OpenModem/bertos/cfg/macros.h

413 lines
13 KiB
C++

/**
* \file
* <!--
* This file is part of BeRTOS.
*
* Bertos is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* As a special exception, you may use this file as part of a free software
* library without restriction. Specifically, if other files instantiate
* templates or use macros or inline functions from this file, or you compile
* this file and link it with other files to produce an executable, this
* file does not by itself cause the resulting executable to be covered by
* the GNU General Public License. This exception does not however
* invalidate any other reasons why the executable file might be covered by
* the GNU General Public License.
*
* Copyright 2003, 2004 Develer S.r.l. (http://www.develer.com/)
*
* -->
*
* \defgroup macros General purpose macros
* \ingroup core
* \{
*
* \brief Common and handy function macros
*
* \author Bernie Innocenti <bernie@codewiz.org>
* \author Giovanni Bajo <rasky@develer.com>
*/
#ifndef CFG_MACROS_H
#define CFG_MACROS_H
#include <cfg/compiler.h>
/* avr-gcc does not seem to support libstdc++ */
#if defined(__cplusplus) && !CPU_AVR
/* Type-generic macros implemented with template functions. */
#include <algorithm>
template<class T> inline T ABS(T n) { return n >= 0 ? n : -n; }
#define MIN(a,b) std::min(a, b)
#define MAX(a,b) std::max(a, b)
#define SWAP(a,b) std::swap(a, b)
#elif (COMPILER_STATEMENT_EXPRESSIONS && COMPILER_TYPEOF)
/* Type-generic macros implemented with statement expressions. */
#define ABS(n) ({ \
typeof(n) _n = (n); \
(_n < 0) ? -_n : _n; \
})
#define MIN(a,b) ({ \
typeof(a) _a = (a); \
typeof(b) _b = (b); \
ASSERT_TYPE_EQUAL(_a, _b); \
/** \
* The (typeof(_a)) cast in necessary: \
* result type of conditional expressions is \
* *NOT* the type of the value returned but \
* the type that would be produced if _a and _b \
* were mixed in an expression. \
* Even in _a and _b are of the same type, \
* if mixed in an expression the type will be \
* (at least) promoted to int! \
*/ \
((typeof(_a))((_a < _b) ? _a : _b)); \
})
#define MAX(a,b) ({ \
typeof(a) _a = (a); \
typeof(b) _b = (b); \
ASSERT_TYPE_EQUAL(_a, _b); \
/** \
* The (typeof(_a)) cast in necessary: \
* result type of conditional expressions is \
* *NOT* the type of the value returned but \
* the type that would be produced if _a and _b \
* were mixed in an expression. \
* Even in _a and _b are of the same type, \
* if mixed in an expression the type will be \
* (at least) promoted to int! \
*/ \
((typeof(_a))((_a > _b) ? _a : _b)); \
})
#else /* !(COMPILER_STATEMENT_EXPRESSIONS && COMPILER_TYPEOF) */
/* Buggy macros for inferior compilers. */
#define ABS(a) (((a) < 0) ? -(a) : (a))
#define MIN(a,b) (((a) < (b)) ? (a) : (b))
#define MAX(a,b) (((a) > (b)) ? (a) : (b))
#endif /* !(COMPILER_STATEMENT_EXPRESSIONS && COMPILER_TYPEOF) */
/** Align \p value to the next \p align boundary */
#define ALIGN_UP(value, align) (((value) & ((align) - 1)) ? \
(((value) + ((align) - 1)) & ~((align) - 1)) : \
(value))
/** Bound \a x between \a min and \a max. */
#define MINMAX(min,x,max) (MIN(MAX(min, x), max))
#ifdef __cplusplus
/* Use standard implementation from <algorithm> */
#define SWAP(a,b) std::swap(a, b)
#elif COMPILER_TYPEOF
/**
* Type-generic macro to swap \a a with \a b.
*
* \note Arguments are evaluated multiple times.
*/
#define SWAP(a, b) \
do { \
typeof(a) tmp; \
ASSERT_TYPE_EQUAL(a, b); \
tmp = (a); \
(a) = (b); \
(b) = tmp; \
} while (0)
#else /* !COMPILER_TYPEOF */
/* Sub-optimal implementation that only works with integral types. */
#define SWAP(a, b) \
do { \
(a) ^= (b); \
(b) ^= (a); \
(a) ^= (b); \
} while (0)
#endif /* COMPILER_TYPEOF */
/**
* Shuffle the content of \a array that counts \a len elements.
*/
#define SHUFFLE(array, len) \
do { \
int i, j; \
for (i = (len) - 1; i > 0; i--) \
{ \
j = ((i + 1) * (rand() / (RAND_MAX + 1.0))); \
SWAP((array)[i], (array)[j]); \
} \
} while (0)
/**
* Macro to swap \a a with \a b, with explicit type \a T for dumb C89 compilers.
*
* \note Arguments are evaluated multiple times.
*/
#define SWAP_T(a, b, T) \
do { \
T tmp; \
ASSERT_TYPE_IS(a, T); \
ASSERT_TYPE_IS(b, T); \
tmp = (a); \
(a) = (b); \
(b) = tmp; \
} while (0)
/**
* Reverse the bits contained in b (LSB becomes the MSB and so on).
* \note \a b is evaluated twice
*/
#define REVERSE_UINT8(b) \
((uint8_t)((((b) * 0x0802UL & 0x22110UL) | ((b) * 0x8020UL & 0x88440UL)) * 0x10101UL >> 16))
#ifndef BV
/** Convert a bit value to a binary flag. */
#define BV(x) (1<<(x))
#endif
/** Same as BV() but with 32 bit result */
#define BV32(x) ((uint32_t)1<<(x))
/** Same as BV() but with 16 bit result */
#define BV16(x) ((uint16_t)1<<(x))
/** Same as BV() but with 8 bit result */
#define BV8(x) ((uint8_t)1<<(x))
/**
* Perform an integer division rounding the result to the nearest int value.
* \note \a divisor should preferibly be a costant, otherwise this macro generates
* 2 division. Also divisor is evaluated twice.
*/
#define DIV_ROUND(dividend, divisor) (((dividend) + (divisor) / 2) / (divisor))
/**
* Perform an integer division rounding the result to the upper int value.
* \note \a divisor is evaluated twice.
*/
#define DIV_ROUNDUP(dividend, divisor) (((dividend) + (divisor) - 1) / (divisor))
/**
* Perform a multiply between the integer \a a and the float constant \a f.
*
* This macro can be used in order to avoid floating point arithmetics
* in expressions like this:
* \code
* int a, b;
* a = b * 0.5579652750;
* \endcode
*
* This macro rounds the floating point constant to a fraction,
* usign (2 ^ prec) as the denominator.
* For instance, with prec = 8, the constant 0.5579652750 will be rounded to:
* (143 / 256) = 0.55859375
* So, the former code will be transformed to:
* \code
* a = b * 143 / 256;
* \endcode
*
* Since the denominator is a power of 2, we rely on the compiler to optimize
* this to a right shift.
* So, when you have to multiply an integer by a float constant, this macro
* will not use the floating point arithmentics.
* The operation will be converted to a mul + shift, with a huge performance boost.
*
* \note \a f MUST be a constant in order gain performance benefits.
*
* \param a integer you want to multiply
* \param f floating point constant which you want to multply with \a a
* \param prec conversion precision, ranges from 1 to the number of bits in a long.
* The higher, the better the approximation of the float constant will be.
*/
#define INT_MULT(a, f, prec) (((a) * (long)((f) * (1 << (prec)) + 0.5)) >> (prec))
/** Round up \a x to an even multiple of the 2's power \a pad. */
#define ROUND_UP2(x, pad) (((x) + ((pad) - 1)) & ~((pad) - 1))
/**
* \name Integer round macros.
*
* Round \a x to a multiple of \a base.
* \note If \a x is signed these macros generate a lot of code.
* \{
*/
#define ROUND_DOWN(x, base) ( (x) - ((x) % (base)) )
#define ROUND_UP(x, base) ( ((x) + (base) - 1) - (((x) + (base) - 1) % (base)) )
#define ROUND_NEAREST(x, base) ( ((x) + (base) / 2) - (((x) + (base) / 2) % (base)) )
/* \} */
/** Check if \a x is an integer power of 2. */
#define IS_POW2(x) (!(bool)((x) & ((x)-1)))
/** Calculate a compile-time log2 for a uint8_t */
#define UINT8_LOG2(x) \
((x) < 2 ? 0 : \
((x) < 4 ? 1 : \
((x) < 8 ? 2 : \
((x) < 16 ? 3 : \
((x) < 32 ? 4 : \
((x) < 64 ? 5 : \
((x) < 128 ? 6 : 7)))))))
/** Calculate a compile-time log2 for a uint16_t */
#define UINT16_LOG2(x) \
((x < 256) ? UINT8_LOG2(x) : UINT8_LOG2((x) >> 8) + 8)
/** Calculate a compile-time log2 for a uint32_t */
#define UINT32_LOG2(x) \
((x < 65536UL) ? UINT16_LOG2(x) : UINT16_LOG2((x) >> 16) + 16)
#if COMPILER_VARIADIC_MACROS
/** Count the number of arguments (up to 16). */
#define PP_COUNT(...) \
PP_COUNT__(__VA_ARGS__,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,0)
#define PP_COUNT__(a0,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,count,...) \
count
#endif
#if COMPILER_VARIADIC_MACROS
/**
* \def BIT_CHANGE(reg, (mask, value), ...)
*
* This macro allows for efficient and compact bit toggling in a hardware
* register. It is meant to replace hand-coded cruft which toggles bits
* in sequence.
*
* It is possible to specify an unlimited pair of (mask, value) parameters.
* For instance:
*
* \code
* void set_timer(bool start)
* {
* BIT_CHANGE(REG_CTRL_TIMER,
* (TIMER_MODE, MODE_COUNT),
* (OVL_IRQ, 1),
* (CMP_IRQ, 1),
* (START, start)
* );
* }
* \endcode
*
* The macro expansion will be roughly the following:
*
* \code
* REG_CTRL_TIMER = (REG_CTRL_TIMER & ~(TIMER_MODE|OVL_IRQ|CMP_IRQ|START)
* | (MODE_COUNT|OVL_IRQ|CMP_IRQ|(start ? START : 0));
* \endcode
*
* It is up to the compiler to produce the optimal code. We checked that GCC produces
* the best code in most cases. We preferred this expansion over the use of a block
* with a local variable because CodeWarrior 6.1 was not able to remove completely the
* allocation of the local from the stack.
*
* \note This macro is available only in C99 because it makes use of variadic macros.
* It would be possible to make up an implementation with a slightly different syntax
* for use with C90 compilers, through Boost Preprocessor.
*/
/**
* \def BIT_CHANGE_BV(reg, (bit, value), ...)
*
* Similar to BIT_CHANGE(), but get bits instead of masks (and applies BV() to convert
* them to masks).
*/
#define BIT_EXTRACT_FLAG_0(bit, value) bit
#define BIT_EXTRACT_FLAG_1(bit, value) BV(bit)
#define BIT_EXTRACT_VALUE__(bit, value) value
#define BIT_MASK_SINGLE__(use_bv, index, max, arg) \
((index < max) ? (PP_CAT(BIT_EXTRACT_FLAG_, use_bv) arg) : 0) \
/* */
#define BIT_MASK_IF_SINGLE__(use_bv, index, max, arg) \
(((index < max) && (BIT_EXTRACT_VALUE__ arg)) ? (PP_CAT(BIT_EXTRACT_FLAG_, use_bv) arg) : 0) \
/* */
#define BIT_ITER__2(macro, use_bv, max, a0,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15, ...) \
(macro(use_bv, 0, max, a0) | \
macro(use_bv, 1, max, a1) | \
macro(use_bv, 2, max, a2) | \
macro(use_bv, 3, max, a3) | \
macro(use_bv, 4, max, a4) | \
macro(use_bv, 5, max, a5) | \
macro(use_bv, 6, max, a6) | \
macro(use_bv, 7, max, a7) | \
macro(use_bv, 8, max, a8) | \
macro(use_bv, 9, max, a9) | \
macro(use_bv, 10, max, a10) | \
macro(use_bv, 11, max, a11) | \
macro(use_bv, 12, max, a12) | \
macro(use_bv, 13, max, a13) | \
macro(use_bv, 14, max, a14) | \
macro(use_bv, 15, max, a15)) \
/* */
#define BIT_ITER__(macro, use_bv, ...) \
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)) \
/* */
#define BIT_MASKS__(use_bv, ...) \
BIT_ITER__(BIT_MASK_SINGLE__, use_bv, __VA_ARGS__)
/* */
#define BIT_MASKS_CONDITIONAL__(use_bv, ...) \
BIT_ITER__(BIT_MASK_IF_SINGLE__, use_bv, __VA_ARGS__)
/* */
#define BIT_CHANGE__(reg, use_bv, ...) \
((reg) = ((reg) & ~BIT_MASKS__(use_bv, __VA_ARGS__)) | BIT_MASKS_CONDITIONAL__(use_bv, __VA_ARGS__)) \
/* */
#define BIT_CHANGE(reg, ...) BIT_CHANGE__(reg, 0, __VA_ARGS__)
#define BIT_CHANGE_BV(reg, ...) BIT_CHANGE__(reg, 1, __VA_ARGS__)
#endif /* COMPILER_VARIADIC_MACROS */
/**
* Macro for rotating bit left or right.
* \{
*/
#define ROTR(var, rot) (((var) >> (rot)) | ((var) << ((sizeof(var) * 8) - (rot))))
#define ROTL(var, rot) (((var) << (rot)) | ((var) >> ((sizeof(var) * 8) - (rot))))
/*\}*/
/**
* Make an id from 4 letters, useful for
* file formats and kfile ids.
*/
#define MAKE_ID(a,b,c,d) \
( ((uint32_t)(a) << 24) \
| ((uint32_t)(b) << 16) \
| ((uint32_t)(c) << 8) \
| ((uint32_t)(d) << 0) )
/**
* Type for id generated by MAKE_ID().
*/
typedef uint32_t id_t;
/**
* Check if a pointer is aligned to a certain power-of-2 size
*/
INLINE bool is_aligned(const void *addr, size_t size)
{
return ((size_t)addr & (size - 1)) == 0;
}
/** \} */ //defgroup macros
#endif /* MACROS_H */