1 /*
2 * Copyright (c) 1997, 2011, 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/assembler.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "code/exceptionHandlerTable.hpp"
29 #include "code/nmethod.hpp"
30 #include "compiler/compileLog.hpp"
31 #include "compiler/oopMap.hpp"
32 #include "opto/addnode.hpp"
33 #include "opto/block.hpp"
34 #include "opto/c2compiler.hpp"
35 #include "opto/callGenerator.hpp"
36 #include "opto/callnode.hpp"
37 #include "opto/cfgnode.hpp"
38 #include "opto/chaitin.hpp"
39 #include "opto/compile.hpp"
40 #include "opto/connode.hpp"
41 #include "opto/divnode.hpp"
42 #include "opto/escape.hpp"
43 #include "opto/idealGraphPrinter.hpp"
44 #include "opto/loopnode.hpp"
45 #include "opto/machnode.hpp"
46 #include "opto/macro.hpp"
47 #include "opto/matcher.hpp"
48 #include "opto/memnode.hpp"
49 #include "opto/mulnode.hpp"
50 #include "opto/node.hpp"
51 #include "opto/opcodes.hpp"
52 #include "opto/output.hpp"
53 #include "opto/parse.hpp"
54 #include "opto/phaseX.hpp"
55 #include "opto/rootnode.hpp"
56 #include "opto/runtime.hpp"
57 #include "opto/stringopts.hpp"
58 #include "opto/type.hpp"
59 #include "opto/vectornode.hpp"
60 #include "runtime/arguments.hpp"
61 #include "runtime/signature.hpp"
62 #include "runtime/stubRoutines.hpp"
63 #include "runtime/timer.hpp"
64 #include "utilities/copy.hpp"
65 #ifdef TARGET_ARCH_MODEL_x86_32
66 # include "adfiles/ad_x86_32.hpp"
67 #endif
68 #ifdef TARGET_ARCH_MODEL_x86_64
69 # include "adfiles/ad_x86_64.hpp"
70 #endif
71 #ifdef TARGET_ARCH_MODEL_sparc
72 # include "adfiles/ad_sparc.hpp"
73 #endif
74 #ifdef TARGET_ARCH_MODEL_zero
75 # include "adfiles/ad_zero.hpp"
76 #endif
77 #ifdef TARGET_ARCH_MODEL_arm
78 # include "adfiles/ad_arm.hpp"
79 #endif
80 #ifdef TARGET_ARCH_MODEL_ppc
81 # include "adfiles/ad_ppc.hpp"
82 #endif
83
84
85 // -------------------- Compile::mach_constant_base_node -----------------------
86 // Constant table base node singleton.
87 MachConstantBaseNode* Compile::mach_constant_base_node() {
88 if (_mach_constant_base_node == NULL) {
89 _mach_constant_base_node = new (C) MachConstantBaseNode();
90 _mach_constant_base_node->add_req(C->root());
91 }
92 return _mach_constant_base_node;
93 }
94
95
96 /// Support for intrinsics.
97
98 // Return the index at which m must be inserted (or already exists).
99 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
100 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual) {
101 #ifdef ASSERT
102 for (int i = 1; i < _intrinsics->length(); i++) {
103 CallGenerator* cg1 = _intrinsics->at(i-1);
104 CallGenerator* cg2 = _intrinsics->at(i);
105 assert(cg1->method() != cg2->method()
106 ? cg1->method() < cg2->method()
107 : cg1->is_virtual() < cg2->is_virtual(),
108 "compiler intrinsics list must stay sorted");
109 }
110 #endif
111 // Binary search sorted list, in decreasing intervals [lo, hi].
112 int lo = 0, hi = _intrinsics->length()-1;
113 while (lo <= hi) {
114 int mid = (uint)(hi + lo) / 2;
115 ciMethod* mid_m = _intrinsics->at(mid)->method();
116 if (m < mid_m) {
117 hi = mid-1;
118 } else if (m > mid_m) {
119 lo = mid+1;
120 } else {
121 // look at minor sort key
122 bool mid_virt = _intrinsics->at(mid)->is_virtual();
123 if (is_virtual < mid_virt) {
124 hi = mid-1;
125 } else if (is_virtual > mid_virt) {
126 lo = mid+1;
127 } else {
128 return mid; // exact match
129 }
130 }
131 }
132 return lo; // inexact match
133 }
134
135 void Compile::register_intrinsic(CallGenerator* cg) {
136 if (_intrinsics == NULL) {
137 _intrinsics = new GrowableArray<CallGenerator*>(60);
138 }
139 // This code is stolen from ciObjectFactory::insert.
140 // Really, GrowableArray should have methods for
141 // insert_at, remove_at, and binary_search.
142 int len = _intrinsics->length();
143 int index = intrinsic_insertion_index(cg->method(), cg->is_virtual());
144 if (index == len) {
145 _intrinsics->append(cg);
146 } else {
147 #ifdef ASSERT
148 CallGenerator* oldcg = _intrinsics->at(index);
149 assert(oldcg->method() != cg->method() || oldcg->is_virtual() != cg->is_virtual(), "don't register twice");
150 #endif
151 _intrinsics->append(_intrinsics->at(len-1));
152 int pos;
153 for (pos = len-2; pos >= index; pos--) {
154 _intrinsics->at_put(pos+1,_intrinsics->at(pos));
155 }
156 _intrinsics->at_put(index, cg);
157 }
158 assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
159 }
160
161 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
162 assert(m->is_loaded(), "don't try this on unloaded methods");
163 if (_intrinsics != NULL) {
164 int index = intrinsic_insertion_index(m, is_virtual);
165 if (index < _intrinsics->length()
166 && _intrinsics->at(index)->method() == m
167 && _intrinsics->at(index)->is_virtual() == is_virtual) {
168 return _intrinsics->at(index);
169 }
170 }
171 // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
172 if (m->intrinsic_id() != vmIntrinsics::_none &&
173 m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
174 CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
175 if (cg != NULL) {
176 // Save it for next time:
177 register_intrinsic(cg);
178 return cg;
179 } else {
180 gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
181 }
182 }
183 return NULL;
184 }
185
186 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
187 // in library_call.cpp.
188
189
190 #ifndef PRODUCT
191 // statistics gathering...
192
193 juint Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
194 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
195
196 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
197 assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
198 int oflags = _intrinsic_hist_flags[id];
199 assert(flags != 0, "what happened?");
200 if (is_virtual) {
201 flags |= _intrinsic_virtual;
202 }
203 bool changed = (flags != oflags);
204 if ((flags & _intrinsic_worked) != 0) {
205 juint count = (_intrinsic_hist_count[id] += 1);
206 if (count == 1) {
207 changed = true; // first time
208 }
209 // increment the overall count also:
210 _intrinsic_hist_count[vmIntrinsics::_none] += 1;
211 }
212 if (changed) {
213 if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
214 // Something changed about the intrinsic's virtuality.
215 if ((flags & _intrinsic_virtual) != 0) {
216 // This is the first use of this intrinsic as a virtual call.
217 if (oflags != 0) {
218 // We already saw it as a non-virtual, so note both cases.
219 flags |= _intrinsic_both;
220 }
221 } else if ((oflags & _intrinsic_both) == 0) {
222 // This is the first use of this intrinsic as a non-virtual
223 flags |= _intrinsic_both;
224 }
225 }
226 _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
227 }
228 // update the overall flags also:
229 _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
230 return changed;
231 }
232
233 static char* format_flags(int flags, char* buf) {
234 buf[0] = 0;
235 if ((flags & Compile::_intrinsic_worked) != 0) strcat(buf, ",worked");
236 if ((flags & Compile::_intrinsic_failed) != 0) strcat(buf, ",failed");
237 if ((flags & Compile::_intrinsic_disabled) != 0) strcat(buf, ",disabled");
238 if ((flags & Compile::_intrinsic_virtual) != 0) strcat(buf, ",virtual");
239 if ((flags & Compile::_intrinsic_both) != 0) strcat(buf, ",nonvirtual");
240 if (buf[0] == 0) strcat(buf, ",");
241 assert(buf[0] == ',', "must be");
242 return &buf[1];
243 }
244
245 void Compile::print_intrinsic_statistics() {
246 char flagsbuf[100];
247 ttyLocker ttyl;
248 if (xtty != NULL) xtty->head("statistics type='intrinsic'");
249 tty->print_cr("Compiler intrinsic usage:");
250 juint total = _intrinsic_hist_count[vmIntrinsics::_none];
251 if (total == 0) total = 1; // avoid div0 in case of no successes
252 #define PRINT_STAT_LINE(name, c, f) \
253 tty->print_cr(" %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
254 for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
255 vmIntrinsics::ID id = (vmIntrinsics::ID) index;
256 int flags = _intrinsic_hist_flags[id];
257 juint count = _intrinsic_hist_count[id];
258 if ((flags | count) != 0) {
259 PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
260 }
261 }
262 PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
263 if (xtty != NULL) xtty->tail("statistics");
264 }
265
266 void Compile::print_statistics() {
267 { ttyLocker ttyl;
268 if (xtty != NULL) xtty->head("statistics type='opto'");
269 Parse::print_statistics();
270 PhaseCCP::print_statistics();
271 PhaseRegAlloc::print_statistics();
272 Scheduling::print_statistics();
273 PhasePeephole::print_statistics();
274 PhaseIdealLoop::print_statistics();
275 if (xtty != NULL) xtty->tail("statistics");
276 }
277 if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
278 // put this under its own <statistics> element.
279 print_intrinsic_statistics();
280 }
281 }
282 #endif //PRODUCT
283
284 // Support for bundling info
285 Bundle* Compile::node_bundling(const Node *n) {
286 assert(valid_bundle_info(n), "oob");
287 return &_node_bundling_base[n->_idx];
288 }
289
290 bool Compile::valid_bundle_info(const Node *n) {
291 return (_node_bundling_limit > n->_idx);
292 }
293
294
295 void Compile::gvn_replace_by(Node* n, Node* nn) {
296 for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
297 Node* use = n->last_out(i);
298 bool is_in_table = initial_gvn()->hash_delete(use);
299 uint uses_found = 0;
300 for (uint j = 0; j < use->len(); j++) {
301 if (use->in(j) == n) {
302 if (j < use->req())
303 use->set_req(j, nn);
304 else
305 use->set_prec(j, nn);
306 uses_found++;
307 }
308 }
309 if (is_in_table) {
310 // reinsert into table
311 initial_gvn()->hash_find_insert(use);
312 }
313 record_for_igvn(use);
314 i -= uses_found; // we deleted 1 or more copies of this edge
315 }
316 }
317
318
319
320
321 // Identify all nodes that are reachable from below, useful.
322 // Use breadth-first pass that records state in a Unique_Node_List,
323 // recursive traversal is slower.
324 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
325 int estimated_worklist_size = unique();
326 useful.map( estimated_worklist_size, NULL ); // preallocate space
327
328 // Initialize worklist
329 if (root() != NULL) { useful.push(root()); }
330 // If 'top' is cached, declare it useful to preserve cached node
331 if( cached_top_node() ) { useful.push(cached_top_node()); }
332
333 // Push all useful nodes onto the list, breadthfirst
334 for( uint next = 0; next < useful.size(); ++next ) {
335 assert( next < unique(), "Unique useful nodes < total nodes");
336 Node *n = useful.at(next);
337 uint max = n->len();
338 for( uint i = 0; i < max; ++i ) {
339 Node *m = n->in(i);
340 if( m == NULL ) continue;
341 useful.push(m);
342 }
343 }
344 }
345
346 // Disconnect all useless nodes by disconnecting those at the boundary.
347 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
348 uint next = 0;
349 while( next < useful.size() ) {
350 Node *n = useful.at(next++);
351 // Use raw traversal of out edges since this code removes out edges
352 int max = n->outcnt();
353 for (int j = 0; j < max; ++j ) {
354 Node* child = n->raw_out(j);
355 if( ! useful.member(child) ) {
356 assert( !child->is_top() || child != top(),
357 "If top is cached in Compile object it is in useful list");
358 // Only need to remove this out-edge to the useless node
359 n->raw_del_out(j);
360 --j;
361 --max;
362 }
363 }
364 if (n->outcnt() == 1 && n->has_special_unique_user()) {
365 record_for_igvn( n->unique_out() );
366 }
367 }
368 debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
369 }
370
371 //------------------------------frame_size_in_words-----------------------------
372 // frame_slots in units of words
373 int Compile::frame_size_in_words() const {
374 // shift is 0 in LP32 and 1 in LP64
375 const int shift = (LogBytesPerWord - LogBytesPerInt);
376 int words = _frame_slots >> shift;
377 assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
378 return words;
379 }
380
381 // ============================================================================
382 //------------------------------CompileWrapper---------------------------------
383 class CompileWrapper : public StackObj {
384 Compile *const _compile;
385 public:
386 CompileWrapper(Compile* compile);
387
388 ~CompileWrapper();
389 };
390
391 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
392 // the Compile* pointer is stored in the current ciEnv:
393 ciEnv* env = compile->env();
394 assert(env == ciEnv::current(), "must already be a ciEnv active");
395 assert(env->compiler_data() == NULL, "compile already active?");
396 env->set_compiler_data(compile);
397 assert(compile == Compile::current(), "sanity");
398
399 compile->set_type_dict(NULL);
400 compile->set_type_hwm(NULL);
401 compile->set_type_last_size(0);
402 compile->set_last_tf(NULL, NULL);
403 compile->set_indexSet_arena(NULL);
404 compile->set_indexSet_free_block_list(NULL);
405 compile->init_type_arena();
406 Type::Initialize(compile);
407 _compile->set_scratch_buffer_blob(NULL);
408 _compile->begin_method();
409 }
410 CompileWrapper::~CompileWrapper() {
411 _compile->end_method();
412 if (_compile->scratch_buffer_blob() != NULL)
413 BufferBlob::free(_compile->scratch_buffer_blob());
414 _compile->env()->set_compiler_data(NULL);
415 }
416
417
418 //----------------------------print_compile_messages---------------------------
419 void Compile::print_compile_messages() {
420 #ifndef PRODUCT
421 // Check if recompiling
422 if (_subsume_loads == false && PrintOpto) {
423 // Recompiling without allowing machine instructions to subsume loads
424 tty->print_cr("*********************************************************");
425 tty->print_cr("** Bailout: Recompile without subsuming loads **");
426 tty->print_cr("*********************************************************");
427 }
428 if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
429 // Recompiling without escape analysis
430 tty->print_cr("*********************************************************");
431 tty->print_cr("** Bailout: Recompile without escape analysis **");
432 tty->print_cr("*********************************************************");
433 }
434 if (env()->break_at_compile()) {
435 // Open the debugger when compiling this method.
436 tty->print("### Breaking when compiling: ");
437 method()->print_short_name();
438 tty->cr();
439 BREAKPOINT;
440 }
441
442 if( PrintOpto ) {
443 if (is_osr_compilation()) {
444 tty->print("[OSR]%3d", _compile_id);
445 } else {
446 tty->print("%3d", _compile_id);
447 }
448 }
449 #endif
450 }
451
452
453 //-----------------------init_scratch_buffer_blob------------------------------
454 // Construct a temporary BufferBlob and cache it for this compile.
455 void Compile::init_scratch_buffer_blob(int const_size) {
456 // If there is already a scratch buffer blob allocated and the
457 // constant section is big enough, use it. Otherwise free the
458 // current and allocate a new one.
459 BufferBlob* blob = scratch_buffer_blob();
460 if ((blob != NULL) && (const_size <= _scratch_const_size)) {
461 // Use the current blob.
462 } else {
463 if (blob != NULL) {
464 BufferBlob::free(blob);
465 }
466
467 ResourceMark rm;
468 _scratch_const_size = const_size;
469 int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
470 blob = BufferBlob::create("Compile::scratch_buffer", size);
471 // Record the buffer blob for next time.
472 set_scratch_buffer_blob(blob);
473 // Have we run out of code space?
474 if (scratch_buffer_blob() == NULL) {
475 // Let CompilerBroker disable further compilations.
476 record_failure("Not enough space for scratch buffer in CodeCache");
477 return;
478 }
479 }
480
481 // Initialize the relocation buffers
482 relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
483 set_scratch_locs_memory(locs_buf);
484 }
485
486
487 //-----------------------scratch_emit_size-------------------------------------
488 // Helper function that computes size by emitting code
489 uint Compile::scratch_emit_size(const Node* n) {
490 // Start scratch_emit_size section.
491 set_in_scratch_emit_size(true);
492
493 // Emit into a trash buffer and count bytes emitted.
494 // This is a pretty expensive way to compute a size,
495 // but it works well enough if seldom used.
496 // All common fixed-size instructions are given a size
497 // method by the AD file.
498 // Note that the scratch buffer blob and locs memory are
499 // allocated at the beginning of the compile task, and
500 // may be shared by several calls to scratch_emit_size.
501 // The allocation of the scratch buffer blob is particularly
502 // expensive, since it has to grab the code cache lock.
503 BufferBlob* blob = this->scratch_buffer_blob();
504 assert(blob != NULL, "Initialize BufferBlob at start");
505 assert(blob->size() > MAX_inst_size, "sanity");
506 relocInfo* locs_buf = scratch_locs_memory();
507 address blob_begin = blob->content_begin();
508 address blob_end = (address)locs_buf;
509 assert(blob->content_contains(blob_end), "sanity");
510 CodeBuffer buf(blob_begin, blob_end - blob_begin);
511 buf.initialize_consts_size(_scratch_const_size);
512 buf.initialize_stubs_size(MAX_stubs_size);
513 assert(locs_buf != NULL, "sanity");
514 int lsize = MAX_locs_size / 3;
515 buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
516 buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
517 buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
518
519 // Do the emission.
520
521 // Fake label for branch instructions.
522 Label fakeL;
523 if (n->is_Branch() && n->as_Mach()->ideal_Opcode() != Op_Jump) {
524 MacroAssembler masm(&buf);
525 masm.bind(fakeL);
526 n->as_Mach()->label_set(fakeL, 0);
527 }
528 n->emit(buf, this->regalloc());
529
530 // End scratch_emit_size section.
531 set_in_scratch_emit_size(false);
532
533 return buf.insts_size();
534 }
535
536
537 // ============================================================================
538 //------------------------------Compile standard-------------------------------
539 debug_only( int Compile::_debug_idx = 100000; )
540
541 // Compile a method. entry_bci is -1 for normal compilations and indicates
542 // the continuation bci for on stack replacement.
543
544
545 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci, bool subsume_loads, bool do_escape_analysis )
546 : Phase(Compiler),
547 _env(ci_env),
548 _log(ci_env->log()),
549 _compile_id(ci_env->compile_id()),
550 _save_argument_registers(false),
551 _stub_name(NULL),
552 _stub_function(NULL),
553 _stub_entry_point(NULL),
554 _method(target),
555 _entry_bci(osr_bci),
556 _initial_gvn(NULL),
557 _for_igvn(NULL),
558 _warm_calls(NULL),
559 _subsume_loads(subsume_loads),
560 _do_escape_analysis(do_escape_analysis),
561 _failure_reason(NULL),
562 _code_buffer("Compile::Fill_buffer"),
563 _orig_pc_slot(0),
564 _orig_pc_slot_offset_in_bytes(0),
565 _has_method_handle_invokes(false),
566 _mach_constant_base_node(NULL),
567 _node_bundling_limit(0),
568 _node_bundling_base(NULL),
569 _java_calls(0),
570 _inner_loops(0),
571 _scratch_const_size(-1),
572 _in_scratch_emit_size(false),
573 #ifndef PRODUCT
574 _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
575 _printer(IdealGraphPrinter::printer()),
576 #endif
577 _congraph(NULL) {
578 C = this;
579
580 CompileWrapper cw(this);
581 #ifndef PRODUCT
582 if (TimeCompiler2) {
583 tty->print(" ");
584 target->holder()->name()->print();
585 tty->print(".");
586 target->print_short_name();
587 tty->print(" ");
588 }
589 TraceTime t1("Total compilation time", &_t_totalCompilation, TimeCompiler, TimeCompiler2);
590 TraceTime t2(NULL, &_t_methodCompilation, TimeCompiler, false);
591 bool print_opto_assembly = PrintOptoAssembly || _method->has_option("PrintOptoAssembly");
592 if (!print_opto_assembly) {
593 bool print_assembly = (PrintAssembly || _method->should_print_assembly());
594 if (print_assembly && !Disassembler::can_decode()) {
595 tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
596 print_opto_assembly = true;
597 }
598 }
599 set_print_assembly(print_opto_assembly);
600 set_parsed_irreducible_loop(false);
601 #endif
602
603 if (ProfileTraps) {
604 // Make sure the method being compiled gets its own MDO,
605 // so we can at least track the decompile_count().
606 method()->ensure_method_data();
607 }
608
609 Init(::AliasLevel);
610
611
612 print_compile_messages();
613
614 if (UseOldInlining || PrintCompilation NOT_PRODUCT( || PrintOpto) )
615 _ilt = InlineTree::build_inline_tree_root();
616 else
617 _ilt = NULL;
618
619 // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
620 assert(num_alias_types() >= AliasIdxRaw, "");
621
622 #define MINIMUM_NODE_HASH 1023
623 // Node list that Iterative GVN will start with
624 Unique_Node_List for_igvn(comp_arena());
625 set_for_igvn(&for_igvn);
626
627 // GVN that will be run immediately on new nodes
628 uint estimated_size = method()->code_size()*4+64;
629 estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
630 PhaseGVN gvn(node_arena(), estimated_size);
631 set_initial_gvn(&gvn);
632
633 { // Scope for timing the parser
634 TracePhase t3("parse", &_t_parser, true);
635
636 // Put top into the hash table ASAP.
637 initial_gvn()->transform_no_reclaim(top());
638
639 // Set up tf(), start(), and find a CallGenerator.
640 CallGenerator* cg = NULL;
641 if (is_osr_compilation()) {
642 const TypeTuple *domain = StartOSRNode::osr_domain();
643 const TypeTuple *range = TypeTuple::make_range(method()->signature());
644 init_tf(TypeFunc::make(domain, range));
645 StartNode* s = new (this, 2) StartOSRNode(root(), domain);
646 initial_gvn()->set_type_bottom(s);
647 init_start(s);
648 cg = CallGenerator::for_osr(method(), entry_bci());
649 } else {
650 // Normal case.
651 init_tf(TypeFunc::make(method()));
652 StartNode* s = new (this, 2) StartNode(root(), tf()->domain());
653 initial_gvn()->set_type_bottom(s);
654 init_start(s);
655 if (method()->intrinsic_id() == vmIntrinsics::_Reference_get && UseG1GC) {
656 // With java.lang.ref.reference.get() we must go through the
657 // intrinsic when G1 is enabled - even when get() is the root
658 // method of the compile - so that, if necessary, the value in
659 // the referent field of the reference object gets recorded by
660 // the pre-barrier code.
661 // Specifically, if G1 is enabled, the value in the referent
662 // field is recorded by the G1 SATB pre barrier. This will
663 // result in the referent being marked live and the reference
664 // object removed from the list of discovered references during
665 // reference processing.
666 cg = find_intrinsic(method(), false);
667 }
668 if (cg == NULL) {
669 float past_uses = method()->interpreter_invocation_count();
670 float expected_uses = past_uses;
671 cg = CallGenerator::for_inline(method(), expected_uses);
672 }
673 }
674 if (failing()) return;
675 if (cg == NULL) {
676 record_method_not_compilable_all_tiers("cannot parse method");
677 return;
678 }
679 JVMState* jvms = build_start_state(start(), tf());
680 if ((jvms = cg->generate(jvms)) == NULL) {
681 record_method_not_compilable("method parse failed");
682 return;
683 }
684 GraphKit kit(jvms);
685
686 if (!kit.stopped()) {
687 // Accept return values, and transfer control we know not where.
688 // This is done by a special, unique ReturnNode bound to root.
689 return_values(kit.jvms());
690 }
691
692 if (kit.has_exceptions()) {
693 // Any exceptions that escape from this call must be rethrown
694 // to whatever caller is dynamically above us on the stack.
695 // This is done by a special, unique RethrowNode bound to root.
696 rethrow_exceptions(kit.transfer_exceptions_into_jvms());
697 }
698
699 if (!failing() && has_stringbuilder()) {
700 {
701 // remove useless nodes to make the usage analysis simpler
702 ResourceMark rm;
703 PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
704 }
705
706 {
707 ResourceMark rm;
708 print_method("Before StringOpts", 3);
709 PhaseStringOpts pso(initial_gvn(), &for_igvn);
710 print_method("After StringOpts", 3);
711 }
712
713 // now inline anything that we skipped the first time around
714 while (_late_inlines.length() > 0) {
715 CallGenerator* cg = _late_inlines.pop();
716 cg->do_late_inline();
717 }
718 }
719 assert(_late_inlines.length() == 0, "should have been processed");
720
721 print_method("Before RemoveUseless", 3);
722
723 // Remove clutter produced by parsing.
724 if (!failing()) {
725 ResourceMark rm;
726 PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
727 }
728 }
729
730 // Note: Large methods are capped off in do_one_bytecode().
731 if (failing()) return;
732
733 // After parsing, node notes are no longer automagic.
734 // They must be propagated by register_new_node_with_optimizer(),
735 // clone(), or the like.
736 set_default_node_notes(NULL);
737
738 for (;;) {
739 int successes = Inline_Warm();
740 if (failing()) return;
741 if (successes == 0) break;
742 }
743
744 // Drain the list.
745 Finish_Warm();
746 #ifndef PRODUCT
747 if (_printer) {
748 _printer->print_inlining(this);
749 }
750 #endif
751
752 if (failing()) return;
753 NOT_PRODUCT( verify_graph_edges(); )
754
755 // Now optimize
756 Optimize();
757 if (failing()) return;
758 NOT_PRODUCT( verify_graph_edges(); )
759
760 #ifndef PRODUCT
761 if (PrintIdeal) {
762 ttyLocker ttyl; // keep the following output all in one block
763 // This output goes directly to the tty, not the compiler log.
764 // To enable tools to match it up with the compilation activity,
765 // be sure to tag this tty output with the compile ID.
766 if (xtty != NULL) {
767 xtty->head("ideal compile_id='%d'%s", compile_id(),
768 is_osr_compilation() ? " compile_kind='osr'" :
769 "");
770 }
771 root()->dump(9999);
772 if (xtty != NULL) {
773 xtty->tail("ideal");
774 }
775 }
776 #endif
777
778 // Now that we know the size of all the monitors we can add a fixed slot
779 // for the original deopt pc.
780
781 _orig_pc_slot = fixed_slots();
782 int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
783 set_fixed_slots(next_slot);
784
785 // Now generate code
786 Code_Gen();
787 if (failing()) return;
788
789 // Check if we want to skip execution of all compiled code.
790 {
791 #ifndef PRODUCT
792 if (OptoNoExecute) {
793 record_method_not_compilable("+OptoNoExecute"); // Flag as failed
794 return;
795 }
796 TracePhase t2("install_code", &_t_registerMethod, TimeCompiler);
797 #endif
798
799 if (is_osr_compilation()) {
800 _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
801 _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
802 } else {
803 _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
804 _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
805 }
806
807 env()->register_method(_method, _entry_bci,
808 &_code_offsets,
809 _orig_pc_slot_offset_in_bytes,
810 code_buffer(),
811 frame_size_in_words(), _oop_map_set,
812 &_handler_table, &_inc_table,
813 compiler,
814 env()->comp_level(),
815 true, /*has_debug_info*/
816 has_unsafe_access()
817 );
818 }
819 }
820
821 //------------------------------Compile----------------------------------------
822 // Compile a runtime stub
823 Compile::Compile( ciEnv* ci_env,
824 TypeFunc_generator generator,
825 address stub_function,
826 const char *stub_name,
827 int is_fancy_jump,
828 bool pass_tls,
829 bool save_arg_registers,
830 bool return_pc )
831 : Phase(Compiler),
832 _env(ci_env),
833 _log(ci_env->log()),
834 _compile_id(-1),
835 _save_argument_registers(save_arg_registers),
836 _method(NULL),
837 _stub_name(stub_name),
838 _stub_function(stub_function),
839 _stub_entry_point(NULL),
840 _entry_bci(InvocationEntryBci),
841 _initial_gvn(NULL),
842 _for_igvn(NULL),
843 _warm_calls(NULL),
844 _orig_pc_slot(0),
845 _orig_pc_slot_offset_in_bytes(0),
846 _subsume_loads(true),
847 _do_escape_analysis(false),
848 _failure_reason(NULL),
849 _code_buffer("Compile::Fill_buffer"),
850 _has_method_handle_invokes(false),
851 _mach_constant_base_node(NULL),
852 _node_bundling_limit(0),
853 _node_bundling_base(NULL),
854 _java_calls(0),
855 _inner_loops(0),
856 #ifndef PRODUCT
857 _trace_opto_output(TraceOptoOutput),
858 _printer(NULL),
859 #endif
860 _congraph(NULL) {
861 C = this;
862
863 #ifndef PRODUCT
864 TraceTime t1(NULL, &_t_totalCompilation, TimeCompiler, false);
865 TraceTime t2(NULL, &_t_stubCompilation, TimeCompiler, false);
866 set_print_assembly(PrintFrameConverterAssembly);
867 set_parsed_irreducible_loop(false);
868 #endif
869 CompileWrapper cw(this);
870 Init(/*AliasLevel=*/ 0);
871 init_tf((*generator)());
872
873 {
874 // The following is a dummy for the sake of GraphKit::gen_stub
875 Unique_Node_List for_igvn(comp_arena());
876 set_for_igvn(&for_igvn); // not used, but some GraphKit guys push on this
877 PhaseGVN gvn(Thread::current()->resource_area(),255);
878 set_initial_gvn(&gvn); // not significant, but GraphKit guys use it pervasively
879 gvn.transform_no_reclaim(top());
880
881 GraphKit kit;
882 kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
883 }
884
885 NOT_PRODUCT( verify_graph_edges(); )
886 Code_Gen();
887 if (failing()) return;
888
889
890 // Entry point will be accessed using compile->stub_entry_point();
891 if (code_buffer() == NULL) {
892 Matcher::soft_match_failure();
893 } else {
894 if (PrintAssembly && (WizardMode || Verbose))
895 tty->print_cr("### Stub::%s", stub_name);
896
897 if (!failing()) {
898 assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
899
900 // Make the NMethod
901 // For now we mark the frame as never safe for profile stackwalking
902 RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
903 code_buffer(),
904 CodeOffsets::frame_never_safe,
905 // _code_offsets.value(CodeOffsets::Frame_Complete),
906 frame_size_in_words(),
907 _oop_map_set,
908 save_arg_registers);
909 assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
910
911 _stub_entry_point = rs->entry_point();
912 }
913 }
914 }
915
916 #ifndef PRODUCT
917 void print_opto_verbose_signature( const TypeFunc *j_sig, const char *stub_name ) {
918 if(PrintOpto && Verbose) {
919 tty->print("%s ", stub_name); j_sig->print_flattened(); tty->cr();
920 }
921 }
922 #endif
923
924 void Compile::print_codes() {
925 }
926
927 //------------------------------Init-------------------------------------------
928 // Prepare for a single compilation
929 void Compile::Init(int aliaslevel) {
930 _unique = 0;
931 _regalloc = NULL;
932
933 _tf = NULL; // filled in later
934 _top = NULL; // cached later
935 _matcher = NULL; // filled in later
936 _cfg = NULL; // filled in later
937
938 set_24_bit_selection_and_mode(Use24BitFP, false);
939
940 _node_note_array = NULL;
941 _default_node_notes = NULL;
942
943 _immutable_memory = NULL; // filled in at first inquiry
944
945 // Globally visible Nodes
946 // First set TOP to NULL to give safe behavior during creation of RootNode
947 set_cached_top_node(NULL);
948 set_root(new (this, 3) RootNode());
949 // Now that you have a Root to point to, create the real TOP
950 set_cached_top_node( new (this, 1) ConNode(Type::TOP) );
951 set_recent_alloc(NULL, NULL);
952
953 // Create Debug Information Recorder to record scopes, oopmaps, etc.
954 env()->set_oop_recorder(new OopRecorder(comp_arena()));
955 env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
956 env()->set_dependencies(new Dependencies(env()));
957
958 _fixed_slots = 0;
959 set_has_split_ifs(false);
960 set_has_loops(has_method() && method()->has_loops()); // first approximation
961 set_has_stringbuilder(false);
962 _trap_can_recompile = false; // no traps emitted yet
963 _major_progress = true; // start out assuming good things will happen
964 set_has_unsafe_access(false);
965 Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
966 set_decompile_count(0);
967
968 set_do_freq_based_layout(BlockLayoutByFrequency || method_has_option("BlockLayoutByFrequency"));
969 set_num_loop_opts(LoopOptsCount);
970 set_do_inlining(Inline);
971 set_max_inline_size(MaxInlineSize);
972 set_freq_inline_size(FreqInlineSize);
973 set_do_scheduling(OptoScheduling);
974 set_do_count_invocations(false);
975 set_do_method_data_update(false);
976
977 if (debug_info()->recording_non_safepoints()) {
978 set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
979 (comp_arena(), 8, 0, NULL));
980 set_default_node_notes(Node_Notes::make(this));
981 }
982
983 // // -- Initialize types before each compile --
984 // // Update cached type information
985 // if( _method && _method->constants() )
986 // Type::update_loaded_types(_method, _method->constants());
987
988 // Init alias_type map.
989 if (!_do_escape_analysis && aliaslevel == 3)
990 aliaslevel = 2; // No unique types without escape analysis
991 _AliasLevel = aliaslevel;
992 const int grow_ats = 16;
993 _max_alias_types = grow_ats;
994 _alias_types = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
995 AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType, grow_ats);
996 Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
997 {
998 for (int i = 0; i < grow_ats; i++) _alias_types[i] = &ats[i];
999 }
1000 // Initialize the first few types.
1001 _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
1002 _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1003 _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1004 _num_alias_types = AliasIdxRaw+1;
1005 // Zero out the alias type cache.
1006 Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1007 // A NULL adr_type hits in the cache right away. Preload the right answer.
1008 probe_alias_cache(NULL)->_index = AliasIdxTop;
1009
1010 _intrinsics = NULL;
1011 _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1012 _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8, 0, NULL);
1013 register_library_intrinsics();
1014 }
1015
1016 //---------------------------init_start----------------------------------------
1017 // Install the StartNode on this compile object.
1018 void Compile::init_start(StartNode* s) {
1019 if (failing())
1020 return; // already failing
1021 assert(s == start(), "");
1022 }
1023
1024 StartNode* Compile::start() const {
1025 assert(!failing(), "");
1026 for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1027 Node* start = root()->fast_out(i);
1028 if( start->is_Start() )
1029 return start->as_Start();
1030 }
1031 ShouldNotReachHere();
1032 return NULL;
1033 }
1034
1035 //-------------------------------immutable_memory-------------------------------------
1036 // Access immutable memory
1037 Node* Compile::immutable_memory() {
1038 if (_immutable_memory != NULL) {
1039 return _immutable_memory;
1040 }
1041 StartNode* s = start();
1042 for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1043 Node *p = s->fast_out(i);
1044 if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1045 _immutable_memory = p;
1046 return _immutable_memory;
1047 }
1048 }
1049 ShouldNotReachHere();
1050 return NULL;
1051 }
1052
1053 //----------------------set_cached_top_node------------------------------------
1054 // Install the cached top node, and make sure Node::is_top works correctly.
1055 void Compile::set_cached_top_node(Node* tn) {
1056 if (tn != NULL) verify_top(tn);
1057 Node* old_top = _top;
1058 _top = tn;
1059 // Calling Node::setup_is_top allows the nodes the chance to adjust
1060 // their _out arrays.
1061 if (_top != NULL) _top->setup_is_top();
1062 if (old_top != NULL) old_top->setup_is_top();
1063 assert(_top == NULL || top()->is_top(), "");
1064 }
1065
1066 #ifndef PRODUCT
1067 void Compile::verify_top(Node* tn) const {
1068 if (tn != NULL) {
1069 assert(tn->is_Con(), "top node must be a constant");
1070 assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1071 assert(tn->in(0) != NULL, "must have live top node");
1072 }
1073 }
1074 #endif
1075
1076
1077 ///-------------------Managing Per-Node Debug & Profile Info-------------------
1078
1079 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1080 guarantee(arr != NULL, "");
1081 int num_blocks = arr->length();
1082 if (grow_by < num_blocks) grow_by = num_blocks;
1083 int num_notes = grow_by * _node_notes_block_size;
1084 Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1085 Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1086 while (num_notes > 0) {
1087 arr->append(notes);
1088 notes += _node_notes_block_size;
1089 num_notes -= _node_notes_block_size;
1090 }
1091 assert(num_notes == 0, "exact multiple, please");
1092 }
1093
1094 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1095 if (source == NULL || dest == NULL) return false;
1096
1097 if (dest->is_Con())
1098 return false; // Do not push debug info onto constants.
1099
1100 #ifdef ASSERT
1101 // Leave a bread crumb trail pointing to the original node:
1102 if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
1103 dest->set_debug_orig(source);
1104 }
1105 #endif
1106
1107 if (node_note_array() == NULL)
1108 return false; // Not collecting any notes now.
1109
1110 // This is a copy onto a pre-existing node, which may already have notes.
1111 // If both nodes have notes, do not overwrite any pre-existing notes.
1112 Node_Notes* source_notes = node_notes_at(source->_idx);
1113 if (source_notes == NULL || source_notes->is_clear()) return false;
1114 Node_Notes* dest_notes = node_notes_at(dest->_idx);
1115 if (dest_notes == NULL || dest_notes->is_clear()) {
1116 return set_node_notes_at(dest->_idx, source_notes);
1117 }
1118
1119 Node_Notes merged_notes = (*source_notes);
1120 // The order of operations here ensures that dest notes will win...
1121 merged_notes.update_from(dest_notes);
1122 return set_node_notes_at(dest->_idx, &merged_notes);
1123 }
1124
1125
1126 //--------------------------allow_range_check_smearing-------------------------
1127 // Gating condition for coalescing similar range checks.
1128 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1129 // single covering check that is at least as strong as any of them.
1130 // If the optimization succeeds, the simplified (strengthened) range check
1131 // will always succeed. If it fails, we will deopt, and then give up
1132 // on the optimization.
1133 bool Compile::allow_range_check_smearing() const {
1134 // If this method has already thrown a range-check,
1135 // assume it was because we already tried range smearing
1136 // and it failed.
1137 uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1138 return !already_trapped;
1139 }
1140
1141
1142 //------------------------------flatten_alias_type-----------------------------
1143 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1144 int offset = tj->offset();
1145 TypePtr::PTR ptr = tj->ptr();
1146
1147 // Known instance (scalarizable allocation) alias only with itself.
1148 bool is_known_inst = tj->isa_oopptr() != NULL &&
1149 tj->is_oopptr()->is_known_instance();
1150
1151 // Process weird unsafe references.
1152 if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1153 assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
1154 assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1155 tj = TypeOopPtr::BOTTOM;
1156 ptr = tj->ptr();
1157 offset = tj->offset();
1158 }
1159
1160 // Array pointers need some flattening
1161 const TypeAryPtr *ta = tj->isa_aryptr();
1162 if( ta && is_known_inst ) {
1163 if ( offset != Type::OffsetBot &&
1164 offset > arrayOopDesc::length_offset_in_bytes() ) {
1165 offset = Type::OffsetBot; // Flatten constant access into array body only
1166 tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
1167 }
1168 } else if( ta && _AliasLevel >= 2 ) {
1169 // For arrays indexed by constant indices, we flatten the alias
1170 // space to include all of the array body. Only the header, klass
1171 // and array length can be accessed un-aliased.
1172 if( offset != Type::OffsetBot ) {
1173 if( ta->const_oop() ) { // methodDataOop or methodOop
1174 offset = Type::OffsetBot; // Flatten constant access into array body
1175 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
1176 } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1177 // range is OK as-is.
1178 tj = ta = TypeAryPtr::RANGE;
1179 } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1180 tj = TypeInstPtr::KLASS; // all klass loads look alike
1181 ta = TypeAryPtr::RANGE; // generic ignored junk
1182 ptr = TypePtr::BotPTR;
1183 } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1184 tj = TypeInstPtr::MARK;
1185 ta = TypeAryPtr::RANGE; // generic ignored junk
1186 ptr = TypePtr::BotPTR;
1187 } else { // Random constant offset into array body
1188 offset = Type::OffsetBot; // Flatten constant access into array body
1189 tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
1190 }
1191 }
1192 // Arrays of fixed size alias with arrays of unknown size.
1193 if (ta->size() != TypeInt::POS) {
1194 const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1195 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
1196 }
1197 // Arrays of known objects become arrays of unknown objects.
1198 if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1199 const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1200 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1201 }
1202 if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1203 const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1204 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1205 }
1206 // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1207 // cannot be distinguished by bytecode alone.
1208 if (ta->elem() == TypeInt::BOOL) {
1209 const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1210 ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1211 tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
1212 }
1213 // During the 2nd round of IterGVN, NotNull castings are removed.
1214 // Make sure the Bottom and NotNull variants alias the same.
1215 // Also, make sure exact and non-exact variants alias the same.
1216 if( ptr == TypePtr::NotNull || ta->klass_is_exact() ) {
1217 tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
1218 }
1219 }
1220
1221 // Oop pointers need some flattening
1222 const TypeInstPtr *to = tj->isa_instptr();
1223 if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
1224 ciInstanceKlass *k = to->klass()->as_instance_klass();
1225 if( ptr == TypePtr::Constant ) {
1226 if (to->klass() != ciEnv::current()->Class_klass() ||
1227 offset < k->size_helper() * wordSize) {
1228 // No constant oop pointers (such as Strings); they alias with
1229 // unknown strings.
1230 assert(!is_known_inst, "not scalarizable allocation");
1231 tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1232 }
1233 } else if( is_known_inst ) {
1234 tj = to; // Keep NotNull and klass_is_exact for instance type
1235 } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1236 // During the 2nd round of IterGVN, NotNull castings are removed.
1237 // Make sure the Bottom and NotNull variants alias the same.
1238 // Also, make sure exact and non-exact variants alias the same.
1239 tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1240 }
1241 // Canonicalize the holder of this field
1242 if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1243 // First handle header references such as a LoadKlassNode, even if the
1244 // object's klass is unloaded at compile time (4965979).
1245 if (!is_known_inst) { // Do it only for non-instance types
1246 tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
1247 }
1248 } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
1249 // Static fields are in the space above the normal instance
1250 // fields in the java.lang.Class instance.
1251 if (to->klass() != ciEnv::current()->Class_klass()) {
1252 to = NULL;
1253 tj = TypeOopPtr::BOTTOM;
1254 offset = tj->offset();
1255 }
1256 } else {
1257 ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
1258 if (!k->equals(canonical_holder) || tj->offset() != offset) {
1259 if( is_known_inst ) {
1260 tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
1261 } else {
1262 tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
1263 }
1264 }
1265 }
1266 }
1267
1268 // Klass pointers to object array klasses need some flattening
1269 const TypeKlassPtr *tk = tj->isa_klassptr();
1270 if( tk ) {
1271 // If we are referencing a field within a Klass, we need
1272 // to assume the worst case of an Object. Both exact and
1273 // inexact types must flatten to the same alias class.
1274 // Since the flattened result for a klass is defined to be
1275 // precisely java.lang.Object, use a constant ptr.
1276 if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1277
1278 tj = tk = TypeKlassPtr::make(TypePtr::Constant,
1279 TypeKlassPtr::OBJECT->klass(),
1280 offset);
1281 }
1282
1283 ciKlass* klass = tk->klass();
1284 if( klass->is_obj_array_klass() ) {
1285 ciKlass* k = TypeAryPtr::OOPS->klass();
1286 if( !k || !k->is_loaded() ) // Only fails for some -Xcomp runs
1287 k = TypeInstPtr::BOTTOM->klass();
1288 tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
1289 }
1290
1291 // Check for precise loads from the primary supertype array and force them
1292 // to the supertype cache alias index. Check for generic array loads from
1293 // the primary supertype array and also force them to the supertype cache
1294 // alias index. Since the same load can reach both, we need to merge
1295 // these 2 disparate memories into the same alias class. Since the
1296 // primary supertype array is read-only, there's no chance of confusion
1297 // where we bypass an array load and an array store.
1298 uint off2 = offset - Klass::primary_supers_offset_in_bytes();
1299 if( offset == Type::OffsetBot ||
1300 off2 < Klass::primary_super_limit()*wordSize ) {
1301 offset = sizeof(oopDesc) +Klass::secondary_super_cache_offset_in_bytes();
1302 tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
1303 }
1304 }
1305
1306 // Flatten all Raw pointers together.
1307 if (tj->base() == Type::RawPtr)
1308 tj = TypeRawPtr::BOTTOM;
1309
1310 if (tj->base() == Type::AnyPtr)
1311 tj = TypePtr::BOTTOM; // An error, which the caller must check for.
1312
1313 // Flatten all to bottom for now
1314 switch( _AliasLevel ) {
1315 case 0:
1316 tj = TypePtr::BOTTOM;
1317 break;
1318 case 1: // Flatten to: oop, static, field or array
1319 switch (tj->base()) {
1320 //case Type::AryPtr: tj = TypeAryPtr::RANGE; break;
1321 case Type::RawPtr: tj = TypeRawPtr::BOTTOM; break;
1322 case Type::AryPtr: // do not distinguish arrays at all
1323 case Type::InstPtr: tj = TypeInstPtr::BOTTOM; break;
1324 case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
1325 case Type::AnyPtr: tj = TypePtr::BOTTOM; break; // caller checks it
1326 default: ShouldNotReachHere();
1327 }
1328 break;
1329 case 2: // No collapsing at level 2; keep all splits
1330 case 3: // No collapsing at level 3; keep all splits
1331 break;
1332 default:
1333 Unimplemented();
1334 }
1335
1336 offset = tj->offset();
1337 assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1338
1339 assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1340 (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1341 (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1342 (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1343 (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1344 (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1345 (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr) ,
1346 "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1347 assert( tj->ptr() != TypePtr::TopPTR &&
1348 tj->ptr() != TypePtr::AnyNull &&
1349 tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1350 // assert( tj->ptr() != TypePtr::Constant ||
1351 // tj->base() == Type::RawPtr ||
1352 // tj->base() == Type::KlassPtr, "No constant oop addresses" );
1353
1354 return tj;
1355 }
1356
1357 void Compile::AliasType::Init(int i, const TypePtr* at) {
1358 _index = i;
1359 _adr_type = at;
1360 _field = NULL;
1361 _is_rewritable = true; // default
1362 const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
1363 if (atoop != NULL && atoop->is_known_instance()) {
1364 const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1365 _general_index = Compile::current()->get_alias_index(gt);
1366 } else {
1367 _general_index = 0;
1368 }
1369 }
1370
1371 //---------------------------------print_on------------------------------------
1372 #ifndef PRODUCT
1373 void Compile::AliasType::print_on(outputStream* st) {
1374 if (index() < 10)
1375 st->print("@ <%d> ", index());
1376 else st->print("@ <%d>", index());
1377 st->print(is_rewritable() ? " " : " RO");
1378 int offset = adr_type()->offset();
1379 if (offset == Type::OffsetBot)
1380 st->print(" +any");
1381 else st->print(" +%-3d", offset);
1382 st->print(" in ");
1383 adr_type()->dump_on(st);
1384 const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1385 if (field() != NULL && tjp) {
1386 if (tjp->klass() != field()->holder() ||
1387 tjp->offset() != field()->offset_in_bytes()) {
1388 st->print(" != ");
1389 field()->print();
1390 st->print(" ***");
1391 }
1392 }
1393 }
1394
1395 void print_alias_types() {
1396 Compile* C = Compile::current();
1397 tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1398 for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1399 C->alias_type(idx)->print_on(tty);
1400 tty->cr();
1401 }
1402 }
1403 #endif
1404
1405
1406 //----------------------------probe_alias_cache--------------------------------
1407 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1408 intptr_t key = (intptr_t) adr_type;
1409 key ^= key >> logAliasCacheSize;
1410 return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1411 }
1412
1413
1414 //-----------------------------grow_alias_types--------------------------------
1415 void Compile::grow_alias_types() {
1416 const int old_ats = _max_alias_types; // how many before?
1417 const int new_ats = old_ats; // how many more?
1418 const int grow_ats = old_ats+new_ats; // how many now?
1419 _max_alias_types = grow_ats;
1420 _alias_types = REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1421 AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1422 Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1423 for (int i = 0; i < new_ats; i++) _alias_types[old_ats+i] = &ats[i];
1424 }
1425
1426
1427 //--------------------------------find_alias_type------------------------------
1428 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1429 if (_AliasLevel == 0)
1430 return alias_type(AliasIdxBot);
1431
1432 AliasCacheEntry* ace = probe_alias_cache(adr_type);
1433 if (ace->_adr_type == adr_type) {
1434 return alias_type(ace->_index);
1435 }
1436
1437 // Handle special cases.
1438 if (adr_type == NULL) return alias_type(AliasIdxTop);
1439 if (adr_type == TypePtr::BOTTOM) return alias_type(AliasIdxBot);
1440
1441 // Do it the slow way.
1442 const TypePtr* flat = flatten_alias_type(adr_type);
1443
1444 #ifdef ASSERT
1445 assert(flat == flatten_alias_type(flat), "idempotent");
1446 assert(flat != TypePtr::BOTTOM, "cannot alias-analyze an untyped ptr");
1447 if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1448 const TypeOopPtr* foop = flat->is_oopptr();
1449 // Scalarizable allocations have exact klass always.
1450 bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1451 const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1452 assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type");
1453 }
1454 assert(flat == flatten_alias_type(flat), "exact bit doesn't matter");
1455 #endif
1456
1457 int idx = AliasIdxTop;
1458 for (int i = 0; i < num_alias_types(); i++) {
1459 if (alias_type(i)->adr_type() == flat) {
1460 idx = i;
1461 break;
1462 }
1463 }
1464
1465 if (idx == AliasIdxTop) {
1466 if (no_create) return NULL;
1467 // Grow the array if necessary.
1468 if (_num_alias_types == _max_alias_types) grow_alias_types();
1469 // Add a new alias type.
1470 idx = _num_alias_types++;
1471 _alias_types[idx]->Init(idx, flat);
1472 if (flat == TypeInstPtr::KLASS) alias_type(idx)->set_rewritable(false);
1473 if (flat == TypeAryPtr::RANGE) alias_type(idx)->set_rewritable(false);
1474 if (flat->isa_instptr()) {
1475 if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
1476 && flat->is_instptr()->klass() == env()->Class_klass())
1477 alias_type(idx)->set_rewritable(false);
1478 }
1479 if (flat->isa_klassptr()) {
1480 if (flat->offset() == Klass::super_check_offset_offset_in_bytes() + (int)sizeof(oopDesc))
1481 alias_type(idx)->set_rewritable(false);
1482 if (flat->offset() == Klass::modifier_flags_offset_in_bytes() + (int)sizeof(oopDesc))
1483 alias_type(idx)->set_rewritable(false);
1484 if (flat->offset() == Klass::access_flags_offset_in_bytes() + (int)sizeof(oopDesc))
1485 alias_type(idx)->set_rewritable(false);
1486 if (flat->offset() == Klass::java_mirror_offset_in_bytes() + (int)sizeof(oopDesc))
1487 alias_type(idx)->set_rewritable(false);
1488 }
1489 // %%% (We would like to finalize JavaThread::threadObj_offset(),
1490 // but the base pointer type is not distinctive enough to identify
1491 // references into JavaThread.)
1492
1493 // Check for final fields.
1494 const TypeInstPtr* tinst = flat->isa_instptr();
1495 if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1496 ciField* field;
1497 if (tinst->const_oop() != NULL &&
1498 tinst->klass() == ciEnv::current()->Class_klass() &&
1499 tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
1500 // static field
1501 ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1502 field = k->get_field_by_offset(tinst->offset(), true);
1503 } else {
1504 ciInstanceKlass *k = tinst->klass()->as_instance_klass();
1505 field = k->get_field_by_offset(tinst->offset(), false);
1506 }
1507 assert(field == NULL ||
1508 original_field == NULL ||
1509 (field->holder() == original_field->holder() &&
1510 field->offset() == original_field->offset() &&
1511 field->is_static() == original_field->is_static()), "wrong field?");
1512 // Set field() and is_rewritable() attributes.
1513 if (field != NULL) alias_type(idx)->set_field(field);
1514 }
1515 }
1516
1517 // Fill the cache for next time.
1518 ace->_adr_type = adr_type;
1519 ace->_index = idx;
1520 assert(alias_type(adr_type) == alias_type(idx), "type must be installed");
1521
1522 // Might as well try to fill the cache for the flattened version, too.
1523 AliasCacheEntry* face = probe_alias_cache(flat);
1524 if (face->_adr_type == NULL) {
1525 face->_adr_type = flat;
1526 face->_index = idx;
1527 assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1528 }
1529
1530 return alias_type(idx);
1531 }
1532
1533
1534 Compile::AliasType* Compile::alias_type(ciField* field) {
1535 const TypeOopPtr* t;
1536 if (field->is_static())
1537 t = TypeInstPtr::make(field->holder()->java_mirror());
1538 else
1539 t = TypeOopPtr::make_from_klass_raw(field->holder());
1540 AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1541 assert(field->is_final() == !atp->is_rewritable(), "must get the rewritable bits correct");
1542 return atp;
1543 }
1544
1545
1546 //------------------------------have_alias_type--------------------------------
1547 bool Compile::have_alias_type(const TypePtr* adr_type) {
1548 AliasCacheEntry* ace = probe_alias_cache(adr_type);
1549 if (ace->_adr_type == adr_type) {
1550 return true;
1551 }
1552
1553 // Handle special cases.
1554 if (adr_type == NULL) return true;
1555 if (adr_type == TypePtr::BOTTOM) return true;
1556
1557 return find_alias_type(adr_type, true, NULL) != NULL;
1558 }
1559
1560 //-----------------------------must_alias--------------------------------------
1561 // True if all values of the given address type are in the given alias category.
1562 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1563 if (alias_idx == AliasIdxBot) return true; // the universal category
1564 if (adr_type == NULL) return true; // NULL serves as TypePtr::TOP
1565 if (alias_idx == AliasIdxTop) return false; // the empty category
1566 if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1567
1568 // the only remaining possible overlap is identity
1569 int adr_idx = get_alias_index(adr_type);
1570 assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1571 assert(adr_idx == alias_idx ||
1572 (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1573 && adr_type != TypeOopPtr::BOTTOM),
1574 "should not be testing for overlap with an unsafe pointer");
1575 return adr_idx == alias_idx;
1576 }
1577
1578 //------------------------------can_alias--------------------------------------
1579 // True if any values of the given address type are in the given alias category.
1580 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1581 if (alias_idx == AliasIdxTop) return false; // the empty category
1582 if (adr_type == NULL) return false; // NULL serves as TypePtr::TOP
1583 if (alias_idx == AliasIdxBot) return true; // the universal category
1584 if (adr_type->base() == Type::AnyPtr) return true; // TypePtr::BOTTOM or its twins
1585
1586 // the only remaining possible overlap is identity
1587 int adr_idx = get_alias_index(adr_type);
1588 assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1589 return adr_idx == alias_idx;
1590 }
1591
1592
1593
1594 //---------------------------pop_warm_call-------------------------------------
1595 WarmCallInfo* Compile::pop_warm_call() {
1596 WarmCallInfo* wci = _warm_calls;
1597 if (wci != NULL) _warm_calls = wci->remove_from(wci);
1598 return wci;
1599 }
1600
1601 //----------------------------Inline_Warm--------------------------------------
1602 int Compile::Inline_Warm() {
1603 // If there is room, try to inline some more warm call sites.
1604 // %%% Do a graph index compaction pass when we think we're out of space?
1605 if (!InlineWarmCalls) return 0;
1606
1607 int calls_made_hot = 0;
1608 int room_to_grow = NodeCountInliningCutoff - unique();
1609 int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
1610 int amount_grown = 0;
1611 WarmCallInfo* call;
1612 while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
1613 int est_size = (int)call->size();
1614 if (est_size > (room_to_grow - amount_grown)) {
1615 // This one won't fit anyway. Get rid of it.
1616 call->make_cold();
1617 continue;
1618 }
1619 call->make_hot();
1620 calls_made_hot++;
1621 amount_grown += est_size;
1622 amount_to_grow -= est_size;
1623 }
1624
1625 if (calls_made_hot > 0) set_major_progress();
1626 return calls_made_hot;
1627 }
1628
1629
1630 //----------------------------Finish_Warm--------------------------------------
1631 void Compile::Finish_Warm() {
1632 if (!InlineWarmCalls) return;
1633 if (failing()) return;
1634 if (warm_calls() == NULL) return;
1635
1636 // Clean up loose ends, if we are out of space for inlining.
1637 WarmCallInfo* call;
1638 while ((call = pop_warm_call()) != NULL) {
1639 call->make_cold();
1640 }
1641 }
1642
1643 //---------------------cleanup_loop_predicates-----------------------
1644 // Remove the opaque nodes that protect the predicates so that all unused
1645 // checks and uncommon_traps will be eliminated from the ideal graph
1646 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
1647 if (predicate_count()==0) return;
1648 for (int i = predicate_count(); i > 0; i--) {
1649 Node * n = predicate_opaque1_node(i-1);
1650 assert(n->Opcode() == Op_Opaque1, "must be");
1651 igvn.replace_node(n, n->in(1));
1652 }
1653 assert(predicate_count()==0, "should be clean!");
1654 }
1655
1656 //------------------------------Optimize---------------------------------------
1657 // Given a graph, optimize it.
1658 void Compile::Optimize() {
1659 TracePhase t1("optimizer", &_t_optimizer, true);
1660
1661 #ifndef PRODUCT
1662 if (env()->break_at_compile()) {
1663 BREAKPOINT;
1664 }
1665
1666 #endif
1667
1668 ResourceMark rm;
1669 int loop_opts_cnt;
1670
1671 NOT_PRODUCT( verify_graph_edges(); )
1672
1673 print_method("After Parsing");
1674
1675 {
1676 // Iterative Global Value Numbering, including ideal transforms
1677 // Initialize IterGVN with types and values from parse-time GVN
1678 PhaseIterGVN igvn(initial_gvn());
1679 {
1680 NOT_PRODUCT( TracePhase t2("iterGVN", &_t_iterGVN, TimeCompiler); )
1681 igvn.optimize();
1682 }
1683
1684 print_method("Iter GVN 1", 2);
1685
1686 if (failing()) return;
1687
1688 // Perform escape analysis
1689 if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
1690 TracePhase t2("escapeAnalysis", &_t_escapeAnalysis, true);
1691 ConnectionGraph::do_analysis(this, &igvn);
1692
1693 if (failing()) return;
1694
1695 igvn.optimize();
1696 print_method("Iter GVN 3", 2);
1697
1698 if (failing()) return;
1699
1700 }
1701
1702 // Loop transforms on the ideal graph. Range Check Elimination,
1703 // peeling, unrolling, etc.
1704
1705 // Set loop opts counter
1706 loop_opts_cnt = num_loop_opts();
1707 if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
1708 {
1709 TracePhase t2("idealLoop", &_t_idealLoop, true);
1710 PhaseIdealLoop ideal_loop( igvn, true );
1711 loop_opts_cnt--;
1712 if (major_progress()) print_method("PhaseIdealLoop 1", 2);
1713 if (failing()) return;
1714 }
1715 // Loop opts pass if partial peeling occurred in previous pass
1716 if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
1717 TracePhase t3("idealLoop", &_t_idealLoop, true);
1718 PhaseIdealLoop ideal_loop( igvn, false );
1719 loop_opts_cnt--;
1720 if (major_progress()) print_method("PhaseIdealLoop 2", 2);
1721 if (failing()) return;
1722 }
1723 // Loop opts pass for loop-unrolling before CCP
1724 if(major_progress() && (loop_opts_cnt > 0)) {
1725 TracePhase t4("idealLoop", &_t_idealLoop, true);
1726 PhaseIdealLoop ideal_loop( igvn, false );
1727 loop_opts_cnt--;
1728 if (major_progress()) print_method("PhaseIdealLoop 3", 2);
1729 }
1730 if (!failing()) {
1731 // Verify that last round of loop opts produced a valid graph
1732 NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
1733 PhaseIdealLoop::verify(igvn);
1734 }
1735 }
1736 if (failing()) return;
1737
1738 // Conditional Constant Propagation;
1739 PhaseCCP ccp( &igvn );
1740 assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
1741 {
1742 TracePhase t2("ccp", &_t_ccp, true);
1743 ccp.do_transform();
1744 }
1745 print_method("PhaseCPP 1", 2);
1746
1747 assert( true, "Break here to ccp.dump_old2new_map()");
1748
1749 // Iterative Global Value Numbering, including ideal transforms
1750 {
1751 NOT_PRODUCT( TracePhase t2("iterGVN2", &_t_iterGVN2, TimeCompiler); )
1752 igvn = ccp;
1753 igvn.optimize();
1754 }
1755
1756 print_method("Iter GVN 2", 2);
1757
1758 if (failing()) return;
1759
1760 // Loop transforms on the ideal graph. Range Check Elimination,
1761 // peeling, unrolling, etc.
1762 if(loop_opts_cnt > 0) {
1763 debug_only( int cnt = 0; );
1764 while(major_progress() && (loop_opts_cnt > 0)) {
1765 TracePhase t2("idealLoop", &_t_idealLoop, true);
1766 assert( cnt++ < 40, "infinite cycle in loop optimization" );
1767 PhaseIdealLoop ideal_loop( igvn, true);
1768 loop_opts_cnt--;
1769 if (major_progress()) print_method("PhaseIdealLoop iterations", 2);
1770 if (failing()) return;
1771 }
1772 }
1773
1774 {
1775 // Verify that all previous optimizations produced a valid graph
1776 // at least to this point, even if no loop optimizations were done.
1777 NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
1778 PhaseIdealLoop::verify(igvn);
1779 }
1780
1781 {
1782 NOT_PRODUCT( TracePhase t2("macroExpand", &_t_macroExpand, TimeCompiler); )
1783 PhaseMacroExpand mex(igvn);
1784 if (mex.expand_macro_nodes()) {
1785 assert(failing(), "must bail out w/ explicit message");
1786 return;
1787 }
1788 }
1789
1790 } // (End scope of igvn; run destructor if necessary for asserts.)
1791
1792 // A method with only infinite loops has no edges entering loops from root
1793 {
1794 NOT_PRODUCT( TracePhase t2("graphReshape", &_t_graphReshaping, TimeCompiler); )
1795 if (final_graph_reshaping()) {
1796 assert(failing(), "must bail out w/ explicit message");
1797 return;
1798 }
1799 }
1800
1801 print_method("Optimize finished", 2);
1802 }
1803
1804
1805 //------------------------------Code_Gen---------------------------------------
1806 // Given a graph, generate code for it
1807 void Compile::Code_Gen() {
1808 if (failing()) return;
1809
1810 // Perform instruction selection. You might think we could reclaim Matcher
1811 // memory PDQ, but actually the Matcher is used in generating spill code.
1812 // Internals of the Matcher (including some VectorSets) must remain live
1813 // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
1814 // set a bit in reclaimed memory.
1815
1816 // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
1817 // nodes. Mapping is only valid at the root of each matched subtree.
1818 NOT_PRODUCT( verify_graph_edges(); )
1819
1820 Node_List proj_list;
1821 Matcher m(proj_list);
1822 _matcher = &m;
1823 {
1824 TracePhase t2("matcher", &_t_matcher, true);
1825 m.match();
1826 }
1827 // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
1828 // nodes. Mapping is only valid at the root of each matched subtree.
1829 NOT_PRODUCT( verify_graph_edges(); )
1830
1831 // If you have too many nodes, or if matching has failed, bail out
1832 check_node_count(0, "out of nodes matching instructions");
1833 if (failing()) return;
1834
1835 // Build a proper-looking CFG
1836 PhaseCFG cfg(node_arena(), root(), m);
1837 _cfg = &cfg;
1838 {
1839 NOT_PRODUCT( TracePhase t2("scheduler", &_t_scheduler, TimeCompiler); )
1840 cfg.Dominators();
1841 if (failing()) return;
1842
1843 NOT_PRODUCT( verify_graph_edges(); )
1844
1845 cfg.Estimate_Block_Frequency();
1846 cfg.GlobalCodeMotion(m,unique(),proj_list);
1847
1848 print_method("Global code motion", 2);
1849
1850 if (failing()) return;
1851 NOT_PRODUCT( verify_graph_edges(); )
1852
1853 debug_only( cfg.verify(); )
1854 }
1855 NOT_PRODUCT( verify_graph_edges(); )
1856
1857 PhaseChaitin regalloc(unique(),cfg,m);
1858 _regalloc = ®alloc;
1859 {
1860 TracePhase t2("regalloc", &_t_registerAllocation, true);
1861 // Perform any platform dependent preallocation actions. This is used,
1862 // for example, to avoid taking an implicit null pointer exception
1863 // using the frame pointer on win95.
1864 _regalloc->pd_preallocate_hook();
1865
1866 // Perform register allocation. After Chaitin, use-def chains are
1867 // no longer accurate (at spill code) and so must be ignored.
1868 // Node->LRG->reg mappings are still accurate.
1869 _regalloc->Register_Allocate();
1870
1871 // Bail out if the allocator builds too many nodes
1872 if (failing()) return;
1873 }
1874
1875 // Prior to register allocation we kept empty basic blocks in case the
1876 // the allocator needed a place to spill. After register allocation we
1877 // are not adding any new instructions. If any basic block is empty, we
1878 // can now safely remove it.
1879 {
1880 NOT_PRODUCT( TracePhase t2("blockOrdering", &_t_blockOrdering, TimeCompiler); )
1881 cfg.remove_empty();
1882 if (do_freq_based_layout()) {
1883 PhaseBlockLayout layout(cfg);
1884 } else {
1885 cfg.set_loop_alignment();
1886 }
1887 cfg.fixup_flow();
1888 }
1889
1890 // Perform any platform dependent postallocation verifications.
1891 debug_only( _regalloc->pd_postallocate_verify_hook(); )
1892
1893 // Apply peephole optimizations
1894 if( OptoPeephole ) {
1895 NOT_PRODUCT( TracePhase t2("peephole", &_t_peephole, TimeCompiler); )
1896 PhasePeephole peep( _regalloc, cfg);
1897 peep.do_transform();
1898 }
1899
1900 // Convert Nodes to instruction bits in a buffer
1901 {
1902 // %%%% workspace merge brought two timers together for one job
1903 TracePhase t2a("output", &_t_output, true);
1904 NOT_PRODUCT( TraceTime t2b(NULL, &_t_codeGeneration, TimeCompiler, false); )
1905 Output();
1906 }
1907
1908 print_method("Final Code");
1909
1910 // He's dead, Jim.
1911 _cfg = (PhaseCFG*)0xdeadbeef;
1912 _regalloc = (PhaseChaitin*)0xdeadbeef;
1913 }
1914
1915
1916 //------------------------------dump_asm---------------------------------------
1917 // Dump formatted assembly
1918 #ifndef PRODUCT
1919 void Compile::dump_asm(int *pcs, uint pc_limit) {
1920 bool cut_short = false;
1921 tty->print_cr("#");
1922 tty->print("# "); _tf->dump(); tty->cr();
1923 tty->print_cr("#");
1924
1925 // For all blocks
1926 int pc = 0x0; // Program counter
1927 char starts_bundle = ' ';
1928 _regalloc->dump_frame();
1929
1930 Node *n = NULL;
1931 for( uint i=0; i<_cfg->_num_blocks; i++ ) {
1932 if (VMThread::should_terminate()) { cut_short = true; break; }
1933 Block *b = _cfg->_blocks[i];
1934 if (b->is_connector() && !Verbose) continue;
1935 n = b->_nodes[0];
1936 if (pcs && n->_idx < pc_limit)
1937 tty->print("%3.3x ", pcs[n->_idx]);
1938 else
1939 tty->print(" ");
1940 b->dump_head( &_cfg->_bbs );
1941 if (b->is_connector()) {
1942 tty->print_cr(" # Empty connector block");
1943 } else if (b->num_preds() == 2 && b->pred(1)->is_CatchProj() && b->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
1944 tty->print_cr(" # Block is sole successor of call");
1945 }
1946
1947 // For all instructions
1948 Node *delay = NULL;
1949 for( uint j = 0; j<b->_nodes.size(); j++ ) {
1950 if (VMThread::should_terminate()) { cut_short = true; break; }
1951 n = b->_nodes[j];
1952 if (valid_bundle_info(n)) {
1953 Bundle *bundle = node_bundling(n);
1954 if (bundle->used_in_unconditional_delay()) {
1955 delay = n;
1956 continue;
1957 }
1958 if (bundle->starts_bundle())
1959 starts_bundle = '+';
1960 }
1961
1962 if (WizardMode) n->dump();
1963
1964 if( !n->is_Region() && // Dont print in the Assembly
1965 !n->is_Phi() && // a few noisely useless nodes
1966 !n->is_Proj() &&
1967 !n->is_MachTemp() &&
1968 !n->is_SafePointScalarObject() &&
1969 !n->is_Catch() && // Would be nice to print exception table targets
1970 !n->is_MergeMem() && // Not very interesting
1971 !n->is_top() && // Debug info table constants
1972 !(n->is_Con() && !n->is_Mach())// Debug info table constants
1973 ) {
1974 if (pcs && n->_idx < pc_limit)
1975 tty->print("%3.3x", pcs[n->_idx]);
1976 else
1977 tty->print(" ");
1978 tty->print(" %c ", starts_bundle);
1979 starts_bundle = ' ';
1980 tty->print("\t");
1981 n->format(_regalloc, tty);
1982 tty->cr();
1983 }
1984
1985 // If we have an instruction with a delay slot, and have seen a delay,
1986 // then back up and print it
1987 if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
1988 assert(delay != NULL, "no unconditional delay instruction");
1989 if (WizardMode) delay->dump();
1990
1991 if (node_bundling(delay)->starts_bundle())
1992 starts_bundle = '+';
1993 if (pcs && n->_idx < pc_limit)
1994 tty->print("%3.3x", pcs[n->_idx]);
1995 else
1996 tty->print(" ");
1997 tty->print(" %c ", starts_bundle);
1998 starts_bundle = ' ';
1999 tty->print("\t");
2000 delay->format(_regalloc, tty);
2001 tty->print_cr("");
2002 delay = NULL;
2003 }
2004
2005 // Dump the exception table as well
2006 if( n->is_Catch() && (Verbose || WizardMode) ) {
2007 // Print the exception table for this offset
2008 _handler_table.print_subtable_for(pc);
2009 }
2010 }
2011
2012 if (pcs && n->_idx < pc_limit)
2013 tty->print_cr("%3.3x", pcs[n->_idx]);
2014 else
2015 tty->print_cr("");
2016
2017 assert(cut_short || delay == NULL, "no unconditional delay branch");
2018
2019 } // End of per-block dump
2020 tty->print_cr("");
2021
2022 if (cut_short) tty->print_cr("*** disassembly is cut short ***");
2023 }
2024 #endif
2025
2026 //------------------------------Final_Reshape_Counts---------------------------
2027 // This class defines counters to help identify when a method
2028 // may/must be executed using hardware with only 24-bit precision.
2029 struct Final_Reshape_Counts : public StackObj {
2030 int _call_count; // count non-inlined 'common' calls
2031 int _float_count; // count float ops requiring 24-bit precision
2032 int _double_count; // count double ops requiring more precision
2033 int _java_call_count; // count non-inlined 'java' calls
2034 int _inner_loop_count; // count loops which need alignment
2035 VectorSet _visited; // Visitation flags
2036 Node_List _tests; // Set of IfNodes & PCTableNodes
2037
2038 Final_Reshape_Counts() :
2039 _call_count(0), _float_count(0), _double_count(0),
2040 _java_call_count(0), _inner_loop_count(0),
2041 _visited( Thread::current()->resource_area() ) { }
2042
2043 void inc_call_count () { _call_count ++; }
2044 void inc_float_count () { _float_count ++; }
2045 void inc_double_count() { _double_count++; }
2046 void inc_java_call_count() { _java_call_count++; }
2047 void inc_inner_loop_count() { _inner_loop_count++; }
2048
2049 int get_call_count () const { return _call_count ; }
2050 int get_float_count () const { return _float_count ; }
2051 int get_double_count() const { return _double_count; }
2052 int get_java_call_count() const { return _java_call_count; }
2053 int get_inner_loop_count() const { return _inner_loop_count; }
2054 };
2055
2056 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
2057 ciInstanceKlass *k = tp->klass()->as_instance_klass();
2058 // Make sure the offset goes inside the instance layout.
2059 return k->contains_field_offset(tp->offset());
2060 // Note that OffsetBot and OffsetTop are very negative.
2061 }
2062
2063 // Eliminate trivially redundant StoreCMs and accumulate their
2064 // precedence edges.
2065 static void eliminate_redundant_card_marks(Node* n) {
2066 assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
2067 if (n->in(MemNode::Address)->outcnt() > 1) {
2068 // There are multiple users of the same address so it might be
2069 // possible to eliminate some of the StoreCMs
2070 Node* mem = n->in(MemNode::Memory);
2071 Node* adr = n->in(MemNode::Address);
2072 Node* val = n->in(MemNode::ValueIn);
2073 Node* prev = n;
2074 bool done = false;
2075 // Walk the chain of StoreCMs eliminating ones that match. As
2076 // long as it's a chain of single users then the optimization is
2077 // safe. Eliminating partially redundant StoreCMs would require
2078 // cloning copies down the other paths.
2079 while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
2080 if (adr == mem->in(MemNode::Address) &&
2081 val == mem->in(MemNode::ValueIn)) {
2082 // redundant StoreCM
2083 if (mem->req() > MemNode::OopStore) {
2084 // Hasn't been processed by this code yet.
2085 n->add_prec(mem->in(MemNode::OopStore));
2086 } else {
2087 // Already converted to precedence edge
2088 for (uint i = mem->req(); i < mem->len(); i++) {
2089 // Accumulate any precedence edges
2090 if (mem->in(i) != NULL) {
2091 n->add_prec(mem->in(i));
2092 }
2093 }
2094 // Everything above this point has been processed.
2095 done = true;
2096 }
2097 // Eliminate the previous StoreCM
2098 prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
2099 assert(mem->outcnt() == 0, "should be dead");
2100 mem->disconnect_inputs(NULL);
2101 } else {
2102 prev = mem;
2103 }
2104 mem = prev->in(MemNode::Memory);
2105 }
2106 }
2107 }
2108
2109 //------------------------------final_graph_reshaping_impl----------------------
2110 // Implement items 1-5 from final_graph_reshaping below.
2111 static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
2112
2113 if ( n->outcnt() == 0 ) return; // dead node
2114 uint nop = n->Opcode();
2115
2116 // Check for 2-input instruction with "last use" on right input.
2117 // Swap to left input. Implements item (2).
2118 if( n->req() == 3 && // two-input instruction
2119 n->in(1)->outcnt() > 1 && // left use is NOT a last use
2120 (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
2121 n->in(2)->outcnt() == 1 &&// right use IS a last use
2122 !n->in(2)->is_Con() ) { // right use is not a constant
2123 // Check for commutative opcode
2124 switch( nop ) {
2125 case Op_AddI: case Op_AddF: case Op_AddD: case Op_AddL:
2126 case Op_MaxI: case Op_MinI:
2127 case Op_MulI: case Op_MulF: case Op_MulD: case Op_MulL:
2128 case Op_AndL: case Op_XorL: case Op_OrL:
2129 case Op_AndI: case Op_XorI: case Op_OrI: {
2130 // Move "last use" input to left by swapping inputs
2131 n->swap_edges(1, 2);
2132 break;
2133 }
2134 default:
2135 break;
2136 }
2137 }
2138
2139 #ifdef ASSERT
2140 if( n->is_Mem() ) {
2141 Compile* C = Compile::current();
2142 int alias_idx = C->get_alias_index(n->as_Mem()->adr_type());
2143 assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
2144 // oop will be recorded in oop map if load crosses safepoint
2145 n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
2146 LoadNode::is_immutable_value(n->in(MemNode::Address))),
2147 "raw memory operations should have control edge");
2148 }
2149 #endif
2150 // Count FPU ops and common calls, implements item (3)
2151 switch( nop ) {
2152 // Count all float operations that may use FPU
2153 case Op_AddF:
2154 case Op_SubF:
2155 case Op_MulF:
2156 case Op_DivF:
2157 case Op_NegF:
2158 case Op_ModF:
2159 case Op_ConvI2F:
2160 case Op_ConF:
2161 case Op_CmpF:
2162 case Op_CmpF3:
2163 // case Op_ConvL2F: // longs are split into 32-bit halves
2164 frc.inc_float_count();
2165 break;
2166
2167 case Op_ConvF2D:
2168 case Op_ConvD2F:
2169 frc.inc_float_count();
2170 frc.inc_double_count();
2171 break;
2172
2173 // Count all double operations that may use FPU
2174 case Op_AddD:
2175 case Op_SubD:
2176 case Op_MulD:
2177 case Op_DivD:
2178 case Op_NegD:
2179 case Op_ModD:
2180 case Op_ConvI2D:
2181 case Op_ConvD2I:
2182 // case Op_ConvL2D: // handled by leaf call
2183 // case Op_ConvD2L: // handled by leaf call
2184 case Op_ConD:
2185 case Op_CmpD:
2186 case Op_CmpD3:
2187 frc.inc_double_count();
2188 break;
2189 case Op_Opaque1: // Remove Opaque Nodes before matching
2190 case Op_Opaque2: // Remove Opaque Nodes before matching
2191 n->subsume_by(n->in(1));
2192 break;
2193 case Op_CallStaticJava:
2194 case Op_CallJava:
2195 case Op_CallDynamicJava:
2196 frc.inc_java_call_count(); // Count java call site;
2197 case Op_CallRuntime:
2198 case Op_CallLeaf:
2199 case Op_CallLeafNoFP: {
2200 assert( n->is_Call(), "" );
2201 CallNode *call = n->as_Call();
2202 // Count call sites where the FP mode bit would have to be flipped.
2203 // Do not count uncommon runtime calls:
2204 // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
2205 // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
2206 if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
2207 frc.inc_call_count(); // Count the call site
2208 } else { // See if uncommon argument is shared
2209 Node *n = call->in(TypeFunc::Parms);
2210 int nop = n->Opcode();
2211 // Clone shared simple arguments to uncommon calls, item (1).
2212 if( n->outcnt() > 1 &&
2213 !n->is_Proj() &&
2214 nop != Op_CreateEx &&
2215 nop != Op_CheckCastPP &&
2216 nop != Op_DecodeN &&
2217 !n->is_Mem() ) {
2218 Node *x = n->clone();
2219 call->set_req( TypeFunc::Parms, x );
2220 }
2221 }
2222 break;
2223 }
2224
2225 case Op_StoreD:
2226 case Op_LoadD:
2227 case Op_LoadD_unaligned:
2228 frc.inc_double_count();
2229 goto handle_mem;
2230 case Op_StoreF:
2231 case Op_LoadF:
2232 frc.inc_float_count();
2233 goto handle_mem;
2234
2235 case Op_StoreCM:
2236 {
2237 // Convert OopStore dependence into precedence edge
2238 Node* prec = n->in(MemNode::OopStore);
2239 n->del_req(MemNode::OopStore);
2240 n->add_prec(prec);
2241 eliminate_redundant_card_marks(n);
2242 }
2243
2244 // fall through
2245
2246 case Op_StoreB:
2247 case Op_StoreC:
2248 case Op_StorePConditional:
2249 case Op_StoreI:
2250 case Op_StoreL:
2251 case Op_StoreIConditional:
2252 case Op_StoreLConditional:
2253 case Op_CompareAndSwapI:
2254 case Op_CompareAndSwapL:
2255 case Op_CompareAndSwapP:
2256 case Op_CompareAndSwapN:
2257 case Op_StoreP:
2258 case Op_StoreN:
2259 case Op_LoadB:
2260 case Op_LoadUB:
2261 case Op_LoadUS:
2262 case Op_LoadI:
2263 case Op_LoadUI2L:
2264 case Op_LoadKlass:
2265 case Op_LoadNKlass:
2266 case Op_LoadL:
2267 case Op_LoadL_unaligned:
2268 case Op_LoadPLocked:
2269 case Op_LoadLLocked:
2270 case Op_LoadP:
2271 case Op_LoadN:
2272 case Op_LoadRange:
2273 case Op_LoadS: {
2274 handle_mem:
2275 #ifdef ASSERT
2276 if( VerifyOptoOopOffsets ) {
2277 assert( n->is_Mem(), "" );
2278 MemNode *mem = (MemNode*)n;
2279 // Check to see if address types have grounded out somehow.
2280 const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
2281 assert( !tp || oop_offset_is_sane(tp), "" );
2282 }
2283 #endif
2284 break;
2285 }
2286
2287 case Op_AddP: { // Assert sane base pointers
2288 Node *addp = n->in(AddPNode::Address);
2289 assert( !addp->is_AddP() ||
2290 addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
2291 addp->in(AddPNode::Base) == n->in(AddPNode::Base),
2292 "Base pointers must match" );
2293 #ifdef _LP64
2294 if (UseCompressedOops &&
2295 addp->Opcode() == Op_ConP &&
2296 addp == n->in(AddPNode::Base) &&
2297 n->in(AddPNode::Offset)->is_Con()) {
2298 // Use addressing with narrow klass to load with offset on x86.
2299 // On sparc loading 32-bits constant and decoding it have less
2300 // instructions (4) then load 64-bits constant (7).
2301 // Do this transformation here since IGVN will convert ConN back to ConP.
2302 const Type* t = addp->bottom_type();
2303 if (t->isa_oopptr()) {
2304 Node* nn = NULL;
2305
2306 // Look for existing ConN node of the same exact type.
2307 Compile* C = Compile::current();
2308 Node* r = C->root();
2309 uint cnt = r->outcnt();
2310 for (uint i = 0; i < cnt; i++) {
2311 Node* m = r->raw_out(i);
2312 if (m!= NULL && m->Opcode() == Op_ConN &&
2313 m->bottom_type()->make_ptr() == t) {
2314 nn = m;
2315 break;
2316 }
2317 }
2318 if (nn != NULL) {
2319 // Decode a narrow oop to match address
2320 // [R12 + narrow_oop_reg<<3 + offset]
2321 nn = new (C, 2) DecodeNNode(nn, t);
2322 n->set_req(AddPNode::Base, nn);
2323 n->set_req(AddPNode::Address, nn);
2324 if (addp->outcnt() == 0) {
2325 addp->disconnect_inputs(NULL);
2326 }
2327 }
2328 }
2329 }
2330 #endif
2331 break;
2332 }
2333
2334 #ifdef _LP64
2335 case Op_CastPP:
2336 if (n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
2337 Compile* C = Compile::current();
2338 Node* in1 = n->in(1);
2339 const Type* t = n->bottom_type();
2340 Node* new_in1 = in1->clone();
2341 new_in1->as_DecodeN()->set_type(t);
2342
2343 if (!Matcher::narrow_oop_use_complex_address()) {
2344 //
2345 // x86, ARM and friends can handle 2 adds in addressing mode
2346 // and Matcher can fold a DecodeN node into address by using
2347 // a narrow oop directly and do implicit NULL check in address:
2348 //
2349 // [R12 + narrow_oop_reg<<3 + offset]
2350 // NullCheck narrow_oop_reg
2351 //
2352 // On other platforms (Sparc) we have to keep new DecodeN node and
2353 // use it to do implicit NULL check in address:
2354 //
2355 // decode_not_null narrow_oop_reg, base_reg
2356 // [base_reg + offset]
2357 // NullCheck base_reg
2358 //
2359 // Pin the new DecodeN node to non-null path on these platform (Sparc)
2360 // to keep the information to which NULL check the new DecodeN node
2361 // corresponds to use it as value in implicit_null_check().
2362 //
2363 new_in1->set_req(0, n->in(0));
2364 }
2365
2366 n->subsume_by(new_in1);
2367 if (in1->outcnt() == 0) {
2368 in1->disconnect_inputs(NULL);
2369 }
2370 }
2371 break;
2372
2373 case Op_CmpP:
2374 // Do this transformation here to preserve CmpPNode::sub() and
2375 // other TypePtr related Ideal optimizations (for example, ptr nullness).
2376 if (n->in(1)->is_DecodeN() || n->in(2)->is_DecodeN()) {
2377 Node* in1 = n->in(1);
2378 Node* in2 = n->in(2);
2379 if (!in1->is_DecodeN()) {
2380 in2 = in1;
2381 in1 = n->in(2);
2382 }
2383 assert(in1->is_DecodeN(), "sanity");
2384
2385 Compile* C = Compile::current();
2386 Node* new_in2 = NULL;
2387 if (in2->is_DecodeN()) {
2388 new_in2 = in2->in(1);
2389 } else if (in2->Opcode() == Op_ConP) {
2390 const Type* t = in2->bottom_type();
2391 if (t == TypePtr::NULL_PTR) {
2392 // Don't convert CmpP null check into CmpN if compressed
2393 // oops implicit null check is not generated.
2394 // This will allow to generate normal oop implicit null check.
2395 if (Matcher::gen_narrow_oop_implicit_null_checks())
2396 new_in2 = ConNode::make(C, TypeNarrowOop::NULL_PTR);
2397 //
2398 // This transformation together with CastPP transformation above
2399 // will generated code for implicit NULL checks for compressed oops.
2400 //
2401 // The original code after Optimize()
2402 //
2403 // LoadN memory, narrow_oop_reg
2404 // decode narrow_oop_reg, base_reg
2405 // CmpP base_reg, NULL
2406 // CastPP base_reg // NotNull
2407 // Load [base_reg + offset], val_reg
2408 //
2409 // after these transformations will be
2410 //
2411 // LoadN memory, narrow_oop_reg
2412 // CmpN narrow_oop_reg, NULL
2413 // decode_not_null narrow_oop_reg, base_reg
2414 // Load [base_reg + offset], val_reg
2415 //
2416 // and the uncommon path (== NULL) will use narrow_oop_reg directly
2417 // since narrow oops can be used in debug info now (see the code in
2418 // final_graph_reshaping_walk()).
2419 //
2420 // At the end the code will be matched to
2421 // on x86:
2422 //
2423 // Load_narrow_oop memory, narrow_oop_reg
2424 // Load [R12 + narrow_oop_reg<<3 + offset], val_reg
2425 // NullCheck narrow_oop_reg
2426 //
2427 // and on sparc:
2428 //
2429 // Load_narrow_oop memory, narrow_oop_reg
2430 // decode_not_null narrow_oop_reg, base_reg
2431 // Load [base_reg + offset], val_reg
2432 // NullCheck base_reg
2433 //
2434 } else if (t->isa_oopptr()) {
2435 new_in2 = ConNode::make(C, t->make_narrowoop());
2436 }
2437 }
2438 if (new_in2 != NULL) {
2439 Node* cmpN = new (C, 3) CmpNNode(in1->in(1), new_in2);
2440 n->subsume_by( cmpN );
2441 if (in1->outcnt() == 0) {
2442 in1->disconnect_inputs(NULL);
2443 }
2444 if (in2->outcnt() == 0) {
2445 in2->disconnect_inputs(NULL);
2446 }
2447 }
2448 }
2449 break;
2450
2451 case Op_DecodeN:
2452 assert(!n->in(1)->is_EncodeP(), "should be optimized out");
2453 // DecodeN could be pinned when it can't be fold into
2454 // an address expression, see the code for Op_CastPP above.
2455 assert(n->in(0) == NULL || !Matcher::narrow_oop_use_complex_address(), "no control");
2456 break;
2457
2458 case Op_EncodeP: {
2459 Node* in1 = n->in(1);
2460 if (in1->is_DecodeN()) {
2461 n->subsume_by(in1->in(1));
2462 } else if (in1->Opcode() == Op_ConP) {
2463 Compile* C = Compile::current();
2464 const Type* t = in1->bottom_type();
2465 if (t == TypePtr::NULL_PTR) {
2466 n->subsume_by(ConNode::make(C, TypeNarrowOop::NULL_PTR));
2467 } else if (t->isa_oopptr()) {
2468 n->subsume_by(ConNode::make(C, t->make_narrowoop()));
2469 }
2470 }
2471 if (in1->outcnt() == 0) {
2472 in1->disconnect_inputs(NULL);
2473 }
2474 break;
2475 }
2476
2477 case Op_Proj: {
2478 if (OptimizeStringConcat) {
2479 ProjNode* p = n->as_Proj();
2480 if (p->_is_io_use) {
2481 // Separate projections were used for the exception path which
2482 // are normally removed by a late inline. If it wasn't inlined
2483 // then they will hang around and should just be replaced with
2484 // the original one.
2485 Node* proj = NULL;
2486 // Replace with just one
2487 for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
2488 Node *use = i.get();
2489 if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
2490 proj = use;
2491 break;
2492 }
2493 }
2494 assert(p != NULL, "must be found");
2495 p->subsume_by(proj);
2496 }
2497 }
2498 break;
2499 }
2500
2501 case Op_Phi:
2502 if (n->as_Phi()->bottom_type()->isa_narrowoop()) {
2503 // The EncodeP optimization may create Phi with the same edges
2504 // for all paths. It is not handled well by Register Allocator.
2505 Node* unique_in = n->in(1);
2506 assert(unique_in != NULL, "");
2507 uint cnt = n->req();
2508 for (uint i = 2; i < cnt; i++) {
2509 Node* m = n->in(i);
2510 assert(m != NULL, "");
2511 if (unique_in != m)
2512 unique_in = NULL;
2513 }
2514 if (unique_in != NULL) {
2515 n->subsume_by(unique_in);
2516 }
2517 }
2518 break;
2519
2520 #endif
2521
2522 case Op_ModI:
2523 if (UseDivMod) {
2524 // Check if a%b and a/b both exist
2525 Node* d = n->find_similar(Op_DivI);
2526 if (d) {
2527 // Replace them with a fused divmod if supported
2528 Compile* C = Compile::current();
2529 if (Matcher::has_match_rule(Op_DivModI)) {
2530 DivModINode* divmod = DivModINode::make(C, n);
2531 d->subsume_by(divmod->div_proj());
2532 n->subsume_by(divmod->mod_proj());
2533 } else {
2534 // replace a%b with a-((a/b)*b)
2535 Node* mult = new (C, 3) MulINode(d, d->in(2));
2536 Node* sub = new (C, 3) SubINode(d->in(1), mult);
2537 n->subsume_by( sub );
2538 }
2539 }
2540 }
2541 break;
2542
2543 case Op_ModL:
2544 if (UseDivMod) {
2545 // Check if a%b and a/b both exist
2546 Node* d = n->find_similar(Op_DivL);
2547 if (d) {
2548 // Replace them with a fused divmod if supported
2549 Compile* C = Compile::current();
2550 if (Matcher::has_match_rule(Op_DivModL)) {
2551 DivModLNode* divmod = DivModLNode::make(C, n);
2552 d->subsume_by(divmod->div_proj());
2553 n->subsume_by(divmod->mod_proj());
2554 } else {
2555 // replace a%b with a-((a/b)*b)
2556 Node* mult = new (C, 3) MulLNode(d, d->in(2));
2557 Node* sub = new (C, 3) SubLNode(d->in(1), mult);
2558 n->subsume_by( sub );
2559 }
2560 }
2561 }
2562 break;
2563
2564 case Op_Load16B:
2565 case Op_Load8B:
2566 case Op_Load4B:
2567 case Op_Load8S:
2568 case Op_Load4S:
2569 case Op_Load2S:
2570 case Op_Load8C:
2571 case Op_Load4C:
2572 case Op_Load2C:
2573 case Op_Load4I:
2574 case Op_Load2I:
2575 case Op_Load2L:
2576 case Op_Load4F:
2577 case Op_Load2F:
2578 case Op_Load2D:
2579 case Op_Store16B:
2580 case Op_Store8B:
2581 case Op_Store4B:
2582 case Op_Store8C:
2583 case Op_Store4C:
2584 case Op_Store2C:
2585 case Op_Store4I:
2586 case Op_Store2I:
2587 case Op_Store2L:
2588 case Op_Store4F:
2589 case Op_Store2F:
2590 case Op_Store2D:
2591 break;
2592
2593 case Op_PackB:
2594 case Op_PackS:
2595 case Op_PackC:
2596 case Op_PackI:
2597 case Op_PackF:
2598 case Op_PackL:
2599 case Op_PackD:
2600 if (n->req()-1 > 2) {
2601 // Replace many operand PackNodes with a binary tree for matching
2602 PackNode* p = (PackNode*) n;
2603 Node* btp = p->binaryTreePack(Compile::current(), 1, n->req());
2604 n->subsume_by(btp);
2605 }
2606 break;
2607 case Op_Loop:
2608 case Op_CountedLoop:
2609 if (n->as_Loop()->is_inner_loop()) {
2610 frc.inc_inner_loop_count();
2611 }
2612 break;
2613 case Op_LShiftI:
2614 case Op_RShiftI:
2615 case Op_URShiftI:
2616 case Op_LShiftL:
2617 case Op_RShiftL:
2618 case Op_URShiftL:
2619 if (Matcher::need_masked_shift_count) {
2620 // The cpu's shift instructions don't restrict the count to the
2621 // lower 5/6 bits. We need to do the masking ourselves.
2622 Node* in2 = n->in(2);
2623 juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
2624 const TypeInt* t = in2->find_int_type();
2625 if (t != NULL && t->is_con()) {
2626 juint shift = t->get_con();
2627 if (shift > mask) { // Unsigned cmp
2628 Compile* C = Compile::current();
2629 n->set_req(2, ConNode::make(C, TypeInt::make(shift & mask)));
2630 }
2631 } else {
2632 if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
2633 Compile* C = Compile::current();
2634 Node* shift = new (C, 3) AndINode(in2, ConNode::make(C, TypeInt::make(mask)));
2635 n->set_req(2, shift);
2636 }
2637 }
2638 if (in2->outcnt() == 0) { // Remove dead node
2639 in2->disconnect_inputs(NULL);
2640 }
2641 }
2642 break;
2643 default:
2644 assert( !n->is_Call(), "" );
2645 assert( !n->is_Mem(), "" );
2646 break;
2647 }
2648
2649 // Collect CFG split points
2650 if (n->is_MultiBranch())
2651 frc._tests.push(n);
2652 }
2653
2654 //------------------------------final_graph_reshaping_walk---------------------
2655 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
2656 // requires that the walk visits a node's inputs before visiting the node.
2657 static void final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
2658 ResourceArea *area = Thread::current()->resource_area();
2659 Unique_Node_List sfpt(area);
2660
2661 frc._visited.set(root->_idx); // first, mark node as visited
2662 uint cnt = root->req();
2663 Node *n = root;
2664 uint i = 0;
2665 while (true) {
2666 if (i < cnt) {
2667 // Place all non-visited non-null inputs onto stack
2668 Node* m = n->in(i);
2669 ++i;
2670 if (m != NULL && !frc._visited.test_set(m->_idx)) {
2671 if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL)
2672 sfpt.push(m);
2673 cnt = m->req();
2674 nstack.push(n, i); // put on stack parent and next input's index
2675 n = m;
2676 i = 0;
2677 }
2678 } else {
2679 // Now do post-visit work
2680 final_graph_reshaping_impl( n, frc );
2681 if (nstack.is_empty())
2682 break; // finished
2683 n = nstack.node(); // Get node from stack
2684 cnt = n->req();
2685 i = nstack.index();
2686 nstack.pop(); // Shift to the next node on stack
2687 }
2688 }
2689
2690 // Skip next transformation if compressed oops are not used.
2691 if (!UseCompressedOops || !Matcher::gen_narrow_oop_implicit_null_checks())
2692 return;
2693
2694 // Go over safepoints nodes to skip DecodeN nodes for debug edges.
2695 // It could be done for an uncommon traps or any safepoints/calls
2696 // if the DecodeN node is referenced only in a debug info.
2697 while (sfpt.size() > 0) {
2698 n = sfpt.pop();
2699 JVMState *jvms = n->as_SafePoint()->jvms();
2700 assert(jvms != NULL, "sanity");
2701 int start = jvms->debug_start();
2702 int end = n->req();
2703 bool is_uncommon = (n->is_CallStaticJava() &&
2704 n->as_CallStaticJava()->uncommon_trap_request() != 0);
2705 for (int j = start; j < end; j++) {
2706 Node* in = n->in(j);
2707 if (in->is_DecodeN()) {
2708 bool safe_to_skip = true;
2709 if (!is_uncommon ) {
2710 // Is it safe to skip?
2711 for (uint i = 0; i < in->outcnt(); i++) {
2712 Node* u = in->raw_out(i);
2713 if (!u->is_SafePoint() ||
2714 u->is_Call() && u->as_Call()->has_non_debug_use(n)) {
2715 safe_to_skip = false;
2716 }
2717 }
2718 }
2719 if (safe_to_skip) {
2720 n->set_req(j, in->in(1));
2721 }
2722 if (in->outcnt() == 0) {
2723 in->disconnect_inputs(NULL);
2724 }
2725 }
2726 }
2727 }
2728 }
2729
2730 //------------------------------final_graph_reshaping--------------------------
2731 // Final Graph Reshaping.
2732 //
2733 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
2734 // and not commoned up and forced early. Must come after regular
2735 // optimizations to avoid GVN undoing the cloning. Clone constant
2736 // inputs to Loop Phis; these will be split by the allocator anyways.
2737 // Remove Opaque nodes.
2738 // (2) Move last-uses by commutative operations to the left input to encourage
2739 // Intel update-in-place two-address operations and better register usage
2740 // on RISCs. Must come after regular optimizations to avoid GVN Ideal
2741 // calls canonicalizing them back.
2742 // (3) Count the number of double-precision FP ops, single-precision FP ops
2743 // and call sites. On Intel, we can get correct rounding either by
2744 // forcing singles to memory (requires extra stores and loads after each
2745 // FP bytecode) or we can set a rounding mode bit (requires setting and
2746 // clearing the mode bit around call sites). The mode bit is only used
2747 // if the relative frequency of single FP ops to calls is low enough.
2748 // This is a key transform for SPEC mpeg_audio.
2749 // (4) Detect infinite loops; blobs of code reachable from above but not
2750 // below. Several of the Code_Gen algorithms fail on such code shapes,
2751 // so we simply bail out. Happens a lot in ZKM.jar, but also happens
2752 // from time to time in other codes (such as -Xcomp finalizer loops, etc).
2753 // Detection is by looking for IfNodes where only 1 projection is
2754 // reachable from below or CatchNodes missing some targets.
2755 // (5) Assert for insane oop offsets in debug mode.
2756
2757 bool Compile::final_graph_reshaping() {
2758 // an infinite loop may have been eliminated by the optimizer,
2759 // in which case the graph will be empty.
2760 if (root()->req() == 1) {
2761 record_method_not_compilable("trivial infinite loop");
2762 return true;
2763 }
2764
2765 Final_Reshape_Counts frc;
2766
2767 // Visit everybody reachable!
2768 // Allocate stack of size C->unique()/2 to avoid frequent realloc
2769 Node_Stack nstack(unique() >> 1);
2770 final_graph_reshaping_walk(nstack, root(), frc);
2771
2772 // Check for unreachable (from below) code (i.e., infinite loops).
2773 for( uint i = 0; i < frc._tests.size(); i++ ) {
2774 MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
2775 // Get number of CFG targets.
2776 // Note that PCTables include exception targets after calls.
2777 uint required_outcnt = n->required_outcnt();
2778 if (n->outcnt() != required_outcnt) {
2779 // Check for a few special cases. Rethrow Nodes never take the
2780 // 'fall-thru' path, so expected kids is 1 less.
2781 if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
2782 if (n->in(0)->in(0)->is_Call()) {
2783 CallNode *call = n->in(0)->in(0)->as_Call();
2784 if (call->entry_point() == OptoRuntime::rethrow_stub()) {
2785 required_outcnt--; // Rethrow always has 1 less kid
2786 } else if (call->req() > TypeFunc::Parms &&
2787 call->is_CallDynamicJava()) {
2788 // Check for null receiver. In such case, the optimizer has
2789 // detected that the virtual call will always result in a null
2790 // pointer exception. The fall-through projection of this CatchNode
2791 // will not be populated.
2792 Node *arg0 = call->in(TypeFunc::Parms);
2793 if (arg0->is_Type() &&
2794 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
2795 required_outcnt--;
2796 }
2797 } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
2798 call->req() > TypeFunc::Parms+1 &&
2799 call->is_CallStaticJava()) {
2800 // Check for negative array length. In such case, the optimizer has
2801 // detected that the allocation attempt will always result in an
2802 // exception. There is no fall-through projection of this CatchNode .
2803 Node *arg1 = call->in(TypeFunc::Parms+1);
2804 if (arg1->is_Type() &&
2805 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
2806 required_outcnt--;
2807 }
2808 }
2809 }
2810 }
2811 // Recheck with a better notion of 'required_outcnt'
2812 if (n->outcnt() != required_outcnt) {
2813 record_method_not_compilable("malformed control flow");
2814 return true; // Not all targets reachable!
2815 }
2816 }
2817 // Check that I actually visited all kids. Unreached kids
2818 // must be infinite loops.
2819 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
2820 if (!frc._visited.test(n->fast_out(j)->_idx)) {
2821 record_method_not_compilable("infinite loop");
2822 return true; // Found unvisited kid; must be unreach
2823 }
2824 }
2825
2826 // If original bytecodes contained a mixture of floats and doubles
2827 // check if the optimizer has made it homogenous, item (3).
2828 if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
2829 frc.get_float_count() > 32 &&
2830 frc.get_double_count() == 0 &&
2831 (10 * frc.get_call_count() < frc.get_float_count()) ) {
2832 set_24_bit_selection_and_mode( false, true );
2833 }
2834
2835 set_java_calls(frc.get_java_call_count());
2836 set_inner_loops(frc.get_inner_loop_count());
2837
2838 // No infinite loops, no reason to bail out.
2839 return false;
2840 }
2841
2842 //-----------------------------too_many_traps----------------------------------
2843 // Report if there are too many traps at the current method and bci.
2844 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
2845 bool Compile::too_many_traps(ciMethod* method,
2846 int bci,
2847 Deoptimization::DeoptReason reason) {
2848 ciMethodData* md = method->method_data();
2849 if (md->is_empty()) {
2850 // Assume the trap has not occurred, or that it occurred only
2851 // because of a transient condition during start-up in the interpreter.
2852 return false;
2853 }
2854 if (md->has_trap_at(bci, reason) != 0) {
2855 // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
2856 // Also, if there are multiple reasons, or if there is no per-BCI record,
2857 // assume the worst.
2858 if (log())
2859 log()->elem("observe trap='%s' count='%d'",
2860 Deoptimization::trap_reason_name(reason),
2861 md->trap_count(reason));
2862 return true;
2863 } else {
2864 // Ignore method/bci and see if there have been too many globally.
2865 return too_many_traps(reason, md);
2866 }
2867 }
2868
2869 // Less-accurate variant which does not require a method and bci.
2870 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
2871 ciMethodData* logmd) {
2872 if (trap_count(reason) >= (uint)PerMethodTrapLimit) {
2873 // Too many traps globally.
2874 // Note that we use cumulative trap_count, not just md->trap_count.
2875 if (log()) {
2876 int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
2877 log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
2878 Deoptimization::trap_reason_name(reason),
2879 mcount, trap_count(reason));
2880 }
2881 return true;
2882 } else {
2883 // The coast is clear.
2884 return false;
2885 }
2886 }
2887
2888 //--------------------------too_many_recompiles--------------------------------
2889 // Report if there are too many recompiles at the current method and bci.
2890 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
2891 // Is not eager to return true, since this will cause the compiler to use
2892 // Action_none for a trap point, to avoid too many recompilations.
2893 bool Compile::too_many_recompiles(ciMethod* method,
2894 int bci,
2895 Deoptimization::DeoptReason reason) {
2896 ciMethodData* md = method->method_data();
2897 if (md->is_empty()) {
2898 // Assume the trap has not occurred, or that it occurred only
2899 // because of a transient condition during start-up in the interpreter.
2900 return false;
2901 }
2902 // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
2903 uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
2904 uint m_cutoff = (uint) PerMethodRecompilationCutoff / 2 + 1; // not zero
2905 Deoptimization::DeoptReason per_bc_reason
2906 = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
2907 if ((per_bc_reason == Deoptimization::Reason_none
2908 || md->has_trap_at(bci, reason) != 0)
2909 // The trap frequency measure we care about is the recompile count:
2910 && md->trap_recompiled_at(bci)
2911 && md->overflow_recompile_count() >= bc_cutoff) {
2912 // Do not emit a trap here if it has already caused recompilations.
2913 // Also, if there are multiple reasons, or if there is no per-BCI record,
2914 // assume the worst.
2915 if (log())
2916 log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
2917 Deoptimization::trap_reason_name(reason),
2918 md->trap_count(reason),
2919 md->overflow_recompile_count());
2920 return true;
2921 } else if (trap_count(reason) != 0
2922 && decompile_count() >= m_cutoff) {
2923 // Too many recompiles globally, and we have seen this sort of trap.
2924 // Use cumulative decompile_count, not just md->decompile_count.
2925 if (log())
2926 log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
2927 Deoptimization::trap_reason_name(reason),
2928 md->trap_count(reason), trap_count(reason),
2929 md->decompile_count(), decompile_count());
2930 return true;
2931 } else {
2932 // The coast is clear.
2933 return false;
2934 }
2935 }
2936
2937
2938 #ifndef PRODUCT
2939 //------------------------------verify_graph_edges---------------------------
2940 // Walk the Graph and verify that there is a one-to-one correspondence
2941 // between Use-Def edges and Def-Use edges in the graph.
2942 void Compile::verify_graph_edges(bool no_dead_code) {
2943 if (VerifyGraphEdges) {
2944 ResourceArea *area = Thread::current()->resource_area();
2945 Unique_Node_List visited(area);
2946 // Call recursive graph walk to check edges
2947 _root->verify_edges(visited);
2948 if (no_dead_code) {
2949 // Now make sure that no visited node is used by an unvisited node.
2950 bool dead_nodes = 0;
2951 Unique_Node_List checked(area);
2952 while (visited.size() > 0) {
2953 Node* n = visited.pop();
2954 checked.push(n);
2955 for (uint i = 0; i < n->outcnt(); i++) {
2956 Node* use = n->raw_out(i);
2957 if (checked.member(use)) continue; // already checked
2958 if (visited.member(use)) continue; // already in the graph
2959 if (use->is_Con()) continue; // a dead ConNode is OK
2960 // At this point, we have found a dead node which is DU-reachable.
2961 if (dead_nodes++ == 0)
2962 tty->print_cr("*** Dead nodes reachable via DU edges:");
2963 use->dump(2);
2964 tty->print_cr("---");
2965 checked.push(use); // No repeats; pretend it is now checked.
2966 }
2967 }
2968 assert(dead_nodes == 0, "using nodes must be reachable from root");
2969 }
2970 }
2971 }
2972 #endif
2973
2974 // The Compile object keeps track of failure reasons separately from the ciEnv.
2975 // This is required because there is not quite a 1-1 relation between the
2976 // ciEnv and its compilation task and the Compile object. Note that one
2977 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
2978 // to backtrack and retry without subsuming loads. Other than this backtracking
2979 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
2980 // by the logic in C2Compiler.
2981 void Compile::record_failure(const char* reason) {
2982 if (log() != NULL) {
2983 log()->elem("failure reason='%s' phase='compile'", reason);
2984 }
2985 if (_failure_reason == NULL) {
2986 // Record the first failure reason.
2987 _failure_reason = reason;
2988 }
2989 if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
2990 C->print_method(_failure_reason);
2991 }
2992 _root = NULL; // flush the graph, too
2993 }
2994
2995 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator, bool dolog)
2996 : TraceTime(NULL, accumulator, false NOT_PRODUCT( || TimeCompiler ), false)
2997 {
2998 if (dolog) {
2999 C = Compile::current();
3000 _log = C->log();
3001 } else {
3002 C = NULL;
3003 _log = NULL;
3004 }
3005 if (_log != NULL) {
3006 _log->begin_head("phase name='%s' nodes='%d'", name, C->unique());
3007 _log->stamp();
3008 _log->end_head();
3009 }
3010 }
3011
3012 Compile::TracePhase::~TracePhase() {
3013 if (_log != NULL) {
3014 _log->done("phase nodes='%d'", C->unique());
3015 }
3016 }
3017
3018 //=============================================================================
3019 // Two Constant's are equal when the type and the value are equal.
3020 bool Compile::Constant::operator==(const Constant& other) {
3021 if (type() != other.type() ) return false;
3022 if (can_be_reused() != other.can_be_reused()) return false;
3023 // For floating point values we compare the bit pattern.
3024 switch (type()) {
3025 case T_FLOAT: return (_value.i == other._value.i);
3026 case T_LONG:
3027 case T_DOUBLE: return (_value.j == other._value.j);
3028 case T_OBJECT:
3029 case T_ADDRESS: return (_value.l == other._value.l);
3030 case T_VOID: return (_value.l == other._value.l); // jump-table entries
3031 default: ShouldNotReachHere();
3032 }
3033 return false;
3034 }
3035
3036 // Emit constants grouped in the following order:
3037 static BasicType type_order[] = {
3038 T_FLOAT, // 32-bit
3039 T_OBJECT, // 32 or 64-bit
3040 T_ADDRESS, // 32 or 64-bit
3041 T_DOUBLE, // 64-bit
3042 T_LONG, // 64-bit
3043 T_VOID, // 32 or 64-bit (jump-tables are at the end of the constant table for code emission reasons)
3044 T_ILLEGAL
3045 };
3046
3047 static int type_to_size_in_bytes(BasicType t) {
3048 switch (t) {
3049 case T_LONG: return sizeof(jlong );
3050 case T_FLOAT: return sizeof(jfloat );
3051 case T_DOUBLE: return sizeof(jdouble);
3052 // We use T_VOID as marker for jump-table entries (labels) which
3053 // need an interal word relocation.
3054 case T_VOID:
3055 case T_ADDRESS:
3056 case T_OBJECT: return sizeof(jobject);
3057 }
3058
3059 ShouldNotReachHere();
3060 return -1;
3061 }
3062
3063 void Compile::ConstantTable::calculate_offsets_and_size() {
3064 int size = 0;
3065 for (int t = 0; type_order[t] != T_ILLEGAL; t++) {
3066 BasicType type = type_order[t];
3067
3068 for (int i = 0; i < _constants.length(); i++) {
3069 Constant con = _constants.at(i);
3070 if (con.type() != type) continue; // Skip other types.
3071
3072 // Align size for type.
3073 int typesize = type_to_size_in_bytes(con.type());
3074 size = align_size_up(size, typesize);
3075
3076 // Set offset.
3077 con.set_offset(size);
3078 _constants.at_put(i, con);
3079
3080 // Add type size.
3081 size = size + typesize;
3082 }
3083 }
3084
3085 // Align size up to the next section start (which is insts; see
3086 // CodeBuffer::align_at_start).
3087 assert(_size == -1, "already set?");
3088 _size = align_size_up(size, CodeEntryAlignment);
3089
3090 if (Matcher::constant_table_absolute_addressing) {
3091 set_table_base_offset(0); // No table base offset required
3092 } else {
3093 if (UseRDPCForConstantTableBase) {
3094 // table base offset is set in MachConstantBaseNode::emit
3095 } else {
3096 // When RDPC is not used, the table base is set into the middle of
3097 // the constant table.
3098 int half_size = _size / 2;
3099 assert(half_size * 2 == _size, "sanity");
3100 set_table_base_offset(-half_size);
3101 }
3102 }
3103 }
3104
3105 void Compile::ConstantTable::emit(CodeBuffer& cb) {
3106 MacroAssembler _masm(&cb);
3107 for (int t = 0; type_order[t] != T_ILLEGAL; t++) {
3108 BasicType type = type_order[t];
3109
3110 for (int i = 0; i < _constants.length(); i++) {
3111 Constant con = _constants.at(i);
3112 if (con.type() != type) continue; // Skip other types.
3113
3114 address constant_addr;
3115 switch (con.type()) {
3116 case T_LONG: constant_addr = _masm.long_constant( con.get_jlong() ); break;
3117 case T_FLOAT: constant_addr = _masm.float_constant( con.get_jfloat() ); break;
3118 case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
3119 case T_OBJECT: {
3120 jobject obj = con.get_jobject();
3121 int oop_index = _masm.oop_recorder()->find_index(obj);
3122 constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
3123 break;
3124 }
3125 case T_ADDRESS: {
3126 address addr = (address) con.get_jobject();
3127 constant_addr = _masm.address_constant(addr);
3128 break;
3129 }
3130 // We use T_VOID as marker for jump-table entries (labels) which
3131 // need an interal word relocation.
3132 case T_VOID: {
3133 // Write a dummy word. The real value is filled in later
3134 // in fill_jump_table_in_constant_table.
3135 address addr = (address) con.get_jobject();
3136 constant_addr = _masm.address_constant(addr);
3137 break;
3138 }
3139 default: ShouldNotReachHere();
3140 }
3141 assert(constant_addr != NULL, "consts section too small");
3142 assert((constant_addr - _masm.code()->consts()->start()) == con.offset(), err_msg("must be: %d == %d", constant_addr - _masm.code()->consts()->start(), con.offset()));
3143 }
3144 }
3145 }
3146
3147 int Compile::ConstantTable::find_offset(Constant& con) const {
3148 int idx = _constants.find(con);
3149 assert(idx != -1, "constant must be in constant table");
3150 int offset = _constants.at(idx).offset();
3151 assert(offset != -1, "constant table not emitted yet?");
3152 return offset;
3153 }
3154
3155 void Compile::ConstantTable::add(Constant& con) {
3156 if (con.can_be_reused()) {
3157 int idx = _constants.find(con);
3158 if (idx != -1 && _constants.at(idx).can_be_reused()) {
3159 return;
3160 }
3161 }
3162 (void) _constants.append(con);
3163 }
3164
3165 Compile::Constant Compile::ConstantTable::add(BasicType type, jvalue value) {
3166 Constant con(type, value);
3167 add(con);
3168 return con;
3169 }
3170
3171 Compile::Constant Compile::ConstantTable::add(MachOper* oper) {
3172 jvalue value;
3173 BasicType type = oper->type()->basic_type();
3174 switch (type) {
3175 case T_LONG: value.j = oper->constantL(); break;
3176 case T_FLOAT: value.f = oper->constantF(); break;
3177 case T_DOUBLE: value.d = oper->constantD(); break;
3178 case T_OBJECT:
3179 case T_ADDRESS: value.l = (jobject) oper->constant(); break;
3180 default: ShouldNotReachHere();
3181 }
3182 return add(type, value);
3183 }
3184
3185 Compile::Constant Compile::ConstantTable::allocate_jump_table(MachConstantNode* n) {
3186 jvalue value;
3187 // We can use the node pointer here to identify the right jump-table
3188 // as this method is called from Compile::Fill_buffer right before
3189 // the MachNodes are emitted and the jump-table is filled (means the
3190 // MachNode pointers do not change anymore).
3191 value.l = (jobject) n;
3192 Constant con(T_VOID, value, false); // Labels of a jump-table cannot be reused.
3193 for (uint i = 0; i < n->outcnt(); i++) {
3194 add(con);
3195 }
3196 return con;
3197 }
3198
3199 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
3200 // If called from Compile::scratch_emit_size do nothing.
3201 if (Compile::current()->in_scratch_emit_size()) return;
3202
3203 assert(labels.is_nonempty(), "must be");
3204 assert((uint) labels.length() == n->outcnt(), err_msg("must be equal: %d == %d", labels.length(), n->outcnt()));
3205
3206 // Since MachConstantNode::constant_offset() also contains
3207 // table_base_offset() we need to subtract the table_base_offset()
3208 // to get the plain offset into the constant table.
3209 int offset = n->constant_offset() - table_base_offset();
3210
3211 MacroAssembler _masm(&cb);
3212 address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
3213
3214 for (int i = 0; i < labels.length(); i++) {
3215 address* constant_addr = &jump_table_base[i];
3216 assert(*constant_addr == (address) n, "all jump-table entries must contain node pointer");
3217 *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
3218 cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
3219 }
3220 }