--- zzzz-none-000/linux-3.10.107/arch/arc/lib/memcmp.S	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/arc/lib/memcmp.S	2021-02-04 17:41:59.000000000 +0000
@@ -6,7 +6,7 @@
  * published by the Free Software Foundation.
  */
 
-#include <asm/linkage.h>
+#include <linux/linkage.h>
 
 #ifdef __LITTLE_ENDIAN__
 #define WORD2 r2
@@ -16,7 +16,7 @@
 #define SHIFT r2
 #endif
 
-ARC_ENTRY memcmp
+ENTRY(memcmp)
 	or	r12,r0,r1
 	asl_s	r12,r12,30
 	sub	r3,r2,1
@@ -24,14 +24,32 @@
 	ld	r4,[r0,0]
 	ld	r5,[r1,0]
 	lsr.f	lp_count,r3,3
+#ifdef CONFIG_ISA_ARCV2
+	/* In ARCv2 a branch can't be the last instruction in a zero overhead
+	 * loop.
+	 * So we move the branch to the start of the loop, duplicate it
+	 * after the end, and set up r12 so that the branch isn't taken
+	 *  initially.
+	 */
+	mov_s	r12,WORD2
+	lpne	.Loop_end
+	brne	WORD2,r12,.Lodd
+	ld	WORD2,[r0,4]
+#else
 	lpne	.Loop_end
 	ld_s	WORD2,[r0,4]
+#endif
 	ld_s	r12,[r1,4]
 	brne	r4,r5,.Leven
 	ld.a	r4,[r0,8]
 	ld.a	r5,[r1,8]
+#ifdef CONFIG_ISA_ARCV2
+.Loop_end:
+	brne	WORD2,r12,.Lodd
+#else
 	brne	WORD2,r12,.Lodd
 .Loop_end:
+#endif
 	asl_s	SHIFT,SHIFT,3
 	bhs_s	.Last_cmp
 	brne	r4,r5,.Leven
@@ -89,7 +107,6 @@
 	bset.cs	r0,r0,31
 .Lodd:
 	cmp_s	WORD2,r12
-
 	mov_s	r0,1
 	j_s.d	[blink]
 	bset.cs	r0,r0,31
@@ -100,14 +117,25 @@
 	ldb	r4,[r0,0]
 	ldb	r5,[r1,0]
 	lsr.f	lp_count,r3
+#ifdef CONFIG_ISA_ARCV2
+	mov	r12,r3
 	lpne	.Lbyte_end
+	brne	r3,r12,.Lbyte_odd
+#else
+	lpne	.Lbyte_end
+#endif
 	ldb_s	r3,[r0,1]
 	ldb	r12,[r1,1]
 	brne	r4,r5,.Lbyte_even
 	ldb.a	r4,[r0,2]
 	ldb.a	r5,[r1,2]
+#ifdef CONFIG_ISA_ARCV2
+.Lbyte_end:
+	brne	r3,r12,.Lbyte_odd
+#else
 	brne	r3,r12,.Lbyte_odd
 .Lbyte_end:
+#endif
 	bcc	.Lbyte_even
 	brne	r4,r5,.Lbyte_even
 	ldb_s	r3,[r0,1]
@@ -121,4 +149,4 @@
 .Lnil:
 	j_s.d	[blink]
 	mov	r0,0
-ARC_EXIT memcmp
+END(memcmp)