Sat, 16 Mar 2013 07:39:14 -0700
8009166: [parfait] Null pointer deference in hotspot/src/share/vm/opto/type.cpp
Summary: add guarantee() to as_instance_type()
Reviewed-by: kvn, twisti
1 /*
2 * Copyright (c) 1998, 2012, 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.
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23 */
25 #include "precompiled.hpp"
26 #include "ci/ciCallSite.hpp"
27 #include "ci/ciMethodHandle.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "compiler/compileBroker.hpp"
30 #include "compiler/compileLog.hpp"
31 #include "interpreter/linkResolver.hpp"
32 #include "opto/addnode.hpp"
33 #include "opto/callGenerator.hpp"
34 #include "opto/cfgnode.hpp"
35 #include "opto/mulnode.hpp"
36 #include "opto/parse.hpp"
37 #include "opto/rootnode.hpp"
38 #include "opto/runtime.hpp"
39 #include "opto/subnode.hpp"
40 #include "prims/nativeLookup.hpp"
41 #include "runtime/sharedRuntime.hpp"
43 void trace_type_profile(Compile* C, ciMethod *method, int depth, int bci, ciMethod *prof_method, ciKlass *prof_klass, int site_count, int receiver_count) {
44 if (TraceTypeProfile || PrintInlining NOT_PRODUCT(|| PrintOptoInlining)) {
45 outputStream* out = tty;
46 if (!PrintInlining) {
47 if (NOT_PRODUCT(!PrintOpto &&) !PrintCompilation) {
48 method->print_short_name();
49 tty->cr();
50 }
51 CompileTask::print_inlining(prof_method, depth, bci);
52 } else {
53 out = C->print_inlining_stream();
54 }
55 CompileTask::print_inline_indent(depth, out);
56 out->print(" \\-> TypeProfile (%d/%d counts) = ", receiver_count, site_count);
57 stringStream ss;
58 prof_klass->name()->print_symbol_on(&ss);
59 out->print(ss.as_string());
60 out->cr();
61 }
62 }
64 CallGenerator* Compile::call_generator(ciMethod* callee, int vtable_index, bool call_does_dispatch,
65 JVMState* jvms, bool allow_inline,
66 float prof_factor, bool allow_intrinsics, bool delayed_forbidden) {
67 ciMethod* caller = jvms->method();
68 int bci = jvms->bci();
69 Bytecodes::Code bytecode = caller->java_code_at_bci(bci);
70 guarantee(callee != NULL, "failed method resolution");
72 // Dtrace currently doesn't work unless all calls are vanilla
73 if (env()->dtrace_method_probes()) {
74 allow_inline = false;
75 }
77 // Note: When we get profiling during stage-1 compiles, we want to pull
78 // from more specific profile data which pertains to this inlining.
79 // Right now, ignore the information in jvms->caller(), and do method[bci].
80 ciCallProfile profile = caller->call_profile_at_bci(bci);
82 // See how many times this site has been invoked.
83 int site_count = profile.count();
84 int receiver_count = -1;
85 if (call_does_dispatch && UseTypeProfile && profile.has_receiver(0)) {
86 // Receivers in the profile structure are ordered by call counts
87 // so that the most called (major) receiver is profile.receiver(0).
88 receiver_count = profile.receiver_count(0);
89 }
91 CompileLog* log = this->log();
92 if (log != NULL) {
93 int rid = (receiver_count >= 0)? log->identify(profile.receiver(0)): -1;
94 int r2id = (rid != -1 && profile.has_receiver(1))? log->identify(profile.receiver(1)):-1;
95 log->begin_elem("call method='%d' count='%d' prof_factor='%g'",
96 log->identify(callee), site_count, prof_factor);
97 if (call_does_dispatch) log->print(" virtual='1'");
98 if (allow_inline) log->print(" inline='1'");
99 if (receiver_count >= 0) {
100 log->print(" receiver='%d' receiver_count='%d'", rid, receiver_count);
101 if (profile.has_receiver(1)) {
102 log->print(" receiver2='%d' receiver2_count='%d'", r2id, profile.receiver_count(1));
103 }
104 }
105 log->end_elem();
106 }
108 // Special case the handling of certain common, profitable library
109 // methods. If these methods are replaced with specialized code,
110 // then we return it as the inlined version of the call.
111 // We do this before the strict f.p. check below because the
112 // intrinsics handle strict f.p. correctly.
113 if (allow_inline && allow_intrinsics) {
114 CallGenerator* cg = find_intrinsic(callee, call_does_dispatch);
115 if (cg != NULL) {
116 if (cg->is_predicted()) {
117 // Code without intrinsic but, hopefully, inlined.
118 CallGenerator* inline_cg = this->call_generator(callee,
119 vtable_index, call_does_dispatch, jvms, allow_inline, prof_factor, false);
120 if (inline_cg != NULL) {
121 cg = CallGenerator::for_predicted_intrinsic(cg, inline_cg);
122 }
123 }
124 return cg;
125 }
126 }
128 // Do method handle calls.
129 // NOTE: This must happen before normal inlining logic below since
130 // MethodHandle.invoke* are native methods which obviously don't
131 // have bytecodes and so normal inlining fails.
132 if (callee->is_method_handle_intrinsic()) {
133 CallGenerator* cg = CallGenerator::for_method_handle_call(jvms, caller, callee, delayed_forbidden);
134 assert(cg == NULL || !delayed_forbidden || !cg->is_late_inline() || cg->is_mh_late_inline(), "unexpected CallGenerator");
135 return cg;
136 }
138 // Do not inline strict fp into non-strict code, or the reverse
139 if (caller->is_strict() ^ callee->is_strict()) {
140 allow_inline = false;
141 }
143 // Attempt to inline...
144 if (allow_inline) {
145 // The profile data is only partly attributable to this caller,
146 // scale back the call site information.
147 float past_uses = jvms->method()->scale_count(site_count, prof_factor);
148 // This is the number of times we expect the call code to be used.
149 float expected_uses = past_uses;
151 // Try inlining a bytecoded method:
152 if (!call_does_dispatch) {
153 InlineTree* ilt;
154 if (UseOldInlining) {
155 ilt = InlineTree::find_subtree_from_root(this->ilt(), jvms->caller(), jvms->method());
156 } else {
157 // Make a disembodied, stateless ILT.
158 // TO DO: When UseOldInlining is removed, copy the ILT code elsewhere.
159 float site_invoke_ratio = prof_factor;
160 // Note: ilt is for the root of this parse, not the present call site.
161 ilt = new InlineTree(this, jvms->method(), jvms->caller(), site_invoke_ratio, MaxInlineLevel);
162 }
163 WarmCallInfo scratch_ci;
164 if (!UseOldInlining)
165 scratch_ci.init(jvms, callee, profile, prof_factor);
166 bool should_delay = false;
167 WarmCallInfo* ci = ilt->ok_to_inline(callee, jvms, profile, &scratch_ci, should_delay);
168 assert(ci != &scratch_ci, "do not let this pointer escape");
169 bool allow_inline = (ci != NULL && !ci->is_cold());
170 bool require_inline = (allow_inline && ci->is_hot());
172 if (allow_inline) {
173 CallGenerator* cg = CallGenerator::for_inline(callee, expected_uses);
175 if (require_inline && cg != NULL) {
176 // Delay the inlining of this method to give us the
177 // opportunity to perform some high level optimizations
178 // first.
179 if (should_delay_inlining(callee, jvms)) {
180 assert(!delayed_forbidden, "strange");
181 return CallGenerator::for_string_late_inline(callee, cg);
182 } else if ((should_delay || AlwaysIncrementalInline) && !delayed_forbidden) {
183 return CallGenerator::for_late_inline(callee, cg);
184 }
185 }
186 if (cg == NULL || should_delay) {
187 // Fall through.
188 } else if (require_inline || !InlineWarmCalls) {
189 return cg;
190 } else {
191 CallGenerator* cold_cg = call_generator(callee, vtable_index, call_does_dispatch, jvms, false, prof_factor);
192 return CallGenerator::for_warm_call(ci, cold_cg, cg);
193 }
194 }
195 }
197 // Try using the type profile.
198 if (call_does_dispatch && site_count > 0 && receiver_count > 0) {
199 // The major receiver's count >= TypeProfileMajorReceiverPercent of site_count.
200 bool have_major_receiver = (100.*profile.receiver_prob(0) >= (float)TypeProfileMajorReceiverPercent);
201 ciMethod* receiver_method = NULL;
202 if (have_major_receiver || profile.morphism() == 1 ||
203 (profile.morphism() == 2 && UseBimorphicInlining)) {
204 // receiver_method = profile.method();
205 // Profiles do not suggest methods now. Look it up in the major receiver.
206 receiver_method = callee->resolve_invoke(jvms->method()->holder(),
207 profile.receiver(0));
208 }
209 if (receiver_method != NULL) {
210 // The single majority receiver sufficiently outweighs the minority.
211 CallGenerator* hit_cg = this->call_generator(receiver_method,
212 vtable_index, !call_does_dispatch, jvms, allow_inline, prof_factor);
213 if (hit_cg != NULL) {
214 // Look up second receiver.
215 CallGenerator* next_hit_cg = NULL;
216 ciMethod* next_receiver_method = NULL;
217 if (profile.morphism() == 2 && UseBimorphicInlining) {
218 next_receiver_method = callee->resolve_invoke(jvms->method()->holder(),
219 profile.receiver(1));
220 if (next_receiver_method != NULL) {
221 next_hit_cg = this->call_generator(next_receiver_method,
222 vtable_index, !call_does_dispatch, jvms,
223 allow_inline, prof_factor);
224 if (next_hit_cg != NULL && !next_hit_cg->is_inline() &&
225 have_major_receiver && UseOnlyInlinedBimorphic) {
226 // Skip if we can't inline second receiver's method
227 next_hit_cg = NULL;
228 }
229 }
230 }
231 CallGenerator* miss_cg;
232 Deoptimization::DeoptReason reason = (profile.morphism() == 2) ?
233 Deoptimization::Reason_bimorphic :
234 Deoptimization::Reason_class_check;
235 if (( profile.morphism() == 1 ||
236 (profile.morphism() == 2 && next_hit_cg != NULL) ) &&
237 !too_many_traps(jvms->method(), jvms->bci(), reason)
238 ) {
239 // Generate uncommon trap for class check failure path
240 // in case of monomorphic or bimorphic virtual call site.
241 miss_cg = CallGenerator::for_uncommon_trap(callee, reason,
242 Deoptimization::Action_maybe_recompile);
243 } else {
244 // Generate virtual call for class check failure path
245 // in case of polymorphic virtual call site.
246 miss_cg = CallGenerator::for_virtual_call(callee, vtable_index);
247 }
248 if (miss_cg != NULL) {
249 if (next_hit_cg != NULL) {
250 trace_type_profile(C, jvms->method(), jvms->depth() - 1, jvms->bci(), next_receiver_method, profile.receiver(1), site_count, profile.receiver_count(1));
251 // We don't need to record dependency on a receiver here and below.
252 // Whenever we inline, the dependency is added by Parse::Parse().
253 miss_cg = CallGenerator::for_predicted_call(profile.receiver(1), miss_cg, next_hit_cg, PROB_MAX);
254 }
255 if (miss_cg != NULL) {
256 trace_type_profile(C, jvms->method(), jvms->depth() - 1, jvms->bci(), receiver_method, profile.receiver(0), site_count, receiver_count);
257 CallGenerator* cg = CallGenerator::for_predicted_call(profile.receiver(0), miss_cg, hit_cg, profile.receiver_prob(0));
258 if (cg != NULL) return cg;
259 }
260 }
261 }
262 }
263 }
264 }
266 // There was no special inlining tactic, or it bailed out.
267 // Use a more generic tactic, like a simple call.
268 if (call_does_dispatch) {
269 return CallGenerator::for_virtual_call(callee, vtable_index);
270 } else {
271 // Class Hierarchy Analysis or Type Profile reveals a unique target,
272 // or it is a static or special call.
273 return CallGenerator::for_direct_call(callee, should_delay_inlining(callee, jvms));
274 }
275 }
277 // Return true for methods that shouldn't be inlined early so that
278 // they are easier to analyze and optimize as intrinsics.
279 bool Compile::should_delay_inlining(ciMethod* call_method, JVMState* jvms) {
280 if (has_stringbuilder()) {
282 if ((call_method->holder() == C->env()->StringBuilder_klass() ||
283 call_method->holder() == C->env()->StringBuffer_klass()) &&
284 (jvms->method()->holder() == C->env()->StringBuilder_klass() ||
285 jvms->method()->holder() == C->env()->StringBuffer_klass())) {
286 // Delay SB calls only when called from non-SB code
287 return false;
288 }
290 switch (call_method->intrinsic_id()) {
291 case vmIntrinsics::_StringBuilder_void:
292 case vmIntrinsics::_StringBuilder_int:
293 case vmIntrinsics::_StringBuilder_String:
294 case vmIntrinsics::_StringBuilder_append_char:
295 case vmIntrinsics::_StringBuilder_append_int:
296 case vmIntrinsics::_StringBuilder_append_String:
297 case vmIntrinsics::_StringBuilder_toString:
298 case vmIntrinsics::_StringBuffer_void:
299 case vmIntrinsics::_StringBuffer_int:
300 case vmIntrinsics::_StringBuffer_String:
301 case vmIntrinsics::_StringBuffer_append_char:
302 case vmIntrinsics::_StringBuffer_append_int:
303 case vmIntrinsics::_StringBuffer_append_String:
304 case vmIntrinsics::_StringBuffer_toString:
305 case vmIntrinsics::_Integer_toString:
306 return true;
308 case vmIntrinsics::_String_String:
309 {
310 Node* receiver = jvms->map()->in(jvms->argoff() + 1);
311 if (receiver->is_Proj() && receiver->in(0)->is_CallStaticJava()) {
312 CallStaticJavaNode* csj = receiver->in(0)->as_CallStaticJava();
313 ciMethod* m = csj->method();
314 if (m != NULL &&
315 (m->intrinsic_id() == vmIntrinsics::_StringBuffer_toString ||
316 m->intrinsic_id() == vmIntrinsics::_StringBuilder_toString))
317 // Delay String.<init>(new SB())
318 return true;
319 }
320 return false;
321 }
323 default:
324 return false;
325 }
326 }
327 return false;
328 }
331 // uncommon-trap call-sites where callee is unloaded, uninitialized or will not link
332 bool Parse::can_not_compile_call_site(ciMethod *dest_method, ciInstanceKlass* klass) {
333 // Additional inputs to consider...
334 // bc = bc()
335 // caller = method()
336 // iter().get_method_holder_index()
337 assert( dest_method->is_loaded(), "ciTypeFlow should not let us get here" );
338 // Interface classes can be loaded & linked and never get around to
339 // being initialized. Uncommon-trap for not-initialized static or
340 // v-calls. Let interface calls happen.
341 ciInstanceKlass* holder_klass = dest_method->holder();
342 if (!holder_klass->is_being_initialized() &&
343 !holder_klass->is_initialized() &&
344 !holder_klass->is_interface()) {
345 uncommon_trap(Deoptimization::Reason_uninitialized,
346 Deoptimization::Action_reinterpret,
347 holder_klass);
348 return true;
349 }
351 assert(dest_method->is_loaded(), "dest_method: typeflow responsibility");
352 return false;
353 }
356 //------------------------------do_call----------------------------------------
357 // Handle your basic call. Inline if we can & want to, else just setup call.
358 void Parse::do_call() {
359 // It's likely we are going to add debug info soon.
360 // Also, if we inline a guy who eventually needs debug info for this JVMS,
361 // our contribution to it is cleaned up right here.
362 kill_dead_locals();
364 // Set frequently used booleans
365 const bool is_virtual = bc() == Bytecodes::_invokevirtual;
366 const bool is_virtual_or_interface = is_virtual || bc() == Bytecodes::_invokeinterface;
367 const bool has_receiver = Bytecodes::has_receiver(bc());
369 // Find target being called
370 bool will_link;
371 ciSignature* declared_signature = NULL;
372 ciMethod* orig_callee = iter().get_method(will_link, &declared_signature); // callee in the bytecode
373 ciInstanceKlass* holder_klass = orig_callee->holder();
374 ciKlass* holder = iter().get_declared_method_holder();
375 ciInstanceKlass* klass = ciEnv::get_instance_klass_for_declared_method_holder(holder);
376 assert(declared_signature != NULL, "cannot be null");
378 // uncommon-trap when callee is unloaded, uninitialized or will not link
379 // bailout when too many arguments for register representation
380 if (!will_link || can_not_compile_call_site(orig_callee, klass)) {
381 #ifndef PRODUCT
382 if (PrintOpto && (Verbose || WizardMode)) {
383 method()->print_name(); tty->print_cr(" can not compile call at bci %d to:", bci());
384 orig_callee->print_name(); tty->cr();
385 }
386 #endif
387 return;
388 }
389 assert(holder_klass->is_loaded(), "");
390 //assert((bc_callee->is_static() || is_invokedynamic) == !has_receiver , "must match bc"); // XXX invokehandle (cur_bc_raw)
391 // Note: this takes into account invokeinterface of methods declared in java/lang/Object,
392 // which should be invokevirtuals but according to the VM spec may be invokeinterfaces
393 assert(holder_klass->is_interface() || holder_klass->super() == NULL || (bc() != Bytecodes::_invokeinterface), "must match bc");
394 // Note: In the absence of miranda methods, an abstract class K can perform
395 // an invokevirtual directly on an interface method I.m if K implements I.
397 // orig_callee is the resolved callee which's signature includes the
398 // appendix argument.
399 const int nargs = orig_callee->arg_size();
400 const bool is_signature_polymorphic = MethodHandles::is_signature_polymorphic(orig_callee->intrinsic_id());
402 // Push appendix argument (MethodType, CallSite, etc.), if one.
403 if (iter().has_appendix()) {
404 ciObject* appendix_arg = iter().get_appendix();
405 const TypeOopPtr* appendix_arg_type = TypeOopPtr::make_from_constant(appendix_arg);
406 Node* appendix_arg_node = _gvn.makecon(appendix_arg_type);
407 push(appendix_arg_node);
408 }
410 // ---------------------
411 // Does Class Hierarchy Analysis reveal only a single target of a v-call?
412 // Then we may inline or make a static call, but become dependent on there being only 1 target.
413 // Does the call-site type profile reveal only one receiver?
414 // Then we may introduce a run-time check and inline on the path where it succeeds.
415 // The other path may uncommon_trap, check for another receiver, or do a v-call.
417 // Try to get the most accurate receiver type
418 ciMethod* callee = orig_callee;
419 int vtable_index = Method::invalid_vtable_index;
420 bool call_does_dispatch = false;
422 if (is_virtual_or_interface) {
423 Node* receiver_node = stack(sp() - nargs);
424 const TypeOopPtr* receiver_type = _gvn.type(receiver_node)->isa_oopptr();
425 // call_does_dispatch and vtable_index are out-parameters. They might be changed.
426 callee = C->optimize_virtual_call(method(), bci(), klass, orig_callee, receiver_type,
427 is_virtual,
428 call_does_dispatch, vtable_index); // out-parameters
429 }
431 // Note: It's OK to try to inline a virtual call.
432 // The call generator will not attempt to inline a polymorphic call
433 // unless it knows how to optimize the receiver dispatch.
434 bool try_inline = (C->do_inlining() || InlineAccessors);
436 // ---------------------
437 dec_sp(nargs); // Temporarily pop args for JVM state of call
438 JVMState* jvms = sync_jvms();
440 // ---------------------
441 // Decide call tactic.
442 // This call checks with CHA, the interpreter profile, intrinsics table, etc.
443 // It decides whether inlining is desirable or not.
444 CallGenerator* cg = C->call_generator(callee, vtable_index, call_does_dispatch, jvms, try_inline, prof_factor());
446 // NOTE: Don't use orig_callee and callee after this point! Use cg->method() instead.
447 orig_callee = callee = NULL;
449 // ---------------------
450 // Round double arguments before call
451 round_double_arguments(cg->method());
453 #ifndef PRODUCT
454 // bump global counters for calls
455 count_compiled_calls(/*at_method_entry*/ false, cg->is_inline());
457 // Record first part of parsing work for this call
458 parse_histogram()->record_change();
459 #endif // not PRODUCT
461 assert(jvms == this->jvms(), "still operating on the right JVMS");
462 assert(jvms_in_sync(), "jvms must carry full info into CG");
464 // save across call, for a subsequent cast_not_null.
465 Node* receiver = has_receiver ? argument(0) : NULL;
467 // Bump method data counters (We profile *before* the call is made
468 // because exceptions don't return to the call site.)
469 profile_call(receiver);
471 JVMState* new_jvms = cg->generate(jvms);
472 if (new_jvms == NULL) {
473 // When inlining attempt fails (e.g., too many arguments),
474 // it may contaminate the current compile state, making it
475 // impossible to pull back and try again. Once we call
476 // cg->generate(), we are committed. If it fails, the whole
477 // compilation task is compromised.
478 if (failing()) return;
480 // This can happen if a library intrinsic is available, but refuses
481 // the call site, perhaps because it did not match a pattern the
482 // intrinsic was expecting to optimize. Should always be possible to
483 // get a normal java call that may inline in that case
484 cg = C->call_generator(cg->method(), vtable_index, call_does_dispatch, jvms, try_inline, prof_factor(), /* allow_intrinsics= */ false);
485 if ((new_jvms = cg->generate(jvms)) == NULL) {
486 guarantee(failing(), "call failed to generate: calls should work");
487 return;
488 }
489 }
491 if (cg->is_inline()) {
492 // Accumulate has_loops estimate
493 C->set_has_loops(C->has_loops() || cg->method()->has_loops());
494 C->env()->notice_inlined_method(cg->method());
495 }
497 // Reset parser state from [new_]jvms, which now carries results of the call.
498 // Return value (if any) is already pushed on the stack by the cg.
499 add_exception_states_from(new_jvms);
500 if (new_jvms->map()->control() == top()) {
501 stop_and_kill_map();
502 } else {
503 assert(new_jvms->same_calls_as(jvms), "method/bci left unchanged");
504 set_jvms(new_jvms);
505 }
507 if (!stopped()) {
508 // This was some sort of virtual call, which did a null check for us.
509 // Now we can assert receiver-not-null, on the normal return path.
510 if (receiver != NULL && cg->is_virtual()) {
511 Node* cast = cast_not_null(receiver);
512 // %%% assert(receiver == cast, "should already have cast the receiver");
513 }
515 // Round double result after a call from strict to non-strict code
516 round_double_result(cg->method());
518 ciType* rtype = cg->method()->return_type();
519 ciType* ctype = declared_signature->return_type();
521 if (Bytecodes::has_optional_appendix(iter().cur_bc_raw()) || is_signature_polymorphic) {
522 // Be careful here with return types.
523 if (ctype != rtype) {
524 BasicType rt = rtype->basic_type();
525 BasicType ct = ctype->basic_type();
526 if (ct == T_VOID) {
527 // It's OK for a method to return a value that is discarded.
528 // The discarding does not require any special action from the caller.
529 // The Java code knows this, at VerifyType.isNullConversion.
530 pop_node(rt); // whatever it was, pop it
531 } else if (rt == T_INT || is_subword_type(rt)) {
532 // Nothing. These cases are handled in lambda form bytecode.
533 assert(ct == T_INT || is_subword_type(ct), err_msg_res("must match: rt=%s, ct=%s", type2name(rt), type2name(ct)));
534 } else if (rt == T_OBJECT || rt == T_ARRAY) {
535 assert(ct == T_OBJECT || ct == T_ARRAY, err_msg_res("rt=%s, ct=%s", type2name(rt), type2name(ct)));
536 if (ctype->is_loaded()) {
537 const TypeOopPtr* arg_type = TypeOopPtr::make_from_klass(rtype->as_klass());
538 const Type* sig_type = TypeOopPtr::make_from_klass(ctype->as_klass());
539 if (arg_type != NULL && !arg_type->higher_equal(sig_type)) {
540 Node* retnode = pop();
541 Node* cast_obj = _gvn.transform(new (C) CheckCastPPNode(control(), retnode, sig_type));
542 push(cast_obj);
543 }
544 }
545 } else {
546 assert(rt == ct, err_msg_res("unexpected mismatch: rt=%s, ct=%s", type2name(rt), type2name(ct)));
547 // push a zero; it's better than getting an oop/int mismatch
548 pop_node(rt);
549 Node* retnode = zerocon(ct);
550 push_node(ct, retnode);
551 }
552 // Now that the value is well-behaved, continue with the call-site type.
553 rtype = ctype;
554 }
555 } else {
556 // Symbolic resolution enforces the types to be the same.
557 // NOTE: We must relax the assert for unloaded types because two
558 // different ciType instances of the same unloaded class type
559 // can appear to be "loaded" by different loaders (depending on
560 // the accessing class).
561 assert(!rtype->is_loaded() || !ctype->is_loaded() || rtype == ctype,
562 err_msg_res("mismatched return types: rtype=%s, ctype=%s", rtype->name(), ctype->name()));
563 }
565 // If the return type of the method is not loaded, assert that the
566 // value we got is a null. Otherwise, we need to recompile.
567 if (!rtype->is_loaded()) {
568 #ifndef PRODUCT
569 if (PrintOpto && (Verbose || WizardMode)) {
570 method()->print_name(); tty->print_cr(" asserting nullness of result at bci: %d", bci());
571 cg->method()->print_name(); tty->cr();
572 }
573 #endif
574 if (C->log() != NULL) {
575 C->log()->elem("assert_null reason='return' klass='%d'",
576 C->log()->identify(rtype));
577 }
578 // If there is going to be a trap, put it at the next bytecode:
579 set_bci(iter().next_bci());
580 null_assert(peek());
581 set_bci(iter().cur_bci()); // put it back
582 }
583 }
585 // Restart record of parsing work after possible inlining of call
586 #ifndef PRODUCT
587 parse_histogram()->set_initial_state(bc());
588 #endif
589 }
591 //---------------------------catch_call_exceptions-----------------------------
592 // Put a Catch and CatchProj nodes behind a just-created call.
593 // Send their caught exceptions to the proper handler.
594 // This may be used after a call to the rethrow VM stub,
595 // when it is needed to process unloaded exception classes.
596 void Parse::catch_call_exceptions(ciExceptionHandlerStream& handlers) {
597 // Exceptions are delivered through this channel:
598 Node* i_o = this->i_o();
600 // Add a CatchNode.
601 GrowableArray<int>* bcis = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, -1);
602 GrowableArray<const Type*>* extypes = new (C->node_arena()) GrowableArray<const Type*>(C->node_arena(), 8, 0, NULL);
603 GrowableArray<int>* saw_unloaded = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, 0);
605 for (; !handlers.is_done(); handlers.next()) {
606 ciExceptionHandler* h = handlers.handler();
607 int h_bci = h->handler_bci();
608 ciInstanceKlass* h_klass = h->is_catch_all() ? env()->Throwable_klass() : h->catch_klass();
609 // Do not introduce unloaded exception types into the graph:
610 if (!h_klass->is_loaded()) {
611 if (saw_unloaded->contains(h_bci)) {
612 /* We've already seen an unloaded exception with h_bci,
613 so don't duplicate. Duplication will cause the CatchNode to be
614 unnecessarily large. See 4713716. */
615 continue;
616 } else {
617 saw_unloaded->append(h_bci);
618 }
619 }
620 const Type* h_extype = TypeOopPtr::make_from_klass(h_klass);
621 // (We use make_from_klass because it respects UseUniqueSubclasses.)
622 h_extype = h_extype->join(TypeInstPtr::NOTNULL);
623 assert(!h_extype->empty(), "sanity");
624 // Note: It's OK if the BCIs repeat themselves.
625 bcis->append(h_bci);
626 extypes->append(h_extype);
627 }
629 int len = bcis->length();
630 CatchNode *cn = new (C) CatchNode(control(), i_o, len+1);
631 Node *catch_ = _gvn.transform(cn);
633 // now branch with the exception state to each of the (potential)
634 // handlers
635 for(int i=0; i < len; i++) {
636 // Setup JVM state to enter the handler.
637 PreserveJVMState pjvms(this);
638 // Locals are just copied from before the call.
639 // Get control from the CatchNode.
640 int handler_bci = bcis->at(i);
641 Node* ctrl = _gvn.transform( new (C) CatchProjNode(catch_, i+1,handler_bci));
642 // This handler cannot happen?
643 if (ctrl == top()) continue;
644 set_control(ctrl);
646 // Create exception oop
647 const TypeInstPtr* extype = extypes->at(i)->is_instptr();
648 Node *ex_oop = _gvn.transform(new (C) CreateExNode(extypes->at(i), ctrl, i_o));
650 // Handle unloaded exception classes.
651 if (saw_unloaded->contains(handler_bci)) {
652 // An unloaded exception type is coming here. Do an uncommon trap.
653 #ifndef PRODUCT
654 // We do not expect the same handler bci to take both cold unloaded
655 // and hot loaded exceptions. But, watch for it.
656 if ((Verbose || WizardMode) && extype->is_loaded()) {
657 tty->print("Warning: Handler @%d takes mixed loaded/unloaded exceptions in ", bci());
658 method()->print_name(); tty->cr();
659 } else if (PrintOpto && (Verbose || WizardMode)) {
660 tty->print("Bailing out on unloaded exception type ");
661 extype->klass()->print_name();
662 tty->print(" at bci:%d in ", bci());
663 method()->print_name(); tty->cr();
664 }
665 #endif
666 // Emit an uncommon trap instead of processing the block.
667 set_bci(handler_bci);
668 push_ex_oop(ex_oop);
669 uncommon_trap(Deoptimization::Reason_unloaded,
670 Deoptimization::Action_reinterpret,
671 extype->klass(), "!loaded exception");
672 set_bci(iter().cur_bci()); // put it back
673 continue;
674 }
676 // go to the exception handler
677 if (handler_bci < 0) { // merge with corresponding rethrow node
678 throw_to_exit(make_exception_state(ex_oop));
679 } else { // Else jump to corresponding handle
680 push_ex_oop(ex_oop); // Clear stack and push just the oop.
681 merge_exception(handler_bci);
682 }
683 }
685 // The first CatchProj is for the normal return.
686 // (Note: If this is a call to rethrow_Java, this node goes dead.)
687 set_control(_gvn.transform( new (C) CatchProjNode(catch_, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci)));
688 }
691 //----------------------------catch_inline_exceptions--------------------------
692 // Handle all exceptions thrown by an inlined method or individual bytecode.
693 // Common case 1: we have no handler, so all exceptions merge right into
694 // the rethrow case.
695 // Case 2: we have some handlers, with loaded exception klasses that have
696 // no subklasses. We do a Deutsch-Shiffman style type-check on the incoming
697 // exception oop and branch to the handler directly.
698 // Case 3: We have some handlers with subklasses or are not loaded at
699 // compile-time. We have to call the runtime to resolve the exception.
700 // So we insert a RethrowCall and all the logic that goes with it.
701 void Parse::catch_inline_exceptions(SafePointNode* ex_map) {
702 // Caller is responsible for saving away the map for normal control flow!
703 assert(stopped(), "call set_map(NULL) first");
704 assert(method()->has_exception_handlers(), "don't come here w/o work to do");
706 Node* ex_node = saved_ex_oop(ex_map);
707 if (ex_node == top()) {
708 // No action needed.
709 return;
710 }
711 const TypeInstPtr* ex_type = _gvn.type(ex_node)->isa_instptr();
712 NOT_PRODUCT(if (ex_type==NULL) tty->print_cr("*** Exception not InstPtr"));
713 if (ex_type == NULL)
714 ex_type = TypeOopPtr::make_from_klass(env()->Throwable_klass())->is_instptr();
716 // determine potential exception handlers
717 ciExceptionHandlerStream handlers(method(), bci(),
718 ex_type->klass()->as_instance_klass(),
719 ex_type->klass_is_exact());
721 // Start executing from the given throw state. (Keep its stack, for now.)
722 // Get the exception oop as known at compile time.
723 ex_node = use_exception_state(ex_map);
725 // Get the exception oop klass from its header
726 Node* ex_klass_node = NULL;
727 if (has_ex_handler() && !ex_type->klass_is_exact()) {
728 Node* p = basic_plus_adr( ex_node, ex_node, oopDesc::klass_offset_in_bytes());
729 ex_klass_node = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT) );
731 // Compute the exception klass a little more cleverly.
732 // Obvious solution is to simple do a LoadKlass from the 'ex_node'.
733 // However, if the ex_node is a PhiNode, I'm going to do a LoadKlass for
734 // each arm of the Phi. If I know something clever about the exceptions
735 // I'm loading the class from, I can replace the LoadKlass with the
736 // klass constant for the exception oop.
737 if( ex_node->is_Phi() ) {
738 ex_klass_node = new (C) PhiNode( ex_node->in(0), TypeKlassPtr::OBJECT );
739 for( uint i = 1; i < ex_node->req(); i++ ) {
740 Node* p = basic_plus_adr( ex_node->in(i), ex_node->in(i), oopDesc::klass_offset_in_bytes() );
741 Node* k = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT) );
742 ex_klass_node->init_req( i, k );
743 }
744 _gvn.set_type(ex_klass_node, TypeKlassPtr::OBJECT);
746 }
747 }
749 // Scan the exception table for applicable handlers.
750 // If none, we can call rethrow() and be done!
751 // If precise (loaded with no subklasses), insert a D.S. style
752 // pointer compare to the correct handler and loop back.
753 // If imprecise, switch to the Rethrow VM-call style handling.
755 int remaining = handlers.count_remaining();
757 // iterate through all entries sequentially
758 for (;!handlers.is_done(); handlers.next()) {
759 ciExceptionHandler* handler = handlers.handler();
761 if (handler->is_rethrow()) {
762 // If we fell off the end of the table without finding an imprecise
763 // exception klass (and without finding a generic handler) then we
764 // know this exception is not handled in this method. We just rethrow
765 // the exception into the caller.
766 throw_to_exit(make_exception_state(ex_node));
767 return;
768 }
770 // exception handler bci range covers throw_bci => investigate further
771 int handler_bci = handler->handler_bci();
773 if (remaining == 1) {
774 push_ex_oop(ex_node); // Push exception oop for handler
775 #ifndef PRODUCT
776 if (PrintOpto && WizardMode) {
777 tty->print_cr(" Catching every inline exception bci:%d -> handler_bci:%d", bci(), handler_bci);
778 }
779 #endif
780 merge_exception(handler_bci); // jump to handler
781 return; // No more handling to be done here!
782 }
784 // Get the handler's klass
785 ciInstanceKlass* klass = handler->catch_klass();
787 if (!klass->is_loaded()) { // klass is not loaded?
788 // fall through into catch_call_exceptions which will emit a
789 // handler with an uncommon trap.
790 break;
791 }
793 if (klass->is_interface()) // should not happen, but...
794 break; // bail out
796 // Check the type of the exception against the catch type
797 const TypeKlassPtr *tk = TypeKlassPtr::make(klass);
798 Node* con = _gvn.makecon(tk);
799 Node* not_subtype_ctrl = gen_subtype_check(ex_klass_node, con);
800 if (!stopped()) {
801 PreserveJVMState pjvms(this);
802 const TypeInstPtr* tinst = TypeOopPtr::make_from_klass_unique(klass)->cast_to_ptr_type(TypePtr::NotNull)->is_instptr();
803 assert(klass->has_subklass() || tinst->klass_is_exact(), "lost exactness");
804 Node* ex_oop = _gvn.transform(new (C) CheckCastPPNode(control(), ex_node, tinst));
805 push_ex_oop(ex_oop); // Push exception oop for handler
806 #ifndef PRODUCT
807 if (PrintOpto && WizardMode) {
808 tty->print(" Catching inline exception bci:%d -> handler_bci:%d -- ", bci(), handler_bci);
809 klass->print_name();
810 tty->cr();
811 }
812 #endif
813 merge_exception(handler_bci);
814 }
815 set_control(not_subtype_ctrl);
817 // Come here if exception does not match handler.
818 // Carry on with more handler checks.
819 --remaining;
820 }
822 assert(!stopped(), "you should return if you finish the chain");
824 // Oops, need to call into the VM to resolve the klasses at runtime.
825 // Note: This call must not deoptimize, since it is not a real at this bci!
826 kill_dead_locals();
828 make_runtime_call(RC_NO_LEAF | RC_MUST_THROW,
829 OptoRuntime::rethrow_Type(),
830 OptoRuntime::rethrow_stub(),
831 NULL, NULL,
832 ex_node);
834 // Rethrow is a pure call, no side effects, only a result.
835 // The result cannot be allocated, so we use I_O
837 // Catch exceptions from the rethrow
838 catch_call_exceptions(handlers);
839 }
842 // (Note: Moved add_debug_info into GraphKit::add_safepoint_edges.)
845 #ifndef PRODUCT
846 void Parse::count_compiled_calls(bool at_method_entry, bool is_inline) {
847 if( CountCompiledCalls ) {
848 if( at_method_entry ) {
849 // bump invocation counter if top method (for statistics)
850 if (CountCompiledCalls && depth() == 1) {
851 const TypePtr* addr_type = TypeMetadataPtr::make(method());
852 Node* adr1 = makecon(addr_type);
853 Node* adr2 = basic_plus_adr(adr1, adr1, in_bytes(Method::compiled_invocation_counter_offset()));
854 increment_counter(adr2);
855 }
856 } else if (is_inline) {
857 switch (bc()) {
858 case Bytecodes::_invokevirtual: increment_counter(SharedRuntime::nof_inlined_calls_addr()); break;
859 case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_inlined_interface_calls_addr()); break;
860 case Bytecodes::_invokestatic:
861 case Bytecodes::_invokedynamic:
862 case Bytecodes::_invokespecial: increment_counter(SharedRuntime::nof_inlined_static_calls_addr()); break;
863 default: fatal("unexpected call bytecode");
864 }
865 } else {
866 switch (bc()) {
867 case Bytecodes::_invokevirtual: increment_counter(SharedRuntime::nof_normal_calls_addr()); break;
868 case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_interface_calls_addr()); break;
869 case Bytecodes::_invokestatic:
870 case Bytecodes::_invokedynamic:
871 case Bytecodes::_invokespecial: increment_counter(SharedRuntime::nof_static_calls_addr()); break;
872 default: fatal("unexpected call bytecode");
873 }
874 }
875 }
876 }
877 #endif //PRODUCT
880 ciMethod* Compile::optimize_virtual_call(ciMethod* caller, int bci, ciInstanceKlass* klass,
881 ciMethod* callee, const TypeOopPtr* receiver_type,
882 bool is_virtual,
883 bool& call_does_dispatch, int& vtable_index) {
884 // Set default values for out-parameters.
885 call_does_dispatch = true;
886 vtable_index = Method::invalid_vtable_index;
888 // Choose call strategy.
889 ciMethod* optimized_virtual_method = optimize_inlining(caller, bci, klass, callee, receiver_type);
891 // Have the call been sufficiently improved such that it is no longer a virtual?
892 if (optimized_virtual_method != NULL) {
893 callee = optimized_virtual_method;
894 call_does_dispatch = false;
895 } else if (!UseInlineCaches && is_virtual && callee->is_loaded()) {
896 // We can make a vtable call at this site
897 vtable_index = callee->resolve_vtable_index(caller->holder(), klass);
898 }
899 return callee;
900 }
902 // Identify possible target method and inlining style
903 ciMethod* Compile::optimize_inlining(ciMethod* caller, int bci, ciInstanceKlass* klass,
904 ciMethod* callee, const TypeOopPtr* receiver_type) {
905 // only use for virtual or interface calls
907 // If it is obviously final, do not bother to call find_monomorphic_target,
908 // because the class hierarchy checks are not needed, and may fail due to
909 // incompletely loaded classes. Since we do our own class loading checks
910 // in this module, we may confidently bind to any method.
911 if (callee->can_be_statically_bound()) {
912 return callee;
913 }
915 // Attempt to improve the receiver
916 bool actual_receiver_is_exact = false;
917 ciInstanceKlass* actual_receiver = klass;
918 if (receiver_type != NULL) {
919 // Array methods are all inherited from Object, and are monomorphic.
920 if (receiver_type->isa_aryptr() &&
921 callee->holder() == env()->Object_klass()) {
922 return callee;
923 }
925 // All other interesting cases are instance klasses.
926 if (!receiver_type->isa_instptr()) {
927 return NULL;
928 }
930 ciInstanceKlass *ikl = receiver_type->klass()->as_instance_klass();
931 if (ikl->is_loaded() && ikl->is_initialized() && !ikl->is_interface() &&
932 (ikl == actual_receiver || ikl->is_subtype_of(actual_receiver))) {
933 // ikl is a same or better type than the original actual_receiver,
934 // e.g. static receiver from bytecodes.
935 actual_receiver = ikl;
936 // Is the actual_receiver exact?
937 actual_receiver_is_exact = receiver_type->klass_is_exact();
938 }
939 }
941 ciInstanceKlass* calling_klass = caller->holder();
942 ciMethod* cha_monomorphic_target = callee->find_monomorphic_target(calling_klass, klass, actual_receiver);
943 if (cha_monomorphic_target != NULL) {
944 assert(!cha_monomorphic_target->is_abstract(), "");
945 // Look at the method-receiver type. Does it add "too much information"?
946 ciKlass* mr_klass = cha_monomorphic_target->holder();
947 const Type* mr_type = TypeInstPtr::make(TypePtr::BotPTR, mr_klass);
948 if (receiver_type == NULL || !receiver_type->higher_equal(mr_type)) {
949 // Calling this method would include an implicit cast to its holder.
950 // %%% Not yet implemented. Would throw minor asserts at present.
951 // %%% The most common wins are already gained by +UseUniqueSubclasses.
952 // To fix, put the higher_equal check at the call of this routine,
953 // and add a CheckCastPP to the receiver.
954 if (TraceDependencies) {
955 tty->print_cr("found unique CHA method, but could not cast up");
956 tty->print(" method = ");
957 cha_monomorphic_target->print();
958 tty->cr();
959 }
960 if (log() != NULL) {
961 log()->elem("missed_CHA_opportunity klass='%d' method='%d'",
962 log()->identify(klass),
963 log()->identify(cha_monomorphic_target));
964 }
965 cha_monomorphic_target = NULL;
966 }
967 }
968 if (cha_monomorphic_target != NULL) {
969 // Hardwiring a virtual.
970 // If we inlined because CHA revealed only a single target method,
971 // then we are dependent on that target method not getting overridden
972 // by dynamic class loading. Be sure to test the "static" receiver
973 // dest_method here, as opposed to the actual receiver, which may
974 // falsely lead us to believe that the receiver is final or private.
975 dependencies()->assert_unique_concrete_method(actual_receiver, cha_monomorphic_target);
976 return cha_monomorphic_target;
977 }
979 // If the type is exact, we can still bind the method w/o a vcall.
980 // (This case comes after CHA so we can see how much extra work it does.)
981 if (actual_receiver_is_exact) {
982 // In case of evolution, there is a dependence on every inlined method, since each
983 // such method can be changed when its class is redefined.
984 ciMethod* exact_method = callee->resolve_invoke(calling_klass, actual_receiver);
985 if (exact_method != NULL) {
986 #ifndef PRODUCT
987 if (PrintOpto) {
988 tty->print(" Calling method via exact type @%d --- ", bci);
989 exact_method->print_name();
990 tty->cr();
991 }
992 #endif
993 return exact_method;
994 }
995 }
997 return NULL;
998 }