// The OS/K Team licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

#include <in/instrs.h>

//----------------------------------------------------------------------------//

IMPL_START(lea, 2) { *r1 = p2->addr; return 1; }

IMPL_START(mov, 2) { XSRCP(*r1, p2, sx); return 1; }
IMPL_START(movzx, 2) { XSRCP(*r1, p2, zx); return 1; }

IMPL_START(movb, 2) { SRCP(p2); *r1 = (ulong)(long)(char)p2->val; return 1; }
IMPL_START(movw, 2) { SRCP(p2); *r1 = (ulong)(long)(short)p2->val; return 1; }
IMPL_START(movd, 2) { SRCP(p2); *r1 = (ulong)(long)(int)p2->val; return 1; }

IMPL_START(nul, 1) { *r1 = 0; return 1; }
IMPL_START(nul, 2) { *r1 = 0; *r2 = 0; return 2; }

IMPL_START(xchg, 2)
{
    SRCP(p1);
    SRCP(p2);

    *r2 = p1->val;
    *r1 = p2->val;

    return 2;
}

//----------------------------------------------------------------------------//

IMPL_START(push, 1)
{
    XSRCP(p1->val, p1, zx);

    R(ESP) -= 8;
    writemem(p1->val, R(ESP), 8);

    return 0;
}

IMPL_START(push, 2)
{
    XSRCP(p1->val, p1, zx);
    XSRCP(p2->val, p2, zx);

    R(ESP) -= 16;
    writemem(p1->val, R(ESP) + 8, 8);
    writemem(p2->val, R(ESP) + 0, 8);

    return 0;
}

IMPL_START(push, 3)
{
    XSRCP(p1->val, p1, zx);
    XSRCP(p2->val, p2, zx);
    XSRCP(p3->val, p3, zx);

    R(ESP) -= 24;
    writemem(p1->val, R(ESP) + 16, 8);
    writemem(p2->val, R(ESP) + 8, 8);
    writemem(p3->val, R(ESP) + 0, 8);

    return 0;
}

//----------------------------------------------------------------------------//

IMPL_START(pop, 0)
{
    R(ESP) += 8;
    return 0;
}

IMPL_START(pop, 1)
{
    *r1 = readmemzx(R(ESP), 8);
    R(ESP) += 8;
    
    return 1;
}

IMPL_START(pop, 2)
{
    *r1 = readmemzx(R(ESP) + 0, 8);
    *r2 = readmemzx(R(ESP) + 8, 8);
    R(ESP) += 16;
    
    return 2;
}

//----------------------------------------------------------------------------//

IMPL_START(call, 1)
{
    SRCP(p1);

    R(ESP) -= 8;
    writemem(R(EIP), R(ESP), 8);
    R(EIP) = p1->val;

    return 0;
}

IMPL_START(call, 2)
{
    SRCP(p1);
    SRCP(p2);

    R(ESP) -= 8;
    writemem(R(EIP), R(ESP), 8);

    R(EIP) = p1->val;
    R(AX0) = p2->val;

    return 0;
}

IMPL_START(call, 3)
{
    SRCP(p1);
    SRCP(p2);
    SRCP(p3);

    R(ESP) -= 8;
    writemem(R(EIP), R(ESP), 8);

    R(EIP) = p1->val;
    R(AX0) = p2->val;
    R(AX1) = p3->val;

    return 0;
}

//----------------------------------------------------------------------------//

IMPL_START(ret, 0)
{
    R(EIP) = readmemzx(R(ESP), 8);
    R(ESP) += 8;

    return 0;
}

IMPL_START(ret, 1)
{
    R(EIP) = readmemzx(R(ESP), 8);
    R(ESP) += 8 + (p1->val * 8);

    return 0;
}

//----------------------------------------------------------------------------//

IMPL_START(enter, 0)
{
    R(ESP) -= 8;
    writemem(R(EBP), R(ESP), 8);
    R(EBP) = R(ESP);

    return 0;
}

IMPL_START(enter, 1)
{
    writemem(R(EBP), R(ESP) - 8, 8);
    R(EBP) = R(ESP) - 8;
    R(ESP) -= (p1->val + 1) * 8;

    return 0;
}

IMPL_START(enter, 2)
{
    ulong i, tmp;

    R(ESP) -= 8;
    tmp = R(ESP);
    writemem(R(EBP), R(ESP), 8);

    for (i = 0; i < p2->val; i++)
    {
        R(EBP) -= 8;
        R(ESP) -= 8;
        writemem(R(EBP), R(ESP), 8);
    }

    R(EBP) = tmp;
    R(ESP) = tmp - (p1->val * 8);

    return 0;
}

IMPL_START(leave, 0)
{
    R(ESP) = R(EBP) + 8;
    R(EBP) = readmemzx(R(EBP), 8);

    return 0;
}

//----------------------------------------------------------------------------//