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 */
25
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"
47
48 using namespace llvm;
49
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();
53
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();
58
59 ciField *field;
60 ciMethod *method;
61 ciInstanceKlass *klass;
62 bool will_link;
63 bool is_field;
64
65 switch (bc()) {
66 case Bytecodes::_ldc:
67 case Bytecodes::_ldc_w:
68 if (!SharkConstant::for_ldc(iter())->is_loaded()) {
69 set_trap(
70 Deoptimization::make_trap_request(
71 Deoptimization::Reason_uninitialized,
72 Deoptimization::Action_reinterpret), bci());
73 return;
74 }
75 break;
76
77 case Bytecodes::_getfield:
78 case Bytecodes::_getstatic:
79 case Bytecodes::_putfield:
80 case Bytecodes::_putstatic:
81 field = iter()->get_field(will_link);
82 assert(will_link, "typeflow responsibility");
83 is_field = (bc() == Bytecodes::_getfield || bc() == Bytecodes::_putfield);
84
85 // If the bytecode does not match the field then bail out to
86 // the interpreter to throw an IncompatibleClassChangeError
87 if (is_field == field->is_static()) {
88 set_trap(
89 Deoptimization::make_trap_request(
90 Deoptimization::Reason_unhandled,
91 Deoptimization::Action_none), bci());
92 return;
93 }
94
95 // Bail out if we are trying to access a static variable
96 // before the class initializer has completed.
97 if (!is_field && !field->holder()->is_initialized()) {
98 if (!static_field_ok_in_clinit(field)) {
99 set_trap(
100 Deoptimization::make_trap_request(
101 Deoptimization::Reason_uninitialized,
102 Deoptimization::Action_reinterpret), bci());
103 return;
104 }
105 }
106 break;
107
108 case Bytecodes::_invokestatic:
109 case Bytecodes::_invokespecial:
110 case Bytecodes::_invokevirtual:
111 case Bytecodes::_invokeinterface:
112 method = iter()->get_method(will_link);
113 assert(will_link, "typeflow responsibility");
114
115 if (!method->holder()->is_linked()) {
116 set_trap(
117 Deoptimization::make_trap_request(
118 Deoptimization::Reason_uninitialized,
119 Deoptimization::Action_reinterpret), bci());
120 return;
121 }
122
123 if (bc() == Bytecodes::_invokevirtual) {
124 klass = ciEnv::get_instance_klass_for_declared_method_holder(
125 iter()->get_declared_method_holder());
126 if (!klass->is_linked()) {
127 set_trap(
128 Deoptimization::make_trap_request(
129 Deoptimization::Reason_uninitialized,
130 Deoptimization::Action_reinterpret), bci());
131 return;
132 }
133 }
134 break;
135
136 case Bytecodes::_new:
137 klass = iter()->get_klass(will_link)->as_instance_klass();
138 assert(will_link, "typeflow responsibility");
139
140 // Bail out if the class is unloaded
141 if (iter()->is_unresolved_klass() || !klass->is_initialized()) {
142 set_trap(
143 Deoptimization::make_trap_request(
144 Deoptimization::Reason_uninitialized,
145 Deoptimization::Action_reinterpret), bci());
146 return;
147 }
148
149 // Bail out if the class cannot be instantiated
150 if (klass->is_abstract() || klass->is_interface() ||
151 klass->name() == ciSymbol::java_lang_Class()) {
152 set_trap(
153 Deoptimization::make_trap_request(
154 Deoptimization::Reason_unhandled,
155 Deoptimization::Action_reinterpret), bci());
156 return;
157 }
158 break;
159 }
160 }
161
162 // Trap if typeflow trapped (and we didn't before)
163 if (ciblock()->has_trap()) {
164 set_trap(
165 Deoptimization::make_trap_request(
166 Deoptimization::Reason_unloaded,
167 Deoptimization::Action_reinterpret,
168 ciblock()->trap_index()), ciblock()->trap_bci());
169 return;
170 }
171 }
172
173 bool SharkTopLevelBlock::static_field_ok_in_clinit(ciField* field) {
174 assert(field->is_static(), "should be");
175
176 // This code is lifted pretty much verbatim from C2's
177 // Parse::static_field_ok_in_clinit() in parse3.cpp.
178 bool access_OK = false;
179 if (target()->holder()->is_subclass_of(field->holder())) {
180 if (target()->is_static()) {
181 if (target()->name() == ciSymbol::class_initializer_name()) {
182 // It's OK to access static fields from the class initializer
183 access_OK = true;
184 }
185 }
186 else {
187 if (target()->name() == ciSymbol::object_initializer_name()) {
188 // It's also OK to access static fields inside a constructor,
189 // because any thread calling the constructor must first have
190 // synchronized on the class by executing a "new" bytecode.
191 access_OK = true;
192 }
193 }
194 }
195 return access_OK;
196 }
197
198 SharkState* SharkTopLevelBlock::entry_state() {
199 if (_entry_state == NULL) {
200 assert(needs_phis(), "should do");
201 _entry_state = new SharkPHIState(this);
202 }
203 return _entry_state;
204 }
205
206 void SharkTopLevelBlock::add_incoming(SharkState* incoming_state) {
207 if (needs_phis()) {
208 ((SharkPHIState *) entry_state())->add_incoming(incoming_state);
209 }
210 else if (_entry_state == NULL) {
211 _entry_state = incoming_state;
212 }
213 else {
214 assert(entry_state()->equal_to(incoming_state), "should be");
215 }
216 }
217
218 void SharkTopLevelBlock::enter(SharkTopLevelBlock* predecessor,
219 bool is_exception) {
220 // This block requires phis:
221 // - if it is entered more than once
222 // - if it is an exception handler, because in which
223 // case we assume it's entered more than once.
224 // - if the predecessor will be compiled after this
225 // block, in which case we can't simple propagate
226 // the state forward.
227 if (!needs_phis() &&
228 (entered() ||
229 is_exception ||
230 (predecessor && predecessor->index() >= index())))
231 _needs_phis = true;
232
233 // Recurse into the tree
234 if (!entered()) {
235 _entered = true;
236
237 scan_for_traps();
238 if (!has_trap()) {
239 for (int i = 0; i < num_successors(); i++) {
240 successor(i)->enter(this, false);
241 }
242 }
243 compute_exceptions();
244 for (int i = 0; i < num_exceptions(); i++) {
245 SharkTopLevelBlock *handler = exception(i);
246 if (handler)
247 handler->enter(this, true);
248 }
249 }
250 }
251
252 void SharkTopLevelBlock::initialize() {
253 char name[28];
254 snprintf(name, sizeof(name),
255 "bci_%d%s",
256 start(), is_backedge_copy() ? "_backedge_copy" : "");
257 _entry_block = function()->CreateBlock(name);
258 }
259
260 void SharkTopLevelBlock::decache_for_Java_call(ciMethod *callee) {
261 SharkJavaCallDecacher(function(), bci(), callee).scan(current_state());
262 for (int i = 0; i < callee->arg_size(); i++)
263 xpop();
264 }
265
266 void SharkTopLevelBlock::cache_after_Java_call(ciMethod *callee) {
267 if (callee->return_type()->size()) {
268 ciType *type;
269 switch (callee->return_type()->basic_type()) {
270 case T_BOOLEAN:
271 case T_BYTE:
272 case T_CHAR:
273 case T_SHORT:
274 type = ciType::make(T_INT);
275 break;
276
277 default:
278 type = callee->return_type();
279 }
280
281 push(SharkValue::create_generic(type, NULL, false));
282 }
283 SharkJavaCallCacher(function(), callee).scan(current_state());
284 }
285
286 void SharkTopLevelBlock::decache_for_VM_call() {
287 SharkVMCallDecacher(function(), bci()).scan(current_state());
288 }
289
290 void SharkTopLevelBlock::cache_after_VM_call() {
291 SharkVMCallCacher(function()).scan(current_state());
292 }
293
294 void SharkTopLevelBlock::decache_for_trap() {
295 SharkTrapDecacher(function(), bci()).scan(current_state());
296 }
297
298 void SharkTopLevelBlock::emit_IR() {
299 builder()->SetInsertPoint(entry_block());
300
301 // Parse the bytecode
302 parse_bytecode(start(), limit());
303
304 // If this block falls through to the next then it won't have been
305 // terminated by a bytecode and we have to add the branch ourselves
306 if (falls_through() && !has_trap())
307 do_branch(ciTypeFlow::FALL_THROUGH);
308 }
309
310 SharkTopLevelBlock* SharkTopLevelBlock::bci_successor(int bci) const {
311 // XXX now with Linear Search Technology (tm)
312 for (int i = 0; i < num_successors(); i++) {
313 ciTypeFlow::Block *successor = ciblock()->successors()->at(i);
314 if (successor->start() == bci)
315 return function()->block(successor->pre_order());
316 }
317 ShouldNotReachHere();
318 }
319
320 void SharkTopLevelBlock::do_zero_check(SharkValue *value) {
321 if (value->is_phi() && value->as_phi()->all_incomers_zero_checked()) {
322 function()->add_deferred_zero_check(this, value);
323 }
324 else {
325 BasicBlock *continue_block = function()->CreateBlock("not_zero");
326 SharkState *saved_state = current_state();
327 set_current_state(saved_state->copy());
328 zero_check_value(value, continue_block);
329 builder()->SetInsertPoint(continue_block);
330 set_current_state(saved_state);
331 }
332
333 value->set_zero_checked(true);
334 }
335
336 void SharkTopLevelBlock::do_deferred_zero_check(SharkValue* value,
337 int bci,
338 SharkState* saved_state,
339 BasicBlock* continue_block) {
340 if (value->as_phi()->all_incomers_zero_checked()) {
341 builder()->CreateBr(continue_block);
342 }
343 else {
344 iter()->force_bci(start());
345 set_current_state(saved_state);
346 zero_check_value(value, continue_block);
347 }
348 }
349
350 void SharkTopLevelBlock::zero_check_value(SharkValue* value,
351 BasicBlock* continue_block) {
352 BasicBlock *zero_block = builder()->CreateBlock(continue_block, "zero");
353
354 Value *a, *b;
355 switch (value->basic_type()) {
356 case T_BYTE:
357 case T_CHAR:
358 case T_SHORT:
359 case T_INT:
360 a = value->jint_value();
361 b = LLVMValue::jint_constant(0);
362 break;
363 case T_LONG:
364 a = value->jlong_value();
365 b = LLVMValue::jlong_constant(0);
366 break;
367 case T_OBJECT:
368 case T_ARRAY:
369 a = value->jobject_value();
370 b = LLVMValue::LLVMValue::null();
371 break;
372 default:
373 tty->print_cr("Unhandled type %s", type2name(value->basic_type()));
374 ShouldNotReachHere();
375 }
376
377 builder()->CreateCondBr(
378 builder()->CreateICmpNE(a, b), continue_block, zero_block);
379
380 builder()->SetInsertPoint(zero_block);
381 if (value->is_jobject()) {
382 call_vm(
383 builder()->throw_NullPointerException(),
384 builder()->CreateIntToPtr(
385 LLVMValue::intptr_constant((intptr_t) __FILE__),
386 PointerType::getUnqual(SharkType::jbyte_type())),
387 LLVMValue::jint_constant(__LINE__),
388 EX_CHECK_NONE);
389 }
390 else {
391 call_vm(
392 builder()->throw_ArithmeticException(),
393 builder()->CreateIntToPtr(
394 LLVMValue::intptr_constant((intptr_t) __FILE__),
395 PointerType::getUnqual(SharkType::jbyte_type())),
396 LLVMValue::jint_constant(__LINE__),
397 EX_CHECK_NONE);
398 }
399
400 Value *pending_exception = get_pending_exception();
401 clear_pending_exception();
402 handle_exception(pending_exception, EX_CHECK_FULL);
403 }
404
405 void SharkTopLevelBlock::check_bounds(SharkValue* array, SharkValue* index) {
406 BasicBlock *out_of_bounds = function()->CreateBlock("out_of_bounds");
407 BasicBlock *in_bounds = function()->CreateBlock("in_bounds");
408
409 Value *length = builder()->CreateArrayLength(array->jarray_value());
410 // we use an unsigned comparison to catch negative values
411 builder()->CreateCondBr(
412 builder()->CreateICmpULT(index->jint_value(), length),
413 in_bounds, out_of_bounds);
414
415 builder()->SetInsertPoint(out_of_bounds);
416 SharkState *saved_state = current_state()->copy();
417
418 call_vm(
419 builder()->throw_ArrayIndexOutOfBoundsException(),
420 builder()->CreateIntToPtr(
421 LLVMValue::intptr_constant((intptr_t) __FILE__),
422 PointerType::getUnqual(SharkType::jbyte_type())),
423 LLVMValue::jint_constant(__LINE__),
424 index->jint_value(),
425 EX_CHECK_NONE);
426
427 Value *pending_exception = get_pending_exception();
428 clear_pending_exception();
429 handle_exception(pending_exception, EX_CHECK_FULL);
430
431 set_current_state(saved_state);
432
433 builder()->SetInsertPoint(in_bounds);
434 }
435
436 void SharkTopLevelBlock::check_pending_exception(int action) {
437 assert(action & EAM_CHECK, "should be");
438
439 BasicBlock *exception = function()->CreateBlock("exception");
440 BasicBlock *no_exception = function()->CreateBlock("no_exception");
441
442 Value *pending_exception = get_pending_exception();
443 builder()->CreateCondBr(
444 builder()->CreateICmpEQ(pending_exception, LLVMValue::null()),
445 no_exception, exception);
446
447 builder()->SetInsertPoint(exception);
448 SharkState *saved_state = current_state()->copy();
449 if (action & EAM_MONITOR_FUDGE) {
450 // The top monitor is marked live, but the exception was thrown
451 // while setting it up so we need to mark it dead before we enter
452 // any exception handlers as they will not expect it to be there.
453 set_num_monitors(num_monitors() - 1);
454 action ^= EAM_MONITOR_FUDGE;
455 }
456 clear_pending_exception();
457 handle_exception(pending_exception, action);
458 set_current_state(saved_state);
459
460 builder()->SetInsertPoint(no_exception);
461 }
462
463 void SharkTopLevelBlock::compute_exceptions() {
464 ciExceptionHandlerStream str(target(), start());
465
466 int exc_count = str.count();
467 _exc_handlers = new GrowableArray<ciExceptionHandler*>(exc_count);
468 _exceptions = new GrowableArray<SharkTopLevelBlock*>(exc_count);
469
470 int index = 0;
471 for (; !str.is_done(); str.next()) {
472 ciExceptionHandler *handler = str.handler();
473 if (handler->handler_bci() == -1)
474 break;
475 _exc_handlers->append(handler);
476
477 // Try and get this exception's handler from typeflow. We should
478 // do it this way always, really, except that typeflow sometimes
479 // doesn't record exceptions, even loaded ones, and sometimes it
480 // returns them with a different handler bci. Why???
481 SharkTopLevelBlock *block = NULL;
482 ciInstanceKlass* klass;
483 if (handler->is_catch_all()) {
484 klass = java_lang_Throwable_klass();
485 }
486 else {
487 klass = handler->catch_klass();
488 }
489 for (int i = 0; i < ciblock()->exceptions()->length(); i++) {
490 if (klass == ciblock()->exc_klasses()->at(i)) {
491 block = function()->block(ciblock()->exceptions()->at(i)->pre_order());
492 if (block->start() == handler->handler_bci())
493 break;
494 else
495 block = NULL;
496 }
497 }
498
499 // If typeflow let us down then try and figure it out ourselves
500 if (block == NULL) {
501 for (int i = 0; i < function()->block_count(); i++) {
502 SharkTopLevelBlock *candidate = function()->block(i);
503 if (candidate->start() == handler->handler_bci()) {
504 if (block != NULL) {
505 NOT_PRODUCT(warning("there may be trouble ahead"));
506 block = NULL;
507 break;
508 }
509 block = candidate;
510 }
511 }
512 }
513 _exceptions->append(block);
514 }
515 }
516
517 void SharkTopLevelBlock::handle_exception(Value* exception, int action) {
518 if (action & EAM_HANDLE && num_exceptions() != 0) {
519 // Clear the stack and push the exception onto it
520 while (xstack_depth())
521 pop();
522 push(SharkValue::create_jobject(exception, true));
523
524 // Work out how many options we have to check
525 bool has_catch_all = exc_handler(num_exceptions() - 1)->is_catch_all();
526 int num_options = num_exceptions();
527 if (has_catch_all)
528 num_options--;
529
530 // Marshal any non-catch-all handlers
531 if (num_options > 0) {
532 bool all_loaded = true;
533 for (int i = 0; i < num_options; i++) {
534 if (!exc_handler(i)->catch_klass()->is_loaded()) {
535 all_loaded = false;
536 break;
537 }
538 }
539
540 if (all_loaded)
541 marshal_exception_fast(num_options);
542 else
543 marshal_exception_slow(num_options);
544 }
545
546 // Install the catch-all handler, if present
547 if (has_catch_all) {
548 SharkTopLevelBlock* handler = this->exception(num_options);
549 assert(handler != NULL, "catch-all handler cannot be unloaded");
550
551 builder()->CreateBr(handler->entry_block());
552 handler->add_incoming(current_state());
553 return;
554 }
555 }
556
557 // No exception handler was found; unwind and return
558 handle_return(T_VOID, exception);
559 }
560
561 void SharkTopLevelBlock::marshal_exception_fast(int num_options) {
562 Value *exception_klass = builder()->CreateValueOfStructEntry(
563 xstack(0)->jobject_value(),
564 in_ByteSize(oopDesc::klass_offset_in_bytes()),
565 SharkType::oop_type(),
566 "exception_klass");
567
568 for (int i = 0; i < num_options; i++) {
569 Value *check_klass =
570 builder()->CreateInlineOop(exc_handler(i)->catch_klass());
571
572 BasicBlock *not_exact = function()->CreateBlock("not_exact");
573 BasicBlock *not_subtype = function()->CreateBlock("not_subtype");
574
575 builder()->CreateCondBr(
576 builder()->CreateICmpEQ(check_klass, exception_klass),
577 handler_for_exception(i), not_exact);
578
579 builder()->SetInsertPoint(not_exact);
580 builder()->CreateCondBr(
581 builder()->CreateICmpNE(
582 builder()->CreateCall2(
583 builder()->is_subtype_of(), check_klass, exception_klass),
584 LLVMValue::jbyte_constant(0)),
585 handler_for_exception(i), not_subtype);
586
587 builder()->SetInsertPoint(not_subtype);
588 }
589 }
590
591 void SharkTopLevelBlock::marshal_exception_slow(int num_options) {
592 int *indexes = NEW_RESOURCE_ARRAY(int, num_options);
593 for (int i = 0; i < num_options; i++)
594 indexes[i] = exc_handler(i)->catch_klass_index();
595
596 Value *index = call_vm(
597 builder()->find_exception_handler(),
598 builder()->CreateInlineData(
599 indexes,
600 num_options * sizeof(int),
601 PointerType::getUnqual(SharkType::jint_type())),
602 LLVMValue::jint_constant(num_options),
603 EX_CHECK_NO_CATCH);
604
605 BasicBlock *no_handler = function()->CreateBlock("no_handler");
606 SwitchInst *switchinst = builder()->CreateSwitch(
607 index, no_handler, num_options);
608
609 for (int i = 0; i < num_options; i++) {
610 switchinst->addCase(
611 LLVMValue::jint_constant(i),
612 handler_for_exception(i));
613 }
614
615 builder()->SetInsertPoint(no_handler);
616 }
617
618 BasicBlock* SharkTopLevelBlock::handler_for_exception(int index) {
619 SharkTopLevelBlock *successor = this->exception(index);
620 if (successor) {
621 successor->add_incoming(current_state());
622 return successor->entry_block();
623 }
624 else {
625 return make_trap(
626 exc_handler(index)->handler_bci(),
627 Deoptimization::make_trap_request(
628 Deoptimization::Reason_unhandled,
629 Deoptimization::Action_reinterpret));
630 }
631 }
632
633 void SharkTopLevelBlock::maybe_add_safepoint() {
634 if (current_state()->has_safepointed())
635 return;
636
637 BasicBlock *orig_block = builder()->GetInsertBlock();
638 SharkState *orig_state = current_state()->copy();
639
640 BasicBlock *do_safepoint = function()->CreateBlock("do_safepoint");
641 BasicBlock *safepointed = function()->CreateBlock("safepointed");
642
643 Value *state = builder()->CreateLoad(
644 builder()->CreateIntToPtr(
645 LLVMValue::intptr_constant(
646 (intptr_t) SafepointSynchronize::address_of_state()),
647 PointerType::getUnqual(SharkType::jint_type())),
648 "state");
649
650 builder()->CreateCondBr(
651 builder()->CreateICmpEQ(
652 state,
653 LLVMValue::jint_constant(SafepointSynchronize::_synchronizing)),
654 do_safepoint, safepointed);
655
656 builder()->SetInsertPoint(do_safepoint);
657 call_vm(builder()->safepoint(), EX_CHECK_FULL);
658 BasicBlock *safepointed_block = builder()->GetInsertBlock();
659 builder()->CreateBr(safepointed);
660
661 builder()->SetInsertPoint(safepointed);
662 current_state()->merge(orig_state, orig_block, safepointed_block);
663
664 current_state()->set_has_safepointed(true);
665 }
666
667 void SharkTopLevelBlock::maybe_add_backedge_safepoint() {
668 if (current_state()->has_safepointed())
669 return;
670
671 for (int i = 0; i < num_successors(); i++) {
672 if (successor(i)->can_reach(this)) {
673 maybe_add_safepoint();
674 break;
675 }
676 }
677 }
678
679 bool SharkTopLevelBlock::can_reach(SharkTopLevelBlock* other) {
680 for (int i = 0; i < function()->block_count(); i++)
681 function()->block(i)->_can_reach_visited = false;
682
683 return can_reach_helper(other);
684 }
685
686 bool SharkTopLevelBlock::can_reach_helper(SharkTopLevelBlock* other) {
687 if (this == other)
688 return true;
689
690 if (_can_reach_visited)
691 return false;
692 _can_reach_visited = true;
693
694 if (!has_trap()) {
695 for (int i = 0; i < num_successors(); i++) {
696 if (successor(i)->can_reach_helper(other))
697 return true;
698 }
699 }
700
701 for (int i = 0; i < num_exceptions(); i++) {
702 SharkTopLevelBlock *handler = exception(i);
703 if (handler && handler->can_reach_helper(other))
704 return true;
705 }
706
707 return false;
708 }
709
710 BasicBlock* SharkTopLevelBlock::make_trap(int trap_bci, int trap_request) {
711 BasicBlock *trap_block = function()->CreateBlock("trap");
712 BasicBlock *orig_block = builder()->GetInsertBlock();
713 builder()->SetInsertPoint(trap_block);
714
715 int orig_bci = bci();
716 iter()->force_bci(trap_bci);
717
718 do_trap(trap_request);
719
720 builder()->SetInsertPoint(orig_block);
721 iter()->force_bci(orig_bci);
722
723 return trap_block;
724 }
725
726 void SharkTopLevelBlock::do_trap(int trap_request) {
727 decache_for_trap();
728 builder()->CreateRet(
729 builder()->CreateCall2(
730 builder()->uncommon_trap(),
731 thread(),
732 LLVMValue::jint_constant(trap_request)));
733 }
734
735 void SharkTopLevelBlock::call_register_finalizer(Value *receiver) {
736 BasicBlock *orig_block = builder()->GetInsertBlock();
737 SharkState *orig_state = current_state()->copy();
738
739 BasicBlock *do_call = function()->CreateBlock("has_finalizer");
740 BasicBlock *done = function()->CreateBlock("done");
741
742 Value *klass = builder()->CreateValueOfStructEntry(
743 receiver,
744 in_ByteSize(oopDesc::klass_offset_in_bytes()),
745 SharkType::oop_type(),
746 "klass");
747
748 Value *access_flags = builder()->CreateValueOfStructEntry(
749 klass,
750 Klass::access_flags_offset(),
751 SharkType::jint_type(),
752 "access_flags");
753
754 builder()->CreateCondBr(
755 builder()->CreateICmpNE(
756 builder()->CreateAnd(
757 access_flags,
758 LLVMValue::jint_constant(JVM_ACC_HAS_FINALIZER)),
759 LLVMValue::jint_constant(0)),
760 do_call, done);
761
762 builder()->SetInsertPoint(do_call);
763 call_vm(builder()->register_finalizer(), receiver, EX_CHECK_FULL);
764 BasicBlock *branch_block = builder()->GetInsertBlock();
765 builder()->CreateBr(done);
766
767 builder()->SetInsertPoint(done);
768 current_state()->merge(orig_state, orig_block, branch_block);
769 }
770
771 void SharkTopLevelBlock::handle_return(BasicType type, Value* exception) {
772 assert (exception == NULL || type == T_VOID, "exception OR result, please");
773
774 if (num_monitors()) {
775 // Protect our exception across possible monitor release decaches
776 if (exception)
777 set_oop_tmp(exception);
778
779 // We don't need to check for exceptions thrown here. If
780 // we're returning a value then we just carry on as normal:
781 // the caller will see the pending exception and handle it.
782 // If we're returning with an exception then that exception
783 // takes priority and the release_lock one will be ignored.
784 while (num_monitors())
785 release_lock(EX_CHECK_NONE);
786
787 // Reload the exception we're throwing
788 if (exception)
789 exception = get_oop_tmp();
790 }
791
792 if (exception) {
793 builder()->CreateStore(exception, pending_exception_address());
794 }
795
796 Value *result_addr = stack()->CreatePopFrame(type2size[type]);
797 if (type != T_VOID) {
798 builder()->CreateStore(
799 pop_result(type)->generic_value(),
800 builder()->CreateIntToPtr(
801 result_addr,
802 PointerType::getUnqual(SharkType::to_stackType(type))));
803 }
804
805 builder()->CreateRet(LLVMValue::jint_constant(0));
806 }
807
808 void SharkTopLevelBlock::do_arraylength() {
809 SharkValue *array = pop();
810 check_null(array);
811 Value *length = builder()->CreateArrayLength(array->jarray_value());
812 push(SharkValue::create_jint(length, false));
813 }
814
815 void SharkTopLevelBlock::do_aload(BasicType basic_type) {
816 SharkValue *index = pop();
817 SharkValue *array = pop();
818
819 check_null(array);
820 check_bounds(array, index);
821
822 Value *value = builder()->CreateLoad(
823 builder()->CreateArrayAddress(
824 array->jarray_value(), basic_type, index->jint_value()));
825
826 const Type *stack_type = SharkType::to_stackType(basic_type);
827 if (value->getType() != stack_type)
828 value = builder()->CreateIntCast(value, stack_type, basic_type != T_CHAR);
829
830 switch (basic_type) {
831 case T_BYTE:
832 case T_CHAR:
833 case T_SHORT:
834 case T_INT:
835 push(SharkValue::create_jint(value, false));
836 break;
837
838 case T_LONG:
839 push(SharkValue::create_jlong(value, false));
840 break;
841
842 case T_FLOAT:
843 push(SharkValue::create_jfloat(value));
844 break;
845
846 case T_DOUBLE:
847 push(SharkValue::create_jdouble(value));
848 break;
849
850 case T_OBJECT:
851 // You might expect that array->type()->is_array_klass() would
852 // always be true, but it isn't. If ciTypeFlow detects that a
853 // value is always null then that value becomes an untyped null
854 // object. Shark doesn't presently support this, so a generic
855 // T_OBJECT is created. In this case we guess the type using
856 // the BasicType we were supplied. In reality the generated
857 // code will never be used, as the null value will be caught
858 // by the above null pointer check.
859 // http://icedtea.classpath.org/bugzilla/show_bug.cgi?id=324
860 push(
861 SharkValue::create_generic(
862 array->type()->is_array_klass() ?
863 ((ciArrayKlass *) array->type())->element_type() :
864 ciType::make(basic_type),
865 value, false));
866 break;
867
868 default:
869 tty->print_cr("Unhandled type %s", type2name(basic_type));
870 ShouldNotReachHere();
871 }
872 }
873
874 void SharkTopLevelBlock::do_astore(BasicType basic_type) {
875 SharkValue *svalue = pop();
876 SharkValue *index = pop();
877 SharkValue *array = pop();
878
879 check_null(array);
880 check_bounds(array, index);
881
882 Value *value;
883 switch (basic_type) {
884 case T_BYTE:
885 case T_CHAR:
886 case T_SHORT:
887 case T_INT:
888 value = svalue->jint_value();
889 break;
890
891 case T_LONG:
892 value = svalue->jlong_value();
893 break;
894
895 case T_FLOAT:
896 value = svalue->jfloat_value();
897 break;
898
899 case T_DOUBLE:
900 value = svalue->jdouble_value();
901 break;
902
903 case T_OBJECT:
904 value = svalue->jobject_value();
905 // XXX assignability check
906 break;
907
908 default:
909 tty->print_cr("Unhandled type %s", type2name(basic_type));
910 ShouldNotReachHere();
911 }
912
913 const Type *array_type = SharkType::to_arrayType(basic_type);
914 if (value->getType() != array_type)
915 value = builder()->CreateIntCast(value, array_type, basic_type != T_CHAR);
916
917 Value *addr = builder()->CreateArrayAddress(
918 array->jarray_value(), basic_type, index->jint_value(), "addr");
919
920 builder()->CreateStore(value, addr);
921
922 if (basic_type == T_OBJECT) // XXX or T_ARRAY?
923 builder()->CreateUpdateBarrierSet(oopDesc::bs(), addr);
924 }
925
926 void SharkTopLevelBlock::do_return(BasicType type) {
927 if (target()->intrinsic_id() == vmIntrinsics::_Object_init)
928 call_register_finalizer(local(0)->jobject_value());
929 maybe_add_safepoint();
930 handle_return(type, NULL);
931 }
932
933 void SharkTopLevelBlock::do_athrow() {
934 SharkValue *exception = pop();
935 check_null(exception);
936 handle_exception(exception->jobject_value(), EX_CHECK_FULL);
937 }
938
939 void SharkTopLevelBlock::do_goto() {
940 do_branch(ciTypeFlow::GOTO_TARGET);
941 }
942
943 void SharkTopLevelBlock::do_jsr() {
944 push(SharkValue::address_constant(iter()->next_bci()));
945 do_branch(ciTypeFlow::GOTO_TARGET);
946 }
947
948 void SharkTopLevelBlock::do_ret() {
949 assert(local(iter()->get_index())->address_value() ==
950 successor(ciTypeFlow::GOTO_TARGET)->start(), "should be");
951 do_branch(ciTypeFlow::GOTO_TARGET);
952 }
953
954 // All propagation of state from one block to the next (via
955 // dest->add_incoming) is handled by these methods:
956 // do_branch
957 // do_if_helper
958 // do_switch
959 // handle_exception
960
961 void SharkTopLevelBlock::do_branch(int successor_index) {
962 SharkTopLevelBlock *dest = successor(successor_index);
963 builder()->CreateBr(dest->entry_block());
964 dest->add_incoming(current_state());
965 }
966
967 void SharkTopLevelBlock::do_if(ICmpInst::Predicate p,
968 SharkValue* b,
969 SharkValue* a) {
970 Value *llvm_a, *llvm_b;
971 if (a->is_jobject()) {
972 llvm_a = a->intptr_value(builder());
973 llvm_b = b->intptr_value(builder());
974 }
975 else {
976 llvm_a = a->jint_value();
977 llvm_b = b->jint_value();
978 }
979 do_if_helper(p, llvm_b, llvm_a, current_state(), current_state());
980 }
981
982 void SharkTopLevelBlock::do_if_helper(ICmpInst::Predicate p,
983 Value* b,
984 Value* a,
985 SharkState* if_taken_state,
986 SharkState* not_taken_state) {
987 SharkTopLevelBlock *if_taken = successor(ciTypeFlow::IF_TAKEN);
988 SharkTopLevelBlock *not_taken = successor(ciTypeFlow::IF_NOT_TAKEN);
989
990 builder()->CreateCondBr(
991 builder()->CreateICmp(p, a, b),
992 if_taken->entry_block(), not_taken->entry_block());
993
994 if_taken->add_incoming(if_taken_state);
995 not_taken->add_incoming(not_taken_state);
996 }
997
998 void SharkTopLevelBlock::do_switch() {
999 int len = switch_table_length();
1000
1001 SharkTopLevelBlock *dest_block = successor(ciTypeFlow::SWITCH_DEFAULT);
1002 SwitchInst *switchinst = builder()->CreateSwitch(
1003 pop()->jint_value(), dest_block->entry_block(), len);
1004 dest_block->add_incoming(current_state());
1005
1006 for (int i = 0; i < len; i++) {
1007 int dest_bci = switch_dest(i);
1008 if (dest_bci != switch_default_dest()) {
1009 dest_block = bci_successor(dest_bci);
1010 switchinst->addCase(
1011 LLVMValue::jint_constant(switch_key(i)),
1012 dest_block->entry_block());
1013 dest_block->add_incoming(current_state());
1014 }
1015 }
1016 }
1017
1018 ciMethod* SharkTopLevelBlock::improve_virtual_call(ciMethod* caller,
1019 ciInstanceKlass* klass,
1020 ciMethod* dest_method,
1021 ciType* receiver_type) {
1022 // If the method is obviously final then we are already done
1023 if (dest_method->can_be_statically_bound())
1024 return dest_method;
1025
1026 // Array methods are all inherited from Object and are monomorphic
1027 if (receiver_type->is_array_klass() &&
1028 dest_method->holder() == java_lang_Object_klass())
1029 return dest_method;
1030
1031 #ifdef SHARK_CAN_DEOPTIMIZE_ANYWHERE
1032 // This code can replace a virtual call with a direct call if this
1033 // class is the only one in the entire set of loaded classes that
1034 // implements this method. This makes the compiled code dependent
1035 // on other classes that implement the method not being loaded, a
1036 // condition which is enforced by the dependency tracker. If the
1037 // dependency tracker determines a method has become invalid it
1038 // will mark it for recompilation, causing running copies to be
1039 // deoptimized. Shark currently can't deoptimize arbitrarily like
1040 // that, so this optimization cannot be used.
1041 // http://icedtea.classpath.org/bugzilla/show_bug.cgi?id=481
1042
1043 // All other interesting cases are instance classes
1044 if (!receiver_type->is_instance_klass())
1045 return NULL;
1046
1047 // Attempt to improve the receiver
1048 ciInstanceKlass* actual_receiver = klass;
1049 ciInstanceKlass *improved_receiver = receiver_type->as_instance_klass();
1050 if (improved_receiver->is_loaded() &&
1051 improved_receiver->is_initialized() &&
1052 !improved_receiver->is_interface() &&
1053 improved_receiver->is_subtype_of(actual_receiver)) {
1054 actual_receiver = improved_receiver;
1055 }
1056
1057 // Attempt to find a monomorphic target for this call using
1058 // class heirachy analysis.
1059 ciInstanceKlass *calling_klass = caller->holder();
1060 ciMethod* monomorphic_target =
1061 dest_method->find_monomorphic_target(calling_klass, klass, actual_receiver);
1062 if (monomorphic_target != NULL) {
1063 assert(!monomorphic_target->is_abstract(), "shouldn't be");
1064
1065 // Opto has a bunch of type checking here that I don't
1066 // understand. It's to inhibit casting in one direction,
1067 // possibly because objects in Opto can have inexact
1068 // types, but I can't even tell which direction it
1069 // doesn't like. For now I'm going to block *any* cast.
1070 if (monomorphic_target != dest_method) {
1071 if (SharkPerformanceWarnings) {
1072 warning("found monomorphic target, but inhibited cast:");
1073 tty->print(" dest_method = ");
1074 dest_method->print_short_name(tty);
1075 tty->cr();
1076 tty->print(" monomorphic_target = ");
1077 monomorphic_target->print_short_name(tty);
1078 tty->cr();
1079 }
1080 monomorphic_target = NULL;
1081 }
1082 }
1083
1084 // Replace the virtual call with a direct one. This makes
1085 // us dependent on that target method not getting overridden
1086 // by dynamic class loading.
1087 if (monomorphic_target != NULL) {
1088 dependencies()->assert_unique_concrete_method(
1089 actual_receiver, monomorphic_target);
1090 return monomorphic_target;
1091 }
1092
1093 // Because Opto distinguishes exact types from inexact ones
1094 // it can perform a further optimization to replace calls
1095 // with non-monomorphic targets if the receiver has an exact
1096 // type. We don't mark types this way, so we can't do this.
1097
1098 #endif // SHARK_CAN_DEOPTIMIZE_ANYWHERE
1099
1100 return NULL;
1101 }
1102
1103 Value *SharkTopLevelBlock::get_direct_callee(ciMethod* method) {
1104 return builder()->CreateBitCast(
1105 builder()->CreateInlineOop(method),
1106 SharkType::Method*_type(),
1107 "callee");
1108 }
1109
1110 Value *SharkTopLevelBlock::get_virtual_callee(SharkValue* receiver,
1111 int vtable_index) {
1112 Value *klass = builder()->CreateValueOfStructEntry(
1113 receiver->jobject_value(),
1114 in_ByteSize(oopDesc::klass_offset_in_bytes()),
1115 SharkType::oop_type(),
1116 "klass");
1117
1118 return builder()->CreateLoad(
1119 builder()->CreateArrayAddress(
1120 klass,
1121 SharkType::Method*_type(),
1122 vtableEntry::size() * wordSize,
1123 in_ByteSize(InstanceKlass::vtable_start_offset() * wordSize),
1124 LLVMValue::intptr_constant(vtable_index)),
1125 "callee");
1126 }
1127
1128 Value* SharkTopLevelBlock::get_interface_callee(SharkValue *receiver,
1129 ciMethod* method) {
1130 BasicBlock *loop = function()->CreateBlock("loop");
1131 BasicBlock *got_null = function()->CreateBlock("got_null");
1132 BasicBlock *not_null = function()->CreateBlock("not_null");
1133 BasicBlock *next = function()->CreateBlock("next");
1134 BasicBlock *got_entry = function()->CreateBlock("got_entry");
1135
1136 // Locate the receiver's itable
1137 Value *object_klass = builder()->CreateValueOfStructEntry(
1138 receiver->jobject_value(), in_ByteSize(oopDesc::klass_offset_in_bytes()),
1139 SharkType::oop_type(),
1140 "object_klass");
1141
1142 Value *vtable_start = builder()->CreateAdd(
1143 builder()->CreatePtrToInt(object_klass, SharkType::intptr_type()),
1144 LLVMValue::intptr_constant(
1145 InstanceKlass::vtable_start_offset() * HeapWordSize),
1146 "vtable_start");
1147
1148 Value *vtable_length = builder()->CreateValueOfStructEntry(
1149 object_klass,
1150 in_ByteSize(InstanceKlass::vtable_length_offset() * HeapWordSize),
1151 SharkType::jint_type(),
1152 "vtable_length");
1153 vtable_length =
1154 builder()->CreateIntCast(vtable_length, SharkType::intptr_type(), false);
1155
1156 bool needs_aligning = HeapWordsPerLong > 1;
1157 Value *itable_start = builder()->CreateAdd(
1158 vtable_start,
1159 builder()->CreateShl(
1160 vtable_length,
1161 LLVMValue::intptr_constant(exact_log2(vtableEntry::size() * wordSize))),
1162 needs_aligning ? "" : "itable_start");
1163 if (needs_aligning) {
1164 itable_start = builder()->CreateAnd(
1165 builder()->CreateAdd(
1166 itable_start, LLVMValue::intptr_constant(BytesPerLong - 1)),
1167 LLVMValue::intptr_constant(~(BytesPerLong - 1)),
1168 "itable_start");
1169 }
1170
1171 // Locate this interface's entry in the table
1172 Value *iklass = builder()->CreateInlineOop(method->holder());
1173 BasicBlock *loop_entry = builder()->GetInsertBlock();
1174 builder()->CreateBr(loop);
1175 builder()->SetInsertPoint(loop);
1176 PHINode *itable_entry_addr = builder()->CreatePHI(
1177 SharkType::intptr_type(), "itable_entry_addr");
1178 itable_entry_addr->addIncoming(itable_start, loop_entry);
1179
1180 Value *itable_entry = builder()->CreateIntToPtr(
1181 itable_entry_addr, SharkType::itableOffsetEntry_type(), "itable_entry");
1182
1183 Value *itable_iklass = builder()->CreateValueOfStructEntry(
1184 itable_entry,
1185 in_ByteSize(itableOffsetEntry::interface_offset_in_bytes()),
1186 SharkType::oop_type(),
1187 "itable_iklass");
1188
1189 builder()->CreateCondBr(
1190 builder()->CreateICmpEQ(itable_iklass, LLVMValue::null()),
1191 got_null, not_null);
1192
1193 // A null entry means that the class doesn't implement the
1194 // interface, and wasn't the same as the class checked when
1195 // the interface was resolved.
1196 builder()->SetInsertPoint(got_null);
1197 builder()->CreateUnimplemented(__FILE__, __LINE__);
1198 builder()->CreateUnreachable();
1199
1200 builder()->SetInsertPoint(not_null);
1201 builder()->CreateCondBr(
1202 builder()->CreateICmpEQ(itable_iklass, iklass),
1203 got_entry, next);
1204
1205 builder()->SetInsertPoint(next);
1206 Value *next_entry = builder()->CreateAdd(
1207 itable_entry_addr,
1208 LLVMValue::intptr_constant(itableOffsetEntry::size() * wordSize));
1209 builder()->CreateBr(loop);
1210 itable_entry_addr->addIncoming(next_entry, next);
1211
1212 // Locate the method pointer
1213 builder()->SetInsertPoint(got_entry);
1214 Value *offset = builder()->CreateValueOfStructEntry(
1215 itable_entry,
1216 in_ByteSize(itableOffsetEntry::offset_offset_in_bytes()),
1217 SharkType::jint_type(),
1218 "offset");
1219 offset =
1220 builder()->CreateIntCast(offset, SharkType::intptr_type(), false);
1221
1222 return builder()->CreateLoad(
1223 builder()->CreateIntToPtr(
1224 builder()->CreateAdd(
1225 builder()->CreateAdd(
1226 builder()->CreateAdd(
1227 builder()->CreatePtrToInt(
1228 object_klass, SharkType::intptr_type()),
1229 offset),
1230 LLVMValue::intptr_constant(
1231 method->itable_index() * itableMethodEntry::size() * wordSize)),
1232 LLVMValue::intptr_constant(
1233 itableMethodEntry::method_offset_in_bytes())),
1234 PointerType::getUnqual(SharkType::Method*_type())),
1235 "callee");
1236 }
1237
1238 void SharkTopLevelBlock::do_call() {
1239 // Set frequently used booleans
1240 bool is_static = bc() == Bytecodes::_invokestatic;
1241 bool is_virtual = bc() == Bytecodes::_invokevirtual;
1242 bool is_interface = bc() == Bytecodes::_invokeinterface;
1243
1244 // Find the method being called
1245 bool will_link;
1246 ciMethod *dest_method = iter()->get_method(will_link);
1247 assert(will_link, "typeflow responsibility");
1248 assert(dest_method->is_static() == is_static, "must match bc");
1249
1250 // Find the class of the method being called. Note
1251 // that the superclass check in the second assertion
1252 // is to cope with a hole in the spec that allows for
1253 // invokeinterface instructions where the resolved
1254 // method is a virtual method in java.lang.Object.
1255 // javac doesn't generate code like that, but there's
1256 // no reason a compliant Java compiler might not.
1257 ciInstanceKlass *holder_klass = dest_method->holder();
1258 assert(holder_klass->is_loaded(), "scan_for_traps responsibility");
1259 assert(holder_klass->is_interface() ||
1260 holder_klass->super() == NULL ||
1261 !is_interface, "must match bc");
1262 ciKlass *holder = iter()->get_declared_method_holder();
1263 ciInstanceKlass *klass =
1264 ciEnv::get_instance_klass_for_declared_method_holder(holder);
1265
1266 // Find the receiver in the stack. We do this before
1267 // trying to inline because the inliner can only use
1268 // zero-checked values, not being able to perform the
1269 // check itself.
1270 SharkValue *receiver = NULL;
1271 if (!is_static) {
1272 receiver = xstack(dest_method->arg_size() - 1);
1273 check_null(receiver);
1274 }
1275
1276 // Try to improve non-direct calls
1277 bool call_is_virtual = is_virtual || is_interface;
1278 ciMethod *call_method = dest_method;
1279 if (call_is_virtual) {
1280 ciMethod *optimized_method = improve_virtual_call(
1281 target(), klass, dest_method, receiver->type());
1282 if (optimized_method) {
1283 call_method = optimized_method;
1284 call_is_virtual = false;
1285 }
1286 }
1287
1288 // Try to inline the call
1289 if (!call_is_virtual) {
1290 if (SharkInliner::attempt_inline(call_method, current_state()))
1291 return;
1292 }
1293
1294 // Find the method we are calling
1295 Value *callee;
1296 if (call_is_virtual) {
1297 if (is_virtual) {
1298 assert(klass->is_linked(), "scan_for_traps responsibility");
1299 int vtable_index = call_method->resolve_vtable_index(
1300 target()->holder(), klass);
1301 assert(vtable_index >= 0, "should be");
1302 callee = get_virtual_callee(receiver, vtable_index);
1303 }
1304 else {
1305 assert(is_interface, "should be");
1306 callee = get_interface_callee(receiver, call_method);
1307 }
1308 }
1309 else {
1310 callee = get_direct_callee(call_method);
1311 }
1312
1313 // Load the SharkEntry from the callee
1314 Value *base_pc = builder()->CreateValueOfStructEntry(
1315 callee, Method::from_interpreted_offset(),
1316 SharkType::intptr_type(),
1317 "base_pc");
1318
1319 // Load the entry point from the SharkEntry
1320 Value *entry_point = builder()->CreateLoad(
1321 builder()->CreateIntToPtr(
1322 builder()->CreateAdd(
1323 base_pc,
1324 LLVMValue::intptr_constant(in_bytes(ZeroEntry::entry_point_offset()))),
1325 PointerType::getUnqual(
1326 PointerType::getUnqual(SharkType::entry_point_type()))),
1327 "entry_point");
1328
1329 // Make the call
1330 decache_for_Java_call(call_method);
1331 Value *deoptimized_frames = builder()->CreateCall3(
1332 entry_point, callee, base_pc, thread());
1333
1334 // If the callee got deoptimized then reexecute in the interpreter
1335 BasicBlock *reexecute = function()->CreateBlock("reexecute");
1336 BasicBlock *call_completed = function()->CreateBlock("call_completed");
1337 builder()->CreateCondBr(
1338 builder()->CreateICmpNE(deoptimized_frames, LLVMValue::jint_constant(0)),
1339 reexecute, call_completed);
1340
1341 builder()->SetInsertPoint(reexecute);
1342 builder()->CreateCall2(
1343 builder()->deoptimized_entry_point(),
1344 builder()->CreateSub(deoptimized_frames, LLVMValue::jint_constant(1)),
1345 thread());
1346 builder()->CreateBr(call_completed);
1347
1348 // Cache after the call
1349 builder()->SetInsertPoint(call_completed);
1350 cache_after_Java_call(call_method);
1351
1352 // Check for pending exceptions
1353 check_pending_exception(EX_CHECK_FULL);
1354
1355 // Mark that a safepoint check has occurred
1356 current_state()->set_has_safepointed(true);
1357 }
1358
1359 bool SharkTopLevelBlock::static_subtype_check(ciKlass* check_klass,
1360 ciKlass* object_klass) {
1361 // If the class we're checking against is java.lang.Object
1362 // then this is a no brainer. Apparently this can happen
1363 // in reflective code...
1364 if (check_klass == java_lang_Object_klass())
1365 return true;
1366
1367 // Perform a subtype check. NB in opto's code for this
1368 // (GraphKit::static_subtype_check) it says that static
1369 // interface types cannot be trusted, and if opto can't
1370 // trust them then I assume we can't either.
1371 if (object_klass->is_loaded() && !object_klass->is_interface()) {
1372 if (object_klass == check_klass)
1373 return true;
1374
1375 if (check_klass->is_loaded() && object_klass->is_subtype_of(check_klass))
1376 return true;
1377 }
1378
1379 return false;
1380 }
1381
1382 void SharkTopLevelBlock::do_instance_check() {
1383 // Get the class we're checking against
1384 bool will_link;
1385 ciKlass *check_klass = iter()->get_klass(will_link);
1386
1387 // Get the class of the object we're checking
1388 ciKlass *object_klass = xstack(0)->type()->as_klass();
1389
1390 // Can we optimize this check away?
1391 if (static_subtype_check(check_klass, object_klass)) {
1392 if (bc() == Bytecodes::_instanceof) {
1393 pop();
1394 push(SharkValue::jint_constant(1));
1395 }
1396 return;
1397 }
1398
1399 // Need to check this one at runtime
1400 if (will_link)
1401 do_full_instance_check(check_klass);
1402 else
1403 do_trapping_instance_check(check_klass);
1404 }
1405
1406 bool SharkTopLevelBlock::maybe_do_instanceof_if() {
1407 // Get the class we're checking against
1408 bool will_link;
1409 ciKlass *check_klass = iter()->get_klass(will_link);
1410
1411 // If the class is unloaded then the instanceof
1412 // cannot possibly succeed.
1413 if (!will_link)
1414 return false;
1415
1416 // Keep a copy of the object we're checking
1417 SharkValue *old_object = xstack(0);
1418
1419 // Get the class of the object we're checking
1420 ciKlass *object_klass = old_object->type()->as_klass();
1421
1422 // If the instanceof can be optimized away at compile time
1423 // then any subsequent checkcasts will be too so we handle
1424 // it normally.
1425 if (static_subtype_check(check_klass, object_klass))
1426 return false;
1427
1428 // Perform the instance check
1429 do_full_instance_check(check_klass);
1430 Value *result = pop()->jint_value();
1431
1432 // Create the casted object
1433 SharkValue *new_object = SharkValue::create_generic(
1434 check_klass, old_object->jobject_value(), old_object->zero_checked());
1435
1436 // Create two copies of the current state, one with the
1437 // original object and one with all instances of the
1438 // original object replaced with the new, casted object.
1439 SharkState *new_state = current_state();
1440 SharkState *old_state = new_state->copy();
1441 new_state->replace_all(old_object, new_object);
1442
1443 // Perform the check-and-branch
1444 switch (iter()->next_bc()) {
1445 case Bytecodes::_ifeq:
1446 // branch if not an instance
1447 do_if_helper(
1448 ICmpInst::ICMP_EQ,
1449 LLVMValue::jint_constant(0), result,
1450 old_state, new_state);
1451 break;
1452
1453 case Bytecodes::_ifne:
1454 // branch if an instance
1455 do_if_helper(
1456 ICmpInst::ICMP_NE,
1457 LLVMValue::jint_constant(0), result,
1458 new_state, old_state);
1459 break;
1460
1461 default:
1462 ShouldNotReachHere();
1463 }
1464
1465 return true;
1466 }
1467
1468 void SharkTopLevelBlock::do_full_instance_check(ciKlass* klass) {
1469 BasicBlock *not_null = function()->CreateBlock("not_null");
1470 BasicBlock *subtype_check = function()->CreateBlock("subtype_check");
1471 BasicBlock *is_instance = function()->CreateBlock("is_instance");
1472 BasicBlock *not_instance = function()->CreateBlock("not_instance");
1473 BasicBlock *merge1 = function()->CreateBlock("merge1");
1474 BasicBlock *merge2 = function()->CreateBlock("merge2");
1475
1476 enum InstanceCheckStates {
1477 IC_IS_NULL,
1478 IC_IS_INSTANCE,
1479 IC_NOT_INSTANCE,
1480 };
1481
1482 // Pop the object off the stack
1483 Value *object = pop()->jobject_value();
1484
1485 // Null objects aren't instances of anything
1486 builder()->CreateCondBr(
1487 builder()->CreateICmpEQ(object, LLVMValue::null()),
1488 merge2, not_null);
1489 BasicBlock *null_block = builder()->GetInsertBlock();
1490
1491 // Get the class we're checking against
1492 builder()->SetInsertPoint(not_null);
1493 Value *check_klass = builder()->CreateInlineOop(klass);
1494
1495 // Get the class of the object being tested
1496 Value *object_klass = builder()->CreateValueOfStructEntry(
1497 object, in_ByteSize(oopDesc::klass_offset_in_bytes()),
1498 SharkType::oop_type(),
1499 "object_klass");
1500
1501 // Perform the check
1502 builder()->CreateCondBr(
1503 builder()->CreateICmpEQ(check_klass, object_klass),
1504 is_instance, subtype_check);
1505
1506 builder()->SetInsertPoint(subtype_check);
1507 builder()->CreateCondBr(
1508 builder()->CreateICmpNE(
1509 builder()->CreateCall2(
1510 builder()->is_subtype_of(), check_klass, object_klass),
1511 LLVMValue::jbyte_constant(0)),
1512 is_instance, not_instance);
1513
1514 builder()->SetInsertPoint(is_instance);
1515 builder()->CreateBr(merge1);
1516
1517 builder()->SetInsertPoint(not_instance);
1518 builder()->CreateBr(merge1);
1519
1520 // First merge
1521 builder()->SetInsertPoint(merge1);
1522 PHINode *nonnull_result = builder()->CreatePHI(
1523 SharkType::jint_type(), "nonnull_result");
1524 nonnull_result->addIncoming(
1525 LLVMValue::jint_constant(IC_IS_INSTANCE), is_instance);
1526 nonnull_result->addIncoming(
1527 LLVMValue::jint_constant(IC_NOT_INSTANCE), not_instance);
1528 BasicBlock *nonnull_block = builder()->GetInsertBlock();
1529 builder()->CreateBr(merge2);
1530
1531 // Second merge
1532 builder()->SetInsertPoint(merge2);
1533 PHINode *result = builder()->CreatePHI(
1534 SharkType::jint_type(), "result");
1535 result->addIncoming(LLVMValue::jint_constant(IC_IS_NULL), null_block);
1536 result->addIncoming(nonnull_result, nonnull_block);
1537
1538 // Handle the result
1539 if (bc() == Bytecodes::_checkcast) {
1540 BasicBlock *failure = function()->CreateBlock("failure");
1541 BasicBlock *success = function()->CreateBlock("success");
1542
1543 builder()->CreateCondBr(
1544 builder()->CreateICmpNE(
1545 result, LLVMValue::jint_constant(IC_NOT_INSTANCE)),
1546 success, failure);
1547
1548 builder()->SetInsertPoint(failure);
1549 SharkState *saved_state = current_state()->copy();
1550
1551 call_vm(
1552 builder()->throw_ClassCastException(),
1553 builder()->CreateIntToPtr(
1554 LLVMValue::intptr_constant((intptr_t) __FILE__),
1555 PointerType::getUnqual(SharkType::jbyte_type())),
1556 LLVMValue::jint_constant(__LINE__),
1557 EX_CHECK_NONE);
1558
1559 Value *pending_exception = get_pending_exception();
1560 clear_pending_exception();
1561 handle_exception(pending_exception, EX_CHECK_FULL);
1562
1563 set_current_state(saved_state);
1564 builder()->SetInsertPoint(success);
1565 push(SharkValue::create_generic(klass, object, false));
1566 }
1567 else {
1568 push(
1569 SharkValue::create_jint(
1570 builder()->CreateIntCast(
1571 builder()->CreateICmpEQ(
1572 result, LLVMValue::jint_constant(IC_IS_INSTANCE)),
1573 SharkType::jint_type(), false), false));
1574 }
1575 }
1576
1577 void SharkTopLevelBlock::do_trapping_instance_check(ciKlass* klass) {
1578 BasicBlock *not_null = function()->CreateBlock("not_null");
1579 BasicBlock *is_null = function()->CreateBlock("null");
1580
1581 // Leave the object on the stack so it's there if we trap
1582 builder()->CreateCondBr(
1583 builder()->CreateICmpEQ(xstack(0)->jobject_value(), LLVMValue::null()),
1584 is_null, not_null);
1585 SharkState *saved_state = current_state()->copy();
1586
1587 // If it's not null then we need to trap
1588 builder()->SetInsertPoint(not_null);
1589 set_current_state(saved_state->copy());
1590 do_trap(
1591 Deoptimization::make_trap_request(
1592 Deoptimization::Reason_uninitialized,
1593 Deoptimization::Action_reinterpret));
1594
1595 // If it's null then we're ok
1596 builder()->SetInsertPoint(is_null);
1597 set_current_state(saved_state);
1598 if (bc() == Bytecodes::_checkcast) {
1599 push(SharkValue::create_generic(klass, pop()->jobject_value(), false));
1600 }
1601 else {
1602 pop();
1603 push(SharkValue::jint_constant(0));
1604 }
1605 }
1606
1607 void SharkTopLevelBlock::do_new() {
1608 bool will_link;
1609 ciInstanceKlass* klass = iter()->get_klass(will_link)->as_instance_klass();
1610 assert(will_link, "typeflow responsibility");
1611
1612 BasicBlock *got_tlab = NULL;
1613 BasicBlock *heap_alloc = NULL;
1614 BasicBlock *retry = NULL;
1615 BasicBlock *got_heap = NULL;
1616 BasicBlock *initialize = NULL;
1617 BasicBlock *got_fast = NULL;
1618 BasicBlock *slow_alloc_and_init = NULL;
1619 BasicBlock *got_slow = NULL;
1620 BasicBlock *push_object = NULL;
1621
1622 SharkState *fast_state = NULL;
1623
1624 Value *tlab_object = NULL;
1625 Value *heap_object = NULL;
1626 Value *fast_object = NULL;
1627 Value *slow_object = NULL;
1628 Value *object = NULL;
1629
1630 // The fast path
1631 if (!Klass::layout_helper_needs_slow_path(klass->layout_helper())) {
1632 if (UseTLAB) {
1633 got_tlab = function()->CreateBlock("got_tlab");
1634 heap_alloc = function()->CreateBlock("heap_alloc");
1635 }
1636 retry = function()->CreateBlock("retry");
1637 got_heap = function()->CreateBlock("got_heap");
1638 initialize = function()->CreateBlock("initialize");
1639 slow_alloc_and_init = function()->CreateBlock("slow_alloc_and_init");
1640 push_object = function()->CreateBlock("push_object");
1641
1642 size_t size_in_bytes = klass->size_helper() << LogHeapWordSize;
1643
1644 // Thread local allocation
1645 if (UseTLAB) {
1646 Value *top_addr = builder()->CreateAddressOfStructEntry(
1647 thread(), Thread::tlab_top_offset(),
1648 PointerType::getUnqual(SharkType::intptr_type()),
1649 "top_addr");
1650
1651 Value *end = builder()->CreateValueOfStructEntry(
1652 thread(), Thread::tlab_end_offset(),
1653 SharkType::intptr_type(),
1654 "end");
1655
1656 Value *old_top = builder()->CreateLoad(top_addr, "old_top");
1657 Value *new_top = builder()->CreateAdd(
1658 old_top, LLVMValue::intptr_constant(size_in_bytes));
1659
1660 builder()->CreateCondBr(
1661 builder()->CreateICmpULE(new_top, end),
1662 got_tlab, heap_alloc);
1663
1664 builder()->SetInsertPoint(got_tlab);
1665 tlab_object = builder()->CreateIntToPtr(
1666 old_top, SharkType::oop_type(), "tlab_object");
1667
1668 builder()->CreateStore(new_top, top_addr);
1669 builder()->CreateBr(initialize);
1670
1671 builder()->SetInsertPoint(heap_alloc);
1672 }
1673
1674 // Heap allocation
1675 Value *top_addr = builder()->CreateIntToPtr(
1676 LLVMValue::intptr_constant((intptr_t) Universe::heap()->top_addr()),
1677 PointerType::getUnqual(SharkType::intptr_type()),
1678 "top_addr");
1679
1680 Value *end = builder()->CreateLoad(
1681 builder()->CreateIntToPtr(
1682 LLVMValue::intptr_constant((intptr_t) Universe::heap()->end_addr()),
1683 PointerType::getUnqual(SharkType::intptr_type())),
1684 "end");
1685
1686 builder()->CreateBr(retry);
1687 builder()->SetInsertPoint(retry);
1688
1689 Value *old_top = builder()->CreateLoad(top_addr, "top");
1690 Value *new_top = builder()->CreateAdd(
1691 old_top, LLVMValue::intptr_constant(size_in_bytes));
1692
1693 builder()->CreateCondBr(
1694 builder()->CreateICmpULE(new_top, end),
1695 got_heap, slow_alloc_and_init);
1696
1697 builder()->SetInsertPoint(got_heap);
1698 heap_object = builder()->CreateIntToPtr(
1699 old_top, SharkType::oop_type(), "heap_object");
1700
1701 Value *check = builder()->CreateCmpxchgPtr(new_top, top_addr, old_top);
1702 builder()->CreateCondBr(
1703 builder()->CreateICmpEQ(old_top, check),
1704 initialize, retry);
1705
1706 // Initialize the object
1707 builder()->SetInsertPoint(initialize);
1708 if (tlab_object) {
1709 PHINode *phi = builder()->CreatePHI(
1710 SharkType::oop_type(), "fast_object");
1711 phi->addIncoming(tlab_object, got_tlab);
1712 phi->addIncoming(heap_object, got_heap);
1713 fast_object = phi;
1714 }
1715 else {
1716 fast_object = heap_object;
1717 }
1718
1719 builder()->CreateMemset(
1720 builder()->CreateBitCast(
1721 fast_object, PointerType::getUnqual(SharkType::jbyte_type())),
1722 LLVMValue::jbyte_constant(0),
1723 LLVMValue::jint_constant(size_in_bytes),
1724 LLVMValue::jint_constant(HeapWordSize));
1725
1726 Value *mark_addr = builder()->CreateAddressOfStructEntry(
1727 fast_object, in_ByteSize(oopDesc::mark_offset_in_bytes()),
1728 PointerType::getUnqual(SharkType::intptr_type()),
1729 "mark_addr");
1730
1731 Value *klass_addr = builder()->CreateAddressOfStructEntry(
1732 fast_object, in_ByteSize(oopDesc::klass_offset_in_bytes()),
1733 PointerType::getUnqual(SharkType::oop_type()),
1734 "klass_addr");
1735
1736 // Set the mark
1737 intptr_t mark;
1738 if (UseBiasedLocking) {
1739 Unimplemented();
1740 }
1741 else {
1742 mark = (intptr_t) markOopDesc::prototype();
1743 }
1744 builder()->CreateStore(LLVMValue::intptr_constant(mark), mark_addr);
1745
1746 // Set the class
1747 Value *rtklass = builder()->CreateInlineOop(klass);
1748 builder()->CreateStore(rtklass, klass_addr);
1749 got_fast = builder()->GetInsertBlock();
1750
1751 builder()->CreateBr(push_object);
1752 builder()->SetInsertPoint(slow_alloc_and_init);
1753 fast_state = current_state()->copy();
1754 }
1755
1756 // The slow path
1757 call_vm(
1758 builder()->new_instance(),
1759 LLVMValue::jint_constant(iter()->get_klass_index()),
1760 EX_CHECK_FULL);
1761 slow_object = get_vm_result();
1762 got_slow = builder()->GetInsertBlock();
1763
1764 // Push the object
1765 if (push_object) {
1766 builder()->CreateBr(push_object);
1767 builder()->SetInsertPoint(push_object);
1768 }
1769 if (fast_object) {
1770 PHINode *phi = builder()->CreatePHI(SharkType::oop_type(), "object");
1771 phi->addIncoming(fast_object, got_fast);
1772 phi->addIncoming(slow_object, got_slow);
1773 object = phi;
1774 current_state()->merge(fast_state, got_fast, got_slow);
1775 }
1776 else {
1777 object = slow_object;
1778 }
1779
1780 push(SharkValue::create_jobject(object, true));
1781 }
1782
1783 void SharkTopLevelBlock::do_newarray() {
1784 BasicType type = (BasicType) iter()->get_index();
1785
1786 call_vm(
1787 builder()->newarray(),
1788 LLVMValue::jint_constant(type),
1789 pop()->jint_value(),
1790 EX_CHECK_FULL);
1791
1792 ciArrayKlass *array_klass = ciArrayKlass::make(ciType::make(type));
1793 push(SharkValue::create_generic(array_klass, get_vm_result(), true));
1794 }
1795
1796 void SharkTopLevelBlock::do_anewarray() {
1797 bool will_link;
1798 ciKlass *klass = iter()->get_klass(will_link);
1799 assert(will_link, "typeflow responsibility");
1800
1801 ciObjArrayKlass *array_klass = ciObjArrayKlass::make(klass);
1802 if (!array_klass->is_loaded()) {
1803 Unimplemented();
1804 }
1805
1806 call_vm(
1807 builder()->anewarray(),
1808 LLVMValue::jint_constant(iter()->get_klass_index()),
1809 pop()->jint_value(),
1810 EX_CHECK_FULL);
1811
1812 push(SharkValue::create_generic(array_klass, get_vm_result(), true));
1813 }
1814
1815 void SharkTopLevelBlock::do_multianewarray() {
1816 bool will_link;
1817 ciArrayKlass *array_klass = iter()->get_klass(will_link)->as_array_klass();
1818 assert(will_link, "typeflow responsibility");
1819
1820 // The dimensions are stack values, so we use their slots for the
1821 // dimensions array. Note that we are storing them in the reverse
1822 // of normal stack order.
1823 int ndims = iter()->get_dimensions();
1824
1825 Value *dimensions = stack()->slot_addr(
1826 stack()->stack_slots_offset() + max_stack() - xstack_depth(),
1827 ArrayType::get(SharkType::jint_type(), ndims),
1828 "dimensions");
1829
1830 for (int i = 0; i < ndims; i++) {
1831 builder()->CreateStore(
1832 xstack(ndims - 1 - i)->jint_value(),
1833 builder()->CreateStructGEP(dimensions, i));
1834 }
1835
1836 call_vm(
1837 builder()->multianewarray(),
1838 LLVMValue::jint_constant(iter()->get_klass_index()),
1839 LLVMValue::jint_constant(ndims),
1840 builder()->CreateStructGEP(dimensions, 0),
1841 EX_CHECK_FULL);
1842
1843 // Now we can pop the dimensions off the stack
1844 for (int i = 0; i < ndims; i++)
1845 pop();
1846
1847 push(SharkValue::create_generic(array_klass, get_vm_result(), true));
1848 }
1849
1850 void SharkTopLevelBlock::acquire_method_lock() {
1851 Value *lockee;
1852 if (target()->is_static())
1853 lockee = builder()->CreateInlineOop(target()->holder()->java_mirror());
1854 else
1855 lockee = local(0)->jobject_value();
1856
1857 iter()->force_bci(start()); // for the decache in acquire_lock
1858 acquire_lock(lockee, EX_CHECK_NO_CATCH);
1859 }
1860
1861 void SharkTopLevelBlock::do_monitorenter() {
1862 SharkValue *lockee = pop();
1863 check_null(lockee);
1864 acquire_lock(lockee->jobject_value(), EX_CHECK_FULL);
1865 }
1866
1867 void SharkTopLevelBlock::do_monitorexit() {
1868 pop(); // don't need this (monitors are block structured)
1869 release_lock(EX_CHECK_NO_CATCH);
1870 }
1871
1872 void SharkTopLevelBlock::acquire_lock(Value *lockee, int exception_action) {
1873 BasicBlock *try_recursive = function()->CreateBlock("try_recursive");
1874 BasicBlock *got_recursive = function()->CreateBlock("got_recursive");
1875 BasicBlock *not_recursive = function()->CreateBlock("not_recursive");
1876 BasicBlock *acquired_fast = function()->CreateBlock("acquired_fast");
1877 BasicBlock *lock_acquired = function()->CreateBlock("lock_acquired");
1878
1879 int monitor = num_monitors();
1880 Value *monitor_addr = stack()->monitor_addr(monitor);
1881 Value *monitor_object_addr = stack()->monitor_object_addr(monitor);
1882 Value *monitor_header_addr = stack()->monitor_header_addr(monitor);
1883
1884 // Store the object and mark the slot as live
1885 builder()->CreateStore(lockee, monitor_object_addr);
1886 set_num_monitors(monitor + 1);
1887
1888 // Try a simple lock
1889 Value *mark_addr = builder()->CreateAddressOfStructEntry(
1890 lockee, in_ByteSize(oopDesc::mark_offset_in_bytes()),
1891 PointerType::getUnqual(SharkType::intptr_type()),
1892 "mark_addr");
1893
1894 Value *mark = builder()->CreateLoad(mark_addr, "mark");
1895 Value *disp = builder()->CreateOr(
1896 mark, LLVMValue::intptr_constant(markOopDesc::unlocked_value), "disp");
1897 builder()->CreateStore(disp, monitor_header_addr);
1898
1899 Value *lock = builder()->CreatePtrToInt(
1900 monitor_header_addr, SharkType::intptr_type());
1901 Value *check = builder()->CreateCmpxchgPtr(lock, mark_addr, disp);
1902 builder()->CreateCondBr(
1903 builder()->CreateICmpEQ(disp, check),
1904 acquired_fast, try_recursive);
1905
1906 // Locking failed, but maybe this thread already owns it
1907 builder()->SetInsertPoint(try_recursive);
1908 Value *addr = builder()->CreateAnd(
1909 disp,
1910 LLVMValue::intptr_constant(~markOopDesc::lock_mask_in_place));
1911
1912 // NB we use the entire stack, but JavaThread::is_lock_owned()
1913 // uses a more limited range. I don't think it hurts though...
1914 Value *stack_limit = builder()->CreateValueOfStructEntry(
1915 thread(), Thread::stack_base_offset(),
1916 SharkType::intptr_type(),
1917 "stack_limit");
1918
1919 assert(sizeof(size_t) == sizeof(intptr_t), "should be");
1920 Value *stack_size = builder()->CreateValueOfStructEntry(
1921 thread(), Thread::stack_size_offset(),
1922 SharkType::intptr_type(),
1923 "stack_size");
1924
1925 Value *stack_start =
1926 builder()->CreateSub(stack_limit, stack_size, "stack_start");
1927
1928 builder()->CreateCondBr(
1929 builder()->CreateAnd(
1930 builder()->CreateICmpUGE(addr, stack_start),
1931 builder()->CreateICmpULT(addr, stack_limit)),
1932 got_recursive, not_recursive);
1933
1934 builder()->SetInsertPoint(got_recursive);
1935 builder()->CreateStore(LLVMValue::intptr_constant(0), monitor_header_addr);
1936 builder()->CreateBr(acquired_fast);
1937
1938 // Create an edge for the state merge
1939 builder()->SetInsertPoint(acquired_fast);
1940 SharkState *fast_state = current_state()->copy();
1941 builder()->CreateBr(lock_acquired);
1942
1943 // It's not a recursive case so we need to drop into the runtime
1944 builder()->SetInsertPoint(not_recursive);
1945 call_vm(
1946 builder()->monitorenter(), monitor_addr,
1947 exception_action | EAM_MONITOR_FUDGE);
1948 BasicBlock *acquired_slow = builder()->GetInsertBlock();
1949 builder()->CreateBr(lock_acquired);
1950
1951 // All done
1952 builder()->SetInsertPoint(lock_acquired);
1953 current_state()->merge(fast_state, acquired_fast, acquired_slow);
1954 }
1955
1956 void SharkTopLevelBlock::release_lock(int exception_action) {
1957 BasicBlock *not_recursive = function()->CreateBlock("not_recursive");
1958 BasicBlock *released_fast = function()->CreateBlock("released_fast");
1959 BasicBlock *slow_path = function()->CreateBlock("slow_path");
1960 BasicBlock *lock_released = function()->CreateBlock("lock_released");
1961
1962 int monitor = num_monitors() - 1;
1963 Value *monitor_addr = stack()->monitor_addr(monitor);
1964 Value *monitor_object_addr = stack()->monitor_object_addr(monitor);
1965 Value *monitor_header_addr = stack()->monitor_header_addr(monitor);
1966
1967 // If it is recursive then we're already done
1968 Value *disp = builder()->CreateLoad(monitor_header_addr);
1969 builder()->CreateCondBr(
1970 builder()->CreateICmpEQ(disp, LLVMValue::intptr_constant(0)),
1971 released_fast, not_recursive);
1972
1973 // Try a simple unlock
1974 builder()->SetInsertPoint(not_recursive);
1975
1976 Value *lock = builder()->CreatePtrToInt(
1977 monitor_header_addr, SharkType::intptr_type());
1978
1979 Value *lockee = builder()->CreateLoad(monitor_object_addr);
1980
1981 Value *mark_addr = builder()->CreateAddressOfStructEntry(
1982 lockee, in_ByteSize(oopDesc::mark_offset_in_bytes()),
1983 PointerType::getUnqual(SharkType::intptr_type()),
1984 "mark_addr");
1985
1986 Value *check = builder()->CreateCmpxchgPtr(disp, mark_addr, lock);
1987 builder()->CreateCondBr(
1988 builder()->CreateICmpEQ(lock, check),
1989 released_fast, slow_path);
1990
1991 // Create an edge for the state merge
1992 builder()->SetInsertPoint(released_fast);
1993 SharkState *fast_state = current_state()->copy();
1994 builder()->CreateBr(lock_released);
1995
1996 // Need to drop into the runtime to release this one
1997 builder()->SetInsertPoint(slow_path);
1998 call_vm(builder()->monitorexit(), monitor_addr, exception_action);
1999 BasicBlock *released_slow = builder()->GetInsertBlock();
2000 builder()->CreateBr(lock_released);
2001
2002 // All done
2003 builder()->SetInsertPoint(lock_released);
2004 current_state()->merge(fast_state, released_fast, released_slow);
2005
2006 // The object slot is now dead
2007 set_num_monitors(monitor);
2008 }