/[svn]/linuxsampler/trunk/src/common/RTMath.h
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Thu Dec 15 12:47:45 2016 UTC (7 years, 5 months ago) by schoenebeck
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* Fixed numerous compiler warnings.
* Bumped version (2.0.0.svn32).

1 schoenebeck 53 /***************************************************************************
2     * *
3     * LinuxSampler - modular, streaming capable sampler *
4     * *
5 schoenebeck 56 * Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck *
6 schoenebeck 2931 * Copyright (C) 2005 - 2016 Christian Schoenebeck *
7 schoenebeck 53 * *
8     * This program is free software; you can redistribute it and/or modify *
9     * it under the terms of the GNU General Public License as published by *
10     * the Free Software Foundation; either version 2 of the License, or *
11     * (at your option) any later version. *
12     * *
13     * This program is distributed in the hope that it will be useful, *
14     * but WITHOUT ANY WARRANTY; without even the implied warranty of *
15     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
16     * GNU General Public License for more details. *
17     * *
18     * You should have received a copy of the GNU General Public License *
19     * along with this program; if not, write to the Free Software *
20     * Foundation, Inc., 59 Temple Place, Suite 330, Boston, *
21     * MA 02111-1307 USA *
22     ***************************************************************************/
23    
24     #ifndef __RT_MATH_H__
25     #define __RT_MATH_H__
26    
27     #include <math.h>
28 schoenebeck 328 #include <stdint.h>
29 schoenebeck 1424 #include "global_private.h"
30 schoenebeck 53
31     /// Needed for calculating frequency ratio used to pitch a sample
32     #define TWELVEHUNDREDTH_ROOT_OF_TWO 1.000577789506555
33    
34 schoenebeck 319 enum implementation_t {
35 schoenebeck 361 CPP,
36     ASM_X86_MMX_SSE
37 schoenebeck 319 };
38    
39 schoenebeck 563 /** @brief Real Time Math Base Class
40     *
41     * Math functions for real time operation. This base class contains all
42     * non-template methods.
43     */
44 schoenebeck 319 class RTMathBase {
45 schoenebeck 53 public:
46     /**
47 schoenebeck 2942 * High resolution time stamp.
48 schoenebeck 328 */
49     typedef uint32_t time_stamp_t;
50    
51 schoenebeck 2942 typedef uint64_t usecs_t;
52    
53 schoenebeck 328 /**
54     * We read the processor's cycle count register as a reference
55     * for the real time. These are of course only abstract values
56     * with arbitrary time entity, but that's not a problem as long
57     * as we calculate relatively.
58 schoenebeck 2942 *
59     * @see unsafeMicroSeconds()
60 schoenebeck 328 */
61     static time_stamp_t CreateTimeStamp();
62    
63     /**
64 schoenebeck 53 * Calculates the frequency ratio for a pitch value given in cents
65     * (assuming equal tempered scale of course, divided into 12
66     * semitones per octave and 100 cents per semitone).
67     *
68 schoenebeck 554 * Note: CONFIG_MAX_PITCH (defined in config.h) has to be defined to an
69 schoenebeck 53 * appropriate value, otherwise the behavior of this function is
70 schoenebeck 554 * undefined, but most probably if CONFIG_MAX_PITCH is too small, the
71 schoenebeck 53 * application will crash due to segmentation fault here.
72     *
73     * @param cents - pitch value in cents (+1200 cents means +1 octave)
74     * @returns frequency ratio (e.g. +2.0 for +1 octave)
75     */
76     inline static double CentsToFreqRatio(double Cents) {
77 schoenebeck 319 int index_int = (int) (Cents); // integer index
78 schoenebeck 53 float index_fract = Cents - index_int; // fractional part of index
79     return pCentsToFreqTable[index_int] + index_fract * (pCentsToFreqTable[index_int+1] - pCentsToFreqTable[index_int]);
80     }
81    
82 schoenebeck 829 /**
83 persson 1862 * Slower version of CentsToFreqRatio, for big values.
84     *
85     * @param cents - pitch value in cents (+1200 cents means +1 octave)
86     * @returns frequency ratio (e.g. +2.0 for +1 octave)
87     */
88     static double CentsToFreqRatioUnlimited(double Cents) {
89     int octaves = int(Cents / 1200);
90     double x = CentsToFreqRatio(Cents - octaves * 1200);
91     return octaves < 0 ? x / (1 << -octaves) : x * (1 << octaves);
92     }
93    
94     /**
95 schoenebeck 829 * Inverse function to CentsToFreqRatio(). This function is a bit
96     * slow, so it should not be called too frequently.
97     */
98     static double FreqRatioToCents(double FreqRatio) {
99     return log(FreqRatio) / log(TWELVEHUNDREDTH_ROOT_OF_TWO);
100     }
101    
102 schoenebeck 2931 /**
103     * Calculates the line ratio value representation (linear scale)
104     * of the @a decibel value provided (exponential scale).
105     *
106     * The context of audio acoustic sound pressure levels is assumed, and
107     * hence the field version of the dB unit is used here (which uses a
108     * linear factor of 20). This function is a bit slow, so it should
109     * not be called too frequently.
110     *
111     * @param decibel - sound pressure level in dB
112     * @returns linear ratio of the supplied dB value
113     */
114     static float DecibelToLinRatio(float decibel) {
115     return powf(10.f, decibel / 20.f);
116     }
117    
118     /**
119     * Calculates the relatively summed average of a set of values.
120     *
121     * @param current - the current avaerage value of all previously summed values
122     * @param sample - new value to be applied as summed average to the existing values
123     * @param n - amount of sample values applied so far
124     * @returns new average value of all summed values (including the new @a sample)
125     */
126 schoenebeck 3054 template<typename T_int>
127     inline static float RelativeSummedAvg(float current, float sample, T_int n) {
128 schoenebeck 2931 return current + (sample - current) / float(n);
129     }
130    
131 schoenebeck 2942 /**
132     * Clock source to use for getting the current time.
133     */
134     enum clock_source_t {
135     real_clock, ///< Use this to measure time that passed in reality (no matter if process got suspended).
136     process_clock, ///< Use this to measure only the CPU execution time of the current process (if the process got suspended, the clock is paused as well).
137     thread_clock, ///< Use this to measure only the CPU execution time of the current thread (if the process got suspended or another thread is executed, the clock is paused as well).
138     };
139    
140     /**
141     * Returns a time stamp of the current time in microseconds (in
142     * probably real-time @b unsafe way). There is no guarantee about
143     * what the returned amount of microseconds relates to (i.e.
144     * microseconds since epoch, microseconds since system uptime, ...).
145     * So you should only use it to calculate time differences between
146     * values taken with this method.
147     *
148     * @b CAUTION: This method may not @b NOT be real-time safe! On some
149     * systems it could be RT safe, but there is no guarantee whatsoever!
150     * So this method should only be used for debugging, benchmarking and
151     * other developing purposes !
152     *
153     * For creating time stamps in real-time context, use
154     * CreateTimeStamp() instead.
155     *
156     * @param source - the actual clock to use for getting the current
157     * time, note that the various clock sources may not
158     * be implemented on all systems
159     * @returns time stamp in microseconds
160     *
161     * @see CreateTimeStamp()
162     */
163     static usecs_t unsafeMicroSeconds(clock_source_t source);
164    
165 schoenebeck 319 private:
166     static float* pCentsToFreqTable;
167    
168     static float* InitCentsToFreqTable();
169     };
170    
171 schoenebeck 563 /** @brief Real Time Math
172 schoenebeck 319 *
173 schoenebeck 563 * This is a template which provides customized methods for the desired low
174     * level implementation. The ASM_X86_MMX_SSE implementation of each method
175     * for example doesn't use 387 FPU instruction. This is needed for MMX
176     * algorithms which do not allow mixed MMX and 387 instructions.
177 schoenebeck 319 */
178     template<implementation_t IMPL = CPP>
179     class __RTMath : public RTMathBase {
180     public:
181     // conversion using truncate
182     inline static int Int(const float a) {
183     switch (IMPL) {
184 schoenebeck 617 #if CONFIG_ASM && ARCH_X86
185 schoenebeck 319 case ASM_X86_MMX_SSE: {
186     int ret;
187     asm (
188     "cvttss2si %1, %0 # convert to int\n\t"
189     : "=r" (ret)
190     : "m" (a)
191     );
192     return ret;
193     }
194 schoenebeck 617 #endif // CONFIG_ASM && ARCH_X86
195 persson 685 default: {
196     return (int) a;
197     }
198 schoenebeck 319 }
199     }
200    
201     //for doubles and everything else except floats
202     template<class T_a> inline static int Int(const T_a a) {
203     return (int) a;
204     }
205    
206     inline static float Float(const int a) {
207     switch (IMPL) {
208 schoenebeck 617 #if CONFIG_ASM && ARCH_X86
209 schoenebeck 319 case ASM_X86_MMX_SSE: {
210     float ret;
211     asm (
212     "cvtsi2ss %1, %%xmm0 # convert to float\n\t"
213     "movss %%xmm0,%0 # output\n\t"
214     : "=m" (ret)
215     : "r" (a)
216     );
217     return ret;
218     }
219 schoenebeck 617 #endif // CONFIG_ASM && ARCH_X86
220 persson 685 default: {
221     return (float) a;
222     }
223 schoenebeck 319 }
224     }
225    
226     #if 0
227     //for everything except ints
228     template<class T_a> inline static float Float(T_a a) {
229     return (float) a;
230     }
231     #endif
232    
233     inline static float Sum(const float& a, const float& b) {
234     switch (IMPL) {
235 schoenebeck 617 #if CONFIG_ASM && ARCH_X86
236 schoenebeck 319 case ASM_X86_MMX_SSE: {
237     float ret;
238     asm (
239     "movss %1, %%xmm0 # load a\n\t"
240     "addss %2, %%xmm0 # a + b\n\t"
241     "movss %%xmm0, %0 # output\n\t"
242     : "=m" (ret)
243     : "m" (a), "m" (b)
244     );
245     return ret;
246     }
247 schoenebeck 617 #endif // CONFIG_ASM && ARCH_X86
248 persson 685 default: {
249     return (a + b);
250     }
251 schoenebeck 319 }
252     }
253    
254     template<class T_a, class T_b> inline static T_a Sum(const T_a a, const T_b b) {
255     return (a + b);
256     }
257    
258     inline static float Sub(const float& a, const float& b) {
259     switch (IMPL) {
260 schoenebeck 617 #if CONFIG_ASM && ARCH_X86
261 schoenebeck 319 case ASM_X86_MMX_SSE: {
262     float ret;
263     asm (
264     "movss %1, %%xmm0 # load a\n\t"
265     "subss %2, %%xmm0 # a - b\n\t"
266     "movss %%xmm0, %0 # output\n\t"
267     : "=m" (ret)
268     : "m" (a), "m" (b)
269     );
270     return ret;
271     }
272 schoenebeck 617 #endif // CONFIG_ASM && ARCH_X86
273 persson 685 default: {
274     return (a - b);
275     }
276 schoenebeck 319 }
277     }
278    
279     template<class T_a, class T_b> inline static T_a Sub(const T_a a, const T_b b) {
280     return (a - b);
281     }
282    
283     inline static float Mul(const float a, const float b) {
284     switch (IMPL) {
285 schoenebeck 617 #if CONFIG_ASM && ARCH_X86
286 schoenebeck 319 case ASM_X86_MMX_SSE: {
287     float ret;
288     asm (
289     "movss %1, %%xmm0 # load a\n\t"
290     "mulss %2, %%xmm0 # a * b\n\t"
291     "movss %%xmm0, %0 # output\n\t"
292     : "=m" (ret)
293     : "m" (a), "m" (b)
294     );
295     return ret;
296     }
297 schoenebeck 617 #endif // CONFIG_ASM && ARCH_X86
298 persson 685 default: {
299     return (a * b);
300     }
301 schoenebeck 319 }
302     }
303    
304     template<class T_a, class T_b> inline static T_a Mul(const T_a a, const T_b b) {
305     return (a * b);
306     }
307    
308     inline static float Div(const float a, const float b) {
309     switch (IMPL) {
310 schoenebeck 617 #if CONFIG_ASM && ARCH_X86
311 schoenebeck 319 case ASM_X86_MMX_SSE: {
312     float ret;
313     asm (
314     "movss %1, %%xmm0 # load a\n\t"
315     "divss %2, %%xmm0 # a / b\n\t"
316     "movss %%xmm0, %0 # output\n\t"
317     : "=m" (ret)
318     : "m" (a), "m" (b)
319     );
320     return ret;
321     }
322 schoenebeck 617 #endif // CONFIG_ASM && ARCH_X86
323 persson 685 default: {
324     return (a / b);
325     }
326 schoenebeck 319 }
327     }
328    
329     template<class T_a, class T_b> inline static T_a Div(const T_a a, const T_b b) {
330     return (a / b);
331     }
332    
333     inline static float Min(const float a, const float b) {
334     switch (IMPL) {
335 schoenebeck 617 #if CONFIG_ASM && ARCH_X86
336 schoenebeck 319 case ASM_X86_MMX_SSE: {
337     float ret;
338     asm (
339     "movss %1, %%xmm0 # load a\n\t"
340     "minss %2, %%xmm0 # Minimum(a, b)\n\t"
341     "movss %%xmm0, %0 # output\n\t"
342     : "=m" (ret)
343     : "m" (a), "m" (b)
344     );
345     return ret;
346     }
347 schoenebeck 617 #endif // CONFIG_ASM && ARCH_X86
348 persson 685 default: {
349 wylder 818 return std::min(a, b);
350 persson 685 }
351 schoenebeck 319 }
352     }
353    
354     template<class T_a, class T_b> inline static T_a Min(const T_a a, const T_b b) {
355 schoenebeck 53 return (b < a) ? b : a;
356     }
357    
358 schoenebeck 319 inline static float Max(const float a, const float b) {
359     switch (IMPL) {
360 schoenebeck 617 #if CONFIG_ASM && ARCH_X86
361 schoenebeck 319 case ASM_X86_MMX_SSE: {
362     float ret;
363     asm (
364     "movss %1, %%xmm0 # load a\n\t"
365     "maxss %2, %%xmm0 # Maximum(a, b)\n\t"
366     "movss %%xmm0, %0 # output\n\t"
367     : "=m" (ret)
368     : "m" (a), "m" (b)
369     );
370     return ret;
371     }
372 schoenebeck 617 #endif // CONFIG_ASM && ARCH_X86
373 persson 685 default: {
374 wylder 818 return std::max(a, b);
375 persson 685 }
376 schoenebeck 319 }
377     }
378    
379     template<class T_a, class T_b> inline static T_a Max(const T_a a, const T_b b) {
380 schoenebeck 53 return (b > a) ? b : a;
381     }
382    
383 schoenebeck 319 inline static float Fmodf(const float &a, const float &b) {
384     switch (IMPL) {
385 schoenebeck 617 #if CONFIG_ASM && ARCH_X86
386 schoenebeck 319 case ASM_X86_MMX_SSE: {
387     float ret;
388     asm (
389     "movss %1, %%xmm0 # load a\n\t"
390     "movss %2, %%xmm1 # load b\n\t"
391     "movss %%xmm0,%%xmm2\n\t"
392     "divss %%xmm1, %%xmm2 # xmm2 = a / b\n\t"
393     "cvttss2si %%xmm2, %%ecx #convert to int\n\t"
394     "cvtsi2ss %%ecx, %%xmm2 #convert back to float\n\t"
395     "mulss %%xmm1, %%xmm2 # xmm2 = b * int(a/b)\n\t"
396     "subss %%xmm2, %%xmm0 #sub a\n\t"
397     "movss %%xmm0, %0 # output\n\t"
398     : "=m" (ret)
399     : "m" (a), "m" (b)
400     : "%ecx"
401     );
402     return ret;
403     }
404 schoenebeck 617 #endif // CONFIG_ASM && ARCH_X86
405 persson 685 default: {
406     return fmodf(a, b);
407     }
408 schoenebeck 319 }
409     }
410 schoenebeck 53 };
411    
412 schoenebeck 319 /// convenience typedef for using the default implementation (which is CPP)
413     typedef __RTMath<> RTMath;
414    
415 schoenebeck 53 #endif // __RT_MATH_H__

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