FFmpeg
fmtconvert_altivec.c
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1 /*
2  * Copyright (c) 2006 Luca Barbato <lu_zero@gentoo.org>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "config.h"
22 #include "libavutil/attributes.h"
23 #include "libavutil/cpu.h"
24 #include "libavutil/mem.h"
25 #include "libavutil/ppc/cpu.h"
27 #include "libavcodec/fmtconvert.h"
28 
29 #if HAVE_ALTIVEC
30 
31 static void int32_to_float_fmul_scalar_altivec(float *dst, const int32_t *src,
32  float mul, int len)
33 {
34  union {
35  vector float v;
36  float s[4];
37  } mul_u;
38  int i;
39  vector float src1, src2, dst1, dst2, mul_v, zero;
40 
41  zero = (vector float)vec_splat_u32(0);
42  mul_u.s[0] = mul;
43  mul_v = vec_splat(mul_u.v, 0);
44 
45  for (i = 0; i < len; i += 8) {
46  src1 = vec_ctf(vec_ld(0, src+i), 0);
47  src2 = vec_ctf(vec_ld(16, src+i), 0);
48  dst1 = vec_madd(src1, mul_v, zero);
49  dst2 = vec_madd(src2, mul_v, zero);
50  vec_st(dst1, 0, dst+i);
51  vec_st(dst2, 16, dst+i);
52  }
53 }
54 
55 #endif /* HAVE_ALTIVEC */
56 
58 {
59 #if HAVE_ALTIVEC
61  return;
62 
63  c->int32_to_float_fmul_scalar = int32_to_float_fmul_scalar_altivec;
64 #endif /* HAVE_ALTIVEC */
65 }
src1
const pixel * src1
Definition: h264pred_template.c:421
av_get_cpu_flags
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:103
fmtconvert.h
av_cold
#define av_cold
Definition: attributes.h:90
float
float
Definition: af_crystalizer.c:121
s
#define s(width, name)
Definition: cbs_vp9.c:198
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
ff_fmt_convert_init_ppc
av_cold void ff_fmt_convert_init_ppc(FmtConvertContext *c)
Definition: fmtconvert_altivec.c:57
PPC_ALTIVEC
#define PPC_ALTIVEC(flags)
Definition: cpu.h:25
cpu.h
attributes.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
src2
const pixel * src2
Definition: h264pred_template.c:422
len
int len
Definition: vorbis_enc_data.h:426
zero
#define zero
Definition: regdef.h:64
mem.h
util_altivec.h
FmtConvertContext
Definition: fmtconvert.h:28
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
cpu.h
int32_t
int32_t
Definition: audioconvert.c:56