From patchwork Tue Mar 5 12:00:19 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Bosscher X-Patchwork-Id: 224991 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) by ozlabs.org (Postfix) with SMTP id 536D92C0089 for ; Tue, 5 Mar 2013 23:01:42 +1100 (EST) Comment: DKIM? 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Such patterns result in linked-list walks, and can trigger behavior quadratic in the number of linked-list member elements in the set. The attached patch is a first stab at an idea I've had for a while: Implement a "change of view" for bitmaps, such that a bitmap can be either a linked list, or a binary tree. I've implemented this idea with top-down splay trees because splay tree nodes do not need meta-data on (unlike e.g. color for RB-trees, rank for AVL trees, etc.) and top-down splay tree operations are very simple to implement (less than 200 lines of code). As far as I'm aware, this is the first attempt at allowing different views on bitmaps. The idea came from Andrew Macleod's tree-ssa-live implementation. The idea is to convert the bitmap to a tree view if the set represented by the bitmap is mostly used for membership testing, and not for iterations over the items (as e.g. for bitmap dataflow). A typical example of this is e.g. invalid_mode_changes, which just explodes for the test case of PR55135 at -O0. I haven't tested this patch at all, except making sure that it compiles. Just posting this for discussion, and for feedback on the idea. I know there have been many others before me who've tried different data structures for bitmaps, perhaps someone has already tried this before. Ciao! Steven Index: bitmap.h =================================================================== --- bitmap.h (revision 196410) +++ bitmap.h (working copy) @@ -20,16 +20,21 @@ along with GCC; see the file COPYING3. #ifndef GCC_BITMAP_H #define GCC_BITMAP_H -/* Implementation of sparse integer sets as a linked list. +/* Implementation of sparse integer sets as a linked list or trees. This sparse set representation is suitable for sparse sets with an - unknown (a priori) universe. The set is represented as a double-linked - list of container nodes (struct bitmap_element_def). Each node consists - of an index for the first member that could be held in the container, - a small array of integers that represent the members in the container, - and pointers to the next and previous element in the linked list. The - elements in the list are sorted in ascending order, i.e. the head of + unknown (a priori) universe. + + Sets are represented as double-linked lists of container nodes of + type "struct bitmap_element_def" or as a binary trees of the same + container nodes. Each container node consists of an index for the + first member that could be held in the container, a small array of + integers that represent the members in the container, and pointers + to the next and previous element in the linked list, or left and + right children in the tree. In linked-list form, the container + nodes in the list are sorted in ascending order, i.e. the head of the list holds the element with the smallest member of the set. + In tree form, nodes to the left have a smaller container index. For a given member I in the set: - the element for I will have index is I / (bits per element) @@ -42,17 +47,67 @@ along with GCC; see the file COPYING3. high storage overhead *per element*, but a small overall overhead if the set is very sparse. - The downside is that many operations are relatively slow because the - linked list has to be traversed to test membership (i.e. member_p/ - add_member/remove_member). To improve the performance of this set - representation, the last accessed element and its index are cached. - For membership tests on members close to recently accessed members, - the cached last element improves membership test to a constant-time - operation. + The storage requirements for linked-list sparse sets are O(E), with E->N + in the worst case (a sparse set with large distances between the values + of the set members). + + This representation also works well for data flow problems where the size + of the set may grow dynamically, but care must be taken that the member_p, + add_member, and remove_member operations occur with a suitable access + pattern. + + The linked-list set representation works well for problems involving very + sparse sets. The canonical example in GCC is, of course, the "set of + sets" for some CFG-based data flow problems (liveness analysis, dominance + frontiers, etc.). + + For random-access sparse sets of unknown universe, the binary tree + representation is likely to be a more suitable choice. Theoretical + access times for the binary tree representation are better than those + for the linked-list, but in practice this is only true for truely + random access. + + Often the most suitable representation during construction of the set + is not the best choice for the usage of the set. For such cases, the + "view" of the set can be changed from one representation to the other. + This is an O(E) operation. + + TODO: Document bitmap view changes! -- STEVEN + + Traversing linked lists or trees can be cache-unfriendly. Performance + can be improved by keeping container nodes in the set grouped together + in memory, using a dedicated obstack for a set (or group of related + sets). Elements allocated on obstacks are released to a free-list and + taken off the free list. If multiple sets are allocated on the same + obstack, elements freed from one set may be re-used for one of the other + sets. This usually helps avoid cache misses. + + A single free-list is used for all sets allocated in GGC space. This is + bad for persistent sets, so persistent sets should be allocated on an + obstack whenever possible. + + For random-access sets with a known, relatively small universe size, the + SparseSet or simple bitmap representations may be more efficient than a + linked-list set. + + + LINKED LIST FORM + ================ + + In linked-list form, in-order iterations of the set can be executed + efficiently. The downside is that many random-access operations are + relatively slow, because the linked list has to be traversed to test + membership (i.e. member_p/ add_member/remove_member). + + To improve the performance of this set representation, the last + accessed element and its index are cached. For membership tests on + members close to recently accessed members, the cached last element + improves membership test to a constant-time operation. The following operations can always be performed in O(1) time: * clear : bitmap_clear + * smallest_member : bitmap_first_set_bit * choose_one : (not implemented, but could be implemented in constant time) @@ -61,15 +116,16 @@ along with GCC; see the file COPYING3. suitable access patterns: * member_p : bitmap_bit_p - * add_member : bitmap_set_bit - * remove_member : bitmap_clear_bit + * add_member : bitmap_set_bit / bitmap_set_range + * remove_member : bitmap_clear_bit / bitmap_clear_range The following operations can be performed in O(E) time: * cardinality : bitmap_count_bits - * set_size : bitmap_last_set_bit (but this could + * largest_member : bitmap_last_set_bit (but this could in constant time with a pointer to the last element in the chain) + * set_size : bitmap_last_set_bit Additionally, the linked-list sparse set representation supports enumeration of the members in O(E) time: @@ -93,39 +149,53 @@ along with GCC; see the file COPYING3. * A | (B & ~C) : bitmap_ior_and_compl / bitmap_ior_and_compl_into - The storage requirements for linked-list sparse sets are O(E), with E->N - in the worst case (a sparse set with large distances between the values - of the set members). - The linked-list set representation works well for problems involving very - sparse sets. The canonical example in GCC is, of course, the "set of - sets" for some CFG-based data flow problems (liveness analysis, dominance - frontiers, etc.). - - This representation also works well for data flow problems where the size - of the set may grow dynamically, but care must be taken that the member_p, - add_member, and remove_member operations occur with a suitable access - pattern. + BINARY TREE FORM + ================ + An alternate "view" of a bitmap is its binary tree representation. + For this representation, splay trees are used because they can be + implemented using the same data structures as the linked list, with + no overhead for meta-data (like color, or rank) on the tree nodes. + + In binary tree form, random-access to the set is much more efficient + than for the linked-list representation. Downsides are the high cost + of clearing the set, and the relatively large number of operations + necessary to balance the tree. Also, iterating the set members is + not supported. - For random-access sets with a known, relatively small universe size, the - SparseSet or simple bitmap representations may be more efficient than a - linked-list set. For random-access sets of unknown universe, a hash table - or a balanced binary tree representation is likely to be a more suitable - choice. + As for the linked-list representation, the last accessed element and + its index are cached, so that membership tests on the latest accessed + members is a constant-time operation. Other lookups take O(logE) + time amortized (but O(E) time worst-case). - Traversing linked lists is usually cache-unfriendly, even with the last - accessed element cached. - - Cache performance can be improved by keeping the elements in the set - grouped together in memory, using a dedicated obstack for a set (or group - of related sets). Elements allocated on obstacks are released to a - free-list and taken off the free list. If multiple sets are allocated on - the same obstack, elements freed from one set may be re-used for one of - the other sets. This usually helps avoid cache misses. + The following operations can always be performed in O(1) time: - A single free-list is used for all sets allocated in GGC space. This is - bad for persistent sets, so persistent sets should be allocated on an - obstack whenever possible. */ + * choose_one : (not implemented, but could be + implemented in constant time) + + The following operations can be performed in O(logE) time amortized + but O(E) time worst-case, but in O(1) time if the same element is + accessed. + + * member_p : bitmap_bit_p + * add_member : bitmap_set_bit + * remove_member : bitmap_clear_bit + + The following operations can be performed in O(logE) time amortized + but O(E) time worst-case: + + * smallest_member : bitmap_first_set_bit + * largest_member : bitmap_last_set_bit + * set_size : bitmap_last_set_bit + + The following operations can be performed in O(E) time: + + * clear : bitmap_clear + + The binary tree sparse set representation does *not* support any form + of enumeration, and does also *not* support logical operations on sets. + The binary tree representation is only supposed to be used for sets + on which many random-access membership tests will happen. */ #include "hashtab.h" #include "statistics.h" @@ -168,24 +238,46 @@ typedef struct GTY (()) bitmap_obstack { linear in the number of elements to be freed. */ typedef struct GTY((chain_next ("%h.next"), chain_prev ("%h.prev"))) bitmap_element_def { - struct bitmap_element_def *next; /* Next element. */ - struct bitmap_element_def *prev; /* Previous element. */ - unsigned int indx; /* regno/BITMAP_ELEMENT_ALL_BITS. */ - BITMAP_WORD bits[BITMAP_ELEMENT_WORDS]; /* Bits that are set. */ + /* In list form, the next element in the linked list; + in tree form, the left child node in the tree. */ + struct bitmap_element_def *next; + + /* In list form, the previous element in the linked list; + in tree form, the right child node in the tree. */ + struct bitmap_element_def *prev; + + /* regno/BITMAP_ELEMENT_ALL_BITS. */ + unsigned int indx; + + /* Bits that are set, counting from INDX, inclusive. */ + BITMAP_WORD bits[BITMAP_ELEMENT_WORDS]; } bitmap_element; /* Head of bitmap linked list. The 'current' member points to something already pointed to by the chain started by first, so GTY((skip)) it. */ typedef struct GTY(()) bitmap_head_def { - unsigned int indx; /* Index of last element looked at. */ - unsigned int descriptor_id; /* Unique identifier for the allocation - site of this bitmap, for detailed - statistics gathering. */ - bitmap_element *first; /* First element in linked list. */ - bitmap_element * GTY((skip(""))) current; /* Last element looked at. */ - bitmap_obstack *obstack; /* Obstack to allocate elements from. - If NULL, then use GGC allocation. */ + /* Index of last element looked at. */ + unsigned int indx; + + /* Unique identifier for the allocation site of this bitmap, + for detailed statistics gathering. */ + unsigned int descriptor_id : 31; + + /* 0 if the bitmap is in list form; 1 if the bitmap is in tree form. + Bitmap iterators only work on bitmaps in list form. */ + unsigned int tree_form : 1; + + /* In list form, the first element in the linked list; + in tree form, The root of the tree. */ + bitmap_element *first; + + /* Last element looked at. */ + bitmap_element * GTY((skip(""))) current; + + /* Obstack to allocate elements from. + If NULL, then use GGC allocation. */ + bitmap_obstack *obstack; } bitmap_head; /* Global data */ @@ -252,15 +344,15 @@ extern bool bitmap_clear_bit (bitmap, in /* Set a single bit in a bitmap. Return true if the bit changed. */ extern bool bitmap_set_bit (bitmap, int); -/* Return true if a register is set in a register set. */ +/* Return true if a bit is set in a bitmap. */ extern int bitmap_bit_p (bitmap, int); -/* Debug functions to print a bitmap linked list. */ -extern void debug_bitmap (const_bitmap); -extern void debug_bitmap_file (FILE *, const_bitmap); +/* Debug functions to print a bitmap. */ +extern void debug_bitmap (bitmap); +extern void debug_bitmap_file (FILE *, bitmap); /* Print a bitmap. */ -extern void bitmap_print (FILE *, const_bitmap, const char *, const char *); +extern void bitmap_print (FILE *, bitmap, const char *, const char *); /* Initialize and release a bitmap obstack. */ extern void bitmap_obstack_initialize (bitmap_obstack *); @@ -275,6 +367,7 @@ static inline void bitmap_initialize_stat (bitmap head, bitmap_obstack *obstack MEM_STAT_DECL) { head->first = head->current = NULL; + head->indx = head->tree_form = 0; head->obstack = obstack; if (GATHER_STATISTICS) bitmap_register (head PASS_MEM_STAT); @@ -289,7 +382,7 @@ extern bitmap bitmap_gc_alloc_stat (ALON extern void bitmap_obstack_free (bitmap); /* A few compatibility/functions macros for compatibility with sbitmaps */ -inline void dump_bitmap (FILE *file, const_bitmap map) +inline void dump_bitmap (FILE *file, bitmap map) { bitmap_print (file, map, "", "\n"); } @@ -310,7 +403,9 @@ extern hashval_t bitmap_hash(const_bitma #define BITMAP_FREE(BITMAP) \ ((void) (bitmap_obstack_free ((bitmap) BITMAP), (BITMAP) = (bitmap) NULL)) -/* Iterator for bitmaps. */ +/* Iterator for bitmaps. + TODO: These iterators only work on bitmaps in list form. + Having them working for tree bitmaps also would be nice. */ typedef struct { @@ -339,6 +434,8 @@ bmp_iter_set_init (bitmap_iterator *bi, bi->elt1 = map->first; bi->elt2 = NULL; + gcc_checking_assert (!map->tree_form); + /* Advance elt1 until it is not before the block containing start_bit. */ while (1) { @@ -381,6 +478,8 @@ bmp_iter_and_init (bitmap_iterator *bi, bi->elt1 = map1->first; bi->elt2 = map2->first; + gcc_checking_assert (!map1->tree_form && !map2->tree_form); + /* Advance elt1 until it is not before the block containing start_bit. */ while (1) @@ -439,8 +538,7 @@ bmp_iter_and_init (bitmap_iterator *bi, *bit_no = start_bit; } -/* Initialize an iterator to iterate over the bits in MAP1 & ~MAP2. - */ +/* Initialize an iterator to iterate over the bits in MAP1 & ~MAP2. */ static inline void bmp_iter_and_compl_init (bitmap_iterator *bi, @@ -450,6 +548,8 @@ bmp_iter_and_compl_init (bitmap_iterator bi->elt1 = map1->first; bi->elt2 = map2->first; + gcc_checking_assert (!map1->tree_form && !map2->tree_form); + /* Advance elt1 until it is not before the block containing start_bit. */ while (1) { Index: bitmap.c =================================================================== --- bitmap.c (revision 196410) +++ bitmap.c (working copy) @@ -44,6 +44,8 @@ struct bitmap_descriptor_d typedef struct bitmap_descriptor_d *bitmap_descriptor; typedef const struct bitmap_descriptor_d *const_bitmap_descriptor; +static bitmap_element *bitmap_tree_listify_from (bitmap, bitmap_element *); + /* Next available unique id number for bitmap desciptors. */ static int next_bitmap_desc_id = 0; @@ -95,6 +97,11 @@ get_bitmap_descriptor (const char *file, if (*slot) return *slot; + /* The descriptor ID can be at most 31 bits long, because the most + significant of the (half)word is used to identify the mode of + the bitmap, i.e. whether its current form is list or tree. */ + gcc_assert (next_bitmap_desc_id < (1 << 30) - 1); // TODO: make descriptor ID unsigned + *slot = XCNEW (struct bitmap_descriptor_d); bitmap_descriptors.safe_push (*slot); (*slot)->id = next_bitmap_desc_id++; @@ -133,22 +140,18 @@ static int bitmap_default_obstack_depth; static GTY((deletable)) bitmap_element *bitmap_ggc_free; /* Freelist of GC'd elements. */ -static void bitmap_elem_to_freelist (bitmap, bitmap_element *); -static void bitmap_element_free (bitmap, bitmap_element *); -static bitmap_element *bitmap_element_allocate (bitmap); -static int bitmap_element_zerop (const bitmap_element *); -static void bitmap_element_link (bitmap, bitmap_element *); -static bitmap_element *bitmap_elt_insert_after (bitmap, bitmap_element *, unsigned int); -static void bitmap_elt_clear_from (bitmap, bitmap_element *); -static bitmap_element *bitmap_find_bit (bitmap, unsigned int); +/* Bitmap memory management. */ -/* Add ELEM to the appropriate freelist. */ +/* Add ELT to the appropriate freelist. */ static inline void bitmap_elem_to_freelist (bitmap head, bitmap_element *elt) { bitmap_obstack *bit_obstack = head->obstack; + if (GATHER_STATISTICS) + register_overhead (head, -((int)sizeof (bitmap_element))); + elt->next = NULL; if (bit_obstack) { @@ -162,41 +165,6 @@ bitmap_elem_to_freelist (bitmap head, bi } } -/* Free a bitmap element. Since these are allocated off the - bitmap_obstack, "free" actually means "put onto the freelist". */ - -static inline void -bitmap_element_free (bitmap head, bitmap_element *elt) -{ - bitmap_element *next = elt->next; - bitmap_element *prev = elt->prev; - - if (prev) - prev->next = next; - - if (next) - next->prev = prev; - - if (head->first == elt) - head->first = next; - - /* Since the first thing we try is to insert before current, - make current the next entry in preference to the previous. */ - if (head->current == elt) - { - head->current = next != 0 ? next : prev; - if (head->current) - head->indx = head->current->indx; - else - head->indx = 0; - } - - if (GATHER_STATISTICS) - register_overhead (head, -((int)sizeof (bitmap_element))); - - bitmap_elem_to_freelist (head, elt); -} - /* Allocate a bitmap element. The bits are cleared, but nothing else is. */ static inline bitmap_element * @@ -249,7 +217,8 @@ bitmap_element_allocate (bitmap head) return element; } -/* Remove ELT and all following elements from bitmap HEAD. */ +/* Remove ELT and all following elements from bitmap HEAD. + Put the released elements in the freelist for HEAD. */ void bitmap_elt_clear_from (bitmap head, bitmap_element *elt) @@ -257,7 +226,11 @@ bitmap_elt_clear_from (bitmap head, bitm bitmap_element *prev; bitmap_obstack *bit_obstack = head->obstack; - if (!elt) return; + if (!elt) + return; + + if (head->tree_form) + elt = bitmap_tree_listify_from (head, elt); if (GATHER_STATISTICS) { @@ -284,7 +257,7 @@ bitmap_elt_clear_from (bitmap head, bitm head->indx = 0; } - /* Put the entire list onto the free list in one operation. */ + /* Put the entire list onto the freelist in one operation. */ if (bit_obstack) { elt->prev = bit_obstack->elements; @@ -296,12 +269,453 @@ bitmap_elt_clear_from (bitmap head, bitm bitmap_ggc_free = elt; } } + +/* Linked-list view of bitmaps. + + In this representation, the bitmap elements form a double-linked list + with elements sorted by increasing index. */ + +/* Link the bitmap element into the current bitmap linked list. */ + +static inline void +bitmap_list_link_element (bitmap head, bitmap_element *element) +{ + unsigned int indx = element->indx; + bitmap_element *ptr; + + gcc_checking_assert (!head->tree_form); + + /* If this is the first and only element, set it in. */ + if (head->first == 0) + { + element->next = element->prev = 0; + head->first = element; + } + + /* If this index is less than that of the current element, it goes someplace + before the current element. */ + else if (indx < head->indx) + { + for (ptr = head->current; + ptr->prev != 0 && ptr->prev->indx > indx; + ptr = ptr->prev) + ; + + if (ptr->prev) + ptr->prev->next = element; + else + head->first = element; + + element->prev = ptr->prev; + element->next = ptr; + ptr->prev = element; + } + + /* Otherwise, it must go someplace after the current element. */ + else + { + for (ptr = head->current; + ptr->next != 0 && ptr->next->indx < indx; + ptr = ptr->next) + ; + + if (ptr->next) + ptr->next->prev = element; + + element->next = ptr->next; + element->prev = ptr; + ptr->next = element; + } + + /* Set up so this is the first element searched. */ + head->current = element; + head->indx = indx; +} + +/* Unlink the bitmap element from the current bitmap linked list, + and return it to the freelist. */ + +static inline void +bitmap_list_unlink_element (bitmap head, bitmap_element *element) +{ + bitmap_element *next = element->next; + bitmap_element *prev = element->prev; + + gcc_checking_assert (!head->tree_form); + + if (prev) + prev->next = next; + + if (next) + next->prev = prev; + + if (head->first == element) + head->first = next; + + /* Since the first thing we try is to insert before current, + make current the next entry in preference to the previous. */ + if (head->current == element) + { + head->current = next != 0 ? next : prev; + if (head->current) + head->indx = head->current->indx; + else + head->indx = 0; + } + + bitmap_elem_to_freelist (head, element); +} + +/* Insert a new uninitialized element into bitmap HEAD after element + ELT. If ELT is NULL, insert the element at the start. Return the + new element. */ + +static bitmap_element * +bitmap_list_insert_element_after (bitmap head, + bitmap_element *elt, unsigned int indx) +{ + bitmap_element *node = bitmap_element_allocate (head); + node->indx = indx; + + gcc_checking_assert (!head->tree_form); + + if (!elt) + { + if (!head->current) + { + head->current = node; + head->indx = indx; + } + node->next = head->first; + if (node->next) + node->next->prev = node; + head->first = node; + node->prev = NULL; + } + else + { + gcc_checking_assert (head->current); + node->next = elt->next; + if (node->next) + node->next->prev = node; + elt->next = node; + node->prev = elt; + } + return node; +} + +/* Return the element for INDX, or NULL if the element doesn't exist. */ + +static inline bitmap_element * +bitmap_list_find_element (bitmap head, unsigned int indx) +{ + bitmap_element *element; + if (head->indx < indx) + /* INDX is beyond head->indx. Search from head->current + forward. */ + for (element = head->current; + element->next != 0 && element->indx < indx; + element = element->next) + { + if (GATHER_STATISTICS) + bitmap_descriptors[head->descriptor_id]->search_iter++; + } + + else if (head->indx / 2 < indx) + /* INDX is less than head->indx and closer to head->indx than to + 0. Search from head->current backward. */ + for (element = head->current; + element->prev != 0 && element->indx > indx; + element = element->prev) + { + if (GATHER_STATISTICS) + bitmap_descriptors[head->descriptor_id]->search_iter++; + } + + else + /* INDX is less than head->indx and closer to 0 than to + head->indx. Search from head->first forward. */ + for (element = head->first; + element->next != 0 && element->indx < indx; + element = element->next) + if (GATHER_STATISTICS) + { + bitmap_descriptors[head->descriptor_id]->search_iter++; + } + + /* `element' is the nearest to the one we want. If it's not the one we + want, the one we want doesn't exist. */ + head->current = element; + head->indx = element->indx; + if (element != 0 && element->indx != indx) + element = 0; + return element; +} + + +/* Splay-tree view of bitmaps. + + This is an almost one-to-one the implementatin of the simple top-down + splay tree in Sleator and Tarjan's "Self-adjusting Binary Search Trees". + It is probably not the most efficient form of splay trees, but it should + be good enough to experiment with this idea of bitmaps-as-trees. + + For all functions below, the variable or function argument "t" is a node + in the tree, and "e" is a temporary or new node in the tree. The rest + is sufficiently straigh-forward (and very well explained in the paper) + that comment would only clutter things. */ + +static inline void +bitmap_tree_link_left (bitmap_element * &t, bitmap_element * &l) +{ + l->next = t; + l = t; + t = t->next; +} + +static inline void +bitmap_tree_link_right (bitmap_element * &t, bitmap_element * &r) +{ + r->prev = t; + r = t; + t = t->prev; +} + +static inline void +bitmap_tree_rotate_left (bitmap_element * &t) +{ + bitmap_element *e = t->next; + t->next = t->next->prev; + e->prev = t; + t = e; +} + +static inline void +bitmap_tree_rotate_right (bitmap_element * &t) +{ + bitmap_element *e = t->prev; + t->prev = t->prev->next; + e->next = t; + t = e; +} + +static bitmap_element * +bitmap_tree_splay (bitmap head, bitmap_element *t, unsigned int indx) +{ + bitmap_element N, *l, *r; + + if (t == NULL) + return NULL; + + N.prev = N.next = NULL; + l = r = &N; + + while (indx != t->indx) + { + if (GATHER_STATISTICS) + bitmap_descriptors[head->descriptor_id]->search_iter++; + + if (indx < t->indx) + { + if (t->prev != NULL && indx < t->prev->indx) + bitmap_tree_rotate_right (t); + if (t->prev == NULL) + break; + bitmap_tree_link_right (t, r); + } + else if (indx > t->indx) + { + if (t->next != NULL && indx > t->next->indx) + bitmap_tree_rotate_left (t); + if (t->next == NULL) + break; + bitmap_tree_link_left (t, l); + } + } + + l->next = t->prev; + r->prev = t->next; + t->prev = N.next; + t->next = N.prev; + return t; +} -/* Clear a bitmap by freeing the linked list. */ +/* Link bitmap element E into the current bitmap splay tree. */ + +static inline void +bitmap_tree_link_element (bitmap head, bitmap_element *e) +{ + if (head->first == NULL) + e->prev = e->next = NULL; + else + { + bitmap_element *t = bitmap_tree_splay (head, head->first, e->indx); + if (e->indx < t->indx) + { + e->prev = t->prev; + e->next = t; + t->prev = NULL; + } + else if (e->indx > t->indx) + { + e->next = t->next; + e->prev = t; + t->next = NULL; + } + else + gcc_unreachable (); + } + head->first = e; + head->current = e; + head->indx = e->indx; +} + +/* Unlink bitmap element E from the current bitmap splay tree, + and return it to the freelist. */ + +static void +bitmap_tree_unlink_element (bitmap head, bitmap_element *e) +{ + bitmap_element *t = bitmap_tree_splay (head, head->first, e->indx); + + gcc_checking_assert (t == e); + + if (e->prev == NULL) + t = e->next; + else + { + t = bitmap_tree_splay (head, e->prev, e->indx); + t->next = e->next; + } + head->first = t; + head->current = t; + head->indx = (t != NULL) ? t->indx : 0; +} + +/* Return the element for INDX, or NULL if the element doesn't exist. */ + +static inline bitmap_element * +bitmap_tree_find_element (bitmap head, unsigned int indx) +{ + bitmap_element *e= bitmap_tree_splay (head, head->first, indx); + head->first = e; + if (e->indx == indx) + { + head->current = e; + head->indx = e->indx; + } + return e; +} + +/* Converting bitmap views from linked-list to tree and vice versa. */ + +/* Splice element E and all elements with a larger index from + bitmap HEAD, convert the spliced elements to the linked-list + view, and return the head of the list (which should be E again), */ + +static bitmap_element * +bitmap_tree_listify_from (bitmap head, bitmap_element *e) +{ + bitmap_element *t = bitmap_tree_splay (head, head->first, e->indx); + gcc_checking_assert (t == e); + + t = t->prev; + head->first = t; + head->current = t; + head->indx = (t != NULL) ? t->indx : 0; + + /* The tree is now valid again. Now we need to "un-tree" E. + It is imperative that a non-recursive implementation is used + for this, because splay trees have a worst case depth of O(E). + A recursive implementation would result in a stack overflow + for a sufficiently large, unbalanced bitmap tree. */ + vec stack = vNULL; + vec sorted_elements = vNULL; + bitmap_element *n = e; + + while (true) + { + while (n != NULL) + { + stack.safe_push (n); + n = n->prev; + } + + if (stack.is_empty ()) + break; + + n = stack.pop (); + sorted_elements.safe_push (n); + n = n->next; + } + stack.release (); + + gcc_assert (sorted_elements[0] == e); + + bitmap_element *prev = NULL; + unsigned ix; + FOR_EACH_VEC_ELT (sorted_elements, ix, n) + { + if (prev != NULL) + prev->next = n; + n->prev = prev; + n->next = NULL; + } + sorted_elements.release (); + + return e; +} + +/* Convert bitmap HEAD from splay-tree view to linked-list view. */ + +void +bitmap_list_view (bitmap head) +{ + bitmap_element *ptr; + + head->tree_form = 0; + if (! head->first) + return; + + ptr = head->first; + while (ptr->prev) + ptr = ptr->prev; + head->first = bitmap_tree_listify_from (head, ptr); + + head->current = head->first; + head->indx = head->first->indx; +} + +/* Convert bitmap HEAD from linked-list view to splay-tree view. + This is simply a matter of dropping the prev or next pointers + and setting the tree_form flag. The tree will balance itself + if and when it is used. */ + +void +bitmap_tree_view (bitmap head) +{ + bitmap_element *ptr; + + head->tree_form = 1; + if (! head->first) + return; + + ptr = head->first; + while (ptr) + { + ptr->prev = NULL; + ptr = ptr->next; + } + head->current = head->first; + head->indx = head->first->indx; +} + +/* Clear a bitmap by freeing all its elements. */ void bitmap_clear (bitmap head) { +//listify the tree if head is in tree form if (head->first) bitmap_elt_clear_from (head, head->first); } @@ -427,96 +841,6 @@ bitmap_element_zerop (const bitmap_eleme #endif } -/* Link the bitmap element into the current bitmap linked list. */ - -static inline void -bitmap_element_link (bitmap head, bitmap_element *element) -{ - unsigned int indx = element->indx; - bitmap_element *ptr; - - /* If this is the first and only element, set it in. */ - if (head->first == 0) - { - element->next = element->prev = 0; - head->first = element; - } - - /* If this index is less than that of the current element, it goes someplace - before the current element. */ - else if (indx < head->indx) - { - for (ptr = head->current; - ptr->prev != 0 && ptr->prev->indx > indx; - ptr = ptr->prev) - ; - - if (ptr->prev) - ptr->prev->next = element; - else - head->first = element; - - element->prev = ptr->prev; - element->next = ptr; - ptr->prev = element; - } - - /* Otherwise, it must go someplace after the current element. */ - else - { - for (ptr = head->current; - ptr->next != 0 && ptr->next->indx < indx; - ptr = ptr->next) - ; - - if (ptr->next) - ptr->next->prev = element; - - element->next = ptr->next; - element->prev = ptr; - ptr->next = element; - } - - /* Set up so this is the first element searched. */ - head->current = element; - head->indx = indx; -} - -/* Insert a new uninitialized element into bitmap HEAD after element - ELT. If ELT is NULL, insert the element at the start. Return the - new element. */ - -static bitmap_element * -bitmap_elt_insert_after (bitmap head, bitmap_element *elt, unsigned int indx) -{ - bitmap_element *node = bitmap_element_allocate (head); - node->indx = indx; - - if (!elt) - { - if (!head->current) - { - head->current = node; - head->indx = indx; - } - node->next = head->first; - if (node->next) - node->next->prev = node; - head->first = node; - node->prev = NULL; - } - else - { - gcc_checking_assert (head->current); - node->next = elt->next; - if (node->next) - node->next->prev = node; - elt->next = node; - node->prev = elt; - } - return node; -} - /* Copy a bitmap to another bitmap. */ void @@ -525,6 +849,8 @@ bitmap_copy (bitmap to, const_bitmap fro const bitmap_element *from_ptr; bitmap_element *to_ptr = 0; + gcc_checking_assert (!to->tree_form && !from->tree_form); + bitmap_clear (to); /* Copy elements in forward direction one at a time. */ @@ -535,8 +861,9 @@ bitmap_copy (bitmap to, const_bitmap fro to_elt->indx = from_ptr->indx; memcpy (to_elt->bits, from_ptr->bits, sizeof (to_elt->bits)); - /* Here we have a special case of bitmap_element_link, for the case - where we know the links are being entered in sequence. */ + /* Here we have a special case of bitmap_list_link_element, + for the case where we know the links are being entered + in sequence. */ if (to_ptr == 0) { to->first = to->current = to_elt; @@ -572,45 +899,10 @@ bitmap_find_bit (bitmap head, unsigned i if (GATHER_STATISTICS) bitmap_descriptors[head->descriptor_id]->nsearches++; - if (head->indx < indx) - /* INDX is beyond head->indx. Search from head->current - forward. */ - for (element = head->current; - element->next != 0 && element->indx < indx; - element = element->next) - { - if (GATHER_STATISTICS) - bitmap_descriptors[head->descriptor_id]->search_iter++; - } - - else if (head->indx / 2 < indx) - /* INDX is less than head->indx and closer to head->indx than to - 0. Search from head->current backward. */ - for (element = head->current; - element->prev != 0 && element->indx > indx; - element = element->prev) - { - if (GATHER_STATISTICS) - bitmap_descriptors[head->descriptor_id]->search_iter++; - } - + if (!head->tree_form) + element = bitmap_list_find_element (head, indx); else - /* INDX is less than head->indx and closer to 0 than to - head->indx. Search from head->first forward. */ - for (element = head->first; - element->next != 0 && element->indx < indx; - element = element->next) - if (GATHER_STATISTICS) - { - bitmap_descriptors[head->descriptor_id]->search_iter++; - } - - /* `element' is the nearest to the one we want. If it's not the one we - want, the one we want doesn't exist. */ - head->current = element; - head->indx = element->indx; - if (element != 0 && element->indx != indx) - element = 0; + element = bitmap_tree_find_element (head, indx); return element; } @@ -634,7 +926,12 @@ bitmap_clear_bit (bitmap head, int bit) /* If we cleared the entire word, free up the element. */ if (!ptr->bits[word_num] && bitmap_element_zerop (ptr)) - bitmap_element_free (head, ptr); + { + if (!head->tree_form) + bitmap_list_unlink_element (head, ptr); + else + bitmap_tree_unlink_element (head, ptr); + } } return res; @@ -653,21 +950,22 @@ bitmap_set_bit (bitmap head, int bit) unsigned bit_num = bit % BITMAP_WORD_BITS; BITMAP_WORD bit_val = ((BITMAP_WORD) 1) << bit_num; - if (ptr == 0) - { - ptr = bitmap_element_allocate (head); - ptr->indx = bit / BITMAP_ELEMENT_ALL_BITS; - ptr->bits[word_num] = bit_val; - bitmap_element_link (head, ptr); - return true; - } - else + if (ptr != 0) { bool res = (ptr->bits[word_num] & bit_val) == 0; if (res) ptr->bits[word_num] |= bit_val; return res; } + + ptr = bitmap_element_allocate (head); + ptr->indx = bit / BITMAP_ELEMENT_ALL_BITS; + ptr->bits[word_num] = bit_val; + if (!head->tree_form) + bitmap_list_link_element (head, ptr); + else + bitmap_tree_link_element (head, ptr); + return true; } /* Return whether a bit is set within a bitmap. */ @@ -724,13 +1022,14 @@ bitmap_count_bits (const_bitmap a) const bitmap_element *elt; unsigned ix; + gcc_checking_assert (!a->tree_form); for (elt = a->first; elt; elt = elt->next) { for (ix = 0; ix != BITMAP_ELEMENT_WORDS; ix++) { #if GCC_VERSION >= 3400 - /* Note that popcountl matches BITMAP_WORD in type, so the actual size - of BITMAP_WORD is not material. */ + /* Note that popcountl matches BITMAP_WORD in type, + so the actual size of BITMAP_WORD is not material. */ count += __builtin_popcountl (elt->bits[ix]); #else count += bitmap_popcount (elt->bits[ix]); @@ -754,9 +1053,11 @@ bitmap_single_bit_set_p (const_bitmap a) return false; elt = a->first; + /* As there are no completely empty bitmap elements, a second one means we have more than one bit set. */ - if (elt->next != NULL) + if (elt->next != NULL + && (!a->tree_form || elt->prev != NULL)) return false; for (ix = 0; ix != BITMAP_ELEMENT_WORDS; ix++) @@ -788,6 +1089,11 @@ bitmap_first_set_bit (const_bitmap a) unsigned ix; gcc_checking_assert (elt); + + if (a->tree_form) + while (elt->prev) + elt = elt->prev; + bit_no = elt->indx * BITMAP_ELEMENT_ALL_BITS; for (ix = 0; ix != BITMAP_ELEMENT_WORDS; ix++) { @@ -839,8 +1145,11 @@ bitmap_last_set_bit (const_bitmap a) int ix; gcc_checking_assert (elt); + + /* This works for linked-list and binary tree representation alike. */ while (elt->next) elt = elt->next; + bit_no = elt->indx * BITMAP_ELEMENT_ALL_BITS; for (ix = BITMAP_ELEMENT_WORDS - 1; ix >= 0; ix--) { @@ -882,6 +1191,7 @@ bitmap_and (bitmap dst, const_bitmap a, const bitmap_element *b_elt = b->first; bitmap_element *dst_prev = NULL; + gcc_checking_assert (!dst->tree_form && !a->tree_form && !b->tree_form); gcc_assert (dst != a && dst != b); if (a == b) @@ -903,7 +1213,8 @@ bitmap_and (bitmap dst, const_bitmap a, BITMAP_WORD ior = 0; if (!dst_elt) - dst_elt = bitmap_elt_insert_after (dst, dst_prev, a_elt->indx); + dst_elt = bitmap_list_insert_element_after (dst, dst_prev, + a_elt->indx); else dst_elt->indx = a_elt->indx; for (ix = 0; ix < BITMAP_ELEMENT_WORDS; ix++) @@ -940,6 +1251,8 @@ bitmap_and_into (bitmap a, const_bitmap bitmap_element *next; bool changed = false; + gcc_checking_assert (!a->tree_form && !b->tree_form); + if (a == b) return false; @@ -948,7 +1261,7 @@ bitmap_and_into (bitmap a, const_bitmap if (a_elt->indx < b_elt->indx) { next = a_elt->next; - bitmap_element_free (a, a_elt); + bitmap_list_unlink_element (a, a_elt); a_elt = next; changed = true; } @@ -970,7 +1283,7 @@ bitmap_and_into (bitmap a, const_bitmap } next = a_elt->next; if (!ior) - bitmap_element_free (a, a_elt); + bitmap_list_unlink_element (a, a_elt); a_elt = next; b_elt = b_elt->next; } @@ -1012,7 +1325,8 @@ bitmap_elt_copy (bitmap dst, bitmap_elem { changed = true; if (!dst_elt) - dst_elt = bitmap_elt_insert_after (dst, dst_prev, src_elt->indx); + dst_elt = bitmap_list_insert_element_after (dst, dst_prev, + src_elt->indx); else dst_elt->indx = src_elt->indx; memcpy (dst_elt->bits, src_elt->bits, sizeof (dst_elt->bits)); @@ -1034,6 +1348,7 @@ bitmap_and_compl (bitmap dst, const_bitm bitmap_element **dst_prev_pnext = &dst->first; bool changed = false; + gcc_checking_assert (!dst->tree_form && !a->tree_form && !b->tree_form); gcc_assert (dst != a && dst != b); if (a == b) @@ -1082,7 +1397,8 @@ bitmap_and_compl (bitmap dst, const_bitm bool new_element; if (!dst_elt || dst_elt->indx > a_elt->indx) { - dst_elt = bitmap_elt_insert_after (dst, dst_prev, a_elt->indx); + dst_elt = bitmap_list_insert_element_after (dst, dst_prev, + a_elt->indx); new_element = true; } else @@ -1104,7 +1420,7 @@ bitmap_and_compl (bitmap dst, const_bitm else { changed |= !new_element; - bitmap_element_free (dst, dst_elt); + bitmap_list_unlink_element (dst, dst_elt); dst_elt = *dst_prev_pnext; } } @@ -1145,6 +1461,8 @@ bitmap_and_compl_into (bitmap a, const_b bitmap_element *next; BITMAP_WORD changed = 0; + gcc_checking_assert (!a->tree_form && !b->tree_form); + if (a == b) { if (bitmap_empty_p (a)) @@ -1179,7 +1497,7 @@ bitmap_and_compl_into (bitmap a, const_b } next = a_elt->next; if (!ior) - bitmap_element_free (a, a_elt); + bitmap_list_unlink_element (a, a_elt); a_elt = next; b_elt = b_elt->next; } @@ -1197,6 +1515,8 @@ bitmap_set_range (bitmap head, unsigned bitmap_element *elt, *elt_prev; unsigned int i; + gcc_checking_assert (!head->tree_form); + if (!count) return; @@ -1213,7 +1533,7 @@ bitmap_set_range (bitmap head, unsigned { elt = bitmap_element_allocate (head); elt->indx = first_index; - bitmap_element_link (head, elt); + bitmap_list_link_element (head, elt); } gcc_checking_assert (elt->indx == first_index); @@ -1230,7 +1550,7 @@ bitmap_set_range (bitmap head, unsigned unsigned int ix; if (!elt || elt->indx != i) - elt = bitmap_elt_insert_after (head, elt_prev, i); + elt = bitmap_list_insert_element_after (head, elt_prev, i); if (elt_start_bit <= start) { @@ -1296,6 +1616,8 @@ bitmap_clear_range (bitmap head, unsigne unsigned int first_index, end_bit_plus1, last_index; bitmap_element *elt; + gcc_checking_assert (!head->tree_form); + if (!count) return; @@ -1333,7 +1655,7 @@ bitmap_clear_range (bitmap head, unsigne if (elt_start_bit >= start && elt_end_bit_plus1 <= end_bit_plus1) /* Get rid of the entire elt and go to the next one. */ - bitmap_element_free (head, elt); + bitmap_list_unlink_element (head, elt); else { /* Going to have to knock out some bits in this elt. */ @@ -1403,7 +1725,7 @@ bitmap_clear_range (bitmap head, unsigne } /* Check to see if there are any bits left. */ if (clear) - bitmap_element_free (head, elt); + bitmap_list_unlink_element (head, elt); } elt = next_elt; } @@ -1425,6 +1747,7 @@ bitmap_compl_and_into (bitmap a, const_b bitmap_element *a_prev = NULL; bitmap_element *next; + gcc_checking_assert (!a->tree_form && !b->tree_form); gcc_assert (a != b); if (bitmap_empty_p (a)) @@ -1445,13 +1768,13 @@ bitmap_compl_and_into (bitmap a, const_b /* A is before B. Remove A */ next = a_elt->next; a_prev = a_elt->prev; - bitmap_element_free (a, a_elt); + bitmap_list_unlink_element (a, a_elt); a_elt = next; } else if (!a_elt || b_elt->indx < a_elt->indx) { /* B is before A. Copy B. */ - next = bitmap_elt_insert_after (a, a_prev, b_elt->indx); + next = bitmap_list_insert_element_after (a, a_prev, b_elt->indx); memcpy (next->bits, b_elt->bits, sizeof (next->bits)); a_prev = next; b_elt = b_elt->next; @@ -1472,7 +1795,7 @@ bitmap_compl_and_into (bitmap a, const_b } next = a_elt->next; if (!ior) - bitmap_element_free (a, a_elt); + bitmap_list_unlink_element (a, a_elt); else a_prev = a_elt; a_elt = next; @@ -1517,7 +1840,8 @@ bitmap_elt_ior (bitmap dst, bitmap_eleme { changed = true; if (!dst_elt) - dst_elt = bitmap_elt_insert_after (dst, dst_prev, a_elt->indx); + dst_elt = bitmap_list_insert_element_after (dst, dst_prev, + a_elt->indx); else dst_elt->indx = a_elt->indx; for (ix = 0; ix < BITMAP_ELEMENT_WORDS; ix++) @@ -1556,6 +1880,7 @@ bitmap_ior (bitmap dst, const_bitmap a, bitmap_element **dst_prev_pnext = &dst->first; bool changed = false; + gcc_checking_assert (!dst->tree_form && !a->tree_form && !b->tree_form); gcc_assert (dst != a && dst != b); while (a_elt || b_elt) @@ -1602,6 +1927,7 @@ bitmap_ior_into (bitmap a, const_bitmap bitmap_element **a_prev_pnext = &a->first; bool changed = false; + gcc_checking_assert (!a->tree_form && !b->tree_form); if (a == b) return false; @@ -1640,7 +1966,9 @@ bitmap_xor (bitmap dst, const_bitmap a, const bitmap_element *b_elt = b->first; bitmap_element *dst_prev = NULL; + gcc_checking_assert (!dst->tree_form && !a->tree_form && !b->tree_form); gcc_assert (dst != a && dst != b); + if (a == b) { bitmap_clear (dst); @@ -1656,7 +1984,8 @@ bitmap_xor (bitmap dst, const_bitmap a, BITMAP_WORD ior = 0; if (!dst_elt) - dst_elt = bitmap_elt_insert_after (dst, dst_prev, a_elt->indx); + dst_elt = bitmap_list_insert_element_after (dst, dst_prev, + a_elt->indx); else dst_elt->indx = a_elt->indx; for (ix = 0; ix < BITMAP_ELEMENT_WORDS; ix++) @@ -1691,7 +2020,8 @@ bitmap_xor (bitmap dst, const_bitmap a, } if (!dst_elt) - dst_elt = bitmap_elt_insert_after (dst, dst_prev, src->indx); + dst_elt = bitmap_list_insert_element_after (dst, dst_prev, + src->indx); else dst_elt->indx = src->indx; memcpy (dst_elt->bits, src->bits, sizeof (dst_elt->bits)); @@ -1716,6 +2046,8 @@ bitmap_xor_into (bitmap a, const_bitmap const bitmap_element *b_elt = b->first; bitmap_element *a_prev = NULL; + gcc_checking_assert (!a->tree_form && !b->tree_form); + if (a == b) { bitmap_clear (a); @@ -1727,7 +2059,8 @@ bitmap_xor_into (bitmap a, const_bitmap if (!a_elt || b_elt->indx < a_elt->indx) { /* Copy b_elt. */ - bitmap_element *dst = bitmap_elt_insert_after (a, a_prev, b_elt->indx); + bitmap_element *dst = bitmap_list_insert_element_after (a, a_prev, + b_elt->indx); memcpy (dst->bits, b_elt->bits, sizeof (dst->bits)); a_prev = dst; b_elt = b_elt->next; @@ -1755,7 +2088,7 @@ bitmap_xor_into (bitmap a, const_bitmap if (ior) a_prev = a_elt; else - bitmap_element_free (a, a_elt); + bitmap_list_unlink_element (a, a_elt); a_elt = next; } } @@ -1775,6 +2108,8 @@ bitmap_equal_p (const_bitmap a, const_bi const bitmap_element *b_elt; unsigned ix; + gcc_checking_assert (!a->tree_form && !b->tree_form); + for (a_elt = a->first, b_elt = b->first; a_elt && b_elt; a_elt = a_elt->next, b_elt = b_elt->next) @@ -1797,6 +2132,8 @@ bitmap_intersect_p (const_bitmap a, cons const bitmap_element *b_elt; unsigned ix; + gcc_checking_assert (!a->tree_form && !b->tree_form); + for (a_elt = a->first, b_elt = b->first; a_elt && b_elt;) { @@ -1824,6 +2161,9 @@ bitmap_intersect_compl_p (const_bitmap a const bitmap_element *a_elt; const bitmap_element *b_elt; unsigned ix; + + gcc_checking_assert (!a->tree_form && !b->tree_form); + for (a_elt = a->first, b_elt = b->first; a_elt && b_elt;) { @@ -1858,6 +2198,9 @@ bitmap_ior_and_compl (bitmap dst, const_ bitmap_element *dst_prev = NULL; bitmap_element **dst_prev_pnext = &dst->first; + gcc_checking_assert (!dst->tree_form + && !a->tree_form && !b->tree_form + && !kill->tree_form); gcc_assert (dst != a && dst != b && dst != kill); /* Special cases. We don't bother checking for bitmap_equal_p (b, kill). */ @@ -1948,16 +2291,18 @@ bitmap_ior_and_compl (bitmap dst, const_ return changed; } -/* A |= (FROM1 & ~FROM2). Return true if A changes. */ +/* A |= (B & ~C). Return true if A changes. */ bool -bitmap_ior_and_compl_into (bitmap a, const_bitmap from1, const_bitmap from2) +bitmap_ior_and_compl_into (bitmap a, const_bitmap b, const_bitmap c) { bitmap_head tmp; bool changed; + gcc_checking_assert (!a->tree_form && !b->tree_form && !c->tree_form); + bitmap_initialize (&tmp, &bitmap_default_obstack); - bitmap_and_compl (&tmp, from1, from2); + bitmap_and_compl (&tmp, b, c); changed = bitmap_ior_into (a, &tmp); bitmap_clear (&tmp); @@ -1978,6 +2323,8 @@ bitmap_ior_and_into (bitmap a, const_bit bool changed = false; unsigned ix; + gcc_checking_assert (!a->tree_form && !b->tree_form && !c->tree_form); + if (b == c) return bitmap_ior_into (a, b); if (bitmap_empty_p (b) || bitmap_empty_p (c)) @@ -2044,6 +2391,7 @@ bitmap_ior_and_into (bitmap a, const_bit } /* Compute hash of bitmap (for purposes of hashing). */ + hashval_t bitmap_hash (const_bitmap head) { @@ -2051,6 +2399,8 @@ bitmap_hash (const_bitmap head) BITMAP_WORD hash = 0; int ix; + gcc_checking_assert (!head->tree_form); + for (ptr = head->first; ptr; ptr = ptr->next) { hash ^= ptr->indx; @@ -2064,9 +2414,13 @@ bitmap_hash (const_bitmap head) /* Debugging function to print out the contents of a bitmap. */ DEBUG_FUNCTION void -debug_bitmap_file (FILE *file, const_bitmap head) +debug_bitmap_file (FILE *file, bitmap head) { const bitmap_element *ptr; + bool tree_form = head->tree_form; + + if (tree_form) + bitmap_list_view (head); fprintf (file, "\nfirst = " HOST_PTR_PRINTF " current = " HOST_PTR_PRINTF " indx = %u\n", @@ -2098,13 +2452,16 @@ debug_bitmap_file (FILE *file, const_bit fprintf (file, " }\n"); } + + if (tree_form) + bitmap_tree_view (head); } /* Function to be called from the debugger to print the contents of a bitmap. */ DEBUG_FUNCTION void -debug_bitmap (const_bitmap head) +debug_bitmap (bitmap head) { debug_bitmap_file (stdout, head); } @@ -2113,11 +2470,15 @@ debug_bitmap (const_bitmap head) it does not print anything but the bits. */ DEBUG_FUNCTION void -bitmap_print (FILE *file, const_bitmap head, const char *prefix, const char *suffix) +bitmap_print (FILE *file, bitmap head, const char *prefix, const char *suffix) { const char *comma = ""; unsigned i; bitmap_iterator bi; + bool tree_form = head->tree_form; + + if (tree_form) + bitmap_list_view (head); fputs (prefix, file); EXECUTE_IF_SET_IN_BITMAP (head, 0, i, bi) @@ -2126,6 +2487,9 @@ bitmap_print (FILE *file, const_bitmap h comma = ", "; } fputs (suffix, file); + + if (tree_form) + bitmap_tree_view (head); }