darling-JavaScriptCore/bytecode/Operands.h

403 lines
13 KiB
C++

/*
* Copyright (C) 2011-2019 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include "CallFrame.h"
#include "VirtualRegister.h"
#include <wtf/PrintStream.h>
#include <wtf/Vector.h>
namespace JSC {
template<typename T> struct OperandValueTraits;
constexpr unsigned maxNumCheckpointTmps = 4;
// A OperandKind::Tmp is one that exists for exiting to a checkpoint but does not exist between bytecodes.
enum class OperandKind : uint32_t { Argument, Local, Tmp }; // Keep bit-width in sync with Operand::operandKindBits' definition.
static constexpr OperandKind lastOperandKind = OperandKind::Tmp;
class Operand {
public:
static constexpr unsigned kindBits = WTF::getMSBSetConstexpr(static_cast<std::underlying_type_t<OperandKind>>(lastOperandKind)) + 1;
static constexpr unsigned maxBits = 32 + kindBits;
static_assert(maxBits == 34);
Operand() = default;
Operand(const Operand&) = default;
Operand(VirtualRegister operand)
: Operand(operand.isLocal() ? OperandKind::Local : OperandKind::Argument, operand.offset())
{ }
Operand(OperandKind kind, int operand)
#if CPU(LITTLE_ENDIAN)
: m_operand(operand)
, m_kind(kind)
#else
: m_kind(kind)
, m_operand(operand)
#endif
{
ASSERT(kind == OperandKind::Tmp || VirtualRegister(operand).isLocal() == (kind == OperandKind::Local));
}
static Operand tmp(uint32_t index) { return Operand(OperandKind::Tmp, index); }
OperandKind kind() const { return m_kind; }
int value() const { return m_operand; }
VirtualRegister virtualRegister() const
{
ASSERT(m_kind != OperandKind::Tmp);
return VirtualRegister(m_operand);
}
uint64_t asBits() const
{
uint64_t bits = bitwise_cast<uint64_t>(*this);
ASSERT(bits < (1ULL << maxBits));
return bits;
}
static Operand fromBits(uint64_t value);
bool isTmp() const { return kind() == OperandKind::Tmp; }
bool isArgument() const { return kind() == OperandKind::Argument; }
bool isLocal() const { return kind() == OperandKind::Local && virtualRegister().isLocal(); }
bool isHeader() const { return kind() != OperandKind::Tmp && virtualRegister().isHeader(); }
bool isConstant() const { return kind() != OperandKind::Tmp && virtualRegister().isConstant(); }
int toArgument() const { ASSERT(isArgument()); return virtualRegister().toArgument(); }
int toLocal() const { ASSERT(isLocal()); return virtualRegister().toLocal(); }
inline bool isValid() const;
inline bool operator==(const Operand&) const;
void dump(PrintStream&) const;
private:
#if CPU(LITTLE_ENDIAN)
int m_operand { VirtualRegister::invalidVirtualRegister };
OperandKind m_kind { OperandKind::Argument };
#else
OperandKind m_kind { OperandKind::Argument };
int m_operand { VirtualRegister::invalidVirtualRegister };
#endif
};
ALWAYS_INLINE bool Operand::operator==(const Operand& other) const
{
if (kind() != other.kind())
return false;
if (isTmp())
return value() == other.value();
return virtualRegister() == other.virtualRegister();
}
inline bool Operand::isValid() const
{
if (isTmp())
return value() >= 0;
return virtualRegister().isValid();
}
inline Operand Operand::fromBits(uint64_t value)
{
Operand result = bitwise_cast<Operand>(value);
ASSERT(result.isValid());
return result;
}
static_assert(sizeof(Operand) == sizeof(uint64_t), "Operand::asBits() relies on this.");
enum OperandsLikeTag { OperandsLike };
template<typename T>
class Operands {
public:
using Storage = std::conditional_t<std::is_same_v<T, bool>, FastBitVector, Vector<T, 0, UnsafeVectorOverflow>>;
using RefType = std::conditional_t<std::is_same_v<T, bool>, FastBitReference, T&>;
using ConstRefType = std::conditional_t<std::is_same_v<T, bool>, bool, const T&>;
Operands() = default;
explicit Operands(size_t numArguments, size_t numLocals, size_t numTmps)
: m_numArguments(numArguments)
, m_numLocals(numLocals)
{
size_t size = numArguments + numLocals + numTmps;
m_values.grow(size);
if (!WTF::VectorTraits<T>::needsInitialization)
m_values.fill(T());
}
explicit Operands(size_t numArguments, size_t numLocals, size_t numTmps, const T& initialValue)
: m_numArguments(numArguments)
, m_numLocals(numLocals)
{
m_values.grow(numArguments + numLocals + numTmps);
m_values.fill(initialValue);
}
template<typename U>
explicit Operands(OperandsLikeTag, const Operands<U>& other, const T& initialValue = T())
: m_numArguments(other.numberOfArguments())
, m_numLocals(other.numberOfLocals())
{
m_values.grow(other.size());
m_values.fill(initialValue);
}
size_t numberOfArguments() const { return m_numArguments; }
size_t numberOfLocals() const { return m_numLocals; }
size_t numberOfTmps() const { return m_values.size() - numberOfArguments() - numberOfLocals(); }
size_t tmpIndex(size_t idx) const
{
ASSERT(idx < numberOfTmps());
return idx + numberOfArguments() + numberOfLocals();
}
size_t argumentIndex(size_t idx) const
{
ASSERT(idx < numberOfArguments());
return idx;
}
size_t localIndex(size_t idx) const
{
ASSERT(idx < numberOfLocals());
return numberOfArguments() + idx;
}
RefType tmp(size_t idx) { return m_values[tmpIndex(idx)]; }
ConstRefType tmp(size_t idx) const { return m_values[tmpIndex(idx)]; }
RefType argument(size_t idx) { return m_values[argumentIndex(idx)]; }
ConstRefType argument(size_t idx) const { return m_values[argumentIndex(idx)]; }
RefType local(size_t idx) { return m_values[localIndex(idx)]; }
ConstRefType local(size_t idx) const { return m_values[localIndex(idx)]; }
template<OperandKind operandKind>
size_t sizeFor() const
{
switch (operandKind) {
case OperandKind::Tmp:
return numberOfTmps();
case OperandKind::Argument:
return numberOfArguments();
case OperandKind::Local:
return numberOfLocals();
}
RELEASE_ASSERT_NOT_REACHED();
return 0;
}
template<OperandKind operandKind>
RefType atFor(size_t idx)
{
switch (operandKind) {
case OperandKind::Tmp:
return tmp(idx);
case OperandKind::Argument:
return argument(idx);
case OperandKind::Local:
return local(idx);
}
RELEASE_ASSERT_NOT_REACHED();
return tmp(0);
}
template<OperandKind operandKind>
ConstRefType atFor(size_t idx) const
{
switch (operandKind) {
case OperandKind::Tmp:
return tmp(idx);
case OperandKind::Argument:
return argument(idx);
case OperandKind::Local:
return local(idx);
}
RELEASE_ASSERT_NOT_REACHED();
return tmp(0);
}
void ensureLocals(size_t size, const T& ensuredValue = T())
{
if (size <= numberOfLocals())
return;
size_t newSize = numberOfArguments() + numberOfTmps() + size;
size_t oldNumLocals = numberOfLocals();
size_t oldNumTmps = numberOfTmps();
m_values.grow(newSize);
for (size_t i = 0; i < oldNumTmps; ++i)
m_values[newSize - 1 - i] = m_values[tmpIndex(oldNumTmps - 1 - i)];
m_numLocals = size;
if (ensuredValue != T() || !WTF::VectorTraits<T>::needsInitialization) {
for (size_t i = 0; i < size - oldNumLocals; ++i)
m_values[localIndex(oldNumLocals + i)] = ensuredValue;
}
}
void ensureTmps(size_t size, const T& ensuredValue = T())
{
if (size <= numberOfTmps())
return;
size_t oldSize = m_values.size();
size_t newSize = numberOfArguments() + numberOfLocals() + size;
m_values.grow(newSize);
if (ensuredValue != T() || !WTF::VectorTraits<T>::needsInitialization) {
for (size_t i = oldSize; i < newSize; ++i)
m_values[i] = ensuredValue;
}
}
void setLocal(size_t idx, const T& value)
{
ensureLocals(idx + 1);
local(idx) = value;
}
T getLocal(size_t idx)
{
return idx >= numberOfLocals() ? T() : local(idx);
}
void setArgumentFirstTime(size_t idx, const T& value)
{
ASSERT(m_values[idx] == T());
argument(idx) = value;
}
void setLocalFirstTime(size_t idx, const T& value)
{
ASSERT(idx >= numberOfLocals() || local(idx) == T());
setLocal(idx, value);
}
RefType getForOperandIndex(size_t index) { return m_values[index]; }
ConstRefType getForOperandIndex(size_t index) const { return const_cast<Operands*>(this)->getForOperandIndex(index); }
size_t operandIndex(VirtualRegister operand) const
{
if (operand.isArgument())
return argumentIndex(operand.toArgument());
return localIndex(operand.toLocal());
}
size_t operandIndex(Operand op) const
{
if (!op.isTmp())
return operandIndex(op.virtualRegister());
return tmpIndex(op.value());
}
RefType operand(VirtualRegister operand)
{
if (operand.isArgument())
return argument(operand.toArgument());
return local(operand.toLocal());
}
RefType operand(Operand op)
{
if (!op.isTmp())
return operand(op.virtualRegister());
return tmp(op.value());
}
ConstRefType operand(VirtualRegister operand) const { return const_cast<Operands*>(this)->operand(operand); }
ConstRefType operand(Operand operand) const { return const_cast<Operands*>(this)->operand(operand); }
bool hasOperand(VirtualRegister operand) const
{
if (operand.isArgument())
return true;
return static_cast<size_t>(operand.toLocal()) < numberOfLocals();
}
bool hasOperand(Operand op) const
{
if (op.isTmp()) {
ASSERT(op.value() >= 0);
return static_cast<size_t>(op.value()) < numberOfTmps();
}
return hasOperand(op.virtualRegister());
}
void setOperand(Operand operand, const T& value)
{
this->operand(operand) = value;
}
size_t size() const { return m_values.size(); }
ConstRefType at(size_t index) const { return m_values[index]; }
RefType at(size_t index) { return m_values[index]; }
ConstRefType operator[](size_t index) const { return at(index); }
RefType operator[](size_t index) { return at(index); }
Operand operandForIndex(size_t index) const
{
if (index < numberOfArguments())
return virtualRegisterForArgumentIncludingThis(index);
else if (index < numberOfLocals() + numberOfArguments())
return virtualRegisterForLocal(index - numberOfArguments());
return Operand::tmp(index - (numberOfLocals() + numberOfArguments()));
}
void fill(T value)
{
for (size_t i = 0; i < m_values.size(); ++i)
m_values[i] = value;
}
void clear()
{
fill(T());
}
bool operator==(const Operands& other) const
{
ASSERT(numberOfArguments() == other.numberOfArguments());
ASSERT(numberOfLocals() == other.numberOfLocals());
ASSERT(numberOfTmps() == other.numberOfTmps());
return m_values == other.m_values;
}
void dumpInContext(PrintStream& out, DumpContext* context) const;
void dump(PrintStream& out) const;
private:
// The first m_numArguments of m_values are arguments, the next m_numLocals are locals, and the rest are tmps.
Storage m_values;
unsigned m_numArguments { 0 };
unsigned m_numLocals { 0 };
};
} // namespace JSC