kvisc/pc/instrs/stack.c

// 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 "instrs.h"
#include "arch_i.h"

//
// Stack manipulation instructions
//

IMPL_START_1(push)
{
    CHK_STACK(<);
    PUSH(v1);
}
IMPL_END;

IMPL_START_1(pop)
{
    CHK_STACK(<=);
    POP(v1);
}
IMPL_OUT;

IMPL_START_1(call)
{
    CHK_STACK(<);
    PUSH(ctx->r[RIP].val);
    JUMP(v1);
}
IMPL_END;

IMPL_START_0(ret)
{
    CHK_STACK(<=);
    POP(ctx->r[RIP].val);
}
IMPL_END;

IMPL_START_0(enter)
{
    // We don't CHK_STACK(<) here because ENTER
    // (should) always be preceded by a CALL,
    // which already checks the stack
    PUSH(ctx->r[RBP].val);
    ctx->r[RBP].val = ctx->r[RSP].val;
}
IMPL_END;

IMPL_START_0(leave)
{
    // Do NOT check stack here
    // (it would always fail)
    POP(ctx->r[RBP].val);
}
IMPL_END;

IMPL_START_0(pushf)
{
    CHK_STACK(<);

    writemem64(ctx, ctx->r[FLG].val, ctx->r[RSP].val);
    ctx->r[RSP].val -= 8;
}
IMPL_END;

IMPL_START_0(popf)
{
    CHK_STACK(<=);

    // XXX
    CHK_SUPERV();

    ctx->r[RSP].val += 8;
    ctx->r[FLG].val = readmem64(ctx, ctx->r[RSP].val);
}
IMPL_END;