From a1de30c6ae99af046735670b421f9709c6315b62 Mon Sep 17 00:00:00 2001
From: Packit Service <user-cont-team+packit-service@redhat.com>
Date: Mar 14 2021 14:58:02 +0000
Subject: Apply patch glibc-rh1871394-1.patch


patch_name: glibc-rh1871394-1.patch
present_in_specfile: true
location_in_specfile: 359

---

diff --git a/sysdeps/x86_64/multiarch/strcmp-avx2.S b/sysdeps/x86_64/multiarch/strcmp-avx2.S
index e8397f3..327e3d8 100644
--- a/sysdeps/x86_64/multiarch/strcmp-avx2.S
+++ b/sysdeps/x86_64/multiarch/strcmp-avx2.S
@@ -591,7 +591,14 @@ L(loop_cross_page_2_vec):
 	movl	$(PAGE_SIZE / (VEC_SIZE * 4) - 1), %esi
 
 	testq	%rdi, %rdi
+# ifdef USE_AS_STRNCMP
+	/* At this point, if %rdi value is 0, it already tested
+	   VEC_SIZE*4+%r10 byte starting from %rax. This label
+	   checks whether strncmp maximum offset reached or not.  */
+	je	L(string_nbyte_offset_check)
+# else
 	je	L(back_to_loop)
+# endif
 	tzcntq	%rdi, %rcx
 	addq	%r10, %rcx
 	/* Adjust for number of bytes skipped.  */
@@ -627,6 +634,14 @@ L(loop_cross_page_2_vec):
 	VZEROUPPER
 	ret
 
+# ifdef USE_AS_STRNCMP
+L(string_nbyte_offset_check):
+	leaq	(VEC_SIZE * 4)(%r10), %r10
+	cmpq	%r10, %r11
+	jbe	L(zero)
+	jmp	L(back_to_loop)
+# endif
+
 	.p2align 4
 L(cross_page_loop):
 	/* Check one byte/dword at a time.  */