Added visual studio _umul128() declaration in crandom.h

1 files changed, 9 insertions, 8 deletions

diff --git a/stc/crandom.h b/stc/crandom.h
index 1e3b2107..a3d0b77c 100644
--- a/stc/crandom.h
+++ b/stc/crandom.h
@@ -94,15 +94,16 @@ STC_INLINE double crandom_f64(crandom_eng64_t* rng) {
 STC_INLINE crandom_distrib_i64_t crandom_uniform_i64_init(int64_t low, int64_t high) {

     crandom_distrib_i64_t dist = {low, high - low + 1}; return dist;

 }

-STC_INLINE int64_t crandom_uniform_i64(crandom_eng64_t* rng, crandom_distrib_i64_t dist) {

-#if defined(__SIZEOF_INT128__)

-    return dist.offset + (int64_t) (((__uint128_t) crandom_i64(rng) * dist.range) >> 64);

 

-#elif defined(_MSC_VER) && defined(_WIN64)

-    int64_t hi; _umul128(crandom_i64(rng), dist.range, &hi); return dist.offset + hi;

-#else

-    return dist.offset + crandom_i64(rng) % dist.range; // slower

-#endif

+STC_INLINE int64_t crandom_uniform_i64(crandom_eng64_t* rng, crandom_distrib_i64_t dist) {

+    #if defined(__SIZEOF_INT128__)

+        return dist.offset + (int64_t) (((__uint128_t) crandom_i64(rng) * dist.range) >> 64);

+    #elif defined(_MSC_VER) && defined(_WIN64)

+        uint64_t _umul128(uint64_t x, uint64_t y, uint64_t *hi);

+        uint64_t hi; _umul128(crandom_i64(rng), dist.range, &hi); return dist.offset + hi;

+    #else

+        return dist.offset + crandom_i64(rng) % dist.range; // slower

+    #endif

 }

 

 STC_INLINE crandom_distrib_f64_t crandom_uniform_f64_init(double low, double high) {