include/qemu/int128.h

   1 #ifndef INT128_H
   2 #define INT128_H
   3
   4 typedef struct Int128 Int128;
   5
   6 struct Int128 {
   7     uint64_t lo;
   8     int64_t hi;
   9 };
  10
  11 static inline Int128 int128_make64(uint64_t a)
  12 {
  13     return (Int128) { a, 0 };
  14 }
  15
  16 static inline uint64_t int128_get64(Int128 a)
  17 {
  18     assert(!a.hi);
  19     return a.lo;
  20 }
  21
  22 static inline Int128 int128_zero(void)
  23 {
  24     return int128_make64(0);
  25 }
  26
  27 static inline Int128 int128_one(void)
  28 {
  29     return int128_make64(1);
  30 }
  31
  32 static inline Int128 int128_2_64(void)
  33 {
  34     return (Int128) { 0, 1 };
  35 }
  36
  37 static inline Int128 int128_and(Int128 a, Int128 b)
  38 {
  39     return (Int128) { a.lo & b.lo, a.hi & b.hi };
  40 }
  41
  42 static inline Int128 int128_rshift(Int128 a, int n)
  43 {
  44     int64_t h;
  45     if (!n) {
  46         return a;
  47     }
  48     h = a.hi >> (n & 63);
  49     if (n >= 64) {
  50         return (Int128) { h, h >> 63 };
  51     } else {
  52         return (Int128) { (a.lo >> n) | (a.hi << (64 - n)), h };
  53     }
  54 }
  55
  56 static inline Int128 int128_add(Int128 a, Int128 b)
  57 {
  58     Int128 r = { a.lo + b.lo, a.hi + b.hi };
  59     r.hi += (r.lo < a.lo) || (r.lo < b.lo);
  60     return r;
  61 }
  62
  63 static inline Int128 int128_neg(Int128 a)
  64 {
  65     a.lo = ~a.lo;
  66     a.hi = ~a.hi;
  67     return int128_add(a, int128_one());
  68 }
  69
  70 static inline Int128 int128_sub(Int128 a, Int128 b)
  71 {
  72     return int128_add(a, int128_neg(b));
  73 }
  74
  75 static inline bool int128_nonneg(Int128 a)
  76 {
  77     return a.hi >= 0;
  78 }
  79
  80 static inline bool int128_eq(Int128 a, Int128 b)
  81 {
  82     return a.lo == b.lo && a.hi == b.hi;
  83 }
  84
  85 static inline bool int128_ne(Int128 a, Int128 b)
  86 {
  87     return !int128_eq(a, b);
  88 }
  89
  90 static inline bool int128_ge(Int128 a, Int128 b)
  91 {
  92     return int128_nonneg(int128_sub(a, b));
  93 }
  94
  95 static inline bool int128_lt(Int128 a, Int128 b)
  96 {
  97     return !int128_ge(a, b);
  98 }
  99
 100 static inline bool int128_le(Int128 a, Int128 b)
 101 {
 102     return int128_ge(b, a);
 103 }
 104
 105 static inline bool int128_gt(Int128 a, Int128 b)
 106 {
 107     return !int128_le(a, b);
 108 }
 109
 110 static inline bool int128_nz(Int128 a)
 111 {
 112     return a.lo || a.hi;
 113 }
 114
 115 static inline Int128 int128_min(Int128 a, Int128 b)
 116 {
 117     return int128_le(a, b) ? a : b;
 118 }
 119
 120 static inline Int128 int128_max(Int128 a, Int128 b)
 121 {
 122     return int128_ge(a, b) ? a : b;
 123 }
 124
 125 static inline void int128_addto(Int128 *a, Int128 b)
 126 {
 127     *a = int128_add(*a, b);
 128 }
 129
 130 static inline void int128_subfrom(Int128 *a, Int128 b)
 131 {
 132     *a = int128_sub(*a, b);
 133 }
 134
 135 #endif