| /* |
| * FFT/IFFT transforms |
| * AltiVec-enabled |
| * Copyright (c) 2009 Loren Merritt |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #include "config.h" |
| #include "libavutil/cpu.h" |
| #include "libavutil/ppc/cpu.h" |
| #include "libavutil/ppc/types_altivec.h" |
| #include "libavutil/ppc/util_altivec.h" |
| #include "libavcodec/fft.h" |
| |
| /** |
| * Do a complex FFT with the parameters defined in ff_fft_init(). |
| * The input data must be permuted before with s->revtab table. |
| * No 1.0 / sqrt(n) normalization is done. |
| * AltiVec-enabled: |
| * This code assumes that the 'z' pointer is 16 bytes-aligned. |
| * It also assumes all FFTComplex are 8 bytes-aligned pairs of floats. |
| */ |
| |
| #if HAVE_VSX |
| #include "fft_vsx.h" |
| #else |
| void ff_fft_calc_altivec(FFTContext *s, FFTComplex *z); |
| void ff_fft_calc_interleave_altivec(FFTContext *s, FFTComplex *z); |
| #endif |
| |
| #if HAVE_GNU_AS && HAVE_ALTIVEC |
| static void imdct_half_altivec(FFTContext *s, FFTSample *output, const FFTSample *input) |
| { |
| int j, k; |
| int n = 1 << s->mdct_bits; |
| int n4 = n >> 2; |
| int n8 = n >> 3; |
| int n32 = n >> 5; |
| const uint16_t *revtabj = s->revtab; |
| const uint16_t *revtabk = s->revtab+n4; |
| const vec_f *tcos = (const vec_f*)(s->tcos+n8); |
| const vec_f *tsin = (const vec_f*)(s->tsin+n8); |
| const vec_f *pin = (const vec_f*)(input+n4); |
| vec_f *pout = (vec_f*)(output+n4); |
| |
| /* pre rotation */ |
| k = n32-1; |
| do { |
| vec_f cos,sin,cos0,sin0,cos1,sin1,re,im,r0,i0,r1,i1,a,b,c,d; |
| #define CMULA(p,o0,o1,o2,o3)\ |
| a = pin[ k*2+p]; /* { z[k].re, z[k].im, z[k+1].re, z[k+1].im } */\ |
| b = pin[-k*2-p-1]; /* { z[-k-2].re, z[-k-2].im, z[-k-1].re, z[-k-1].im } */\ |
| 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 } */\ |
| 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 } */\ |
| cos = vec_perm(cos0, cos1, vcprm(o0,o1,s##o2,s##o3)); /* { cos[k], cos[k+1], cos[-k-2], cos[-k-1] } */\ |
| sin = vec_perm(sin0, sin1, vcprm(o0,o1,s##o2,s##o3));\ |
| r##p = im*cos - re*sin;\ |
| i##p = re*cos + im*sin; |
| #define STORE2(v,dst)\ |
| j = dst;\ |
| vec_ste(v, 0, output+j*2);\ |
| vec_ste(v, 4, output+j*2); |
| #define STORE8(p)\ |
| a = vec_perm(r##p, i##p, vcprm(0,s0,0,s0));\ |
| b = vec_perm(r##p, i##p, vcprm(1,s1,1,s1));\ |
| c = vec_perm(r##p, i##p, vcprm(2,s2,2,s2));\ |
| d = vec_perm(r##p, i##p, vcprm(3,s3,3,s3));\ |
| STORE2(a, revtabk[ p*2-4]);\ |
| STORE2(b, revtabk[ p*2-3]);\ |
| STORE2(c, revtabj[-p*2+2]);\ |
| STORE2(d, revtabj[-p*2+3]); |
| |
| cos0 = tcos[k]; |
| sin0 = tsin[k]; |
| cos1 = tcos[-k-1]; |
| sin1 = tsin[-k-1]; |
| CMULA(0, 0,1,2,3); |
| CMULA(1, 2,3,0,1); |
| STORE8(0); |
| STORE8(1); |
| revtabj += 4; |
| revtabk -= 4; |
| k--; |
| } while(k >= 0); |
| |
| #if HAVE_VSX |
| ff_fft_calc_vsx(s, (FFTComplex*)output); |
| #else |
| ff_fft_calc_altivec(s, (FFTComplex*)output); |
| #endif |
| |
| /* post rotation + reordering */ |
| j = -n32; |
| k = n32-1; |
| do { |
| vec_f cos,sin,re,im,a,b,c,d; |
| #define CMULB(d0,d1,o)\ |
| re = pout[o*2];\ |
| im = pout[o*2+1];\ |
| cos = tcos[o];\ |
| sin = tsin[o];\ |
| d0 = im*sin - re*cos;\ |
| d1 = re*sin + im*cos; |
| |
| CMULB(a,b,j); |
| CMULB(c,d,k); |
| pout[2*j] = vec_perm(a, d, vcprm(0,s3,1,s2)); |
| pout[2*j+1] = vec_perm(a, d, vcprm(2,s1,3,s0)); |
| pout[2*k] = vec_perm(c, b, vcprm(0,s3,1,s2)); |
| pout[2*k+1] = vec_perm(c, b, vcprm(2,s1,3,s0)); |
| j++; |
| k--; |
| } while(k >= 0); |
| } |
| |
| static void imdct_calc_altivec(FFTContext *s, FFTSample *output, const FFTSample *input) |
| { |
| int k; |
| int n = 1 << s->mdct_bits; |
| int n4 = n >> 2; |
| int n16 = n >> 4; |
| vec_u32 sign = {1U<<31,1U<<31,1U<<31,1U<<31}; |
| vec_u32 *p0 = (vec_u32*)(output+n4); |
| vec_u32 *p1 = (vec_u32*)(output+n4*3); |
| |
| imdct_half_altivec(s, output + n4, input); |
| |
| for (k = 0; k < n16; k++) { |
| vec_u32 a = p0[k] ^ sign; |
| vec_u32 b = p1[-k-1]; |
| p0[-k-1] = vec_perm(a, a, vcprm(3,2,1,0)); |
| p1[k] = vec_perm(b, b, vcprm(3,2,1,0)); |
| } |
| } |
| #endif /* HAVE_GNU_AS && HAVE_ALTIVEC */ |
| |
| av_cold void ff_fft_init_ppc(FFTContext *s) |
| { |
| #if HAVE_GNU_AS && HAVE_ALTIVEC |
| if (!PPC_ALTIVEC(av_get_cpu_flags())) |
| return; |
| |
| #if HAVE_VSX |
| s->fft_calc = ff_fft_calc_interleave_vsx; |
| #else |
| s->fft_calc = ff_fft_calc_interleave_altivec; |
| #endif |
| if (s->mdct_bits >= 5) { |
| s->imdct_calc = imdct_calc_altivec; |
| s->imdct_half = imdct_half_altivec; |
| } |
| #endif /* HAVE_GNU_AS && HAVE_ALTIVEC */ |
| } |