// Copyright 2013 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#if V8_TARGET_ARCH_ARM64
#include "src/api-arguments.h"
#include "src/arm64/assembler-arm64-inl.h"
#include "src/arm64/macro-assembler-arm64-inl.h"
#include "src/bootstrapper.h"
#include "src/code-stubs.h"
#include "src/counters.h"
#include "src/frame-constants.h"
#include "src/frames.h"
#include "src/heap/heap-inl.h"
#include "src/ic/ic.h"
#include "src/ic/stub-cache.h"
#include "src/isolate.h"
#include "src/objects/api-callbacks.h"
#include "src/objects/regexp-match-info.h"
#include "src/regexp/jsregexp.h"
#include "src/regexp/regexp-macro-assembler.h"
#include "src/runtime/runtime.h"
#include "src/arm64/code-stubs-arm64.h" // Cannot be the first include.
namespace v8 {
namespace internal {
#define __ ACCESS_MASM(masm)
// This is the entry point from C++. 5 arguments are provided in x0-x4.
// See use of the JSEntryFunction for example in src/execution.cc.
// Input:
// x0: code entry.
// x1: function.
// x2: receiver.
// x3: argc.
// x4: argv.
// Output:
// x0: result.
void JSEntryStub::Generate(MacroAssembler* masm) {
Label invoke, handler_entry, exit;
Register code_entry = x0;
{
NoRootArrayScope no_root_array(masm);
// Enable instruction instrumentation. This only works on the simulator, and
// will have no effect on the model or real hardware.
__ EnableInstrumentation();
__ PushCalleeSavedRegisters();
ProfileEntryHookStub::MaybeCallEntryHook(masm);
// Set up the reserved register for 0.0.
__ Fmov(fp_zero, 0.0);
// Initialize the root array register
__ InitializeRootRegister();
}
// Build an entry frame (see layout below).
StackFrame::Type marker = type();
int64_t bad_frame_pointer = -1L; // Bad frame pointer to fail if it is used.
__ Mov(x13, bad_frame_pointer);
__ Mov(x12, StackFrame::TypeToMarker(marker));
__ Mov(x11, ExternalReference::Create(IsolateAddressId::kCEntryFPAddress,
isolate()));
__ Ldr(x10, MemOperand(x11));
__ Push(x13, x12, xzr, x10);
// Set up fp.
__ Sub(fp, sp, EntryFrameConstants::kCallerFPOffset);
// Push the JS entry frame marker. Also set js_entry_sp if this is the
// outermost JS call.
Label non_outermost_js, done;
ExternalReference js_entry_sp =
ExternalReference::Create(IsolateAddressId::kJSEntrySPAddress, isolate());
__ Mov(x10, js_entry_sp);
__ Ldr(x11, MemOperand(x10));
// Select between the inner and outermost frame marker, based on the JS entry
// sp. We assert that the inner marker is zero, so we can use xzr to save a
// move instruction.
DCHECK_EQ(StackFrame::INNER_JSENTRY_FRAME, 0);
__ Cmp(x11, 0); // If x11 is zero, this is the outermost frame.
__ Csel(x12, xzr, StackFrame::OUTERMOST_JSENTRY_FRAME, ne);
__ B(ne, &done);
__ Str(fp, MemOperand(x10));
__ Bind(&done);
__ Push(x12, padreg);
// The frame set up looks like this:
// sp[0] : padding.
// sp[1] : JS entry frame marker.
// sp[2] : C entry FP.
// sp[3] : stack frame marker.
// sp[4] : stack frame marker.
// sp[5] : bad frame pointer 0xFFF...FF <- fp points here.
// Jump to a faked try block that does the invoke, with a faked catch
// block that sets the pending exception.
__ B(&invoke);
// Prevent the constant pool from being emitted between the record of the
// handler_entry position and the first instruction of the sequence here.
// There is no risk because Assembler::Emit() emits the instruction before
// checking for constant pool emission, but we do not want to depend on
// that.
{
Assembler::BlockPoolsScope block_pools(masm);
__ bind(&handler_entry);
handler_offset_ = handler_entry.pos();
// Caught exception: Store result (exception) in the pending exception
// field in the JSEnv and return a failure sentinel. Coming in here the
// fp will be invalid because the PushTryHandler below sets it to 0 to
// signal the existence of the JSEntry frame.
__ Mov(x10, Operand(ExternalReference::Create(
IsolateAddressId::kPendingExceptionAddress, isolate())));
}
__ Str(code_entry, MemOperand(x10));
__ LoadRoot(x0, Heap::kExceptionRootIndex);
__ B(&exit);
// Invoke: Link this frame into the handler chain.
__ Bind(&invoke);
// Push new stack handler.
static_assert(StackHandlerConstants::kSize == 2 * kPointerSize,
"Unexpected offset for StackHandlerConstants::kSize");
static_assert(StackHandlerConstants::kNextOffset == 0 * kPointerSize,
"Unexpected offset for StackHandlerConstants::kNextOffset");
// Link the current handler as the next handler.
__ Mov(x11, ExternalReference::Create(IsolateAddressId::kHandlerAddress,
isolate()));
__ Ldr(x10, MemOperand(x11));
__ Push(padreg, x10);
// Set this new handler as the current one.
{
UseScratchRegisterScope temps(masm);
Register scratch = temps.AcquireX();
__ Mov(scratch, sp);
__ Str(scratch, MemOperand(x11));
}
// If an exception not caught by another handler occurs, this handler
// returns control to the code after the B(&invoke) above, which
// restores all callee-saved registers (including cp and fp) to their
// saved values before returning a failure to C.
// Invoke the function by calling through the JS entry trampoline builtin.
// Notice that we cannot store a reference to the trampoline code directly in
// this stub, because runtime stubs are not traversed when doing GC.
// Expected registers by Builtins::JSEntryTrampoline
// x0: code entry.
// x1: function.
// x2: receiver.
// x3: argc.
// x4: argv.
__ Call(EntryTrampoline(), RelocInfo::CODE_TARGET);
// Pop the stack handler and unlink this frame from the handler chain.
static_assert(StackHandlerConstants::kNextOffset == 0 * kPointerSize,
"Unexpected offset for StackHandlerConstants::kNextOffset");
__ Pop(x10, padreg);
__ Mov(x11, ExternalReference::Create(IsolateAddressId::kHandlerAddress,
isolate()));
__ Drop(StackHandlerConstants::kSlotCount - 2);
__ Str(x10, MemOperand(x11));
__ Bind(&exit);
// x0 holds the result.
// The stack pointer points to the top of the entry frame pushed on entry from
// C++ (at the beginning of this stub):
// sp[0] : padding.
// sp[1] : JS entry frame marker.
// sp[2] : C entry FP.
// sp[3] : stack frame marker.
// sp[4] : stack frame marker.
// sp[5] : bad frame pointer 0xFFF...FF <- fp points here.
// Check if the current stack frame is marked as the outermost JS frame.
Label non_outermost_js_2;
{
Register c_entry_fp = x11;
__ PeekPair(x10, c_entry_fp, 1 * kPointerSize);
__ Cmp(x10, StackFrame::OUTERMOST_JSENTRY_FRAME);
__ B(ne, &non_outermost_js_2);
__ Mov(x12, js_entry_sp);
__ Str(xzr, MemOperand(x12));
__ Bind(&non_outermost_js_2);
// Restore the top frame descriptors from the stack.
__ Mov(x12, ExternalReference::Create(IsolateAddressId::kCEntryFPAddress,
isolate()));
__ Str(c_entry_fp, MemOperand(x12));
}
// Reset the stack to the callee saved registers.
static_assert(EntryFrameConstants::kFixedFrameSize % (2 * kPointerSize) == 0,
"Size of entry frame is not a multiple of 16 bytes");
__ Drop(EntryFrameConstants::kFixedFrameSize / kPointerSize);
// Restore the callee-saved registers and return.
__ PopCalleeSavedRegisters();
__ Ret();
}
// The entry hook is a Push (stp) instruction, followed by a near call.
static const unsigned int kProfileEntryHookCallSize =
(1 * kInstrSize) + Assembler::kNearCallSize;
void ProfileEntryHookStub::MaybeCallEntryHookDelayed(TurboAssembler* tasm,
Zone* zone) {
if (tasm->isolate()->function_entry_hook() != nullptr) {
Assembler::BlockConstPoolScope no_const_pools(tasm);
DontEmitDebugCodeScope no_debug_code(tasm);
Label entry_hook_call_start;
tasm->Bind(&entry_hook_call_start);
tasm->Push(padreg, lr);
tasm->CallStubDelayed(new (zone) ProfileEntryHookStub(nullptr));
DCHECK_EQ(tasm->SizeOfCodeGeneratedSince(&entry_hook_call_start),
kProfileEntryHookCallSize);
tasm->Pop(lr, padreg);
}
}
void ProfileEntryHookStub::MaybeCallEntryHook(MacroAssembler* masm) {
if (masm->isolate()->function_entry_hook() != nullptr) {
ProfileEntryHookStub stub(masm->isolate());
Assembler::BlockConstPoolScope no_const_pools(masm);
DontEmitDebugCodeScope no_debug_code(masm);
Label entry_hook_call_start;
__ Bind(&entry_hook_call_start);
__ Push(padreg, lr);
__ CallStub(&stub);
DCHECK_EQ(masm->SizeOfCodeGeneratedSince(&entry_hook_call_start),
kProfileEntryHookCallSize);
__ Pop(lr, padreg);
}
}
void ProfileEntryHookStub::Generate(MacroAssembler* masm) {
HardAbortScope hard_aborts(masm);
// Save all kCallerSaved registers (including lr), since this can be called
// from anywhere.
// TODO(jbramley): What about FP registers?
__ PushCPURegList(kCallerSaved);
DCHECK(kCallerSaved.IncludesAliasOf(lr));
const int kNumSavedRegs = kCallerSaved.Count();
DCHECK_EQ(kNumSavedRegs % 2, 0);
// Compute the function's address as the first argument.
__ Sub(x0, lr, kProfileEntryHookCallSize);
#if V8_HOST_ARCH_ARM64
uintptr_t entry_hook =
reinterpret_cast<uintptr_t>(isolate()->function_entry_hook());
__ Mov(x10, entry_hook);
#else
// Under the simulator we need to indirect the entry hook through a trampoline
// function at a known address.
ApiFunction dispatcher(FUNCTION_ADDR(EntryHookTrampoline));
__ Mov(x10, Operand(ExternalReference::Create(
&dispatcher, ExternalReference::BUILTIN_CALL)));
// It additionally takes an isolate as a third parameter
__ Mov(x2, ExternalReference::isolate_address(isolate()));
#endif
// The caller's return address is above the saved temporaries.
// Grab its location for the second argument to the hook.
__ SlotAddress(x1, kNumSavedRegs);
{
// Create a dummy frame, as CallCFunction requires this.
FrameScope frame(masm, StackFrame::MANUAL);
__ CallCFunction(x10, 2, 0);
}
__ PopCPURegList(kCallerSaved);
__ Ret();
}
void DirectCEntryStub::Generate(MacroAssembler* masm) {
// Put return address on the stack (accessible to GC through exit frame pc).
__ Poke(lr, 0);
// Call the C++ function.
__ Blr(x10);
// Return to calling code.
__ Peek(lr, 0);
__ AssertFPCRState();
__ Ret();
}
void DirectCEntryStub::GenerateCall(MacroAssembler* masm,
Register target) {
// Branch to the stub.
__ Mov(x10, target);
__ Call(GetCode(), RelocInfo::CODE_TARGET);
}
// The number of register that CallApiFunctionAndReturn will need to save on
// the stack. The space for these registers need to be allocated in the
// ExitFrame before calling CallApiFunctionAndReturn.
static const int kCallApiFunctionSpillSpace = 4;
static int AddressOffset(ExternalReference ref0, ExternalReference ref1) {
return static_cast<int>(ref0.address() - ref1.address());
}
// Calls an API function. Allocates HandleScope, extracts returned value
// from handle and propagates exceptions.
// 'stack_space' is the space to be unwound on exit (includes the call JS
// arguments space and the additional space allocated for the fast call).
// 'spill_offset' is the offset from the stack pointer where
// CallApiFunctionAndReturn can spill registers.
static void CallApiFunctionAndReturn(MacroAssembler* masm,
Register function_address,
ExternalReference thunk_ref,
int stack_space, int spill_offset,
MemOperand return_value_operand) {
ASM_LOCATION("CallApiFunctionAndReturn");
Isolate* isolate = masm->isolate();
ExternalReference next_address =
ExternalReference::handle_scope_next_address(isolate);
const int kNextOffset = 0;
const int kLimitOffset = AddressOffset(
ExternalReference::handle_scope_limit_address(isolate), next_address);
const int kLevelOffset = AddressOffset(
ExternalReference::handle_scope_level_address(isolate), next_address);
DCHECK(function_address.is(x1) || function_address.is(x2));
Label profiler_disabled;
Label end_profiler_check;
__ Mov(x10, ExternalReference::is_profiling_address(isolate));
__ Ldrb(w10, MemOperand(x10));
__ Cbz(w10, &profiler_disabled);
__ Mov(x3, thunk_ref);
__ B(&end_profiler_check);
__ Bind(&profiler_disabled);
__ Mov(x3, function_address);
__ Bind(&end_profiler_check);
// Save the callee-save registers we are going to use.
// TODO(all): Is this necessary? ARM doesn't do it.
STATIC_ASSERT(kCallApiFunctionSpillSpace == 4);
__ Poke(x19, (spill_offset + 0) * kXRegSize);
__ Poke(x20, (spill_offset + 1) * kXRegSize);
__ Poke(x21, (spill_offset + 2) * kXRegSize);
__ Poke(x22, (spill_offset + 3) * kXRegSize);
// Allocate HandleScope in callee-save registers.
// We will need to restore the HandleScope after the call to the API function,
// by allocating it in callee-save registers they will be preserved by C code.
Register handle_scope_base = x22;
Register next_address_reg = x19;
Register limit_reg = x20;
Register level_reg = w21;
__ Mov(handle_scope_base, next_address);
__ Ldr(next_address_reg, MemOperand(handle_scope_base, kNextOffset));
__ Ldr(limit_reg, MemOperand(handle_scope_base, kLimitOffset));
__ Ldr(level_reg, MemOperand(handle_scope_base, kLevelOffset));
__ Add(level_reg, level_reg, 1);
__ Str(level_reg, MemOperand(handle_scope_base, kLevelOffset));
if (FLAG_log_timer_events) {
FrameScope frame(masm, StackFrame::MANUAL);
__ PushSafepointRegisters();
__ Mov(x0, ExternalReference::isolate_address(isolate));
__ CallCFunction(ExternalReference::log_enter_external_function(), 1);
__ PopSafepointRegisters();
}
// Native call returns to the DirectCEntry stub which redirects to the
// return address pushed on stack (could have moved after GC).
// DirectCEntry stub itself is generated early and never moves.
DirectCEntryStub stub(isolate);
stub.GenerateCall(masm, x3);
if (FLAG_log_timer_events) {
FrameScope frame(masm, StackFrame::MANUAL);
__ PushSafepointRegisters();
__ Mov(x0, ExternalReference::isolate_address(isolate));
__ CallCFunction(ExternalReference::log_leave_external_function(), 1);
__ PopSafepointRegisters();
}
Label promote_scheduled_exception;
Label delete_allocated_handles;
Label leave_exit_frame;
Label return_value_loaded;
// Load value from ReturnValue.
__ Ldr(x0, return_value_operand);
__ Bind(&return_value_loaded);
// No more valid handles (the result handle was the last one). Restore
// previous handle scope.
__ Str(next_address_reg, MemOperand(handle_scope_base, kNextOffset));
if (__ emit_debug_code()) {
__ Ldr(w1, MemOperand(handle_scope_base, kLevelOffset));
__ Cmp(w1, level_reg);
__ Check(eq, AbortReason::kUnexpectedLevelAfterReturnFromApiCall);
}
__ Sub(level_reg, level_reg, 1);
__ Str(level_reg, MemOperand(handle_scope_base, kLevelOffset));
__ Ldr(x1, MemOperand(handle_scope_base, kLimitOffset));
__ Cmp(limit_reg, x1);
__ B(ne, &delete_allocated_handles);
// Leave the API exit frame.
__ Bind(&leave_exit_frame);
// Restore callee-saved registers.
__ Peek(x19, (spill_offset + 0) * kXRegSize);
__ Peek(x20, (spill_offset + 1) * kXRegSize);
__ Peek(x21, (spill_offset + 2) * kXRegSize);
__ Peek(x22, (spill_offset + 3) * kXRegSize);
__ LeaveExitFrame(false, x1, x5);
// Check if the function scheduled an exception.
__ Mov(x5, ExternalReference::scheduled_exception_address(isolate));
__ Ldr(x5, MemOperand(x5));
__ JumpIfNotRoot(x5, Heap::kTheHoleValueRootIndex,
&promote_scheduled_exception);
__ DropSlots(stack_space);
__ Ret();
// Re-throw by promoting a scheduled exception.
__ Bind(&promote_scheduled_exception);
__ TailCallRuntime(Runtime::kPromoteScheduledException);
// HandleScope limit has changed. Delete allocated extensions.
__ Bind(&delete_allocated_handles);
__ Str(limit_reg, MemOperand(handle_scope_base, kLimitOffset));
// Save the return value in a callee-save register.
Register saved_result = x19;
__ Mov(saved_result, x0);
__ Mov(x0, ExternalReference::isolate_address(isolate));
__ CallCFunction(ExternalReference::delete_handle_scope_extensions(), 1);
__ Mov(x0, saved_result);
__ B(&leave_exit_frame);
}
void CallApiCallbackStub::Generate(MacroAssembler* masm) {
// ----------- S t a t e -------------
// -- x4 : call_data
// -- x2 : holder
// -- x1 : api_function_address
// -- cp : context
// --
// -- sp[0] : last argument
// -- ...
// -- sp[(argc - 1) * 8] : first argument
// -- sp[argc * 8] : receiver
// -----------------------------------
Register call_data = x4;
Register holder = x2;
Register api_function_address = x1;
typedef FunctionCallbackArguments FCA;
STATIC_ASSERT(FCA::kArgsLength == 6);
STATIC_ASSERT(FCA::kNewTargetIndex == 5);
STATIC_ASSERT(FCA::kDataIndex == 4);
STATIC_ASSERT(FCA::kReturnValueOffset == 3);
STATIC_ASSERT(FCA::kReturnValueDefaultValueIndex == 2);
STATIC_ASSERT(FCA::kIsolateIndex == 1);
STATIC_ASSERT(FCA::kHolderIndex == 0);
Register undef = x7;
__ LoadRoot(undef, Heap::kUndefinedValueRootIndex);
// Push new target, call data.
__ Push(undef, call_data);
Register isolate_reg = x5;
__ Mov(isolate_reg, ExternalReference::isolate_address(masm->isolate()));
// FunctionCallbackArguments:
// return value, return value default, isolate, holder.
__ Push(undef, undef, isolate_reg, holder);
// Prepare arguments.
Register args = x6;
__ Mov(args, sp);
// Allocate the v8::Arguments structure in the arguments' space, since it's
// not controlled by GC.
const int kApiStackSpace = 3;
// Allocate space so that CallApiFunctionAndReturn can store some scratch
// registers on the stack.
const int kCallApiFunctionSpillSpace = 4;
FrameScope frame_scope(masm, StackFrame::MANUAL);
__ EnterExitFrame(false, x10, kApiStackSpace + kCallApiFunctionSpillSpace);
DCHECK(!AreAliased(x0, api_function_address));
// x0 = FunctionCallbackInfo&
// Arguments is after the return address.
__ SlotAddress(x0, 1);
// FunctionCallbackInfo::implicit_args_ and FunctionCallbackInfo::values_
__ Add(x10, args, Operand((FCA::kArgsLength - 1 + argc()) * kPointerSize));
__ Stp(args, x10, MemOperand(x0, 0 * kPointerSize));
// FunctionCallbackInfo::length_ = argc
__ Mov(x10, argc());
__ Str(x10, MemOperand(x0, 2 * kPointerSize));
ExternalReference thunk_ref = ExternalReference::invoke_function_callback();
AllowExternalCallThatCantCauseGC scope(masm);
// Stores return the first js argument
int return_value_offset = 2 + FCA::kReturnValueOffset;
MemOperand return_value_operand(fp, return_value_offset * kPointerSize);
// The number of arguments might be odd, but will be padded when calling the
// stub. We do not round up stack_space to account for odd argc here, this
// will be done in CallApiFunctionAndReturn.
const int stack_space = (argc() + 1) + FCA::kArgsLength;
// The current frame needs to be aligned.
DCHECK_EQ((stack_space - (argc() + 1)) % 2, 0);
const int spill_offset = 1 + kApiStackSpace;
CallApiFunctionAndReturn(masm, api_function_address, thunk_ref, stack_space,
spill_offset, return_value_operand);
}
void CallApiGetterStub::Generate(MacroAssembler* masm) {
STATIC_ASSERT(PropertyCallbackArguments::kShouldThrowOnErrorIndex == 0);
STATIC_ASSERT(PropertyCallbackArguments::kHolderIndex == 1);
STATIC_ASSERT(PropertyCallbackArguments::kIsolateIndex == 2);
STATIC_ASSERT(PropertyCallbackArguments::kReturnValueDefaultValueIndex == 3);
STATIC_ASSERT(PropertyCallbackArguments::kReturnValueOffset == 4);
STATIC_ASSERT(PropertyCallbackArguments::kDataIndex == 5);
STATIC_ASSERT(PropertyCallbackArguments::kThisIndex == 6);
STATIC_ASSERT(PropertyCallbackArguments::kArgsLength == 7);
Register receiver = ApiGetterDescriptor::ReceiverRegister();
Register holder = ApiGetterDescriptor::HolderRegister();
Register callback = ApiGetterDescriptor::CallbackRegister();
Register data = x4;
Register undef = x5;
Register isolate_address = x6;
Register name = x7;
DCHECK(!AreAliased(receiver, holder, callback, data, undef, isolate_address,
name));
__ Ldr(data, FieldMemOperand(callback, AccessorInfo::kDataOffset));
__ LoadRoot(undef, Heap::kUndefinedValueRootIndex);
__ Mov(isolate_address, ExternalReference::isolate_address(isolate()));
__ Ldr(name, FieldMemOperand(callback, AccessorInfo::kNameOffset));
// PropertyCallbackArguments:
// receiver, data, return value, return value default, isolate, holder,
// should_throw_on_error
// These are followed by the property name, which is also pushed below the
// exit frame to make the GC aware of it.
__ Push(receiver, data, undef, undef, isolate_address, holder, xzr, name);
// v8::PropertyCallbackInfo::args_ array and name handle.
static const int kStackUnwindSpace =
PropertyCallbackArguments::kArgsLength + 1;
static_assert(kStackUnwindSpace % 2 == 0,
"slots must be a multiple of 2 for stack pointer alignment");
// Load address of v8::PropertyAccessorInfo::args_ array and name handle.
__ Mov(x0, sp); // x0 = Handle<Name>
__ Add(x1, x0, 1 * kPointerSize); // x1 = v8::PCI::args_
const int kApiStackSpace = 1;
// Allocate space so that CallApiFunctionAndReturn can store some scratch
// registers on the stack.
const int kCallApiFunctionSpillSpace = 4;
FrameScope frame_scope(masm, StackFrame::MANUAL);
__ EnterExitFrame(false, x10, kApiStackSpace + kCallApiFunctionSpillSpace);
// Create v8::PropertyCallbackInfo object on the stack and initialize
// it's args_ field.
__ Poke(x1, 1 * kPointerSize);
__ SlotAddress(x1, 1);
// x1 = v8::PropertyCallbackInfo&
ExternalReference thunk_ref =
ExternalReference::invoke_accessor_getter_callback();
Register api_function_address = x2;
Register js_getter = x4;
__ Ldr(js_getter, FieldMemOperand(callback, AccessorInfo::kJsGetterOffset));
__ Ldr(api_function_address,
FieldMemOperand(js_getter, Foreign::kForeignAddressOffset));
const int spill_offset = 1 + kApiStackSpace;
// +3 is to skip prolog, return address and name handle.
MemOperand return_value_operand(
fp, (PropertyCallbackArguments::kReturnValueOffset + 3) * kPointerSize);
CallApiFunctionAndReturn(masm, api_function_address, thunk_ref,
kStackUnwindSpace, spill_offset,
return_value_operand);
}
#undef __
} // namespace internal
} // namespace v8
#endif // V8_TARGET_ARCH_ARM64