Commit 0ccb9c1d authored by Laurent Vivier's avatar Laurent Vivier
Browse files

target-m68k: add 680x0 divu/divs variants 



Update helper to set the throwing location in case of div-by-0.
Cleanup divX.w and add quad word variants of divX.l.

Signed-off-by: default avatarLaurent Vivier <laurent@vivier.eu>
Reviewed-by: default avatarRichard Henderson <rth@twidle.net>
[laurent: modified to clear Z on overflow, as found with risu]
parent 8be95def

linux-user/main.c

+7 −0
Original line number Diff line number Diff line
@@ -2864,6 +2864,13 @@ void cpu_loop(CPUM68KState *env) 
            info._sifields._sigfault._addr = env->pc;

            queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);

            break;

        case EXCP_DIV0:

            info.si_signo = TARGET_SIGFPE;

            info.si_errno = 0;

            info.si_code = TARGET_FPE_INTDIV;

            info._sifields._sigfault._addr = env->pc;

            queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);

            break;

        case EXCP_TRAP0:

            {

                abi_long ret;

target/m68k/cpu.h

+0 −4
Original line number Diff line number Diff line
@@ -95,10 +95,6 @@ typedef struct CPUM68KState { 
    uint32_t macsr;

    uint32_t mac_mask;



    /* Temporary storage for DIV helpers.  */

    uint32_t div1;

    uint32_t div2;



    /* MMU status.  */

    struct {

        uint32_t ar;

target/m68k/helper.h

+6 −2
Original line number Diff line number Diff line 
DEF_HELPER_1(bitrev, i32, i32)

DEF_HELPER_1(ff1, i32, i32)

DEF_HELPER_FLAGS_2(sats, TCG_CALL_NO_RWG_SE, i32, i32, i32)

DEF_HELPER_2(divu, void, env, i32)

DEF_HELPER_2(divs, void, env, i32)

DEF_HELPER_3(divuw, void, env, int, i32)

DEF_HELPER_3(divsw, void, env, int, s32)

DEF_HELPER_4(divul, void, env, int, int, i32)

DEF_HELPER_4(divsl, void, env, int, int, s32)

DEF_HELPER_4(divull, void, env, int, int, i32)

DEF_HELPER_4(divsll, void, env, int, int, s32)

DEF_HELPER_3(shl_cc, i32, env, i32, i32)

DEF_HELPER_3(shr_cc, i32, env, i32, i32)

DEF_HELPER_3(sar_cc, i32, env, i32, i32)

target/m68k/op_helper.c

+158 −25
Original line number Diff line number Diff line
@@ -166,12 +166,17 @@ bool m68k_cpu_exec_interrupt(CPUState *cs, int interrupt_request) 
    return false;

}



static void raise_exception(CPUM68KState *env, int tt)

static void raise_exception_ra(CPUM68KState *env, int tt, uintptr_t raddr)

{

    CPUState *cs = CPU(m68k_env_get_cpu(env));



    cs->exception_index = tt;

    cpu_loop_exit(cs);

    cpu_loop_exit_restore(cs, raddr);

}



static void raise_exception(CPUM68KState *env, int tt)

{

    raise_exception_ra(env, tt, 0);

}



void HELPER(raise_exception)(CPUM68KState *env, uint32_t tt)
@@ -179,51 +184,179 @@ void HELPER(raise_exception)(CPUM68KState *env, uint32_t tt) 
    raise_exception(env, tt);

}



void HELPER(divu)(CPUM68KState *env, uint32_t word)

void HELPER(divuw)(CPUM68KState *env, int destr, uint32_t den)

{

    uint32_t num;

    uint32_t den;

    uint32_t quot;

    uint32_t rem;

    uint32_t num = env->dregs[destr];

    uint32_t quot, rem;



    if (den == 0) {

        raise_exception_ra(env, EXCP_DIV0, GETPC());

    }

    quot = num / den;

    rem = num % den;



    env->cc_c = 0; /* always cleared, even if overflow */

    if (quot > 0xffff) {

        env->cc_v = -1;

        /* real 68040 keeps N and unset Z on overflow,

         * whereas documentation says "undefined"

         */

        env->cc_z = 1;

        return;

    }

    env->dregs[destr] = deposit32(quot, 16, 16, rem);

    env->cc_z = (int16_t)quot;

    env->cc_n = (int16_t)quot;

    env->cc_v = 0;

}



void HELPER(divsw)(CPUM68KState *env, int destr, int32_t den)

{

    int32_t num = env->dregs[destr];

    uint32_t quot, rem;



    num = env->div1;

    den = env->div2;

    /* ??? This needs to make sure the throwing location is accurate.  */

    if (den == 0) {

        raise_exception(env, EXCP_DIV0);

        raise_exception_ra(env, EXCP_DIV0, GETPC());

    }

    quot = num / den;

    rem = num % den;



    env->cc_v = (word && quot > 0xffff ? -1 : 0);

    env->cc_c = 0; /* always cleared, even if overflow */

    if (quot != (int16_t)quot) {

        env->cc_v = -1;

        /* nothing else is modified */

        /* real 68040 keeps N and unset Z on overflow,

         * whereas documentation says "undefined"

         */

        env->cc_z = 1;

        return;

    }

    env->dregs[destr] = deposit32(quot, 16, 16, rem);

    env->cc_z = (int16_t)quot;

    env->cc_n = (int16_t)quot;

    env->cc_v = 0;

}



void HELPER(divul)(CPUM68KState *env, int numr, int regr, uint32_t den)

{

    uint32_t num = env->dregs[numr];

    uint32_t quot, rem;



    if (den == 0) {

        raise_exception_ra(env, EXCP_DIV0, GETPC());

    }

    quot = num / den;

    rem = num % den;



    env->cc_c = 0;

    env->cc_z = quot;

    env->cc_n = quot;

    env->cc_v = 0;



    if (m68k_feature(env, M68K_FEATURE_CF_ISA_A)) {

        if (numr == regr) {

            env->dregs[numr] = quot;

        } else {

            env->dregs[regr] = rem;

        }

    } else {

        env->dregs[regr] = rem;

        env->dregs[numr] = quot;

    }

}



void HELPER(divsl)(CPUM68KState *env, int numr, int regr, int32_t den)

{

    int32_t num = env->dregs[numr];

    int32_t quot, rem;



    if (den == 0) {

        raise_exception_ra(env, EXCP_DIV0, GETPC());

    }

    quot = num / den;

    rem = num % den;



    env->cc_c = 0;

    env->cc_z = quot;

    env->cc_n = quot;

    env->cc_v = 0;



    env->div1 = quot;

    env->div2 = rem;

    if (m68k_feature(env, M68K_FEATURE_CF_ISA_A)) {

        if (numr == regr) {

            env->dregs[numr] = quot;

        } else {

            env->dregs[regr] = rem;

        }

    } else {

        env->dregs[regr] = rem;

        env->dregs[numr] = quot;

    }

}



void HELPER(divs)(CPUM68KState *env, uint32_t word)

void HELPER(divull)(CPUM68KState *env, int numr, int regr, uint32_t den)

{

    int32_t num;

    int32_t den;

    int32_t quot;

    uint64_t num = deposit64(env->dregs[numr], 32, 32, env->dregs[regr]);

    uint64_t quot;

    uint32_t rem;



    if (den == 0) {

        raise_exception_ra(env, EXCP_DIV0, GETPC());

    }

    quot = num / den;

    rem = num % den;



    env->cc_c = 0; /* always cleared, even if overflow */

    if (quot > 0xffffffffULL) {

        env->cc_v = -1;

        /* real 68040 keeps N and unset Z on overflow,

         * whereas documentation says "undefined"

         */

        env->cc_z = 1;

        return;

    }

    env->cc_z = quot;

    env->cc_n = quot;

    env->cc_v = 0;



    /*

     * If Dq and Dr are the same, the quotient is returned.

     * therefore we set Dq last.

     */



    env->dregs[regr] = rem;

    env->dregs[numr] = quot;

}



void HELPER(divsll)(CPUM68KState *env, int numr, int regr, int32_t den)

{

    int64_t num = deposit64(env->dregs[numr], 32, 32, env->dregs[regr]);

    int64_t quot;

    int32_t rem;



    num = env->div1;

    den = env->div2;

    if (den == 0) {

        raise_exception(env, EXCP_DIV0);

        raise_exception_ra(env, EXCP_DIV0, GETPC());

    }

    quot = num / den;

    rem = num % den;



    env->cc_v = (word && quot != (int16_t)quot ? -1 : 0);

    env->cc_c = 0; /* always cleared, even if overflow */

    if (quot != (int32_t)quot) {

        env->cc_v = -1;

        /* real 68040 keeps N and unset Z on overflow,

         * whereas documentation says "undefined"

         */

        env->cc_z = 1;

        return;

    }

    env->cc_z = quot;

    env->cc_n = quot;

    env->cc_c = 0;

    env->cc_v = 0;



    /*

     * If Dq and Dr are the same, the quotient is returned.

     * therefore we set Dq last.

     */



    env->div1 = quot;

    env->div2 = rem;

    env->dregs[regr] = rem;

    env->dregs[numr] = quot;

}

target/m68k/qregs.def

+0 −2
Original line number Diff line number Diff line
@@ -7,7 +7,5 @@ DEFO32(CC_C, cc_c) 
DEFO32(CC_N, cc_n)

DEFO32(CC_V, cc_v)

DEFO32(CC_Z, cc_z)

DEFO32(DIV1, div1)

DEFO32(DIV2, div2)

DEFO32(MACSR, macsr)

DEFO32(MAC_MASK, mac_mask)