[gcc r16-4733] [i386] Fix type in ix86_move_max setup

[Richard Biener via Gcc-cvs]

https://gcc.gnu.org/g:3474482bb57604f6581f6e7dc5b2917495d42502

commit r16-4733-g3474482bb57604f6581f6e7dc5b2917495d42502
Author: Richard Biener <rguent...@suse.de>
Date:   Thu Oct 30 13:30:21 2025 +0100

    [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.
    
            * config/i386/i386-options.cc (ix86_option_override_internal):
            Fix check during opts->x_ix86_move_max initialization.

Diff:
---
 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 dadcf7664c63..ba598a817f30 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;