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dart / sdk.git / bb53879638ff8f2e8dfac561d588700fb6513db0 / . / runtime / vm / compiler / stub_code_compiler_arm.cc
blob: 4d83975c794543ef716f8777e69c17070adf4375 [file] [log] [blame]
// Copyright (c) 2019, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "vm/compiler/runtime_api.h"
#include "vm/globals.h"
// For `AllocateObjectInstr::WillAllocateNewOrRemembered`
// For `GenericCheckBoundInstr::UseUnboxedRepresentation`
#include "vm/compiler/backend/il.h"
#define SHOULD_NOT_INCLUDE_RUNTIME
#include "vm/compiler/stub_code_compiler.h"
#if defined(TARGET_ARCH_ARM)
#include "vm/class_id.h"
#include "vm/code_entry_kind.h"
#include "vm/compiler/api/type_check_mode.h"
#include "vm/compiler/assembler/assembler.h"
#include "vm/compiler/backend/locations.h"
#include "vm/constants.h"
#include "vm/ffi_callback_metadata.h"
#include "vm/instructions.h"
#include "vm/static_type_exactness_state.h"
#include "vm/tags.h"
#define __ assembler->
namespace dart {
namespace compiler {
// Ensures that [R0] is a new object, if not it will be added to the remembered
// set via a leaf runtime call.
//
// WARNING: This might clobber all registers except for [R0], [THR] and [FP].
// The caller should simply call LeaveStubFrame() and return.
void StubCodeCompiler::EnsureIsNewOrRemembered() {
// If the object is not in an active TLAB, we call a leaf-runtime to add it to
// the remembered set and/or deferred marking worklist. This test assumes a
// Page's TLAB use is always ascending.
Label done;
__ AndImmediate(TMP, R0, target::kPageMask);
__ LoadFromOffset(TMP, TMP, target::Page::original_top_offset());
__ CompareRegisters(R0, TMP);
__ BranchIf(UNSIGNED_GREATER_EQUAL, &done);
{
LeafRuntimeScope rt(assembler,
/*frame_size=*/0,
/*preserve_registers=*/false);
// [R0] already contains first argument.
__ mov(R1, Operand(THR));
rt.Call(kEnsureRememberedAndMarkingDeferredRuntimeEntry, 2);
}
__ Bind(&done);
}
// Input parameters:
// LR : return address.
// SP : address of last argument in argument array.
// SP + 4*R4 - 4 : address of first argument in argument array.
// SP + 4*R4 : address of return value.
// R9 : address of the runtime function to call.
// R4 : number of arguments to the call.
void StubCodeCompiler::GenerateCallToRuntimeStub() {
const intptr_t thread_offset = target::NativeArguments::thread_offset();
const intptr_t argc_tag_offset = target::NativeArguments::argc_tag_offset();
const intptr_t argv_offset = target::NativeArguments::argv_offset();
const intptr_t retval_offset = target::NativeArguments::retval_offset();
__ ldr(CODE_REG, Address(THR, target::Thread::call_to_runtime_stub_offset()));
__ EnterStubFrame();
// Save exit frame information to enable stack walking as we are about
// to transition to Dart VM C++ code.
__ StoreToOffset(FP, THR, target::Thread::top_exit_frame_info_offset());
// Mark that the thread exited generated code through a runtime call.
__ LoadImmediate(R8, target::Thread::exit_through_runtime_call());
__ StoreToOffset(R8, THR, target::Thread::exit_through_ffi_offset());
#if defined(DEBUG)
{
Label ok;
// Check that we are always entering from Dart code.
__ LoadFromOffset(R8, THR, target::Thread::vm_tag_offset());
__ CompareImmediate(R8, VMTag::kDartTagId);
__ b(&ok, EQ);
__ Stop("Not coming from Dart code.");
__ Bind(&ok);
}
#endif
// Mark that the thread is executing VM code.
__ StoreToOffset(R9, THR, target::Thread::vm_tag_offset());
// Reserve space for arguments and align frame before entering C++ world.
// target::NativeArguments are passed in registers.
ASSERT(target::NativeArguments::StructSize() == 4 * target::kWordSize);
__ ReserveAlignedFrameSpace(0);
// Pass target::NativeArguments structure by value and call runtime.
// Registers R0, R1, R2, and R3 are used.
ASSERT(thread_offset == 0 * target::kWordSize);
// Set thread in NativeArgs.
__ mov(R0, Operand(THR));
ASSERT(argc_tag_offset == 1 * target::kWordSize);
__ mov(R1, Operand(R4)); // Set argc in target::NativeArguments.
ASSERT(argv_offset == 2 * target::kWordSize);
__ add(R2, FP, Operand(R4, LSL, 2)); // Compute argv.
// Set argv in target::NativeArguments.
__ AddImmediate(R2,
target::frame_layout.param_end_from_fp * target::kWordSize);
ASSERT(retval_offset == 3 * target::kWordSize);
__ add(R3, R2,
Operand(target::kWordSize)); // Retval is next to 1st argument.
// Call runtime or redirection via simulator.
__ blx(R9);
// Mark that the thread is executing Dart code.
__ LoadImmediate(R2, VMTag::kDartTagId);
__ StoreToOffset(R2, THR, target::Thread::vm_tag_offset());
// Mark that the thread has not exited generated Dart code.
__ LoadImmediate(R2, 0);
__ StoreToOffset(R2, THR, target::Thread::exit_through_ffi_offset());
// Reset exit frame information in Isolate's mutator thread structure.
__ StoreToOffset(R2, THR, target::Thread::top_exit_frame_info_offset());
// Restore the global object pool after returning from runtime (old space is
// moving, so the GOP could have been relocated).
if (FLAG_precompiled_mode) {
__ SetupGlobalPoolAndDispatchTable();
}
__ LeaveStubFrame();
// The following return can jump to a lazy-deopt stub, which assumes R0
// contains a return value and will save it in a GC-visible way. We therefore
// have to ensure R0 does not contain any garbage value left from the C
// function we called (which has return type "void").
// (See GenerateDeoptimizationSequence::saved_result_slot_from_fp.)
__ LoadImmediate(R0, 0);
__ Ret();
}
void StubCodeCompiler::GenerateSharedStubGeneric(
bool save_fpu_registers,
intptr_t self_code_stub_offset_from_thread,
bool allow_return,
std::function<void()> perform_runtime_call) {
// We want the saved registers to appear like part of the caller's frame, so
// we push them before calling EnterStubFrame.
RegisterSet all_registers;
all_registers.AddAllNonReservedRegisters(save_fpu_registers);
// To make the stack map calculation architecture independent we do the same
// as on intel.
READS_RETURN_ADDRESS_FROM_LR(__ Push(LR));
__ PushRegisters(all_registers);
__ ldr(CODE_REG, Address(THR, self_code_stub_offset_from_thread));
__ EnterStubFrame();
perform_runtime_call();
if (!allow_return) {
__ Breakpoint();
return;
}
__ LeaveStubFrame();
__ PopRegisters(all_registers);
__ Drop(1); // We use the LR restored via LeaveStubFrame.
READS_RETURN_ADDRESS_FROM_LR(__ bx(LR));
}
void StubCodeCompiler::GenerateSharedStub(
bool save_fpu_registers,
const RuntimeEntry* target,
intptr_t self_code_stub_offset_from_thread,
bool allow_return,
bool store_runtime_result_in_result_register) {
ASSERT(!store_runtime_result_in_result_register || allow_return);
auto perform_runtime_call = [&]() {
if (store_runtime_result_in_result_register) {
// Reserve space for the result on the stack. This needs to be a GC
// safe value.
__ PushImmediate(Smi::RawValue(0));
}
__ CallRuntime(*target, /*argument_count=*/0);
if (store_runtime_result_in_result_register) {
__ PopRegister(R0);
__ str(R0,
Address(FP, target::kWordSize *
StubCodeCompiler::WordOffsetFromFpToCpuRegister(
SharedSlowPathStubABI::kResultReg)));
}
};
GenerateSharedStubGeneric(save_fpu_registers,
self_code_stub_offset_from_thread, allow_return,
perform_runtime_call);
}
void StubCodeCompiler::GenerateEnterSafepointStub() {
RegisterSet all_registers;
all_registers.AddAllGeneralRegisters();
__ PushRegisters(all_registers);
SPILLS_LR_TO_FRAME(__ EnterFrame((1 << FP) | (1 << LR), 0));
__ ReserveAlignedFrameSpace(0);
__ ldr(R0, Address(THR, kEnterSafepointRuntimeEntry.OffsetFromThread()));
__ blx(R0);
RESTORES_LR_FROM_FRAME(__ LeaveFrame((1 << FP) | (1 << LR), 0));
__ PopRegisters(all_registers);
__ Ret();
}
static void GenerateExitSafepointStubCommon(Assembler* assembler,
uword runtime_entry_offset) {
RegisterSet all_registers;
all_registers.AddAllGeneralRegisters();
__ PushRegisters(all_registers);
SPILLS_LR_TO_FRAME(__ EnterFrame((1 << FP) | (1 << LR), 0));
__ ReserveAlignedFrameSpace(0);
__ VerifyNotInGenerated(R0);
// Set the execution state to VM while waiting for the safepoint to end.
// This isn't strictly necessary but enables tests to check that we're not
// in native code anymore. See tests/ffi/function_gc_test.dart for example.
__ LoadImmediate(R0, target::Thread::vm_execution_state());
__ str(R0, Address(THR, target::Thread::execution_state_offset()));
__ ldr(R0, Address(THR, runtime_entry_offset));
__ blx(R0);
RESTORES_LR_FROM_FRAME(__ LeaveFrame((1 << FP) | (1 << LR), 0));
__ PopRegisters(all_registers);
__ Ret();
}
void StubCodeCompiler::GenerateExitSafepointStub() {
GenerateExitSafepointStubCommon(
assembler, kExitSafepointRuntimeEntry.OffsetFromThread());
}
void StubCodeCompiler::GenerateExitSafepointIgnoreUnwindInProgressStub() {
GenerateExitSafepointStubCommon(
assembler,
kExitSafepointIgnoreUnwindInProgressRuntimeEntry.OffsetFromThread());
}
// Call a native function within a safepoint.
//
// On entry:
// Stack: set up for call, incl. alignment
// R8: target to call
//
// On exit:
// Stack: preserved
// NOTFP, R4: clobbered, although normally callee-saved
void StubCodeCompiler::GenerateCallNativeThroughSafepointStub() {
COMPILE_ASSERT(IsAbiPreservedRegister(R4));
// TransitionGeneratedToNative might clobber LR if it takes the slow path.
SPILLS_RETURN_ADDRESS_FROM_LR_TO_REGISTER(__ mov(R4, Operand(LR)));
__ LoadImmediate(R9, target::Thread::exit_through_ffi());
__ TransitionGeneratedToNative(R8, FPREG, R9 /*volatile*/, NOTFP,
/*enter_safepoint=*/true);
__ blx(R8);
__ TransitionNativeToGenerated(R9 /*volatile*/, NOTFP,
/*exit_safepoint=*/true);
__ bx(R4);
}
void StubCodeCompiler::GenerateLoadBSSEntry(BSS::Relocation relocation,
Register dst,
Register tmp) {
compiler::Label skip_reloc;
__ b(&skip_reloc);
InsertBSSRelocation(relocation);
__ Bind(&skip_reloc);
// For historical reasons, the PC on ARM points 8 bytes (two instructions)
// past the current instruction.
__ sub(tmp, PC,
compiler::Operand(Instr::kPCReadOffset + compiler::target::kWordSize));
// tmp holds the address of the relocation.
__ ldr(dst, compiler::Address(tmp));
// dst holds the relocation itself: tmp - bss_start.
// tmp = tmp + (bss_start - tmp) = bss_start
__ add(tmp, tmp, compiler::Operand(dst));
// tmp holds the start of the BSS section.
// Load the "get-thread" routine: *bss_start.
__ ldr(dst, compiler::Address(tmp));
}
void StubCodeCompiler::GenerateLoadFfiCallbackMetadataRuntimeFunction(
uword function_index,
Register dst) {
// Keep in sync with FfiCallbackMetadata::EnsureFirstTrampolinePageLocked.
// Note: If the stub was aligned, this could be a single PC relative load.
// Load a pointer to the beginning of the stub into dst.
const intptr_t code_size = __ CodeSize();
__ SubImmediate(dst, PC, Instr::kPCReadOffset + code_size);
// Round dst down to the page size.
__ AndImmediate(dst, dst, FfiCallbackMetadata::kPageMask);
// Load the function from the function table.
__ LoadFromOffset(dst, dst,
FfiCallbackMetadata::RuntimeFunctionOffset(function_index));
}
void StubCodeCompiler::GenerateFfiCallbackTrampolineStub() {
#if defined(USING_SIMULATOR) && !defined(DART_PRECOMPILER)
// TODO(37299): FFI is not supported in SIMARM.
__ Breakpoint();
#else
Label body;
// TMP is volatile and not used for passing any arguments.
COMPILE_ASSERT(!IsCalleeSavedRegister(TMP) && !IsArgumentRegister(TMP));
for (intptr_t i = 0; i < FfiCallbackMetadata::NumCallbackTrampolinesPerPage();
++i) {
// The FfiCallbackMetadata table is keyed by the trampoline entry point. So
// look up the current PC, then jump to the shared section. The PC is offset
// by Instr::kPCReadOffset, which is subtracted below.
__ mov(TMP, Operand(PC));
__ b(&body);
}
ASSERT(__ CodeSize() ==
FfiCallbackMetadata::kNativeCallbackTrampolineSize *
FfiCallbackMetadata::NumCallbackTrampolinesPerPage());
__ Bind(&body);
const intptr_t shared_stub_start = __ CodeSize();
// Save THR (callee-saved), R4 & R5 (temporaries, callee-saved), and LR.
COMPILE_ASSERT(FfiCallbackMetadata::kNativeCallbackTrampolineStackDelta == 4);
SPILLS_LR_TO_FRAME(
__ PushList((1 << LR) | (1 << THR) | (1 << R4) | (1 << R5)));
// The PC is in TMP, but is offset by kPCReadOffset. To get the actual
// trampoline entry point we need to subtract that.
__ sub(R4, TMP, Operand(Instr::kPCReadOffset));
COMPILE_ASSERT(IsCalleeSavedRegister(R4));
COMPILE_ASSERT(!IsArgumentRegister(THR));
RegisterSet argument_registers;
argument_registers.AddAllArgumentRegisters();
__ PushRegisters(argument_registers);
// Load the thread, verify the callback ID and exit the safepoint.
//
// We exit the safepoint inside DLRT_GetFfiCallbackMetadata in order to save
// code size on this shared stub.
{
__ mov(R0, Operand(R4));
// We also need to look up the entry point for the trampoline. This is
// returned using a pointer passed to the second arg of the C function
// below. We aim that pointer at a reserved stack slot.
__ sub(SP, SP, Operand(compiler::target::kWordSize));
__ mov(R1, Operand(SP));
// We also need to know if this is a sync or async callback. This is also
// returned by pointer.
__ sub(SP, SP, Operand(compiler::target::kWordSize));
__ mov(R2, Operand(SP));
__ EnterFrame(1 << FP, 0);
__ ReserveAlignedFrameSpace(0);
GenerateLoadFfiCallbackMetadataRuntimeFunction(
FfiCallbackMetadata::kGetFfiCallbackMetadata, R4);
__ blx(R4);
__ mov(THR, Operand(R0));
__ LeaveFrame(1 << FP);
// The trampoline type is at the top of the stack. Pop it into R4.
__ Pop(R4);
// Entry point is now at the top of the stack. Pop it into R5.
__ Pop(R5);
}
__ PopRegisters(argument_registers);
Label async_callback;
Label done;
// If GetFfiCallbackMetadata returned a null thread, it means that the async
// callback was invoked after it was deleted. In this case, do nothing.
__ cmp(THR, Operand(0));
__ b(&done, EQ);
// Check the trampoline type to see how the callback should be invoked.
__ cmp(
R4,
Operand(static_cast<uword>(FfiCallbackMetadata::TrampolineType::kAsync)));
__ b(&async_callback, EQ);
// Sync callback. The entry point contains the target function, so just call
// it. DLRT_GetThreadForNativeCallbackTrampoline exited the safepoint, so
// re-enter it afterwards.
// On entry to the function, there will be four extra slots on the stack:
// saved THR, R4, R5 and the return address. The target will know to skip
// them.
__ blx(R5);
// Clobbers R4, R5 and TMP, all saved or volatile.
__ EnterFullSafepoint(R4, R5);
__ b(&done);
__ Bind(&async_callback);
// Async callback. The entrypoint marshals the arguments into a message and
// sends it over the send port. DLRT_GetThreadForNativeCallbackTrampoline
// entered a temporary isolate, so exit it afterwards.
// On entry to the function, there will be four extra slots on the stack:
// saved THR, R4, R5 and the return address. The target will know to skip
// them.
__ blx(R5);
// Exit the temporary isolate.
{
__ EnterFrame(1 << FP, 0);
__ ReserveAlignedFrameSpace(0);
GenerateLoadFfiCallbackMetadataRuntimeFunction(
FfiCallbackMetadata::kExitTemporaryIsolate, R4);
__ blx(R4);
__ LeaveFrame(1 << FP);
}
__ Bind(&done);
// Returns.
__ PopList((1 << PC) | (1 << THR) | (1 << R4) | (1 << R5));
ASSERT_LESS_OR_EQUAL(__ CodeSize() - shared_stub_start,
FfiCallbackMetadata::kNativeCallbackSharedStubSize);
ASSERT_LESS_OR_EQUAL(__ CodeSize(), FfiCallbackMetadata::kPageSize);
#if defined(DEBUG)
while (__ CodeSize() < FfiCallbackMetadata::kPageSize) {
__ Breakpoint();
}
#endif
#endif
}
void StubCodeCompiler::GenerateDispatchTableNullErrorStub() {
__ EnterStubFrame();
__ SmiTag(DispatchTableNullErrorABI::kClassIdReg);
__ PushRegister(DispatchTableNullErrorABI::kClassIdReg);
__ CallRuntime(kDispatchTableNullErrorRuntimeEntry, /*argument_count=*/1);
// The NullError runtime entry does not return.
__ Breakpoint();
}
void StubCodeCompiler::GenerateRangeError(bool with_fpu_regs) {
auto perform_runtime_call = [&]() {
ASSERT(!GenericCheckBoundInstr::UseUnboxedRepresentation());
__ PushRegistersInOrder(
{RangeErrorABI::kLengthReg, RangeErrorABI::kIndexReg});
__ CallRuntime(kRangeErrorRuntimeEntry, /*argument_count=*/2);
__ Breakpoint();
};
GenerateSharedStubGeneric(
/*save_fpu_registers=*/with_fpu_regs,
with_fpu_regs
? target::Thread::range_error_shared_with_fpu_regs_stub_offset()
: target::Thread::range_error_shared_without_fpu_regs_stub_offset(),
/*allow_return=*/false, perform_runtime_call);
}
void StubCodeCompiler::GenerateWriteError(bool with_fpu_regs) {
auto perform_runtime_call = [&]() {
__ CallRuntime(kWriteErrorRuntimeEntry, /*argument_count=*/2);
__ Breakpoint();
};
GenerateSharedStubGeneric(
/*save_fpu_registers=*/with_fpu_regs,
with_fpu_regs
? target::Thread::write_error_shared_with_fpu_regs_stub_offset()
: target::Thread::write_error_shared_without_fpu_regs_stub_offset(),
/*allow_return=*/false, perform_runtime_call);
}
// Input parameters:
// LR : return address.
// SP : address of return value.
// R9 : address of the native function to call.
// R2 : address of first argument in argument array.
// R1 : argc_tag including number of arguments and function kind.
static void GenerateCallNativeWithWrapperStub(Assembler* assembler,
Address wrapper) {
const intptr_t thread_offset = target::NativeArguments::thread_offset();
const intptr_t argc_tag_offset = target::NativeArguments::argc_tag_offset();
const intptr_t argv_offset = target::NativeArguments::argv_offset();
const intptr_t retval_offset = target::NativeArguments::retval_offset();
__ EnterStubFrame();
// Save exit frame information to enable stack walking as we are about
// to transition to native code.
__ StoreToOffset(FP, THR, target::Thread::top_exit_frame_info_offset());
// Mark that the thread exited generated code through a runtime call.
__ LoadImmediate(R8, target::Thread::exit_through_runtime_call());
__ StoreToOffset(R8, THR, target::Thread::exit_through_ffi_offset());
#if defined(DEBUG)
{
Label ok;
// Check that we are always entering from Dart code.
__ LoadFromOffset(R8, THR, target::Thread::vm_tag_offset());
__ CompareImmediate(R8, VMTag::kDartTagId);
__ b(&ok, EQ);
__ Stop("Not coming from Dart code.");
__ Bind(&ok);
}
#endif
// Mark that the thread is executing native code.
__ StoreToOffset(R9, THR, target::Thread::vm_tag_offset());
// Reserve space for the native arguments structure passed on the stack (the
// outgoing pointer parameter to the native arguments structure is passed in
// R0) and align frame before entering the C++ world.
__ ReserveAlignedFrameSpace(target::NativeArguments::StructSize());
// Initialize target::NativeArguments structure and call native function.
// Registers R0, R1, R2, and R3 are used.
ASSERT(thread_offset == 0 * target::kWordSize);
// Set thread in NativeArgs.
__ mov(R0, Operand(THR));
ASSERT(argc_tag_offset == 1 * target::kWordSize);
// Set argc in target::NativeArguments: R1 already contains argc.
ASSERT(argv_offset == 2 * target::kWordSize);
// Set argv in target::NativeArguments: R2 already contains argv.
// Set retval in NativeArgs.
ASSERT(retval_offset == 3 * target::kWordSize);
__ add(R3, FP,
Operand((target::frame_layout.param_end_from_fp + 1) *
target::kWordSize));
// Passing the structure by value as in runtime calls would require changing
// Dart API for native functions.
// For now, space is reserved on the stack and we pass a pointer to it.
__ stm(IA, SP, (1 << R0) | (1 << R1) | (1 << R2) | (1 << R3));
__ mov(R0, Operand(SP)); // Pass the pointer to the target::NativeArguments.
__ mov(R1, Operand(R9)); // Pass the function entrypoint to call.
// Call native function invocation wrapper or redirection via simulator.
__ Call(wrapper);
// Mark that the thread is executing Dart code.
__ LoadImmediate(R2, VMTag::kDartTagId);
__ StoreToOffset(R2, THR, target::Thread::vm_tag_offset());
// Mark that the thread has not exited generated Dart code.
__ LoadImmediate(R2, 0);
__ StoreToOffset(R2, THR, target::Thread::exit_through_ffi_offset());
// Reset exit frame information in Isolate's mutator thread structure.
__ StoreToOffset(R2, THR, target::Thread::top_exit_frame_info_offset());
// Restore the global object pool after returning from runtime (old space is
// moving, so the GOP could have been relocated).
if (FLAG_precompiled_mode) {
__ SetupGlobalPoolAndDispatchTable();
}
__ LeaveStubFrame();
__ Ret();
}
void StubCodeCompiler::GenerateCallNoScopeNativeStub() {
GenerateCallNativeWithWrapperStub(
assembler,
Address(THR,
target::Thread::no_scope_native_wrapper_entry_point_offset()));
}
void StubCodeCompiler::GenerateCallAutoScopeNativeStub() {
GenerateCallNativeWithWrapperStub(
assembler,
Address(THR,
target::Thread::auto_scope_native_wrapper_entry_point_offset()));
}
// Input parameters:
// LR : return address.
// SP : address of return value.
// R9 : address of the native function to call.
// R2 : address of first argument in argument array.
// R1 : argc_tag including number of arguments and function kind.
void StubCodeCompiler::GenerateCallBootstrapNativeStub() {
GenerateCallNativeWithWrapperStub(
assembler,
Address(THR,
target::Thread::bootstrap_native_wrapper_entry_point_offset()));
}
// Input parameters:
// ARGS_DESC_REG: arguments descriptor array.
void StubCodeCompiler::GenerateCallStaticFunctionStub() {
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
// Setup space on stack for return value and preserve arguments descriptor.
__ LoadImmediate(R0, 0);
__ PushList((1 << R0) | (1 << ARGS_DESC_REG));
__ CallRuntime(kPatchStaticCallRuntimeEntry, 0);
// Get Code object result and restore arguments descriptor array.
__ PopList((1 << R0) | (1 << ARGS_DESC_REG));
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ mov(CODE_REG, Operand(R0));
__ Branch(FieldAddress(R0, target::Code::entry_point_offset()));
}
// Called from a static call only when an invalid code has been entered
// (invalid because its function was optimized or deoptimized).
// ARGS_DESC_REG: arguments descriptor array.
void StubCodeCompiler::GenerateFixCallersTargetStub() {
Label monomorphic;
__ BranchOnMonomorphicCheckedEntryJIT(&monomorphic);
// Load code pointer to this stub from the thread:
// The one that is passed in, is not correct - it points to the code object
// that needs to be replaced.
__ ldr(CODE_REG,
Address(THR, target::Thread::fix_callers_target_code_offset()));
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
// Setup space on stack for return value and preserve arguments descriptor.
__ LoadImmediate(R0, 0);
__ PushList((1 << R0) | (1 << ARGS_DESC_REG));
__ CallRuntime(kFixCallersTargetRuntimeEntry, 0);
// Get Code object result and restore arguments descriptor array.
__ PopList((1 << R0) | (1 << ARGS_DESC_REG));
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ mov(CODE_REG, Operand(R0));
__ Branch(FieldAddress(R0, target::Code::entry_point_offset()));
__ Bind(&monomorphic);
// Load code pointer to this stub from the thread:
// The one that is passed in, is not correct - it points to the code object
// that needs to be replaced.
__ ldr(CODE_REG,
Address(THR, target::Thread::fix_callers_target_code_offset()));
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
__ LoadImmediate(R1, 0);
__ Push(R1); // Result slot.
__ Push(R0); // Preserve receiver.
__ Push(R9); // Old cache value (also 2nd return value).
__ CallRuntime(kFixCallersTargetMonomorphicRuntimeEntry, 2);
__ Pop(R9); // Get target cache object.
__ Pop(R0); // Restore receiver.
__ Pop(CODE_REG); // Get target Code object.
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ Branch(FieldAddress(
CODE_REG, target::Code::entry_point_offset(CodeEntryKind::kMonomorphic)));
}
// Called from object allocate instruction when the allocation stub has been
// disabled.
void StubCodeCompiler::GenerateFixAllocationStubTargetStub() {
// Load code pointer to this stub from the thread:
// The one that is passed in, is not correct - it points to the code object
// that needs to be replaced.
__ ldr(CODE_REG,
Address(THR, target::Thread::fix_allocation_stub_code_offset()));
__ EnterStubFrame();
// Setup space on stack for return value.
__ LoadImmediate(R0, 0);
__ Push(R0);
__ CallRuntime(kFixAllocationStubTargetRuntimeEntry, 0);
// Get Code object result.
__ Pop(R0);
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ mov(CODE_REG, Operand(R0));
__ Branch(FieldAddress(R0, target::Code::entry_point_offset()));
}
// Called from object allocate instruction when the allocation stub for a
// generic class has been disabled.
void StubCodeCompiler::GenerateFixParameterizedAllocationStubTargetStub() {
// Load code pointer to this stub from the thread:
// The one that is passed in, is not correct - it points to the code object
// that needs to be replaced.
__ ldr(CODE_REG,
Address(THR, target::Thread::fix_allocation_stub_code_offset()));
__ EnterStubFrame();
// Preserve type arguments register.
__ Push(AllocateObjectABI::kTypeArgumentsReg);
// Setup space on stack for return value.
__ LoadImmediate(R0, 0);
__ Push(R0);
__ CallRuntime(kFixAllocationStubTargetRuntimeEntry, 0);
// Get Code object result.
__ Pop(R0);
// Restore type arguments register.
__ Push(AllocateObjectABI::kTypeArgumentsReg);
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ mov(CODE_REG, Operand(R0));
__ Branch(FieldAddress(R0, target::Code::entry_point_offset()));
}
// Input parameters:
// R2: smi-tagged argument count, may be zero.
// FP[target::frame_layout.param_end_from_fp + 1]: last argument.
static void PushArrayOfArguments(Assembler* assembler) {
// Allocate array to store arguments of caller.
__ LoadObject(R1, NullObject());
// R1: null element type for raw Array.
// R2: smi-tagged argument count, may be zero.
__ BranchLink(StubCodeAllocateArray());
// R0: newly allocated array.
// R2: smi-tagged argument count, may be zero (was preserved by the stub).
__ Push(R0); // Array is in R0 and on top of stack.
__ AddImmediate(R1, FP,
target::frame_layout.param_end_from_fp * target::kWordSize);
__ AddImmediate(R3, R0, target::Array::data_offset() - kHeapObjectTag);
// Copy arguments from stack to array (starting at the end).
// R1: address just beyond last argument on stack.
// R3: address of first argument in array.
Label enter;
__ b(&enter);
Label loop;
__ Bind(&loop);
__ ldr(R8, Address(R1, target::kWordSize, Address::PreIndex));
// Generational barrier is needed, array is not necessarily in new space.
__ StoreIntoObject(R0, Address(R3, R2, LSL, 1), R8);
__ Bind(&enter);
__ subs(R2, R2, Operand(target::ToRawSmi(1))); // R2 is Smi.
__ b(&loop, PL);
}
// Used by eager and lazy deoptimization. Preserve result in R0 if necessary.
// This stub translates optimized frame into unoptimized frame. The optimized
// frame can contain values in registers and on stack, the unoptimized
// frame contains all values on stack.
// Deoptimization occurs in following steps:
// - Push all registers that can contain values.
// - Call C routine to copy the stack and saved registers into temporary buffer.
// - Adjust caller's frame to correct unoptimized frame size.
// - Fill the unoptimized frame.
// - Materialize objects that require allocation (e.g. Double instances).
// GC can occur only after frame is fully rewritten.
// Stack after EnterFrame(...) below:
// +------------------+
// | Saved PP | <- TOS
// +------------------+
// | Saved FP | <- FP of stub
// +------------------+
// | Saved LR | (deoptimization point)
// +------------------+
// | pc marker |
// +------------------+
// | Saved CODE_REG |
// +------------------+
// | ... | <- SP of optimized frame
//
// Parts of the code cannot GC, part of the code can GC.
static void GenerateDeoptimizationSequence(Assembler* assembler,
DeoptStubKind kind) {
// DeoptimizeCopyFrame expects a Dart frame, i.e. EnterDartFrame(0), but there
// is no need to set the correct PC marker or load PP, since they get patched.
__ EnterDartFrame(0);
__ LoadPoolPointer();
// The code in this frame may not cause GC. kDeoptimizeCopyFrameRuntimeEntry
// and kDeoptimizeFillFrameRuntimeEntry are leaf runtime calls.
const intptr_t saved_result_slot_from_fp =
target::frame_layout.first_local_from_fp + 1 -
(kNumberOfCpuRegisters - R0);
const intptr_t saved_exception_slot_from_fp =
target::frame_layout.first_local_from_fp + 1 -
(kNumberOfCpuRegisters - R0);
const intptr_t saved_stacktrace_slot_from_fp =
target::frame_layout.first_local_from_fp + 1 -
(kNumberOfCpuRegisters - R1);
// Result in R0 is preserved as part of pushing all registers below.
// Push registers in their enumeration order: lowest register number at
// lowest address.
for (intptr_t i = kNumberOfCpuRegisters - 1; i >= 0; --i) {
if (i == CODE_REG) {
// Save the original value of CODE_REG pushed before invoking this stub
// instead of the value used to call this stub.
__ ldr(IP, Address(FP, 2 * target::kWordSize));
__ Push(IP);
} else if (i == SP) {
// Push(SP) has unpredictable behavior.
__ mov(IP, Operand(SP));
__ Push(IP);
} else {
__ Push(static_cast<Register>(i));
}
}
ASSERT(kFpuRegisterSize == 4 * target::kWordSize);
if (kNumberOfDRegisters > 16) {
__ vstmd(DB_W, SP, D16, kNumberOfDRegisters - 16);
__ vstmd(DB_W, SP, D0, 16);
} else {
__ vstmd(DB_W, SP, D0, kNumberOfDRegisters);
}
{
__ mov(R0, Operand(SP)); // Pass address of saved registers block.
LeafRuntimeScope rt(assembler,
/*frame_size=*/0,
/*preserve_registers=*/false);
bool is_lazy =
(kind == kLazyDeoptFromReturn) || (kind == kLazyDeoptFromThrow);
__ mov(R1, Operand(is_lazy ? 1 : 0));
rt.Call(kDeoptimizeCopyFrameRuntimeEntry, 2);
// Result (R0) is stack-size (FP - SP) in bytes.
}
if (kind == kLazyDeoptFromReturn) {
// Restore result into R1 temporarily.
__ ldr(R1, Address(FP, saved_result_slot_from_fp * target::kWordSize));
} else if (kind == kLazyDeoptFromThrow) {
// Restore result into R1 temporarily.
__ ldr(R1, Address(FP, saved_exception_slot_from_fp * target::kWordSize));
__ ldr(R2, Address(FP, saved_stacktrace_slot_from_fp * target::kWordSize));
}
__ RestoreCodePointer();
__ LeaveDartFrame();
__ sub(SP, FP, Operand(R0));
// DeoptimizeFillFrame expects a Dart frame, i.e. EnterDartFrame(0), but there
// is no need to set the correct PC marker or load PP, since they get patched.
__ EnterStubFrame();
if (kind == kLazyDeoptFromReturn) {
__ Push(R1); // Preserve result as first local.
} else if (kind == kLazyDeoptFromThrow) {
__ Push(R1); // Preserve exception as first local.
__ Push(R2); // Preserve stacktrace as second local.
}
{
__ mov(R0, Operand(FP)); // Get last FP address.
LeafRuntimeScope rt(assembler,
/*frame_size=*/0,
/*preserve_registers=*/false);
rt.Call(kDeoptimizeFillFrameRuntimeEntry, 1);
}
if (kind == kLazyDeoptFromReturn) {
// Restore result into R1.
__ ldr(R1, Address(FP, target::frame_layout.first_local_from_fp *
target::kWordSize));
} else if (kind == kLazyDeoptFromThrow) {
// Restore result into R1.
__ ldr(R1, Address(FP, target::frame_layout.first_local_from_fp *
target::kWordSize));
__ ldr(R2, Address(FP, (target::frame_layout.first_local_from_fp - 1) *
target::kWordSize));
}
// Code above cannot cause GC.
__ RestoreCodePointer();
__ LeaveStubFrame();
// Frame is fully rewritten at this point and it is safe to perform a GC.
// Materialize any objects that were deferred by FillFrame because they
// require allocation.
// Enter stub frame with loading PP. The caller's PP is not materialized yet.
__ EnterStubFrame();
if (kind == kLazyDeoptFromReturn) {
__ Push(R1); // Preserve result, it will be GC-d here.
} else if (kind == kLazyDeoptFromThrow) {
// Preserve CODE_REG for one more runtime call.
__ Push(CODE_REG);
__ Push(R1); // Preserve exception, it will be GC-d here.
__ Push(R2); // Preserve stacktrace, it will be GC-d here.
}
__ PushObject(NullObject()); // Space for the result.
__ CallRuntime(kDeoptimizeMaterializeRuntimeEntry, 0);
// Result tells stub how many bytes to remove from the expression stack
// of the bottom-most frame. They were used as materialization arguments.
__ Pop(R2);
if (kind == kLazyDeoptFromReturn) {
__ Pop(R0); // Restore result.
} else if (kind == kLazyDeoptFromThrow) {
__ Pop(R1); // Restore stacktrace.
__ Pop(R0); // Restore exception.
__ Pop(CODE_REG);
}
__ LeaveStubFrame();
// Remove materialization arguments.
__ add(SP, SP, Operand(R2, ASR, kSmiTagSize));
// The caller is responsible for emitting the return instruction.
if (kind == kLazyDeoptFromThrow) {
// Unoptimized frame is now ready to accept the exception. Rethrow it to
// find the right handler. Ask rethrow machinery to bypass debugger it
// was already notified about this exception.
__ EnterStubFrame();
__ PushImmediate(
target::ToRawSmi(0)); // Space for the return value (unused).
__ Push(R0); // Exception
__ Push(R1); // Stacktrace
__ PushImmediate(target::ToRawSmi(1)); // Bypass debugger
__ CallRuntime(kReThrowRuntimeEntry, 3);
__ LeaveStubFrame();
}
}
// R0: result, must be preserved
void StubCodeCompiler::GenerateDeoptimizeLazyFromReturnStub() {
// Push zap value instead of CODE_REG for lazy deopt.
__ LoadImmediate(IP, kZapCodeReg);
__ Push(IP);
// Return address for "call" to deopt stub.
WRITES_RETURN_ADDRESS_TO_LR(__ LoadImmediate(LR, kZapReturnAddress));
__ ldr(CODE_REG,
Address(THR, target::Thread::lazy_deopt_from_return_stub_offset()));
GenerateDeoptimizationSequence(assembler, kLazyDeoptFromReturn);
__ Ret();
}
// R0: exception, must be preserved
// R1: stacktrace, must be preserved
void StubCodeCompiler::GenerateDeoptimizeLazyFromThrowStub() {
// Push zap value instead of CODE_REG for lazy deopt.
__ LoadImmediate(IP, kZapCodeReg);
__ Push(IP);
// Return address for "call" to deopt stub.
WRITES_RETURN_ADDRESS_TO_LR(__ LoadImmediate(LR, kZapReturnAddress));
__ ldr(CODE_REG,
Address(THR, target::Thread::lazy_deopt_from_throw_stub_offset()));
GenerateDeoptimizationSequence(assembler, kLazyDeoptFromThrow);
__ Ret();
}
void StubCodeCompiler::GenerateDeoptimizeStub() {
__ Push(CODE_REG);
__ ldr(CODE_REG, Address(THR, target::Thread::deoptimize_stub_offset()));
GenerateDeoptimizationSequence(assembler, kEagerDeopt);
__ Ret();
}
// IC_DATA_REG: ICData/MegamorphicCache
static void GenerateNoSuchMethodDispatcherBody(Assembler* assembler) {
__ EnterStubFrame();
__ ldr(ARGS_DESC_REG,
FieldAddress(IC_DATA_REG,
target::CallSiteData::arguments_descriptor_offset()));
// Load the receiver.
__ ldr(R2, FieldAddress(ARGS_DESC_REG,
target::ArgumentsDescriptor::size_offset()));
__ add(IP, FP, Operand(R2, LSL, 1)); // R2 is Smi.
__ ldr(R8, Address(IP, target::frame_layout.param_end_from_fp *
target::kWordSize));
__ LoadImmediate(IP, 0);
__ Push(IP); // Result slot.
__ Push(R8); // Receiver.
__ Push(IC_DATA_REG); // ICData/MegamorphicCache.
__ Push(ARGS_DESC_REG); // Arguments descriptor.
// Adjust arguments count.
__ ldr(R3, FieldAddress(ARGS_DESC_REG,
target::ArgumentsDescriptor::type_args_len_offset()));
__ cmp(R3, Operand(0));
__ AddImmediate(R2, R2, target::ToRawSmi(1),
NE); // Include the type arguments.
// R2: Smi-tagged arguments array length.
PushArrayOfArguments(assembler);
const intptr_t kNumArgs = 4;
__ CallRuntime(kNoSuchMethodFromCallStubRuntimeEntry, kNumArgs);
__ Drop(4);
__ Pop(R0); // Return value.
__ LeaveStubFrame();
__ Ret();
}
static void GenerateDispatcherCode(Assembler* assembler,
Label* call_target_function) {
__ Comment("NoSuchMethodDispatch");
// When lazily generated invocation dispatchers are disabled, the
// miss-handler may return null.
__ CompareObject(R0, NullObject());
__ b(call_target_function, NE);
GenerateNoSuchMethodDispatcherBody(assembler);
}
// Input:
// ARGS_DESC_REG - arguments descriptor
// IC_DATA_REG - icdata/megamorphic_cache
void StubCodeCompiler::GenerateNoSuchMethodDispatcherStub() {
GenerateNoSuchMethodDispatcherBody(assembler);
}
// Called for inline allocation of arrays.
// Input registers (preserved):
// LR: return address.
// AllocateArrayABI::kLengthReg: array length as Smi.
// AllocateArrayABI::kTypeArgumentsReg: type arguments of array.
// Output registers:
// AllocateArrayABI::kResultReg: newly allocated array.
// Clobbered:
// R3, R4, R8, R9
void StubCodeCompiler::GenerateAllocateArrayStub() {
if (!FLAG_use_slow_path && FLAG_inline_alloc) {
Label slow_case;
// Compute the size to be allocated, it is based on the array length
// and is computed as:
// RoundedAllocationSize(
// (array_length * kwordSize) + target::Array::header_size()).
__ mov(R3, Operand(AllocateArrayABI::kLengthReg)); // Array length.
// Check that length is a Smi.
__ tst(R3, Operand(kSmiTagMask));
__ b(&slow_case, NE);
// Check length >= 0 && length <= kMaxNewSpaceElements
const intptr_t max_len =
target::ToRawSmi(target::Array::kMaxNewSpaceElements);
__ CompareImmediate(R3, max_len);
__ b(&slow_case, HI);
const intptr_t cid = kArrayCid;
NOT_IN_PRODUCT(__ MaybeTraceAllocation(cid, &slow_case, R4));
const intptr_t fixed_size_plus_alignment_padding =
target::Array::header_size() +
target::ObjectAlignment::kObjectAlignment - 1;
__ LoadImmediate(R9, fixed_size_plus_alignment_padding);
__ add(R9, R9, Operand(R3, LSL, 1)); // R3 is a Smi.
ASSERT(kSmiTagShift == 1);
__ bic(R9, R9, Operand(target::ObjectAlignment::kObjectAlignment - 1));
// R9: Allocation size.
// Potential new object start.
__ ldr(AllocateArrayABI::kResultReg,
Address(THR, target::Thread::top_offset()));
__ adds(R3, AllocateArrayABI::kResultReg,
Operand(R9)); // Potential next object start.
__ b(&slow_case, CS); // Branch if unsigned overflow.
// Check if the allocation fits into the remaining space.
// AllocateArrayABI::kResultReg: potential new object start.
// R3: potential next object start.
// R9: allocation size.
__ ldr(TMP, Address(THR, target::Thread::end_offset()));
__ cmp(R3, Operand(TMP));
__ b(&slow_case, CS);
__ CheckAllocationCanary(AllocateArrayABI::kResultReg);
// Successfully allocated the object(s), now update top to point to
// next object start and initialize the object.
__ str(R3, Address(THR, target::Thread::top_offset()));
__ add(AllocateArrayABI::kResultReg, AllocateArrayABI::kResultReg,
Operand(kHeapObjectTag));
// Initialize the tags.
// AllocateArrayABI::kResultReg: new object start as a tagged pointer.
// R3: new object end address.
// R9: allocation size.
{
const intptr_t shift = target::UntaggedObject::kTagBitsSizeTagPos -
target::ObjectAlignment::kObjectAlignmentLog2;
__ CompareImmediate(R9, target::UntaggedObject::kSizeTagMaxSizeTag);
__ mov(R8, Operand(R9, LSL, shift), LS);
__ mov(R8, Operand(0), HI);
// Get the class index and insert it into the tags.
// R8: size and bit tags.
const uword tags =
target::MakeTagWordForNewSpaceObject(cid, /*instance_size=*/0);
__ LoadImmediate(TMP, tags);
__ orr(R8, R8, Operand(TMP));
__ InitializeHeader(R8, AllocateArrayABI::kResultReg);
}
// AllocateArrayABI::kResultReg: new object start as a tagged pointer.
// R3: new object end address.
// Store the type argument field.
__ StoreIntoObjectNoBarrier(
AllocateArrayABI::kResultReg,
FieldAddress(AllocateArrayABI::kResultReg,
target::Array::type_arguments_offset()),
AllocateArrayABI::kTypeArgumentsReg);
// Set the length field.
__ StoreIntoObjectNoBarrier(AllocateArrayABI::kResultReg,
FieldAddress(AllocateArrayABI::kResultReg,
target::Array::length_offset()),
AllocateArrayABI::kLengthReg);
// Initialize all array elements to raw_null.
// AllocateArrayABI::kResultReg: new object start as a tagged pointer.
// R8, R9: null
// R4: iterator which initially points to the start of the variable
// data area to be initialized.
// R3: new object end address.
// R9: allocation size.
__ LoadObject(R8, NullObject());
__ mov(R9, Operand(R8));
__ AddImmediate(R4, AllocateArrayABI::kResultReg,
target::Array::header_size() - kHeapObjectTag);
__ InitializeFieldsNoBarrier(AllocateArrayABI::kResultReg, R4, R3, R8, R9);
__ Ret();
// Unable to allocate the array using the fast inline code, just call
// into the runtime.
__ Bind(&slow_case);
}
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
__ LoadImmediate(TMP, 0);
// Setup space on stack for return value.
// Push array length as Smi and element type.
__ PushList((1 << AllocateArrayABI::kTypeArgumentsReg) |
(1 << AllocateArrayABI::kLengthReg) | (1 << IP));
__ CallRuntime(kAllocateArrayRuntimeEntry, 2);
// Write-barrier elimination might be enabled for this array (depending on the
// array length). To be sure we will check if the allocated object is in old
// space and if so call a leaf runtime to add it to the remembered set.
__ ldr(AllocateArrayABI::kResultReg, Address(SP, 2 * target::kWordSize));
EnsureIsNewOrRemembered();
// Pop arguments; result is popped in IP.
__ PopList((1 << AllocateArrayABI::kTypeArgumentsReg) |
(1 << AllocateArrayABI::kLengthReg) | (1 << IP));
__ mov(AllocateArrayABI::kResultReg, Operand(IP));
__ LeaveStubFrame();
__ Ret();
}
// Called for allocation of Mint.
void StubCodeCompiler::GenerateAllocateMintSharedWithFPURegsStub() {
// For test purpose call allocation stub without inline allocation attempt.
if (!FLAG_use_slow_path && FLAG_inline_alloc) {
Label slow_case;
__ TryAllocate(compiler::MintClass(), &slow_case, Assembler::kNearJump,
AllocateMintABI::kResultReg, AllocateMintABI::kTempReg);
__ Ret();
__ Bind(&slow_case);
}
COMPILE_ASSERT(AllocateMintABI::kResultReg ==
SharedSlowPathStubABI::kResultReg);
GenerateSharedStub(/*save_fpu_registers=*/true, &kAllocateMintRuntimeEntry,
target::Thread::allocate_mint_with_fpu_regs_stub_offset(),
/*allow_return=*/true,
/*store_runtime_result_in_result_register=*/true);
}
// Called for allocation of Mint.
void StubCodeCompiler::GenerateAllocateMintSharedWithoutFPURegsStub() {
// For test purpose call allocation stub without inline allocation attempt.
if (!FLAG_use_slow_path && FLAG_inline_alloc) {
Label slow_case;
__ TryAllocate(compiler::MintClass(), &slow_case, Assembler::kNearJump,
AllocateMintABI::kResultReg, AllocateMintABI::kTempReg);
__ Ret();
__ Bind(&slow_case);
}
COMPILE_ASSERT(AllocateMintABI::kResultReg ==
SharedSlowPathStubABI::kResultReg);
GenerateSharedStub(
/*save_fpu_registers=*/false, &kAllocateMintRuntimeEntry,
target::Thread::allocate_mint_without_fpu_regs_stub_offset(),
/*allow_return=*/true,
/*store_runtime_result_in_result_register=*/true);
}
// Called when invoking Dart code from C++ (VM code).
// Input parameters:
// LR : points to return address.
// R0 : target code or entry point (in AOT mode).
// R1 : arguments descriptor array.
// R2 : arguments array.
// R3 : current thread.
void StubCodeCompiler::GenerateInvokeDartCodeStub() {
SPILLS_LR_TO_FRAME(__ EnterFrame((1 << FP) | (1 << LR), 0));
// Push code object to PC marker slot.
__ ldr(IP, Address(R3, target::Thread::invoke_dart_code_stub_offset()));
__ Push(IP);
__ PushNativeCalleeSavedRegisters();
// Set up THR, which caches the current thread in Dart code.
if (THR != R3) {
__ mov(THR, Operand(R3));
}
#if defined(USING_SHADOW_CALL_STACK)
#error Unimplemented
#endif
// Save the current VMTag on the stack.
__ LoadFromOffset(R9, THR, target::Thread::vm_tag_offset());
__ Push(R9);
// Save top resource and top exit frame info. Use R4-6 as temporary registers.
// StackFrameIterator reads the top exit frame info saved in this frame.
__ LoadFromOffset(R4, THR, target::Thread::top_resource_offset());
__ Push(R4);
__ LoadImmediate(R8, 0);
__ StoreToOffset(R8, THR, target::Thread::top_resource_offset());
__ LoadFromOffset(R8, THR, target::Thread::exit_through_ffi_offset());
__ Push(R8);
__ LoadImmediate(R8, 0);
__ StoreToOffset(R8, THR, target::Thread::exit_through_ffi_offset());
__ LoadFromOffset(R9, THR, target::Thread::top_exit_frame_info_offset());
__ StoreToOffset(R8, THR, target::Thread::top_exit_frame_info_offset());
// target::frame_layout.exit_link_slot_from_entry_fp must be kept in sync
// with the code below.
#if defined(DART_TARGET_OS_MACOS) || defined(DART_TARGET_OS_MACOS_IOS)
ASSERT(target::frame_layout.exit_link_slot_from_entry_fp == -27);
#else
ASSERT(target::frame_layout.exit_link_slot_from_entry_fp == -28);
#endif
__ Push(R9);
__ EmitEntryFrameVerification(R9);
// Mark that the thread is executing Dart code. Do this after initializing the
// exit link for the profiler.
__ LoadImmediate(R9, VMTag::kDartTagId);
__ StoreToOffset(R9, THR, target::Thread::vm_tag_offset());
// Load arguments descriptor array into R4, which is passed to Dart code.
__ mov(R4, Operand(R1));
// Load number of arguments into R9 and adjust count for type arguments.
__ ldr(R3,
FieldAddress(R4, target::ArgumentsDescriptor::type_args_len_offset()));
__ ldr(R9, FieldAddress(R4, target::ArgumentsDescriptor::count_offset()));
__ cmp(R3, Operand(0));
__ AddImmediate(R9, R9, target::ToRawSmi(1),
NE); // Include the type arguments.
__ SmiUntag(R9);
// Compute address of 'arguments array' data area into R2.
__ AddImmediate(R2, R2, target::Array::data_offset() - kHeapObjectTag);
// Set up arguments for the Dart call.
Label push_arguments;
Label done_push_arguments;
__ CompareImmediate(R9, 0); // check if there are arguments.
__ b(&done_push_arguments, EQ);
__ LoadImmediate(R1, 0);
__ Bind(&push_arguments);
__ ldr(R3, Address(R2));
__ Push(R3);
__ AddImmediate(R2, target::kWordSize);
__ AddImmediate(R1, 1);
__ cmp(R1, Operand(R9));
__ b(&push_arguments, LT);
__ Bind(&done_push_arguments);
// Call the Dart code entrypoint.
if (FLAG_precompiled_mode) {
__ SetupGlobalPoolAndDispatchTable();
__ LoadImmediate(CODE_REG, 0); // GC safe value into CODE_REG.
} else {
__ LoadImmediate(PP, 0); // GC safe value into PP.
__ mov(CODE_REG, Operand(R0));
__ ldr(R0, FieldAddress(CODE_REG, target::Code::entry_point_offset()));
}
__ blx(R0); // R4 is the arguments descriptor array.
// Get rid of arguments pushed on the stack.
__ AddImmediate(
SP, FP,
target::frame_layout.exit_link_slot_from_entry_fp * target::kWordSize);
// Restore the saved top exit frame info and top resource back into the
// Isolate structure. Uses R9 as a temporary register for this.
__ Pop(R9);
__ StoreToOffset(R9, THR, target::Thread::top_exit_frame_info_offset());
__ Pop(R9);
__ StoreToOffset(R9, THR, target::Thread::exit_through_ffi_offset());
__ Pop(R9);
__ StoreToOffset(R9, THR, target::Thread::top_resource_offset());
// Restore the current VMTag from the stack.
__ Pop(R4);
__ StoreToOffset(R4, THR, target::Thread::vm_tag_offset());
#if defined(USING_SHADOW_CALL_STACK)
#error Unimplemented
#endif
__ PopNativeCalleeSavedRegisters();
__ set_constant_pool_allowed(false);
// Restore the frame pointer and return.
RESTORES_LR_FROM_FRAME(__ LeaveFrame((1 << FP) | (1 << LR)));
__ Ret();
}
// Called when invoking compiled Dart code from interpreted Dart code.
// Input parameters:
// LR : points to return address.
// R0 : target code or entry point (in AOT mode).
// R1 : arguments descriptor array.
// R2 : address of first argument.
// R3 : current thread.
void StubCodeCompiler::GenerateInvokeDartCodeFromBytecodeStub() {
#if defined(DART_DYNAMIC_MODULES)
SPILLS_LR_TO_FRAME(__ EnterFrame((1 << FP) | (1 << LR), 0));
// Push code object to PC marker slot.
__ ldr(IP,
Address(R3,
target::Thread::invoke_dart_code_from_bytecode_stub_offset()));
__ Push(IP);
__ PushNativeCalleeSavedRegisters();
// Set up THR, which caches the current thread in Dart code.
if (THR != R3) {
__ mov(THR, Operand(R3));
}
#if defined(USING_SHADOW_CALL_STACK)
#error Unimplemented
#endif
// Save the current VMTag on the stack.
__ LoadFromOffset(R9, THR, target::Thread::vm_tag_offset());
__ Push(R9);
// Save top resource and top exit frame info. Use R4-6 as temporary registers.
// StackFrameIterator reads the top exit frame info saved in this frame.
__ LoadFromOffset(R4, THR, target::Thread::top_resource_offset());
__ Push(R4);
__ LoadImmediate(R8, 0);
__ StoreToOffset(R8, THR, target::Thread::top_resource_offset());
__ LoadFromOffset(R8, THR, target::Thread::exit_through_ffi_offset());
__ Push(R8);
__ LoadImmediate(R8, 0);
__ StoreToOffset(R8, THR, target::Thread::exit_through_ffi_offset());
__ LoadFromOffset(R9, THR, target::Thread::top_exit_frame_info_offset());
__ StoreToOffset(R8, THR, target::Thread::top_exit_frame_info_offset());
// target::frame_layout.exit_link_slot_from_entry_fp must be kept in sync
// with the code below.
#if defined(DART_TARGET_OS_MACOS) || defined(DART_TARGET_OS_MACOS_IOS)
ASSERT(target::frame_layout.exit_link_slot_from_entry_fp == -27);
#else
ASSERT(target::frame_layout.exit_link_slot_from_entry_fp == -28);
#endif
__ Push(R9);
__ EmitEntryFrameVerification(R9);
// Mark that the thread is executing Dart code. Do this after initializing the
// exit link for the profiler.
__ LoadImmediate(R9, VMTag::kDartTagId);
__ StoreToOffset(R9, THR, target::Thread::vm_tag_offset());
// Load arguments descriptor array into R4, which is passed to Dart code.
__ mov(R4, Operand(R1));
// Load number of arguments into R9 and adjust count for type arguments.
__ ldr(R3,
FieldAddress(R4, target::ArgumentsDescriptor::type_args_len_offset()));
__ ldr(R9, FieldAddress(R4, target::ArgumentsDescriptor::count_offset()));
__ cmp(R3, Operand(0));
__ AddImmediate(R9, R9, target::ToRawSmi(1),
NE); // Include the type arguments.
__ SmiUntag(R9);
// R2 points to first argument.
// Set up arguments for the Dart call.
Label push_arguments;
Label done_push_arguments;
__ CompareImmediate(R9, 0); // check if there are arguments.
__ b(&done_push_arguments, EQ);
__ LoadImmediate(R1, 0);
__ Bind(&push_arguments);
__ ldr(R3, Address(R2));
__ Push(R3);
__ AddImmediate(R2, target::kWordSize);
__ AddImmediate(R1, 1);
__ cmp(R1, Operand(R9));
__ b(&push_arguments, LT);
__ Bind(&done_push_arguments);
// Call the Dart code entrypoint.
if (FLAG_precompiled_mode) {
__ SetupGlobalPoolAndDispatchTable();
__ LoadImmediate(CODE_REG, 0); // GC safe value into CODE_REG.
} else {
__ LoadImmediate(PP, 0); // GC safe value into PP.
__ mov(CODE_REG, Operand(R0));
__ ldr(R0, FieldAddress(CODE_REG, target::Code::entry_point_offset()));
}
__ blx(R0); // R4 is the arguments descriptor array.
// Get rid of arguments pushed on the stack.
__ AddImmediate(
SP, FP,
target::frame_layout.exit_link_slot_from_entry_fp * target::kWordSize);
// Restore the saved top exit frame info and top resource back into the
// Isolate structure. Uses R9 as a temporary register for this.
__ Pop(R9);
__ StoreToOffset(R9, THR, target::Thread::top_exit_frame_info_offset());
__ Pop(R9);
__ StoreToOffset(R9, THR, target::Thread::exit_through_ffi_offset());
__ Pop(R9);
__ StoreToOffset(R9, THR, target::Thread::top_resource_offset());
// Restore the current VMTag from the stack.
__ Pop(R4);
__ StoreToOffset(R4, THR, target::Thread::vm_tag_offset());
#if defined(USING_SHADOW_CALL_STACK)
#error Unimplemented
#endif
__ PopNativeCalleeSavedRegisters();
__ set_constant_pool_allowed(false);
// Restore the frame pointer and return.
RESTORES_LR_FROM_FRAME(__ LeaveFrame((1 << FP) | (1 << LR)));
__ Ret();
#else
__ Stop("Not using Dart dynamic modules");
#endif // defined(DART_DYNAMIC_MODULES)
}
// Helper to generate space allocation of context stub.
// This does not initialise the fields of the context.
// Input:
// R1: number of context variables.
// Output:
// R0: new allocated Context object.
// Clobbered:
// R2, R3, R8, R9
static void GenerateAllocateContext(Assembler* assembler, Label* slow_case) {
// First compute the rounded instance size.
// R1: number of context variables.
const intptr_t fixed_size_plus_alignment_padding =
target::Context::header_size() +
target::ObjectAlignment::kObjectAlignment - 1;
__ LoadImmediate(R2, fixed_size_plus_alignment_padding);
__ add(R2, R2, Operand(R1, LSL, 2));
ASSERT(kSmiTagShift == 1);
__ bic(R2, R2, Operand(target::ObjectAlignment::kObjectAlignment - 1));
NOT_IN_PRODUCT(__ MaybeTraceAllocation(kContextCid, slow_case, R8));
// Now allocate the object.
// R1: number of context variables.
// R2: object size.
__ ldr(R0, Address(THR, target::Thread::top_offset()));
__ add(R3, R2, Operand(R0));
// Check if the allocation fits into the remaining space.
// R0: potential new object.
// R1: number of context variables.
// R2: object size.
// R3: potential next object start.
__ ldr(IP, Address(THR, target::Thread::end_offset()));
__ cmp(R3, Operand(IP));
__ b(slow_case, CS); // Branch if unsigned higher or equal.
__ CheckAllocationCanary(R0);
// Successfully allocated the object, now update top to point to
// next object start and initialize the object.
// R0: new object start (untagged).
// R1: number of context variables.
// R2: object size.
// R3: next object start.
__ str(R3, Address(THR, target::Thread::top_offset()));
__ add(R0, R0, Operand(kHeapObjectTag));
// Calculate the size tag.
// R0: new object (tagged).
// R1: number of context variables.
// R2: object size.
// R3: next object start.
const intptr_t shift = target::UntaggedObject::kTagBitsSizeTagPos -
target::ObjectAlignment::kObjectAlignmentLog2;
__ CompareImmediate(R2, target::UntaggedObject::kSizeTagMaxSizeTag);
// If no size tag overflow, shift R2 left, else set R2 to zero.
__ mov(R9, Operand(R2, LSL, shift), LS);
__ mov(R9, Operand(0), HI);
// Get the class index and insert it into the tags.
// R9: size and bit tags.
const uword tags =
target::MakeTagWordForNewSpaceObject(kContextCid, /*instance_size=*/0);
__ LoadImmediate(IP, tags);
__ orr(R9, R9, Operand(IP));
__ InitializeHeader(R9, R0);
// Setup up number of context variables field.
// R0: new object.
// R1: number of context variables as integer value (not object).
// R2: object size.
// R3: next object start.
__ str(R1, FieldAddress(R0, target::Context::num_variables_offset()));
}
// Called for inline allocation of contexts.
// Input:
// R1: number of context variables.
// Output:
// R0: new allocated Context object.
// Clobbered:
// Potentially any since is can go to runtime.
void StubCodeCompiler::GenerateAllocateContextStub() {
if (!FLAG_use_slow_path && FLAG_inline_alloc) {
Label slow_case;
GenerateAllocateContext(assembler, &slow_case);
// Setup the parent field.
// R0: new object.
// R2: object size.
// R3: next object start.
__ LoadObject(R8, NullObject());
__ MoveRegister(R9, R8); // Needed for InitializeFieldsNoBarrier.
__ StoreIntoObjectNoBarrier(
R0, FieldAddress(R0, target::Context::parent_offset()), R8);
// Initialize the context variables.
// R0: new object.
// R2: object size.
// R3: next object start.
// R8, R9: raw null.
__ AddImmediate(R1, R0,
target::Context::variable_offset(0) - kHeapObjectTag);
__ InitializeFieldsNoBarrier(R0, R1, R3, R8, R9);
// Done allocating and initializing the context.
// R0: new object.
__ Ret();
__ Bind(&slow_case);
}
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
// Setup space on stack for return value.
__ LoadImmediate(R2, 0);
__ SmiTag(R1);
__ PushList((1 << R1) | (1 << R2));
__ CallRuntime(kAllocateContextRuntimeEntry, 1); // Allocate context.
__ Drop(1); // Pop number of context variables argument.
__ Pop(R0); // Pop the new context object.
// Write-barrier elimination might be enabled for this context (depending on
// the size). To be sure we will check if the allocated object is in old
// space and if so call a leaf runtime to add it to the remembered set.
EnsureIsNewOrRemembered();
// R0: new object
// Restore the frame pointer.
__ LeaveStubFrame();
__ Ret();
}
// Called for clone of contexts.
// Input:
// R4: context variable to clone.
// Output:
// R0: new allocated Context object.
// Clobbered:
// Potentially any since it can go to runtime.
void StubCodeCompiler::GenerateCloneContextStub() {
if (!FLAG_use_slow_path && FLAG_inline_alloc) {
Label slow_case;
// Load num. variable in the existing context.
__ ldr(R1, FieldAddress(R4, target::Context::num_variables_offset()));
GenerateAllocateContext(assembler, &slow_case);
// Load parent in the existing context.
__ ldr(R2, FieldAddress(R4, target::Context::parent_offset()));
// Setup the parent field.
// R0: new object.
__ StoreIntoObjectNoBarrier(
R0, FieldAddress(R0, target::Context::parent_offset()), R2);
// Clone the context variables.
// R0: new object.
// R1: number of context variables.
{
Label loop, done;
__ AddImmediate(R2, R0,
target::Context::variable_offset(0) - kHeapObjectTag);
__ AddImmediate(R3, R4,
target::Context::variable_offset(0) - kHeapObjectTag);
__ Bind(&loop);
__ subs(R1, R1, Operand(1));
__ b(&done, MI);
__ ldr(R9, Address(R3, R1, LSL, target::kWordSizeLog2));
__ str(R9, Address(R2, R1, LSL, target::kWordSizeLog2));
__ b(&loop, NE); // Loop if R1 not zero.
__ Bind(&done);
}
// Done allocating and initializing the context.
// R0: new object.
__ Ret();
__ Bind(&slow_case);
}
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
// Setup space on stack for return value.
__ LoadImmediate(R0, 0);
__ PushRegisterPair(R4, R0);
__ CallRuntime(kCloneContextRuntimeEntry, 1); // Clone context.
// R4: Pop number of context variables argument.
// R0: Pop the new context object.
__ PopRegisterPair(R4, R0);
// Write-barrier elimination might be enabled for this context (depending on
// the size). To be sure we will check if the allocated object is in old
// space and if so call a leaf runtime to add it to the remembered set.
EnsureIsNewOrRemembered();
// R0: new object
// Restore the frame pointer.
__ LeaveStubFrame();
__ Ret();
}
void StubCodeCompiler::GenerateWriteBarrierWrappersStub() {
for (intptr_t i = 0; i < kNumberOfCpuRegisters; ++i) {
if ((kDartAvailableCpuRegs & (1 << i)) == 0) continue;
Register reg = static_cast<Register>(i);
intptr_t start = __ CodeSize();
SPILLS_LR_TO_FRAME(__ PushList((1 << LR) | (1 << kWriteBarrierObjectReg)));
__ mov(kWriteBarrierObjectReg, Operand(reg));
__ Call(Address(THR, target::Thread::write_barrier_entry_point_offset()));
RESTORES_LR_FROM_FRAME(
__ PopList((1 << LR) | (1 << kWriteBarrierObjectReg)));
READS_RETURN_ADDRESS_FROM_LR(__ bx(LR));
intptr_t end = __ CodeSize();
RELEASE_ASSERT(end - start == kStoreBufferWrapperSize);
}
}
// Helper stub to implement Assembler::StoreIntoObject.
// Input parameters:
// R1: Object (old)
// R0: Value (old or new)
// R9: Slot
// If R0 is new, add R1 to the store buffer. Otherwise R0 is old, mark R0
// and add it to the mark list.
COMPILE_ASSERT(kWriteBarrierObjectReg == R1);
COMPILE_ASSERT(kWriteBarrierValueReg == R0);
COMPILE_ASSERT(kWriteBarrierSlotReg == R9);
static void GenerateWriteBarrierStubHelper(Assembler* assembler, bool cards) {
Label skip_marking;
__ Push(R2);
__ ldr(TMP, FieldAddress(R0, target::Object::tags_offset()));
__ ldr(R2, Address(THR, target::Thread::write_barrier_mask_offset()));
__ and_(TMP, TMP, Operand(R2));
__ Pop(R2);
__ tst(TMP, Operand(target::UntaggedObject::kIncrementalBarrierMask));
__ b(&skip_marking, ZERO);
{
// Atomically clear kNotMarkedBit.
Label retry, is_new, done;
__ PushList((1 << R2) | (1 << R3) | (1 << R4)); // Spill.
__ AddImmediate(R3, R0, target::Object::tags_offset() - kHeapObjectTag);
// R3: Untagged address of header word (ldrex/strex do not support offsets).
__ Bind(&retry);
__ ldrex(R2, R3);
__ tst(R2, Operand(1 << target::UntaggedObject::kNotMarkedBit));
__ b(&done, ZERO); // Marked by another thread.
__ bic(R2, R2, Operand(1 << target::UntaggedObject::kNotMarkedBit));
__ strex(R4, R2, R3);
__ cmp(R4, Operand(1));
__ b(&retry, EQ);
__ tst(R0, Operand(1 << target::ObjectAlignment::kNewObjectBitPosition));
__ b(&is_new, NOT_ZERO);
auto mark_stack_push = [&](intptr_t offset, const RuntimeEntry& entry) {
__ ldr(R4, Address(THR, offset));
__ ldr(R2, Address(R4, target::MarkingStackBlock::top_offset()));
__ add(R3, R4, Operand(R2, LSL, target::kWordSizeLog2));
__ str(R0, Address(R3, target::MarkingStackBlock::pointers_offset()));
__ add(R2, R2, Operand(1));
__ str(R2, Address(R4, target::MarkingStackBlock::top_offset()));
__ CompareImmediate(R2, target::MarkingStackBlock::kSize);
__ b(&done, NE);
{
LeafRuntimeScope rt(assembler, /*frame_size=*/0,
/*preserve_registers=*/true);
__ mov(R0, Operand(THR));
rt.Call(entry, 1);
}
};
mark_stack_push(target::Thread::old_marking_stack_block_offset(),
kOldMarkingStackBlockProcessRuntimeEntry);
__ b(&done);
__ Bind(&is_new);
mark_stack_push(target::Thread::new_marking_stack_block_offset(),
kNewMarkingStackBlockProcessRuntimeEntry);
__ Bind(&done);
__ clrex();
__ PopList((1 << R2) | (1 << R3) | (1 << R4)); // Unspill.
}
Label add_to_remembered_set, remember_card;
__ Bind(&skip_marking);
__ Push(R2);
__ ldr(TMP, FieldAddress(R1, target::Object::tags_offset()));
__ ldr(R2, FieldAddress(R0, target::Object::tags_offset()));
__ and_(TMP, R2,
Operand(TMP, LSR, target::UntaggedObject::kBarrierOverlapShift));
__ Pop(R2);
__ tst(TMP, Operand(target::UntaggedObject::kGenerationalBarrierMask));
__ b(&add_to_remembered_set, NOT_ZERO);
__ Ret();
__ Bind(&add_to_remembered_set);
if (cards) {
__ ldr(TMP, FieldAddress(R1, target::Object::tags_offset()));
__ tst(TMP, Operand(1 << target::UntaggedObject::kCardRememberedBit));
__ b(&remember_card, NOT_ZERO);
} else {
#if defined(DEBUG)
Label ok;
__ ldr(TMP, FieldAddress(R1, target::Object::tags_offset()));
__ tst(TMP, Operand(1 << target::UntaggedObject::kCardRememberedBit));
__ b(&ok, ZERO);
__ Stop("Wrong barrier");
__ Bind(&ok);
#endif
}
{
// Atomically clear kOldAndNotRememberedBit.
Label retry, done;
__ PushList((1 << R2) | (1 << R3) | (1 << R4));
__ AddImmediate(R3, R1, target::Object::tags_offset() - kHeapObjectTag);
// R3: Untagged address of header word (ldrex/strex do not support offsets).
__ Bind(&retry);
__ ldrex(R2, R3);
__ tst(R2, Operand(1 << target::UntaggedObject::kOldAndNotRememberedBit));
__ b(&done, ZERO); // Remembered by another thread.
__ bic(R2, R2,
Operand(1 << target::UntaggedObject::kOldAndNotRememberedBit));
__ strex(R4, R2, R3);
__ cmp(R4, Operand(1));
__ b(&retry, EQ);
// Load the StoreBuffer block out of the thread. Then load top_ out of the
// StoreBufferBlock and add the address to the pointers_.
__ ldr(R4, Address(THR, target::Thread::store_buffer_block_offset()));
__ ldr(R2, Address(R4, target::StoreBufferBlock::top_offset()));
__ add(R3, R4, Operand(R2, LSL, target::kWordSizeLog2));
__ str(R1, Address(R3, target::StoreBufferBlock::pointers_offset()));
// Increment top_ and check for overflow.
// R2: top_.
// R4: StoreBufferBlock.
__ add(R2, R2, Operand(1));
__ str(R2, Address(R4, target::StoreBufferBlock::top_offset()));
__ CompareImmediate(R2, target::StoreBufferBlock::kSize);
__ b(&done, NE);
{
LeafRuntimeScope rt(assembler, /*frame_size=*/0,
/*preserve_registers=*/true);
__ mov(R0, Operand(THR));
rt.Call(kStoreBufferBlockProcessRuntimeEntry, 1);
}
__ Bind(&done);
__ PopList((1 << R2) | (1 << R3) | (1 << R4));
__ Ret();
}
if (cards) {
Label retry;
// Get card table.
__ Bind(&remember_card);
__ AndImmediate(TMP, R1, target::kPageMask); // Page.
__ ldr(TMP,
Address(TMP, target::Page::card_table_offset())); // Card table.
// Atomically dirty the card.
__ PushList((1 << R0) | (1 << R1) | (1 << R2));
__ AndImmediate(TMP, R1, target::kPageMask); // Page.
__ sub(R9, R9, Operand(TMP)); // Offset in page.
__ Lsr(R9, R9, Operand(target::Page::kBytesPerCardLog2)); // Card index.
__ AndImmediate(R1, R9, target::kBitsPerWord - 1); // Lsl is not mod 32.
__ LoadImmediate(R0, 1); // Bit offset.
__ Lsl(R0, R0, R1); // Bit mask.
__ ldr(TMP,
Address(TMP, target::Page::card_table_offset())); // Card table.
__ Lsr(R9, R9, Operand(target::kBitsPerWordLog2)); // Word index.
__ add(TMP, TMP, Operand(R9, LSL, target::kWordSizeLog2)); // Word address.
__ Bind(&retry);
__ ldrex(R1, TMP);
__ orr(R1, R1, Operand(R0));
__ strex(R2, R1, TMP);
__ cmp(R2, Operand(1));
__ b(&retry, EQ);
__ PopList((1 << R0) | (1 << R1) | (1 << R2));
__ Ret();
}
}
void StubCodeCompiler::GenerateWriteBarrierStub() {
GenerateWriteBarrierStubHelper(assembler, false);
}
void StubCodeCompiler::GenerateArrayWriteBarrierStub() {
GenerateWriteBarrierStubHelper(assembler, true);
}
static void GenerateAllocateObjectHelper(Assembler* assembler,
bool is_cls_parameterized) {
const Register kTagsReg = AllocateObjectABI::kTagsReg;
{
Label slow_case;
#if !defined(PRODUCT)
{
const Register kTraceAllocationTempReg = R8;
const Register kCidRegister = R9;
__ ExtractClassIdFromTags(kCidRegister, AllocateObjectABI::kTagsReg);
__ MaybeTraceAllocation(kCidRegister, &slow_case,
kTraceAllocationTempReg);
}
#endif
const Register kNewTopReg = R8;
// Bump allocation.
{
const Register kEndReg = R1;
const Register kInstanceSizeReg = R9;
__ ExtractInstanceSizeFromTags(kInstanceSizeReg, kTagsReg);
// Load two words from Thread::top: top and end.
// AllocateObjectABI::kResultReg: potential next object start.
__ ldrd(AllocateObjectABI::kResultReg, kEndReg, THR,
target::Thread::top_offset());
__ add(kNewTopReg, AllocateObjectABI::kResultReg,
Operand(kInstanceSizeReg));
__ CompareRegisters(kEndReg, kNewTopReg);
__ b(&slow_case, UNSIGNED_LESS_EQUAL);
// Successfully allocated the object, now update top to point to
// next object start and store the class in the class field of object.
__ str(kNewTopReg, Address(THR, target::Thread::top_offset()));
} // kEndReg = R1, kInstanceSizeReg = R9
// Tags.
__ InitializeHeaderUntagged(kTagsReg, AllocateObjectABI::kResultReg);
// Initialize the remaining words of the object.
{
const Register kFieldReg = R1;
const Register kNullReg = R9;
__ LoadObject(kNullReg, NullObject());
__ AddImmediate(kFieldReg, AllocateObjectABI::kResultReg,
target::Instance::first_field_offset());
Label done, init_loop;
__ Bind(&init_loop);
__ CompareRegisters(kFieldReg, kNewTopReg);
__ b(&done, UNSIGNED_GREATER_EQUAL);
__ str(kNullReg,
Address(kFieldReg, target::kWordSize, Address::PostIndex));
__ b(&init_loop);
__ Bind(&done);
} // kFieldReg = R1, kNullReg = R9
__ AddImmediate(AllocateObjectABI::kResultReg,
AllocateObjectABI::kResultReg, kHeapObjectTag);
// Store parameterized type.
if (is_cls_parameterized) {
Label not_parameterized_case;
const Register kClsIdReg = R2;
const Register kTypeOffsetReg = R9;
__ ExtractClassIdFromTags(kClsIdReg, kTagsReg);
// Load class' type_arguments_field offset in words.
__ LoadClassById(kTypeOffsetReg, kClsIdReg);
__ ldr(
kTypeOffsetReg,
FieldAddress(kTypeOffsetReg,
target::Class::
host_type_arguments_field_offset_in_words_offset()));
// Set the type arguments in the new object.
__ add(kTypeOffsetReg, AllocateObjectABI::kResultReg,
Operand(kTypeOffsetReg, LSL, target::kWordSizeLog2));
__ StoreIntoObjectNoBarrier(AllocateObjectABI::kResultReg,
FieldAddress(kTypeOffsetReg, 0),
AllocateObjectABI::kTypeArgumentsReg);
__ Bind(&not_parameterized_case);
} // kClsIdReg = R1, kTypeOffsetReg = R9
__ Ret();
__ Bind(&slow_case);
} // kNewTopReg = R8
// Fall back on slow case:
{
const Register kStubReg = R8;
if (!is_cls_parameterized) {
__ LoadObject(AllocateObjectABI::kTypeArgumentsReg, NullObject());
}
// Tail call to generic allocation stub.
__ ldr(kStubReg,
Address(THR,
target::Thread::allocate_object_slow_entry_point_offset()));
__ bx(kStubReg);
} // kStubReg = R8
}
// Called for inline allocation of objects (any class).
void StubCodeCompiler::GenerateAllocateObjectStub() {
GenerateAllocateObjectHelper(assembler, /*is_cls_parameterized=*/false);
}
void StubCodeCompiler::GenerateAllocateObjectParameterizedStub() {
GenerateAllocateObjectHelper(assembler, /*is_cls_parameterized=*/true);
}
void StubCodeCompiler::GenerateAllocateObjectSlowStub() {
const Register kClsReg = R1;
if (!FLAG_precompiled_mode) {
__ ldr(CODE_REG,
Address(THR, target::Thread::call_to_runtime_stub_offset()));
}
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
__ ExtractClassIdFromTags(AllocateObjectABI::kResultReg,
AllocateObjectABI::kTagsReg);
__ LoadClassById(kClsReg, AllocateObjectABI::kResultReg);
__ LoadObject(AllocateObjectABI::kResultReg, NullObject());
// Pushes result slot, then parameter class and type arguments.
// Type arguments should be Object::null() if class is non-parameterized.
__ PushRegistersInOrder({AllocateObjectABI::kResultReg, kClsReg,
AllocateObjectABI::kTypeArgumentsReg});
__ CallRuntime(kAllocateObjectRuntimeEntry, 2);
// Load result off the stack into result register.
__ ldr(AllocateObjectABI::kResultReg, Address(SP, 2 * target::kWordSize));
// Write-barrier elimination is enabled for [cls] and we therefore need to
// ensure that the object is in new-space or has remembered bit set.
EnsureIsNewOrRemembered();
__ LeaveDartFrameAndReturn();
}
// Called for inline allocation of objects.
void StubCodeCompiler::GenerateAllocationStubForClass(
UnresolvedPcRelativeCalls* unresolved_calls,
const Class& cls,
const Code& allocate_object,
const Code& allocat_object_parametrized) {
classid_t cls_id = target::Class::GetId(cls);
ASSERT(cls_id != kIllegalCid);
// The generated code is different if the class is parameterized.
const bool is_cls_parameterized = target::Class::NumTypeArguments(cls) > 0;
ASSERT(!is_cls_parameterized || target::Class::TypeArgumentsFieldOffset(
cls) != target::Class::kNoTypeArguments);
const intptr_t instance_size = target::Class::GetInstanceSize(cls);
ASSERT(instance_size > 0);
const uword tags =
target::MakeTagWordForNewSpaceObject(cls_id, instance_size);
const Register kTagsReg = AllocateObjectABI::kTagsReg;
__ LoadImmediate(kTagsReg, tags);
if (!FLAG_use_slow_path && FLAG_inline_alloc &&
!target::Class::TraceAllocation(cls) &&
target::SizeFitsInSizeTag(instance_size)) {
RELEASE_ASSERT(AllocateObjectInstr::WillAllocateNewOrRemembered(cls));
RELEASE_ASSERT(target::Heap::IsAllocatableInNewSpace(instance_size));
if (is_cls_parameterized) {
if (!IsSameObject(NullObject(),
CastHandle<Object>(allocat_object_parametrized))) {
__ GenerateUnRelocatedPcRelativeTailCall();
unresolved_calls->Add(new UnresolvedPcRelativeCall(
__ CodeSize(), allocat_object_parametrized, /*is_tail_call=*/true));
} else {
__ ldr(PC,
Address(THR,
target::Thread::
allocate_object_parameterized_entry_point_offset()));
}
} else {
if (!IsSameObject(NullObject(), CastHandle<Object>(allocate_object))) {
__ GenerateUnRelocatedPcRelativeTailCall();
unresolved_calls->Add(new UnresolvedPcRelativeCall(
__ CodeSize(), allocate_object, /*is_tail_call=*/true));
} else {
__ ldr(
PC,
Address(THR, target::Thread::allocate_object_entry_point_offset()));
}
}
} else {
if (!is_cls_parameterized) {
__ LoadObject(AllocateObjectABI::kTypeArgumentsReg, NullObject());
}
__ ldr(PC,
Address(THR,
target::Thread::allocate_object_slow_entry_point_offset()));
}
}
// Called for invoking "dynamic noSuchMethod(Invocation invocation)" function
// from the entry code of a dart function after an error in passed argument
// name or number is detected.
// Input parameters:
// LR : return address.
// SP : address of last argument.
// R4: arguments descriptor array.
void StubCodeCompiler::GenerateCallClosureNoSuchMethodStub() {
__ EnterStubFrame();
// Load the receiver.
__ ldr(R2, FieldAddress(R4, target::ArgumentsDescriptor::count_offset()));
__ add(IP, FP, Operand(R2, LSL, 1)); // R2 is Smi.
__ ldr(R8, Address(IP, target::frame_layout.param_end_from_fp *
target::kWordSize));
// Load the function.
__ ldr(R6, FieldAddress(R8, target::Closure::function_offset()));
// Push space for the return value.
// Push the receiver.
// Push arguments descriptor array.
__ LoadImmediate(IP, 0);
__ PushList((1 << R4) | (1 << R6) | (1 << R8) | (1 << IP));
// Adjust arguments count.
__ ldr(R3,
FieldAddress(R4, target::ArgumentsDescriptor::type_args_len_offset()));
__ cmp(R3, Operand(0));
__ AddImmediate(R2, R2, target::ToRawSmi(1),
NE); // Include the type arguments.
// R2: Smi-tagged arguments array length.
PushArrayOfArguments(assembler);
const intptr_t kNumArgs = 4;
__ CallRuntime(kNoSuchMethodFromPrologueRuntimeEntry, kNumArgs);
// noSuchMethod on closures always throws an error, so it will never return.
__ bkpt(0);
}
// R8: function object.
// R9: inline cache data object.
// Cannot use function object from ICData as it may be the inlined
// function and not the top-scope function.
void StubCodeCompiler::GenerateOptimizedUsageCounterIncrement() {
Register ic_reg = R9;
Register func_reg = R8;
if (FLAG_precompiled_mode) {
__ Breakpoint();
return;
}
if (FLAG_trace_optimized_ic_calls) {
__ EnterStubFrame();
__ PushList((1 << R9) | (1 << R8)); // Preserve.
__ Push(ic_reg); // Argument.
__ Push(func_reg); // Argument.
__ CallRuntime(kTraceICCallRuntimeEntry, 2);
__ Drop(2); // Discard argument;
__ PopList((1 << R9) | (1 << R8)); // Restore.
__ LeaveStubFrame();
}
__ ldr(TMP, FieldAddress(func_reg, target::Function::usage_counter_offset()));
__ add(TMP, TMP, Operand(1));
__ str(TMP, FieldAddress(func_reg, target::Function::usage_counter_offset()));
}
// Loads function into 'temp_reg'.
void StubCodeCompiler::GenerateUsageCounterIncrement(Register temp_reg) {
if (FLAG_precompiled_mode) {
__ Breakpoint();
return;
}
if (FLAG_optimization_counter_threshold >= 0) {
Register func_reg = temp_reg;
ASSERT(temp_reg == R8);
__ Comment("Increment function counter");
__ ldr(func_reg, FieldAddress(IC_DATA_REG, target::ICData::owner_offset()));
__ ldr(TMP,
FieldAddress(func_reg, target::Function::usage_counter_offset()));
__ add(TMP, TMP, Operand(1));
__ str(TMP,
FieldAddress(func_reg, target::Function::usage_counter_offset()));
}
}
// Note: R9 must be preserved.
// Attempt a quick Smi operation for known operations ('kind'). The ICData
// must have been primed with a Smi/Smi check that will be used for counting
// the invocations.
static void EmitFastSmiOp(Assembler* assembler,
Token::Kind kind,
intptr_t num_args,
Label* not_smi_or_overflow) {
__ Comment("Fast Smi op");
__ ldr(R0, Address(SP, 1 * target::kWordSize)); // Left.
__ ldr(R1, Address(SP, 0 * target::kWordSize)); // Right.
__ orr(TMP, R0, Operand(R1));
__ tst(TMP, Operand(kSmiTagMask));
__ b(not_smi_or_overflow, NE);
switch (kind) {
case Token::kADD: {
__ adds(R0, R1, Operand(R0)); // Adds.
__ b(not_smi_or_overflow, VS); // Branch if overflow.
break;
}
case Token::kLT: {
__ cmp(R0, Operand(R1));
__ LoadObject(R0, CastHandle<Object>(TrueObject()), LT);
__ LoadObject(R0, CastHandle<Object>(FalseObject()), GE);
break;
}
case Token::kEQ: {
__ cmp(R0, Operand(R1));
__ LoadObject(R0, CastHandle<Object>(TrueObject()), EQ);
__ LoadObject(R0, CastHandle<Object>(FalseObject()), NE);
break;
}
default:
UNIMPLEMENTED();
}
// R9: IC data object (preserved).
__ ldr(R8, FieldAddress(R9, target::ICData::entries_offset()));
// R8: ic_data_array with check entries: classes and target functions.
__ AddImmediate(R8, target::Array::data_offset() - kHeapObjectTag);
// R8: points directly to the first ic data array element.
#if defined(DEBUG)
// Check that first entry is for Smi/Smi.
Label error, ok;
const intptr_t imm_smi_cid = target::ToRawSmi(kSmiCid);
__ ldr(R1, Address(R8, 0));
__ CompareImmediate(R1, imm_smi_cid);
__ b(&error, NE);
__ ldr(R1, Address(R8, target::kWordSize));
__ CompareImmediate(R1, imm_smi_cid);
__ b(&ok, EQ);
__ Bind(&error);
__ Stop("Incorrect IC data");
__ Bind(&ok);
#endif
if (FLAG_optimization_counter_threshold >= 0) {
// Update counter, ignore overflow.
const intptr_t count_offset =
target::ICData::CountIndexFor(num_args) * target::kWordSize;
__ LoadFromOffset(R1, R8, count_offset);
__ adds(R1, R1, Operand(target::ToRawSmi(1)));
__ StoreIntoSmiField(Address(R8, count_offset), R1);
}
__ Ret();
}
// Saves the offset of the target entry-point (from the Function) into R3.
//
// Must be the first code generated, since any code before will be skipped in
// the unchecked entry-point.
static void GenerateRecordEntryPoint(Assembler* assembler) {
Label done;
__ mov(R3, Operand(target::Function::entry_point_offset() - kHeapObjectTag));
__ b(&done);
__ BindUncheckedEntryPoint();
__ mov(
R3,
Operand(target::Function::entry_point_offset(CodeEntryKind::kUnchecked) -
kHeapObjectTag));
__ Bind(&done);
}
// Generate inline cache check for 'num_args'.
// R0: receiver (if instance call)
// R9: ICData
// LR: return address
// Control flow:
// - If receiver is null -> jump to IC miss.
// - If receiver is Smi -> load Smi class.
// - If receiver is not-Smi -> load receiver's class.
// - Check if 'num_args' (including receiver) match any IC data group.
// - Match found -> jump to target.
// - Match not found -> jump to IC miss.
void StubCodeCompiler::GenerateNArgsCheckInlineCacheStub(
intptr_t num_args,
const RuntimeEntry& handle_ic_miss,
Token::Kind kind,
Optimized optimized,
CallType type,
Exactness exactness) {
if (FLAG_precompiled_mode) {
__ Breakpoint();
return;
}
const bool save_entry_point = kind == Token::kILLEGAL;
if (save_entry_point) {
GenerateRecordEntryPoint(assembler);
}
if (optimized == kOptimized) {
GenerateOptimizedUsageCounterIncrement();
} else {
GenerateUsageCounterIncrement(/* scratch */ R8);
}
__ CheckCodePointer();
ASSERT(num_args == 1 || num_args == 2);
#if defined(DEBUG)
{
Label ok;
// Check that the IC data array has NumArgsTested() == num_args.
// 'NumArgsTested' is stored in the least significant bits of 'state_bits'.
__ ldr(R8, FieldAddress(R9, target::ICData::state_bits_offset()));
ASSERT(target::ICData::NumArgsTestedShift() == 0); // No shift needed.
__ and_(R8, R8, Operand(target::ICData::NumArgsTestedMask()));
__ CompareImmediate(R8, num_args);
__ b(&ok, EQ);
__ Stop("Incorrect stub for IC data");
__ Bind(&ok);
}
#endif // DEBUG
#if !defined(PRODUCT)
Label stepping, done_stepping;
if (optimized == kUnoptimized) {
__ Comment("Check single stepping");
__ LoadIsolate(R8);
__ ldrb(R8, Address(R8, target::Isolate::single_step_offset()));
__ CompareImmediate(R8, 0);
__ b(&stepping, NE);
__ Bind(&done_stepping);
}
#endif
Label not_smi_or_overflow;
if (kind != Token::kILLEGAL) {
EmitFastSmiOp(assembler, kind, num_args, &not_smi_or_overflow);
}
__ Bind(&not_smi_or_overflow);
__ Comment("Extract ICData initial values and receiver cid");
// R9: IC data object (preserved).
__ ldr(R8, FieldAddress(R9, target::ICData::entries_offset()));
// R8: ic_data_array with check entries: classes and target functions.
const int kIcDataOffset = target::Array::data_offset() - kHeapObjectTag;
// R8: points at the IC data array.
if (type == kInstanceCall) {
__ LoadTaggedClassIdMayBeSmi(NOTFP, R0);
__ ldr(
ARGS_DESC_REG,
FieldAddress(R9, target::CallSiteData::arguments_descriptor_offset()));
if (num_args == 2) {
__ ldr(R1, FieldAddress(ARGS_DESC_REG,
target::ArgumentsDescriptor::count_offset()));
__ sub(R1, R1, Operand(target::ToRawSmi(2)));
__ ldr(R1, Address(SP, R1, LSL, 1)); // R1 (argument_count - 2) is Smi.
__ LoadTaggedClassIdMayBeSmi(R1, R1);
}
} else {
// Load arguments descriptor into R4.
__ ldr(
ARGS_DESC_REG,
FieldAddress(R9, target::CallSiteData::arguments_descriptor_offset()));
// Get the receiver's class ID (first read number of arguments from
// arguments descriptor array and then access the receiver from the stack).
__ ldr(R1, FieldAddress(ARGS_DESC_REG,
target::ArgumentsDescriptor::count_offset()));
__ sub(R1, R1, Operand(target::ToRawSmi(1)));
// R1: argument_count - 1 (smi).
__ ldr(R0, Address(SP, R1, LSL, 1)); // R1 (argument_count - 1) is Smi.
__ LoadTaggedClassIdMayBeSmi(NOTFP, R0);
if (num_args == 2) {
__ sub(R1, R1, Operand(target::ToRawSmi(1)));
__ ldr(R1, Address(SP, R1, LSL, 1)); // R1 (argument_count - 2) is Smi.
__ LoadTaggedClassIdMayBeSmi(R1, R1);
}
}
// NOTFP: first argument class ID as Smi.
// R1: second argument class ID as Smi.
// R4: args descriptor
// Loop that checks if there is an IC data match.
Label loop, found, miss;
__ Comment("ICData loop");
// We unroll the generic one that is generated once more than the others.
const bool optimize = kind == Token::kILLEGAL;
__ Bind(&loop);
for (int unroll = optimize ? 4 : 2; unroll >= 0; unroll--) {
Label update;
__ ldr(R2, Address(R8, kIcDataOffset));
__ cmp(NOTFP, Operand(R2)); // Class id match?
if (num_args == 2) {
__ b(&update, NE); // Continue.
__ ldr(R2, Address(R8, kIcDataOffset + target::kWordSize));
__ cmp(R1, Operand(R2)); // Class id match?
}
__ b(&found, EQ); // Break.
__ Bind(&update);
const intptr_t entry_size = target::ICData::TestEntryLengthFor(
num_args, exactness == kCheckExactness) *
target::kWordSize;
__ AddImmediate(R8, entry_size); // Next entry.
__ CompareImmediate(R2, target::ToRawSmi(kIllegalCid)); // Done?
if (unroll == 0) {
__ b(&loop, NE);
} else {
__ b(&miss, EQ);
}
}
__ Bind(&miss);
__ Comment("IC miss");
// Compute address of arguments.
__ ldr(R1, FieldAddress(ARGS_DESC_REG,
target::ArgumentsDescriptor::count_offset()));
__ sub(R1, R1, Operand(target::ToRawSmi(1)));
// R1: argument_count - 1 (smi).
__ add(R1, SP, Operand(R1, LSL, 1)); // R1 is Smi.
// R1: address of receiver.
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
__ LoadImmediate(R0, 0);
// Preserve IC data object and arguments descriptor array and
// setup space on stack for result (target code object).
RegList regs = (1 << R0) | (1 << ARGS_DESC_REG) | (1 << R9);
if (save_entry_point) {
__ SmiTag(R3);
regs |= 1 << R3;
}
__ PushList(regs);
// Push call arguments.
for (intptr_t i = 0; i < num_args; i++) {
__ LoadFromOffset(TMP, R1, -i * target::kWordSize);
__ Push(TMP);
}
// Pass IC data object.
__ Push(R9);
__ CallRuntime(handle_ic_miss, num_args + 1);
// Remove the call arguments pushed earlier, including the IC data object.
__ Drop(num_args + 1);
// Pop returned function object into R0.
// Restore arguments descriptor array and IC data array.
COMPILE_ASSERT(FUNCTION_REG == R0);
__ PopList(regs);
if (save_entry_point) {
__ SmiUntag(R3);
}
__ RestoreCodePointer();
__ LeaveStubFrame();
Label call_target_function;
if (FLAG_precompiled_mode) {
GenerateDispatcherCode(assembler, &call_target_function);
} else {
__ b(&call_target_function);
}
__ Bind(&found);
// R8: pointer to an IC data check group.
const intptr_t target_offset =
target::ICData::TargetIndexFor(num_args) * target::kWordSize;
const intptr_t count_offset =
target::ICData::CountIndexFor(num_args) * target::kWordSize;
const intptr_t exactness_offset =
target::ICData::ExactnessIndexFor(num_args) * target::kWordSize;
Label call_target_function_through_unchecked_entry;
if (exactness == kCheckExactness) {
Label exactness_ok;
ASSERT(num_args == 1);
__ ldr(R1, Address(R8, kIcDataOffset + exactness_offset));
__ CompareImmediate(
R1, target::ToRawSmi(
StaticTypeExactnessState::HasExactSuperType().Encode()));
__ BranchIf(LESS, &exactness_ok);
__ BranchIf(EQUAL, &call_target_function_through_unchecked_entry);
// Check trivial exactness.
// Note: UntaggedICData::receivers_static_type_ is guaranteed to be not null
// because we only emit calls to this stub when it is not null.
__ ldr(R2,
FieldAddress(R9, target::ICData::receivers_static_type_offset()));
__ ldr(R2, FieldAddress(R2, target::Type::arguments_offset()));
// R1 contains an offset to type arguments in words as a smi,
// hence TIMES_2. R0 is guaranteed to be non-smi because it is expected
// to have type argument.
__ LoadIndexedPayload(TMP, R0, 0, R1, TIMES_2);
__ CompareObjectRegisters(R2, TMP);
__ BranchIf(EQUAL, &call_target_function_through_unchecked_entry);
// Update exactness state (not-exact anymore).
__ LoadImmediate(
R1, target::ToRawSmi(StaticTypeExactnessState::NotExact().Encode()));
__ str(R1, Address(R8, kIcDataOffset + exactness_offset));
__ Bind(&exactness_ok);
}
__ LoadFromOffset(FUNCTION_REG, R8, kIcDataOffset + target_offset);
if (FLAG_optimization_counter_threshold >= 0) {
__ Comment("Update caller's counter");
__ LoadFromOffset(R1, R8, kIcDataOffset + count_offset);
__ add(R1, R1, Operand(target::ToRawSmi(1))); // Ignore overflow.
__ StoreIntoSmiField(Address(R8, kIcDataOffset + count_offset), R1);
}
__ Comment("Call target");
__ Bind(&call_target_function);
// R0: target function.
__ ldr(CODE_REG, FieldAddress(FUNCTION_REG, target::Function::code_offset()));
if (save_entry_point) {
__ Branch(Address(FUNCTION_REG, R3));
} else {
__ Branch(
FieldAddress(FUNCTION_REG, target::Function::entry_point_offset()));
}
if (exactness == kCheckExactness) {
__ Bind(&call_target_function_through_unchecked_entry);
if (FLAG_optimization_counter_threshold >= 0) {
__ Comment("Update ICData counter");
__ LoadFromOffset(R1, R8, kIcDataOffset + count_offset);
__ add(R1, R1, Operand(target::ToRawSmi(1))); // Ignore overflow.
__ StoreIntoSmiField(Address(R8, kIcDataOffset + count_offset), R1);
}
__ Comment("Call target (via unchecked entry point)");
__ LoadFromOffset(FUNCTION_REG, R8, kIcDataOffset + target_offset);
__ ldr(CODE_REG,
FieldAddress(FUNCTION_REG, target::Function::code_offset()));
__ Branch(FieldAddress(FUNCTION_REG, target::Function::entry_point_offset(
CodeEntryKind::kUnchecked)));
}
#if !defined(PRODUCT)
if (optimized == kUnoptimized) {
__ Bind(&stepping);
__ EnterStubFrame();
if (type == kInstanceCall) {
__ Push(R0); // Preserve receiver.
}
RegList regs = 1 << R9;
if (save_entry_point) {
regs |= 1 << R3;
__ SmiTag(R3); // Entry-point is not Smi.
}
__ PushList(regs); // Preserve IC data and entry-point.
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ PopList(regs); // Restore IC data and entry-point
if (save_entry_point) {
__ SmiUntag(R3);
}
if (type == kInstanceCall) {
__ Pop(R0);
}
__ RestoreCodePointer();
__ LeaveStubFrame();
__ b(&done_stepping);
}
#endif
}
// R0: receiver
// R9: ICData
// LR: return address
void StubCodeCompiler::GenerateOneArgCheckInlineCacheStub() {
GenerateNArgsCheckInlineCacheStub(
1, kInlineCacheMissHandlerOneArgRuntimeEntry, Token::kILLEGAL,
kUnoptimized, kInstanceCall, kIgnoreExactness);
}
// R0: receiver
// R9: ICData
// LR: return address
void StubCodeCompiler::GenerateOneArgCheckInlineCacheWithExactnessCheckStub() {
GenerateNArgsCheckInlineCacheStub(
1, kInlineCacheMissHandlerOneArgRuntimeEntry, Token::kILLEGAL,
kUnoptimized, kInstanceCall, kCheckExactness);
}
// R0: receiver
// R9: ICData
// LR: return address
void StubCodeCompiler::GenerateTwoArgsCheckInlineCacheStub() {
GenerateNArgsCheckInlineCacheStub(
2, kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kILLEGAL,
kUnoptimized, kInstanceCall, kIgnoreExactness);
}
// R0: receiver
// R9: ICData
// LR: return address
void StubCodeCompiler::GenerateSmiAddInlineCacheStub() {
GenerateNArgsCheckInlineCacheStub(
2, kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kADD, kUnoptimized,
kInstanceCall, kIgnoreExactness);
}
// R0: receiver
// R9: ICData
// LR: return address
void StubCodeCompiler::GenerateSmiLessInlineCacheStub() {
GenerateNArgsCheckInlineCacheStub(
2, kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kLT, kUnoptimized,
kInstanceCall, kIgnoreExactness);
}
// R0: receiver
// R9: ICData
// LR: return address
void StubCodeCompiler::GenerateSmiEqualInlineCacheStub() {
GenerateNArgsCheckInlineCacheStub(
2, kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kEQ, kUnoptimized,
kInstanceCall, kIgnoreExactness);
}
// R0: receiver
// R9: ICData
// R8: Function
// LR: return address
void StubCodeCompiler::GenerateOneArgOptimizedCheckInlineCacheStub() {
GenerateNArgsCheckInlineCacheStub(
1, kInlineCacheMissHandlerOneArgRuntimeEntry, Token::kILLEGAL, kOptimized,
kInstanceCall, kIgnoreExactness);
}
// R0: receiver
// R9: ICData
// R8: Function
// LR: return address
void StubCodeCompiler::
GenerateOneArgOptimizedCheckInlineCacheWithExactnessCheckStub() {
GenerateNArgsCheckInlineCacheStub(
1, kInlineCacheMissHandlerOneArgRuntimeEntry, Token::kILLEGAL, kOptimized,
kInstanceCall, kCheckExactness);
}
// R0: receiver
// R9: ICData
// R8: Function
// LR: return address
void StubCodeCompiler::GenerateTwoArgsOptimizedCheckInlineCacheStub() {
GenerateNArgsCheckInlineCacheStub(
2, kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kILLEGAL,
kOptimized, kInstanceCall, kIgnoreExactness);
}
// R9: ICData
// LR: return address
void StubCodeCompiler::GenerateZeroArgsUnoptimizedStaticCallStub() {
GenerateRecordEntryPoint(assembler);
GenerateUsageCounterIncrement(/* scratch */ R8);
#if defined(DEBUG)
{
Label ok;
// Check that the IC data array has NumArgsTested() == 0.
// 'NumArgsTested' is stored in the least significant bits of 'state_bits'.
__ ldr(R8, FieldAddress(R9, target::ICData::state_bits_offset()));
ASSERT(target::ICData::NumArgsTestedShift() == 0); // No shift needed.
__ and_(R8, R8, Operand(target::ICData::NumArgsTestedMask()));
__ CompareImmediate(R8, 0);
__ b(&ok, EQ);
__ Stop("Incorrect IC data for unoptimized static call");
__ Bind(&ok);
}
#endif // DEBUG
#if !defined(PRODUCT)
// Check single stepping.
Label stepping, done_stepping;
__ LoadIsolate(R8);
__ ldrb(R8, Address(R8, target::Isolate::single_step_offset()));
__ CompareImmediate(R8, 0);
__ b(&stepping, NE);
__ Bind(&done_stepping);
#endif
// R9: IC data object (preserved).
__ ldr(R8, FieldAddress(R9, target::ICData::entries_offset()));
// R8: ic_data_array with entries: target functions and count.
__ AddImmediate(R8, target::Array::data_offset() - kHeapObjectTag);
// R8: points directly to the first ic data array element.
const intptr_t target_offset =
target::ICData::TargetIndexFor(0) * target::kWordSize;
const intptr_t count_offset =
target::ICData::CountIndexFor(0) * target::kWordSize;
if (FLAG_optimization_counter_threshold >= 0) {
// Increment count for this call, ignore overflow.
__ LoadFromOffset(R1, R8, count_offset);
__ adds(R1, R1, Operand(target::ToRawSmi(1)));
__ StoreIntoSmiField(Address(R8, count_offset), R1);
}
// Load arguments descriptor into R4.
__ ldr(ARGS_DESC_REG,
FieldAddress(R9, target::CallSiteData::arguments_descriptor_offset()));
// Get function and call it, if possible.
__ LoadFromOffset(FUNCTION_REG, R8, target_offset);
__ ldr(CODE_REG, FieldAddress(FUNCTION_REG, target::Function::code_offset()));
__ Branch(Address(FUNCTION_REG, R3));
#if !defined(PRODUCT)
__ Bind(&stepping);
__ EnterStubFrame();
__ SmiTag(R3); // Entry-point is not Smi.
__ PushList((1 << R9) | (1 << R3)); // Preserve IC data and entry-point.
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ PopList((1 << R9) | (1 << R3));
__ SmiUntag(R3);
__ RestoreCodePointer();
__ LeaveStubFrame();
__ b(&done_stepping);
#endif
}
// R9: ICData
// LR: return address
void StubCodeCompiler::GenerateOneArgUnoptimizedStaticCallStub() {
GenerateUsageCounterIncrement(/* scratch */ R8);
GenerateNArgsCheckInlineCacheStub(1, kStaticCallMissHandlerOneArgRuntimeEntry,
Token::kILLEGAL, kUnoptimized, kStaticCall,
kIgnoreExactness);
}
// R9: ICData
// LR: return address
void StubCodeCompiler::GenerateTwoArgsUnoptimizedStaticCallStub() {
GenerateUsageCounterIncrement(/* scratch */ R8);
GenerateNArgsCheckInlineCacheStub(
2, kStaticCallMissHandlerTwoArgsRuntimeEntry, Token::kILLEGAL,
kUnoptimized, kStaticCall, kIgnoreExactness);
}
// Stub for compiling a function and jumping to the compiled code.
// ARGS_DESC_REG: Arguments descriptor.
// FUNCTION_REG: Function.
void StubCodeCompiler::GenerateLazyCompileStub() {
__ EnterStubFrame();
// Preserve arg desc, pass function.
COMPILE_ASSERT(FUNCTION_REG < ARGS_DESC_REG);
__ PushList((1 << FUNCTION_REG) | (1 << ARGS_DESC_REG));
__ CallRuntime(kCompileFunctionRuntimeEntry, 1);
__ PopList((1 << FUNCTION_REG) | (1 << ARGS_DESC_REG));
__ LeaveStubFrame();
__ ldr(CODE_REG, FieldAddress(FUNCTION_REG, target::Function::code_offset()));
__ Branch(FieldAddress(FUNCTION_REG, target::Function::entry_point_offset()));
}
// Stub for interpreting a function call.
// R4: Arguments descriptor.
// R0: Function.
void StubCodeCompiler::GenerateInterpretCallStub() {
#if defined(DART_DYNAMIC_MODULES)
__ EnterStubFrame();
#if defined(DEBUG)
{
Label ok;
// Check that we are always entering from Dart code.
__ LoadFromOffset(R8, THR, target::Thread::vm_tag_offset());
__ CompareImmediate(R8, VMTag::kDartTagId);
__ b(&ok, EQ);
__ Stop("Not coming from Dart code.");
__ Bind(&ok);
}
#endif
// Adjust arguments count for type arguments vector.
__ LoadFieldFromOffset(R2, R4, target::ArgumentsDescriptor::count_offset());
__ SmiUntag(R2);
__ LoadFieldFromOffset(R1, R4,
target::ArgumentsDescriptor::type_args_len_offset());
__ cmp(R1, Operand(0));
__ AddImmediate(R2, R2, 1, NE); // Include the type arguments.
// Compute argv.
__ mov(R3, Operand(R2, LSL, 2));
__ add(R3, FP, Operand(R3));
__ AddImmediate(R3,
target::frame_layout.param_end_from_fp * target::kWordSize);
// Indicate decreasing memory addresses of arguments with negative argc.
__ rsb(R2, R2, Operand(0));
// Align frame before entering C++ world. Fifth argument passed on the stack.
__ ReserveAlignedFrameSpace(1 * target::kWordSize);
// Pass arguments in registers.
// R0: Function.
__ mov(R1, Operand(R4)); // Arguments descriptor.
// R2: Negative argc.
// R3: Argv.
__ str(THR, Address(SP, 0)); // Fifth argument: Thread.
// Save exit frame information to enable stack walking as we are about
// to transition to Dart VM C++ code.
__ StoreToOffset(FP, THR, target::Thread::top_exit_frame_info_offset());
// Mark that the thread exited generated code through a runtime call.
__ LoadImmediate(R5, target::Thread::exit_through_runtime_call());
__ StoreToOffset(R5, THR, target::Thread::exit_through_ffi_offset());
// Mark that the thread is executing VM code.
__ LoadFromOffset(R5, THR,
target::Thread::interpret_call_entry_point_offset());
__ StoreToOffset(R5, THR, target::Thread::vm_tag_offset());
__ blx(R5);
// Mark that the thread is executing Dart code.
__ LoadImmediate(R2, VMTag::kDartTagId);
__ StoreToOffset(R2, THR, target::Thread::vm_tag_offset());
// Mark that the thread has not exited generated Dart code.
__ LoadImmediate(R2, 0);
__ StoreToOffset(R2, THR, target::Thread::exit_through_ffi_offset());
// Reset exit frame information in Isolate's mutator thread structure.
__ StoreToOffset(R2, THR, target::Thread::top_exit_frame_info_offset());
__ LeaveStubFrame();
__ Ret();
#else
__ Stop("Not using Dart dynamic modules");
#endif // defined(DART_DYNAMIC_MODULES)
}
// R9: Contains an ICData.
void StubCodeCompiler::GenerateICCallBreakpointStub() {
#if defined(PRODUCT)
__ Stop("No debugging in PRODUCT mode");
#else
__ EnterStubFrame();
__ Push(R0); // Preserve receiver.
__ Push(R9); // Preserve IC data.
__ PushImmediate(0); // Space for result.
__ CallRuntime(kBreakpointRuntimeHandlerRuntimeEntry, 0);
__ Pop(CODE_REG); // Original stub.
__ Pop(R9); // Restore IC data.
__ Pop(R0); // Restore receiver.
__ LeaveStubFrame();
__ Branch(FieldAddress(CODE_REG, target::Code::entry_point_offset()));
#endif // defined(PRODUCT)
}
void StubCodeCompiler::GenerateUnoptStaticCallBreakpointStub() {
#if defined(PRODUCT)
__ Stop("No debugging in PRODUCT mode");
#else
__ EnterStubFrame();
__ Push(R9); // Preserve IC data.
__ PushImmediate(0); // Space for result.
__ CallRuntime(kBreakpointRuntimeHandlerRuntimeEntry, 0);
__ Pop(CODE_REG); // Original stub.
__ Pop(R9); // Restore IC data.
__ LeaveStubFrame();
__ Branch(FieldAddress(CODE_REG, target::Code::entry_point_offset()));
#endif // defined(PRODUCT)
}
void StubCodeCompiler::GenerateRuntimeCallBreakpointStub() {
#if defined(PRODUCT)
__ Stop("No debugging in PRODUCT mode");
#else
__ EnterStubFrame();
__ LoadImmediate(R0, 0);
// Make room for result.
__ PushList((1 << R0));
__ CallRuntime(kBreakpointRuntimeHandlerRuntimeEntry, 0);
__ PopList((1 << CODE_REG));
__ LeaveStubFrame();
__ Branch(FieldAddress(CODE_REG, target::Code::entry_point_offset()));
#endif // defined(PRODUCT)
}
// Called only from unoptimized code. All relevant registers have been saved.
void StubCodeCompiler::GenerateDebugStepCheckStub() {
#if defined(PRODUCT)
__ Stop("No debugging in PRODUCT mode");
#else
// Check single stepping.
Label stepping, done_stepping;
__ LoadIsolate(R1);
__ ldrb(R1, Address(R1, target::Isolate::single_step_offset()));
__ CompareImmediate(R1, 0);
__ b(&stepping, NE);
__ Bind(&done_stepping);
__ Ret();
__ Bind(&stepping);
__ EnterStubFrame();
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ LeaveStubFrame();
__ b(&done_stepping);
#endif // defined(PRODUCT)
}
// Used to check class and type arguments. Arguments passed in registers:
//
// Inputs (all preserved, mostly from TypeTestABI struct):
// - kSubtypeTestCacheReg: SubtypeTestCacheLayout
// - kInstanceReg: instance to test against.
// - kDstTypeReg: destination type (for n>=7).
// - kInstantiatorTypeArgumentsReg: instantiator type arguments (for n>=3).
// - kFunctionTypeArgumentsReg: function type arguments (for n>=4).
// - LR: return address.
//
// Outputs (from TypeTestABI struct):
// - kSubtypeTestCacheResultReg: the cached result, or null if not found.
void StubCodeCompiler::GenerateSubtypeNTestCacheStub(Assembler* assembler,
int n) {
ASSERT(n >= 1);
ASSERT(n <= SubtypeTestCache::kMaxInputs);
// If we need the parent function type arguments for a closure, we also need
// the delayed type arguments, so this case will never happen.
ASSERT(n != 5);
RegisterSet saved_registers;
// Safe as the original value of TypeTestABI::kSubtypeTestCacheReg is only
// used to initialize this register.
const Register kCacheArrayReg = TypeTestABI::kSubtypeTestCacheReg;
saved_registers.AddRegister(kCacheArrayReg);
// CODE_REG is used only in JIT mode, and the dispatch table only exists in
// AOT mode, so we can use the corresponding register for the mode we're not
// in without having to preserve it.
const Register kNullReg =
FLAG_precompiled_mode ? CODE_REG : DISPATCH_TABLE_REG;
__ LoadObject(kNullReg, NullObject());
// Free up additional registers needed for checks in the loop. Initially
// define them as kNoRegister so any unexpected uses are caught.
Register kInstanceInstantiatorTypeArgumentsReg = kNoRegister;
if (n >= 2) {
kInstanceInstantiatorTypeArgumentsReg = PP;
saved_registers.AddRegister(kInstanceInstantiatorTypeArgumentsReg);
}
Register kInstanceParentFunctionTypeArgumentsReg = kNoRegister;
if (n >= 5) {
// For this, we look at the pair of Registers we considered for kNullReg
// and use the one that must be preserved instead.
kInstanceParentFunctionTypeArgumentsReg =
FLAG_precompiled_mode ? DISPATCH_TABLE_REG : CODE_REG;
saved_registers.AddRegister(kInstanceParentFunctionTypeArgumentsReg);
}
Register kInstanceDelayedFunctionTypeArgumentsReg = kNoRegister;
if (n >= 6) {
// We retrieve all the needed fields from the instance during loop
// initialization and store them in registers, so we don't need the value
// of kInstanceReg during the loop and just need to save and restore it.
// Thus, use kInstanceReg for the last field that can possibly be retrieved
// from the instance.
kInstanceDelayedFunctionTypeArgumentsReg = TypeTestABI::kInstanceReg;
saved_registers.AddRegister(kInstanceDelayedFunctionTypeArgumentsReg);
}
// We'll replace these with actual registers if possible, but fall back to
// the stack if register pressure is too great. The last two values are
// used in every loop iteration, and so are more important to put in
// registers if possible, whereas the first is used only when we go off
// the end of the backing array (usually at most once per check).
Register kCacheContentsSizeReg = kNoRegister;
if (n < 5) {
// Use the register we would have used for the parent function type args.
kCacheContentsSizeReg =
FLAG_precompiled_mode ? DISPATCH_TABLE_REG : CODE_REG;
saved_registers.AddRegister(kCacheContentsSizeReg);
}
Register kProbeDistanceReg = kNoRegister;
if (n < 6) {
// Use the register we would have used for the delayed type args.
kProbeDistanceReg = TypeTestABI::kInstanceReg;
saved_registers.AddRegister(kProbeDistanceReg);
}
Register kCacheEntryEndReg = kNoRegister;
if (n < 7) {
// Use the destination type, as that is the last input that might be unused.
kCacheEntryEndReg = TypeTestABI::kDstTypeReg;
saved_registers.AddRegister(TypeTestABI::kDstTypeReg);
}
__ PushRegisters(saved_registers);
Label not_found;
GenerateSubtypeTestCacheSearch(
assembler, n, kNullReg, kCacheArrayReg,
STCInternalRegs::kInstanceCidOrSignatureReg,
kInstanceInstantiatorTypeArgumentsReg,
kInstanceParentFunctionTypeArgumentsReg,
kInstanceDelayedFunctionTypeArgumentsReg, kCacheEntryEndReg,
kCacheContentsSizeReg, kProbeDistanceReg,
[&](Assembler* assembler, int n) {
__ LoadCompressed(
TypeTestABI::kSubtypeTestCacheResultReg,
Address(kCacheArrayReg, target::kCompressedWordSize *
target::SubtypeTestCache::kTestResult));
__ PopRegisters(saved_registers);
__ Ret();
},
[&](Assembler* assembler, int n) {
__ MoveRegister(TypeTestABI::kSubtypeTestCacheResultReg, kNullReg);
__ PopRegisters(saved_registers);
__ Ret();
});
}
// Return the current stack pointer address, used to do stack alignment checks.
void StubCodeCompiler::GenerateGetCStackPointerStub() {
__ mov(R0, Operand(SP));
__ Ret();
}
// Jump to a frame on the call stack.
// LR: return address.
// R0: program_counter.
// R1: stack_pointer.
// R2: frame_pointer.
// R3: thread.
// Does not return.
//
// Notice: We need to keep this in sync with `Simulator::JumpToFrame()`.
void StubCodeCompiler::GenerateJumpToFrameStub() {
COMPILE_ASSERT(kExceptionObjectReg == R0);
COMPILE_ASSERT(kStackTraceObjectReg == R1);
COMPILE_ASSERT(IsAbiPreservedRegister(R4));
COMPILE_ASSERT(IsAbiPreservedRegister(THR));
__ mov(IP, Operand(R1)); // Copy Stack pointer into IP.
// TransitionGeneratedToNative might clobber LR if it takes the slow path.
__ mov(R4, Operand(R0)); // Program counter.
__ mov(THR, Operand(R3)); // Thread.
__ mov(FP, Operand(R2)); // Frame_pointer.
__ mov(SP, Operand(IP)); // Set Stack pointer.
#if defined(USING_SHADOW_CALL_STACK)
#error Unimplemented
#endif
Label exit_through_non_ffi;
Register tmp1 = R0, tmp2 = R1;
// Check if we exited generated from FFI. If so do transition - this is needed
// because normally runtime calls transition back to generated via destructor
// of TransitionGeneratedToVM/Native that is part of runtime boilerplate
// code (see DEFINE_RUNTIME_ENTRY_IMPL in runtime_entry.h). Ffi calls don't
// have this boilerplate, don't have this stack resource, have to transition
// explicitly.
__ LoadFromOffset(tmp1, THR,
compiler::target::Thread::exit_through_ffi_offset());
__ LoadImmediate(tmp2, target::Thread::exit_through_ffi());
__ cmp(tmp1, Operand(tmp2));
__ b(&exit_through_non_ffi, NE);
__ TransitionNativeToGenerated(tmp1, tmp2,
/*exit_safepoint=*/true,
/*ignore_unwind_in_progress=*/true);
__ Bind(&exit_through_non_ffi);
// Set the tag.
__ LoadImmediate(R2, VMTag::kDartTagId);
__ StoreToOffset(R2, THR, target::Thread::vm_tag_offset());
// Clear top exit frame.
__ LoadImmediate(R2, 0);
__ StoreToOffset(R2, THR, target::Thread::top_exit_frame_info_offset());
// Restore the pool pointer.
__ RestoreCodePointer();
if (FLAG_precompiled_mode) {
__ SetupGlobalPoolAndDispatchTable();
__ set_constant_pool_allowed(true);
} else {
__ LoadPoolPointer();
}
__ bx(R4); // Jump to continuation point.
}
// Run an exception handler. Execution comes from JumpToFrame
// stub or from the simulator.
//
// The arguments are stored in the Thread object.
// Does not return.
static void GenerateRunExceptionHandler(Assembler* assembler,
bool unbox_exception) {
WRITES_RETURN_ADDRESS_TO_LR(
__ LoadFromOffset(LR, THR, target::Thread::resume_pc_offset()));
word offset_from_thread = 0;
bool ok = target::CanLoadFromThread(NullObject(), &offset_from_thread);
ASSERT(ok);
__ LoadFromOffset(R2, THR, offset_from_thread);
// Exception object.
__ LoadFromOffset(R0, THR, target::Thread::active_exception_offset());
__ StoreToOffset(R2, THR, target::Thread::active_exception_offset());
if (unbox_exception) {
compiler::Label not_smi, done;
__ BranchIfNotSmi(R0, &not_smi);
__ SmiUntag(R0);
__ Jump(&done);
__ Bind(&not_smi);
__ ldr(R0, FieldAddress(R0, Mint::value_offset()));
__ Bind(&done);
}
// StackTrace object.
__ LoadFromOffset(R1, THR, target::Thread::active_stacktrace_offset());
__ StoreToOffset(R2, THR, target::Thread::active_stacktrace_offset());
READS_RETURN_ADDRESS_FROM_LR(
__ bx(LR)); // Jump to the exception handler code.
}
void StubCodeCompiler::GenerateRunExceptionHandlerStub() {
GenerateRunExceptionHandler(assembler, false);
}
void StubCodeCompiler::GenerateRunExceptionHandlerUnboxStub() {
GenerateRunExceptionHandler(assembler, true);
}
// Deoptimize a frame on the call stack before rewinding.
// The arguments are stored in the Thread object.
// No result.
void StubCodeCompiler::GenerateDeoptForRewindStub() {
// Push zap value instead of CODE_REG.
__ LoadImmediate(IP, kZapCodeReg);
__ Push(IP);
// Load the deopt pc into LR.
WRITES_RETURN_ADDRESS_TO_LR(
__ LoadFromOffset(LR, THR, target::Thread::resume_pc_offset()));
GenerateDeoptimizationSequence(assembler, kEagerDeopt);
// After we have deoptimized, jump to the correct frame.
__ EnterStubFrame();
__ CallRuntime(kRewindPostDeoptRuntimeEntry, 0);
__ LeaveStubFrame();
__ bkpt(0);
}
// Calls to the runtime to optimize the given function.
// R8: function to be reoptimized.
// ARGS_DESC_REG: argument descriptor (preserved).
void StubCodeCompiler::GenerateOptimizeFunctionStub() {
__ ldr(CODE_REG, Address(THR, target::Thread::optimize_stub_offset()));
__ EnterStubFrame();
__ Push(ARGS_DESC_REG);
__ LoadImmediate(IP, 0);
__ Push(IP); // Setup space on stack for return value.
__ Push(R8);
__ CallRuntime(kOptimizeInvokedFunctionRuntimeEntry, 1);
__ Pop(R0); // Discard argument.
__ Pop(FUNCTION_REG); // Get Function object
__ Pop(ARGS_DESC_REG); // Restore argument descriptor.
__ LeaveStubFrame();
__ ldr(CODE_REG, FieldAddress(FUNCTION_REG, target::Function::code_offset()));
__ Branch(FieldAddress(FUNCTION_REG, target::Function::entry_point_offset()));
__ bkpt(0);
}
// Does identical check (object references are equal or not equal) with special
// checks for boxed numbers.
// LR: return address.
// Return Zero condition flag set if equal.
// Note: A Mint cannot contain a value that would fit in Smi.
static void GenerateIdenticalWithNumberCheckStub(Assembler* assembler,
const Register left,
const Register right,
const Register temp) {
Label reference_compare, done, check_mint;
// If any of the arguments is Smi do reference compare.
__ tst(left, Operand(kSmiTagMask));
__ b(&reference_compare, EQ);
__ tst(right, Operand(kSmiTagMask));
__ b(&reference_compare, EQ);
// Value compare for two doubles.
__ CompareClassId(left, kDoubleCid, temp);
__ b(&check_mint, NE);
__ CompareClassId(right, kDoubleCid, temp);
__ b(&done, NE);
// Double values bitwise compare.
__ ldr(temp, FieldAddress(left, target::Double::value_offset() +
0 * target::kWordSize));
__ ldr(IP, FieldAddress(right, target::Double::value_offset() +
0 * target::kWordSize));
__ cmp(temp, Operand(IP));
__ b(&done, NE);
__ ldr(temp, FieldAddress(left, target::Double::value_offset() +
1 * target::kWordSize));
__ ldr(IP, FieldAddress(right, target::Double::value_offset() +
1 * target::kWordSize));
__ cmp(temp, Operand(IP));
__ b(&done);
__ Bind(&check_mint);
__ CompareClassId(left, kMintCid, temp);
__ b(&reference_compare, NE);
__ CompareClassId(right, kMintCid, temp);
__ b(&done, NE);
__ ldr(temp, FieldAddress(
left, target::Mint::value_offset() + 0 * target::kWordSize));
__ ldr(IP, FieldAddress(
right, target::Mint::value_offset() + 0 * target::kWordSize));
__ cmp(temp, Operand(IP));
__ b(&done, NE);
__ ldr(temp, FieldAddress(
left, target::Mint::value_offset() + 1 * target::kWordSize));
__ ldr(IP, FieldAddress(
right, target::Mint::value_offset() + 1 * target::kWordSize));
__ cmp(temp, Operand(IP));
__ b(&done);
__ Bind(&reference_compare);
__ cmp(left, Operand(right));
__ Bind(&done);
}
// Called only from unoptimized code. All relevant registers have been saved.
// LR: return address.
// SP + 4: left operand.
// SP + 0: right operand.
// Return Zero condition flag set if equal.
void StubCodeCompiler::GenerateUnoptimizedIdenticalWithNumberCheckStub() {
#if !defined(PRODUCT)
// Check single stepping.
Label stepping, done_stepping;
__ LoadIsolate(R1);
__ ldrb(R1, Address(R1, target::Isolate::single_step_offset()));
__ CompareImmediate(R1, 0);
__ b(&stepping, NE);
__ Bind(&done_stepping);
#endif
const Register temp = R2;
const Register left = R1;
const Register right = R0;
__ ldr(left, Address(SP, 1 * target::kWordSize));
__ ldr(right, Address(SP, 0 * target::kWordSize));
GenerateIdenticalWithNumberCheckStub(assembler, left, right, temp);
__ Ret();
#if !defined(PRODUCT)
__ Bind(&stepping);
__ EnterStubFrame();
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ RestoreCodePointer();
__ LeaveStubFrame();
__ b(&done_stepping);
#endif
}
// Called from optimized code only.
// LR: return address.
// SP + 4: left operand.
// SP + 0: right operand.
// Return Zero condition flag set if equal.
void StubCodeCompiler::GenerateOptimizedIdenticalWithNumberCheckStub() {
const Register temp = R2;
const Register left = R1;
const Register right = R0;
__ ldr(left, Address(SP, 1 * target::kWordSize));
__ ldr(right, Address(SP, 0 * target::kWordSize));
GenerateIdenticalWithNumberCheckStub(assembler, left, right, temp);
__ Ret();
}
// Called from megamorphic calls.
// R0: receiver
// IC_DATA_REG: MegamorphicCache (preserved)
// Passed to target:
// FUNCTION_REG: target function
// ARGS_DESC_REG: arguments descriptor
// CODE_REG: target Code
void StubCodeCompiler::GenerateMegamorphicCallStub() {
__ LoadTaggedClassIdMayBeSmi(R8, R0);
// R8: receiver cid as Smi.
__ ldr(R2,
FieldAddress(IC_DATA_REG, target::MegamorphicCache::buckets_offset()));
__ ldr(R1,
FieldAddress(IC_DATA_REG, target::MegamorphicCache::mask_offset()));
// R2: cache buckets array.
// R1: mask as a smi.
// Compute the table index.
ASSERT(target::MegamorphicCache::kSpreadFactor == 7);
// Use reverse subtract to multiply with 7 == 8 - 1.
__ rsb(R3, R8, Operand(R8, LSL, 3));
// R3: probe.
Label loop;
__ Bind(&loop);
__ and_(R3, R3, Operand(R1));
const intptr_t base = target::Array::data_offset();
// R3 is smi tagged, but table entries are two words, so LSL 2.
Label probe_failed;
__ add(IP, R2, Operand(R3, LSL, 2));
__ ldr(R6, FieldAddress(IP, base));
__ cmp(R6, Operand(R8));
__ b(&probe_failed, NE);
Label load_target;
__ Bind(&load_target);
// Call the target found in the cache. For a class id match, this is a
// proper target for the given name and arguments descriptor. If the
// illegal class id was found, the target is a cache miss handler that can
// be invoked as a normal Dart function.
__ ldr(FUNCTION_REG, FieldAddress(IP, base + target::kWordSize));
if (!FLAG_precompiled_mode) {
__ ldr(CODE_REG,
FieldAddress(FUNCTION_REG, target::Function::code_offset()));
}
__ ldr(ARGS_DESC_REG,
FieldAddress(IC_DATA_REG,
target::CallSiteData::arguments_descriptor_offset()));
__ Branch(FieldAddress(FUNCTION_REG, target::Function::entry_point_offset()));
// Probe failed, check if it is a miss.
__ Bind(&probe_failed);
ASSERT(kIllegalCid == 0);
__ tst(R6, Operand(R6));
Label miss;
__ b(&miss, EQ); // branch if miss.
// Try next entry in the table.
__ AddImmediate(R3, target::ToRawSmi(1));
__ b(&loop);
__ Bind(&miss);
GenerateSwitchableCallMissStub();
}
void StubCodeCompiler::GenerateICCallThroughCodeStub() {
Label loop, found, miss;
__ ldr(R8, FieldAddress(IC_DATA_REG, target::ICData::entries_offset()));
__ ldr(R4, FieldAddress(IC_DATA_REG,
target::CallSiteData::arguments_descriptor_offset()));
__ AddImmediate(R8, target::Array::data_offset() - kHeapObjectTag);
// R8: first IC entry
__ LoadTaggedClassIdMayBeSmi(R1, R0);
// R1: receiver cid as Smi
__ Bind(&loop);
__ ldr(R2, Address(R8, 0));
__ cmp(R1, Operand(R2));
__ b(&found, EQ);
__ CompareImmediate(R2, target::ToRawSmi(kIllegalCid));
__ b(&miss, EQ);
const intptr_t entry_length =
target::ICData::TestEntryLengthFor(1, /*tracking_exactness=*/false) *
target::kWordSize;
__ AddImmediate(R8, entry_length); // Next entry.
__ b(&loop);
__ Bind(&found);
if (FLAG_precompiled_mode) {
const intptr_t entry_offset =
target::ICData::EntryPointIndexFor(1) * target::kWordSize;
__ LoadCompressed(FUNCTION_REG, Address(R8, entry_offset));
__ Branch(
FieldAddress(FUNCTION_REG, target::Function::entry_point_offset()));
} else {
const intptr_t code_offset =
target::ICData::CodeIndexFor(1) * target::kWordSize;
__ LoadCompressed(CODE_REG, Address(R8, code_offset));
__ Branch(FieldAddress(CODE_REG, target::Code::entry_point_offset()));
}
__ Bind(&miss);
__ Branch(Address(THR, target::Thread::switchable_call_miss_entry_offset()));
}
// Implement the monomorphic entry check for call-sites where the receiver
// might be a Smi.
//
// R0: receiver
// R9: MonomorphicSmiableCall object
//
// R2, R3: clobbered
void StubCodeCompiler::GenerateMonomorphicSmiableCheckStub() {
__ LoadClassIdMayBeSmi(IP, R0);
// entrypoint_ should come right after expected_cid_
ASSERT(target::MonomorphicSmiableCall::entrypoint_offset() ==
target::MonomorphicSmiableCall::expected_cid_offset() +
target::kWordSize);
// Note: this stub is only used in AOT mode, hence the direct (bare) call.
// Simultaneously load the expected cid into R2 and the entrypoint into R3.
__ ldrd(
R2, R3, R9,
target::MonomorphicSmiableCall::expected_cid_offset() - kHeapObjectTag);
__ cmp(R2, Operand(IP));
__ Branch(Address(THR, target::Thread::switchable_call_miss_entry_offset()),
NE);
__ bx(R3);
}
static void CallSwitchableCallMissRuntimeEntry(Assembler* assembler,
Register receiver_reg) {
__ LoadImmediate(IP, 0);
__ Push(IP); // Result slot
__ Push(IP); // Arg0: stub out
__ Push(receiver_reg); // Arg1: Receiver
__ CallRuntime(kSwitchableCallMissRuntimeEntry, 2);
__ Pop(R0); // Get the receiver
__ Pop(CODE_REG); // result = stub
__ Pop(R9); // result = IC
}
// Called from switchable IC calls.
// R0: receiver
void StubCodeCompiler::GenerateSwitchableCallMissStub() {
__ ldr(CODE_REG,
Address(THR, target::Thread::switchable_call_miss_stub_offset()));
__ EnterStubFrame();
CallSwitchableCallMissRuntimeEntry(assembler, /*receiver_reg=*/R0);
__ LeaveStubFrame();
__ Branch(FieldAddress(
CODE_REG, target::Code::entry_point_offset(CodeEntryKind::kNormal)));
}
// Called from switchable IC calls.
// R0: receiver
// R9: SingleTargetCache
// Passed to target:
// CODE_REG: target Code object
void StubCodeCompiler::GenerateSingleTargetCallStub() {
Label miss;
__ LoadClassIdMayBeSmi(R1, R0);
__ ldrh(R2,
FieldAddress(R9, target::SingleTargetCache::lower_limit_offset()));
__ ldrh(R3,
FieldAddress(R9, target::SingleTargetCache::upper_limit_offset()));
__ cmp(R1, Operand(R2));
__ b(&miss, LT);
__ cmp(R1, Operand(R3));
__ b(&miss, GT);
__ ldr(CODE_REG,
FieldAddress(R9, target::SingleTargetCache::target_offset()));
__ Branch(FieldAddress(R9, target::SingleTargetCache::entry_point_offset()));
__ Bind(&miss);
__ EnterStubFrame();
CallSwitchableCallMissRuntimeEntry(assembler, /*receiver_reg=*/R0);
__ LeaveStubFrame();
__ Branch(FieldAddress(
CODE_REG, target::Code::entry_point_offset(CodeEntryKind::kMonomorphic)));
}
static int GetScaleFactor(intptr_t size) {
switch (size) {
case 1:
return 0;
case 2:
return 1;
case 4:
return 2;
case 8:
return 3;
case 16:
return 4;
}
UNREACHABLE();
return -1;
}
void StubCodeCompiler::GenerateAllocateTypedDataArrayStub(intptr_t cid) {
const intptr_t element_size = TypedDataElementSizeInBytes(cid);
const intptr_t max_len = TypedDataMaxNewSpaceElements(cid);
const intptr_t scale_shift = GetScaleFactor(element_size);
COMPILE_ASSERT(AllocateTypedDataArrayABI::kLengthReg == R4);
COMPILE_ASSERT(AllocateTypedDataArrayABI::kResultReg == R0);
if (!FLAG_use_slow_path && FLAG_inline_alloc) {
Label call_runtime;
NOT_IN_PRODUCT(__ MaybeTraceAllocation(cid, &call_runtime, R2));
__ mov(R2, Operand(AllocateTypedDataArrayABI::kLengthReg));
/* Check that length is a positive Smi. */
/* R2: requested array length argument. */
__ tst(R2, Operand(kSmiTagMask));
__ b(&call_runtime, NE);
__ SmiUntag(R2);
/* Check for length >= 0 && length <= max_len. */
/* R2: untagged array length. */
__ CompareImmediate(R2, max_len);
__ b(&call_runtime, HI);
__ mov(R2, Operand(R2, LSL, scale_shift));
const intptr_t fixed_size_plus_alignment_padding =
target::TypedData::HeaderSize() +
target::ObjectAlignment::kObjectAlignment - 1;
__ AddImmediate(R2, fixed_size_plus_alignment_padding);
__ bic(R2, R2, Operand(target::ObjectAlignment::kObjectAlignment - 1));
__ ldr(R0, Address(THR, target::Thread::top_offset()));
/* R2: allocation size. */
__ adds(R1, R0, Operand(R2));
__ b(&call_runtime, CS); /* Fail on unsigned overflow. */
/* Check if the allocation fits into the remaining space. */
/* R0: potential new object start. */
/* R1: potential next object start. */
/* R2: allocation size. */
__ ldr(IP, Address(THR, target::Thread::end_offset()));
__ cmp(R1, Operand(IP));
__ b(&call_runtime, CS);
__ CheckAllocationCanary(R0);
__ str(R1, Address(THR, target::Thread::top_offset()));
__ AddImmediate(R0, kHeapObjectTag);
/* Initialize the tags. */
/* R0: new object start as a tagged pointer. */
/* R1: new object end address. */
/* R2: allocation size. */
{
__ CompareImmediate(R2, target::UntaggedObject::kSizeTagMaxSizeTag);
__ mov(R3,
Operand(R2, LSL,
target::UntaggedObject::kTagBitsSizeTagPos -
target::ObjectAlignment::kObjectAlignmentLog2),
LS);
__ mov(R3, Operand(0), HI);
/* Get the class index and insert it into the tags. */
uword tags =
target::MakeTagWordForNewSpaceObject(cid, /*instance_size=*/0);
__ LoadImmediate(TMP, tags);
__ orr(R3, R3, Operand(TMP));
__ InitializeHeader(R3, R0);
}
/* Set the length field. */
/* R0: new object start as a tagged pointer. */
/* R1: new object end address. */
/* R2: allocation size. */
__ mov(R3,
Operand(AllocateTypedDataArrayABI::kLengthReg)); /* Array length. */
__ StoreIntoObjectNoBarrier(
R0, FieldAddress(R0, target::TypedDataBase::length_offset()), R3);
/* Initialize all array elements to 0. */
/* R0: new object start as a tagged pointer. */
/* R1: new object end address. */
/* R2: allocation size. */
/* R3: iterator which initially points to the start of the variable */
/* R8, R9: zero. */
/* data area to be initialized. */
__ LoadImmediate(R8, 0);
__ mov(R9, Operand(R8));
__ AddImmediate(R3, R0, target::TypedData::HeaderSize() - 1);
__ StoreInternalPointer(
R0, FieldAddress(R0, target::PointerBase::data_offset()), R3);
Label init_loop;
__ Bind(&init_loop);
__ AddImmediate(R3, 2 * target::kWordSize);
__ cmp(R3, Operand(R1));
__ strd(R8, R9, R3, -2 * target::kWordSize, LS);
__ b(&init_loop, CC);
__ str(R8, Address(R3, -2 * target::kWordSize), HI);
__ WriteAllocationCanary(R1); // Fix overshoot.
__ Ret();
__ Bind(&call_runtime);
}
__ EnterStubFrame();
__ PushObject(Object::null_object()); // Make room for the result.
__ PushImmediate(target::ToRawSmi(cid)); // Cid
__ Push(AllocateTypedDataArrayABI::kLengthReg); // Array length
__ CallRuntime(kAllocateTypedDataRuntimeEntry, 2);
__ Drop(2); // Drop arguments.
__ Pop(AllocateTypedDataArrayABI::kResultReg);
__ LeaveStubFrame();
__ Ret();
}
} // namespace compiler
} // namespace dart
#endif // defined(TARGET_ARCH_ARM)