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))
67 #define STRUCT_MARK(mark) u8 mark[0]
68 #define STRUCT_MARK_PTR(v, f) &(v)->f
70 /* Stride in bytes between struct array elements. */
71 #define STRUCT_STRIDE_OF(t,f) \
72 ( ((uword) & (((t *) 0)[1].f)) \
73 - ((uword) & (((t *) 0)[0].f)))
75 #define STRUCT_OFFSET_OF_VAR(v,f) ((uword) (&(v)->f) - (uword) (v))
77 /* Used to pack structure elements. */
78 #define CLIB_PACKED(x) x __attribute__ ((packed))
79 #define CLIB_UNUSED(x) x __attribute__ ((unused))
81 /* Make a string from the macro's argument */
82 #define CLIB_STRING_MACRO(x) #x
84 #define __clib_unused __attribute__ ((unused))
85 #define __clib_weak __attribute__ ((weak))
86 #define __clib_packed __attribute__ ((packed))
87 #define __clib_constructor __attribute__ ((constructor))
89 #define never_inline __attribute__ ((__noinline__))
92 #define always_inline static inline
93 #define static_always_inline static inline
95 #define always_inline static inline __attribute__ ((__always_inline__))
96 #define static_always_inline static inline __attribute__ ((__always_inline__))
100 /* Reserved (unused) structure element with address offset between
102 #define CLIB_PAD_FROM_TO(from,to) u8 pad_##from[(to) - (from)]
104 /* Hints to compiler about hot/cold code. */
105 #define PREDICT_FALSE(x) __builtin_expect((x),0)
106 #define PREDICT_TRUE(x) __builtin_expect((x),1)
108 /* Full memory barrier (read and write). */
109 #define CLIB_MEMORY_BARRIER() __sync_synchronize ()
112 #define CLIB_MEMORY_STORE_BARRIER() __builtin_ia32_sfence ()
114 #define CLIB_MEMORY_STORE_BARRIER() __sync_synchronize ()
117 /* Arranges for function to be called before main. */
118 #define INIT_FUNCTION(decl) \
119 decl __attribute ((constructor)); \
122 /* Arranges for function to be called before exit. */
123 #define EXIT_FUNCTION(decl) \
124 decl __attribute ((destructor)); \
127 /* Use __builtin_clz if available. */
129 #include <features.h>
130 #if __GNUC_PREREQ(3, 4)
132 #define count_leading_zeros(count,x) count = __builtin_clzll (x)
133 #define count_trailing_zeros(count,x) count = __builtin_ctzll (x)
135 #define count_leading_zeros(count,x) count = __builtin_clzl (x)
136 #define count_trailing_zeros(count,x) count = __builtin_ctzl (x)
141 #ifndef count_leading_zeros
143 /* Misc. integer arithmetic functions. */
145 #define count_leading_zeros(count, x) \
148 __asm__ ("bsrl %1,%0" \
149 : "=r" (_clz) : "rm" ((word) (x)));\
150 (count) = _clz ^ 31; \
153 #define count_trailing_zeros(count, x) \
154 __asm__ ("bsfl %1,%0" : "=r" (count) : "rm" ((word)(x)))
157 #if defined (__alpha__) && defined (HAVE_CIX)
158 #define count_leading_zeros(count, x) \
159 __asm__ ("ctlz %1,%0" \
160 : "=r" ((word) (count)) \
162 #define count_trailing_zeros(count, x) \
163 __asm__ ("cttz %1,%0" \
164 : "=r" ((word) (count)) \
166 #endif /* alpha && HAVE_CIX */
170 /* Select between 32/64 opcodes. */
172 #define count_leading_zeros(_count, _x) \
173 __asm__ ("clz %[count],%[x]" \
174 : [count] "=r" ((word) (_count)) \
175 : [x] "r" ((word) (_x)))
177 #define count_leading_zeros(_count, _x) \
178 __asm__ ("dclz %[count],%[x]" \
179 : [count] "=r" ((word) (_count)) \
180 : [x] "r" ((word) (_x)))
183 #endif /* __mips >= 4 */
185 #endif /* count_leading_zeros */
187 #if defined (count_leading_zeros)
192 count_leading_zeros (n, x);
193 return BITS (uword) - n - 1;
199 uword a = x, b = BITS (uword) / 2, c = 0, r = 0;
201 /* Reduce x to 4 bit result. */
210 if (BITS (uword) > 32)
217 /* Do table lookup on 4 bit partial. */
218 if (BITS (uword) > 32)
220 const u64 table = 0x3333333322221104LL;
221 uword t = (table >> (4 * a)) & 0xf;
222 r = t < 4 ? r + t : ~0;
226 const u32 table = 0x22221104;
227 uword t = (a & 8) ? 3 : ((table >> (4 * a)) & 0xf);
228 r = t < 4 ? r + t : ~0;
238 uword l = min_log2 (x);
239 if (x > ((uword) 1 << l))
247 if (BITS (uword) == 64)
267 return ((uword) 1 << x) - (uword) 1;
273 word y = (word) 1 << min_log2 (x);
282 return 0 == (x & (x - 1));
286 round_pow2 (uword x, uword pow2)
288 return (x + pow2 - 1) & ~(pow2 - 1);
292 round_pow2_u64 (u64 x, u64 pow2)
294 return (x + pow2 - 1) & ~(pow2 - 1);
304 log2_first_set (uword x)
307 #ifdef count_trailing_zeros
308 count_trailing_zeros (result, x);
310 result = min_log2 (first_set (x));
316 flt_round_down (f64 x)
322 flt_round_nearest (f64 x)
324 return (word) (x + .5);
328 flt_round_to_multiple (f64 x, f64 f)
330 return f * flt_round_nearest (x / f);
333 #define clib_max(x,y) \
335 __typeof__ (x) _x = (x); \
336 __typeof__ (y) _y = (y); \
340 #define clib_min(x,y) \
342 __typeof__ (x) _x = (x); \
343 __typeof__ (y) _y = (y); \
347 #define clib_abs(x) \
349 __typeof__ (x) _x = (x); \
353 /* Standard standalone-only function declarations. */
355 void clib_standalone_init (void *memory, uword memory_bytes);
357 void qsort (void *base, uword n, uword size,
358 int (*)(const void *, const void *));
361 /* Stack backtrace. */
363 clib_backtrace (uword * callers, uword max_callers, uword n_frames_to_skip);
365 #endif /* included_clib_h */
368 * fd.io coding-style-patch-verification: ON
371 * eval: (c-set-style "gnu")