Speed up md5 hash filling/verifying by 20%

[fio.git] / md5.c

diff --git a/md5.c b/md5.c
index cf1f814a0d63c2cee558c8049140156e90f9723c..6b61012e85da005d418a7c4ea1ef22349038ed82 100644 (file)
--- a/md5.c
+++ b/md5.c
@@ -9,10 +9,11 @@ static void md5_transform(uint32_t *hash, uint32_t const *in)
 {
        uint32_t a, b, c, d;
 
-       a = hash[0];
-       b = hash[1];
-       c = hash[2];
-       d = hash[3];
+       /*
+        * This used to be set from the hash[0..3] input, but we can
+        * skip a memory clear if we just start from 0 instead.
+        */
+       a = b = c = d = 0;
 
        MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
        MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
@@ -82,10 +83,10 @@ static void md5_transform(uint32_t *hash, uint32_t const *in)
        MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
        MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
 
-       hash[0] += a;
-       hash[1] += b;
-       hash[2] += c;
-       hash[3] += d;
+       hash[0] = a;
+       hash[1] = b;
+       hash[2] = c;
+       hash[3] = d;
 }
 
 void md5_update(struct md5_ctx *mctx, const uint8_t *data, unsigned int len)