2 * Copyright (c) 2015 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 Copyright (c) 2001, 2002, 2003 Eliot Dresselhaus
18 Permission is hereby granted, free of charge, to any person obtaining
19 a copy of this software and associated documentation files (the
20 "Software"), to deal in the Software without restriction, including
21 without limitation the rights to use, copy, modify, merge, publish,
22 distribute, sublicense, and/or sell copies of the Software, and to
23 permit persons to whom the Software is furnished to do so, subject to
24 the following conditions:
26 The above copyright notice and this permission notice shall be
27 included in all copies or substantial portions of the Software.
29 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
30 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
31 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
32 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
33 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
34 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
35 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
38 #ifndef included_clib_h
39 #define included_clib_h
41 /* Standalone means to not assume we are running on a Unix box. */
42 #if ! defined (CLIB_STANDALONE) && ! defined (CLIB_LINUX_KERNEL)
46 #include <vppinfra/types.h>
48 /* Global DEBUG flag. Setting this to 1 or 0 turns off
49 ASSERT (see vppinfra/error.h) & other debugging code. */
55 #define NULL ((void *) 0)
58 #define BITS(x) (8*sizeof(x))
59 #define ARRAY_LEN(x) (sizeof (x)/sizeof (x[0]))
61 #define _STRUCT_FIELD(t,f) (((t *) 0)->f)
62 #define STRUCT_OFFSET_OF(t,f) ((uword) & _STRUCT_FIELD (t, f))
63 #define STRUCT_BIT_OFFSET_OF(t,f) (BITS(u8) * (uword) & _STRUCT_FIELD (t, f))
64 #define STRUCT_SIZE_OF(t,f) (sizeof (_STRUCT_FIELD (t, f)))
65 #define STRUCT_BITS_OF(t,f) (BITS (_STRUCT_FIELD (t, f)))
66 #define STRUCT_ARRAY_LEN(t,f) ARRAY_LEN (_STRUCT_FIELD (t, f))
68 /* Stride in bytes between struct array elements. */
69 #define STRUCT_STRIDE_OF(t,f) \
70 ( ((uword) & (((t *) 0)[1].f)) \
71 - ((uword) & (((t *) 0)[0].f)))
73 #define STRUCT_OFFSET_OF_VAR(v,f) ((uword) (&(v)->f) - (uword) (v))
75 /* Used to pack structure elements. */
76 #define CLIB_PACKED(x) x __attribute__ ((packed))
77 #define CLIB_UNUSED(x) x __attribute__ ((unused))
79 #define never_inline __attribute__ ((__noinline__))
82 #define always_inline static inline
83 #define static_always_inline static inline
85 #define always_inline static inline __attribute__ ((__always_inline__))
86 #define static_always_inline static inline __attribute__ ((__always_inline__))
90 /* Reserved (unused) structure element with address offset between
92 #define CLIB_PAD_FROM_TO(from,to) u8 pad_##from[(to) - (from)]
94 /* Hints to compiler about hot/cold code. */
95 #define PREDICT_FALSE(x) __builtin_expect((x),0)
96 #define PREDICT_TRUE(x) __builtin_expect((x),1)
98 /* Full memory barrier (read and write). */
99 #define CLIB_MEMORY_BARRIER() __sync_synchronize ()
101 /* Arranges for function to be called before main. */
102 #define INIT_FUNCTION(decl) \
103 decl __attribute ((constructor)); \
106 /* Arranges for function to be called before exit. */
107 #define EXIT_FUNCTION(decl) \
108 decl __attribute ((destructor)); \
111 /* Use __builtin_clz if available. */
113 #include <features.h>
114 #if __GNUC_PREREQ(3, 4)
116 #define count_leading_zeros(count,x) count = __builtin_clzll (x)
117 #define count_trailing_zeros(count,x) count = __builtin_ctzll (x)
119 #define count_leading_zeros(count,x) count = __builtin_clzl (x)
120 #define count_trailing_zeros(count,x) count = __builtin_ctzl (x)
125 #ifndef count_leading_zeros
127 /* Misc. integer arithmetic functions. */
129 #define count_leading_zeros(count, x) \
132 __asm__ ("bsrl %1,%0" \
133 : "=r" (_clz) : "rm" ((word) (x)));\
134 (count) = _clz ^ 31; \
137 #define count_trailing_zeros(count, x) \
138 __asm__ ("bsfl %1,%0" : "=r" (count) : "rm" ((word)(x)))
141 #if defined (__alpha__) && defined (HAVE_CIX)
142 #define count_leading_zeros(count, x) \
143 __asm__ ("ctlz %1,%0" \
144 : "=r" ((word) (count)) \
146 #define count_trailing_zeros(count, x) \
147 __asm__ ("cttz %1,%0" \
148 : "=r" ((word) (count)) \
150 #endif /* alpha && HAVE_CIX */
154 /* Select between 32/64 opcodes. */
156 #define count_leading_zeros(_count, _x) \
157 __asm__ ("clz %[count],%[x]" \
158 : [count] "=r" ((word) (_count)) \
159 : [x] "r" ((word) (_x)))
161 #define count_leading_zeros(_count, _x) \
162 __asm__ ("dclz %[count],%[x]" \
163 : [count] "=r" ((word) (_count)) \
164 : [x] "r" ((word) (_x)))
167 #endif /* __mips >= 4 */
169 #endif /* count_leading_zeros */
171 #if defined (count_leading_zeros)
172 always_inline uword min_log2 (uword x)
175 count_leading_zeros (n, x);
176 return BITS (uword) - n - 1;
179 always_inline uword min_log2 (uword x)
181 uword a = x, b = BITS(uword)/2, c = 0, r = 0;
183 /* Reduce x to 4 bit result. */
192 if (BITS (uword) > 32) _;
196 /* Do table lookup on 4 bit partial. */
197 if (BITS (uword) > 32)
199 const u64 table = 0x3333333322221104LL;
200 uword t = (table >> (4*a)) & 0xf;
201 r = t < 4 ? r + t : ~0;
205 const u32 table = 0x22221104;
206 uword t = (a & 8) ? 3 : ((table >> (4*a)) & 0xf);
207 r = t < 4 ? r + t : ~0;
214 always_inline uword max_log2 (uword x)
216 uword l = min_log2 (x);
217 if (x > ((uword) 1 << l))
222 always_inline u64 min_log2_u64 (u64 x)
224 if (BITS (uword) == 64)
240 always_inline uword pow2_mask (uword x)
241 { return ((uword) 1 << x) - (uword) 1; }
243 always_inline uword max_pow2 (uword x)
245 word y = (word) 1 << min_log2 (x);
250 always_inline uword is_pow2 (uword x)
251 { return 0 == (x & (x - 1)); }
253 always_inline uword round_pow2 (uword x, uword pow2)
255 return (x + pow2 - 1) &~ (pow2 - 1);
258 always_inline u64 round_pow2_u64 (u64 x, u64 pow2)
260 return (x + pow2 - 1) &~ (pow2 - 1);
263 always_inline uword first_set (uword x)
266 always_inline uword log2_first_set (uword x)
269 #ifdef count_trailing_zeros
270 count_trailing_zeros (result, x);
272 result = min_log2 (first_set (x));
277 always_inline f64 flt_round_down (f64 x)
280 always_inline word flt_round_nearest (f64 x)
281 { return (word) (x + .5); }
283 always_inline f64 flt_round_to_multiple (f64 x, f64 f)
284 { return f * flt_round_nearest (x / f); }
286 #define clib_max(x,y) \
288 __typeof__ (x) _x = (x); \
289 __typeof__ (y) _y = (y); \
293 #define clib_min(x,y) \
295 __typeof__ (x) _x = (x); \
296 __typeof__ (y) _y = (y); \
300 #define clib_abs(x) \
302 __typeof__ (x) _x = (x); \
306 /* Standard standalone-only function declarations. */
308 void clib_standalone_init (void * memory, uword memory_bytes);
310 void qsort (void * base, uword n, uword size,
311 int (*) (const void *, const void *));
314 /* Stack backtrace. */
316 clib_backtrace (uword * callers,
318 uword n_frames_to_skip);
320 #endif /* included_clib_h */