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Diffstat (limited to 'lib/gcc/arm-none-eabi/13.2.1/plugin/include/bitmap.h')
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diff --git a/lib/gcc/arm-none-eabi/13.2.1/plugin/include/bitmap.h b/lib/gcc/arm-none-eabi/13.2.1/plugin/include/bitmap.h new file mode 100644 index 0000000..43337d2 --- /dev/null +++ b/lib/gcc/arm-none-eabi/13.2.1/plugin/include/bitmap.h @@ -0,0 +1,1089 @@ +/* Functions to support general ended bitmaps. + Copyright (C) 1997-2023 Free Software Foundation, Inc. + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation; either version 3, or (at your option) any later +version. + +GCC is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or +FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the file COPYING3. If not see +<http://www.gnu.org/licenses/>. */ + +#ifndef GCC_BITMAP_H +#define GCC_BITMAP_H + +/* Implementation of sparse integer sets as a linked list or tree. + + This sparse set representation is suitable for sparse sets with an + unknown (a priori) universe. + + Sets are represented as double-linked lists of container nodes of + type "struct bitmap_element" 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) + - the position for I within element is I % (bits per element) + + This representation is very space-efficient for large sparse sets, and + the size of the set can be changed dynamically without much overhead. + An important parameter is the number of bits per element. In this + implementation, there are 128 bits per element. This results in a + high storage overhead *per element*, but a small overall overhead if + the set is very sparse. + + 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: + + * from list to tree view : bitmap_tree_view + * from tree to list view : bitmap_list_view + + 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 in + list view: + + * clear : bitmap_clear + * smallest_member : bitmap_first_set_bit + * choose_one : (not implemented, but could be + in constant time) + + The following operations can be performed in O(E) time worst-case in + list view (with E the number of elements in the linked list), but in + O(1) time with a suitable access patterns: + + * member_p : bitmap_bit_p + * 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 in list view: + + * cardinality : bitmap_count_bits + * 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 + + In tree view the following operations can all be performed in O(log E) + amortized time with O(E) worst-case behavior. + + * smallest_member + * largest_member + * set_size + * member_p + * add_member + * remove_member + + Additionally, the linked-list sparse set representation supports + enumeration of the members in O(E) time: + + * forall : EXECUTE_IF_SET_IN_BITMAP + * set_copy : bitmap_copy + * set_intersection : bitmap_intersect_p / + bitmap_and / bitmap_and_into / + EXECUTE_IF_AND_IN_BITMAP + * set_union : bitmap_ior / bitmap_ior_into + * set_difference : bitmap_intersect_compl_p / + bitmap_and_comp / bitmap_and_comp_into / + EXECUTE_IF_AND_COMPL_IN_BITMAP + * set_disjuction : bitmap_xor_comp / bitmap_xor_comp_into + * set_compare : bitmap_equal_p + + Some operations on 3 sets that occur frequently in data flow problems + are also implemented: + + * A | (B & C) : bitmap_ior_and_into + * A | (B & ~C) : bitmap_ior_and_compl / + bitmap_ior_and_compl_into + + + 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. + + 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). + + The following operations can always be performed in O(1) time: + + * 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 "obstack.h" +#include "array-traits.h" + +/* Bitmap memory usage. */ +class bitmap_usage: public mem_usage +{ +public: + /* Default contructor. */ + bitmap_usage (): m_nsearches (0), m_search_iter (0) {} + /* Constructor. */ + bitmap_usage (size_t allocated, size_t times, size_t peak, + uint64_t nsearches, uint64_t search_iter) + : mem_usage (allocated, times, peak), + m_nsearches (nsearches), m_search_iter (search_iter) {} + + /* Sum the usage with SECOND usage. */ + bitmap_usage + operator+ (const bitmap_usage &second) + { + return bitmap_usage (m_allocated + second.m_allocated, + m_times + second.m_times, + m_peak + second.m_peak, + m_nsearches + second.m_nsearches, + m_search_iter + second.m_search_iter); + } + + /* Dump usage coupled to LOC location, where TOTAL is sum of all rows. */ + inline void + dump (mem_location *loc, const mem_usage &total) const + { + char *location_string = loc->to_string (); + + fprintf (stderr, "%-48s " PRsa (9) ":%5.1f%%" + PRsa (9) PRsa (9) ":%5.1f%%" + PRsa (11) PRsa (11) "%10s\n", + location_string, SIZE_AMOUNT (m_allocated), + get_percent (m_allocated, total.m_allocated), + SIZE_AMOUNT (m_peak), SIZE_AMOUNT (m_times), + get_percent (m_times, total.m_times), + SIZE_AMOUNT (m_nsearches), SIZE_AMOUNT (m_search_iter), + loc->m_ggc ? "ggc" : "heap"); + + free (location_string); + } + + /* Dump header with NAME. */ + static inline void + dump_header (const char *name) + { + fprintf (stderr, "%-48s %11s%16s%17s%12s%12s%10s\n", name, "Leak", "Peak", + "Times", "N searches", "Search iter", "Type"); + } + + /* Number search operations. */ + uint64_t m_nsearches; + /* Number of search iterations. */ + uint64_t m_search_iter; +}; + +/* Bitmap memory description. */ +extern mem_alloc_description<bitmap_usage> bitmap_mem_desc; + +/* Fundamental storage type for bitmap. */ + +typedef unsigned long BITMAP_WORD; +/* BITMAP_WORD_BITS needs to be unsigned, but cannot contain casts as + it is used in preprocessor directives -- hence the 1u. */ +#define BITMAP_WORD_BITS (CHAR_BIT * SIZEOF_LONG * 1u) + +/* Number of words to use for each element in the linked list. */ + +#ifndef BITMAP_ELEMENT_WORDS +#define BITMAP_ELEMENT_WORDS ((128 + BITMAP_WORD_BITS - 1) / BITMAP_WORD_BITS) +#endif + +/* Number of bits in each actual element of a bitmap. */ + +#define BITMAP_ELEMENT_ALL_BITS (BITMAP_ELEMENT_WORDS * BITMAP_WORD_BITS) + +/* Obstack for allocating bitmaps and elements from. */ +struct bitmap_obstack { + struct bitmap_element *elements; + bitmap_head *heads; + struct obstack obstack; +}; + +/* Bitmap set element. We use a linked list to hold only the bits that + are set. This allows for use to grow the bitset dynamically without + having to realloc and copy a giant bit array. + + The free list is implemented as a list of lists. There is one + outer list connected together by prev fields. Each element of that + outer is an inner list (that may consist only of the outer list + element) that are connected by the next fields. The prev pointer + is undefined for interior elements. This allows + bitmap_elt_clear_from to be implemented in unit time rather than + linear in the number of elements to be freed. */ + +struct GTY((chain_next ("%h.next"))) bitmap_element { + /* In list form, the next element in the linked list; + in tree form, the left child node in the tree. */ + struct bitmap_element *next; + /* In list form, the previous element in the linked list; + in tree form, the right child node in the tree. */ + struct bitmap_element *prev; + /* regno/BITMAP_ELEMENT_ALL_BITS. */ + unsigned int indx; + /* Bits that are set, counting from INDX, inclusive */ + BITMAP_WORD bits[BITMAP_ELEMENT_WORDS]; +}; + +/* Head of bitmap linked list. The 'current' member points to something + already pointed to by the chain started by first, so GTY((skip)) it. */ + +class GTY(()) bitmap_head { +public: + static bitmap_obstack crashme; + /* Poison obstack to not make it not a valid initialized GC bitmap. */ + CONSTEXPR bitmap_head() + : indx (0), tree_form (false), padding (0), alloc_descriptor (0), first (NULL), + current (NULL), obstack (&crashme) + {} + /* Index of last element looked at. */ + unsigned int indx; + /* False if the bitmap is in list form; true if the bitmap is in tree form. + Bitmap iterators only work on bitmaps in list form. */ + unsigned tree_form: 1; + /* Next integer is shifted, so padding is needed. */ + unsigned padding: 2; + /* Bitmap UID used for memory allocation statistics. */ + unsigned alloc_descriptor: 29; + /* 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 * GTY((skip(""))) obstack; + + /* Dump bitmap. */ + void dump (); + + /* Get bitmap descriptor UID casted to an unsigned integer pointer. + Shift the descriptor because pointer_hash<Type>::hash is + doing >> 3 shift operation. */ + unsigned *get_descriptor () + { + return (unsigned *)(ptrdiff_t)(alloc_descriptor << 3); + } +}; + +/* Global data */ +extern bitmap_element bitmap_zero_bits; /* Zero bitmap element */ +extern bitmap_obstack bitmap_default_obstack; /* Default bitmap obstack */ + +/* Change the view of the bitmap to list, or tree. */ +void bitmap_list_view (bitmap); +void bitmap_tree_view (bitmap); + +/* Clear a bitmap by freeing up the linked list. */ +extern void bitmap_clear (bitmap); + +/* Copy a bitmap to another bitmap. */ +extern void bitmap_copy (bitmap, const_bitmap); + +/* Move a bitmap to another bitmap. */ +extern void bitmap_move (bitmap, bitmap); + +/* True if two bitmaps are identical. */ +extern bool bitmap_equal_p (const_bitmap, const_bitmap); + +/* True if the bitmaps intersect (their AND is non-empty). */ +extern bool bitmap_intersect_p (const_bitmap, const_bitmap); + +/* True if the complement of the second intersects the first (their + AND_COMPL is non-empty). */ +extern bool bitmap_intersect_compl_p (const_bitmap, const_bitmap); + +/* True if MAP is an empty bitmap. */ +inline bool bitmap_empty_p (const_bitmap map) +{ + return !map->first; +} + +/* True if the bitmap has only a single bit set. */ +extern bool bitmap_single_bit_set_p (const_bitmap); + +/* Count the number of bits set in the bitmap. */ +extern unsigned long bitmap_count_bits (const_bitmap); + +/* Count the number of unique bits set across the two bitmaps. */ +extern unsigned long bitmap_count_unique_bits (const_bitmap, const_bitmap); + +/* Boolean operations on bitmaps. The _into variants are two operand + versions that modify the first source operand. The other variants + are three operand versions that to not destroy the source bitmaps. + The operations supported are &, & ~, |, ^. */ +extern void bitmap_and (bitmap, const_bitmap, const_bitmap); +extern bool bitmap_and_into (bitmap, const_bitmap); +extern bool bitmap_and_compl (bitmap, const_bitmap, const_bitmap); +extern bool bitmap_and_compl_into (bitmap, const_bitmap); +#define bitmap_compl_and(DST, A, B) bitmap_and_compl (DST, B, A) +extern void bitmap_compl_and_into (bitmap, const_bitmap); +extern void bitmap_clear_range (bitmap, unsigned int, unsigned int); +extern void bitmap_set_range (bitmap, unsigned int, unsigned int); +extern bool bitmap_ior (bitmap, const_bitmap, const_bitmap); +extern bool bitmap_ior_into (bitmap, const_bitmap); +extern bool bitmap_ior_into_and_free (bitmap, bitmap *); +extern void bitmap_xor (bitmap, const_bitmap, const_bitmap); +extern void bitmap_xor_into (bitmap, const_bitmap); + +/* DST = A | (B & C). Return true if DST changes. */ +extern bool bitmap_ior_and_into (bitmap DST, const_bitmap B, const_bitmap C); +/* DST = A | (B & ~C). Return true if DST changes. */ +extern bool bitmap_ior_and_compl (bitmap DST, const_bitmap A, + const_bitmap B, const_bitmap C); +/* A |= (B & ~C). Return true if A changes. */ +extern bool bitmap_ior_and_compl_into (bitmap A, + const_bitmap B, const_bitmap C); + +/* Clear a single bit in a bitmap. Return true if the bit changed. */ +extern bool bitmap_clear_bit (bitmap, int); + +/* Set a single bit in a bitmap. Return true if the bit changed. */ +extern bool bitmap_set_bit (bitmap, int); + +/* Return true if a bit is set in a bitmap. */ +extern bool bitmap_bit_p (const_bitmap, int); + +/* Set and get multiple bit values in a sparse bitmap. This allows a bitmap to + function as a sparse array of bit patterns where the patterns are + multiples of power of 2. This is more efficient than performing this as + multiple individual operations. */ +void bitmap_set_aligned_chunk (bitmap, unsigned int, unsigned int, BITMAP_WORD); +BITMAP_WORD bitmap_get_aligned_chunk (const_bitmap, unsigned int, unsigned int); + +/* Debug functions to print a bitmap. */ +extern void debug_bitmap (const_bitmap); +extern void debug_bitmap_file (FILE *, const_bitmap); + +/* Print a bitmap. */ +extern void bitmap_print (FILE *, const_bitmap, const char *, const char *); + +/* Initialize and release a bitmap obstack. */ +extern void bitmap_obstack_initialize (bitmap_obstack *); +extern void bitmap_obstack_release (bitmap_obstack *); +extern void bitmap_register (bitmap MEM_STAT_DECL); +extern void dump_bitmap_statistics (void); + +/* Initialize a bitmap header. OBSTACK indicates the bitmap obstack + to allocate from, NULL for GC'd bitmap. */ + +inline void +bitmap_initialize (bitmap head, bitmap_obstack *obstack CXX_MEM_STAT_INFO) +{ + head->first = head->current = NULL; + head->indx = head->tree_form = 0; + head->padding = 0; + head->alloc_descriptor = 0; + head->obstack = obstack; + if (GATHER_STATISTICS) + bitmap_register (head PASS_MEM_STAT); +} + +/* Release a bitmap (but not its head). This is suitable for pairing with + bitmap_initialize. */ + +inline void +bitmap_release (bitmap head) +{ + bitmap_clear (head); + /* Poison the obstack pointer so the obstack can be safely released. + Do not zero it as the bitmap then becomes initialized GC. */ + head->obstack = &bitmap_head::crashme; +} + +/* Allocate and free bitmaps from obstack, malloc and gc'd memory. */ +extern bitmap bitmap_alloc (bitmap_obstack *obstack CXX_MEM_STAT_INFO); +#define BITMAP_ALLOC bitmap_alloc +extern bitmap bitmap_gc_alloc (ALONE_CXX_MEM_STAT_INFO); +#define BITMAP_GGC_ALLOC bitmap_gc_alloc +extern void bitmap_obstack_free (bitmap); + +/* A few compatibility/functions macros for compatibility with sbitmaps */ +inline void dump_bitmap (FILE *file, const_bitmap map) +{ + bitmap_print (file, map, "", "\n"); +} +extern void debug (const bitmap_head &ref); +extern void debug (const bitmap_head *ptr); + +extern unsigned bitmap_first_set_bit (const_bitmap); +extern unsigned bitmap_last_set_bit (const_bitmap); + +/* Compute bitmap hash (for purposes of hashing etc.) */ +extern hashval_t bitmap_hash (const_bitmap); + +/* Do any cleanup needed on a bitmap when it is no longer used. */ +#define BITMAP_FREE(BITMAP) \ + ((void) (bitmap_obstack_free ((bitmap) BITMAP), (BITMAP) = (bitmap) NULL)) + +/* Iterator for bitmaps. */ + +struct bitmap_iterator +{ + /* Pointer to the current bitmap element. */ + bitmap_element *elt1; + + /* Pointer to 2nd bitmap element when two are involved. */ + bitmap_element *elt2; + + /* Word within the current element. */ + unsigned word_no; + + /* Contents of the actually processed word. When finding next bit + it is shifted right, so that the actual bit is always the least + significant bit of ACTUAL. */ + BITMAP_WORD bits; +}; + +/* Initialize a single bitmap iterator. START_BIT is the first bit to + iterate from. */ + +inline void +bmp_iter_set_init (bitmap_iterator *bi, const_bitmap map, + unsigned start_bit, unsigned *bit_no) +{ + 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) + { + if (!bi->elt1) + { + bi->elt1 = &bitmap_zero_bits; + break; + } + + if (bi->elt1->indx >= start_bit / BITMAP_ELEMENT_ALL_BITS) + break; + bi->elt1 = bi->elt1->next; + } + + /* We might have gone past the start bit, so reinitialize it. */ + if (bi->elt1->indx != start_bit / BITMAP_ELEMENT_ALL_BITS) + start_bit = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; + + /* Initialize for what is now start_bit. */ + bi->word_no = start_bit / BITMAP_WORD_BITS % BITMAP_ELEMENT_WORDS; + bi->bits = bi->elt1->bits[bi->word_no]; + bi->bits >>= start_bit % BITMAP_WORD_BITS; + + /* If this word is zero, we must make sure we're not pointing at the + first bit, otherwise our incrementing to the next word boundary + will fail. It won't matter if this increment moves us into the + next word. */ + start_bit += !bi->bits; + + *bit_no = start_bit; +} + +/* Initialize an iterator to iterate over the intersection of two + bitmaps. START_BIT is the bit to commence from. */ + +inline void +bmp_iter_and_init (bitmap_iterator *bi, const_bitmap map1, const_bitmap map2, + unsigned start_bit, unsigned *bit_no) +{ + 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) + { + if (!bi->elt1) + { + bi->elt2 = NULL; + break; + } + + if (bi->elt1->indx >= start_bit / BITMAP_ELEMENT_ALL_BITS) + break; + bi->elt1 = bi->elt1->next; + } + + /* Advance elt2 until it is not before elt1. */ + while (1) + { + if (!bi->elt2) + { + bi->elt1 = bi->elt2 = &bitmap_zero_bits; + break; + } + + if (bi->elt2->indx >= bi->elt1->indx) + break; + bi->elt2 = bi->elt2->next; + } + + /* If we're at the same index, then we have some intersecting bits. */ + if (bi->elt1->indx == bi->elt2->indx) + { + /* We might have advanced beyond the start_bit, so reinitialize + for that. */ + if (bi->elt1->indx != start_bit / BITMAP_ELEMENT_ALL_BITS) + start_bit = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; + + bi->word_no = start_bit / BITMAP_WORD_BITS % BITMAP_ELEMENT_WORDS; + bi->bits = bi->elt1->bits[bi->word_no] & bi->elt2->bits[bi->word_no]; + bi->bits >>= start_bit % BITMAP_WORD_BITS; + } + else + { + /* Otherwise we must immediately advance elt1, so initialize for + that. */ + bi->word_no = BITMAP_ELEMENT_WORDS - 1; + bi->bits = 0; + } + + /* If this word is zero, we must make sure we're not pointing at the + first bit, otherwise our incrementing to the next word boundary + will fail. It won't matter if this increment moves us into the + next word. */ + start_bit += !bi->bits; + + *bit_no = start_bit; +} + +/* Initialize an iterator to iterate over the bits in MAP1 & ~MAP2. */ + +inline void +bmp_iter_and_compl_init (bitmap_iterator *bi, + const_bitmap map1, const_bitmap map2, + unsigned start_bit, unsigned *bit_no) +{ + 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) + { + if (!bi->elt1) + { + bi->elt1 = &bitmap_zero_bits; + break; + } + + if (bi->elt1->indx >= start_bit / BITMAP_ELEMENT_ALL_BITS) + break; + bi->elt1 = bi->elt1->next; + } + + /* Advance elt2 until it is not before elt1. */ + while (bi->elt2 && bi->elt2->indx < bi->elt1->indx) + bi->elt2 = bi->elt2->next; + + /* We might have advanced beyond the start_bit, so reinitialize for + that. */ + if (bi->elt1->indx != start_bit / BITMAP_ELEMENT_ALL_BITS) + start_bit = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; + + bi->word_no = start_bit / BITMAP_WORD_BITS % BITMAP_ELEMENT_WORDS; + bi->bits = bi->elt1->bits[bi->word_no]; + if (bi->elt2 && bi->elt1->indx == bi->elt2->indx) + bi->bits &= ~bi->elt2->bits[bi->word_no]; + bi->bits >>= start_bit % BITMAP_WORD_BITS; + + /* If this word is zero, we must make sure we're not pointing at the + first bit, otherwise our incrementing to the next word boundary + will fail. It won't matter if this increment moves us into the + next word. */ + start_bit += !bi->bits; + + *bit_no = start_bit; +} + +/* Advance to the next bit in BI. We don't advance to the next + nonzero bit yet. */ + +inline void +bmp_iter_next (bitmap_iterator *bi, unsigned *bit_no) +{ + bi->bits >>= 1; + *bit_no += 1; +} + +/* Advance to first set bit in BI. */ + +inline void +bmp_iter_next_bit (bitmap_iterator * bi, unsigned *bit_no) +{ +#if (GCC_VERSION >= 3004) + { + unsigned int n = __builtin_ctzl (bi->bits); + gcc_assert (sizeof (unsigned long) == sizeof (BITMAP_WORD)); + bi->bits >>= n; + *bit_no += n; + } +#else + while (!(bi->bits & 1)) + { + bi->bits >>= 1; + *bit_no += 1; + } +#endif +} + +/* Advance to the next nonzero bit of a single bitmap, we will have + already advanced past the just iterated bit. Return true if there + is a bit to iterate. */ + +inline bool +bmp_iter_set (bitmap_iterator *bi, unsigned *bit_no) +{ + /* If our current word is nonzero, it contains the bit we want. */ + if (bi->bits) + { + next_bit: + bmp_iter_next_bit (bi, bit_no); + return true; + } + + /* Round up to the word boundary. We might have just iterated past + the end of the last word, hence the -1. It is not possible for + bit_no to point at the beginning of the now last word. */ + *bit_no = ((*bit_no + BITMAP_WORD_BITS - 1) + / BITMAP_WORD_BITS * BITMAP_WORD_BITS); + bi->word_no++; + + while (1) + { + /* Find the next nonzero word in this elt. */ + while (bi->word_no != BITMAP_ELEMENT_WORDS) + { + bi->bits = bi->elt1->bits[bi->word_no]; + if (bi->bits) + goto next_bit; + *bit_no += BITMAP_WORD_BITS; + bi->word_no++; + } + + /* Make sure we didn't remove the element while iterating. */ + gcc_checking_assert (bi->elt1->indx != -1U); + + /* Advance to the next element. */ + bi->elt1 = bi->elt1->next; + if (!bi->elt1) + return false; + *bit_no = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; + bi->word_no = 0; + } +} + +/* Advance to the next nonzero bit of an intersecting pair of + bitmaps. We will have already advanced past the just iterated bit. + Return true if there is a bit to iterate. */ + +inline bool +bmp_iter_and (bitmap_iterator *bi, unsigned *bit_no) +{ + /* If our current word is nonzero, it contains the bit we want. */ + if (bi->bits) + { + next_bit: + bmp_iter_next_bit (bi, bit_no); + return true; + } + + /* Round up to the word boundary. We might have just iterated past + the end of the last word, hence the -1. It is not possible for + bit_no to point at the beginning of the now last word. */ + *bit_no = ((*bit_no + BITMAP_WORD_BITS - 1) + / BITMAP_WORD_BITS * BITMAP_WORD_BITS); + bi->word_no++; + + while (1) + { + /* Find the next nonzero word in this elt. */ + while (bi->word_no != BITMAP_ELEMENT_WORDS) + { + bi->bits = bi->elt1->bits[bi->word_no] & bi->elt2->bits[bi->word_no]; + if (bi->bits) + goto next_bit; + *bit_no += BITMAP_WORD_BITS; + bi->word_no++; + } + + /* Advance to the next identical element. */ + do + { + /* Make sure we didn't remove the element while iterating. */ + gcc_checking_assert (bi->elt1->indx != -1U); + + /* Advance elt1 while it is less than elt2. We always want + to advance one elt. */ + do + { + bi->elt1 = bi->elt1->next; + if (!bi->elt1) + return false; + } + while (bi->elt1->indx < bi->elt2->indx); + + /* Make sure we didn't remove the element while iterating. */ + gcc_checking_assert (bi->elt2->indx != -1U); + + /* Advance elt2 to be no less than elt1. This might not + advance. */ + while (bi->elt2->indx < bi->elt1->indx) + { + bi->elt2 = bi->elt2->next; + if (!bi->elt2) + return false; + } + } + while (bi->elt1->indx != bi->elt2->indx); + + *bit_no = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; + bi->word_no = 0; + } +} + +/* Advance to the next nonzero bit in the intersection of + complemented bitmaps. We will have already advanced past the just + iterated bit. */ + +inline bool +bmp_iter_and_compl (bitmap_iterator *bi, unsigned *bit_no) +{ + /* If our current word is nonzero, it contains the bit we want. */ + if (bi->bits) + { + next_bit: + bmp_iter_next_bit (bi, bit_no); + return true; + } + + /* Round up to the word boundary. We might have just iterated past + the end of the last word, hence the -1. It is not possible for + bit_no to point at the beginning of the now last word. */ + *bit_no = ((*bit_no + BITMAP_WORD_BITS - 1) + / BITMAP_WORD_BITS * BITMAP_WORD_BITS); + bi->word_no++; + + while (1) + { + /* Find the next nonzero word in this elt. */ + while (bi->word_no != BITMAP_ELEMENT_WORDS) + { + bi->bits = bi->elt1->bits[bi->word_no]; + if (bi->elt2 && bi->elt2->indx == bi->elt1->indx) + bi->bits &= ~bi->elt2->bits[bi->word_no]; + if (bi->bits) + goto next_bit; + *bit_no += BITMAP_WORD_BITS; + bi->word_no++; + } + + /* Make sure we didn't remove the element while iterating. */ + gcc_checking_assert (bi->elt1->indx != -1U); + + /* Advance to the next element of elt1. */ + bi->elt1 = bi->elt1->next; + if (!bi->elt1) + return false; + + /* Make sure we didn't remove the element while iterating. */ + gcc_checking_assert (! bi->elt2 || bi->elt2->indx != -1U); + + /* Advance elt2 until it is no less than elt1. */ + while (bi->elt2 && bi->elt2->indx < bi->elt1->indx) + bi->elt2 = bi->elt2->next; + + *bit_no = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; + bi->word_no = 0; + } +} + +/* If you are modifying a bitmap you are currently iterating over you + have to ensure to + - never remove the current bit; + - if you set or clear a bit before the current bit this operation + will not affect the set of bits you are visiting during the iteration; + - if you set or clear a bit after the current bit it is unspecified + whether that affects the set of bits you are visiting during the + iteration. + If you want to remove the current bit you can delay this to the next + iteration (and after the iteration in case the last iteration is + affected). */ + +/* Loop over all bits set in BITMAP, starting with MIN and setting + BITNUM to the bit number. ITER is a bitmap iterator. BITNUM + should be treated as a read-only variable as it contains loop + state. */ + +#ifndef EXECUTE_IF_SET_IN_BITMAP +/* See sbitmap.h for the other definition of EXECUTE_IF_SET_IN_BITMAP. */ +#define EXECUTE_IF_SET_IN_BITMAP(BITMAP, MIN, BITNUM, ITER) \ + for (bmp_iter_set_init (&(ITER), (BITMAP), (MIN), &(BITNUM)); \ + bmp_iter_set (&(ITER), &(BITNUM)); \ + bmp_iter_next (&(ITER), &(BITNUM))) +#endif + +/* Loop over all the bits set in BITMAP1 & BITMAP2, starting with MIN + and setting BITNUM to the bit number. ITER is a bitmap iterator. + BITNUM should be treated as a read-only variable as it contains + loop state. */ + +#define EXECUTE_IF_AND_IN_BITMAP(BITMAP1, BITMAP2, MIN, BITNUM, ITER) \ + for (bmp_iter_and_init (&(ITER), (BITMAP1), (BITMAP2), (MIN), \ + &(BITNUM)); \ + bmp_iter_and (&(ITER), &(BITNUM)); \ + bmp_iter_next (&(ITER), &(BITNUM))) + +/* Loop over all the bits set in BITMAP1 & ~BITMAP2, starting with MIN + and setting BITNUM to the bit number. ITER is a bitmap iterator. + BITNUM should be treated as a read-only variable as it contains + loop state. */ + +#define EXECUTE_IF_AND_COMPL_IN_BITMAP(BITMAP1, BITMAP2, MIN, BITNUM, ITER) \ + for (bmp_iter_and_compl_init (&(ITER), (BITMAP1), (BITMAP2), (MIN), \ + &(BITNUM)); \ + bmp_iter_and_compl (&(ITER), &(BITNUM)); \ + bmp_iter_next (&(ITER), &(BITNUM))) + +/* A class that ties the lifetime of a bitmap to its scope. */ +class auto_bitmap +{ + public: + auto_bitmap (ALONE_CXX_MEM_STAT_INFO) + { bitmap_initialize (&m_bits, &bitmap_default_obstack PASS_MEM_STAT); } + explicit auto_bitmap (bitmap_obstack *o CXX_MEM_STAT_INFO) + { bitmap_initialize (&m_bits, o PASS_MEM_STAT); } + ~auto_bitmap () { bitmap_clear (&m_bits); } + // Allow calling bitmap functions on our bitmap. + operator bitmap () { return &m_bits; } + + private: + // Prevent making a copy that references our bitmap. + auto_bitmap (const auto_bitmap &); + auto_bitmap &operator = (const auto_bitmap &); + auto_bitmap (auto_bitmap &&); + auto_bitmap &operator = (auto_bitmap &&); + + bitmap_head m_bits; +}; + +extern void debug (const auto_bitmap &ref); +extern void debug (const auto_bitmap *ptr); + +/* Base class for bitmap_view; see there for details. */ +template<typename T, typename Traits = array_traits<T> > +class base_bitmap_view +{ +public: + typedef typename Traits::element_type array_element_type; + + base_bitmap_view (const T &, bitmap_element *); + operator const_bitmap () const { return &m_head; } + +private: + base_bitmap_view (const base_bitmap_view &); + + bitmap_head m_head; +}; + +/* Provides a read-only bitmap view of a single integer bitmask or a + constant-sized array of integer bitmasks, or of a wrapper around such + bitmasks. */ +template<typename T, typename Traits> +class bitmap_view<T, Traits, true> : public base_bitmap_view<T, Traits> +{ +public: + bitmap_view (const T &array) + : base_bitmap_view<T, Traits> (array, m_bitmap_elements) {} + +private: + /* How many bitmap_elements we need to hold a full T. */ + static const size_t num_bitmap_elements + = CEIL (CHAR_BIT + * sizeof (typename Traits::element_type) + * Traits::constant_size, + BITMAP_ELEMENT_ALL_BITS); + bitmap_element m_bitmap_elements[num_bitmap_elements]; +}; + +/* Initialize the view for array ARRAY, using the array of bitmap + elements in BITMAP_ELEMENTS (which is known to contain enough + entries). */ +template<typename T, typename Traits> +base_bitmap_view<T, Traits>::base_bitmap_view (const T &array, + bitmap_element *bitmap_elements) +{ + m_head.obstack = NULL; + + /* The code currently assumes that each element of ARRAY corresponds + to exactly one bitmap_element. */ + const size_t array_element_bits = CHAR_BIT * sizeof (array_element_type); + STATIC_ASSERT (BITMAP_ELEMENT_ALL_BITS % array_element_bits == 0); + size_t array_step = BITMAP_ELEMENT_ALL_BITS / array_element_bits; + size_t array_size = Traits::size (array); + + /* Process each potential bitmap_element in turn. The loop is written + this way rather than per array element because usually there are + only a small number of array elements per bitmap element (typically + two or four). The inner loops should therefore unroll completely. */ + const array_element_type *array_elements = Traits::base (array); + unsigned int indx = 0; + for (size_t array_base = 0; + array_base < array_size; + array_base += array_step, indx += 1) + { + /* How many array elements are in this particular bitmap_element. */ + unsigned int array_count + = (STATIC_CONSTANT_P (array_size % array_step == 0) + ? array_step : MIN (array_step, array_size - array_base)); + + /* See whether we need this bitmap element. */ + array_element_type ior = array_elements[array_base]; + for (size_t i = 1; i < array_count; ++i) + ior |= array_elements[array_base + i]; + if (ior == 0) + continue; + + /* Grab the next bitmap element and chain it. */ + bitmap_element *bitmap_element = bitmap_elements++; + if (m_head.current) + m_head.current->next = bitmap_element; + else + m_head.first = bitmap_element; + bitmap_element->prev = m_head.current; + bitmap_element->next = NULL; + bitmap_element->indx = indx; + m_head.current = bitmap_element; + m_head.indx = indx; + + /* Fill in the bits of the bitmap element. */ + if (array_element_bits < BITMAP_WORD_BITS) + { + /* Multiple array elements fit in one element of + bitmap_element->bits. */ + size_t array_i = array_base; + for (unsigned int word_i = 0; word_i < BITMAP_ELEMENT_WORDS; + ++word_i) + { + BITMAP_WORD word = 0; + for (unsigned int shift = 0; + shift < BITMAP_WORD_BITS && array_i < array_size; + shift += array_element_bits) + word |= array_elements[array_i++] << shift; + bitmap_element->bits[word_i] = word; + } + } + else + { + /* Array elements are the same size as elements of + bitmap_element->bits, or are an exact multiple of that size. */ + unsigned int word_i = 0; + for (unsigned int i = 0; i < array_count; ++i) + for (unsigned int shift = 0; shift < array_element_bits; + shift += BITMAP_WORD_BITS) + bitmap_element->bits[word_i++] + = array_elements[array_base + i] >> shift; + while (word_i < BITMAP_ELEMENT_WORDS) + bitmap_element->bits[word_i++] = 0; + } + } +} + +#endif /* GCC_BITMAP_H */ |