From 1590d0d42640d48e23346b9baed714d2197035ae Mon Sep 17 00:00:00 2001 From: Kazu Hirata Date: Fri, 28 Jan 2005 15:45:11 +0000 Subject: cse.c (cse_reg_info_free_list, [...]): Remove. * cse.c (cse_reg_info_free_list, cse_reg_info_used_list, cse_reg_info_used_list_end): Remove. (cse_reg_info_list, cse_reg_info_list_free): New. (get_cse_reg_info): When allocating an instance of cse_reg_info, add it to the beginning of the cse_reg_info_list list. Remove code to maintain cse_reg_info_used_list. (new_basic_block): Reset the free list to the beginning of cse_reg_info_list. From-SVN: r94375 --- gcc/cse.c | 49 +++++++++++++++++++++++++++++-------------------- 1 file changed, 29 insertions(+), 20 deletions(-) (limited to 'gcc/cse.c') diff --git a/gcc/cse.c b/gcc/cse.c index 54d184aa295..4bc201424da 100644 --- a/gcc/cse.c +++ b/gcc/cse.c @@ -329,12 +329,25 @@ struct cse_reg_info unsigned int subreg_ticked; }; -/* A free list of cse_reg_info entries. */ -static struct cse_reg_info *cse_reg_info_free_list; - -/* A used list of cse_reg_info entries. */ -static struct cse_reg_info *cse_reg_info_used_list; -static struct cse_reg_info *cse_reg_info_used_list_end; +/* We maintain a linked list of cse_reg_info instances, which is + partitioned into two pieces. The first part, pointed to by + cse_reg_info_list, is a list of those entries that are in use. The + second part, pointed to by cse_reg_info_list_free, is a list of + those entries that are not in use. + + We combine these two parts into one linked list for efficiency. + Specifically, when we take an element from the second part and want + to move it to the first part, all we have to do is move the pointer + cse_reg_info_list_free to the next element. Also, if we wish to + move all elements into the second part, we just have to move the + pointer to the first element of the list. */ + +/* A linked list of cse_reg_info entries that have been allocated so + far. */ +static struct cse_reg_info *cse_reg_info_list; + +/* A pointer to the first unused entry in the above linked list. */ +static struct cse_reg_info *cse_reg_info_list_free; /* A mapping from registers to cse_reg_info data structures. */ #define REGHASH_SHIFT 7 @@ -871,13 +884,17 @@ get_cse_reg_info (unsigned int regno) if (p == NULL) { /* Get a new cse_reg_info structure. */ - if (cse_reg_info_free_list) + if (cse_reg_info_list_free) { - p = cse_reg_info_free_list; - cse_reg_info_free_list = p->next; + p = cse_reg_info_list_free; + cse_reg_info_list_free = p->next; } else - p = xmalloc (sizeof (struct cse_reg_info)); + { + p = xmalloc (sizeof (struct cse_reg_info)); + p->next = cse_reg_info_list; + cse_reg_info_list = p; + } /* Insert into hash table. */ p->hash_next = *hash_head; @@ -889,10 +906,6 @@ get_cse_reg_info (unsigned int regno) p->subreg_ticked = -1; p->reg_qty = -regno - 1; p->regno = regno; - p->next = cse_reg_info_used_list; - cse_reg_info_used_list = p; - if (!cse_reg_info_used_list_end) - cse_reg_info_used_list_end = p; } /* Cache this lookup; we tend to be looking up information about the @@ -917,12 +930,8 @@ new_basic_block (void) memset (reg_hash, 0, sizeof reg_hash); - if (cse_reg_info_used_list) - { - cse_reg_info_used_list_end->next = cse_reg_info_free_list; - cse_reg_info_free_list = cse_reg_info_used_list; - cse_reg_info_used_list = cse_reg_info_used_list_end = 0; - } + cse_reg_info_list_free = cse_reg_info_list; + cached_cse_reg_info = 0; CLEAR_HARD_REG_SET (hard_regs_in_table); -- cgit v1.2.1