Re: [Qemu-devel] [PATCH v2] target-mips: generate fences

[Richard Henderson]

On 09/08/2016 03:01 AM, Leon Alrae wrote:
> Make use of memory barrier TCG opcode in MIPS front end.
> 
> Signed-off-by: Leon Alrae <address@hidden>
> ---
> v2:
> * generate weaker barriers according to stype
> ---
>  target-mips/translate.c | 32 ++++++++++++++++++++++++++++++--
>  1 file changed, 30 insertions(+), 2 deletions(-)

Ah, even better.

Reviewed-by: Richard Henderson <address@hidden>

> +static void gen_sync(int stype)
> +{
> +    TCGOrder tcg_mo = TCG_BAR_SC;
> +
> +    switch (stype) {
> +    case 0x4: /* SYNC_WMB */
> +        tcg_mo |= TCG_MO_ST_ST;
> +        break;
> +    case 0x10: /* SYNC_MB */
> +        tcg_mo |= TCG_MO_ALL;
> +        break;
> +    case 0x11: /* SYNC_ACQUIRE */
> +        tcg_mo |= TCG_MO_LD_LD | TCG_MO_LD_ST;
> +        break;
> +    case 0x12: /* SYNC_RELEASE */
> +        tcg_mo |= TCG_MO_ST_ST | TCG_MO_LD_ST;
> +        break;
> +    case 0x13: /* SYNC_RMB */
> +        tcg_mo |= TCG_MO_LD_LD;
> +        break;
> +    default:
> +        tcg_mo |= TCG_MO_ALL;
> +        break;
> +    }

See git://github.com/rth7680/qemu.git tcg-next wherein this suggests that some
enhancement is desired in tcg/mips/ as well.  Not that I have a mips32r6 board
with which to test.  Would you or James Hogan be able to improve that?


r~