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-rw-r--r--deps/jemalloc/src/bitmap.c121
1 files changed, 121 insertions, 0 deletions
diff --git a/deps/jemalloc/src/bitmap.c b/deps/jemalloc/src/bitmap.c
new file mode 100644
index 0000000..468b317
--- /dev/null
+++ b/deps/jemalloc/src/bitmap.c
@@ -0,0 +1,121 @@
+#define JEMALLOC_BITMAP_C_
+#include "jemalloc/internal/jemalloc_preamble.h"
+#include "jemalloc/internal/jemalloc_internal_includes.h"
+
+#include "jemalloc/internal/assert.h"
+
+/******************************************************************************/
+
+#ifdef BITMAP_USE_TREE
+
+void
+bitmap_info_init(bitmap_info_t *binfo, size_t nbits) {
+ unsigned i;
+ size_t group_count;
+
+ assert(nbits > 0);
+ assert(nbits <= (ZU(1) << LG_BITMAP_MAXBITS));
+
+ /*
+ * Compute the number of groups necessary to store nbits bits, and
+ * progressively work upward through the levels until reaching a level
+ * that requires only one group.
+ */
+ binfo->levels[0].group_offset = 0;
+ group_count = BITMAP_BITS2GROUPS(nbits);
+ for (i = 1; group_count > 1; i++) {
+ assert(i < BITMAP_MAX_LEVELS);
+ binfo->levels[i].group_offset = binfo->levels[i-1].group_offset
+ + group_count;
+ group_count = BITMAP_BITS2GROUPS(group_count);
+ }
+ binfo->levels[i].group_offset = binfo->levels[i-1].group_offset
+ + group_count;
+ assert(binfo->levels[i].group_offset <= BITMAP_GROUPS_MAX);
+ binfo->nlevels = i;
+ binfo->nbits = nbits;
+}
+
+static size_t
+bitmap_info_ngroups(const bitmap_info_t *binfo) {
+ return binfo->levels[binfo->nlevels].group_offset;
+}
+
+void
+bitmap_init(bitmap_t *bitmap, const bitmap_info_t *binfo, bool fill) {
+ size_t extra;
+ unsigned i;
+
+ /*
+ * Bits are actually inverted with regard to the external bitmap
+ * interface.
+ */
+
+ if (fill) {
+ /* The "filled" bitmap starts out with all 0 bits. */
+ memset(bitmap, 0, bitmap_size(binfo));
+ return;
+ }
+
+ /*
+ * The "empty" bitmap starts out with all 1 bits, except for trailing
+ * unused bits (if any). Note that each group uses bit 0 to correspond
+ * to the first logical bit in the group, so extra bits are the most
+ * significant bits of the last group.
+ */
+ memset(bitmap, 0xffU, bitmap_size(binfo));
+ extra = (BITMAP_GROUP_NBITS - (binfo->nbits & BITMAP_GROUP_NBITS_MASK))
+ & BITMAP_GROUP_NBITS_MASK;
+ if (extra != 0) {
+ bitmap[binfo->levels[1].group_offset - 1] >>= extra;
+ }
+ for (i = 1; i < binfo->nlevels; i++) {
+ size_t group_count = binfo->levels[i].group_offset -
+ binfo->levels[i-1].group_offset;
+ extra = (BITMAP_GROUP_NBITS - (group_count &
+ BITMAP_GROUP_NBITS_MASK)) & BITMAP_GROUP_NBITS_MASK;
+ if (extra != 0) {
+ bitmap[binfo->levels[i+1].group_offset - 1] >>= extra;
+ }
+ }
+}
+
+#else /* BITMAP_USE_TREE */
+
+void
+bitmap_info_init(bitmap_info_t *binfo, size_t nbits) {
+ assert(nbits > 0);
+ assert(nbits <= (ZU(1) << LG_BITMAP_MAXBITS));
+
+ binfo->ngroups = BITMAP_BITS2GROUPS(nbits);
+ binfo->nbits = nbits;
+}
+
+static size_t
+bitmap_info_ngroups(const bitmap_info_t *binfo) {
+ return binfo->ngroups;
+}
+
+void
+bitmap_init(bitmap_t *bitmap, const bitmap_info_t *binfo, bool fill) {
+ size_t extra;
+
+ if (fill) {
+ memset(bitmap, 0, bitmap_size(binfo));
+ return;
+ }
+
+ memset(bitmap, 0xffU, bitmap_size(binfo));
+ extra = (BITMAP_GROUP_NBITS - (binfo->nbits & BITMAP_GROUP_NBITS_MASK))
+ & BITMAP_GROUP_NBITS_MASK;
+ if (extra != 0) {
+ bitmap[binfo->ngroups - 1] >>= extra;
+ }
+}
+
+#endif /* BITMAP_USE_TREE */
+
+size_t
+bitmap_size(const bitmap_info_t *binfo) {
+ return (bitmap_info_ngroups(binfo) << LG_SIZEOF_BITMAP);
+}