gcc/testsuite/c-c++-common/analyzer/out-of-bounds-const-fn.c

   1 /* Reduced from analyzer ICE seen with git-2.39.0's pack-bitmap.c
   2    when bounds-checking the result of __builtin_ctzll.  */
   3
   4 #include <stdint.h>
   5 #include <stddef.h>
   6
   7 typedef uint64_t eword_t;
   8 struct ewah_bitmap;
   9 struct ewah_iterator
  10 {
  11   /* [...] */
  12 };
  13 struct bitmap;
  14
  15 void ewah_iterator_init(struct ewah_iterator *it, struct ewah_bitmap *parent);
  16 int ewah_iterator_next(eword_t *next, struct ewah_iterator *it);
  17 void bitmap_set(struct bitmap *self, size_t pos);
  18
  19 int rebuild_bitmap(const uint32_t *reposition,
  20      struct ewah_bitmap *source,
  21      struct bitmap *dest)
  22 {
  23  uint32_t pos = 0;
  24  struct ewah_iterator it;
  25  eword_t word;
  26
  27  ewah_iterator_init(&it, source);
  28
  29  while (ewah_iterator_next(&word, &it)) {
  30   uint32_t offset, bit_pos;
  31
  32   for (offset = 0; offset < (sizeof(eword_t) * 8); ++offset) {
  33    if ((word >> offset) == 0)
  34     break;
  35
  36    offset += __builtin_ctzll(word >> offset);
  37
  38    bit_pos = reposition[pos + offset];
  39    if (bit_pos > 0)
  40     bitmap_set(dest, bit_pos - 1);
  41    else
  42     return -1;
  43   }
  44
  45   pos += (sizeof(eword_t) * 8);
  46  }
  47  return 0;
  48 }