1 /*
2 * Copyright (c) 1997, 2018, 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/compileLog.hpp"
33 #include "compiler/disassembler.hpp"
34 #include "compiler/oopMap.hpp"
35 #include "jfr/jfrEvents.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/node.hpp"
56 #include "opto/opcodes.hpp"
57 #include "opto/output.hpp"
58 #include "opto/parse.hpp"
59 #include "opto/phaseX.hpp"
60 #include "opto/rootnode.hpp"
61 #include "opto/runtime.hpp"
62 #include "opto/stringopts.hpp"
63 #include "opto/type.hpp"
64 #include "opto/vectornode.hpp"
65 #include "runtime/arguments.hpp"
66 #include "runtime/signature.hpp"
67 #include "runtime/stubRoutines.hpp"
68 #include "runtime/timer.hpp"
69 #include "utilities/copy.hpp"
70 #if defined AD_MD_HPP
71 # include AD_MD_HPP
72 #elif defined TARGET_ARCH_MODEL_x86_32
73 # include "adfiles/ad_x86_32.hpp"
74 #elif defined TARGET_ARCH_MODEL_x86_64
75 # include "adfiles/ad_x86_64.hpp"
76 #elif defined TARGET_ARCH_MODEL_aarch64
77 # include "adfiles/ad_aarch64.hpp"
78 #elif defined TARGET_ARCH_MODEL_sparc
79 # include "adfiles/ad_sparc.hpp"
80 #elif defined TARGET_ARCH_MODEL_zero
81 # include "adfiles/ad_zero.hpp"
82 #elif defined TARGET_ARCH_MODEL_ppc_64
83 # include "adfiles/ad_ppc_64.hpp"
84 #endif
85
86 // -------------------- Compile::mach_constant_base_node -----------------------
87 // Constant table base node singleton.
88 MachConstantBaseNode* Compile::mach_constant_base_node() {
89 if (_mach_constant_base_node == NULL) {
90 _mach_constant_base_node = new (C) MachConstantBaseNode();
91 _mach_constant_base_node->add_req(C->root());
92 }
93 return _mach_constant_base_node;
94 }
95
96
97 /// Support for intrinsics.
98
99 // Return the index at which m must be inserted (or already exists).
100 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
101 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual) {
102 #ifdef ASSERT
103 for (int i = 1; i < _intrinsics->length(); i++) {
104 CallGenerator* cg1 = _intrinsics->at(i-1);
105 CallGenerator* cg2 = _intrinsics->at(i);
106 assert(cg1->method() != cg2->method()
107 ? cg1->method() < cg2->method()
108 : cg1->is_virtual() < cg2->is_virtual(),
109 "compiler intrinsics list must stay sorted");
110 }
111 #endif
112 // Binary search sorted list, in decreasing intervals [lo, hi].
113 int lo = 0, hi = _intrinsics->length()-1;
114 while (lo <= hi) {
115 int mid = (uint)(hi + lo) / 2;
116 ciMethod* mid_m = _intrinsics->at(mid)->method();
117 if (m < mid_m) {
118 hi = mid-1;
119 } else if (m > mid_m) {
120 lo = mid+1;
121 } else {
122 // look at minor sort key
123 bool mid_virt = _intrinsics->at(mid)->is_virtual();
124 if (is_virtual < mid_virt) {
125 hi = mid-1;
126 } else if (is_virtual > mid_virt) {
127 lo = mid+1;
128 } else {
129 return mid; // exact match
130 }
131 }
132 }
133 return lo; // inexact match
134 }
135
136 void Compile::register_intrinsic(CallGenerator* cg) {
137 if (_intrinsics == NULL) {
138 _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
139 }
140 // This code is stolen from ciObjectFactory::insert.
141 // Really, GrowableArray should have methods for
142 // insert_at, remove_at, and binary_search.
143 int len = _intrinsics->length();
144 int index = intrinsic_insertion_index(cg->method(), cg->is_virtual());
145 if (index == len) {
146 _intrinsics->append(cg);
147 } else {
148 #ifdef ASSERT
149 CallGenerator* oldcg = _intrinsics->at(index);
150 assert(oldcg->method() != cg->method() || oldcg->is_virtual() != cg->is_virtual(), "don't register twice");
151 #endif
152 _intrinsics->append(_intrinsics->at(len-1));
153 int pos;
154 for (pos = len-2; pos >= index; pos--) {
155 _intrinsics->at_put(pos+1,_intrinsics->at(pos));
156 }
157 _intrinsics->at_put(index, cg);
158 }
159 assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
160 }
161
162 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
163 assert(m->is_loaded(), "don't try this on unloaded methods");
164 if (_intrinsics != NULL) {
165 int index = intrinsic_insertion_index(m, is_virtual);
166 if (index < _intrinsics->length()
167 && _intrinsics->at(index)->method() == m
168 && _intrinsics->at(index)->is_virtual() == is_virtual) {
169 return _intrinsics->at(index);
170 }
171 }
172 // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
173 if (m->intrinsic_id() != vmIntrinsics::_none &&
174 m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
175 CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
176 if (cg != NULL) {
177 // Save it for next time:
178 register_intrinsic(cg);
179 return cg;
180 } else {
181 gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
182 }
183 }
184 return NULL;
185 }
186
187 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
188 // in library_call.cpp.
189
190
191 #ifndef PRODUCT
192 // statistics gathering...
193
194 juint Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
195 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
196
197 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
198 assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
199 int oflags = _intrinsic_hist_flags[id];
200 assert(flags != 0, "what happened?");
201 if (is_virtual) {
202 flags |= _intrinsic_virtual;
203 }
204 bool changed = (flags != oflags);
205 if ((flags & _intrinsic_worked) != 0) {
206 juint count = (_intrinsic_hist_count[id] += 1);
207 if (count == 1) {
208 changed = true; // first time
209 }
210 // increment the overall count also:
211 _intrinsic_hist_count[vmIntrinsics::_none] += 1;
212 }
213 if (changed) {
214 if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
215 // Something changed about the intrinsic's virtuality.
216 if ((flags & _intrinsic_virtual) != 0) {
217 // This is the first use of this intrinsic as a virtual call.
218 if (oflags != 0) {
219 // We already saw it as a non-virtual, so note both cases.
220 flags |= _intrinsic_both;
221 }
222 } else if ((oflags & _intrinsic_both) == 0) {
223 // This is the first use of this intrinsic as a non-virtual
224 flags |= _intrinsic_both;
225 }
226 }
227 _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
228 }
229 // update the overall flags also:
230 _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
231 return changed;
232 }
233
234 static char* format_flags(int flags, char* buf) {
235 buf[0] = 0;
236 if ((flags & Compile::_intrinsic_worked) != 0) strcat(buf, ",worked");
237 if ((flags & Compile::_intrinsic_failed) != 0) strcat(buf, ",failed");
238 if ((flags & Compile::_intrinsic_disabled) != 0) strcat(buf, ",disabled");
239 if ((flags & Compile::_intrinsic_virtual) != 0) strcat(buf, ",virtual");
240 if ((flags & Compile::_intrinsic_both) != 0) strcat(buf, ",nonvirtual");
241 if (buf[0] == 0) strcat(buf, ",");
242 assert(buf[0] == ',', "must be");
243 return &buf[1];
244 }
245
246 void Compile::print_intrinsic_statistics() {
247 char flagsbuf[100];
248 ttyLocker ttyl;
249 if (xtty != NULL) xtty->head("statistics type='intrinsic'");
250 tty->print_cr("Compiler intrinsic usage:");
251 juint total = _intrinsic_hist_count[vmIntrinsics::_none];
252 if (total == 0) total = 1; // avoid div0 in case of no successes
253 #define PRINT_STAT_LINE(name, c, f) \
254 tty->print_cr(" %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
255 for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
256 vmIntrinsics::ID id = (vmIntrinsics::ID) index;
257 int flags = _intrinsic_hist_flags[id];
258 juint count = _intrinsic_hist_count[id];
259 if ((flags | count) != 0) {
260 PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
261 }
262 }
263 PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
264 if (xtty != NULL) xtty->tail("statistics");
265 }
266
267 void Compile::print_statistics() {
268 { ttyLocker ttyl;
269 if (xtty != NULL) xtty->head("statistics type='opto'");
270 Parse::print_statistics();
271 PhaseCCP::print_statistics();
272 PhaseRegAlloc::print_statistics();
273 Scheduling::print_statistics();
274 PhasePeephole::print_statistics();
275 PhaseIdealLoop::print_statistics();
276 if (xtty != NULL) xtty->tail("statistics");
277 }
278 if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
279 // put this under its own <statistics> element.
280 print_intrinsic_statistics();
281 }
282 }
283 #endif //PRODUCT
284
285 // Support for bundling info
286 Bundle* Compile::node_bundling(const Node *n) {
287 assert(valid_bundle_info(n), "oob");
288 return &_node_bundling_base[n->_idx];
289 }
290
291 bool Compile::valid_bundle_info(const Node *n) {
292 return (_node_bundling_limit > n->_idx);
293 }
294
295
296 void Compile::gvn_replace_by(Node* n, Node* nn) {
297 for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
298 Node* use = n->last_out(i);
299 bool is_in_table = initial_gvn()->hash_delete(use);
300 uint uses_found = 0;
301 for (uint j = 0; j < use->len(); j++) {
302 if (use->in(j) == n) {
303 if (j < use->req())
304 use->set_req(j, nn);
305 else
306 use->set_prec(j, nn);
307 uses_found++;
308 }
309 }
310 if (is_in_table) {
311 // reinsert into table
312 initial_gvn()->hash_find_insert(use);
313 }
314 record_for_igvn(use);
315 i -= uses_found; // we deleted 1 or more copies of this edge
316 }
317 }
318
319
320 static inline bool not_a_node(const Node* n) {
321 if (n == NULL) return true;
322 if (((intptr_t)n & 1) != 0) return true; // uninitialized, etc.
323 if (*(address*)n == badAddress) return true; // kill by Node::destruct
324 return false;
325 }
326
327 // Identify all nodes that are reachable from below, useful.
328 // Use breadth-first pass that records state in a Unique_Node_List,
329 // recursive traversal is slower.
330 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
331 int estimated_worklist_size = live_nodes();
332 useful.map( estimated_worklist_size, NULL ); // preallocate space
333
334 // Initialize worklist
335 if (root() != NULL) { useful.push(root()); }
336 // If 'top' is cached, declare it useful to preserve cached node
337 if( cached_top_node() ) { useful.push(cached_top_node()); }
338
339 // Push all useful nodes onto the list, breadthfirst
340 for( uint next = 0; next < useful.size(); ++next ) {
341 assert( next < unique(), "Unique useful nodes < total nodes");
342 Node *n = useful.at(next);
343 uint max = n->len();
344 for( uint i = 0; i < max; ++i ) {
345 Node *m = n->in(i);
346 if (not_a_node(m)) continue;
347 useful.push(m);
348 }
349 }
350 }
351
352 // Update dead_node_list with any missing dead nodes using useful
353 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
354 void Compile::update_dead_node_list(Unique_Node_List &useful) {
355 uint max_idx = unique();
356 VectorSet& useful_node_set = useful.member_set();
357
358 for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
359 // If node with index node_idx is not in useful set,
360 // mark it as dead in dead node list.
361 if (! useful_node_set.test(node_idx) ) {
362 record_dead_node(node_idx);
363 }
364 }
365 }
366
367 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
368 int shift = 0;
369 for (int i = 0; i < inlines->length(); i++) {
370 CallGenerator* cg = inlines->at(i);
371 CallNode* call = cg->call_node();
372 if (shift > 0) {
373 inlines->at_put(i-shift, cg);
374 }
375 if (!useful.member(call)) {
376 shift++;
377 }
378 }
379 inlines->trunc_to(inlines->length()-shift);
380 }
381
382 // Disconnect all useless nodes by disconnecting those at the boundary.
383 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
384 uint next = 0;
385 while (next < useful.size()) {
386 Node *n = useful.at(next++);
387 if (n->is_SafePoint()) {
388 // We're done with a parsing phase. Replaced nodes are not valid
389 // beyond that point.
390 n->as_SafePoint()->delete_replaced_nodes();
391 }
392 // Use raw traversal of out edges since this code removes out edges
393 int max = n->outcnt();
394 for (int j = 0; j < max; ++j) {
395 Node* child = n->raw_out(j);
396 if (! useful.member(child)) {
397 assert(!child->is_top() || child != top(),
398 "If top is cached in Compile object it is in useful list");
399 // Only need to remove this out-edge to the useless node
400 n->raw_del_out(j);
401 --j;
402 --max;
403 }
404 }
405 if (n->outcnt() == 1 && n->has_special_unique_user()) {
406 record_for_igvn(n->unique_out());
407 }
408 }
409 // Remove useless macro and predicate opaq nodes
410 for (int i = C->macro_count()-1; i >= 0; i--) {
411 Node* n = C->macro_node(i);
412 if (!useful.member(n)) {
413 remove_macro_node(n);
414 }
415 }
416 // Remove useless CastII nodes with range check dependency
417 for (int i = range_check_cast_count() - 1; i >= 0; i--) {
418 Node* cast = range_check_cast_node(i);
419 if (!useful.member(cast)) {
420 remove_range_check_cast(cast);
421 }
422 }
423 // Remove useless expensive node
424 for (int i = C->expensive_count()-1; i >= 0; i--) {
425 Node* n = C->expensive_node(i);
426 if (!useful.member(n)) {
427 remove_expensive_node(n);
428 }
429 }
430 // clean up the late inline lists
431 remove_useless_late_inlines(&_string_late_inlines, useful);
432 remove_useless_late_inlines(&_boxing_late_inlines, useful);
433 remove_useless_late_inlines(&_late_inlines, useful);
434 debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
435 }
436
437 //------------------------------frame_size_in_words-----------------------------
438 // frame_slots in units of words
439 int Compile::frame_size_in_words() const {
440 // shift is 0 in LP32 and 1 in LP64
441 const int shift = (LogBytesPerWord - LogBytesPerInt);
442 int words = _frame_slots >> shift;
443 assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
444 return words;
445 }
446
447 // To bang the stack of this compiled method we use the stack size
448 // that the interpreter would need in case of a deoptimization. This
449 // removes the need to bang the stack in the deoptimization blob which
450 // in turn simplifies stack overflow handling.
451 int Compile::bang_size_in_bytes() const {
452 return MAX2(_interpreter_frame_size, frame_size_in_bytes());
453 }
454
455 // ============================================================================
456 //------------------------------CompileWrapper---------------------------------
457 class CompileWrapper : public StackObj {
458 Compile *const _compile;
459 public:
460 CompileWrapper(Compile* compile);
461
462 ~CompileWrapper();
463 };
464
465 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
466 // the Compile* pointer is stored in the current ciEnv:
467 ciEnv* env = compile->env();
468 assert(env == ciEnv::current(), "must already be a ciEnv active");
469 assert(env->compiler_data() == NULL, "compile already active?");
470 env->set_compiler_data(compile);
471 assert(compile == Compile::current(), "sanity");
472
473 compile->set_type_dict(NULL);
474 compile->set_type_hwm(NULL);
475 compile->set_type_last_size(0);
476 compile->set_last_tf(NULL, NULL);
477 compile->set_indexSet_arena(NULL);
478 compile->set_indexSet_free_block_list(NULL);
479 compile->init_type_arena();
480 Type::Initialize(compile);
481 _compile->set_scratch_buffer_blob(NULL);
482 _compile->begin_method();
483 }
484 CompileWrapper::~CompileWrapper() {
485 _compile->end_method();
486 if (_compile->scratch_buffer_blob() != NULL)
487 BufferBlob::free(_compile->scratch_buffer_blob());
488 _compile->env()->set_compiler_data(NULL);
489 }
490
491
492 //----------------------------print_compile_messages---------------------------
493 void Compile::print_compile_messages() {
494 #ifndef PRODUCT
495 // Check if recompiling
496 if (_subsume_loads == false && PrintOpto) {
497 // Recompiling without allowing machine instructions to subsume loads
498 tty->print_cr("*********************************************************");
499 tty->print_cr("** Bailout: Recompile without subsuming loads **");
500 tty->print_cr("*********************************************************");
501 }
502 if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
503 // Recompiling without escape analysis
504 tty->print_cr("*********************************************************");
505 tty->print_cr("** Bailout: Recompile without escape analysis **");
506 tty->print_cr("*********************************************************");
507 }
508 if (_eliminate_boxing != EliminateAutoBox && PrintOpto) {
509 // Recompiling without boxing elimination
510 tty->print_cr("*********************************************************");
511 tty->print_cr("** Bailout: Recompile without boxing elimination **");
512 tty->print_cr("*********************************************************");
513 }
514 if (env()->break_at_compile()) {
515 // Open the debugger when compiling this method.
516 tty->print("### Breaking when compiling: ");
517 method()->print_short_name();
518 tty->cr();
519 BREAKPOINT;
520 }
521
522 if( PrintOpto ) {
523 if (is_osr_compilation()) {
524 tty->print("[OSR]%3d", _compile_id);
525 } else {
526 tty->print("%3d", _compile_id);
527 }
528 }
529 #endif
530 }
531
532
533 //-----------------------init_scratch_buffer_blob------------------------------
534 // Construct a temporary BufferBlob and cache it for this compile.
535 void Compile::init_scratch_buffer_blob(int const_size) {
536 // If there is already a scratch buffer blob allocated and the
537 // constant section is big enough, use it. Otherwise free the
538 // current and allocate a new one.
539 BufferBlob* blob = scratch_buffer_blob();
540 if ((blob != NULL) && (const_size <= _scratch_const_size)) {
541 // Use the current blob.
542 } else {
543 if (blob != NULL) {
544 BufferBlob::free(blob);
545 }
546
547 ResourceMark rm;
548 _scratch_const_size = const_size;
549 int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
550 blob = BufferBlob::create("Compile::scratch_buffer", size);
551 // Record the buffer blob for next time.
552 set_scratch_buffer_blob(blob);
553 // Have we run out of code space?
554 if (scratch_buffer_blob() == NULL) {
555 // Let CompilerBroker disable further compilations.
556 record_failure("Not enough space for scratch buffer in CodeCache");
557 return;
558 }
559 }
560
561 // Initialize the relocation buffers
562 relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
563 set_scratch_locs_memory(locs_buf);
564 }
565
566
567 //-----------------------scratch_emit_size-------------------------------------
568 // Helper function that computes size by emitting code
569 uint Compile::scratch_emit_size(const Node* n) {
570 // Start scratch_emit_size section.
571 set_in_scratch_emit_size(true);
572
573 // Emit into a trash buffer and count bytes emitted.
574 // This is a pretty expensive way to compute a size,
575 // but it works well enough if seldom used.
576 // All common fixed-size instructions are given a size
577 // method by the AD file.
578 // Note that the scratch buffer blob and locs memory are
579 // allocated at the beginning of the compile task, and
580 // may be shared by several calls to scratch_emit_size.
581 // The allocation of the scratch buffer blob is particularly
582 // expensive, since it has to grab the code cache lock.
583 BufferBlob* blob = this->scratch_buffer_blob();
584 assert(blob != NULL, "Initialize BufferBlob at start");
585 assert(blob->size() > MAX_inst_size, "sanity");
586 relocInfo* locs_buf = scratch_locs_memory();
587 address blob_begin = blob->content_begin();
588 address blob_end = (address)locs_buf;
589 assert(blob->content_contains(blob_end), "sanity");
590 CodeBuffer buf(blob_begin, blob_end - blob_begin);
591 buf.initialize_consts_size(_scratch_const_size);
592 buf.initialize_stubs_size(MAX_stubs_size);
593 assert(locs_buf != NULL, "sanity");
594 int lsize = MAX_locs_size / 3;
595 buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
596 buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
597 buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
598
599 // Do the emission.
600
601 Label fakeL; // Fake label for branch instructions.
602 Label* saveL = NULL;
603 uint save_bnum = 0;
604 bool is_branch = n->is_MachBranch();
605 if (is_branch) {
606 MacroAssembler masm(&buf);
607 masm.bind(fakeL);
608 n->as_MachBranch()->save_label(&saveL, &save_bnum);
609 n->as_MachBranch()->label_set(&fakeL, 0);
610 }
611 n->emit(buf, this->regalloc());
612
613 // Emitting into the scratch buffer should not fail
614 assert (!failing(), err_msg_res("Must not have pending failure. Reason is: %s", failure_reason()));
615
616 if (is_branch) // Restore label.
617 n->as_MachBranch()->label_set(saveL, save_bnum);
618
619 // End scratch_emit_size section.
620 set_in_scratch_emit_size(false);
621
622 return buf.insts_size();
623 }
624
625
626 // ============================================================================
627 //------------------------------Compile standard-------------------------------
628 debug_only( int Compile::_debug_idx = 100000; )
629
630 // Compile a method. entry_bci is -1 for normal compilations and indicates
631 // the continuation bci for on stack replacement.
632
633
634 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci,
635 bool subsume_loads, bool do_escape_analysis, bool eliminate_boxing )
636 : Phase(Compiler),
637 _env(ci_env),
638 _log(ci_env->log()),
639 _compile_id(ci_env->compile_id()),
640 _save_argument_registers(false),
641 _stub_name(NULL),
642 _stub_function(NULL),
643 _stub_entry_point(NULL),
644 _method(target),
645 _entry_bci(osr_bci),
646 _initial_gvn(NULL),
647 _for_igvn(NULL),
648 _warm_calls(NULL),
649 _subsume_loads(subsume_loads),
650 _do_escape_analysis(do_escape_analysis),
651 _eliminate_boxing(eliminate_boxing),
652 _failure_reason(NULL),
653 _code_buffer("Compile::Fill_buffer"),
654 _orig_pc_slot(0),
655 _orig_pc_slot_offset_in_bytes(0),
656 _has_method_handle_invokes(false),
657 _mach_constant_base_node(NULL),
658 _node_bundling_limit(0),
659 _node_bundling_base(NULL),
660 _java_calls(0),
661 _inner_loops(0),
662 _scratch_const_size(-1),
663 _in_scratch_emit_size(false),
664 _dead_node_list(comp_arena()),
665 _dead_node_count(0),
666 #ifndef PRODUCT
667 _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
668 _in_dump_cnt(0),
669 _printer(IdealGraphPrinter::printer()),
670 #endif
671 _congraph(NULL),
672 _comp_arena(mtCompiler),
673 _node_arena(mtCompiler),
674 _old_arena(mtCompiler),
675 _Compile_types(mtCompiler),
676 _replay_inline_data(NULL),
677 _late_inlines(comp_arena(), 2, 0, NULL),
678 _string_late_inlines(comp_arena(), 2, 0, NULL),
679 _boxing_late_inlines(comp_arena(), 2, 0, NULL),
680 _late_inlines_pos(0),
681 _number_of_mh_late_inlines(0),
682 _inlining_progress(false),
683 _inlining_incrementally(false),
684 _print_inlining_list(NULL),
685 _print_inlining_idx(0),
686 _interpreter_frame_size(0),
687 _max_node_limit(MaxNodeLimit) {
688 C = this;
689
690 CompileWrapper cw(this);
691 #ifndef PRODUCT
692 if (TimeCompiler2) {
693 tty->print(" ");
694 target->holder()->name()->print();
695 tty->print(".");
696 target->print_short_name();
697 tty->print(" ");
698 }
699 TraceTime t1("Total compilation time", &_t_totalCompilation, TimeCompiler, TimeCompiler2);
700 TraceTime t2(NULL, &_t_methodCompilation, TimeCompiler, false);
701 bool print_opto_assembly = PrintOptoAssembly || _method->has_option("PrintOptoAssembly");
702 if (!print_opto_assembly) {
703 bool print_assembly = (PrintAssembly || _method->should_print_assembly());
704 if (print_assembly && !Disassembler::can_decode()) {
705 tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
706 print_opto_assembly = true;
707 }
708 }
709 set_print_assembly(print_opto_assembly);
710 set_parsed_irreducible_loop(false);
711
712 if (method()->has_option("ReplayInline")) {
713 _replay_inline_data = ciReplay::load_inline_data(method(), entry_bci(), ci_env->comp_level());
714 }
715 #endif
716 set_print_inlining(PrintInlining || method()->has_option("PrintInlining") NOT_PRODUCT( || PrintOptoInlining));
717 set_print_intrinsics(PrintIntrinsics || method()->has_option("PrintIntrinsics"));
718 set_has_irreducible_loop(true); // conservative until build_loop_tree() reset it
719
720 if (ProfileTraps RTM_OPT_ONLY( || UseRTMLocking )) {
721 // Make sure the method being compiled gets its own MDO,
722 // so we can at least track the decompile_count().
723 // Need MDO to record RTM code generation state.
724 method()->ensure_method_data();
725 }
726
727 Init(::AliasLevel);
728
729
730 print_compile_messages();
731
732 _ilt = InlineTree::build_inline_tree_root();
733
734 // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
735 assert(num_alias_types() >= AliasIdxRaw, "");
736
737 #define MINIMUM_NODE_HASH 1023
738 // Node list that Iterative GVN will start with
739 Unique_Node_List for_igvn(comp_arena());
740 set_for_igvn(&for_igvn);
741
742 // GVN that will be run immediately on new nodes
743 uint estimated_size = method()->code_size()*4+64;
744 estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
745 PhaseGVN gvn(node_arena(), estimated_size);
746 set_initial_gvn(&gvn);
747
748 if (print_inlining() || print_intrinsics()) {
749 _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
750 }
751 { // Scope for timing the parser
752 TracePhase t3("parse", &_t_parser, true);
753
754 // Put top into the hash table ASAP.
755 initial_gvn()->transform_no_reclaim(top());
756
757 // Set up tf(), start(), and find a CallGenerator.
758 CallGenerator* cg = NULL;
759 if (is_osr_compilation()) {
760 const TypeTuple *domain = StartOSRNode::osr_domain();
761 const TypeTuple *range = TypeTuple::make_range(method()->signature());
762 init_tf(TypeFunc::make(domain, range));
763 StartNode* s = new (this) StartOSRNode(root(), domain);
764 initial_gvn()->set_type_bottom(s);
765 init_start(s);
766 cg = CallGenerator::for_osr(method(), entry_bci());
767 } else {
768 // Normal case.
769 init_tf(TypeFunc::make(method()));
770 StartNode* s = new (this) StartNode(root(), tf()->domain());
771 initial_gvn()->set_type_bottom(s);
772 init_start(s);
773 if (method()->intrinsic_id() == vmIntrinsics::_Reference_get && UseG1GC) {
774 // With java.lang.ref.reference.get() we must go through the
775 // intrinsic when G1 is enabled - even when get() is the root
776 // method of the compile - so that, if necessary, the value in
777 // the referent field of the reference object gets recorded by
778 // the pre-barrier code.
779 // Specifically, if G1 is enabled, the value in the referent
780 // field is recorded by the G1 SATB pre barrier. This will
781 // result in the referent being marked live and the reference
782 // object removed from the list of discovered references during
783 // reference processing.
784 cg = find_intrinsic(method(), false);
785 }
786 if (cg == NULL) {
787 float past_uses = method()->interpreter_invocation_count();
788 float expected_uses = past_uses;
789 cg = CallGenerator::for_inline(method(), expected_uses);
790 }
791 }
792 if (failing()) return;
793 if (cg == NULL) {
794 record_method_not_compilable_all_tiers("cannot parse method");
795 return;
796 }
797 JVMState* jvms = build_start_state(start(), tf());
798 if ((jvms = cg->generate(jvms)) == NULL) {
799 if (!failure_reason_is(C2Compiler::retry_class_loading_during_parsing())) {
800 record_method_not_compilable("method parse failed");
801 }
802 return;
803 }
804 GraphKit kit(jvms);
805
806 if (!kit.stopped()) {
807 // Accept return values, and transfer control we know not where.
808 // This is done by a special, unique ReturnNode bound to root.
809 return_values(kit.jvms());
810 }
811
812 if (kit.has_exceptions()) {
813 // Any exceptions that escape from this call must be rethrown
814 // to whatever caller is dynamically above us on the stack.
815 // This is done by a special, unique RethrowNode bound to root.
816 rethrow_exceptions(kit.transfer_exceptions_into_jvms());
817 }
818
819 assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
820
821 if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
822 inline_string_calls(true);
823 }
824
825 if (failing()) return;
826
827 print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
828
829 // Remove clutter produced by parsing.
830 if (!failing()) {
831 ResourceMark rm;
832 PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
833 }
834 }
835
836 // Note: Large methods are capped off in do_one_bytecode().
837 if (failing()) return;
838
839 // After parsing, node notes are no longer automagic.
840 // They must be propagated by register_new_node_with_optimizer(),
841 // clone(), or the like.
842 set_default_node_notes(NULL);
843
844 for (;;) {
845 int successes = Inline_Warm();
846 if (failing()) return;
847 if (successes == 0) break;
848 }
849
850 // Drain the list.
851 Finish_Warm();
852 #ifndef PRODUCT
853 if (_printer) {
854 _printer->print_inlining(this);
855 }
856 #endif
857
858 if (failing()) return;
859 NOT_PRODUCT( verify_graph_edges(); )
860
861 // Now optimize
862 Optimize();
863 if (failing()) return;
864 NOT_PRODUCT( verify_graph_edges(); )
865
866 #ifndef PRODUCT
867 if (PrintIdeal) {
868 ttyLocker ttyl; // keep the following output all in one block
869 // This output goes directly to the tty, not the compiler log.
870 // To enable tools to match it up with the compilation activity,
871 // be sure to tag this tty output with the compile ID.
872 if (xtty != NULL) {
873 xtty->head("ideal compile_id='%d'%s", compile_id(),
874 is_osr_compilation() ? " compile_kind='osr'" :
875 "");
876 }
877 root()->dump(9999);
878 if (xtty != NULL) {
879 xtty->tail("ideal");
880 }
881 }
882 #endif
883
884 NOT_PRODUCT( verify_barriers(); )
885
886 // Dump compilation data to replay it.
887 if (method()->has_option("DumpReplay")) {
888 env()->dump_replay_data(_compile_id);
889 }
890 if (method()->has_option("DumpInline") && (ilt() != NULL)) {
891 env()->dump_inline_data(_compile_id);
892 }
893
894 // Now that we know the size of all the monitors we can add a fixed slot
895 // for the original deopt pc.
896
897 _orig_pc_slot = fixed_slots();
898 int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
899 set_fixed_slots(next_slot);
900
901 // Compute when to use implicit null checks. Used by matching trap based
902 // nodes and NullCheck optimization.
903 set_allowed_deopt_reasons();
904
905 // Now generate code
906 Code_Gen();
907 if (failing()) return;
908
909 // Check if we want to skip execution of all compiled code.
910 {
911 #ifndef PRODUCT
912 if (OptoNoExecute) {
913 record_method_not_compilable("+OptoNoExecute"); // Flag as failed
914 return;
915 }
916 TracePhase t2("install_code", &_t_registerMethod, TimeCompiler);
917 #endif
918
919 if (is_osr_compilation()) {
920 _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
921 _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
922 } else {
923 _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
924 _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
925 }
926
927 env()->register_method(_method, _entry_bci,
928 &_code_offsets,
929 _orig_pc_slot_offset_in_bytes,
930 code_buffer(),
931 frame_size_in_words(), _oop_map_set,
932 &_handler_table, &_inc_table,
933 compiler,
934 env()->comp_level(),
935 has_unsafe_access(),
936 SharedRuntime::is_wide_vector(max_vector_size()),
937 rtm_state()
938 );
939
940 if (log() != NULL) // Print code cache state into compiler log
941 log()->code_cache_state();
942 }
943 }
944
945 //------------------------------Compile----------------------------------------
946 // Compile a runtime stub
947 Compile::Compile( ciEnv* ci_env,
948 TypeFunc_generator generator,
949 address stub_function,
950 const char *stub_name,
951 int is_fancy_jump,
952 bool pass_tls,
953 bool save_arg_registers,
954 bool return_pc )
955 : Phase(Compiler),
956 _env(ci_env),
957 _log(ci_env->log()),
958 _compile_id(0),
959 _save_argument_registers(save_arg_registers),
960 _method(NULL),
961 _stub_name(stub_name),
962 _stub_function(stub_function),
963 _stub_entry_point(NULL),
964 _entry_bci(InvocationEntryBci),
965 _initial_gvn(NULL),
966 _for_igvn(NULL),
967 _warm_calls(NULL),
968 _orig_pc_slot(0),
969 _orig_pc_slot_offset_in_bytes(0),
970 _subsume_loads(true),
971 _do_escape_analysis(false),
972 _eliminate_boxing(false),
973 _failure_reason(NULL),
974 _code_buffer("Compile::Fill_buffer"),
975 _has_method_handle_invokes(false),
976 _mach_constant_base_node(NULL),
977 _node_bundling_limit(0),
978 _node_bundling_base(NULL),
979 _java_calls(0),
980 _inner_loops(0),
981 #ifndef PRODUCT
982 _trace_opto_output(TraceOptoOutput),
983 _in_dump_cnt(0),
984 _printer(NULL),
985 #endif
986 _comp_arena(mtCompiler),
987 _node_arena(mtCompiler),
988 _old_arena(mtCompiler),
989 _Compile_types(mtCompiler),
990 _dead_node_list(comp_arena()),
991 _dead_node_count(0),
992 _congraph(NULL),
993 _replay_inline_data(NULL),
994 _number_of_mh_late_inlines(0),
995 _inlining_progress(false),
996 _inlining_incrementally(false),
997 _print_inlining_list(NULL),
998 _print_inlining_idx(0),
999 _allowed_reasons(0),
1000 _interpreter_frame_size(0),
1001 _max_node_limit(MaxNodeLimit) {
1002 C = this;
1003
1004 #ifndef PRODUCT
1005 TraceTime t1(NULL, &_t_totalCompilation, TimeCompiler, false);
1006 TraceTime t2(NULL, &_t_stubCompilation, TimeCompiler, false);
1007 set_print_assembly(PrintFrameConverterAssembly);
1008 set_parsed_irreducible_loop(false);
1009 #endif
1010 set_has_irreducible_loop(false); // no loops
1011
1012 CompileWrapper cw(this);
1013 Init(/*AliasLevel=*/ 0);
1014 init_tf((*generator)());
1015
1016 {
1017 // The following is a dummy for the sake of GraphKit::gen_stub
1018 Unique_Node_List for_igvn(comp_arena());
1019 set_for_igvn(&for_igvn); // not used, but some GraphKit guys push on this
1020 PhaseGVN gvn(Thread::current()->resource_area(),255);
1021 set_initial_gvn(&gvn); // not significant, but GraphKit guys use it pervasively
1022 gvn.transform_no_reclaim(top());
1023
1024 GraphKit kit;
1025 kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
1026 }
1027
1028 NOT_PRODUCT( verify_graph_edges(); )
1029 Code_Gen();
1030 if (failing()) return;
1031
1032
1033 // Entry point will be accessed using compile->stub_entry_point();
1034 if (code_buffer() == NULL) {
1035 Matcher::soft_match_failure();
1036 } else {
1037 if (PrintAssembly && (WizardMode || Verbose))
1038 tty->print_cr("### Stub::%s", stub_name);
1039
1040 if (!failing()) {
1041 assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
1042
1043 // Make the NMethod
1044 // For now we mark the frame as never safe for profile stackwalking
1045 RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
1046 code_buffer(),
1047 CodeOffsets::frame_never_safe,
1048 // _code_offsets.value(CodeOffsets::Frame_Complete),
1049 frame_size_in_words(),
1050 _oop_map_set,
1051 save_arg_registers);
1052 assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
1053
1054 _stub_entry_point = rs->entry_point();
1055 }
1056 }
1057 }
1058
1059 //------------------------------Init-------------------------------------------
1060 // Prepare for a single compilation
1061 void Compile::Init(int aliaslevel) {
1062 _unique = 0;
1063 _regalloc = NULL;
1064
1065 _tf = NULL; // filled in later
1066 _top = NULL; // cached later
1067 _matcher = NULL; // filled in later
1068 _cfg = NULL; // filled in later
1069
1070 set_24_bit_selection_and_mode(Use24BitFP, false);
1071
1072 _node_note_array = NULL;
1073 _default_node_notes = NULL;
1074
1075 _immutable_memory = NULL; // filled in at first inquiry
1076
1077 // Globally visible Nodes
1078 // First set TOP to NULL to give safe behavior during creation of RootNode
1079 set_cached_top_node(NULL);
1080 set_root(new (this) RootNode());
1081 // Now that you have a Root to point to, create the real TOP
1082 set_cached_top_node( new (this) ConNode(Type::TOP) );
1083 set_recent_alloc(NULL, NULL);
1084
1085 // Create Debug Information Recorder to record scopes, oopmaps, etc.
1086 env()->set_oop_recorder(new OopRecorder(env()->arena()));
1087 env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
1088 env()->set_dependencies(new Dependencies(env()));
1089
1090 _fixed_slots = 0;
1091 set_has_split_ifs(false);
1092 set_has_loops(has_method() && method()->has_loops()); // first approximation
1093 set_has_stringbuilder(false);
1094 set_has_boxed_value(false);
1095 _trap_can_recompile = false; // no traps emitted yet
1096 _major_progress = true; // start out assuming good things will happen
1097 set_has_unsafe_access(false);
1098 set_max_vector_size(0);
1099 Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
1100 set_decompile_count(0);
1101
1102 set_do_freq_based_layout(BlockLayoutByFrequency || method_has_option("BlockLayoutByFrequency"));
1103 set_num_loop_opts(LoopOptsCount);
1104 set_do_inlining(Inline);
1105 set_max_inline_size(MaxInlineSize);
1106 set_freq_inline_size(FreqInlineSize);
1107 set_do_scheduling(OptoScheduling);
1108 set_do_count_invocations(false);
1109 set_do_method_data_update(false);
1110 set_rtm_state(NoRTM); // No RTM lock eliding by default
1111 method_has_option_value("MaxNodeLimit", _max_node_limit);
1112 #if INCLUDE_RTM_OPT
1113 if (UseRTMLocking && has_method() && (method()->method_data_or_null() != NULL)) {
1114 int rtm_state = method()->method_data()->rtm_state();
1115 if (method_has_option("NoRTMLockEliding") || ((rtm_state & NoRTM) != 0)) {
1116 // Don't generate RTM lock eliding code.
1117 set_rtm_state(NoRTM);
1118 } else if (method_has_option("UseRTMLockEliding") || ((rtm_state & UseRTM) != 0) || !UseRTMDeopt) {
1119 // Generate RTM lock eliding code without abort ratio calculation code.
1120 set_rtm_state(UseRTM);
1121 } else if (UseRTMDeopt) {
1122 // Generate RTM lock eliding code and include abort ratio calculation
1123 // code if UseRTMDeopt is on.
1124 set_rtm_state(ProfileRTM);
1125 }
1126 }
1127 #endif
1128 if (debug_info()->recording_non_safepoints()) {
1129 set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
1130 (comp_arena(), 8, 0, NULL));
1131 set_default_node_notes(Node_Notes::make(this));
1132 }
1133
1134 // // -- Initialize types before each compile --
1135 // // Update cached type information
1136 // if( _method && _method->constants() )
1137 // Type::update_loaded_types(_method, _method->constants());
1138
1139 // Init alias_type map.
1140 if (!_do_escape_analysis && aliaslevel == 3)
1141 aliaslevel = 2; // No unique types without escape analysis
1142 _AliasLevel = aliaslevel;
1143 const int grow_ats = 16;
1144 _max_alias_types = grow_ats;
1145 _alias_types = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
1146 AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType, grow_ats);
1147 Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
1148 {
1149 for (int i = 0; i < grow_ats; i++) _alias_types[i] = &ats[i];
1150 }
1151 // Initialize the first few types.
1152 _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
1153 _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1154 _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1155 _num_alias_types = AliasIdxRaw+1;
1156 // Zero out the alias type cache.
1157 Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1158 // A NULL adr_type hits in the cache right away. Preload the right answer.
1159 probe_alias_cache(NULL)->_index = AliasIdxTop;
1160
1161 _intrinsics = NULL;
1162 _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1163 _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1164 _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1165 _range_check_casts = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1166 register_library_intrinsics();
1167 #ifdef ASSERT
1168 _type_verify_symmetry = true;
1169 #endif
1170 }
1171
1172 //---------------------------init_start----------------------------------------
1173 // Install the StartNode on this compile object.
1174 void Compile::init_start(StartNode* s) {
1175 if (failing())
1176 return; // already failing
1177 assert(s == start(), "");
1178 }
1179
1180 StartNode* Compile::start() const {
1181 assert(!failing(), "");
1182 for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1183 Node* start = root()->fast_out(i);
1184 if( start->is_Start() )
1185 return start->as_Start();
1186 }
1187 fatal("Did not find Start node!");
1188 return NULL;
1189 }
1190
1191 //-------------------------------immutable_memory-------------------------------------
1192 // Access immutable memory
1193 Node* Compile::immutable_memory() {
1194 if (_immutable_memory != NULL) {
1195 return _immutable_memory;
1196 }
1197 StartNode* s = start();
1198 for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1199 Node *p = s->fast_out(i);
1200 if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1201 _immutable_memory = p;
1202 return _immutable_memory;
1203 }
1204 }
1205 ShouldNotReachHere();
1206 return NULL;
1207 }
1208
1209 //----------------------set_cached_top_node------------------------------------
1210 // Install the cached top node, and make sure Node::is_top works correctly.
1211 void Compile::set_cached_top_node(Node* tn) {
1212 if (tn != NULL) verify_top(tn);
1213 Node* old_top = _top;
1214 _top = tn;
1215 // Calling Node::setup_is_top allows the nodes the chance to adjust
1216 // their _out arrays.
1217 if (_top != NULL) _top->setup_is_top();
1218 if (old_top != NULL) old_top->setup_is_top();
1219 assert(_top == NULL || top()->is_top(), "");
1220 }
1221
1222 #ifdef ASSERT
1223 uint Compile::count_live_nodes_by_graph_walk() {
1224 Unique_Node_List useful(comp_arena());
1225 // Get useful node list by walking the graph.
1226 identify_useful_nodes(useful);
1227 return useful.size();
1228 }
1229
1230 void Compile::print_missing_nodes() {
1231
1232 // Return if CompileLog is NULL and PrintIdealNodeCount is false.
1233 if ((_log == NULL) && (! PrintIdealNodeCount)) {
1234 return;
1235 }
1236
1237 // This is an expensive function. It is executed only when the user
1238 // specifies VerifyIdealNodeCount option or otherwise knows the
1239 // additional work that needs to be done to identify reachable nodes
1240 // by walking the flow graph and find the missing ones using
1241 // _dead_node_list.
1242
1243 Unique_Node_List useful(comp_arena());
1244 // Get useful node list by walking the graph.
1245 identify_useful_nodes(useful);
1246
1247 uint l_nodes = C->live_nodes();
1248 uint l_nodes_by_walk = useful.size();
1249
1250 if (l_nodes != l_nodes_by_walk) {
1251 if (_log != NULL) {
1252 _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
1253 _log->stamp();
1254 _log->end_head();
1255 }
1256 VectorSet& useful_member_set = useful.member_set();
1257 int last_idx = l_nodes_by_walk;
1258 for (int i = 0; i < last_idx; i++) {
1259 if (useful_member_set.test(i)) {
1260 if (_dead_node_list.test(i)) {
1261 if (_log != NULL) {
1262 _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
1263 }
1264 if (PrintIdealNodeCount) {
1265 // Print the log message to tty
1266 tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
1267 useful.at(i)->dump();
1268 }
1269 }
1270 }
1271 else if (! _dead_node_list.test(i)) {
1272 if (_log != NULL) {
1273 _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
1274 }
1275 if (PrintIdealNodeCount) {
1276 // Print the log message to tty
1277 tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
1278 }
1279 }
1280 }
1281 if (_log != NULL) {
1282 _log->tail("mismatched_nodes");
1283 }
1284 }
1285 }
1286 #endif
1287
1288 #ifndef PRODUCT
1289 void Compile::verify_top(Node* tn) const {
1290 if (tn != NULL) {
1291 assert(tn->is_Con(), "top node must be a constant");
1292 assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1293 assert(tn->in(0) != NULL, "must have live top node");
1294 }
1295 }
1296 #endif
1297
1298
1299 ///-------------------Managing Per-Node Debug & Profile Info-------------------
1300
1301 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1302 guarantee(arr != NULL, "");
1303 int num_blocks = arr->length();
1304 if (grow_by < num_blocks) grow_by = num_blocks;
1305 int num_notes = grow_by * _node_notes_block_size;
1306 Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1307 Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1308 while (num_notes > 0) {
1309 arr->append(notes);
1310 notes += _node_notes_block_size;
1311 num_notes -= _node_notes_block_size;
1312 }
1313 assert(num_notes == 0, "exact multiple, please");
1314 }
1315
1316 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1317 if (source == NULL || dest == NULL) return false;
1318
1319 if (dest->is_Con())
1320 return false; // Do not push debug info onto constants.
1321
1322 #ifdef ASSERT
1323 // Leave a bread crumb trail pointing to the original node:
1324 if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
1325 dest->set_debug_orig(source);
1326 }
1327 #endif
1328
1329 if (node_note_array() == NULL)
1330 return false; // Not collecting any notes now.
1331
1332 // This is a copy onto a pre-existing node, which may already have notes.
1333 // If both nodes have notes, do not overwrite any pre-existing notes.
1334 Node_Notes* source_notes = node_notes_at(source->_idx);
1335 if (source_notes == NULL || source_notes->is_clear()) return false;
1336 Node_Notes* dest_notes = node_notes_at(dest->_idx);
1337 if (dest_notes == NULL || dest_notes->is_clear()) {
1338 return set_node_notes_at(dest->_idx, source_notes);
1339 }
1340
1341 Node_Notes merged_notes = (*source_notes);
1342 // The order of operations here ensures that dest notes will win...
1343 merged_notes.update_from(dest_notes);
1344 return set_node_notes_at(dest->_idx, &merged_notes);
1345 }
1346
1347
1348 //--------------------------allow_range_check_smearing-------------------------
1349 // Gating condition for coalescing similar range checks.
1350 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1351 // single covering check that is at least as strong as any of them.
1352 // If the optimization succeeds, the simplified (strengthened) range check
1353 // will always succeed. If it fails, we will deopt, and then give up
1354 // on the optimization.
1355 bool Compile::allow_range_check_smearing() const {
1356 // If this method has already thrown a range-check,
1357 // assume it was because we already tried range smearing
1358 // and it failed.
1359 uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1360 return !already_trapped;
1361 }
1362
1363
1364 //------------------------------flatten_alias_type-----------------------------
1365 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1366 int offset = tj->offset();
1367 TypePtr::PTR ptr = tj->ptr();
1368
1369 // Known instance (scalarizable allocation) alias only with itself.
1370 bool is_known_inst = tj->isa_oopptr() != NULL &&
1371 tj->is_oopptr()->is_known_instance();
1372
1373 // Process weird unsafe references.
1374 if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1375 assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
1376 assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1377 tj = TypeOopPtr::BOTTOM;
1378 ptr = tj->ptr();
1379 offset = tj->offset();
1380 }
1381
1382 // Array pointers need some flattening
1383 const TypeAryPtr *ta = tj->isa_aryptr();
1384 if (ta && ta->is_stable()) {
1385 // Erase stability property for alias analysis.
1386 tj = ta = ta->cast_to_stable(false);
1387 }
1388 if( ta && is_known_inst ) {
1389 if ( offset != Type::OffsetBot &&
1390 offset > arrayOopDesc::length_offset_in_bytes() ) {
1391 offset = Type::OffsetBot; // Flatten constant access into array body only
1392 tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
1393 }
1394 } else if( ta && _AliasLevel >= 2 ) {
1395 // For arrays indexed by constant indices, we flatten the alias
1396 // space to include all of the array body. Only the header, klass
1397 // and array length can be accessed un-aliased.
1398 if( offset != Type::OffsetBot ) {
1399 if( ta->const_oop() ) { // MethodData* or Method*
1400 offset = Type::OffsetBot; // Flatten constant access into array body
1401 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
1402 } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1403 // range is OK as-is.
1404 tj = ta = TypeAryPtr::RANGE;
1405 } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1406 tj = TypeInstPtr::KLASS; // all klass loads look alike
1407 ta = TypeAryPtr::RANGE; // generic ignored junk
1408 ptr = TypePtr::BotPTR;
1409 } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1410 tj = TypeInstPtr::MARK;
1411 ta = TypeAryPtr::RANGE; // generic ignored junk
1412 ptr = TypePtr::BotPTR;
1413 } else { // Random constant offset into array body
1414 offset = Type::OffsetBot; // Flatten constant access into array body
1415 tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
1416 }
1417 }
1418 // Arrays of fixed size alias with arrays of unknown size.
1419 if (ta->size() != TypeInt::POS) {
1420 const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1421 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
1422 }
1423 // Arrays of known objects become arrays of unknown objects.
1424 if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1425 const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1426 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1427 }
1428 if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1429 const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1430 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1431 }
1432 // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1433 // cannot be distinguished by bytecode alone.
1434 if (ta->elem() == TypeInt::BOOL) {
1435 const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1436 ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1437 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
1438 }
1439 // During the 2nd round of IterGVN, NotNull castings are removed.
1440 // Make sure the Bottom and NotNull variants alias the same.
1441 // Also, make sure exact and non-exact variants alias the same.
1442 if (ptr == TypePtr::NotNull || ta->klass_is_exact() || ta->speculative() != NULL) {
1443 tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
1444 }
1445 }
1446
1447 // Oop pointers need some flattening
1448 const TypeInstPtr *to = tj->isa_instptr();
1449 if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
1450 ciInstanceKlass *k = to->klass()->as_instance_klass();
1451 if( ptr == TypePtr::Constant ) {
1452 if (to->klass() != ciEnv::current()->Class_klass() ||
1453 offset < k->size_helper() * wordSize) {
1454 // No constant oop pointers (such as Strings); they alias with
1455 // unknown strings.
1456 assert(!is_known_inst, "not scalarizable allocation");
1457 tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1458 }
1459 } else if( is_known_inst ) {
1460 tj = to; // Keep NotNull and klass_is_exact for instance type
1461 } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1462 // During the 2nd round of IterGVN, NotNull castings are removed.
1463 // Make sure the Bottom and NotNull variants alias the same.
1464 // Also, make sure exact and non-exact variants alias the same.
1465 tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1466 }
1467 if (to->speculative() != NULL) {
1468 tj = to = TypeInstPtr::make(to->ptr(),to->klass(),to->klass_is_exact(),to->const_oop(),to->offset(), to->instance_id());
1469 }
1470 // Canonicalize the holder of this field
1471 if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1472 // First handle header references such as a LoadKlassNode, even if the
1473 // object's klass is unloaded at compile time (4965979).
1474 if (!is_known_inst) { // Do it only for non-instance types
1475 tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
1476 }
1477 } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
1478 // Static fields are in the space above the normal instance
1479 // fields in the java.lang.Class instance.
1480 if (to->klass() != ciEnv::current()->Class_klass()) {
1481 to = NULL;
1482 tj = TypeOopPtr::BOTTOM;
1483 offset = tj->offset();
1484 }
1485 } else {
1486 ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
1487 if (!k->equals(canonical_holder) || tj->offset() != offset) {
1488 if( is_known_inst ) {
1489 tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
1490 } else {
1491 tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
1492 }
1493 }
1494 }
1495 }
1496
1497 // Klass pointers to object array klasses need some flattening
1498 const TypeKlassPtr *tk = tj->isa_klassptr();
1499 if( tk ) {
1500 // If we are referencing a field within a Klass, we need
1501 // to assume the worst case of an Object. Both exact and
1502 // inexact types must flatten to the same alias class so
1503 // use NotNull as the PTR.
1504 if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1505
1506 tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
1507 TypeKlassPtr::OBJECT->klass(),
1508 offset);
1509 }
1510
1511 ciKlass* klass = tk->klass();
1512 if( klass->is_obj_array_klass() ) {
1513 ciKlass* k = TypeAryPtr::OOPS->klass();
1514 if( !k || !k->is_loaded() ) // Only fails for some -Xcomp runs
1515 k = TypeInstPtr::BOTTOM->klass();
1516 tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
1517 }
1518
1519 // Check for precise loads from the primary supertype array and force them
1520 // to the supertype cache alias index. Check for generic array loads from
1521 // the primary supertype array and also force them to the supertype cache
1522 // alias index. Since the same load can reach both, we need to merge
1523 // these 2 disparate memories into the same alias class. Since the
1524 // primary supertype array is read-only, there's no chance of confusion
1525 // where we bypass an array load and an array store.
1526 int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
1527 if (offset == Type::OffsetBot ||
1528 (offset >= primary_supers_offset &&
1529 offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
1530 offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
1531 offset = in_bytes(Klass::secondary_super_cache_offset());
1532 tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
1533 }
1534 }
1535
1536 // Flatten all Raw pointers together.
1537 if (tj->base() == Type::RawPtr)
1538 tj = TypeRawPtr::BOTTOM;
1539
1540 if (tj->base() == Type::AnyPtr)
1541 tj = TypePtr::BOTTOM; // An error, which the caller must check for.
1542
1543 // Flatten all to bottom for now
1544 switch( _AliasLevel ) {
1545 case 0:
1546 tj = TypePtr::BOTTOM;
1547 break;
1548 case 1: // Flatten to: oop, static, field or array
1549 switch (tj->base()) {
1550 //case Type::AryPtr: tj = TypeAryPtr::RANGE; break;
1551 case Type::RawPtr: tj = TypeRawPtr::BOTTOM; break;
1552 case Type::AryPtr: // do not distinguish arrays at all
1553 case Type::InstPtr: tj = TypeInstPtr::BOTTOM; break;
1554 case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
1555 case Type::AnyPtr: tj = TypePtr::BOTTOM; break; // caller checks it
1556 default: ShouldNotReachHere();
1557 }
1558 break;
1559 case 2: // No collapsing at level 2; keep all splits
1560 case 3: // No collapsing at level 3; keep all splits
1561 break;
1562 default:
1563 Unimplemented();
1564 }
1565
1566 offset = tj->offset();
1567 assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1568
1569 assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1570 (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1571 (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1572 (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1573 (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1574 (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1575 (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr) ,
1576 "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1577 assert( tj->ptr() != TypePtr::TopPTR &&
1578 tj->ptr() != TypePtr::AnyNull &&
1579 tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1580 // assert( tj->ptr() != TypePtr::Constant ||
1581 // tj->base() == Type::RawPtr ||
1582 // tj->base() == Type::KlassPtr, "No constant oop addresses" );
1583
1584 return tj;
1585 }
1586
1587 void Compile::AliasType::Init(int i, const TypePtr* at) {
1588 _index = i;
1589 _adr_type = at;
1590 _field = NULL;
1591 _element = NULL;
1592 _is_rewritable = true; // default
1593 const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
1594 if (atoop != NULL && atoop->is_known_instance()) {
1595 const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1596 _general_index = Compile::current()->get_alias_index(gt);
1597 } else {
1598 _general_index = 0;
1599 }
1600 }
1601
1602 BasicType Compile::AliasType::basic_type() const {
1603 if (element() != NULL) {
1604 const Type* element = adr_type()->is_aryptr()->elem();
1605 return element->isa_narrowoop() ? T_OBJECT : element->array_element_basic_type();
1606 } if (field() != NULL) {
1607 return field()->layout_type();
1608 } else {
1609 return T_ILLEGAL; // unknown
1610 }
1611 }
1612
1613 //---------------------------------print_on------------------------------------
1614 #ifndef PRODUCT
1615 void Compile::AliasType::print_on(outputStream* st) {
1616 if (index() < 10)
1617 st->print("@ <%d> ", index());
1618 else st->print("@ <%d>", index());
1619 st->print(is_rewritable() ? " " : " RO");
1620 int offset = adr_type()->offset();
1621 if (offset == Type::OffsetBot)
1622 st->print(" +any");
1623 else st->print(" +%-3d", offset);
1624 st->print(" in ");
1625 adr_type()->dump_on(st);
1626 const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1627 if (field() != NULL && tjp) {
1628 if (tjp->klass() != field()->holder() ||
1629 tjp->offset() != field()->offset_in_bytes()) {
1630 st->print(" != ");
1631 field()->print();
1632 st->print(" ***");
1633 }
1634 }
1635 }
1636
1637 void print_alias_types() {
1638 Compile* C = Compile::current();
1639 tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1640 for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1641 C->alias_type(idx)->print_on(tty);
1642 tty->cr();
1643 }
1644 }
1645 #endif
1646
1647
1648 //----------------------------probe_alias_cache--------------------------------
1649 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1650 intptr_t key = (intptr_t) adr_type;
1651 key ^= key >> logAliasCacheSize;
1652 return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1653 }
1654
1655
1656 //-----------------------------grow_alias_types--------------------------------
1657 void Compile::grow_alias_types() {
1658 const int old_ats = _max_alias_types; // how many before?
1659 const int new_ats = old_ats; // how many more?
1660 const int grow_ats = old_ats+new_ats; // how many now?
1661 _max_alias_types = grow_ats;
1662 _alias_types = REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1663 AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1664 Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1665 for (int i = 0; i < new_ats; i++) _alias_types[old_ats+i] = &ats[i];
1666 }
1667
1668
1669 //--------------------------------find_alias_type------------------------------
1670 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1671 if (_AliasLevel == 0)
1672 return alias_type(AliasIdxBot);
1673
1674 AliasCacheEntry* ace = probe_alias_cache(adr_type);
1675 if (ace->_adr_type == adr_type) {
1676 return alias_type(ace->_index);
1677 }
1678
1679 // Handle special cases.
1680 if (adr_type == NULL) return alias_type(AliasIdxTop);
1681 if (adr_type == TypePtr::BOTTOM) return alias_type(AliasIdxBot);
1682
1683 // Do it the slow way.
1684 const TypePtr* flat = flatten_alias_type(adr_type);
1685
1686 #ifdef ASSERT
1687 {
1688 ResourceMark rm;
1689 assert(flat == flatten_alias_type(flat),
1690 err_msg("not idempotent: adr_type = %s; flat = %s => %s", Type::str(adr_type),
1691 Type::str(flat), Type::str(flatten_alias_type(flat))));
1692 assert(flat != TypePtr::BOTTOM,
1693 err_msg("cannot alias-analyze an untyped ptr: adr_type = %s", Type::str(adr_type)));
1694 if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1695 const TypeOopPtr* foop = flat->is_oopptr();
1696 // Scalarizable allocations have exact klass always.
1697 bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1698 const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1699 assert(foop == flatten_alias_type(xoop),
1700 err_msg("exactness must not affect alias type: foop = %s; xoop = %s",
1701 Type::str(foop), Type::str(xoop)));
1702 }
1703 }
1704 #endif
1705
1706 int idx = AliasIdxTop;
1707 for (int i = 0; i < num_alias_types(); i++) {
1708 if (alias_type(i)->adr_type() == flat) {
1709 idx = i;
1710 break;
1711 }
1712 }
1713
1714 if (idx == AliasIdxTop) {
1715 if (no_create) return NULL;
1716 // Grow the array if necessary.
1717 if (_num_alias_types == _max_alias_types) grow_alias_types();
1718 // Add a new alias type.
1719 idx = _num_alias_types++;
1720 _alias_types[idx]->Init(idx, flat);
1721 if (flat == TypeInstPtr::KLASS) alias_type(idx)->set_rewritable(false);
1722 if (flat == TypeAryPtr::RANGE) alias_type(idx)->set_rewritable(false);
1723 if (flat->isa_instptr()) {
1724 if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
1725 && flat->is_instptr()->klass() == env()->Class_klass())
1726 alias_type(idx)->set_rewritable(false);
1727 }
1728 if (flat->isa_aryptr()) {
1729 #ifdef ASSERT
1730 const int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1731 // (T_BYTE has the weakest alignment and size restrictions...)
1732 assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
1733 #endif
1734 if (flat->offset() == TypePtr::OffsetBot) {
1735 alias_type(idx)->set_element(flat->is_aryptr()->elem());
1736 }
1737 }
1738 if (flat->isa_klassptr()) {
1739 if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
1740 alias_type(idx)->set_rewritable(false);
1741 if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
1742 alias_type(idx)->set_rewritable(false);
1743 if (flat->offset() == in_bytes(Klass::access_flags_offset()))
1744 alias_type(idx)->set_rewritable(false);
1745 if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
1746 alias_type(idx)->set_rewritable(false);
1747 }
1748 // %%% (We would like to finalize JavaThread::threadObj_offset(),
1749 // but the base pointer type is not distinctive enough to identify
1750 // references into JavaThread.)
1751
1752 // Check for final fields.
1753 const TypeInstPtr* tinst = flat->isa_instptr();
1754 if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1755 ciField* field;
1756 if (tinst->const_oop() != NULL &&
1757 tinst->klass() == ciEnv::current()->Class_klass() &&
1758 tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
1759 // static field
1760 ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1761 field = k->get_field_by_offset(tinst->offset(), true);
1762 } else {
1763 ciInstanceKlass *k = tinst->klass()->as_instance_klass();
1764 field = k->get_field_by_offset(tinst->offset(), false);
1765 }
1766 assert(field == NULL ||
1767 original_field == NULL ||
1768 (field->holder() == original_field->holder() &&
1769 field->offset() == original_field->offset() &&
1770 field->is_static() == original_field->is_static()), "wrong field?");
1771 // Set field() and is_rewritable() attributes.
1772 if (field != NULL) alias_type(idx)->set_field(field);
1773 }
1774 }
1775
1776 // Fill the cache for next time.
1777 ace->_adr_type = adr_type;
1778 ace->_index = idx;
1779 assert(alias_type(adr_type) == alias_type(idx), "type must be installed");
1780
1781 // Might as well try to fill the cache for the flattened version, too.
1782 AliasCacheEntry* face = probe_alias_cache(flat);
1783 if (face->_adr_type == NULL) {
1784 face->_adr_type = flat;
1785 face->_index = idx;
1786 assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1787 }
1788
1789 return alias_type(idx);
1790 }
1791
1792
1793 Compile::AliasType* Compile::alias_type(ciField* field) {
1794 const TypeOopPtr* t;
1795 if (field->is_static())
1796 t = TypeInstPtr::make(field->holder()->java_mirror());
1797 else
1798 t = TypeOopPtr::make_from_klass_raw(field->holder());
1799 AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1800 assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
1801 return atp;
1802 }
1803
1804
1805 //------------------------------have_alias_type--------------------------------
1806 bool Compile::have_alias_type(const TypePtr* adr_type) {
1807 AliasCacheEntry* ace = probe_alias_cache(adr_type);
1808 if (ace->_adr_type == adr_type) {
1809 return true;
1810 }
1811
1812 // Handle special cases.
1813 if (adr_type == NULL) return true;
1814 if (adr_type == TypePtr::BOTTOM) return true;
1815
1816 return find_alias_type(adr_type, true, NULL) != NULL;
1817 }
1818
1819 //-----------------------------must_alias--------------------------------------
1820 // True if all values of the given address type are in the given alias category.
1821 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1822 if (alias_idx == AliasIdxBot) return true; // the universal category
1823 if (adr_type == NULL) return true; // NULL serves as TypePtr::TOP
1824 if (alias_idx == AliasIdxTop) return false; // the empty category
1825 if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1826
1827 // the only remaining possible overlap is identity
1828 int adr_idx = get_alias_index(adr_type);
1829 assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1830 assert(adr_idx == alias_idx ||
1831 (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1832 && adr_type != TypeOopPtr::BOTTOM),
1833 "should not be testing for overlap with an unsafe pointer");
1834 return adr_idx == alias_idx;
1835 }
1836
1837 //------------------------------can_alias--------------------------------------
1838 // True if any values of the given address type are in the given alias category.
1839 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1840 if (alias_idx == AliasIdxTop) return false; // the empty category
1841 if (adr_type == NULL) return false; // NULL serves as TypePtr::TOP
1842 if (alias_idx == AliasIdxBot) return true; // the universal category
1843 if (adr_type->base() == Type::AnyPtr) return true; // TypePtr::BOTTOM or its twins
1844
1845 // the only remaining possible overlap is identity
1846 int adr_idx = get_alias_index(adr_type);
1847 assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1848 return adr_idx == alias_idx;
1849 }
1850
1851
1852
1853 //---------------------------pop_warm_call-------------------------------------
1854 WarmCallInfo* Compile::pop_warm_call() {
1855 WarmCallInfo* wci = _warm_calls;
1856 if (wci != NULL) _warm_calls = wci->remove_from(wci);
1857 return wci;
1858 }
1859
1860 //----------------------------Inline_Warm--------------------------------------
1861 int Compile::Inline_Warm() {
1862 // If there is room, try to inline some more warm call sites.
1863 // %%% Do a graph index compaction pass when we think we're out of space?
1864 if (!InlineWarmCalls) return 0;
1865
1866 int calls_made_hot = 0;
1867 int room_to_grow = NodeCountInliningCutoff - unique();
1868 int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
1869 int amount_grown = 0;
1870 WarmCallInfo* call;
1871 while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
1872 int est_size = (int)call->size();
1873 if (est_size > (room_to_grow - amount_grown)) {
1874 // This one won't fit anyway. Get rid of it.
1875 call->make_cold();
1876 continue;
1877 }
1878 call->make_hot();
1879 calls_made_hot++;
1880 amount_grown += est_size;
1881 amount_to_grow -= est_size;
1882 }
1883
1884 if (calls_made_hot > 0) set_major_progress();
1885 return calls_made_hot;
1886 }
1887
1888
1889 //----------------------------Finish_Warm--------------------------------------
1890 void Compile::Finish_Warm() {
1891 if (!InlineWarmCalls) return;
1892 if (failing()) return;
1893 if (warm_calls() == NULL) return;
1894
1895 // Clean up loose ends, if we are out of space for inlining.
1896 WarmCallInfo* call;
1897 while ((call = pop_warm_call()) != NULL) {
1898 call->make_cold();
1899 }
1900 }
1901
1902 //---------------------cleanup_loop_predicates-----------------------
1903 // Remove the opaque nodes that protect the predicates so that all unused
1904 // checks and uncommon_traps will be eliminated from the ideal graph
1905 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
1906 if (predicate_count()==0) return;
1907 for (int i = predicate_count(); i > 0; i--) {
1908 Node * n = predicate_opaque1_node(i-1);
1909 assert(n->Opcode() == Op_Opaque1, "must be");
1910 igvn.replace_node(n, n->in(1));
1911 }
1912 assert(predicate_count()==0, "should be clean!");
1913 }
1914
1915 void Compile::add_range_check_cast(Node* n) {
1916 assert(n->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1917 assert(!_range_check_casts->contains(n), "duplicate entry in range check casts");
1918 _range_check_casts->append(n);
1919 }
1920
1921 // Remove all range check dependent CastIINodes.
1922 void Compile::remove_range_check_casts(PhaseIterGVN &igvn) {
1923 for (int i = range_check_cast_count(); i > 0; i--) {
1924 Node* cast = range_check_cast_node(i-1);
1925 assert(cast->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1926 igvn.replace_node(cast, cast->in(1));
1927 }
1928 assert(range_check_cast_count() == 0, "should be empty");
1929 }
1930
1931 // StringOpts and late inlining of string methods
1932 void Compile::inline_string_calls(bool parse_time) {
1933 {
1934 // remove useless nodes to make the usage analysis simpler
1935 ResourceMark rm;
1936 PhaseRemoveUseless pru(initial_gvn(), for_igvn());
1937 }
1938
1939 {
1940 ResourceMark rm;
1941 print_method(PHASE_BEFORE_STRINGOPTS, 3);
1942 PhaseStringOpts pso(initial_gvn(), for_igvn());
1943 print_method(PHASE_AFTER_STRINGOPTS, 3);
1944 }
1945
1946 // now inline anything that we skipped the first time around
1947 if (!parse_time) {
1948 _late_inlines_pos = _late_inlines.length();
1949 }
1950
1951 while (_string_late_inlines.length() > 0) {
1952 CallGenerator* cg = _string_late_inlines.pop();
1953 cg->do_late_inline();
1954 if (failing()) return;
1955 }
1956 _string_late_inlines.trunc_to(0);
1957 }
1958
1959 // Late inlining of boxing methods
1960 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
1961 if (_boxing_late_inlines.length() > 0) {
1962 assert(has_boxed_value(), "inconsistent");
1963
1964 PhaseGVN* gvn = initial_gvn();
1965 set_inlining_incrementally(true);
1966
1967 assert( igvn._worklist.size() == 0, "should be done with igvn" );
1968 for_igvn()->clear();
1969 gvn->replace_with(&igvn);
1970
1971 _late_inlines_pos = _late_inlines.length();
1972
1973 while (_boxing_late_inlines.length() > 0) {
1974 CallGenerator* cg = _boxing_late_inlines.pop();
1975 cg->do_late_inline();
1976 if (failing()) return;
1977 }
1978 _boxing_late_inlines.trunc_to(0);
1979
1980 {
1981 ResourceMark rm;
1982 PhaseRemoveUseless pru(gvn, for_igvn());
1983 }
1984
1985 igvn = PhaseIterGVN(gvn);
1986 igvn.optimize();
1987
1988 set_inlining_progress(false);
1989 set_inlining_incrementally(false);
1990 }
1991 }
1992
1993 void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
1994 assert(IncrementalInline, "incremental inlining should be on");
1995 PhaseGVN* gvn = initial_gvn();
1996
1997 set_inlining_progress(false);
1998 for_igvn()->clear();
1999 gvn->replace_with(&igvn);
2000
2001 int i = 0;
2002
2003 for (; i <_late_inlines.length() && !inlining_progress(); i++) {
2004 CallGenerator* cg = _late_inlines.at(i);
2005 _late_inlines_pos = i+1;
2006 cg->do_late_inline();
2007 if (failing()) return;
2008 }
2009 int j = 0;
2010 for (; i < _late_inlines.length(); i++, j++) {
2011 _late_inlines.at_put(j, _late_inlines.at(i));
2012 }
2013 _late_inlines.trunc_to(j);
2014
2015 {
2016 ResourceMark rm;
2017 PhaseRemoveUseless pru(gvn, for_igvn());
2018 }
2019
2020 igvn = PhaseIterGVN(gvn);
2021 }
2022
2023 // Perform incremental inlining until bound on number of live nodes is reached
2024 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
2025 PhaseGVN* gvn = initial_gvn();
2026
2027 set_inlining_incrementally(true);
2028 set_inlining_progress(true);
2029 uint low_live_nodes = 0;
2030
2031 while(inlining_progress() && _late_inlines.length() > 0) {
2032
2033 if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2034 if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
2035 // PhaseIdealLoop is expensive so we only try it once we are
2036 // out of live nodes and we only try it again if the previous
2037 // helped got the number of nodes down significantly
2038 PhaseIdealLoop ideal_loop( igvn, false, true );
2039 if (failing()) return;
2040 low_live_nodes = live_nodes();
2041 _major_progress = true;
2042 }
2043
2044 if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2045 break;
2046 }
2047 }
2048
2049 inline_incrementally_one(igvn);
2050
2051 if (failing()) return;
2052
2053 igvn.optimize();
2054
2055 if (failing()) return;
2056 }
2057
2058 assert( igvn._worklist.size() == 0, "should be done with igvn" );
2059
2060 if (_string_late_inlines.length() > 0) {
2061 assert(has_stringbuilder(), "inconsistent");
2062 for_igvn()->clear();
2063 initial_gvn()->replace_with(&igvn);
2064
2065 inline_string_calls(false);
2066
2067 if (failing()) return;
2068
2069 {
2070 ResourceMark rm;
2071 PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2072 }
2073
2074 igvn = PhaseIterGVN(gvn);
2075
2076 igvn.optimize();
2077 }
2078
2079 set_inlining_incrementally(false);
2080 }
2081
2082
2083 // Remove edges from "root" to each SafePoint at a backward branch.
2084 // They were inserted during parsing (see add_safepoint()) to make
2085 // infinite loops without calls or exceptions visible to root, i.e.,
2086 // useful.
2087 void Compile::remove_root_to_sfpts_edges() {
2088 Node *r = root();
2089 if (r != NULL) {
2090 for (uint i = r->req(); i < r->len(); ++i) {
2091 Node *n = r->in(i);
2092 if (n != NULL && n->is_SafePoint()) {
2093 r->rm_prec(i);
2094 --i;
2095 }
2096 }
2097 }
2098 }
2099
2100 //------------------------------Optimize---------------------------------------
2101 // Given a graph, optimize it.
2102 void Compile::Optimize() {
2103 TracePhase t1("optimizer", &_t_optimizer, true);
2104
2105 #ifndef PRODUCT
2106 if (env()->break_at_compile()) {
2107 BREAKPOINT;
2108 }
2109
2110 #endif
2111
2112 ResourceMark rm;
2113 int loop_opts_cnt;
2114
2115 NOT_PRODUCT( verify_graph_edges(); )
2116
2117 print_method(PHASE_AFTER_PARSING);
2118
2119 {
2120 // Iterative Global Value Numbering, including ideal transforms
2121 // Initialize IterGVN with types and values from parse-time GVN
2122 PhaseIterGVN igvn(initial_gvn());
2123 {
2124 NOT_PRODUCT( TracePhase t2("iterGVN", &_t_iterGVN, TimeCompiler); )
2125 igvn.optimize();
2126 }
2127
2128 print_method(PHASE_ITER_GVN1, 2);
2129
2130 if (failing()) return;
2131
2132 {
2133 NOT_PRODUCT( TracePhase t2("incrementalInline", &_t_incrInline, TimeCompiler); )
2134 inline_incrementally(igvn);
2135 }
2136
2137 print_method(PHASE_INCREMENTAL_INLINE, 2);
2138
2139 if (failing()) return;
2140
2141 if (eliminate_boxing()) {
2142 NOT_PRODUCT( TracePhase t2("incrementalInline", &_t_incrInline, TimeCompiler); )
2143 // Inline valueOf() methods now.
2144 inline_boxing_calls(igvn);
2145
2146 if (AlwaysIncrementalInline) {
2147 inline_incrementally(igvn);
2148 }
2149
2150 print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
2151
2152 if (failing()) return;
2153 }
2154
2155 // Now that all inlining is over, cut edge from root to loop
2156 // safepoints
2157 remove_root_to_sfpts_edges();
2158
2159 // Remove the speculative part of types and clean up the graph from
2160 // the extra CastPP nodes whose only purpose is to carry them. Do
2161 // that early so that optimizations are not disrupted by the extra
2162 // CastPP nodes.
2163 remove_speculative_types(igvn);
2164
2165 // No more new expensive nodes will be added to the list from here
2166 // so keep only the actual candidates for optimizations.
2167 cleanup_expensive_nodes(igvn);
2168
2169 if (!failing() && RenumberLiveNodes && live_nodes() + NodeLimitFudgeFactor < unique()) {
2170 NOT_PRODUCT(Compile::TracePhase t2("", &_t_renumberLive, TimeCompiler);)
2171 initial_gvn()->replace_with(&igvn);
2172 for_igvn()->clear();
2173 Unique_Node_List new_worklist(C->comp_arena());
2174 {
2175 ResourceMark rm;
2176 PhaseRenumberLive prl = PhaseRenumberLive(initial_gvn(), for_igvn(), &new_worklist);
2177 }
2178 set_for_igvn(&new_worklist);
2179 igvn = PhaseIterGVN(initial_gvn());
2180 igvn.optimize();
2181 }
2182
2183 // Perform escape analysis
2184 if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
2185 if (has_loops()) {
2186 // Cleanup graph (remove dead nodes).
2187 TracePhase t2("idealLoop", &_t_idealLoop, true);
2188 PhaseIdealLoop ideal_loop( igvn, false, true );
2189 if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
2190 if (failing()) return;
2191 }
2192 ConnectionGraph::do_analysis(this, &igvn);
2193
2194 if (failing()) return;
2195
2196 // Optimize out fields loads from scalar replaceable allocations.
2197 igvn.optimize();
2198 print_method(PHASE_ITER_GVN_AFTER_EA, 2);
2199
2200 if (failing()) return;
2201
2202 if (congraph() != NULL && macro_count() > 0) {
2203 NOT_PRODUCT( TracePhase t2("macroEliminate", &_t_macroEliminate, TimeCompiler); )
2204 PhaseMacroExpand mexp(igvn);
2205 mexp.eliminate_macro_nodes();
2206 igvn.set_delay_transform(false);
2207
2208 igvn.optimize();
2209 print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
2210
2211 if (failing()) return;
2212 }
2213 }
2214
2215 // Loop transforms on the ideal graph. Range Check Elimination,
2216 // peeling, unrolling, etc.
2217
2218 // Set loop opts counter
2219 loop_opts_cnt = num_loop_opts();
2220 if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
2221 {
2222 TracePhase t2("idealLoop", &_t_idealLoop, true);
2223 PhaseIdealLoop ideal_loop( igvn, true );
2224 loop_opts_cnt--;
2225 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
2226 if (failing()) return;
2227 }
2228 // Loop opts pass if partial peeling occurred in previous pass
2229 if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
2230 TracePhase t3("idealLoop", &_t_idealLoop, true);
2231 PhaseIdealLoop ideal_loop( igvn, false );
2232 loop_opts_cnt--;
2233 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
2234 if (failing()) return;
2235 }
2236 // Loop opts pass for loop-unrolling before CCP
2237 if(major_progress() && (loop_opts_cnt > 0)) {
2238 TracePhase t4("idealLoop", &_t_idealLoop, true);
2239 PhaseIdealLoop ideal_loop( igvn, false );
2240 loop_opts_cnt--;
2241 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
2242 }
2243 if (!failing()) {
2244 // Verify that last round of loop opts produced a valid graph
2245 NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
2246 PhaseIdealLoop::verify(igvn);
2247 }
2248 }
2249 if (failing()) return;
2250
2251 // Conditional Constant Propagation;
2252 PhaseCCP ccp( &igvn );
2253 assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
2254 {
2255 TracePhase t2("ccp", &_t_ccp, true);
2256 ccp.do_transform();
2257 }
2258 print_method(PHASE_CPP1, 2);
2259
2260 assert( true, "Break here to ccp.dump_old2new_map()");
2261
2262 // Iterative Global Value Numbering, including ideal transforms
2263 {
2264 NOT_PRODUCT( TracePhase t2("iterGVN2", &_t_iterGVN2, TimeCompiler); )
2265 igvn = ccp;
2266 igvn.optimize();
2267 }
2268
2269 print_method(PHASE_ITER_GVN2, 2);
2270
2271 if (failing()) return;
2272
2273 // Loop transforms on the ideal graph. Range Check Elimination,
2274 // peeling, unrolling, etc.
2275 if(loop_opts_cnt > 0) {
2276 debug_only( int cnt = 0; );
2277 while(major_progress() && (loop_opts_cnt > 0)) {
2278 TracePhase t2("idealLoop", &_t_idealLoop, true);
2279 assert( cnt++ < 40, "infinite cycle in loop optimization" );
2280 PhaseIdealLoop ideal_loop( igvn, true);
2281 loop_opts_cnt--;
2282 if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
2283 if (failing()) return;
2284 }
2285 }
2286
2287 {
2288 // Verify that all previous optimizations produced a valid graph
2289 // at least to this point, even if no loop optimizations were done.
2290 NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
2291 PhaseIdealLoop::verify(igvn);
2292 }
2293
2294 if (range_check_cast_count() > 0) {
2295 // No more loop optimizations. Remove all range check dependent CastIINodes.
2296 C->remove_range_check_casts(igvn);
2297 igvn.optimize();
2298 }
2299
2300 {
2301 NOT_PRODUCT( TracePhase t2("macroExpand", &_t_macroExpand, TimeCompiler); )
2302 PhaseMacroExpand mex(igvn);
2303 if (mex.expand_macro_nodes()) {
2304 assert(failing(), "must bail out w/ explicit message");
2305 return;
2306 }
2307 }
2308
2309 } // (End scope of igvn; run destructor if necessary for asserts.)
2310
2311 dump_inlining();
2312 // A method with only infinite loops has no edges entering loops from root
2313 {
2314 NOT_PRODUCT( TracePhase t2("graphReshape", &_t_graphReshaping, TimeCompiler); )
2315 if (final_graph_reshaping()) {
2316 assert(failing(), "must bail out w/ explicit message");
2317 return;
2318 }
2319 }
2320
2321 print_method(PHASE_OPTIMIZE_FINISHED, 2);
2322 }
2323
2324
2325 //------------------------------Code_Gen---------------------------------------
2326 // Given a graph, generate code for it
2327 void Compile::Code_Gen() {
2328 if (failing()) {
2329 return;
2330 }
2331
2332 // Perform instruction selection. You might think we could reclaim Matcher
2333 // memory PDQ, but actually the Matcher is used in generating spill code.
2334 // Internals of the Matcher (including some VectorSets) must remain live
2335 // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
2336 // set a bit in reclaimed memory.
2337
2338 // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2339 // nodes. Mapping is only valid at the root of each matched subtree.
2340 NOT_PRODUCT( verify_graph_edges(); )
2341
2342 Matcher matcher;
2343 _matcher = &matcher;
2344 {
2345 TracePhase t2("matcher", &_t_matcher, true);
2346 matcher.match();
2347 }
2348 // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2349 // nodes. Mapping is only valid at the root of each matched subtree.
2350 NOT_PRODUCT( verify_graph_edges(); )
2351
2352 // If you have too many nodes, or if matching has failed, bail out
2353 check_node_count(0, "out of nodes matching instructions");
2354 if (failing()) {
2355 return;
2356 }
2357
2358 // Build a proper-looking CFG
2359 PhaseCFG cfg(node_arena(), root(), matcher);
2360 _cfg = &cfg;
2361 {
2362 NOT_PRODUCT( TracePhase t2("scheduler", &_t_scheduler, TimeCompiler); )
2363 bool success = cfg.do_global_code_motion();
2364 if (!success) {
2365 return;
2366 }
2367
2368 print_method(PHASE_GLOBAL_CODE_MOTION, 2);
2369 NOT_PRODUCT( verify_graph_edges(); )
2370 debug_only( cfg.verify(); )
2371 }
2372
2373 PhaseChaitin regalloc(unique(), cfg, matcher);
2374 _regalloc = ®alloc;
2375 {
2376 TracePhase t2("regalloc", &_t_registerAllocation, true);
2377 // Perform register allocation. After Chaitin, use-def chains are
2378 // no longer accurate (at spill code) and so must be ignored.
2379 // Node->LRG->reg mappings are still accurate.
2380 _regalloc->Register_Allocate();
2381
2382 // Bail out if the allocator builds too many nodes
2383 if (failing()) {
2384 return;
2385 }
2386 }
2387
2388 // Prior to register allocation we kept empty basic blocks in case the
2389 // the allocator needed a place to spill. After register allocation we
2390 // are not adding any new instructions. If any basic block is empty, we
2391 // can now safely remove it.
2392 {
2393 NOT_PRODUCT( TracePhase t2("blockOrdering", &_t_blockOrdering, TimeCompiler); )
2394 cfg.remove_empty_blocks();
2395 if (do_freq_based_layout()) {
2396 PhaseBlockLayout layout(cfg);
2397 } else {
2398 cfg.set_loop_alignment();
2399 }
2400 cfg.fixup_flow();
2401 }
2402
2403 // Apply peephole optimizations
2404 if( OptoPeephole ) {
2405 NOT_PRODUCT( TracePhase t2("peephole", &_t_peephole, TimeCompiler); )
2406 PhasePeephole peep( _regalloc, cfg);
2407 peep.do_transform();
2408 }
2409
2410 // Do late expand if CPU requires this.
2411 if (Matcher::require_postalloc_expand) {
2412 NOT_PRODUCT(TracePhase t2c("postalloc_expand", &_t_postalloc_expand, true));
2413 cfg.postalloc_expand(_regalloc);
2414 }
2415
2416 // Convert Nodes to instruction bits in a buffer
2417 {
2418 // %%%% workspace merge brought two timers together for one job
2419 TracePhase t2a("output", &_t_output, true);
2420 NOT_PRODUCT( TraceTime t2b(NULL, &_t_codeGeneration, TimeCompiler, false); )
2421 Output();
2422 }
2423
2424 print_method(PHASE_FINAL_CODE);
2425
2426 // He's dead, Jim.
2427 _cfg = (PhaseCFG*)((intptr_t)0xdeadbeef);
2428 _regalloc = (PhaseChaitin*)((intptr_t)0xdeadbeef);
2429 }
2430
2431
2432 //------------------------------dump_asm---------------------------------------
2433 // Dump formatted assembly
2434 #ifndef PRODUCT
2435 void Compile::dump_asm(int *pcs, uint pc_limit) {
2436 bool cut_short = false;
2437 tty->print_cr("#");
2438 tty->print("# "); _tf->dump(); tty->cr();
2439 tty->print_cr("#");
2440
2441 // For all blocks
2442 int pc = 0x0; // Program counter
2443 char starts_bundle = ' ';
2444 _regalloc->dump_frame();
2445
2446 Node *n = NULL;
2447 for (uint i = 0; i < _cfg->number_of_blocks(); i++) {
2448 if (VMThread::should_terminate()) {
2449 cut_short = true;
2450 break;
2451 }
2452 Block* block = _cfg->get_block(i);
2453 if (block->is_connector() && !Verbose) {
2454 continue;
2455 }
2456 n = block->head();
2457 if (pcs && n->_idx < pc_limit) {
2458 tty->print("%3.3x ", pcs[n->_idx]);
2459 } else {
2460 tty->print(" ");
2461 }
2462 block->dump_head(_cfg);
2463 if (block->is_connector()) {
2464 tty->print_cr(" # Empty connector block");
2465 } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
2466 tty->print_cr(" # Block is sole successor of call");
2467 }
2468
2469 // For all instructions
2470 Node *delay = NULL;
2471 for (uint j = 0; j < block->number_of_nodes(); j++) {
2472 if (VMThread::should_terminate()) {
2473 cut_short = true;
2474 break;
2475 }
2476 n = block->get_node(j);
2477 if (valid_bundle_info(n)) {
2478 Bundle* bundle = node_bundling(n);
2479 if (bundle->used_in_unconditional_delay()) {
2480 delay = n;
2481 continue;
2482 }
2483 if (bundle->starts_bundle()) {
2484 starts_bundle = '+';
2485 }
2486 }
2487
2488 if (WizardMode) {
2489 n->dump();
2490 }
2491
2492 if( !n->is_Region() && // Dont print in the Assembly
2493 !n->is_Phi() && // a few noisely useless nodes
2494 !n->is_Proj() &&
2495 !n->is_MachTemp() &&
2496 !n->is_SafePointScalarObject() &&
2497 !n->is_Catch() && // Would be nice to print exception table targets
2498 !n->is_MergeMem() && // Not very interesting
2499 !n->is_top() && // Debug info table constants
2500 !(n->is_Con() && !n->is_Mach())// Debug info table constants
2501 ) {
2502 if (pcs && n->_idx < pc_limit)
2503 tty->print("%3.3x", pcs[n->_idx]);
2504 else
2505 tty->print(" ");
2506 tty->print(" %c ", starts_bundle);
2507 starts_bundle = ' ';
2508 tty->print("\t");
2509 n->format(_regalloc, tty);
2510 tty->cr();
2511 }
2512
2513 // If we have an instruction with a delay slot, and have seen a delay,
2514 // then back up and print it
2515 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
2516 assert(delay != NULL, "no unconditional delay instruction");
2517 if (WizardMode) delay->dump();
2518
2519 if (node_bundling(delay)->starts_bundle())
2520 starts_bundle = '+';
2521 if (pcs && n->_idx < pc_limit)
2522 tty->print("%3.3x", pcs[n->_idx]);
2523 else
2524 tty->print(" ");
2525 tty->print(" %c ", starts_bundle);
2526 starts_bundle = ' ';
2527 tty->print("\t");
2528 delay->format(_regalloc, tty);
2529 tty->cr();
2530 delay = NULL;
2531 }
2532
2533 // Dump the exception table as well
2534 if( n->is_Catch() && (Verbose || WizardMode) ) {
2535 // Print the exception table for this offset
2536 _handler_table.print_subtable_for(pc);
2537 }
2538 }
2539
2540 if (pcs && n->_idx < pc_limit)
2541 tty->print_cr("%3.3x", pcs[n->_idx]);
2542 else
2543 tty->cr();
2544
2545 assert(cut_short || delay == NULL, "no unconditional delay branch");
2546
2547 } // End of per-block dump
2548 tty->cr();
2549
2550 if (cut_short) tty->print_cr("*** disassembly is cut short ***");
2551 }
2552 #endif
2553
2554 //------------------------------Final_Reshape_Counts---------------------------
2555 // This class defines counters to help identify when a method
2556 // may/must be executed using hardware with only 24-bit precision.
2557 struct Final_Reshape_Counts : public StackObj {
2558 int _call_count; // count non-inlined 'common' calls
2559 int _float_count; // count float ops requiring 24-bit precision
2560 int _double_count; // count double ops requiring more precision
2561 int _java_call_count; // count non-inlined 'java' calls
2562 int _inner_loop_count; // count loops which need alignment
2563 VectorSet _visited; // Visitation flags
2564 Node_List _tests; // Set of IfNodes & PCTableNodes
2565
2566 Final_Reshape_Counts() :
2567 _call_count(0), _float_count(0), _double_count(0),
2568 _java_call_count(0), _inner_loop_count(0),
2569 _visited( Thread::current()->resource_area() ) { }
2570
2571 void inc_call_count () { _call_count ++; }
2572 void inc_float_count () { _float_count ++; }
2573 void inc_double_count() { _double_count++; }
2574 void inc_java_call_count() { _java_call_count++; }
2575 void inc_inner_loop_count() { _inner_loop_count++; }
2576
2577 int get_call_count () const { return _call_count ; }
2578 int get_float_count () const { return _float_count ; }
2579 int get_double_count() const { return _double_count; }
2580 int get_java_call_count() const { return _java_call_count; }
2581 int get_inner_loop_count() const { return _inner_loop_count; }
2582 };
2583
2584 #ifdef ASSERT
2585 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
2586 ciInstanceKlass *k = tp->klass()->as_instance_klass();
2587 // Make sure the offset goes inside the instance layout.
2588 return k->contains_field_offset(tp->offset());
2589 // Note that OffsetBot and OffsetTop are very negative.
2590 }
2591 #endif
2592
2593 // Eliminate trivially redundant StoreCMs and accumulate their
2594 // precedence edges.
2595 void Compile::eliminate_redundant_card_marks(Node* n) {
2596 assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
2597 if (n->in(MemNode::Address)->outcnt() > 1) {
2598 // There are multiple users of the same address so it might be
2599 // possible to eliminate some of the StoreCMs
2600 Node* mem = n->in(MemNode::Memory);
2601 Node* adr = n->in(MemNode::Address);
2602 Node* val = n->in(MemNode::ValueIn);
2603 Node* prev = n;
2604 bool done = false;
2605 // Walk the chain of StoreCMs eliminating ones that match. As
2606 // long as it's a chain of single users then the optimization is
2607 // safe. Eliminating partially redundant StoreCMs would require
2608 // cloning copies down the other paths.
2609 while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
2610 if (adr == mem->in(MemNode::Address) &&
2611 val == mem->in(MemNode::ValueIn)) {
2612 // redundant StoreCM
2613 if (mem->req() > MemNode::OopStore) {
2614 // Hasn't been processed by this code yet.
2615 n->add_prec(mem->in(MemNode::OopStore));
2616 } else {
2617 // Already converted to precedence edge
2618 for (uint i = mem->req(); i < mem->len(); i++) {
2619 // Accumulate any precedence edges
2620 if (mem->in(i) != NULL) {
2621 n->add_prec(mem->in(i));
2622 }
2623 }
2624 // Everything above this point has been processed.
2625 done = true;
2626 }
2627 // Eliminate the previous StoreCM
2628 prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
2629 assert(mem->outcnt() == 0, "should be dead");
2630 mem->disconnect_inputs(NULL, this);
2631 } else {
2632 prev = mem;
2633 }
2634 mem = prev->in(MemNode::Memory);
2635 }
2636 }
2637 }
2638
2639 //------------------------------final_graph_reshaping_impl----------------------
2640 // Implement items 1-5 from final_graph_reshaping below.
2641 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
2642
2643 if ( n->outcnt() == 0 ) return; // dead node
2644 uint nop = n->Opcode();
2645
2646 // Check for 2-input instruction with "last use" on right input.
2647 // Swap to left input. Implements item (2).
2648 if( n->req() == 3 && // two-input instruction
2649 n->in(1)->outcnt() > 1 && // left use is NOT a last use
2650 (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
2651 n->in(2)->outcnt() == 1 &&// right use IS a last use
2652 !n->in(2)->is_Con() ) { // right use is not a constant
2653 // Check for commutative opcode
2654 switch( nop ) {
2655 case Op_AddI: case Op_AddF: case Op_AddD: case Op_AddL:
2656 case Op_MaxI: case Op_MinI:
2657 case Op_MulI: case Op_MulF: case Op_MulD: case Op_MulL:
2658 case Op_AndL: case Op_XorL: case Op_OrL:
2659 case Op_AndI: case Op_XorI: case Op_OrI: {
2660 // Move "last use" input to left by swapping inputs
2661 n->swap_edges(1, 2);
2662 break;
2663 }
2664 default:
2665 break;
2666 }
2667 }
2668
2669 #ifdef ASSERT
2670 if( n->is_Mem() ) {
2671 int alias_idx = get_alias_index(n->as_Mem()->adr_type());
2672 assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
2673 // oop will be recorded in oop map if load crosses safepoint
2674 n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
2675 LoadNode::is_immutable_value(n->in(MemNode::Address))),
2676 "raw memory operations should have control edge");
2677 }
2678 if (n->is_MemBar()) {
2679 MemBarNode* mb = n->as_MemBar();
2680 if (mb->trailing_store() || mb->trailing_load_store()) {
2681 assert(mb->leading_membar()->trailing_membar() == mb, "bad membar pair");
2682 Node* mem = mb->in(MemBarNode::Precedent);
2683 assert((mb->trailing_store() && mem->is_Store() && mem->as_Store()->is_release()) ||
2684 (mb->trailing_load_store() && mem->is_LoadStore()), "missing mem op");
2685 } else if (mb->leading()) {
2686 assert(mb->trailing_membar()->leading_membar() == mb, "bad membar pair");
2687 }
2688 }
2689 #endif
2690 // Count FPU ops and common calls, implements item (3)
2691 switch( nop ) {
2692 // Count all float operations that may use FPU
2693 case Op_AddF:
2694 case Op_SubF:
2695 case Op_MulF:
2696 case Op_DivF:
2697 case Op_NegF:
2698 case Op_ModF:
2699 case Op_ConvI2F:
2700 case Op_ConF:
2701 case Op_CmpF:
2702 case Op_CmpF3:
2703 // case Op_ConvL2F: // longs are split into 32-bit halves
2704 frc.inc_float_count();
2705 break;
2706
2707 case Op_ConvF2D:
2708 case Op_ConvD2F:
2709 frc.inc_float_count();
2710 frc.inc_double_count();
2711 break;
2712
2713 // Count all double operations that may use FPU
2714 case Op_AddD:
2715 case Op_SubD:
2716 case Op_MulD:
2717 case Op_DivD:
2718 case Op_NegD:
2719 case Op_ModD:
2720 case Op_ConvI2D:
2721 case Op_ConvD2I:
2722 // case Op_ConvL2D: // handled by leaf call
2723 // case Op_ConvD2L: // handled by leaf call
2724 case Op_ConD:
2725 case Op_CmpD:
2726 case Op_CmpD3:
2727 frc.inc_double_count();
2728 break;
2729 case Op_Opaque1: // Remove Opaque Nodes before matching
2730 case Op_Opaque2: // Remove Opaque Nodes before matching
2731 case Op_Opaque3:
2732 n->subsume_by(n->in(1), this);
2733 break;
2734 case Op_CallStaticJava:
2735 case Op_CallJava:
2736 case Op_CallDynamicJava:
2737 frc.inc_java_call_count(); // Count java call site;
2738 case Op_CallRuntime:
2739 case Op_CallLeaf:
2740 case Op_CallLeafNoFP: {
2741 assert( n->is_Call(), "" );
2742 CallNode *call = n->as_Call();
2743 // Count call sites where the FP mode bit would have to be flipped.
2744 // Do not count uncommon runtime calls:
2745 // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
2746 // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
2747 if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
2748 frc.inc_call_count(); // Count the call site
2749 } else { // See if uncommon argument is shared
2750 Node *n = call->in(TypeFunc::Parms);
2751 int nop = n->Opcode();
2752 // Clone shared simple arguments to uncommon calls, item (1).
2753 if( n->outcnt() > 1 &&
2754 !n->is_Proj() &&
2755 nop != Op_CreateEx &&
2756 nop != Op_CheckCastPP &&
2757 nop != Op_DecodeN &&
2758 nop != Op_DecodeNKlass &&
2759 !n->is_Mem() ) {
2760 Node *x = n->clone();
2761 call->set_req( TypeFunc::Parms, x );
2762 }
2763 }
2764 break;
2765 }
2766
2767 case Op_StoreD:
2768 case Op_LoadD:
2769 case Op_LoadD_unaligned:
2770 frc.inc_double_count();
2771 goto handle_mem;
2772 case Op_StoreF:
2773 case Op_LoadF:
2774 frc.inc_float_count();
2775 goto handle_mem;
2776
2777 case Op_StoreCM:
2778 {
2779 // Convert OopStore dependence into precedence edge
2780 Node* prec = n->in(MemNode::OopStore);
2781 n->del_req(MemNode::OopStore);
2782 n->add_prec(prec);
2783 eliminate_redundant_card_marks(n);
2784 }
2785
2786 // fall through
2787
2788 case Op_StoreB:
2789 case Op_StoreC:
2790 case Op_StorePConditional:
2791 case Op_StoreI:
2792 case Op_StoreL:
2793 case Op_StoreIConditional:
2794 case Op_StoreLConditional:
2795 case Op_CompareAndSwapI:
2796 case Op_CompareAndSwapL:
2797 case Op_CompareAndSwapP:
2798 case Op_CompareAndSwapN:
2799 case Op_GetAndAddI:
2800 case Op_GetAndAddL:
2801 case Op_GetAndSetI:
2802 case Op_GetAndSetL:
2803 case Op_GetAndSetP:
2804 case Op_GetAndSetN:
2805 case Op_StoreP:
2806 case Op_StoreN:
2807 case Op_StoreNKlass:
2808 case Op_LoadB:
2809 case Op_LoadUB:
2810 case Op_LoadUS:
2811 case Op_LoadI:
2812 case Op_LoadKlass:
2813 case Op_LoadNKlass:
2814 case Op_LoadL:
2815 case Op_LoadL_unaligned:
2816 case Op_LoadPLocked:
2817 case Op_LoadP:
2818 case Op_LoadN:
2819 case Op_LoadRange:
2820 case Op_LoadS: {
2821 handle_mem:
2822 #ifdef ASSERT
2823 if( VerifyOptoOopOffsets ) {
2824 assert( n->is_Mem(), "" );
2825 MemNode *mem = (MemNode*)n;
2826 // Check to see if address types have grounded out somehow.
2827 const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
2828 assert( !tp || oop_offset_is_sane(tp), "" );
2829 }
2830 #endif
2831 break;
2832 }
2833
2834 case Op_AddP: { // Assert sane base pointers
2835 Node *addp = n->in(AddPNode::Address);
2836 assert( !addp->is_AddP() ||
2837 addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
2838 addp->in(AddPNode::Base) == n->in(AddPNode::Base),
2839 "Base pointers must match" );
2840 #ifdef _LP64
2841 if ((UseCompressedOops || UseCompressedClassPointers) &&
2842 addp->Opcode() == Op_ConP &&
2843 addp == n->in(AddPNode::Base) &&
2844 n->in(AddPNode::Offset)->is_Con()) {
2845 // Use addressing with narrow klass to load with offset on x86.
2846 // On sparc loading 32-bits constant and decoding it have less
2847 // instructions (4) then load 64-bits constant (7).
2848 // Do this transformation here since IGVN will convert ConN back to ConP.
2849 const Type* t = addp->bottom_type();
2850 if (t->isa_oopptr() || t->isa_klassptr()) {
2851 Node* nn = NULL;
2852
2853 int op = t->isa_oopptr() ? Op_ConN : Op_ConNKlass;
2854
2855 // Look for existing ConN node of the same exact type.
2856 Node* r = root();
2857 uint cnt = r->outcnt();
2858 for (uint i = 0; i < cnt; i++) {
2859 Node* m = r->raw_out(i);
2860 if (m!= NULL && m->Opcode() == op &&
2861 m->bottom_type()->make_ptr() == t) {
2862 nn = m;
2863 break;
2864 }
2865 }
2866 if (nn != NULL) {
2867 // Decode a narrow oop to match address
2868 // [R12 + narrow_oop_reg<<3 + offset]
2869 if (t->isa_oopptr()) {
2870 nn = new (this) DecodeNNode(nn, t);
2871 } else {
2872 nn = new (this) DecodeNKlassNode(nn, t);
2873 }
2874 n->set_req(AddPNode::Base, nn);
2875 n->set_req(AddPNode::Address, nn);
2876 if (addp->outcnt() == 0) {
2877 addp->disconnect_inputs(NULL, this);
2878 }
2879 }
2880 }
2881 }
2882 #endif
2883 break;
2884 }
2885
2886 #ifdef _LP64
2887 case Op_CastPP:
2888 if (n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
2889 Node* in1 = n->in(1);
2890 const Type* t = n->bottom_type();
2891 Node* new_in1 = in1->clone();
2892 new_in1->as_DecodeN()->set_type(t);
2893
2894 if (!Matcher::narrow_oop_use_complex_address()) {
2895 //
2896 // x86, ARM and friends can handle 2 adds in addressing mode
2897 // and Matcher can fold a DecodeN node into address by using
2898 // a narrow oop directly and do implicit NULL check in address:
2899 //
2900 // [R12 + narrow_oop_reg<<3 + offset]
2901 // NullCheck narrow_oop_reg
2902 //
2903 // On other platforms (Sparc) we have to keep new DecodeN node and
2904 // use it to do implicit NULL check in address:
2905 //
2906 // decode_not_null narrow_oop_reg, base_reg
2907 // [base_reg + offset]
2908 // NullCheck base_reg
2909 //
2910 // Pin the new DecodeN node to non-null path on these platform (Sparc)
2911 // to keep the information to which NULL check the new DecodeN node
2912 // corresponds to use it as value in implicit_null_check().
2913 //
2914 new_in1->set_req(0, n->in(0));
2915 }
2916
2917 n->subsume_by(new_in1, this);
2918 if (in1->outcnt() == 0) {
2919 in1->disconnect_inputs(NULL, this);
2920 }
2921 }
2922 break;
2923
2924 case Op_CmpP:
2925 // Do this transformation here to preserve CmpPNode::sub() and
2926 // other TypePtr related Ideal optimizations (for example, ptr nullness).
2927 if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
2928 Node* in1 = n->in(1);
2929 Node* in2 = n->in(2);
2930 if (!in1->is_DecodeNarrowPtr()) {
2931 in2 = in1;
2932 in1 = n->in(2);
2933 }
2934 assert(in1->is_DecodeNarrowPtr(), "sanity");
2935
2936 Node* new_in2 = NULL;
2937 if (in2->is_DecodeNarrowPtr()) {
2938 assert(in2->Opcode() == in1->Opcode(), "must be same node type");
2939 new_in2 = in2->in(1);
2940 } else if (in2->Opcode() == Op_ConP) {
2941 const Type* t = in2->bottom_type();
2942 if (t == TypePtr::NULL_PTR) {
2943 assert(in1->is_DecodeN(), "compare klass to null?");
2944 // Don't convert CmpP null check into CmpN if compressed
2945 // oops implicit null check is not generated.
2946 // This will allow to generate normal oop implicit null check.
2947 if (Matcher::gen_narrow_oop_implicit_null_checks())
2948 new_in2 = ConNode::make(this, TypeNarrowOop::NULL_PTR);
2949 //
2950 // This transformation together with CastPP transformation above
2951 // will generated code for implicit NULL checks for compressed oops.
2952 //
2953 // The original code after Optimize()
2954 //
2955 // LoadN memory, narrow_oop_reg
2956 // decode narrow_oop_reg, base_reg
2957 // CmpP base_reg, NULL
2958 // CastPP base_reg // NotNull
2959 // Load [base_reg + offset], val_reg
2960 //
2961 // after these transformations will be
2962 //
2963 // LoadN memory, narrow_oop_reg
2964 // CmpN narrow_oop_reg, NULL
2965 // decode_not_null narrow_oop_reg, base_reg
2966 // Load [base_reg + offset], val_reg
2967 //
2968 // and the uncommon path (== NULL) will use narrow_oop_reg directly
2969 // since narrow oops can be used in debug info now (see the code in
2970 // final_graph_reshaping_walk()).
2971 //
2972 // At the end the code will be matched to
2973 // on x86:
2974 //
2975 // Load_narrow_oop memory, narrow_oop_reg
2976 // Load [R12 + narrow_oop_reg<<3 + offset], val_reg
2977 // NullCheck narrow_oop_reg
2978 //
2979 // and on sparc:
2980 //
2981 // Load_narrow_oop memory, narrow_oop_reg
2982 // decode_not_null narrow_oop_reg, base_reg
2983 // Load [base_reg + offset], val_reg
2984 // NullCheck base_reg
2985 //
2986 } else if (t->isa_oopptr()) {
2987 new_in2 = ConNode::make(this, t->make_narrowoop());
2988 } else if (t->isa_klassptr()) {
2989 new_in2 = ConNode::make(this, t->make_narrowklass());
2990 }
2991 }
2992 if (new_in2 != NULL) {
2993 Node* cmpN = new (this) CmpNNode(in1->in(1), new_in2);
2994 n->subsume_by(cmpN, this);
2995 if (in1->outcnt() == 0) {
2996 in1->disconnect_inputs(NULL, this);
2997 }
2998 if (in2->outcnt() == 0) {
2999 in2->disconnect_inputs(NULL, this);
3000 }
3001 }
3002 }
3003 break;
3004
3005 case Op_DecodeN:
3006 case Op_DecodeNKlass:
3007 assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
3008 // DecodeN could be pinned when it can't be fold into
3009 // an address expression, see the code for Op_CastPP above.
3010 assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
3011 break;
3012
3013 case Op_EncodeP:
3014 case Op_EncodePKlass: {
3015 Node* in1 = n->in(1);
3016 if (in1->is_DecodeNarrowPtr()) {
3017 n->subsume_by(in1->in(1), this);
3018 } else if (in1->Opcode() == Op_ConP) {
3019 const Type* t = in1->bottom_type();
3020 if (t == TypePtr::NULL_PTR) {
3021 assert(t->isa_oopptr(), "null klass?");
3022 n->subsume_by(ConNode::make(this, TypeNarrowOop::NULL_PTR), this);
3023 } else if (t->isa_oopptr()) {
3024 n->subsume_by(ConNode::make(this, t->make_narrowoop()), this);
3025 } else if (t->isa_klassptr()) {
3026 n->subsume_by(ConNode::make(this, t->make_narrowklass()), this);
3027 }
3028 }
3029 if (in1->outcnt() == 0) {
3030 in1->disconnect_inputs(NULL, this);
3031 }
3032 break;
3033 }
3034
3035 case Op_Proj: {
3036 if (OptimizeStringConcat) {
3037 ProjNode* p = n->as_Proj();
3038 if (p->_is_io_use) {
3039 // Separate projections were used for the exception path which
3040 // are normally removed by a late inline. If it wasn't inlined
3041 // then they will hang around and should just be replaced with
3042 // the original one.
3043 Node* proj = NULL;
3044 // Replace with just one
3045 for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
3046 Node *use = i.get();
3047 if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
3048 proj = use;
3049 break;
3050 }
3051 }
3052 assert(proj != NULL || p->_con == TypeFunc::I_O, "io may be dropped at an infinite loop");
3053 if (proj != NULL) {
3054 p->subsume_by(proj, this);
3055 }
3056 }
3057 }
3058 break;
3059 }
3060
3061 case Op_Phi:
3062 if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
3063 // The EncodeP optimization may create Phi with the same edges
3064 // for all paths. It is not handled well by Register Allocator.
3065 Node* unique_in = n->in(1);
3066 assert(unique_in != NULL, "");
3067 uint cnt = n->req();
3068 for (uint i = 2; i < cnt; i++) {
3069 Node* m = n->in(i);
3070 assert(m != NULL, "");
3071 if (unique_in != m)
3072 unique_in = NULL;
3073 }
3074 if (unique_in != NULL) {
3075 n->subsume_by(unique_in, this);
3076 }
3077 }
3078 break;
3079
3080 #endif
3081
3082 #ifdef ASSERT
3083 case Op_CastII:
3084 // Verify that all range check dependent CastII nodes were removed.
3085 if (n->isa_CastII()->has_range_check()) {
3086 n->dump(3);
3087 assert(false, "Range check dependent CastII node was not removed");
3088 }
3089 break;
3090 #endif
3091
3092 case Op_ModI:
3093 if (UseDivMod) {
3094 // Check if a%b and a/b both exist
3095 Node* d = n->find_similar(Op_DivI);
3096 if (d) {
3097 // Replace them with a fused divmod if supported
3098 if (Matcher::has_match_rule(Op_DivModI)) {
3099 DivModINode* divmod = DivModINode::make(this, n);
3100 d->subsume_by(divmod->div_proj(), this);
3101 n->subsume_by(divmod->mod_proj(), this);
3102 } else {
3103 // replace a%b with a-((a/b)*b)
3104 Node* mult = new (this) MulINode(d, d->in(2));
3105 Node* sub = new (this) SubINode(d->in(1), mult);
3106 n->subsume_by(sub, this);
3107 }
3108 }
3109 }
3110 break;
3111
3112 case Op_ModL:
3113 if (UseDivMod) {
3114 // Check if a%b and a/b both exist
3115 Node* d = n->find_similar(Op_DivL);
3116 if (d) {
3117 // Replace them with a fused divmod if supported
3118 if (Matcher::has_match_rule(Op_DivModL)) {
3119 DivModLNode* divmod = DivModLNode::make(this, n);
3120 d->subsume_by(divmod->div_proj(), this);
3121 n->subsume_by(divmod->mod_proj(), this);
3122 } else {
3123 // replace a%b with a-((a/b)*b)
3124 Node* mult = new (this) MulLNode(d, d->in(2));
3125 Node* sub = new (this) SubLNode(d->in(1), mult);
3126 n->subsume_by(sub, this);
3127 }
3128 }
3129 }
3130 break;
3131
3132 case Op_LoadVector:
3133 case Op_StoreVector:
3134 break;
3135
3136 case Op_PackB:
3137 case Op_PackS:
3138 case Op_PackI:
3139 case Op_PackF:
3140 case Op_PackL:
3141 case Op_PackD:
3142 if (n->req()-1 > 2) {
3143 // Replace many operand PackNodes with a binary tree for matching
3144 PackNode* p = (PackNode*) n;
3145 Node* btp = p->binary_tree_pack(this, 1, n->req());
3146 n->subsume_by(btp, this);
3147 }
3148 break;
3149 case Op_Loop:
3150 case Op_CountedLoop:
3151 if (n->as_Loop()->is_inner_loop()) {
3152 frc.inc_inner_loop_count();
3153 }
3154 break;
3155 case Op_LShiftI:
3156 case Op_RShiftI:
3157 case Op_URShiftI:
3158 case Op_LShiftL:
3159 case Op_RShiftL:
3160 case Op_URShiftL:
3161 if (Matcher::need_masked_shift_count) {
3162 // The cpu's shift instructions don't restrict the count to the
3163 // lower 5/6 bits. We need to do the masking ourselves.
3164 Node* in2 = n->in(2);
3165 juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
3166 const TypeInt* t = in2->find_int_type();
3167 if (t != NULL && t->is_con()) {
3168 juint shift = t->get_con();
3169 if (shift > mask) { // Unsigned cmp
3170 n->set_req(2, ConNode::make(this, TypeInt::make(shift & mask)));
3171 }
3172 } else {
3173 if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
3174 Node* shift = new (this) AndINode(in2, ConNode::make(this, TypeInt::make(mask)));
3175 n->set_req(2, shift);
3176 }
3177 }
3178 if (in2->outcnt() == 0) { // Remove dead node
3179 in2->disconnect_inputs(NULL, this);
3180 }
3181 }
3182 break;
3183 case Op_MemBarStoreStore:
3184 case Op_MemBarRelease:
3185 // Break the link with AllocateNode: it is no longer useful and
3186 // confuses register allocation.
3187 if (n->req() > MemBarNode::Precedent) {
3188 n->set_req(MemBarNode::Precedent, top());
3189 }
3190 break;
3191 default:
3192 assert( !n->is_Call(), "" );
3193 assert( !n->is_Mem(), "" );
3194 assert( nop != Op_ProfileBoolean, "should be eliminated during IGVN");
3195 break;
3196 }
3197
3198 // Collect CFG split points
3199 if (n->is_MultiBranch())
3200 frc._tests.push(n);
3201 }
3202
3203 //------------------------------final_graph_reshaping_walk---------------------
3204 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
3205 // requires that the walk visits a node's inputs before visiting the node.
3206 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
3207 ResourceArea *area = Thread::current()->resource_area();
3208 Unique_Node_List sfpt(area);
3209
3210 frc._visited.set(root->_idx); // first, mark node as visited
3211 uint cnt = root->req();
3212 Node *n = root;
3213 uint i = 0;
3214 while (true) {
3215 if (i < cnt) {
3216 // Place all non-visited non-null inputs onto stack
3217 Node* m = n->in(i);
3218 ++i;
3219 if (m != NULL && !frc._visited.test_set(m->_idx)) {
3220 if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL) {
3221 // compute worst case interpreter size in case of a deoptimization
3222 update_interpreter_frame_size(m->as_SafePoint()->jvms()->interpreter_frame_size());
3223
3224 sfpt.push(m);
3225 }
3226 cnt = m->req();
3227 nstack.push(n, i); // put on stack parent and next input's index
3228 n = m;
3229 i = 0;
3230 }
3231 } else {
3232 // Now do post-visit work
3233 final_graph_reshaping_impl( n, frc );
3234 if (nstack.is_empty())
3235 break; // finished
3236 n = nstack.node(); // Get node from stack
3237 cnt = n->req();
3238 i = nstack.index();
3239 nstack.pop(); // Shift to the next node on stack
3240 }
3241 }
3242
3243 // Skip next transformation if compressed oops are not used.
3244 if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
3245 (!UseCompressedOops && !UseCompressedClassPointers))
3246 return;
3247
3248 // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
3249 // It could be done for an uncommon traps or any safepoints/calls
3250 // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
3251 while (sfpt.size() > 0) {
3252 n = sfpt.pop();
3253 JVMState *jvms = n->as_SafePoint()->jvms();
3254 assert(jvms != NULL, "sanity");
3255 int start = jvms->debug_start();
3256 int end = n->req();
3257 bool is_uncommon = (n->is_CallStaticJava() &&
3258 n->as_CallStaticJava()->uncommon_trap_request() != 0);
3259 for (int j = start; j < end; j++) {
3260 Node* in = n->in(j);
3261 if (in->is_DecodeNarrowPtr()) {
3262 bool safe_to_skip = true;
3263 if (!is_uncommon ) {
3264 // Is it safe to skip?
3265 for (uint i = 0; i < in->outcnt(); i++) {
3266 Node* u = in->raw_out(i);
3267 if (!u->is_SafePoint() ||
3268 u->is_Call() && u->as_Call()->has_non_debug_use(n)) {
3269 safe_to_skip = false;
3270 }
3271 }
3272 }
3273 if (safe_to_skip) {
3274 n->set_req(j, in->in(1));
3275 }
3276 if (in->outcnt() == 0) {
3277 in->disconnect_inputs(NULL, this);
3278 }
3279 }
3280 }
3281 }
3282 }
3283
3284 //------------------------------final_graph_reshaping--------------------------
3285 // Final Graph Reshaping.
3286 //
3287 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
3288 // and not commoned up and forced early. Must come after regular
3289 // optimizations to avoid GVN undoing the cloning. Clone constant
3290 // inputs to Loop Phis; these will be split by the allocator anyways.
3291 // Remove Opaque nodes.
3292 // (2) Move last-uses by commutative operations to the left input to encourage
3293 // Intel update-in-place two-address operations and better register usage
3294 // on RISCs. Must come after regular optimizations to avoid GVN Ideal
3295 // calls canonicalizing them back.
3296 // (3) Count the number of double-precision FP ops, single-precision FP ops
3297 // and call sites. On Intel, we can get correct rounding either by
3298 // forcing singles to memory (requires extra stores and loads after each
3299 // FP bytecode) or we can set a rounding mode bit (requires setting and
3300 // clearing the mode bit around call sites). The mode bit is only used
3301 // if the relative frequency of single FP ops to calls is low enough.
3302 // This is a key transform for SPEC mpeg_audio.
3303 // (4) Detect infinite loops; blobs of code reachable from above but not
3304 // below. Several of the Code_Gen algorithms fail on such code shapes,
3305 // so we simply bail out. Happens a lot in ZKM.jar, but also happens
3306 // from time to time in other codes (such as -Xcomp finalizer loops, etc).
3307 // Detection is by looking for IfNodes where only 1 projection is
3308 // reachable from below or CatchNodes missing some targets.
3309 // (5) Assert for insane oop offsets in debug mode.
3310
3311 bool Compile::final_graph_reshaping() {
3312 // an infinite loop may have been eliminated by the optimizer,
3313 // in which case the graph will be empty.
3314 if (root()->req() == 1) {
3315 record_method_not_compilable("trivial infinite loop");
3316 return true;
3317 }
3318
3319 // Expensive nodes have their control input set to prevent the GVN
3320 // from freely commoning them. There's no GVN beyond this point so
3321 // no need to keep the control input. We want the expensive nodes to
3322 // be freely moved to the least frequent code path by gcm.
3323 assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
3324 for (int i = 0; i < expensive_count(); i++) {
3325 _expensive_nodes->at(i)->set_req(0, NULL);
3326 }
3327
3328 Final_Reshape_Counts frc;
3329
3330 // Visit everybody reachable!
3331 // Allocate stack of size C->live_nodes()/2 to avoid frequent realloc
3332 Node_Stack nstack(live_nodes() >> 1);
3333 final_graph_reshaping_walk(nstack, root(), frc);
3334
3335 // Check for unreachable (from below) code (i.e., infinite loops).
3336 for( uint i = 0; i < frc._tests.size(); i++ ) {
3337 MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
3338 // Get number of CFG targets.
3339 // Note that PCTables include exception targets after calls.
3340 uint required_outcnt = n->required_outcnt();
3341 if (n->outcnt() != required_outcnt) {
3342 // Check for a few special cases. Rethrow Nodes never take the
3343 // 'fall-thru' path, so expected kids is 1 less.
3344 if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
3345 if (n->in(0)->in(0)->is_Call()) {
3346 CallNode *call = n->in(0)->in(0)->as_Call();
3347 if (call->entry_point() == OptoRuntime::rethrow_stub()) {
3348 required_outcnt--; // Rethrow always has 1 less kid
3349 } else if (call->req() > TypeFunc::Parms &&
3350 call->is_CallDynamicJava()) {
3351 // Check for null receiver. In such case, the optimizer has
3352 // detected that the virtual call will always result in a null
3353 // pointer exception. The fall-through projection of this CatchNode
3354 // will not be populated.
3355 Node *arg0 = call->in(TypeFunc::Parms);
3356 if (arg0->is_Type() &&
3357 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
3358 required_outcnt--;
3359 }
3360 } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
3361 call->req() > TypeFunc::Parms+1 &&
3362 call->is_CallStaticJava()) {
3363 // Check for negative array length. In such case, the optimizer has
3364 // detected that the allocation attempt will always result in an
3365 // exception. There is no fall-through projection of this CatchNode .
3366 Node *arg1 = call->in(TypeFunc::Parms+1);
3367 if (arg1->is_Type() &&
3368 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
3369 required_outcnt--;
3370 }
3371 }
3372 }
3373 }
3374 // Recheck with a better notion of 'required_outcnt'
3375 if (n->outcnt() != required_outcnt) {
3376 record_method_not_compilable("malformed control flow");
3377 return true; // Not all targets reachable!
3378 }
3379 }
3380 // Check that I actually visited all kids. Unreached kids
3381 // must be infinite loops.
3382 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
3383 if (!frc._visited.test(n->fast_out(j)->_idx)) {
3384 record_method_not_compilable("infinite loop");
3385 return true; // Found unvisited kid; must be unreach
3386 }
3387 }
3388
3389 // If original bytecodes contained a mixture of floats and doubles
3390 // check if the optimizer has made it homogenous, item (3).
3391 if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
3392 frc.get_float_count() > 32 &&
3393 frc.get_double_count() == 0 &&
3394 (10 * frc.get_call_count() < frc.get_float_count()) ) {
3395 set_24_bit_selection_and_mode( false, true );
3396 }
3397
3398 set_java_calls(frc.get_java_call_count());
3399 set_inner_loops(frc.get_inner_loop_count());
3400
3401 // No infinite loops, no reason to bail out.
3402 return false;
3403 }
3404
3405 //-----------------------------too_many_traps----------------------------------
3406 // Report if there are too many traps at the current method and bci.
3407 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
3408 bool Compile::too_many_traps(ciMethod* method,
3409 int bci,
3410 Deoptimization::DeoptReason reason) {
3411 ciMethodData* md = method->method_data();
3412 if (md->is_empty()) {
3413 // Assume the trap has not occurred, or that it occurred only
3414 // because of a transient condition during start-up in the interpreter.
3415 return false;
3416 }
3417 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3418 if (md->has_trap_at(bci, m, reason) != 0) {
3419 // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
3420 // Also, if there are multiple reasons, or if there is no per-BCI record,
3421 // assume the worst.
3422 if (log())
3423 log()->elem("observe trap='%s' count='%d'",
3424 Deoptimization::trap_reason_name(reason),
3425 md->trap_count(reason));
3426 return true;
3427 } else {
3428 // Ignore method/bci and see if there have been too many globally.
3429 return too_many_traps(reason, md);
3430 }
3431 }
3432
3433 // Less-accurate variant which does not require a method and bci.
3434 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
3435 ciMethodData* logmd) {
3436 if (trap_count(reason) >= Deoptimization::per_method_trap_limit(reason)) {
3437 // Too many traps globally.
3438 // Note that we use cumulative trap_count, not just md->trap_count.
3439 if (log()) {
3440 int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
3441 log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
3442 Deoptimization::trap_reason_name(reason),
3443 mcount, trap_count(reason));
3444 }
3445 return true;
3446 } else {
3447 // The coast is clear.
3448 return false;
3449 }
3450 }
3451
3452 //--------------------------too_many_recompiles--------------------------------
3453 // Report if there are too many recompiles at the current method and bci.
3454 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
3455 // Is not eager to return true, since this will cause the compiler to use
3456 // Action_none for a trap point, to avoid too many recompilations.
3457 bool Compile::too_many_recompiles(ciMethod* method,
3458 int bci,
3459 Deoptimization::DeoptReason reason) {
3460 ciMethodData* md = method->method_data();
3461 if (md->is_empty()) {
3462 // Assume the trap has not occurred, or that it occurred only
3463 // because of a transient condition during start-up in the interpreter.
3464 return false;
3465 }
3466 // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
3467 uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
3468 uint m_cutoff = (uint) PerMethodRecompilationCutoff / 2 + 1; // not zero
3469 Deoptimization::DeoptReason per_bc_reason
3470 = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
3471 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3472 if ((per_bc_reason == Deoptimization::Reason_none
3473 || md->has_trap_at(bci, m, reason) != 0)
3474 // The trap frequency measure we care about is the recompile count:
3475 && md->trap_recompiled_at(bci, m)
3476 && md->overflow_recompile_count() >= bc_cutoff) {
3477 // Do not emit a trap here if it has already caused recompilations.
3478 // Also, if there are multiple reasons, or if there is no per-BCI record,
3479 // assume the worst.
3480 if (log())
3481 log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
3482 Deoptimization::trap_reason_name(reason),
3483 md->trap_count(reason),
3484 md->overflow_recompile_count());
3485 return true;
3486 } else if (trap_count(reason) != 0
3487 && decompile_count() >= m_cutoff) {
3488 // Too many recompiles globally, and we have seen this sort of trap.
3489 // Use cumulative decompile_count, not just md->decompile_count.
3490 if (log())
3491 log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
3492 Deoptimization::trap_reason_name(reason),
3493 md->trap_count(reason), trap_count(reason),
3494 md->decompile_count(), decompile_count());
3495 return true;
3496 } else {
3497 // The coast is clear.
3498 return false;
3499 }
3500 }
3501
3502 // Compute when not to trap. Used by matching trap based nodes and
3503 // NullCheck optimization.
3504 void Compile::set_allowed_deopt_reasons() {
3505 _allowed_reasons = 0;
3506 if (is_method_compilation()) {
3507 for (int rs = (int)Deoptimization::Reason_none+1; rs < Compile::trapHistLength; rs++) {
3508 assert(rs < BitsPerInt, "recode bit map");
3509 if (!too_many_traps((Deoptimization::DeoptReason) rs)) {
3510 _allowed_reasons |= nth_bit(rs);
3511 }
3512 }
3513 }
3514 }
3515
3516 #ifndef PRODUCT
3517 //------------------------------verify_graph_edges---------------------------
3518 // Walk the Graph and verify that there is a one-to-one correspondence
3519 // between Use-Def edges and Def-Use edges in the graph.
3520 void Compile::verify_graph_edges(bool no_dead_code) {
3521 if (VerifyGraphEdges) {
3522 ResourceArea *area = Thread::current()->resource_area();
3523 Unique_Node_List visited(area);
3524 // Call recursive graph walk to check edges
3525 _root->verify_edges(visited);
3526 if (no_dead_code) {
3527 // Now make sure that no visited node is used by an unvisited node.
3528 bool dead_nodes = false;
3529 Unique_Node_List checked(area);
3530 while (visited.size() > 0) {
3531 Node* n = visited.pop();
3532 checked.push(n);
3533 for (uint i = 0; i < n->outcnt(); i++) {
3534 Node* use = n->raw_out(i);
3535 if (checked.member(use)) continue; // already checked
3536 if (visited.member(use)) continue; // already in the graph
3537 if (use->is_Con()) continue; // a dead ConNode is OK
3538 // At this point, we have found a dead node which is DU-reachable.
3539 if (!dead_nodes) {
3540 tty->print_cr("*** Dead nodes reachable via DU edges:");
3541 dead_nodes = true;
3542 }
3543 use->dump(2);
3544 tty->print_cr("---");
3545 checked.push(use); // No repeats; pretend it is now checked.
3546 }
3547 }
3548 assert(!dead_nodes, "using nodes must be reachable from root");
3549 }
3550 }
3551 }
3552
3553 // Verify GC barriers consistency
3554 // Currently supported:
3555 // - G1 pre-barriers (see GraphKit::g1_write_barrier_pre())
3556 void Compile::verify_barriers() {
3557 if (UseG1GC) {
3558 // Verify G1 pre-barriers
3559 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + PtrQueue::byte_offset_of_active());
3560
3561 ResourceArea *area = Thread::current()->resource_area();
3562 Unique_Node_List visited(area);
3563 Node_List worklist(area);
3564 // We're going to walk control flow backwards starting from the Root
3565 worklist.push(_root);
3566 while (worklist.size() > 0) {
3567 Node* x = worklist.pop();
3568 if (x == NULL || x == top()) continue;
3569 if (visited.member(x)) {
3570 continue;
3571 } else {
3572 visited.push(x);
3573 }
3574
3575 if (x->is_Region()) {
3576 for (uint i = 1; i < x->req(); i++) {
3577 worklist.push(x->in(i));
3578 }
3579 } else {
3580 worklist.push(x->in(0));
3581 // We are looking for the pattern:
3582 // /->ThreadLocal
3583 // If->Bool->CmpI->LoadB->AddP->ConL(marking_offset)
3584 // \->ConI(0)
3585 // We want to verify that the If and the LoadB have the same control
3586 // See GraphKit::g1_write_barrier_pre()
3587 if (x->is_If()) {
3588 IfNode *iff = x->as_If();
3589 if (iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) {
3590 CmpNode *cmp = iff->in(1)->in(1)->as_Cmp();
3591 if (cmp->Opcode() == Op_CmpI && cmp->in(2)->is_Con() && cmp->in(2)->bottom_type()->is_int()->get_con() == 0
3592 && cmp->in(1)->is_Load()) {
3593 LoadNode* load = cmp->in(1)->as_Load();
3594 if (load->Opcode() == Op_LoadB && load->in(2)->is_AddP() && load->in(2)->in(2)->Opcode() == Op_ThreadLocal
3595 && load->in(2)->in(3)->is_Con()
3596 && load->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == marking_offset) {
3597
3598 Node* if_ctrl = iff->in(0);
3599 Node* load_ctrl = load->in(0);
3600
3601 if (if_ctrl != load_ctrl) {
3602 // Skip possible CProj->NeverBranch in infinite loops
3603 if ((if_ctrl->is_Proj() && if_ctrl->Opcode() == Op_CProj)
3604 && (if_ctrl->in(0)->is_MultiBranch() && if_ctrl->in(0)->Opcode() == Op_NeverBranch)) {
3605 if_ctrl = if_ctrl->in(0)->in(0);
3606 }
3607 }
3608 assert(load_ctrl != NULL && if_ctrl == load_ctrl, "controls must match");
3609 }
3610 }
3611 }
3612 }
3613 }
3614 }
3615 }
3616 }
3617
3618 #endif
3619
3620 // The Compile object keeps track of failure reasons separately from the ciEnv.
3621 // This is required because there is not quite a 1-1 relation between the
3622 // ciEnv and its compilation task and the Compile object. Note that one
3623 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
3624 // to backtrack and retry without subsuming loads. Other than this backtracking
3625 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
3626 // by the logic in C2Compiler.
3627 void Compile::record_failure(const char* reason) {
3628 if (log() != NULL) {
3629 log()->elem("failure reason='%s' phase='compile'", reason);
3630 }
3631 if (_failure_reason == NULL) {
3632 // Record the first failure reason.
3633 _failure_reason = reason;
3634 }
3635
3636 if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
3637 C->print_method(PHASE_FAILURE);
3638 }
3639 _root = NULL; // flush the graph, too
3640 }
3641
3642 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator, bool dolog)
3643 : TraceTime(NULL, accumulator, false NOT_PRODUCT( || TimeCompiler ), false),
3644 _phase_name(name), _dolog(dolog)
3645 {
3646 if (dolog) {
3647 C = Compile::current();
3648 _log = C->log();
3649 } else {
3650 C = NULL;
3651 _log = NULL;
3652 }
3653 if (_log != NULL) {
3654 _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3655 _log->stamp();
3656 _log->end_head();
3657 }
3658 }
3659
3660 Compile::TracePhase::~TracePhase() {
3661
3662 C = Compile::current();
3663 if (_dolog) {
3664 _log = C->log();
3665 } else {
3666 _log = NULL;
3667 }
3668
3669 #ifdef ASSERT
3670 if (PrintIdealNodeCount) {
3671 tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
3672 _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
3673 }
3674
3675 if (VerifyIdealNodeCount) {
3676 Compile::current()->print_missing_nodes();
3677 }
3678 #endif
3679
3680 if (_log != NULL) {
3681 _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3682 }
3683 }
3684
3685 //=============================================================================
3686 // Two Constant's are equal when the type and the value are equal.
3687 bool Compile::Constant::operator==(const Constant& other) {
3688 if (type() != other.type() ) return false;
3689 if (can_be_reused() != other.can_be_reused()) return false;
3690 // For floating point values we compare the bit pattern.
3691 switch (type()) {
3692 case T_FLOAT: return (_v._value.i == other._v._value.i);
3693 case T_LONG:
3694 case T_DOUBLE: return (_v._value.j == other._v._value.j);
3695 case T_OBJECT:
3696 case T_ADDRESS: return (_v._value.l == other._v._value.l);
3697 case T_VOID: return (_v._value.l == other._v._value.l); // jump-table entries
3698 case T_METADATA: return (_v._metadata == other._v._metadata);
3699 default: ShouldNotReachHere();
3700 }
3701 return false;
3702 }
3703
3704 static int type_to_size_in_bytes(BasicType t) {
3705 switch (t) {
3706 case T_LONG: return sizeof(jlong );
3707 case T_FLOAT: return sizeof(jfloat );
3708 case T_DOUBLE: return sizeof(jdouble);
3709 case T_METADATA: return sizeof(Metadata*);
3710 // We use T_VOID as marker for jump-table entries (labels) which
3711 // need an internal word relocation.
3712 case T_VOID:
3713 case T_ADDRESS:
3714 case T_OBJECT: return sizeof(jobject);
3715 }
3716
3717 ShouldNotReachHere();
3718 return -1;
3719 }
3720
3721 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
3722 // sort descending
3723 if (a->freq() > b->freq()) return -1;
3724 if (a->freq() < b->freq()) return 1;
3725 return 0;
3726 }
3727
3728 void Compile::ConstantTable::calculate_offsets_and_size() {
3729 // First, sort the array by frequencies.
3730 _constants.sort(qsort_comparator);
3731
3732 #ifdef ASSERT
3733 // Make sure all jump-table entries were sorted to the end of the
3734 // array (they have a negative frequency).
3735 bool found_void = false;
3736 for (int i = 0; i < _constants.length(); i++) {
3737 Constant con = _constants.at(i);
3738 if (con.type() == T_VOID)
3739 found_void = true; // jump-tables
3740 else
3741 assert(!found_void, "wrong sorting");
3742 }
3743 #endif
3744
3745 int offset = 0;
3746 for (int i = 0; i < _constants.length(); i++) {
3747 Constant* con = _constants.adr_at(i);
3748
3749 // Align offset for type.
3750 int typesize = type_to_size_in_bytes(con->type());
3751 offset = align_size_up(offset, typesize);
3752 con->set_offset(offset); // set constant's offset
3753
3754 if (con->type() == T_VOID) {
3755 MachConstantNode* n = (MachConstantNode*) con->get_jobject();
3756 offset = offset + typesize * n->outcnt(); // expand jump-table
3757 } else {
3758 offset = offset + typesize;
3759 }
3760 }
3761
3762 // Align size up to the next section start (which is insts; see
3763 // CodeBuffer::align_at_start).
3764 assert(_size == -1, "already set?");
3765 _size = align_size_up(offset, CodeEntryAlignment);
3766 }
3767
3768 void Compile::ConstantTable::emit(CodeBuffer& cb) {
3769 MacroAssembler _masm(&cb);
3770 for (int i = 0; i < _constants.length(); i++) {
3771 Constant con = _constants.at(i);
3772 address constant_addr = NULL;
3773 switch (con.type()) {
3774 case T_LONG: constant_addr = _masm.long_constant( con.get_jlong() ); break;
3775 case T_FLOAT: constant_addr = _masm.float_constant( con.get_jfloat() ); break;
3776 case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
3777 case T_OBJECT: {
3778 jobject obj = con.get_jobject();
3779 int oop_index = _masm.oop_recorder()->find_index(obj);
3780 constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
3781 break;
3782 }
3783 case T_ADDRESS: {
3784 address addr = (address) con.get_jobject();
3785 constant_addr = _masm.address_constant(addr);
3786 break;
3787 }
3788 // We use T_VOID as marker for jump-table entries (labels) which
3789 // need an internal word relocation.
3790 case T_VOID: {
3791 MachConstantNode* n = (MachConstantNode*) con.get_jobject();
3792 // Fill the jump-table with a dummy word. The real value is
3793 // filled in later in fill_jump_table.
3794 address dummy = (address) n;
3795 constant_addr = _masm.address_constant(dummy);
3796 // Expand jump-table
3797 for (uint i = 1; i < n->outcnt(); i++) {
3798 address temp_addr = _masm.address_constant(dummy + i);
3799 assert(temp_addr, "consts section too small");
3800 }
3801 break;
3802 }
3803 case T_METADATA: {
3804 Metadata* obj = con.get_metadata();
3805 int metadata_index = _masm.oop_recorder()->find_index(obj);
3806 constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
3807 break;
3808 }
3809 default: ShouldNotReachHere();
3810 }
3811 assert(constant_addr, "consts section too small");
3812 assert((constant_addr - _masm.code()->consts()->start()) == con.offset(),
3813 err_msg_res("must be: %d == %d", (int) (constant_addr - _masm.code()->consts()->start()), (int)(con.offset())));
3814 }
3815 }
3816
3817 int Compile::ConstantTable::find_offset(Constant& con) const {
3818 int idx = _constants.find(con);
3819 assert(idx != -1, "constant must be in constant table");
3820 int offset = _constants.at(idx).offset();
3821 assert(offset != -1, "constant table not emitted yet?");
3822 return offset;
3823 }
3824
3825 void Compile::ConstantTable::add(Constant& con) {
3826 if (con.can_be_reused()) {
3827 int idx = _constants.find(con);
3828 if (idx != -1 && _constants.at(idx).can_be_reused()) {
3829 _constants.adr_at(idx)->inc_freq(con.freq()); // increase the frequency by the current value
3830 return;
3831 }
3832 }
3833 (void) _constants.append(con);
3834 }
3835
3836 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
3837 Block* b = Compile::current()->cfg()->get_block_for_node(n);
3838 Constant con(type, value, b->_freq);
3839 add(con);
3840 return con;
3841 }
3842
3843 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
3844 Constant con(metadata);
3845 add(con);
3846 return con;
3847 }
3848
3849 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
3850 jvalue value;
3851 BasicType type = oper->type()->basic_type();
3852 switch (type) {
3853 case T_LONG: value.j = oper->constantL(); break;
3854 case T_FLOAT: value.f = oper->constantF(); break;
3855 case T_DOUBLE: value.d = oper->constantD(); break;
3856 case T_OBJECT:
3857 case T_ADDRESS: value.l = (jobject) oper->constant(); break;
3858 case T_METADATA: return add((Metadata*)oper->constant()); break;
3859 default: guarantee(false, err_msg_res("unhandled type: %s", type2name(type)));
3860 }
3861 return add(n, type, value);
3862 }
3863
3864 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
3865 jvalue value;
3866 // We can use the node pointer here to identify the right jump-table
3867 // as this method is called from Compile::Fill_buffer right before
3868 // the MachNodes are emitted and the jump-table is filled (means the
3869 // MachNode pointers do not change anymore).
3870 value.l = (jobject) n;
3871 Constant con(T_VOID, value, next_jump_table_freq(), false); // Labels of a jump-table cannot be reused.
3872 add(con);
3873 return con;
3874 }
3875
3876 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
3877 // If called from Compile::scratch_emit_size do nothing.
3878 if (Compile::current()->in_scratch_emit_size()) return;
3879
3880 assert(labels.is_nonempty(), "must be");
3881 assert((uint) labels.length() == n->outcnt(), err_msg_res("must be equal: %d == %d", labels.length(), n->outcnt()));
3882
3883 // Since MachConstantNode::constant_offset() also contains
3884 // table_base_offset() we need to subtract the table_base_offset()
3885 // to get the plain offset into the constant table.
3886 int offset = n->constant_offset() - table_base_offset();
3887
3888 MacroAssembler _masm(&cb);
3889 address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
3890
3891 for (uint i = 0; i < n->outcnt(); i++) {
3892 address* constant_addr = &jump_table_base[i];
3893 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)));
3894 *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
3895 cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
3896 }
3897 }
3898
3899 void Compile::dump_inlining() {
3900 if (print_inlining() || print_intrinsics()) {
3901 // Print inlining message for candidates that we couldn't inline
3902 // for lack of space or non constant receiver
3903 for (int i = 0; i < _late_inlines.length(); i++) {
3904 CallGenerator* cg = _late_inlines.at(i);
3905 cg->print_inlining_late("live nodes > LiveNodeCountInliningCutoff");
3906 }
3907 Unique_Node_List useful;
3908 useful.push(root());
3909 for (uint next = 0; next < useful.size(); ++next) {
3910 Node* n = useful.at(next);
3911 if (n->is_Call() && n->as_Call()->generator() != NULL && n->as_Call()->generator()->call_node() == n) {
3912 CallNode* call = n->as_Call();
3913 CallGenerator* cg = call->generator();
3914 cg->print_inlining_late("receiver not constant");
3915 }
3916 uint max = n->len();
3917 for ( uint i = 0; i < max; ++i ) {
3918 Node *m = n->in(i);
3919 if ( m == NULL ) continue;
3920 useful.push(m);
3921 }
3922 }
3923 for (int i = 0; i < _print_inlining_list->length(); i++) {
3924 tty->print("%s", _print_inlining_list->adr_at(i)->ss()->as_string());
3925 }
3926 }
3927 }
3928
3929 // Dump inlining replay data to the stream.
3930 // Don't change thread state and acquire any locks.
3931 void Compile::dump_inline_data(outputStream* out) {
3932 InlineTree* inl_tree = ilt();
3933 if (inl_tree != NULL) {
3934 out->print(" inline %d", inl_tree->count());
3935 inl_tree->dump_replay_data(out);
3936 }
3937 }
3938
3939 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
3940 if (n1->Opcode() < n2->Opcode()) return -1;
3941 else if (n1->Opcode() > n2->Opcode()) return 1;
3942
3943 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()));
3944 for (uint i = 1; i < n1->req(); i++) {
3945 if (n1->in(i) < n2->in(i)) return -1;
3946 else if (n1->in(i) > n2->in(i)) return 1;
3947 }
3948
3949 return 0;
3950 }
3951
3952 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
3953 Node* n1 = *n1p;
3954 Node* n2 = *n2p;
3955
3956 return cmp_expensive_nodes(n1, n2);
3957 }
3958
3959 void Compile::sort_expensive_nodes() {
3960 if (!expensive_nodes_sorted()) {
3961 _expensive_nodes->sort(cmp_expensive_nodes);
3962 }
3963 }
3964
3965 bool Compile::expensive_nodes_sorted() const {
3966 for (int i = 1; i < _expensive_nodes->length(); i++) {
3967 if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
3968 return false;
3969 }
3970 }
3971 return true;
3972 }
3973
3974 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
3975 if (_expensive_nodes->length() == 0) {
3976 return false;
3977 }
3978
3979 assert(OptimizeExpensiveOps, "optimization off?");
3980
3981 // Take this opportunity to remove dead nodes from the list
3982 int j = 0;
3983 for (int i = 0; i < _expensive_nodes->length(); i++) {
3984 Node* n = _expensive_nodes->at(i);
3985 if (!n->is_unreachable(igvn)) {
3986 assert(n->is_expensive(), "should be expensive");
3987 _expensive_nodes->at_put(j, n);
3988 j++;
3989 }
3990 }
3991 _expensive_nodes->trunc_to(j);
3992
3993 // Then sort the list so that similar nodes are next to each other
3994 // and check for at least two nodes of identical kind with same data
3995 // inputs.
3996 sort_expensive_nodes();
3997
3998 for (int i = 0; i < _expensive_nodes->length()-1; i++) {
3999 if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
4000 return true;
4001 }
4002 }
4003
4004 return false;
4005 }
4006
4007 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
4008 if (_expensive_nodes->length() == 0) {
4009 return;
4010 }
4011
4012 assert(OptimizeExpensiveOps, "optimization off?");
4013
4014 // Sort to bring similar nodes next to each other and clear the
4015 // control input of nodes for which there's only a single copy.
4016 sort_expensive_nodes();
4017
4018 int j = 0;
4019 int identical = 0;
4020 int i = 0;
4021 for (; i < _expensive_nodes->length()-1; i++) {
4022 assert(j <= i, "can't write beyond current index");
4023 if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
4024 identical++;
4025 _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4026 continue;
4027 }
4028 if (identical > 0) {
4029 _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4030 identical = 0;
4031 } else {
4032 Node* n = _expensive_nodes->at(i);
4033 igvn.hash_delete(n);
4034 n->set_req(0, NULL);
4035 igvn.hash_insert(n);
4036 }
4037 }
4038 if (identical > 0) {
4039 _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4040 } else if (_expensive_nodes->length() >= 1) {
4041 Node* n = _expensive_nodes->at(i);
4042 igvn.hash_delete(n);
4043 n->set_req(0, NULL);
4044 igvn.hash_insert(n);
4045 }
4046 _expensive_nodes->trunc_to(j);
4047 }
4048
4049 void Compile::add_expensive_node(Node * n) {
4050 assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
4051 assert(n->is_expensive(), "expensive nodes with non-null control here only");
4052 assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
4053 if (OptimizeExpensiveOps) {
4054 _expensive_nodes->append(n);
4055 } else {
4056 // Clear control input and let IGVN optimize expensive nodes if
4057 // OptimizeExpensiveOps is off.
4058 n->set_req(0, NULL);
4059 }
4060 }
4061
4062 /**
4063 * Remove the speculative part of types and clean up the graph
4064 */
4065 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
4066 if (UseTypeSpeculation) {
4067 Unique_Node_List worklist;
4068 worklist.push(root());
4069 int modified = 0;
4070 // Go over all type nodes that carry a speculative type, drop the
4071 // speculative part of the type and enqueue the node for an igvn
4072 // which may optimize it out.
4073 for (uint next = 0; next < worklist.size(); ++next) {
4074 Node *n = worklist.at(next);
4075 if (n->is_Type()) {
4076 TypeNode* tn = n->as_Type();
4077 const Type* t = tn->type();
4078 const Type* t_no_spec = t->remove_speculative();
4079 if (t_no_spec != t) {
4080 bool in_hash = igvn.hash_delete(n);
4081 assert(in_hash, "node should be in igvn hash table");
4082 tn->set_type(t_no_spec);
4083 igvn.hash_insert(n);
4084 igvn._worklist.push(n); // give it a chance to go away
4085 modified++;
4086 }
4087 }
4088 uint max = n->len();
4089 for( uint i = 0; i < max; ++i ) {
4090 Node *m = n->in(i);
4091 if (not_a_node(m)) continue;
4092 worklist.push(m);
4093 }
4094 }
4095 // Drop the speculative part of all types in the igvn's type table
4096 igvn.remove_speculative_types();
4097 if (modified > 0) {
4098 igvn.optimize();
4099 }
4100 #ifdef ASSERT
4101 // Verify that after the IGVN is over no speculative type has resurfaced
4102 worklist.clear();
4103 worklist.push(root());
4104 for (uint next = 0; next < worklist.size(); ++next) {
4105 Node *n = worklist.at(next);
4106 const Type* t = igvn.type_or_null(n);
4107 assert((t == NULL) || (t == t->remove_speculative()), "no more speculative types");
4108 if (n->is_Type()) {
4109 t = n->as_Type()->type();
4110 assert(t == t->remove_speculative(), "no more speculative types");
4111 }
4112 uint max = n->len();
4113 for( uint i = 0; i < max; ++i ) {
4114 Node *m = n->in(i);
4115 if (not_a_node(m)) continue;
4116 worklist.push(m);
4117 }
4118 }
4119 igvn.check_no_speculative_types();
4120 #endif
4121 }
4122 }
4123
4124 // Convert integer value to a narrowed long type dependent on ctrl (for example, a range check)
4125 Node* Compile::constrained_convI2L(PhaseGVN* phase, Node* value, const TypeInt* itype, Node* ctrl) {
4126 if (ctrl != NULL) {
4127 // Express control dependency by a CastII node with a narrow type.
4128 value = new (phase->C) CastIINode(value, itype, false, true /* range check dependency */);
4129 // Make the CastII node dependent on the control input to prevent the narrowed ConvI2L
4130 // node from floating above the range check during loop optimizations. Otherwise, the
4131 // ConvI2L node may be eliminated independently of the range check, causing the data path
4132 // to become TOP while the control path is still there (although it's unreachable).
4133 value->set_req(0, ctrl);
4134 // Save CastII node to remove it after loop optimizations.
4135 phase->C->add_range_check_cast(value);
4136 value = phase->transform(value);
4137 }
4138 const TypeLong* ltype = TypeLong::make(itype->_lo, itype->_hi, itype->_widen);
4139 return phase->transform(new (phase->C) ConvI2LNode(value, ltype));
4140 }
4141
4142 // Auxiliary method to support randomized stressing/fuzzing.
4143 //
4144 // This method can be called the arbitrary number of times, with current count
4145 // as the argument. The logic allows selecting a single candidate from the
4146 // running list of candidates as follows:
4147 // int count = 0;
4148 // Cand* selected = null;
4149 // while(cand = cand->next()) {
4150 // if (randomized_select(++count)) {
4151 // selected = cand;
4152 // }
4153 // }
4154 //
4155 // Including count equalizes the chances any candidate is "selected".
4156 // This is useful when we don't have the complete list of candidates to choose
4157 // from uniformly. In this case, we need to adjust the randomicity of the
4158 // selection, or else we will end up biasing the selection towards the latter
4159 // candidates.
4160 //
4161 // Quick back-envelope calculation shows that for the list of n candidates
4162 // the equal probability for the candidate to persist as "best" can be
4163 // achieved by replacing it with "next" k-th candidate with the probability
4164 // of 1/k. It can be easily shown that by the end of the run, the
4165 // probability for any candidate is converged to 1/n, thus giving the
4166 // uniform distribution among all the candidates.
4167 //
4168 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
4169 #define RANDOMIZED_DOMAIN_POW 29
4170 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
4171 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
4172 bool Compile::randomized_select(int count) {
4173 assert(count > 0, "only positive");
4174 return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);
4175 }