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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef jit_WarpBuilderShared_h
#define jit_WarpBuilderShared_h
#include "mozilla/Attributes.h"
#include "mozilla/Maybe.h"
#include "jit/MIRGraph.h"
#include "js/Value.h"
namespace js {
class BytecodeLocation;
namespace jit {
class MBasicBlock;
class MCall;
class MConstant;
class MInstruction;
class MIRGenerator;
class TempAllocator;
class WarpSnapshot;
class WrappedFunction;
// Helper class to manage call state.
class MOZ_STACK_CLASS CallInfo {
MDefinition* callee_ = nullptr;
MDefinition* thisArg_ = nullptr;
MDefinition* newTargetArg_ = nullptr;
MDefinitionVector args_;
bool constructing_;
// True if the caller does not use the return value.
bool ignoresReturnValue_;
bool inlined_ = false;
bool setter_ = false;
public:
// For normal calls and FunCall we can shuffle around definitions in
// the CallInfo and use a normal MCall. For others, we need to use a
// specialized call.
enum class ArgFormat {
Standard,
Array,
FunApplyArgsObj,
};
private:
ArgFormat argFormat_ = ArgFormat::Standard;
mozilla::Maybe<ResumeMode> inliningMode_;
public:
CallInfo(TempAllocator& alloc, bool constructing, bool ignoresReturnValue,
jsbytecode* pc = nullptr)
: args_(alloc),
constructing_(constructing),
ignoresReturnValue_(ignoresReturnValue) {}
[[nodiscard]] bool init(MBasicBlock* current, uint32_t argc) {
MOZ_ASSERT(args_.empty());
// Get the arguments in the right order
if (!args_.reserve(argc)) {
return false;
}
if (constructing()) {
setNewTarget(current->pop());
}
for (int32_t i = argc; i > 0; i--) {
args_.infallibleAppend(current->peek(-i));
}
current->popn(argc);
// Get |this| and |callee|
setThis(current->pop());
setCallee(current->pop());
return true;
}
void initForSpreadCall(MBasicBlock* current) {
MOZ_ASSERT(args_.empty());
if (constructing()) {
setNewTarget(current->pop());
}
// Spread calls have one argument, an Array object containing the args.
static_assert(decltype(args_)::InlineLength >= 1,
"Appending one argument should be infallible");
MOZ_ALWAYS_TRUE(args_.append(current->pop()));
// Get |this| and |callee|
setThis(current->pop());
setCallee(current->pop());
argFormat_ = ArgFormat::Array;
}
void initForGetterCall(MDefinition* callee, MDefinition* thisVal) {
MOZ_ASSERT(args_.empty());
setCallee(callee);
setThis(thisVal);
}
void initForProxyGet(MDefinition* callee, MDefinition* handler,
MDefinition* target, MDefinition* id,
MDefinition* receiver) {
MOZ_ASSERT(args_.empty());
setCallee(callee);
setThis(handler);
static_assert(decltype(args_)::InlineLength >= 3,
"Appending three arguments should be infallible");
MOZ_ALWAYS_TRUE(args_.append(target));
MOZ_ALWAYS_TRUE(args_.append(id));
MOZ_ALWAYS_TRUE(args_.append(receiver));
}
void initForSetterCall(MDefinition* callee, MDefinition* thisVal,
MDefinition* rhs) {
MOZ_ASSERT(args_.empty());
markAsSetter();
setCallee(callee);
setThis(thisVal);
static_assert(decltype(args_)::InlineLength >= 1,
"Appending one argument should be infallible");
MOZ_ALWAYS_TRUE(args_.append(rhs));
}
void initForApplyInlinedArgs(MDefinition* callee, MDefinition* thisVal,
uint32_t numActuals) {
MOZ_ASSERT(args_.empty());
MOZ_ASSERT(!constructing_);
setCallee(callee);
setThis(thisVal);
MOZ_ASSERT(numActuals <= ArgumentsObject::MaxInlinedArgs);
static_assert(
ArgumentsObject::MaxInlinedArgs <= decltype(args_)::InlineLength,
"Actual arguments can be infallibly stored inline");
MOZ_ALWAYS_TRUE(args_.reserve(numActuals));
}
[[nodiscard]] bool initForApplyArray(MDefinition* callee,
MDefinition* thisVal,
uint32_t numActuals) {
MOZ_ASSERT(args_.empty());
MOZ_ASSERT(!constructing_);
setCallee(callee);
setThis(thisVal);
return args_.reserve(numActuals);
}
[[nodiscard]] bool initForConstructArray(MDefinition* callee,
MDefinition* thisVal,
MDefinition* newTarget,
uint32_t numActuals) {
MOZ_ASSERT(args_.empty());
MOZ_ASSERT(constructing_);
setCallee(callee);
setThis(thisVal);
setNewTarget(newTarget);
return args_.reserve(numActuals);
}
void initForCloseIter(MDefinition* iter, MDefinition* callee) {
MOZ_ASSERT(args_.empty());
setCallee(callee);
setThis(iter);
}
void popCallStack(MBasicBlock* current) { current->popn(numFormals()); }
[[nodiscard]] bool pushCallStack(MBasicBlock* current) {
current->push(callee());
current->push(thisArg());
for (uint32_t i = 0; i < argc(); i++) {
current->push(getArg(i));
}
if (constructing()) {
current->push(getNewTarget());
}
return true;
}
uint32_t argc() const { return args_.length(); }
uint32_t numFormals() const { return argc() + 2 + constructing(); }
[[nodiscard]] bool setArgs(const MDefinitionVector& args) {
MOZ_ASSERT(args_.empty());
return args_.appendAll(args);
}
MDefinitionVector& argv() { return args_; }
const MDefinitionVector& argv() const { return args_; }
MDefinition* getArg(uint32_t i) const {
MOZ_ASSERT(i < argc());
return args_[i];
}
void initArg(uint32_t i, MDefinition* def) {
MOZ_ASSERT(i == argc());
args_.infallibleAppend(def);
}
void setArg(uint32_t i, MDefinition* def) {
MOZ_ASSERT(i < argc());
args_[i] = def;
}
void removeArg(uint32_t i) { args_.erase(&args_[i]); }
MDefinition* thisArg() const {
MOZ_ASSERT(thisArg_);
return thisArg_;
}
void setThis(MDefinition* thisArg) { thisArg_ = thisArg; }
bool constructing() const { return constructing_; }
bool ignoresReturnValue() const { return ignoresReturnValue_; }
void setNewTarget(MDefinition* newTarget) {
MOZ_ASSERT(constructing());
newTargetArg_ = newTarget;
}
MDefinition* getNewTarget() const {
MOZ_ASSERT(newTargetArg_);
return newTargetArg_;
}
bool isSetter() const { return setter_; }
void markAsSetter() { setter_ = true; }
bool isInlined() const { return inlined_; }
void markAsInlined() { inlined_ = true; }
ResumeMode inliningResumeMode() const {
MOZ_ASSERT(isInlined());
return *inliningMode_;
}
void setInliningResumeMode(ResumeMode mode) {
MOZ_ASSERT(isInlined());
MOZ_ASSERT(inliningMode_.isNothing());
inliningMode_.emplace(mode);
}
MDefinition* callee() const {
MOZ_ASSERT(callee_);
return callee_;
}
void setCallee(MDefinition* callee) { callee_ = callee; }
template <typename Fun>
void forEachCallOperand(Fun& f) {
f(callee_);
f(thisArg_);
if (newTargetArg_) {
f(newTargetArg_);
}
for (uint32_t i = 0; i < argc(); i++) {
f(getArg(i));
}
}
// Prepend `numArgs` arguments. Calls `f(i)` for each new argument.
template <typename Fun>
[[nodiscard]] bool prependArgs(size_t numArgs, const Fun& f) {
size_t numArgsBefore = args_.length();
if (!args_.growBy(numArgs)) {
return false;
}
for (size_t i = numArgsBefore; i > 0; i--) {
args_[numArgs + i - 1] = args_[i - 1];
}
for (size_t i = 0; i < numArgs; i++) {
args_[i] = f(i);
}
return true;
}
void setImplicitlyUsedUnchecked() {
auto setFlag = [](MDefinition* def) { def->setImplicitlyUsedUnchecked(); };
forEachCallOperand(setFlag);
}
ArgFormat argFormat() const { return argFormat_; }
void setArgFormat(ArgFormat argFormat) { argFormat_ = argFormat; }
MDefinition* arrayArg() const {
MOZ_ASSERT(argFormat_ == ArgFormat::Array);
// The array argument for a spread call or FunApply is always the last
// argument.
return getArg(argc() - 1);
}
};
template <typename Undef>
MCall* MakeCall(TempAllocator& alloc, Undef addUndefined, CallInfo& callInfo,
bool needsThisCheck, WrappedFunction* target, bool isDOMCall) {
MOZ_ASSERT(callInfo.argFormat() == CallInfo::ArgFormat::Standard);
MOZ_ASSERT_IF(needsThisCheck, !target);
MOZ_ASSERT_IF(isDOMCall, target->jitInfo()->type() == JSJitInfo::Method);
mozilla::Maybe<DOMObjectKind> objKind;
if (isDOMCall) {
const Shape* shape = callInfo.thisArg()->toGuardShape()->shape();
MOZ_ASSERT(shape->getObjectClass()->isDOMClass());
if (shape->isNative()) {
objKind.emplace(DOMObjectKind::Native);
} else {
MOZ_ASSERT(shape->isProxy());
objKind.emplace(DOMObjectKind::Proxy);
}
}
uint32_t targetArgs = callInfo.argc();
// Collect number of missing arguments provided that the target is
// scripted. Native functions are passed an explicit 'argc' parameter.
if (target && target->hasJitEntry()) {
targetArgs = std::max<uint32_t>(target->nargs(), callInfo.argc());
}
MCall* call =
MCall::New(alloc, target, targetArgs + 1 + callInfo.constructing(),
callInfo.argc(), callInfo.constructing(),
callInfo.ignoresReturnValue(), isDOMCall, objKind);
if (!call) {
return nullptr;
}
if (callInfo.constructing()) {
// Note: setThis should have been done by the caller of makeCall.
if (needsThisCheck) {
call->setNeedsThisCheck();
}
// Pass |new.target|
call->addArg(targetArgs + 1, callInfo.getNewTarget());
}
// Explicitly pad any missing arguments with |undefined|.
// This permits skipping the argumentsRectifier.
MOZ_ASSERT_IF(target && targetArgs > callInfo.argc(), target->hasJitEntry());
MConstant* undef = nullptr;
for (uint32_t i = targetArgs; i > callInfo.argc(); i--) {
if (!undef) {
undef = addUndefined();
}
if (!alloc.ensureBallast()) {
return nullptr;
}
call->addArg(i, undef);
}
// Add explicit arguments.
// Skip addArg(0) because it is reserved for |this|.
for (int32_t i = callInfo.argc() - 1; i >= 0; i--) {
call->addArg(i + 1, callInfo.getArg(i));
}
if (isDOMCall) {
// Now that we've told it about all the args, compute whether it's movable
call->computeMovable();
}
// Pass |this| and callee.
call->addArg(0, callInfo.thisArg());
call->initCallee(callInfo.callee());
if (target) {
// The callee must be a JSFunction so we don't need a Class check.
call->disableClassCheck();
}
return call;
}
// Base class for code sharing between WarpBuilder and WarpCacheIRTranspiler.
// Because this code is used by WarpCacheIRTranspiler we should
// generally assume that we only have access to the current basic block.
class WarpBuilderShared {
WarpSnapshot& snapshot_;
MIRGenerator& mirGen_;
TempAllocator& alloc_;
protected:
MBasicBlock* current;
WarpBuilderShared(WarpSnapshot& snapshot, MIRGenerator& mirGen,
MBasicBlock* current_);
[[nodiscard]] bool resumeAfter(MInstruction* ins, BytecodeLocation loc);
MConstant* constant(const JS::Value& v);
void pushConstant(const JS::Value& v);
// Note: unboxObjectInfallible defaults to adding a non-movable MUnbox to
// ensure we don't hoist the infallible unbox before a branch checking the
// value type.
enum class IsMovable : bool { No, Yes };
MDefinition* unboxObjectInfallible(MDefinition* def,
IsMovable movable = IsMovable::No);
MCall* makeCall(CallInfo& callInfo, bool needsThisCheck,
WrappedFunction* target = nullptr, bool isDOMCall = false);
MInstruction* makeSpreadCall(CallInfo& callInfo, bool needsThisCheck,
bool isSameRealm = false,
WrappedFunction* target = nullptr);
public:
MBasicBlock* currentBlock() const { return current; }
WarpSnapshot& snapshot() const { return snapshot_; }
MIRGenerator& mirGen() { return mirGen_; }
TempAllocator& alloc() { return alloc_; }
};
} // namespace jit
} // namespace js
#endif