Fri, 25 May 2012 07:53:11 -0700
7170463: C2 should recognize "obj.getClass() == A.class" code pattern
Summary: optimize this code pattern obj.getClass() == A.class.
Reviewed-by: jrose, kvn
Contributed-by: Krystal Mok <sajia@taobao.com>
1 /*
2 * Copyright (c) 1998, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #include "precompiled.hpp"
26 #include "ci/ciCPCache.hpp"
27 #include "ci/ciCallSite.hpp"
28 #include "ci/ciMethodHandle.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "compiler/compileBroker.hpp"
31 #include "compiler/compileLog.hpp"
32 #include "interpreter/linkResolver.hpp"
33 #include "opto/addnode.hpp"
34 #include "opto/callGenerator.hpp"
35 #include "opto/cfgnode.hpp"
36 #include "opto/mulnode.hpp"
37 #include "opto/parse.hpp"
38 #include "opto/rootnode.hpp"
39 #include "opto/runtime.hpp"
40 #include "opto/subnode.hpp"
41 #include "prims/nativeLookup.hpp"
42 #include "runtime/sharedRuntime.hpp"
44 #ifndef PRODUCT
45 void trace_type_profile(ciMethod *method, int depth, int bci, ciMethod *prof_method, ciKlass *prof_klass, int site_count, int receiver_count) {
46 if (TraceTypeProfile || PrintInlining || PrintOptoInlining) {
47 if (!PrintInlining) {
48 if (!PrintOpto && !PrintCompilation) {
49 method->print_short_name();
50 tty->cr();
51 }
52 CompileTask::print_inlining(prof_method, depth, bci);
53 }
54 CompileTask::print_inline_indent(depth);
55 tty->print(" \\-> TypeProfile (%d/%d counts) = ", receiver_count, site_count);
56 prof_klass->name()->print_symbol();
57 tty->cr();
58 }
59 }
60 #endif
62 CallGenerator* Compile::call_generator(ciMethod* call_method, int vtable_index, bool call_is_virtual,
63 JVMState* jvms, bool allow_inline,
64 float prof_factor, bool allow_intrinsics) {
65 ciMethod* caller = jvms->method();
66 int bci = jvms->bci();
67 Bytecodes::Code bytecode = caller->java_code_at_bci(bci);
68 guarantee(call_method != NULL, "failed method resolution");
70 // Dtrace currently doesn't work unless all calls are vanilla
71 if (env()->dtrace_method_probes()) {
72 allow_inline = false;
73 }
75 // Note: When we get profiling during stage-1 compiles, we want to pull
76 // from more specific profile data which pertains to this inlining.
77 // Right now, ignore the information in jvms->caller(), and do method[bci].
78 ciCallProfile profile = caller->call_profile_at_bci(bci);
80 // See how many times this site has been invoked.
81 int site_count = profile.count();
82 int receiver_count = -1;
83 if (call_is_virtual && UseTypeProfile && profile.has_receiver(0)) {
84 // Receivers in the profile structure are ordered by call counts
85 // so that the most called (major) receiver is profile.receiver(0).
86 receiver_count = profile.receiver_count(0);
87 }
89 CompileLog* log = this->log();
90 if (log != NULL) {
91 int rid = (receiver_count >= 0)? log->identify(profile.receiver(0)): -1;
92 int r2id = (rid != -1 && profile.has_receiver(1))? log->identify(profile.receiver(1)):-1;
93 log->begin_elem("call method='%d' count='%d' prof_factor='%g'",
94 log->identify(call_method), site_count, prof_factor);
95 if (call_is_virtual) log->print(" virtual='1'");
96 if (allow_inline) log->print(" inline='1'");
97 if (receiver_count >= 0) {
98 log->print(" receiver='%d' receiver_count='%d'", rid, receiver_count);
99 if (profile.has_receiver(1)) {
100 log->print(" receiver2='%d' receiver2_count='%d'", r2id, profile.receiver_count(1));
101 }
102 }
103 log->end_elem();
104 }
106 // Special case the handling of certain common, profitable library
107 // methods. If these methods are replaced with specialized code,
108 // then we return it as the inlined version of the call.
109 // We do this before the strict f.p. check below because the
110 // intrinsics handle strict f.p. correctly.
111 if (allow_inline && allow_intrinsics) {
112 CallGenerator* cg = find_intrinsic(call_method, call_is_virtual);
113 if (cg != NULL) return cg;
114 }
116 // Do method handle calls.
117 // NOTE: This must happen before normal inlining logic below since
118 // MethodHandle.invoke* are native methods which obviously don't
119 // have bytecodes and so normal inlining fails.
120 if (call_method->is_method_handle_invoke()) {
121 if (bytecode != Bytecodes::_invokedynamic) {
122 GraphKit kit(jvms);
123 Node* method_handle = kit.argument(0);
124 return CallGenerator::for_method_handle_call(method_handle, jvms, caller, call_method, profile);
125 }
126 else {
127 return CallGenerator::for_invokedynamic_call(jvms, caller, call_method, profile);
128 }
129 }
131 // Do not inline strict fp into non-strict code, or the reverse
132 if (caller->is_strict() ^ call_method->is_strict()) {
133 allow_inline = false;
134 }
136 // Attempt to inline...
137 if (allow_inline) {
138 // The profile data is only partly attributable to this caller,
139 // scale back the call site information.
140 float past_uses = jvms->method()->scale_count(site_count, prof_factor);
141 // This is the number of times we expect the call code to be used.
142 float expected_uses = past_uses;
144 // Try inlining a bytecoded method:
145 if (!call_is_virtual) {
146 InlineTree* ilt;
147 if (UseOldInlining) {
148 ilt = InlineTree::find_subtree_from_root(this->ilt(), jvms->caller(), jvms->method());
149 } else {
150 // Make a disembodied, stateless ILT.
151 // TO DO: When UseOldInlining is removed, copy the ILT code elsewhere.
152 float site_invoke_ratio = prof_factor;
153 // Note: ilt is for the root of this parse, not the present call site.
154 ilt = new InlineTree(this, jvms->method(), jvms->caller(), site_invoke_ratio, MaxInlineLevel);
155 }
156 WarmCallInfo scratch_ci;
157 if (!UseOldInlining)
158 scratch_ci.init(jvms, call_method, profile, prof_factor);
159 WarmCallInfo* ci = ilt->ok_to_inline(call_method, jvms, profile, &scratch_ci);
160 assert(ci != &scratch_ci, "do not let this pointer escape");
161 bool allow_inline = (ci != NULL && !ci->is_cold());
162 bool require_inline = (allow_inline && ci->is_hot());
164 if (allow_inline) {
165 CallGenerator* cg = CallGenerator::for_inline(call_method, expected_uses);
166 if (require_inline && cg != NULL && should_delay_inlining(call_method, jvms)) {
167 // Delay the inlining of this method to give us the
168 // opportunity to perform some high level optimizations
169 // first.
170 return CallGenerator::for_late_inline(call_method, cg);
171 }
172 if (cg == NULL) {
173 // Fall through.
174 } else if (require_inline || !InlineWarmCalls) {
175 return cg;
176 } else {
177 CallGenerator* cold_cg = call_generator(call_method, vtable_index, call_is_virtual, jvms, false, prof_factor);
178 return CallGenerator::for_warm_call(ci, cold_cg, cg);
179 }
180 }
181 }
183 // Try using the type profile.
184 if (call_is_virtual && site_count > 0 && receiver_count > 0) {
185 // The major receiver's count >= TypeProfileMajorReceiverPercent of site_count.
186 bool have_major_receiver = (100.*profile.receiver_prob(0) >= (float)TypeProfileMajorReceiverPercent);
187 ciMethod* receiver_method = NULL;
188 if (have_major_receiver || profile.morphism() == 1 ||
189 (profile.morphism() == 2 && UseBimorphicInlining)) {
190 // receiver_method = profile.method();
191 // Profiles do not suggest methods now. Look it up in the major receiver.
192 receiver_method = call_method->resolve_invoke(jvms->method()->holder(),
193 profile.receiver(0));
194 }
195 if (receiver_method != NULL) {
196 // The single majority receiver sufficiently outweighs the minority.
197 CallGenerator* hit_cg = this->call_generator(receiver_method,
198 vtable_index, !call_is_virtual, jvms, allow_inline, prof_factor);
199 if (hit_cg != NULL) {
200 // Look up second receiver.
201 CallGenerator* next_hit_cg = NULL;
202 ciMethod* next_receiver_method = NULL;
203 if (profile.morphism() == 2 && UseBimorphicInlining) {
204 next_receiver_method = call_method->resolve_invoke(jvms->method()->holder(),
205 profile.receiver(1));
206 if (next_receiver_method != NULL) {
207 next_hit_cg = this->call_generator(next_receiver_method,
208 vtable_index, !call_is_virtual, jvms,
209 allow_inline, prof_factor);
210 if (next_hit_cg != NULL && !next_hit_cg->is_inline() &&
211 have_major_receiver && UseOnlyInlinedBimorphic) {
212 // Skip if we can't inline second receiver's method
213 next_hit_cg = NULL;
214 }
215 }
216 }
217 CallGenerator* miss_cg;
218 Deoptimization::DeoptReason reason = (profile.morphism() == 2) ?
219 Deoptimization::Reason_bimorphic :
220 Deoptimization::Reason_class_check;
221 if (( profile.morphism() == 1 ||
222 (profile.morphism() == 2 && next_hit_cg != NULL) ) &&
223 !too_many_traps(jvms->method(), jvms->bci(), reason)
224 ) {
225 // Generate uncommon trap for class check failure path
226 // in case of monomorphic or bimorphic virtual call site.
227 miss_cg = CallGenerator::for_uncommon_trap(call_method, reason,
228 Deoptimization::Action_maybe_recompile);
229 } else {
230 // Generate virtual call for class check failure path
231 // in case of polymorphic virtual call site.
232 miss_cg = CallGenerator::for_virtual_call(call_method, vtable_index);
233 }
234 if (miss_cg != NULL) {
235 if (next_hit_cg != NULL) {
236 NOT_PRODUCT(trace_type_profile(jvms->method(), jvms->depth() - 1, jvms->bci(), next_receiver_method, profile.receiver(1), site_count, profile.receiver_count(1)));
237 // We don't need to record dependency on a receiver here and below.
238 // Whenever we inline, the dependency is added by Parse::Parse().
239 miss_cg = CallGenerator::for_predicted_call(profile.receiver(1), miss_cg, next_hit_cg, PROB_MAX);
240 }
241 if (miss_cg != NULL) {
242 NOT_PRODUCT(trace_type_profile(jvms->method(), jvms->depth() - 1, jvms->bci(), receiver_method, profile.receiver(0), site_count, receiver_count));
243 CallGenerator* cg = CallGenerator::for_predicted_call(profile.receiver(0), miss_cg, hit_cg, profile.receiver_prob(0));
244 if (cg != NULL) return cg;
245 }
246 }
247 }
248 }
249 }
250 }
252 // There was no special inlining tactic, or it bailed out.
253 // Use a more generic tactic, like a simple call.
254 if (call_is_virtual) {
255 return CallGenerator::for_virtual_call(call_method, vtable_index);
256 } else {
257 // Class Hierarchy Analysis or Type Profile reveals a unique target,
258 // or it is a static or special call.
259 return CallGenerator::for_direct_call(call_method, should_delay_inlining(call_method, jvms));
260 }
261 }
263 // Return true for methods that shouldn't be inlined early so that
264 // they are easier to analyze and optimize as intrinsics.
265 bool Compile::should_delay_inlining(ciMethod* call_method, JVMState* jvms) {
266 if (has_stringbuilder()) {
268 if ((call_method->holder() == C->env()->StringBuilder_klass() ||
269 call_method->holder() == C->env()->StringBuffer_klass()) &&
270 (jvms->method()->holder() == C->env()->StringBuilder_klass() ||
271 jvms->method()->holder() == C->env()->StringBuffer_klass())) {
272 // Delay SB calls only when called from non-SB code
273 return false;
274 }
276 switch (call_method->intrinsic_id()) {
277 case vmIntrinsics::_StringBuilder_void:
278 case vmIntrinsics::_StringBuilder_int:
279 case vmIntrinsics::_StringBuilder_String:
280 case vmIntrinsics::_StringBuilder_append_char:
281 case vmIntrinsics::_StringBuilder_append_int:
282 case vmIntrinsics::_StringBuilder_append_String:
283 case vmIntrinsics::_StringBuilder_toString:
284 case vmIntrinsics::_StringBuffer_void:
285 case vmIntrinsics::_StringBuffer_int:
286 case vmIntrinsics::_StringBuffer_String:
287 case vmIntrinsics::_StringBuffer_append_char:
288 case vmIntrinsics::_StringBuffer_append_int:
289 case vmIntrinsics::_StringBuffer_append_String:
290 case vmIntrinsics::_StringBuffer_toString:
291 case vmIntrinsics::_Integer_toString:
292 return true;
294 case vmIntrinsics::_String_String:
295 {
296 Node* receiver = jvms->map()->in(jvms->argoff() + 1);
297 if (receiver->is_Proj() && receiver->in(0)->is_CallStaticJava()) {
298 CallStaticJavaNode* csj = receiver->in(0)->as_CallStaticJava();
299 ciMethod* m = csj->method();
300 if (m != NULL &&
301 (m->intrinsic_id() == vmIntrinsics::_StringBuffer_toString ||
302 m->intrinsic_id() == vmIntrinsics::_StringBuilder_toString))
303 // Delay String.<init>(new SB())
304 return true;
305 }
306 return false;
307 }
309 default:
310 return false;
311 }
312 }
313 return false;
314 }
317 // uncommon-trap call-sites where callee is unloaded, uninitialized or will not link
318 bool Parse::can_not_compile_call_site(ciMethod *dest_method, ciInstanceKlass* klass) {
319 // Additional inputs to consider...
320 // bc = bc()
321 // caller = method()
322 // iter().get_method_holder_index()
323 assert( dest_method->is_loaded(), "ciTypeFlow should not let us get here" );
324 // Interface classes can be loaded & linked and never get around to
325 // being initialized. Uncommon-trap for not-initialized static or
326 // v-calls. Let interface calls happen.
327 ciInstanceKlass* holder_klass = dest_method->holder();
328 if (!holder_klass->is_being_initialized() &&
329 !holder_klass->is_initialized() &&
330 !holder_klass->is_interface()) {
331 uncommon_trap(Deoptimization::Reason_uninitialized,
332 Deoptimization::Action_reinterpret,
333 holder_klass);
334 return true;
335 }
337 assert(dest_method->will_link(method()->holder(), klass, bc()), "dest_method: typeflow responsibility");
338 return false;
339 }
342 //------------------------------do_call----------------------------------------
343 // Handle your basic call. Inline if we can & want to, else just setup call.
344 void Parse::do_call() {
345 // It's likely we are going to add debug info soon.
346 // Also, if we inline a guy who eventually needs debug info for this JVMS,
347 // our contribution to it is cleaned up right here.
348 kill_dead_locals();
350 // Set frequently used booleans
351 bool is_virtual = bc() == Bytecodes::_invokevirtual;
352 bool is_virtual_or_interface = is_virtual || bc() == Bytecodes::_invokeinterface;
353 bool has_receiver = is_virtual_or_interface || bc() == Bytecodes::_invokespecial;
354 bool is_invokedynamic = bc() == Bytecodes::_invokedynamic;
356 // Find target being called
357 bool will_link;
358 ciMethod* dest_method = iter().get_method(will_link);
359 ciInstanceKlass* holder_klass = dest_method->holder();
360 ciKlass* holder = iter().get_declared_method_holder();
361 ciInstanceKlass* klass = ciEnv::get_instance_klass_for_declared_method_holder(holder);
363 int nargs = dest_method->arg_size();
364 if (is_invokedynamic) nargs -= 1;
366 // uncommon-trap when callee is unloaded, uninitialized or will not link
367 // bailout when too many arguments for register representation
368 if (!will_link || can_not_compile_call_site(dest_method, klass)) {
369 #ifndef PRODUCT
370 if (PrintOpto && (Verbose || WizardMode)) {
371 method()->print_name(); tty->print_cr(" can not compile call at bci %d to:", bci());
372 dest_method->print_name(); tty->cr();
373 }
374 #endif
375 return;
376 }
377 assert(holder_klass->is_loaded(), "");
378 assert((dest_method->is_static() || is_invokedynamic) == !has_receiver , "must match bc");
379 // Note: this takes into account invokeinterface of methods declared in java/lang/Object,
380 // which should be invokevirtuals but according to the VM spec may be invokeinterfaces
381 assert(holder_klass->is_interface() || holder_klass->super() == NULL || (bc() != Bytecodes::_invokeinterface), "must match bc");
382 // Note: In the absence of miranda methods, an abstract class K can perform
383 // an invokevirtual directly on an interface method I.m if K implements I.
385 // ---------------------
386 // Does Class Hierarchy Analysis reveal only a single target of a v-call?
387 // Then we may inline or make a static call, but become dependent on there being only 1 target.
388 // Does the call-site type profile reveal only one receiver?
389 // Then we may introduce a run-time check and inline on the path where it succeeds.
390 // The other path may uncommon_trap, check for another receiver, or do a v-call.
392 // Choose call strategy.
393 bool call_is_virtual = is_virtual_or_interface;
394 int vtable_index = methodOopDesc::invalid_vtable_index;
395 ciMethod* call_method = dest_method;
397 // Try to get the most accurate receiver type
398 if (is_virtual_or_interface) {
399 Node* receiver_node = stack(sp() - nargs);
400 const TypeOopPtr* receiver_type = _gvn.type(receiver_node)->isa_oopptr();
401 ciMethod* optimized_virtual_method = optimize_inlining(method(), bci(), klass, dest_method, receiver_type);
403 // Have the call been sufficiently improved such that it is no longer a virtual?
404 if (optimized_virtual_method != NULL) {
405 call_method = optimized_virtual_method;
406 call_is_virtual = false;
407 } else if (!UseInlineCaches && is_virtual && call_method->is_loaded()) {
408 // We can make a vtable call at this site
409 vtable_index = call_method->resolve_vtable_index(method()->holder(), klass);
410 }
411 }
413 // Note: It's OK to try to inline a virtual call.
414 // The call generator will not attempt to inline a polymorphic call
415 // unless it knows how to optimize the receiver dispatch.
416 bool try_inline = (C->do_inlining() || InlineAccessors);
418 // ---------------------
419 inc_sp(- nargs); // Temporarily pop args for JVM state of call
420 JVMState* jvms = sync_jvms();
422 // ---------------------
423 // Decide call tactic.
424 // This call checks with CHA, the interpreter profile, intrinsics table, etc.
425 // It decides whether inlining is desirable or not.
426 CallGenerator* cg = C->call_generator(call_method, vtable_index, call_is_virtual, jvms, try_inline, prof_factor());
428 // ---------------------
429 // Round double arguments before call
430 round_double_arguments(dest_method);
432 #ifndef PRODUCT
433 // bump global counters for calls
434 count_compiled_calls(false/*at_method_entry*/, cg->is_inline());
436 // Record first part of parsing work for this call
437 parse_histogram()->record_change();
438 #endif // not PRODUCT
440 assert(jvms == this->jvms(), "still operating on the right JVMS");
441 assert(jvms_in_sync(), "jvms must carry full info into CG");
443 // save across call, for a subsequent cast_not_null.
444 Node* receiver = has_receiver ? argument(0) : NULL;
446 // Bump method data counters (We profile *before* the call is made
447 // because exceptions don't return to the call site.)
448 profile_call(receiver);
450 JVMState* new_jvms;
451 if ((new_jvms = cg->generate(jvms)) == NULL) {
452 // When inlining attempt fails (e.g., too many arguments),
453 // it may contaminate the current compile state, making it
454 // impossible to pull back and try again. Once we call
455 // cg->generate(), we are committed. If it fails, the whole
456 // compilation task is compromised.
457 if (failing()) return;
459 // This can happen if a library intrinsic is available, but refuses
460 // the call site, perhaps because it did not match a pattern the
461 // intrinsic was expecting to optimize. Should always be possible to
462 // get a normal java call that may inline in that case
463 cg = C->call_generator(call_method, vtable_index, call_is_virtual, jvms, try_inline, prof_factor(), /* allow_intrinsics= */ false);
464 if ((new_jvms = cg->generate(jvms)) == NULL) {
465 guarantee(failing(), "call failed to generate: calls should work");
466 return;
467 }
468 }
470 if (cg->is_inline()) {
471 // Accumulate has_loops estimate
472 C->set_has_loops(C->has_loops() || call_method->has_loops());
473 C->env()->notice_inlined_method(call_method);
474 }
476 // Reset parser state from [new_]jvms, which now carries results of the call.
477 // Return value (if any) is already pushed on the stack by the cg.
478 add_exception_states_from(new_jvms);
479 if (new_jvms->map()->control() == top()) {
480 stop_and_kill_map();
481 } else {
482 assert(new_jvms->same_calls_as(jvms), "method/bci left unchanged");
483 set_jvms(new_jvms);
484 }
486 if (!stopped()) {
487 // This was some sort of virtual call, which did a null check for us.
488 // Now we can assert receiver-not-null, on the normal return path.
489 if (receiver != NULL && cg->is_virtual()) {
490 Node* cast = cast_not_null(receiver);
491 // %%% assert(receiver == cast, "should already have cast the receiver");
492 }
494 // Round double result after a call from strict to non-strict code
495 round_double_result(dest_method);
497 // If the return type of the method is not loaded, assert that the
498 // value we got is a null. Otherwise, we need to recompile.
499 if (!dest_method->return_type()->is_loaded()) {
500 #ifndef PRODUCT
501 if (PrintOpto && (Verbose || WizardMode)) {
502 method()->print_name(); tty->print_cr(" asserting nullness of result at bci: %d", bci());
503 dest_method->print_name(); tty->cr();
504 }
505 #endif
506 if (C->log() != NULL) {
507 C->log()->elem("assert_null reason='return' klass='%d'",
508 C->log()->identify(dest_method->return_type()));
509 }
510 // If there is going to be a trap, put it at the next bytecode:
511 set_bci(iter().next_bci());
512 do_null_assert(peek(), T_OBJECT);
513 set_bci(iter().cur_bci()); // put it back
514 }
515 }
517 // Restart record of parsing work after possible inlining of call
518 #ifndef PRODUCT
519 parse_histogram()->set_initial_state(bc());
520 #endif
521 }
523 //---------------------------catch_call_exceptions-----------------------------
524 // Put a Catch and CatchProj nodes behind a just-created call.
525 // Send their caught exceptions to the proper handler.
526 // This may be used after a call to the rethrow VM stub,
527 // when it is needed to process unloaded exception classes.
528 void Parse::catch_call_exceptions(ciExceptionHandlerStream& handlers) {
529 // Exceptions are delivered through this channel:
530 Node* i_o = this->i_o();
532 // Add a CatchNode.
533 GrowableArray<int>* bcis = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, -1);
534 GrowableArray<const Type*>* extypes = new (C->node_arena()) GrowableArray<const Type*>(C->node_arena(), 8, 0, NULL);
535 GrowableArray<int>* saw_unloaded = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, 0);
537 for (; !handlers.is_done(); handlers.next()) {
538 ciExceptionHandler* h = handlers.handler();
539 int h_bci = h->handler_bci();
540 ciInstanceKlass* h_klass = h->is_catch_all() ? env()->Throwable_klass() : h->catch_klass();
541 // Do not introduce unloaded exception types into the graph:
542 if (!h_klass->is_loaded()) {
543 if (saw_unloaded->contains(h_bci)) {
544 /* We've already seen an unloaded exception with h_bci,
545 so don't duplicate. Duplication will cause the CatchNode to be
546 unnecessarily large. See 4713716. */
547 continue;
548 } else {
549 saw_unloaded->append(h_bci);
550 }
551 }
552 const Type* h_extype = TypeOopPtr::make_from_klass(h_klass);
553 // (We use make_from_klass because it respects UseUniqueSubclasses.)
554 h_extype = h_extype->join(TypeInstPtr::NOTNULL);
555 assert(!h_extype->empty(), "sanity");
556 // Note: It's OK if the BCIs repeat themselves.
557 bcis->append(h_bci);
558 extypes->append(h_extype);
559 }
561 int len = bcis->length();
562 CatchNode *cn = new (C, 2) CatchNode(control(), i_o, len+1);
563 Node *catch_ = _gvn.transform(cn);
565 // now branch with the exception state to each of the (potential)
566 // handlers
567 for(int i=0; i < len; i++) {
568 // Setup JVM state to enter the handler.
569 PreserveJVMState pjvms(this);
570 // Locals are just copied from before the call.
571 // Get control from the CatchNode.
572 int handler_bci = bcis->at(i);
573 Node* ctrl = _gvn.transform( new (C, 1) CatchProjNode(catch_, i+1,handler_bci));
574 // This handler cannot happen?
575 if (ctrl == top()) continue;
576 set_control(ctrl);
578 // Create exception oop
579 const TypeInstPtr* extype = extypes->at(i)->is_instptr();
580 Node *ex_oop = _gvn.transform(new (C, 2) CreateExNode(extypes->at(i), ctrl, i_o));
582 // Handle unloaded exception classes.
583 if (saw_unloaded->contains(handler_bci)) {
584 // An unloaded exception type is coming here. Do an uncommon trap.
585 #ifndef PRODUCT
586 // We do not expect the same handler bci to take both cold unloaded
587 // and hot loaded exceptions. But, watch for it.
588 if (extype->is_loaded()) {
589 tty->print_cr("Warning: Handler @%d takes mixed loaded/unloaded exceptions in ");
590 method()->print_name(); tty->cr();
591 } else if (PrintOpto && (Verbose || WizardMode)) {
592 tty->print("Bailing out on unloaded exception type ");
593 extype->klass()->print_name();
594 tty->print(" at bci:%d in ", bci());
595 method()->print_name(); tty->cr();
596 }
597 #endif
598 // Emit an uncommon trap instead of processing the block.
599 set_bci(handler_bci);
600 push_ex_oop(ex_oop);
601 uncommon_trap(Deoptimization::Reason_unloaded,
602 Deoptimization::Action_reinterpret,
603 extype->klass(), "!loaded exception");
604 set_bci(iter().cur_bci()); // put it back
605 continue;
606 }
608 // go to the exception handler
609 if (handler_bci < 0) { // merge with corresponding rethrow node
610 throw_to_exit(make_exception_state(ex_oop));
611 } else { // Else jump to corresponding handle
612 push_ex_oop(ex_oop); // Clear stack and push just the oop.
613 merge_exception(handler_bci);
614 }
615 }
617 // The first CatchProj is for the normal return.
618 // (Note: If this is a call to rethrow_Java, this node goes dead.)
619 set_control(_gvn.transform( new (C, 1) CatchProjNode(catch_, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci)));
620 }
623 //----------------------------catch_inline_exceptions--------------------------
624 // Handle all exceptions thrown by an inlined method or individual bytecode.
625 // Common case 1: we have no handler, so all exceptions merge right into
626 // the rethrow case.
627 // Case 2: we have some handlers, with loaded exception klasses that have
628 // no subklasses. We do a Deutsch-Shiffman style type-check on the incoming
629 // exception oop and branch to the handler directly.
630 // Case 3: We have some handlers with subklasses or are not loaded at
631 // compile-time. We have to call the runtime to resolve the exception.
632 // So we insert a RethrowCall and all the logic that goes with it.
633 void Parse::catch_inline_exceptions(SafePointNode* ex_map) {
634 // Caller is responsible for saving away the map for normal control flow!
635 assert(stopped(), "call set_map(NULL) first");
636 assert(method()->has_exception_handlers(), "don't come here w/o work to do");
638 Node* ex_node = saved_ex_oop(ex_map);
639 if (ex_node == top()) {
640 // No action needed.
641 return;
642 }
643 const TypeInstPtr* ex_type = _gvn.type(ex_node)->isa_instptr();
644 NOT_PRODUCT(if (ex_type==NULL) tty->print_cr("*** Exception not InstPtr"));
645 if (ex_type == NULL)
646 ex_type = TypeOopPtr::make_from_klass(env()->Throwable_klass())->is_instptr();
648 // determine potential exception handlers
649 ciExceptionHandlerStream handlers(method(), bci(),
650 ex_type->klass()->as_instance_klass(),
651 ex_type->klass_is_exact());
653 // Start executing from the given throw state. (Keep its stack, for now.)
654 // Get the exception oop as known at compile time.
655 ex_node = use_exception_state(ex_map);
657 // Get the exception oop klass from its header
658 Node* ex_klass_node = NULL;
659 if (has_ex_handler() && !ex_type->klass_is_exact()) {
660 Node* p = basic_plus_adr( ex_node, ex_node, oopDesc::klass_offset_in_bytes());
661 ex_klass_node = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT) );
663 // Compute the exception klass a little more cleverly.
664 // Obvious solution is to simple do a LoadKlass from the 'ex_node'.
665 // However, if the ex_node is a PhiNode, I'm going to do a LoadKlass for
666 // each arm of the Phi. If I know something clever about the exceptions
667 // I'm loading the class from, I can replace the LoadKlass with the
668 // klass constant for the exception oop.
669 if( ex_node->is_Phi() ) {
670 ex_klass_node = new (C, ex_node->req()) PhiNode( ex_node->in(0), TypeKlassPtr::OBJECT );
671 for( uint i = 1; i < ex_node->req(); i++ ) {
672 Node* p = basic_plus_adr( ex_node->in(i), ex_node->in(i), oopDesc::klass_offset_in_bytes() );
673 Node* k = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT) );
674 ex_klass_node->init_req( i, k );
675 }
676 _gvn.set_type(ex_klass_node, TypeKlassPtr::OBJECT);
678 }
679 }
681 // Scan the exception table for applicable handlers.
682 // If none, we can call rethrow() and be done!
683 // If precise (loaded with no subklasses), insert a D.S. style
684 // pointer compare to the correct handler and loop back.
685 // If imprecise, switch to the Rethrow VM-call style handling.
687 int remaining = handlers.count_remaining();
689 // iterate through all entries sequentially
690 for (;!handlers.is_done(); handlers.next()) {
691 ciExceptionHandler* handler = handlers.handler();
693 if (handler->is_rethrow()) {
694 // If we fell off the end of the table without finding an imprecise
695 // exception klass (and without finding a generic handler) then we
696 // know this exception is not handled in this method. We just rethrow
697 // the exception into the caller.
698 throw_to_exit(make_exception_state(ex_node));
699 return;
700 }
702 // exception handler bci range covers throw_bci => investigate further
703 int handler_bci = handler->handler_bci();
705 if (remaining == 1) {
706 push_ex_oop(ex_node); // Push exception oop for handler
707 #ifndef PRODUCT
708 if (PrintOpto && WizardMode) {
709 tty->print_cr(" Catching every inline exception bci:%d -> handler_bci:%d", bci(), handler_bci);
710 }
711 #endif
712 merge_exception(handler_bci); // jump to handler
713 return; // No more handling to be done here!
714 }
716 // Get the handler's klass
717 ciInstanceKlass* klass = handler->catch_klass();
719 if (!klass->is_loaded()) { // klass is not loaded?
720 // fall through into catch_call_exceptions which will emit a
721 // handler with an uncommon trap.
722 break;
723 }
725 if (klass->is_interface()) // should not happen, but...
726 break; // bail out
728 // Check the type of the exception against the catch type
729 const TypeKlassPtr *tk = TypeKlassPtr::make(klass);
730 Node* con = _gvn.makecon(tk);
731 Node* not_subtype_ctrl = gen_subtype_check(ex_klass_node, con);
732 if (!stopped()) {
733 PreserveJVMState pjvms(this);
734 const TypeInstPtr* tinst = TypeOopPtr::make_from_klass_unique(klass)->cast_to_ptr_type(TypePtr::NotNull)->is_instptr();
735 assert(klass->has_subklass() || tinst->klass_is_exact(), "lost exactness");
736 Node* ex_oop = _gvn.transform(new (C, 2) CheckCastPPNode(control(), ex_node, tinst));
737 push_ex_oop(ex_oop); // Push exception oop for handler
738 #ifndef PRODUCT
739 if (PrintOpto && WizardMode) {
740 tty->print(" Catching inline exception bci:%d -> handler_bci:%d -- ", bci(), handler_bci);
741 klass->print_name();
742 tty->cr();
743 }
744 #endif
745 merge_exception(handler_bci);
746 }
747 set_control(not_subtype_ctrl);
749 // Come here if exception does not match handler.
750 // Carry on with more handler checks.
751 --remaining;
752 }
754 assert(!stopped(), "you should return if you finish the chain");
756 // Oops, need to call into the VM to resolve the klasses at runtime.
757 // Note: This call must not deoptimize, since it is not a real at this bci!
758 kill_dead_locals();
760 make_runtime_call(RC_NO_LEAF | RC_MUST_THROW,
761 OptoRuntime::rethrow_Type(),
762 OptoRuntime::rethrow_stub(),
763 NULL, NULL,
764 ex_node);
766 // Rethrow is a pure call, no side effects, only a result.
767 // The result cannot be allocated, so we use I_O
769 // Catch exceptions from the rethrow
770 catch_call_exceptions(handlers);
771 }
774 // (Note: Moved add_debug_info into GraphKit::add_safepoint_edges.)
777 #ifndef PRODUCT
778 void Parse::count_compiled_calls(bool at_method_entry, bool is_inline) {
779 if( CountCompiledCalls ) {
780 if( at_method_entry ) {
781 // bump invocation counter if top method (for statistics)
782 if (CountCompiledCalls && depth() == 1) {
783 const TypeOopPtr* addr_type = TypeOopPtr::make_from_constant(method());
784 Node* adr1 = makecon(addr_type);
785 Node* adr2 = basic_plus_adr(adr1, adr1, in_bytes(methodOopDesc::compiled_invocation_counter_offset()));
786 increment_counter(adr2);
787 }
788 } else if (is_inline) {
789 switch (bc()) {
790 case Bytecodes::_invokevirtual: increment_counter(SharedRuntime::nof_inlined_calls_addr()); break;
791 case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_inlined_interface_calls_addr()); break;
792 case Bytecodes::_invokestatic:
793 case Bytecodes::_invokedynamic:
794 case Bytecodes::_invokespecial: increment_counter(SharedRuntime::nof_inlined_static_calls_addr()); break;
795 default: fatal("unexpected call bytecode");
796 }
797 } else {
798 switch (bc()) {
799 case Bytecodes::_invokevirtual: increment_counter(SharedRuntime::nof_normal_calls_addr()); break;
800 case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_interface_calls_addr()); break;
801 case Bytecodes::_invokestatic:
802 case Bytecodes::_invokedynamic:
803 case Bytecodes::_invokespecial: increment_counter(SharedRuntime::nof_static_calls_addr()); break;
804 default: fatal("unexpected call bytecode");
805 }
806 }
807 }
808 }
809 #endif //PRODUCT
812 // Identify possible target method and inlining style
813 ciMethod* Parse::optimize_inlining(ciMethod* caller, int bci, ciInstanceKlass* klass,
814 ciMethod *dest_method, const TypeOopPtr* receiver_type) {
815 // only use for virtual or interface calls
817 // If it is obviously final, do not bother to call find_monomorphic_target,
818 // because the class hierarchy checks are not needed, and may fail due to
819 // incompletely loaded classes. Since we do our own class loading checks
820 // in this module, we may confidently bind to any method.
821 if (dest_method->can_be_statically_bound()) {
822 return dest_method;
823 }
825 // Attempt to improve the receiver
826 bool actual_receiver_is_exact = false;
827 ciInstanceKlass* actual_receiver = klass;
828 if (receiver_type != NULL) {
829 // Array methods are all inherited from Object, and are monomorphic.
830 if (receiver_type->isa_aryptr() &&
831 dest_method->holder() == env()->Object_klass()) {
832 return dest_method;
833 }
835 // All other interesting cases are instance klasses.
836 if (!receiver_type->isa_instptr()) {
837 return NULL;
838 }
840 ciInstanceKlass *ikl = receiver_type->klass()->as_instance_klass();
841 if (ikl->is_loaded() && ikl->is_initialized() && !ikl->is_interface() &&
842 (ikl == actual_receiver || ikl->is_subtype_of(actual_receiver))) {
843 // ikl is a same or better type than the original actual_receiver,
844 // e.g. static receiver from bytecodes.
845 actual_receiver = ikl;
846 // Is the actual_receiver exact?
847 actual_receiver_is_exact = receiver_type->klass_is_exact();
848 }
849 }
851 ciInstanceKlass* calling_klass = caller->holder();
852 ciMethod* cha_monomorphic_target = dest_method->find_monomorphic_target(calling_klass, klass, actual_receiver);
853 if (cha_monomorphic_target != NULL) {
854 assert(!cha_monomorphic_target->is_abstract(), "");
855 // Look at the method-receiver type. Does it add "too much information"?
856 ciKlass* mr_klass = cha_monomorphic_target->holder();
857 const Type* mr_type = TypeInstPtr::make(TypePtr::BotPTR, mr_klass);
858 if (receiver_type == NULL || !receiver_type->higher_equal(mr_type)) {
859 // Calling this method would include an implicit cast to its holder.
860 // %%% Not yet implemented. Would throw minor asserts at present.
861 // %%% The most common wins are already gained by +UseUniqueSubclasses.
862 // To fix, put the higher_equal check at the call of this routine,
863 // and add a CheckCastPP to the receiver.
864 if (TraceDependencies) {
865 tty->print_cr("found unique CHA method, but could not cast up");
866 tty->print(" method = ");
867 cha_monomorphic_target->print();
868 tty->cr();
869 }
870 if (C->log() != NULL) {
871 C->log()->elem("missed_CHA_opportunity klass='%d' method='%d'",
872 C->log()->identify(klass),
873 C->log()->identify(cha_monomorphic_target));
874 }
875 cha_monomorphic_target = NULL;
876 }
877 }
878 if (cha_monomorphic_target != NULL) {
879 // Hardwiring a virtual.
880 // If we inlined because CHA revealed only a single target method,
881 // then we are dependent on that target method not getting overridden
882 // by dynamic class loading. Be sure to test the "static" receiver
883 // dest_method here, as opposed to the actual receiver, which may
884 // falsely lead us to believe that the receiver is final or private.
885 C->dependencies()->assert_unique_concrete_method(actual_receiver, cha_monomorphic_target);
886 return cha_monomorphic_target;
887 }
889 // If the type is exact, we can still bind the method w/o a vcall.
890 // (This case comes after CHA so we can see how much extra work it does.)
891 if (actual_receiver_is_exact) {
892 // In case of evolution, there is a dependence on every inlined method, since each
893 // such method can be changed when its class is redefined.
894 ciMethod* exact_method = dest_method->resolve_invoke(calling_klass, actual_receiver);
895 if (exact_method != NULL) {
896 #ifndef PRODUCT
897 if (PrintOpto) {
898 tty->print(" Calling method via exact type @%d --- ", bci);
899 exact_method->print_name();
900 tty->cr();
901 }
902 #endif
903 return exact_method;
904 }
905 }
907 return NULL;
908 }