| /* | 
 |  * Copyright (C) 2011-2019 Apple Inc. All rights reserved. | 
 |  * | 
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 |  * 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 | 
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 |  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  | 
 |  */ | 
 |  | 
 | #pragma once | 
 |  | 
 | #include "CallFrame.h" | 
 | #include "VirtualRegister.h" | 
 |  | 
 | #include <wtf/FixedVector.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); } | 
 |  | 
 |     Operand& operator=(const Operand&) = default; | 
 |  | 
 |     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, typename StorageArg = std::conditional_t<std::is_same_v<T, bool>, FastBitVector, Vector<T, 0, UnsafeVectorOverflow>>> | 
 | class Operands { | 
 | public: | 
 |     template<typename, typename> friend class Operands; | 
 |  | 
 |     using Storage = StorageArg; | 
 |     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_values(numArguments + numLocals + numTmps) | 
 |         , m_numArguments(numArguments) | 
 |         , m_numLocals(numLocals) | 
 |     { | 
 |         if (!WTF::VectorTraits<T>::needsInitialization) | 
 |             m_values.fill(T()); | 
 |     } | 
 |  | 
 |     explicit Operands(size_t numArguments, size_t numLocals, size_t numTmps, const T& initialValue) | 
 |         : m_values(numArguments + numLocals + numTmps) | 
 |         , m_numArguments(numArguments) | 
 |         , m_numLocals(numLocals) | 
 |     { | 
 |         m_values.fill(initialValue); | 
 |     } | 
 |      | 
 |     template<typename U, typename V> | 
 |     explicit Operands(OperandsLikeTag, const Operands<U, V>& other, const T& initialValue = T()) | 
 |         : m_values(other.size()) | 
 |         , m_numArguments(other.numberOfArguments()) | 
 |         , m_numLocals(other.numberOfLocals()) | 
 |     { | 
 |         m_values.fill(initialValue); | 
 |     } | 
 |  | 
 |     template<typename U> | 
 |     explicit Operands(const Operands<T, U>& other) | 
 |         : m_values(other.m_values) | 
 |         , m_numArguments(other.m_numArguments) | 
 |         , m_numLocals(other.m_numLocals) | 
 |     { | 
 |     } | 
 |  | 
 |     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; | 
 |     } | 
 |  | 
 |     bool operator!=(const Operands& other) const | 
 |     { | 
 |         return !(*this == other); | 
 |     } | 
 |      | 
 |     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 }; | 
 | }; | 
 |  | 
 | template<typename T> | 
 | using FixedOperands = Operands<T, std::conditional_t<std::is_same_v<T, bool>, FastBitVector, FixedVector<T>>>; | 
 |  | 
 | } // namespace JSC |