1 /*
2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "asm/macroAssembler.hpp"
27 #include "asm/macroAssembler.inline.hpp"
28 #include "ci/ciReplay.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "code/exceptionHandlerTable.hpp"
31 #include "code/nmethod.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/compileLog.hpp"
34 #include "compiler/disassembler.hpp"
35 #include "compiler/oopMap.hpp"
36 #include "opto/addnode.hpp"
37 #include "opto/block.hpp"
38 #include "opto/c2compiler.hpp"
39 #include "opto/callGenerator.hpp"
40 #include "opto/callnode.hpp"
41 #include "opto/cfgnode.hpp"
42 #include "opto/chaitin.hpp"
43 #include "opto/compile.hpp"
44 #include "opto/connode.hpp"
45 #include "opto/divnode.hpp"
46 #include "opto/escape.hpp"
47 #include "opto/idealGraphPrinter.hpp"
48 #include "opto/loopnode.hpp"
49 #include "opto/machnode.hpp"
50 #include "opto/macro.hpp"
51 #include "opto/matcher.hpp"
52 #include "opto/mathexactnode.hpp"
53 #include "opto/memnode.hpp"
54 #include "opto/mulnode.hpp"
55 #include "opto/narrowptrnode.hpp"
56 #include "opto/node.hpp"
57 #include "opto/opcodes.hpp"
58 #include "opto/output.hpp"
59 #include "opto/parse.hpp"
60 #include "opto/phaseX.hpp"
61 #include "opto/rootnode.hpp"
62 #include "opto/runtime.hpp"
63 #include "opto/stringopts.hpp"
64 #include "opto/type.hpp"
65 #include "opto/vectornode.hpp"
66 #include "runtime/arguments.hpp"
67 #include "runtime/signature.hpp"
68 #include "runtime/stubRoutines.hpp"
69 #include "runtime/timer.hpp"
70 #include "trace/tracing.hpp"
71 #include "utilities/copy.hpp"
72
73
74 // -------------------- Compile::mach_constant_base_node -----------------------
75 // Constant table base node singleton.
76 MachConstantBaseNode* Compile::mach_constant_base_node() {
77 if (_mach_constant_base_node == NULL) {
78 _mach_constant_base_node = new MachConstantBaseNode();
79 _mach_constant_base_node->add_req(C->root());
80 }
81 return _mach_constant_base_node;
82 }
83
84
85 /// Support for intrinsics.
86
87 // Return the index at which m must be inserted (or already exists).
88 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
89 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual) {
90 #ifdef ASSERT
91 for (int i = 1; i < _intrinsics->length(); i++) {
92 CallGenerator* cg1 = _intrinsics->at(i-1);
93 CallGenerator* cg2 = _intrinsics->at(i);
94 assert(cg1->method() != cg2->method()
95 ? cg1->method() < cg2->method()
96 : cg1->is_virtual() < cg2->is_virtual(),
97 "compiler intrinsics list must stay sorted");
98 }
99 #endif
100 // Binary search sorted list, in decreasing intervals [lo, hi].
101 int lo = 0, hi = _intrinsics->length()-1;
102 while (lo <= hi) {
103 int mid = (uint)(hi + lo) / 2;
104 ciMethod* mid_m = _intrinsics->at(mid)->method();
105 if (m < mid_m) {
106 hi = mid-1;
107 } else if (m > mid_m) {
108 lo = mid+1;
109 } else {
110 // look at minor sort key
111 bool mid_virt = _intrinsics->at(mid)->is_virtual();
112 if (is_virtual < mid_virt) {
113 hi = mid-1;
114 } else if (is_virtual > mid_virt) {
115 lo = mid+1;
116 } else {
117 return mid; // exact match
118 }
119 }
120 }
121 return lo; // inexact match
122 }
123
124 void Compile::register_intrinsic(CallGenerator* cg) {
125 if (_intrinsics == NULL) {
126 _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
127 }
128 // This code is stolen from ciObjectFactory::insert.
129 // Really, GrowableArray should have methods for
130 // insert_at, remove_at, and binary_search.
131 int len = _intrinsics->length();
132 int index = intrinsic_insertion_index(cg->method(), cg->is_virtual());
133 if (index == len) {
134 _intrinsics->append(cg);
135 } else {
136 #ifdef ASSERT
137 CallGenerator* oldcg = _intrinsics->at(index);
138 assert(oldcg->method() != cg->method() || oldcg->is_virtual() != cg->is_virtual(), "don't register twice");
139 #endif
140 _intrinsics->append(_intrinsics->at(len-1));
141 int pos;
142 for (pos = len-2; pos >= index; pos--) {
143 _intrinsics->at_put(pos+1,_intrinsics->at(pos));
144 }
145 _intrinsics->at_put(index, cg);
146 }
147 assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
148 }
149
150 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
151 assert(m->is_loaded(), "don't try this on unloaded methods");
152 if (_intrinsics != NULL) {
153 int index = intrinsic_insertion_index(m, is_virtual);
154 if (index < _intrinsics->length()
155 && _intrinsics->at(index)->method() == m
156 && _intrinsics->at(index)->is_virtual() == is_virtual) {
157 return _intrinsics->at(index);
158 }
159 }
160 // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
161 if (m->intrinsic_id() != vmIntrinsics::_none &&
162 m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
163 CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
164 if (cg != NULL) {
165 // Save it for next time:
166 register_intrinsic(cg);
167 return cg;
168 } else {
169 gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
170 }
171 }
172 return NULL;
173 }
174
175 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
176 // in library_call.cpp.
177
178
179 #ifndef PRODUCT
180 // statistics gathering...
181
182 juint Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
183 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
184
185 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
186 assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
187 int oflags = _intrinsic_hist_flags[id];
188 assert(flags != 0, "what happened?");
189 if (is_virtual) {
190 flags |= _intrinsic_virtual;
191 }
192 bool changed = (flags != oflags);
193 if ((flags & _intrinsic_worked) != 0) {
194 juint count = (_intrinsic_hist_count[id] += 1);
195 if (count == 1) {
196 changed = true; // first time
197 }
198 // increment the overall count also:
199 _intrinsic_hist_count[vmIntrinsics::_none] += 1;
200 }
201 if (changed) {
202 if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
203 // Something changed about the intrinsic's virtuality.
204 if ((flags & _intrinsic_virtual) != 0) {
205 // This is the first use of this intrinsic as a virtual call.
206 if (oflags != 0) {
207 // We already saw it as a non-virtual, so note both cases.
208 flags |= _intrinsic_both;
209 }
210 } else if ((oflags & _intrinsic_both) == 0) {
211 // This is the first use of this intrinsic as a non-virtual
212 flags |= _intrinsic_both;
213 }
214 }
215 _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
216 }
217 // update the overall flags also:
218 _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
219 return changed;
220 }
221
222 static char* format_flags(int flags, char* buf) {
223 buf[0] = 0;
224 if ((flags & Compile::_intrinsic_worked) != 0) strcat(buf, ",worked");
225 if ((flags & Compile::_intrinsic_failed) != 0) strcat(buf, ",failed");
226 if ((flags & Compile::_intrinsic_disabled) != 0) strcat(buf, ",disabled");
227 if ((flags & Compile::_intrinsic_virtual) != 0) strcat(buf, ",virtual");
228 if ((flags & Compile::_intrinsic_both) != 0) strcat(buf, ",nonvirtual");
229 if (buf[0] == 0) strcat(buf, ",");
230 assert(buf[0] == ',', "must be");
231 return &buf[1];
232 }
233
234 void Compile::print_intrinsic_statistics() {
235 char flagsbuf[100];
236 ttyLocker ttyl;
237 if (xtty != NULL) xtty->head("statistics type='intrinsic'");
238 tty->print_cr("Compiler intrinsic usage:");
239 juint total = _intrinsic_hist_count[vmIntrinsics::_none];
240 if (total == 0) total = 1; // avoid div0 in case of no successes
241 #define PRINT_STAT_LINE(name, c, f) \
242 tty->print_cr(" %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
243 for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
244 vmIntrinsics::ID id = (vmIntrinsics::ID) index;
245 int flags = _intrinsic_hist_flags[id];
246 juint count = _intrinsic_hist_count[id];
247 if ((flags | count) != 0) {
248 PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
249 }
250 }
251 PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
252 if (xtty != NULL) xtty->tail("statistics");
253 }
254
255 void Compile::print_statistics() {
256 { ttyLocker ttyl;
257 if (xtty != NULL) xtty->head("statistics type='opto'");
258 Parse::print_statistics();
259 PhaseCCP::print_statistics();
260 PhaseRegAlloc::print_statistics();
261 Scheduling::print_statistics();
262 PhasePeephole::print_statistics();
263 PhaseIdealLoop::print_statistics();
264 if (xtty != NULL) xtty->tail("statistics");
265 }
266 if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
267 // put this under its own <statistics> element.
268 print_intrinsic_statistics();
269 }
270 }
271 #endif //PRODUCT
272
273 // Support for bundling info
274 Bundle* Compile::node_bundling(const Node *n) {
275 assert(valid_bundle_info(n), "oob");
276 return &_node_bundling_base[n->_idx];
277 }
278
279 bool Compile::valid_bundle_info(const Node *n) {
280 return (_node_bundling_limit > n->_idx);
281 }
282
283
284 void Compile::gvn_replace_by(Node* n, Node* nn) {
285 for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
286 Node* use = n->last_out(i);
287 bool is_in_table = initial_gvn()->hash_delete(use);
288 uint uses_found = 0;
289 for (uint j = 0; j < use->len(); j++) {
290 if (use->in(j) == n) {
291 if (j < use->req())
292 use->set_req(j, nn);
293 else
294 use->set_prec(j, nn);
295 uses_found++;
296 }
297 }
298 if (is_in_table) {
299 // reinsert into table
300 initial_gvn()->hash_find_insert(use);
301 }
302 record_for_igvn(use);
303 i -= uses_found; // we deleted 1 or more copies of this edge
304 }
305 }
306
307
308 static inline bool not_a_node(const Node* n) {
309 if (n == NULL) return true;
310 if (((intptr_t)n & 1) != 0) return true; // uninitialized, etc.
311 if (*(address*)n == badAddress) return true; // kill by Node::destruct
312 return false;
313 }
314
315 // Identify all nodes that are reachable from below, useful.
316 // Use breadth-first pass that records state in a Unique_Node_List,
317 // recursive traversal is slower.
318 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
319 int estimated_worklist_size = unique();
320 useful.map( estimated_worklist_size, NULL ); // preallocate space
321
322 // Initialize worklist
323 if (root() != NULL) { useful.push(root()); }
324 // If 'top' is cached, declare it useful to preserve cached node
325 if( cached_top_node() ) { useful.push(cached_top_node()); }
326
327 // Push all useful nodes onto the list, breadthfirst
328 for( uint next = 0; next < useful.size(); ++next ) {
329 assert( next < unique(), "Unique useful nodes < total nodes");
330 Node *n = useful.at(next);
331 uint max = n->len();
332 for( uint i = 0; i < max; ++i ) {
333 Node *m = n->in(i);
334 if (not_a_node(m)) continue;
335 useful.push(m);
336 }
337 }
338 }
339
340 // Update dead_node_list with any missing dead nodes using useful
341 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
342 void Compile::update_dead_node_list(Unique_Node_List &useful) {
343 uint max_idx = unique();
344 VectorSet& useful_node_set = useful.member_set();
345
346 for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
347 // If node with index node_idx is not in useful set,
348 // mark it as dead in dead node list.
349 if (! useful_node_set.test(node_idx) ) {
350 record_dead_node(node_idx);
351 }
352 }
353 }
354
355 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
356 int shift = 0;
357 for (int i = 0; i < inlines->length(); i++) {
358 CallGenerator* cg = inlines->at(i);
359 CallNode* call = cg->call_node();
360 if (shift > 0) {
361 inlines->at_put(i-shift, cg);
362 }
363 if (!useful.member(call)) {
364 shift++;
365 }
366 }
367 inlines->trunc_to(inlines->length()-shift);
368 }
369
370 // Disconnect all useless nodes by disconnecting those at the boundary.
371 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
372 uint next = 0;
373 while (next < useful.size()) {
374 Node *n = useful.at(next++);
375 if (n->is_SafePoint()) {
376 // We're done with a parsing phase. Replaced nodes are not valid
377 // beyond that point.
378 n->as_SafePoint()->delete_replaced_nodes();
379 }
380 // Use raw traversal of out edges since this code removes out edges
381 int max = n->outcnt();
382 for (int j = 0; j < max; ++j) {
383 Node* child = n->raw_out(j);
384 if (! useful.member(child)) {
385 assert(!child->is_top() || child != top(),
386 "If top is cached in Compile object it is in useful list");
387 // Only need to remove this out-edge to the useless node
388 n->raw_del_out(j);
389 --j;
390 --max;
391 }
392 }
393 if (n->outcnt() == 1 && n->has_special_unique_user()) {
394 record_for_igvn(n->unique_out());
395 }
396 }
397 // Remove useless macro and predicate opaq nodes
398 for (int i = C->macro_count()-1; i >= 0; i--) {
399 Node* n = C->macro_node(i);
400 if (!useful.member(n)) {
401 remove_macro_node(n);
402 }
403 }
404 // Remove useless expensive node
405 for (int i = C->expensive_count()-1; i >= 0; i--) {
406 Node* n = C->expensive_node(i);
407 if (!useful.member(n)) {
408 remove_expensive_node(n);
409 }
410 }
411 // clean up the late inline lists
412 remove_useless_late_inlines(&_string_late_inlines, useful);
413 remove_useless_late_inlines(&_boxing_late_inlines, useful);
414 remove_useless_late_inlines(&_late_inlines, useful);
415 debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
416 }
417
418 //------------------------------frame_size_in_words-----------------------------
419 // frame_slots in units of words
420 int Compile::frame_size_in_words() const {
421 // shift is 0 in LP32 and 1 in LP64
422 const int shift = (LogBytesPerWord - LogBytesPerInt);
423 int words = _frame_slots >> shift;
424 assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
425 return words;
426 }
427
428 // To bang the stack of this compiled method we use the stack size
429 // that the interpreter would need in case of a deoptimization. This
430 // removes the need to bang the stack in the deoptimization blob which
431 // in turn simplifies stack overflow handling.
432 int Compile::bang_size_in_bytes() const {
433 return MAX2(frame_size_in_bytes() + os::extra_bang_size_in_bytes(), _interpreter_frame_size);
434 }
435
436 // ============================================================================
437 //------------------------------CompileWrapper---------------------------------
438 class CompileWrapper : public StackObj {
439 Compile *const _compile;
440 public:
441 CompileWrapper(Compile* compile);
442
443 ~CompileWrapper();
444 };
445
446 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
447 // the Compile* pointer is stored in the current ciEnv:
448 ciEnv* env = compile->env();
449 assert(env == ciEnv::current(), "must already be a ciEnv active");
450 assert(env->compiler_data() == NULL, "compile already active?");
451 env->set_compiler_data(compile);
452 assert(compile == Compile::current(), "sanity");
453
454 compile->set_type_dict(NULL);
455 compile->set_type_hwm(NULL);
456 compile->set_type_last_size(0);
457 compile->set_last_tf(NULL, NULL);
458 compile->set_indexSet_arena(NULL);
459 compile->set_indexSet_free_block_list(NULL);
460 compile->init_type_arena();
461 Type::Initialize(compile);
462 _compile->set_scratch_buffer_blob(NULL);
463 _compile->begin_method();
464 }
465 CompileWrapper::~CompileWrapper() {
466 _compile->end_method();
467 if (_compile->scratch_buffer_blob() != NULL)
468 BufferBlob::free(_compile->scratch_buffer_blob());
469 _compile->env()->set_compiler_data(NULL);
470 }
471
472
473 //----------------------------print_compile_messages---------------------------
474 void Compile::print_compile_messages() {
475 #ifndef PRODUCT
476 // Check if recompiling
477 if (_subsume_loads == false && PrintOpto) {
478 // Recompiling without allowing machine instructions to subsume loads
479 tty->print_cr("*********************************************************");
480 tty->print_cr("** Bailout: Recompile without subsuming loads **");
481 tty->print_cr("*********************************************************");
482 }
483 if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
484 // Recompiling without escape analysis
485 tty->print_cr("*********************************************************");
486 tty->print_cr("** Bailout: Recompile without escape analysis **");
487 tty->print_cr("*********************************************************");
488 }
489 if (_eliminate_boxing != EliminateAutoBox && PrintOpto) {
490 // Recompiling without boxing elimination
491 tty->print_cr("*********************************************************");
492 tty->print_cr("** Bailout: Recompile without boxing elimination **");
493 tty->print_cr("*********************************************************");
494 }
495 if (env()->break_at_compile()) {
496 // Open the debugger when compiling this method.
497 tty->print("### Breaking when compiling: ");
498 method()->print_short_name();
499 tty->cr();
500 BREAKPOINT;
501 }
502
503 if( PrintOpto ) {
504 if (is_osr_compilation()) {
505 tty->print("[OSR]%3d", _compile_id);
506 } else {
507 tty->print("%3d", _compile_id);
508 }
509 }
510 #endif
511 }
512
513
514 //-----------------------init_scratch_buffer_blob------------------------------
515 // Construct a temporary BufferBlob and cache it for this compile.
516 void Compile::init_scratch_buffer_blob(int const_size) {
517 // If there is already a scratch buffer blob allocated and the
518 // constant section is big enough, use it. Otherwise free the
519 // current and allocate a new one.
520 BufferBlob* blob = scratch_buffer_blob();
521 if ((blob != NULL) && (const_size <= _scratch_const_size)) {
522 // Use the current blob.
523 } else {
524 if (blob != NULL) {
525 BufferBlob::free(blob);
526 }
527
528 ResourceMark rm;
529 _scratch_const_size = const_size;
530 int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
531 blob = BufferBlob::create("Compile::scratch_buffer", size);
532 // Record the buffer blob for next time.
533 set_scratch_buffer_blob(blob);
534 // Have we run out of code space?
535 if (scratch_buffer_blob() == NULL) {
536 // Let CompilerBroker disable further compilations.
537 record_failure("Not enough space for scratch buffer in CodeCache");
538 CompileBroker::handle_full_code_cache(CodeBlobType::NonNMethod);
539 return;
540 }
541 }
542
543 // Initialize the relocation buffers
544 relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
545 set_scratch_locs_memory(locs_buf);
546 }
547
548
549 //-----------------------scratch_emit_size-------------------------------------
550 // Helper function that computes size by emitting code
551 uint Compile::scratch_emit_size(const Node* n) {
552 // Start scratch_emit_size section.
553 set_in_scratch_emit_size(true);
554
555 // Emit into a trash buffer and count bytes emitted.
556 // This is a pretty expensive way to compute a size,
557 // but it works well enough if seldom used.
558 // All common fixed-size instructions are given a size
559 // method by the AD file.
560 // Note that the scratch buffer blob and locs memory are
561 // allocated at the beginning of the compile task, and
562 // may be shared by several calls to scratch_emit_size.
563 // The allocation of the scratch buffer blob is particularly
564 // expensive, since it has to grab the code cache lock.
565 BufferBlob* blob = this->scratch_buffer_blob();
566 assert(blob != NULL, "Initialize BufferBlob at start");
567 assert(blob->size() > MAX_inst_size, "sanity");
568 relocInfo* locs_buf = scratch_locs_memory();
569 address blob_begin = blob->content_begin();
570 address blob_end = (address)locs_buf;
571 assert(blob->content_contains(blob_end), "sanity");
572 CodeBuffer buf(blob_begin, blob_end - blob_begin);
573 buf.initialize_consts_size(_scratch_const_size);
574 buf.initialize_stubs_size(MAX_stubs_size);
575 assert(locs_buf != NULL, "sanity");
576 int lsize = MAX_locs_size / 3;
577 buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
578 buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
579 buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
580
581 // Do the emission.
582
583 Label fakeL; // Fake label for branch instructions.
584 Label* saveL = NULL;
585 uint save_bnum = 0;
586 bool is_branch = n->is_MachBranch();
587 if (is_branch) {
588 MacroAssembler masm(&buf);
589 masm.bind(fakeL);
590 n->as_MachBranch()->save_label(&saveL, &save_bnum);
591 n->as_MachBranch()->label_set(&fakeL, 0);
592 }
593 n->emit(buf, this->regalloc());
594 if (is_branch) // Restore label.
595 n->as_MachBranch()->label_set(saveL, save_bnum);
596
597 // End scratch_emit_size section.
598 set_in_scratch_emit_size(false);
599
600 return buf.insts_size();
601 }
602
603
604 // ============================================================================
605 //------------------------------Compile standard-------------------------------
606 debug_only( int Compile::_debug_idx = 100000; )
607
608 // Compile a method. entry_bci is -1 for normal compilations and indicates
609 // the continuation bci for on stack replacement.
610
611
612 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci,
613 bool subsume_loads, bool do_escape_analysis, bool eliminate_boxing )
614 : Phase(Compiler),
615 _env(ci_env),
616 _log(ci_env->log()),
617 _compile_id(ci_env->compile_id()),
618 _save_argument_registers(false),
619 _stub_name(NULL),
620 _stub_function(NULL),
621 _stub_entry_point(NULL),
622 _method(target),
623 _entry_bci(osr_bci),
624 _initial_gvn(NULL),
625 _for_igvn(NULL),
626 _warm_calls(NULL),
627 _subsume_loads(subsume_loads),
628 _do_escape_analysis(do_escape_analysis),
629 _eliminate_boxing(eliminate_boxing),
630 _failure_reason(NULL),
631 _code_buffer("Compile::Fill_buffer"),
632 _orig_pc_slot(0),
633 _orig_pc_slot_offset_in_bytes(0),
634 _has_method_handle_invokes(false),
635 _mach_constant_base_node(NULL),
636 _node_bundling_limit(0),
637 _node_bundling_base(NULL),
638 _java_calls(0),
639 _inner_loops(0),
640 _scratch_const_size(-1),
641 _in_scratch_emit_size(false),
642 _dead_node_list(comp_arena()),
643 _dead_node_count(0),
644 #ifndef PRODUCT
645 _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
646 _in_dump_cnt(0),
647 _printer(IdealGraphPrinter::printer()),
648 #endif
649 _congraph(NULL),
650 _comp_arena(mtCompiler),
651 _node_arena(mtCompiler),
652 _old_arena(mtCompiler),
653 _Compile_types(mtCompiler),
654 _replay_inline_data(NULL),
655 _late_inlines(comp_arena(), 2, 0, NULL),
656 _string_late_inlines(comp_arena(), 2, 0, NULL),
657 _boxing_late_inlines(comp_arena(), 2, 0, NULL),
658 _late_inlines_pos(0),
659 _number_of_mh_late_inlines(0),
660 _inlining_progress(false),
661 _inlining_incrementally(false),
662 _print_inlining_list(NULL),
663 _print_inlining_stream(NULL),
664 _print_inlining_idx(0),
665 _print_inlining_output(NULL),
666 _interpreter_frame_size(0) {
667 C = this;
668
669 CompileWrapper cw(this);
670
671 if (CITimeVerbose) {
672 tty->print(" ");
673 target->holder()->name()->print();
674 tty->print(".");
675 target->print_short_name();
676 tty->print(" ");
677 }
678 TraceTime t1("Total compilation time", &_t_totalCompilation, CITime, CITimeVerbose);
679 TraceTime t2(NULL, &_t_methodCompilation, CITime, false);
680
681 #ifndef PRODUCT
682 bool print_opto_assembly = PrintOptoAssembly || _method->has_option("PrintOptoAssembly");
683 if (!print_opto_assembly) {
684 bool print_assembly = (PrintAssembly || _method->should_print_assembly());
685 if (print_assembly && !Disassembler::can_decode()) {
686 tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
687 print_opto_assembly = true;
688 }
689 }
690 set_print_assembly(print_opto_assembly);
691 set_parsed_irreducible_loop(false);
692
693 if (method()->has_option("ReplayInline")) {
694 _replay_inline_data = ciReplay::load_inline_data(method(), entry_bci(), ci_env->comp_level());
695 }
696 #endif
697 set_print_inlining(PrintInlining || method()->has_option("PrintInlining") NOT_PRODUCT( || PrintOptoInlining));
698 set_print_intrinsics(PrintIntrinsics || method()->has_option("PrintIntrinsics"));
699 set_has_irreducible_loop(true); // conservative until build_loop_tree() reset it
700
701 if (ProfileTraps RTM_OPT_ONLY( || UseRTMLocking )) {
702 // Make sure the method being compiled gets its own MDO,
703 // so we can at least track the decompile_count().
704 // Need MDO to record RTM code generation state.
705 method()->ensure_method_data();
706 }
707
708 Init(::AliasLevel);
709
710
711 print_compile_messages();
712
713 _ilt = InlineTree::build_inline_tree_root();
714
715 // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
716 assert(num_alias_types() >= AliasIdxRaw, "");
717
718 #define MINIMUM_NODE_HASH 1023
719 // Node list that Iterative GVN will start with
720 Unique_Node_List for_igvn(comp_arena());
721 set_for_igvn(&for_igvn);
722
723 // GVN that will be run immediately on new nodes
724 uint estimated_size = method()->code_size()*4+64;
725 estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
726 PhaseGVN gvn(node_arena(), estimated_size);
727 set_initial_gvn(&gvn);
728
729 print_inlining_init();
730 { // Scope for timing the parser
731 TracePhase tp("parse", &timers[_t_parser]);
732
733 // Put top into the hash table ASAP.
734 initial_gvn()->transform_no_reclaim(top());
735
736 // Set up tf(), start(), and find a CallGenerator.
737 CallGenerator* cg = NULL;
738 if (is_osr_compilation()) {
739 const TypeTuple *domain = StartOSRNode::osr_domain();
740 const TypeTuple *range = TypeTuple::make_range(method()->signature());
741 init_tf(TypeFunc::make(domain, range));
742 StartNode* s = new StartOSRNode(root(), domain);
743 initial_gvn()->set_type_bottom(s);
744 init_start(s);
745 cg = CallGenerator::for_osr(method(), entry_bci());
746 } else {
747 // Normal case.
748 init_tf(TypeFunc::make(method()));
749 StartNode* s = new StartNode(root(), tf()->domain());
750 initial_gvn()->set_type_bottom(s);
751 init_start(s);
752 if (method()->intrinsic_id() == vmIntrinsics::_Reference_get && UseG1GC) {
753 // With java.lang.ref.reference.get() we must go through the
754 // intrinsic when G1 is enabled - even when get() is the root
755 // method of the compile - so that, if necessary, the value in
756 // the referent field of the reference object gets recorded by
757 // the pre-barrier code.
758 // Specifically, if G1 is enabled, the value in the referent
759 // field is recorded by the G1 SATB pre barrier. This will
760 // result in the referent being marked live and the reference
761 // object removed from the list of discovered references during
762 // reference processing.
763 cg = find_intrinsic(method(), false);
764 }
765 if (cg == NULL) {
766 float past_uses = method()->interpreter_invocation_count();
767 float expected_uses = past_uses;
768 cg = CallGenerator::for_inline(method(), expected_uses);
769 }
770 }
771 if (failing()) return;
772 if (cg == NULL) {
773 record_method_not_compilable_all_tiers("cannot parse method");
774 return;
775 }
776 JVMState* jvms = build_start_state(start(), tf());
777 if ((jvms = cg->generate(jvms)) == NULL) {
778 record_method_not_compilable("method parse failed");
779 return;
780 }
781 GraphKit kit(jvms);
782
783 if (!kit.stopped()) {
784 // Accept return values, and transfer control we know not where.
785 // This is done by a special, unique ReturnNode bound to root.
786 return_values(kit.jvms());
787 }
788
789 if (kit.has_exceptions()) {
790 // Any exceptions that escape from this call must be rethrown
791 // to whatever caller is dynamically above us on the stack.
792 // This is done by a special, unique RethrowNode bound to root.
793 rethrow_exceptions(kit.transfer_exceptions_into_jvms());
794 }
795
796 assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
797
798 if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
799 inline_string_calls(true);
800 }
801
802 if (failing()) return;
803
804 print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
805
806 // Remove clutter produced by parsing.
807 if (!failing()) {
808 ResourceMark rm;
809 PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
810 }
811 }
812
813 // Note: Large methods are capped off in do_one_bytecode().
814 if (failing()) return;
815
816 // After parsing, node notes are no longer automagic.
817 // They must be propagated by register_new_node_with_optimizer(),
818 // clone(), or the like.
819 set_default_node_notes(NULL);
820
821 for (;;) {
822 int successes = Inline_Warm();
823 if (failing()) return;
824 if (successes == 0) break;
825 }
826
827 // Drain the list.
828 Finish_Warm();
829 #ifndef PRODUCT
830 if (_printer) {
831 _printer->print_inlining(this);
832 }
833 #endif
834
835 if (failing()) return;
836 NOT_PRODUCT( verify_graph_edges(); )
837
838 // Now optimize
839 Optimize();
840 if (failing()) return;
841 NOT_PRODUCT( verify_graph_edges(); )
842
843 #ifndef PRODUCT
844 if (PrintIdeal) {
845 ttyLocker ttyl; // keep the following output all in one block
846 // This output goes directly to the tty, not the compiler log.
847 // To enable tools to match it up with the compilation activity,
848 // be sure to tag this tty output with the compile ID.
849 if (xtty != NULL) {
850 xtty->head("ideal compile_id='%d'%s", compile_id(),
851 is_osr_compilation() ? " compile_kind='osr'" :
852 "");
853 }
854 root()->dump(9999);
855 if (xtty != NULL) {
856 xtty->tail("ideal");
857 }
858 }
859 #endif
860
861 NOT_PRODUCT( verify_barriers(); )
862
863 // Dump compilation data to replay it.
864 if (method()->has_option("DumpReplay")) {
865 env()->dump_replay_data(_compile_id);
866 }
867 if (method()->has_option("DumpInline") && (ilt() != NULL)) {
868 env()->dump_inline_data(_compile_id);
869 }
870
871 // Now that we know the size of all the monitors we can add a fixed slot
872 // for the original deopt pc.
873
874 _orig_pc_slot = fixed_slots();
875 int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
876 set_fixed_slots(next_slot);
877
878 // Compute when to use implicit null checks. Used by matching trap based
879 // nodes and NullCheck optimization.
880 set_allowed_deopt_reasons();
881
882 // Now generate code
883 Code_Gen();
884 if (failing()) return;
885
886 // Check if we want to skip execution of all compiled code.
887 {
888 #ifndef PRODUCT
889 if (OptoNoExecute) {
890 record_method_not_compilable("+OptoNoExecute"); // Flag as failed
891 return;
892 }
893 #endif
894 TracePhase tp("install_code", &timers[_t_registerMethod]);
895
896 if (is_osr_compilation()) {
897 _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
898 _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
899 } else {
900 _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
901 _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
902 }
903
904 env()->register_method(_method, _entry_bci,
905 &_code_offsets,
906 _orig_pc_slot_offset_in_bytes,
907 code_buffer(),
908 frame_size_in_words(), _oop_map_set,
909 &_handler_table, &_inc_table,
910 compiler,
911 env()->comp_level(),
912 has_unsafe_access(),
913 SharedRuntime::is_wide_vector(max_vector_size()),
914 rtm_state()
915 );
916
917 if (log() != NULL) // Print code cache state into compiler log
918 log()->code_cache_state();
919 }
920 }
921
922 //------------------------------Compile----------------------------------------
923 // Compile a runtime stub
924 Compile::Compile( ciEnv* ci_env,
925 TypeFunc_generator generator,
926 address stub_function,
927 const char *stub_name,
928 int is_fancy_jump,
929 bool pass_tls,
930 bool save_arg_registers,
931 bool return_pc )
932 : Phase(Compiler),
933 _env(ci_env),
934 _log(ci_env->log()),
935 _compile_id(0),
936 _save_argument_registers(save_arg_registers),
937 _method(NULL),
938 _stub_name(stub_name),
939 _stub_function(stub_function),
940 _stub_entry_point(NULL),
941 _entry_bci(InvocationEntryBci),
942 _initial_gvn(NULL),
943 _for_igvn(NULL),
944 _warm_calls(NULL),
945 _orig_pc_slot(0),
946 _orig_pc_slot_offset_in_bytes(0),
947 _subsume_loads(true),
948 _do_escape_analysis(false),
949 _eliminate_boxing(false),
950 _failure_reason(NULL),
951 _code_buffer("Compile::Fill_buffer"),
952 _has_method_handle_invokes(false),
953 _mach_constant_base_node(NULL),
954 _node_bundling_limit(0),
955 _node_bundling_base(NULL),
956 _java_calls(0),
957 _inner_loops(0),
958 #ifndef PRODUCT
959 _trace_opto_output(TraceOptoOutput),
960 _in_dump_cnt(0),
961 _printer(NULL),
962 #endif
963 _comp_arena(mtCompiler),
964 _node_arena(mtCompiler),
965 _old_arena(mtCompiler),
966 _Compile_types(mtCompiler),
967 _dead_node_list(comp_arena()),
968 _dead_node_count(0),
969 _congraph(NULL),
970 _replay_inline_data(NULL),
971 _number_of_mh_late_inlines(0),
972 _inlining_progress(false),
973 _inlining_incrementally(false),
974 _print_inlining_list(NULL),
975 _print_inlining_stream(NULL),
976 _print_inlining_idx(0),
977 _print_inlining_output(NULL),
978 _allowed_reasons(0),
979 _interpreter_frame_size(0) {
980 C = this;
981
982 TraceTime t1(NULL, &_t_totalCompilation, CITime, false);
983 TraceTime t2(NULL, &_t_stubCompilation, CITime, false);
984
985 #ifndef PRODUCT
986 set_print_assembly(PrintFrameConverterAssembly);
987 set_parsed_irreducible_loop(false);
988 #endif
989 set_has_irreducible_loop(false); // no loops
990
991 CompileWrapper cw(this);
992 Init(/*AliasLevel=*/ 0);
993 init_tf((*generator)());
994
995 {
996 // The following is a dummy for the sake of GraphKit::gen_stub
997 Unique_Node_List for_igvn(comp_arena());
998 set_for_igvn(&for_igvn); // not used, but some GraphKit guys push on this
999 PhaseGVN gvn(Thread::current()->resource_area(),255);
1000 set_initial_gvn(&gvn); // not significant, but GraphKit guys use it pervasively
1001 gvn.transform_no_reclaim(top());
1002
1003 GraphKit kit;
1004 kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
1005 }
1006
1007 NOT_PRODUCT( verify_graph_edges(); )
1008 Code_Gen();
1009 if (failing()) return;
1010
1011
1012 // Entry point will be accessed using compile->stub_entry_point();
1013 if (code_buffer() == NULL) {
1014 Matcher::soft_match_failure();
1015 } else {
1016 if (PrintAssembly && (WizardMode || Verbose))
1017 tty->print_cr("### Stub::%s", stub_name);
1018
1019 if (!failing()) {
1020 assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
1021
1022 // Make the NMethod
1023 // For now we mark the frame as never safe for profile stackwalking
1024 RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
1025 code_buffer(),
1026 CodeOffsets::frame_never_safe,
1027 // _code_offsets.value(CodeOffsets::Frame_Complete),
1028 frame_size_in_words(),
1029 _oop_map_set,
1030 save_arg_registers);
1031 assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
1032
1033 _stub_entry_point = rs->entry_point();
1034 }
1035 }
1036 }
1037
1038 //------------------------------Init-------------------------------------------
1039 // Prepare for a single compilation
1040 void Compile::Init(int aliaslevel) {
1041 _unique = 0;
1042 _regalloc = NULL;
1043
1044 _tf = NULL; // filled in later
1045 _top = NULL; // cached later
1046 _matcher = NULL; // filled in later
1047 _cfg = NULL; // filled in later
1048
1049 set_24_bit_selection_and_mode(Use24BitFP, false);
1050
1051 _node_note_array = NULL;
1052 _default_node_notes = NULL;
1053 DEBUG_ONLY( _modified_nodes = NULL; ) // Used in Optimize()
1054
1055 _immutable_memory = NULL; // filled in at first inquiry
1056
1057 // Globally visible Nodes
1058 // First set TOP to NULL to give safe behavior during creation of RootNode
1059 set_cached_top_node(NULL);
1060 set_root(new RootNode());
1061 // Now that you have a Root to point to, create the real TOP
1062 set_cached_top_node( new ConNode(Type::TOP) );
1063 set_recent_alloc(NULL, NULL);
1064
1065 // Create Debug Information Recorder to record scopes, oopmaps, etc.
1066 env()->set_oop_recorder(new OopRecorder(env()->arena()));
1067 env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
1068 env()->set_dependencies(new Dependencies(env()));
1069
1070 _fixed_slots = 0;
1071 set_has_split_ifs(false);
1072 set_has_loops(has_method() && method()->has_loops()); // first approximation
1073 set_has_stringbuilder(false);
1074 set_has_boxed_value(false);
1075 _trap_can_recompile = false; // no traps emitted yet
1076 _major_progress = true; // start out assuming good things will happen
1077 set_has_unsafe_access(false);
1078 set_max_vector_size(0);
1079 Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
1080 set_decompile_count(0);
1081
1082 set_do_freq_based_layout(BlockLayoutByFrequency || method_has_option("BlockLayoutByFrequency"));
1083 set_num_loop_opts(LoopOptsCount);
1084 set_do_inlining(Inline);
1085 set_max_inline_size(MaxInlineSize);
1086 set_freq_inline_size(FreqInlineSize);
1087 set_do_scheduling(OptoScheduling);
1088 set_do_count_invocations(false);
1089 set_do_method_data_update(false);
1090 set_age_code(has_method() && method()->profile_aging());
1091 set_rtm_state(NoRTM); // No RTM lock eliding by default
1092 #if INCLUDE_RTM_OPT
1093 if (UseRTMLocking && has_method() && (method()->method_data_or_null() != NULL)) {
1094 int rtm_state = method()->method_data()->rtm_state();
1095 if (method_has_option("NoRTMLockEliding") || ((rtm_state & NoRTM) != 0)) {
1096 // Don't generate RTM lock eliding code.
1097 set_rtm_state(NoRTM);
1098 } else if (method_has_option("UseRTMLockEliding") || ((rtm_state & UseRTM) != 0) || !UseRTMDeopt) {
1099 // Generate RTM lock eliding code without abort ratio calculation code.
1100 set_rtm_state(UseRTM);
1101 } else if (UseRTMDeopt) {
1102 // Generate RTM lock eliding code and include abort ratio calculation
1103 // code if UseRTMDeopt is on.
1104 set_rtm_state(ProfileRTM);
1105 }
1106 }
1107 #endif
1108 if (debug_info()->recording_non_safepoints()) {
1109 set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
1110 (comp_arena(), 8, 0, NULL));
1111 set_default_node_notes(Node_Notes::make(this));
1112 }
1113
1114 // // -- Initialize types before each compile --
1115 // // Update cached type information
1116 // if( _method && _method->constants() )
1117 // Type::update_loaded_types(_method, _method->constants());
1118
1119 // Init alias_type map.
1120 if (!_do_escape_analysis && aliaslevel == 3)
1121 aliaslevel = 2; // No unique types without escape analysis
1122 _AliasLevel = aliaslevel;
1123 const int grow_ats = 16;
1124 _max_alias_types = grow_ats;
1125 _alias_types = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
1126 AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType, grow_ats);
1127 Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
1128 {
1129 for (int i = 0; i < grow_ats; i++) _alias_types[i] = &ats[i];
1130 }
1131 // Initialize the first few types.
1132 _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
1133 _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1134 _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1135 _num_alias_types = AliasIdxRaw+1;
1136 // Zero out the alias type cache.
1137 Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1138 // A NULL adr_type hits in the cache right away. Preload the right answer.
1139 probe_alias_cache(NULL)->_index = AliasIdxTop;
1140
1141 _intrinsics = NULL;
1142 _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1143 _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1144 _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1145 register_library_intrinsics();
1146 }
1147
1148 //---------------------------init_start----------------------------------------
1149 // Install the StartNode on this compile object.
1150 void Compile::init_start(StartNode* s) {
1151 if (failing())
1152 return; // already failing
1153 assert(s == start(), "");
1154 }
1155
1156 /**
1157 * Return the 'StartNode'. We must not have a pending failure, since the ideal graph
1158 * can be in an inconsistent state, i.e., we can get segmentation faults when traversing
1159 * the ideal graph.
1160 */
1161 StartNode* Compile::start() const {
1162 assert (!failing(), err_msg_res("Must not have pending failure. Reason is: %s", failure_reason()));
1163 for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1164 Node* start = root()->fast_out(i);
1165 if (start->is_Start()) {
1166 return start->as_Start();
1167 }
1168 }
1169 fatal("Did not find Start node!");
1170 return NULL;
1171 }
1172
1173 //-------------------------------immutable_memory-------------------------------------
1174 // Access immutable memory
1175 Node* Compile::immutable_memory() {
1176 if (_immutable_memory != NULL) {
1177 return _immutable_memory;
1178 }
1179 StartNode* s = start();
1180 for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1181 Node *p = s->fast_out(i);
1182 if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1183 _immutable_memory = p;
1184 return _immutable_memory;
1185 }
1186 }
1187 ShouldNotReachHere();
1188 return NULL;
1189 }
1190
1191 //----------------------set_cached_top_node------------------------------------
1192 // Install the cached top node, and make sure Node::is_top works correctly.
1193 void Compile::set_cached_top_node(Node* tn) {
1194 if (tn != NULL) verify_top(tn);
1195 Node* old_top = _top;
1196 _top = tn;
1197 // Calling Node::setup_is_top allows the nodes the chance to adjust
1198 // their _out arrays.
1199 if (_top != NULL) _top->setup_is_top();
1200 if (old_top != NULL) old_top->setup_is_top();
1201 assert(_top == NULL || top()->is_top(), "");
1202 }
1203
1204 #ifdef ASSERT
1205 uint Compile::count_live_nodes_by_graph_walk() {
1206 Unique_Node_List useful(comp_arena());
1207 // Get useful node list by walking the graph.
1208 identify_useful_nodes(useful);
1209 return useful.size();
1210 }
1211
1212 void Compile::print_missing_nodes() {
1213
1214 // Return if CompileLog is NULL and PrintIdealNodeCount is false.
1215 if ((_log == NULL) && (! PrintIdealNodeCount)) {
1216 return;
1217 }
1218
1219 // This is an expensive function. It is executed only when the user
1220 // specifies VerifyIdealNodeCount option or otherwise knows the
1221 // additional work that needs to be done to identify reachable nodes
1222 // by walking the flow graph and find the missing ones using
1223 // _dead_node_list.
1224
1225 Unique_Node_List useful(comp_arena());
1226 // Get useful node list by walking the graph.
1227 identify_useful_nodes(useful);
1228
1229 uint l_nodes = C->live_nodes();
1230 uint l_nodes_by_walk = useful.size();
1231
1232 if (l_nodes != l_nodes_by_walk) {
1233 if (_log != NULL) {
1234 _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
1235 _log->stamp();
1236 _log->end_head();
1237 }
1238 VectorSet& useful_member_set = useful.member_set();
1239 int last_idx = l_nodes_by_walk;
1240 for (int i = 0; i < last_idx; i++) {
1241 if (useful_member_set.test(i)) {
1242 if (_dead_node_list.test(i)) {
1243 if (_log != NULL) {
1244 _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
1245 }
1246 if (PrintIdealNodeCount) {
1247 // Print the log message to tty
1248 tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
1249 useful.at(i)->dump();
1250 }
1251 }
1252 }
1253 else if (! _dead_node_list.test(i)) {
1254 if (_log != NULL) {
1255 _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
1256 }
1257 if (PrintIdealNodeCount) {
1258 // Print the log message to tty
1259 tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
1260 }
1261 }
1262 }
1263 if (_log != NULL) {
1264 _log->tail("mismatched_nodes");
1265 }
1266 }
1267 }
1268 void Compile::record_modified_node(Node* n) {
1269 if (_modified_nodes != NULL && !_inlining_incrementally &&
1270 n->outcnt() != 0 && !n->is_Con()) {
1271 _modified_nodes->push(n);
1272 }
1273 }
1274
1275 void Compile::remove_modified_node(Node* n) {
1276 if (_modified_nodes != NULL) {
1277 _modified_nodes->remove(n);
1278 }
1279 }
1280 #endif
1281
1282 #ifndef PRODUCT
1283 void Compile::verify_top(Node* tn) const {
1284 if (tn != NULL) {
1285 assert(tn->is_Con(), "top node must be a constant");
1286 assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1287 assert(tn->in(0) != NULL, "must have live top node");
1288 }
1289 }
1290 #endif
1291
1292
1293 ///-------------------Managing Per-Node Debug & Profile Info-------------------
1294
1295 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1296 guarantee(arr != NULL, "");
1297 int num_blocks = arr->length();
1298 if (grow_by < num_blocks) grow_by = num_blocks;
1299 int num_notes = grow_by * _node_notes_block_size;
1300 Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1301 Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1302 while (num_notes > 0) {
1303 arr->append(notes);
1304 notes += _node_notes_block_size;
1305 num_notes -= _node_notes_block_size;
1306 }
1307 assert(num_notes == 0, "exact multiple, please");
1308 }
1309
1310 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1311 if (source == NULL || dest == NULL) return false;
1312
1313 if (dest->is_Con())
1314 return false; // Do not push debug info onto constants.
1315
1316 #ifdef ASSERT
1317 // Leave a bread crumb trail pointing to the original node:
1318 if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
1319 dest->set_debug_orig(source);
1320 }
1321 #endif
1322
1323 if (node_note_array() == NULL)
1324 return false; // Not collecting any notes now.
1325
1326 // This is a copy onto a pre-existing node, which may already have notes.
1327 // If both nodes have notes, do not overwrite any pre-existing notes.
1328 Node_Notes* source_notes = node_notes_at(source->_idx);
1329 if (source_notes == NULL || source_notes->is_clear()) return false;
1330 Node_Notes* dest_notes = node_notes_at(dest->_idx);
1331 if (dest_notes == NULL || dest_notes->is_clear()) {
1332 return set_node_notes_at(dest->_idx, source_notes);
1333 }
1334
1335 Node_Notes merged_notes = (*source_notes);
1336 // The order of operations here ensures that dest notes will win...
1337 merged_notes.update_from(dest_notes);
1338 return set_node_notes_at(dest->_idx, &merged_notes);
1339 }
1340
1341
1342 //--------------------------allow_range_check_smearing-------------------------
1343 // Gating condition for coalescing similar range checks.
1344 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1345 // single covering check that is at least as strong as any of them.
1346 // If the optimization succeeds, the simplified (strengthened) range check
1347 // will always succeed. If it fails, we will deopt, and then give up
1348 // on the optimization.
1349 bool Compile::allow_range_check_smearing() const {
1350 // If this method has already thrown a range-check,
1351 // assume it was because we already tried range smearing
1352 // and it failed.
1353 uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1354 return !already_trapped;
1355 }
1356
1357
1358 //------------------------------flatten_alias_type-----------------------------
1359 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1360 int offset = tj->offset();
1361 TypePtr::PTR ptr = tj->ptr();
1362
1363 // Known instance (scalarizable allocation) alias only with itself.
1364 bool is_known_inst = tj->isa_oopptr() != NULL &&
1365 tj->is_oopptr()->is_known_instance();
1366
1367 // Process weird unsafe references.
1368 if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1369 assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
1370 assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1371 tj = TypeOopPtr::BOTTOM;
1372 ptr = tj->ptr();
1373 offset = tj->offset();
1374 }
1375
1376 // Array pointers need some flattening
1377 const TypeAryPtr *ta = tj->isa_aryptr();
1378 if (ta && ta->is_stable()) {
1379 // Erase stability property for alias analysis.
1380 tj = ta = ta->cast_to_stable(false);
1381 }
1382 if( ta && is_known_inst ) {
1383 if ( offset != Type::OffsetBot &&
1384 offset > arrayOopDesc::length_offset_in_bytes() ) {
1385 offset = Type::OffsetBot; // Flatten constant access into array body only
1386 tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
1387 }
1388 } else if( ta && _AliasLevel >= 2 ) {
1389 // For arrays indexed by constant indices, we flatten the alias
1390 // space to include all of the array body. Only the header, klass
1391 // and array length can be accessed un-aliased.
1392 if( offset != Type::OffsetBot ) {
1393 if( ta->const_oop() ) { // MethodData* or Method*
1394 offset = Type::OffsetBot; // Flatten constant access into array body
1395 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
1396 } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1397 // range is OK as-is.
1398 tj = ta = TypeAryPtr::RANGE;
1399 } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1400 tj = TypeInstPtr::KLASS; // all klass loads look alike
1401 ta = TypeAryPtr::RANGE; // generic ignored junk
1402 ptr = TypePtr::BotPTR;
1403 } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1404 tj = TypeInstPtr::MARK;
1405 ta = TypeAryPtr::RANGE; // generic ignored junk
1406 ptr = TypePtr::BotPTR;
1407 } else { // Random constant offset into array body
1408 offset = Type::OffsetBot; // Flatten constant access into array body
1409 tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
1410 }
1411 }
1412 // Arrays of fixed size alias with arrays of unknown size.
1413 if (ta->size() != TypeInt::POS) {
1414 const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1415 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
1416 }
1417 // Arrays of known objects become arrays of unknown objects.
1418 if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1419 const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1420 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1421 }
1422 if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1423 const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1424 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1425 }
1426 // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1427 // cannot be distinguished by bytecode alone.
1428 if (ta->elem() == TypeInt::BOOL) {
1429 const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1430 ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1431 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
1432 }
1433 // During the 2nd round of IterGVN, NotNull castings are removed.
1434 // Make sure the Bottom and NotNull variants alias the same.
1435 // Also, make sure exact and non-exact variants alias the same.
1436 if (ptr == TypePtr::NotNull || ta->klass_is_exact() || ta->speculative() != NULL) {
1437 tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
1438 }
1439 }
1440
1441 // Oop pointers need some flattening
1442 const TypeInstPtr *to = tj->isa_instptr();
1443 if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
1444 ciInstanceKlass *k = to->klass()->as_instance_klass();
1445 if( ptr == TypePtr::Constant ) {
1446 if (to->klass() != ciEnv::current()->Class_klass() ||
1447 offset < k->size_helper() * wordSize) {
1448 // No constant oop pointers (such as Strings); they alias with
1449 // unknown strings.
1450 assert(!is_known_inst, "not scalarizable allocation");
1451 tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1452 }
1453 } else if( is_known_inst ) {
1454 tj = to; // Keep NotNull and klass_is_exact for instance type
1455 } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1456 // During the 2nd round of IterGVN, NotNull castings are removed.
1457 // Make sure the Bottom and NotNull variants alias the same.
1458 // Also, make sure exact and non-exact variants alias the same.
1459 tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1460 }
1461 if (to->speculative() != NULL) {
1462 tj = to = TypeInstPtr::make(to->ptr(),to->klass(),to->klass_is_exact(),to->const_oop(),to->offset(), to->instance_id());
1463 }
1464 // Canonicalize the holder of this field
1465 if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1466 // First handle header references such as a LoadKlassNode, even if the
1467 // object's klass is unloaded at compile time (4965979).
1468 if (!is_known_inst) { // Do it only for non-instance types
1469 tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
1470 }
1471 } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
1472 // Static fields are in the space above the normal instance
1473 // fields in the java.lang.Class instance.
1474 if (to->klass() != ciEnv::current()->Class_klass()) {
1475 to = NULL;
1476 tj = TypeOopPtr::BOTTOM;
1477 offset = tj->offset();
1478 }
1479 } else {
1480 ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
1481 if (!k->equals(canonical_holder) || tj->offset() != offset) {
1482 if( is_known_inst ) {
1483 tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
1484 } else {
1485 tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
1486 }
1487 }
1488 }
1489 }
1490
1491 // Klass pointers to object array klasses need some flattening
1492 const TypeKlassPtr *tk = tj->isa_klassptr();
1493 if( tk ) {
1494 // If we are referencing a field within a Klass, we need
1495 // to assume the worst case of an Object. Both exact and
1496 // inexact types must flatten to the same alias class so
1497 // use NotNull as the PTR.
1498 if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1499
1500 tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
1501 TypeKlassPtr::OBJECT->klass(),
1502 offset);
1503 }
1504
1505 ciKlass* klass = tk->klass();
1506 if( klass->is_obj_array_klass() ) {
1507 ciKlass* k = TypeAryPtr::OOPS->klass();
1508 if( !k || !k->is_loaded() ) // Only fails for some -Xcomp runs
1509 k = TypeInstPtr::BOTTOM->klass();
1510 tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
1511 }
1512
1513 // Check for precise loads from the primary supertype array and force them
1514 // to the supertype cache alias index. Check for generic array loads from
1515 // the primary supertype array and also force them to the supertype cache
1516 // alias index. Since the same load can reach both, we need to merge
1517 // these 2 disparate memories into the same alias class. Since the
1518 // primary supertype array is read-only, there's no chance of confusion
1519 // where we bypass an array load and an array store.
1520 int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
1521 if (offset == Type::OffsetBot ||
1522 (offset >= primary_supers_offset &&
1523 offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
1524 offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
1525 offset = in_bytes(Klass::secondary_super_cache_offset());
1526 tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
1527 }
1528 }
1529
1530 // Flatten all Raw pointers together.
1531 if (tj->base() == Type::RawPtr)
1532 tj = TypeRawPtr::BOTTOM;
1533
1534 if (tj->base() == Type::AnyPtr)
1535 tj = TypePtr::BOTTOM; // An error, which the caller must check for.
1536
1537 // Flatten all to bottom for now
1538 switch( _AliasLevel ) {
1539 case 0:
1540 tj = TypePtr::BOTTOM;
1541 break;
1542 case 1: // Flatten to: oop, static, field or array
1543 switch (tj->base()) {
1544 //case Type::AryPtr: tj = TypeAryPtr::RANGE; break;
1545 case Type::RawPtr: tj = TypeRawPtr::BOTTOM; break;
1546 case Type::AryPtr: // do not distinguish arrays at all
1547 case Type::InstPtr: tj = TypeInstPtr::BOTTOM; break;
1548 case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
1549 case Type::AnyPtr: tj = TypePtr::BOTTOM; break; // caller checks it
1550 default: ShouldNotReachHere();
1551 }
1552 break;
1553 case 2: // No collapsing at level 2; keep all splits
1554 case 3: // No collapsing at level 3; keep all splits
1555 break;
1556 default:
1557 Unimplemented();
1558 }
1559
1560 offset = tj->offset();
1561 assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1562
1563 assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1564 (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1565 (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1566 (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1567 (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1568 (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1569 (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr) ,
1570 "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1571 assert( tj->ptr() != TypePtr::TopPTR &&
1572 tj->ptr() != TypePtr::AnyNull &&
1573 tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1574 // assert( tj->ptr() != TypePtr::Constant ||
1575 // tj->base() == Type::RawPtr ||
1576 // tj->base() == Type::KlassPtr, "No constant oop addresses" );
1577
1578 return tj;
1579 }
1580
1581 void Compile::AliasType::Init(int i, const TypePtr* at) {
1582 _index = i;
1583 _adr_type = at;
1584 _field = NULL;
1585 _element = NULL;
1586 _is_rewritable = true; // default
1587 const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
1588 if (atoop != NULL && atoop->is_known_instance()) {
1589 const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1590 _general_index = Compile::current()->get_alias_index(gt);
1591 } else {
1592 _general_index = 0;
1593 }
1594 }
1595
1596 //---------------------------------print_on------------------------------------
1597 #ifndef PRODUCT
1598 void Compile::AliasType::print_on(outputStream* st) {
1599 if (index() < 10)
1600 st->print("@ <%d> ", index());
1601 else st->print("@ <%d>", index());
1602 st->print(is_rewritable() ? " " : " RO");
1603 int offset = adr_type()->offset();
1604 if (offset == Type::OffsetBot)
1605 st->print(" +any");
1606 else st->print(" +%-3d", offset);
1607 st->print(" in ");
1608 adr_type()->dump_on(st);
1609 const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1610 if (field() != NULL && tjp) {
1611 if (tjp->klass() != field()->holder() ||
1612 tjp->offset() != field()->offset_in_bytes()) {
1613 st->print(" != ");
1614 field()->print();
1615 st->print(" ***");
1616 }
1617 }
1618 }
1619
1620 void print_alias_types() {
1621 Compile* C = Compile::current();
1622 tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1623 for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1624 C->alias_type(idx)->print_on(tty);
1625 tty->cr();
1626 }
1627 }
1628 #endif
1629
1630
1631 //----------------------------probe_alias_cache--------------------------------
1632 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1633 intptr_t key = (intptr_t) adr_type;
1634 key ^= key >> logAliasCacheSize;
1635 return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1636 }
1637
1638
1639 //-----------------------------grow_alias_types--------------------------------
1640 void Compile::grow_alias_types() {
1641 const int old_ats = _max_alias_types; // how many before?
1642 const int new_ats = old_ats; // how many more?
1643 const int grow_ats = old_ats+new_ats; // how many now?
1644 _max_alias_types = grow_ats;
1645 _alias_types = REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1646 AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1647 Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1648 for (int i = 0; i < new_ats; i++) _alias_types[old_ats+i] = &ats[i];
1649 }
1650
1651
1652 //--------------------------------find_alias_type------------------------------
1653 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1654 if (_AliasLevel == 0)
1655 return alias_type(AliasIdxBot);
1656
1657 AliasCacheEntry* ace = probe_alias_cache(adr_type);
1658 if (ace->_adr_type == adr_type) {
1659 return alias_type(ace->_index);
1660 }
1661
1662 // Handle special cases.
1663 if (adr_type == NULL) return alias_type(AliasIdxTop);
1664 if (adr_type == TypePtr::BOTTOM) return alias_type(AliasIdxBot);
1665
1666 // Do it the slow way.
1667 const TypePtr* flat = flatten_alias_type(adr_type);
1668
1669 #ifdef ASSERT
1670 assert(flat == flatten_alias_type(flat), "idempotent");
1671 assert(flat != TypePtr::BOTTOM, "cannot alias-analyze an untyped ptr");
1672 if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1673 const TypeOopPtr* foop = flat->is_oopptr();
1674 // Scalarizable allocations have exact klass always.
1675 bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1676 const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1677 assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type");
1678 }
1679 assert(flat == flatten_alias_type(flat), "exact bit doesn't matter");
1680 #endif
1681
1682 int idx = AliasIdxTop;
1683 for (int i = 0; i < num_alias_types(); i++) {
1684 if (alias_type(i)->adr_type() == flat) {
1685 idx = i;
1686 break;
1687 }
1688 }
1689
1690 if (idx == AliasIdxTop) {
1691 if (no_create) return NULL;
1692 // Grow the array if necessary.
1693 if (_num_alias_types == _max_alias_types) grow_alias_types();
1694 // Add a new alias type.
1695 idx = _num_alias_types++;
1696 _alias_types[idx]->Init(idx, flat);
1697 if (flat == TypeInstPtr::KLASS) alias_type(idx)->set_rewritable(false);
1698 if (flat == TypeAryPtr::RANGE) alias_type(idx)->set_rewritable(false);
1699 if (flat->isa_instptr()) {
1700 if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
1701 && flat->is_instptr()->klass() == env()->Class_klass())
1702 alias_type(idx)->set_rewritable(false);
1703 }
1704 if (flat->isa_aryptr()) {
1705 #ifdef ASSERT
1706 const int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1707 // (T_BYTE has the weakest alignment and size restrictions...)
1708 assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
1709 #endif
1710 if (flat->offset() == TypePtr::OffsetBot) {
1711 alias_type(idx)->set_element(flat->is_aryptr()->elem());
1712 }
1713 }
1714 if (flat->isa_klassptr()) {
1715 if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
1716 alias_type(idx)->set_rewritable(false);
1717 if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
1718 alias_type(idx)->set_rewritable(false);
1719 if (flat->offset() == in_bytes(Klass::access_flags_offset()))
1720 alias_type(idx)->set_rewritable(false);
1721 if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
1722 alias_type(idx)->set_rewritable(false);
1723 }
1724 // %%% (We would like to finalize JavaThread::threadObj_offset(),
1725 // but the base pointer type is not distinctive enough to identify
1726 // references into JavaThread.)
1727
1728 // Check for final fields.
1729 const TypeInstPtr* tinst = flat->isa_instptr();
1730 if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1731 ciField* field;
1732 if (tinst->const_oop() != NULL &&
1733 tinst->klass() == ciEnv::current()->Class_klass() &&
1734 tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
1735 // static field
1736 ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1737 field = k->get_field_by_offset(tinst->offset(), true);
1738 } else {
1739 ciInstanceKlass *k = tinst->klass()->as_instance_klass();
1740 field = k->get_field_by_offset(tinst->offset(), false);
1741 }
1742 assert(field == NULL ||
1743 original_field == NULL ||
1744 (field->holder() == original_field->holder() &&
1745 field->offset() == original_field->offset() &&
1746 field->is_static() == original_field->is_static()), "wrong field?");
1747 // Set field() and is_rewritable() attributes.
1748 if (field != NULL) alias_type(idx)->set_field(field);
1749 }
1750 }
1751
1752 // Fill the cache for next time.
1753 ace->_adr_type = adr_type;
1754 ace->_index = idx;
1755 assert(alias_type(adr_type) == alias_type(idx), "type must be installed");
1756
1757 // Might as well try to fill the cache for the flattened version, too.
1758 AliasCacheEntry* face = probe_alias_cache(flat);
1759 if (face->_adr_type == NULL) {
1760 face->_adr_type = flat;
1761 face->_index = idx;
1762 assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1763 }
1764
1765 return alias_type(idx);
1766 }
1767
1768
1769 Compile::AliasType* Compile::alias_type(ciField* field) {
1770 const TypeOopPtr* t;
1771 if (field->is_static())
1772 t = TypeInstPtr::make(field->holder()->java_mirror());
1773 else
1774 t = TypeOopPtr::make_from_klass_raw(field->holder());
1775 AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1776 assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
1777 return atp;
1778 }
1779
1780
1781 //------------------------------have_alias_type--------------------------------
1782 bool Compile::have_alias_type(const TypePtr* adr_type) {
1783 AliasCacheEntry* ace = probe_alias_cache(adr_type);
1784 if (ace->_adr_type == adr_type) {
1785 return true;
1786 }
1787
1788 // Handle special cases.
1789 if (adr_type == NULL) return true;
1790 if (adr_type == TypePtr::BOTTOM) return true;
1791
1792 return find_alias_type(adr_type, true, NULL) != NULL;
1793 }
1794
1795 //-----------------------------must_alias--------------------------------------
1796 // True if all values of the given address type are in the given alias category.
1797 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1798 if (alias_idx == AliasIdxBot) return true; // the universal category
1799 if (adr_type == NULL) return true; // NULL serves as TypePtr::TOP
1800 if (alias_idx == AliasIdxTop) return false; // the empty category
1801 if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1802
1803 // the only remaining possible overlap is identity
1804 int adr_idx = get_alias_index(adr_type);
1805 assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1806 assert(adr_idx == alias_idx ||
1807 (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1808 && adr_type != TypeOopPtr::BOTTOM),
1809 "should not be testing for overlap with an unsafe pointer");
1810 return adr_idx == alias_idx;
1811 }
1812
1813 //------------------------------can_alias--------------------------------------
1814 // True if any values of the given address type are in the given alias category.
1815 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1816 if (alias_idx == AliasIdxTop) return false; // the empty category
1817 if (adr_type == NULL) return false; // NULL serves as TypePtr::TOP
1818 if (alias_idx == AliasIdxBot) return true; // the universal category
1819 if (adr_type->base() == Type::AnyPtr) return true; // TypePtr::BOTTOM or its twins
1820
1821 // the only remaining possible overlap is identity
1822 int adr_idx = get_alias_index(adr_type);
1823 assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1824 return adr_idx == alias_idx;
1825 }
1826
1827
1828
1829 //---------------------------pop_warm_call-------------------------------------
1830 WarmCallInfo* Compile::pop_warm_call() {
1831 WarmCallInfo* wci = _warm_calls;
1832 if (wci != NULL) _warm_calls = wci->remove_from(wci);
1833 return wci;
1834 }
1835
1836 //----------------------------Inline_Warm--------------------------------------
1837 int Compile::Inline_Warm() {
1838 // If there is room, try to inline some more warm call sites.
1839 // %%% Do a graph index compaction pass when we think we're out of space?
1840 if (!InlineWarmCalls) return 0;
1841
1842 int calls_made_hot = 0;
1843 int room_to_grow = NodeCountInliningCutoff - unique();
1844 int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
1845 int amount_grown = 0;
1846 WarmCallInfo* call;
1847 while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
1848 int est_size = (int)call->size();
1849 if (est_size > (room_to_grow - amount_grown)) {
1850 // This one won't fit anyway. Get rid of it.
1851 call->make_cold();
1852 continue;
1853 }
1854 call->make_hot();
1855 calls_made_hot++;
1856 amount_grown += est_size;
1857 amount_to_grow -= est_size;
1858 }
1859
1860 if (calls_made_hot > 0) set_major_progress();
1861 return calls_made_hot;
1862 }
1863
1864
1865 //----------------------------Finish_Warm--------------------------------------
1866 void Compile::Finish_Warm() {
1867 if (!InlineWarmCalls) return;
1868 if (failing()) return;
1869 if (warm_calls() == NULL) return;
1870
1871 // Clean up loose ends, if we are out of space for inlining.
1872 WarmCallInfo* call;
1873 while ((call = pop_warm_call()) != NULL) {
1874 call->make_cold();
1875 }
1876 }
1877
1878 //---------------------cleanup_loop_predicates-----------------------
1879 // Remove the opaque nodes that protect the predicates so that all unused
1880 // checks and uncommon_traps will be eliminated from the ideal graph
1881 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
1882 if (predicate_count()==0) return;
1883 for (int i = predicate_count(); i > 0; i--) {
1884 Node * n = predicate_opaque1_node(i-1);
1885 assert(n->Opcode() == Op_Opaque1, "must be");
1886 igvn.replace_node(n, n->in(1));
1887 }
1888 assert(predicate_count()==0, "should be clean!");
1889 }
1890
1891 // StringOpts and late inlining of string methods
1892 void Compile::inline_string_calls(bool parse_time) {
1893 {
1894 // remove useless nodes to make the usage analysis simpler
1895 ResourceMark rm;
1896 PhaseRemoveUseless pru(initial_gvn(), for_igvn());
1897 }
1898
1899 {
1900 ResourceMark rm;
1901 print_method(PHASE_BEFORE_STRINGOPTS, 3);
1902 PhaseStringOpts pso(initial_gvn(), for_igvn());
1903 print_method(PHASE_AFTER_STRINGOPTS, 3);
1904 }
1905
1906 // now inline anything that we skipped the first time around
1907 if (!parse_time) {
1908 _late_inlines_pos = _late_inlines.length();
1909 }
1910
1911 while (_string_late_inlines.length() > 0) {
1912 CallGenerator* cg = _string_late_inlines.pop();
1913 cg->do_late_inline();
1914 if (failing()) return;
1915 }
1916 _string_late_inlines.trunc_to(0);
1917 }
1918
1919 // Late inlining of boxing methods
1920 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
1921 if (_boxing_late_inlines.length() > 0) {
1922 assert(has_boxed_value(), "inconsistent");
1923
1924 PhaseGVN* gvn = initial_gvn();
1925 set_inlining_incrementally(true);
1926
1927 assert( igvn._worklist.size() == 0, "should be done with igvn" );
1928 for_igvn()->clear();
1929 gvn->replace_with(&igvn);
1930
1931 _late_inlines_pos = _late_inlines.length();
1932
1933 while (_boxing_late_inlines.length() > 0) {
1934 CallGenerator* cg = _boxing_late_inlines.pop();
1935 cg->do_late_inline();
1936 if (failing()) return;
1937 }
1938 _boxing_late_inlines.trunc_to(0);
1939
1940 {
1941 ResourceMark rm;
1942 PhaseRemoveUseless pru(gvn, for_igvn());
1943 }
1944
1945 igvn = PhaseIterGVN(gvn);
1946 igvn.optimize();
1947
1948 set_inlining_progress(false);
1949 set_inlining_incrementally(false);
1950 }
1951 }
1952
1953 void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
1954 assert(IncrementalInline, "incremental inlining should be on");
1955 PhaseGVN* gvn = initial_gvn();
1956
1957 set_inlining_progress(false);
1958 for_igvn()->clear();
1959 gvn->replace_with(&igvn);
1960
1961 {
1962 TracePhase tp("incrementalInline_inline", &timers[_t_incrInline_inline]);
1963 int i = 0;
1964 for (; i <_late_inlines.length() && !inlining_progress(); i++) {
1965 CallGenerator* cg = _late_inlines.at(i);
1966 _late_inlines_pos = i+1;
1967 cg->do_late_inline();
1968 if (failing()) return;
1969 }
1970 int j = 0;
1971 for (; i < _late_inlines.length(); i++, j++) {
1972 _late_inlines.at_put(j, _late_inlines.at(i));
1973 }
1974 _late_inlines.trunc_to(j);
1975 }
1976
1977 {
1978 TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
1979 ResourceMark rm;
1980 PhaseRemoveUseless pru(gvn, for_igvn());
1981 }
1982
1983 {
1984 TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
1985 igvn = PhaseIterGVN(gvn);
1986 }
1987 }
1988
1989 // Perform incremental inlining until bound on number of live nodes is reached
1990 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
1991 TracePhase tp("incrementalInline", &timers[_t_incrInline]);
1992
1993 PhaseGVN* gvn = initial_gvn();
1994
1995 set_inlining_incrementally(true);
1996 set_inlining_progress(true);
1997 uint low_live_nodes = 0;
1998
1999 while(inlining_progress() && _late_inlines.length() > 0) {
2000
2001 if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2002 if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
2003 TracePhase tp("incrementalInline_ideal", &timers[_t_incrInline_ideal]);
2004 // PhaseIdealLoop is expensive so we only try it once we are
2005 // out of live nodes and we only try it again if the previous
2006 // helped got the number of nodes down significantly
2007 PhaseIdealLoop ideal_loop( igvn, false, true );
2008 if (failing()) return;
2009 low_live_nodes = live_nodes();
2010 _major_progress = true;
2011 }
2012
2013 if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2014 break;
2015 }
2016 }
2017
2018 inline_incrementally_one(igvn);
2019
2020 if (failing()) return;
2021
2022 {
2023 TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2024 igvn.optimize();
2025 }
2026
2027 if (failing()) return;
2028 }
2029
2030 assert( igvn._worklist.size() == 0, "should be done with igvn" );
2031
2032 if (_string_late_inlines.length() > 0) {
2033 assert(has_stringbuilder(), "inconsistent");
2034 for_igvn()->clear();
2035 initial_gvn()->replace_with(&igvn);
2036
2037 inline_string_calls(false);
2038
2039 if (failing()) return;
2040
2041 {
2042 TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
2043 ResourceMark rm;
2044 PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2045 }
2046
2047 {
2048 TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2049 igvn = PhaseIterGVN(gvn);
2050 igvn.optimize();
2051 }
2052 }
2053
2054 set_inlining_incrementally(false);
2055 }
2056
2057
2058 //------------------------------Optimize---------------------------------------
2059 // Given a graph, optimize it.
2060 void Compile::Optimize() {
2061 TracePhase tp("optimizer", &timers[_t_optimizer]);
2062
2063 #ifndef PRODUCT
2064 if (env()->break_at_compile()) {
2065 BREAKPOINT;
2066 }
2067
2068 #endif
2069
2070 ResourceMark rm;
2071 int loop_opts_cnt;
2072
2073 print_inlining_reinit();
2074
2075 NOT_PRODUCT( verify_graph_edges(); )
2076
2077 print_method(PHASE_AFTER_PARSING);
2078
2079 {
2080 // Iterative Global Value Numbering, including ideal transforms
2081 // Initialize IterGVN with types and values from parse-time GVN
2082 PhaseIterGVN igvn(initial_gvn());
2083 #ifdef ASSERT
2084 _modified_nodes = new (comp_arena()) Unique_Node_List(comp_arena());
2085 #endif
2086 {
2087 TracePhase tp("iterGVN", &timers[_t_iterGVN]);
2088 igvn.optimize();
2089 }
2090
2091 print_method(PHASE_ITER_GVN1, 2);
2092
2093 if (failing()) return;
2094
2095 inline_incrementally(igvn);
2096
2097 print_method(PHASE_INCREMENTAL_INLINE, 2);
2098
2099 if (failing()) return;
2100
2101 if (eliminate_boxing()) {
2102 // Inline valueOf() methods now.
2103 inline_boxing_calls(igvn);
2104
2105 if (AlwaysIncrementalInline) {
2106 inline_incrementally(igvn);
2107 }
2108
2109 print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
2110
2111 if (failing()) return;
2112 }
2113
2114 // Remove the speculative part of types and clean up the graph from
2115 // the extra CastPP nodes whose only purpose is to carry them. Do
2116 // that early so that optimizations are not disrupted by the extra
2117 // CastPP nodes.
2118 remove_speculative_types(igvn);
2119
2120 // No more new expensive nodes will be added to the list from here
2121 // so keep only the actual candidates for optimizations.
2122 cleanup_expensive_nodes(igvn);
2123
2124 // Perform escape analysis
2125 if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
2126 if (has_loops()) {
2127 // Cleanup graph (remove dead nodes).
2128 TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2129 PhaseIdealLoop ideal_loop( igvn, false, true );
2130 if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
2131 if (failing()) return;
2132 }
2133 ConnectionGraph::do_analysis(this, &igvn);
2134
2135 if (failing()) return;
2136
2137 // Optimize out fields loads from scalar replaceable allocations.
2138 igvn.optimize();
2139 print_method(PHASE_ITER_GVN_AFTER_EA, 2);
2140
2141 if (failing()) return;
2142
2143 if (congraph() != NULL && macro_count() > 0) {
2144 TracePhase tp("macroEliminate", &timers[_t_macroEliminate]);
2145 PhaseMacroExpand mexp(igvn);
2146 mexp.eliminate_macro_nodes();
2147 igvn.set_delay_transform(false);
2148
2149 igvn.optimize();
2150 print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
2151
2152 if (failing()) return;
2153 }
2154 }
2155
2156 // Loop transforms on the ideal graph. Range Check Elimination,
2157 // peeling, unrolling, etc.
2158
2159 // Set loop opts counter
2160 loop_opts_cnt = num_loop_opts();
2161 if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
2162 {
2163 TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2164 PhaseIdealLoop ideal_loop( igvn, true );
2165 loop_opts_cnt--;
2166 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
2167 if (failing()) return;
2168 }
2169 // Loop opts pass if partial peeling occurred in previous pass
2170 if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
2171 TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2172 PhaseIdealLoop ideal_loop( igvn, false );
2173 loop_opts_cnt--;
2174 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
2175 if (failing()) return;
2176 }
2177 // Loop opts pass for loop-unrolling before CCP
2178 if(major_progress() && (loop_opts_cnt > 0)) {
2179 TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2180 PhaseIdealLoop ideal_loop( igvn, false );
2181 loop_opts_cnt--;
2182 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
2183 }
2184 if (!failing()) {
2185 // Verify that last round of loop opts produced a valid graph
2186 TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2187 PhaseIdealLoop::verify(igvn);
2188 }
2189 }
2190 if (failing()) return;
2191
2192 // Conditional Constant Propagation;
2193 PhaseCCP ccp( &igvn );
2194 assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
2195 {
2196 TracePhase tp("ccp", &timers[_t_ccp]);
2197 ccp.do_transform();
2198 }
2199 print_method(PHASE_CPP1, 2);
2200
2201 assert( true, "Break here to ccp.dump_old2new_map()");
2202
2203 // Iterative Global Value Numbering, including ideal transforms
2204 {
2205 TracePhase tp("iterGVN2", &timers[_t_iterGVN2]);
2206 igvn = ccp;
2207 igvn.optimize();
2208 }
2209
2210 print_method(PHASE_ITER_GVN2, 2);
2211
2212 if (failing()) return;
2213
2214 // Loop transforms on the ideal graph. Range Check Elimination,
2215 // peeling, unrolling, etc.
2216 if(loop_opts_cnt > 0) {
2217 debug_only( int cnt = 0; );
2218 while(major_progress() && (loop_opts_cnt > 0)) {
2219 TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2220 assert( cnt++ < 40, "infinite cycle in loop optimization" );
2221 PhaseIdealLoop ideal_loop( igvn, true);
2222 loop_opts_cnt--;
2223 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
2224 if (failing()) return;
2225 }
2226 }
2227
2228 {
2229 // Verify that all previous optimizations produced a valid graph
2230 // at least to this point, even if no loop optimizations were done.
2231 TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2232 PhaseIdealLoop::verify(igvn);
2233 }
2234
2235 {
2236 TracePhase tp("macroExpand", &timers[_t_macroExpand]);
2237 PhaseMacroExpand mex(igvn);
2238 if (mex.expand_macro_nodes()) {
2239 assert(failing(), "must bail out w/ explicit message");
2240 return;
2241 }
2242 }
2243
2244 DEBUG_ONLY( _modified_nodes = NULL; )
2245 } // (End scope of igvn; run destructor if necessary for asserts.)
2246
2247 process_print_inlining();
2248 // A method with only infinite loops has no edges entering loops from root
2249 {
2250 TracePhase tp("graphReshape", &timers[_t_graphReshaping]);
2251 if (final_graph_reshaping()) {
2252 assert(failing(), "must bail out w/ explicit message");
2253 return;
2254 }
2255 }
2256
2257 print_method(PHASE_OPTIMIZE_FINISHED, 2);
2258 }
2259
2260
2261 //------------------------------Code_Gen---------------------------------------
2262 // Given a graph, generate code for it
2263 void Compile::Code_Gen() {
2264 if (failing()) {
2265 return;
2266 }
2267
2268 // Perform instruction selection. You might think we could reclaim Matcher
2269 // memory PDQ, but actually the Matcher is used in generating spill code.
2270 // Internals of the Matcher (including some VectorSets) must remain live
2271 // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
2272 // set a bit in reclaimed memory.
2273
2274 // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2275 // nodes. Mapping is only valid at the root of each matched subtree.
2276 NOT_PRODUCT( verify_graph_edges(); )
2277
2278 Matcher matcher;
2279 _matcher = &matcher;
2280 {
2281 TracePhase tp("matcher", &timers[_t_matcher]);
2282 matcher.match();
2283 }
2284 // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2285 // nodes. Mapping is only valid at the root of each matched subtree.
2286 NOT_PRODUCT( verify_graph_edges(); )
2287
2288 // If you have too many nodes, or if matching has failed, bail out
2289 check_node_count(0, "out of nodes matching instructions");
2290 if (failing()) {
2291 return;
2292 }
2293
2294 // Build a proper-looking CFG
2295 PhaseCFG cfg(node_arena(), root(), matcher);
2296 _cfg = &cfg;
2297 {
2298 TracePhase tp("scheduler", &timers[_t_scheduler]);
2299 bool success = cfg.do_global_code_motion();
2300 if (!success) {
2301 return;
2302 }
2303
2304 print_method(PHASE_GLOBAL_CODE_MOTION, 2);
2305 NOT_PRODUCT( verify_graph_edges(); )
2306 debug_only( cfg.verify(); )
2307 }
2308
2309 PhaseChaitin regalloc(unique(), cfg, matcher);
2310 _regalloc = ®alloc;
2311 {
2312 TracePhase tp("regalloc", &timers[_t_registerAllocation]);
2313 // Perform register allocation. After Chaitin, use-def chains are
2314 // no longer accurate (at spill code) and so must be ignored.
2315 // Node->LRG->reg mappings are still accurate.
2316 _regalloc->Register_Allocate();
2317
2318 // Bail out if the allocator builds too many nodes
2319 if (failing()) {
2320 return;
2321 }
2322 }
2323
2324 // Prior to register allocation we kept empty basic blocks in case the
2325 // the allocator needed a place to spill. After register allocation we
2326 // are not adding any new instructions. If any basic block is empty, we
2327 // can now safely remove it.
2328 {
2329 TracePhase tp("blockOrdering", &timers[_t_blockOrdering]);
2330 cfg.remove_empty_blocks();
2331 if (do_freq_based_layout()) {
2332 PhaseBlockLayout layout(cfg);
2333 } else {
2334 cfg.set_loop_alignment();
2335 }
2336 cfg.fixup_flow();
2337 }
2338
2339 // Apply peephole optimizations
2340 if( OptoPeephole ) {
2341 TracePhase tp("peephole", &timers[_t_peephole]);
2342 PhasePeephole peep( _regalloc, cfg);
2343 peep.do_transform();
2344 }
2345
2346 // Do late expand if CPU requires this.
2347 if (Matcher::require_postalloc_expand) {
2348 TracePhase tp("postalloc_expand", &timers[_t_postalloc_expand]);
2349 cfg.postalloc_expand(_regalloc);
2350 }
2351
2352 // Convert Nodes to instruction bits in a buffer
2353 {
2354 TraceTime tp("output", &timers[_t_output], CITime);
2355 Output();
2356 }
2357
2358 print_method(PHASE_FINAL_CODE);
2359
2360 // He's dead, Jim.
2361 _cfg = (PhaseCFG*)0xdeadbeef;
2362 _regalloc = (PhaseChaitin*)0xdeadbeef;
2363 }
2364
2365
2366 //------------------------------dump_asm---------------------------------------
2367 // Dump formatted assembly
2368 #ifndef PRODUCT
2369 void Compile::dump_asm(int *pcs, uint pc_limit) {
2370 bool cut_short = false;
2371 tty->print_cr("#");
2372 tty->print("# "); _tf->dump(); tty->cr();
2373 tty->print_cr("#");
2374
2375 // For all blocks
2376 int pc = 0x0; // Program counter
2377 char starts_bundle = ' ';
2378 _regalloc->dump_frame();
2379
2380 Node *n = NULL;
2381 for (uint i = 0; i < _cfg->number_of_blocks(); i++) {
2382 if (VMThread::should_terminate()) {
2383 cut_short = true;
2384 break;
2385 }
2386 Block* block = _cfg->get_block(i);
2387 if (block->is_connector() && !Verbose) {
2388 continue;
2389 }
2390 n = block->head();
2391 if (pcs && n->_idx < pc_limit) {
2392 tty->print("%3.3x ", pcs[n->_idx]);
2393 } else {
2394 tty->print(" ");
2395 }
2396 block->dump_head(_cfg);
2397 if (block->is_connector()) {
2398 tty->print_cr(" # Empty connector block");
2399 } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
2400 tty->print_cr(" # Block is sole successor of call");
2401 }
2402
2403 // For all instructions
2404 Node *delay = NULL;
2405 for (uint j = 0; j < block->number_of_nodes(); j++) {
2406 if (VMThread::should_terminate()) {
2407 cut_short = true;
2408 break;
2409 }
2410 n = block->get_node(j);
2411 if (valid_bundle_info(n)) {
2412 Bundle* bundle = node_bundling(n);
2413 if (bundle->used_in_unconditional_delay()) {
2414 delay = n;
2415 continue;
2416 }
2417 if (bundle->starts_bundle()) {
2418 starts_bundle = '+';
2419 }
2420 }
2421
2422 if (WizardMode) {
2423 n->dump();
2424 }
2425
2426 if( !n->is_Region() && // Dont print in the Assembly
2427 !n->is_Phi() && // a few noisely useless nodes
2428 !n->is_Proj() &&
2429 !n->is_MachTemp() &&
2430 !n->is_SafePointScalarObject() &&
2431 !n->is_Catch() && // Would be nice to print exception table targets
2432 !n->is_MergeMem() && // Not very interesting
2433 !n->is_top() && // Debug info table constants
2434 !(n->is_Con() && !n->is_Mach())// Debug info table constants
2435 ) {
2436 if (pcs && n->_idx < pc_limit)
2437 tty->print("%3.3x", pcs[n->_idx]);
2438 else
2439 tty->print(" ");
2440 tty->print(" %c ", starts_bundle);
2441 starts_bundle = ' ';
2442 tty->print("\t");
2443 n->format(_regalloc, tty);
2444 tty->cr();
2445 }
2446
2447 // If we have an instruction with a delay slot, and have seen a delay,
2448 // then back up and print it
2449 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
2450 assert(delay != NULL, "no unconditional delay instruction");
2451 if (WizardMode) delay->dump();
2452
2453 if (node_bundling(delay)->starts_bundle())
2454 starts_bundle = '+';
2455 if (pcs && n->_idx < pc_limit)
2456 tty->print("%3.3x", pcs[n->_idx]);
2457 else
2458 tty->print(" ");
2459 tty->print(" %c ", starts_bundle);
2460 starts_bundle = ' ';
2461 tty->print("\t");
2462 delay->format(_regalloc, tty);
2463 tty->cr();
2464 delay = NULL;
2465 }
2466
2467 // Dump the exception table as well
2468 if( n->is_Catch() && (Verbose || WizardMode) ) {
2469 // Print the exception table for this offset
2470 _handler_table.print_subtable_for(pc);
2471 }
2472 }
2473
2474 if (pcs && n->_idx < pc_limit)
2475 tty->print_cr("%3.3x", pcs[n->_idx]);
2476 else
2477 tty->cr();
2478
2479 assert(cut_short || delay == NULL, "no unconditional delay branch");
2480
2481 } // End of per-block dump
2482 tty->cr();
2483
2484 if (cut_short) tty->print_cr("*** disassembly is cut short ***");
2485 }
2486 #endif
2487
2488 //------------------------------Final_Reshape_Counts---------------------------
2489 // This class defines counters to help identify when a method
2490 // may/must be executed using hardware with only 24-bit precision.
2491 struct Final_Reshape_Counts : public StackObj {
2492 int _call_count; // count non-inlined 'common' calls
2493 int _float_count; // count float ops requiring 24-bit precision
2494 int _double_count; // count double ops requiring more precision
2495 int _java_call_count; // count non-inlined 'java' calls
2496 int _inner_loop_count; // count loops which need alignment
2497 VectorSet _visited; // Visitation flags
2498 Node_List _tests; // Set of IfNodes & PCTableNodes
2499
2500 Final_Reshape_Counts() :
2501 _call_count(0), _float_count(0), _double_count(0),
2502 _java_call_count(0), _inner_loop_count(0),
2503 _visited( Thread::current()->resource_area() ) { }
2504
2505 void inc_call_count () { _call_count ++; }
2506 void inc_float_count () { _float_count ++; }
2507 void inc_double_count() { _double_count++; }
2508 void inc_java_call_count() { _java_call_count++; }
2509 void inc_inner_loop_count() { _inner_loop_count++; }
2510
2511 int get_call_count () const { return _call_count ; }
2512 int get_float_count () const { return _float_count ; }
2513 int get_double_count() const { return _double_count; }
2514 int get_java_call_count() const { return _java_call_count; }
2515 int get_inner_loop_count() const { return _inner_loop_count; }
2516 };
2517
2518 #ifdef ASSERT
2519 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
2520 ciInstanceKlass *k = tp->klass()->as_instance_klass();
2521 // Make sure the offset goes inside the instance layout.
2522 return k->contains_field_offset(tp->offset());
2523 // Note that OffsetBot and OffsetTop are very negative.
2524 }
2525 #endif
2526
2527 // Eliminate trivially redundant StoreCMs and accumulate their
2528 // precedence edges.
2529 void Compile::eliminate_redundant_card_marks(Node* n) {
2530 assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
2531 if (n->in(MemNode::Address)->outcnt() > 1) {
2532 // There are multiple users of the same address so it might be
2533 // possible to eliminate some of the StoreCMs
2534 Node* mem = n->in(MemNode::Memory);
2535 Node* adr = n->in(MemNode::Address);
2536 Node* val = n->in(MemNode::ValueIn);
2537 Node* prev = n;
2538 bool done = false;
2539 // Walk the chain of StoreCMs eliminating ones that match. As
2540 // long as it's a chain of single users then the optimization is
2541 // safe. Eliminating partially redundant StoreCMs would require
2542 // cloning copies down the other paths.
2543 while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
2544 if (adr == mem->in(MemNode::Address) &&
2545 val == mem->in(MemNode::ValueIn)) {
2546 // redundant StoreCM
2547 if (mem->req() > MemNode::OopStore) {
2548 // Hasn't been processed by this code yet.
2549 n->add_prec(mem->in(MemNode::OopStore));
2550 } else {
2551 // Already converted to precedence edge
2552 for (uint i = mem->req(); i < mem->len(); i++) {
2553 // Accumulate any precedence edges
2554 if (mem->in(i) != NULL) {
2555 n->add_prec(mem->in(i));
2556 }
2557 }
2558 // Everything above this point has been processed.
2559 done = true;
2560 }
2561 // Eliminate the previous StoreCM
2562 prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
2563 assert(mem->outcnt() == 0, "should be dead");
2564 mem->disconnect_inputs(NULL, this);
2565 } else {
2566 prev = mem;
2567 }
2568 mem = prev->in(MemNode::Memory);
2569 }
2570 }
2571 }
2572
2573 //------------------------------final_graph_reshaping_impl----------------------
2574 // Implement items 1-5 from final_graph_reshaping below.
2575 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
2576
2577 if ( n->outcnt() == 0 ) return; // dead node
2578 uint nop = n->Opcode();
2579
2580 // Check for 2-input instruction with "last use" on right input.
2581 // Swap to left input. Implements item (2).
2582 if( n->req() == 3 && // two-input instruction
2583 n->in(1)->outcnt() > 1 && // left use is NOT a last use
2584 (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
2585 n->in(2)->outcnt() == 1 &&// right use IS a last use
2586 !n->in(2)->is_Con() ) { // right use is not a constant
2587 // Check for commutative opcode
2588 switch( nop ) {
2589 case Op_AddI: case Op_AddF: case Op_AddD: case Op_AddL:
2590 case Op_MaxI: case Op_MinI:
2591 case Op_MulI: case Op_MulF: case Op_MulD: case Op_MulL:
2592 case Op_AndL: case Op_XorL: case Op_OrL:
2593 case Op_AndI: case Op_XorI: case Op_OrI: {
2594 // Move "last use" input to left by swapping inputs
2595 n->swap_edges(1, 2);
2596 break;
2597 }
2598 default:
2599 break;
2600 }
2601 }
2602
2603 #ifdef ASSERT
2604 if( n->is_Mem() ) {
2605 int alias_idx = get_alias_index(n->as_Mem()->adr_type());
2606 assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
2607 // oop will be recorded in oop map if load crosses safepoint
2608 n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
2609 LoadNode::is_immutable_value(n->in(MemNode::Address))),
2610 "raw memory operations should have control edge");
2611 }
2612 #endif
2613 // Count FPU ops and common calls, implements item (3)
2614 switch( nop ) {
2615 // Count all float operations that may use FPU
2616 case Op_AddF:
2617 case Op_SubF:
2618 case Op_MulF:
2619 case Op_DivF:
2620 case Op_NegF:
2621 case Op_ModF:
2622 case Op_ConvI2F:
2623 case Op_ConF:
2624 case Op_CmpF:
2625 case Op_CmpF3:
2626 // case Op_ConvL2F: // longs are split into 32-bit halves
2627 frc.inc_float_count();
2628 break;
2629
2630 case Op_ConvF2D:
2631 case Op_ConvD2F:
2632 frc.inc_float_count();
2633 frc.inc_double_count();
2634 break;
2635
2636 // Count all double operations that may use FPU
2637 case Op_AddD:
2638 case Op_SubD:
2639 case Op_MulD:
2640 case Op_DivD:
2641 case Op_NegD:
2642 case Op_ModD:
2643 case Op_ConvI2D:
2644 case Op_ConvD2I:
2645 // case Op_ConvL2D: // handled by leaf call
2646 // case Op_ConvD2L: // handled by leaf call
2647 case Op_ConD:
2648 case Op_CmpD:
2649 case Op_CmpD3:
2650 frc.inc_double_count();
2651 break;
2652 case Op_Opaque1: // Remove Opaque Nodes before matching
2653 case Op_Opaque2: // Remove Opaque Nodes before matching
2654 case Op_Opaque3:
2655 n->subsume_by(n->in(1), this);
2656 break;
2657 case Op_CallStaticJava:
2658 case Op_CallJava:
2659 case Op_CallDynamicJava:
2660 frc.inc_java_call_count(); // Count java call site;
2661 case Op_CallRuntime:
2662 case Op_CallLeaf:
2663 case Op_CallLeafNoFP: {
2664 assert( n->is_Call(), "" );
2665 CallNode *call = n->as_Call();
2666 // Count call sites where the FP mode bit would have to be flipped.
2667 // Do not count uncommon runtime calls:
2668 // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
2669 // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
2670 if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
2671 frc.inc_call_count(); // Count the call site
2672 } else { // See if uncommon argument is shared
2673 Node *n = call->in(TypeFunc::Parms);
2674 int nop = n->Opcode();
2675 // Clone shared simple arguments to uncommon calls, item (1).
2676 if( n->outcnt() > 1 &&
2677 !n->is_Proj() &&
2678 nop != Op_CreateEx &&
2679 nop != Op_CheckCastPP &&
2680 nop != Op_DecodeN &&
2681 nop != Op_DecodeNKlass &&
2682 !n->is_Mem() ) {
2683 Node *x = n->clone();
2684 call->set_req( TypeFunc::Parms, x );
2685 }
2686 }
2687 break;
2688 }
2689
2690 case Op_StoreD:
2691 case Op_LoadD:
2692 case Op_LoadD_unaligned:
2693 frc.inc_double_count();
2694 goto handle_mem;
2695 case Op_StoreF:
2696 case Op_LoadF:
2697 frc.inc_float_count();
2698 goto handle_mem;
2699
2700 case Op_StoreCM:
2701 {
2702 // Convert OopStore dependence into precedence edge
2703 Node* prec = n->in(MemNode::OopStore);
2704 n->del_req(MemNode::OopStore);
2705 n->add_prec(prec);
2706 eliminate_redundant_card_marks(n);
2707 }
2708
2709 // fall through
2710
2711 case Op_StoreB:
2712 case Op_StoreC:
2713 case Op_StorePConditional:
2714 case Op_StoreI:
2715 case Op_StoreL:
2716 case Op_StoreIConditional:
2717 case Op_StoreLConditional:
2718 case Op_CompareAndSwapI:
2719 case Op_CompareAndSwapL:
2720 case Op_CompareAndSwapP:
2721 case Op_CompareAndSwapN:
2722 case Op_GetAndAddI:
2723 case Op_GetAndAddL:
2724 case Op_GetAndSetI:
2725 case Op_GetAndSetL:
2726 case Op_GetAndSetP:
2727 case Op_GetAndSetN:
2728 case Op_StoreP:
2729 case Op_StoreN:
2730 case Op_StoreNKlass:
2731 case Op_LoadB:
2732 case Op_LoadUB:
2733 case Op_LoadUS:
2734 case Op_LoadI:
2735 case Op_LoadKlass:
2736 case Op_LoadNKlass:
2737 case Op_LoadL:
2738 case Op_LoadL_unaligned:
2739 case Op_LoadPLocked:
2740 case Op_LoadP:
2741 case Op_LoadN:
2742 case Op_LoadRange:
2743 case Op_LoadS: {
2744 handle_mem:
2745 #ifdef ASSERT
2746 if( VerifyOptoOopOffsets ) {
2747 assert( n->is_Mem(), "" );
2748 MemNode *mem = (MemNode*)n;
2749 // Check to see if address types have grounded out somehow.
2750 const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
2751 assert( !tp || oop_offset_is_sane(tp), "" );
2752 }
2753 #endif
2754 break;
2755 }
2756
2757 case Op_AddP: { // Assert sane base pointers
2758 Node *addp = n->in(AddPNode::Address);
2759 assert( !addp->is_AddP() ||
2760 addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
2761 addp->in(AddPNode::Base) == n->in(AddPNode::Base),
2762 "Base pointers must match" );
2763 #ifdef _LP64
2764 if ((UseCompressedOops || UseCompressedClassPointers) &&
2765 addp->Opcode() == Op_ConP &&
2766 addp == n->in(AddPNode::Base) &&
2767 n->in(AddPNode::Offset)->is_Con()) {
2768 // Use addressing with narrow klass to load with offset on x86.
2769 // On sparc loading 32-bits constant and decoding it have less
2770 // instructions (4) then load 64-bits constant (7).
2771 // Do this transformation here since IGVN will convert ConN back to ConP.
2772 const Type* t = addp->bottom_type();
2773 if (t->isa_oopptr() || t->isa_klassptr()) {
2774 Node* nn = NULL;
2775
2776 int op = t->isa_oopptr() ? Op_ConN : Op_ConNKlass;
2777
2778 // Look for existing ConN node of the same exact type.
2779 Node* r = root();
2780 uint cnt = r->outcnt();
2781 for (uint i = 0; i < cnt; i++) {
2782 Node* m = r->raw_out(i);
2783 if (m!= NULL && m->Opcode() == op &&
2784 m->bottom_type()->make_ptr() == t) {
2785 nn = m;
2786 break;
2787 }
2788 }
2789 if (nn != NULL) {
2790 // Decode a narrow oop to match address
2791 // [R12 + narrow_oop_reg<<3 + offset]
2792 if (t->isa_oopptr()) {
2793 nn = new DecodeNNode(nn, t);
2794 } else {
2795 nn = new DecodeNKlassNode(nn, t);
2796 }
2797 n->set_req(AddPNode::Base, nn);
2798 n->set_req(AddPNode::Address, nn);
2799 if (addp->outcnt() == 0) {
2800 addp->disconnect_inputs(NULL, this);
2801 }
2802 }
2803 }
2804 }
2805 #endif
2806 break;
2807 }
2808
2809 #ifdef _LP64
2810 case Op_CastPP:
2811 if (n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
2812 Node* in1 = n->in(1);
2813 const Type* t = n->bottom_type();
2814 Node* new_in1 = in1->clone();
2815 new_in1->as_DecodeN()->set_type(t);
2816
2817 if (!Matcher::narrow_oop_use_complex_address()) {
2818 //
2819 // x86, ARM and friends can handle 2 adds in addressing mode
2820 // and Matcher can fold a DecodeN node into address by using
2821 // a narrow oop directly and do implicit NULL check in address:
2822 //
2823 // [R12 + narrow_oop_reg<<3 + offset]
2824 // NullCheck narrow_oop_reg
2825 //
2826 // On other platforms (Sparc) we have to keep new DecodeN node and
2827 // use it to do implicit NULL check in address:
2828 //
2829 // decode_not_null narrow_oop_reg, base_reg
2830 // [base_reg + offset]
2831 // NullCheck base_reg
2832 //
2833 // Pin the new DecodeN node to non-null path on these platform (Sparc)
2834 // to keep the information to which NULL check the new DecodeN node
2835 // corresponds to use it as value in implicit_null_check().
2836 //
2837 new_in1->set_req(0, n->in(0));
2838 }
2839
2840 n->subsume_by(new_in1, this);
2841 if (in1->outcnt() == 0) {
2842 in1->disconnect_inputs(NULL, this);
2843 }
2844 }
2845 break;
2846
2847 case Op_CmpP:
2848 // Do this transformation here to preserve CmpPNode::sub() and
2849 // other TypePtr related Ideal optimizations (for example, ptr nullness).
2850 if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
2851 Node* in1 = n->in(1);
2852 Node* in2 = n->in(2);
2853 if (!in1->is_DecodeNarrowPtr()) {
2854 in2 = in1;
2855 in1 = n->in(2);
2856 }
2857 assert(in1->is_DecodeNarrowPtr(), "sanity");
2858
2859 Node* new_in2 = NULL;
2860 if (in2->is_DecodeNarrowPtr()) {
2861 assert(in2->Opcode() == in1->Opcode(), "must be same node type");
2862 new_in2 = in2->in(1);
2863 } else if (in2->Opcode() == Op_ConP) {
2864 const Type* t = in2->bottom_type();
2865 if (t == TypePtr::NULL_PTR) {
2866 assert(in1->is_DecodeN(), "compare klass to null?");
2867 // Don't convert CmpP null check into CmpN if compressed
2868 // oops implicit null check is not generated.
2869 // This will allow to generate normal oop implicit null check.
2870 if (Matcher::gen_narrow_oop_implicit_null_checks())
2871 new_in2 = ConNode::make(TypeNarrowOop::NULL_PTR);
2872 //
2873 // This transformation together with CastPP transformation above
2874 // will generated code for implicit NULL checks for compressed oops.
2875 //
2876 // The original code after Optimize()
2877 //
2878 // LoadN memory, narrow_oop_reg
2879 // decode narrow_oop_reg, base_reg
2880 // CmpP base_reg, NULL
2881 // CastPP base_reg // NotNull
2882 // Load [base_reg + offset], val_reg
2883 //
2884 // after these transformations will be
2885 //
2886 // LoadN memory, narrow_oop_reg
2887 // CmpN narrow_oop_reg, NULL
2888 // decode_not_null narrow_oop_reg, base_reg
2889 // Load [base_reg + offset], val_reg
2890 //
2891 // and the uncommon path (== NULL) will use narrow_oop_reg directly
2892 // since narrow oops can be used in debug info now (see the code in
2893 // final_graph_reshaping_walk()).
2894 //
2895 // At the end the code will be matched to
2896 // on x86:
2897 //
2898 // Load_narrow_oop memory, narrow_oop_reg
2899 // Load [R12 + narrow_oop_reg<<3 + offset], val_reg
2900 // NullCheck narrow_oop_reg
2901 //
2902 // and on sparc:
2903 //
2904 // Load_narrow_oop memory, narrow_oop_reg
2905 // decode_not_null narrow_oop_reg, base_reg
2906 // Load [base_reg + offset], val_reg
2907 // NullCheck base_reg
2908 //
2909 } else if (t->isa_oopptr()) {
2910 new_in2 = ConNode::make(t->make_narrowoop());
2911 } else if (t->isa_klassptr()) {
2912 new_in2 = ConNode::make(t->make_narrowklass());
2913 }
2914 }
2915 if (new_in2 != NULL) {
2916 Node* cmpN = new CmpNNode(in1->in(1), new_in2);
2917 n->subsume_by(cmpN, this);
2918 if (in1->outcnt() == 0) {
2919 in1->disconnect_inputs(NULL, this);
2920 }
2921 if (in2->outcnt() == 0) {
2922 in2->disconnect_inputs(NULL, this);
2923 }
2924 }
2925 }
2926 break;
2927
2928 case Op_DecodeN:
2929 case Op_DecodeNKlass:
2930 assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
2931 // DecodeN could be pinned when it can't be fold into
2932 // an address expression, see the code for Op_CastPP above.
2933 assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
2934 break;
2935
2936 case Op_EncodeP:
2937 case Op_EncodePKlass: {
2938 Node* in1 = n->in(1);
2939 if (in1->is_DecodeNarrowPtr()) {
2940 n->subsume_by(in1->in(1), this);
2941 } else if (in1->Opcode() == Op_ConP) {
2942 const Type* t = in1->bottom_type();
2943 if (t == TypePtr::NULL_PTR) {
2944 assert(t->isa_oopptr(), "null klass?");
2945 n->subsume_by(ConNode::make(TypeNarrowOop::NULL_PTR), this);
2946 } else if (t->isa_oopptr()) {
2947 n->subsume_by(ConNode::make(t->make_narrowoop()), this);
2948 } else if (t->isa_klassptr()) {
2949 n->subsume_by(ConNode::make(t->make_narrowklass()), this);
2950 }
2951 }
2952 if (in1->outcnt() == 0) {
2953 in1->disconnect_inputs(NULL, this);
2954 }
2955 break;
2956 }
2957
2958 case Op_Proj: {
2959 if (OptimizeStringConcat) {
2960 ProjNode* p = n->as_Proj();
2961 if (p->_is_io_use) {
2962 // Separate projections were used for the exception path which
2963 // are normally removed by a late inline. If it wasn't inlined
2964 // then they will hang around and should just be replaced with
2965 // the original one.
2966 Node* proj = NULL;
2967 // Replace with just one
2968 for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
2969 Node *use = i.get();
2970 if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
2971 proj = use;
2972 break;
2973 }
2974 }
2975 assert(proj != NULL, "must be found");
2976 p->subsume_by(proj, this);
2977 }
2978 }
2979 break;
2980 }
2981
2982 case Op_Phi:
2983 if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
2984 // The EncodeP optimization may create Phi with the same edges
2985 // for all paths. It is not handled well by Register Allocator.
2986 Node* unique_in = n->in(1);
2987 assert(unique_in != NULL, "");
2988 uint cnt = n->req();
2989 for (uint i = 2; i < cnt; i++) {
2990 Node* m = n->in(i);
2991 assert(m != NULL, "");
2992 if (unique_in != m)
2993 unique_in = NULL;
2994 }
2995 if (unique_in != NULL) {
2996 n->subsume_by(unique_in, this);
2997 }
2998 }
2999 break;
3000
3001 #endif
3002
3003 case Op_ModI:
3004 if (UseDivMod) {
3005 // Check if a%b and a/b both exist
3006 Node* d = n->find_similar(Op_DivI);
3007 if (d) {
3008 // Replace them with a fused divmod if supported
3009 if (Matcher::has_match_rule(Op_DivModI)) {
3010 DivModINode* divmod = DivModINode::make(n);
3011 d->subsume_by(divmod->div_proj(), this);
3012 n->subsume_by(divmod->mod_proj(), this);
3013 } else {
3014 // replace a%b with a-((a/b)*b)
3015 Node* mult = new MulINode(d, d->in(2));
3016 Node* sub = new SubINode(d->in(1), mult);
3017 n->subsume_by(sub, this);
3018 }
3019 }
3020 }
3021 break;
3022
3023 case Op_ModL:
3024 if (UseDivMod) {
3025 // Check if a%b and a/b both exist
3026 Node* d = n->find_similar(Op_DivL);
3027 if (d) {
3028 // Replace them with a fused divmod if supported
3029 if (Matcher::has_match_rule(Op_DivModL)) {
3030 DivModLNode* divmod = DivModLNode::make(n);
3031 d->subsume_by(divmod->div_proj(), this);
3032 n->subsume_by(divmod->mod_proj(), this);
3033 } else {
3034 // replace a%b with a-((a/b)*b)
3035 Node* mult = new MulLNode(d, d->in(2));
3036 Node* sub = new SubLNode(d->in(1), mult);
3037 n->subsume_by(sub, this);
3038 }
3039 }
3040 }
3041 break;
3042
3043 case Op_LoadVector:
3044 case Op_StoreVector:
3045 break;
3046
3047 case Op_PackB:
3048 case Op_PackS:
3049 case Op_PackI:
3050 case Op_PackF:
3051 case Op_PackL:
3052 case Op_PackD:
3053 if (n->req()-1 > 2) {
3054 // Replace many operand PackNodes with a binary tree for matching
3055 PackNode* p = (PackNode*) n;
3056 Node* btp = p->binary_tree_pack(1, n->req());
3057 n->subsume_by(btp, this);
3058 }
3059 break;
3060 case Op_Loop:
3061 case Op_CountedLoop:
3062 if (n->as_Loop()->is_inner_loop()) {
3063 frc.inc_inner_loop_count();
3064 }
3065 break;
3066 case Op_LShiftI:
3067 case Op_RShiftI:
3068 case Op_URShiftI:
3069 case Op_LShiftL:
3070 case Op_RShiftL:
3071 case Op_URShiftL:
3072 if (Matcher::need_masked_shift_count) {
3073 // The cpu's shift instructions don't restrict the count to the
3074 // lower 5/6 bits. We need to do the masking ourselves.
3075 Node* in2 = n->in(2);
3076 juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
3077 const TypeInt* t = in2->find_int_type();
3078 if (t != NULL && t->is_con()) {
3079 juint shift = t->get_con();
3080 if (shift > mask) { // Unsigned cmp
3081 n->set_req(2, ConNode::make(TypeInt::make(shift & mask)));
3082 }
3083 } else {
3084 if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
3085 Node* shift = new AndINode(in2, ConNode::make(TypeInt::make(mask)));
3086 n->set_req(2, shift);
3087 }
3088 }
3089 if (in2->outcnt() == 0) { // Remove dead node
3090 in2->disconnect_inputs(NULL, this);
3091 }
3092 }
3093 break;
3094 case Op_MemBarStoreStore:
3095 case Op_MemBarRelease:
3096 // Break the link with AllocateNode: it is no longer useful and
3097 // confuses register allocation.
3098 if (n->req() > MemBarNode::Precedent) {
3099 n->set_req(MemBarNode::Precedent, top());
3100 }
3101 break;
3102 default:
3103 assert( !n->is_Call(), "" );
3104 assert( !n->is_Mem(), "" );
3105 break;
3106 }
3107
3108 // Collect CFG split points
3109 if (n->is_MultiBranch())
3110 frc._tests.push(n);
3111 }
3112
3113 //------------------------------final_graph_reshaping_walk---------------------
3114 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
3115 // requires that the walk visits a node's inputs before visiting the node.
3116 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
3117 ResourceArea *area = Thread::current()->resource_area();
3118 Unique_Node_List sfpt(area);
3119
3120 frc._visited.set(root->_idx); // first, mark node as visited
3121 uint cnt = root->req();
3122 Node *n = root;
3123 uint i = 0;
3124 while (true) {
3125 if (i < cnt) {
3126 // Place all non-visited non-null inputs onto stack
3127 Node* m = n->in(i);
3128 ++i;
3129 if (m != NULL && !frc._visited.test_set(m->_idx)) {
3130 if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL) {
3131 // compute worst case interpreter size in case of a deoptimization
3132 update_interpreter_frame_size(m->as_SafePoint()->jvms()->interpreter_frame_size());
3133
3134 sfpt.push(m);
3135 }
3136 cnt = m->req();
3137 nstack.push(n, i); // put on stack parent and next input's index
3138 n = m;
3139 i = 0;
3140 }
3141 } else {
3142 // Now do post-visit work
3143 final_graph_reshaping_impl( n, frc );
3144 if (nstack.is_empty())
3145 break; // finished
3146 n = nstack.node(); // Get node from stack
3147 cnt = n->req();
3148 i = nstack.index();
3149 nstack.pop(); // Shift to the next node on stack
3150 }
3151 }
3152
3153 // Skip next transformation if compressed oops are not used.
3154 if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
3155 (!UseCompressedOops && !UseCompressedClassPointers))
3156 return;
3157
3158 // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
3159 // It could be done for an uncommon traps or any safepoints/calls
3160 // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
3161 while (sfpt.size() > 0) {
3162 n = sfpt.pop();
3163 JVMState *jvms = n->as_SafePoint()->jvms();
3164 assert(jvms != NULL, "sanity");
3165 int start = jvms->debug_start();
3166 int end = n->req();
3167 bool is_uncommon = (n->is_CallStaticJava() &&
3168 n->as_CallStaticJava()->uncommon_trap_request() != 0);
3169 for (int j = start; j < end; j++) {
3170 Node* in = n->in(j);
3171 if (in->is_DecodeNarrowPtr()) {
3172 bool safe_to_skip = true;
3173 if (!is_uncommon ) {
3174 // Is it safe to skip?
3175 for (uint i = 0; i < in->outcnt(); i++) {
3176 Node* u = in->raw_out(i);
3177 if (!u->is_SafePoint() ||
3178 u->is_Call() && u->as_Call()->has_non_debug_use(n)) {
3179 safe_to_skip = false;
3180 }
3181 }
3182 }
3183 if (safe_to_skip) {
3184 n->set_req(j, in->in(1));
3185 }
3186 if (in->outcnt() == 0) {
3187 in->disconnect_inputs(NULL, this);
3188 }
3189 }
3190 }
3191 }
3192 }
3193
3194 //------------------------------final_graph_reshaping--------------------------
3195 // Final Graph Reshaping.
3196 //
3197 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
3198 // and not commoned up and forced early. Must come after regular
3199 // optimizations to avoid GVN undoing the cloning. Clone constant
3200 // inputs to Loop Phis; these will be split by the allocator anyways.
3201 // Remove Opaque nodes.
3202 // (2) Move last-uses by commutative operations to the left input to encourage
3203 // Intel update-in-place two-address operations and better register usage
3204 // on RISCs. Must come after regular optimizations to avoid GVN Ideal
3205 // calls canonicalizing them back.
3206 // (3) Count the number of double-precision FP ops, single-precision FP ops
3207 // and call sites. On Intel, we can get correct rounding either by
3208 // forcing singles to memory (requires extra stores and loads after each
3209 // FP bytecode) or we can set a rounding mode bit (requires setting and
3210 // clearing the mode bit around call sites). The mode bit is only used
3211 // if the relative frequency of single FP ops to calls is low enough.
3212 // This is a key transform for SPEC mpeg_audio.
3213 // (4) Detect infinite loops; blobs of code reachable from above but not
3214 // below. Several of the Code_Gen algorithms fail on such code shapes,
3215 // so we simply bail out. Happens a lot in ZKM.jar, but also happens
3216 // from time to time in other codes (such as -Xcomp finalizer loops, etc).
3217 // Detection is by looking for IfNodes where only 1 projection is
3218 // reachable from below or CatchNodes missing some targets.
3219 // (5) Assert for insane oop offsets in debug mode.
3220
3221 bool Compile::final_graph_reshaping() {
3222 // an infinite loop may have been eliminated by the optimizer,
3223 // in which case the graph will be empty.
3224 if (root()->req() == 1) {
3225 record_method_not_compilable("trivial infinite loop");
3226 return true;
3227 }
3228
3229 // Expensive nodes have their control input set to prevent the GVN
3230 // from freely commoning them. There's no GVN beyond this point so
3231 // no need to keep the control input. We want the expensive nodes to
3232 // be freely moved to the least frequent code path by gcm.
3233 assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
3234 for (int i = 0; i < expensive_count(); i++) {
3235 _expensive_nodes->at(i)->set_req(0, NULL);
3236 }
3237
3238 Final_Reshape_Counts frc;
3239
3240 // Visit everybody reachable!
3241 // Allocate stack of size C->unique()/2 to avoid frequent realloc
3242 Node_Stack nstack(unique() >> 1);
3243 final_graph_reshaping_walk(nstack, root(), frc);
3244
3245 // Check for unreachable (from below) code (i.e., infinite loops).
3246 for( uint i = 0; i < frc._tests.size(); i++ ) {
3247 MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
3248 // Get number of CFG targets.
3249 // Note that PCTables include exception targets after calls.
3250 uint required_outcnt = n->required_outcnt();
3251 if (n->outcnt() != required_outcnt) {
3252 // Check for a few special cases. Rethrow Nodes never take the
3253 // 'fall-thru' path, so expected kids is 1 less.
3254 if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
3255 if (n->in(0)->in(0)->is_Call()) {
3256 CallNode *call = n->in(0)->in(0)->as_Call();
3257 if (call->entry_point() == OptoRuntime::rethrow_stub()) {
3258 required_outcnt--; // Rethrow always has 1 less kid
3259 } else if (call->req() > TypeFunc::Parms &&
3260 call->is_CallDynamicJava()) {
3261 // Check for null receiver. In such case, the optimizer has
3262 // detected that the virtual call will always result in a null
3263 // pointer exception. The fall-through projection of this CatchNode
3264 // will not be populated.
3265 Node *arg0 = call->in(TypeFunc::Parms);
3266 if (arg0->is_Type() &&
3267 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
3268 required_outcnt--;
3269 }
3270 } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
3271 call->req() > TypeFunc::Parms+1 &&
3272 call->is_CallStaticJava()) {
3273 // Check for negative array length. In such case, the optimizer has
3274 // detected that the allocation attempt will always result in an
3275 // exception. There is no fall-through projection of this CatchNode .
3276 Node *arg1 = call->in(TypeFunc::Parms+1);
3277 if (arg1->is_Type() &&
3278 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
3279 required_outcnt--;
3280 }
3281 }
3282 }
3283 }
3284 // Recheck with a better notion of 'required_outcnt'
3285 if (n->outcnt() != required_outcnt) {
3286 record_method_not_compilable("malformed control flow");
3287 return true; // Not all targets reachable!
3288 }
3289 }
3290 // Check that I actually visited all kids. Unreached kids
3291 // must be infinite loops.
3292 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
3293 if (!frc._visited.test(n->fast_out(j)->_idx)) {
3294 record_method_not_compilable("infinite loop");
3295 return true; // Found unvisited kid; must be unreach
3296 }
3297 }
3298
3299 // If original bytecodes contained a mixture of floats and doubles
3300 // check if the optimizer has made it homogenous, item (3).
3301 if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
3302 frc.get_float_count() > 32 &&
3303 frc.get_double_count() == 0 &&
3304 (10 * frc.get_call_count() < frc.get_float_count()) ) {
3305 set_24_bit_selection_and_mode( false, true );
3306 }
3307
3308 set_java_calls(frc.get_java_call_count());
3309 set_inner_loops(frc.get_inner_loop_count());
3310
3311 // No infinite loops, no reason to bail out.
3312 return false;
3313 }
3314
3315 //-----------------------------too_many_traps----------------------------------
3316 // Report if there are too many traps at the current method and bci.
3317 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
3318 bool Compile::too_many_traps(ciMethod* method,
3319 int bci,
3320 Deoptimization::DeoptReason reason) {
3321 ciMethodData* md = method->method_data();
3322 if (md->is_empty()) {
3323 // Assume the trap has not occurred, or that it occurred only
3324 // because of a transient condition during start-up in the interpreter.
3325 return false;
3326 }
3327 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3328 if (md->has_trap_at(bci, m, reason) != 0) {
3329 // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
3330 // Also, if there are multiple reasons, or if there is no per-BCI record,
3331 // assume the worst.
3332 if (log())
3333 log()->elem("observe trap='%s' count='%d'",
3334 Deoptimization::trap_reason_name(reason),
3335 md->trap_count(reason));
3336 return true;
3337 } else {
3338 // Ignore method/bci and see if there have been too many globally.
3339 return too_many_traps(reason, md);
3340 }
3341 }
3342
3343 // Less-accurate variant which does not require a method and bci.
3344 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
3345 ciMethodData* logmd) {
3346 if (trap_count(reason) >= Deoptimization::per_method_trap_limit(reason)) {
3347 // Too many traps globally.
3348 // Note that we use cumulative trap_count, not just md->trap_count.
3349 if (log()) {
3350 int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
3351 log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
3352 Deoptimization::trap_reason_name(reason),
3353 mcount, trap_count(reason));
3354 }
3355 return true;
3356 } else {
3357 // The coast is clear.
3358 return false;
3359 }
3360 }
3361
3362 //--------------------------too_many_recompiles--------------------------------
3363 // Report if there are too many recompiles at the current method and bci.
3364 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
3365 // Is not eager to return true, since this will cause the compiler to use
3366 // Action_none for a trap point, to avoid too many recompilations.
3367 bool Compile::too_many_recompiles(ciMethod* method,
3368 int bci,
3369 Deoptimization::DeoptReason reason) {
3370 ciMethodData* md = method->method_data();
3371 if (md->is_empty()) {
3372 // Assume the trap has not occurred, or that it occurred only
3373 // because of a transient condition during start-up in the interpreter.
3374 return false;
3375 }
3376 // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
3377 uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
3378 uint m_cutoff = (uint) PerMethodRecompilationCutoff / 2 + 1; // not zero
3379 Deoptimization::DeoptReason per_bc_reason
3380 = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
3381 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3382 if ((per_bc_reason == Deoptimization::Reason_none
3383 || md->has_trap_at(bci, m, reason) != 0)
3384 // The trap frequency measure we care about is the recompile count:
3385 && md->trap_recompiled_at(bci, m)
3386 && md->overflow_recompile_count() >= bc_cutoff) {
3387 // Do not emit a trap here if it has already caused recompilations.
3388 // Also, if there are multiple reasons, or if there is no per-BCI record,
3389 // assume the worst.
3390 if (log())
3391 log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
3392 Deoptimization::trap_reason_name(reason),
3393 md->trap_count(reason),
3394 md->overflow_recompile_count());
3395 return true;
3396 } else if (trap_count(reason) != 0
3397 && decompile_count() >= m_cutoff) {
3398 // Too many recompiles globally, and we have seen this sort of trap.
3399 // Use cumulative decompile_count, not just md->decompile_count.
3400 if (log())
3401 log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
3402 Deoptimization::trap_reason_name(reason),
3403 md->trap_count(reason), trap_count(reason),
3404 md->decompile_count(), decompile_count());
3405 return true;
3406 } else {
3407 // The coast is clear.
3408 return false;
3409 }
3410 }
3411
3412 // Compute when not to trap. Used by matching trap based nodes and
3413 // NullCheck optimization.
3414 void Compile::set_allowed_deopt_reasons() {
3415 _allowed_reasons = 0;
3416 if (is_method_compilation()) {
3417 for (int rs = (int)Deoptimization::Reason_none+1; rs < Compile::trapHistLength; rs++) {
3418 assert(rs < BitsPerInt, "recode bit map");
3419 if (!too_many_traps((Deoptimization::DeoptReason) rs)) {
3420 _allowed_reasons |= nth_bit(rs);
3421 }
3422 }
3423 }
3424 }
3425
3426 #ifndef PRODUCT
3427 //------------------------------verify_graph_edges---------------------------
3428 // Walk the Graph and verify that there is a one-to-one correspondence
3429 // between Use-Def edges and Def-Use edges in the graph.
3430 void Compile::verify_graph_edges(bool no_dead_code) {
3431 if (VerifyGraphEdges) {
3432 ResourceArea *area = Thread::current()->resource_area();
3433 Unique_Node_List visited(area);
3434 // Call recursive graph walk to check edges
3435 _root->verify_edges(visited);
3436 if (no_dead_code) {
3437 // Now make sure that no visited node is used by an unvisited node.
3438 bool dead_nodes = false;
3439 Unique_Node_List checked(area);
3440 while (visited.size() > 0) {
3441 Node* n = visited.pop();
3442 checked.push(n);
3443 for (uint i = 0; i < n->outcnt(); i++) {
3444 Node* use = n->raw_out(i);
3445 if (checked.member(use)) continue; // already checked
3446 if (visited.member(use)) continue; // already in the graph
3447 if (use->is_Con()) continue; // a dead ConNode is OK
3448 // At this point, we have found a dead node which is DU-reachable.
3449 if (!dead_nodes) {
3450 tty->print_cr("*** Dead nodes reachable via DU edges:");
3451 dead_nodes = true;
3452 }
3453 use->dump(2);
3454 tty->print_cr("---");
3455 checked.push(use); // No repeats; pretend it is now checked.
3456 }
3457 }
3458 assert(!dead_nodes, "using nodes must be reachable from root");
3459 }
3460 }
3461 }
3462
3463 // Verify GC barriers consistency
3464 // Currently supported:
3465 // - G1 pre-barriers (see GraphKit::g1_write_barrier_pre())
3466 void Compile::verify_barriers() {
3467 if (UseG1GC) {
3468 // Verify G1 pre-barriers
3469 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + PtrQueue::byte_offset_of_active());
3470
3471 ResourceArea *area = Thread::current()->resource_area();
3472 Unique_Node_List visited(area);
3473 Node_List worklist(area);
3474 // We're going to walk control flow backwards starting from the Root
3475 worklist.push(_root);
3476 while (worklist.size() > 0) {
3477 Node* x = worklist.pop();
3478 if (x == NULL || x == top()) continue;
3479 if (visited.member(x)) {
3480 continue;
3481 } else {
3482 visited.push(x);
3483 }
3484
3485 if (x->is_Region()) {
3486 for (uint i = 1; i < x->req(); i++) {
3487 worklist.push(x->in(i));
3488 }
3489 } else {
3490 worklist.push(x->in(0));
3491 // We are looking for the pattern:
3492 // /->ThreadLocal
3493 // If->Bool->CmpI->LoadB->AddP->ConL(marking_offset)
3494 // \->ConI(0)
3495 // We want to verify that the If and the LoadB have the same control
3496 // See GraphKit::g1_write_barrier_pre()
3497 if (x->is_If()) {
3498 IfNode *iff = x->as_If();
3499 if (iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) {
3500 CmpNode *cmp = iff->in(1)->in(1)->as_Cmp();
3501 if (cmp->Opcode() == Op_CmpI && cmp->in(2)->is_Con() && cmp->in(2)->bottom_type()->is_int()->get_con() == 0
3502 && cmp->in(1)->is_Load()) {
3503 LoadNode* load = cmp->in(1)->as_Load();
3504 if (load->Opcode() == Op_LoadB && load->in(2)->is_AddP() && load->in(2)->in(2)->Opcode() == Op_ThreadLocal
3505 && load->in(2)->in(3)->is_Con()
3506 && load->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == marking_offset) {
3507
3508 Node* if_ctrl = iff->in(0);
3509 Node* load_ctrl = load->in(0);
3510
3511 if (if_ctrl != load_ctrl) {
3512 // Skip possible CProj->NeverBranch in infinite loops
3513 if ((if_ctrl->is_Proj() && if_ctrl->Opcode() == Op_CProj)
3514 && (if_ctrl->in(0)->is_MultiBranch() && if_ctrl->in(0)->Opcode() == Op_NeverBranch)) {
3515 if_ctrl = if_ctrl->in(0)->in(0);
3516 }
3517 }
3518 assert(load_ctrl != NULL && if_ctrl == load_ctrl, "controls must match");
3519 }
3520 }
3521 }
3522 }
3523 }
3524 }
3525 }
3526 }
3527
3528 #endif
3529
3530 // The Compile object keeps track of failure reasons separately from the ciEnv.
3531 // This is required because there is not quite a 1-1 relation between the
3532 // ciEnv and its compilation task and the Compile object. Note that one
3533 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
3534 // to backtrack and retry without subsuming loads. Other than this backtracking
3535 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
3536 // by the logic in C2Compiler.
3537 void Compile::record_failure(const char* reason) {
3538 if (log() != NULL) {
3539 log()->elem("failure reason='%s' phase='compile'", reason);
3540 }
3541 if (_failure_reason == NULL) {
3542 // Record the first failure reason.
3543 _failure_reason = reason;
3544 }
3545
3546 EventCompilerFailure event;
3547 if (event.should_commit()) {
3548 event.set_compileID(Compile::compile_id());
3549 event.set_failure(reason);
3550 event.commit();
3551 }
3552
3553 if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
3554 C->print_method(PHASE_FAILURE);
3555 }
3556 _root = NULL; // flush the graph, too
3557 }
3558
3559 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator)
3560 : TraceTime(name, accumulator, CITime, CITimeVerbose),
3561 _phase_name(name), _dolog(CITimeVerbose)
3562 {
3563 if (_dolog) {
3564 C = Compile::current();
3565 _log = C->log();
3566 } else {
3567 C = NULL;
3568 _log = NULL;
3569 }
3570 if (_log != NULL) {
3571 _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3572 _log->stamp();
3573 _log->end_head();
3574 }
3575 }
3576
3577 Compile::TracePhase::~TracePhase() {
3578
3579 C = Compile::current();
3580 if (_dolog) {
3581 _log = C->log();
3582 } else {
3583 _log = NULL;
3584 }
3585
3586 #ifdef ASSERT
3587 if (PrintIdealNodeCount) {
3588 tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
3589 _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
3590 }
3591
3592 if (VerifyIdealNodeCount) {
3593 Compile::current()->print_missing_nodes();
3594 }
3595 #endif
3596
3597 if (_log != NULL) {
3598 _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3599 }
3600 }
3601
3602 //=============================================================================
3603 // Two Constant's are equal when the type and the value are equal.
3604 bool Compile::Constant::operator==(const Constant& other) {
3605 if (type() != other.type() ) return false;
3606 if (can_be_reused() != other.can_be_reused()) return false;
3607 // For floating point values we compare the bit pattern.
3608 switch (type()) {
3609 case T_FLOAT: return (_v._value.i == other._v._value.i);
3610 case T_LONG:
3611 case T_DOUBLE: return (_v._value.j == other._v._value.j);
3612 case T_OBJECT:
3613 case T_ADDRESS: return (_v._value.l == other._v._value.l);
3614 case T_VOID: return (_v._value.l == other._v._value.l); // jump-table entries
3615 case T_METADATA: return (_v._metadata == other._v._metadata);
3616 default: ShouldNotReachHere();
3617 }
3618 return false;
3619 }
3620
3621 static int type_to_size_in_bytes(BasicType t) {
3622 switch (t) {
3623 case T_LONG: return sizeof(jlong );
3624 case T_FLOAT: return sizeof(jfloat );
3625 case T_DOUBLE: return sizeof(jdouble);
3626 case T_METADATA: return sizeof(Metadata*);
3627 // We use T_VOID as marker for jump-table entries (labels) which
3628 // need an internal word relocation.
3629 case T_VOID:
3630 case T_ADDRESS:
3631 case T_OBJECT: return sizeof(jobject);
3632 }
3633
3634 ShouldNotReachHere();
3635 return -1;
3636 }
3637
3638 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
3639 // sort descending
3640 if (a->freq() > b->freq()) return -1;
3641 if (a->freq() < b->freq()) return 1;
3642 return 0;
3643 }
3644
3645 void Compile::ConstantTable::calculate_offsets_and_size() {
3646 // First, sort the array by frequencies.
3647 _constants.sort(qsort_comparator);
3648
3649 #ifdef ASSERT
3650 // Make sure all jump-table entries were sorted to the end of the
3651 // array (they have a negative frequency).
3652 bool found_void = false;
3653 for (int i = 0; i < _constants.length(); i++) {
3654 Constant con = _constants.at(i);
3655 if (con.type() == T_VOID)
3656 found_void = true; // jump-tables
3657 else
3658 assert(!found_void, "wrong sorting");
3659 }
3660 #endif
3661
3662 int offset = 0;
3663 for (int i = 0; i < _constants.length(); i++) {
3664 Constant* con = _constants.adr_at(i);
3665
3666 // Align offset for type.
3667 int typesize = type_to_size_in_bytes(con->type());
3668 offset = align_size_up(offset, typesize);
3669 con->set_offset(offset); // set constant's offset
3670
3671 if (con->type() == T_VOID) {
3672 MachConstantNode* n = (MachConstantNode*) con->get_jobject();
3673 offset = offset + typesize * n->outcnt(); // expand jump-table
3674 } else {
3675 offset = offset + typesize;
3676 }
3677 }
3678
3679 // Align size up to the next section start (which is insts; see
3680 // CodeBuffer::align_at_start).
3681 assert(_size == -1, "already set?");
3682 _size = align_size_up(offset, CodeEntryAlignment);
3683 }
3684
3685 void Compile::ConstantTable::emit(CodeBuffer& cb) {
3686 MacroAssembler _masm(&cb);
3687 for (int i = 0; i < _constants.length(); i++) {
3688 Constant con = _constants.at(i);
3689 address constant_addr;
3690 switch (con.type()) {
3691 case T_LONG: constant_addr = _masm.long_constant( con.get_jlong() ); break;
3692 case T_FLOAT: constant_addr = _masm.float_constant( con.get_jfloat() ); break;
3693 case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
3694 case T_OBJECT: {
3695 jobject obj = con.get_jobject();
3696 int oop_index = _masm.oop_recorder()->find_index(obj);
3697 constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
3698 break;
3699 }
3700 case T_ADDRESS: {
3701 address addr = (address) con.get_jobject();
3702 constant_addr = _masm.address_constant(addr);
3703 break;
3704 }
3705 // We use T_VOID as marker for jump-table entries (labels) which
3706 // need an internal word relocation.
3707 case T_VOID: {
3708 MachConstantNode* n = (MachConstantNode*) con.get_jobject();
3709 // Fill the jump-table with a dummy word. The real value is
3710 // filled in later in fill_jump_table.
3711 address dummy = (address) n;
3712 constant_addr = _masm.address_constant(dummy);
3713 // Expand jump-table
3714 for (uint i = 1; i < n->outcnt(); i++) {
3715 address temp_addr = _masm.address_constant(dummy + i);
3716 assert(temp_addr, "consts section too small");
3717 }
3718 break;
3719 }
3720 case T_METADATA: {
3721 Metadata* obj = con.get_metadata();
3722 int metadata_index = _masm.oop_recorder()->find_index(obj);
3723 constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
3724 break;
3725 }
3726 default: ShouldNotReachHere();
3727 }
3728 assert(constant_addr, "consts section too small");
3729 assert((constant_addr - _masm.code()->consts()->start()) == con.offset(),
3730 err_msg_res("must be: %d == %d", (int) (constant_addr - _masm.code()->consts()->start()), (int)(con.offset())));
3731 }
3732 }
3733
3734 int Compile::ConstantTable::find_offset(Constant& con) const {
3735 int idx = _constants.find(con);
3736 assert(idx != -1, "constant must be in constant table");
3737 int offset = _constants.at(idx).offset();
3738 assert(offset != -1, "constant table not emitted yet?");
3739 return offset;
3740 }
3741
3742 void Compile::ConstantTable::add(Constant& con) {
3743 if (con.can_be_reused()) {
3744 int idx = _constants.find(con);
3745 if (idx != -1 && _constants.at(idx).can_be_reused()) {
3746 _constants.adr_at(idx)->inc_freq(con.freq()); // increase the frequency by the current value
3747 return;
3748 }
3749 }
3750 (void) _constants.append(con);
3751 }
3752
3753 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
3754 Block* b = Compile::current()->cfg()->get_block_for_node(n);
3755 Constant con(type, value, b->_freq);
3756 add(con);
3757 return con;
3758 }
3759
3760 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
3761 Constant con(metadata);
3762 add(con);
3763 return con;
3764 }
3765
3766 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
3767 jvalue value;
3768 BasicType type = oper->type()->basic_type();
3769 switch (type) {
3770 case T_LONG: value.j = oper->constantL(); break;
3771 case T_FLOAT: value.f = oper->constantF(); break;
3772 case T_DOUBLE: value.d = oper->constantD(); break;
3773 case T_OBJECT:
3774 case T_ADDRESS: value.l = (jobject) oper->constant(); break;
3775 case T_METADATA: return add((Metadata*)oper->constant()); break;
3776 default: guarantee(false, err_msg_res("unhandled type: %s", type2name(type)));
3777 }
3778 return add(n, type, value);
3779 }
3780
3781 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
3782 jvalue value;
3783 // We can use the node pointer here to identify the right jump-table
3784 // as this method is called from Compile::Fill_buffer right before
3785 // the MachNodes are emitted and the jump-table is filled (means the
3786 // MachNode pointers do not change anymore).
3787 value.l = (jobject) n;
3788 Constant con(T_VOID, value, next_jump_table_freq(), false); // Labels of a jump-table cannot be reused.
3789 add(con);
3790 return con;
3791 }
3792
3793 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
3794 // If called from Compile::scratch_emit_size do nothing.
3795 if (Compile::current()->in_scratch_emit_size()) return;
3796
3797 assert(labels.is_nonempty(), "must be");
3798 assert((uint) labels.length() == n->outcnt(), err_msg_res("must be equal: %d == %d", labels.length(), n->outcnt()));
3799
3800 // Since MachConstantNode::constant_offset() also contains
3801 // table_base_offset() we need to subtract the table_base_offset()
3802 // to get the plain offset into the constant table.
3803 int offset = n->constant_offset() - table_base_offset();
3804
3805 MacroAssembler _masm(&cb);
3806 address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
3807
3808 for (uint i = 0; i < n->outcnt(); i++) {
3809 address* constant_addr = &jump_table_base[i];
3810 assert(*constant_addr == (((address) n) + i), err_msg_res("all jump-table entries must contain adjusted node pointer: " INTPTR_FORMAT " == " INTPTR_FORMAT, p2i(*constant_addr), p2i(((address) n) + i)));
3811 *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
3812 cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
3813 }
3814 }
3815
3816 //----------------------------static_subtype_check-----------------------------
3817 // Shortcut important common cases when superklass is exact:
3818 // (0) superklass is java.lang.Object (can occur in reflective code)
3819 // (1) subklass is already limited to a subtype of superklass => always ok
3820 // (2) subklass does not overlap with superklass => always fail
3821 // (3) superklass has NO subtypes and we can check with a simple compare.
3822 int Compile::static_subtype_check(ciKlass* superk, ciKlass* subk) {
3823 if (StressReflectiveCode) {
3824 return SSC_full_test; // Let caller generate the general case.
3825 }
3826
3827 if (superk == env()->Object_klass()) {
3828 return SSC_always_true; // (0) this test cannot fail
3829 }
3830
3831 ciType* superelem = superk;
3832 if (superelem->is_array_klass())
3833 superelem = superelem->as_array_klass()->base_element_type();
3834
3835 if (!subk->is_interface()) { // cannot trust static interface types yet
3836 if (subk->is_subtype_of(superk)) {
3837 return SSC_always_true; // (1) false path dead; no dynamic test needed
3838 }
3839 if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
3840 !superk->is_subtype_of(subk)) {
3841 return SSC_always_false;
3842 }
3843 }
3844
3845 // If casting to an instance klass, it must have no subtypes
3846 if (superk->is_interface()) {
3847 // Cannot trust interfaces yet.
3848 // %%% S.B. superk->nof_implementors() == 1
3849 } else if (superelem->is_instance_klass()) {
3850 ciInstanceKlass* ik = superelem->as_instance_klass();
3851 if (!ik->has_subklass() && !ik->is_interface()) {
3852 if (!ik->is_final()) {
3853 // Add a dependency if there is a chance of a later subclass.
3854 dependencies()->assert_leaf_type(ik);
3855 }
3856 return SSC_easy_test; // (3) caller can do a simple ptr comparison
3857 }
3858 } else {
3859 // A primitive array type has no subtypes.
3860 return SSC_easy_test; // (3) caller can do a simple ptr comparison
3861 }
3862
3863 return SSC_full_test;
3864 }
3865
3866 // The message about the current inlining is accumulated in
3867 // _print_inlining_stream and transfered into the _print_inlining_list
3868 // once we know whether inlining succeeds or not. For regular
3869 // inlining, messages are appended to the buffer pointed by
3870 // _print_inlining_idx in the _print_inlining_list. For late inlining,
3871 // a new buffer is added after _print_inlining_idx in the list. This
3872 // way we can update the inlining message for late inlining call site
3873 // when the inlining is attempted again.
3874 void Compile::print_inlining_init() {
3875 if (print_inlining() || print_intrinsics()) {
3876 _print_inlining_stream = new stringStream();
3877 _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
3878 }
3879 }
3880
3881 void Compile::print_inlining_reinit() {
3882 if (print_inlining() || print_intrinsics()) {
3883 // Re allocate buffer when we change ResourceMark
3884 _print_inlining_stream = new stringStream();
3885 }
3886 }
3887
3888 void Compile::print_inlining_reset() {
3889 _print_inlining_stream->reset();
3890 }
3891
3892 void Compile::print_inlining_commit() {
3893 assert(print_inlining() || print_intrinsics(), "PrintInlining off?");
3894 // Transfer the message from _print_inlining_stream to the current
3895 // _print_inlining_list buffer and clear _print_inlining_stream.
3896 _print_inlining_list->at(_print_inlining_idx).ss()->write(_print_inlining_stream->as_string(), _print_inlining_stream->size());
3897 print_inlining_reset();
3898 }
3899
3900 void Compile::print_inlining_push() {
3901 // Add new buffer to the _print_inlining_list at current position
3902 _print_inlining_idx++;
3903 _print_inlining_list->insert_before(_print_inlining_idx, PrintInliningBuffer());
3904 }
3905
3906 Compile::PrintInliningBuffer& Compile::print_inlining_current() {
3907 return _print_inlining_list->at(_print_inlining_idx);
3908 }
3909
3910 void Compile::print_inlining_update(CallGenerator* cg) {
3911 if (print_inlining() || print_intrinsics()) {
3912 if (!cg->is_late_inline()) {
3913 if (print_inlining_current().cg() != NULL) {
3914 print_inlining_push();
3915 }
3916 print_inlining_commit();
3917 } else {
3918 if (print_inlining_current().cg() != cg &&
3919 (print_inlining_current().cg() != NULL ||
3920 print_inlining_current().ss()->size() != 0)) {
3921 print_inlining_push();
3922 }
3923 print_inlining_commit();
3924 print_inlining_current().set_cg(cg);
3925 }
3926 }
3927 }
3928
3929 void Compile::print_inlining_move_to(CallGenerator* cg) {
3930 // We resume inlining at a late inlining call site. Locate the
3931 // corresponding inlining buffer so that we can update it.
3932 if (print_inlining()) {
3933 for (int i = 0; i < _print_inlining_list->length(); i++) {
3934 if (_print_inlining_list->adr_at(i)->cg() == cg) {
3935 _print_inlining_idx = i;
3936 return;
3937 }
3938 }
3939 ShouldNotReachHere();
3940 }
3941 }
3942
3943 void Compile::print_inlining_update_delayed(CallGenerator* cg) {
3944 if (print_inlining()) {
3945 assert(_print_inlining_stream->size() > 0, "missing inlining msg");
3946 assert(print_inlining_current().cg() == cg, "wrong entry");
3947 // replace message with new message
3948 _print_inlining_list->at_put(_print_inlining_idx, PrintInliningBuffer());
3949 print_inlining_commit();
3950 print_inlining_current().set_cg(cg);
3951 }
3952 }
3953
3954 void Compile::print_inlining_assert_ready() {
3955 assert(!_print_inlining || _print_inlining_stream->size() == 0, "loosing data");
3956 }
3957
3958 void Compile::process_print_inlining() {
3959 bool do_print_inlining = print_inlining() || print_intrinsics();
3960 if (do_print_inlining || log() != NULL) {
3961 // Print inlining message for candidates that we couldn't inline
3962 // for lack of space
3963 for (int i = 0; i < _late_inlines.length(); i++) {
3964 CallGenerator* cg = _late_inlines.at(i);
3965 if (!cg->is_mh_late_inline()) {
3966 const char* msg = "live nodes > LiveNodeCountInliningCutoff";
3967 if (do_print_inlining) {
3968 cg->print_inlining_late(msg);
3969 }
3970 log_late_inline_failure(cg, msg);
3971 }
3972 }
3973 }
3974 if (do_print_inlining) {
3975 ResourceMark rm;
3976 stringStream ss;
3977 for (int i = 0; i < _print_inlining_list->length(); i++) {
3978 ss.print("%s", _print_inlining_list->adr_at(i)->ss()->as_string());
3979 }
3980 size_t end = ss.size();
3981 _print_inlining_output = NEW_ARENA_ARRAY(comp_arena(), char, end+1);
3982 strncpy(_print_inlining_output, ss.base(), end+1);
3983 _print_inlining_output[end] = 0;
3984 }
3985 }
3986
3987 void Compile::dump_print_inlining() {
3988 if (_print_inlining_output != NULL) {
3989 tty->print_raw(_print_inlining_output);
3990 }
3991 }
3992
3993 void Compile::log_late_inline(CallGenerator* cg) {
3994 if (log() != NULL) {
3995 log()->head("late_inline method='%d' inline_id='" JLONG_FORMAT "'", log()->identify(cg->method()),
3996 cg->unique_id());
3997 JVMState* p = cg->call_node()->jvms();
3998 while (p != NULL) {
3999 log()->elem("jvms bci='%d' method='%d'", p->bci(), log()->identify(p->method()));
4000 p = p->caller();
4001 }
4002 log()->tail("late_inline");
4003 }
4004 }
4005
4006 void Compile::log_late_inline_failure(CallGenerator* cg, const char* msg) {
4007 log_late_inline(cg);
4008 if (log() != NULL) {
4009 log()->inline_fail(msg);
4010 }
4011 }
4012
4013 void Compile::log_inline_id(CallGenerator* cg) {
4014 if (log() != NULL) {
4015 // The LogCompilation tool needs a unique way to identify late
4016 // inline call sites. This id must be unique for this call site in
4017 // this compilation. Try to have it unique across compilations as
4018 // well because it can be convenient when grepping through the log
4019 // file.
4020 // Distinguish OSR compilations from others in case CICountOSR is
4021 // on.
4022 jlong id = ((jlong)unique()) + (((jlong)compile_id()) << 33) + (CICountOSR && is_osr_compilation() ? ((jlong)1) << 32 : 0);
4023 cg->set_unique_id(id);
4024 log()->elem("inline_id id='" JLONG_FORMAT "'", id);
4025 }
4026 }
4027
4028 void Compile::log_inline_failure(const char* msg) {
4029 if (C->log() != NULL) {
4030 C->log()->inline_fail(msg);
4031 }
4032 }
4033
4034
4035 // Dump inlining replay data to the stream.
4036 // Don't change thread state and acquire any locks.
4037 void Compile::dump_inline_data(outputStream* out) {
4038 InlineTree* inl_tree = ilt();
4039 if (inl_tree != NULL) {
4040 out->print(" inline %d", inl_tree->count());
4041 inl_tree->dump_replay_data(out);
4042 }
4043 }
4044
4045 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
4046 if (n1->Opcode() < n2->Opcode()) return -1;
4047 else if (n1->Opcode() > n2->Opcode()) return 1;
4048
4049 assert(n1->req() == n2->req(), err_msg_res("can't compare %s nodes: n1->req() = %d, n2->req() = %d", NodeClassNames[n1->Opcode()], n1->req(), n2->req()));
4050 for (uint i = 1; i < n1->req(); i++) {
4051 if (n1->in(i) < n2->in(i)) return -1;
4052 else if (n1->in(i) > n2->in(i)) return 1;
4053 }
4054
4055 return 0;
4056 }
4057
4058 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
4059 Node* n1 = *n1p;
4060 Node* n2 = *n2p;
4061
4062 return cmp_expensive_nodes(n1, n2);
4063 }
4064
4065 void Compile::sort_expensive_nodes() {
4066 if (!expensive_nodes_sorted()) {
4067 _expensive_nodes->sort(cmp_expensive_nodes);
4068 }
4069 }
4070
4071 bool Compile::expensive_nodes_sorted() const {
4072 for (int i = 1; i < _expensive_nodes->length(); i++) {
4073 if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
4074 return false;
4075 }
4076 }
4077 return true;
4078 }
4079
4080 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
4081 if (_expensive_nodes->length() == 0) {
4082 return false;
4083 }
4084
4085 assert(OptimizeExpensiveOps, "optimization off?");
4086
4087 // Take this opportunity to remove dead nodes from the list
4088 int j = 0;
4089 for (int i = 0; i < _expensive_nodes->length(); i++) {
4090 Node* n = _expensive_nodes->at(i);
4091 if (!n->is_unreachable(igvn)) {
4092 assert(n->is_expensive(), "should be expensive");
4093 _expensive_nodes->at_put(j, n);
4094 j++;
4095 }
4096 }
4097 _expensive_nodes->trunc_to(j);
4098
4099 // Then sort the list so that similar nodes are next to each other
4100 // and check for at least two nodes of identical kind with same data
4101 // inputs.
4102 sort_expensive_nodes();
4103
4104 for (int i = 0; i < _expensive_nodes->length()-1; i++) {
4105 if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
4106 return true;
4107 }
4108 }
4109
4110 return false;
4111 }
4112
4113 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
4114 if (_expensive_nodes->length() == 0) {
4115 return;
4116 }
4117
4118 assert(OptimizeExpensiveOps, "optimization off?");
4119
4120 // Sort to bring similar nodes next to each other and clear the
4121 // control input of nodes for which there's only a single copy.
4122 sort_expensive_nodes();
4123
4124 int j = 0;
4125 int identical = 0;
4126 int i = 0;
4127 bool modified = false;
4128 for (; i < _expensive_nodes->length()-1; i++) {
4129 assert(j <= i, "can't write beyond current index");
4130 if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
4131 identical++;
4132 _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4133 continue;
4134 }
4135 if (identical > 0) {
4136 _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4137 identical = 0;
4138 } else {
4139 Node* n = _expensive_nodes->at(i);
4140 igvn.replace_input_of(n, 0, NULL);
4141 igvn.hash_insert(n);
4142 modified = true;
4143 }
4144 }
4145 if (identical > 0) {
4146 _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4147 } else if (_expensive_nodes->length() >= 1) {
4148 Node* n = _expensive_nodes->at(i);
4149 igvn.replace_input_of(n, 0, NULL);
4150 igvn.hash_insert(n);
4151 modified = true;
4152 }
4153 _expensive_nodes->trunc_to(j);
4154 if (modified) {
4155 igvn.optimize();
4156 }
4157 }
4158
4159 void Compile::add_expensive_node(Node * n) {
4160 assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
4161 assert(n->is_expensive(), "expensive nodes with non-null control here only");
4162 assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
4163 if (OptimizeExpensiveOps) {
4164 _expensive_nodes->append(n);
4165 } else {
4166 // Clear control input and let IGVN optimize expensive nodes if
4167 // OptimizeExpensiveOps is off.
4168 n->set_req(0, NULL);
4169 }
4170 }
4171
4172 /**
4173 * Remove the speculative part of types and clean up the graph
4174 */
4175 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
4176 if (UseTypeSpeculation) {
4177 Unique_Node_List worklist;
4178 worklist.push(root());
4179 int modified = 0;
4180 // Go over all type nodes that carry a speculative type, drop the
4181 // speculative part of the type and enqueue the node for an igvn
4182 // which may optimize it out.
4183 for (uint next = 0; next < worklist.size(); ++next) {
4184 Node *n = worklist.at(next);
4185 if (n->is_Type()) {
4186 TypeNode* tn = n->as_Type();
4187 const Type* t = tn->type();
4188 const Type* t_no_spec = t->remove_speculative();
4189 if (t_no_spec != t) {
4190 bool in_hash = igvn.hash_delete(n);
4191 assert(in_hash, "node should be in igvn hash table");
4192 tn->set_type(t_no_spec);
4193 igvn.hash_insert(n);
4194 igvn._worklist.push(n); // give it a chance to go away
4195 modified++;
4196 }
4197 }
4198 uint max = n->len();
4199 for( uint i = 0; i < max; ++i ) {
4200 Node *m = n->in(i);
4201 if (not_a_node(m)) continue;
4202 worklist.push(m);
4203 }
4204 }
4205 // Drop the speculative part of all types in the igvn's type table
4206 igvn.remove_speculative_types();
4207 if (modified > 0) {
4208 igvn.optimize();
4209 }
4210 #ifdef ASSERT
4211 // Verify that after the IGVN is over no speculative type has resurfaced
4212 worklist.clear();
4213 worklist.push(root());
4214 for (uint next = 0; next < worklist.size(); ++next) {
4215 Node *n = worklist.at(next);
4216 const Type* t = igvn.type_or_null(n);
4217 assert((t == NULL) || (t == t->remove_speculative()), "no more speculative types");
4218 if (n->is_Type()) {
4219 t = n->as_Type()->type();
4220 assert(t == t->remove_speculative(), "no more speculative types");
4221 }
4222 uint max = n->len();
4223 for( uint i = 0; i < max; ++i ) {
4224 Node *m = n->in(i);
4225 if (not_a_node(m)) continue;
4226 worklist.push(m);
4227 }
4228 }
4229 igvn.check_no_speculative_types();
4230 #endif
4231 }
4232 }
4233
4234 // Auxiliary method to support randomized stressing/fuzzing.
4235 //
4236 // This method can be called the arbitrary number of times, with current count
4237 // as the argument. The logic allows selecting a single candidate from the
4238 // running list of candidates as follows:
4239 // int count = 0;
4240 // Cand* selected = null;
4241 // while(cand = cand->next()) {
4242 // if (randomized_select(++count)) {
4243 // selected = cand;
4244 // }
4245 // }
4246 //
4247 // Including count equalizes the chances any candidate is "selected".
4248 // This is useful when we don't have the complete list of candidates to choose
4249 // from uniformly. In this case, we need to adjust the randomicity of the
4250 // selection, or else we will end up biasing the selection towards the latter
4251 // candidates.
4252 //
4253 // Quick back-envelope calculation shows that for the list of n candidates
4254 // the equal probability for the candidate to persist as "best" can be
4255 // achieved by replacing it with "next" k-th candidate with the probability
4256 // of 1/k. It can be easily shown that by the end of the run, the
4257 // probability for any candidate is converged to 1/n, thus giving the
4258 // uniform distribution among all the candidates.
4259 //
4260 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
4261 #define RANDOMIZED_DOMAIN_POW 29
4262 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
4263 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
4264 bool Compile::randomized_select(int count) {
4265 assert(count > 0, "only positive");
4266 return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);
4267 }