp_loc, + temp_loc, + iftable_offset, + maybe_temp2_loc, + /*emit_read_barrier*/ false); + Label is_null; + // Null iftable means it is empty and will always fail the check. + // Not cbz since the temp may not be a low register. + __ CompareAndBranchIfZero(temp, &is_null); + + // Loop through the iftable and check if any class matches. + __ ldr(maybe_temp2_loc.AsRegister<Register>(), Address(temp, array_length_offset)); + + Label start_loop; + __ Bind(&start_loop); + __ ldr(maybe_temp3_loc.AsRegister<Register>(), Address(temp, object_array_data_offset)); + __ MaybeUnpoisonHeapReference(maybe_temp3_loc.AsRegister<Register>()); + __ cmp(cls, ShifterOperand(maybe_temp3_loc.AsRegister<Register>())); + __ b(&done, EQ); // Return if same class. + // Go to next interface. + __ add(temp, temp, ShifterOperand(2 * kHeapReferenceSize)); + __ sub(maybe_temp2_loc.AsRegister<Register>(), + maybe_temp2_loc.AsRegister<Register>(), + ShifterOperand(2)); + // Not cbnz since the temp may not be a low register. + __ CompareAndBranchIfNonZero(maybe_temp2_loc.AsRegister<Register>(), &start_loop); + __ Bind(&is_null); + + __ b(type_check_slow_path->GetEntryLabel()); + break; + } } __ Bind(&done); @@ -6684,10 +6770,12 @@ void InstructionCodeGeneratorARM::GenerateReferenceLoadTwoRegisters(HInstruction Location out, Location obj, uint32_t offset, - Location maybe_temp) { + Location maybe_temp, + bool emit_read_barrier) { Register out_reg = out.AsRegister<Register>(); Register obj_reg = obj.AsRegister<Register>(); - if (kEmitCompilerReadBarrier) { + if (emit_read_barrier) { + DCHECK(kEmitCompilerReadBarrier); if (kUseBakerReadBarrier) { DCHECK(maybe_temp.IsRegister()) << maybe_temp; // Load with fast path based Baker's read barrier. |