The vector dequantization has a test in a loop preventing effective SIMD
implementation. By moving it out of the loop, this loop can be DSPized.

Therefore, modify the current DSP implementation. In particular, the
DSP implementation no longer has to handle null loop sizes.

The decode_hf implementations have following timings:

For x86 Arrandale:
        C  SSE SSE2 SSE4
win32: 260 162  119  104
win64: 242 N/A   89   72

The arm NEON optimizations follow in a later patch as external asm. The
now unused check for the y modifier in arm inline asm is removed from
configure.

Based on a patch from Christophe Gisquet.

Unrolling of the m == 0 case avoids a possible use of the uninitilized
value sum when s->predictor_history is not set. I failed to find a
sample for it. It also reduced the cycle count from 220 to 150 on
sandy bridge, x86_64 linux, gcc 4.8.2 compared to his patch.

Timings for Arrandale:
          C    SSE
win32:  2108   334
win64:  1152   322

Factorizing the inner loop with a call/jmp is a >15 cycles cost, even with
the jmp destination being aligned.

Unrolling for ARCH_X86_64 is a 20 cycles gain.
Signed-off-by: Janne Grunau <janne-libav@jannau.net>

This change is inspired by x86 asm where it frees a register.
Signed-off-by: Janne Grunau <janne-libav@jannau.net>

Results for Arrandale/Windows:
32: 1670 -> 316
64:  728 -> 298
Signed-off-by: Janne Grunau <janne-libav@jannau.net>

The scaling factor is constant so it is faster to scale the
FIR coefficients in the tables during compilation.
Signed-off-by: Janne Grunau <janne-libav@jannau.net>

None of the encoder bits are arch-optimized.

No permutation is necessary for the FDCT.

This also avoids a macro name clash and related warning on ARM.

These are already covered through dependencies specified in configure.

Signed-off-by: Anton Khirnov <anton@khirnov.net>

Based on a patch by Andrew Kelley <superjoe30@gmail.com>
Signed-off-by: Diego Biurrun <diego@biurrun.de>

Signed-off-by: Diego Biurrun <diego@biurrun.de>

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

Framerate is now a sane rational instead of an integer, and
inputDepth is changed to what it actually is.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

Based on x264 code
Signed-off-by: James Almer <jamrial@gmail.com>

Based on x264 code
Signed-off-by: James Almer <jamrial@gmail.com>

Signed-off-by: James Almer <jamrial@gmail.com>

Moving cpunop from the HAVE_LIST to the ARCH_EXT_LIST_X86 has the side
effect of enabling it. The semantics of the check have to be changed
from enable if successful to disable if unsuccessful. This was missing
in 2b0bb699 causing build errors with
nasm.

beta_offset is pre-multiplied by 2.