macros.h

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#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); \
 \
        ((typeof(_a))((_a < _b) ? _a : _b)); \
    })
    #define MAX(a,b) ({ \
        typeof(a) _a = (a); \
        typeof(b) _b = (b); \
        ASSERT_TYPE_EQUAL(_a, _b); \
 \
        ((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) */

#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

    #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 */

#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)


#ifndef BV

    #define BV(x)  (1<<(x))
#endif

#define BV32(x)  ((uint32_t)1<<(x))

#define BV16(x)  ((uint16_t)1<<(x))

#define BV8(x)  ((uint8_t)1<<(x))

#define DIV_ROUND(dividend, divisor)  (((dividend) + (divisor) / 2) / (divisor))

#define ROUND_UP2(x, pad) (((x) + ((pad) - 1)) & ~((pad) - 1))

/* OBSOLETE */
#define ROUND2 ROUND_UP2

#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)) )
/* \} */

#define IS_POW2(x)     (!(bool)((x) & ((x)-1)))

#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)))))))

#define UINT16_LOG2(x) \
    ((x < 256) ? UINT8_LOG2(x) : UINT8_LOG2((x) >> 8) + 8)

#define UINT32_LOG2(x) \
    ((x < 65536UL) ? UINT16_LOG2(x) : UINT16_LOG2((x) >> 16) + 16)

#if COMPILER_VARIADIC_MACROS

    #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

    #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 */

#define ROTR(var, rot) (((var) >> (rot)) | ((var) << ((sizeof(var) * 8) - (rot))))
#define ROTL(var, rot) (((var) << (rot)) | ((var) >> ((sizeof(var) * 8) - (rot))))
/*\}*/

#define MAKE_ID(a,b,c,d) \
    ( ((uint32_t)(a) << 24) \
    | ((uint32_t)(b) << 16) \
    | ((uint32_t)(c) <<  8) \
    | ((uint32_t)(d) <<  0) )

typedef uint32_t id_t;

#endif /* MACROS_H */