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[U-Boot,01/12] arc: memcmp - fix zero-delay loop utilization

Message ID 1422961100-1618-2-git-send-email-abrodkin@synopsys.com
State Accepted, archived
Delegated to: Alexey Brodkin
Headers show

Commit Message

Alexey Brodkin Feb. 3, 2015, 10:58 a.m. UTC 
From: Igor Guryanov <guryanov@synopsys.com>

It's prohibited to put branch instruction in the very end of zero-delay
loop. On execution this causes "Illegal instruction" exception.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Igor Guryanov <guryanov@synopsys.com>
---
 arch/arc/lib/memcmp.S | 2 ++
 1 file changed, 2 insertions(+)
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Patch

diff --git a/arch/arc/lib/memcmp.S b/arch/arc/lib/memcmp.S
index fa5aac5..87bccab 100644
--- a/arch/arc/lib/memcmp.S
+++ b/arch/arc/lib/memcmp.S
@@ -29,6 +29,7 @@  memcmp:
 	ld.a	%r4, [%r0, 8]
 	ld.a	%r5, [%r1, 8]
 	brne	WORD2, %r12, .Lodd
+	nop
 .Loop_end:
 	asl_s	SHIFT, SHIFT, 3
 	bhs_s	.Last_cmp
@@ -105,6 +106,7 @@  memcmp:
 	ldb.a	%r4, [%r0, 2]
 	ldb.a	%r5, [%r1, 2]
 	brne	%r3, %r12, .Lbyte_odd
+	nop
 .Lbyte_end:
 	bcc	.Lbyte_even
 	brne	%r4, %r5, .Lbyte_even