Alc/mixer/mixer_sse2.c

   1 /**
   2  * OpenAL cross platform audio library
   3  * Copyright (C) 2014 by Timothy Arceri <t_arceri@yahoo.com.au>.
   4  * This library is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU Library General Public
   6  *  License as published by the Free Software Foundation; either
   7  *  version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *  Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  *  License along with this library; if not, write to the
  16  *  Free Software Foundation, Inc.,
  17  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  * Or go to http://www.gnu.org/copyleft/lgpl.html
  19  */
  20
  21 #include "config.h"
  22
  23 #include <xmmintrin.h>
  24 #include <emmintrin.h>
  25
  26 #include "alu.h"
  27 #include "defs.h"
  28
  29
  30 const ALfloat *Resample_lerp_SSE2(const InterpState* UNUSED(state),
  31   const ALfloat *restrict src, ALsizei frac, ALint increment,
  32   ALfloat *restrict dst, ALsizei numsamples)
  33 {
  34     const __m128i increment4 = _mm_set1_epi32(increment*4);
  35     const __m128 fracOne4 = _mm_set1_ps(1.0f/FRACTIONONE);
  36     const __m128i fracMask4 = _mm_set1_epi32(FRACTIONMASK);
  37     union { alignas(16) ALint i[4]; float f[4]; } pos_;
  38     union { alignas(16) ALsizei i[4]; float f[4]; } frac_;
  39     __m128i frac4, pos4;
  40     ALint pos;
  41     ALsizei i;
  42
  43     ASSUME(numsamples > 0);
  44
  45     InitiatePositionArrays(frac, increment, frac_.i, pos_.i, 4);
  46
  47     frac4 = _mm_castps_si128(_mm_load_ps(frac_.f));
  48     pos4 = _mm_castps_si128(_mm_load_ps(pos_.f));
  49
  50     for(i = 0;numsamples-i > 3;i += 4)
  51     {
  52         const __m128 val1 = _mm_setr_ps(src[pos_.i[0]  ], src[pos_.i[1]  ], src[pos_.i[2]  ], src[pos_.i[3]  ]);
  53         const __m128 val2 = _mm_setr_ps(src[pos_.i[0]+1], src[pos_.i[1]+1], src[pos_.i[2]+1], src[pos_.i[3]+1]);
  54
  55         /* val1 + (val2-val1)*mu */
  56         const __m128 r0 = _mm_sub_ps(val2, val1);
  57         const __m128 mu = _mm_mul_ps(_mm_cvtepi32_ps(frac4), fracOne4);
  58         const __m128 out = _mm_add_ps(val1, _mm_mul_ps(mu, r0));
  59
  60         _mm_store_ps(&dst[i], out);
  61
  62         frac4 = _mm_add_epi32(frac4, increment4);
  63         pos4 = _mm_add_epi32(pos4, _mm_srli_epi32(frac4, FRACTIONBITS));
  64         frac4 = _mm_and_si128(frac4, fracMask4);
  65
  66         pos_.i[0] = _mm_cvtsi128_si32(_mm_shuffle_epi32(pos4, _MM_SHUFFLE(0, 0, 0, 0)));
  67         pos_.i[1] = _mm_cvtsi128_si32(_mm_shuffle_epi32(pos4, _MM_SHUFFLE(1, 1, 1, 1)));
  68         pos_.i[2] = _mm_cvtsi128_si32(_mm_shuffle_epi32(pos4, _MM_SHUFFLE(2, 2, 2, 2)));
  69         pos_.i[3] = _mm_cvtsi128_si32(_mm_shuffle_epi32(pos4, _MM_SHUFFLE(3, 3, 3, 3)));
  70     }
  71
  72     /* NOTE: These four elements represent the position *after* the last four
  73      * samples, so the lowest element is the next position to resample.
  74      */
  75     pos = pos_.i[0];
  76     frac = _mm_cvtsi128_si32(frac4);
  77
  78     for(;i < numsamples;i++)
  79     {
  80         dst[i] = lerp(src[pos], src[pos+1], frac * (1.0f/FRACTIONONE));
  81
  82         frac += increment;
  83         pos  += frac>>FRACTIONBITS;
  84         frac &= FRACTIONMASK;
  85     }
  86     return dst;
  87 }