diff options
Diffstat (limited to 'libcpp/line-map.c')
| -rw-r--r-- | libcpp/line-map.c | 39 |
1 files changed, 33 insertions, 6 deletions
diff --git a/libcpp/line-map.c b/libcpp/line-map.c index 9086b3e..87b8bfe 100644 --- a/libcpp/line-map.c +++ b/libcpp/line-map.c @@ -92,16 +92,43 @@ new_linemap (struct line_maps *set, if (LINEMAPS_USED (set, macro_map_p) == LINEMAPS_ALLOCATED (set, macro_map_p)) { /* We ran out of allocated line maps. Let's allocate more. */ + unsigned alloc_size; line_map_realloc reallocator = set->reallocator ? set->reallocator : xrealloc; + line_map_round_alloc_size_func round_alloc_size = + set->round_alloc_size; + + /* We are going to execute some dance to try to reduce the + overhead of the memory allocator, in case we are using the + ggc-page.c one. + + The actual size of memory we are going to get back from the + allocator is the smallest power of 2 that is greater than the + size we requested. So let's consider that size then. */ + + alloc_size = + (2 * LINEMAPS_ALLOCATED (set, macro_map_p) + 256) + * sizeof (struct line_map); + + /* Get the actual size of memory that is going to be allocated + by the allocator. */ + alloc_size = round_alloc_size (alloc_size); + + /* Now alloc_size contains the exact memory size we would get if + we have asked for the initial alloc_size amount of memory. + Let's get back to the number of macro map that amounts + to. */ LINEMAPS_ALLOCATED (set, macro_map_p) = - 2 * LINEMAPS_ALLOCATED (set, macro_map_p) + 256; - LINEMAPS_MAPS (set, macro_map_p) - = (struct line_map *) (*reallocator) (LINEMAPS_MAPS (set, macro_map_p), - LINEMAPS_ALLOCATED (set, - macro_map_p) - * sizeof (struct line_map)); + alloc_size / (sizeof (struct line_map)); + + /* And now let's really do the re-allocation. */ + LINEMAPS_MAPS (set, macro_map_p) = + (struct line_map *) (*reallocator) + (LINEMAPS_MAPS (set, macro_map_p), + (LINEMAPS_ALLOCATED (set, macro_map_p) + * sizeof (struct line_map))); + result = &LINEMAPS_MAPS (set, macro_map_p)[LINEMAPS_USED (set, macro_map_p)]; memset (result, 0, |