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 }
67 C->set_post_loop_opts_phase(); // now for real!
68 }
69 return true;
70 }
71
72 bool ShenandoahBarrierC2Support::is_gc_state_test(Node* iff, int mask) {
73 if (!UseShenandoahGC) {
74 return false;
75 }
76 assert(iff->is_If(), "bad input");
77 if (iff->Opcode() != Op_If) {
78 return false;
79 }
80 Node* bol = iff->in(1);
81 if (!bol->is_Bool() || bol->as_Bool()->_test._test != BoolTest::ne) {
82 return false;
83 }
84 Node* cmp = bol->in(1);
85 if (cmp->Opcode() != Op_CmpI) {
86 return false;
87 }
88 Node* in1 = cmp->in(1);
89 Node* in2 = cmp->in(2);
90 if (in2->find_int_con(-1) != 0) {
91 return false;
92 }
93 if (in1->Opcode() != Op_AndI) {
94 return false;
95 }
96 in2 = in1->in(2);
97 if (in2->find_int_con(-1) != mask) {
98 return false;
99 }
100 in1 = in1->in(1);
101
102 return is_gc_state_load(in1);
103 }
104
105 bool ShenandoahBarrierC2Support::is_heap_stable_test(Node* iff) {
106 return is_gc_state_test(iff, ShenandoahHeap::HAS_FORWARDED);
107 }
108
109 bool ShenandoahBarrierC2Support::is_gc_state_load(Node *n) {
110 if (!UseShenandoahGC) {
111 return false;
112 }
113 if (n->Opcode() != Op_LoadB && n->Opcode() != Op_LoadUB) {
114 return false;
115 }
116 Node* addp = n->in(MemNode::Address);
117 if (!addp->is_AddP()) {
118 return false;
119 }
120 Node* base = addp->in(AddPNode::Address);
121 Node* off = addp->in(AddPNode::Offset);
122 if (base->Opcode() != Op_ThreadLocal) {
123 return false;
124 }
125 if (off->find_intptr_t_con(-1) != in_bytes(ShenandoahThreadLocalData::gc_state_offset())) {
126 return false;
127 }
128 return true;
129 }
130
131 bool ShenandoahBarrierC2Support::has_safepoint_between(Node* start, Node* stop, PhaseIdealLoop *phase) {
132 assert(phase->is_dominator(stop, start), "bad inputs");
133 ResourceMark rm;
134 Unique_Node_List wq;
135 wq.push(start);
136 for (uint next = 0; next < wq.size(); next++) {
137 Node *m = wq.at(next);
138 if (m == stop) {
139 continue;
140 }
141 if (m->is_SafePoint() && !m->is_CallLeaf()) {
142 return true;
143 }
144 if (m->is_Region()) {
145 for (uint i = 1; i < m->req(); i++) {
146 wq.push(m->in(i));
147 }
148 } else {
149 wq.push(m->in(0));
150 }
151 }
152 return false;
153 }
154
155 #ifdef ASSERT
156 bool ShenandoahBarrierC2Support::verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used) {
157 assert(phis.size() == 0, "");
158
159 while (true) {
160 if (in->bottom_type() == TypePtr::NULL_PTR) {
161 if (trace) {tty->print_cr("null");}
162 } else if (!in->bottom_type()->make_ptr()->make_oopptr()) {
163 if (trace) {tty->print_cr("Non oop");}
164 } else {
165 if (in->is_ConstraintCast()) {
166 in = in->in(1);
167 continue;
168 } else if (in->is_AddP()) {
169 assert(!in->in(AddPNode::Address)->is_top(), "no raw memory access");
170 in = in->in(AddPNode::Address);
171 continue;
172 } else if (in->is_Con()) {
173 if (trace) {
174 tty->print("Found constant");
175 in->dump();
176 }
177 } else if (in->Opcode() == Op_Parm) {
178 if (trace) {
179 tty->print("Found argument");
180 }
181 } else if (in->Opcode() == Op_CreateEx) {
182 if (trace) {
183 tty->print("Found create-exception");
184 }
185 } else if (in->Opcode() == Op_LoadP && in->adr_type() == TypeRawPtr::BOTTOM) {
186 if (trace) {
187 tty->print("Found raw LoadP (OSR argument?)");
188 }
189 } else if (in->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
190 if (t == ShenandoahOopStore) {
191 uint i = 0;
192 for (; i < phis.size(); i++) {
193 Node* n = phis.node_at(i);
194 if (n->Opcode() == Op_ShenandoahIUBarrier) {
195 break;
196 }
197 }
198 if (i == phis.size()) {
199 return false;
200 }
201 }
202 barriers_used.push(in);
203 if (trace) {tty->print("Found barrier"); in->dump();}
204 } else if (in->Opcode() == Op_ShenandoahIUBarrier) {
205 if (t != ShenandoahOopStore) {
206 in = in->in(1);
207 continue;
208 }
209 if (trace) {tty->print("Found enqueue barrier"); in->dump();}
210 phis.push(in, in->req());
211 in = in->in(1);
212 continue;
213 } else if (in->is_Proj() && in->in(0)->is_Allocate()) {
214 if (trace) {
215 tty->print("Found alloc");
216 in->in(0)->dump();
217 }
218 } else if (in->is_Proj() && (in->in(0)->Opcode() == Op_CallStaticJava || in->in(0)->Opcode() == Op_CallDynamicJava)) {
219 if (trace) {
220 tty->print("Found Java call");
221 }
222 } else if (in->is_Phi()) {
223 if (!visited.test_set(in->_idx)) {
224 if (trace) {tty->print("Pushed phi:"); in->dump();}
225 phis.push(in, 2);
226 in = in->in(1);
227 continue;
228 }
229 if (trace) {tty->print("Already seen phi:"); in->dump();}
230 } else if (in->Opcode() == Op_CMoveP || in->Opcode() == Op_CMoveN) {
231 if (!visited.test_set(in->_idx)) {
232 if (trace) {tty->print("Pushed cmovep:"); in->dump();}
233 phis.push(in, CMoveNode::IfTrue);
234 in = in->in(CMoveNode::IfFalse);
235 continue;
236 }
237 if (trace) {tty->print("Already seen cmovep:"); in->dump();}
238 } else if (in->Opcode() == Op_EncodeP || in->Opcode() == Op_DecodeN) {
239 in = in->in(1);
240 continue;
241 } else {
242 return false;
243 }
244 }
245 bool cont = false;
246 while (phis.is_nonempty()) {
247 uint idx = phis.index();
248 Node* phi = phis.node();
249 if (idx >= phi->req()) {
250 if (trace) {tty->print("Popped phi:"); phi->dump();}
251 phis.pop();
252 continue;
253 }
254 if (trace) {tty->print("Next entry(%d) for phi:", idx); phi->dump();}
255 in = phi->in(idx);
256 phis.set_index(idx+1);
257 cont = true;
258 break;
259 }
260 if (!cont) {
261 break;
262 }
263 }
264 return true;
265 }
266
267 void ShenandoahBarrierC2Support::report_verify_failure(const char* msg, Node* n1, Node* n2) {
268 if (n1 != nullptr) {
269 n1->dump(+10);
270 }
271 if (n2 != nullptr) {
272 n2->dump(+10);
273 }
274 fatal("%s", msg);
275 }
276
277 void ShenandoahBarrierC2Support::verify(RootNode* root) {
278 ResourceMark rm;
279 Unique_Node_List wq;
280 GrowableArray<Node*> barriers;
281 Unique_Node_List barriers_used;
282 Node_Stack phis(0);
283 VectorSet visited;
284 const bool trace = false;
285 const bool verify_no_useless_barrier = false;
286
287 wq.push(root);
288 for (uint next = 0; next < wq.size(); next++) {
289 Node *n = wq.at(next);
290 if (n->is_Load()) {
291 const bool trace = false;
292 if (trace) {tty->print("Verifying"); n->dump();}
293 if (n->Opcode() == Op_LoadRange || n->Opcode() == Op_LoadKlass || n->Opcode() == Op_LoadNKlass) {
294 if (trace) {tty->print_cr("Load range/klass");}
295 } else {
296 const TypePtr* adr_type = n->as_Load()->adr_type();
297
298 if (adr_type->isa_oopptr() && adr_type->is_oopptr()->offset() == oopDesc::mark_offset_in_bytes()) {
299 if (trace) {tty->print_cr("Mark load");}
300 } else if (adr_type->isa_instptr() &&
301 adr_type->is_instptr()->instance_klass()->is_subtype_of(Compile::current()->env()->Reference_klass()) &&
302 adr_type->is_instptr()->offset() == java_lang_ref_Reference::referent_offset()) {
303 if (trace) {tty->print_cr("Reference.get()");}
304 } else if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahLoad, trace, barriers_used)) {
305 report_verify_failure("Shenandoah verification: Load should have barriers", n);
306 }
307 }
308 } else if (n->is_Store()) {
309 const bool trace = false;
310
311 if (trace) {tty->print("Verifying"); n->dump();}
312 if (n->in(MemNode::ValueIn)->bottom_type()->make_oopptr()) {
313 Node* adr = n->in(MemNode::Address);
314 bool verify = true;
315
316 if (adr->is_AddP() && adr->in(AddPNode::Base)->is_top()) {
317 adr = adr->in(AddPNode::Address);
318 if (adr->is_AddP()) {
319 assert(adr->in(AddPNode::Base)->is_top(), "");
320 adr = adr->in(AddPNode::Address);
321 if (adr->Opcode() == Op_LoadP &&
322 adr->in(MemNode::Address)->in(AddPNode::Base)->is_top() &&
323 adr->in(MemNode::Address)->in(AddPNode::Address)->Opcode() == Op_ThreadLocal &&
324 adr->in(MemNode::Address)->in(AddPNode::Offset)->find_intptr_t_con(-1) == in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset())) {
325 if (trace) {tty->print_cr("SATB prebarrier");}
326 verify = false;
327 }
328 }
329 }
330
331 if (verify && !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahIUBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
332 report_verify_failure("Shenandoah verification: Store should have barriers", n);
333 }
334 }
335 if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
336 report_verify_failure("Shenandoah verification: Store (address) should have barriers", n);
337 }
338 } else if (n->Opcode() == Op_CmpP) {
339 const bool trace = false;
340
341 Node* in1 = n->in(1);
342 Node* in2 = n->in(2);
343 if (in1->bottom_type()->isa_oopptr()) {
344 if (trace) {tty->print("Verifying"); n->dump();}
345
346 bool mark_inputs = false;
347 if (in1->bottom_type() == TypePtr::NULL_PTR || in2->bottom_type() == TypePtr::NULL_PTR ||
348 (in1->is_Con() || in2->is_Con())) {
349 if (trace) {tty->print_cr("Comparison against a constant");}
350 mark_inputs = true;
351 } else if ((in1->is_CheckCastPP() && in1->in(1)->is_Proj() && in1->in(1)->in(0)->is_Allocate()) ||
352 (in2->is_CheckCastPP() && in2->in(1)->is_Proj() && in2->in(1)->in(0)->is_Allocate())) {
353 if (trace) {tty->print_cr("Comparison with newly alloc'ed object");}
354 mark_inputs = true;
355 } else {
356 assert(in2->bottom_type()->isa_oopptr(), "");
357
358 if (!verify_helper(in1, phis, visited, ShenandoahStore, trace, barriers_used) ||
359 !verify_helper(in2, phis, visited, ShenandoahStore, trace, barriers_used)) {
360 report_verify_failure("Shenandoah verification: Cmp should have barriers", n);
361 }
362 }
363 if (verify_no_useless_barrier &&
364 mark_inputs &&
365 (!verify_helper(in1, phis, visited, ShenandoahValue, trace, barriers_used) ||
366 !verify_helper(in2, phis, visited, ShenandoahValue, trace, barriers_used))) {
367 phis.clear();
368 visited.reset();
369 }
370 }
371 } else if (n->is_LoadStore()) {
372 if (n->in(MemNode::ValueIn)->bottom_type()->make_ptr() &&
373 !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahIUBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
374 report_verify_failure("Shenandoah verification: LoadStore (value) should have barriers", n);
375 }
376
377 if (n->in(MemNode::Address)->bottom_type()->make_oopptr() && !verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
378 report_verify_failure("Shenandoah verification: LoadStore (address) should have barriers", n);
379 }
380 } else if (n->Opcode() == Op_CallLeafNoFP || n->Opcode() == Op_CallLeaf) {
381 CallNode* call = n->as_Call();
382
383 static struct {
384 const char* name;
385 struct {
386 int pos;
387 verify_type t;
388 } args[6];
389 } calls[] = {
390 "aescrypt_encryptBlock",
391 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
392 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
393 "aescrypt_decryptBlock",
394 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
395 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
396 "multiplyToLen",
397 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { TypeFunc::Parms+4, ShenandoahStore },
398 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
399 "squareToLen",
400 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { -1, ShenandoahNone},
401 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
402 "montgomery_multiply",
403 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
404 { TypeFunc::Parms+6, ShenandoahStore }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
405 "montgomery_square",
406 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+5, ShenandoahStore },
407 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
408 "mulAdd",
409 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
410 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
411 "vectorizedMismatch",
412 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
413 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
414 "updateBytesCRC32",
415 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
416 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
417 "updateBytesAdler32",
418 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
419 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
420 "updateBytesCRC32C",
421 { { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahLoad}, { -1, ShenandoahNone},
422 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
423 "counterMode_AESCrypt",
424 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
425 { TypeFunc::Parms+3, ShenandoahStore }, { TypeFunc::Parms+5, ShenandoahStore }, { TypeFunc::Parms+6, ShenandoahStore } },
426 "cipherBlockChaining_encryptAESCrypt",
427 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
428 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
429 "cipherBlockChaining_decryptAESCrypt",
430 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
431 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
432 "shenandoah_clone_barrier",
433 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
434 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
435 "ghash_processBlocks",
436 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
437 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
438 "sha1_implCompress",
439 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
440 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
441 "sha256_implCompress",
442 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
443 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
444 "sha512_implCompress",
445 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
446 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
447 "sha1_implCompressMB",
448 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
449 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
450 "sha256_implCompressMB",
451 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
452 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
453 "sha512_implCompressMB",
454 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
455 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
456 "encodeBlock",
457 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
458 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
459 "decodeBlock",
460 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
461 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
462 };
463
464 if (call->is_call_to_arraycopystub()) {
465 Node* dest = nullptr;
466 const TypeTuple* args = n->as_Call()->_tf->domain_sig();
467 for (uint i = TypeFunc::Parms, j = 0; i < args->cnt(); i++) {
468 if (args->field_at(i)->isa_ptr()) {
469 j++;
470 if (j == 2) {
471 dest = n->in(i);
472 break;
473 }
474 }
475 }
476 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahLoad, trace, barriers_used) ||
477 !verify_helper(dest, phis, visited, ShenandoahStore, trace, barriers_used)) {
478 report_verify_failure("Shenandoah verification: ArrayCopy should have barriers", n);
479 }
480 } else if (strlen(call->_name) > 5 &&
481 !strcmp(call->_name + strlen(call->_name) - 5, "_fill")) {
482 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahStore, trace, barriers_used)) {
483 report_verify_failure("Shenandoah verification: _fill should have barriers", n);
484 }
485 } else if (!strcmp(call->_name, "shenandoah_wb_pre")) {
486 // skip
487 } else {
488 const int calls_len = sizeof(calls) / sizeof(calls[0]);
489 int i = 0;
490 for (; i < calls_len; i++) {
491 if (!strcmp(calls[i].name, call->_name)) {
492 break;
493 }
494 }
495 if (i != calls_len) {
496 const uint args_len = sizeof(calls[0].args) / sizeof(calls[0].args[0]);
497 for (uint j = 0; j < args_len; j++) {
498 int pos = calls[i].args[j].pos;
499 if (pos == -1) {
500 break;
501 }
502 if (!verify_helper(call->in(pos), phis, visited, calls[i].args[j].t, trace, barriers_used)) {
503 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
504 }
505 }
506 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
507 if (call->in(j)->bottom_type()->make_ptr() &&
508 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
509 uint k = 0;
510 for (; k < args_len && calls[i].args[k].pos != (int)j; k++);
511 if (k == args_len) {
512 fatal("arg %d for call %s not covered", j, call->_name);
513 }
514 }
515 }
516 } else {
517 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
518 if (call->in(j)->bottom_type()->make_ptr() &&
519 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
520 fatal("%s not covered", call->_name);
521 }
522 }
523 }
524 }
525 } else if (n->Opcode() == Op_ShenandoahIUBarrier || n->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
526 // skip
527 } else if (n->is_AddP()
528 || n->is_Phi()
529 || n->is_ConstraintCast()
530 || n->Opcode() == Op_Return
531 || n->Opcode() == Op_CMoveP
532 || n->Opcode() == Op_CMoveN
533 || n->Opcode() == Op_Rethrow
534 || n->is_MemBar()
535 || n->Opcode() == Op_Conv2B
536 || n->Opcode() == Op_SafePoint
537 || n->is_CallJava()
538 || n->Opcode() == Op_Unlock
539 || n->Opcode() == Op_EncodeP
540 || n->Opcode() == Op_DecodeN) {
541 // nothing to do
542 } else {
543 static struct {
544 int opcode;
545 struct {
546 int pos;
547 verify_type t;
548 } inputs[2];
549 } others[] = {
550 Op_FastLock,
551 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
552 Op_Lock,
553 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone} },
554 Op_ArrayCopy,
555 { { ArrayCopyNode::Src, ShenandoahLoad }, { ArrayCopyNode::Dest, ShenandoahStore } },
556 Op_StrCompressedCopy,
557 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
558 Op_StrInflatedCopy,
559 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
560 Op_AryEq,
561 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
562 Op_StrIndexOf,
563 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
564 Op_StrComp,
565 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
566 Op_StrEquals,
567 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
568 Op_VectorizedHashCode,
569 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
570 Op_EncodeISOArray,
571 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
572 Op_CountPositives,
573 { { 2, ShenandoahLoad }, { -1, ShenandoahNone} },
574 Op_CastP2X,
575 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
576 Op_StrIndexOfChar,
577 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
578 };
579
580 const int others_len = sizeof(others) / sizeof(others[0]);
581 int i = 0;
582 for (; i < others_len; i++) {
583 if (others[i].opcode == n->Opcode()) {
584 break;
585 }
586 }
587 uint stop = n->is_Call() ? n->as_Call()->tf()->domain_sig()->cnt() : n->req();
588 if (i != others_len) {
589 const uint inputs_len = sizeof(others[0].inputs) / sizeof(others[0].inputs[0]);
590 for (uint j = 0; j < inputs_len; j++) {
591 int pos = others[i].inputs[j].pos;
592 if (pos == -1) {
593 break;
594 }
595 if (!verify_helper(n->in(pos), phis, visited, others[i].inputs[j].t, trace, barriers_used)) {
596 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
597 }
598 }
599 for (uint j = 1; j < stop; j++) {
600 if (n->in(j) != nullptr && n->in(j)->bottom_type()->make_ptr() &&
601 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
602 uint k = 0;
603 for (; k < inputs_len && others[i].inputs[k].pos != (int)j; k++);
604 if (k == inputs_len) {
605 fatal("arg %d for node %s not covered", j, n->Name());
606 }
607 }
608 }
609 } else {
610 for (uint j = 1; j < stop; j++) {
611 if (n->in(j) != nullptr && n->in(j)->bottom_type()->make_ptr() &&
612 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
613 fatal("%s not covered", n->Name());
614 }
615 }
616 }
617 }
618
619 if (n->is_SafePoint()) {
620 SafePointNode* sfpt = n->as_SafePoint();
621 if (verify_no_useless_barrier && sfpt->jvms() != nullptr) {
622 for (uint i = sfpt->jvms()->scloff(); i < sfpt->jvms()->endoff(); i++) {
623 if (!verify_helper(sfpt->in(i), phis, visited, ShenandoahLoad, trace, barriers_used)) {
624 phis.clear();
625 visited.reset();
626 }
627 }
628 }
629 }
630 }
631
632 if (verify_no_useless_barrier) {
633 for (int i = 0; i < barriers.length(); i++) {
634 Node* n = barriers.at(i);
635 if (!barriers_used.member(n)) {
636 tty->print("XXX useless barrier"); n->dump(-2);
637 ShouldNotReachHere();
638 }
639 }
640 }
641 }
642 #endif
643
644 bool ShenandoahBarrierC2Support::is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase) {
645 // That both nodes have the same control is not sufficient to prove
646 // domination, verify that there's no path from d to n
647 ResourceMark rm;
648 Unique_Node_List wq;
649 wq.push(d);
650 for (uint next = 0; next < wq.size(); next++) {
651 Node *m = wq.at(next);
652 if (m == n) {
653 return false;
654 }
655 if (m->is_Phi() && m->in(0)->is_Loop()) {
656 assert(phase->ctrl_or_self(m->in(LoopNode::EntryControl)) != c, "following loop entry should lead to new control");
657 } else {
658 if (m->is_Store() || m->is_LoadStore()) {
659 // Take anti-dependencies into account
660 Node* mem = m->in(MemNode::Memory);
661 for (DUIterator_Fast imax, i = mem->fast_outs(imax); i < imax; i++) {
662 Node* u = mem->fast_out(i);
663 if (u->is_Load() && phase->C->can_alias(m->adr_type(), phase->C->get_alias_index(u->adr_type())) &&
664 phase->ctrl_or_self(u) == c) {
665 wq.push(u);
666 }
667 }
668 }
669 for (uint i = 0; i < m->req(); i++) {
670 if (m->in(i) != nullptr && phase->ctrl_or_self(m->in(i)) == c) {
671 wq.push(m->in(i));
672 }
673 }
674 }
675 }
676 return true;
677 }
678
679 bool ShenandoahBarrierC2Support::is_dominator(Node* d_c, Node* n_c, Node* d, Node* n, PhaseIdealLoop* phase) {
680 if (d_c != n_c) {
681 return phase->is_dominator(d_c, n_c);
682 }
683 return is_dominator_same_ctrl(d_c, d, n, phase);
684 }
685
686 Node* next_mem(Node* mem, int alias) {
687 Node* res = nullptr;
688 if (mem->is_Proj()) {
689 res = mem->in(0);
690 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
691 res = mem->in(TypeFunc::Memory);
692 } else if (mem->is_Phi()) {
693 res = mem->in(1);
694 } else if (mem->is_MergeMem()) {
695 res = mem->as_MergeMem()->memory_at(alias);
696 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
697 assert(alias == Compile::AliasIdxRaw, "following raw memory can't lead to a barrier");
698 res = mem->in(MemNode::Memory);
699 } else {
700 #ifdef ASSERT
701 mem->dump();
702 #endif
703 ShouldNotReachHere();
704 }
705 return res;
706 }
707
708 Node* ShenandoahBarrierC2Support::no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase) {
709 Node* iffproj = nullptr;
710 while (c != dom) {
711 Node* next = phase->idom(c);
712 assert(next->unique_ctrl_out_or_null() == c || c->is_Proj() || c->is_Region(), "multiple control flow out but no proj or region?");
713 if (c->is_Region()) {
714 ResourceMark rm;
715 Unique_Node_List wq;
716 wq.push(c);
717 for (uint i = 0; i < wq.size(); i++) {
718 Node *n = wq.at(i);
719 if (n == next) {
720 continue;
721 }
722 if (n->is_Region()) {
723 for (uint j = 1; j < n->req(); j++) {
724 wq.push(n->in(j));
725 }
726 } else {
727 wq.push(n->in(0));
728 }
729 }
730 for (uint i = 0; i < wq.size(); i++) {
731 Node *n = wq.at(i);
732 assert(n->is_CFG(), "");
733 if (n->is_Multi()) {
734 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
735 Node* u = n->fast_out(j);
736 if (u->is_CFG()) {
737 if (!wq.member(u) && !u->as_Proj()->is_uncommon_trap_proj(Deoptimization::Reason_none)) {
738 return NodeSentinel;
739 }
740 }
741 }
742 }
743 }
744 } else if (c->is_Proj()) {
745 if (c->is_IfProj()) {
746 if (c->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) != nullptr) {
747 // continue;
748 } else {
749 if (!allow_one_proj) {
750 return NodeSentinel;
751 }
752 if (iffproj == nullptr) {
753 iffproj = c;
754 } else {
755 return NodeSentinel;
756 }
757 }
758 } else if (c->Opcode() == Op_JumpProj) {
759 return NodeSentinel; // unsupported
760 } else if (c->Opcode() == Op_CatchProj) {
761 return NodeSentinel; // unsupported
762 } else if (c->Opcode() == Op_CProj && next->is_NeverBranch()) {
763 return NodeSentinel; // unsupported
764 } else {
765 assert(next->unique_ctrl_out() == c, "unsupported branch pattern");
766 }
767 }
768 c = next;
769 }
770 return iffproj;
771 }
772
773 Node* ShenandoahBarrierC2Support::dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase) {
774 ResourceMark rm;
775 VectorSet wq;
776 wq.set(mem->_idx);
777 mem_ctrl = phase->ctrl_or_self(mem);
778 while (!phase->is_dominator(mem_ctrl, ctrl) || mem_ctrl == ctrl) {
779 mem = next_mem(mem, alias);
780 if (wq.test_set(mem->_idx)) {
781 return nullptr;
782 }
783 mem_ctrl = phase->ctrl_or_self(mem);
784 }
785 if (mem->is_MergeMem()) {
786 mem = mem->as_MergeMem()->memory_at(alias);
787 mem_ctrl = phase->ctrl_or_self(mem);
788 }
789 return mem;
790 }
791
792 Node* ShenandoahBarrierC2Support::find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase) {
793 Node* mem = nullptr;
794 Node* c = ctrl;
795 do {
796 if (c->is_Region()) {
797 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax && mem == nullptr; i++) {
798 Node* u = c->fast_out(i);
799 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
800 if (u->adr_type() == TypePtr::BOTTOM) {
801 mem = u;
802 }
803 }
804 }
805 } else {
806 if (c->is_Call() && c->as_Call()->adr_type() != nullptr) {
807 CallProjections* projs = c->as_Call()->extract_projections(true, false);
808 if (projs->fallthrough_memproj != nullptr) {
809 if (projs->fallthrough_memproj->adr_type() == TypePtr::BOTTOM) {
810 if (projs->catchall_memproj == nullptr) {
811 mem = projs->fallthrough_memproj;
812 } else {
813 if (phase->is_dominator(projs->fallthrough_catchproj, ctrl)) {
814 mem = projs->fallthrough_memproj;
815 } else {
816 assert(phase->is_dominator(projs->catchall_catchproj, ctrl), "one proj must dominate barrier");
817 mem = projs->catchall_memproj;
818 }
819 }
820 }
821 } else {
822 Node* proj = c->as_Call()->proj_out(TypeFunc::Memory);
823 if (proj != nullptr &&
824 proj->adr_type() == TypePtr::BOTTOM) {
825 mem = proj;
826 }
827 }
828 } else {
829 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
830 Node* u = c->fast_out(i);
831 if (u->is_Proj() &&
832 u->bottom_type() == Type::MEMORY &&
833 u->adr_type() == TypePtr::BOTTOM) {
834 assert(c->is_SafePoint() || c->is_MemBar() || c->is_Start(), "");
835 assert(mem == nullptr, "only one proj");
836 mem = u;
837 }
838 }
839 assert(!c->is_Call() || c->as_Call()->adr_type() != nullptr || mem == nullptr, "no mem projection expected");
840 }
841 }
842 c = phase->idom(c);
843 } while (mem == nullptr);
844 return mem;
845 }
846
847 void ShenandoahBarrierC2Support::follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase) {
848 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
849 Node* u = n->fast_out(i);
850 if (!u->is_CFG() && phase->get_ctrl(u) == ctrl && (!u->is_Phi() || !u->in(0)->is_Loop() || u->in(LoopNode::LoopBackControl) != n)) {
851 uses.push(u);
852 }
853 }
854 }
855
856 static void hide_strip_mined_loop(OuterStripMinedLoopNode* outer, CountedLoopNode* inner, PhaseIdealLoop* phase) {
857 OuterStripMinedLoopEndNode* le = inner->outer_loop_end();
858 Node* new_outer = new LoopNode(outer->in(LoopNode::EntryControl), outer->in(LoopNode::LoopBackControl));
859 phase->register_control(new_outer, phase->get_loop(outer), outer->in(LoopNode::EntryControl));
860 Node* new_le = new IfNode(le->in(0), le->in(1), le->_prob, le->_fcnt);
861 phase->register_control(new_le, phase->get_loop(le), le->in(0));
862 phase->lazy_replace(outer, new_outer);
863 phase->lazy_replace(le, new_le);
864 inner->clear_strip_mined();
865 }
866
867 void ShenandoahBarrierC2Support::test_gc_state(Node*& ctrl, Node* raw_mem, Node*& test_fail_ctrl,
868 PhaseIdealLoop* phase, int flags) {
869 PhaseIterGVN& igvn = phase->igvn();
870 Node* old_ctrl = ctrl;
871
872 Node* thread = new ThreadLocalNode();
873 Node* gc_state_offset = igvn.MakeConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
874 Node* gc_state_addr = new AddPNode(phase->C->top(), thread, gc_state_offset);
875 Node* gc_state = new LoadBNode(old_ctrl, raw_mem, gc_state_addr,
876 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(nullptr),
877 TypeInt::BYTE, MemNode::unordered);
878 Node* gc_state_and = new AndINode(gc_state, igvn.intcon(flags));
879 Node* gc_state_cmp = new CmpINode(gc_state_and, igvn.zerocon(T_INT));
880 Node* gc_state_bool = new BoolNode(gc_state_cmp, BoolTest::ne);
881
882 IfNode* gc_state_iff = new IfNode(old_ctrl, gc_state_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
883 ctrl = new IfTrueNode(gc_state_iff);
884 test_fail_ctrl = new IfFalseNode(gc_state_iff);
885
886 IdealLoopTree* loop = phase->get_loop(old_ctrl);
887 phase->register_control(gc_state_iff, loop, old_ctrl);
888 phase->register_control(ctrl, loop, gc_state_iff);
889 phase->register_control(test_fail_ctrl, loop, gc_state_iff);
890
891 phase->register_new_node(thread, old_ctrl);
892 phase->register_new_node(gc_state_addr, old_ctrl);
893 phase->register_new_node(gc_state, old_ctrl);
894 phase->register_new_node(gc_state_and, old_ctrl);
895 phase->register_new_node(gc_state_cmp, old_ctrl);
896 phase->register_new_node(gc_state_bool, old_ctrl);
897
898 phase->set_ctrl(gc_state_offset, phase->C->root());
899
900 assert(is_gc_state_test(gc_state_iff, flags), "Should match the shape");
901 }
902
903 void ShenandoahBarrierC2Support::test_null(Node*& ctrl, Node* val, Node*& null_ctrl, PhaseIdealLoop* phase) {
904 Node* old_ctrl = ctrl;
905 PhaseIterGVN& igvn = phase->igvn();
906
907 const Type* val_t = igvn.type(val);
908 if (val_t->meet(TypePtr::NULL_PTR) == val_t) {
909 Node* null_cmp = new CmpPNode(val, igvn.zerocon(T_OBJECT));
910 Node* null_test = new BoolNode(null_cmp, BoolTest::ne);
911
912 IfNode* null_iff = new IfNode(old_ctrl, null_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
913 ctrl = new IfTrueNode(null_iff);
914 null_ctrl = new IfFalseNode(null_iff);
915
916 IdealLoopTree* loop = phase->get_loop(old_ctrl);
917 phase->register_control(null_iff, loop, old_ctrl);
918 phase->register_control(ctrl, loop, null_iff);
919 phase->register_control(null_ctrl, loop, null_iff);
920
921 phase->register_new_node(null_cmp, old_ctrl);
922 phase->register_new_node(null_test, old_ctrl);
923 }
924 }
925
926 void ShenandoahBarrierC2Support::test_in_cset(Node*& ctrl, Node*& not_cset_ctrl, Node* val, Node* raw_mem, PhaseIdealLoop* phase) {
927 Node* old_ctrl = ctrl;
928 PhaseIterGVN& igvn = phase->igvn();
929
930 Node* raw_val = new CastP2XNode(old_ctrl, val);
931 Node* cset_idx = new URShiftXNode(raw_val, igvn.intcon(ShenandoahHeapRegion::region_size_bytes_shift_jint()));
932
933 // Figure out the target cset address with raw pointer math.
934 // This avoids matching AddP+LoadB that would emit inefficient code.
935 // See JDK-8245465.
936 Node* cset_addr_ptr = igvn.makecon(TypeRawPtr::make(ShenandoahHeap::in_cset_fast_test_addr()));
937 Node* cset_addr = new CastP2XNode(old_ctrl, cset_addr_ptr);
938 Node* cset_load_addr = new AddXNode(cset_addr, cset_idx);
939 Node* cset_load_ptr = new CastX2PNode(cset_load_addr);
940
941 Node* cset_load = new LoadBNode(old_ctrl, raw_mem, cset_load_ptr,
942 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(nullptr),
943 TypeInt::BYTE, MemNode::unordered);
944 Node* cset_cmp = new CmpINode(cset_load, igvn.zerocon(T_INT));
945 Node* cset_bool = new BoolNode(cset_cmp, BoolTest::ne);
946
947 IfNode* cset_iff = new IfNode(old_ctrl, cset_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
948 ctrl = new IfTrueNode(cset_iff);
949 not_cset_ctrl = new IfFalseNode(cset_iff);
950
951 IdealLoopTree *loop = phase->get_loop(old_ctrl);
952 phase->register_control(cset_iff, loop, old_ctrl);
953 phase->register_control(ctrl, loop, cset_iff);
954 phase->register_control(not_cset_ctrl, loop, cset_iff);
955
956 phase->set_ctrl(cset_addr_ptr, phase->C->root());
957
958 phase->register_new_node(raw_val, old_ctrl);
959 phase->register_new_node(cset_idx, old_ctrl);
960 phase->register_new_node(cset_addr, old_ctrl);
961 phase->register_new_node(cset_load_addr, old_ctrl);
962 phase->register_new_node(cset_load_ptr, old_ctrl);
963 phase->register_new_node(cset_load, old_ctrl);
964 phase->register_new_node(cset_cmp, old_ctrl);
965 phase->register_new_node(cset_bool, old_ctrl);
966 }
967
968 void ShenandoahBarrierC2Support::call_lrb_stub(Node*& ctrl, Node*& val, Node* load_addr,
969 DecoratorSet decorators, PhaseIdealLoop* phase) {
970 IdealLoopTree*loop = phase->get_loop(ctrl);
971 const TypePtr* obj_type = phase->igvn().type(val)->is_oopptr();
972
973 address calladdr = nullptr;
974 const char* name = nullptr;
975 bool is_strong = ShenandoahBarrierSet::is_strong_access(decorators);
976 bool is_weak = ShenandoahBarrierSet::is_weak_access(decorators);
977 bool is_phantom = ShenandoahBarrierSet::is_phantom_access(decorators);
978 bool is_native = ShenandoahBarrierSet::is_native_access(decorators);
979 bool is_narrow = UseCompressedOops && !is_native;
980 if (is_strong) {
981 if (is_narrow) {
982 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong_narrow);
983 name = "load_reference_barrier_strong_narrow";
984 } else {
985 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong);
986 name = "load_reference_barrier_strong";
987 }
988 } else if (is_weak) {
989 if (is_narrow) {
990 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak_narrow);
991 name = "load_reference_barrier_weak_narrow";
992 } else {
993 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak);
994 name = "load_reference_barrier_weak";
995 }
996 } else {
997 assert(is_phantom, "only remaining strength");
998 if (is_narrow) {
999 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom_narrow);
1000 name = "load_reference_barrier_phantom_narrow";
1001 } else {
1002 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom);
1003 name = "load_reference_barrier_phantom";
1004 }
1005 }
1006 Node* call = new CallLeafNode(ShenandoahBarrierSetC2::shenandoah_load_reference_barrier_Type(), calladdr, name, TypeRawPtr::BOTTOM);
1007
1008 call->init_req(TypeFunc::Control, ctrl);
1009 call->init_req(TypeFunc::I_O, phase->C->top());
1010 call->init_req(TypeFunc::Memory, phase->C->top());
1011 call->init_req(TypeFunc::FramePtr, phase->C->top());
1012 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
1013 call->init_req(TypeFunc::Parms, val);
1014 call->init_req(TypeFunc::Parms+1, load_addr);
1015 phase->register_control(call, loop, ctrl);
1016 ctrl = new ProjNode(call, TypeFunc::Control);
1017 phase->register_control(ctrl, loop, call);
1018 val = new ProjNode(call, TypeFunc::Parms);
1019 phase->register_new_node(val, call);
1020 val = new CheckCastPPNode(ctrl, val, obj_type);
1021 phase->register_new_node(val, ctrl);
1022 }
1023
1024 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) {
1025 Node* ctrl = phase->get_ctrl(barrier);
1026 Node* init_raw_mem = fixer.find_mem(ctrl, barrier);
1027
1028 // Update the control of all nodes that should be after the
1029 // barrier control flow
1030 uses.clear();
1031 // Every node that is control dependent on the barrier's input
1032 // control will be after the expanded barrier. The raw memory (if
1033 // its memory is control dependent on the barrier's input control)
1034 // must stay above the barrier.
1035 uses_to_ignore.clear();
1036 if (phase->has_ctrl(init_raw_mem) && phase->get_ctrl(init_raw_mem) == ctrl && !init_raw_mem->is_Phi()) {
1037 uses_to_ignore.push(init_raw_mem);
1038 }
1039 for (uint next = 0; next < uses_to_ignore.size(); next++) {
1040 Node *n = uses_to_ignore.at(next);
1041 for (uint i = 0; i < n->req(); i++) {
1042 Node* in = n->in(i);
1043 if (in != nullptr && phase->has_ctrl(in) && phase->get_ctrl(in) == ctrl) {
1044 uses_to_ignore.push(in);
1045 }
1046 }
1047 }
1048 for (DUIterator_Fast imax, i = ctrl->fast_outs(imax); i < imax; i++) {
1049 Node* u = ctrl->fast_out(i);
1050 if (u->_idx < last &&
1051 u != barrier &&
1052 !uses_to_ignore.member(u) &&
1053 (u->in(0) != ctrl || (!u->is_Region() && !u->is_Phi())) &&
1054 (ctrl->Opcode() != Op_CatchProj || u->Opcode() != Op_CreateEx)) {
1055 Node* old_c = phase->ctrl_or_self(u);
1056 Node* c = old_c;
1057 if (c != ctrl ||
1058 is_dominator_same_ctrl(old_c, barrier, u, phase) ||
1059 ShenandoahBarrierSetC2::is_shenandoah_state_load(u)) {
1060 phase->igvn().rehash_node_delayed(u);
1061 int nb = u->replace_edge(ctrl, region, &phase->igvn());
1062 if (u->is_CFG()) {
1063 if (phase->idom(u) == ctrl) {
1064 phase->set_idom(u, region, phase->dom_depth(region));
1065 }
1066 } else if (phase->get_ctrl(u) == ctrl) {
1067 assert(u != init_raw_mem, "should leave input raw mem above the barrier");
1068 uses.push(u);
1069 }
1070 assert(nb == 1, "more than 1 ctrl input?");
1071 --i, imax -= nb;
1072 }
1073 }
1074 }
1075 }
1076
1077 static Node* create_phis_on_call_return(Node* ctrl, Node* c, Node* n, Node* n_clone, const CallProjections* projs, PhaseIdealLoop* phase) {
1078 Node* region = nullptr;
1079 while (c != ctrl) {
1080 if (c->is_Region()) {
1081 region = c;
1082 }
1083 c = phase->idom(c);
1084 }
1085 assert(region != nullptr, "");
1086 Node* phi = new PhiNode(region, n->bottom_type());
1087 for (uint j = 1; j < region->req(); j++) {
1088 Node* in = region->in(j);
1089 if (phase->is_dominator(projs->fallthrough_catchproj, in)) {
1090 phi->init_req(j, n);
1091 } else if (phase->is_dominator(projs->catchall_catchproj, in)) {
1092 phi->init_req(j, n_clone);
1093 } else {
1094 phi->init_req(j, create_phis_on_call_return(ctrl, in, n, n_clone, projs, phase));
1095 }
1096 }
1097 phase->register_new_node(phi, region);
1098 return phi;
1099 }
1100
1101 void ShenandoahBarrierC2Support::pin_and_expand(PhaseIdealLoop* phase) {
1102 ShenandoahBarrierSetC2State* state = ShenandoahBarrierSetC2::bsc2()->state();
1103
1104 Unique_Node_List uses;
1105 for (int i = 0; i < state->iu_barriers_count(); i++) {
1106 Node* barrier = state->iu_barrier(i);
1107 Node* ctrl = phase->get_ctrl(barrier);
1108 IdealLoopTree* loop = phase->get_loop(ctrl);
1109 Node* head = loop->head();
1110 if (head->is_OuterStripMinedLoop()) {
1111 // Expanding a barrier here will break loop strip mining
1112 // verification. Transform the loop so the loop nest doesn't
1113 // appear as strip mined.
1114 OuterStripMinedLoopNode* outer = head->as_OuterStripMinedLoop();
1115 hide_strip_mined_loop(outer, outer->unique_ctrl_out()->as_CountedLoop(), phase);
1116 }
1117 }
1118
1119 Node_Stack stack(0);
1120 Node_List clones;
1121 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1122 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1123
1124 Node* ctrl = phase->get_ctrl(lrb);
1125 Node* val = lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
1126
1127 CallStaticJavaNode* unc = nullptr;
1128 Node* unc_ctrl = nullptr;
1129 Node* uncasted_val = val;
1130
1131 for (DUIterator_Fast imax, i = lrb->fast_outs(imax); i < imax; i++) {
1132 Node* u = lrb->fast_out(i);
1133 if (u->Opcode() == Op_CastPP &&
1134 u->in(0) != nullptr &&
1135 phase->is_dominator(u->in(0), ctrl)) {
1136 const Type* u_t = phase->igvn().type(u);
1137
1138 if (u_t->meet(TypePtr::NULL_PTR) != u_t &&
1139 u->in(0)->Opcode() == Op_IfTrue &&
1140 u->in(0)->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) &&
1141 u->in(0)->in(0)->is_If() &&
1142 u->in(0)->in(0)->in(1)->Opcode() == Op_Bool &&
1143 u->in(0)->in(0)->in(1)->as_Bool()->_test._test == BoolTest::ne &&
1144 u->in(0)->in(0)->in(1)->in(1)->Opcode() == Op_CmpP &&
1145 u->in(0)->in(0)->in(1)->in(1)->in(1) == val &&
1146 u->in(0)->in(0)->in(1)->in(1)->in(2)->bottom_type() == TypePtr::NULL_PTR) {
1147 IdealLoopTree* loop = phase->get_loop(ctrl);
1148 IdealLoopTree* unc_loop = phase->get_loop(u->in(0));
1149
1150 if (!unc_loop->is_member(loop)) {
1151 continue;
1152 }
1153
1154 Node* branch = no_branches(ctrl, u->in(0), false, phase);
1155 assert(branch == nullptr || branch == NodeSentinel, "was not looking for a branch");
1156 if (branch == NodeSentinel) {
1157 continue;
1158 }
1159
1160 Node* iff = u->in(0)->in(0);
1161 Node* bol = iff->in(1)->clone();
1162 Node* cmp = bol->in(1)->clone();
1163 cmp->set_req(1, lrb);
1164 bol->set_req(1, cmp);
1165 phase->igvn().replace_input_of(iff, 1, bol);
1166 phase->set_ctrl(lrb, iff->in(0));
1167 phase->register_new_node(cmp, iff->in(0));
1168 phase->register_new_node(bol, iff->in(0));
1169 break;
1170 }
1171 }
1172 }
1173 if ((ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) || ctrl->is_CallJava()) {
1174 CallNode* call = ctrl->is_Proj() ? ctrl->in(0)->as_CallJava() : ctrl->as_CallJava();
1175 if (call->entry_point() == OptoRuntime::rethrow_stub()) {
1176 // The rethrow call may have too many projections to be
1177 // properly handled here. Given there's no reason for a
1178 // barrier to depend on the call, move it above the call
1179 stack.push(lrb, 0);
1180 do {
1181 Node* n = stack.node();
1182 uint idx = stack.index();
1183 if (idx < n->req()) {
1184 Node* in = n->in(idx);
1185 stack.set_index(idx+1);
1186 if (in != nullptr) {
1187 if (phase->has_ctrl(in)) {
1188 if (phase->is_dominator(call, phase->get_ctrl(in))) {
1189 #ifdef ASSERT
1190 for (uint i = 0; i < stack.size(); i++) {
1191 assert(stack.node_at(i) != in, "node shouldn't have been seen yet");
1192 }
1193 #endif
1194 stack.push(in, 0);
1195 }
1196 } else {
1197 assert(phase->is_dominator(in, call->in(0)), "no dependency on the call");
1198 }
1199 }
1200 } else {
1201 phase->set_ctrl(n, call->in(0));
1202 stack.pop();
1203 }
1204 } while(stack.size() > 0);
1205 continue;
1206 }
1207 CallProjections* projs = call->extract_projections(false, false);
1208 #ifdef ASSERT
1209 VectorSet cloned;
1210 #endif
1211 Node* lrb_clone = lrb->clone();
1212 phase->register_new_node(lrb_clone, projs->catchall_catchproj);
1213 phase->set_ctrl(lrb, projs->fallthrough_catchproj);
1214
1215 stack.push(lrb, 0);
1216 clones.push(lrb_clone);
1217
1218 do {
1219 assert(stack.size() == clones.size(), "");
1220 Node* n = stack.node();
1221 #ifdef ASSERT
1222 if (n->is_Load()) {
1223 Node* mem = n->in(MemNode::Memory);
1224 for (DUIterator_Fast jmax, j = mem->fast_outs(jmax); j < jmax; j++) {
1225 Node* u = mem->fast_out(j);
1226 assert(!u->is_Store() || !u->is_LoadStore() || phase->get_ctrl(u) != ctrl, "anti dependent store?");
1227 }
1228 }
1229 #endif
1230 uint idx = stack.index();
1231 Node* n_clone = clones.at(clones.size()-1);
1232 if (idx < n->outcnt()) {
1233 Node* u = n->raw_out(idx);
1234 Node* c = phase->ctrl_or_self(u);
1235 if (phase->is_dominator(call, c) && phase->is_dominator(c, projs->fallthrough_proj)) {
1236 stack.set_index(idx+1);
1237 assert(!u->is_CFG(), "");
1238 stack.push(u, 0);
1239 assert(!cloned.test_set(u->_idx), "only one clone");
1240 Node* u_clone = u->clone();
1241 int nb = u_clone->replace_edge(n, n_clone, &phase->igvn());
1242 assert(nb > 0, "should have replaced some uses");
1243 phase->register_new_node(u_clone, projs->catchall_catchproj);
1244 clones.push(u_clone);
1245 phase->set_ctrl(u, projs->fallthrough_catchproj);
1246 } else {
1247 bool replaced = false;
1248 if (u->is_Phi()) {
1249 for (uint k = 1; k < u->req(); k++) {
1250 if (u->in(k) == n) {
1251 if (phase->is_dominator(projs->catchall_catchproj, u->in(0)->in(k))) {
1252 phase->igvn().replace_input_of(u, k, n_clone);
1253 replaced = true;
1254 } else if (!phase->is_dominator(projs->fallthrough_catchproj, u->in(0)->in(k))) {
1255 phase->igvn().replace_input_of(u, k, create_phis_on_call_return(ctrl, u->in(0)->in(k), n, n_clone, projs, phase));
1256 replaced = true;
1257 }
1258 }
1259 }
1260 } else {
1261 if (phase->is_dominator(projs->catchall_catchproj, c)) {
1262 phase->igvn().rehash_node_delayed(u);
1263 int nb = u->replace_edge(n, n_clone, &phase->igvn());
1264 assert(nb > 0, "should have replaced some uses");
1265 replaced = true;
1266 } else if (!phase->is_dominator(projs->fallthrough_catchproj, c)) {
1267 if (u->is_If()) {
1268 // Can't break If/Bool/Cmp chain
1269 assert(n->is_Bool(), "unexpected If shape");
1270 assert(stack.node_at(stack.size()-2)->is_Cmp(), "unexpected If shape");
1271 assert(n_clone->is_Bool(), "unexpected clone");
1272 assert(clones.at(clones.size()-2)->is_Cmp(), "unexpected clone");
1273 Node* bol_clone = n->clone();
1274 Node* cmp_clone = stack.node_at(stack.size()-2)->clone();
1275 bol_clone->set_req(1, cmp_clone);
1276
1277 Node* nn = stack.node_at(stack.size()-3);
1278 Node* nn_clone = clones.at(clones.size()-3);
1279 assert(nn->Opcode() == nn_clone->Opcode(), "mismatch");
1280
1281 int nb = cmp_clone->replace_edge(nn, create_phis_on_call_return(ctrl, c, nn, nn_clone, projs, phase),
1282 &phase->igvn());
1283 assert(nb > 0, "should have replaced some uses");
1284
1285 phase->register_new_node(bol_clone, u->in(0));
1286 phase->register_new_node(cmp_clone, u->in(0));
1287
1288 phase->igvn().replace_input_of(u, 1, bol_clone);
1289
1290 } else {
1291 phase->igvn().rehash_node_delayed(u);
1292 int nb = u->replace_edge(n, create_phis_on_call_return(ctrl, c, n, n_clone, projs, phase), &phase->igvn());
1293 assert(nb > 0, "should have replaced some uses");
1294 }
1295 replaced = true;
1296 }
1297 }
1298 if (!replaced) {
1299 stack.set_index(idx+1);
1300 }
1301 }
1302 } else {
1303 stack.pop();
1304 clones.pop();
1305 }
1306 } while (stack.size() > 0);
1307 assert(stack.size() == 0 && clones.size() == 0, "");
1308 }
1309 }
1310
1311 for (int i = 0; i < state->load_reference_barriers_count(); i++) {
1312 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1313 Node* ctrl = phase->get_ctrl(lrb);
1314 IdealLoopTree* loop = phase->get_loop(ctrl);
1315 Node* head = loop->head();
1316 if (head->is_OuterStripMinedLoop()) {
1317 // Expanding a barrier here will break loop strip mining
1318 // verification. Transform the loop so the loop nest doesn't
1319 // appear as strip mined.
1320 OuterStripMinedLoopNode* outer = head->as_OuterStripMinedLoop();
1321 hide_strip_mined_loop(outer, outer->unique_ctrl_out()->as_CountedLoop(), phase);
1322 }
1323 }
1324
1325 // Expand load-reference-barriers
1326 MemoryGraphFixer fixer(Compile::AliasIdxRaw, true, phase);
1327 Unique_Node_List uses_to_ignore;
1328 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1329 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1330 uint last = phase->C->unique();
1331 Node* ctrl = phase->get_ctrl(lrb);
1332 Node* val = lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
1333
1334 Node* orig_ctrl = ctrl;
1335
1336 Node* raw_mem = fixer.find_mem(ctrl, lrb);
1337 Node* raw_mem_for_ctrl = fixer.find_mem(ctrl, nullptr);
1338
1339 IdealLoopTree *loop = phase->get_loop(ctrl);
1340
1341 Node* heap_stable_ctrl = nullptr;
1342 Node* null_ctrl = nullptr;
1343
1344 assert(val->bottom_type()->make_oopptr(), "need oop");
1345 assert(val->bottom_type()->make_oopptr()->const_oop() == nullptr, "expect non-constant");
1346
1347 enum { _heap_stable = 1, _evac_path, _not_cset, PATH_LIMIT };
1348 Node* region = new RegionNode(PATH_LIMIT);
1349 Node* val_phi = new PhiNode(region, val->bottom_type()->is_oopptr());
1350
1351 // Stable path.
1352 int flags = ShenandoahHeap::HAS_FORWARDED;
1353 if (!ShenandoahBarrierSet::is_strong_access(lrb->decorators())) {
1354 flags |= ShenandoahHeap::WEAK_ROOTS;
1355 }
1356 test_gc_state(ctrl, raw_mem, heap_stable_ctrl, phase, flags);
1357 IfNode* heap_stable_iff = heap_stable_ctrl->in(0)->as_If();
1358
1359 // Heap stable case
1360 region->init_req(_heap_stable, heap_stable_ctrl);
1361 val_phi->init_req(_heap_stable, val);
1362
1363 // Test for in-cset, unless it's a native-LRB. Native LRBs need to return null
1364 // even for non-cset objects to prevent resurrection of such objects.
1365 // Wires !in_cset(obj) to slot 2 of region and phis
1366 Node* not_cset_ctrl = nullptr;
1367 if (ShenandoahBarrierSet::is_strong_access(lrb->decorators())) {
1368 test_in_cset(ctrl, not_cset_ctrl, val, raw_mem, phase);
1369 }
1370 if (not_cset_ctrl != nullptr) {
1371 region->init_req(_not_cset, not_cset_ctrl);
1372 val_phi->init_req(_not_cset, val);
1373 } else {
1374 region->del_req(_not_cset);
1375 val_phi->del_req(_not_cset);
1376 }
1377
1378 // Resolve object when orig-value is in cset.
1379 // Make the unconditional resolve for fwdptr.
1380
1381 // Call lrb-stub and wire up that path in slots 4
1382 Node* result_mem = nullptr;
1383
1384 Node* addr;
1385 if (ShenandoahSelfFixing) {
1386 VectorSet visited;
1387 addr = get_load_addr(phase, visited, lrb);
1388 } else {
1389 addr = phase->igvn().zerocon(T_OBJECT);
1390 }
1391 if (addr->Opcode() == Op_AddP) {
1392 Node* orig_base = addr->in(AddPNode::Base);
1393 Node* base = new CheckCastPPNode(ctrl, orig_base, orig_base->bottom_type(), ConstraintCastNode::StrongDependency);
1394 phase->register_new_node(base, ctrl);
1395 if (addr->in(AddPNode::Base) == addr->in((AddPNode::Address))) {
1396 // Field access
1397 addr = addr->clone();
1398 addr->set_req(AddPNode::Base, base);
1399 addr->set_req(AddPNode::Address, base);
1400 phase->register_new_node(addr, ctrl);
1401 } else {
1402 Node* addr2 = addr->in(AddPNode::Address);
1403 if (addr2->Opcode() == Op_AddP && addr2->in(AddPNode::Base) == addr2->in(AddPNode::Address) &&
1404 addr2->in(AddPNode::Base) == orig_base) {
1405 addr2 = addr2->clone();
1406 addr2->set_req(AddPNode::Base, base);
1407 addr2->set_req(AddPNode::Address, base);
1408 phase->register_new_node(addr2, ctrl);
1409 addr = addr->clone();
1410 addr->set_req(AddPNode::Base, base);
1411 addr->set_req(AddPNode::Address, addr2);
1412 phase->register_new_node(addr, ctrl);
1413 }
1414 }
1415 }
1416 call_lrb_stub(ctrl, val, addr, lrb->decorators(), phase);
1417 region->init_req(_evac_path, ctrl);
1418 val_phi->init_req(_evac_path, val);
1419
1420 phase->register_control(region, loop, heap_stable_iff);
1421 Node* out_val = val_phi;
1422 phase->register_new_node(val_phi, region);
1423
1424 fix_ctrl(lrb, region, fixer, uses, uses_to_ignore, last, phase);
1425
1426 ctrl = orig_ctrl;
1427
1428 phase->igvn().replace_node(lrb, out_val);
1429
1430 follow_barrier_uses(out_val, ctrl, uses, phase);
1431
1432 for(uint next = 0; next < uses.size(); next++ ) {
1433 Node *n = uses.at(next);
1434 assert(phase->get_ctrl(n) == ctrl, "bad control");
1435 assert(n != raw_mem, "should leave input raw mem above the barrier");
1436 phase->set_ctrl(n, region);
1437 follow_barrier_uses(n, ctrl, uses, phase);
1438 }
1439 fixer.record_new_ctrl(ctrl, region, raw_mem, raw_mem_for_ctrl);
1440 }
1441 // Done expanding load-reference-barriers.
1442 assert(ShenandoahBarrierSetC2::bsc2()->state()->load_reference_barriers_count() == 0, "all load reference barrier nodes should have been replaced");
1443
1444 for (int i = state->iu_barriers_count() - 1; i >= 0; i--) {
1445 Node* barrier = state->iu_barrier(i);
1446 Node* pre_val = barrier->in(1);
1447
1448 if (phase->igvn().type(pre_val)->higher_equal(TypePtr::NULL_PTR)) {
1449 ShouldNotReachHere();
1450 continue;
1451 }
1452
1453 Node* ctrl = phase->get_ctrl(barrier);
1454
1455 if (ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) {
1456 assert(is_dominator(phase->get_ctrl(pre_val), ctrl->in(0)->in(0), pre_val, ctrl->in(0), phase), "can't move");
1457 ctrl = ctrl->in(0)->in(0);
1458 phase->set_ctrl(barrier, ctrl);
1459 } else if (ctrl->is_CallRuntime()) {
1460 assert(is_dominator(phase->get_ctrl(pre_val), ctrl->in(0), pre_val, ctrl, phase), "can't move");
1461 ctrl = ctrl->in(0);
1462 phase->set_ctrl(barrier, ctrl);
1463 }
1464
1465 Node* init_ctrl = ctrl;
1466 IdealLoopTree* loop = phase->get_loop(ctrl);
1467 Node* raw_mem = fixer.find_mem(ctrl, barrier);
1468 Node* init_raw_mem = raw_mem;
1469 Node* raw_mem_for_ctrl = fixer.find_mem(ctrl, nullptr);
1470 Node* heap_stable_ctrl = nullptr;
1471 Node* null_ctrl = nullptr;
1472 uint last = phase->C->unique();
1473
1474 enum { _heap_stable = 1, _heap_unstable, PATH_LIMIT };
1475 Node* region = new RegionNode(PATH_LIMIT);
1476 Node* phi = PhiNode::make(region, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
1477
1478 enum { _fast_path = 1, _slow_path, _null_path, PATH_LIMIT2 };
1479 Node* region2 = new RegionNode(PATH_LIMIT2);
1480 Node* phi2 = PhiNode::make(region2, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
1481
1482 // Stable path.
1483 test_gc_state(ctrl, raw_mem, heap_stable_ctrl, phase, ShenandoahHeap::MARKING);
1484 region->init_req(_heap_stable, heap_stable_ctrl);
1485 phi->init_req(_heap_stable, raw_mem);
1486
1487 // Null path
1488 Node* reg2_ctrl = nullptr;
1489 test_null(ctrl, pre_val, null_ctrl, phase);
1490 if (null_ctrl != nullptr) {
1491 reg2_ctrl = null_ctrl->in(0);
1492 region2->init_req(_null_path, null_ctrl);
1493 phi2->init_req(_null_path, raw_mem);
1494 } else {
1495 region2->del_req(_null_path);
1496 phi2->del_req(_null_path);
1497 }
1498
1499 const int index_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset());
1500 const int buffer_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset());
1501 Node* thread = new ThreadLocalNode();
1502 phase->register_new_node(thread, ctrl);
1503 Node* buffer_adr = new AddPNode(phase->C->top(), thread, phase->igvn().MakeConX(buffer_offset));
1504 phase->register_new_node(buffer_adr, ctrl);
1505 Node* index_adr = new AddPNode(phase->C->top(), thread, phase->igvn().MakeConX(index_offset));
1506 phase->register_new_node(index_adr, ctrl);
1507
1508 BasicType index_bt = TypeX_X->basic_type();
1509 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading Shenandoah SATBMarkQueue::_index with wrong size.");
1510 const TypePtr* adr_type = TypeRawPtr::BOTTOM;
1511 Node* index = new LoadXNode(ctrl, raw_mem, index_adr, adr_type, TypeX_X, MemNode::unordered);
1512 phase->register_new_node(index, ctrl);
1513 Node* index_cmp = new CmpXNode(index, phase->igvn().MakeConX(0));
1514 phase->register_new_node(index_cmp, ctrl);
1515 Node* index_test = new BoolNode(index_cmp, BoolTest::ne);
1516 phase->register_new_node(index_test, ctrl);
1517 IfNode* queue_full_iff = new IfNode(ctrl, index_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
1518 if (reg2_ctrl == nullptr) reg2_ctrl = queue_full_iff;
1519 phase->register_control(queue_full_iff, loop, ctrl);
1520 Node* not_full = new IfTrueNode(queue_full_iff);
1521 phase->register_control(not_full, loop, queue_full_iff);
1522 Node* full = new IfFalseNode(queue_full_iff);
1523 phase->register_control(full, loop, queue_full_iff);
1524
1525 ctrl = not_full;
1526
1527 Node* next_index = new SubXNode(index, phase->igvn().MakeConX(sizeof(intptr_t)));
1528 phase->register_new_node(next_index, ctrl);
1529
1530 Node* buffer = new LoadPNode(ctrl, raw_mem, buffer_adr, adr_type, TypeRawPtr::NOTNULL, MemNode::unordered);
1531 phase->register_new_node(buffer, ctrl);
1532 Node *log_addr = new AddPNode(phase->C->top(), buffer, next_index);
1533 phase->register_new_node(log_addr, ctrl);
1534 Node* log_store = new StorePNode(ctrl, raw_mem, log_addr, adr_type, pre_val, MemNode::unordered);
1535 phase->register_new_node(log_store, ctrl);
1536 // update the index
1537 Node* index_update = new StoreXNode(ctrl, log_store, index_adr, adr_type, next_index, MemNode::unordered);
1538 phase->register_new_node(index_update, ctrl);
1539
1540 // Fast-path case
1541 region2->init_req(_fast_path, ctrl);
1542 phi2->init_req(_fast_path, index_update);
1543
1544 ctrl = full;
1545
1546 Node* base = find_bottom_mem(ctrl, phase);
1547
1548 MergeMemNode* mm = MergeMemNode::make(base);
1549 mm->set_memory_at(Compile::AliasIdxRaw, raw_mem);
1550 phase->register_new_node(mm, ctrl);
1551
1552 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);
1553 call->init_req(TypeFunc::Control, ctrl);
1554 call->init_req(TypeFunc::I_O, phase->C->top());
1555 call->init_req(TypeFunc::Memory, mm);
1556 call->init_req(TypeFunc::FramePtr, phase->C->top());
1557 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
1558 call->init_req(TypeFunc::Parms, pre_val);
1559 call->init_req(TypeFunc::Parms+1, thread);
1560 phase->register_control(call, loop, ctrl);
1561
1562 Node* ctrl_proj = new ProjNode(call, TypeFunc::Control);
1563 phase->register_control(ctrl_proj, loop, call);
1564 Node* mem_proj = new ProjNode(call, TypeFunc::Memory);
1565 phase->register_new_node(mem_proj, call);
1566
1567 // Slow-path case
1568 region2->init_req(_slow_path, ctrl_proj);
1569 phi2->init_req(_slow_path, mem_proj);
1570
1571 phase->register_control(region2, loop, reg2_ctrl);
1572 phase->register_new_node(phi2, region2);
1573
1574 region->init_req(_heap_unstable, region2);
1575 phi->init_req(_heap_unstable, phi2);
1576
1577 phase->register_control(region, loop, heap_stable_ctrl->in(0));
1578 phase->register_new_node(phi, region);
1579
1580 fix_ctrl(barrier, region, fixer, uses, uses_to_ignore, last, phase);
1581 for(uint next = 0; next < uses.size(); next++ ) {
1582 Node *n = uses.at(next);
1583 assert(phase->get_ctrl(n) == init_ctrl, "bad control");
1584 assert(n != init_raw_mem, "should leave input raw mem above the barrier");
1585 phase->set_ctrl(n, region);
1586 follow_barrier_uses(n, init_ctrl, uses, phase);
1587 }
1588 fixer.fix_mem(init_ctrl, region, init_raw_mem, raw_mem_for_ctrl, phi, uses);
1589
1590 phase->igvn().replace_node(barrier, pre_val);
1591 }
1592 assert(state->iu_barriers_count() == 0, "all enqueue barrier nodes should have been replaced");
1593
1594 }
1595
1596 Node* ShenandoahBarrierC2Support::get_load_addr(PhaseIdealLoop* phase, VectorSet& visited, Node* in) {
1597 if (visited.test_set(in->_idx)) {
1598 return nullptr;
1599 }
1600 switch (in->Opcode()) {
1601 case Op_Proj:
1602 return get_load_addr(phase, visited, in->in(0));
1603 case Op_CastPP:
1604 case Op_CheckCastPP:
1605 case Op_DecodeN:
1606 case Op_EncodeP:
1607 return get_load_addr(phase, visited, in->in(1));
1608 case Op_LoadN:
1609 case Op_LoadP:
1610 return in->in(MemNode::Address);
1611 case Op_CompareAndExchangeN:
1612 case Op_CompareAndExchangeP:
1613 case Op_GetAndSetN:
1614 case Op_GetAndSetP:
1615 case Op_ShenandoahCompareAndExchangeP:
1616 case Op_ShenandoahCompareAndExchangeN:
1617 // Those instructions would just have stored a different
1618 // value into the field. No use to attempt to fix it at this point.
1619 return phase->igvn().zerocon(T_OBJECT);
1620 case Op_CMoveP:
1621 case Op_CMoveN: {
1622 Node* t = get_load_addr(phase, visited, in->in(CMoveNode::IfTrue));
1623 Node* f = get_load_addr(phase, visited, in->in(CMoveNode::IfFalse));
1624 // Handle unambiguous cases: single address reported on both branches.
1625 if (t != nullptr && f == nullptr) return t;
1626 if (t == nullptr && f != nullptr) return f;
1627 if (t != nullptr && t == f) return t;
1628 // Ambiguity.
1629 return phase->igvn().zerocon(T_OBJECT);
1630 }
1631 case Op_Phi: {
1632 Node* addr = nullptr;
1633 for (uint i = 1; i < in->req(); i++) {
1634 Node* addr1 = get_load_addr(phase, visited, in->in(i));
1635 if (addr == nullptr) {
1636 addr = addr1;
1637 }
1638 if (addr != addr1) {
1639 return phase->igvn().zerocon(T_OBJECT);
1640 }
1641 }
1642 return addr;
1643 }
1644 case Op_ShenandoahLoadReferenceBarrier:
1645 return get_load_addr(phase, visited, in->in(ShenandoahLoadReferenceBarrierNode::ValueIn));
1646 case Op_ShenandoahIUBarrier:
1647 return get_load_addr(phase, visited, in->in(1));
1648 case Op_CallDynamicJava:
1649 case Op_CallLeaf:
1650 case Op_CallStaticJava:
1651 case Op_ConN:
1652 case Op_ConP:
1653 case Op_Parm:
1654 case Op_CreateEx:
1655 return phase->igvn().zerocon(T_OBJECT);
1656 default:
1657 #ifdef ASSERT
1658 fatal("Unknown node in get_load_addr: %s", NodeClassNames[in->Opcode()]);
1659 #endif
1660 return phase->igvn().zerocon(T_OBJECT);
1661 }
1662
1663 }
1664
1665 void ShenandoahBarrierC2Support::move_gc_state_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase) {
1666 IdealLoopTree *loop = phase->get_loop(iff);
1667 Node* loop_head = loop->_head;
1668 Node* entry_c = loop_head->in(LoopNode::EntryControl);
1669
1670 Node* bol = iff->in(1);
1671 Node* cmp = bol->in(1);
1672 Node* andi = cmp->in(1);
1673 Node* load = andi->in(1);
1674
1675 assert(is_gc_state_load(load), "broken");
1676 if (!phase->is_dominator(load->in(0), entry_c)) {
1677 Node* mem_ctrl = nullptr;
1678 Node* mem = dom_mem(load->in(MemNode::Memory), loop_head, Compile::AliasIdxRaw, mem_ctrl, phase);
1679 load = load->clone();
1680 load->set_req(MemNode::Memory, mem);
1681 load->set_req(0, entry_c);
1682 phase->register_new_node(load, entry_c);
1683 andi = andi->clone();
1684 andi->set_req(1, load);
1685 phase->register_new_node(andi, entry_c);
1686 cmp = cmp->clone();
1687 cmp->set_req(1, andi);
1688 phase->register_new_node(cmp, entry_c);
1689 bol = bol->clone();
1690 bol->set_req(1, cmp);
1691 phase->register_new_node(bol, entry_c);
1692
1693 phase->igvn().replace_input_of(iff, 1, bol);
1694 }
1695 }
1696
1697 bool ShenandoahBarrierC2Support::identical_backtoback_ifs(Node* n, PhaseIdealLoop* phase) {
1698 if (!n->is_If() || n->is_CountedLoopEnd()) {
1699 return false;
1700 }
1701 Node* region = n->in(0);
1702
1703 if (!region->is_Region()) {
1704 return false;
1705 }
1706 Node* dom = phase->idom(region);
1707 if (!dom->is_If()) {
1708 return false;
1709 }
1710
1711 if (!is_heap_stable_test(n) || !is_heap_stable_test(dom)) {
1712 return false;
1713 }
1714
1715 IfNode* dom_if = dom->as_If();
1716 Node* proj_true = dom_if->proj_out(1);
1717 Node* proj_false = dom_if->proj_out(0);
1718
1719 for (uint i = 1; i < region->req(); i++) {
1720 if (phase->is_dominator(proj_true, region->in(i))) {
1721 continue;
1722 }
1723 if (phase->is_dominator(proj_false, region->in(i))) {
1724 continue;
1725 }
1726 return false;
1727 }
1728
1729 return true;
1730 }
1731
1732 void ShenandoahBarrierC2Support::merge_back_to_back_tests(Node* n, PhaseIdealLoop* phase) {
1733 assert(is_heap_stable_test(n), "no other tests");
1734 if (identical_backtoback_ifs(n, phase)) {
1735 Node* n_ctrl = n->in(0);
1736 if (phase->can_split_if(n_ctrl)) {
1737 IfNode* dom_if = phase->idom(n_ctrl)->as_If();
1738 if (is_heap_stable_test(n)) {
1739 Node* gc_state_load = n->in(1)->in(1)->in(1)->in(1);
1740 assert(is_gc_state_load(gc_state_load), "broken");
1741 Node* dom_gc_state_load = dom_if->in(1)->in(1)->in(1)->in(1);
1742 assert(is_gc_state_load(dom_gc_state_load), "broken");
1743 if (gc_state_load != dom_gc_state_load) {
1744 phase->igvn().replace_node(gc_state_load, dom_gc_state_load);
1745 }
1746 }
1747 PhiNode* bolphi = PhiNode::make_blank(n_ctrl, n->in(1));
1748 Node* proj_true = dom_if->proj_out(1);
1749 Node* proj_false = dom_if->proj_out(0);
1750 Node* con_true = phase->igvn().makecon(TypeInt::ONE);
1751 Node* con_false = phase->igvn().makecon(TypeInt::ZERO);
1752
1753 for (uint i = 1; i < n_ctrl->req(); i++) {
1754 if (phase->is_dominator(proj_true, n_ctrl->in(i))) {
1755 bolphi->init_req(i, con_true);
1756 } else {
1757 assert(phase->is_dominator(proj_false, n_ctrl->in(i)), "bad if");
1758 bolphi->init_req(i, con_false);
1759 }
1760 }
1761 phase->register_new_node(bolphi, n_ctrl);
1762 phase->igvn().replace_input_of(n, 1, bolphi);
1763 phase->do_split_if(n);
1764 }
1765 }
1766 }
1767
1768 IfNode* ShenandoahBarrierC2Support::find_unswitching_candidate(const IdealLoopTree* loop, PhaseIdealLoop* phase) {
1769 // Find first invariant test that doesn't exit the loop
1770 LoopNode *head = loop->_head->as_Loop();
1771 IfNode* unswitch_iff = nullptr;
1772 Node* n = head->in(LoopNode::LoopBackControl);
1773 int loop_has_sfpts = -1;
1774 while (n != head) {
1775 Node* n_dom = phase->idom(n);
1776 if (n->is_Region()) {
1777 if (n_dom->is_If()) {
1778 IfNode* iff = n_dom->as_If();
1779 if (iff->in(1)->is_Bool()) {
1780 BoolNode* bol = iff->in(1)->as_Bool();
1781 if (bol->in(1)->is_Cmp()) {
1782 // If condition is invariant and not a loop exit,
1783 // then found reason to unswitch.
1784 if (is_heap_stable_test(iff) &&
1785 (loop_has_sfpts == -1 || loop_has_sfpts == 0)) {
1786 assert(!loop->is_loop_exit(iff), "both branches should be in the loop");
1787 if (loop_has_sfpts == -1) {
1788 for(uint i = 0; i < loop->_body.size(); i++) {
1789 Node *m = loop->_body[i];
1790 if (m->is_SafePoint() && !m->is_CallLeaf()) {
1791 loop_has_sfpts = 1;
1792 break;
1793 }
1794 }
1795 if (loop_has_sfpts == -1) {
1796 loop_has_sfpts = 0;
1797 }
1798 }
1799 if (!loop_has_sfpts) {
1800 unswitch_iff = iff;
1801 }
1802 }
1803 }
1804 }
1805 }
1806 }
1807 n = n_dom;
1808 }
1809 return unswitch_iff;
1810 }
1811
1812
1813 void ShenandoahBarrierC2Support::optimize_after_expansion(VectorSet &visited, Node_Stack &stack, Node_List &old_new, PhaseIdealLoop* phase) {
1814 Node_List heap_stable_tests;
1815 stack.push(phase->C->start(), 0);
1816 do {
1817 Node* n = stack.node();
1818 uint i = stack.index();
1819
1820 if (i < n->outcnt()) {
1821 Node* u = n->raw_out(i);
1822 stack.set_index(i+1);
1823 if (!visited.test_set(u->_idx)) {
1824 stack.push(u, 0);
1825 }
1826 } else {
1827 stack.pop();
1828 if (n->is_If() && is_heap_stable_test(n)) {
1829 heap_stable_tests.push(n);
1830 }
1831 }
1832 } while (stack.size() > 0);
1833
1834 for (uint i = 0; i < heap_stable_tests.size(); i++) {
1835 Node* n = heap_stable_tests.at(i);
1836 assert(is_heap_stable_test(n), "only evacuation test");
1837 merge_back_to_back_tests(n, phase);
1838 }
1839
1840 if (!phase->C->major_progress()) {
1841 VectorSet seen;
1842 for (uint i = 0; i < heap_stable_tests.size(); i++) {
1843 Node* n = heap_stable_tests.at(i);
1844 IdealLoopTree* loop = phase->get_loop(n);
1845 if (loop != phase->ltree_root() &&
1846 loop->_child == nullptr &&
1847 !loop->_irreducible) {
1848 Node* head = loop->_head;
1849 if (head->is_Loop() &&
1850 (!head->is_CountedLoop() || head->as_CountedLoop()->is_main_loop() || head->as_CountedLoop()->is_normal_loop()) &&
1851 !seen.test_set(head->_idx)) {
1852 IfNode* iff = find_unswitching_candidate(loop, phase);
1853 if (iff != nullptr) {
1854 Node* bol = iff->in(1);
1855 if (head->as_Loop()->is_strip_mined()) {
1856 head->as_Loop()->verify_strip_mined(0);
1857 }
1858 move_gc_state_test_out_of_loop(iff, phase);
1859
1860 AutoNodeBudget node_budget(phase);
1861
1862 if (loop->policy_unswitching(phase)) {
1863 if (head->as_Loop()->is_strip_mined()) {
1864 OuterStripMinedLoopNode* outer = head->as_CountedLoop()->outer_loop();
1865 hide_strip_mined_loop(outer, head->as_CountedLoop(), phase);
1866 }
1867 phase->do_unswitching(loop, old_new);
1868 } else {
1869 // Not proceeding with unswitching. Move load back in
1870 // the loop.
1871 phase->igvn().replace_input_of(iff, 1, bol);
1872 }
1873 }
1874 }
1875 }
1876 }
1877 }
1878 }
1879
1880 ShenandoahIUBarrierNode::ShenandoahIUBarrierNode(Node* val) : Node(nullptr, val) {
1881 ShenandoahBarrierSetC2::bsc2()->state()->add_iu_barrier(this);
1882 }
1883
1884 const Type* ShenandoahIUBarrierNode::bottom_type() const {
1885 if (in(1) == nullptr || in(1)->is_top()) {
1886 return Type::TOP;
1887 }
1888 const Type* t = in(1)->bottom_type();
1889 if (t == TypePtr::NULL_PTR) {
1890 return t;
1891 }
1892 return t->is_oopptr();
1893 }
1894
1895 const Type* ShenandoahIUBarrierNode::Value(PhaseGVN* phase) const {
1896 if (in(1) == nullptr) {
1897 return Type::TOP;
1898 }
1899 const Type* t = phase->type(in(1));
1900 if (t == Type::TOP) {
1901 return Type::TOP;
1902 }
1903 if (t == TypePtr::NULL_PTR) {
1904 return t;
1905 }
1906 return t->is_oopptr();
1907 }
1908
1909 int ShenandoahIUBarrierNode::needed(Node* n) {
1910 if (n == nullptr ||
1911 n->is_Allocate() ||
1912 n->Opcode() == Op_ShenandoahIUBarrier ||
1913 n->bottom_type() == TypePtr::NULL_PTR ||
1914 (n->bottom_type()->make_oopptr() != nullptr && n->bottom_type()->make_oopptr()->const_oop() != nullptr)) {
1915 return NotNeeded;
1916 }
1917 if (n->is_Phi() ||
1918 n->is_CMove()) {
1919 return MaybeNeeded;
1920 }
1921 return Needed;
1922 }
1923
1924 Node* ShenandoahIUBarrierNode::next(Node* n) {
1925 for (;;) {
1926 if (n == nullptr) {
1927 return n;
1928 } else if (n->bottom_type() == TypePtr::NULL_PTR) {
1929 return n;
1930 } else if (n->bottom_type()->make_oopptr() != nullptr && n->bottom_type()->make_oopptr()->const_oop() != nullptr) {
1931 return n;
1932 } else if (n->is_ConstraintCast() ||
1933 n->Opcode() == Op_DecodeN ||
1934 n->Opcode() == Op_EncodeP) {
1935 n = n->in(1);
1936 } else if (n->is_Proj()) {
1937 n = n->in(0);
1938 } else {
1939 return n;
1940 }
1941 }
1942 ShouldNotReachHere();
1943 return nullptr;
1944 }
1945
1946 Node* ShenandoahIUBarrierNode::Identity(PhaseGVN* phase) {
1947 PhaseIterGVN* igvn = phase->is_IterGVN();
1948
1949 Node* n = next(in(1));
1950
1951 int cont = needed(n);
1952
1953 if (cont == NotNeeded) {
1954 return in(1);
1955 } else if (cont == MaybeNeeded) {
1956 if (igvn == nullptr) {
1957 phase->record_for_igvn(this);
1958 return this;
1959 } else {
1960 ResourceMark rm;
1961 Unique_Node_List wq;
1962 uint wq_i = 0;
1963
1964 for (;;) {
1965 if (n->is_Phi()) {
1966 for (uint i = 1; i < n->req(); i++) {
1967 Node* m = n->in(i);
1968 if (m != nullptr) {
1969 wq.push(m);
1970 }
1971 }
1972 } else {
1973 assert(n->is_CMove(), "nothing else here");
1974 Node* m = n->in(CMoveNode::IfFalse);
1975 wq.push(m);
1976 m = n->in(CMoveNode::IfTrue);
1977 wq.push(m);
1978 }
1979 Node* orig_n = nullptr;
1980 do {
1981 if (wq_i >= wq.size()) {
1982 return in(1);
1983 }
1984 n = wq.at(wq_i);
1985 wq_i++;
1986 orig_n = n;
1987 n = next(n);
1988 cont = needed(n);
1989 if (cont == Needed) {
1990 return this;
1991 }
1992 } while (cont != MaybeNeeded || (orig_n != n && wq.member(n)));
1993 }
1994 }
1995 }
1996
1997 return this;
1998 }
1999
2000 #ifdef ASSERT
2001 static bool has_never_branch(Node* root) {
2002 for (uint i = 1; i < root->req(); i++) {
2003 Node* in = root->in(i);
2004 if (in != nullptr && in->Opcode() == Op_Halt && in->in(0)->is_Proj() && in->in(0)->in(0)->is_NeverBranch()) {
2005 return true;
2006 }
2007 }
2008 return false;
2009 }
2010 #endif
2011
2012 void MemoryGraphFixer::collect_memory_nodes() {
2013 Node_Stack stack(0);
2014 VectorSet visited;
2015 Node_List regions;
2016
2017 // Walk the raw memory graph and create a mapping from CFG node to
2018 // memory node. Exclude phis for now.
2019 stack.push(_phase->C->root(), 1);
2020 do {
2021 Node* n = stack.node();
2022 int opc = n->Opcode();
2023 uint i = stack.index();
2024 if (i < n->req()) {
2025 Node* mem = nullptr;
2026 if (opc == Op_Root) {
2027 Node* in = n->in(i);
2028 int in_opc = in->Opcode();
2029 if (in_opc == Op_Return || in_opc == Op_Rethrow) {
2030 mem = in->in(TypeFunc::Memory);
2031 } else if (in_opc == Op_Halt) {
2032 if (in->in(0)->is_Region()) {
2033 Node* r = in->in(0);
2034 for (uint j = 1; j < r->req(); j++) {
2035 assert(!r->in(j)->is_NeverBranch(), "");
2036 }
2037 } else {
2038 Node* proj = in->in(0);
2039 assert(proj->is_Proj(), "");
2040 Node* in = proj->in(0);
2041 assert(in->is_CallStaticJava() || in->is_NeverBranch() || in->Opcode() == Op_Catch || proj->is_IfProj(), "");
2042 if (in->is_CallStaticJava()) {
2043 mem = in->in(TypeFunc::Memory);
2044 } else if (in->Opcode() == Op_Catch) {
2045 Node* call = in->in(0)->in(0);
2046 assert(call->is_Call(), "");
2047 mem = call->in(TypeFunc::Memory);
2048 } else if (in->is_NeverBranch()) {
2049 mem = collect_memory_for_infinite_loop(in);
2050 }
2051 }
2052 } else {
2053 #ifdef ASSERT
2054 n->dump();
2055 in->dump();
2056 #endif
2057 ShouldNotReachHere();
2058 }
2059 } else {
2060 assert(n->is_Phi() && n->bottom_type() == Type::MEMORY, "");
2061 assert(n->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(n->adr_type()) == _alias, "");
2062 mem = n->in(i);
2063 }
2064 i++;
2065 stack.set_index(i);
2066 if (mem == nullptr) {
2067 continue;
2068 }
2069 for (;;) {
2070 if (visited.test_set(mem->_idx) || mem->is_Start()) {
2071 break;
2072 }
2073 if (mem->is_Phi()) {
2074 stack.push(mem, 2);
2075 mem = mem->in(1);
2076 } else if (mem->is_Proj()) {
2077 stack.push(mem, mem->req());
2078 mem = mem->in(0);
2079 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
2080 mem = mem->in(TypeFunc::Memory);
2081 } else if (mem->is_MergeMem()) {
2082 MergeMemNode* mm = mem->as_MergeMem();
2083 mem = mm->memory_at(_alias);
2084 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
2085 assert(_alias == Compile::AliasIdxRaw, "");
2086 stack.push(mem, mem->req());
2087 mem = mem->in(MemNode::Memory);
2088 } else {
2089 #ifdef ASSERT
2090 mem->dump();
2091 #endif
2092 ShouldNotReachHere();
2093 }
2094 }
2095 } else {
2096 if (n->is_Phi()) {
2097 // Nothing
2098 } else if (!n->is_Root()) {
2099 Node* c = get_ctrl(n);
2100 _memory_nodes.map(c->_idx, n);
2101 }
2102 stack.pop();
2103 }
2104 } while(stack.is_nonempty());
2105
2106 // Iterate over CFG nodes in rpo and propagate memory state to
2107 // compute memory state at regions, creating new phis if needed.
2108 Node_List rpo_list;
2109 visited.clear();
2110 _phase->rpo(_phase->C->root(), stack, visited, rpo_list);
2111 Node* root = rpo_list.pop();
2112 assert(root == _phase->C->root(), "");
2113
2114 const bool trace = false;
2115 #ifdef ASSERT
2116 if (trace) {
2117 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2118 Node* c = rpo_list.at(i);
2119 if (_memory_nodes[c->_idx] != nullptr) {
2120 tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump();
2121 }
2122 }
2123 }
2124 #endif
2125 uint last = _phase->C->unique();
2126
2127 #ifdef ASSERT
2128 uint16_t max_depth = 0;
2129 for (LoopTreeIterator iter(_phase->ltree_root()); !iter.done(); iter.next()) {
2130 IdealLoopTree* lpt = iter.current();
2131 max_depth = MAX2(max_depth, lpt->_nest);
2132 }
2133 #endif
2134
2135 bool progress = true;
2136 int iteration = 0;
2137 Node_List dead_phis;
2138 while (progress) {
2139 progress = false;
2140 iteration++;
2141 assert(iteration <= 2+max_depth || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "");
2142 if (trace) { tty->print_cr("XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"); }
2143
2144 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2145 Node* c = rpo_list.at(i);
2146
2147 Node* prev_mem = _memory_nodes[c->_idx];
2148 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2149 Node* prev_region = regions[c->_idx];
2150 Node* unique = nullptr;
2151 for (uint j = 1; j < c->req() && unique != NodeSentinel; j++) {
2152 Node* m = _memory_nodes[c->in(j)->_idx];
2153 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");
2154 if (m != nullptr) {
2155 if (m == prev_region && ((c->is_Loop() && j == LoopNode::LoopBackControl) || (prev_region->is_Phi() && prev_region->in(0) == c))) {
2156 assert(c->is_Loop() && j == LoopNode::LoopBackControl || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "");
2157 // continue
2158 } else if (unique == nullptr) {
2159 unique = m;
2160 } else if (m == unique) {
2161 // continue
2162 } else {
2163 unique = NodeSentinel;
2164 }
2165 }
2166 }
2167 assert(unique != nullptr, "empty phi???");
2168 if (unique != NodeSentinel) {
2169 if (prev_region != nullptr && prev_region->is_Phi() && prev_region->in(0) == c) {
2170 dead_phis.push(prev_region);
2171 }
2172 regions.map(c->_idx, unique);
2173 } else {
2174 Node* phi = nullptr;
2175 if (prev_region != nullptr && prev_region->is_Phi() && prev_region->in(0) == c && prev_region->_idx >= last) {
2176 phi = prev_region;
2177 for (uint k = 1; k < c->req(); k++) {
2178 Node* m = _memory_nodes[c->in(k)->_idx];
2179 assert(m != nullptr, "expect memory state");
2180 phi->set_req(k, m);
2181 }
2182 } else {
2183 for (DUIterator_Fast jmax, j = c->fast_outs(jmax); j < jmax && phi == nullptr; j++) {
2184 Node* u = c->fast_out(j);
2185 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2186 (u->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(u->adr_type()) == _alias)) {
2187 phi = u;
2188 for (uint k = 1; k < c->req() && phi != nullptr; k++) {
2189 Node* m = _memory_nodes[c->in(k)->_idx];
2190 assert(m != nullptr, "expect memory state");
2191 if (u->in(k) != m) {
2192 phi = NodeSentinel;
2193 }
2194 }
2195 }
2196 }
2197 if (phi == NodeSentinel) {
2198 phi = new PhiNode(c, Type::MEMORY, _phase->C->get_adr_type(_alias));
2199 for (uint k = 1; k < c->req(); k++) {
2200 Node* m = _memory_nodes[c->in(k)->_idx];
2201 assert(m != nullptr, "expect memory state");
2202 phi->init_req(k, m);
2203 }
2204 }
2205 }
2206 if (phi != nullptr) {
2207 regions.map(c->_idx, phi);
2208 } else {
2209 assert(c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
2210 }
2211 }
2212 Node* current_region = regions[c->_idx];
2213 if (current_region != prev_region) {
2214 progress = true;
2215 if (prev_region == prev_mem) {
2216 _memory_nodes.map(c->_idx, current_region);
2217 }
2218 }
2219 } else if (prev_mem == nullptr || prev_mem->is_Phi() || ctrl_or_self(prev_mem) != c) {
2220 Node* m = _memory_nodes[_phase->idom(c)->_idx];
2221 assert(m != nullptr || c->Opcode() == Op_Halt, "expect memory state");
2222 if (m != prev_mem) {
2223 _memory_nodes.map(c->_idx, m);
2224 progress = true;
2225 }
2226 }
2227 #ifdef ASSERT
2228 if (trace) { tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump(); }
2229 #endif
2230 }
2231 }
2232
2233 // Replace existing phi with computed memory state for that region
2234 // if different (could be a new phi or a dominating memory node if
2235 // that phi was found to be useless).
2236 while (dead_phis.size() > 0) {
2237 Node* n = dead_phis.pop();
2238 n->replace_by(_phase->C->top());
2239 n->destruct(&_phase->igvn());
2240 }
2241 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2242 Node* c = rpo_list.at(i);
2243 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2244 Node* n = regions[c->_idx];
2245 assert(n != nullptr || c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
2246 if (n != nullptr && n->is_Phi() && n->_idx >= last && n->in(0) == c) {
2247 _phase->register_new_node(n, c);
2248 }
2249 }
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 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
2257 Node* u = c->fast_out(i);
2258 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2259 u != n) {
2260 assert(c->unique_ctrl_out()->Opcode() != Op_Halt, "expected memory state");
2261 if (u->adr_type() == TypePtr::BOTTOM) {
2262 fix_memory_uses(u, n, n, c);
2263 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2264 _phase->lazy_replace(u, n);
2265 --i; --imax;
2266 }
2267 }
2268 }
2269 }
2270 }
2271 }
2272
2273 Node* MemoryGraphFixer::collect_memory_for_infinite_loop(const Node* in) {
2274 Node* mem = nullptr;
2275 Node* head = in->in(0);
2276 assert(head->is_Region(), "unexpected infinite loop graph shape");
2277
2278 Node* phi_mem = nullptr;
2279 for (DUIterator_Fast jmax, j = head->fast_outs(jmax); j < jmax; j++) {
2280 Node* u = head->fast_out(j);
2281 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
2282 if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2283 assert(phi_mem == nullptr || phi_mem->adr_type() == TypePtr::BOTTOM, "");
2284 phi_mem = u;
2285 } else if (u->adr_type() == TypePtr::BOTTOM) {
2286 assert(phi_mem == nullptr || _phase->C->get_alias_index(phi_mem->adr_type()) == _alias, "");
2287 if (phi_mem == nullptr) {
2288 phi_mem = u;
2289 }
2290 }
2291 }
2292 }
2293 if (phi_mem == nullptr) {
2294 ResourceMark rm;
2295 Node_Stack stack(0);
2296 stack.push(head, 1);
2297 do {
2298 Node* n = stack.node();
2299 uint i = stack.index();
2300 if (i >= n->req()) {
2301 stack.pop();
2302 } else {
2303 stack.set_index(i + 1);
2304 Node* c = n->in(i);
2305 assert(c != head, "should have found a safepoint on the way");
2306 if (stack.size() != 1 || _phase->is_dominator(head, c)) {
2307 for (;;) {
2308 if (c->is_Region()) {
2309 stack.push(c, 1);
2310 break;
2311 } else if (c->is_SafePoint() && !c->is_CallLeaf()) {
2312 Node* m = c->in(TypeFunc::Memory);
2313 if (m->is_MergeMem()) {
2314 m = m->as_MergeMem()->memory_at(_alias);
2315 }
2316 assert(mem == nullptr || mem == m, "several memory states");
2317 mem = m;
2318 break;
2319 } else {
2320 assert(c != c->in(0), "");
2321 c = c->in(0);
2322 }
2323 }
2324 }
2325 }
2326 } while (stack.size() > 0);
2327 assert(mem != nullptr, "should have found safepoint");
2328 } else {
2329 mem = phi_mem;
2330 }
2331 return mem;
2332 }
2333
2334 Node* MemoryGraphFixer::get_ctrl(Node* n) const {
2335 Node* c = _phase->get_ctrl(n);
2336 if (n->is_Proj() && n->in(0) != nullptr && n->in(0)->is_Call()) {
2337 assert(c == n->in(0), "");
2338 CallNode* call = c->as_Call();
2339 CallProjections* projs = call->extract_projections(true, false);
2340 if (projs->catchall_memproj != nullptr) {
2341 if (projs->fallthrough_memproj == n) {
2342 c = projs->fallthrough_catchproj;
2343 } else {
2344 assert(projs->catchall_memproj == n, "");
2345 c = projs->catchall_catchproj;
2346 }
2347 }
2348 }
2349 return c;
2350 }
2351
2352 Node* MemoryGraphFixer::ctrl_or_self(Node* n) const {
2353 if (_phase->has_ctrl(n))
2354 return get_ctrl(n);
2355 else {
2356 assert (n->is_CFG(), "must be a CFG node");
2357 return n;
2358 }
2359 }
2360
2361 bool MemoryGraphFixer::mem_is_valid(Node* m, Node* c) const {
2362 return m != nullptr && get_ctrl(m) == c;
2363 }
2364
2365 Node* MemoryGraphFixer::find_mem(Node* ctrl, Node* n) const {
2366 assert(n == nullptr || _phase->ctrl_or_self(n) == ctrl, "");
2367 assert(!ctrl->is_Call() || ctrl == n, "projection expected");
2368 #ifdef ASSERT
2369 if ((ctrl->is_Proj() && ctrl->in(0)->is_Call()) ||
2370 (ctrl->is_Catch() && ctrl->in(0)->in(0)->is_Call())) {
2371 CallNode* call = ctrl->is_Proj() ? ctrl->in(0)->as_Call() : ctrl->in(0)->in(0)->as_Call();
2372 int mems = 0;
2373 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) {
2374 Node* u = call->fast_out(i);
2375 if (u->bottom_type() == Type::MEMORY) {
2376 mems++;
2377 }
2378 }
2379 assert(mems <= 1, "No node right after call if multiple mem projections");
2380 }
2381 #endif
2382 Node* mem = _memory_nodes[ctrl->_idx];
2383 Node* c = ctrl;
2384 while (!mem_is_valid(mem, c) &&
2385 (!c->is_CatchProj() || mem == nullptr || c->in(0)->in(0)->in(0) != get_ctrl(mem))) {
2386 c = _phase->idom(c);
2387 mem = _memory_nodes[c->_idx];
2388 }
2389 if (n != nullptr && mem_is_valid(mem, c)) {
2390 while (!ShenandoahBarrierC2Support::is_dominator_same_ctrl(c, mem, n, _phase) && _phase->ctrl_or_self(mem) == ctrl) {
2391 mem = next_mem(mem, _alias);
2392 }
2393 if (mem->is_MergeMem()) {
2394 mem = mem->as_MergeMem()->memory_at(_alias);
2395 }
2396 if (!mem_is_valid(mem, c)) {
2397 do {
2398 c = _phase->idom(c);
2399 mem = _memory_nodes[c->_idx];
2400 } while (!mem_is_valid(mem, c) &&
2401 (!c->is_CatchProj() || mem == nullptr || c->in(0)->in(0)->in(0) != get_ctrl(mem)));
2402 }
2403 }
2404 assert(mem->bottom_type() == Type::MEMORY, "");
2405 return mem;
2406 }
2407
2408 bool MemoryGraphFixer::has_mem_phi(Node* region) const {
2409 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
2410 Node* use = region->fast_out(i);
2411 if (use->is_Phi() && use->bottom_type() == Type::MEMORY &&
2412 (_phase->C->get_alias_index(use->adr_type()) == _alias)) {
2413 return true;
2414 }
2415 }
2416 return false;
2417 }
2418
2419 void MemoryGraphFixer::fix_mem(Node* ctrl, Node* new_ctrl, Node* mem, Node* mem_for_ctrl, Node* new_mem, Unique_Node_List& uses) {
2420 assert(_phase->ctrl_or_self(new_mem) == new_ctrl, "");
2421 const bool trace = false;
2422 DEBUG_ONLY(if (trace) { tty->print("ZZZ control is"); ctrl->dump(); });
2423 DEBUG_ONLY(if (trace) { tty->print("ZZZ mem is"); mem->dump(); });
2424 GrowableArray<Node*> phis;
2425 if (mem_for_ctrl != mem) {
2426 Node* old = mem_for_ctrl;
2427 Node* prev = nullptr;
2428 while (old != mem) {
2429 prev = old;
2430 if (old->is_Store() || old->is_ClearArray() || old->is_LoadStore()) {
2431 assert(_alias == Compile::AliasIdxRaw, "");
2432 old = old->in(MemNode::Memory);
2433 } else if (old->Opcode() == Op_SCMemProj) {
2434 assert(_alias == Compile::AliasIdxRaw, "");
2435 old = old->in(0);
2436 } else {
2437 ShouldNotReachHere();
2438 }
2439 }
2440 assert(prev != nullptr, "");
2441 if (new_ctrl != ctrl) {
2442 _memory_nodes.map(ctrl->_idx, mem);
2443 _memory_nodes.map(new_ctrl->_idx, mem_for_ctrl);
2444 }
2445 uint input = (uint)MemNode::Memory;
2446 _phase->igvn().replace_input_of(prev, input, new_mem);
2447 } else {
2448 uses.clear();
2449 _memory_nodes.map(new_ctrl->_idx, new_mem);
2450 uses.push(new_ctrl);
2451 for(uint next = 0; next < uses.size(); next++ ) {
2452 Node *n = uses.at(next);
2453 assert(n->is_CFG(), "");
2454 DEBUG_ONLY(if (trace) { tty->print("ZZZ ctrl"); n->dump(); });
2455 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2456 Node* u = n->fast_out(i);
2457 if (!u->is_Root() && u->is_CFG() && u != n) {
2458 Node* m = _memory_nodes[u->_idx];
2459 if (u->is_Region() && (!u->is_OuterStripMinedLoop() || _include_lsm) &&
2460 !has_mem_phi(u) &&
2461 u->unique_ctrl_out()->Opcode() != Op_Halt) {
2462 DEBUG_ONLY(if (trace) { tty->print("ZZZ region"); u->dump(); });
2463 DEBUG_ONLY(if (trace && m != nullptr) { tty->print("ZZZ mem"); m->dump(); });
2464
2465 if (!mem_is_valid(m, u) || !m->is_Phi()) {
2466 bool push = true;
2467 bool create_phi = true;
2468 if (_phase->is_dominator(new_ctrl, u)) {
2469 create_phi = false;
2470 }
2471 if (create_phi) {
2472 Node* phi = new PhiNode(u, Type::MEMORY, _phase->C->get_adr_type(_alias));
2473 _phase->register_new_node(phi, u);
2474 phis.push(phi);
2475 DEBUG_ONLY(if (trace) { tty->print("ZZZ new phi"); phi->dump(); });
2476 if (!mem_is_valid(m, u)) {
2477 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting mem"); phi->dump(); });
2478 _memory_nodes.map(u->_idx, phi);
2479 } else {
2480 DEBUG_ONLY(if (trace) { tty->print("ZZZ NOT setting mem"); m->dump(); });
2481 for (;;) {
2482 assert(m->is_Mem() || m->is_LoadStore() || m->is_Proj(), "");
2483 Node* next = nullptr;
2484 if (m->is_Proj()) {
2485 next = m->in(0);
2486 } else {
2487 assert(m->is_Mem() || m->is_LoadStore(), "");
2488 assert(_alias == Compile::AliasIdxRaw, "");
2489 next = m->in(MemNode::Memory);
2490 }
2491 if (_phase->get_ctrl(next) != u) {
2492 break;
2493 }
2494 if (next->is_MergeMem()) {
2495 assert(_phase->get_ctrl(next->as_MergeMem()->memory_at(_alias)) != u, "");
2496 break;
2497 }
2498 if (next->is_Phi()) {
2499 assert(next->adr_type() == TypePtr::BOTTOM && next->in(0) == u, "");
2500 break;
2501 }
2502 m = next;
2503 }
2504
2505 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting to phi"); m->dump(); });
2506 assert(m->is_Mem() || m->is_LoadStore(), "");
2507 uint input = (uint)MemNode::Memory;
2508 _phase->igvn().replace_input_of(m, input, phi);
2509 push = false;
2510 }
2511 } else {
2512 DEBUG_ONLY(if (trace) { tty->print("ZZZ skipping region"); u->dump(); });
2513 }
2514 if (push) {
2515 uses.push(u);
2516 }
2517 }
2518 } else if (!mem_is_valid(m, u) &&
2519 !(u->Opcode() == Op_CProj && u->in(0)->is_NeverBranch() && u->as_Proj()->_con == 1)) {
2520 uses.push(u);
2521 }
2522 }
2523 }
2524 }
2525 for (int i = 0; i < phis.length(); i++) {
2526 Node* n = phis.at(i);
2527 Node* r = n->in(0);
2528 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi"); n->dump(); });
2529 for (uint j = 1; j < n->req(); j++) {
2530 Node* m = find_mem(r->in(j), nullptr);
2531 _phase->igvn().replace_input_of(n, j, m);
2532 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi: %d", j); m->dump(); });
2533 }
2534 }
2535 }
2536 uint last = _phase->C->unique();
2537 MergeMemNode* mm = nullptr;
2538 int alias = _alias;
2539 DEBUG_ONLY(if (trace) { tty->print("ZZZ raw mem is"); mem->dump(); });
2540 // Process loads first to not miss an anti-dependency: if the memory
2541 // edge of a store is updated before a load is processed then an
2542 // anti-dependency may be missed.
2543 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2544 Node* u = mem->out(i);
2545 if (u->_idx < last && u->is_Load() && _phase->C->get_alias_index(u->adr_type()) == alias) {
2546 Node* m = find_mem(_phase->get_ctrl(u), u);
2547 if (m != mem) {
2548 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2549 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2550 --i;
2551 }
2552 }
2553 }
2554 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2555 Node* u = mem->out(i);
2556 if (u->_idx < last) {
2557 if (u->is_Mem()) {
2558 if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2559 Node* m = find_mem(_phase->get_ctrl(u), u);
2560 if (m != mem) {
2561 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2562 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2563 --i;
2564 }
2565 }
2566 } else if (u->is_MergeMem()) {
2567 MergeMemNode* u_mm = u->as_MergeMem();
2568 if (u_mm->memory_at(alias) == mem) {
2569 MergeMemNode* newmm = nullptr;
2570 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2571 Node* uu = u->fast_out(j);
2572 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2573 if (uu->is_Phi()) {
2574 assert(uu->adr_type() == TypePtr::BOTTOM, "");
2575 Node* region = uu->in(0);
2576 int nb = 0;
2577 for (uint k = 1; k < uu->req(); k++) {
2578 if (uu->in(k) == u) {
2579 Node* m = find_mem(region->in(k), nullptr);
2580 if (m != mem) {
2581 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", k); uu->dump(); });
2582 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2583 if (newmm != u) {
2584 _phase->igvn().replace_input_of(uu, k, newmm);
2585 nb++;
2586 --jmax;
2587 }
2588 }
2589 }
2590 }
2591 if (nb > 0) {
2592 --j;
2593 }
2594 } else {
2595 Node* m = find_mem(_phase->ctrl_or_self(uu), uu);
2596 if (m != mem) {
2597 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); uu->dump(); });
2598 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2599 if (newmm != u) {
2600 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2601 --j, --jmax;
2602 }
2603 }
2604 }
2605 }
2606 }
2607 } else if (u->is_Phi()) {
2608 assert(u->bottom_type() == Type::MEMORY, "what else?");
2609 if (_phase->C->get_alias_index(u->adr_type()) == alias || u->adr_type() == TypePtr::BOTTOM) {
2610 Node* region = u->in(0);
2611 bool replaced = false;
2612 for (uint j = 1; j < u->req(); j++) {
2613 if (u->in(j) == mem) {
2614 Node* m = find_mem(region->in(j), nullptr);
2615 Node* nnew = m;
2616 if (m != mem) {
2617 if (u->adr_type() == TypePtr::BOTTOM) {
2618 mm = allocate_merge_mem(mem, m, _phase->ctrl_or_self(m));
2619 nnew = mm;
2620 }
2621 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", j); u->dump(); });
2622 _phase->igvn().replace_input_of(u, j, nnew);
2623 replaced = true;
2624 }
2625 }
2626 }
2627 if (replaced) {
2628 --i;
2629 }
2630 }
2631 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2632 u->adr_type() == nullptr) {
2633 assert(u->adr_type() != nullptr ||
2634 u->Opcode() == Op_Rethrow ||
2635 u->Opcode() == Op_Return ||
2636 u->Opcode() == Op_SafePoint ||
2637 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2638 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2639 u->Opcode() == Op_CallLeaf, "");
2640 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2641 if (m != mem) {
2642 mm = allocate_merge_mem(mem, m, _phase->get_ctrl(m));
2643 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2644 --i;
2645 }
2646 } else if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2647 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2648 if (m != mem) {
2649 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2650 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2651 --i;
2652 }
2653 } else if (u->adr_type() != TypePtr::BOTTOM &&
2654 _memory_nodes[_phase->ctrl_or_self(u)->_idx] == u) {
2655 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2656 assert(m != mem, "");
2657 // u is on the wrong slice...
2658 assert(u->is_ClearArray(), "");
2659 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2660 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2661 --i;
2662 }
2663 }
2664 }
2665 #ifdef ASSERT
2666 assert(new_mem->outcnt() > 0, "");
2667 for (int i = 0; i < phis.length(); i++) {
2668 Node* n = phis.at(i);
2669 assert(n->outcnt() > 0, "new phi must have uses now");
2670 }
2671 #endif
2672 }
2673
2674 void MemoryGraphFixer::record_new_ctrl(Node* ctrl, Node* new_ctrl, Node* mem, Node* mem_for_ctrl) {
2675 if (mem_for_ctrl != mem && new_ctrl != ctrl) {
2676 _memory_nodes.map(ctrl->_idx, mem);
2677 _memory_nodes.map(new_ctrl->_idx, mem_for_ctrl);
2678 }
2679 }
2680
2681 MergeMemNode* MemoryGraphFixer::allocate_merge_mem(Node* mem, Node* rep_proj, Node* rep_ctrl) const {
2682 MergeMemNode* mm = MergeMemNode::make(mem);
2683 mm->set_memory_at(_alias, rep_proj);
2684 _phase->register_new_node(mm, rep_ctrl);
2685 return mm;
2686 }
2687
2688 MergeMemNode* MemoryGraphFixer::clone_merge_mem(Node* u, Node* mem, Node* rep_proj, Node* rep_ctrl, DUIterator& i) const {
2689 MergeMemNode* newmm = nullptr;
2690 MergeMemNode* u_mm = u->as_MergeMem();
2691 Node* c = _phase->get_ctrl(u);
2692 if (_phase->is_dominator(c, rep_ctrl)) {
2693 c = rep_ctrl;
2694 } else {
2695 assert(_phase->is_dominator(rep_ctrl, c), "one must dominate the other");
2696 }
2697 if (u->outcnt() == 1) {
2698 if (u->req() > (uint)_alias && u->in(_alias) == mem) {
2699 _phase->igvn().replace_input_of(u, _alias, rep_proj);
2700 --i;
2701 } else {
2702 _phase->igvn().rehash_node_delayed(u);
2703 u_mm->set_memory_at(_alias, rep_proj);
2704 }
2705 newmm = u_mm;
2706 _phase->set_ctrl_and_loop(u, c);
2707 } else {
2708 // can't simply clone u and then change one of its input because
2709 // it adds and then removes an edge which messes with the
2710 // DUIterator
2711 newmm = MergeMemNode::make(u_mm->base_memory());
2712 for (uint j = 0; j < u->req(); j++) {
2713 if (j < newmm->req()) {
2714 if (j == (uint)_alias) {
2715 newmm->set_req(j, rep_proj);
2716 } else if (newmm->in(j) != u->in(j)) {
2717 newmm->set_req(j, u->in(j));
2718 }
2719 } else if (j == (uint)_alias) {
2720 newmm->add_req(rep_proj);
2721 } else {
2722 newmm->add_req(u->in(j));
2723 }
2724 }
2725 if ((uint)_alias >= u->req()) {
2726 newmm->set_memory_at(_alias, rep_proj);
2727 }
2728 _phase->register_new_node(newmm, c);
2729 }
2730 return newmm;
2731 }
2732
2733 bool MemoryGraphFixer::should_process_phi(Node* phi) const {
2734 if (phi->adr_type() == TypePtr::BOTTOM) {
2735 Node* region = phi->in(0);
2736 for (DUIterator_Fast jmax, j = region->fast_outs(jmax); j < jmax; j++) {
2737 Node* uu = region->fast_out(j);
2738 if (uu->is_Phi() && uu != phi && uu->bottom_type() == Type::MEMORY && _phase->C->get_alias_index(uu->adr_type()) == _alias) {
2739 return false;
2740 }
2741 }
2742 return true;
2743 }
2744 return _phase->C->get_alias_index(phi->adr_type()) == _alias;
2745 }
2746
2747 void MemoryGraphFixer::fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl) const {
2748 uint last = _phase-> C->unique();
2749 MergeMemNode* mm = nullptr;
2750 assert(mem->bottom_type() == Type::MEMORY, "");
2751 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2752 Node* u = mem->out(i);
2753 if (u != replacement && u->_idx < last) {
2754 if (u->is_MergeMem()) {
2755 MergeMemNode* u_mm = u->as_MergeMem();
2756 if (u_mm->memory_at(_alias) == mem) {
2757 MergeMemNode* newmm = nullptr;
2758 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2759 Node* uu = u->fast_out(j);
2760 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2761 if (uu->is_Phi()) {
2762 if (should_process_phi(uu)) {
2763 Node* region = uu->in(0);
2764 int nb = 0;
2765 for (uint k = 1; k < uu->req(); k++) {
2766 if (uu->in(k) == u && _phase->is_dominator(rep_ctrl, region->in(k))) {
2767 if (newmm == nullptr) {
2768 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2769 }
2770 if (newmm != u) {
2771 _phase->igvn().replace_input_of(uu, k, newmm);
2772 nb++;
2773 --jmax;
2774 }
2775 }
2776 }
2777 if (nb > 0) {
2778 --j;
2779 }
2780 }
2781 } else {
2782 if (rep_ctrl != uu && ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(uu), replacement, uu, _phase)) {
2783 if (newmm == nullptr) {
2784 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2785 }
2786 if (newmm != u) {
2787 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2788 --j, --jmax;
2789 }
2790 }
2791 }
2792 }
2793 }
2794 } else if (u->is_Phi()) {
2795 assert(u->bottom_type() == Type::MEMORY, "what else?");
2796 Node* region = u->in(0);
2797 if (should_process_phi(u)) {
2798 bool replaced = false;
2799 for (uint j = 1; j < u->req(); j++) {
2800 if (u->in(j) == mem && _phase->is_dominator(rep_ctrl, region->in(j))) {
2801 Node* nnew = rep_proj;
2802 if (u->adr_type() == TypePtr::BOTTOM) {
2803 if (mm == nullptr) {
2804 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2805 }
2806 nnew = mm;
2807 }
2808 _phase->igvn().replace_input_of(u, j, nnew);
2809 replaced = true;
2810 }
2811 }
2812 if (replaced) {
2813 --i;
2814 }
2815
2816 }
2817 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2818 u->adr_type() == nullptr) {
2819 assert(u->adr_type() != nullptr ||
2820 u->Opcode() == Op_Rethrow ||
2821 u->Opcode() == Op_Return ||
2822 u->Opcode() == Op_SafePoint ||
2823 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2824 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2825 u->Opcode() == Op_CallLeaf, "%s", u->Name());
2826 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2827 if (mm == nullptr) {
2828 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2829 }
2830 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2831 --i;
2832 }
2833 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2834 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2835 _phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
2836 --i;
2837 }
2838 }
2839 }
2840 }
2841 }
2842
2843 ShenandoahLoadReferenceBarrierNode::ShenandoahLoadReferenceBarrierNode(Node* ctrl, Node* obj, DecoratorSet decorators)
2844 : Node(ctrl, obj), _decorators(decorators) {
2845 ShenandoahBarrierSetC2::bsc2()->state()->add_load_reference_barrier(this);
2846 }
2847
2848 DecoratorSet ShenandoahLoadReferenceBarrierNode::decorators() const {
2849 return _decorators;
2850 }
2851
2852 uint ShenandoahLoadReferenceBarrierNode::size_of() const {
2853 return sizeof(*this);
2854 }
2855
2856 static DecoratorSet mask_decorators(DecoratorSet decorators) {
2857 return decorators & (ON_STRONG_OOP_REF | ON_WEAK_OOP_REF | ON_PHANTOM_OOP_REF | ON_UNKNOWN_OOP_REF | IN_NATIVE);
2858 }
2859
2860 uint ShenandoahLoadReferenceBarrierNode::hash() const {
2861 uint hash = Node::hash();
2862 hash += mask_decorators(_decorators);
2863 return hash;
2864 }
2865
2866 bool ShenandoahLoadReferenceBarrierNode::cmp( const Node &n ) const {
2867 return Node::cmp(n) && n.Opcode() == Op_ShenandoahLoadReferenceBarrier &&
2868 mask_decorators(_decorators) == mask_decorators(((const ShenandoahLoadReferenceBarrierNode&)n)._decorators);
2869 }
2870
2871 const Type* ShenandoahLoadReferenceBarrierNode::bottom_type() const {
2872 if (in(ValueIn) == nullptr || in(ValueIn)->is_top()) {
2873 return Type::TOP;
2874 }
2875 const Type* t = in(ValueIn)->bottom_type();
2876 if (t == TypePtr::NULL_PTR) {
2877 return t;
2878 }
2879
2880 if (ShenandoahBarrierSet::is_strong_access(decorators())) {
2881 return t;
2882 }
2883
2884 return t->meet(TypePtr::NULL_PTR);
2885 }
2886
2887 const Type* ShenandoahLoadReferenceBarrierNode::Value(PhaseGVN* phase) const {
2888 // Either input is TOP ==> the result is TOP
2889 const Type *t2 = phase->type(in(ValueIn));
2890 if( t2 == Type::TOP ) return Type::TOP;
2891
2892 if (t2 == TypePtr::NULL_PTR) {
2893 return t2;
2894 }
2895
2896 if (ShenandoahBarrierSet::is_strong_access(decorators())) {
2897 return t2;
2898 }
2899
2900 return t2->meet(TypePtr::NULL_PTR);
2901 }
2902
2903 Node* ShenandoahLoadReferenceBarrierNode::Identity(PhaseGVN* phase) {
2904 Node* value = in(ValueIn);
2905 if (!needs_barrier(phase, value)) {
2906 return value;
2907 }
2908 return this;
2909 }
2910
2911 bool ShenandoahLoadReferenceBarrierNode::needs_barrier(PhaseGVN* phase, Node* n) {
2912 Unique_Node_List visited;
2913 return needs_barrier_impl(phase, n, visited);
2914 }
2915
2916 bool ShenandoahLoadReferenceBarrierNode::needs_barrier_impl(PhaseGVN* phase, Node* n, Unique_Node_List &visited) {
2917 if (n == nullptr) return false;
2918 if (visited.member(n)) {
2919 return false; // Been there.
2920 }
2921 visited.push(n);
2922
2923 if (n->is_Allocate()) {
2924 // tty->print_cr("optimize barrier on alloc");
2925 return false;
2926 }
2927 if (n->is_Call()) {
2928 // tty->print_cr("optimize barrier on call");
2929 return false;
2930 }
2931
2932 const Type* type = phase->type(n);
2933 if (type == Type::TOP) {
2934 return false;
2935 }
2936 if (type->make_ptr()->higher_equal(TypePtr::NULL_PTR)) {
2937 // tty->print_cr("optimize barrier on null");
2938 return false;
2939 }
2940 if (type->make_oopptr() && type->make_oopptr()->const_oop() != nullptr) {
2941 // tty->print_cr("optimize barrier on constant");
2942 return false;
2943 }
2944
2945 switch (n->Opcode()) {
2946 case Op_AddP:
2947 return true; // TODO: Can refine?
2948 case Op_LoadP:
2949 case Op_ShenandoahCompareAndExchangeN:
2950 case Op_ShenandoahCompareAndExchangeP:
2951 case Op_CompareAndExchangeN:
2952 case Op_CompareAndExchangeP:
2953 case Op_GetAndSetN:
2954 case Op_GetAndSetP:
2955 return true;
2956 case Op_Phi: {
2957 for (uint i = 1; i < n->req(); i++) {
2958 if (needs_barrier_impl(phase, n->in(i), visited)) return true;
2959 }
2960 return false;
2961 }
2962 case Op_CheckCastPP:
2963 case Op_CastPP:
2964 return needs_barrier_impl(phase, n->in(1), visited);
2965 case Op_Proj:
2966 return needs_barrier_impl(phase, n->in(0), visited);
2967 case Op_ShenandoahLoadReferenceBarrier:
2968 // tty->print_cr("optimize barrier on barrier");
2969 return false;
2970 case Op_Parm:
2971 // tty->print_cr("optimize barrier on input arg");
2972 return false;
2973 case Op_DecodeN:
2974 case Op_EncodeP:
2975 return needs_barrier_impl(phase, n->in(1), visited);
2976 case Op_LoadN:
2977 return true;
2978 case Op_CMoveN:
2979 case Op_CMoveP:
2980 return needs_barrier_impl(phase, n->in(2), visited) ||
2981 needs_barrier_impl(phase, n->in(3), visited);
2982 case Op_ShenandoahIUBarrier:
2983 return needs_barrier_impl(phase, n->in(1), visited);
2984 case Op_CreateEx:
2985 return false;
2986 default:
2987 break;
2988 }
2989 #ifdef ASSERT
2990 tty->print("need barrier on?: ");
2991 tty->print_cr("ins:");
2992 n->dump(2);
2993 tty->print_cr("outs:");
2994 n->dump(-2);
2995 ShouldNotReachHere();
2996 #endif
2997 return true;
2998 }