Tue, 18 Jun 2013 12:31:07 -0700
8015237: Parallelize string table scanning during strong root processing
Summary: Parallelize the scanning of the intern string table by having each GC worker claim a given number of buckets. Changes were also reviewed by Per Liden <per.liden@oracle.com>.
Reviewed-by: tschatzl, stefank, twisti
1 /*
2 * Copyright (c) 1999, 2012, Oracle and/or its affiliates. All rights reserved.
3 * Copyright 2008, 2009, 2010 Red Hat, Inc.
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 */
26 #include "precompiled.hpp"
27 #include "ci/ciField.hpp"
28 #include "ci/ciInstance.hpp"
29 #include "ci/ciObjArrayKlass.hpp"
30 #include "ci/ciStreams.hpp"
31 #include "ci/ciType.hpp"
32 #include "ci/ciTypeFlow.hpp"
33 #include "interpreter/bytecodes.hpp"
34 #include "memory/allocation.hpp"
35 #include "runtime/deoptimization.hpp"
36 #include "shark/llvmHeaders.hpp"
37 #include "shark/llvmValue.hpp"
38 #include "shark/sharkBuilder.hpp"
39 #include "shark/sharkCacheDecache.hpp"
40 #include "shark/sharkConstant.hpp"
41 #include "shark/sharkInliner.hpp"
42 #include "shark/sharkState.hpp"
43 #include "shark/sharkTopLevelBlock.hpp"
44 #include "shark/sharkValue.hpp"
45 #include "shark/shark_globals.hpp"
46 #include "utilities/debug.hpp"
48 using namespace llvm;
50 void SharkTopLevelBlock::scan_for_traps() {
51 // If typeflow found a trap then don't scan past it
52 int limit_bci = ciblock()->has_trap() ? ciblock()->trap_bci() : limit();
54 // Scan the bytecode for traps that are always hit
55 iter()->reset_to_bci(start());
56 while (iter()->next_bci() < limit_bci) {
57 iter()->next();
59 ciField *field;
60 ciMethod *method;
61 ciInstanceKlass *klass;
62 bool will_link;
63 bool is_field;
65 switch (bc()) {
66 case Bytecodes::_ldc:
67 case Bytecodes::_ldc_w:
68 case Bytecodes::_ldc2_w:
69 if (!SharkConstant::for_ldc(iter())->is_loaded()) {
70 set_trap(
71 Deoptimization::make_trap_request(
72 Deoptimization::Reason_uninitialized,
73 Deoptimization::Action_reinterpret), bci());
74 return;
75 }
76 break;
78 case Bytecodes::_getfield:
79 case Bytecodes::_getstatic:
80 case Bytecodes::_putfield:
81 case Bytecodes::_putstatic:
82 field = iter()->get_field(will_link);
83 assert(will_link, "typeflow responsibility");
84 is_field = (bc() == Bytecodes::_getfield || bc() == Bytecodes::_putfield);
86 // If the bytecode does not match the field then bail out to
87 // the interpreter to throw an IncompatibleClassChangeError
88 if (is_field == field->is_static()) {
89 set_trap(
90 Deoptimization::make_trap_request(
91 Deoptimization::Reason_unhandled,
92 Deoptimization::Action_none), bci());
93 return;
94 }
96 // Bail out if we are trying to access a static variable
97 // before the class initializer has completed.
98 if (!is_field && !field->holder()->is_initialized()) {
99 if (!static_field_ok_in_clinit(field)) {
100 set_trap(
101 Deoptimization::make_trap_request(
102 Deoptimization::Reason_uninitialized,
103 Deoptimization::Action_reinterpret), bci());
104 return;
105 }
106 }
107 break;
109 case Bytecodes::_invokestatic:
110 case Bytecodes::_invokespecial:
111 case Bytecodes::_invokevirtual:
112 case Bytecodes::_invokeinterface:
113 ciSignature* sig;
114 method = iter()->get_method(will_link, &sig);
115 assert(will_link, "typeflow responsibility");
116 // We can't compile calls to method handle intrinsics, because we use
117 // the interpreter entry points and they expect the top frame to be an
118 // interpreter frame. We need to implement the intrinsics for Shark.
119 if (method->is_method_handle_intrinsic() || method->is_compiled_lambda_form()) {
120 if (SharkPerformanceWarnings) {
121 warning("JSR292 optimization not yet implemented in Shark");
122 }
123 set_trap(
124 Deoptimization::make_trap_request(
125 Deoptimization::Reason_unhandled,
126 Deoptimization::Action_make_not_compilable), bci());
127 return;
128 }
129 if (!method->holder()->is_linked()) {
130 set_trap(
131 Deoptimization::make_trap_request(
132 Deoptimization::Reason_uninitialized,
133 Deoptimization::Action_reinterpret), bci());
134 return;
135 }
137 if (bc() == Bytecodes::_invokevirtual) {
138 klass = ciEnv::get_instance_klass_for_declared_method_holder(
139 iter()->get_declared_method_holder());
140 if (!klass->is_linked()) {
141 set_trap(
142 Deoptimization::make_trap_request(
143 Deoptimization::Reason_uninitialized,
144 Deoptimization::Action_reinterpret), bci());
145 return;
146 }
147 }
148 break;
150 case Bytecodes::_new:
151 klass = iter()->get_klass(will_link)->as_instance_klass();
152 assert(will_link, "typeflow responsibility");
154 // Bail out if the class is unloaded
155 if (iter()->is_unresolved_klass() || !klass->is_initialized()) {
156 set_trap(
157 Deoptimization::make_trap_request(
158 Deoptimization::Reason_uninitialized,
159 Deoptimization::Action_reinterpret), bci());
160 return;
161 }
163 // Bail out if the class cannot be instantiated
164 if (klass->is_abstract() || klass->is_interface() ||
165 klass->name() == ciSymbol::java_lang_Class()) {
166 set_trap(
167 Deoptimization::make_trap_request(
168 Deoptimization::Reason_unhandled,
169 Deoptimization::Action_reinterpret), bci());
170 return;
171 }
172 break;
173 case Bytecodes::_invokedynamic:
174 case Bytecodes::_invokehandle:
175 if (SharkPerformanceWarnings) {
176 warning("JSR292 optimization not yet implemented in Shark");
177 }
178 set_trap(
179 Deoptimization::make_trap_request(
180 Deoptimization::Reason_unhandled,
181 Deoptimization::Action_make_not_compilable), bci());
182 return;
183 }
184 }
186 // Trap if typeflow trapped (and we didn't before)
187 if (ciblock()->has_trap()) {
188 set_trap(
189 Deoptimization::make_trap_request(
190 Deoptimization::Reason_unloaded,
191 Deoptimization::Action_reinterpret,
192 ciblock()->trap_index()), ciblock()->trap_bci());
193 return;
194 }
195 }
197 bool SharkTopLevelBlock::static_field_ok_in_clinit(ciField* field) {
198 assert(field->is_static(), "should be");
200 // This code is lifted pretty much verbatim from C2's
201 // Parse::static_field_ok_in_clinit() in parse3.cpp.
202 bool access_OK = false;
203 if (target()->holder()->is_subclass_of(field->holder())) {
204 if (target()->is_static()) {
205 if (target()->name() == ciSymbol::class_initializer_name()) {
206 // It's OK to access static fields from the class initializer
207 access_OK = true;
208 }
209 }
210 else {
211 if (target()->name() == ciSymbol::object_initializer_name()) {
212 // It's also OK to access static fields inside a constructor,
213 // because any thread calling the constructor must first have
214 // synchronized on the class by executing a "new" bytecode.
215 access_OK = true;
216 }
217 }
218 }
219 return access_OK;
220 }
222 SharkState* SharkTopLevelBlock::entry_state() {
223 if (_entry_state == NULL) {
224 assert(needs_phis(), "should do");
225 _entry_state = new SharkPHIState(this);
226 }
227 return _entry_state;
228 }
230 void SharkTopLevelBlock::add_incoming(SharkState* incoming_state) {
231 if (needs_phis()) {
232 ((SharkPHIState *) entry_state())->add_incoming(incoming_state);
233 }
234 else if (_entry_state == NULL) {
235 _entry_state = incoming_state;
236 }
237 else {
238 assert(entry_state()->equal_to(incoming_state), "should be");
239 }
240 }
242 void SharkTopLevelBlock::enter(SharkTopLevelBlock* predecessor,
243 bool is_exception) {
244 // This block requires phis:
245 // - if it is entered more than once
246 // - if it is an exception handler, because in which
247 // case we assume it's entered more than once.
248 // - if the predecessor will be compiled after this
249 // block, in which case we can't simple propagate
250 // the state forward.
251 if (!needs_phis() &&
252 (entered() ||
253 is_exception ||
254 (predecessor && predecessor->index() >= index())))
255 _needs_phis = true;
257 // Recurse into the tree
258 if (!entered()) {
259 _entered = true;
261 scan_for_traps();
262 if (!has_trap()) {
263 for (int i = 0; i < num_successors(); i++) {
264 successor(i)->enter(this, false);
265 }
266 }
267 compute_exceptions();
268 for (int i = 0; i < num_exceptions(); i++) {
269 SharkTopLevelBlock *handler = exception(i);
270 if (handler)
271 handler->enter(this, true);
272 }
273 }
274 }
276 void SharkTopLevelBlock::initialize() {
277 char name[28];
278 snprintf(name, sizeof(name),
279 "bci_%d%s",
280 start(), is_backedge_copy() ? "_backedge_copy" : "");
281 _entry_block = function()->CreateBlock(name);
282 }
284 void SharkTopLevelBlock::decache_for_Java_call(ciMethod *callee) {
285 SharkJavaCallDecacher(function(), bci(), callee).scan(current_state());
286 for (int i = 0; i < callee->arg_size(); i++)
287 xpop();
288 }
290 void SharkTopLevelBlock::cache_after_Java_call(ciMethod *callee) {
291 if (callee->return_type()->size()) {
292 ciType *type;
293 switch (callee->return_type()->basic_type()) {
294 case T_BOOLEAN:
295 case T_BYTE:
296 case T_CHAR:
297 case T_SHORT:
298 type = ciType::make(T_INT);
299 break;
301 default:
302 type = callee->return_type();
303 }
305 push(SharkValue::create_generic(type, NULL, false));
306 }
307 SharkJavaCallCacher(function(), callee).scan(current_state());
308 }
310 void SharkTopLevelBlock::decache_for_VM_call() {
311 SharkVMCallDecacher(function(), bci()).scan(current_state());
312 }
314 void SharkTopLevelBlock::cache_after_VM_call() {
315 SharkVMCallCacher(function()).scan(current_state());
316 }
318 void SharkTopLevelBlock::decache_for_trap() {
319 SharkTrapDecacher(function(), bci()).scan(current_state());
320 }
322 void SharkTopLevelBlock::emit_IR() {
323 builder()->SetInsertPoint(entry_block());
325 // Parse the bytecode
326 parse_bytecode(start(), limit());
328 // If this block falls through to the next then it won't have been
329 // terminated by a bytecode and we have to add the branch ourselves
330 if (falls_through() && !has_trap())
331 do_branch(ciTypeFlow::FALL_THROUGH);
332 }
334 SharkTopLevelBlock* SharkTopLevelBlock::bci_successor(int bci) const {
335 // XXX now with Linear Search Technology (tm)
336 for (int i = 0; i < num_successors(); i++) {
337 ciTypeFlow::Block *successor = ciblock()->successors()->at(i);
338 if (successor->start() == bci)
339 return function()->block(successor->pre_order());
340 }
341 ShouldNotReachHere();
342 }
344 void SharkTopLevelBlock::do_zero_check(SharkValue *value) {
345 if (value->is_phi() && value->as_phi()->all_incomers_zero_checked()) {
346 function()->add_deferred_zero_check(this, value);
347 }
348 else {
349 BasicBlock *continue_block = function()->CreateBlock("not_zero");
350 SharkState *saved_state = current_state();
351 set_current_state(saved_state->copy());
352 zero_check_value(value, continue_block);
353 builder()->SetInsertPoint(continue_block);
354 set_current_state(saved_state);
355 }
357 value->set_zero_checked(true);
358 }
360 void SharkTopLevelBlock::do_deferred_zero_check(SharkValue* value,
361 int bci,
362 SharkState* saved_state,
363 BasicBlock* continue_block) {
364 if (value->as_phi()->all_incomers_zero_checked()) {
365 builder()->CreateBr(continue_block);
366 }
367 else {
368 iter()->force_bci(start());
369 set_current_state(saved_state);
370 zero_check_value(value, continue_block);
371 }
372 }
374 void SharkTopLevelBlock::zero_check_value(SharkValue* value,
375 BasicBlock* continue_block) {
376 BasicBlock *zero_block = builder()->CreateBlock(continue_block, "zero");
378 Value *a, *b;
379 switch (value->basic_type()) {
380 case T_BYTE:
381 case T_CHAR:
382 case T_SHORT:
383 case T_INT:
384 a = value->jint_value();
385 b = LLVMValue::jint_constant(0);
386 break;
387 case T_LONG:
388 a = value->jlong_value();
389 b = LLVMValue::jlong_constant(0);
390 break;
391 case T_OBJECT:
392 case T_ARRAY:
393 a = value->jobject_value();
394 b = LLVMValue::LLVMValue::null();
395 break;
396 default:
397 tty->print_cr("Unhandled type %s", type2name(value->basic_type()));
398 ShouldNotReachHere();
399 }
401 builder()->CreateCondBr(
402 builder()->CreateICmpNE(a, b), continue_block, zero_block);
404 builder()->SetInsertPoint(zero_block);
405 if (value->is_jobject()) {
406 call_vm(
407 builder()->throw_NullPointerException(),
408 builder()->CreateIntToPtr(
409 LLVMValue::intptr_constant((intptr_t) __FILE__),
410 PointerType::getUnqual(SharkType::jbyte_type())),
411 LLVMValue::jint_constant(__LINE__),
412 EX_CHECK_NONE);
413 }
414 else {
415 call_vm(
416 builder()->throw_ArithmeticException(),
417 builder()->CreateIntToPtr(
418 LLVMValue::intptr_constant((intptr_t) __FILE__),
419 PointerType::getUnqual(SharkType::jbyte_type())),
420 LLVMValue::jint_constant(__LINE__),
421 EX_CHECK_NONE);
422 }
424 Value *pending_exception = get_pending_exception();
425 clear_pending_exception();
426 handle_exception(pending_exception, EX_CHECK_FULL);
427 }
429 void SharkTopLevelBlock::check_bounds(SharkValue* array, SharkValue* index) {
430 BasicBlock *out_of_bounds = function()->CreateBlock("out_of_bounds");
431 BasicBlock *in_bounds = function()->CreateBlock("in_bounds");
433 Value *length = builder()->CreateArrayLength(array->jarray_value());
434 // we use an unsigned comparison to catch negative values
435 builder()->CreateCondBr(
436 builder()->CreateICmpULT(index->jint_value(), length),
437 in_bounds, out_of_bounds);
439 builder()->SetInsertPoint(out_of_bounds);
440 SharkState *saved_state = current_state()->copy();
442 call_vm(
443 builder()->throw_ArrayIndexOutOfBoundsException(),
444 builder()->CreateIntToPtr(
445 LLVMValue::intptr_constant((intptr_t) __FILE__),
446 PointerType::getUnqual(SharkType::jbyte_type())),
447 LLVMValue::jint_constant(__LINE__),
448 index->jint_value(),
449 EX_CHECK_NONE);
451 Value *pending_exception = get_pending_exception();
452 clear_pending_exception();
453 handle_exception(pending_exception, EX_CHECK_FULL);
455 set_current_state(saved_state);
457 builder()->SetInsertPoint(in_bounds);
458 }
460 void SharkTopLevelBlock::check_pending_exception(int action) {
461 assert(action & EAM_CHECK, "should be");
463 BasicBlock *exception = function()->CreateBlock("exception");
464 BasicBlock *no_exception = function()->CreateBlock("no_exception");
466 Value *pending_exception = get_pending_exception();
467 builder()->CreateCondBr(
468 builder()->CreateICmpEQ(pending_exception, LLVMValue::null()),
469 no_exception, exception);
471 builder()->SetInsertPoint(exception);
472 SharkState *saved_state = current_state()->copy();
473 if (action & EAM_MONITOR_FUDGE) {
474 // The top monitor is marked live, but the exception was thrown
475 // while setting it up so we need to mark it dead before we enter
476 // any exception handlers as they will not expect it to be there.
477 set_num_monitors(num_monitors() - 1);
478 action ^= EAM_MONITOR_FUDGE;
479 }
480 clear_pending_exception();
481 handle_exception(pending_exception, action);
482 set_current_state(saved_state);
484 builder()->SetInsertPoint(no_exception);
485 }
487 void SharkTopLevelBlock::compute_exceptions() {
488 ciExceptionHandlerStream str(target(), start());
490 int exc_count = str.count();
491 _exc_handlers = new GrowableArray<ciExceptionHandler*>(exc_count);
492 _exceptions = new GrowableArray<SharkTopLevelBlock*>(exc_count);
494 int index = 0;
495 for (; !str.is_done(); str.next()) {
496 ciExceptionHandler *handler = str.handler();
497 if (handler->handler_bci() == -1)
498 break;
499 _exc_handlers->append(handler);
501 // Try and get this exception's handler from typeflow. We should
502 // do it this way always, really, except that typeflow sometimes
503 // doesn't record exceptions, even loaded ones, and sometimes it
504 // returns them with a different handler bci. Why???
505 SharkTopLevelBlock *block = NULL;
506 ciInstanceKlass* klass;
507 if (handler->is_catch_all()) {
508 klass = java_lang_Throwable_klass();
509 }
510 else {
511 klass = handler->catch_klass();
512 }
513 for (int i = 0; i < ciblock()->exceptions()->length(); i++) {
514 if (klass == ciblock()->exc_klasses()->at(i)) {
515 block = function()->block(ciblock()->exceptions()->at(i)->pre_order());
516 if (block->start() == handler->handler_bci())
517 break;
518 else
519 block = NULL;
520 }
521 }
523 // If typeflow let us down then try and figure it out ourselves
524 if (block == NULL) {
525 for (int i = 0; i < function()->block_count(); i++) {
526 SharkTopLevelBlock *candidate = function()->block(i);
527 if (candidate->start() == handler->handler_bci()) {
528 if (block != NULL) {
529 NOT_PRODUCT(warning("there may be trouble ahead"));
530 block = NULL;
531 break;
532 }
533 block = candidate;
534 }
535 }
536 }
537 _exceptions->append(block);
538 }
539 }
541 void SharkTopLevelBlock::handle_exception(Value* exception, int action) {
542 if (action & EAM_HANDLE && num_exceptions() != 0) {
543 // Clear the stack and push the exception onto it
544 while (xstack_depth())
545 pop();
546 push(SharkValue::create_jobject(exception, true));
548 // Work out how many options we have to check
549 bool has_catch_all = exc_handler(num_exceptions() - 1)->is_catch_all();
550 int num_options = num_exceptions();
551 if (has_catch_all)
552 num_options--;
554 // Marshal any non-catch-all handlers
555 if (num_options > 0) {
556 bool all_loaded = true;
557 for (int i = 0; i < num_options; i++) {
558 if (!exc_handler(i)->catch_klass()->is_loaded()) {
559 all_loaded = false;
560 break;
561 }
562 }
564 if (all_loaded)
565 marshal_exception_fast(num_options);
566 else
567 marshal_exception_slow(num_options);
568 }
570 // Install the catch-all handler, if present
571 if (has_catch_all) {
572 SharkTopLevelBlock* handler = this->exception(num_options);
573 assert(handler != NULL, "catch-all handler cannot be unloaded");
575 builder()->CreateBr(handler->entry_block());
576 handler->add_incoming(current_state());
577 return;
578 }
579 }
581 // No exception handler was found; unwind and return
582 handle_return(T_VOID, exception);
583 }
585 void SharkTopLevelBlock::marshal_exception_fast(int num_options) {
586 Value *exception_klass = builder()->CreateValueOfStructEntry(
587 xstack(0)->jobject_value(),
588 in_ByteSize(oopDesc::klass_offset_in_bytes()),
589 SharkType::klass_type(),
590 "exception_klass");
592 for (int i = 0; i < num_options; i++) {
593 Value *check_klass =
594 builder()->CreateInlineMetadata(exc_handler(i)->catch_klass(), SharkType::klass_type());
596 BasicBlock *not_exact = function()->CreateBlock("not_exact");
597 BasicBlock *not_subtype = function()->CreateBlock("not_subtype");
599 builder()->CreateCondBr(
600 builder()->CreateICmpEQ(check_klass, exception_klass),
601 handler_for_exception(i), not_exact);
603 builder()->SetInsertPoint(not_exact);
604 builder()->CreateCondBr(
605 builder()->CreateICmpNE(
606 builder()->CreateCall2(
607 builder()->is_subtype_of(), check_klass, exception_klass),
608 LLVMValue::jbyte_constant(0)),
609 handler_for_exception(i), not_subtype);
611 builder()->SetInsertPoint(not_subtype);
612 }
613 }
615 void SharkTopLevelBlock::marshal_exception_slow(int num_options) {
616 int *indexes = NEW_RESOURCE_ARRAY(int, num_options);
617 for (int i = 0; i < num_options; i++)
618 indexes[i] = exc_handler(i)->catch_klass_index();
620 Value *index = call_vm(
621 builder()->find_exception_handler(),
622 builder()->CreateInlineData(
623 indexes,
624 num_options * sizeof(int),
625 PointerType::getUnqual(SharkType::jint_type())),
626 LLVMValue::jint_constant(num_options),
627 EX_CHECK_NO_CATCH);
629 BasicBlock *no_handler = function()->CreateBlock("no_handler");
630 SwitchInst *switchinst = builder()->CreateSwitch(
631 index, no_handler, num_options);
633 for (int i = 0; i < num_options; i++) {
634 switchinst->addCase(
635 LLVMValue::jint_constant(i),
636 handler_for_exception(i));
637 }
639 builder()->SetInsertPoint(no_handler);
640 }
642 BasicBlock* SharkTopLevelBlock::handler_for_exception(int index) {
643 SharkTopLevelBlock *successor = this->exception(index);
644 if (successor) {
645 successor->add_incoming(current_state());
646 return successor->entry_block();
647 }
648 else {
649 return make_trap(
650 exc_handler(index)->handler_bci(),
651 Deoptimization::make_trap_request(
652 Deoptimization::Reason_unhandled,
653 Deoptimization::Action_reinterpret));
654 }
655 }
657 void SharkTopLevelBlock::maybe_add_safepoint() {
658 if (current_state()->has_safepointed())
659 return;
661 BasicBlock *orig_block = builder()->GetInsertBlock();
662 SharkState *orig_state = current_state()->copy();
664 BasicBlock *do_safepoint = function()->CreateBlock("do_safepoint");
665 BasicBlock *safepointed = function()->CreateBlock("safepointed");
667 Value *state = builder()->CreateLoad(
668 builder()->CreateIntToPtr(
669 LLVMValue::intptr_constant(
670 (intptr_t) SafepointSynchronize::address_of_state()),
671 PointerType::getUnqual(SharkType::jint_type())),
672 "state");
674 builder()->CreateCondBr(
675 builder()->CreateICmpEQ(
676 state,
677 LLVMValue::jint_constant(SafepointSynchronize::_synchronizing)),
678 do_safepoint, safepointed);
680 builder()->SetInsertPoint(do_safepoint);
681 call_vm(builder()->safepoint(), EX_CHECK_FULL);
682 BasicBlock *safepointed_block = builder()->GetInsertBlock();
683 builder()->CreateBr(safepointed);
685 builder()->SetInsertPoint(safepointed);
686 current_state()->merge(orig_state, orig_block, safepointed_block);
688 current_state()->set_has_safepointed(true);
689 }
691 void SharkTopLevelBlock::maybe_add_backedge_safepoint() {
692 if (current_state()->has_safepointed())
693 return;
695 for (int i = 0; i < num_successors(); i++) {
696 if (successor(i)->can_reach(this)) {
697 maybe_add_safepoint();
698 break;
699 }
700 }
701 }
703 bool SharkTopLevelBlock::can_reach(SharkTopLevelBlock* other) {
704 for (int i = 0; i < function()->block_count(); i++)
705 function()->block(i)->_can_reach_visited = false;
707 return can_reach_helper(other);
708 }
710 bool SharkTopLevelBlock::can_reach_helper(SharkTopLevelBlock* other) {
711 if (this == other)
712 return true;
714 if (_can_reach_visited)
715 return false;
716 _can_reach_visited = true;
718 if (!has_trap()) {
719 for (int i = 0; i < num_successors(); i++) {
720 if (successor(i)->can_reach_helper(other))
721 return true;
722 }
723 }
725 for (int i = 0; i < num_exceptions(); i++) {
726 SharkTopLevelBlock *handler = exception(i);
727 if (handler && handler->can_reach_helper(other))
728 return true;
729 }
731 return false;
732 }
734 BasicBlock* SharkTopLevelBlock::make_trap(int trap_bci, int trap_request) {
735 BasicBlock *trap_block = function()->CreateBlock("trap");
736 BasicBlock *orig_block = builder()->GetInsertBlock();
737 builder()->SetInsertPoint(trap_block);
739 int orig_bci = bci();
740 iter()->force_bci(trap_bci);
742 do_trap(trap_request);
744 builder()->SetInsertPoint(orig_block);
745 iter()->force_bci(orig_bci);
747 return trap_block;
748 }
750 void SharkTopLevelBlock::do_trap(int trap_request) {
751 decache_for_trap();
752 builder()->CreateRet(
753 builder()->CreateCall2(
754 builder()->uncommon_trap(),
755 thread(),
756 LLVMValue::jint_constant(trap_request)));
757 }
759 void SharkTopLevelBlock::call_register_finalizer(Value *receiver) {
760 BasicBlock *orig_block = builder()->GetInsertBlock();
761 SharkState *orig_state = current_state()->copy();
763 BasicBlock *do_call = function()->CreateBlock("has_finalizer");
764 BasicBlock *done = function()->CreateBlock("done");
766 Value *klass = builder()->CreateValueOfStructEntry(
767 receiver,
768 in_ByteSize(oopDesc::klass_offset_in_bytes()),
769 SharkType::oop_type(),
770 "klass");
772 Value *access_flags = builder()->CreateValueOfStructEntry(
773 klass,
774 Klass::access_flags_offset(),
775 SharkType::jint_type(),
776 "access_flags");
778 builder()->CreateCondBr(
779 builder()->CreateICmpNE(
780 builder()->CreateAnd(
781 access_flags,
782 LLVMValue::jint_constant(JVM_ACC_HAS_FINALIZER)),
783 LLVMValue::jint_constant(0)),
784 do_call, done);
786 builder()->SetInsertPoint(do_call);
787 call_vm(builder()->register_finalizer(), receiver, EX_CHECK_FULL);
788 BasicBlock *branch_block = builder()->GetInsertBlock();
789 builder()->CreateBr(done);
791 builder()->SetInsertPoint(done);
792 current_state()->merge(orig_state, orig_block, branch_block);
793 }
795 void SharkTopLevelBlock::handle_return(BasicType type, Value* exception) {
796 assert (exception == NULL || type == T_VOID, "exception OR result, please");
798 if (num_monitors()) {
799 // Protect our exception across possible monitor release decaches
800 if (exception)
801 set_oop_tmp(exception);
803 // We don't need to check for exceptions thrown here. If
804 // we're returning a value then we just carry on as normal:
805 // the caller will see the pending exception and handle it.
806 // If we're returning with an exception then that exception
807 // takes priority and the release_lock one will be ignored.
808 while (num_monitors())
809 release_lock(EX_CHECK_NONE);
811 // Reload the exception we're throwing
812 if (exception)
813 exception = get_oop_tmp();
814 }
816 if (exception) {
817 builder()->CreateStore(exception, pending_exception_address());
818 }
820 Value *result_addr = stack()->CreatePopFrame(type2size[type]);
821 if (type != T_VOID) {
822 builder()->CreateStore(
823 pop_result(type)->generic_value(),
824 builder()->CreateIntToPtr(
825 result_addr,
826 PointerType::getUnqual(SharkType::to_stackType(type))));
827 }
829 builder()->CreateRet(LLVMValue::jint_constant(0));
830 }
832 void SharkTopLevelBlock::do_arraylength() {
833 SharkValue *array = pop();
834 check_null(array);
835 Value *length = builder()->CreateArrayLength(array->jarray_value());
836 push(SharkValue::create_jint(length, false));
837 }
839 void SharkTopLevelBlock::do_aload(BasicType basic_type) {
840 SharkValue *index = pop();
841 SharkValue *array = pop();
843 check_null(array);
844 check_bounds(array, index);
846 Value *value = builder()->CreateLoad(
847 builder()->CreateArrayAddress(
848 array->jarray_value(), basic_type, index->jint_value()));
850 Type *stack_type = SharkType::to_stackType(basic_type);
851 if (value->getType() != stack_type)
852 value = builder()->CreateIntCast(value, stack_type, basic_type != T_CHAR);
854 switch (basic_type) {
855 case T_BYTE:
856 case T_CHAR:
857 case T_SHORT:
858 case T_INT:
859 push(SharkValue::create_jint(value, false));
860 break;
862 case T_LONG:
863 push(SharkValue::create_jlong(value, false));
864 break;
866 case T_FLOAT:
867 push(SharkValue::create_jfloat(value));
868 break;
870 case T_DOUBLE:
871 push(SharkValue::create_jdouble(value));
872 break;
874 case T_OBJECT:
875 // You might expect that array->type()->is_array_klass() would
876 // always be true, but it isn't. If ciTypeFlow detects that a
877 // value is always null then that value becomes an untyped null
878 // object. Shark doesn't presently support this, so a generic
879 // T_OBJECT is created. In this case we guess the type using
880 // the BasicType we were supplied. In reality the generated
881 // code will never be used, as the null value will be caught
882 // by the above null pointer check.
883 // http://icedtea.classpath.org/bugzilla/show_bug.cgi?id=324
884 push(
885 SharkValue::create_generic(
886 array->type()->is_array_klass() ?
887 ((ciArrayKlass *) array->type())->element_type() :
888 ciType::make(basic_type),
889 value, false));
890 break;
892 default:
893 tty->print_cr("Unhandled type %s", type2name(basic_type));
894 ShouldNotReachHere();
895 }
896 }
898 void SharkTopLevelBlock::do_astore(BasicType basic_type) {
899 SharkValue *svalue = pop();
900 SharkValue *index = pop();
901 SharkValue *array = pop();
903 check_null(array);
904 check_bounds(array, index);
906 Value *value;
907 switch (basic_type) {
908 case T_BYTE:
909 case T_CHAR:
910 case T_SHORT:
911 case T_INT:
912 value = svalue->jint_value();
913 break;
915 case T_LONG:
916 value = svalue->jlong_value();
917 break;
919 case T_FLOAT:
920 value = svalue->jfloat_value();
921 break;
923 case T_DOUBLE:
924 value = svalue->jdouble_value();
925 break;
927 case T_OBJECT:
928 value = svalue->jobject_value();
929 // XXX assignability check
930 break;
932 default:
933 tty->print_cr("Unhandled type %s", type2name(basic_type));
934 ShouldNotReachHere();
935 }
937 Type *array_type = SharkType::to_arrayType(basic_type);
938 if (value->getType() != array_type)
939 value = builder()->CreateIntCast(value, array_type, basic_type != T_CHAR);
941 Value *addr = builder()->CreateArrayAddress(
942 array->jarray_value(), basic_type, index->jint_value(), "addr");
944 builder()->CreateStore(value, addr);
946 if (basic_type == T_OBJECT) // XXX or T_ARRAY?
947 builder()->CreateUpdateBarrierSet(oopDesc::bs(), addr);
948 }
950 void SharkTopLevelBlock::do_return(BasicType type) {
951 if (target()->intrinsic_id() == vmIntrinsics::_Object_init)
952 call_register_finalizer(local(0)->jobject_value());
953 maybe_add_safepoint();
954 handle_return(type, NULL);
955 }
957 void SharkTopLevelBlock::do_athrow() {
958 SharkValue *exception = pop();
959 check_null(exception);
960 handle_exception(exception->jobject_value(), EX_CHECK_FULL);
961 }
963 void SharkTopLevelBlock::do_goto() {
964 do_branch(ciTypeFlow::GOTO_TARGET);
965 }
967 void SharkTopLevelBlock::do_jsr() {
968 push(SharkValue::address_constant(iter()->next_bci()));
969 do_branch(ciTypeFlow::GOTO_TARGET);
970 }
972 void SharkTopLevelBlock::do_ret() {
973 assert(local(iter()->get_index())->address_value() ==
974 successor(ciTypeFlow::GOTO_TARGET)->start(), "should be");
975 do_branch(ciTypeFlow::GOTO_TARGET);
976 }
978 // All propagation of state from one block to the next (via
979 // dest->add_incoming) is handled by these methods:
980 // do_branch
981 // do_if_helper
982 // do_switch
983 // handle_exception
985 void SharkTopLevelBlock::do_branch(int successor_index) {
986 SharkTopLevelBlock *dest = successor(successor_index);
987 builder()->CreateBr(dest->entry_block());
988 dest->add_incoming(current_state());
989 }
991 void SharkTopLevelBlock::do_if(ICmpInst::Predicate p,
992 SharkValue* b,
993 SharkValue* a) {
994 Value *llvm_a, *llvm_b;
995 if (a->is_jobject()) {
996 llvm_a = a->intptr_value(builder());
997 llvm_b = b->intptr_value(builder());
998 }
999 else {
1000 llvm_a = a->jint_value();
1001 llvm_b = b->jint_value();
1002 }
1003 do_if_helper(p, llvm_b, llvm_a, current_state(), current_state());
1004 }
1006 void SharkTopLevelBlock::do_if_helper(ICmpInst::Predicate p,
1007 Value* b,
1008 Value* a,
1009 SharkState* if_taken_state,
1010 SharkState* not_taken_state) {
1011 SharkTopLevelBlock *if_taken = successor(ciTypeFlow::IF_TAKEN);
1012 SharkTopLevelBlock *not_taken = successor(ciTypeFlow::IF_NOT_TAKEN);
1014 builder()->CreateCondBr(
1015 builder()->CreateICmp(p, a, b),
1016 if_taken->entry_block(), not_taken->entry_block());
1018 if_taken->add_incoming(if_taken_state);
1019 not_taken->add_incoming(not_taken_state);
1020 }
1022 void SharkTopLevelBlock::do_switch() {
1023 int len = switch_table_length();
1025 SharkTopLevelBlock *dest_block = successor(ciTypeFlow::SWITCH_DEFAULT);
1026 SwitchInst *switchinst = builder()->CreateSwitch(
1027 pop()->jint_value(), dest_block->entry_block(), len);
1028 dest_block->add_incoming(current_state());
1030 for (int i = 0; i < len; i++) {
1031 int dest_bci = switch_dest(i);
1032 if (dest_bci != switch_default_dest()) {
1033 dest_block = bci_successor(dest_bci);
1034 switchinst->addCase(
1035 LLVMValue::jint_constant(switch_key(i)),
1036 dest_block->entry_block());
1037 dest_block->add_incoming(current_state());
1038 }
1039 }
1040 }
1042 ciMethod* SharkTopLevelBlock::improve_virtual_call(ciMethod* caller,
1043 ciInstanceKlass* klass,
1044 ciMethod* dest_method,
1045 ciType* receiver_type) {
1046 // If the method is obviously final then we are already done
1047 if (dest_method->can_be_statically_bound())
1048 return dest_method;
1050 // Array methods are all inherited from Object and are monomorphic
1051 if (receiver_type->is_array_klass() &&
1052 dest_method->holder() == java_lang_Object_klass())
1053 return dest_method;
1055 // This code can replace a virtual call with a direct call if this
1056 // class is the only one in the entire set of loaded classes that
1057 // implements this method. This makes the compiled code dependent
1058 // on other classes that implement the method not being loaded, a
1059 // condition which is enforced by the dependency tracker. If the
1060 // dependency tracker determines a method has become invalid it
1061 // will mark it for recompilation, causing running copies to be
1062 // deoptimized. Shark currently can't deoptimize arbitrarily like
1063 // that, so this optimization cannot be used.
1064 // http://icedtea.classpath.org/bugzilla/show_bug.cgi?id=481
1066 // All other interesting cases are instance classes
1067 if (!receiver_type->is_instance_klass())
1068 return NULL;
1070 // Attempt to improve the receiver
1071 ciInstanceKlass* actual_receiver = klass;
1072 ciInstanceKlass *improved_receiver = receiver_type->as_instance_klass();
1073 if (improved_receiver->is_loaded() &&
1074 improved_receiver->is_initialized() &&
1075 !improved_receiver->is_interface() &&
1076 improved_receiver->is_subtype_of(actual_receiver)) {
1077 actual_receiver = improved_receiver;
1078 }
1080 // Attempt to find a monomorphic target for this call using
1081 // class heirachy analysis.
1082 ciInstanceKlass *calling_klass = caller->holder();
1083 ciMethod* monomorphic_target =
1084 dest_method->find_monomorphic_target(calling_klass, klass, actual_receiver);
1085 if (monomorphic_target != NULL) {
1086 assert(!monomorphic_target->is_abstract(), "shouldn't be");
1088 function()->dependencies()->assert_unique_concrete_method(actual_receiver, monomorphic_target);
1090 // Opto has a bunch of type checking here that I don't
1091 // understand. It's to inhibit casting in one direction,
1092 // possibly because objects in Opto can have inexact
1093 // types, but I can't even tell which direction it
1094 // doesn't like. For now I'm going to block *any* cast.
1095 if (monomorphic_target != dest_method) {
1096 if (SharkPerformanceWarnings) {
1097 warning("found monomorphic target, but inhibited cast:");
1098 tty->print(" dest_method = ");
1099 dest_method->print_short_name(tty);
1100 tty->cr();
1101 tty->print(" monomorphic_target = ");
1102 monomorphic_target->print_short_name(tty);
1103 tty->cr();
1104 }
1105 monomorphic_target = NULL;
1106 }
1107 }
1109 // Replace the virtual call with a direct one. This makes
1110 // us dependent on that target method not getting overridden
1111 // by dynamic class loading.
1112 if (monomorphic_target != NULL) {
1113 dependencies()->assert_unique_concrete_method(
1114 actual_receiver, monomorphic_target);
1115 return monomorphic_target;
1116 }
1118 // Because Opto distinguishes exact types from inexact ones
1119 // it can perform a further optimization to replace calls
1120 // with non-monomorphic targets if the receiver has an exact
1121 // type. We don't mark types this way, so we can't do this.
1124 return NULL;
1125 }
1127 Value *SharkTopLevelBlock::get_direct_callee(ciMethod* method) {
1128 return builder()->CreateBitCast(
1129 builder()->CreateInlineMetadata(method, SharkType::Method_type()),
1130 SharkType::Method_type(),
1131 "callee");
1132 }
1134 Value *SharkTopLevelBlock::get_virtual_callee(SharkValue* receiver,
1135 int vtable_index) {
1136 Value *klass = builder()->CreateValueOfStructEntry(
1137 receiver->jobject_value(),
1138 in_ByteSize(oopDesc::klass_offset_in_bytes()),
1139 SharkType::oop_type(),
1140 "klass");
1142 return builder()->CreateLoad(
1143 builder()->CreateArrayAddress(
1144 klass,
1145 SharkType::Method_type(),
1146 vtableEntry::size() * wordSize,
1147 in_ByteSize(InstanceKlass::vtable_start_offset() * wordSize),
1148 LLVMValue::intptr_constant(vtable_index)),
1149 "callee");
1150 }
1152 Value* SharkTopLevelBlock::get_interface_callee(SharkValue *receiver,
1153 ciMethod* method) {
1154 BasicBlock *loop = function()->CreateBlock("loop");
1155 BasicBlock *got_null = function()->CreateBlock("got_null");
1156 BasicBlock *not_null = function()->CreateBlock("not_null");
1157 BasicBlock *next = function()->CreateBlock("next");
1158 BasicBlock *got_entry = function()->CreateBlock("got_entry");
1160 // Locate the receiver's itable
1161 Value *object_klass = builder()->CreateValueOfStructEntry(
1162 receiver->jobject_value(), in_ByteSize(oopDesc::klass_offset_in_bytes()),
1163 SharkType::klass_type(),
1164 "object_klass");
1166 Value *vtable_start = builder()->CreateAdd(
1167 builder()->CreatePtrToInt(object_klass, SharkType::intptr_type()),
1168 LLVMValue::intptr_constant(
1169 InstanceKlass::vtable_start_offset() * HeapWordSize),
1170 "vtable_start");
1172 Value *vtable_length = builder()->CreateValueOfStructEntry(
1173 object_klass,
1174 in_ByteSize(InstanceKlass::vtable_length_offset() * HeapWordSize),
1175 SharkType::jint_type(),
1176 "vtable_length");
1177 vtable_length =
1178 builder()->CreateIntCast(vtable_length, SharkType::intptr_type(), false);
1180 bool needs_aligning = HeapWordsPerLong > 1;
1181 Value *itable_start = builder()->CreateAdd(
1182 vtable_start,
1183 builder()->CreateShl(
1184 vtable_length,
1185 LLVMValue::intptr_constant(exact_log2(vtableEntry::size() * wordSize))),
1186 needs_aligning ? "" : "itable_start");
1187 if (needs_aligning) {
1188 itable_start = builder()->CreateAnd(
1189 builder()->CreateAdd(
1190 itable_start, LLVMValue::intptr_constant(BytesPerLong - 1)),
1191 LLVMValue::intptr_constant(~(BytesPerLong - 1)),
1192 "itable_start");
1193 }
1195 // Locate this interface's entry in the table
1196 Value *iklass = builder()->CreateInlineMetadata(method->holder(), SharkType::klass_type());
1197 BasicBlock *loop_entry = builder()->GetInsertBlock();
1198 builder()->CreateBr(loop);
1199 builder()->SetInsertPoint(loop);
1200 PHINode *itable_entry_addr = builder()->CreatePHI(
1201 SharkType::intptr_type(), 0, "itable_entry_addr");
1202 itable_entry_addr->addIncoming(itable_start, loop_entry);
1204 Value *itable_entry = builder()->CreateIntToPtr(
1205 itable_entry_addr, SharkType::itableOffsetEntry_type(), "itable_entry");
1207 Value *itable_iklass = builder()->CreateValueOfStructEntry(
1208 itable_entry,
1209 in_ByteSize(itableOffsetEntry::interface_offset_in_bytes()),
1210 SharkType::klass_type(),
1211 "itable_iklass");
1213 builder()->CreateCondBr(
1214 builder()->CreateICmpEQ(itable_iklass, LLVMValue::nullKlass()),
1215 got_null, not_null);
1217 // A null entry means that the class doesn't implement the
1218 // interface, and wasn't the same as the class checked when
1219 // the interface was resolved.
1220 builder()->SetInsertPoint(got_null);
1221 builder()->CreateUnimplemented(__FILE__, __LINE__);
1222 builder()->CreateUnreachable();
1224 builder()->SetInsertPoint(not_null);
1225 builder()->CreateCondBr(
1226 builder()->CreateICmpEQ(itable_iklass, iklass),
1227 got_entry, next);
1229 builder()->SetInsertPoint(next);
1230 Value *next_entry = builder()->CreateAdd(
1231 itable_entry_addr,
1232 LLVMValue::intptr_constant(itableOffsetEntry::size() * wordSize));
1233 builder()->CreateBr(loop);
1234 itable_entry_addr->addIncoming(next_entry, next);
1236 // Locate the method pointer
1237 builder()->SetInsertPoint(got_entry);
1238 Value *offset = builder()->CreateValueOfStructEntry(
1239 itable_entry,
1240 in_ByteSize(itableOffsetEntry::offset_offset_in_bytes()),
1241 SharkType::jint_type(),
1242 "offset");
1243 offset =
1244 builder()->CreateIntCast(offset, SharkType::intptr_type(), false);
1246 return builder()->CreateLoad(
1247 builder()->CreateIntToPtr(
1248 builder()->CreateAdd(
1249 builder()->CreateAdd(
1250 builder()->CreateAdd(
1251 builder()->CreatePtrToInt(
1252 object_klass, SharkType::intptr_type()),
1253 offset),
1254 LLVMValue::intptr_constant(
1255 method->itable_index() * itableMethodEntry::size() * wordSize)),
1256 LLVMValue::intptr_constant(
1257 itableMethodEntry::method_offset_in_bytes())),
1258 PointerType::getUnqual(SharkType::Method_type())),
1259 "callee");
1260 }
1262 void SharkTopLevelBlock::do_call() {
1263 // Set frequently used booleans
1264 bool is_static = bc() == Bytecodes::_invokestatic;
1265 bool is_virtual = bc() == Bytecodes::_invokevirtual;
1266 bool is_interface = bc() == Bytecodes::_invokeinterface;
1268 // Find the method being called
1269 bool will_link;
1270 ciSignature* sig;
1271 ciMethod *dest_method = iter()->get_method(will_link, &sig);
1273 assert(will_link, "typeflow responsibility");
1274 assert(dest_method->is_static() == is_static, "must match bc");
1276 // Find the class of the method being called. Note
1277 // that the superclass check in the second assertion
1278 // is to cope with a hole in the spec that allows for
1279 // invokeinterface instructions where the resolved
1280 // method is a virtual method in java.lang.Object.
1281 // javac doesn't generate code like that, but there's
1282 // no reason a compliant Java compiler might not.
1283 ciInstanceKlass *holder_klass = dest_method->holder();
1284 assert(holder_klass->is_loaded(), "scan_for_traps responsibility");
1285 assert(holder_klass->is_interface() ||
1286 holder_klass->super() == NULL ||
1287 !is_interface, "must match bc");
1289 bool is_forced_virtual = is_interface && holder_klass == java_lang_Object_klass();
1291 ciKlass *holder = iter()->get_declared_method_holder();
1292 ciInstanceKlass *klass =
1293 ciEnv::get_instance_klass_for_declared_method_holder(holder);
1295 if (is_forced_virtual) {
1296 klass = java_lang_Object_klass();
1297 }
1299 // Find the receiver in the stack. We do this before
1300 // trying to inline because the inliner can only use
1301 // zero-checked values, not being able to perform the
1302 // check itself.
1303 SharkValue *receiver = NULL;
1304 if (!is_static) {
1305 receiver = xstack(dest_method->arg_size() - 1);
1306 check_null(receiver);
1307 }
1309 // Try to improve non-direct calls
1310 bool call_is_virtual = is_virtual || is_interface;
1311 ciMethod *call_method = dest_method;
1312 if (call_is_virtual) {
1313 ciMethod *optimized_method = improve_virtual_call(
1314 target(), klass, dest_method, receiver->type());
1315 if (optimized_method) {
1316 call_method = optimized_method;
1317 call_is_virtual = false;
1318 }
1319 }
1321 // Try to inline the call
1322 if (!call_is_virtual) {
1323 if (SharkInliner::attempt_inline(call_method, current_state())) {
1324 return;
1325 }
1326 }
1328 // Find the method we are calling
1329 Value *callee;
1330 if (call_is_virtual) {
1331 if (is_virtual || is_forced_virtual) {
1332 assert(klass->is_linked(), "scan_for_traps responsibility");
1333 int vtable_index = call_method->resolve_vtable_index(
1334 target()->holder(), klass);
1335 assert(vtable_index >= 0, "should be");
1336 callee = get_virtual_callee(receiver, vtable_index);
1337 }
1338 else {
1339 assert(is_interface, "should be");
1340 callee = get_interface_callee(receiver, call_method);
1341 }
1342 }
1343 else {
1344 callee = get_direct_callee(call_method);
1345 }
1347 // Load the SharkEntry from the callee
1348 Value *base_pc = builder()->CreateValueOfStructEntry(
1349 callee, Method::from_interpreted_offset(),
1350 SharkType::intptr_type(),
1351 "base_pc");
1353 // Load the entry point from the SharkEntry
1354 Value *entry_point = builder()->CreateLoad(
1355 builder()->CreateIntToPtr(
1356 builder()->CreateAdd(
1357 base_pc,
1358 LLVMValue::intptr_constant(in_bytes(ZeroEntry::entry_point_offset()))),
1359 PointerType::getUnqual(
1360 PointerType::getUnqual(SharkType::entry_point_type()))),
1361 "entry_point");
1363 // Make the call
1364 decache_for_Java_call(call_method);
1365 Value *deoptimized_frames = builder()->CreateCall3(
1366 entry_point, callee, base_pc, thread());
1368 // If the callee got deoptimized then reexecute in the interpreter
1369 BasicBlock *reexecute = function()->CreateBlock("reexecute");
1370 BasicBlock *call_completed = function()->CreateBlock("call_completed");
1371 builder()->CreateCondBr(
1372 builder()->CreateICmpNE(deoptimized_frames, LLVMValue::jint_constant(0)),
1373 reexecute, call_completed);
1375 builder()->SetInsertPoint(reexecute);
1376 builder()->CreateCall2(
1377 builder()->deoptimized_entry_point(),
1378 builder()->CreateSub(deoptimized_frames, LLVMValue::jint_constant(1)),
1379 thread());
1380 builder()->CreateBr(call_completed);
1382 // Cache after the call
1383 builder()->SetInsertPoint(call_completed);
1384 cache_after_Java_call(call_method);
1386 // Check for pending exceptions
1387 check_pending_exception(EX_CHECK_FULL);
1389 // Mark that a safepoint check has occurred
1390 current_state()->set_has_safepointed(true);
1391 }
1393 bool SharkTopLevelBlock::static_subtype_check(ciKlass* check_klass,
1394 ciKlass* object_klass) {
1395 // If the class we're checking against is java.lang.Object
1396 // then this is a no brainer. Apparently this can happen
1397 // in reflective code...
1398 if (check_klass == java_lang_Object_klass())
1399 return true;
1401 // Perform a subtype check. NB in opto's code for this
1402 // (GraphKit::static_subtype_check) it says that static
1403 // interface types cannot be trusted, and if opto can't
1404 // trust them then I assume we can't either.
1405 if (object_klass->is_loaded() && !object_klass->is_interface()) {
1406 if (object_klass == check_klass)
1407 return true;
1409 if (check_klass->is_loaded() && object_klass->is_subtype_of(check_klass))
1410 return true;
1411 }
1413 return false;
1414 }
1416 void SharkTopLevelBlock::do_instance_check() {
1417 // Get the class we're checking against
1418 bool will_link;
1419 ciKlass *check_klass = iter()->get_klass(will_link);
1421 // Get the class of the object we're checking
1422 ciKlass *object_klass = xstack(0)->type()->as_klass();
1424 // Can we optimize this check away?
1425 if (static_subtype_check(check_klass, object_klass)) {
1426 if (bc() == Bytecodes::_instanceof) {
1427 pop();
1428 push(SharkValue::jint_constant(1));
1429 }
1430 return;
1431 }
1433 // Need to check this one at runtime
1434 if (will_link)
1435 do_full_instance_check(check_klass);
1436 else
1437 do_trapping_instance_check(check_klass);
1438 }
1440 bool SharkTopLevelBlock::maybe_do_instanceof_if() {
1441 // Get the class we're checking against
1442 bool will_link;
1443 ciKlass *check_klass = iter()->get_klass(will_link);
1445 // If the class is unloaded then the instanceof
1446 // cannot possibly succeed.
1447 if (!will_link)
1448 return false;
1450 // Keep a copy of the object we're checking
1451 SharkValue *old_object = xstack(0);
1453 // Get the class of the object we're checking
1454 ciKlass *object_klass = old_object->type()->as_klass();
1456 // If the instanceof can be optimized away at compile time
1457 // then any subsequent checkcasts will be too so we handle
1458 // it normally.
1459 if (static_subtype_check(check_klass, object_klass))
1460 return false;
1462 // Perform the instance check
1463 do_full_instance_check(check_klass);
1464 Value *result = pop()->jint_value();
1466 // Create the casted object
1467 SharkValue *new_object = SharkValue::create_generic(
1468 check_klass, old_object->jobject_value(), old_object->zero_checked());
1470 // Create two copies of the current state, one with the
1471 // original object and one with all instances of the
1472 // original object replaced with the new, casted object.
1473 SharkState *new_state = current_state();
1474 SharkState *old_state = new_state->copy();
1475 new_state->replace_all(old_object, new_object);
1477 // Perform the check-and-branch
1478 switch (iter()->next_bc()) {
1479 case Bytecodes::_ifeq:
1480 // branch if not an instance
1481 do_if_helper(
1482 ICmpInst::ICMP_EQ,
1483 LLVMValue::jint_constant(0), result,
1484 old_state, new_state);
1485 break;
1487 case Bytecodes::_ifne:
1488 // branch if an instance
1489 do_if_helper(
1490 ICmpInst::ICMP_NE,
1491 LLVMValue::jint_constant(0), result,
1492 new_state, old_state);
1493 break;
1495 default:
1496 ShouldNotReachHere();
1497 }
1499 return true;
1500 }
1502 void SharkTopLevelBlock::do_full_instance_check(ciKlass* klass) {
1503 BasicBlock *not_null = function()->CreateBlock("not_null");
1504 BasicBlock *subtype_check = function()->CreateBlock("subtype_check");
1505 BasicBlock *is_instance = function()->CreateBlock("is_instance");
1506 BasicBlock *not_instance = function()->CreateBlock("not_instance");
1507 BasicBlock *merge1 = function()->CreateBlock("merge1");
1508 BasicBlock *merge2 = function()->CreateBlock("merge2");
1510 enum InstanceCheckStates {
1511 IC_IS_NULL,
1512 IC_IS_INSTANCE,
1513 IC_NOT_INSTANCE,
1514 };
1516 // Pop the object off the stack
1517 Value *object = pop()->jobject_value();
1519 // Null objects aren't instances of anything
1520 builder()->CreateCondBr(
1521 builder()->CreateICmpEQ(object, LLVMValue::null()),
1522 merge2, not_null);
1523 BasicBlock *null_block = builder()->GetInsertBlock();
1525 // Get the class we're checking against
1526 builder()->SetInsertPoint(not_null);
1527 Value *check_klass = builder()->CreateInlineMetadata(klass, SharkType::klass_type());
1529 // Get the class of the object being tested
1530 Value *object_klass = builder()->CreateValueOfStructEntry(
1531 object, in_ByteSize(oopDesc::klass_offset_in_bytes()),
1532 SharkType::klass_type(),
1533 "object_klass");
1535 // Perform the check
1536 builder()->CreateCondBr(
1537 builder()->CreateICmpEQ(check_klass, object_klass),
1538 is_instance, subtype_check);
1540 builder()->SetInsertPoint(subtype_check);
1541 builder()->CreateCondBr(
1542 builder()->CreateICmpNE(
1543 builder()->CreateCall2(
1544 builder()->is_subtype_of(), check_klass, object_klass),
1545 LLVMValue::jbyte_constant(0)),
1546 is_instance, not_instance);
1548 builder()->SetInsertPoint(is_instance);
1549 builder()->CreateBr(merge1);
1551 builder()->SetInsertPoint(not_instance);
1552 builder()->CreateBr(merge1);
1554 // First merge
1555 builder()->SetInsertPoint(merge1);
1556 PHINode *nonnull_result = builder()->CreatePHI(
1557 SharkType::jint_type(), 0, "nonnull_result");
1558 nonnull_result->addIncoming(
1559 LLVMValue::jint_constant(IC_IS_INSTANCE), is_instance);
1560 nonnull_result->addIncoming(
1561 LLVMValue::jint_constant(IC_NOT_INSTANCE), not_instance);
1562 BasicBlock *nonnull_block = builder()->GetInsertBlock();
1563 builder()->CreateBr(merge2);
1565 // Second merge
1566 builder()->SetInsertPoint(merge2);
1567 PHINode *result = builder()->CreatePHI(
1568 SharkType::jint_type(), 0, "result");
1569 result->addIncoming(LLVMValue::jint_constant(IC_IS_NULL), null_block);
1570 result->addIncoming(nonnull_result, nonnull_block);
1572 // Handle the result
1573 if (bc() == Bytecodes::_checkcast) {
1574 BasicBlock *failure = function()->CreateBlock("failure");
1575 BasicBlock *success = function()->CreateBlock("success");
1577 builder()->CreateCondBr(
1578 builder()->CreateICmpNE(
1579 result, LLVMValue::jint_constant(IC_NOT_INSTANCE)),
1580 success, failure);
1582 builder()->SetInsertPoint(failure);
1583 SharkState *saved_state = current_state()->copy();
1585 call_vm(
1586 builder()->throw_ClassCastException(),
1587 builder()->CreateIntToPtr(
1588 LLVMValue::intptr_constant((intptr_t) __FILE__),
1589 PointerType::getUnqual(SharkType::jbyte_type())),
1590 LLVMValue::jint_constant(__LINE__),
1591 EX_CHECK_NONE);
1593 Value *pending_exception = get_pending_exception();
1594 clear_pending_exception();
1595 handle_exception(pending_exception, EX_CHECK_FULL);
1597 set_current_state(saved_state);
1598 builder()->SetInsertPoint(success);
1599 push(SharkValue::create_generic(klass, object, false));
1600 }
1601 else {
1602 push(
1603 SharkValue::create_jint(
1604 builder()->CreateIntCast(
1605 builder()->CreateICmpEQ(
1606 result, LLVMValue::jint_constant(IC_IS_INSTANCE)),
1607 SharkType::jint_type(), false), false));
1608 }
1609 }
1611 void SharkTopLevelBlock::do_trapping_instance_check(ciKlass* klass) {
1612 BasicBlock *not_null = function()->CreateBlock("not_null");
1613 BasicBlock *is_null = function()->CreateBlock("null");
1615 // Leave the object on the stack so it's there if we trap
1616 builder()->CreateCondBr(
1617 builder()->CreateICmpEQ(xstack(0)->jobject_value(), LLVMValue::null()),
1618 is_null, not_null);
1619 SharkState *saved_state = current_state()->copy();
1621 // If it's not null then we need to trap
1622 builder()->SetInsertPoint(not_null);
1623 set_current_state(saved_state->copy());
1624 do_trap(
1625 Deoptimization::make_trap_request(
1626 Deoptimization::Reason_uninitialized,
1627 Deoptimization::Action_reinterpret));
1629 // If it's null then we're ok
1630 builder()->SetInsertPoint(is_null);
1631 set_current_state(saved_state);
1632 if (bc() == Bytecodes::_checkcast) {
1633 push(SharkValue::create_generic(klass, pop()->jobject_value(), false));
1634 }
1635 else {
1636 pop();
1637 push(SharkValue::jint_constant(0));
1638 }
1639 }
1641 void SharkTopLevelBlock::do_new() {
1642 bool will_link;
1643 ciInstanceKlass* klass = iter()->get_klass(will_link)->as_instance_klass();
1644 assert(will_link, "typeflow responsibility");
1646 BasicBlock *got_tlab = NULL;
1647 BasicBlock *heap_alloc = NULL;
1648 BasicBlock *retry = NULL;
1649 BasicBlock *got_heap = NULL;
1650 BasicBlock *initialize = NULL;
1651 BasicBlock *got_fast = NULL;
1652 BasicBlock *slow_alloc_and_init = NULL;
1653 BasicBlock *got_slow = NULL;
1654 BasicBlock *push_object = NULL;
1656 SharkState *fast_state = NULL;
1658 Value *tlab_object = NULL;
1659 Value *heap_object = NULL;
1660 Value *fast_object = NULL;
1661 Value *slow_object = NULL;
1662 Value *object = NULL;
1664 // The fast path
1665 if (!Klass::layout_helper_needs_slow_path(klass->layout_helper())) {
1666 if (UseTLAB) {
1667 got_tlab = function()->CreateBlock("got_tlab");
1668 heap_alloc = function()->CreateBlock("heap_alloc");
1669 }
1670 retry = function()->CreateBlock("retry");
1671 got_heap = function()->CreateBlock("got_heap");
1672 initialize = function()->CreateBlock("initialize");
1673 slow_alloc_and_init = function()->CreateBlock("slow_alloc_and_init");
1674 push_object = function()->CreateBlock("push_object");
1676 size_t size_in_bytes = klass->size_helper() << LogHeapWordSize;
1678 // Thread local allocation
1679 if (UseTLAB) {
1680 Value *top_addr = builder()->CreateAddressOfStructEntry(
1681 thread(), Thread::tlab_top_offset(),
1682 PointerType::getUnqual(SharkType::intptr_type()),
1683 "top_addr");
1685 Value *end = builder()->CreateValueOfStructEntry(
1686 thread(), Thread::tlab_end_offset(),
1687 SharkType::intptr_type(),
1688 "end");
1690 Value *old_top = builder()->CreateLoad(top_addr, "old_top");
1691 Value *new_top = builder()->CreateAdd(
1692 old_top, LLVMValue::intptr_constant(size_in_bytes));
1694 builder()->CreateCondBr(
1695 builder()->CreateICmpULE(new_top, end),
1696 got_tlab, heap_alloc);
1698 builder()->SetInsertPoint(got_tlab);
1699 tlab_object = builder()->CreateIntToPtr(
1700 old_top, SharkType::oop_type(), "tlab_object");
1702 builder()->CreateStore(new_top, top_addr);
1703 builder()->CreateBr(initialize);
1705 builder()->SetInsertPoint(heap_alloc);
1706 }
1708 // Heap allocation
1709 Value *top_addr = builder()->CreateIntToPtr(
1710 LLVMValue::intptr_constant((intptr_t) Universe::heap()->top_addr()),
1711 PointerType::getUnqual(SharkType::intptr_type()),
1712 "top_addr");
1714 Value *end = builder()->CreateLoad(
1715 builder()->CreateIntToPtr(
1716 LLVMValue::intptr_constant((intptr_t) Universe::heap()->end_addr()),
1717 PointerType::getUnqual(SharkType::intptr_type())),
1718 "end");
1720 builder()->CreateBr(retry);
1721 builder()->SetInsertPoint(retry);
1723 Value *old_top = builder()->CreateLoad(top_addr, "top");
1724 Value *new_top = builder()->CreateAdd(
1725 old_top, LLVMValue::intptr_constant(size_in_bytes));
1727 builder()->CreateCondBr(
1728 builder()->CreateICmpULE(new_top, end),
1729 got_heap, slow_alloc_and_init);
1731 builder()->SetInsertPoint(got_heap);
1732 heap_object = builder()->CreateIntToPtr(
1733 old_top, SharkType::oop_type(), "heap_object");
1735 Value *check = builder()->CreateAtomicCmpXchg(top_addr, old_top, new_top, llvm::SequentiallyConsistent);
1736 builder()->CreateCondBr(
1737 builder()->CreateICmpEQ(old_top, check),
1738 initialize, retry);
1740 // Initialize the object
1741 builder()->SetInsertPoint(initialize);
1742 if (tlab_object) {
1743 PHINode *phi = builder()->CreatePHI(
1744 SharkType::oop_type(), 0, "fast_object");
1745 phi->addIncoming(tlab_object, got_tlab);
1746 phi->addIncoming(heap_object, got_heap);
1747 fast_object = phi;
1748 }
1749 else {
1750 fast_object = heap_object;
1751 }
1753 builder()->CreateMemset(
1754 builder()->CreateBitCast(
1755 fast_object, PointerType::getUnqual(SharkType::jbyte_type())),
1756 LLVMValue::jbyte_constant(0),
1757 LLVMValue::jint_constant(size_in_bytes),
1758 LLVMValue::jint_constant(HeapWordSize));
1760 Value *mark_addr = builder()->CreateAddressOfStructEntry(
1761 fast_object, in_ByteSize(oopDesc::mark_offset_in_bytes()),
1762 PointerType::getUnqual(SharkType::intptr_type()),
1763 "mark_addr");
1765 Value *klass_addr = builder()->CreateAddressOfStructEntry(
1766 fast_object, in_ByteSize(oopDesc::klass_offset_in_bytes()),
1767 PointerType::getUnqual(SharkType::klass_type()),
1768 "klass_addr");
1770 // Set the mark
1771 intptr_t mark;
1772 if (UseBiasedLocking) {
1773 Unimplemented();
1774 }
1775 else {
1776 mark = (intptr_t) markOopDesc::prototype();
1777 }
1778 builder()->CreateStore(LLVMValue::intptr_constant(mark), mark_addr);
1780 // Set the class
1781 Value *rtklass = builder()->CreateInlineMetadata(klass, SharkType::klass_type());
1782 builder()->CreateStore(rtklass, klass_addr);
1783 got_fast = builder()->GetInsertBlock();
1785 builder()->CreateBr(push_object);
1786 builder()->SetInsertPoint(slow_alloc_and_init);
1787 fast_state = current_state()->copy();
1788 }
1790 // The slow path
1791 call_vm(
1792 builder()->new_instance(),
1793 LLVMValue::jint_constant(iter()->get_klass_index()),
1794 EX_CHECK_FULL);
1795 slow_object = get_vm_result();
1796 got_slow = builder()->GetInsertBlock();
1798 // Push the object
1799 if (push_object) {
1800 builder()->CreateBr(push_object);
1801 builder()->SetInsertPoint(push_object);
1802 }
1803 if (fast_object) {
1804 PHINode *phi = builder()->CreatePHI(SharkType::oop_type(), 0, "object");
1805 phi->addIncoming(fast_object, got_fast);
1806 phi->addIncoming(slow_object, got_slow);
1807 object = phi;
1808 current_state()->merge(fast_state, got_fast, got_slow);
1809 }
1810 else {
1811 object = slow_object;
1812 }
1814 push(SharkValue::create_jobject(object, true));
1815 }
1817 void SharkTopLevelBlock::do_newarray() {
1818 BasicType type = (BasicType) iter()->get_index();
1820 call_vm(
1821 builder()->newarray(),
1822 LLVMValue::jint_constant(type),
1823 pop()->jint_value(),
1824 EX_CHECK_FULL);
1826 ciArrayKlass *array_klass = ciArrayKlass::make(ciType::make(type));
1827 push(SharkValue::create_generic(array_klass, get_vm_result(), true));
1828 }
1830 void SharkTopLevelBlock::do_anewarray() {
1831 bool will_link;
1832 ciKlass *klass = iter()->get_klass(will_link);
1833 assert(will_link, "typeflow responsibility");
1835 ciObjArrayKlass *array_klass = ciObjArrayKlass::make(klass);
1836 if (!array_klass->is_loaded()) {
1837 Unimplemented();
1838 }
1840 call_vm(
1841 builder()->anewarray(),
1842 LLVMValue::jint_constant(iter()->get_klass_index()),
1843 pop()->jint_value(),
1844 EX_CHECK_FULL);
1846 push(SharkValue::create_generic(array_klass, get_vm_result(), true));
1847 }
1849 void SharkTopLevelBlock::do_multianewarray() {
1850 bool will_link;
1851 ciArrayKlass *array_klass = iter()->get_klass(will_link)->as_array_klass();
1852 assert(will_link, "typeflow responsibility");
1854 // The dimensions are stack values, so we use their slots for the
1855 // dimensions array. Note that we are storing them in the reverse
1856 // of normal stack order.
1857 int ndims = iter()->get_dimensions();
1859 Value *dimensions = stack()->slot_addr(
1860 stack()->stack_slots_offset() + max_stack() - xstack_depth(),
1861 ArrayType::get(SharkType::jint_type(), ndims),
1862 "dimensions");
1864 for (int i = 0; i < ndims; i++) {
1865 builder()->CreateStore(
1866 xstack(ndims - 1 - i)->jint_value(),
1867 builder()->CreateStructGEP(dimensions, i));
1868 }
1870 call_vm(
1871 builder()->multianewarray(),
1872 LLVMValue::jint_constant(iter()->get_klass_index()),
1873 LLVMValue::jint_constant(ndims),
1874 builder()->CreateStructGEP(dimensions, 0),
1875 EX_CHECK_FULL);
1877 // Now we can pop the dimensions off the stack
1878 for (int i = 0; i < ndims; i++)
1879 pop();
1881 push(SharkValue::create_generic(array_klass, get_vm_result(), true));
1882 }
1884 void SharkTopLevelBlock::acquire_method_lock() {
1885 Value *lockee;
1886 if (target()->is_static()) {
1887 lockee = builder()->CreateInlineOop(target()->holder()->java_mirror());
1888 }
1889 else
1890 lockee = local(0)->jobject_value();
1892 iter()->force_bci(start()); // for the decache in acquire_lock
1893 acquire_lock(lockee, EX_CHECK_NO_CATCH);
1894 }
1896 void SharkTopLevelBlock::do_monitorenter() {
1897 SharkValue *lockee = pop();
1898 check_null(lockee);
1899 acquire_lock(lockee->jobject_value(), EX_CHECK_FULL);
1900 }
1902 void SharkTopLevelBlock::do_monitorexit() {
1903 pop(); // don't need this (monitors are block structured)
1904 release_lock(EX_CHECK_NO_CATCH);
1905 }
1907 void SharkTopLevelBlock::acquire_lock(Value *lockee, int exception_action) {
1908 BasicBlock *try_recursive = function()->CreateBlock("try_recursive");
1909 BasicBlock *got_recursive = function()->CreateBlock("got_recursive");
1910 BasicBlock *not_recursive = function()->CreateBlock("not_recursive");
1911 BasicBlock *acquired_fast = function()->CreateBlock("acquired_fast");
1912 BasicBlock *lock_acquired = function()->CreateBlock("lock_acquired");
1914 int monitor = num_monitors();
1915 Value *monitor_addr = stack()->monitor_addr(monitor);
1916 Value *monitor_object_addr = stack()->monitor_object_addr(monitor);
1917 Value *monitor_header_addr = stack()->monitor_header_addr(monitor);
1919 // Store the object and mark the slot as live
1920 builder()->CreateStore(lockee, monitor_object_addr);
1921 set_num_monitors(monitor + 1);
1923 // Try a simple lock
1924 Value *mark_addr = builder()->CreateAddressOfStructEntry(
1925 lockee, in_ByteSize(oopDesc::mark_offset_in_bytes()),
1926 PointerType::getUnqual(SharkType::intptr_type()),
1927 "mark_addr");
1929 Value *mark = builder()->CreateLoad(mark_addr, "mark");
1930 Value *disp = builder()->CreateOr(
1931 mark, LLVMValue::intptr_constant(markOopDesc::unlocked_value), "disp");
1932 builder()->CreateStore(disp, monitor_header_addr);
1934 Value *lock = builder()->CreatePtrToInt(
1935 monitor_header_addr, SharkType::intptr_type());
1936 Value *check = builder()->CreateAtomicCmpXchg(mark_addr, disp, lock, llvm::Acquire);
1937 builder()->CreateCondBr(
1938 builder()->CreateICmpEQ(disp, check),
1939 acquired_fast, try_recursive);
1941 // Locking failed, but maybe this thread already owns it
1942 builder()->SetInsertPoint(try_recursive);
1943 Value *addr = builder()->CreateAnd(
1944 disp,
1945 LLVMValue::intptr_constant(~markOopDesc::lock_mask_in_place));
1947 // NB we use the entire stack, but JavaThread::is_lock_owned()
1948 // uses a more limited range. I don't think it hurts though...
1949 Value *stack_limit = builder()->CreateValueOfStructEntry(
1950 thread(), Thread::stack_base_offset(),
1951 SharkType::intptr_type(),
1952 "stack_limit");
1954 assert(sizeof(size_t) == sizeof(intptr_t), "should be");
1955 Value *stack_size = builder()->CreateValueOfStructEntry(
1956 thread(), Thread::stack_size_offset(),
1957 SharkType::intptr_type(),
1958 "stack_size");
1960 Value *stack_start =
1961 builder()->CreateSub(stack_limit, stack_size, "stack_start");
1963 builder()->CreateCondBr(
1964 builder()->CreateAnd(
1965 builder()->CreateICmpUGE(addr, stack_start),
1966 builder()->CreateICmpULT(addr, stack_limit)),
1967 got_recursive, not_recursive);
1969 builder()->SetInsertPoint(got_recursive);
1970 builder()->CreateStore(LLVMValue::intptr_constant(0), monitor_header_addr);
1971 builder()->CreateBr(acquired_fast);
1973 // Create an edge for the state merge
1974 builder()->SetInsertPoint(acquired_fast);
1975 SharkState *fast_state = current_state()->copy();
1976 builder()->CreateBr(lock_acquired);
1978 // It's not a recursive case so we need to drop into the runtime
1979 builder()->SetInsertPoint(not_recursive);
1980 call_vm(
1981 builder()->monitorenter(), monitor_addr,
1982 exception_action | EAM_MONITOR_FUDGE);
1983 BasicBlock *acquired_slow = builder()->GetInsertBlock();
1984 builder()->CreateBr(lock_acquired);
1986 // All done
1987 builder()->SetInsertPoint(lock_acquired);
1988 current_state()->merge(fast_state, acquired_fast, acquired_slow);
1989 }
1991 void SharkTopLevelBlock::release_lock(int exception_action) {
1992 BasicBlock *not_recursive = function()->CreateBlock("not_recursive");
1993 BasicBlock *released_fast = function()->CreateBlock("released_fast");
1994 BasicBlock *slow_path = function()->CreateBlock("slow_path");
1995 BasicBlock *lock_released = function()->CreateBlock("lock_released");
1997 int monitor = num_monitors() - 1;
1998 Value *monitor_addr = stack()->monitor_addr(monitor);
1999 Value *monitor_object_addr = stack()->monitor_object_addr(monitor);
2000 Value *monitor_header_addr = stack()->monitor_header_addr(monitor);
2002 // If it is recursive then we're already done
2003 Value *disp = builder()->CreateLoad(monitor_header_addr);
2004 builder()->CreateCondBr(
2005 builder()->CreateICmpEQ(disp, LLVMValue::intptr_constant(0)),
2006 released_fast, not_recursive);
2008 // Try a simple unlock
2009 builder()->SetInsertPoint(not_recursive);
2011 Value *lock = builder()->CreatePtrToInt(
2012 monitor_header_addr, SharkType::intptr_type());
2014 Value *lockee = builder()->CreateLoad(monitor_object_addr);
2016 Value *mark_addr = builder()->CreateAddressOfStructEntry(
2017 lockee, in_ByteSize(oopDesc::mark_offset_in_bytes()),
2018 PointerType::getUnqual(SharkType::intptr_type()),
2019 "mark_addr");
2021 Value *check = builder()->CreateAtomicCmpXchg(mark_addr, lock, disp, llvm::Release);
2022 builder()->CreateCondBr(
2023 builder()->CreateICmpEQ(lock, check),
2024 released_fast, slow_path);
2026 // Create an edge for the state merge
2027 builder()->SetInsertPoint(released_fast);
2028 SharkState *fast_state = current_state()->copy();
2029 builder()->CreateBr(lock_released);
2031 // Need to drop into the runtime to release this one
2032 builder()->SetInsertPoint(slow_path);
2033 call_vm(builder()->monitorexit(), monitor_addr, exception_action);
2034 BasicBlock *released_slow = builder()->GetInsertBlock();
2035 builder()->CreateBr(lock_released);
2037 // All done
2038 builder()->SetInsertPoint(lock_released);
2039 current_state()->merge(fast_state, released_fast, released_slow);
2041 // The object slot is now dead
2042 set_num_monitors(monitor);
2043 }