xtea: invert branch and loop precedence

Should slightly improve performance depending on the compiler used.
This commit is contained in:
Luca Barbato 2012-07-05 09:52:04 +02:00
parent 669bbedfa8
commit f6687bf5f8

View File

@ -71,8 +71,8 @@ void av_xtea_crypt(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int count,
{
int i;
while (count > 0) {
if (decrypt) {
if (decrypt) {
while (count > 0) {
xtea_crypt_ecb(ctx, dst, src, decrypt);
if (iv) {
@ -80,7 +80,13 @@ void av_xtea_crypt(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int count,
dst[i] = dst[i] ^ iv[i];
memcpy(iv, src, 8);
}
} else {
src += 8;
dst += 8;
count -= 8;
}
} else {
while (count > 0) {
if (iv) {
for (i = 0; i < 8; i++)
dst[i] = src[i] ^ iv[i];
@ -89,11 +95,10 @@ void av_xtea_crypt(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int count,
} else {
xtea_crypt_ecb(ctx, dst, src, decrypt);
}
src += 8;
dst += 8;
count -= 8;
}
src += 8;
dst += 8;
count -= 8;
}
}