diff options
| author | Meco Man <[email protected]> | 2021-02-23 03:28:19 +0800 |
|---|---|---|
| committer | Meco Man <[email protected]> | 2021-02-23 03:28:19 +0800 |
| commit | 497e7b45d489802a16bf2bba97efa7f303e88206 (patch) | |
| tree | d32b82b339dd3fc0a930c4c963f12d4f94917076 /components/libc/compilers/minilibc/math.c | |
| parent | b2d3317c6a7954423167316436c949fbcb1ce61d (diff) | |
remove minilibc
Diffstat (limited to 'components/libc/compilers/minilibc/math.c')
| -rw-r--r-- | components/libc/compilers/minilibc/math.c | 176 |
1 files changed, 0 insertions, 176 deletions
diff --git a/components/libc/compilers/minilibc/math.c b/components/libc/compilers/minilibc/math.c deleted file mode 100644 index cd5770178e..0000000000 --- a/components/libc/compilers/minilibc/math.c +++ /dev/null @@ -1,176 +0,0 @@ -/* - * Copyright (c) 2006-2018, RT-Thread Development Team - * - * SPDX-License-Identifier: Apache-2.0 - * - * Change Logs: - * Date Author Notes - */ -#include <math.h> - -/* - * COPYRIGHT: See COPYING in the top level directory - * PROJECT: ReactOS CRT - * FILE: lib/crt/math/cos.c - * PURPOSE: Generic C Implementation of cos - * PROGRAMMER: Timo Kreuzer ([email protected]) - */ - -#define PRECISION 9 - -static double cos_off_tbl[] = {0.0, -M_PI/2., 0, -M_PI/2.}; -static double cos_sign_tbl[] = {1,-1,-1,1}; - -static double sin_off_tbl[] = {0.0, -M_PI/2., 0, -M_PI/2.}; -static double sin_sign_tbl[] = {1,-1,-1,1}; - -double sin(double x) -{ - int quadrant; - double x2, result; - - /* Calculate the quadrant */ - quadrant = x * (2./M_PI); - - /* Get offset inside quadrant */ - x = x - quadrant * (M_PI/2.); - - /* Normalize quadrant to [0..3] */ - quadrant = (quadrant - 1) & 0x3; - - /* Fixup value for the generic function */ - x += sin_off_tbl[quadrant]; - - /* Calculate the negative of the square of x */ - x2 = - (x * x); - - /* This is an unrolled taylor series using <PRECISION> iterations - * Example with 4 iterations: - * result = 1 - x^2/2! + x^4/4! - x^6/6! + x^8/8! - * To save multiplications and to keep the precision high, it's performed - * like this: - * result = 1 - x^2 * (1/2! - x^2 * (1/4! - x^2 * (1/6! - x^2 * (1/8!)))) - */ - - /* Start with 0, compiler will optimize this away */ - result = 0; - -#if (PRECISION >= 10) - result += 1./(1.*2*3*4*5*6*7*8*9*10*11*12*13*14*15*16*17*18*19*20); - result *= x2; -#endif -#if (PRECISION >= 9) - result += 1./(1.*2*3*4*5*6*7*8*9*10*11*12*13*14*15*16*17*18); - result *= x2; -#endif -#if (PRECISION >= 8) - result += 1./(1.*2*3*4*5*6*7*8*9*10*11*12*13*14*15*16); - result *= x2; -#endif -#if (PRECISION >= 7) - result += 1./(1.*2*3*4*5*6*7*8*9*10*11*12*13*14); - result *= x2; -#endif -#if (PRECISION >= 6) - result += 1./(1.*2*3*4*5*6*7*8*9*10*11*12); - result *= x2; -#endif -#if (PRECISION >= 5) - result += 1./(1.*2*3*4*5*6*7*8*9*10); - result *= x2; -#endif - result += 1./(1.*2*3*4*5*6*7*8); - result *= x2; - - result += 1./(1.*2*3*4*5*6); - result *= x2; - - result += 1./(1.*2*3*4); - result *= x2; - - result += 1./(1.*2); - result *= x2; - - result += 1; - - /* Apply correct sign */ - result *= sin_sign_tbl[quadrant]; - - return result; -} - -double cos(double x) -{ - int quadrant; - double x2, result; - - /* Calculate the quadrant */ - quadrant = x * (2./M_PI); - - /* Get offset inside quadrant */ - x = x - quadrant * (M_PI/2.); - - /* Normalize quadrant to [0..3] */ - quadrant = quadrant & 0x3; - - /* Fixup value for the generic function */ - x += cos_off_tbl[quadrant]; - - /* Calculate the negative of the square of x */ - x2 = - (x * x); - - /* This is an unrolled taylor series using <PRECISION> iterations - * Example with 4 iterations: - * result = 1 - x^2/2! + x^4/4! - x^6/6! + x^8/8! - * To save multiplications and to keep the precision high, it's performed - * like this: - * result = 1 - x^2 * (1/2! - x^2 * (1/4! - x^2 * (1/6! - x^2 * (1/8!)))) - */ - - /* Start with 0, compiler will optimize this away */ - result = 0; - -#if (PRECISION >= 10) - result += 1./(1.*2*3*4*5*6*7*8*9*10*11*12*13*14*15*16*17*18*19*20); - result *= x2; -#endif -#if (PRECISION >= 9) - result += 1./(1.*2*3*4*5*6*7*8*9*10*11*12*13*14*15*16*17*18); - result *= x2; -#endif -#if (PRECISION >= 8) - result += 1./(1.*2*3*4*5*6*7*8*9*10*11*12*13*14*15*16); - result *= x2; -#endif -#if (PRECISION >= 7) - result += 1./(1.*2*3*4*5*6*7*8*9*10*11*12*13*14); - result *= x2; -#endif -#if (PRECISION >= 6) - result += 1./(1.*2*3*4*5*6*7*8*9*10*11*12); - result *= x2; -#endif -#if (PRECISION >= 5) - result += 1./(1.*2*3*4*5*6*7*8*9*10); - result *= x2; -#endif - result += 1./(1.*2*3*4*5*6*7*8); - result *= x2; - - result += 1./(1.*2*3*4*5*6); - result *= x2; - - result += 1./(1.*2*3*4); - result *= x2; - - result += 1./(1.*2); - result *= x2; - - result += 1; - - /* Apply correct sign */ - result *= cos_sign_tbl[quadrant]; - - return result; -} - |
