1 /*
2 * Copyright (c) 1997, 2017, 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 */
24
25 #include "precompiled.hpp"
26 #include "asm/macroAssembler.hpp"
27 #include "asm/macroAssembler.inline.hpp"
28 #include "ci/ciReplay.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "code/exceptionHandlerTable.hpp"
31 #include "code/nmethod.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/compileLog.hpp"
34 #include "compiler/disassembler.hpp"
35 #include "compiler/oopMap.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "opto/addnode.hpp"
38 #include "opto/block.hpp"
39 #include "opto/c2compiler.hpp"
40 #include "opto/callGenerator.hpp"
41 #include "opto/callnode.hpp"
42 #include "opto/castnode.hpp"
43 #include "opto/cfgnode.hpp"
44 #include "opto/chaitin.hpp"
45 #include "opto/compile.hpp"
46 #include "opto/connode.hpp"
47 #include "opto/convertnode.hpp"
48 #include "opto/divnode.hpp"
49 #include "opto/escape.hpp"
50 #include "opto/idealGraphPrinter.hpp"
51 #include "opto/loopnode.hpp"
52 #include "opto/machnode.hpp"
53 #include "opto/macro.hpp"
54 #include "opto/matcher.hpp"
55 #include "opto/mathexactnode.hpp"
56 #include "opto/memnode.hpp"
57 #include "opto/mulnode.hpp"
58 #include "opto/narrowptrnode.hpp"
59 #include "opto/node.hpp"
60 #include "opto/opcodes.hpp"
61 #include "opto/output.hpp"
62 #include "opto/parse.hpp"
63 #include "opto/phaseX.hpp"
64 #include "opto/rootnode.hpp"
65 #include "opto/runtime.hpp"
66 #include "opto/stringopts.hpp"
67 #include "opto/type.hpp"
68 #include "opto/valuetypenode.hpp"
69 #include "opto/vectornode.hpp"
70 #include "runtime/arguments.hpp"
71 #include "runtime/sharedRuntime.hpp"
72 #include "runtime/signature.hpp"
73 #include "runtime/stubRoutines.hpp"
74 #include "runtime/timer.hpp"
75 #include "utilities/align.hpp"
76 #include "utilities/copy.hpp"
77
78
79 // -------------------- Compile::mach_constant_base_node -----------------------
80 // Constant table base node singleton.
81 MachConstantBaseNode* Compile::mach_constant_base_node() {
82 if (_mach_constant_base_node == NULL) {
83 _mach_constant_base_node = new MachConstantBaseNode();
84 _mach_constant_base_node->add_req(C->root());
85 }
86 return _mach_constant_base_node;
87 }
88
89
90 /// Support for intrinsics.
91
92 // Return the index at which m must be inserted (or already exists).
93 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
94 class IntrinsicDescPair {
95 private:
96 ciMethod* _m;
97 bool _is_virtual;
98 public:
99 IntrinsicDescPair(ciMethod* m, bool is_virtual) : _m(m), _is_virtual(is_virtual) {}
100 static int compare(IntrinsicDescPair* const& key, CallGenerator* const& elt) {
101 ciMethod* m= elt->method();
102 ciMethod* key_m = key->_m;
103 if (key_m < m) return -1;
104 else if (key_m > m) return 1;
105 else {
106 bool is_virtual = elt->is_virtual();
107 bool key_virtual = key->_is_virtual;
108 if (key_virtual < is_virtual) return -1;
109 else if (key_virtual > is_virtual) return 1;
110 else return 0;
111 }
112 }
113 };
114 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual, bool& found) {
115 #ifdef ASSERT
116 for (int i = 1; i < _intrinsics->length(); i++) {
117 CallGenerator* cg1 = _intrinsics->at(i-1);
118 CallGenerator* cg2 = _intrinsics->at(i);
119 assert(cg1->method() != cg2->method()
120 ? cg1->method() < cg2->method()
121 : cg1->is_virtual() < cg2->is_virtual(),
122 "compiler intrinsics list must stay sorted");
123 }
124 #endif
125 IntrinsicDescPair pair(m, is_virtual);
126 return _intrinsics->find_sorted<IntrinsicDescPair*, IntrinsicDescPair::compare>(&pair, found);
127 }
128
129 void Compile::register_intrinsic(CallGenerator* cg) {
130 if (_intrinsics == NULL) {
131 _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
132 }
133 int len = _intrinsics->length();
134 bool found = false;
135 int index = intrinsic_insertion_index(cg->method(), cg->is_virtual(), found);
136 assert(!found, "registering twice");
137 _intrinsics->insert_before(index, cg);
138 assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
139 }
140
141 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
142 assert(m->is_loaded(), "don't try this on unloaded methods");
143 if (_intrinsics != NULL) {
144 bool found = false;
145 int index = intrinsic_insertion_index(m, is_virtual, found);
146 if (found) {
147 return _intrinsics->at(index);
148 }
149 }
150 // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
151 if (m->intrinsic_id() != vmIntrinsics::_none &&
152 m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
153 CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
154 if (cg != NULL) {
155 // Save it for next time:
156 register_intrinsic(cg);
157 return cg;
158 } else {
159 gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
160 }
161 }
162 return NULL;
163 }
164
165 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
166 // in library_call.cpp.
167
168
169 #ifndef PRODUCT
170 // statistics gathering...
171
172 juint Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
173 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
174
175 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
176 assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
177 int oflags = _intrinsic_hist_flags[id];
178 assert(flags != 0, "what happened?");
179 if (is_virtual) {
180 flags |= _intrinsic_virtual;
181 }
182 bool changed = (flags != oflags);
183 if ((flags & _intrinsic_worked) != 0) {
184 juint count = (_intrinsic_hist_count[id] += 1);
185 if (count == 1) {
186 changed = true; // first time
187 }
188 // increment the overall count also:
189 _intrinsic_hist_count[vmIntrinsics::_none] += 1;
190 }
191 if (changed) {
192 if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
193 // Something changed about the intrinsic's virtuality.
194 if ((flags & _intrinsic_virtual) != 0) {
195 // This is the first use of this intrinsic as a virtual call.
196 if (oflags != 0) {
197 // We already saw it as a non-virtual, so note both cases.
198 flags |= _intrinsic_both;
199 }
200 } else if ((oflags & _intrinsic_both) == 0) {
201 // This is the first use of this intrinsic as a non-virtual
202 flags |= _intrinsic_both;
203 }
204 }
205 _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
206 }
207 // update the overall flags also:
208 _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
209 return changed;
210 }
211
212 static char* format_flags(int flags, char* buf) {
213 buf[0] = 0;
214 if ((flags & Compile::_intrinsic_worked) != 0) strcat(buf, ",worked");
215 if ((flags & Compile::_intrinsic_failed) != 0) strcat(buf, ",failed");
216 if ((flags & Compile::_intrinsic_disabled) != 0) strcat(buf, ",disabled");
217 if ((flags & Compile::_intrinsic_virtual) != 0) strcat(buf, ",virtual");
218 if ((flags & Compile::_intrinsic_both) != 0) strcat(buf, ",nonvirtual");
219 if (buf[0] == 0) strcat(buf, ",");
220 assert(buf[0] == ',', "must be");
221 return &buf[1];
222 }
223
224 void Compile::print_intrinsic_statistics() {
225 char flagsbuf[100];
226 ttyLocker ttyl;
227 if (xtty != NULL) xtty->head("statistics type='intrinsic'");
228 tty->print_cr("Compiler intrinsic usage:");
229 juint total = _intrinsic_hist_count[vmIntrinsics::_none];
230 if (total == 0) total = 1; // avoid div0 in case of no successes
231 #define PRINT_STAT_LINE(name, c, f) \
232 tty->print_cr(" %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
233 for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
234 vmIntrinsics::ID id = (vmIntrinsics::ID) index;
235 int flags = _intrinsic_hist_flags[id];
236 juint count = _intrinsic_hist_count[id];
237 if ((flags | count) != 0) {
238 PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
239 }
240 }
241 PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
242 if (xtty != NULL) xtty->tail("statistics");
243 }
244
245 void Compile::print_statistics() {
246 { ttyLocker ttyl;
247 if (xtty != NULL) xtty->head("statistics type='opto'");
248 Parse::print_statistics();
249 PhaseCCP::print_statistics();
250 PhaseRegAlloc::print_statistics();
251 Scheduling::print_statistics();
252 PhasePeephole::print_statistics();
253 PhaseIdealLoop::print_statistics();
254 if (xtty != NULL) xtty->tail("statistics");
255 }
256 if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
257 // put this under its own <statistics> element.
258 print_intrinsic_statistics();
259 }
260 }
261 #endif //PRODUCT
262
263 // Support for bundling info
264 Bundle* Compile::node_bundling(const Node *n) {
265 assert(valid_bundle_info(n), "oob");
266 return &_node_bundling_base[n->_idx];
267 }
268
269 bool Compile::valid_bundle_info(const Node *n) {
270 return (_node_bundling_limit > n->_idx);
271 }
272
273
274 void Compile::gvn_replace_by(Node* n, Node* nn) {
275 for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
276 Node* use = n->last_out(i);
277 bool is_in_table = initial_gvn()->hash_delete(use);
278 uint uses_found = 0;
279 for (uint j = 0; j < use->len(); j++) {
280 if (use->in(j) == n) {
281 if (j < use->req())
282 use->set_req(j, nn);
283 else
284 use->set_prec(j, nn);
285 uses_found++;
286 }
287 }
288 if (is_in_table) {
289 // reinsert into table
290 initial_gvn()->hash_find_insert(use);
291 }
292 record_for_igvn(use);
293 i -= uses_found; // we deleted 1 or more copies of this edge
294 }
295 }
296
297
298 static inline bool not_a_node(const Node* n) {
299 if (n == NULL) return true;
300 if (((intptr_t)n & 1) != 0) return true; // uninitialized, etc.
301 if (*(address*)n == badAddress) return true; // kill by Node::destruct
302 return false;
303 }
304
305 // Identify all nodes that are reachable from below, useful.
306 // Use breadth-first pass that records state in a Unique_Node_List,
307 // recursive traversal is slower.
308 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
309 int estimated_worklist_size = live_nodes();
310 useful.map( estimated_worklist_size, NULL ); // preallocate space
311
312 // Initialize worklist
313 if (root() != NULL) { useful.push(root()); }
314 // If 'top' is cached, declare it useful to preserve cached node
315 if( cached_top_node() ) { useful.push(cached_top_node()); }
316
317 // Push all useful nodes onto the list, breadthfirst
318 for( uint next = 0; next < useful.size(); ++next ) {
319 assert( next < unique(), "Unique useful nodes < total nodes");
320 Node *n = useful.at(next);
321 uint max = n->len();
322 for( uint i = 0; i < max; ++i ) {
323 Node *m = n->in(i);
324 if (not_a_node(m)) continue;
325 useful.push(m);
326 }
327 }
328 }
329
330 // Update dead_node_list with any missing dead nodes using useful
331 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
332 void Compile::update_dead_node_list(Unique_Node_List &useful) {
333 uint max_idx = unique();
334 VectorSet& useful_node_set = useful.member_set();
335
336 for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
337 // If node with index node_idx is not in useful set,
338 // mark it as dead in dead node list.
339 if (! useful_node_set.test(node_idx) ) {
340 record_dead_node(node_idx);
341 }
342 }
343 }
344
345 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
346 int shift = 0;
347 for (int i = 0; i < inlines->length(); i++) {
348 CallGenerator* cg = inlines->at(i);
349 CallNode* call = cg->call_node();
350 if (shift > 0) {
351 inlines->at_put(i-shift, cg);
352 }
353 if (!useful.member(call)) {
354 shift++;
355 }
356 }
357 inlines->trunc_to(inlines->length()-shift);
358 }
359
360 // Disconnect all useless nodes by disconnecting those at the boundary.
361 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
362 uint next = 0;
363 while (next < useful.size()) {
364 Node *n = useful.at(next++);
365 if (n->is_SafePoint()) {
366 // We're done with a parsing phase. Replaced nodes are not valid
367 // beyond that point.
368 n->as_SafePoint()->delete_replaced_nodes();
369 }
370 // Use raw traversal of out edges since this code removes out edges
371 int max = n->outcnt();
372 for (int j = 0; j < max; ++j) {
373 Node* child = n->raw_out(j);
374 if (! useful.member(child)) {
375 assert(!child->is_top() || child != top(),
376 "If top is cached in Compile object it is in useful list");
377 // Only need to remove this out-edge to the useless node
378 n->raw_del_out(j);
379 --j;
380 --max;
381 }
382 }
383 if (n->outcnt() == 1 && n->has_special_unique_user()) {
384 record_for_igvn(n->unique_out());
385 }
386 }
387 // Remove useless macro and predicate opaq nodes
388 for (int i = C->macro_count()-1; i >= 0; i--) {
389 Node* n = C->macro_node(i);
390 if (!useful.member(n)) {
391 remove_macro_node(n);
392 }
393 }
394 // Remove useless CastII nodes with range check dependency
395 for (int i = range_check_cast_count() - 1; i >= 0; i--) {
396 Node* cast = range_check_cast_node(i);
397 if (!useful.member(cast)) {
398 remove_range_check_cast(cast);
399 }
400 }
401 // Remove useless expensive node
402 for (int i = C->expensive_count()-1; i >= 0; i--) {
403 Node* n = C->expensive_node(i);
404 if (!useful.member(n)) {
405 remove_expensive_node(n);
406 }
407 }
408 // Remove useless value type nodes
409 if (_value_type_nodes != NULL) {
410 _value_type_nodes->remove_useless_nodes(useful.member_set());
411 }
412 // clean up the late inline lists
413 remove_useless_late_inlines(&_string_late_inlines, useful);
414 remove_useless_late_inlines(&_boxing_late_inlines, useful);
415 remove_useless_late_inlines(&_late_inlines, useful);
416 debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
417 }
418
419 //------------------------------frame_size_in_words-----------------------------
420 // frame_slots in units of words
421 int Compile::frame_size_in_words() const {
422 // shift is 0 in LP32 and 1 in LP64
423 const int shift = (LogBytesPerWord - LogBytesPerInt);
424 int words = _frame_slots >> shift;
425 assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
426 return words;
427 }
428
429 // To bang the stack of this compiled method we use the stack size
430 // that the interpreter would need in case of a deoptimization. This
431 // removes the need to bang the stack in the deoptimization blob which
432 // in turn simplifies stack overflow handling.
433 int Compile::bang_size_in_bytes() const {
434 return MAX2(frame_size_in_bytes() + os::extra_bang_size_in_bytes(), _interpreter_frame_size);
435 }
436
437 // ============================================================================
438 //------------------------------CompileWrapper---------------------------------
439 class CompileWrapper : public StackObj {
440 Compile *const _compile;
441 public:
442 CompileWrapper(Compile* compile);
443
444 ~CompileWrapper();
445 };
446
447 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
448 // the Compile* pointer is stored in the current ciEnv:
449 ciEnv* env = compile->env();
450 assert(env == ciEnv::current(), "must already be a ciEnv active");
451 assert(env->compiler_data() == NULL, "compile already active?");
452 env->set_compiler_data(compile);
453 assert(compile == Compile::current(), "sanity");
454
455 compile->set_type_dict(NULL);
456 compile->set_clone_map(new Dict(cmpkey, hashkey, _compile->comp_arena()));
457 compile->clone_map().set_clone_idx(0);
458 compile->set_type_hwm(NULL);
459 compile->set_type_last_size(0);
460 compile->set_last_tf(NULL, NULL);
461 compile->set_indexSet_arena(NULL);
462 compile->set_indexSet_free_block_list(NULL);
463 compile->init_type_arena();
464 Type::Initialize(compile);
465 _compile->set_scratch_buffer_blob(NULL);
466 _compile->begin_method();
467 _compile->clone_map().set_debug(_compile->has_method() && _compile->directive()->CloneMapDebugOption);
468 }
469 CompileWrapper::~CompileWrapper() {
470 _compile->end_method();
471 if (_compile->scratch_buffer_blob() != NULL)
472 BufferBlob::free(_compile->scratch_buffer_blob());
473 _compile->env()->set_compiler_data(NULL);
474 }
475
476
477 //----------------------------print_compile_messages---------------------------
478 void Compile::print_compile_messages() {
479 #ifndef PRODUCT
480 // Check if recompiling
481 if (_subsume_loads == false && PrintOpto) {
482 // Recompiling without allowing machine instructions to subsume loads
483 tty->print_cr("*********************************************************");
484 tty->print_cr("** Bailout: Recompile without subsuming loads **");
485 tty->print_cr("*********************************************************");
486 }
487 if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
488 // Recompiling without escape analysis
489 tty->print_cr("*********************************************************");
490 tty->print_cr("** Bailout: Recompile without escape analysis **");
491 tty->print_cr("*********************************************************");
492 }
493 if (_eliminate_boxing != EliminateAutoBox && PrintOpto) {
494 // Recompiling without boxing elimination
495 tty->print_cr("*********************************************************");
496 tty->print_cr("** Bailout: Recompile without boxing elimination **");
497 tty->print_cr("*********************************************************");
498 }
499 if (C->directive()->BreakAtCompileOption) {
500 // Open the debugger when compiling this method.
501 tty->print("### Breaking when compiling: ");
502 method()->print_short_name();
503 tty->cr();
504 BREAKPOINT;
505 }
506
507 if( PrintOpto ) {
508 if (is_osr_compilation()) {
509 tty->print("[OSR]%3d", _compile_id);
510 } else {
511 tty->print("%3d", _compile_id);
512 }
513 }
514 #endif
515 }
516
517
518 //-----------------------init_scratch_buffer_blob------------------------------
519 // Construct a temporary BufferBlob and cache it for this compile.
520 void Compile::init_scratch_buffer_blob(int const_size) {
521 // If there is already a scratch buffer blob allocated and the
522 // constant section is big enough, use it. Otherwise free the
523 // current and allocate a new one.
524 BufferBlob* blob = scratch_buffer_blob();
525 if ((blob != NULL) && (const_size <= _scratch_const_size)) {
526 // Use the current blob.
527 } else {
528 if (blob != NULL) {
529 BufferBlob::free(blob);
530 }
531
532 ResourceMark rm;
533 _scratch_const_size = const_size;
534 int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
535 blob = BufferBlob::create("Compile::scratch_buffer", size);
536 // Record the buffer blob for next time.
537 set_scratch_buffer_blob(blob);
538 // Have we run out of code space?
539 if (scratch_buffer_blob() == NULL) {
540 // Let CompilerBroker disable further compilations.
541 record_failure("Not enough space for scratch buffer in CodeCache");
542 return;
543 }
544 }
545
546 // Initialize the relocation buffers
547 relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
548 set_scratch_locs_memory(locs_buf);
549 }
550
551
552 //-----------------------scratch_emit_size-------------------------------------
553 // Helper function that computes size by emitting code
554 uint Compile::scratch_emit_size(const Node* n) {
555 // Start scratch_emit_size section.
556 set_in_scratch_emit_size(true);
557
558 // Emit into a trash buffer and count bytes emitted.
559 // This is a pretty expensive way to compute a size,
560 // but it works well enough if seldom used.
561 // All common fixed-size instructions are given a size
562 // method by the AD file.
563 // Note that the scratch buffer blob and locs memory are
564 // allocated at the beginning of the compile task, and
565 // may be shared by several calls to scratch_emit_size.
566 // The allocation of the scratch buffer blob is particularly
567 // expensive, since it has to grab the code cache lock.
568 BufferBlob* blob = this->scratch_buffer_blob();
569 assert(blob != NULL, "Initialize BufferBlob at start");
570 assert(blob->size() > MAX_inst_size, "sanity");
571 relocInfo* locs_buf = scratch_locs_memory();
572 address blob_begin = blob->content_begin();
573 address blob_end = (address)locs_buf;
574 assert(blob->contains(blob_end), "sanity");
575 CodeBuffer buf(blob_begin, blob_end - blob_begin);
576 buf.initialize_consts_size(_scratch_const_size);
577 buf.initialize_stubs_size(MAX_stubs_size);
578 assert(locs_buf != NULL, "sanity");
579 int lsize = MAX_locs_size / 3;
580 buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
581 buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
582 buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
583 // Mark as scratch buffer.
584 buf.consts()->set_scratch_emit();
585 buf.insts()->set_scratch_emit();
586 buf.stubs()->set_scratch_emit();
587
588 // Do the emission.
589
590 Label fakeL; // Fake label for branch instructions.
591 Label* saveL = NULL;
592 uint save_bnum = 0;
593 bool is_branch = n->is_MachBranch();
594 if (is_branch) {
595 MacroAssembler masm(&buf);
596 masm.bind(fakeL);
597 n->as_MachBranch()->save_label(&saveL, &save_bnum);
598 n->as_MachBranch()->label_set(&fakeL, 0);
599 }
600 n->emit(buf, this->regalloc());
601
602 // Emitting into the scratch buffer should not fail
603 assert (!failing(), "Must not have pending failure. Reason is: %s", failure_reason());
604
605 if (is_branch) // Restore label.
606 n->as_MachBranch()->label_set(saveL, save_bnum);
607
608 // End scratch_emit_size section.
609 set_in_scratch_emit_size(false);
610
611 return buf.insts_size();
612 }
613
614
615 // ============================================================================
616 //------------------------------Compile standard-------------------------------
617 debug_only( int Compile::_debug_idx = 100000; )
618
619 // Compile a method. entry_bci is -1 for normal compilations and indicates
620 // the continuation bci for on stack replacement.
621
622
623 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci,
624 bool subsume_loads, bool do_escape_analysis, bool eliminate_boxing, DirectiveSet* directive)
625 : Phase(Compiler),
626 _env(ci_env),
627 _directive(directive),
628 _log(ci_env->log()),
629 _compile_id(ci_env->compile_id()),
630 _save_argument_registers(false),
631 _stub_name(NULL),
632 _stub_function(NULL),
633 _stub_entry_point(NULL),
634 _method(target),
635 _entry_bci(osr_bci),
636 _initial_gvn(NULL),
637 _for_igvn(NULL),
638 _warm_calls(NULL),
639 _subsume_loads(subsume_loads),
640 _do_escape_analysis(do_escape_analysis),
641 _eliminate_boxing(eliminate_boxing),
642 _failure_reason(NULL),
643 _code_buffer("Compile::Fill_buffer"),
644 _orig_pc_slot(0),
645 _orig_pc_slot_offset_in_bytes(0),
646 _has_method_handle_invokes(false),
647 _mach_constant_base_node(NULL),
648 _node_bundling_limit(0),
649 _node_bundling_base(NULL),
650 _java_calls(0),
651 _inner_loops(0),
652 _scratch_const_size(-1),
653 _in_scratch_emit_size(false),
654 _dead_node_list(comp_arena()),
655 _dead_node_count(0),
656 #ifndef PRODUCT
657 _trace_opto_output(directive->TraceOptoOutputOption),
658 _in_dump_cnt(0),
659 _printer(IdealGraphPrinter::printer()),
660 #endif
661 _congraph(NULL),
662 _comp_arena(mtCompiler),
663 _node_arena(mtCompiler),
664 _old_arena(mtCompiler),
665 _Compile_types(mtCompiler),
666 _replay_inline_data(NULL),
667 _late_inlines(comp_arena(), 2, 0, NULL),
668 _string_late_inlines(comp_arena(), 2, 0, NULL),
669 _boxing_late_inlines(comp_arena(), 2, 0, NULL),
670 _late_inlines_pos(0),
671 _number_of_mh_late_inlines(0),
672 _inlining_progress(false),
673 _inlining_incrementally(false),
674 _print_inlining_list(NULL),
675 _print_inlining_stream(NULL),
676 _print_inlining_idx(0),
677 _print_inlining_output(NULL),
678 _interpreter_frame_size(0),
679 _max_node_limit(MaxNodeLimit),
680 _has_reserved_stack_access(target->has_reserved_stack_access()) {
681 C = this;
682 #ifndef PRODUCT
683 if (_printer != NULL) {
684 _printer->set_compile(this);
685 }
686 #endif
687 CompileWrapper cw(this);
688
689 if (CITimeVerbose) {
690 tty->print(" ");
691 target->holder()->name()->print();
692 tty->print(".");
693 target->print_short_name();
694 tty->print(" ");
695 }
696 TraceTime t1("Total compilation time", &_t_totalCompilation, CITime, CITimeVerbose);
697 TraceTime t2(NULL, &_t_methodCompilation, CITime, false);
698
699 #ifndef PRODUCT
700 bool print_opto_assembly = directive->PrintOptoAssemblyOption;
701 if (!print_opto_assembly) {
702 bool print_assembly = directive->PrintAssemblyOption;
703 if (print_assembly && !Disassembler::can_decode()) {
704 tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
705 print_opto_assembly = true;
706 }
707 }
708 set_print_assembly(print_opto_assembly);
709 set_parsed_irreducible_loop(false);
710
711 if (directive->ReplayInlineOption) {
712 _replay_inline_data = ciReplay::load_inline_data(method(), entry_bci(), ci_env->comp_level());
713 }
714 #endif
715 set_print_inlining(directive->PrintInliningOption || PrintOptoInlining);
716 set_print_intrinsics(directive->PrintIntrinsicsOption);
717 set_has_irreducible_loop(true); // conservative until build_loop_tree() reset it
718
719 if (ProfileTraps RTM_OPT_ONLY( || UseRTMLocking )) {
720 // Make sure the method being compiled gets its own MDO,
721 // so we can at least track the decompile_count().
722 // Need MDO to record RTM code generation state.
723 method()->ensure_method_data();
724 }
725
726 Init(::AliasLevel);
727
728
729 print_compile_messages();
730
731 _ilt = InlineTree::build_inline_tree_root();
732
733 // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
734 assert(num_alias_types() >= AliasIdxRaw, "");
735
736 #define MINIMUM_NODE_HASH 1023
737 // Node list that Iterative GVN will start with
738 Unique_Node_List for_igvn(comp_arena());
739 set_for_igvn(&for_igvn);
740
741 // GVN that will be run immediately on new nodes
742 uint estimated_size = method()->code_size()*4+64;
743 estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
744 PhaseGVN gvn(node_arena(), estimated_size);
745 set_initial_gvn(&gvn);
746
747 print_inlining_init();
748 { // Scope for timing the parser
749 TracePhase tp("parse", &timers[_t_parser]);
750
751 // Put top into the hash table ASAP.
752 initial_gvn()->transform_no_reclaim(top());
753
754 // Set up tf(), start(), and find a CallGenerator.
755 CallGenerator* cg = NULL;
756 if (is_osr_compilation()) {
757 const TypeTuple *domain = StartOSRNode::osr_domain();
758 const TypeTuple *range = TypeTuple::make_range(method()->signature());
759 init_tf(TypeFunc::make(domain, range));
760 StartNode* s = new StartOSRNode(root(), domain);
761 initial_gvn()->set_type_bottom(s);
762 init_start(s);
763 cg = CallGenerator::for_osr(method(), entry_bci());
764 } else {
765 // Normal case.
766 init_tf(TypeFunc::make(method()));
767 StartNode* s = new StartNode(root(), tf()->domain_cc());
768 initial_gvn()->set_type_bottom(s);
769 init_start(s);
770 if (method()->intrinsic_id() == vmIntrinsics::_Reference_get && UseG1GC) {
771 // With java.lang.ref.reference.get() we must go through the
772 // intrinsic when G1 is enabled - even when get() is the root
773 // method of the compile - so that, if necessary, the value in
774 // the referent field of the reference object gets recorded by
775 // the pre-barrier code.
776 // Specifically, if G1 is enabled, the value in the referent
777 // field is recorded by the G1 SATB pre barrier. This will
778 // result in the referent being marked live and the reference
779 // object removed from the list of discovered references during
780 // reference processing.
781 cg = find_intrinsic(method(), false);
782 }
783 if (cg == NULL) {
784 float past_uses = method()->interpreter_invocation_count();
785 float expected_uses = past_uses;
786 cg = CallGenerator::for_inline(method(), expected_uses);
787 }
788 }
789 if (failing()) return;
790 if (cg == NULL) {
791 record_method_not_compilable("cannot parse method");
792 return;
793 }
794 JVMState* jvms = build_start_state(start(), tf());
795 if ((jvms = cg->generate(jvms)) == NULL) {
796 if (!failure_reason_is(C2Compiler::retry_class_loading_during_parsing())) {
797 record_method_not_compilable("method parse failed");
798 }
799 return;
800 }
801 GraphKit kit(jvms);
802
803 if (!kit.stopped()) {
804 // Accept return values, and transfer control we know not where.
805 // This is done by a special, unique ReturnNode bound to root.
806 return_values(kit.jvms());
807 }
808
809 if (kit.has_exceptions()) {
810 // Any exceptions that escape from this call must be rethrown
811 // to whatever caller is dynamically above us on the stack.
812 // This is done by a special, unique RethrowNode bound to root.
813 rethrow_exceptions(kit.transfer_exceptions_into_jvms());
814 }
815
816 assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
817
818 if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
819 inline_string_calls(true);
820 }
821
822 if (failing()) return;
823
824 print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
825
826 // Remove clutter produced by parsing.
827 if (!failing()) {
828 ResourceMark rm;
829 PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
830 }
831 }
832
833 // Note: Large methods are capped off in do_one_bytecode().
834 if (failing()) return;
835
836 // After parsing, node notes are no longer automagic.
837 // They must be propagated by register_new_node_with_optimizer(),
838 // clone(), or the like.
839 set_default_node_notes(NULL);
840
841 for (;;) {
842 int successes = Inline_Warm();
843 if (failing()) return;
844 if (successes == 0) break;
845 }
846
847 // Drain the list.
848 Finish_Warm();
849 #ifndef PRODUCT
850 if (_printer && _printer->should_print(1)) {
851 _printer->print_inlining();
852 }
853 #endif
854
855 if (failing()) return;
856 NOT_PRODUCT( verify_graph_edges(); )
857
858 // Now optimize
859 Optimize();
860 if (failing()) return;
861 NOT_PRODUCT( verify_graph_edges(); )
862
863 #ifndef PRODUCT
864 if (PrintIdeal) {
865 ttyLocker ttyl; // keep the following output all in one block
866 // This output goes directly to the tty, not the compiler log.
867 // To enable tools to match it up with the compilation activity,
868 // be sure to tag this tty output with the compile ID.
869 if (xtty != NULL) {
870 xtty->head("ideal compile_id='%d'%s", compile_id(),
871 is_osr_compilation() ? " compile_kind='osr'" :
872 "");
873 }
874 root()->dump(9999);
875 if (xtty != NULL) {
876 xtty->tail("ideal");
877 }
878 }
879 #endif
880
881 NOT_PRODUCT( verify_barriers(); )
882
883 // Dump compilation data to replay it.
884 if (directive->DumpReplayOption) {
885 env()->dump_replay_data(_compile_id);
886 }
887 if (directive->DumpInlineOption && (ilt() != NULL)) {
888 env()->dump_inline_data(_compile_id);
889 }
890
891 // Now that we know the size of all the monitors we can add a fixed slot
892 // for the original deopt pc.
893
894 _orig_pc_slot = fixed_slots();
895 int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
896 set_fixed_slots(next_slot);
897
898 // Compute when to use implicit null checks. Used by matching trap based
899 // nodes and NullCheck optimization.
900 set_allowed_deopt_reasons();
901
902 // Now generate code
903 Code_Gen();
904 if (failing()) return;
905
906 // Check if we want to skip execution of all compiled code.
907 {
908 #ifndef PRODUCT
909 if (OptoNoExecute) {
910 record_method_not_compilable("+OptoNoExecute"); // Flag as failed
911 return;
912 }
913 #endif
914 TracePhase tp("install_code", &timers[_t_registerMethod]);
915
916 if (is_osr_compilation()) {
917 _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
918 _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
919 } else {
920 _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
921 _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
922 }
923
924 env()->register_method(_method, _entry_bci,
925 &_code_offsets,
926 _orig_pc_slot_offset_in_bytes,
927 code_buffer(),
928 frame_size_in_words(), _oop_map_set,
929 &_handler_table, &_inc_table,
930 compiler,
931 has_unsafe_access(),
932 SharedRuntime::is_wide_vector(max_vector_size()),
933 rtm_state()
934 );
935
936 if (log() != NULL) // Print code cache state into compiler log
937 log()->code_cache_state();
938 }
939 }
940
941 //------------------------------Compile----------------------------------------
942 // Compile a runtime stub
943 Compile::Compile( ciEnv* ci_env,
944 TypeFunc_generator generator,
945 address stub_function,
946 const char *stub_name,
947 int is_fancy_jump,
948 bool pass_tls,
949 bool save_arg_registers,
950 bool return_pc,
951 DirectiveSet* directive)
952 : Phase(Compiler),
953 _env(ci_env),
954 _directive(directive),
955 _log(ci_env->log()),
956 _compile_id(0),
957 _save_argument_registers(save_arg_registers),
958 _method(NULL),
959 _stub_name(stub_name),
960 _stub_function(stub_function),
961 _stub_entry_point(NULL),
962 _entry_bci(InvocationEntryBci),
963 _initial_gvn(NULL),
964 _for_igvn(NULL),
965 _warm_calls(NULL),
966 _orig_pc_slot(0),
967 _orig_pc_slot_offset_in_bytes(0),
968 _subsume_loads(true),
969 _do_escape_analysis(false),
970 _eliminate_boxing(false),
971 _failure_reason(NULL),
972 _code_buffer("Compile::Fill_buffer"),
973 _has_method_handle_invokes(false),
974 _mach_constant_base_node(NULL),
975 _node_bundling_limit(0),
976 _node_bundling_base(NULL),
977 _java_calls(0),
978 _inner_loops(0),
979 #ifndef PRODUCT
980 _trace_opto_output(directive->TraceOptoOutputOption),
981 _in_dump_cnt(0),
982 _printer(NULL),
983 #endif
984 _comp_arena(mtCompiler),
985 _node_arena(mtCompiler),
986 _old_arena(mtCompiler),
987 _Compile_types(mtCompiler),
988 _dead_node_list(comp_arena()),
989 _dead_node_count(0),
990 _congraph(NULL),
991 _replay_inline_data(NULL),
992 _number_of_mh_late_inlines(0),
993 _inlining_progress(false),
994 _inlining_incrementally(false),
995 _print_inlining_list(NULL),
996 _print_inlining_stream(NULL),
997 _print_inlining_idx(0),
998 _print_inlining_output(NULL),
999 _allowed_reasons(0),
1000 _interpreter_frame_size(0),
1001 _max_node_limit(MaxNodeLimit),
1002 _has_reserved_stack_access(false) {
1003 C = this;
1004
1005 TraceTime t1(NULL, &_t_totalCompilation, CITime, false);
1006 TraceTime t2(NULL, &_t_stubCompilation, CITime, false);
1007
1008 #ifndef PRODUCT
1009 set_print_assembly(PrintFrameConverterAssembly);
1010 set_parsed_irreducible_loop(false);
1011 #endif
1012 set_has_irreducible_loop(false); // no loops
1013
1014 CompileWrapper cw(this);
1015 Init(/*AliasLevel=*/ 0);
1016 init_tf((*generator)());
1017
1018 {
1019 // The following is a dummy for the sake of GraphKit::gen_stub
1020 Unique_Node_List for_igvn(comp_arena());
1021 set_for_igvn(&for_igvn); // not used, but some GraphKit guys push on this
1022 PhaseGVN gvn(Thread::current()->resource_area(),255);
1023 set_initial_gvn(&gvn); // not significant, but GraphKit guys use it pervasively
1024 gvn.transform_no_reclaim(top());
1025
1026 GraphKit kit;
1027 kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
1028 }
1029
1030 NOT_PRODUCT( verify_graph_edges(); )
1031 Code_Gen();
1032 if (failing()) return;
1033
1034
1035 // Entry point will be accessed using compile->stub_entry_point();
1036 if (code_buffer() == NULL) {
1037 Matcher::soft_match_failure();
1038 } else {
1039 if (PrintAssembly && (WizardMode || Verbose))
1040 tty->print_cr("### Stub::%s", stub_name);
1041
1042 if (!failing()) {
1043 assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
1044
1045 // Make the NMethod
1046 // For now we mark the frame as never safe for profile stackwalking
1047 RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
1048 code_buffer(),
1049 CodeOffsets::frame_never_safe,
1050 // _code_offsets.value(CodeOffsets::Frame_Complete),
1051 frame_size_in_words(),
1052 _oop_map_set,
1053 save_arg_registers);
1054 assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
1055
1056 _stub_entry_point = rs->entry_point();
1057 }
1058 }
1059 }
1060
1061 //------------------------------Init-------------------------------------------
1062 // Prepare for a single compilation
1063 void Compile::Init(int aliaslevel) {
1064 _unique = 0;
1065 _regalloc = NULL;
1066
1067 _tf = NULL; // filled in later
1068 _top = NULL; // cached later
1069 _matcher = NULL; // filled in later
1070 _cfg = NULL; // filled in later
1071
1072 set_24_bit_selection_and_mode(Use24BitFP, false);
1073
1074 _node_note_array = NULL;
1075 _default_node_notes = NULL;
1076 DEBUG_ONLY( _modified_nodes = NULL; ) // Used in Optimize()
1077
1078 _immutable_memory = NULL; // filled in at first inquiry
1079
1080 // Globally visible Nodes
1081 // First set TOP to NULL to give safe behavior during creation of RootNode
1082 set_cached_top_node(NULL);
1083 set_root(new RootNode());
1084 // Now that you have a Root to point to, create the real TOP
1085 set_cached_top_node( new ConNode(Type::TOP) );
1086 set_recent_alloc(NULL, NULL);
1087
1088 // Create Debug Information Recorder to record scopes, oopmaps, etc.
1089 env()->set_oop_recorder(new OopRecorder(env()->arena()));
1090 env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
1091 env()->set_dependencies(new Dependencies(env()));
1092
1093 _fixed_slots = 0;
1094 set_has_split_ifs(false);
1095 set_has_loops(has_method() && method()->has_loops()); // first approximation
1096 set_has_stringbuilder(false);
1097 set_has_boxed_value(false);
1098 _trap_can_recompile = false; // no traps emitted yet
1099 _major_progress = true; // start out assuming good things will happen
1100 set_has_unsafe_access(false);
1101 set_max_vector_size(0);
1102 Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
1103 set_decompile_count(0);
1104
1105 set_do_freq_based_layout(_directive->BlockLayoutByFrequencyOption);
1106 set_num_loop_opts(LoopOptsCount);
1107 set_do_inlining(Inline);
1108 set_max_inline_size(MaxInlineSize);
1109 set_freq_inline_size(FreqInlineSize);
1110 set_do_scheduling(OptoScheduling);
1111 set_do_count_invocations(false);
1112 set_do_method_data_update(false);
1113
1114 set_do_vector_loop(false);
1115
1116 if (AllowVectorizeOnDemand) {
1117 if (has_method() && (_directive->VectorizeOption || _directive->VectorizeDebugOption)) {
1118 set_do_vector_loop(true);
1119 NOT_PRODUCT(if (do_vector_loop() && Verbose) {tty->print("Compile::Init: do vectorized loops (SIMD like) for method %s\n", method()->name()->as_quoted_ascii());})
1120 } else if (has_method() && method()->name() != 0 &&
1121 method()->intrinsic_id() == vmIntrinsics::_forEachRemaining) {
1122 set_do_vector_loop(true);
1123 }
1124 }
1125 set_use_cmove(UseCMoveUnconditionally /* || do_vector_loop()*/); //TODO: consider do_vector_loop() mandate use_cmove unconditionally
1126 NOT_PRODUCT(if (use_cmove() && Verbose && has_method()) {tty->print("Compile::Init: use CMove without profitability tests for method %s\n", method()->name()->as_quoted_ascii());})
1127
1128 set_age_code(has_method() && method()->profile_aging());
1129 set_rtm_state(NoRTM); // No RTM lock eliding by default
1130 _max_node_limit = _directive->MaxNodeLimitOption;
1131
1132 #if INCLUDE_RTM_OPT
1133 if (UseRTMLocking && has_method() && (method()->method_data_or_null() != NULL)) {
1134 int rtm_state = method()->method_data()->rtm_state();
1135 if (method_has_option("NoRTMLockEliding") || ((rtm_state & NoRTM) != 0)) {
1136 // Don't generate RTM lock eliding code.
1137 set_rtm_state(NoRTM);
1138 } else if (method_has_option("UseRTMLockEliding") || ((rtm_state & UseRTM) != 0) || !UseRTMDeopt) {
1139 // Generate RTM lock eliding code without abort ratio calculation code.
1140 set_rtm_state(UseRTM);
1141 } else if (UseRTMDeopt) {
1142 // Generate RTM lock eliding code and include abort ratio calculation
1143 // code if UseRTMDeopt is on.
1144 set_rtm_state(ProfileRTM);
1145 }
1146 }
1147 #endif
1148 if (debug_info()->recording_non_safepoints()) {
1149 set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
1150 (comp_arena(), 8, 0, NULL));
1151 set_default_node_notes(Node_Notes::make(this));
1152 }
1153
1154 // // -- Initialize types before each compile --
1155 // // Update cached type information
1156 // if( _method && _method->constants() )
1157 // Type::update_loaded_types(_method, _method->constants());
1158
1159 // Init alias_type map.
1160 if (!_do_escape_analysis && aliaslevel == 3)
1161 aliaslevel = 2; // No unique types without escape analysis
1162 _AliasLevel = aliaslevel;
1163 const int grow_ats = 16;
1164 _max_alias_types = grow_ats;
1165 _alias_types = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
1166 AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType, grow_ats);
1167 Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
1168 {
1169 for (int i = 0; i < grow_ats; i++) _alias_types[i] = &ats[i];
1170 }
1171 // Initialize the first few types.
1172 _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
1173 _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1174 _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1175 _num_alias_types = AliasIdxRaw+1;
1176 // Zero out the alias type cache.
1177 Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1178 // A NULL adr_type hits in the cache right away. Preload the right answer.
1179 probe_alias_cache(NULL)->_index = AliasIdxTop;
1180
1181 _intrinsics = NULL;
1182 _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1183 _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1184 _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1185 _range_check_casts = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1186 _value_type_nodes = new (comp_arena()) Unique_Node_List(comp_arena());
1187 register_library_intrinsics();
1188 }
1189
1190 //---------------------------init_start----------------------------------------
1191 // Install the StartNode on this compile object.
1192 void Compile::init_start(StartNode* s) {
1193 if (failing())
1194 return; // already failing
1195 assert(s == start(), "");
1196 }
1197
1198 /**
1199 * Return the 'StartNode'. We must not have a pending failure, since the ideal graph
1200 * can be in an inconsistent state, i.e., we can get segmentation faults when traversing
1201 * the ideal graph.
1202 */
1203 StartNode* Compile::start() const {
1204 assert (!failing(), "Must not have pending failure. Reason is: %s", failure_reason());
1205 for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1206 Node* start = root()->fast_out(i);
1207 if (start->is_Start()) {
1208 return start->as_Start();
1209 }
1210 }
1211 fatal("Did not find Start node!");
1212 return NULL;
1213 }
1214
1215 //-------------------------------immutable_memory-------------------------------------
1216 // Access immutable memory
1217 Node* Compile::immutable_memory() {
1218 if (_immutable_memory != NULL) {
1219 return _immutable_memory;
1220 }
1221 StartNode* s = start();
1222 for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1223 Node *p = s->fast_out(i);
1224 if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1225 _immutable_memory = p;
1226 return _immutable_memory;
1227 }
1228 }
1229 ShouldNotReachHere();
1230 return NULL;
1231 }
1232
1233 //----------------------set_cached_top_node------------------------------------
1234 // Install the cached top node, and make sure Node::is_top works correctly.
1235 void Compile::set_cached_top_node(Node* tn) {
1236 if (tn != NULL) verify_top(tn);
1237 Node* old_top = _top;
1238 _top = tn;
1239 // Calling Node::setup_is_top allows the nodes the chance to adjust
1240 // their _out arrays.
1241 if (_top != NULL) _top->setup_is_top();
1242 if (old_top != NULL) old_top->setup_is_top();
1243 assert(_top == NULL || top()->is_top(), "");
1244 }
1245
1246 #ifdef ASSERT
1247 uint Compile::count_live_nodes_by_graph_walk() {
1248 Unique_Node_List useful(comp_arena());
1249 // Get useful node list by walking the graph.
1250 identify_useful_nodes(useful);
1251 return useful.size();
1252 }
1253
1254 void Compile::print_missing_nodes() {
1255
1256 // Return if CompileLog is NULL and PrintIdealNodeCount is false.
1257 if ((_log == NULL) && (! PrintIdealNodeCount)) {
1258 return;
1259 }
1260
1261 // This is an expensive function. It is executed only when the user
1262 // specifies VerifyIdealNodeCount option or otherwise knows the
1263 // additional work that needs to be done to identify reachable nodes
1264 // by walking the flow graph and find the missing ones using
1265 // _dead_node_list.
1266
1267 Unique_Node_List useful(comp_arena());
1268 // Get useful node list by walking the graph.
1269 identify_useful_nodes(useful);
1270
1271 uint l_nodes = C->live_nodes();
1272 uint l_nodes_by_walk = useful.size();
1273
1274 if (l_nodes != l_nodes_by_walk) {
1275 if (_log != NULL) {
1276 _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
1277 _log->stamp();
1278 _log->end_head();
1279 }
1280 VectorSet& useful_member_set = useful.member_set();
1281 int last_idx = l_nodes_by_walk;
1282 for (int i = 0; i < last_idx; i++) {
1283 if (useful_member_set.test(i)) {
1284 if (_dead_node_list.test(i)) {
1285 if (_log != NULL) {
1286 _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
1287 }
1288 if (PrintIdealNodeCount) {
1289 // Print the log message to tty
1290 tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
1291 useful.at(i)->dump();
1292 }
1293 }
1294 }
1295 else if (! _dead_node_list.test(i)) {
1296 if (_log != NULL) {
1297 _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
1298 }
1299 if (PrintIdealNodeCount) {
1300 // Print the log message to tty
1301 tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
1302 }
1303 }
1304 }
1305 if (_log != NULL) {
1306 _log->tail("mismatched_nodes");
1307 }
1308 }
1309 }
1310 void Compile::record_modified_node(Node* n) {
1311 if (_modified_nodes != NULL && !_inlining_incrementally &&
1312 n->outcnt() != 0 && !n->is_Con()) {
1313 _modified_nodes->push(n);
1314 }
1315 }
1316
1317 void Compile::remove_modified_node(Node* n) {
1318 if (_modified_nodes != NULL) {
1319 _modified_nodes->remove(n);
1320 }
1321 }
1322 #endif
1323
1324 #ifndef PRODUCT
1325 void Compile::verify_top(Node* tn) const {
1326 if (tn != NULL) {
1327 assert(tn->is_Con(), "top node must be a constant");
1328 assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1329 assert(tn->in(0) != NULL, "must have live top node");
1330 }
1331 }
1332 #endif
1333
1334
1335 ///-------------------Managing Per-Node Debug & Profile Info-------------------
1336
1337 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1338 guarantee(arr != NULL, "");
1339 int num_blocks = arr->length();
1340 if (grow_by < num_blocks) grow_by = num_blocks;
1341 int num_notes = grow_by * _node_notes_block_size;
1342 Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1343 Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1344 while (num_notes > 0) {
1345 arr->append(notes);
1346 notes += _node_notes_block_size;
1347 num_notes -= _node_notes_block_size;
1348 }
1349 assert(num_notes == 0, "exact multiple, please");
1350 }
1351
1352 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1353 if (source == NULL || dest == NULL) return false;
1354
1355 if (dest->is_Con())
1356 return false; // Do not push debug info onto constants.
1357
1358 #ifdef ASSERT
1359 // Leave a bread crumb trail pointing to the original node:
1360 if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
1361 dest->set_debug_orig(source);
1362 }
1363 #endif
1364
1365 if (node_note_array() == NULL)
1366 return false; // Not collecting any notes now.
1367
1368 // This is a copy onto a pre-existing node, which may already have notes.
1369 // If both nodes have notes, do not overwrite any pre-existing notes.
1370 Node_Notes* source_notes = node_notes_at(source->_idx);
1371 if (source_notes == NULL || source_notes->is_clear()) return false;
1372 Node_Notes* dest_notes = node_notes_at(dest->_idx);
1373 if (dest_notes == NULL || dest_notes->is_clear()) {
1374 return set_node_notes_at(dest->_idx, source_notes);
1375 }
1376
1377 Node_Notes merged_notes = (*source_notes);
1378 // The order of operations here ensures that dest notes will win...
1379 merged_notes.update_from(dest_notes);
1380 return set_node_notes_at(dest->_idx, &merged_notes);
1381 }
1382
1383
1384 //--------------------------allow_range_check_smearing-------------------------
1385 // Gating condition for coalescing similar range checks.
1386 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1387 // single covering check that is at least as strong as any of them.
1388 // If the optimization succeeds, the simplified (strengthened) range check
1389 // will always succeed. If it fails, we will deopt, and then give up
1390 // on the optimization.
1391 bool Compile::allow_range_check_smearing() const {
1392 // If this method has already thrown a range-check,
1393 // assume it was because we already tried range smearing
1394 // and it failed.
1395 uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1396 return !already_trapped;
1397 }
1398
1399
1400 //------------------------------flatten_alias_type-----------------------------
1401 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1402 int offset = tj->offset();
1403 TypePtr::PTR ptr = tj->ptr();
1404
1405 // Known instance (scalarizable allocation) alias only with itself.
1406 bool is_known_inst = tj->isa_oopptr() != NULL &&
1407 tj->is_oopptr()->is_known_instance();
1408
1409 // Process weird unsafe references.
1410 if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1411 assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
1412 assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1413 tj = TypeOopPtr::BOTTOM;
1414 ptr = tj->ptr();
1415 offset = tj->offset();
1416 }
1417
1418 // Array pointers need some flattening
1419 const TypeAryPtr *ta = tj->isa_aryptr();
1420 if (ta && ta->is_stable()) {
1421 // Erase stability property for alias analysis.
1422 tj = ta = ta->cast_to_stable(false);
1423 }
1424 if( ta && is_known_inst ) {
1425 if ( offset != Type::OffsetBot &&
1426 offset > arrayOopDesc::length_offset_in_bytes() ) {
1427 offset = Type::OffsetBot; // Flatten constant access into array body only
1428 tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, Type::Offset(offset), ta->field_offset(), ta->instance_id());
1429 }
1430 } else if( ta && _AliasLevel >= 2 ) {
1431 // For arrays indexed by constant indices, we flatten the alias
1432 // space to include all of the array body. Only the header, klass
1433 // and array length can be accessed un-aliased.
1434 // For flattened value type array, each field has its own slice so
1435 // we must include the field offset.
1436 if( offset != Type::OffsetBot ) {
1437 if( ta->const_oop() ) { // MethodData* or Method*
1438 offset = Type::OffsetBot; // Flatten constant access into array body
1439 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,Type::Offset(offset), ta->field_offset());
1440 } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1441 // range is OK as-is.
1442 tj = ta = TypeAryPtr::RANGE;
1443 } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1444 tj = TypeInstPtr::KLASS; // all klass loads look alike
1445 ta = TypeAryPtr::RANGE; // generic ignored junk
1446 ptr = TypePtr::BotPTR;
1447 } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1448 tj = TypeInstPtr::MARK;
1449 ta = TypeAryPtr::RANGE; // generic ignored junk
1450 ptr = TypePtr::BotPTR;
1451 } else { // Random constant offset into array body
1452 offset = Type::OffsetBot; // Flatten constant access into array body
1453 tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,Type::Offset(offset), ta->field_offset());
1454 }
1455 }
1456 // Arrays of fixed size alias with arrays of unknown size.
1457 if (ta->size() != TypeInt::POS) {
1458 const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1459 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,Type::Offset(offset), ta->field_offset());
1460 }
1461 // Arrays of known objects become arrays of unknown objects.
1462 if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1463 const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1464 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,Type::Offset(offset), ta->field_offset());
1465 }
1466 if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1467 const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1468 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,Type::Offset(offset), ta->field_offset());
1469 }
1470 // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1471 // cannot be distinguished by bytecode alone.
1472 if (ta->elem() == TypeInt::BOOL) {
1473 const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1474 ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1475 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,Type::Offset(offset), ta->field_offset());
1476 }
1477 // During the 2nd round of IterGVN, NotNull castings are removed.
1478 // Make sure the Bottom and NotNull variants alias the same.
1479 // Also, make sure exact and non-exact variants alias the same.
1480 if (ptr == TypePtr::NotNull || ta->klass_is_exact() || ta->speculative() != NULL) {
1481 tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,Type::Offset(offset), ta->field_offset());
1482 }
1483 }
1484
1485 // Oop pointers need some flattening
1486 const TypeInstPtr *to = tj->isa_instptr();
1487 if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
1488 ciInstanceKlass *k = to->klass()->as_instance_klass();
1489 if( ptr == TypePtr::Constant ) {
1490 if (to->klass() != ciEnv::current()->Class_klass() ||
1491 offset < k->size_helper() * wordSize) {
1492 // No constant oop pointers (such as Strings); they alias with
1493 // unknown strings.
1494 assert(!is_known_inst, "not scalarizable allocation");
1495 tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,Type::Offset(offset));
1496 }
1497 } else if( is_known_inst ) {
1498 tj = to; // Keep NotNull and klass_is_exact for instance type
1499 } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1500 // During the 2nd round of IterGVN, NotNull castings are removed.
1501 // Make sure the Bottom and NotNull variants alias the same.
1502 // Also, make sure exact and non-exact variants alias the same.
1503 tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,Type::Offset(offset));
1504 }
1505 if (to->speculative() != NULL) {
1506 tj = to = TypeInstPtr::make(to->ptr(),to->klass(),to->klass_is_exact(),to->const_oop(),Type::Offset(to->offset()), to->instance_id());
1507 }
1508 // Canonicalize the holder of this field
1509 if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1510 // First handle header references such as a LoadKlassNode, even if the
1511 // object's klass is unloaded at compile time (4965979).
1512 if (!is_known_inst) { // Do it only for non-instance types
1513 tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, Type::Offset(offset));
1514 }
1515 } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
1516 // Static fields are in the space above the normal instance
1517 // fields in the java.lang.Class instance.
1518 if (to->klass() != ciEnv::current()->Class_klass()) {
1519 to = NULL;
1520 tj = TypeOopPtr::BOTTOM;
1521 offset = tj->offset();
1522 }
1523 } else {
1524 ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
1525 if (!k->equals(canonical_holder) || tj->offset() != offset) {
1526 if( is_known_inst ) {
1527 tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, Type::Offset(offset), to->instance_id());
1528 } else {
1529 tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, Type::Offset(offset));
1530 }
1531 }
1532 }
1533 }
1534
1535 // Klass pointers to object array klasses need some flattening
1536 const TypeKlassPtr *tk = tj->isa_klassptr();
1537 if( tk ) {
1538 // If we are referencing a field within a Klass, we need
1539 // to assume the worst case of an Object. Both exact and
1540 // inexact types must flatten to the same alias class so
1541 // use NotNull as the PTR.
1542 if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1543
1544 tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
1545 TypeKlassPtr::OBJECT->klass(),
1546 Type::Offset(offset));
1547 }
1548
1549 ciKlass* klass = tk->klass();
1550 if (klass != NULL && klass->is_obj_array_klass()) {
1551 ciKlass* k = TypeAryPtr::OOPS->klass();
1552 if( !k || !k->is_loaded() ) // Only fails for some -Xcomp runs
1553 k = TypeInstPtr::BOTTOM->klass();
1554 tj = tk = TypeKlassPtr::make(TypePtr::NotNull, k, Type::Offset(offset));
1555 }
1556
1557 // Check for precise loads from the primary supertype array and force them
1558 // to the supertype cache alias index. Check for generic array loads from
1559 // the primary supertype array and also force them to the supertype cache
1560 // alias index. Since the same load can reach both, we need to merge
1561 // these 2 disparate memories into the same alias class. Since the
1562 // primary supertype array is read-only, there's no chance of confusion
1563 // where we bypass an array load and an array store.
1564 int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
1565 if (offset == Type::OffsetBot ||
1566 (offset >= primary_supers_offset &&
1567 offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
1568 offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
1569 offset = in_bytes(Klass::secondary_super_cache_offset());
1570 tj = tk = TypeKlassPtr::make(TypePtr::NotNull, tk->klass(), Type::Offset(offset));
1571 }
1572 }
1573
1574 // Flatten all Raw pointers together.
1575 if (tj->base() == Type::RawPtr)
1576 tj = TypeRawPtr::BOTTOM;
1577
1578 if (tj->base() == Type::AnyPtr)
1579 tj = TypePtr::BOTTOM; // An error, which the caller must check for.
1580
1581 // Flatten all to bottom for now
1582 switch( _AliasLevel ) {
1583 case 0:
1584 tj = TypePtr::BOTTOM;
1585 break;
1586 case 1: // Flatten to: oop, static, field or array
1587 switch (tj->base()) {
1588 //case Type::AryPtr: tj = TypeAryPtr::RANGE; break;
1589 case Type::RawPtr: tj = TypeRawPtr::BOTTOM; break;
1590 case Type::AryPtr: // do not distinguish arrays at all
1591 case Type::InstPtr: tj = TypeInstPtr::BOTTOM; break;
1592 case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
1593 case Type::AnyPtr: tj = TypePtr::BOTTOM; break; // caller checks it
1594 default: ShouldNotReachHere();
1595 }
1596 break;
1597 case 2: // No collapsing at level 2; keep all splits
1598 case 3: // No collapsing at level 3; keep all splits
1599 break;
1600 default:
1601 Unimplemented();
1602 }
1603
1604 offset = tj->offset();
1605 assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1606
1607 assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1608 (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1609 (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1610 (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1611 (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1612 (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1613 (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr) ,
1614 "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1615 assert( tj->ptr() != TypePtr::TopPTR &&
1616 tj->ptr() != TypePtr::AnyNull &&
1617 tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1618 // assert( tj->ptr() != TypePtr::Constant ||
1619 // tj->base() == Type::RawPtr ||
1620 // tj->base() == Type::KlassPtr, "No constant oop addresses" );
1621
1622 return tj;
1623 }
1624
1625 void Compile::AliasType::Init(int i, const TypePtr* at) {
1626 _index = i;
1627 _adr_type = at;
1628 _field = NULL;
1629 _element = NULL;
1630 _is_rewritable = true; // default
1631 const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
1632 if (atoop != NULL && atoop->is_known_instance()) {
1633 const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1634 _general_index = Compile::current()->get_alias_index(gt);
1635 } else {
1636 _general_index = 0;
1637 }
1638 }
1639
1640 BasicType Compile::AliasType::basic_type() const {
1641 if (element() != NULL) {
1642 const Type* element = adr_type()->is_aryptr()->elem();
1643 return element->isa_narrowoop() ? T_OBJECT : element->array_element_basic_type();
1644 } if (field() != NULL) {
1645 return field()->layout_type();
1646 } else {
1647 return T_ILLEGAL; // unknown
1648 }
1649 }
1650
1651 //---------------------------------print_on------------------------------------
1652 #ifndef PRODUCT
1653 void Compile::AliasType::print_on(outputStream* st) {
1654 if (index() < 10)
1655 st->print("@ <%d> ", index());
1656 else st->print("@ <%d>", index());
1657 st->print(is_rewritable() ? " " : " RO");
1658 int offset = adr_type()->offset();
1659 if (offset == Type::OffsetBot)
1660 st->print(" +any");
1661 else st->print(" +%-3d", offset);
1662 st->print(" in ");
1663 adr_type()->dump_on(st);
1664 const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1665 if (field() != NULL && tjp) {
1666 if (tjp->klass() != field()->holder() ||
1667 tjp->offset() != field()->offset_in_bytes()) {
1668 st->print(" != ");
1669 field()->print();
1670 st->print(" ***");
1671 }
1672 }
1673 }
1674
1675 void print_alias_types() {
1676 Compile* C = Compile::current();
1677 tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1678 for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1679 C->alias_type(idx)->print_on(tty);
1680 tty->cr();
1681 }
1682 }
1683 #endif
1684
1685
1686 //----------------------------probe_alias_cache--------------------------------
1687 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1688 intptr_t key = (intptr_t) adr_type;
1689 key ^= key >> logAliasCacheSize;
1690 return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1691 }
1692
1693
1694 //-----------------------------grow_alias_types--------------------------------
1695 void Compile::grow_alias_types() {
1696 const int old_ats = _max_alias_types; // how many before?
1697 const int new_ats = old_ats; // how many more?
1698 const int grow_ats = old_ats+new_ats; // how many now?
1699 _max_alias_types = grow_ats;
1700 _alias_types = REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1701 AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1702 Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1703 for (int i = 0; i < new_ats; i++) _alias_types[old_ats+i] = &ats[i];
1704 }
1705
1706
1707 //--------------------------------find_alias_type------------------------------
1708 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1709 if (_AliasLevel == 0)
1710 return alias_type(AliasIdxBot);
1711
1712 AliasCacheEntry* ace = probe_alias_cache(adr_type);
1713 if (ace->_adr_type == adr_type) {
1714 return alias_type(ace->_index);
1715 }
1716
1717 // Handle special cases.
1718 if (adr_type == NULL) return alias_type(AliasIdxTop);
1719 if (adr_type == TypePtr::BOTTOM) return alias_type(AliasIdxBot);
1720
1721 // Do it the slow way.
1722 const TypePtr* flat = flatten_alias_type(adr_type);
1723
1724 #ifdef ASSERT
1725 {
1726 ResourceMark rm;
1727 assert(flat == flatten_alias_type(flat), "not idempotent: adr_type = %s; flat = %s => %s",
1728 Type::str(adr_type), Type::str(flat), Type::str(flatten_alias_type(flat)));
1729 assert(flat != TypePtr::BOTTOM, "cannot alias-analyze an untyped ptr: adr_type = %s",
1730 Type::str(adr_type));
1731 if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1732 const TypeOopPtr* foop = flat->is_oopptr();
1733 // Scalarizable allocations have exact klass always.
1734 bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1735 const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1736 assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type: foop = %s; xoop = %s",
1737 Type::str(foop), Type::str(xoop));
1738 }
1739 }
1740 #endif
1741
1742 int idx = AliasIdxTop;
1743 for (int i = 0; i < num_alias_types(); i++) {
1744 if (alias_type(i)->adr_type() == flat) {
1745 idx = i;
1746 break;
1747 }
1748 }
1749
1750 if (idx == AliasIdxTop) {
1751 if (no_create) return NULL;
1752 // Grow the array if necessary.
1753 if (_num_alias_types == _max_alias_types) grow_alias_types();
1754 // Add a new alias type.
1755 idx = _num_alias_types++;
1756 _alias_types[idx]->Init(idx, flat);
1757 if (flat == TypeInstPtr::KLASS) alias_type(idx)->set_rewritable(false);
1758 if (flat == TypeAryPtr::RANGE) alias_type(idx)->set_rewritable(false);
1759 if (flat->isa_instptr()) {
1760 if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
1761 && flat->is_instptr()->klass() == env()->Class_klass())
1762 alias_type(idx)->set_rewritable(false);
1763 }
1764 if (flat->isa_aryptr()) {
1765 #ifdef ASSERT
1766 const int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1767 // (T_BYTE has the weakest alignment and size restrictions...)
1768 assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
1769 #endif
1770 if (flat->offset() == TypePtr::OffsetBot) {
1771 alias_type(idx)->set_element(flat->is_aryptr()->elem());
1772 }
1773 }
1774 if (flat->isa_klassptr()) {
1775 if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
1776 alias_type(idx)->set_rewritable(false);
1777 if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
1778 alias_type(idx)->set_rewritable(false);
1779 if (flat->offset() == in_bytes(Klass::access_flags_offset()))
1780 alias_type(idx)->set_rewritable(false);
1781 if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
1782 alias_type(idx)->set_rewritable(false);
1783 }
1784 // %%% (We would like to finalize JavaThread::threadObj_offset(),
1785 // but the base pointer type is not distinctive enough to identify
1786 // references into JavaThread.)
1787
1788 // Check for final fields.
1789 const TypeInstPtr* tinst = flat->isa_instptr();
1790 const TypeValueTypePtr* vtptr = flat->isa_valuetypeptr();
1791 ciField* field = NULL;
1792 if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1793 if (tinst->const_oop() != NULL &&
1794 tinst->klass() == ciEnv::current()->Class_klass() &&
1795 tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
1796 // static field
1797 ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1798 field = k->get_field_by_offset(tinst->offset(), true);
1799 } else {
1800 ciInstanceKlass *k = tinst->klass()->as_instance_klass();
1801 field = k->get_field_by_offset(tinst->offset(), false);
1802 }
1803 } else if (vtptr) {
1804 // Value type field
1805 ciValueKlass* vk = vtptr->klass()->as_value_klass();
1806 field = vk->get_field_by_offset(vtptr->offset(), false);
1807 }
1808 assert(field == NULL ||
1809 original_field == NULL ||
1810 (field->holder() == original_field->holder() &&
1811 field->offset() == original_field->offset() &&
1812 field->is_static() == original_field->is_static()), "wrong field?");
1813 // Set field() and is_rewritable() attributes.
1814 if (field != NULL) alias_type(idx)->set_field(field);
1815 }
1816
1817 // Fill the cache for next time.
1818 ace->_adr_type = adr_type;
1819 ace->_index = idx;
1820 assert(alias_type(adr_type) == alias_type(idx), "type must be installed");
1821
1822 // Might as well try to fill the cache for the flattened version, too.
1823 AliasCacheEntry* face = probe_alias_cache(flat);
1824 if (face->_adr_type == NULL) {
1825 face->_adr_type = flat;
1826 face->_index = idx;
1827 assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1828 }
1829
1830 return alias_type(idx);
1831 }
1832
1833
1834 Compile::AliasType* Compile::alias_type(ciField* field) {
1835 const TypeOopPtr* t;
1836 if (field->is_static())
1837 t = TypeInstPtr::make(field->holder()->java_mirror());
1838 else
1839 t = TypeOopPtr::make_from_klass_raw(field->holder());
1840 AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1841 assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
1842 return atp;
1843 }
1844
1845
1846 //------------------------------have_alias_type--------------------------------
1847 bool Compile::have_alias_type(const TypePtr* adr_type) {
1848 AliasCacheEntry* ace = probe_alias_cache(adr_type);
1849 if (ace->_adr_type == adr_type) {
1850 return true;
1851 }
1852
1853 // Handle special cases.
1854 if (adr_type == NULL) return true;
1855 if (adr_type == TypePtr::BOTTOM) return true;
1856
1857 return find_alias_type(adr_type, true, NULL) != NULL;
1858 }
1859
1860 //-----------------------------must_alias--------------------------------------
1861 // True if all values of the given address type are in the given alias category.
1862 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1863 if (alias_idx == AliasIdxBot) return true; // the universal category
1864 if (adr_type == NULL) return true; // NULL serves as TypePtr::TOP
1865 if (alias_idx == AliasIdxTop) return false; // the empty category
1866 if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1867
1868 // the only remaining possible overlap is identity
1869 int adr_idx = get_alias_index(adr_type);
1870 assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1871 assert(adr_idx == alias_idx ||
1872 (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1873 && adr_type != TypeOopPtr::BOTTOM),
1874 "should not be testing for overlap with an unsafe pointer");
1875 return adr_idx == alias_idx;
1876 }
1877
1878 //------------------------------can_alias--------------------------------------
1879 // True if any values of the given address type are in the given alias category.
1880 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1881 if (alias_idx == AliasIdxTop) return false; // the empty category
1882 if (adr_type == NULL) return false; // NULL serves as TypePtr::TOP
1883 if (alias_idx == AliasIdxBot) return true; // the universal category
1884 if (adr_type->base() == Type::AnyPtr) return true; // TypePtr::BOTTOM or its twins
1885
1886 // the only remaining possible overlap is identity
1887 int adr_idx = get_alias_index(adr_type);
1888 assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1889 return adr_idx == alias_idx;
1890 }
1891
1892
1893
1894 //---------------------------pop_warm_call-------------------------------------
1895 WarmCallInfo* Compile::pop_warm_call() {
1896 WarmCallInfo* wci = _warm_calls;
1897 if (wci != NULL) _warm_calls = wci->remove_from(wci);
1898 return wci;
1899 }
1900
1901 //----------------------------Inline_Warm--------------------------------------
1902 int Compile::Inline_Warm() {
1903 // If there is room, try to inline some more warm call sites.
1904 // %%% Do a graph index compaction pass when we think we're out of space?
1905 if (!InlineWarmCalls) return 0;
1906
1907 int calls_made_hot = 0;
1908 int room_to_grow = NodeCountInliningCutoff - unique();
1909 int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
1910 int amount_grown = 0;
1911 WarmCallInfo* call;
1912 while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
1913 int est_size = (int)call->size();
1914 if (est_size > (room_to_grow - amount_grown)) {
1915 // This one won't fit anyway. Get rid of it.
1916 call->make_cold();
1917 continue;
1918 }
1919 call->make_hot();
1920 calls_made_hot++;
1921 amount_grown += est_size;
1922 amount_to_grow -= est_size;
1923 }
1924
1925 if (calls_made_hot > 0) set_major_progress();
1926 return calls_made_hot;
1927 }
1928
1929
1930 //----------------------------Finish_Warm--------------------------------------
1931 void Compile::Finish_Warm() {
1932 if (!InlineWarmCalls) return;
1933 if (failing()) return;
1934 if (warm_calls() == NULL) return;
1935
1936 // Clean up loose ends, if we are out of space for inlining.
1937 WarmCallInfo* call;
1938 while ((call = pop_warm_call()) != NULL) {
1939 call->make_cold();
1940 }
1941 }
1942
1943 //---------------------cleanup_loop_predicates-----------------------
1944 // Remove the opaque nodes that protect the predicates so that all unused
1945 // checks and uncommon_traps will be eliminated from the ideal graph
1946 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
1947 if (predicate_count()==0) return;
1948 for (int i = predicate_count(); i > 0; i--) {
1949 Node * n = predicate_opaque1_node(i-1);
1950 assert(n->Opcode() == Op_Opaque1, "must be");
1951 igvn.replace_node(n, n->in(1));
1952 }
1953 assert(predicate_count()==0, "should be clean!");
1954 }
1955
1956 void Compile::add_range_check_cast(Node* n) {
1957 assert(n->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1958 assert(!_range_check_casts->contains(n), "duplicate entry in range check casts");
1959 _range_check_casts->append(n);
1960 }
1961
1962 // Remove all range check dependent CastIINodes.
1963 void Compile::remove_range_check_casts(PhaseIterGVN &igvn) {
1964 for (int i = range_check_cast_count(); i > 0; i--) {
1965 Node* cast = range_check_cast_node(i-1);
1966 assert(cast->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1967 igvn.replace_node(cast, cast->in(1));
1968 }
1969 assert(range_check_cast_count() == 0, "should be empty");
1970 }
1971
1972 void Compile::add_value_type(Node* n) {
1973 assert(n->is_ValueTypeBase(), "unexpected node");
1974 if (_value_type_nodes != NULL) {
1975 _value_type_nodes->push(n);
1976 }
1977 }
1978
1979 void Compile::remove_value_type(Node* n) {
1980 assert(n->is_ValueTypeBase(), "unexpected node");
1981 if (_value_type_nodes != NULL) {
1982 _value_type_nodes->remove(n);
1983 }
1984 }
1985
1986 void Compile::process_value_types(PhaseIterGVN &igvn) {
1987 // Make value types scalar in safepoints
1988 while (_value_type_nodes->size() != 0) {
1989 ValueTypeBaseNode* vt = _value_type_nodes->pop()->as_ValueTypeBase();
1990 vt->make_scalar_in_safepoints(igvn.C->root(), &igvn);
1991 if (vt->is_ValueTypePtr()) {
1992 igvn.replace_node(vt, vt->get_oop());
1993 }
1994 }
1995 _value_type_nodes = NULL;
1996 igvn.optimize();
1997 }
1998
1999 // StringOpts and late inlining of string methods
2000 void Compile::inline_string_calls(bool parse_time) {
2001 {
2002 // remove useless nodes to make the usage analysis simpler
2003 ResourceMark rm;
2004 PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2005 }
2006
2007 {
2008 ResourceMark rm;
2009 print_method(PHASE_BEFORE_STRINGOPTS, 3);
2010 PhaseStringOpts pso(initial_gvn(), for_igvn());
2011 print_method(PHASE_AFTER_STRINGOPTS, 3);
2012 }
2013
2014 // now inline anything that we skipped the first time around
2015 if (!parse_time) {
2016 _late_inlines_pos = _late_inlines.length();
2017 }
2018
2019 while (_string_late_inlines.length() > 0) {
2020 CallGenerator* cg = _string_late_inlines.pop();
2021 cg->do_late_inline();
2022 if (failing()) return;
2023 }
2024 _string_late_inlines.trunc_to(0);
2025 }
2026
2027 // Late inlining of boxing methods
2028 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
2029 if (_boxing_late_inlines.length() > 0) {
2030 assert(has_boxed_value(), "inconsistent");
2031
2032 PhaseGVN* gvn = initial_gvn();
2033 set_inlining_incrementally(true);
2034
2035 assert( igvn._worklist.size() == 0, "should be done with igvn" );
2036 for_igvn()->clear();
2037 gvn->replace_with(&igvn);
2038
2039 _late_inlines_pos = _late_inlines.length();
2040
2041 while (_boxing_late_inlines.length() > 0) {
2042 CallGenerator* cg = _boxing_late_inlines.pop();
2043 cg->do_late_inline();
2044 if (failing()) return;
2045 }
2046 _boxing_late_inlines.trunc_to(0);
2047
2048 {
2049 ResourceMark rm;
2050 PhaseRemoveUseless pru(gvn, for_igvn());
2051 }
2052
2053 igvn = PhaseIterGVN(gvn);
2054 igvn.optimize();
2055
2056 set_inlining_progress(false);
2057 set_inlining_incrementally(false);
2058 }
2059 }
2060
2061 void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
2062 assert(IncrementalInline, "incremental inlining should be on");
2063 PhaseGVN* gvn = initial_gvn();
2064
2065 set_inlining_progress(false);
2066 for_igvn()->clear();
2067 gvn->replace_with(&igvn);
2068
2069 {
2070 TracePhase tp("incrementalInline_inline", &timers[_t_incrInline_inline]);
2071 int i = 0;
2072 for (; i <_late_inlines.length() && !inlining_progress(); i++) {
2073 CallGenerator* cg = _late_inlines.at(i);
2074 _late_inlines_pos = i+1;
2075 cg->do_late_inline();
2076 if (failing()) return;
2077 }
2078 int j = 0;
2079 for (; i < _late_inlines.length(); i++, j++) {
2080 _late_inlines.at_put(j, _late_inlines.at(i));
2081 }
2082 _late_inlines.trunc_to(j);
2083 }
2084
2085 {
2086 TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
2087 ResourceMark rm;
2088 PhaseRemoveUseless pru(gvn, for_igvn());
2089 }
2090
2091 {
2092 TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2093 igvn = PhaseIterGVN(gvn);
2094 }
2095 }
2096
2097 // Perform incremental inlining until bound on number of live nodes is reached
2098 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
2099 TracePhase tp("incrementalInline", &timers[_t_incrInline]);
2100
2101 PhaseGVN* gvn = initial_gvn();
2102
2103 set_inlining_incrementally(true);
2104 set_inlining_progress(true);
2105 uint low_live_nodes = 0;
2106
2107 while(inlining_progress() && _late_inlines.length() > 0) {
2108
2109 if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2110 if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
2111 TracePhase tp("incrementalInline_ideal", &timers[_t_incrInline_ideal]);
2112 // PhaseIdealLoop is expensive so we only try it once we are
2113 // out of live nodes and we only try it again if the previous
2114 // helped got the number of nodes down significantly
2115 PhaseIdealLoop ideal_loop( igvn, false, true );
2116 if (failing()) return;
2117 low_live_nodes = live_nodes();
2118 _major_progress = true;
2119 }
2120
2121 if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2122 break;
2123 }
2124 }
2125
2126 inline_incrementally_one(igvn);
2127
2128 if (failing()) return;
2129
2130 {
2131 TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2132 igvn.optimize();
2133 }
2134
2135 if (failing()) return;
2136 }
2137
2138 assert( igvn._worklist.size() == 0, "should be done with igvn" );
2139
2140 if (_string_late_inlines.length() > 0) {
2141 assert(has_stringbuilder(), "inconsistent");
2142 for_igvn()->clear();
2143 initial_gvn()->replace_with(&igvn);
2144
2145 inline_string_calls(false);
2146
2147 if (failing()) return;
2148
2149 {
2150 TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
2151 ResourceMark rm;
2152 PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2153 }
2154
2155 {
2156 TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2157 igvn = PhaseIterGVN(gvn);
2158 igvn.optimize();
2159 }
2160 }
2161
2162 set_inlining_incrementally(false);
2163 }
2164
2165
2166 //------------------------------Optimize---------------------------------------
2167 // Given a graph, optimize it.
2168 void Compile::Optimize() {
2169 TracePhase tp("optimizer", &timers[_t_optimizer]);
2170
2171 #ifndef PRODUCT
2172 if (_directive->BreakAtCompileOption) {
2173 BREAKPOINT;
2174 }
2175
2176 #endif
2177
2178 ResourceMark rm;
2179 int loop_opts_cnt;
2180
2181 print_inlining_reinit();
2182
2183 NOT_PRODUCT( verify_graph_edges(); )
2184
2185 print_method(PHASE_AFTER_PARSING);
2186
2187 {
2188 // Iterative Global Value Numbering, including ideal transforms
2189 // Initialize IterGVN with types and values from parse-time GVN
2190 PhaseIterGVN igvn(initial_gvn());
2191 #ifdef ASSERT
2192 _modified_nodes = new (comp_arena()) Unique_Node_List(comp_arena());
2193 #endif
2194 {
2195 TracePhase tp("iterGVN", &timers[_t_iterGVN]);
2196 igvn.optimize();
2197 }
2198
2199 print_method(PHASE_ITER_GVN1, 2);
2200
2201 if (failing()) return;
2202
2203 inline_incrementally(igvn);
2204
2205 print_method(PHASE_INCREMENTAL_INLINE, 2);
2206
2207 if (failing()) return;
2208
2209 if (eliminate_boxing()) {
2210 // Inline valueOf() methods now.
2211 inline_boxing_calls(igvn);
2212
2213 if (AlwaysIncrementalInline) {
2214 inline_incrementally(igvn);
2215 }
2216
2217 print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
2218
2219 if (failing()) return;
2220 }
2221
2222 // Remove the speculative part of types and clean up the graph from
2223 // the extra CastPP nodes whose only purpose is to carry them. Do
2224 // that early so that optimizations are not disrupted by the extra
2225 // CastPP nodes.
2226 remove_speculative_types(igvn);
2227
2228 // No more new expensive nodes will be added to the list from here
2229 // so keep only the actual candidates for optimizations.
2230 cleanup_expensive_nodes(igvn);
2231
2232 if (!failing() && RenumberLiveNodes && live_nodes() + NodeLimitFudgeFactor < unique()) {
2233 Compile::TracePhase tp("", &timers[_t_renumberLive]);
2234 initial_gvn()->replace_with(&igvn);
2235 for_igvn()->clear();
2236 Unique_Node_List new_worklist(C->comp_arena());
2237 {
2238 ResourceMark rm;
2239 PhaseRenumberLive prl = PhaseRenumberLive(initial_gvn(), for_igvn(), &new_worklist);
2240 }
2241 set_for_igvn(&new_worklist);
2242 igvn = PhaseIterGVN(initial_gvn());
2243 igvn.optimize();
2244 }
2245
2246 if (_value_type_nodes->size() > 0) {
2247 // Do this once all inlining is over to avoid getting inconsistent debug info
2248 process_value_types(igvn);
2249 }
2250
2251 // Perform escape analysis
2252 if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
2253 if (has_loops()) {
2254 // Cleanup graph (remove dead nodes).
2255 TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2256 PhaseIdealLoop ideal_loop( igvn, false, true );
2257 if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
2258 if (failing()) return;
2259 }
2260 ConnectionGraph::do_analysis(this, &igvn);
2261
2262 if (failing()) return;
2263
2264 // Optimize out fields loads from scalar replaceable allocations.
2265 igvn.optimize();
2266 print_method(PHASE_ITER_GVN_AFTER_EA, 2);
2267
2268 if (failing()) return;
2269
2270 if (congraph() != NULL && macro_count() > 0) {
2271 TracePhase tp("macroEliminate", &timers[_t_macroEliminate]);
2272 PhaseMacroExpand mexp(igvn);
2273 mexp.eliminate_macro_nodes();
2274 igvn.set_delay_transform(false);
2275
2276 igvn.optimize();
2277 print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
2278
2279 if (failing()) return;
2280 }
2281 }
2282
2283 // Loop transforms on the ideal graph. Range Check Elimination,
2284 // peeling, unrolling, etc.
2285
2286 // Set loop opts counter
2287 loop_opts_cnt = num_loop_opts();
2288 if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
2289 {
2290 TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2291 PhaseIdealLoop ideal_loop( igvn, true );
2292 loop_opts_cnt--;
2293 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
2294 if (failing()) return;
2295 }
2296 // Loop opts pass if partial peeling occurred in previous pass
2297 if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
2298 TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2299 PhaseIdealLoop ideal_loop( igvn, false );
2300 loop_opts_cnt--;
2301 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
2302 if (failing()) return;
2303 }
2304 // Loop opts pass for loop-unrolling before CCP
2305 if(major_progress() && (loop_opts_cnt > 0)) {
2306 TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2307 PhaseIdealLoop ideal_loop( igvn, false );
2308 loop_opts_cnt--;
2309 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
2310 }
2311 if (!failing()) {
2312 // Verify that last round of loop opts produced a valid graph
2313 TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2314 PhaseIdealLoop::verify(igvn);
2315 }
2316 }
2317 if (failing()) return;
2318
2319 // Conditional Constant Propagation;
2320 PhaseCCP ccp( &igvn );
2321 assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
2322 {
2323 TracePhase tp("ccp", &timers[_t_ccp]);
2324 ccp.do_transform();
2325 }
2326 print_method(PHASE_CPP1, 2);
2327
2328 assert( true, "Break here to ccp.dump_old2new_map()");
2329
2330 // Iterative Global Value Numbering, including ideal transforms
2331 {
2332 TracePhase tp("iterGVN2", &timers[_t_iterGVN2]);
2333 igvn = ccp;
2334 igvn.optimize();
2335 }
2336
2337 print_method(PHASE_ITER_GVN2, 2);
2338
2339 if (failing()) return;
2340
2341 // Loop transforms on the ideal graph. Range Check Elimination,
2342 // peeling, unrolling, etc.
2343 if(loop_opts_cnt > 0) {
2344 debug_only( int cnt = 0; );
2345 while(major_progress() && (loop_opts_cnt > 0)) {
2346 TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2347 assert( cnt++ < 40, "infinite cycle in loop optimization" );
2348 PhaseIdealLoop ideal_loop( igvn, true);
2349 loop_opts_cnt--;
2350 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
2351 if (failing()) return;
2352 }
2353 }
2354 // Ensure that major progress is now clear
2355 C->clear_major_progress();
2356
2357 {
2358 // Verify that all previous optimizations produced a valid graph
2359 // at least to this point, even if no loop optimizations were done.
2360 TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2361 PhaseIdealLoop::verify(igvn);
2362 }
2363
2364 if (range_check_cast_count() > 0) {
2365 // No more loop optimizations. Remove all range check dependent CastIINodes.
2366 C->remove_range_check_casts(igvn);
2367 igvn.optimize();
2368 }
2369
2370 {
2371 TracePhase tp("macroExpand", &timers[_t_macroExpand]);
2372 PhaseMacroExpand mex(igvn);
2373 if (mex.expand_macro_nodes()) {
2374 assert(failing(), "must bail out w/ explicit message");
2375 return;
2376 }
2377 }
2378
2379 DEBUG_ONLY( _modified_nodes = NULL; )
2380 } // (End scope of igvn; run destructor if necessary for asserts.)
2381
2382 process_print_inlining();
2383 // A method with only infinite loops has no edges entering loops from root
2384 {
2385 TracePhase tp("graphReshape", &timers[_t_graphReshaping]);
2386 if (final_graph_reshaping()) {
2387 assert(failing(), "must bail out w/ explicit message");
2388 return;
2389 }
2390 }
2391
2392 print_method(PHASE_OPTIMIZE_FINISHED, 2);
2393 }
2394
2395 //------------------------------Code_Gen---------------------------------------
2396 // Given a graph, generate code for it
2397 void Compile::Code_Gen() {
2398 if (failing()) {
2399 return;
2400 }
2401
2402 // Perform instruction selection. You might think we could reclaim Matcher
2403 // memory PDQ, but actually the Matcher is used in generating spill code.
2404 // Internals of the Matcher (including some VectorSets) must remain live
2405 // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
2406 // set a bit in reclaimed memory.
2407
2408 // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2409 // nodes. Mapping is only valid at the root of each matched subtree.
2410 NOT_PRODUCT( verify_graph_edges(); )
2411
2412 Matcher matcher;
2413 _matcher = &matcher;
2414 {
2415 TracePhase tp("matcher", &timers[_t_matcher]);
2416 matcher.match();
2417 }
2418 // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2419 // nodes. Mapping is only valid at the root of each matched subtree.
2420 NOT_PRODUCT( verify_graph_edges(); )
2421
2422 // If you have too many nodes, or if matching has failed, bail out
2423 check_node_count(0, "out of nodes matching instructions");
2424 if (failing()) {
2425 return;
2426 }
2427
2428 // Build a proper-looking CFG
2429 PhaseCFG cfg(node_arena(), root(), matcher);
2430 _cfg = &cfg;
2431 {
2432 TracePhase tp("scheduler", &timers[_t_scheduler]);
2433 bool success = cfg.do_global_code_motion();
2434 if (!success) {
2435 return;
2436 }
2437
2438 print_method(PHASE_GLOBAL_CODE_MOTION, 2);
2439 NOT_PRODUCT( verify_graph_edges(); )
2440 debug_only( cfg.verify(); )
2441 }
2442
2443 PhaseChaitin regalloc(unique(), cfg, matcher, false);
2444 _regalloc = ®alloc;
2445 {
2446 TracePhase tp("regalloc", &timers[_t_registerAllocation]);
2447 // Perform register allocation. After Chaitin, use-def chains are
2448 // no longer accurate (at spill code) and so must be ignored.
2449 // Node->LRG->reg mappings are still accurate.
2450 _regalloc->Register_Allocate();
2451
2452 // Bail out if the allocator builds too many nodes
2453 if (failing()) {
2454 return;
2455 }
2456 }
2457
2458 // Prior to register allocation we kept empty basic blocks in case the
2459 // the allocator needed a place to spill. After register allocation we
2460 // are not adding any new instructions. If any basic block is empty, we
2461 // can now safely remove it.
2462 {
2463 TracePhase tp("blockOrdering", &timers[_t_blockOrdering]);
2464 cfg.remove_empty_blocks();
2465 if (do_freq_based_layout()) {
2466 PhaseBlockLayout layout(cfg);
2467 } else {
2468 cfg.set_loop_alignment();
2469 }
2470 cfg.fixup_flow();
2471 }
2472
2473 // Apply peephole optimizations
2474 if( OptoPeephole ) {
2475 TracePhase tp("peephole", &timers[_t_peephole]);
2476 PhasePeephole peep( _regalloc, cfg);
2477 peep.do_transform();
2478 }
2479
2480 // Do late expand if CPU requires this.
2481 if (Matcher::require_postalloc_expand) {
2482 TracePhase tp("postalloc_expand", &timers[_t_postalloc_expand]);
2483 cfg.postalloc_expand(_regalloc);
2484 }
2485
2486 // Convert Nodes to instruction bits in a buffer
2487 {
2488 TraceTime tp("output", &timers[_t_output], CITime);
2489 Output();
2490 }
2491
2492 print_method(PHASE_FINAL_CODE);
2493
2494 // He's dead, Jim.
2495 _cfg = (PhaseCFG*)0xdeadbeef;
2496 _regalloc = (PhaseChaitin*)0xdeadbeef;
2497 }
2498
2499
2500 //------------------------------dump_asm---------------------------------------
2501 // Dump formatted assembly
2502 #ifndef PRODUCT
2503 void Compile::dump_asm(int *pcs, uint pc_limit) {
2504 bool cut_short = false;
2505 tty->print_cr("#");
2506 tty->print("# "); _tf->dump(); tty->cr();
2507 tty->print_cr("#");
2508
2509 // For all blocks
2510 int pc = 0x0; // Program counter
2511 char starts_bundle = ' ';
2512 _regalloc->dump_frame();
2513
2514 Node *n = NULL;
2515 for (uint i = 0; i < _cfg->number_of_blocks(); i++) {
2516 if (VMThread::should_terminate()) {
2517 cut_short = true;
2518 break;
2519 }
2520 Block* block = _cfg->get_block(i);
2521 if (block->is_connector() && !Verbose) {
2522 continue;
2523 }
2524 n = block->head();
2525 if (pcs && n->_idx < pc_limit) {
2526 tty->print("%3.3x ", pcs[n->_idx]);
2527 } else {
2528 tty->print(" ");
2529 }
2530 block->dump_head(_cfg);
2531 if (block->is_connector()) {
2532 tty->print_cr(" # Empty connector block");
2533 } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
2534 tty->print_cr(" # Block is sole successor of call");
2535 }
2536
2537 // For all instructions
2538 Node *delay = NULL;
2539 for (uint j = 0; j < block->number_of_nodes(); j++) {
2540 if (VMThread::should_terminate()) {
2541 cut_short = true;
2542 break;
2543 }
2544 n = block->get_node(j);
2545 if (valid_bundle_info(n)) {
2546 Bundle* bundle = node_bundling(n);
2547 if (bundle->used_in_unconditional_delay()) {
2548 delay = n;
2549 continue;
2550 }
2551 if (bundle->starts_bundle()) {
2552 starts_bundle = '+';
2553 }
2554 }
2555
2556 if (WizardMode) {
2557 n->dump();
2558 }
2559
2560 if( !n->is_Region() && // Dont print in the Assembly
2561 !n->is_Phi() && // a few noisely useless nodes
2562 !n->is_Proj() &&
2563 !n->is_MachTemp() &&
2564 !n->is_SafePointScalarObject() &&
2565 !n->is_Catch() && // Would be nice to print exception table targets
2566 !n->is_MergeMem() && // Not very interesting
2567 !n->is_top() && // Debug info table constants
2568 !(n->is_Con() && !n->is_Mach())// Debug info table constants
2569 ) {
2570 if (pcs && n->_idx < pc_limit)
2571 tty->print("%3.3x", pcs[n->_idx]);
2572 else
2573 tty->print(" ");
2574 tty->print(" %c ", starts_bundle);
2575 starts_bundle = ' ';
2576 tty->print("\t");
2577 n->format(_regalloc, tty);
2578 tty->cr();
2579 }
2580
2581 // If we have an instruction with a delay slot, and have seen a delay,
2582 // then back up and print it
2583 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
2584 assert(delay != NULL, "no unconditional delay instruction");
2585 if (WizardMode) delay->dump();
2586
2587 if (node_bundling(delay)->starts_bundle())
2588 starts_bundle = '+';
2589 if (pcs && n->_idx < pc_limit)
2590 tty->print("%3.3x", pcs[n->_idx]);
2591 else
2592 tty->print(" ");
2593 tty->print(" %c ", starts_bundle);
2594 starts_bundle = ' ';
2595 tty->print("\t");
2596 delay->format(_regalloc, tty);
2597 tty->cr();
2598 delay = NULL;
2599 }
2600
2601 // Dump the exception table as well
2602 if( n->is_Catch() && (Verbose || WizardMode) ) {
2603 // Print the exception table for this offset
2604 _handler_table.print_subtable_for(pc);
2605 }
2606 }
2607
2608 if (pcs && n->_idx < pc_limit)
2609 tty->print_cr("%3.3x", pcs[n->_idx]);
2610 else
2611 tty->cr();
2612
2613 assert(cut_short || delay == NULL, "no unconditional delay branch");
2614
2615 } // End of per-block dump
2616 tty->cr();
2617
2618 if (cut_short) tty->print_cr("*** disassembly is cut short ***");
2619 }
2620 #endif
2621
2622 //------------------------------Final_Reshape_Counts---------------------------
2623 // This class defines counters to help identify when a method
2624 // may/must be executed using hardware with only 24-bit precision.
2625 struct Final_Reshape_Counts : public StackObj {
2626 int _call_count; // count non-inlined 'common' calls
2627 int _float_count; // count float ops requiring 24-bit precision
2628 int _double_count; // count double ops requiring more precision
2629 int _java_call_count; // count non-inlined 'java' calls
2630 int _inner_loop_count; // count loops which need alignment
2631 VectorSet _visited; // Visitation flags
2632 Node_List _tests; // Set of IfNodes & PCTableNodes
2633
2634 Final_Reshape_Counts() :
2635 _call_count(0), _float_count(0), _double_count(0),
2636 _java_call_count(0), _inner_loop_count(0),
2637 _visited( Thread::current()->resource_area() ) { }
2638
2639 void inc_call_count () { _call_count ++; }
2640 void inc_float_count () { _float_count ++; }
2641 void inc_double_count() { _double_count++; }
2642 void inc_java_call_count() { _java_call_count++; }
2643 void inc_inner_loop_count() { _inner_loop_count++; }
2644
2645 int get_call_count () const { return _call_count ; }
2646 int get_float_count () const { return _float_count ; }
2647 int get_double_count() const { return _double_count; }
2648 int get_java_call_count() const { return _java_call_count; }
2649 int get_inner_loop_count() const { return _inner_loop_count; }
2650 };
2651
2652 #ifdef ASSERT
2653 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
2654 ciInstanceKlass *k = tp->klass()->as_instance_klass();
2655 // Make sure the offset goes inside the instance layout.
2656 return k->contains_field_offset(tp->offset());
2657 // Note that OffsetBot and OffsetTop are very negative.
2658 }
2659 #endif
2660
2661 // Eliminate trivially redundant StoreCMs and accumulate their
2662 // precedence edges.
2663 void Compile::eliminate_redundant_card_marks(Node* n) {
2664 assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
2665 if (n->in(MemNode::Address)->outcnt() > 1) {
2666 // There are multiple users of the same address so it might be
2667 // possible to eliminate some of the StoreCMs
2668 Node* mem = n->in(MemNode::Memory);
2669 Node* adr = n->in(MemNode::Address);
2670 Node* val = n->in(MemNode::ValueIn);
2671 Node* prev = n;
2672 bool done = false;
2673 // Walk the chain of StoreCMs eliminating ones that match. As
2674 // long as it's a chain of single users then the optimization is
2675 // safe. Eliminating partially redundant StoreCMs would require
2676 // cloning copies down the other paths.
2677 while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
2678 if (adr == mem->in(MemNode::Address) &&
2679 val == mem->in(MemNode::ValueIn)) {
2680 // redundant StoreCM
2681 if (mem->req() > MemNode::OopStore) {
2682 // Hasn't been processed by this code yet.
2683 n->add_prec(mem->in(MemNode::OopStore));
2684 } else {
2685 // Already converted to precedence edge
2686 for (uint i = mem->req(); i < mem->len(); i++) {
2687 // Accumulate any precedence edges
2688 if (mem->in(i) != NULL) {
2689 n->add_prec(mem->in(i));
2690 }
2691 }
2692 // Everything above this point has been processed.
2693 done = true;
2694 }
2695 // Eliminate the previous StoreCM
2696 prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
2697 assert(mem->outcnt() == 0, "should be dead");
2698 mem->disconnect_inputs(NULL, this);
2699 } else {
2700 prev = mem;
2701 }
2702 mem = prev->in(MemNode::Memory);
2703 }
2704 }
2705 }
2706
2707
2708 //------------------------------final_graph_reshaping_impl----------------------
2709 // Implement items 1-5 from final_graph_reshaping below.
2710 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
2711
2712 if ( n->outcnt() == 0 ) return; // dead node
2713 uint nop = n->Opcode();
2714
2715 // Check for 2-input instruction with "last use" on right input.
2716 // Swap to left input. Implements item (2).
2717 if( n->req() == 3 && // two-input instruction
2718 n->in(1)->outcnt() > 1 && // left use is NOT a last use
2719 (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
2720 n->in(2)->outcnt() == 1 &&// right use IS a last use
2721 !n->in(2)->is_Con() ) { // right use is not a constant
2722 // Check for commutative opcode
2723 switch( nop ) {
2724 case Op_AddI: case Op_AddF: case Op_AddD: case Op_AddL:
2725 case Op_MaxI: case Op_MinI:
2726 case Op_MulI: case Op_MulF: case Op_MulD: case Op_MulL:
2727 case Op_AndL: case Op_XorL: case Op_OrL:
2728 case Op_AndI: case Op_XorI: case Op_OrI: {
2729 // Move "last use" input to left by swapping inputs
2730 n->swap_edges(1, 2);
2731 break;
2732 }
2733 default:
2734 break;
2735 }
2736 }
2737
2738 #ifdef ASSERT
2739 if( n->is_Mem() ) {
2740 int alias_idx = get_alias_index(n->as_Mem()->adr_type());
2741 assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
2742 // oop will be recorded in oop map if load crosses safepoint
2743 n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
2744 LoadNode::is_immutable_value(n->in(MemNode::Address))),
2745 "raw memory operations should have control edge");
2746 }
2747 #endif
2748 // Count FPU ops and common calls, implements item (3)
2749 switch( nop ) {
2750 // Count all float operations that may use FPU
2751 case Op_AddF:
2752 case Op_SubF:
2753 case Op_MulF:
2754 case Op_DivF:
2755 case Op_NegF:
2756 case Op_ModF:
2757 case Op_ConvI2F:
2758 case Op_ConF:
2759 case Op_CmpF:
2760 case Op_CmpF3:
2761 // case Op_ConvL2F: // longs are split into 32-bit halves
2762 frc.inc_float_count();
2763 break;
2764
2765 case Op_ConvF2D:
2766 case Op_ConvD2F:
2767 frc.inc_float_count();
2768 frc.inc_double_count();
2769 break;
2770
2771 // Count all double operations that may use FPU
2772 case Op_AddD:
2773 case Op_SubD:
2774 case Op_MulD:
2775 case Op_DivD:
2776 case Op_NegD:
2777 case Op_ModD:
2778 case Op_ConvI2D:
2779 case Op_ConvD2I:
2780 // case Op_ConvL2D: // handled by leaf call
2781 // case Op_ConvD2L: // handled by leaf call
2782 case Op_ConD:
2783 case Op_CmpD:
2784 case Op_CmpD3:
2785 frc.inc_double_count();
2786 break;
2787 case Op_Opaque1: // Remove Opaque Nodes before matching
2788 case Op_Opaque2: // Remove Opaque Nodes before matching
2789 case Op_Opaque3:
2790 n->subsume_by(n->in(1), this);
2791 break;
2792 case Op_CallStaticJava:
2793 case Op_CallJava:
2794 case Op_CallDynamicJava:
2795 frc.inc_java_call_count(); // Count java call site;
2796 case Op_CallRuntime:
2797 case Op_CallLeaf:
2798 case Op_CallLeafNoFP: {
2799 assert( n->is_Call(), "" );
2800 CallNode *call = n->as_Call();
2801 // Count call sites where the FP mode bit would have to be flipped.
2802 // Do not count uncommon runtime calls:
2803 // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
2804 // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
2805 if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
2806 frc.inc_call_count(); // Count the call site
2807 } else { // See if uncommon argument is shared
2808 Node *n = call->in(TypeFunc::Parms);
2809 int nop = n->Opcode();
2810 // Clone shared simple arguments to uncommon calls, item (1).
2811 if( n->outcnt() > 1 &&
2812 !n->is_Proj() &&
2813 nop != Op_CreateEx &&
2814 nop != Op_CheckCastPP &&
2815 nop != Op_DecodeN &&
2816 nop != Op_DecodeNKlass &&
2817 !n->is_Mem() ) {
2818 Node *x = n->clone();
2819 call->set_req( TypeFunc::Parms, x );
2820 }
2821 }
2822 break;
2823 }
2824
2825 case Op_StoreD:
2826 case Op_LoadD:
2827 case Op_LoadD_unaligned:
2828 frc.inc_double_count();
2829 goto handle_mem;
2830 case Op_StoreF:
2831 case Op_LoadF:
2832 frc.inc_float_count();
2833 goto handle_mem;
2834
2835 case Op_StoreCM:
2836 {
2837 // Convert OopStore dependence into precedence edge
2838 Node* prec = n->in(MemNode::OopStore);
2839 n->del_req(MemNode::OopStore);
2840 n->add_prec(prec);
2841 eliminate_redundant_card_marks(n);
2842 }
2843
2844 // fall through
2845
2846 case Op_StoreB:
2847 case Op_StoreC:
2848 case Op_StorePConditional:
2849 case Op_StoreI:
2850 case Op_StoreL:
2851 case Op_StoreIConditional:
2852 case Op_StoreLConditional:
2853 case Op_CompareAndSwapB:
2854 case Op_CompareAndSwapS:
2855 case Op_CompareAndSwapI:
2856 case Op_CompareAndSwapL:
2857 case Op_CompareAndSwapP:
2858 case Op_CompareAndSwapN:
2859 case Op_WeakCompareAndSwapB:
2860 case Op_WeakCompareAndSwapS:
2861 case Op_WeakCompareAndSwapI:
2862 case Op_WeakCompareAndSwapL:
2863 case Op_WeakCompareAndSwapP:
2864 case Op_WeakCompareAndSwapN:
2865 case Op_CompareAndExchangeB:
2866 case Op_CompareAndExchangeS:
2867 case Op_CompareAndExchangeI:
2868 case Op_CompareAndExchangeL:
2869 case Op_CompareAndExchangeP:
2870 case Op_CompareAndExchangeN:
2871 case Op_GetAndAddS:
2872 case Op_GetAndAddB:
2873 case Op_GetAndAddI:
2874 case Op_GetAndAddL:
2875 case Op_GetAndSetS:
2876 case Op_GetAndSetB:
2877 case Op_GetAndSetI:
2878 case Op_GetAndSetL:
2879 case Op_GetAndSetP:
2880 case Op_GetAndSetN:
2881 case Op_StoreP:
2882 case Op_StoreN:
2883 case Op_StoreNKlass:
2884 case Op_LoadB:
2885 case Op_LoadUB:
2886 case Op_LoadUS:
2887 case Op_LoadI:
2888 case Op_LoadKlass:
2889 case Op_LoadNKlass:
2890 case Op_LoadL:
2891 case Op_LoadL_unaligned:
2892 case Op_LoadPLocked:
2893 case Op_LoadP:
2894 case Op_LoadN:
2895 case Op_LoadRange:
2896 case Op_LoadS: {
2897 handle_mem:
2898 #ifdef ASSERT
2899 if( VerifyOptoOopOffsets ) {
2900 assert( n->is_Mem(), "" );
2901 MemNode *mem = (MemNode*)n;
2902 // Check to see if address types have grounded out somehow.
2903 const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
2904 assert( !tp || oop_offset_is_sane(tp), "" );
2905 }
2906 #endif
2907 break;
2908 }
2909
2910 case Op_AddP: { // Assert sane base pointers
2911 Node *addp = n->in(AddPNode::Address);
2912 assert( !addp->is_AddP() ||
2913 addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
2914 addp->in(AddPNode::Base) == n->in(AddPNode::Base),
2915 "Base pointers must match (addp %u)", addp->_idx );
2916 #ifdef _LP64
2917 if ((UseCompressedOops || UseCompressedClassPointers) &&
2918 addp->Opcode() == Op_ConP &&
2919 addp == n->in(AddPNode::Base) &&
2920 n->in(AddPNode::Offset)->is_Con()) {
2921 // If the transformation of ConP to ConN+DecodeN is beneficial depends
2922 // on the platform and on the compressed oops mode.
2923 // Use addressing with narrow klass to load with offset on x86.
2924 // Some platforms can use the constant pool to load ConP.
2925 // Do this transformation here since IGVN will convert ConN back to ConP.
2926 const Type* t = addp->bottom_type();
2927 bool is_oop = t->isa_oopptr() != NULL;
2928 bool is_klass = t->isa_klassptr() != NULL;
2929
2930 if ((is_oop && Matcher::const_oop_prefer_decode() ) ||
2931 (is_klass && Matcher::const_klass_prefer_decode())) {
2932 Node* nn = NULL;
2933
2934 int op = is_oop ? Op_ConN : Op_ConNKlass;
2935
2936 // Look for existing ConN node of the same exact type.
2937 Node* r = root();
2938 uint cnt = r->outcnt();
2939 for (uint i = 0; i < cnt; i++) {
2940 Node* m = r->raw_out(i);
2941 if (m!= NULL && m->Opcode() == op &&
2942 m->bottom_type()->make_ptr() == t) {
2943 nn = m;
2944 break;
2945 }
2946 }
2947 if (nn != NULL) {
2948 // Decode a narrow oop to match address
2949 // [R12 + narrow_oop_reg<<3 + offset]
2950 if (is_oop) {
2951 nn = new DecodeNNode(nn, t);
2952 } else {
2953 nn = new DecodeNKlassNode(nn, t);
2954 }
2955 // Check for succeeding AddP which uses the same Base.
2956 // Otherwise we will run into the assertion above when visiting that guy.
2957 for (uint i = 0; i < n->outcnt(); ++i) {
2958 Node *out_i = n->raw_out(i);
2959 if (out_i && out_i->is_AddP() && out_i->in(AddPNode::Base) == addp) {
2960 out_i->set_req(AddPNode::Base, nn);
2961 #ifdef ASSERT
2962 for (uint j = 0; j < out_i->outcnt(); ++j) {
2963 Node *out_j = out_i->raw_out(j);
2964 assert(out_j == NULL || !out_j->is_AddP() || out_j->in(AddPNode::Base) != addp,
2965 "more than 2 AddP nodes in a chain (out_j %u)", out_j->_idx);
2966 }
2967 #endif
2968 }
2969 }
2970 n->set_req(AddPNode::Base, nn);
2971 n->set_req(AddPNode::Address, nn);
2972 if (addp->outcnt() == 0) {
2973 addp->disconnect_inputs(NULL, this);
2974 }
2975 }
2976 }
2977 }
2978 #endif
2979 // platform dependent reshaping of the address expression
2980 reshape_address(n->as_AddP());
2981 break;
2982 }
2983
2984 case Op_CastPP: {
2985 // Remove CastPP nodes to gain more freedom during scheduling but
2986 // keep the dependency they encode as control or precedence edges
2987 // (if control is set already) on memory operations. Some CastPP
2988 // nodes don't have a control (don't carry a dependency): skip
2989 // those.
2990 if (n->in(0) != NULL) {
2991 ResourceMark rm;
2992 Unique_Node_List wq;
2993 wq.push(n);
2994 for (uint next = 0; next < wq.size(); ++next) {
2995 Node *m = wq.at(next);
2996 for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
2997 Node* use = m->fast_out(i);
2998 if (use->is_Mem() || use->is_EncodeNarrowPtr()) {
2999 use->ensure_control_or_add_prec(n->in(0));
3000 } else {
3001 switch(use->Opcode()) {
3002 case Op_AddP:
3003 case Op_DecodeN:
3004 case Op_DecodeNKlass:
3005 case Op_CheckCastPP:
3006 case Op_CastPP:
3007 wq.push(use);
3008 break;
3009 }
3010 }
3011 }
3012 }
3013 }
3014 const bool is_LP64 = LP64_ONLY(true) NOT_LP64(false);
3015 if (is_LP64 && n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
3016 Node* in1 = n->in(1);
3017 const Type* t = n->bottom_type();
3018 Node* new_in1 = in1->clone();
3019 new_in1->as_DecodeN()->set_type(t);
3020
3021 if (!Matcher::narrow_oop_use_complex_address()) {
3022 //
3023 // x86, ARM and friends can handle 2 adds in addressing mode
3024 // and Matcher can fold a DecodeN node into address by using
3025 // a narrow oop directly and do implicit NULL check in address:
3026 //
3027 // [R12 + narrow_oop_reg<<3 + offset]
3028 // NullCheck narrow_oop_reg
3029 //
3030 // On other platforms (Sparc) we have to keep new DecodeN node and
3031 // use it to do implicit NULL check in address:
3032 //
3033 // decode_not_null narrow_oop_reg, base_reg
3034 // [base_reg + offset]
3035 // NullCheck base_reg
3036 //
3037 // Pin the new DecodeN node to non-null path on these platform (Sparc)
3038 // to keep the information to which NULL check the new DecodeN node
3039 // corresponds to use it as value in implicit_null_check().
3040 //
3041 new_in1->set_req(0, n->in(0));
3042 }
3043
3044 n->subsume_by(new_in1, this);
3045 if (in1->outcnt() == 0) {
3046 in1->disconnect_inputs(NULL, this);
3047 }
3048 } else {
3049 n->subsume_by(n->in(1), this);
3050 if (n->outcnt() == 0) {
3051 n->disconnect_inputs(NULL, this);
3052 }
3053 }
3054 break;
3055 }
3056 #ifdef _LP64
3057 case Op_CmpP:
3058 // Do this transformation here to preserve CmpPNode::sub() and
3059 // other TypePtr related Ideal optimizations (for example, ptr nullness).
3060 if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
3061 Node* in1 = n->in(1);
3062 Node* in2 = n->in(2);
3063 if (!in1->is_DecodeNarrowPtr()) {
3064 in2 = in1;
3065 in1 = n->in(2);
3066 }
3067 assert(in1->is_DecodeNarrowPtr(), "sanity");
3068
3069 Node* new_in2 = NULL;
3070 if (in2->is_DecodeNarrowPtr()) {
3071 assert(in2->Opcode() == in1->Opcode(), "must be same node type");
3072 new_in2 = in2->in(1);
3073 } else if (in2->Opcode() == Op_ConP) {
3074 const Type* t = in2->bottom_type();
3075 if (t == TypePtr::NULL_PTR) {
3076 assert(in1->is_DecodeN(), "compare klass to null?");
3077 // Don't convert CmpP null check into CmpN if compressed
3078 // oops implicit null check is not generated.
3079 // This will allow to generate normal oop implicit null check.
3080 if (Matcher::gen_narrow_oop_implicit_null_checks())
3081 new_in2 = ConNode::make(TypeNarrowOop::NULL_PTR);
3082 //
3083 // This transformation together with CastPP transformation above
3084 // will generated code for implicit NULL checks for compressed oops.
3085 //
3086 // The original code after Optimize()
3087 //
3088 // LoadN memory, narrow_oop_reg
3089 // decode narrow_oop_reg, base_reg
3090 // CmpP base_reg, NULL
3091 // CastPP base_reg // NotNull
3092 // Load [base_reg + offset], val_reg
3093 //
3094 // after these transformations will be
3095 //
3096 // LoadN memory, narrow_oop_reg
3097 // CmpN narrow_oop_reg, NULL
3098 // decode_not_null narrow_oop_reg, base_reg
3099 // Load [base_reg + offset], val_reg
3100 //
3101 // and the uncommon path (== NULL) will use narrow_oop_reg directly
3102 // since narrow oops can be used in debug info now (see the code in
3103 // final_graph_reshaping_walk()).
3104 //
3105 // At the end the code will be matched to
3106 // on x86:
3107 //
3108 // Load_narrow_oop memory, narrow_oop_reg
3109 // Load [R12 + narrow_oop_reg<<3 + offset], val_reg
3110 // NullCheck narrow_oop_reg
3111 //
3112 // and on sparc:
3113 //
3114 // Load_narrow_oop memory, narrow_oop_reg
3115 // decode_not_null narrow_oop_reg, base_reg
3116 // Load [base_reg + offset], val_reg
3117 // NullCheck base_reg
3118 //
3119 } else if (t->isa_oopptr()) {
3120 new_in2 = ConNode::make(t->make_narrowoop());
3121 } else if (t->isa_klassptr()) {
3122 new_in2 = ConNode::make(t->make_narrowklass());
3123 }
3124 }
3125 if (new_in2 != NULL) {
3126 Node* cmpN = new CmpNNode(in1->in(1), new_in2);
3127 n->subsume_by(cmpN, this);
3128 if (in1->outcnt() == 0) {
3129 in1->disconnect_inputs(NULL, this);
3130 }
3131 if (in2->outcnt() == 0) {
3132 in2->disconnect_inputs(NULL, this);
3133 }
3134 }
3135 }
3136 break;
3137
3138 case Op_DecodeN:
3139 case Op_DecodeNKlass:
3140 assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
3141 // DecodeN could be pinned when it can't be fold into
3142 // an address expression, see the code for Op_CastPP above.
3143 assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
3144 break;
3145
3146 case Op_EncodeP:
3147 case Op_EncodePKlass: {
3148 Node* in1 = n->in(1);
3149 if (in1->is_DecodeNarrowPtr()) {
3150 n->subsume_by(in1->in(1), this);
3151 } else if (in1->Opcode() == Op_ConP) {
3152 const Type* t = in1->bottom_type();
3153 if (t == TypePtr::NULL_PTR) {
3154 assert(t->isa_oopptr(), "null klass?");
3155 n->subsume_by(ConNode::make(TypeNarrowOop::NULL_PTR), this);
3156 } else if (t->isa_oopptr()) {
3157 n->subsume_by(ConNode::make(t->make_narrowoop()), this);
3158 } else if (t->isa_klassptr()) {
3159 n->subsume_by(ConNode::make(t->make_narrowklass()), this);
3160 }
3161 }
3162 if (in1->outcnt() == 0) {
3163 in1->disconnect_inputs(NULL, this);
3164 }
3165 break;
3166 }
3167
3168 case Op_Proj: {
3169 if (OptimizeStringConcat) {
3170 ProjNode* p = n->as_Proj();
3171 if (p->_is_io_use) {
3172 // Separate projections were used for the exception path which
3173 // are normally removed by a late inline. If it wasn't inlined
3174 // then they will hang around and should just be replaced with
3175 // the original one.
3176 Node* proj = NULL;
3177 // Replace with just one
3178 for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
3179 Node *use = i.get();
3180 if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
3181 proj = use;
3182 break;
3183 }
3184 }
3185 assert(proj != NULL, "must be found");
3186 p->subsume_by(proj, this);
3187 }
3188 }
3189 break;
3190 }
3191
3192 case Op_Phi:
3193 if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
3194 // The EncodeP optimization may create Phi with the same edges
3195 // for all paths. It is not handled well by Register Allocator.
3196 Node* unique_in = n->in(1);
3197 assert(unique_in != NULL, "");
3198 uint cnt = n->req();
3199 for (uint i = 2; i < cnt; i++) {
3200 Node* m = n->in(i);
3201 assert(m != NULL, "");
3202 if (unique_in != m)
3203 unique_in = NULL;
3204 }
3205 if (unique_in != NULL) {
3206 n->subsume_by(unique_in, this);
3207 }
3208 }
3209 break;
3210
3211 #endif
3212
3213 #ifdef ASSERT
3214 case Op_CastII:
3215 // Verify that all range check dependent CastII nodes were removed.
3216 if (n->isa_CastII()->has_range_check()) {
3217 n->dump(3);
3218 assert(false, "Range check dependent CastII node was not removed");
3219 }
3220 break;
3221 #endif
3222
3223 case Op_ModI:
3224 if (UseDivMod) {
3225 // Check if a%b and a/b both exist
3226 Node* d = n->find_similar(Op_DivI);
3227 if (d) {
3228 // Replace them with a fused divmod if supported
3229 if (Matcher::has_match_rule(Op_DivModI)) {
3230 DivModINode* divmod = DivModINode::make(n);
3231 d->subsume_by(divmod->div_proj(), this);
3232 n->subsume_by(divmod->mod_proj(), this);
3233 } else {
3234 // replace a%b with a-((a/b)*b)
3235 Node* mult = new MulINode(d, d->in(2));
3236 Node* sub = new SubINode(d->in(1), mult);
3237 n->subsume_by(sub, this);
3238 }
3239 }
3240 }
3241 break;
3242
3243 case Op_ModL:
3244 if (UseDivMod) {
3245 // Check if a%b and a/b both exist
3246 Node* d = n->find_similar(Op_DivL);
3247 if (d) {
3248 // Replace them with a fused divmod if supported
3249 if (Matcher::has_match_rule(Op_DivModL)) {
3250 DivModLNode* divmod = DivModLNode::make(n);
3251 d->subsume_by(divmod->div_proj(), this);
3252 n->subsume_by(divmod->mod_proj(), this);
3253 } else {
3254 // replace a%b with a-((a/b)*b)
3255 Node* mult = new MulLNode(d, d->in(2));
3256 Node* sub = new SubLNode(d->in(1), mult);
3257 n->subsume_by(sub, this);
3258 }
3259 }
3260 }
3261 break;
3262
3263 case Op_LoadVector:
3264 case Op_StoreVector:
3265 break;
3266
3267 case Op_AddReductionVI:
3268 case Op_AddReductionVL:
3269 case Op_AddReductionVF:
3270 case Op_AddReductionVD:
3271 case Op_MulReductionVI:
3272 case Op_MulReductionVL:
3273 case Op_MulReductionVF:
3274 case Op_MulReductionVD:
3275 break;
3276
3277 case Op_PackB:
3278 case Op_PackS:
3279 case Op_PackI:
3280 case Op_PackF:
3281 case Op_PackL:
3282 case Op_PackD:
3283 if (n->req()-1 > 2) {
3284 // Replace many operand PackNodes with a binary tree for matching
3285 PackNode* p = (PackNode*) n;
3286 Node* btp = p->binary_tree_pack(1, n->req());
3287 n->subsume_by(btp, this);
3288 }
3289 break;
3290 case Op_Loop:
3291 case Op_CountedLoop:
3292 if (n->as_Loop()->is_inner_loop()) {
3293 frc.inc_inner_loop_count();
3294 }
3295 break;
3296 case Op_LShiftI:
3297 case Op_RShiftI:
3298 case Op_URShiftI:
3299 case Op_LShiftL:
3300 case Op_RShiftL:
3301 case Op_URShiftL:
3302 if (Matcher::need_masked_shift_count) {
3303 // The cpu's shift instructions don't restrict the count to the
3304 // lower 5/6 bits. We need to do the masking ourselves.
3305 Node* in2 = n->in(2);
3306 juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
3307 const TypeInt* t = in2->find_int_type();
3308 if (t != NULL && t->is_con()) {
3309 juint shift = t->get_con();
3310 if (shift > mask) { // Unsigned cmp
3311 n->set_req(2, ConNode::make(TypeInt::make(shift & mask)));
3312 }
3313 } else {
3314 if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
3315 Node* shift = new AndINode(in2, ConNode::make(TypeInt::make(mask)));
3316 n->set_req(2, shift);
3317 }
3318 }
3319 if (in2->outcnt() == 0) { // Remove dead node
3320 in2->disconnect_inputs(NULL, this);
3321 }
3322 }
3323 break;
3324 case Op_MemBarStoreStore:
3325 case Op_MemBarRelease:
3326 // Break the link with AllocateNode: it is no longer useful and
3327 // confuses register allocation.
3328 if (n->req() > MemBarNode::Precedent) {
3329 n->set_req(MemBarNode::Precedent, top());
3330 }
3331 break;
3332 case Op_RangeCheck: {
3333 RangeCheckNode* rc = n->as_RangeCheck();
3334 Node* iff = new IfNode(rc->in(0), rc->in(1), rc->_prob, rc->_fcnt);
3335 n->subsume_by(iff, this);
3336 frc._tests.push(iff);
3337 break;
3338 }
3339 case Op_ConvI2L: {
3340 if (!Matcher::convi2l_type_required) {
3341 // Code generation on some platforms doesn't need accurate
3342 // ConvI2L types. Widening the type can help remove redundant
3343 // address computations.
3344 n->as_Type()->set_type(TypeLong::INT);
3345 ResourceMark rm;
3346 Node_List wq;
3347 wq.push(n);
3348 for (uint next = 0; next < wq.size(); next++) {
3349 Node *m = wq.at(next);
3350
3351 for(;;) {
3352 // Loop over all nodes with identical inputs edges as m
3353 Node* k = m->find_similar(m->Opcode());
3354 if (k == NULL) {
3355 break;
3356 }
3357 // Push their uses so we get a chance to remove node made
3358 // redundant
3359 for (DUIterator_Fast imax, i = k->fast_outs(imax); i < imax; i++) {
3360 Node* u = k->fast_out(i);
3361 assert(!wq.contains(u), "shouldn't process one node several times");
3362 if (u->Opcode() == Op_LShiftL ||
3363 u->Opcode() == Op_AddL ||
3364 u->Opcode() == Op_SubL ||
3365 u->Opcode() == Op_AddP) {
3366 wq.push(u);
3367 }
3368 }
3369 // Replace all nodes with identical edges as m with m
3370 k->subsume_by(m, this);
3371 }
3372 }
3373 }
3374 break;
3375 }
3376 #ifdef ASSERT
3377 case Op_ValueTypePtr:
3378 case Op_ValueType: {
3379 n->dump(-1);
3380 assert(false, "value type node was not removed");
3381 break;
3382 }
3383 #endif
3384 default:
3385 assert( !n->is_Call(), "" );
3386 assert( !n->is_Mem(), "" );
3387 assert( nop != Op_ProfileBoolean, "should be eliminated during IGVN");
3388 break;
3389 }
3390
3391 // Collect CFG split points
3392 if (n->is_MultiBranch() && !n->is_RangeCheck()) {
3393 frc._tests.push(n);
3394 }
3395 }
3396
3397 //------------------------------final_graph_reshaping_walk---------------------
3398 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
3399 // requires that the walk visits a node's inputs before visiting the node.
3400 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
3401 ResourceArea *area = Thread::current()->resource_area();
3402 Unique_Node_List sfpt(area);
3403
3404 frc._visited.set(root->_idx); // first, mark node as visited
3405 uint cnt = root->req();
3406 Node *n = root;
3407 uint i = 0;
3408 while (true) {
3409 if (i < cnt) {
3410 // Place all non-visited non-null inputs onto stack
3411 Node* m = n->in(i);
3412 ++i;
3413 if (m != NULL && !frc._visited.test_set(m->_idx)) {
3414 if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL) {
3415 // compute worst case interpreter size in case of a deoptimization
3416 update_interpreter_frame_size(m->as_SafePoint()->jvms()->interpreter_frame_size());
3417
3418 sfpt.push(m);
3419 }
3420 cnt = m->req();
3421 nstack.push(n, i); // put on stack parent and next input's index
3422 n = m;
3423 i = 0;
3424 }
3425 } else {
3426 // Now do post-visit work
3427 final_graph_reshaping_impl( n, frc );
3428 if (nstack.is_empty())
3429 break; // finished
3430 n = nstack.node(); // Get node from stack
3431 cnt = n->req();
3432 i = nstack.index();
3433 nstack.pop(); // Shift to the next node on stack
3434 }
3435 }
3436
3437 // Skip next transformation if compressed oops are not used.
3438 if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
3439 (!UseCompressedOops && !UseCompressedClassPointers))
3440 return;
3441
3442 // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
3443 // It could be done for an uncommon traps or any safepoints/calls
3444 // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
3445 while (sfpt.size() > 0) {
3446 n = sfpt.pop();
3447 JVMState *jvms = n->as_SafePoint()->jvms();
3448 assert(jvms != NULL, "sanity");
3449 int start = jvms->debug_start();
3450 int end = n->req();
3451 bool is_uncommon = (n->is_CallStaticJava() &&
3452 n->as_CallStaticJava()->uncommon_trap_request() != 0);
3453 for (int j = start; j < end; j++) {
3454 Node* in = n->in(j);
3455 if (in->is_DecodeNarrowPtr()) {
3456 bool safe_to_skip = true;
3457 if (!is_uncommon ) {
3458 // Is it safe to skip?
3459 for (uint i = 0; i < in->outcnt(); i++) {
3460 Node* u = in->raw_out(i);
3461 if (!u->is_SafePoint() ||
3462 (u->is_Call() && u->as_Call()->has_non_debug_use(n))) {
3463 safe_to_skip = false;
3464 }
3465 }
3466 }
3467 if (safe_to_skip) {
3468 n->set_req(j, in->in(1));
3469 }
3470 if (in->outcnt() == 0) {
3471 in->disconnect_inputs(NULL, this);
3472 }
3473 }
3474 }
3475 }
3476 }
3477
3478 //------------------------------final_graph_reshaping--------------------------
3479 // Final Graph Reshaping.
3480 //
3481 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
3482 // and not commoned up and forced early. Must come after regular
3483 // optimizations to avoid GVN undoing the cloning. Clone constant
3484 // inputs to Loop Phis; these will be split by the allocator anyways.
3485 // Remove Opaque nodes.
3486 // (2) Move last-uses by commutative operations to the left input to encourage
3487 // Intel update-in-place two-address operations and better register usage
3488 // on RISCs. Must come after regular optimizations to avoid GVN Ideal
3489 // calls canonicalizing them back.
3490 // (3) Count the number of double-precision FP ops, single-precision FP ops
3491 // and call sites. On Intel, we can get correct rounding either by
3492 // forcing singles to memory (requires extra stores and loads after each
3493 // FP bytecode) or we can set a rounding mode bit (requires setting and
3494 // clearing the mode bit around call sites). The mode bit is only used
3495 // if the relative frequency of single FP ops to calls is low enough.
3496 // This is a key transform for SPEC mpeg_audio.
3497 // (4) Detect infinite loops; blobs of code reachable from above but not
3498 // below. Several of the Code_Gen algorithms fail on such code shapes,
3499 // so we simply bail out. Happens a lot in ZKM.jar, but also happens
3500 // from time to time in other codes (such as -Xcomp finalizer loops, etc).
3501 // Detection is by looking for IfNodes where only 1 projection is
3502 // reachable from below or CatchNodes missing some targets.
3503 // (5) Assert for insane oop offsets in debug mode.
3504
3505 bool Compile::final_graph_reshaping() {
3506 // an infinite loop may have been eliminated by the optimizer,
3507 // in which case the graph will be empty.
3508 if (root()->req() == 1) {
3509 record_method_not_compilable("trivial infinite loop");
3510 return true;
3511 }
3512
3513 // Expensive nodes have their control input set to prevent the GVN
3514 // from freely commoning them. There's no GVN beyond this point so
3515 // no need to keep the control input. We want the expensive nodes to
3516 // be freely moved to the least frequent code path by gcm.
3517 assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
3518 for (int i = 0; i < expensive_count(); i++) {
3519 _expensive_nodes->at(i)->set_req(0, NULL);
3520 }
3521
3522 Final_Reshape_Counts frc;
3523
3524 // Visit everybody reachable!
3525 // Allocate stack of size C->live_nodes()/2 to avoid frequent realloc
3526 Node_Stack nstack(live_nodes() >> 1);
3527 final_graph_reshaping_walk(nstack, root(), frc);
3528
3529 // Check for unreachable (from below) code (i.e., infinite loops).
3530 for( uint i = 0; i < frc._tests.size(); i++ ) {
3531 MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
3532 // Get number of CFG targets.
3533 // Note that PCTables include exception targets after calls.
3534 uint required_outcnt = n->required_outcnt();
3535 if (n->outcnt() != required_outcnt) {
3536 // Check for a few special cases. Rethrow Nodes never take the
3537 // 'fall-thru' path, so expected kids is 1 less.
3538 if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
3539 if (n->in(0)->in(0)->is_Call()) {
3540 CallNode *call = n->in(0)->in(0)->as_Call();
3541 if (call->entry_point() == OptoRuntime::rethrow_stub()) {
3542 required_outcnt--; // Rethrow always has 1 less kid
3543 } else if (call->req() > TypeFunc::Parms &&
3544 call->is_CallDynamicJava()) {
3545 // Check for null receiver. In such case, the optimizer has
3546 // detected that the virtual call will always result in a null
3547 // pointer exception. The fall-through projection of this CatchNode
3548 // will not be populated.
3549 Node *arg0 = call->in(TypeFunc::Parms);
3550 if (arg0->is_Type() &&
3551 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
3552 required_outcnt--;
3553 }
3554 } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
3555 call->req() > TypeFunc::Parms+1 &&
3556 call->is_CallStaticJava()) {
3557 // Check for negative array length. In such case, the optimizer has
3558 // detected that the allocation attempt will always result in an
3559 // exception. There is no fall-through projection of this CatchNode .
3560 Node *arg1 = call->in(TypeFunc::Parms+1);
3561 if (arg1->is_Type() &&
3562 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
3563 required_outcnt--;
3564 }
3565 }
3566 }
3567 }
3568 // Recheck with a better notion of 'required_outcnt'
3569 if (n->outcnt() != required_outcnt) {
3570 assert(false, "malformed control flow");
3571 record_method_not_compilable("malformed control flow");
3572 return true; // Not all targets reachable!
3573 }
3574 }
3575 // Check that I actually visited all kids. Unreached kids
3576 // must be infinite loops.
3577 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
3578 if (!frc._visited.test(n->fast_out(j)->_idx)) {
3579 record_method_not_compilable("infinite loop");
3580 assert(false, "infinite loop");
3581 return true; // Found unvisited kid; must be unreach
3582 }
3583 }
3584
3585 // If original bytecodes contained a mixture of floats and doubles
3586 // check if the optimizer has made it homogenous, item (3).
3587 if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
3588 frc.get_float_count() > 32 &&
3589 frc.get_double_count() == 0 &&
3590 (10 * frc.get_call_count() < frc.get_float_count()) ) {
3591 set_24_bit_selection_and_mode( false, true );
3592 }
3593
3594 set_java_calls(frc.get_java_call_count());
3595 set_inner_loops(frc.get_inner_loop_count());
3596
3597 // No infinite loops, no reason to bail out.
3598 return false;
3599 }
3600
3601 //-----------------------------too_many_traps----------------------------------
3602 // Report if there are too many traps at the current method and bci.
3603 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
3604 bool Compile::too_many_traps(ciMethod* method,
3605 int bci,
3606 Deoptimization::DeoptReason reason) {
3607 ciMethodData* md = method->method_data();
3608 if (md->is_empty()) {
3609 // Assume the trap has not occurred, or that it occurred only
3610 // because of a transient condition during start-up in the interpreter.
3611 return false;
3612 }
3613 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3614 if (md->has_trap_at(bci, m, reason) != 0) {
3615 // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
3616 // Also, if there are multiple reasons, or if there is no per-BCI record,
3617 // assume the worst.
3618 if (log())
3619 log()->elem("observe trap='%s' count='%d'",
3620 Deoptimization::trap_reason_name(reason),
3621 md->trap_count(reason));
3622 return true;
3623 } else {
3624 // Ignore method/bci and see if there have been too many globally.
3625 return too_many_traps(reason, md);
3626 }
3627 }
3628
3629 // Less-accurate variant which does not require a method and bci.
3630 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
3631 ciMethodData* logmd) {
3632 if (trap_count(reason) >= Deoptimization::per_method_trap_limit(reason)) {
3633 // Too many traps globally.
3634 // Note that we use cumulative trap_count, not just md->trap_count.
3635 if (log()) {
3636 int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
3637 log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
3638 Deoptimization::trap_reason_name(reason),
3639 mcount, trap_count(reason));
3640 }
3641 return true;
3642 } else {
3643 // The coast is clear.
3644 return false;
3645 }
3646 }
3647
3648 //--------------------------too_many_recompiles--------------------------------
3649 // Report if there are too many recompiles at the current method and bci.
3650 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
3651 // Is not eager to return true, since this will cause the compiler to use
3652 // Action_none for a trap point, to avoid too many recompilations.
3653 bool Compile::too_many_recompiles(ciMethod* method,
3654 int bci,
3655 Deoptimization::DeoptReason reason) {
3656 ciMethodData* md = method->method_data();
3657 if (md->is_empty()) {
3658 // Assume the trap has not occurred, or that it occurred only
3659 // because of a transient condition during start-up in the interpreter.
3660 return false;
3661 }
3662 // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
3663 uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
3664 uint m_cutoff = (uint) PerMethodRecompilationCutoff / 2 + 1; // not zero
3665 Deoptimization::DeoptReason per_bc_reason
3666 = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
3667 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3668 if ((per_bc_reason == Deoptimization::Reason_none
3669 || md->has_trap_at(bci, m, reason) != 0)
3670 // The trap frequency measure we care about is the recompile count:
3671 && md->trap_recompiled_at(bci, m)
3672 && md->overflow_recompile_count() >= bc_cutoff) {
3673 // Do not emit a trap here if it has already caused recompilations.
3674 // Also, if there are multiple reasons, or if there is no per-BCI record,
3675 // assume the worst.
3676 if (log())
3677 log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
3678 Deoptimization::trap_reason_name(reason),
3679 md->trap_count(reason),
3680 md->overflow_recompile_count());
3681 return true;
3682 } else if (trap_count(reason) != 0
3683 && decompile_count() >= m_cutoff) {
3684 // Too many recompiles globally, and we have seen this sort of trap.
3685 // Use cumulative decompile_count, not just md->decompile_count.
3686 if (log())
3687 log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
3688 Deoptimization::trap_reason_name(reason),
3689 md->trap_count(reason), trap_count(reason),
3690 md->decompile_count(), decompile_count());
3691 return true;
3692 } else {
3693 // The coast is clear.
3694 return false;
3695 }
3696 }
3697
3698 // Compute when not to trap. Used by matching trap based nodes and
3699 // NullCheck optimization.
3700 void Compile::set_allowed_deopt_reasons() {
3701 _allowed_reasons = 0;
3702 if (is_method_compilation()) {
3703 for (int rs = (int)Deoptimization::Reason_none+1; rs < Compile::trapHistLength; rs++) {
3704 assert(rs < BitsPerInt, "recode bit map");
3705 if (!too_many_traps((Deoptimization::DeoptReason) rs)) {
3706 _allowed_reasons |= nth_bit(rs);
3707 }
3708 }
3709 }
3710 }
3711
3712 #ifndef PRODUCT
3713 //------------------------------verify_graph_edges---------------------------
3714 // Walk the Graph and verify that there is a one-to-one correspondence
3715 // between Use-Def edges and Def-Use edges in the graph.
3716 void Compile::verify_graph_edges(bool no_dead_code) {
3717 if (VerifyGraphEdges) {
3718 ResourceArea *area = Thread::current()->resource_area();
3719 Unique_Node_List visited(area);
3720 // Call recursive graph walk to check edges
3721 _root->verify_edges(visited);
3722 if (no_dead_code) {
3723 // Now make sure that no visited node is used by an unvisited node.
3724 bool dead_nodes = false;
3725 Unique_Node_List checked(area);
3726 while (visited.size() > 0) {
3727 Node* n = visited.pop();
3728 checked.push(n);
3729 for (uint i = 0; i < n->outcnt(); i++) {
3730 Node* use = n->raw_out(i);
3731 if (checked.member(use)) continue; // already checked
3732 if (visited.member(use)) continue; // already in the graph
3733 if (use->is_Con()) continue; // a dead ConNode is OK
3734 // At this point, we have found a dead node which is DU-reachable.
3735 if (!dead_nodes) {
3736 tty->print_cr("*** Dead nodes reachable via DU edges:");
3737 dead_nodes = true;
3738 }
3739 use->dump(2);
3740 tty->print_cr("---");
3741 checked.push(use); // No repeats; pretend it is now checked.
3742 }
3743 }
3744 assert(!dead_nodes, "using nodes must be reachable from root");
3745 }
3746 }
3747 }
3748
3749 // Verify GC barriers consistency
3750 // Currently supported:
3751 // - G1 pre-barriers (see GraphKit::g1_write_barrier_pre())
3752 void Compile::verify_barriers() {
3753 if (UseG1GC) {
3754 // Verify G1 pre-barriers
3755 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + SATBMarkQueue::byte_offset_of_active());
3756
3757 ResourceArea *area = Thread::current()->resource_area();
3758 Unique_Node_List visited(area);
3759 Node_List worklist(area);
3760 // We're going to walk control flow backwards starting from the Root
3761 worklist.push(_root);
3762 while (worklist.size() > 0) {
3763 Node* x = worklist.pop();
3764 if (x == NULL || x == top()) continue;
3765 if (visited.member(x)) {
3766 continue;
3767 } else {
3768 visited.push(x);
3769 }
3770
3771 if (x->is_Region()) {
3772 for (uint i = 1; i < x->req(); i++) {
3773 worklist.push(x->in(i));
3774 }
3775 } else {
3776 worklist.push(x->in(0));
3777 // We are looking for the pattern:
3778 // /->ThreadLocal
3779 // If->Bool->CmpI->LoadB->AddP->ConL(marking_offset)
3780 // \->ConI(0)
3781 // We want to verify that the If and the LoadB have the same control
3782 // See GraphKit::g1_write_barrier_pre()
3783 if (x->is_If()) {
3784 IfNode *iff = x->as_If();
3785 if (iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) {
3786 CmpNode *cmp = iff->in(1)->in(1)->as_Cmp();
3787 if (cmp->Opcode() == Op_CmpI && cmp->in(2)->is_Con() && cmp->in(2)->bottom_type()->is_int()->get_con() == 0
3788 && cmp->in(1)->is_Load()) {
3789 LoadNode* load = cmp->in(1)->as_Load();
3790 if (load->Opcode() == Op_LoadB && load->in(2)->is_AddP() && load->in(2)->in(2)->Opcode() == Op_ThreadLocal
3791 && load->in(2)->in(3)->is_Con()
3792 && load->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == marking_offset) {
3793
3794 Node* if_ctrl = iff->in(0);
3795 Node* load_ctrl = load->in(0);
3796
3797 if (if_ctrl != load_ctrl) {
3798 // Skip possible CProj->NeverBranch in infinite loops
3799 if ((if_ctrl->is_Proj() && if_ctrl->Opcode() == Op_CProj)
3800 && (if_ctrl->in(0)->is_MultiBranch() && if_ctrl->in(0)->Opcode() == Op_NeverBranch)) {
3801 if_ctrl = if_ctrl->in(0)->in(0);
3802 }
3803 }
3804 assert(load_ctrl != NULL && if_ctrl == load_ctrl, "controls must match");
3805 }
3806 }
3807 }
3808 }
3809 }
3810 }
3811 }
3812 }
3813
3814 #endif
3815
3816 // The Compile object keeps track of failure reasons separately from the ciEnv.
3817 // This is required because there is not quite a 1-1 relation between the
3818 // ciEnv and its compilation task and the Compile object. Note that one
3819 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
3820 // to backtrack and retry without subsuming loads. Other than this backtracking
3821 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
3822 // by the logic in C2Compiler.
3823 void Compile::record_failure(const char* reason) {
3824 if (log() != NULL) {
3825 log()->elem("failure reason='%s' phase='compile'", reason);
3826 }
3827 if (_failure_reason == NULL) {
3828 // Record the first failure reason.
3829 _failure_reason = reason;
3830 }
3831
3832 if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
3833 C->print_method(PHASE_FAILURE);
3834 }
3835 _root = NULL; // flush the graph, too
3836 }
3837
3838 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator)
3839 : TraceTime(name, accumulator, CITime, CITimeVerbose),
3840 _phase_name(name), _dolog(CITimeVerbose)
3841 {
3842 if (_dolog) {
3843 C = Compile::current();
3844 _log = C->log();
3845 } else {
3846 C = NULL;
3847 _log = NULL;
3848 }
3849 if (_log != NULL) {
3850 _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3851 _log->stamp();
3852 _log->end_head();
3853 }
3854 }
3855
3856 Compile::TracePhase::~TracePhase() {
3857
3858 C = Compile::current();
3859 if (_dolog) {
3860 _log = C->log();
3861 } else {
3862 _log = NULL;
3863 }
3864
3865 #ifdef ASSERT
3866 if (PrintIdealNodeCount) {
3867 tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
3868 _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
3869 }
3870
3871 if (VerifyIdealNodeCount) {
3872 Compile::current()->print_missing_nodes();
3873 }
3874 #endif
3875
3876 if (_log != NULL) {
3877 _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3878 }
3879 }
3880
3881 //=============================================================================
3882 // Two Constant's are equal when the type and the value are equal.
3883 bool Compile::Constant::operator==(const Constant& other) {
3884 if (type() != other.type() ) return false;
3885 if (can_be_reused() != other.can_be_reused()) return false;
3886 // For floating point values we compare the bit pattern.
3887 switch (type()) {
3888 case T_INT:
3889 case T_FLOAT: return (_v._value.i == other._v._value.i);
3890 case T_LONG:
3891 case T_DOUBLE: return (_v._value.j == other._v._value.j);
3892 case T_OBJECT:
3893 case T_ADDRESS: return (_v._value.l == other._v._value.l);
3894 case T_VOID: return (_v._value.l == other._v._value.l); // jump-table entries
3895 case T_METADATA: return (_v._metadata == other._v._metadata);
3896 default: ShouldNotReachHere(); return false;
3897 }
3898 }
3899
3900 static int type_to_size_in_bytes(BasicType t) {
3901 switch (t) {
3902 case T_INT: return sizeof(jint );
3903 case T_LONG: return sizeof(jlong );
3904 case T_FLOAT: return sizeof(jfloat );
3905 case T_DOUBLE: return sizeof(jdouble);
3906 case T_METADATA: return sizeof(Metadata*);
3907 // We use T_VOID as marker for jump-table entries (labels) which
3908 // need an internal word relocation.
3909 case T_VOID:
3910 case T_ADDRESS:
3911 case T_OBJECT: return sizeof(jobject);
3912 default:
3913 ShouldNotReachHere();
3914 return -1;
3915 }
3916 }
3917
3918 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
3919 // sort descending
3920 if (a->freq() > b->freq()) return -1;
3921 if (a->freq() < b->freq()) return 1;
3922 return 0;
3923 }
3924
3925 void Compile::ConstantTable::calculate_offsets_and_size() {
3926 // First, sort the array by frequencies.
3927 _constants.sort(qsort_comparator);
3928
3929 #ifdef ASSERT
3930 // Make sure all jump-table entries were sorted to the end of the
3931 // array (they have a negative frequency).
3932 bool found_void = false;
3933 for (int i = 0; i < _constants.length(); i++) {
3934 Constant con = _constants.at(i);
3935 if (con.type() == T_VOID)
3936 found_void = true; // jump-tables
3937 else
3938 assert(!found_void, "wrong sorting");
3939 }
3940 #endif
3941
3942 int offset = 0;
3943 for (int i = 0; i < _constants.length(); i++) {
3944 Constant* con = _constants.adr_at(i);
3945
3946 // Align offset for type.
3947 int typesize = type_to_size_in_bytes(con->type());
3948 offset = align_up(offset, typesize);
3949 con->set_offset(offset); // set constant's offset
3950
3951 if (con->type() == T_VOID) {
3952 MachConstantNode* n = (MachConstantNode*) con->get_jobject();
3953 offset = offset + typesize * n->outcnt(); // expand jump-table
3954 } else {
3955 offset = offset + typesize;
3956 }
3957 }
3958
3959 // Align size up to the next section start (which is insts; see
3960 // CodeBuffer::align_at_start).
3961 assert(_size == -1, "already set?");
3962 _size = align_up(offset, (int)CodeEntryAlignment);
3963 }
3964
3965 void Compile::ConstantTable::emit(CodeBuffer& cb) {
3966 MacroAssembler _masm(&cb);
3967 for (int i = 0; i < _constants.length(); i++) {
3968 Constant con = _constants.at(i);
3969 address constant_addr = NULL;
3970 switch (con.type()) {
3971 case T_INT: constant_addr = _masm.int_constant( con.get_jint() ); break;
3972 case T_LONG: constant_addr = _masm.long_constant( con.get_jlong() ); break;
3973 case T_FLOAT: constant_addr = _masm.float_constant( con.get_jfloat() ); break;
3974 case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
3975 case T_OBJECT: {
3976 jobject obj = con.get_jobject();
3977 int oop_index = _masm.oop_recorder()->find_index(obj);
3978 constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
3979 break;
3980 }
3981 case T_ADDRESS: {
3982 address addr = (address) con.get_jobject();
3983 constant_addr = _masm.address_constant(addr);
3984 break;
3985 }
3986 // We use T_VOID as marker for jump-table entries (labels) which
3987 // need an internal word relocation.
3988 case T_VOID: {
3989 MachConstantNode* n = (MachConstantNode*) con.get_jobject();
3990 // Fill the jump-table with a dummy word. The real value is
3991 // filled in later in fill_jump_table.
3992 address dummy = (address) n;
3993 constant_addr = _masm.address_constant(dummy);
3994 // Expand jump-table
3995 for (uint i = 1; i < n->outcnt(); i++) {
3996 address temp_addr = _masm.address_constant(dummy + i);
3997 assert(temp_addr, "consts section too small");
3998 }
3999 break;
4000 }
4001 case T_METADATA: {
4002 Metadata* obj = con.get_metadata();
4003 int metadata_index = _masm.oop_recorder()->find_index(obj);
4004 constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
4005 break;
4006 }
4007 default: ShouldNotReachHere();
4008 }
4009 assert(constant_addr, "consts section too small");
4010 assert((constant_addr - _masm.code()->consts()->start()) == con.offset(),
4011 "must be: %d == %d", (int) (constant_addr - _masm.code()->consts()->start()), (int)(con.offset()));
4012 }
4013 }
4014
4015 int Compile::ConstantTable::find_offset(Constant& con) const {
4016 int idx = _constants.find(con);
4017 assert(idx != -1, "constant must be in constant table");
4018 int offset = _constants.at(idx).offset();
4019 assert(offset != -1, "constant table not emitted yet?");
4020 return offset;
4021 }
4022
4023 void Compile::ConstantTable::add(Constant& con) {
4024 if (con.can_be_reused()) {
4025 int idx = _constants.find(con);
4026 if (idx != -1 && _constants.at(idx).can_be_reused()) {
4027 _constants.adr_at(idx)->inc_freq(con.freq()); // increase the frequency by the current value
4028 return;
4029 }
4030 }
4031 (void) _constants.append(con);
4032 }
4033
4034 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
4035 Block* b = Compile::current()->cfg()->get_block_for_node(n);
4036 Constant con(type, value, b->_freq);
4037 add(con);
4038 return con;
4039 }
4040
4041 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
4042 Constant con(metadata);
4043 add(con);
4044 return con;
4045 }
4046
4047 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
4048 jvalue value;
4049 BasicType type = oper->type()->basic_type();
4050 switch (type) {
4051 case T_LONG: value.j = oper->constantL(); break;
4052 case T_FLOAT: value.f = oper->constantF(); break;
4053 case T_DOUBLE: value.d = oper->constantD(); break;
4054 case T_OBJECT:
4055 case T_ADDRESS: value.l = (jobject) oper->constant(); break;
4056 case T_METADATA: return add((Metadata*)oper->constant()); break;
4057 default: guarantee(false, "unhandled type: %s", type2name(type));
4058 }
4059 return add(n, type, value);
4060 }
4061
4062 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
4063 jvalue value;
4064 // We can use the node pointer here to identify the right jump-table
4065 // as this method is called from Compile::Fill_buffer right before
4066 // the MachNodes are emitted and the jump-table is filled (means the
4067 // MachNode pointers do not change anymore).
4068 value.l = (jobject) n;
4069 Constant con(T_VOID, value, next_jump_table_freq(), false); // Labels of a jump-table cannot be reused.
4070 add(con);
4071 return con;
4072 }
4073
4074 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
4075 // If called from Compile::scratch_emit_size do nothing.
4076 if (Compile::current()->in_scratch_emit_size()) return;
4077
4078 assert(labels.is_nonempty(), "must be");
4079 assert((uint) labels.length() == n->outcnt(), "must be equal: %d == %d", labels.length(), n->outcnt());
4080
4081 // Since MachConstantNode::constant_offset() also contains
4082 // table_base_offset() we need to subtract the table_base_offset()
4083 // to get the plain offset into the constant table.
4084 int offset = n->constant_offset() - table_base_offset();
4085
4086 MacroAssembler _masm(&cb);
4087 address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
4088
4089 for (uint i = 0; i < n->outcnt(); i++) {
4090 address* constant_addr = &jump_table_base[i];
4091 assert(*constant_addr == (((address) n) + i), "all jump-table entries must contain adjusted node pointer: " INTPTR_FORMAT " == " INTPTR_FORMAT, p2i(*constant_addr), p2i(((address) n) + i));
4092 *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
4093 cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
4094 }
4095 }
4096
4097 //----------------------------static_subtype_check-----------------------------
4098 // Shortcut important common cases when superklass is exact:
4099 // (0) superklass is java.lang.Object (can occur in reflective code)
4100 // (1) subklass is already limited to a subtype of superklass => always ok
4101 // (2) subklass does not overlap with superklass => always fail
4102 // (3) superklass has NO subtypes and we can check with a simple compare.
4103 int Compile::static_subtype_check(ciKlass* superk, ciKlass* subk) {
4104 if (StressReflectiveCode || superk == NULL || subk == NULL) {
4105 return SSC_full_test; // Let caller generate the general case.
4106 }
4107
4108 if (!EnableMVT && !EnableValhalla && superk == env()->Object_klass()) {
4109 return SSC_always_true; // (0) this test cannot fail
4110 }
4111
4112 ciType* superelem = superk;
4113 if (superelem->is_array_klass())
4114 superelem = superelem->as_array_klass()->base_element_type();
4115
4116 if (!subk->is_interface()) { // cannot trust static interface types yet
4117 if (subk->is_subtype_of(superk)) {
4118 return SSC_always_true; // (1) false path dead; no dynamic test needed
4119 }
4120 if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
4121 !superk->is_subtype_of(subk)) {
4122 return SSC_always_false;
4123 }
4124 }
4125
4126 // If casting to an instance klass, it must have no subtypes
4127 if (superk->is_interface()) {
4128 // Cannot trust interfaces yet.
4129 // %%% S.B. superk->nof_implementors() == 1
4130 } else if (superelem->is_instance_klass()) {
4131 ciInstanceKlass* ik = superelem->as_instance_klass();
4132 if (!ik->has_subklass() && !ik->is_interface()) {
4133 if (!ik->is_final()) {
4134 // Add a dependency if there is a chance of a later subclass.
4135 dependencies()->assert_leaf_type(ik);
4136 }
4137 return SSC_easy_test; // (3) caller can do a simple ptr comparison
4138 }
4139 } else {
4140 // A primitive array type has no subtypes.
4141 return SSC_easy_test; // (3) caller can do a simple ptr comparison
4142 }
4143
4144 return SSC_full_test;
4145 }
4146
4147 Node* Compile::conv_I2X_index(PhaseGVN* phase, Node* idx, const TypeInt* sizetype, Node* ctrl) {
4148 #ifdef _LP64
4149 // The scaled index operand to AddP must be a clean 64-bit value.
4150 // Java allows a 32-bit int to be incremented to a negative
4151 // value, which appears in a 64-bit register as a large
4152 // positive number. Using that large positive number as an
4153 // operand in pointer arithmetic has bad consequences.
4154 // On the other hand, 32-bit overflow is rare, and the possibility
4155 // can often be excluded, if we annotate the ConvI2L node with
4156 // a type assertion that its value is known to be a small positive
4157 // number. (The prior range check has ensured this.)
4158 // This assertion is used by ConvI2LNode::Ideal.
4159 int index_max = max_jint - 1; // array size is max_jint, index is one less
4160 if (sizetype != NULL) index_max = sizetype->_hi - 1;
4161 const TypeInt* iidxtype = TypeInt::make(0, index_max, Type::WidenMax);
4162 idx = constrained_convI2L(phase, idx, iidxtype, ctrl);
4163 #endif
4164 return idx;
4165 }
4166
4167 // Convert integer value to a narrowed long type dependent on ctrl (for example, a range check)
4168 Node* Compile::constrained_convI2L(PhaseGVN* phase, Node* value, const TypeInt* itype, Node* ctrl) {
4169 if (ctrl != NULL) {
4170 // Express control dependency by a CastII node with a narrow type.
4171 value = new CastIINode(value, itype, false, true /* range check dependency */);
4172 // Make the CastII node dependent on the control input to prevent the narrowed ConvI2L
4173 // node from floating above the range check during loop optimizations. Otherwise, the
4174 // ConvI2L node may be eliminated independently of the range check, causing the data path
4175 // to become TOP while the control path is still there (although it's unreachable).
4176 value->set_req(0, ctrl);
4177 // Save CastII node to remove it after loop optimizations.
4178 phase->C->add_range_check_cast(value);
4179 value = phase->transform(value);
4180 }
4181 const TypeLong* ltype = TypeLong::make(itype->_lo, itype->_hi, itype->_widen);
4182 return phase->transform(new ConvI2LNode(value, ltype));
4183 }
4184
4185 // The message about the current inlining is accumulated in
4186 // _print_inlining_stream and transfered into the _print_inlining_list
4187 // once we know whether inlining succeeds or not. For regular
4188 // inlining, messages are appended to the buffer pointed by
4189 // _print_inlining_idx in the _print_inlining_list. For late inlining,
4190 // a new buffer is added after _print_inlining_idx in the list. This
4191 // way we can update the inlining message for late inlining call site
4192 // when the inlining is attempted again.
4193 void Compile::print_inlining_init() {
4194 if (print_inlining() || print_intrinsics()) {
4195 _print_inlining_stream = new stringStream();
4196 _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
4197 }
4198 }
4199
4200 void Compile::print_inlining_reinit() {
4201 if (print_inlining() || print_intrinsics()) {
4202 // Re allocate buffer when we change ResourceMark
4203 _print_inlining_stream = new stringStream();
4204 }
4205 }
4206
4207 void Compile::print_inlining_reset() {
4208 _print_inlining_stream->reset();
4209 }
4210
4211 void Compile::print_inlining_commit() {
4212 assert(print_inlining() || print_intrinsics(), "PrintInlining off?");
4213 // Transfer the message from _print_inlining_stream to the current
4214 // _print_inlining_list buffer and clear _print_inlining_stream.
4215 _print_inlining_list->at(_print_inlining_idx).ss()->write(_print_inlining_stream->as_string(), _print_inlining_stream->size());
4216 print_inlining_reset();
4217 }
4218
4219 void Compile::print_inlining_push() {
4220 // Add new buffer to the _print_inlining_list at current position
4221 _print_inlining_idx++;
4222 _print_inlining_list->insert_before(_print_inlining_idx, PrintInliningBuffer());
4223 }
4224
4225 Compile::PrintInliningBuffer& Compile::print_inlining_current() {
4226 return _print_inlining_list->at(_print_inlining_idx);
4227 }
4228
4229 void Compile::print_inlining_update(CallGenerator* cg) {
4230 if (print_inlining() || print_intrinsics()) {
4231 if (!cg->is_late_inline()) {
4232 if (print_inlining_current().cg() != NULL) {
4233 print_inlining_push();
4234 }
4235 print_inlining_commit();
4236 } else {
4237 if (print_inlining_current().cg() != cg &&
4238 (print_inlining_current().cg() != NULL ||
4239 print_inlining_current().ss()->size() != 0)) {
4240 print_inlining_push();
4241 }
4242 print_inlining_commit();
4243 print_inlining_current().set_cg(cg);
4244 }
4245 }
4246 }
4247
4248 void Compile::print_inlining_move_to(CallGenerator* cg) {
4249 // We resume inlining at a late inlining call site. Locate the
4250 // corresponding inlining buffer so that we can update it.
4251 if (print_inlining()) {
4252 for (int i = 0; i < _print_inlining_list->length(); i++) {
4253 if (_print_inlining_list->adr_at(i)->cg() == cg) {
4254 _print_inlining_idx = i;
4255 return;
4256 }
4257 }
4258 ShouldNotReachHere();
4259 }
4260 }
4261
4262 void Compile::print_inlining_update_delayed(CallGenerator* cg) {
4263 if (print_inlining()) {
4264 assert(_print_inlining_stream->size() > 0, "missing inlining msg");
4265 assert(print_inlining_current().cg() == cg, "wrong entry");
4266 // replace message with new message
4267 _print_inlining_list->at_put(_print_inlining_idx, PrintInliningBuffer());
4268 print_inlining_commit();
4269 print_inlining_current().set_cg(cg);
4270 }
4271 }
4272
4273 void Compile::print_inlining_assert_ready() {
4274 assert(!_print_inlining || _print_inlining_stream->size() == 0, "loosing data");
4275 }
4276
4277 void Compile::process_print_inlining() {
4278 bool do_print_inlining = print_inlining() || print_intrinsics();
4279 if (do_print_inlining || log() != NULL) {
4280 // Print inlining message for candidates that we couldn't inline
4281 // for lack of space
4282 for (int i = 0; i < _late_inlines.length(); i++) {
4283 CallGenerator* cg = _late_inlines.at(i);
4284 if (!cg->is_mh_late_inline()) {
4285 const char* msg = "live nodes > LiveNodeCountInliningCutoff";
4286 if (do_print_inlining) {
4287 cg->print_inlining_late(msg);
4288 }
4289 log_late_inline_failure(cg, msg);
4290 }
4291 }
4292 }
4293 if (do_print_inlining) {
4294 ResourceMark rm;
4295 stringStream ss;
4296 for (int i = 0; i < _print_inlining_list->length(); i++) {
4297 ss.print("%s", _print_inlining_list->adr_at(i)->ss()->as_string());
4298 }
4299 size_t end = ss.size();
4300 _print_inlining_output = NEW_ARENA_ARRAY(comp_arena(), char, end+1);
4301 strncpy(_print_inlining_output, ss.base(), end+1);
4302 _print_inlining_output[end] = 0;
4303 }
4304 }
4305
4306 void Compile::dump_print_inlining() {
4307 if (_print_inlining_output != NULL) {
4308 tty->print_raw(_print_inlining_output);
4309 }
4310 }
4311
4312 void Compile::log_late_inline(CallGenerator* cg) {
4313 if (log() != NULL) {
4314 log()->head("late_inline method='%d' inline_id='" JLONG_FORMAT "'", log()->identify(cg->method()),
4315 cg->unique_id());
4316 JVMState* p = cg->call_node()->jvms();
4317 while (p != NULL) {
4318 log()->elem("jvms bci='%d' method='%d'", p->bci(), log()->identify(p->method()));
4319 p = p->caller();
4320 }
4321 log()->tail("late_inline");
4322 }
4323 }
4324
4325 void Compile::log_late_inline_failure(CallGenerator* cg, const char* msg) {
4326 log_late_inline(cg);
4327 if (log() != NULL) {
4328 log()->inline_fail(msg);
4329 }
4330 }
4331
4332 void Compile::log_inline_id(CallGenerator* cg) {
4333 if (log() != NULL) {
4334 // The LogCompilation tool needs a unique way to identify late
4335 // inline call sites. This id must be unique for this call site in
4336 // this compilation. Try to have it unique across compilations as
4337 // well because it can be convenient when grepping through the log
4338 // file.
4339 // Distinguish OSR compilations from others in case CICountOSR is
4340 // on.
4341 jlong id = ((jlong)unique()) + (((jlong)compile_id()) << 33) + (CICountOSR && is_osr_compilation() ? ((jlong)1) << 32 : 0);
4342 cg->set_unique_id(id);
4343 log()->elem("inline_id id='" JLONG_FORMAT "'", id);
4344 }
4345 }
4346
4347 void Compile::log_inline_failure(const char* msg) {
4348 if (C->log() != NULL) {
4349 C->log()->inline_fail(msg);
4350 }
4351 }
4352
4353
4354 // Dump inlining replay data to the stream.
4355 // Don't change thread state and acquire any locks.
4356 void Compile::dump_inline_data(outputStream* out) {
4357 InlineTree* inl_tree = ilt();
4358 if (inl_tree != NULL) {
4359 out->print(" inline %d", inl_tree->count());
4360 inl_tree->dump_replay_data(out);
4361 }
4362 }
4363
4364 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
4365 if (n1->Opcode() < n2->Opcode()) return -1;
4366 else if (n1->Opcode() > n2->Opcode()) return 1;
4367
4368 assert(n1->req() == n2->req(), "can't compare %s nodes: n1->req() = %d, n2->req() = %d", NodeClassNames[n1->Opcode()], n1->req(), n2->req());
4369 for (uint i = 1; i < n1->req(); i++) {
4370 if (n1->in(i) < n2->in(i)) return -1;
4371 else if (n1->in(i) > n2->in(i)) return 1;
4372 }
4373
4374 return 0;
4375 }
4376
4377 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
4378 Node* n1 = *n1p;
4379 Node* n2 = *n2p;
4380
4381 return cmp_expensive_nodes(n1, n2);
4382 }
4383
4384 void Compile::sort_expensive_nodes() {
4385 if (!expensive_nodes_sorted()) {
4386 _expensive_nodes->sort(cmp_expensive_nodes);
4387 }
4388 }
4389
4390 bool Compile::expensive_nodes_sorted() const {
4391 for (int i = 1; i < _expensive_nodes->length(); i++) {
4392 if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
4393 return false;
4394 }
4395 }
4396 return true;
4397 }
4398
4399 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
4400 if (_expensive_nodes->length() == 0) {
4401 return false;
4402 }
4403
4404 assert(OptimizeExpensiveOps, "optimization off?");
4405
4406 // Take this opportunity to remove dead nodes from the list
4407 int j = 0;
4408 for (int i = 0; i < _expensive_nodes->length(); i++) {
4409 Node* n = _expensive_nodes->at(i);
4410 if (!n->is_unreachable(igvn)) {
4411 assert(n->is_expensive(), "should be expensive");
4412 _expensive_nodes->at_put(j, n);
4413 j++;
4414 }
4415 }
4416 _expensive_nodes->trunc_to(j);
4417
4418 // Then sort the list so that similar nodes are next to each other
4419 // and check for at least two nodes of identical kind with same data
4420 // inputs.
4421 sort_expensive_nodes();
4422
4423 for (int i = 0; i < _expensive_nodes->length()-1; i++) {
4424 if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
4425 return true;
4426 }
4427 }
4428
4429 return false;
4430 }
4431
4432 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
4433 if (_expensive_nodes->length() == 0) {
4434 return;
4435 }
4436
4437 assert(OptimizeExpensiveOps, "optimization off?");
4438
4439 // Sort to bring similar nodes next to each other and clear the
4440 // control input of nodes for which there's only a single copy.
4441 sort_expensive_nodes();
4442
4443 int j = 0;
4444 int identical = 0;
4445 int i = 0;
4446 bool modified = false;
4447 for (; i < _expensive_nodes->length()-1; i++) {
4448 assert(j <= i, "can't write beyond current index");
4449 if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
4450 identical++;
4451 _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4452 continue;
4453 }
4454 if (identical > 0) {
4455 _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4456 identical = 0;
4457 } else {
4458 Node* n = _expensive_nodes->at(i);
4459 igvn.replace_input_of(n, 0, NULL);
4460 igvn.hash_insert(n);
4461 modified = true;
4462 }
4463 }
4464 if (identical > 0) {
4465 _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4466 } else if (_expensive_nodes->length() >= 1) {
4467 Node* n = _expensive_nodes->at(i);
4468 igvn.replace_input_of(n, 0, NULL);
4469 igvn.hash_insert(n);
4470 modified = true;
4471 }
4472 _expensive_nodes->trunc_to(j);
4473 if (modified) {
4474 igvn.optimize();
4475 }
4476 }
4477
4478 void Compile::add_expensive_node(Node * n) {
4479 assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
4480 assert(n->is_expensive(), "expensive nodes with non-null control here only");
4481 assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
4482 if (OptimizeExpensiveOps) {
4483 _expensive_nodes->append(n);
4484 } else {
4485 // Clear control input and let IGVN optimize expensive nodes if
4486 // OptimizeExpensiveOps is off.
4487 n->set_req(0, NULL);
4488 }
4489 }
4490
4491 /**
4492 * Remove the speculative part of types and clean up the graph
4493 */
4494 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
4495 if (UseTypeSpeculation) {
4496 Unique_Node_List worklist;
4497 worklist.push(root());
4498 int modified = 0;
4499 // Go over all type nodes that carry a speculative type, drop the
4500 // speculative part of the type and enqueue the node for an igvn
4501 // which may optimize it out.
4502 for (uint next = 0; next < worklist.size(); ++next) {
4503 Node *n = worklist.at(next);
4504 if (n->is_Type()) {
4505 TypeNode* tn = n->as_Type();
4506 const Type* t = tn->type();
4507 const Type* t_no_spec = t->remove_speculative();
4508 if (t_no_spec != t) {
4509 bool in_hash = igvn.hash_delete(n);
4510 assert(in_hash, "node should be in igvn hash table");
4511 tn->set_type(t_no_spec);
4512 igvn.hash_insert(n);
4513 igvn._worklist.push(n); // give it a chance to go away
4514 modified++;
4515 }
4516 }
4517 uint max = n->len();
4518 for( uint i = 0; i < max; ++i ) {
4519 Node *m = n->in(i);
4520 if (not_a_node(m)) continue;
4521 worklist.push(m);
4522 }
4523 }
4524 // Drop the speculative part of all types in the igvn's type table
4525 igvn.remove_speculative_types();
4526 if (modified > 0) {
4527 igvn.optimize();
4528 }
4529 #ifdef ASSERT
4530 // Verify that after the IGVN is over no speculative type has resurfaced
4531 worklist.clear();
4532 worklist.push(root());
4533 for (uint next = 0; next < worklist.size(); ++next) {
4534 Node *n = worklist.at(next);
4535 const Type* t = igvn.type_or_null(n);
4536 assert((t == NULL) || (t == t->remove_speculative()), "no more speculative types");
4537 if (n->is_Type()) {
4538 t = n->as_Type()->type();
4539 assert(t == t->remove_speculative(), "no more speculative types");
4540 }
4541 uint max = n->len();
4542 for( uint i = 0; i < max; ++i ) {
4543 Node *m = n->in(i);
4544 if (not_a_node(m)) continue;
4545 worklist.push(m);
4546 }
4547 }
4548 igvn.check_no_speculative_types();
4549 #endif
4550 }
4551 }
4552
4553 // Auxiliary method to support randomized stressing/fuzzing.
4554 //
4555 // This method can be called the arbitrary number of times, with current count
4556 // as the argument. The logic allows selecting a single candidate from the
4557 // running list of candidates as follows:
4558 // int count = 0;
4559 // Cand* selected = null;
4560 // while(cand = cand->next()) {
4561 // if (randomized_select(++count)) {
4562 // selected = cand;
4563 // }
4564 // }
4565 //
4566 // Including count equalizes the chances any candidate is "selected".
4567 // This is useful when we don't have the complete list of candidates to choose
4568 // from uniformly. In this case, we need to adjust the randomicity of the
4569 // selection, or else we will end up biasing the selection towards the latter
4570 // candidates.
4571 //
4572 // Quick back-envelope calculation shows that for the list of n candidates
4573 // the equal probability for the candidate to persist as "best" can be
4574 // achieved by replacing it with "next" k-th candidate with the probability
4575 // of 1/k. It can be easily shown that by the end of the run, the
4576 // probability for any candidate is converged to 1/n, thus giving the
4577 // uniform distribution among all the candidates.
4578 //
4579 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
4580 #define RANDOMIZED_DOMAIN_POW 29
4581 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
4582 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
4583 bool Compile::randomized_select(int count) {
4584 assert(count > 0, "only positive");
4585 return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);
4586 }
4587
4588 CloneMap& Compile::clone_map() { return _clone_map; }
4589 void Compile::set_clone_map(Dict* d) { _clone_map._dict = d; }
4590
4591 void NodeCloneInfo::dump() const {
4592 tty->print(" {%d:%d} ", idx(), gen());
4593 }
4594
4595 void CloneMap::clone(Node* old, Node* nnn, int gen) {
4596 uint64_t val = value(old->_idx);
4597 NodeCloneInfo cio(val);
4598 assert(val != 0, "old node should be in the map");
4599 NodeCloneInfo cin(cio.idx(), gen + cio.gen());
4600 insert(nnn->_idx, cin.get());
4601 #ifndef PRODUCT
4602 if (is_debug()) {
4603 tty->print_cr("CloneMap::clone inserted node %d info {%d:%d} into CloneMap", nnn->_idx, cin.idx(), cin.gen());
4604 }
4605 #endif
4606 }
4607
4608 void CloneMap::verify_insert_and_clone(Node* old, Node* nnn, int gen) {
4609 NodeCloneInfo cio(value(old->_idx));
4610 if (cio.get() == 0) {
4611 cio.set(old->_idx, 0);
4612 insert(old->_idx, cio.get());
4613 #ifndef PRODUCT
4614 if (is_debug()) {
4615 tty->print_cr("CloneMap::verify_insert_and_clone inserted node %d info {%d:%d} into CloneMap", old->_idx, cio.idx(), cio.gen());
4616 }
4617 #endif
4618 }
4619 clone(old, nnn, gen);
4620 }
4621
4622 int CloneMap::max_gen() const {
4623 int g = 0;
4624 DictI di(_dict);
4625 for(; di.test(); ++di) {
4626 int t = gen(di._key);
4627 if (g < t) {
4628 g = t;
4629 #ifndef PRODUCT
4630 if (is_debug()) {
4631 tty->print_cr("CloneMap::max_gen() update max=%d from %d", g, _2_node_idx_t(di._key));
4632 }
4633 #endif
4634 }
4635 }
4636 return g;
4637 }
4638
4639 void CloneMap::dump(node_idx_t key) const {
4640 uint64_t val = value(key);
4641 if (val != 0) {
4642 NodeCloneInfo ni(val);
4643 ni.dump();
4644 }
4645 }
4646
4647 // Helper function for enforcing certain bytecodes to reexecute if
4648 // deoptimization happens
4649 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
4650 ciMethod* cur_method = jvms->method();
4651 int cur_bci = jvms->bci();
4652 if (cur_method != NULL && cur_bci != InvocationEntryBci) {
4653 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
4654 return Interpreter::bytecode_should_reexecute(code) ||
4655 (is_anewarray && (code == Bytecodes::_multianewarray));
4656 // Reexecute _multianewarray bytecode which was replaced with
4657 // sequence of [a]newarray. See Parse::do_multianewarray().
4658 //
4659 // Note: interpreter should not have it set since this optimization
4660 // is limited by dimensions and guarded by flag so in some cases
4661 // multianewarray() runtime calls will be generated and
4662 // the bytecode should not be reexecutes (stack will not be reset).
4663 } else
4664 return false;
4665 }
4666
4667 void Compile::add_safepoint_edges(SafePointNode* call, JVMState* youngest_jvms, bool can_prune_locals, uint stack_slots_not_pruned) {
4668 // do not scribble on the input jvms
4669 JVMState* out_jvms = youngest_jvms->clone_deep(C);
4670 call->set_jvms(out_jvms); // Start jvms list for call node
4671
4672 // For a known set of bytecodes, the interpreter should reexecute them if
4673 // deoptimization happens. We set the reexecute state for them here
4674 if (out_jvms->is_reexecute_undefined() && //don't change if already specified
4675 should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
4676 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
4677 }
4678
4679 // Presize the call:
4680 DEBUG_ONLY(uint non_debug_edges = call->req());
4681 call->add_req_batch(top(), youngest_jvms->debug_depth());
4682 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
4683
4684 // Set up edges so that the call looks like this:
4685 // Call [state:] ctl io mem fptr retadr
4686 // [parms:] parm0 ... parmN
4687 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
4688 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
4689 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
4690 // Note that caller debug info precedes callee debug info.
4691
4692 // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
4693 uint debug_ptr = call->req();
4694
4695 // Loop over the map input edges associated with jvms, add them
4696 // to the call node, & reset all offsets to match call node array.
4697 for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
4698 uint debug_end = debug_ptr;
4699 uint debug_start = debug_ptr - in_jvms->debug_size();
4700 debug_ptr = debug_start; // back up the ptr
4701
4702 uint p = debug_start; // walks forward in [debug_start, debug_end)
4703 uint j, k, l;
4704 SafePointNode* in_map = in_jvms->map();
4705 out_jvms->set_map(call);
4706
4707 if (can_prune_locals) {
4708 assert(in_jvms->method() == out_jvms->method(), "sanity");
4709 // If the current throw can reach an exception handler in this JVMS,
4710 // then we must keep everything live that can reach that handler.
4711 // As a quick and dirty approximation, we look for any handlers at all.
4712 if (in_jvms->method()->has_exception_handlers()) {
4713 can_prune_locals = false;
4714 }
4715 }
4716
4717 // Add the Locals
4718 k = in_jvms->locoff();
4719 l = in_jvms->loc_size();
4720 out_jvms->set_locoff(p);
4721 if (!can_prune_locals) {
4722 for (j = 0; j < l; j++)
4723 call->set_req(p++, in_map->in(k+j));
4724 } else {
4725 p += l; // already set to top above by add_req_batch
4726 }
4727
4728 // Add the Expression Stack
4729 k = in_jvms->stkoff();
4730 l = in_jvms->sp();
4731 out_jvms->set_stkoff(p);
4732 if (!can_prune_locals) {
4733 for (j = 0; j < l; j++)
4734 call->set_req(p++, in_map->in(k+j));
4735 } else if (can_prune_locals && stack_slots_not_pruned != 0) {
4736 // Divide stack into {S0,...,S1}, where S0 is set to top.
4737 uint s1 = stack_slots_not_pruned;
4738 stack_slots_not_pruned = 0; // for next iteration
4739 if (s1 > l) s1 = l;
4740 uint s0 = l - s1;
4741 p += s0; // skip the tops preinstalled by add_req_batch
4742 for (j = s0; j < l; j++)
4743 call->set_req(p++, in_map->in(k+j));
4744 } else {
4745 p += l; // already set to top above by add_req_batch
4746 }
4747
4748 // Add the Monitors
4749 k = in_jvms->monoff();
4750 l = in_jvms->mon_size();
4751 out_jvms->set_monoff(p);
4752 for (j = 0; j < l; j++)
4753 call->set_req(p++, in_map->in(k+j));
4754
4755 // Copy any scalar object fields.
4756 k = in_jvms->scloff();
4757 l = in_jvms->scl_size();
4758 out_jvms->set_scloff(p);
4759 for (j = 0; j < l; j++)
4760 call->set_req(p++, in_map->in(k+j));
4761
4762 // Finish the new jvms.
4763 out_jvms->set_endoff(p);
4764
4765 assert(out_jvms->endoff() == debug_end, "fill ptr must match");
4766 assert(out_jvms->depth() == in_jvms->depth(), "depth must match");
4767 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match");
4768 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match");
4769 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match");
4770 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
4771
4772 // Update the two tail pointers in parallel.
4773 out_jvms = out_jvms->caller();
4774 in_jvms = in_jvms->caller();
4775 }
4776
4777 assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
4778
4779 // Test the correctness of JVMState::debug_xxx accessors:
4780 assert(call->jvms()->debug_start() == non_debug_edges, "");
4781 assert(call->jvms()->debug_end() == call->req(), "");
4782 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
4783 }