Audio: Mixer: Add hifi version processing functions for mixer

[andrula-song]

Add hifi3 & hifi4 version implementation of mixer processing functions.
The hifi version functions can save at least 47% cycles than C version.

Signed-off-by: Andrula Song xiaoyuan.song@intel.com

[andrula-song]

Since hifi3 and hifi4 will use the same instructions, so named the hifi version of mixer as mixer_hifi.c.
compared with the original C version, the functions can save at least 47% cycles, here is the result:
mix_n_s16 can save about 67% cycles than C version;
mix_n_s24 can save about 51% cycles than C version;
mix_n_s32 can save about 47% cycles than C version;

[XiaoyunWu6666]

SOFCI_TEST

[XiaoyunWu6666]

SOFCI TEST

[ShriramShastry]

Is it possible to add check for __Pragma("no unroll"), __Pragma("no reorder"), and __Pragma("no simd") in the for loop?

[lgirdwood]

Is it possible to add check for __Pragma("no unroll"), __Pragma("no reorder"), and __Pragma("no simd") in the for loop?

Why ?

[ShriramShastry]

Is it possible to add check for __Pragma("no unroll"), __Pragma("no reorder"), and __Pragma("no simd") in the for loop?

Why ?

It appears to aid optimization by providing additional information to the compiler.

[ From HiFi User Guide documentation ]
3.4 Standard C/C++ Auto-Vectorization
Auto-vectorization of scalar C code can produce effective results on simple loop nests, but has its limits. It can be improved through the use of compiler pragmas and options, and effective data marshalling to make data accesses (loads and stores) regular and aligned.

Pragma is widely used in Nature DSP Library functions.

[lgirdwood]

Is it possible to add check for __Pragma("no unroll"), __Pragma("no reorder"), and __Pragma("no simd") in the for loop?

Why ?

It appears to aid optimization by providing additional information to the compiler.

That's correct, but in this case @andrula-song is hand writing the intrinsics and the loops are complex. The autovectorizer works best on simple small loops, and the pragma suggestions above are not applicable here (and would probably make performance worse).

[singalsu]

Great HiFi optimization work! Some small issues only:

[lyakh]

approval condition to addressing comments from @singalsu of course

[andrula-song]

hi @wszypelt , can you help to check internel CI? Thanks.

[lgirdwood]

@lrudyX can you check CI, its showing a blank page. Thanks !

[andrula-song]

SOFCI_TEST