oysteikt/mpd
0
0
Fork 0
Code Issues Pull Requests Releases Activity

decoder/dsf: simplify dsf_to_pcm_order()

Browse Source 
Don't pass the buffer size to the function, as it's known at compile
time.  Use "restrict" on the pointer arguments, and merge the two
loops, which allows the compiler to optimize this loop with a few SSE2
instructions.
This commit is contained in:
Max Kellermann 2014-08-22 06:58:08 +02:00
parent dedc2986c6
commit d8782ce5fd
1 changed files with 5 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
src/decoder/plugins/DsfDecoderPlugin.cxx
View File

@ -195,16 +195,11 @@ bit_reverse_buffer(uint8_t *p, uint8_t *end)
* order.
*/
static void
dsf_to_pcm_order(uint8_t *dest, const uint8_t *src, size_t nrbytes)
dsf_to_pcm_order(uint8_t *gcc_restrict dest, const uint8_t *gcc_restrict src)
{
for (size_t i = 0, j = 0; i < nrbytes; i += 2) {
dest[i] = src[j];
j++;
}
for (size_t i = 1, j = 0; i < nrbytes; i += 2) {
dest[i] = src[DSF_BLOCK_SIZE + j];
j++;
for (size_t i = 0; i < DSF_BLOCK_SIZE; ++i) {
dest[2 * i] = src[i];
dest[2 * i + 1] = src[DSF_BLOCK_SIZE + i];
}
}
@ -236,7 +231,7 @@ dsf_decode_chunk(Decoder &decoder, InputStream &is,
bit_reverse_buffer(buffer, buffer + block_size);
uint8_t interleaved_buffer[DSF_BLOCK_SIZE * 2];
dsf_to_pcm_order(interleaved_buffer, buffer, block_size);
dsf_to_pcm_order(interleaved_buffer, buffer);
const auto cmd = decoder_data(decoder, is,
interleaved_buffer, block_size,