1 /**************************************************************************/
2 /* */
3 /* Copyright (c) Microsoft Corporation. All rights reserved. */
4 /* */
5 /* This software is licensed under the Microsoft Software License */
6 /* Terms for Microsoft Azure RTOS. Full text of the license can be */
7 /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
8 /* and in the root directory of this software. */
9 /* */
10 /**************************************************************************/
11
12
13 /**************************************************************************/
14 /**************************************************************************/
15 /** */
16 /** GUIX Component */
17 /** */
18 /** Utility (Utility) */
19 /** */
20 /**************************************************************************/
21
22 #define GX_SOURCE_CODE
23
24
25 /* Include necessary system files. */
26
27 #include "gx_api.h"
28 #include "gx_utility.h"
29
30
31 static GX_CONST GX_UBYTE sqrt_table[256] = {
32 0x00, 0x10, 0x16, 0x1b, 0x20, 0x23, 0x27, 0x2a, 0x2d, 0x30, 0x32, 0x35, 0x37, 0x39, 0x3b,
33 0x3d, 0x40, 0x41, 0x43, 0x45, 0x47, 0x49, 0x4b, 0x4c, 0x4e, 0x50, 0x51, 0x53, 0x54, 0x56,
34 0x57, 0x59, 0x5a, 0x5b, 0x5d, 0x5e, 0x60, 0x61, 0x62, 0x63, 0x65, 0x66, 0x67, 0x68, 0x6a,
35 0x6b, 0x6c, 0x6d, 0x6e, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a,
36 0x7b, 0x7c, 0x7d, 0x7e, 0x80, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
37 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x96,
38 0x97, 0x98, 0x99, 0x9a, 0x9b, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, 0xa0, 0xa0, 0xa1, 0xa2, 0xa3,
39 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa7, 0xa8, 0xa9, 0xaa, 0xaa, 0xab, 0xac, 0xad, 0xad, 0xae,
40 0xaf, 0xb0, 0xb0, 0xb1, 0xb2, 0xb2, 0xb3, 0xb4, 0xb5, 0xb5, 0xb6, 0xb7, 0xb7, 0xb8, 0xb9,
41 0xb9, 0xba, 0xbb, 0xbb, 0xbc, 0xbd, 0xbd, 0xbe, 0xbf, 0xc0, 0xc0, 0xc1, 0xc1, 0xc2, 0xc3,
42 0xc3, 0xc4, 0xc5, 0xc5, 0xc6, 0xc7, 0xc7, 0xc8, 0xc9, 0xc9, 0xca, 0xcb, 0xcb, 0xcc, 0xcc,
43 0xcd, 0xce, 0xce, 0xcf, 0xd0, 0xd0, 0xd1, 0xd1, 0xd2, 0xd3, 0xd3, 0xd4, 0xd4, 0xd5, 0xd6,
44 0xd6, 0xd7, 0xd7, 0xd8, 0xd9, 0xd9, 0xda, 0xda, 0xdb, 0xdb, 0xdc, 0xdd, 0xdd, 0xde, 0xde,
45 0xdf, 0xe0, 0xe0, 0xe1, 0xe1, 0xe2, 0xe2, 0xe3, 0xe3, 0xe4, 0xe5, 0xe5, 0xe6, 0xe6, 0xe7,
46 0xe7, 0xe8, 0xe8, 0xe9, 0xea, 0xea, 0xeb, 0xeb, 0xec, 0xec, 0xed, 0xed, 0xee, 0xee, 0xef,
47 0xf0, 0xf0, 0xf1, 0xf1, 0xf2, 0xf2, 0xf3, 0xf3, 0xf4, 0xf4, 0xf5, 0xf5, 0xf6, 0xf6, 0xf7,
48 0xf7, 0xf8, 0xf8, 0xf9, 0xf9, 0xfa, 0xfa, 0xfb, 0xfb, 0xfc, 0xfc, 0xfd, 0xfd, 0xfe, 0xfe,
49 0xff
50 };
51
52
53
54 /**************************************************************************/
55 /* */
56 /* FUNCTION RELEASE */
57 /* */
58 /* _gx_utility_math_sqrt PORTABLE C */
59 /* 6.1 */
60 /* AUTHOR */
61 /* */
62 /* Kenneth Maxwell, Microsoft Corporation */
63 /* */
64 /* DESCRIPTION */
65 /* */
66 /* This service computes the square root of the supplied value. */
67 /* */
68 /* INPUT */
69 /* */
70 /* value Value to compute square */
71 /* root of */
72 /* */
73 /* OUTPUT */
74 /* */
75 /* square_root Square root of supplied value */
76 /* */
77 /* CALLS */
78 /* */
79 /* None */
80 /* */
81 /* CALLED BY */
82 /* */
83 /* Application Code */
84 /* */
85 /* RELEASE HISTORY */
86 /* */
87 /* DATE NAME DESCRIPTION */
88 /* */
89 /* 05-19-2020 Kenneth Maxwell Initial Version 6.0 */
90 /* 09-30-2020 Kenneth Maxwell Modified comment(s), */
91 /* resulting in version 6.1 */
92 /* */
93 /**************************************************************************/
94
_gx_utility_math_sqrt(UINT value)95 UINT _gx_utility_math_sqrt(UINT value)
96 {
97 UINT square_root;
98
99 if (value >= 0x7FFEA810)
100 {
101 square_root = 0xB504;
102 }
103 else if (value >= 0x1000000)
104 {
105 if (value >= 0x40000000)
106 {
107 square_root = (UINT)sqrt_table[value >> 24] << 8;
108 }
109 else if (value >= 0x10000000)
110 {
111 square_root = (UINT)sqrt_table[value >> 22] << 7;
112 }
113 else if (value >= 0x4000000)
114 {
115 square_root = (UINT)sqrt_table[value >> 20] << 6;
116 }
117 else
118 {
119 square_root = (UINT)sqrt_table[value >> 18] << 5;
120 }
121
122 square_root = (square_root + 1 + (value / square_root)) >> 1;
123 square_root = (square_root + 1 + (value / square_root)) >> 1;
124 }
125 else if (value >= 0x10000)
126 {
127 if (value >= 0x400000)
128 {
129 square_root = (UINT)sqrt_table[value >> 16] << 4;
130 }
131 else if (value >= 0x100000)
132 {
133 square_root = (UINT)sqrt_table[value >> 14] << 3;
134 }
135 else if (value >= 0x40000)
136 {
137 square_root = (UINT)sqrt_table[value >> 12] << 2;
138 }
139 else
140 {
141 square_root = (UINT)sqrt_table[value >> 10] << 1;
142 }
143
144 square_root = (square_root + 1 + (value / square_root)) >> 1;
145 }
146 else
147 {
148 if (value >= 0x4000)
149 {
150 square_root = (UINT)(sqrt_table[value >> 8]) + 1;
151 }
152 else if (value >= 0x1000)
153 {
154 square_root = (UINT)(sqrt_table[value >> 6] >> 1) + 1;
155 }
156 else if (value >= 0x400)
157 {
158 square_root = (UINT)(sqrt_table[value >> 4] >> 2) + 1;
159 }
160 else if (value >= 0x100)
161 {
162 square_root = (UINT)(sqrt_table[value >> 2] >> 3) + 1;
163 }
164 else
165 {
166 square_root = sqrt_table[value] >> 4;
167 }
168 }
169
170 if ((square_root * square_root) > value)
171 {
172 square_root--;
173 }
174
175 return square_root;
176 }
177
178
