1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/jitcraft/Utility.h	Mon Jun 25 02:57:28 2012 -0700
     1.3 @@ -0,0 +1,105 @@
     1.4 +/*
     1.5 + * Copyright (C) 2012 David Anderson
     1.6 + *
     1.7 + * This file is part of JITCraft.
     1.8 + *
     1.9 + * JITCraft is free software: you can redistribute it and/or modify it under
    1.10 + * the terms of the GNU General Public License as published by the Free
    1.11 + * Software Foundation, either version 3 of the License, or (at your option)
    1.12 + * any later version.
    1.13 + * 
    1.14 + * Foobar is distributed in the hope that it will be useful, but WITHOUT ANY
    1.15 + * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
    1.16 + * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
    1.17 + *
    1.18 + * You should have received a copy of the GNU General Public License along with
    1.19 + * JITCraft. If not, see http://www.gnu.org/licenses/.
    1.20 + */
    1.21 +#ifndef _include_jitcraft_utility_h_
    1.22 +#define _include_jitcraft_utility_h_
    1.23 +
    1.24 +#include <assert.h>
    1.25 +#include <intrin.h>
    1.26 +
    1.27 +namespace jc {
    1.28 +
    1.29 +static const size_t kMallocAlignment = sizeof(void *) * 2;
    1.30 +
    1.31 +template <typename T>
    1.32 +class AutoVec
    1.33 +{
    1.34 +    T *t_;
    1.35 +
    1.36 +  public:
    1.37 +    AutoVec()
    1.38 +      : t_(NULL)
    1.39 +    {
    1.40 +    }
    1.41 +    AutoVec(T *t)
    1.42 +      : t_(t)
    1.43 +    {
    1.44 +    }
    1.45 +    ~AutoVec() {
    1.46 +        delete [] t_;
    1.47 +    }
    1.48 +    operator T *() {
    1.49 +        return t_;
    1.50 +    }
    1.51 +    void operator =(T *t) {
    1.52 +        if (t_)
    1.53 +            delete [] t_;
    1.54 +        t_ = t;
    1.55 +    }
    1.56 +};
    1.57 +
    1.58 +static inline size_t
    1.59 +Log2(size_t number)
    1.60 +{
    1.61 +    assert(number != 0);
    1.62 +
    1.63 +    unsigned long rval;
    1.64 +    _BitScanReverse(&rval, number);
    1.65 +    return rval;
    1.66 +}
    1.67 +
    1.68 +static inline bool
    1.69 +IsPowerOfTwo(size_t value)
    1.70 +{
    1.71 +    if (value == 0)
    1.72 +        return false;
    1.73 +    return !(value & (value - 1));
    1.74 +}
    1.75 +
    1.76 +static inline size_t
    1.77 +Align(size_t count, size_t alignment)
    1.78 +{
    1.79 +    assert(IsPowerOfTwo(alignment));
    1.80 +    return count + (alignment - (count % alignment)) % alignment;
    1.81 +}
    1.82 +
    1.83 +static inline bool
    1.84 +IsUint32AddSafe(unsigned a, unsigned b)
    1.85 +{
    1.86 +    unsigned log2_a = Log2(a);
    1.87 +    unsigned log2_b = Log2(b);
    1.88 +    return (log2_a < sizeof(unsigned) * 8) &&
    1.89 +           (log2_b < sizeof(unsigned) * 8);
    1.90 +}
    1.91 +
    1.92 +static inline bool
    1.93 +IsUint32MultiplySafe(unsigned a, unsigned b)
    1.94 +{
    1.95 +    if (a <= 1 || b <= 1)
    1.96 +        return true;
    1.97 +
    1.98 +    unsigned log2_a = Log2(a);
    1.99 +    unsigned log2_b = Log2(b);
   1.100 +    return log2_a + log2_b <= sizeof(unsigned) * 8;
   1.101 +}
   1.102 +
   1.103 +#define ARRAY_LENGTH(array) (sizeof(array) / sizeof(array[0]))
   1.104 +#define STATIC_ASSERT(cond) extern int static_assert_f(int a[(cond) ? 1 : -1])
   1.105 +
   1.106 +}
   1.107 +
   1.108 +#endif // _include_jitcraft_utility_h_