> -----Original Message-----
> From: Richard Biener <[email protected]>
> Sent: Thursday, October 30, 2025 8:39 PM
> To: [email protected]
> Cc: Liu, Hongtao <[email protected]>; [email protected]
> Subject: [PATCH] [i386] Fix type in ix86_move_max setup
>
> There's a typo in the way we compute opts->x_ix86_move_max:
>
> if (opts_set->x_ix86_move_max == PVW_NONE)
> {
> /* Set the maximum number of bits can be moved from memory to
> memory efficiently. */
> if (opts_set->x_prefer_vector_width_type != PVW_NONE)
> opts->x_ix86_move_max = opts->x_prefer_vector_width_type;
> else if (ix86_tune_features[X86_TUNE_AVX512_MOVE_BY_PIECES])
> opts->x_ix86_move_max = PVW_AVX512;
> else if (ix86_tune_features[X86_TUNE_AVX256_MOVE_BY_PIECES])
> opts->x_ix86_move_max = PVW_AVX256;
> else
> {
> opts->x_ix86_move_max = opts->x_prefer_vector_width_type;
> /* */ if (opts_set->x_ix86_move_max == PVW_NONE)
> {
> if (TARGET_AVX512F_P (opts->x_ix86_isa_flags))
> opts->x_ix86_move_max = PVW_AVX512;
> /* Align with vectorizer to avoid potential STLF issue. */
> else if (TARGET_AVX_P (opts->x_ix86_isa_flags))
> opts->x_ix86_move_max = PVW_AVX256;
> else
> opts->x_ix86_move_max = PVW_AVX128;
> }
> }
> }
>
> as written the /* */ condition is redundant with the outermost one.
> But intended is (IMO) that the earlier set opts->x_prefer_vector_width_type
> via X86_TUNE_{AVX128,AVX256}_OPTIMAL takes precedence over the ISA
> based setup that follows. So instead of checking opts_set we want to check
> whether the previous assignment left us with still PVW_NONE.
> The issue makes us ignore
> X86_TUNE_AVX128_OPTIMAL/X86_TUNE_AVX256_OPTIMAL
> when determining opts->x_ix86_move_max.
>
> Bootstrap and regtest ongoing on x86_64-unknown-linux-gnu. The issue
> seems to be present on branches as well.
>
> OK for trunk (and branches)?
Ok, thanks.
>
> Thanks,
> Richard.
>
> * config/i386/i386-options.cc (ix86_option_override_internal):
> Fix check during opts->x_ix86_move_max initialization.
> ---
> gcc/config/i386/i386-options.cc | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/gcc/config/i386/i386-options.cc b/gcc/config/i386/i386-options.cc
> index dadcf7664c6..ba598a817f3 100644
> --- a/gcc/config/i386/i386-options.cc
> +++ b/gcc/config/i386/i386-options.cc
> @@ -2917,7 +2917,7 @@ ix86_option_override_internal (bool main_args_p,
> else
> {
> opts->x_ix86_move_max = opts->x_prefer_vector_width_type;
> - if (opts_set->x_ix86_move_max == PVW_NONE)
> + if (opts->x_ix86_move_max == PVW_NONE)
> {
> if (TARGET_AVX512F_P (opts->x_ix86_isa_flags))
> opts->x_ix86_move_max = PVW_AVX512;
> --
> 2.51.0
