1 /* List management for the GCC expander. 2 Copyright (C) 1987-2013 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 "diagnostic-core.h" 25 #include "rtl.h" 26 #include "ggc.h" 27 28 static void free_list (rtx *, rtx *); 29 30 /* Functions for maintaining cache-able lists of EXPR_LIST and INSN_LISTs. */ 31 32 /* An INSN_LIST containing all INSN_LISTs allocated but currently unused. */ 33 static GTY ((deletable)) rtx unused_insn_list; 34 35 /* An EXPR_LIST containing all EXPR_LISTs allocated but currently unused. */ 36 static GTY ((deletable)) rtx unused_expr_list; 37 38 /* This function will free an entire list of either EXPR_LIST, INSN_LIST 39 or DEPS_LIST nodes. This is to be used only on lists that consist 40 exclusively of nodes of one type only. This is only called by 41 free_EXPR_LIST_list, free_INSN_LIST_list and free_DEPS_LIST_list. */ 42 static void 43 free_list (rtx *listp, rtx *unused_listp) 44 { 45 rtx link, prev_link; 46 47 prev_link = *listp; 48 link = XEXP (prev_link, 1); 49 50 gcc_assert (unused_listp != &unused_insn_list 51 || GET_CODE (prev_link) == INSN_LIST); 52 53 while (link) 54 { 55 gcc_assert (unused_listp != &unused_insn_list 56 || GET_CODE (prev_link) == INSN_LIST); 57 58 prev_link = link; 59 link = XEXP (link, 1); 60 } 61 62 XEXP (prev_link, 1) = *unused_listp; 63 *unused_listp = *listp; 64 *listp = 0; 65 } 66 67 /* Find corresponding to ELEM node in the list pointed to by LISTP. 68 This node must exist in the list. Returns pointer to that node. */ 69 static rtx * 70 find_list_elem (rtx elem, rtx *listp) 71 { 72 while (XEXP (*listp, 0) != elem) 73 listp = &XEXP (*listp, 1); 74 return listp; 75 } 76 77 /* Remove the node pointed to by LISTP from the list. */ 78 static void 79 remove_list_node (rtx *listp) 80 { 81 rtx node; 82 83 node = *listp; 84 *listp = XEXP (node, 1); 85 XEXP (node, 1) = 0; 86 } 87 88 /* Removes corresponding to ELEM node from the list pointed to by LISTP. 89 Returns that node. */ 90 rtx 91 remove_list_elem (rtx elem, rtx *listp) 92 { 93 rtx node; 94 95 listp = find_list_elem (elem, listp); 96 node = *listp; 97 remove_list_node (listp); 98 return node; 99 } 100 101 /* This call is used in place of a gen_rtx_INSN_LIST. If there is a cached 102 node available, we'll use it, otherwise a call to gen_rtx_INSN_LIST 103 is made. */ 104 rtx 105 alloc_INSN_LIST (rtx val, rtx next) 106 { 107 rtx r; 108 109 if (unused_insn_list) 110 { 111 r = unused_insn_list; 112 unused_insn_list = XEXP (r, 1); 113 XEXP (r, 0) = val; 114 XEXP (r, 1) = next; 115 PUT_REG_NOTE_KIND (r, VOIDmode); 116 117 gcc_assert (GET_CODE (r) == INSN_LIST); 118 } 119 else 120 r = gen_rtx_INSN_LIST (VOIDmode, val, next); 121 122 return r; 123 } 124 125 /* This call is used in place of a gen_rtx_EXPR_LIST. If there is a cached 126 node available, we'll use it, otherwise a call to gen_rtx_EXPR_LIST 127 is made. */ 128 rtx 129 alloc_EXPR_LIST (int kind, rtx val, rtx next) 130 { 131 rtx r; 132 133 if (unused_expr_list) 134 { 135 r = unused_expr_list; 136 unused_expr_list = XEXP (r, 1); 137 XEXP (r, 0) = val; 138 XEXP (r, 1) = next; 139 PUT_REG_NOTE_KIND (r, kind); 140 } 141 else 142 r = gen_rtx_EXPR_LIST ((enum machine_mode) kind, val, next); 143 144 return r; 145 } 146 147 /* This function will free up an entire list of EXPR_LIST nodes. */ 148 void 149 free_EXPR_LIST_list (rtx *listp) 150 { 151 if (*listp == 0) 152 return; 153 free_list (listp, &unused_expr_list); 154 } 155 156 /* This function will free up an entire list of INSN_LIST nodes. */ 157 void 158 free_INSN_LIST_list (rtx *listp) 159 { 160 if (*listp == 0) 161 return; 162 free_list (listp, &unused_insn_list); 163 } 164 165 /* Make a copy of the INSN_LIST list LINK and return it. */ 166 rtx 167 copy_INSN_LIST (rtx link) 168 { 169 rtx new_queue; 170 rtx *pqueue = &new_queue; 171 172 for (; link; link = XEXP (link, 1)) 173 { 174 rtx x = XEXP (link, 0); 175 rtx newlink = alloc_INSN_LIST (x, NULL); 176 *pqueue = newlink; 177 pqueue = &XEXP (newlink, 1); 178 } 179 *pqueue = NULL_RTX; 180 return new_queue; 181 } 182 183 /* Duplicate the INSN_LIST elements of COPY and prepend them to OLD. */ 184 rtx 185 concat_INSN_LIST (rtx copy, rtx old) 186 { 187 rtx new_rtx = old; 188 for (; copy ; copy = XEXP (copy, 1)) 189 { 190 new_rtx = alloc_INSN_LIST (XEXP (copy, 0), new_rtx); 191 PUT_REG_NOTE_KIND (new_rtx, REG_NOTE_KIND (copy)); 192 } 193 return new_rtx; 194 } 195 196 /* This function will free up an individual EXPR_LIST node. */ 197 void 198 free_EXPR_LIST_node (rtx ptr) 199 { 200 XEXP (ptr, 1) = unused_expr_list; 201 unused_expr_list = ptr; 202 } 203 204 /* This function will free up an individual INSN_LIST node. */ 205 void 206 free_INSN_LIST_node (rtx ptr) 207 { 208 gcc_assert (GET_CODE (ptr) == INSN_LIST); 209 XEXP (ptr, 1) = unused_insn_list; 210 unused_insn_list = ptr; 211 } 212 213 /* Remove and free corresponding to ELEM node in the INSN_LIST pointed to 214 by LISTP. */ 215 void 216 remove_free_INSN_LIST_elem (rtx elem, rtx *listp) 217 { 218 free_INSN_LIST_node (remove_list_elem (elem, listp)); 219 } 220 221 /* Remove and free the first node in the INSN_LIST pointed to by LISTP. */ 222 rtx 223 remove_free_INSN_LIST_node (rtx *listp) 224 { 225 rtx node = *listp; 226 rtx elem = XEXP (node, 0); 227 228 remove_list_node (listp); 229 free_INSN_LIST_node (node); 230 231 return elem; 232 } 233 234 /* Remove and free the first node in the EXPR_LIST pointed to by LISTP. */ 235 rtx 236 remove_free_EXPR_LIST_node (rtx *listp) 237 { 238 rtx node = *listp; 239 rtx elem = XEXP (node, 0); 240 241 remove_list_node (listp); 242 free_EXPR_LIST_node (node); 243 244 return elem; 245 } 246 247 #include "gt-lists.h" 248