1 /* List management for the GCC expander.
2 Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
4
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
11
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
20 02110-1301, USA. */
21
22 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tm.h"
26 #include "toplev.h"
27 #include "rtl.h"
28 #include "ggc.h"
29
30 static void free_list (rtx *, rtx *);
31 static void free_DEPS_LIST_node (rtx);
32
33 /* Functions for maintaining cache-able lists of EXPR_LIST and INSN_LISTs. */
34
35 /* An INSN_LIST containing all INSN_LISTs allocated but currently unused. */
36 static GTY ((deletable)) rtx unused_insn_list;
37
38 /* An EXPR_LIST containing all EXPR_LISTs allocated but currently unused. */
39 static GTY ((deletable)) rtx unused_expr_list;
40
41 /* An DEPS_LIST containing all DEPS_LISTs allocated but currently unused. */
42 static GTY ((deletable)) rtx unused_deps_list;
43
44
45 /* This function will free an entire list of either EXPR_LIST, INSN_LIST
46 or DEPS_LIST nodes. This is to be used only on lists that consist
47 exclusively of nodes of one type only. This is only called by
48 free_EXPR_LIST_list, free_INSN_LIST_list and free_DEPS_LIST_list. */
49 static void
free_list(rtx * listp,rtx * unused_listp)50 free_list (rtx *listp, rtx *unused_listp)
51 {
52 rtx link, prev_link;
53
54 prev_link = *listp;
55 link = XEXP (prev_link, 1);
56
57 gcc_assert ((unused_listp != &unused_insn_list
58 || GET_CODE (prev_link) == INSN_LIST)
59 && (unused_listp != &unused_deps_list
60 || GET_CODE (prev_link) == DEPS_LIST));
61
62 while (link)
63 {
64 gcc_assert ((unused_listp != &unused_insn_list
65 || GET_CODE (prev_link) == INSN_LIST)
66 && (unused_listp != &unused_deps_list
67 || GET_CODE (prev_link) == DEPS_LIST));
68
69 prev_link = link;
70 link = XEXP (link, 1);
71 }
72
73 XEXP (prev_link, 1) = *unused_listp;
74 *unused_listp = *listp;
75 *listp = 0;
76 }
77
78 /* Find corresponding to ELEM node in the list pointed to by LISTP.
79 This node must exist in the list. Returns pointer to that node. */
80 static rtx *
find_list_elem(rtx elem,rtx * listp)81 find_list_elem (rtx elem, rtx *listp)
82 {
83 while (XEXP (*listp, 0) != elem)
84 listp = &XEXP (*listp, 1);
85 return listp;
86 }
87
88 /* Remove the node pointed to by LISTP from the list. */
89 static void
remove_list_node(rtx * listp)90 remove_list_node (rtx *listp)
91 {
92 rtx node;
93
94 node = *listp;
95 *listp = XEXP (node, 1);
96 XEXP (node, 1) = 0;
97 }
98
99 /* Removes corresponding to ELEM node from the list pointed to by LISTP.
100 Returns that node. */
101 rtx
remove_list_elem(rtx elem,rtx * listp)102 remove_list_elem (rtx elem, rtx *listp)
103 {
104 rtx node;
105
106 listp = find_list_elem (elem, listp);
107 node = *listp;
108 remove_list_node (listp);
109 return node;
110 }
111
112 /* This call is used in place of a gen_rtx_INSN_LIST. If there is a cached
113 node available, we'll use it, otherwise a call to gen_rtx_INSN_LIST
114 is made. */
115 rtx
alloc_INSN_LIST(rtx val,rtx next)116 alloc_INSN_LIST (rtx val, rtx next)
117 {
118 rtx r;
119
120 if (unused_insn_list)
121 {
122 r = unused_insn_list;
123 unused_insn_list = XEXP (r, 1);
124 XEXP (r, 0) = val;
125 XEXP (r, 1) = next;
126 PUT_REG_NOTE_KIND (r, VOIDmode);
127
128 gcc_assert (GET_CODE (r) == INSN_LIST);
129 }
130 else
131 r = gen_rtx_INSN_LIST (VOIDmode, val, next);
132
133 return r;
134 }
135
136 /* This call is used in place of a gen_rtx_EXPR_LIST. If there is a cached
137 node available, we'll use it, otherwise a call to gen_rtx_EXPR_LIST
138 is made. */
139 rtx
alloc_EXPR_LIST(int kind,rtx val,rtx next)140 alloc_EXPR_LIST (int kind, rtx val, rtx next)
141 {
142 rtx r;
143
144 if (unused_expr_list)
145 {
146 r = unused_expr_list;
147 unused_expr_list = XEXP (r, 1);
148 XEXP (r, 0) = val;
149 XEXP (r, 1) = next;
150 PUT_REG_NOTE_KIND (r, kind);
151 }
152 else
153 r = gen_rtx_EXPR_LIST (kind, val, next);
154
155 return r;
156 }
157
158 /* This call is used in place of a gen_rtx_DEPS_LIST. If there is a cached
159 node available, we'll use it, otherwise a call to gen_rtx_DEPS_LIST
160 is made. */
161 rtx
alloc_DEPS_LIST(rtx val,rtx next,int ds)162 alloc_DEPS_LIST (rtx val, rtx next, int ds)
163 {
164 rtx r;
165
166 if (unused_deps_list)
167 {
168 r = unused_deps_list;
169 unused_deps_list = XEXP (r, 1);
170 XEXP (r, 0) = val;
171 XEXP (r, 1) = next;
172 XINT (r, 2) = ds;
173 PUT_REG_NOTE_KIND (r, VOIDmode);
174
175 gcc_assert (GET_CODE (r) == DEPS_LIST);
176 }
177 else
178 r = gen_rtx_DEPS_LIST (VOIDmode, val, next, ds);
179
180 return r;
181 }
182
183 /* This function will free up an entire list of EXPR_LIST nodes. */
184 void
free_EXPR_LIST_list(rtx * listp)185 free_EXPR_LIST_list (rtx *listp)
186 {
187 if (*listp == 0)
188 return;
189 free_list (listp, &unused_expr_list);
190 }
191
192 /* This function will free up an entire list of INSN_LIST nodes. */
193 void
free_INSN_LIST_list(rtx * listp)194 free_INSN_LIST_list (rtx *listp)
195 {
196 if (*listp == 0)
197 return;
198 free_list (listp, &unused_insn_list);
199 }
200
201 /* This function will free up an entire list of DEPS_LIST nodes. */
202 void
free_DEPS_LIST_list(rtx * listp)203 free_DEPS_LIST_list (rtx *listp)
204 {
205 if (*listp == 0)
206 return;
207 free_list (listp, &unused_deps_list);
208 }
209
210 /* This function will free up an individual EXPR_LIST node. */
211 void
free_EXPR_LIST_node(rtx ptr)212 free_EXPR_LIST_node (rtx ptr)
213 {
214 XEXP (ptr, 1) = unused_expr_list;
215 unused_expr_list = ptr;
216 }
217
218 /* This function will free up an individual INSN_LIST node. */
219 void
free_INSN_LIST_node(rtx ptr)220 free_INSN_LIST_node (rtx ptr)
221 {
222 gcc_assert (GET_CODE (ptr) == INSN_LIST);
223 XEXP (ptr, 1) = unused_insn_list;
224 unused_insn_list = ptr;
225 }
226
227 /* This function will free up an individual DEPS_LIST node. */
228 static void
free_DEPS_LIST_node(rtx ptr)229 free_DEPS_LIST_node (rtx ptr)
230 {
231 gcc_assert (GET_CODE (ptr) == DEPS_LIST);
232 XEXP (ptr, 1) = unused_deps_list;
233 unused_deps_list = ptr;
234 }
235
236 /* Remove and free corresponding to ELEM node in the DEPS_LIST pointed to
237 by LISTP. */
238 void
remove_free_DEPS_LIST_elem(rtx elem,rtx * listp)239 remove_free_DEPS_LIST_elem (rtx elem, rtx *listp)
240 {
241 free_DEPS_LIST_node (remove_list_elem (elem, listp));
242 }
243
244 /* Remove and free corresponding to ELEM node in the INSN_LIST pointed to
245 by LISTP. */
246 void
remove_free_INSN_LIST_elem(rtx elem,rtx * listp)247 remove_free_INSN_LIST_elem (rtx elem, rtx *listp)
248 {
249 free_INSN_LIST_node (remove_list_elem (elem, listp));
250 }
251
252 /* Create and return a copy of the DEPS_LIST LIST. */
253 rtx
copy_DEPS_LIST_list(rtx list)254 copy_DEPS_LIST_list (rtx list)
255 {
256 rtx res = NULL_RTX, *resp = &res;
257
258 while (list)
259 {
260 *resp = alloc_DEPS_LIST (XEXP (list, 0), 0, XINT (list, 2));
261 PUT_REG_NOTE_KIND (*resp, REG_NOTE_KIND (list));
262 resp = &XEXP (*resp, 1);
263 list = XEXP (list, 1);
264 }
265 return res;
266 }
267
268 #include "gt-lists.h"
269