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c913f08a | 1 | /* High-level loop manipulation functions. |
8d9254fc | 2 | Copyright (C) 2004-2020 Free Software Foundation, Inc. |
b8698a0f | 3 | |
c913f08a | 4 | This file is part of GCC. |
b8698a0f | 5 | |
c913f08a ZD |
6 | GCC is free software; you can redistribute it and/or modify it |
7 | under the terms of the GNU General Public License as published by the | |
9dcd6f09 | 8 | Free Software Foundation; either version 3, or (at your option) any |
c913f08a | 9 | later version. |
b8698a0f | 10 | |
c913f08a ZD |
11 | GCC is distributed in the hope that it will be useful, but WITHOUT |
12 | ANY 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. | |
b8698a0f | 15 | |
c913f08a | 16 | You should have received a copy of the GNU General Public License |
9dcd6f09 NC |
17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
c913f08a ZD |
19 | |
20 | #include "config.h" | |
21 | #include "system.h" | |
22 | #include "coretypes.h" | |
c7131fb2 | 23 | #include "backend.h" |
c913f08a | 24 | #include "tree.h" |
c7131fb2 | 25 | #include "gimple.h" |
957060b5 AM |
26 | #include "cfghooks.h" |
27 | #include "tree-pass.h" /* ??? for TODO_update_ssa but this isn't a pass. */ | |
c7131fb2 | 28 | #include "ssa.h" |
957060b5 | 29 | #include "gimple-pretty-print.h" |
40e23961 | 30 | #include "fold-const.h" |
60393bbc | 31 | #include "cfganal.h" |
45b0be94 | 32 | #include "gimplify.h" |
5be5c238 | 33 | #include "gimple-iterator.h" |
18f429e2 | 34 | #include "gimplify-me.h" |
442b4905 | 35 | #include "tree-cfg.h" |
e28030cf AM |
36 | #include "tree-ssa-loop-ivopts.h" |
37 | #include "tree-ssa-loop-manip.h" | |
38 | #include "tree-ssa-loop-niter.h" | |
442b4905 AM |
39 | #include "tree-ssa-loop.h" |
40 | #include "tree-into-ssa.h" | |
7a300452 | 41 | #include "tree-ssa.h" |
c913f08a | 42 | #include "cfgloop.h" |
c913f08a | 43 | #include "tree-scalar-evolution.h" |
7f9bc51b | 44 | #include "tree-inline.h" |
c913f08a | 45 | |
c302207e SB |
46 | /* All bitmaps for rewriting into loop-closed SSA go on this obstack, |
47 | so that we can free them all at once. */ | |
48 | static bitmap_obstack loop_renamer_obstack; | |
49 | ||
82b85a85 ZD |
50 | /* Creates an induction variable with value BASE + STEP * iteration in LOOP. |
51 | It is expected that neither BASE nor STEP are shared with other expressions | |
52 | (unless the sharing rules allow this). Use VAR as a base var_decl for it | |
53 | (if NULL, a new temporary will be created). The increment will occur at | |
b8698a0f | 54 | INCR_POS (after it if AFTER is true, before it otherwise). INCR_POS and |
92d2b330 | 55 | AFTER can be computed using standard_iv_increment_position. The ssa versions |
82b85a85 ZD |
56 | of the variable before and after increment will be stored in VAR_BEFORE and |
57 | VAR_AFTER (unless they are NULL). */ | |
58 | ||
59 | void | |
99b1c316 | 60 | create_iv (tree base, tree step, tree var, class loop *loop, |
726a989a | 61 | gimple_stmt_iterator *incr_pos, bool after, |
82b85a85 ZD |
62 | tree *var_before, tree *var_after) |
63 | { | |
538dd0b7 DM |
64 | gassign *stmt; |
65 | gphi *phi; | |
726a989a RB |
66 | tree initial, step1; |
67 | gimple_seq stmts; | |
82b85a85 ZD |
68 | tree vb, va; |
69 | enum tree_code incr_op = PLUS_EXPR; | |
9be872b7 | 70 | edge pe = loop_preheader_edge (loop); |
82b85a85 | 71 | |
83d5977e RG |
72 | if (var != NULL_TREE) |
73 | { | |
b731b390 JJ |
74 | vb = make_ssa_name (var); |
75 | va = make_ssa_name (var); | |
83d5977e RG |
76 | } |
77 | else | |
78 | { | |
79 | vb = make_temp_ssa_name (TREE_TYPE (base), NULL, "ivtmp"); | |
80 | va = make_temp_ssa_name (TREE_TYPE (base), NULL, "ivtmp"); | |
81 | } | |
82b85a85 ZD |
82 | if (var_before) |
83 | *var_before = vb; | |
82b85a85 ZD |
84 | if (var_after) |
85 | *var_after = va; | |
86 | ||
87 | /* For easier readability of the created code, produce MINUS_EXPRs | |
88 | when suitable. */ | |
89 | if (TREE_CODE (step) == INTEGER_CST) | |
90 | { | |
91 | if (TYPE_UNSIGNED (TREE_TYPE (step))) | |
92 | { | |
987b67bc | 93 | step1 = fold_build1 (NEGATE_EXPR, TREE_TYPE (step), step); |
82b85a85 ZD |
94 | if (tree_int_cst_lt (step1, step)) |
95 | { | |
96 | incr_op = MINUS_EXPR; | |
97 | step = step1; | |
98 | } | |
99 | } | |
100 | else | |
101 | { | |
6ac01510 ILT |
102 | bool ovf; |
103 | ||
104 | if (!tree_expr_nonnegative_warnv_p (step, &ovf) | |
82b85a85 ZD |
105 | && may_negate_without_overflow_p (step)) |
106 | { | |
107 | incr_op = MINUS_EXPR; | |
987b67bc | 108 | step = fold_build1 (NEGATE_EXPR, TREE_TYPE (step), step); |
82b85a85 ZD |
109 | } |
110 | } | |
111 | } | |
5be014d5 AP |
112 | if (POINTER_TYPE_P (TREE_TYPE (base))) |
113 | { | |
628c189e RG |
114 | if (TREE_CODE (base) == ADDR_EXPR) |
115 | mark_addressable (TREE_OPERAND (base, 0)); | |
0d82a1c8 | 116 | step = convert_to_ptrofftype (step); |
5be014d5 | 117 | if (incr_op == MINUS_EXPR) |
0d82a1c8 | 118 | step = fold_build1 (NEGATE_EXPR, TREE_TYPE (step), step); |
5be014d5 AP |
119 | incr_op = POINTER_PLUS_EXPR; |
120 | } | |
9be872b7 ZD |
121 | /* Gimplify the step if necessary. We put the computations in front of the |
122 | loop (i.e. the step should be loop invariant). */ | |
1ffe34d9 | 123 | step = force_gimple_operand (step, &stmts, true, NULL_TREE); |
9be872b7 | 124 | if (stmts) |
726a989a | 125 | gsi_insert_seq_on_edge_immediate (pe, stmts); |
9be872b7 | 126 | |
0d0e4a03 | 127 | stmt = gimple_build_assign (va, incr_op, vb, step); |
ffdc40a9 EB |
128 | /* Prevent the increment from inheriting a bogus location if it is not put |
129 | immediately after a statement whose location is known. */ | |
82b85a85 | 130 | if (after) |
ffdc40a9 | 131 | { |
565ab7ef JJ |
132 | if (gsi_end_p (*incr_pos) |
133 | || (is_gimple_debug (gsi_stmt (*incr_pos)) | |
134 | && gsi_bb (*incr_pos) | |
135 | && gsi_end_p (gsi_last_nondebug_bb (gsi_bb (*incr_pos))))) | |
ffdc40a9 EB |
136 | { |
137 | edge e = single_succ_edge (gsi_bb (*incr_pos)); | |
138 | gimple_set_location (stmt, e->goto_locus); | |
139 | } | |
140 | gsi_insert_after (incr_pos, stmt, GSI_NEW_STMT); | |
141 | } | |
82b85a85 | 142 | else |
ffdc40a9 | 143 | { |
565ab7ef JJ |
144 | gimple_stmt_iterator gsi = *incr_pos; |
145 | if (!gsi_end_p (gsi) && is_gimple_debug (gsi_stmt (gsi))) | |
146 | gsi_next_nondebug (&gsi); | |
147 | if (!gsi_end_p (gsi)) | |
148 | gimple_set_location (stmt, gimple_location (gsi_stmt (gsi))); | |
ffdc40a9 EB |
149 | gsi_insert_before (incr_pos, stmt, GSI_NEW_STMT); |
150 | } | |
82b85a85 | 151 | |
8b11a64c ZD |
152 | initial = force_gimple_operand (base, &stmts, true, var); |
153 | if (stmts) | |
726a989a | 154 | gsi_insert_seq_on_edge_immediate (pe, stmts); |
82b85a85 | 155 | |
538dd0b7 DM |
156 | phi = create_phi_node (vb, loop->header); |
157 | add_phi_arg (phi, initial, loop_preheader_edge (loop), UNKNOWN_LOCATION); | |
158 | add_phi_arg (phi, va, loop_latch_edge (loop), UNKNOWN_LOCATION); | |
82b85a85 ZD |
159 | } |
160 | ||
3f9b14ff | 161 | /* Return the innermost superloop LOOP of USE_LOOP that is a superloop of |
01273677 SB |
162 | both DEF_LOOP and USE_LOOP. */ |
163 | ||
99b1c316 MS |
164 | static inline class loop * |
165 | find_sibling_superloop (class loop *use_loop, class loop *def_loop) | |
01273677 SB |
166 | { |
167 | unsigned ud = loop_depth (use_loop); | |
168 | unsigned dd = loop_depth (def_loop); | |
169 | gcc_assert (ud > 0 && dd > 0); | |
170 | if (ud > dd) | |
171 | use_loop = superloop_at_depth (use_loop, dd); | |
172 | if (ud < dd) | |
173 | def_loop = superloop_at_depth (def_loop, ud); | |
174 | while (loop_outer (use_loop) != loop_outer (def_loop)) | |
175 | { | |
176 | use_loop = loop_outer (use_loop); | |
177 | def_loop = loop_outer (def_loop); | |
178 | gcc_assert (use_loop && def_loop); | |
179 | } | |
180 | return use_loop; | |
181 | } | |
182 | ||
183 | /* DEF_BB is a basic block containing a DEF that needs rewriting into | |
184 | loop-closed SSA form. USE_BLOCKS is the set of basic blocks containing | |
185 | uses of DEF that "escape" from the loop containing DEF_BB (i.e. blocks in | |
186 | USE_BLOCKS are dominated by DEF_BB but not in the loop father of DEF_B). | |
187 | ALL_EXITS[I] is the set of all basic blocks that exit loop I. | |
188 | ||
189 | Compute the subset of LOOP_EXITS that exit the loop containing DEF_BB | |
190 | or one of its loop fathers, in which DEF is live. This set is returned | |
191 | in the bitmap LIVE_EXITS. | |
192 | ||
193 | Instead of computing the complete livein set of the def, we use the loop | |
194 | nesting tree as a form of poor man's structure analysis. This greatly | |
195 | speeds up the analysis, which is important because this function may be | |
196 | called on all SSA names that need rewriting, one at a time. */ | |
c913f08a ZD |
197 | |
198 | static void | |
01273677 SB |
199 | compute_live_loop_exits (bitmap live_exits, bitmap use_blocks, |
200 | bitmap *loop_exits, basic_block def_bb) | |
c913f08a | 201 | { |
01273677 SB |
202 | unsigned i; |
203 | bitmap_iterator bi; | |
99b1c316 | 204 | class loop *def_loop = def_bb->loop_father; |
01273677 SB |
205 | unsigned def_loop_depth = loop_depth (def_loop); |
206 | bitmap def_loop_exits; | |
207 | ||
208 | /* Normally the work list size is bounded by the number of basic | |
209 | blocks in the largest loop. We don't know this number, but we | |
210 | can be fairly sure that it will be relatively small. */ | |
ef062b13 | 211 | auto_vec<basic_block> worklist (MAX (8, n_basic_blocks_for_fn (cfun) / 128)); |
01273677 SB |
212 | |
213 | EXECUTE_IF_SET_IN_BITMAP (use_blocks, 0, i, bi) | |
214 | { | |
06e28de2 | 215 | basic_block use_bb = BASIC_BLOCK_FOR_FN (cfun, i); |
99b1c316 | 216 | class loop *use_loop = use_bb->loop_father; |
01273677 SB |
217 | gcc_checking_assert (def_loop != use_loop |
218 | && ! flow_loop_nested_p (def_loop, use_loop)); | |
219 | if (! flow_loop_nested_p (use_loop, def_loop)) | |
220 | use_bb = find_sibling_superloop (use_loop, def_loop)->header; | |
221 | if (bitmap_set_bit (live_exits, use_bb->index)) | |
9771b263 | 222 | worklist.safe_push (use_bb); |
01273677 SB |
223 | } |
224 | ||
225 | /* Iterate until the worklist is empty. */ | |
9771b263 | 226 | while (! worklist.is_empty ()) |
01273677 SB |
227 | { |
228 | edge e; | |
229 | edge_iterator ei; | |
230 | ||
231 | /* Pull a block off the worklist. */ | |
9771b263 | 232 | basic_block bb = worklist.pop (); |
01273677 SB |
233 | |
234 | /* Make sure we have at least enough room in the work list | |
235 | for all predecessors of this block. */ | |
9771b263 | 236 | worklist.reserve (EDGE_COUNT (bb->preds)); |
01273677 SB |
237 | |
238 | /* For each predecessor block. */ | |
239 | FOR_EACH_EDGE (e, ei, bb->preds) | |
240 | { | |
241 | basic_block pred = e->src; | |
99b1c316 | 242 | class loop *pred_loop = pred->loop_father; |
01273677 SB |
243 | unsigned pred_loop_depth = loop_depth (pred_loop); |
244 | bool pred_visited; | |
245 | ||
246 | /* We should have met DEF_BB along the way. */ | |
fefa31b5 | 247 | gcc_assert (pred != ENTRY_BLOCK_PTR_FOR_FN (cfun)); |
01273677 SB |
248 | |
249 | if (pred_loop_depth >= def_loop_depth) | |
250 | { | |
251 | if (pred_loop_depth > def_loop_depth) | |
252 | pred_loop = superloop_at_depth (pred_loop, def_loop_depth); | |
253 | /* If we've reached DEF_LOOP, our train ends here. */ | |
254 | if (pred_loop == def_loop) | |
255 | continue; | |
256 | } | |
257 | else if (! flow_loop_nested_p (pred_loop, def_loop)) | |
258 | pred = find_sibling_superloop (pred_loop, def_loop)->header; | |
259 | ||
260 | /* Add PRED to the LIVEIN set. PRED_VISITED is true if | |
261 | we had already added PRED to LIVEIN before. */ | |
262 | pred_visited = !bitmap_set_bit (live_exits, pred->index); | |
263 | ||
264 | /* If we have visited PRED before, don't add it to the worklist. | |
265 | If BB dominates PRED, then we're probably looking at a loop. | |
266 | We're only interested in looking up in the dominance tree | |
267 | because DEF_BB dominates all the uses. */ | |
268 | if (pred_visited || dominated_by_p (CDI_DOMINATORS, pred, bb)) | |
269 | continue; | |
270 | ||
9771b263 | 271 | worklist.quick_push (pred); |
01273677 SB |
272 | } |
273 | } | |
01273677 SB |
274 | |
275 | def_loop_exits = BITMAP_ALLOC (&loop_renamer_obstack); | |
99b1c316 | 276 | for (class loop *loop = def_loop; |
01273677 SB |
277 | loop != current_loops->tree_root; |
278 | loop = loop_outer (loop)) | |
279 | bitmap_ior_into (def_loop_exits, loop_exits[loop->num]); | |
280 | bitmap_and_into (live_exits, def_loop_exits); | |
281 | BITMAP_FREE (def_loop_exits); | |
282 | } | |
283 | ||
284 | /* Add a loop-closing PHI for VAR in basic block EXIT. */ | |
285 | ||
286 | static void | |
287 | add_exit_phi (basic_block exit, tree var) | |
288 | { | |
538dd0b7 | 289 | gphi *phi; |
c913f08a | 290 | edge e; |
628f6a4e | 291 | edge_iterator ei; |
c913f08a | 292 | |
01273677 SB |
293 | /* Check that at least one of the edges entering the EXIT block exits |
294 | the loop, or a superloop of that loop, that VAR is defined in. */ | |
b2b29377 | 295 | if (flag_checking) |
c913f08a | 296 | { |
b2b29377 MM |
297 | gimple *def_stmt = SSA_NAME_DEF_STMT (var); |
298 | basic_block def_bb = gimple_bb (def_stmt); | |
299 | FOR_EACH_EDGE (e, ei, exit->preds) | |
300 | { | |
99b1c316 | 301 | class loop *aloop = find_common_loop (def_bb->loop_father, |
b2b29377 MM |
302 | e->src->loop_father); |
303 | if (!flow_bb_inside_loop_p (aloop, e->dest)) | |
304 | break; | |
305 | } | |
306 | gcc_assert (e); | |
c913f08a ZD |
307 | } |
308 | ||
dcc748dd | 309 | phi = create_phi_node (NULL_TREE, exit); |
01273677 | 310 | create_new_def_for (var, phi, gimple_phi_result_ptr (phi)); |
628f6a4e | 311 | FOR_EACH_EDGE (e, ei, exit->preds) |
01273677 SB |
312 | add_phi_arg (phi, var, e, UNKNOWN_LOCATION); |
313 | ||
314 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
315 | { | |
316 | fprintf (dump_file, ";; Created LCSSA PHI: "); | |
317 | print_gimple_stmt (dump_file, phi, 0, dump_flags); | |
318 | } | |
c913f08a ZD |
319 | } |
320 | ||
321 | /* Add exit phis for VAR that is used in LIVEIN. | |
01273677 | 322 | Exits of the loops are stored in LOOP_EXITS. */ |
c913f08a ZD |
323 | |
324 | static void | |
01273677 | 325 | add_exit_phis_var (tree var, bitmap use_blocks, bitmap *loop_exits) |
c913f08a | 326 | { |
3cd8c58a | 327 | unsigned index; |
87c476a2 | 328 | bitmap_iterator bi; |
01273677 SB |
329 | basic_block def_bb = gimple_bb (SSA_NAME_DEF_STMT (var)); |
330 | bitmap live_exits = BITMAP_ALLOC (&loop_renamer_obstack); | |
c913f08a | 331 | |
ceb16be3 | 332 | gcc_checking_assert (! bitmap_bit_p (use_blocks, def_bb->index)); |
c913f08a | 333 | |
01273677 | 334 | compute_live_loop_exits (live_exits, use_blocks, loop_exits, def_bb); |
c913f08a | 335 | |
01273677 | 336 | EXECUTE_IF_SET_IN_BITMAP (live_exits, 0, index, bi) |
87c476a2 | 337 | { |
06e28de2 | 338 | add_exit_phi (BASIC_BLOCK_FOR_FN (cfun, index), var); |
87c476a2 | 339 | } |
c302207e | 340 | |
01273677 | 341 | BITMAP_FREE (live_exits); |
c913f08a ZD |
342 | } |
343 | ||
344 | /* Add exit phis for the names marked in NAMES_TO_RENAME. | |
345 | Exits of the loops are stored in EXITS. Sets of blocks where the ssa | |
346 | names are used are stored in USE_BLOCKS. */ | |
347 | ||
348 | static void | |
01273677 | 349 | add_exit_phis (bitmap names_to_rename, bitmap *use_blocks, bitmap *loop_exits) |
c913f08a ZD |
350 | { |
351 | unsigned i; | |
87c476a2 | 352 | bitmap_iterator bi; |
c913f08a | 353 | |
87c476a2 | 354 | EXECUTE_IF_SET_IN_BITMAP (names_to_rename, 0, i, bi) |
c913f08a ZD |
355 | { |
356 | add_exit_phis_var (ssa_name (i), use_blocks[i], loop_exits); | |
87c476a2 | 357 | } |
c913f08a ZD |
358 | } |
359 | ||
01273677 | 360 | /* Fill the array of bitmaps LOOP_EXITS with all loop exit edge targets. */ |
c913f08a | 361 | |
01273677 SB |
362 | static void |
363 | get_loops_exits (bitmap *loop_exits) | |
c913f08a | 364 | { |
99b1c316 | 365 | class loop *loop; |
01273677 | 366 | unsigned j; |
c913f08a ZD |
367 | edge e; |
368 | ||
f0bd40b1 | 369 | FOR_EACH_LOOP (loop, 0) |
c913f08a | 370 | { |
9771b263 | 371 | vec<edge> exit_edges = get_loop_exit_edges (loop); |
01273677 | 372 | loop_exits[loop->num] = BITMAP_ALLOC (&loop_renamer_obstack); |
9771b263 | 373 | FOR_EACH_VEC_ELT (exit_edges, j, e) |
01273677 | 374 | bitmap_set_bit (loop_exits[loop->num], e->dest->index); |
9771b263 | 375 | exit_edges.release (); |
c913f08a | 376 | } |
c913f08a ZD |
377 | } |
378 | ||
379 | /* For USE in BB, if it is used outside of the loop it is defined in, | |
380 | mark it for rewrite. Record basic block BB where it is used | |
4ba00e9d TV |
381 | to USE_BLOCKS. Record the ssa name index to NEED_PHIS bitmap. |
382 | Note that for USEs in phis, BB should be the src of the edge corresponding to | |
383 | the use, rather than the bb containing the phi. */ | |
c913f08a ZD |
384 | |
385 | static void | |
84d65814 DN |
386 | find_uses_to_rename_use (basic_block bb, tree use, bitmap *use_blocks, |
387 | bitmap need_phis) | |
c913f08a ZD |
388 | { |
389 | unsigned ver; | |
390 | basic_block def_bb; | |
99b1c316 | 391 | class loop *def_loop; |
c913f08a ZD |
392 | |
393 | if (TREE_CODE (use) != SSA_NAME) | |
394 | return; | |
395 | ||
396 | ver = SSA_NAME_VERSION (use); | |
726a989a | 397 | def_bb = gimple_bb (SSA_NAME_DEF_STMT (use)); |
c913f08a ZD |
398 | if (!def_bb) |
399 | return; | |
400 | def_loop = def_bb->loop_father; | |
401 | ||
d6e840ee | 402 | /* If the definition is not inside a loop, it is not interesting. */ |
9ba025a2 | 403 | if (!loop_outer (def_loop)) |
c913f08a ZD |
404 | return; |
405 | ||
d6e840ee RG |
406 | /* If the use is not outside of the loop it is defined in, it is not |
407 | interesting. */ | |
408 | if (flow_bb_inside_loop_p (def_loop, bb)) | |
409 | return; | |
410 | ||
c302207e SB |
411 | /* If we're seeing VER for the first time, we still have to allocate |
412 | a bitmap for its uses. */ | |
413 | if (bitmap_set_bit (need_phis, ver)) | |
414 | use_blocks[ver] = BITMAP_ALLOC (&loop_renamer_obstack); | |
c913f08a | 415 | bitmap_set_bit (use_blocks[ver], bb->index); |
c913f08a ZD |
416 | } |
417 | ||
eaef98f3 TV |
418 | /* For uses matching USE_FLAGS in STMT, mark names that are used outside of the |
419 | loop they are defined to rewrite. Record the set of blocks in which the ssa | |
420 | names are used to USE_BLOCKS, and the ssa names themselves to NEED_PHIS. */ | |
c913f08a ZD |
421 | |
422 | static void | |
355fe088 | 423 | find_uses_to_rename_stmt (gimple *stmt, bitmap *use_blocks, bitmap need_phis, |
eaef98f3 | 424 | int use_flags) |
c913f08a | 425 | { |
4c124b4c AM |
426 | ssa_op_iter iter; |
427 | tree var; | |
726a989a | 428 | basic_block bb = gimple_bb (stmt); |
c913f08a | 429 | |
b5b8b0ac AO |
430 | if (is_gimple_debug (stmt)) |
431 | return; | |
432 | ||
eaef98f3 TV |
433 | /* FOR_EACH_SSA_TREE_OPERAND iterator does not allows SSA_OP_VIRTUAL_USES |
434 | only. */ | |
435 | if (use_flags == SSA_OP_VIRTUAL_USES) | |
436 | { | |
437 | tree vuse = gimple_vuse (stmt); | |
438 | if (vuse != NULL_TREE) | |
439 | find_uses_to_rename_use (bb, gimple_vuse (stmt), use_blocks, need_phis); | |
440 | } | |
441 | else | |
442 | FOR_EACH_SSA_TREE_OPERAND (var, stmt, iter, use_flags) | |
443 | find_uses_to_rename_use (bb, var, use_blocks, need_phis); | |
c913f08a ZD |
444 | } |
445 | ||
eaef98f3 TV |
446 | /* Marks names matching USE_FLAGS that are used in BB and outside of the loop |
447 | they are defined in for rewrite. Records the set of blocks in which the ssa | |
448 | names are used to USE_BLOCKS. Record the SSA names that will | |
449 | need exit PHIs in NEED_PHIS. */ | |
c913f08a ZD |
450 | |
451 | static void | |
eaef98f3 TV |
452 | find_uses_to_rename_bb (basic_block bb, bitmap *use_blocks, bitmap need_phis, |
453 | int use_flags) | |
c913f08a | 454 | { |
2b271002 ZD |
455 | edge e; |
456 | edge_iterator ei; | |
eaef98f3 TV |
457 | bool do_virtuals = (use_flags & SSA_OP_VIRTUAL_USES) != 0; |
458 | bool do_nonvirtuals = (use_flags & SSA_OP_USE) != 0; | |
c913f08a | 459 | |
2b271002 | 460 | FOR_EACH_EDGE (e, ei, bb->succs) |
538dd0b7 DM |
461 | for (gphi_iterator bsi = gsi_start_phis (e->dest); !gsi_end_p (bsi); |
462 | gsi_next (&bsi)) | |
01273677 | 463 | { |
538dd0b7 | 464 | gphi *phi = bsi.phi (); |
eaef98f3 TV |
465 | bool virtual_p = virtual_operand_p (gimple_phi_result (phi)); |
466 | if ((virtual_p && do_virtuals) | |
467 | || (!virtual_p && do_nonvirtuals)) | |
636f59cf RB |
468 | find_uses_to_rename_use (bb, PHI_ARG_DEF_FROM_EDGE (phi, e), |
469 | use_blocks, need_phis); | |
01273677 | 470 | } |
b8698a0f | 471 | |
538dd0b7 DM |
472 | for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); |
473 | gsi_next (&bsi)) | |
eaef98f3 TV |
474 | find_uses_to_rename_stmt (gsi_stmt (bsi), use_blocks, need_phis, |
475 | use_flags); | |
2b271002 | 476 | } |
b8698a0f | 477 | |
eaef98f3 TV |
478 | /* Marks names matching USE_FLAGS that are used outside of the loop they are |
479 | defined in for rewrite. Records the set of blocks in which the ssa names are | |
480 | used to USE_BLOCKS. Record the SSA names that will need exit PHIs in | |
481 | NEED_PHIS. If CHANGED_BBS is not NULL, scan only blocks in this set. */ | |
2b271002 ZD |
482 | |
483 | static void | |
eaef98f3 TV |
484 | find_uses_to_rename (bitmap changed_bbs, bitmap *use_blocks, bitmap need_phis, |
485 | int use_flags) | |
2b271002 ZD |
486 | { |
487 | basic_block bb; | |
488 | unsigned index; | |
489 | bitmap_iterator bi; | |
c913f08a | 490 | |
789c34e3 RB |
491 | if (changed_bbs) |
492 | EXECUTE_IF_SET_IN_BITMAP (changed_bbs, 0, index, bi) | |
36d57986 RB |
493 | { |
494 | bb = BASIC_BLOCK_FOR_FN (cfun, index); | |
495 | if (bb) | |
496 | find_uses_to_rename_bb (bb, use_blocks, need_phis, use_flags); | |
497 | } | |
2b271002 | 498 | else |
11cd3bed | 499 | FOR_EACH_BB_FN (bb, cfun) |
eaef98f3 TV |
500 | find_uses_to_rename_bb (bb, use_blocks, need_phis, use_flags); |
501 | } | |
502 | ||
503 | /* Mark uses of DEF that are used outside of the loop they are defined in for | |
504 | rewrite. Record the set of blocks in which the ssa names are used to | |
505 | USE_BLOCKS. Record the SSA names that will need exit PHIs in NEED_PHIS. */ | |
506 | ||
507 | static void | |
508 | find_uses_to_rename_def (tree def, bitmap *use_blocks, bitmap need_phis) | |
509 | { | |
355fe088 | 510 | gimple *use_stmt; |
eaef98f3 TV |
511 | imm_use_iterator imm_iter; |
512 | ||
513 | FOR_EACH_IMM_USE_STMT (use_stmt, imm_iter, def) | |
514 | { | |
48d811eb JJ |
515 | if (is_gimple_debug (use_stmt)) |
516 | continue; | |
517 | ||
eaef98f3 TV |
518 | basic_block use_bb = gimple_bb (use_stmt); |
519 | ||
520 | use_operand_p use_p; | |
521 | FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter) | |
522 | { | |
523 | if (gimple_code (use_stmt) == GIMPLE_PHI) | |
524 | { | |
525 | edge e = gimple_phi_arg_edge (as_a <gphi *> (use_stmt), | |
526 | PHI_ARG_INDEX_FROM_USE (use_p)); | |
527 | use_bb = e->src; | |
528 | } | |
529 | find_uses_to_rename_use (use_bb, USE_FROM_PTR (use_p), use_blocks, | |
530 | need_phis); | |
531 | } | |
532 | } | |
533 | } | |
534 | ||
535 | /* Marks names matching USE_FLAGS that are defined in LOOP and used outside of | |
536 | it for rewrite. Records the set of blocks in which the ssa names are used to | |
537 | USE_BLOCKS. Record the SSA names that will need exit PHIs in NEED_PHIS. */ | |
538 | ||
539 | static void | |
99b1c316 | 540 | find_uses_to_rename_in_loop (class loop *loop, bitmap *use_blocks, |
eaef98f3 TV |
541 | bitmap need_phis, int use_flags) |
542 | { | |
543 | bool do_virtuals = (use_flags & SSA_OP_VIRTUAL_USES) != 0; | |
544 | bool do_nonvirtuals = (use_flags & SSA_OP_USE) != 0; | |
545 | int def_flags = ((do_virtuals ? SSA_OP_VIRTUAL_DEFS : 0) | |
546 | | (do_nonvirtuals ? SSA_OP_DEF : 0)); | |
547 | ||
548 | ||
549 | basic_block *bbs = get_loop_body (loop); | |
550 | ||
551 | for (unsigned int i = 0; i < loop->num_nodes; i++) | |
552 | { | |
553 | basic_block bb = bbs[i]; | |
554 | ||
555 | for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); | |
556 | gsi_next (&bsi)) | |
557 | { | |
558 | gphi *phi = bsi.phi (); | |
559 | tree res = gimple_phi_result (phi); | |
560 | bool virtual_p = virtual_operand_p (res); | |
561 | if ((virtual_p && do_virtuals) | |
562 | || (!virtual_p && do_nonvirtuals)) | |
563 | find_uses_to_rename_def (res, use_blocks, need_phis); | |
564 | } | |
565 | ||
566 | for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); | |
567 | gsi_next (&bsi)) | |
568 | { | |
355fe088 | 569 | gimple *stmt = gsi_stmt (bsi); |
eaef98f3 TV |
570 | /* FOR_EACH_SSA_TREE_OPERAND iterator does not allows |
571 | SSA_OP_VIRTUAL_DEFS only. */ | |
572 | if (def_flags == SSA_OP_VIRTUAL_DEFS) | |
573 | { | |
574 | tree vdef = gimple_vdef (stmt); | |
575 | if (vdef != NULL) | |
576 | find_uses_to_rename_def (vdef, use_blocks, need_phis); | |
577 | } | |
578 | else | |
579 | { | |
580 | tree var; | |
581 | ssa_op_iter iter; | |
582 | FOR_EACH_SSA_TREE_OPERAND (var, stmt, iter, def_flags) | |
583 | find_uses_to_rename_def (var, use_blocks, need_phis); | |
584 | } | |
585 | } | |
586 | } | |
587 | ||
588 | XDELETEVEC (bbs); | |
c913f08a ZD |
589 | } |
590 | ||
591 | /* Rewrites the program into a loop closed ssa form -- i.e. inserts extra | |
592 | phi nodes to ensure that no variable is used outside the loop it is | |
593 | defined in. | |
594 | ||
595 | This strengthening of the basic ssa form has several advantages: | |
596 | ||
597 | 1) Updating it during unrolling/peeling/versioning is trivial, since | |
598 | we do not need to care about the uses outside of the loop. | |
ceb16be3 RG |
599 | The same applies to virtual operands which are also rewritten into |
600 | loop closed SSA form. Note that virtual operands are always live | |
601 | until function exit. | |
c913f08a ZD |
602 | 2) The behavior of all uses of an induction variable is the same. |
603 | Without this, you need to distinguish the case when the variable | |
604 | is used outside of the loop it is defined in, for example | |
605 | ||
606 | for (i = 0; i < 100; i++) | |
607 | { | |
608 | for (j = 0; j < 100; j++) | |
609 | { | |
610 | k = i + j; | |
611 | use1 (k); | |
612 | } | |
613 | use2 (k); | |
614 | } | |
615 | ||
616 | Looking from the outer loop with the normal SSA form, the first use of k | |
617 | is not well-behaved, while the second one is an induction variable with | |
2b271002 | 618 | base 99 and step 1. |
b8698a0f | 619 | |
eaef98f3 TV |
620 | If LOOP is non-null, only rewrite uses that have defs in LOOP. Otherwise, |
621 | if CHANGED_BBS is not NULL, we look for uses outside loops only in the | |
622 | basic blocks in this set. | |
623 | ||
624 | USE_FLAGS allows us to specify whether we want virtual, non-virtual or | |
625 | both variables rewritten. | |
84d65814 DN |
626 | |
627 | UPDATE_FLAG is used in the call to update_ssa. See | |
628 | TODO_update_ssa* for documentation. */ | |
c913f08a ZD |
629 | |
630 | void | |
eaef98f3 | 631 | rewrite_into_loop_closed_ssa_1 (bitmap changed_bbs, unsigned update_flag, |
99b1c316 | 632 | int use_flags, class loop *loop) |
c913f08a | 633 | { |
c913f08a | 634 | bitmap *use_blocks; |
c7b852c8 ZD |
635 | bitmap names_to_rename; |
636 | ||
f87000d0 | 637 | loops_state_set (LOOP_CLOSED_SSA); |
0fc822d0 | 638 | if (number_of_loops (cfun) <= 1) |
c7b852c8 ZD |
639 | return; |
640 | ||
01273677 SB |
641 | /* If the pass has caused the SSA form to be out-of-date, update it |
642 | now. */ | |
a6c764d0 | 643 | if (update_flag != 0) |
eaef98f3 | 644 | update_ssa (update_flag); |
a6c764d0 MM |
645 | else if (flag_checking) |
646 | verify_ssa (true, true); | |
01273677 | 647 | |
c302207e SB |
648 | bitmap_obstack_initialize (&loop_renamer_obstack); |
649 | ||
c302207e | 650 | names_to_rename = BITMAP_ALLOC (&loop_renamer_obstack); |
c913f08a | 651 | |
c302207e SB |
652 | /* Uses of names to rename. We don't have to initialize this array, |
653 | because we know that we will only have entries for the SSA names | |
654 | in NAMES_TO_RENAME. */ | |
0fc4dd09 | 655 | use_blocks = XNEWVEC (bitmap, num_ssa_names); |
c913f08a | 656 | |
eaef98f3 TV |
657 | if (loop != NULL) |
658 | { | |
659 | gcc_assert (changed_bbs == NULL); | |
660 | find_uses_to_rename_in_loop (loop, use_blocks, names_to_rename, | |
661 | use_flags); | |
662 | } | |
663 | else | |
664 | { | |
665 | gcc_assert (loop == NULL); | |
666 | find_uses_to_rename (changed_bbs, use_blocks, names_to_rename, use_flags); | |
667 | } | |
2b271002 | 668 | |
3d741091 RB |
669 | if (!bitmap_empty_p (names_to_rename)) |
670 | { | |
671 | /* An array of bitmaps where LOOP_EXITS[I] is the set of basic blocks | |
672 | that are the destination of an edge exiting loop number I. */ | |
0fc822d0 | 673 | bitmap *loop_exits = XNEWVEC (bitmap, number_of_loops (cfun)); |
3d741091 RB |
674 | get_loops_exits (loop_exits); |
675 | ||
676 | /* Add the PHI nodes on exits of the loops for the names we need to | |
677 | rewrite. */ | |
678 | add_exit_phis (names_to_rename, use_blocks, loop_exits); | |
679 | ||
680 | free (loop_exits); | |
681 | ||
682 | /* Fix up all the names found to be used outside their original | |
683 | loops. */ | |
684 | update_ssa (TODO_update_ssa); | |
685 | } | |
c913f08a | 686 | |
c302207e | 687 | bitmap_obstack_release (&loop_renamer_obstack); |
c913f08a | 688 | free (use_blocks); |
c913f08a ZD |
689 | } |
690 | ||
eaef98f3 TV |
691 | /* Rewrites the non-virtual defs and uses into a loop closed ssa form. If |
692 | CHANGED_BBS is not NULL, we look for uses outside loops only in the basic | |
693 | blocks in this set. UPDATE_FLAG is used in the call to update_ssa. See | |
694 | TODO_update_ssa* for documentation. */ | |
338392ed | 695 | |
eaef98f3 TV |
696 | void |
697 | rewrite_into_loop_closed_ssa (bitmap changed_bbs, unsigned update_flag) | |
338392ed | 698 | { |
eaef98f3 | 699 | rewrite_into_loop_closed_ssa_1 (changed_bbs, update_flag, SSA_OP_USE, NULL); |
338392ed TV |
700 | } |
701 | ||
eaef98f3 TV |
702 | /* Rewrites virtual defs and uses with def in LOOP into loop closed ssa |
703 | form. */ | |
338392ed TV |
704 | |
705 | void | |
99b1c316 | 706 | rewrite_virtuals_into_loop_closed_ssa (class loop *loop) |
338392ed | 707 | { |
eaef98f3 | 708 | rewrite_into_loop_closed_ssa_1 (NULL, 0, SSA_OP_VIRTUAL_USES, loop); |
338392ed TV |
709 | } |
710 | ||
d80d5c38 | 711 | /* Check invariants of the loop closed ssa form for the def in DEF_BB. */ |
c913f08a ZD |
712 | |
713 | static void | |
d80d5c38 | 714 | check_loop_closed_ssa_def (basic_block def_bb, tree def) |
c913f08a | 715 | { |
d80d5c38 BC |
716 | use_operand_p use_p; |
717 | imm_use_iterator iterator; | |
718 | FOR_EACH_IMM_USE_FAST (use_p, iterator, def) | |
719 | { | |
720 | if (is_gimple_debug (USE_STMT (use_p))) | |
721 | continue; | |
b8698a0f | 722 | |
d80d5c38 BC |
723 | basic_block use_bb = gimple_bb (USE_STMT (use_p)); |
724 | if (is_a <gphi *> (USE_STMT (use_p))) | |
725 | use_bb = EDGE_PRED (use_bb, PHI_ARG_INDEX_FROM_USE (use_p))->src; | |
c913f08a | 726 | |
d80d5c38 BC |
727 | gcc_assert (flow_bb_inside_loop_p (def_bb->loop_father, use_bb)); |
728 | } | |
c913f08a ZD |
729 | } |
730 | ||
d80d5c38 | 731 | /* Checks invariants of loop closed ssa form in BB. */ |
c913f08a ZD |
732 | |
733 | static void | |
d80d5c38 | 734 | check_loop_closed_ssa_bb (basic_block bb) |
c913f08a | 735 | { |
d80d5c38 BC |
736 | for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); |
737 | gsi_next (&bsi)) | |
738 | { | |
739 | gphi *phi = bsi.phi (); | |
c913f08a | 740 | |
d80d5c38 BC |
741 | if (!virtual_operand_p (PHI_RESULT (phi))) |
742 | check_loop_closed_ssa_def (bb, PHI_RESULT (phi)); | |
743 | } | |
b5b8b0ac | 744 | |
d80d5c38 BC |
745 | for (gimple_stmt_iterator bsi = gsi_start_nondebug_bb (bb); !gsi_end_p (bsi); |
746 | gsi_next_nondebug (&bsi)) | |
747 | { | |
748 | ssa_op_iter iter; | |
749 | tree var; | |
750 | gimple *stmt = gsi_stmt (bsi); | |
751 | ||
752 | FOR_EACH_SSA_TREE_OPERAND (var, stmt, iter, SSA_OP_DEF) | |
753 | check_loop_closed_ssa_def (bb, var); | |
754 | } | |
c913f08a ZD |
755 | } |
756 | ||
a3b9e73c | 757 | /* Checks that invariants of the loop closed ssa form are preserved. |
d80d5c38 BC |
758 | Call verify_ssa when VERIFY_SSA_P is true. Note all loops are checked |
759 | if LOOP is NULL, otherwise, only LOOP is checked. */ | |
c913f08a | 760 | |
24e47c76 | 761 | DEBUG_FUNCTION void |
99b1c316 | 762 | verify_loop_closed_ssa (bool verify_ssa_p, class loop *loop) |
c913f08a | 763 | { |
0fc822d0 | 764 | if (number_of_loops (cfun) <= 1) |
84d65814 DN |
765 | return; |
766 | ||
a3b9e73c | 767 | if (verify_ssa_p) |
e9ff9caf | 768 | verify_ssa (false, true); |
c913f08a | 769 | |
a222c01a MM |
770 | timevar_push (TV_VERIFY_LOOP_CLOSED); |
771 | ||
d80d5c38 | 772 | if (loop == NULL) |
c913f08a | 773 | { |
d80d5c38 | 774 | basic_block bb; |
c913f08a | 775 | |
d80d5c38 BC |
776 | FOR_EACH_BB_FN (bb, cfun) |
777 | if (bb->loop_father && bb->loop_father->num > 0) | |
778 | check_loop_closed_ssa_bb (bb); | |
779 | } | |
780 | else | |
781 | { | |
782 | basic_block *bbs = get_loop_body (loop); | |
783 | ||
784 | for (unsigned i = 0; i < loop->num_nodes; ++i) | |
785 | check_loop_closed_ssa_bb (bbs[i]); | |
786 | ||
787 | free (bbs); | |
c913f08a | 788 | } |
a222c01a MM |
789 | |
790 | timevar_pop (TV_VERIFY_LOOP_CLOSED); | |
c913f08a | 791 | } |
8b11a64c ZD |
792 | |
793 | /* Split loop exit edge EXIT. The things are a bit complicated by a need to | |
733441e2 RB |
794 | preserve the loop closed ssa form. If COPY_CONSTANTS_P is true then |
795 | forwarder PHIs are also created for constant arguments. | |
796 | The newly created block is returned. */ | |
8b11a64c | 797 | |
5f40b3cb | 798 | basic_block |
733441e2 | 799 | split_loop_exit_edge (edge exit, bool copy_constants_p) |
8b11a64c ZD |
800 | { |
801 | basic_block dest = exit->dest; | |
598ec7bd | 802 | basic_block bb = split_edge (exit); |
538dd0b7 | 803 | gphi *phi, *new_phi; |
726a989a | 804 | tree new_name, name; |
8b11a64c | 805 | use_operand_p op_p; |
538dd0b7 | 806 | gphi_iterator psi; |
620e594b | 807 | location_t locus; |
8b11a64c | 808 | |
726a989a | 809 | for (psi = gsi_start_phis (dest); !gsi_end_p (psi); gsi_next (&psi)) |
8b11a64c | 810 | { |
538dd0b7 | 811 | phi = psi.phi (); |
c5cbcccf | 812 | op_p = PHI_ARG_DEF_PTR_FROM_EDGE (phi, single_succ_edge (bb)); |
f5045c96 | 813 | locus = gimple_phi_arg_location_from_edge (phi, single_succ_edge (bb)); |
8b11a64c | 814 | |
7fac6722 ZD |
815 | name = USE_FROM_PTR (op_p); |
816 | ||
38635499 | 817 | /* If the argument of the PHI node is a constant, we do not need |
7fac6722 | 818 | to keep it inside loop. */ |
733441e2 RB |
819 | if (TREE_CODE (name) != SSA_NAME |
820 | && !copy_constants_p) | |
7fac6722 ZD |
821 | continue; |
822 | ||
823 | /* Otherwise create an auxiliary phi node that will copy the value | |
38635499 | 824 | of the SSA name out of the loop. */ |
733441e2 | 825 | new_name = duplicate_ssa_name (PHI_RESULT (phi), NULL); |
8b11a64c | 826 | new_phi = create_phi_node (new_name, bb); |
9e227d60 | 827 | add_phi_arg (new_phi, name, exit, locus); |
8b11a64c ZD |
828 | SET_USE (op_p, new_name); |
829 | } | |
5f40b3cb ZD |
830 | |
831 | return bb; | |
8b11a64c ZD |
832 | } |
833 | ||
8b11a64c ZD |
834 | /* Returns the basic block in that statements should be emitted for induction |
835 | variables incremented at the end of the LOOP. */ | |
836 | ||
837 | basic_block | |
99b1c316 | 838 | ip_end_pos (class loop *loop) |
8b11a64c ZD |
839 | { |
840 | return loop->latch; | |
841 | } | |
842 | ||
843 | /* Returns the basic block in that statements should be emitted for induction | |
844 | variables incremented just before exit condition of a LOOP. */ | |
845 | ||
846 | basic_block | |
99b1c316 | 847 | ip_normal_pos (class loop *loop) |
8b11a64c | 848 | { |
355fe088 | 849 | gimple *last; |
8b11a64c ZD |
850 | basic_block bb; |
851 | edge exit; | |
852 | ||
c5cbcccf | 853 | if (!single_pred_p (loop->latch)) |
8b11a64c ZD |
854 | return NULL; |
855 | ||
c5cbcccf | 856 | bb = single_pred (loop->latch); |
8b11a64c | 857 | last = last_stmt (bb); |
ae2cf11b | 858 | if (!last |
726a989a | 859 | || gimple_code (last) != GIMPLE_COND) |
8b11a64c ZD |
860 | return NULL; |
861 | ||
628f6a4e | 862 | exit = EDGE_SUCC (bb, 0); |
8b11a64c | 863 | if (exit->dest == loop->latch) |
628f6a4e | 864 | exit = EDGE_SUCC (bb, 1); |
8b11a64c ZD |
865 | |
866 | if (flow_bb_inside_loop_p (loop, exit->dest)) | |
867 | return NULL; | |
868 | ||
869 | return bb; | |
870 | } | |
871 | ||
872 | /* Stores the standard position for induction variable increment in LOOP | |
873 | (just before the exit condition if it is available and latch block is empty, | |
874 | end of the latch block otherwise) to BSI. INSERT_AFTER is set to true if | |
875 | the increment should be inserted after *BSI. */ | |
876 | ||
877 | void | |
99b1c316 | 878 | standard_iv_increment_position (class loop *loop, gimple_stmt_iterator *bsi, |
8b11a64c ZD |
879 | bool *insert_after) |
880 | { | |
881 | basic_block bb = ip_normal_pos (loop), latch = ip_end_pos (loop); | |
355fe088 | 882 | gimple *last = last_stmt (latch); |
8b11a64c ZD |
883 | |
884 | if (!bb | |
726a989a | 885 | || (last && gimple_code (last) != GIMPLE_LABEL)) |
8b11a64c | 886 | { |
726a989a | 887 | *bsi = gsi_last_bb (latch); |
8b11a64c ZD |
888 | *insert_after = true; |
889 | } | |
890 | else | |
891 | { | |
726a989a | 892 | *bsi = gsi_last_bb (bb); |
8b11a64c ZD |
893 | *insert_after = false; |
894 | } | |
895 | } | |
92fc4a2f ZD |
896 | |
897 | /* Copies phi node arguments for duplicated blocks. The index of the first | |
898 | duplicated block is FIRST_NEW_BLOCK. */ | |
899 | ||
900 | static void | |
901 | copy_phi_node_args (unsigned first_new_block) | |
902 | { | |
903 | unsigned i; | |
904 | ||
8b1c6fd7 | 905 | for (i = first_new_block; i < (unsigned) last_basic_block_for_fn (cfun); i++) |
06e28de2 | 906 | BASIC_BLOCK_FOR_FN (cfun, i)->flags |= BB_DUPLICATED; |
92fc4a2f | 907 | |
8b1c6fd7 | 908 | for (i = first_new_block; i < (unsigned) last_basic_block_for_fn (cfun); i++) |
06e28de2 | 909 | add_phi_args_after_copy_bb (BASIC_BLOCK_FOR_FN (cfun, i)); |
92fc4a2f | 910 | |
8b1c6fd7 | 911 | for (i = first_new_block; i < (unsigned) last_basic_block_for_fn (cfun); i++) |
06e28de2 | 912 | BASIC_BLOCK_FOR_FN (cfun, i)->flags &= ~BB_DUPLICATED; |
92fc4a2f ZD |
913 | } |
914 | ||
92fc4a2f | 915 | |
84d65814 DN |
916 | /* The same as cfgloopmanip.c:duplicate_loop_to_header_edge, but also |
917 | updates the PHI nodes at start of the copied region. In order to | |
918 | achieve this, only loops whose exits all lead to the same location | |
919 | are handled. | |
92fc4a2f | 920 | |
84d65814 DN |
921 | Notice that we do not completely update the SSA web after |
922 | duplication. The caller is responsible for calling update_ssa | |
923 | after the loop has been duplicated. */ | |
92fc4a2f ZD |
924 | |
925 | bool | |
99b1c316 | 926 | gimple_duplicate_loop_to_header_edge (class loop *loop, edge e, |
92fc4a2f | 927 | unsigned int ndupl, sbitmap wont_exit, |
9771b263 | 928 | edge orig, vec<edge> *to_remove, |
ee8c1b05 | 929 | int flags) |
92fc4a2f ZD |
930 | { |
931 | unsigned first_new_block; | |
92fc4a2f | 932 | |
f87000d0 | 933 | if (!loops_state_satisfies_p (LOOPS_HAVE_SIMPLE_LATCHES)) |
92fc4a2f | 934 | return false; |
f87000d0 | 935 | if (!loops_state_satisfies_p (LOOPS_HAVE_PREHEADERS)) |
92fc4a2f ZD |
936 | return false; |
937 | ||
8b1c6fd7 | 938 | first_new_block = last_basic_block_for_fn (cfun); |
d73be268 | 939 | if (!duplicate_loop_to_header_edge (loop, e, ndupl, wont_exit, |
ee8c1b05 | 940 | orig, to_remove, flags)) |
92fc4a2f ZD |
941 | return false; |
942 | ||
943 | /* Readd the removed phi args for e. */ | |
71882046 | 944 | flush_pending_stmts (e); |
92fc4a2f ZD |
945 | |
946 | /* Copy the phi node arguments. */ | |
947 | copy_phi_node_args (first_new_block); | |
948 | ||
92fc4a2f | 949 | scev_reset (); |
92fc4a2f ZD |
950 | |
951 | return true; | |
952 | } | |
17684618 | 953 | |
17684618 ZD |
954 | /* Returns true if we can unroll LOOP FACTOR times. Number |
955 | of iterations of the loop is returned in NITER. */ | |
956 | ||
957 | bool | |
99b1c316 MS |
958 | can_unroll_loop_p (class loop *loop, unsigned factor, |
959 | class tree_niter_desc *niter) | |
17684618 ZD |
960 | { |
961 | edge exit; | |
962 | ||
963 | /* Check whether unrolling is possible. We only want to unroll loops | |
964 | for that we are able to determine number of iterations. We also | |
965 | want to split the extra iterations of the loop from its end, | |
966 | therefore we require that the loop has precisely one | |
967 | exit. */ | |
968 | ||
969 | exit = single_dom_exit (loop); | |
970 | if (!exit) | |
971 | return false; | |
972 | ||
973 | if (!number_of_iterations_exit (loop, exit, niter, false) | |
bf8dbe38 ZD |
974 | || niter->cmp == ERROR_MARK |
975 | /* Scalar evolutions analysis might have copy propagated | |
976 | the abnormal ssa names into these expressions, hence | |
2f8e468b | 977 | emitting the computations based on them during loop |
bf8dbe38 ZD |
978 | unrolling might create overlapping life ranges for |
979 | them, and failures in out-of-ssa. */ | |
980 | || contains_abnormal_ssa_name_p (niter->may_be_zero) | |
981 | || contains_abnormal_ssa_name_p (niter->control.base) | |
982 | || contains_abnormal_ssa_name_p (niter->control.step) | |
983 | || contains_abnormal_ssa_name_p (niter->bound)) | |
17684618 ZD |
984 | return false; |
985 | ||
986 | /* And of course, we must be able to duplicate the loop. */ | |
987 | if (!can_duplicate_loop_p (loop)) | |
988 | return false; | |
989 | ||
990 | /* The final loop should be small enough. */ | |
7f9bc51b | 991 | if (tree_num_loop_insns (loop, &eni_size_weights) * factor |
028d4092 | 992 | > (unsigned) param_max_unrolled_insns) |
17684618 ZD |
993 | return false; |
994 | ||
995 | return true; | |
996 | } | |
997 | ||
998 | /* Determines the conditions that control execution of LOOP unrolled FACTOR | |
999 | times. DESC is number of iterations of LOOP. ENTER_COND is set to | |
1000 | condition that must be true if the main loop can be entered. | |
1001 | EXIT_BASE, EXIT_STEP, EXIT_CMP and EXIT_BOUND are set to values describing | |
1002 | how the exit from the unrolled loop should be controlled. */ | |
1003 | ||
1004 | static void | |
99b1c316 | 1005 | determine_exit_conditions (class loop *loop, class tree_niter_desc *desc, |
17684618 ZD |
1006 | unsigned factor, tree *enter_cond, |
1007 | tree *exit_base, tree *exit_step, | |
1008 | enum tree_code *exit_cmp, tree *exit_bound) | |
1009 | { | |
726a989a | 1010 | gimple_seq stmts; |
17684618 ZD |
1011 | tree base = desc->control.base; |
1012 | tree step = desc->control.step; | |
1013 | tree bound = desc->bound; | |
d24a32a1 | 1014 | tree type = TREE_TYPE (step); |
17684618 ZD |
1015 | tree bigstep, delta; |
1016 | tree min = lower_bound_in_type (type, type); | |
1017 | tree max = upper_bound_in_type (type, type); | |
1018 | enum tree_code cmp = desc->cmp; | |
1019 | tree cond = boolean_true_node, assum; | |
1020 | ||
0d82a1c8 | 1021 | /* For pointers, do the arithmetics in the type of step. */ |
d24a32a1 ZD |
1022 | base = fold_convert (type, base); |
1023 | bound = fold_convert (type, bound); | |
1024 | ||
17684618 ZD |
1025 | *enter_cond = boolean_false_node; |
1026 | *exit_base = NULL_TREE; | |
1027 | *exit_step = NULL_TREE; | |
1028 | *exit_cmp = ERROR_MARK; | |
1029 | *exit_bound = NULL_TREE; | |
1030 | gcc_assert (cmp != ERROR_MARK); | |
1031 | ||
1032 | /* We only need to be correct when we answer question | |
1033 | "Do at least FACTOR more iterations remain?" in the unrolled loop. | |
1034 | Thus, transforming BASE + STEP * i <> BOUND to | |
1035 | BASE + STEP * i < BOUND is ok. */ | |
1036 | if (cmp == NE_EXPR) | |
1037 | { | |
1038 | if (tree_int_cst_sign_bit (step)) | |
1039 | cmp = GT_EXPR; | |
1040 | else | |
1041 | cmp = LT_EXPR; | |
1042 | } | |
1043 | else if (cmp == LT_EXPR) | |
1044 | { | |
1045 | gcc_assert (!tree_int_cst_sign_bit (step)); | |
1046 | } | |
1047 | else if (cmp == GT_EXPR) | |
1048 | { | |
1049 | gcc_assert (tree_int_cst_sign_bit (step)); | |
1050 | } | |
1051 | else | |
1052 | gcc_unreachable (); | |
1053 | ||
1054 | /* The main body of the loop may be entered iff: | |
1055 | ||
1056 | 1) desc->may_be_zero is false. | |
1057 | 2) it is possible to check that there are at least FACTOR iterations | |
1058 | of the loop, i.e., BOUND - step * FACTOR does not overflow. | |
1059 | 3) # of iterations is at least FACTOR */ | |
1060 | ||
6e682d7e | 1061 | if (!integer_zerop (desc->may_be_zero)) |
17684618 ZD |
1062 | cond = fold_build2 (TRUTH_AND_EXPR, boolean_type_node, |
1063 | invert_truthvalue (desc->may_be_zero), | |
1064 | cond); | |
1065 | ||
1066 | bigstep = fold_build2 (MULT_EXPR, type, step, | |
1067 | build_int_cst_type (type, factor)); | |
1068 | delta = fold_build2 (MINUS_EXPR, type, bigstep, step); | |
1069 | if (cmp == LT_EXPR) | |
1070 | assum = fold_build2 (GE_EXPR, boolean_type_node, | |
1071 | bound, | |
1072 | fold_build2 (PLUS_EXPR, type, min, delta)); | |
1073 | else | |
1074 | assum = fold_build2 (LE_EXPR, boolean_type_node, | |
1075 | bound, | |
1076 | fold_build2 (PLUS_EXPR, type, max, delta)); | |
1077 | cond = fold_build2 (TRUTH_AND_EXPR, boolean_type_node, assum, cond); | |
1078 | ||
1079 | bound = fold_build2 (MINUS_EXPR, type, bound, delta); | |
1080 | assum = fold_build2 (cmp, boolean_type_node, base, bound); | |
1081 | cond = fold_build2 (TRUTH_AND_EXPR, boolean_type_node, assum, cond); | |
1082 | ||
1083 | cond = force_gimple_operand (unshare_expr (cond), &stmts, false, NULL_TREE); | |
1084 | if (stmts) | |
726a989a | 1085 | gsi_insert_seq_on_edge_immediate (loop_preheader_edge (loop), stmts); |
17684618 ZD |
1086 | /* cond now may be a gimple comparison, which would be OK, but also any |
1087 | other gimple rhs (say a && b). In this case we need to force it to | |
1088 | operand. */ | |
1089 | if (!is_gimple_condexpr (cond)) | |
1090 | { | |
1091 | cond = force_gimple_operand (cond, &stmts, true, NULL_TREE); | |
1092 | if (stmts) | |
726a989a | 1093 | gsi_insert_seq_on_edge_immediate (loop_preheader_edge (loop), stmts); |
17684618 ZD |
1094 | } |
1095 | *enter_cond = cond; | |
1096 | ||
1097 | base = force_gimple_operand (unshare_expr (base), &stmts, true, NULL_TREE); | |
1098 | if (stmts) | |
726a989a | 1099 | gsi_insert_seq_on_edge_immediate (loop_preheader_edge (loop), stmts); |
17684618 ZD |
1100 | bound = force_gimple_operand (unshare_expr (bound), &stmts, true, NULL_TREE); |
1101 | if (stmts) | |
726a989a | 1102 | gsi_insert_seq_on_edge_immediate (loop_preheader_edge (loop), stmts); |
17684618 ZD |
1103 | |
1104 | *exit_base = base; | |
1105 | *exit_step = bigstep; | |
1106 | *exit_cmp = cmp; | |
1107 | *exit_bound = bound; | |
1108 | } | |
1109 | ||
14fa2cc0 ZD |
1110 | /* Scales the frequencies of all basic blocks in LOOP that are strictly |
1111 | dominated by BB by NUM/DEN. */ | |
1112 | ||
1113 | static void | |
99b1c316 | 1114 | scale_dominated_blocks_in_loop (class loop *loop, basic_block bb, |
2a006669 | 1115 | profile_count num, profile_count den) |
14fa2cc0 ZD |
1116 | { |
1117 | basic_block son; | |
1118 | ||
2a006669 | 1119 | if (!den.nonzero_p () && !(num == profile_count::zero ())) |
14fa2cc0 ZD |
1120 | return; |
1121 | ||
1122 | for (son = first_dom_son (CDI_DOMINATORS, bb); | |
1123 | son; | |
1124 | son = next_dom_son (CDI_DOMINATORS, son)) | |
1125 | { | |
1126 | if (!flow_bb_inside_loop_p (loop, son)) | |
1127 | continue; | |
2a006669 | 1128 | scale_bbs_frequencies_profile_count (&son, 1, num, den); |
14fa2cc0 ZD |
1129 | scale_dominated_blocks_in_loop (loop, son, num, den); |
1130 | } | |
1131 | } | |
1132 | ||
57fa080b BC |
1133 | /* Return estimated niter for LOOP after unrolling by FACTOR times. */ |
1134 | ||
1135 | gcov_type | |
99b1c316 | 1136 | niter_for_unrolled_loop (class loop *loop, unsigned factor) |
57fa080b BC |
1137 | { |
1138 | gcc_assert (factor != 0); | |
1139 | bool profile_p = false; | |
1140 | gcov_type est_niter = expected_loop_iterations_unbounded (loop, &profile_p); | |
3862ef76 RS |
1141 | /* Note that this is really CEIL (est_niter + 1, factor) - 1, where the |
1142 | "+ 1" converts latch iterations to loop iterations and the "- 1" | |
1143 | converts back. */ | |
57fa080b BC |
1144 | gcov_type new_est_niter = est_niter / factor; |
1145 | ||
e7a74006 JH |
1146 | if (est_niter == -1) |
1147 | return -1; | |
1148 | ||
57fa080b BC |
1149 | /* Without profile feedback, loops for which we do not know a better estimate |
1150 | are assumed to roll 10 times. When we unroll such loop, it appears to | |
1151 | roll too little, and it may even seem to be cold. To avoid this, we | |
1152 | ensure that the created loop appears to roll at least 5 times (but at | |
1153 | most as many times as before unrolling). Don't do adjustment if profile | |
1154 | feedback is present. */ | |
1155 | if (new_est_niter < 5 && !profile_p) | |
1156 | { | |
1157 | if (est_niter < 5) | |
1158 | new_est_niter = est_niter; | |
1159 | else | |
1160 | new_est_niter = 5; | |
1161 | } | |
1162 | ||
3862ef76 RS |
1163 | if (loop->any_upper_bound) |
1164 | { | |
1165 | /* As above, this is really CEIL (upper_bound + 1, factor) - 1. */ | |
1166 | widest_int bound = wi::udiv_floor (loop->nb_iterations_upper_bound, | |
1167 | factor); | |
1168 | if (wi::ltu_p (bound, new_est_niter)) | |
1169 | new_est_niter = bound.to_uhwi (); | |
1170 | } | |
1171 | ||
57fa080b BC |
1172 | return new_est_niter; |
1173 | } | |
1174 | ||
d73be268 ZD |
1175 | /* Unroll LOOP FACTOR times. DESC describes number of iterations of LOOP. |
1176 | EXIT is the exit of the loop to that DESC corresponds. | |
1177 | ||
17684618 ZD |
1178 | If N is number of iterations of the loop and MAY_BE_ZERO is the condition |
1179 | under that loop exits in the first iteration even if N != 0, | |
b8698a0f | 1180 | |
17684618 ZD |
1181 | while (1) |
1182 | { | |
1183 | x = phi (init, next); | |
1184 | ||
1185 | pre; | |
1186 | if (st) | |
1187 | break; | |
1188 | post; | |
1189 | } | |
1190 | ||
1191 | becomes (with possibly the exit conditions formulated a bit differently, | |
1192 | avoiding the need to create a new iv): | |
b8698a0f | 1193 | |
17684618 ZD |
1194 | if (MAY_BE_ZERO || N < FACTOR) |
1195 | goto rest; | |
1196 | ||
1197 | do | |
1198 | { | |
1199 | x = phi (init, next); | |
1200 | ||
1201 | pre; | |
1202 | post; | |
1203 | pre; | |
1204 | post; | |
1205 | ... | |
1206 | pre; | |
1207 | post; | |
1208 | N -= FACTOR; | |
b8698a0f | 1209 | |
17684618 ZD |
1210 | } while (N >= FACTOR); |
1211 | ||
1212 | rest: | |
1213 | init' = phi (init, x); | |
1214 | ||
1215 | while (1) | |
1216 | { | |
1217 | x = phi (init', next); | |
1218 | ||
1219 | pre; | |
1220 | if (st) | |
1221 | break; | |
1222 | post; | |
567b96ed | 1223 | } |
b8698a0f | 1224 | |
567b96ed ZD |
1225 | Before the loop is unrolled, TRANSFORM is called for it (only for the |
1226 | unrolled loop, but not for its versioned copy). DATA is passed to | |
1227 | TRANSFORM. */ | |
17684618 | 1228 | |
03cb2019 ZD |
1229 | /* Probability in % that the unrolled loop is entered. Just a guess. */ |
1230 | #define PROB_UNROLLED_LOOP_ENTERED 90 | |
1231 | ||
17684618 | 1232 | void |
99b1c316 MS |
1233 | tree_transform_and_unroll_loop (class loop *loop, unsigned factor, |
1234 | edge exit, class tree_niter_desc *desc, | |
567b96ed ZD |
1235 | transform_callback transform, |
1236 | void *data) | |
17684618 | 1237 | { |
538dd0b7 | 1238 | gcond *exit_if; |
726a989a | 1239 | tree ctr_before, ctr_after; |
17684618 ZD |
1240 | tree enter_main_cond, exit_base, exit_step, exit_bound; |
1241 | enum tree_code exit_cmp; | |
538dd0b7 DM |
1242 | gphi *phi_old_loop, *phi_new_loop, *phi_rest; |
1243 | gphi_iterator psi_old_loop, psi_new_loop; | |
70b5e7dc | 1244 | tree init, next, new_init; |
99b1c316 | 1245 | class loop *new_loop; |
17684618 ZD |
1246 | basic_block rest, exit_bb; |
1247 | edge old_entry, new_entry, old_latch, precond_edge, new_exit; | |
14fa2cc0 | 1248 | edge new_nonexit, e; |
726a989a | 1249 | gimple_stmt_iterator bsi; |
17684618 ZD |
1250 | use_operand_p op; |
1251 | bool ok; | |
1234ee19 JH |
1252 | unsigned i; |
1253 | profile_probability prob, prob_entry, scale_unrolled; | |
3995f3a2 | 1254 | profile_count freq_e, freq_h; |
57fa080b | 1255 | gcov_type new_est_niter = niter_for_unrolled_loop (loop, factor); |
8e08deeb | 1256 | unsigned irr = loop_preheader_edge (loop)->flags & EDGE_IRREDUCIBLE_LOOP; |
ef062b13 | 1257 | auto_vec<edge> to_remove; |
17684618 | 1258 | |
17684618 ZD |
1259 | determine_exit_conditions (loop, desc, factor, |
1260 | &enter_main_cond, &exit_base, &exit_step, | |
1261 | &exit_cmp, &exit_bound); | |
1262 | ||
03cb2019 ZD |
1263 | /* Let us assume that the unrolled loop is quite likely to be entered. */ |
1264 | if (integer_nonzerop (enter_main_cond)) | |
1234ee19 | 1265 | prob_entry = profile_probability::always (); |
03cb2019 | 1266 | else |
1234ee19 JH |
1267 | prob_entry = profile_probability::guessed_always () |
1268 | .apply_scale (PROB_UNROLLED_LOOP_ENTERED, 100); | |
03cb2019 ZD |
1269 | |
1270 | /* The values for scales should keep profile consistent, and somewhat close | |
1271 | to correct. | |
1272 | ||
1273 | TODO: The current value of SCALE_REST makes it appear that the loop that | |
1274 | is created by splitting the remaining iterations of the unrolled loop is | |
1275 | executed the same number of times as the original loop, and with the same | |
1276 | frequencies, which is obviously wrong. This does not appear to cause | |
1277 | problems, so we do not bother with fixing it for now. To make the profile | |
1278 | correct, we would need to change the probability of the exit edge of the | |
1279 | loop, and recompute the distribution of frequencies in its body because | |
1280 | of this change (scale the frequencies of blocks before and after the exit | |
1281 | by appropriate factors). */ | |
1282 | scale_unrolled = prob_entry; | |
03cb2019 | 1283 | |
1234ee19 JH |
1284 | new_loop = loop_version (loop, enter_main_cond, NULL, prob_entry, |
1285 | prob_entry.invert (), scale_unrolled, | |
af2bbc51 JH |
1286 | profile_probability::guessed_always (), |
1287 | true); | |
17684618 ZD |
1288 | gcc_assert (new_loop != NULL); |
1289 | update_ssa (TODO_update_ssa); | |
1290 | ||
14fa2cc0 ZD |
1291 | /* Prepare the cfg and update the phi nodes. Move the loop exit to the |
1292 | loop latch (and make its condition dummy, for the moment). */ | |
17684618 ZD |
1293 | rest = loop_preheader_edge (new_loop)->src; |
1294 | precond_edge = single_pred_edge (rest); | |
598ec7bd | 1295 | split_edge (loop_latch_edge (loop)); |
17684618 ZD |
1296 | exit_bb = single_pred (loop->latch); |
1297 | ||
14fa2cc0 ZD |
1298 | /* Since the exit edge will be removed, the frequency of all the blocks |
1299 | in the loop that are dominated by it must be scaled by | |
1300 | 1 / (1 - exit->probability). */ | |
357067f2 JH |
1301 | if (exit->probability.initialized_p ()) |
1302 | scale_dominated_blocks_in_loop (loop, exit->src, | |
1234ee19 JH |
1303 | /* We are scaling up here so probability |
1304 | does not fit. */ | |
2a006669 JH |
1305 | loop->header->count, |
1306 | loop->header->count | |
1307 | - loop->header->count.apply_probability | |
1308 | (exit->probability)); | |
14fa2cc0 | 1309 | |
726a989a RB |
1310 | bsi = gsi_last_bb (exit_bb); |
1311 | exit_if = gimple_build_cond (EQ_EXPR, integer_zero_node, | |
1312 | integer_zero_node, | |
1313 | NULL_TREE, NULL_TREE); | |
a9b77cd1 | 1314 | |
726a989a | 1315 | gsi_insert_after (&bsi, exit_if, GSI_NEW_STMT); |
8e08deeb | 1316 | new_exit = make_edge (exit_bb, rest, EDGE_FALSE_VALUE | irr); |
6270df4c | 1317 | rescan_loop_exit (new_exit, true, false); |
14fa2cc0 ZD |
1318 | |
1319 | /* Set the probability of new exit to the same of the old one. Fix | |
1320 | the frequency of the latch block, by scaling it back by | |
1321 | 1 - exit->probability. */ | |
14fa2cc0 | 1322 | new_exit->probability = exit->probability; |
17684618 | 1323 | new_nonexit = single_pred_edge (loop->latch); |
357067f2 | 1324 | new_nonexit->probability = exit->probability.invert (); |
17684618 | 1325 | new_nonexit->flags = EDGE_TRUE_VALUE; |
357067f2 | 1326 | if (new_nonexit->probability.initialized_p ()) |
1234ee19 | 1327 | scale_bbs_frequencies (&loop->latch, 1, new_nonexit->probability); |
17684618 ZD |
1328 | |
1329 | old_entry = loop_preheader_edge (loop); | |
1330 | new_entry = loop_preheader_edge (new_loop); | |
1331 | old_latch = loop_latch_edge (loop); | |
726a989a RB |
1332 | for (psi_old_loop = gsi_start_phis (loop->header), |
1333 | psi_new_loop = gsi_start_phis (new_loop->header); | |
1334 | !gsi_end_p (psi_old_loop); | |
1335 | gsi_next (&psi_old_loop), gsi_next (&psi_new_loop)) | |
17684618 | 1336 | { |
538dd0b7 DM |
1337 | phi_old_loop = psi_old_loop.phi (); |
1338 | phi_new_loop = psi_new_loop.phi (); | |
726a989a | 1339 | |
17684618 ZD |
1340 | init = PHI_ARG_DEF_FROM_EDGE (phi_old_loop, old_entry); |
1341 | op = PHI_ARG_DEF_PTR_FROM_EDGE (phi_new_loop, new_entry); | |
1342 | gcc_assert (operand_equal_for_phi_arg_p (init, USE_FROM_PTR (op))); | |
1343 | next = PHI_ARG_DEF_FROM_EDGE (phi_old_loop, old_latch); | |
1344 | ||
1345 | /* Prefer using original variable as a base for the new ssa name. | |
1346 | This is necessary for virtual ops, and useful in order to avoid | |
1347 | losing debug info for real ops. */ | |
182e00b1 RG |
1348 | if (TREE_CODE (next) == SSA_NAME |
1349 | && useless_type_conversion_p (TREE_TYPE (next), | |
1350 | TREE_TYPE (init))) | |
b731b390 | 1351 | new_init = copy_ssa_name (next); |
182e00b1 RG |
1352 | else if (TREE_CODE (init) == SSA_NAME |
1353 | && useless_type_conversion_p (TREE_TYPE (init), | |
1354 | TREE_TYPE (next))) | |
b731b390 | 1355 | new_init = copy_ssa_name (init); |
182e00b1 | 1356 | else if (useless_type_conversion_p (TREE_TYPE (next), TREE_TYPE (init))) |
70b5e7dc | 1357 | new_init = make_temp_ssa_name (TREE_TYPE (next), NULL, "unrinittmp"); |
17684618 | 1358 | else |
70b5e7dc | 1359 | new_init = make_temp_ssa_name (TREE_TYPE (init), NULL, "unrinittmp"); |
17684618 | 1360 | |
17684618 | 1361 | phi_rest = create_phi_node (new_init, rest); |
17684618 | 1362 | |
9e227d60 DC |
1363 | add_phi_arg (phi_rest, init, precond_edge, UNKNOWN_LOCATION); |
1364 | add_phi_arg (phi_rest, next, new_exit, UNKNOWN_LOCATION); | |
17684618 ZD |
1365 | SET_USE (op, new_init); |
1366 | } | |
1367 | ||
14fa2cc0 ZD |
1368 | remove_path (exit); |
1369 | ||
567b96ed ZD |
1370 | /* Transform the loop. */ |
1371 | if (transform) | |
1372 | (*transform) (loop, data); | |
1373 | ||
14fa2cc0 ZD |
1374 | /* Unroll the loop and remove the exits in all iterations except for the |
1375 | last one. */ | |
7ba9e72d | 1376 | auto_sbitmap wont_exit (factor); |
f61e445a | 1377 | bitmap_ones (wont_exit); |
d7c028c0 | 1378 | bitmap_clear_bit (wont_exit, factor - 1); |
14fa2cc0 | 1379 | |
726a989a | 1380 | ok = gimple_duplicate_loop_to_header_edge |
567b96ed | 1381 | (loop, loop_latch_edge (loop), factor - 1, |
14fa2cc0 | 1382 | wont_exit, new_exit, &to_remove, DLTHE_FLAG_UPDATE_FREQ); |
567b96ed | 1383 | gcc_assert (ok); |
14fa2cc0 | 1384 | |
9771b263 | 1385 | FOR_EACH_VEC_ELT (to_remove, i, e) |
14fa2cc0 ZD |
1386 | { |
1387 | ok = remove_path (e); | |
1388 | gcc_assert (ok); | |
1389 | } | |
567b96ed ZD |
1390 | update_ssa (TODO_update_ssa); |
1391 | ||
1392 | /* Ensure that the frequencies in the loop match the new estimated | |
1393 | number of iterations, and change the probability of the new | |
1394 | exit edge. */ | |
57fa080b BC |
1395 | |
1396 | freq_h = loop->header->count; | |
ef30ab83 | 1397 | freq_e = (loop_preheader_edge (loop))->count (); |
e7a74006 | 1398 | if (freq_h.nonzero_p ()) |
57fa080b | 1399 | { |
57fa080b BC |
1400 | /* Avoid dropping loop body profile counter to 0 because of zero count |
1401 | in loop's preheader. */ | |
29c02e65 JH |
1402 | if (freq_h.nonzero_p () && !(freq_e == profile_count::zero ())) |
1403 | freq_e = freq_e.force_nonzero (); | |
af2bbc51 | 1404 | scale_loop_frequencies (loop, freq_e.probability_in (freq_h)); |
57fa080b | 1405 | } |
567b96ed ZD |
1406 | |
1407 | exit_bb = single_pred (loop->latch); | |
1408 | new_exit = find_edge (exit_bb, rest); | |
357067f2 JH |
1409 | new_exit->probability = profile_probability::always () |
1410 | .apply_scale (1, new_est_niter + 1); | |
567b96ed | 1411 | |
ef30ab83 | 1412 | rest->count += new_exit->count (); |
567b96ed ZD |
1413 | |
1414 | new_nonexit = single_pred_edge (loop->latch); | |
1234ee19 | 1415 | prob = new_nonexit->probability; |
357067f2 | 1416 | new_nonexit->probability = new_exit->probability.invert (); |
1234ee19 JH |
1417 | prob = new_nonexit->probability / prob; |
1418 | if (prob.initialized_p ()) | |
1419 | scale_bbs_frequencies (&loop->latch, 1, prob); | |
567b96ed | 1420 | |
17684618 ZD |
1421 | /* Finally create the new counter for number of iterations and add the new |
1422 | exit instruction. */ | |
22963fee | 1423 | bsi = gsi_last_nondebug_bb (exit_bb); |
538dd0b7 | 1424 | exit_if = as_a <gcond *> (gsi_stmt (bsi)); |
17684618 | 1425 | create_iv (exit_base, exit_step, NULL_TREE, loop, |
567b96ed | 1426 | &bsi, false, &ctr_before, &ctr_after); |
726a989a RB |
1427 | gimple_cond_set_code (exit_if, exit_cmp); |
1428 | gimple_cond_set_lhs (exit_if, ctr_after); | |
1429 | gimple_cond_set_rhs (exit_if, exit_bound); | |
567b96ed | 1430 | update_stmt (exit_if); |
17684618 | 1431 | |
b2b29377 MM |
1432 | checking_verify_flow_info (); |
1433 | checking_verify_loop_structure (); | |
d80d5c38 BC |
1434 | checking_verify_loop_closed_ssa (true, loop); |
1435 | checking_verify_loop_closed_ssa (true, new_loop); | |
17684618 | 1436 | } |
567b96ed ZD |
1437 | |
1438 | /* Wrapper over tree_transform_and_unroll_loop for case we do not | |
1439 | want to transform the loop before unrolling. The meaning | |
1440 | of the arguments is the same as for tree_transform_and_unroll_loop. */ | |
1441 | ||
1442 | void | |
99b1c316 MS |
1443 | tree_unroll_loop (class loop *loop, unsigned factor, |
1444 | edge exit, class tree_niter_desc *desc) | |
567b96ed ZD |
1445 | { |
1446 | tree_transform_and_unroll_loop (loop, factor, exit, desc, | |
1447 | NULL, NULL); | |
1448 | } | |
08dab97a RL |
1449 | |
1450 | /* Rewrite the phi node at position PSI in function of the main | |
1451 | induction variable MAIN_IV and insert the generated code at GSI. */ | |
1452 | ||
1453 | static void | |
1454 | rewrite_phi_with_iv (loop_p loop, | |
538dd0b7 | 1455 | gphi_iterator *psi, |
08dab97a RL |
1456 | gimple_stmt_iterator *gsi, |
1457 | tree main_iv) | |
1458 | { | |
1459 | affine_iv iv; | |
538dd0b7 DM |
1460 | gassign *stmt; |
1461 | gphi *phi = psi->phi (); | |
08dab97a RL |
1462 | tree atype, mtype, val, res = PHI_RESULT (phi); |
1463 | ||
ea057359 | 1464 | if (virtual_operand_p (res) || res == main_iv) |
08dab97a RL |
1465 | { |
1466 | gsi_next (psi); | |
1467 | return; | |
1468 | } | |
1469 | ||
1470 | if (!simple_iv (loop, loop, res, &iv, true)) | |
1471 | { | |
1472 | gsi_next (psi); | |
1473 | return; | |
1474 | } | |
1475 | ||
1476 | remove_phi_node (psi, false); | |
1477 | ||
1478 | atype = TREE_TYPE (res); | |
1479 | mtype = POINTER_TYPE_P (atype) ? sizetype : atype; | |
1480 | val = fold_build2 (MULT_EXPR, mtype, unshare_expr (iv.step), | |
1481 | fold_convert (mtype, main_iv)); | |
1482 | val = fold_build2 (POINTER_TYPE_P (atype) | |
1483 | ? POINTER_PLUS_EXPR : PLUS_EXPR, | |
1484 | atype, unshare_expr (iv.base), val); | |
1485 | val = force_gimple_operand_gsi (gsi, val, false, NULL_TREE, true, | |
1486 | GSI_SAME_STMT); | |
1487 | stmt = gimple_build_assign (res, val); | |
1488 | gsi_insert_before (gsi, stmt, GSI_SAME_STMT); | |
08dab97a RL |
1489 | } |
1490 | ||
1491 | /* Rewrite all the phi nodes of LOOP in function of the main induction | |
1492 | variable MAIN_IV. */ | |
1493 | ||
1494 | static void | |
1495 | rewrite_all_phi_nodes_with_iv (loop_p loop, tree main_iv) | |
1496 | { | |
1497 | unsigned i; | |
1498 | basic_block *bbs = get_loop_body_in_dom_order (loop); | |
538dd0b7 | 1499 | gphi_iterator psi; |
08dab97a RL |
1500 | |
1501 | for (i = 0; i < loop->num_nodes; i++) | |
1502 | { | |
1503 | basic_block bb = bbs[i]; | |
1504 | gimple_stmt_iterator gsi = gsi_after_labels (bb); | |
1505 | ||
1506 | if (bb->loop_father != loop) | |
1507 | continue; | |
1508 | ||
1509 | for (psi = gsi_start_phis (bb); !gsi_end_p (psi); ) | |
1510 | rewrite_phi_with_iv (loop, &psi, &gsi, main_iv); | |
1511 | } | |
1512 | ||
1513 | free (bbs); | |
1514 | } | |
1515 | ||
b092fe39 TV |
1516 | /* Bases all the induction variables in LOOP on a single induction variable |
1517 | (with base 0 and step 1), whose final value is compared with *NIT. When the | |
1518 | IV type precision has to be larger than *NIT type precision, *NIT is | |
1519 | converted to the larger type, the conversion code is inserted before the | |
1520 | loop, and *NIT is updated to the new definition. When BUMP_IN_LATCH is true, | |
1521 | the induction variable is incremented in the loop latch, otherwise it is | |
1522 | incremented in the loop header. Return the induction variable that was | |
1523 | created. */ | |
08dab97a RL |
1524 | |
1525 | tree | |
99b1c316 | 1526 | canonicalize_loop_ivs (class loop *loop, tree *nit, bool bump_in_latch) |
08dab97a RL |
1527 | { |
1528 | unsigned precision = TYPE_PRECISION (TREE_TYPE (*nit)); | |
1529 | unsigned original_precision = precision; | |
1530 | tree type, var_before; | |
538dd0b7 DM |
1531 | gimple_stmt_iterator gsi; |
1532 | gphi_iterator psi; | |
1533 | gcond *stmt; | |
08dab97a RL |
1534 | edge exit = single_dom_exit (loop); |
1535 | gimple_seq stmts; | |
3689198d | 1536 | bool unsigned_p = false; |
08dab97a RL |
1537 | |
1538 | for (psi = gsi_start_phis (loop->header); | |
1539 | !gsi_end_p (psi); gsi_next (&psi)) | |
1540 | { | |
538dd0b7 | 1541 | gphi *phi = psi.phi (); |
08dab97a | 1542 | tree res = PHI_RESULT (phi); |
3689198d | 1543 | bool uns; |
08dab97a | 1544 | |
3689198d | 1545 | type = TREE_TYPE (res); |
ea057359 | 1546 | if (virtual_operand_p (res) |
3689198d SP |
1547 | || (!INTEGRAL_TYPE_P (type) |
1548 | && !POINTER_TYPE_P (type)) | |
1549 | || TYPE_PRECISION (type) < precision) | |
1550 | continue; | |
1551 | ||
1552 | uns = POINTER_TYPE_P (type) | TYPE_UNSIGNED (type); | |
1553 | ||
1554 | if (TYPE_PRECISION (type) > precision) | |
1555 | unsigned_p = uns; | |
1556 | else | |
1557 | unsigned_p |= uns; | |
1558 | ||
1559 | precision = TYPE_PRECISION (type); | |
08dab97a RL |
1560 | } |
1561 | ||
f67f4dff | 1562 | scalar_int_mode mode = smallest_int_mode_for_size (precision); |
3689198d SP |
1563 | precision = GET_MODE_PRECISION (mode); |
1564 | type = build_nonstandard_integer_type (precision, unsigned_p); | |
08dab97a | 1565 | |
60f02f90 TV |
1566 | if (original_precision != precision |
1567 | || TYPE_UNSIGNED (TREE_TYPE (*nit)) != unsigned_p) | |
08dab97a RL |
1568 | { |
1569 | *nit = fold_convert (type, *nit); | |
1570 | *nit = force_gimple_operand (*nit, &stmts, true, NULL_TREE); | |
1571 | if (stmts) | |
1572 | gsi_insert_seq_on_edge_immediate (loop_preheader_edge (loop), stmts); | |
1573 | } | |
1574 | ||
f5b77e7d JJ |
1575 | if (bump_in_latch) |
1576 | gsi = gsi_last_bb (loop->latch); | |
1577 | else | |
1578 | gsi = gsi_last_nondebug_bb (loop->header); | |
08dab97a | 1579 | create_iv (build_int_cst_type (type, 0), build_int_cst (type, 1), NULL_TREE, |
c80a5403 | 1580 | loop, &gsi, bump_in_latch, &var_before, NULL); |
08dab97a RL |
1581 | |
1582 | rewrite_all_phi_nodes_with_iv (loop, var_before); | |
1583 | ||
538dd0b7 | 1584 | stmt = as_a <gcond *> (last_stmt (exit->src)); |
08dab97a RL |
1585 | /* Make the loop exit if the control condition is not satisfied. */ |
1586 | if (exit->flags & EDGE_TRUE_VALUE) | |
1587 | { | |
1588 | edge te, fe; | |
1589 | ||
1590 | extract_true_false_edges_from_block (exit->src, &te, &fe); | |
1591 | te->flags = EDGE_FALSE_VALUE; | |
1592 | fe->flags = EDGE_TRUE_VALUE; | |
1593 | } | |
1594 | gimple_cond_set_code (stmt, LT_EXPR); | |
1595 | gimple_cond_set_lhs (stmt, var_before); | |
1596 | gimple_cond_set_rhs (stmt, *nit); | |
1597 | update_stmt (stmt); | |
1598 | ||
1599 | return var_before; | |
1600 | } |