Re: [PATCH v2 05/50] tcg: Expose tcg_gen_ussub_sat()

On 7/29/26 20:09, Anton Johansson via qemu development wrote:
> @@ -2399,14 +2399,14 @@ void tcg_gen_gvec_usadd(unsigned vece, uint32_t dofs, uint32_t aofs,
>       tcg_gen_gvec_3(dofs, aofs, bofs, oprsz, maxsz, &g[vece]);
>   }
>   
> -static void tcg_gen_ussub_i32(TCGv_i32 d, TCGv_i32 a, TCGv_i32 b)
> +void tcg_gen_ussub_i32(TCGv_i32 d, TCGv_i32 a, TCGv_i32 b)
>   {
>       TCGv_i32 min = tcg_constant_i32(0);
>       tcg_gen_sub_i32(d, a, b);
>       tcg_gen_movcond_i32(TCG_COND_LTU, d, a, b, min, d);
>   }
These aren't quite general purpose.  The existing formulation "knows" that d does not 
overlap a or b -- which is true under the limited invocation here.  If you want to expose 
these for wider use, you need to fix that by allocating a new temporary around this operation.


r~