Commit f69c24e4 authored by Bastian Koppelmann's avatar Bastian Koppelmann
Browse files

target-tricore: properly fix dvinit_b/h_13 



The TriCore documentation was wrong on how to calculate ovf bits for those two
instructions, which I confirmed with real hardware (TC1796 chip). An ovf
actually happens, if the result (without remainder) does not fit into 8/16 bits.

Signed-off-by: default avatarBastian Koppelmann <kbastian@mail.uni-paderborn.de>
parent 00e1754f

target-tricore/op_helper.c

+10 −30
Original line number Diff line number Diff line
@@ -1942,29 +1942,19 @@ uint64_t helper_unpack(target_ulong arg1) 
uint64_t helper_dvinit_b_13(CPUTriCoreState *env, uint32_t r1, uint32_t r2)

{

    uint64_t ret;

    int32_t abs_sig_dividend, abs_base_dividend, abs_divisor;

    int32_t quotient_sign;

    int32_t abs_sig_dividend, abs_divisor;



    ret = sextract32(r1, 0, 32);

    ret = ret << 24;

    quotient_sign = 0;

    if (!((r1 & 0x80000000) == (r2 & 0x80000000))) {

        ret |= 0xffffff;

        quotient_sign = 1;

    }



    abs_sig_dividend = abs((int32_t)r1) >> 7;

    abs_base_dividend = abs((int32_t)r1) & 0x7f;

    abs_sig_dividend = abs((int32_t)r1) >> 8;

    abs_divisor = abs((int32_t)r2);

    /* calc overflow */

    env->PSW_USB_V = 0;

    if ((quotient_sign) && (abs_divisor)) {

        env->PSW_USB_V = (((abs_sig_dividend == abs_divisor) &&

                         (abs_base_dividend >= abs_divisor)) ||

                         (abs_sig_dividend > abs_divisor));

    } else {

        env->PSW_USB_V = (abs_sig_dividend >= abs_divisor);

    }

    /* calc overflow

       ofv if (a/b >= 255) <=> (a/255 >= b) */

    env->PSW_USB_V = (abs_sig_dividend >= abs_divisor) << 31;

    env->PSW_USB_V = env->PSW_USB_V << 31;

    env->PSW_USB_SV |= env->PSW_USB_V;

    env->PSW_USB_AV = 0;
@@ -1992,29 +1982,19 @@ uint64_t helper_dvinit_b_131(CPUTriCoreState *env, uint32_t r1, uint32_t r2) 
uint64_t helper_dvinit_h_13(CPUTriCoreState *env, uint32_t r1, uint32_t r2)

{

    uint64_t ret;

    int32_t abs_sig_dividend, abs_base_dividend, abs_divisor;

    int32_t quotient_sign;

    int32_t abs_sig_dividend, abs_divisor;



    ret = sextract32(r1, 0, 32);

    ret = ret << 16;

    quotient_sign = 0;

    if (!((r1 & 0x80000000) == (r2 & 0x80000000))) {

        ret |= 0xffff;

        quotient_sign = 1;

    }



    abs_sig_dividend = abs((int32_t)r1) >> 7;

    abs_base_dividend = abs((int32_t)r1) & 0x7f;

    abs_sig_dividend = abs((int32_t)r1) >> 16;

    abs_divisor = abs((int32_t)r2);

    /* calc overflow */

    env->PSW_USB_V = 0;

    if ((quotient_sign) && (abs_divisor)) {

        env->PSW_USB_V = (((abs_sig_dividend == abs_divisor) &&

                         (abs_base_dividend >= abs_divisor)) ||

                         (abs_sig_dividend > abs_divisor));

    } else {

        env->PSW_USB_V = (abs_sig_dividend >= abs_divisor);

    }

    /* calc overflow

       ofv if (a/b >= 0xffff) <=> (a/0xffff >= b) */

    env->PSW_USB_V = (abs_sig_dividend >= abs_divisor) << 31;

    env->PSW_USB_V = env->PSW_USB_V << 31;

    env->PSW_USB_SV |= env->PSW_USB_V;

    env->PSW_USB_AV = 0;