[gcc r13-7642] Change fma_reassoc_width tuning for ampere1

[gcc r13-7642] Change fma_reassoc_width tuning for ampere1

[Di Zhao]

https://gcc.gnu.org/g:a147d1d551c55f715f401a826140d08caf5abe1e

commit r13-7642-ga147d1d551c55f715f401a826140d08caf5abe1e
Author: Di Zhao OS <dizhao@os.amperecomputing.com>
Date:   Thu Jun 22 15:16:57 2023 +0100

    Change fma_reassoc_width tuning for ampere1
    
    This patch enables reassociation of floating-point additions on ampere1.
    This brings about 1% overall benefit on spec2017 fprate cases. (There
    are minor regressions in 510.parest_r and 508.namd_r, analyzed here:
    https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110279 .)
    
    gcc/ChangeLog:
    
            * config/aarch64/aarch64.cc: Change fma_reassoc_width for ampere1.

Diff:
---
 gcc/config/aarch64/aarch64.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index f5db5379543..822a2b49a46 100644
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -1927,7 +1927,7 @@ static const struct tune_params ampere1_tunings =
   "32:16",	/* loop_align.  */
   2,	/* int_reassoc_width.  */
   4,	/* fp_reassoc_width.  */
-  1,	/* fma_reassoc_width.  */
+  4,	/* fma_reassoc_width.  */
   2,	/* vec_reassoc_width.  */
   2,	/* min_div_recip_mul_sf.  */
   2,	/* min_div_recip_mul_df.  */