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// Copyright 2014 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.
#include "src/compiler/linkage.h"
#include "src/assembler-inl.h"
#include "src/code-stubs.h"
#include "src/compiler/common-operator.h"
#include "src/compiler/frame.h"
#include "src/compiler/node.h"
#include "src/compiler/osr.h"
#include "src/compiler/pipeline.h"
#include "src/optimized-compilation-info.h"
namespace v8 {
namespace internal {
namespace compiler {
namespace {
inline LinkageLocation regloc(Register reg, MachineType type) {
return LinkageLocation::ForRegister(reg.code(), type);
}
} // namespace
std::ostream& operator<<(std::ostream& os, const CallDescriptor::Kind& k) {
switch (k) {
case CallDescriptor::kCallCodeObject:
os << "Code";
break;
case CallDescriptor::kCallJSFunction:
os << "JS";
break;
case CallDescriptor::kCallAddress:
os << "Addr";
break;
case CallDescriptor::kCallWasmFunction:
os << "Wasm";
break;
}
return os;
}
std::ostream& operator<<(std::ostream& os, const CallDescriptor& d) {
// TODO(svenpanne) Output properties etc. and be less cryptic.
return os << d.kind() << ":" << d.debug_name() << ":r" << d.ReturnCount()
<< "s" << d.StackParameterCount() << "i" << d.InputCount() << "f"
<< d.FrameStateCount();
}
MachineSignature* CallDescriptor::GetMachineSignature(Zone* zone) const {
size_t param_count = ParameterCount();
size_t return_count = ReturnCount();
MachineType* types = zone->NewArray<MachineType>(param_count + return_count);
int current = 0;
for (size_t i = 0; i < return_count; ++i) {
types[current++] = GetReturnType(i);
}
for (size_t i = 0; i < param_count; ++i) {
types[current++] = GetParameterType(i);
}
return new (zone) MachineSignature(return_count, param_count, types);
}
bool CallDescriptor::HasSameReturnLocationsAs(
const CallDescriptor* other) const {
if (ReturnCount() != other->ReturnCount()) return false;
for (size_t i = 0; i < ReturnCount(); ++i) {
if (GetReturnLocation(i) != other->GetReturnLocation(i)) return false;
}
return true;
}
int CallDescriptor::GetFirstUnusedStackSlot() const {
int slots_above_sp = 0;
for (size_t i = 0; i < InputCount(); ++i) {
LinkageLocation operand = GetInputLocation(i);
if (!operand.IsRegister()) {
int new_candidate =
-operand.GetLocation() + operand.GetSizeInPointers() - 1;
if (new_candidate > slots_above_sp) {
slots_above_sp = new_candidate;
}
}
}
return slots_above_sp;
}
int CallDescriptor::GetStackParameterDelta(
CallDescriptor const* tail_caller) const {
int callee_slots_above_sp = GetFirstUnusedStackSlot();
int tail_caller_slots_above_sp = tail_caller->GetFirstUnusedStackSlot();
int stack_param_delta = callee_slots_above_sp - tail_caller_slots_above_sp;
if (kPadArguments) {
// Adjust stack delta when it is odd.
if (stack_param_delta % 2 != 0) {
if (callee_slots_above_sp % 2 != 0) {
// The delta is odd due to the callee - we will need to add one slot
// of padding.
++stack_param_delta;
} else {
// The delta is odd because of the caller. We already have one slot of
// padding that we can reuse for arguments, so we will need one fewer
// slot.
--stack_param_delta;
}
}
}
return stack_param_delta;
}
bool CallDescriptor::CanTailCall(const Node* node) const {
return HasSameReturnLocationsAs(CallDescriptorOf(node->op()));
}
int CallDescriptor::CalculateFixedFrameSize() const {
switch (kind_) {
case kCallJSFunction:
return PushArgumentCount()
? OptimizedBuiltinFrameConstants::kFixedSlotCount
: StandardFrameConstants::kFixedSlotCount;
case kCallAddress:
return CommonFrameConstants::kFixedSlotCountAboveFp +
CommonFrameConstants::kCPSlotCount;
case kCallCodeObject:
return TypedFrameConstants::kFixedSlotCount;
case kCallWasmFunction:
return WasmCompiledFrameConstants::kFixedSlotCount;
}
UNREACHABLE();
}
CallDescriptor* Linkage::ComputeIncoming(Zone* zone,
OptimizedCompilationInfo* info) {
DCHECK(!info->IsStub());
if (!info->closure().is_null()) {
// If we are compiling a JS function, use a JS call descriptor,
// plus the receiver.
SharedFunctionInfo* shared = info->closure()->shared();
return GetJSCallDescriptor(zone, info->is_osr(),
1 + shared->internal_formal_parameter_count(),
CallDescriptor::kNoFlags);
}
return nullptr; // TODO(titzer): ?
}
// static
bool Linkage::NeedsFrameStateInput(Runtime::FunctionId function) {
switch (function) {
// Most runtime functions need a FrameState. A few chosen ones that we know
// not to call into arbitrary JavaScript, not to throw, and not to lazily
// deoptimize are whitelisted here and can be called without a FrameState.
case Runtime::kAbort:
case Runtime::kAllocateInTargetSpace:
case Runtime::kCreateIterResultObject:
case Runtime::kIncBlockCounter:
case Runtime::kIsFunction:
case Runtime::kNewClosure:
case Runtime::kNewClosure_Tenured:
case Runtime::kNewFunctionContext:
case Runtime::kPushBlockContext:
case Runtime::kPushCatchContext:
case Runtime::kReThrow:
case Runtime::kStringEqual:
case Runtime::kStringNotEqual:
case Runtime::kStringLessThan:
case Runtime::kStringLessThanOrEqual:
case Runtime::kStringGreaterThan:
case Runtime::kStringGreaterThanOrEqual:
case Runtime::kToFastProperties: // TODO(conradw): Is it safe?
case Runtime::kTraceEnter:
case Runtime::kTraceExit:
return false;
// Some inline intrinsics are also safe to call without a FrameState.
case Runtime::kInlineCreateIterResultObject:
case Runtime::kInlineGeneratorClose:
case Runtime::kInlineGeneratorGetInputOrDebugPos:
case Runtime::kInlineGeneratorGetResumeMode:
case Runtime::kInlineCreateJSGeneratorObject:
case Runtime::kInlineIsArray:
case Runtime::kInlineIsJSWeakMap:
case Runtime::kInlineIsJSWeakSet:
case Runtime::kInlineIsJSReceiver:
case Runtime::kInlineIsRegExp:
case Runtime::kInlineIsSmi:
case Runtime::kInlineIsTypedArray:
return false;
default:
break;
}
// For safety, default to needing a FrameState unless whitelisted.
return true;
}
bool CallDescriptor::UsesOnlyRegisters() const {
for (size_t i = 0; i < InputCount(); ++i) {
if (!GetInputLocation(i).IsRegister()) return false;
}
for (size_t i = 0; i < ReturnCount(); ++i) {
if (!GetReturnLocation(i).IsRegister()) return false;
}
return true;
}
CallDescriptor* Linkage::GetRuntimeCallDescriptor(
Zone* zone, Runtime::FunctionId function_id, int js_parameter_count,
Operator::Properties properties, CallDescriptor::Flags flags) {
const Runtime::Function* function = Runtime::FunctionForId(function_id);
const int return_count = function->result_size;
const char* debug_name = function->name;
if (!Linkage::NeedsFrameStateInput(function_id)) {
flags = static_cast<CallDescriptor::Flags>(
flags & ~CallDescriptor::kNeedsFrameState);
}
return GetCEntryStubCallDescriptor(zone, return_count, js_parameter_count,
debug_name, properties, flags);
}
CallDescriptor* Linkage::GetCEntryStubCallDescriptor(
Zone* zone, int return_count, int js_parameter_count,
const char* debug_name, Operator::Properties properties,
CallDescriptor::Flags flags) {
const size_t function_count = 1;
const size_t num_args_count = 1;
const size_t context_count = 1;
const size_t parameter_count = function_count +
static_cast<size_t>(js_parameter_count) +
num_args_count + context_count;
LocationSignature::Builder locations(zone, static_cast<size_t>(return_count),
static_cast<size_t>(parameter_count));
// Add returns.
if (locations.return_count_ > 0) {
locations.AddReturn(regloc(kReturnRegister0, MachineType::AnyTagged()));
}
if (locations.return_count_ > 1) {
locations.AddReturn(regloc(kReturnRegister1, MachineType::AnyTagged()));
}
if (locations.return_count_ > 2) {
locations.AddReturn(regloc(kReturnRegister2, MachineType::AnyTagged()));
}
// All parameters to the runtime call go on the stack.
for (int i = 0; i < js_parameter_count; i++) {
locations.AddParam(LinkageLocation::ForCallerFrameSlot(
i - js_parameter_count, MachineType::AnyTagged()));
}
// Add runtime function itself.
locations.AddParam(
regloc(kRuntimeCallFunctionRegister, MachineType::Pointer()));
// Add runtime call argument count.
locations.AddParam(
regloc(kRuntimeCallArgCountRegister, MachineType::Int32()));
// Add context.
locations.AddParam(regloc(kContextRegister, MachineType::AnyTagged()));
// The target for runtime calls is a code object.
MachineType target_type = MachineType::AnyTagged();
LinkageLocation target_loc =
LinkageLocation::ForAnyRegister(MachineType::AnyTagged());
return new (zone) CallDescriptor( // --
CallDescriptor::kCallCodeObject, // kind
target_type, // target MachineType
target_loc, // target location
locations.Build(), // location_sig
js_parameter_count, // stack_parameter_count
properties, // properties
kNoCalleeSaved, // callee-saved
kNoCalleeSaved, // callee-saved fp
flags, // flags
debug_name); // debug name
}
CallDescriptor* Linkage::GetJSCallDescriptor(Zone* zone, bool is_osr,
int js_parameter_count,
CallDescriptor::Flags flags) {
const size_t return_count = 1;
const size_t context_count = 1;
const size_t new_target_count = 1;
const size_t num_args_count = 1;
const size_t parameter_count =
js_parameter_count + new_target_count + num_args_count + context_count;
LocationSignature::Builder locations(zone, return_count, parameter_count);
// All JS calls have exactly one return value.
locations.AddReturn(regloc(kReturnRegister0, MachineType::AnyTagged()));
// All parameters to JS calls go on the stack.
for (int i = 0; i < js_parameter_count; i++) {
int spill_slot_index = i - js_parameter_count;
locations.AddParam(LinkageLocation::ForCallerFrameSlot(
spill_slot_index, MachineType::AnyTagged()));
}
// Add JavaScript call new target value.
locations.AddParam(
regloc(kJavaScriptCallNewTargetRegister, MachineType::AnyTagged()));
// Add JavaScript call argument count.
locations.AddParam(
regloc(kJavaScriptCallArgCountRegister, MachineType::Int32()));
// Add context.
locations.AddParam(regloc(kContextRegister, MachineType::AnyTagged()));
// The target for JS function calls is the JSFunction object.
MachineType target_type = MachineType::AnyTagged();
// When entering into an OSR function from unoptimized code the JSFunction
// is not in a register, but it is on the stack in the marker spill slot.
LinkageLocation target_loc =
is_osr ? LinkageLocation::ForSavedCallerFunction()
: regloc(kJSFunctionRegister, MachineType::AnyTagged());
return new (zone) CallDescriptor( // --
CallDescriptor::kCallJSFunction, // kind
target_type, // target MachineType
target_loc, // target location
locations.Build(), // location_sig
js_parameter_count, // stack_parameter_count
Operator::kNoProperties, // properties
kNoCalleeSaved, // callee-saved
kNoCalleeSaved, // callee-saved fp
CallDescriptor::kCanUseRoots | // flags
flags, // flags
"js-call");
}
// TODO(turbofan): cache call descriptors for code stub calls.
CallDescriptor* Linkage::GetStubCallDescriptor(
Zone* zone, const CallInterfaceDescriptor& descriptor,
int stack_parameter_count, CallDescriptor::Flags flags,
Operator::Properties properties, StubCallMode stub_mode) {
const int register_parameter_count = descriptor.GetRegisterParameterCount();
const int js_parameter_count =
register_parameter_count + stack_parameter_count;
const int context_count = descriptor.HasContextParameter() ? 1 : 0;
const size_t parameter_count =
static_cast<size_t>(js_parameter_count + context_count);
size_t return_count = descriptor.GetReturnCount();
LocationSignature::Builder locations(zone, return_count, parameter_count);
// Add returns.
if (locations.return_count_ > 0) {
locations.AddReturn(regloc(kReturnRegister0, descriptor.GetReturnType(0)));
}
if (locations.return_count_ > 1) {
locations.AddReturn(regloc(kReturnRegister1, descriptor.GetReturnType(1)));
}
if (locations.return_count_ > 2) {
locations.AddReturn(regloc(kReturnRegister2, descriptor.GetReturnType(2)));
}
// Add parameters in registers and on the stack.
for (int i = 0; i < js_parameter_count; i++) {
if (i < register_parameter_count) {
// The first parameters go in registers.
Register reg = descriptor.GetRegisterParameter(i);
MachineType type = descriptor.GetParameterType(i);
locations.AddParam(regloc(reg, type));
} else {
// The rest of the parameters go on the stack.
int stack_slot = i - register_parameter_count - stack_parameter_count;
locations.AddParam(LinkageLocation::ForCallerFrameSlot(
stack_slot, MachineType::AnyTagged()));
}
}
// Add context.
if (context_count) {
locations.AddParam(regloc(kContextRegister, MachineType::AnyTagged()));
}
// The target for stub calls depends on the requested mode.
CallDescriptor::Kind kind = stub_mode == StubCallMode::kCallWasmRuntimeStub
? CallDescriptor::kCallWasmFunction
: CallDescriptor::kCallCodeObject;
MachineType target_type = stub_mode == StubCallMode::kCallWasmRuntimeStub
? MachineType::Pointer()
: MachineType::AnyTagged();
LinkageLocation target_loc = LinkageLocation::ForAnyRegister(target_type);
return new (zone) CallDescriptor( // --
kind, // kind
target_type, // target MachineType
target_loc, // target location
locations.Build(), // location_sig
stack_parameter_count, // stack_parameter_count
properties, // properties
kNoCalleeSaved, // callee-saved registers
kNoCalleeSaved, // callee-saved fp
CallDescriptor::kCanUseRoots | flags, // flags
descriptor.DebugName(), // debug name
descriptor.allocatable_registers());
}
// static
CallDescriptor* Linkage::GetBytecodeDispatchCallDescriptor(
Zone* zone, const CallInterfaceDescriptor& descriptor,
int stack_parameter_count) {
const int register_parameter_count = descriptor.GetRegisterParameterCount();
const int parameter_count = register_parameter_count + stack_parameter_count;
DCHECK_EQ(descriptor.GetReturnCount(), 1);
LocationSignature::Builder locations(zone, 1, parameter_count);
locations.AddReturn(regloc(kReturnRegister0, descriptor.GetReturnType(0)));
// Add parameters in registers and on the stack.
for (int i = 0; i < parameter_count; i++) {
if (i < register_parameter_count) {
// The first parameters go in registers.
Register reg = descriptor.GetRegisterParameter(i);
MachineType type = descriptor.GetParameterType(i);
locations.AddParam(regloc(reg, type));
} else {
// The rest of the parameters go on the stack.
int stack_slot = i - register_parameter_count - stack_parameter_count;
locations.AddParam(LinkageLocation::ForCallerFrameSlot(
stack_slot, MachineType::AnyTagged()));
}
}
// The target for interpreter dispatches is a code entry address.
MachineType target_type = MachineType::Pointer();
LinkageLocation target_loc = LinkageLocation::ForAnyRegister(target_type);
const CallDescriptor::Flags kFlags =
CallDescriptor::kCanUseRoots | CallDescriptor::kFixedTargetRegister;
return new (zone) CallDescriptor( // --
CallDescriptor::kCallAddress, // kind
target_type, // target MachineType
target_loc, // target location
locations.Build(), // location_sig
stack_parameter_count, // stack_parameter_count
Operator::kNoProperties, // properties
kNoCalleeSaved, // callee-saved registers
kNoCalleeSaved, // callee-saved fp
kFlags, // flags
descriptor.DebugName());
}
LinkageLocation Linkage::GetOsrValueLocation(int index) const {
CHECK(incoming_->IsJSFunctionCall());
int parameter_count = static_cast<int>(incoming_->JSParameterCount() - 1);
int first_stack_slot = OsrHelper::FirstStackSlotIndex(parameter_count);
if (index == kOsrContextSpillSlotIndex) {
// Context. Use the parameter location of the context spill slot.
// Parameter (arity + 2) is special for the context of the function frame.
// >> context_index = target + receiver + params + new_target + #args
int context_index = 1 + 1 + parameter_count + 1 + 1;
return incoming_->GetInputLocation(context_index);
} else if (index >= first_stack_slot) {
// Local variable stored in this (callee) stack.
int spill_index =
index - first_stack_slot + StandardFrameConstants::kFixedSlotCount;
return LinkageLocation::ForCalleeFrameSlot(spill_index,
MachineType::AnyTagged());
} else {
// Parameter. Use the assigned location from the incoming call descriptor.
int parameter_index = 1 + index; // skip index 0, which is the target.
return incoming_->GetInputLocation(parameter_index);
}
}
namespace {
inline bool IsTaggedReg(const LinkageLocation& loc, Register reg) {
return loc.IsRegister() && loc.AsRegister() == reg.code() &&
loc.GetType().representation() ==
MachineRepresentation::kTaggedPointer;
}
} // namespace
bool Linkage::ParameterHasSecondaryLocation(int index) const {
// TODO(titzer): this should be configurable, not call-type specific.
if (incoming_->IsJSFunctionCall()) {
LinkageLocation loc = GetParameterLocation(index);
return IsTaggedReg(loc, kJSFunctionRegister) ||
IsTaggedReg(loc, kContextRegister);
}
if (incoming_->IsWasmFunctionCall()) {
LinkageLocation loc = GetParameterLocation(index);
return IsTaggedReg(loc, kWasmInstanceRegister);
}
return false;
}
LinkageLocation Linkage::GetParameterSecondaryLocation(int index) const {
// TODO(titzer): these constants are necessary due to offset/slot# mismatch
static const int kJSContextSlot = 2 + StandardFrameConstants::kCPSlotCount;
static const int kJSFunctionSlot = 3 + StandardFrameConstants::kCPSlotCount;
static const int kWasmInstanceSlot = 3 + StandardFrameConstants::kCPSlotCount;
DCHECK(ParameterHasSecondaryLocation(index));
LinkageLocation loc = GetParameterLocation(index);
// TODO(titzer): this should be configurable, not call-type specific.
if (incoming_->IsJSFunctionCall()) {
if (IsTaggedReg(loc, kJSFunctionRegister)) {
return LinkageLocation::ForCalleeFrameSlot(kJSFunctionSlot,
MachineType::AnyTagged());
} else {
DCHECK(IsTaggedReg(loc, kContextRegister));
return LinkageLocation::ForCalleeFrameSlot(kJSContextSlot,
MachineType::AnyTagged());
}
}
if (incoming_->IsWasmFunctionCall()) {
DCHECK(IsTaggedReg(loc, kWasmInstanceRegister));
return LinkageLocation::ForCalleeFrameSlot(kWasmInstanceSlot,
MachineType::AnyTagged());
}
UNREACHABLE();
return LinkageLocation::ForCalleeFrameSlot(0, MachineType::AnyTagged());
}
} // namespace compiler
} // namespace internal
} // namespace v8
|