compile.cpp revision 3719:c3e799c37717
1/*
2 * Copyright (c) 1997, 2012, 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.
87MachConstantBaseNode* 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.
100int 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
135void 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
161CallGenerator* 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
193juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
194jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
195
196bool 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
233static 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
245void 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
266void 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
285Bundle* Compile::node_bundling(const Node *n) {
286  assert(valid_bundle_info(n), "oob");
287  return &_node_bundling_base[n->_idx];
288}
289
290bool Compile::valid_bundle_info(const Node *n) {
291  return (_node_bundling_limit > n->_idx);
292}
293
294
295void 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.
324void 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.
347void 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  // Remove useless macro and predicate opaq nodes
369  for (int i = C->macro_count()-1; i >= 0; i--) {
370    Node* n = C->macro_node(i);
371    if (!useful.member(n)) {
372      remove_macro_node(n);
373    }
374  }
375  debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
376}
377
378//------------------------------frame_size_in_words-----------------------------
379// frame_slots in units of words
380int Compile::frame_size_in_words() const {
381  // shift is 0 in LP32 and 1 in LP64
382  const int shift = (LogBytesPerWord - LogBytesPerInt);
383  int words = _frame_slots >> shift;
384  assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
385  return words;
386}
387
388// ============================================================================
389//------------------------------CompileWrapper---------------------------------
390class CompileWrapper : public StackObj {
391  Compile *const _compile;
392 public:
393  CompileWrapper(Compile* compile);
394
395  ~CompileWrapper();
396};
397
398CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
399  // the Compile* pointer is stored in the current ciEnv:
400  ciEnv* env = compile->env();
401  assert(env == ciEnv::current(), "must already be a ciEnv active");
402  assert(env->compiler_data() == NULL, "compile already active?");
403  env->set_compiler_data(compile);
404  assert(compile == Compile::current(), "sanity");
405
406  compile->set_type_dict(NULL);
407  compile->set_type_hwm(NULL);
408  compile->set_type_last_size(0);
409  compile->set_last_tf(NULL, NULL);
410  compile->set_indexSet_arena(NULL);
411  compile->set_indexSet_free_block_list(NULL);
412  compile->init_type_arena();
413  Type::Initialize(compile);
414  _compile->set_scratch_buffer_blob(NULL);
415  _compile->begin_method();
416}
417CompileWrapper::~CompileWrapper() {
418  _compile->end_method();
419  if (_compile->scratch_buffer_blob() != NULL)
420    BufferBlob::free(_compile->scratch_buffer_blob());
421  _compile->env()->set_compiler_data(NULL);
422}
423
424
425//----------------------------print_compile_messages---------------------------
426void Compile::print_compile_messages() {
427#ifndef PRODUCT
428  // Check if recompiling
429  if (_subsume_loads == false && PrintOpto) {
430    // Recompiling without allowing machine instructions to subsume loads
431    tty->print_cr("*********************************************************");
432    tty->print_cr("** Bailout: Recompile without subsuming loads          **");
433    tty->print_cr("*********************************************************");
434  }
435  if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
436    // Recompiling without escape analysis
437    tty->print_cr("*********************************************************");
438    tty->print_cr("** Bailout: Recompile without escape analysis          **");
439    tty->print_cr("*********************************************************");
440  }
441  if (env()->break_at_compile()) {
442    // Open the debugger when compiling this method.
443    tty->print("### Breaking when compiling: ");
444    method()->print_short_name();
445    tty->cr();
446    BREAKPOINT;
447  }
448
449  if( PrintOpto ) {
450    if (is_osr_compilation()) {
451      tty->print("[OSR]%3d", _compile_id);
452    } else {
453      tty->print("%3d", _compile_id);
454    }
455  }
456#endif
457}
458
459
460//-----------------------init_scratch_buffer_blob------------------------------
461// Construct a temporary BufferBlob and cache it for this compile.
462void Compile::init_scratch_buffer_blob(int const_size) {
463  // If there is already a scratch buffer blob allocated and the
464  // constant section is big enough, use it.  Otherwise free the
465  // current and allocate a new one.
466  BufferBlob* blob = scratch_buffer_blob();
467  if ((blob != NULL) && (const_size <= _scratch_const_size)) {
468    // Use the current blob.
469  } else {
470    if (blob != NULL) {
471      BufferBlob::free(blob);
472    }
473
474    ResourceMark rm;
475    _scratch_const_size = const_size;
476    int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
477    blob = BufferBlob::create("Compile::scratch_buffer", size);
478    // Record the buffer blob for next time.
479    set_scratch_buffer_blob(blob);
480    // Have we run out of code space?
481    if (scratch_buffer_blob() == NULL) {
482      // Let CompilerBroker disable further compilations.
483      record_failure("Not enough space for scratch buffer in CodeCache");
484      return;
485    }
486  }
487
488  // Initialize the relocation buffers
489  relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
490  set_scratch_locs_memory(locs_buf);
491}
492
493
494//-----------------------scratch_emit_size-------------------------------------
495// Helper function that computes size by emitting code
496uint Compile::scratch_emit_size(const Node* n) {
497  // Start scratch_emit_size section.
498  set_in_scratch_emit_size(true);
499
500  // Emit into a trash buffer and count bytes emitted.
501  // This is a pretty expensive way to compute a size,
502  // but it works well enough if seldom used.
503  // All common fixed-size instructions are given a size
504  // method by the AD file.
505  // Note that the scratch buffer blob and locs memory are
506  // allocated at the beginning of the compile task, and
507  // may be shared by several calls to scratch_emit_size.
508  // The allocation of the scratch buffer blob is particularly
509  // expensive, since it has to grab the code cache lock.
510  BufferBlob* blob = this->scratch_buffer_blob();
511  assert(blob != NULL, "Initialize BufferBlob at start");
512  assert(blob->size() > MAX_inst_size, "sanity");
513  relocInfo* locs_buf = scratch_locs_memory();
514  address blob_begin = blob->content_begin();
515  address blob_end   = (address)locs_buf;
516  assert(blob->content_contains(blob_end), "sanity");
517  CodeBuffer buf(blob_begin, blob_end - blob_begin);
518  buf.initialize_consts_size(_scratch_const_size);
519  buf.initialize_stubs_size(MAX_stubs_size);
520  assert(locs_buf != NULL, "sanity");
521  int lsize = MAX_locs_size / 3;
522  buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
523  buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
524  buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
525
526  // Do the emission.
527
528  Label fakeL; // Fake label for branch instructions.
529  Label*   saveL = NULL;
530  uint save_bnum = 0;
531  bool is_branch = n->is_MachBranch();
532  if (is_branch) {
533    MacroAssembler masm(&buf);
534    masm.bind(fakeL);
535    n->as_MachBranch()->save_label(&saveL, &save_bnum);
536    n->as_MachBranch()->label_set(&fakeL, 0);
537  }
538  n->emit(buf, this->regalloc());
539  if (is_branch) // Restore label.
540    n->as_MachBranch()->label_set(saveL, save_bnum);
541
542  // End scratch_emit_size section.
543  set_in_scratch_emit_size(false);
544
545  return buf.insts_size();
546}
547
548
549// ============================================================================
550//------------------------------Compile standard-------------------------------
551debug_only( int Compile::_debug_idx = 100000; )
552
553// Compile a method.  entry_bci is -1 for normal compilations and indicates
554// the continuation bci for on stack replacement.
555
556
557Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci, bool subsume_loads, bool do_escape_analysis )
558                : Phase(Compiler),
559                  _env(ci_env),
560                  _log(ci_env->log()),
561                  _compile_id(ci_env->compile_id()),
562                  _save_argument_registers(false),
563                  _stub_name(NULL),
564                  _stub_function(NULL),
565                  _stub_entry_point(NULL),
566                  _method(target),
567                  _entry_bci(osr_bci),
568                  _initial_gvn(NULL),
569                  _for_igvn(NULL),
570                  _warm_calls(NULL),
571                  _subsume_loads(subsume_loads),
572                  _do_escape_analysis(do_escape_analysis),
573                  _failure_reason(NULL),
574                  _code_buffer("Compile::Fill_buffer"),
575                  _orig_pc_slot(0),
576                  _orig_pc_slot_offset_in_bytes(0),
577                  _has_method_handle_invokes(false),
578                  _mach_constant_base_node(NULL),
579                  _node_bundling_limit(0),
580                  _node_bundling_base(NULL),
581                  _java_calls(0),
582                  _inner_loops(0),
583                  _scratch_const_size(-1),
584                  _in_scratch_emit_size(false),
585#ifndef PRODUCT
586                  _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
587                  _printer(IdealGraphPrinter::printer()),
588#endif
589                  _congraph(NULL) {
590  C = this;
591
592  CompileWrapper cw(this);
593#ifndef PRODUCT
594  if (TimeCompiler2) {
595    tty->print(" ");
596    target->holder()->name()->print();
597    tty->print(".");
598    target->print_short_name();
599    tty->print("  ");
600  }
601  TraceTime t1("Total compilation time", &_t_totalCompilation, TimeCompiler, TimeCompiler2);
602  TraceTime t2(NULL, &_t_methodCompilation, TimeCompiler, false);
603  bool print_opto_assembly = PrintOptoAssembly || _method->has_option("PrintOptoAssembly");
604  if (!print_opto_assembly) {
605    bool print_assembly = (PrintAssembly || _method->should_print_assembly());
606    if (print_assembly && !Disassembler::can_decode()) {
607      tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
608      print_opto_assembly = true;
609    }
610  }
611  set_print_assembly(print_opto_assembly);
612  set_parsed_irreducible_loop(false);
613#endif
614
615  if (ProfileTraps) {
616    // Make sure the method being compiled gets its own MDO,
617    // so we can at least track the decompile_count().
618    method()->ensure_method_data();
619  }
620
621  Init(::AliasLevel);
622
623
624  print_compile_messages();
625
626  if (UseOldInlining || PrintCompilation NOT_PRODUCT( || PrintOpto) )
627    _ilt = InlineTree::build_inline_tree_root();
628  else
629    _ilt = NULL;
630
631  // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
632  assert(num_alias_types() >= AliasIdxRaw, "");
633
634#define MINIMUM_NODE_HASH  1023
635  // Node list that Iterative GVN will start with
636  Unique_Node_List for_igvn(comp_arena());
637  set_for_igvn(&for_igvn);
638
639  // GVN that will be run immediately on new nodes
640  uint estimated_size = method()->code_size()*4+64;
641  estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
642  PhaseGVN gvn(node_arena(), estimated_size);
643  set_initial_gvn(&gvn);
644
645  { // Scope for timing the parser
646    TracePhase t3("parse", &_t_parser, true);
647
648    // Put top into the hash table ASAP.
649    initial_gvn()->transform_no_reclaim(top());
650
651    // Set up tf(), start(), and find a CallGenerator.
652    CallGenerator* cg = NULL;
653    if (is_osr_compilation()) {
654      const TypeTuple *domain = StartOSRNode::osr_domain();
655      const TypeTuple *range = TypeTuple::make_range(method()->signature());
656      init_tf(TypeFunc::make(domain, range));
657      StartNode* s = new (this) StartOSRNode(root(), domain);
658      initial_gvn()->set_type_bottom(s);
659      init_start(s);
660      cg = CallGenerator::for_osr(method(), entry_bci());
661    } else {
662      // Normal case.
663      init_tf(TypeFunc::make(method()));
664      StartNode* s = new (this) StartNode(root(), tf()->domain());
665      initial_gvn()->set_type_bottom(s);
666      init_start(s);
667      if (method()->intrinsic_id() == vmIntrinsics::_Reference_get && UseG1GC) {
668        // With java.lang.ref.reference.get() we must go through the
669        // intrinsic when G1 is enabled - even when get() is the root
670        // method of the compile - so that, if necessary, the value in
671        // the referent field of the reference object gets recorded by
672        // the pre-barrier code.
673        // Specifically, if G1 is enabled, the value in the referent
674        // field is recorded by the G1 SATB pre barrier. This will
675        // result in the referent being marked live and the reference
676        // object removed from the list of discovered references during
677        // reference processing.
678        cg = find_intrinsic(method(), false);
679      }
680      if (cg == NULL) {
681        float past_uses = method()->interpreter_invocation_count();
682        float expected_uses = past_uses;
683        cg = CallGenerator::for_inline(method(), expected_uses);
684      }
685    }
686    if (failing())  return;
687    if (cg == NULL) {
688      record_method_not_compilable_all_tiers("cannot parse method");
689      return;
690    }
691    JVMState* jvms = build_start_state(start(), tf());
692    if ((jvms = cg->generate(jvms)) == NULL) {
693      record_method_not_compilable("method parse failed");
694      return;
695    }
696    GraphKit kit(jvms);
697
698    if (!kit.stopped()) {
699      // Accept return values, and transfer control we know not where.
700      // This is done by a special, unique ReturnNode bound to root.
701      return_values(kit.jvms());
702    }
703
704    if (kit.has_exceptions()) {
705      // Any exceptions that escape from this call must be rethrown
706      // to whatever caller is dynamically above us on the stack.
707      // This is done by a special, unique RethrowNode bound to root.
708      rethrow_exceptions(kit.transfer_exceptions_into_jvms());
709    }
710
711    if (!failing() && has_stringbuilder()) {
712      {
713        // remove useless nodes to make the usage analysis simpler
714        ResourceMark rm;
715        PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
716      }
717
718      {
719        ResourceMark rm;
720        print_method("Before StringOpts", 3);
721        PhaseStringOpts pso(initial_gvn(), &for_igvn);
722        print_method("After StringOpts", 3);
723      }
724
725      // now inline anything that we skipped the first time around
726      while (_late_inlines.length() > 0) {
727        CallGenerator* cg = _late_inlines.pop();
728        cg->do_late_inline();
729        if (failing())  return;
730      }
731    }
732    assert(_late_inlines.length() == 0, "should have been processed");
733
734    print_method("Before RemoveUseless", 3);
735
736    // Remove clutter produced by parsing.
737    if (!failing()) {
738      ResourceMark rm;
739      PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
740    }
741  }
742
743  // Note:  Large methods are capped off in do_one_bytecode().
744  if (failing())  return;
745
746  // After parsing, node notes are no longer automagic.
747  // They must be propagated by register_new_node_with_optimizer(),
748  // clone(), or the like.
749  set_default_node_notes(NULL);
750
751  for (;;) {
752    int successes = Inline_Warm();
753    if (failing())  return;
754    if (successes == 0)  break;
755  }
756
757  // Drain the list.
758  Finish_Warm();
759#ifndef PRODUCT
760  if (_printer) {
761    _printer->print_inlining(this);
762  }
763#endif
764
765  if (failing())  return;
766  NOT_PRODUCT( verify_graph_edges(); )
767
768  // Now optimize
769  Optimize();
770  if (failing())  return;
771  NOT_PRODUCT( verify_graph_edges(); )
772
773#ifndef PRODUCT
774  if (PrintIdeal) {
775    ttyLocker ttyl;  // keep the following output all in one block
776    // This output goes directly to the tty, not the compiler log.
777    // To enable tools to match it up with the compilation activity,
778    // be sure to tag this tty output with the compile ID.
779    if (xtty != NULL) {
780      xtty->head("ideal compile_id='%d'%s", compile_id(),
781                 is_osr_compilation()    ? " compile_kind='osr'" :
782                 "");
783    }
784    root()->dump(9999);
785    if (xtty != NULL) {
786      xtty->tail("ideal");
787    }
788  }
789#endif
790
791  // Now that we know the size of all the monitors we can add a fixed slot
792  // for the original deopt pc.
793
794  _orig_pc_slot =  fixed_slots();
795  int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
796  set_fixed_slots(next_slot);
797
798  // Now generate code
799  Code_Gen();
800  if (failing())  return;
801
802  // Check if we want to skip execution of all compiled code.
803  {
804#ifndef PRODUCT
805    if (OptoNoExecute) {
806      record_method_not_compilable("+OptoNoExecute");  // Flag as failed
807      return;
808    }
809    TracePhase t2("install_code", &_t_registerMethod, TimeCompiler);
810#endif
811
812    if (is_osr_compilation()) {
813      _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
814      _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
815    } else {
816      _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
817      _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
818    }
819
820    env()->register_method(_method, _entry_bci,
821                           &_code_offsets,
822                           _orig_pc_slot_offset_in_bytes,
823                           code_buffer(),
824                           frame_size_in_words(), _oop_map_set,
825                           &_handler_table, &_inc_table,
826                           compiler,
827                           env()->comp_level(),
828                           has_unsafe_access(),
829                           SharedRuntime::is_wide_vector(max_vector_size())
830                           );
831
832    if (log() != NULL) // Print code cache state into compiler log
833      log()->code_cache_state();
834  }
835}
836
837//------------------------------Compile----------------------------------------
838// Compile a runtime stub
839Compile::Compile( ciEnv* ci_env,
840                  TypeFunc_generator generator,
841                  address stub_function,
842                  const char *stub_name,
843                  int is_fancy_jump,
844                  bool pass_tls,
845                  bool save_arg_registers,
846                  bool return_pc )
847  : Phase(Compiler),
848    _env(ci_env),
849    _log(ci_env->log()),
850    _compile_id(-1),
851    _save_argument_registers(save_arg_registers),
852    _method(NULL),
853    _stub_name(stub_name),
854    _stub_function(stub_function),
855    _stub_entry_point(NULL),
856    _entry_bci(InvocationEntryBci),
857    _initial_gvn(NULL),
858    _for_igvn(NULL),
859    _warm_calls(NULL),
860    _orig_pc_slot(0),
861    _orig_pc_slot_offset_in_bytes(0),
862    _subsume_loads(true),
863    _do_escape_analysis(false),
864    _failure_reason(NULL),
865    _code_buffer("Compile::Fill_buffer"),
866    _has_method_handle_invokes(false),
867    _mach_constant_base_node(NULL),
868    _node_bundling_limit(0),
869    _node_bundling_base(NULL),
870    _java_calls(0),
871    _inner_loops(0),
872#ifndef PRODUCT
873    _trace_opto_output(TraceOptoOutput),
874    _printer(NULL),
875#endif
876    _congraph(NULL) {
877  C = this;
878
879#ifndef PRODUCT
880  TraceTime t1(NULL, &_t_totalCompilation, TimeCompiler, false);
881  TraceTime t2(NULL, &_t_stubCompilation, TimeCompiler, false);
882  set_print_assembly(PrintFrameConverterAssembly);
883  set_parsed_irreducible_loop(false);
884#endif
885  CompileWrapper cw(this);
886  Init(/*AliasLevel=*/ 0);
887  init_tf((*generator)());
888
889  {
890    // The following is a dummy for the sake of GraphKit::gen_stub
891    Unique_Node_List for_igvn(comp_arena());
892    set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
893    PhaseGVN gvn(Thread::current()->resource_area(),255);
894    set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
895    gvn.transform_no_reclaim(top());
896
897    GraphKit kit;
898    kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
899  }
900
901  NOT_PRODUCT( verify_graph_edges(); )
902  Code_Gen();
903  if (failing())  return;
904
905
906  // Entry point will be accessed using compile->stub_entry_point();
907  if (code_buffer() == NULL) {
908    Matcher::soft_match_failure();
909  } else {
910    if (PrintAssembly && (WizardMode || Verbose))
911      tty->print_cr("### Stub::%s", stub_name);
912
913    if (!failing()) {
914      assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
915
916      // Make the NMethod
917      // For now we mark the frame as never safe for profile stackwalking
918      RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
919                                                      code_buffer(),
920                                                      CodeOffsets::frame_never_safe,
921                                                      // _code_offsets.value(CodeOffsets::Frame_Complete),
922                                                      frame_size_in_words(),
923                                                      _oop_map_set,
924                                                      save_arg_registers);
925      assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
926
927      _stub_entry_point = rs->entry_point();
928    }
929  }
930}
931
932//------------------------------Init-------------------------------------------
933// Prepare for a single compilation
934void Compile::Init(int aliaslevel) {
935  _unique  = 0;
936  _regalloc = NULL;
937
938  _tf      = NULL;  // filled in later
939  _top     = NULL;  // cached later
940  _matcher = NULL;  // filled in later
941  _cfg     = NULL;  // filled in later
942
943  set_24_bit_selection_and_mode(Use24BitFP, false);
944
945  _node_note_array = NULL;
946  _default_node_notes = NULL;
947
948  _immutable_memory = NULL; // filled in at first inquiry
949
950  // Globally visible Nodes
951  // First set TOP to NULL to give safe behavior during creation of RootNode
952  set_cached_top_node(NULL);
953  set_root(new (this) RootNode());
954  // Now that you have a Root to point to, create the real TOP
955  set_cached_top_node( new (this) ConNode(Type::TOP) );
956  set_recent_alloc(NULL, NULL);
957
958  // Create Debug Information Recorder to record scopes, oopmaps, etc.
959  env()->set_oop_recorder(new OopRecorder(env()->arena()));
960  env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
961  env()->set_dependencies(new Dependencies(env()));
962
963  _fixed_slots = 0;
964  set_has_split_ifs(false);
965  set_has_loops(has_method() && method()->has_loops()); // first approximation
966  set_has_stringbuilder(false);
967  _trap_can_recompile = false;  // no traps emitted yet
968  _major_progress = true; // start out assuming good things will happen
969  set_has_unsafe_access(false);
970  set_max_vector_size(0);
971  Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
972  set_decompile_count(0);
973
974  set_do_freq_based_layout(BlockLayoutByFrequency || method_has_option("BlockLayoutByFrequency"));
975  set_num_loop_opts(LoopOptsCount);
976  set_do_inlining(Inline);
977  set_max_inline_size(MaxInlineSize);
978  set_freq_inline_size(FreqInlineSize);
979  set_do_scheduling(OptoScheduling);
980  set_do_count_invocations(false);
981  set_do_method_data_update(false);
982
983  if (debug_info()->recording_non_safepoints()) {
984    set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
985                        (comp_arena(), 8, 0, NULL));
986    set_default_node_notes(Node_Notes::make(this));
987  }
988
989  // // -- Initialize types before each compile --
990  // // Update cached type information
991  // if( _method && _method->constants() )
992  //   Type::update_loaded_types(_method, _method->constants());
993
994  // Init alias_type map.
995  if (!_do_escape_analysis && aliaslevel == 3)
996    aliaslevel = 2;  // No unique types without escape analysis
997  _AliasLevel = aliaslevel;
998  const int grow_ats = 16;
999  _max_alias_types = grow_ats;
1000  _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
1001  AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
1002  Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
1003  {
1004    for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
1005  }
1006  // Initialize the first few types.
1007  _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
1008  _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1009  _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1010  _num_alias_types = AliasIdxRaw+1;
1011  // Zero out the alias type cache.
1012  Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1013  // A NULL adr_type hits in the cache right away.  Preload the right answer.
1014  probe_alias_cache(NULL)->_index = AliasIdxTop;
1015
1016  _intrinsics = NULL;
1017  _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1018  _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1019  register_library_intrinsics();
1020}
1021
1022//---------------------------init_start----------------------------------------
1023// Install the StartNode on this compile object.
1024void Compile::init_start(StartNode* s) {
1025  if (failing())
1026    return; // already failing
1027  assert(s == start(), "");
1028}
1029
1030StartNode* Compile::start() const {
1031  assert(!failing(), "");
1032  for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1033    Node* start = root()->fast_out(i);
1034    if( start->is_Start() )
1035      return start->as_Start();
1036  }
1037  ShouldNotReachHere();
1038  return NULL;
1039}
1040
1041//-------------------------------immutable_memory-------------------------------------
1042// Access immutable memory
1043Node* Compile::immutable_memory() {
1044  if (_immutable_memory != NULL) {
1045    return _immutable_memory;
1046  }
1047  StartNode* s = start();
1048  for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1049    Node *p = s->fast_out(i);
1050    if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1051      _immutable_memory = p;
1052      return _immutable_memory;
1053    }
1054  }
1055  ShouldNotReachHere();
1056  return NULL;
1057}
1058
1059//----------------------set_cached_top_node------------------------------------
1060// Install the cached top node, and make sure Node::is_top works correctly.
1061void Compile::set_cached_top_node(Node* tn) {
1062  if (tn != NULL)  verify_top(tn);
1063  Node* old_top = _top;
1064  _top = tn;
1065  // Calling Node::setup_is_top allows the nodes the chance to adjust
1066  // their _out arrays.
1067  if (_top != NULL)     _top->setup_is_top();
1068  if (old_top != NULL)  old_top->setup_is_top();
1069  assert(_top == NULL || top()->is_top(), "");
1070}
1071
1072#ifndef PRODUCT
1073void Compile::verify_top(Node* tn) const {
1074  if (tn != NULL) {
1075    assert(tn->is_Con(), "top node must be a constant");
1076    assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1077    assert(tn->in(0) != NULL, "must have live top node");
1078  }
1079}
1080#endif
1081
1082
1083///-------------------Managing Per-Node Debug & Profile Info-------------------
1084
1085void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1086  guarantee(arr != NULL, "");
1087  int num_blocks = arr->length();
1088  if (grow_by < num_blocks)  grow_by = num_blocks;
1089  int num_notes = grow_by * _node_notes_block_size;
1090  Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1091  Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1092  while (num_notes > 0) {
1093    arr->append(notes);
1094    notes     += _node_notes_block_size;
1095    num_notes -= _node_notes_block_size;
1096  }
1097  assert(num_notes == 0, "exact multiple, please");
1098}
1099
1100bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1101  if (source == NULL || dest == NULL)  return false;
1102
1103  if (dest->is_Con())
1104    return false;               // Do not push debug info onto constants.
1105
1106#ifdef ASSERT
1107  // Leave a bread crumb trail pointing to the original node:
1108  if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
1109    dest->set_debug_orig(source);
1110  }
1111#endif
1112
1113  if (node_note_array() == NULL)
1114    return false;               // Not collecting any notes now.
1115
1116  // This is a copy onto a pre-existing node, which may already have notes.
1117  // If both nodes have notes, do not overwrite any pre-existing notes.
1118  Node_Notes* source_notes = node_notes_at(source->_idx);
1119  if (source_notes == NULL || source_notes->is_clear())  return false;
1120  Node_Notes* dest_notes   = node_notes_at(dest->_idx);
1121  if (dest_notes == NULL || dest_notes->is_clear()) {
1122    return set_node_notes_at(dest->_idx, source_notes);
1123  }
1124
1125  Node_Notes merged_notes = (*source_notes);
1126  // The order of operations here ensures that dest notes will win...
1127  merged_notes.update_from(dest_notes);
1128  return set_node_notes_at(dest->_idx, &merged_notes);
1129}
1130
1131
1132//--------------------------allow_range_check_smearing-------------------------
1133// Gating condition for coalescing similar range checks.
1134// Sometimes we try 'speculatively' replacing a series of a range checks by a
1135// single covering check that is at least as strong as any of them.
1136// If the optimization succeeds, the simplified (strengthened) range check
1137// will always succeed.  If it fails, we will deopt, and then give up
1138// on the optimization.
1139bool Compile::allow_range_check_smearing() const {
1140  // If this method has already thrown a range-check,
1141  // assume it was because we already tried range smearing
1142  // and it failed.
1143  uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1144  return !already_trapped;
1145}
1146
1147
1148//------------------------------flatten_alias_type-----------------------------
1149const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1150  int offset = tj->offset();
1151  TypePtr::PTR ptr = tj->ptr();
1152
1153  // Known instance (scalarizable allocation) alias only with itself.
1154  bool is_known_inst = tj->isa_oopptr() != NULL &&
1155                       tj->is_oopptr()->is_known_instance();
1156
1157  // Process weird unsafe references.
1158  if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1159    assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
1160    assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1161    tj = TypeOopPtr::BOTTOM;
1162    ptr = tj->ptr();
1163    offset = tj->offset();
1164  }
1165
1166  // Array pointers need some flattening
1167  const TypeAryPtr *ta = tj->isa_aryptr();
1168  if( ta && is_known_inst ) {
1169    if ( offset != Type::OffsetBot &&
1170         offset > arrayOopDesc::length_offset_in_bytes() ) {
1171      offset = Type::OffsetBot; // Flatten constant access into array body only
1172      tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
1173    }
1174  } else if( ta && _AliasLevel >= 2 ) {
1175    // For arrays indexed by constant indices, we flatten the alias
1176    // space to include all of the array body.  Only the header, klass
1177    // and array length can be accessed un-aliased.
1178    if( offset != Type::OffsetBot ) {
1179      if( ta->const_oop() ) { // MethodData* or Method*
1180        offset = Type::OffsetBot;   // Flatten constant access into array body
1181        tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
1182      } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1183        // range is OK as-is.
1184        tj = ta = TypeAryPtr::RANGE;
1185      } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1186        tj = TypeInstPtr::KLASS; // all klass loads look alike
1187        ta = TypeAryPtr::RANGE; // generic ignored junk
1188        ptr = TypePtr::BotPTR;
1189      } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1190        tj = TypeInstPtr::MARK;
1191        ta = TypeAryPtr::RANGE; // generic ignored junk
1192        ptr = TypePtr::BotPTR;
1193      } else {                  // Random constant offset into array body
1194        offset = Type::OffsetBot;   // Flatten constant access into array body
1195        tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
1196      }
1197    }
1198    // Arrays of fixed size alias with arrays of unknown size.
1199    if (ta->size() != TypeInt::POS) {
1200      const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1201      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
1202    }
1203    // Arrays of known objects become arrays of unknown objects.
1204    if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1205      const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1206      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1207    }
1208    if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1209      const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1210      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1211    }
1212    // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1213    // cannot be distinguished by bytecode alone.
1214    if (ta->elem() == TypeInt::BOOL) {
1215      const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1216      ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1217      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
1218    }
1219    // During the 2nd round of IterGVN, NotNull castings are removed.
1220    // Make sure the Bottom and NotNull variants alias the same.
1221    // Also, make sure exact and non-exact variants alias the same.
1222    if( ptr == TypePtr::NotNull || ta->klass_is_exact() ) {
1223      tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
1224    }
1225  }
1226
1227  // Oop pointers need some flattening
1228  const TypeInstPtr *to = tj->isa_instptr();
1229  if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
1230    ciInstanceKlass *k = to->klass()->as_instance_klass();
1231    if( ptr == TypePtr::Constant ) {
1232      if (to->klass() != ciEnv::current()->Class_klass() ||
1233          offset < k->size_helper() * wordSize) {
1234        // No constant oop pointers (such as Strings); they alias with
1235        // unknown strings.
1236        assert(!is_known_inst, "not scalarizable allocation");
1237        tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1238      }
1239    } else if( is_known_inst ) {
1240      tj = to; // Keep NotNull and klass_is_exact for instance type
1241    } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1242      // During the 2nd round of IterGVN, NotNull castings are removed.
1243      // Make sure the Bottom and NotNull variants alias the same.
1244      // Also, make sure exact and non-exact variants alias the same.
1245      tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1246    }
1247    // Canonicalize the holder of this field
1248    if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1249      // First handle header references such as a LoadKlassNode, even if the
1250      // object's klass is unloaded at compile time (4965979).
1251      if (!is_known_inst) { // Do it only for non-instance types
1252        tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
1253      }
1254    } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
1255      // Static fields are in the space above the normal instance
1256      // fields in the java.lang.Class instance.
1257      if (to->klass() != ciEnv::current()->Class_klass()) {
1258        to = NULL;
1259        tj = TypeOopPtr::BOTTOM;
1260        offset = tj->offset();
1261      }
1262    } else {
1263      ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
1264      if (!k->equals(canonical_holder) || tj->offset() != offset) {
1265        if( is_known_inst ) {
1266          tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
1267        } else {
1268          tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
1269        }
1270      }
1271    }
1272  }
1273
1274  // Klass pointers to object array klasses need some flattening
1275  const TypeKlassPtr *tk = tj->isa_klassptr();
1276  if( tk ) {
1277    // If we are referencing a field within a Klass, we need
1278    // to assume the worst case of an Object.  Both exact and
1279    // inexact types must flatten to the same alias class so
1280    // use NotNull as the PTR.
1281    if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1282
1283      tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
1284                                   TypeKlassPtr::OBJECT->klass(),
1285                                   offset);
1286    }
1287
1288    ciKlass* klass = tk->klass();
1289    if( klass->is_obj_array_klass() ) {
1290      ciKlass* k = TypeAryPtr::OOPS->klass();
1291      if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
1292        k = TypeInstPtr::BOTTOM->klass();
1293      tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
1294    }
1295
1296    // Check for precise loads from the primary supertype array and force them
1297    // to the supertype cache alias index.  Check for generic array loads from
1298    // the primary supertype array and also force them to the supertype cache
1299    // alias index.  Since the same load can reach both, we need to merge
1300    // these 2 disparate memories into the same alias class.  Since the
1301    // primary supertype array is read-only, there's no chance of confusion
1302    // where we bypass an array load and an array store.
1303    int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
1304    if (offset == Type::OffsetBot ||
1305        (offset >= primary_supers_offset &&
1306         offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
1307        offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
1308      offset = in_bytes(Klass::secondary_super_cache_offset());
1309      tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
1310    }
1311  }
1312
1313  // Flatten all Raw pointers together.
1314  if (tj->base() == Type::RawPtr)
1315    tj = TypeRawPtr::BOTTOM;
1316
1317  if (tj->base() == Type::AnyPtr)
1318    tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
1319
1320  // Flatten all to bottom for now
1321  switch( _AliasLevel ) {
1322  case 0:
1323    tj = TypePtr::BOTTOM;
1324    break;
1325  case 1:                       // Flatten to: oop, static, field or array
1326    switch (tj->base()) {
1327    //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
1328    case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
1329    case Type::AryPtr:   // do not distinguish arrays at all
1330    case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
1331    case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
1332    case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
1333    default: ShouldNotReachHere();
1334    }
1335    break;
1336  case 2:                       // No collapsing at level 2; keep all splits
1337  case 3:                       // No collapsing at level 3; keep all splits
1338    break;
1339  default:
1340    Unimplemented();
1341  }
1342
1343  offset = tj->offset();
1344  assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1345
1346  assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1347          (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1348          (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1349          (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1350          (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1351          (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1352          (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr)  ,
1353          "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1354  assert( tj->ptr() != TypePtr::TopPTR &&
1355          tj->ptr() != TypePtr::AnyNull &&
1356          tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1357//    assert( tj->ptr() != TypePtr::Constant ||
1358//            tj->base() == Type::RawPtr ||
1359//            tj->base() == Type::KlassPtr, "No constant oop addresses" );
1360
1361  return tj;
1362}
1363
1364void Compile::AliasType::Init(int i, const TypePtr* at) {
1365  _index = i;
1366  _adr_type = at;
1367  _field = NULL;
1368  _is_rewritable = true; // default
1369  const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
1370  if (atoop != NULL && atoop->is_known_instance()) {
1371    const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1372    _general_index = Compile::current()->get_alias_index(gt);
1373  } else {
1374    _general_index = 0;
1375  }
1376}
1377
1378//---------------------------------print_on------------------------------------
1379#ifndef PRODUCT
1380void Compile::AliasType::print_on(outputStream* st) {
1381  if (index() < 10)
1382        st->print("@ <%d> ", index());
1383  else  st->print("@ <%d>",  index());
1384  st->print(is_rewritable() ? "   " : " RO");
1385  int offset = adr_type()->offset();
1386  if (offset == Type::OffsetBot)
1387        st->print(" +any");
1388  else  st->print(" +%-3d", offset);
1389  st->print(" in ");
1390  adr_type()->dump_on(st);
1391  const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1392  if (field() != NULL && tjp) {
1393    if (tjp->klass()  != field()->holder() ||
1394        tjp->offset() != field()->offset_in_bytes()) {
1395      st->print(" != ");
1396      field()->print();
1397      st->print(" ***");
1398    }
1399  }
1400}
1401
1402void print_alias_types() {
1403  Compile* C = Compile::current();
1404  tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1405  for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1406    C->alias_type(idx)->print_on(tty);
1407    tty->cr();
1408  }
1409}
1410#endif
1411
1412
1413//----------------------------probe_alias_cache--------------------------------
1414Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1415  intptr_t key = (intptr_t) adr_type;
1416  key ^= key >> logAliasCacheSize;
1417  return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1418}
1419
1420
1421//-----------------------------grow_alias_types--------------------------------
1422void Compile::grow_alias_types() {
1423  const int old_ats  = _max_alias_types; // how many before?
1424  const int new_ats  = old_ats;          // how many more?
1425  const int grow_ats = old_ats+new_ats;  // how many now?
1426  _max_alias_types = grow_ats;
1427  _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1428  AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1429  Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1430  for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
1431}
1432
1433
1434//--------------------------------find_alias_type------------------------------
1435Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1436  if (_AliasLevel == 0)
1437    return alias_type(AliasIdxBot);
1438
1439  AliasCacheEntry* ace = probe_alias_cache(adr_type);
1440  if (ace->_adr_type == adr_type) {
1441    return alias_type(ace->_index);
1442  }
1443
1444  // Handle special cases.
1445  if (adr_type == NULL)             return alias_type(AliasIdxTop);
1446  if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
1447
1448  // Do it the slow way.
1449  const TypePtr* flat = flatten_alias_type(adr_type);
1450
1451#ifdef ASSERT
1452  assert(flat == flatten_alias_type(flat), "idempotent");
1453  assert(flat != TypePtr::BOTTOM,     "cannot alias-analyze an untyped ptr");
1454  if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1455    const TypeOopPtr* foop = flat->is_oopptr();
1456    // Scalarizable allocations have exact klass always.
1457    bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1458    const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1459    assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type");
1460  }
1461  assert(flat == flatten_alias_type(flat), "exact bit doesn't matter");
1462#endif
1463
1464  int idx = AliasIdxTop;
1465  for (int i = 0; i < num_alias_types(); i++) {
1466    if (alias_type(i)->adr_type() == flat) {
1467      idx = i;
1468      break;
1469    }
1470  }
1471
1472  if (idx == AliasIdxTop) {
1473    if (no_create)  return NULL;
1474    // Grow the array if necessary.
1475    if (_num_alias_types == _max_alias_types)  grow_alias_types();
1476    // Add a new alias type.
1477    idx = _num_alias_types++;
1478    _alias_types[idx]->Init(idx, flat);
1479    if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
1480    if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
1481    if (flat->isa_instptr()) {
1482      if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
1483          && flat->is_instptr()->klass() == env()->Class_klass())
1484        alias_type(idx)->set_rewritable(false);
1485    }
1486    if (flat->isa_klassptr()) {
1487      if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
1488        alias_type(idx)->set_rewritable(false);
1489      if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
1490        alias_type(idx)->set_rewritable(false);
1491      if (flat->offset() == in_bytes(Klass::access_flags_offset()))
1492        alias_type(idx)->set_rewritable(false);
1493      if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
1494        alias_type(idx)->set_rewritable(false);
1495    }
1496    // %%% (We would like to finalize JavaThread::threadObj_offset(),
1497    // but the base pointer type is not distinctive enough to identify
1498    // references into JavaThread.)
1499
1500    // Check for final fields.
1501    const TypeInstPtr* tinst = flat->isa_instptr();
1502    if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1503      ciField* field;
1504      if (tinst->const_oop() != NULL &&
1505          tinst->klass() == ciEnv::current()->Class_klass() &&
1506          tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
1507        // static field
1508        ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1509        field = k->get_field_by_offset(tinst->offset(), true);
1510      } else {
1511        ciInstanceKlass *k = tinst->klass()->as_instance_klass();
1512        field = k->get_field_by_offset(tinst->offset(), false);
1513      }
1514      assert(field == NULL ||
1515             original_field == NULL ||
1516             (field->holder() == original_field->holder() &&
1517              field->offset() == original_field->offset() &&
1518              field->is_static() == original_field->is_static()), "wrong field?");
1519      // Set field() and is_rewritable() attributes.
1520      if (field != NULL)  alias_type(idx)->set_field(field);
1521    }
1522  }
1523
1524  // Fill the cache for next time.
1525  ace->_adr_type = adr_type;
1526  ace->_index    = idx;
1527  assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
1528
1529  // Might as well try to fill the cache for the flattened version, too.
1530  AliasCacheEntry* face = probe_alias_cache(flat);
1531  if (face->_adr_type == NULL) {
1532    face->_adr_type = flat;
1533    face->_index    = idx;
1534    assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1535  }
1536
1537  return alias_type(idx);
1538}
1539
1540
1541Compile::AliasType* Compile::alias_type(ciField* field) {
1542  const TypeOopPtr* t;
1543  if (field->is_static())
1544    t = TypeInstPtr::make(field->holder()->java_mirror());
1545  else
1546    t = TypeOopPtr::make_from_klass_raw(field->holder());
1547  AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1548  assert(field->is_final() == !atp->is_rewritable(), "must get the rewritable bits correct");
1549  return atp;
1550}
1551
1552
1553//------------------------------have_alias_type--------------------------------
1554bool Compile::have_alias_type(const TypePtr* adr_type) {
1555  AliasCacheEntry* ace = probe_alias_cache(adr_type);
1556  if (ace->_adr_type == adr_type) {
1557    return true;
1558  }
1559
1560  // Handle special cases.
1561  if (adr_type == NULL)             return true;
1562  if (adr_type == TypePtr::BOTTOM)  return true;
1563
1564  return find_alias_type(adr_type, true, NULL) != NULL;
1565}
1566
1567//-----------------------------must_alias--------------------------------------
1568// True if all values of the given address type are in the given alias category.
1569bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1570  if (alias_idx == AliasIdxBot)         return true;  // the universal category
1571  if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
1572  if (alias_idx == AliasIdxTop)         return false; // the empty category
1573  if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1574
1575  // the only remaining possible overlap is identity
1576  int adr_idx = get_alias_index(adr_type);
1577  assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1578  assert(adr_idx == alias_idx ||
1579         (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1580          && adr_type                       != TypeOopPtr::BOTTOM),
1581         "should not be testing for overlap with an unsafe pointer");
1582  return adr_idx == alias_idx;
1583}
1584
1585//------------------------------can_alias--------------------------------------
1586// True if any values of the given address type are in the given alias category.
1587bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1588  if (alias_idx == AliasIdxTop)         return false; // the empty category
1589  if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
1590  if (alias_idx == AliasIdxBot)         return true;  // the universal category
1591  if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
1592
1593  // the only remaining possible overlap is identity
1594  int adr_idx = get_alias_index(adr_type);
1595  assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1596  return adr_idx == alias_idx;
1597}
1598
1599
1600
1601//---------------------------pop_warm_call-------------------------------------
1602WarmCallInfo* Compile::pop_warm_call() {
1603  WarmCallInfo* wci = _warm_calls;
1604  if (wci != NULL)  _warm_calls = wci->remove_from(wci);
1605  return wci;
1606}
1607
1608//----------------------------Inline_Warm--------------------------------------
1609int Compile::Inline_Warm() {
1610  // If there is room, try to inline some more warm call sites.
1611  // %%% Do a graph index compaction pass when we think we're out of space?
1612  if (!InlineWarmCalls)  return 0;
1613
1614  int calls_made_hot = 0;
1615  int room_to_grow   = NodeCountInliningCutoff - unique();
1616  int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
1617  int amount_grown   = 0;
1618  WarmCallInfo* call;
1619  while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
1620    int est_size = (int)call->size();
1621    if (est_size > (room_to_grow - amount_grown)) {
1622      // This one won't fit anyway.  Get rid of it.
1623      call->make_cold();
1624      continue;
1625    }
1626    call->make_hot();
1627    calls_made_hot++;
1628    amount_grown   += est_size;
1629    amount_to_grow -= est_size;
1630  }
1631
1632  if (calls_made_hot > 0)  set_major_progress();
1633  return calls_made_hot;
1634}
1635
1636
1637//----------------------------Finish_Warm--------------------------------------
1638void Compile::Finish_Warm() {
1639  if (!InlineWarmCalls)  return;
1640  if (failing())  return;
1641  if (warm_calls() == NULL)  return;
1642
1643  // Clean up loose ends, if we are out of space for inlining.
1644  WarmCallInfo* call;
1645  while ((call = pop_warm_call()) != NULL) {
1646    call->make_cold();
1647  }
1648}
1649
1650//---------------------cleanup_loop_predicates-----------------------
1651// Remove the opaque nodes that protect the predicates so that all unused
1652// checks and uncommon_traps will be eliminated from the ideal graph
1653void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
1654  if (predicate_count()==0) return;
1655  for (int i = predicate_count(); i > 0; i--) {
1656    Node * n = predicate_opaque1_node(i-1);
1657    assert(n->Opcode() == Op_Opaque1, "must be");
1658    igvn.replace_node(n, n->in(1));
1659  }
1660  assert(predicate_count()==0, "should be clean!");
1661}
1662
1663//------------------------------Optimize---------------------------------------
1664// Given a graph, optimize it.
1665void Compile::Optimize() {
1666  TracePhase t1("optimizer", &_t_optimizer, true);
1667
1668#ifndef PRODUCT
1669  if (env()->break_at_compile()) {
1670    BREAKPOINT;
1671  }
1672
1673#endif
1674
1675  ResourceMark rm;
1676  int          loop_opts_cnt;
1677
1678  NOT_PRODUCT( verify_graph_edges(); )
1679
1680  print_method("After Parsing");
1681
1682 {
1683  // Iterative Global Value Numbering, including ideal transforms
1684  // Initialize IterGVN with types and values from parse-time GVN
1685  PhaseIterGVN igvn(initial_gvn());
1686  {
1687    NOT_PRODUCT( TracePhase t2("iterGVN", &_t_iterGVN, TimeCompiler); )
1688    igvn.optimize();
1689  }
1690
1691  print_method("Iter GVN 1", 2);
1692
1693  if (failing())  return;
1694
1695  // Perform escape analysis
1696  if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
1697    if (has_loops()) {
1698      // Cleanup graph (remove dead nodes).
1699      TracePhase t2("idealLoop", &_t_idealLoop, true);
1700      PhaseIdealLoop ideal_loop( igvn, false, true );
1701      if (major_progress()) print_method("PhaseIdealLoop before EA", 2);
1702      if (failing())  return;
1703    }
1704    ConnectionGraph::do_analysis(this, &igvn);
1705
1706    if (failing())  return;
1707
1708    // Optimize out fields loads from scalar replaceable allocations.
1709    igvn.optimize();
1710    print_method("Iter GVN after EA", 2);
1711
1712    if (failing())  return;
1713
1714    if (congraph() != NULL && macro_count() > 0) {
1715      NOT_PRODUCT( TracePhase t2("macroEliminate", &_t_macroEliminate, TimeCompiler); )
1716      PhaseMacroExpand mexp(igvn);
1717      mexp.eliminate_macro_nodes();
1718      igvn.set_delay_transform(false);
1719
1720      igvn.optimize();
1721      print_method("Iter GVN after eliminating allocations and locks", 2);
1722
1723      if (failing())  return;
1724    }
1725  }
1726
1727  // Loop transforms on the ideal graph.  Range Check Elimination,
1728  // peeling, unrolling, etc.
1729
1730  // Set loop opts counter
1731  loop_opts_cnt = num_loop_opts();
1732  if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
1733    {
1734      TracePhase t2("idealLoop", &_t_idealLoop, true);
1735      PhaseIdealLoop ideal_loop( igvn, true );
1736      loop_opts_cnt--;
1737      if (major_progress()) print_method("PhaseIdealLoop 1", 2);
1738      if (failing())  return;
1739    }
1740    // Loop opts pass if partial peeling occurred in previous pass
1741    if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
1742      TracePhase t3("idealLoop", &_t_idealLoop, true);
1743      PhaseIdealLoop ideal_loop( igvn, false );
1744      loop_opts_cnt--;
1745      if (major_progress()) print_method("PhaseIdealLoop 2", 2);
1746      if (failing())  return;
1747    }
1748    // Loop opts pass for loop-unrolling before CCP
1749    if(major_progress() && (loop_opts_cnt > 0)) {
1750      TracePhase t4("idealLoop", &_t_idealLoop, true);
1751      PhaseIdealLoop ideal_loop( igvn, false );
1752      loop_opts_cnt--;
1753      if (major_progress()) print_method("PhaseIdealLoop 3", 2);
1754    }
1755    if (!failing()) {
1756      // Verify that last round of loop opts produced a valid graph
1757      NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
1758      PhaseIdealLoop::verify(igvn);
1759    }
1760  }
1761  if (failing())  return;
1762
1763  // Conditional Constant Propagation;
1764  PhaseCCP ccp( &igvn );
1765  assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
1766  {
1767    TracePhase t2("ccp", &_t_ccp, true);
1768    ccp.do_transform();
1769  }
1770  print_method("PhaseCPP 1", 2);
1771
1772  assert( true, "Break here to ccp.dump_old2new_map()");
1773
1774  // Iterative Global Value Numbering, including ideal transforms
1775  {
1776    NOT_PRODUCT( TracePhase t2("iterGVN2", &_t_iterGVN2, TimeCompiler); )
1777    igvn = ccp;
1778    igvn.optimize();
1779  }
1780
1781  print_method("Iter GVN 2", 2);
1782
1783  if (failing())  return;
1784
1785  // Loop transforms on the ideal graph.  Range Check Elimination,
1786  // peeling, unrolling, etc.
1787  if(loop_opts_cnt > 0) {
1788    debug_only( int cnt = 0; );
1789    while(major_progress() && (loop_opts_cnt > 0)) {
1790      TracePhase t2("idealLoop", &_t_idealLoop, true);
1791      assert( cnt++ < 40, "infinite cycle in loop optimization" );
1792      PhaseIdealLoop ideal_loop( igvn, true);
1793      loop_opts_cnt--;
1794      if (major_progress()) print_method("PhaseIdealLoop iterations", 2);
1795      if (failing())  return;
1796    }
1797  }
1798
1799  {
1800    // Verify that all previous optimizations produced a valid graph
1801    // at least to this point, even if no loop optimizations were done.
1802    NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
1803    PhaseIdealLoop::verify(igvn);
1804  }
1805
1806  {
1807    NOT_PRODUCT( TracePhase t2("macroExpand", &_t_macroExpand, TimeCompiler); )
1808    PhaseMacroExpand  mex(igvn);
1809    if (mex.expand_macro_nodes()) {
1810      assert(failing(), "must bail out w/ explicit message");
1811      return;
1812    }
1813  }
1814
1815 } // (End scope of igvn; run destructor if necessary for asserts.)
1816
1817  // A method with only infinite loops has no edges entering loops from root
1818  {
1819    NOT_PRODUCT( TracePhase t2("graphReshape", &_t_graphReshaping, TimeCompiler); )
1820    if (final_graph_reshaping()) {
1821      assert(failing(), "must bail out w/ explicit message");
1822      return;
1823    }
1824  }
1825
1826  print_method("Optimize finished", 2);
1827}
1828
1829
1830//------------------------------Code_Gen---------------------------------------
1831// Given a graph, generate code for it
1832void Compile::Code_Gen() {
1833  if (failing())  return;
1834
1835  // Perform instruction selection.  You might think we could reclaim Matcher
1836  // memory PDQ, but actually the Matcher is used in generating spill code.
1837  // Internals of the Matcher (including some VectorSets) must remain live
1838  // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
1839  // set a bit in reclaimed memory.
1840
1841  // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
1842  // nodes.  Mapping is only valid at the root of each matched subtree.
1843  NOT_PRODUCT( verify_graph_edges(); )
1844
1845  Node_List proj_list;
1846  Matcher m(proj_list);
1847  _matcher = &m;
1848  {
1849    TracePhase t2("matcher", &_t_matcher, true);
1850    m.match();
1851  }
1852  // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
1853  // nodes.  Mapping is only valid at the root of each matched subtree.
1854  NOT_PRODUCT( verify_graph_edges(); )
1855
1856  // If you have too many nodes, or if matching has failed, bail out
1857  check_node_count(0, "out of nodes matching instructions");
1858  if (failing())  return;
1859
1860  // Build a proper-looking CFG
1861  PhaseCFG cfg(node_arena(), root(), m);
1862  _cfg = &cfg;
1863  {
1864    NOT_PRODUCT( TracePhase t2("scheduler", &_t_scheduler, TimeCompiler); )
1865    cfg.Dominators();
1866    if (failing())  return;
1867
1868    NOT_PRODUCT( verify_graph_edges(); )
1869
1870    cfg.Estimate_Block_Frequency();
1871    cfg.GlobalCodeMotion(m,unique(),proj_list);
1872    if (failing())  return;
1873
1874    print_method("Global code motion", 2);
1875
1876    NOT_PRODUCT( verify_graph_edges(); )
1877
1878    debug_only( cfg.verify(); )
1879  }
1880  NOT_PRODUCT( verify_graph_edges(); )
1881
1882  PhaseChaitin regalloc(unique(),cfg,m);
1883  _regalloc = &regalloc;
1884  {
1885    TracePhase t2("regalloc", &_t_registerAllocation, true);
1886    // Perform any platform dependent preallocation actions.  This is used,
1887    // for example, to avoid taking an implicit null pointer exception
1888    // using the frame pointer on win95.
1889    _regalloc->pd_preallocate_hook();
1890
1891    // Perform register allocation.  After Chaitin, use-def chains are
1892    // no longer accurate (at spill code) and so must be ignored.
1893    // Node->LRG->reg mappings are still accurate.
1894    _regalloc->Register_Allocate();
1895
1896    // Bail out if the allocator builds too many nodes
1897    if (failing())  return;
1898  }
1899
1900  // Prior to register allocation we kept empty basic blocks in case the
1901  // the allocator needed a place to spill.  After register allocation we
1902  // are not adding any new instructions.  If any basic block is empty, we
1903  // can now safely remove it.
1904  {
1905    NOT_PRODUCT( TracePhase t2("blockOrdering", &_t_blockOrdering, TimeCompiler); )
1906    cfg.remove_empty();
1907    if (do_freq_based_layout()) {
1908      PhaseBlockLayout layout(cfg);
1909    } else {
1910      cfg.set_loop_alignment();
1911    }
1912    cfg.fixup_flow();
1913  }
1914
1915  // Perform any platform dependent postallocation verifications.
1916  debug_only( _regalloc->pd_postallocate_verify_hook(); )
1917
1918  // Apply peephole optimizations
1919  if( OptoPeephole ) {
1920    NOT_PRODUCT( TracePhase t2("peephole", &_t_peephole, TimeCompiler); )
1921    PhasePeephole peep( _regalloc, cfg);
1922    peep.do_transform();
1923  }
1924
1925  // Convert Nodes to instruction bits in a buffer
1926  {
1927    // %%%% workspace merge brought two timers together for one job
1928    TracePhase t2a("output", &_t_output, true);
1929    NOT_PRODUCT( TraceTime t2b(NULL, &_t_codeGeneration, TimeCompiler, false); )
1930    Output();
1931  }
1932
1933  print_method("Final Code");
1934
1935  // He's dead, Jim.
1936  _cfg     = (PhaseCFG*)0xdeadbeef;
1937  _regalloc = (PhaseChaitin*)0xdeadbeef;
1938}
1939
1940
1941//------------------------------dump_asm---------------------------------------
1942// Dump formatted assembly
1943#ifndef PRODUCT
1944void Compile::dump_asm(int *pcs, uint pc_limit) {
1945  bool cut_short = false;
1946  tty->print_cr("#");
1947  tty->print("#  ");  _tf->dump();  tty->cr();
1948  tty->print_cr("#");
1949
1950  // For all blocks
1951  int pc = 0x0;                 // Program counter
1952  char starts_bundle = ' ';
1953  _regalloc->dump_frame();
1954
1955  Node *n = NULL;
1956  for( uint i=0; i<_cfg->_num_blocks; i++ ) {
1957    if (VMThread::should_terminate()) { cut_short = true; break; }
1958    Block *b = _cfg->_blocks[i];
1959    if (b->is_connector() && !Verbose) continue;
1960    n = b->_nodes[0];
1961    if (pcs && n->_idx < pc_limit)
1962      tty->print("%3.3x   ", pcs[n->_idx]);
1963    else
1964      tty->print("      ");
1965    b->dump_head( &_cfg->_bbs );
1966    if (b->is_connector()) {
1967      tty->print_cr("        # Empty connector block");
1968    } else if (b->num_preds() == 2 && b->pred(1)->is_CatchProj() && b->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
1969      tty->print_cr("        # Block is sole successor of call");
1970    }
1971
1972    // For all instructions
1973    Node *delay = NULL;
1974    for( uint j = 0; j<b->_nodes.size(); j++ ) {
1975      if (VMThread::should_terminate()) { cut_short = true; break; }
1976      n = b->_nodes[j];
1977      if (valid_bundle_info(n)) {
1978        Bundle *bundle = node_bundling(n);
1979        if (bundle->used_in_unconditional_delay()) {
1980          delay = n;
1981          continue;
1982        }
1983        if (bundle->starts_bundle())
1984          starts_bundle = '+';
1985      }
1986
1987      if (WizardMode) n->dump();
1988
1989      if( !n->is_Region() &&    // Dont print in the Assembly
1990          !n->is_Phi() &&       // a few noisely useless nodes
1991          !n->is_Proj() &&
1992          !n->is_MachTemp() &&
1993          !n->is_SafePointScalarObject() &&
1994          !n->is_Catch() &&     // Would be nice to print exception table targets
1995          !n->is_MergeMem() &&  // Not very interesting
1996          !n->is_top() &&       // Debug info table constants
1997          !(n->is_Con() && !n->is_Mach())// Debug info table constants
1998          ) {
1999        if (pcs && n->_idx < pc_limit)
2000          tty->print("%3.3x", pcs[n->_idx]);
2001        else
2002          tty->print("   ");
2003        tty->print(" %c ", starts_bundle);
2004        starts_bundle = ' ';
2005        tty->print("\t");
2006        n->format(_regalloc, tty);
2007        tty->cr();
2008      }
2009
2010      // If we have an instruction with a delay slot, and have seen a delay,
2011      // then back up and print it
2012      if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
2013        assert(delay != NULL, "no unconditional delay instruction");
2014        if (WizardMode) delay->dump();
2015
2016        if (node_bundling(delay)->starts_bundle())
2017          starts_bundle = '+';
2018        if (pcs && n->_idx < pc_limit)
2019          tty->print("%3.3x", pcs[n->_idx]);
2020        else
2021          tty->print("   ");
2022        tty->print(" %c ", starts_bundle);
2023        starts_bundle = ' ';
2024        tty->print("\t");
2025        delay->format(_regalloc, tty);
2026        tty->print_cr("");
2027        delay = NULL;
2028      }
2029
2030      // Dump the exception table as well
2031      if( n->is_Catch() && (Verbose || WizardMode) ) {
2032        // Print the exception table for this offset
2033        _handler_table.print_subtable_for(pc);
2034      }
2035    }
2036
2037    if (pcs && n->_idx < pc_limit)
2038      tty->print_cr("%3.3x", pcs[n->_idx]);
2039    else
2040      tty->print_cr("");
2041
2042    assert(cut_short || delay == NULL, "no unconditional delay branch");
2043
2044  } // End of per-block dump
2045  tty->print_cr("");
2046
2047  if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
2048}
2049#endif
2050
2051//------------------------------Final_Reshape_Counts---------------------------
2052// This class defines counters to help identify when a method
2053// may/must be executed using hardware with only 24-bit precision.
2054struct Final_Reshape_Counts : public StackObj {
2055  int  _call_count;             // count non-inlined 'common' calls
2056  int  _float_count;            // count float ops requiring 24-bit precision
2057  int  _double_count;           // count double ops requiring more precision
2058  int  _java_call_count;        // count non-inlined 'java' calls
2059  int  _inner_loop_count;       // count loops which need alignment
2060  VectorSet _visited;           // Visitation flags
2061  Node_List _tests;             // Set of IfNodes & PCTableNodes
2062
2063  Final_Reshape_Counts() :
2064    _call_count(0), _float_count(0), _double_count(0),
2065    _java_call_count(0), _inner_loop_count(0),
2066    _visited( Thread::current()->resource_area() ) { }
2067
2068  void inc_call_count  () { _call_count  ++; }
2069  void inc_float_count () { _float_count ++; }
2070  void inc_double_count() { _double_count++; }
2071  void inc_java_call_count() { _java_call_count++; }
2072  void inc_inner_loop_count() { _inner_loop_count++; }
2073
2074  int  get_call_count  () const { return _call_count  ; }
2075  int  get_float_count () const { return _float_count ; }
2076  int  get_double_count() const { return _double_count; }
2077  int  get_java_call_count() const { return _java_call_count; }
2078  int  get_inner_loop_count() const { return _inner_loop_count; }
2079};
2080
2081static bool oop_offset_is_sane(const TypeInstPtr* tp) {
2082  ciInstanceKlass *k = tp->klass()->as_instance_klass();
2083  // Make sure the offset goes inside the instance layout.
2084  return k->contains_field_offset(tp->offset());
2085  // Note that OffsetBot and OffsetTop are very negative.
2086}
2087
2088// Eliminate trivially redundant StoreCMs and accumulate their
2089// precedence edges.
2090static void eliminate_redundant_card_marks(Node* n) {
2091  assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
2092  if (n->in(MemNode::Address)->outcnt() > 1) {
2093    // There are multiple users of the same address so it might be
2094    // possible to eliminate some of the StoreCMs
2095    Node* mem = n->in(MemNode::Memory);
2096    Node* adr = n->in(MemNode::Address);
2097    Node* val = n->in(MemNode::ValueIn);
2098    Node* prev = n;
2099    bool done = false;
2100    // Walk the chain of StoreCMs eliminating ones that match.  As
2101    // long as it's a chain of single users then the optimization is
2102    // safe.  Eliminating partially redundant StoreCMs would require
2103    // cloning copies down the other paths.
2104    while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
2105      if (adr == mem->in(MemNode::Address) &&
2106          val == mem->in(MemNode::ValueIn)) {
2107        // redundant StoreCM
2108        if (mem->req() > MemNode::OopStore) {
2109          // Hasn't been processed by this code yet.
2110          n->add_prec(mem->in(MemNode::OopStore));
2111        } else {
2112          // Already converted to precedence edge
2113          for (uint i = mem->req(); i < mem->len(); i++) {
2114            // Accumulate any precedence edges
2115            if (mem->in(i) != NULL) {
2116              n->add_prec(mem->in(i));
2117            }
2118          }
2119          // Everything above this point has been processed.
2120          done = true;
2121        }
2122        // Eliminate the previous StoreCM
2123        prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
2124        assert(mem->outcnt() == 0, "should be dead");
2125        mem->disconnect_inputs(NULL);
2126      } else {
2127        prev = mem;
2128      }
2129      mem = prev->in(MemNode::Memory);
2130    }
2131  }
2132}
2133
2134//------------------------------final_graph_reshaping_impl----------------------
2135// Implement items 1-5 from final_graph_reshaping below.
2136static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
2137
2138  if ( n->outcnt() == 0 ) return; // dead node
2139  uint nop = n->Opcode();
2140
2141  // Check for 2-input instruction with "last use" on right input.
2142  // Swap to left input.  Implements item (2).
2143  if( n->req() == 3 &&          // two-input instruction
2144      n->in(1)->outcnt() > 1 && // left use is NOT a last use
2145      (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
2146      n->in(2)->outcnt() == 1 &&// right use IS a last use
2147      !n->in(2)->is_Con() ) {   // right use is not a constant
2148    // Check for commutative opcode
2149    switch( nop ) {
2150    case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
2151    case Op_MaxI:  case Op_MinI:
2152    case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
2153    case Op_AndL:  case Op_XorL:  case Op_OrL:
2154    case Op_AndI:  case Op_XorI:  case Op_OrI: {
2155      // Move "last use" input to left by swapping inputs
2156      n->swap_edges(1, 2);
2157      break;
2158    }
2159    default:
2160      break;
2161    }
2162  }
2163
2164#ifdef ASSERT
2165  if( n->is_Mem() ) {
2166    Compile* C = Compile::current();
2167    int alias_idx = C->get_alias_index(n->as_Mem()->adr_type());
2168    assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
2169            // oop will be recorded in oop map if load crosses safepoint
2170            n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
2171                             LoadNode::is_immutable_value(n->in(MemNode::Address))),
2172            "raw memory operations should have control edge");
2173  }
2174#endif
2175  // Count FPU ops and common calls, implements item (3)
2176  switch( nop ) {
2177  // Count all float operations that may use FPU
2178  case Op_AddF:
2179  case Op_SubF:
2180  case Op_MulF:
2181  case Op_DivF:
2182  case Op_NegF:
2183  case Op_ModF:
2184  case Op_ConvI2F:
2185  case Op_ConF:
2186  case Op_CmpF:
2187  case Op_CmpF3:
2188  // case Op_ConvL2F: // longs are split into 32-bit halves
2189    frc.inc_float_count();
2190    break;
2191
2192  case Op_ConvF2D:
2193  case Op_ConvD2F:
2194    frc.inc_float_count();
2195    frc.inc_double_count();
2196    break;
2197
2198  // Count all double operations that may use FPU
2199  case Op_AddD:
2200  case Op_SubD:
2201  case Op_MulD:
2202  case Op_DivD:
2203  case Op_NegD:
2204  case Op_ModD:
2205  case Op_ConvI2D:
2206  case Op_ConvD2I:
2207  // case Op_ConvL2D: // handled by leaf call
2208  // case Op_ConvD2L: // handled by leaf call
2209  case Op_ConD:
2210  case Op_CmpD:
2211  case Op_CmpD3:
2212    frc.inc_double_count();
2213    break;
2214  case Op_Opaque1:              // Remove Opaque Nodes before matching
2215  case Op_Opaque2:              // Remove Opaque Nodes before matching
2216    n->subsume_by(n->in(1));
2217    break;
2218  case Op_CallStaticJava:
2219  case Op_CallJava:
2220  case Op_CallDynamicJava:
2221    frc.inc_java_call_count(); // Count java call site;
2222  case Op_CallRuntime:
2223  case Op_CallLeaf:
2224  case Op_CallLeafNoFP: {
2225    assert( n->is_Call(), "" );
2226    CallNode *call = n->as_Call();
2227    // Count call sites where the FP mode bit would have to be flipped.
2228    // Do not count uncommon runtime calls:
2229    // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
2230    // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
2231    if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
2232      frc.inc_call_count();   // Count the call site
2233    } else {                  // See if uncommon argument is shared
2234      Node *n = call->in(TypeFunc::Parms);
2235      int nop = n->Opcode();
2236      // Clone shared simple arguments to uncommon calls, item (1).
2237      if( n->outcnt() > 1 &&
2238          !n->is_Proj() &&
2239          nop != Op_CreateEx &&
2240          nop != Op_CheckCastPP &&
2241          nop != Op_DecodeN &&
2242          !n->is_Mem() ) {
2243        Node *x = n->clone();
2244        call->set_req( TypeFunc::Parms, x );
2245      }
2246    }
2247    break;
2248  }
2249
2250  case Op_StoreD:
2251  case Op_LoadD:
2252  case Op_LoadD_unaligned:
2253    frc.inc_double_count();
2254    goto handle_mem;
2255  case Op_StoreF:
2256  case Op_LoadF:
2257    frc.inc_float_count();
2258    goto handle_mem;
2259
2260  case Op_StoreCM:
2261    {
2262      // Convert OopStore dependence into precedence edge
2263      Node* prec = n->in(MemNode::OopStore);
2264      n->del_req(MemNode::OopStore);
2265      n->add_prec(prec);
2266      eliminate_redundant_card_marks(n);
2267    }
2268
2269    // fall through
2270
2271  case Op_StoreB:
2272  case Op_StoreC:
2273  case Op_StorePConditional:
2274  case Op_StoreI:
2275  case Op_StoreL:
2276  case Op_StoreIConditional:
2277  case Op_StoreLConditional:
2278  case Op_CompareAndSwapI:
2279  case Op_CompareAndSwapL:
2280  case Op_CompareAndSwapP:
2281  case Op_CompareAndSwapN:
2282  case Op_GetAndAddI:
2283  case Op_GetAndAddL:
2284  case Op_GetAndSetI:
2285  case Op_GetAndSetL:
2286  case Op_GetAndSetP:
2287  case Op_GetAndSetN:
2288  case Op_StoreP:
2289  case Op_StoreN:
2290  case Op_LoadB:
2291  case Op_LoadUB:
2292  case Op_LoadUS:
2293  case Op_LoadI:
2294  case Op_LoadUI2L:
2295  case Op_LoadKlass:
2296  case Op_LoadNKlass:
2297  case Op_LoadL:
2298  case Op_LoadL_unaligned:
2299  case Op_LoadPLocked:
2300  case Op_LoadP:
2301  case Op_LoadN:
2302  case Op_LoadRange:
2303  case Op_LoadS: {
2304  handle_mem:
2305#ifdef ASSERT
2306    if( VerifyOptoOopOffsets ) {
2307      assert( n->is_Mem(), "" );
2308      MemNode *mem  = (MemNode*)n;
2309      // Check to see if address types have grounded out somehow.
2310      const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
2311      assert( !tp || oop_offset_is_sane(tp), "" );
2312    }
2313#endif
2314    break;
2315  }
2316
2317  case Op_AddP: {               // Assert sane base pointers
2318    Node *addp = n->in(AddPNode::Address);
2319    assert( !addp->is_AddP() ||
2320            addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
2321            addp->in(AddPNode::Base) == n->in(AddPNode::Base),
2322            "Base pointers must match" );
2323#ifdef _LP64
2324    if (UseCompressedOops &&
2325        addp->Opcode() == Op_ConP &&
2326        addp == n->in(AddPNode::Base) &&
2327        n->in(AddPNode::Offset)->is_Con()) {
2328      // Use addressing with narrow klass to load with offset on x86.
2329      // On sparc loading 32-bits constant and decoding it have less
2330      // instructions (4) then load 64-bits constant (7).
2331      // Do this transformation here since IGVN will convert ConN back to ConP.
2332      const Type* t = addp->bottom_type();
2333      if (t->isa_oopptr()) {
2334        Node* nn = NULL;
2335
2336        // Look for existing ConN node of the same exact type.
2337        Compile* C = Compile::current();
2338        Node* r  = C->root();
2339        uint cnt = r->outcnt();
2340        for (uint i = 0; i < cnt; i++) {
2341          Node* m = r->raw_out(i);
2342          if (m!= NULL && m->Opcode() == Op_ConN &&
2343              m->bottom_type()->make_ptr() == t) {
2344            nn = m;
2345            break;
2346          }
2347        }
2348        if (nn != NULL) {
2349          // Decode a narrow oop to match address
2350          // [R12 + narrow_oop_reg<<3 + offset]
2351          nn = new (C) DecodeNNode(nn, t);
2352          n->set_req(AddPNode::Base, nn);
2353          n->set_req(AddPNode::Address, nn);
2354          if (addp->outcnt() == 0) {
2355            addp->disconnect_inputs(NULL);
2356          }
2357        }
2358      }
2359    }
2360#endif
2361    break;
2362  }
2363
2364#ifdef _LP64
2365  case Op_CastPP:
2366    if (n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
2367      Compile* C = Compile::current();
2368      Node* in1 = n->in(1);
2369      const Type* t = n->bottom_type();
2370      Node* new_in1 = in1->clone();
2371      new_in1->as_DecodeN()->set_type(t);
2372
2373      if (!Matcher::narrow_oop_use_complex_address()) {
2374        //
2375        // x86, ARM and friends can handle 2 adds in addressing mode
2376        // and Matcher can fold a DecodeN node into address by using
2377        // a narrow oop directly and do implicit NULL check in address:
2378        //
2379        // [R12 + narrow_oop_reg<<3 + offset]
2380        // NullCheck narrow_oop_reg
2381        //
2382        // On other platforms (Sparc) we have to keep new DecodeN node and
2383        // use it to do implicit NULL check in address:
2384        //
2385        // decode_not_null narrow_oop_reg, base_reg
2386        // [base_reg + offset]
2387        // NullCheck base_reg
2388        //
2389        // Pin the new DecodeN node to non-null path on these platform (Sparc)
2390        // to keep the information to which NULL check the new DecodeN node
2391        // corresponds to use it as value in implicit_null_check().
2392        //
2393        new_in1->set_req(0, n->in(0));
2394      }
2395
2396      n->subsume_by(new_in1);
2397      if (in1->outcnt() == 0) {
2398        in1->disconnect_inputs(NULL);
2399      }
2400    }
2401    break;
2402
2403  case Op_CmpP:
2404    // Do this transformation here to preserve CmpPNode::sub() and
2405    // other TypePtr related Ideal optimizations (for example, ptr nullness).
2406    if (n->in(1)->is_DecodeN() || n->in(2)->is_DecodeN()) {
2407      Node* in1 = n->in(1);
2408      Node* in2 = n->in(2);
2409      if (!in1->is_DecodeN()) {
2410        in2 = in1;
2411        in1 = n->in(2);
2412      }
2413      assert(in1->is_DecodeN(), "sanity");
2414
2415      Compile* C = Compile::current();
2416      Node* new_in2 = NULL;
2417      if (in2->is_DecodeN()) {
2418        new_in2 = in2->in(1);
2419      } else if (in2->Opcode() == Op_ConP) {
2420        const Type* t = in2->bottom_type();
2421        if (t == TypePtr::NULL_PTR) {
2422          // Don't convert CmpP null check into CmpN if compressed
2423          // oops implicit null check is not generated.
2424          // This will allow to generate normal oop implicit null check.
2425          if (Matcher::gen_narrow_oop_implicit_null_checks())
2426            new_in2 = ConNode::make(C, TypeNarrowOop::NULL_PTR);
2427          //
2428          // This transformation together with CastPP transformation above
2429          // will generated code for implicit NULL checks for compressed oops.
2430          //
2431          // The original code after Optimize()
2432          //
2433          //    LoadN memory, narrow_oop_reg
2434          //    decode narrow_oop_reg, base_reg
2435          //    CmpP base_reg, NULL
2436          //    CastPP base_reg // NotNull
2437          //    Load [base_reg + offset], val_reg
2438          //
2439          // after these transformations will be
2440          //
2441          //    LoadN memory, narrow_oop_reg
2442          //    CmpN narrow_oop_reg, NULL
2443          //    decode_not_null narrow_oop_reg, base_reg
2444          //    Load [base_reg + offset], val_reg
2445          //
2446          // and the uncommon path (== NULL) will use narrow_oop_reg directly
2447          // since narrow oops can be used in debug info now (see the code in
2448          // final_graph_reshaping_walk()).
2449          //
2450          // At the end the code will be matched to
2451          // on x86:
2452          //
2453          //    Load_narrow_oop memory, narrow_oop_reg
2454          //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
2455          //    NullCheck narrow_oop_reg
2456          //
2457          // and on sparc:
2458          //
2459          //    Load_narrow_oop memory, narrow_oop_reg
2460          //    decode_not_null narrow_oop_reg, base_reg
2461          //    Load [base_reg + offset], val_reg
2462          //    NullCheck base_reg
2463          //
2464        } else if (t->isa_oopptr()) {
2465          new_in2 = ConNode::make(C, t->make_narrowoop());
2466        }
2467      }
2468      if (new_in2 != NULL) {
2469        Node* cmpN = new (C) CmpNNode(in1->in(1), new_in2);
2470        n->subsume_by( cmpN );
2471        if (in1->outcnt() == 0) {
2472          in1->disconnect_inputs(NULL);
2473        }
2474        if (in2->outcnt() == 0) {
2475          in2->disconnect_inputs(NULL);
2476        }
2477      }
2478    }
2479    break;
2480
2481  case Op_DecodeN:
2482    assert(!n->in(1)->is_EncodeP(), "should be optimized out");
2483    // DecodeN could be pinned when it can't be fold into
2484    // an address expression, see the code for Op_CastPP above.
2485    assert(n->in(0) == NULL || !Matcher::narrow_oop_use_complex_address(), "no control");
2486    break;
2487
2488  case Op_EncodeP: {
2489    Node* in1 = n->in(1);
2490    if (in1->is_DecodeN()) {
2491      n->subsume_by(in1->in(1));
2492    } else if (in1->Opcode() == Op_ConP) {
2493      Compile* C = Compile::current();
2494      const Type* t = in1->bottom_type();
2495      if (t == TypePtr::NULL_PTR) {
2496        n->subsume_by(ConNode::make(C, TypeNarrowOop::NULL_PTR));
2497      } else if (t->isa_oopptr()) {
2498        n->subsume_by(ConNode::make(C, t->make_narrowoop()));
2499      }
2500    }
2501    if (in1->outcnt() == 0) {
2502      in1->disconnect_inputs(NULL);
2503    }
2504    break;
2505  }
2506
2507  case Op_Proj: {
2508    if (OptimizeStringConcat) {
2509      ProjNode* p = n->as_Proj();
2510      if (p->_is_io_use) {
2511        // Separate projections were used for the exception path which
2512        // are normally removed by a late inline.  If it wasn't inlined
2513        // then they will hang around and should just be replaced with
2514        // the original one.
2515        Node* proj = NULL;
2516        // Replace with just one
2517        for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
2518          Node *use = i.get();
2519          if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
2520            proj = use;
2521            break;
2522          }
2523        }
2524        assert(proj != NULL, "must be found");
2525        p->subsume_by(proj);
2526      }
2527    }
2528    break;
2529  }
2530
2531  case Op_Phi:
2532    if (n->as_Phi()->bottom_type()->isa_narrowoop()) {
2533      // The EncodeP optimization may create Phi with the same edges
2534      // for all paths. It is not handled well by Register Allocator.
2535      Node* unique_in = n->in(1);
2536      assert(unique_in != NULL, "");
2537      uint cnt = n->req();
2538      for (uint i = 2; i < cnt; i++) {
2539        Node* m = n->in(i);
2540        assert(m != NULL, "");
2541        if (unique_in != m)
2542          unique_in = NULL;
2543      }
2544      if (unique_in != NULL) {
2545        n->subsume_by(unique_in);
2546      }
2547    }
2548    break;
2549
2550#endif
2551
2552  case Op_ModI:
2553    if (UseDivMod) {
2554      // Check if a%b and a/b both exist
2555      Node* d = n->find_similar(Op_DivI);
2556      if (d) {
2557        // Replace them with a fused divmod if supported
2558        Compile* C = Compile::current();
2559        if (Matcher::has_match_rule(Op_DivModI)) {
2560          DivModINode* divmod = DivModINode::make(C, n);
2561          d->subsume_by(divmod->div_proj());
2562          n->subsume_by(divmod->mod_proj());
2563        } else {
2564          // replace a%b with a-((a/b)*b)
2565          Node* mult = new (C) MulINode(d, d->in(2));
2566          Node* sub  = new (C) SubINode(d->in(1), mult);
2567          n->subsume_by( sub );
2568        }
2569      }
2570    }
2571    break;
2572
2573  case Op_ModL:
2574    if (UseDivMod) {
2575      // Check if a%b and a/b both exist
2576      Node* d = n->find_similar(Op_DivL);
2577      if (d) {
2578        // Replace them with a fused divmod if supported
2579        Compile* C = Compile::current();
2580        if (Matcher::has_match_rule(Op_DivModL)) {
2581          DivModLNode* divmod = DivModLNode::make(C, n);
2582          d->subsume_by(divmod->div_proj());
2583          n->subsume_by(divmod->mod_proj());
2584        } else {
2585          // replace a%b with a-((a/b)*b)
2586          Node* mult = new (C) MulLNode(d, d->in(2));
2587          Node* sub  = new (C) SubLNode(d->in(1), mult);
2588          n->subsume_by( sub );
2589        }
2590      }
2591    }
2592    break;
2593
2594  case Op_LoadVector:
2595  case Op_StoreVector:
2596    break;
2597
2598  case Op_PackB:
2599  case Op_PackS:
2600  case Op_PackI:
2601  case Op_PackF:
2602  case Op_PackL:
2603  case Op_PackD:
2604    if (n->req()-1 > 2) {
2605      // Replace many operand PackNodes with a binary tree for matching
2606      PackNode* p = (PackNode*) n;
2607      Node* btp = p->binary_tree_pack(Compile::current(), 1, n->req());
2608      n->subsume_by(btp);
2609    }
2610    break;
2611  case Op_Loop:
2612  case Op_CountedLoop:
2613    if (n->as_Loop()->is_inner_loop()) {
2614      frc.inc_inner_loop_count();
2615    }
2616    break;
2617  case Op_LShiftI:
2618  case Op_RShiftI:
2619  case Op_URShiftI:
2620  case Op_LShiftL:
2621  case Op_RShiftL:
2622  case Op_URShiftL:
2623    if (Matcher::need_masked_shift_count) {
2624      // The cpu's shift instructions don't restrict the count to the
2625      // lower 5/6 bits. We need to do the masking ourselves.
2626      Node* in2 = n->in(2);
2627      juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
2628      const TypeInt* t = in2->find_int_type();
2629      if (t != NULL && t->is_con()) {
2630        juint shift = t->get_con();
2631        if (shift > mask) { // Unsigned cmp
2632          Compile* C = Compile::current();
2633          n->set_req(2, ConNode::make(C, TypeInt::make(shift & mask)));
2634        }
2635      } else {
2636        if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
2637          Compile* C = Compile::current();
2638          Node* shift = new (C) AndINode(in2, ConNode::make(C, TypeInt::make(mask)));
2639          n->set_req(2, shift);
2640        }
2641      }
2642      if (in2->outcnt() == 0) { // Remove dead node
2643        in2->disconnect_inputs(NULL);
2644      }
2645    }
2646    break;
2647  default:
2648    assert( !n->is_Call(), "" );
2649    assert( !n->is_Mem(), "" );
2650    break;
2651  }
2652
2653  // Collect CFG split points
2654  if (n->is_MultiBranch())
2655    frc._tests.push(n);
2656}
2657
2658//------------------------------final_graph_reshaping_walk---------------------
2659// Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
2660// requires that the walk visits a node's inputs before visiting the node.
2661static void final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
2662  ResourceArea *area = Thread::current()->resource_area();
2663  Unique_Node_List sfpt(area);
2664
2665  frc._visited.set(root->_idx); // first, mark node as visited
2666  uint cnt = root->req();
2667  Node *n = root;
2668  uint  i = 0;
2669  while (true) {
2670    if (i < cnt) {
2671      // Place all non-visited non-null inputs onto stack
2672      Node* m = n->in(i);
2673      ++i;
2674      if (m != NULL && !frc._visited.test_set(m->_idx)) {
2675        if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL)
2676          sfpt.push(m);
2677        cnt = m->req();
2678        nstack.push(n, i); // put on stack parent and next input's index
2679        n = m;
2680        i = 0;
2681      }
2682    } else {
2683      // Now do post-visit work
2684      final_graph_reshaping_impl( n, frc );
2685      if (nstack.is_empty())
2686        break;             // finished
2687      n = nstack.node();   // Get node from stack
2688      cnt = n->req();
2689      i = nstack.index();
2690      nstack.pop();        // Shift to the next node on stack
2691    }
2692  }
2693
2694  // Skip next transformation if compressed oops are not used.
2695  if (!UseCompressedOops || !Matcher::gen_narrow_oop_implicit_null_checks())
2696    return;
2697
2698  // Go over safepoints nodes to skip DecodeN nodes for debug edges.
2699  // It could be done for an uncommon traps or any safepoints/calls
2700  // if the DecodeN node is referenced only in a debug info.
2701  while (sfpt.size() > 0) {
2702    n = sfpt.pop();
2703    JVMState *jvms = n->as_SafePoint()->jvms();
2704    assert(jvms != NULL, "sanity");
2705    int start = jvms->debug_start();
2706    int end   = n->req();
2707    bool is_uncommon = (n->is_CallStaticJava() &&
2708                        n->as_CallStaticJava()->uncommon_trap_request() != 0);
2709    for (int j = start; j < end; j++) {
2710      Node* in = n->in(j);
2711      if (in->is_DecodeN()) {
2712        bool safe_to_skip = true;
2713        if (!is_uncommon ) {
2714          // Is it safe to skip?
2715          for (uint i = 0; i < in->outcnt(); i++) {
2716            Node* u = in->raw_out(i);
2717            if (!u->is_SafePoint() ||
2718                 u->is_Call() && u->as_Call()->has_non_debug_use(n)) {
2719              safe_to_skip = false;
2720            }
2721          }
2722        }
2723        if (safe_to_skip) {
2724          n->set_req(j, in->in(1));
2725        }
2726        if (in->outcnt() == 0) {
2727          in->disconnect_inputs(NULL);
2728        }
2729      }
2730    }
2731  }
2732}
2733
2734//------------------------------final_graph_reshaping--------------------------
2735// Final Graph Reshaping.
2736//
2737// (1) Clone simple inputs to uncommon calls, so they can be scheduled late
2738//     and not commoned up and forced early.  Must come after regular
2739//     optimizations to avoid GVN undoing the cloning.  Clone constant
2740//     inputs to Loop Phis; these will be split by the allocator anyways.
2741//     Remove Opaque nodes.
2742// (2) Move last-uses by commutative operations to the left input to encourage
2743//     Intel update-in-place two-address operations and better register usage
2744//     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
2745//     calls canonicalizing them back.
2746// (3) Count the number of double-precision FP ops, single-precision FP ops
2747//     and call sites.  On Intel, we can get correct rounding either by
2748//     forcing singles to memory (requires extra stores and loads after each
2749//     FP bytecode) or we can set a rounding mode bit (requires setting and
2750//     clearing the mode bit around call sites).  The mode bit is only used
2751//     if the relative frequency of single FP ops to calls is low enough.
2752//     This is a key transform for SPEC mpeg_audio.
2753// (4) Detect infinite loops; blobs of code reachable from above but not
2754//     below.  Several of the Code_Gen algorithms fail on such code shapes,
2755//     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
2756//     from time to time in other codes (such as -Xcomp finalizer loops, etc).
2757//     Detection is by looking for IfNodes where only 1 projection is
2758//     reachable from below or CatchNodes missing some targets.
2759// (5) Assert for insane oop offsets in debug mode.
2760
2761bool Compile::final_graph_reshaping() {
2762  // an infinite loop may have been eliminated by the optimizer,
2763  // in which case the graph will be empty.
2764  if (root()->req() == 1) {
2765    record_method_not_compilable("trivial infinite loop");
2766    return true;
2767  }
2768
2769  Final_Reshape_Counts frc;
2770
2771  // Visit everybody reachable!
2772  // Allocate stack of size C->unique()/2 to avoid frequent realloc
2773  Node_Stack nstack(unique() >> 1);
2774  final_graph_reshaping_walk(nstack, root(), frc);
2775
2776  // Check for unreachable (from below) code (i.e., infinite loops).
2777  for( uint i = 0; i < frc._tests.size(); i++ ) {
2778    MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
2779    // Get number of CFG targets.
2780    // Note that PCTables include exception targets after calls.
2781    uint required_outcnt = n->required_outcnt();
2782    if (n->outcnt() != required_outcnt) {
2783      // Check for a few special cases.  Rethrow Nodes never take the
2784      // 'fall-thru' path, so expected kids is 1 less.
2785      if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
2786        if (n->in(0)->in(0)->is_Call()) {
2787          CallNode *call = n->in(0)->in(0)->as_Call();
2788          if (call->entry_point() == OptoRuntime::rethrow_stub()) {
2789            required_outcnt--;      // Rethrow always has 1 less kid
2790          } else if (call->req() > TypeFunc::Parms &&
2791                     call->is_CallDynamicJava()) {
2792            // Check for null receiver. In such case, the optimizer has
2793            // detected that the virtual call will always result in a null
2794            // pointer exception. The fall-through projection of this CatchNode
2795            // will not be populated.
2796            Node *arg0 = call->in(TypeFunc::Parms);
2797            if (arg0->is_Type() &&
2798                arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
2799              required_outcnt--;
2800            }
2801          } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
2802                     call->req() > TypeFunc::Parms+1 &&
2803                     call->is_CallStaticJava()) {
2804            // Check for negative array length. In such case, the optimizer has
2805            // detected that the allocation attempt will always result in an
2806            // exception. There is no fall-through projection of this CatchNode .
2807            Node *arg1 = call->in(TypeFunc::Parms+1);
2808            if (arg1->is_Type() &&
2809                arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
2810              required_outcnt--;
2811            }
2812          }
2813        }
2814      }
2815      // Recheck with a better notion of 'required_outcnt'
2816      if (n->outcnt() != required_outcnt) {
2817        record_method_not_compilable("malformed control flow");
2818        return true;            // Not all targets reachable!
2819      }
2820    }
2821    // Check that I actually visited all kids.  Unreached kids
2822    // must be infinite loops.
2823    for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
2824      if (!frc._visited.test(n->fast_out(j)->_idx)) {
2825        record_method_not_compilable("infinite loop");
2826        return true;            // Found unvisited kid; must be unreach
2827      }
2828  }
2829
2830  // If original bytecodes contained a mixture of floats and doubles
2831  // check if the optimizer has made it homogenous, item (3).
2832  if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
2833      frc.get_float_count() > 32 &&
2834      frc.get_double_count() == 0 &&
2835      (10 * frc.get_call_count() < frc.get_float_count()) ) {
2836    set_24_bit_selection_and_mode( false,  true );
2837  }
2838
2839  set_java_calls(frc.get_java_call_count());
2840  set_inner_loops(frc.get_inner_loop_count());
2841
2842  // No infinite loops, no reason to bail out.
2843  return false;
2844}
2845
2846//-----------------------------too_many_traps----------------------------------
2847// Report if there are too many traps at the current method and bci.
2848// Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
2849bool Compile::too_many_traps(ciMethod* method,
2850                             int bci,
2851                             Deoptimization::DeoptReason reason) {
2852  ciMethodData* md = method->method_data();
2853  if (md->is_empty()) {
2854    // Assume the trap has not occurred, or that it occurred only
2855    // because of a transient condition during start-up in the interpreter.
2856    return false;
2857  }
2858  if (md->has_trap_at(bci, reason) != 0) {
2859    // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
2860    // Also, if there are multiple reasons, or if there is no per-BCI record,
2861    // assume the worst.
2862    if (log())
2863      log()->elem("observe trap='%s' count='%d'",
2864                  Deoptimization::trap_reason_name(reason),
2865                  md->trap_count(reason));
2866    return true;
2867  } else {
2868    // Ignore method/bci and see if there have been too many globally.
2869    return too_many_traps(reason, md);
2870  }
2871}
2872
2873// Less-accurate variant which does not require a method and bci.
2874bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
2875                             ciMethodData* logmd) {
2876 if (trap_count(reason) >= (uint)PerMethodTrapLimit) {
2877    // Too many traps globally.
2878    // Note that we use cumulative trap_count, not just md->trap_count.
2879    if (log()) {
2880      int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
2881      log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
2882                  Deoptimization::trap_reason_name(reason),
2883                  mcount, trap_count(reason));
2884    }
2885    return true;
2886  } else {
2887    // The coast is clear.
2888    return false;
2889  }
2890}
2891
2892//--------------------------too_many_recompiles--------------------------------
2893// Report if there are too many recompiles at the current method and bci.
2894// Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
2895// Is not eager to return true, since this will cause the compiler to use
2896// Action_none for a trap point, to avoid too many recompilations.
2897bool Compile::too_many_recompiles(ciMethod* method,
2898                                  int bci,
2899                                  Deoptimization::DeoptReason reason) {
2900  ciMethodData* md = method->method_data();
2901  if (md->is_empty()) {
2902    // Assume the trap has not occurred, or that it occurred only
2903    // because of a transient condition during start-up in the interpreter.
2904    return false;
2905  }
2906  // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
2907  uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
2908  uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
2909  Deoptimization::DeoptReason per_bc_reason
2910    = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
2911  if ((per_bc_reason == Deoptimization::Reason_none
2912       || md->has_trap_at(bci, reason) != 0)
2913      // The trap frequency measure we care about is the recompile count:
2914      && md->trap_recompiled_at(bci)
2915      && md->overflow_recompile_count() >= bc_cutoff) {
2916    // Do not emit a trap here if it has already caused recompilations.
2917    // Also, if there are multiple reasons, or if there is no per-BCI record,
2918    // assume the worst.
2919    if (log())
2920      log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
2921                  Deoptimization::trap_reason_name(reason),
2922                  md->trap_count(reason),
2923                  md->overflow_recompile_count());
2924    return true;
2925  } else if (trap_count(reason) != 0
2926             && decompile_count() >= m_cutoff) {
2927    // Too many recompiles globally, and we have seen this sort of trap.
2928    // Use cumulative decompile_count, not just md->decompile_count.
2929    if (log())
2930      log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
2931                  Deoptimization::trap_reason_name(reason),
2932                  md->trap_count(reason), trap_count(reason),
2933                  md->decompile_count(), decompile_count());
2934    return true;
2935  } else {
2936    // The coast is clear.
2937    return false;
2938  }
2939}
2940
2941
2942#ifndef PRODUCT
2943//------------------------------verify_graph_edges---------------------------
2944// Walk the Graph and verify that there is a one-to-one correspondence
2945// between Use-Def edges and Def-Use edges in the graph.
2946void Compile::verify_graph_edges(bool no_dead_code) {
2947  if (VerifyGraphEdges) {
2948    ResourceArea *area = Thread::current()->resource_area();
2949    Unique_Node_List visited(area);
2950    // Call recursive graph walk to check edges
2951    _root->verify_edges(visited);
2952    if (no_dead_code) {
2953      // Now make sure that no visited node is used by an unvisited node.
2954      bool dead_nodes = 0;
2955      Unique_Node_List checked(area);
2956      while (visited.size() > 0) {
2957        Node* n = visited.pop();
2958        checked.push(n);
2959        for (uint i = 0; i < n->outcnt(); i++) {
2960          Node* use = n->raw_out(i);
2961          if (checked.member(use))  continue;  // already checked
2962          if (visited.member(use))  continue;  // already in the graph
2963          if (use->is_Con())        continue;  // a dead ConNode is OK
2964          // At this point, we have found a dead node which is DU-reachable.
2965          if (dead_nodes++ == 0)
2966            tty->print_cr("*** Dead nodes reachable via DU edges:");
2967          use->dump(2);
2968          tty->print_cr("---");
2969          checked.push(use);  // No repeats; pretend it is now checked.
2970        }
2971      }
2972      assert(dead_nodes == 0, "using nodes must be reachable from root");
2973    }
2974  }
2975}
2976#endif
2977
2978// The Compile object keeps track of failure reasons separately from the ciEnv.
2979// This is required because there is not quite a 1-1 relation between the
2980// ciEnv and its compilation task and the Compile object.  Note that one
2981// ciEnv might use two Compile objects, if C2Compiler::compile_method decides
2982// to backtrack and retry without subsuming loads.  Other than this backtracking
2983// behavior, the Compile's failure reason is quietly copied up to the ciEnv
2984// by the logic in C2Compiler.
2985void Compile::record_failure(const char* reason) {
2986  if (log() != NULL) {
2987    log()->elem("failure reason='%s' phase='compile'", reason);
2988  }
2989  if (_failure_reason == NULL) {
2990    // Record the first failure reason.
2991    _failure_reason = reason;
2992  }
2993  if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
2994    C->print_method(_failure_reason);
2995  }
2996  _root = NULL;  // flush the graph, too
2997}
2998
2999Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator, bool dolog)
3000  : TraceTime(NULL, accumulator, false NOT_PRODUCT( || TimeCompiler ), false)
3001{
3002  if (dolog) {
3003    C = Compile::current();
3004    _log = C->log();
3005  } else {
3006    C = NULL;
3007    _log = NULL;
3008  }
3009  if (_log != NULL) {
3010    _log->begin_head("phase name='%s' nodes='%d'", name, C->unique());
3011    _log->stamp();
3012    _log->end_head();
3013  }
3014}
3015
3016Compile::TracePhase::~TracePhase() {
3017  if (_log != NULL) {
3018    _log->done("phase nodes='%d'", C->unique());
3019  }
3020}
3021
3022//=============================================================================
3023// Two Constant's are equal when the type and the value are equal.
3024bool Compile::Constant::operator==(const Constant& other) {
3025  if (type()          != other.type()         )  return false;
3026  if (can_be_reused() != other.can_be_reused())  return false;
3027  // For floating point values we compare the bit pattern.
3028  switch (type()) {
3029  case T_FLOAT:   return (_v._value.i == other._v._value.i);
3030  case T_LONG:
3031  case T_DOUBLE:  return (_v._value.j == other._v._value.j);
3032  case T_OBJECT:
3033  case T_METADATA: return (_v._metadata == other._v._metadata);
3034  case T_ADDRESS: return (_v._value.l == other._v._value.l);
3035  case T_VOID:    return (_v._value.l == other._v._value.l);  // jump-table entries
3036  default: ShouldNotReachHere();
3037  }
3038  return false;
3039}
3040
3041static int type_to_size_in_bytes(BasicType t) {
3042  switch (t) {
3043  case T_LONG:    return sizeof(jlong  );
3044  case T_FLOAT:   return sizeof(jfloat );
3045  case T_DOUBLE:  return sizeof(jdouble);
3046  case T_METADATA: return sizeof(Metadata*);
3047    // We use T_VOID as marker for jump-table entries (labels) which
3048    // need an internal word relocation.
3049  case T_VOID:
3050  case T_ADDRESS:
3051  case T_OBJECT:  return sizeof(jobject);
3052  }
3053
3054  ShouldNotReachHere();
3055  return -1;
3056}
3057
3058int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
3059  // sort descending
3060  if (a->freq() > b->freq())  return -1;
3061  if (a->freq() < b->freq())  return  1;
3062  return 0;
3063}
3064
3065void Compile::ConstantTable::calculate_offsets_and_size() {
3066  // First, sort the array by frequencies.
3067  _constants.sort(qsort_comparator);
3068
3069#ifdef ASSERT
3070  // Make sure all jump-table entries were sorted to the end of the
3071  // array (they have a negative frequency).
3072  bool found_void = false;
3073  for (int i = 0; i < _constants.length(); i++) {
3074    Constant con = _constants.at(i);
3075    if (con.type() == T_VOID)
3076      found_void = true;  // jump-tables
3077    else
3078      assert(!found_void, "wrong sorting");
3079  }
3080#endif
3081
3082  int offset = 0;
3083  for (int i = 0; i < _constants.length(); i++) {
3084    Constant* con = _constants.adr_at(i);
3085
3086    // Align offset for type.
3087    int typesize = type_to_size_in_bytes(con->type());
3088    offset = align_size_up(offset, typesize);
3089    con->set_offset(offset);   // set constant's offset
3090
3091    if (con->type() == T_VOID) {
3092      MachConstantNode* n = (MachConstantNode*) con->get_jobject();
3093      offset = offset + typesize * n->outcnt();  // expand jump-table
3094    } else {
3095      offset = offset + typesize;
3096    }
3097  }
3098
3099  // Align size up to the next section start (which is insts; see
3100  // CodeBuffer::align_at_start).
3101  assert(_size == -1, "already set?");
3102  _size = align_size_up(offset, CodeEntryAlignment);
3103}
3104
3105void Compile::ConstantTable::emit(CodeBuffer& cb) {
3106  MacroAssembler _masm(&cb);
3107  for (int i = 0; i < _constants.length(); i++) {
3108    Constant con = _constants.at(i);
3109    address constant_addr;
3110    switch (con.type()) {
3111    case T_LONG:   constant_addr = _masm.long_constant(  con.get_jlong()  ); break;
3112    case T_FLOAT:  constant_addr = _masm.float_constant( con.get_jfloat() ); break;
3113    case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
3114    case T_OBJECT: {
3115      jobject obj = con.get_jobject();
3116      int oop_index = _masm.oop_recorder()->find_index(obj);
3117      constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
3118      break;
3119    }
3120    case T_ADDRESS: {
3121      address addr = (address) con.get_jobject();
3122      constant_addr = _masm.address_constant(addr);
3123      break;
3124    }
3125    // We use T_VOID as marker for jump-table entries (labels) which
3126    // need an internal word relocation.
3127    case T_VOID: {
3128      MachConstantNode* n = (MachConstantNode*) con.get_jobject();
3129      // Fill the jump-table with a dummy word.  The real value is
3130      // filled in later in fill_jump_table.
3131      address dummy = (address) n;
3132      constant_addr = _masm.address_constant(dummy);
3133      // Expand jump-table
3134      for (uint i = 1; i < n->outcnt(); i++) {
3135        address temp_addr = _masm.address_constant(dummy + i);
3136        assert(temp_addr, "consts section too small");
3137      }
3138      break;
3139    }
3140    case T_METADATA: {
3141      Metadata* obj = con.get_metadata();
3142      int metadata_index = _masm.oop_recorder()->find_index(obj);
3143      constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
3144      break;
3145    }
3146    default: ShouldNotReachHere();
3147    }
3148    assert(constant_addr, "consts section too small");
3149    assert((constant_addr - _masm.code()->consts()->start()) == con.offset(), err_msg_res("must be: %d == %d", constant_addr - _masm.code()->consts()->start(), con.offset()));
3150  }
3151}
3152
3153int Compile::ConstantTable::find_offset(Constant& con) const {
3154  int idx = _constants.find(con);
3155  assert(idx != -1, "constant must be in constant table");
3156  int offset = _constants.at(idx).offset();
3157  assert(offset != -1, "constant table not emitted yet?");
3158  return offset;
3159}
3160
3161void Compile::ConstantTable::add(Constant& con) {
3162  if (con.can_be_reused()) {
3163    int idx = _constants.find(con);
3164    if (idx != -1 && _constants.at(idx).can_be_reused()) {
3165      _constants.adr_at(idx)->inc_freq(con.freq());  // increase the frequency by the current value
3166      return;
3167    }
3168  }
3169  (void) _constants.append(con);
3170}
3171
3172Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
3173  Block* b = Compile::current()->cfg()->_bbs[n->_idx];
3174  Constant con(type, value, b->_freq);
3175  add(con);
3176  return con;
3177}
3178
3179Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
3180  Constant con(metadata);
3181  add(con);
3182  return con;
3183}
3184
3185Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
3186  jvalue value;
3187  BasicType type = oper->type()->basic_type();
3188  switch (type) {
3189  case T_LONG:    value.j = oper->constantL(); break;
3190  case T_FLOAT:   value.f = oper->constantF(); break;
3191  case T_DOUBLE:  value.d = oper->constantD(); break;
3192  case T_OBJECT:
3193  case T_ADDRESS: value.l = (jobject) oper->constant(); break;
3194  case T_METADATA: return add((Metadata*)oper->constant()); break;
3195  default: guarantee(false, err_msg_res("unhandled type: %s", type2name(type)));
3196  }
3197  return add(n, type, value);
3198}
3199
3200Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
3201  jvalue value;
3202  // We can use the node pointer here to identify the right jump-table
3203  // as this method is called from Compile::Fill_buffer right before
3204  // the MachNodes are emitted and the jump-table is filled (means the
3205  // MachNode pointers do not change anymore).
3206  value.l = (jobject) n;
3207  Constant con(T_VOID, value, next_jump_table_freq(), false);  // Labels of a jump-table cannot be reused.
3208  add(con);
3209  return con;
3210}
3211
3212void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
3213  // If called from Compile::scratch_emit_size do nothing.
3214  if (Compile::current()->in_scratch_emit_size())  return;
3215
3216  assert(labels.is_nonempty(), "must be");
3217  assert((uint) labels.length() == n->outcnt(), err_msg_res("must be equal: %d == %d", labels.length(), n->outcnt()));
3218
3219  // Since MachConstantNode::constant_offset() also contains
3220  // table_base_offset() we need to subtract the table_base_offset()
3221  // to get the plain offset into the constant table.
3222  int offset = n->constant_offset() - table_base_offset();
3223
3224  MacroAssembler _masm(&cb);
3225  address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
3226
3227  for (uint i = 0; i < n->outcnt(); i++) {
3228    address* constant_addr = &jump_table_base[i];
3229    assert(*constant_addr == (((address) n) + i), err_msg_res("all jump-table entries must contain adjusted node pointer: " INTPTR_FORMAT " == " INTPTR_FORMAT, *constant_addr, (((address) n) + i)));
3230    *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
3231    cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
3232  }
3233}
3234