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, 2 deletions

diff --git a/src/randpool.cpp b/src/randpool.cpp
index e041cf873..ed60b385a 100644
--- a/src/randpool.cpp
+++ b/src/randpool.cpp
@@ -9,6 +9,8 @@
 #include <botan/util.h>
 #include <algorithm>
 
+#include <assert.h>
+
 namespace Botan {
 
 namespace {
@@ -63,8 +65,7 @@ void Randpool::update_buffer()
    for(u32bit j = 0; j != counter.size(); ++j)
       if(++counter[j])
          break;
-   for(u32bit j = 0; j != 8; ++j)
-      counter[j+4] = get_byte(j, timestamp);
+   store_be(timestamp, counter + 4);
 
    SecureVector<byte> mac_val = randpool_prf(mac, GEN_OUTPUT,
                                              counter, counter.size());