[PATCH] x86-64: Use testl to check __x86_string_control

H.J. Lu hjl.tools@gmail.com
Sat Aug 28 13:15:30 GMT 2021


Use testl, instead of andl, to check __x86_string_control to avoid
updating __x86_string_control.
---
 sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S b/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S
index 9f02624375..abde8438d4 100644
--- a/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S
+++ b/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S
@@ -325,7 +325,7 @@ L(movsb):
 	/* Avoid slow backward REP MOVSB.  */
 	jb	L(more_8x_vec_backward)
 # if AVOID_SHORT_DISTANCE_REP_MOVSB
-	andl	$X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB, __x86_string_control(%rip)
+	testl	$X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB, __x86_string_control(%rip)
 	jz	3f
 	movq	%rdi, %rcx
 	subq	%rsi, %rcx
@@ -333,7 +333,7 @@ L(movsb):
 # endif
 1:
 # if AVOID_SHORT_DISTANCE_REP_MOVSB
-	andl	$X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB, __x86_string_control(%rip)
+	testl	$X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB, __x86_string_control(%rip)
 	jz	3f
 	movq	%rsi, %rcx
 	subq	%rdi, %rcx
-- 
2.31.1



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