FFmpeg
lpc_init.c
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1 /*
2  * SIMD-optimized LPC functions
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/attributes.h"
23 #include "libavutil/x86/asm.h"
24 #include "libavutil/x86/cpu.h"
25 #include "libavcodec/lpc.h"
26 
27 void ff_lpc_apply_welch_window_sse2(const int32_t *data, ptrdiff_t len,
28  double *w_data);
29 void ff_lpc_apply_welch_window_avx2(const int32_t *data, ptrdiff_t len,
30  double *w_data);
31 
32 DECLARE_ASM_CONST(16, double, pd_1)[2] = { 1.0, 1.0 };
33 
34 #if HAVE_SSE2_INLINE
35 
36 static void lpc_compute_autocorr_sse2(const double *data, ptrdiff_t len, int lag,
37  double *autoc)
38 {
39  int j;
40 
41  if((x86_reg)data & 15)
42  data++;
43 
44  for(j=0; j<lag; j+=2){
45  x86_reg i = -len*sizeof(double);
46  if(j == lag-2) {
47  __asm__ volatile(
48  "movsd "MANGLE(pd_1)", %%xmm0 \n\t"
49  "movsd "MANGLE(pd_1)", %%xmm1 \n\t"
50  "movsd "MANGLE(pd_1)", %%xmm2 \n\t"
51  "1: \n\t"
52  "movapd (%2,%0), %%xmm3 \n\t"
53  "movupd -8(%3,%0), %%xmm4 \n\t"
54  "movapd (%3,%0), %%xmm5 \n\t"
55  "mulpd %%xmm3, %%xmm4 \n\t"
56  "mulpd %%xmm3, %%xmm5 \n\t"
57  "mulpd -16(%3,%0), %%xmm3 \n\t"
58  "addpd %%xmm4, %%xmm1 \n\t"
59  "addpd %%xmm5, %%xmm0 \n\t"
60  "addpd %%xmm3, %%xmm2 \n\t"
61  "add $16, %0 \n\t"
62  "jl 1b \n\t"
63  "movhlps %%xmm0, %%xmm3 \n\t"
64  "movhlps %%xmm1, %%xmm4 \n\t"
65  "movhlps %%xmm2, %%xmm5 \n\t"
66  "addsd %%xmm3, %%xmm0 \n\t"
67  "addsd %%xmm4, %%xmm1 \n\t"
68  "addsd %%xmm5, %%xmm2 \n\t"
69  "movsd %%xmm0, (%1) \n\t"
70  "movsd %%xmm1, 8(%1) \n\t"
71  "movsd %%xmm2, 16(%1) \n\t"
72  :"+&r"(i)
73  :"r"(autoc+j), "r"(data+len), "r"(data+len-j)
75  :"memory"
76  );
77  } else {
78  __asm__ volatile(
79  "movsd "MANGLE(pd_1)", %%xmm0 \n\t"
80  "movsd "MANGLE(pd_1)", %%xmm1 \n\t"
81  "1: \n\t"
82  "movapd (%3,%0), %%xmm3 \n\t"
83  "movupd -8(%4,%0), %%xmm4 \n\t"
84  "mulpd %%xmm3, %%xmm4 \n\t"
85  "mulpd (%4,%0), %%xmm3 \n\t"
86  "addpd %%xmm4, %%xmm1 \n\t"
87  "addpd %%xmm3, %%xmm0 \n\t"
88  "add $16, %0 \n\t"
89  "jl 1b \n\t"
90  "movhlps %%xmm0, %%xmm3 \n\t"
91  "movhlps %%xmm1, %%xmm4 \n\t"
92  "addsd %%xmm3, %%xmm0 \n\t"
93  "addsd %%xmm4, %%xmm1 \n\t"
94  "movsd %%xmm0, %1 \n\t"
95  "movsd %%xmm1, %2 \n\t"
96  :"+&r"(i), "=m"(autoc[j]), "=m"(autoc[j+1])
97  :"r"(data+len), "r"(data+len-j)
99  );
100  }
101  }
102 }
103 
104 #endif /* HAVE_SSE2_INLINE */
105 
107 {
108  int cpu_flags = av_get_cpu_flags();
109 
110 #if HAVE_SSE2_INLINE
112  c->lpc_compute_autocorr = lpc_compute_autocorr_sse2;
113 #endif
114 
116  c->lpc_apply_welch_window = ff_lpc_apply_welch_window_sse2;
117 
119  c->lpc_apply_welch_window = ff_lpc_apply_welch_window_avx2;
120 }
cpu.h
data
const char data[16]
Definition: mxf.c:148
av_get_cpu_flags
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:103
lpc.h
cpu_flags
static atomic_int cpu_flags
Definition: cpu.c:52
LPCContext
Definition: lpc.h:51
ff_lpc_init_x86
av_cold void ff_lpc_init_x86(LPCContext *c)
Definition: lpc_init.c:106
ff_lpc_apply_welch_window_sse2
void ff_lpc_apply_welch_window_sse2(const int32_t *data, ptrdiff_t len, double *w_data)
EXTERNAL_AVX2
#define EXTERNAL_AVX2(flags)
Definition: cpu.h:78
av_cold
#define av_cold
Definition: attributes.h:90
ff_lpc_apply_welch_window_avx2
void ff_lpc_apply_welch_window_avx2(const int32_t *data, ptrdiff_t len, double *w_data)
NAMED_CONSTRAINTS_ARRAY_ADD
#define NAMED_CONSTRAINTS_ARRAY_ADD(...)
Definition: asm.h:150
double
double
Definition: af_crystalizer.c:131
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
asm.h
attributes.h
EXTERNAL_SSE2
#define EXTERNAL_SSE2(flags)
Definition: cpu.h:59
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
DECLARE_ASM_CONST
DECLARE_ASM_CONST(16, double, pd_1)[2]
len
int len
Definition: vorbis_enc_data.h:426
__asm__
__asm__(".macro parse_r var r\n\t" "\\var = -1\n\t" _IFC_REG(0) _IFC_REG(1) _IFC_REG(2) _IFC_REG(3) _IFC_REG(4) _IFC_REG(5) _IFC_REG(6) _IFC_REG(7) _IFC_REG(8) _IFC_REG(9) _IFC_REG(10) _IFC_REG(11) _IFC_REG(12) _IFC_REG(13) _IFC_REG(14) _IFC_REG(15) _IFC_REG(16) _IFC_REG(17) _IFC_REG(18) _IFC_REG(19) _IFC_REG(20) _IFC_REG(21) _IFC_REG(22) _IFC_REG(23) _IFC_REG(24) _IFC_REG(25) _IFC_REG(26) _IFC_REG(27) _IFC_REG(28) _IFC_REG(29) _IFC_REG(30) _IFC_REG(31) ".iflt \\var\n\t" ".error \"Unable to parse register name \\r\"\n\t" ".endif\n\t" ".endm")
MANGLE
#define MANGLE(a)
Definition: asm.h:127
INLINE_SSE2_SLOW
#define INLINE_SSE2_SLOW(flags)
Definition: cpu.h:92
x86_reg
int x86_reg
Definition: asm.h:72
int32_t
int32_t
Definition: audioconvert.c:56