1 /* Define per-register tables for data flow info and register allocation.
2 Copyright (C) 2007 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
28 /* Gives the number of consecutive hard registers needed by that
32 /* Number of calls crossed by each allocno. */
35 /* Estimated frequency of crossing call by each allocno. */
36 int freq_calls_crossed;
38 /* Number of calls that might throw crossed by each allocno. */
39 int throwing_calls_crossed;
41 /* Number of refs to each allocno. */
44 /* Frequency of uses of each allocno. */
47 /* Guess at live length of each allocno.
48 This is actually the max of the live lengths of the regs. */
51 /* Set of hard regs conflicting with allocno N. */
53 HARD_REG_SET hard_reg_conflicts;
55 /* Set of hard regs preferred by allocno N.
56 This is used to make allocnos go into regs that are copied to or from them,
57 when possible, to reduce register shuffling. */
59 HARD_REG_SET hard_reg_preferences;
61 /* Similar, but just counts register preferences made in simple copy
62 operations, rather than arithmetic. These are given priority because
63 we can always eliminate an insn by using these, but using a register
64 in the above list won't always eliminate an insn. */
66 HARD_REG_SET hard_reg_copy_preferences;
68 /* Similar to hard_reg_preferences, but includes bits for subsequent
69 registers when an allocno is multi-word. The above variable is used for
70 allocation while this is used to build reg_someone_prefers, below. */
72 HARD_REG_SET hard_reg_full_preferences;
74 /* Set of hard registers that some later allocno has a preference for. */
76 HARD_REG_SET regs_someone_prefers;
79 /* Set to true if allocno can't be allocated in the stack register. */
83 extern struct allocno *allocno;
85 /* In ra-conflict.c */
87 /* Number of pseudo-registers which are candidates for allocation. */
89 extern int max_allocno;
91 /* max_allocno by max_allocno compressed triangular bit matrix,
92 recording whether two allocnos conflict (can't go in the same
93 hardware register). */
95 extern HOST_WIDEST_FAST_INT *conflicts;
97 /* Indexed by (pseudo) reg number, gives the allocno, or -1
98 for pseudo registers which are not to be allocated. */
100 extern int *reg_allocno;
102 /* Precalculated partial bit number in the compressed triangular bit matrix.
103 For two allocnos, the final bit number is: partial_bitnum[LOW] + HIGH. */
105 extern HOST_WIDE_INT *partial_bitnum;
107 /* Size in bits of the compressed triangular bit matrix. */
109 extern HOST_WIDE_INT max_bitnum;
111 /* The pool to allocate the adjacency list elements from. */
113 extern alloc_pool adjacency_pool;
115 /* The maximum number of neighbors stored in the neighbors vector before
116 we have to chain in another vector. */
118 #define ADJACENCY_VEC_LENGTH 30
120 /* Conflict graph adjacency list. */
122 typedef struct adjacency_list_d
124 int neighbors[ADJACENCY_VEC_LENGTH];
126 struct adjacency_list_d *next;
129 extern adjacency_t **adjacency;
131 /* Add NEIGHBOR to ALLOC_NO's adjacency list. It is assumed the caller
132 has already determined that NEIGHBOR is not already neighbor by
133 checking the conflict bit matrix. */
136 add_neighbor (int alloc_no, int neighbor)
138 adjacency_t *adjlist = adjacency[alloc_no];
140 if (adjlist == NULL || adjlist->index == ADJACENCY_VEC_LENGTH)
142 adjacency_t *new = pool_alloc (adjacency_pool);
146 adjacency[alloc_no] = adjlist;
149 adjlist->neighbors[adjlist->index++] = neighbor;
152 /* Iterator for adjacency lists. */
154 typedef struct adjacency_iterator_d
160 /* Initialize a single adjacency list iterator. */
163 adjacency_iter_init (adjacency_iter *ai, int allocno1)
165 ai->vec = adjacency[allocno1];
167 return ai->vec != NULL;
170 /* Test whether we have visited all of the neighbors. */
173 adjacency_iter_done (adjacency_iter *ai)
175 return ai->idx > ai->vec->index;
178 /* Advance to the next neighbor in AI. */
181 adjacency_iter_next (adjacency_iter *ai)
183 unsigned int idx = ai->idx;
184 int neighbor = ai->vec->neighbors[idx++];
185 if (idx >= ai->vec->index && ai->vec->next != NULL)
187 ai->vec = ai->vec->next;
195 /* Return the one basic block regno is used in. If regno is used
196 in more than one basic block or if it is unknown which block it
197 is used in, return 0. */
200 regno_basic_block (int regno)
202 int block = REG_BASIC_BLOCK (regno);
208 extern void global_conflicts (void);
212 /* Macro to visit all of IN_ALLOCNO's neighbors. Neighbors are
213 returned in OUT_ALLOCNO for each iteration of the loop. */
215 #define FOR_EACH_CONFLICT(IN_ALLOCNO, OUT_ALLOCNO, ITER) \
216 if (!adjacency || !adjacency_iter_init (&(ITER), (IN_ALLOCNO))) \
219 for ((OUT_ALLOCNO) = adjacency_iter_next (&(ITER)); \
220 !adjacency_iter_done (&(ITER)); \
221 (OUT_ALLOCNO) = adjacency_iter_next (&(ITER)))
223 extern void ra_init_live_subregs (bool, sbitmap *, int *, int, rtx);
224 extern bool conflict_p (int, int);
226 #endif /* GCC_RA_H */