1 /*
2 * Copyright (c) 1997, 2010, 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 "incls/_precompiled.incl"
26 #include "incls/_compile.cpp.incl"
27
28
29 // -------------------- Compile::mach_constant_base_node -----------------------
30 // Constant table base node singleton.
31 MachConstantBaseNode* Compile::mach_constant_base_node() {
32 if (_mach_constant_base_node == NULL) {
33 _mach_constant_base_node = new (C) MachConstantBaseNode();
34 _mach_constant_base_node->set_req(0, C->root());
35 }
36 return _mach_constant_base_node;
37 }
38
39
40 /// Support for intrinsics.
41
42 // Return the index at which m must be inserted (or already exists).
43 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
44 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual) {
45 #ifdef ASSERT
46 for (int i = 1; i < _intrinsics->length(); i++) {
47 CallGenerator* cg1 = _intrinsics->at(i-1);
48 CallGenerator* cg2 = _intrinsics->at(i);
49 assert(cg1->method() != cg2->method()
50 ? cg1->method() < cg2->method()
51 : cg1->is_virtual() < cg2->is_virtual(),
52 "compiler intrinsics list must stay sorted");
53 }
54 #endif
55 // Binary search sorted list, in decreasing intervals [lo, hi].
56 int lo = 0, hi = _intrinsics->length()-1;
57 while (lo <= hi) {
58 int mid = (uint)(hi + lo) / 2;
59 ciMethod* mid_m = _intrinsics->at(mid)->method();
60 if (m < mid_m) {
61 hi = mid-1;
62 } else if (m > mid_m) {
63 lo = mid+1;
64 } else {
65 // look at minor sort key
66 bool mid_virt = _intrinsics->at(mid)->is_virtual();
67 if (is_virtual < mid_virt) {
68 hi = mid-1;
69 } else if (is_virtual > mid_virt) {
70 lo = mid+1;
71 } else {
72 return mid; // exact match
73 }
74 }
75 }
76 return lo; // inexact match
77 }
78
79 void Compile::register_intrinsic(CallGenerator* cg) {
80 if (_intrinsics == NULL) {
81 _intrinsics = new GrowableArray<CallGenerator*>(60);
82 }
83 // This code is stolen from ciObjectFactory::insert.
84 // Really, GrowableArray should have methods for
85 // insert_at, remove_at, and binary_search.
86 int len = _intrinsics->length();
87 int index = intrinsic_insertion_index(cg->method(), cg->is_virtual());
88 if (index == len) {
89 _intrinsics->append(cg);
90 } else {
91 #ifdef ASSERT
92 CallGenerator* oldcg = _intrinsics->at(index);
93 assert(oldcg->method() != cg->method() || oldcg->is_virtual() != cg->is_virtual(), "don't register twice");
94 #endif
95 _intrinsics->append(_intrinsics->at(len-1));
96 int pos;
97 for (pos = len-2; pos >= index; pos--) {
98 _intrinsics->at_put(pos+1,_intrinsics->at(pos));
99 }
100 _intrinsics->at_put(index, cg);
101 }
102 assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
103 }
104
105 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
106 assert(m->is_loaded(), "don't try this on unloaded methods");
107 if (_intrinsics != NULL) {
108 int index = intrinsic_insertion_index(m, is_virtual);
109 if (index < _intrinsics->length()
110 && _intrinsics->at(index)->method() == m
111 && _intrinsics->at(index)->is_virtual() == is_virtual) {
112 return _intrinsics->at(index);
113 }
114 }
115 // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
116 if (m->intrinsic_id() != vmIntrinsics::_none &&
117 m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
118 CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
119 if (cg != NULL) {
120 // Save it for next time:
121 register_intrinsic(cg);
122 return cg;
123 } else {
124 gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
125 }
126 }
127 return NULL;
128 }
129
130 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
131 // in library_call.cpp.
132
133
134 #ifndef PRODUCT
135 // statistics gathering...
136
137 juint Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
138 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
139
140 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
141 assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
142 int oflags = _intrinsic_hist_flags[id];
143 assert(flags != 0, "what happened?");
144 if (is_virtual) {
145 flags |= _intrinsic_virtual;
146 }
147 bool changed = (flags != oflags);
148 if ((flags & _intrinsic_worked) != 0) {
149 juint count = (_intrinsic_hist_count[id] += 1);
150 if (count == 1) {
151 changed = true; // first time
152 }
153 // increment the overall count also:
154 _intrinsic_hist_count[vmIntrinsics::_none] += 1;
155 }
156 if (changed) {
157 if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
158 // Something changed about the intrinsic's virtuality.
159 if ((flags & _intrinsic_virtual) != 0) {
160 // This is the first use of this intrinsic as a virtual call.
161 if (oflags != 0) {
162 // We already saw it as a non-virtual, so note both cases.
163 flags |= _intrinsic_both;
164 }
165 } else if ((oflags & _intrinsic_both) == 0) {
166 // This is the first use of this intrinsic as a non-virtual
167 flags |= _intrinsic_both;
168 }
169 }
170 _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
171 }
172 // update the overall flags also:
173 _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
174 return changed;
175 }
176
177 static char* format_flags(int flags, char* buf) {
178 buf[0] = 0;
179 if ((flags & Compile::_intrinsic_worked) != 0) strcat(buf, ",worked");
180 if ((flags & Compile::_intrinsic_failed) != 0) strcat(buf, ",failed");
181 if ((flags & Compile::_intrinsic_disabled) != 0) strcat(buf, ",disabled");
182 if ((flags & Compile::_intrinsic_virtual) != 0) strcat(buf, ",virtual");
183 if ((flags & Compile::_intrinsic_both) != 0) strcat(buf, ",nonvirtual");
184 if (buf[0] == 0) strcat(buf, ",");
185 assert(buf[0] == ',', "must be");
186 return &buf[1];
187 }
188
189 void Compile::print_intrinsic_statistics() {
190 char flagsbuf[100];
191 ttyLocker ttyl;
192 if (xtty != NULL) xtty->head("statistics type='intrinsic'");
193 tty->print_cr("Compiler intrinsic usage:");
194 juint total = _intrinsic_hist_count[vmIntrinsics::_none];
195 if (total == 0) total = 1; // avoid div0 in case of no successes
196 #define PRINT_STAT_LINE(name, c, f) \
197 tty->print_cr(" %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
198 for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
199 vmIntrinsics::ID id = (vmIntrinsics::ID) index;
200 int flags = _intrinsic_hist_flags[id];
201 juint count = _intrinsic_hist_count[id];
202 if ((flags | count) != 0) {
203 PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
204 }
205 }
206 PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
207 if (xtty != NULL) xtty->tail("statistics");
208 }
209
210 void Compile::print_statistics() {
211 { ttyLocker ttyl;
212 if (xtty != NULL) xtty->head("statistics type='opto'");
213 Parse::print_statistics();
214 PhaseCCP::print_statistics();
215 PhaseRegAlloc::print_statistics();
216 Scheduling::print_statistics();
217 PhasePeephole::print_statistics();
218 PhaseIdealLoop::print_statistics();
219 if (xtty != NULL) xtty->tail("statistics");
220 }
221 if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
222 // put this under its own <statistics> element.
223 print_intrinsic_statistics();
224 }
225 }
226 #endif //PRODUCT
227
228 // Support for bundling info
229 Bundle* Compile::node_bundling(const Node *n) {
230 assert(valid_bundle_info(n), "oob");
231 return &_node_bundling_base[n->_idx];
232 }
233
234 bool Compile::valid_bundle_info(const Node *n) {
235 return (_node_bundling_limit > n->_idx);
236 }
237
238
239 void Compile::gvn_replace_by(Node* n, Node* nn) {
240 for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
241 Node* use = n->last_out(i);
242 bool is_in_table = initial_gvn()->hash_delete(use);
243 uint uses_found = 0;
244 for (uint j = 0; j < use->len(); j++) {
245 if (use->in(j) == n) {
246 if (j < use->req())
247 use->set_req(j, nn);
248 else
249 use->set_prec(j, nn);
250 uses_found++;
251 }
252 }
253 if (is_in_table) {
254 // reinsert into table
255 initial_gvn()->hash_find_insert(use);
256 }
257 record_for_igvn(use);
258 i -= uses_found; // we deleted 1 or more copies of this edge
259 }
260 }
261
262
263
264
265 // Identify all nodes that are reachable from below, useful.
266 // Use breadth-first pass that records state in a Unique_Node_List,
267 // recursive traversal is slower.
268 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
269 int estimated_worklist_size = unique();
270 useful.map( estimated_worklist_size, NULL ); // preallocate space
271
272 // Initialize worklist
273 if (root() != NULL) { useful.push(root()); }
274 // If 'top' is cached, declare it useful to preserve cached node
275 if( cached_top_node() ) { useful.push(cached_top_node()); }
276
277 // Push all useful nodes onto the list, breadthfirst
278 for( uint next = 0; next < useful.size(); ++next ) {
279 assert( next < unique(), "Unique useful nodes < total nodes");
280 Node *n = useful.at(next);
281 uint max = n->len();
282 for( uint i = 0; i < max; ++i ) {
283 Node *m = n->in(i);
284 if( m == NULL ) continue;
285 useful.push(m);
286 }
287 }
288 }
289
290 // Disconnect all useless nodes by disconnecting those at the boundary.
291 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
292 uint next = 0;
293 while( next < useful.size() ) {
294 Node *n = useful.at(next++);
295 // Use raw traversal of out edges since this code removes out edges
296 int max = n->outcnt();
297 for (int j = 0; j < max; ++j ) {
298 Node* child = n->raw_out(j);
299 if( ! useful.member(child) ) {
300 assert( !child->is_top() || child != top(),
301 "If top is cached in Compile object it is in useful list");
302 // Only need to remove this out-edge to the useless node
303 n->raw_del_out(j);
304 --j;
305 --max;
306 }
307 }
308 if (n->outcnt() == 1 && n->has_special_unique_user()) {
309 record_for_igvn( n->unique_out() );
310 }
311 }
312 debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
313 }
314
315 //------------------------------frame_size_in_words-----------------------------
316 // frame_slots in units of words
317 int Compile::frame_size_in_words() const {
318 // shift is 0 in LP32 and 1 in LP64
319 const int shift = (LogBytesPerWord - LogBytesPerInt);
320 int words = _frame_slots >> shift;
321 assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
322 return words;
323 }
324
325 // ============================================================================
326 //------------------------------CompileWrapper---------------------------------
327 class CompileWrapper : public StackObj {
328 Compile *const _compile;
329 public:
330 CompileWrapper(Compile* compile);
331
332 ~CompileWrapper();
333 };
334
335 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
336 // the Compile* pointer is stored in the current ciEnv:
337 ciEnv* env = compile->env();
338 assert(env == ciEnv::current(), "must already be a ciEnv active");
339 assert(env->compiler_data() == NULL, "compile already active?");
340 env->set_compiler_data(compile);
341 assert(compile == Compile::current(), "sanity");
342
343 compile->set_type_dict(NULL);
344 compile->set_type_hwm(NULL);
345 compile->set_type_last_size(0);
346 compile->set_last_tf(NULL, NULL);
347 compile->set_indexSet_arena(NULL);
348 compile->set_indexSet_free_block_list(NULL);
349 compile->init_type_arena();
350 Type::Initialize(compile);
351 _compile->set_scratch_buffer_blob(NULL);
352 _compile->begin_method();
353 }
354 CompileWrapper::~CompileWrapper() {
355 _compile->end_method();
356 if (_compile->scratch_buffer_blob() != NULL)
357 BufferBlob::free(_compile->scratch_buffer_blob());
358 _compile->env()->set_compiler_data(NULL);
359 }
360
361
362 //----------------------------print_compile_messages---------------------------
363 void Compile::print_compile_messages() {
364 #ifndef PRODUCT
365 // Check if recompiling
366 if (_subsume_loads == false && PrintOpto) {
367 // Recompiling without allowing machine instructions to subsume loads
368 tty->print_cr("*********************************************************");
369 tty->print_cr("** Bailout: Recompile without subsuming loads **");
370 tty->print_cr("*********************************************************");
371 }
372 if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
373 // Recompiling without escape analysis
374 tty->print_cr("*********************************************************");
375 tty->print_cr("** Bailout: Recompile without escape analysis **");
376 tty->print_cr("*********************************************************");
377 }
378 if (env()->break_at_compile()) {
379 // Open the debugger when compiling this method.
380 tty->print("### Breaking when compiling: ");
381 method()->print_short_name();
382 tty->cr();
383 BREAKPOINT;
384 }
385
386 if( PrintOpto ) {
387 if (is_osr_compilation()) {
388 tty->print("[OSR]%3d", _compile_id);
389 } else {
390 tty->print("%3d", _compile_id);
391 }
392 }
393 #endif
394 }
395
396
397 void Compile::init_scratch_buffer_blob(int const_size) {
398 if (scratch_buffer_blob() != NULL) return;
399
400 // Construct a temporary CodeBuffer to have it construct a BufferBlob
401 // Cache this BufferBlob for this compile.
402 ResourceMark rm;
403 _scratch_const_size = const_size;
404 int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
405 BufferBlob* blob = BufferBlob::create("Compile::scratch_buffer", size);
406 // Record the buffer blob for next time.
407 set_scratch_buffer_blob(blob);
408 // Have we run out of code space?
409 if (scratch_buffer_blob() == NULL) {
410 // Let CompilerBroker disable further compilations.
411 record_failure("Not enough space for scratch buffer in CodeCache");
412 return;
413 }
414
415 // Initialize the relocation buffers
416 relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
417 set_scratch_locs_memory(locs_buf);
418 }
419
420
421 void Compile::clear_scratch_buffer_blob() {
422 assert(scratch_buffer_blob(), "no BufferBlob set");
423 set_scratch_buffer_blob(NULL);
424 set_scratch_locs_memory(NULL);
425 }
426
427
428 //-----------------------scratch_emit_size-------------------------------------
429 // Helper function that computes size by emitting code
430 uint Compile::scratch_emit_size(const Node* n) {
431 // Start scratch_emit_size section.
432 set_in_scratch_emit_size(true);
433
434 // Emit into a trash buffer and count bytes emitted.
435 // This is a pretty expensive way to compute a size,
436 // but it works well enough if seldom used.
437 // All common fixed-size instructions are given a size
438 // method by the AD file.
439 // Note that the scratch buffer blob and locs memory are
440 // allocated at the beginning of the compile task, and
441 // may be shared by several calls to scratch_emit_size.
442 // The allocation of the scratch buffer blob is particularly
443 // expensive, since it has to grab the code cache lock.
444 BufferBlob* blob = this->scratch_buffer_blob();
445 assert(blob != NULL, "Initialize BufferBlob at start");
446 assert(blob->size() > MAX_inst_size, "sanity");
447 relocInfo* locs_buf = scratch_locs_memory();
448 address blob_begin = blob->content_begin();
449 address blob_end = (address)locs_buf;
450 assert(blob->content_contains(blob_end), "sanity");
451 CodeBuffer buf(blob_begin, blob_end - blob_begin);
452 buf.initialize_consts_size(_scratch_const_size);
453 buf.initialize_stubs_size(MAX_stubs_size);
454 assert(locs_buf != NULL, "sanity");
455 int lsize = MAX_locs_size / 3;
456 buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
457 buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
458 buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
459
460 // Do the emission.
461 n->emit(buf, this->regalloc());
462
463 // End scratch_emit_size section.
464 set_in_scratch_emit_size(false);
465
466 return buf.insts_size();
467 }
468
469
470 // ============================================================================
471 //------------------------------Compile standard-------------------------------
472 debug_only( int Compile::_debug_idx = 100000; )
473
474 // Compile a method. entry_bci is -1 for normal compilations and indicates
475 // the continuation bci for on stack replacement.
476
477
478 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci, bool subsume_loads, bool do_escape_analysis )
479 : Phase(Compiler),
480 _env(ci_env),
481 _log(ci_env->log()),
482 _compile_id(ci_env->compile_id()),
483 _save_argument_registers(false),
484 _stub_name(NULL),
485 _stub_function(NULL),
486 _stub_entry_point(NULL),
487 _method(target),
488 _entry_bci(osr_bci),
489 _initial_gvn(NULL),
490 _for_igvn(NULL),
491 _warm_calls(NULL),
492 _subsume_loads(subsume_loads),
493 _do_escape_analysis(do_escape_analysis),
494 _failure_reason(NULL),
495 _code_buffer("Compile::Fill_buffer"),
496 _orig_pc_slot(0),
497 _orig_pc_slot_offset_in_bytes(0),
498 _has_method_handle_invokes(false),
499 _mach_constant_base_node(NULL),
500 _node_bundling_limit(0),
501 _node_bundling_base(NULL),
502 _java_calls(0),
503 _inner_loops(0),
504 _scratch_const_size(-1),
505 _in_scratch_emit_size(false),
506 #ifndef PRODUCT
507 _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
508 _printer(IdealGraphPrinter::printer()),
509 #endif
510 _congraph(NULL) {
511 C = this;
512
513 CompileWrapper cw(this);
514 #ifndef PRODUCT
515 if (TimeCompiler2) {
516 tty->print(" ");
517 target->holder()->name()->print();
518 tty->print(".");
519 target->print_short_name();
520 tty->print(" ");
521 }
522 TraceTime t1("Total compilation time", &_t_totalCompilation, TimeCompiler, TimeCompiler2);
523 TraceTime t2(NULL, &_t_methodCompilation, TimeCompiler, false);
524 bool print_opto_assembly = PrintOptoAssembly || _method->has_option("PrintOptoAssembly");
525 if (!print_opto_assembly) {
526 bool print_assembly = (PrintAssembly || _method->should_print_assembly());
527 if (print_assembly && !Disassembler::can_decode()) {
528 tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
529 print_opto_assembly = true;
530 }
531 }
532 set_print_assembly(print_opto_assembly);
533 set_parsed_irreducible_loop(false);
534 #endif
535
536 if (ProfileTraps) {
537 // Make sure the method being compiled gets its own MDO,
538 // so we can at least track the decompile_count().
539 method()->build_method_data();
540 }
541
542 Init(::AliasLevel);
543
544
545 print_compile_messages();
546
547 if (UseOldInlining || PrintCompilation NOT_PRODUCT( || PrintOpto) )
548 _ilt = InlineTree::build_inline_tree_root();
549 else
550 _ilt = NULL;
551
552 // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
553 assert(num_alias_types() >= AliasIdxRaw, "");
554
555 #define MINIMUM_NODE_HASH 1023
556 // Node list that Iterative GVN will start with
557 Unique_Node_List for_igvn(comp_arena());
558 set_for_igvn(&for_igvn);
559
560 // GVN that will be run immediately on new nodes
561 uint estimated_size = method()->code_size()*4+64;
562 estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
563 PhaseGVN gvn(node_arena(), estimated_size);
564 set_initial_gvn(&gvn);
565
566 { // Scope for timing the parser
567 TracePhase t3("parse", &_t_parser, true);
568
569 // Put top into the hash table ASAP.
570 initial_gvn()->transform_no_reclaim(top());
571
572 // Set up tf(), start(), and find a CallGenerator.
573 CallGenerator* cg;
574 if (is_osr_compilation()) {
575 const TypeTuple *domain = StartOSRNode::osr_domain();
576 const TypeTuple *range = TypeTuple::make_range(method()->signature());
577 init_tf(TypeFunc::make(domain, range));
578 StartNode* s = new (this, 2) StartOSRNode(root(), domain);
579 initial_gvn()->set_type_bottom(s);
580 init_start(s);
581 cg = CallGenerator::for_osr(method(), entry_bci());
582 } else {
583 // Normal case.
584 init_tf(TypeFunc::make(method()));
585 StartNode* s = new (this, 2) StartNode(root(), tf()->domain());
586 initial_gvn()->set_type_bottom(s);
587 init_start(s);
588 float past_uses = method()->interpreter_invocation_count();
589 float expected_uses = past_uses;
590 cg = CallGenerator::for_inline(method(), expected_uses);
591 }
592 if (failing()) return;
593 if (cg == NULL) {
594 record_method_not_compilable_all_tiers("cannot parse method");
595 return;
596 }
597 JVMState* jvms = build_start_state(start(), tf());
598 if ((jvms = cg->generate(jvms)) == NULL) {
599 record_method_not_compilable("method parse failed");
600 return;
601 }
602 GraphKit kit(jvms);
603
604 if (!kit.stopped()) {
605 // Accept return values, and transfer control we know not where.
606 // This is done by a special, unique ReturnNode bound to root.
607 return_values(kit.jvms());
608 }
609
610 if (kit.has_exceptions()) {
611 // Any exceptions that escape from this call must be rethrown
612 // to whatever caller is dynamically above us on the stack.
613 // This is done by a special, unique RethrowNode bound to root.
614 rethrow_exceptions(kit.transfer_exceptions_into_jvms());
615 }
616
617 if (!failing() && has_stringbuilder()) {
618 {
619 // remove useless nodes to make the usage analysis simpler
620 ResourceMark rm;
621 PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
622 }
623
624 {
625 ResourceMark rm;
626 print_method("Before StringOpts", 3);
627 PhaseStringOpts pso(initial_gvn(), &for_igvn);
628 print_method("After StringOpts", 3);
629 }
630
631 // now inline anything that we skipped the first time around
632 while (_late_inlines.length() > 0) {
633 CallGenerator* cg = _late_inlines.pop();
634 cg->do_late_inline();
635 }
636 }
637 assert(_late_inlines.length() == 0, "should have been processed");
638
639 print_method("Before RemoveUseless", 3);
640
641 // Remove clutter produced by parsing.
642 if (!failing()) {
643 ResourceMark rm;
644 PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
645 }
646 }
647
648 // Note: Large methods are capped off in do_one_bytecode().
649 if (failing()) return;
650
651 // After parsing, node notes are no longer automagic.
652 // They must be propagated by register_new_node_with_optimizer(),
653 // clone(), or the like.
654 set_default_node_notes(NULL);
655
656 for (;;) {
657 int successes = Inline_Warm();
658 if (failing()) return;
659 if (successes == 0) break;
660 }
661
662 // Drain the list.
663 Finish_Warm();
664 #ifndef PRODUCT
665 if (_printer) {
666 _printer->print_inlining(this);
667 }
668 #endif
669
670 if (failing()) return;
671 NOT_PRODUCT( verify_graph_edges(); )
672
673 // Now optimize
674 Optimize();
675 if (failing()) return;
676 NOT_PRODUCT( verify_graph_edges(); )
677
678 #ifndef PRODUCT
679 if (PrintIdeal) {
680 ttyLocker ttyl; // keep the following output all in one block
681 // This output goes directly to the tty, not the compiler log.
682 // To enable tools to match it up with the compilation activity,
683 // be sure to tag this tty output with the compile ID.
684 if (xtty != NULL) {
685 xtty->head("ideal compile_id='%d'%s", compile_id(),
686 is_osr_compilation() ? " compile_kind='osr'" :
687 "");
688 }
689 root()->dump(9999);
690 if (xtty != NULL) {
691 xtty->tail("ideal");
692 }
693 }
694 #endif
695
696 // Now that we know the size of all the monitors we can add a fixed slot
697 // for the original deopt pc.
698
699 _orig_pc_slot = fixed_slots();
700 int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
701 set_fixed_slots(next_slot);
702
703 // Now generate code
704 Code_Gen();
705 if (failing()) return;
706
707 // Check if we want to skip execution of all compiled code.
708 {
709 #ifndef PRODUCT
710 if (OptoNoExecute) {
711 record_method_not_compilable("+OptoNoExecute"); // Flag as failed
712 return;
713 }
714 TracePhase t2("install_code", &_t_registerMethod, TimeCompiler);
715 #endif
716
717 if (is_osr_compilation()) {
718 _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
719 _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
720 } else {
721 _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
722 _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
723 }
724
725 env()->register_method(_method, _entry_bci,
726 &_code_offsets,
727 _orig_pc_slot_offset_in_bytes,
728 code_buffer(),
729 frame_size_in_words(), _oop_map_set,
730 &_handler_table, &_inc_table,
731 compiler,
732 env()->comp_level(),
733 true, /*has_debug_info*/
734 has_unsafe_access()
735 );
736 }
737 }
738
739 //------------------------------Compile----------------------------------------
740 // Compile a runtime stub
741 Compile::Compile( ciEnv* ci_env,
742 TypeFunc_generator generator,
743 address stub_function,
744 const char *stub_name,
745 int is_fancy_jump,
746 bool pass_tls,
747 bool save_arg_registers,
748 bool return_pc )
749 : Phase(Compiler),
750 _env(ci_env),
751 _log(ci_env->log()),
752 _compile_id(-1),
753 _save_argument_registers(save_arg_registers),
754 _method(NULL),
755 _stub_name(stub_name),
756 _stub_function(stub_function),
757 _stub_entry_point(NULL),
758 _entry_bci(InvocationEntryBci),
759 _initial_gvn(NULL),
760 _for_igvn(NULL),
761 _warm_calls(NULL),
762 _orig_pc_slot(0),
763 _orig_pc_slot_offset_in_bytes(0),
764 _subsume_loads(true),
765 _do_escape_analysis(false),
766 _failure_reason(NULL),
767 _code_buffer("Compile::Fill_buffer"),
768 _has_method_handle_invokes(false),
769 _mach_constant_base_node(NULL),
770 _node_bundling_limit(0),
771 _node_bundling_base(NULL),
772 _java_calls(0),
773 _inner_loops(0),
774 #ifndef PRODUCT
775 _trace_opto_output(TraceOptoOutput),
776 _printer(NULL),
777 #endif
778 _congraph(NULL) {
779 C = this;
780
781 #ifndef PRODUCT
782 TraceTime t1(NULL, &_t_totalCompilation, TimeCompiler, false);
783 TraceTime t2(NULL, &_t_stubCompilation, TimeCompiler, false);
784 set_print_assembly(PrintFrameConverterAssembly);
785 set_parsed_irreducible_loop(false);
786 #endif
787 CompileWrapper cw(this);
788 Init(/*AliasLevel=*/ 0);
789 init_tf((*generator)());
790
791 {
792 // The following is a dummy for the sake of GraphKit::gen_stub
793 Unique_Node_List for_igvn(comp_arena());
794 set_for_igvn(&for_igvn); // not used, but some GraphKit guys push on this
795 PhaseGVN gvn(Thread::current()->resource_area(),255);
796 set_initial_gvn(&gvn); // not significant, but GraphKit guys use it pervasively
797 gvn.transform_no_reclaim(top());
798
799 GraphKit kit;
800 kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
801 }
802
803 NOT_PRODUCT( verify_graph_edges(); )
804 Code_Gen();
805 if (failing()) return;
806
807
808 // Entry point will be accessed using compile->stub_entry_point();
809 if (code_buffer() == NULL) {
810 Matcher::soft_match_failure();
811 } else {
812 if (PrintAssembly && (WizardMode || Verbose))
813 tty->print_cr("### Stub::%s", stub_name);
814
815 if (!failing()) {
816 assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
817
818 // Make the NMethod
819 // For now we mark the frame as never safe for profile stackwalking
820 RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
821 code_buffer(),
822 CodeOffsets::frame_never_safe,
823 // _code_offsets.value(CodeOffsets::Frame_Complete),
824 frame_size_in_words(),
825 _oop_map_set,
826 save_arg_registers);
827 assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
828
829 _stub_entry_point = rs->entry_point();
830 }
831 }
832 }
833
834 #ifndef PRODUCT
835 void print_opto_verbose_signature( const TypeFunc *j_sig, const char *stub_name ) {
836 if(PrintOpto && Verbose) {
837 tty->print("%s ", stub_name); j_sig->print_flattened(); tty->cr();
838 }
839 }
840 #endif
841
842 void Compile::print_codes() {
843 }
844
845 //------------------------------Init-------------------------------------------
846 // Prepare for a single compilation
847 void Compile::Init(int aliaslevel) {
848 _unique = 0;
849 _regalloc = NULL;
850
851 _tf = NULL; // filled in later
852 _top = NULL; // cached later
853 _matcher = NULL; // filled in later
854 _cfg = NULL; // filled in later
855
856 set_24_bit_selection_and_mode(Use24BitFP, false);
857
858 _node_note_array = NULL;
859 _default_node_notes = NULL;
860
861 _immutable_memory = NULL; // filled in at first inquiry
862
863 // Globally visible Nodes
864 // First set TOP to NULL to give safe behavior during creation of RootNode
865 set_cached_top_node(NULL);
866 set_root(new (this, 3) RootNode());
867 // Now that you have a Root to point to, create the real TOP
868 set_cached_top_node( new (this, 1) ConNode(Type::TOP) );
869 set_recent_alloc(NULL, NULL);
870
871 // Create Debug Information Recorder to record scopes, oopmaps, etc.
872 env()->set_oop_recorder(new OopRecorder(comp_arena()));
873 env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
874 env()->set_dependencies(new Dependencies(env()));
875
876 _fixed_slots = 0;
877 set_has_split_ifs(false);
878 set_has_loops(has_method() && method()->has_loops()); // first approximation
879 set_has_stringbuilder(false);
880 _trap_can_recompile = false; // no traps emitted yet
881 _major_progress = true; // start out assuming good things will happen
882 set_has_unsafe_access(false);
883 Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
884 set_decompile_count(0);
885
886 set_do_freq_based_layout(BlockLayoutByFrequency || method_has_option("BlockLayoutByFrequency"));
887 set_num_loop_opts(LoopOptsCount);
888 set_do_inlining(Inline);
889 set_max_inline_size(MaxInlineSize);
890 set_freq_inline_size(FreqInlineSize);
891 set_do_scheduling(OptoScheduling);
892 set_do_count_invocations(false);
893 set_do_method_data_update(false);
894
895 if (debug_info()->recording_non_safepoints()) {
896 set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
897 (comp_arena(), 8, 0, NULL));
898 set_default_node_notes(Node_Notes::make(this));
899 }
900
901 // // -- Initialize types before each compile --
902 // // Update cached type information
903 // if( _method && _method->constants() )
904 // Type::update_loaded_types(_method, _method->constants());
905
906 // Init alias_type map.
907 if (!_do_escape_analysis && aliaslevel == 3)
908 aliaslevel = 2; // No unique types without escape analysis
909 _AliasLevel = aliaslevel;
910 const int grow_ats = 16;
911 _max_alias_types = grow_ats;
912 _alias_types = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
913 AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType, grow_ats);
914 Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
915 {
916 for (int i = 0; i < grow_ats; i++) _alias_types[i] = &ats[i];
917 }
918 // Initialize the first few types.
919 _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
920 _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
921 _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
922 _num_alias_types = AliasIdxRaw+1;
923 // Zero out the alias type cache.
924 Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
925 // A NULL adr_type hits in the cache right away. Preload the right answer.
926 probe_alias_cache(NULL)->_index = AliasIdxTop;
927
928 _intrinsics = NULL;
929 _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
930 _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
931 register_library_intrinsics();
932 }
933
934 //---------------------------init_start----------------------------------------
935 // Install the StartNode on this compile object.
936 void Compile::init_start(StartNode* s) {
937 if (failing())
938 return; // already failing
939 assert(s == start(), "");
940 }
941
942 StartNode* Compile::start() const {
943 assert(!failing(), "");
944 for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
945 Node* start = root()->fast_out(i);
946 if( start->is_Start() )
947 return start->as_Start();
948 }
949 ShouldNotReachHere();
950 return NULL;
951 }
952
953 //-------------------------------immutable_memory-------------------------------------
954 // Access immutable memory
955 Node* Compile::immutable_memory() {
956 if (_immutable_memory != NULL) {
957 return _immutable_memory;
958 }
959 StartNode* s = start();
960 for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
961 Node *p = s->fast_out(i);
962 if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
963 _immutable_memory = p;
964 return _immutable_memory;
965 }
966 }
967 ShouldNotReachHere();
968 return NULL;
969 }
970
971 //----------------------set_cached_top_node------------------------------------
972 // Install the cached top node, and make sure Node::is_top works correctly.
973 void Compile::set_cached_top_node(Node* tn) {
974 if (tn != NULL) verify_top(tn);
975 Node* old_top = _top;
976 _top = tn;
977 // Calling Node::setup_is_top allows the nodes the chance to adjust
978 // their _out arrays.
979 if (_top != NULL) _top->setup_is_top();
980 if (old_top != NULL) old_top->setup_is_top();
981 assert(_top == NULL || top()->is_top(), "");
982 }
983
984 #ifndef PRODUCT
985 void Compile::verify_top(Node* tn) const {
986 if (tn != NULL) {
987 assert(tn->is_Con(), "top node must be a constant");
988 assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
989 assert(tn->in(0) != NULL, "must have live top node");
990 }
991 }
992 #endif
993
994
995 ///-------------------Managing Per-Node Debug & Profile Info-------------------
996
997 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
998 guarantee(arr != NULL, "");
999 int num_blocks = arr->length();
1000 if (grow_by < num_blocks) grow_by = num_blocks;
1001 int num_notes = grow_by * _node_notes_block_size;
1002 Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1003 Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1004 while (num_notes > 0) {
1005 arr->append(notes);
1006 notes += _node_notes_block_size;
1007 num_notes -= _node_notes_block_size;
1008 }
1009 assert(num_notes == 0, "exact multiple, please");
1010 }
1011
1012 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1013 if (source == NULL || dest == NULL) return false;
1014
1015 if (dest->is_Con())
1016 return false; // Do not push debug info onto constants.
1017
1018 #ifdef ASSERT
1019 // Leave a bread crumb trail pointing to the original node:
1020 if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
1021 dest->set_debug_orig(source);
1022 }
1023 #endif
1024
1025 if (node_note_array() == NULL)
1026 return false; // Not collecting any notes now.
1027
1028 // This is a copy onto a pre-existing node, which may already have notes.
1029 // If both nodes have notes, do not overwrite any pre-existing notes.
1030 Node_Notes* source_notes = node_notes_at(source->_idx);
1031 if (source_notes == NULL || source_notes->is_clear()) return false;
1032 Node_Notes* dest_notes = node_notes_at(dest->_idx);
1033 if (dest_notes == NULL || dest_notes->is_clear()) {
1034 return set_node_notes_at(dest->_idx, source_notes);
1035 }
1036
1037 Node_Notes merged_notes = (*source_notes);
1038 // The order of operations here ensures that dest notes will win...
1039 merged_notes.update_from(dest_notes);
1040 return set_node_notes_at(dest->_idx, &merged_notes);
1041 }
1042
1043
1044 //--------------------------allow_range_check_smearing-------------------------
1045 // Gating condition for coalescing similar range checks.
1046 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1047 // single covering check that is at least as strong as any of them.
1048 // If the optimization succeeds, the simplified (strengthened) range check
1049 // will always succeed. If it fails, we will deopt, and then give up
1050 // on the optimization.
1051 bool Compile::allow_range_check_smearing() const {
1052 // If this method has already thrown a range-check,
1053 // assume it was because we already tried range smearing
1054 // and it failed.
1055 uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1056 return !already_trapped;
1057 }
1058
1059
1060 //------------------------------flatten_alias_type-----------------------------
1061 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1062 int offset = tj->offset();
1063 TypePtr::PTR ptr = tj->ptr();
1064
1065 // Known instance (scalarizable allocation) alias only with itself.
1066 bool is_known_inst = tj->isa_oopptr() != NULL &&
1067 tj->is_oopptr()->is_known_instance();
1068
1069 // Process weird unsafe references.
1070 if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1071 assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
1072 assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1073 tj = TypeOopPtr::BOTTOM;
1074 ptr = tj->ptr();
1075 offset = tj->offset();
1076 }
1077
1078 // Array pointers need some flattening
1079 const TypeAryPtr *ta = tj->isa_aryptr();
1080 if( ta && is_known_inst ) {
1081 if ( offset != Type::OffsetBot &&
1082 offset > arrayOopDesc::length_offset_in_bytes() ) {
1083 offset = Type::OffsetBot; // Flatten constant access into array body only
1084 tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
1085 }
1086 } else if( ta && _AliasLevel >= 2 ) {
1087 // For arrays indexed by constant indices, we flatten the alias
1088 // space to include all of the array body. Only the header, klass
1089 // and array length can be accessed un-aliased.
1090 if( offset != Type::OffsetBot ) {
1091 if( ta->const_oop() ) { // methodDataOop or methodOop
1092 offset = Type::OffsetBot; // Flatten constant access into array body
1093 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
1094 } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1095 // range is OK as-is.
1096 tj = ta = TypeAryPtr::RANGE;
1097 } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1098 tj = TypeInstPtr::KLASS; // all klass loads look alike
1099 ta = TypeAryPtr::RANGE; // generic ignored junk
1100 ptr = TypePtr::BotPTR;
1101 } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1102 tj = TypeInstPtr::MARK;
1103 ta = TypeAryPtr::RANGE; // generic ignored junk
1104 ptr = TypePtr::BotPTR;
1105 } else { // Random constant offset into array body
1106 offset = Type::OffsetBot; // Flatten constant access into array body
1107 tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
1108 }
1109 }
1110 // Arrays of fixed size alias with arrays of unknown size.
1111 if (ta->size() != TypeInt::POS) {
1112 const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1113 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
1114 }
1115 // Arrays of known objects become arrays of unknown objects.
1116 if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1117 const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1118 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1119 }
1120 if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1121 const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1122 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1123 }
1124 // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1125 // cannot be distinguished by bytecode alone.
1126 if (ta->elem() == TypeInt::BOOL) {
1127 const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1128 ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1129 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
1130 }
1131 // During the 2nd round of IterGVN, NotNull castings are removed.
1132 // Make sure the Bottom and NotNull variants alias the same.
1133 // Also, make sure exact and non-exact variants alias the same.
1134 if( ptr == TypePtr::NotNull || ta->klass_is_exact() ) {
1135 if (ta->const_oop()) {
1136 tj = ta = TypeAryPtr::make(TypePtr::Constant,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
1137 } else {
1138 tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
1139 }
1140 }
1141 }
1142
1143 // Oop pointers need some flattening
1144 const TypeInstPtr *to = tj->isa_instptr();
1145 if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
1146 if( ptr == TypePtr::Constant ) {
1147 // No constant oop pointers (such as Strings); they alias with
1148 // unknown strings.
1149 assert(!is_known_inst, "not scalarizable allocation");
1150 tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1151 } else if( is_known_inst ) {
1152 tj = to; // Keep NotNull and klass_is_exact for instance type
1153 } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1154 // During the 2nd round of IterGVN, NotNull castings are removed.
1155 // Make sure the Bottom and NotNull variants alias the same.
1156 // Also, make sure exact and non-exact variants alias the same.
1157 tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1158 }
1159 // Canonicalize the holder of this field
1160 ciInstanceKlass *k = to->klass()->as_instance_klass();
1161 if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1162 // First handle header references such as a LoadKlassNode, even if the
1163 // object's klass is unloaded at compile time (4965979).
1164 if (!is_known_inst) { // Do it only for non-instance types
1165 tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
1166 }
1167 } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
1168 to = NULL;
1169 tj = TypeOopPtr::BOTTOM;
1170 offset = tj->offset();
1171 } else {
1172 ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
1173 if (!k->equals(canonical_holder) || tj->offset() != offset) {
1174 if( is_known_inst ) {
1175 tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
1176 } else {
1177 tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
1178 }
1179 }
1180 }
1181 }
1182
1183 // Klass pointers to object array klasses need some flattening
1184 const TypeKlassPtr *tk = tj->isa_klassptr();
1185 if( tk ) {
1186 // If we are referencing a field within a Klass, we need
1187 // to assume the worst case of an Object. Both exact and
1188 // inexact types must flatten to the same alias class.
1189 // Since the flattened result for a klass is defined to be
1190 // precisely java.lang.Object, use a constant ptr.
1191 if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1192
1193 tj = tk = TypeKlassPtr::make(TypePtr::Constant,
1194 TypeKlassPtr::OBJECT->klass(),
1195 offset);
1196 }
1197
1198 ciKlass* klass = tk->klass();
1199 if( klass->is_obj_array_klass() ) {
1200 ciKlass* k = TypeAryPtr::OOPS->klass();
1201 if( !k || !k->is_loaded() ) // Only fails for some -Xcomp runs
1202 k = TypeInstPtr::BOTTOM->klass();
1203 tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
1204 }
1205
1206 // Check for precise loads from the primary supertype array and force them
1207 // to the supertype cache alias index. Check for generic array loads from
1208 // the primary supertype array and also force them to the supertype cache
1209 // alias index. Since the same load can reach both, we need to merge
1210 // these 2 disparate memories into the same alias class. Since the
1211 // primary supertype array is read-only, there's no chance of confusion
1212 // where we bypass an array load and an array store.
1213 uint off2 = offset - Klass::primary_supers_offset_in_bytes();
1214 if( offset == Type::OffsetBot ||
1215 off2 < Klass::primary_super_limit()*wordSize ) {
1216 offset = sizeof(oopDesc) +Klass::secondary_super_cache_offset_in_bytes();
1217 tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
1218 }
1219 }
1220
1221 // Flatten all Raw pointers together.
1222 if (tj->base() == Type::RawPtr)
1223 tj = TypeRawPtr::BOTTOM;
1224
1225 if (tj->base() == Type::AnyPtr)
1226 tj = TypePtr::BOTTOM; // An error, which the caller must check for.
1227
1228 // Flatten all to bottom for now
1229 switch( _AliasLevel ) {
1230 case 0:
1231 tj = TypePtr::BOTTOM;
1232 break;
1233 case 1: // Flatten to: oop, static, field or array
1234 switch (tj->base()) {
1235 //case Type::AryPtr: tj = TypeAryPtr::RANGE; break;
1236 case Type::RawPtr: tj = TypeRawPtr::BOTTOM; break;
1237 case Type::AryPtr: // do not distinguish arrays at all
1238 case Type::InstPtr: tj = TypeInstPtr::BOTTOM; break;
1239 case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
1240 case Type::AnyPtr: tj = TypePtr::BOTTOM; break; // caller checks it
1241 default: ShouldNotReachHere();
1242 }
1243 break;
1244 case 2: // No collapsing at level 2; keep all splits
1245 case 3: // No collapsing at level 3; keep all splits
1246 break;
1247 default:
1248 Unimplemented();
1249 }
1250
1251 offset = tj->offset();
1252 assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1253
1254 assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1255 (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1256 (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1257 (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1258 (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1259 (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1260 (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr) ,
1261 "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1262 assert( tj->ptr() != TypePtr::TopPTR &&
1263 tj->ptr() != TypePtr::AnyNull &&
1264 tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1265 // assert( tj->ptr() != TypePtr::Constant ||
1266 // tj->base() == Type::RawPtr ||
1267 // tj->base() == Type::KlassPtr, "No constant oop addresses" );
1268
1269 return tj;
1270 }
1271
1272 void Compile::AliasType::Init(int i, const TypePtr* at) {
1273 _index = i;
1274 _adr_type = at;
1275 _field = NULL;
1276 _is_rewritable = true; // default
1277 const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
1278 if (atoop != NULL && atoop->is_known_instance()) {
1279 const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1280 _general_index = Compile::current()->get_alias_index(gt);
1281 } else {
1282 _general_index = 0;
1283 }
1284 }
1285
1286 //---------------------------------print_on------------------------------------
1287 #ifndef PRODUCT
1288 void Compile::AliasType::print_on(outputStream* st) {
1289 if (index() < 10)
1290 st->print("@ <%d> ", index());
1291 else st->print("@ <%d>", index());
1292 st->print(is_rewritable() ? " " : " RO");
1293 int offset = adr_type()->offset();
1294 if (offset == Type::OffsetBot)
1295 st->print(" +any");
1296 else st->print(" +%-3d", offset);
1297 st->print(" in ");
1298 adr_type()->dump_on(st);
1299 const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1300 if (field() != NULL && tjp) {
1301 if (tjp->klass() != field()->holder() ||
1302 tjp->offset() != field()->offset_in_bytes()) {
1303 st->print(" != ");
1304 field()->print();
1305 st->print(" ***");
1306 }
1307 }
1308 }
1309
1310 void print_alias_types() {
1311 Compile* C = Compile::current();
1312 tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1313 for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1314 C->alias_type(idx)->print_on(tty);
1315 tty->cr();
1316 }
1317 }
1318 #endif
1319
1320
1321 //----------------------------probe_alias_cache--------------------------------
1322 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1323 intptr_t key = (intptr_t) adr_type;
1324 key ^= key >> logAliasCacheSize;
1325 return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1326 }
1327
1328
1329 //-----------------------------grow_alias_types--------------------------------
1330 void Compile::grow_alias_types() {
1331 const int old_ats = _max_alias_types; // how many before?
1332 const int new_ats = old_ats; // how many more?
1333 const int grow_ats = old_ats+new_ats; // how many now?
1334 _max_alias_types = grow_ats;
1335 _alias_types = REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1336 AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1337 Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1338 for (int i = 0; i < new_ats; i++) _alias_types[old_ats+i] = &ats[i];
1339 }
1340
1341
1342 //--------------------------------find_alias_type------------------------------
1343 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create) {
1344 if (_AliasLevel == 0)
1345 return alias_type(AliasIdxBot);
1346
1347 AliasCacheEntry* ace = probe_alias_cache(adr_type);
1348 if (ace->_adr_type == adr_type) {
1349 return alias_type(ace->_index);
1350 }
1351
1352 // Handle special cases.
1353 if (adr_type == NULL) return alias_type(AliasIdxTop);
1354 if (adr_type == TypePtr::BOTTOM) return alias_type(AliasIdxBot);
1355
1356 // Do it the slow way.
1357 const TypePtr* flat = flatten_alias_type(adr_type);
1358
1359 #ifdef ASSERT
1360 assert(flat == flatten_alias_type(flat), "idempotent");
1361 assert(flat != TypePtr::BOTTOM, "cannot alias-analyze an untyped ptr");
1362 if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1363 const TypeOopPtr* foop = flat->is_oopptr();
1364 // Scalarizable allocations have exact klass always.
1365 bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1366 const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1367 assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type");
1368 }
1369 assert(flat == flatten_alias_type(flat), "exact bit doesn't matter");
1370 #endif
1371
1372 int idx = AliasIdxTop;
1373 for (int i = 0; i < num_alias_types(); i++) {
1374 if (alias_type(i)->adr_type() == flat) {
1375 idx = i;
1376 break;
1377 }
1378 }
1379
1380 if (idx == AliasIdxTop) {
1381 if (no_create) return NULL;
1382 // Grow the array if necessary.
1383 if (_num_alias_types == _max_alias_types) grow_alias_types();
1384 // Add a new alias type.
1385 idx = _num_alias_types++;
1386 _alias_types[idx]->Init(idx, flat);
1387 if (flat == TypeInstPtr::KLASS) alias_type(idx)->set_rewritable(false);
1388 if (flat == TypeAryPtr::RANGE) alias_type(idx)->set_rewritable(false);
1389 if (flat->isa_instptr()) {
1390 if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
1391 && flat->is_instptr()->klass() == env()->Class_klass())
1392 alias_type(idx)->set_rewritable(false);
1393 }
1394 if (flat->isa_klassptr()) {
1395 if (flat->offset() == Klass::super_check_offset_offset_in_bytes() + (int)sizeof(oopDesc))
1396 alias_type(idx)->set_rewritable(false);
1397 if (flat->offset() == Klass::modifier_flags_offset_in_bytes() + (int)sizeof(oopDesc))
1398 alias_type(idx)->set_rewritable(false);
1399 if (flat->offset() == Klass::access_flags_offset_in_bytes() + (int)sizeof(oopDesc))
1400 alias_type(idx)->set_rewritable(false);
1401 if (flat->offset() == Klass::java_mirror_offset_in_bytes() + (int)sizeof(oopDesc))
1402 alias_type(idx)->set_rewritable(false);
1403 }
1404 // %%% (We would like to finalize JavaThread::threadObj_offset(),
1405 // but the base pointer type is not distinctive enough to identify
1406 // references into JavaThread.)
1407
1408 // Check for final instance fields.
1409 const TypeInstPtr* tinst = flat->isa_instptr();
1410 if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1411 ciInstanceKlass *k = tinst->klass()->as_instance_klass();
1412 ciField* field = k->get_field_by_offset(tinst->offset(), false);
1413 // Set field() and is_rewritable() attributes.
1414 if (field != NULL) alias_type(idx)->set_field(field);
1415 }
1416 const TypeKlassPtr* tklass = flat->isa_klassptr();
1417 // Check for final static fields.
1418 if (tklass && tklass->klass()->is_instance_klass()) {
1419 ciInstanceKlass *k = tklass->klass()->as_instance_klass();
1420 ciField* field = k->get_field_by_offset(tklass->offset(), true);
1421 // Set field() and is_rewritable() attributes.
1422 if (field != NULL) alias_type(idx)->set_field(field);
1423 }
1424 }
1425
1426 // Fill the cache for next time.
1427 ace->_adr_type = adr_type;
1428 ace->_index = idx;
1429 assert(alias_type(adr_type) == alias_type(idx), "type must be installed");
1430
1431 // Might as well try to fill the cache for the flattened version, too.
1432 AliasCacheEntry* face = probe_alias_cache(flat);
1433 if (face->_adr_type == NULL) {
1434 face->_adr_type = flat;
1435 face->_index = idx;
1436 assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1437 }
1438
1439 return alias_type(idx);
1440 }
1441
1442
1443 Compile::AliasType* Compile::alias_type(ciField* field) {
1444 const TypeOopPtr* t;
1445 if (field->is_static())
1446 t = TypeKlassPtr::make(field->holder());
1447 else
1448 t = TypeOopPtr::make_from_klass_raw(field->holder());
1449 AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()));
1450 assert(field->is_final() == !atp->is_rewritable(), "must get the rewritable bits correct");
1451 return atp;
1452 }
1453
1454
1455 //------------------------------have_alias_type--------------------------------
1456 bool Compile::have_alias_type(const TypePtr* adr_type) {
1457 AliasCacheEntry* ace = probe_alias_cache(adr_type);
1458 if (ace->_adr_type == adr_type) {
1459 return true;
1460 }
1461
1462 // Handle special cases.
1463 if (adr_type == NULL) return true;
1464 if (adr_type == TypePtr::BOTTOM) return true;
1465
1466 return find_alias_type(adr_type, true) != NULL;
1467 }
1468
1469 //-----------------------------must_alias--------------------------------------
1470 // True if all values of the given address type are in the given alias category.
1471 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1472 if (alias_idx == AliasIdxBot) return true; // the universal category
1473 if (adr_type == NULL) return true; // NULL serves as TypePtr::TOP
1474 if (alias_idx == AliasIdxTop) return false; // the empty category
1475 if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1476
1477 // the only remaining possible overlap is identity
1478 int adr_idx = get_alias_index(adr_type);
1479 assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1480 assert(adr_idx == alias_idx ||
1481 (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1482 && adr_type != TypeOopPtr::BOTTOM),
1483 "should not be testing for overlap with an unsafe pointer");
1484 return adr_idx == alias_idx;
1485 }
1486
1487 //------------------------------can_alias--------------------------------------
1488 // True if any values of the given address type are in the given alias category.
1489 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1490 if (alias_idx == AliasIdxTop) return false; // the empty category
1491 if (adr_type == NULL) return false; // NULL serves as TypePtr::TOP
1492 if (alias_idx == AliasIdxBot) return true; // the universal category
1493 if (adr_type->base() == Type::AnyPtr) return true; // TypePtr::BOTTOM or its twins
1494
1495 // the only remaining possible overlap is identity
1496 int adr_idx = get_alias_index(adr_type);
1497 assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1498 return adr_idx == alias_idx;
1499 }
1500
1501
1502
1503 //---------------------------pop_warm_call-------------------------------------
1504 WarmCallInfo* Compile::pop_warm_call() {
1505 WarmCallInfo* wci = _warm_calls;
1506 if (wci != NULL) _warm_calls = wci->remove_from(wci);
1507 return wci;
1508 }
1509
1510 //----------------------------Inline_Warm--------------------------------------
1511 int Compile::Inline_Warm() {
1512 // If there is room, try to inline some more warm call sites.
1513 // %%% Do a graph index compaction pass when we think we're out of space?
1514 if (!InlineWarmCalls) return 0;
1515
1516 int calls_made_hot = 0;
1517 int room_to_grow = NodeCountInliningCutoff - unique();
1518 int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
1519 int amount_grown = 0;
1520 WarmCallInfo* call;
1521 while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
1522 int est_size = (int)call->size();
1523 if (est_size > (room_to_grow - amount_grown)) {
1524 // This one won't fit anyway. Get rid of it.
1525 call->make_cold();
1526 continue;
1527 }
1528 call->make_hot();
1529 calls_made_hot++;
1530 amount_grown += est_size;
1531 amount_to_grow -= est_size;
1532 }
1533
1534 if (calls_made_hot > 0) set_major_progress();
1535 return calls_made_hot;
1536 }
1537
1538
1539 //----------------------------Finish_Warm--------------------------------------
1540 void Compile::Finish_Warm() {
1541 if (!InlineWarmCalls) return;
1542 if (failing()) return;
1543 if (warm_calls() == NULL) return;
1544
1545 // Clean up loose ends, if we are out of space for inlining.
1546 WarmCallInfo* call;
1547 while ((call = pop_warm_call()) != NULL) {
1548 call->make_cold();
1549 }
1550 }
1551
1552 //---------------------cleanup_loop_predicates-----------------------
1553 // Remove the opaque nodes that protect the predicates so that all unused
1554 // checks and uncommon_traps will be eliminated from the ideal graph
1555 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
1556 if (predicate_count()==0) return;
1557 for (int i = predicate_count(); i > 0; i--) {
1558 Node * n = predicate_opaque1_node(i-1);
1559 assert(n->Opcode() == Op_Opaque1, "must be");
1560 igvn.replace_node(n, n->in(1));
1561 }
1562 assert(predicate_count()==0, "should be clean!");
1563 igvn.optimize();
1564 }
1565
1566 //------------------------------Optimize---------------------------------------
1567 // Given a graph, optimize it.
1568 void Compile::Optimize() {
1569 TracePhase t1("optimizer", &_t_optimizer, true);
1570
1571 #ifndef PRODUCT
1572 if (env()->break_at_compile()) {
1573 BREAKPOINT;
1574 }
1575
1576 #endif
1577
1578 ResourceMark rm;
1579 int loop_opts_cnt;
1580
1581 NOT_PRODUCT( verify_graph_edges(); )
1582
1583 print_method("After Parsing");
1584
1585 {
1586 // Iterative Global Value Numbering, including ideal transforms
1587 // Initialize IterGVN with types and values from parse-time GVN
1588 PhaseIterGVN igvn(initial_gvn());
1589 {
1590 NOT_PRODUCT( TracePhase t2("iterGVN", &_t_iterGVN, TimeCompiler); )
1591 igvn.optimize();
1592 }
1593
1594 print_method("Iter GVN 1", 2);
1595
1596 if (failing()) return;
1597
1598 // Perform escape analysis
1599 if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
1600 TracePhase t2("escapeAnalysis", &_t_escapeAnalysis, true);
1601 ConnectionGraph::do_analysis(this, &igvn);
1602
1603 if (failing()) return;
1604
1605 igvn.optimize();
1606 print_method("Iter GVN 3", 2);
1607
1608 if (failing()) return;
1609
1610 }
1611
1612 // Loop transforms on the ideal graph. Range Check Elimination,
1613 // peeling, unrolling, etc.
1614
1615 // Set loop opts counter
1616 loop_opts_cnt = num_loop_opts();
1617 if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
1618 {
1619 TracePhase t2("idealLoop", &_t_idealLoop, true);
1620 PhaseIdealLoop ideal_loop( igvn, true, UseLoopPredicate);
1621 loop_opts_cnt--;
1622 if (major_progress()) print_method("PhaseIdealLoop 1", 2);
1623 if (failing()) return;
1624 }
1625 // Loop opts pass if partial peeling occurred in previous pass
1626 if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
1627 TracePhase t3("idealLoop", &_t_idealLoop, true);
1628 PhaseIdealLoop ideal_loop( igvn, false, UseLoopPredicate);
1629 loop_opts_cnt--;
1630 if (major_progress()) print_method("PhaseIdealLoop 2", 2);
1631 if (failing()) return;
1632 }
1633 // Loop opts pass for loop-unrolling before CCP
1634 if(major_progress() && (loop_opts_cnt > 0)) {
1635 TracePhase t4("idealLoop", &_t_idealLoop, true);
1636 PhaseIdealLoop ideal_loop( igvn, false, UseLoopPredicate);
1637 loop_opts_cnt--;
1638 if (major_progress()) print_method("PhaseIdealLoop 3", 2);
1639 }
1640 if (!failing()) {
1641 // Verify that last round of loop opts produced a valid graph
1642 NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
1643 PhaseIdealLoop::verify(igvn);
1644 }
1645 }
1646 if (failing()) return;
1647
1648 // Conditional Constant Propagation;
1649 PhaseCCP ccp( &igvn );
1650 assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
1651 {
1652 TracePhase t2("ccp", &_t_ccp, true);
1653 ccp.do_transform();
1654 }
1655 print_method("PhaseCPP 1", 2);
1656
1657 assert( true, "Break here to ccp.dump_old2new_map()");
1658
1659 // Iterative Global Value Numbering, including ideal transforms
1660 {
1661 NOT_PRODUCT( TracePhase t2("iterGVN2", &_t_iterGVN2, TimeCompiler); )
1662 igvn = ccp;
1663 igvn.optimize();
1664 }
1665
1666 print_method("Iter GVN 2", 2);
1667
1668 if (failing()) return;
1669
1670 // Loop transforms on the ideal graph. Range Check Elimination,
1671 // peeling, unrolling, etc.
1672 if(loop_opts_cnt > 0) {
1673 debug_only( int cnt = 0; );
1674 bool loop_predication = UseLoopPredicate;
1675 while(major_progress() && (loop_opts_cnt > 0)) {
1676 TracePhase t2("idealLoop", &_t_idealLoop, true);
1677 assert( cnt++ < 40, "infinite cycle in loop optimization" );
1678 PhaseIdealLoop ideal_loop( igvn, true, loop_predication);
1679 loop_opts_cnt--;
1680 if (major_progress()) print_method("PhaseIdealLoop iterations", 2);
1681 if (failing()) return;
1682 // Perform loop predication optimization during first iteration after CCP.
1683 // After that switch it off and cleanup unused loop predicates.
1684 if (loop_predication) {
1685 loop_predication = false;
1686 cleanup_loop_predicates(igvn);
1687 if (failing()) return;
1688 }
1689 }
1690 }
1691
1692 {
1693 // Verify that all previous optimizations produced a valid graph
1694 // at least to this point, even if no loop optimizations were done.
1695 NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
1696 PhaseIdealLoop::verify(igvn);
1697 }
1698
1699 {
1700 NOT_PRODUCT( TracePhase t2("macroExpand", &_t_macroExpand, TimeCompiler); )
1701 PhaseMacroExpand mex(igvn);
1702 if (mex.expand_macro_nodes()) {
1703 assert(failing(), "must bail out w/ explicit message");
1704 return;
1705 }
1706 }
1707
1708 } // (End scope of igvn; run destructor if necessary for asserts.)
1709
1710 // A method with only infinite loops has no edges entering loops from root
1711 {
1712 NOT_PRODUCT( TracePhase t2("graphReshape", &_t_graphReshaping, TimeCompiler); )
1713 if (final_graph_reshaping()) {
1714 assert(failing(), "must bail out w/ explicit message");
1715 return;
1716 }
1717 }
1718
1719 print_method("Optimize finished", 2);
1720 }
1721
1722
1723 //------------------------------Code_Gen---------------------------------------
1724 // Given a graph, generate code for it
1725 void Compile::Code_Gen() {
1726 if (failing()) return;
1727
1728 // Perform instruction selection. You might think we could reclaim Matcher
1729 // memory PDQ, but actually the Matcher is used in generating spill code.
1730 // Internals of the Matcher (including some VectorSets) must remain live
1731 // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
1732 // set a bit in reclaimed memory.
1733
1734 // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
1735 // nodes. Mapping is only valid at the root of each matched subtree.
1736 NOT_PRODUCT( verify_graph_edges(); )
1737
1738 Node_List proj_list;
1739 Matcher m(proj_list);
1740 _matcher = &m;
1741 {
1742 TracePhase t2("matcher", &_t_matcher, true);
1743 m.match();
1744 }
1745 // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
1746 // nodes. Mapping is only valid at the root of each matched subtree.
1747 NOT_PRODUCT( verify_graph_edges(); )
1748
1749 // If you have too many nodes, or if matching has failed, bail out
1750 check_node_count(0, "out of nodes matching instructions");
1751 if (failing()) return;
1752
1753 // Build a proper-looking CFG
1754 PhaseCFG cfg(node_arena(), root(), m);
1755 _cfg = &cfg;
1756 {
1757 NOT_PRODUCT( TracePhase t2("scheduler", &_t_scheduler, TimeCompiler); )
1758 cfg.Dominators();
1759 if (failing()) return;
1760
1761 NOT_PRODUCT( verify_graph_edges(); )
1762
1763 cfg.Estimate_Block_Frequency();
1764 cfg.GlobalCodeMotion(m,unique(),proj_list);
1765
1766 print_method("Global code motion", 2);
1767
1768 if (failing()) return;
1769 NOT_PRODUCT( verify_graph_edges(); )
1770
1771 debug_only( cfg.verify(); )
1772 }
1773 NOT_PRODUCT( verify_graph_edges(); )
1774
1775 PhaseChaitin regalloc(unique(),cfg,m);
1776 _regalloc = ®alloc;
1777 {
1778 TracePhase t2("regalloc", &_t_registerAllocation, true);
1779 // Perform any platform dependent preallocation actions. This is used,
1780 // for example, to avoid taking an implicit null pointer exception
1781 // using the frame pointer on win95.
1782 _regalloc->pd_preallocate_hook();
1783
1784 // Perform register allocation. After Chaitin, use-def chains are
1785 // no longer accurate (at spill code) and so must be ignored.
1786 // Node->LRG->reg mappings are still accurate.
1787 _regalloc->Register_Allocate();
1788
1789 // Bail out if the allocator builds too many nodes
1790 if (failing()) return;
1791 }
1792
1793 // Prior to register allocation we kept empty basic blocks in case the
1794 // the allocator needed a place to spill. After register allocation we
1795 // are not adding any new instructions. If any basic block is empty, we
1796 // can now safely remove it.
1797 {
1798 NOT_PRODUCT( TracePhase t2("blockOrdering", &_t_blockOrdering, TimeCompiler); )
1799 cfg.remove_empty();
1800 if (do_freq_based_layout()) {
1801 PhaseBlockLayout layout(cfg);
1802 } else {
1803 cfg.set_loop_alignment();
1804 }
1805 cfg.fixup_flow();
1806 }
1807
1808 // Perform any platform dependent postallocation verifications.
1809 debug_only( _regalloc->pd_postallocate_verify_hook(); )
1810
1811 // Apply peephole optimizations
1812 if( OptoPeephole ) {
1813 NOT_PRODUCT( TracePhase t2("peephole", &_t_peephole, TimeCompiler); )
1814 PhasePeephole peep( _regalloc, cfg);
1815 peep.do_transform();
1816 }
1817
1818 // Convert Nodes to instruction bits in a buffer
1819 {
1820 // %%%% workspace merge brought two timers together for one job
1821 TracePhase t2a("output", &_t_output, true);
1822 NOT_PRODUCT( TraceTime t2b(NULL, &_t_codeGeneration, TimeCompiler, false); )
1823 Output();
1824 }
1825
1826 print_method("Final Code");
1827
1828 // He's dead, Jim.
1829 _cfg = (PhaseCFG*)0xdeadbeef;
1830 _regalloc = (PhaseChaitin*)0xdeadbeef;
1831 }
1832
1833
1834 //------------------------------dump_asm---------------------------------------
1835 // Dump formatted assembly
1836 #ifndef PRODUCT
1837 void Compile::dump_asm(int *pcs, uint pc_limit) {
1838 bool cut_short = false;
1839 tty->print_cr("#");
1840 tty->print("# "); _tf->dump(); tty->cr();
1841 tty->print_cr("#");
1842
1843 // For all blocks
1844 int pc = 0x0; // Program counter
1845 char starts_bundle = ' ';
1846 _regalloc->dump_frame();
1847
1848 Node *n = NULL;
1849 for( uint i=0; i<_cfg->_num_blocks; i++ ) {
1850 if (VMThread::should_terminate()) { cut_short = true; break; }
1851 Block *b = _cfg->_blocks[i];
1852 if (b->is_connector() && !Verbose) continue;
1853 n = b->_nodes[0];
1854 if (pcs && n->_idx < pc_limit)
1855 tty->print("%3.3x ", pcs[n->_idx]);
1856 else
1857 tty->print(" ");
1858 b->dump_head( &_cfg->_bbs );
1859 if (b->is_connector()) {
1860 tty->print_cr(" # Empty connector block");
1861 } else if (b->num_preds() == 2 && b->pred(1)->is_CatchProj() && b->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
1862 tty->print_cr(" # Block is sole successor of call");
1863 }
1864
1865 // For all instructions
1866 Node *delay = NULL;
1867 for( uint j = 0; j<b->_nodes.size(); j++ ) {
1868 if (VMThread::should_terminate()) { cut_short = true; break; }
1869 n = b->_nodes[j];
1870 if (valid_bundle_info(n)) {
1871 Bundle *bundle = node_bundling(n);
1872 if (bundle->used_in_unconditional_delay()) {
1873 delay = n;
1874 continue;
1875 }
1876 if (bundle->starts_bundle())
1877 starts_bundle = '+';
1878 }
1879
1880 if (WizardMode) n->dump();
1881
1882 if( !n->is_Region() && // Dont print in the Assembly
1883 !n->is_Phi() && // a few noisely useless nodes
1884 !n->is_Proj() &&
1885 !n->is_MachTemp() &&
1886 !n->is_SafePointScalarObject() &&
1887 !n->is_Catch() && // Would be nice to print exception table targets
1888 !n->is_MergeMem() && // Not very interesting
1889 !n->is_top() && // Debug info table constants
1890 !(n->is_Con() && !n->is_Mach())// Debug info table constants
1891 ) {
1892 if (pcs && n->_idx < pc_limit)
1893 tty->print("%3.3x", pcs[n->_idx]);
1894 else
1895 tty->print(" ");
1896 tty->print(" %c ", starts_bundle);
1897 starts_bundle = ' ';
1898 tty->print("\t");
1899 n->format(_regalloc, tty);
1900 tty->cr();
1901 }
1902
1903 // If we have an instruction with a delay slot, and have seen a delay,
1904 // then back up and print it
1905 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
1906 assert(delay != NULL, "no unconditional delay instruction");
1907 if (WizardMode) delay->dump();
1908
1909 if (node_bundling(delay)->starts_bundle())
1910 starts_bundle = '+';
1911 if (pcs && n->_idx < pc_limit)
1912 tty->print("%3.3x", pcs[n->_idx]);
1913 else
1914 tty->print(" ");
1915 tty->print(" %c ", starts_bundle);
1916 starts_bundle = ' ';
1917 tty->print("\t");
1918 delay->format(_regalloc, tty);
1919 tty->print_cr("");
1920 delay = NULL;
1921 }
1922
1923 // Dump the exception table as well
1924 if( n->is_Catch() && (Verbose || WizardMode) ) {
1925 // Print the exception table for this offset
1926 _handler_table.print_subtable_for(pc);
1927 }
1928 }
1929
1930 if (pcs && n->_idx < pc_limit)
1931 tty->print_cr("%3.3x", pcs[n->_idx]);
1932 else
1933 tty->print_cr("");
1934
1935 assert(cut_short || delay == NULL, "no unconditional delay branch");
1936
1937 } // End of per-block dump
1938 tty->print_cr("");
1939
1940 if (cut_short) tty->print_cr("*** disassembly is cut short ***");
1941 }
1942 #endif
1943
1944 //------------------------------Final_Reshape_Counts---------------------------
1945 // This class defines counters to help identify when a method
1946 // may/must be executed using hardware with only 24-bit precision.
1947 struct Final_Reshape_Counts : public StackObj {
1948 int _call_count; // count non-inlined 'common' calls
1949 int _float_count; // count float ops requiring 24-bit precision
1950 int _double_count; // count double ops requiring more precision
1951 int _java_call_count; // count non-inlined 'java' calls
1952 int _inner_loop_count; // count loops which need alignment
1953 VectorSet _visited; // Visitation flags
1954 Node_List _tests; // Set of IfNodes & PCTableNodes
1955
1956 Final_Reshape_Counts() :
1957 _call_count(0), _float_count(0), _double_count(0),
1958 _java_call_count(0), _inner_loop_count(0),
1959 _visited( Thread::current()->resource_area() ) { }
1960
1961 void inc_call_count () { _call_count ++; }
1962 void inc_float_count () { _float_count ++; }
1963 void inc_double_count() { _double_count++; }
1964 void inc_java_call_count() { _java_call_count++; }
1965 void inc_inner_loop_count() { _inner_loop_count++; }
1966
1967 int get_call_count () const { return _call_count ; }
1968 int get_float_count () const { return _float_count ; }
1969 int get_double_count() const { return _double_count; }
1970 int get_java_call_count() const { return _java_call_count; }
1971 int get_inner_loop_count() const { return _inner_loop_count; }
1972 };
1973
1974 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
1975 ciInstanceKlass *k = tp->klass()->as_instance_klass();
1976 // Make sure the offset goes inside the instance layout.
1977 return k->contains_field_offset(tp->offset());
1978 // Note that OffsetBot and OffsetTop are very negative.
1979 }
1980
1981 //------------------------------final_graph_reshaping_impl----------------------
1982 // Implement items 1-5 from final_graph_reshaping below.
1983 static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
1984
1985 if ( n->outcnt() == 0 ) return; // dead node
1986 uint nop = n->Opcode();
1987
1988 // Check for 2-input instruction with "last use" on right input.
1989 // Swap to left input. Implements item (2).
1990 if( n->req() == 3 && // two-input instruction
1991 n->in(1)->outcnt() > 1 && // left use is NOT a last use
1992 (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
1993 n->in(2)->outcnt() == 1 &&// right use IS a last use
1994 !n->in(2)->is_Con() ) { // right use is not a constant
1995 // Check for commutative opcode
1996 switch( nop ) {
1997 case Op_AddI: case Op_AddF: case Op_AddD: case Op_AddL:
1998 case Op_MaxI: case Op_MinI:
1999 case Op_MulI: case Op_MulF: case Op_MulD: case Op_MulL:
2000 case Op_AndL: case Op_XorL: case Op_OrL:
2001 case Op_AndI: case Op_XorI: case Op_OrI: {
2002 // Move "last use" input to left by swapping inputs
2003 n->swap_edges(1, 2);
2004 break;
2005 }
2006 default:
2007 break;
2008 }
2009 }
2010
2011 #ifdef ASSERT
2012 if( n->is_Mem() ) {
2013 Compile* C = Compile::current();
2014 int alias_idx = C->get_alias_index(n->as_Mem()->adr_type());
2015 assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
2016 // oop will be recorded in oop map if load crosses safepoint
2017 n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
2018 LoadNode::is_immutable_value(n->in(MemNode::Address))),
2019 "raw memory operations should have control edge");
2020 }
2021 #endif
2022 // Count FPU ops and common calls, implements item (3)
2023 switch( nop ) {
2024 // Count all float operations that may use FPU
2025 case Op_AddF:
2026 case Op_SubF:
2027 case Op_MulF:
2028 case Op_DivF:
2029 case Op_NegF:
2030 case Op_ModF:
2031 case Op_ConvI2F:
2032 case Op_ConF:
2033 case Op_CmpF:
2034 case Op_CmpF3:
2035 // case Op_ConvL2F: // longs are split into 32-bit halves
2036 frc.inc_float_count();
2037 break;
2038
2039 case Op_ConvF2D:
2040 case Op_ConvD2F:
2041 frc.inc_float_count();
2042 frc.inc_double_count();
2043 break;
2044
2045 // Count all double operations that may use FPU
2046 case Op_AddD:
2047 case Op_SubD:
2048 case Op_MulD:
2049 case Op_DivD:
2050 case Op_NegD:
2051 case Op_ModD:
2052 case Op_ConvI2D:
2053 case Op_ConvD2I:
2054 // case Op_ConvL2D: // handled by leaf call
2055 // case Op_ConvD2L: // handled by leaf call
2056 case Op_ConD:
2057 case Op_CmpD:
2058 case Op_CmpD3:
2059 frc.inc_double_count();
2060 break;
2061 case Op_Opaque1: // Remove Opaque Nodes before matching
2062 case Op_Opaque2: // Remove Opaque Nodes before matching
2063 n->subsume_by(n->in(1));
2064 break;
2065 case Op_CallStaticJava:
2066 case Op_CallJava:
2067 case Op_CallDynamicJava:
2068 frc.inc_java_call_count(); // Count java call site;
2069 case Op_CallRuntime:
2070 case Op_CallLeaf:
2071 case Op_CallLeafNoFP: {
2072 assert( n->is_Call(), "" );
2073 CallNode *call = n->as_Call();
2074 // Count call sites where the FP mode bit would have to be flipped.
2075 // Do not count uncommon runtime calls:
2076 // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
2077 // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
2078 if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
2079 frc.inc_call_count(); // Count the call site
2080 } else { // See if uncommon argument is shared
2081 Node *n = call->in(TypeFunc::Parms);
2082 int nop = n->Opcode();
2083 // Clone shared simple arguments to uncommon calls, item (1).
2084 if( n->outcnt() > 1 &&
2085 !n->is_Proj() &&
2086 nop != Op_CreateEx &&
2087 nop != Op_CheckCastPP &&
2088 nop != Op_DecodeN &&
2089 !n->is_Mem() ) {
2090 Node *x = n->clone();
2091 call->set_req( TypeFunc::Parms, x );
2092 }
2093 }
2094 break;
2095 }
2096
2097 case Op_StoreD:
2098 case Op_LoadD:
2099 case Op_LoadD_unaligned:
2100 frc.inc_double_count();
2101 goto handle_mem;
2102 case Op_StoreF:
2103 case Op_LoadF:
2104 frc.inc_float_count();
2105 goto handle_mem;
2106
2107 case Op_StoreB:
2108 case Op_StoreC:
2109 case Op_StoreCM:
2110 case Op_StorePConditional:
2111 case Op_StoreI:
2112 case Op_StoreL:
2113 case Op_StoreIConditional:
2114 case Op_StoreLConditional:
2115 case Op_CompareAndSwapI:
2116 case Op_CompareAndSwapL:
2117 case Op_CompareAndSwapP:
2118 case Op_CompareAndSwapN:
2119 case Op_StoreP:
2120 case Op_StoreN:
2121 case Op_LoadB:
2122 case Op_LoadUB:
2123 case Op_LoadUS:
2124 case Op_LoadI:
2125 case Op_LoadUI2L:
2126 case Op_LoadKlass:
2127 case Op_LoadNKlass:
2128 case Op_LoadL:
2129 case Op_LoadL_unaligned:
2130 case Op_LoadPLocked:
2131 case Op_LoadLLocked:
2132 case Op_LoadP:
2133 case Op_LoadN:
2134 case Op_LoadRange:
2135 case Op_LoadS: {
2136 handle_mem:
2137 #ifdef ASSERT
2138 if( VerifyOptoOopOffsets ) {
2139 assert( n->is_Mem(), "" );
2140 MemNode *mem = (MemNode*)n;
2141 // Check to see if address types have grounded out somehow.
2142 const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
2143 assert( !tp || oop_offset_is_sane(tp), "" );
2144 }
2145 #endif
2146 break;
2147 }
2148
2149 case Op_AddP: { // Assert sane base pointers
2150 Node *addp = n->in(AddPNode::Address);
2151 assert( !addp->is_AddP() ||
2152 addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
2153 addp->in(AddPNode::Base) == n->in(AddPNode::Base),
2154 "Base pointers must match" );
2155 #ifdef _LP64
2156 if (UseCompressedOops &&
2157 addp->Opcode() == Op_ConP &&
2158 addp == n->in(AddPNode::Base) &&
2159 n->in(AddPNode::Offset)->is_Con()) {
2160 // Use addressing with narrow klass to load with offset on x86.
2161 // On sparc loading 32-bits constant and decoding it have less
2162 // instructions (4) then load 64-bits constant (7).
2163 // Do this transformation here since IGVN will convert ConN back to ConP.
2164 const Type* t = addp->bottom_type();
2165 if (t->isa_oopptr()) {
2166 Node* nn = NULL;
2167
2168 // Look for existing ConN node of the same exact type.
2169 Compile* C = Compile::current();
2170 Node* r = C->root();
2171 uint cnt = r->outcnt();
2172 for (uint i = 0; i < cnt; i++) {
2173 Node* m = r->raw_out(i);
2174 if (m!= NULL && m->Opcode() == Op_ConN &&
2175 m->bottom_type()->make_ptr() == t) {
2176 nn = m;
2177 break;
2178 }
2179 }
2180 if (nn != NULL) {
2181 // Decode a narrow oop to match address
2182 // [R12 + narrow_oop_reg<<3 + offset]
2183 nn = new (C, 2) DecodeNNode(nn, t);
2184 n->set_req(AddPNode::Base, nn);
2185 n->set_req(AddPNode::Address, nn);
2186 if (addp->outcnt() == 0) {
2187 addp->disconnect_inputs(NULL);
2188 }
2189 }
2190 }
2191 }
2192 #endif
2193 break;
2194 }
2195
2196 #ifdef _LP64
2197 case Op_CastPP:
2198 if (n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
2199 Compile* C = Compile::current();
2200 Node* in1 = n->in(1);
2201 const Type* t = n->bottom_type();
2202 Node* new_in1 = in1->clone();
2203 new_in1->as_DecodeN()->set_type(t);
2204
2205 if (!Matcher::narrow_oop_use_complex_address()) {
2206 //
2207 // x86, ARM and friends can handle 2 adds in addressing mode
2208 // and Matcher can fold a DecodeN node into address by using
2209 // a narrow oop directly and do implicit NULL check in address:
2210 //
2211 // [R12 + narrow_oop_reg<<3 + offset]
2212 // NullCheck narrow_oop_reg
2213 //
2214 // On other platforms (Sparc) we have to keep new DecodeN node and
2215 // use it to do implicit NULL check in address:
2216 //
2217 // decode_not_null narrow_oop_reg, base_reg
2218 // [base_reg + offset]
2219 // NullCheck base_reg
2220 //
2221 // Pin the new DecodeN node to non-null path on these platform (Sparc)
2222 // to keep the information to which NULL check the new DecodeN node
2223 // corresponds to use it as value in implicit_null_check().
2224 //
2225 new_in1->set_req(0, n->in(0));
2226 }
2227
2228 n->subsume_by(new_in1);
2229 if (in1->outcnt() == 0) {
2230 in1->disconnect_inputs(NULL);
2231 }
2232 }
2233 break;
2234
2235 case Op_CmpP:
2236 // Do this transformation here to preserve CmpPNode::sub() and
2237 // other TypePtr related Ideal optimizations (for example, ptr nullness).
2238 if (n->in(1)->is_DecodeN() || n->in(2)->is_DecodeN()) {
2239 Node* in1 = n->in(1);
2240 Node* in2 = n->in(2);
2241 if (!in1->is_DecodeN()) {
2242 in2 = in1;
2243 in1 = n->in(2);
2244 }
2245 assert(in1->is_DecodeN(), "sanity");
2246
2247 Compile* C = Compile::current();
2248 Node* new_in2 = NULL;
2249 if (in2->is_DecodeN()) {
2250 new_in2 = in2->in(1);
2251 } else if (in2->Opcode() == Op_ConP) {
2252 const Type* t = in2->bottom_type();
2253 if (t == TypePtr::NULL_PTR) {
2254 // Don't convert CmpP null check into CmpN if compressed
2255 // oops implicit null check is not generated.
2256 // This will allow to generate normal oop implicit null check.
2257 if (Matcher::gen_narrow_oop_implicit_null_checks())
2258 new_in2 = ConNode::make(C, TypeNarrowOop::NULL_PTR);
2259 //
2260 // This transformation together with CastPP transformation above
2261 // will generated code for implicit NULL checks for compressed oops.
2262 //
2263 // The original code after Optimize()
2264 //
2265 // LoadN memory, narrow_oop_reg
2266 // decode narrow_oop_reg, base_reg
2267 // CmpP base_reg, NULL
2268 // CastPP base_reg // NotNull
2269 // Load [base_reg + offset], val_reg
2270 //
2271 // after these transformations will be
2272 //
2273 // LoadN memory, narrow_oop_reg
2274 // CmpN narrow_oop_reg, NULL
2275 // decode_not_null narrow_oop_reg, base_reg
2276 // Load [base_reg + offset], val_reg
2277 //
2278 // and the uncommon path (== NULL) will use narrow_oop_reg directly
2279 // since narrow oops can be used in debug info now (see the code in
2280 // final_graph_reshaping_walk()).
2281 //
2282 // At the end the code will be matched to
2283 // on x86:
2284 //
2285 // Load_narrow_oop memory, narrow_oop_reg
2286 // Load [R12 + narrow_oop_reg<<3 + offset], val_reg
2287 // NullCheck narrow_oop_reg
2288 //
2289 // and on sparc:
2290 //
2291 // Load_narrow_oop memory, narrow_oop_reg
2292 // decode_not_null narrow_oop_reg, base_reg
2293 // Load [base_reg + offset], val_reg
2294 // NullCheck base_reg
2295 //
2296 } else if (t->isa_oopptr()) {
2297 new_in2 = ConNode::make(C, t->make_narrowoop());
2298 }
2299 }
2300 if (new_in2 != NULL) {
2301 Node* cmpN = new (C, 3) CmpNNode(in1->in(1), new_in2);
2302 n->subsume_by( cmpN );
2303 if (in1->outcnt() == 0) {
2304 in1->disconnect_inputs(NULL);
2305 }
2306 if (in2->outcnt() == 0) {
2307 in2->disconnect_inputs(NULL);
2308 }
2309 }
2310 }
2311 break;
2312
2313 case Op_DecodeN:
2314 assert(!n->in(1)->is_EncodeP(), "should be optimized out");
2315 // DecodeN could be pinned when it can't be fold into
2316 // an address expression, see the code for Op_CastPP above.
2317 assert(n->in(0) == NULL || !Matcher::narrow_oop_use_complex_address(), "no control");
2318 break;
2319
2320 case Op_EncodeP: {
2321 Node* in1 = n->in(1);
2322 if (in1->is_DecodeN()) {
2323 n->subsume_by(in1->in(1));
2324 } else if (in1->Opcode() == Op_ConP) {
2325 Compile* C = Compile::current();
2326 const Type* t = in1->bottom_type();
2327 if (t == TypePtr::NULL_PTR) {
2328 n->subsume_by(ConNode::make(C, TypeNarrowOop::NULL_PTR));
2329 } else if (t->isa_oopptr()) {
2330 n->subsume_by(ConNode::make(C, t->make_narrowoop()));
2331 }
2332 }
2333 if (in1->outcnt() == 0) {
2334 in1->disconnect_inputs(NULL);
2335 }
2336 break;
2337 }
2338
2339 case Op_Proj: {
2340 if (OptimizeStringConcat) {
2341 ProjNode* p = n->as_Proj();
2342 if (p->_is_io_use) {
2343 // Separate projections were used for the exception path which
2344 // are normally removed by a late inline. If it wasn't inlined
2345 // then they will hang around and should just be replaced with
2346 // the original one.
2347 Node* proj = NULL;
2348 // Replace with just one
2349 for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
2350 Node *use = i.get();
2351 if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
2352 proj = use;
2353 break;
2354 }
2355 }
2356 assert(p != NULL, "must be found");
2357 p->subsume_by(proj);
2358 }
2359 }
2360 break;
2361 }
2362
2363 case Op_Phi:
2364 if (n->as_Phi()->bottom_type()->isa_narrowoop()) {
2365 // The EncodeP optimization may create Phi with the same edges
2366 // for all paths. It is not handled well by Register Allocator.
2367 Node* unique_in = n->in(1);
2368 assert(unique_in != NULL, "");
2369 uint cnt = n->req();
2370 for (uint i = 2; i < cnt; i++) {
2371 Node* m = n->in(i);
2372 assert(m != NULL, "");
2373 if (unique_in != m)
2374 unique_in = NULL;
2375 }
2376 if (unique_in != NULL) {
2377 n->subsume_by(unique_in);
2378 }
2379 }
2380 break;
2381
2382 #endif
2383
2384 case Op_ModI:
2385 if (UseDivMod) {
2386 // Check if a%b and a/b both exist
2387 Node* d = n->find_similar(Op_DivI);
2388 if (d) {
2389 // Replace them with a fused divmod if supported
2390 Compile* C = Compile::current();
2391 if (Matcher::has_match_rule(Op_DivModI)) {
2392 DivModINode* divmod = DivModINode::make(C, n);
2393 d->subsume_by(divmod->div_proj());
2394 n->subsume_by(divmod->mod_proj());
2395 } else {
2396 // replace a%b with a-((a/b)*b)
2397 Node* mult = new (C, 3) MulINode(d, d->in(2));
2398 Node* sub = new (C, 3) SubINode(d->in(1), mult);
2399 n->subsume_by( sub );
2400 }
2401 }
2402 }
2403 break;
2404
2405 case Op_ModL:
2406 if (UseDivMod) {
2407 // Check if a%b and a/b both exist
2408 Node* d = n->find_similar(Op_DivL);
2409 if (d) {
2410 // Replace them with a fused divmod if supported
2411 Compile* C = Compile::current();
2412 if (Matcher::has_match_rule(Op_DivModL)) {
2413 DivModLNode* divmod = DivModLNode::make(C, n);
2414 d->subsume_by(divmod->div_proj());
2415 n->subsume_by(divmod->mod_proj());
2416 } else {
2417 // replace a%b with a-((a/b)*b)
2418 Node* mult = new (C, 3) MulLNode(d, d->in(2));
2419 Node* sub = new (C, 3) SubLNode(d->in(1), mult);
2420 n->subsume_by( sub );
2421 }
2422 }
2423 }
2424 break;
2425
2426 case Op_Load16B:
2427 case Op_Load8B:
2428 case Op_Load4B:
2429 case Op_Load8S:
2430 case Op_Load4S:
2431 case Op_Load2S:
2432 case Op_Load8C:
2433 case Op_Load4C:
2434 case Op_Load2C:
2435 case Op_Load4I:
2436 case Op_Load2I:
2437 case Op_Load2L:
2438 case Op_Load4F:
2439 case Op_Load2F:
2440 case Op_Load2D:
2441 case Op_Store16B:
2442 case Op_Store8B:
2443 case Op_Store4B:
2444 case Op_Store8C:
2445 case Op_Store4C:
2446 case Op_Store2C:
2447 case Op_Store4I:
2448 case Op_Store2I:
2449 case Op_Store2L:
2450 case Op_Store4F:
2451 case Op_Store2F:
2452 case Op_Store2D:
2453 break;
2454
2455 case Op_PackB:
2456 case Op_PackS:
2457 case Op_PackC:
2458 case Op_PackI:
2459 case Op_PackF:
2460 case Op_PackL:
2461 case Op_PackD:
2462 if (n->req()-1 > 2) {
2463 // Replace many operand PackNodes with a binary tree for matching
2464 PackNode* p = (PackNode*) n;
2465 Node* btp = p->binaryTreePack(Compile::current(), 1, n->req());
2466 n->subsume_by(btp);
2467 }
2468 break;
2469 case Op_Loop:
2470 case Op_CountedLoop:
2471 if (n->as_Loop()->is_inner_loop()) {
2472 frc.inc_inner_loop_count();
2473 }
2474 break;
2475 default:
2476 assert( !n->is_Call(), "" );
2477 assert( !n->is_Mem(), "" );
2478 break;
2479 }
2480
2481 // Collect CFG split points
2482 if (n->is_MultiBranch())
2483 frc._tests.push(n);
2484 }
2485
2486 //------------------------------final_graph_reshaping_walk---------------------
2487 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
2488 // requires that the walk visits a node's inputs before visiting the node.
2489 static void final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
2490 ResourceArea *area = Thread::current()->resource_area();
2491 Unique_Node_List sfpt(area);
2492
2493 frc._visited.set(root->_idx); // first, mark node as visited
2494 uint cnt = root->req();
2495 Node *n = root;
2496 uint i = 0;
2497 while (true) {
2498 if (i < cnt) {
2499 // Place all non-visited non-null inputs onto stack
2500 Node* m = n->in(i);
2501 ++i;
2502 if (m != NULL && !frc._visited.test_set(m->_idx)) {
2503 if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL)
2504 sfpt.push(m);
2505 cnt = m->req();
2506 nstack.push(n, i); // put on stack parent and next input's index
2507 n = m;
2508 i = 0;
2509 }
2510 } else {
2511 // Now do post-visit work
2512 final_graph_reshaping_impl( n, frc );
2513 if (nstack.is_empty())
2514 break; // finished
2515 n = nstack.node(); // Get node from stack
2516 cnt = n->req();
2517 i = nstack.index();
2518 nstack.pop(); // Shift to the next node on stack
2519 }
2520 }
2521
2522 // Skip next transformation if compressed oops are not used.
2523 if (!UseCompressedOops || !Matcher::gen_narrow_oop_implicit_null_checks())
2524 return;
2525
2526 // Go over safepoints nodes to skip DecodeN nodes for debug edges.
2527 // It could be done for an uncommon traps or any safepoints/calls
2528 // if the DecodeN node is referenced only in a debug info.
2529 while (sfpt.size() > 0) {
2530 n = sfpt.pop();
2531 JVMState *jvms = n->as_SafePoint()->jvms();
2532 assert(jvms != NULL, "sanity");
2533 int start = jvms->debug_start();
2534 int end = n->req();
2535 bool is_uncommon = (n->is_CallStaticJava() &&
2536 n->as_CallStaticJava()->uncommon_trap_request() != 0);
2537 for (int j = start; j < end; j++) {
2538 Node* in = n->in(j);
2539 if (in->is_DecodeN()) {
2540 bool safe_to_skip = true;
2541 if (!is_uncommon ) {
2542 // Is it safe to skip?
2543 for (uint i = 0; i < in->outcnt(); i++) {
2544 Node* u = in->raw_out(i);
2545 if (!u->is_SafePoint() ||
2546 u->is_Call() && u->as_Call()->has_non_debug_use(n)) {
2547 safe_to_skip = false;
2548 }
2549 }
2550 }
2551 if (safe_to_skip) {
2552 n->set_req(j, in->in(1));
2553 }
2554 if (in->outcnt() == 0) {
2555 in->disconnect_inputs(NULL);
2556 }
2557 }
2558 }
2559 }
2560 }
2561
2562 //------------------------------final_graph_reshaping--------------------------
2563 // Final Graph Reshaping.
2564 //
2565 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
2566 // and not commoned up and forced early. Must come after regular
2567 // optimizations to avoid GVN undoing the cloning. Clone constant
2568 // inputs to Loop Phis; these will be split by the allocator anyways.
2569 // Remove Opaque nodes.
2570 // (2) Move last-uses by commutative operations to the left input to encourage
2571 // Intel update-in-place two-address operations and better register usage
2572 // on RISCs. Must come after regular optimizations to avoid GVN Ideal
2573 // calls canonicalizing them back.
2574 // (3) Count the number of double-precision FP ops, single-precision FP ops
2575 // and call sites. On Intel, we can get correct rounding either by
2576 // forcing singles to memory (requires extra stores and loads after each
2577 // FP bytecode) or we can set a rounding mode bit (requires setting and
2578 // clearing the mode bit around call sites). The mode bit is only used
2579 // if the relative frequency of single FP ops to calls is low enough.
2580 // This is a key transform for SPEC mpeg_audio.
2581 // (4) Detect infinite loops; blobs of code reachable from above but not
2582 // below. Several of the Code_Gen algorithms fail on such code shapes,
2583 // so we simply bail out. Happens a lot in ZKM.jar, but also happens
2584 // from time to time in other codes (such as -Xcomp finalizer loops, etc).
2585 // Detection is by looking for IfNodes where only 1 projection is
2586 // reachable from below or CatchNodes missing some targets.
2587 // (5) Assert for insane oop offsets in debug mode.
2588
2589 bool Compile::final_graph_reshaping() {
2590 // an infinite loop may have been eliminated by the optimizer,
2591 // in which case the graph will be empty.
2592 if (root()->req() == 1) {
2593 record_method_not_compilable("trivial infinite loop");
2594 return true;
2595 }
2596
2597 Final_Reshape_Counts frc;
2598
2599 // Visit everybody reachable!
2600 // Allocate stack of size C->unique()/2 to avoid frequent realloc
2601 Node_Stack nstack(unique() >> 1);
2602 final_graph_reshaping_walk(nstack, root(), frc);
2603
2604 // Check for unreachable (from below) code (i.e., infinite loops).
2605 for( uint i = 0; i < frc._tests.size(); i++ ) {
2606 MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
2607 // Get number of CFG targets.
2608 // Note that PCTables include exception targets after calls.
2609 uint required_outcnt = n->required_outcnt();
2610 if (n->outcnt() != required_outcnt) {
2611 // Check for a few special cases. Rethrow Nodes never take the
2612 // 'fall-thru' path, so expected kids is 1 less.
2613 if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
2614 if (n->in(0)->in(0)->is_Call()) {
2615 CallNode *call = n->in(0)->in(0)->as_Call();
2616 if (call->entry_point() == OptoRuntime::rethrow_stub()) {
2617 required_outcnt--; // Rethrow always has 1 less kid
2618 } else if (call->req() > TypeFunc::Parms &&
2619 call->is_CallDynamicJava()) {
2620 // Check for null receiver. In such case, the optimizer has
2621 // detected that the virtual call will always result in a null
2622 // pointer exception. The fall-through projection of this CatchNode
2623 // will not be populated.
2624 Node *arg0 = call->in(TypeFunc::Parms);
2625 if (arg0->is_Type() &&
2626 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
2627 required_outcnt--;
2628 }
2629 } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
2630 call->req() > TypeFunc::Parms+1 &&
2631 call->is_CallStaticJava()) {
2632 // Check for negative array length. In such case, the optimizer has
2633 // detected that the allocation attempt will always result in an
2634 // exception. There is no fall-through projection of this CatchNode .
2635 Node *arg1 = call->in(TypeFunc::Parms+1);
2636 if (arg1->is_Type() &&
2637 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
2638 required_outcnt--;
2639 }
2640 }
2641 }
2642 }
2643 // Recheck with a better notion of 'required_outcnt'
2644 if (n->outcnt() != required_outcnt) {
2645 record_method_not_compilable("malformed control flow");
2646 return true; // Not all targets reachable!
2647 }
2648 }
2649 // Check that I actually visited all kids. Unreached kids
2650 // must be infinite loops.
2651 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
2652 if (!frc._visited.test(n->fast_out(j)->_idx)) {
2653 record_method_not_compilable("infinite loop");
2654 return true; // Found unvisited kid; must be unreach
2655 }
2656 }
2657
2658 // If original bytecodes contained a mixture of floats and doubles
2659 // check if the optimizer has made it homogenous, item (3).
2660 if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
2661 frc.get_float_count() > 32 &&
2662 frc.get_double_count() == 0 &&
2663 (10 * frc.get_call_count() < frc.get_float_count()) ) {
2664 set_24_bit_selection_and_mode( false, true );
2665 }
2666
2667 set_java_calls(frc.get_java_call_count());
2668 set_inner_loops(frc.get_inner_loop_count());
2669
2670 // No infinite loops, no reason to bail out.
2671 return false;
2672 }
2673
2674 //-----------------------------too_many_traps----------------------------------
2675 // Report if there are too many traps at the current method and bci.
2676 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
2677 bool Compile::too_many_traps(ciMethod* method,
2678 int bci,
2679 Deoptimization::DeoptReason reason) {
2680 ciMethodData* md = method->method_data();
2681 if (md->is_empty()) {
2682 // Assume the trap has not occurred, or that it occurred only
2683 // because of a transient condition during start-up in the interpreter.
2684 return false;
2685 }
2686 if (md->has_trap_at(bci, reason) != 0) {
2687 // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
2688 // Also, if there are multiple reasons, or if there is no per-BCI record,
2689 // assume the worst.
2690 if (log())
2691 log()->elem("observe trap='%s' count='%d'",
2692 Deoptimization::trap_reason_name(reason),
2693 md->trap_count(reason));
2694 return true;
2695 } else {
2696 // Ignore method/bci and see if there have been too many globally.
2697 return too_many_traps(reason, md);
2698 }
2699 }
2700
2701 // Less-accurate variant which does not require a method and bci.
2702 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
2703 ciMethodData* logmd) {
2704 if (trap_count(reason) >= (uint)PerMethodTrapLimit) {
2705 // Too many traps globally.
2706 // Note that we use cumulative trap_count, not just md->trap_count.
2707 if (log()) {
2708 int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
2709 log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
2710 Deoptimization::trap_reason_name(reason),
2711 mcount, trap_count(reason));
2712 }
2713 return true;
2714 } else {
2715 // The coast is clear.
2716 return false;
2717 }
2718 }
2719
2720 //--------------------------too_many_recompiles--------------------------------
2721 // Report if there are too many recompiles at the current method and bci.
2722 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
2723 // Is not eager to return true, since this will cause the compiler to use
2724 // Action_none for a trap point, to avoid too many recompilations.
2725 bool Compile::too_many_recompiles(ciMethod* method,
2726 int bci,
2727 Deoptimization::DeoptReason reason) {
2728 ciMethodData* md = method->method_data();
2729 if (md->is_empty()) {
2730 // Assume the trap has not occurred, or that it occurred only
2731 // because of a transient condition during start-up in the interpreter.
2732 return false;
2733 }
2734 // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
2735 uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
2736 uint m_cutoff = (uint) PerMethodRecompilationCutoff / 2 + 1; // not zero
2737 Deoptimization::DeoptReason per_bc_reason
2738 = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
2739 if ((per_bc_reason == Deoptimization::Reason_none
2740 || md->has_trap_at(bci, reason) != 0)
2741 // The trap frequency measure we care about is the recompile count:
2742 && md->trap_recompiled_at(bci)
2743 && md->overflow_recompile_count() >= bc_cutoff) {
2744 // Do not emit a trap here if it has already caused recompilations.
2745 // Also, if there are multiple reasons, or if there is no per-BCI record,
2746 // assume the worst.
2747 if (log())
2748 log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
2749 Deoptimization::trap_reason_name(reason),
2750 md->trap_count(reason),
2751 md->overflow_recompile_count());
2752 return true;
2753 } else if (trap_count(reason) != 0
2754 && decompile_count() >= m_cutoff) {
2755 // Too many recompiles globally, and we have seen this sort of trap.
2756 // Use cumulative decompile_count, not just md->decompile_count.
2757 if (log())
2758 log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
2759 Deoptimization::trap_reason_name(reason),
2760 md->trap_count(reason), trap_count(reason),
2761 md->decompile_count(), decompile_count());
2762 return true;
2763 } else {
2764 // The coast is clear.
2765 return false;
2766 }
2767 }
2768
2769
2770 #ifndef PRODUCT
2771 //------------------------------verify_graph_edges---------------------------
2772 // Walk the Graph and verify that there is a one-to-one correspondence
2773 // between Use-Def edges and Def-Use edges in the graph.
2774 void Compile::verify_graph_edges(bool no_dead_code) {
2775 if (VerifyGraphEdges) {
2776 ResourceArea *area = Thread::current()->resource_area();
2777 Unique_Node_List visited(area);
2778 // Call recursive graph walk to check edges
2779 _root->verify_edges(visited);
2780 if (no_dead_code) {
2781 // Now make sure that no visited node is used by an unvisited node.
2782 bool dead_nodes = 0;
2783 Unique_Node_List checked(area);
2784 while (visited.size() > 0) {
2785 Node* n = visited.pop();
2786 checked.push(n);
2787 for (uint i = 0; i < n->outcnt(); i++) {
2788 Node* use = n->raw_out(i);
2789 if (checked.member(use)) continue; // already checked
2790 if (visited.member(use)) continue; // already in the graph
2791 if (use->is_Con()) continue; // a dead ConNode is OK
2792 // At this point, we have found a dead node which is DU-reachable.
2793 if (dead_nodes++ == 0)
2794 tty->print_cr("*** Dead nodes reachable via DU edges:");
2795 use->dump(2);
2796 tty->print_cr("---");
2797 checked.push(use); // No repeats; pretend it is now checked.
2798 }
2799 }
2800 assert(dead_nodes == 0, "using nodes must be reachable from root");
2801 }
2802 }
2803 }
2804 #endif
2805
2806 // The Compile object keeps track of failure reasons separately from the ciEnv.
2807 // This is required because there is not quite a 1-1 relation between the
2808 // ciEnv and its compilation task and the Compile object. Note that one
2809 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
2810 // to backtrack and retry without subsuming loads. Other than this backtracking
2811 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
2812 // by the logic in C2Compiler.
2813 void Compile::record_failure(const char* reason) {
2814 if (log() != NULL) {
2815 log()->elem("failure reason='%s' phase='compile'", reason);
2816 }
2817 if (_failure_reason == NULL) {
2818 // Record the first failure reason.
2819 _failure_reason = reason;
2820 }
2821 if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
2822 C->print_method(_failure_reason);
2823 }
2824 _root = NULL; // flush the graph, too
2825 }
2826
2827 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator, bool dolog)
2828 : TraceTime(NULL, accumulator, false NOT_PRODUCT( || TimeCompiler ), false)
2829 {
2830 if (dolog) {
2831 C = Compile::current();
2832 _log = C->log();
2833 } else {
2834 C = NULL;
2835 _log = NULL;
2836 }
2837 if (_log != NULL) {
2838 _log->begin_head("phase name='%s' nodes='%d'", name, C->unique());
2839 _log->stamp();
2840 _log->end_head();
2841 }
2842 }
2843
2844 Compile::TracePhase::~TracePhase() {
2845 if (_log != NULL) {
2846 _log->done("phase nodes='%d'", C->unique());
2847 }
2848 }