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Merged
cujomalainey merged 1 commit into from
Feb 11, 2022
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math: Add logarithm base E and base 10 #5074

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17 changes: 0 additions & 17 deletions src/include/sof/math/base2log.h
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21 changes: 21 additions & 0 deletions src/include/sof/math/log.h
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@@ -0,0 +1,21 @@
/* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright(c) 2021 Intel Corporation. All rights reserved.
*
* Author: Shriram Shastry <malladi.sastry@linux.intel.com>
*
*/

#ifndef __SOF_MATH_BASE_LOGARITHM_H__
#define __SOF_MATH_BASE_LOGARITHM_H__

#include <stdint.h>

#define ONE_OVER_LOG2_10 2647887844335ULL /* 1/log2(10),Q1.43 */
#define ONE_OVER_LOG2_E 6096987078286ULL /* 1/log2(exp(1)), Q1.43 */
/* Function Declarations */
int32_t base2_logarithm(uint32_t u);
uint32_t ln_int32(uint32_t numerator);
uint32_t log10_int32(uint32_t numerator);

#endif
8 changes: 8 additions & 0 deletions src/math/CMakeLists.txt
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Expand Up @@ -18,6 +18,14 @@ if(CONFIG_MATH_DECIBELS)
add_local_sources(sof decibels.c)
endif()

if(CONFIG_NATURAL_LOGARITHM_FIXED)
add_local_sources(sof log_e.c)
endif()

if(CONFIG_COMMON_LOGARITHM_FIXED)
add_local_sources(sof log_10.c)
endif()

if(CONFIG_POWER_FIXED)
add_local_sources(sof power.c)
endif()
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14 changes: 14 additions & 0 deletions src/math/Kconfig
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Expand Up @@ -38,6 +38,20 @@ config SQRT_FIXED
to calculate square root.square function having positive number
y as input and return the positive number x multiplied by itself (squared)

config NATURAL_LOGARITHM_FIXED
bool "Natural Logarithm function"
default n
help
This option builds Natural Logarithm function (loge(N)) which is the logarithm to
the base e.

config COMMON_LOGARITHM_FIXED
bool "Common Logarithm function"
default n
help
This option builds common Logarithm function (log10(N)) which is the logarithm to
the base 10.

config NUMBERS_GCD
bool "Greatest common divisor"
default n
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3 changes: 1 addition & 2 deletions src/math/base2log.c
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Expand Up @@ -6,8 +6,7 @@
//
//

/* Include Files */
#include <sof/math/base2log.h>
#include <sof/math/log.h>

/* Defines Constant*/
#define BASE2LOG_WRAP_SCHAR_BITS 0xFF
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32 changes: 32 additions & 0 deletions src/math/log_10.c
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@@ -0,0 +1,32 @@
// SPDX-License-Identifier: BSD-3-Clause/
//
// Copyright(c) 2021 Intel Corporation. All rights reserved.
//
// Author: Shriram Shastry <malladi.sastry@linux.intel.com>
//
//

#include <sof/math/log.h>
#include <sof/audio/format.h>
/**
* Base-10 logarithm log10(x)
*
* loge = (u) computes the base-10 logarithm of
* u using lookup table.
* input u must be scalar/real number and positive
*
* +------------------+-----------------+--------+--------+
* | inpfxp |log10(returntype)| inpfxp | loge |
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* +----+-----+-------+----+----+-------+--------+--------+
* |WLen| FLen|Signbit|WLen|FLen|Signbit| Qformat| Qformat|
* +----+-----+-------+----+----+-------+--------+--------+
* | 32 | 0 | 0 | 32 | 28 | 0 | 32.0 | 4.28 |
* +------------------+-----------------+--------+--------+
* Arguments : uint32_t numerator [1 to 4294967295, Q32.0]
* Return Type : uint32_t UQ4.28 [0 to 9.6329499409]
*/
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uint32_t log10_int32(uint32_t numerator)

@cujomalainey cujomalainey Feb 3, 2022

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You still need to add the inline keyword to get the optimization

@marc-hb marc-hb Feb 3, 2022

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I compared gcc and clang outputs a number of times and I've never seen inline making any difference, at least never with -On where n > 0. The optimizer always thinks it knows better. That's why there is non-portable stuff like ALWAYS_INLINE.

(static inline is still useful in .h files to silence some warnings)

@cujomalainey cujomalainey Feb 3, 2022

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given we know xcc isnt the smartest sometimes i think it is still wise to have the hints for it

@ShriramShastry ShriramShastry Feb 9, 2022 •
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if I change to inline ln_int32() and inline log10_int32(), I could see below error

No codespell typos will be found - file '/usr/share/codespell/dictionary.txt': No such file or directory
ERROR: inline keyword should sit between storage class and type
#10: FILE: src/math/log_10.c:28:
+uint32_t inline log10_int32(uint32_t numerator)

ERROR: inline keyword should sit between storage class and type
#23: FILE: src/math/log_e.c:29:
+uint32_t inline ln_int32(uint32_t numerator)

In case I make changes in log.h like below

static inline uint32_t ln_int32(uint32_t numerator)
{
	return((uint32_t)Q_SHIFT_RND((int64_t)base2_logarithm(numerator) *
				     ONE_OVER_LOG2_E, 64, 32));
}
static inline uint32_t log10_int32(uint32_t numerator)
{
		return((uint32_t)Q_SHIFT_RND((int64_t)base2_logarithm(numerator) *
				     ONE_OVER_LOG2_10, 63, 32));
}

then log10_int32(uint32_t numerator) and ln_int32(uint32_t numerator) in log_10.c and log_e.c will be redundant, the impact of removing log_10.c and log_e.c will result in error in cmocka compilation. cmocka CmakeList.txt is using of log_10.c and log_e.c files.

cmocka_test(base_10_logarithm
	base_10_logarithm.c
	${PROJECT_SOURCE_DIR}/src/math/log_10.c
	${PROJECT_SOURCE_DIR}/src/math/base2log.c
)

cmocka_test(base_e_logarithm
	base_e_logarithm.c
	${PROJECT_SOURCE_DIR}/src/math/log_e.c
	${PROJECT_SOURCE_DIR}/src/math/base2log.c
)

{
return((uint32_t)Q_SHIFT_RND((int64_t)base2_logarithm(numerator) *
ONE_OVER_LOG2_10, 63, 32));
}
33 changes: 33 additions & 0 deletions src/math/log_e.c
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// SPDX-License-Identifier: BSD-3-Clause
//
// Copyright(c) 2021 Intel Corporation. All rights reserved.
//
// Author: Shriram Shastry <malladi.sastry@linux.intel.com>
//
//

#include <sof/math/log.h>
#include <sof/audio/format.h>
/**
* Base-e logarithm loge(x)
*
* loge = (u) computes the base-e logarithm of
* u using lookup table.
* input u must be scalar/real number and positive
*
* +------------------+-----------------+--------+--------+
* | inpfxp |loge (returntype)| inpfxp | loge |
* +----+-----+-------+----+----+-------+--------+--------+
* |WLen| FLen|Signbit|WLen|FLen|Signbit| Qformat| Qformat|
* +----+-----+-------+----+----+-------+--------+--------+
* | 32 | 0 | 0 | 32 | 27 | 0 | 32.0 | 5.27 |
* +------------------+-----------------+--------+--------+
*
* Arguments : uint32_t numerator [1 to 4294967295- Q32.0]
* Return Type : uint32_t UQ5.27 [ 0 to 22.1808076352]
*/
uint32_t ln_int32(uint32_t numerator)
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{
return((uint32_t)Q_SHIFT_RND((int64_t)base2_logarithm(numerator) *
ONE_OVER_LOG2_E, 64, 32));
}
12 changes: 12 additions & 0 deletions test/cmocka/src/math/arithmetic/CMakeLists.txt
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Expand Up @@ -14,3 +14,15 @@ cmocka_test(square_root
square_root.c
${PROJECT_SOURCE_DIR}/src/math/sqrt_int16.c
)

cmocka_test(base_10_logarithm
base_10_logarithm.c
${PROJECT_SOURCE_DIR}/src/math/log_10.c
${PROJECT_SOURCE_DIR}/src/math/base2log.c
)

cmocka_test(base_e_logarithm
base_e_logarithm.c
${PROJECT_SOURCE_DIR}/src/math/log_e.c
${PROJECT_SOURCE_DIR}/src/math/base2log.c
)
2 changes: 1 addition & 1 deletion test/cmocka/src/math/arithmetic/base2_logarithm.c
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Expand Up @@ -13,7 +13,7 @@
#include <cmocka.h>
#include <string.h>

#include <sof/math/base2log.h>
#include <sof/math/log.h>
#include <sof/audio/format.h>
#include <sof/string.h>
#include <sof/common.h>
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105 changes: 105 additions & 0 deletions test/cmocka/src/math/arithmetic/base_10_logarithm.c
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// SPDX-License-Identifier: BSD-3-Clause
//
// Copyright(c) 2021 Intel Corporation. All rights reserved.
//
// Author: Shriram Shastry <malladi.sastry@linux.intel.com>
//
//

#include <stdio.h>
#include <stdint.h>
#include <stdarg.h>
#include <stddef.h>
#include <setjmp.h>
#include <math.h>
#include <cmocka.h>
#include <string.h>

#include <sof/math/log.h>
#include <sof/audio/format.h>
#include <sof/string.h>
#include <sof/common.h>
#include "log2_tables.h"
/* 'Error[max] = 0.0000071279028671,THD = -102.9407645424143993 ' */
/* 'Error[max] = rms(log10() - double(log10_int32()))' */
/* 'THD = 20*log10(Error[max])' */
#define CMP_TOLERANCE 0.0000071279028671
/* Natural logarithm log10(X) reference table generated by matlab/Octave */

@marc-hb marc-hb Dec 20, 2021

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Why not just use <math.h>'s log functions, why is this table needed?

@ShriramShastry ShriramShastry Dec 21, 2021 •
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Using book & pen/manual calculation log() calculation, In most of the cases results are more closer to Matlab/Octave log function . So i am considering matlab /octave more accurate in precision than built-in <math.h>, library functions.

@ShriramShastry ShriramShastry Dec 21, 2021 •
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Log table is a reference table which is derived from offline log function using Octave/matlab. Reference table values are compared against fix point log_10_int32 function.

@lgirdwood lgirdwood Dec 21, 2021

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@marc-hb we dont use C lib maths as they are not optimised for xtensa or SOF formats.

@marc-hb marc-hb Feb 2, 2022

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This seems vulnerable to a copy/paste typo. Is there some redundancy built in in the test? If not, then adding another test, very simple test using <math.h> (when available) would provide that redundancy.

/* UQ4.28 */
static const double common_log10_ref_table[] = {
0.0000000000000000, 7.6373246662453802, 7.9383546619093615, 8.1144459209650428,
8.2393846575733427, 8.3362946705813989, 8.4154759166290241, 8.4824227062596371,
8.5404146532373240, 8.5915671756847054, 8.6373246662453802, 8.6787173514036056,
8.7165059122930053, 8.7512680193222625, 8.7834527026386606, 8.8134159259684335,
8.8414446495269665, 8.8677735882125130, 8.8925971719048302, 8.9160782677250818,
8.9383546624098908, 8.9595439614559940, 8.9797473475226131, 8.9990525026982162,
9.0175359083740947, 9.0352646753178405, 9.0522980146012202, 9.0686884307751292,
9.0844826979451199, 9.0997226644895282, 9.1144459212987297, 9.1286863604025754,
9.1424746448781171, 9.1558386064266184, 9.1688035835820649, 9.1813927108816724,
9.1936271672907388, 9.2055263908534872, 9.2171082633890631, 9.2283892737852433,
9.2393846580738721, 9.2501085234534361, 9.2605739571199752, 9.2707931222905753,
9.2807773431865943, 9.2905371804656394, 9.3000824983621975, 9.3094225246070792,
9.3185659040380759, 9.3275207466824899, 9.3362946709818218, 9.3448948427358882,
9.3533280102652014, 9.3616005362239267, 9.3697184264391105, 9.3776873561036460,
9.3855126936091011, 9.3931995222691196, 9.4007526601535094, 9.4081766782268659,
9.4154759169627091, 9.4226545015843630, 9.4297163562280168, 9.4366652161756566,
9.4435046406985137, 9.4502380233502628, 9.4568686022422757, 9.4633994693944423,
9.4698335793932600, 9.4761737574178788, 9.4824227066886628, 9.4885830153874373,
9.4946571630937573, 9.5006475267772306, 9.5065563863821918, 9.5123859300375031,
9.5181382589213257, 9.5238153918078847, 9.5294192693208828, 9.5349517579159713,
9.5404146536127215, 9.5458096854947918, 9.5511385189953373, 9.5564027589832818,
9.5616039526647825, 9.5667435923129869, 9.5718231178381536, 9.5768439193242560,
9.5818073388505756, 9.5867146733402073, 9.5915671761296206, 9.5963660590064990,
9.6011124940261787, 9.6058076152298781, 9.6104525202710605, 9.6150482719557271,
9.6195958997020572, 9.6240964009244330, 9.6285507423464711, 9.6329598611462810};

/* testvector in Q32.0 */
static const uint32_t uv[100] = {
1ULL, 43383509ULL, 86767017ULL, 130150525ULL, 173534033ULL, 216917541ULL,
260301049ULL, 303684557ULL, 347068065ULL, 390451573ULL, 433835081ULL, 477218589ULL,
520602097ULL, 563985605ULL, 607369113ULL, 650752621ULL, 694136129ULL, 737519638ULL,
780903146ULL, 824286654ULL, 867670162ULL, 911053670ULL, 954437178ULL, 997820686ULL,
1041204194ULL, 1084587702ULL, 1127971210ULL, 1171354718ULL, 1214738226ULL, 1258121734ULL,
1301505242ULL, 1344888750ULL, 1388272258ULL, 1431655766ULL, 1475039274ULL, 1518422782ULL,
1561806290ULL, 1605189798ULL, 1648573306ULL, 1691956814ULL, 1735340322ULL, 1778723830ULL,
1822107338ULL, 1865490846ULL, 1908874354ULL, 1952257862ULL, 1995641370ULL, 2039024878ULL,
2082408386ULL, 2125791894ULL, 2169175403ULL, 2212558911ULL, 2255942419ULL, 2299325927ULL,
2342709435ULL, 2386092943ULL, 2429476451ULL, 2472859959ULL, 2516243467ULL, 2559626975ULL,
2603010483ULL, 2646393991ULL, 2689777499ULL, 2733161007ULL, 2776544515ULL, 2819928023ULL,
2863311531ULL, 2906695039ULL, 2950078547ULL, 2993462055ULL, 3036845563ULL, 3080229071ULL,
3123612579ULL, 3166996087ULL, 3210379595ULL, 3253763103ULL, 3297146611ULL, 3340530119ULL,
3383913627ULL, 3427297135ULL, 3470680643ULL, 3514064151ULL, 3557447659ULL, 3600831168ULL,
3644214676ULL, 3687598184ULL, 3730981692ULL, 3774365200ULL, 3817748708ULL, 3861132216ULL,
3904515724ULL, 3947899232ULL, 3991282740ULL, 4034666248ULL, 4078049756ULL, 4121433264ULL,
4164816772ULL, 4208200280ULL, 4251583788ULL, 4294967295ULL};

static void test_math_arithmetic_base10log_fixed(void **state)
{
(void)state;

double clogfxp;
double diff;
int i;

for (i = 0; i < ARRAY_SIZE(common_log10_ref_table); i++) {
clogfxp = log10_int32(uv[i]);
diff = fabs(common_log10_ref_table[i] - (double)clogfxp / (1 << 28));

if (diff > CMP_TOLERANCE) {
printf("%s: diff for %.16f: val = %16d, log10() = %.16f\n", __func__, diff,
uv[i], clogfxp / (1 << 28));
assert_true(diff <= CMP_TOLERANCE);
}
}
}

int main(void)
{
const struct CMUnitTest tests[] = {
cmocka_unit_test(test_math_arithmetic_base10log_fixed)
};

cmocka_set_message_output(CM_OUTPUT_TAP);

return cmocka_run_group_tests(tests, NULL, NULL);
}
104 changes: 104 additions & 0 deletions test/cmocka/src/math/arithmetic/base_e_logarithm.c
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// SPDX-License-Identifier: BSD-3-Clause
//
// Copyright(c) 2021 Intel Corporation. All rights reserved.
//
// Author: Shriram Shastry <malladi.sastry@linux.intel.com>

#include <stdio.h>
#include <stdint.h>
#include <stdarg.h>
#include <stddef.h>
#include <setjmp.h>
#include <math.h>
#include <cmocka.h>
#include <string.h>

#include <sof/math/log.h>
#include <sof/audio/format.h>
#include <sof/string.h>
#include <sof/common.h>
#include "log2_tables.h"
/* 'Error[max] = 0.0000164133276926,THD(-dBc) = -95.6960671942683234' */
/* 'Error[max] = rms(log() - double(log_int32()))' */
/* 'THD = 20*log10(Error[max])' */
#define CMP_TOLERANCE 0.0000164133276926

/* Natural logarithm loge(X) reference table generated by matlab/Octave */
/* UQ5.27 */
static const double natural_log_lookup_table[] = {
0.0000000000000000, 17.5855899268523359, 18.2787371074122831, 18.6842022155204468,
18.9718842879722267, 19.1950278392864391, 19.3773493960803940, 19.5315000759076511,
19.6650314685321739, 19.7828145041885577, 19.8881750198463827, 19.9834851996507084,
20.0704965766403376, 20.1505392860869676, 20.2246472581140395, 20.2936401294912301,
20.3581786505327571, 20.4188032722644479, 20.4759616860290699, 20.5300289072319480,
20.5813222015588408, 20.6301123656733907, 20.6766323812583899, 20.7210841437836706,
20.7636437581607112, 20.8044657526425461, 20.8436864657603671, 20.8814267937103786,
20.9177944378507625, 20.9528857576336485, 20.9867873092828354, 21.0195771320810394,
21.0513258303723845, 21.0820974890173112, 21.1119504521464485, 21.1409379890003279,
21.1691088659487328, 21.1965078407425196, 21.2231760877918916, 21.2491515741640455,
21.2744693821187845, 21.2991619946810467, 21.3232595462333343, 21.3467900436180038,
21.3697795618183370, 21.3922524176471107, 21.4142313243436178, 21.4357375295432568,
21.4567909387206548, 21.4774102259037889, 21.4976129332024932, 21.5174155604805932,
21.5368336463203107, 21.5558818412742781, 21.5745739742703257, 21.5929231129229997,
21.6109416184107097, 21.6286411954956677, 21.6460329381935921, 21.6631273715394208,
21.6799344898427790, 21.6964637917813938, 21.7127243130127638, 21.7287246543415016,
21.7444730112924880, 21.7599771978118319, 21.7752446699265008, 21.7902825472754031,
21.8050976330453672, 21.8196964324517815, 21.8340851698895619, 21.8482698048676056,
21.8622560468288185, 21.8760493689479993, 21.8896550209909755, 21.9030780413106569,
21.9163232680485471, 21.9293953496040821, 21.9422987544284780, 21.9550377801946830,
21.9676165623906030, 21.9800390823784895, 21.9923091749598925, 22.0044305354820757,
22.0164067265188734, 22.0282411841561903, 22.0399372239099236, 22.0514980465667030,
22.0629267423782807, 22.0742262976204415, 22.0853995982070579, 22.0964494343823858,
22.1073785049035614, 22.1181894209970018, 22.1288847101032040, 22.1394668194234150,
22.1499381192805984, 22.1603009063062437, 22.1705574064637361, 22.1807097776854185};

/* testvector in Q32.0 */
static const uint32_t uv[100] = {
1ULL, 43383509ULL, 86767017ULL, 130150525ULL, 173534033ULL, 216917541ULL,
260301049ULL, 303684557ULL, 347068065ULL, 390451573ULL, 433835081ULL, 477218589ULL,
520602097ULL, 563985605ULL, 607369113ULL, 650752621ULL, 694136129ULL, 737519638ULL,
780903146ULL, 824286654ULL, 867670162ULL, 911053670ULL, 954437178ULL, 997820686ULL,
1041204194ULL, 1084587702ULL, 1127971210ULL, 1171354718ULL, 1214738226ULL, 1258121734ULL,
1301505242ULL, 1344888750ULL, 1388272258ULL, 1431655766ULL, 1475039274ULL, 1518422782ULL,
1561806290ULL, 1605189798ULL, 1648573306ULL, 1691956814ULL, 1735340322ULL, 1778723830ULL,
1822107338ULL, 1865490846ULL, 1908874354ULL, 1952257862ULL, 1995641370ULL, 2039024878ULL,
2082408386ULL, 2125791894ULL, 2169175403ULL, 2212558911ULL, 2255942419ULL, 2299325927ULL,
2342709435ULL, 2386092943ULL, 2429476451ULL, 2472859959ULL, 2516243467ULL, 2559626975ULL,
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2863311531ULL, 2906695039ULL, 2950078547ULL, 2993462055ULL, 3036845563ULL, 3080229071ULL,
3123612579ULL, 3166996087ULL, 3210379595ULL, 3253763103ULL, 3297146611ULL, 3340530119ULL,
3383913627ULL, 3427297135ULL, 3470680643ULL, 3514064151ULL, 3557447659ULL, 3600831168ULL,
3644214676ULL, 3687598184ULL, 3730981692ULL, 3774365200ULL, 3817748708ULL, 3861132216ULL,
3904515724ULL, 3947899232ULL, 3991282740ULL, 4034666248ULL, 4078049756ULL, 4121433264ULL,
4164816772ULL, 4208200280ULL, 4251583788ULL, 4294967295ULL};

static void test_math_arithmetic_base_e_log_fixed(void **state)
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{
(void)state;

double logefxp;
double diff;
int i;

for (i = 0; i < ARRAY_SIZE(natural_log_lookup_table); i++) {
logefxp = ln_int32(uv[i]);
diff = fabs(natural_log_lookup_table[i] - (double)logefxp / (1 << 27));

if (diff > CMP_TOLERANCE) {
printf("%s: diff for %.16f: value = %16d, log() = %.16f\n", __func__, diff,
uv[i], logefxp / (1 << 27));
assert_true(diff <= CMP_TOLERANCE);
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}
}
}

int main(void)
{
const struct CMUnitTest tests[] = {
cmocka_unit_test(test_math_arithmetic_base_e_log_fixed)
};

cmocka_set_message_output(CM_OUTPUT_TAP);

return cmocka_run_group_tests(tests, NULL, NULL);
}