From 9403b71ae97e3f1a91c796ddcbb4e6f044434734 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Fri, 13 May 2022 09:33:30 -0300 Subject: x86_64: Remove bzero optimization Both symbols are marked as legacy in POSIX.1-2001 and removed on POSIX.1-2008, although the prototypes are defined for _GNU_SOURCE or _DEFAULT_SOURCE. GCC also replaces bcopy with a memmove and bzero with memset on default configuration (to actually get a bzero libc call the code requires to omit string.h inclusion and built with -fno-builtin), so it is highly unlikely programs are actually calling libc bzero symbol. On a recent Linux distro (Ubuntu 22.04), there is no bzero calls by the installed binaries. $ cat count_bstring.sh #!/bin/bash files=`IFS=':';for i in $PATH; do test -d "$i" && find "$i" -maxdepth 1 -executable -type f; done` total=0 for file in $files; do symbols=`objdump -R $file 2>&1` if [ $? -eq 0 ]; then ncalls=`echo $symbols | grep -w $1 | wc -l` ((total=total+ncalls)) if [ $ncalls -gt 0 ]; then echo "$file: $ncalls" fi fi done echo "TOTAL=$total" $ ./count_bstring.sh bzero TOTAL=0 Checked on x86_64-linux-gnu. --- sysdeps/x86_64/multiarch/memset-evex-unaligned-erms.S | 3 --- 1 file changed, 3 deletions(-) (limited to 'sysdeps/x86_64/multiarch/memset-evex-unaligned-erms.S') diff --git a/sysdeps/x86_64/multiarch/memset-evex-unaligned-erms.S b/sysdeps/x86_64/multiarch/memset-evex-unaligned-erms.S index 5d8fa78f05..6370021506 100644 --- a/sysdeps/x86_64/multiarch/memset-evex-unaligned-erms.S +++ b/sysdeps/x86_64/multiarch/memset-evex-unaligned-erms.S @@ -19,9 +19,6 @@ vpbroadcastb d, %VEC0; \ movq r, %rax -# define BZERO_ZERO_VEC0() \ - vpxorq %XMM0, %XMM0, %XMM0 - # define WMEMSET_SET_VEC0_AND_SET_RETURN(d, r) \ vpbroadcastd d, %VEC0; \ movq r, %rax -- cgit 1.4.1