1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990
|
/* Nested function decomposition for trees.
Copyright (C) 2004, 2005, 2006 Free Software Foundation, Inc.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GCC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to
the Free Software Foundation, 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
#include "rtl.h"
#include "tm_p.h"
#include "function.h"
#include "tree-dump.h"
#include "tree-inline.h"
#include "tree-gimple.h"
#include "tree-iterator.h"
#include "tree-flow.h"
#include "cgraph.h"
#include "expr.h"
#include "langhooks.h"
#include "ggc.h"
/* The object of this pass is to lower the representation of a set of nested
functions in order to expose all of the gory details of the various
nonlocal references. We want to do this sooner rather than later, in
order to give us more freedom in emitting all of the functions in question.
Back in olden times, when gcc was young, we developed an insanely
complicated scheme whereby variables which were referenced nonlocally
were forced to live in the stack of the declaring function, and then
the nested functions magically discovered where these variables were
placed. In order for this scheme to function properly, it required
that the outer function be partially expanded, then we switch to
compiling the inner function, and once done with those we switch back
to compiling the outer function. Such delicate ordering requirements
makes it difficult to do whole translation unit optimizations
involving such functions.
The implementation here is much more direct. Everything that can be
referenced by an inner function is a member of an explicitly created
structure herein called the "nonlocal frame struct". The incoming
static chain for a nested function is a pointer to this struct in
the parent. In this way, we settle on known offsets from a known
base, and so are decoupled from the logic that places objects in the
function's stack frame. More importantly, we don't have to wait for
that to happen -- since the compilation of the inner function is no
longer tied to a real stack frame, the nonlocal frame struct can be
allocated anywhere. Which means that the outer function is now
inlinable.
Theory of operation here is very simple. Iterate over all the
statements in all the functions (depth first) several times,
allocating structures and fields on demand. In general we want to
examine inner functions first, so that we can avoid making changes
to outer functions which are unnecessary.
The order of the passes matters a bit, in that later passes will be
skipped if it is discovered that the functions don't actually interact
at all. That is, they're nested in the lexical sense but could have
been written as independent functions without change. */
struct var_map_elt GTY(())
{
tree old;
tree new;
};
struct nesting_info GTY ((chain_next ("%h.next")))
{
struct nesting_info *outer;
struct nesting_info *inner;
struct nesting_info *next;
htab_t GTY ((param_is (struct var_map_elt))) field_map;
htab_t GTY ((param_is (struct var_map_elt))) var_map;
bitmap suppress_expansion;
tree context;
tree new_local_var_chain;
tree debug_var_chain;
tree frame_type;
tree frame_decl;
tree chain_field;
tree chain_decl;
tree nl_goto_field;
bool any_parm_remapped;
bool any_tramp_created;
char static_chain_added;
};
/* Hashing and equality functions for nesting_info->var_map. */
static hashval_t
var_map_hash (const void *x)
{
const struct var_map_elt *a = (const struct var_map_elt *) x;
return htab_hash_pointer (a->old);
}
static int
var_map_eq (const void *x, const void *y)
{
const struct var_map_elt *a = (const struct var_map_elt *) x;
const struct var_map_elt *b = (const struct var_map_elt *) y;
return a->old == b->old;
}
/* We're working in so many different function contexts simultaneously,
that create_tmp_var is dangerous. Prevent mishap. */
#define create_tmp_var cant_use_create_tmp_var_here_dummy
/* Like create_tmp_var, except record the variable for registration at
the given nesting level. */
static tree
create_tmp_var_for (struct nesting_info *info, tree type, const char *prefix)
{
tree tmp_var;
/* If the type is of variable size or a type which must be created by the
frontend, something is wrong. Note that we explicitly allow
incomplete types here, since we create them ourselves here. */
gcc_assert (!TREE_ADDRESSABLE (type));
gcc_assert (!TYPE_SIZE_UNIT (type)
|| TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST);
tmp_var = create_tmp_var_raw (type, prefix);
DECL_CONTEXT (tmp_var) = info->context;
TREE_CHAIN (tmp_var) = info->new_local_var_chain;
DECL_SEEN_IN_BIND_EXPR_P (tmp_var) = 1;
if (TREE_CODE (type) == COMPLEX_TYPE)
DECL_COMPLEX_GIMPLE_REG_P (tmp_var) = 1;
info->new_local_var_chain = tmp_var;
return tmp_var;
}
/* Take the address of EXP to be used within function CONTEXT.
Mark it for addressability as necessary. */
tree
build_addr (tree exp, tree context)
{
tree base = exp;
tree save_context;
tree retval;
while (handled_component_p (base))
base = TREE_OPERAND (base, 0);
if (DECL_P (base))
TREE_ADDRESSABLE (base) = 1;
/* Building the ADDR_EXPR will compute a set of properties for
that ADDR_EXPR. Those properties are unfortunately context
specific. ie, they are dependent on CURRENT_FUNCTION_DECL.
Temporarily set CURRENT_FUNCTION_DECL to the desired context,
build the ADDR_EXPR, then restore CURRENT_FUNCTION_DECL. That
way the properties are for the ADDR_EXPR are computed properly. */
save_context = current_function_decl;
current_function_decl = context;
retval = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
current_function_decl = save_context;;
return retval;
}
/* Insert FIELD into TYPE, sorted by alignment requirements. */
void
insert_field_into_struct (tree type, tree field)
{
tree *p;
DECL_CONTEXT (field) = type;
for (p = &TYPE_FIELDS (type); *p ; p = &TREE_CHAIN (*p))
if (DECL_ALIGN (field) >= DECL_ALIGN (*p))
break;
TREE_CHAIN (field) = *p;
*p = field;
}
/* Build or return the RECORD_TYPE that describes the frame state that is
shared between INFO->CONTEXT and its nested functions. This record will
not be complete until finalize_nesting_tree; up until that point we'll
be adding fields as necessary.
We also build the DECL that represents this frame in the function. */
static tree
get_frame_type (struct nesting_info *info)
{
tree type = info->frame_type;
if (!type)
{
char *name;
type = make_node (RECORD_TYPE);
name = concat ("FRAME.",
IDENTIFIER_POINTER (DECL_NAME (info->context)),
NULL);
TYPE_NAME (type) = get_identifier (name);
free (name);
info->frame_type = type;
info->frame_decl = create_tmp_var_for (info, type, "FRAME");
/* ??? Always make it addressable for now, since it is meant to
be pointed to by the static chain pointer. This pessimizes
when it turns out that no static chains are needed because
the nested functions referencing non-local variables are not
reachable, but the true pessimization is to create the non-
local frame structure in the first place. */
TREE_ADDRESSABLE (info->frame_decl) = 1;
}
return type;
}
/* Return true if DECL should be referenced by pointer in the non-local
frame structure. */
static bool
use_pointer_in_frame (tree decl)
{
if (TREE_CODE (decl) == PARM_DECL)
{
/* It's illegal to copy TREE_ADDRESSABLE, impossible to copy variable
sized decls, and inefficient to copy large aggregates. Don't bother
moving anything but scalar variables. */
return AGGREGATE_TYPE_P (TREE_TYPE (decl));
}
else
{
/* Variable sized types make things "interesting" in the frame. */
return DECL_SIZE (decl) == NULL || !TREE_CONSTANT (DECL_SIZE (decl));
}
}
/* Given DECL, a non-locally accessed variable, find or create a field
in the non-local frame structure for the given nesting context. */
static tree
lookup_field_for_decl (struct nesting_info *info, tree decl,
enum insert_option insert)
{
struct var_map_elt *elt, dummy;
void **slot;
tree field;
dummy.old = decl;
slot = htab_find_slot (info->field_map, &dummy, insert);
if (!slot)
{
gcc_assert (insert != INSERT);
return NULL;
}
elt = (struct var_map_elt *) *slot;
if (!elt && insert == INSERT)
{
field = make_node (FIELD_DECL);
DECL_NAME (field) = DECL_NAME (decl);
if (use_pointer_in_frame (decl))
{
TREE_TYPE (field) = build_pointer_type (TREE_TYPE (decl));
DECL_ALIGN (field) = TYPE_ALIGN (TREE_TYPE (field));
DECL_NONADDRESSABLE_P (field) = 1;
}
else
{
TREE_TYPE (field) = TREE_TYPE (decl);
DECL_SOURCE_LOCATION (field) = DECL_SOURCE_LOCATION (decl);
DECL_ALIGN (field) = DECL_ALIGN (decl);
DECL_USER_ALIGN (field) = DECL_USER_ALIGN (decl);
TREE_ADDRESSABLE (field) = TREE_ADDRESSABLE (decl);
DECL_NONADDRESSABLE_P (field) = !TREE_ADDRESSABLE (decl);
TREE_THIS_VOLATILE (field) = TREE_THIS_VOLATILE (decl);
}
insert_field_into_struct (get_frame_type (info), field);
elt = GGC_NEW (struct var_map_elt);
elt->old = decl;
elt->new = field;
*slot = elt;
if (TREE_CODE (decl) == PARM_DECL)
info->any_parm_remapped = true;
}
else
field = elt ? elt->new : NULL;
return field;
}
/* Build or return the variable that holds the static chain within
INFO->CONTEXT. This variable may only be used within INFO->CONTEXT. */
static tree
get_chain_decl (struct nesting_info *info)
{
tree decl = info->chain_decl;
if (!decl)
{
tree type;
type = get_frame_type (info->outer);
type = build_pointer_type (type);
/* Note that this variable is *not* entered into any BIND_EXPR;
the construction of this variable is handled specially in
expand_function_start and initialize_inlined_parameters.
Note also that it's represented as a parameter. This is more
close to the truth, since the initial value does come from
the caller. */
decl = build_decl (PARM_DECL, create_tmp_var_name ("CHAIN"), type);
DECL_ARTIFICIAL (decl) = 1;
DECL_IGNORED_P (decl) = 1;
TREE_USED (decl) = 1;
DECL_CONTEXT (decl) = info->context;
DECL_ARG_TYPE (decl) = type;
/* Tell tree-inline.c that we never write to this variable, so
it can copy-prop the replacement value immediately. */
TREE_READONLY (decl) = 1;
info->chain_decl = decl;
}
return decl;
}
/* Build or return the field within the non-local frame state that holds
the static chain for INFO->CONTEXT. This is the way to walk back up
multiple nesting levels. */
static tree
get_chain_field (struct nesting_info *info)
{
tree field = info->chain_field;
if (!field)
{
tree type = build_pointer_type (get_frame_type (info->outer));
field = make_node (FIELD_DECL);
DECL_NAME (field) = get_identifier ("__chain");
TREE_TYPE (field) = type;
DECL_ALIGN (field) = TYPE_ALIGN (type);
DECL_NONADDRESSABLE_P (field) = 1;
insert_field_into_struct (get_frame_type (info), field);
info->chain_field = field;
}
return field;
}
/* Copy EXP into a temporary. Allocate the temporary in the context of
INFO and insert the initialization statement before TSI. */
static tree
init_tmp_var (struct nesting_info *info, tree exp, tree_stmt_iterator *tsi)
{
tree t, stmt;
t = create_tmp_var_for (info, TREE_TYPE (exp), NULL);
stmt = build2 (MODIFY_EXPR, TREE_TYPE (t), t, exp);
SET_EXPR_LOCUS (stmt, EXPR_LOCUS (tsi_stmt (*tsi)));
tsi_link_before (tsi, stmt, TSI_SAME_STMT);
return t;
}
/* Similarly, but only do so to force EXP to satisfy is_gimple_val. */
static tree
tsi_gimplify_val (struct nesting_info *info, tree exp, tree_stmt_iterator *tsi)
{
if (is_gimple_val (exp))
return exp;
else
return init_tmp_var (info, exp, tsi);
}
/* Similarly, but copy from the temporary and insert the statement
after the iterator. */
static tree
save_tmp_var (struct nesting_info *info, tree exp,
tree_stmt_iterator *tsi)
{
tree t, stmt;
t = create_tmp_var_for (info, TREE_TYPE (exp), NULL);
stmt = build2 (MODIFY_EXPR, TREE_TYPE (t), exp, t);
SET_EXPR_LOCUS (stmt, EXPR_LOCUS (tsi_stmt (*tsi)));
tsi_link_after (tsi, stmt, TSI_SAME_STMT);
return t;
}
/* Build or return the type used to represent a nested function trampoline. */
static GTY(()) tree trampoline_type;
static tree
get_trampoline_type (void)
{
tree record, t;
unsigned align, size;
if (trampoline_type)
return trampoline_type;
align = TRAMPOLINE_ALIGNMENT;
size = TRAMPOLINE_SIZE;
/* If we won't be able to guarantee alignment simply via TYPE_ALIGN,
then allocate extra space so that we can do dynamic alignment. */
if (align > STACK_BOUNDARY)
{
size += ((align/BITS_PER_UNIT) - 1) & -(STACK_BOUNDARY/BITS_PER_UNIT);
align = STACK_BOUNDARY;
}
t = build_index_type (build_int_cst (NULL_TREE, size - 1));
t = build_array_type (char_type_node, t);
t = build_decl (FIELD_DECL, get_identifier ("__data"), t);
DECL_ALIGN (t) = align;
DECL_USER_ALIGN (t) = 1;
record = make_node (RECORD_TYPE);
TYPE_NAME (record) = get_identifier ("__builtin_trampoline");
TYPE_FIELDS (record) = t;
layout_type (record);
return record;
}
/* Given DECL, a nested function, find or create a field in the non-local
frame structure for a trampoline for this function. */
static tree
lookup_tramp_for_decl (struct nesting_info *info, tree decl,
enum insert_option insert)
{
struct var_map_elt *elt, dummy;
void **slot;
tree field;
dummy.old = decl;
slot = htab_find_slot (info->var_map, &dummy, insert);
if (!slot)
{
gcc_assert (insert != INSERT);
return NULL;
}
elt = (struct var_map_elt *) *slot;
if (!elt && insert == INSERT)
{
field = make_node (FIELD_DECL);
DECL_NAME (field) = DECL_NAME (decl);
TREE_TYPE (field) = get_trampoline_type ();
TREE_ADDRESSABLE (field) = 1;
insert_field_into_struct (get_frame_type (info), field);
elt = GGC_NEW (struct var_map_elt);
elt->old = decl;
elt->new = field;
*slot = elt;
info->any_tramp_created = true;
}
else
field = elt ? elt->new : NULL;
return field;
}
/* Build or return the field within the non-local frame state that holds
the non-local goto "jmp_buf". The buffer itself is maintained by the
rtl middle-end as dynamic stack space is allocated. */
static tree
get_nl_goto_field (struct nesting_info *info)
{
tree field = info->nl_goto_field;
if (!field)
{
unsigned size;
tree type;
/* For __builtin_nonlocal_goto, we need N words. The first is the
frame pointer, the rest is for the target's stack pointer save
area. The number of words is controlled by STACK_SAVEAREA_MODE;
not the best interface, but it'll do for now. */
if (Pmode == ptr_mode)
type = ptr_type_node;
else
type = lang_hooks.types.type_for_mode (Pmode, 1);
size = GET_MODE_SIZE (STACK_SAVEAREA_MODE (SAVE_NONLOCAL));
size = size / GET_MODE_SIZE (Pmode);
size = size + 1;
type = build_array_type
(type, build_index_type (build_int_cst (NULL_TREE, size)));
field = make_node (FIELD_DECL);
DECL_NAME (field) = get_identifier ("__nl_goto_buf");
TREE_TYPE (field) = type;
DECL_ALIGN (field) = TYPE_ALIGN (type);
TREE_ADDRESSABLE (field) = 1;
insert_field_into_struct (get_frame_type (info), field);
info->nl_goto_field = field;
}
return field;
}
/* Helper function for walk_stmts. Walk output operands of an ASM_EXPR. */
static void
walk_asm_expr (struct walk_stmt_info *wi, tree stmt)
{
int noutputs = list_length (ASM_OUTPUTS (stmt));
const char **oconstraints
= (const char **) alloca ((noutputs) * sizeof (const char *));
int i;
tree link;
const char *constraint;
bool allows_mem, allows_reg, is_inout;
wi->is_lhs = true;
for (i=0, link = ASM_OUTPUTS (stmt); link; ++i, link = TREE_CHAIN (link))
{
constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
oconstraints[i] = constraint;
parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
&allows_reg, &is_inout);
wi->val_only = (allows_reg || !allows_mem);
walk_tree (&TREE_VALUE (link), wi->callback, wi, NULL);
}
for (link = ASM_INPUTS (stmt); link; link = TREE_CHAIN (link))
{
constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
parse_input_constraint (&constraint, 0, 0, noutputs, 0,
oconstraints, &allows_mem, &allows_reg);
wi->val_only = (allows_reg || !allows_mem);
/* Although input "m" is not really a LHS, we need a lvalue. */
wi->is_lhs = !wi->val_only;
walk_tree (&TREE_VALUE (link), wi->callback, wi, NULL);
}
wi->is_lhs = false;
wi->val_only = true;
}
/* Iterate over all sub-statements of *TP calling walk_tree with
WI->CALLBACK for every sub-expression in each statement found. */
void
walk_stmts (struct walk_stmt_info *wi, tree *tp)
{
tree t = *tp;
int walk_subtrees;
if (!t)
return;
if (wi->want_locations && EXPR_HAS_LOCATION (t))
input_location = EXPR_LOCATION (t);
switch (TREE_CODE (t))
{
case STATEMENT_LIST:
{
tree_stmt_iterator i;
for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
{
wi->tsi = i;
walk_stmts (wi, tsi_stmt_ptr (i));
}
}
break;
case COND_EXPR:
walk_tree (&COND_EXPR_COND (t), wi->callback, wi, NULL);
walk_stmts (wi, &COND_EXPR_THEN (t));
walk_stmts (wi, &COND_EXPR_ELSE (t));
break;
case CATCH_EXPR:
walk_stmts (wi, &CATCH_BODY (t));
break;
case EH_FILTER_EXPR:
walk_stmts (wi, &EH_FILTER_FAILURE (t));
break;
case TRY_CATCH_EXPR:
case TRY_FINALLY_EXPR:
walk_stmts (wi, &TREE_OPERAND (t, 0));
walk_stmts (wi, &TREE_OPERAND (t, 1));
break;
case BIND_EXPR:
if (wi->want_bind_expr)
{
walk_subtrees = 1;
wi->callback (tp, &walk_subtrees, wi);
if (!walk_subtrees)
break;
}
walk_stmts (wi, &BIND_EXPR_BODY (t));
break;
case RETURN_EXPR:
if (wi->want_return_expr)
{
walk_subtrees = 1;
wi->callback (tp, &walk_subtrees, wi);
if (!walk_subtrees)
break;
}
walk_stmts (wi, &TREE_OPERAND (t, 0));
break;
case MODIFY_EXPR:
/* A formal temporary lhs may use a COMPONENT_REF rhs. */
wi->val_only = !is_gimple_formal_tmp_var (TREE_OPERAND (t, 0));
walk_tree (&TREE_OPERAND (t, 1), wi->callback, wi, NULL);
/* If the rhs is appropriate for a memory, we may use a
COMPONENT_REF on the lhs. */
wi->val_only = !is_gimple_mem_rhs (TREE_OPERAND (t, 1));
wi->is_lhs = true;
walk_tree (&TREE_OPERAND (t, 0), wi->callback, wi, NULL);
wi->val_only = true;
wi->is_lhs = false;
break;
case ASM_EXPR:
walk_asm_expr (wi, *tp);
break;
default:
wi->val_only = true;
walk_tree (tp, wi->callback, wi, NULL);
break;
}
}
/* Invoke CALLBACK on all statements of *STMT_P. */
static void
walk_body (walk_tree_fn callback, struct nesting_info *info, tree *stmt_p)
{
struct walk_stmt_info wi;
memset (&wi, 0, sizeof (wi));
wi.callback = callback;
wi.info = info;
wi.val_only = true;
walk_stmts (&wi, stmt_p);
}
/* Invoke CALLBACK on all statements of INFO->CONTEXT. */
static inline void
walk_function (walk_tree_fn callback, struct nesting_info *info)
{
walk_body (callback, info, &DECL_SAVED_TREE (info->context));
}
/* Similarly for ROOT and all functions nested underneath, depth first. */
static void
walk_all_functions (walk_tree_fn callback, struct nesting_info *root)
{
do
{
if (root->inner)
walk_all_functions (callback, root->inner);
walk_function (callback, root);
root = root->next;
}
while (root);
}
/* We have to check for a fairly pathological case. The operands of function
nested function are to be interpreted in the context of the enclosing
function. So if any are variably-sized, they will get remapped when the
enclosing function is inlined. But that remapping would also have to be
done in the types of the PARM_DECLs of the nested function, meaning the
argument types of that function will disagree with the arguments in the
calls to that function. So we'd either have to make a copy of the nested
function corresponding to each time the enclosing function was inlined or
add a VIEW_CONVERT_EXPR to each such operand for each call to the nested
function. The former is not practical. The latter would still require
detecting this case to know when to add the conversions. So, for now at
least, we don't inline such an enclosing function.
We have to do that check recursively, so here return indicating whether
FNDECL has such a nested function. ORIG_FN is the function we were
trying to inline to use for checking whether any argument is variably
modified by anything in it.
It would be better to do this in tree-inline.c so that we could give
the appropriate warning for why a function can't be inlined, but that's
too late since the nesting structure has already been flattened and
adding a flag just to record this fact seems a waste of a flag. */
static bool
check_for_nested_with_variably_modified (tree fndecl, tree orig_fndecl)
{
struct cgraph_node *cgn = cgraph_node (fndecl);
tree arg;
for (cgn = cgn->nested; cgn ; cgn = cgn->next_nested)
{
for (arg = DECL_ARGUMENTS (cgn->decl); arg; arg = TREE_CHAIN (arg))
if (variably_modified_type_p (TREE_TYPE (arg), 0), orig_fndecl)
return true;
if (check_for_nested_with_variably_modified (cgn->decl, orig_fndecl))
return true;
}
return false;
}
/* Construct our local datastructure describing the function nesting
tree rooted by CGN. */
static struct nesting_info *
create_nesting_tree (struct cgraph_node *cgn)
{
struct nesting_info *info = GGC_CNEW (struct nesting_info);
info->field_map = htab_create_ggc (7, var_map_hash, var_map_eq, ggc_free);
info->var_map = htab_create_ggc (7, var_map_hash, var_map_eq, ggc_free);
info->suppress_expansion = BITMAP_GGC_ALLOC ();
info->context = cgn->decl;
for (cgn = cgn->nested; cgn ; cgn = cgn->next_nested)
{
struct nesting_info *sub = create_nesting_tree (cgn);
sub->outer = info;
sub->next = info->inner;
info->inner = sub;
}
/* See discussion at check_for_nested_with_variably_modified for a
discussion of why this has to be here. */
if (check_for_nested_with_variably_modified (info->context, info->context))
DECL_UNINLINABLE (info->context) = true;
return info;
}
/* Return an expression computing the static chain for TARGET_CONTEXT
from INFO->CONTEXT. Insert any necessary computations before TSI. */
static tree
get_static_chain (struct nesting_info *info, tree target_context,
tree_stmt_iterator *tsi)
{
struct nesting_info *i;
tree x;
if (info->context == target_context)
{
x = build_addr (info->frame_decl, target_context);
}
else
{
x = get_chain_decl (info);
for (i = info->outer; i->context != target_context; i = i->outer)
{
tree field = get_chain_field (i);
x = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (x)), x);
x = build3 (COMPONENT_REF, TREE_TYPE (field), x, field, NULL_TREE);
x = init_tmp_var (info, x, tsi);
}
}
return x;
}
/* Return an expression referencing FIELD from TARGET_CONTEXT's non-local
frame as seen from INFO->CONTEXT. Insert any necessary computations
before TSI. */
static tree
get_frame_field (struct nesting_info *info, tree target_context,
tree field, tree_stmt_iterator *tsi)
{
struct nesting_info *i;
tree x;
if (info->context == target_context)
{
/* Make sure frame_decl gets created. */
(void) get_frame_type (info);
x = info->frame_decl;
}
else
{
x = get_chain_decl (info);
for (i = info->outer; i->context != target_context; i = i->outer)
{
tree field = get_chain_field (i);
x = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (x)), x);
x = build3 (COMPONENT_REF, TREE_TYPE (field), x, field, NULL_TREE);
x = init_tmp_var (info, x, tsi);
}
x = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (x)), x);
}
x = build3 (COMPONENT_REF, TREE_TYPE (field), x, field, NULL_TREE);
return x;
}
/* A subroutine of convert_nonlocal_reference. Create a local variable
in the nested function with DECL_VALUE_EXPR set to reference the true
variable in the parent function. This is used both for debug info
and in OpenMP lowering. */
static tree
get_nonlocal_debug_decl (struct nesting_info *info, tree decl)
{
struct var_map_elt *elt, dummy;
tree target_context;
struct nesting_info *i;
tree x, field, new_decl;
void **slot;
dummy.old = decl;
slot = htab_find_slot (info->var_map, &dummy, INSERT);
elt = *slot;
if (elt)
return elt->new;
target_context = decl_function_context (decl);
/* A copy of the code in get_frame_field, but without the temporaries. */
if (info->context == target_context)
{
/* Make sure frame_decl gets created. */
(void) get_frame_type (info);
x = info->frame_decl;
i = info;
}
else
{
x = get_chain_decl (info);
for (i = info->outer; i->context != target_context; i = i->outer)
{
field = get_chain_field (i);
x = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (x)), x);
x = build3 (COMPONENT_REF, TREE_TYPE (field), x, field, NULL_TREE);
}
x = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (x)), x);
}
field = lookup_field_for_decl (i, decl, INSERT);
x = build3 (COMPONENT_REF, TREE_TYPE (field), x, field, NULL_TREE);
if (use_pointer_in_frame (decl))
x = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (x)), x);
/* ??? We should be remapping types as well, surely. */
new_decl = build_decl (VAR_DECL, DECL_NAME (decl), TREE_TYPE (decl));
DECL_CONTEXT (new_decl) = info->context;
DECL_SOURCE_LOCATION (new_decl) = DECL_SOURCE_LOCATION (decl);
DECL_ARTIFICIAL (new_decl) = DECL_ARTIFICIAL (decl);
DECL_IGNORED_P (new_decl) = DECL_IGNORED_P (decl);
TREE_THIS_VOLATILE (new_decl) = TREE_THIS_VOLATILE (decl);
TREE_SIDE_EFFECTS (new_decl) = TREE_SIDE_EFFECTS (decl);
TREE_READONLY (new_decl) = TREE_READONLY (decl);
TREE_ADDRESSABLE (new_decl) = TREE_ADDRESSABLE (decl);
DECL_SEEN_IN_BIND_EXPR_P (new_decl) = 1;
SET_DECL_VALUE_EXPR (new_decl, x);
DECL_HAS_VALUE_EXPR_P (new_decl) = 1;
elt = ggc_alloc (sizeof (*elt));
elt->old = decl;
elt->new = new_decl;
*slot = elt;
TREE_CHAIN (new_decl) = info->debug_var_chain;
info->debug_var_chain = new_decl;
return new_decl;
}
/* Called via walk_function+walk_tree, rewrite all references to VAR
and PARM_DECLs that belong to outer functions.
The rewrite will involve some number of structure accesses back up
the static chain. E.g. for a variable FOO up one nesting level it'll
be CHAIN->FOO. For two levels it'll be CHAIN->__chain->FOO. Further
indirections apply to decls for which use_pointer_in_frame is true. */
static bool convert_nonlocal_omp_clauses (tree *, struct walk_stmt_info *);
static tree
convert_nonlocal_reference (tree *tp, int *walk_subtrees, void *data)
{
struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
struct nesting_info *info = wi->info;
tree t = *tp;
tree save_local_var_chain;
bitmap save_suppress;
*walk_subtrees = 0;
switch (TREE_CODE (t))
{
case VAR_DECL:
/* Non-automatic variables are never processed. */
if (TREE_STATIC (t) || DECL_EXTERNAL (t))
break;
/* FALLTHRU */
case PARM_DECL:
if (decl_function_context (t) != info->context)
{
tree x;
wi->changed = true;
x = get_nonlocal_debug_decl (info, t);
if (!bitmap_bit_p (info->suppress_expansion, DECL_UID (t)))
{
tree target_context = decl_function_context (t);
struct nesting_info *i;
for (i = info->outer; i->context != target_context; i = i->outer)
continue;
x = lookup_field_for_decl (i, t, INSERT);
x = get_frame_field (info, target_context, x, &wi->tsi);
if (use_pointer_in_frame (t))
{
x = init_tmp_var (info, x, &wi->tsi);
x = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (x)), x);
}
}
if (wi->val_only)
{
if (wi->is_lhs)
x = save_tmp_var (info, x, &wi->tsi);
else
x = init_tmp_var (info, x, &wi->tsi);
}
*tp = x;
}
break;
case GOTO_EXPR:
/* Don't walk non-local gotos for now. */
if (TREE_CODE (GOTO_DESTINATION (t)) != LABEL_DECL)
{
*walk_subtrees = 1;
wi->val_only = true;
wi->is_lhs = false;
}
break;
case LABEL_DECL:
/* We're taking the address of a label from a parent function, but
this is not itself a non-local goto. Mark the label such that it
will not be deleted, much as we would with a label address in
static storage. */
if (decl_function_context (t) != info->context)
FORCED_LABEL (t) = 1;
break;
case ADDR_EXPR:
{
bool save_val_only = wi->val_only;
wi->val_only = false;
wi->is_lhs = false;
wi->changed = false;
walk_tree (&TREE_OPERAND (t, 0), convert_nonlocal_reference, wi, NULL);
wi->val_only = true;
if (wi->changed)
{
tree save_context;
/* If we changed anything, then TREE_INVARIANT is be wrong,
since we're no longer directly referencing a decl. */
save_context = current_function_decl;
current_function_decl = info->context;
recompute_tree_invariant_for_addr_expr (t);
current_function_decl = save_context;
/* If the callback converted the address argument in a context
where we only accept variables (and min_invariant, presumably),
then compute the address into a temporary. */
if (save_val_only)
*tp = tsi_gimplify_val (wi->info, t, &wi->tsi);
}
}
break;
case REALPART_EXPR:
case IMAGPART_EXPR:
case COMPONENT_REF:
case ARRAY_REF:
case ARRAY_RANGE_REF:
case BIT_FIELD_REF:
/* Go down this entire nest and just look at the final prefix and
anything that describes the references. Otherwise, we lose track
of whether a NOP_EXPR or VIEW_CONVERT_EXPR needs a simple value. */
wi->val_only = true;
wi->is_lhs = false;
for (; handled_component_p (t); tp = &TREE_OPERAND (t, 0), t = *tp)
{
if (TREE_CODE (t) == COMPONENT_REF)
walk_tree (&TREE_OPERAND (t, 2), convert_nonlocal_reference, wi,
NULL);
else if (TREE_CODE (t) == ARRAY_REF
|| TREE_CODE (t) == ARRAY_RANGE_REF)
{
walk_tree (&TREE_OPERAND (t, 1), convert_nonlocal_reference, wi,
NULL);
walk_tree (&TREE_OPERAND (t, 2), convert_nonlocal_reference, wi,
NULL);
walk_tree (&TREE_OPERAND (t, 3), convert_nonlocal_reference, wi,
NULL);
}
else if (TREE_CODE (t) == BIT_FIELD_REF)
{
walk_tree (&TREE_OPERAND (t, 1), convert_nonlocal_reference, wi,
NULL);
walk_tree (&TREE_OPERAND (t, 2), convert_nonlocal_reference, wi,
NULL);
}
}
wi->val_only = false;
walk_tree (tp, convert_nonlocal_reference, wi, NULL);
break;
case OMP_PARALLEL:
save_suppress = info->suppress_expansion;
if (convert_nonlocal_omp_clauses (&OMP_PARALLEL_CLAUSES (t), wi))
{
tree c, decl;
decl = get_chain_decl (info);
c = build_omp_clause (OMP_CLAUSE_FIRSTPRIVATE);
OMP_CLAUSE_DECL (c) = decl;
OMP_CLAUSE_CHAIN (c) = OMP_PARALLEL_CLAUSES (t);
OMP_PARALLEL_CLAUSES (t) = c;
}
save_local_var_chain = info->new_local_var_chain;
info->new_local_var_chain = NULL;
walk_body (convert_nonlocal_reference, info, &OMP_PARALLEL_BODY (t));
if (info->new_local_var_chain)
declare_vars (info->new_local_var_chain, OMP_PARALLEL_BODY (t), false);
info->new_local_var_chain = save_local_var_chain;
info->suppress_expansion = save_suppress;
break;
case OMP_FOR:
case OMP_SECTIONS:
case OMP_SINGLE:
save_suppress = info->suppress_expansion;
convert_nonlocal_omp_clauses (&OMP_CLAUSES (t), wi);
walk_body (convert_nonlocal_reference, info, &OMP_BODY (t));
info->suppress_expansion = save_suppress;
break;
case OMP_SECTION:
case OMP_MASTER:
case OMP_ORDERED:
walk_body (convert_nonlocal_reference, info, &OMP_BODY (t));
break;
default:
if (!IS_TYPE_OR_DECL_P (t))
{
*walk_subtrees = 1;
wi->val_only = true;
wi->is_lhs = false;
}
break;
}
return NULL_TREE;
}
static bool
convert_nonlocal_omp_clauses (tree *pclauses, struct walk_stmt_info *wi)
{
struct nesting_info *info = wi->info;
bool need_chain = false;
tree clause, decl;
int dummy;
bitmap new_suppress;
new_suppress = BITMAP_GGC_ALLOC ();
bitmap_copy (new_suppress, info->suppress_expansion);
for (clause = *pclauses; clause ; clause = OMP_CLAUSE_CHAIN (clause))
{
switch (OMP_CLAUSE_CODE (clause))
{
case OMP_CLAUSE_PRIVATE:
case OMP_CLAUSE_FIRSTPRIVATE:
case OMP_CLAUSE_LASTPRIVATE:
case OMP_CLAUSE_REDUCTION:
case OMP_CLAUSE_COPYPRIVATE:
case OMP_CLAUSE_SHARED:
decl = OMP_CLAUSE_DECL (clause);
if (decl_function_context (decl) != info->context)
{
bitmap_set_bit (new_suppress, DECL_UID (decl));
OMP_CLAUSE_DECL (clause) = get_nonlocal_debug_decl (info, decl);
need_chain = true;
}
break;
case OMP_CLAUSE_SCHEDULE:
if (OMP_CLAUSE_SCHEDULE_CHUNK_EXPR (clause) == NULL)
break;
/* FALLTHRU */
case OMP_CLAUSE_IF:
case OMP_CLAUSE_NUM_THREADS:
wi->val_only = true;
wi->is_lhs = false;
convert_nonlocal_reference (&OMP_CLAUSE_OPERAND (clause, 0), &dummy,
wi);
break;
case OMP_CLAUSE_NOWAIT:
case OMP_CLAUSE_ORDERED:
case OMP_CLAUSE_DEFAULT:
case OMP_CLAUSE_COPYIN:
break;
default:
gcc_unreachable ();
}
}
info->suppress_expansion = new_suppress;
return need_chain;
}
/* A subroutine of convert_local_reference. Create a local variable
in the parent function with DECL_VALUE_EXPR set to reference the
field in FRAME. This is used both for debug info and in OpenMP
lowering. */
static tree
get_local_debug_decl (struct nesting_info *info, tree decl, tree field)
{
struct var_map_elt *elt, dummy;
tree x, new_decl;
void **slot;
dummy.old = decl;
slot = htab_find_slot (info->var_map, &dummy, INSERT);
elt = *slot;
if (elt)
return elt->new;
/* Make sure frame_decl gets created. */
(void) get_frame_type (info);
x = info->frame_decl;
x = build3 (COMPONENT_REF, TREE_TYPE (field), x, field, NULL_TREE);
new_decl = build_decl (VAR_DECL, DECL_NAME (decl), TREE_TYPE (decl));
DECL_CONTEXT (new_decl) = info->context;
DECL_SOURCE_LOCATION (new_decl) = DECL_SOURCE_LOCATION (decl);
DECL_ARTIFICIAL (new_decl) = DECL_ARTIFICIAL (decl);
DECL_IGNORED_P (new_decl) = DECL_IGNORED_P (decl);
TREE_THIS_VOLATILE (new_decl) = TREE_THIS_VOLATILE (decl);
TREE_SIDE_EFFECTS (new_decl) = TREE_SIDE_EFFECTS (decl);
TREE_READONLY (new_decl) = TREE_READONLY (decl);
TREE_ADDRESSABLE (new_decl) = TREE_ADDRESSABLE (decl);
DECL_SEEN_IN_BIND_EXPR_P (new_decl) = 1;
SET_DECL_VALUE_EXPR (new_decl, x);
DECL_HAS_VALUE_EXPR_P (new_decl) = 1;
elt = ggc_alloc (sizeof (*elt));
elt->old = decl;
elt->new = new_decl;
*slot = elt;
TREE_CHAIN (new_decl) = info->debug_var_chain;
info->debug_var_chain = new_decl;
/* Do not emit debug info twice. */
DECL_IGNORED_P (decl) = 1;
return new_decl;
}
/* Called via walk_function+walk_tree, rewrite all references to VAR
and PARM_DECLs that were referenced by inner nested functions.
The rewrite will be a structure reference to the local frame variable. */
static bool convert_local_omp_clauses (tree *, struct walk_stmt_info *);
static tree
convert_local_reference (tree *tp, int *walk_subtrees, void *data)
{
struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
struct nesting_info *info = wi->info;
tree t = *tp, field, x;
bool save_val_only;
tree save_local_var_chain;
bitmap save_suppress;
*walk_subtrees = 0;
switch (TREE_CODE (t))
{
case VAR_DECL:
/* Non-automatic variables are never processed. */
if (TREE_STATIC (t) || DECL_EXTERNAL (t))
break;
/* FALLTHRU */
case PARM_DECL:
if (decl_function_context (t) == info->context)
{
/* If we copied a pointer to the frame, then the original decl
is used unchanged in the parent function. */
if (use_pointer_in_frame (t))
break;
/* No need to transform anything if no child references the
variable. */
field = lookup_field_for_decl (info, t, NO_INSERT);
if (!field)
break;
wi->changed = true;
x = get_local_debug_decl (info, t, field);
if (!bitmap_bit_p (info->suppress_expansion, DECL_UID (t)))
x = get_frame_field (info, info->context, field, &wi->tsi);
if (wi->val_only)
{
if (wi->is_lhs)
x = save_tmp_var (info, x, &wi->tsi);
else
x = init_tmp_var (info, x, &wi->tsi);
}
*tp = x;
}
break;
case ADDR_EXPR:
save_val_only = wi->val_only;
wi->val_only = false;
wi->is_lhs = false;
wi->changed = false;
walk_tree (&TREE_OPERAND (t, 0), convert_local_reference, wi, NULL);
wi->val_only = save_val_only;
/* If we converted anything ... */
if (wi->changed)
{
tree save_context;
/* Then the frame decl is now addressable. */
TREE_ADDRESSABLE (info->frame_decl) = 1;
save_context = current_function_decl;
current_function_decl = info->context;
recompute_tree_invariant_for_addr_expr (t);
current_function_decl = save_context;
/* If we are in a context where we only accept values, then
compute the address into a temporary. */
if (save_val_only)
*tp = tsi_gimplify_val (wi->info, t, &wi->tsi);
}
break;
case REALPART_EXPR:
case IMAGPART_EXPR:
case COMPONENT_REF:
case ARRAY_REF:
case ARRAY_RANGE_REF:
case BIT_FIELD_REF:
/* Go down this entire nest and just look at the final prefix and
anything that describes the references. Otherwise, we lose track
of whether a NOP_EXPR or VIEW_CONVERT_EXPR needs a simple value. */
save_val_only = wi->val_only;
wi->val_only = true;
wi->is_lhs = false;
for (; handled_component_p (t); tp = &TREE_OPERAND (t, 0), t = *tp)
{
if (TREE_CODE (t) == COMPONENT_REF)
walk_tree (&TREE_OPERAND (t, 2), convert_local_reference, wi,
NULL);
else if (TREE_CODE (t) == ARRAY_REF
|| TREE_CODE (t) == ARRAY_RANGE_REF)
{
walk_tree (&TREE_OPERAND (t, 1), convert_local_reference, wi,
NULL);
walk_tree (&TREE_OPERAND (t, 2), convert_local_reference, wi,
NULL);
walk_tree (&TREE_OPERAND (t, 3), convert_local_reference, wi,
NULL);
}
else if (TREE_CODE (t) == BIT_FIELD_REF)
{
walk_tree (&TREE_OPERAND (t, 1), convert_local_reference, wi,
NULL);
walk_tree (&TREE_OPERAND (t, 2), convert_local_reference, wi,
NULL);
}
}
wi->val_only = false;
walk_tree (tp, convert_local_reference, wi, NULL);
wi->val_only = save_val_only;
break;
case OMP_PARALLEL:
save_suppress = info->suppress_expansion;
if (convert_local_omp_clauses (&OMP_PARALLEL_CLAUSES (t), wi))
{
tree c;
(void) get_frame_type (info);
c = build_omp_clause (OMP_CLAUSE_SHARED);
OMP_CLAUSE_DECL (c) = info->frame_decl;
OMP_CLAUSE_CHAIN (c) = OMP_PARALLEL_CLAUSES (t);
OMP_PARALLEL_CLAUSES (t) = c;
}
save_local_var_chain = info->new_local_var_chain;
info->new_local_var_chain = NULL;
walk_body (convert_local_reference, info, &OMP_PARALLEL_BODY (t));
if (info->new_local_var_chain)
declare_vars (info->new_local_var_chain, OMP_PARALLEL_BODY (t), false);
info->new_local_var_chain = save_local_var_chain;
info->suppress_expansion = save_suppress;
break;
case OMP_FOR:
case OMP_SECTIONS:
case OMP_SINGLE:
save_suppress = info->suppress_expansion;
convert_local_omp_clauses (&OMP_CLAUSES (t), wi);
walk_body (convert_local_reference, info, &OMP_BODY (t));
info->suppress_expansion = save_suppress;
break;
case OMP_SECTION:
case OMP_MASTER:
case OMP_ORDERED:
walk_body (convert_local_reference, info, &OMP_BODY (t));
break;
default:
if (!IS_TYPE_OR_DECL_P (t))
{
*walk_subtrees = 1;
wi->val_only = true;
wi->is_lhs = false;
}
break;
}
return NULL_TREE;
}
static bool
convert_local_omp_clauses (tree *pclauses, struct walk_stmt_info *wi)
{
struct nesting_info *info = wi->info;
bool need_frame = false;
tree clause, decl;
int dummy;
bitmap new_suppress;
new_suppress = BITMAP_GGC_ALLOC ();
bitmap_copy (new_suppress, info->suppress_expansion);
for (clause = *pclauses; clause ; clause = OMP_CLAUSE_CHAIN (clause))
{
switch (OMP_CLAUSE_CODE (clause))
{
case OMP_CLAUSE_PRIVATE:
case OMP_CLAUSE_FIRSTPRIVATE:
case OMP_CLAUSE_LASTPRIVATE:
case OMP_CLAUSE_REDUCTION:
case OMP_CLAUSE_COPYPRIVATE:
case OMP_CLAUSE_SHARED:
decl = OMP_CLAUSE_DECL (clause);
if (decl_function_context (decl) == info->context
&& !use_pointer_in_frame (decl))
{
tree field = lookup_field_for_decl (info, decl, NO_INSERT);
if (field)
{
bitmap_set_bit (new_suppress, DECL_UID (decl));
OMP_CLAUSE_DECL (clause)
= get_local_debug_decl (info, decl, field);
need_frame = true;
}
}
break;
case OMP_CLAUSE_SCHEDULE:
if (OMP_CLAUSE_SCHEDULE_CHUNK_EXPR (clause) == NULL)
break;
/* FALLTHRU */
case OMP_CLAUSE_IF:
case OMP_CLAUSE_NUM_THREADS:
wi->val_only = true;
wi->is_lhs = false;
convert_local_reference (&OMP_CLAUSE_OPERAND (clause, 0), &dummy, wi);
break;
case OMP_CLAUSE_NOWAIT:
case OMP_CLAUSE_ORDERED:
case OMP_CLAUSE_DEFAULT:
case OMP_CLAUSE_COPYIN:
break;
default:
gcc_unreachable ();
}
}
info->suppress_expansion = new_suppress;
return need_frame;
}
/* Called via walk_function+walk_tree, rewrite all GOTO_EXPRs that
reference labels from outer functions. The rewrite will be a
call to __builtin_nonlocal_goto. */
static tree
convert_nl_goto_reference (tree *tp, int *walk_subtrees, void *data)
{
struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
struct nesting_info *info = wi->info, *i;
tree t = *tp, label, new_label, target_context, x, arg, field;
struct var_map_elt *elt, dummy;
void **slot;
*walk_subtrees = 0;
if (TREE_CODE (t) != GOTO_EXPR)
return NULL_TREE;
label = GOTO_DESTINATION (t);
if (TREE_CODE (label) != LABEL_DECL)
return NULL_TREE;
target_context = decl_function_context (label);
if (target_context == info->context)
return NULL_TREE;
for (i = info->outer; target_context != i->context; i = i->outer)
continue;
/* The original user label may also be use for a normal goto, therefore
we must create a new label that will actually receive the abnormal
control transfer. This new label will be marked LABEL_NONLOCAL; this
mark will trigger proper behavior in the cfg, as well as cause the
(hairy target-specific) non-local goto receiver code to be generated
when we expand rtl. Enter this association into var_map so that we
can insert the new label into the IL during a second pass. */
dummy.old = label;
slot = htab_find_slot (i->var_map, &dummy, INSERT);
elt = (struct var_map_elt *) *slot;
if (elt == NULL)
{
new_label = create_artificial_label ();
DECL_NONLOCAL (new_label) = 1;
elt = GGC_NEW (struct var_map_elt);
elt->old = label;
elt->new = new_label;
*slot = elt;
}
else
new_label = elt->new;
/* Build: __builtin_nl_goto(new_label, &chain->nl_goto_field). */
field = get_nl_goto_field (i);
x = get_frame_field (info, target_context, field, &wi->tsi);
x = build_addr (x, target_context);
x = tsi_gimplify_val (info, x, &wi->tsi);
arg = tree_cons (NULL, x, NULL);
x = build_addr (new_label, target_context);
arg = tree_cons (NULL, x, arg);
x = implicit_built_in_decls[BUILT_IN_NONLOCAL_GOTO];
x = build_function_call_expr (x, arg);
SET_EXPR_LOCUS (x, EXPR_LOCUS (tsi_stmt (wi->tsi)));
*tsi_stmt_ptr (wi->tsi) = x;
return NULL_TREE;
}
/* Called via walk_function+walk_tree, rewrite all LABEL_EXPRs that
are referenced via nonlocal goto from a nested function. The rewrite
will involve installing a newly generated DECL_NONLOCAL label, and
(potentially) a branch around the rtl gunk that is assumed to be
attached to such a label. */
static tree
convert_nl_goto_receiver (tree *tp, int *walk_subtrees, void *data)
{
struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
struct nesting_info *info = wi->info;
tree t = *tp, label, new_label, x;
struct var_map_elt *elt, dummy;
tree_stmt_iterator tmp_tsi;
*walk_subtrees = 0;
if (TREE_CODE (t) != LABEL_EXPR)
return NULL_TREE;
label = LABEL_EXPR_LABEL (t);
dummy.old = label;
elt = (struct var_map_elt *) htab_find (info->var_map, &dummy);
if (!elt)
return NULL_TREE;
new_label = elt->new;
/* If there's any possibility that the previous statement falls through,
then we must branch around the new non-local label. */
tmp_tsi = wi->tsi;
tsi_prev (&tmp_tsi);
if (tsi_end_p (tmp_tsi) || block_may_fallthru (tsi_stmt (tmp_tsi)))
{
x = build1 (GOTO_EXPR, void_type_node, label);
tsi_link_before (&wi->tsi, x, TSI_SAME_STMT);
}
x = build1 (LABEL_EXPR, void_type_node, new_label);
tsi_link_before (&wi->tsi, x, TSI_SAME_STMT);
return NULL_TREE;
}
/* Called via walk_function+walk_tree, rewrite all references to addresses
of nested functions that require the use of trampolines. The rewrite
will involve a reference a trampoline generated for the occasion. */
static tree
convert_tramp_reference (tree *tp, int *walk_subtrees, void *data)
{
struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
struct nesting_info *info = wi->info, *i;
tree t = *tp, decl, target_context, x, arg;
*walk_subtrees = 0;
switch (TREE_CODE (t))
{
case ADDR_EXPR:
/* Build
T.1 = &CHAIN->tramp;
T.2 = __builtin_adjust_trampoline (T.1);
T.3 = (func_type)T.2;
*/
decl = TREE_OPERAND (t, 0);
if (TREE_CODE (decl) != FUNCTION_DECL)
break;
/* Only need to process nested functions. */
target_context = decl_function_context (decl);
if (!target_context)
break;
/* If the nested function doesn't use a static chain, then
it doesn't need a trampoline. */
if (DECL_NO_STATIC_CHAIN (decl))
break;
/* Lookup the immediate parent of the callee, as that's where
we need to insert the trampoline. */
for (i = info; i->context != target_context; i = i->outer)
continue;
x = lookup_tramp_for_decl (i, decl, INSERT);
/* Compute the address of the field holding the trampoline. */
x = get_frame_field (info, target_context, x, &wi->tsi);
x = build_addr (x, target_context);
x = tsi_gimplify_val (info, x, &wi->tsi);
arg = tree_cons (NULL, x, NULL);
/* Do machine-specific ugliness. Normally this will involve
computing extra alignment, but it can really be anything. */
x = implicit_built_in_decls[BUILT_IN_ADJUST_TRAMPOLINE];
x = build_function_call_expr (x, arg);
x = init_tmp_var (info, x, &wi->tsi);
/* Cast back to the proper function type. */
x = build1 (NOP_EXPR, TREE_TYPE (t), x);
x = init_tmp_var (info, x, &wi->tsi);
*tp = x;
break;
case CALL_EXPR:
/* Only walk call arguments, lest we generate trampolines for
direct calls. */
walk_tree (&TREE_OPERAND (t, 1), convert_tramp_reference, wi, NULL);
break;
default:
if (!IS_TYPE_OR_DECL_P (t))
*walk_subtrees = 1;
break;
}
return NULL_TREE;
}
/* Called via walk_function+walk_tree, rewrite all CALL_EXPRs that
reference nested functions to make sure that the static chain is
set up properly for the call. */
static tree
convert_call_expr (tree *tp, int *walk_subtrees, void *data)
{
struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
struct nesting_info *info = wi->info;
tree t = *tp, decl, target_context;
char save_static_chain_added;
int i;
*walk_subtrees = 0;
switch (TREE_CODE (t))
{
case CALL_EXPR:
decl = get_callee_fndecl (t);
if (!decl)
break;
target_context = decl_function_context (decl);
if (target_context && !DECL_NO_STATIC_CHAIN (decl))
{
TREE_OPERAND (t, 2)
= get_static_chain (info, target_context, &wi->tsi);
info->static_chain_added
|= (1 << (info->context != target_context));
}
break;
case RETURN_EXPR:
case MODIFY_EXPR:
case WITH_SIZE_EXPR:
/* Only return modify and with_size_expr may contain calls. */
*walk_subtrees = 1;
break;
case OMP_PARALLEL:
save_static_chain_added = info->static_chain_added;
info->static_chain_added = 0;
walk_body (convert_call_expr, info, &OMP_PARALLEL_BODY (t));
for (i = 0; i < 2; i++)
{
tree c, decl;
if ((info->static_chain_added & (1 << i)) == 0)
continue;
decl = i ? get_chain_decl (info) : info->frame_decl;
/* Don't add CHAIN.* or FRAME.* twice. */
for (c = OMP_PARALLEL_CLAUSES (t); c; c = OMP_CLAUSE_CHAIN (c))
if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
|| OMP_CLAUSE_CODE (c) == OMP_CLAUSE_SHARED)
&& OMP_CLAUSE_DECL (c) == decl)
break;
if (c == NULL)
{
c = build_omp_clause (OMP_CLAUSE_FIRSTPRIVATE);
OMP_CLAUSE_DECL (c) = decl;
OMP_CLAUSE_CHAIN (c) = OMP_PARALLEL_CLAUSES (t);
OMP_PARALLEL_CLAUSES (t) = c;
}
}
info->static_chain_added |= save_static_chain_added;
break;
case OMP_FOR:
case OMP_SECTIONS:
case OMP_SECTION:
case OMP_SINGLE:
case OMP_MASTER:
case OMP_ORDERED:
case OMP_CRITICAL:
walk_body (convert_call_expr, info, &OMP_BODY (t));
break;
default:
break;
}
return NULL_TREE;
}
/* Walk the nesting tree starting with ROOT, depth first. Convert all
trampolines and call expressions. On the way back up, determine if
a nested function actually uses its static chain; if not, remember that. */
static void
convert_all_function_calls (struct nesting_info *root)
{
do
{
if (root->inner)
convert_all_function_calls (root->inner);
walk_function (convert_tramp_reference, root);
walk_function (convert_call_expr, root);
/* If the function does not use a static chain, then remember that. */
if (root->outer && !root->chain_decl && !root->chain_field)
DECL_NO_STATIC_CHAIN (root->context) = 1;
else
gcc_assert (!DECL_NO_STATIC_CHAIN (root->context));
root = root->next;
}
while (root);
}
/* Do "everything else" to clean up or complete state collected by the
various walking passes -- lay out the types and decls, generate code
to initialize the frame decl, store critical expressions in the
struct function for rtl to find. */
static void
finalize_nesting_tree_1 (struct nesting_info *root)
{
tree stmt_list = NULL;
tree context = root->context;
struct function *sf;
/* If we created a non-local frame type or decl, we need to lay them
out at this time. */
if (root->frame_type)
{
/* In some cases the frame type will trigger the -Wpadded warning.
This is not helpful; suppress it. */
int save_warn_padded = warn_padded;
warn_padded = 0;
layout_type (root->frame_type);
warn_padded = save_warn_padded;
layout_decl (root->frame_decl, 0);
}
/* If any parameters were referenced non-locally, then we need to
insert a copy. Likewise, if any variables were referenced by
pointer, we need to initialize the address. */
if (root->any_parm_remapped)
{
tree p;
for (p = DECL_ARGUMENTS (context); p ; p = TREE_CHAIN (p))
{
tree field, x, y;
field = lookup_field_for_decl (root, p, NO_INSERT);
if (!field)
continue;
if (use_pointer_in_frame (p))
x = build_addr (p, context);
else
x = p;
y = build3 (COMPONENT_REF, TREE_TYPE (field),
root->frame_decl, field, NULL_TREE);
x = build2 (MODIFY_EXPR, TREE_TYPE (field), y, x);
append_to_statement_list (x, &stmt_list);
}
}
/* If a chain_field was created, then it needs to be initialized
from chain_decl. */
if (root->chain_field)
{
tree x = build3 (COMPONENT_REF, TREE_TYPE (root->chain_field),
root->frame_decl, root->chain_field, NULL_TREE);
x = build2 (MODIFY_EXPR, TREE_TYPE (x), x, get_chain_decl (root));
append_to_statement_list (x, &stmt_list);
}
/* If trampolines were created, then we need to initialize them. */
if (root->any_tramp_created)
{
struct nesting_info *i;
for (i = root->inner; i ; i = i->next)
{
tree arg, x, field;
field = lookup_tramp_for_decl (root, i->context, NO_INSERT);
if (!field)
continue;
if (DECL_NO_STATIC_CHAIN (i->context))
x = null_pointer_node;
else
x = build_addr (root->frame_decl, context);
arg = tree_cons (NULL, x, NULL);
x = build_addr (i->context, context);
arg = tree_cons (NULL, x, arg);
x = build3 (COMPONENT_REF, TREE_TYPE (field),
root->frame_decl, field, NULL_TREE);
x = build_addr (x, context);
arg = tree_cons (NULL, x, arg);
x = implicit_built_in_decls[BUILT_IN_INIT_TRAMPOLINE];
x = build_function_call_expr (x, arg);
append_to_statement_list (x, &stmt_list);
}
}
/* If we created initialization statements, insert them. */
if (stmt_list)
{
annotate_all_with_locus (&stmt_list,
DECL_SOURCE_LOCATION (context));
append_to_statement_list (BIND_EXPR_BODY (DECL_SAVED_TREE (context)),
&stmt_list);
BIND_EXPR_BODY (DECL_SAVED_TREE (context)) = stmt_list;
}
/* If a chain_decl was created, then it needs to be registered with
struct function so that it gets initialized from the static chain
register at the beginning of the function. */
sf = DECL_STRUCT_FUNCTION (root->context);
sf->static_chain_decl = root->chain_decl;
/* Similarly for the non-local goto save area. */
if (root->nl_goto_field)
{
sf->nonlocal_goto_save_area
= get_frame_field (root, context, root->nl_goto_field, NULL);
sf->has_nonlocal_label = 1;
}
/* Make sure all new local variables get inserted into the
proper BIND_EXPR. */
if (root->new_local_var_chain)
declare_vars (root->new_local_var_chain, DECL_SAVED_TREE (root->context),
false);
if (root->debug_var_chain)
declare_vars (root->debug_var_chain, DECL_SAVED_TREE (root->context),
true);
/* Dump the translated tree function. */
dump_function (TDI_nested, root->context);
}
static void
finalize_nesting_tree (struct nesting_info *root)
{
do
{
if (root->inner)
finalize_nesting_tree (root->inner);
finalize_nesting_tree_1 (root);
root = root->next;
}
while (root);
}
/* Unnest the nodes and pass them to cgraph. */
static void
unnest_nesting_tree_1 (struct nesting_info *root)
{
struct cgraph_node *node = cgraph_node (root->context);
/* For nested functions update the cgraph to reflect unnesting.
We also delay finalizing of these functions up to this point. */
if (node->origin)
{
cgraph_unnest_node (cgraph_node (root->context));
cgraph_finalize_function (root->context, true);
}
}
static void
unnest_nesting_tree (struct nesting_info *root)
{
do
{
if (root->inner)
unnest_nesting_tree (root->inner);
unnest_nesting_tree_1 (root);
root = root->next;
}
while (root);
}
/* Free the data structures allocated during this pass. */
static void
free_nesting_tree (struct nesting_info *root)
{
struct nesting_info *next;
do
{
if (root->inner)
free_nesting_tree (root->inner);
htab_delete (root->var_map);
next = root->next;
ggc_free (root);
root = next;
}
while (root);
}
static GTY(()) struct nesting_info *root;
/* Main entry point for this pass. Process FNDECL and all of its nested
subroutines and turn them into something less tightly bound. */
void
lower_nested_functions (tree fndecl)
{
struct cgraph_node *cgn;
/* If there are no nested functions, there's nothing to do. */
cgn = cgraph_node (fndecl);
if (!cgn->nested)
return;
root = create_nesting_tree (cgn);
walk_all_functions (convert_nonlocal_reference, root);
walk_all_functions (convert_local_reference, root);
walk_all_functions (convert_nl_goto_reference, root);
walk_all_functions (convert_nl_goto_receiver, root);
convert_all_function_calls (root);
finalize_nesting_tree (root);
unnest_nesting_tree (root);
free_nesting_tree (root);
root = NULL;
}
#include "gt-tree-nested.h"
|