From: Noah Goldstein Date: Thu, 20 Oct 2022 02:13:38 +0000 (-0700) Subject: x86: Use `testb` for FSRM check in memmove-vec-unaligned-erms X-Git-Tag: glibc-2.37~232 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=8775479804cfea2bbe4dcdf19d6589264c96d5fb;p=thirdparty%2Fglibc.git x86: Use `testb` for FSRM check in memmove-vec-unaligned-erms `testb` saves a bit of code size is the imm-operand can be encoded 1-bytes. Tested on x86-64. --- diff --git a/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S b/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S index 5b758cae5e6..f6d7f3e88b9 100644 --- a/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S +++ b/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S @@ -616,7 +616,11 @@ L(movsb): jae L(large_memcpy_2x_check) # if AVOID_SHORT_DISTANCE_REP_MOVSB || ALIGN_MOVSB /* Only avoid short movsb if CPU has FSRM. */ +# if X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB < 256 + testb $X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB, __x86_string_control(%rip) +# else testl $X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB, __x86_string_control(%rip) +# endif jz L(skip_short_movsb_check) # if AVOID_SHORT_DISTANCE_REP_MOVSB /* Avoid "rep movsb" if RCX, the distance between source and