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authorNoah Goldstein <goldstein.w.n@gmail.com>2022-10-19 19:13:38 -0700
committerNoah Goldstein <goldstein.w.n@gmail.com>2022-10-20 11:29:05 -0700
commit8775479804cfea2bbe4dcdf19d6589264c96d5fb (patch)
tree30638b90a3c7ba416a9f5cc868eaf8040b5037fc
parentf04f8373ddd71794050b904174fb06967be6393f (diff)
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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.
-rw-r--r--sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S4
1 files changed, 4 insertions, 0 deletions
diff --git a/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S b/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S
index 5b758cae5e..f6d7f3e88b 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