| /* |
| * Copyright (C) 2015-2018 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 |
| |
| #if ENABLE(B3_JIT) |
| |
| #include "FPRInfo.h" |
| #include "GPRInfo.h" |
| #include "JSCJSValue.h" |
| #include "Reg.h" |
| #include "RegisterSet.h" |
| #include "ValueRecovery.h" |
| #include <wtf/PrintStream.h> |
| |
| namespace JSC { |
| |
| class AssemblyHelpers; |
| |
| namespace B3 { |
| |
| // We use this class to describe value representations at stackmaps. It's used both to force a |
| // representation and to get the representation. When the B3 client forces a representation, we say |
| // that it's an input. When B3 tells the client what representation it picked, we say that it's an |
| // output. |
| |
| class ValueRep { |
| public: |
| enum Kind { |
| // As an input representation, this means that B3 can pick any representation. As an output |
| // representation, this means that we don't know. This will only arise as an output |
| // representation for the active arguments of Check/CheckAdd/CheckSub/CheckMul. |
| WarmAny, |
| |
| // Same as WarmAny, but implies that the use is cold. A cold use is not counted as a use for |
| // computing the priority of the used temporary. |
| ColdAny, |
| |
| // Same as ColdAny, but also implies that the use occurs after all other effects of the stackmap |
| // value. |
| LateColdAny, |
| |
| // As an input representation, this means that B3 should pick some register. It could be a |
| // register that this claims to clobber! |
| SomeRegister, |
| |
| // As an input representation, this means that B3 should pick some register but that this |
| // register is then cobbered with garbage. This only works for patchpoints. |
| SomeRegisterWithClobber, |
| |
| // As an input representation, this tells us that B3 should pick some register, but implies |
| // that the def happens before any of the effects of the stackmap. This is only valid for |
| // the result constraint of a Patchpoint. |
| SomeEarlyRegister, |
| |
| // As an input representation, this forces a particular register. As an output |
| // representation, this tells us what register B3 picked. |
| Register, |
| |
| // As an input representation, this forces a particular register and states that |
| // the register is used late. This means that the register is used after the result |
| // is defined (i.e, the result will interfere with this as an input). |
| // It's not a valid output representation. |
| LateRegister, |
| |
| // As an output representation, this tells us what stack slot B3 picked. It's not a valid |
| // input representation. |
| Stack, |
| |
| // As an input representation, this forces the value to end up in the argument area at some |
| // offset. |
| StackArgument, |
| |
| // As an output representation, this tells us that B3 constant-folded the value. |
| Constant |
| }; |
| |
| ValueRep() |
| : m_kind(WarmAny) |
| { |
| } |
| |
| explicit ValueRep(Reg reg) |
| : m_kind(Register) |
| { |
| u.reg = reg; |
| } |
| |
| ValueRep(Kind kind) |
| : m_kind(kind) |
| { |
| ASSERT(kind == WarmAny || kind == ColdAny || kind == LateColdAny || kind == SomeRegister || kind == SomeRegisterWithClobber || kind == SomeEarlyRegister); |
| } |
| |
| static ValueRep reg(Reg reg) |
| { |
| return ValueRep(reg); |
| } |
| |
| static ValueRep lateReg(Reg reg) |
| { |
| ValueRep result(reg); |
| result.m_kind = LateRegister; |
| return result; |
| } |
| |
| static ValueRep stack(intptr_t offsetFromFP) |
| { |
| ValueRep result; |
| result.m_kind = Stack; |
| result.u.offsetFromFP = offsetFromFP; |
| return result; |
| } |
| |
| static ValueRep stackArgument(intptr_t offsetFromSP) |
| { |
| ValueRep result; |
| result.m_kind = StackArgument; |
| result.u.offsetFromSP = offsetFromSP; |
| return result; |
| } |
| |
| static ValueRep constant(int64_t value) |
| { |
| ValueRep result; |
| result.m_kind = Constant; |
| result.u.value = value; |
| return result; |
| } |
| |
| static ValueRep constantDouble(double value) |
| { |
| return ValueRep::constant(bitwise_cast<int64_t>(value)); |
| } |
| |
| Kind kind() const { return m_kind; } |
| |
| bool operator==(const ValueRep& other) const |
| { |
| if (kind() != other.kind()) |
| return false; |
| switch (kind()) { |
| case LateRegister: |
| case Register: |
| return u.reg == other.u.reg; |
| case Stack: |
| return u.offsetFromFP == other.u.offsetFromFP; |
| case StackArgument: |
| return u.offsetFromSP == other.u.offsetFromSP; |
| case Constant: |
| return u.value == other.u.value; |
| default: |
| return true; |
| } |
| } |
| |
| bool operator!=(const ValueRep& other) const |
| { |
| return !(*this == other); |
| } |
| |
| explicit operator bool() const { return kind() != WarmAny; } |
| |
| bool isAny() const { return kind() == WarmAny || kind() == ColdAny || kind() == LateColdAny; } |
| |
| bool isReg() const { return kind() == Register || kind() == LateRegister; } |
| |
| Reg reg() const |
| { |
| ASSERT(isReg()); |
| return u.reg; |
| } |
| |
| bool isGPR() const { return isReg() && reg().isGPR(); } |
| bool isFPR() const { return isReg() && reg().isFPR(); } |
| |
| GPRReg gpr() const { return reg().gpr(); } |
| FPRReg fpr() const { return reg().fpr(); } |
| |
| bool isStack() const { return kind() == Stack; } |
| |
| intptr_t offsetFromFP() const |
| { |
| ASSERT(isStack()); |
| return u.offsetFromFP; |
| } |
| |
| bool isStackArgument() const { return kind() == StackArgument; } |
| |
| intptr_t offsetFromSP() const |
| { |
| ASSERT(isStackArgument()); |
| return u.offsetFromSP; |
| } |
| |
| bool isConstant() const { return kind() == Constant; } |
| |
| int64_t value() const |
| { |
| ASSERT(isConstant()); |
| return u.value; |
| } |
| |
| double doubleValue() const |
| { |
| return bitwise_cast<double>(value()); |
| } |
| |
| ValueRep withOffset(intptr_t offset) const |
| { |
| switch (kind()) { |
| case Stack: |
| return stack(offsetFromFP() + offset); |
| case StackArgument: |
| return stackArgument(offsetFromSP() + offset); |
| default: |
| return *this; |
| } |
| } |
| |
| void addUsedRegistersTo(RegisterSet&) const; |
| |
| RegisterSet usedRegisters() const; |
| |
| // Get the used registers for a vector of ValueReps. |
| template<typename VectorType> |
| static RegisterSet usedRegisters(const VectorType& vector) |
| { |
| RegisterSet result; |
| for (const ValueRep& value : vector) |
| value.addUsedRegistersTo(result); |
| return result; |
| } |
| |
| JS_EXPORT_PRIVATE void dump(PrintStream&) const; |
| |
| // This has a simple contract: it emits code to restore the value into the given register. This |
| // will work even if it requires moving between bits a GPR and a FPR. |
| void emitRestore(AssemblyHelpers&, Reg) const; |
| |
| // Computes the ValueRecovery assuming that the Value* was for a JSValue (i.e. Int64). |
| // NOTE: We should avoid putting JSValue-related methods in B3, but this was hard to avoid |
| // because some parts of JSC use ValueRecovery like a general "where my bits at" object, almost |
| // exactly like ValueRep. |
| ValueRecovery recoveryForJSValue() const; |
| |
| private: |
| Kind m_kind; |
| union U { |
| Reg reg; |
| intptr_t offsetFromFP; |
| intptr_t offsetFromSP; |
| int64_t value; |
| |
| U() |
| { |
| memset(this, 0, sizeof(*this)); |
| } |
| } u; |
| }; |
| |
| } } // namespace JSC::B3 |
| |
| namespace WTF { |
| |
| void printInternal(PrintStream&, JSC::B3::ValueRep::Kind); |
| |
| } // namespace WTF |
| |
| #endif // ENABLE(B3_JIT) |