From ae3ba0858cd4e9e0afdf5a4dbfdae1c196986ad6 Mon Sep 17 00:00:00 2001
From: Moinak Ghosh <moinakg@gmail.com>
Date: Sat, 29 Jun 2013 19:42:45 +0530
Subject: [PATCH] Avoid CRC64 for Similarity IDs when using 256-bit hash.

---
 rabin/rabin_dedup.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/rabin/rabin_dedup.c b/rabin/rabin_dedup.c
index c9eebc3..1739d6c 100755
--- a/rabin/rabin_dedup.c
+++ b/rabin/rabin_dedup.c
@@ -1041,11 +1041,19 @@ process_blocks:
 					increment = cfg->chunk_cksum_sz / 2;
 					if  (increment * sub_i > length)
 						sub_i = length / increment;
-					for (j = 0; j<sub_i; j++) {
-						crc = lzma_crc64(tgt, increment/2, 0);
-						*((uint64_t *)sim_ck) = crc;
-						tgt += increment;
-						sim_ck += cfg->similarity_cksum_sz;
+					if (increment/2 == sizeof (uint64_t)) {
+						for (j = 0; j<sub_i; j++) {
+							*((uint64_t *)sim_ck) = *((uint64_t *)tgt);
+							tgt += increment;
+							sim_ck += cfg->similarity_cksum_sz;
+						}
+					} else {
+						for (j = 0; j<sub_i; j++) {
+							crc = lzma_crc64(tgt, increment/2, 0);
+							*((uint64_t *)sim_ck) = crc;
+							tgt += increment;
+							sim_ck += cfg->similarity_cksum_sz;
+						}
 					}
 
 					/*