| 1 | /* |
| 2 | * FFT/IFFT transforms |
| 3 | * AltiVec-enabled |
| 4 | * Copyright (c) 2009 Loren Merritt |
| 5 | * |
| 6 | * This file is part of FFmpeg. |
| 7 | * |
| 8 | * FFmpeg is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU Lesser General Public |
| 10 | * License as published by the Free Software Foundation; either |
| 11 | * version 2.1 of the License, or (at your option) any later version. |
| 12 | * |
| 13 | * FFmpeg is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 | * Lesser General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU Lesser General Public |
| 19 | * License along with FFmpeg; if not, write to the Free Software |
| 20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 21 | */ |
| 22 | |
| 23 | #include "config.h" |
| 24 | #include "libavutil/cpu.h" |
| 25 | #include "libavutil/ppc/cpu.h" |
| 26 | #include "libavutil/ppc/types_altivec.h" |
| 27 | #include "libavutil/ppc/util_altivec.h" |
| 28 | #include "libavcodec/fft.h" |
| 29 | |
| 30 | /** |
| 31 | * Do a complex FFT with the parameters defined in ff_fft_init(). |
| 32 | * The input data must be permuted before with s->revtab table. |
| 33 | * No 1.0 / sqrt(n) normalization is done. |
| 34 | * AltiVec-enabled: |
| 35 | * This code assumes that the 'z' pointer is 16 bytes-aligned. |
| 36 | * It also assumes all FFTComplex are 8 bytes-aligned pairs of floats. |
| 37 | */ |
| 38 | |
| 39 | #if HAVE_VSX |
| 40 | #include "fft_vsx.h" |
| 41 | #else |
| 42 | void ff_fft_calc_altivec(FFTContext *s, FFTComplex *z); |
| 43 | void ff_fft_calc_interleave_altivec(FFTContext *s, FFTComplex *z); |
| 44 | #endif |
| 45 | |
| 46 | #if HAVE_GNU_AS && HAVE_ALTIVEC |
| 47 | static void imdct_half_altivec(FFTContext *s, FFTSample *output, const FFTSample *input) |
| 48 | { |
| 49 | int j, k; |
| 50 | int n = 1 << s->mdct_bits; |
| 51 | int n4 = n >> 2; |
| 52 | int n8 = n >> 3; |
| 53 | int n32 = n >> 5; |
| 54 | const uint16_t *revtabj = s->revtab; |
| 55 | const uint16_t *revtabk = s->revtab+n4; |
| 56 | const vec_f *tcos = (const vec_f*)(s->tcos+n8); |
| 57 | const vec_f *tsin = (const vec_f*)(s->tsin+n8); |
| 58 | const vec_f *pin = (const vec_f*)(input+n4); |
| 59 | vec_f *pout = (vec_f*)(output+n4); |
| 60 | |
| 61 | /* pre rotation */ |
| 62 | k = n32-1; |
| 63 | do { |
| 64 | vec_f cos,sin,cos0,sin0,cos1,sin1,re,im,r0,i0,r1,i1,a,b,c,d; |
| 65 | #define CMULA(p,o0,o1,o2,o3)\ |
| 66 | a = pin[ k*2+p]; /* { z[k].re, z[k].im, z[k+1].re, z[k+1].im } */\ |
| 67 | b = pin[-k*2-p-1]; /* { z[-k-2].re, z[-k-2].im, z[-k-1].re, z[-k-1].im } */\ |
| 68 | re = vec_perm(a, b, vcprm(0,2,s0,s2)); /* { z[k].re, z[k+1].re, z[-k-2].re, z[-k-1].re } */\ |
| 69 | im = vec_perm(a, b, vcprm(s3,s1,3,1)); /* { z[-k-1].im, z[-k-2].im, z[k+1].im, z[k].im } */\ |
| 70 | cos = vec_perm(cos0, cos1, vcprm(o0,o1,s##o2,s##o3)); /* { cos[k], cos[k+1], cos[-k-2], cos[-k-1] } */\ |
| 71 | sin = vec_perm(sin0, sin1, vcprm(o0,o1,s##o2,s##o3));\ |
| 72 | r##p = im*cos - re*sin;\ |
| 73 | i##p = re*cos + im*sin; |
| 74 | #define STORE2(v,dst)\ |
| 75 | j = dst;\ |
| 76 | vec_ste(v, 0, output+j*2);\ |
| 77 | vec_ste(v, 4, output+j*2); |
| 78 | #define STORE8(p)\ |
| 79 | a = vec_perm(r##p, i##p, vcprm(0,s0,0,s0));\ |
| 80 | b = vec_perm(r##p, i##p, vcprm(1,s1,1,s1));\ |
| 81 | c = vec_perm(r##p, i##p, vcprm(2,s2,2,s2));\ |
| 82 | d = vec_perm(r##p, i##p, vcprm(3,s3,3,s3));\ |
| 83 | STORE2(a, revtabk[ p*2-4]);\ |
| 84 | STORE2(b, revtabk[ p*2-3]);\ |
| 85 | STORE2(c, revtabj[-p*2+2]);\ |
| 86 | STORE2(d, revtabj[-p*2+3]); |
| 87 | |
| 88 | cos0 = tcos[k]; |
| 89 | sin0 = tsin[k]; |
| 90 | cos1 = tcos[-k-1]; |
| 91 | sin1 = tsin[-k-1]; |
| 92 | CMULA(0, 0,1,2,3); |
| 93 | CMULA(1, 2,3,0,1); |
| 94 | STORE8(0); |
| 95 | STORE8(1); |
| 96 | revtabj += 4; |
| 97 | revtabk -= 4; |
| 98 | k--; |
| 99 | } while(k >= 0); |
| 100 | |
| 101 | #if HAVE_VSX |
| 102 | ff_fft_calc_vsx(s, (FFTComplex*)output); |
| 103 | #else |
| 104 | ff_fft_calc_altivec(s, (FFTComplex*)output); |
| 105 | #endif |
| 106 | |
| 107 | /* post rotation + reordering */ |
| 108 | j = -n32; |
| 109 | k = n32-1; |
| 110 | do { |
| 111 | vec_f cos,sin,re,im,a,b,c,d; |
| 112 | #define CMULB(d0,d1,o)\ |
| 113 | re = pout[o*2];\ |
| 114 | im = pout[o*2+1];\ |
| 115 | cos = tcos[o];\ |
| 116 | sin = tsin[o];\ |
| 117 | d0 = im*sin - re*cos;\ |
| 118 | d1 = re*sin + im*cos; |
| 119 | |
| 120 | CMULB(a,b,j); |
| 121 | CMULB(c,d,k); |
| 122 | pout[2*j] = vec_perm(a, d, vcprm(0,s3,1,s2)); |
| 123 | pout[2*j+1] = vec_perm(a, d, vcprm(2,s1,3,s0)); |
| 124 | pout[2*k] = vec_perm(c, b, vcprm(0,s3,1,s2)); |
| 125 | pout[2*k+1] = vec_perm(c, b, vcprm(2,s1,3,s0)); |
| 126 | j++; |
| 127 | k--; |
| 128 | } while(k >= 0); |
| 129 | } |
| 130 | |
| 131 | static void imdct_calc_altivec(FFTContext *s, FFTSample *output, const FFTSample *input) |
| 132 | { |
| 133 | int k; |
| 134 | int n = 1 << s->mdct_bits; |
| 135 | int n4 = n >> 2; |
| 136 | int n16 = n >> 4; |
| 137 | vec_u32 sign = {1U<<31,1U<<31,1U<<31,1U<<31}; |
| 138 | vec_u32 *p0 = (vec_u32*)(output+n4); |
| 139 | vec_u32 *p1 = (vec_u32*)(output+n4*3); |
| 140 | |
| 141 | imdct_half_altivec(s, output + n4, input); |
| 142 | |
| 143 | for (k = 0; k < n16; k++) { |
| 144 | vec_u32 a = p0[k] ^ sign; |
| 145 | vec_u32 b = p1[-k-1]; |
| 146 | p0[-k-1] = vec_perm(a, a, vcprm(3,2,1,0)); |
| 147 | p1[k] = vec_perm(b, b, vcprm(3,2,1,0)); |
| 148 | } |
| 149 | } |
| 150 | #endif /* HAVE_GNU_AS && HAVE_ALTIVEC */ |
| 151 | |
| 152 | av_cold void ff_fft_init_ppc(FFTContext *s) |
| 153 | { |
| 154 | #if HAVE_GNU_AS && HAVE_ALTIVEC |
| 155 | if (!PPC_ALTIVEC(av_get_cpu_flags())) |
| 156 | return; |
| 157 | |
| 158 | #if HAVE_VSX |
| 159 | s->fft_calc = ff_fft_calc_interleave_vsx; |
| 160 | #else |
| 161 | s->fft_calc = ff_fft_calc_interleave_altivec; |
| 162 | #endif |
| 163 | if (s->mdct_bits >= 5) { |
| 164 | s->imdct_calc = imdct_calc_altivec; |
| 165 | s->imdct_half = imdct_half_altivec; |
| 166 | } |
| 167 | #endif /* HAVE_GNU_AS && HAVE_ALTIVEC */ |
| 168 | } |