trunk/benchmarks/triang.cpp

/*
    Triangle wave generator benchmark

    This is a benchmark for comparison between a integer math, table lookup
    and numeric sine wave harmonics solution.

    Copyright (C) 2005 Christian Schoenebeck <cuse@users.sf.net>
*/

#include <math.h>
#include <time.h>
#include <stdio.h>

// whether we should not show any messages on the console
#ifndef SILENT
# define SILENT 0
#endif

// set to 1 if you want to output the three calculated waves as RAW files
// you can e.g. open it as RAW file in Rezound
// (32 bit SP-FP PCM, mono, little endian, 44100kHz)
#ifndef OUTPUT_AS_RAW_WAVE
# define OUTPUT_AS_RAW_WAVE     0
#endif

// how many sample points should we calculate in one sequence
#ifndef STEPS
# define STEPS                  16384
#endif

// how often should we repeat the benchmark loop of each solution
#ifndef RUNS
# define RUNS                   1000
#endif

// whether the wave should have positive and negative range (signed -> 1) or just positive (unsigned -> 0)
#ifndef SIGNED
# define SIGNED                 1
#endif

// pro forma
#ifndef SAMPLING_RATE
# define SAMPLING_RATE          44100.0f
#endif

// return value of this benchmark
// to indicate the best performing solution
#define INT_MATH_SOLUTION       2  /* we don't start with 1, as this is reserved for unknown errors */
#define DI_HARMONIC_SOLUTION    3
#define TABLE_LOOKUP_SOLUTION   4  /* table lookup solution is currently disabled in this benchmark, see below */
#define INVALID_RESULT          -1

// we use 32 bit single precision floating point as sample point format
typedef float sample_t;

// integer math solution
float int_math(sample_t* pDestinationBuffer, float* pAmp, const int steps, const float frequency) {
    // pro forma
    const float r = frequency / SAMPLING_RATE; // frequency alteration quotient
    unsigned int maxvalue = (unsigned int) -1; // all 0xFFFF...
    #if SIGNED
    const float normalizer = 1.0f / ((float) maxvalue / 4.0f);
    #else // unsigned
    const float normalizer = 1.0f / ((float) maxvalue / 2.0f);
    #endif
    const int c = (int) (maxvalue * r);
    const int signshifts = (sizeof(int) * 8) - 1;

    int iSign;

    clock_t stop_time;
    clock_t start_time = clock();

    for (int run = 0; run < RUNS; run++) {
        int iLevel = 0;
        for (int i = 0; i < steps; ++i) {
            iLevel += c;
            iSign  = (iLevel >> signshifts) | 1;
            #if SIGNED
            pDestinationBuffer[i] = (normalizer * (float) (iSign * iLevel) - 1.0f) * pAmp[i]; // * pAmp[i] just to simulate some memory load
            #else // unsigned
            pDestinationBuffer[i] = normalizer * (float) (iSign * iLevel) * pAmp[i]; // * pAmp[i] just to simulate some memory load
            #endif
        }
    }

    stop_time = clock();
    float elapsed_time = (stop_time - start_time) / (double(CLOCKS_PER_SEC) / 1000.0);
    #if ! SILENT
    printf("int math solution elapsed time: %1.0f ms\n", elapsed_time);
    #endif

    return elapsed_time;
}

// table lookup solution (currently disabled)
//
// This solution is not yet implemented in LinuxSampler yet and probably
// never will, I simply haven't found an architectures / system where this
// turned out to be the best solution and it introduces too many problems
// anyway. If you found an architecture where this seems to be the best
// solution, please let us know!
#if 0
float table_lookup(sample_t* pDestinationBuffer, float* pAmp, const int steps, const float frequency) {
    // pro forma
    const float r = frequency / SAMPLING_RATE; // frequency alteration quotient
    #if SIGNED
    float c = r * 4.0f;
    #else
    float c = r * 2.0f;
    #endif
    const int wl = (int) (SAMPLING_RATE / frequency); // wave length (in sample points)

    // 'volatile' to avoid the cache to fudge the benchmark result
    volatile float* pPrerenderingBuffer = new float[wl];

    // prerendering of the triangular wave
    {
        float level = 0.0f;
        for (int i = 0; i < wl; ++i) {
            level += c;
            #if SIGNED
            if (level >= 1.0f) {
                c = -c;
                level = 1.0f;
            }
            else if (level <= -1.0f) {
                c = -c;
                level = -1.0f;
            }
            #else
            if (level >= 1.0f) {
                c = -c;
                level = 1.0f;
            }
            else if (level <= 0.0f) {
                c = -c;
                level = 0.0f;
            }
            #endif
            pPrerenderingBuffer[i] = level;
        }
    }

    clock_t stop_time;
    clock_t start_time = clock();

    for (int run = 0; run < RUNS; run++) {
        for (int i = 0; i < steps; ++i) {
            pDestinationBuffer[i] = pPrerenderingBuffer[i % wl] * pAmp[i]; // * pAmp[i] just to simulate some memory load
        }
    }

    stop_time = clock();
    float elapsed_time = (stop_time - start_time) / (double(CLOCKS_PER_SEC) / 1000.0);
    #if ! SILENT
    printf("Table lookup solution elapsed time: %1.0f ms\n", elapsed_time);
    #endif

    if (pPrerenderingBuffer) delete[] pPrerenderingBuffer;

    return elapsed_time;
}
#endif

// numeric, di-harmonic solution
float numeric_di_harmonic_solution(sample_t* pDestinationBuffer, float* pAmp, const int steps, const float frequency) {
    // we approximate the triangular wave by adding 2 harmonics
    const float c1   = 2.0f * M_PI * frequency / SAMPLING_RATE;
    const float phi1 = 0.0f; // phase displacement
    const float c2   = 2.0f * M_PI * frequency / SAMPLING_RATE * 3.0f;
    const float phi2 = 0.0f; // phase displacement

    // amplitue for the 2nd harmonic (to approximate the triangular wave)
    const float amp2 = 0.1f;

    // initial values for real and imaginary part
    float real1 = cos(phi1);
    float imag1 = sin(phi1);
    float real2 = cos(phi2);
    float imag2 = sin(phi2);

    clock_t stop_time;
    clock_t start_time = clock();

    for (int run = 0; run < RUNS; run++) {
        for (int i = 0; i < steps; i++) {
            #if SIGNED
            pDestinationBuffer[i] = (real1 + real2 * amp2) * pAmp[i]; // * pAmp[i] just to simulate some memory load
            #else // unsigned
            pDestinationBuffer[i] = ((real1 + real2 * amp2) * 0.5f + 0.5f) * pAmp[i]; // * pAmp[i] just to simulate some memory load
            #endif
            real1 -= c1 * imag1;
            imag1 += c1 * real1;
            real2 -= c2 * imag2;
            imag2 += c2 * real2;
        }
    }

    stop_time = clock();
    float elapsed_time = (stop_time - start_time) / (double(CLOCKS_PER_SEC) / 1000.0);
    #if ! SILENT
    printf("Numeric harmonics solution elapsed time: %1.0f ms\n", elapsed_time);
    #endif

    return elapsed_time;
}

// output calculated values as RAW audio format (32 bit floating point, mono) file
void output_as_raw_file(const char* filename, sample_t* pOutputBuffer, int steps) {
    FILE* file = fopen(filename, "w");
    if (file) {
        fwrite((void*) pOutputBuffer, sizeof(float), steps, file);
        fclose(file);
    } else {
        fprintf(stderr, "Could not open %s\n", filename);
    }
}

int main() {
    const int steps = STEPS;
    const int sinusoidFrequency = 100; // Hz

    #if ! SILENT
    # if SIGNED
    printf("Signed triangular wave benchmark\n");
    printf("--------------------------------\n");
    # else
    printf("Unsigned triangular wave benchmark\n");
    printf("----------------------------------\n");
    # endif
    #endif

    // output buffer for the calculated sinusoid wave
    sample_t* pOutputBuffer = new sample_t[steps];
    // just an arbitrary amplitude envelope to simulate a bit higher memory bandwidth
    float* pAmplitude  = new float[steps];

    // pro forma - an arbitary amplitude envelope
    for (int i = 0; i < steps; ++i)
        pAmplitude[i] = (float) i / (float) steps;

    // how long each solution took (in seconds)
    float int_math_result, /*table_lookup_result,*/ numeric_di_harmonic_result;

    int_math_result = int_math(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);
    #if OUTPUT_AS_RAW_WAVE
      output_as_raw_file("bench_int_math.raw", pOutputBuffer, steps);
    #endif
    //table_lookup_result = table_lookup(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);
    //#if OUTPUT_AS_RAW_WAVE
    //  output_as_raw_file("bench_table_lookup.raw", pOutputBuffer, steps);
    //#endif
    numeric_di_harmonic_result = numeric_di_harmonic_solution(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);
    #if OUTPUT_AS_RAW_WAVE
      output_as_raw_file("bench_numeric_harmonics.raw", pOutputBuffer, steps);
    #endif

    #if ! SILENT
    printf("\nOK, 2nd try\n\n");
    #endif

    int_math_result            += int_math(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);
    //table_lookup_result        += table_lookup(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);
    numeric_di_harmonic_result += numeric_di_harmonic_solution(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);

    if (pAmplitude)    delete[] pAmplitude;
    if (pOutputBuffer) delete[] pOutputBuffer;

    if (/*int_math_result <= table_lookup_result &&*/ int_math_result <= numeric_di_harmonic_result) return INT_MATH_SOLUTION;
    if (/*numeric_di_harmonic_result <= table_lookup_result &&*/ numeric_di_harmonic_result <= int_math_result) return DI_HARMONIC_SOLUTION;
    //if (table_lookup_result <= int_math_result && table_lookup_result <= numeric_di_harmonic_result) return TABLE_LOOKUP_SOLUTION;

    return INVALID_RESULT; // error
}
1	/*
2	Triangle wave generator benchmark
3
4	This is a benchmark for comparison between a integer math, table lookup
5	and numeric sine wave harmonics solution.
6
7	Copyright (C) 2005 Christian Schoenebeck <cuse@users.sf.net>
8	*/
9
10	#include <math.h>
11	#include <time.h>
12	#include <stdio.h>
13
14	// whether we should not show any messages on the console
15	#ifndef SILENT
16	# define SILENT 0
17	#endif
18
19	// set to 1 if you want to output the three calculated waves as RAW files
20	// you can e.g. open it as RAW file in Rezound
21	// (32 bit SP-FP PCM, mono, little endian, 44100kHz)
22	#ifndef OUTPUT_AS_RAW_WAVE
23	# define OUTPUT_AS_RAW_WAVE 0
24	#endif
25
26	// how many sample points should we calculate in one sequence
27	#ifndef STEPS
28	# define STEPS 16384
29	#endif
30
31	// how often should we repeat the benchmark loop of each solution
32	#ifndef RUNS
33	# define RUNS 1000
34	#endif
35
36	// whether the wave should have positive and negative range (signed -> 1) or just positive (unsigned -> 0)
37	#ifndef SIGNED
38	# define SIGNED 1
39	#endif
40
41	// pro forma
42	#ifndef SAMPLING_RATE
43	# define SAMPLING_RATE 44100.0f
44	#endif
45
46	// return value of this benchmark
47	// to indicate the best performing solution
48	#define INT_MATH_SOLUTION 2 /* we don't start with 1, as this is reserved for unknown errors */
49	#define DI_HARMONIC_SOLUTION 3
50	#define TABLE_LOOKUP_SOLUTION 4 /* table lookup solution is currently disabled in this benchmark, see below */
51	#define INVALID_RESULT -1
52
53	// we use 32 bit single precision floating point as sample point format
54	typedef float sample_t;
55
56	// integer math solution
57	float int_math(sample_t* pDestinationBuffer, float* pAmp, const int steps, const float frequency) {
58	// pro forma
59	const float r = frequency / SAMPLING_RATE; // frequency alteration quotient
60	unsigned int maxvalue = (unsigned int) -1; // all 0xFFFF...
61	#if SIGNED
62	const float normalizer = 1.0f / ((float) maxvalue / 4.0f);
63	#else // unsigned
64	const float normalizer = 1.0f / ((float) maxvalue / 2.0f);
65	#endif
66	const int c = (int) (maxvalue * r);
67	const int signshifts = (sizeof(int) * 8) - 1;
68
69	int iSign;
70
71	clock_t stop_time;
72	clock_t start_time = clock();
73
74	for (int run = 0; run < RUNS; run++) {
75	int iLevel = 0;
76	for (int i = 0; i < steps; ++i) {
77	iLevel += c;
78	iSign = (iLevel >> signshifts) \| 1;
79	#if SIGNED
80	pDestinationBuffer[i] = (normalizer * (float) (iSign * iLevel) - 1.0f) * pAmp[i]; // * pAmp[i] just to simulate some memory load
81	#else // unsigned
82	pDestinationBuffer[i] = normalizer * (float) (iSign * iLevel) * pAmp[i]; // * pAmp[i] just to simulate some memory load
83	#endif
84	}
85	}
86
87	stop_time = clock();
88	float elapsed_time = (stop_time - start_time) / (double(CLOCKS_PER_SEC) / 1000.0);
89	#if ! SILENT
90	printf("int math solution elapsed time: %1.0f ms\n", elapsed_time);
91	#endif
92
93	return elapsed_time;
94	}
95
96	// table lookup solution (currently disabled)
97	//
98	// This solution is not yet implemented in LinuxSampler yet and probably
99	// never will, I simply haven't found an architectures / system where this
100	// turned out to be the best solution and it introduces too many problems
101	// anyway. If you found an architecture where this seems to be the best
102	// solution, please let us know!
103	#if 0
104	float table_lookup(sample_t* pDestinationBuffer, float* pAmp, const int steps, const float frequency) {
105	// pro forma
106	const float r = frequency / SAMPLING_RATE; // frequency alteration quotient
107	#if SIGNED
108	float c = r * 4.0f;
109	#else
110	float c = r * 2.0f;
111	#endif
112	const int wl = (int) (SAMPLING_RATE / frequency); // wave length (in sample points)
113
114	// 'volatile' to avoid the cache to fudge the benchmark result
115	volatile float* pPrerenderingBuffer = new float[wl];
116
117	// prerendering of the triangular wave
118	{
119	float level = 0.0f;
120	for (int i = 0; i < wl; ++i) {
121	level += c;
122	#if SIGNED
123	if (level >= 1.0f) {
124	c = -c;
125	level = 1.0f;
126	}
127	else if (level <= -1.0f) {
128	c = -c;
129	level = -1.0f;
130	}
131	#else
132	if (level >= 1.0f) {
133	c = -c;
134	level = 1.0f;
135	}
136	else if (level <= 0.0f) {
137	c = -c;
138	level = 0.0f;
139	}
140	#endif
141	pPrerenderingBuffer[i] = level;
142	}
143	}
144
145	clock_t stop_time;
146	clock_t start_time = clock();
147
148	for (int run = 0; run < RUNS; run++) {
149	for (int i = 0; i < steps; ++i) {
150	pDestinationBuffer[i] = pPrerenderingBuffer[i % wl] * pAmp[i]; // * pAmp[i] just to simulate some memory load
151	}
152	}
153
154	stop_time = clock();
155	float elapsed_time = (stop_time - start_time) / (double(CLOCKS_PER_SEC) / 1000.0);
156	#if ! SILENT
157	printf("Table lookup solution elapsed time: %1.0f ms\n", elapsed_time);
158	#endif
159
160	if (pPrerenderingBuffer) delete[] pPrerenderingBuffer;
161
162	return elapsed_time;
163	}
164	#endif
165
166	// numeric, di-harmonic solution
167	float numeric_di_harmonic_solution(sample_t* pDestinationBuffer, float* pAmp, const int steps, const float frequency) {
168	// we approximate the triangular wave by adding 2 harmonics
169	const float c1 = 2.0f * M_PI * frequency / SAMPLING_RATE;
170	const float phi1 = 0.0f; // phase displacement
171	const float c2 = 2.0f * M_PI * frequency / SAMPLING_RATE * 3.0f;
172	const float phi2 = 0.0f; // phase displacement
173
174	// amplitue for the 2nd harmonic (to approximate the triangular wave)
175	const float amp2 = 0.1f;
176
177	// initial values for real and imaginary part
178	float real1 = cos(phi1);
179	float imag1 = sin(phi1);
180	float real2 = cos(phi2);
181	float imag2 = sin(phi2);
182
183	clock_t stop_time;
184	clock_t start_time = clock();
185
186	for (int run = 0; run < RUNS; run++) {
187	for (int i = 0; i < steps; i++) {
188	#if SIGNED
189	pDestinationBuffer[i] = (real1 + real2 * amp2) * pAmp[i]; // * pAmp[i] just to simulate some memory load
190	#else // unsigned
191	pDestinationBuffer[i] = ((real1 + real2 * amp2) * 0.5f + 0.5f) * pAmp[i]; // * pAmp[i] just to simulate some memory load
192	#endif
193	real1 -= c1 * imag1;
194	imag1 += c1 * real1;
195	real2 -= c2 * imag2;
196	imag2 += c2 * real2;
197	}
198	}
199
200	stop_time = clock();
201	float elapsed_time = (stop_time - start_time) / (double(CLOCKS_PER_SEC) / 1000.0);
202	#if ! SILENT
203	printf("Numeric harmonics solution elapsed time: %1.0f ms\n", elapsed_time);
204	#endif
205
206	return elapsed_time;
207	}
208
209	// output calculated values as RAW audio format (32 bit floating point, mono) file
210	void output_as_raw_file(const char* filename, sample_t* pOutputBuffer, int steps) {
211	FILE* file = fopen(filename, "w");
212	if (file) {
213	fwrite((void*) pOutputBuffer, sizeof(float), steps, file);
214	fclose(file);
215	} else {
216	fprintf(stderr, "Could not open %s\n", filename);
217	}
218	}
219
220	int main() {
221	const int steps = STEPS;
222	const int sinusoidFrequency = 100; // Hz
223
224	#if ! SILENT
225	# if SIGNED
226	printf("Signed triangular wave benchmark\n");
227	printf("--------------------------------\n");
228	# else
229	printf("Unsigned triangular wave benchmark\n");
230	printf("----------------------------------\n");
231	# endif
232	#endif
233
234	// output buffer for the calculated sinusoid wave
235	sample_t* pOutputBuffer = new sample_t[steps];
236	// just an arbitrary amplitude envelope to simulate a bit higher memory bandwidth
237	float* pAmplitude = new float[steps];
238
239	// pro forma - an arbitary amplitude envelope
240	for (int i = 0; i < steps; ++i)
241	pAmplitude[i] = (float) i / (float) steps;
242
243	// how long each solution took (in seconds)
244	float int_math_result, /table_lookup_result,/ numeric_di_harmonic_result;
245
246	int_math_result = int_math(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);
247	#if OUTPUT_AS_RAW_WAVE
248	output_as_raw_file("bench_int_math.raw", pOutputBuffer, steps);
249	#endif
250	//table_lookup_result = table_lookup(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);
251	//#if OUTPUT_AS_RAW_WAVE
252	// output_as_raw_file("bench_table_lookup.raw", pOutputBuffer, steps);
253	//#endif
254	numeric_di_harmonic_result = numeric_di_harmonic_solution(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);
255	#if OUTPUT_AS_RAW_WAVE
256	output_as_raw_file("bench_numeric_harmonics.raw", pOutputBuffer, steps);
257	#endif
258
259	#if ! SILENT
260	printf("\nOK, 2nd try\n\n");
261	#endif
262
263	int_math_result += int_math(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);
264	//table_lookup_result += table_lookup(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);
265	numeric_di_harmonic_result += numeric_di_harmonic_solution(pOutputBuffer, pAmplitude, steps, sinusoidFrequency);
266
267	if (pAmplitude) delete[] pAmplitude;
268	if (pOutputBuffer) delete[] pOutputBuffer;
269
270	if (/int_math_result <= table_lookup_result &&/ int_math_result <= numeric_di_harmonic_result) return INT_MATH_SOLUTION;
271	if (/numeric_di_harmonic_result <= table_lookup_result &&/ numeric_di_harmonic_result <= int_math_result) return DI_HARMONIC_SOLUTION;
272	//if (table_lookup_result <= int_math_result && table_lookup_result <= numeric_di_harmonic_result) return TABLE_LOOKUP_SOLUTION;
273
274	return INVALID_RESULT; // error
275	}