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-rw-r--r--deps/jemalloc/src/bitmap.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/deps/jemalloc/src/bitmap.c b/deps/jemalloc/src/bitmap.c
new file mode 100644
index 000000000..b47e26290
--- /dev/null
+++ b/deps/jemalloc/src/bitmap.c
@@ -0,0 +1,90 @@
+#define JEMALLOC_BITMAP_C_
+#include "jemalloc/internal/jemalloc_internal.h"
+
+/******************************************************************************/
+/* Function prototypes for non-inline static functions. */
+
+static size_t bits2groups(size_t nbits);
+
+/******************************************************************************/
+
+static size_t
+bits2groups(size_t nbits)
+{
+
+ return ((nbits >> LG_BITMAP_GROUP_NBITS) +
+ !!(nbits & BITMAP_GROUP_NBITS_MASK));
+}
+
+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 = 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 = bits2groups(group_count);
+ }
+ binfo->levels[i].group_offset = binfo->levels[i-1].group_offset
+ + group_count;
+ binfo->nlevels = i;
+ binfo->nbits = nbits;
+}
+
+size_t
+bitmap_info_ngroups(const bitmap_info_t *binfo)
+{
+
+ return (binfo->levels[binfo->nlevels].group_offset << LG_SIZEOF_BITMAP);
+}
+
+size_t
+bitmap_size(size_t nbits)
+{
+ bitmap_info_t binfo;
+
+ bitmap_info_init(&binfo, nbits);
+ return (bitmap_info_ngroups(&binfo));
+}
+
+void
+bitmap_init(bitmap_t *bitmap, const bitmap_info_t *binfo)
+{
+ size_t extra;
+ unsigned i;
+
+ /*
+ * Bits are actually inverted with regard to the external bitmap
+ * interface, so the 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, binfo->levels[binfo->nlevels].group_offset <<
+ LG_SIZEOF_BITMAP);
+ 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;
+ }
+}