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
27 #include "classfile/javaClasses.hpp"
28 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
29 #include "gc/shenandoah/c2/shenandoahSupport.hpp"
30 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp"
31 #include "gc/shenandoah/shenandoahForwarding.hpp"
32 #include "gc/shenandoah/shenandoahHeap.hpp"
33 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
34 #include "gc/shenandoah/shenandoahRuntime.hpp"
35 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
36 #include "opto/arraycopynode.hpp"
37 #include "opto/block.hpp"
38 #include "opto/callnode.hpp"
39 #include "opto/castnode.hpp"
40 #include "opto/movenode.hpp"
41 #include "opto/phaseX.hpp"
42 #include "opto/rootnode.hpp"
43 #include "opto/runtime.hpp"
44 #include "opto/subnode.hpp"
45
46 bool ShenandoahBarrierC2Support::expand(Compile* C, PhaseIterGVN& igvn) {
47 ShenandoahBarrierSetC2State* state = ShenandoahBarrierSetC2::bsc2()->state();
48 if (state->load_reference_barriers_count() > 0) {
49 assert(C->post_loop_opts_phase(), "no loop opts allowed");
50 C->reset_post_loop_opts_phase(); // ... but we know what we are doing
51 C->clear_major_progress();
52 PhaseIdealLoop::optimize(igvn, LoopOptsShenandoahExpand);
53 if (C->failing()) return false;
54 C->process_for_post_loop_opts_igvn(igvn);
55 if (C->failing()) return false;
56
57 C->set_post_loop_opts_phase(); // now for real!
58 }
59 return true;
60 }
61
62 bool ShenandoahBarrierC2Support::is_gc_state_test(Node* iff, int mask) {
63 if (!UseShenandoahGC) {
64 return false;
65 }
66 assert(iff->is_If(), "bad input");
67 if (iff->Opcode() != Op_If) {
68 return false;
69 }
70 Node* bol = iff->in(1);
71 if (!bol->is_Bool() || bol->as_Bool()->_test._test != BoolTest::ne) {
72 return false;
73 }
74 Node* cmp = bol->in(1);
75 if (cmp->Opcode() != Op_CmpI) {
76 return false;
77 }
78 Node* in1 = cmp->in(1);
79 Node* in2 = cmp->in(2);
80 if (in2->find_int_con(-1) != 0) {
81 return false;
82 }
83 if (in1->Opcode() != Op_AndI) {
84 return false;
85 }
86 in2 = in1->in(2);
87 if (in2->find_int_con(-1) != mask) {
88 return false;
89 }
90 in1 = in1->in(1);
91
92 return is_gc_state_load(in1);
93 }
94
95 bool ShenandoahBarrierC2Support::is_heap_stable_test(Node* iff) {
96 return is_gc_state_test(iff, ShenandoahHeap::HAS_FORWARDED);
97 }
98
99 bool ShenandoahBarrierC2Support::is_gc_state_load(Node *n) {
100 if (!UseShenandoahGC) {
101 return false;
102 }
103 if (n->Opcode() != Op_LoadB && n->Opcode() != Op_LoadUB) {
104 return false;
105 }
106 Node* addp = n->in(MemNode::Address);
107 if (!addp->is_AddP()) {
108 return false;
109 }
110 Node* base = addp->in(AddPNode::Address);
111 Node* off = addp->in(AddPNode::Offset);
112 if (base->Opcode() != Op_ThreadLocal) {
113 return false;
114 }
115 if (off->find_intptr_t_con(-1) != in_bytes(ShenandoahThreadLocalData::gc_state_offset())) {
116 return false;
117 }
118 return true;
119 }
120
121 bool ShenandoahBarrierC2Support::has_safepoint_between(Node* start, Node* stop, PhaseIdealLoop *phase) {
122 assert(phase->is_dominator(stop, start), "bad inputs");
123 ResourceMark rm;
124 Unique_Node_List wq;
125 wq.push(start);
126 for (uint next = 0; next < wq.size(); next++) {
127 Node *m = wq.at(next);
128 if (m == stop) {
129 continue;
130 }
131 if (m->is_SafePoint() && !m->is_CallLeaf()) {
132 return true;
133 }
134 if (m->is_Region()) {
135 for (uint i = 1; i < m->req(); i++) {
136 wq.push(m->in(i));
137 }
138 } else {
139 wq.push(m->in(0));
140 }
141 }
142 return false;
143 }
144
145 #ifdef ASSERT
146 bool ShenandoahBarrierC2Support::verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used) {
147 assert(phis.size() == 0, "");
148
149 while (true) {
150 if (in->bottom_type() == TypePtr::NULL_PTR) {
151 if (trace) {tty->print_cr("null");}
152 } else if (!in->bottom_type()->make_ptr()->make_oopptr()) {
153 if (trace) {tty->print_cr("Non oop");}
154 } else {
155 if (in->is_ConstraintCast()) {
156 in = in->in(1);
157 continue;
158 } else if (in->is_AddP()) {
159 assert(!in->in(AddPNode::Address)->is_top(), "no raw memory access");
160 in = in->in(AddPNode::Address);
161 continue;
162 } else if (in->is_Con()) {
163 if (trace) {
164 tty->print("Found constant");
165 in->dump();
166 }
167 } else if (in->Opcode() == Op_Parm) {
168 if (trace) {
169 tty->print("Found argument");
170 }
171 } else if (in->Opcode() == Op_CreateEx) {
172 if (trace) {
173 tty->print("Found create-exception");
174 }
175 } else if (in->Opcode() == Op_LoadP && in->adr_type() == TypeRawPtr::BOTTOM) {
176 if (trace) {
177 tty->print("Found raw LoadP (OSR argument?)");
178 }
179 } else if (in->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
180 if (t == ShenandoahOopStore) {
181 return false;
182 }
183 barriers_used.push(in);
184 if (trace) {tty->print("Found barrier"); in->dump();}
185 } else if (in->is_Proj() && in->in(0)->is_Allocate()) {
186 if (trace) {
187 tty->print("Found alloc");
188 in->in(0)->dump();
189 }
190 } else if (in->is_Proj() && (in->in(0)->Opcode() == Op_CallStaticJava || in->in(0)->Opcode() == Op_CallDynamicJava)) {
191 if (trace) {
192 tty->print("Found Java call");
193 }
194 } else if (in->is_Phi()) {
195 if (!visited.test_set(in->_idx)) {
196 if (trace) {tty->print("Pushed phi:"); in->dump();}
197 phis.push(in, 2);
198 in = in->in(1);
199 continue;
200 }
201 if (trace) {tty->print("Already seen phi:"); in->dump();}
202 } else if (in->Opcode() == Op_CMoveP || in->Opcode() == Op_CMoveN) {
203 if (!visited.test_set(in->_idx)) {
204 if (trace) {tty->print("Pushed cmovep:"); in->dump();}
205 phis.push(in, CMoveNode::IfTrue);
206 in = in->in(CMoveNode::IfFalse);
207 continue;
208 }
209 if (trace) {tty->print("Already seen cmovep:"); in->dump();}
210 } else if (in->Opcode() == Op_EncodeP || in->Opcode() == Op_DecodeN) {
211 in = in->in(1);
212 continue;
213 } else {
214 return false;
215 }
216 }
217 bool cont = false;
218 while (phis.is_nonempty()) {
219 uint idx = phis.index();
220 Node* phi = phis.node();
221 if (idx >= phi->req()) {
222 if (trace) {tty->print("Popped phi:"); phi->dump();}
223 phis.pop();
224 continue;
225 }
226 if (trace) {tty->print("Next entry(%d) for phi:", idx); phi->dump();}
227 in = phi->in(idx);
228 phis.set_index(idx+1);
229 cont = true;
230 break;
231 }
232 if (!cont) {
233 break;
234 }
235 }
236 return true;
237 }
238
239 void ShenandoahBarrierC2Support::report_verify_failure(const char* msg, Node* n1, Node* n2) {
240 if (n1 != nullptr) {
241 n1->dump(+10);
242 }
243 if (n2 != nullptr) {
244 n2->dump(+10);
245 }
246 fatal("%s", msg);
247 }
248
249 void ShenandoahBarrierC2Support::verify(RootNode* root) {
250 ResourceMark rm;
251 Unique_Node_List wq;
252 GrowableArray<Node*> barriers;
253 Unique_Node_List barriers_used;
254 Node_Stack phis(0);
255 VectorSet visited;
256 const bool trace = false;
257 const bool verify_no_useless_barrier = false;
258
259 wq.push(root);
260 for (uint next = 0; next < wq.size(); next++) {
261 Node *n = wq.at(next);
262 if (n->is_Load()) {
263 const bool trace = false;
264 if (trace) {tty->print("Verifying"); n->dump();}
265 if (n->Opcode() == Op_LoadRange || n->Opcode() == Op_LoadKlass || n->Opcode() == Op_LoadNKlass) {
266 if (trace) {tty->print_cr("Load range/klass");}
267 } else {
268 const TypePtr* adr_type = n->as_Load()->adr_type();
269
270 if (adr_type->isa_oopptr() && adr_type->is_oopptr()->offset() == oopDesc::mark_offset_in_bytes()) {
271 if (trace) {tty->print_cr("Mark load");}
272 } else if (adr_type->isa_instptr() &&
273 adr_type->is_instptr()->instance_klass()->is_subtype_of(Compile::current()->env()->Reference_klass()) &&
274 adr_type->is_instptr()->offset() == java_lang_ref_Reference::referent_offset()) {
275 if (trace) {tty->print_cr("Reference.get()");}
276 } else if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahLoad, trace, barriers_used)) {
277 report_verify_failure("Shenandoah verification: Load should have barriers", n);
278 }
279 }
280 } else if (n->is_Store()) {
281 const bool trace = false;
282
283 if (trace) {tty->print("Verifying"); n->dump();}
284 if (n->in(MemNode::ValueIn)->bottom_type()->make_oopptr()) {
285 Node* adr = n->in(MemNode::Address);
286 bool verify = true;
287
288 if (adr->is_AddP() && adr->in(AddPNode::Base)->is_top()) {
289 adr = adr->in(AddPNode::Address);
290 if (adr->is_AddP()) {
291 assert(adr->in(AddPNode::Base)->is_top(), "");
292 adr = adr->in(AddPNode::Address);
293 if (adr->Opcode() == Op_LoadP &&
294 adr->in(MemNode::Address)->in(AddPNode::Base)->is_top() &&
295 adr->in(MemNode::Address)->in(AddPNode::Address)->Opcode() == Op_ThreadLocal &&
296 adr->in(MemNode::Address)->in(AddPNode::Offset)->find_intptr_t_con(-1) == in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset())) {
297 if (trace) {tty->print_cr("SATB prebarrier");}
298 verify = false;
299 }
300 }
301 }
302
303 if (verify && !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahValue, trace, barriers_used)) {
304 report_verify_failure("Shenandoah verification: Store should have barriers", n);
305 }
306 }
307 if (!verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
308 report_verify_failure("Shenandoah verification: Store (address) should have barriers", n);
309 }
310 } else if (n->Opcode() == Op_CmpP) {
311 const bool trace = false;
312
313 Node* in1 = n->in(1);
314 Node* in2 = n->in(2);
315 if (in1->bottom_type()->isa_oopptr()) {
316 if (trace) {tty->print("Verifying"); n->dump();}
317
318 bool mark_inputs = false;
319 if (in1->bottom_type() == TypePtr::NULL_PTR || in2->bottom_type() == TypePtr::NULL_PTR ||
320 (in1->is_Con() || in2->is_Con())) {
321 if (trace) {tty->print_cr("Comparison against a constant");}
322 mark_inputs = true;
323 } else if ((in1->is_CheckCastPP() && in1->in(1)->is_Proj() && in1->in(1)->in(0)->is_Allocate()) ||
324 (in2->is_CheckCastPP() && in2->in(1)->is_Proj() && in2->in(1)->in(0)->is_Allocate())) {
325 if (trace) {tty->print_cr("Comparison with newly alloc'ed object");}
326 mark_inputs = true;
327 } else {
328 assert(in2->bottom_type()->isa_oopptr(), "");
329
330 if (!verify_helper(in1, phis, visited, ShenandoahStore, trace, barriers_used) ||
331 !verify_helper(in2, phis, visited, ShenandoahStore, trace, barriers_used)) {
332 report_verify_failure("Shenandoah verification: Cmp should have barriers", n);
333 }
334 }
335 if (verify_no_useless_barrier &&
336 mark_inputs &&
337 (!verify_helper(in1, phis, visited, ShenandoahValue, trace, barriers_used) ||
338 !verify_helper(in2, phis, visited, ShenandoahValue, trace, barriers_used))) {
339 phis.clear();
340 visited.reset();
341 }
342 }
343 } else if (n->is_LoadStore()) {
344 if (n->in(MemNode::ValueIn)->bottom_type()->make_ptr() &&
345 !verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahValue, trace, barriers_used)) {
346 report_verify_failure("Shenandoah verification: LoadStore (value) should have barriers", n);
347 }
348
349 if (n->in(MemNode::Address)->bottom_type()->make_oopptr() && !verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
350 report_verify_failure("Shenandoah verification: LoadStore (address) should have barriers", n);
351 }
352 } else if (n->Opcode() == Op_CallLeafNoFP || n->Opcode() == Op_CallLeaf) {
353 CallNode* call = n->as_Call();
354
355 static struct {
356 const char* name;
357 struct {
358 int pos;
359 verify_type t;
360 } args[6];
361 } calls[] = {
362 "array_partition_stub",
363 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+4, ShenandoahStore }, { -1, ShenandoahNone },
364 { -1, ShenandoahNone }, { -1, ShenandoahNone }, { -1, ShenandoahNone } },
365 "arraysort_stub",
366 { { TypeFunc::Parms, ShenandoahStore }, { -1, ShenandoahNone }, { -1, ShenandoahNone },
367 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
368 "aescrypt_encryptBlock",
369 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
370 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
371 "aescrypt_decryptBlock",
372 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
373 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
374 "multiplyToLen",
375 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { TypeFunc::Parms+4, ShenandoahStore },
376 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
377 "squareToLen",
378 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { -1, ShenandoahNone},
379 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
380 "montgomery_multiply",
381 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
382 { TypeFunc::Parms+6, ShenandoahStore }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
383 "montgomery_square",
384 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+5, ShenandoahStore },
385 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
386 "mulAdd",
387 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
388 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
389 "vectorizedMismatch",
390 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
391 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
392 "updateBytesCRC32",
393 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
394 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
395 "updateBytesAdler32",
396 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
397 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
398 "updateBytesCRC32C",
399 { { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahLoad}, { -1, ShenandoahNone},
400 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
401 "counterMode_AESCrypt",
402 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
403 { TypeFunc::Parms+3, ShenandoahStore }, { TypeFunc::Parms+5, ShenandoahStore }, { TypeFunc::Parms+6, ShenandoahStore } },
404 "cipherBlockChaining_encryptAESCrypt",
405 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
406 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
407 "cipherBlockChaining_decryptAESCrypt",
408 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
409 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
410 "shenandoah_clone",
411 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
412 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
413 "ghash_processBlocks",
414 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
415 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
416 "sha1_implCompress",
417 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
418 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
419 "sha256_implCompress",
420 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
421 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
422 "sha512_implCompress",
423 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
424 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
425 "sha1_implCompressMB",
426 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
427 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
428 "sha256_implCompressMB",
429 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
430 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
431 "sha512_implCompressMB",
432 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
433 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
434 "encodeBlock",
435 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
436 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
437 "decodeBlock",
438 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahStore }, { -1, ShenandoahNone },
439 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
440 "intpoly_montgomeryMult_P256",
441 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahStore },
442 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
443 "intpoly_assign",
444 { { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad }, { -1, ShenandoahNone },
445 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
446 };
447
448 if (call->is_call_to_arraycopystub()) {
449 Node* dest = nullptr;
450 const TypeTuple* args = n->as_Call()->_tf->domain_sig();
451 for (uint i = TypeFunc::Parms, j = 0; i < args->cnt(); i++) {
452 if (args->field_at(i)->isa_ptr()) {
453 j++;
454 if (j == 2) {
455 dest = n->in(i);
456 break;
457 }
458 }
459 }
460 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahLoad, trace, barriers_used) ||
461 !verify_helper(dest, phis, visited, ShenandoahStore, trace, barriers_used)) {
462 report_verify_failure("Shenandoah verification: ArrayCopy should have barriers", n);
463 }
464 } else if (strlen(call->_name) > 5 &&
465 !strcmp(call->_name + strlen(call->_name) - 5, "_fill")) {
466 if (!verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahStore, trace, barriers_used)) {
467 report_verify_failure("Shenandoah verification: _fill should have barriers", n);
468 }
469 } else if (!strcmp(call->_name, "shenandoah_wb_pre")) {
470 // skip
471 } else {
472 const int calls_len = sizeof(calls) / sizeof(calls[0]);
473 int i = 0;
474 for (; i < calls_len; i++) {
475 if (!strcmp(calls[i].name, call->_name)) {
476 break;
477 }
478 }
479 if (i != calls_len) {
480 const uint args_len = sizeof(calls[0].args) / sizeof(calls[0].args[0]);
481 for (uint j = 0; j < args_len; j++) {
482 int pos = calls[i].args[j].pos;
483 if (pos == -1) {
484 break;
485 }
486 if (!verify_helper(call->in(pos), phis, visited, calls[i].args[j].t, trace, barriers_used)) {
487 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
488 }
489 }
490 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
491 if (call->in(j)->bottom_type()->make_ptr() &&
492 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
493 uint k = 0;
494 for (; k < args_len && calls[i].args[k].pos != (int)j; k++);
495 if (k == args_len) {
496 fatal("arg %d for call %s not covered", j, call->_name);
497 }
498 }
499 }
500 } else {
501 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
502 if (call->in(j)->bottom_type()->make_ptr() &&
503 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
504 fatal("%s not covered", call->_name);
505 }
506 }
507 }
508 }
509 } else if (n->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
510 // skip
511 } else if (n->is_AddP()
512 || n->is_Phi()
513 || n->is_ConstraintCast()
514 || n->Opcode() == Op_Return
515 || n->Opcode() == Op_CMoveP
516 || n->Opcode() == Op_CMoveN
517 || n->Opcode() == Op_Rethrow
518 || n->is_MemBar()
519 || n->Opcode() == Op_Conv2B
520 || n->Opcode() == Op_SafePoint
521 || n->is_CallJava()
522 || n->Opcode() == Op_Unlock
523 || n->Opcode() == Op_EncodeP
524 || n->Opcode() == Op_DecodeN) {
525 // nothing to do
526 } else {
527 static struct {
528 int opcode;
529 struct {
530 int pos;
531 verify_type t;
532 } inputs[2];
533 } others[] = {
534 Op_FastLock,
535 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
536 Op_Lock,
537 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone} },
538 Op_ArrayCopy,
539 { { ArrayCopyNode::Src, ShenandoahLoad }, { ArrayCopyNode::Dest, ShenandoahStore } },
540 Op_StrCompressedCopy,
541 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
542 Op_StrInflatedCopy,
543 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
544 Op_AryEq,
545 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
546 Op_StrIndexOf,
547 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
548 Op_StrComp,
549 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
550 Op_StrEquals,
551 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
552 Op_VectorizedHashCode,
553 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
554 Op_EncodeISOArray,
555 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
556 Op_CountPositives,
557 { { 2, ShenandoahLoad }, { -1, ShenandoahNone} },
558 Op_CastP2X,
559 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
560 Op_StrIndexOfChar,
561 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
562 };
563
564 const int others_len = sizeof(others) / sizeof(others[0]);
565 int i = 0;
566 for (; i < others_len; i++) {
567 if (others[i].opcode == n->Opcode()) {
568 break;
569 }
570 }
571 uint stop = n->is_Call() ? n->as_Call()->tf()->domain_sig()->cnt() : n->req();
572 if (i != others_len) {
573 const uint inputs_len = sizeof(others[0].inputs) / sizeof(others[0].inputs[0]);
574 for (uint j = 0; j < inputs_len; j++) {
575 int pos = others[i].inputs[j].pos;
576 if (pos == -1) {
577 break;
578 }
579 if (!verify_helper(n->in(pos), phis, visited, others[i].inputs[j].t, trace, barriers_used)) {
580 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
581 }
582 }
583 for (uint j = 1; j < stop; j++) {
584 if (n->in(j) != nullptr && n->in(j)->bottom_type()->make_ptr() &&
585 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
586 uint k = 0;
587 for (; k < inputs_len && others[i].inputs[k].pos != (int)j; k++);
588 if (k == inputs_len) {
589 fatal("arg %d for node %s not covered", j, n->Name());
590 }
591 }
592 }
593 } else {
594 for (uint j = 1; j < stop; j++) {
595 if (n->in(j) != nullptr && n->in(j)->bottom_type()->make_ptr() &&
596 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
597 fatal("%s not covered", n->Name());
598 }
599 }
600 }
601 }
602
603 if (n->is_SafePoint()) {
604 SafePointNode* sfpt = n->as_SafePoint();
605 if (verify_no_useless_barrier && sfpt->jvms() != nullptr) {
606 for (uint i = sfpt->jvms()->scloff(); i < sfpt->jvms()->endoff(); i++) {
607 if (!verify_helper(sfpt->in(i), phis, visited, ShenandoahLoad, trace, barriers_used)) {
608 phis.clear();
609 visited.reset();
610 }
611 }
612 }
613 }
614 }
615
616 if (verify_no_useless_barrier) {
617 for (int i = 0; i < barriers.length(); i++) {
618 Node* n = barriers.at(i);
619 if (!barriers_used.member(n)) {
620 tty->print("XXX useless barrier"); n->dump(-2);
621 ShouldNotReachHere();
622 }
623 }
624 }
625 }
626 #endif
627
628 bool ShenandoahBarrierC2Support::is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase) {
629 // That both nodes have the same control is not sufficient to prove
630 // domination, verify that there's no path from d to n
631 ResourceMark rm;
632 Unique_Node_List wq;
633 wq.push(d);
634 for (uint next = 0; next < wq.size(); next++) {
635 Node *m = wq.at(next);
636 if (m == n) {
637 return false;
638 }
639 if (m->is_Phi() && m->in(0)->is_Loop()) {
640 assert(phase->ctrl_or_self(m->in(LoopNode::EntryControl)) != c, "following loop entry should lead to new control");
641 } else {
642 if (m->is_Store() || m->is_LoadStore()) {
643 // Take anti-dependencies into account
644 Node* mem = m->in(MemNode::Memory);
645 for (DUIterator_Fast imax, i = mem->fast_outs(imax); i < imax; i++) {
646 Node* u = mem->fast_out(i);
647 if (u->is_Load() && phase->C->can_alias(m->adr_type(), phase->C->get_alias_index(u->adr_type())) &&
648 phase->ctrl_or_self(u) == c) {
649 wq.push(u);
650 }
651 }
652 }
653 for (uint i = 0; i < m->req(); i++) {
654 if (m->in(i) != nullptr && phase->ctrl_or_self(m->in(i)) == c) {
655 wq.push(m->in(i));
656 }
657 }
658 }
659 }
660 return true;
661 }
662
663 bool ShenandoahBarrierC2Support::is_dominator(Node* d_c, Node* n_c, Node* d, Node* n, PhaseIdealLoop* phase) {
664 if (d_c != n_c) {
665 return phase->is_dominator(d_c, n_c);
666 }
667 return is_dominator_same_ctrl(d_c, d, n, phase);
668 }
669
670 Node* next_mem(Node* mem, int alias) {
671 Node* res = nullptr;
672 if (mem->is_Proj()) {
673 res = mem->in(0);
674 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
675 res = mem->in(TypeFunc::Memory);
676 } else if (mem->is_Phi()) {
677 res = mem->in(1);
678 } else if (mem->is_MergeMem()) {
679 res = mem->as_MergeMem()->memory_at(alias);
680 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
681 assert(alias == Compile::AliasIdxRaw, "following raw memory can't lead to a barrier");
682 res = mem->in(MemNode::Memory);
683 } else {
684 #ifdef ASSERT
685 mem->dump();
686 #endif
687 ShouldNotReachHere();
688 }
689 return res;
690 }
691
692 Node* ShenandoahBarrierC2Support::no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase) {
693 Node* iffproj = nullptr;
694 while (c != dom) {
695 Node* next = phase->idom(c);
696 assert(next->unique_ctrl_out_or_null() == c || c->is_Proj() || c->is_Region(), "multiple control flow out but no proj or region?");
697 if (c->is_Region()) {
698 ResourceMark rm;
699 Unique_Node_List wq;
700 wq.push(c);
701 for (uint i = 0; i < wq.size(); i++) {
702 Node *n = wq.at(i);
703 if (n == next) {
704 continue;
705 }
706 if (n->is_Region()) {
707 for (uint j = 1; j < n->req(); j++) {
708 wq.push(n->in(j));
709 }
710 } else {
711 wq.push(n->in(0));
712 }
713 }
714 for (uint i = 0; i < wq.size(); i++) {
715 Node *n = wq.at(i);
716 assert(n->is_CFG(), "");
717 if (n->is_Multi()) {
718 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
719 Node* u = n->fast_out(j);
720 if (u->is_CFG()) {
721 if (!wq.member(u) && !u->as_Proj()->is_uncommon_trap_proj()) {
722 return NodeSentinel;
723 }
724 }
725 }
726 }
727 }
728 } else if (c->is_Proj()) {
729 if (c->is_IfProj()) {
730 if (c->as_Proj()->is_uncommon_trap_if_pattern() != nullptr) {
731 // continue;
732 } else {
733 if (!allow_one_proj) {
734 return NodeSentinel;
735 }
736 if (iffproj == nullptr) {
737 iffproj = c;
738 } else {
739 return NodeSentinel;
740 }
741 }
742 } else if (c->Opcode() == Op_JumpProj) {
743 return NodeSentinel; // unsupported
744 } else if (c->Opcode() == Op_CatchProj) {
745 return NodeSentinel; // unsupported
746 } else if (c->Opcode() == Op_CProj && next->is_NeverBranch()) {
747 return NodeSentinel; // unsupported
748 } else {
749 assert(next->unique_ctrl_out() == c, "unsupported branch pattern");
750 }
751 }
752 c = next;
753 }
754 return iffproj;
755 }
756
757 Node* ShenandoahBarrierC2Support::dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase) {
758 ResourceMark rm;
759 VectorSet wq;
760 wq.set(mem->_idx);
761 mem_ctrl = phase->ctrl_or_self(mem);
762 while (!phase->is_dominator(mem_ctrl, ctrl) || mem_ctrl == ctrl) {
763 mem = next_mem(mem, alias);
764 if (wq.test_set(mem->_idx)) {
765 return nullptr;
766 }
767 mem_ctrl = phase->ctrl_or_self(mem);
768 }
769 if (mem->is_MergeMem()) {
770 mem = mem->as_MergeMem()->memory_at(alias);
771 mem_ctrl = phase->ctrl_or_self(mem);
772 }
773 return mem;
774 }
775
776 Node* ShenandoahBarrierC2Support::find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase) {
777 Node* mem = nullptr;
778 Node* c = ctrl;
779 do {
780 if (c->is_Region()) {
781 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax && mem == nullptr; i++) {
782 Node* u = c->fast_out(i);
783 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
784 if (u->adr_type() == TypePtr::BOTTOM) {
785 mem = u;
786 }
787 }
788 }
789 } else {
790 if (c->is_Call() && c->as_Call()->adr_type() != nullptr) {
791 CallProjections* projs = c->as_Call()->extract_projections(true, false);
792 if (projs->fallthrough_memproj != nullptr) {
793 if (projs->fallthrough_memproj->adr_type() == TypePtr::BOTTOM) {
794 if (projs->catchall_memproj == nullptr) {
795 mem = projs->fallthrough_memproj;
796 } else {
797 if (phase->is_dominator(projs->fallthrough_catchproj, ctrl)) {
798 mem = projs->fallthrough_memproj;
799 } else {
800 assert(phase->is_dominator(projs->catchall_catchproj, ctrl), "one proj must dominate barrier");
801 mem = projs->catchall_memproj;
802 }
803 }
804 }
805 } else {
806 Node* proj = c->as_Call()->proj_out(TypeFunc::Memory);
807 if (proj != nullptr &&
808 proj->adr_type() == TypePtr::BOTTOM) {
809 mem = proj;
810 }
811 }
812 } else {
813 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
814 Node* u = c->fast_out(i);
815 if (u->is_Proj() &&
816 u->bottom_type() == Type::MEMORY &&
817 u->adr_type() == TypePtr::BOTTOM) {
818 assert(c->is_SafePoint() || c->is_MemBar() || c->is_Start(), "");
819 assert(mem == nullptr, "only one proj");
820 mem = u;
821 }
822 }
823 assert(!c->is_Call() || c->as_Call()->adr_type() != nullptr || mem == nullptr, "no mem projection expected");
824 }
825 }
826 c = phase->idom(c);
827 } while (mem == nullptr);
828 return mem;
829 }
830
831 void ShenandoahBarrierC2Support::follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase) {
832 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
833 Node* u = n->fast_out(i);
834 if (!u->is_CFG() && phase->get_ctrl(u) == ctrl && (!u->is_Phi() || !u->in(0)->is_Loop() || u->in(LoopNode::LoopBackControl) != n)) {
835 uses.push(u);
836 }
837 }
838 }
839
840 static void hide_strip_mined_loop(OuterStripMinedLoopNode* outer, CountedLoopNode* inner, PhaseIdealLoop* phase) {
841 OuterStripMinedLoopEndNode* le = inner->outer_loop_end();
842 Node* new_outer = new LoopNode(outer->in(LoopNode::EntryControl), outer->in(LoopNode::LoopBackControl));
843 phase->register_control(new_outer, phase->get_loop(outer), outer->in(LoopNode::EntryControl));
844 Node* new_le = new IfNode(le->in(0), le->in(1), le->_prob, le->_fcnt);
845 phase->register_control(new_le, phase->get_loop(le), le->in(0));
846 phase->lazy_replace(outer, new_outer);
847 phase->lazy_replace(le, new_le);
848 inner->clear_strip_mined();
849 }
850
851 void ShenandoahBarrierC2Support::test_gc_state(Node*& ctrl, Node* raw_mem, Node*& test_fail_ctrl,
852 PhaseIdealLoop* phase, int flags) {
853 PhaseIterGVN& igvn = phase->igvn();
854 Node* old_ctrl = ctrl;
855
856 Node* thread = new ThreadLocalNode();
857 Node* gc_state_offset = igvn.MakeConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
858 Node* gc_state_addr = new AddPNode(phase->C->top(), thread, gc_state_offset);
859 Node* gc_state = new LoadBNode(old_ctrl, raw_mem, gc_state_addr,
860 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(nullptr),
861 TypeInt::BYTE, MemNode::unordered);
862 Node* gc_state_and = new AndINode(gc_state, igvn.intcon(flags));
863 Node* gc_state_cmp = new CmpINode(gc_state_and, igvn.zerocon(T_INT));
864 Node* gc_state_bool = new BoolNode(gc_state_cmp, BoolTest::ne);
865
866 IfNode* gc_state_iff = new IfNode(old_ctrl, gc_state_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
867 ctrl = new IfTrueNode(gc_state_iff);
868 test_fail_ctrl = new IfFalseNode(gc_state_iff);
869
870 IdealLoopTree* loop = phase->get_loop(old_ctrl);
871 phase->register_control(gc_state_iff, loop, old_ctrl);
872 phase->register_control(ctrl, loop, gc_state_iff);
873 phase->register_control(test_fail_ctrl, loop, gc_state_iff);
874
875 phase->register_new_node(thread, old_ctrl);
876 phase->register_new_node(gc_state_addr, old_ctrl);
877 phase->register_new_node(gc_state, old_ctrl);
878 phase->register_new_node(gc_state_and, old_ctrl);
879 phase->register_new_node(gc_state_cmp, old_ctrl);
880 phase->register_new_node(gc_state_bool, old_ctrl);
881
882 phase->set_root_as_ctrl(gc_state_offset);
883
884 assert(is_gc_state_test(gc_state_iff, flags), "Should match the shape");
885 }
886
887 void ShenandoahBarrierC2Support::test_null(Node*& ctrl, Node* val, Node*& null_ctrl, PhaseIdealLoop* phase) {
888 Node* old_ctrl = ctrl;
889 PhaseIterGVN& igvn = phase->igvn();
890
891 const Type* val_t = igvn.type(val);
892 if (val_t->meet(TypePtr::NULL_PTR) == val_t) {
893 Node* null_cmp = new CmpPNode(val, igvn.zerocon(T_OBJECT));
894 Node* null_test = new BoolNode(null_cmp, BoolTest::ne);
895
896 IfNode* null_iff = new IfNode(old_ctrl, null_test, PROB_LIKELY(0.999), COUNT_UNKNOWN);
897 ctrl = new IfTrueNode(null_iff);
898 null_ctrl = new IfFalseNode(null_iff);
899
900 IdealLoopTree* loop = phase->get_loop(old_ctrl);
901 phase->register_control(null_iff, loop, old_ctrl);
902 phase->register_control(ctrl, loop, null_iff);
903 phase->register_control(null_ctrl, loop, null_iff);
904
905 phase->register_new_node(null_cmp, old_ctrl);
906 phase->register_new_node(null_test, old_ctrl);
907 }
908 }
909
910 void ShenandoahBarrierC2Support::test_in_cset(Node*& ctrl, Node*& not_cset_ctrl, Node* val, Node* raw_mem, PhaseIdealLoop* phase) {
911 Node* old_ctrl = ctrl;
912 PhaseIterGVN& igvn = phase->igvn();
913
914 Node* raw_val = new CastP2XNode(old_ctrl, val);
915 Node* cset_idx = new URShiftXNode(raw_val, igvn.intcon(ShenandoahHeapRegion::region_size_bytes_shift_jint()));
916
917 // Figure out the target cset address with raw pointer math.
918 // This avoids matching AddP+LoadB that would emit inefficient code.
919 // See JDK-8245465.
920 Node* cset_addr_ptr = igvn.makecon(TypeRawPtr::make(ShenandoahHeap::in_cset_fast_test_addr()));
921 Node* cset_addr = new CastP2XNode(old_ctrl, cset_addr_ptr);
922 Node* cset_load_addr = new AddXNode(cset_addr, cset_idx);
923 Node* cset_load_ptr = new CastX2PNode(cset_load_addr);
924
925 Node* cset_load = new LoadBNode(old_ctrl, raw_mem, cset_load_ptr,
926 DEBUG_ONLY(phase->C->get_adr_type(Compile::AliasIdxRaw)) NOT_DEBUG(nullptr),
927 TypeInt::BYTE, MemNode::unordered);
928 Node* cset_cmp = new CmpINode(cset_load, igvn.zerocon(T_INT));
929 Node* cset_bool = new BoolNode(cset_cmp, BoolTest::ne);
930
931 IfNode* cset_iff = new IfNode(old_ctrl, cset_bool, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
932 ctrl = new IfTrueNode(cset_iff);
933 not_cset_ctrl = new IfFalseNode(cset_iff);
934
935 IdealLoopTree *loop = phase->get_loop(old_ctrl);
936 phase->register_control(cset_iff, loop, old_ctrl);
937 phase->register_control(ctrl, loop, cset_iff);
938 phase->register_control(not_cset_ctrl, loop, cset_iff);
939
940 phase->set_root_as_ctrl(cset_addr_ptr);
941
942 phase->register_new_node(raw_val, old_ctrl);
943 phase->register_new_node(cset_idx, old_ctrl);
944 phase->register_new_node(cset_addr, old_ctrl);
945 phase->register_new_node(cset_load_addr, old_ctrl);
946 phase->register_new_node(cset_load_ptr, old_ctrl);
947 phase->register_new_node(cset_load, old_ctrl);
948 phase->register_new_node(cset_cmp, old_ctrl);
949 phase->register_new_node(cset_bool, old_ctrl);
950 }
951
952 void ShenandoahBarrierC2Support::call_lrb_stub(Node*& ctrl, Node*& val, Node* load_addr,
953 DecoratorSet decorators, PhaseIdealLoop* phase) {
954 IdealLoopTree*loop = phase->get_loop(ctrl);
955 const TypePtr* obj_type = phase->igvn().type(val)->is_oopptr();
956
957 address calladdr = nullptr;
958 const char* name = nullptr;
959 bool is_strong = ShenandoahBarrierSet::is_strong_access(decorators);
960 bool is_weak = ShenandoahBarrierSet::is_weak_access(decorators);
961 bool is_phantom = ShenandoahBarrierSet::is_phantom_access(decorators);
962 bool is_native = ShenandoahBarrierSet::is_native_access(decorators);
963 bool is_narrow = UseCompressedOops && !is_native;
964 if (is_strong) {
965 if (is_narrow) {
966 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong_narrow);
967 name = "load_reference_barrier_strong_narrow";
968 } else {
969 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong);
970 name = "load_reference_barrier_strong";
971 }
972 } else if (is_weak) {
973 if (is_narrow) {
974 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak_narrow);
975 name = "load_reference_barrier_weak_narrow";
976 } else {
977 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak);
978 name = "load_reference_barrier_weak";
979 }
980 } else {
981 assert(is_phantom, "only remaining strength");
982 if (is_narrow) {
983 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom_narrow);
984 name = "load_reference_barrier_phantom_narrow";
985 } else {
986 calladdr = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom);
987 name = "load_reference_barrier_phantom";
988 }
989 }
990 Node* call = new CallLeafNode(ShenandoahBarrierSetC2::load_reference_barrier_Type(), calladdr, name, TypeRawPtr::BOTTOM);
991
992 call->init_req(TypeFunc::Control, ctrl);
993 call->init_req(TypeFunc::I_O, phase->C->top());
994 call->init_req(TypeFunc::Memory, phase->C->top());
995 call->init_req(TypeFunc::FramePtr, phase->C->top());
996 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
997 call->init_req(TypeFunc::Parms, val);
998 call->init_req(TypeFunc::Parms+1, load_addr);
999 phase->register_control(call, loop, ctrl);
1000 ctrl = new ProjNode(call, TypeFunc::Control);
1001 phase->register_control(ctrl, loop, call);
1002 val = new ProjNode(call, TypeFunc::Parms);
1003 phase->register_new_node(val, call);
1004 val = new CheckCastPPNode(ctrl, val, obj_type);
1005 phase->register_new_node(val, ctrl);
1006 }
1007
1008 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) {
1009 Node* ctrl = phase->get_ctrl(barrier);
1010 Node* init_raw_mem = fixer.find_mem(ctrl, barrier);
1011
1012 // Update the control of all nodes that should be after the
1013 // barrier control flow
1014 uses.clear();
1015 // Every node that is control dependent on the barrier's input
1016 // control will be after the expanded barrier. The raw memory (if
1017 // its memory is control dependent on the barrier's input control)
1018 // must stay above the barrier.
1019 uses_to_ignore.clear();
1020 if (phase->has_ctrl(init_raw_mem) && phase->get_ctrl(init_raw_mem) == ctrl && !init_raw_mem->is_Phi()) {
1021 uses_to_ignore.push(init_raw_mem);
1022 }
1023 for (uint next = 0; next < uses_to_ignore.size(); next++) {
1024 Node *n = uses_to_ignore.at(next);
1025 for (uint i = 0; i < n->req(); i++) {
1026 Node* in = n->in(i);
1027 if (in != nullptr && phase->has_ctrl(in) && phase->get_ctrl(in) == ctrl) {
1028 uses_to_ignore.push(in);
1029 }
1030 }
1031 }
1032 for (DUIterator_Fast imax, i = ctrl->fast_outs(imax); i < imax; i++) {
1033 Node* u = ctrl->fast_out(i);
1034 if (u->_idx < last &&
1035 u != barrier &&
1036 !u->depends_only_on_test() && // preserve dependency on test
1037 !uses_to_ignore.member(u) &&
1038 (u->in(0) != ctrl || (!u->is_Region() && !u->is_Phi())) &&
1039 (ctrl->Opcode() != Op_CatchProj || u->Opcode() != Op_CreateEx)) {
1040 Node* old_c = phase->ctrl_or_self(u);
1041 Node* c = old_c;
1042 if (c != ctrl ||
1043 is_dominator_same_ctrl(old_c, barrier, u, phase) ||
1044 ShenandoahBarrierSetC2::is_shenandoah_state_load(u)) {
1045 phase->igvn().rehash_node_delayed(u);
1046 int nb = u->replace_edge(ctrl, region, &phase->igvn());
1047 if (u->is_CFG()) {
1048 if (phase->idom(u) == ctrl) {
1049 phase->set_idom(u, region, phase->dom_depth(region));
1050 }
1051 } else if (phase->get_ctrl(u) == ctrl) {
1052 assert(u != init_raw_mem, "should leave input raw mem above the barrier");
1053 uses.push(u);
1054 }
1055 assert(nb == 1, "more than 1 ctrl input?");
1056 --i, imax -= nb;
1057 }
1058 }
1059 }
1060 }
1061
1062 static Node* create_phis_on_call_return(Node* ctrl, Node* c, Node* n, Node* n_clone, const CallProjections* projs, PhaseIdealLoop* phase) {
1063 Node* region = nullptr;
1064 while (c != ctrl) {
1065 if (c->is_Region()) {
1066 region = c;
1067 }
1068 c = phase->idom(c);
1069 }
1070 assert(region != nullptr, "");
1071 Node* phi = new PhiNode(region, n->bottom_type());
1072 for (uint j = 1; j < region->req(); j++) {
1073 Node* in = region->in(j);
1074 if (phase->is_dominator(projs->fallthrough_catchproj, in)) {
1075 phi->init_req(j, n);
1076 } else if (phase->is_dominator(projs->catchall_catchproj, in)) {
1077 phi->init_req(j, n_clone);
1078 } else {
1079 phi->init_req(j, create_phis_on_call_return(ctrl, in, n, n_clone, projs, phase));
1080 }
1081 }
1082 phase->register_new_node(phi, region);
1083 return phi;
1084 }
1085
1086 void ShenandoahBarrierC2Support::pin_and_expand(PhaseIdealLoop* phase) {
1087 ShenandoahBarrierSetC2State* state = ShenandoahBarrierSetC2::bsc2()->state();
1088
1089 Unique_Node_List uses;
1090 Node_Stack stack(0);
1091 Node_List clones;
1092 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1093 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1094
1095 Node* ctrl = phase->get_ctrl(lrb);
1096 Node* val = lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
1097
1098 CallStaticJavaNode* unc = nullptr;
1099 Node* unc_ctrl = nullptr;
1100 Node* uncasted_val = val;
1101
1102 for (DUIterator_Fast imax, i = lrb->fast_outs(imax); i < imax; i++) {
1103 Node* u = lrb->fast_out(i);
1104 if (u->Opcode() == Op_CastPP &&
1105 u->in(0) != nullptr &&
1106 phase->is_dominator(u->in(0), ctrl)) {
1107 const Type* u_t = phase->igvn().type(u);
1108
1109 if (u_t->meet(TypePtr::NULL_PTR) != u_t &&
1110 u->in(0)->Opcode() == Op_IfTrue &&
1111 u->in(0)->as_Proj()->is_uncommon_trap_if_pattern() &&
1112 u->in(0)->in(0)->is_If() &&
1113 u->in(0)->in(0)->in(1)->Opcode() == Op_Bool &&
1114 u->in(0)->in(0)->in(1)->as_Bool()->_test._test == BoolTest::ne &&
1115 u->in(0)->in(0)->in(1)->in(1)->Opcode() == Op_CmpP &&
1116 u->in(0)->in(0)->in(1)->in(1)->in(1) == val &&
1117 u->in(0)->in(0)->in(1)->in(1)->in(2)->bottom_type() == TypePtr::NULL_PTR) {
1118 IdealLoopTree* loop = phase->get_loop(ctrl);
1119 IdealLoopTree* unc_loop = phase->get_loop(u->in(0));
1120
1121 if (!unc_loop->is_member(loop)) {
1122 continue;
1123 }
1124
1125 Node* branch = no_branches(ctrl, u->in(0), false, phase);
1126 assert(branch == nullptr || branch == NodeSentinel, "was not looking for a branch");
1127 if (branch == NodeSentinel) {
1128 continue;
1129 }
1130
1131 Node* iff = u->in(0)->in(0);
1132 Node* bol = iff->in(1)->clone();
1133 Node* cmp = bol->in(1)->clone();
1134 cmp->set_req(1, lrb);
1135 bol->set_req(1, cmp);
1136 phase->igvn().replace_input_of(iff, 1, bol);
1137 phase->set_ctrl(lrb, iff->in(0));
1138 phase->register_new_node(cmp, iff->in(0));
1139 phase->register_new_node(bol, iff->in(0));
1140 break;
1141 }
1142 }
1143 }
1144 // Load barrier on the control output of a call
1145 if ((ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) || ctrl->is_CallJava()) {
1146 CallJavaNode* call = ctrl->is_Proj() ? ctrl->in(0)->as_CallJava() : ctrl->as_CallJava();
1147 if (call->entry_point() == OptoRuntime::rethrow_stub()) {
1148 // The rethrow call may have too many projections to be
1149 // properly handled here. Given there's no reason for a
1150 // barrier to depend on the call, move it above the call
1151 stack.push(lrb, 0);
1152 do {
1153 Node* n = stack.node();
1154 uint idx = stack.index();
1155 if (idx < n->req()) {
1156 Node* in = n->in(idx);
1157 stack.set_index(idx+1);
1158 if (in != nullptr) {
1159 if (phase->has_ctrl(in)) {
1160 if (phase->is_dominator(call, phase->get_ctrl(in))) {
1161 #ifdef ASSERT
1162 for (uint i = 0; i < stack.size(); i++) {
1163 assert(stack.node_at(i) != in, "node shouldn't have been seen yet");
1164 }
1165 #endif
1166 stack.push(in, 0);
1167 }
1168 } else {
1169 assert(phase->is_dominator(in, call->in(0)), "no dependency on the call");
1170 }
1171 }
1172 } else {
1173 phase->set_ctrl(n, call->in(0));
1174 stack.pop();
1175 }
1176 } while(stack.size() > 0);
1177 continue;
1178 }
1179 CallProjections* projs = call->extract_projections(false, false);
1180
1181 // If this is a runtime call, it doesn't have an exception handling path
1182 if (projs->fallthrough_catchproj == nullptr) {
1183 assert(call->method() == nullptr, "should be runtime call");
1184 assert(projs->catchall_catchproj == nullptr, "runtime call should not have catch all projection");
1185 continue;
1186 }
1187
1188 // Otherwise, clone the barrier so there's one for the fallthrough and one for the exception handling path
1189 #ifdef ASSERT
1190 VectorSet cloned;
1191 #endif
1192 Node* lrb_clone = lrb->clone();
1193 phase->register_new_node(lrb_clone, projs->catchall_catchproj);
1194 phase->set_ctrl(lrb, projs->fallthrough_catchproj);
1195
1196 stack.push(lrb, 0);
1197 clones.push(lrb_clone);
1198
1199 do {
1200 assert(stack.size() == clones.size(), "");
1201 Node* n = stack.node();
1202 #ifdef ASSERT
1203 if (n->is_Load()) {
1204 Node* mem = n->in(MemNode::Memory);
1205 for (DUIterator_Fast jmax, j = mem->fast_outs(jmax); j < jmax; j++) {
1206 Node* u = mem->fast_out(j);
1207 assert(!u->is_Store() || !u->is_LoadStore() || phase->get_ctrl(u) != ctrl, "anti dependent store?");
1208 }
1209 }
1210 #endif
1211 uint idx = stack.index();
1212 Node* n_clone = clones.at(clones.size()-1);
1213 if (idx < n->outcnt()) {
1214 Node* u = n->raw_out(idx);
1215 Node* c = phase->ctrl_or_self(u);
1216 if (phase->is_dominator(call, c) && phase->is_dominator(c, projs->fallthrough_proj)) {
1217 stack.set_index(idx+1);
1218 assert(!u->is_CFG(), "");
1219 stack.push(u, 0);
1220 assert(!cloned.test_set(u->_idx), "only one clone");
1221 Node* u_clone = u->clone();
1222 int nb = u_clone->replace_edge(n, n_clone, &phase->igvn());
1223 assert(nb > 0, "should have replaced some uses");
1224 phase->register_new_node(u_clone, projs->catchall_catchproj);
1225 clones.push(u_clone);
1226 phase->set_ctrl(u, projs->fallthrough_catchproj);
1227 } else {
1228 bool replaced = false;
1229 if (u->is_Phi()) {
1230 for (uint k = 1; k < u->req(); k++) {
1231 if (u->in(k) == n) {
1232 if (phase->is_dominator(projs->catchall_catchproj, u->in(0)->in(k))) {
1233 phase->igvn().replace_input_of(u, k, n_clone);
1234 replaced = true;
1235 } else if (!phase->is_dominator(projs->fallthrough_catchproj, u->in(0)->in(k))) {
1236 phase->igvn().replace_input_of(u, k, create_phis_on_call_return(ctrl, u->in(0)->in(k), n, n_clone, projs, phase));
1237 replaced = true;
1238 }
1239 }
1240 }
1241 } else {
1242 if (phase->is_dominator(projs->catchall_catchproj, c)) {
1243 phase->igvn().rehash_node_delayed(u);
1244 int nb = u->replace_edge(n, n_clone, &phase->igvn());
1245 assert(nb > 0, "should have replaced some uses");
1246 replaced = true;
1247 } else if (!phase->is_dominator(projs->fallthrough_catchproj, c)) {
1248 if (u->is_If()) {
1249 // Can't break If/Bool/Cmp chain
1250 assert(n->is_Bool(), "unexpected If shape");
1251 assert(stack.node_at(stack.size()-2)->is_Cmp(), "unexpected If shape");
1252 assert(n_clone->is_Bool(), "unexpected clone");
1253 assert(clones.at(clones.size()-2)->is_Cmp(), "unexpected clone");
1254 Node* bol_clone = n->clone();
1255 Node* cmp_clone = stack.node_at(stack.size()-2)->clone();
1256 bol_clone->set_req(1, cmp_clone);
1257
1258 Node* nn = stack.node_at(stack.size()-3);
1259 Node* nn_clone = clones.at(clones.size()-3);
1260 assert(nn->Opcode() == nn_clone->Opcode(), "mismatch");
1261
1262 int nb = cmp_clone->replace_edge(nn, create_phis_on_call_return(ctrl, c, nn, nn_clone, projs, phase),
1263 &phase->igvn());
1264 assert(nb > 0, "should have replaced some uses");
1265
1266 phase->register_new_node(bol_clone, u->in(0));
1267 phase->register_new_node(cmp_clone, u->in(0));
1268
1269 phase->igvn().replace_input_of(u, 1, bol_clone);
1270
1271 } else {
1272 phase->igvn().rehash_node_delayed(u);
1273 int nb = u->replace_edge(n, create_phis_on_call_return(ctrl, c, n, n_clone, projs, phase), &phase->igvn());
1274 assert(nb > 0, "should have replaced some uses");
1275 }
1276 replaced = true;
1277 }
1278 }
1279 if (!replaced) {
1280 stack.set_index(idx+1);
1281 }
1282 }
1283 } else {
1284 stack.pop();
1285 clones.pop();
1286 }
1287 } while (stack.size() > 0);
1288 assert(stack.size() == 0 && clones.size() == 0, "");
1289 }
1290 }
1291
1292 for (int i = 0; i < state->load_reference_barriers_count(); i++) {
1293 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1294 Node* ctrl = phase->get_ctrl(lrb);
1295 IdealLoopTree* loop = phase->get_loop(ctrl);
1296 Node* head = loop->head();
1297 if (head->is_OuterStripMinedLoop()) {
1298 // Expanding a barrier here will break loop strip mining
1299 // verification. Transform the loop so the loop nest doesn't
1300 // appear as strip mined.
1301 OuterStripMinedLoopNode* outer = head->as_OuterStripMinedLoop();
1302 hide_strip_mined_loop(outer, outer->unique_ctrl_out()->as_CountedLoop(), phase);
1303 }
1304 if (head->is_BaseCountedLoop() && ctrl->is_IfProj() && ctrl->in(0)->is_BaseCountedLoopEnd() &&
1305 head->as_BaseCountedLoop()->loopexit() == ctrl->in(0)) {
1306 Node* entry = head->in(LoopNode::EntryControl);
1307 Node* backedge = head->in(LoopNode::LoopBackControl);
1308 Node* new_head = new LoopNode(entry, backedge);
1309 phase->register_control(new_head, phase->get_loop(entry), entry);
1310 phase->lazy_replace(head, new_head);
1311 }
1312 }
1313
1314 // Expand load-reference-barriers
1315 MemoryGraphFixer fixer(Compile::AliasIdxRaw, true, phase);
1316 Unique_Node_List uses_to_ignore;
1317 for (int i = state->load_reference_barriers_count() - 1; i >= 0; i--) {
1318 ShenandoahLoadReferenceBarrierNode* lrb = state->load_reference_barrier(i);
1319 uint last = phase->C->unique();
1320 Node* ctrl = phase->get_ctrl(lrb);
1321 Node* val = lrb->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
1322
1323 Node* orig_ctrl = ctrl;
1324
1325 Node* raw_mem = fixer.find_mem(ctrl, lrb);
1326 Node* raw_mem_for_ctrl = fixer.find_mem(ctrl, nullptr);
1327
1328 IdealLoopTree *loop = phase->get_loop(ctrl);
1329
1330 Node* heap_stable_ctrl = nullptr;
1331 Node* null_ctrl = nullptr;
1332
1333 assert(val->bottom_type()->make_oopptr(), "need oop");
1334 assert(val->bottom_type()->make_oopptr()->const_oop() == nullptr, "expect non-constant");
1335
1336 enum { _heap_stable = 1, _evac_path, _not_cset, PATH_LIMIT };
1337 Node* region = new RegionNode(PATH_LIMIT);
1338 Node* val_phi = new PhiNode(region, val->bottom_type()->is_oopptr());
1339
1340 // Stable path.
1341 int flags = ShenandoahHeap::HAS_FORWARDED;
1342 if (!ShenandoahBarrierSet::is_strong_access(lrb->decorators())) {
1343 flags |= ShenandoahHeap::WEAK_ROOTS;
1344 }
1345 test_gc_state(ctrl, raw_mem, heap_stable_ctrl, phase, flags);
1346 IfNode* heap_stable_iff = heap_stable_ctrl->in(0)->as_If();
1347
1348 // Heap stable case
1349 region->init_req(_heap_stable, heap_stable_ctrl);
1350 val_phi->init_req(_heap_stable, val);
1351
1352 // Test for in-cset, unless it's a native-LRB. Native LRBs need to return null
1353 // even for non-cset objects to prevent resurrection of such objects.
1354 // Wires !in_cset(obj) to slot 2 of region and phis
1355 Node* not_cset_ctrl = nullptr;
1356 if (ShenandoahBarrierSet::is_strong_access(lrb->decorators())) {
1357 test_in_cset(ctrl, not_cset_ctrl, val, raw_mem, phase);
1358 }
1359 if (not_cset_ctrl != nullptr) {
1360 region->init_req(_not_cset, not_cset_ctrl);
1361 val_phi->init_req(_not_cset, val);
1362 } else {
1363 region->del_req(_not_cset);
1364 val_phi->del_req(_not_cset);
1365 }
1366
1367 // Resolve object when orig-value is in cset.
1368 // Make the unconditional resolve for fwdptr.
1369
1370 // Call lrb-stub and wire up that path in slots 4
1371 Node* result_mem = nullptr;
1372
1373 Node* addr;
1374 {
1375 VectorSet visited;
1376 addr = get_load_addr(phase, visited, lrb);
1377 }
1378 if (addr->Opcode() == Op_AddP) {
1379 Node* orig_base = addr->in(AddPNode::Base);
1380 Node* base = new CheckCastPPNode(ctrl, orig_base, orig_base->bottom_type(), ConstraintCastNode::StrongDependency);
1381 phase->register_new_node(base, ctrl);
1382 if (addr->in(AddPNode::Base) == addr->in((AddPNode::Address))) {
1383 // Field access
1384 addr = addr->clone();
1385 addr->set_req(AddPNode::Base, base);
1386 addr->set_req(AddPNode::Address, base);
1387 phase->register_new_node(addr, ctrl);
1388 } else {
1389 Node* addr2 = addr->in(AddPNode::Address);
1390 if (addr2->Opcode() == Op_AddP && addr2->in(AddPNode::Base) == addr2->in(AddPNode::Address) &&
1391 addr2->in(AddPNode::Base) == orig_base) {
1392 addr2 = addr2->clone();
1393 addr2->set_req(AddPNode::Base, base);
1394 addr2->set_req(AddPNode::Address, base);
1395 phase->register_new_node(addr2, ctrl);
1396 addr = addr->clone();
1397 addr->set_req(AddPNode::Base, base);
1398 addr->set_req(AddPNode::Address, addr2);
1399 phase->register_new_node(addr, ctrl);
1400 }
1401 }
1402 }
1403 call_lrb_stub(ctrl, val, addr, lrb->decorators(), phase);
1404 region->init_req(_evac_path, ctrl);
1405 val_phi->init_req(_evac_path, val);
1406
1407 phase->register_control(region, loop, heap_stable_iff);
1408 Node* out_val = val_phi;
1409 phase->register_new_node(val_phi, region);
1410
1411 fix_ctrl(lrb, region, fixer, uses, uses_to_ignore, last, phase);
1412
1413 ctrl = orig_ctrl;
1414
1415 phase->igvn().replace_node(lrb, out_val);
1416
1417 follow_barrier_uses(out_val, ctrl, uses, phase);
1418
1419 for(uint next = 0; next < uses.size(); next++ ) {
1420 Node *n = uses.at(next);
1421 assert(phase->get_ctrl(n) == ctrl, "bad control");
1422 assert(n != raw_mem, "should leave input raw mem above the barrier");
1423 phase->set_ctrl(n, region);
1424 follow_barrier_uses(n, ctrl, uses, phase);
1425 }
1426 fixer.record_new_ctrl(ctrl, region, raw_mem, raw_mem_for_ctrl);
1427 }
1428 // Done expanding load-reference-barriers.
1429 assert(ShenandoahBarrierSetC2::bsc2()->state()->load_reference_barriers_count() == 0, "all load reference barrier nodes should have been replaced");
1430 }
1431
1432 Node* ShenandoahBarrierC2Support::get_load_addr(PhaseIdealLoop* phase, VectorSet& visited, Node* in) {
1433 if (visited.test_set(in->_idx)) {
1434 return nullptr;
1435 }
1436 switch (in->Opcode()) {
1437 case Op_Proj:
1438 return get_load_addr(phase, visited, in->in(0));
1439 case Op_CastPP:
1440 case Op_CheckCastPP:
1441 case Op_DecodeN:
1442 case Op_EncodeP:
1443 return get_load_addr(phase, visited, in->in(1));
1444 case Op_LoadN:
1445 case Op_LoadP:
1446 return in->in(MemNode::Address);
1447 case Op_CompareAndExchangeN:
1448 case Op_CompareAndExchangeP:
1449 case Op_GetAndSetN:
1450 case Op_GetAndSetP:
1451 case Op_ShenandoahCompareAndExchangeP:
1452 case Op_ShenandoahCompareAndExchangeN:
1453 // Those instructions would just have stored a different
1454 // value into the field. No use to attempt to fix it at this point.
1455 return phase->igvn().zerocon(T_OBJECT);
1456 case Op_CMoveP:
1457 case Op_CMoveN: {
1458 Node* t = get_load_addr(phase, visited, in->in(CMoveNode::IfTrue));
1459 Node* f = get_load_addr(phase, visited, in->in(CMoveNode::IfFalse));
1460 // Handle unambiguous cases: single address reported on both branches.
1461 if (t != nullptr && f == nullptr) return t;
1462 if (t == nullptr && f != nullptr) return f;
1463 if (t != nullptr && t == f) return t;
1464 // Ambiguity.
1465 return phase->igvn().zerocon(T_OBJECT);
1466 }
1467 case Op_Phi: {
1468 Node* addr = nullptr;
1469 for (uint i = 1; i < in->req(); i++) {
1470 Node* addr1 = get_load_addr(phase, visited, in->in(i));
1471 if (addr == nullptr) {
1472 addr = addr1;
1473 }
1474 if (addr != addr1) {
1475 return phase->igvn().zerocon(T_OBJECT);
1476 }
1477 }
1478 return addr;
1479 }
1480 case Op_ShenandoahLoadReferenceBarrier:
1481 return get_load_addr(phase, visited, in->in(ShenandoahLoadReferenceBarrierNode::ValueIn));
1482 case Op_CallDynamicJava:
1483 case Op_CallLeaf:
1484 case Op_CallStaticJava:
1485 case Op_ConN:
1486 case Op_ConP:
1487 case Op_Parm:
1488 case Op_CreateEx:
1489 return phase->igvn().zerocon(T_OBJECT);
1490 default:
1491 #ifdef ASSERT
1492 fatal("Unknown node in get_load_addr: %s", NodeClassNames[in->Opcode()]);
1493 #endif
1494 return phase->igvn().zerocon(T_OBJECT);
1495 }
1496
1497 }
1498
1499 #ifdef ASSERT
1500 static bool has_never_branch(Node* root) {
1501 for (uint i = 1; i < root->req(); i++) {
1502 Node* in = root->in(i);
1503 if (in != nullptr && in->Opcode() == Op_Halt && in->in(0)->is_Proj() && in->in(0)->in(0)->is_NeverBranch()) {
1504 return true;
1505 }
1506 }
1507 return false;
1508 }
1509 #endif
1510
1511 void MemoryGraphFixer::collect_memory_nodes() {
1512 Node_Stack stack(0);
1513 VectorSet visited;
1514 Node_List regions;
1515
1516 // Walk the raw memory graph and create a mapping from CFG node to
1517 // memory node. Exclude phis for now.
1518 stack.push(_phase->C->root(), 1);
1519 do {
1520 Node* n = stack.node();
1521 int opc = n->Opcode();
1522 uint i = stack.index();
1523 if (i < n->req()) {
1524 Node* mem = nullptr;
1525 if (opc == Op_Root) {
1526 Node* in = n->in(i);
1527 int in_opc = in->Opcode();
1528 if (in_opc == Op_Return || in_opc == Op_Rethrow) {
1529 mem = in->in(TypeFunc::Memory);
1530 } else if (in_opc == Op_Halt) {
1531 if (in->in(0)->is_Region()) {
1532 Node* r = in->in(0);
1533 for (uint j = 1; j < r->req(); j++) {
1534 assert(!r->in(j)->is_NeverBranch(), "");
1535 }
1536 } else {
1537 Node* proj = in->in(0);
1538 assert(proj->is_Proj(), "");
1539 Node* in = proj->in(0);
1540 assert(in->is_CallStaticJava() || in->is_NeverBranch() || in->Opcode() == Op_Catch || proj->is_IfProj(), "");
1541 if (in->is_CallStaticJava()) {
1542 mem = in->in(TypeFunc::Memory);
1543 } else if (in->Opcode() == Op_Catch) {
1544 Node* call = in->in(0)->in(0);
1545 assert(call->is_Call(), "");
1546 mem = call->in(TypeFunc::Memory);
1547 } else if (in->is_NeverBranch()) {
1548 mem = collect_memory_for_infinite_loop(in);
1549 }
1550 }
1551 } else {
1552 #ifdef ASSERT
1553 n->dump();
1554 in->dump();
1555 #endif
1556 ShouldNotReachHere();
1557 }
1558 } else {
1559 assert(n->is_Phi() && n->bottom_type() == Type::MEMORY, "");
1560 assert(n->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(n->adr_type()) == _alias, "");
1561 mem = n->in(i);
1562 }
1563 i++;
1564 stack.set_index(i);
1565 if (mem == nullptr) {
1566 continue;
1567 }
1568 for (;;) {
1569 if (visited.test_set(mem->_idx) || mem->is_Start()) {
1570 break;
1571 }
1572 if (mem->is_Phi()) {
1573 stack.push(mem, 2);
1574 mem = mem->in(1);
1575 } else if (mem->is_Proj()) {
1576 stack.push(mem, mem->req());
1577 mem = mem->in(0);
1578 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
1579 mem = mem->in(TypeFunc::Memory);
1580 } else if (mem->is_MergeMem()) {
1581 MergeMemNode* mm = mem->as_MergeMem();
1582 mem = mm->memory_at(_alias);
1583 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
1584 assert(_alias == Compile::AliasIdxRaw, "");
1585 stack.push(mem, mem->req());
1586 mem = mem->in(MemNode::Memory);
1587 } else {
1588 #ifdef ASSERT
1589 mem->dump();
1590 #endif
1591 ShouldNotReachHere();
1592 }
1593 }
1594 } else {
1595 if (n->is_Phi()) {
1596 // Nothing
1597 } else if (!n->is_Root()) {
1598 Node* c = get_ctrl(n);
1599 _memory_nodes.map(c->_idx, n);
1600 }
1601 stack.pop();
1602 }
1603 } while(stack.is_nonempty());
1604
1605 // Iterate over CFG nodes in rpo and propagate memory state to
1606 // compute memory state at regions, creating new phis if needed.
1607 Node_List rpo_list;
1608 visited.clear();
1609 _phase->rpo(_phase->C->root(), stack, visited, rpo_list);
1610 Node* root = rpo_list.pop();
1611 assert(root == _phase->C->root(), "");
1612
1613 const bool trace = false;
1614 #ifdef ASSERT
1615 if (trace) {
1616 for (int i = rpo_list.size() - 1; i >= 0; i--) {
1617 Node* c = rpo_list.at(i);
1618 if (_memory_nodes[c->_idx] != nullptr) {
1619 tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump();
1620 }
1621 }
1622 }
1623 #endif
1624 uint last = _phase->C->unique();
1625
1626 #ifdef ASSERT
1627 uint16_t max_depth = 0;
1628 for (LoopTreeIterator iter(_phase->ltree_root()); !iter.done(); iter.next()) {
1629 IdealLoopTree* lpt = iter.current();
1630 max_depth = MAX2(max_depth, lpt->_nest);
1631 }
1632 #endif
1633
1634 bool progress = true;
1635 int iteration = 0;
1636 Node_List dead_phis;
1637 while (progress) {
1638 progress = false;
1639 iteration++;
1640 assert(iteration <= 2+max_depth || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "");
1641 if (trace) { tty->print_cr("XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"); }
1642
1643 for (int i = rpo_list.size() - 1; i >= 0; i--) {
1644 Node* c = rpo_list.at(i);
1645
1646 Node* prev_mem = _memory_nodes[c->_idx];
1647 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
1648 Node* prev_region = regions[c->_idx];
1649 Node* unique = nullptr;
1650 for (uint j = 1; j < c->req() && unique != NodeSentinel; j++) {
1651 Node* m = _memory_nodes[c->in(j)->_idx];
1652 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");
1653 if (m != nullptr) {
1654 if (m == prev_region && ((c->is_Loop() && j == LoopNode::LoopBackControl) || (prev_region->is_Phi() && prev_region->in(0) == c))) {
1655 assert((c->is_Loop() && j == LoopNode::LoopBackControl) || _phase->C->has_irreducible_loop() || has_never_branch(_phase->C->root()), "");
1656 // continue
1657 } else if (unique == nullptr) {
1658 unique = m;
1659 } else if (m == unique) {
1660 // continue
1661 } else {
1662 unique = NodeSentinel;
1663 }
1664 }
1665 }
1666 assert(unique != nullptr, "empty phi???");
1667 if (unique != NodeSentinel) {
1668 if (prev_region != nullptr && prev_region->is_Phi() && prev_region->in(0) == c) {
1669 dead_phis.push(prev_region);
1670 }
1671 regions.map(c->_idx, unique);
1672 } else {
1673 Node* phi = nullptr;
1674 if (prev_region != nullptr && prev_region->is_Phi() && prev_region->in(0) == c && prev_region->_idx >= last) {
1675 phi = prev_region;
1676 for (uint k = 1; k < c->req(); k++) {
1677 Node* m = _memory_nodes[c->in(k)->_idx];
1678 assert(m != nullptr, "expect memory state");
1679 phi->set_req(k, m);
1680 }
1681 } else {
1682 for (DUIterator_Fast jmax, j = c->fast_outs(jmax); j < jmax && phi == nullptr; j++) {
1683 Node* u = c->fast_out(j);
1684 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
1685 (u->adr_type() == TypePtr::BOTTOM || _phase->C->get_alias_index(u->adr_type()) == _alias)) {
1686 phi = u;
1687 for (uint k = 1; k < c->req() && phi != nullptr; k++) {
1688 Node* m = _memory_nodes[c->in(k)->_idx];
1689 assert(m != nullptr, "expect memory state");
1690 if (u->in(k) != m) {
1691 phi = NodeSentinel;
1692 }
1693 }
1694 }
1695 }
1696 if (phi == NodeSentinel) {
1697 phi = new PhiNode(c, Type::MEMORY, _phase->C->get_adr_type(_alias));
1698 for (uint k = 1; k < c->req(); k++) {
1699 Node* m = _memory_nodes[c->in(k)->_idx];
1700 assert(m != nullptr, "expect memory state");
1701 phi->init_req(k, m);
1702 }
1703 }
1704 }
1705 if (phi != nullptr) {
1706 regions.map(c->_idx, phi);
1707 } else {
1708 assert(c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
1709 }
1710 }
1711 Node* current_region = regions[c->_idx];
1712 if (current_region != prev_region) {
1713 progress = true;
1714 if (prev_region == prev_mem) {
1715 _memory_nodes.map(c->_idx, current_region);
1716 }
1717 }
1718 } else if (prev_mem == nullptr || prev_mem->is_Phi() || ctrl_or_self(prev_mem) != c) {
1719 Node* m = _memory_nodes[_phase->idom(c)->_idx];
1720 assert(m != nullptr || c->Opcode() == Op_Halt, "expect memory state");
1721 if (m != prev_mem) {
1722 _memory_nodes.map(c->_idx, m);
1723 progress = true;
1724 }
1725 }
1726 #ifdef ASSERT
1727 if (trace) { tty->print("X %d", c->_idx); _memory_nodes[c->_idx]->dump(); }
1728 #endif
1729 }
1730 }
1731
1732 // Replace existing phi with computed memory state for that region
1733 // if different (could be a new phi or a dominating memory node if
1734 // that phi was found to be useless).
1735 while (dead_phis.size() > 0) {
1736 Node* n = dead_phis.pop();
1737 n->replace_by(_phase->C->top());
1738 n->destruct(&_phase->igvn());
1739 }
1740 for (int i = rpo_list.size() - 1; i >= 0; i--) {
1741 Node* c = rpo_list.at(i);
1742 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
1743 Node* n = regions[c->_idx];
1744 assert(n != nullptr || c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
1745 if (n != nullptr && n->is_Phi() && n->_idx >= last && n->in(0) == c) {
1746 _phase->register_new_node(n, c);
1747 }
1748 }
1749 }
1750 for (int i = rpo_list.size() - 1; i >= 0; i--) {
1751 Node* c = rpo_list.at(i);
1752 if (c->is_Region() && (_include_lsm || !c->is_OuterStripMinedLoop())) {
1753 Node* n = regions[c->_idx];
1754 assert(n != nullptr || c->unique_ctrl_out()->Opcode() == Op_Halt, "expected memory state");
1755 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
1756 Node* u = c->fast_out(i);
1757 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
1758 u != n) {
1759 assert(c->unique_ctrl_out()->Opcode() != Op_Halt, "expected memory state");
1760 if (u->adr_type() == TypePtr::BOTTOM) {
1761 fix_memory_uses(u, n, n, c);
1762 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
1763 _phase->lazy_replace(u, n);
1764 --i; --imax;
1765 }
1766 }
1767 }
1768 }
1769 }
1770 }
1771
1772 Node* MemoryGraphFixer::collect_memory_for_infinite_loop(const Node* in) {
1773 Node* mem = nullptr;
1774 Node* head = in->in(0);
1775 assert(head->is_Region(), "unexpected infinite loop graph shape");
1776
1777 Node* phi_mem = nullptr;
1778 for (DUIterator_Fast jmax, j = head->fast_outs(jmax); j < jmax; j++) {
1779 Node* u = head->fast_out(j);
1780 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
1781 if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
1782 assert(phi_mem == nullptr || phi_mem->adr_type() == TypePtr::BOTTOM, "");
1783 phi_mem = u;
1784 } else if (u->adr_type() == TypePtr::BOTTOM) {
1785 assert(phi_mem == nullptr || _phase->C->get_alias_index(phi_mem->adr_type()) == _alias, "");
1786 if (phi_mem == nullptr) {
1787 phi_mem = u;
1788 }
1789 }
1790 }
1791 }
1792 if (phi_mem == nullptr) {
1793 ResourceMark rm;
1794 Node_Stack stack(0);
1795 stack.push(head, 1);
1796 do {
1797 Node* n = stack.node();
1798 uint i = stack.index();
1799 if (i >= n->req()) {
1800 stack.pop();
1801 } else {
1802 stack.set_index(i + 1);
1803 Node* c = n->in(i);
1804 assert(c != head, "should have found a safepoint on the way");
1805 if (stack.size() != 1 || _phase->is_dominator(head, c)) {
1806 for (;;) {
1807 if (c->is_Region()) {
1808 stack.push(c, 1);
1809 break;
1810 } else if (c->is_SafePoint() && !c->is_CallLeaf()) {
1811 Node* m = c->in(TypeFunc::Memory);
1812 if (m->is_MergeMem()) {
1813 m = m->as_MergeMem()->memory_at(_alias);
1814 }
1815 assert(mem == nullptr || mem == m, "several memory states");
1816 mem = m;
1817 break;
1818 } else {
1819 assert(c != c->in(0), "");
1820 c = c->in(0);
1821 }
1822 }
1823 }
1824 }
1825 } while (stack.size() > 0);
1826 assert(mem != nullptr, "should have found safepoint");
1827 } else {
1828 mem = phi_mem;
1829 }
1830 return mem;
1831 }
1832
1833 Node* MemoryGraphFixer::get_ctrl(Node* n) const {
1834 Node* c = _phase->get_ctrl(n);
1835 if (n->is_Proj() && n->in(0) != nullptr && n->in(0)->is_Call()) {
1836 assert(c == n->in(0), "");
1837 CallNode* call = c->as_Call();
1838 CallProjections* projs = call->extract_projections(true, false);
1839 if (projs->catchall_memproj != nullptr) {
1840 if (projs->fallthrough_memproj == n) {
1841 c = projs->fallthrough_catchproj;
1842 } else {
1843 assert(projs->catchall_memproj == n, "");
1844 c = projs->catchall_catchproj;
1845 }
1846 }
1847 }
1848 return c;
1849 }
1850
1851 Node* MemoryGraphFixer::ctrl_or_self(Node* n) const {
1852 if (_phase->has_ctrl(n))
1853 return get_ctrl(n);
1854 else {
1855 assert (n->is_CFG(), "must be a CFG node");
1856 return n;
1857 }
1858 }
1859
1860 bool MemoryGraphFixer::mem_is_valid(Node* m, Node* c) const {
1861 return m != nullptr && get_ctrl(m) == c;
1862 }
1863
1864 Node* MemoryGraphFixer::find_mem(Node* ctrl, Node* n) const {
1865 assert(n == nullptr || _phase->ctrl_or_self(n) == ctrl, "");
1866 assert(!ctrl->is_Call() || ctrl == n, "projection expected");
1867 #ifdef ASSERT
1868 if ((ctrl->is_Proj() && ctrl->in(0)->is_Call()) ||
1869 (ctrl->is_Catch() && ctrl->in(0)->in(0)->is_Call())) {
1870 CallNode* call = ctrl->is_Proj() ? ctrl->in(0)->as_Call() : ctrl->in(0)->in(0)->as_Call();
1871 int mems = 0;
1872 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) {
1873 Node* u = call->fast_out(i);
1874 if (u->bottom_type() == Type::MEMORY) {
1875 mems++;
1876 }
1877 }
1878 assert(mems <= 1, "No node right after call if multiple mem projections");
1879 }
1880 #endif
1881 Node* mem = _memory_nodes[ctrl->_idx];
1882 Node* c = ctrl;
1883 while (!mem_is_valid(mem, c) &&
1884 (!c->is_CatchProj() || mem == nullptr || c->in(0)->in(0)->in(0) != get_ctrl(mem))) {
1885 c = _phase->idom(c);
1886 mem = _memory_nodes[c->_idx];
1887 }
1888 if (n != nullptr && mem_is_valid(mem, c)) {
1889 while (!ShenandoahBarrierC2Support::is_dominator_same_ctrl(c, mem, n, _phase) && _phase->ctrl_or_self(mem) == ctrl) {
1890 mem = next_mem(mem, _alias);
1891 }
1892 if (mem->is_MergeMem()) {
1893 mem = mem->as_MergeMem()->memory_at(_alias);
1894 }
1895 if (!mem_is_valid(mem, c)) {
1896 do {
1897 c = _phase->idom(c);
1898 mem = _memory_nodes[c->_idx];
1899 } while (!mem_is_valid(mem, c) &&
1900 (!c->is_CatchProj() || mem == nullptr || c->in(0)->in(0)->in(0) != get_ctrl(mem)));
1901 }
1902 }
1903 assert(mem->bottom_type() == Type::MEMORY, "");
1904 return mem;
1905 }
1906
1907 bool MemoryGraphFixer::has_mem_phi(Node* region) const {
1908 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
1909 Node* use = region->fast_out(i);
1910 if (use->is_Phi() && use->bottom_type() == Type::MEMORY &&
1911 (_phase->C->get_alias_index(use->adr_type()) == _alias)) {
1912 return true;
1913 }
1914 }
1915 return false;
1916 }
1917
1918 void MemoryGraphFixer::fix_mem(Node* ctrl, Node* new_ctrl, Node* mem, Node* mem_for_ctrl, Node* new_mem, Unique_Node_List& uses) {
1919 assert(_phase->ctrl_or_self(new_mem) == new_ctrl, "");
1920 const bool trace = false;
1921 DEBUG_ONLY(if (trace) { tty->print("ZZZ control is"); ctrl->dump(); });
1922 DEBUG_ONLY(if (trace) { tty->print("ZZZ mem is"); mem->dump(); });
1923 GrowableArray<Node*> phis;
1924 if (mem_for_ctrl != mem) {
1925 Node* old = mem_for_ctrl;
1926 Node* prev = nullptr;
1927 while (old != mem) {
1928 prev = old;
1929 if (old->is_Store() || old->is_ClearArray() || old->is_LoadStore()) {
1930 assert(_alias == Compile::AliasIdxRaw, "");
1931 old = old->in(MemNode::Memory);
1932 } else if (old->Opcode() == Op_SCMemProj) {
1933 assert(_alias == Compile::AliasIdxRaw, "");
1934 old = old->in(0);
1935 } else {
1936 ShouldNotReachHere();
1937 }
1938 }
1939 assert(prev != nullptr, "");
1940 if (new_ctrl != ctrl) {
1941 _memory_nodes.map(ctrl->_idx, mem);
1942 _memory_nodes.map(new_ctrl->_idx, mem_for_ctrl);
1943 }
1944 uint input = (uint)MemNode::Memory;
1945 _phase->igvn().replace_input_of(prev, input, new_mem);
1946 } else {
1947 uses.clear();
1948 _memory_nodes.map(new_ctrl->_idx, new_mem);
1949 uses.push(new_ctrl);
1950 for(uint next = 0; next < uses.size(); next++ ) {
1951 Node *n = uses.at(next);
1952 assert(n->is_CFG(), "");
1953 DEBUG_ONLY(if (trace) { tty->print("ZZZ ctrl"); n->dump(); });
1954 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1955 Node* u = n->fast_out(i);
1956 if (!u->is_Root() && u->is_CFG() && u != n) {
1957 Node* m = _memory_nodes[u->_idx];
1958 if (u->is_Region() && (!u->is_OuterStripMinedLoop() || _include_lsm) &&
1959 !has_mem_phi(u) &&
1960 u->unique_ctrl_out()->Opcode() != Op_Halt) {
1961 DEBUG_ONLY(if (trace) { tty->print("ZZZ region"); u->dump(); });
1962 DEBUG_ONLY(if (trace && m != nullptr) { tty->print("ZZZ mem"); m->dump(); });
1963
1964 if (!mem_is_valid(m, u) || !m->is_Phi()) {
1965 bool push = true;
1966 bool create_phi = true;
1967 if (_phase->is_dominator(new_ctrl, u)) {
1968 create_phi = false;
1969 }
1970 if (create_phi) {
1971 Node* phi = new PhiNode(u, Type::MEMORY, _phase->C->get_adr_type(_alias));
1972 _phase->register_new_node(phi, u);
1973 phis.push(phi);
1974 DEBUG_ONLY(if (trace) { tty->print("ZZZ new phi"); phi->dump(); });
1975 if (!mem_is_valid(m, u)) {
1976 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting mem"); phi->dump(); });
1977 _memory_nodes.map(u->_idx, phi);
1978 } else {
1979 DEBUG_ONLY(if (trace) { tty->print("ZZZ NOT setting mem"); m->dump(); });
1980 for (;;) {
1981 assert(m->is_Mem() || m->is_LoadStore() || m->is_Proj(), "");
1982 Node* next = nullptr;
1983 if (m->is_Proj()) {
1984 next = m->in(0);
1985 } else {
1986 assert(m->is_Mem() || m->is_LoadStore(), "");
1987 assert(_alias == Compile::AliasIdxRaw, "");
1988 next = m->in(MemNode::Memory);
1989 }
1990 if (_phase->get_ctrl(next) != u) {
1991 break;
1992 }
1993 if (next->is_MergeMem()) {
1994 assert(_phase->get_ctrl(next->as_MergeMem()->memory_at(_alias)) != u, "");
1995 break;
1996 }
1997 if (next->is_Phi()) {
1998 assert(next->adr_type() == TypePtr::BOTTOM && next->in(0) == u, "");
1999 break;
2000 }
2001 m = next;
2002 }
2003
2004 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting to phi"); m->dump(); });
2005 assert(m->is_Mem() || m->is_LoadStore(), "");
2006 uint input = (uint)MemNode::Memory;
2007 _phase->igvn().replace_input_of(m, input, phi);
2008 push = false;
2009 }
2010 } else {
2011 DEBUG_ONLY(if (trace) { tty->print("ZZZ skipping region"); u->dump(); });
2012 }
2013 if (push) {
2014 uses.push(u);
2015 }
2016 }
2017 } else if (!mem_is_valid(m, u) &&
2018 !(u->Opcode() == Op_CProj && u->in(0)->is_NeverBranch() && u->as_Proj()->_con == 1)) {
2019 uses.push(u);
2020 }
2021 }
2022 }
2023 }
2024 for (int i = 0; i < phis.length(); i++) {
2025 Node* n = phis.at(i);
2026 Node* r = n->in(0);
2027 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi"); n->dump(); });
2028 for (uint j = 1; j < n->req(); j++) {
2029 Node* m = find_mem(r->in(j), nullptr);
2030 _phase->igvn().replace_input_of(n, j, m);
2031 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi: %d", j); m->dump(); });
2032 }
2033 }
2034 }
2035 uint last = _phase->C->unique();
2036 MergeMemNode* mm = nullptr;
2037 int alias = _alias;
2038 DEBUG_ONLY(if (trace) { tty->print("ZZZ raw mem is"); mem->dump(); });
2039 // Process loads first to not miss an anti-dependency: if the memory
2040 // edge of a store is updated before a load is processed then an
2041 // anti-dependency may be missed.
2042 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2043 Node* u = mem->out(i);
2044 if (u->_idx < last && u->is_Load() && _phase->C->get_alias_index(u->adr_type()) == alias) {
2045 Node* m = find_mem(_phase->get_ctrl(u), u);
2046 if (m != mem) {
2047 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2048 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2049 --i;
2050 }
2051 }
2052 }
2053 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2054 Node* u = mem->out(i);
2055 if (u->_idx < last) {
2056 if (u->is_Mem()) {
2057 if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2058 Node* m = find_mem(_phase->get_ctrl(u), u);
2059 if (m != mem) {
2060 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2061 _phase->igvn().replace_input_of(u, MemNode::Memory, m);
2062 --i;
2063 }
2064 }
2065 } else if (u->is_MergeMem()) {
2066 MergeMemNode* u_mm = u->as_MergeMem();
2067 if (u_mm->memory_at(alias) == mem) {
2068 MergeMemNode* newmm = nullptr;
2069 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2070 Node* uu = u->fast_out(j);
2071 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2072 if (uu->is_Phi()) {
2073 assert(uu->adr_type() == TypePtr::BOTTOM, "");
2074 Node* region = uu->in(0);
2075 int nb = 0;
2076 for (uint k = 1; k < uu->req(); k++) {
2077 if (uu->in(k) == u) {
2078 Node* m = find_mem(region->in(k), nullptr);
2079 if (m != mem) {
2080 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", k); uu->dump(); });
2081 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2082 if (newmm != u) {
2083 _phase->igvn().replace_input_of(uu, k, newmm);
2084 nb++;
2085 --jmax;
2086 }
2087 }
2088 }
2089 }
2090 if (nb > 0) {
2091 --j;
2092 }
2093 } else {
2094 Node* m = find_mem(_phase->ctrl_or_self(uu), uu);
2095 if (m != mem) {
2096 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); uu->dump(); });
2097 newmm = clone_merge_mem(u, mem, m, _phase->ctrl_or_self(m), i);
2098 if (newmm != u) {
2099 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2100 --j, --jmax;
2101 }
2102 }
2103 }
2104 }
2105 }
2106 } else if (u->is_Phi()) {
2107 assert(u->bottom_type() == Type::MEMORY, "what else?");
2108 if (_phase->C->get_alias_index(u->adr_type()) == alias || u->adr_type() == TypePtr::BOTTOM) {
2109 Node* region = u->in(0);
2110 bool replaced = false;
2111 for (uint j = 1; j < u->req(); j++) {
2112 if (u->in(j) == mem) {
2113 Node* m = find_mem(region->in(j), nullptr);
2114 Node* nnew = m;
2115 if (m != mem) {
2116 if (u->adr_type() == TypePtr::BOTTOM) {
2117 mm = allocate_merge_mem(mem, m, _phase->ctrl_or_self(m));
2118 nnew = mm;
2119 }
2120 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", j); u->dump(); });
2121 _phase->igvn().replace_input_of(u, j, nnew);
2122 replaced = true;
2123 }
2124 }
2125 }
2126 if (replaced) {
2127 --i;
2128 }
2129 }
2130 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2131 u->adr_type() == nullptr) {
2132 assert(u->adr_type() != nullptr ||
2133 u->Opcode() == Op_Rethrow ||
2134 u->Opcode() == Op_Return ||
2135 u->Opcode() == Op_SafePoint ||
2136 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2137 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2138 u->Opcode() == Op_CallLeaf, "");
2139 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2140 if (m != mem) {
2141 mm = allocate_merge_mem(mem, m, _phase->get_ctrl(m));
2142 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2143 --i;
2144 }
2145 } else if (_phase->C->get_alias_index(u->adr_type()) == alias) {
2146 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2147 if (m != mem) {
2148 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2149 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2150 --i;
2151 }
2152 } else if (u->adr_type() != TypePtr::BOTTOM &&
2153 _memory_nodes[_phase->ctrl_or_self(u)->_idx] == u) {
2154 Node* m = find_mem(_phase->ctrl_or_self(u), u);
2155 assert(m != mem, "");
2156 // u is on the wrong slice...
2157 assert(u->is_ClearArray(), "");
2158 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
2159 _phase->igvn().replace_input_of(u, u->find_edge(mem), m);
2160 --i;
2161 }
2162 }
2163 }
2164 #ifdef ASSERT
2165 assert(new_mem->outcnt() > 0, "");
2166 for (int i = 0; i < phis.length(); i++) {
2167 Node* n = phis.at(i);
2168 assert(n->outcnt() > 0, "new phi must have uses now");
2169 }
2170 #endif
2171 }
2172
2173 void MemoryGraphFixer::record_new_ctrl(Node* ctrl, Node* new_ctrl, Node* mem, Node* mem_for_ctrl) {
2174 if (mem_for_ctrl != mem && new_ctrl != ctrl) {
2175 _memory_nodes.map(ctrl->_idx, mem);
2176 _memory_nodes.map(new_ctrl->_idx, mem_for_ctrl);
2177 }
2178 }
2179
2180 MergeMemNode* MemoryGraphFixer::allocate_merge_mem(Node* mem, Node* rep_proj, Node* rep_ctrl) const {
2181 MergeMemNode* mm = MergeMemNode::make(mem);
2182 mm->set_memory_at(_alias, rep_proj);
2183 _phase->register_new_node(mm, rep_ctrl);
2184 return mm;
2185 }
2186
2187 MergeMemNode* MemoryGraphFixer::clone_merge_mem(Node* u, Node* mem, Node* rep_proj, Node* rep_ctrl, DUIterator& i) const {
2188 MergeMemNode* newmm = nullptr;
2189 MergeMemNode* u_mm = u->as_MergeMem();
2190 Node* c = _phase->get_ctrl(u);
2191 if (_phase->is_dominator(c, rep_ctrl)) {
2192 c = rep_ctrl;
2193 } else {
2194 assert(_phase->is_dominator(rep_ctrl, c), "one must dominate the other");
2195 }
2196 if (u->outcnt() == 1) {
2197 if (u->req() > (uint)_alias && u->in(_alias) == mem) {
2198 _phase->igvn().replace_input_of(u, _alias, rep_proj);
2199 --i;
2200 } else {
2201 _phase->igvn().rehash_node_delayed(u);
2202 u_mm->set_memory_at(_alias, rep_proj);
2203 }
2204 newmm = u_mm;
2205 _phase->set_ctrl_and_loop(u, c);
2206 } else {
2207 // can't simply clone u and then change one of its input because
2208 // it adds and then removes an edge which messes with the
2209 // DUIterator
2210 newmm = MergeMemNode::make(u_mm->base_memory());
2211 for (uint j = 0; j < u->req(); j++) {
2212 if (j < newmm->req()) {
2213 if (j == (uint)_alias) {
2214 newmm->set_req(j, rep_proj);
2215 } else if (newmm->in(j) != u->in(j)) {
2216 newmm->set_req(j, u->in(j));
2217 }
2218 } else if (j == (uint)_alias) {
2219 newmm->add_req(rep_proj);
2220 } else {
2221 newmm->add_req(u->in(j));
2222 }
2223 }
2224 if ((uint)_alias >= u->req()) {
2225 newmm->set_memory_at(_alias, rep_proj);
2226 }
2227 _phase->register_new_node(newmm, c);
2228 }
2229 return newmm;
2230 }
2231
2232 bool MemoryGraphFixer::should_process_phi(Node* phi) const {
2233 if (phi->adr_type() == TypePtr::BOTTOM) {
2234 Node* region = phi->in(0);
2235 for (DUIterator_Fast jmax, j = region->fast_outs(jmax); j < jmax; j++) {
2236 Node* uu = region->fast_out(j);
2237 if (uu->is_Phi() && uu != phi && uu->bottom_type() == Type::MEMORY && _phase->C->get_alias_index(uu->adr_type()) == _alias) {
2238 return false;
2239 }
2240 }
2241 return true;
2242 }
2243 return _phase->C->get_alias_index(phi->adr_type()) == _alias;
2244 }
2245
2246 void MemoryGraphFixer::fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl) const {
2247 uint last = _phase-> C->unique();
2248 MergeMemNode* mm = nullptr;
2249 assert(mem->bottom_type() == Type::MEMORY, "");
2250 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
2251 Node* u = mem->out(i);
2252 if (u != replacement && u->_idx < last) {
2253 if (u->is_MergeMem()) {
2254 MergeMemNode* u_mm = u->as_MergeMem();
2255 if (u_mm->memory_at(_alias) == mem) {
2256 MergeMemNode* newmm = nullptr;
2257 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
2258 Node* uu = u->fast_out(j);
2259 assert(!uu->is_MergeMem(), "chain of MergeMems?");
2260 if (uu->is_Phi()) {
2261 if (should_process_phi(uu)) {
2262 Node* region = uu->in(0);
2263 int nb = 0;
2264 for (uint k = 1; k < uu->req(); k++) {
2265 if (uu->in(k) == u && _phase->is_dominator(rep_ctrl, region->in(k))) {
2266 if (newmm == nullptr) {
2267 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2268 }
2269 if (newmm != u) {
2270 _phase->igvn().replace_input_of(uu, k, newmm);
2271 nb++;
2272 --jmax;
2273 }
2274 }
2275 }
2276 if (nb > 0) {
2277 --j;
2278 }
2279 }
2280 } else {
2281 if (rep_ctrl != uu && ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(uu), replacement, uu, _phase)) {
2282 if (newmm == nullptr) {
2283 newmm = clone_merge_mem(u, mem, rep_proj, rep_ctrl, i);
2284 }
2285 if (newmm != u) {
2286 _phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
2287 --j, --jmax;
2288 }
2289 }
2290 }
2291 }
2292 }
2293 } else if (u->is_Phi()) {
2294 assert(u->bottom_type() == Type::MEMORY, "what else?");
2295 Node* region = u->in(0);
2296 if (should_process_phi(u)) {
2297 bool replaced = false;
2298 for (uint j = 1; j < u->req(); j++) {
2299 if (u->in(j) == mem && _phase->is_dominator(rep_ctrl, region->in(j))) {
2300 Node* nnew = rep_proj;
2301 if (u->adr_type() == TypePtr::BOTTOM) {
2302 if (mm == nullptr) {
2303 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2304 }
2305 nnew = mm;
2306 }
2307 _phase->igvn().replace_input_of(u, j, nnew);
2308 replaced = true;
2309 }
2310 }
2311 if (replaced) {
2312 --i;
2313 }
2314
2315 }
2316 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
2317 u->adr_type() == nullptr) {
2318 assert(u->adr_type() != nullptr ||
2319 u->Opcode() == Op_Rethrow ||
2320 u->Opcode() == Op_Return ||
2321 u->Opcode() == Op_SafePoint ||
2322 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
2323 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
2324 u->Opcode() == Op_CallLeaf, "%s", u->Name());
2325 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2326 if (mm == nullptr) {
2327 mm = allocate_merge_mem(mem, rep_proj, rep_ctrl);
2328 }
2329 _phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
2330 --i;
2331 }
2332 } else if (_phase->C->get_alias_index(u->adr_type()) == _alias) {
2333 if (ShenandoahBarrierC2Support::is_dominator(rep_ctrl, _phase->ctrl_or_self(u), replacement, u, _phase)) {
2334 _phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
2335 --i;
2336 }
2337 }
2338 }
2339 }
2340 }
2341
2342 ShenandoahLoadReferenceBarrierNode::ShenandoahLoadReferenceBarrierNode(Node* ctrl, Node* obj, DecoratorSet decorators)
2343 : Node(ctrl, obj), _decorators(decorators) {
2344 ShenandoahBarrierSetC2::bsc2()->state()->add_load_reference_barrier(this);
2345 }
2346
2347 DecoratorSet ShenandoahLoadReferenceBarrierNode::decorators() const {
2348 return _decorators;
2349 }
2350
2351 uint ShenandoahLoadReferenceBarrierNode::size_of() const {
2352 return sizeof(*this);
2353 }
2354
2355 static DecoratorSet mask_decorators(DecoratorSet decorators) {
2356 return decorators & (ON_STRONG_OOP_REF | ON_WEAK_OOP_REF | ON_PHANTOM_OOP_REF | ON_UNKNOWN_OOP_REF | IN_NATIVE);
2357 }
2358
2359 uint ShenandoahLoadReferenceBarrierNode::hash() const {
2360 uint hash = Node::hash();
2361 hash += mask_decorators(_decorators);
2362 return hash;
2363 }
2364
2365 bool ShenandoahLoadReferenceBarrierNode::cmp( const Node &n ) const {
2366 return Node::cmp(n) && n.Opcode() == Op_ShenandoahLoadReferenceBarrier &&
2367 mask_decorators(_decorators) == mask_decorators(((const ShenandoahLoadReferenceBarrierNode&)n)._decorators);
2368 }
2369
2370 const Type* ShenandoahLoadReferenceBarrierNode::bottom_type() const {
2371 if (in(ValueIn) == nullptr || in(ValueIn)->is_top()) {
2372 return Type::TOP;
2373 }
2374 const Type* t = in(ValueIn)->bottom_type();
2375 if (t == TypePtr::NULL_PTR) {
2376 return t;
2377 }
2378
2379 if (ShenandoahBarrierSet::is_strong_access(decorators())) {
2380 return t;
2381 }
2382
2383 return t->meet(TypePtr::NULL_PTR);
2384 }
2385
2386 const Type* ShenandoahLoadReferenceBarrierNode::Value(PhaseGVN* phase) const {
2387 // Either input is TOP ==> the result is TOP
2388 const Type *t2 = phase->type(in(ValueIn));
2389 if( t2 == Type::TOP ) return Type::TOP;
2390
2391 if (t2 == TypePtr::NULL_PTR) {
2392 return t2;
2393 }
2394
2395 if (ShenandoahBarrierSet::is_strong_access(decorators())) {
2396 return t2;
2397 }
2398
2399 return t2->meet(TypePtr::NULL_PTR);
2400 }
2401
2402 Node* ShenandoahLoadReferenceBarrierNode::Identity(PhaseGVN* phase) {
2403 Node* value = in(ValueIn);
2404 if (!needs_barrier(phase, value)) {
2405 return value;
2406 }
2407 return this;
2408 }
2409
2410 bool ShenandoahLoadReferenceBarrierNode::needs_barrier(PhaseGVN* phase, Node* n) {
2411 Unique_Node_List visited;
2412 return needs_barrier_impl(phase, n, visited);
2413 }
2414
2415 bool ShenandoahLoadReferenceBarrierNode::needs_barrier_impl(PhaseGVN* phase, Node* n, Unique_Node_List &visited) {
2416 if (n == nullptr) return false;
2417 if (visited.member(n)) {
2418 return false; // Been there.
2419 }
2420 visited.push(n);
2421
2422 if (n->is_Allocate()) {
2423 // tty->print_cr("optimize barrier on alloc");
2424 return false;
2425 }
2426 if (n->is_Call()) {
2427 // tty->print_cr("optimize barrier on call");
2428 return false;
2429 }
2430
2431 const Type* type = phase->type(n);
2432 if (type == Type::TOP) {
2433 return false;
2434 }
2435 if (type->make_ptr()->higher_equal(TypePtr::NULL_PTR)) {
2436 // tty->print_cr("optimize barrier on null");
2437 return false;
2438 }
2439 if (type->make_oopptr() && type->make_oopptr()->const_oop() != nullptr) {
2440 // tty->print_cr("optimize barrier on constant");
2441 return false;
2442 }
2443
2444 switch (n->Opcode()) {
2445 case Op_AddP:
2446 return true; // TODO: Can refine?
2447 case Op_LoadP:
2448 case Op_ShenandoahCompareAndExchangeN:
2449 case Op_ShenandoahCompareAndExchangeP:
2450 case Op_CompareAndExchangeN:
2451 case Op_CompareAndExchangeP:
2452 case Op_GetAndSetN:
2453 case Op_GetAndSetP:
2454 return true;
2455 case Op_Phi: {
2456 for (uint i = 1; i < n->req(); i++) {
2457 if (needs_barrier_impl(phase, n->in(i), visited)) return true;
2458 }
2459 return false;
2460 }
2461 case Op_CheckCastPP:
2462 case Op_CastPP:
2463 return needs_barrier_impl(phase, n->in(1), visited);
2464 case Op_Proj:
2465 return needs_barrier_impl(phase, n->in(0), visited);
2466 case Op_ShenandoahLoadReferenceBarrier:
2467 // tty->print_cr("optimize barrier on barrier");
2468 return false;
2469 case Op_Parm:
2470 // tty->print_cr("optimize barrier on input arg");
2471 return false;
2472 case Op_DecodeN:
2473 case Op_EncodeP:
2474 return needs_barrier_impl(phase, n->in(1), visited);
2475 case Op_LoadN:
2476 return true;
2477 case Op_CMoveN:
2478 case Op_CMoveP:
2479 return needs_barrier_impl(phase, n->in(2), visited) ||
2480 needs_barrier_impl(phase, n->in(3), visited);
2481 case Op_CreateEx:
2482 return false;
2483 default:
2484 break;
2485 }
2486 #ifdef ASSERT
2487 tty->print("need barrier on?: ");
2488 tty->print_cr("ins:");
2489 n->dump(2);
2490 tty->print_cr("outs:");
2491 n->dump(-2);
2492 ShouldNotReachHere();
2493 #endif
2494 return true;
2495 }