From 032545ebd3ab2248b137bc92df0bd2864031cc8b Mon Sep 17 00:00:00 2001 From: Wilco Dijkstra Date: Fri, 13 Dec 2024 15:43:07 +0000 Subject: [PATCH] math: Improve layout of exp/exp10 data GCC aligns global data to 16 bytes if their size is >= 16 bytes. This patch changes the exp_data struct slightly so that the fields are better aligned and without gaps. As a result on targets that support them, more load-pair instructions are used in exp. The exp benchmark improves 2.5%, "144bits" by 7.2%, "768bits" by 12.7% on Neoverse V2. Reviewed-by: Adhemerval Zanella (cherry picked from commit 5afaf99edb326fd9f36eb306a828d129a3a1d7f7) (cherry picked from commit 5a08d049dc5037e89eb95bb1506652f0043fa39e) --- sysdeps/ieee754/dbl-64/math_config.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/sysdeps/ieee754/dbl-64/math_config.h b/sysdeps/ieee754/dbl-64/math_config.h index 3cbaeede64..01f0716aae 100644 --- a/sysdeps/ieee754/dbl-64/math_config.h +++ b/sysdeps/ieee754/dbl-64/math_config.h @@ -134,10 +134,11 @@ check_uflow (double x) extern const struct exp_data { double invln2N; - double shift; double negln2hiN; double negln2loN; double poly[4]; /* Last four coefficients. */ + double shift; + double exp2_shift; double exp2_poly[EXP2_POLY_ORDER]; uint64_t tab[2*(1 << EXP_TABLE_BITS)];