1 #ifndef _OS_H
2 #define _OS_H
3 /********************************************************************
4  *                                                                  *
5  * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
6  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
7  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
8  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
9  *                                                                  *
10  * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009             *
11  * by the Xiph.Org Foundation http://www.xiph.org/                  *
12  *                                                                  *
13  ********************************************************************
14 
15  function: #ifdef jail to whip a few platforms into the UNIX ideal.
16  last mod: $Id: os.h 16227 2009-07-08 06:58:46Z xiphmont $
17 
18  ********************************************************************/
19 
20 #ifdef HAVE_CONFIG_H
21 #include "config.h"
22 #endif
23 
24 #include <math.h>
25 #include <ogg/os_types.h>
26 
27 #include "misc.h"
28 
29 #ifndef _V_IFDEFJAIL_H_
30 #  define _V_IFDEFJAIL_H_
31 
32 #  ifdef __GNUC__
33 #    define STIN static __inline__
34 #  elif _WIN32
35 #    define STIN static __inline
36 #  else
37 #    define STIN static
38 #  endif
39 
40 #ifdef DJGPP
41 #  define rint(x)   (floor((x)+0.5f))
42 #endif
43 
44 #ifndef M_PI
45 #  define M_PI (3.1415926536f)
46 #endif
47 
48 #if defined(_WIN32) && !defined(__SYMBIAN32__)
49 #  include <malloc.h>
50 #  define rint(x)   (floor((x)+0.5f))
51 #  define NO_FLOAT_MATH_LIB
52 #  define FAST_HYPOT(a, b) sqrt((a)*(a) + (b)*(b))
53 #endif
54 
55 #if defined(__SYMBIAN32__) && defined(__WINS__)
56 void *_alloca(size_t size);
57 #  define alloca _alloca
58 #endif
59 
60 #ifndef FAST_HYPOT
61 #  define FAST_HYPOT hypot
62 #endif
63 
64 #endif
65 
66 #ifdef HAVE_ALLOCA_H
67 #  include <alloca.h>
68 #endif
69 
70 #ifdef USE_MEMORY_H
71 #  include <memory.h>
72 #endif
73 
74 #ifndef min
75 #  define min(x,y)  ((x)>(y)?(y):(x))
76 #endif
77 
78 #ifndef max
79 #  define max(x,y)  ((x)<(y)?(y):(x))
80 #endif
81 
82 
83 /* Special i386 GCC implementation */
84 #if defined(__i386__) && defined(__GNUC__) && !defined(__BEOS__)
85 #  define VORBIS_FPU_CONTROL
86 /* both GCC and MSVC are kinda stupid about rounding/casting to int.
87    Because of encapsulation constraints (GCC can't see inside the asm
88    block and so we end up doing stupid things like a store/load that
89    is collectively a noop), we do it this way */
90 
91 /* we must set up the fpu before this works!! */
92 
93 typedef ogg_int16_t vorbis_fpu_control;
94 
vorbis_fpu_setround(vorbis_fpu_control * fpu)95 static inline void vorbis_fpu_setround(vorbis_fpu_control *fpu){
96   ogg_int16_t ret;
97   ogg_int16_t temp;
98   __asm__ __volatile__("fnstcw %0\n\t"
99           "movw %0,%%dx\n\t"
100           "andw $62463,%%dx\n\t"
101           "movw %%dx,%1\n\t"
102           "fldcw %1\n\t":"=m"(ret):"m"(temp): "dx");
103   *fpu=ret;
104 }
105 
vorbis_fpu_restore(vorbis_fpu_control fpu)106 static inline void vorbis_fpu_restore(vorbis_fpu_control fpu){
107   __asm__ __volatile__("fldcw %0":: "m"(fpu));
108 }
109 
110 /* assumes the FPU is in round mode! */
vorbis_ftoi(double f)111 static inline int vorbis_ftoi(double f){  /* yes, double!  Otherwise,
112                                              we get extra fst/fld to
113                                              truncate precision */
114   int i;
115   __asm__("fistl %0": "=m"(i) : "t"(f));
116   return(i);
117 }
118 #endif /* Special i386 GCC implementation */
119 
120 
121 /* MSVC inline assembly. 32 bit only; inline ASM isn't implemented in the
122  * 64 bit compiler */
123 #if defined(_MSC_VER) && !defined(_WIN64) && !defined(_WIN32_WCE)
124 #  define VORBIS_FPU_CONTROL
125 
126 typedef ogg_int16_t vorbis_fpu_control;
127 
vorbis_ftoi(double f)128 static __inline int vorbis_ftoi(double f){
129         int i;
130         __asm{
131                 fld f
132                 fistp i
133         }
134         return i;
135 }
136 
vorbis_fpu_setround(vorbis_fpu_control * fpu)137 static __inline void vorbis_fpu_setround(vorbis_fpu_control *fpu){
138 }
139 
vorbis_fpu_restore(vorbis_fpu_control fpu)140 static __inline void vorbis_fpu_restore(vorbis_fpu_control fpu){
141 }
142 
143 #endif /* Special MSVC 32 bit implementation */
144 
145 
146 /* Optimized code path for x86_64 builds. Uses SSE2 intrinsics. This can be
147    done safely because all x86_64 CPUs supports SSE2. */
148 #if (defined(_MSC_VER) && defined(_WIN64)) || (defined(__GNUC__) && defined (__x86_64__))
149 #  define VORBIS_FPU_CONTROL
150 
151 typedef ogg_int16_t vorbis_fpu_control;
152 
153 #include <emmintrin.h>
vorbis_ftoi(double f)154 static __inline int vorbis_ftoi(double f){
155         return _mm_cvtsd_si32(_mm_load_sd(&f));
156 }
157 
vorbis_fpu_setround(vorbis_fpu_control * fpu)158 static __inline void vorbis_fpu_setround(vorbis_fpu_control *fpu){
159 }
160 
vorbis_fpu_restore(vorbis_fpu_control fpu)161 static __inline void vorbis_fpu_restore(vorbis_fpu_control fpu){
162 }
163 
164 #endif /* Special MSVC x64 implementation */
165 
166 
167 /* If no special implementation was found for the current compiler / platform,
168    use the default implementation here: */
169 #ifndef VORBIS_FPU_CONTROL
170 
171 typedef int vorbis_fpu_control;
172 
vorbis_ftoi(double f)173 static int vorbis_ftoi(double f){
174         /* Note: MSVC and GCC (at least on some systems) round towards zero, thus,
175            the floor() call is required to ensure correct roudning of
176            negative numbers */
177         return (int)floor(f+.5);
178 }
179 
180 /* We don't have special code for this compiler/arch, so do it the slow way */
181 #  define vorbis_fpu_setround(vorbis_fpu_control) {}
182 #  define vorbis_fpu_restore(vorbis_fpu_control) {}
183 
184 #endif /* default implementation */
185 
186 #endif /* _OS_H */
187