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 C->clear_major_progress();
54 PhaseIdealLoop::optimize(igvn, LoopOptsShenandoahExpand);
55 if (C->failing()) return false;
56
57 C->set_major_progress();
58 if (!C->optimize_loops(igvn, LoopOptsShenandoahPostExpand)) {
59 return false;
60 }
61 C->clear_major_progress();
62 C->process_for_post_loop_opts_igvn(igvn);
63 if (C->failing()) return false;
64
65 C->set_post_loop_opts_phase(); // now for real!
66 }
67 return true;
68 }
69
70 bool ShenandoahBarrierC2Support::is_gc_state_test(Node* iff, int mask) {
71 if (!UseShenandoahGC) {
72 return false;
73 }
74 assert(iff->is_If(), "bad input");
75 if (iff->Opcode() != Op_If) {
76 return false;
77 }
78 Node* bol = iff->in(1);
79 if (!bol->is_Bool() || bol->as_Bool()->_test._test != BoolTest::ne) {
80 return false;
81 }
82 Node* cmp = bol->in(1);
83 if (cmp->Opcode() != Op_CmpI) {
84 return false;
85 }
86 Node* in1 = cmp->in(1);
87 Node* in2 = cmp->in(2);
88 if (in2->find_int_con(-1) != 0) {
89 return false;
90 }
91 if (in1->Opcode() != Op_AndI) {
92 return false;
93 }
94 in2 = in1->in(2);
95 if (in2->find_int_con(-1) != mask) {
96 return false;
97 }
98 in1 = in1->in(1);
99
100 return is_gc_state_load(in1);
101 }
102
103 bool ShenandoahBarrierC2Support::is_heap_stable_test(Node* iff) {
104 return is_gc_state_test(iff, ShenandoahHeap::HAS_FORWARDED);
105 }
106
107 bool ShenandoahBarrierC2Support::is_gc_state_load(Node *n) {
108 if (!UseShenandoahGC) {
109 return false;
110 }
111 if (n->Opcode() != Op_LoadB && n->Opcode() != Op_LoadUB) {
112 return false;
113 }
114 Node* addp = n->in(MemNode::Address);
115 if (!addp->is_AddP()) {
116 return false;
117 }
118 Node* base = addp->in(AddPNode::Address);
119 Node* off = addp->in(AddPNode::Offset);
120 if (base->Opcode() != Op_ThreadLocal) {
121 return false;
122 }
123 if (off->find_intptr_t_con(-1) != in_bytes(ShenandoahThreadLocalData::gc_state_offset())) {
124 return false;
125 }
126 return true;
127 }
128
129 bool ShenandoahBarrierC2Support::has_safepoint_between(Node* start, Node* stop, PhaseIdealLoop *phase) {
130 assert(phase->is_dominator(stop, start), "bad inputs");
131 ResourceMark rm;
132 Unique_Node_List wq;
133 wq.push(start);
134 for (uint next = 0; next < wq.size(); next++) {
135 Node *m = wq.at(next);
136 if (m == stop) {
137 continue;
138 }
139 if (m->is_SafePoint() && !m->is_CallLeaf()) {
140 return true;
141 }
142 if (m->is_Region()) {
143 for (uint i = 1; i < m->req(); i++) {
144 wq.push(m->in(i));
145 }
146 } else {
147 wq.push(m->in(0));
148 }
149 }
150 return false;
151 }
152
153 #ifdef ASSERT
154 bool ShenandoahBarrierC2Support::verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used) {
155 assert(phis.size() == 0, "");
156
157 while (true) {
158 if (in->bottom_type() == TypePtr::NULL_PTR) {
159 if (trace) {tty->print_cr("null");}
160 } else if (!in->bottom_type()->make_ptr()->make_oopptr()) {
161 if (trace) {tty->print_cr("Non oop");}
162 } else {
163 if (in->is_ConstraintCast()) {
164 in = in->in(1);
165 continue;
166 } else if (in->is_AddP()) {
167 assert(!in->in(AddPNode::Address)->is_top(), "no raw memory access");
168 in = in->in(AddPNode::Address);
169 continue;
170 } else if (in->is_Con()) {
171 if (trace) {
172 tty->print("Found constant");
173 in->dump();
174 }
175 } else if (in->Opcode() == Op_Parm) {
176 if (trace) {
177 tty->print("Found argument");
178 }
179 } else if (in->Opcode() == Op_CreateEx) {
180 if (trace) {
181 tty->print("Found create-exception");
182 }
183 } else if (in->Opcode() == Op_LoadP && in->adr_type() == TypeRawPtr::BOTTOM) {
184 if (trace) {
185 tty->print("Found raw LoadP (OSR argument?)");
186 }
187 } else if (in->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
188 if (t == ShenandoahOopStore) {
189 uint i = 0;
190 for (; i < phis.size(); i++) {
191 Node* n = phis.node_at(i);
192 if (n->Opcode() == Op_ShenandoahIUBarrier) {
193 break;
194 }
195 }
196 if (i == phis.size()) {
197 return false;
198 }
199 }
200 barriers_used.push(in);
201 if (trace) {tty->print("Found barrier"); in->dump();}
202 } else if (in->Opcode() == Op_ShenandoahIUBarrier) {
203 if (t != ShenandoahOopStore) {
204 in = in->in(1);
205 continue;
206 }
207 if (trace) {tty->print("Found enqueue barrier"); in->dump();}
208 phis.push(in, in->req());
209 in = in->in(1);
210 continue;
211 } else if (in->is_Proj() && in->in(0)->is_Allocate()) {
212 if (trace) {
213 tty->print("Found alloc");
214 in->in(0)->dump();
215 }
216 } else if (in->is_Proj() && (in->in(0)->Opcode() == Op_CallStaticJava || in->in(0)->Opcode() == Op_CallDynamicJava)) {
217 if (trace) {
218 tty->print("Found Java call");
219 }
220 } else if (in->is_Phi()) {
221 if (!visited.test_set(in->_idx)) {
222 if (trace) {tty->print("Pushed phi:"); in->dump();}
223 phis.push(in, 2);
224 in = in->in(1);
225 continue;
226 }
227 if (trace) {tty->print("Already seen phi:"); in->dump();}
228 } else if (in->Opcode() == Op_CMoveP || in->Opcode() == Op_CMoveN) {
229 if (!visited.test_set(in->_idx)) {
230 if (trace) {tty->print("Pushed cmovep:"); in->dump();}
231 phis.push(in, CMoveNode::IfTrue);
232 in = in->in(CMoveNode::IfFalse);
233 continue;
234 }
235 if (trace) {tty->print("Already seen cmovep:"); in->dump();}
236 } else if (in->Opcode() == Op_EncodeP || in->Opcode() == Op_DecodeN) {
237 in = in->in(1);
238 continue;
239 } else {
240 return false;
241 }
242 }
243 bool cont = false;
244 while (phis.is_nonempty()) {
245 uint idx = phis.index();
246 Node* phi = phis.node();
247 if (idx >= phi->req()) {
248 if (trace) {tty->print("Popped phi:"); phi->dump();}
249 phis.pop();
250 continue;
251 }
252 if (trace) {tty->print("Next entry(%d) for phi:", idx); phi->dump();}
253 in = phi->in(idx);
254 phis.set_index(idx+1);
255 cont = true;
256 break;
257 }
258 if (!cont) {
259 break;
260 }
261 }
262 return true;
263 }
264
265 void ShenandoahBarrierC2Support::report_verify_failure(const char* msg, Node* n1, Node* n2) {
266 if (n1 != nullptr) {
267 n1->dump(+10);
268 }
269 if (n2 != nullptr) {
270 n2->dump(+10);
271 }
272 fatal("%s", msg);
273 }
274
275 void ShenandoahBarrierC2Support::verify(RootNode* root) {
276 ResourceMark rm;
277 Unique_Node_List wq;
278 GrowableArray<Node*> barriers;
279 Unique_Node_List barriers_used;
280 Node_Stack phis(0);
281 VectorSet visited;
282 const bool trace = false;
283 const bool verify_no_useless_barrier = false;
284
285 wq.push(root);
286 for (uint next = 0; next < wq.size(); next++) {
287 Node *n = wq.at(next);
288 if (n->is_Load()) {
289 const bool trace = false;
290 if (trace) {tty->print("Verifying"); n->dump();}
291 if (n->Opcode() == Op_LoadRange || n->Opcode() == Op_LoadKlass || n->Opcode() == Op_LoadNKlass) {
292 if (trace) {tty->print_cr("Load range/klass");}
293 } else {
294 const TypePtr* adr_type = n->as_Load()->adr_type();
295
296 if (adr_type->isa_oopptr() && adr_type->is_oopptr()->offset() == oopDesc::mark_offset_in_bytes()) {
297 if (trace) {tty->print_cr("Mark load");}
298 } else if (adr_type->isa_instptr() &&
299 adr_type->is_instptr()->instance_klass()->is_subtype_of(Compile::current()->env()->Reference_klass()) &&
300 adr_type->is_instptr()->offset() == java_lang_ref_Reference::referent_offset()) {
301 if (trace) {tty->print_cr("Reference.get()");}
302 } else if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahLoad, trace, barriers_used)) {
303 report_verify_failure("Shenandoah verification: Load should have barriers", n);
304 }
305 }
306 } else if (n->is_Store()) {
307 const bool trace = false;
308
309 if (trace) {tty->print("Verifying"); n->dump();}
310 if (n->in(MemNode::ValueIn)->bottom_type()->make_oopptr()) {
311 Node* adr = n->in(MemNode::Address);
312 bool verify = true;
313
314 if (adr->is_AddP() && adr->in(AddPNode::Base)->is_top()) {
315 adr = adr->in(AddPNode::Address);
316 if (adr->is_AddP()) {
317 assert(adr->in(AddPNode::Base)->is_top(), "");
318 adr = adr->in(AddPNode::Address);
319 if (adr->Opcode() == Op_LoadP &&
320 adr->in(MemNode::Address)->in(AddPNode::Base)->is_top() &&
321 adr->in(MemNode::Address)->in(AddPNode::Address)->Opcode() == Op_ThreadLocal &&
322 adr->in(MemNode::Address)->in(AddPNode::Offset)->find_intptr_t_con(-1) == in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset())) {
323 if (trace) {tty->print_cr("SATB prebarrier");}
324 verify = false;
325 }
326 }
327 }
328
329 if (verify && !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahIUBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
330 report_verify_failure("Shenandoah verification: Store should have barriers", n);
331 }
332 }
333 if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
334 report_verify_failure("Shenandoah verification: Store (address) should have barriers", n);
335 }
336 } else if (n->Opcode() == Op_CmpP) {
337 const bool trace = false;
338
339 Node* in1 = n->in(1);
340 Node* in2 = n->in(2);
341 if (in1->bottom_type()->isa_oopptr()) {
342 if (trace) {tty->print("Verifying"); n->dump();}
343
344 bool mark_inputs = false;
345 if (in1->bottom_type() == TypePtr::NULL_PTR || in2->bottom_type() == TypePtr::NULL_PTR ||
346 (in1->is_Con() || in2->is_Con())) {
347 if (trace) {tty->print_cr("Comparison against a constant");}
348 mark_inputs = true;
349 } else if ((in1->is_CheckCastPP() && in1->in(1)->is_Proj() && in1->in(1)->in(0)->is_Allocate()) ||
350 (in2->is_CheckCastPP() && in2->in(1)->is_Proj() && in2->in(1)->in(0)->is_Allocate())) {
351 if (trace) {tty->print_cr("Comparison with newly alloc'ed object");}
352 mark_inputs = true;
353 } else {
354 assert(in2->bottom_type()->isa_oopptr(), "");
355
356 if (!verify_helper(in1, phis, visited, ShenandoahStore, trace, barriers_used) ||
357 !verify_helper(in2, phis, visited, ShenandoahStore, trace, barriers_used)) {
358 report_verify_failure("Shenandoah verification: Cmp should have barriers", n);
359 }
360 }
361 if (verify_no_useless_barrier &&
362 mark_inputs &&
363 (!verify_helper(in1, phis, visited, ShenandoahValue, trace, barriers_used) ||
364 !verify_helper(in2, phis, visited, ShenandoahValue, trace, barriers_used))) {
365 phis.clear();
366 visited.reset();
367 }
368 }
369 } else if (n->is_LoadStore()) {
370 if (n->in(MemNode::ValueIn)->bottom_type()->make_ptr() &&
371 !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahIUBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
372 report_verify_failure("Shenandoah verification: LoadStore (value) should have barriers", n);
373 }
374
375 if (n->in(MemNode::Address)->bottom_type()->make_oopptr() && !verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
376 report_verify_failure("Shenandoah verification: LoadStore (address) should have barriers", n);
377 }
378 } else if (n->Opcode() == Op_CallLeafNoFP || n->Opcode() == Op_CallLeaf) {
379 CallNode* call = n->as_Call();
380
381 static struct {
382 const char* name;
383 struct {
384 int pos;
385 verify_type t;
386 } args[6];
387 } calls[] = {
388 "array_partition_stub",
389 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+4, ShenandoahStore }, { -1, ShenandoahNone },
390 { -1, ShenandoahNone }, { -1, ShenandoahNone }, { -1, ShenandoahNone } },
391 "arraysort_stub",
392 { { TypeFunc::Parms, ShenandoahStore }, { -1, ShenandoahNone }, { -1, ShenandoahNone },
393 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
394 "aescrypt_encryptBlock",
395 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
396 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
397 "aescrypt_decryptBlock",
398 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
399 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
400 "multiplyToLen",
401 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { TypeFunc::Parms+4, ShenandoahStore },
402 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
403 "squareToLen",
404 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { -1, ShenandoahNone},
405 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
406 "montgomery_multiply",
407 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
408 { TypeFunc::Parms+6, ShenandoahStore }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
409 "montgomery_square",
410 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+5, ShenandoahStore },
411 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
412 "mulAdd",
413 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
414 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
415 "vectorizedMismatch",
416 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
417 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
418 "updateBytesCRC32",
419 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
420 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
421 "updateBytesAdler32",
422 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
423 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
424 "updateBytesCRC32C",
425 { { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahLoad}, { -1, ShenandoahNone},
426 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
427 "counterMode_AESCrypt",
428 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
429 { TypeFunc::Parms+3, ShenandoahStore }, { TypeFunc::Parms+5, ShenandoahStore }, { TypeFunc::Parms+6, ShenandoahStore } },
430 "cipherBlockChaining_encryptAESCrypt",
431 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
432 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
433 "cipherBlockChaining_decryptAESCrypt",
434 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
435 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
436 "shenandoah_clone_barrier",
437 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
438 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
439 "ghash_processBlocks",
440 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
441 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
442 "sha1_implCompress",
443 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
444 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
445 "sha256_implCompress",
446 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
447 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
448 "sha512_implCompress",
449 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
450 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
451 "sha1_implCompressMB",
452 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
453 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
454 "sha256_implCompressMB",
455 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
456 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
457 "sha512_implCompressMB",
458 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
459 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
460 "encodeBlock",
461 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
462 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
463 "decodeBlock",
464 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
465 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
466 "intpoly_montgomeryMult_P256",
467 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahStore },
468 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
469 "intpoly_assign",
470 { { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad }, { -1, ShenandoahNone },
471 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
472 };
473
474 if (call->is_call_to_arraycopystub()) {
475 Node* dest = nullptr;
476 const TypeTuple* args = n->as_Call()->_tf->domain();
477 for (uint i = TypeFunc::Parms, j = 0; i < args->cnt(); i++) {
478 if (args->field_at(i)->isa_ptr()) {
479 j++;
480 if (j == 2) {
481 dest = n->in(i);
482 break;
483 }
484 }
485 }
486 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahLoad, trace, barriers_used) ||
487 !verify_helper(dest, phis, visited, ShenandoahStore, trace, barriers_used)) {
488 report_verify_failure("Shenandoah verification: ArrayCopy should have barriers", n);
489 }
490 } else if (strlen(call->_name) > 5 &&
491 !strcmp(call->_name + strlen(call->_name) - 5, "_fill")) {
492 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahStore, trace, barriers_used)) {
493 report_verify_failure("Shenandoah verification: _fill should have barriers", n);
494 }
495 } else if (!strcmp(call->_name, "shenandoah_wb_pre")) {
496 // skip
497 } else {
498 const int calls_len = sizeof(calls) / sizeof(calls[0]);
499 int i = 0;
500 for (; i < calls_len; i++) {
501 if (!strcmp(calls[i].name, call->_name)) {
502 break;
503 }
504 }
505 if (i != calls_len) {
506 const uint args_len = sizeof(calls[0].args) / sizeof(calls[0].args[0]);
507 for (uint j = 0; j < args_len; j++) {
508 int pos = calls[i].args[j].pos;
509 if (pos == -1) {
510 break;
511 }
512 if (!verify_helper(call->in(pos), phis, visited, calls[i].args[j].t, trace, barriers_used)) {
513 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
514 }
515 }
516 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
517 if (call->in(j)->bottom_type()->make_ptr() &&
518 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
519 uint k = 0;
520 for (; k < args_len && calls[i].args[k].pos != (int)j; k++);
521 if (k == args_len) {
522 fatal("arg %d for call %s not covered", j, call->_name);
523 }
524 }
525 }
526 } else {
527 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
528 if (call->in(j)->bottom_type()->make_ptr() &&
529 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
530 fatal("%s not covered", call->_name);
531 }
532 }
533 }
534 }
535 } else if (n->Opcode() == Op_ShenandoahIUBarrier || n->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
536 // skip
537 } else if (n->is_AddP()
538 || n->is_Phi()
539 || n->is_ConstraintCast()
540 || n->Opcode() == Op_Return
541 || n->Opcode() == Op_CMoveP
542 || n->Opcode() == Op_CMoveN
543 || n->Opcode() == Op_Rethrow
544 || n->is_MemBar()
545 || n->Opcode() == Op_Conv2B
546 || n->Opcode() == Op_SafePoint
547 || n->is_CallJava()
548 || n->Opcode() == Op_Unlock
549 || n->Opcode() == Op_EncodeP
550 || n->Opcode() == Op_DecodeN) {
551 // nothing to do
552 } else {
553 static struct {
554 int opcode;
555 struct {
556 int pos;
557 verify_type t;
558 } inputs[2];
559 } others[] = {
560 Op_FastLock,
561 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
562 Op_Lock,
563 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone} },
564 Op_ArrayCopy,
565 { { ArrayCopyNode::Src, ShenandoahLoad }, { ArrayCopyNode::Dest, ShenandoahStore } },
566 Op_StrCompressedCopy,
567 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
568 Op_StrInflatedCopy,
569 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
570 Op_AryEq,
571 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
572 Op_StrIndexOf,
573 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
574 Op_StrComp,
575 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
576 Op_StrEquals,
577 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
578 Op_VectorizedHashCode,
579 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
580 Op_EncodeISOArray,
581 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
582 Op_CountPositives,
583 { { 2, ShenandoahLoad }, { -1, ShenandoahNone} },
584 Op_CastP2X,
585 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
586 Op_StrIndexOfChar,
587 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
588 };
589
590 const int others_len = sizeof(others) / sizeof(others[0]);
591 int i = 0;
592 for (; i < others_len; i++) {
593 if (others[i].opcode == n->Opcode()) {
594 break;
595 }
596 }
597 uint stop = n->is_Call() ? n->as_Call()->tf()->domain()->cnt() : n->req();
598 if (i != others_len) {
599 const uint inputs_len = sizeof(others[0].inputs) / sizeof(others[0].inputs[0]);
600 for (uint j = 0; j < inputs_len; j++) {
601 int pos = others[i].inputs[j].pos;
602 if (pos == -1) {
603 break;
604 }
605 if (!verify_helper(n->in(pos), phis, visited, others[i].inputs[j].t, trace, barriers_used)) {
606 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
607 }
608 }
609 for (uint j = 1; j < stop; j++) {
610 if (n->in(j) != nullptr && n->in(j)->bottom_type()->make_ptr() &&
611 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
612 uint k = 0;
613 for (; k < inputs_len && others[i].inputs[k].pos != (int)j; k++);
614 if (k == inputs_len) {
615 fatal("arg %d for node %s not covered", j, n->Name());
616 }
617 }
618 }
619 } else {
620 for (uint j = 1; j < stop; j++) {
621 if (n->in(j) != nullptr && n->in(j)->bottom_type()->make_ptr() &&
622 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
623 fatal("%s not covered", n->Name());
624 }
625 }
626 }
627 }
628
629 if (n->is_SafePoint()) {
630 SafePointNode* sfpt = n->as_SafePoint();
631 if (verify_no_useless_barrier && sfpt->jvms() != nullptr) {
632 for (uint i = sfpt->jvms()->scloff(); i < sfpt->jvms()->endoff(); i++) {
633 if (!verify_helper(sfpt->in(i), phis, visited, ShenandoahLoad, trace, barriers_used)) {
634 phis.clear();
635 visited.reset();
636 }
637 }
638 }
639 }
640 }
641
642 if (verify_no_useless_barrier) {
643 for (int i = 0; i < barriers.length(); i++) {
644 Node* n = barriers.at(i);
645 if (!barriers_used.member(n)) {
646 tty->print("XXX useless barrier"); n->dump(-2);
647 ShouldNotReachHere();
648 }
649 }
650 }
651 }
652 #endif
653
654 bool ShenandoahBarrierC2Support::is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase) {
655 // That both nodes have the same control is not sufficient to prove
656 // domination, verify that there's no path from d to n
657 ResourceMark rm;
658 Unique_Node_List wq;
659 wq.push(d);
660 for (uint next = 0; next < wq.size(); next++) {
661 Node *m = wq.at(next);
662 if (m == n) {
663 return false;
664 }
665 if (m->is_Phi() && m->in(0)->is_Loop()) {
666 assert(phase->ctrl_or_self(m->in(LoopNode::EntryControl)) != c, "following loop entry should lead to new control");
667 } else {
668 if (m->is_Store() || m->is_LoadStore()) {
669 // Take anti-dependencies into account
670 Node* mem = m->in(MemNode::Memory);
671 for (DUIterator_Fast imax, i = mem->fast_outs(imax); i < imax; i++) {
672 Node* u = mem->fast_out(i);
673 if (u->is_Load() && phase->C->can_alias(m->adr_type(), phase->C->get_alias_index(u->adr_type())) &&
674 phase->ctrl_or_self(u) == c) {
675 wq.push(u);
676 }
677 }
678 }
679 for (uint i = 0; i < m->req(); i++) {
680 if (m->in(i) != nullptr && phase->ctrl_or_self(m->in(i)) == c) {
681 wq.push(m->in(i));
682 }
683 }
684 }
685 }
686 return true;
687 }
688
689 bool ShenandoahBarrierC2Support::is_dominator(Node* d_c, Node* n_c, Node* d, Node* n, PhaseIdealLoop* phase) {
690 if (d_c != n_c) {
691 return phase->is_dominator(d_c, n_c);
692 }
693 return is_dominator_same_ctrl(d_c, d, n, phase);
694 }
695
696 Node* next_mem(Node* mem, int alias) {
697 Node* res = nullptr;
698 if (mem->is_Proj()) {
699 res = mem->in(0);
700 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
701 res = mem->in(TypeFunc::Memory);
702 } else if (mem->is_Phi()) {
703 res = mem->in(1);
704 } else if (mem->is_MergeMem()) {
705 res = mem->as_MergeMem()->memory_at(alias);
706 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
707 assert(alias == Compile::AliasIdxRaw, "following raw memory can't lead to a barrier");
708 res = mem->in(MemNode::Memory);
709 } else {
710 #ifdef ASSERT
711 mem->dump();
712 #endif
713 ShouldNotReachHere();
714 }
715 return res;
716 }
717
718 Node* ShenandoahBarrierC2Support::no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase) {
719 Node* iffproj = nullptr;
720 while (c != dom) {
721 Node* next = phase->idom(c);
722 assert(next->unique_ctrl_out_or_null() == c || c->is_Proj() || c->is_Region(), "multiple control flow out but no proj or region?");
723 if (c->is_Region()) {
724 ResourceMark rm;
725 Unique_Node_List wq;
726 wq.push(c);
727 for (uint i = 0; i < wq.size(); i++) {
728 Node *n = wq.at(i);
729 if (n == next) {
730 continue;
731 }
732 if (n->is_Region()) {
733 for (uint j = 1; j < n->req(); j++) {
734 wq.push(n->in(j));
735 }
736 } else {
737 wq.push(n->in(0));
738 }
739 }
740 for (uint i = 0; i < wq.size(); i++) {
741 Node *n = wq.at(i);
742 assert(n->is_CFG(), "");
743 if (n->is_Multi()) {
744 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
745 Node* u = n->fast_out(j);
746 if (u->is_CFG()) {
747 if (!wq.member(u) && !u->as_Proj()->is_uncommon_trap_proj()) {
748 return NodeSentinel;
749 }
750 }
751 }
752 }
753 }
754 } else if (c->is_Proj()) {
755 if (c->is_IfProj()) {
756 if (c->as_Proj()->is_uncommon_trap_if_pattern() != nullptr) {
757 // continue;
758 } else {
759 if (!allow_one_proj) {
760 return NodeSentinel;
761 }
762 if (iffproj == nullptr) {
763 iffproj = c;
764 } else {
765 return NodeSentinel;
766 }
767 }
768 } else if (c->Opcode() == Op_JumpProj) {
769 return NodeSentinel; // unsupported
770 } else if (c->Opcode() == Op_CatchProj) {
771 return NodeSentinel; // unsupported
772 } else if (c->Opcode() == Op_CProj && next->is_NeverBranch()) {
773 return NodeSentinel; // unsupported
774 } else {
775 assert(next->unique_ctrl_out() == c, "unsupported branch pattern");
776 }
777 }
778 c = next;
779 }
780 return iffproj;
781 }
782
783 Node* ShenandoahBarrierC2Support::dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase) {
784 ResourceMark rm;
785 VectorSet wq;
786 wq.set(mem->_idx);
787 mem_ctrl = phase->ctrl_or_self(mem);
788 while (!phase->is_dominator(mem_ctrl, ctrl) || mem_ctrl == ctrl) {
789 mem = next_mem(mem, alias);
790 if (wq.test_set(mem->_idx)) {
791 return nullptr;
792 }
793 mem_ctrl = phase->ctrl_or_self(mem);
794 }
795 if (mem->is_MergeMem()) {
796 mem = mem->as_MergeMem()->memory_at(alias);
797 mem_ctrl = phase->ctrl_or_self(mem);
798 }
799 return mem;
800 }
801
802 Node* ShenandoahBarrierC2Support::find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase) {
803 Node* mem = nullptr;
804 Node* c = ctrl;
805 do {
806 if (c->is_Region()) {
807 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax && mem == nullptr; i++) {
808 Node* u = c->fast_out(i);
809 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
810 if (u->adr_type() == TypePtr::BOTTOM) {
811 mem = u;
812 }
813 }
814 }
815 } else {
816 if (c->is_Call() && c->as_Call()->adr_type() != nullptr) {
817 CallProjections projs;
818 c->as_Call()->extract_projections(&projs, true, false);
819 if (projs.fallthrough_memproj != nullptr) {
820 if (projs.fallthrough_memproj->adr_type() == TypePtr::BOTTOM) {
821 if (projs.catchall_memproj == nullptr) {
822 mem = projs.fallthrough_memproj;
823 } else {
824 if (phase->is_dominator(projs.fallthrough_catchproj, ctrl)) {
825 mem = projs.fallthrough_memproj;
826 } else {
827 assert(phase->is_dominator(projs.catchall_catchproj, ctrl), "one proj must dominate barrier");
828 mem = projs.catchall_memproj;
829 }
830 }
831 }
832 } else {
833 Node* proj = c->as_Call()->proj_out(TypeFunc::Memory);
834 if (proj != nullptr &&
835 proj->adr_type() == TypePtr::BOTTOM) {
836 mem = proj;
837 }
838 }
839 } else {
840 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
841 Node* u = c->fast_out(i);
842 if (u->is_Proj() &&
843 u->bottom_type() == Type::MEMORY &&
844 u->adr_type() == TypePtr::BOTTOM) {
845 assert(c->is_SafePoint() || c->is_MemBar() || c->is_Start(), "");
846 assert(mem == nullptr, "only one proj");
847 mem = u;
848 }
849 }
850 assert(!c->is_Call() || c->as_Call()->adr_type() != nullptr || mem == nullptr, "no mem projection expected");
851 }
852 }
853 c = phase->idom(c);
854 } while (mem == nullptr);
855 return mem;
856 }
857
858 void ShenandoahBarrierC2Support::follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase) {
859 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
860 Node* u = n->fast_out(i);
861 if (!u->is_CFG() && phase->get_ctrl(u) == ctrl && (!u->is_Phi() || !u->in(0)->is_Loop() || u->in(LoopNode::LoopBackControl) != n)) {
862 uses.push(u);
863 }
864 }
865 }
866
867 static void hide_strip_mined_loop(OuterStripMinedLoopNode* outer, CountedLoopNode* inner, PhaseIdealLoop* phase) {
868 OuterStripMinedLoopEndNode* le = inner->outer_loop_end();
869 Node* new_outer = new LoopNode(outer->in(LoopNode::EntryControl), outer->in(LoopNode::LoopBackControl));
870 phase->register_control(new_outer, phase->get_loop(outer), outer->in(LoopNode::EntryControl));
871 Node* new_le = new IfNode(le->in(0), le->in(1), le->_prob, le->_fcnt);
872 phase->register_control(new_le, phase->get_loop(le), le->in(0));
873 phase->lazy_replace(outer, new_outer);
874 phase->lazy_replace(le, new_le);
875 inner->clear_strip_mined();
876 }
877
878 void ShenandoahBarrierC2Support::test_gc_state(Node*& ctrl, Node* raw_mem, Node*& test_fail_ctrl,
879 PhaseIdealLoop* phase, int flags) {
880 PhaseIterGVN& igvn = phase->igvn();
881 Node* old_ctrl = ctrl;
882
883 Node* thread = new ThreadLocalNode();
884 Node* gc_state_offset = igvn.MakeConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
885 Node* gc_state_addr = new AddPNode(phase->C->top(), thread, gc_state_offset);
886 Node* gc_state = new LoadBNode(old_ctrl, raw_mem, gc_state_addr,
887 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(nullptr),
888 TypeInt::BYTE, MemNode::unordered);
889 Node* gc_state_and = new AndINode(gc_state, igvn.intcon(flags));
890 Node* gc_state_cmp = new CmpINode(gc_state_and, igvn.zerocon(T_INT));
891 Node* gc_state_bool = new BoolNode(gc_state_cmp, BoolTest::ne);
892
893 IfNode* gc_state_iff = new IfNode(old_ctrl, gc_state_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
894 ctrl = new IfTrueNode(gc_state_iff);
895 test_fail_ctrl = new IfFalseNode(gc_state_iff);
896
897 IdealLoopTree* loop = phase->get_loop(old_ctrl);
898 phase->register_control(gc_state_iff, loop, old_ctrl);
899 phase->register_control(ctrl, loop, gc_state_iff);
900 phase->register_control(test_fail_ctrl, loop, gc_state_iff);
901
902 phase->register_new_node(thread, old_ctrl);
903 phase->register_new_node(gc_state_addr, old_ctrl);
904 phase->register_new_node(gc_state, old_ctrl);
905 phase->register_new_node(gc_state_and, old_ctrl);
906 phase->register_new_node(gc_state_cmp, old_ctrl);
907 phase->register_new_node(gc_state_bool, old_ctrl);
908
909 phase->set_ctrl(gc_state_offset, phase->C->root());
910
911 assert(is_gc_state_test(gc_state_iff, flags), "Should match the shape");
912 }
913
914 void ShenandoahBarrierC2Support::test_null(Node*& ctrl, Node* val, Node*& null_ctrl, PhaseIdealLoop* phase) {
915 Node* old_ctrl = ctrl;
916 PhaseIterGVN& igvn = phase->igvn();
917
918 const Type* val_t = igvn.type(val);
919 if (val_t->meet(TypePtr::NULL_PTR) == val_t) {
920 Node* null_cmp = new CmpPNode(val, igvn.zerocon(T_OBJECT));
921 Node* null_test = new BoolNode(null_cmp, BoolTest::ne);
922
923 IfNode* null_iff = new IfNode(old_ctrl, null_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
924 ctrl = new IfTrueNode(null_iff);
925 null_ctrl = new IfFalseNode(null_iff);
926
927 IdealLoopTree* loop = phase->get_loop(old_ctrl);
928 phase->register_control(null_iff, loop, old_ctrl);
929 phase->register_control(ctrl, loop, null_iff);
930 phase->register_control(null_ctrl, loop, null_iff);
931
932 phase->register_new_node(null_cmp, old_ctrl);
933 phase->register_new_node(null_test, old_ctrl);
934 }
935 }
936
937 void ShenandoahBarrierC2Support::test_in_cset(Node*& ctrl, Node*& not_cset_ctrl, Node* val, Node* raw_mem, PhaseIdealLoop* phase) {
938 Node* old_ctrl = ctrl;
939 PhaseIterGVN& igvn = phase->igvn();
940
941 Node* raw_val = new CastP2XNode(old_ctrl, val);
942 Node* cset_idx = new URShiftXNode(raw_val, igvn.intcon(ShenandoahHeapRegion::region_size_bytes_shift_jint()));
943
944 // Figure out the target cset address with raw pointer math.
945 // This avoids matching AddP+LoadB that would emit inefficient code.
946 // See JDK-8245465.
947 Node* cset_addr_ptr = igvn.makecon(TypeRawPtr::make(ShenandoahHeap::in_cset_fast_test_addr()));
948 Node* cset_addr = new CastP2XNode(old_ctrl, cset_addr_ptr);
949 Node* cset_load_addr = new AddXNode(cset_addr, cset_idx);
950 Node* cset_load_ptr = new CastX2PNode(cset_load_addr);
951
952 Node* cset_load = new LoadBNode(old_ctrl, raw_mem, cset_load_ptr,
953 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(nullptr),
954 TypeInt::BYTE, MemNode::unordered);
955 Node* cset_cmp = new CmpINode(cset_load, igvn.zerocon(T_INT));
956 Node* cset_bool = new BoolNode(cset_cmp, BoolTest::ne);
957
958 IfNode* cset_iff = new IfNode(old_ctrl, cset_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
959 ctrl = new IfTrueNode(cset_iff);
960 not_cset_ctrl = new IfFalseNode(cset_iff);
961
962 IdealLoopTree *loop = phase->get_loop(old_ctrl);
963 phase->register_control(cset_iff, loop, old_ctrl);
964 phase->register_control(ctrl, loop, cset_iff);
965 phase->register_control(not_cset_ctrl, loop, cset_iff);
966
967 phase->set_ctrl(cset_addr_ptr, phase->C->root());
968
969 phase->register_new_node(raw_val, old_ctrl);
970 phase->register_new_node(cset_idx, old_ctrl);
971 phase->register_new_node(cset_addr, old_ctrl);
972 phase->register_new_node(cset_load_addr, old_ctrl);
973 phase->register_new_node(cset_load_ptr, old_ctrl);
974 phase->register_new_node(cset_load, old_ctrl);
975 phase->register_new_node(cset_cmp, old_ctrl);
976 phase->register_new_node(cset_bool, old_ctrl);
977 }
978
979 void ShenandoahBarrierC2Support::call_lrb_stub(Node*& ctrl, Node*& val, Node* load_addr,
980 DecoratorSet decorators, PhaseIdealLoop* phase) {
981 IdealLoopTree*loop = phase->get_loop(ctrl);
982 const TypePtr* obj_type = phase->igvn().type(val)->is_oopptr();
983
984 address calladdr = nullptr;
985 const char* name = nullptr;
986 bool is_strong = ShenandoahBarrierSet::is_strong_access(decorators);
987 bool is_weak = ShenandoahBarrierSet::is_weak_access(decorators);
988 bool is_phantom = ShenandoahBarrierSet::is_phantom_access(decorators);
989 bool is_native = ShenandoahBarrierSet::is_native_access(decorators);
990 bool is_narrow = UseCompressedOops && !is_native;
991 if (is_strong) {
992 if (is_narrow) {
993 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong_narrow);
994 name = "load_reference_barrier_strong_narrow";
995 } else {
996 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong);
997 name = "load_reference_barrier_strong";
998 }
999 } else if (is_weak) {
1000 if (is_narrow) {
1001 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak_narrow);
1002 name = "load_reference_barrier_weak_narrow";
1003 } else {
1004 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak);
1005 name = "load_reference_barrier_weak";
1006 }
1007 } else {
1008 assert(is_phantom, "only remaining strength");
1009 if (is_narrow) {
1010 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom_narrow);
1011 name = "load_reference_barrier_phantom_narrow";
1012 } else {
1013 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom);
1014 name = "load_reference_barrier_phantom";
1015 }
1016 }
1017 Node* call = new CallLeafNode(ShenandoahBarrierSetC2::shenandoah_load_reference_barrier_Type(), calladdr, name, TypeRawPtr::BOTTOM);
1018
1019 call->init_req(TypeFunc::Control, ctrl);
1020 call->init_req(TypeFunc::I_O, phase->C->top());
1021 call->init_req(TypeFunc::Memory, phase->C->top());
1022 call->init_req(TypeFunc::FramePtr, phase->C->top());
1023 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
1024 call->init_req(TypeFunc::Parms, val);
1025 call->init_req(TypeFunc::Parms+1, load_addr);
1026 phase->register_control(call, loop, ctrl);
1027 ctrl = new ProjNode(call, TypeFunc::Control);
1028 phase->register_control(ctrl, loop, call);
1029 val = new ProjNode(call, TypeFunc::Parms);
1030 phase->register_new_node(val, call);
1031 val = new CheckCastPPNode(ctrl, val, obj_type);
1032 phase->register_new_node(val, ctrl);
1033 }
1034
1035 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) {
1036 Node* ctrl = phase->get_ctrl(barrier);
1037 Node* init_raw_mem = fixer.find_mem(ctrl, barrier);
1038
1039 // Update the control of all nodes that should be after the
1040 // barrier control flow
1041 uses.clear();
1042 // Every node that is control dependent on the barrier's input
1043 // control will be after the expanded barrier. The raw memory (if
1044 // its memory is control dependent on the barrier's input control)
1045 // must stay above the barrier.
1046 uses_to_ignore.clear();
1047 if (phase->has_ctrl(init_raw_mem) && phase->get_ctrl(init_raw_mem) == ctrl && !init_raw_mem->is_Phi()) {
1048 uses_to_ignore.push(init_raw_mem);
1049 }
1050 for (uint next = 0; next < uses_to_ignore.size(); next++) {
1051 Node *n = uses_to_ignore.at(next);
1052 for (uint i = 0; i < n->req(); i++) {
1053 Node* in = n->in(i);
1054 if (in != nullptr && phase->has_ctrl(in) && phase->get_ctrl(in) == ctrl) {
1055 uses_to_ignore.push(in);
1056 }
1057 }
1058 }
1059 for (DUIterator_Fast imax, i = ctrl->fast_outs(imax); i < imax; i++) {
1060 Node* u = ctrl->fast_out(i);
1061 if (u->_idx < last &&
1062 u != barrier &&
1063 !uses_to_ignore.member(u) &&
1064 (u->in(0) != ctrl || (!u->is_Region() && !u->is_Phi())) &&
1065 (ctrl->Opcode() != Op_CatchProj || u->Opcode() != Op_CreateEx)) {
1066 Node* old_c = phase->ctrl_or_self(u);
1067 Node* c = old_c;
1068 if (c != ctrl ||
1069 is_dominator_same_ctrl(old_c, barrier, u, phase) ||
1070 ShenandoahBarrierSetC2::is_shenandoah_state_load(u)) {
1071 phase->igvn().rehash_node_delayed(u);
1072 int nb = u->replace_edge(ctrl, region, &phase->igvn());
1073 if (u->is_CFG()) {
1074 if (phase->idom(u) == ctrl) {
1075 phase->set_idom(u, region, phase->dom_depth(region));
1076 }
1077 } else if (phase->get_ctrl(u) == ctrl) {
1078 assert(u != init_raw_mem, "should leave input raw mem above the barrier");
1079 uses.push(u);
1080 }
1081 assert(nb == 1, "more than 1 ctrl input?");
1082 --i, imax -= nb;
1083 }
1084 }
1085 }
1086 }
1087
1088 static Node* create_phis_on_call_return(Node* ctrl, Node* c, Node* n, Node* n_clone, const CallProjections& projs, PhaseIdealLoop* phase) {
1089 Node* region = nullptr;
1090 while (c != ctrl) {
1091 if (c->is_Region()) {
1092 region = c;
1093 }
1094 c = phase->idom(c);
1095 }
1096 assert(region != nullptr, "");
1097 Node* phi = new PhiNode(region, n->bottom_type());
1098 for (uint j = 1; j < region->req(); j++) {
1099 Node* in = region->in(j);
1100 if (phase->is_dominator(projs.fallthrough_catchproj, in)) {
1101 phi->init_req(j, n);
1102 } else if (phase->is_dominator(projs.catchall_catchproj, in)) {
1103 phi->init_req(j, n_clone);
1104 } else {
1105 phi->init_req(j, create_phis_on_call_return(ctrl, in, n, n_clone, projs, phase));
1106 }
1107 }
1108 phase->register_new_node(phi, region);
1109 return phi;
1110 }
1111
1112 void ShenandoahBarrierC2Support::pin_and_expand(PhaseIdealLoop* phase) {
1113 ShenandoahBarrierSetC2State* state = ShenandoahBarrierSetC2::bsc2()->state();
1114
1115 Unique_Node_List uses;
1116 for (int i = 0; i < state->iu_barriers_count(); i++) {
1117 Node* barrier = state->iu_barrier(i);
1118 Node* ctrl = phase->get_ctrl(barrier);
1119 IdealLoopTree* loop = phase->get_loop(ctrl);
1120 Node* head = loop->head();
1121 if (head->is_OuterStripMinedLoop()) {
1122 // Expanding a barrier here will break loop strip mining
1123 // verification. Transform the loop so the loop nest doesn't
1124 // appear as strip mined.
1125 OuterStripMinedLoopNode* outer = head->as_OuterStripMinedLoop();
1126 hide_strip_mined_loop(outer, outer->unique_ctrl_out()->as_CountedLoop(), phase);
1127 }
1128 }
1129
1130 Node_Stack stack(0);
1131 Node_List clones;
1132 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1133 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1134
1135 Node* ctrl = phase->get_ctrl(lrb);
1136 Node* val = lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
1137
1138 CallStaticJavaNode* unc = nullptr;
1139 Node* unc_ctrl = nullptr;
1140 Node* uncasted_val = val;
1141
1142 for (DUIterator_Fast imax, i = lrb->fast_outs(imax); i < imax; i++) {
1143 Node* u = lrb->fast_out(i);
1144 if (u->Opcode() == Op_CastPP &&
1145 u->in(0) != nullptr &&
1146 phase->is_dominator(u->in(0), ctrl)) {
1147 const Type* u_t = phase->igvn().type(u);
1148
1149 if (u_t->meet(TypePtr::NULL_PTR) != u_t &&
1150 u->in(0)->Opcode() == Op_IfTrue &&
1151 u->in(0)->as_Proj()->is_uncommon_trap_if_pattern() &&
1152 u->in(0)->in(0)->is_If() &&
1153 u->in(0)->in(0)->in(1)->Opcode() == Op_Bool &&
1154 u->in(0)->in(0)->in(1)->as_Bool()->_test._test == BoolTest::ne &&
1155 u->in(0)->in(0)->in(1)->in(1)->Opcode() == Op_CmpP &&
1156 u->in(0)->in(0)->in(1)->in(1)->in(1) == val &&
1157 u->in(0)->in(0)->in(1)->in(1)->in(2)->bottom_type() == TypePtr::NULL_PTR) {
1158 IdealLoopTree* loop = phase->get_loop(ctrl);
1159 IdealLoopTree* unc_loop = phase->get_loop(u->in(0));
1160
1161 if (!unc_loop->is_member(loop)) {
1162 continue;
1163 }
1164
1165 Node* branch = no_branches(ctrl, u->in(0), false, phase);
1166 assert(branch == nullptr || branch == NodeSentinel, "was not looking for a branch");
1167 if (branch == NodeSentinel) {
1168 continue;
1169 }
1170
1171 Node* iff = u->in(0)->in(0);
1172 Node* bol = iff->in(1)->clone();
1173 Node* cmp = bol->in(1)->clone();
1174 cmp->set_req(1, lrb);
1175 bol->set_req(1, cmp);
1176 phase->igvn().replace_input_of(iff, 1, bol);
1177 phase->set_ctrl(lrb, iff->in(0));
1178 phase->register_new_node(cmp, iff->in(0));
1179 phase->register_new_node(bol, iff->in(0));
1180 break;
1181 }
1182 }
1183 }
1184 if ((ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) || ctrl->is_CallJava()) {
1185 CallNode* call = ctrl->is_Proj() ? ctrl->in(0)->as_CallJava() : ctrl->as_CallJava();
1186 if (call->entry_point() == OptoRuntime::rethrow_stub()) {
1187 // The rethrow call may have too many projections to be
1188 // properly handled here. Given there's no reason for a
1189 // barrier to depend on the call, move it above the call
1190 stack.push(lrb, 0);
1191 do {
1192 Node* n = stack.node();
1193 uint idx = stack.index();
1194 if (idx < n->req()) {
1195 Node* in = n->in(idx);
1196 stack.set_index(idx+1);
1197 if (in != nullptr) {
1198 if (phase->has_ctrl(in)) {
1199 if (phase->is_dominator(call, phase->get_ctrl(in))) {
1200 #ifdef ASSERT
1201 for (uint i = 0; i < stack.size(); i++) {
1202 assert(stack.node_at(i) != in, "node shouldn't have been seen yet");
1203 }
1204 #endif
1205 stack.push(in, 0);
1206 }
1207 } else {
1208 assert(phase->is_dominator(in, call->in(0)), "no dependency on the call");
1209 }
1210 }
1211 } else {
1212 phase->set_ctrl(n, call->in(0));
1213 stack.pop();
1214 }
1215 } while(stack.size() > 0);
1216 continue;
1217 }
1218 CallProjections projs;
1219 call->extract_projections(&projs, false, false);
1220
1221 #ifdef ASSERT
1222 VectorSet cloned;
1223 #endif
1224 Node* lrb_clone = lrb->clone();
1225 phase->register_new_node(lrb_clone, projs.catchall_catchproj);
1226 phase->set_ctrl(lrb, projs.fallthrough_catchproj);
1227
1228 stack.push(lrb, 0);
1229 clones.push(lrb_clone);
1230
1231 do {
1232 assert(stack.size() == clones.size(), "");
1233 Node* n = stack.node();
1234 #ifdef ASSERT
1235 if (n->is_Load()) {
1236 Node* mem = n->in(MemNode::Memory);
1237 for (DUIterator_Fast jmax, j = mem->fast_outs(jmax); j < jmax; j++) {
1238 Node* u = mem->fast_out(j);
1239 assert(!u->is_Store() || !u->is_LoadStore() || phase->get_ctrl(u) != ctrl, "anti dependent store?");
1240 }
1241 }
1242 #endif
1243 uint idx = stack.index();
1244 Node* n_clone = clones.at(clones.size()-1);
1245 if (idx < n->outcnt()) {
1246 Node* u = n->raw_out(idx);
1247 Node* c = phase->ctrl_or_self(u);
1248 if (phase->is_dominator(call, c) && phase->is_dominator(c, projs.fallthrough_proj)) {
1249 stack.set_index(idx+1);
1250 assert(!u->is_CFG(), "");
1251 stack.push(u, 0);
1252 assert(!cloned.test_set(u->_idx), "only one clone");
1253 Node* u_clone = u->clone();
1254 int nb = u_clone->replace_edge(n, n_clone, &phase->igvn());
1255 assert(nb > 0, "should have replaced some uses");
1256 phase->register_new_node(u_clone, projs.catchall_catchproj);
1257 clones.push(u_clone);
1258 phase->set_ctrl(u, projs.fallthrough_catchproj);
1259 } else {
1260 bool replaced = false;
1261 if (u->is_Phi()) {
1262 for (uint k = 1; k < u->req(); k++) {
1263 if (u->in(k) == n) {
1264 if (phase->is_dominator(projs.catchall_catchproj, u->in(0)->in(k))) {
1265 phase->igvn().replace_input_of(u, k, n_clone);
1266 replaced = true;
1267 } else if (!phase->is_dominator(projs.fallthrough_catchproj, u->in(0)->in(k))) {
1268 phase->igvn().replace_input_of(u, k, create_phis_on_call_return(ctrl, u->in(0)->in(k), n, n_clone, projs, phase));
1269 replaced = true;
1270 }
1271 }
1272 }
1273 } else {
1274 if (phase->is_dominator(projs.catchall_catchproj, c)) {
1275 phase->igvn().rehash_node_delayed(u);
1276 int nb = u->replace_edge(n, n_clone, &phase->igvn());
1277 assert(nb > 0, "should have replaced some uses");
1278 replaced = true;
1279 } else if (!phase->is_dominator(projs.fallthrough_catchproj, c)) {
1280 if (u->is_If()) {
1281 // Can't break If/Bool/Cmp chain
1282 assert(n->is_Bool(), "unexpected If shape");
1283 assert(stack.node_at(stack.size()-2)->is_Cmp(), "unexpected If shape");
1284 assert(n_clone->is_Bool(), "unexpected clone");
1285 assert(clones.at(clones.size()-2)->is_Cmp(), "unexpected clone");
1286 Node* bol_clone = n->clone();
1287 Node* cmp_clone = stack.node_at(stack.size()-2)->clone();
1288 bol_clone->set_req(1, cmp_clone);
1289
1290 Node* nn = stack.node_at(stack.size()-3);
1291 Node* nn_clone = clones.at(clones.size()-3);
1292 assert(nn->Opcode() == nn_clone->Opcode(), "mismatch");
1293
1294 int nb = cmp_clone->replace_edge(nn, create_phis_on_call_return(ctrl, c, nn, nn_clone, projs, phase),
1295 &phase->igvn());
1296 assert(nb > 0, "should have replaced some uses");
1297
1298 phase->register_new_node(bol_clone, u->in(0));
1299 phase->register_new_node(cmp_clone, u->in(0));
1300
1301 phase->igvn().replace_input_of(u, 1, bol_clone);
1302
1303 } else {
1304 phase->igvn().rehash_node_delayed(u);
1305 int nb = u->replace_edge(n, create_phis_on_call_return(ctrl, c, n, n_clone, projs, phase), &phase->igvn());
1306 assert(nb > 0, "should have replaced some uses");
1307 }
1308 replaced = true;
1309 }
1310 }
1311 if (!replaced) {
1312 stack.set_index(idx+1);
1313 }
1314 }
1315 } else {
1316 stack.pop();
1317 clones.pop();
1318 }
1319 } while (stack.size() > 0);
1320 assert(stack.size() == 0 && clones.size() == 0, "");
1321 }
1322 }
1323
1324 for (int i = 0; i < state->load_reference_barriers_count(); i++) {
1325 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1326 Node* ctrl = phase->get_ctrl(lrb);
1327 IdealLoopTree* loop = phase->get_loop(ctrl);
1328 Node* head = loop->head();
1329 if (head->is_OuterStripMinedLoop()) {
1330 // Expanding a barrier here will break loop strip mining
1331 // verification. Transform the loop so the loop nest doesn't
1332 // appear as strip mined.
1333 OuterStripMinedLoopNode* outer = head->as_OuterStripMinedLoop();
1334 hide_strip_mined_loop(outer, outer->unique_ctrl_out()->as_CountedLoop(), phase);
1335 }
1336 if (head->is_BaseCountedLoop() && ctrl->is_IfProj() && ctrl->in(0)->is_BaseCountedLoopEnd() &&
1337 head->as_BaseCountedLoop()->loopexit() == ctrl->in(0)) {
1338 Node* entry = head->in(LoopNode::EntryControl);
1339 Node* backedge = head->in(LoopNode::LoopBackControl);
1340 Node* new_head = new LoopNode(entry, backedge);
1341 phase->register_control(new_head, phase->get_loop(entry), entry);
1342 phase->lazy_replace(head, new_head);
1343 }
1344 }
1345
1346 // Expand load-reference-barriers
1347 MemoryGraphFixer fixer(Compile::AliasIdxRaw, true, phase);
1348 Unique_Node_List uses_to_ignore;
1349 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1350 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1351 uint last = phase->C->unique();
1352 Node* ctrl = phase->get_ctrl(lrb);
1353 Node* val = lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
1354
1355 Node* orig_ctrl = ctrl;
1356
1357 Node* raw_mem = fixer.find_mem(ctrl, lrb);
1358 Node* raw_mem_for_ctrl = fixer.find_mem(ctrl, nullptr);
1359
1360 IdealLoopTree *loop = phase->get_loop(ctrl);
1361
1362 Node* heap_stable_ctrl = nullptr;
1363 Node* null_ctrl = nullptr;
1364
1365 assert(val->bottom_type()->make_oopptr(), "need oop");
1366 assert(val->bottom_type()->make_oopptr()->const_oop() == nullptr, "expect non-constant");
1367
1368 enum { _heap_stable = 1, _evac_path, _not_cset, PATH_LIMIT };
1369 Node* region = new RegionNode(PATH_LIMIT);
1370 Node* val_phi = new PhiNode(region, val->bottom_type()->is_oopptr());
1371
1372 // Stable path.
1373 int flags = ShenandoahHeap::HAS_FORWARDED;
1374 if (!ShenandoahBarrierSet::is_strong_access(lrb->decorators())) {
1375 flags |= ShenandoahHeap::WEAK_ROOTS;
1376 }
1377 test_gc_state(ctrl, raw_mem, heap_stable_ctrl, phase, flags);
1378 IfNode* heap_stable_iff = heap_stable_ctrl->in(0)->as_If();
1379
1380 // Heap stable case
1381 region->init_req(_heap_stable, heap_stable_ctrl);
1382 val_phi->init_req(_heap_stable, val);
1383
1384 // Test for in-cset, unless it's a native-LRB. Native LRBs need to return null
1385 // even for non-cset objects to prevent resurrection of such objects.
1386 // Wires !in_cset(obj) to slot 2 of region and phis
1387 Node* not_cset_ctrl = nullptr;
1388 if (ShenandoahBarrierSet::is_strong_access(lrb->decorators())) {
1389 test_in_cset(ctrl, not_cset_ctrl, val, raw_mem, phase);
1390 }
1391 if (not_cset_ctrl != nullptr) {
1392 region->init_req(_not_cset, not_cset_ctrl);
1393 val_phi->init_req(_not_cset, val);
1394 } else {
1395 region->del_req(_not_cset);
1396 val_phi->del_req(_not_cset);
1397 }
1398
1399 // Resolve object when orig-value is in cset.
1400 // Make the unconditional resolve for fwdptr.
1401
1402 // Call lrb-stub and wire up that path in slots 4
1403 Node* result_mem = nullptr;
1404
1405 Node* addr;
1406 {
1407 VectorSet visited;
1408 addr = get_load_addr(phase, visited, lrb);
1409 }
1410 if (addr->Opcode() == Op_AddP) {
1411 Node* orig_base = addr->in(AddPNode::Base);
1412 Node* base = new CheckCastPPNode(ctrl, orig_base, orig_base->bottom_type(), ConstraintCastNode::StrongDependency);
1413 phase->register_new_node(base, ctrl);
1414 if (addr->in(AddPNode::Base) == addr->in((AddPNode::Address))) {
1415 // Field access
1416 addr = addr->clone();
1417 addr->set_req(AddPNode::Base, base);
1418 addr->set_req(AddPNode::Address, base);
1419 phase->register_new_node(addr, ctrl);
1420 } else {
1421 Node* addr2 = addr->in(AddPNode::Address);
1422 if (addr2->Opcode() == Op_AddP && addr2->in(AddPNode::Base) == addr2->in(AddPNode::Address) &&
1423 addr2->in(AddPNode::Base) == orig_base) {
1424 addr2 = addr2->clone();
1425 addr2->set_req(AddPNode::Base, base);
1426 addr2->set_req(AddPNode::Address, base);
1427 phase->register_new_node(addr2, ctrl);
1428 addr = addr->clone();
1429 addr->set_req(AddPNode::Base, base);
1430 addr->set_req(AddPNode::Address, addr2);
1431 phase->register_new_node(addr, ctrl);
1432 }
1433 }
1434 }
1435 call_lrb_stub(ctrl, val, addr, lrb->decorators(), phase);
1436 region->init_req(_evac_path, ctrl);
1437 val_phi->init_req(_evac_path, val);
1438
1439 phase->register_control(region, loop, heap_stable_iff);
1440 Node* out_val = val_phi;
1441 phase->register_new_node(val_phi, region);
1442
1443 fix_ctrl(lrb, region, fixer, uses, uses_to_ignore, last, phase);
1444
1445 ctrl = orig_ctrl;
1446
1447 phase->igvn().replace_node(lrb, out_val);
1448
1449 follow_barrier_uses(out_val, ctrl, uses, phase);
1450
1451 for(uint next = 0; next < uses.size(); next++ ) {
1452 Node *n = uses.at(next);
1453 assert(phase->get_ctrl(n) == ctrl, "bad control");
1454 assert(n != raw_mem, "should leave input raw mem above the barrier");
1455 phase->set_ctrl(n, region);
1456 follow_barrier_uses(n, ctrl, uses, phase);
1457 }
1458 fixer.record_new_ctrl(ctrl, region, raw_mem, raw_mem_for_ctrl);
1459 }
1460 // Done expanding load-reference-barriers.
1461 assert(ShenandoahBarrierSetC2::bsc2()->state()->load_reference_barriers_count() == 0, "all load reference barrier nodes should have been replaced");
1462
1463 for (int i = state->iu_barriers_count() - 1; i >= 0; i--) {
1464 Node* barrier = state->iu_barrier(i);
1465 Node* pre_val = barrier->in(1);
1466
1467 if (phase->igvn().type(pre_val)->higher_equal(TypePtr::NULL_PTR)) {
1468 ShouldNotReachHere();
1469 continue;
1470 }
1471
1472 Node* ctrl = phase->get_ctrl(barrier);
1473
1474 if (ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) {
1475 assert(is_dominator(phase->get_ctrl(pre_val), ctrl->in(0)->in(0), pre_val, ctrl->in(0), phase), "can't move");
1476 ctrl = ctrl->in(0)->in(0);
1477 phase->set_ctrl(barrier, ctrl);
1478 } else if (ctrl->is_CallRuntime()) {
1479 assert(is_dominator(phase->get_ctrl(pre_val), ctrl->in(0), pre_val, ctrl, phase), "can't move");
1480 ctrl = ctrl->in(0);
1481 phase->set_ctrl(barrier, ctrl);
1482 }
1483
1484 Node* init_ctrl = ctrl;
1485 IdealLoopTree* loop = phase->get_loop(ctrl);
1486 Node* raw_mem = fixer.find_mem(ctrl, barrier);
1487 Node* init_raw_mem = raw_mem;
1488 Node* raw_mem_for_ctrl = fixer.find_mem(ctrl, nullptr);
1489 Node* heap_stable_ctrl = nullptr;
1490 Node* null_ctrl = nullptr;
1491 uint last = phase->C->unique();
1492
1493 enum { _heap_stable = 1, _heap_unstable, PATH_LIMIT };
1494 Node* region = new RegionNode(PATH_LIMIT);
1495 Node* phi = PhiNode::make(region, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
1496
1497 enum { _fast_path = 1, _slow_path, _null_path, PATH_LIMIT2 };
1498 Node* region2 = new RegionNode(PATH_LIMIT2);
1499 Node* phi2 = PhiNode::make(region2, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
1500
1501 // Stable path.
1502 test_gc_state(ctrl, raw_mem, heap_stable_ctrl, phase, ShenandoahHeap::MARKING);
1503 region->init_req(_heap_stable, heap_stable_ctrl);
1504 phi->init_req(_heap_stable, raw_mem);
1505
1506 // Null path
1507 Node* reg2_ctrl = nullptr;
1508 test_null(ctrl, pre_val, null_ctrl, phase);
1509 if (null_ctrl != nullptr) {
1510 reg2_ctrl = null_ctrl->in(0);
1511 region2->init_req(_null_path, null_ctrl);
1512 phi2->init_req(_null_path, raw_mem);
1513 } else {
1514 region2->del_req(_null_path);
1515 phi2->del_req(_null_path);
1516 }
1517
1518 const int index_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset());
1519 const int buffer_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset());
1520 Node* thread = new ThreadLocalNode();
1521 phase->register_new_node(thread, ctrl);
1522 Node* buffer_adr = new AddPNode(phase->C->top(), thread, phase->igvn().MakeConX(buffer_offset));
1523 phase->register_new_node(buffer_adr, ctrl);
1524 Node* index_adr = new AddPNode(phase->C->top(), thread, phase->igvn().MakeConX(index_offset));
1525 phase->register_new_node(index_adr, ctrl);
1526
1527 BasicType index_bt = TypeX_X->basic_type();
1528 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading Shenandoah SATBMarkQueue::_index with wrong size.");
1529 const TypePtr* adr_type = TypeRawPtr::BOTTOM;
1530 Node* index = new LoadXNode(ctrl, raw_mem, index_adr, adr_type, TypeX_X, MemNode::unordered);
1531 phase->register_new_node(index, ctrl);
1532 Node* index_cmp = new CmpXNode(index, phase->igvn().MakeConX(0));
1533 phase->register_new_node(index_cmp, ctrl);
1534 Node* index_test = new BoolNode(index_cmp, BoolTest::ne);
1535 phase->register_new_node(index_test, ctrl);
1536 IfNode* queue_full_iff = new IfNode(ctrl, index_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
1537 if (reg2_ctrl == nullptr) reg2_ctrl = queue_full_iff;
1538 phase->register_control(queue_full_iff, loop, ctrl);
1539 Node* not_full = new IfTrueNode(queue_full_iff);
1540 phase->register_control(not_full, loop, queue_full_iff);
1541 Node* full = new IfFalseNode(queue_full_iff);
1542 phase->register_control(full, loop, queue_full_iff);
1543
1544 ctrl = not_full;
1545
1546 Node* next_index = new SubXNode(index, phase->igvn().MakeConX(sizeof(intptr_t)));
1547 phase->register_new_node(next_index, ctrl);
1548
1549 Node* buffer = new LoadPNode(ctrl, raw_mem, buffer_adr, adr_type, TypeRawPtr::NOTNULL, MemNode::unordered);
1550 phase->register_new_node(buffer, ctrl);
1551 Node *log_addr = new AddPNode(phase->C->top(), buffer, next_index);
1552 phase->register_new_node(log_addr, ctrl);
1553 Node* log_store = new StorePNode(ctrl, raw_mem, log_addr, adr_type, pre_val, MemNode::unordered);
1554 phase->register_new_node(log_store, ctrl);
1555 // update the index
1556 Node* index_update = new StoreXNode(ctrl, log_store, index_adr, adr_type, next_index, MemNode::unordered);
1557 phase->register_new_node(index_update, ctrl);
1558
1559 // Fast-path case
1560 region2->init_req(_fast_path, ctrl);
1561 phi2->init_req(_fast_path, index_update);
1562
1563 ctrl = full;
1564
1565 Node* base = find_bottom_mem(ctrl, phase);
1566
1567 MergeMemNode* mm = MergeMemNode::make(base);
1568 mm->set_memory_at(Compile::AliasIdxRaw, raw_mem);
1569 phase->register_new_node(mm, ctrl);
1570
1571 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);
1572 call->init_req(TypeFunc::Control, ctrl);
1573 call->init_req(TypeFunc::I_O, phase->C->top());
1574 call->init_req(TypeFunc::Memory, mm);
1575 call->init_req(TypeFunc::FramePtr, phase->C->top());
1576 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
1577 call->init_req(TypeFunc::Parms, pre_val);
1578 call->init_req(TypeFunc::Parms+1, thread);
1579 phase->register_control(call, loop, ctrl);
1580
1581 Node* ctrl_proj = new ProjNode(call, TypeFunc::Control);
1582 phase->register_control(ctrl_proj, loop, call);
1583 Node* mem_proj = new ProjNode(call, TypeFunc::Memory);
1584 phase->register_new_node(mem_proj, call);
1585
1586 // Slow-path case
1587 region2->init_req(_slow_path, ctrl_proj);
1588 phi2->init_req(_slow_path, mem_proj);
1589
1590 phase->register_control(region2, loop, reg2_ctrl);
1591 phase->register_new_node(phi2, region2);
1592
1593 region->init_req(_heap_unstable, region2);
1594 phi->init_req(_heap_unstable, phi2);
1595
1596 phase->register_control(region, loop, heap_stable_ctrl->in(0));
1597 phase->register_new_node(phi, region);
1598
1599 fix_ctrl(barrier, region, fixer, uses, uses_to_ignore, last, phase);
1600 for(uint next = 0; next < uses.size(); next++ ) {
1601 Node *n = uses.at(next);
1602 assert(phase->get_ctrl(n) == init_ctrl, "bad control");
1603 assert(n != init_raw_mem, "should leave input raw mem above the barrier");
1604 phase->set_ctrl(n, region);
1605 follow_barrier_uses(n, init_ctrl, uses, phase);
1606 }
1607 fixer.fix_mem(init_ctrl, region, init_raw_mem, raw_mem_for_ctrl, phi, uses);
1608
1609 phase->igvn().replace_node(barrier, pre_val);
1610 }
1611 assert(state->iu_barriers_count() == 0, "all enqueue barrier nodes should have been replaced");
1612
1613 }
1614
1615 Node* ShenandoahBarrierC2Support::get_load_addr(PhaseIdealLoop* phase, VectorSet& visited, Node* in) {
1616 if (visited.test_set(in->_idx)) {
1617 return nullptr;
1618 }
1619 switch (in->Opcode()) {
1620 case Op_Proj:
1621 return get_load_addr(phase, visited, in->in(0));
1622 case Op_CastPP:
1623 case Op_CheckCastPP:
1624 case Op_DecodeN:
1625 case Op_EncodeP:
1626 return get_load_addr(phase, visited, in->in(1));
1627 case Op_LoadN:
1628 case Op_LoadP:
1629 return in->in(MemNode::Address);
1630 case Op_CompareAndExchangeN:
1631 case Op_CompareAndExchangeP:
1632 case Op_GetAndSetN:
1633 case Op_GetAndSetP:
1634 case Op_ShenandoahCompareAndExchangeP:
1635 case Op_ShenandoahCompareAndExchangeN:
1636 // Those instructions would just have stored a different
1637 // value into the field. No use to attempt to fix it at this point.
1638 return phase->igvn().zerocon(T_OBJECT);
1639 case Op_CMoveP:
1640 case Op_CMoveN: {
1641 Node* t = get_load_addr(phase, visited, in->in(CMoveNode::IfTrue));
1642 Node* f = get_load_addr(phase, visited, in->in(CMoveNode::IfFalse));
1643 // Handle unambiguous cases: single address reported on both branches.
1644 if (t != nullptr && f == nullptr) return t;
1645 if (t == nullptr && f != nullptr) return f;
1646 if (t != nullptr && t == f) return t;
1647 // Ambiguity.
1648 return phase->igvn().zerocon(T_OBJECT);
1649 }
1650 case Op_Phi: {
1651 Node* addr = nullptr;
1652 for (uint i = 1; i < in->req(); i++) {
1653 Node* addr1 = get_load_addr(phase, visited, in->in(i));
1654 if (addr == nullptr) {
1655 addr = addr1;
1656 }
1657 if (addr != addr1) {
1658 return phase->igvn().zerocon(T_OBJECT);
1659 }
1660 }
1661 return addr;
1662 }
1663 case Op_ShenandoahLoadReferenceBarrier:
1664 return get_load_addr(phase, visited, in->in(ShenandoahLoadReferenceBarrierNode::ValueIn));
1665 case Op_ShenandoahIUBarrier:
1666 return get_load_addr(phase, visited, in->in(1));
1667 case Op_CallDynamicJava:
1668 case Op_CallLeaf:
1669 case Op_CallStaticJava:
1670 case Op_ConN:
1671 case Op_ConP:
1672 case Op_Parm:
1673 case Op_CreateEx:
1674 return phase->igvn().zerocon(T_OBJECT);
1675 default:
1676 #ifdef ASSERT
1677 fatal("Unknown node in get_load_addr: %s", NodeClassNames[in->Opcode()]);
1678 #endif
1679 return phase->igvn().zerocon(T_OBJECT);
1680 }
1681
1682 }
1683
1684 void ShenandoahBarrierC2Support::move_gc_state_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase) {
1685 IdealLoopTree *loop = phase->get_loop(iff);
1686 Node* loop_head = loop->_head;
1687 Node* entry_c = loop_head->in(LoopNode::EntryControl);
1688
1689 Node* bol = iff->in(1);
1690 Node* cmp = bol->in(1);
1691 Node* andi = cmp->in(1);
1692 Node* load = andi->in(1);
1693
1694 assert(is_gc_state_load(load), "broken");
1695 if (!phase->is_dominator(load->in(0), entry_c)) {
1696 Node* mem_ctrl = nullptr;
1697 Node* mem = dom_mem(load->in(MemNode::Memory), loop_head, Compile::AliasIdxRaw, mem_ctrl, phase);
1698 load = load->clone();
1699 load->set_req(MemNode::Memory, mem);
1700 load->set_req(0, entry_c);
1701 phase->register_new_node(load, entry_c);
1702 andi = andi->clone();
1703 andi->set_req(1, load);
1704 phase->register_new_node(andi, entry_c);
1705 cmp = cmp->clone();
1706 cmp->set_req(1, andi);
1707 phase->register_new_node(cmp, entry_c);
1708 bol = bol->clone();
1709 bol->set_req(1, cmp);
1710 phase->register_new_node(bol, entry_c);
1711
1712 phase->igvn().replace_input_of(iff, 1, bol);
1713 }
1714 }
1715
1716 bool ShenandoahBarrierC2Support::identical_backtoback_ifs(Node* n, PhaseIdealLoop* phase) {
1717 if (!n->is_If() || n->is_CountedLoopEnd()) {
1718 return false;
1719 }
1720 Node* region = n->in(0);
1721
1722 if (!region->is_Region()) {
1723 return false;
1724 }
1725 Node* dom = phase->idom(region);
1726 if (!dom->is_If()) {
1727 return false;
1728 }
1729
1730 if (!is_heap_stable_test(n) || !is_heap_stable_test(dom)) {
1731 return false;
1732 }
1733
1734 IfNode* dom_if = dom->as_If();
1735 Node* proj_true = dom_if->proj_out(1);
1736 Node* proj_false = dom_if->proj_out(0);
1737
1738 for (uint i = 1; i < region->req(); i++) {
1739 if (phase->is_dominator(proj_true, region->in(i))) {
1740 continue;
1741 }
1742 if (phase->is_dominator(proj_false, region->in(i))) {
1743 continue;
1744 }
1745 return false;
1746 }
1747
1748 return true;
1749 }
1750
1751 bool ShenandoahBarrierC2Support::merge_point_safe(Node* region) {
1752 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
1753 Node* n = region->fast_out(i);
1754 if (n->is_LoadStore()) {
1755 // Splitting a LoadStore node through phi, causes it to lose its SCMemProj: the split if code doesn't have support
1756 // for a LoadStore at the region the if is split through because that's not expected to happen (LoadStore nodes
1757 // should be between barrier nodes). It does however happen with Shenandoah though because barriers can get
1758 // expanded around a LoadStore node.
1759 return false;
1760 }
1761 }
1762 return true;
1763 }
1764
1765
1766 void ShenandoahBarrierC2Support::merge_back_to_back_tests(Node* n, PhaseIdealLoop* phase) {
1767 assert(is_heap_stable_test(n), "no other tests");
1768 if (identical_backtoback_ifs(n, phase)) {
1769 Node* n_ctrl = n->in(0);
1770 if (phase->can_split_if(n_ctrl) && merge_point_safe(n_ctrl)) {
1771 IfNode* dom_if = phase->idom(n_ctrl)->as_If();
1772 if (is_heap_stable_test(n)) {
1773 Node* gc_state_load = n->in(1)->in(1)->in(1)->in(1);
1774 assert(is_gc_state_load(gc_state_load), "broken");
1775 Node* dom_gc_state_load = dom_if->in(1)->in(1)->in(1)->in(1);
1776 assert(is_gc_state_load(dom_gc_state_load), "broken");
1777 if (gc_state_load != dom_gc_state_load) {
1778 phase->igvn().replace_node(gc_state_load, dom_gc_state_load);
1779 }
1780 }
1781 PhiNode* bolphi = PhiNode::make_blank(n_ctrl, n->in(1));
1782 Node* proj_true = dom_if->proj_out(1);
1783 Node* proj_false = dom_if->proj_out(0);
1784 Node* con_true = phase->igvn().makecon(TypeInt::ONE);
1785 Node* con_false = phase->igvn().makecon(TypeInt::ZERO);
1786
1787 for (uint i = 1; i < n_ctrl->req(); i++) {
1788 if (phase->is_dominator(proj_true, n_ctrl->in(i))) {
1789 bolphi->init_req(i, con_true);
1790 } else {
1791 assert(phase->is_dominator(proj_false, n_ctrl->in(i)), "bad if");
1792 bolphi->init_req(i, con_false);
1793 }
1794 }
1795 phase->register_new_node(bolphi, n_ctrl);
1796 phase->igvn().replace_input_of(n, 1, bolphi);
1797 phase->do_split_if(n);
1798 }
1799 }
1800 }
1801
1802 IfNode* ShenandoahBarrierC2Support::find_unswitching_candidate(const IdealLoopTree* loop, PhaseIdealLoop* phase) {
1803 // Find first invariant test that doesn't exit the loop
1804 LoopNode *head = loop->_head->as_Loop();
1805 IfNode* unswitch_iff = nullptr;
1806 Node* n = head->in(LoopNode::LoopBackControl);
1807 int loop_has_sfpts = -1;
1808 while (n != head) {
1809 Node* n_dom = phase->idom(n);
1810 if (n->is_Region()) {
1811 if (n_dom->is_If()) {
1812 IfNode* iff = n_dom->as_If();
1813 if (iff->in(1)->is_Bool()) {
1814 BoolNode* bol = iff->in(1)->as_Bool();
1815 if (bol->in(1)->is_Cmp()) {
1816 // If condition is invariant and not a loop exit,
1817 // then found reason to unswitch.
1818 if (is_heap_stable_test(iff) &&
1819 (loop_has_sfpts == -1 || loop_has_sfpts == 0)) {
1820 assert(!loop->is_loop_exit(iff), "both branches should be in the loop");
1821 if (loop_has_sfpts == -1) {
1822 for(uint i = 0; i < loop->_body.size(); i++) {
1823 Node *m = loop->_body[i];
1824 if (m->is_SafePoint() && !m->is_CallLeaf()) {
1825 loop_has_sfpts = 1;
1826 break;
1827 }
1828 }
1829 if (loop_has_sfpts == -1) {
1830 loop_has_sfpts = 0;
1831 }
1832 }
1833 if (!loop_has_sfpts) {
1834 unswitch_iff = iff;
1835 }
1836 }
1837 }
1838 }
1839 }
1840 }
1841 n = n_dom;
1842 }
1843 return unswitch_iff;
1844 }
1845
1846
1847 void ShenandoahBarrierC2Support::optimize_after_expansion(VectorSet &visited, Node_Stack &stack, Node_List &old_new, PhaseIdealLoop* phase) {
1848 Node_List heap_stable_tests;
1849 stack.push(phase->C->start(), 0);
1850 do {
1851 Node* n = stack.node();
1852 uint i = stack.index();
1853
1854 if (i < n->outcnt()) {
1855 Node* u = n->raw_out(i);
1856 stack.set_index(i+1);
1857 if (!visited.test_set(u->_idx)) {
1858 stack.push(u, 0);
1859 }
1860 } else {
1861 stack.pop();
1862 if (n->is_If() && is_heap_stable_test(n)) {
1863 heap_stable_tests.push(n);
1864 }
1865 }
1866 } while (stack.size() > 0);
1867
1868 for (uint i = 0; i < heap_stable_tests.size(); i++) {
1869 Node* n = heap_stable_tests.at(i);
1870 assert(is_heap_stable_test(n), "only evacuation test");
1871 merge_back_to_back_tests(n, phase);
1872 }
1873
1874 if (!phase->C->major_progress()) {
1875 VectorSet seen;
1876 for (uint i = 0; i < heap_stable_tests.size(); i++) {
1877 Node* n = heap_stable_tests.at(i);
1878 IdealLoopTree* loop = phase->get_loop(n);
1879 if (loop != phase->ltree_root() &&
1880 loop->_child == nullptr &&
1881 !loop->_irreducible) {
1882 Node* head = loop->_head;
1883 if (head->is_Loop() &&
1884 (!head->is_CountedLoop() || head->as_CountedLoop()->is_main_loop() || head->as_CountedLoop()->is_normal_loop()) &&
1885 !seen.test_set(head->_idx)) {
1886 IfNode* iff = find_unswitching_candidate(loop, phase);
1887 if (iff != nullptr) {
1888 Node* bol = iff->in(1);
1889 if (head->as_Loop()->is_strip_mined()) {
1890 head->as_Loop()->verify_strip_mined(0);
1891 }
1892 move_gc_state_test_out_of_loop(iff, phase);
1893
1894 AutoNodeBudget node_budget(phase);
1895
1896 if (loop->policy_unswitching(phase)) {
1897 if (head->as_Loop()->is_strip_mined()) {
1898 OuterStripMinedLoopNode* outer = head->as_CountedLoop()->outer_loop();
1899 hide_strip_mined_loop(outer, head->as_CountedLoop(), phase);
1900 }
1901 phase->do_unswitching(loop, old_new);
1902 } else {
1903 // Not proceeding with unswitching. Move load back in
1904 // the loop.
1905 phase->igvn().replace_input_of(iff, 1, bol);
1906 }
1907 }
1908 }
1909 }
1910 }
1911 }
1912 }
1913
1914 ShenandoahIUBarrierNode::ShenandoahIUBarrierNode(Node* val) : Node(nullptr, val) {
1915 ShenandoahBarrierSetC2::bsc2()->state()->add_iu_barrier(this);
1916 }
1917
1918 const Type* ShenandoahIUBarrierNode::bottom_type() const {
1919 if (in(1) == nullptr || in(1)->is_top()) {
1920 return Type::TOP;
1921 }
1922 const Type* t = in(1)->bottom_type();
1923 if (t == TypePtr::NULL_PTR) {
1924 return t;
1925 }
1926 return t->is_oopptr();
1927 }
1928
1929 const Type* ShenandoahIUBarrierNode::Value(PhaseGVN* phase) const {
1930 if (in(1) == nullptr) {
1931 return Type::TOP;
1932 }
1933 const Type* t = phase->type(in(1));
1934 if (t == Type::TOP) {
1935 return Type::TOP;
1936 }
1937 if (t == TypePtr::NULL_PTR) {
1938 return t;
1939 }
1940 return t->is_oopptr();
1941 }
1942
1943 int ShenandoahIUBarrierNode::needed(Node* n) {
1944 if (n == nullptr ||
1945 n->is_Allocate() ||
1946 n->Opcode() == Op_ShenandoahIUBarrier ||
1947 n->bottom_type() == TypePtr::NULL_PTR ||
1948 (n->bottom_type()->make_oopptr() != nullptr && n->bottom_type()->make_oopptr()->const_oop() != nullptr)) {
1949 return NotNeeded;
1950 }
1951 if (n->is_Phi() ||
1952 n->is_CMove()) {
1953 return MaybeNeeded;
1954 }
1955 return Needed;
1956 }
1957
1958 Node* ShenandoahIUBarrierNode::next(Node* n) {
1959 for (;;) {
1960 if (n == nullptr) {
1961 return n;
1962 } else if (n->bottom_type() == TypePtr::NULL_PTR) {
1963 return n;
1964 } else if (n->bottom_type()->make_oopptr() != nullptr && n->bottom_type()->make_oopptr()->const_oop() != nullptr) {
1965 return n;
1966 } else if (n->is_ConstraintCast() ||
1967 n->Opcode() == Op_DecodeN ||
1968 n->Opcode() == Op_EncodeP) {
1969 n = n->in(1);
1970 } else if (n->is_Proj()) {
1971 n = n->in(0);
1972 } else {
1973 return n;
1974 }
1975 }
1976 ShouldNotReachHere();
1977 return nullptr;
1978 }
1979
1980 Node* ShenandoahIUBarrierNode::Identity(PhaseGVN* phase) {
1981 PhaseIterGVN* igvn = phase->is_IterGVN();
1982
1983 Node* n = next(in(1));
1984
1985 int cont = needed(n);
1986
1987 if (cont == NotNeeded) {
1988 return in(1);
1989 } else if (cont == MaybeNeeded) {
1990 if (igvn == nullptr) {
1991 phase->record_for_igvn(this);
1992 return this;
1993 } else {
1994 ResourceMark rm;
1995 Unique_Node_List wq;
1996 uint wq_i = 0;
1997
1998 for (;;) {
1999 if (n->is_Phi()) {
2000 for (uint i = 1; i < n->req(); i++) {
2001 Node* m = n->in(i);
2002 if (m != nullptr) {
2003 wq.push(m);
2004 }
2005 }
2006 } else {
2007 assert(n->is_CMove(), "nothing else here");
2008 Node* m = n->in(CMoveNode::IfFalse);
2009 wq.push(m);
2010 m = n->in(CMoveNode::IfTrue);
2011 wq.push(m);
2012 }
2013 Node* orig_n = nullptr;
2014 do {
2015 if (wq_i >= wq.size()) {
2016 return in(1);
2017 }
2018 n = wq.at(wq_i);
2019 wq_i++;
2020 orig_n = n;
2021 n = next(n);
2022 cont = needed(n);
2023 if (cont == Needed) {
2024 return this;
2025 }
2026 } while (cont != MaybeNeeded || (orig_n != n && wq.member(n)));
2027 }
2028 }
2029 }
2030
2031 return this;
2032 }
2033
2034 #ifdef ASSERT
2035 static bool has_never_branch(Node* root) {
2036 for (uint i = 1; i < root->req(); i++) {
2037 Node* in = root->in(i);
2038 if (in != nullptr && in->Opcode() == Op_Halt && in->in(0)->is_Proj() && in->in(0)->in(0)->is_NeverBranch()) {
2039 return true;
2040 }
2041 }
2042 return false;
2043 }
2044 #endif
2045
2046 void MemoryGraphFixer::collect_memory_nodes() {
2047 Node_Stack stack(0);
2048 VectorSet visited;
2049 Node_List regions;
2050
2051 // Walk the raw memory graph and create a mapping from CFG node to
2052 // memory node. Exclude phis for now.
2053 stack.push(_phase->C->root(), 1);
2054 do {
2055 Node* n = stack.node();
2056 int opc = n->Opcode();
2057 uint i = stack.index();
2058 if (i < n->req()) {
2059 Node* mem = nullptr;
2060 if (opc == Op_Root) {
2061 Node* in = n->in(i);
2062 int in_opc = in->Opcode();
2063 if (in_opc == Op_Return || in_opc == Op_Rethrow) {
2064 mem = in->in(TypeFunc::Memory);
2065 } else if (in_opc == Op_Halt) {
2066 if (in->in(0)->is_Region()) {
2067 Node* r = in->in(0);
2068 for (uint j = 1; j < r->req(); j++) {
2069 assert(!r->in(j)->is_NeverBranch(), "");
2070 }
2071 } else {
2072 Node* proj = in->in(0);
2073 assert(proj->is_Proj(), "");
2074 Node* in = proj->in(0);
2075 assert(in->is_CallStaticJava() || in->is_NeverBranch() || in->Opcode() == Op_Catch || proj->is_IfProj(), "");
2076 if (in->is_CallStaticJava()) {
2077 mem = in->in(TypeFunc::Memory);
2078 } else if (in->Opcode() == Op_Catch) {
2079 Node* call = in->in(0)->in(0);
2080 assert(call->is_Call(), "");
2081 mem = call->in(TypeFunc::Memory);
2082 } else if (in->is_NeverBranch()) {
2083 mem = collect_memory_for_infinite_loop(in);
2084 }
2085 }
2086 } else {
2087 #ifdef ASSERT
2088 n->dump();
2089 in->dump();
2090 #endif
2091 ShouldNotReachHere();
2092 }
2093 } else {
2094 assert(n->is_Phi() && n->bottom_type() == Type::MEMORY, "");
2095 assert(n->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(n->adr_type()) == _alias, "");
2096 mem = n->in(i);
2097 }
2098 i++;
2099 stack.set_index(i);
2100 if (mem == nullptr) {
2101 continue;
2102 }
2103 for (;;) {
2104 if (visited.test_set(mem->_idx) || mem->is_Start()) {
2105 break;
2106 }
2107 if (mem->is_Phi()) {
2108 stack.push(mem, 2);
2109 mem = mem->in(1);
2110 } else if (mem->is_Proj()) {
2111 stack.push(mem, mem->req());
2112 mem = mem->in(0);
2113 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
2114 mem = mem->in(TypeFunc::Memory);
2115 } else if (mem->is_MergeMem()) {
2116 MergeMemNode* mm = mem->as_MergeMem();
2117 mem = mm->memory_at(_alias);
2118 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
2119 assert(_alias == Compile::AliasIdxRaw, "");
2120 stack.push(mem, mem->req());
2121 mem = mem->in(MemNode::Memory);
2122 } else {
2123 #ifdef ASSERT
2124 mem->dump();
2125 #endif
2126 ShouldNotReachHere();
2127 }
2128 }
2129 } else {
2130 if (n->is_Phi()) {
2131 // Nothing
2132 } else if (!n->is_Root()) {
2133 Node* c = get_ctrl(n);
2134 _memory_nodes.map(c->_idx, n);
2135 }
2136 stack.pop();
2137 }
2138 } while(stack.is_nonempty());
2139
2140 // Iterate over CFG nodes in rpo and propagate memory state to
2141 // compute memory state at regions, creating new phis if needed.
2142 Node_List rpo_list;
2143 visited.clear();
2144 _phase->rpo(_phase->C->root(), stack, visited, rpo_list);
2145 Node* root = rpo_list.pop();
2146 assert(root == _phase->C->root(), "");
2147
2148 const bool trace = false;
2149 #ifdef ASSERT
2150 if (trace) {
2151 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2152 Node* c = rpo_list.at(i);
2153 if (_memory_nodes[c->_idx] != nullptr) {
2154 tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump();
2155 }
2156 }
2157 }
2158 #endif
2159 uint last = _phase->C->unique();
2160
2161 #ifdef ASSERT
2162 uint16_t max_depth = 0;
2163 for (LoopTreeIterator iter(_phase->ltree_root()); !iter.done(); iter.next()) {
2164 IdealLoopTree* lpt = iter.current();
2165 max_depth = MAX2(max_depth, lpt->_nest);
2166 }
2167 #endif
2168
2169 bool progress = true;
2170 int iteration = 0;
2171 Node_List dead_phis;
2172 while (progress) {
2173 progress = false;
2174 iteration++;
2175 assert(iteration <= 2+max_depth || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "");
2176 if (trace) { tty->print_cr("XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"); }
2177
2178 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2179 Node* c = rpo_list.at(i);
2180
2181 Node* prev_mem = _memory_nodes[c->_idx];
2182 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2183 Node* prev_region = regions[c->_idx];
2184 Node* unique = nullptr;
2185 for (uint j = 1; j < c->req() && unique != NodeSentinel; j++) {
2186 Node* m = _memory_nodes[c->in(j)->_idx];
2187 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");
2188 if (m != nullptr) {
2189 if (m == prev_region && ((c->is_Loop() && j == LoopNode::LoopBackControl) || (prev_region->is_Phi() && prev_region->in(0) == c))) {
2190 assert((c->is_Loop() && j == LoopNode::LoopBackControl) || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "");
2191 // continue
2192 } else if (unique == nullptr) {
2193 unique = m;
2194 } else if (m == unique) {
2195 // continue
2196 } else {
2197 unique = NodeSentinel;
2198 }
2199 }
2200 }
2201 assert(unique != nullptr, "empty phi???");
2202 if (unique != NodeSentinel) {
2203 if (prev_region != nullptr && prev_region->is_Phi() && prev_region->in(0) == c) {
2204 dead_phis.push(prev_region);
2205 }
2206 regions.map(c->_idx, unique);
2207 } else {
2208 Node* phi = nullptr;
2209 if (prev_region != nullptr && prev_region->is_Phi() && prev_region->in(0) == c && prev_region->_idx >= last) {
2210 phi = prev_region;
2211 for (uint k = 1; k < c->req(); k++) {
2212 Node* m = _memory_nodes[c->in(k)->_idx];
2213 assert(m != nullptr, "expect memory state");
2214 phi->set_req(k, m);
2215 }
2216 } else {
2217 for (DUIterator_Fast jmax, j = c->fast_outs(jmax); j < jmax && phi == nullptr; j++) {
2218 Node* u = c->fast_out(j);
2219 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2220 (u->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(u->adr_type()) == _alias)) {
2221 phi = u;
2222 for (uint k = 1; k < c->req() && phi != nullptr; k++) {
2223 Node* m = _memory_nodes[c->in(k)->_idx];
2224 assert(m != nullptr, "expect memory state");
2225 if (u->in(k) != m) {
2226 phi = NodeSentinel;
2227 }
2228 }
2229 }
2230 }
2231 if (phi == NodeSentinel) {
2232 phi = new PhiNode(c, Type::MEMORY, _phase->C->get_adr_type(_alias));
2233 for (uint k = 1; k < c->req(); k++) {
2234 Node* m = _memory_nodes[c->in(k)->_idx];
2235 assert(m != nullptr, "expect memory state");
2236 phi->init_req(k, m);
2237 }
2238 }
2239 }
2240 if (phi != nullptr) {
2241 regions.map(c->_idx, phi);
2242 } else {
2243 assert(c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
2244 }
2245 }
2246 Node* current_region = regions[c->_idx];
2247 if (current_region != prev_region) {
2248 progress = true;
2249 if (prev_region == prev_mem) {
2250 _memory_nodes.map(c->_idx, current_region);
2251 }
2252 }
2253 } else if (prev_mem == nullptr || prev_mem->is_Phi() || ctrl_or_self(prev_mem) != c) {
2254 Node* m = _memory_nodes[_phase->idom(c)->_idx];
2255 assert(m != nullptr || c->Opcode() == Op_Halt, "expect memory state");
2256 if (m != prev_mem) {
2257 _memory_nodes.map(c->_idx, m);
2258 progress = true;
2259 }
2260 }
2261 #ifdef ASSERT
2262 if (trace) { tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump(); }
2263 #endif
2264 }
2265 }
2266
2267 // Replace existing phi with computed memory state for that region
2268 // if different (could be a new phi or a dominating memory node if
2269 // that phi was found to be useless).
2270 while (dead_phis.size() > 0) {
2271 Node* n = dead_phis.pop();
2272 n->replace_by(_phase->C->top());
2273 n->destruct(&_phase->igvn());
2274 }
2275 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2276 Node* c = rpo_list.at(i);
2277 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2278 Node* n = regions[c->_idx];
2279 assert(n != nullptr || c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
2280 if (n != nullptr && n->is_Phi() && n->_idx >= last && n->in(0) == c) {
2281 _phase->register_new_node(n, c);
2282 }
2283 }
2284 }
2285 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2286 Node* c = rpo_list.at(i);
2287 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2288 Node* n = regions[c->_idx];
2289 assert(n != nullptr || c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
2290 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
2291 Node* u = c->fast_out(i);
2292 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2293 u != n) {
2294 assert(c->unique_ctrl_out()->Opcode() != Op_Halt, "expected memory state");
2295 if (u->adr_type() == TypePtr::BOTTOM) {
2296 fix_memory_uses(u, n, n, c);
2297 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2298 _phase->lazy_replace(u, n);
2299 --i; --imax;
2300 }
2301 }
2302 }
2303 }
2304 }
2305 }
2306
2307 Node* MemoryGraphFixer::collect_memory_for_infinite_loop(const Node* in) {
2308 Node* mem = nullptr;
2309 Node* head = in->in(0);
2310 assert(head->is_Region(), "unexpected infinite loop graph shape");
2311
2312 Node* phi_mem = nullptr;
2313 for (DUIterator_Fast jmax, j = head->fast_outs(jmax); j < jmax; j++) {
2314 Node* u = head->fast_out(j);
2315 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
2316 if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2317 assert(phi_mem == nullptr || phi_mem->adr_type() == TypePtr::BOTTOM, "");
2318 phi_mem = u;
2319 } else if (u->adr_type() == TypePtr::BOTTOM) {
2320 assert(phi_mem == nullptr || _phase->C->get_alias_index(phi_mem->adr_type()) == _alias, "");
2321 if (phi_mem == nullptr) {
2322 phi_mem = u;
2323 }
2324 }
2325 }
2326 }
2327 if (phi_mem == nullptr) {
2328 ResourceMark rm;
2329 Node_Stack stack(0);
2330 stack.push(head, 1);
2331 do {
2332 Node* n = stack.node();
2333 uint i = stack.index();
2334 if (i >= n->req()) {
2335 stack.pop();
2336 } else {
2337 stack.set_index(i + 1);
2338 Node* c = n->in(i);
2339 assert(c != head, "should have found a safepoint on the way");
2340 if (stack.size() != 1 || _phase->is_dominator(head, c)) {
2341 for (;;) {
2342 if (c->is_Region()) {
2343 stack.push(c, 1);
2344 break;
2345 } else if (c->is_SafePoint() && !c->is_CallLeaf()) {
2346 Node* m = c->in(TypeFunc::Memory);
2347 if (m->is_MergeMem()) {
2348 m = m->as_MergeMem()->memory_at(_alias);
2349 }
2350 assert(mem == nullptr || mem == m, "several memory states");
2351 mem = m;
2352 break;
2353 } else {
2354 assert(c != c->in(0), "");
2355 c = c->in(0);
2356 }
2357 }
2358 }
2359 }
2360 } while (stack.size() > 0);
2361 assert(mem != nullptr, "should have found safepoint");
2362 } else {
2363 mem = phi_mem;
2364 }
2365 return mem;
2366 }
2367
2368 Node* MemoryGraphFixer::get_ctrl(Node* n) const {
2369 Node* c = _phase->get_ctrl(n);
2370 if (n->is_Proj() && n->in(0) != nullptr && n->in(0)->is_Call()) {
2371 assert(c == n->in(0), "");
2372 CallNode* call = c->as_Call();
2373 CallProjections projs;
2374 call->extract_projections(&projs, true, false);
2375 if (projs.catchall_memproj != nullptr) {
2376 if (projs.fallthrough_memproj == n) {
2377 c = projs.fallthrough_catchproj;
2378 } else {
2379 assert(projs.catchall_memproj == n, "");
2380 c = projs.catchall_catchproj;
2381 }
2382 }
2383 }
2384 return c;
2385 }
2386
2387 Node* MemoryGraphFixer::ctrl_or_self(Node* n) const {
2388 if (_phase->has_ctrl(n))
2389 return get_ctrl(n);
2390 else {
2391 assert (n->is_CFG(), "must be a CFG node");
2392 return n;
2393 }
2394 }
2395
2396 bool MemoryGraphFixer::mem_is_valid(Node* m, Node* c) const {
2397 return m != nullptr && get_ctrl(m) == c;
2398 }
2399
2400 Node* MemoryGraphFixer::find_mem(Node* ctrl, Node* n) const {
2401 assert(n == nullptr || _phase->ctrl_or_self(n) == ctrl, "");
2402 assert(!ctrl->is_Call() || ctrl == n, "projection expected");
2403 #ifdef ASSERT
2404 if ((ctrl->is_Proj() && ctrl->in(0)->is_Call()) ||
2405 (ctrl->is_Catch() && ctrl->in(0)->in(0)->is_Call())) {
2406 CallNode* call = ctrl->is_Proj() ? ctrl->in(0)->as_Call() : ctrl->in(0)->in(0)->as_Call();
2407 int mems = 0;
2408 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) {
2409 Node* u = call->fast_out(i);
2410 if (u->bottom_type() == Type::MEMORY) {
2411 mems++;
2412 }
2413 }
2414 assert(mems <= 1, "No node right after call if multiple mem projections");
2415 }
2416 #endif
2417 Node* mem = _memory_nodes[ctrl->_idx];
2418 Node* c = ctrl;
2419 while (!mem_is_valid(mem, c) &&
2420 (!c->is_CatchProj() || mem == nullptr || c->in(0)->in(0)->in(0) != get_ctrl(mem))) {
2421 c = _phase->idom(c);
2422 mem = _memory_nodes[c->_idx];
2423 }
2424 if (n != nullptr && mem_is_valid(mem, c)) {
2425 while (!ShenandoahBarrierC2Support::is_dominator_same_ctrl(c, mem, n, _phase) && _phase->ctrl_or_self(mem) == ctrl) {
2426 mem = next_mem(mem, _alias);
2427 }
2428 if (mem->is_MergeMem()) {
2429 mem = mem->as_MergeMem()->memory_at(_alias);
2430 }
2431 if (!mem_is_valid(mem, c)) {
2432 do {
2433 c = _phase->idom(c);
2434 mem = _memory_nodes[c->_idx];
2435 } while (!mem_is_valid(mem, c) &&
2436 (!c->is_CatchProj() || mem == nullptr || c->in(0)->in(0)->in(0) != get_ctrl(mem)));
2437 }
2438 }
2439 assert(mem->bottom_type() == Type::MEMORY, "");
2440 return mem;
2441 }
2442
2443 bool MemoryGraphFixer::has_mem_phi(Node* region) const {
2444 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
2445 Node* use = region->fast_out(i);
2446 if (use->is_Phi() && use->bottom_type() == Type::MEMORY &&
2447 (_phase->C->get_alias_index(use->adr_type()) == _alias)) {
2448 return true;
2449 }
2450 }
2451 return false;
2452 }
2453
2454 void MemoryGraphFixer::fix_mem(Node* ctrl, Node* new_ctrl, Node* mem, Node* mem_for_ctrl, Node* new_mem, Unique_Node_List& uses) {
2455 assert(_phase->ctrl_or_self(new_mem) == new_ctrl, "");
2456 const bool trace = false;
2457 DEBUG_ONLY(if (trace) { tty->print("ZZZ control is"); ctrl->dump(); });
2458 DEBUG_ONLY(if (trace) { tty->print("ZZZ mem is"); mem->dump(); });
2459 GrowableArray<Node*> phis;
2460 if (mem_for_ctrl != mem) {
2461 Node* old = mem_for_ctrl;
2462 Node* prev = nullptr;
2463 while (old != mem) {
2464 prev = old;
2465 if (old->is_Store() || old->is_ClearArray() || old->is_LoadStore()) {
2466 assert(_alias == Compile::AliasIdxRaw, "");
2467 old = old->in(MemNode::Memory);
2468 } else if (old->Opcode() == Op_SCMemProj) {
2469 assert(_alias == Compile::AliasIdxRaw, "");
2470 old = old->in(0);
2471 } else {
2472 ShouldNotReachHere();
2473 }
2474 }
2475 assert(prev != nullptr, "");
2476 if (new_ctrl != ctrl) {
2477 _memory_nodes.map(ctrl->_idx, mem);
2478 _memory_nodes.map(new_ctrl->_idx, mem_for_ctrl);
2479 }
2480 uint input = (uint)MemNode::Memory;
2481 _phase->igvn().replace_input_of(prev, input, new_mem);
2482 } else {
2483 uses.clear();
2484 _memory_nodes.map(new_ctrl->_idx, new_mem);
2485 uses.push(new_ctrl);
2486 for(uint next = 0; next < uses.size(); next++ ) {
2487 Node *n = uses.at(next);
2488 assert(n->is_CFG(), "");
2489 DEBUG_ONLY(if (trace) { tty->print("ZZZ ctrl"); n->dump(); });
2490 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2491 Node* u = n->fast_out(i);
2492 if (!u->is_Root() && u->is_CFG() && u != n) {
2493 Node* m = _memory_nodes[u->_idx];
2494 if (u->is_Region() && (!u->is_OuterStripMinedLoop() || _include_lsm) &&
2495 !has_mem_phi(u) &&
2496 u->unique_ctrl_out()->Opcode() != Op_Halt) {
2497 DEBUG_ONLY(if (trace) { tty->print("ZZZ region"); u->dump(); });
2498 DEBUG_ONLY(if (trace && m != nullptr) { tty->print("ZZZ mem"); m->dump(); });
2499
2500 if (!mem_is_valid(m, u) || !m->is_Phi()) {
2501 bool push = true;
2502 bool create_phi = true;
2503 if (_phase->is_dominator(new_ctrl, u)) {
2504 create_phi = false;
2505 }
2506 if (create_phi) {
2507 Node* phi = new PhiNode(u, Type::MEMORY, _phase->C->get_adr_type(_alias));
2508 _phase->register_new_node(phi, u);
2509 phis.push(phi);
2510 DEBUG_ONLY(if (trace) { tty->print("ZZZ new phi"); phi->dump(); });
2511 if (!mem_is_valid(m, u)) {
2512 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting mem"); phi->dump(); });
2513 _memory_nodes.map(u->_idx, phi);
2514 } else {
2515 DEBUG_ONLY(if (trace) { tty->print("ZZZ NOT setting mem"); m->dump(); });
2516 for (;;) {
2517 assert(m->is_Mem() || m->is_LoadStore() || m->is_Proj(), "");
2518 Node* next = nullptr;
2519 if (m->is_Proj()) {
2520 next = m->in(0);
2521 } else {
2522 assert(m->is_Mem() || m->is_LoadStore(), "");
2523 assert(_alias == Compile::AliasIdxRaw, "");
2524 next = m->in(MemNode::Memory);
2525 }
2526 if (_phase->get_ctrl(next) != u) {
2527 break;
2528 }
2529 if (next->is_MergeMem()) {
2530 assert(_phase->get_ctrl(next->as_MergeMem()->memory_at(_alias)) != u, "");
2531 break;
2532 }
2533 if (next->is_Phi()) {
2534 assert(next->adr_type() == TypePtr::BOTTOM && next->in(0) == u, "");
2535 break;
2536 }
2537 m = next;
2538 }
2539
2540 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting to phi"); m->dump(); });
2541 assert(m->is_Mem() || m->is_LoadStore(), "");
2542 uint input = (uint)MemNode::Memory;
2543 _phase->igvn().replace_input_of(m, input, phi);
2544 push = false;
2545 }
2546 } else {
2547 DEBUG_ONLY(if (trace) { tty->print("ZZZ skipping region"); u->dump(); });
2548 }
2549 if (push) {
2550 uses.push(u);
2551 }
2552 }
2553 } else if (!mem_is_valid(m, u) &&
2554 !(u->Opcode() == Op_CProj && u->in(0)->is_NeverBranch() && u->as_Proj()->_con == 1)) {
2555 uses.push(u);
2556 }
2557 }
2558 }
2559 }
2560 for (int i = 0; i < phis.length(); i++) {
2561 Node* n = phis.at(i);
2562 Node* r = n->in(0);
2563 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi"); n->dump(); });
2564 for (uint j = 1; j < n->req(); j++) {
2565 Node* m = find_mem(r->in(j), nullptr);
2566 _phase->igvn().replace_input_of(n, j, m);
2567 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi: %d", j); m->dump(); });
2568 }
2569 }
2570 }
2571 uint last = _phase->C->unique();
2572 MergeMemNode* mm = nullptr;
2573 int alias = _alias;
2574 DEBUG_ONLY(if (trace) { tty->print("ZZZ raw mem is"); mem->dump(); });
2575 // Process loads first to not miss an anti-dependency: if the memory
2576 // edge of a store is updated before a load is processed then an
2577 // anti-dependency may be missed.
2578 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2579 Node* u = mem->out(i);
2580 if (u->_idx < last && u->is_Load() && _phase->C->get_alias_index(u->adr_type()) == alias) {
2581 Node* m = find_mem(_phase->get_ctrl(u), u);
2582 if (m != mem) {
2583 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2584 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2585 --i;
2586 }
2587 }
2588 }
2589 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2590 Node* u = mem->out(i);
2591 if (u->_idx < last) {
2592 if (u->is_Mem()) {
2593 if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2594 Node* m = find_mem(_phase->get_ctrl(u), u);
2595 if (m != mem) {
2596 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2597 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2598 --i;
2599 }
2600 }
2601 } else if (u->is_MergeMem()) {
2602 MergeMemNode* u_mm = u->as_MergeMem();
2603 if (u_mm->memory_at(alias) == mem) {
2604 MergeMemNode* newmm = nullptr;
2605 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2606 Node* uu = u->fast_out(j);
2607 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2608 if (uu->is_Phi()) {
2609 assert(uu->adr_type() == TypePtr::BOTTOM, "");
2610 Node* region = uu->in(0);
2611 int nb = 0;
2612 for (uint k = 1; k < uu->req(); k++) {
2613 if (uu->in(k) == u) {
2614 Node* m = find_mem(region->in(k), nullptr);
2615 if (m != mem) {
2616 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", k); uu->dump(); });
2617 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2618 if (newmm != u) {
2619 _phase->igvn().replace_input_of(uu, k, newmm);
2620 nb++;
2621 --jmax;
2622 }
2623 }
2624 }
2625 }
2626 if (nb > 0) {
2627 --j;
2628 }
2629 } else {
2630 Node* m = find_mem(_phase->ctrl_or_self(uu), uu);
2631 if (m != mem) {
2632 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); uu->dump(); });
2633 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2634 if (newmm != u) {
2635 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2636 --j, --jmax;
2637 }
2638 }
2639 }
2640 }
2641 }
2642 } else if (u->is_Phi()) {
2643 assert(u->bottom_type() == Type::MEMORY, "what else?");
2644 if (_phase->C->get_alias_index(u->adr_type()) == alias || u->adr_type() == TypePtr::BOTTOM) {
2645 Node* region = u->in(0);
2646 bool replaced = false;
2647 for (uint j = 1; j < u->req(); j++) {
2648 if (u->in(j) == mem) {
2649 Node* m = find_mem(region->in(j), nullptr);
2650 Node* nnew = m;
2651 if (m != mem) {
2652 if (u->adr_type() == TypePtr::BOTTOM) {
2653 mm = allocate_merge_mem(mem, m, _phase->ctrl_or_self(m));
2654 nnew = mm;
2655 }
2656 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", j); u->dump(); });
2657 _phase->igvn().replace_input_of(u, j, nnew);
2658 replaced = true;
2659 }
2660 }
2661 }
2662 if (replaced) {
2663 --i;
2664 }
2665 }
2666 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2667 u->adr_type() == nullptr) {
2668 assert(u->adr_type() != nullptr ||
2669 u->Opcode() == Op_Rethrow ||
2670 u->Opcode() == Op_Return ||
2671 u->Opcode() == Op_SafePoint ||
2672 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2673 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2674 u->Opcode() == Op_CallLeaf, "");
2675 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2676 if (m != mem) {
2677 mm = allocate_merge_mem(mem, m, _phase->get_ctrl(m));
2678 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2679 --i;
2680 }
2681 } else if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2682 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2683 if (m != mem) {
2684 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2685 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2686 --i;
2687 }
2688 } else if (u->adr_type() != TypePtr::BOTTOM &&
2689 _memory_nodes[_phase->ctrl_or_self(u)->_idx] == u) {
2690 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2691 assert(m != mem, "");
2692 // u is on the wrong slice...
2693 assert(u->is_ClearArray(), "");
2694 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2695 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2696 --i;
2697 }
2698 }
2699 }
2700 #ifdef ASSERT
2701 assert(new_mem->outcnt() > 0, "");
2702 for (int i = 0; i < phis.length(); i++) {
2703 Node* n = phis.at(i);
2704 assert(n->outcnt() > 0, "new phi must have uses now");
2705 }
2706 #endif
2707 }
2708
2709 void MemoryGraphFixer::record_new_ctrl(Node* ctrl, Node* new_ctrl, Node* mem, Node* mem_for_ctrl) {
2710 if (mem_for_ctrl != mem && new_ctrl != ctrl) {
2711 _memory_nodes.map(ctrl->_idx, mem);
2712 _memory_nodes.map(new_ctrl->_idx, mem_for_ctrl);
2713 }
2714 }
2715
2716 MergeMemNode* MemoryGraphFixer::allocate_merge_mem(Node* mem, Node* rep_proj, Node* rep_ctrl) const {
2717 MergeMemNode* mm = MergeMemNode::make(mem);
2718 mm->set_memory_at(_alias, rep_proj);
2719 _phase->register_new_node(mm, rep_ctrl);
2720 return mm;
2721 }
2722
2723 MergeMemNode* MemoryGraphFixer::clone_merge_mem(Node* u, Node* mem, Node* rep_proj, Node* rep_ctrl, DUIterator& i) const {
2724 MergeMemNode* newmm = nullptr;
2725 MergeMemNode* u_mm = u->as_MergeMem();
2726 Node* c = _phase->get_ctrl(u);
2727 if (_phase->is_dominator(c, rep_ctrl)) {
2728 c = rep_ctrl;
2729 } else {
2730 assert(_phase->is_dominator(rep_ctrl, c), "one must dominate the other");
2731 }
2732 if (u->outcnt() == 1) {
2733 if (u->req() > (uint)_alias && u->in(_alias) == mem) {
2734 _phase->igvn().replace_input_of(u, _alias, rep_proj);
2735 --i;
2736 } else {
2737 _phase->igvn().rehash_node_delayed(u);
2738 u_mm->set_memory_at(_alias, rep_proj);
2739 }
2740 newmm = u_mm;
2741 _phase->set_ctrl_and_loop(u, c);
2742 } else {
2743 // can't simply clone u and then change one of its input because
2744 // it adds and then removes an edge which messes with the
2745 // DUIterator
2746 newmm = MergeMemNode::make(u_mm->base_memory());
2747 for (uint j = 0; j < u->req(); j++) {
2748 if (j < newmm->req()) {
2749 if (j == (uint)_alias) {
2750 newmm->set_req(j, rep_proj);
2751 } else if (newmm->in(j) != u->in(j)) {
2752 newmm->set_req(j, u->in(j));
2753 }
2754 } else if (j == (uint)_alias) {
2755 newmm->add_req(rep_proj);
2756 } else {
2757 newmm->add_req(u->in(j));
2758 }
2759 }
2760 if ((uint)_alias >= u->req()) {
2761 newmm->set_memory_at(_alias, rep_proj);
2762 }
2763 _phase->register_new_node(newmm, c);
2764 }
2765 return newmm;
2766 }
2767
2768 bool MemoryGraphFixer::should_process_phi(Node* phi) const {
2769 if (phi->adr_type() == TypePtr::BOTTOM) {
2770 Node* region = phi->in(0);
2771 for (DUIterator_Fast jmax, j = region->fast_outs(jmax); j < jmax; j++) {
2772 Node* uu = region->fast_out(j);
2773 if (uu->is_Phi() && uu != phi && uu->bottom_type() == Type::MEMORY && _phase->C->get_alias_index(uu->adr_type()) == _alias) {
2774 return false;
2775 }
2776 }
2777 return true;
2778 }
2779 return _phase->C->get_alias_index(phi->adr_type()) == _alias;
2780 }
2781
2782 void MemoryGraphFixer::fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl) const {
2783 uint last = _phase-> C->unique();
2784 MergeMemNode* mm = nullptr;
2785 assert(mem->bottom_type() == Type::MEMORY, "");
2786 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2787 Node* u = mem->out(i);
2788 if (u != replacement && u->_idx < last) {
2789 if (u->is_MergeMem()) {
2790 MergeMemNode* u_mm = u->as_MergeMem();
2791 if (u_mm->memory_at(_alias) == mem) {
2792 MergeMemNode* newmm = nullptr;
2793 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2794 Node* uu = u->fast_out(j);
2795 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2796 if (uu->is_Phi()) {
2797 if (should_process_phi(uu)) {
2798 Node* region = uu->in(0);
2799 int nb = 0;
2800 for (uint k = 1; k < uu->req(); k++) {
2801 if (uu->in(k) == u && _phase->is_dominator(rep_ctrl, region->in(k))) {
2802 if (newmm == nullptr) {
2803 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2804 }
2805 if (newmm != u) {
2806 _phase->igvn().replace_input_of(uu, k, newmm);
2807 nb++;
2808 --jmax;
2809 }
2810 }
2811 }
2812 if (nb > 0) {
2813 --j;
2814 }
2815 }
2816 } else {
2817 if (rep_ctrl != uu && ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(uu), replacement, uu, _phase)) {
2818 if (newmm == nullptr) {
2819 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2820 }
2821 if (newmm != u) {
2822 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2823 --j, --jmax;
2824 }
2825 }
2826 }
2827 }
2828 }
2829 } else if (u->is_Phi()) {
2830 assert(u->bottom_type() == Type::MEMORY, "what else?");
2831 Node* region = u->in(0);
2832 if (should_process_phi(u)) {
2833 bool replaced = false;
2834 for (uint j = 1; j < u->req(); j++) {
2835 if (u->in(j) == mem && _phase->is_dominator(rep_ctrl, region->in(j))) {
2836 Node* nnew = rep_proj;
2837 if (u->adr_type() == TypePtr::BOTTOM) {
2838 if (mm == nullptr) {
2839 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2840 }
2841 nnew = mm;
2842 }
2843 _phase->igvn().replace_input_of(u, j, nnew);
2844 replaced = true;
2845 }
2846 }
2847 if (replaced) {
2848 --i;
2849 }
2850
2851 }
2852 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2853 u->adr_type() == nullptr) {
2854 assert(u->adr_type() != nullptr ||
2855 u->Opcode() == Op_Rethrow ||
2856 u->Opcode() == Op_Return ||
2857 u->Opcode() == Op_SafePoint ||
2858 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2859 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2860 u->Opcode() == Op_CallLeaf, "%s", u->Name());
2861 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2862 if (mm == nullptr) {
2863 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2864 }
2865 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2866 --i;
2867 }
2868 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2869 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2870 _phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
2871 --i;
2872 }
2873 }
2874 }
2875 }
2876 }
2877
2878 ShenandoahLoadReferenceBarrierNode::ShenandoahLoadReferenceBarrierNode(Node* ctrl, Node* obj, DecoratorSet decorators)
2879 : Node(ctrl, obj), _decorators(decorators) {
2880 ShenandoahBarrierSetC2::bsc2()->state()->add_load_reference_barrier(this);
2881 }
2882
2883 DecoratorSet ShenandoahLoadReferenceBarrierNode::decorators() const {
2884 return _decorators;
2885 }
2886
2887 uint ShenandoahLoadReferenceBarrierNode::size_of() const {
2888 return sizeof(*this);
2889 }
2890
2891 static DecoratorSet mask_decorators(DecoratorSet decorators) {
2892 return decorators & (ON_STRONG_OOP_REF | ON_WEAK_OOP_REF | ON_PHANTOM_OOP_REF | ON_UNKNOWN_OOP_REF | IN_NATIVE);
2893 }
2894
2895 uint ShenandoahLoadReferenceBarrierNode::hash() const {
2896 uint hash = Node::hash();
2897 hash += mask_decorators(_decorators);
2898 return hash;
2899 }
2900
2901 bool ShenandoahLoadReferenceBarrierNode::cmp( const Node &n ) const {
2902 return Node::cmp(n) && n.Opcode() == Op_ShenandoahLoadReferenceBarrier &&
2903 mask_decorators(_decorators) == mask_decorators(((const ShenandoahLoadReferenceBarrierNode&)n)._decorators);
2904 }
2905
2906 const Type* ShenandoahLoadReferenceBarrierNode::bottom_type() const {
2907 if (in(ValueIn) == nullptr || in(ValueIn)->is_top()) {
2908 return Type::TOP;
2909 }
2910 const Type* t = in(ValueIn)->bottom_type();
2911 if (t == TypePtr::NULL_PTR) {
2912 return t;
2913 }
2914
2915 if (ShenandoahBarrierSet::is_strong_access(decorators())) {
2916 return t;
2917 }
2918
2919 return t->meet(TypePtr::NULL_PTR);
2920 }
2921
2922 const Type* ShenandoahLoadReferenceBarrierNode::Value(PhaseGVN* phase) const {
2923 // Either input is TOP ==> the result is TOP
2924 const Type *t2 = phase->type(in(ValueIn));
2925 if( t2 == Type::TOP ) return Type::TOP;
2926
2927 if (t2 == TypePtr::NULL_PTR) {
2928 return t2;
2929 }
2930
2931 if (ShenandoahBarrierSet::is_strong_access(decorators())) {
2932 return t2;
2933 }
2934
2935 return t2->meet(TypePtr::NULL_PTR);
2936 }
2937
2938 Node* ShenandoahLoadReferenceBarrierNode::Identity(PhaseGVN* phase) {
2939 Node* value = in(ValueIn);
2940 if (!needs_barrier(phase, value)) {
2941 return value;
2942 }
2943 return this;
2944 }
2945
2946 bool ShenandoahLoadReferenceBarrierNode::needs_barrier(PhaseGVN* phase, Node* n) {
2947 Unique_Node_List visited;
2948 return needs_barrier_impl(phase, n, visited);
2949 }
2950
2951 bool ShenandoahLoadReferenceBarrierNode::needs_barrier_impl(PhaseGVN* phase, Node* n, Unique_Node_List &visited) {
2952 if (n == nullptr) return false;
2953 if (visited.member(n)) {
2954 return false; // Been there.
2955 }
2956 visited.push(n);
2957
2958 if (n->is_Allocate()) {
2959 // tty->print_cr("optimize barrier on alloc");
2960 return false;
2961 }
2962 if (n->is_Call()) {
2963 // tty->print_cr("optimize barrier on call");
2964 return false;
2965 }
2966
2967 const Type* type = phase->type(n);
2968 if (type == Type::TOP) {
2969 return false;
2970 }
2971 if (type->make_ptr()->higher_equal(TypePtr::NULL_PTR)) {
2972 // tty->print_cr("optimize barrier on null");
2973 return false;
2974 }
2975 if (type->make_oopptr() && type->make_oopptr()->const_oop() != nullptr) {
2976 // tty->print_cr("optimize barrier on constant");
2977 return false;
2978 }
2979
2980 switch (n->Opcode()) {
2981 case Op_AddP:
2982 return true; // TODO: Can refine?
2983 case Op_LoadP:
2984 case Op_ShenandoahCompareAndExchangeN:
2985 case Op_ShenandoahCompareAndExchangeP:
2986 case Op_CompareAndExchangeN:
2987 case Op_CompareAndExchangeP:
2988 case Op_GetAndSetN:
2989 case Op_GetAndSetP:
2990 return true;
2991 case Op_Phi: {
2992 for (uint i = 1; i < n->req(); i++) {
2993 if (needs_barrier_impl(phase, n->in(i), visited)) return true;
2994 }
2995 return false;
2996 }
2997 case Op_CheckCastPP:
2998 case Op_CastPP:
2999 return needs_barrier_impl(phase, n->in(1), visited);
3000 case Op_Proj:
3001 return needs_barrier_impl(phase, n->in(0), visited);
3002 case Op_ShenandoahLoadReferenceBarrier:
3003 // tty->print_cr("optimize barrier on barrier");
3004 return false;
3005 case Op_Parm:
3006 // tty->print_cr("optimize barrier on input arg");
3007 return false;
3008 case Op_DecodeN:
3009 case Op_EncodeP:
3010 return needs_barrier_impl(phase, n->in(1), visited);
3011 case Op_LoadN:
3012 return true;
3013 case Op_CMoveN:
3014 case Op_CMoveP:
3015 return needs_barrier_impl(phase, n->in(2), visited) ||
3016 needs_barrier_impl(phase, n->in(3), visited);
3017 case Op_ShenandoahIUBarrier:
3018 return needs_barrier_impl(phase, n->in(1), visited);
3019 case Op_CreateEx:
3020 return false;
3021 default:
3022 break;
3023 }
3024 #ifdef ASSERT
3025 tty->print("need barrier on?: ");
3026 tty->print_cr("ins:");
3027 n->dump(2);
3028 tty->print_cr("outs:");
3029 n->dump(-2);
3030 ShouldNotReachHere();
3031 #endif
3032 return true;
3033 }