flat bitmap: Add a bitwise and/or/not.

We're about to need them.
This commit is contained in:
David Goldblatt
2020-12-02 19:06:32 -08:00
committed by David Goldblatt
parent 2ae966222f
commit 9b75808be1
2 changed files with 161 additions and 1 deletions

View File

@@ -340,4 +340,34 @@ fb_urange_longest(fb_group_t *fb, size_t nbits) {
return fb_range_longest_impl(fb, nbits, /* val */ false);
}
/*
* Initializes each bit of dst with the bitwise-AND of the corresponding bits of
* src1 and src2. All bitmaps must be the same size.
*/
static inline void
fb_bit_and(fb_group_t *dst, fb_group_t *src1, fb_group_t *src2, size_t nbits) {
size_t ngroups = FB_NGROUPS(nbits);
for (size_t i = 0; i < ngroups; i++) {
dst[i] = src1[i] & src2[i];
}
}
/* Like fb_bit_and, but with bitwise-OR. */
static inline void
fb_bit_or(fb_group_t *dst, fb_group_t *src1, fb_group_t *src2, size_t nbits) {
size_t ngroups = FB_NGROUPS(nbits);
for (size_t i = 0; i < ngroups; i++) {
dst[i] = src1[i] | src2[i];
}
}
/* Initializes dst bit i to the negation of source bit i. */
static inline void
fb_bit_not(fb_group_t *dst, fb_group_t *src, size_t nbits) {
size_t ngroups = FB_NGROUPS(nbits);
for (size_t i = 0; i < ngroups; i++) {
dst[i] = ~src[i];
}
}
#endif /* JEMALLOC_INTERNAL_FB_H */