jitarithmetic.cpp

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    addSlowCase(branchSub32(Zero, Imm32(1), regT0));
    emitFastArithIntToImmNoCheck(regT0, regT0);
#else
    addSlowCase(branchSub32(Zero, Imm32(1 << JSImmediate::IntegerPayloadShift), regT0));
    signExtend32ToPtr(regT0, regT0);
#endif
    emitPutVirtualRegister(srcDst);
}
void JIT::compileFastArithSlow_op_pre_dec(unsigned srcDst, Vector<SlowCaseEntry>::iterator& iter)
{
    Jump notImm = getSlowCase(iter);
    linkSlowCase(iter);
    emitGetVirtualRegister(srcDst, regT0);
    notImm.link(this);
    emitPutJITStubArg(regT0, 1);
    emitCTICall(JITStubs::cti_op_pre_dec);
    emitPutVirtualRegister(srcDst);
}


#if !ENABLE(JIT_OPTIMIZE_ARITHMETIC)

void JIT::compileFastArith_op_add(Instruction* currentInstruction)
{
    unsigned result = currentInstruction[1].u.operand;
    unsigned op1 = currentInstruction[2].u.operand;
    unsigned op2 = currentInstruction[3].u.operand;

    emitPutJITStubArgFromVirtualRegister(op1, 1, regT2);
    emitPutJITStubArgFromVirtualRegister(op2, 2, regT2);
    emitCTICall(JITStubs::cti_op_add);
    emitPutVirtualRegister(result);
}
void JIT::compileFastArithSlow_op_add(Instruction*, Vector<SlowCaseEntry>::iterator&)
{
    ASSERT_NOT_REACHED();
}

void JIT::compileFastArith_op_mul(Instruction* currentInstruction)
{
    unsigned result = currentInstruction[1].u.operand;
    unsigned op1 = currentInstruction[2].u.operand;
    unsigned op2 = currentInstruction[3].u.operand;

    emitPutJITStubArgFromVirtualRegister(op1, 1, regT2);
    emitPutJITStubArgFromVirtualRegister(op2, 2, regT2);
    emitCTICall(JITStubs::cti_op_mul);
    emitPutVirtualRegister(result);
}
void JIT::compileFastArithSlow_op_mul(Instruction*, Vector<SlowCaseEntry>::iterator&)
{
    ASSERT_NOT_REACHED();
}

void JIT::compileFastArith_op_sub(Instruction* currentInstruction)
{
    unsigned result = currentInstruction[1].u.operand;
    unsigned op1 = currentInstruction[2].u.operand;
    unsigned op2 = currentInstruction[3].u.operand;

    emitPutJITStubArgFromVirtualRegister(op1, 1, regT2);
    emitPutJITStubArgFromVirtualRegister(op2, 2, regT2);
    emitCTICall(JITStubs::cti_op_sub);
    emitPutVirtualRegister(result);
}
void JIT::compileFastArithSlow_op_sub(Instruction*, Vector<SlowCaseEntry>::iterator&)
{
    ASSERT_NOT_REACHED();
}

#elif USE(ALTERNATE_JSIMMEDIATE) // *AND* ENABLE(JIT_OPTIMIZE_ARITHMETIC)

void JIT::compileBinaryArithOp(OpcodeID opcodeID, unsigned, unsigned op1, unsigned op2, OperandTypes)
{
    emitGetVirtualRegisters(op1, X86::eax, op2, X86::edx);
    emitJumpSlowCaseIfNotImmediateInteger(X86::eax);
    emitJumpSlowCaseIfNotImmediateInteger(X86::edx);
    if (opcodeID == op_add)
        addSlowCase(branchAdd32(Overflow, X86::edx, X86::eax));
    else if (opcodeID == op_sub)
        addSlowCase(branchSub32(Overflow, X86::edx, X86::eax));
    else {
        ASSERT(opcodeID == op_mul);
        addSlowCase(branchMul32(Overflow, X86::edx, X86::eax));
        addSlowCase(branchTest32(Zero, X86::eax));
    }
    emitFastArithIntToImmNoCheck(X86::eax, X86::eax);
}

void JIT::compileBinaryArithOpSlowCase(OpcodeID opcodeID, Vector<SlowCaseEntry>::iterator& iter, unsigned, unsigned op1, unsigned, OperandTypes types)
{
    // We assume that subtracting TagTypeNumber is equivalent to adding DoubleEncodeOffset.
    COMPILE_ASSERT(((JSImmediate::TagTypeNumber + JSImmediate::DoubleEncodeOffset) == 0), TagTypeNumber_PLUS_DoubleEncodeOffset_EQUALS_0);

    Jump notImm1 = getSlowCase(iter);
    Jump notImm2 = getSlowCase(iter);

    linkSlowCase(iter); // Integer overflow case - we could handle this in JIT code, but this is likely rare.
    if (opcodeID == op_mul) // op_mul has an extra slow case to handle 0 * negative number.
        linkSlowCase(iter);
    emitGetVirtualRegister(op1, X86::eax);

    Label stubFunctionCall(this);
    emitPutJITStubArg(X86::eax, 1);
    emitPutJITStubArg(X86::edx, 2);
    if (opcodeID == op_add)
        emitCTICall(JITStubs::cti_op_add);
    else if (opcodeID == op_sub)
        emitCTICall(JITStubs::cti_op_sub);
    else {
        ASSERT(opcodeID == op_mul);
        emitCTICall(JITStubs::cti_op_mul);
    }
    Jump end = jump();

    // if we get here, eax is not an int32, edx not yet checked.
    notImm1.link(this);
    if (!types.first().definitelyIsNumber())
        emitJumpIfNotImmediateNumber(X86::eax).linkTo(stubFunctionCall, this);
    if (!types.second().definitelyIsNumber())
        emitJumpIfNotImmediateNumber(X86::edx).linkTo(stubFunctionCall, this);
    addPtr(tagTypeNumberRegister, X86::eax);
    m_assembler.movq_rr(X86::eax, X86::xmm1);
    Jump op2isDouble = emitJumpIfNotImmediateInteger(X86::edx);
    m_assembler.cvtsi2sd_rr(X86::edx, X86::xmm2);
    Jump op2wasInteger = jump();

    // if we get here, eax IS an int32, edx is not.
    notImm2.link(this);
    if (!types.second().definitelyIsNumber())
        emitJumpIfNotImmediateNumber(X86::edx).linkTo(stubFunctionCall, this);
    m_assembler.cvtsi2sd_rr(X86::eax, X86::xmm1);
    op2isDouble.link(this);
    addPtr(tagTypeNumberRegister, X86::edx);
    m_assembler.movq_rr(X86::edx, X86::xmm2);
    op2wasInteger.link(this);

    if (opcodeID == op_add)
        m_assembler.addsd_rr(X86::xmm2, X86::xmm1);
    else if (opcodeID == op_sub)
        m_assembler.subsd_rr(X86::xmm2, X86::xmm1);
    else {
        ASSERT(opcodeID == op_mul);
        m_assembler.mulsd_rr(X86::xmm2, X86::xmm1);
    }
    m_assembler.movq_rr(X86::xmm1, X86::eax);
    subPtr(tagTypeNumberRegister, X86::eax);

    end.link(this);
}

void JIT::compileFastArith_op_add(Instruction* currentInstruction)
{
    unsigned result = currentInstruction[1].u.operand;
    unsigned op1 = currentInstruction[2].u.operand;
    unsigned op2 = currentInstruction[3].u.operand;
    OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);

    if (!types.first().mightBeNumber() || !types.second().mightBeNumber()) {
        emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
        emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
        emitCTICall(JITStubs::cti_op_add);
        emitPutVirtualRegister(result);
        return;
    }

    if (isOperandConstantImmediateInt(op1)) {
        emitGetVirtualRegister(op2, X86::eax);
        emitJumpSlowCaseIfNotImmediateInteger(X86::eax);
        addSlowCase(branchAdd32(Overflow, Imm32(getConstantOperandImmediateInt(op1)), X86::eax));
        emitFastArithIntToImmNoCheck(X86::eax, X86::eax);
    } else if (isOperandConstantImmediateInt(op2)) {
        emitGetVirtualRegister(op1, X86::eax);
        emitJumpSlowCaseIfNotImmediateInteger(X86::eax);
        addSlowCase(branchAdd32(Overflow, Imm32(getConstantOperandImmediateInt(op2)), X86::eax));
        emitFastArithIntToImmNoCheck(X86::eax, X86::eax);
    } else
        compileBinaryArithOp(op_add, result, op1, op2, types);

    emitPutVirtualRegister(result);
}
void JIT::compileFastArithSlow_op_add(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
{
    unsigned result = currentInstruction[1].u.operand;
    unsigned op1 = currentInstruction[2].u.operand;
    unsigned op2 = currentInstruction[3].u.operand;
    OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);

    if (isOperandConstantImmediateInt(op1)) {
        linkSlowCase(iter);
        linkSlowCase(iter);
        emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
        emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
        emitCTICall(JITStubs::cti_op_add);
    } else if (isOperandConstantImmediateInt(op2)) {
        linkSlowCase(iter);
        linkSlowCase(iter);
        emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
        emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
        emitCTICall(JITStubs::cti_op_add);
    } else
        compileBinaryArithOpSlowCase(op_add, iter, result, op1, op2, types);

    emitPutVirtualRegister(result);
}

void JIT::compileFastArith_op_mul(Instruction* currentInstruction)
{
    unsigned result = currentInstruction[1].u.operand;
    unsigned op1 = currentInstruction[2].u.operand;
    unsigned op2 = currentInstruction[3].u.operand;
    OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);

    // For now, only plant a fast int case if the constant operand is greater than zero.
    int32_t value;
    if (isOperandConstantImmediateInt(op1) && ((value = getConstantOperandImmediateInt(op1)) > 0)) {
        emitGetVirtualRegister(op2, X86::eax);
        emitJumpSlowCaseIfNotImmediateInteger(X86::eax);
        addSlowCase(branchMul32(Overflow, Imm32(value), X86::eax, X86::eax));
        emitFastArithReTagImmediate(X86::eax, X86::eax);
    } else if (isOperandConstantImmediateInt(op2) && ((value = getConstantOperandImmediateInt(op2)) > 0)) {
        emitGetVirtualRegister(op1, X86::eax);
        emitJumpSlowCaseIfNotImmediateInteger(X86::eax);
        addSlowCase(branchMul32(Overflow, Imm32(value), X86::eax, X86::eax));
        emitFastArithReTagImmediate(X86::eax, X86::eax);
    } else
        compileBinaryArithOp(op_mul, result, op1, op2, types);

    emitPutVirtualRegister(result);
}
void JIT::compileFastArithSlow_op_mul(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
{
    unsigned result = currentInstruction[1].u.operand;
    unsigned op1 = currentInstruction[2].u.operand;
    unsigned op2 = currentInstruction[3].u.operand;
    OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);

    if ((isOperandConstantImmediateInt(op1) && (getConstantOperandImmediateInt(op1) > 0))
        || (isOperandConstantImmediateInt(op2) && (getConstantOperandImmediateInt(op2) > 0))) {
        linkSlowCase(iter);
        linkSlowCase(iter);
        // There is an extra slow case for (op1 * -N) or (-N * op2), to check for 0 since this should produce a result of -0.
        emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
        emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
        emitCTICall(JITStubs::cti_op_mul);
    } else
        compileBinaryArithOpSlowCase(op_mul, iter, result, op1, op2, types);

    emitPutVirtualRegister(result);
}

void JIT::compileFastArith_op_sub(Instruction* currentInstruction)
{
    unsigned result = currentInstruction[1].u.operand;
    unsigned op1 = currentInstruction[2].u.operand;
    unsigned op2 = currentInstruction[3].u.operand;
    OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);

    compileBinaryArithOp(op_sub, result, op1, op2, types);

    emitPutVirtualRegister(result);
}
void JIT::compileFastArithSlow_op_sub(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
{
    unsigned result = currentInstruction[1].u.operand;
    unsigned op1 = currentInstruction[2].u.operand;
    unsigned op2 = currentInstruction[3].u.operand;
    OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);

    compileBinaryArithOpSlowCase(op_sub, iter, result, op1, op2, types);

    emitPutVirtualRegister(result);
}

#else

typedef X86Assembler::JmpSrc JmpSrc;
typedef X86Assembler::JmpDst JmpDst;
typedef X86Assembler::XMMRegisterID XMMRegisterID;

#if PLATFORM(MAC)

static inline bool isSSE2Present()
{
    return true; // All X86 Macs are guaranteed to support at least SSE2
}

#else

static bool isSSE2Present()
{
    static const int SSE2FeatureBit = 1 << 26;
    struct SSE2Check {
        SSE2Check()
        {
            int flags;
#if COMPILER(MSVC)
            _asm {
                mov eax, 1 // cpuid function 1 gives us the standard feature set
                cpuid;
                mov flags, edx;
            }
#elif COMPILER(GCC)
            asm (
                "movl $0x1, %%eax;"
                "pushl %%ebx;"
                "cpuid;"
                "popl %%ebx;"
                "movl %%edx, %0;"
                : "=g" (flags)
                :
                : "%eax", "%ecx", "%edx"
            );
#else
            flags = 0;
#endif
            present = (flags & SSE2FeatureBit) != 0;
        }
        bool present;
    };
    static SSE2Check check;