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Diffstat (limited to 'sysdeps/x86_64/multiarch/strcmp-avx2.S')
-rw-r--r--sysdeps/x86_64/multiarch/strcmp-avx2.S10
1 files changed, 10 insertions, 0 deletions
diff --git a/sysdeps/x86_64/multiarch/strcmp-avx2.S b/sysdeps/x86_64/multiarch/strcmp-avx2.S
index c9f246415f..360370cb7a 100644
--- a/sysdeps/x86_64/multiarch/strcmp-avx2.S
+++ b/sysdeps/x86_64/multiarch/strcmp-avx2.S
@@ -83,6 +83,16 @@ ENTRY (STRCMP)
 	je	L(char0)
 	jb	L(zero)
 #  ifdef USE_AS_WCSCMP
+#  ifndef __ILP32__
+	movq	%rdx, %rcx
+	/* Check if length could overflow when multiplied by
+	   sizeof(wchar_t). Checking top 8 bits will cover all potential
+	   overflow cases as well as redirect cases where its impossible to
+	   length to bound a valid memory region. In these cases just use
+	   'wcscmp'.  */
+	shrq	$56, %rcx
+	jnz	__wcscmp_avx2
+#  endif
 	/* Convert units: from wide to byte char.  */
 	shl	$2, %RDX_LP
 #  endif