Print this page
rev 7077 : 8066763: fatal error "assert(false) failed: unexpected yanked node" in postaloc.cpp:139
Summary: Check for dead input nodes after replacing compare node with implicit null check.
Reviewed-by: kvn
| Split |
Split |
Close |
| Expand all |
| Collapse all |
--- old/hotspot/src/share/vm/opto/lcm.cpp
+++ new/hotspot/src/share/vm/opto/lcm.cpp
1 1 /*
2 2 * Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
3 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 4 *
5 5 * This code is free software; you can redistribute it and/or modify it
6 6 * under the terms of the GNU General Public License version 2 only, as
7 7 * published by the Free Software Foundation.
8 8 *
9 9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 12 * version 2 for more details (a copy is included in the LICENSE file that
13 13 * accompanied this code).
14 14 *
15 15 * You should have received a copy of the GNU General Public License version
16 16 * 2 along with this work; if not, write to the Free Software Foundation,
17 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 18 *
19 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 20 * or visit www.oracle.com if you need additional information or have any
21 21 * questions.
22 22 *
23 23 */
24 24
25 25 #include "precompiled.hpp"
26 26 #include "memory/allocation.inline.hpp"
27 27 #include "opto/block.hpp"
28 28 #include "opto/c2compiler.hpp"
29 29 #include "opto/callnode.hpp"
30 30 #include "opto/cfgnode.hpp"
31 31 #include "opto/machnode.hpp"
32 32 #include "opto/runtime.hpp"
33 33 #ifdef TARGET_ARCH_MODEL_x86_32
34 34 # include "adfiles/ad_x86_32.hpp"
35 35 #endif
36 36 #ifdef TARGET_ARCH_MODEL_x86_64
37 37 # include "adfiles/ad_x86_64.hpp"
38 38 #endif
39 39 #ifdef TARGET_ARCH_MODEL_sparc
40 40 # include "adfiles/ad_sparc.hpp"
41 41 #endif
42 42 #ifdef TARGET_ARCH_MODEL_zero
43 43 # include "adfiles/ad_zero.hpp"
44 44 #endif
45 45 #ifdef TARGET_ARCH_MODEL_arm
46 46 # include "adfiles/ad_arm.hpp"
47 47 #endif
48 48 #ifdef TARGET_ARCH_MODEL_ppc_32
49 49 # include "adfiles/ad_ppc_32.hpp"
50 50 #endif
51 51 #ifdef TARGET_ARCH_MODEL_ppc_64
52 52 # include "adfiles/ad_ppc_64.hpp"
53 53 #endif
54 54
55 55 // Optimization - Graph Style
56 56
57 57 // Check whether val is not-null-decoded compressed oop,
58 58 // i.e. will grab into the base of the heap if it represents NULL.
59 59 static bool accesses_heap_base_zone(Node *val) {
60 60 if (Universe::narrow_oop_base() > 0) { // Implies UseCompressedOops.
61 61 if (val && val->is_Mach()) {
62 62 if (val->as_Mach()->ideal_Opcode() == Op_DecodeN) {
63 63 // This assumes all Decodes with TypePtr::NotNull are matched to nodes that
64 64 // decode NULL to point to the heap base (Decode_NN).
65 65 if (val->bottom_type()->is_oopptr()->ptr() == TypePtr::NotNull) {
66 66 return true;
67 67 }
68 68 }
69 69 // Must recognize load operation with Decode matched in memory operand.
70 70 // We should not reach here exept for PPC/AIX, as os::zero_page_read_protected()
71 71 // returns true everywhere else. On PPC, no such memory operands
72 72 // exist, therefore we did not yet implement a check for such operands.
73 73 NOT_AIX(Unimplemented());
74 74 }
75 75 }
76 76 return false;
77 77 }
78 78
79 79 static bool needs_explicit_null_check_for_read(Node *val) {
80 80 // On some OSes (AIX) the page at address 0 is only write protected.
81 81 // If so, only Store operations will trap.
82 82 if (os::zero_page_read_protected()) {
83 83 return false; // Implicit null check will work.
84 84 }
85 85 // Also a read accessing the base of a heap-based compressed heap will trap.
86 86 if (accesses_heap_base_zone(val) && // Hits the base zone page.
87 87 Universe::narrow_oop_use_implicit_null_checks()) { // Base zone page is protected.
88 88 return false;
89 89 }
90 90
91 91 return true;
92 92 }
93 93
94 94 //------------------------------implicit_null_check----------------------------
95 95 // Detect implicit-null-check opportunities. Basically, find NULL checks
96 96 // with suitable memory ops nearby. Use the memory op to do the NULL check.
97 97 // I can generate a memory op if there is not one nearby.
98 98 // The proj is the control projection for the not-null case.
99 99 // The val is the pointer being checked for nullness or
100 100 // decodeHeapOop_not_null node if it did not fold into address.
101 101 void PhaseCFG::implicit_null_check(Block* block, Node *proj, Node *val, int allowed_reasons) {
102 102 // Assume if null check need for 0 offset then always needed
103 103 // Intel solaris doesn't support any null checks yet and no
104 104 // mechanism exists (yet) to set the switches at an os_cpu level
105 105 if( !ImplicitNullChecks || MacroAssembler::needs_explicit_null_check(0)) return;
106 106
107 107 // Make sure the ptr-is-null path appears to be uncommon!
108 108 float f = block->end()->as_MachIf()->_prob;
109 109 if( proj->Opcode() == Op_IfTrue ) f = 1.0f - f;
110 110 if( f > PROB_UNLIKELY_MAG(4) ) return;
111 111
112 112 uint bidx = 0; // Capture index of value into memop
113 113 bool was_store; // Memory op is a store op
114 114
115 115 // Get the successor block for if the test ptr is non-null
116 116 Block* not_null_block; // this one goes with the proj
117 117 Block* null_block;
118 118 if (block->get_node(block->number_of_nodes()-1) == proj) {
119 119 null_block = block->_succs[0];
120 120 not_null_block = block->_succs[1];
121 121 } else {
122 122 assert(block->get_node(block->number_of_nodes()-2) == proj, "proj is one or the other");
123 123 not_null_block = block->_succs[0];
124 124 null_block = block->_succs[1];
125 125 }
126 126 while (null_block->is_Empty() == Block::empty_with_goto) {
127 127 null_block = null_block->_succs[0];
128 128 }
129 129
130 130 // Search the exception block for an uncommon trap.
131 131 // (See Parse::do_if and Parse::do_ifnull for the reason
132 132 // we need an uncommon trap. Briefly, we need a way to
133 133 // detect failure of this optimization, as in 6366351.)
134 134 {
135 135 bool found_trap = false;
136 136 for (uint i1 = 0; i1 < null_block->number_of_nodes(); i1++) {
137 137 Node* nn = null_block->get_node(i1);
138 138 if (nn->is_MachCall() &&
139 139 nn->as_MachCall()->entry_point() == SharedRuntime::uncommon_trap_blob()->entry_point()) {
140 140 const Type* trtype = nn->in(TypeFunc::Parms)->bottom_type();
141 141 if (trtype->isa_int() && trtype->is_int()->is_con()) {
142 142 jint tr_con = trtype->is_int()->get_con();
143 143 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(tr_con);
144 144 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(tr_con);
145 145 assert((int)reason < (int)BitsPerInt, "recode bit map");
146 146 if (is_set_nth_bit(allowed_reasons, (int) reason)
147 147 && action != Deoptimization::Action_none) {
148 148 // This uncommon trap is sure to recompile, eventually.
149 149 // When that happens, C->too_many_traps will prevent
150 150 // this transformation from happening again.
151 151 found_trap = true;
152 152 }
153 153 }
154 154 break;
155 155 }
156 156 }
157 157 if (!found_trap) {
158 158 // We did not find an uncommon trap.
159 159 return;
160 160 }
161 161 }
162 162
163 163 // Check for decodeHeapOop_not_null node which did not fold into address
164 164 bool is_decoden = ((intptr_t)val) & 1;
165 165 val = (Node*)(((intptr_t)val) & ~1);
166 166
167 167 assert(!is_decoden || (val->in(0) == NULL) && val->is_Mach() &&
168 168 (val->as_Mach()->ideal_Opcode() == Op_DecodeN), "sanity");
169 169
170 170 // Search the successor block for a load or store who's base value is also
171 171 // the tested value. There may be several.
172 172 Node_List *out = new Node_List(Thread::current()->resource_area());
173 173 MachNode *best = NULL; // Best found so far
174 174 for (DUIterator i = val->outs(); val->has_out(i); i++) {
175 175 Node *m = val->out(i);
176 176 if( !m->is_Mach() ) continue;
177 177 MachNode *mach = m->as_Mach();
178 178 was_store = false;
179 179 int iop = mach->ideal_Opcode();
180 180 switch( iop ) {
181 181 case Op_LoadB:
182 182 case Op_LoadUB:
183 183 case Op_LoadUS:
184 184 case Op_LoadD:
185 185 case Op_LoadF:
186 186 case Op_LoadI:
187 187 case Op_LoadL:
188 188 case Op_LoadP:
189 189 case Op_LoadN:
190 190 case Op_LoadS:
191 191 case Op_LoadKlass:
192 192 case Op_LoadNKlass:
193 193 case Op_LoadRange:
194 194 case Op_LoadD_unaligned:
195 195 case Op_LoadL_unaligned:
196 196 assert(mach->in(2) == val, "should be address");
197 197 break;
198 198 case Op_StoreB:
199 199 case Op_StoreC:
200 200 case Op_StoreCM:
201 201 case Op_StoreD:
202 202 case Op_StoreF:
203 203 case Op_StoreI:
204 204 case Op_StoreL:
205 205 case Op_StoreP:
206 206 case Op_StoreN:
207 207 case Op_StoreNKlass:
208 208 was_store = true; // Memory op is a store op
209 209 // Stores will have their address in slot 2 (memory in slot 1).
210 210 // If the value being nul-checked is in another slot, it means we
211 211 // are storing the checked value, which does NOT check the value!
212 212 if( mach->in(2) != val ) continue;
213 213 break; // Found a memory op?
214 214 case Op_StrComp:
215 215 case Op_StrEquals:
216 216 case Op_StrIndexOf:
217 217 case Op_AryEq:
218 218 case Op_EncodeISOArray:
219 219 // Not a legit memory op for implicit null check regardless of
220 220 // embedded loads
221 221 continue;
222 222 default: // Also check for embedded loads
223 223 if( !mach->needs_anti_dependence_check() )
224 224 continue; // Not an memory op; skip it
225 225 if( must_clone[iop] ) {
226 226 // Do not move nodes which produce flags because
227 227 // RA will try to clone it to place near branch and
228 228 // it will cause recompilation, see clone_node().
229 229 continue;
230 230 }
231 231 {
232 232 // Check that value is used in memory address in
233 233 // instructions with embedded load (CmpP val1,(val2+off)).
234 234 Node* base;
235 235 Node* index;
236 236 const MachOper* oper = mach->memory_inputs(base, index);
237 237 if (oper == NULL || oper == (MachOper*)-1) {
238 238 continue; // Not an memory op; skip it
239 239 }
240 240 if (val == base ||
241 241 val == index && val->bottom_type()->isa_narrowoop()) {
242 242 break; // Found it
243 243 } else {
244 244 continue; // Skip it
245 245 }
246 246 }
247 247 break;
248 248 }
249 249
250 250 // On some OSes (AIX) the page at address 0 is only write protected.
251 251 // If so, only Store operations will trap.
252 252 // But a read accessing the base of a heap-based compressed heap will trap.
253 253 if (!was_store && needs_explicit_null_check_for_read(val)) {
254 254 continue;
255 255 }
256 256
257 257 // check if the offset is not too high for implicit exception
258 258 {
259 259 intptr_t offset = 0;
260 260 const TypePtr *adr_type = NULL; // Do not need this return value here
261 261 const Node* base = mach->get_base_and_disp(offset, adr_type);
262 262 if (base == NULL || base == NodeSentinel) {
263 263 // Narrow oop address doesn't have base, only index
264 264 if( val->bottom_type()->isa_narrowoop() &&
265 265 MacroAssembler::needs_explicit_null_check(offset) )
266 266 continue; // Give up if offset is beyond page size
267 267 // cannot reason about it; is probably not implicit null exception
268 268 } else {
269 269 const TypePtr* tptr;
270 270 if (UseCompressedOops && (Universe::narrow_oop_shift() == 0 ||
271 271 Universe::narrow_klass_shift() == 0)) {
272 272 // 32-bits narrow oop can be the base of address expressions
273 273 tptr = base->get_ptr_type();
274 274 } else {
275 275 // only regular oops are expected here
276 276 tptr = base->bottom_type()->is_ptr();
277 277 }
278 278 // Give up if offset is not a compile-time constant
279 279 if( offset == Type::OffsetBot || tptr->_offset == Type::OffsetBot )
280 280 continue;
281 281 offset += tptr->_offset; // correct if base is offseted
282 282 if( MacroAssembler::needs_explicit_null_check(offset) )
283 283 continue; // Give up is reference is beyond 4K page size
284 284 }
285 285 }
286 286
287 287 // Check ctrl input to see if the null-check dominates the memory op
288 288 Block *cb = get_block_for_node(mach);
289 289 cb = cb->_idom; // Always hoist at least 1 block
290 290 if( !was_store ) { // Stores can be hoisted only one block
291 291 while( cb->_dom_depth > (block->_dom_depth + 1))
292 292 cb = cb->_idom; // Hoist loads as far as we want
293 293 // The non-null-block should dominate the memory op, too. Live
294 294 // range spilling will insert a spill in the non-null-block if it is
295 295 // needs to spill the memory op for an implicit null check.
296 296 if (cb->_dom_depth == (block->_dom_depth + 1)) {
297 297 if (cb != not_null_block) continue;
298 298 cb = cb->_idom;
299 299 }
300 300 }
301 301 if( cb != block ) continue;
302 302
303 303 // Found a memory user; see if it can be hoisted to check-block
304 304 uint vidx = 0; // Capture index of value into memop
305 305 uint j;
306 306 for( j = mach->req()-1; j > 0; j-- ) {
307 307 if( mach->in(j) == val ) {
308 308 vidx = j;
309 309 // Ignore DecodeN val which could be hoisted to where needed.
310 310 if( is_decoden ) continue;
311 311 }
312 312 // Block of memory-op input
313 313 Block *inb = get_block_for_node(mach->in(j));
314 314 Block *b = block; // Start from nul check
315 315 while( b != inb && b->_dom_depth > inb->_dom_depth )
316 316 b = b->_idom; // search upwards for input
317 317 // See if input dominates null check
318 318 if( b != inb )
319 319 break;
320 320 }
321 321 if( j > 0 )
322 322 continue;
323 323 Block *mb = get_block_for_node(mach);
324 324 // Hoisting stores requires more checks for the anti-dependence case.
325 325 // Give up hoisting if we have to move the store past any load.
326 326 if( was_store ) {
327 327 Block *b = mb; // Start searching here for a local load
328 328 // mach use (faulting) trying to hoist
329 329 // n might be blocker to hoisting
330 330 while( b != block ) {
331 331 uint k;
332 332 for( k = 1; k < b->number_of_nodes(); k++ ) {
333 333 Node *n = b->get_node(k);
334 334 if( n->needs_anti_dependence_check() &&
335 335 n->in(LoadNode::Memory) == mach->in(StoreNode::Memory) )
336 336 break; // Found anti-dependent load
337 337 }
338 338 if( k < b->number_of_nodes() )
339 339 break; // Found anti-dependent load
340 340 // Make sure control does not do a merge (would have to check allpaths)
341 341 if( b->num_preds() != 2 ) break;
342 342 b = get_block_for_node(b->pred(1)); // Move up to predecessor block
343 343 }
344 344 if( b != block ) continue;
345 345 }
346 346
347 347 // Make sure this memory op is not already being used for a NullCheck
348 348 Node *e = mb->end();
349 349 if( e->is_MachNullCheck() && e->in(1) == mach )
350 350 continue; // Already being used as a NULL check
351 351
352 352 // Found a candidate! Pick one with least dom depth - the highest
353 353 // in the dom tree should be closest to the null check.
354 354 if (best == NULL || get_block_for_node(mach)->_dom_depth < get_block_for_node(best)->_dom_depth) {
355 355 best = mach;
356 356 bidx = vidx;
357 357 }
358 358 }
359 359 // No candidate!
360 360 if (best == NULL) {
361 361 return;
362 362 }
363 363
364 364 // ---- Found an implicit null check
365 365 extern int implicit_null_checks;
366 366 implicit_null_checks++;
367 367
368 368 if( is_decoden ) {
369 369 // Check if we need to hoist decodeHeapOop_not_null first.
370 370 Block *valb = get_block_for_node(val);
371 371 if( block != valb && block->_dom_depth < valb->_dom_depth ) {
372 372 // Hoist it up to the end of the test block.
373 373 valb->find_remove(val);
374 374 block->add_inst(val);
375 375 map_node_to_block(val, block);
376 376 // DecodeN on x86 may kill flags. Check for flag-killing projections
377 377 // that also need to be hoisted.
378 378 for (DUIterator_Fast jmax, j = val->fast_outs(jmax); j < jmax; j++) {
379 379 Node* n = val->fast_out(j);
380 380 if( n->is_MachProj() ) {
381 381 get_block_for_node(n)->find_remove(n);
382 382 block->add_inst(n);
383 383 map_node_to_block(n, block);
384 384 }
385 385 }
386 386 }
387 387 }
388 388 // Hoist the memory candidate up to the end of the test block.
389 389 Block *old_block = get_block_for_node(best);
390 390 old_block->find_remove(best);
391 391 block->add_inst(best);
392 392 map_node_to_block(best, block);
393 393
394 394 // Move the control dependence
395 395 if (best->in(0) && best->in(0) == old_block->head())
396 396 best->set_req(0, block->head());
397 397
398 398 // Check for flag-killing projections that also need to be hoisted
399 399 // Should be DU safe because no edge updates.
400 400 for (DUIterator_Fast jmax, j = best->fast_outs(jmax); j < jmax; j++) {
401 401 Node* n = best->fast_out(j);
402 402 if( n->is_MachProj() ) {
403 403 get_block_for_node(n)->find_remove(n);
404 404 block->add_inst(n);
405 405 map_node_to_block(n, block);
406 406 }
407 407 }
408 408
409 409 // proj==Op_True --> ne test; proj==Op_False --> eq test.
410 410 // One of two graph shapes got matched:
411 411 // (IfTrue (If (Bool NE (CmpP ptr NULL))))
412 412 // (IfFalse (If (Bool EQ (CmpP ptr NULL))))
413 413 // NULL checks are always branch-if-eq. If we see a IfTrue projection
414 414 // then we are replacing a 'ne' test with a 'eq' NULL check test.
415 415 // We need to flip the projections to keep the same semantics.
416 416 if( proj->Opcode() == Op_IfTrue ) {
417 417 // Swap order of projections in basic block to swap branch targets
418 418 Node *tmp1 = block->get_node(block->end_idx()+1);
419 419 Node *tmp2 = block->get_node(block->end_idx()+2);
420 420 block->map_node(tmp2, block->end_idx()+1);
421 421 block->map_node(tmp1, block->end_idx()+2);
422 422 Node *tmp = new (C) Node(C->top()); // Use not NULL input
423 423 tmp1->replace_by(tmp);
424 424 tmp2->replace_by(tmp1);
425 425 tmp->replace_by(tmp2);
426 426 tmp->destruct();
427 427 }
428 428
429 429 // Remove the existing null check; use a new implicit null check instead.
|
↓ open down ↓ |
429 lines elided |
↑ open up ↑ |
430 430 // Since schedule-local needs precise def-use info, we need to correct
431 431 // it as well.
432 432 Node *old_tst = proj->in(0);
433 433 MachNode *nul_chk = new (C) MachNullCheckNode(old_tst->in(0),best,bidx);
434 434 block->map_node(nul_chk, block->end_idx());
435 435 map_node_to_block(nul_chk, block);
436 436 // Redirect users of old_test to nul_chk
437 437 for (DUIterator_Last i2min, i2 = old_tst->last_outs(i2min); i2 >= i2min; --i2)
438 438 old_tst->last_out(i2)->set_req(0, nul_chk);
439 439 // Clean-up any dead code
440 - for (uint i3 = 0; i3 < old_tst->req(); i3++)
440 + for (uint i3 = 0; i3 < old_tst->req(); i3++) {
441 + Node* in = old_tst->in(i3);
441 442 old_tst->set_req(i3, NULL);
443 + if (in->outcnt() == 0) {
444 + // Remove dead input node
445 + in->disconnect_inputs(NULL, C);
446 + block->find_remove(in);
447 + }
448 + }
442 449
443 450 latency_from_uses(nul_chk);
444 451 latency_from_uses(best);
445 452 }
446 453
447 454
448 455 //------------------------------select-----------------------------------------
449 456 // Select a nice fellow from the worklist to schedule next. If there is only
450 457 // one choice, then use it. Projections take top priority for correctness
451 458 // reasons - if I see a projection, then it is next. There are a number of
452 459 // other special cases, for instructions that consume condition codes, et al.
453 460 // These are chosen immediately. Some instructions are required to immediately
454 461 // precede the last instruction in the block, and these are taken last. Of the
455 462 // remaining cases (most), choose the instruction with the greatest latency
456 463 // (that is, the most number of pseudo-cycles required to the end of the
457 464 // routine). If there is a tie, choose the instruction with the most inputs.
458 465 Node* PhaseCFG::select(Block* block, Node_List &worklist, GrowableArray<int> &ready_cnt, VectorSet &next_call, uint sched_slot) {
459 466
460 467 // If only a single entry on the stack, use it
461 468 uint cnt = worklist.size();
462 469 if (cnt == 1) {
463 470 Node *n = worklist[0];
464 471 worklist.map(0,worklist.pop());
465 472 return n;
466 473 }
467 474
468 475 uint choice = 0; // Bigger is most important
469 476 uint latency = 0; // Bigger is scheduled first
470 477 uint score = 0; // Bigger is better
471 478 int idx = -1; // Index in worklist
472 479 int cand_cnt = 0; // Candidate count
473 480
474 481 for( uint i=0; i<cnt; i++ ) { // Inspect entire worklist
475 482 // Order in worklist is used to break ties.
476 483 // See caller for how this is used to delay scheduling
477 484 // of induction variable increments to after the other
478 485 // uses of the phi are scheduled.
479 486 Node *n = worklist[i]; // Get Node on worklist
480 487
481 488 int iop = n->is_Mach() ? n->as_Mach()->ideal_Opcode() : 0;
482 489 if( n->is_Proj() || // Projections always win
483 490 n->Opcode()== Op_Con || // So does constant 'Top'
484 491 iop == Op_CreateEx || // Create-exception must start block
485 492 iop == Op_CheckCastPP
486 493 ) {
487 494 worklist.map(i,worklist.pop());
488 495 return n;
489 496 }
490 497
491 498 // Final call in a block must be adjacent to 'catch'
492 499 Node *e = block->end();
493 500 if( e->is_Catch() && e->in(0)->in(0) == n )
494 501 continue;
495 502
496 503 // Memory op for an implicit null check has to be at the end of the block
497 504 if( e->is_MachNullCheck() && e->in(1) == n )
498 505 continue;
499 506
500 507 // Schedule IV increment last.
501 508 if (e->is_Mach() && e->as_Mach()->ideal_Opcode() == Op_CountedLoopEnd &&
502 509 e->in(1)->in(1) == n && n->is_iteratively_computed())
503 510 continue;
504 511
505 512 uint n_choice = 2;
506 513
507 514 // See if this instruction is consumed by a branch. If so, then (as the
508 515 // branch is the last instruction in the basic block) force it to the
509 516 // end of the basic block
510 517 if ( must_clone[iop] ) {
511 518 // See if any use is a branch
512 519 bool found_machif = false;
513 520
514 521 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
515 522 Node* use = n->fast_out(j);
516 523
517 524 // The use is a conditional branch, make them adjacent
518 525 if (use->is_MachIf() && get_block_for_node(use) == block) {
519 526 found_machif = true;
520 527 break;
521 528 }
522 529
523 530 // More than this instruction pending for successor to be ready,
524 531 // don't choose this if other opportunities are ready
525 532 if (ready_cnt.at(use->_idx) > 1)
526 533 n_choice = 1;
527 534 }
528 535
529 536 // loop terminated, prefer not to use this instruction
530 537 if (found_machif)
531 538 continue;
532 539 }
533 540
534 541 // See if this has a predecessor that is "must_clone", i.e. sets the
535 542 // condition code. If so, choose this first
536 543 for (uint j = 0; j < n->req() ; j++) {
537 544 Node *inn = n->in(j);
538 545 if (inn) {
539 546 if (inn->is_Mach() && must_clone[inn->as_Mach()->ideal_Opcode()] ) {
540 547 n_choice = 3;
541 548 break;
542 549 }
543 550 }
544 551 }
545 552
546 553 // MachTemps should be scheduled last so they are near their uses
547 554 if (n->is_MachTemp()) {
548 555 n_choice = 1;
549 556 }
550 557
551 558 uint n_latency = get_latency_for_node(n);
552 559 uint n_score = n->req(); // Many inputs get high score to break ties
553 560
554 561 // Keep best latency found
555 562 cand_cnt++;
556 563 if (choice < n_choice ||
557 564 (choice == n_choice &&
558 565 ((StressLCM && Compile::randomized_select(cand_cnt)) ||
559 566 (!StressLCM &&
560 567 (latency < n_latency ||
561 568 (latency == n_latency &&
562 569 (score < n_score))))))) {
563 570 choice = n_choice;
564 571 latency = n_latency;
565 572 score = n_score;
566 573 idx = i; // Also keep index in worklist
567 574 }
568 575 } // End of for all ready nodes in worklist
569 576
570 577 assert(idx >= 0, "index should be set");
571 578 Node *n = worklist[(uint)idx]; // Get the winner
572 579
573 580 worklist.map((uint)idx, worklist.pop()); // Compress worklist
574 581 return n;
575 582 }
576 583
577 584
578 585 //------------------------------set_next_call----------------------------------
579 586 void PhaseCFG::set_next_call(Block* block, Node* n, VectorSet& next_call) {
580 587 if( next_call.test_set(n->_idx) ) return;
581 588 for( uint i=0; i<n->len(); i++ ) {
582 589 Node *m = n->in(i);
583 590 if( !m ) continue; // must see all nodes in block that precede call
584 591 if (get_block_for_node(m) == block) {
585 592 set_next_call(block, m, next_call);
586 593 }
587 594 }
588 595 }
589 596
590 597 //------------------------------needed_for_next_call---------------------------
591 598 // Set the flag 'next_call' for each Node that is needed for the next call to
592 599 // be scheduled. This flag lets me bias scheduling so Nodes needed for the
593 600 // next subroutine call get priority - basically it moves things NOT needed
594 601 // for the next call till after the call. This prevents me from trying to
595 602 // carry lots of stuff live across a call.
596 603 void PhaseCFG::needed_for_next_call(Block* block, Node* this_call, VectorSet& next_call) {
597 604 // Find the next control-defining Node in this block
598 605 Node* call = NULL;
599 606 for (DUIterator_Fast imax, i = this_call->fast_outs(imax); i < imax; i++) {
600 607 Node* m = this_call->fast_out(i);
601 608 if (get_block_for_node(m) == block && // Local-block user
602 609 m != this_call && // Not self-start node
603 610 m->is_MachCall()) {
604 611 call = m;
605 612 break;
606 613 }
607 614 }
608 615 if (call == NULL) return; // No next call (e.g., block end is near)
609 616 // Set next-call for all inputs to this call
610 617 set_next_call(block, call, next_call);
611 618 }
612 619
613 620 //------------------------------add_call_kills-------------------------------------
614 621 // helper function that adds caller save registers to MachProjNode
615 622 static void add_call_kills(MachProjNode *proj, RegMask& regs, const char* save_policy, bool exclude_soe) {
616 623 // Fill in the kill mask for the call
617 624 for( OptoReg::Name r = OptoReg::Name(0); r < _last_Mach_Reg; r=OptoReg::add(r,1) ) {
618 625 if( !regs.Member(r) ) { // Not already defined by the call
619 626 // Save-on-call register?
620 627 if ((save_policy[r] == 'C') ||
621 628 (save_policy[r] == 'A') ||
622 629 ((save_policy[r] == 'E') && exclude_soe)) {
623 630 proj->_rout.Insert(r);
624 631 }
625 632 }
626 633 }
627 634 }
628 635
629 636
630 637 //------------------------------sched_call-------------------------------------
631 638 uint PhaseCFG::sched_call(Block* block, uint node_cnt, Node_List& worklist, GrowableArray<int>& ready_cnt, MachCallNode* mcall, VectorSet& next_call) {
632 639 RegMask regs;
633 640
634 641 // Schedule all the users of the call right now. All the users are
635 642 // projection Nodes, so they must be scheduled next to the call.
636 643 // Collect all the defined registers.
637 644 for (DUIterator_Fast imax, i = mcall->fast_outs(imax); i < imax; i++) {
638 645 Node* n = mcall->fast_out(i);
639 646 assert( n->is_MachProj(), "" );
640 647 int n_cnt = ready_cnt.at(n->_idx)-1;
641 648 ready_cnt.at_put(n->_idx, n_cnt);
642 649 assert( n_cnt == 0, "" );
643 650 // Schedule next to call
644 651 block->map_node(n, node_cnt++);
645 652 // Collect defined registers
646 653 regs.OR(n->out_RegMask());
647 654 // Check for scheduling the next control-definer
648 655 if( n->bottom_type() == Type::CONTROL )
649 656 // Warm up next pile of heuristic bits
650 657 needed_for_next_call(block, n, next_call);
651 658
652 659 // Children of projections are now all ready
653 660 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
654 661 Node* m = n->fast_out(j); // Get user
655 662 if(get_block_for_node(m) != block) {
656 663 continue;
657 664 }
658 665 if( m->is_Phi() ) continue;
659 666 int m_cnt = ready_cnt.at(m->_idx)-1;
660 667 ready_cnt.at_put(m->_idx, m_cnt);
661 668 if( m_cnt == 0 )
662 669 worklist.push(m);
663 670 }
664 671
665 672 }
666 673
667 674 // Act as if the call defines the Frame Pointer.
668 675 // Certainly the FP is alive and well after the call.
669 676 regs.Insert(_matcher.c_frame_pointer());
670 677
671 678 // Set all registers killed and not already defined by the call.
672 679 uint r_cnt = mcall->tf()->range()->cnt();
673 680 int op = mcall->ideal_Opcode();
674 681 MachProjNode *proj = new (C) MachProjNode( mcall, r_cnt+1, RegMask::Empty, MachProjNode::fat_proj );
675 682 map_node_to_block(proj, block);
676 683 block->insert_node(proj, node_cnt++);
677 684
678 685 // Select the right register save policy.
679 686 const char * save_policy;
680 687 switch (op) {
681 688 case Op_CallRuntime:
682 689 case Op_CallLeaf:
683 690 case Op_CallLeafNoFP:
684 691 // Calling C code so use C calling convention
685 692 save_policy = _matcher._c_reg_save_policy;
686 693 break;
687 694
688 695 case Op_CallStaticJava:
689 696 case Op_CallDynamicJava:
690 697 // Calling Java code so use Java calling convention
691 698 save_policy = _matcher._register_save_policy;
692 699 break;
693 700
694 701 default:
695 702 ShouldNotReachHere();
696 703 }
697 704
698 705 // When using CallRuntime mark SOE registers as killed by the call
699 706 // so values that could show up in the RegisterMap aren't live in a
700 707 // callee saved register since the register wouldn't know where to
701 708 // find them. CallLeaf and CallLeafNoFP are ok because they can't
702 709 // have debug info on them. Strictly speaking this only needs to be
703 710 // done for oops since idealreg2debugmask takes care of debug info
704 711 // references but there no way to handle oops differently than other
705 712 // pointers as far as the kill mask goes.
706 713 bool exclude_soe = op == Op_CallRuntime;
707 714
708 715 // If the call is a MethodHandle invoke, we need to exclude the
709 716 // register which is used to save the SP value over MH invokes from
710 717 // the mask. Otherwise this register could be used for
711 718 // deoptimization information.
712 719 if (op == Op_CallStaticJava) {
713 720 MachCallStaticJavaNode* mcallstaticjava = (MachCallStaticJavaNode*) mcall;
714 721 if (mcallstaticjava->_method_handle_invoke)
715 722 proj->_rout.OR(Matcher::method_handle_invoke_SP_save_mask());
716 723 }
717 724
718 725 add_call_kills(proj, regs, save_policy, exclude_soe);
719 726
720 727 return node_cnt;
721 728 }
722 729
723 730
724 731 //------------------------------schedule_local---------------------------------
725 732 // Topological sort within a block. Someday become a real scheduler.
726 733 bool PhaseCFG::schedule_local(Block* block, GrowableArray<int>& ready_cnt, VectorSet& next_call) {
727 734 // Already "sorted" are the block start Node (as the first entry), and
728 735 // the block-ending Node and any trailing control projections. We leave
729 736 // these alone. PhiNodes and ParmNodes are made to follow the block start
730 737 // Node. Everything else gets topo-sorted.
731 738
732 739 #ifndef PRODUCT
733 740 if (trace_opto_pipelining()) {
734 741 tty->print_cr("# --- schedule_local B%d, before: ---", block->_pre_order);
735 742 for (uint i = 0;i < block->number_of_nodes(); i++) {
736 743 tty->print("# ");
737 744 block->get_node(i)->fast_dump();
738 745 }
739 746 tty->print_cr("#");
740 747 }
741 748 #endif
742 749
743 750 // RootNode is already sorted
744 751 if (block->number_of_nodes() == 1) {
745 752 return true;
746 753 }
747 754
748 755 // Move PhiNodes and ParmNodes from 1 to cnt up to the start
749 756 uint node_cnt = block->end_idx();
750 757 uint phi_cnt = 1;
751 758 uint i;
752 759 for( i = 1; i<node_cnt; i++ ) { // Scan for Phi
753 760 Node *n = block->get_node(i);
754 761 if( n->is_Phi() || // Found a PhiNode or ParmNode
755 762 (n->is_Proj() && n->in(0) == block->head()) ) {
756 763 // Move guy at 'phi_cnt' to the end; makes a hole at phi_cnt
757 764 block->map_node(block->get_node(phi_cnt), i);
758 765 block->map_node(n, phi_cnt++); // swap Phi/Parm up front
759 766 } else { // All others
760 767 // Count block-local inputs to 'n'
761 768 uint cnt = n->len(); // Input count
762 769 uint local = 0;
763 770 for( uint j=0; j<cnt; j++ ) {
764 771 Node *m = n->in(j);
765 772 if( m && get_block_for_node(m) == block && !m->is_top() )
766 773 local++; // One more block-local input
767 774 }
768 775 ready_cnt.at_put(n->_idx, local); // Count em up
769 776
770 777 #ifdef ASSERT
771 778 if( UseConcMarkSweepGC || UseG1GC ) {
772 779 if( n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_StoreCM ) {
773 780 // Check the precedence edges
774 781 for (uint prec = n->req(); prec < n->len(); prec++) {
775 782 Node* oop_store = n->in(prec);
776 783 if (oop_store != NULL) {
777 784 assert(get_block_for_node(oop_store)->_dom_depth <= block->_dom_depth, "oop_store must dominate card-mark");
778 785 }
779 786 }
780 787 }
781 788 }
782 789 #endif
783 790
784 791 // A few node types require changing a required edge to a precedence edge
785 792 // before allocation.
786 793 if( n->is_Mach() && n->req() > TypeFunc::Parms &&
787 794 (n->as_Mach()->ideal_Opcode() == Op_MemBarAcquire ||
788 795 n->as_Mach()->ideal_Opcode() == Op_MemBarVolatile) ) {
789 796 // MemBarAcquire could be created without Precedent edge.
790 797 // del_req() replaces the specified edge with the last input edge
791 798 // and then removes the last edge. If the specified edge > number of
792 799 // edges the last edge will be moved outside of the input edges array
793 800 // and the edge will be lost. This is why this code should be
794 801 // executed only when Precedent (== TypeFunc::Parms) edge is present.
795 802 Node *x = n->in(TypeFunc::Parms);
796 803 n->del_req(TypeFunc::Parms);
797 804 n->add_prec(x);
798 805 }
799 806 }
800 807 }
801 808 for(uint i2=i; i2< block->number_of_nodes(); i2++ ) // Trailing guys get zapped count
802 809 ready_cnt.at_put(block->get_node(i2)->_idx, 0);
803 810
804 811 // All the prescheduled guys do not hold back internal nodes
805 812 uint i3;
806 813 for(i3 = 0; i3<phi_cnt; i3++ ) { // For all pre-scheduled
807 814 Node *n = block->get_node(i3); // Get pre-scheduled
808 815 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
809 816 Node* m = n->fast_out(j);
810 817 if (get_block_for_node(m) == block) { // Local-block user
811 818 int m_cnt = ready_cnt.at(m->_idx)-1;
812 819 ready_cnt.at_put(m->_idx, m_cnt); // Fix ready count
813 820 }
814 821 }
815 822 }
816 823
817 824 Node_List delay;
818 825 // Make a worklist
819 826 Node_List worklist;
820 827 for(uint i4=i3; i4<node_cnt; i4++ ) { // Put ready guys on worklist
821 828 Node *m = block->get_node(i4);
822 829 if( !ready_cnt.at(m->_idx) ) { // Zero ready count?
823 830 if (m->is_iteratively_computed()) {
824 831 // Push induction variable increments last to allow other uses
825 832 // of the phi to be scheduled first. The select() method breaks
826 833 // ties in scheduling by worklist order.
827 834 delay.push(m);
828 835 } else if (m->is_Mach() && m->as_Mach()->ideal_Opcode() == Op_CreateEx) {
829 836 // Force the CreateEx to the top of the list so it's processed
830 837 // first and ends up at the start of the block.
831 838 worklist.insert(0, m);
832 839 } else {
833 840 worklist.push(m); // Then on to worklist!
834 841 }
835 842 }
836 843 }
837 844 while (delay.size()) {
838 845 Node* d = delay.pop();
839 846 worklist.push(d);
840 847 }
841 848
842 849 // Warm up the 'next_call' heuristic bits
843 850 needed_for_next_call(block, block->head(), next_call);
844 851
845 852 #ifndef PRODUCT
846 853 if (trace_opto_pipelining()) {
847 854 for (uint j=0; j< block->number_of_nodes(); j++) {
848 855 Node *n = block->get_node(j);
849 856 int idx = n->_idx;
850 857 tty->print("# ready cnt:%3d ", ready_cnt.at(idx));
851 858 tty->print("latency:%3d ", get_latency_for_node(n));
852 859 tty->print("%4d: %s\n", idx, n->Name());
853 860 }
854 861 }
855 862 #endif
856 863
857 864 uint max_idx = (uint)ready_cnt.length();
858 865 // Pull from worklist and schedule
859 866 while( worklist.size() ) { // Worklist is not ready
860 867
861 868 #ifndef PRODUCT
862 869 if (trace_opto_pipelining()) {
863 870 tty->print("# ready list:");
864 871 for( uint i=0; i<worklist.size(); i++ ) { // Inspect entire worklist
865 872 Node *n = worklist[i]; // Get Node on worklist
866 873 tty->print(" %d", n->_idx);
867 874 }
868 875 tty->cr();
869 876 }
870 877 #endif
871 878
872 879 // Select and pop a ready guy from worklist
873 880 Node* n = select(block, worklist, ready_cnt, next_call, phi_cnt);
874 881 block->map_node(n, phi_cnt++); // Schedule him next
875 882
876 883 #ifndef PRODUCT
877 884 if (trace_opto_pipelining()) {
878 885 tty->print("# select %d: %s", n->_idx, n->Name());
879 886 tty->print(", latency:%d", get_latency_for_node(n));
880 887 n->dump();
881 888 if (Verbose) {
882 889 tty->print("# ready list:");
883 890 for( uint i=0; i<worklist.size(); i++ ) { // Inspect entire worklist
884 891 Node *n = worklist[i]; // Get Node on worklist
885 892 tty->print(" %d", n->_idx);
886 893 }
887 894 tty->cr();
888 895 }
889 896 }
890 897
891 898 #endif
892 899 if( n->is_MachCall() ) {
893 900 MachCallNode *mcall = n->as_MachCall();
894 901 phi_cnt = sched_call(block, phi_cnt, worklist, ready_cnt, mcall, next_call);
895 902 continue;
896 903 }
897 904
898 905 if (n->is_Mach() && n->as_Mach()->has_call()) {
899 906 RegMask regs;
900 907 regs.Insert(_matcher.c_frame_pointer());
901 908 regs.OR(n->out_RegMask());
902 909
903 910 MachProjNode *proj = new (C) MachProjNode( n, 1, RegMask::Empty, MachProjNode::fat_proj );
904 911 map_node_to_block(proj, block);
905 912 block->insert_node(proj, phi_cnt++);
906 913
907 914 add_call_kills(proj, regs, _matcher._c_reg_save_policy, false);
908 915 }
909 916
910 917 // Children are now all ready
911 918 for (DUIterator_Fast i5max, i5 = n->fast_outs(i5max); i5 < i5max; i5++) {
912 919 Node* m = n->fast_out(i5); // Get user
913 920 if (get_block_for_node(m) != block) {
914 921 continue;
915 922 }
916 923 if( m->is_Phi() ) continue;
917 924 if (m->_idx >= max_idx) { // new node, skip it
918 925 assert(m->is_MachProj() && n->is_Mach() && n->as_Mach()->has_call(), "unexpected node types");
919 926 continue;
920 927 }
921 928 int m_cnt = ready_cnt.at(m->_idx)-1;
922 929 ready_cnt.at_put(m->_idx, m_cnt);
923 930 if( m_cnt == 0 )
924 931 worklist.push(m);
925 932 }
926 933 }
927 934
928 935 if( phi_cnt != block->end_idx() ) {
929 936 // did not schedule all. Retry, Bailout, or Die
930 937 if (C->subsume_loads() == true && !C->failing()) {
931 938 // Retry with subsume_loads == false
932 939 // If this is the first failure, the sentinel string will "stick"
933 940 // to the Compile object, and the C2Compiler will see it and retry.
934 941 C->record_failure(C2Compiler::retry_no_subsuming_loads());
935 942 }
936 943 // assert( phi_cnt == end_idx(), "did not schedule all" );
937 944 return false;
938 945 }
939 946
940 947 #ifndef PRODUCT
941 948 if (trace_opto_pipelining()) {
942 949 tty->print_cr("#");
943 950 tty->print_cr("# after schedule_local");
944 951 for (uint i = 0;i < block->number_of_nodes();i++) {
945 952 tty->print("# ");
946 953 block->get_node(i)->fast_dump();
947 954 }
948 955 tty->cr();
949 956 }
950 957 #endif
951 958
952 959
953 960 return true;
954 961 }
955 962
956 963 //--------------------------catch_cleanup_fix_all_inputs-----------------------
957 964 static void catch_cleanup_fix_all_inputs(Node *use, Node *old_def, Node *new_def) {
958 965 for (uint l = 0; l < use->len(); l++) {
959 966 if (use->in(l) == old_def) {
960 967 if (l < use->req()) {
961 968 use->set_req(l, new_def);
962 969 } else {
963 970 use->rm_prec(l);
964 971 use->add_prec(new_def);
965 972 l--;
966 973 }
967 974 }
968 975 }
969 976 }
970 977
971 978 //------------------------------catch_cleanup_find_cloned_def------------------
972 979 Node* PhaseCFG::catch_cleanup_find_cloned_def(Block *use_blk, Node *def, Block *def_blk, int n_clone_idx) {
973 980 assert( use_blk != def_blk, "Inter-block cleanup only");
974 981
975 982 // The use is some block below the Catch. Find and return the clone of the def
976 983 // that dominates the use. If there is no clone in a dominating block, then
977 984 // create a phi for the def in a dominating block.
978 985
979 986 // Find which successor block dominates this use. The successor
980 987 // blocks must all be single-entry (from the Catch only; I will have
981 988 // split blocks to make this so), hence they all dominate.
982 989 while( use_blk->_dom_depth > def_blk->_dom_depth+1 )
983 990 use_blk = use_blk->_idom;
984 991
985 992 // Find the successor
986 993 Node *fixup = NULL;
987 994
988 995 uint j;
989 996 for( j = 0; j < def_blk->_num_succs; j++ )
990 997 if( use_blk == def_blk->_succs[j] )
991 998 break;
992 999
993 1000 if( j == def_blk->_num_succs ) {
994 1001 // Block at same level in dom-tree is not a successor. It needs a
995 1002 // PhiNode, the PhiNode uses from the def and IT's uses need fixup.
996 1003 Node_Array inputs = new Node_List(Thread::current()->resource_area());
997 1004 for(uint k = 1; k < use_blk->num_preds(); k++) {
998 1005 Block* block = get_block_for_node(use_blk->pred(k));
999 1006 inputs.map(k, catch_cleanup_find_cloned_def(block, def, def_blk, n_clone_idx));
1000 1007 }
1001 1008
1002 1009 // Check to see if the use_blk already has an identical phi inserted.
1003 1010 // If it exists, it will be at the first position since all uses of a
1004 1011 // def are processed together.
1005 1012 Node *phi = use_blk->get_node(1);
1006 1013 if( phi->is_Phi() ) {
1007 1014 fixup = phi;
1008 1015 for (uint k = 1; k < use_blk->num_preds(); k++) {
1009 1016 if (phi->in(k) != inputs[k]) {
1010 1017 // Not a match
1011 1018 fixup = NULL;
1012 1019 break;
1013 1020 }
1014 1021 }
1015 1022 }
1016 1023
1017 1024 // If an existing PhiNode was not found, make a new one.
1018 1025 if (fixup == NULL) {
1019 1026 Node *new_phi = PhiNode::make(use_blk->head(), def);
1020 1027 use_blk->insert_node(new_phi, 1);
1021 1028 map_node_to_block(new_phi, use_blk);
1022 1029 for (uint k = 1; k < use_blk->num_preds(); k++) {
1023 1030 new_phi->set_req(k, inputs[k]);
1024 1031 }
1025 1032 fixup = new_phi;
1026 1033 }
1027 1034
1028 1035 } else {
1029 1036 // Found the use just below the Catch. Make it use the clone.
1030 1037 fixup = use_blk->get_node(n_clone_idx);
1031 1038 }
1032 1039
1033 1040 return fixup;
1034 1041 }
1035 1042
1036 1043 //--------------------------catch_cleanup_intra_block--------------------------
1037 1044 // Fix all input edges in use that reference "def". The use is in the same
1038 1045 // block as the def and both have been cloned in each successor block.
1039 1046 static void catch_cleanup_intra_block(Node *use, Node *def, Block *blk, int beg, int n_clone_idx) {
1040 1047
1041 1048 // Both the use and def have been cloned. For each successor block,
1042 1049 // get the clone of the use, and make its input the clone of the def
1043 1050 // found in that block.
1044 1051
1045 1052 uint use_idx = blk->find_node(use);
1046 1053 uint offset_idx = use_idx - beg;
1047 1054 for( uint k = 0; k < blk->_num_succs; k++ ) {
1048 1055 // Get clone in each successor block
1049 1056 Block *sb = blk->_succs[k];
1050 1057 Node *clone = sb->get_node(offset_idx+1);
1051 1058 assert( clone->Opcode() == use->Opcode(), "" );
1052 1059
1053 1060 // Make use-clone reference the def-clone
1054 1061 catch_cleanup_fix_all_inputs(clone, def, sb->get_node(n_clone_idx));
1055 1062 }
1056 1063 }
1057 1064
1058 1065 //------------------------------catch_cleanup_inter_block---------------------
1059 1066 // Fix all input edges in use that reference "def". The use is in a different
1060 1067 // block than the def.
1061 1068 void PhaseCFG::catch_cleanup_inter_block(Node *use, Block *use_blk, Node *def, Block *def_blk, int n_clone_idx) {
1062 1069 if( !use_blk ) return; // Can happen if the use is a precedence edge
1063 1070
1064 1071 Node *new_def = catch_cleanup_find_cloned_def(use_blk, def, def_blk, n_clone_idx);
1065 1072 catch_cleanup_fix_all_inputs(use, def, new_def);
1066 1073 }
1067 1074
1068 1075 //------------------------------call_catch_cleanup-----------------------------
1069 1076 // If we inserted any instructions between a Call and his CatchNode,
1070 1077 // clone the instructions on all paths below the Catch.
1071 1078 void PhaseCFG::call_catch_cleanup(Block* block) {
1072 1079
1073 1080 // End of region to clone
1074 1081 uint end = block->end_idx();
1075 1082 if( !block->get_node(end)->is_Catch() ) return;
1076 1083 // Start of region to clone
1077 1084 uint beg = end;
1078 1085 while(!block->get_node(beg-1)->is_MachProj() ||
1079 1086 !block->get_node(beg-1)->in(0)->is_MachCall() ) {
1080 1087 beg--;
1081 1088 assert(beg > 0,"Catch cleanup walking beyond block boundary");
1082 1089 }
1083 1090 // Range of inserted instructions is [beg, end)
1084 1091 if( beg == end ) return;
1085 1092
1086 1093 // Clone along all Catch output paths. Clone area between the 'beg' and
1087 1094 // 'end' indices.
1088 1095 for( uint i = 0; i < block->_num_succs; i++ ) {
1089 1096 Block *sb = block->_succs[i];
1090 1097 // Clone the entire area; ignoring the edge fixup for now.
1091 1098 for( uint j = end; j > beg; j-- ) {
1092 1099 // It is safe here to clone a node with anti_dependence
1093 1100 // since clones dominate on each path.
1094 1101 Node *clone = block->get_node(j-1)->clone();
1095 1102 sb->insert_node(clone, 1);
1096 1103 map_node_to_block(clone, sb);
1097 1104 }
1098 1105 }
1099 1106
1100 1107
1101 1108 // Fixup edges. Check the def-use info per cloned Node
1102 1109 for(uint i2 = beg; i2 < end; i2++ ) {
1103 1110 uint n_clone_idx = i2-beg+1; // Index of clone of n in each successor block
1104 1111 Node *n = block->get_node(i2); // Node that got cloned
1105 1112 // Need DU safe iterator because of edge manipulation in calls.
1106 1113 Unique_Node_List *out = new Unique_Node_List(Thread::current()->resource_area());
1107 1114 for (DUIterator_Fast j1max, j1 = n->fast_outs(j1max); j1 < j1max; j1++) {
1108 1115 out->push(n->fast_out(j1));
1109 1116 }
1110 1117 uint max = out->size();
1111 1118 for (uint j = 0; j < max; j++) {// For all users
1112 1119 Node *use = out->pop();
1113 1120 Block *buse = get_block_for_node(use);
1114 1121 if( use->is_Phi() ) {
1115 1122 for( uint k = 1; k < use->req(); k++ )
1116 1123 if( use->in(k) == n ) {
1117 1124 Block* b = get_block_for_node(buse->pred(k));
1118 1125 Node *fixup = catch_cleanup_find_cloned_def(b, n, block, n_clone_idx);
1119 1126 use->set_req(k, fixup);
1120 1127 }
1121 1128 } else {
1122 1129 if (block == buse) {
1123 1130 catch_cleanup_intra_block(use, n, block, beg, n_clone_idx);
1124 1131 } else {
1125 1132 catch_cleanup_inter_block(use, buse, n, block, n_clone_idx);
1126 1133 }
1127 1134 }
1128 1135 } // End for all users
1129 1136
1130 1137 } // End of for all Nodes in cloned area
1131 1138
1132 1139 // Remove the now-dead cloned ops
1133 1140 for(uint i3 = beg; i3 < end; i3++ ) {
1134 1141 block->get_node(beg)->disconnect_inputs(NULL, C);
1135 1142 block->remove_node(beg);
1136 1143 }
1137 1144
1138 1145 // If the successor blocks have a CreateEx node, move it back to the top
1139 1146 for(uint i4 = 0; i4 < block->_num_succs; i4++ ) {
1140 1147 Block *sb = block->_succs[i4];
1141 1148 uint new_cnt = end - beg;
1142 1149 // Remove any newly created, but dead, nodes.
1143 1150 for( uint j = new_cnt; j > 0; j-- ) {
1144 1151 Node *n = sb->get_node(j);
1145 1152 if (n->outcnt() == 0 &&
1146 1153 (!n->is_Proj() || n->as_Proj()->in(0)->outcnt() == 1) ){
1147 1154 n->disconnect_inputs(NULL, C);
1148 1155 sb->remove_node(j);
1149 1156 new_cnt--;
1150 1157 }
1151 1158 }
1152 1159 // If any newly created nodes remain, move the CreateEx node to the top
1153 1160 if (new_cnt > 0) {
1154 1161 Node *cex = sb->get_node(1+new_cnt);
1155 1162 if( cex->is_Mach() && cex->as_Mach()->ideal_Opcode() == Op_CreateEx ) {
1156 1163 sb->remove_node(1+new_cnt);
1157 1164 sb->insert_node(cex, 1);
1158 1165 }
1159 1166 }
1160 1167 }
1161 1168 }
|
↓ open down ↓ |
710 lines elided |
↑ open up ↑ |
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX