1 /*
2 * Copyright (c) 2015, 2019, Red Hat, Inc. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26
27 #include "gc/shenandoah/c2/shenandoahSupport.hpp"
28 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
29 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp"
30 #include "gc/shenandoah/shenandoahForwarding.hpp"
31 #include "gc/shenandoah/shenandoahHeap.hpp"
32 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
33 #include "gc/shenandoah/shenandoahRuntime.hpp"
34 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
35 #include "opto/arraycopynode.hpp"
36 #include "opto/block.hpp"
37 #include "opto/callnode.hpp"
38 #include "opto/castnode.hpp"
39 #include "opto/movenode.hpp"
40 #include "opto/phaseX.hpp"
41 #include "opto/rootnode.hpp"
42 #include "opto/runtime.hpp"
43 #include "opto/subnode.hpp"
44
45 bool ShenandoahBarrierC2Support::expand(Compile* C, PhaseIterGVN& igvn) {
46 ShenandoahBarrierSetC2State* state = ShenandoahBarrierSetC2::bsc2()->state();
47 if ((state->enqueue_barriers_count() +
48 state->load_reference_barriers_count()) > 0) {
49 bool attempt_more_loopopts = ShenandoahLoopOptsAfterExpansion;
50 C->clear_major_progress();
51 PhaseIdealLoop ideal_loop(igvn, LoopOptsShenandoahExpand);
52 if (C->failing()) return false;
53 PhaseIdealLoop::verify(igvn);
54 DEBUG_ONLY(verify_raw_mem(C->root());)
55 if (attempt_more_loopopts) {
56 C->set_major_progress();
57 if (!C->optimize_loops(igvn, LoopOptsShenandoahPostExpand)) {
58 return false;
59 }
60 C->clear_major_progress();
61 if (C->range_check_cast_count() > 0) {
62 // No more loop optimizations. Remove all range check dependent CastIINodes.
63 C->remove_range_check_casts(igvn);
64 igvn.optimize();
65 }
66 }
67 }
68 return true;
69 }
70
71 bool ShenandoahBarrierC2Support::is_gc_state_test(Node* iff, int mask) {
72 if (!UseShenandoahGC) {
73 return false;
74 }
75 assert(iff->is_If(), "bad input");
76 if (iff->Opcode() != Op_If) {
77 return false;
78 }
79 Node* bol = iff->in(1);
80 if (!bol->is_Bool() || bol->as_Bool()->_test._test != BoolTest::ne) {
81 return false;
82 }
83 Node* cmp = bol->in(1);
84 if (cmp->Opcode() != Op_CmpI) {
85 return false;
86 }
87 Node* in1 = cmp->in(1);
88 Node* in2 = cmp->in(2);
89 if (in2->find_int_con(-1) != 0) {
90 return false;
91 }
92 if (in1->Opcode() != Op_AndI) {
93 return false;
94 }
95 in2 = in1->in(2);
96 if (in2->find_int_con(-1) != mask) {
97 return false;
98 }
99 in1 = in1->in(1);
100
101 return is_gc_state_load(in1);
102 }
103
104 bool ShenandoahBarrierC2Support::is_heap_stable_test(Node* iff) {
105 return is_gc_state_test(iff, ShenandoahHeap::HAS_FORWARDED);
106 }
107
108 bool ShenandoahBarrierC2Support::is_gc_state_load(Node *n) {
109 if (!UseShenandoahGC) {
110 return false;
111 }
112 if (n->Opcode() != Op_LoadB && n->Opcode() != Op_LoadUB) {
113 return false;
114 }
115 Node* addp = n->in(MemNode::Address);
116 if (!addp->is_AddP()) {
117 return false;
118 }
119 Node* base = addp->in(AddPNode::Address);
120 Node* off = addp->in(AddPNode::Offset);
121 if (base->Opcode() != Op_ThreadLocal) {
122 return false;
123 }
124 if (off->find_intptr_t_con(-1) != in_bytes(ShenandoahThreadLocalData::gc_state_offset())) {
125 return false;
126 }
127 return true;
128 }
129
130 bool ShenandoahBarrierC2Support::has_safepoint_between(Node* start, Node* stop, PhaseIdealLoop *phase) {
131 assert(phase->is_dominator(stop, start), "bad inputs");
132 ResourceMark rm;
133 Unique_Node_List wq;
134 wq.push(start);
135 for (uint next = 0; next < wq.size(); next++) {
136 Node *m = wq.at(next);
137 if (m == stop) {
138 continue;
139 }
140 if (m->is_SafePoint() && !m->is_CallLeaf()) {
141 return true;
142 }
143 if (m->is_Region()) {
144 for (uint i = 1; i < m->req(); i++) {
145 wq.push(m->in(i));
146 }
147 } else {
148 wq.push(m->in(0));
149 }
150 }
151 return false;
152 }
153
154 #ifdef ASSERT
155 bool ShenandoahBarrierC2Support::verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used) {
156 assert(phis.size() == 0, "");
157
158 while (true) {
159 if (in->bottom_type() == TypePtr::NULL_PTR) {
160 if (trace) {tty->print_cr("NULL");}
161 } else if (!in->bottom_type()->make_ptr()->make_oopptr()) {
162 if (trace) {tty->print_cr("Non oop");}
163 } else {
164 if (in->is_ConstraintCast()) {
165 in = in->in(1);
166 continue;
167 } else if (in->is_AddP()) {
168 assert(!in->in(AddPNode::Address)->is_top(), "no raw memory access");
169 in = in->in(AddPNode::Address);
170 continue;
171 } else if (in->is_Con()) {
172 if (trace) {
173 tty->print("Found constant");
174 in->dump();
175 }
176 } else if (in->Opcode() == Op_Parm) {
177 if (trace) {
178 tty->print("Found argument");
179 }
180 } else if (in->Opcode() == Op_CreateEx) {
181 if (trace) {
182 tty->print("Found create-exception");
183 }
184 } else if (in->Opcode() == Op_LoadP && in->adr_type() == TypeRawPtr::BOTTOM) {
185 if (trace) {
186 tty->print("Found raw LoadP (OSR argument?)");
187 }
188 } else if (in->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
189 if (t == ShenandoahOopStore) {
190 uint i = 0;
191 for (; i < phis.size(); i++) {
192 Node* n = phis.node_at(i);
193 if (n->Opcode() == Op_ShenandoahEnqueueBarrier) {
194 break;
195 }
196 }
197 if (i == phis.size()) {
198 return false;
199 }
200 }
201 barriers_used.push(in);
202 if (trace) {tty->print("Found barrier"); in->dump();}
203 } else if (in->Opcode() == Op_ShenandoahEnqueueBarrier) {
204 if (t != ShenandoahOopStore) {
205 in = in->in(1);
206 continue;
207 }
208 if (trace) {tty->print("Found enqueue barrier"); in->dump();}
209 phis.push(in, in->req());
210 in = in->in(1);
211 continue;
212 } else if (in->is_Proj() && in->in(0)->is_Allocate()) {
213 if (trace) {
214 tty->print("Found alloc");
215 in->in(0)->dump();
216 }
217 } else if (in->is_Proj() && (in->in(0)->Opcode() == Op_CallStaticJava || in->in(0)->Opcode() == Op_CallDynamicJava)) {
218 if (trace) {
219 tty->print("Found Java call");
220 }
221 } else if (in->is_Phi()) {
222 if (!visited.test_set(in->_idx)) {
223 if (trace) {tty->print("Pushed phi:"); in->dump();}
224 phis.push(in, 2);
225 in = in->in(1);
226 continue;
227 }
228 if (trace) {tty->print("Already seen phi:"); in->dump();}
229 } else if (in->Opcode() == Op_CMoveP || in->Opcode() == Op_CMoveN) {
230 if (!visited.test_set(in->_idx)) {
231 if (trace) {tty->print("Pushed cmovep:"); in->dump();}
232 phis.push(in, CMoveNode::IfTrue);
233 in = in->in(CMoveNode::IfFalse);
234 continue;
235 }
236 if (trace) {tty->print("Already seen cmovep:"); in->dump();}
237 } else if (in->Opcode() == Op_EncodeP || in->Opcode() == Op_DecodeN) {
238 in = in->in(1);
239 continue;
240 } else {
241 return false;
242 }
243 }
244 bool cont = false;
245 while (phis.is_nonempty()) {
246 uint idx = phis.index();
247 Node* phi = phis.node();
248 if (idx >= phi->req()) {
249 if (trace) {tty->print("Popped phi:"); phi->dump();}
250 phis.pop();
251 continue;
252 }
253 if (trace) {tty->print("Next entry(%d) for phi:", idx); phi->dump();}
254 in = phi->in(idx);
255 phis.set_index(idx+1);
256 cont = true;
257 break;
258 }
259 if (!cont) {
260 break;
261 }
262 }
263 return true;
264 }
265
266 void ShenandoahBarrierC2Support::report_verify_failure(const char* msg, Node* n1, Node* n2) {
267 if (n1 != NULL) {
268 n1->dump(+10);
269 }
270 if (n2 != NULL) {
271 n2->dump(+10);
272 }
273 fatal("%s", msg);
274 }
275
276 void ShenandoahBarrierC2Support::verify(RootNode* root) {
277 ResourceMark rm;
278 Unique_Node_List wq;
279 GrowableArray<Node*> barriers;
280 Unique_Node_List barriers_used;
281 Node_Stack phis(0);
282 VectorSet visited(Thread::current()->resource_area());
283 const bool trace = false;
284 const bool verify_no_useless_barrier = false;
285
286 wq.push(root);
287 for (uint next = 0; next < wq.size(); next++) {
288 Node *n = wq.at(next);
289 if (n->is_Load()) {
290 const bool trace = false;
291 if (trace) {tty->print("Verifying"); n->dump();}
292 if (n->Opcode() == Op_LoadRange || n->Opcode() == Op_LoadKlass || n->Opcode() == Op_LoadNKlass) {
293 if (trace) {tty->print_cr("Load range/klass");}
294 } else {
295 const TypePtr* adr_type = n->as_Load()->adr_type();
296
297 if (adr_type->isa_oopptr() && adr_type->is_oopptr()->offset() == oopDesc::mark_offset_in_bytes()) {
298 if (trace) {tty->print_cr("Mark load");}
299 } else if (adr_type->isa_instptr() &&
300 adr_type->is_instptr()->klass()->is_subtype_of(Compile::current()->env()->Reference_klass()) &&
301 adr_type->is_instptr()->offset() == java_lang_ref_Reference::referent_offset) {
302 if (trace) {tty->print_cr("Reference.get()");}
303 } else if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahLoad, trace, barriers_used)) {
304 report_verify_failure("Shenandoah verification: Load should have barriers", n);
305 }
306 }
307 } else if (n->is_Store()) {
308 const bool trace = false;
309
310 if (trace) {tty->print("Verifying"); n->dump();}
311 if (n->in(MemNode::ValueIn)->bottom_type()->make_oopptr()) {
312 Node* adr = n->in(MemNode::Address);
313 bool verify = true;
314
315 if (adr->is_AddP() && adr->in(AddPNode::Base)->is_top()) {
316 adr = adr->in(AddPNode::Address);
317 if (adr->is_AddP()) {
318 assert(adr->in(AddPNode::Base)->is_top(), "");
319 adr = adr->in(AddPNode::Address);
320 if (adr->Opcode() == Op_LoadP &&
321 adr->in(MemNode::Address)->in(AddPNode::Base)->is_top() &&
322 adr->in(MemNode::Address)->in(AddPNode::Address)->Opcode() == Op_ThreadLocal &&
323 adr->in(MemNode::Address)->in(AddPNode::Offset)->find_intptr_t_con(-1) == in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset())) {
324 if (trace) {tty->print_cr("SATB prebarrier");}
325 verify = false;
326 }
327 }
328 }
329
330 if (verify && !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahStoreValEnqueueBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
331 report_verify_failure("Shenandoah verification: Store should have barriers", n);
332 }
333 }
334 if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
335 report_verify_failure("Shenandoah verification: Store (address) should have barriers", n);
336 }
337 } else if (n->Opcode() == Op_CmpP) {
338 const bool trace = false;
339
340 Node* in1 = n->in(1);
341 Node* in2 = n->in(2);
342 if (in1->bottom_type()->isa_oopptr()) {
343 if (trace) {tty->print("Verifying"); n->dump();}
344
345 bool mark_inputs = false;
346 if (in1->bottom_type() == TypePtr::NULL_PTR || in2->bottom_type() == TypePtr::NULL_PTR ||
347 (in1->is_Con() || in2->is_Con())) {
348 if (trace) {tty->print_cr("Comparison against a constant");}
349 mark_inputs = true;
350 } else if ((in1->is_CheckCastPP() && in1->in(1)->is_Proj() && in1->in(1)->in(0)->is_Allocate()) ||
351 (in2->is_CheckCastPP() && in2->in(1)->is_Proj() && in2->in(1)->in(0)->is_Allocate())) {
352 if (trace) {tty->print_cr("Comparison with newly alloc'ed object");}
353 mark_inputs = true;
354 } else {
355 assert(in2->bottom_type()->isa_oopptr(), "");
356
357 if (!verify_helper(in1, phis, visited, ShenandoahStore, trace, barriers_used) ||
358 !verify_helper(in2, phis, visited, ShenandoahStore, trace, barriers_used)) {
359 report_verify_failure("Shenandoah verification: Cmp should have barriers", n);
360 }
361 }
362 if (verify_no_useless_barrier &&
363 mark_inputs &&
364 (!verify_helper(in1, phis, visited, ShenandoahValue, trace, barriers_used) ||
365 !verify_helper(in2, phis, visited, ShenandoahValue, trace, barriers_used))) {
366 phis.clear();
367 visited.reset();
368 }
369 }
370 } else if (n->is_LoadStore()) {
371 if (n->in(MemNode::ValueIn)->bottom_type()->make_ptr() &&
372 !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahStoreValEnqueueBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
373 report_verify_failure("Shenandoah verification: LoadStore (value) should have barriers", n);
374 }
375
376 if (n->in(MemNode::Address)->bottom_type()->make_oopptr() && !verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
377 report_verify_failure("Shenandoah verification: LoadStore (address) should have barriers", n);
378 }
379 } else if (n->Opcode() == Op_CallLeafNoFP || n->Opcode() == Op_CallLeaf) {
380 CallNode* call = n->as_Call();
381
382 static struct {
383 const char* name;
384 struct {
385 int pos;
386 verify_type t;
387 } args[6];
388 } calls[] = {
389 "aescrypt_encryptBlock",
390 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
391 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
392 "aescrypt_decryptBlock",
393 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
394 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
395 "multiplyToLen",
396 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { TypeFunc::Parms+4, ShenandoahStore },
397 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
398 "squareToLen",
399 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { -1, ShenandoahNone},
400 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
401 "montgomery_multiply",
402 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
403 { TypeFunc::Parms+6, ShenandoahStore }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
404 "montgomery_square",
405 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+5, ShenandoahStore },
406 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
407 "mulAdd",
408 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
409 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
410 "vectorizedMismatch",
411 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
412 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
413 "updateBytesCRC32",
414 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
415 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
416 "updateBytesAdler32",
417 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
418 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
419 "updateBytesCRC32C",
420 { { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahLoad}, { -1, ShenandoahNone},
421 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
422 "counterMode_AESCrypt",
423 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
424 { TypeFunc::Parms+3, ShenandoahStore }, { TypeFunc::Parms+5, ShenandoahStore }, { TypeFunc::Parms+6, ShenandoahStore } },
425 "cipherBlockChaining_encryptAESCrypt",
426 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
427 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
428 "cipherBlockChaining_decryptAESCrypt",
429 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
430 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
431 "shenandoah_clone_barrier",
432 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
433 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
434 "ghash_processBlocks",
435 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
436 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
437 "sha1_implCompress",
438 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
439 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
440 "sha256_implCompress",
441 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
442 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
443 "sha512_implCompress",
444 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
445 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
446 "sha1_implCompressMB",
447 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
448 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
449 "sha256_implCompressMB",
450 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
451 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
452 "sha512_implCompressMB",
453 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
454 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
455 "encodeBlock",
456 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
457 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
458 };
459
460 if (call->is_call_to_arraycopystub()) {
461 Node* dest = NULL;
462 const TypeTuple* args = n->as_Call()->_tf->domain();
463 for (uint i = TypeFunc::Parms, j = 0; i < args->cnt(); i++) {
464 if (args->field_at(i)->isa_ptr()) {
465 j++;
466 if (j == 2) {
467 dest = n->in(i);
468 break;
469 }
470 }
471 }
472 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahLoad, trace, barriers_used) ||
473 !verify_helper(dest, phis, visited, ShenandoahStore, trace, barriers_used)) {
474 report_verify_failure("Shenandoah verification: ArrayCopy should have barriers", n);
475 }
476 } else if (strlen(call->_name) > 5 &&
477 !strcmp(call->_name + strlen(call->_name) - 5, "_fill")) {
478 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahStore, trace, barriers_used)) {
479 report_verify_failure("Shenandoah verification: _fill should have barriers", n);
480 }
481 } else if (!strcmp(call->_name, "shenandoah_wb_pre")) {
482 // skip
483 } else {
484 const int calls_len = sizeof(calls) / sizeof(calls[0]);
485 int i = 0;
486 for (; i < calls_len; i++) {
487 if (!strcmp(calls[i].name, call->_name)) {
488 break;
489 }
490 }
491 if (i != calls_len) {
492 const uint args_len = sizeof(calls[0].args) / sizeof(calls[0].args[0]);
493 for (uint j = 0; j < args_len; j++) {
494 int pos = calls[i].args[j].pos;
495 if (pos == -1) {
496 break;
497 }
498 if (!verify_helper(call->in(pos), phis, visited, calls[i].args[j].t, trace, barriers_used)) {
499 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
500 }
501 }
502 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
503 if (call->in(j)->bottom_type()->make_ptr() &&
504 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
505 uint k = 0;
506 for (; k < args_len && calls[i].args[k].pos != (int)j; k++);
507 if (k == args_len) {
508 fatal("arg %d for call %s not covered", j, call->_name);
509 }
510 }
511 }
512 } else {
513 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
514 if (call->in(j)->bottom_type()->make_ptr() &&
515 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
516 fatal("%s not covered", call->_name);
517 }
518 }
519 }
520 }
521 } else if (n->Opcode() == Op_ShenandoahEnqueueBarrier || n->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
522 // skip
523 } else if (n->is_AddP()
524 || n->is_Phi()
525 || n->is_ConstraintCast()
526 || n->Opcode() == Op_Return
527 || n->Opcode() == Op_CMoveP
528 || n->Opcode() == Op_CMoveN
529 || n->Opcode() == Op_Rethrow
530 || n->is_MemBar()
531 || n->Opcode() == Op_Conv2B
532 || n->Opcode() == Op_SafePoint
533 || n->is_CallJava()
534 || n->Opcode() == Op_Unlock
535 || n->Opcode() == Op_EncodeP
536 || n->Opcode() == Op_DecodeN) {
537 // nothing to do
538 } else {
539 static struct {
540 int opcode;
541 struct {
542 int pos;
543 verify_type t;
544 } inputs[2];
545 } others[] = {
546 Op_FastLock,
547 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
548 Op_Lock,
549 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone} },
550 Op_ArrayCopy,
551 { { ArrayCopyNode::Src, ShenandoahLoad }, { ArrayCopyNode::Dest, ShenandoahStore } },
552 Op_StrCompressedCopy,
553 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
554 Op_StrInflatedCopy,
555 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
556 Op_AryEq,
557 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
558 Op_StrIndexOf,
559 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
560 Op_StrComp,
561 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
562 Op_StrEquals,
563 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
564 Op_EncodeISOArray,
565 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
566 Op_HasNegatives,
567 { { 2, ShenandoahLoad }, { -1, ShenandoahNone} },
568 Op_CastP2X,
569 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
570 Op_StrIndexOfChar,
571 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
572 };
573
574 const int others_len = sizeof(others) / sizeof(others[0]);
575 int i = 0;
576 for (; i < others_len; i++) {
577 if (others[i].opcode == n->Opcode()) {
578 break;
579 }
580 }
581 uint stop = n->is_Call() ? n->as_Call()->tf()->domain()->cnt() : n->req();
582 if (i != others_len) {
583 const uint inputs_len = sizeof(others[0].inputs) / sizeof(others[0].inputs[0]);
584 for (uint j = 0; j < inputs_len; j++) {
585 int pos = others[i].inputs[j].pos;
586 if (pos == -1) {
587 break;
588 }
589 if (!verify_helper(n->in(pos), phis, visited, others[i].inputs[j].t, trace, barriers_used)) {
590 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
591 }
592 }
593 for (uint j = 1; j < stop; j++) {
594 if (n->in(j) != NULL && n->in(j)->bottom_type()->make_ptr() &&
595 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
596 uint k = 0;
597 for (; k < inputs_len && others[i].inputs[k].pos != (int)j; k++);
598 if (k == inputs_len) {
599 fatal("arg %d for node %s not covered", j, n->Name());
600 }
601 }
602 }
603 } else {
604 for (uint j = 1; j < stop; j++) {
605 if (n->in(j) != NULL && n->in(j)->bottom_type()->make_ptr() &&
606 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
607 fatal("%s not covered", n->Name());
608 }
609 }
610 }
611 }
612
613 if (n->is_SafePoint()) {
614 SafePointNode* sfpt = n->as_SafePoint();
615 if (verify_no_useless_barrier && sfpt->jvms() != NULL) {
616 for (uint i = sfpt->jvms()->scloff(); i < sfpt->jvms()->endoff(); i++) {
617 if (!verify_helper(sfpt->in(i), phis, visited, ShenandoahLoad, trace, barriers_used)) {
618 phis.clear();
619 visited.reset();
620 }
621 }
622 }
623 }
624 }
625
626 if (verify_no_useless_barrier) {
627 for (int i = 0; i < barriers.length(); i++) {
628 Node* n = barriers.at(i);
629 if (!barriers_used.member(n)) {
630 tty->print("XXX useless barrier"); n->dump(-2);
631 ShouldNotReachHere();
632 }
633 }
634 }
635 }
636 #endif
637
638 bool ShenandoahBarrierC2Support::is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase) {
639 // That both nodes have the same control is not sufficient to prove
640 // domination, verify that there's no path from d to n
641 ResourceMark rm;
642 Unique_Node_List wq;
643 wq.push(d);
644 for (uint next = 0; next < wq.size(); next++) {
645 Node *m = wq.at(next);
646 if (m == n) {
647 return false;
648 }
649 if (m->is_Phi() && m->in(0)->is_Loop()) {
650 assert(phase->ctrl_or_self(m->in(LoopNode::EntryControl)) != c, "following loop entry should lead to new control");
651 } else {
652 if (m->is_Store() || m->is_LoadStore()) {
653 // Take anti-dependencies into account
654 Node* mem = m->in(MemNode::Memory);
655 for (DUIterator_Fast imax, i = mem->fast_outs(imax); i < imax; i++) {
656 Node* u = mem->fast_out(i);
657 if (u->is_Load() && phase->C->can_alias(m->adr_type(), phase->C->get_alias_index(u->adr_type())) &&
658 phase->ctrl_or_self(u) == c) {
659 wq.push(u);
660 }
661 }
662 }
663 for (uint i = 0; i < m->req(); i++) {
664 if (m->in(i) != NULL && phase->ctrl_or_self(m->in(i)) == c) {
665 wq.push(m->in(i));
666 }
667 }
668 }
669 }
670 return true;
671 }
672
673 bool ShenandoahBarrierC2Support::is_dominator(Node* d_c, Node* n_c, Node* d, Node* n, PhaseIdealLoop* phase) {
674 if (d_c != n_c) {
675 return phase->is_dominator(d_c, n_c);
676 }
677 return is_dominator_same_ctrl(d_c, d, n, phase);
678 }
679
680 Node* next_mem(Node* mem, int alias) {
681 Node* res = NULL;
682 if (mem->is_Proj()) {
683 res = mem->in(0);
684 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
685 res = mem->in(TypeFunc::Memory);
686 } else if (mem->is_Phi()) {
687 res = mem->in(1);
688 } else if (mem->is_MergeMem()) {
689 res = mem->as_MergeMem()->memory_at(alias);
690 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
691 assert(alias = Compile::AliasIdxRaw, "following raw memory can't lead to a barrier");
692 res = mem->in(MemNode::Memory);
693 } else {
694 #ifdef ASSERT
695 mem->dump();
696 #endif
697 ShouldNotReachHere();
698 }
699 return res;
700 }
701
702 Node* ShenandoahBarrierC2Support::no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase) {
703 Node* iffproj = NULL;
704 while (c != dom) {
705 Node* next = phase->idom(c);
706 assert(next->unique_ctrl_out() == c || c->is_Proj() || c->is_Region(), "multiple control flow out but no proj or region?");
707 if (c->is_Region()) {
708 ResourceMark rm;
709 Unique_Node_List wq;
710 wq.push(c);
711 for (uint i = 0; i < wq.size(); i++) {
712 Node *n = wq.at(i);
713 if (n == next) {
714 continue;
715 }
716 if (n->is_Region()) {
717 for (uint j = 1; j < n->req(); j++) {
718 wq.push(n->in(j));
719 }
720 } else {
721 wq.push(n->in(0));
722 }
723 }
724 for (uint i = 0; i < wq.size(); i++) {
725 Node *n = wq.at(i);
726 assert(n->is_CFG(), "");
727 if (n->is_Multi()) {
728 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
729 Node* u = n->fast_out(j);
730 if (u->is_CFG()) {
731 if (!wq.member(u) && !u->as_Proj()->is_uncommon_trap_proj(Deoptimization::Reason_none)) {
732 return NodeSentinel;
733 }
734 }
735 }
736 }
737 }
738 } else if (c->is_Proj()) {
739 if (c->is_IfProj()) {
740 if (c->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) != NULL) {
741 // continue;
742 } else {
743 if (!allow_one_proj) {
744 return NodeSentinel;
745 }
746 if (iffproj == NULL) {
747 iffproj = c;
748 } else {
749 return NodeSentinel;
750 }
751 }
752 } else if (c->Opcode() == Op_JumpProj) {
753 return NodeSentinel; // unsupported
754 } else if (c->Opcode() == Op_CatchProj) {
755 return NodeSentinel; // unsupported
756 } else if (c->Opcode() == Op_CProj && next->Opcode() == Op_NeverBranch) {
757 return NodeSentinel; // unsupported
758 } else {
759 assert(next->unique_ctrl_out() == c, "unsupported branch pattern");
760 }
761 }
762 c = next;
763 }
764 return iffproj;
765 }
766
767 Node* ShenandoahBarrierC2Support::dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase) {
768 ResourceMark rm;
769 VectorSet wq(Thread::current()->resource_area());
770 wq.set(mem->_idx);
771 mem_ctrl = phase->ctrl_or_self(mem);
772 while (!phase->is_dominator(mem_ctrl, ctrl) || mem_ctrl == ctrl) {
773 mem = next_mem(mem, alias);
774 if (wq.test_set(mem->_idx)) {
775 return NULL;
776 }
777 mem_ctrl = phase->ctrl_or_self(mem);
778 }
779 if (mem->is_MergeMem()) {
780 mem = mem->as_MergeMem()->memory_at(alias);
781 mem_ctrl = phase->ctrl_or_self(mem);
782 }
783 return mem;
784 }
785
786 Node* ShenandoahBarrierC2Support::find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase) {
787 Node* mem = NULL;
788 Node* c = ctrl;
789 do {
790 if (c->is_Region()) {
791 Node* phi_bottom = NULL;
792 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax && mem == NULL; i++) {
793 Node* u = c->fast_out(i);
794 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
795 if (u->adr_type() == TypePtr::BOTTOM) {
796 mem = u;
797 }
798 }
799 }
800 } else {
801 if (c->is_Call() && c->as_Call()->adr_type() != NULL) {
802 CallProjections projs;
803 c->as_Call()->extract_projections(&projs, true, false);
804 if (projs.fallthrough_memproj != NULL) {
805 if (projs.fallthrough_memproj->adr_type() == TypePtr::BOTTOM) {
806 if (projs.catchall_memproj == NULL) {
807 mem = projs.fallthrough_memproj;
808 } else {
809 if (phase->is_dominator(projs.fallthrough_catchproj, ctrl)) {
810 mem = projs.fallthrough_memproj;
811 } else {
812 assert(phase->is_dominator(projs.catchall_catchproj, ctrl), "one proj must dominate barrier");
813 mem = projs.catchall_memproj;
814 }
815 }
816 }
817 } else {
818 Node* proj = c->as_Call()->proj_out(TypeFunc::Memory);
819 if (proj != NULL &&
820 proj->adr_type() == TypePtr::BOTTOM) {
821 mem = proj;
822 }
823 }
824 } else {
825 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
826 Node* u = c->fast_out(i);
827 if (u->is_Proj() &&
828 u->bottom_type() == Type::MEMORY &&
829 u->adr_type() == TypePtr::BOTTOM) {
830 assert(c->is_SafePoint() || c->is_MemBar() || c->is_Start(), "");
831 assert(mem == NULL, "only one proj");
832 mem = u;
833 }
834 }
835 assert(!c->is_Call() || c->as_Call()->adr_type() != NULL || mem == NULL, "no mem projection expected");
836 }
837 }
838 c = phase->idom(c);
839 } while (mem == NULL);
840 return mem;
841 }
842
843 void ShenandoahBarrierC2Support::follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase) {
844 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
845 Node* u = n->fast_out(i);
846 if (!u->is_CFG() && phase->get_ctrl(u) == ctrl && (!u->is_Phi() || !u->in(0)->is_Loop() || u->in(LoopNode::LoopBackControl) != n)) {
847 uses.push(u);
848 }
849 }
850 }
851
852 static void hide_strip_mined_loop(OuterStripMinedLoopNode* outer, CountedLoopNode* inner, PhaseIdealLoop* phase) {
853 OuterStripMinedLoopEndNode* le = inner->outer_loop_end();
854 Node* new_outer = new LoopNode(outer->in(LoopNode::EntryControl), outer->in(LoopNode::LoopBackControl));
855 phase->register_control(new_outer, phase->get_loop(outer), outer->in(LoopNode::EntryControl));
856 Node* new_le = new IfNode(le->in(0), le->in(1), le->_prob, le->_fcnt);
857 phase->register_control(new_le, phase->get_loop(le), le->in(0));
858 phase->lazy_replace(outer, new_outer);
859 phase->lazy_replace(le, new_le);
860 inner->clear_strip_mined();
861 }
862
863 void ShenandoahBarrierC2Support::test_gc_state(Node*& ctrl, Node* raw_mem, Node*& test_fail_ctrl,
864 PhaseIdealLoop* phase, int flags) {
865 PhaseIterGVN& igvn = phase->igvn();
866 Node* old_ctrl = ctrl;
867
868 Node* thread = new ThreadLocalNode();
869 Node* gc_state_offset = igvn.MakeConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
870 Node* gc_state_addr = new AddPNode(phase->C->top(), thread, gc_state_offset);
871 Node* gc_state = new LoadBNode(old_ctrl, raw_mem, gc_state_addr,
872 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(NULL),
873 TypeInt::BYTE, MemNode::unordered);
874 Node* gc_state_and = new AndINode(gc_state, igvn.intcon(flags));
875 Node* gc_state_cmp = new CmpINode(gc_state_and, igvn.zerocon(T_INT));
876 Node* gc_state_bool = new BoolNode(gc_state_cmp, BoolTest::ne);
877
878 IfNode* gc_state_iff = new IfNode(old_ctrl, gc_state_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
879 ctrl = new IfTrueNode(gc_state_iff);
880 test_fail_ctrl = new IfFalseNode(gc_state_iff);
881
882 IdealLoopTree* loop = phase->get_loop(ctrl);
883 phase->register_control(gc_state_iff, loop, old_ctrl);
884 phase->register_control(ctrl, loop, gc_state_iff);
885 phase->register_control(test_fail_ctrl, loop, gc_state_iff);
886
887 phase->register_new_node(thread, old_ctrl);
888 phase->register_new_node(gc_state_addr, old_ctrl);
889 phase->register_new_node(gc_state, old_ctrl);
890 phase->register_new_node(gc_state_and, old_ctrl);
891 phase->register_new_node(gc_state_cmp, old_ctrl);
892 phase->register_new_node(gc_state_bool, old_ctrl);
893
894 phase->set_ctrl(gc_state_offset, phase->C->root());
895
896 assert(is_gc_state_test(gc_state_iff, flags), "Should match the shape");
897 }
898
899 void ShenandoahBarrierC2Support::test_null(Node*& ctrl, Node* val, Node*& null_ctrl, PhaseIdealLoop* phase) {
900 Node* old_ctrl = ctrl;
901 PhaseIterGVN& igvn = phase->igvn();
902
903 const Type* val_t = igvn.type(val);
904 if (val_t->meet(TypePtr::NULL_PTR) == val_t) {
905 Node* null_cmp = new CmpPNode(val, igvn.zerocon(T_OBJECT));
906 Node* null_test = new BoolNode(null_cmp, BoolTest::ne);
907
908 IfNode* null_iff = new IfNode(old_ctrl, null_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
909 ctrl = new IfTrueNode(null_iff);
910 null_ctrl = new IfFalseNode(null_iff);
911
912 IdealLoopTree* loop = phase->get_loop(old_ctrl);
913 phase->register_control(null_iff, loop, old_ctrl);
914 phase->register_control(ctrl, loop, null_iff);
915 phase->register_control(null_ctrl, loop, null_iff);
916
917 phase->register_new_node(null_cmp, old_ctrl);
918 phase->register_new_node(null_test, old_ctrl);
919 }
920 }
921
922 void ShenandoahBarrierC2Support::test_in_cset(Node*& ctrl, Node*& not_cset_ctrl, Node* val, Node* raw_mem, PhaseIdealLoop* phase) {
923 Node* old_ctrl = ctrl;
924 PhaseIterGVN& igvn = phase->igvn();
925
926 Node* raw_val = new CastP2XNode(old_ctrl, val);
927 Node* cset_idx = new URShiftXNode(raw_val, igvn.intcon(ShenandoahHeapRegion::region_size_bytes_shift_jint()));
928 Node* cset_addr = igvn.makecon(TypeRawPtr::make(ShenandoahHeap::in_cset_fast_test_addr()));
929 Node* cset_load_addr = new AddPNode(phase->C->top(), cset_addr, cset_idx);
930 Node* cset_load = new LoadBNode(old_ctrl, raw_mem, cset_load_addr,
931 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(NULL),
932 TypeInt::BYTE, MemNode::unordered);
933 Node* cset_cmp = new CmpINode(cset_load, igvn.zerocon(T_INT));
934 Node* cset_bool = new BoolNode(cset_cmp, BoolTest::ne);
935
936 IfNode* cset_iff = new IfNode(old_ctrl, cset_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
937 ctrl = new IfTrueNode(cset_iff);
938 not_cset_ctrl = new IfFalseNode(cset_iff);
939
940 IdealLoopTree *loop = phase->get_loop(old_ctrl);
941 phase->register_control(cset_iff, loop, old_ctrl);
942 phase->register_control(ctrl, loop, cset_iff);
943 phase->register_control(not_cset_ctrl, loop, cset_iff);
944
945 phase->set_ctrl(cset_addr, phase->C->root());
946
947 phase->register_new_node(raw_val, old_ctrl);
948 phase->register_new_node(cset_idx, old_ctrl);
949 phase->register_new_node(cset_load_addr, old_ctrl);
950 phase->register_new_node(cset_load, old_ctrl);
951 phase->register_new_node(cset_cmp, old_ctrl);
952 phase->register_new_node(cset_bool, old_ctrl);
953 }
954
955 void ShenandoahBarrierC2Support::call_lrb_stub(Node*& ctrl, Node*& val, Node* load_addr, Node*& result_mem, Node* raw_mem, bool is_native, PhaseIdealLoop* phase) {
956 IdealLoopTree*loop = phase->get_loop(ctrl);
957 const TypePtr* obj_type = phase->igvn().type(val)->is_oopptr();
958
959 // The slow path stub consumes and produces raw memory in addition
960 // to the existing memory edges
961 Node* base = find_bottom_mem(ctrl, phase);
962 MergeMemNode* mm = MergeMemNode::make(base);
963 mm->set_memory_at(Compile::AliasIdxRaw, raw_mem);
964 phase->register_new_node(mm, ctrl);
965
966 address target = LP64_ONLY(UseCompressedOops) NOT_LP64(false) ?
967 CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_narrow) :
968 CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier);
969
970 address calladdr = is_native ? CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_native)
971 : target;
972 const char* name = is_native ? "load_reference_barrier_native" : "load_reference_barrier";
973 Node* call = new CallLeafNode(ShenandoahBarrierSetC2::shenandoah_load_reference_barrier_Type(obj_type), calladdr, name, TypeRawPtr::BOTTOM);
974
975 call->init_req(TypeFunc::Control, ctrl);
976 call->init_req(TypeFunc::I_O, phase->C->top());
977 call->init_req(TypeFunc::Memory, mm);
978 call->init_req(TypeFunc::FramePtr, phase->C->top());
979 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
980 call->init_req(TypeFunc::Parms, val);
981 call->init_req(TypeFunc::Parms+1, load_addr);
982 phase->register_control(call, loop, ctrl);
983 ctrl = new ProjNode(call, TypeFunc::Control);
984 phase->register_control(ctrl, loop, call);
985 result_mem = new ProjNode(call, TypeFunc::Memory);
986 phase->register_new_node(result_mem, call);
987 val = new ProjNode(call, TypeFunc::Parms);
988 phase->register_new_node(val, call);
989 }
990
991 void ShenandoahBarrierC2Support::fix_ctrl(Node* barrier, Node* region, const MemoryGraphFixer& fixer, Unique_Node_List& uses, Unique_Node_List& uses_to_ignore, uint last, PhaseIdealLoop* phase) {
992 Node* ctrl = phase->get_ctrl(barrier);
993 Node* init_raw_mem = fixer.find_mem(ctrl, barrier);
994
995 // Update the control of all nodes that should be after the
996 // barrier control flow
997 uses.clear();
998 // Every node that is control dependent on the barrier's input
999 // control will be after the expanded barrier. The raw memory (if
1000 // its memory is control dependent on the barrier's input control)
1001 // must stay above the barrier.
1002 uses_to_ignore.clear();
1003 if (phase->has_ctrl(init_raw_mem) && phase->get_ctrl(init_raw_mem) == ctrl && !init_raw_mem->is_Phi()) {
1004 uses_to_ignore.push(init_raw_mem);
1005 }
1006 for (uint next = 0; next < uses_to_ignore.size(); next++) {
1007 Node *n = uses_to_ignore.at(next);
1008 for (uint i = 0; i < n->req(); i++) {
1009 Node* in = n->in(i);
1010 if (in != NULL && phase->has_ctrl(in) && phase->get_ctrl(in) == ctrl) {
1011 uses_to_ignore.push(in);
1012 }
1013 }
1014 }
1015 for (DUIterator_Fast imax, i = ctrl->fast_outs(imax); i < imax; i++) {
1016 Node* u = ctrl->fast_out(i);
1017 if (u->_idx < last &&
1018 u != barrier &&
1019 !uses_to_ignore.member(u) &&
1020 (u->in(0) != ctrl || (!u->is_Region() && !u->is_Phi())) &&
1021 (ctrl->Opcode() != Op_CatchProj || u->Opcode() != Op_CreateEx)) {
1022 Node* old_c = phase->ctrl_or_self(u);
1023 Node* c = old_c;
1024 if (c != ctrl ||
1025 is_dominator_same_ctrl(old_c, barrier, u, phase) ||
1026 ShenandoahBarrierSetC2::is_shenandoah_state_load(u)) {
1027 phase->igvn().rehash_node_delayed(u);
1028 int nb = u->replace_edge(ctrl, region);
1029 if (u->is_CFG()) {
1030 if (phase->idom(u) == ctrl) {
1031 phase->set_idom(u, region, phase->dom_depth(region));
1032 }
1033 } else if (phase->get_ctrl(u) == ctrl) {
1034 assert(u != init_raw_mem, "should leave input raw mem above the barrier");
1035 uses.push(u);
1036 }
1037 assert(nb == 1, "more than 1 ctrl input?");
1038 --i, imax -= nb;
1039 }
1040 }
1041 }
1042 }
1043
1044 static Node* create_phis_on_call_return(Node* ctrl, Node* c, Node* n, Node* n_clone, const CallProjections& projs, PhaseIdealLoop* phase) {
1045 Node* region = NULL;
1046 while (c != ctrl) {
1047 if (c->is_Region()) {
1048 region = c;
1049 }
1050 c = phase->idom(c);
1051 }
1052 assert(region != NULL, "");
1053 Node* phi = new PhiNode(region, n->bottom_type());
1054 for (uint j = 1; j < region->req(); j++) {
1055 Node* in = region->in(j);
1056 if (phase->is_dominator(projs.fallthrough_catchproj, in)) {
1057 phi->init_req(j, n);
1058 } else if (phase->is_dominator(projs.catchall_catchproj, in)) {
1059 phi->init_req(j, n_clone);
1060 } else {
1061 phi->init_req(j, create_phis_on_call_return(ctrl, in, n, n_clone, projs, phase));
1062 }
1063 }
1064 phase->register_new_node(phi, region);
1065 return phi;
1066 }
1067
1068 void ShenandoahBarrierC2Support::pin_and_expand(PhaseIdealLoop* phase) {
1069 ShenandoahBarrierSetC2State* state = ShenandoahBarrierSetC2::bsc2()->state();
1070
1071 Unique_Node_List uses;
1072 for (int i = 0; i < state->enqueue_barriers_count(); i++) {
1073 Node* barrier = state->enqueue_barrier(i);
1074 Node* ctrl = phase->get_ctrl(barrier);
1075 IdealLoopTree* loop = phase->get_loop(ctrl);
1076 if (loop->_head->is_OuterStripMinedLoop()) {
1077 // Expanding a barrier here will break loop strip mining
1078 // verification. Transform the loop so the loop nest doesn't
1079 // appear as strip mined.
1080 OuterStripMinedLoopNode* outer = loop->_head->as_OuterStripMinedLoop();
1081 hide_strip_mined_loop(outer, outer->unique_ctrl_out()->as_CountedLoop(), phase);
1082 }
1083 }
1084
1085 Node_Stack stack(0);
1086 Node_List clones;
1087 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1088 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1089 if (lrb->is_redundant()) {
1090 continue;
1091 }
1092
1093 Node* ctrl = phase->get_ctrl(lrb);
1094 if ((ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) || ctrl->is_CallJava()) {
1095 CallNode* call = ctrl->is_Proj() ? ctrl->in(0)->as_CallJava() : ctrl->as_CallJava();
1096 if (call->entry_point() == OptoRuntime::rethrow_stub()) {
1097 // The rethrow call may have too many projections to be
1098 // properly handled here. Given there's no reason for a
1099 // barrier to depend on the call, move it above the call
1100 stack.push(lrb, 0);
1101 do {
1102 Node* n = stack.node();
1103 uint idx = stack.index();
1104 if (idx < n->req()) {
1105 Node* in = n->in(idx);
1106 stack.set_index(idx+1);
1107 if (in != NULL) {
1108 if (phase->has_ctrl(in)) {
1109 if (phase->is_dominator(call, phase->get_ctrl(in))) {
1110 #ifdef ASSERT
1111 for (uint i = 0; i < stack.size(); i++) {
1112 assert(stack.node_at(i) != in, "node shouldn't have been seen yet");
1113 }
1114 #endif
1115 stack.push(in, 0);
1116 }
1117 } else {
1118 assert(phase->is_dominator(in, call->in(0)), "no dependency on the call");
1119 }
1120 }
1121 } else {
1122 phase->set_ctrl(n, call->in(0));
1123 stack.pop();
1124 }
1125 } while(stack.size() > 0);
1126 continue;
1127 }
1128 CallProjections projs;
1129 call->extract_projections(&projs, false, false);
1130
1131 Node* lrb_clone = lrb->clone();
1132 phase->register_new_node(lrb_clone, projs.catchall_catchproj);
1133 phase->set_ctrl(lrb, projs.fallthrough_catchproj);
1134
1135 stack.push(lrb, 0);
1136 clones.push(lrb_clone);
1137
1138 do {
1139 assert(stack.size() == clones.size(), "");
1140 Node* n = stack.node();
1141 #ifdef ASSERT
1142 if (n->is_Load()) {
1143 Node* mem = n->in(MemNode::Memory);
1144 for (DUIterator_Fast jmax, j = mem->fast_outs(jmax); j < jmax; j++) {
1145 Node* u = mem->fast_out(j);
1146 assert(!u->is_Store() || !u->is_LoadStore() || phase->get_ctrl(u) != ctrl, "anti dependent store?");
1147 }
1148 }
1149 #endif
1150 uint idx = stack.index();
1151 Node* n_clone = clones.at(clones.size()-1);
1152 if (idx < n->outcnt()) {
1153 Node* u = n->raw_out(idx);
1154 Node* c = phase->ctrl_or_self(u);
1155 if (phase->is_dominator(call, c) && phase->is_dominator(c, projs.fallthrough_proj)) {
1156 stack.set_index(idx+1);
1157 assert(!u->is_CFG(), "");
1158 stack.push(u, 0);
1159 Node* u_clone = u->clone();
1160 int nb = u_clone->replace_edge(n, n_clone);
1161 assert(nb > 0, "should have replaced some uses");
1162 phase->register_new_node(u_clone, projs.catchall_catchproj);
1163 clones.push(u_clone);
1164 phase->set_ctrl(u, projs.fallthrough_catchproj);
1165 } else {
1166 bool replaced = false;
1167 if (u->is_Phi()) {
1168 for (uint k = 1; k < u->req(); k++) {
1169 if (u->in(k) == n) {
1170 if (phase->is_dominator(projs.catchall_catchproj, u->in(0)->in(k))) {
1171 phase->igvn().replace_input_of(u, k, n_clone);
1172 replaced = true;
1173 } else if (!phase->is_dominator(projs.fallthrough_catchproj, u->in(0)->in(k))) {
1174 phase->igvn().replace_input_of(u, k, create_phis_on_call_return(ctrl, u->in(0)->in(k), n, n_clone, projs, phase));
1175 replaced = true;
1176 }
1177 }
1178 }
1179 } else {
1180 if (phase->is_dominator(projs.catchall_catchproj, c)) {
1181 phase->igvn().rehash_node_delayed(u);
1182 int nb = u->replace_edge(n, n_clone);
1183 assert(nb > 0, "should have replaced some uses");
1184 replaced = true;
1185 } else if (!phase->is_dominator(projs.fallthrough_catchproj, c)) {
1186 phase->igvn().rehash_node_delayed(u);
1187 int nb = u->replace_edge(n, create_phis_on_call_return(ctrl, c, n, n_clone, projs, phase));
1188 assert(nb > 0, "should have replaced some uses");
1189 replaced = true;
1190 }
1191 }
1192 if (!replaced) {
1193 stack.set_index(idx+1);
1194 }
1195 }
1196 } else {
1197 stack.pop();
1198 clones.pop();
1199 }
1200 } while (stack.size() > 0);
1201 assert(stack.size() == 0 && clones.size() == 0, "");
1202 }
1203 }
1204
1205 for (int i = 0; i < state->load_reference_barriers_count(); i++) {
1206 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1207 if (lrb->is_redundant()) {
1208 continue;
1209 }
1210 Node* ctrl = phase->get_ctrl(lrb);
1211 IdealLoopTree* loop = phase->get_loop(ctrl);
1212 if (loop->_head->is_OuterStripMinedLoop()) {
1213 // Expanding a barrier here will break loop strip mining
1214 // verification. Transform the loop so the loop nest doesn't
1215 // appear as strip mined.
1216 OuterStripMinedLoopNode* outer = loop->_head->as_OuterStripMinedLoop();
1217 hide_strip_mined_loop(outer, outer->unique_ctrl_out()->as_CountedLoop(), phase);
1218 }
1219 }
1220
1221 // Expand load-reference-barriers
1222 MemoryGraphFixer fixer(Compile::AliasIdxRaw, true, phase);
1223 Unique_Node_List uses_to_ignore;
1224 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1225 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1226 if (lrb->is_redundant()) {
1227 phase->igvn().replace_node(lrb, lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn));
1228 continue;
1229 }
1230 uint last = phase->C->unique();
1231 Node* ctrl = phase->get_ctrl(lrb);
1232 Node* val = lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
1233
1234 Node* orig_ctrl = ctrl;
1235
1236 Node* raw_mem = fixer.find_mem(ctrl, lrb);
1237 Node* init_raw_mem = raw_mem;
1238 Node* raw_mem_for_ctrl = fixer.find_mem(ctrl, NULL);
1239
1240 IdealLoopTree* loop = phase->get_loop(ctrl);
1241
1242 assert(val->bottom_type()->make_oopptr(), "need oop");
1243 assert(val->bottom_type()->make_oopptr()->const_oop() == NULL, "expect non-constant");
1244
1245 enum { _heap_stable = 1, _not_cset, _evac_path, PATH_LIMIT };
1246 Node* region = new RegionNode(PATH_LIMIT);
1247 Node* val_phi = new PhiNode(region, val->bottom_type()->is_oopptr());
1248 Node* raw_mem_phi = PhiNode::make(region, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
1249
1250 // Stable path.
1251 Node* heap_stable_ctrl = NULL;
1252 test_gc_state(ctrl, raw_mem, heap_stable_ctrl, phase, ShenandoahHeap::HAS_FORWARDED);
1253 IfNode* heap_stable_iff = heap_stable_ctrl->in(0)->as_If();
1254
1255 // Heap stable case
1256 region->init_req(_heap_stable, heap_stable_ctrl);
1257 val_phi->init_req(_heap_stable, val);
1258 raw_mem_phi->init_req(_heap_stable, raw_mem);
1259
1260 // Test for in-cset.
1261 // Wires !in_cset(obj) to slot 2 of region and phis
1262 Node* not_cset_ctrl = NULL;
1263 test_in_cset(ctrl, not_cset_ctrl, val, raw_mem, phase);
1264 if (not_cset_ctrl != NULL) {
1265 region->init_req(_not_cset, not_cset_ctrl);
1266 val_phi->init_req(_not_cset, val);
1267 raw_mem_phi->init_req(_not_cset, raw_mem);
1268 }
1269
1270 // Call lrb-stub and wire up that path in slots 4
1271 Node* result_mem = NULL;
1272
1273 Node* addr;
1274 if (ShenandoahSelfFixing) {
1275 VectorSet visited(Thread::current()->resource_area());
1276 addr = get_load_addr(phase, visited, lrb);
1277 } else {
1278 addr = phase->igvn().zerocon(T_OBJECT);
1279 }
1280 if (addr->Opcode() == Op_AddP) {
1281 Node* orig_base = addr->in(AddPNode::Base);
1282 Node* base = new CheckCastPPNode(ctrl, orig_base, orig_base->bottom_type(), true);
1283 phase->register_new_node(base, ctrl);
1284 if (addr->in(AddPNode::Base) == addr->in((AddPNode::Address))) {
1285 // Field access
1286 addr = addr->clone();
1287 addr->set_req(AddPNode::Base, base);
1288 addr->set_req(AddPNode::Address, base);
1289 phase->register_new_node(addr, ctrl);
1290 } else {
1291 Node* addr2 = addr->in(AddPNode::Address);
1292 if (addr2->Opcode() == Op_AddP && addr2->in(AddPNode::Base) == addr2->in(AddPNode::Address) &&
1293 addr2->in(AddPNode::Base) == orig_base) {
1294 addr2 = addr2->clone();
1295 addr2->set_req(AddPNode::Base, base);
1296 addr2->set_req(AddPNode::Address, base);
1297 phase->register_new_node(addr2, ctrl);
1298 addr = addr->clone();
1299 addr->set_req(AddPNode::Base, base);
1300 addr->set_req(AddPNode::Address, addr2);
1301 phase->register_new_node(addr, ctrl);
1302 }
1303 }
1304 }
1305 call_lrb_stub(ctrl, val, addr, result_mem, raw_mem, lrb->is_native(), phase);
1306 region->init_req(_evac_path, ctrl);
1307 val_phi->init_req(_evac_path, val);
1308 raw_mem_phi->init_req(_evac_path, result_mem);
1309
1310 phase->register_control(region, loop, heap_stable_iff);
1311 Node* out_val = val_phi;
1312 phase->register_new_node(val_phi, region);
1313 phase->register_new_node(raw_mem_phi, region);
1314
1315 fix_ctrl(lrb, region, fixer, uses, uses_to_ignore, last, phase);
1316
1317 ctrl = orig_ctrl;
1318
1319 phase->igvn().replace_node(lrb, out_val);
1320
1321 follow_barrier_uses(out_val, ctrl, uses, phase);
1322
1323 for(uint next = 0; next < uses.size(); next++ ) {
1324 Node *n = uses.at(next);
1325 assert(phase->get_ctrl(n) == ctrl, "bad control");
1326 assert(n != init_raw_mem, "should leave input raw mem above the barrier");
1327 phase->set_ctrl(n, region);
1328 follow_barrier_uses(n, ctrl, uses, phase);
1329 }
1330
1331 // The slow path call produces memory: hook the raw memory phi
1332 // from the expanded load reference barrier with the rest of the graph
1333 // which may require adding memory phis at every post dominated
1334 // region and at enclosing loop heads. Use the memory state
1335 // collected in memory_nodes to fix the memory graph. Update that
1336 // memory state as we go.
1337 fixer.fix_mem(ctrl, region, init_raw_mem, raw_mem_for_ctrl, raw_mem_phi, uses);
1338 }
1339 // Done expanding load-reference-barriers.
1340 assert(ShenandoahBarrierSetC2::bsc2()->state()->load_reference_barriers_count() == 0, "all load reference barrier nodes should have been replaced");
1341
1342 for (int i = state->enqueue_barriers_count() - 1; i >= 0; i--) {
1343 Node* barrier = state->enqueue_barrier(i);
1344 Node* pre_val = barrier->in(1);
1345
1346 if (phase->igvn().type(pre_val)->higher_equal(TypePtr::NULL_PTR)) {
1347 ShouldNotReachHere();
1348 continue;
1349 }
1350
1351 Node* ctrl = phase->get_ctrl(barrier);
1352
1353 if (ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) {
1354 assert(is_dominator(phase->get_ctrl(pre_val), ctrl->in(0)->in(0), pre_val, ctrl->in(0), phase), "can't move");
1355 ctrl = ctrl->in(0)->in(0);
1356 phase->set_ctrl(barrier, ctrl);
1357 } else if (ctrl->is_CallRuntime()) {
1358 assert(is_dominator(phase->get_ctrl(pre_val), ctrl->in(0), pre_val, ctrl, phase), "can't move");
1359 ctrl = ctrl->in(0);
1360 phase->set_ctrl(barrier, ctrl);
1361 }
1362
1363 Node* init_ctrl = ctrl;
1364 IdealLoopTree* loop = phase->get_loop(ctrl);
1365 Node* raw_mem = fixer.find_mem(ctrl, barrier);
1366 Node* init_raw_mem = raw_mem;
1367 Node* raw_mem_for_ctrl = fixer.find_mem(ctrl, NULL);
1368 Node* heap_stable_ctrl = NULL;
1369 Node* null_ctrl = NULL;
1370 uint last = phase->C->unique();
1371
1372 enum { _heap_stable = 1, _heap_unstable, PATH_LIMIT };
1373 Node* region = new RegionNode(PATH_LIMIT);
1374 Node* phi = PhiNode::make(region, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
1375
1376 enum { _fast_path = 1, _slow_path, _null_path, PATH_LIMIT2 };
1377 Node* region2 = new RegionNode(PATH_LIMIT2);
1378 Node* phi2 = PhiNode::make(region2, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
1379
1380 // Stable path.
1381 test_gc_state(ctrl, raw_mem, heap_stable_ctrl, phase, ShenandoahHeap::MARKING);
1382 region->init_req(_heap_stable, heap_stable_ctrl);
1383 phi->init_req(_heap_stable, raw_mem);
1384
1385 // Null path
1386 Node* reg2_ctrl = NULL;
1387 test_null(ctrl, pre_val, null_ctrl, phase);
1388 if (null_ctrl != NULL) {
1389 reg2_ctrl = null_ctrl->in(0);
1390 region2->init_req(_null_path, null_ctrl);
1391 phi2->init_req(_null_path, raw_mem);
1392 } else {
1393 region2->del_req(_null_path);
1394 phi2->del_req(_null_path);
1395 }
1396
1397 const int index_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset());
1398 const int buffer_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset());
1399 Node* thread = new ThreadLocalNode();
1400 phase->register_new_node(thread, ctrl);
1401 Node* buffer_adr = new AddPNode(phase->C->top(), thread, phase->igvn().MakeConX(buffer_offset));
1402 phase->register_new_node(buffer_adr, ctrl);
1403 Node* index_adr = new AddPNode(phase->C->top(), thread, phase->igvn().MakeConX(index_offset));
1404 phase->register_new_node(index_adr, ctrl);
1405
1406 BasicType index_bt = TypeX_X->basic_type();
1407 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 SATBMarkQueue::_index with wrong size.");
1408 const TypePtr* adr_type = TypeRawPtr::BOTTOM;
1409 Node* index = new LoadXNode(ctrl, raw_mem, index_adr, adr_type, TypeX_X, MemNode::unordered);
1410 phase->register_new_node(index, ctrl);
1411 Node* index_cmp = new CmpXNode(index, phase->igvn().MakeConX(0));
1412 phase->register_new_node(index_cmp, ctrl);
1413 Node* index_test = new BoolNode(index_cmp, BoolTest::ne);
1414 phase->register_new_node(index_test, ctrl);
1415 IfNode* queue_full_iff = new IfNode(ctrl, index_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
1416 if (reg2_ctrl == NULL) reg2_ctrl = queue_full_iff;
1417 phase->register_control(queue_full_iff, loop, ctrl);
1418 Node* not_full = new IfTrueNode(queue_full_iff);
1419 phase->register_control(not_full, loop, queue_full_iff);
1420 Node* full = new IfFalseNode(queue_full_iff);
1421 phase->register_control(full, loop, queue_full_iff);
1422
1423 ctrl = not_full;
1424
1425 Node* next_index = new SubXNode(index, phase->igvn().MakeConX(sizeof(intptr_t)));
1426 phase->register_new_node(next_index, ctrl);
1427
1428 Node* buffer = new LoadPNode(ctrl, raw_mem, buffer_adr, adr_type, TypeRawPtr::NOTNULL, MemNode::unordered);
1429 phase->register_new_node(buffer, ctrl);
1430 Node *log_addr = new AddPNode(phase->C->top(), buffer, next_index);
1431 phase->register_new_node(log_addr, ctrl);
1432 Node* log_store = new StorePNode(ctrl, raw_mem, log_addr, adr_type, pre_val, MemNode::unordered);
1433 phase->register_new_node(log_store, ctrl);
1434 // update the index
1435 Node* index_update = new StoreXNode(ctrl, log_store, index_adr, adr_type, next_index, MemNode::unordered);
1436 phase->register_new_node(index_update, ctrl);
1437
1438 // Fast-path case
1439 region2->init_req(_fast_path, ctrl);
1440 phi2->init_req(_fast_path, index_update);
1441
1442 ctrl = full;
1443
1444 Node* base = find_bottom_mem(ctrl, phase);
1445
1446 MergeMemNode* mm = MergeMemNode::make(base);
1447 mm->set_memory_at(Compile::AliasIdxRaw, raw_mem);
1448 phase->register_new_node(mm, ctrl);
1449
1450 Node* call = new CallLeafNode(ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type(), CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), "shenandoah_wb_pre", TypeRawPtr::BOTTOM);
1451 call->init_req(TypeFunc::Control, ctrl);
1452 call->init_req(TypeFunc::I_O, phase->C->top());
1453 call->init_req(TypeFunc::Memory, mm);
1454 call->init_req(TypeFunc::FramePtr, phase->C->top());
1455 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
1456 call->init_req(TypeFunc::Parms, pre_val);
1457 call->init_req(TypeFunc::Parms+1, thread);
1458 phase->register_control(call, loop, ctrl);
1459
1460 Node* ctrl_proj = new ProjNode(call, TypeFunc::Control);
1461 phase->register_control(ctrl_proj, loop, call);
1462 Node* mem_proj = new ProjNode(call, TypeFunc::Memory);
1463 phase->register_new_node(mem_proj, call);
1464
1465 // Slow-path case
1466 region2->init_req(_slow_path, ctrl_proj);
1467 phi2->init_req(_slow_path, mem_proj);
1468
1469 phase->register_control(region2, loop, reg2_ctrl);
1470 phase->register_new_node(phi2, region2);
1471
1472 region->init_req(_heap_unstable, region2);
1473 phi->init_req(_heap_unstable, phi2);
1474
1475 phase->register_control(region, loop, heap_stable_ctrl->in(0));
1476 phase->register_new_node(phi, region);
1477
1478 fix_ctrl(barrier, region, fixer, uses, uses_to_ignore, last, phase);
1479 for(uint next = 0; next < uses.size(); next++ ) {
1480 Node *n = uses.at(next);
1481 assert(phase->get_ctrl(n) == init_ctrl, "bad control");
1482 assert(n != init_raw_mem, "should leave input raw mem above the barrier");
1483 phase->set_ctrl(n, region);
1484 follow_barrier_uses(n, init_ctrl, uses, phase);
1485 }
1486 fixer.fix_mem(init_ctrl, region, init_raw_mem, raw_mem_for_ctrl, phi, uses);
1487
1488 phase->igvn().replace_node(barrier, pre_val);
1489 }
1490 assert(state->enqueue_barriers_count() == 0, "all enqueue barrier nodes should have been replaced");
1491
1492 }
1493
1494 Node* ShenandoahBarrierC2Support::get_load_addr(PhaseIdealLoop* phase, VectorSet& visited, Node* in) {
1495 if (visited.test_set(in->_idx)) {
1496 return NULL;
1497 }
1498 switch (in->Opcode()) {
1499 case Op_Proj:
1500 return get_load_addr(phase, visited, in->in(0));
1501 case Op_CastPP:
1502 case Op_CheckCastPP:
1503 case Op_DecodeN:
1504 case Op_EncodeP:
1505 return get_load_addr(phase, visited, in->in(1));
1506 case Op_LoadN:
1507 case Op_LoadP:
1508 return in->in(MemNode::Address);
1509 case Op_CompareAndExchangeN:
1510 case Op_CompareAndExchangeP:
1511 case Op_GetAndSetN:
1512 case Op_GetAndSetP:
1513 case Op_ShenandoahCompareAndExchangeP:
1514 case Op_ShenandoahCompareAndExchangeN:
1515 // Those instructions would just have stored a different
1516 // value into the field. No use to attempt to fix it at this point.
1517 return phase->igvn().zerocon(T_OBJECT);
1518 case Op_CMoveP:
1519 case Op_CMoveN: {
1520 Node* t = get_load_addr(phase, visited, in->in(CMoveNode::IfTrue));
1521 Node* f = get_load_addr(phase, visited, in->in(CMoveNode::IfFalse));
1522 // Handle unambiguous cases: single address reported on both branches.
1523 if (t != NULL && f == NULL) return t;
1524 if (t == NULL && f != NULL) return f;
1525 if (t != NULL && t == f) return t;
1526 // Ambiguity.
1527 return phase->igvn().zerocon(T_OBJECT);
1528 }
1529 case Op_Phi: {
1530 Node* addr = NULL;
1531 for (uint i = 1; i < in->req(); i++) {
1532 Node* addr1 = get_load_addr(phase, visited, in->in(i));
1533 if (addr == NULL) {
1534 addr = addr1;
1535 }
1536 if (addr != addr1) {
1537 return phase->igvn().zerocon(T_OBJECT);
1538 }
1539 }
1540 return addr;
1541 }
1542 case Op_ShenandoahLoadReferenceBarrier:
1543 return get_load_addr(phase, visited, in->in(ShenandoahLoadReferenceBarrierNode::ValueIn));
1544 case Op_ShenandoahEnqueueBarrier:
1545 return get_load_addr(phase, visited, in->in(1));
1546 case Op_CallDynamicJava:
1547 case Op_CallLeaf:
1548 case Op_CallStaticJava:
1549 case Op_ConN:
1550 case Op_ConP:
1551 case Op_Parm:
1552 case Op_CreateEx:
1553 return phase->igvn().zerocon(T_OBJECT);
1554 default:
1555 #ifdef ASSERT
1556 fatal("Unknown node in get_load_addr: %s", NodeClassNames[in->Opcode()]);
1557 #endif
1558 return phase->igvn().zerocon(T_OBJECT);
1559 }
1560
1561 }
1562
1563 void ShenandoahBarrierC2Support::move_gc_state_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase) {
1564 IdealLoopTree *loop = phase->get_loop(iff);
1565 Node* loop_head = loop->_head;
1566 Node* entry_c = loop_head->in(LoopNode::EntryControl);
1567
1568 Node* bol = iff->in(1);
1569 Node* cmp = bol->in(1);
1570 Node* andi = cmp->in(1);
1571 Node* load = andi->in(1);
1572
1573 assert(is_gc_state_load(load), "broken");
1574 if (!phase->is_dominator(load->in(0), entry_c)) {
1575 Node* mem_ctrl = NULL;
1576 Node* mem = dom_mem(load->in(MemNode::Memory), loop_head, Compile::AliasIdxRaw, mem_ctrl, phase);
1577 load = load->clone();
1578 load->set_req(MemNode::Memory, mem);
1579 load->set_req(0, entry_c);
1580 phase->register_new_node(load, entry_c);
1581 andi = andi->clone();
1582 andi->set_req(1, load);
1583 phase->register_new_node(andi, entry_c);
1584 cmp = cmp->clone();
1585 cmp->set_req(1, andi);
1586 phase->register_new_node(cmp, entry_c);
1587 bol = bol->clone();
1588 bol->set_req(1, cmp);
1589 phase->register_new_node(bol, entry_c);
1590
1591 Node* old_bol =iff->in(1);
1592 phase->igvn().replace_input_of(iff, 1, bol);
1593 }
1594 }
1595
1596 bool ShenandoahBarrierC2Support::identical_backtoback_ifs(Node* n, PhaseIdealLoop* phase) {
1597 if (!n->is_If() || n->is_CountedLoopEnd()) {
1598 return false;
1599 }
1600 Node* region = n->in(0);
1601
1602 if (!region->is_Region()) {
1603 return false;
1604 }
1605 Node* dom = phase->idom(region);
1606 if (!dom->is_If()) {
1607 return false;
1608 }
1609
1610 if (!is_heap_stable_test(n) || !is_heap_stable_test(dom)) {
1611 return false;
1612 }
1613
1614 IfNode* dom_if = dom->as_If();
1615 Node* proj_true = dom_if->proj_out(1);
1616 Node* proj_false = dom_if->proj_out(0);
1617
1618 for (uint i = 1; i < region->req(); i++) {
1619 if (phase->is_dominator(proj_true, region->in(i))) {
1620 continue;
1621 }
1622 if (phase->is_dominator(proj_false, region->in(i))) {
1623 continue;
1624 }
1625 return false;
1626 }
1627
1628 return true;
1629 }
1630
1631 void ShenandoahBarrierC2Support::merge_back_to_back_tests(Node* n, PhaseIdealLoop* phase) {
1632 assert(is_heap_stable_test(n), "no other tests");
1633 if (identical_backtoback_ifs(n, phase)) {
1634 Node* n_ctrl = n->in(0);
1635 if (phase->can_split_if(n_ctrl)) {
1636 IfNode* dom_if = phase->idom(n_ctrl)->as_If();
1637 if (is_heap_stable_test(n)) {
1638 Node* gc_state_load = n->in(1)->in(1)->in(1)->in(1);
1639 assert(is_gc_state_load(gc_state_load), "broken");
1640 Node* dom_gc_state_load = dom_if->in(1)->in(1)->in(1)->in(1);
1641 assert(is_gc_state_load(dom_gc_state_load), "broken");
1642 if (gc_state_load != dom_gc_state_load) {
1643 phase->igvn().replace_node(gc_state_load, dom_gc_state_load);
1644 }
1645 }
1646 PhiNode* bolphi = PhiNode::make_blank(n_ctrl, n->in(1));
1647 Node* proj_true = dom_if->proj_out(1);
1648 Node* proj_false = dom_if->proj_out(0);
1649 Node* con_true = phase->igvn().makecon(TypeInt::ONE);
1650 Node* con_false = phase->igvn().makecon(TypeInt::ZERO);
1651
1652 for (uint i = 1; i < n_ctrl->req(); i++) {
1653 if (phase->is_dominator(proj_true, n_ctrl->in(i))) {
1654 bolphi->init_req(i, con_true);
1655 } else {
1656 assert(phase->is_dominator(proj_false, n_ctrl->in(i)), "bad if");
1657 bolphi->init_req(i, con_false);
1658 }
1659 }
1660 phase->register_new_node(bolphi, n_ctrl);
1661 phase->igvn().replace_input_of(n, 1, bolphi);
1662 phase->do_split_if(n);
1663 }
1664 }
1665 }
1666
1667 IfNode* ShenandoahBarrierC2Support::find_unswitching_candidate(const IdealLoopTree* loop, PhaseIdealLoop* phase) {
1668 // Find first invariant test that doesn't exit the loop
1669 LoopNode *head = loop->_head->as_Loop();
1670 IfNode* unswitch_iff = NULL;
1671 Node* n = head->in(LoopNode::LoopBackControl);
1672 int loop_has_sfpts = -1;
1673 while (n != head) {
1674 Node* n_dom = phase->idom(n);
1675 if (n->is_Region()) {
1676 if (n_dom->is_If()) {
1677 IfNode* iff = n_dom->as_If();
1678 if (iff->in(1)->is_Bool()) {
1679 BoolNode* bol = iff->in(1)->as_Bool();
1680 if (bol->in(1)->is_Cmp()) {
1681 // If condition is invariant and not a loop exit,
1682 // then found reason to unswitch.
1683 if (is_heap_stable_test(iff) &&
1684 (loop_has_sfpts == -1 || loop_has_sfpts == 0)) {
1685 assert(!loop->is_loop_exit(iff), "both branches should be in the loop");
1686 if (loop_has_sfpts == -1) {
1687 for(uint i = 0; i < loop->_body.size(); i++) {
1688 Node *m = loop->_body[i];
1689 if (m->is_SafePoint() && !m->is_CallLeaf()) {
1690 loop_has_sfpts = 1;
1691 break;
1692 }
1693 }
1694 if (loop_has_sfpts == -1) {
1695 loop_has_sfpts = 0;
1696 }
1697 }
1698 if (!loop_has_sfpts) {
1699 unswitch_iff = iff;
1700 }
1701 }
1702 }
1703 }
1704 }
1705 }
1706 n = n_dom;
1707 }
1708 return unswitch_iff;
1709 }
1710
1711
1712 void ShenandoahBarrierC2Support::optimize_after_expansion(VectorSet &visited, Node_Stack &stack, Node_List &old_new, PhaseIdealLoop* phase) {
1713 Node_List heap_stable_tests;
1714 stack.push(phase->C->start(), 0);
1715 do {
1716 Node* n = stack.node();
1717 uint i = stack.index();
1718
1719 if (i < n->outcnt()) {
1720 Node* u = n->raw_out(i);
1721 stack.set_index(i+1);
1722 if (!visited.test_set(u->_idx)) {
1723 stack.push(u, 0);
1724 }
1725 } else {
1726 stack.pop();
1727 if (n->is_If() && is_heap_stable_test(n)) {
1728 heap_stable_tests.push(n);
1729 }
1730 }
1731 } while (stack.size() > 0);
1732
1733 for (uint i = 0; i < heap_stable_tests.size(); i++) {
1734 Node* n = heap_stable_tests.at(i);
1735 assert(is_heap_stable_test(n), "only evacuation test");
1736 merge_back_to_back_tests(n, phase);
1737 }
1738
1739 if (!phase->C->major_progress()) {
1740 VectorSet seen(Thread::current()->resource_area());
1741 for (uint i = 0; i < heap_stable_tests.size(); i++) {
1742 Node* n = heap_stable_tests.at(i);
1743 IdealLoopTree* loop = phase->get_loop(n);
1744 if (loop != phase->ltree_root() &&
1745 loop->_child == NULL &&
1746 !loop->_irreducible) {
1747 Node* head = loop->_head;
1748 if (head->is_Loop() &&
1749 (!head->is_CountedLoop() || head->as_CountedLoop()->is_main_loop() || head->as_CountedLoop()->is_normal_loop()) &&
1750 !seen.test_set(head->_idx)) {
1751 IfNode* iff = find_unswitching_candidate(loop, phase);
1752 if (iff != NULL) {
1753 Node* bol = iff->in(1);
1754 if (head->as_Loop()->is_strip_mined()) {
1755 head->as_Loop()->verify_strip_mined(0);
1756 }
1757 move_gc_state_test_out_of_loop(iff, phase);
1758
1759 AutoNodeBudget node_budget(phase);
1760
1761 if (loop->policy_unswitching(phase)) {
1762 if (head->as_Loop()->is_strip_mined()) {
1763 OuterStripMinedLoopNode* outer = head->as_CountedLoop()->outer_loop();
1764 hide_strip_mined_loop(outer, head->as_CountedLoop(), phase);
1765 }
1766 phase->do_unswitching(loop, old_new);
1767 } else {
1768 // Not proceeding with unswitching. Move load back in
1769 // the loop.
1770 phase->igvn().replace_input_of(iff, 1, bol);
1771 }
1772 }
1773 }
1774 }
1775 }
1776 }
1777 }
1778
1779 #ifdef ASSERT
1780 void ShenandoahBarrierC2Support::verify_raw_mem(RootNode* root) {
1781 const bool trace = false;
1782 ResourceMark rm;
1783 Unique_Node_List nodes;
1784 Unique_Node_List controls;
1785 Unique_Node_List memories;
1786
1787 nodes.push(root);
1788 for (uint next = 0; next < nodes.size(); next++) {
1789 Node *n = nodes.at(next);
1790 if (ShenandoahBarrierSetC2::is_shenandoah_lrb_call(n)) {
1791 controls.push(n);
1792 if (trace) { tty->print("XXXXXX verifying"); n->dump(); }
1793 for (uint next2 = 0; next2 < controls.size(); next2++) {
1794 Node *m = controls.at(next2);
1795 for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
1796 Node* u = m->fast_out(i);
1797 if (u->is_CFG() && !u->is_Root() &&
1798 !(u->Opcode() == Op_CProj && u->in(0)->Opcode() == Op_NeverBranch && u->as_Proj()->_con == 1) &&
1799 !(u->is_Region() && u->unique_ctrl_out()->Opcode() == Op_Halt)) {
1800 if (trace) { tty->print("XXXXXX pushing control"); u->dump(); }
1801 controls.push(u);
1802 }
1803 }
1804 }
1805 memories.push(n->as_Call()->proj_out(TypeFunc::Memory));
1806 for (uint next2 = 0; next2 < memories.size(); next2++) {
1807 Node *m = memories.at(next2);
1808 assert(m->bottom_type() == Type::MEMORY, "");
1809 for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
1810 Node* u = m->fast_out(i);
1811 if (u->bottom_type() == Type::MEMORY && (u->is_Mem() || u->is_ClearArray())) {
1812 if (trace) { tty->print("XXXXXX pushing memory"); u->dump(); }
1813 memories.push(u);
1814 } else if (u->is_LoadStore()) {
1815 if (trace) { tty->print("XXXXXX pushing memory"); u->find_out_with(Op_SCMemProj)->dump(); }
1816 memories.push(u->find_out_with(Op_SCMemProj));
1817 } else if (u->is_MergeMem() && u->as_MergeMem()->memory_at(Compile::AliasIdxRaw) == m) {
1818 if (trace) { tty->print("XXXXXX pushing memory"); u->dump(); }
1819 memories.push(u);
1820 } else if (u->is_Phi()) {
1821 assert(u->bottom_type() == Type::MEMORY, "");
1822 if (u->adr_type() == TypeRawPtr::BOTTOM || u->adr_type() == TypePtr::BOTTOM) {
1823 assert(controls.member(u->in(0)), "");
1824 if (trace) { tty->print("XXXXXX pushing memory"); u->dump(); }
1825 memories.push(u);
1826 }
1827 } else if (u->is_SafePoint() || u->is_MemBar()) {
1828 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
1829 Node* uu = u->fast_out(j);
1830 if (uu->bottom_type() == Type::MEMORY) {
1831 if (trace) { tty->print("XXXXXX pushing memory"); uu->dump(); }
1832 memories.push(uu);
1833 }
1834 }
1835 }
1836 }
1837 }
1838 for (uint next2 = 0; next2 < controls.size(); next2++) {
1839 Node *m = controls.at(next2);
1840 if (m->is_Region()) {
1841 bool all_in = true;
1842 for (uint i = 1; i < m->req(); i++) {
1843 if (!controls.member(m->in(i))) {
1844 all_in = false;
1845 break;
1846 }
1847 }
1848 if (trace) { tty->print("XXX verifying %s", all_in ? "all in" : ""); m->dump(); }
1849 bool found_phi = false;
1850 for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax && !found_phi; j++) {
1851 Node* u = m->fast_out(j);
1852 if (u->is_Phi() && memories.member(u)) {
1853 found_phi = true;
1854 for (uint i = 1; i < u->req() && found_phi; i++) {
1855 Node* k = u->in(i);
1856 if (memories.member(k) != controls.member(m->in(i))) {
1857 found_phi = false;
1858 }
1859 }
1860 }
1861 }
1862 assert(found_phi || all_in, "");
1863 }
1864 }
1865 controls.clear();
1866 memories.clear();
1867 }
1868 for( uint i = 0; i < n->len(); ++i ) {
1869 Node *m = n->in(i);
1870 if (m != NULL) {
1871 nodes.push(m);
1872 }
1873 }
1874 }
1875 }
1876 #endif
1877
1878 ShenandoahEnqueueBarrierNode::ShenandoahEnqueueBarrierNode(Node* val) : Node(NULL, val) {
1879 ShenandoahBarrierSetC2::bsc2()->state()->add_enqueue_barrier(this);
1880 }
1881
1882 const Type* ShenandoahEnqueueBarrierNode::bottom_type() const {
1883 if (in(1) == NULL || in(1)->is_top()) {
1884 return Type::TOP;
1885 }
1886 const Type* t = in(1)->bottom_type();
1887 if (t == TypePtr::NULL_PTR) {
1888 return t;
1889 }
1890 return t->is_oopptr();
1891 }
1892
1893 const Type* ShenandoahEnqueueBarrierNode::Value(PhaseGVN* phase) const {
1894 if (in(1) == NULL) {
1895 return Type::TOP;
1896 }
1897 const Type* t = phase->type(in(1));
1898 if (t == Type::TOP) {
1899 return Type::TOP;
1900 }
1901 if (t == TypePtr::NULL_PTR) {
1902 return t;
1903 }
1904 return t->is_oopptr();
1905 }
1906
1907 int ShenandoahEnqueueBarrierNode::needed(Node* n) {
1908 if (n == NULL ||
1909 n->is_Allocate() ||
1910 n->Opcode() == Op_ShenandoahEnqueueBarrier ||
1911 n->bottom_type() == TypePtr::NULL_PTR ||
1912 (n->bottom_type()->make_oopptr() != NULL && n->bottom_type()->make_oopptr()->const_oop() != NULL)) {
1913 return NotNeeded;
1914 }
1915 if (n->is_Phi() ||
1916 n->is_CMove()) {
1917 return MaybeNeeded;
1918 }
1919 return Needed;
1920 }
1921
1922 Node* ShenandoahEnqueueBarrierNode::next(Node* n) {
1923 for (;;) {
1924 if (n == NULL) {
1925 return n;
1926 } else if (n->bottom_type() == TypePtr::NULL_PTR) {
1927 return n;
1928 } else if (n->bottom_type()->make_oopptr() != NULL && n->bottom_type()->make_oopptr()->const_oop() != NULL) {
1929 return n;
1930 } else if (n->is_ConstraintCast() ||
1931 n->Opcode() == Op_DecodeN ||
1932 n->Opcode() == Op_EncodeP) {
1933 n = n->in(1);
1934 } else if (n->is_Proj()) {
1935 n = n->in(0);
1936 } else {
1937 return n;
1938 }
1939 }
1940 ShouldNotReachHere();
1941 return NULL;
1942 }
1943
1944 Node* ShenandoahEnqueueBarrierNode::Identity(PhaseGVN* phase) {
1945 PhaseIterGVN* igvn = phase->is_IterGVN();
1946
1947 Node* n = next(in(1));
1948
1949 int cont = needed(n);
1950
1951 if (cont == NotNeeded) {
1952 return in(1);
1953 } else if (cont == MaybeNeeded) {
1954 if (igvn == NULL) {
1955 phase->record_for_igvn(this);
1956 return this;
1957 } else {
1958 ResourceMark rm;
1959 Unique_Node_List wq;
1960 uint wq_i = 0;
1961
1962 for (;;) {
1963 if (n->is_Phi()) {
1964 for (uint i = 1; i < n->req(); i++) {
1965 Node* m = n->in(i);
1966 if (m != NULL) {
1967 wq.push(m);
1968 }
1969 }
1970 } else {
1971 assert(n->is_CMove(), "nothing else here");
1972 Node* m = n->in(CMoveNode::IfFalse);
1973 wq.push(m);
1974 m = n->in(CMoveNode::IfTrue);
1975 wq.push(m);
1976 }
1977 Node* orig_n = NULL;
1978 do {
1979 if (wq_i >= wq.size()) {
1980 return in(1);
1981 }
1982 n = wq.at(wq_i);
1983 wq_i++;
1984 orig_n = n;
1985 n = next(n);
1986 cont = needed(n);
1987 if (cont == Needed) {
1988 return this;
1989 }
1990 } while (cont != MaybeNeeded || (orig_n != n && wq.member(n)));
1991 }
1992 }
1993 }
1994
1995 return this;
1996 }
1997
1998 #ifdef ASSERT
1999 static bool has_never_branch(Node* root) {
2000 for (uint i = 1; i < root->req(); i++) {
2001 Node* in = root->in(i);
2002 if (in != NULL && in->Opcode() == Op_Halt && in->in(0)->is_Proj() && in->in(0)->in(0)->Opcode() == Op_NeverBranch) {
2003 return true;
2004 }
2005 }
2006 return false;
2007 }
2008 #endif
2009
2010 void MemoryGraphFixer::collect_memory_nodes() {
2011 Node_Stack stack(0);
2012 VectorSet visited(Thread::current()->resource_area());
2013 Node_List regions;
2014
2015 // Walk the raw memory graph and create a mapping from CFG node to
2016 // memory node. Exclude phis for now.
2017 stack.push(_phase->C->root(), 1);
2018 do {
2019 Node* n = stack.node();
2020 int opc = n->Opcode();
2021 uint i = stack.index();
2022 if (i < n->req()) {
2023 Node* mem = NULL;
2024 if (opc == Op_Root) {
2025 Node* in = n->in(i);
2026 int in_opc = in->Opcode();
2027 if (in_opc == Op_Return || in_opc == Op_Rethrow) {
2028 mem = in->in(TypeFunc::Memory);
2029 } else if (in_opc == Op_Halt) {
2030 if (in->in(0)->is_Region()) {
2031 Node* r = in->in(0);
2032 for (uint j = 1; j < r->req(); j++) {
2033 assert(r->in(j)->Opcode() != Op_NeverBranch, "");
2034 }
2035 } else {
2036 Node* proj = in->in(0);
2037 assert(proj->is_Proj(), "");
2038 Node* in = proj->in(0);
2039 assert(in->is_CallStaticJava() || in->Opcode() == Op_NeverBranch || in->Opcode() == Op_Catch || proj->is_IfProj(), "");
2040 if (in->is_CallStaticJava()) {
2041 mem = in->in(TypeFunc::Memory);
2042 } else if (in->Opcode() == Op_Catch) {
2043 Node* call = in->in(0)->in(0);
2044 assert(call->is_Call(), "");
2045 mem = call->in(TypeFunc::Memory);
2046 } else if (in->Opcode() == Op_NeverBranch) {
2047 Node* head = in->in(0);
2048 assert(head->is_Region() && head->req() == 3, "unexpected infinite loop graph shape");
2049 assert(_phase->is_dominator(head, head->in(1)) || _phase->is_dominator(head, head->in(2)), "no back branch?");
2050 Node* tail = _phase->is_dominator(head, head->in(1)) ? head->in(1) : head->in(2);
2051 Node* c = tail;
2052 while (c != head) {
2053 if (c->is_SafePoint() && !c->is_CallLeaf()) {
2054 mem = c->in(TypeFunc::Memory);
2055 }
2056 c = _phase->idom(c);
2057 }
2058 assert(mem != NULL, "should have found safepoint");
2059
2060 Node* phi_mem = NULL;
2061 for (DUIterator_Fast jmax, j = head->fast_outs(jmax); j < jmax; j++) {
2062 Node* u = head->fast_out(j);
2063 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
2064 if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2065 assert(phi_mem == NULL || phi_mem->adr_type() == TypePtr::BOTTOM, "");
2066 phi_mem = u;
2067 } else if (u->adr_type() == TypePtr::BOTTOM) {
2068 assert(phi_mem == NULL || _phase->C->get_alias_index(phi_mem->adr_type()) == _alias, "");
2069 if (phi_mem == NULL) {
2070 phi_mem = u;
2071 }
2072 }
2073 }
2074 }
2075 if (phi_mem != NULL) {
2076 mem = phi_mem;
2077 }
2078 }
2079 }
2080 } else {
2081 #ifdef ASSERT
2082 n->dump();
2083 in->dump();
2084 #endif
2085 ShouldNotReachHere();
2086 }
2087 } else {
2088 assert(n->is_Phi() && n->bottom_type() == Type::MEMORY, "");
2089 assert(n->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(n->adr_type()) == _alias, "");
2090 mem = n->in(i);
2091 }
2092 i++;
2093 stack.set_index(i);
2094 if (mem == NULL) {
2095 continue;
2096 }
2097 for (;;) {
2098 if (visited.test_set(mem->_idx) || mem->is_Start()) {
2099 break;
2100 }
2101 if (mem->is_Phi()) {
2102 stack.push(mem, 2);
2103 mem = mem->in(1);
2104 } else if (mem->is_Proj()) {
2105 stack.push(mem, mem->req());
2106 mem = mem->in(0);
2107 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
2108 mem = mem->in(TypeFunc::Memory);
2109 } else if (mem->is_MergeMem()) {
2110 MergeMemNode* mm = mem->as_MergeMem();
2111 mem = mm->memory_at(_alias);
2112 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
2113 assert(_alias == Compile::AliasIdxRaw, "");
2114 stack.push(mem, mem->req());
2115 mem = mem->in(MemNode::Memory);
2116 } else {
2117 #ifdef ASSERT
2118 mem->dump();
2119 #endif
2120 ShouldNotReachHere();
2121 }
2122 }
2123 } else {
2124 if (n->is_Phi()) {
2125 // Nothing
2126 } else if (!n->is_Root()) {
2127 Node* c = get_ctrl(n);
2128 _memory_nodes.map(c->_idx, n);
2129 }
2130 stack.pop();
2131 }
2132 } while(stack.is_nonempty());
2133
2134 // Iterate over CFG nodes in rpo and propagate memory state to
2135 // compute memory state at regions, creating new phis if needed.
2136 Node_List rpo_list;
2137 visited.clear();
2138 _phase->rpo(_phase->C->root(), stack, visited, rpo_list);
2139 Node* root = rpo_list.pop();
2140 assert(root == _phase->C->root(), "");
2141
2142 const bool trace = false;
2143 #ifdef ASSERT
2144 if (trace) {
2145 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2146 Node* c = rpo_list.at(i);
2147 if (_memory_nodes[c->_idx] != NULL) {
2148 tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump();
2149 }
2150 }
2151 }
2152 #endif
2153 uint last = _phase->C->unique();
2154
2155 #ifdef ASSERT
2156 uint8_t max_depth = 0;
2157 for (LoopTreeIterator iter(_phase->ltree_root()); !iter.done(); iter.next()) {
2158 IdealLoopTree* lpt = iter.current();
2159 max_depth = MAX2(max_depth, lpt->_nest);
2160 }
2161 #endif
2162
2163 bool progress = true;
2164 int iteration = 0;
2165 Node_List dead_phis;
2166 while (progress) {
2167 progress = false;
2168 iteration++;
2169 assert(iteration <= 2+max_depth || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "");
2170 if (trace) { tty->print_cr("XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"); }
2171 IdealLoopTree* last_updated_ilt = NULL;
2172 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2173 Node* c = rpo_list.at(i);
2174
2175 Node* prev_mem = _memory_nodes[c->_idx];
2176 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2177 Node* prev_region = regions[c->_idx];
2178 Node* unique = NULL;
2179 for (uint j = 1; j < c->req() && unique != NodeSentinel; j++) {
2180 Node* m = _memory_nodes[c->in(j)->_idx];
2181 assert(m != NULL || (c->is_Loop() && j == LoopNode::LoopBackControl && iteration == 1) || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "expect memory state");
2182 if (m != NULL) {
2183 if (m == prev_region && ((c->is_Loop() && j == LoopNode::LoopBackControl) || (prev_region->is_Phi() && prev_region->in(0) == c))) {
2184 assert(c->is_Loop() && j == LoopNode::LoopBackControl || _phase->C->has_irreducible_loop(), "");
2185 // continue
2186 } else if (unique == NULL) {
2187 unique = m;
2188 } else if (m == unique) {
2189 // continue
2190 } else {
2191 unique = NodeSentinel;
2192 }
2193 }
2194 }
2195 assert(unique != NULL, "empty phi???");
2196 if (unique != NodeSentinel) {
2197 if (prev_region != NULL && prev_region->is_Phi() && prev_region->in(0) == c) {
2198 dead_phis.push(prev_region);
2199 }
2200 regions.map(c->_idx, unique);
2201 } else {
2202 Node* phi = NULL;
2203 if (prev_region != NULL && prev_region->is_Phi() && prev_region->in(0) == c && prev_region->_idx >= last) {
2204 phi = prev_region;
2205 for (uint k = 1; k < c->req(); k++) {
2206 Node* m = _memory_nodes[c->in(k)->_idx];
2207 assert(m != NULL, "expect memory state");
2208 phi->set_req(k, m);
2209 }
2210 } else {
2211 for (DUIterator_Fast jmax, j = c->fast_outs(jmax); j < jmax && phi == NULL; j++) {
2212 Node* u = c->fast_out(j);
2213 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2214 (u->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(u->adr_type()) == _alias)) {
2215 phi = u;
2216 for (uint k = 1; k < c->req() && phi != NULL; k++) {
2217 Node* m = _memory_nodes[c->in(k)->_idx];
2218 assert(m != NULL, "expect memory state");
2219 if (u->in(k) != m) {
2220 phi = NULL;
2221 }
2222 }
2223 }
2224 }
2225 if (phi == NULL) {
2226 phi = new PhiNode(c, Type::MEMORY, _phase->C->get_adr_type(_alias));
2227 for (uint k = 1; k < c->req(); k++) {
2228 Node* m = _memory_nodes[c->in(k)->_idx];
2229 assert(m != NULL, "expect memory state");
2230 phi->init_req(k, m);
2231 }
2232 }
2233 }
2234 assert(phi != NULL, "");
2235 regions.map(c->_idx, phi);
2236 }
2237 Node* current_region = regions[c->_idx];
2238 if (current_region != prev_region) {
2239 progress = true;
2240 if (prev_region == prev_mem) {
2241 _memory_nodes.map(c->_idx, current_region);
2242 }
2243 }
2244 } else if (prev_mem == NULL || prev_mem->is_Phi() || ctrl_or_self(prev_mem) != c) {
2245 Node* m = _memory_nodes[_phase->idom(c)->_idx];
2246 assert(m != NULL, "expect memory state");
2247 if (m != prev_mem) {
2248 _memory_nodes.map(c->_idx, m);
2249 progress = true;
2250 }
2251 }
2252 #ifdef ASSERT
2253 if (trace) { tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump(); }
2254 #endif
2255 }
2256 }
2257
2258 // Replace existing phi with computed memory state for that region
2259 // if different (could be a new phi or a dominating memory node if
2260 // that phi was found to be useless).
2261 while (dead_phis.size() > 0) {
2262 Node* n = dead_phis.pop();
2263 n->replace_by(_phase->C->top());
2264 n->destruct();
2265 }
2266 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2267 Node* c = rpo_list.at(i);
2268 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2269 Node* n = regions[c->_idx];
2270 if (n->is_Phi() && n->_idx >= last && n->in(0) == c) {
2271 _phase->register_new_node(n, c);
2272 }
2273 }
2274 }
2275 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2276 Node* c = rpo_list.at(i);
2277 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2278 Node* n = regions[c->_idx];
2279 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
2280 Node* u = c->fast_out(i);
2281 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2282 u != n) {
2283 if (u->adr_type() == TypePtr::BOTTOM) {
2284 fix_memory_uses(u, n, n, c);
2285 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2286 _phase->lazy_replace(u, n);
2287 --i; --imax;
2288 }
2289 }
2290 }
2291 }
2292 }
2293 }
2294
2295 Node* MemoryGraphFixer::get_ctrl(Node* n) const {
2296 Node* c = _phase->get_ctrl(n);
2297 if (n->is_Proj() && n->in(0) != NULL && n->in(0)->is_Call()) {
2298 assert(c == n->in(0), "");
2299 CallNode* call = c->as_Call();
2300 CallProjections projs;
2301 call->extract_projections(&projs, true, false);
2302 if (projs.catchall_memproj != NULL) {
2303 if (projs.fallthrough_memproj == n) {
2304 c = projs.fallthrough_catchproj;
2305 } else {
2306 assert(projs.catchall_memproj == n, "");
2307 c = projs.catchall_catchproj;
2308 }
2309 }
2310 }
2311 return c;
2312 }
2313
2314 Node* MemoryGraphFixer::ctrl_or_self(Node* n) const {
2315 if (_phase->has_ctrl(n))
2316 return get_ctrl(n);
2317 else {
2318 assert (n->is_CFG(), "must be a CFG node");
2319 return n;
2320 }
2321 }
2322
2323 bool MemoryGraphFixer::mem_is_valid(Node* m, Node* c) const {
2324 return m != NULL && get_ctrl(m) == c;
2325 }
2326
2327 Node* MemoryGraphFixer::find_mem(Node* ctrl, Node* n) const {
2328 assert(n == NULL || _phase->ctrl_or_self(n) == ctrl, "");
2329 Node* mem = _memory_nodes[ctrl->_idx];
2330 Node* c = ctrl;
2331 while (!mem_is_valid(mem, c) &&
2332 (!c->is_CatchProj() || mem == NULL || c->in(0)->in(0)->in(0) != get_ctrl(mem))) {
2333 c = _phase->idom(c);
2334 mem = _memory_nodes[c->_idx];
2335 }
2336 if (n != NULL && mem_is_valid(mem, c)) {
2337 while (!ShenandoahBarrierC2Support::is_dominator_same_ctrl(c, mem, n, _phase) && _phase->ctrl_or_self(mem) == ctrl) {
2338 mem = next_mem(mem, _alias);
2339 }
2340 if (mem->is_MergeMem()) {
2341 mem = mem->as_MergeMem()->memory_at(_alias);
2342 }
2343 if (!mem_is_valid(mem, c)) {
2344 do {
2345 c = _phase->idom(c);
2346 mem = _memory_nodes[c->_idx];
2347 } while (!mem_is_valid(mem, c) &&
2348 (!c->is_CatchProj() || mem == NULL || c->in(0)->in(0)->in(0) != get_ctrl(mem)));
2349 }
2350 }
2351 assert(mem->bottom_type() == Type::MEMORY, "");
2352 return mem;
2353 }
2354
2355 bool MemoryGraphFixer::has_mem_phi(Node* region) const {
2356 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
2357 Node* use = region->fast_out(i);
2358 if (use->is_Phi() && use->bottom_type() == Type::MEMORY &&
2359 (_phase->C->get_alias_index(use->adr_type()) == _alias)) {
2360 return true;
2361 }
2362 }
2363 return false;
2364 }
2365
2366 void MemoryGraphFixer::fix_mem(Node* ctrl, Node* new_ctrl, Node* mem, Node* mem_for_ctrl, Node* new_mem, Unique_Node_List& uses) {
2367 assert(_phase->ctrl_or_self(new_mem) == new_ctrl, "");
2368 const bool trace = false;
2369 DEBUG_ONLY(if (trace) { tty->print("ZZZ control is"); ctrl->dump(); });
2370 DEBUG_ONLY(if (trace) { tty->print("ZZZ mem is"); mem->dump(); });
2371 GrowableArray<Node*> phis;
2372 if (mem_for_ctrl != mem) {
2373 Node* old = mem_for_ctrl;
2374 Node* prev = NULL;
2375 while (old != mem) {
2376 prev = old;
2377 if (old->is_Store() || old->is_ClearArray() || old->is_LoadStore()) {
2378 assert(_alias == Compile::AliasIdxRaw, "");
2379 old = old->in(MemNode::Memory);
2380 } else if (old->Opcode() == Op_SCMemProj) {
2381 assert(_alias == Compile::AliasIdxRaw, "");
2382 old = old->in(0);
2383 } else {
2384 ShouldNotReachHere();
2385 }
2386 }
2387 assert(prev != NULL, "");
2388 if (new_ctrl != ctrl) {
2389 _memory_nodes.map(ctrl->_idx, mem);
2390 _memory_nodes.map(new_ctrl->_idx, mem_for_ctrl);
2391 }
2392 uint input = (uint)MemNode::Memory;
2393 _phase->igvn().replace_input_of(prev, input, new_mem);
2394 } else {
2395 uses.clear();
2396 _memory_nodes.map(new_ctrl->_idx, new_mem);
2397 uses.push(new_ctrl);
2398 for(uint next = 0; next < uses.size(); next++ ) {
2399 Node *n = uses.at(next);
2400 assert(n->is_CFG(), "");
2401 DEBUG_ONLY(if (trace) { tty->print("ZZZ ctrl"); n->dump(); });
2402 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2403 Node* u = n->fast_out(i);
2404 if (!u->is_Root() && u->is_CFG() && u != n) {
2405 Node* m = _memory_nodes[u->_idx];
2406 if (u->is_Region() && (!u->is_OuterStripMinedLoop() || _include_lsm) &&
2407 !has_mem_phi(u) &&
2408 u->unique_ctrl_out()->Opcode() != Op_Halt) {
2409 DEBUG_ONLY(if (trace) { tty->print("ZZZ region"); u->dump(); });
2410 DEBUG_ONLY(if (trace && m != NULL) { tty->print("ZZZ mem"); m->dump(); });
2411
2412 if (!mem_is_valid(m, u) || !m->is_Phi()) {
2413 bool push = true;
2414 bool create_phi = true;
2415 if (_phase->is_dominator(new_ctrl, u)) {
2416 create_phi = false;
2417 }
2418 if (create_phi) {
2419 Node* phi = new PhiNode(u, Type::MEMORY, _phase->C->get_adr_type(_alias));
2420 _phase->register_new_node(phi, u);
2421 phis.push(phi);
2422 DEBUG_ONLY(if (trace) { tty->print("ZZZ new phi"); phi->dump(); });
2423 if (!mem_is_valid(m, u)) {
2424 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting mem"); phi->dump(); });
2425 _memory_nodes.map(u->_idx, phi);
2426 } else {
2427 DEBUG_ONLY(if (trace) { tty->print("ZZZ NOT setting mem"); m->dump(); });
2428 for (;;) {
2429 assert(m->is_Mem() || m->is_LoadStore() || m->is_Proj(), "");
2430 Node* next = NULL;
2431 if (m->is_Proj()) {
2432 next = m->in(0);
2433 } else {
2434 assert(m->is_Mem() || m->is_LoadStore(), "");
2435 assert(_alias == Compile::AliasIdxRaw, "");
2436 next = m->in(MemNode::Memory);
2437 }
2438 if (_phase->get_ctrl(next) != u) {
2439 break;
2440 }
2441 if (next->is_MergeMem()) {
2442 assert(_phase->get_ctrl(next->as_MergeMem()->memory_at(_alias)) != u, "");
2443 break;
2444 }
2445 if (next->is_Phi()) {
2446 assert(next->adr_type() == TypePtr::BOTTOM && next->in(0) == u, "");
2447 break;
2448 }
2449 m = next;
2450 }
2451
2452 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting to phi"); m->dump(); });
2453 assert(m->is_Mem() || m->is_LoadStore(), "");
2454 uint input = (uint)MemNode::Memory;
2455 _phase->igvn().replace_input_of(m, input, phi);
2456 push = false;
2457 }
2458 } else {
2459 DEBUG_ONLY(if (trace) { tty->print("ZZZ skipping region"); u->dump(); });
2460 }
2461 if (push) {
2462 uses.push(u);
2463 }
2464 }
2465 } else if (!mem_is_valid(m, u) &&
2466 !(u->Opcode() == Op_CProj && u->in(0)->Opcode() == Op_NeverBranch && u->as_Proj()->_con == 1)) {
2467 uses.push(u);
2468 }
2469 }
2470 }
2471 }
2472 for (int i = 0; i < phis.length(); i++) {
2473 Node* n = phis.at(i);
2474 Node* r = n->in(0);
2475 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi"); n->dump(); });
2476 for (uint j = 1; j < n->req(); j++) {
2477 Node* m = find_mem(r->in(j), NULL);
2478 _phase->igvn().replace_input_of(n, j, m);
2479 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi: %d", j); m->dump(); });
2480 }
2481 }
2482 }
2483 uint last = _phase->C->unique();
2484 MergeMemNode* mm = NULL;
2485 int alias = _alias;
2486 DEBUG_ONLY(if (trace) { tty->print("ZZZ raw mem is"); mem->dump(); });
2487 // Process loads first to not miss an anti-dependency: if the memory
2488 // edge of a store is updated before a load is processed then an
2489 // anti-dependency may be missed.
2490 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2491 Node* u = mem->out(i);
2492 if (u->_idx < last && u->is_Load() && _phase->C->get_alias_index(u->adr_type()) == alias) {
2493 Node* m = find_mem(_phase->get_ctrl(u), u);
2494 if (m != mem) {
2495 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2496 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2497 --i;
2498 }
2499 }
2500 }
2501 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2502 Node* u = mem->out(i);
2503 if (u->_idx < last) {
2504 if (u->is_Mem()) {
2505 if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2506 Node* m = find_mem(_phase->get_ctrl(u), u);
2507 if (m != mem) {
2508 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2509 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2510 --i;
2511 }
2512 }
2513 } else if (u->is_MergeMem()) {
2514 MergeMemNode* u_mm = u->as_MergeMem();
2515 if (u_mm->memory_at(alias) == mem) {
2516 MergeMemNode* newmm = NULL;
2517 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2518 Node* uu = u->fast_out(j);
2519 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2520 if (uu->is_Phi()) {
2521 assert(uu->adr_type() == TypePtr::BOTTOM, "");
2522 Node* region = uu->in(0);
2523 int nb = 0;
2524 for (uint k = 1; k < uu->req(); k++) {
2525 if (uu->in(k) == u) {
2526 Node* m = find_mem(region->in(k), NULL);
2527 if (m != mem) {
2528 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", k); uu->dump(); });
2529 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2530 if (newmm != u) {
2531 _phase->igvn().replace_input_of(uu, k, newmm);
2532 nb++;
2533 --jmax;
2534 }
2535 }
2536 }
2537 }
2538 if (nb > 0) {
2539 --j;
2540 }
2541 } else {
2542 Node* m = find_mem(_phase->ctrl_or_self(uu), uu);
2543 if (m != mem) {
2544 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); uu->dump(); });
2545 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2546 if (newmm != u) {
2547 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2548 --j, --jmax;
2549 }
2550 }
2551 }
2552 }
2553 }
2554 } else if (u->is_Phi()) {
2555 assert(u->bottom_type() == Type::MEMORY, "what else?");
2556 if (_phase->C->get_alias_index(u->adr_type()) == alias || u->adr_type() == TypePtr::BOTTOM) {
2557 Node* region = u->in(0);
2558 bool replaced = false;
2559 for (uint j = 1; j < u->req(); j++) {
2560 if (u->in(j) == mem) {
2561 Node* m = find_mem(region->in(j), NULL);
2562 Node* nnew = m;
2563 if (m != mem) {
2564 if (u->adr_type() == TypePtr::BOTTOM) {
2565 mm = allocate_merge_mem(mem, m, _phase->ctrl_or_self(m));
2566 nnew = mm;
2567 }
2568 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", j); u->dump(); });
2569 _phase->igvn().replace_input_of(u, j, nnew);
2570 replaced = true;
2571 }
2572 }
2573 }
2574 if (replaced) {
2575 --i;
2576 }
2577 }
2578 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2579 u->adr_type() == NULL) {
2580 assert(u->adr_type() != NULL ||
2581 u->Opcode() == Op_Rethrow ||
2582 u->Opcode() == Op_Return ||
2583 u->Opcode() == Op_SafePoint ||
2584 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2585 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2586 u->Opcode() == Op_CallLeaf, "");
2587 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2588 if (m != mem) {
2589 mm = allocate_merge_mem(mem, m, _phase->get_ctrl(m));
2590 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2591 --i;
2592 }
2593 } else if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2594 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2595 if (m != mem) {
2596 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2597 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2598 --i;
2599 }
2600 } else if (u->adr_type() != TypePtr::BOTTOM &&
2601 _memory_nodes[_phase->ctrl_or_self(u)->_idx] == u) {
2602 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2603 assert(m != mem, "");
2604 // u is on the wrong slice...
2605 assert(u->is_ClearArray(), "");
2606 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2607 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2608 --i;
2609 }
2610 }
2611 }
2612 #ifdef ASSERT
2613 assert(new_mem->outcnt() > 0, "");
2614 for (int i = 0; i < phis.length(); i++) {
2615 Node* n = phis.at(i);
2616 assert(n->outcnt() > 0, "new phi must have uses now");
2617 }
2618 #endif
2619 }
2620
2621 MergeMemNode* MemoryGraphFixer::allocate_merge_mem(Node* mem, Node* rep_proj, Node* rep_ctrl) const {
2622 MergeMemNode* mm = MergeMemNode::make(mem);
2623 mm->set_memory_at(_alias, rep_proj);
2624 _phase->register_new_node(mm, rep_ctrl);
2625 return mm;
2626 }
2627
2628 MergeMemNode* MemoryGraphFixer::clone_merge_mem(Node* u, Node* mem, Node* rep_proj, Node* rep_ctrl, DUIterator& i) const {
2629 MergeMemNode* newmm = NULL;
2630 MergeMemNode* u_mm = u->as_MergeMem();
2631 Node* c = _phase->get_ctrl(u);
2632 if (_phase->is_dominator(c, rep_ctrl)) {
2633 c = rep_ctrl;
2634 } else {
2635 assert(_phase->is_dominator(rep_ctrl, c), "one must dominate the other");
2636 }
2637 if (u->outcnt() == 1) {
2638 if (u->req() > (uint)_alias && u->in(_alias) == mem) {
2639 _phase->igvn().replace_input_of(u, _alias, rep_proj);
2640 --i;
2641 } else {
2642 _phase->igvn().rehash_node_delayed(u);
2643 u_mm->set_memory_at(_alias, rep_proj);
2644 }
2645 newmm = u_mm;
2646 _phase->set_ctrl_and_loop(u, c);
2647 } else {
2648 // can't simply clone u and then change one of its input because
2649 // it adds and then removes an edge which messes with the
2650 // DUIterator
2651 newmm = MergeMemNode::make(u_mm->base_memory());
2652 for (uint j = 0; j < u->req(); j++) {
2653 if (j < newmm->req()) {
2654 if (j == (uint)_alias) {
2655 newmm->set_req(j, rep_proj);
2656 } else if (newmm->in(j) != u->in(j)) {
2657 newmm->set_req(j, u->in(j));
2658 }
2659 } else if (j == (uint)_alias) {
2660 newmm->add_req(rep_proj);
2661 } else {
2662 newmm->add_req(u->in(j));
2663 }
2664 }
2665 if ((uint)_alias >= u->req()) {
2666 newmm->set_memory_at(_alias, rep_proj);
2667 }
2668 _phase->register_new_node(newmm, c);
2669 }
2670 return newmm;
2671 }
2672
2673 bool MemoryGraphFixer::should_process_phi(Node* phi) const {
2674 if (phi->adr_type() == TypePtr::BOTTOM) {
2675 Node* region = phi->in(0);
2676 for (DUIterator_Fast jmax, j = region->fast_outs(jmax); j < jmax; j++) {
2677 Node* uu = region->fast_out(j);
2678 if (uu->is_Phi() && uu != phi && uu->bottom_type() == Type::MEMORY && _phase->C->get_alias_index(uu->adr_type()) == _alias) {
2679 return false;
2680 }
2681 }
2682 return true;
2683 }
2684 return _phase->C->get_alias_index(phi->adr_type()) == _alias;
2685 }
2686
2687 void MemoryGraphFixer::fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl) const {
2688 uint last = _phase-> C->unique();
2689 MergeMemNode* mm = NULL;
2690 assert(mem->bottom_type() == Type::MEMORY, "");
2691 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2692 Node* u = mem->out(i);
2693 if (u != replacement && u->_idx < last) {
2694 if (u->is_MergeMem()) {
2695 MergeMemNode* u_mm = u->as_MergeMem();
2696 if (u_mm->memory_at(_alias) == mem) {
2697 MergeMemNode* newmm = NULL;
2698 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2699 Node* uu = u->fast_out(j);
2700 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2701 if (uu->is_Phi()) {
2702 if (should_process_phi(uu)) {
2703 Node* region = uu->in(0);
2704 int nb = 0;
2705 for (uint k = 1; k < uu->req(); k++) {
2706 if (uu->in(k) == u && _phase->is_dominator(rep_ctrl, region->in(k))) {
2707 if (newmm == NULL) {
2708 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2709 }
2710 if (newmm != u) {
2711 _phase->igvn().replace_input_of(uu, k, newmm);
2712 nb++;
2713 --jmax;
2714 }
2715 }
2716 }
2717 if (nb > 0) {
2718 --j;
2719 }
2720 }
2721 } else {
2722 if (rep_ctrl != uu && ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(uu), replacement, uu, _phase)) {
2723 if (newmm == NULL) {
2724 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2725 }
2726 if (newmm != u) {
2727 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2728 --j, --jmax;
2729 }
2730 }
2731 }
2732 }
2733 }
2734 } else if (u->is_Phi()) {
2735 assert(u->bottom_type() == Type::MEMORY, "what else?");
2736 Node* region = u->in(0);
2737 if (should_process_phi(u)) {
2738 bool replaced = false;
2739 for (uint j = 1; j < u->req(); j++) {
2740 if (u->in(j) == mem && _phase->is_dominator(rep_ctrl, region->in(j))) {
2741 Node* nnew = rep_proj;
2742 if (u->adr_type() == TypePtr::BOTTOM) {
2743 if (mm == NULL) {
2744 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2745 }
2746 nnew = mm;
2747 }
2748 _phase->igvn().replace_input_of(u, j, nnew);
2749 replaced = true;
2750 }
2751 }
2752 if (replaced) {
2753 --i;
2754 }
2755
2756 }
2757 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2758 u->adr_type() == NULL) {
2759 assert(u->adr_type() != NULL ||
2760 u->Opcode() == Op_Rethrow ||
2761 u->Opcode() == Op_Return ||
2762 u->Opcode() == Op_SafePoint ||
2763 u->Opcode() == Op_StoreIConditional ||
2764 u->Opcode() == Op_StoreLConditional ||
2765 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2766 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2767 u->Opcode() == Op_CallLeaf, "%s", u->Name());
2768 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2769 if (mm == NULL) {
2770 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2771 }
2772 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2773 --i;
2774 }
2775 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2776 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2777 _phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
2778 --i;
2779 }
2780 }
2781 }
2782 }
2783 }
2784
2785 ShenandoahLoadReferenceBarrierNode::ShenandoahLoadReferenceBarrierNode(Node* ctrl, Node* obj, bool native)
2786 : Node(ctrl, obj), _native(native) {
2787 ShenandoahBarrierSetC2::bsc2()->state()->add_load_reference_barrier(this);
2788 }
2789
2790 bool ShenandoahLoadReferenceBarrierNode::is_native() const {
2791 return _native;
2792 }
2793
2794 uint ShenandoahLoadReferenceBarrierNode::size_of() const {
2795 return sizeof(*this);
2796 }
2797
2798 uint ShenandoahLoadReferenceBarrierNode::hash() const {
2799 return Node::hash() + (_native ? 1 : 0);
2800 }
2801
2802 bool ShenandoahLoadReferenceBarrierNode::cmp( const Node &n ) const {
2803 return Node::cmp(n) && n.Opcode() == Op_ShenandoahLoadReferenceBarrier &&
2804 _native == ((const ShenandoahLoadReferenceBarrierNode&)n)._native;
2805 }
2806
2807 const Type* ShenandoahLoadReferenceBarrierNode::bottom_type() const {
2808 if (in(ValueIn) == NULL || in(ValueIn)->is_top()) {
2809 return Type::TOP;
2810 }
2811 const Type* t = in(ValueIn)->bottom_type();
2812 if (t == TypePtr::NULL_PTR) {
2813 return t;
2814 }
2815 return t->is_oopptr();
2816 }
2817
2818 const Type* ShenandoahLoadReferenceBarrierNode::Value(PhaseGVN* phase) const {
2819 // Either input is TOP ==> the result is TOP
2820 const Type *t2 = phase->type(in(ValueIn));
2821 if( t2 == Type::TOP ) return Type::TOP;
2822
2823 if (t2 == TypePtr::NULL_PTR) {
2824 return t2;
2825 }
2826
2827 const Type* type = t2->is_oopptr();
2828 return type;
2829 }
2830
2831 Node* ShenandoahLoadReferenceBarrierNode::Identity(PhaseGVN* phase) {
2832 Node* value = in(ValueIn);
2833 if (!needs_barrier(phase, value)) {
2834 return value;
2835 }
2836 return this;
2837 }
2838
2839 bool ShenandoahLoadReferenceBarrierNode::needs_barrier(PhaseGVN* phase, Node* n) {
2840 Unique_Node_List visited;
2841 return needs_barrier_impl(phase, n, visited);
2842 }
2843
2844 bool ShenandoahLoadReferenceBarrierNode::needs_barrier_impl(PhaseGVN* phase, Node* n, Unique_Node_List &visited) {
2845 if (n == NULL) return false;
2846 if (visited.member(n)) {
2847 return false; // Been there.
2848 }
2849 visited.push(n);
2850
2851 if (n->is_Allocate()) {
2852 // tty->print_cr("optimize barrier on alloc");
2853 return false;
2854 }
2855 if (n->is_Call()) {
2856 // tty->print_cr("optimize barrier on call");
2857 return false;
2858 }
2859
2860 const Type* type = phase->type(n);
2861 if (type == Type::TOP) {
2862 return false;
2863 }
2864 if (type->make_ptr()->higher_equal(TypePtr::NULL_PTR)) {
2865 // tty->print_cr("optimize barrier on null");
2866 return false;
2867 }
2868 if (type->make_oopptr() && type->make_oopptr()->const_oop() != NULL) {
2869 // tty->print_cr("optimize barrier on constant");
2870 return false;
2871 }
2872
2873 switch (n->Opcode()) {
2874 case Op_AddP:
2875 return true; // TODO: Can refine?
2876 case Op_LoadP:
2877 case Op_ShenandoahCompareAndExchangeN:
2878 case Op_ShenandoahCompareAndExchangeP:
2879 case Op_CompareAndExchangeN:
2880 case Op_CompareAndExchangeP:
2881 case Op_GetAndSetN:
2882 case Op_GetAndSetP:
2883 return true;
2884 case Op_Phi: {
2885 for (uint i = 1; i < n->req(); i++) {
2886 if (needs_barrier_impl(phase, n->in(i), visited)) return true;
2887 }
2888 return false;
2889 }
2890 case Op_CheckCastPP:
2891 case Op_CastPP:
2892 return needs_barrier_impl(phase, n->in(1), visited);
2893 case Op_Proj:
2894 return needs_barrier_impl(phase, n->in(0), visited);
2895 case Op_ShenandoahLoadReferenceBarrier:
2896 // tty->print_cr("optimize barrier on barrier");
2897 return false;
2898 case Op_Parm:
2899 // tty->print_cr("optimize barrier on input arg");
2900 return false;
2901 case Op_DecodeN:
2902 case Op_EncodeP:
2903 return needs_barrier_impl(phase, n->in(1), visited);
2904 case Op_LoadN:
2905 return true;
2906 case Op_CMoveN:
2907 case Op_CMoveP:
2908 return needs_barrier_impl(phase, n->in(2), visited) ||
2909 needs_barrier_impl(phase, n->in(3), visited);
2910 case Op_ShenandoahEnqueueBarrier:
2911 return needs_barrier_impl(phase, n->in(1), visited);
2912 case Op_CreateEx:
2913 return false;
2914 default:
2915 break;
2916 }
2917 #ifdef ASSERT
2918 tty->print("need barrier on?: ");
2919 tty->print_cr("ins:");
2920 n->dump(2);
2921 tty->print_cr("outs:");
2922 n->dump(-2);
2923 ShouldNotReachHere();
2924 #endif
2925 return true;
2926 }
2927
2928 bool ShenandoahLoadReferenceBarrierNode::is_redundant() {
2929 Unique_Node_List visited;
2930 Node_Stack stack(0);
2931 stack.push(this, 0);
2932
2933 // Check if the barrier is actually useful: go over nodes looking for useful uses
2934 // (e.g. memory accesses). Stop once we detected a required use. Otherwise, walk
2935 // until we ran out of nodes, and then declare the barrier redundant.
2936 while (stack.size() > 0) {
2937 Node* n = stack.node();
2938 if (visited.member(n)) {
2939 stack.pop();
2940 continue;
2941 }
2942 visited.push(n);
2943 bool visit_users = false;
2944 switch (n->Opcode()) {
2945 case Op_CallStaticJava:
2946 // Uncommon traps don't need barriers, values are handled during deoptimization. It also affects
2947 // optimizing null-checks into implicit null-checks.
2948 if (n->as_CallStaticJava()->uncommon_trap_request() != 0) {
2949 break;
2950 }
2951 case Op_CallDynamicJava:
2952 case Op_CallLeaf:
2953 case Op_CallLeafNoFP:
2954 case Op_CompareAndSwapL:
2955 case Op_CompareAndSwapI:
2956 case Op_CompareAndSwapB:
2957 case Op_CompareAndSwapS:
2958 case Op_CompareAndSwapN:
2959 case Op_CompareAndSwapP:
2960 case Op_CompareAndExchangeL:
2961 case Op_CompareAndExchangeI:
2962 case Op_CompareAndExchangeB:
2963 case Op_CompareAndExchangeS:
2964 case Op_CompareAndExchangeN:
2965 case Op_CompareAndExchangeP:
2966 case Op_WeakCompareAndSwapL:
2967 case Op_WeakCompareAndSwapI:
2968 case Op_WeakCompareAndSwapB:
2969 case Op_WeakCompareAndSwapS:
2970 case Op_WeakCompareAndSwapN:
2971 case Op_WeakCompareAndSwapP:
2972 case Op_ShenandoahCompareAndSwapN:
2973 case Op_ShenandoahCompareAndSwapP:
2974 case Op_ShenandoahWeakCompareAndSwapN:
2975 case Op_ShenandoahWeakCompareAndSwapP:
2976 case Op_ShenandoahCompareAndExchangeN:
2977 case Op_ShenandoahCompareAndExchangeP:
2978 case Op_GetAndSetL:
2979 case Op_GetAndSetI:
2980 case Op_GetAndSetB:
2981 case Op_GetAndSetS:
2982 case Op_GetAndSetP:
2983 case Op_GetAndSetN:
2984 case Op_GetAndAddL:
2985 case Op_GetAndAddI:
2986 case Op_GetAndAddB:
2987 case Op_GetAndAddS:
2988 case Op_ShenandoahEnqueueBarrier:
2989 case Op_FastLock:
2990 case Op_FastUnlock:
2991 case Op_Rethrow:
2992 case Op_Return:
2993 case Op_StoreB:
2994 case Op_StoreC:
2995 case Op_StoreD:
2996 case Op_StoreF:
2997 case Op_StoreL:
2998 case Op_StoreLConditional:
2999 case Op_StoreI:
3000 case Op_StoreIConditional:
3001 case Op_StoreN:
3002 case Op_StoreP:
3003 case Op_StoreVector:
3004 case Op_StrInflatedCopy:
3005 case Op_StrCompressedCopy:
3006 case Op_EncodeP:
3007 case Op_CastP2X:
3008 case Op_SafePoint:
3009 case Op_EncodeISOArray:
3010 case Op_AryEq:
3011 case Op_StrEquals:
3012 case Op_StrComp:
3013 case Op_StrIndexOf:
3014 case Op_StrIndexOfChar:
3015 case Op_HasNegatives:
3016 // Known to require barriers
3017 return false;
3018 case Op_CmpP: {
3019 if (n->in(1)->bottom_type()->higher_equal(TypePtr::NULL_PTR) ||
3020 n->in(2)->bottom_type()->higher_equal(TypePtr::NULL_PTR)) {
3021 // One of the sides is known null, no need for barrier.
3022 } else {
3023 return false;
3024 }
3025 break;
3026 }
3027 case Op_LoadB:
3028 case Op_LoadUB:
3029 case Op_LoadUS:
3030 case Op_LoadD:
3031 case Op_LoadF:
3032 case Op_LoadL:
3033 case Op_LoadI:
3034 case Op_LoadS:
3035 case Op_LoadN:
3036 case Op_LoadP:
3037 case Op_LoadVector: {
3038 const TypePtr* adr_type = n->adr_type();
3039 int alias_idx = Compile::current()->get_alias_index(adr_type);
3040 Compile::AliasType* alias_type = Compile::current()->alias_type(alias_idx);
3041 ciField* field = alias_type->field();
3042 bool is_static = field != NULL && field->is_static();
3043 bool is_final = field != NULL && field->is_final();
3044
3045 if (ShenandoahOptimizeStaticFinals && is_static && is_final) {
3046 // Loading the constant does not require barriers: it should be handled
3047 // as part of GC roots already.
3048 } else {
3049 return false;
3050 }
3051 break;
3052 }
3053 case Op_Conv2B:
3054 case Op_LoadRange:
3055 case Op_LoadKlass:
3056 case Op_LoadNKlass:
3057 // Do not require barriers
3058 break;
3059 case Op_AddP:
3060 case Op_CheckCastPP:
3061 case Op_CastPP:
3062 case Op_CMoveP:
3063 case Op_Phi:
3064 case Op_ShenandoahLoadReferenceBarrier:
3065 // Whether or not these need the barriers depends on their users
3066 visit_users = true;
3067 break;
3068 default: {
3069 #ifdef ASSERT
3070 fatal("Unknown node in is_redundant: %s", NodeClassNames[n->Opcode()]);
3071 #else
3072 // Default to have excess barriers, rather than miss some.
3073 return false;
3074 #endif
3075 }
3076 }
3077
3078 stack.pop();
3079 if (visit_users) {
3080 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3081 Node* user = n->fast_out(i);
3082 if (user != NULL) {
3083 stack.push(user, 0);
3084 }
3085 }
3086 }
3087 }
3088
3089 // No need for barrier found.
3090 return true;
3091 }