1 /* List management for the GNU C-Compiler expander.
2 Copyright (C) 1987, 88, 92-97, 1998, 1999 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
27 /* Functions for maintaining cache-able lists of EXPR_LIST and INSN_LISTs. */
29 /* An INSN_LIST containing all INSN_LISTs allocated but currently unused. */
30 static rtx unused_insn_list;
32 /* An EXPR_LIST containing all EXPR_LISTs allocated but currently unused. */
33 static rtx unused_expr_list;
36 /* This function will free an entire list of either EXPR_LIST or INSN_LIST
37 nodes. This is to be used only only lists that consist exclusively of
38 nodes of one type only. This is only called by free_EXPR_LIST_list
39 and free_INSN_LIST_list. */
41 free_list (listp, unused_listp)
42 rtx *listp, *unused_listp;
44 register rtx link, prev_link;
47 link = XEXP (prev_link, 1);
52 link = XEXP (link, 1);
55 XEXP (prev_link, 1) = *unused_listp;
56 *unused_listp = *listp;
60 /* This call is used in place of a gen_rtx_INSN_LIST. If there is a cached
61 node available, we'll use it, otherwise a call to gen_rtx_INSN_LIST
64 alloc_INSN_LIST (val, next)
72 unused_insn_list = XEXP (r, 1);
75 PUT_REG_NOTE_KIND (r, VOIDmode);
78 r = gen_rtx_INSN_LIST (VOIDmode, val, next);
83 /* This call is used in place of a gen_rtx_EXPR_LIST. If there is a cached
84 node available, we'll use it, otherwise a call to gen_rtx_EXPR_LIST
87 alloc_EXPR_LIST (kind, val, next)
96 unused_expr_list = XEXP (r, 1);
99 PUT_REG_NOTE_KIND (r, kind);
102 r = gen_rtx_EXPR_LIST (kind, val, next);
107 /* This function will initialize the EXPR_LIST and INSN_LIST caches. */
111 void *dummy ATTRIBUTE_UNUSED;
113 unused_expr_list = NULL;
114 unused_insn_list = NULL;
118 init_EXPR_INSN_LIST_cache ()
120 static int initialized;
124 ggc_add_root (&unused_expr_list, 1, 1, zap_lists);
127 unused_expr_list = NULL;
128 unused_insn_list = NULL;
131 /* This function will free up an entire list of EXPR_LIST nodes. */
133 free_EXPR_LIST_list (listp)
138 free_list (listp, &unused_expr_list);
141 /* This function will free up an entire list of INSN_LIST nodes. */
143 free_INSN_LIST_list (listp)
148 free_list (listp, &unused_insn_list);
151 /* This function will free up an individual EXPR_LIST node. */
153 free_EXPR_LIST_node (ptr)
156 XEXP (ptr, 1) = unused_expr_list;
157 unused_expr_list = ptr;
160 /* This function will free up an individual INSN_LIST node. */
162 free_INSN_LIST_node (ptr)
165 XEXP (ptr, 1) = unused_insn_list;
166 unused_insn_list = ptr;