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lpc.c
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1 /*
2  * MMX optimized LPC DSP utils
3  * Copyright (c) 2007 Loren Merritt
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/x86/asm.h"
23 #include "libavutil/attributes.h"
24 #include "libavutil/cpu.h"
25 #include "libavutil/mem.h"
26 #include "libavcodec/lpc.h"
27 
28 DECLARE_ASM_CONST(16, double, pd_1)[2] = { 1.0, 1.0 };
29 DECLARE_ASM_CONST(16, double, pd_2)[2] = { 2.0, 2.0 };
30 
31 #if HAVE_SSE2_INLINE
32 
33 static void lpc_apply_welch_window_sse2(const int32_t *data, int len,
34  double *w_data)
35 {
36  double c = 2.0 / (len-1.0);
37  int n2 = len>>1;
38  x86_reg i = -n2*sizeof(int32_t);
39  x86_reg j = n2*sizeof(int32_t);
40  __asm__ volatile(
41  "movsd %4, %%xmm7 \n\t"
42  "movapd "MANGLE(pd_1)", %%xmm6 \n\t"
43  "movapd "MANGLE(pd_2)", %%xmm5 \n\t"
44  "movlhps %%xmm7, %%xmm7 \n\t"
45  "subpd %%xmm5, %%xmm7 \n\t"
46  "addsd %%xmm6, %%xmm7 \n\t"
47  "test $1, %5 \n\t"
48  "jz 2f \n\t"
49 #define WELCH(MOVPD, offset)\
50  "1: \n\t"\
51  "movapd %%xmm7, %%xmm1 \n\t"\
52  "mulpd %%xmm1, %%xmm1 \n\t"\
53  "movapd %%xmm6, %%xmm0 \n\t"\
54  "subpd %%xmm1, %%xmm0 \n\t"\
55  "pshufd $0x4e, %%xmm0, %%xmm1 \n\t"\
56  "cvtpi2pd (%3,%0), %%xmm2 \n\t"\
57  "cvtpi2pd "#offset"*4(%3,%1), %%xmm3 \n\t"\
58  "mulpd %%xmm0, %%xmm2 \n\t"\
59  "mulpd %%xmm1, %%xmm3 \n\t"\
60  "movapd %%xmm2, (%2,%0,2) \n\t"\
61  MOVPD" %%xmm3, "#offset"*8(%2,%1,2) \n\t"\
62  "subpd %%xmm5, %%xmm7 \n\t"\
63  "sub $8, %1 \n\t"\
64  "add $8, %0 \n\t"\
65  "jl 1b \n\t"\
66 
67  WELCH("movupd", -1)
68  "jmp 3f \n\t"
69  "2: \n\t"
70  WELCH("movapd", -2)
71  "3: \n\t"
72  :"+&r"(i), "+&r"(j)
73  :"r"(w_data+n2), "r"(data+n2), "m"(c), "r"(len)
74  XMM_CLOBBERS_ONLY("%xmm0", "%xmm1", "%xmm2", "%xmm3",
75  "%xmm5", "%xmm6", "%xmm7")
76  );
77 #undef WELCH
78 }
79 
80 static void lpc_compute_autocorr_sse2(const double *data, int len, int lag,
81  double *autoc)
82 {
83  int j;
84 
85  if((x86_reg)data & 15)
86  data++;
87 
88  for(j=0; j<lag; j+=2){
89  x86_reg i = -len*sizeof(double);
90  if(j == lag-2) {
91  __asm__ volatile(
92  "movsd "MANGLE(pd_1)", %%xmm0 \n\t"
93  "movsd "MANGLE(pd_1)", %%xmm1 \n\t"
94  "movsd "MANGLE(pd_1)", %%xmm2 \n\t"
95  "1: \n\t"
96  "movapd (%2,%0), %%xmm3 \n\t"
97  "movupd -8(%3,%0), %%xmm4 \n\t"
98  "movapd (%3,%0), %%xmm5 \n\t"
99  "mulpd %%xmm3, %%xmm4 \n\t"
100  "mulpd %%xmm3, %%xmm5 \n\t"
101  "mulpd -16(%3,%0), %%xmm3 \n\t"
102  "addpd %%xmm4, %%xmm1 \n\t"
103  "addpd %%xmm5, %%xmm0 \n\t"
104  "addpd %%xmm3, %%xmm2 \n\t"
105  "add $16, %0 \n\t"
106  "jl 1b \n\t"
107  "movhlps %%xmm0, %%xmm3 \n\t"
108  "movhlps %%xmm1, %%xmm4 \n\t"
109  "movhlps %%xmm2, %%xmm5 \n\t"
110  "addsd %%xmm3, %%xmm0 \n\t"
111  "addsd %%xmm4, %%xmm1 \n\t"
112  "addsd %%xmm5, %%xmm2 \n\t"
113  "movsd %%xmm0, (%1) \n\t"
114  "movsd %%xmm1, 8(%1) \n\t"
115  "movsd %%xmm2, 16(%1) \n\t"
116  :"+&r"(i)
117  :"r"(autoc+j), "r"(data+len), "r"(data+len-j)
118  :"memory"
119  );
120  } else {
121  __asm__ volatile(
122  "movsd "MANGLE(pd_1)", %%xmm0 \n\t"
123  "movsd "MANGLE(pd_1)", %%xmm1 \n\t"
124  "1: \n\t"
125  "movapd (%3,%0), %%xmm3 \n\t"
126  "movupd -8(%4,%0), %%xmm4 \n\t"
127  "mulpd %%xmm3, %%xmm4 \n\t"
128  "mulpd (%4,%0), %%xmm3 \n\t"
129  "addpd %%xmm4, %%xmm1 \n\t"
130  "addpd %%xmm3, %%xmm0 \n\t"
131  "add $16, %0 \n\t"
132  "jl 1b \n\t"
133  "movhlps %%xmm0, %%xmm3 \n\t"
134  "movhlps %%xmm1, %%xmm4 \n\t"
135  "addsd %%xmm3, %%xmm0 \n\t"
136  "addsd %%xmm4, %%xmm1 \n\t"
137  "movsd %%xmm0, %1 \n\t"
138  "movsd %%xmm1, %2 \n\t"
139  :"+&r"(i), "=m"(autoc[j]), "=m"(autoc[j+1])
140  :"r"(data+len), "r"(data+len-j)
141  );
142  }
143  }
144 }
145 
146 #endif /* HAVE_SSE2_INLINE */
147 
149 {
150 #if HAVE_SSE2_INLINE
151  int mm_flags = av_get_cpu_flags();
152 
153  if (mm_flags & (AV_CPU_FLAG_SSE2|AV_CPU_FLAG_SSE2SLOW)) {
154  c->lpc_apply_welch_window = lpc_apply_welch_window_sse2;
155  c->lpc_compute_autocorr = lpc_compute_autocorr_sse2;
156  }
157 #endif /* HAVE_SSE2_INLINE */
158 }