1 | /* List management for the GCC expander. |
2 | Copyright (C) 1987-2023 Free Software Foundation, Inc. |
3 | |
4 | This file is part of GCC. |
5 | |
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 |
9 | version. |
10 | |
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 |
14 | for more details. |
15 | |
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/>. */ |
19 | |
20 | #include "config.h" |
21 | #include "system.h" |
22 | #include "coretypes.h" |
23 | #include "tm.h" |
24 | #include "rtl.h" |
25 | |
26 | static void free_list (rtx *, rtx *); |
27 | |
28 | /* Functions for maintaining cache-able lists of EXPR_LIST and INSN_LISTs. */ |
29 | |
30 | /* An INSN_LIST containing all INSN_LISTs allocated but currently unused. */ |
31 | static GTY ((deletable)) rtx unused_insn_list; |
32 | |
33 | /* An EXPR_LIST containing all EXPR_LISTs allocated but currently unused. */ |
34 | static GTY ((deletable)) rtx unused_expr_list; |
35 | |
36 | /* This function will free an entire list of either EXPR_LIST, INSN_LIST |
37 | or DEPS_LIST nodes. This is to be used only on lists that consist |
38 | exclusively of nodes of one type only. This is only called by |
39 | free_EXPR_LIST_list, free_INSN_LIST_list and free_DEPS_LIST_list. */ |
40 | static void |
41 | free_list (rtx *listp, rtx *unused_listp) |
42 | { |
43 | rtx link, prev_link; |
44 | |
45 | prev_link = *listp; |
46 | link = XEXP (prev_link, 1); |
47 | |
48 | gcc_assert (unused_listp != &unused_insn_list |
49 | || GET_CODE (prev_link) == INSN_LIST); |
50 | |
51 | while (link) |
52 | { |
53 | gcc_assert (unused_listp != &unused_insn_list |
54 | || GET_CODE (prev_link) == INSN_LIST); |
55 | |
56 | prev_link = link; |
57 | link = XEXP (link, 1); |
58 | } |
59 | |
60 | XEXP (prev_link, 1) = *unused_listp; |
61 | *unused_listp = *listp; |
62 | *listp = 0; |
63 | } |
64 | |
65 | /* Find corresponding to ELEM node in the list pointed to by LISTP. |
66 | This node must exist in the list. Returns pointer to that node. */ |
67 | static rtx * |
68 | find_list_elem (rtx elem, rtx *listp) |
69 | { |
70 | while (XEXP (*listp, 0) != elem) |
71 | listp = &XEXP (*listp, 1); |
72 | return listp; |
73 | } |
74 | |
75 | /* Remove the node pointed to by LISTP from the list. */ |
76 | static void |
77 | remove_list_node (rtx *listp) |
78 | { |
79 | rtx node; |
80 | |
81 | node = *listp; |
82 | *listp = XEXP (node, 1); |
83 | XEXP (node, 1) = 0; |
84 | } |
85 | |
86 | /* Removes corresponding to ELEM node from the list pointed to by LISTP. |
87 | Returns that node. */ |
88 | rtx |
89 | remove_list_elem (rtx elem, rtx *listp) |
90 | { |
91 | rtx node; |
92 | |
93 | listp = find_list_elem (elem, listp); |
94 | node = *listp; |
95 | remove_list_node (listp); |
96 | return node; |
97 | } |
98 | |
99 | /* This call is used in place of a gen_rtx_INSN_LIST. If there is a cached |
100 | node available, we'll use it, otherwise a call to gen_rtx_INSN_LIST |
101 | is made. */ |
102 | rtx_insn_list * |
103 | alloc_INSN_LIST (rtx val, rtx next) |
104 | { |
105 | rtx_insn_list *r; |
106 | |
107 | if (unused_insn_list) |
108 | { |
109 | r = as_a <rtx_insn_list *> (p: unused_insn_list); |
110 | unused_insn_list = r->next (); |
111 | XEXP (r, 0) = val; |
112 | XEXP (r, 1) = next; |
113 | PUT_REG_NOTE_KIND (r, VOIDmode); |
114 | |
115 | gcc_assert (GET_CODE (r) == INSN_LIST); |
116 | } |
117 | else |
118 | r = gen_rtx_INSN_LIST (VOIDmode, val, next); |
119 | |
120 | return r; |
121 | } |
122 | |
123 | /* This call is used in place of a gen_rtx_EXPR_LIST. If there is a cached |
124 | node available, we'll use it, otherwise a call to gen_rtx_EXPR_LIST |
125 | is made. */ |
126 | rtx_expr_list * |
127 | alloc_EXPR_LIST (int kind, rtx val, rtx next) |
128 | { |
129 | rtx_expr_list *r; |
130 | |
131 | if (unused_expr_list) |
132 | { |
133 | r = as_a <rtx_expr_list *> (p: unused_expr_list); |
134 | unused_expr_list = XEXP (r, 1); |
135 | XEXP (r, 0) = val; |
136 | XEXP (r, 1) = next; |
137 | PUT_REG_NOTE_KIND (r, kind); |
138 | } |
139 | else |
140 | r = gen_rtx_EXPR_LIST ((machine_mode) kind, val, next); |
141 | |
142 | return r; |
143 | } |
144 | |
145 | /* This function will free up an entire list of EXPR_LIST nodes. */ |
146 | void |
147 | free_EXPR_LIST_list (rtx_expr_list **listp) |
148 | { |
149 | if (*listp == 0) |
150 | return; |
151 | free_list (listp: (rtx *)listp, unused_listp: &unused_expr_list); |
152 | } |
153 | |
154 | /* This function will free up an entire list of INSN_LIST nodes. */ |
155 | void |
156 | free_INSN_LIST_list (rtx_insn_list **listp) |
157 | { |
158 | if (*listp == 0) |
159 | return; |
160 | free_list (listp: (rtx *)listp, unused_listp: &unused_insn_list); |
161 | } |
162 | |
163 | /* Make a copy of the INSN_LIST list LINK and return it. */ |
164 | rtx_insn_list * |
165 | copy_INSN_LIST (rtx_insn_list *link) |
166 | { |
167 | rtx_insn_list *new_queue; |
168 | rtx_insn_list **pqueue = &new_queue; |
169 | |
170 | for (; link; link = link->next ()) |
171 | { |
172 | rtx_insn *x = link->insn (); |
173 | rtx_insn_list *newlink = alloc_INSN_LIST (val: x, NULL); |
174 | *pqueue = newlink; |
175 | pqueue = (rtx_insn_list **)&XEXP (newlink, 1); |
176 | } |
177 | *pqueue = NULL; |
178 | return new_queue; |
179 | } |
180 | |
181 | /* Duplicate the INSN_LIST elements of COPY and prepend them to OLD. */ |
182 | rtx_insn_list * |
183 | concat_INSN_LIST (rtx_insn_list *copy, rtx_insn_list *old) |
184 | { |
185 | rtx_insn_list *new_rtx = old; |
186 | for (; copy ; copy = copy->next ()) |
187 | { |
188 | new_rtx = alloc_INSN_LIST (val: copy->insn (), next: new_rtx); |
189 | PUT_REG_NOTE_KIND (new_rtx, REG_NOTE_KIND (copy)); |
190 | } |
191 | return new_rtx; |
192 | } |
193 | |
194 | /* This function will free up an individual EXPR_LIST node. */ |
195 | void |
196 | free_EXPR_LIST_node (rtx ptr) |
197 | { |
198 | XEXP (ptr, 1) = unused_expr_list; |
199 | unused_expr_list = ptr; |
200 | } |
201 | |
202 | /* This function will free up an individual INSN_LIST node. */ |
203 | void |
204 | free_INSN_LIST_node (rtx ptr) |
205 | { |
206 | gcc_assert (GET_CODE (ptr) == INSN_LIST); |
207 | XEXP (ptr, 1) = unused_insn_list; |
208 | unused_insn_list = ptr; |
209 | } |
210 | |
211 | /* Remove and free corresponding to ELEM node in the INSN_LIST pointed to |
212 | by LISTP. */ |
213 | void |
214 | remove_free_INSN_LIST_elem (rtx_insn *elem, rtx_insn_list **listp) |
215 | { |
216 | free_INSN_LIST_node (ptr: remove_list_elem (elem, listp: (rtx *)listp)); |
217 | } |
218 | |
219 | /* Remove and free the first node in the INSN_LIST pointed to by LISTP. */ |
220 | rtx_insn * |
221 | remove_free_INSN_LIST_node (rtx_insn_list **listp) |
222 | { |
223 | rtx_insn_list *node = *listp; |
224 | rtx_insn *elem = node->insn (); |
225 | |
226 | remove_list_node (listp: (rtx *)listp); |
227 | free_INSN_LIST_node (ptr: node); |
228 | |
229 | return elem; |
230 | } |
231 | |
232 | /* Remove and free the first node in the EXPR_LIST pointed to by LISTP. */ |
233 | rtx |
234 | remove_free_EXPR_LIST_node (rtx_expr_list **listp) |
235 | { |
236 | rtx_expr_list *node = *listp; |
237 | rtx elem = XEXP (node, 0); |
238 | |
239 | remove_list_node (listp: (rtx *)listp); |
240 | free_EXPR_LIST_node (ptr: node); |
241 | |
242 | return elem; |
243 | } |
244 | |
245 | #include "gt-lists.h" |
246 | |