4 * Copyright 2003, 2004 Develer S.r.l. (http://www.develer.com/)
5 * This file is part of DevLib - See devlib/README for information.
10 * \author Bernardo Innocenti <bernie@develer.com>
11 * \author Giovanni Bajo <rasky@develer.com>
13 * \brief Common and handy function macros
18 * Revision 1.2 2004/08/24 13:32:14 bernie
19 * PP_CAT(), PP_STRINGIZE(): Move back to compiler.h to break circular dependency between cpu.h/compiler.h/macros.h;
20 * offsetof(), countof(): Move back to compiler.h to avoid including macros.h almost everywhere;
22 * Rename header guards;
23 * Don't include arch_config.h in compiler.h as it's not needed there.
25 * Revision 1.1 2004/08/14 19:37:57 rasky
26 * Merge da SC: macros.h, pool.h, BIT_CHANGE, nome dei processi, etc.
28 * Revision 1.4 2004/08/14 18:36:50 rasky
29 * Doxygen fix e un livello di parentesi aggiuntivi per la macro
31 * Revision 1.3 2004/08/12 20:01:32 rasky
32 * Aggiunte macro BIT_CHANGE e BIT_CHANGE_BV
34 * Revision 1.2 2004/08/10 21:36:14 rasky
35 * Aggiunto include macros.h dove serve
36 * Aggiunta dipendenza da compiler.h in macros.h
38 * Revision 1.1 2004/08/10 21:30:00 rasky
39 * Estratte le funzioni macro in macros.h
49 #define ABS(a) (((a) < 0) ? -(a) : (a))
50 #define MIN(a,b) (((a) < (b)) ? (a) : (b))
51 #define MAX(a,b) (((a) > (b)) ? (a) : (b))
54 /*! Convert a bit value to a binary flag */
55 #define BV(x) (1<<(x))
58 /*! Round up \a x to an even multiple of the 2's power \a pad */
59 #define ROUND2(x, pad) (((x) + ((pad) - 1)) & ~((pad) - 1))
61 //! Check if \a x is an integer power of 2
62 #define IS_POW2(x) (!(bool)((x) & ((x)-1)))
64 /*! Calculate a compile-time log2 for a uint8_t */
65 #define UINT8_LOG2(x) \
72 ((x) < 128 ? 6 : 7)))))))
74 /*! Calculate a compile-time log2 for a uint16_t */
75 #define UINT16_LOG2(x) \
76 ((x < 256) ? UINT8_LOG2(x) : UINT8_LOG2((x) >> 8) + 8)
78 /*! Calculate a compile-time log2 for a uint32_t */
79 #define UINT32_LOG2(x) \
80 ((x < 65536UL) ? UINT16_LOG2(x) : UINT16_LOG2((x) >> 16) + 16)
83 /*! Count the number of arguments (up to 16) */
84 #define PP_COUNT(...) \
85 PP_COUNT__(__VA_ARGS__,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,0)
86 #define PP_COUNT__(a0,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,count,...) \
90 /*! Issue a compilation error if the \a condition is false */
91 #define STATIC_ASSERT(condition) \
92 extern char CT_ASSERT___[(condition) ? 1 : -1]
97 * \def BIT_CHANGE(reg, (mask, value), ...)
99 * This macro allows for efficient and compact bit toggling in a hardware
100 * register. It is meant to replace hand-coded cruft which toggles bits
103 * It is possible to specify an unlimited pair of (mask, value) parameters.
107 * void set_timer(bool start)
109 * BIT_CHANGE(REG_CTRL_TIMER,
110 * (TIMER_MODE, MODE_COUNT),
118 * The macro expansion will be roughly the following:
121 * REG_CTRL_TIMER = (REG_CTRL_TIMER & ~(TIMER_MODE|OVL_IRQ|CMP_IRQ|START)
122 * | (MODE_COUNT|OVL_IRQ|CMP_IRQ|(start ? START : 0));
125 * It is up to the compiler to produce the optimal code. We checked that GCC produces
126 * the best code in most cases. We preferred this expansion over the use of a block
127 * with a local variable because CodeWarrior 6.1 was not able to remove completely the
128 * allocation of the local from the stack.
130 * \note This macro is available only in C99 because it makes use of variadic macros.
131 * It would be possible to make up an implementation with a slightly different syntax
132 * for use with C90 compilers, through Boost Preprocessor.
137 * \def BIT_CHANGE_BV(reg, (bit, value), ...)
139 * Similar to BIT_CHANGE(), but get bits instead of masks (and applies BV() to convert
144 #define BIT_EXTRACT_FLAG_0(bit, value) bit
145 #define BIT_EXTRACT_FLAG_1(bit, value) BV(bit)
146 #define BIT_EXTRACT_VALUE__(bit, value) value
148 #define BIT_MASK_SINGLE__(use_bv, index, max, arg) \
149 ((index < max) ? (PP_CAT(BIT_EXTRACT_FLAG_, use_bv) arg) : 0) \
152 #define BIT_MASK_IF_SINGLE__(use_bv, index, max, arg) \
153 (((index < max) && (BIT_EXTRACT_VALUE__ arg)) ? (PP_CAT(BIT_EXTRACT_FLAG_, use_bv) arg) : 0) \
156 #define BIT_ITER__2(macro, use_bv, max, a0,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15, ...) \
157 (macro(use_bv, 0, max, a0) | \
158 macro(use_bv, 1, max, a1) | \
159 macro(use_bv, 2, max, a2) | \
160 macro(use_bv, 3, max, a3) | \
161 macro(use_bv, 4, max, a4) | \
162 macro(use_bv, 5, max, a5) | \
163 macro(use_bv, 6, max, a6) | \
164 macro(use_bv, 7, max, a7) | \
165 macro(use_bv, 8, max, a8) | \
166 macro(use_bv, 9, max, a9) | \
167 macro(use_bv, 10, max, a10) | \
168 macro(use_bv, 11, max, a11) | \
169 macro(use_bv, 12, max, a12) | \
170 macro(use_bv, 13, max, a13) | \
171 macro(use_bv, 14, max, a14) | \
172 macro(use_bv, 15, max, a15)) \
175 #define BIT_ITER__(macro, use_bv, ...) \
176 BIT_ITER__2(macro, use_bv, PP_COUNT(__VA_ARGS__), __VA_ARGS__, (0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1)) \
179 #define BIT_MASKS__(use_bv, ...) \
180 BIT_ITER__(BIT_MASK_SINGLE__, use_bv, __VA_ARGS__)
183 #define BIT_MASKS_CONDITIONAL__(use_bv, ...) \
184 BIT_ITER__(BIT_MASK_IF_SINGLE__, use_bv, __VA_ARGS__)
187 #define BIT_CHANGE__(reg, use_bv, ...) \
188 ((reg) = ((reg) & ~BIT_MASKS__(use_bv, __VA_ARGS__)) | BIT_MASKS_CONDITIONAL__(use_bv, __VA_ARGS__)) \
191 #define BIT_CHANGE(reg, ...) BIT_CHANGE__(reg, 0, __VA_ARGS__)
192 #define BIT_CHANGE_BV(reg, ...) BIT_CHANGE__(reg, 1, __VA_ARGS__)
194 #endif /* COMPILER_C99 */
196 #endif /* MACROS_H */