1 /*
2 * Copyright (c) 2015, 2021, Red Hat, Inc. All rights reserved.
3 * Copyright (C) 2022 THL A29 Limited, a Tencent company. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.hpp"
27
28 #include "classfile/javaClasses.hpp"
29 #include "gc/shenandoah/c2/shenandoahSupport.hpp"
30 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
31 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp"
32 #include "gc/shenandoah/shenandoahForwarding.hpp"
33 #include "gc/shenandoah/shenandoahHeap.hpp"
34 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
35 #include "gc/shenandoah/shenandoahRuntime.hpp"
36 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
37 #include "opto/arraycopynode.hpp"
38 #include "opto/block.hpp"
39 #include "opto/callnode.hpp"
40 #include "opto/castnode.hpp"
41 #include "opto/movenode.hpp"
42 #include "opto/phaseX.hpp"
43 #include "opto/rootnode.hpp"
44 #include "opto/runtime.hpp"
45 #include "opto/subnode.hpp"
46
47 bool ShenandoahBarrierC2Support::expand(Compile* C, PhaseIterGVN& igvn) {
48 ShenandoahBarrierSetC2State* state = ShenandoahBarrierSetC2::bsc2()->state();
49 if ((state->iu_barriers_count() +
50 state->load_reference_barriers_count()) > 0) {
51 assert(C->post_loop_opts_phase(), "no loop opts allowed");
52 C->reset_post_loop_opts_phase(); // ... but we know what we are doing
53 bool attempt_more_loopopts = ShenandoahLoopOptsAfterExpansion;
54 C->clear_major_progress();
55 PhaseIdealLoop::optimize(igvn, LoopOptsShenandoahExpand);
56 if (C->failing()) return false;
57 PhaseIdealLoop::verify(igvn);
58 if (attempt_more_loopopts) {
59 C->set_major_progress();
60 if (!C->optimize_loops(igvn, LoopOptsShenandoahPostExpand)) {
61 return false;
62 }
63 C->clear_major_progress();
64
65 C->process_for_post_loop_opts_igvn(igvn);
66 if (C->failing()) return false;
67 }
68 C->set_post_loop_opts_phase(); // now for real!
69 }
70 return true;
71 }
72
73 bool ShenandoahBarrierC2Support::is_gc_state_test(Node* iff, int mask) {
74 if (!UseShenandoahGC) {
75 return false;
76 }
77 assert(iff->is_If(), "bad input");
78 if (iff->Opcode() != Op_If) {
79 return false;
80 }
81 Node* bol = iff->in(1);
82 if (!bol->is_Bool() || bol->as_Bool()->_test._test != BoolTest::ne) {
83 return false;
84 }
85 Node* cmp = bol->in(1);
86 if (cmp->Opcode() != Op_CmpI) {
87 return false;
88 }
89 Node* in1 = cmp->in(1);
90 Node* in2 = cmp->in(2);
91 if (in2->find_int_con(-1) != 0) {
92 return false;
93 }
94 if (in1->Opcode() != Op_AndI) {
95 return false;
96 }
97 in2 = in1->in(2);
98 if (in2->find_int_con(-1) != mask) {
99 return false;
100 }
101 in1 = in1->in(1);
102
103 return is_gc_state_load(in1);
104 }
105
106 bool ShenandoahBarrierC2Support::is_heap_stable_test(Node* iff) {
107 return is_gc_state_test(iff, ShenandoahHeap::HAS_FORWARDED);
108 }
109
110 bool ShenandoahBarrierC2Support::is_gc_state_load(Node *n) {
111 if (!UseShenandoahGC) {
112 return false;
113 }
114 if (n->Opcode() != Op_LoadB && n->Opcode() != Op_LoadUB) {
115 return false;
116 }
117 Node* addp = n->in(MemNode::Address);
118 if (!addp->is_AddP()) {
119 return false;
120 }
121 Node* base = addp->in(AddPNode::Address);
122 Node* off = addp->in(AddPNode::Offset);
123 if (base->Opcode() != Op_ThreadLocal) {
124 return false;
125 }
126 if (off->find_intptr_t_con(-1) != in_bytes(ShenandoahThreadLocalData::gc_state_offset())) {
127 return false;
128 }
129 return true;
130 }
131
132 bool ShenandoahBarrierC2Support::has_safepoint_between(Node* start, Node* stop, PhaseIdealLoop *phase) {
133 assert(phase->is_dominator(stop, start), "bad inputs");
134 ResourceMark rm;
135 Unique_Node_List wq;
136 wq.push(start);
137 for (uint next = 0; next < wq.size(); next++) {
138 Node *m = wq.at(next);
139 if (m == stop) {
140 continue;
141 }
142 if (m->is_SafePoint() && !m->is_CallLeaf()) {
143 return true;
144 }
145 if (m->is_Region()) {
146 for (uint i = 1; i < m->req(); i++) {
147 wq.push(m->in(i));
148 }
149 } else {
150 wq.push(m->in(0));
151 }
152 }
153 return false;
154 }
155
156 #ifdef ASSERT
157 bool ShenandoahBarrierC2Support::verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used) {
158 assert(phis.size() == 0, "");
159
160 while (true) {
161 if (in->bottom_type() == TypePtr::NULL_PTR) {
162 if (trace) {tty->print_cr("null");}
163 } else if (!in->bottom_type()->make_ptr()->make_oopptr()) {
164 if (trace) {tty->print_cr("Non oop");}
165 } else {
166 if (in->is_ConstraintCast()) {
167 in = in->in(1);
168 continue;
169 } else if (in->is_AddP()) {
170 assert(!in->in(AddPNode::Address)->is_top(), "no raw memory access");
171 in = in->in(AddPNode::Address);
172 continue;
173 } else if (in->is_Con()) {
174 if (trace) {
175 tty->print("Found constant");
176 in->dump();
177 }
178 } else if (in->Opcode() == Op_Parm) {
179 if (trace) {
180 tty->print("Found argument");
181 }
182 } else if (in->Opcode() == Op_CreateEx) {
183 if (trace) {
184 tty->print("Found create-exception");
185 }
186 } else if (in->Opcode() == Op_LoadP && in->adr_type() == TypeRawPtr::BOTTOM) {
187 if (trace) {
188 tty->print("Found raw LoadP (OSR argument?)");
189 }
190 } else if (in->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
191 if (t == ShenandoahOopStore) {
192 uint i = 0;
193 for (; i < phis.size(); i++) {
194 Node* n = phis.node_at(i);
195 if (n->Opcode() == Op_ShenandoahIUBarrier) {
196 break;
197 }
198 }
199 if (i == phis.size()) {
200 return false;
201 }
202 }
203 barriers_used.push(in);
204 if (trace) {tty->print("Found barrier"); in->dump();}
205 } else if (in->Opcode() == Op_ShenandoahIUBarrier) {
206 if (t != ShenandoahOopStore) {
207 in = in->in(1);
208 continue;
209 }
210 if (trace) {tty->print("Found enqueue barrier"); in->dump();}
211 phis.push(in, in->req());
212 in = in->in(1);
213 continue;
214 } else if (in->is_Proj() && in->in(0)->is_Allocate()) {
215 if (trace) {
216 tty->print("Found alloc");
217 in->in(0)->dump();
218 }
219 } else if (in->is_Proj() && (in->in(0)->Opcode() == Op_CallStaticJava || in->in(0)->Opcode() == Op_CallDynamicJava)) {
220 if (trace) {
221 tty->print("Found Java call");
222 }
223 } else if (in->is_Phi()) {
224 if (!visited.test_set(in->_idx)) {
225 if (trace) {tty->print("Pushed phi:"); in->dump();}
226 phis.push(in, 2);
227 in = in->in(1);
228 continue;
229 }
230 if (trace) {tty->print("Already seen phi:"); in->dump();}
231 } else if (in->Opcode() == Op_CMoveP || in->Opcode() == Op_CMoveN) {
232 if (!visited.test_set(in->_idx)) {
233 if (trace) {tty->print("Pushed cmovep:"); in->dump();}
234 phis.push(in, CMoveNode::IfTrue);
235 in = in->in(CMoveNode::IfFalse);
236 continue;
237 }
238 if (trace) {tty->print("Already seen cmovep:"); in->dump();}
239 } else if (in->Opcode() == Op_EncodeP || in->Opcode() == Op_DecodeN) {
240 in = in->in(1);
241 continue;
242 } else {
243 return false;
244 }
245 }
246 bool cont = false;
247 while (phis.is_nonempty()) {
248 uint idx = phis.index();
249 Node* phi = phis.node();
250 if (idx >= phi->req()) {
251 if (trace) {tty->print("Popped phi:"); phi->dump();}
252 phis.pop();
253 continue;
254 }
255 if (trace) {tty->print("Next entry(%d) for phi:", idx); phi->dump();}
256 in = phi->in(idx);
257 phis.set_index(idx+1);
258 cont = true;
259 break;
260 }
261 if (!cont) {
262 break;
263 }
264 }
265 return true;
266 }
267
268 void ShenandoahBarrierC2Support::report_verify_failure(const char* msg, Node* n1, Node* n2) {
269 if (n1 != nullptr) {
270 n1->dump(+10);
271 }
272 if (n2 != nullptr) {
273 n2->dump(+10);
274 }
275 fatal("%s", msg);
276 }
277
278 void ShenandoahBarrierC2Support::verify(RootNode* root) {
279 ResourceMark rm;
280 Unique_Node_List wq;
281 GrowableArray<Node*> barriers;
282 Unique_Node_List barriers_used;
283 Node_Stack phis(0);
284 VectorSet visited;
285 const bool trace = false;
286 const bool verify_no_useless_barrier = false;
287
288 wq.push(root);
289 for (uint next = 0; next < wq.size(); next++) {
290 Node *n = wq.at(next);
291 if (n->is_Load()) {
292 const bool trace = false;
293 if (trace) {tty->print("Verifying"); n->dump();}
294 if (n->Opcode() == Op_LoadRange || n->Opcode() == Op_LoadKlass || n->Opcode() == Op_LoadNKlass) {
295 if (trace) {tty->print_cr("Load range/klass");}
296 } else {
297 const TypePtr* adr_type = n->as_Load()->adr_type();
298
299 if (adr_type->isa_oopptr() && adr_type->is_oopptr()->offset() == oopDesc::mark_offset_in_bytes()) {
300 if (trace) {tty->print_cr("Mark load");}
301 } else if (adr_type->isa_instptr() &&
302 adr_type->is_instptr()->instance_klass()->is_subtype_of(Compile::current()->env()->Reference_klass()) &&
303 adr_type->is_instptr()->offset() == java_lang_ref_Reference::referent_offset()) {
304 if (trace) {tty->print_cr("Reference.get()");}
305 } else if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahLoad, trace, barriers_used)) {
306 report_verify_failure("Shenandoah verification: Load should have barriers", n);
307 }
308 }
309 } else if (n->is_Store()) {
310 const bool trace = false;
311
312 if (trace) {tty->print("Verifying"); n->dump();}
313 if (n->in(MemNode::ValueIn)->bottom_type()->make_oopptr()) {
314 Node* adr = n->in(MemNode::Address);
315 bool verify = true;
316
317 if (adr->is_AddP() && adr->in(AddPNode::Base)->is_top()) {
318 adr = adr->in(AddPNode::Address);
319 if (adr->is_AddP()) {
320 assert(adr->in(AddPNode::Base)->is_top(), "");
321 adr = adr->in(AddPNode::Address);
322 if (adr->Opcode() == Op_LoadP &&
323 adr->in(MemNode::Address)->in(AddPNode::Base)->is_top() &&
324 adr->in(MemNode::Address)->in(AddPNode::Address)->Opcode() == Op_ThreadLocal &&
325 adr->in(MemNode::Address)->in(AddPNode::Offset)->find_intptr_t_con(-1) == in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset())) {
326 if (trace) {tty->print_cr("SATB prebarrier");}
327 verify = false;
328 }
329 }
330 }
331
332 if (verify && !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahIUBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
333 report_verify_failure("Shenandoah verification: Store should have barriers", n);
334 }
335 }
336 if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
337 report_verify_failure("Shenandoah verification: Store (address) should have barriers", n);
338 }
339 } else if (n->Opcode() == Op_CmpP) {
340 const bool trace = false;
341
342 Node* in1 = n->in(1);
343 Node* in2 = n->in(2);
344 if (in1->bottom_type()->isa_oopptr()) {
345 if (trace) {tty->print("Verifying"); n->dump();}
346
347 bool mark_inputs = false;
348 if (in1->bottom_type() == TypePtr::NULL_PTR || in2->bottom_type() == TypePtr::NULL_PTR ||
349 (in1->is_Con() || in2->is_Con())) {
350 if (trace) {tty->print_cr("Comparison against a constant");}
351 mark_inputs = true;
352 } else if ((in1->is_CheckCastPP() && in1->in(1)->is_Proj() && in1->in(1)->in(0)->is_Allocate()) ||
353 (in2->is_CheckCastPP() && in2->in(1)->is_Proj() && in2->in(1)->in(0)->is_Allocate())) {
354 if (trace) {tty->print_cr("Comparison with newly alloc'ed object");}
355 mark_inputs = true;
356 } else {
357 assert(in2->bottom_type()->isa_oopptr(), "");
358
359 if (!verify_helper(in1, phis, visited, ShenandoahStore, trace, barriers_used) ||
360 !verify_helper(in2, phis, visited, ShenandoahStore, trace, barriers_used)) {
361 report_verify_failure("Shenandoah verification: Cmp should have barriers", n);
362 }
363 }
364 if (verify_no_useless_barrier &&
365 mark_inputs &&
366 (!verify_helper(in1, phis, visited, ShenandoahValue, trace, barriers_used) ||
367 !verify_helper(in2, phis, visited, ShenandoahValue, trace, barriers_used))) {
368 phis.clear();
369 visited.reset();
370 }
371 }
372 } else if (n->is_LoadStore()) {
373 if (n->in(MemNode::ValueIn)->bottom_type()->make_ptr() &&
374 !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahIUBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
375 report_verify_failure("Shenandoah verification: LoadStore (value) should have barriers", n);
376 }
377
378 if (n->in(MemNode::Address)->bottom_type()->make_oopptr() && !verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
379 report_verify_failure("Shenandoah verification: LoadStore (address) should have barriers", n);
380 }
381 } else if (n->Opcode() == Op_CallLeafNoFP || n->Opcode() == Op_CallLeaf) {
382 CallNode* call = n->as_Call();
383
384 static struct {
385 const char* name;
386 struct {
387 int pos;
388 verify_type t;
389 } args[6];
390 } calls[] = {
391 "array_partition_stub",
392 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+4, ShenandoahStore }, { -1, ShenandoahNone },
393 { -1, ShenandoahNone }, { -1, ShenandoahNone }, { -1, ShenandoahNone } },
394 "arraysort_stub",
395 { { TypeFunc::Parms, ShenandoahStore }, { -1, ShenandoahNone }, { -1, ShenandoahNone },
396 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
397 "aescrypt_encryptBlock",
398 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
399 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
400 "aescrypt_decryptBlock",
401 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
402 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
403 "multiplyToLen",
404 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { TypeFunc::Parms+4, ShenandoahStore },
405 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
406 "squareToLen",
407 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { -1, ShenandoahNone},
408 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
409 "montgomery_multiply",
410 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
411 { TypeFunc::Parms+6, ShenandoahStore }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
412 "montgomery_square",
413 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+5, ShenandoahStore },
414 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
415 "mulAdd",
416 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
417 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
418 "vectorizedMismatch",
419 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
420 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
421 "updateBytesCRC32",
422 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
423 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
424 "updateBytesAdler32",
425 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
426 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
427 "updateBytesCRC32C",
428 { { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahLoad}, { -1, ShenandoahNone},
429 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
430 "counterMode_AESCrypt",
431 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
432 { TypeFunc::Parms+3, ShenandoahStore }, { TypeFunc::Parms+5, ShenandoahStore }, { TypeFunc::Parms+6, ShenandoahStore } },
433 "cipherBlockChaining_encryptAESCrypt",
434 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
435 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
436 "cipherBlockChaining_decryptAESCrypt",
437 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
438 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
439 "shenandoah_clone_barrier",
440 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
441 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
442 "ghash_processBlocks",
443 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
444 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
445 "sha1_implCompress",
446 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
447 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
448 "sha256_implCompress",
449 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
450 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
451 "sha512_implCompress",
452 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
453 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
454 "sha1_implCompressMB",
455 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
456 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
457 "sha256_implCompressMB",
458 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
459 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
460 "sha512_implCompressMB",
461 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
462 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
463 "encodeBlock",
464 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
465 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
466 "decodeBlock",
467 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
468 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
469 };
470
471 if (call->is_call_to_arraycopystub()) {
472 Node* dest = nullptr;
473 const TypeTuple* args = n->as_Call()->_tf->domain();
474 for (uint i = TypeFunc::Parms, j = 0; i < args->cnt(); i++) {
475 if (args->field_at(i)->isa_ptr()) {
476 j++;
477 if (j == 2) {
478 dest = n->in(i);
479 break;
480 }
481 }
482 }
483 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahLoad, trace, barriers_used) ||
484 !verify_helper(dest, phis, visited, ShenandoahStore, trace, barriers_used)) {
485 report_verify_failure("Shenandoah verification: ArrayCopy should have barriers", n);
486 }
487 } else if (strlen(call->_name) > 5 &&
488 !strcmp(call->_name + strlen(call->_name) - 5, "_fill")) {
489 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahStore, trace, barriers_used)) {
490 report_verify_failure("Shenandoah verification: _fill should have barriers", n);
491 }
492 } else if (!strcmp(call->_name, "shenandoah_wb_pre")) {
493 // skip
494 } else {
495 const int calls_len = sizeof(calls) / sizeof(calls[0]);
496 int i = 0;
497 for (; i < calls_len; i++) {
498 if (!strcmp(calls[i].name, call->_name)) {
499 break;
500 }
501 }
502 if (i != calls_len) {
503 const uint args_len = sizeof(calls[0].args) / sizeof(calls[0].args[0]);
504 for (uint j = 0; j < args_len; j++) {
505 int pos = calls[i].args[j].pos;
506 if (pos == -1) {
507 break;
508 }
509 if (!verify_helper(call->in(pos), phis, visited, calls[i].args[j].t, trace, barriers_used)) {
510 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
511 }
512 }
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 uint k = 0;
517 for (; k < args_len && calls[i].args[k].pos != (int)j; k++);
518 if (k == args_len) {
519 fatal("arg %d for call %s not covered", j, call->_name);
520 }
521 }
522 }
523 } else {
524 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
525 if (call->in(j)->bottom_type()->make_ptr() &&
526 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
527 fatal("%s not covered", call->_name);
528 }
529 }
530 }
531 }
532 } else if (n->Opcode() == Op_ShenandoahIUBarrier || n->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
533 // skip
534 } else if (n->is_AddP()
535 || n->is_Phi()
536 || n->is_ConstraintCast()
537 || n->Opcode() == Op_Return
538 || n->Opcode() == Op_CMoveP
539 || n->Opcode() == Op_CMoveN
540 || n->Opcode() == Op_Rethrow
541 || n->is_MemBar()
542 || n->Opcode() == Op_Conv2B
543 || n->Opcode() == Op_SafePoint
544 || n->is_CallJava()
545 || n->Opcode() == Op_Unlock
546 || n->Opcode() == Op_EncodeP
547 || n->Opcode() == Op_DecodeN) {
548 // nothing to do
549 } else {
550 static struct {
551 int opcode;
552 struct {
553 int pos;
554 verify_type t;
555 } inputs[2];
556 } others[] = {
557 Op_FastLock,
558 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
559 Op_Lock,
560 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone} },
561 Op_ArrayCopy,
562 { { ArrayCopyNode::Src, ShenandoahLoad }, { ArrayCopyNode::Dest, ShenandoahStore } },
563 Op_StrCompressedCopy,
564 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
565 Op_StrInflatedCopy,
566 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
567 Op_AryEq,
568 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
569 Op_StrIndexOf,
570 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
571 Op_StrComp,
572 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
573 Op_StrEquals,
574 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
575 Op_VectorizedHashCode,
576 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
577 Op_EncodeISOArray,
578 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
579 Op_CountPositives,
580 { { 2, ShenandoahLoad }, { -1, ShenandoahNone} },
581 Op_CastP2X,
582 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
583 Op_StrIndexOfChar,
584 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
585 };
586
587 const int others_len = sizeof(others) / sizeof(others[0]);
588 int i = 0;
589 for (; i < others_len; i++) {
590 if (others[i].opcode == n->Opcode()) {
591 break;
592 }
593 }
594 uint stop = n->is_Call() ? n->as_Call()->tf()->domain()->cnt() : n->req();
595 if (i != others_len) {
596 const uint inputs_len = sizeof(others[0].inputs) / sizeof(others[0].inputs[0]);
597 for (uint j = 0; j < inputs_len; j++) {
598 int pos = others[i].inputs[j].pos;
599 if (pos == -1) {
600 break;
601 }
602 if (!verify_helper(n->in(pos), phis, visited, others[i].inputs[j].t, trace, barriers_used)) {
603 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
604 }
605 }
606 for (uint j = 1; j < stop; j++) {
607 if (n->in(j) != nullptr && n->in(j)->bottom_type()->make_ptr() &&
608 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
609 uint k = 0;
610 for (; k < inputs_len && others[i].inputs[k].pos != (int)j; k++);
611 if (k == inputs_len) {
612 fatal("arg %d for node %s not covered", j, n->Name());
613 }
614 }
615 }
616 } else {
617 for (uint j = 1; j < stop; j++) {
618 if (n->in(j) != nullptr && n->in(j)->bottom_type()->make_ptr() &&
619 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
620 fatal("%s not covered", n->Name());
621 }
622 }
623 }
624 }
625
626 if (n->is_SafePoint()) {
627 SafePointNode* sfpt = n->as_SafePoint();
628 if (verify_no_useless_barrier && sfpt->jvms() != nullptr) {
629 for (uint i = sfpt->jvms()->scloff(); i < sfpt->jvms()->endoff(); i++) {
630 if (!verify_helper(sfpt->in(i), phis, visited, ShenandoahLoad, trace, barriers_used)) {
631 phis.clear();
632 visited.reset();
633 }
634 }
635 }
636 }
637 }
638
639 if (verify_no_useless_barrier) {
640 for (int i = 0; i < barriers.length(); i++) {
641 Node* n = barriers.at(i);
642 if (!barriers_used.member(n)) {
643 tty->print("XXX useless barrier"); n->dump(-2);
644 ShouldNotReachHere();
645 }
646 }
647 }
648 }
649 #endif
650
651 bool ShenandoahBarrierC2Support::is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase) {
652 // That both nodes have the same control is not sufficient to prove
653 // domination, verify that there's no path from d to n
654 ResourceMark rm;
655 Unique_Node_List wq;
656 wq.push(d);
657 for (uint next = 0; next < wq.size(); next++) {
658 Node *m = wq.at(next);
659 if (m == n) {
660 return false;
661 }
662 if (m->is_Phi() && m->in(0)->is_Loop()) {
663 assert(phase->ctrl_or_self(m->in(LoopNode::EntryControl)) != c, "following loop entry should lead to new control");
664 } else {
665 if (m->is_Store() || m->is_LoadStore()) {
666 // Take anti-dependencies into account
667 Node* mem = m->in(MemNode::Memory);
668 for (DUIterator_Fast imax, i = mem->fast_outs(imax); i < imax; i++) {
669 Node* u = mem->fast_out(i);
670 if (u->is_Load() && phase->C->can_alias(m->adr_type(), phase->C->get_alias_index(u->adr_type())) &&
671 phase->ctrl_or_self(u) == c) {
672 wq.push(u);
673 }
674 }
675 }
676 for (uint i = 0; i < m->req(); i++) {
677 if (m->in(i) != nullptr && phase->ctrl_or_self(m->in(i)) == c) {
678 wq.push(m->in(i));
679 }
680 }
681 }
682 }
683 return true;
684 }
685
686 bool ShenandoahBarrierC2Support::is_dominator(Node* d_c, Node* n_c, Node* d, Node* n, PhaseIdealLoop* phase) {
687 if (d_c != n_c) {
688 return phase->is_dominator(d_c, n_c);
689 }
690 return is_dominator_same_ctrl(d_c, d, n, phase);
691 }
692
693 Node* next_mem(Node* mem, int alias) {
694 Node* res = nullptr;
695 if (mem->is_Proj()) {
696 res = mem->in(0);
697 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
698 res = mem->in(TypeFunc::Memory);
699 } else if (mem->is_Phi()) {
700 res = mem->in(1);
701 } else if (mem->is_MergeMem()) {
702 res = mem->as_MergeMem()->memory_at(alias);
703 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
704 assert(alias == Compile::AliasIdxRaw, "following raw memory can't lead to a barrier");
705 res = mem->in(MemNode::Memory);
706 } else {
707 #ifdef ASSERT
708 mem->dump();
709 #endif
710 ShouldNotReachHere();
711 }
712 return res;
713 }
714
715 Node* ShenandoahBarrierC2Support::no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase) {
716 Node* iffproj = nullptr;
717 while (c != dom) {
718 Node* next = phase->idom(c);
719 assert(next->unique_ctrl_out_or_null() == c || c->is_Proj() || c->is_Region(), "multiple control flow out but no proj or region?");
720 if (c->is_Region()) {
721 ResourceMark rm;
722 Unique_Node_List wq;
723 wq.push(c);
724 for (uint i = 0; i < wq.size(); i++) {
725 Node *n = wq.at(i);
726 if (n == next) {
727 continue;
728 }
729 if (n->is_Region()) {
730 for (uint j = 1; j < n->req(); j++) {
731 wq.push(n->in(j));
732 }
733 } else {
734 wq.push(n->in(0));
735 }
736 }
737 for (uint i = 0; i < wq.size(); i++) {
738 Node *n = wq.at(i);
739 assert(n->is_CFG(), "");
740 if (n->is_Multi()) {
741 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
742 Node* u = n->fast_out(j);
743 if (u->is_CFG()) {
744 if (!wq.member(u) && !u->as_Proj()->is_uncommon_trap_proj()) {
745 return NodeSentinel;
746 }
747 }
748 }
749 }
750 }
751 } else if (c->is_Proj()) {
752 if (c->is_IfProj()) {
753 if (c->as_Proj()->is_uncommon_trap_if_pattern() != nullptr) {
754 // continue;
755 } else {
756 if (!allow_one_proj) {
757 return NodeSentinel;
758 }
759 if (iffproj == nullptr) {
760 iffproj = c;
761 } else {
762 return NodeSentinel;
763 }
764 }
765 } else if (c->Opcode() == Op_JumpProj) {
766 return NodeSentinel; // unsupported
767 } else if (c->Opcode() == Op_CatchProj) {
768 return NodeSentinel; // unsupported
769 } else if (c->Opcode() == Op_CProj && next->is_NeverBranch()) {
770 return NodeSentinel; // unsupported
771 } else {
772 assert(next->unique_ctrl_out() == c, "unsupported branch pattern");
773 }
774 }
775 c = next;
776 }
777 return iffproj;
778 }
779
780 Node* ShenandoahBarrierC2Support::dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase) {
781 ResourceMark rm;
782 VectorSet wq;
783 wq.set(mem->_idx);
784 mem_ctrl = phase->ctrl_or_self(mem);
785 while (!phase->is_dominator(mem_ctrl, ctrl) || mem_ctrl == ctrl) {
786 mem = next_mem(mem, alias);
787 if (wq.test_set(mem->_idx)) {
788 return nullptr;
789 }
790 mem_ctrl = phase->ctrl_or_self(mem);
791 }
792 if (mem->is_MergeMem()) {
793 mem = mem->as_MergeMem()->memory_at(alias);
794 mem_ctrl = phase->ctrl_or_self(mem);
795 }
796 return mem;
797 }
798
799 Node* ShenandoahBarrierC2Support::find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase) {
800 Node* mem = nullptr;
801 Node* c = ctrl;
802 do {
803 if (c->is_Region()) {
804 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax && mem == nullptr; i++) {
805 Node* u = c->fast_out(i);
806 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
807 if (u->adr_type() == TypePtr::BOTTOM) {
808 mem = u;
809 }
810 }
811 }
812 } else {
813 if (c->is_Call() && c->as_Call()->adr_type() != nullptr) {
814 CallProjections projs;
815 c->as_Call()->extract_projections(&projs, true, false);
816 if (projs.fallthrough_memproj != nullptr) {
817 if (projs.fallthrough_memproj->adr_type() == TypePtr::BOTTOM) {
818 if (projs.catchall_memproj == nullptr) {
819 mem = projs.fallthrough_memproj;
820 } else {
821 if (phase->is_dominator(projs.fallthrough_catchproj, ctrl)) {
822 mem = projs.fallthrough_memproj;
823 } else {
824 assert(phase->is_dominator(projs.catchall_catchproj, ctrl), "one proj must dominate barrier");
825 mem = projs.catchall_memproj;
826 }
827 }
828 }
829 } else {
830 Node* proj = c->as_Call()->proj_out(TypeFunc::Memory);
831 if (proj != nullptr &&
832 proj->adr_type() == TypePtr::BOTTOM) {
833 mem = proj;
834 }
835 }
836 } else {
837 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
838 Node* u = c->fast_out(i);
839 if (u->is_Proj() &&
840 u->bottom_type() == Type::MEMORY &&
841 u->adr_type() == TypePtr::BOTTOM) {
842 assert(c->is_SafePoint() || c->is_MemBar() || c->is_Start(), "");
843 assert(mem == nullptr, "only one proj");
844 mem = u;
845 }
846 }
847 assert(!c->is_Call() || c->as_Call()->adr_type() != nullptr || mem == nullptr, "no mem projection expected");
848 }
849 }
850 c = phase->idom(c);
851 } while (mem == nullptr);
852 return mem;
853 }
854
855 void ShenandoahBarrierC2Support::follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase) {
856 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
857 Node* u = n->fast_out(i);
858 if (!u->is_CFG() && phase->get_ctrl(u) == ctrl && (!u->is_Phi() || !u->in(0)->is_Loop() || u->in(LoopNode::LoopBackControl) != n)) {
859 uses.push(u);
860 }
861 }
862 }
863
864 static void hide_strip_mined_loop(OuterStripMinedLoopNode* outer, CountedLoopNode* inner, PhaseIdealLoop* phase) {
865 OuterStripMinedLoopEndNode* le = inner->outer_loop_end();
866 Node* new_outer = new LoopNode(outer->in(LoopNode::EntryControl), outer->in(LoopNode::LoopBackControl));
867 phase->register_control(new_outer, phase->get_loop(outer), outer->in(LoopNode::EntryControl));
868 Node* new_le = new IfNode(le->in(0), le->in(1), le->_prob, le->_fcnt);
869 phase->register_control(new_le, phase->get_loop(le), le->in(0));
870 phase->lazy_replace(outer, new_outer);
871 phase->lazy_replace(le, new_le);
872 inner->clear_strip_mined();
873 }
874
875 void ShenandoahBarrierC2Support::test_gc_state(Node*& ctrl, Node* raw_mem, Node*& test_fail_ctrl,
876 PhaseIdealLoop* phase, int flags) {
877 PhaseIterGVN& igvn = phase->igvn();
878 Node* old_ctrl = ctrl;
879
880 Node* thread = new ThreadLocalNode();
881 Node* gc_state_offset = igvn.MakeConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
882 Node* gc_state_addr = new AddPNode(phase->C->top(), thread, gc_state_offset);
883 Node* gc_state = new LoadBNode(old_ctrl, raw_mem, gc_state_addr,
884 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(nullptr),
885 TypeInt::BYTE, MemNode::unordered);
886 Node* gc_state_and = new AndINode(gc_state, igvn.intcon(flags));
887 Node* gc_state_cmp = new CmpINode(gc_state_and, igvn.zerocon(T_INT));
888 Node* gc_state_bool = new BoolNode(gc_state_cmp, BoolTest::ne);
889
890 IfNode* gc_state_iff = new IfNode(old_ctrl, gc_state_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
891 ctrl = new IfTrueNode(gc_state_iff);
892 test_fail_ctrl = new IfFalseNode(gc_state_iff);
893
894 IdealLoopTree* loop = phase->get_loop(old_ctrl);
895 phase->register_control(gc_state_iff, loop, old_ctrl);
896 phase->register_control(ctrl, loop, gc_state_iff);
897 phase->register_control(test_fail_ctrl, loop, gc_state_iff);
898
899 phase->register_new_node(thread, old_ctrl);
900 phase->register_new_node(gc_state_addr, old_ctrl);
901 phase->register_new_node(gc_state, old_ctrl);
902 phase->register_new_node(gc_state_and, old_ctrl);
903 phase->register_new_node(gc_state_cmp, old_ctrl);
904 phase->register_new_node(gc_state_bool, old_ctrl);
905
906 phase->set_ctrl(gc_state_offset, phase->C->root());
907
908 assert(is_gc_state_test(gc_state_iff, flags), "Should match the shape");
909 }
910
911 void ShenandoahBarrierC2Support::test_null(Node*& ctrl, Node* val, Node*& null_ctrl, PhaseIdealLoop* phase) {
912 Node* old_ctrl = ctrl;
913 PhaseIterGVN& igvn = phase->igvn();
914
915 const Type* val_t = igvn.type(val);
916 if (val_t->meet(TypePtr::NULL_PTR) == val_t) {
917 Node* null_cmp = new CmpPNode(val, igvn.zerocon(T_OBJECT));
918 Node* null_test = new BoolNode(null_cmp, BoolTest::ne);
919
920 IfNode* null_iff = new IfNode(old_ctrl, null_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
921 ctrl = new IfTrueNode(null_iff);
922 null_ctrl = new IfFalseNode(null_iff);
923
924 IdealLoopTree* loop = phase->get_loop(old_ctrl);
925 phase->register_control(null_iff, loop, old_ctrl);
926 phase->register_control(ctrl, loop, null_iff);
927 phase->register_control(null_ctrl, loop, null_iff);
928
929 phase->register_new_node(null_cmp, old_ctrl);
930 phase->register_new_node(null_test, old_ctrl);
931 }
932 }
933
934 void ShenandoahBarrierC2Support::test_in_cset(Node*& ctrl, Node*& not_cset_ctrl, Node* val, Node* raw_mem, PhaseIdealLoop* phase) {
935 Node* old_ctrl = ctrl;
936 PhaseIterGVN& igvn = phase->igvn();
937
938 Node* raw_val = new CastP2XNode(old_ctrl, val);
939 Node* cset_idx = new URShiftXNode(raw_val, igvn.intcon(ShenandoahHeapRegion::region_size_bytes_shift_jint()));
940
941 // Figure out the target cset address with raw pointer math.
942 // This avoids matching AddP+LoadB that would emit inefficient code.
943 // See JDK-8245465.
944 Node* cset_addr_ptr = igvn.makecon(TypeRawPtr::make(ShenandoahHeap::in_cset_fast_test_addr()));
945 Node* cset_addr = new CastP2XNode(old_ctrl, cset_addr_ptr);
946 Node* cset_load_addr = new AddXNode(cset_addr, cset_idx);
947 Node* cset_load_ptr = new CastX2PNode(cset_load_addr);
948
949 Node* cset_load = new LoadBNode(old_ctrl, raw_mem, cset_load_ptr,
950 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(nullptr),
951 TypeInt::BYTE, MemNode::unordered);
952 Node* cset_cmp = new CmpINode(cset_load, igvn.zerocon(T_INT));
953 Node* cset_bool = new BoolNode(cset_cmp, BoolTest::ne);
954
955 IfNode* cset_iff = new IfNode(old_ctrl, cset_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
956 ctrl = new IfTrueNode(cset_iff);
957 not_cset_ctrl = new IfFalseNode(cset_iff);
958
959 IdealLoopTree *loop = phase->get_loop(old_ctrl);
960 phase->register_control(cset_iff, loop, old_ctrl);
961 phase->register_control(ctrl, loop, cset_iff);
962 phase->register_control(not_cset_ctrl, loop, cset_iff);
963
964 phase->set_ctrl(cset_addr_ptr, phase->C->root());
965
966 phase->register_new_node(raw_val, old_ctrl);
967 phase->register_new_node(cset_idx, old_ctrl);
968 phase->register_new_node(cset_addr, old_ctrl);
969 phase->register_new_node(cset_load_addr, old_ctrl);
970 phase->register_new_node(cset_load_ptr, old_ctrl);
971 phase->register_new_node(cset_load, old_ctrl);
972 phase->register_new_node(cset_cmp, old_ctrl);
973 phase->register_new_node(cset_bool, old_ctrl);
974 }
975
976 void ShenandoahBarrierC2Support::call_lrb_stub(Node*& ctrl, Node*& val, Node* load_addr,
977 DecoratorSet decorators, PhaseIdealLoop* phase) {
978 IdealLoopTree*loop = phase->get_loop(ctrl);
979 const TypePtr* obj_type = phase->igvn().type(val)->is_oopptr();
980
981 address calladdr = nullptr;
982 const char* name = nullptr;
983 bool is_strong = ShenandoahBarrierSet::is_strong_access(decorators);
984 bool is_weak = ShenandoahBarrierSet::is_weak_access(decorators);
985 bool is_phantom = ShenandoahBarrierSet::is_phantom_access(decorators);
986 bool is_native = ShenandoahBarrierSet::is_native_access(decorators);
987 bool is_narrow = UseCompressedOops && !is_native;
988 if (is_strong) {
989 if (is_narrow) {
990 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong_narrow);
991 name = "load_reference_barrier_strong_narrow";
992 } else {
993 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong);
994 name = "load_reference_barrier_strong";
995 }
996 } else if (is_weak) {
997 if (is_narrow) {
998 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak_narrow);
999 name = "load_reference_barrier_weak_narrow";
1000 } else {
1001 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak);
1002 name = "load_reference_barrier_weak";
1003 }
1004 } else {
1005 assert(is_phantom, "only remaining strength");
1006 if (is_narrow) {
1007 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom_narrow);
1008 name = "load_reference_barrier_phantom_narrow";
1009 } else {
1010 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom);
1011 name = "load_reference_barrier_phantom";
1012 }
1013 }
1014 Node* call = new CallLeafNode(ShenandoahBarrierSetC2::shenandoah_load_reference_barrier_Type(), calladdr, name, TypeRawPtr::BOTTOM);
1015
1016 call->init_req(TypeFunc::Control, ctrl);
1017 call->init_req(TypeFunc::I_O, phase->C->top());
1018 call->init_req(TypeFunc::Memory, phase->C->top());
1019 call->init_req(TypeFunc::FramePtr, phase->C->top());
1020 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
1021 call->init_req(TypeFunc::Parms, val);
1022 call->init_req(TypeFunc::Parms+1, load_addr);
1023 phase->register_control(call, loop, ctrl);
1024 ctrl = new ProjNode(call, TypeFunc::Control);
1025 phase->register_control(ctrl, loop, call);
1026 val = new ProjNode(call, TypeFunc::Parms);
1027 phase->register_new_node(val, call);
1028 val = new CheckCastPPNode(ctrl, val, obj_type);
1029 phase->register_new_node(val, ctrl);
1030 }
1031
1032 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) {
1033 Node* ctrl = phase->get_ctrl(barrier);
1034 Node* init_raw_mem = fixer.find_mem(ctrl, barrier);
1035
1036 // Update the control of all nodes that should be after the
1037 // barrier control flow
1038 uses.clear();
1039 // Every node that is control dependent on the barrier's input
1040 // control will be after the expanded barrier. The raw memory (if
1041 // its memory is control dependent on the barrier's input control)
1042 // must stay above the barrier.
1043 uses_to_ignore.clear();
1044 if (phase->has_ctrl(init_raw_mem) && phase->get_ctrl(init_raw_mem) == ctrl && !init_raw_mem->is_Phi()) {
1045 uses_to_ignore.push(init_raw_mem);
1046 }
1047 for (uint next = 0; next < uses_to_ignore.size(); next++) {
1048 Node *n = uses_to_ignore.at(next);
1049 for (uint i = 0; i < n->req(); i++) {
1050 Node* in = n->in(i);
1051 if (in != nullptr && phase->has_ctrl(in) && phase->get_ctrl(in) == ctrl) {
1052 uses_to_ignore.push(in);
1053 }
1054 }
1055 }
1056 for (DUIterator_Fast imax, i = ctrl->fast_outs(imax); i < imax; i++) {
1057 Node* u = ctrl->fast_out(i);
1058 if (u->_idx < last &&
1059 u != barrier &&
1060 !uses_to_ignore.member(u) &&
1061 (u->in(0) != ctrl || (!u->is_Region() && !u->is_Phi())) &&
1062 (ctrl->Opcode() != Op_CatchProj || u->Opcode() != Op_CreateEx)) {
1063 Node* old_c = phase->ctrl_or_self(u);
1064 Node* c = old_c;
1065 if (c != ctrl ||
1066 is_dominator_same_ctrl(old_c, barrier, u, phase) ||
1067 ShenandoahBarrierSetC2::is_shenandoah_state_load(u)) {
1068 phase->igvn().rehash_node_delayed(u);
1069 int nb = u->replace_edge(ctrl, region, &phase->igvn());
1070 if (u->is_CFG()) {
1071 if (phase->idom(u) == ctrl) {
1072 phase->set_idom(u, region, phase->dom_depth(region));
1073 }
1074 } else if (phase->get_ctrl(u) == ctrl) {
1075 assert(u != init_raw_mem, "should leave input raw mem above the barrier");
1076 uses.push(u);
1077 }
1078 assert(nb == 1, "more than 1 ctrl input?");
1079 --i, imax -= nb;
1080 }
1081 }
1082 }
1083 }
1084
1085 static Node* create_phis_on_call_return(Node* ctrl, Node* c, Node* n, Node* n_clone, const CallProjections& projs, PhaseIdealLoop* phase) {
1086 Node* region = nullptr;
1087 while (c != ctrl) {
1088 if (c->is_Region()) {
1089 region = c;
1090 }
1091 c = phase->idom(c);
1092 }
1093 assert(region != nullptr, "");
1094 Node* phi = new PhiNode(region, n->bottom_type());
1095 for (uint j = 1; j < region->req(); j++) {
1096 Node* in = region->in(j);
1097 if (phase->is_dominator(projs.fallthrough_catchproj, in)) {
1098 phi->init_req(j, n);
1099 } else if (phase->is_dominator(projs.catchall_catchproj, in)) {
1100 phi->init_req(j, n_clone);
1101 } else {
1102 phi->init_req(j, create_phis_on_call_return(ctrl, in, n, n_clone, projs, phase));
1103 }
1104 }
1105 phase->register_new_node(phi, region);
1106 return phi;
1107 }
1108
1109 void ShenandoahBarrierC2Support::pin_and_expand(PhaseIdealLoop* phase) {
1110 ShenandoahBarrierSetC2State* state = ShenandoahBarrierSetC2::bsc2()->state();
1111
1112 Unique_Node_List uses;
1113 for (int i = 0; i < state->iu_barriers_count(); i++) {
1114 Node* barrier = state->iu_barrier(i);
1115 Node* ctrl = phase->get_ctrl(barrier);
1116 IdealLoopTree* loop = phase->get_loop(ctrl);
1117 Node* head = loop->head();
1118 if (head->is_OuterStripMinedLoop()) {
1119 // Expanding a barrier here will break loop strip mining
1120 // verification. Transform the loop so the loop nest doesn't
1121 // appear as strip mined.
1122 OuterStripMinedLoopNode* outer = head->as_OuterStripMinedLoop();
1123 hide_strip_mined_loop(outer, outer->unique_ctrl_out()->as_CountedLoop(), phase);
1124 }
1125 }
1126
1127 Node_Stack stack(0);
1128 Node_List clones;
1129 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1130 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1131
1132 Node* ctrl = phase->get_ctrl(lrb);
1133 Node* val = lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
1134
1135 CallStaticJavaNode* unc = nullptr;
1136 Node* unc_ctrl = nullptr;
1137 Node* uncasted_val = val;
1138
1139 for (DUIterator_Fast imax, i = lrb->fast_outs(imax); i < imax; i++) {
1140 Node* u = lrb->fast_out(i);
1141 if (u->Opcode() == Op_CastPP &&
1142 u->in(0) != nullptr &&
1143 phase->is_dominator(u->in(0), ctrl)) {
1144 const Type* u_t = phase->igvn().type(u);
1145
1146 if (u_t->meet(TypePtr::NULL_PTR) != u_t &&
1147 u->in(0)->Opcode() == Op_IfTrue &&
1148 u->in(0)->as_Proj()->is_uncommon_trap_if_pattern() &&
1149 u->in(0)->in(0)->is_If() &&
1150 u->in(0)->in(0)->in(1)->Opcode() == Op_Bool &&
1151 u->in(0)->in(0)->in(1)->as_Bool()->_test._test == BoolTest::ne &&
1152 u->in(0)->in(0)->in(1)->in(1)->Opcode() == Op_CmpP &&
1153 u->in(0)->in(0)->in(1)->in(1)->in(1) == val &&
1154 u->in(0)->in(0)->in(1)->in(1)->in(2)->bottom_type() == TypePtr::NULL_PTR) {
1155 IdealLoopTree* loop = phase->get_loop(ctrl);
1156 IdealLoopTree* unc_loop = phase->get_loop(u->in(0));
1157
1158 if (!unc_loop->is_member(loop)) {
1159 continue;
1160 }
1161
1162 Node* branch = no_branches(ctrl, u->in(0), false, phase);
1163 assert(branch == nullptr || branch == NodeSentinel, "was not looking for a branch");
1164 if (branch == NodeSentinel) {
1165 continue;
1166 }
1167
1168 Node* iff = u->in(0)->in(0);
1169 Node* bol = iff->in(1)->clone();
1170 Node* cmp = bol->in(1)->clone();
1171 cmp->set_req(1, lrb);
1172 bol->set_req(1, cmp);
1173 phase->igvn().replace_input_of(iff, 1, bol);
1174 phase->set_ctrl(lrb, iff->in(0));
1175 phase->register_new_node(cmp, iff->in(0));
1176 phase->register_new_node(bol, iff->in(0));
1177 break;
1178 }
1179 }
1180 }
1181 if ((ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) || ctrl->is_CallJava()) {
1182 CallNode* call = ctrl->is_Proj() ? ctrl->in(0)->as_CallJava() : ctrl->as_CallJava();
1183 if (call->entry_point() == OptoRuntime::rethrow_stub()) {
1184 // The rethrow call may have too many projections to be
1185 // properly handled here. Given there's no reason for a
1186 // barrier to depend on the call, move it above the call
1187 stack.push(lrb, 0);
1188 do {
1189 Node* n = stack.node();
1190 uint idx = stack.index();
1191 if (idx < n->req()) {
1192 Node* in = n->in(idx);
1193 stack.set_index(idx+1);
1194 if (in != nullptr) {
1195 if (phase->has_ctrl(in)) {
1196 if (phase->is_dominator(call, phase->get_ctrl(in))) {
1197 #ifdef ASSERT
1198 for (uint i = 0; i < stack.size(); i++) {
1199 assert(stack.node_at(i) != in, "node shouldn't have been seen yet");
1200 }
1201 #endif
1202 stack.push(in, 0);
1203 }
1204 } else {
1205 assert(phase->is_dominator(in, call->in(0)), "no dependency on the call");
1206 }
1207 }
1208 } else {
1209 phase->set_ctrl(n, call->in(0));
1210 stack.pop();
1211 }
1212 } while(stack.size() > 0);
1213 continue;
1214 }
1215 CallProjections projs;
1216 call->extract_projections(&projs, false, false);
1217
1218 #ifdef ASSERT
1219 VectorSet cloned;
1220 #endif
1221 Node* lrb_clone = lrb->clone();
1222 phase->register_new_node(lrb_clone, projs.catchall_catchproj);
1223 phase->set_ctrl(lrb, projs.fallthrough_catchproj);
1224
1225 stack.push(lrb, 0);
1226 clones.push(lrb_clone);
1227
1228 do {
1229 assert(stack.size() == clones.size(), "");
1230 Node* n = stack.node();
1231 #ifdef ASSERT
1232 if (n->is_Load()) {
1233 Node* mem = n->in(MemNode::Memory);
1234 for (DUIterator_Fast jmax, j = mem->fast_outs(jmax); j < jmax; j++) {
1235 Node* u = mem->fast_out(j);
1236 assert(!u->is_Store() || !u->is_LoadStore() || phase->get_ctrl(u) != ctrl, "anti dependent store?");
1237 }
1238 }
1239 #endif
1240 uint idx = stack.index();
1241 Node* n_clone = clones.at(clones.size()-1);
1242 if (idx < n->outcnt()) {
1243 Node* u = n->raw_out(idx);
1244 Node* c = phase->ctrl_or_self(u);
1245 if (phase->is_dominator(call, c) && phase->is_dominator(c, projs.fallthrough_proj)) {
1246 stack.set_index(idx+1);
1247 assert(!u->is_CFG(), "");
1248 stack.push(u, 0);
1249 assert(!cloned.test_set(u->_idx), "only one clone");
1250 Node* u_clone = u->clone();
1251 int nb = u_clone->replace_edge(n, n_clone, &phase->igvn());
1252 assert(nb > 0, "should have replaced some uses");
1253 phase->register_new_node(u_clone, projs.catchall_catchproj);
1254 clones.push(u_clone);
1255 phase->set_ctrl(u, projs.fallthrough_catchproj);
1256 } else {
1257 bool replaced = false;
1258 if (u->is_Phi()) {
1259 for (uint k = 1; k < u->req(); k++) {
1260 if (u->in(k) == n) {
1261 if (phase->is_dominator(projs.catchall_catchproj, u->in(0)->in(k))) {
1262 phase->igvn().replace_input_of(u, k, n_clone);
1263 replaced = true;
1264 } else if (!phase->is_dominator(projs.fallthrough_catchproj, u->in(0)->in(k))) {
1265 phase->igvn().replace_input_of(u, k, create_phis_on_call_return(ctrl, u->in(0)->in(k), n, n_clone, projs, phase));
1266 replaced = true;
1267 }
1268 }
1269 }
1270 } else {
1271 if (phase->is_dominator(projs.catchall_catchproj, c)) {
1272 phase->igvn().rehash_node_delayed(u);
1273 int nb = u->replace_edge(n, n_clone, &phase->igvn());
1274 assert(nb > 0, "should have replaced some uses");
1275 replaced = true;
1276 } else if (!phase->is_dominator(projs.fallthrough_catchproj, c)) {
1277 if (u->is_If()) {
1278 // Can't break If/Bool/Cmp chain
1279 assert(n->is_Bool(), "unexpected If shape");
1280 assert(stack.node_at(stack.size()-2)->is_Cmp(), "unexpected If shape");
1281 assert(n_clone->is_Bool(), "unexpected clone");
1282 assert(clones.at(clones.size()-2)->is_Cmp(), "unexpected clone");
1283 Node* bol_clone = n->clone();
1284 Node* cmp_clone = stack.node_at(stack.size()-2)->clone();
1285 bol_clone->set_req(1, cmp_clone);
1286
1287 Node* nn = stack.node_at(stack.size()-3);
1288 Node* nn_clone = clones.at(clones.size()-3);
1289 assert(nn->Opcode() == nn_clone->Opcode(), "mismatch");
1290
1291 int nb = cmp_clone->replace_edge(nn, create_phis_on_call_return(ctrl, c, nn, nn_clone, projs, phase),
1292 &phase->igvn());
1293 assert(nb > 0, "should have replaced some uses");
1294
1295 phase->register_new_node(bol_clone, u->in(0));
1296 phase->register_new_node(cmp_clone, u->in(0));
1297
1298 phase->igvn().replace_input_of(u, 1, bol_clone);
1299
1300 } else {
1301 phase->igvn().rehash_node_delayed(u);
1302 int nb = u->replace_edge(n, create_phis_on_call_return(ctrl, c, n, n_clone, projs, phase), &phase->igvn());
1303 assert(nb > 0, "should have replaced some uses");
1304 }
1305 replaced = true;
1306 }
1307 }
1308 if (!replaced) {
1309 stack.set_index(idx+1);
1310 }
1311 }
1312 } else {
1313 stack.pop();
1314 clones.pop();
1315 }
1316 } while (stack.size() > 0);
1317 assert(stack.size() == 0 && clones.size() == 0, "");
1318 }
1319 }
1320
1321 for (int i = 0; i < state->load_reference_barriers_count(); i++) {
1322 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1323 Node* ctrl = phase->get_ctrl(lrb);
1324 IdealLoopTree* loop = phase->get_loop(ctrl);
1325 Node* head = loop->head();
1326 if (head->is_OuterStripMinedLoop()) {
1327 // Expanding a barrier here will break loop strip mining
1328 // verification. Transform the loop so the loop nest doesn't
1329 // appear as strip mined.
1330 OuterStripMinedLoopNode* outer = head->as_OuterStripMinedLoop();
1331 hide_strip_mined_loop(outer, outer->unique_ctrl_out()->as_CountedLoop(), phase);
1332 }
1333 }
1334
1335 // Expand load-reference-barriers
1336 MemoryGraphFixer fixer(Compile::AliasIdxRaw, true, phase);
1337 Unique_Node_List uses_to_ignore;
1338 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1339 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1340 uint last = phase->C->unique();
1341 Node* ctrl = phase->get_ctrl(lrb);
1342 Node* val = lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
1343
1344 Node* orig_ctrl = ctrl;
1345
1346 Node* raw_mem = fixer.find_mem(ctrl, lrb);
1347 Node* raw_mem_for_ctrl = fixer.find_mem(ctrl, nullptr);
1348
1349 IdealLoopTree *loop = phase->get_loop(ctrl);
1350
1351 Node* heap_stable_ctrl = nullptr;
1352 Node* null_ctrl = nullptr;
1353
1354 assert(val->bottom_type()->make_oopptr(), "need oop");
1355 assert(val->bottom_type()->make_oopptr()->const_oop() == nullptr, "expect non-constant");
1356
1357 enum { _heap_stable = 1, _evac_path, _not_cset, PATH_LIMIT };
1358 Node* region = new RegionNode(PATH_LIMIT);
1359 Node* val_phi = new PhiNode(region, val->bottom_type()->is_oopptr());
1360
1361 // Stable path.
1362 int flags = ShenandoahHeap::HAS_FORWARDED;
1363 if (!ShenandoahBarrierSet::is_strong_access(lrb->decorators())) {
1364 flags |= ShenandoahHeap::WEAK_ROOTS;
1365 }
1366 test_gc_state(ctrl, raw_mem, heap_stable_ctrl, phase, flags);
1367 IfNode* heap_stable_iff = heap_stable_ctrl->in(0)->as_If();
1368
1369 // Heap stable case
1370 region->init_req(_heap_stable, heap_stable_ctrl);
1371 val_phi->init_req(_heap_stable, val);
1372
1373 // Test for in-cset, unless it's a native-LRB. Native LRBs need to return null
1374 // even for non-cset objects to prevent resurrection of such objects.
1375 // Wires !in_cset(obj) to slot 2 of region and phis
1376 Node* not_cset_ctrl = nullptr;
1377 if (ShenandoahBarrierSet::is_strong_access(lrb->decorators())) {
1378 test_in_cset(ctrl, not_cset_ctrl, val, raw_mem, phase);
1379 }
1380 if (not_cset_ctrl != nullptr) {
1381 region->init_req(_not_cset, not_cset_ctrl);
1382 val_phi->init_req(_not_cset, val);
1383 } else {
1384 region->del_req(_not_cset);
1385 val_phi->del_req(_not_cset);
1386 }
1387
1388 // Resolve object when orig-value is in cset.
1389 // Make the unconditional resolve for fwdptr.
1390
1391 // Call lrb-stub and wire up that path in slots 4
1392 Node* result_mem = nullptr;
1393
1394 Node* addr;
1395 if (ShenandoahSelfFixing) {
1396 VectorSet visited;
1397 addr = get_load_addr(phase, visited, lrb);
1398 } else {
1399 addr = phase->igvn().zerocon(T_OBJECT);
1400 }
1401 if (addr->Opcode() == Op_AddP) {
1402 Node* orig_base = addr->in(AddPNode::Base);
1403 Node* base = new CheckCastPPNode(ctrl, orig_base, orig_base->bottom_type(), ConstraintCastNode::StrongDependency);
1404 phase->register_new_node(base, ctrl);
1405 if (addr->in(AddPNode::Base) == addr->in((AddPNode::Address))) {
1406 // Field access
1407 addr = addr->clone();
1408 addr->set_req(AddPNode::Base, base);
1409 addr->set_req(AddPNode::Address, base);
1410 phase->register_new_node(addr, ctrl);
1411 } else {
1412 Node* addr2 = addr->in(AddPNode::Address);
1413 if (addr2->Opcode() == Op_AddP && addr2->in(AddPNode::Base) == addr2->in(AddPNode::Address) &&
1414 addr2->in(AddPNode::Base) == orig_base) {
1415 addr2 = addr2->clone();
1416 addr2->set_req(AddPNode::Base, base);
1417 addr2->set_req(AddPNode::Address, base);
1418 phase->register_new_node(addr2, ctrl);
1419 addr = addr->clone();
1420 addr->set_req(AddPNode::Base, base);
1421 addr->set_req(AddPNode::Address, addr2);
1422 phase->register_new_node(addr, ctrl);
1423 }
1424 }
1425 }
1426 call_lrb_stub(ctrl, val, addr, lrb->decorators(), phase);
1427 region->init_req(_evac_path, ctrl);
1428 val_phi->init_req(_evac_path, val);
1429
1430 phase->register_control(region, loop, heap_stable_iff);
1431 Node* out_val = val_phi;
1432 phase->register_new_node(val_phi, region);
1433
1434 fix_ctrl(lrb, region, fixer, uses, uses_to_ignore, last, phase);
1435
1436 ctrl = orig_ctrl;
1437
1438 phase->igvn().replace_node(lrb, out_val);
1439
1440 follow_barrier_uses(out_val, ctrl, uses, phase);
1441
1442 for(uint next = 0; next < uses.size(); next++ ) {
1443 Node *n = uses.at(next);
1444 assert(phase->get_ctrl(n) == ctrl, "bad control");
1445 assert(n != raw_mem, "should leave input raw mem above the barrier");
1446 phase->set_ctrl(n, region);
1447 follow_barrier_uses(n, ctrl, uses, phase);
1448 }
1449 fixer.record_new_ctrl(ctrl, region, raw_mem, raw_mem_for_ctrl);
1450 }
1451 // Done expanding load-reference-barriers.
1452 assert(ShenandoahBarrierSetC2::bsc2()->state()->load_reference_barriers_count() == 0, "all load reference barrier nodes should have been replaced");
1453
1454 for (int i = state->iu_barriers_count() - 1; i >= 0; i--) {
1455 Node* barrier = state->iu_barrier(i);
1456 Node* pre_val = barrier->in(1);
1457
1458 if (phase->igvn().type(pre_val)->higher_equal(TypePtr::NULL_PTR)) {
1459 ShouldNotReachHere();
1460 continue;
1461 }
1462
1463 Node* ctrl = phase->get_ctrl(barrier);
1464
1465 if (ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) {
1466 assert(is_dominator(phase->get_ctrl(pre_val), ctrl->in(0)->in(0), pre_val, ctrl->in(0), phase), "can't move");
1467 ctrl = ctrl->in(0)->in(0);
1468 phase->set_ctrl(barrier, ctrl);
1469 } else if (ctrl->is_CallRuntime()) {
1470 assert(is_dominator(phase->get_ctrl(pre_val), ctrl->in(0), pre_val, ctrl, phase), "can't move");
1471 ctrl = ctrl->in(0);
1472 phase->set_ctrl(barrier, ctrl);
1473 }
1474
1475 Node* init_ctrl = ctrl;
1476 IdealLoopTree* loop = phase->get_loop(ctrl);
1477 Node* raw_mem = fixer.find_mem(ctrl, barrier);
1478 Node* init_raw_mem = raw_mem;
1479 Node* raw_mem_for_ctrl = fixer.find_mem(ctrl, nullptr);
1480 Node* heap_stable_ctrl = nullptr;
1481 Node* null_ctrl = nullptr;
1482 uint last = phase->C->unique();
1483
1484 enum { _heap_stable = 1, _heap_unstable, PATH_LIMIT };
1485 Node* region = new RegionNode(PATH_LIMIT);
1486 Node* phi = PhiNode::make(region, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
1487
1488 enum { _fast_path = 1, _slow_path, _null_path, PATH_LIMIT2 };
1489 Node* region2 = new RegionNode(PATH_LIMIT2);
1490 Node* phi2 = PhiNode::make(region2, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
1491
1492 // Stable path.
1493 test_gc_state(ctrl, raw_mem, heap_stable_ctrl, phase, ShenandoahHeap::MARKING);
1494 region->init_req(_heap_stable, heap_stable_ctrl);
1495 phi->init_req(_heap_stable, raw_mem);
1496
1497 // Null path
1498 Node* reg2_ctrl = nullptr;
1499 test_null(ctrl, pre_val, null_ctrl, phase);
1500 if (null_ctrl != nullptr) {
1501 reg2_ctrl = null_ctrl->in(0);
1502 region2->init_req(_null_path, null_ctrl);
1503 phi2->init_req(_null_path, raw_mem);
1504 } else {
1505 region2->del_req(_null_path);
1506 phi2->del_req(_null_path);
1507 }
1508
1509 const int index_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset());
1510 const int buffer_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset());
1511 Node* thread = new ThreadLocalNode();
1512 phase->register_new_node(thread, ctrl);
1513 Node* buffer_adr = new AddPNode(phase->C->top(), thread, phase->igvn().MakeConX(buffer_offset));
1514 phase->register_new_node(buffer_adr, ctrl);
1515 Node* index_adr = new AddPNode(phase->C->top(), thread, phase->igvn().MakeConX(index_offset));
1516 phase->register_new_node(index_adr, ctrl);
1517
1518 BasicType index_bt = TypeX_X->basic_type();
1519 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading Shenandoah SATBMarkQueue::_index with wrong size.");
1520 const TypePtr* adr_type = TypeRawPtr::BOTTOM;
1521 Node* index = new LoadXNode(ctrl, raw_mem, index_adr, adr_type, TypeX_X, MemNode::unordered);
1522 phase->register_new_node(index, ctrl);
1523 Node* index_cmp = new CmpXNode(index, phase->igvn().MakeConX(0));
1524 phase->register_new_node(index_cmp, ctrl);
1525 Node* index_test = new BoolNode(index_cmp, BoolTest::ne);
1526 phase->register_new_node(index_test, ctrl);
1527 IfNode* queue_full_iff = new IfNode(ctrl, index_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
1528 if (reg2_ctrl == nullptr) reg2_ctrl = queue_full_iff;
1529 phase->register_control(queue_full_iff, loop, ctrl);
1530 Node* not_full = new IfTrueNode(queue_full_iff);
1531 phase->register_control(not_full, loop, queue_full_iff);
1532 Node* full = new IfFalseNode(queue_full_iff);
1533 phase->register_control(full, loop, queue_full_iff);
1534
1535 ctrl = not_full;
1536
1537 Node* next_index = new SubXNode(index, phase->igvn().MakeConX(sizeof(intptr_t)));
1538 phase->register_new_node(next_index, ctrl);
1539
1540 Node* buffer = new LoadPNode(ctrl, raw_mem, buffer_adr, adr_type, TypeRawPtr::NOTNULL, MemNode::unordered);
1541 phase->register_new_node(buffer, ctrl);
1542 Node *log_addr = new AddPNode(phase->C->top(), buffer, next_index);
1543 phase->register_new_node(log_addr, ctrl);
1544 Node* log_store = new StorePNode(ctrl, raw_mem, log_addr, adr_type, pre_val, MemNode::unordered);
1545 phase->register_new_node(log_store, ctrl);
1546 // update the index
1547 Node* index_update = new StoreXNode(ctrl, log_store, index_adr, adr_type, next_index, MemNode::unordered);
1548 phase->register_new_node(index_update, ctrl);
1549
1550 // Fast-path case
1551 region2->init_req(_fast_path, ctrl);
1552 phi2->init_req(_fast_path, index_update);
1553
1554 ctrl = full;
1555
1556 Node* base = find_bottom_mem(ctrl, phase);
1557
1558 MergeMemNode* mm = MergeMemNode::make(base);
1559 mm->set_memory_at(Compile::AliasIdxRaw, raw_mem);
1560 phase->register_new_node(mm, ctrl);
1561
1562 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);
1563 call->init_req(TypeFunc::Control, ctrl);
1564 call->init_req(TypeFunc::I_O, phase->C->top());
1565 call->init_req(TypeFunc::Memory, mm);
1566 call->init_req(TypeFunc::FramePtr, phase->C->top());
1567 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
1568 call->init_req(TypeFunc::Parms, pre_val);
1569 call->init_req(TypeFunc::Parms+1, thread);
1570 phase->register_control(call, loop, ctrl);
1571
1572 Node* ctrl_proj = new ProjNode(call, TypeFunc::Control);
1573 phase->register_control(ctrl_proj, loop, call);
1574 Node* mem_proj = new ProjNode(call, TypeFunc::Memory);
1575 phase->register_new_node(mem_proj, call);
1576
1577 // Slow-path case
1578 region2->init_req(_slow_path, ctrl_proj);
1579 phi2->init_req(_slow_path, mem_proj);
1580
1581 phase->register_control(region2, loop, reg2_ctrl);
1582 phase->register_new_node(phi2, region2);
1583
1584 region->init_req(_heap_unstable, region2);
1585 phi->init_req(_heap_unstable, phi2);
1586
1587 phase->register_control(region, loop, heap_stable_ctrl->in(0));
1588 phase->register_new_node(phi, region);
1589
1590 fix_ctrl(barrier, region, fixer, uses, uses_to_ignore, last, phase);
1591 for(uint next = 0; next < uses.size(); next++ ) {
1592 Node *n = uses.at(next);
1593 assert(phase->get_ctrl(n) == init_ctrl, "bad control");
1594 assert(n != init_raw_mem, "should leave input raw mem above the barrier");
1595 phase->set_ctrl(n, region);
1596 follow_barrier_uses(n, init_ctrl, uses, phase);
1597 }
1598 fixer.fix_mem(init_ctrl, region, init_raw_mem, raw_mem_for_ctrl, phi, uses);
1599
1600 phase->igvn().replace_node(barrier, pre_val);
1601 }
1602 assert(state->iu_barriers_count() == 0, "all enqueue barrier nodes should have been replaced");
1603
1604 }
1605
1606 Node* ShenandoahBarrierC2Support::get_load_addr(PhaseIdealLoop* phase, VectorSet& visited, Node* in) {
1607 if (visited.test_set(in->_idx)) {
1608 return nullptr;
1609 }
1610 switch (in->Opcode()) {
1611 case Op_Proj:
1612 return get_load_addr(phase, visited, in->in(0));
1613 case Op_CastPP:
1614 case Op_CheckCastPP:
1615 case Op_DecodeN:
1616 case Op_EncodeP:
1617 return get_load_addr(phase, visited, in->in(1));
1618 case Op_LoadN:
1619 case Op_LoadP:
1620 return in->in(MemNode::Address);
1621 case Op_CompareAndExchangeN:
1622 case Op_CompareAndExchangeP:
1623 case Op_GetAndSetN:
1624 case Op_GetAndSetP:
1625 case Op_ShenandoahCompareAndExchangeP:
1626 case Op_ShenandoahCompareAndExchangeN:
1627 // Those instructions would just have stored a different
1628 // value into the field. No use to attempt to fix it at this point.
1629 return phase->igvn().zerocon(T_OBJECT);
1630 case Op_CMoveP:
1631 case Op_CMoveN: {
1632 Node* t = get_load_addr(phase, visited, in->in(CMoveNode::IfTrue));
1633 Node* f = get_load_addr(phase, visited, in->in(CMoveNode::IfFalse));
1634 // Handle unambiguous cases: single address reported on both branches.
1635 if (t != nullptr && f == nullptr) return t;
1636 if (t == nullptr && f != nullptr) return f;
1637 if (t != nullptr && t == f) return t;
1638 // Ambiguity.
1639 return phase->igvn().zerocon(T_OBJECT);
1640 }
1641 case Op_Phi: {
1642 Node* addr = nullptr;
1643 for (uint i = 1; i < in->req(); i++) {
1644 Node* addr1 = get_load_addr(phase, visited, in->in(i));
1645 if (addr == nullptr) {
1646 addr = addr1;
1647 }
1648 if (addr != addr1) {
1649 return phase->igvn().zerocon(T_OBJECT);
1650 }
1651 }
1652 return addr;
1653 }
1654 case Op_ShenandoahLoadReferenceBarrier:
1655 return get_load_addr(phase, visited, in->in(ShenandoahLoadReferenceBarrierNode::ValueIn));
1656 case Op_ShenandoahIUBarrier:
1657 return get_load_addr(phase, visited, in->in(1));
1658 case Op_CallDynamicJava:
1659 case Op_CallLeaf:
1660 case Op_CallStaticJava:
1661 case Op_ConN:
1662 case Op_ConP:
1663 case Op_Parm:
1664 case Op_CreateEx:
1665 return phase->igvn().zerocon(T_OBJECT);
1666 default:
1667 #ifdef ASSERT
1668 fatal("Unknown node in get_load_addr: %s", NodeClassNames[in->Opcode()]);
1669 #endif
1670 return phase->igvn().zerocon(T_OBJECT);
1671 }
1672
1673 }
1674
1675 void ShenandoahBarrierC2Support::move_gc_state_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase) {
1676 IdealLoopTree *loop = phase->get_loop(iff);
1677 Node* loop_head = loop->_head;
1678 Node* entry_c = loop_head->in(LoopNode::EntryControl);
1679
1680 Node* bol = iff->in(1);
1681 Node* cmp = bol->in(1);
1682 Node* andi = cmp->in(1);
1683 Node* load = andi->in(1);
1684
1685 assert(is_gc_state_load(load), "broken");
1686 if (!phase->is_dominator(load->in(0), entry_c)) {
1687 Node* mem_ctrl = nullptr;
1688 Node* mem = dom_mem(load->in(MemNode::Memory), loop_head, Compile::AliasIdxRaw, mem_ctrl, phase);
1689 load = load->clone();
1690 load->set_req(MemNode::Memory, mem);
1691 load->set_req(0, entry_c);
1692 phase->register_new_node(load, entry_c);
1693 andi = andi->clone();
1694 andi->set_req(1, load);
1695 phase->register_new_node(andi, entry_c);
1696 cmp = cmp->clone();
1697 cmp->set_req(1, andi);
1698 phase->register_new_node(cmp, entry_c);
1699 bol = bol->clone();
1700 bol->set_req(1, cmp);
1701 phase->register_new_node(bol, entry_c);
1702
1703 phase->igvn().replace_input_of(iff, 1, bol);
1704 }
1705 }
1706
1707 bool ShenandoahBarrierC2Support::identical_backtoback_ifs(Node* n, PhaseIdealLoop* phase) {
1708 if (!n->is_If() || n->is_CountedLoopEnd()) {
1709 return false;
1710 }
1711 Node* region = n->in(0);
1712
1713 if (!region->is_Region()) {
1714 return false;
1715 }
1716 Node* dom = phase->idom(region);
1717 if (!dom->is_If()) {
1718 return false;
1719 }
1720
1721 if (!is_heap_stable_test(n) || !is_heap_stable_test(dom)) {
1722 return false;
1723 }
1724
1725 IfNode* dom_if = dom->as_If();
1726 Node* proj_true = dom_if->proj_out(1);
1727 Node* proj_false = dom_if->proj_out(0);
1728
1729 for (uint i = 1; i < region->req(); i++) {
1730 if (phase->is_dominator(proj_true, region->in(i))) {
1731 continue;
1732 }
1733 if (phase->is_dominator(proj_false, region->in(i))) {
1734 continue;
1735 }
1736 return false;
1737 }
1738
1739 return true;
1740 }
1741
1742 void ShenandoahBarrierC2Support::merge_back_to_back_tests(Node* n, PhaseIdealLoop* phase) {
1743 assert(is_heap_stable_test(n), "no other tests");
1744 if (identical_backtoback_ifs(n, phase)) {
1745 Node* n_ctrl = n->in(0);
1746 if (phase->can_split_if(n_ctrl)) {
1747 IfNode* dom_if = phase->idom(n_ctrl)->as_If();
1748 if (is_heap_stable_test(n)) {
1749 Node* gc_state_load = n->in(1)->in(1)->in(1)->in(1);
1750 assert(is_gc_state_load(gc_state_load), "broken");
1751 Node* dom_gc_state_load = dom_if->in(1)->in(1)->in(1)->in(1);
1752 assert(is_gc_state_load(dom_gc_state_load), "broken");
1753 if (gc_state_load != dom_gc_state_load) {
1754 phase->igvn().replace_node(gc_state_load, dom_gc_state_load);
1755 }
1756 }
1757 PhiNode* bolphi = PhiNode::make_blank(n_ctrl, n->in(1));
1758 Node* proj_true = dom_if->proj_out(1);
1759 Node* proj_false = dom_if->proj_out(0);
1760 Node* con_true = phase->igvn().makecon(TypeInt::ONE);
1761 Node* con_false = phase->igvn().makecon(TypeInt::ZERO);
1762
1763 for (uint i = 1; i < n_ctrl->req(); i++) {
1764 if (phase->is_dominator(proj_true, n_ctrl->in(i))) {
1765 bolphi->init_req(i, con_true);
1766 } else {
1767 assert(phase->is_dominator(proj_false, n_ctrl->in(i)), "bad if");
1768 bolphi->init_req(i, con_false);
1769 }
1770 }
1771 phase->register_new_node(bolphi, n_ctrl);
1772 phase->igvn().replace_input_of(n, 1, bolphi);
1773 phase->do_split_if(n);
1774 }
1775 }
1776 }
1777
1778 IfNode* ShenandoahBarrierC2Support::find_unswitching_candidate(const IdealLoopTree* loop, PhaseIdealLoop* phase) {
1779 // Find first invariant test that doesn't exit the loop
1780 LoopNode *head = loop->_head->as_Loop();
1781 IfNode* unswitch_iff = nullptr;
1782 Node* n = head->in(LoopNode::LoopBackControl);
1783 int loop_has_sfpts = -1;
1784 while (n != head) {
1785 Node* n_dom = phase->idom(n);
1786 if (n->is_Region()) {
1787 if (n_dom->is_If()) {
1788 IfNode* iff = n_dom->as_If();
1789 if (iff->in(1)->is_Bool()) {
1790 BoolNode* bol = iff->in(1)->as_Bool();
1791 if (bol->in(1)->is_Cmp()) {
1792 // If condition is invariant and not a loop exit,
1793 // then found reason to unswitch.
1794 if (is_heap_stable_test(iff) &&
1795 (loop_has_sfpts == -1 || loop_has_sfpts == 0)) {
1796 assert(!loop->is_loop_exit(iff), "both branches should be in the loop");
1797 if (loop_has_sfpts == -1) {
1798 for(uint i = 0; i < loop->_body.size(); i++) {
1799 Node *m = loop->_body[i];
1800 if (m->is_SafePoint() && !m->is_CallLeaf()) {
1801 loop_has_sfpts = 1;
1802 break;
1803 }
1804 }
1805 if (loop_has_sfpts == -1) {
1806 loop_has_sfpts = 0;
1807 }
1808 }
1809 if (!loop_has_sfpts) {
1810 unswitch_iff = iff;
1811 }
1812 }
1813 }
1814 }
1815 }
1816 }
1817 n = n_dom;
1818 }
1819 return unswitch_iff;
1820 }
1821
1822
1823 void ShenandoahBarrierC2Support::optimize_after_expansion(VectorSet &visited, Node_Stack &stack, Node_List &old_new, PhaseIdealLoop* phase) {
1824 Node_List heap_stable_tests;
1825 stack.push(phase->C->start(), 0);
1826 do {
1827 Node* n = stack.node();
1828 uint i = stack.index();
1829
1830 if (i < n->outcnt()) {
1831 Node* u = n->raw_out(i);
1832 stack.set_index(i+1);
1833 if (!visited.test_set(u->_idx)) {
1834 stack.push(u, 0);
1835 }
1836 } else {
1837 stack.pop();
1838 if (n->is_If() && is_heap_stable_test(n)) {
1839 heap_stable_tests.push(n);
1840 }
1841 }
1842 } while (stack.size() > 0);
1843
1844 for (uint i = 0; i < heap_stable_tests.size(); i++) {
1845 Node* n = heap_stable_tests.at(i);
1846 assert(is_heap_stable_test(n), "only evacuation test");
1847 merge_back_to_back_tests(n, phase);
1848 }
1849
1850 if (!phase->C->major_progress()) {
1851 VectorSet seen;
1852 for (uint i = 0; i < heap_stable_tests.size(); i++) {
1853 Node* n = heap_stable_tests.at(i);
1854 IdealLoopTree* loop = phase->get_loop(n);
1855 if (loop != phase->ltree_root() &&
1856 loop->_child == nullptr &&
1857 !loop->_irreducible) {
1858 Node* head = loop->_head;
1859 if (head->is_Loop() &&
1860 (!head->is_CountedLoop() || head->as_CountedLoop()->is_main_loop() || head->as_CountedLoop()->is_normal_loop()) &&
1861 !seen.test_set(head->_idx)) {
1862 IfNode* iff = find_unswitching_candidate(loop, phase);
1863 if (iff != nullptr) {
1864 Node* bol = iff->in(1);
1865 if (head->as_Loop()->is_strip_mined()) {
1866 head->as_Loop()->verify_strip_mined(0);
1867 }
1868 move_gc_state_test_out_of_loop(iff, phase);
1869
1870 AutoNodeBudget node_budget(phase);
1871
1872 if (loop->policy_unswitching(phase)) {
1873 if (head->as_Loop()->is_strip_mined()) {
1874 OuterStripMinedLoopNode* outer = head->as_CountedLoop()->outer_loop();
1875 hide_strip_mined_loop(outer, head->as_CountedLoop(), phase);
1876 }
1877 phase->do_unswitching(loop, old_new);
1878 } else {
1879 // Not proceeding with unswitching. Move load back in
1880 // the loop.
1881 phase->igvn().replace_input_of(iff, 1, bol);
1882 }
1883 }
1884 }
1885 }
1886 }
1887 }
1888 }
1889
1890 ShenandoahIUBarrierNode::ShenandoahIUBarrierNode(Node* val) : Node(nullptr, val) {
1891 ShenandoahBarrierSetC2::bsc2()->state()->add_iu_barrier(this);
1892 }
1893
1894 const Type* ShenandoahIUBarrierNode::bottom_type() const {
1895 if (in(1) == nullptr || in(1)->is_top()) {
1896 return Type::TOP;
1897 }
1898 const Type* t = in(1)->bottom_type();
1899 if (t == TypePtr::NULL_PTR) {
1900 return t;
1901 }
1902 return t->is_oopptr();
1903 }
1904
1905 const Type* ShenandoahIUBarrierNode::Value(PhaseGVN* phase) const {
1906 if (in(1) == nullptr) {
1907 return Type::TOP;
1908 }
1909 const Type* t = phase->type(in(1));
1910 if (t == Type::TOP) {
1911 return Type::TOP;
1912 }
1913 if (t == TypePtr::NULL_PTR) {
1914 return t;
1915 }
1916 return t->is_oopptr();
1917 }
1918
1919 int ShenandoahIUBarrierNode::needed(Node* n) {
1920 if (n == nullptr ||
1921 n->is_Allocate() ||
1922 n->Opcode() == Op_ShenandoahIUBarrier ||
1923 n->bottom_type() == TypePtr::NULL_PTR ||
1924 (n->bottom_type()->make_oopptr() != nullptr && n->bottom_type()->make_oopptr()->const_oop() != nullptr)) {
1925 return NotNeeded;
1926 }
1927 if (n->is_Phi() ||
1928 n->is_CMove()) {
1929 return MaybeNeeded;
1930 }
1931 return Needed;
1932 }
1933
1934 Node* ShenandoahIUBarrierNode::next(Node* n) {
1935 for (;;) {
1936 if (n == nullptr) {
1937 return n;
1938 } else if (n->bottom_type() == TypePtr::NULL_PTR) {
1939 return n;
1940 } else if (n->bottom_type()->make_oopptr() != nullptr && n->bottom_type()->make_oopptr()->const_oop() != nullptr) {
1941 return n;
1942 } else if (n->is_ConstraintCast() ||
1943 n->Opcode() == Op_DecodeN ||
1944 n->Opcode() == Op_EncodeP) {
1945 n = n->in(1);
1946 } else if (n->is_Proj()) {
1947 n = n->in(0);
1948 } else {
1949 return n;
1950 }
1951 }
1952 ShouldNotReachHere();
1953 return nullptr;
1954 }
1955
1956 Node* ShenandoahIUBarrierNode::Identity(PhaseGVN* phase) {
1957 PhaseIterGVN* igvn = phase->is_IterGVN();
1958
1959 Node* n = next(in(1));
1960
1961 int cont = needed(n);
1962
1963 if (cont == NotNeeded) {
1964 return in(1);
1965 } else if (cont == MaybeNeeded) {
1966 if (igvn == nullptr) {
1967 phase->record_for_igvn(this);
1968 return this;
1969 } else {
1970 ResourceMark rm;
1971 Unique_Node_List wq;
1972 uint wq_i = 0;
1973
1974 for (;;) {
1975 if (n->is_Phi()) {
1976 for (uint i = 1; i < n->req(); i++) {
1977 Node* m = n->in(i);
1978 if (m != nullptr) {
1979 wq.push(m);
1980 }
1981 }
1982 } else {
1983 assert(n->is_CMove(), "nothing else here");
1984 Node* m = n->in(CMoveNode::IfFalse);
1985 wq.push(m);
1986 m = n->in(CMoveNode::IfTrue);
1987 wq.push(m);
1988 }
1989 Node* orig_n = nullptr;
1990 do {
1991 if (wq_i >= wq.size()) {
1992 return in(1);
1993 }
1994 n = wq.at(wq_i);
1995 wq_i++;
1996 orig_n = n;
1997 n = next(n);
1998 cont = needed(n);
1999 if (cont == Needed) {
2000 return this;
2001 }
2002 } while (cont != MaybeNeeded || (orig_n != n && wq.member(n)));
2003 }
2004 }
2005 }
2006
2007 return this;
2008 }
2009
2010 #ifdef ASSERT
2011 static bool has_never_branch(Node* root) {
2012 for (uint i = 1; i < root->req(); i++) {
2013 Node* in = root->in(i);
2014 if (in != nullptr && in->Opcode() == Op_Halt && in->in(0)->is_Proj() && in->in(0)->in(0)->is_NeverBranch()) {
2015 return true;
2016 }
2017 }
2018 return false;
2019 }
2020 #endif
2021
2022 void MemoryGraphFixer::collect_memory_nodes() {
2023 Node_Stack stack(0);
2024 VectorSet visited;
2025 Node_List regions;
2026
2027 // Walk the raw memory graph and create a mapping from CFG node to
2028 // memory node. Exclude phis for now.
2029 stack.push(_phase->C->root(), 1);
2030 do {
2031 Node* n = stack.node();
2032 int opc = n->Opcode();
2033 uint i = stack.index();
2034 if (i < n->req()) {
2035 Node* mem = nullptr;
2036 if (opc == Op_Root) {
2037 Node* in = n->in(i);
2038 int in_opc = in->Opcode();
2039 if (in_opc == Op_Return || in_opc == Op_Rethrow) {
2040 mem = in->in(TypeFunc::Memory);
2041 } else if (in_opc == Op_Halt) {
2042 if (in->in(0)->is_Region()) {
2043 Node* r = in->in(0);
2044 for (uint j = 1; j < r->req(); j++) {
2045 assert(!r->in(j)->is_NeverBranch(), "");
2046 }
2047 } else {
2048 Node* proj = in->in(0);
2049 assert(proj->is_Proj(), "");
2050 Node* in = proj->in(0);
2051 assert(in->is_CallStaticJava() || in->is_NeverBranch() || in->Opcode() == Op_Catch || proj->is_IfProj(), "");
2052 if (in->is_CallStaticJava()) {
2053 mem = in->in(TypeFunc::Memory);
2054 } else if (in->Opcode() == Op_Catch) {
2055 Node* call = in->in(0)->in(0);
2056 assert(call->is_Call(), "");
2057 mem = call->in(TypeFunc::Memory);
2058 } else if (in->is_NeverBranch()) {
2059 mem = collect_memory_for_infinite_loop(in);
2060 }
2061 }
2062 } else {
2063 #ifdef ASSERT
2064 n->dump();
2065 in->dump();
2066 #endif
2067 ShouldNotReachHere();
2068 }
2069 } else {
2070 assert(n->is_Phi() && n->bottom_type() == Type::MEMORY, "");
2071 assert(n->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(n->adr_type()) == _alias, "");
2072 mem = n->in(i);
2073 }
2074 i++;
2075 stack.set_index(i);
2076 if (mem == nullptr) {
2077 continue;
2078 }
2079 for (;;) {
2080 if (visited.test_set(mem->_idx) || mem->is_Start()) {
2081 break;
2082 }
2083 if (mem->is_Phi()) {
2084 stack.push(mem, 2);
2085 mem = mem->in(1);
2086 } else if (mem->is_Proj()) {
2087 stack.push(mem, mem->req());
2088 mem = mem->in(0);
2089 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
2090 mem = mem->in(TypeFunc::Memory);
2091 } else if (mem->is_MergeMem()) {
2092 MergeMemNode* mm = mem->as_MergeMem();
2093 mem = mm->memory_at(_alias);
2094 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
2095 assert(_alias == Compile::AliasIdxRaw, "");
2096 stack.push(mem, mem->req());
2097 mem = mem->in(MemNode::Memory);
2098 } else {
2099 #ifdef ASSERT
2100 mem->dump();
2101 #endif
2102 ShouldNotReachHere();
2103 }
2104 }
2105 } else {
2106 if (n->is_Phi()) {
2107 // Nothing
2108 } else if (!n->is_Root()) {
2109 Node* c = get_ctrl(n);
2110 _memory_nodes.map(c->_idx, n);
2111 }
2112 stack.pop();
2113 }
2114 } while(stack.is_nonempty());
2115
2116 // Iterate over CFG nodes in rpo and propagate memory state to
2117 // compute memory state at regions, creating new phis if needed.
2118 Node_List rpo_list;
2119 visited.clear();
2120 _phase->rpo(_phase->C->root(), stack, visited, rpo_list);
2121 Node* root = rpo_list.pop();
2122 assert(root == _phase->C->root(), "");
2123
2124 const bool trace = false;
2125 #ifdef ASSERT
2126 if (trace) {
2127 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2128 Node* c = rpo_list.at(i);
2129 if (_memory_nodes[c->_idx] != nullptr) {
2130 tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump();
2131 }
2132 }
2133 }
2134 #endif
2135 uint last = _phase->C->unique();
2136
2137 #ifdef ASSERT
2138 uint16_t max_depth = 0;
2139 for (LoopTreeIterator iter(_phase->ltree_root()); !iter.done(); iter.next()) {
2140 IdealLoopTree* lpt = iter.current();
2141 max_depth = MAX2(max_depth, lpt->_nest);
2142 }
2143 #endif
2144
2145 bool progress = true;
2146 int iteration = 0;
2147 Node_List dead_phis;
2148 while (progress) {
2149 progress = false;
2150 iteration++;
2151 assert(iteration <= 2+max_depth || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "");
2152 if (trace) { tty->print_cr("XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"); }
2153
2154 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2155 Node* c = rpo_list.at(i);
2156
2157 Node* prev_mem = _memory_nodes[c->_idx];
2158 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2159 Node* prev_region = regions[c->_idx];
2160 Node* unique = nullptr;
2161 for (uint j = 1; j < c->req() && unique != NodeSentinel; j++) {
2162 Node* m = _memory_nodes[c->in(j)->_idx];
2163 assert(m != nullptr || (c->is_Loop() && j == LoopNode::LoopBackControl && iteration == 1) || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "expect memory state");
2164 if (m != nullptr) {
2165 if (m == prev_region && ((c->is_Loop() && j == LoopNode::LoopBackControl) || (prev_region->is_Phi() && prev_region->in(0) == c))) {
2166 assert(c->is_Loop() && j == LoopNode::LoopBackControl || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "");
2167 // continue
2168 } else if (unique == nullptr) {
2169 unique = m;
2170 } else if (m == unique) {
2171 // continue
2172 } else {
2173 unique = NodeSentinel;
2174 }
2175 }
2176 }
2177 assert(unique != nullptr, "empty phi???");
2178 if (unique != NodeSentinel) {
2179 if (prev_region != nullptr && prev_region->is_Phi() && prev_region->in(0) == c) {
2180 dead_phis.push(prev_region);
2181 }
2182 regions.map(c->_idx, unique);
2183 } else {
2184 Node* phi = nullptr;
2185 if (prev_region != nullptr && prev_region->is_Phi() && prev_region->in(0) == c && prev_region->_idx >= last) {
2186 phi = prev_region;
2187 for (uint k = 1; k < c->req(); k++) {
2188 Node* m = _memory_nodes[c->in(k)->_idx];
2189 assert(m != nullptr, "expect memory state");
2190 phi->set_req(k, m);
2191 }
2192 } else {
2193 for (DUIterator_Fast jmax, j = c->fast_outs(jmax); j < jmax && phi == nullptr; j++) {
2194 Node* u = c->fast_out(j);
2195 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2196 (u->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(u->adr_type()) == _alias)) {
2197 phi = u;
2198 for (uint k = 1; k < c->req() && phi != nullptr; k++) {
2199 Node* m = _memory_nodes[c->in(k)->_idx];
2200 assert(m != nullptr, "expect memory state");
2201 if (u->in(k) != m) {
2202 phi = NodeSentinel;
2203 }
2204 }
2205 }
2206 }
2207 if (phi == NodeSentinel) {
2208 phi = new PhiNode(c, Type::MEMORY, _phase->C->get_adr_type(_alias));
2209 for (uint k = 1; k < c->req(); k++) {
2210 Node* m = _memory_nodes[c->in(k)->_idx];
2211 assert(m != nullptr, "expect memory state");
2212 phi->init_req(k, m);
2213 }
2214 }
2215 }
2216 if (phi != nullptr) {
2217 regions.map(c->_idx, phi);
2218 } else {
2219 assert(c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
2220 }
2221 }
2222 Node* current_region = regions[c->_idx];
2223 if (current_region != prev_region) {
2224 progress = true;
2225 if (prev_region == prev_mem) {
2226 _memory_nodes.map(c->_idx, current_region);
2227 }
2228 }
2229 } else if (prev_mem == nullptr || prev_mem->is_Phi() || ctrl_or_self(prev_mem) != c) {
2230 Node* m = _memory_nodes[_phase->idom(c)->_idx];
2231 assert(m != nullptr || c->Opcode() == Op_Halt, "expect memory state");
2232 if (m != prev_mem) {
2233 _memory_nodes.map(c->_idx, m);
2234 progress = true;
2235 }
2236 }
2237 #ifdef ASSERT
2238 if (trace) { tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump(); }
2239 #endif
2240 }
2241 }
2242
2243 // Replace existing phi with computed memory state for that region
2244 // if different (could be a new phi or a dominating memory node if
2245 // that phi was found to be useless).
2246 while (dead_phis.size() > 0) {
2247 Node* n = dead_phis.pop();
2248 n->replace_by(_phase->C->top());
2249 n->destruct(&_phase->igvn());
2250 }
2251 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2252 Node* c = rpo_list.at(i);
2253 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2254 Node* n = regions[c->_idx];
2255 assert(n != nullptr || c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
2256 if (n != nullptr && n->is_Phi() && n->_idx >= last && n->in(0) == c) {
2257 _phase->register_new_node(n, c);
2258 }
2259 }
2260 }
2261 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2262 Node* c = rpo_list.at(i);
2263 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2264 Node* n = regions[c->_idx];
2265 assert(n != nullptr || c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
2266 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
2267 Node* u = c->fast_out(i);
2268 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2269 u != n) {
2270 assert(c->unique_ctrl_out()->Opcode() != Op_Halt, "expected memory state");
2271 if (u->adr_type() == TypePtr::BOTTOM) {
2272 fix_memory_uses(u, n, n, c);
2273 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2274 _phase->lazy_replace(u, n);
2275 --i; --imax;
2276 }
2277 }
2278 }
2279 }
2280 }
2281 }
2282
2283 Node* MemoryGraphFixer::collect_memory_for_infinite_loop(const Node* in) {
2284 Node* mem = nullptr;
2285 Node* head = in->in(0);
2286 assert(head->is_Region(), "unexpected infinite loop graph shape");
2287
2288 Node* phi_mem = nullptr;
2289 for (DUIterator_Fast jmax, j = head->fast_outs(jmax); j < jmax; j++) {
2290 Node* u = head->fast_out(j);
2291 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
2292 if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2293 assert(phi_mem == nullptr || phi_mem->adr_type() == TypePtr::BOTTOM, "");
2294 phi_mem = u;
2295 } else if (u->adr_type() == TypePtr::BOTTOM) {
2296 assert(phi_mem == nullptr || _phase->C->get_alias_index(phi_mem->adr_type()) == _alias, "");
2297 if (phi_mem == nullptr) {
2298 phi_mem = u;
2299 }
2300 }
2301 }
2302 }
2303 if (phi_mem == nullptr) {
2304 ResourceMark rm;
2305 Node_Stack stack(0);
2306 stack.push(head, 1);
2307 do {
2308 Node* n = stack.node();
2309 uint i = stack.index();
2310 if (i >= n->req()) {
2311 stack.pop();
2312 } else {
2313 stack.set_index(i + 1);
2314 Node* c = n->in(i);
2315 assert(c != head, "should have found a safepoint on the way");
2316 if (stack.size() != 1 || _phase->is_dominator(head, c)) {
2317 for (;;) {
2318 if (c->is_Region()) {
2319 stack.push(c, 1);
2320 break;
2321 } else if (c->is_SafePoint() && !c->is_CallLeaf()) {
2322 Node* m = c->in(TypeFunc::Memory);
2323 if (m->is_MergeMem()) {
2324 m = m->as_MergeMem()->memory_at(_alias);
2325 }
2326 assert(mem == nullptr || mem == m, "several memory states");
2327 mem = m;
2328 break;
2329 } else {
2330 assert(c != c->in(0), "");
2331 c = c->in(0);
2332 }
2333 }
2334 }
2335 }
2336 } while (stack.size() > 0);
2337 assert(mem != nullptr, "should have found safepoint");
2338 } else {
2339 mem = phi_mem;
2340 }
2341 return mem;
2342 }
2343
2344 Node* MemoryGraphFixer::get_ctrl(Node* n) const {
2345 Node* c = _phase->get_ctrl(n);
2346 if (n->is_Proj() && n->in(0) != nullptr && n->in(0)->is_Call()) {
2347 assert(c == n->in(0), "");
2348 CallNode* call = c->as_Call();
2349 CallProjections projs;
2350 call->extract_projections(&projs, true, false);
2351 if (projs.catchall_memproj != nullptr) {
2352 if (projs.fallthrough_memproj == n) {
2353 c = projs.fallthrough_catchproj;
2354 } else {
2355 assert(projs.catchall_memproj == n, "");
2356 c = projs.catchall_catchproj;
2357 }
2358 }
2359 }
2360 return c;
2361 }
2362
2363 Node* MemoryGraphFixer::ctrl_or_self(Node* n) const {
2364 if (_phase->has_ctrl(n))
2365 return get_ctrl(n);
2366 else {
2367 assert (n->is_CFG(), "must be a CFG node");
2368 return n;
2369 }
2370 }
2371
2372 bool MemoryGraphFixer::mem_is_valid(Node* m, Node* c) const {
2373 return m != nullptr && get_ctrl(m) == c;
2374 }
2375
2376 Node* MemoryGraphFixer::find_mem(Node* ctrl, Node* n) const {
2377 assert(n == nullptr || _phase->ctrl_or_self(n) == ctrl, "");
2378 assert(!ctrl->is_Call() || ctrl == n, "projection expected");
2379 #ifdef ASSERT
2380 if ((ctrl->is_Proj() && ctrl->in(0)->is_Call()) ||
2381 (ctrl->is_Catch() && ctrl->in(0)->in(0)->is_Call())) {
2382 CallNode* call = ctrl->is_Proj() ? ctrl->in(0)->as_Call() : ctrl->in(0)->in(0)->as_Call();
2383 int mems = 0;
2384 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) {
2385 Node* u = call->fast_out(i);
2386 if (u->bottom_type() == Type::MEMORY) {
2387 mems++;
2388 }
2389 }
2390 assert(mems <= 1, "No node right after call if multiple mem projections");
2391 }
2392 #endif
2393 Node* mem = _memory_nodes[ctrl->_idx];
2394 Node* c = ctrl;
2395 while (!mem_is_valid(mem, c) &&
2396 (!c->is_CatchProj() || mem == nullptr || c->in(0)->in(0)->in(0) != get_ctrl(mem))) {
2397 c = _phase->idom(c);
2398 mem = _memory_nodes[c->_idx];
2399 }
2400 if (n != nullptr && mem_is_valid(mem, c)) {
2401 while (!ShenandoahBarrierC2Support::is_dominator_same_ctrl(c, mem, n, _phase) && _phase->ctrl_or_self(mem) == ctrl) {
2402 mem = next_mem(mem, _alias);
2403 }
2404 if (mem->is_MergeMem()) {
2405 mem = mem->as_MergeMem()->memory_at(_alias);
2406 }
2407 if (!mem_is_valid(mem, c)) {
2408 do {
2409 c = _phase->idom(c);
2410 mem = _memory_nodes[c->_idx];
2411 } while (!mem_is_valid(mem, c) &&
2412 (!c->is_CatchProj() || mem == nullptr || c->in(0)->in(0)->in(0) != get_ctrl(mem)));
2413 }
2414 }
2415 assert(mem->bottom_type() == Type::MEMORY, "");
2416 return mem;
2417 }
2418
2419 bool MemoryGraphFixer::has_mem_phi(Node* region) const {
2420 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
2421 Node* use = region->fast_out(i);
2422 if (use->is_Phi() && use->bottom_type() == Type::MEMORY &&
2423 (_phase->C->get_alias_index(use->adr_type()) == _alias)) {
2424 return true;
2425 }
2426 }
2427 return false;
2428 }
2429
2430 void MemoryGraphFixer::fix_mem(Node* ctrl, Node* new_ctrl, Node* mem, Node* mem_for_ctrl, Node* new_mem, Unique_Node_List& uses) {
2431 assert(_phase->ctrl_or_self(new_mem) == new_ctrl, "");
2432 const bool trace = false;
2433 DEBUG_ONLY(if (trace) { tty->print("ZZZ control is"); ctrl->dump(); });
2434 DEBUG_ONLY(if (trace) { tty->print("ZZZ mem is"); mem->dump(); });
2435 GrowableArray<Node*> phis;
2436 if (mem_for_ctrl != mem) {
2437 Node* old = mem_for_ctrl;
2438 Node* prev = nullptr;
2439 while (old != mem) {
2440 prev = old;
2441 if (old->is_Store() || old->is_ClearArray() || old->is_LoadStore()) {
2442 assert(_alias == Compile::AliasIdxRaw, "");
2443 old = old->in(MemNode::Memory);
2444 } else if (old->Opcode() == Op_SCMemProj) {
2445 assert(_alias == Compile::AliasIdxRaw, "");
2446 old = old->in(0);
2447 } else {
2448 ShouldNotReachHere();
2449 }
2450 }
2451 assert(prev != nullptr, "");
2452 if (new_ctrl != ctrl) {
2453 _memory_nodes.map(ctrl->_idx, mem);
2454 _memory_nodes.map(new_ctrl->_idx, mem_for_ctrl);
2455 }
2456 uint input = (uint)MemNode::Memory;
2457 _phase->igvn().replace_input_of(prev, input, new_mem);
2458 } else {
2459 uses.clear();
2460 _memory_nodes.map(new_ctrl->_idx, new_mem);
2461 uses.push(new_ctrl);
2462 for(uint next = 0; next < uses.size(); next++ ) {
2463 Node *n = uses.at(next);
2464 assert(n->is_CFG(), "");
2465 DEBUG_ONLY(if (trace) { tty->print("ZZZ ctrl"); n->dump(); });
2466 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2467 Node* u = n->fast_out(i);
2468 if (!u->is_Root() && u->is_CFG() && u != n) {
2469 Node* m = _memory_nodes[u->_idx];
2470 if (u->is_Region() && (!u->is_OuterStripMinedLoop() || _include_lsm) &&
2471 !has_mem_phi(u) &&
2472 u->unique_ctrl_out()->Opcode() != Op_Halt) {
2473 DEBUG_ONLY(if (trace) { tty->print("ZZZ region"); u->dump(); });
2474 DEBUG_ONLY(if (trace && m != nullptr) { tty->print("ZZZ mem"); m->dump(); });
2475
2476 if (!mem_is_valid(m, u) || !m->is_Phi()) {
2477 bool push = true;
2478 bool create_phi = true;
2479 if (_phase->is_dominator(new_ctrl, u)) {
2480 create_phi = false;
2481 }
2482 if (create_phi) {
2483 Node* phi = new PhiNode(u, Type::MEMORY, _phase->C->get_adr_type(_alias));
2484 _phase->register_new_node(phi, u);
2485 phis.push(phi);
2486 DEBUG_ONLY(if (trace) { tty->print("ZZZ new phi"); phi->dump(); });
2487 if (!mem_is_valid(m, u)) {
2488 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting mem"); phi->dump(); });
2489 _memory_nodes.map(u->_idx, phi);
2490 } else {
2491 DEBUG_ONLY(if (trace) { tty->print("ZZZ NOT setting mem"); m->dump(); });
2492 for (;;) {
2493 assert(m->is_Mem() || m->is_LoadStore() || m->is_Proj(), "");
2494 Node* next = nullptr;
2495 if (m->is_Proj()) {
2496 next = m->in(0);
2497 } else {
2498 assert(m->is_Mem() || m->is_LoadStore(), "");
2499 assert(_alias == Compile::AliasIdxRaw, "");
2500 next = m->in(MemNode::Memory);
2501 }
2502 if (_phase->get_ctrl(next) != u) {
2503 break;
2504 }
2505 if (next->is_MergeMem()) {
2506 assert(_phase->get_ctrl(next->as_MergeMem()->memory_at(_alias)) != u, "");
2507 break;
2508 }
2509 if (next->is_Phi()) {
2510 assert(next->adr_type() == TypePtr::BOTTOM && next->in(0) == u, "");
2511 break;
2512 }
2513 m = next;
2514 }
2515
2516 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting to phi"); m->dump(); });
2517 assert(m->is_Mem() || m->is_LoadStore(), "");
2518 uint input = (uint)MemNode::Memory;
2519 _phase->igvn().replace_input_of(m, input, phi);
2520 push = false;
2521 }
2522 } else {
2523 DEBUG_ONLY(if (trace) { tty->print("ZZZ skipping region"); u->dump(); });
2524 }
2525 if (push) {
2526 uses.push(u);
2527 }
2528 }
2529 } else if (!mem_is_valid(m, u) &&
2530 !(u->Opcode() == Op_CProj && u->in(0)->is_NeverBranch() && u->as_Proj()->_con == 1)) {
2531 uses.push(u);
2532 }
2533 }
2534 }
2535 }
2536 for (int i = 0; i < phis.length(); i++) {
2537 Node* n = phis.at(i);
2538 Node* r = n->in(0);
2539 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi"); n->dump(); });
2540 for (uint j = 1; j < n->req(); j++) {
2541 Node* m = find_mem(r->in(j), nullptr);
2542 _phase->igvn().replace_input_of(n, j, m);
2543 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi: %d", j); m->dump(); });
2544 }
2545 }
2546 }
2547 uint last = _phase->C->unique();
2548 MergeMemNode* mm = nullptr;
2549 int alias = _alias;
2550 DEBUG_ONLY(if (trace) { tty->print("ZZZ raw mem is"); mem->dump(); });
2551 // Process loads first to not miss an anti-dependency: if the memory
2552 // edge of a store is updated before a load is processed then an
2553 // anti-dependency may be missed.
2554 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2555 Node* u = mem->out(i);
2556 if (u->_idx < last && u->is_Load() && _phase->C->get_alias_index(u->adr_type()) == alias) {
2557 Node* m = find_mem(_phase->get_ctrl(u), u);
2558 if (m != mem) {
2559 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2560 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2561 --i;
2562 }
2563 }
2564 }
2565 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2566 Node* u = mem->out(i);
2567 if (u->_idx < last) {
2568 if (u->is_Mem()) {
2569 if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2570 Node* m = find_mem(_phase->get_ctrl(u), u);
2571 if (m != mem) {
2572 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2573 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2574 --i;
2575 }
2576 }
2577 } else if (u->is_MergeMem()) {
2578 MergeMemNode* u_mm = u->as_MergeMem();
2579 if (u_mm->memory_at(alias) == mem) {
2580 MergeMemNode* newmm = nullptr;
2581 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2582 Node* uu = u->fast_out(j);
2583 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2584 if (uu->is_Phi()) {
2585 assert(uu->adr_type() == TypePtr::BOTTOM, "");
2586 Node* region = uu->in(0);
2587 int nb = 0;
2588 for (uint k = 1; k < uu->req(); k++) {
2589 if (uu->in(k) == u) {
2590 Node* m = find_mem(region->in(k), nullptr);
2591 if (m != mem) {
2592 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", k); uu->dump(); });
2593 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2594 if (newmm != u) {
2595 _phase->igvn().replace_input_of(uu, k, newmm);
2596 nb++;
2597 --jmax;
2598 }
2599 }
2600 }
2601 }
2602 if (nb > 0) {
2603 --j;
2604 }
2605 } else {
2606 Node* m = find_mem(_phase->ctrl_or_self(uu), uu);
2607 if (m != mem) {
2608 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); uu->dump(); });
2609 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2610 if (newmm != u) {
2611 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2612 --j, --jmax;
2613 }
2614 }
2615 }
2616 }
2617 }
2618 } else if (u->is_Phi()) {
2619 assert(u->bottom_type() == Type::MEMORY, "what else?");
2620 if (_phase->C->get_alias_index(u->adr_type()) == alias || u->adr_type() == TypePtr::BOTTOM) {
2621 Node* region = u->in(0);
2622 bool replaced = false;
2623 for (uint j = 1; j < u->req(); j++) {
2624 if (u->in(j) == mem) {
2625 Node* m = find_mem(region->in(j), nullptr);
2626 Node* nnew = m;
2627 if (m != mem) {
2628 if (u->adr_type() == TypePtr::BOTTOM) {
2629 mm = allocate_merge_mem(mem, m, _phase->ctrl_or_self(m));
2630 nnew = mm;
2631 }
2632 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", j); u->dump(); });
2633 _phase->igvn().replace_input_of(u, j, nnew);
2634 replaced = true;
2635 }
2636 }
2637 }
2638 if (replaced) {
2639 --i;
2640 }
2641 }
2642 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2643 u->adr_type() == nullptr) {
2644 assert(u->adr_type() != nullptr ||
2645 u->Opcode() == Op_Rethrow ||
2646 u->Opcode() == Op_Return ||
2647 u->Opcode() == Op_SafePoint ||
2648 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2649 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2650 u->Opcode() == Op_CallLeaf, "");
2651 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2652 if (m != mem) {
2653 mm = allocate_merge_mem(mem, m, _phase->get_ctrl(m));
2654 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2655 --i;
2656 }
2657 } else if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2658 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2659 if (m != mem) {
2660 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2661 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2662 --i;
2663 }
2664 } else if (u->adr_type() != TypePtr::BOTTOM &&
2665 _memory_nodes[_phase->ctrl_or_self(u)->_idx] == u) {
2666 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2667 assert(m != mem, "");
2668 // u is on the wrong slice...
2669 assert(u->is_ClearArray(), "");
2670 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2671 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2672 --i;
2673 }
2674 }
2675 }
2676 #ifdef ASSERT
2677 assert(new_mem->outcnt() > 0, "");
2678 for (int i = 0; i < phis.length(); i++) {
2679 Node* n = phis.at(i);
2680 assert(n->outcnt() > 0, "new phi must have uses now");
2681 }
2682 #endif
2683 }
2684
2685 void MemoryGraphFixer::record_new_ctrl(Node* ctrl, Node* new_ctrl, Node* mem, Node* mem_for_ctrl) {
2686 if (mem_for_ctrl != mem && new_ctrl != ctrl) {
2687 _memory_nodes.map(ctrl->_idx, mem);
2688 _memory_nodes.map(new_ctrl->_idx, mem_for_ctrl);
2689 }
2690 }
2691
2692 MergeMemNode* MemoryGraphFixer::allocate_merge_mem(Node* mem, Node* rep_proj, Node* rep_ctrl) const {
2693 MergeMemNode* mm = MergeMemNode::make(mem);
2694 mm->set_memory_at(_alias, rep_proj);
2695 _phase->register_new_node(mm, rep_ctrl);
2696 return mm;
2697 }
2698
2699 MergeMemNode* MemoryGraphFixer::clone_merge_mem(Node* u, Node* mem, Node* rep_proj, Node* rep_ctrl, DUIterator& i) const {
2700 MergeMemNode* newmm = nullptr;
2701 MergeMemNode* u_mm = u->as_MergeMem();
2702 Node* c = _phase->get_ctrl(u);
2703 if (_phase->is_dominator(c, rep_ctrl)) {
2704 c = rep_ctrl;
2705 } else {
2706 assert(_phase->is_dominator(rep_ctrl, c), "one must dominate the other");
2707 }
2708 if (u->outcnt() == 1) {
2709 if (u->req() > (uint)_alias && u->in(_alias) == mem) {
2710 _phase->igvn().replace_input_of(u, _alias, rep_proj);
2711 --i;
2712 } else {
2713 _phase->igvn().rehash_node_delayed(u);
2714 u_mm->set_memory_at(_alias, rep_proj);
2715 }
2716 newmm = u_mm;
2717 _phase->set_ctrl_and_loop(u, c);
2718 } else {
2719 // can't simply clone u and then change one of its input because
2720 // it adds and then removes an edge which messes with the
2721 // DUIterator
2722 newmm = MergeMemNode::make(u_mm->base_memory());
2723 for (uint j = 0; j < u->req(); j++) {
2724 if (j < newmm->req()) {
2725 if (j == (uint)_alias) {
2726 newmm->set_req(j, rep_proj);
2727 } else if (newmm->in(j) != u->in(j)) {
2728 newmm->set_req(j, u->in(j));
2729 }
2730 } else if (j == (uint)_alias) {
2731 newmm->add_req(rep_proj);
2732 } else {
2733 newmm->add_req(u->in(j));
2734 }
2735 }
2736 if ((uint)_alias >= u->req()) {
2737 newmm->set_memory_at(_alias, rep_proj);
2738 }
2739 _phase->register_new_node(newmm, c);
2740 }
2741 return newmm;
2742 }
2743
2744 bool MemoryGraphFixer::should_process_phi(Node* phi) const {
2745 if (phi->adr_type() == TypePtr::BOTTOM) {
2746 Node* region = phi->in(0);
2747 for (DUIterator_Fast jmax, j = region->fast_outs(jmax); j < jmax; j++) {
2748 Node* uu = region->fast_out(j);
2749 if (uu->is_Phi() && uu != phi && uu->bottom_type() == Type::MEMORY && _phase->C->get_alias_index(uu->adr_type()) == _alias) {
2750 return false;
2751 }
2752 }
2753 return true;
2754 }
2755 return _phase->C->get_alias_index(phi->adr_type()) == _alias;
2756 }
2757
2758 void MemoryGraphFixer::fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl) const {
2759 uint last = _phase-> C->unique();
2760 MergeMemNode* mm = nullptr;
2761 assert(mem->bottom_type() == Type::MEMORY, "");
2762 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2763 Node* u = mem->out(i);
2764 if (u != replacement && u->_idx < last) {
2765 if (u->is_MergeMem()) {
2766 MergeMemNode* u_mm = u->as_MergeMem();
2767 if (u_mm->memory_at(_alias) == mem) {
2768 MergeMemNode* newmm = nullptr;
2769 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2770 Node* uu = u->fast_out(j);
2771 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2772 if (uu->is_Phi()) {
2773 if (should_process_phi(uu)) {
2774 Node* region = uu->in(0);
2775 int nb = 0;
2776 for (uint k = 1; k < uu->req(); k++) {
2777 if (uu->in(k) == u && _phase->is_dominator(rep_ctrl, region->in(k))) {
2778 if (newmm == nullptr) {
2779 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2780 }
2781 if (newmm != u) {
2782 _phase->igvn().replace_input_of(uu, k, newmm);
2783 nb++;
2784 --jmax;
2785 }
2786 }
2787 }
2788 if (nb > 0) {
2789 --j;
2790 }
2791 }
2792 } else {
2793 if (rep_ctrl != uu && ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(uu), replacement, uu, _phase)) {
2794 if (newmm == nullptr) {
2795 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2796 }
2797 if (newmm != u) {
2798 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2799 --j, --jmax;
2800 }
2801 }
2802 }
2803 }
2804 }
2805 } else if (u->is_Phi()) {
2806 assert(u->bottom_type() == Type::MEMORY, "what else?");
2807 Node* region = u->in(0);
2808 if (should_process_phi(u)) {
2809 bool replaced = false;
2810 for (uint j = 1; j < u->req(); j++) {
2811 if (u->in(j) == mem && _phase->is_dominator(rep_ctrl, region->in(j))) {
2812 Node* nnew = rep_proj;
2813 if (u->adr_type() == TypePtr::BOTTOM) {
2814 if (mm == nullptr) {
2815 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2816 }
2817 nnew = mm;
2818 }
2819 _phase->igvn().replace_input_of(u, j, nnew);
2820 replaced = true;
2821 }
2822 }
2823 if (replaced) {
2824 --i;
2825 }
2826
2827 }
2828 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2829 u->adr_type() == nullptr) {
2830 assert(u->adr_type() != nullptr ||
2831 u->Opcode() == Op_Rethrow ||
2832 u->Opcode() == Op_Return ||
2833 u->Opcode() == Op_SafePoint ||
2834 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2835 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2836 u->Opcode() == Op_CallLeaf, "%s", u->Name());
2837 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2838 if (mm == nullptr) {
2839 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2840 }
2841 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2842 --i;
2843 }
2844 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2845 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2846 _phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
2847 --i;
2848 }
2849 }
2850 }
2851 }
2852 }
2853
2854 ShenandoahLoadReferenceBarrierNode::ShenandoahLoadReferenceBarrierNode(Node* ctrl, Node* obj, DecoratorSet decorators)
2855 : Node(ctrl, obj), _decorators(decorators) {
2856 ShenandoahBarrierSetC2::bsc2()->state()->add_load_reference_barrier(this);
2857 }
2858
2859 DecoratorSet ShenandoahLoadReferenceBarrierNode::decorators() const {
2860 return _decorators;
2861 }
2862
2863 uint ShenandoahLoadReferenceBarrierNode::size_of() const {
2864 return sizeof(*this);
2865 }
2866
2867 static DecoratorSet mask_decorators(DecoratorSet decorators) {
2868 return decorators & (ON_STRONG_OOP_REF | ON_WEAK_OOP_REF | ON_PHANTOM_OOP_REF | ON_UNKNOWN_OOP_REF | IN_NATIVE);
2869 }
2870
2871 uint ShenandoahLoadReferenceBarrierNode::hash() const {
2872 uint hash = Node::hash();
2873 hash += mask_decorators(_decorators);
2874 return hash;
2875 }
2876
2877 bool ShenandoahLoadReferenceBarrierNode::cmp( const Node &n ) const {
2878 return Node::cmp(n) && n.Opcode() == Op_ShenandoahLoadReferenceBarrier &&
2879 mask_decorators(_decorators) == mask_decorators(((const ShenandoahLoadReferenceBarrierNode&)n)._decorators);
2880 }
2881
2882 const Type* ShenandoahLoadReferenceBarrierNode::bottom_type() const {
2883 if (in(ValueIn) == nullptr || in(ValueIn)->is_top()) {
2884 return Type::TOP;
2885 }
2886 const Type* t = in(ValueIn)->bottom_type();
2887 if (t == TypePtr::NULL_PTR) {
2888 return t;
2889 }
2890
2891 if (ShenandoahBarrierSet::is_strong_access(decorators())) {
2892 return t;
2893 }
2894
2895 return t->meet(TypePtr::NULL_PTR);
2896 }
2897
2898 const Type* ShenandoahLoadReferenceBarrierNode::Value(PhaseGVN* phase) const {
2899 // Either input is TOP ==> the result is TOP
2900 const Type *t2 = phase->type(in(ValueIn));
2901 if( t2 == Type::TOP ) return Type::TOP;
2902
2903 if (t2 == TypePtr::NULL_PTR) {
2904 return t2;
2905 }
2906
2907 if (ShenandoahBarrierSet::is_strong_access(decorators())) {
2908 return t2;
2909 }
2910
2911 return t2->meet(TypePtr::NULL_PTR);
2912 }
2913
2914 Node* ShenandoahLoadReferenceBarrierNode::Identity(PhaseGVN* phase) {
2915 Node* value = in(ValueIn);
2916 if (!needs_barrier(phase, value)) {
2917 return value;
2918 }
2919 return this;
2920 }
2921
2922 bool ShenandoahLoadReferenceBarrierNode::needs_barrier(PhaseGVN* phase, Node* n) {
2923 Unique_Node_List visited;
2924 return needs_barrier_impl(phase, n, visited);
2925 }
2926
2927 bool ShenandoahLoadReferenceBarrierNode::needs_barrier_impl(PhaseGVN* phase, Node* n, Unique_Node_List &visited) {
2928 if (n == nullptr) return false;
2929 if (visited.member(n)) {
2930 return false; // Been there.
2931 }
2932 visited.push(n);
2933
2934 if (n->is_Allocate()) {
2935 // tty->print_cr("optimize barrier on alloc");
2936 return false;
2937 }
2938 if (n->is_Call()) {
2939 // tty->print_cr("optimize barrier on call");
2940 return false;
2941 }
2942
2943 const Type* type = phase->type(n);
2944 if (type == Type::TOP) {
2945 return false;
2946 }
2947 if (type->make_ptr()->higher_equal(TypePtr::NULL_PTR)) {
2948 // tty->print_cr("optimize barrier on null");
2949 return false;
2950 }
2951 if (type->make_oopptr() && type->make_oopptr()->const_oop() != nullptr) {
2952 // tty->print_cr("optimize barrier on constant");
2953 return false;
2954 }
2955
2956 switch (n->Opcode()) {
2957 case Op_AddP:
2958 return true; // TODO: Can refine?
2959 case Op_LoadP:
2960 case Op_ShenandoahCompareAndExchangeN:
2961 case Op_ShenandoahCompareAndExchangeP:
2962 case Op_CompareAndExchangeN:
2963 case Op_CompareAndExchangeP:
2964 case Op_GetAndSetN:
2965 case Op_GetAndSetP:
2966 return true;
2967 case Op_Phi: {
2968 for (uint i = 1; i < n->req(); i++) {
2969 if (needs_barrier_impl(phase, n->in(i), visited)) return true;
2970 }
2971 return false;
2972 }
2973 case Op_CheckCastPP:
2974 case Op_CastPP:
2975 return needs_barrier_impl(phase, n->in(1), visited);
2976 case Op_Proj:
2977 return needs_barrier_impl(phase, n->in(0), visited);
2978 case Op_ShenandoahLoadReferenceBarrier:
2979 // tty->print_cr("optimize barrier on barrier");
2980 return false;
2981 case Op_Parm:
2982 // tty->print_cr("optimize barrier on input arg");
2983 return false;
2984 case Op_DecodeN:
2985 case Op_EncodeP:
2986 return needs_barrier_impl(phase, n->in(1), visited);
2987 case Op_LoadN:
2988 return true;
2989 case Op_CMoveN:
2990 case Op_CMoveP:
2991 return needs_barrier_impl(phase, n->in(2), visited) ||
2992 needs_barrier_impl(phase, n->in(3), visited);
2993 case Op_ShenandoahIUBarrier:
2994 return needs_barrier_impl(phase, n->in(1), visited);
2995 case Op_CreateEx:
2996 return false;
2997 default:
2998 break;
2999 }
3000 #ifdef ASSERT
3001 tty->print("need barrier on?: ");
3002 tty->print_cr("ins:");
3003 n->dump(2);
3004 tty->print_cr("outs:");
3005 n->dump(-2);
3006 ShouldNotReachHere();
3007 #endif
3008 return true;
3009 }