On 17 June 2018 at 16:53, John Arbuckle <programmingk...@gmail.com> wrote:
> Fix the helper_fpscr_clrbit() function so it correctly
> sets the FEX and VX bits.
>
> Signed-off-by: John Arbuckle <programmingk...@gmail.com>
> ---
> target/ppc/fpu_helper.c | 57
> +++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 57 insertions(+)
>
> diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c
> index d31a933cbb..7e697a11d0 100644
> --- a/target/ppc/fpu_helper.c
> +++ b/target/ppc/fpu_helper.c
> @@ -325,6 +325,63 @@ void helper_fpscr_clrbit(CPUPPCState *env, uint32_t bit)
> case FPSCR_RN:
> fpscr_set_rounding_mode(env);
> break;
> + case FPSCR_VXSNAN:
> + case FPSCR_VXISI:
> + case FPSCR_VXIDI:
> + case FPSCR_VXZDZ:
> + case FPSCR_VXIMZ:
> + case FPSCR_VXVC:
> + case FPSCR_VXSOFT:
> + case FPSCR_VXSQRT:
> + case FPSCR_VXCVI:
> + {
> + int vxsnan, vxisi, vxidi, vxzdz, vximz, vxvc, vxsoft, vxsqrt,
> vxcvi;
> + vxsnan = (env->fpscr >> (31 - FPSCR_VXSNAN)) & 1;
> + vxisi = (env->fpscr >> (31 - FPSCR_VXISI)) & 1;
> + vxidi = (env->fpscr >> (31 - FPSCR_VXIDI)) & 1;
> + vxzdz = (env->fpscr >> (31 - FPSCR_VXZDZ)) & 1;
> + vximz = (env->fpscr >> (31 - FPSCR_VXIMZ)) & 1;
> + vxvc = (env->fpscr >> (31 - FPSCR_VXVC)) & 1;
> + vxsoft = (env->fpscr >> (31 - FPSCR_VXSOFT)) & 1;
> + vxsqrt = (env->fpscr >> (31 - FPSCR_VXSQRT)) & 1;
> + vxcvi = (env->fpscr >> (31 - FPSCR_VXCVI)) & 1;
> + if (~(vxsnan & vxisi & vxidi & vxzdz & vximz & vxvc & vxsoft &
> + vxsqrt & vxcvi)) {
If all you're doing is checking "are none of these bits set"
then you don't need to laboriously extract every bit and then
AND them together -- you can just use
if (!(env->fpscr & some_mask))
In fact the headers already define a macro which does that mask
on env->fpscr, so this can just be
if (!fpscr_ix) {
env->fpscr &= ~(1 << FPSCR_VX);
}
> + /* Set VX bit to zero */
> + env->fpscr = env->fpscr & ~(1 << FPSCR_VX);
> + }
> + }
> + break;
> + case FPSCR_VX:
> + case FPSCR_OX:
> + case FPSCR_UX:
> + case FPSCR_ZX:
> + case FPSCR_XX:
> + case FPSCR_VE:
> + case FPSCR_OE:
> + case FPSCR_UE:
> + case FPSCR_ZE:
> + case FPSCR_XE:
> + {
> + int vx, ox, ux, zx, xx, ve, oe, ue, ze, xe;
> + vx = (env->fpscr >> (31 - FPSCR_VX)) & 1;
> + ox = (env->fpscr >> (31 - FPSCR_OX)) & 1;
> + ux = (env->fpscr >> (31 - FPSCR_UX)) & 1;
> + zx = (env->fpscr >> (31 - FPSCR_ZX)) & 1;
> + xx = (env->fpscr >> (31 - FPSCR_XX)) & 1;
> + ve = (env->fpscr >> (31 - FPSCR_VE)) & 1;
> + oe = (env->fpscr >> (31 - FPSCR_OE)) & 1;
> + ue = (env->fpscr >> (31 - FPSCR_UE)) & 1;
> + ze = (env->fpscr >> (31 - FPSCR_ZE)) & 1;
> + xe = (env->fpscr >> (31 - FPSCR_XE)) & 1;
> + bool fex;
> + fex = (vx & ve) | (ox & oe) | (ux & ue) | (zx & ze) | (xx & xe);
> + unsigned int mask;
> + mask = (1 << FPSCR_FEX);
> + /* Set the FEX bit */
> + env->fpscr = (env->fpscr & ~mask) | (-fex & mask);
Similarly I think this is
if (!fpscr_eex) {
env->fpscr &= ~(1 << FPSCR_FEX);
}
> + }
> + break;
> default:
> break;
> }
> --
> 2.14.3 (Apple Git-98)
>
thanks
-- PMM
