jitarithmetic.cpp

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    return check.present;
}

#endif

void JIT::compileBinaryArithOp(OpcodeID opcodeID, unsigned dst, unsigned src1, unsigned src2, OperandTypes types)
{
    Structure* numberStructure = m_globalData->numberStructure.get();
    JmpSrc wasJSNumberCell1;
    JmpSrc wasJSNumberCell2;

    emitGetVirtualRegisters(src1, X86::eax, src2, X86::edx);

    if (types.second().isReusable() && isSSE2Present()) {
        ASSERT(types.second().mightBeNumber());

        // Check op2 is a number
        __ testl_i32r(JSImmediate::TagTypeNumber, X86::edx);
        JmpSrc op2imm = __ jne();
        if (!types.second().definitelyIsNumber()) {
            emitJumpSlowCaseIfNotJSCell(X86::edx, src2);
            __ cmpl_im(reinterpret_cast<unsigned>(numberStructure), FIELD_OFFSET(JSCell, m_structure), X86::edx);
            addSlowCase(__ jne());
        }

        // (1) In this case src2 is a reusable number cell.
        //     Slow case if src1 is not a number type.
        __ testl_i32r(JSImmediate::TagTypeNumber, X86::eax);
        JmpSrc op1imm = __ jne();
        if (!types.first().definitelyIsNumber()) {
            emitJumpSlowCaseIfNotJSCell(X86::eax, src1);
            __ cmpl_im(reinterpret_cast<unsigned>(numberStructure), FIELD_OFFSET(JSCell, m_structure), X86::eax);
            addSlowCase(__ jne());
        }

        // (1a) if we get here, src1 is also a number cell
        __ movsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::eax, X86::xmm0);
        JmpSrc loadedDouble = __ jmp();
        // (1b) if we get here, src1 is an immediate
        __ linkJump(op1imm, __ label());
        emitFastArithImmToInt(X86::eax);
        __ cvtsi2sd_rr(X86::eax, X86::xmm0);
        // (1c) 
        __ linkJump(loadedDouble, __ label());
        if (opcodeID == op_add)
            __ addsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::edx, X86::xmm0);
        else if (opcodeID == op_sub)
            __ subsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::edx, X86::xmm0);
        else {
            ASSERT(opcodeID == op_mul);
            __ mulsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::edx, X86::xmm0);
        }

        // Store the result to the JSNumberCell and jump.
        __ movsd_rm(X86::xmm0, FIELD_OFFSET(JSNumberCell, m_value), X86::edx);
        __ movl_rr(X86::edx, X86::eax);
        emitPutVirtualRegister(dst);
        wasJSNumberCell2 = __ jmp();

        // (2) This handles cases where src2 is an immediate number.
        //     Two slow cases - either src1 isn't an immediate, or the subtract overflows.
        __ linkJump(op2imm, __ label());
        emitJumpSlowCaseIfNotImmediateInteger(X86::eax);
    } else if (types.first().isReusable() && isSSE2Present()) {
        ASSERT(types.first().mightBeNumber());

        // Check op1 is a number
        __ testl_i32r(JSImmediate::TagTypeNumber, X86::eax);
        JmpSrc op1imm = __ jne();
        if (!types.first().definitelyIsNumber()) {
            emitJumpSlowCaseIfNotJSCell(X86::eax, src1);
            __ cmpl_im(reinterpret_cast<unsigned>(numberStructure), FIELD_OFFSET(JSCell, m_structure), X86::eax);
            addSlowCase(__ jne());
        }

        // (1) In this case src1 is a reusable number cell.
        //     Slow case if src2 is not a number type.
        __ testl_i32r(JSImmediate::TagTypeNumber, X86::edx);
        JmpSrc op2imm = __ jne();
        if (!types.second().definitelyIsNumber()) {
            emitJumpSlowCaseIfNotJSCell(X86::edx, src2);
            __ cmpl_im(reinterpret_cast<unsigned>(numberStructure), FIELD_OFFSET(JSCell, m_structure), X86::edx);
            addSlowCase(__ jne());
        }

        // (1a) if we get here, src2 is also a number cell
        __ movsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::edx, X86::xmm1);
        JmpSrc loadedDouble = __ jmp();
        // (1b) if we get here, src2 is an immediate
        __ linkJump(op2imm, __ label());
        emitFastArithImmToInt(X86::edx);
        __ cvtsi2sd_rr(X86::edx, X86::xmm1);
        // (1c) 
        __ linkJump(loadedDouble, __ label());
        __ movsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::eax, X86::xmm0);
        if (opcodeID == op_add)
            __ addsd_rr(X86::xmm1, X86::xmm0);
        else if (opcodeID == op_sub)
            __ subsd_rr(X86::xmm1, X86::xmm0);
        else {
            ASSERT(opcodeID == op_mul);
            __ mulsd_rr(X86::xmm1, X86::xmm0);
        }
        __ movsd_rm(X86::xmm0, FIELD_OFFSET(JSNumberCell, m_value), X86::eax);
        emitPutVirtualRegister(dst);

        // Store the result to the JSNumberCell and jump.
        __ movsd_rm(X86::xmm0, FIELD_OFFSET(JSNumberCell, m_value), X86::eax);
        emitPutVirtualRegister(dst);
        wasJSNumberCell1 = __ jmp();

        // (2) This handles cases where src1 is an immediate number.
        //     Two slow cases - either src2 isn't an immediate, or the subtract overflows.
        __ linkJump(op1imm, __ label());
        emitJumpSlowCaseIfNotImmediateInteger(X86::edx);
    } else
        emitJumpSlowCaseIfNotImmediateIntegers(X86::eax, X86::edx, X86::ecx);

    if (opcodeID == op_add) {
        emitFastArithDeTagImmediate(X86::eax);
        __ addl_rr(X86::edx, X86::eax);
        addSlowCase(__ jo());
    } else  if (opcodeID == op_sub) {
        __ subl_rr(X86::edx, X86::eax);
        addSlowCase(__ jo());
        signExtend32ToPtr(X86::eax, X86::eax);
        emitFastArithReTagImmediate(X86::eax, X86::eax);
    } else {
        ASSERT(opcodeID == op_mul);
        // convert eax & edx from JSImmediates to ints, and check if either are zero
        emitFastArithImmToInt(X86::edx);
        Jump op1Zero = emitFastArithDeTagImmediateJumpIfZero(X86::eax);
        __ testl_rr(X86::edx, X86::edx);
        JmpSrc op2NonZero = __ jne();
        op1Zero.link(this);
        // if either input is zero, add the two together, and check if the result is < 0.
        // If it is, we have a problem (N < 0), (N * 0) == -0, not representatble as a JSImmediate. 
        __ movl_rr(X86::eax, X86::ecx);
        __ addl_rr(X86::edx, X86::ecx);
        addSlowCase(__ js());
        // Skip the above check if neither input is zero
        __ linkJump(op2NonZero, __ label());
        __ imull_rr(X86::edx, X86::eax);
        addSlowCase(__ jo());
        signExtend32ToPtr(X86::eax, X86::eax);
        emitFastArithReTagImmediate(X86::eax, X86::eax);
    }
    emitPutVirtualRegister(dst);

    if (types.second().isReusable() && isSSE2Present()) {
        __ linkJump(wasJSNumberCell2, __ label());
    }
    else if (types.first().isReusable() && isSSE2Present()) {
        __ linkJump(wasJSNumberCell1, __ label());
    }
}

void JIT::compileBinaryArithOpSlowCase(OpcodeID opcodeID, Vector<SlowCaseEntry>::iterator& iter, unsigned dst, unsigned src1, unsigned src2, OperandTypes types)
{
    linkSlowCase(iter);
    if (types.second().isReusable() && isSSE2Present()) {
        if (!types.first().definitelyIsNumber()) {
            linkSlowCaseIfNotJSCell(iter, src1);
            linkSlowCase(iter);
        }
        if (!types.second().definitelyIsNumber()) {
            linkSlowCaseIfNotJSCell(iter, src2);
            linkSlowCase(iter);
        }
    } else if (types.first().isReusable() && isSSE2Present()) {
        if (!types.first().definitelyIsNumber()) {
            linkSlowCaseIfNotJSCell(iter, src1);
            linkSlowCase(iter);
        }
        if (!types.second().definitelyIsNumber()) {
            linkSlowCaseIfNotJSCell(iter, src2);
            linkSlowCase(iter);
        }
    }
    linkSlowCase(iter);

    // additional entry point to handle -0 cases.
    if (opcodeID == op_mul)
        linkSlowCase(iter);

    emitPutJITStubArgFromVirtualRegister(src1, 1, X86::ecx);
    emitPutJITStubArgFromVirtualRegister(src2, 2, X86::ecx);
    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);
    }
    emitPutVirtualRegister(dst);
}

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;

    if (isOperandConstantImmediateInt(op1)) {
        emitGetVirtualRegister(op2, X86::eax);
        emitJumpSlowCaseIfNotImmediateInteger(X86::eax);
        addSlowCase(branchAdd32(Overflow, Imm32(getConstantOperandImmediateInt(op1) << JSImmediate::IntegerPayloadShift), X86::eax));
        signExtend32ToPtr(X86::eax, X86::eax);
        emitPutVirtualRegister(result);
    } else if (isOperandConstantImmediateInt(op2)) {
        emitGetVirtualRegister(op1, X86::eax);
        emitJumpSlowCaseIfNotImmediateInteger(X86::eax);
        addSlowCase(branchAdd32(Overflow, Imm32(getConstantOperandImmediateInt(op2) << JSImmediate::IntegerPayloadShift), X86::eax));
        signExtend32ToPtr(X86::eax, X86::eax);
        emitPutVirtualRegister(result);
    } else {
        OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);
        if (types.first().mightBeNumber() && types.second().mightBeNumber())
            compileBinaryArithOp(op_add, result, op1, op2, OperandTypes::fromInt(currentInstruction[4].u.operand));
        else {
            emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
            emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
            emitCTICall(JITStubs::cti_op_add);
            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;

    if (isOperandConstantImmediateInt(op1)) {
        Jump notImm = getSlowCase(iter);
        linkSlowCase(iter);
        sub32(Imm32(getConstantOperandImmediateInt(op1) << JSImmediate::IntegerPayloadShift), X86::eax);
        notImm.link(this);
        emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
        emitPutJITStubArg(X86::eax, 2);
        emitCTICall(JITStubs::cti_op_add);
        emitPutVirtualRegister(result);
    } else if (isOperandConstantImmediateInt(op2)) {
        Jump notImm = getSlowCase(iter);
        linkSlowCase(iter);
        sub32(Imm32(getConstantOperandImmediateInt(op2) << JSImmediate::IntegerPayloadShift), X86::eax);
        notImm.link(this);
        emitPutJITStubArg(X86::eax, 1);
        emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
        emitCTICall(JITStubs::cti_op_add);
        emitPutVirtualRegister(result);
    } else {
        OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);
        ASSERT(types.first().mightBeNumber() && types.second().mightBeNumber());
        compileBinaryArithOpSlowCase(op_add, iter, result, op1, op2, types);
    }
}

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;

    // 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);
        emitFastArithDeTagImmediate(X86::eax);
        addSlowCase(branchMul32(Overflow, Imm32(value), X86::eax, X86::eax));
        signExtend32ToPtr(X86::eax, X86::eax);
        emitFastArithReTagImmediate(X86::eax, X86::eax);
        emitPutVirtualRegister(result);
    } else if (isOperandConstantImmediateInt(op2) && ((value = getConstantOperandImmediateInt(op2)) > 0)) {
        emitGetVirtualRegister(op1, X86::eax);
        emitJumpSlowCaseIfNotImmediateInteger(X86::eax);
        emitFastArithDeTagImmediate(X86::eax);
        addSlowCase(branchMul32(Overflow, Imm32(value), X86::eax, X86::eax));
        signExtend32ToPtr(X86::eax, X86::eax);
        emitFastArithReTagImmediate(X86::eax, X86::eax);
        emitPutVirtualRegister(result);
    } else
        compileBinaryArithOp(op_mul, result, op1, op2, OperandTypes::fromInt(currentInstruction[4].u.operand));
}
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;

    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);
        emitPutVirtualRegister(result);
    } else
        compileBinaryArithOpSlowCase(op_mul, iter, result, op1, op2, OperandTypes::fromInt(currentInstruction[4].u.operand));
}

void JIT::compileFastArith_op_sub(Instruction* currentInstruction)
{
    compileBinaryArithOp(op_sub, currentInstruction[1].u.operand, currentInstruction[2].u.operand, currentInstruction[3].u.operand, OperandTypes::fromInt(currentInstruction[4].u.operand));
}
void JIT::compileFastArithSlow_op_sub(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
{
    compileBinaryArithOpSlowCase(op_sub, iter, currentInstruction[1].u.operand, currentInstruction[2].u.operand, currentInstruction[3].u.operand, OperandTypes::fromInt(currentInstruction[4].u.operand));
}

#endif

} // namespace JSC

#endif // ENABLE(JIT)