Write functions to handle loading and saving words a block at a time, taking into

account endian differences.

The current code does not take advantage of the knowledge of which endianness
we are running on; an optimization suggested by Yves Jerschow is to use (unsafe)
casts to speed up the load/store operations. This turns out to provide large
performance increases (30% or more) in some cases.

Even without the unsafe casts, this version seems to average a few percent
faster, probably because the longer loading loops have been partially or
fully unrolled.

This also makes the code implementing low-level algorithms like ciphers and
hashes a bit more succint.

1 files changed, 3 insertions, 4 deletions

diff --git a/src/whrlpool.cpp b/src/whrlpool.cpp
index 48cd79e5f..960095d9b 100644
--- a/src/whrlpool.cpp
+++ b/src/whrlpool.cpp
@@ -22,8 +22,7 @@ void Whirlpool::hash(const byte in[])
    };
 
    for(u32bit j = 0; j != 8; ++j)
-      M[j] = make_u64bit(in[8*j+0], in[8*j+1], in[8*j+2], in[8*j+3],
-                         in[8*j+4], in[8*j+5], in[8*j+6], in[8*j+7]);
+      M[j] = load_be<u64bit>(in, j);
 
    u64bit K0, K1, K2, K3, K4, K5, K6, K7;
    K0 = digest[0]; K1 = digest[1]; K2 = digest[2]; K3 = digest[3];
@@ -124,8 +123,8 @@ void Whirlpool::hash(const byte in[])
 *************************************************/
 void Whirlpool::copy_out(byte output[])
    {
-   for(u32bit j = 0; j != OUTPUT_LENGTH; ++j)
-      output[j] = get_byte(j % 8, digest[j/8]);
+   for(u32bit j = 0; j != OUTPUT_LENGTH; j += 8)
+      store_be(digest[j/8], output + j);
    }
 
 /*************************************************