1 /* Copyright (C) 2001 Erik de Castro Lopo <erikd AT mega-nerd DOT com> */
2 /*
3 Redistribution and use in source and binary forms, with or without
4 modification, are permitted provided that the following conditions
5 are met:
6
7 - Redistributions of source code must retain the above copyright
8 notice, this list of conditions and the following disclaimer.
9
10 - Redistributions in binary form must reproduce the above copyright
11 notice, this list of conditions and the following disclaimer in the
12 documentation and/or other materials provided with the distribution.
13
14 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
15 ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
16 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
17 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
18 OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
22 LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
23 NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
24 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 /* Version 1.1 */
28
29 #ifndef FLOAT_CAST_H
30 #define FLOAT_CAST_H
31
32
33 #include "arch.h"
34
35 /*============================================================================
36 ** On Intel Pentium processors (especially PIII and probably P4), converting
37 ** from float to int is very slow. To meet the C specs, the code produced by
38 ** most C compilers targeting Pentium needs to change the FPU rounding mode
39 ** before the float to int conversion is performed.
40 **
41 ** Changing the FPU rounding mode causes the FPU pipeline to be flushed. It
42 ** is this flushing of the pipeline which is so slow.
43 **
44 ** Fortunately the ISO C99 specifications define the functions lrint, lrintf,
45 ** llrint and llrintf which fix this problem as a side effect.
46 **
47 ** On Unix-like systems, the configure process should have detected the
48 ** presence of these functions. If they weren't found we have to replace them
49 ** here with a standard C cast.
50 */
51
52 /*
53 ** The C99 prototypes for lrint and lrintf are as follows:
54 **
55 ** long int lrintf (float x) ;
56 ** long int lrint (double x) ;
57 */
58
59 /* The presence of the required functions are detected during the configure
60 ** process and the values HAVE_LRINT and HAVE_LRINTF are set accordingly in
61 ** the config.h file.
62 */
63
64 /* With GCC, when SSE is available, the fastest conversion is cvtss2si. */
65 #if defined(__GNUC__) && defined(__SSE__)
66
67 #include <xmmintrin.h>
float2int(float x)68 static OPUS_INLINE opus_int32 float2int(float x) {return _mm_cvt_ss2si(_mm_set_ss(x));}
69
70 #elif defined(HAVE_LRINTF)
71
72 /* These defines enable functionality introduced with the 1999 ISO C
73 ** standard. They must be defined before the inclusion of math.h to
74 ** engage them. If optimisation is enabled, these functions will be
75 ** inlined. With optimisation switched off, you have to link in the
76 ** maths library using -lm.
77 */
78
79 #define _ISOC9X_SOURCE 1
80 #define _ISOC99_SOURCE 1
81
82 #define __USE_ISOC9X 1
83 #define __USE_ISOC99 1
84
85 #include <math.h>
86 #define float2int(x) lrintf(x)
87
88 #elif (defined(HAVE_LRINT))
89
90 #define _ISOC9X_SOURCE 1
91 #define _ISOC99_SOURCE 1
92
93 #define __USE_ISOC9X 1
94 #define __USE_ISOC99 1
95
96 #include <math.h>
97 #define float2int(x) lrint(x)
98
99 #elif (defined(_MSC_VER) && _MSC_VER >= 1400) && (defined(_M_X64) || (defined(_M_IX86_FP) && _M_IX86_FP >= 1))
100 #include <xmmintrin.h>
101
float2int(float value)102 __inline long int float2int(float value)
103 {
104 return _mm_cvtss_si32(_mm_load_ss(&value));
105 }
106 #elif (defined(_MSC_VER) && _MSC_VER >= 1400) && defined (_M_IX86)
107 #include <math.h>
108
109 /* Win32 doesn't seem to have these functions.
110 ** Therefore implement OPUS_INLINE versions of these functions here.
111 */
112
113 __inline long int
float2int(float flt)114 float2int (float flt)
115 { int intgr;
116
117 _asm
118 { fld flt
119 fistp intgr
120 } ;
121
122 return intgr ;
123 }
124
125 #else
126
127 #if (defined(__GNUC__) && defined(__STDC__) && __STDC__ && __STDC_VERSION__ >= 199901L)
128 /* supported by gcc in C99 mode, but not by all other compilers */
129 #warning "Don't have the functions lrint() and lrintf ()."
130 #warning "Replacing these functions with a standard C cast."
131 #endif /* __STDC_VERSION__ >= 199901L */
132 #include <math.h>
133 #define float2int(flt) ((int)(floor(.5+flt)))
134 #endif
135
136 #ifndef DISABLE_FLOAT_API
FLOAT2INT16(float x)137 static OPUS_INLINE opus_int16 FLOAT2INT16(float x)
138 {
139 x = x*CELT_SIG_SCALE;
140 x = MAX32(x, -32768);
141 x = MIN32(x, 32767);
142 return (opus_int16)float2int(x);
143 }
144 #endif /* DISABLE_FLOAT_API */
145
146 #endif /* FLOAT_CAST_H */
147