1 /*
2 * Copyright (c) 2015, 2021, Red Hat, Inc. All rights reserved.
3 * Copyright (C) 2022 THL A29 Limited, a Tencent company. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.hpp"
27
28 #include "classfile/javaClasses.hpp"
29 #include "gc/shenandoah/c2/shenandoahSupport.hpp"
30 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
31 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp"
32 #include "gc/shenandoah/shenandoahForwarding.hpp"
33 #include "gc/shenandoah/shenandoahHeap.hpp"
34 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
35 #include "gc/shenandoah/shenandoahRuntime.hpp"
36 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
37 #include "opto/arraycopynode.hpp"
38 #include "opto/block.hpp"
39 #include "opto/callnode.hpp"
40 #include "opto/castnode.hpp"
41 #include "opto/movenode.hpp"
42 #include "opto/phaseX.hpp"
43 #include "opto/rootnode.hpp"
44 #include "opto/runtime.hpp"
45 #include "opto/subnode.hpp"
46
47 bool ShenandoahBarrierC2Support::expand(Compile* C, PhaseIterGVN& igvn) {
48 ShenandoahBarrierSetC2State* state = ShenandoahBarrierSetC2::bsc2()->state();
49 if ((state->iu_barriers_count() +
50 state->load_reference_barriers_count()) > 0) {
51 assert(C->post_loop_opts_phase(), "no loop opts allowed");
52 C->reset_post_loop_opts_phase(); // ... but we know what we are doing
53 bool attempt_more_loopopts = ShenandoahLoopOptsAfterExpansion;
54 C->clear_major_progress();
55 PhaseIdealLoop::optimize(igvn, LoopOptsShenandoahExpand);
56 if (C->failing()) return false;
57 PhaseIdealLoop::verify(igvn);
58 if (attempt_more_loopopts) {
59 C->set_major_progress();
60 if (!C->optimize_loops(igvn, LoopOptsShenandoahPostExpand)) {
61 return false;
62 }
63 C->clear_major_progress();
64
65 C->process_for_post_loop_opts_igvn(igvn);
66 }
67 C->set_post_loop_opts_phase(); // now for real!
68 }
69 return true;
70 }
71
72 bool ShenandoahBarrierC2Support::is_gc_state_test(Node* iff, int mask) {
73 if (!UseShenandoahGC) {
74 return false;
75 }
76 assert(iff->is_If(), "bad input");
77 if (iff->Opcode() != Op_If) {
78 return false;
79 }
80 Node* bol = iff->in(1);
81 if (!bol->is_Bool() || bol->as_Bool()->_test._test != BoolTest::ne) {
82 return false;
83 }
84 Node* cmp = bol->in(1);
85 if (cmp->Opcode() != Op_CmpI) {
86 return false;
87 }
88 Node* in1 = cmp->in(1);
89 Node* in2 = cmp->in(2);
90 if (in2->find_int_con(-1) != 0) {
91 return false;
92 }
93 if (in1->Opcode() != Op_AndI) {
94 return false;
95 }
96 in2 = in1->in(2);
97 if (in2->find_int_con(-1) != mask) {
98 return false;
99 }
100 in1 = in1->in(1);
101
102 return is_gc_state_load(in1);
103 }
104
105 bool ShenandoahBarrierC2Support::is_heap_stable_test(Node* iff) {
106 return is_gc_state_test(iff, ShenandoahHeap::HAS_FORWARDED);
107 }
108
109 bool ShenandoahBarrierC2Support::is_gc_state_load(Node *n) {
110 if (!UseShenandoahGC) {
111 return false;
112 }
113 if (n->Opcode() != Op_LoadB && n->Opcode() != Op_LoadUB) {
114 return false;
115 }
116 Node* addp = n->in(MemNode::Address);
117 if (!addp->is_AddP()) {
118 return false;
119 }
120 Node* base = addp->in(AddPNode::Address);
121 Node* off = addp->in(AddPNode::Offset);
122 if (base->Opcode() != Op_ThreadLocal) {
123 return false;
124 }
125 if (off->find_intptr_t_con(-1) != in_bytes(ShenandoahThreadLocalData::gc_state_offset())) {
126 return false;
127 }
128 return true;
129 }
130
131 bool ShenandoahBarrierC2Support::has_safepoint_between(Node* start, Node* stop, PhaseIdealLoop *phase) {
132 assert(phase->is_dominator(stop, start), "bad inputs");
133 ResourceMark rm;
134 Unique_Node_List wq;
135 wq.push(start);
136 for (uint next = 0; next < wq.size(); next++) {
137 Node *m = wq.at(next);
138 if (m == stop) {
139 continue;
140 }
141 if (m->is_SafePoint() && !m->is_CallLeaf()) {
142 return true;
143 }
144 if (m->is_Region()) {
145 for (uint i = 1; i < m->req(); i++) {
146 wq.push(m->in(i));
147 }
148 } else {
149 wq.push(m->in(0));
150 }
151 }
152 return false;
153 }
154
155 #ifdef ASSERT
156 bool ShenandoahBarrierC2Support::verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used) {
157 assert(phis.size() == 0, "");
158
159 while (true) {
160 if (in->bottom_type() == TypePtr::NULL_PTR) {
161 if (trace) {tty->print_cr("null");}
162 } else if (!in->bottom_type()->make_ptr()->make_oopptr()) {
163 if (trace) {tty->print_cr("Non oop");}
164 } else {
165 if (in->is_ConstraintCast()) {
166 in = in->in(1);
167 continue;
168 } else if (in->is_AddP()) {
169 assert(!in->in(AddPNode::Address)->is_top(), "no raw memory access");
170 in = in->in(AddPNode::Address);
171 continue;
172 } else if (in->is_Con()) {
173 if (trace) {
174 tty->print("Found constant");
175 in->dump();
176 }
177 } else if (in->Opcode() == Op_Parm) {
178 if (trace) {
179 tty->print("Found argument");
180 }
181 } else if (in->Opcode() == Op_CreateEx) {
182 if (trace) {
183 tty->print("Found create-exception");
184 }
185 } else if (in->Opcode() == Op_LoadP && in->adr_type() == TypeRawPtr::BOTTOM) {
186 if (trace) {
187 tty->print("Found raw LoadP (OSR argument?)");
188 }
189 } else if (in->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
190 if (t == ShenandoahOopStore) {
191 uint i = 0;
192 for (; i < phis.size(); i++) {
193 Node* n = phis.node_at(i);
194 if (n->Opcode() == Op_ShenandoahIUBarrier) {
195 break;
196 }
197 }
198 if (i == phis.size()) {
199 return false;
200 }
201 }
202 barriers_used.push(in);
203 if (trace) {tty->print("Found barrier"); in->dump();}
204 } else if (in->Opcode() == Op_ShenandoahIUBarrier) {
205 if (t != ShenandoahOopStore) {
206 in = in->in(1);
207 continue;
208 }
209 if (trace) {tty->print("Found enqueue barrier"); in->dump();}
210 phis.push(in, in->req());
211 in = in->in(1);
212 continue;
213 } else if (in->is_Proj() && in->in(0)->is_Allocate()) {
214 if (trace) {
215 tty->print("Found alloc");
216 in->in(0)->dump();
217 }
218 } else if (in->is_Proj() && (in->in(0)->Opcode() == Op_CallStaticJava || in->in(0)->Opcode() == Op_CallDynamicJava)) {
219 if (trace) {
220 tty->print("Found Java call");
221 }
222 } else if (in->is_Phi()) {
223 if (!visited.test_set(in->_idx)) {
224 if (trace) {tty->print("Pushed phi:"); in->dump();}
225 phis.push(in, 2);
226 in = in->in(1);
227 continue;
228 }
229 if (trace) {tty->print("Already seen phi:"); in->dump();}
230 } else if (in->Opcode() == Op_CMoveP || in->Opcode() == Op_CMoveN) {
231 if (!visited.test_set(in->_idx)) {
232 if (trace) {tty->print("Pushed cmovep:"); in->dump();}
233 phis.push(in, CMoveNode::IfTrue);
234 in = in->in(CMoveNode::IfFalse);
235 continue;
236 }
237 if (trace) {tty->print("Already seen cmovep:"); in->dump();}
238 } else if (in->Opcode() == Op_EncodeP || in->Opcode() == Op_DecodeN) {
239 in = in->in(1);
240 continue;
241 } else {
242 return false;
243 }
244 }
245 bool cont = false;
246 while (phis.is_nonempty()) {
247 uint idx = phis.index();
248 Node* phi = phis.node();
249 if (idx >= phi->req()) {
250 if (trace) {tty->print("Popped phi:"); phi->dump();}
251 phis.pop();
252 continue;
253 }
254 if (trace) {tty->print("Next entry(%d) for phi:", idx); phi->dump();}
255 in = phi->in(idx);
256 phis.set_index(idx+1);
257 cont = true;
258 break;
259 }
260 if (!cont) {
261 break;
262 }
263 }
264 return true;
265 }
266
267 void ShenandoahBarrierC2Support::report_verify_failure(const char* msg, Node* n1, Node* n2) {
268 if (n1 != nullptr) {
269 n1->dump(+10);
270 }
271 if (n2 != nullptr) {
272 n2->dump(+10);
273 }
274 fatal("%s", msg);
275 }
276
277 void ShenandoahBarrierC2Support::verify(RootNode* root) {
278 ResourceMark rm;
279 Unique_Node_List wq;
280 GrowableArray<Node*> barriers;
281 Unique_Node_List barriers_used;
282 Node_Stack phis(0);
283 VectorSet visited;
284 const bool trace = false;
285 const bool verify_no_useless_barrier = false;
286
287 wq.push(root);
288 for (uint next = 0; next < wq.size(); next++) {
289 Node *n = wq.at(next);
290 if (n->is_Load()) {
291 const bool trace = false;
292 if (trace) {tty->print("Verifying"); n->dump();}
293 if (n->Opcode() == Op_LoadRange || n->Opcode() == Op_LoadKlass || n->Opcode() == Op_LoadNKlass) {
294 if (trace) {tty->print_cr("Load range/klass");}
295 } else {
296 const TypePtr* adr_type = n->as_Load()->adr_type();
297
298 if (adr_type->isa_oopptr() && adr_type->is_oopptr()->offset() == oopDesc::mark_offset_in_bytes()) {
299 if (trace) {tty->print_cr("Mark load");}
300 } else if (adr_type->isa_instptr() &&
301 adr_type->is_instptr()->instance_klass()->is_subtype_of(Compile::current()->env()->Reference_klass()) &&
302 adr_type->is_instptr()->offset() == java_lang_ref_Reference::referent_offset()) {
303 if (trace) {tty->print_cr("Reference.get()");}
304 } else if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahLoad, trace, barriers_used)) {
305 report_verify_failure("Shenandoah verification: Load should have barriers", n);
306 }
307 }
308 } else if (n->is_Store()) {
309 const bool trace = false;
310
311 if (trace) {tty->print("Verifying"); n->dump();}
312 if (n->in(MemNode::ValueIn)->bottom_type()->make_oopptr()) {
313 Node* adr = n->in(MemNode::Address);
314 bool verify = true;
315
316 if (adr->is_AddP() && adr->in(AddPNode::Base)->is_top()) {
317 adr = adr->in(AddPNode::Address);
318 if (adr->is_AddP()) {
319 assert(adr->in(AddPNode::Base)->is_top(), "");
320 adr = adr->in(AddPNode::Address);
321 if (adr->Opcode() == Op_LoadP &&
322 adr->in(MemNode::Address)->in(AddPNode::Base)->is_top() &&
323 adr->in(MemNode::Address)->in(AddPNode::Address)->Opcode() == Op_ThreadLocal &&
324 adr->in(MemNode::Address)->in(AddPNode::Offset)->find_intptr_t_con(-1) == in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset())) {
325 if (trace) {tty->print_cr("SATB prebarrier");}
326 verify = false;
327 }
328 }
329 }
330
331 if (verify && !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahIUBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
332 report_verify_failure("Shenandoah verification: Store should have barriers", n);
333 }
334 }
335 if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
336 report_verify_failure("Shenandoah verification: Store (address) should have barriers", n);
337 }
338 } else if (n->Opcode() == Op_CmpP) {
339 const bool trace = false;
340
341 Node* in1 = n->in(1);
342 Node* in2 = n->in(2);
343 if (in1->bottom_type()->isa_oopptr()) {
344 if (trace) {tty->print("Verifying"); n->dump();}
345
346 bool mark_inputs = false;
347 if (in1->bottom_type() == TypePtr::NULL_PTR || in2->bottom_type() == TypePtr::NULL_PTR ||
348 (in1->is_Con() || in2->is_Con())) {
349 if (trace) {tty->print_cr("Comparison against a constant");}
350 mark_inputs = true;
351 } else if ((in1->is_CheckCastPP() && in1->in(1)->is_Proj() && in1->in(1)->in(0)->is_Allocate()) ||
352 (in2->is_CheckCastPP() && in2->in(1)->is_Proj() && in2->in(1)->in(0)->is_Allocate())) {
353 if (trace) {tty->print_cr("Comparison with newly alloc'ed object");}
354 mark_inputs = true;
355 } else {
356 assert(in2->bottom_type()->isa_oopptr(), "");
357
358 if (!verify_helper(in1, phis, visited, ShenandoahStore, trace, barriers_used) ||
359 !verify_helper(in2, phis, visited, ShenandoahStore, trace, barriers_used)) {
360 report_verify_failure("Shenandoah verification: Cmp should have barriers", n);
361 }
362 }
363 if (verify_no_useless_barrier &&
364 mark_inputs &&
365 (!verify_helper(in1, phis, visited, ShenandoahValue, trace, barriers_used) ||
366 !verify_helper(in2, phis, visited, ShenandoahValue, trace, barriers_used))) {
367 phis.clear();
368 visited.reset();
369 }
370 }
371 } else if (n->is_LoadStore()) {
372 if (n->in(MemNode::ValueIn)->bottom_type()->make_ptr() &&
373 !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahIUBarrier ? ShenandoahOopStore : ShenandoahValue, trace, barriers_used)) {
374 report_verify_failure("Shenandoah verification: LoadStore (value) should have barriers", n);
375 }
376
377 if (n->in(MemNode::Address)->bottom_type()->make_oopptr() && !verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
378 report_verify_failure("Shenandoah verification: LoadStore (address) should have barriers", n);
379 }
380 } else if (n->Opcode() == Op_CallLeafNoFP || n->Opcode() == Op_CallLeaf) {
381 CallNode* call = n->as_Call();
382
383 static struct {
384 const char* name;
385 struct {
386 int pos;
387 verify_type t;
388 } args[6];
389 } calls[] = {
390 "aescrypt_encryptBlock",
391 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
392 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
393 "aescrypt_decryptBlock",
394 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
395 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
396 "multiplyToLen",
397 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { TypeFunc::Parms+4, ShenandoahStore },
398 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
399 "squareToLen",
400 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { -1, ShenandoahNone},
401 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
402 "montgomery_multiply",
403 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
404 { TypeFunc::Parms+6, ShenandoahStore }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
405 "montgomery_square",
406 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+5, ShenandoahStore },
407 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
408 "mulAdd",
409 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
410 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
411 "vectorizedMismatch",
412 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
413 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
414 "updateBytesCRC32",
415 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
416 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
417 "updateBytesAdler32",
418 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
419 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
420 "updateBytesCRC32C",
421 { { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahLoad}, { -1, ShenandoahNone},
422 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
423 "counterMode_AESCrypt",
424 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
425 { TypeFunc::Parms+3, ShenandoahStore }, { TypeFunc::Parms+5, ShenandoahStore }, { TypeFunc::Parms+6, ShenandoahStore } },
426 "cipherBlockChaining_encryptAESCrypt",
427 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
428 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
429 "cipherBlockChaining_decryptAESCrypt",
430 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
431 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
432 "shenandoah_clone_barrier",
433 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
434 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
435 "ghash_processBlocks",
436 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
437 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
438 "sha1_implCompress",
439 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
440 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
441 "sha256_implCompress",
442 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
443 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
444 "sha512_implCompress",
445 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
446 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
447 "sha1_implCompressMB",
448 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
449 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
450 "sha256_implCompressMB",
451 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
452 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
453 "sha512_implCompressMB",
454 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
455 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
456 "encodeBlock",
457 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
458 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
459 "decodeBlock",
460 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
461 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
462 };
463
464 if (call->is_call_to_arraycopystub()) {
465 Node* dest = nullptr;
466 const TypeTuple* args = n->as_Call()->_tf->domain();
467 for (uint i = TypeFunc::Parms, j = 0; i < args->cnt(); i++) {
468 if (args->field_at(i)->isa_ptr()) {
469 j++;
470 if (j == 2) {
471 dest = n->in(i);
472 break;
473 }
474 }
475 }
476 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahLoad, trace, barriers_used) ||
477 !verify_helper(dest, phis, visited, ShenandoahStore, trace, barriers_used)) {
478 report_verify_failure("Shenandoah verification: ArrayCopy should have barriers", n);
479 }
480 } else if (strlen(call->_name) > 5 &&
481 !strcmp(call->_name + strlen(call->_name) - 5, "_fill")) {
482 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahStore, trace, barriers_used)) {
483 report_verify_failure("Shenandoah verification: _fill should have barriers", n);
484 }
485 } else if (!strcmp(call->_name, "shenandoah_wb_pre")) {
486 // skip
487 } else {
488 const int calls_len = sizeof(calls) / sizeof(calls[0]);
489 int i = 0;
490 for (; i < calls_len; i++) {
491 if (!strcmp(calls[i].name, call->_name)) {
492 break;
493 }
494 }
495 if (i != calls_len) {
496 const uint args_len = sizeof(calls[0].args) / sizeof(calls[0].args[0]);
497 for (uint j = 0; j < args_len; j++) {
498 int pos = calls[i].args[j].pos;
499 if (pos == -1) {
500 break;
501 }
502 if (!verify_helper(call->in(pos), phis, visited, calls[i].args[j].t, trace, barriers_used)) {
503 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
504 }
505 }
506 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
507 if (call->in(j)->bottom_type()->make_ptr() &&
508 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
509 uint k = 0;
510 for (; k < args_len && calls[i].args[k].pos != (int)j; k++);
511 if (k == args_len) {
512 fatal("arg %d for call %s not covered", j, call->_name);
513 }
514 }
515 }
516 } else {
517 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
518 if (call->in(j)->bottom_type()->make_ptr() &&
519 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
520 fatal("%s not covered", call->_name);
521 }
522 }
523 }
524 }
525 } else if (n->Opcode() == Op_ShenandoahIUBarrier || n->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
526 // skip
527 } else if (n->is_AddP()
528 || n->is_Phi()
529 || n->is_ConstraintCast()
530 || n->Opcode() == Op_Return
531 || n->Opcode() == Op_CMoveP
532 || n->Opcode() == Op_CMoveN
533 || n->Opcode() == Op_Rethrow
534 || n->is_MemBar()
535 || n->Opcode() == Op_Conv2B
536 || n->Opcode() == Op_SafePoint
537 || n->is_CallJava()
538 || n->Opcode() == Op_Unlock
539 || n->Opcode() == Op_EncodeP
540 || n->Opcode() == Op_DecodeN) {
541 // nothing to do
542 } else {
543 static struct {
544 int opcode;
545 struct {
546 int pos;
547 verify_type t;
548 } inputs[2];
549 } others[] = {
550 Op_FastLock,
551 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
552 Op_Lock,
553 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone} },
554 Op_ArrayCopy,
555 { { ArrayCopyNode::Src, ShenandoahLoad }, { ArrayCopyNode::Dest, ShenandoahStore } },
556 Op_StrCompressedCopy,
557 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
558 Op_StrInflatedCopy,
559 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
560 Op_AryEq,
561 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
562 Op_StrIndexOf,
563 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
564 Op_StrComp,
565 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
566 Op_StrEquals,
567 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
568 Op_VectorizedHashCode,
569 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
570 Op_EncodeISOArray,
571 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
572 Op_CountPositives,
573 { { 2, ShenandoahLoad }, { -1, ShenandoahNone} },
574 Op_CastP2X,
575 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
576 Op_StrIndexOfChar,
577 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
578 };
579
580 const int others_len = sizeof(others) / sizeof(others[0]);
581 int i = 0;
582 for (; i < others_len; i++) {
583 if (others[i].opcode == n->Opcode()) {
584 break;
585 }
586 }
587 uint stop = n->is_Call() ? n->as_Call()->tf()->domain()->cnt() : n->req();
588 if (i != others_len) {
589 const uint inputs_len = sizeof(others[0].inputs) / sizeof(others[0].inputs[0]);
590 for (uint j = 0; j < inputs_len; j++) {
591 int pos = others[i].inputs[j].pos;
592 if (pos == -1) {
593 break;
594 }
595 if (!verify_helper(n->in(pos), phis, visited, others[i].inputs[j].t, trace, barriers_used)) {
596 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
597 }
598 }
599 for (uint j = 1; j < stop; j++) {
600 if (n->in(j) != nullptr && n->in(j)->bottom_type()->make_ptr() &&
601 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
602 uint k = 0;
603 for (; k < inputs_len && others[i].inputs[k].pos != (int)j; k++);
604 if (k == inputs_len) {
605 fatal("arg %d for node %s not covered", j, n->Name());
606 }
607 }
608 }
609 } else {
610 for (uint j = 1; j < stop; j++) {
611 if (n->in(j) != nullptr && n->in(j)->bottom_type()->make_ptr() &&
612 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
613 fatal("%s not covered", n->Name());
614 }
615 }
616 }
617 }
618
619 if (n->is_SafePoint()) {
620 SafePointNode* sfpt = n->as_SafePoint();
621 if (verify_no_useless_barrier && sfpt->jvms() != nullptr) {
622 for (uint i = sfpt->jvms()->scloff(); i < sfpt->jvms()->endoff(); i++) {
623 if (!verify_helper(sfpt->in(i), phis, visited, ShenandoahLoad, trace, barriers_used)) {
624 phis.clear();
625 visited.reset();
626 }
627 }
628 }
629 }
630 }
631
632 if (verify_no_useless_barrier) {
633 for (int i = 0; i < barriers.length(); i++) {
634 Node* n = barriers.at(i);
635 if (!barriers_used.member(n)) {
636 tty->print("XXX useless barrier"); n->dump(-2);
637 ShouldNotReachHere();
638 }
639 }
640 }
641 }
642 #endif
643
644 bool ShenandoahBarrierC2Support::is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase) {
645 // That both nodes have the same control is not sufficient to prove
646 // domination, verify that there's no path from d to n
647 ResourceMark rm;
648 Unique_Node_List wq;
649 wq.push(d);
650 for (uint next = 0; next < wq.size(); next++) {
651 Node *m = wq.at(next);
652 if (m == n) {
653 return false;
654 }
655 if (m->is_Phi() && m->in(0)->is_Loop()) {
656 assert(phase->ctrl_or_self(m->in(LoopNode::EntryControl)) != c, "following loop entry should lead to new control");
657 } else {
658 if (m->is_Store() || m->is_LoadStore()) {
659 // Take anti-dependencies into account
660 Node* mem = m->in(MemNode::Memory);
661 for (DUIterator_Fast imax, i = mem->fast_outs(imax); i < imax; i++) {
662 Node* u = mem->fast_out(i);
663 if (u->is_Load() && phase->C->can_alias(m->adr_type(), phase->C->get_alias_index(u->adr_type())) &&
664 phase->ctrl_or_self(u) == c) {
665 wq.push(u);
666 }
667 }
668 }
669 for (uint i = 0; i < m->req(); i++) {
670 if (m->in(i) != nullptr && phase->ctrl_or_self(m->in(i)) == c) {
671 wq.push(m->in(i));
672 }
673 }
674 }
675 }
676 return true;
677 }
678
679 bool ShenandoahBarrierC2Support::is_dominator(Node* d_c, Node* n_c, Node* d, Node* n, PhaseIdealLoop* phase) {
680 if (d_c != n_c) {
681 return phase->is_dominator(d_c, n_c);
682 }
683 return is_dominator_same_ctrl(d_c, d, n, phase);
684 }
685
686 Node* next_mem(Node* mem, int alias) {
687 Node* res = nullptr;
688 if (mem->is_Proj()) {
689 res = mem->in(0);
690 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
691 res = mem->in(TypeFunc::Memory);
692 } else if (mem->is_Phi()) {
693 res = mem->in(1);
694 } else if (mem->is_MergeMem()) {
695 res = mem->as_MergeMem()->memory_at(alias);
696 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
697 assert(alias == Compile::AliasIdxRaw, "following raw memory can't lead to a barrier");
698 res = mem->in(MemNode::Memory);
699 } else {
700 #ifdef ASSERT
701 mem->dump();
702 #endif
703 ShouldNotReachHere();
704 }
705 return res;
706 }
707
708 Node* ShenandoahBarrierC2Support::no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase) {
709 Node* iffproj = nullptr;
710 while (c != dom) {
711 Node* next = phase->idom(c);
712 assert(next->unique_ctrl_out_or_null() == c || c->is_Proj() || c->is_Region(), "multiple control flow out but no proj or region?");
713 if (c->is_Region()) {
714 ResourceMark rm;
715 Unique_Node_List wq;
716 wq.push(c);
717 for (uint i = 0; i < wq.size(); i++) {
718 Node *n = wq.at(i);
719 if (n == next) {
720 continue;
721 }
722 if (n->is_Region()) {
723 for (uint j = 1; j < n->req(); j++) {
724 wq.push(n->in(j));
725 }
726 } else {
727 wq.push(n->in(0));
728 }
729 }
730 for (uint i = 0; i < wq.size(); i++) {
731 Node *n = wq.at(i);
732 assert(n->is_CFG(), "");
733 if (n->is_Multi()) {
734 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
735 Node* u = n->fast_out(j);
736 if (u->is_CFG()) {
737 if (!wq.member(u) && !u->as_Proj()->is_uncommon_trap_proj(Deoptimization::Reason_none)) {
738 return NodeSentinel;
739 }
740 }
741 }
742 }
743 }
744 } else if (c->is_Proj()) {
745 if (c->is_IfProj()) {
746 if (c->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) != nullptr) {
747 // continue;
748 } else {
749 if (!allow_one_proj) {
750 return NodeSentinel;
751 }
752 if (iffproj == nullptr) {
753 iffproj = c;
754 } else {
755 return NodeSentinel;
756 }
757 }
758 } else if (c->Opcode() == Op_JumpProj) {
759 return NodeSentinel; // unsupported
760 } else if (c->Opcode() == Op_CatchProj) {
761 return NodeSentinel; // unsupported
762 } else if (c->Opcode() == Op_CProj && next->is_NeverBranch()) {
763 return NodeSentinel; // unsupported
764 } else {
765 assert(next->unique_ctrl_out() == c, "unsupported branch pattern");
766 }
767 }
768 c = next;
769 }
770 return iffproj;
771 }
772
773 Node* ShenandoahBarrierC2Support::dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase) {
774 ResourceMark rm;
775 VectorSet wq;
776 wq.set(mem->_idx);
777 mem_ctrl = phase->ctrl_or_self(mem);
778 while (!phase->is_dominator(mem_ctrl, ctrl) || mem_ctrl == ctrl) {
779 mem = next_mem(mem, alias);
780 if (wq.test_set(mem->_idx)) {
781 return nullptr;
782 }
783 mem_ctrl = phase->ctrl_or_self(mem);
784 }
785 if (mem->is_MergeMem()) {
786 mem = mem->as_MergeMem()->memory_at(alias);
787 mem_ctrl = phase->ctrl_or_self(mem);
788 }
789 return mem;
790 }
791
792 Node* ShenandoahBarrierC2Support::find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase) {
793 Node* mem = nullptr;
794 Node* c = ctrl;
795 do {
796 if (c->is_Region()) {
797 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax && mem == nullptr; i++) {
798 Node* u = c->fast_out(i);
799 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
800 if (u->adr_type() == TypePtr::BOTTOM) {
801 mem = u;
802 }
803 }
804 }
805 } else {
806 if (c->is_Call() && c->as_Call()->adr_type() != nullptr) {
807 CallProjections projs;
808 c->as_Call()->extract_projections(&projs, true, false);
809 if (projs.fallthrough_memproj != nullptr) {
810 if (projs.fallthrough_memproj->adr_type() == TypePtr::BOTTOM) {
811 if (projs.catchall_memproj == nullptr) {
812 mem = projs.fallthrough_memproj;
813 } else {
814 if (phase->is_dominator(projs.fallthrough_catchproj, ctrl)) {
815 mem = projs.fallthrough_memproj;
816 } else {
817 assert(phase->is_dominator(projs.catchall_catchproj, ctrl), "one proj must dominate barrier");
818 mem = projs.catchall_memproj;
819 }
820 }
821 }
822 } else {
823 Node* proj = c->as_Call()->proj_out(TypeFunc::Memory);
824 if (proj != nullptr &&
825 proj->adr_type() == TypePtr::BOTTOM) {
826 mem = proj;
827 }
828 }
829 } else {
830 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
831 Node* u = c->fast_out(i);
832 if (u->is_Proj() &&
833 u->bottom_type() == Type::MEMORY &&
834 u->adr_type() == TypePtr::BOTTOM) {
835 assert(c->is_SafePoint() || c->is_MemBar() || c->is_Start(), "");
836 assert(mem == nullptr, "only one proj");
837 mem = u;
838 }
839 }
840 assert(!c->is_Call() || c->as_Call()->adr_type() != nullptr || mem == nullptr, "no mem projection expected");
841 }
842 }
843 c = phase->idom(c);
844 } while (mem == nullptr);
845 return mem;
846 }
847
848 void ShenandoahBarrierC2Support::follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase) {
849 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
850 Node* u = n->fast_out(i);
851 if (!u->is_CFG() && phase->get_ctrl(u) == ctrl && (!u->is_Phi() || !u->in(0)->is_Loop() || u->in(LoopNode::LoopBackControl) != n)) {
852 uses.push(u);
853 }
854 }
855 }
856
857 static void hide_strip_mined_loop(OuterStripMinedLoopNode* outer, CountedLoopNode* inner, PhaseIdealLoop* phase) {
858 OuterStripMinedLoopEndNode* le = inner->outer_loop_end();
859 Node* new_outer = new LoopNode(outer->in(LoopNode::EntryControl), outer->in(LoopNode::LoopBackControl));
860 phase->register_control(new_outer, phase->get_loop(outer), outer->in(LoopNode::EntryControl));
861 Node* new_le = new IfNode(le->in(0), le->in(1), le->_prob, le->_fcnt);
862 phase->register_control(new_le, phase->get_loop(le), le->in(0));
863 phase->lazy_replace(outer, new_outer);
864 phase->lazy_replace(le, new_le);
865 inner->clear_strip_mined();
866 }
867
868 void ShenandoahBarrierC2Support::test_gc_state(Node*& ctrl, Node* raw_mem, Node*& test_fail_ctrl,
869 PhaseIdealLoop* phase, int flags) {
870 PhaseIterGVN& igvn = phase->igvn();
871 Node* old_ctrl = ctrl;
872
873 Node* thread = new ThreadLocalNode();
874 Node* gc_state_offset = igvn.MakeConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
875 Node* gc_state_addr = new AddPNode(phase->C->top(), thread, gc_state_offset);
876 Node* gc_state = new LoadBNode(old_ctrl, raw_mem, gc_state_addr,
877 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(nullptr),
878 TypeInt::BYTE, MemNode::unordered);
879 Node* gc_state_and = new AndINode(gc_state, igvn.intcon(flags));
880 Node* gc_state_cmp = new CmpINode(gc_state_and, igvn.zerocon(T_INT));
881 Node* gc_state_bool = new BoolNode(gc_state_cmp, BoolTest::ne);
882
883 IfNode* gc_state_iff = new IfNode(old_ctrl, gc_state_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
884 ctrl = new IfTrueNode(gc_state_iff);
885 test_fail_ctrl = new IfFalseNode(gc_state_iff);
886
887 IdealLoopTree* loop = phase->get_loop(old_ctrl);
888 phase->register_control(gc_state_iff, loop, old_ctrl);
889 phase->register_control(ctrl, loop, gc_state_iff);
890 phase->register_control(test_fail_ctrl, loop, gc_state_iff);
891
892 phase->register_new_node(thread, old_ctrl);
893 phase->register_new_node(gc_state_addr, old_ctrl);
894 phase->register_new_node(gc_state, old_ctrl);
895 phase->register_new_node(gc_state_and, old_ctrl);
896 phase->register_new_node(gc_state_cmp, old_ctrl);
897 phase->register_new_node(gc_state_bool, old_ctrl);
898
899 phase->set_ctrl(gc_state_offset, phase->C->root());
900
901 assert(is_gc_state_test(gc_state_iff, flags), "Should match the shape");
902 }
903
904 void ShenandoahBarrierC2Support::test_null(Node*& ctrl, Node* val, Node*& null_ctrl, PhaseIdealLoop* phase) {
905 Node* old_ctrl = ctrl;
906 PhaseIterGVN& igvn = phase->igvn();
907
908 const Type* val_t = igvn.type(val);
909 if (val_t->meet(TypePtr::NULL_PTR) == val_t) {
910 Node* null_cmp = new CmpPNode(val, igvn.zerocon(T_OBJECT));
911 Node* null_test = new BoolNode(null_cmp, BoolTest::ne);
912
913 IfNode* null_iff = new IfNode(old_ctrl, null_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
914 ctrl = new IfTrueNode(null_iff);
915 null_ctrl = new IfFalseNode(null_iff);
916
917 IdealLoopTree* loop = phase->get_loop(old_ctrl);
918 phase->register_control(null_iff, loop, old_ctrl);
919 phase->register_control(ctrl, loop, null_iff);
920 phase->register_control(null_ctrl, loop, null_iff);
921
922 phase->register_new_node(null_cmp, old_ctrl);
923 phase->register_new_node(null_test, old_ctrl);
924 }
925 }
926
927 void ShenandoahBarrierC2Support::test_in_cset(Node*& ctrl, Node*& not_cset_ctrl, Node* val, Node* raw_mem, PhaseIdealLoop* phase) {
928 Node* old_ctrl = ctrl;
929 PhaseIterGVN& igvn = phase->igvn();
930
931 Node* raw_val = new CastP2XNode(old_ctrl, val);
932 Node* cset_idx = new URShiftXNode(raw_val, igvn.intcon(ShenandoahHeapRegion::region_size_bytes_shift_jint()));
933
934 // Figure out the target cset address with raw pointer math.
935 // This avoids matching AddP+LoadB that would emit inefficient code.
936 // See JDK-8245465.
937 Node* cset_addr_ptr = igvn.makecon(TypeRawPtr::make(ShenandoahHeap::in_cset_fast_test_addr()));
938 Node* cset_addr = new CastP2XNode(old_ctrl, cset_addr_ptr);
939 Node* cset_load_addr = new AddXNode(cset_addr, cset_idx);
940 Node* cset_load_ptr = new CastX2PNode(cset_load_addr);
941
942 Node* cset_load = new LoadBNode(old_ctrl, raw_mem, cset_load_ptr,
943 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(nullptr),
944 TypeInt::BYTE, MemNode::unordered);
945 Node* cset_cmp = new CmpINode(cset_load, igvn.zerocon(T_INT));
946 Node* cset_bool = new BoolNode(cset_cmp, BoolTest::ne);
947
948 IfNode* cset_iff = new IfNode(old_ctrl, cset_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
949 ctrl = new IfTrueNode(cset_iff);
950 not_cset_ctrl = new IfFalseNode(cset_iff);
951
952 IdealLoopTree *loop = phase->get_loop(old_ctrl);
953 phase->register_control(cset_iff, loop, old_ctrl);
954 phase->register_control(ctrl, loop, cset_iff);
955 phase->register_control(not_cset_ctrl, loop, cset_iff);
956
957 phase->set_ctrl(cset_addr_ptr, phase->C->root());
958
959 phase->register_new_node(raw_val, old_ctrl);
960 phase->register_new_node(cset_idx, old_ctrl);
961 phase->register_new_node(cset_addr, old_ctrl);
962 phase->register_new_node(cset_load_addr, old_ctrl);
963 phase->register_new_node(cset_load_ptr, old_ctrl);
964 phase->register_new_node(cset_load, old_ctrl);
965 phase->register_new_node(cset_cmp, old_ctrl);
966 phase->register_new_node(cset_bool, old_ctrl);
967 }
968
969 void ShenandoahBarrierC2Support::call_lrb_stub(Node*& ctrl, Node*& val, Node* load_addr,
970 DecoratorSet decorators, PhaseIdealLoop* phase) {
971 IdealLoopTree*loop = phase->get_loop(ctrl);
972 const TypePtr* obj_type = phase->igvn().type(val)->is_oopptr();
973
974 address calladdr = nullptr;
975 const char* name = nullptr;
976 bool is_strong = ShenandoahBarrierSet::is_strong_access(decorators);
977 bool is_weak = ShenandoahBarrierSet::is_weak_access(decorators);
978 bool is_phantom = ShenandoahBarrierSet::is_phantom_access(decorators);
979 bool is_native = ShenandoahBarrierSet::is_native_access(decorators);
980 bool is_narrow = UseCompressedOops && !is_native;
981 if (is_strong) {
982 if (is_narrow) {
983 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong_narrow);
984 name = "load_reference_barrier_strong_narrow";
985 } else {
986 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong);
987 name = "load_reference_barrier_strong";
988 }
989 } else if (is_weak) {
990 if (is_narrow) {
991 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak_narrow);
992 name = "load_reference_barrier_weak_narrow";
993 } else {
994 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak);
995 name = "load_reference_barrier_weak";
996 }
997 } else {
998 assert(is_phantom, "only remaining strength");
999 if (is_narrow) {
1000 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom_narrow);
1001 name = "load_reference_barrier_phantom_narrow";
1002 } else {
1003 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom);
1004 name = "load_reference_barrier_phantom";
1005 }
1006 }
1007 Node* call = new CallLeafNode(ShenandoahBarrierSetC2::shenandoah_load_reference_barrier_Type(), calladdr, name, TypeRawPtr::BOTTOM);
1008
1009 call->init_req(TypeFunc::Control, ctrl);
1010 call->init_req(TypeFunc::I_O, phase->C->top());
1011 call->init_req(TypeFunc::Memory, phase->C->top());
1012 call->init_req(TypeFunc::FramePtr, phase->C->top());
1013 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
1014 call->init_req(TypeFunc::Parms, val);
1015 call->init_req(TypeFunc::Parms+1, load_addr);
1016 phase->register_control(call, loop, ctrl);
1017 ctrl = new ProjNode(call, TypeFunc::Control);
1018 phase->register_control(ctrl, loop, call);
1019 val = new ProjNode(call, TypeFunc::Parms);
1020 phase->register_new_node(val, call);
1021 val = new CheckCastPPNode(ctrl, val, obj_type);
1022 phase->register_new_node(val, ctrl);
1023 }
1024
1025 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) {
1026 Node* ctrl = phase->get_ctrl(barrier);
1027 Node* init_raw_mem = fixer.find_mem(ctrl, barrier);
1028
1029 // Update the control of all nodes that should be after the
1030 // barrier control flow
1031 uses.clear();
1032 // Every node that is control dependent on the barrier's input
1033 // control will be after the expanded barrier. The raw memory (if
1034 // its memory is control dependent on the barrier's input control)
1035 // must stay above the barrier.
1036 uses_to_ignore.clear();
1037 if (phase->has_ctrl(init_raw_mem) && phase->get_ctrl(init_raw_mem) == ctrl && !init_raw_mem->is_Phi()) {
1038 uses_to_ignore.push(init_raw_mem);
1039 }
1040 for (uint next = 0; next < uses_to_ignore.size(); next++) {
1041 Node *n = uses_to_ignore.at(next);
1042 for (uint i = 0; i < n->req(); i++) {
1043 Node* in = n->in(i);
1044 if (in != nullptr && phase->has_ctrl(in) && phase->get_ctrl(in) == ctrl) {
1045 uses_to_ignore.push(in);
1046 }
1047 }
1048 }
1049 for (DUIterator_Fast imax, i = ctrl->fast_outs(imax); i < imax; i++) {
1050 Node* u = ctrl->fast_out(i);
1051 if (u->_idx < last &&
1052 u != barrier &&
1053 !uses_to_ignore.member(u) &&
1054 (u->in(0) != ctrl || (!u->is_Region() && !u->is_Phi())) &&
1055 (ctrl->Opcode() != Op_CatchProj || u->Opcode() != Op_CreateEx)) {
1056 Node* old_c = phase->ctrl_or_self(u);
1057 Node* c = old_c;
1058 if (c != ctrl ||
1059 is_dominator_same_ctrl(old_c, barrier, u, phase) ||
1060 ShenandoahBarrierSetC2::is_shenandoah_state_load(u)) {
1061 phase->igvn().rehash_node_delayed(u);
1062 int nb = u->replace_edge(ctrl, region, &phase->igvn());
1063 if (u->is_CFG()) {
1064 if (phase->idom(u) == ctrl) {
1065 phase->set_idom(u, region, phase->dom_depth(region));
1066 }
1067 } else if (phase->get_ctrl(u) == ctrl) {
1068 assert(u != init_raw_mem, "should leave input raw mem above the barrier");
1069 uses.push(u);
1070 }
1071 assert(nb == 1, "more than 1 ctrl input?");
1072 --i, imax -= nb;
1073 }
1074 }
1075 }
1076 }
1077
1078 static Node* create_phis_on_call_return(Node* ctrl, Node* c, Node* n, Node* n_clone, const CallProjections& projs, PhaseIdealLoop* phase) {
1079 Node* region = nullptr;
1080 while (c != ctrl) {
1081 if (c->is_Region()) {
1082 region = c;
1083 }
1084 c = phase->idom(c);
1085 }
1086 assert(region != nullptr, "");
1087 Node* phi = new PhiNode(region, n->bottom_type());
1088 for (uint j = 1; j < region->req(); j++) {
1089 Node* in = region->in(j);
1090 if (phase->is_dominator(projs.fallthrough_catchproj, in)) {
1091 phi->init_req(j, n);
1092 } else if (phase->is_dominator(projs.catchall_catchproj, in)) {
1093 phi->init_req(j, n_clone);
1094 } else {
1095 phi->init_req(j, create_phis_on_call_return(ctrl, in, n, n_clone, projs, phase));
1096 }
1097 }
1098 phase->register_new_node(phi, region);
1099 return phi;
1100 }
1101
1102 void ShenandoahBarrierC2Support::pin_and_expand(PhaseIdealLoop* phase) {
1103 ShenandoahBarrierSetC2State* state = ShenandoahBarrierSetC2::bsc2()->state();
1104
1105 Unique_Node_List uses;
1106 for (int i = 0; i < state->iu_barriers_count(); i++) {
1107 Node* barrier = state->iu_barrier(i);
1108 Node* ctrl = phase->get_ctrl(barrier);
1109 IdealLoopTree* loop = phase->get_loop(ctrl);
1110 Node* head = loop->head();
1111 if (head->is_OuterStripMinedLoop()) {
1112 // Expanding a barrier here will break loop strip mining
1113 // verification. Transform the loop so the loop nest doesn't
1114 // appear as strip mined.
1115 OuterStripMinedLoopNode* outer = head->as_OuterStripMinedLoop();
1116 hide_strip_mined_loop(outer, outer->unique_ctrl_out()->as_CountedLoop(), phase);
1117 }
1118 }
1119
1120 Node_Stack stack(0);
1121 Node_List clones;
1122 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1123 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1124
1125 Node* ctrl = phase->get_ctrl(lrb);
1126 Node* val = lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
1127
1128 CallStaticJavaNode* unc = nullptr;
1129 Node* unc_ctrl = nullptr;
1130 Node* uncasted_val = val;
1131
1132 for (DUIterator_Fast imax, i = lrb->fast_outs(imax); i < imax; i++) {
1133 Node* u = lrb->fast_out(i);
1134 if (u->Opcode() == Op_CastPP &&
1135 u->in(0) != nullptr &&
1136 phase->is_dominator(u->in(0), ctrl)) {
1137 const Type* u_t = phase->igvn().type(u);
1138
1139 if (u_t->meet(TypePtr::NULL_PTR) != u_t &&
1140 u->in(0)->Opcode() == Op_IfTrue &&
1141 u->in(0)->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) &&
1142 u->in(0)->in(0)->is_If() &&
1143 u->in(0)->in(0)->in(1)->Opcode() == Op_Bool &&
1144 u->in(0)->in(0)->in(1)->as_Bool()->_test._test == BoolTest::ne &&
1145 u->in(0)->in(0)->in(1)->in(1)->Opcode() == Op_CmpP &&
1146 u->in(0)->in(0)->in(1)->in(1)->in(1) == val &&
1147 u->in(0)->in(0)->in(1)->in(1)->in(2)->bottom_type() == TypePtr::NULL_PTR) {
1148 IdealLoopTree* loop = phase->get_loop(ctrl);
1149 IdealLoopTree* unc_loop = phase->get_loop(u->in(0));
1150
1151 if (!unc_loop->is_member(loop)) {
1152 continue;
1153 }
1154
1155 Node* branch = no_branches(ctrl, u->in(0), false, phase);
1156 assert(branch == nullptr || branch == NodeSentinel, "was not looking for a branch");
1157 if (branch == NodeSentinel) {
1158 continue;
1159 }
1160
1161 Node* iff = u->in(0)->in(0);
1162 Node* bol = iff->in(1)->clone();
1163 Node* cmp = bol->in(1)->clone();
1164 cmp->set_req(1, lrb);
1165 bol->set_req(1, cmp);
1166 phase->igvn().replace_input_of(iff, 1, bol);
1167 phase->set_ctrl(lrb, iff->in(0));
1168 phase->register_new_node(cmp, iff->in(0));
1169 phase->register_new_node(bol, iff->in(0));
1170 break;
1171 }
1172 }
1173 }
1174 if ((ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) || ctrl->is_CallJava()) {
1175 CallNode* call = ctrl->is_Proj() ? ctrl->in(0)->as_CallJava() : ctrl->as_CallJava();
1176 if (call->entry_point() == OptoRuntime::rethrow_stub()) {
1177 // The rethrow call may have too many projections to be
1178 // properly handled here. Given there's no reason for a
1179 // barrier to depend on the call, move it above the call
1180 stack.push(lrb, 0);
1181 do {
1182 Node* n = stack.node();
1183 uint idx = stack.index();
1184 if (idx < n->req()) {
1185 Node* in = n->in(idx);
1186 stack.set_index(idx+1);
1187 if (in != nullptr) {
1188 if (phase->has_ctrl(in)) {
1189 if (phase->is_dominator(call, phase->get_ctrl(in))) {
1190 #ifdef ASSERT
1191 for (uint i = 0; i < stack.size(); i++) {
1192 assert(stack.node_at(i) != in, "node shouldn't have been seen yet");
1193 }
1194 #endif
1195 stack.push(in, 0);
1196 }
1197 } else {
1198 assert(phase->is_dominator(in, call->in(0)), "no dependency on the call");
1199 }
1200 }
1201 } else {
1202 phase->set_ctrl(n, call->in(0));
1203 stack.pop();
1204 }
1205 } while(stack.size() > 0);
1206 continue;
1207 }
1208 CallProjections projs;
1209 call->extract_projections(&projs, false, false);
1210
1211 #ifdef ASSERT
1212 VectorSet cloned;
1213 #endif
1214 Node* lrb_clone = lrb->clone();
1215 phase->register_new_node(lrb_clone, projs.catchall_catchproj);
1216 phase->set_ctrl(lrb, projs.fallthrough_catchproj);
1217
1218 stack.push(lrb, 0);
1219 clones.push(lrb_clone);
1220
1221 do {
1222 assert(stack.size() == clones.size(), "");
1223 Node* n = stack.node();
1224 #ifdef ASSERT
1225 if (n->is_Load()) {
1226 Node* mem = n->in(MemNode::Memory);
1227 for (DUIterator_Fast jmax, j = mem->fast_outs(jmax); j < jmax; j++) {
1228 Node* u = mem->fast_out(j);
1229 assert(!u->is_Store() || !u->is_LoadStore() || phase->get_ctrl(u) != ctrl, "anti dependent store?");
1230 }
1231 }
1232 #endif
1233 uint idx = stack.index();
1234 Node* n_clone = clones.at(clones.size()-1);
1235 if (idx < n->outcnt()) {
1236 Node* u = n->raw_out(idx);
1237 Node* c = phase->ctrl_or_self(u);
1238 if (phase->is_dominator(call, c) && phase->is_dominator(c, projs.fallthrough_proj)) {
1239 stack.set_index(idx+1);
1240 assert(!u->is_CFG(), "");
1241 stack.push(u, 0);
1242 assert(!cloned.test_set(u->_idx), "only one clone");
1243 Node* u_clone = u->clone();
1244 int nb = u_clone->replace_edge(n, n_clone, &phase->igvn());
1245 assert(nb > 0, "should have replaced some uses");
1246 phase->register_new_node(u_clone, projs.catchall_catchproj);
1247 clones.push(u_clone);
1248 phase->set_ctrl(u, projs.fallthrough_catchproj);
1249 } else {
1250 bool replaced = false;
1251 if (u->is_Phi()) {
1252 for (uint k = 1; k < u->req(); k++) {
1253 if (u->in(k) == n) {
1254 if (phase->is_dominator(projs.catchall_catchproj, u->in(0)->in(k))) {
1255 phase->igvn().replace_input_of(u, k, n_clone);
1256 replaced = true;
1257 } else if (!phase->is_dominator(projs.fallthrough_catchproj, u->in(0)->in(k))) {
1258 phase->igvn().replace_input_of(u, k, create_phis_on_call_return(ctrl, u->in(0)->in(k), n, n_clone, projs, phase));
1259 replaced = true;
1260 }
1261 }
1262 }
1263 } else {
1264 if (phase->is_dominator(projs.catchall_catchproj, c)) {
1265 phase->igvn().rehash_node_delayed(u);
1266 int nb = u->replace_edge(n, n_clone, &phase->igvn());
1267 assert(nb > 0, "should have replaced some uses");
1268 replaced = true;
1269 } else if (!phase->is_dominator(projs.fallthrough_catchproj, c)) {
1270 if (u->is_If()) {
1271 // Can't break If/Bool/Cmp chain
1272 assert(n->is_Bool(), "unexpected If shape");
1273 assert(stack.node_at(stack.size()-2)->is_Cmp(), "unexpected If shape");
1274 assert(n_clone->is_Bool(), "unexpected clone");
1275 assert(clones.at(clones.size()-2)->is_Cmp(), "unexpected clone");
1276 Node* bol_clone = n->clone();
1277 Node* cmp_clone = stack.node_at(stack.size()-2)->clone();
1278 bol_clone->set_req(1, cmp_clone);
1279
1280 Node* nn = stack.node_at(stack.size()-3);
1281 Node* nn_clone = clones.at(clones.size()-3);
1282 assert(nn->Opcode() == nn_clone->Opcode(), "mismatch");
1283
1284 int nb = cmp_clone->replace_edge(nn, create_phis_on_call_return(ctrl, c, nn, nn_clone, projs, phase),
1285 &phase->igvn());
1286 assert(nb > 0, "should have replaced some uses");
1287
1288 phase->register_new_node(bol_clone, u->in(0));
1289 phase->register_new_node(cmp_clone, u->in(0));
1290
1291 phase->igvn().replace_input_of(u, 1, bol_clone);
1292
1293 } else {
1294 phase->igvn().rehash_node_delayed(u);
1295 int nb = u->replace_edge(n, create_phis_on_call_return(ctrl, c, n, n_clone, projs, phase), &phase->igvn());
1296 assert(nb > 0, "should have replaced some uses");
1297 }
1298 replaced = true;
1299 }
1300 }
1301 if (!replaced) {
1302 stack.set_index(idx+1);
1303 }
1304 }
1305 } else {
1306 stack.pop();
1307 clones.pop();
1308 }
1309 } while (stack.size() > 0);
1310 assert(stack.size() == 0 && clones.size() == 0, "");
1311 }
1312 }
1313
1314 for (int i = 0; i < state->load_reference_barriers_count(); i++) {
1315 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1316 Node* ctrl = phase->get_ctrl(lrb);
1317 IdealLoopTree* loop = phase->get_loop(ctrl);
1318 Node* head = loop->head();
1319 if (head->is_OuterStripMinedLoop()) {
1320 // Expanding a barrier here will break loop strip mining
1321 // verification. Transform the loop so the loop nest doesn't
1322 // appear as strip mined.
1323 OuterStripMinedLoopNode* outer = head->as_OuterStripMinedLoop();
1324 hide_strip_mined_loop(outer, outer->unique_ctrl_out()->as_CountedLoop(), phase);
1325 }
1326 }
1327
1328 // Expand load-reference-barriers
1329 MemoryGraphFixer fixer(Compile::AliasIdxRaw, true, phase);
1330 Unique_Node_List uses_to_ignore;
1331 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1332 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1333 uint last = phase->C->unique();
1334 Node* ctrl = phase->get_ctrl(lrb);
1335 Node* val = lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
1336
1337 Node* orig_ctrl = ctrl;
1338
1339 Node* raw_mem = fixer.find_mem(ctrl, lrb);
1340 Node* raw_mem_for_ctrl = fixer.find_mem(ctrl, nullptr);
1341
1342 IdealLoopTree *loop = phase->get_loop(ctrl);
1343
1344 Node* heap_stable_ctrl = nullptr;
1345 Node* null_ctrl = nullptr;
1346
1347 assert(val->bottom_type()->make_oopptr(), "need oop");
1348 assert(val->bottom_type()->make_oopptr()->const_oop() == nullptr, "expect non-constant");
1349
1350 enum { _heap_stable = 1, _evac_path, _not_cset, PATH_LIMIT };
1351 Node* region = new RegionNode(PATH_LIMIT);
1352 Node* val_phi = new PhiNode(region, val->bottom_type()->is_oopptr());
1353
1354 // Stable path.
1355 int flags = ShenandoahHeap::HAS_FORWARDED;
1356 if (!ShenandoahBarrierSet::is_strong_access(lrb->decorators())) {
1357 flags |= ShenandoahHeap::WEAK_ROOTS;
1358 }
1359 test_gc_state(ctrl, raw_mem, heap_stable_ctrl, phase, flags);
1360 IfNode* heap_stable_iff = heap_stable_ctrl->in(0)->as_If();
1361
1362 // Heap stable case
1363 region->init_req(_heap_stable, heap_stable_ctrl);
1364 val_phi->init_req(_heap_stable, val);
1365
1366 // Test for in-cset, unless it's a native-LRB. Native LRBs need to return null
1367 // even for non-cset objects to prevent resurrection of such objects.
1368 // Wires !in_cset(obj) to slot 2 of region and phis
1369 Node* not_cset_ctrl = nullptr;
1370 if (ShenandoahBarrierSet::is_strong_access(lrb->decorators())) {
1371 test_in_cset(ctrl, not_cset_ctrl, val, raw_mem, phase);
1372 }
1373 if (not_cset_ctrl != nullptr) {
1374 region->init_req(_not_cset, not_cset_ctrl);
1375 val_phi->init_req(_not_cset, val);
1376 } else {
1377 region->del_req(_not_cset);
1378 val_phi->del_req(_not_cset);
1379 }
1380
1381 // Resolve object when orig-value is in cset.
1382 // Make the unconditional resolve for fwdptr.
1383
1384 // Call lrb-stub and wire up that path in slots 4
1385 Node* result_mem = nullptr;
1386
1387 Node* addr;
1388 if (ShenandoahSelfFixing) {
1389 VectorSet visited;
1390 addr = get_load_addr(phase, visited, lrb);
1391 } else {
1392 addr = phase->igvn().zerocon(T_OBJECT);
1393 }
1394 if (addr->Opcode() == Op_AddP) {
1395 Node* orig_base = addr->in(AddPNode::Base);
1396 Node* base = new CheckCastPPNode(ctrl, orig_base, orig_base->bottom_type(), ConstraintCastNode::StrongDependency);
1397 phase->register_new_node(base, ctrl);
1398 if (addr->in(AddPNode::Base) == addr->in((AddPNode::Address))) {
1399 // Field access
1400 addr = addr->clone();
1401 addr->set_req(AddPNode::Base, base);
1402 addr->set_req(AddPNode::Address, base);
1403 phase->register_new_node(addr, ctrl);
1404 } else {
1405 Node* addr2 = addr->in(AddPNode::Address);
1406 if (addr2->Opcode() == Op_AddP && addr2->in(AddPNode::Base) == addr2->in(AddPNode::Address) &&
1407 addr2->in(AddPNode::Base) == orig_base) {
1408 addr2 = addr2->clone();
1409 addr2->set_req(AddPNode::Base, base);
1410 addr2->set_req(AddPNode::Address, base);
1411 phase->register_new_node(addr2, ctrl);
1412 addr = addr->clone();
1413 addr->set_req(AddPNode::Base, base);
1414 addr->set_req(AddPNode::Address, addr2);
1415 phase->register_new_node(addr, ctrl);
1416 }
1417 }
1418 }
1419 call_lrb_stub(ctrl, val, addr, lrb->decorators(), phase);
1420 region->init_req(_evac_path, ctrl);
1421 val_phi->init_req(_evac_path, val);
1422
1423 phase->register_control(region, loop, heap_stable_iff);
1424 Node* out_val = val_phi;
1425 phase->register_new_node(val_phi, region);
1426
1427 fix_ctrl(lrb, region, fixer, uses, uses_to_ignore, last, phase);
1428
1429 ctrl = orig_ctrl;
1430
1431 phase->igvn().replace_node(lrb, out_val);
1432
1433 follow_barrier_uses(out_val, ctrl, uses, phase);
1434
1435 for(uint next = 0; next < uses.size(); next++ ) {
1436 Node *n = uses.at(next);
1437 assert(phase->get_ctrl(n) == ctrl, "bad control");
1438 assert(n != raw_mem, "should leave input raw mem above the barrier");
1439 phase->set_ctrl(n, region);
1440 follow_barrier_uses(n, ctrl, uses, phase);
1441 }
1442 fixer.record_new_ctrl(ctrl, region, raw_mem, raw_mem_for_ctrl);
1443 }
1444 // Done expanding load-reference-barriers.
1445 assert(ShenandoahBarrierSetC2::bsc2()->state()->load_reference_barriers_count() == 0, "all load reference barrier nodes should have been replaced");
1446
1447 for (int i = state->iu_barriers_count() - 1; i >= 0; i--) {
1448 Node* barrier = state->iu_barrier(i);
1449 Node* pre_val = barrier->in(1);
1450
1451 if (phase->igvn().type(pre_val)->higher_equal(TypePtr::NULL_PTR)) {
1452 ShouldNotReachHere();
1453 continue;
1454 }
1455
1456 Node* ctrl = phase->get_ctrl(barrier);
1457
1458 if (ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) {
1459 assert(is_dominator(phase->get_ctrl(pre_val), ctrl->in(0)->in(0), pre_val, ctrl->in(0), phase), "can't move");
1460 ctrl = ctrl->in(0)->in(0);
1461 phase->set_ctrl(barrier, ctrl);
1462 } else if (ctrl->is_CallRuntime()) {
1463 assert(is_dominator(phase->get_ctrl(pre_val), ctrl->in(0), pre_val, ctrl, phase), "can't move");
1464 ctrl = ctrl->in(0);
1465 phase->set_ctrl(barrier, ctrl);
1466 }
1467
1468 Node* init_ctrl = ctrl;
1469 IdealLoopTree* loop = phase->get_loop(ctrl);
1470 Node* raw_mem = fixer.find_mem(ctrl, barrier);
1471 Node* init_raw_mem = raw_mem;
1472 Node* raw_mem_for_ctrl = fixer.find_mem(ctrl, nullptr);
1473 Node* heap_stable_ctrl = nullptr;
1474 Node* null_ctrl = nullptr;
1475 uint last = phase->C->unique();
1476
1477 enum { _heap_stable = 1, _heap_unstable, PATH_LIMIT };
1478 Node* region = new RegionNode(PATH_LIMIT);
1479 Node* phi = PhiNode::make(region, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
1480
1481 enum { _fast_path = 1, _slow_path, _null_path, PATH_LIMIT2 };
1482 Node* region2 = new RegionNode(PATH_LIMIT2);
1483 Node* phi2 = PhiNode::make(region2, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
1484
1485 // Stable path.
1486 test_gc_state(ctrl, raw_mem, heap_stable_ctrl, phase, (ShenandoahHeap::YOUNG_MARKING | ShenandoahHeap::OLD_MARKING));
1487 region->init_req(_heap_stable, heap_stable_ctrl);
1488 phi->init_req(_heap_stable, raw_mem);
1489
1490 // Null path
1491 Node* reg2_ctrl = nullptr;
1492 test_null(ctrl, pre_val, null_ctrl, phase);
1493 if (null_ctrl != nullptr) {
1494 reg2_ctrl = null_ctrl->in(0);
1495 region2->init_req(_null_path, null_ctrl);
1496 phi2->init_req(_null_path, raw_mem);
1497 } else {
1498 region2->del_req(_null_path);
1499 phi2->del_req(_null_path);
1500 }
1501
1502 const int index_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset());
1503 const int buffer_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset());
1504 Node* thread = new ThreadLocalNode();
1505 phase->register_new_node(thread, ctrl);
1506 Node* buffer_adr = new AddPNode(phase->C->top(), thread, phase->igvn().MakeConX(buffer_offset));
1507 phase->register_new_node(buffer_adr, ctrl);
1508 Node* index_adr = new AddPNode(phase->C->top(), thread, phase->igvn().MakeConX(index_offset));
1509 phase->register_new_node(index_adr, ctrl);
1510
1511 BasicType index_bt = TypeX_X->basic_type();
1512 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading Shenandoah SATBMarkQueue::_index with wrong size.");
1513 const TypePtr* adr_type = TypeRawPtr::BOTTOM;
1514 Node* index = new LoadXNode(ctrl, raw_mem, index_adr, adr_type, TypeX_X, MemNode::unordered);
1515 phase->register_new_node(index, ctrl);
1516 Node* index_cmp = new CmpXNode(index, phase->igvn().MakeConX(0));
1517 phase->register_new_node(index_cmp, ctrl);
1518 Node* index_test = new BoolNode(index_cmp, BoolTest::ne);
1519 phase->register_new_node(index_test, ctrl);
1520 IfNode* queue_full_iff = new IfNode(ctrl, index_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
1521 if (reg2_ctrl == nullptr) reg2_ctrl = queue_full_iff;
1522 phase->register_control(queue_full_iff, loop, ctrl);
1523 Node* not_full = new IfTrueNode(queue_full_iff);
1524 phase->register_control(not_full, loop, queue_full_iff);
1525 Node* full = new IfFalseNode(queue_full_iff);
1526 phase->register_control(full, loop, queue_full_iff);
1527
1528 ctrl = not_full;
1529
1530 Node* next_index = new SubXNode(index, phase->igvn().MakeConX(sizeof(intptr_t)));
1531 phase->register_new_node(next_index, ctrl);
1532
1533 Node* buffer = new LoadPNode(ctrl, raw_mem, buffer_adr, adr_type, TypeRawPtr::NOTNULL, MemNode::unordered);
1534 phase->register_new_node(buffer, ctrl);
1535 Node *log_addr = new AddPNode(phase->C->top(), buffer, next_index);
1536 phase->register_new_node(log_addr, ctrl);
1537 Node* log_store = new StorePNode(ctrl, raw_mem, log_addr, adr_type, pre_val, MemNode::unordered);
1538 phase->register_new_node(log_store, ctrl);
1539 // update the index
1540 Node* index_update = new StoreXNode(ctrl, log_store, index_adr, adr_type, next_index, MemNode::unordered);
1541 phase->register_new_node(index_update, ctrl);
1542
1543 // Fast-path case
1544 region2->init_req(_fast_path, ctrl);
1545 phi2->init_req(_fast_path, index_update);
1546
1547 ctrl = full;
1548
1549 Node* base = find_bottom_mem(ctrl, phase);
1550
1551 MergeMemNode* mm = MergeMemNode::make(base);
1552 mm->set_memory_at(Compile::AliasIdxRaw, raw_mem);
1553 phase->register_new_node(mm, ctrl);
1554
1555 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);
1556 call->init_req(TypeFunc::Control, ctrl);
1557 call->init_req(TypeFunc::I_O, phase->C->top());
1558 call->init_req(TypeFunc::Memory, mm);
1559 call->init_req(TypeFunc::FramePtr, phase->C->top());
1560 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
1561 call->init_req(TypeFunc::Parms, pre_val);
1562 call->init_req(TypeFunc::Parms+1, thread);
1563 phase->register_control(call, loop, ctrl);
1564
1565 Node* ctrl_proj = new ProjNode(call, TypeFunc::Control);
1566 phase->register_control(ctrl_proj, loop, call);
1567 Node* mem_proj = new ProjNode(call, TypeFunc::Memory);
1568 phase->register_new_node(mem_proj, call);
1569
1570 // Slow-path case
1571 region2->init_req(_slow_path, ctrl_proj);
1572 phi2->init_req(_slow_path, mem_proj);
1573
1574 phase->register_control(region2, loop, reg2_ctrl);
1575 phase->register_new_node(phi2, region2);
1576
1577 region->init_req(_heap_unstable, region2);
1578 phi->init_req(_heap_unstable, phi2);
1579
1580 phase->register_control(region, loop, heap_stable_ctrl->in(0));
1581 phase->register_new_node(phi, region);
1582
1583 fix_ctrl(barrier, region, fixer, uses, uses_to_ignore, last, phase);
1584 for(uint next = 0; next < uses.size(); next++ ) {
1585 Node *n = uses.at(next);
1586 assert(phase->get_ctrl(n) == init_ctrl, "bad control");
1587 assert(n != init_raw_mem, "should leave input raw mem above the barrier");
1588 phase->set_ctrl(n, region);
1589 follow_barrier_uses(n, init_ctrl, uses, phase);
1590 }
1591 fixer.fix_mem(init_ctrl, region, init_raw_mem, raw_mem_for_ctrl, phi, uses);
1592
1593 phase->igvn().replace_node(barrier, pre_val);
1594 }
1595 assert(state->iu_barriers_count() == 0, "all enqueue barrier nodes should have been replaced");
1596
1597 }
1598
1599 Node* ShenandoahBarrierC2Support::get_load_addr(PhaseIdealLoop* phase, VectorSet& visited, Node* in) {
1600 if (visited.test_set(in->_idx)) {
1601 return nullptr;
1602 }
1603 switch (in->Opcode()) {
1604 case Op_Proj:
1605 return get_load_addr(phase, visited, in->in(0));
1606 case Op_CastPP:
1607 case Op_CheckCastPP:
1608 case Op_DecodeN:
1609 case Op_EncodeP:
1610 return get_load_addr(phase, visited, in->in(1));
1611 case Op_LoadN:
1612 case Op_LoadP:
1613 return in->in(MemNode::Address);
1614 case Op_CompareAndExchangeN:
1615 case Op_CompareAndExchangeP:
1616 case Op_GetAndSetN:
1617 case Op_GetAndSetP:
1618 case Op_ShenandoahCompareAndExchangeP:
1619 case Op_ShenandoahCompareAndExchangeN:
1620 // Those instructions would just have stored a different
1621 // value into the field. No use to attempt to fix it at this point.
1622 return phase->igvn().zerocon(T_OBJECT);
1623 case Op_CMoveP:
1624 case Op_CMoveN: {
1625 Node* t = get_load_addr(phase, visited, in->in(CMoveNode::IfTrue));
1626 Node* f = get_load_addr(phase, visited, in->in(CMoveNode::IfFalse));
1627 // Handle unambiguous cases: single address reported on both branches.
1628 if (t != nullptr && f == nullptr) return t;
1629 if (t == nullptr && f != nullptr) return f;
1630 if (t != nullptr && t == f) return t;
1631 // Ambiguity.
1632 return phase->igvn().zerocon(T_OBJECT);
1633 }
1634 case Op_Phi: {
1635 Node* addr = nullptr;
1636 for (uint i = 1; i < in->req(); i++) {
1637 Node* addr1 = get_load_addr(phase, visited, in->in(i));
1638 if (addr == nullptr) {
1639 addr = addr1;
1640 }
1641 if (addr != addr1) {
1642 return phase->igvn().zerocon(T_OBJECT);
1643 }
1644 }
1645 return addr;
1646 }
1647 case Op_ShenandoahLoadReferenceBarrier:
1648 return get_load_addr(phase, visited, in->in(ShenandoahLoadReferenceBarrierNode::ValueIn));
1649 case Op_ShenandoahIUBarrier:
1650 return get_load_addr(phase, visited, in->in(1));
1651 case Op_CallDynamicJava:
1652 case Op_CallLeaf:
1653 case Op_CallStaticJava:
1654 case Op_ConN:
1655 case Op_ConP:
1656 case Op_Parm:
1657 case Op_CreateEx:
1658 return phase->igvn().zerocon(T_OBJECT);
1659 default:
1660 #ifdef ASSERT
1661 fatal("Unknown node in get_load_addr: %s", NodeClassNames[in->Opcode()]);
1662 #endif
1663 return phase->igvn().zerocon(T_OBJECT);
1664 }
1665
1666 }
1667
1668 void ShenandoahBarrierC2Support::move_gc_state_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase) {
1669 IdealLoopTree *loop = phase->get_loop(iff);
1670 Node* loop_head = loop->_head;
1671 Node* entry_c = loop_head->in(LoopNode::EntryControl);
1672
1673 Node* bol = iff->in(1);
1674 Node* cmp = bol->in(1);
1675 Node* andi = cmp->in(1);
1676 Node* load = andi->in(1);
1677
1678 assert(is_gc_state_load(load), "broken");
1679 if (!phase->is_dominator(load->in(0), entry_c)) {
1680 Node* mem_ctrl = nullptr;
1681 Node* mem = dom_mem(load->in(MemNode::Memory), loop_head, Compile::AliasIdxRaw, mem_ctrl, phase);
1682 load = load->clone();
1683 load->set_req(MemNode::Memory, mem);
1684 load->set_req(0, entry_c);
1685 phase->register_new_node(load, entry_c);
1686 andi = andi->clone();
1687 andi->set_req(1, load);
1688 phase->register_new_node(andi, entry_c);
1689 cmp = cmp->clone();
1690 cmp->set_req(1, andi);
1691 phase->register_new_node(cmp, entry_c);
1692 bol = bol->clone();
1693 bol->set_req(1, cmp);
1694 phase->register_new_node(bol, entry_c);
1695
1696 phase->igvn().replace_input_of(iff, 1, bol);
1697 }
1698 }
1699
1700 bool ShenandoahBarrierC2Support::identical_backtoback_ifs(Node* n, PhaseIdealLoop* phase) {
1701 if (!n->is_If() || n->is_CountedLoopEnd()) {
1702 return false;
1703 }
1704 Node* region = n->in(0);
1705
1706 if (!region->is_Region()) {
1707 return false;
1708 }
1709 Node* dom = phase->idom(region);
1710 if (!dom->is_If()) {
1711 return false;
1712 }
1713
1714 if (!is_heap_stable_test(n) || !is_heap_stable_test(dom)) {
1715 return false;
1716 }
1717
1718 IfNode* dom_if = dom->as_If();
1719 Node* proj_true = dom_if->proj_out(1);
1720 Node* proj_false = dom_if->proj_out(0);
1721
1722 for (uint i = 1; i < region->req(); i++) {
1723 if (phase->is_dominator(proj_true, region->in(i))) {
1724 continue;
1725 }
1726 if (phase->is_dominator(proj_false, region->in(i))) {
1727 continue;
1728 }
1729 return false;
1730 }
1731
1732 return true;
1733 }
1734
1735 void ShenandoahBarrierC2Support::merge_back_to_back_tests(Node* n, PhaseIdealLoop* phase) {
1736 assert(is_heap_stable_test(n), "no other tests");
1737 if (identical_backtoback_ifs(n, phase)) {
1738 Node* n_ctrl = n->in(0);
1739 if (phase->can_split_if(n_ctrl)) {
1740 IfNode* dom_if = phase->idom(n_ctrl)->as_If();
1741 if (is_heap_stable_test(n)) {
1742 Node* gc_state_load = n->in(1)->in(1)->in(1)->in(1);
1743 assert(is_gc_state_load(gc_state_load), "broken");
1744 Node* dom_gc_state_load = dom_if->in(1)->in(1)->in(1)->in(1);
1745 assert(is_gc_state_load(dom_gc_state_load), "broken");
1746 if (gc_state_load != dom_gc_state_load) {
1747 phase->igvn().replace_node(gc_state_load, dom_gc_state_load);
1748 }
1749 }
1750 PhiNode* bolphi = PhiNode::make_blank(n_ctrl, n->in(1));
1751 Node* proj_true = dom_if->proj_out(1);
1752 Node* proj_false = dom_if->proj_out(0);
1753 Node* con_true = phase->igvn().makecon(TypeInt::ONE);
1754 Node* con_false = phase->igvn().makecon(TypeInt::ZERO);
1755
1756 for (uint i = 1; i < n_ctrl->req(); i++) {
1757 if (phase->is_dominator(proj_true, n_ctrl->in(i))) {
1758 bolphi->init_req(i, con_true);
1759 } else {
1760 assert(phase->is_dominator(proj_false, n_ctrl->in(i)), "bad if");
1761 bolphi->init_req(i, con_false);
1762 }
1763 }
1764 phase->register_new_node(bolphi, n_ctrl);
1765 phase->igvn().replace_input_of(n, 1, bolphi);
1766 phase->do_split_if(n);
1767 }
1768 }
1769 }
1770
1771 IfNode* ShenandoahBarrierC2Support::find_unswitching_candidate(const IdealLoopTree* loop, PhaseIdealLoop* phase) {
1772 // Find first invariant test that doesn't exit the loop
1773 LoopNode *head = loop->_head->as_Loop();
1774 IfNode* unswitch_iff = nullptr;
1775 Node* n = head->in(LoopNode::LoopBackControl);
1776 int loop_has_sfpts = -1;
1777 while (n != head) {
1778 Node* n_dom = phase->idom(n);
1779 if (n->is_Region()) {
1780 if (n_dom->is_If()) {
1781 IfNode* iff = n_dom->as_If();
1782 if (iff->in(1)->is_Bool()) {
1783 BoolNode* bol = iff->in(1)->as_Bool();
1784 if (bol->in(1)->is_Cmp()) {
1785 // If condition is invariant and not a loop exit,
1786 // then found reason to unswitch.
1787 if (is_heap_stable_test(iff) &&
1788 (loop_has_sfpts == -1 || loop_has_sfpts == 0)) {
1789 assert(!loop->is_loop_exit(iff), "both branches should be in the loop");
1790 if (loop_has_sfpts == -1) {
1791 for(uint i = 0; i < loop->_body.size(); i++) {
1792 Node *m = loop->_body[i];
1793 if (m->is_SafePoint() && !m->is_CallLeaf()) {
1794 loop_has_sfpts = 1;
1795 break;
1796 }
1797 }
1798 if (loop_has_sfpts == -1) {
1799 loop_has_sfpts = 0;
1800 }
1801 }
1802 if (!loop_has_sfpts) {
1803 unswitch_iff = iff;
1804 }
1805 }
1806 }
1807 }
1808 }
1809 }
1810 n = n_dom;
1811 }
1812 return unswitch_iff;
1813 }
1814
1815
1816 void ShenandoahBarrierC2Support::optimize_after_expansion(VectorSet &visited, Node_Stack &stack, Node_List &old_new, PhaseIdealLoop* phase) {
1817 Node_List heap_stable_tests;
1818 stack.push(phase->C->start(), 0);
1819 do {
1820 Node* n = stack.node();
1821 uint i = stack.index();
1822
1823 if (i < n->outcnt()) {
1824 Node* u = n->raw_out(i);
1825 stack.set_index(i+1);
1826 if (!visited.test_set(u->_idx)) {
1827 stack.push(u, 0);
1828 }
1829 } else {
1830 stack.pop();
1831 if (n->is_If() && is_heap_stable_test(n)) {
1832 heap_stable_tests.push(n);
1833 }
1834 }
1835 } while (stack.size() > 0);
1836
1837 for (uint i = 0; i < heap_stable_tests.size(); i++) {
1838 Node* n = heap_stable_tests.at(i);
1839 assert(is_heap_stable_test(n), "only evacuation test");
1840 merge_back_to_back_tests(n, phase);
1841 }
1842
1843 if (!phase->C->major_progress()) {
1844 VectorSet seen;
1845 for (uint i = 0; i < heap_stable_tests.size(); i++) {
1846 Node* n = heap_stable_tests.at(i);
1847 IdealLoopTree* loop = phase->get_loop(n);
1848 if (loop != phase->ltree_root() &&
1849 loop->_child == nullptr &&
1850 !loop->_irreducible) {
1851 Node* head = loop->_head;
1852 if (head->is_Loop() &&
1853 (!head->is_CountedLoop() || head->as_CountedLoop()->is_main_loop() || head->as_CountedLoop()->is_normal_loop()) &&
1854 !seen.test_set(head->_idx)) {
1855 IfNode* iff = find_unswitching_candidate(loop, phase);
1856 if (iff != nullptr) {
1857 Node* bol = iff->in(1);
1858 if (head->as_Loop()->is_strip_mined()) {
1859 head->as_Loop()->verify_strip_mined(0);
1860 }
1861 move_gc_state_test_out_of_loop(iff, phase);
1862
1863 AutoNodeBudget node_budget(phase);
1864
1865 if (loop->policy_unswitching(phase)) {
1866 if (head->as_Loop()->is_strip_mined()) {
1867 OuterStripMinedLoopNode* outer = head->as_CountedLoop()->outer_loop();
1868 hide_strip_mined_loop(outer, head->as_CountedLoop(), phase);
1869 }
1870 phase->do_unswitching(loop, old_new);
1871 } else {
1872 // Not proceeding with unswitching. Move load back in
1873 // the loop.
1874 phase->igvn().replace_input_of(iff, 1, bol);
1875 }
1876 }
1877 }
1878 }
1879 }
1880 }
1881 }
1882
1883 ShenandoahIUBarrierNode::ShenandoahIUBarrierNode(Node* val) : Node(nullptr, val) {
1884 ShenandoahBarrierSetC2::bsc2()->state()->add_iu_barrier(this);
1885 }
1886
1887 const Type* ShenandoahIUBarrierNode::bottom_type() const {
1888 if (in(1) == nullptr || in(1)->is_top()) {
1889 return Type::TOP;
1890 }
1891 const Type* t = in(1)->bottom_type();
1892 if (t == TypePtr::NULL_PTR) {
1893 return t;
1894 }
1895 return t->is_oopptr();
1896 }
1897
1898 const Type* ShenandoahIUBarrierNode::Value(PhaseGVN* phase) const {
1899 if (in(1) == nullptr) {
1900 return Type::TOP;
1901 }
1902 const Type* t = phase->type(in(1));
1903 if (t == Type::TOP) {
1904 return Type::TOP;
1905 }
1906 if (t == TypePtr::NULL_PTR) {
1907 return t;
1908 }
1909 return t->is_oopptr();
1910 }
1911
1912 int ShenandoahIUBarrierNode::needed(Node* n) {
1913 if (n == nullptr ||
1914 n->is_Allocate() ||
1915 n->Opcode() == Op_ShenandoahIUBarrier ||
1916 n->bottom_type() == TypePtr::NULL_PTR ||
1917 (n->bottom_type()->make_oopptr() != nullptr && n->bottom_type()->make_oopptr()->const_oop() != nullptr)) {
1918 return NotNeeded;
1919 }
1920 if (n->is_Phi() ||
1921 n->is_CMove()) {
1922 return MaybeNeeded;
1923 }
1924 return Needed;
1925 }
1926
1927 Node* ShenandoahIUBarrierNode::next(Node* n) {
1928 for (;;) {
1929 if (n == nullptr) {
1930 return n;
1931 } else if (n->bottom_type() == TypePtr::NULL_PTR) {
1932 return n;
1933 } else if (n->bottom_type()->make_oopptr() != nullptr && n->bottom_type()->make_oopptr()->const_oop() != nullptr) {
1934 return n;
1935 } else if (n->is_ConstraintCast() ||
1936 n->Opcode() == Op_DecodeN ||
1937 n->Opcode() == Op_EncodeP) {
1938 n = n->in(1);
1939 } else if (n->is_Proj()) {
1940 n = n->in(0);
1941 } else {
1942 return n;
1943 }
1944 }
1945 ShouldNotReachHere();
1946 return nullptr;
1947 }
1948
1949 Node* ShenandoahIUBarrierNode::Identity(PhaseGVN* phase) {
1950 PhaseIterGVN* igvn = phase->is_IterGVN();
1951
1952 Node* n = next(in(1));
1953
1954 int cont = needed(n);
1955
1956 if (cont == NotNeeded) {
1957 return in(1);
1958 } else if (cont == MaybeNeeded) {
1959 if (igvn == nullptr) {
1960 phase->record_for_igvn(this);
1961 return this;
1962 } else {
1963 ResourceMark rm;
1964 Unique_Node_List wq;
1965 uint wq_i = 0;
1966
1967 for (;;) {
1968 if (n->is_Phi()) {
1969 for (uint i = 1; i < n->req(); i++) {
1970 Node* m = n->in(i);
1971 if (m != nullptr) {
1972 wq.push(m);
1973 }
1974 }
1975 } else {
1976 assert(n->is_CMove(), "nothing else here");
1977 Node* m = n->in(CMoveNode::IfFalse);
1978 wq.push(m);
1979 m = n->in(CMoveNode::IfTrue);
1980 wq.push(m);
1981 }
1982 Node* orig_n = nullptr;
1983 do {
1984 if (wq_i >= wq.size()) {
1985 return in(1);
1986 }
1987 n = wq.at(wq_i);
1988 wq_i++;
1989 orig_n = n;
1990 n = next(n);
1991 cont = needed(n);
1992 if (cont == Needed) {
1993 return this;
1994 }
1995 } while (cont != MaybeNeeded || (orig_n != n && wq.member(n)));
1996 }
1997 }
1998 }
1999
2000 return this;
2001 }
2002
2003 #ifdef ASSERT
2004 static bool has_never_branch(Node* root) {
2005 for (uint i = 1; i < root->req(); i++) {
2006 Node* in = root->in(i);
2007 if (in != nullptr && in->Opcode() == Op_Halt && in->in(0)->is_Proj() && in->in(0)->in(0)->is_NeverBranch()) {
2008 return true;
2009 }
2010 }
2011 return false;
2012 }
2013 #endif
2014
2015 void MemoryGraphFixer::collect_memory_nodes() {
2016 Node_Stack stack(0);
2017 VectorSet visited;
2018 Node_List regions;
2019
2020 // Walk the raw memory graph and create a mapping from CFG node to
2021 // memory node. Exclude phis for now.
2022 stack.push(_phase->C->root(), 1);
2023 do {
2024 Node* n = stack.node();
2025 int opc = n->Opcode();
2026 uint i = stack.index();
2027 if (i < n->req()) {
2028 Node* mem = nullptr;
2029 if (opc == Op_Root) {
2030 Node* in = n->in(i);
2031 int in_opc = in->Opcode();
2032 if (in_opc == Op_Return || in_opc == Op_Rethrow) {
2033 mem = in->in(TypeFunc::Memory);
2034 } else if (in_opc == Op_Halt) {
2035 if (in->in(0)->is_Region()) {
2036 Node* r = in->in(0);
2037 for (uint j = 1; j < r->req(); j++) {
2038 assert(!r->in(j)->is_NeverBranch(), "");
2039 }
2040 } else {
2041 Node* proj = in->in(0);
2042 assert(proj->is_Proj(), "");
2043 Node* in = proj->in(0);
2044 assert(in->is_CallStaticJava() || in->is_NeverBranch() || in->Opcode() == Op_Catch || proj->is_IfProj(), "");
2045 if (in->is_CallStaticJava()) {
2046 mem = in->in(TypeFunc::Memory);
2047 } else if (in->Opcode() == Op_Catch) {
2048 Node* call = in->in(0)->in(0);
2049 assert(call->is_Call(), "");
2050 mem = call->in(TypeFunc::Memory);
2051 } else if (in->is_NeverBranch()) {
2052 mem = collect_memory_for_infinite_loop(in);
2053 }
2054 }
2055 } else {
2056 #ifdef ASSERT
2057 n->dump();
2058 in->dump();
2059 #endif
2060 ShouldNotReachHere();
2061 }
2062 } else {
2063 assert(n->is_Phi() && n->bottom_type() == Type::MEMORY, "");
2064 assert(n->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(n->adr_type()) == _alias, "");
2065 mem = n->in(i);
2066 }
2067 i++;
2068 stack.set_index(i);
2069 if (mem == nullptr) {
2070 continue;
2071 }
2072 for (;;) {
2073 if (visited.test_set(mem->_idx) || mem->is_Start()) {
2074 break;
2075 }
2076 if (mem->is_Phi()) {
2077 stack.push(mem, 2);
2078 mem = mem->in(1);
2079 } else if (mem->is_Proj()) {
2080 stack.push(mem, mem->req());
2081 mem = mem->in(0);
2082 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
2083 mem = mem->in(TypeFunc::Memory);
2084 } else if (mem->is_MergeMem()) {
2085 MergeMemNode* mm = mem->as_MergeMem();
2086 mem = mm->memory_at(_alias);
2087 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
2088 assert(_alias == Compile::AliasIdxRaw, "");
2089 stack.push(mem, mem->req());
2090 mem = mem->in(MemNode::Memory);
2091 } else {
2092 #ifdef ASSERT
2093 mem->dump();
2094 #endif
2095 ShouldNotReachHere();
2096 }
2097 }
2098 } else {
2099 if (n->is_Phi()) {
2100 // Nothing
2101 } else if (!n->is_Root()) {
2102 Node* c = get_ctrl(n);
2103 _memory_nodes.map(c->_idx, n);
2104 }
2105 stack.pop();
2106 }
2107 } while(stack.is_nonempty());
2108
2109 // Iterate over CFG nodes in rpo and propagate memory state to
2110 // compute memory state at regions, creating new phis if needed.
2111 Node_List rpo_list;
2112 visited.clear();
2113 _phase->rpo(_phase->C->root(), stack, visited, rpo_list);
2114 Node* root = rpo_list.pop();
2115 assert(root == _phase->C->root(), "");
2116
2117 const bool trace = false;
2118 #ifdef ASSERT
2119 if (trace) {
2120 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2121 Node* c = rpo_list.at(i);
2122 if (_memory_nodes[c->_idx] != nullptr) {
2123 tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump();
2124 }
2125 }
2126 }
2127 #endif
2128 uint last = _phase->C->unique();
2129
2130 #ifdef ASSERT
2131 uint16_t max_depth = 0;
2132 for (LoopTreeIterator iter(_phase->ltree_root()); !iter.done(); iter.next()) {
2133 IdealLoopTree* lpt = iter.current();
2134 max_depth = MAX2(max_depth, lpt->_nest);
2135 }
2136 #endif
2137
2138 bool progress = true;
2139 int iteration = 0;
2140 Node_List dead_phis;
2141 while (progress) {
2142 progress = false;
2143 iteration++;
2144 assert(iteration <= 2+max_depth || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "");
2145 if (trace) { tty->print_cr("XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"); }
2146
2147 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2148 Node* c = rpo_list.at(i);
2149
2150 Node* prev_mem = _memory_nodes[c->_idx];
2151 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2152 Node* prev_region = regions[c->_idx];
2153 Node* unique = nullptr;
2154 for (uint j = 1; j < c->req() && unique != NodeSentinel; j++) {
2155 Node* m = _memory_nodes[c->in(j)->_idx];
2156 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");
2157 if (m != nullptr) {
2158 if (m == prev_region && ((c->is_Loop() && j == LoopNode::LoopBackControl) || (prev_region->is_Phi() && prev_region->in(0) == c))) {
2159 assert(c->is_Loop() && j == LoopNode::LoopBackControl || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "");
2160 // continue
2161 } else if (unique == nullptr) {
2162 unique = m;
2163 } else if (m == unique) {
2164 // continue
2165 } else {
2166 unique = NodeSentinel;
2167 }
2168 }
2169 }
2170 assert(unique != nullptr, "empty phi???");
2171 if (unique != NodeSentinel) {
2172 if (prev_region != nullptr && prev_region->is_Phi() && prev_region->in(0) == c) {
2173 dead_phis.push(prev_region);
2174 }
2175 regions.map(c->_idx, unique);
2176 } else {
2177 Node* phi = nullptr;
2178 if (prev_region != nullptr && prev_region->is_Phi() && prev_region->in(0) == c && prev_region->_idx >= last) {
2179 phi = prev_region;
2180 for (uint k = 1; k < c->req(); k++) {
2181 Node* m = _memory_nodes[c->in(k)->_idx];
2182 assert(m != nullptr, "expect memory state");
2183 phi->set_req(k, m);
2184 }
2185 } else {
2186 for (DUIterator_Fast jmax, j = c->fast_outs(jmax); j < jmax && phi == nullptr; j++) {
2187 Node* u = c->fast_out(j);
2188 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2189 (u->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(u->adr_type()) == _alias)) {
2190 phi = u;
2191 for (uint k = 1; k < c->req() && phi != nullptr; k++) {
2192 Node* m = _memory_nodes[c->in(k)->_idx];
2193 assert(m != nullptr, "expect memory state");
2194 if (u->in(k) != m) {
2195 phi = NodeSentinel;
2196 }
2197 }
2198 }
2199 }
2200 if (phi == NodeSentinel) {
2201 phi = new PhiNode(c, Type::MEMORY, _phase->C->get_adr_type(_alias));
2202 for (uint k = 1; k < c->req(); k++) {
2203 Node* m = _memory_nodes[c->in(k)->_idx];
2204 assert(m != nullptr, "expect memory state");
2205 phi->init_req(k, m);
2206 }
2207 }
2208 }
2209 if (phi != nullptr) {
2210 regions.map(c->_idx, phi);
2211 } else {
2212 assert(c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
2213 }
2214 }
2215 Node* current_region = regions[c->_idx];
2216 if (current_region != prev_region) {
2217 progress = true;
2218 if (prev_region == prev_mem) {
2219 _memory_nodes.map(c->_idx, current_region);
2220 }
2221 }
2222 } else if (prev_mem == nullptr || prev_mem->is_Phi() || ctrl_or_self(prev_mem) != c) {
2223 Node* m = _memory_nodes[_phase->idom(c)->_idx];
2224 assert(m != nullptr || c->Opcode() == Op_Halt, "expect memory state");
2225 if (m != prev_mem) {
2226 _memory_nodes.map(c->_idx, m);
2227 progress = true;
2228 }
2229 }
2230 #ifdef ASSERT
2231 if (trace) { tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump(); }
2232 #endif
2233 }
2234 }
2235
2236 // Replace existing phi with computed memory state for that region
2237 // if different (could be a new phi or a dominating memory node if
2238 // that phi was found to be useless).
2239 while (dead_phis.size() > 0) {
2240 Node* n = dead_phis.pop();
2241 n->replace_by(_phase->C->top());
2242 n->destruct(&_phase->igvn());
2243 }
2244 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2245 Node* c = rpo_list.at(i);
2246 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2247 Node* n = regions[c->_idx];
2248 assert(n != nullptr || c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
2249 if (n != nullptr && n->is_Phi() && n->_idx >= last && n->in(0) == c) {
2250 _phase->register_new_node(n, c);
2251 }
2252 }
2253 }
2254 for (int i = rpo_list.size() - 1; i >= 0; i--) {
2255 Node* c = rpo_list.at(i);
2256 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
2257 Node* n = regions[c->_idx];
2258 assert(n != nullptr || c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
2259 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
2260 Node* u = c->fast_out(i);
2261 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2262 u != n) {
2263 assert(c->unique_ctrl_out()->Opcode() != Op_Halt, "expected memory state");
2264 if (u->adr_type() == TypePtr::BOTTOM) {
2265 fix_memory_uses(u, n, n, c);
2266 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2267 _phase->lazy_replace(u, n);
2268 --i; --imax;
2269 }
2270 }
2271 }
2272 }
2273 }
2274 }
2275
2276 Node* MemoryGraphFixer::collect_memory_for_infinite_loop(const Node* in) {
2277 Node* mem = nullptr;
2278 Node* head = in->in(0);
2279 assert(head->is_Region(), "unexpected infinite loop graph shape");
2280
2281 Node* phi_mem = nullptr;
2282 for (DUIterator_Fast jmax, j = head->fast_outs(jmax); j < jmax; j++) {
2283 Node* u = head->fast_out(j);
2284 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
2285 if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2286 assert(phi_mem == nullptr || phi_mem->adr_type() == TypePtr::BOTTOM, "");
2287 phi_mem = u;
2288 } else if (u->adr_type() == TypePtr::BOTTOM) {
2289 assert(phi_mem == nullptr || _phase->C->get_alias_index(phi_mem->adr_type()) == _alias, "");
2290 if (phi_mem == nullptr) {
2291 phi_mem = u;
2292 }
2293 }
2294 }
2295 }
2296 if (phi_mem == nullptr) {
2297 ResourceMark rm;
2298 Node_Stack stack(0);
2299 stack.push(head, 1);
2300 do {
2301 Node* n = stack.node();
2302 uint i = stack.index();
2303 if (i >= n->req()) {
2304 stack.pop();
2305 } else {
2306 stack.set_index(i + 1);
2307 Node* c = n->in(i);
2308 assert(c != head, "should have found a safepoint on the way");
2309 if (stack.size() != 1 || _phase->is_dominator(head, c)) {
2310 for (;;) {
2311 if (c->is_Region()) {
2312 stack.push(c, 1);
2313 break;
2314 } else if (c->is_SafePoint() && !c->is_CallLeaf()) {
2315 Node* m = c->in(TypeFunc::Memory);
2316 if (m->is_MergeMem()) {
2317 m = m->as_MergeMem()->memory_at(_alias);
2318 }
2319 assert(mem == nullptr || mem == m, "several memory states");
2320 mem = m;
2321 break;
2322 } else {
2323 assert(c != c->in(0), "");
2324 c = c->in(0);
2325 }
2326 }
2327 }
2328 }
2329 } while (stack.size() > 0);
2330 assert(mem != nullptr, "should have found safepoint");
2331 } else {
2332 mem = phi_mem;
2333 }
2334 return mem;
2335 }
2336
2337 Node* MemoryGraphFixer::get_ctrl(Node* n) const {
2338 Node* c = _phase->get_ctrl(n);
2339 if (n->is_Proj() && n->in(0) != nullptr && n->in(0)->is_Call()) {
2340 assert(c == n->in(0), "");
2341 CallNode* call = c->as_Call();
2342 CallProjections projs;
2343 call->extract_projections(&projs, true, false);
2344 if (projs.catchall_memproj != nullptr) {
2345 if (projs.fallthrough_memproj == n) {
2346 c = projs.fallthrough_catchproj;
2347 } else {
2348 assert(projs.catchall_memproj == n, "");
2349 c = projs.catchall_catchproj;
2350 }
2351 }
2352 }
2353 return c;
2354 }
2355
2356 Node* MemoryGraphFixer::ctrl_or_self(Node* n) const {
2357 if (_phase->has_ctrl(n))
2358 return get_ctrl(n);
2359 else {
2360 assert (n->is_CFG(), "must be a CFG node");
2361 return n;
2362 }
2363 }
2364
2365 bool MemoryGraphFixer::mem_is_valid(Node* m, Node* c) const {
2366 return m != nullptr && get_ctrl(m) == c;
2367 }
2368
2369 Node* MemoryGraphFixer::find_mem(Node* ctrl, Node* n) const {
2370 assert(n == nullptr || _phase->ctrl_or_self(n) == ctrl, "");
2371 assert(!ctrl->is_Call() || ctrl == n, "projection expected");
2372 #ifdef ASSERT
2373 if ((ctrl->is_Proj() && ctrl->in(0)->is_Call()) ||
2374 (ctrl->is_Catch() && ctrl->in(0)->in(0)->is_Call())) {
2375 CallNode* call = ctrl->is_Proj() ? ctrl->in(0)->as_Call() : ctrl->in(0)->in(0)->as_Call();
2376 int mems = 0;
2377 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) {
2378 Node* u = call->fast_out(i);
2379 if (u->bottom_type() == Type::MEMORY) {
2380 mems++;
2381 }
2382 }
2383 assert(mems <= 1, "No node right after call if multiple mem projections");
2384 }
2385 #endif
2386 Node* mem = _memory_nodes[ctrl->_idx];
2387 Node* c = ctrl;
2388 while (!mem_is_valid(mem, c) &&
2389 (!c->is_CatchProj() || mem == nullptr || c->in(0)->in(0)->in(0) != get_ctrl(mem))) {
2390 c = _phase->idom(c);
2391 mem = _memory_nodes[c->_idx];
2392 }
2393 if (n != nullptr && mem_is_valid(mem, c)) {
2394 while (!ShenandoahBarrierC2Support::is_dominator_same_ctrl(c, mem, n, _phase) && _phase->ctrl_or_self(mem) == ctrl) {
2395 mem = next_mem(mem, _alias);
2396 }
2397 if (mem->is_MergeMem()) {
2398 mem = mem->as_MergeMem()->memory_at(_alias);
2399 }
2400 if (!mem_is_valid(mem, c)) {
2401 do {
2402 c = _phase->idom(c);
2403 mem = _memory_nodes[c->_idx];
2404 } while (!mem_is_valid(mem, c) &&
2405 (!c->is_CatchProj() || mem == nullptr || c->in(0)->in(0)->in(0) != get_ctrl(mem)));
2406 }
2407 }
2408 assert(mem->bottom_type() == Type::MEMORY, "");
2409 return mem;
2410 }
2411
2412 bool MemoryGraphFixer::has_mem_phi(Node* region) const {
2413 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
2414 Node* use = region->fast_out(i);
2415 if (use->is_Phi() && use->bottom_type() == Type::MEMORY &&
2416 (_phase->C->get_alias_index(use->adr_type()) == _alias)) {
2417 return true;
2418 }
2419 }
2420 return false;
2421 }
2422
2423 void MemoryGraphFixer::fix_mem(Node* ctrl, Node* new_ctrl, Node* mem, Node* mem_for_ctrl, Node* new_mem, Unique_Node_List& uses) {
2424 assert(_phase->ctrl_or_self(new_mem) == new_ctrl, "");
2425 const bool trace = false;
2426 DEBUG_ONLY(if (trace) { tty->print("ZZZ control is"); ctrl->dump(); });
2427 DEBUG_ONLY(if (trace) { tty->print("ZZZ mem is"); mem->dump(); });
2428 GrowableArray<Node*> phis;
2429 if (mem_for_ctrl != mem) {
2430 Node* old = mem_for_ctrl;
2431 Node* prev = nullptr;
2432 while (old != mem) {
2433 prev = old;
2434 if (old->is_Store() || old->is_ClearArray() || old->is_LoadStore()) {
2435 assert(_alias == Compile::AliasIdxRaw, "");
2436 old = old->in(MemNode::Memory);
2437 } else if (old->Opcode() == Op_SCMemProj) {
2438 assert(_alias == Compile::AliasIdxRaw, "");
2439 old = old->in(0);
2440 } else {
2441 ShouldNotReachHere();
2442 }
2443 }
2444 assert(prev != nullptr, "");
2445 if (new_ctrl != ctrl) {
2446 _memory_nodes.map(ctrl->_idx, mem);
2447 _memory_nodes.map(new_ctrl->_idx, mem_for_ctrl);
2448 }
2449 uint input = (uint)MemNode::Memory;
2450 _phase->igvn().replace_input_of(prev, input, new_mem);
2451 } else {
2452 uses.clear();
2453 _memory_nodes.map(new_ctrl->_idx, new_mem);
2454 uses.push(new_ctrl);
2455 for(uint next = 0; next < uses.size(); next++ ) {
2456 Node *n = uses.at(next);
2457 assert(n->is_CFG(), "");
2458 DEBUG_ONLY(if (trace) { tty->print("ZZZ ctrl"); n->dump(); });
2459 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2460 Node* u = n->fast_out(i);
2461 if (!u->is_Root() && u->is_CFG() && u != n) {
2462 Node* m = _memory_nodes[u->_idx];
2463 if (u->is_Region() && (!u->is_OuterStripMinedLoop() || _include_lsm) &&
2464 !has_mem_phi(u) &&
2465 u->unique_ctrl_out()->Opcode() != Op_Halt) {
2466 DEBUG_ONLY(if (trace) { tty->print("ZZZ region"); u->dump(); });
2467 DEBUG_ONLY(if (trace && m != nullptr) { tty->print("ZZZ mem"); m->dump(); });
2468
2469 if (!mem_is_valid(m, u) || !m->is_Phi()) {
2470 bool push = true;
2471 bool create_phi = true;
2472 if (_phase->is_dominator(new_ctrl, u)) {
2473 create_phi = false;
2474 }
2475 if (create_phi) {
2476 Node* phi = new PhiNode(u, Type::MEMORY, _phase->C->get_adr_type(_alias));
2477 _phase->register_new_node(phi, u);
2478 phis.push(phi);
2479 DEBUG_ONLY(if (trace) { tty->print("ZZZ new phi"); phi->dump(); });
2480 if (!mem_is_valid(m, u)) {
2481 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting mem"); phi->dump(); });
2482 _memory_nodes.map(u->_idx, phi);
2483 } else {
2484 DEBUG_ONLY(if (trace) { tty->print("ZZZ NOT setting mem"); m->dump(); });
2485 for (;;) {
2486 assert(m->is_Mem() || m->is_LoadStore() || m->is_Proj(), "");
2487 Node* next = nullptr;
2488 if (m->is_Proj()) {
2489 next = m->in(0);
2490 } else {
2491 assert(m->is_Mem() || m->is_LoadStore(), "");
2492 assert(_alias == Compile::AliasIdxRaw, "");
2493 next = m->in(MemNode::Memory);
2494 }
2495 if (_phase->get_ctrl(next) != u) {
2496 break;
2497 }
2498 if (next->is_MergeMem()) {
2499 assert(_phase->get_ctrl(next->as_MergeMem()->memory_at(_alias)) != u, "");
2500 break;
2501 }
2502 if (next->is_Phi()) {
2503 assert(next->adr_type() == TypePtr::BOTTOM && next->in(0) == u, "");
2504 break;
2505 }
2506 m = next;
2507 }
2508
2509 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting to phi"); m->dump(); });
2510 assert(m->is_Mem() || m->is_LoadStore(), "");
2511 uint input = (uint)MemNode::Memory;
2512 _phase->igvn().replace_input_of(m, input, phi);
2513 push = false;
2514 }
2515 } else {
2516 DEBUG_ONLY(if (trace) { tty->print("ZZZ skipping region"); u->dump(); });
2517 }
2518 if (push) {
2519 uses.push(u);
2520 }
2521 }
2522 } else if (!mem_is_valid(m, u) &&
2523 !(u->Opcode() == Op_CProj && u->in(0)->is_NeverBranch() && u->as_Proj()->_con == 1)) {
2524 uses.push(u);
2525 }
2526 }
2527 }
2528 }
2529 for (int i = 0; i < phis.length(); i++) {
2530 Node* n = phis.at(i);
2531 Node* r = n->in(0);
2532 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi"); n->dump(); });
2533 for (uint j = 1; j < n->req(); j++) {
2534 Node* m = find_mem(r->in(j), nullptr);
2535 _phase->igvn().replace_input_of(n, j, m);
2536 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi: %d", j); m->dump(); });
2537 }
2538 }
2539 }
2540 uint last = _phase->C->unique();
2541 MergeMemNode* mm = nullptr;
2542 int alias = _alias;
2543 DEBUG_ONLY(if (trace) { tty->print("ZZZ raw mem is"); mem->dump(); });
2544 // Process loads first to not miss an anti-dependency: if the memory
2545 // edge of a store is updated before a load is processed then an
2546 // anti-dependency may be missed.
2547 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2548 Node* u = mem->out(i);
2549 if (u->_idx < last && u->is_Load() && _phase->C->get_alias_index(u->adr_type()) == alias) {
2550 Node* m = find_mem(_phase->get_ctrl(u), u);
2551 if (m != mem) {
2552 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2553 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2554 --i;
2555 }
2556 }
2557 }
2558 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2559 Node* u = mem->out(i);
2560 if (u->_idx < last) {
2561 if (u->is_Mem()) {
2562 if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2563 Node* m = find_mem(_phase->get_ctrl(u), u);
2564 if (m != mem) {
2565 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2566 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2567 --i;
2568 }
2569 }
2570 } else if (u->is_MergeMem()) {
2571 MergeMemNode* u_mm = u->as_MergeMem();
2572 if (u_mm->memory_at(alias) == mem) {
2573 MergeMemNode* newmm = nullptr;
2574 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2575 Node* uu = u->fast_out(j);
2576 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2577 if (uu->is_Phi()) {
2578 assert(uu->adr_type() == TypePtr::BOTTOM, "");
2579 Node* region = uu->in(0);
2580 int nb = 0;
2581 for (uint k = 1; k < uu->req(); k++) {
2582 if (uu->in(k) == u) {
2583 Node* m = find_mem(region->in(k), nullptr);
2584 if (m != mem) {
2585 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", k); uu->dump(); });
2586 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2587 if (newmm != u) {
2588 _phase->igvn().replace_input_of(uu, k, newmm);
2589 nb++;
2590 --jmax;
2591 }
2592 }
2593 }
2594 }
2595 if (nb > 0) {
2596 --j;
2597 }
2598 } else {
2599 Node* m = find_mem(_phase->ctrl_or_self(uu), uu);
2600 if (m != mem) {
2601 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); uu->dump(); });
2602 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2603 if (newmm != u) {
2604 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2605 --j, --jmax;
2606 }
2607 }
2608 }
2609 }
2610 }
2611 } else if (u->is_Phi()) {
2612 assert(u->bottom_type() == Type::MEMORY, "what else?");
2613 if (_phase->C->get_alias_index(u->adr_type()) == alias || u->adr_type() == TypePtr::BOTTOM) {
2614 Node* region = u->in(0);
2615 bool replaced = false;
2616 for (uint j = 1; j < u->req(); j++) {
2617 if (u->in(j) == mem) {
2618 Node* m = find_mem(region->in(j), nullptr);
2619 Node* nnew = m;
2620 if (m != mem) {
2621 if (u->adr_type() == TypePtr::BOTTOM) {
2622 mm = allocate_merge_mem(mem, m, _phase->ctrl_or_self(m));
2623 nnew = mm;
2624 }
2625 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", j); u->dump(); });
2626 _phase->igvn().replace_input_of(u, j, nnew);
2627 replaced = true;
2628 }
2629 }
2630 }
2631 if (replaced) {
2632 --i;
2633 }
2634 }
2635 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2636 u->adr_type() == nullptr) {
2637 assert(u->adr_type() != nullptr ||
2638 u->Opcode() == Op_Rethrow ||
2639 u->Opcode() == Op_Return ||
2640 u->Opcode() == Op_SafePoint ||
2641 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2642 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2643 u->Opcode() == Op_CallLeaf, "");
2644 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2645 if (m != mem) {
2646 mm = allocate_merge_mem(mem, m, _phase->get_ctrl(m));
2647 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2648 --i;
2649 }
2650 } else if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2651 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2652 if (m != mem) {
2653 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2654 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2655 --i;
2656 }
2657 } else if (u->adr_type() != TypePtr::BOTTOM &&
2658 _memory_nodes[_phase->ctrl_or_self(u)->_idx] == u) {
2659 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2660 assert(m != mem, "");
2661 // u is on the wrong slice...
2662 assert(u->is_ClearArray(), "");
2663 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2664 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2665 --i;
2666 }
2667 }
2668 }
2669 #ifdef ASSERT
2670 assert(new_mem->outcnt() > 0, "");
2671 for (int i = 0; i < phis.length(); i++) {
2672 Node* n = phis.at(i);
2673 assert(n->outcnt() > 0, "new phi must have uses now");
2674 }
2675 #endif
2676 }
2677
2678 void MemoryGraphFixer::record_new_ctrl(Node* ctrl, Node* new_ctrl, Node* mem, Node* mem_for_ctrl) {
2679 if (mem_for_ctrl != mem && new_ctrl != ctrl) {
2680 _memory_nodes.map(ctrl->_idx, mem);
2681 _memory_nodes.map(new_ctrl->_idx, mem_for_ctrl);
2682 }
2683 }
2684
2685 MergeMemNode* MemoryGraphFixer::allocate_merge_mem(Node* mem, Node* rep_proj, Node* rep_ctrl) const {
2686 MergeMemNode* mm = MergeMemNode::make(mem);
2687 mm->set_memory_at(_alias, rep_proj);
2688 _phase->register_new_node(mm, rep_ctrl);
2689 return mm;
2690 }
2691
2692 MergeMemNode* MemoryGraphFixer::clone_merge_mem(Node* u, Node* mem, Node* rep_proj, Node* rep_ctrl, DUIterator& i) const {
2693 MergeMemNode* newmm = nullptr;
2694 MergeMemNode* u_mm = u->as_MergeMem();
2695 Node* c = _phase->get_ctrl(u);
2696 if (_phase->is_dominator(c, rep_ctrl)) {
2697 c = rep_ctrl;
2698 } else {
2699 assert(_phase->is_dominator(rep_ctrl, c), "one must dominate the other");
2700 }
2701 if (u->outcnt() == 1) {
2702 if (u->req() > (uint)_alias && u->in(_alias) == mem) {
2703 _phase->igvn().replace_input_of(u, _alias, rep_proj);
2704 --i;
2705 } else {
2706 _phase->igvn().rehash_node_delayed(u);
2707 u_mm->set_memory_at(_alias, rep_proj);
2708 }
2709 newmm = u_mm;
2710 _phase->set_ctrl_and_loop(u, c);
2711 } else {
2712 // can't simply clone u and then change one of its input because
2713 // it adds and then removes an edge which messes with the
2714 // DUIterator
2715 newmm = MergeMemNode::make(u_mm->base_memory());
2716 for (uint j = 0; j < u->req(); j++) {
2717 if (j < newmm->req()) {
2718 if (j == (uint)_alias) {
2719 newmm->set_req(j, rep_proj);
2720 } else if (newmm->in(j) != u->in(j)) {
2721 newmm->set_req(j, u->in(j));
2722 }
2723 } else if (j == (uint)_alias) {
2724 newmm->add_req(rep_proj);
2725 } else {
2726 newmm->add_req(u->in(j));
2727 }
2728 }
2729 if ((uint)_alias >= u->req()) {
2730 newmm->set_memory_at(_alias, rep_proj);
2731 }
2732 _phase->register_new_node(newmm, c);
2733 }
2734 return newmm;
2735 }
2736
2737 bool MemoryGraphFixer::should_process_phi(Node* phi) const {
2738 if (phi->adr_type() == TypePtr::BOTTOM) {
2739 Node* region = phi->in(0);
2740 for (DUIterator_Fast jmax, j = region->fast_outs(jmax); j < jmax; j++) {
2741 Node* uu = region->fast_out(j);
2742 if (uu->is_Phi() && uu != phi && uu->bottom_type() == Type::MEMORY && _phase->C->get_alias_index(uu->adr_type()) == _alias) {
2743 return false;
2744 }
2745 }
2746 return true;
2747 }
2748 return _phase->C->get_alias_index(phi->adr_type()) == _alias;
2749 }
2750
2751 void MemoryGraphFixer::fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl) const {
2752 uint last = _phase-> C->unique();
2753 MergeMemNode* mm = nullptr;
2754 assert(mem->bottom_type() == Type::MEMORY, "");
2755 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2756 Node* u = mem->out(i);
2757 if (u != replacement && u->_idx < last) {
2758 if (u->is_MergeMem()) {
2759 MergeMemNode* u_mm = u->as_MergeMem();
2760 if (u_mm->memory_at(_alias) == mem) {
2761 MergeMemNode* newmm = nullptr;
2762 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2763 Node* uu = u->fast_out(j);
2764 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2765 if (uu->is_Phi()) {
2766 if (should_process_phi(uu)) {
2767 Node* region = uu->in(0);
2768 int nb = 0;
2769 for (uint k = 1; k < uu->req(); k++) {
2770 if (uu->in(k) == u && _phase->is_dominator(rep_ctrl, region->in(k))) {
2771 if (newmm == nullptr) {
2772 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2773 }
2774 if (newmm != u) {
2775 _phase->igvn().replace_input_of(uu, k, newmm);
2776 nb++;
2777 --jmax;
2778 }
2779 }
2780 }
2781 if (nb > 0) {
2782 --j;
2783 }
2784 }
2785 } else {
2786 if (rep_ctrl != uu && ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(uu), replacement, uu, _phase)) {
2787 if (newmm == nullptr) {
2788 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2789 }
2790 if (newmm != u) {
2791 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2792 --j, --jmax;
2793 }
2794 }
2795 }
2796 }
2797 }
2798 } else if (u->is_Phi()) {
2799 assert(u->bottom_type() == Type::MEMORY, "what else?");
2800 Node* region = u->in(0);
2801 if (should_process_phi(u)) {
2802 bool replaced = false;
2803 for (uint j = 1; j < u->req(); j++) {
2804 if (u->in(j) == mem && _phase->is_dominator(rep_ctrl, region->in(j))) {
2805 Node* nnew = rep_proj;
2806 if (u->adr_type() == TypePtr::BOTTOM) {
2807 if (mm == nullptr) {
2808 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2809 }
2810 nnew = mm;
2811 }
2812 _phase->igvn().replace_input_of(u, j, nnew);
2813 replaced = true;
2814 }
2815 }
2816 if (replaced) {
2817 --i;
2818 }
2819
2820 }
2821 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2822 u->adr_type() == nullptr) {
2823 assert(u->adr_type() != nullptr ||
2824 u->Opcode() == Op_Rethrow ||
2825 u->Opcode() == Op_Return ||
2826 u->Opcode() == Op_SafePoint ||
2827 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2828 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2829 u->Opcode() == Op_CallLeaf, "%s", u->Name());
2830 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2831 if (mm == nullptr) {
2832 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2833 }
2834 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2835 --i;
2836 }
2837 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2838 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2839 _phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
2840 --i;
2841 }
2842 }
2843 }
2844 }
2845 }
2846
2847 ShenandoahLoadReferenceBarrierNode::ShenandoahLoadReferenceBarrierNode(Node* ctrl, Node* obj, DecoratorSet decorators)
2848 : Node(ctrl, obj), _decorators(decorators) {
2849 ShenandoahBarrierSetC2::bsc2()->state()->add_load_reference_barrier(this);
2850 }
2851
2852 DecoratorSet ShenandoahLoadReferenceBarrierNode::decorators() const {
2853 return _decorators;
2854 }
2855
2856 uint ShenandoahLoadReferenceBarrierNode::size_of() const {
2857 return sizeof(*this);
2858 }
2859
2860 static DecoratorSet mask_decorators(DecoratorSet decorators) {
2861 return decorators & (ON_STRONG_OOP_REF | ON_WEAK_OOP_REF | ON_PHANTOM_OOP_REF | ON_UNKNOWN_OOP_REF | IN_NATIVE);
2862 }
2863
2864 uint ShenandoahLoadReferenceBarrierNode::hash() const {
2865 uint hash = Node::hash();
2866 hash += mask_decorators(_decorators);
2867 return hash;
2868 }
2869
2870 bool ShenandoahLoadReferenceBarrierNode::cmp( const Node &n ) const {
2871 return Node::cmp(n) && n.Opcode() == Op_ShenandoahLoadReferenceBarrier &&
2872 mask_decorators(_decorators) == mask_decorators(((const ShenandoahLoadReferenceBarrierNode&)n)._decorators);
2873 }
2874
2875 const Type* ShenandoahLoadReferenceBarrierNode::bottom_type() const {
2876 if (in(ValueIn) == nullptr || in(ValueIn)->is_top()) {
2877 return Type::TOP;
2878 }
2879 const Type* t = in(ValueIn)->bottom_type();
2880 if (t == TypePtr::NULL_PTR) {
2881 return t;
2882 }
2883
2884 if (ShenandoahBarrierSet::is_strong_access(decorators())) {
2885 return t;
2886 }
2887
2888 return t->meet(TypePtr::NULL_PTR);
2889 }
2890
2891 const Type* ShenandoahLoadReferenceBarrierNode::Value(PhaseGVN* phase) const {
2892 // Either input is TOP ==> the result is TOP
2893 const Type *t2 = phase->type(in(ValueIn));
2894 if( t2 == Type::TOP ) return Type::TOP;
2895
2896 if (t2 == TypePtr::NULL_PTR) {
2897 return t2;
2898 }
2899
2900 if (ShenandoahBarrierSet::is_strong_access(decorators())) {
2901 return t2;
2902 }
2903
2904 return t2->meet(TypePtr::NULL_PTR);
2905 }
2906
2907 Node* ShenandoahLoadReferenceBarrierNode::Identity(PhaseGVN* phase) {
2908 Node* value = in(ValueIn);
2909 if (!needs_barrier(phase, value)) {
2910 return value;
2911 }
2912 return this;
2913 }
2914
2915 bool ShenandoahLoadReferenceBarrierNode::needs_barrier(PhaseGVN* phase, Node* n) {
2916 Unique_Node_List visited;
2917 return needs_barrier_impl(phase, n, visited);
2918 }
2919
2920 bool ShenandoahLoadReferenceBarrierNode::needs_barrier_impl(PhaseGVN* phase, Node* n, Unique_Node_List &visited) {
2921 if (n == nullptr) return false;
2922 if (visited.member(n)) {
2923 return false; // Been there.
2924 }
2925 visited.push(n);
2926
2927 if (n->is_Allocate()) {
2928 // tty->print_cr("optimize barrier on alloc");
2929 return false;
2930 }
2931 if (n->is_Call()) {
2932 // tty->print_cr("optimize barrier on call");
2933 return false;
2934 }
2935
2936 const Type* type = phase->type(n);
2937 if (type == Type::TOP) {
2938 return false;
2939 }
2940 if (type->make_ptr()->higher_equal(TypePtr::NULL_PTR)) {
2941 // tty->print_cr("optimize barrier on null");
2942 return false;
2943 }
2944 if (type->make_oopptr() && type->make_oopptr()->const_oop() != nullptr) {
2945 // tty->print_cr("optimize barrier on constant");
2946 return false;
2947 }
2948
2949 switch (n->Opcode()) {
2950 case Op_AddP:
2951 return true; // TODO: Can refine?
2952 case Op_LoadP:
2953 case Op_ShenandoahCompareAndExchangeN:
2954 case Op_ShenandoahCompareAndExchangeP:
2955 case Op_CompareAndExchangeN:
2956 case Op_CompareAndExchangeP:
2957 case Op_GetAndSetN:
2958 case Op_GetAndSetP:
2959 return true;
2960 case Op_Phi: {
2961 for (uint i = 1; i < n->req(); i++) {
2962 if (needs_barrier_impl(phase, n->in(i), visited)) return true;
2963 }
2964 return false;
2965 }
2966 case Op_CheckCastPP:
2967 case Op_CastPP:
2968 return needs_barrier_impl(phase, n->in(1), visited);
2969 case Op_Proj:
2970 return needs_barrier_impl(phase, n->in(0), visited);
2971 case Op_ShenandoahLoadReferenceBarrier:
2972 // tty->print_cr("optimize barrier on barrier");
2973 return false;
2974 case Op_Parm:
2975 // tty->print_cr("optimize barrier on input arg");
2976 return false;
2977 case Op_DecodeN:
2978 case Op_EncodeP:
2979 return needs_barrier_impl(phase, n->in(1), visited);
2980 case Op_LoadN:
2981 return true;
2982 case Op_CMoveN:
2983 case Op_CMoveP:
2984 return needs_barrier_impl(phase, n->in(2), visited) ||
2985 needs_barrier_impl(phase, n->in(3), visited);
2986 case Op_ShenandoahIUBarrier:
2987 return needs_barrier_impl(phase, n->in(1), visited);
2988 case Op_CreateEx:
2989 return false;
2990 default:
2991 break;
2992 }
2993 #ifdef ASSERT
2994 tty->print("need barrier on?: ");
2995 tty->print_cr("ins:");
2996 n->dump(2);
2997 tty->print_cr("outs:");
2998 n->dump(-2);
2999 ShouldNotReachHere();
3000 #endif
3001 return true;
3002 }