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comparison druntime/import/std/intrinsic.di @ 760:6f33b427bfd1

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Seems like hg ignores .di files, so I missed a bunch of stuff. complete druntime should be there now :)
author Tomas Lindquist Olsen <tomas.l.olsen@gmail.com>
date Wed, 12 Nov 2008 00:19:18 +0100
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1 /**
2 * These functions are built-in intrinsics to the compiler.
3 *
4 * Intrinsic functions are functions built in to the compiler, usually to take
5 * advantage of specific CPU features that are inefficient to handle via
6 * external functions. The compiler's optimizer and code generator are fully
7 * integrated in with intrinsic functions, bringing to bear their full power on
8 * them. This can result in some surprising speedups.
9 *
10 * Copyright: Public Domain
11 * License: Public Domain
12 * Authors: Walter Bright
13 */
14 module std.intrinsic;
15
16
17 /**
18 * Scans the bits in v starting with bit 0, looking
19 * for the first set bit.
20 * Returns:
21 * The bit number of the first bit set.
22 * The return value is undefined if v is zero.
23 */
24 int bsf( uint v );
25
26
27 /**
28 * Scans the bits in v from the most significant bit
29 * to the least significant bit, looking
30 * for the first set bit.
31 * Returns:
32 * The bit number of the first bit set.
33 * The return value is undefined if v is zero.
34 * Example:
35 * ---
36 * import std.intrinsic;
37 *
38 * int main()
39 * {
40 * uint v;
41 * int x;
42 *
43 * v = 0x21;
44 * x = bsf(v);
45 * printf("bsf(x%x) = %d\n", v, x);
46 * x = bsr(v);
47 * printf("bsr(x%x) = %d\n", v, x);
48 * return 0;
49 * }
50 * ---
51 * Output:
52 * bsf(x21) = 0<br>
53 * bsr(x21) = 5
54 */
55 int bsr( uint v );
56
57
58 /**
59 * Tests the bit.
60 */
61 int bt( const uint* p, uint bitnum );
62
63
64 /**
65 * Tests and complements the bit.
66 */
67 int btc( uint* p, uint bitnum );
68
69
70 /**
71 * Tests and resets (sets to 0) the bit.
72 */
73 int btr( uint* p, uint bitnum );
74
75
76 /**
77 * Tests and sets the bit.
78 * Params:
79 * p = a non-NULL pointer to an array of uints.
80 * index = a bit number, starting with bit 0 of p[0],
81 * and progressing. It addresses bits like the expression:
82 ---
83 p[index / (uint.sizeof*8)] & (1 << (index & ((uint.sizeof*8) - 1)))
84 ---
85 * Returns:
86 * A non-zero value if the bit was set, and a zero
87 * if it was clear.
88 *
89 * Example:
90 * ---
91 import std.intrinsic;
92
93 int main()
94 {
95 uint array[2];
96
97 array[0] = 2;
98 array[1] = 0x100;
99
100 printf("btc(array, 35) = %d\n", <b>btc</b>(array, 35));
101 printf("array = [0]:x%x, [1]:x%x\n", array[0], array[1]);
102
103 printf("btc(array, 35) = %d\n", <b>btc</b>(array, 35));
104 printf("array = [0]:x%x, [1]:x%x\n", array[0], array[1]);
105
106 printf("bts(array, 35) = %d\n", <b>bts</b>(array, 35));
107 printf("array = [0]:x%x, [1]:x%x\n", array[0], array[1]);
108
109 printf("btr(array, 35) = %d\n", <b>btr</b>(array, 35));
110 printf("array = [0]:x%x, [1]:x%x\n", array[0], array[1]);
111
112 printf("bt(array, 1) = %d\n", <b>bt</b>(array, 1));
113 printf("array = [0]:x%x, [1]:x%x\n", array[0], array[1]);
114
115 return 0;
116 }
117 * ---
118 * Output:
119 <pre>
120 btc(array, 35) = 0
121 array = [0]:x2, [1]:x108
122 btc(array, 35) = -1
123 array = [0]:x2, [1]:x100
124 bts(array, 35) = 0
125 array = [0]:x2, [1]:x108
126 btr(array, 35) = -1
127 array = [0]:x2, [1]:x100
128 bt(array, 1) = -1
129 array = [0]:x2, [1]:x100
130 </pre>
131 */
132 int bts( uint* p, uint bitnum );
133
134
135 /**
136 * Swaps bytes in a 4 byte uint end-to-end, i.e. byte 0 becomes
137 * byte 3, byte 1 becomes byte 2, byte 2 becomes byte 1, byte 3
138 * becomes byte 0.
139 */
140 uint bswap( uint v );
141
142
143 /**
144 * Reads I/O port at port_address.
145 */
146 ubyte inp( uint port_address );
147
148
149 /**
150 * ditto
151 */
152 ushort inpw( uint port_address );
153
154
155 /**
156 * ditto
157 */
158 uint inpl( uint port_address );
159
160
161 /**
162 * Writes and returns value to I/O port at port_address.
163 */
164 ubyte outp( uint port_address, ubyte value );
165
166
167 /**
168 * ditto
169 */
170 ushort outpw( uint port_address, ushort value );
171
172
173 /**
174 * ditto
175 */
176 uint outpl( uint port_address, uint value );