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sdk/runtime/vm/compiler/stub_code_compiler_riscv.cc
T
Ryan Macnak 09b7f36b2f [vm, compiler] Support ShadowCallStack on Fuchsia RISC-V. 
Remove fixed uses of X18.

TEST=ci (Linux), speculative (Fuchsia)
Change-Id: I20e31fc2ab7d44cbf02e591be92261067158509d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/244943
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2022-05-16 22:35:55 +00:00

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// Copyright (c) 2021, 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/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_RISCV32) || defined(TARGET_ARCH_RISCV64)
#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/instructions.h"
#include "vm/static_type_exactness_state.h"
#include "vm/tags.h"
#define __ assembler->
namespace dart {
namespace compiler {
// Ensures that [A0] 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 [A0], [THR] and [FP].
// The caller should simply call LeaveStubFrame() and return.
void StubCodeCompiler::EnsureIsNewOrRemembered(Assembler* assembler,
bool preserve_registers) {
// If the object is not remembered we call a leaf-runtime to add it to the
// remembered set.
Label done;
__ andi(TMP2, A0, 1 << target::ObjectAlignment::kNewObjectBitPosition);
__ bnez(TMP2, &done);
{
LeafRuntimeScope rt(assembler, /*frame_size=*/0, preserve_registers);
// A0 already loaded.
__ mv(A1, THR);
rt.Call(kEnsureRememberedAndMarkingDeferredRuntimeEntry,
/*argument_count=*/2);
}
__ Bind(&done);
}
// Input parameters:
// RA : return address.
// SP : address of last argument in argument array.
// SP + 8*T4 - 8 : address of first argument in argument array.
// SP + 8*T4 : address of return value.
// T5 : address of the runtime function to call.
// T4 : number of arguments to the call.
void StubCodeCompiler::GenerateCallToRuntimeStub(Assembler* assembler) {
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();
__ Comment("CallToRuntimeStub");
__ lx(CODE_REG, Address(THR, target::Thread::call_to_runtime_stub_offset()));
__ SetPrologueOffset();
__ 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(TMP, target::Thread::exit_through_runtime_call());
__ StoreToOffset(TMP, THR, target::Thread::exit_through_ffi_offset());
#if defined(DEBUG)
{
Label ok;
// Check that we are always entering from Dart code.
__ LoadFromOffset(TMP, THR, target::Thread::vm_tag_offset());
__ CompareImmediate(TMP, VMTag::kDartTagId);
__ BranchIf(EQ, &ok);
__ Stop("Not coming from Dart code.");
__ Bind(&ok);
}
#endif
// Mark that the thread is executing VM code.
__ StoreToOffset(T5, THR, target::Thread::vm_tag_offset());
// Reserve space for arguments and align frame before entering C++ world.
// target::NativeArguments are passed in registers.
__ Comment("align stack");
// Reserve space for arguments.
ASSERT(target::NativeArguments::StructSize() == 4 * target::kWordSize);
__ ReserveAlignedFrameSpace(target::NativeArguments::StructSize());
// Pass target::NativeArguments structure by value and call runtime.
// Registers R0, R1, R2, and R3 are used.
ASSERT(thread_offset == 0 * target::kWordSize);
// There are no runtime calls to closures, so we do not need to set the tag
// bits kClosureFunctionBit and kInstanceFunctionBit in argc_tag_.
ASSERT(argc_tag_offset == 1 * target::kWordSize);
ASSERT(argv_offset == 2 * target::kWordSize);
__ slli(T2, T4, target::kWordSizeLog2);
__ add(T2, FP, T2); // Compute argv.
// Set argv in target::NativeArguments.
__ AddImmediate(T2,
target::frame_layout.param_end_from_fp * target::kWordSize);
ASSERT(retval_offset == 3 * target::kWordSize);
__ AddImmediate(T3, T2, target::kWordSize);
__ StoreToOffset(THR, SP, thread_offset);
__ StoreToOffset(T4, SP, argc_tag_offset);
__ StoreToOffset(T2, SP, argv_offset);
__ StoreToOffset(T3, SP, retval_offset);
__ mv(A0, SP); // Pass the pointer to the target::NativeArguments.
ASSERT(IsAbiPreservedRegister(THR));
__ jalr(T5);
__ Comment("CallToRuntimeStub return");
// Refresh pinned registers values (inc. write barrier mask and null object).
__ RestorePinnedRegisters();
// Retval is next to 1st argument.
// Mark that the thread is executing Dart code.
__ LoadImmediate(TMP, VMTag::kDartTagId);
__ StoreToOffset(TMP, THR, target::Thread::vm_tag_offset());
// Mark that the thread has not exited generated Dart code.
__ StoreToOffset(ZR, THR, target::Thread::exit_through_ffi_offset());
// Reset exit frame information in Isolate's mutator thread structure.
__ StoreToOffset(ZR, 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 A0
// contains a return value and will save it in a GC-visible way. We therefore
// have to ensure A0 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(A0, 0);
__ ret();
}
void StubCodeCompiler::GenerateSharedStubGeneric(
Assembler* assembler,
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.
__ PushRegister(RA);
__ PushRegisters(all_registers);
__ lx(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 RA restored via LeaveStubFrame.
__ ret();
}
void StubCodeCompiler::GenerateSharedStub(
Assembler* assembler,
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) {
__ PushRegister(NULL_REG);
}
__ CallRuntime(*target, /*argument_count=*/0);
if (store_runtime_result_in_result_register) {
__ PopRegister(A0);
__ sx(A0, Address(FP, target::kWordSize *
StubCodeCompiler::WordOffsetFromFpToCpuRegister(
SharedSlowPathStubABI::kResultReg)));
}
};
GenerateSharedStubGeneric(assembler, save_fpu_registers,
self_code_stub_offset_from_thread, allow_return,
perform_runtime_call);
}
void StubCodeCompiler::GenerateEnterSafepointStub(Assembler* assembler) {
RegisterSet all_registers;
all_registers.AddAllGeneralRegisters();
__ PushRegisters(all_registers);
__ EnterFrame(0);
__ ReserveAlignedFrameSpace(0);
__ lx(TMP, Address(THR, kEnterSafepointRuntimeEntry.OffsetFromThread()));
__ jalr(TMP);
__ LeaveFrame();
__ PopRegisters(all_registers);
__ ret();
}
static void GenerateExitSafepointStubCommon(Assembler* assembler,
uword runtime_entry_offset) {
RegisterSet all_registers;
all_registers.AddAllGeneralRegisters();
__ PushRegisters(all_registers);
__ EnterFrame(0);
__ ReserveAlignedFrameSpace(0);
// 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(TMP, target::Thread::vm_execution_state());
__ sx(TMP, Address(THR, target::Thread::execution_state_offset()));
__ lx(TMP, Address(THR, runtime_entry_offset));
__ jalr(TMP);
__ LeaveFrame();
__ PopRegisters(all_registers);
__ ret();
}
void StubCodeCompiler::GenerateExitSafepointStub(Assembler* assembler) {
GenerateExitSafepointStubCommon(
assembler, kExitSafepointRuntimeEntry.OffsetFromThread());
}
void StubCodeCompiler::GenerateExitSafepointIgnoreUnwindInProgressStub(
Assembler* assembler) {
GenerateExitSafepointStubCommon(
assembler,
kExitSafepointIgnoreUnwindInProgressRuntimeEntry.OffsetFromThread());
}
// Calls native code within a safepoint.
//
// On entry:
// T0: target to call
// Stack: set up for native call (SP), aligned, CSP < SP
//
// On exit:
// S3: clobbered, although normally callee-saved
// Stack: preserved, CSP == SP
void StubCodeCompiler::GenerateCallNativeThroughSafepointStub(
Assembler* assembler) {
COMPILE_ASSERT(IsAbiPreservedRegister(S3));
__ mv(S3, RA);
__ LoadImmediate(T1, target::Thread::exit_through_ffi());
__ TransitionGeneratedToNative(T0, FPREG, T1 /*volatile*/,
/*enter_safepoint=*/true);
#if defined(DEBUG)
// Check SP alignment.
__ andi(T2 /*volatile*/, SP, ~(OS::ActivationFrameAlignment() - 1));
Label done;
__ beq(T2, SP, &done);
__ Breakpoint();
__ Bind(&done);
#endif
__ jalr(T0);
__ TransitionNativeToGenerated(T1, /*leave_safepoint=*/true);
__ jr(S3);
}
#if !defined(DART_PRECOMPILER)
void StubCodeCompiler::GenerateJITCallbackTrampolines(
Assembler* assembler,
intptr_t next_callback_id) {
#if defined(USING_SIMULATOR)
// TODO(37299): FFI is not support in SIMRISCV32/64.
__ ebreak();
#else
Label loaded_callback_id_hi;
// T1 is volatile and not used for passing any arguments.
COMPILE_ASSERT(!IsCalleeSavedRegister(T1) && !IsArgumentRegister(T1));
for (intptr_t i = 0;
i < NativeCallbackTrampolines::NumCallbackTrampolinesPerPage(); ++i) {
// We don't use LoadImmediate because we need the trampoline size to be
// fixed independently of the callback ID.
// lui has 20 bits of range.
__ lui_fixed(T1, (next_callback_id + i) << 12);
__ j(&loaded_callback_id_hi);
}
ASSERT(__ CodeSize() ==
kNativeCallbackTrampolineSize *
NativeCallbackTrampolines::NumCallbackTrampolinesPerPage());
const intptr_t shared_stub_start = __ CodeSize();
__ Bind(&loaded_callback_id_hi);
__ srai(T1, T1, 12);
// Save THR (callee-saved) and RA. Keeps stack aligned.
COMPILE_ASSERT(StubCodeCompiler::kNativeCallbackTrampolineStackDelta == 2);
__ PushRegisterPair(RA, THR);
COMPILE_ASSERT(!IsArgumentRegister(THR));
RegisterSet all_registers;
all_registers.AddAllArgumentRegisters();
// The call below might clobber T1 (volatile, holding callback_id).
all_registers.Add(Location::RegisterLocation(T1));
// Load the thread, verify the callback ID and exit the safepoint.
//
// We exit the safepoint inside DLRT_GetThreadForNativeCallbackTrampoline
// in order to safe code size on this shared stub.
{
__ PushRegisters(all_registers);
__ EnterFrame(0);
__ ReserveAlignedFrameSpace(0);
// Since DLRT_GetThreadForNativeCallbackTrampoline can theoretically be
// loaded anywhere, we use the same trick as before to ensure a predictable
// instruction sequence.
Label call;
__ mv(A0, T1);
const intptr_t kPCRelativeLoadOffset = 12;
intptr_t start = __ CodeSize();
__ auipc(T1, 0);
__ lx(T1, Address(T1, kPCRelativeLoadOffset));
__ j(&call);
ASSERT_EQUAL(__ CodeSize() - start, kPCRelativeLoadOffset);
#if XLEN == 32
__ Emit32(
reinterpret_cast<int32_t>(&DLRT_GetThreadForNativeCallbackTrampoline));
#else
__ Emit64(
reinterpret_cast<int64_t>(&DLRT_GetThreadForNativeCallbackTrampoline));
#endif
__ Bind(&call);
__ jalr(T1);
__ mv(THR, A0);
__ LeaveFrame();
__ PopRegisters(all_registers);
}
COMPILE_ASSERT(!IsCalleeSavedRegister(T2) && !IsArgumentRegister(T2));
COMPILE_ASSERT(!IsCalleeSavedRegister(T3) && !IsArgumentRegister(T3));
// Load the code object.
__ LoadFromOffset(T2, THR, compiler::target::Thread::callback_code_offset());
__ LoadCompressedFieldFromOffset(
T2, T2, compiler::target::GrowableObjectArray::data_offset());
__ LoadCompressed(
T2,
__ ElementAddressForRegIndex(
/*external=*/false,
/*array_cid=*/kArrayCid,
/*index_scale, smi-tagged=*/compiler::target::kCompressedWordSize * 2,
/*index_unboxed=*/false,
/*array=*/T2,
/*index=*/T1,
/*temp=*/T3));
__ LoadFieldFromOffset(T2, T2, compiler::target::Code::entry_point_offset());
// Clobbers all volatile registers, including the callback ID in T1.
__ jalr(T2);
// Clobbers TMP, TMP2 and T1 -- all volatile and not holding return values.
__ EnterFullSafepoint(/*scratch=*/T1);
__ PopRegisterPair(RA, THR);
__ ret();
ASSERT_EQUAL((__ CodeSize() - shared_stub_start),
kNativeCallbackSharedStubSize);
ASSERT(__ CodeSize() <= VirtualMemory::PageSize());
#if defined(DEBUG)
while (__ CodeSize() < VirtualMemory::PageSize()) {
__ ebreak();
}
#endif
#endif
}
#endif // !defined(DART_PRECOMPILER)
// T1: The extracted method.
// T4: The type_arguments_field_offset (or 0)
void StubCodeCompiler::GenerateBuildMethodExtractorStub(
Assembler* assembler,
const Code& closure_allocation_stub,
const Code& context_allocation_stub,
bool generic) {
const intptr_t kReceiverOffset = target::frame_layout.param_end_from_fp + 1;
__ EnterStubFrame();
// Build type_arguments vector (or null)
Label no_type_args;
__ lx(T3, Address(THR, target::Thread::object_null_offset()));
__ CompareImmediate(T4, 0);
__ BranchIf(EQ, &no_type_args);
__ lx(T0, Address(FP, kReceiverOffset * target::kWordSize));
__ add(TMP, T0, T4);
__ LoadCompressed(T3, Address(TMP, 0));
__ Bind(&no_type_args);
// Push type arguments & extracted method.
__ PushRegistersInOrder({T3, T1});
// Allocate context.
{
Label done, slow_path;
if (!FLAG_use_slow_path && FLAG_inline_alloc) {
__ TryAllocateArray(kContextCid, target::Context::InstanceSize(1),
&slow_path,
A0, // instance
T1, // end address
T2, T3);
__ StoreCompressedIntoObjectNoBarrier(
A0, FieldAddress(A0, target::Context::parent_offset()), NULL_REG);
__ LoadImmediate(T1, 1);
__ sw(T1, FieldAddress(A0, target::Context::num_variables_offset()));
__ j(&done, compiler::Assembler::kNearJump);
}
__ Bind(&slow_path);
__ LoadImmediate(/*num_vars=*/T1, 1);
__ LoadObject(CODE_REG, context_allocation_stub);
__ lx(RA, FieldAddress(CODE_REG, target::Code::entry_point_offset()));
__ jalr(RA);
__ Bind(&done);
}
// Put context in right register for AllocateClosure call.
__ MoveRegister(AllocateClosureABI::kContextReg, A0);
// Store receiver in context
__ lx(AllocateClosureABI::kScratchReg,
Address(FP, target::kWordSize * kReceiverOffset));
__ StoreCompressedIntoObject(
AllocateClosureABI::kContextReg,
FieldAddress(AllocateClosureABI::kContextReg,
target::Context::variable_offset(0)),
AllocateClosureABI::kScratchReg);
// Pop function before pushing context.
__ PopRegister(AllocateClosureABI::kFunctionReg);
// Allocate closure. After this point, we only use the registers in
// AllocateClosureABI.
__ LoadObject(CODE_REG, closure_allocation_stub);
__ lx(AllocateClosureABI::kScratchReg,
FieldAddress(CODE_REG, target::Code::entry_point_offset()));
__ jalr(AllocateClosureABI::kScratchReg);
// Populate closure object.
__ PopRegister(AllocateClosureABI::kScratchReg); // Pop type arguments.
__ StoreCompressedIntoObjectNoBarrier(
AllocateClosureABI::kResultReg,
FieldAddress(AllocateClosureABI::kResultReg,
target::Closure::instantiator_type_arguments_offset()),
AllocateClosureABI::kScratchReg);
// Keep delayed_type_arguments as null if non-generic (see Closure::New).
if (generic) {
__ LoadObject(AllocateClosureABI::kScratchReg, EmptyTypeArguments());
__ StoreCompressedIntoObjectNoBarrier(
AllocateClosureABI::kResultReg,
FieldAddress(AllocateClosureABI::kResultReg,
target::Closure::delayed_type_arguments_offset()),
AllocateClosureABI::kScratchReg);
}
__ LeaveStubFrame();
// No-op if the two are the same.
__ MoveRegister(A0, AllocateClosureABI::kResultReg);
__ Ret();
}
void StubCodeCompiler::GenerateDispatchTableNullErrorStub(
Assembler* assembler) {
__ EnterStubFrame();
__ SmiTag(DispatchTableNullErrorABI::kClassIdReg);
__ PushRegister(DispatchTableNullErrorABI::kClassIdReg);
__ CallRuntime(kDispatchTableNullErrorRuntimeEntry, /*argument_count=*/1);
// The NullError runtime entry does not return.
__ Breakpoint();
}
void StubCodeCompiler::GenerateRangeError(Assembler* assembler,
bool with_fpu_regs) {
auto perform_runtime_call = [&]() {
// If the generated code has unboxed index/length we need to box them before
// calling the runtime entry.
#if XLEN == 32
ASSERT(!GenericCheckBoundInstr::UseUnboxedRepresentation());
#else
if (GenericCheckBoundInstr::UseUnboxedRepresentation()) {
Label length, smi_case;
// The user-controlled index might not fit into a Smi.
__ mv(TMP, RangeErrorABI::kIndexReg);
__ SmiTag(RangeErrorABI::kIndexReg, RangeErrorABI::kIndexReg);
__ SmiUntag(TMP2, RangeErrorABI::kIndexReg);
__ beq(TMP, TMP2, &length); // No overflow.
{
// Allocate a mint, reload the two registers and popualte the mint.
__ PushRegister(NULL_REG);
__ CallRuntime(kAllocateMintRuntimeEntry, /*argument_count=*/0);
__ PopRegister(RangeErrorABI::kIndexReg);
__ lx(TMP,
Address(FP, target::kWordSize *
StubCodeCompiler::WordOffsetFromFpToCpuRegister(
RangeErrorABI::kIndexReg)));
__ sx(TMP, FieldAddress(RangeErrorABI::kIndexReg,
target::Mint::value_offset()));
__ lx(RangeErrorABI::kLengthReg,
Address(FP, target::kWordSize *
StubCodeCompiler::WordOffsetFromFpToCpuRegister(
RangeErrorABI::kLengthReg)));
}
// Length is guaranteed to be in positive Smi range (it comes from a load
// of a vm recognized array).
__ Bind(&length);
__ SmiTag(RangeErrorABI::kLengthReg);
}
#endif // XLEN != 32
__ PushRegistersInOrder(
{RangeErrorABI::kLengthReg, RangeErrorABI::kIndexReg});
__ CallRuntime(kRangeErrorRuntimeEntry, /*argument_count=*/2);
__ Breakpoint();
};
GenerateSharedStubGeneric(
assembler, /*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);
}
// Input parameters:
// RA : return address.
// SP : address of return value.
// T5 : address of the native function to call.
// T2 : address of first argument in argument array.
// T1 : 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(TMP, target::Thread::exit_through_runtime_call());
__ StoreToOffset(TMP, THR, target::Thread::exit_through_ffi_offset());
#if defined(DEBUG)
{
Label ok;
// Check that we are always entering from Dart code.
__ LoadFromOffset(TMP, THR, target::Thread::vm_tag_offset());
__ CompareImmediate(TMP, VMTag::kDartTagId);
__ BranchIf(EQ, &ok);
__ Stop("Not coming from Dart code.");
__ Bind(&ok);
}
#endif
// Mark that the thread is executing native code.
__ StoreToOffset(T5, 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.
ASSERT(thread_offset == 0 * target::kWordSize);
// There are no native calls to closures, so we do not need to set the tag
// bits kClosureFunctionBit and kInstanceFunctionBit in argc_tag_.
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);
__ AddImmediate(
T3, FP, (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.
__ StoreToOffset(THR, SP, thread_offset);
__ StoreToOffset(T1, SP, argc_tag_offset);
__ StoreToOffset(T2, SP, argv_offset);
__ StoreToOffset(T3, SP, retval_offset);
__ mv(A0, SP); // Pass the pointer to the target::NativeArguments.
__ mv(A1, T5); // Pass the function entrypoint to call.
// Call native function invocation wrapper or redirection via simulator.
ASSERT(IsAbiPreservedRegister(THR));
__ Call(wrapper);
// Refresh pinned registers values (inc. write barrier mask and null object).
__ RestorePinnedRegisters();
// Mark that the thread is executing Dart code.
__ LoadImmediate(TMP, VMTag::kDartTagId);
__ StoreToOffset(TMP, THR, target::Thread::vm_tag_offset());
// Mark that the thread has not exited generated Dart code.
__ StoreToOffset(ZR, THR, target::Thread::exit_through_ffi_offset());
// Reset exit frame information in Isolate's mutator thread structure.
__ StoreToOffset(ZR, 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(Assembler* assembler) {
GenerateCallNativeWithWrapperStub(
assembler,
Address(THR,
target::Thread::no_scope_native_wrapper_entry_point_offset()));
}
void StubCodeCompiler::GenerateCallAutoScopeNativeStub(Assembler* assembler) {
GenerateCallNativeWithWrapperStub(
assembler,
Address(THR,
target::Thread::auto_scope_native_wrapper_entry_point_offset()));
}
// Input parameters:
// RA : return address.
// SP : address of return value.
// R5 : 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(Assembler* assembler) {
GenerateCallNativeWithWrapperStub(
assembler,
Address(THR,
target::Thread::bootstrap_native_wrapper_entry_point_offset()));
}
// Input parameters:
// ARGS_DESC_REG: arguments descriptor array.
void StubCodeCompiler::GenerateCallStaticFunctionStub(Assembler* assembler) {
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
__ subi(SP, SP, 2 * target::kWordSize);
__ sx(ARGS_DESC_REG,
Address(SP, 1 * target::kWordSize)); // Preserve args descriptor.
__ sx(ZR, Address(SP, 0 * target::kWordSize)); // Result slot.
__ CallRuntime(kPatchStaticCallRuntimeEntry, 0);
__ lx(CODE_REG, Address(SP, 0 * target::kWordSize)); // Result.
__ lx(ARGS_DESC_REG,
Address(SP, 1 * target::kWordSize)); // Restore args descriptor.
__ addi(SP, SP, 2 * target::kWordSize);
__ LeaveStubFrame();
// Jump to the dart function.
__ LoadFieldFromOffset(TMP, CODE_REG, target::Code::entry_point_offset());
__ jr(TMP);
}
// 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(Assembler* assembler) {
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.
__ lx(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.
__ PushRegistersInOrder({ARGS_DESC_REG, ZR});
__ CallRuntime(kFixCallersTargetRuntimeEntry, 0);
// Get Code object result and restore arguments descriptor array.
__ PopRegister(CODE_REG);
__ PopRegister(ARGS_DESC_REG);
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ LoadFieldFromOffset(TMP, CODE_REG, target::Code::entry_point_offset());
__ jr(TMP);
__ 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.
__ lx(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 result slot, preserve receiver and
// push old cache value (also 2nd return value).
__ PushRegistersInOrder({ZR, A0, S5});
__ CallRuntime(kFixCallersTargetMonomorphicRuntimeEntry, 2);
__ PopRegister(S5); // Get target cache object.
__ PopRegister(A0); // Restore receiver.
__ PopRegister(CODE_REG); // Get target Code object.
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ LoadFieldFromOffset(
TMP, CODE_REG,
target::Code::entry_point_offset(CodeEntryKind::kMonomorphic));
__ jr(TMP);
}
// Called from object allocate instruction when the allocation stub has been
// disabled.
void StubCodeCompiler::GenerateFixAllocationStubTargetStub(
Assembler* assembler) {
// 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.
__ lx(CODE_REG,
Address(THR, target::Thread::fix_allocation_stub_code_offset()));
__ EnterStubFrame();
// Setup space on stack for return value.
__ PushRegister(ZR);
__ CallRuntime(kFixAllocationStubTargetRuntimeEntry, 0);
// Get Code object result.
__ PopRegister(CODE_REG);
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ LoadFieldFromOffset(TMP, CODE_REG, target::Code::entry_point_offset());
__ jr(TMP);
}
// Called from object allocate instruction when the allocation stub for a
// generic class has been disabled.
void StubCodeCompiler::GenerateFixParameterizedAllocationStubTargetStub(
Assembler* assembler) {
// 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.
__ lx(CODE_REG,
Address(THR, target::Thread::fix_allocation_stub_code_offset()));
__ EnterStubFrame();
// Preserve type arguments register.
__ PushRegister(AllocateObjectABI::kTypeArgumentsReg);
// Setup space on stack for return value.
__ PushRegister(ZR);
__ CallRuntime(kFixAllocationStubTargetRuntimeEntry, 0);
// Get Code object result.
__ PopRegister(CODE_REG);
// Restore type arguments register.
__ PopRegister(AllocateObjectABI::kTypeArgumentsReg);
// Remove the stub frame.
__ LeaveStubFrame();
// Jump to the dart function.
__ LoadFieldFromOffset(TMP, CODE_REG, target::Code::entry_point_offset());
__ jr(TMP);
}
// Input parameters:
// T2: smi-tagged argument count, may be zero.
// FP[target::frame_layout.param_end_from_fp + 1]: last argument.
static void PushArrayOfArguments(Assembler* assembler) {
COMPILE_ASSERT(AllocateArrayABI::kLengthReg == T2);
COMPILE_ASSERT(AllocateArrayABI::kTypeArgumentsReg == T1);
// Allocate array to store arguments of caller.
__ LoadObject(T1, NullObject());
// T1: null element type for raw Array.
// T2: smi-tagged argument count, may be zero.
__ JumpAndLink(StubCodeAllocateArray());
// A0: newly allocated array.
// T2: smi-tagged argument count, may be zero (was preserved by the stub).
__ PushRegister(A0); // Array is in A0 and on top of stack.
__ SmiUntag(T2);
__ slli(T1, T2, target::kWordSizeLog2);
__ add(T1, T1, FP);
__ AddImmediate(T1,
target::frame_layout.param_end_from_fp * target::kWordSize);
__ AddImmediate(T3, A0, target::Array::data_offset() - kHeapObjectTag);
// T1: address of first argument on stack.
// T3: address of first argument in array.
Label loop, loop_exit;
__ Bind(&loop);
__ beqz(T2, &loop_exit);
__ lx(T6, Address(T1, 0));
__ addi(T1, T1, -target::kWordSize);
__ StoreCompressedIntoObject(A0, Address(T3, 0), T6);
__ addi(T3, T3, target::kCompressedWordSize);
__ addi(T2, T2, -1);
__ j(&loop);
__ Bind(&loop_exit);
}
// Used by eager and lazy deoptimization. Preserve result in RAX 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 TagAndPushPP() below:
// +------------------+
// | Saved PP | <- PP
// +------------------+
// | PC marker | <- TOS
// +------------------+
// | Saved FP |
// +------------------+
// | return-address | (deoptimization point)
// +------------------+
// | Saved CODE_REG | <- FP of stub
// +------------------+
// | ... | <- 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.
__ EnterStubFrame();
// 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 - A0);
const intptr_t saved_exception_slot_from_fp =
target::frame_layout.first_local_from_fp + 1 -
(kNumberOfCpuRegisters - A0);
const intptr_t saved_stacktrace_slot_from_fp =
target::frame_layout.first_local_from_fp + 1 -
(kNumberOfCpuRegisters - A1);
// Result in A0 is preserved as part of pushing all registers below.
// Push registers in their enumeration order: lowest register number at
// lowest address.
__ subi(SP, SP, kNumberOfCpuRegisters * target::kWordSize);
for (intptr_t i = kNumberOfCpuRegisters - 1; i >= 0; i--) {
const Register r = static_cast<Register>(i);
if (r == CODE_REG) {
// Save the original value of CODE_REG pushed before invoking this stub
// instead of the value used to call this stub.
COMPILE_ASSERT(TMP > CODE_REG); // TMP saved first
__ lx(TMP, Address(FP, 0 * target::kWordSize));
__ sx(TMP, Address(SP, i * target::kWordSize));
} else {
__ sx(r, Address(SP, i * target::kWordSize));
}
}
__ subi(SP, SP, kNumberOfFpuRegisters * kFpuRegisterSize);
for (intptr_t i = kNumberOfFpuRegisters - 1; i >= 0; i--) {
FRegister freg = static_cast<FRegister>(i);
__ fsd(freg, Address(SP, i * kFpuRegisterSize));
}
{
__ mv(A0, SP); // Pass address of saved registers block.
LeafRuntimeScope rt(assembler,
/*frame_size=*/0,
/*preserve_registers=*/false);
bool is_lazy =
(kind == kLazyDeoptFromReturn) || (kind == kLazyDeoptFromThrow);
__ li(A1, is_lazy ? 1 : 0);
rt.Call(kDeoptimizeCopyFrameRuntimeEntry, 2);
// Result (A0) is stack-size (FP - SP) in bytes.
}
if (kind == kLazyDeoptFromReturn) {
// Restore result into T1 temporarily.
__ LoadFromOffset(T1, FP, saved_result_slot_from_fp * target::kWordSize);
} else if (kind == kLazyDeoptFromThrow) {
// Restore result into T1 temporarily.
__ LoadFromOffset(T1, FP, saved_exception_slot_from_fp * target::kWordSize);
__ LoadFromOffset(T2, FP,
saved_stacktrace_slot_from_fp * target::kWordSize);
}
// There is a Dart Frame on the stack. We must restore PP and leave frame.
__ RestoreCodePointer();
__ LeaveStubFrame();
__ sub(SP, FP, A0);
// 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) {
__ PushRegister(T1); // Preserve result as first local.
} else if (kind == kLazyDeoptFromThrow) {
// Preserve exception as first local.
// Preserve stacktrace as second local.
__ PushRegistersInOrder({T1, T2});
}
{
__ mv(A0, FP); // Pass last FP as parameter in R0.
LeafRuntimeScope rt(assembler,
/*frame_size=*/0,
/*preserve_registers=*/false);
rt.Call(kDeoptimizeFillFrameRuntimeEntry, 1);
}
if (kind == kLazyDeoptFromReturn) {
// Restore result into T1.
__ LoadFromOffset(
T1, FP, target::frame_layout.first_local_from_fp * target::kWordSize);
} else if (kind == kLazyDeoptFromThrow) {
// Restore result into T1.
__ LoadFromOffset(
T1, FP, target::frame_layout.first_local_from_fp * target::kWordSize);
__ LoadFromOffset(
T2, FP,
(target::frame_layout.first_local_from_fp - 1) * target::kWordSize);
}
// Code above cannot cause GC.
// There is a Dart Frame on the stack. We must restore PP and leave frame.
__ 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) {
__ PushRegister(T1); // Preserve result, it will be GC-d here.
} else if (kind == kLazyDeoptFromThrow) {
// Preserve exception, it will be GC-d here.
// Preserve stacktrace, it will be GC-d here.
__ PushRegistersInOrder({T1, T2});
}
__ PushRegister(ZR); // 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.
__ PopRegister(T2);
__ SmiUntag(T2);
if (kind == kLazyDeoptFromReturn) {
__ PopRegister(A0); // Restore result.
} else if (kind == kLazyDeoptFromThrow) {
__ PopRegister(A1); // Restore stacktrace.
__ PopRegister(A0); // Restore exception.
}
__ LeaveStubFrame();
// Remove materialization arguments.
__ add(SP, SP, T2);
// The caller is responsible for emitting the return instruction.
}
// A0: result, must be preserved
void StubCodeCompiler::GenerateDeoptimizeLazyFromReturnStub(
Assembler* assembler) {
// Push zap value instead of CODE_REG for lazy deopt.
__ LoadImmediate(TMP, kZapCodeReg);
__ PushRegister(TMP);
// Return address for "call" to deopt stub.
__ LoadImmediate(RA, kZapReturnAddress);
__ lx(CODE_REG,
Address(THR, target::Thread::lazy_deopt_from_return_stub_offset()));
GenerateDeoptimizationSequence(assembler, kLazyDeoptFromReturn);
__ ret();
}
// A0: exception, must be preserved
// A1: stacktrace, must be preserved
void StubCodeCompiler::GenerateDeoptimizeLazyFromThrowStub(
Assembler* assembler) {
// Push zap value instead of CODE_REG for lazy deopt.
__ LoadImmediate(TMP, kZapCodeReg);
__ PushRegister(TMP);
// Return address for "call" to deopt stub.
__ LoadImmediate(RA, kZapReturnAddress);
__ lx(CODE_REG,
Address(THR, target::Thread::lazy_deopt_from_throw_stub_offset()));
GenerateDeoptimizationSequence(assembler, kLazyDeoptFromThrow);
__ ret();
}
void StubCodeCompiler::GenerateDeoptimizeStub(Assembler* assembler) {
__ PushRegister(CODE_REG);
__ lx(CODE_REG, Address(THR, target::Thread::deoptimize_stub_offset()));
GenerateDeoptimizationSequence(assembler, kEagerDeopt);
__ ret();
}
// IC_DATA_REG: ICData/MegamorphicCache
static void GenerateNoSuchMethodDispatcherBody(Assembler* assembler) {
__ EnterStubFrame();
__ lx(ARGS_DESC_REG,
FieldAddress(IC_DATA_REG,
target::CallSiteData::arguments_descriptor_offset()));
// Load the receiver.
__ LoadCompressedSmiFieldFromOffset(
T2, ARGS_DESC_REG, target::ArgumentsDescriptor::size_offset());
__ slli(TMP, T2, target::kWordSizeLog2 - 1); // T2 is Smi.
__ add(TMP, TMP, FP);
__ LoadFromOffset(A0, TMP,
target::frame_layout.param_end_from_fp * target::kWordSize);
// Push: result slot, receiver, ICData/MegamorphicCache,
// arguments descriptor.
__ PushRegistersInOrder({ZR, A0, IC_DATA_REG, ARGS_DESC_REG});
// Adjust arguments count.
__ LoadCompressedSmiFieldFromOffset(
T3, ARGS_DESC_REG, target::ArgumentsDescriptor::type_args_len_offset());
Label args_count_ok;
__ beqz(T3, &args_count_ok, Assembler::kNearJump);
// Include the type arguments.
__ addi(T2, T2, target::ToRawSmi(1));
__ Bind(&args_count_ok);
// T2: Smi-tagged arguments array length.
PushArrayOfArguments(assembler);
const intptr_t kNumArgs = 4;
__ CallRuntime(kNoSuchMethodFromCallStubRuntimeEntry, kNumArgs);
__ Drop(4);
__ PopRegister(A0); // 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.
__ bne(T0, NULL_REG, call_target_function);
GenerateNoSuchMethodDispatcherBody(assembler);
}
// Input:
// ARGS_DESC_REG - arguments descriptor
// IC_DATA_REG - icdata/megamorphic_cache
void StubCodeCompiler::GenerateNoSuchMethodDispatcherStub(
Assembler* assembler) {
GenerateNoSuchMethodDispatcherBody(assembler);
}
// Called for inline allocation of arrays.
// Input registers (preserved):
// RA: return address.
// AllocateArrayABI::kLengthReg: array length as Smi.
// AllocateArrayABI::kTypeArgumentsReg: type arguments of array.
// Output registers:
// AllocateArrayABI::kResultReg: newly allocated array.
// Clobbered:
// T3, T4, T5
void StubCodeCompiler::GenerateAllocateArrayStub(Assembler* assembler) {
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 * kCompressedWordSize) + target::Array::header_size()).
// Check that length is a Smi.
__ BranchIfNotSmi(AllocateArrayABI::kLengthReg, &slow_case);
// Check length >= 0 && length <= kMaxNewSpaceElements
const intptr_t max_len =
target::ToRawSmi(target::Array::kMaxNewSpaceElements);
__ CompareImmediate(AllocateArrayABI::kLengthReg, max_len, kObjectBytes);
__ BranchIf(HI, &slow_case);
const intptr_t cid = kArrayCid;
NOT_IN_PRODUCT(__ MaybeTraceAllocation(kArrayCid, &slow_case, T4));
// Calculate and align allocation size.
// Load new object start and calculate next object start.
// AllocateArrayABI::kTypeArgumentsReg: type arguments of array.
// AllocateArrayABI::kLengthReg: array length as Smi.
__ lx(AllocateArrayABI::kResultReg,
Address(THR, target::Thread::top_offset()));
intptr_t fixed_size_plus_alignment_padding =
target::Array::header_size() +
target::ObjectAlignment::kObjectAlignment - 1;
// AllocateArrayABI::kLengthReg is Smi.
__ slli(T3, AllocateArrayABI::kLengthReg,
target::kWordSizeLog2 - kSmiTagSize);
__ AddImmediate(T3, fixed_size_plus_alignment_padding);
__ andi(T3, T3, ~(target::ObjectAlignment::kObjectAlignment - 1));
// AllocateArrayABI::kResultReg: potential new object start.
// T3: object size in bytes.
__ add(T4, AllocateArrayABI::kResultReg, T3);
// Branch if unsigned overflow.
__ bltu(T4, AllocateArrayABI::kResultReg, &slow_case);
// Check if the allocation fits into the remaining space.
// AllocateArrayABI::kResultReg: potential new object start.
// AllocateArrayABI::kTypeArgumentsReg: type arguments of array.
// AllocateArrayABI::kLengthReg: array length as Smi.
// T3: array size.
// T4: potential next object start.
__ LoadFromOffset(TMP, THR, target::Thread::end_offset());
__ bgeu(T4, TMP, &slow_case); // Branch if unsigned higher or equal.
// Successfully allocated the object(s), now update top to point to
// next object start and initialize the object.
// AllocateArrayABI::kResultReg: potential new object start.
// T3: array size.
// T4: potential next object start.
__ sx(T4, Address(THR, target::Thread::top_offset()));
__ addi(AllocateArrayABI::kResultReg, AllocateArrayABI::kResultReg,
kHeapObjectTag);
// AllocateArrayABI::kResultReg: new object start as a tagged pointer.
// AllocateArrayABI::kTypeArgumentsReg: type arguments of array.
// AllocateArrayABI::kLengthReg: array length as Smi.
// R3: array size.
// R7: new object end address.
// Store the type argument field.
__ StoreCompressedIntoObjectOffsetNoBarrier(
AllocateArrayABI::kResultReg, target::Array::type_arguments_offset(),
AllocateArrayABI::kTypeArgumentsReg);
// Set the length field.
__ StoreCompressedIntoObjectOffsetNoBarrier(AllocateArrayABI::kResultReg,
target::Array::length_offset(),
AllocateArrayABI::kLengthReg);
// Calculate the size tag.
// AllocateArrayABI::kResultReg: new object start as a tagged pointer.
// AllocateArrayABI::kLengthReg: array length as Smi.
// T3: array size.
// T4: new object end address.
const intptr_t shift = target::UntaggedObject::kTagBitsSizeTagPos -
target::ObjectAlignment::kObjectAlignmentLog2;
__ li(T5, 0);
__ CompareImmediate(T3, target::UntaggedObject::kSizeTagMaxSizeTag);
compiler::Label zero_tag;
__ BranchIf(UNSIGNED_GREATER, &zero_tag);
__ slli(T5, T3, shift);
__ Bind(&zero_tag);
// Get the class index and insert it into the tags.
const uword tags =
target::MakeTagWordForNewSpaceObject(cid, /*instance_size=*/0);
__ OrImmediate(T5, T5, tags);
__ StoreFieldToOffset(T5, AllocateArrayABI::kResultReg,
target::Array::tags_offset());
// Initialize all array elements to raw_null.
// AllocateArrayABI::kResultReg: new object start as a tagged pointer.
// R7: new object end address.
// AllocateArrayABI::kLengthReg: array length as Smi.
__ AddImmediate(T3, AllocateArrayABI::kResultReg,
target::Array::data_offset() - kHeapObjectTag);
// R3: iterator which initially points to the start of the variable
// data area to be initialized.
Label loop;
__ Bind(&loop);
for (intptr_t offset = 0; offset < target::kObjectAlignment;
offset += target::kCompressedWordSize) {
__ StoreCompressedIntoObjectNoBarrier(AllocateArrayABI::kResultReg,
Address(T3, offset), NULL_REG);
}
// Safe to only check every kObjectAlignment bytes instead of each word.
ASSERT(kAllocationRedZoneSize >= target::kObjectAlignment);
__ addi(T3, T3, target::kObjectAlignment);
__ bltu(T3, T4, &loop);
// Done allocating and initializing the array.
// AllocateArrayABI::kResultReg: new object.
// AllocateArrayABI::kLengthReg: array length as Smi (preserved).
__ 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();
__ subi(SP, SP, 3 * target::kWordSize);
__ sx(ZR, Address(SP, 2 * target::kWordSize)); // Result slot.
__ sx(AllocateArrayABI::kLengthReg, Address(SP, 1 * target::kWordSize));
__ sx(AllocateArrayABI::kTypeArgumentsReg,
Address(SP, 0 * target::kWordSize));
__ CallRuntime(kAllocateArrayRuntimeEntry, 2);
__ lx(AllocateArrayABI::kTypeArgumentsReg,
Address(SP, 0 * target::kWordSize));
__ lx(AllocateArrayABI::kLengthReg, Address(SP, 1 * target::kWordSize));
__ lx(AllocateArrayABI::kResultReg, Address(SP, 2 * target::kWordSize));
__ addi(SP, SP, 3 * target::kWordSize);
__ LeaveStubFrame();
// 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.
ASSERT(AllocateArrayABI::kResultReg == A0);
EnsureIsNewOrRemembered(assembler);
__ ret();
}
void StubCodeCompiler::GenerateAllocateMintSharedWithFPURegsStub(
Assembler* assembler) {
// 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(assembler, /*save_fpu_registers=*/true,
&kAllocateMintRuntimeEntry,
target::Thread::allocate_mint_with_fpu_regs_stub_offset(),
/*allow_return=*/true,
/*store_runtime_result_in_result_register=*/true);
}
void StubCodeCompiler::GenerateAllocateMintSharedWithoutFPURegsStub(
Assembler* assembler) {
// 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(
assembler, /*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:
// RA : points to return address.
// A0 : target code or entry point (in bare instructions mode).
// A1 : arguments descriptor array.
// A2 : arguments array.
// A3 : current thread.
// Beware! TMP == A3
void StubCodeCompiler::GenerateInvokeDartCodeStub(Assembler* assembler) {
__ Comment("InvokeDartCodeStub");
__ EnterFrame(0);
// Push code object to PC marker slot.
__ lx(TMP2, Address(A3, target::Thread::invoke_dart_code_stub_offset()));
__ PushRegister(TMP2);
#if defined(DART_TARGET_OS_FUCHSIA)
__ sx(S2, Address(A3, target::Thread::saved_shadow_call_stack_offset()));
#elif defined(USING_SHADOW_CALL_STACK)
#error Unimplemented
#endif
// TODO(riscv): Consider using only volatile FPU registers in Dart code so we
// don't need to save the preserved FPU registers here.
__ PushNativeCalleeSavedRegisters();
// Set up THR, which caches the current thread in Dart code.
if (THR != A3) {
__ mv(THR, A3);
}
// Refresh pinned registers values (inc. write barrier mask and null object).
__ RestorePinnedRegisters();
// Save the current VMTag on the stack.
__ LoadFromOffset(TMP, THR, target::Thread::vm_tag_offset());
__ PushRegister(TMP);
// Save top resource and top exit frame info. Use R6 as a temporary register.
// StackFrameIterator reads the top exit frame info saved in this frame.
__ LoadFromOffset(TMP, THR, target::Thread::top_resource_offset());
__ StoreToOffset(ZR, THR, target::Thread::top_resource_offset());
__ PushRegister(TMP);
__ LoadFromOffset(TMP, THR, target::Thread::exit_through_ffi_offset());
__ StoreToOffset(ZR, THR, target::Thread::exit_through_ffi_offset());
__ PushRegister(TMP);
__ LoadFromOffset(TMP, THR, target::Thread::top_exit_frame_info_offset());
__ StoreToOffset(ZR, THR, target::Thread::top_exit_frame_info_offset());
__ PushRegister(TMP);
// target::frame_layout.exit_link_slot_from_entry_fp must be kept in sync
// with the code below.
#if XLEN == 32
ASSERT_EQUAL(target::frame_layout.exit_link_slot_from_entry_fp, -42);
#elif XLEN == 64
ASSERT_EQUAL(target::frame_layout.exit_link_slot_from_entry_fp, -30);
#endif
// In debug mode, verify that we've pushed the top exit frame info at the
// correct offset from FP.
__ EmitEntryFrameVerification();
// Mark that the thread is executing Dart code. Do this after initializing the
// exit link for the profiler.
__ LoadImmediate(TMP, VMTag::kDartTagId);
__ StoreToOffset(TMP, THR, target::Thread::vm_tag_offset());
// Load arguments descriptor array, which is passed to Dart code.
__ LoadFromOffset(ARGS_DESC_REG, A1, VMHandles::kOffsetOfRawPtrInHandle);
// Load number of arguments into T5 and adjust count for type arguments.
__ LoadFieldFromOffset(T5, ARGS_DESC_REG,
target::ArgumentsDescriptor::count_offset());
__ LoadFieldFromOffset(T3, ARGS_DESC_REG,
target::ArgumentsDescriptor::type_args_len_offset());
__ SmiUntag(T5);
// Include the type arguments.
__ snez(T3, T3); // T3 <- T3 == 0 ? 0 : 1
__ add(T5, T5, T3);
// Compute address of 'arguments array' data area into A2.
__ LoadFromOffset(A2, A2, VMHandles::kOffsetOfRawPtrInHandle);
__ AddImmediate(A2, target::Array::data_offset() - kHeapObjectTag);
// Set up arguments for the Dart call.
Label push_arguments;
Label done_push_arguments;
__ beqz(T5, &done_push_arguments); // check if there are arguments.
__ LoadImmediate(T2, 0);
__ Bind(&push_arguments);
__ lx(T3, Address(A2, 0));
__ PushRegister(T3);
__ addi(T2, T2, 1);
__ addi(A2, A2, target::kWordSize);
__ blt(T2, T5, &push_arguments, compiler::Assembler::kNearJump);
__ Bind(&done_push_arguments);
if (FLAG_precompiled_mode) {
__ SetupGlobalPoolAndDispatchTable();
__ mv(CODE_REG, ZR); // GC-safe value into CODE_REG.
} else {
// We now load the pool pointer(PP) with a GC safe value as we are about to
// invoke dart code. We don't need a real object pool here.
__ li(PP, 1); // PP is untagged, callee will tag and spill PP.
__ lx(CODE_REG, Address(A0, VMHandles::kOffsetOfRawPtrInHandle));
__ lx(A0, FieldAddress(CODE_REG, target::Code::entry_point_offset()));
}
// Call the Dart code entrypoint.
__ jalr(A0); // ARGS_DESC_REG is the arguments descriptor array.
__ Comment("InvokeDartCodeStub return");
// Get rid of arguments pushed on the stack.
__ addi(
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 R6 as a temporary register for this.
__ PopRegister(TMP);
__ StoreToOffset(TMP, THR, target::Thread::top_exit_frame_info_offset());
__ PopRegister(TMP);
__ StoreToOffset(TMP, THR, target::Thread::exit_through_ffi_offset());
__ PopRegister(TMP);
__ StoreToOffset(TMP, THR, target::Thread::top_resource_offset());
// Restore the current VMTag from the stack.
__ PopRegister(TMP);
__ StoreToOffset(TMP, THR, target::Thread::vm_tag_offset());
__ PopNativeCalleeSavedRegisters();
// Restore the frame pointer and C stack pointer and return.
__ LeaveFrame();
__ ret();
}
// Helper to generate space allocation of context stub.
// This does not initialise the fields of the context.
// Input:
// T1: number of context variables.
// Output:
// A0: new allocated Context object.
// Clobbered:
// T2, T3, T4, TMP
static void GenerateAllocateContextSpaceStub(Assembler* assembler,
Label* slow_case) {
// First compute the rounded instance size.
// R1: number of context variables.
intptr_t fixed_size_plus_alignment_padding =
target::Context::header_size() +
target::ObjectAlignment::kObjectAlignment - 1;
__ slli(T2, T1, kCompressedWordSizeLog2);
__ AddImmediate(T2, fixed_size_plus_alignment_padding);
__ andi(T2, T2, ~(target::ObjectAlignment::kObjectAlignment - 1));
NOT_IN_PRODUCT(__ MaybeTraceAllocation(kContextCid, slow_case, T4));
// Now allocate the object.
// T1: number of context variables.
// T2: object size.
__ lx(A0, Address(THR, target::Thread::top_offset()));
__ add(T3, T2, A0);
// Check if the allocation fits into the remaining space.
// A0: potential new object.
// T1: number of context variables.
// T2: object size.
// T3: potential next object start.
__ lx(TMP, Address(THR, target::Thread::end_offset()));
__ CompareRegisters(T3, TMP);
__ BranchIf(CS, slow_case); // Branch if unsigned higher or equal.
// Successfully allocated the object, now update top to point to
// next object start and initialize the object.
// A0: new object.
// T1: number of context variables.
// T2: object size.
// T3: next object start.
__ sx(T3, Address(THR, target::Thread::top_offset()));
__ addi(A0, A0, kHeapObjectTag);
// Calculate the size tag.
// A0: new object.
// T1: number of context variables.
// T2: object size.
const intptr_t shift = target::UntaggedObject::kTagBitsSizeTagPos -
target::ObjectAlignment::kObjectAlignmentLog2;
__ li(T3, 0);
__ CompareImmediate(T2, target::UntaggedObject::kSizeTagMaxSizeTag);
// If no size tag overflow, shift R2 left, else set R2 to zero.
compiler::Label zero_tag;
__ BranchIf(HI, &zero_tag);
__ slli(T3, T2, shift);
__ Bind(&zero_tag);
// Get the class index and insert it into the tags.
// T3: size and bit tags.
const uword tags =
target::MakeTagWordForNewSpaceObject(kContextCid, /*instance_size=*/0);
__ OrImmediate(T3, T3, tags);
__ StoreFieldToOffset(T3, A0, target::Object::tags_offset());
// Setup up number of context variables field.
// A0: new object.
// T1: number of context variables as integer value (not object).
__ StoreFieldToOffset(T1, A0, target::Context::num_variables_offset(),
kFourBytes);
}
// Called for inline allocation of contexts.
// Input:
// T1: number of context variables.
// Output:
// A0: new allocated Context object.
void StubCodeCompiler::GenerateAllocateContextStub(Assembler* assembler) {
if (!FLAG_use_slow_path && FLAG_inline_alloc) {
Label slow_case;
GenerateAllocateContextSpaceStub(assembler, &slow_case);
// Setup the parent field.
// A0: new object.
// T1: number of context variables.
__ StoreCompressedIntoObjectOffset(A0, target::Context::parent_offset(),
NULL_REG);
// Initialize the context variables.
// A0: new object.
// T1: number of context variables.
{
Label loop, done;
__ AddImmediate(T3, A0,
target::Context::variable_offset(0) - kHeapObjectTag);
__ Bind(&loop);
__ subi(T1, T1, 1);
__ bltz(T1, &done);
__ sx(NULL_REG, Address(T3, 0));
__ addi(T3, T3, target::kCompressedWordSize);
__ j(&loop);
__ Bind(&done);
}
// Done allocating and initializing the context.
// A0: 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.
__ SmiTag(T1);
__ PushObject(NullObject());
__ PushRegister(T1);
__ CallRuntime(kAllocateContextRuntimeEntry, 1); // Allocate context.
__ Drop(1); // Pop number of context variables argument.
__ PopRegister(A0); // 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(assembler, /*preserve_registers=*/false);
// A0: new object
// Restore the frame pointer.
__ LeaveStubFrame();
__ ret();
}
// Called for clone of contexts.
// Input:
// T5: context variable to clone.
// Output:
// A0: new allocated Context object.
void StubCodeCompiler::GenerateCloneContextStub(Assembler* assembler) {
if (!FLAG_use_slow_path && FLAG_inline_alloc) {
Label slow_case;
// Load num. variable (int32) in the existing context.
__ lw(T1, FieldAddress(T5, target::Context::num_variables_offset()));
GenerateAllocateContextSpaceStub(assembler, &slow_case);
// Load parent in the existing context.
__ LoadCompressed(T3, FieldAddress(T5, target::Context::parent_offset()));
// Setup the parent field.
// A0: new context.
__ StoreCompressedIntoObjectNoBarrier(
A0, FieldAddress(A0, target::Context::parent_offset()), T3);
// Clone the context variables.
// A0: new context.
// T1: number of context variables.
{
Label loop, done;
// T3: Variable array address, new context.
__ AddImmediate(T3, A0,
target::Context::variable_offset(0) - kHeapObjectTag);
// T4: Variable array address, old context.
__ AddImmediate(T4, T5,
target::Context::variable_offset(0) - kHeapObjectTag);
__ Bind(&loop);
__ subi(T1, T1, 1);
__ bltz(T1, &done);
__ lx(T5, Address(T4, 0));
__ addi(T4, T4, target::kCompressedWordSize);
__ sx(T5, Address(T3, 0));
__ addi(T3, T3, target::kCompressedWordSize);
__ j(&loop);
__ Bind(&done);
}
// Done allocating and initializing the context.
// A0: new object.
__ ret();
__ Bind(&slow_case);
}
__ EnterStubFrame();
__ subi(SP, SP, 2 * target::kWordSize);
__ sx(NULL_REG, Address(SP, 1 * target::kWordSize)); // Result slot.
__ sx(T5, Address(SP, 0 * target::kWordSize)); // Context argument.
__ CallRuntime(kCloneContextRuntimeEntry, 1);
__ lx(A0, Address(SP, 1 * target::kWordSize)); // Context result.
__ subi(SP, SP, 2 * target::kWordSize);
// 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(assembler, /*preserve_registers=*/false);
// A0: new object
__ LeaveStubFrame();
__ ret();
}
void StubCodeCompiler::GenerateWriteBarrierWrappersStub(Assembler* assembler) {
for (intptr_t i = 0; i < kNumberOfCpuRegisters; ++i) {
if ((kDartAvailableCpuRegs & (1 << i)) == 0) continue;
Register reg = static_cast<Register>(i);
intptr_t start = __ CodeSize();
__ addi(SP, SP, -3 * target::kWordSize);
__ sx(RA, Address(SP, 2 * target::kWordSize));
__ sx(TMP, Address(SP, 1 * target::kWordSize));
__ sx(kWriteBarrierObjectReg, Address(SP, 0 * target::kWordSize));
__ mv(kWriteBarrierObjectReg, reg);
__ Call(Address(THR, target::Thread::write_barrier_entry_point_offset()));
__ lx(kWriteBarrierObjectReg, Address(SP, 0 * target::kWordSize));
__ lx(TMP, Address(SP, 1 * target::kWordSize));
__ lx(RA, Address(SP, 2 * target::kWordSize));
__ addi(SP, SP, 3 * target::kWordSize);
__ jr(TMP); // Return.
intptr_t end = __ CodeSize();
ASSERT_EQUAL(end - start, kStoreBufferWrapperSize);
}
}
// Helper stub to implement Assembler::StoreIntoObject/Array.
// Input parameters:
// A0: Object (old)
// A1: Value (old or new)
// A6: Slot
// If A1 is new, add A0 to the store buffer. Otherwise A1 is old, mark A1
// and add it to the mark list.
COMPILE_ASSERT(kWriteBarrierObjectReg == A0);
COMPILE_ASSERT(kWriteBarrierValueReg == A1);
COMPILE_ASSERT(kWriteBarrierSlotReg == A6);
static void GenerateWriteBarrierStubHelper(Assembler* assembler,
bool cards) {
Label add_to_mark_stack, remember_card, lost_race;
__ andi(TMP2, A1, 1 << target::ObjectAlignment::kNewObjectBitPosition);
__ beqz(TMP2, &add_to_mark_stack);
if (cards) {
__ lbu(TMP2, FieldAddress(A0, target::Object::tags_offset()));
__ andi(TMP2, TMP2, 1 << target::UntaggedObject::kCardRememberedBit);
__ bnez(TMP2, &remember_card);
} else {
#if defined(DEBUG)
Label ok;
__ lbu(TMP2, FieldAddress(A0, target::Object::tags_offset()));
__ andi(TMP2, TMP2, 1 << target::UntaggedObject::kCardRememberedBit);
__ beqz(TMP2, &ok, Assembler::kNearJump);
__ Stop("Wrong barrier!");
__ Bind(&ok);
#endif
}
// Spill T2, T3, T4.
__ subi(SP, SP, 3 * target::kWordSize);
__ sx(T2, Address(SP, 2 * target::kWordSize));
__ sx(T3, Address(SP, 1 * target::kWordSize));
__ sx(T4, Address(SP, 0 * target::kWordSize));
// Atomically clear kOldAndNotRememberedBit.
ASSERT(target::Object::tags_offset() == 0);
__ subi(T3, A0, kHeapObjectTag);
// T3: Untagged address of header word (amo's do not support offsets).
__ li(TMP2, ~(1 << target::UntaggedObject::kOldAndNotRememberedBit));
#if XLEN == 32
__ amoandw(TMP2, TMP2, Address(T3, 0));
#else
__ amoandd(TMP2, TMP2, Address(T3, 0));
#endif
__ andi(TMP2, TMP2, 1 << target::UntaggedObject::kOldAndNotRememberedBit);
__ beqz(TMP2, &lost_race); // Was already clear -> lost race.
// Load the StoreBuffer block out of the thread. Then load top_ out of the
// StoreBufferBlock and add the address to the pointers_.
__ LoadFromOffset(T4, THR, target::Thread::store_buffer_block_offset());
__ LoadFromOffset(T2, T4, target::StoreBufferBlock::top_offset(),
kUnsignedFourBytes);
__ slli(T3, T2, target::kWordSizeLog2);
__ add(T3, T4, T3);
__ StoreToOffset(A0, T3, target::StoreBufferBlock::pointers_offset());
// Increment top_ and check for overflow.
// T2: top_.
// T4: StoreBufferBlock.
Label overflow;
__ addi(T2, T2, 1);
__ StoreToOffset(T2, T4, target::StoreBufferBlock::top_offset(),
kUnsignedFourBytes);
__ CompareImmediate(T2, target::StoreBufferBlock::kSize);
// Restore values.
__ BranchIf(EQ, &overflow);
// Restore T2, T3, T4.
__ lx(T4, Address(SP, 0 * target::kWordSize));
__ lx(T3, Address(SP, 1 * target::kWordSize));
__ lx(T2, Address(SP, 2 * target::kWordSize));
__ addi(SP, SP, 3 * target::kWordSize);
__ ret();
// Handle overflow: Call the runtime leaf function.
__ Bind(&overflow);
// Restore T2, T3, T4.
__ lx(T4, Address(SP, 0 * target::kWordSize));
__ lx(T3, Address(SP, 1 * target::kWordSize));
__ lx(T2, Address(SP, 2 * target::kWordSize));
__ addi(SP, SP, 3 * target::kWordSize);
{
LeafRuntimeScope rt(assembler, /*frame_size=*/0,
/*preserve_registers=*/true);
__ mv(A0, THR);
rt.Call(kStoreBufferBlockProcessRuntimeEntry, /*argument_count=*/1);
}
__ ret();
__ Bind(&add_to_mark_stack);
// Spill T2, T3, T4.
__ subi(SP, SP, 3 * target::kWordSize);
__ sx(T2, Address(SP, 2 * target::kWordSize));
__ sx(T3, Address(SP, 1 * target::kWordSize));
__ sx(T4, Address(SP, 0 * target::kWordSize));
// Atomically clear kOldAndNotMarkedBit.
Label marking_overflow;
ASSERT(target::Object::tags_offset() == 0);
__ subi(T3, A1, kHeapObjectTag);
// T3: Untagged address of header word (amo's do not support offsets).
__ li(TMP2, ~(1 << target::UntaggedObject::kOldAndNotMarkedBit));
#if XLEN == 32
__ amoandw(TMP2, TMP2, Address(T3, 0));
#else
__ amoandd(TMP2, TMP2, Address(T3, 0));
#endif
__ andi(TMP2, TMP2, 1 << target::UntaggedObject::kOldAndNotMarkedBit);
__ beqz(TMP2, &lost_race); // Was already clear -> lost race.
__ LoadFromOffset(T4, THR, target::Thread::marking_stack_block_offset());
__ LoadFromOffset(T2, T4, target::MarkingStackBlock::top_offset(),
kUnsignedFourBytes);
__ slli(T3, T2, target::kWordSizeLog2);
__ add(T3, T4, T3);
__ StoreToOffset(A1, T3, target::MarkingStackBlock::pointers_offset());
__ addi(T2, T2, 1);
__ StoreToOffset(T2, T4, target::MarkingStackBlock::top_offset(),
kUnsignedFourBytes);
__ CompareImmediate(T2, target::MarkingStackBlock::kSize);
__ BranchIf(EQ, &marking_overflow);
// Restore T2, T3, T4.
__ lx(T4, Address(SP, 0 * target::kWordSize));
__ lx(T3, Address(SP, 1 * target::kWordSize));
__ lx(T2, Address(SP, 2 * target::kWordSize));
__ addi(SP, SP, 3 * target::kWordSize);
__ ret();
__ Bind(&marking_overflow);
// Restore T2, T3, T4.
__ lx(T4, Address(SP, 0 * target::kWordSize));
__ lx(T3, Address(SP, 1 * target::kWordSize));
__ lx(T2, Address(SP, 2 * target::kWordSize));
__ addi(SP, SP, 3 * target::kWordSize);
{
LeafRuntimeScope rt(assembler, /*frame_size=*/0,
/*preserve_registers=*/true);
__ mv(A0, THR);
rt.Call(kMarkingStackBlockProcessRuntimeEntry, /*argument_count=*/1);
}
__ ret();
__ Bind(&lost_race);
// Restore T2, T3, T4.
__ lx(T4, Address(SP, 0 * target::kWordSize));
__ lx(T3, Address(SP, 1 * target::kWordSize));
__ lx(T2, Address(SP, 2 * target::kWordSize));
__ addi(SP, SP, 3 * target::kWordSize);
__ ret();
if (cards) {
Label remember_card_slow;
// Get card table.
__ Bind(&remember_card);
__ AndImmediate(TMP, A0, target::kOldPageMask); // OldPage.
__ lx(TMP,
Address(TMP, target::OldPage::card_table_offset())); // Card table.
__ beqz(TMP, &remember_card_slow);
// Dirty the card.
__ AndImmediate(TMP, A0, target::kOldPageMask); // OldPage.
__ sub(A6, A6, TMP); // Offset in page.
__ lx(TMP,
Address(TMP, target::OldPage::card_table_offset())); // Card table.
__ srli(A6, A6, target::OldPage::kBytesPerCardLog2);
__ add(TMP, TMP, A6); // Card address.
__ sb(A0, Address(TMP, 0)); // Low byte of A0 is non-zero from object tag.
__ ret();
// Card table not yet allocated.
__ Bind(&remember_card_slow);
{
LeafRuntimeScope rt(assembler, /*frame_size=*/0,
/*preserve_registers=*/true);
__ mv(A0, A0); // Arg0 = Object
__ mv(A1, A6); // Arg1 = Slot
rt.Call(kRememberCardRuntimeEntry, /*argument_count=*/2);
}
__ ret();
}
}
void StubCodeCompiler::GenerateWriteBarrierStub(Assembler* assembler) {
GenerateWriteBarrierStubHelper(assembler, false);
}
void StubCodeCompiler::GenerateArrayWriteBarrierStub(Assembler* assembler) {
GenerateWriteBarrierStubHelper(assembler, true);
}
static void GenerateAllocateObjectHelper(Assembler* assembler,
bool is_cls_parameterized) {
const Register kTagsReg = AllocateObjectABI::kTagsReg;
{
Label slow_case;
const Register kNewTopReg = T3;
// Bump allocation.
{
const Register kInstanceSizeReg = T4;
const Register kEndReg = T5;
__ ExtractInstanceSizeFromTags(kInstanceSizeReg, kTagsReg);
// Load two words from Thread::top: top and end.
// AllocateObjectABI::kResultReg: potential next object start.
__ lx(AllocateObjectABI::kResultReg,
Address(THR, target::Thread::top_offset()));
__ lx(kEndReg, Address(THR, target::Thread::end_offset()));
__ add(kNewTopReg, AllocateObjectABI::kResultReg, kInstanceSizeReg);
__ CompareRegisters(kEndReg, kNewTopReg);
__ BranchIf(UNSIGNED_LESS_EQUAL, &slow_case);
// Successfully allocated the object, now update top to point to
// next object start and store the class in the class field of object.
__ sx(kNewTopReg, Address(THR, target::Thread::top_offset()));
} // kInstanceSizeReg = R4, kEndReg = R5
// Tags.
__ sx(kTagsReg, Address(AllocateObjectABI::kResultReg,
target::Object::tags_offset()));
// Initialize the remaining words of the object.
{
const Register kFieldReg = T4;
__ AddImmediate(kFieldReg, AllocateObjectABI::kResultReg,
target::Instance::first_field_offset());
Label loop;
__ Bind(&loop);
for (intptr_t offset = 0; offset < target::kObjectAlignment;
offset += target::kCompressedWordSize) {
__ StoreCompressedIntoObjectNoBarrier(AllocateObjectABI::kResultReg,
Address(kFieldReg, offset),
NULL_REG);
}
// Safe to only check every kObjectAlignment bytes instead of each word.
ASSERT(kAllocationRedZoneSize >= target::kObjectAlignment);
__ addi(kFieldReg, kFieldReg, target::kObjectAlignment);
__ bltu(kFieldReg, kNewTopReg, &loop);
} // kFieldReg = T4
if (is_cls_parameterized) {
Label not_parameterized_case;
const Register kClsIdReg = T4;
const Register kTypeOffsetReg = T5;
__ ExtractClassIdFromTags(kClsIdReg, kTagsReg);
// Load class' type_arguments_field offset in words.
__ LoadClassById(kTypeOffsetReg, kClsIdReg);
__ lw(
kTypeOffsetReg,
FieldAddress(kTypeOffsetReg,
target::Class::
host_type_arguments_field_offset_in_words_offset()));
// Set the type arguments in the new object.
__ slli(kTypeOffsetReg, kTypeOffsetReg, target::kWordSizeLog2);
__ add(kTypeOffsetReg, kTypeOffsetReg, AllocateObjectABI::kResultReg);
__ sx(AllocateObjectABI::kTypeArgumentsReg, Address(kTypeOffsetReg, 0));
__ Bind(&not_parameterized_case);
} // kClsIdReg = R4, kTypeOffestReg = R5
__ AddImmediate(AllocateObjectABI::kResultReg,
AllocateObjectABI::kResultReg, kHeapObjectTag);
__ ret();
__ Bind(&slow_case);
} // kNewTopReg = R3
// Fall back on slow case:
if (!is_cls_parameterized) {
__ mv(AllocateObjectABI::kTypeArgumentsReg, NULL_REG);
}
// Tail call to generic allocation stub.
__ lx(
TMP,
Address(THR, target::Thread::allocate_object_slow_entry_point_offset()));
__ jr(TMP);
}
// Called for inline allocation of objects (any class).
void StubCodeCompiler::GenerateAllocateObjectStub(Assembler* assembler) {
GenerateAllocateObjectHelper(assembler, /*is_cls_parameterized=*/false);
}
void StubCodeCompiler::GenerateAllocateObjectParameterizedStub(
Assembler* assembler) {
GenerateAllocateObjectHelper(assembler, /*is_cls_parameterized=*/true);
}
void StubCodeCompiler::GenerateAllocateObjectSlowStub(Assembler* assembler) {
if (!FLAG_precompiled_mode) {
__ lx(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::kTagsReg,
AllocateObjectABI::kTagsReg);
__ LoadClassById(A0, AllocateObjectABI::kTagsReg);
__ subi(SP, SP, 3 * target::kWordSize);
__ sx(ZR, Address(SP, 2 * target::kWordSize)); // Result slot.
__ sx(A0, Address(SP, 1 * target::kWordSize)); // Arg0: Class object.
__ sx(AllocateObjectABI::kTypeArgumentsReg,
Address(SP, 0 * target::kWordSize)); // Arg1: Type args or null.
__ CallRuntime(kAllocateObjectRuntimeEntry, 2);
__ lx(AllocateObjectABI::kResultReg, Address(SP, 2 * target::kWordSize));
__ addi(SP, SP, 3 * 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(assembler, /*preserve_registers=*/false);
__ LeaveStubFrame();
__ ret();
}
// Called for inline allocation of objects.
void StubCodeCompiler::GenerateAllocationStubForClass(
Assembler* assembler,
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);
RELEASE_ASSERT(AllocateObjectInstr::WillAllocateNewOrRemembered(cls));
// 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);
RELEASE_ASSERT(target::Heap::IsAllocatableInNewSpace(instance_size));
const uword tags =
target::MakeTagWordForNewSpaceObject(cls_id, instance_size);
// Note: Keep in sync with helper function.
const Register kTagsReg = AllocateObjectABI::kTagsReg;
ASSERT(kTagsReg != AllocateObjectABI::kTypeArgumentsReg);
__ LoadImmediate(kTagsReg, tags);
if (!FLAG_use_slow_path && FLAG_inline_alloc &&
!target::Class::TraceAllocation(cls) &&
target::SizeFitsInSizeTag(instance_size)) {
if (is_cls_parameterized) {
// TODO(41974): Assign all allocation stubs to the root loading unit?
if (false &&
!IsSameObject(NullObject(),
CastHandle<Object>(allocat_object_parametrized))) {
__ GenerateUnRelocatedPcRelativeTailCall();
unresolved_calls->Add(new UnresolvedPcRelativeCall(
__ CodeSize(), allocat_object_parametrized, /*is_tail_call=*/true));
} else {
__ lx(TMP,
Address(THR,
target::Thread::
allocate_object_parameterized_entry_point_offset()));
__ jr(TMP);
}
} else {
// TODO(41974): Assign all allocation stubs to the root loading unit?
if (false &&
!IsSameObject(NullObject(), CastHandle<Object>(allocate_object))) {
__ GenerateUnRelocatedPcRelativeTailCall();
unresolved_calls->Add(new UnresolvedPcRelativeCall(
__ CodeSize(), allocate_object, /*is_tail_call=*/true));
} else {
__ lx(
TMP,
Address(THR, target::Thread::allocate_object_entry_point_offset()));
__ jr(TMP);
}
}
} else {
if (!is_cls_parameterized) {
__ LoadObject(AllocateObjectABI::kTypeArgumentsReg, NullObject());
}
__ lx(TMP,
Address(THR,
target::Thread::allocate_object_slow_entry_point_offset()));
__ jr(TMP);
}
}
// 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:
// RA : return address.
// SP : address of last argument.
// S4: arguments descriptor array.
void StubCodeCompiler::GenerateCallClosureNoSuchMethodStub(
Assembler* assembler) {
__ EnterStubFrame();
// Load the receiver.
__ LoadCompressedSmiFieldFromOffset(
T2, S4, target::ArgumentsDescriptor::size_offset());
__ slli(TMP, T2, target::kWordSizeLog2 - 1); // T2 is Smi
__ add(TMP, TMP, FP);
__ LoadFromOffset(A0, TMP,
target::frame_layout.param_end_from_fp * target::kWordSize);
// Load the function.
__ LoadCompressedFieldFromOffset(TMP, A0, target::Closure::function_offset());
// Push result slot, receiver, function, arguments descriptor.
__ PushRegistersInOrder({ZR, A0, TMP, S4});
// Adjust arguments count.
__ LoadCompressedSmiFieldFromOffset(
T3, S4, target::ArgumentsDescriptor::type_args_len_offset());
Label args_count_ok;
__ beqz(T3, &args_count_ok, Assembler::kNearJump);
// Include the type arguments.
__ addi(T2, T2, target::ToRawSmi(1));
__ Bind(&args_count_ok);
// T2: 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.
__ ebreak();
}
// A6: function object.
// S5: 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(
Assembler* assembler) {
if (FLAG_precompiled_mode) {
__ Breakpoint();
return;
}
if (FLAG_trace_optimized_ic_calls) {
__ Stop("Unimplemented");
}
__ LoadFieldFromOffset(TMP, A6, target::Function::usage_counter_offset(),
kFourBytes);
__ addi(TMP, TMP, 1);
__ StoreFieldToOffset(TMP, A6, target::Function::usage_counter_offset(),
kFourBytes);
}
// Loads function into 'func_reg'.
void StubCodeCompiler::GenerateUsageCounterIncrement(Assembler* assembler,
Register func_reg) {
if (FLAG_precompiled_mode) {
__ trap();
return;
}
if (FLAG_optimization_counter_threshold >= 0) {
__ Comment("Increment function counter");
__ LoadFieldFromOffset(func_reg, IC_DATA_REG,
target::ICData::owner_offset());
__ LoadFieldFromOffset(
A1, func_reg, target::Function::usage_counter_offset(), kFourBytes);
__ AddImmediate(A1, 1);
__ StoreFieldToOffset(A1, func_reg,
target::Function::usage_counter_offset(), kFourBytes);
}
}
// Note: S5 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");
__ lx(A0, Address(SP, +1 * target::kWordSize)); // Left.
__ lx(A1, Address(SP, +0 * target::kWordSize)); // Right.
__ or_(TMP2, A0, A1);
__ andi(TMP2, TMP2, kSmiTagMask);
__ bnez(TMP2, not_smi_or_overflow);
switch (kind) {
case Token::kADD: {
__ AddBranchOverflow(A0, A0, A1, not_smi_or_overflow);
break;
}
case Token::kLT: {
// TODO(riscv): Bit tricks with stl and NULL_REG.
Label load_true, done;
__ blt(A0, A1, &load_true, compiler::Assembler::kNearJump);
__ LoadObject(A0, CastHandle<Object>(FalseObject()));
__ j(&done, Assembler::kNearJump);
__ Bind(&load_true);
__ LoadObject(A0, CastHandle<Object>(TrueObject()));
__ Bind(&done);
break;
}
case Token::kEQ: {
// TODO(riscv): Bit tricks with stl and NULL_REG.
Label load_true, done;
__ beq(A0, A1, &load_true, Assembler::kNearJump);
__ LoadObject(A0, CastHandle<Object>(FalseObject()));
__ j(&done, Assembler::kNearJump);
__ Bind(&load_true);
__ LoadObject(A0, CastHandle<Object>(TrueObject()));
__ Bind(&done);
break;
}
default:
UNIMPLEMENTED();
}
// S5: IC data object (preserved).
__ LoadFieldFromOffset(A6, IC_DATA_REG, target::ICData::entries_offset());
// R6: ic_data_array with check entries: classes and target functions.
__ AddImmediate(A6, target::Array::data_offset() - kHeapObjectTag);
// R6: 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);
__ LoadCompressedSmiFromOffset(TMP, A6, 0);
__ CompareImmediate(TMP, imm_smi_cid);
__ BranchIf(NE, &error);
__ LoadCompressedSmiFromOffset(TMP, A6, target::kCompressedWordSize);
__ CompareImmediate(TMP, imm_smi_cid);
__ BranchIf(EQ, &ok);
__ Bind(&error);
__ Stop("Incorrect IC data");
__ Bind(&ok);
#endif
if (FLAG_optimization_counter_threshold >= 0) {
const intptr_t count_offset =
target::ICData::CountIndexFor(num_args) * target::kCompressedWordSize;
// Update counter, ignore overflow.
__ LoadCompressedSmiFromOffset(A1, A6, count_offset);
__ addi(A1, A1, target::ToRawSmi(1));
__ StoreToOffset(A1, A6, count_offset);
}
__ ret();
}
// Saves the offset of the target entry-point (from the Function) into T6.
//
// 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;
__ LoadImmediate(T6, target::Function::entry_point_offset() - kHeapObjectTag);
__ j(&done, Assembler::kNearJump);
__ BindUncheckedEntryPoint();
__ LoadImmediate(
T6, target::Function::entry_point_offset(CodeEntryKind::kUnchecked) -
kHeapObjectTag);
__ Bind(&done);
}
// Generate inline cache check for 'num_args'.
// A0: receiver (if instance call)
// S5: ICData
// RA: 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(
Assembler* assembler,
intptr_t num_args,
const RuntimeEntry& handle_ic_miss,
Token::Kind kind,
Optimized optimized,
CallType type,
Exactness exactness) {
const bool save_entry_point = kind == Token::kILLEGAL;
if (FLAG_precompiled_mode) {
__ Breakpoint();
return;
}
if (save_entry_point) {
GenerateRecordEntryPoint(assembler);
// T6: untagged entry point offset
}
if (optimized == kOptimized) {
GenerateOptimizedUsageCounterIncrement(assembler);
} else {
GenerateUsageCounterIncrement(assembler, /*scratch=*/T0);
}
ASSERT(exactness == kIgnoreExactness); // Unimplemented.
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'.
__ LoadFromOffset(TMP, IC_DATA_REG,
target::ICData::state_bits_offset() - kHeapObjectTag,
kUnsignedFourBytes);
ASSERT(target::ICData::NumArgsTestedShift() == 0); // No shift needed.
__ andi(TMP, TMP, target::ICData::NumArgsTestedMask());
__ CompareImmediate(TMP2, num_args);
__ BranchIf(EQ, &ok, Assembler::kNearJump);
__ 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(TMP);
__ LoadFromOffset(TMP, TMP, target::Isolate::single_step_offset(),
kUnsignedByte);
__ bnez(TMP, &stepping);
__ 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");
// S5: IC data object (preserved).
__ LoadFieldFromOffset(A1, IC_DATA_REG, target::ICData::entries_offset());
// A1: ic_data_array with check entries: classes and target functions.
__ AddImmediate(A1, target::Array::data_offset() - kHeapObjectTag);
// A1: points directly to the first ic data array element.
if (type == kInstanceCall) {
__ LoadTaggedClassIdMayBeSmi(T1, A0);
__ LoadFieldFromOffset(ARGS_DESC_REG, IC_DATA_REG,
target::CallSiteData::arguments_descriptor_offset());
if (num_args == 2) {
__ LoadCompressedSmiFieldFromOffset(
A7, ARGS_DESC_REG, target::ArgumentsDescriptor::count_offset());
__ slli(A7, A7, target::kWordSizeLog2 - kSmiTagSize);
__ add(A7, SP, A7);
__ lx(A6, Address(A7, -2 * target::kWordSize));
__ LoadTaggedClassIdMayBeSmi(T2, A6);
}
} else {
__ LoadFieldFromOffset(ARGS_DESC_REG, IC_DATA_REG,
target::CallSiteData::arguments_descriptor_offset());
__ LoadCompressedSmiFieldFromOffset(
A7, ARGS_DESC_REG, target::ArgumentsDescriptor::count_offset());
__ slli(A7, A7, target::kWordSizeLog2 - kSmiTagSize);
__ add(A7, A7, SP);
__ lx(A6, Address(A7, -1 * target::kWordSize));
__ LoadTaggedClassIdMayBeSmi(T1, A6);
if (num_args == 2) {
__ lx(A6, Address(A7, -2 * target::kWordSize));
__ LoadTaggedClassIdMayBeSmi(T2, A6);
}
}
// T1: first argument class ID as Smi.
// T2: second argument class ID as Smi.
// S4: args descriptor
// We unroll the generic one that is generated once more than the others.
const bool optimize = kind == Token::kILLEGAL;
// Loop that checks if there is an IC data match.
Label loop, found, miss;
__ Comment("ICData loop");
__ Bind(&loop);
for (int unroll = optimize ? 4 : 2; unroll >= 0; unroll--) {
Label update;
__ LoadCompressedSmiFromOffset(A7, A1, 0);
if (num_args == 1) {
__ beq(A7, T1, &found); // Class id match?
} else {
__ bne(A7, T1, &update); // Continue.
__ LoadCompressedSmiFromOffset(A7, A1, target::kCompressedWordSize);
__ beq(A7, T2, &found); // Class id match?
}
__ Bind(&update);
const intptr_t entry_size = target::ICData::TestEntryLengthFor(
num_args, exactness == kCheckExactness) *
target::kCompressedWordSize;
__ AddImmediate(A1, entry_size); // Next entry.
__ CompareImmediate(A7, target::ToRawSmi(kIllegalCid)); // Done?
if (unroll == 0) {
__ BranchIf(NE, &loop);
} else {
__ BranchIf(EQ, &miss);
}
}
__ Bind(&miss);
__ Comment("IC miss");
// Compute address of arguments.
__ LoadCompressedSmiFieldFromOffset(
A7, ARGS_DESC_REG, target::ArgumentsDescriptor::count_offset());
__ slli(A7, A7, target::kWordSizeLog2 - kSmiTagSize);
__ add(A7, A7, SP);
__ subi(A7, A7, 1 * target::kWordSize);
// A7: address of receiver
// Create a stub frame as we are pushing some objects on the stack before
// calling into the runtime.
__ EnterStubFrame();
// Preserve IC data object and arguments descriptor array and
// setup space on stack for result (target code object).
__ PushRegistersInOrder({ARGS_DESC_REG, IC_DATA_REG});
if (save_entry_point) {
__ SmiTag(T6);
__ PushRegister(T6);
}
// Setup space on stack for the result (target code object).
__ PushRegister(ZR);
// Push call arguments.
for (intptr_t i = 0; i < num_args; i++) {
__ LoadFromOffset(TMP, A7, -target::kWordSize * i);
__ PushRegister(TMP);
}
// Pass IC data object.
__ PushRegister(IC_DATA_REG);
__ 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.
__ PopRegister(FUNCTION_REG); // Pop returned function object into T0.
if (save_entry_point) {
__ PopRegister(T6);
__ SmiUntag(T6);
}
__ PopRegister(IC_DATA_REG); // Restore IC Data.
__ PopRegister(ARGS_DESC_REG); // Restore arguments descriptor array.
__ RestoreCodePointer();
__ LeaveStubFrame();
Label call_target_function;
if (!FLAG_lazy_dispatchers) {
GenerateDispatcherCode(assembler, &call_target_function);
} else {
__ j(&call_target_function);
}
__ Bind(&found);
__ Comment("Update caller's counter");
// A1: pointer to an IC data check group.
const intptr_t target_offset =
target::ICData::TargetIndexFor(num_args) * target::kCompressedWordSize;
const intptr_t count_offset =
target::ICData::CountIndexFor(num_args) * target::kCompressedWordSize;
__ LoadCompressedFromOffset(FUNCTION_REG, A1, target_offset);
if (FLAG_optimization_counter_threshold >= 0) {
// Update counter, ignore overflow.
__ LoadCompressedSmiFromOffset(TMP, A1, count_offset);
__ addi(TMP, TMP, target::ToRawSmi(1));
__ StoreToOffset(TMP, A1, count_offset);
}
__ Comment("Call target");
__ Bind(&call_target_function);
// T0: target function.
__ LoadCompressedFieldFromOffset(CODE_REG, FUNCTION_REG,
target::Function::code_offset());
if (save_entry_point) {
__ add(A7, FUNCTION_REG, T6);
__ lx(A7, Address(A7, 0));
} else {
__ LoadFieldFromOffset(A7, FUNCTION_REG,
target::Function::entry_point_offset());
}
__ jr(A7); // FUNCTION_REG: Function, argument to lazy compile stub.
#if !defined(PRODUCT)
if (optimized == kUnoptimized) {
__ Bind(&stepping);
__ EnterStubFrame();
if (type == kInstanceCall) {
__ PushRegister(A0); // Preserve receiver.
}
if (save_entry_point) {
__ SmiTag(T6);
__ PushRegister(T6);
}
__ PushRegister(IC_DATA_REG); // Preserve IC data.
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ PopRegister(IC_DATA_REG);
if (save_entry_point) {
__ PopRegister(T6);
__ SmiUntag(T6);
}
if (type == kInstanceCall) {
__ PopRegister(A0);
}
__ RestoreCodePointer();
__ LeaveStubFrame();
__ j(&done_stepping);
}
#endif
}
// A0: receiver
// S5: ICData
// RA: return address
void StubCodeCompiler::GenerateOneArgCheckInlineCacheStub(
Assembler* assembler) {
GenerateNArgsCheckInlineCacheStub(
assembler, 1, kInlineCacheMissHandlerOneArgRuntimeEntry, Token::kILLEGAL,
kUnoptimized, kInstanceCall, kIgnoreExactness);
}
// A0: receiver
// S5: ICData
// RA: return address
void StubCodeCompiler::GenerateOneArgCheckInlineCacheWithExactnessCheckStub(
Assembler* assembler) {
__ Stop("Unimplemented");
}
// A0: receiver
// S5: ICData
// RA: return address
void StubCodeCompiler::GenerateTwoArgsCheckInlineCacheStub(
Assembler* assembler) {
GenerateNArgsCheckInlineCacheStub(
assembler, 2, kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kILLEGAL,
kUnoptimized, kInstanceCall, kIgnoreExactness);
}
// A0: receiver
// S5: ICData
// RA: return address
void StubCodeCompiler::GenerateSmiAddInlineCacheStub(Assembler* assembler) {
GenerateNArgsCheckInlineCacheStub(
assembler, 2, kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kADD,
kUnoptimized, kInstanceCall, kIgnoreExactness);
}
// A0: receiver
// S5: ICData
// RA: return address
void StubCodeCompiler::GenerateSmiLessInlineCacheStub(Assembler* assembler) {
GenerateNArgsCheckInlineCacheStub(
assembler, 2, kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kLT,
kUnoptimized, kInstanceCall, kIgnoreExactness);
}
// A0: receiver
// S5: ICData
// RA: return address
void StubCodeCompiler::GenerateSmiEqualInlineCacheStub(Assembler* assembler) {
GenerateNArgsCheckInlineCacheStub(
assembler, 2, kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kEQ,
kUnoptimized, kInstanceCall, kIgnoreExactness);
}
// A0: receiver
// S5: ICData
// A6: Function
// RA: return address
void StubCodeCompiler::GenerateOneArgOptimizedCheckInlineCacheStub(
Assembler* assembler) {
GenerateNArgsCheckInlineCacheStub(
assembler, 1, kInlineCacheMissHandlerOneArgRuntimeEntry, Token::kILLEGAL,
kOptimized, kInstanceCall, kIgnoreExactness);
}
// A0: receiver
// S5: ICData
// A6: Function
// RA: return address
void StubCodeCompiler::
GenerateOneArgOptimizedCheckInlineCacheWithExactnessCheckStub(
Assembler* assembler) {
__ Stop("Unimplemented");
}
// A0: receiver
// S5: ICData
// A6: Function
// RA: return address
void StubCodeCompiler::GenerateTwoArgsOptimizedCheckInlineCacheStub(
Assembler* assembler) {
GenerateNArgsCheckInlineCacheStub(
assembler, 2, kInlineCacheMissHandlerTwoArgsRuntimeEntry, Token::kILLEGAL,
kOptimized, kInstanceCall, kIgnoreExactness);
}
// S5: ICData
// RA: return address
void StubCodeCompiler::GenerateZeroArgsUnoptimizedStaticCallStub(
Assembler* assembler) {
GenerateRecordEntryPoint(assembler);
GenerateUsageCounterIncrement(assembler, /* scratch */ T0);
#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'.
__ LoadFromOffset(TMP, IC_DATA_REG,
target::ICData::state_bits_offset() - kHeapObjectTag,
kUnsignedFourBytes);
ASSERT(target::ICData::NumArgsTestedShift() == 0); // No shift needed.
__ andi(TMP, TMP, target::ICData::NumArgsTestedMask());
__ CompareImmediate(TMP, 0);
__ BranchIf(EQ, &ok);
__ Stop("Incorrect IC data for unoptimized static call");
__ Bind(&ok);
}
#endif // DEBUG
// Check single stepping.
#if !defined(PRODUCT)
Label stepping, done_stepping;
__ LoadIsolate(TMP);
__ LoadFromOffset(TMP, TMP, target::Isolate::single_step_offset(),
kUnsignedByte);
__ bnez(TMP, &stepping, Assembler::kNearJump);
__ Bind(&done_stepping);
#endif
// T5: IC data object (preserved).
__ LoadFieldFromOffset(A0, IC_DATA_REG, target::ICData::entries_offset());
// A0: ic_data_array with entries: target functions and count.
__ AddImmediate(A0, target::Array::data_offset() - kHeapObjectTag);
// A0: points directly to the first ic data array element.
const intptr_t target_offset =
target::ICData::TargetIndexFor(0) * target::kCompressedWordSize;
const intptr_t count_offset =
target::ICData::CountIndexFor(0) * target::kCompressedWordSize;
if (FLAG_optimization_counter_threshold >= 0) {
// Increment count for this call, ignore overflow.
__ LoadCompressedSmiFromOffset(TMP, A0, count_offset);
__ addi(TMP, TMP, target::ToRawSmi(1));
__ StoreToOffset(TMP, A0, count_offset);
}
// Load arguments descriptor into T4.
__ LoadFieldFromOffset(ARGS_DESC_REG, IC_DATA_REG,
target::CallSiteData::arguments_descriptor_offset());
// Get function and call it, if possible.
__ LoadCompressedFromOffset(FUNCTION_REG, A0, target_offset);
__ LoadCompressedFieldFromOffset(CODE_REG, FUNCTION_REG,
target::Function::code_offset());
__ add(A0, FUNCTION_REG, T6);
__ lx(TMP, Address(A0, 0));
__ jr(TMP); // FUNCTION_REG: Function, argument to lazy compile stub.
#if !defined(PRODUCT)
__ Bind(&stepping);
__ EnterStubFrame();
__ PushRegister(IC_DATA_REG); // Preserve IC data.
__ SmiTag(T6);
__ PushRegister(T6);
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ PopRegister(T6);
__ SmiUntag(T6);
__ PopRegister(IC_DATA_REG);
__ RestoreCodePointer();
__ LeaveStubFrame();
__ j(&done_stepping);
#endif
}
// S5: ICData
// RA: return address
void StubCodeCompiler::GenerateOneArgUnoptimizedStaticCallStub(
Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, /* scratch */ T0);
GenerateNArgsCheckInlineCacheStub(
assembler, 1, kStaticCallMissHandlerOneArgRuntimeEntry, Token::kILLEGAL,
kUnoptimized, kStaticCall, kIgnoreExactness);
}
// S5: ICData
// RA: return address
void StubCodeCompiler::GenerateTwoArgsUnoptimizedStaticCallStub(
Assembler* assembler) {
GenerateUsageCounterIncrement(assembler, /* scratch */ T0);
GenerateNArgsCheckInlineCacheStub(
assembler, 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(Assembler* assembler) {
// Preserve arg desc.
__ EnterStubFrame();
// Save arguments descriptor and pass function.
__ PushRegistersInOrder({ARGS_DESC_REG, FUNCTION_REG});
__ CallRuntime(kCompileFunctionRuntimeEntry, 1);
__ PopRegister(FUNCTION_REG); // Restore function.
__ PopRegister(ARGS_DESC_REG); // Restore arg desc.
__ LeaveStubFrame();
__ LoadCompressedFieldFromOffset(CODE_REG, FUNCTION_REG,
target::Function::code_offset());
__ LoadFieldFromOffset(TMP, FUNCTION_REG,
target::Function::entry_point_offset());
__ jr(TMP);
}
// A0: Receiver
// S5: ICData
void StubCodeCompiler::GenerateICCallBreakpointStub(Assembler* assembler) {
#if defined(PRODUCT)
__ Stop("No debugging in PRODUCT mode");
#else
__ EnterStubFrame();
__ subi(SP, SP, 3 * target::kWordSize);
__ sx(A0, Address(SP, 2 * target::kWordSize)); // Preserve receiver.
__ sx(S5, Address(SP, 1 * target::kWordSize)); // Preserve IC data.
__ sx(ZR, Address(SP, 0 * target::kWordSize)); // Space for result.
__ CallRuntime(kBreakpointRuntimeHandlerRuntimeEntry, 0);
__ lx(CODE_REG, Address(SP, 0 * target::kWordSize)); // Original stub.
__ lx(S5, Address(SP, 1 * target::kWordSize)); // Restore IC data.
__ lx(A0, Address(SP, 2 * target::kWordSize)); // Restore receiver.
__ LeaveStubFrame();
__ LoadFieldFromOffset(TMP, CODE_REG, target::Code::entry_point_offset());
__ jr(TMP);
#endif
}
// S5: ICData
void StubCodeCompiler::GenerateUnoptStaticCallBreakpointStub(
Assembler* assembler) {
#if defined(PRODUCT)
__ Stop("No debugging in PRODUCT mode");
#else
__ EnterStubFrame();
__ subi(SP, SP, 2 * target::kWordSize);
__ sx(S5, Address(SP, 1 * target::kWordSize)); // Preserve IC data.
__ sx(ZR, Address(SP, 0 * target::kWordSize)); // Space for result.
__ CallRuntime(kBreakpointRuntimeHandlerRuntimeEntry, 0);
__ lx(CODE_REG, Address(SP, 0 * target::kWordSize)); // Original stub.
__ lx(S5, Address(SP, 1 * target::kWordSize)); // Restore IC data.
__ LeaveStubFrame();
__ LoadFieldFromOffset(TMP, CODE_REG, target::Code::entry_point_offset());
__ jr(TMP);
#endif // defined(PRODUCT)
}
void StubCodeCompiler::GenerateRuntimeCallBreakpointStub(Assembler* assembler) {
#if defined(PRODUCT)
__ Stop("No debugging in PRODUCT mode");
#else
__ EnterStubFrame();
__ subi(SP, SP, 1 * target::kWordSize);
__ sx(ZR, Address(SP, 0 * target::kWordSize)); // Space for result.
__ CallRuntime(kBreakpointRuntimeHandlerRuntimeEntry, 0);
__ lx(CODE_REG, Address(SP, 0 * target::kWordSize));
__ LeaveStubFrame();
__ LoadFieldFromOffset(TMP, CODE_REG, target::Code::entry_point_offset());
__ jr(TMP);
#endif // defined(PRODUCT)
}
// Called only from unoptimized code. All relevant registers have been saved.
void StubCodeCompiler::GenerateDebugStepCheckStub(Assembler* assembler) {
#if defined(PRODUCT)
__ Stop("No debugging in PRODUCT mode");
#else
// Check single stepping.
Label stepping, done_stepping;
__ LoadIsolate(A1);
__ LoadFromOffset(A1, A1, target::Isolate::single_step_offset(),
kUnsignedByte);
__ bnez(A1, &stepping, compiler::Assembler::kNearJump);
__ Bind(&done_stepping);
__ ret();
__ Bind(&stepping);
__ EnterStubFrame();
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ LeaveStubFrame();
__ j(&done_stepping);
#endif // defined(PRODUCT)
}
// Used to check class and type arguments. Arguments passed in registers:
//
// Inputs (mostly from TypeTestABI struct):
// - kSubtypeTestCacheReg: UntaggedSubtypeTestCache
// - kInstanceReg: instance to test against.
// - kDstTypeReg: destination type (for n>=3).
// - kInstantiatorTypeArgumentsReg: instantiator type arguments (for n=5).
// - kFunctionTypeArgumentsReg: function type arguments (for n=5).
// - RA: return address.
//
// All input registers are preserved except for kSubtypeTestCacheReg, which
// should be saved by the caller if needed.
//
// Result in SubtypeTestCacheABI::kResultReg: null -> not found, otherwise
// result (true or false).
static void GenerateSubtypeNTestCacheStub(Assembler* assembler, int n) {
ASSERT(n == 1 || n == 3 || n == 5 || n == 7);
// Until we have the result, we use the result register to store the null
// value for quick access. This has the side benefit of initializing the
// result to null, so it only needs to be changed if found.
const Register kNullReg = TypeTestABI::kSubtypeTestCacheResultReg;
__ LoadObject(kNullReg, NullObject());
const Register kCacheArrayReg = TypeTestABI::kSubtypeTestCacheReg;
const Register kScratchReg = TypeTestABI::kScratchReg;
// All of these must be distinct from TypeTestABI::kSubtypeTestCacheResultReg
// since it is used for kNullReg as well.
// Loop initialization (moved up here to avoid having all dependent loads
// after each other).
// We avoid a load-acquire barrier here by relying on the fact that all other
// loads from the array are data-dependent loads.
__ lx(kCacheArrayReg, FieldAddress(TypeTestABI::kSubtypeTestCacheReg,
target::SubtypeTestCache::cache_offset()));
__ AddImmediate(kCacheArrayReg,
target::Array::data_offset() - kHeapObjectTag);
Label loop, not_closure;
if (n >= 5) {
__ LoadClassIdMayBeSmi(STCInternalRegs::kInstanceCidOrSignatureReg,
TypeTestABI::TypeTestABI::kInstanceReg);
} else {
__ LoadClassId(STCInternalRegs::kInstanceCidOrSignatureReg,
TypeTestABI::kInstanceReg);
}
__ CompareImmediate(STCInternalRegs::kInstanceCidOrSignatureReg, kClosureCid);
__ BranchIf(NE, &not_closure);
// Closure handling.
{
__ Comment("Closure");
__ LoadCompressed(STCInternalRegs::kInstanceCidOrSignatureReg,
FieldAddress(TypeTestABI::kInstanceReg,
target::Closure::function_offset()));
__ LoadCompressed(STCInternalRegs::kInstanceCidOrSignatureReg,
FieldAddress(STCInternalRegs::kInstanceCidOrSignatureReg,
target::Function::signature_offset()));
if (n >= 3) {
__ LoadCompressed(
STCInternalRegs::kInstanceInstantiatorTypeArgumentsReg,
FieldAddress(TypeTestABI::kInstanceReg,
target::Closure::instantiator_type_arguments_offset()));
if (n >= 7) {
__ LoadCompressed(
STCInternalRegs::kInstanceParentFunctionTypeArgumentsReg,
FieldAddress(TypeTestABI::kInstanceReg,
target::Closure::function_type_arguments_offset()));
__ LoadCompressed(
STCInternalRegs::kInstanceDelayedFunctionTypeArgumentsReg,
FieldAddress(TypeTestABI::kInstanceReg,
target::Closure::delayed_type_arguments_offset()));
}
}
__ j(&loop);
}
// Non-Closure handling.
{
__ Comment("Non-Closure");
__ Bind(&not_closure);
if (n >= 3) {
Label has_no_type_arguments;
__ LoadClassById(kScratchReg,
STCInternalRegs::kInstanceCidOrSignatureReg);
__ mv(STCInternalRegs::kInstanceInstantiatorTypeArgumentsReg, kNullReg);
__ LoadFieldFromOffset(
kScratchReg, kScratchReg,
target::Class::host_type_arguments_field_offset_in_words_offset(),
kFourBytes);
__ CompareImmediate(kScratchReg, target::Class::kNoTypeArguments);
__ BranchIf(EQ, &has_no_type_arguments);
__ slli(kScratchReg, kScratchReg, kCompressedWordSizeLog2);
__ add(kScratchReg, kScratchReg, TypeTestABI::kInstanceReg);
__ LoadCompressed(STCInternalRegs::kInstanceInstantiatorTypeArgumentsReg,
FieldAddress(kScratchReg, 0));
__ Bind(&has_no_type_arguments);
__ Comment("No type arguments");
if (n >= 7) {
__ mv(STCInternalRegs::kInstanceParentFunctionTypeArgumentsReg,
kNullReg);
__ mv(STCInternalRegs::kInstanceDelayedFunctionTypeArgumentsReg,
kNullReg);
}
}
__ SmiTag(STCInternalRegs::kInstanceCidOrSignatureReg);
}
Label found, done, next_iteration;
// Loop header
__ Bind(&loop);
__ Comment("Loop");
__ LoadCompressed(
kScratchReg,
Address(kCacheArrayReg,
target::kCompressedWordSize *
target::SubtypeTestCache::kInstanceCidOrSignature));
__ CompareObjectRegisters(kScratchReg, kNullReg);
__ BranchIf(EQ, &done);
__ CompareObjectRegisters(kScratchReg,
STCInternalRegs::kInstanceCidOrSignatureReg);
if (n == 1) {
__ BranchIf(EQ, &found);
} else {
__ BranchIf(NE, &next_iteration);
__ LoadCompressed(kScratchReg,
Address(kCacheArrayReg,
target::kCompressedWordSize *
target::SubtypeTestCache::kDestinationType));
__ CompareRegisters(kScratchReg, TypeTestABI::kDstTypeReg);
__ BranchIf(NE, &next_iteration);
__ LoadCompressed(
kScratchReg,
Address(kCacheArrayReg,
target::kCompressedWordSize *
target::SubtypeTestCache::kInstanceTypeArguments));
__ CompareRegisters(kScratchReg,
STCInternalRegs::kInstanceInstantiatorTypeArgumentsReg);
if (n == 3) {
__ BranchIf(EQ, &found);
} else {
__ BranchIf(NE, &next_iteration);
__ LoadCompressed(
kScratchReg,
Address(kCacheArrayReg,
target::kCompressedWordSize *
target::SubtypeTestCache::kInstantiatorTypeArguments));
__ CompareRegisters(kScratchReg,
TypeTestABI::kInstantiatorTypeArgumentsReg);
__ BranchIf(NE, &next_iteration);
__ LoadCompressed(
kScratchReg,
Address(kCacheArrayReg,
target::kCompressedWordSize *
target::SubtypeTestCache::kFunctionTypeArguments));
__ CompareRegisters(kScratchReg, TypeTestABI::kFunctionTypeArgumentsReg);
if (n == 5) {
__ BranchIf(EQ, &found);
} else {
ASSERT(n == 7);
__ BranchIf(NE, &next_iteration);
__ LoadCompressed(
kScratchReg, Address(kCacheArrayReg,
target::kCompressedWordSize *
target::SubtypeTestCache::
kInstanceParentFunctionTypeArguments));
__ CompareRegisters(
kScratchReg,
STCInternalRegs::kInstanceParentFunctionTypeArgumentsReg);
__ BranchIf(NE, &next_iteration);
__ LoadCompressed(
kScratchReg,
Address(kCacheArrayReg,
target::kCompressedWordSize *
target::SubtypeTestCache::
kInstanceDelayedFunctionTypeArguments));
__ CompareRegisters(
kScratchReg,
STCInternalRegs::kInstanceDelayedFunctionTypeArgumentsReg);
__ BranchIf(EQ, &found);
}
}
}
__ Bind(&next_iteration);
__ Comment("Next iteration");
__ AddImmediate(
kCacheArrayReg,
target::kCompressedWordSize * target::SubtypeTestCache::kTestEntryLength);
__ j(&loop);
__ Bind(&found);
__ Comment("Found");
__ LoadCompressed(
TypeTestABI::kSubtypeTestCacheResultReg,
Address(kCacheArrayReg, target::kCompressedWordSize *
target::SubtypeTestCache::kTestResult));
__ Bind(&done);
__ Comment("Done");
__ ret();
}
// See comment on [GenerateSubtypeNTestCacheStub].
void StubCodeCompiler::GenerateSubtype1TestCacheStub(Assembler* assembler) {
GenerateSubtypeNTestCacheStub(assembler, 1);
}
// See comment on [GenerateSubtypeNTestCacheStub].
void StubCodeCompiler::GenerateSubtype3TestCacheStub(Assembler* assembler) {
GenerateSubtypeNTestCacheStub(assembler, 3);
}
// See comment on [GenerateSubtypeNTestCacheStub].
void StubCodeCompiler::GenerateSubtype5TestCacheStub(Assembler* assembler) {
GenerateSubtypeNTestCacheStub(assembler, 5);
}
// See comment on [GenerateSubtypeNTestCacheStub].
void StubCodeCompiler::GenerateSubtype7TestCacheStub(Assembler* assembler) {
GenerateSubtypeNTestCacheStub(assembler, 7);
}
void StubCodeCompiler::GenerateGetCStackPointerStub(Assembler* assembler) {
__ mv(A0, SP);
__ ret();
}
// Jump to a frame on the call stack.
// RA: return address.
// A0: program_counter.
// A1: stack_pointer.
// A2: frame_pointer.
// A3: thread.
// Does not return.
//
// Notice: We need to keep this in sync with `Simulator::JumpToFrame()`.
void StubCodeCompiler::GenerateJumpToFrameStub(Assembler* assembler) {
ASSERT(kExceptionObjectReg == A0);
ASSERT(kStackTraceObjectReg == A1);
__ mv(CALLEE_SAVED_TEMP, A0); // Program counter.
__ mv(SP, A1); // Stack pointer.
__ mv(FP, A2); // Frame_pointer.
__ mv(THR, A3);
#if defined(DART_TARGET_OS_FUCHSIA)
__ lx(S2, Address(THR, target::Thread::saved_shadow_call_stack_offset()));
#elif defined(USING_SHADOW_CALL_STACK)
#error Unimplemented
#endif
Label exit_through_non_ffi;
// 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 TransititionGeneratedToVM/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(TMP, THR,
compiler::target::Thread::exit_through_ffi_offset());
__ LoadImmediate(TMP2, target::Thread::exit_through_ffi());
__ bne(TMP, TMP2, &exit_through_non_ffi);
__ TransitionNativeToGenerated(TMP, /*leave_safepoint=*/true,
/*ignore_unwind_in_progress=*/true);
__ Bind(&exit_through_non_ffi);
// Refresh pinned registers values (inc. write barrier mask and null object).
__ RestorePinnedRegisters();
// Set the tag.
__ LoadImmediate(TMP, VMTag::kDartTagId);
__ StoreToOffset(TMP, THR, target::Thread::vm_tag_offset());
// Clear top exit frame.
__ StoreToOffset(ZR, THR, target::Thread::top_exit_frame_info_offset());
// Restore the pool pointer.
__ RestoreCodePointer();
if (FLAG_precompiled_mode) {
__ SetupGlobalPoolAndDispatchTable();
} else {
__ LoadPoolPointer();
}
__ jr(CALLEE_SAVED_TEMP); // 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.
void StubCodeCompiler::GenerateRunExceptionHandlerStub(Assembler* assembler) {
// Exception object.
ASSERT(kExceptionObjectReg == A0);
__ LoadFromOffset(A0, THR, target::Thread::active_exception_offset());
__ StoreToOffset(NULL_REG, THR, target::Thread::active_exception_offset());
// StackTrace object.
ASSERT(kStackTraceObjectReg == A1);
__ LoadFromOffset(A1, THR, target::Thread::active_stacktrace_offset());
__ StoreToOffset(NULL_REG, THR, target::Thread::active_stacktrace_offset());
__ LoadFromOffset(RA, THR, target::Thread::resume_pc_offset());
__ ret(); // Jump to the exception handler code.
}
// Deoptimize a frame on the call stack before rewinding.
// The arguments are stored in the Thread object.
// No result.
void StubCodeCompiler::GenerateDeoptForRewindStub(Assembler* assembler) {
// Push zap value instead of CODE_REG.
__ LoadImmediate(TMP, kZapCodeReg);
__ PushRegister(TMP);
// Load the deopt pc into RA.
__ LoadFromOffset(RA, THR, target::Thread::resume_pc_offset());
GenerateDeoptimizationSequence(assembler, kEagerDeopt);
// After we have deoptimized, jump to the correct frame.
__ EnterStubFrame();
__ CallRuntime(kRewindPostDeoptRuntimeEntry, 0);
__ LeaveStubFrame();
__ ebreak();
}
// Calls to the runtime to optimize the given function.
// A0: function to be re-optimized.
// ARGS_DESC_REG: argument descriptor (preserved).
void StubCodeCompiler::GenerateOptimizeFunctionStub(Assembler* assembler) {
__ LoadFromOffset(CODE_REG, THR, target::Thread::optimize_stub_offset());
__ EnterStubFrame();
__ subi(SP, SP, 3 * target::kWordSize);
__ sx(ARGS_DESC_REG,
Address(SP, 2 * target::kWordSize)); // Preserves args descriptor.
__ sx(ZR, Address(SP, 1 * target::kWordSize)); // Result slot.
__ sx(A0, Address(SP, 0 * target::kWordSize)); // Function argument.
__ CallRuntime(kOptimizeInvokedFunctionRuntimeEntry, 1);
__ lx(FUNCTION_REG, Address(SP, 1 * target::kWordSize)); // Function result.
__ lx(ARGS_DESC_REG,
Address(SP, 2 * target::kWordSize)); // Restore args descriptor.
__ addi(SP, SP, 3 * target::kWordSize);
__ LoadCompressedFieldFromOffset(CODE_REG, FUNCTION_REG,
target::Function::code_offset());
__ LoadFieldFromOffset(A1, FUNCTION_REG,
target::Function::entry_point_offset());
__ LeaveStubFrame();
__ jr(A1);
__ ebreak();
}
// Does identical check (object references are equal or not equal) with special
// checks for boxed numbers and returns with TMP = 0 iff left and right are
// identical.
static void GenerateIdenticalWithNumberCheckStub(Assembler* assembler,
const Register left,
const Register right) {
Label reference_compare, check_mint, done;
// If any of the arguments is Smi do reference compare.
// Note: A Mint cannot contain a value that would fit in Smi.
__ BranchIfSmi(left, &reference_compare, Assembler::kNearJump);
__ BranchIfSmi(right, &reference_compare, Assembler::kNearJump);
// Value compare for two doubles.
__ CompareClassId(left, kDoubleCid, /*scratch*/ TMP);
__ BranchIf(NOT_EQUAL, &check_mint, Assembler::kNearJump);
__ CompareClassId(right, kDoubleCid, /*scratch*/ TMP);
__ BranchIf(NOT_EQUAL, &reference_compare, Assembler::kNearJump);
// Double values bitwise compare.
#if XLEN == 32
__ lw(T0, FieldAddress(left, target::Double::value_offset()));
__ lw(T1, FieldAddress(right, target::Double::value_offset()));
__ xor_(TMP, T0, T1);
__ lw(T0, FieldAddress(left, target::Double::value_offset() + 4));
__ lw(T1, FieldAddress(right, target::Double::value_offset() + 4));
__ xor_(TMP2, T0, T1);
__ or_(TMP, TMP, TMP2);
#else
__ ld(T0, FieldAddress(left, target::Double::value_offset()));
__ ld(T1, FieldAddress(right, target::Double::value_offset()));
__ xor_(TMP, T0, T1);
#endif
__ j(&done, Assembler::kNearJump);
__ Bind(&check_mint);
__ CompareClassId(left, kMintCid, /*scratch*/ TMP);
__ BranchIf(NOT_EQUAL, &reference_compare, Assembler::kNearJump);
__ CompareClassId(right, kMintCid, /*scratch*/ TMP);
__ BranchIf(NOT_EQUAL, &reference_compare, Assembler::kNearJump);
#if XLEN == 32
__ lw(T0, FieldAddress(left, target::Mint::value_offset()));
__ lw(T1, FieldAddress(right, target::Mint::value_offset()));
__ xor_(TMP, T0, T1);
__ lw(T0, FieldAddress(left, target::Mint::value_offset() + 4));
__ lw(T1, FieldAddress(right, target::Mint::value_offset() + 4));
__ xor_(TMP2, T0, T1);
__ or_(TMP, TMP, TMP2);
#else
__ ld(T0, FieldAddress(left, target::Mint::value_offset()));
__ ld(T1, FieldAddress(right, target::Mint::value_offset()));
__ xor_(TMP, T0, T1);
#endif
__ j(&done, Assembler::kNearJump);
__ Bind(&reference_compare);
__ xor_(TMP, left, right);
__ Bind(&done);
}
// Called only from unoptimized code. All relevant registers have been saved.
// RA: return address.
// SP + 4: left operand.
// SP + 0: right operand.
// Return TMP set to 0 if equal.
void StubCodeCompiler::GenerateUnoptimizedIdenticalWithNumberCheckStub(
Assembler* assembler) {
#if !defined(PRODUCT)
// Check single stepping.
Label stepping, done_stepping;
__ LoadIsolate(TMP);
__ LoadFromOffset(TMP, TMP, target::Isolate::single_step_offset(),
kUnsignedByte);
__ bnez(TMP, &stepping);
__ Bind(&done_stepping);
#endif
const Register left = A0;
const Register right = A1;
__ LoadFromOffset(left, SP, 1 * target::kWordSize);
__ LoadFromOffset(right, SP, 0 * target::kWordSize);
GenerateIdenticalWithNumberCheckStub(assembler, left, right);
__ ret();
#if !defined(PRODUCT)
__ Bind(&stepping);
__ EnterStubFrame();
__ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
__ RestoreCodePointer();
__ LeaveStubFrame();
__ j(&done_stepping);
#endif
}
// Called from optimized code only.
// RA: return address.
// SP + 4: left operand.
// SP + 0: right operand.
// Return TMP set to 0 if equal.
void StubCodeCompiler::GenerateOptimizedIdenticalWithNumberCheckStub(
Assembler* assembler) {
const Register left = A0;
const Register right = A1;
__ LoadFromOffset(left, SP, 1 * target::kWordSize);
__ LoadFromOffset(right, SP, 0 * target::kWordSize);
GenerateIdenticalWithNumberCheckStub(assembler, left, right);
__ ret();
}
// Called from megamorphic call sites.
// A0: receiver (passed to target)
// IC_DATA_REG: MegamorphicCache (preserved)
// Passed to target:
// FUNCTION_REG: target function
// CODE_REG: target Code
// ARGS_DESC_REG: arguments descriptor
void StubCodeCompiler::GenerateMegamorphicCallStub(Assembler* assembler) {
// Jump if receiver is a smi.
Label smi_case;
__ BranchIfSmi(A0, &smi_case);
// Loads the cid of the object.
__ LoadClassId(T5, A0);
Label cid_loaded;
__ Bind(&cid_loaded);
__ lx(T2,
FieldAddress(IC_DATA_REG, target::MegamorphicCache::buckets_offset()));
__ lx(T1, FieldAddress(IC_DATA_REG, target::MegamorphicCache::mask_offset()));
// T2: cache buckets array.
// T1: mask as a smi.
// Make the cid into a smi.
__ SmiTag(T5);
// T5: class ID of the receiver (smi).
// Compute the table index.
ASSERT(target::MegamorphicCache::kSpreadFactor == 7);
// Use lsl and sub to multiply with 7 == 8 - 1.
__ slli(T3, T5, 3);
__ sub(T3, T3, T5);
// T3: probe.
Label loop;
__ Bind(&loop);
__ and_(T3, T3, T1);
const intptr_t base = target::Array::data_offset();
// T3 is smi tagged, but table entries are 16 bytes, so LSL 3.
__ slli(TMP, T3, kCompressedWordSizeLog2);
__ add(TMP, TMP, T2);
__ LoadCompressedSmiFieldFromOffset(T4, TMP, base);
Label probe_failed;
__ CompareObjectRegisters(T4, T5);
__ BranchIf(NE, &probe_failed);
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.
__ LoadCompressed(FUNCTION_REG,
FieldAddress(TMP, base + target::kCompressedWordSize));
__ lx(A1, FieldAddress(FUNCTION_REG, target::Function::entry_point_offset()));
__ lx(ARGS_DESC_REG,
FieldAddress(IC_DATA_REG,
target::CallSiteData::arguments_descriptor_offset()));
if (!FLAG_precompiled_mode) {
__ LoadCompressed(
CODE_REG, FieldAddress(FUNCTION_REG, target::Function::code_offset()));
}
__ jr(A1); // T0: Function, argument to lazy compile stub.
// Probe failed, check if it is a miss.
__ Bind(&probe_failed);
ASSERT(kIllegalCid == 0);
Label miss;
__ beqz(T4, &miss); // branch if miss.
// Try next extry in the table.
__ AddImmediate(T3, target::ToRawSmi(1));
__ j(&loop);
// Load cid for the Smi case.
__ Bind(&smi_case);
__ LoadImmediate(T5, kSmiCid);
__ j(&cid_loaded);
__ Bind(&miss);
GenerateSwitchableCallMissStub(assembler);
}
// Input:
// A0 - receiver
// IC_DATA_REG - icdata
void StubCodeCompiler::GenerateICCallThroughCodeStub(Assembler* assembler) {
Label loop, found, miss;
__ lx(T1, FieldAddress(IC_DATA_REG, target::ICData::entries_offset()));
__ lx(ARGS_DESC_REG,
FieldAddress(IC_DATA_REG,
target::CallSiteData::arguments_descriptor_offset()));
__ AddImmediate(T1, target::Array::data_offset() - kHeapObjectTag);
// T1: first IC entry
__ LoadTaggedClassIdMayBeSmi(A1, A0);
// A1: receiver cid as Smi
__ Bind(&loop);
__ LoadCompressedSmi(T2, Address(T1, 0));
__ beq(A1, T2, &found);
__ CompareImmediate(T2, target::ToRawSmi(kIllegalCid));
__ BranchIf(EQ, &miss);
const intptr_t entry_length =
target::ICData::TestEntryLengthFor(1, /*tracking_exactness=*/false) *
target::kCompressedWordSize;
__ AddImmediate(T1, entry_length); // Next entry.
__ j(&loop);
__ Bind(&found);
if (FLAG_precompiled_mode) {
const intptr_t entry_offset =
target::ICData::EntryPointIndexFor(1) * target::kCompressedWordSize;
__ LoadCompressed(A1, Address(T1, entry_offset));
__ lx(A1, FieldAddress(A1, target::Function::entry_point_offset()));
} else {
const intptr_t code_offset =
target::ICData::CodeIndexFor(1) * target::kCompressedWordSize;
__ LoadCompressed(CODE_REG, Address(T1, code_offset));
__ lx(A1, FieldAddress(CODE_REG, target::Code::entry_point_offset()));
}
__ jr(A1);
__ Bind(&miss);
__ LoadIsolate(A1);
__ lx(CODE_REG, Address(A1, target::Isolate::ic_miss_code_offset()));
__ lx(A1, FieldAddress(CODE_REG, target::Code::entry_point_offset()));
__ jr(A1);
}
// Implement the monomorphic entry check for call-sites where the receiver
// might be a Smi.
//
// A0: receiver
// S5: MonomorphicSmiableCall object
//
// T1,T2: clobbered
void StubCodeCompiler::GenerateMonomorphicSmiableCheckStub(
Assembler* assembler) {
Label miss;
__ LoadClassIdMayBeSmi(T1, A0);
// Note: this stub is only used in AOT mode, hence the direct (bare) call.
__ LoadField(
T2,
FieldAddress(S5, target::MonomorphicSmiableCall::expected_cid_offset()));
__ LoadField(
TMP,
FieldAddress(S5, target::MonomorphicSmiableCall::entrypoint_offset()));
__ bne(T1, T2, &miss);
__ jr(TMP);
__ Bind(&miss);
__ lx(TMP, Address(THR, target::Thread::switchable_call_miss_entry_offset()));
__ jr(TMP);
}
// Called from switchable IC calls.
// A0: receiver
void StubCodeCompiler::GenerateSwitchableCallMissStub(Assembler* assembler) {
__ lx(CODE_REG,
Address(THR, target::Thread::switchable_call_miss_stub_offset()));
__ EnterStubFrame();
// Preserve receiver, setup result slot,
// pass Arg0: stub out and Arg1: Receiver.
__ PushRegistersInOrder({A0, ZR, ZR, A0});
__ CallRuntime(kSwitchableCallMissRuntimeEntry, 2);
__ Drop(1);
__ PopRegister(CODE_REG); // result = stub
__ PopRegister(IC_DATA_REG); // result = IC
__ PopRegister(A0); // Restore receiver.
__ LeaveStubFrame();
__ lx(TMP, FieldAddress(CODE_REG, target::Code::entry_point_offset(
CodeEntryKind::kNormal)));
__ jr(TMP);
}
// Called from switchable IC calls.
// A0: receiver
// S5: SingleTargetCache
// Passed to target:
// CODE_REG: target Code object
void StubCodeCompiler::GenerateSingleTargetCallStub(Assembler* assembler) {
Label miss;
__ LoadClassIdMayBeSmi(A1, A0);
__ lhu(T2, FieldAddress(S5, target::SingleTargetCache::lower_limit_offset()));
__ lhu(T3, FieldAddress(S5, target::SingleTargetCache::upper_limit_offset()));
__ blt(A1, T2, &miss);
__ bgt(A1, T3, &miss);
__ lx(TMP, FieldAddress(S5, target::SingleTargetCache::entry_point_offset()));
__ lx(CODE_REG, FieldAddress(S5, target::SingleTargetCache::target_offset()));
__ jr(TMP);
__ Bind(&miss);
__ EnterStubFrame();
// Preserve receiver, setup result slot,
// pass Arg0: Stub out and Arg1: Receiver.
__ PushRegistersInOrder({A0, ZR, ZR, A0});
__ CallRuntime(kSwitchableCallMissRuntimeEntry, 2);
__ Drop(1);
__ PopRegister(CODE_REG); // result = stub
__ PopRegister(S5); // result = IC
__ PopRegister(A0); // Restore receiver.
__ LeaveStubFrame();
__ lx(TMP, FieldAddress(CODE_REG, target::Code::entry_point_offset(
CodeEntryKind::kMonomorphic)));
__ jr(TMP);
}
// Instantiate type arguments from instantiator and function type args.
// T1 uninstantiated type arguments.
// T2 instantiator type arguments.
// T3: function type arguments.
// Returns instantiated type arguments in T5.
void StubCodeCompiler::GenerateInstantiateTypeArgumentsStub(
Assembler* assembler) {
// Lookup cache before calling runtime.
__ LoadCompressedFieldFromOffset(
A1, InstantiationABI::kUninstantiatedTypeArgumentsReg,
target::TypeArguments::instantiations_offset());
__ AddImmediate(A1, Array::data_offset() - kHeapObjectTag);
// The instantiations cache is initialized with Object::zero_array() and is
// therefore guaranteed to contain kNoInstantiator. No length check needed.
compiler::Label loop, next, found, call_runtime;
__ Bind(&loop);
// Use load-acquire to test for sentinel, if we found non-sentinel it is safe
// to access the other entries. If we found a sentinel we go to runtime.
__ LoadAcquireCompressed(
A6, A1,
TypeArguments::Instantiation::kInstantiatorTypeArgsIndex *
target::kCompressedWordSize);
__ CompareImmediate(A6, Smi::RawValue(TypeArguments::kNoInstantiator),
kObjectBytes);
__ BranchIf(EQ, &call_runtime);
__ CompareRegisters(A6, InstantiationABI::kInstantiatorTypeArgumentsReg);
__ BranchIf(NE, &next);
__ LoadCompressedFromOffset(
A7, A1,
TypeArguments::Instantiation::kFunctionTypeArgsIndex *
target::kCompressedWordSize);
__ CompareRegisters(A7, InstantiationABI::kFunctionTypeArgumentsReg);
__ BranchIf(EQ, &found);
__ Bind(&next);
__ AddImmediate(A1, TypeArguments::Instantiation::kSizeInWords *
target::kCompressedWordSize);
__ j(&loop);
// Instantiate non-null type arguments.
// A runtime call to instantiate the type arguments is required.
__ Bind(&call_runtime);
__ EnterStubFrame();
__ PushRegistersInOrder({NULL_REG,
InstantiationABI::kUninstantiatedTypeArgumentsReg,
InstantiationABI::kInstantiatorTypeArgumentsReg,
InstantiationABI::kFunctionTypeArgumentsReg});
__ CallRuntime(kInstantiateTypeArgumentsRuntimeEntry, 3);
__ Drop(3); // Drop 2 type vectors, and uninstantiated type.
__ PopRegister(InstantiationABI::kResultTypeArgumentsReg);
__ LeaveStubFrame();
__ Ret();
__ Bind(&found);
__ LoadCompressedFromOffset(
InstantiationABI::kResultTypeArgumentsReg, A1,
TypeArguments::Instantiation::kInstantiatedTypeArgsIndex *
target::kCompressedWordSize);
__ Ret();
}
void StubCodeCompiler::
GenerateInstantiateTypeArgumentsMayShareInstantiatorTAStub(
Assembler* assembler) {
// Return the instantiator type arguments if its nullability is compatible for
// sharing, otherwise proceed to instantiation cache lookup.
compiler::Label cache_lookup;
__ LoadCompressedSmi(
A6, FieldAddress(InstantiationABI::kUninstantiatedTypeArgumentsReg,
target::TypeArguments::nullability_offset()));
__ LoadCompressedSmi(
A7, FieldAddress(InstantiationABI::kInstantiatorTypeArgumentsReg,
target::TypeArguments::nullability_offset()));
__ and_(A7, A7, A6);
__ CompareRegisters(A7, A6);
__ BranchIf(NE, &cache_lookup);
__ mv(InstantiationABI::kResultTypeArgumentsReg,
InstantiationABI::kInstantiatorTypeArgumentsReg);
__ Ret();
__ Bind(&cache_lookup);
GenerateInstantiateTypeArgumentsStub(assembler);
}
void StubCodeCompiler::GenerateInstantiateTypeArgumentsMayShareFunctionTAStub(
Assembler* assembler) {
// Return the function type arguments if its nullability is compatible for
// sharing, otherwise proceed to instantiation cache lookup.
compiler::Label cache_lookup;
__ LoadCompressedSmi(
A6, FieldAddress(InstantiationABI::kUninstantiatedTypeArgumentsReg,
target::TypeArguments::nullability_offset()));
__ LoadCompressedSmi(
A7, FieldAddress(InstantiationABI::kFunctionTypeArgumentsReg,
target::TypeArguments::nullability_offset()));
__ and_(A7, A7, A6);
__ CompareRegisters(A7, A6);
__ BranchIf(NE, &cache_lookup);
__ mv(InstantiationABI::kResultTypeArgumentsReg,
InstantiationABI::kFunctionTypeArgumentsReg);
__ Ret();
__ Bind(&cache_lookup);
GenerateInstantiateTypeArgumentsStub(assembler);
}
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(Assembler* assembler,
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 == T2);
COMPILE_ASSERT(AllocateTypedDataArrayABI::kResultReg == A0);
if (!FLAG_use_slow_path && FLAG_inline_alloc) {
Label call_runtime;
NOT_IN_PRODUCT(__ MaybeTraceAllocation(cid, &call_runtime, T3));
__ mv(T3, AllocateTypedDataArrayABI::kLengthReg);
/* Check that length is a positive Smi. */
/* T3: requested array length argument. */
__ BranchIfNotSmi(T3, &call_runtime);
__ SmiUntag(T3);
/* Check for length >= 0 && length <= max_len. */
/* T3: untagged array length. */
__ CompareImmediate(T3, max_len, kObjectBytes);
__ BranchIf(UNSIGNED_GREATER, &call_runtime);
if (scale_shift != 0) {
__ slli(T3, T3, scale_shift);
}
const intptr_t fixed_size_plus_alignment_padding =
target::TypedData::HeaderSize() +
target::ObjectAlignment::kObjectAlignment - 1;
__ AddImmediate(T3, fixed_size_plus_alignment_padding);
__ andi(T3, T3, ~(target::ObjectAlignment::kObjectAlignment - 1));
__ lx(A0, Address(THR, target::Thread::top_offset()));
/* T3: allocation size. */
__ add(T4, A0, T3);
__ bltu(T4, A0, &call_runtime); /* Fail on unsigned overflow. */
/* Check if the allocation fits into the remaining space. */
/* A0: potential new object start. */
/* T4: potential next object start. */
/* T3: allocation size. */
__ lx(TMP, Address(THR, target::Thread::end_offset()));
__ bgeu(T4, TMP, &call_runtime);
/* Successfully allocated the object(s), now update top to point to */
/* next object start and initialize the object. */
__ sx(T4, Address(THR, target::Thread::top_offset()));
__ AddImmediate(A0, kHeapObjectTag);
/* Initialize the tags. */
/* A0: new object start as a tagged pointer. */
/* T4: new object end address. */
/* T3: allocation size. */
{
__ li(T5, 0);
__ CompareImmediate(T3, target::UntaggedObject::kSizeTagMaxSizeTag);
compiler::Label zero_tags;
__ BranchIf(HI, &zero_tags);
__ slli(T5, T3,
target::UntaggedObject::kTagBitsSizeTagPos -
target::ObjectAlignment::kObjectAlignmentLog2);
__ Bind(&zero_tags);
/* Get the class index and insert it into the tags. */
uword tags =
target::MakeTagWordForNewSpaceObject(cid, /*instance_size=*/0);
__ OrImmediate(T5, T5, tags);
__ sx(T5, FieldAddress(A0, target::Object::tags_offset())); /* Tags. */
}
/* Set the length field. */
/* A0: new object start as a tagged pointer. */
/* T4: new object end address. */
__ mv(T3, AllocateTypedDataArrayABI::kLengthReg); /* Array length. */
__ StoreCompressedIntoObjectNoBarrier(
A0, FieldAddress(A0, target::TypedDataBase::length_offset()), T3);
/* Initialize all array elements to 0. */
/* A0: new object start as a tagged pointer. */
/* T4: new object end address. */
/* T3: iterator which initially points to the start of the variable */
/* R3: scratch register. */
/* data area to be initialized. */
__ AddImmediate(T3, A0, target::TypedData::HeaderSize() - 1);
__ StoreInternalPointer(
A0, FieldAddress(A0, target::PointerBase::data_offset()), T3);
Label loop;
__ Bind(&loop);
for (intptr_t offset = 0; offset < target::kObjectAlignment;
offset += target::kWordSize) {
__ sx(ZR, Address(T3, offset));
}
// Safe to only check every kObjectAlignment bytes instead of each word.
ASSERT(kAllocationRedZoneSize >= target::kObjectAlignment);
__ addi(T3, T3, target::kObjectAlignment);
__ bltu(T3, T4, &loop);
__ Ret();
__ Bind(&call_runtime);
}
__ EnterStubFrame();
__ PushRegister(ZR); // Result slot.
__ PushImmediate(target::ToRawSmi(cid)); // Cid
__ PushRegister(AllocateTypedDataArrayABI::kLengthReg); // Array length
__ CallRuntime(kAllocateTypedDataRuntimeEntry, 2);
__ Drop(2); // Drop arguments.
__ PopRegister(AllocateTypedDataArrayABI::kResultReg);
__ LeaveStubFrame();
__ Ret();
}
} // namespace compiler
} // namespace dart
#endif // defined(TARGET_ARCH_RISCV)
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