Change /2 to >>1. Surprisingly this improves the speed...

diff --git a/kbtree.h b/kbtree.h
index 0eab778e120ca00028d838ae640a95eb360d9f7a..5ed5330b962918765bb846da682049dab185f1fd 100644 (file)
--- a/kbtree.h
+++ b/kbtree.h
@@ -52,14 +52,14 @@ typedef struct {
        {                                                                                                                                       \
                kbtree_##name##_t *b;                                                                                   \
                b = (kbtree_##name##_t*)calloc(1, sizeof(kbtree_##name##_t));   \
-               b->t = ((size - 4 - sizeof(void*)) / (sizeof(void*) + sizeof(key_t)) + 1) / 2; \
+               b->t = ((size - 4 - sizeof(void*)) / (sizeof(void*) + sizeof(key_t)) + 1) >> 1; \
                if (b->t < 2) {                                                                                                 \
                        free(b); return 0;                                                                                      \
                }                                                                                                                               \
                b->n = 2 * b->t - 1;                                                                                    \
                b->off_ptr = 4 + b->n * sizeof(key_t);                                                  \
-               b->ilen = (4 + sizeof(void*) + b->n * (sizeof(void*) + sizeof(key_t)) + 3) / 4 * 4; \
-               b->elen = (b->off_ptr + 3) / 4 * 4;                                                             \
+               b->ilen = (4 + sizeof(void*) + b->n * (sizeof(void*) + sizeof(key_t)) + 3) >> 2 << 2; \
+               b->elen = (b->off_ptr + 3) >> 2 << 2;                                                   \
                b->root = (kbnode_t*)calloc(1, b->ilen);                                                \
                ++b->n_nodes;                                                                                                   \
                return b;                                                                                                               \
@@ -99,7 +99,7 @@ typedef struct {
 #define __KB_GET_AUX0(name, key_t, __cmp)                                                              \
        static inline int __kb_get_aux_##name(const kbnode_t * __restrict x, const key_t * __restrict k, int *r) \
        {                                                                                                                                       \
-               int tr, *rr, begin, end, n = x->n / 2;                                                  \
+               int tr, *rr, begin, end, n = x->n >> 1;                                                 \
                if (x->n == 0) return -1;                                                                               \
                if (__cmp(*k, __KB_KEY(key_t, x)[n]) < 0) {                                             \
                        begin = 0; end = n;                                                                                     \
@@ -117,7 +117,7 @@ typedef struct {
                if (x->n == 0) return -1;                                                                               \
                rr = r? r : &tr;                                                                                                \
                while (begin < end) {                                                                                   \
-                       int mid = (begin + end) / 2;                                                            \
+                       int mid = (begin + end) >> 1;                                                           \
                        if (__cmp(__KB_KEY(key_t, x)[mid], *k) < 0) begin = mid + 1; \
                        else end = mid;                                                                                         \
                }                                                                                                                               \