[PATCH v2] rs6000: Disable HTM for Power10 and later

[Segher Boessenkool]

Hi!

On Mon, Nov 30, 2020 at 06:36:30PM +0800, Kewen.Lin wrote:
> --- a/gcc/config/rs6000/rs6000-cpus.def
> +++ b/gcc/config/rs6000/rs6000-cpus.def
> @@ -51,7 +51,6 @@
>  				 | OPTION_MASK_CRYPTO			\
>  				 | OPTION_MASK_DIRECT_MOVE		\
>  				 | OPTION_MASK_EFFICIENT_UNALIGNED_VSX	\
> -				 | OPTION_MASK_HTM			\
>  				 | OPTION_MASK_QUAD_MEMORY		\
>  				 | OPTION_MASK_QUAD_MEMORY_ATOMIC)

(this is in #define ISA_2_7_MASKS_SERVER)

That looks fine.

> -RS6000_CPU ("power8", PROCESSOR_POWER8, MASK_POWERPC64 | ISA_2_7_MASKS_SERVER)
> -RS6000_CPU ("power9", PROCESSOR_POWER9, MASK_POWERPC64 | ISA_3_0_MASKS_SERVER)
> +RS6000_CPU ("power8", PROCESSOR_POWER8, MASK_POWERPC64 | ISA_2_7_MASKS_SERVER
> +	    | OPTION_MASK_HTM)
> +RS6000_CPU ("power9", PROCESSOR_POWER9, MASK_POWERPC64 | ISA_3_0_MASKS_SERVER
> +	    | OPTION_MASK_HTM)

> -RS6000_CPU ("powerpc64le", PROCESSOR_POWER8, MASK_POWERPC64 | ISA_2_7_MASKS_SERVER)
> +RS6000_CPU ("powerpc64le", PROCESSOR_POWER8, MASK_POWERPC64 | ISA_2_7_MASKS_SERVER
> +	    | OPTION_MASK_HTM)

This, too.

> --- a/gcc/config/rs6000/rs6000.c
> +++ b/gcc/config/rs6000/rs6000.c
> @@ -3807,7 +3807,8 @@ rs6000_option_override_internal (bool global_init_p)
>    /* If little-endian, default to -mstrict-align on older processors.
>       Testing for htm matches power8 and later.  */
>    if (!BYTES_BIG_ENDIAN
> -      && !(processor_target_table[tune_index].target_enable & OPTION_MASK_HTM))
> +      && !(processor_target_table[tune_index].target_enable
> +	   & OPTION_MASK_CRYPTO))
>      rs6000_isa_flags |= ~rs6000_isa_flags_explicit & OPTION_MASK_STRICT_ALIGN;

But not this.  Not all ISA 2.07 processors implement the crypto
category.  You could use OPTION_MASK_DIRECT_MOVE, instead?

Okay for trunk with that change (if that works ;-) )  Thanks!


Segher