parse2.cpp revision 6557:6ad207fd3e26
1/*
2 * Copyright (c) 1998, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25#include "precompiled.hpp"
26#include "ci/ciMethodData.hpp"
27#include "classfile/systemDictionary.hpp"
28#include "classfile/vmSymbols.hpp"
29#include "compiler/compileLog.hpp"
30#include "interpreter/linkResolver.hpp"
31#include "memory/universe.inline.hpp"
32#include "opto/addnode.hpp"
33#include "opto/castnode.hpp"
34#include "opto/convertnode.hpp"
35#include "opto/divnode.hpp"
36#include "opto/idealGraphPrinter.hpp"
37#include "opto/matcher.hpp"
38#include "opto/memnode.hpp"
39#include "opto/mulnode.hpp"
40#include "opto/parse.hpp"
41#include "opto/runtime.hpp"
42#include "runtime/deoptimization.hpp"
43#include "runtime/sharedRuntime.hpp"
44
45extern int explicit_null_checks_inserted,
46           explicit_null_checks_elided;
47
48//---------------------------------array_load----------------------------------
49void Parse::array_load(BasicType elem_type) {
50  const Type* elem = Type::TOP;
51  Node* adr = array_addressing(elem_type, 0, &elem);
52  if (stopped())  return;     // guaranteed null or range check
53  dec_sp(2);                  // Pop array and index
54  const TypeAryPtr* adr_type = TypeAryPtr::get_array_body_type(elem_type);
55  Node* ld = make_load(control(), adr, elem, elem_type, adr_type, MemNode::unordered);
56  push(ld);
57}
58
59
60//--------------------------------array_store----------------------------------
61void Parse::array_store(BasicType elem_type) {
62  Node* adr = array_addressing(elem_type, 1);
63  if (stopped())  return;     // guaranteed null or range check
64  Node* val = pop();
65  dec_sp(2);                  // Pop array and index
66  const TypeAryPtr* adr_type = TypeAryPtr::get_array_body_type(elem_type);
67  store_to_memory(control(), adr, val, elem_type, adr_type, StoreNode::release_if_reference(elem_type));
68}
69
70
71//------------------------------array_addressing-------------------------------
72// Pull array and index from the stack.  Compute pointer-to-element.
73Node* Parse::array_addressing(BasicType type, int vals, const Type* *result2) {
74  Node *idx   = peek(0+vals);   // Get from stack without popping
75  Node *ary   = peek(1+vals);   // in case of exception
76
77  // Null check the array base, with correct stack contents
78  ary = null_check(ary, T_ARRAY);
79  // Compile-time detect of null-exception?
80  if (stopped())  return top();
81
82  const TypeAryPtr* arytype  = _gvn.type(ary)->is_aryptr();
83  const TypeInt*    sizetype = arytype->size();
84  const Type*       elemtype = arytype->elem();
85
86  if (UseUniqueSubclasses && result2 != NULL) {
87    const Type* el = elemtype->make_ptr();
88    if (el && el->isa_instptr()) {
89      const TypeInstPtr* toop = el->is_instptr();
90      if (toop->klass()->as_instance_klass()->unique_concrete_subklass()) {
91        // If we load from "AbstractClass[]" we must see "ConcreteSubClass".
92        const Type* subklass = Type::get_const_type(toop->klass());
93        elemtype = subklass->join_speculative(el);
94      }
95    }
96  }
97
98  // Check for big class initializers with all constant offsets
99  // feeding into a known-size array.
100  const TypeInt* idxtype = _gvn.type(idx)->is_int();
101  // See if the highest idx value is less than the lowest array bound,
102  // and if the idx value cannot be negative:
103  bool need_range_check = true;
104  if (idxtype->_hi < sizetype->_lo && idxtype->_lo >= 0) {
105    need_range_check = false;
106    if (C->log() != NULL)   C->log()->elem("observe that='!need_range_check'");
107  }
108
109  ciKlass * arytype_klass = arytype->klass();
110  if ((arytype_klass != NULL) && (!arytype_klass->is_loaded())) {
111    // Only fails for some -Xcomp runs
112    // The class is unloaded.  We have to run this bytecode in the interpreter.
113    uncommon_trap(Deoptimization::Reason_unloaded,
114                  Deoptimization::Action_reinterpret,
115                  arytype->klass(), "!loaded array");
116    return top();
117  }
118
119  // Do the range check
120  if (GenerateRangeChecks && need_range_check) {
121    Node* tst;
122    if (sizetype->_hi <= 0) {
123      // The greatest array bound is negative, so we can conclude that we're
124      // compiling unreachable code, but the unsigned compare trick used below
125      // only works with non-negative lengths.  Instead, hack "tst" to be zero so
126      // the uncommon_trap path will always be taken.
127      tst = _gvn.intcon(0);
128    } else {
129      // Range is constant in array-oop, so we can use the original state of mem
130      Node* len = load_array_length(ary);
131
132      // Test length vs index (standard trick using unsigned compare)
133      Node* chk = _gvn.transform( new CmpUNode(idx, len) );
134      BoolTest::mask btest = BoolTest::lt;
135      tst = _gvn.transform( new BoolNode(chk, btest) );
136    }
137    // Branch to failure if out of bounds
138    { BuildCutout unless(this, tst, PROB_MAX);
139      if (C->allow_range_check_smearing()) {
140        // Do not use builtin_throw, since range checks are sometimes
141        // made more stringent by an optimistic transformation.
142        // This creates "tentative" range checks at this point,
143        // which are not guaranteed to throw exceptions.
144        // See IfNode::Ideal, is_range_check, adjust_check.
145        uncommon_trap(Deoptimization::Reason_range_check,
146                      Deoptimization::Action_make_not_entrant,
147                      NULL, "range_check");
148      } else {
149        // If we have already recompiled with the range-check-widening
150        // heroic optimization turned off, then we must really be throwing
151        // range check exceptions.
152        builtin_throw(Deoptimization::Reason_range_check, idx);
153      }
154    }
155  }
156  // Check for always knowing you are throwing a range-check exception
157  if (stopped())  return top();
158
159  Node* ptr = array_element_address(ary, idx, type, sizetype);
160
161  if (result2 != NULL)  *result2 = elemtype;
162
163  assert(ptr != top(), "top should go hand-in-hand with stopped");
164
165  return ptr;
166}
167
168
169// returns IfNode
170IfNode* Parse::jump_if_fork_int(Node* a, Node* b, BoolTest::mask mask) {
171  Node   *cmp = _gvn.transform( new CmpINode( a, b)); // two cases: shiftcount > 32 and shiftcount <= 32
172  Node   *tst = _gvn.transform( new BoolNode( cmp, mask));
173  IfNode *iff = create_and_map_if( control(), tst, ((mask == BoolTest::eq) ? PROB_STATIC_INFREQUENT : PROB_FAIR), COUNT_UNKNOWN );
174  return iff;
175}
176
177// return Region node
178Node* Parse::jump_if_join(Node* iffalse, Node* iftrue) {
179  Node *region  = new RegionNode(3); // 2 results
180  record_for_igvn(region);
181  region->init_req(1, iffalse);
182  region->init_req(2, iftrue );
183  _gvn.set_type(region, Type::CONTROL);
184  region = _gvn.transform(region);
185  set_control (region);
186  return region;
187}
188
189
190//------------------------------helper for tableswitch-------------------------
191void Parse::jump_if_true_fork(IfNode *iff, int dest_bci_if_true, int prof_table_index) {
192  // True branch, use existing map info
193  { PreserveJVMState pjvms(this);
194    Node *iftrue  = _gvn.transform( new IfTrueNode (iff) );
195    set_control( iftrue );
196    profile_switch_case(prof_table_index);
197    merge_new_path(dest_bci_if_true);
198  }
199
200  // False branch
201  Node *iffalse = _gvn.transform( new IfFalseNode(iff) );
202  set_control( iffalse );
203}
204
205void Parse::jump_if_false_fork(IfNode *iff, int dest_bci_if_true, int prof_table_index) {
206  // True branch, use existing map info
207  { PreserveJVMState pjvms(this);
208    Node *iffalse  = _gvn.transform( new IfFalseNode (iff) );
209    set_control( iffalse );
210    profile_switch_case(prof_table_index);
211    merge_new_path(dest_bci_if_true);
212  }
213
214  // False branch
215  Node *iftrue = _gvn.transform( new IfTrueNode(iff) );
216  set_control( iftrue );
217}
218
219void Parse::jump_if_always_fork(int dest_bci, int prof_table_index) {
220  // False branch, use existing map and control()
221  profile_switch_case(prof_table_index);
222  merge_new_path(dest_bci);
223}
224
225
226extern "C" {
227  static int jint_cmp(const void *i, const void *j) {
228    int a = *(jint *)i;
229    int b = *(jint *)j;
230    return a > b ? 1 : a < b ? -1 : 0;
231  }
232}
233
234
235// Default value for methodData switch indexing. Must be a negative value to avoid
236// conflict with any legal switch index.
237#define NullTableIndex -1
238
239class SwitchRange : public StackObj {
240  // a range of integers coupled with a bci destination
241  jint _lo;                     // inclusive lower limit
242  jint _hi;                     // inclusive upper limit
243  int _dest;
244  int _table_index;             // index into method data table
245
246public:
247  jint lo() const              { return _lo;   }
248  jint hi() const              { return _hi;   }
249  int  dest() const            { return _dest; }
250  int  table_index() const     { return _table_index; }
251  bool is_singleton() const    { return _lo == _hi; }
252
253  void setRange(jint lo, jint hi, int dest, int table_index) {
254    assert(lo <= hi, "must be a non-empty range");
255    _lo = lo, _hi = hi; _dest = dest; _table_index = table_index;
256  }
257  bool adjoinRange(jint lo, jint hi, int dest, int table_index) {
258    assert(lo <= hi, "must be a non-empty range");
259    if (lo == _hi+1 && dest == _dest && table_index == _table_index) {
260      _hi = hi;
261      return true;
262    }
263    return false;
264  }
265
266  void set (jint value, int dest, int table_index) {
267    setRange(value, value, dest, table_index);
268  }
269  bool adjoin(jint value, int dest, int table_index) {
270    return adjoinRange(value, value, dest, table_index);
271  }
272
273  void print() {
274    if (is_singleton())
275      tty->print(" {%d}=>%d", lo(), dest());
276    else if (lo() == min_jint)
277      tty->print(" {..%d}=>%d", hi(), dest());
278    else if (hi() == max_jint)
279      tty->print(" {%d..}=>%d", lo(), dest());
280    else
281      tty->print(" {%d..%d}=>%d", lo(), hi(), dest());
282  }
283};
284
285
286//-------------------------------do_tableswitch--------------------------------
287void Parse::do_tableswitch() {
288  Node* lookup = pop();
289
290  // Get information about tableswitch
291  int default_dest = iter().get_dest_table(0);
292  int lo_index     = iter().get_int_table(1);
293  int hi_index     = iter().get_int_table(2);
294  int len          = hi_index - lo_index + 1;
295
296  if (len < 1) {
297    // If this is a backward branch, add safepoint
298    maybe_add_safepoint(default_dest);
299    merge(default_dest);
300    return;
301  }
302
303  // generate decision tree, using trichotomy when possible
304  int rnum = len+2;
305  bool makes_backward_branch = false;
306  SwitchRange* ranges = NEW_RESOURCE_ARRAY(SwitchRange, rnum);
307  int rp = -1;
308  if (lo_index != min_jint) {
309    ranges[++rp].setRange(min_jint, lo_index-1, default_dest, NullTableIndex);
310  }
311  for (int j = 0; j < len; j++) {
312    jint match_int = lo_index+j;
313    int  dest      = iter().get_dest_table(j+3);
314    makes_backward_branch |= (dest <= bci());
315    int  table_index = method_data_update() ? j : NullTableIndex;
316    if (rp < 0 || !ranges[rp].adjoin(match_int, dest, table_index)) {
317      ranges[++rp].set(match_int, dest, table_index);
318    }
319  }
320  jint highest = lo_index+(len-1);
321  assert(ranges[rp].hi() == highest, "");
322  if (highest != max_jint
323      && !ranges[rp].adjoinRange(highest+1, max_jint, default_dest, NullTableIndex)) {
324    ranges[++rp].setRange(highest+1, max_jint, default_dest, NullTableIndex);
325  }
326  assert(rp < len+2, "not too many ranges");
327
328  // Safepoint in case if backward branch observed
329  if( makes_backward_branch && UseLoopSafepoints )
330    add_safepoint();
331
332  jump_switch_ranges(lookup, &ranges[0], &ranges[rp]);
333}
334
335
336//------------------------------do_lookupswitch--------------------------------
337void Parse::do_lookupswitch() {
338  Node *lookup = pop();         // lookup value
339  // Get information about lookupswitch
340  int default_dest = iter().get_dest_table(0);
341  int len          = iter().get_int_table(1);
342
343  if (len < 1) {    // If this is a backward branch, add safepoint
344    maybe_add_safepoint(default_dest);
345    merge(default_dest);
346    return;
347  }
348
349  // generate decision tree, using trichotomy when possible
350  jint* table = NEW_RESOURCE_ARRAY(jint, len*2);
351  {
352    for( int j = 0; j < len; j++ ) {
353      table[j+j+0] = iter().get_int_table(2+j+j);
354      table[j+j+1] = iter().get_dest_table(2+j+j+1);
355    }
356    qsort( table, len, 2*sizeof(table[0]), jint_cmp );
357  }
358
359  int rnum = len*2+1;
360  bool makes_backward_branch = false;
361  SwitchRange* ranges = NEW_RESOURCE_ARRAY(SwitchRange, rnum);
362  int rp = -1;
363  for( int j = 0; j < len; j++ ) {
364    jint match_int   = table[j+j+0];
365    int  dest        = table[j+j+1];
366    int  next_lo     = rp < 0 ? min_jint : ranges[rp].hi()+1;
367    int  table_index = method_data_update() ? j : NullTableIndex;
368    makes_backward_branch |= (dest <= bci());
369    if( match_int != next_lo ) {
370      ranges[++rp].setRange(next_lo, match_int-1, default_dest, NullTableIndex);
371    }
372    if( rp < 0 || !ranges[rp].adjoin(match_int, dest, table_index) ) {
373      ranges[++rp].set(match_int, dest, table_index);
374    }
375  }
376  jint highest = table[2*(len-1)];
377  assert(ranges[rp].hi() == highest, "");
378  if( highest != max_jint
379      && !ranges[rp].adjoinRange(highest+1, max_jint, default_dest, NullTableIndex) ) {
380    ranges[++rp].setRange(highest+1, max_jint, default_dest, NullTableIndex);
381  }
382  assert(rp < rnum, "not too many ranges");
383
384  // Safepoint in case backward branch observed
385  if( makes_backward_branch && UseLoopSafepoints )
386    add_safepoint();
387
388  jump_switch_ranges(lookup, &ranges[0], &ranges[rp]);
389}
390
391//----------------------------create_jump_tables-------------------------------
392bool Parse::create_jump_tables(Node* key_val, SwitchRange* lo, SwitchRange* hi) {
393  // Are jumptables enabled
394  if (!UseJumpTables)  return false;
395
396  // Are jumptables supported
397  if (!Matcher::has_match_rule(Op_Jump))  return false;
398
399  // Don't make jump table if profiling
400  if (method_data_update())  return false;
401
402  // Decide if a guard is needed to lop off big ranges at either (or
403  // both) end(s) of the input set. We'll call this the default target
404  // even though we can't be sure that it is the true "default".
405
406  bool needs_guard = false;
407  int default_dest;
408  int64_t total_outlier_size = 0;
409  int64_t hi_size = ((int64_t)hi->hi()) - ((int64_t)hi->lo()) + 1;
410  int64_t lo_size = ((int64_t)lo->hi()) - ((int64_t)lo->lo()) + 1;
411
412  if (lo->dest() == hi->dest()) {
413    total_outlier_size = hi_size + lo_size;
414    default_dest = lo->dest();
415  } else if (lo_size > hi_size) {
416    total_outlier_size = lo_size;
417    default_dest = lo->dest();
418  } else {
419    total_outlier_size = hi_size;
420    default_dest = hi->dest();
421  }
422
423  // If a guard test will eliminate very sparse end ranges, then
424  // it is worth the cost of an extra jump.
425  if (total_outlier_size > (MaxJumpTableSparseness * 4)) {
426    needs_guard = true;
427    if (default_dest == lo->dest()) lo++;
428    if (default_dest == hi->dest()) hi--;
429  }
430
431  // Find the total number of cases and ranges
432  int64_t num_cases = ((int64_t)hi->hi()) - ((int64_t)lo->lo()) + 1;
433  int num_range = hi - lo + 1;
434
435  // Don't create table if: too large, too small, or too sparse.
436  if (num_cases < MinJumpTableSize || num_cases > MaxJumpTableSize)
437    return false;
438  if (num_cases > (MaxJumpTableSparseness * num_range))
439    return false;
440
441  // Normalize table lookups to zero
442  int lowval = lo->lo();
443  key_val = _gvn.transform( new SubINode(key_val, _gvn.intcon(lowval)) );
444
445  // Generate a guard to protect against input keyvals that aren't
446  // in the switch domain.
447  if (needs_guard) {
448    Node*   size = _gvn.intcon(num_cases);
449    Node*   cmp = _gvn.transform( new CmpUNode(key_val, size) );
450    Node*   tst = _gvn.transform( new BoolNode(cmp, BoolTest::ge) );
451    IfNode* iff = create_and_map_if( control(), tst, PROB_FAIR, COUNT_UNKNOWN);
452    jump_if_true_fork(iff, default_dest, NullTableIndex);
453  }
454
455  // Create an ideal node JumpTable that has projections
456  // of all possible ranges for a switch statement
457  // The key_val input must be converted to a pointer offset and scaled.
458  // Compare Parse::array_addressing above.
459#ifdef _LP64
460  // Clean the 32-bit int into a real 64-bit offset.
461  // Otherwise, the jint value 0 might turn into an offset of 0x0800000000.
462  const TypeLong* lkeytype = TypeLong::make(CONST64(0), num_cases-1, Type::WidenMin);
463  key_val       = _gvn.transform( new ConvI2LNode(key_val, lkeytype) );
464#endif
465  // Shift the value by wordsize so we have an index into the table, rather
466  // than a switch value
467  Node *shiftWord = _gvn.MakeConX(wordSize);
468  key_val = _gvn.transform( new MulXNode( key_val, shiftWord));
469
470  // Create the JumpNode
471  Node* jtn = _gvn.transform( new JumpNode(control(), key_val, num_cases) );
472
473  // These are the switch destinations hanging off the jumpnode
474  int i = 0;
475  for (SwitchRange* r = lo; r <= hi; r++) {
476    for (int64_t j = r->lo(); j <= r->hi(); j++, i++) {
477      Node* input = _gvn.transform(new JumpProjNode(jtn, i, r->dest(), (int)(j - lowval)));
478      {
479        PreserveJVMState pjvms(this);
480        set_control(input);
481        jump_if_always_fork(r->dest(), r->table_index());
482      }
483    }
484  }
485  assert(i == num_cases, "miscount of cases");
486  stop_and_kill_map();  // no more uses for this JVMS
487  return true;
488}
489
490//----------------------------jump_switch_ranges-------------------------------
491void Parse::jump_switch_ranges(Node* key_val, SwitchRange *lo, SwitchRange *hi, int switch_depth) {
492  Block* switch_block = block();
493
494  if (switch_depth == 0) {
495    // Do special processing for the top-level call.
496    assert(lo->lo() == min_jint, "initial range must exhaust Type::INT");
497    assert(hi->hi() == max_jint, "initial range must exhaust Type::INT");
498
499    // Decrement pred-numbers for the unique set of nodes.
500#ifdef ASSERT
501    // Ensure that the block's successors are a (duplicate-free) set.
502    int successors_counted = 0;  // block occurrences in [hi..lo]
503    int unique_successors = switch_block->num_successors();
504    for (int i = 0; i < unique_successors; i++) {
505      Block* target = switch_block->successor_at(i);
506
507      // Check that the set of successors is the same in both places.
508      int successors_found = 0;
509      for (SwitchRange* p = lo; p <= hi; p++) {
510        if (p->dest() == target->start())  successors_found++;
511      }
512      assert(successors_found > 0, "successor must be known");
513      successors_counted += successors_found;
514    }
515    assert(successors_counted == (hi-lo)+1, "no unexpected successors");
516#endif
517
518    // Maybe prune the inputs, based on the type of key_val.
519    jint min_val = min_jint;
520    jint max_val = max_jint;
521    const TypeInt* ti = key_val->bottom_type()->isa_int();
522    if (ti != NULL) {
523      min_val = ti->_lo;
524      max_val = ti->_hi;
525      assert(min_val <= max_val, "invalid int type");
526    }
527    while (lo->hi() < min_val)  lo++;
528    if (lo->lo() < min_val)  lo->setRange(min_val, lo->hi(), lo->dest(), lo->table_index());
529    while (hi->lo() > max_val)  hi--;
530    if (hi->hi() > max_val)  hi->setRange(hi->lo(), max_val, hi->dest(), hi->table_index());
531  }
532
533#ifndef PRODUCT
534  if (switch_depth == 0) {
535    _max_switch_depth = 0;
536    _est_switch_depth = log2_intptr((hi-lo+1)-1)+1;
537  }
538#endif
539
540  assert(lo <= hi, "must be a non-empty set of ranges");
541  if (lo == hi) {
542    jump_if_always_fork(lo->dest(), lo->table_index());
543  } else {
544    assert(lo->hi() == (lo+1)->lo()-1, "contiguous ranges");
545    assert(hi->lo() == (hi-1)->hi()+1, "contiguous ranges");
546
547    if (create_jump_tables(key_val, lo, hi)) return;
548
549    int nr = hi - lo + 1;
550
551    SwitchRange* mid = lo + nr/2;
552    // if there is an easy choice, pivot at a singleton:
553    if (nr > 3 && !mid->is_singleton() && (mid-1)->is_singleton())  mid--;
554
555    assert(lo < mid && mid <= hi, "good pivot choice");
556    assert(nr != 2 || mid == hi,   "should pick higher of 2");
557    assert(nr != 3 || mid == hi-1, "should pick middle of 3");
558
559    Node *test_val = _gvn.intcon(mid->lo());
560
561    if (mid->is_singleton()) {
562      IfNode *iff_ne = jump_if_fork_int(key_val, test_val, BoolTest::ne);
563      jump_if_false_fork(iff_ne, mid->dest(), mid->table_index());
564
565      // Special Case:  If there are exactly three ranges, and the high
566      // and low range each go to the same place, omit the "gt" test,
567      // since it will not discriminate anything.
568      bool eq_test_only = (hi == lo+2 && hi->dest() == lo->dest());
569      if (eq_test_only) {
570        assert(mid == hi-1, "");
571      }
572
573      // if there is a higher range, test for it and process it:
574      if (mid < hi && !eq_test_only) {
575        // two comparisons of same values--should enable 1 test for 2 branches
576        // Use BoolTest::le instead of BoolTest::gt
577        IfNode *iff_le  = jump_if_fork_int(key_val, test_val, BoolTest::le);
578        Node   *iftrue  = _gvn.transform( new IfTrueNode(iff_le) );
579        Node   *iffalse = _gvn.transform( new IfFalseNode(iff_le) );
580        { PreserveJVMState pjvms(this);
581          set_control(iffalse);
582          jump_switch_ranges(key_val, mid+1, hi, switch_depth+1);
583        }
584        set_control(iftrue);
585      }
586
587    } else {
588      // mid is a range, not a singleton, so treat mid..hi as a unit
589      IfNode *iff_ge = jump_if_fork_int(key_val, test_val, BoolTest::ge);
590
591      // if there is a higher range, test for it and process it:
592      if (mid == hi) {
593        jump_if_true_fork(iff_ge, mid->dest(), mid->table_index());
594      } else {
595        Node *iftrue  = _gvn.transform( new IfTrueNode(iff_ge) );
596        Node *iffalse = _gvn.transform( new IfFalseNode(iff_ge) );
597        { PreserveJVMState pjvms(this);
598          set_control(iftrue);
599          jump_switch_ranges(key_val, mid, hi, switch_depth+1);
600        }
601        set_control(iffalse);
602      }
603    }
604
605    // in any case, process the lower range
606    jump_switch_ranges(key_val, lo, mid-1, switch_depth+1);
607  }
608
609  // Decrease pred_count for each successor after all is done.
610  if (switch_depth == 0) {
611    int unique_successors = switch_block->num_successors();
612    for (int i = 0; i < unique_successors; i++) {
613      Block* target = switch_block->successor_at(i);
614      // Throw away the pre-allocated path for each unique successor.
615      target->next_path_num();
616    }
617  }
618
619#ifndef PRODUCT
620  _max_switch_depth = MAX2(switch_depth, _max_switch_depth);
621  if (TraceOptoParse && Verbose && WizardMode && switch_depth == 0) {
622    SwitchRange* r;
623    int nsing = 0;
624    for( r = lo; r <= hi; r++ ) {
625      if( r->is_singleton() )  nsing++;
626    }
627    tty->print(">>> ");
628    _method->print_short_name();
629    tty->print_cr(" switch decision tree");
630    tty->print_cr("    %d ranges (%d singletons), max_depth=%d, est_depth=%d",
631                  (int) (hi-lo+1), nsing, _max_switch_depth, _est_switch_depth);
632    if (_max_switch_depth > _est_switch_depth) {
633      tty->print_cr("******** BAD SWITCH DEPTH ********");
634    }
635    tty->print("   ");
636    for( r = lo; r <= hi; r++ ) {
637      r->print();
638    }
639    tty->cr();
640  }
641#endif
642}
643
644void Parse::modf() {
645  Node *f2 = pop();
646  Node *f1 = pop();
647  Node* c = make_runtime_call(RC_LEAF, OptoRuntime::modf_Type(),
648                              CAST_FROM_FN_PTR(address, SharedRuntime::frem),
649                              "frem", NULL, //no memory effects
650                              f1, f2);
651  Node* res = _gvn.transform(new ProjNode(c, TypeFunc::Parms + 0));
652
653  push(res);
654}
655
656void Parse::modd() {
657  Node *d2 = pop_pair();
658  Node *d1 = pop_pair();
659  Node* c = make_runtime_call(RC_LEAF, OptoRuntime::Math_DD_D_Type(),
660                              CAST_FROM_FN_PTR(address, SharedRuntime::drem),
661                              "drem", NULL, //no memory effects
662                              d1, top(), d2, top());
663  Node* res_d   = _gvn.transform(new ProjNode(c, TypeFunc::Parms + 0));
664
665#ifdef ASSERT
666  Node* res_top = _gvn.transform(new ProjNode(c, TypeFunc::Parms + 1));
667  assert(res_top == top(), "second value must be top");
668#endif
669
670  push_pair(res_d);
671}
672
673void Parse::l2f() {
674  Node* f2 = pop();
675  Node* f1 = pop();
676  Node* c = make_runtime_call(RC_LEAF, OptoRuntime::l2f_Type(),
677                              CAST_FROM_FN_PTR(address, SharedRuntime::l2f),
678                              "l2f", NULL, //no memory effects
679                              f1, f2);
680  Node* res = _gvn.transform(new ProjNode(c, TypeFunc::Parms + 0));
681
682  push(res);
683}
684
685void Parse::do_irem() {
686  // Must keep both values on the expression-stack during null-check
687  zero_check_int(peek());
688  // Compile-time detect of null-exception?
689  if (stopped())  return;
690
691  Node* b = pop();
692  Node* a = pop();
693
694  const Type *t = _gvn.type(b);
695  if (t != Type::TOP) {
696    const TypeInt *ti = t->is_int();
697    if (ti->is_con()) {
698      int divisor = ti->get_con();
699      // check for positive power of 2
700      if (divisor > 0 &&
701          (divisor & ~(divisor-1)) == divisor) {
702        // yes !
703        Node *mask = _gvn.intcon((divisor - 1));
704        // Sigh, must handle negative dividends
705        Node *zero = _gvn.intcon(0);
706        IfNode *ifff = jump_if_fork_int(a, zero, BoolTest::lt);
707        Node *iff = _gvn.transform( new IfFalseNode(ifff) );
708        Node *ift = _gvn.transform( new IfTrueNode (ifff) );
709        Node *reg = jump_if_join(ift, iff);
710        Node *phi = PhiNode::make(reg, NULL, TypeInt::INT);
711        // Negative path; negate/and/negate
712        Node *neg = _gvn.transform( new SubINode(zero, a) );
713        Node *andn= _gvn.transform( new AndINode(neg, mask) );
714        Node *negn= _gvn.transform( new SubINode(zero, andn) );
715        phi->init_req(1, negn);
716        // Fast positive case
717        Node *andx = _gvn.transform( new AndINode(a, mask) );
718        phi->init_req(2, andx);
719        // Push the merge
720        push( _gvn.transform(phi) );
721        return;
722      }
723    }
724  }
725  // Default case
726  push( _gvn.transform( new ModINode(control(),a,b) ) );
727}
728
729// Handle jsr and jsr_w bytecode
730void Parse::do_jsr() {
731  assert(bc() == Bytecodes::_jsr || bc() == Bytecodes::_jsr_w, "wrong bytecode");
732
733  // Store information about current state, tagged with new _jsr_bci
734  int return_bci = iter().next_bci();
735  int jsr_bci    = (bc() == Bytecodes::_jsr) ? iter().get_dest() : iter().get_far_dest();
736
737  // Update method data
738  profile_taken_branch(jsr_bci);
739
740  // The way we do things now, there is only one successor block
741  // for the jsr, because the target code is cloned by ciTypeFlow.
742  Block* target = successor_for_bci(jsr_bci);
743
744  // What got pushed?
745  const Type* ret_addr = target->peek();
746  assert(ret_addr->singleton(), "must be a constant (cloned jsr body)");
747
748  // Effect on jsr on stack
749  push(_gvn.makecon(ret_addr));
750
751  // Flow to the jsr.
752  merge(jsr_bci);
753}
754
755// Handle ret bytecode
756void Parse::do_ret() {
757  // Find to whom we return.
758  assert(block()->num_successors() == 1, "a ret can only go one place now");
759  Block* target = block()->successor_at(0);
760  assert(!target->is_ready(), "our arrival must be expected");
761  profile_ret(target->flow()->start());
762  int pnum = target->next_path_num();
763  merge_common(target, pnum);
764}
765
766//--------------------------dynamic_branch_prediction--------------------------
767// Try to gather dynamic branch prediction behavior.  Return a probability
768// of the branch being taken and set the "cnt" field.  Returns a -1.0
769// if we need to use static prediction for some reason.
770float Parse::dynamic_branch_prediction(float &cnt) {
771  ResourceMark rm;
772
773  cnt  = COUNT_UNKNOWN;
774
775  // Use MethodData information if it is available
776  // FIXME: free the ProfileData structure
777  ciMethodData* methodData = method()->method_data();
778  if (!methodData->is_mature())  return PROB_UNKNOWN;
779  ciProfileData* data = methodData->bci_to_data(bci());
780  if (!data->is_JumpData())  return PROB_UNKNOWN;
781
782  // get taken and not taken values
783  int     taken = data->as_JumpData()->taken();
784  int not_taken = 0;
785  if (data->is_BranchData()) {
786    not_taken = data->as_BranchData()->not_taken();
787  }
788
789  // scale the counts to be commensurate with invocation counts:
790  taken = method()->scale_count(taken);
791  not_taken = method()->scale_count(not_taken);
792
793  // Give up if too few (or too many, in which case the sum will overflow) counts to be meaningful.
794  // We also check that individual counters are positive first, overwise the sum can become positive.
795  if (taken < 0 || not_taken < 0 || taken + not_taken < 40) {
796    if (C->log() != NULL) {
797      C->log()->elem("branch target_bci='%d' taken='%d' not_taken='%d'", iter().get_dest(), taken, not_taken);
798    }
799    return PROB_UNKNOWN;
800  }
801
802  // Compute frequency that we arrive here
803  float sum = taken + not_taken;
804  // Adjust, if this block is a cloned private block but the
805  // Jump counts are shared.  Taken the private counts for
806  // just this path instead of the shared counts.
807  if( block()->count() > 0 )
808    sum = block()->count();
809  cnt = sum / FreqCountInvocations;
810
811  // Pin probability to sane limits
812  float prob;
813  if( !taken )
814    prob = (0+PROB_MIN) / 2;
815  else if( !not_taken )
816    prob = (1+PROB_MAX) / 2;
817  else {                         // Compute probability of true path
818    prob = (float)taken / (float)(taken + not_taken);
819    if (prob > PROB_MAX)  prob = PROB_MAX;
820    if (prob < PROB_MIN)   prob = PROB_MIN;
821  }
822
823  assert((cnt > 0.0f) && (prob > 0.0f),
824         "Bad frequency assignment in if");
825
826  if (C->log() != NULL) {
827    const char* prob_str = NULL;
828    if (prob >= PROB_MAX)  prob_str = (prob == PROB_MAX) ? "max" : "always";
829    if (prob <= PROB_MIN)  prob_str = (prob == PROB_MIN) ? "min" : "never";
830    char prob_str_buf[30];
831    if (prob_str == NULL) {
832      sprintf(prob_str_buf, "%g", prob);
833      prob_str = prob_str_buf;
834    }
835    C->log()->elem("branch target_bci='%d' taken='%d' not_taken='%d' cnt='%g' prob='%s'",
836                   iter().get_dest(), taken, not_taken, cnt, prob_str);
837  }
838  return prob;
839}
840
841//-----------------------------branch_prediction-------------------------------
842float Parse::branch_prediction(float& cnt,
843                               BoolTest::mask btest,
844                               int target_bci) {
845  float prob = dynamic_branch_prediction(cnt);
846  // If prob is unknown, switch to static prediction
847  if (prob != PROB_UNKNOWN)  return prob;
848
849  prob = PROB_FAIR;                   // Set default value
850  if (btest == BoolTest::eq)          // Exactly equal test?
851    prob = PROB_STATIC_INFREQUENT;    // Assume its relatively infrequent
852  else if (btest == BoolTest::ne)
853    prob = PROB_STATIC_FREQUENT;      // Assume its relatively frequent
854
855  // If this is a conditional test guarding a backwards branch,
856  // assume its a loop-back edge.  Make it a likely taken branch.
857  if (target_bci < bci()) {
858    if (is_osr_parse()) {    // Could be a hot OSR'd loop; force deopt
859      // Since it's an OSR, we probably have profile data, but since
860      // branch_prediction returned PROB_UNKNOWN, the counts are too small.
861      // Let's make a special check here for completely zero counts.
862      ciMethodData* methodData = method()->method_data();
863      if (!methodData->is_empty()) {
864        ciProfileData* data = methodData->bci_to_data(bci());
865        // Only stop for truly zero counts, which mean an unknown part
866        // of the OSR-ed method, and we want to deopt to gather more stats.
867        // If you have ANY counts, then this loop is simply 'cold' relative
868        // to the OSR loop.
869        if (data->as_BranchData()->taken() +
870            data->as_BranchData()->not_taken() == 0 ) {
871          // This is the only way to return PROB_UNKNOWN:
872          return PROB_UNKNOWN;
873        }
874      }
875    }
876    prob = PROB_STATIC_FREQUENT;     // Likely to take backwards branch
877  }
878
879  assert(prob != PROB_UNKNOWN, "must have some guess at this point");
880  return prob;
881}
882
883// The magic constants are chosen so as to match the output of
884// branch_prediction() when the profile reports a zero taken count.
885// It is important to distinguish zero counts unambiguously, because
886// some branches (e.g., _213_javac.Assembler.eliminate) validly produce
887// very small but nonzero probabilities, which if confused with zero
888// counts would keep the program recompiling indefinitely.
889bool Parse::seems_never_taken(float prob) {
890  return prob < PROB_MIN;
891}
892
893// True if the comparison seems to be the kind that will not change its
894// statistics from true to false.  See comments in adjust_map_after_if.
895// This question is only asked along paths which are already
896// classifed as untaken (by seems_never_taken), so really,
897// if a path is never taken, its controlling comparison is
898// already acting in a stable fashion.  If the comparison
899// seems stable, we will put an expensive uncommon trap
900// on the untaken path.
901bool Parse::seems_stable_comparison(BoolTest::mask btest, Node* cmp) {
902  if (C->too_many_traps(method(), bci(), Deoptimization::Reason_unstable_if)) {
903    return false;
904  }
905  return true;
906}
907
908//-------------------------------repush_if_args--------------------------------
909// Push arguments of an "if" bytecode back onto the stack by adjusting _sp.
910inline int Parse::repush_if_args() {
911#ifndef PRODUCT
912  if (PrintOpto && WizardMode) {
913    tty->print("defending against excessive implicit null exceptions on %s @%d in ",
914               Bytecodes::name(iter().cur_bc()), iter().cur_bci());
915    method()->print_name(); tty->cr();
916  }
917#endif
918  int bc_depth = - Bytecodes::depth(iter().cur_bc());
919  assert(bc_depth == 1 || bc_depth == 2, "only two kinds of branches");
920  DEBUG_ONLY(sync_jvms());   // argument(n) requires a synced jvms
921  assert(argument(0) != NULL, "must exist");
922  assert(bc_depth == 1 || argument(1) != NULL, "two must exist");
923  inc_sp(bc_depth);
924  return bc_depth;
925}
926
927//----------------------------------do_ifnull----------------------------------
928void Parse::do_ifnull(BoolTest::mask btest, Node *c) {
929  int target_bci = iter().get_dest();
930
931  Block* branch_block = successor_for_bci(target_bci);
932  Block* next_block   = successor_for_bci(iter().next_bci());
933
934  float cnt;
935  float prob = branch_prediction(cnt, btest, target_bci);
936  if (prob == PROB_UNKNOWN) {
937    // (An earlier version of do_ifnull omitted this trap for OSR methods.)
938#ifndef PRODUCT
939    if (PrintOpto && Verbose)
940      tty->print_cr("Never-taken edge stops compilation at bci %d",bci());
941#endif
942    repush_if_args(); // to gather stats on loop
943    // We need to mark this branch as taken so that if we recompile we will
944    // see that it is possible. In the tiered system the interpreter doesn't
945    // do profiling and by the time we get to the lower tier from the interpreter
946    // the path may be cold again. Make sure it doesn't look untaken
947    profile_taken_branch(target_bci, !ProfileInterpreter);
948    uncommon_trap(Deoptimization::Reason_unreached,
949                  Deoptimization::Action_reinterpret,
950                  NULL, "cold");
951    if (C->eliminate_boxing()) {
952      // Mark the successor blocks as parsed
953      branch_block->next_path_num();
954      next_block->next_path_num();
955    }
956    return;
957  }
958
959  explicit_null_checks_inserted++;
960
961  // Generate real control flow
962  Node   *tst = _gvn.transform( new BoolNode( c, btest ) );
963
964  // Sanity check the probability value
965  assert(prob > 0.0f,"Bad probability in Parser");
966 // Need xform to put node in hash table
967  IfNode *iff = create_and_xform_if( control(), tst, prob, cnt );
968  assert(iff->_prob > 0.0f,"Optimizer made bad probability in parser");
969  // True branch
970  { PreserveJVMState pjvms(this);
971    Node* iftrue  = _gvn.transform( new IfTrueNode (iff) );
972    set_control(iftrue);
973
974    if (stopped()) {            // Path is dead?
975      explicit_null_checks_elided++;
976      if (C->eliminate_boxing()) {
977        // Mark the successor block as parsed
978        branch_block->next_path_num();
979      }
980    } else {                    // Path is live.
981      // Update method data
982      profile_taken_branch(target_bci);
983      adjust_map_after_if(btest, c, prob, branch_block, next_block);
984      if (!stopped()) {
985        merge(target_bci);
986      }
987    }
988  }
989
990  // False branch
991  Node* iffalse = _gvn.transform( new IfFalseNode(iff) );
992  set_control(iffalse);
993
994  if (stopped()) {              // Path is dead?
995    explicit_null_checks_elided++;
996    if (C->eliminate_boxing()) {
997      // Mark the successor block as parsed
998      next_block->next_path_num();
999    }
1000  } else  {                     // Path is live.
1001    // Update method data
1002    profile_not_taken_branch();
1003    adjust_map_after_if(BoolTest(btest).negate(), c, 1.0-prob,
1004                        next_block, branch_block);
1005  }
1006}
1007
1008//------------------------------------do_if------------------------------------
1009void Parse::do_if(BoolTest::mask btest, Node* c) {
1010  int target_bci = iter().get_dest();
1011
1012  Block* branch_block = successor_for_bci(target_bci);
1013  Block* next_block   = successor_for_bci(iter().next_bci());
1014
1015  float cnt;
1016  float prob = branch_prediction(cnt, btest, target_bci);
1017  float untaken_prob = 1.0 - prob;
1018
1019  if (prob == PROB_UNKNOWN) {
1020#ifndef PRODUCT
1021    if (PrintOpto && Verbose)
1022      tty->print_cr("Never-taken edge stops compilation at bci %d",bci());
1023#endif
1024    repush_if_args(); // to gather stats on loop
1025    // We need to mark this branch as taken so that if we recompile we will
1026    // see that it is possible. In the tiered system the interpreter doesn't
1027    // do profiling and by the time we get to the lower tier from the interpreter
1028    // the path may be cold again. Make sure it doesn't look untaken
1029    profile_taken_branch(target_bci, !ProfileInterpreter);
1030    uncommon_trap(Deoptimization::Reason_unreached,
1031                  Deoptimization::Action_reinterpret,
1032                  NULL, "cold");
1033    if (C->eliminate_boxing()) {
1034      // Mark the successor blocks as parsed
1035      branch_block->next_path_num();
1036      next_block->next_path_num();
1037    }
1038    return;
1039  }
1040
1041  // Sanity check the probability value
1042  assert(0.0f < prob && prob < 1.0f,"Bad probability in Parser");
1043
1044  bool taken_if_true = true;
1045  // Convert BoolTest to canonical form:
1046  if (!BoolTest(btest).is_canonical()) {
1047    btest         = BoolTest(btest).negate();
1048    taken_if_true = false;
1049    // prob is NOT updated here; it remains the probability of the taken
1050    // path (as opposed to the prob of the path guarded by an 'IfTrueNode').
1051  }
1052  assert(btest != BoolTest::eq, "!= is the only canonical exact test");
1053
1054  Node* tst0 = new BoolNode(c, btest);
1055  Node* tst = _gvn.transform(tst0);
1056  BoolTest::mask taken_btest   = BoolTest::illegal;
1057  BoolTest::mask untaken_btest = BoolTest::illegal;
1058
1059  if (tst->is_Bool()) {
1060    // Refresh c from the transformed bool node, since it may be
1061    // simpler than the original c.  Also re-canonicalize btest.
1062    // This wins when (Bool ne (Conv2B p) 0) => (Bool ne (CmpP p NULL)).
1063    // That can arise from statements like: if (x instanceof C) ...
1064    if (tst != tst0) {
1065      // Canonicalize one more time since transform can change it.
1066      btest = tst->as_Bool()->_test._test;
1067      if (!BoolTest(btest).is_canonical()) {
1068        // Reverse edges one more time...
1069        tst   = _gvn.transform( tst->as_Bool()->negate(&_gvn) );
1070        btest = tst->as_Bool()->_test._test;
1071        assert(BoolTest(btest).is_canonical(), "sanity");
1072        taken_if_true = !taken_if_true;
1073      }
1074      c = tst->in(1);
1075    }
1076    BoolTest::mask neg_btest = BoolTest(btest).negate();
1077    taken_btest   = taken_if_true ?     btest : neg_btest;
1078    untaken_btest = taken_if_true ? neg_btest :     btest;
1079  }
1080
1081  // Generate real control flow
1082  float true_prob = (taken_if_true ? prob : untaken_prob);
1083  IfNode* iff = create_and_map_if(control(), tst, true_prob, cnt);
1084  assert(iff->_prob > 0.0f,"Optimizer made bad probability in parser");
1085  Node* taken_branch   = new IfTrueNode(iff);
1086  Node* untaken_branch = new IfFalseNode(iff);
1087  if (!taken_if_true) {  // Finish conversion to canonical form
1088    Node* tmp      = taken_branch;
1089    taken_branch   = untaken_branch;
1090    untaken_branch = tmp;
1091  }
1092
1093  // Branch is taken:
1094  { PreserveJVMState pjvms(this);
1095    taken_branch = _gvn.transform(taken_branch);
1096    set_control(taken_branch);
1097
1098    if (stopped()) {
1099      if (C->eliminate_boxing()) {
1100        // Mark the successor block as parsed
1101        branch_block->next_path_num();
1102      }
1103    } else {
1104      // Update method data
1105      profile_taken_branch(target_bci);
1106      adjust_map_after_if(taken_btest, c, prob, branch_block, next_block);
1107      if (!stopped()) {
1108        merge(target_bci);
1109      }
1110    }
1111  }
1112
1113  untaken_branch = _gvn.transform(untaken_branch);
1114  set_control(untaken_branch);
1115
1116  // Branch not taken.
1117  if (stopped()) {
1118    if (C->eliminate_boxing()) {
1119      // Mark the successor block as parsed
1120      next_block->next_path_num();
1121    }
1122  } else {
1123    // Update method data
1124    profile_not_taken_branch();
1125    adjust_map_after_if(untaken_btest, c, untaken_prob,
1126                        next_block, branch_block);
1127  }
1128}
1129
1130//----------------------------adjust_map_after_if------------------------------
1131// Adjust the JVM state to reflect the result of taking this path.
1132// Basically, it means inspecting the CmpNode controlling this
1133// branch, seeing how it constrains a tested value, and then
1134// deciding if it's worth our while to encode this constraint
1135// as graph nodes in the current abstract interpretation map.
1136void Parse::adjust_map_after_if(BoolTest::mask btest, Node* c, float prob,
1137                                Block* path, Block* other_path) {
1138  if (stopped() || !c->is_Cmp() || btest == BoolTest::illegal)
1139    return;                             // nothing to do
1140
1141  bool is_fallthrough = (path == successor_for_bci(iter().next_bci()));
1142
1143  if (seems_never_taken(prob) && seems_stable_comparison(btest, c)) {
1144    repush_if_args();
1145    uncommon_trap(Deoptimization::Reason_unstable_if,
1146                  Deoptimization::Action_reinterpret,
1147                  NULL,
1148                  (is_fallthrough ? "taken always" : "taken never"));
1149    return;
1150  }
1151
1152  Node* val = c->in(1);
1153  Node* con = c->in(2);
1154  const Type* tcon = _gvn.type(con);
1155  const Type* tval = _gvn.type(val);
1156  bool have_con = tcon->singleton();
1157  if (tval->singleton()) {
1158    if (!have_con) {
1159      // Swap, so constant is in con.
1160      con  = val;
1161      tcon = tval;
1162      val  = c->in(2);
1163      tval = _gvn.type(val);
1164      btest = BoolTest(btest).commute();
1165      have_con = true;
1166    } else {
1167      // Do we have two constants?  Then leave well enough alone.
1168      have_con = false;
1169    }
1170  }
1171  if (!have_con)                        // remaining adjustments need a con
1172    return;
1173
1174  sharpen_type_after_if(btest, con, tcon, val, tval);
1175}
1176
1177
1178static Node* extract_obj_from_klass_load(PhaseGVN* gvn, Node* n) {
1179  Node* ldk;
1180  if (n->is_DecodeNKlass()) {
1181    if (n->in(1)->Opcode() != Op_LoadNKlass) {
1182      return NULL;
1183    } else {
1184      ldk = n->in(1);
1185    }
1186  } else if (n->Opcode() != Op_LoadKlass) {
1187    return NULL;
1188  } else {
1189    ldk = n;
1190  }
1191  assert(ldk != NULL && ldk->is_Load(), "should have found a LoadKlass or LoadNKlass node");
1192
1193  Node* adr = ldk->in(MemNode::Address);
1194  intptr_t off = 0;
1195  Node* obj = AddPNode::Ideal_base_and_offset(adr, gvn, off);
1196  if (obj == NULL || off != oopDesc::klass_offset_in_bytes()) // loading oopDesc::_klass?
1197    return NULL;
1198  const TypePtr* tp = gvn->type(obj)->is_ptr();
1199  if (tp == NULL || !(tp->isa_instptr() || tp->isa_aryptr())) // is obj a Java object ptr?
1200    return NULL;
1201
1202  return obj;
1203}
1204
1205void Parse::sharpen_type_after_if(BoolTest::mask btest,
1206                                  Node* con, const Type* tcon,
1207                                  Node* val, const Type* tval) {
1208  // Look for opportunities to sharpen the type of a node
1209  // whose klass is compared with a constant klass.
1210  if (btest == BoolTest::eq && tcon->isa_klassptr()) {
1211    Node* obj = extract_obj_from_klass_load(&_gvn, val);
1212    const TypeOopPtr* con_type = tcon->isa_klassptr()->as_instance_type();
1213    if (obj != NULL && (con_type->isa_instptr() || con_type->isa_aryptr())) {
1214       // Found:
1215       //   Bool(CmpP(LoadKlass(obj._klass), ConP(Foo.klass)), [eq])
1216       // or the narrowOop equivalent.
1217       const Type* obj_type = _gvn.type(obj);
1218       const TypeOopPtr* tboth = obj_type->join_speculative(con_type)->isa_oopptr();
1219       if (tboth != NULL && tboth->klass_is_exact() && tboth != obj_type &&
1220           tboth->higher_equal(obj_type)) {
1221          // obj has to be of the exact type Foo if the CmpP succeeds.
1222          int obj_in_map = map()->find_edge(obj);
1223          JVMState* jvms = this->jvms();
1224          if (obj_in_map >= 0 &&
1225              (jvms->is_loc(obj_in_map) || jvms->is_stk(obj_in_map))) {
1226            TypeNode* ccast = new CheckCastPPNode(control(), obj, tboth);
1227            const Type* tcc = ccast->as_Type()->type();
1228            assert(tcc != obj_type && tcc->higher_equal(obj_type), "must improve");
1229            // Delay transform() call to allow recovery of pre-cast value
1230            // at the control merge.
1231            _gvn.set_type_bottom(ccast);
1232            record_for_igvn(ccast);
1233            // Here's the payoff.
1234            replace_in_map(obj, ccast);
1235          }
1236       }
1237    }
1238  }
1239
1240  int val_in_map = map()->find_edge(val);
1241  if (val_in_map < 0)  return;          // replace_in_map would be useless
1242  {
1243    JVMState* jvms = this->jvms();
1244    if (!(jvms->is_loc(val_in_map) ||
1245          jvms->is_stk(val_in_map)))
1246      return;                           // again, it would be useless
1247  }
1248
1249  // Check for a comparison to a constant, and "know" that the compared
1250  // value is constrained on this path.
1251  assert(tcon->singleton(), "");
1252  ConstraintCastNode* ccast = NULL;
1253  Node* cast = NULL;
1254
1255  switch (btest) {
1256  case BoolTest::eq:                    // Constant test?
1257    {
1258      const Type* tboth = tcon->join_speculative(tval);
1259      if (tboth == tval)  break;        // Nothing to gain.
1260      if (tcon->isa_int()) {
1261        ccast = new CastIINode(val, tboth);
1262      } else if (tcon == TypePtr::NULL_PTR) {
1263        // Cast to null, but keep the pointer identity temporarily live.
1264        ccast = new CastPPNode(val, tboth);
1265      } else {
1266        const TypeF* tf = tcon->isa_float_constant();
1267        const TypeD* td = tcon->isa_double_constant();
1268        // Exclude tests vs float/double 0 as these could be
1269        // either +0 or -0.  Just because you are equal to +0
1270        // doesn't mean you ARE +0!
1271        // Note, following code also replaces Long and Oop values.
1272        if ((!tf || tf->_f != 0.0) &&
1273            (!td || td->_d != 0.0))
1274          cast = con;                   // Replace non-constant val by con.
1275      }
1276    }
1277    break;
1278
1279  case BoolTest::ne:
1280    if (tcon == TypePtr::NULL_PTR) {
1281      cast = cast_not_null(val, false);
1282    }
1283    break;
1284
1285  default:
1286    // (At this point we could record int range types with CastII.)
1287    break;
1288  }
1289
1290  if (ccast != NULL) {
1291    const Type* tcc = ccast->as_Type()->type();
1292    assert(tcc != tval && tcc->higher_equal(tval), "must improve");
1293    // Delay transform() call to allow recovery of pre-cast value
1294    // at the control merge.
1295    ccast->set_req(0, control());
1296    _gvn.set_type_bottom(ccast);
1297    record_for_igvn(ccast);
1298    cast = ccast;
1299  }
1300
1301  if (cast != NULL) {                   // Here's the payoff.
1302    replace_in_map(val, cast);
1303  }
1304}
1305
1306/**
1307 * Use speculative type to optimize CmpP node: if comparison is
1308 * against the low level class, cast the object to the speculative
1309 * type if any. CmpP should then go away.
1310 *
1311 * @param c  expected CmpP node
1312 * @return   result of CmpP on object casted to speculative type
1313 *
1314 */
1315Node* Parse::optimize_cmp_with_klass(Node* c) {
1316  // If this is transformed by the _gvn to a comparison with the low
1317  // level klass then we may be able to use speculation
1318  if (c->Opcode() == Op_CmpP &&
1319      (c->in(1)->Opcode() == Op_LoadKlass || c->in(1)->Opcode() == Op_DecodeNKlass) &&
1320      c->in(2)->is_Con()) {
1321    Node* load_klass = NULL;
1322    Node* decode = NULL;
1323    if (c->in(1)->Opcode() == Op_DecodeNKlass) {
1324      decode = c->in(1);
1325      load_klass = c->in(1)->in(1);
1326    } else {
1327      load_klass = c->in(1);
1328    }
1329    if (load_klass->in(2)->is_AddP()) {
1330      Node* addp = load_klass->in(2);
1331      Node* obj = addp->in(AddPNode::Address);
1332      const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
1333      if (obj_type->speculative_type_not_null() != NULL) {
1334        ciKlass* k = obj_type->speculative_type();
1335        inc_sp(2);
1336        obj = maybe_cast_profiled_obj(obj, k);
1337        dec_sp(2);
1338        // Make the CmpP use the casted obj
1339        addp = basic_plus_adr(obj, addp->in(AddPNode::Offset));
1340        load_klass = load_klass->clone();
1341        load_klass->set_req(2, addp);
1342        load_klass = _gvn.transform(load_klass);
1343        if (decode != NULL) {
1344          decode = decode->clone();
1345          decode->set_req(1, load_klass);
1346          load_klass = _gvn.transform(decode);
1347        }
1348        c = c->clone();
1349        c->set_req(1, load_klass);
1350        c = _gvn.transform(c);
1351      }
1352    }
1353  }
1354  return c;
1355}
1356
1357//------------------------------do_one_bytecode--------------------------------
1358// Parse this bytecode, and alter the Parsers JVM->Node mapping
1359void Parse::do_one_bytecode() {
1360  Node *a, *b, *c, *d;          // Handy temps
1361  BoolTest::mask btest;
1362  int i;
1363
1364  assert(!has_exceptions(), "bytecode entry state must be clear of throws");
1365
1366  if (C->check_node_count(NodeLimitFudgeFactor * 5,
1367                          "out of nodes parsing method")) {
1368    return;
1369  }
1370
1371#ifdef ASSERT
1372  // for setting breakpoints
1373  if (TraceOptoParse) {
1374    tty->print(" @");
1375    dump_bci(bci());
1376    tty->cr();
1377  }
1378#endif
1379
1380  switch (bc()) {
1381  case Bytecodes::_nop:
1382    // do nothing
1383    break;
1384  case Bytecodes::_lconst_0:
1385    push_pair(longcon(0));
1386    break;
1387
1388  case Bytecodes::_lconst_1:
1389    push_pair(longcon(1));
1390    break;
1391
1392  case Bytecodes::_fconst_0:
1393    push(zerocon(T_FLOAT));
1394    break;
1395
1396  case Bytecodes::_fconst_1:
1397    push(makecon(TypeF::ONE));
1398    break;
1399
1400  case Bytecodes::_fconst_2:
1401    push(makecon(TypeF::make(2.0f)));
1402    break;
1403
1404  case Bytecodes::_dconst_0:
1405    push_pair(zerocon(T_DOUBLE));
1406    break;
1407
1408  case Bytecodes::_dconst_1:
1409    push_pair(makecon(TypeD::ONE));
1410    break;
1411
1412  case Bytecodes::_iconst_m1:push(intcon(-1)); break;
1413  case Bytecodes::_iconst_0: push(intcon( 0)); break;
1414  case Bytecodes::_iconst_1: push(intcon( 1)); break;
1415  case Bytecodes::_iconst_2: push(intcon( 2)); break;
1416  case Bytecodes::_iconst_3: push(intcon( 3)); break;
1417  case Bytecodes::_iconst_4: push(intcon( 4)); break;
1418  case Bytecodes::_iconst_5: push(intcon( 5)); break;
1419  case Bytecodes::_bipush:   push(intcon(iter().get_constant_u1())); break;
1420  case Bytecodes::_sipush:   push(intcon(iter().get_constant_u2())); break;
1421  case Bytecodes::_aconst_null: push(null());  break;
1422  case Bytecodes::_ldc:
1423  case Bytecodes::_ldc_w:
1424  case Bytecodes::_ldc2_w:
1425    // If the constant is unresolved, run this BC once in the interpreter.
1426    {
1427      ciConstant constant = iter().get_constant();
1428      if (constant.basic_type() == T_OBJECT &&
1429          !constant.as_object()->is_loaded()) {
1430        int index = iter().get_constant_pool_index();
1431        constantTag tag = iter().get_constant_pool_tag(index);
1432        uncommon_trap(Deoptimization::make_trap_request
1433                      (Deoptimization::Reason_unloaded,
1434                       Deoptimization::Action_reinterpret,
1435                       index),
1436                      NULL, tag.internal_name());
1437        break;
1438      }
1439      assert(constant.basic_type() != T_OBJECT || constant.as_object()->is_instance(),
1440             "must be java_mirror of klass");
1441      bool pushed = push_constant(constant, true);
1442      guarantee(pushed, "must be possible to push this constant");
1443    }
1444
1445    break;
1446
1447  case Bytecodes::_aload_0:
1448    push( local(0) );
1449    break;
1450  case Bytecodes::_aload_1:
1451    push( local(1) );
1452    break;
1453  case Bytecodes::_aload_2:
1454    push( local(2) );
1455    break;
1456  case Bytecodes::_aload_3:
1457    push( local(3) );
1458    break;
1459  case Bytecodes::_aload:
1460    push( local(iter().get_index()) );
1461    break;
1462
1463  case Bytecodes::_fload_0:
1464  case Bytecodes::_iload_0:
1465    push( local(0) );
1466    break;
1467  case Bytecodes::_fload_1:
1468  case Bytecodes::_iload_1:
1469    push( local(1) );
1470    break;
1471  case Bytecodes::_fload_2:
1472  case Bytecodes::_iload_2:
1473    push( local(2) );
1474    break;
1475  case Bytecodes::_fload_3:
1476  case Bytecodes::_iload_3:
1477    push( local(3) );
1478    break;
1479  case Bytecodes::_fload:
1480  case Bytecodes::_iload:
1481    push( local(iter().get_index()) );
1482    break;
1483  case Bytecodes::_lload_0:
1484    push_pair_local( 0 );
1485    break;
1486  case Bytecodes::_lload_1:
1487    push_pair_local( 1 );
1488    break;
1489  case Bytecodes::_lload_2:
1490    push_pair_local( 2 );
1491    break;
1492  case Bytecodes::_lload_3:
1493    push_pair_local( 3 );
1494    break;
1495  case Bytecodes::_lload:
1496    push_pair_local( iter().get_index() );
1497    break;
1498
1499  case Bytecodes::_dload_0:
1500    push_pair_local(0);
1501    break;
1502  case Bytecodes::_dload_1:
1503    push_pair_local(1);
1504    break;
1505  case Bytecodes::_dload_2:
1506    push_pair_local(2);
1507    break;
1508  case Bytecodes::_dload_3:
1509    push_pair_local(3);
1510    break;
1511  case Bytecodes::_dload:
1512    push_pair_local(iter().get_index());
1513    break;
1514  case Bytecodes::_fstore_0:
1515  case Bytecodes::_istore_0:
1516  case Bytecodes::_astore_0:
1517    set_local( 0, pop() );
1518    break;
1519  case Bytecodes::_fstore_1:
1520  case Bytecodes::_istore_1:
1521  case Bytecodes::_astore_1:
1522    set_local( 1, pop() );
1523    break;
1524  case Bytecodes::_fstore_2:
1525  case Bytecodes::_istore_2:
1526  case Bytecodes::_astore_2:
1527    set_local( 2, pop() );
1528    break;
1529  case Bytecodes::_fstore_3:
1530  case Bytecodes::_istore_3:
1531  case Bytecodes::_astore_3:
1532    set_local( 3, pop() );
1533    break;
1534  case Bytecodes::_fstore:
1535  case Bytecodes::_istore:
1536  case Bytecodes::_astore:
1537    set_local( iter().get_index(), pop() );
1538    break;
1539  // long stores
1540  case Bytecodes::_lstore_0:
1541    set_pair_local( 0, pop_pair() );
1542    break;
1543  case Bytecodes::_lstore_1:
1544    set_pair_local( 1, pop_pair() );
1545    break;
1546  case Bytecodes::_lstore_2:
1547    set_pair_local( 2, pop_pair() );
1548    break;
1549  case Bytecodes::_lstore_3:
1550    set_pair_local( 3, pop_pair() );
1551    break;
1552  case Bytecodes::_lstore:
1553    set_pair_local( iter().get_index(), pop_pair() );
1554    break;
1555
1556  // double stores
1557  case Bytecodes::_dstore_0:
1558    set_pair_local( 0, dstore_rounding(pop_pair()) );
1559    break;
1560  case Bytecodes::_dstore_1:
1561    set_pair_local( 1, dstore_rounding(pop_pair()) );
1562    break;
1563  case Bytecodes::_dstore_2:
1564    set_pair_local( 2, dstore_rounding(pop_pair()) );
1565    break;
1566  case Bytecodes::_dstore_3:
1567    set_pair_local( 3, dstore_rounding(pop_pair()) );
1568    break;
1569  case Bytecodes::_dstore:
1570    set_pair_local( iter().get_index(), dstore_rounding(pop_pair()) );
1571    break;
1572
1573  case Bytecodes::_pop:  dec_sp(1);   break;
1574  case Bytecodes::_pop2: dec_sp(2);   break;
1575  case Bytecodes::_swap:
1576    a = pop();
1577    b = pop();
1578    push(a);
1579    push(b);
1580    break;
1581  case Bytecodes::_dup:
1582    a = pop();
1583    push(a);
1584    push(a);
1585    break;
1586  case Bytecodes::_dup_x1:
1587    a = pop();
1588    b = pop();
1589    push( a );
1590    push( b );
1591    push( a );
1592    break;
1593  case Bytecodes::_dup_x2:
1594    a = pop();
1595    b = pop();
1596    c = pop();
1597    push( a );
1598    push( c );
1599    push( b );
1600    push( a );
1601    break;
1602  case Bytecodes::_dup2:
1603    a = pop();
1604    b = pop();
1605    push( b );
1606    push( a );
1607    push( b );
1608    push( a );
1609    break;
1610
1611  case Bytecodes::_dup2_x1:
1612    // before: .. c, b, a
1613    // after:  .. b, a, c, b, a
1614    // not tested
1615    a = pop();
1616    b = pop();
1617    c = pop();
1618    push( b );
1619    push( a );
1620    push( c );
1621    push( b );
1622    push( a );
1623    break;
1624  case Bytecodes::_dup2_x2:
1625    // before: .. d, c, b, a
1626    // after:  .. b, a, d, c, b, a
1627    // not tested
1628    a = pop();
1629    b = pop();
1630    c = pop();
1631    d = pop();
1632    push( b );
1633    push( a );
1634    push( d );
1635    push( c );
1636    push( b );
1637    push( a );
1638    break;
1639
1640  case Bytecodes::_arraylength: {
1641    // Must do null-check with value on expression stack
1642    Node *ary = null_check(peek(), T_ARRAY);
1643    // Compile-time detect of null-exception?
1644    if (stopped())  return;
1645    a = pop();
1646    push(load_array_length(a));
1647    break;
1648  }
1649
1650  case Bytecodes::_baload: array_load(T_BYTE);   break;
1651  case Bytecodes::_caload: array_load(T_CHAR);   break;
1652  case Bytecodes::_iaload: array_load(T_INT);    break;
1653  case Bytecodes::_saload: array_load(T_SHORT);  break;
1654  case Bytecodes::_faload: array_load(T_FLOAT);  break;
1655  case Bytecodes::_aaload: array_load(T_OBJECT); break;
1656  case Bytecodes::_laload: {
1657    a = array_addressing(T_LONG, 0);
1658    if (stopped())  return;     // guaranteed null or range check
1659    dec_sp(2);                  // Pop array and index
1660    push_pair(make_load(control(), a, TypeLong::LONG, T_LONG, TypeAryPtr::LONGS, MemNode::unordered));
1661    break;
1662  }
1663  case Bytecodes::_daload: {
1664    a = array_addressing(T_DOUBLE, 0);
1665    if (stopped())  return;     // guaranteed null or range check
1666    dec_sp(2);                  // Pop array and index
1667    push_pair(make_load(control(), a, Type::DOUBLE, T_DOUBLE, TypeAryPtr::DOUBLES, MemNode::unordered));
1668    break;
1669  }
1670  case Bytecodes::_bastore: array_store(T_BYTE);  break;
1671  case Bytecodes::_castore: array_store(T_CHAR);  break;
1672  case Bytecodes::_iastore: array_store(T_INT);   break;
1673  case Bytecodes::_sastore: array_store(T_SHORT); break;
1674  case Bytecodes::_fastore: array_store(T_FLOAT); break;
1675  case Bytecodes::_aastore: {
1676    d = array_addressing(T_OBJECT, 1);
1677    if (stopped())  return;     // guaranteed null or range check
1678    array_store_check();
1679    c = pop();                  // Oop to store
1680    b = pop();                  // index (already used)
1681    a = pop();                  // the array itself
1682    const TypeOopPtr* elemtype  = _gvn.type(a)->is_aryptr()->elem()->make_oopptr();
1683    const TypeAryPtr* adr_type = TypeAryPtr::OOPS;
1684    Node* store = store_oop_to_array(control(), a, d, adr_type, c, elemtype, T_OBJECT, MemNode::release);
1685    break;
1686  }
1687  case Bytecodes::_lastore: {
1688    a = array_addressing(T_LONG, 2);
1689    if (stopped())  return;     // guaranteed null or range check
1690    c = pop_pair();
1691    dec_sp(2);                  // Pop array and index
1692    store_to_memory(control(), a, c, T_LONG, TypeAryPtr::LONGS, MemNode::unordered);
1693    break;
1694  }
1695  case Bytecodes::_dastore: {
1696    a = array_addressing(T_DOUBLE, 2);
1697    if (stopped())  return;     // guaranteed null or range check
1698    c = pop_pair();
1699    dec_sp(2);                  // Pop array and index
1700    c = dstore_rounding(c);
1701    store_to_memory(control(), a, c, T_DOUBLE, TypeAryPtr::DOUBLES, MemNode::unordered);
1702    break;
1703  }
1704  case Bytecodes::_getfield:
1705    do_getfield();
1706    break;
1707
1708  case Bytecodes::_getstatic:
1709    do_getstatic();
1710    break;
1711
1712  case Bytecodes::_putfield:
1713    do_putfield();
1714    break;
1715
1716  case Bytecodes::_putstatic:
1717    do_putstatic();
1718    break;
1719
1720  case Bytecodes::_irem:
1721    do_irem();
1722    break;
1723  case Bytecodes::_idiv:
1724    // Must keep both values on the expression-stack during null-check
1725    zero_check_int(peek());
1726    // Compile-time detect of null-exception?
1727    if (stopped())  return;
1728    b = pop();
1729    a = pop();
1730    push( _gvn.transform( new DivINode(control(),a,b) ) );
1731    break;
1732  case Bytecodes::_imul:
1733    b = pop(); a = pop();
1734    push( _gvn.transform( new MulINode(a,b) ) );
1735    break;
1736  case Bytecodes::_iadd:
1737    b = pop(); a = pop();
1738    push( _gvn.transform( new AddINode(a,b) ) );
1739    break;
1740  case Bytecodes::_ineg:
1741    a = pop();
1742    push( _gvn.transform( new SubINode(_gvn.intcon(0),a)) );
1743    break;
1744  case Bytecodes::_isub:
1745    b = pop(); a = pop();
1746    push( _gvn.transform( new SubINode(a,b) ) );
1747    break;
1748  case Bytecodes::_iand:
1749    b = pop(); a = pop();
1750    push( _gvn.transform( new AndINode(a,b) ) );
1751    break;
1752  case Bytecodes::_ior:
1753    b = pop(); a = pop();
1754    push( _gvn.transform( new OrINode(a,b) ) );
1755    break;
1756  case Bytecodes::_ixor:
1757    b = pop(); a = pop();
1758    push( _gvn.transform( new XorINode(a,b) ) );
1759    break;
1760  case Bytecodes::_ishl:
1761    b = pop(); a = pop();
1762    push( _gvn.transform( new LShiftINode(a,b) ) );
1763    break;
1764  case Bytecodes::_ishr:
1765    b = pop(); a = pop();
1766    push( _gvn.transform( new RShiftINode(a,b) ) );
1767    break;
1768  case Bytecodes::_iushr:
1769    b = pop(); a = pop();
1770    push( _gvn.transform( new URShiftINode(a,b) ) );
1771    break;
1772
1773  case Bytecodes::_fneg:
1774    a = pop();
1775    b = _gvn.transform(new NegFNode (a));
1776    push(b);
1777    break;
1778
1779  case Bytecodes::_fsub:
1780    b = pop();
1781    a = pop();
1782    c = _gvn.transform( new SubFNode(a,b) );
1783    d = precision_rounding(c);
1784    push( d );
1785    break;
1786
1787  case Bytecodes::_fadd:
1788    b = pop();
1789    a = pop();
1790    c = _gvn.transform( new AddFNode(a,b) );
1791    d = precision_rounding(c);
1792    push( d );
1793    break;
1794
1795  case Bytecodes::_fmul:
1796    b = pop();
1797    a = pop();
1798    c = _gvn.transform( new MulFNode(a,b) );
1799    d = precision_rounding(c);
1800    push( d );
1801    break;
1802
1803  case Bytecodes::_fdiv:
1804    b = pop();
1805    a = pop();
1806    c = _gvn.transform( new DivFNode(0,a,b) );
1807    d = precision_rounding(c);
1808    push( d );
1809    break;
1810
1811  case Bytecodes::_frem:
1812    if (Matcher::has_match_rule(Op_ModF)) {
1813      // Generate a ModF node.
1814      b = pop();
1815      a = pop();
1816      c = _gvn.transform( new ModFNode(0,a,b) );
1817      d = precision_rounding(c);
1818      push( d );
1819    }
1820    else {
1821      // Generate a call.
1822      modf();
1823    }
1824    break;
1825
1826  case Bytecodes::_fcmpl:
1827    b = pop();
1828    a = pop();
1829    c = _gvn.transform( new CmpF3Node( a, b));
1830    push(c);
1831    break;
1832  case Bytecodes::_fcmpg:
1833    b = pop();
1834    a = pop();
1835
1836    // Same as fcmpl but need to flip the unordered case.  Swap the inputs,
1837    // which negates the result sign except for unordered.  Flip the unordered
1838    // as well by using CmpF3 which implements unordered-lesser instead of
1839    // unordered-greater semantics.  Finally, commute the result bits.  Result
1840    // is same as using a CmpF3Greater except we did it with CmpF3 alone.
1841    c = _gvn.transform( new CmpF3Node( b, a));
1842    c = _gvn.transform( new SubINode(_gvn.intcon(0),c) );
1843    push(c);
1844    break;
1845
1846  case Bytecodes::_f2i:
1847    a = pop();
1848    push(_gvn.transform(new ConvF2INode(a)));
1849    break;
1850
1851  case Bytecodes::_d2i:
1852    a = pop_pair();
1853    b = _gvn.transform(new ConvD2INode(a));
1854    push( b );
1855    break;
1856
1857  case Bytecodes::_f2d:
1858    a = pop();
1859    b = _gvn.transform( new ConvF2DNode(a));
1860    push_pair( b );
1861    break;
1862
1863  case Bytecodes::_d2f:
1864    a = pop_pair();
1865    b = _gvn.transform( new ConvD2FNode(a));
1866    // This breaks _227_mtrt (speed & correctness) and _222_mpegaudio (speed)
1867    //b = _gvn.transform(new RoundFloatNode(0, b) );
1868    push( b );
1869    break;
1870
1871  case Bytecodes::_l2f:
1872    if (Matcher::convL2FSupported()) {
1873      a = pop_pair();
1874      b = _gvn.transform( new ConvL2FNode(a));
1875      // For i486.ad, FILD doesn't restrict precision to 24 or 53 bits.
1876      // Rather than storing the result into an FP register then pushing
1877      // out to memory to round, the machine instruction that implements
1878      // ConvL2D is responsible for rounding.
1879      // c = precision_rounding(b);
1880      c = _gvn.transform(b);
1881      push(c);
1882    } else {
1883      l2f();
1884    }
1885    break;
1886
1887  case Bytecodes::_l2d:
1888    a = pop_pair();
1889    b = _gvn.transform( new ConvL2DNode(a));
1890    // For i486.ad, rounding is always necessary (see _l2f above).
1891    // c = dprecision_rounding(b);
1892    c = _gvn.transform(b);
1893    push_pair(c);
1894    break;
1895
1896  case Bytecodes::_f2l:
1897    a = pop();
1898    b = _gvn.transform( new ConvF2LNode(a));
1899    push_pair(b);
1900    break;
1901
1902  case Bytecodes::_d2l:
1903    a = pop_pair();
1904    b = _gvn.transform( new ConvD2LNode(a));
1905    push_pair(b);
1906    break;
1907
1908  case Bytecodes::_dsub:
1909    b = pop_pair();
1910    a = pop_pair();
1911    c = _gvn.transform( new SubDNode(a,b) );
1912    d = dprecision_rounding(c);
1913    push_pair( d );
1914    break;
1915
1916  case Bytecodes::_dadd:
1917    b = pop_pair();
1918    a = pop_pair();
1919    c = _gvn.transform( new AddDNode(a,b) );
1920    d = dprecision_rounding(c);
1921    push_pair( d );
1922    break;
1923
1924  case Bytecodes::_dmul:
1925    b = pop_pair();
1926    a = pop_pair();
1927    c = _gvn.transform( new MulDNode(a,b) );
1928    d = dprecision_rounding(c);
1929    push_pair( d );
1930    break;
1931
1932  case Bytecodes::_ddiv:
1933    b = pop_pair();
1934    a = pop_pair();
1935    c = _gvn.transform( new DivDNode(0,a,b) );
1936    d = dprecision_rounding(c);
1937    push_pair( d );
1938    break;
1939
1940  case Bytecodes::_dneg:
1941    a = pop_pair();
1942    b = _gvn.transform(new NegDNode (a));
1943    push_pair(b);
1944    break;
1945
1946  case Bytecodes::_drem:
1947    if (Matcher::has_match_rule(Op_ModD)) {
1948      // Generate a ModD node.
1949      b = pop_pair();
1950      a = pop_pair();
1951      // a % b
1952
1953      c = _gvn.transform( new ModDNode(0,a,b) );
1954      d = dprecision_rounding(c);
1955      push_pair( d );
1956    }
1957    else {
1958      // Generate a call.
1959      modd();
1960    }
1961    break;
1962
1963  case Bytecodes::_dcmpl:
1964    b = pop_pair();
1965    a = pop_pair();
1966    c = _gvn.transform( new CmpD3Node( a, b));
1967    push(c);
1968    break;
1969
1970  case Bytecodes::_dcmpg:
1971    b = pop_pair();
1972    a = pop_pair();
1973    // Same as dcmpl but need to flip the unordered case.
1974    // Commute the inputs, which negates the result sign except for unordered.
1975    // Flip the unordered as well by using CmpD3 which implements
1976    // unordered-lesser instead of unordered-greater semantics.
1977    // Finally, negate the result bits.  Result is same as using a
1978    // CmpD3Greater except we did it with CmpD3 alone.
1979    c = _gvn.transform( new CmpD3Node( b, a));
1980    c = _gvn.transform( new SubINode(_gvn.intcon(0),c) );
1981    push(c);
1982    break;
1983
1984
1985    // Note for longs -> lo word is on TOS, hi word is on TOS - 1
1986  case Bytecodes::_land:
1987    b = pop_pair();
1988    a = pop_pair();
1989    c = _gvn.transform( new AndLNode(a,b) );
1990    push_pair(c);
1991    break;
1992  case Bytecodes::_lor:
1993    b = pop_pair();
1994    a = pop_pair();
1995    c = _gvn.transform( new OrLNode(a,b) );
1996    push_pair(c);
1997    break;
1998  case Bytecodes::_lxor:
1999    b = pop_pair();
2000    a = pop_pair();
2001    c = _gvn.transform( new XorLNode(a,b) );
2002    push_pair(c);
2003    break;
2004
2005  case Bytecodes::_lshl:
2006    b = pop();                  // the shift count
2007    a = pop_pair();             // value to be shifted
2008    c = _gvn.transform( new LShiftLNode(a,b) );
2009    push_pair(c);
2010    break;
2011  case Bytecodes::_lshr:
2012    b = pop();                  // the shift count
2013    a = pop_pair();             // value to be shifted
2014    c = _gvn.transform( new RShiftLNode(a,b) );
2015    push_pair(c);
2016    break;
2017  case Bytecodes::_lushr:
2018    b = pop();                  // the shift count
2019    a = pop_pair();             // value to be shifted
2020    c = _gvn.transform( new URShiftLNode(a,b) );
2021    push_pair(c);
2022    break;
2023  case Bytecodes::_lmul:
2024    b = pop_pair();
2025    a = pop_pair();
2026    c = _gvn.transform( new MulLNode(a,b) );
2027    push_pair(c);
2028    break;
2029
2030  case Bytecodes::_lrem:
2031    // Must keep both values on the expression-stack during null-check
2032    assert(peek(0) == top(), "long word order");
2033    zero_check_long(peek(1));
2034    // Compile-time detect of null-exception?
2035    if (stopped())  return;
2036    b = pop_pair();
2037    a = pop_pair();
2038    c = _gvn.transform( new ModLNode(control(),a,b) );
2039    push_pair(c);
2040    break;
2041
2042  case Bytecodes::_ldiv:
2043    // Must keep both values on the expression-stack during null-check
2044    assert(peek(0) == top(), "long word order");
2045    zero_check_long(peek(1));
2046    // Compile-time detect of null-exception?
2047    if (stopped())  return;
2048    b = pop_pair();
2049    a = pop_pair();
2050    c = _gvn.transform( new DivLNode(control(),a,b) );
2051    push_pair(c);
2052    break;
2053
2054  case Bytecodes::_ladd:
2055    b = pop_pair();
2056    a = pop_pair();
2057    c = _gvn.transform( new AddLNode(a,b) );
2058    push_pair(c);
2059    break;
2060  case Bytecodes::_lsub:
2061    b = pop_pair();
2062    a = pop_pair();
2063    c = _gvn.transform( new SubLNode(a,b) );
2064    push_pair(c);
2065    break;
2066  case Bytecodes::_lcmp:
2067    // Safepoints are now inserted _before_ branches.  The long-compare
2068    // bytecode painfully produces a 3-way value (-1,0,+1) which requires a
2069    // slew of control flow.  These are usually followed by a CmpI vs zero and
2070    // a branch; this pattern then optimizes to the obvious long-compare and
2071    // branch.  However, if the branch is backwards there's a Safepoint
2072    // inserted.  The inserted Safepoint captures the JVM state at the
2073    // pre-branch point, i.e. it captures the 3-way value.  Thus if a
2074    // long-compare is used to control a loop the debug info will force
2075    // computation of the 3-way value, even though the generated code uses a
2076    // long-compare and branch.  We try to rectify the situation by inserting
2077    // a SafePoint here and have it dominate and kill the safepoint added at a
2078    // following backwards branch.  At this point the JVM state merely holds 2
2079    // longs but not the 3-way value.
2080    if( UseLoopSafepoints ) {
2081      switch( iter().next_bc() ) {
2082      case Bytecodes::_ifgt:
2083      case Bytecodes::_iflt:
2084      case Bytecodes::_ifge:
2085      case Bytecodes::_ifle:
2086      case Bytecodes::_ifne:
2087      case Bytecodes::_ifeq:
2088        // If this is a backwards branch in the bytecodes, add Safepoint
2089        maybe_add_safepoint(iter().next_get_dest());
2090      }
2091    }
2092    b = pop_pair();
2093    a = pop_pair();
2094    c = _gvn.transform( new CmpL3Node( a, b ));
2095    push(c);
2096    break;
2097
2098  case Bytecodes::_lneg:
2099    a = pop_pair();
2100    b = _gvn.transform( new SubLNode(longcon(0),a));
2101    push_pair(b);
2102    break;
2103  case Bytecodes::_l2i:
2104    a = pop_pair();
2105    push( _gvn.transform( new ConvL2INode(a)));
2106    break;
2107  case Bytecodes::_i2l:
2108    a = pop();
2109    b = _gvn.transform( new ConvI2LNode(a));
2110    push_pair(b);
2111    break;
2112  case Bytecodes::_i2b:
2113    // Sign extend
2114    a = pop();
2115    a = _gvn.transform( new LShiftINode(a,_gvn.intcon(24)) );
2116    a = _gvn.transform( new RShiftINode(a,_gvn.intcon(24)) );
2117    push( a );
2118    break;
2119  case Bytecodes::_i2s:
2120    a = pop();
2121    a = _gvn.transform( new LShiftINode(a,_gvn.intcon(16)) );
2122    a = _gvn.transform( new RShiftINode(a,_gvn.intcon(16)) );
2123    push( a );
2124    break;
2125  case Bytecodes::_i2c:
2126    a = pop();
2127    push( _gvn.transform( new AndINode(a,_gvn.intcon(0xFFFF)) ) );
2128    break;
2129
2130  case Bytecodes::_i2f:
2131    a = pop();
2132    b = _gvn.transform( new ConvI2FNode(a) ) ;
2133    c = precision_rounding(b);
2134    push (b);
2135    break;
2136
2137  case Bytecodes::_i2d:
2138    a = pop();
2139    b = _gvn.transform( new ConvI2DNode(a));
2140    push_pair(b);
2141    break;
2142
2143  case Bytecodes::_iinc:        // Increment local
2144    i = iter().get_index();     // Get local index
2145    set_local( i, _gvn.transform( new AddINode( _gvn.intcon(iter().get_iinc_con()), local(i) ) ) );
2146    break;
2147
2148  // Exit points of synchronized methods must have an unlock node
2149  case Bytecodes::_return:
2150    return_current(NULL);
2151    break;
2152
2153  case Bytecodes::_ireturn:
2154  case Bytecodes::_areturn:
2155  case Bytecodes::_freturn:
2156    return_current(pop());
2157    break;
2158  case Bytecodes::_lreturn:
2159    return_current(pop_pair());
2160    break;
2161  case Bytecodes::_dreturn:
2162    return_current(pop_pair());
2163    break;
2164
2165  case Bytecodes::_athrow:
2166    // null exception oop throws NULL pointer exception
2167    null_check(peek());
2168    if (stopped())  return;
2169    // Hook the thrown exception directly to subsequent handlers.
2170    if (BailoutToInterpreterForThrows) {
2171      // Keep method interpreted from now on.
2172      uncommon_trap(Deoptimization::Reason_unhandled,
2173                    Deoptimization::Action_make_not_compilable);
2174      return;
2175    }
2176    if (env()->jvmti_can_post_on_exceptions()) {
2177      // check if we must post exception events, take uncommon trap if so (with must_throw = false)
2178      uncommon_trap_if_should_post_on_exceptions(Deoptimization::Reason_unhandled, false);
2179    }
2180    // Here if either can_post_on_exceptions or should_post_on_exceptions is false
2181    add_exception_state(make_exception_state(peek()));
2182    break;
2183
2184  case Bytecodes::_goto:   // fall through
2185  case Bytecodes::_goto_w: {
2186    int target_bci = (bc() == Bytecodes::_goto) ? iter().get_dest() : iter().get_far_dest();
2187
2188    // If this is a backwards branch in the bytecodes, add Safepoint
2189    maybe_add_safepoint(target_bci);
2190
2191    // Update method data
2192    profile_taken_branch(target_bci);
2193
2194    // Merge the current control into the target basic block
2195    merge(target_bci);
2196
2197    // See if we can get some profile data and hand it off to the next block
2198    Block *target_block = block()->successor_for_bci(target_bci);
2199    if (target_block->pred_count() != 1)  break;
2200    ciMethodData* methodData = method()->method_data();
2201    if (!methodData->is_mature())  break;
2202    ciProfileData* data = methodData->bci_to_data(bci());
2203    assert( data->is_JumpData(), "" );
2204    int taken = ((ciJumpData*)data)->taken();
2205    taken = method()->scale_count(taken);
2206    target_block->set_count(taken);
2207    break;
2208  }
2209
2210  case Bytecodes::_ifnull:    btest = BoolTest::eq; goto handle_if_null;
2211  case Bytecodes::_ifnonnull: btest = BoolTest::ne; goto handle_if_null;
2212  handle_if_null:
2213    // If this is a backwards branch in the bytecodes, add Safepoint
2214    maybe_add_safepoint(iter().get_dest());
2215    a = null();
2216    b = pop();
2217    if (!_gvn.type(b)->speculative_maybe_null() &&
2218        !too_many_traps(Deoptimization::Reason_speculate_null_check)) {
2219      inc_sp(1);
2220      Node* null_ctl = top();
2221      b = null_check_oop(b, &null_ctl, true, true, true);
2222      assert(null_ctl->is_top(), "no null control here");
2223      dec_sp(1);
2224    }
2225    c = _gvn.transform( new CmpPNode(b, a) );
2226    do_ifnull(btest, c);
2227    break;
2228
2229  case Bytecodes::_if_acmpeq: btest = BoolTest::eq; goto handle_if_acmp;
2230  case Bytecodes::_if_acmpne: btest = BoolTest::ne; goto handle_if_acmp;
2231  handle_if_acmp:
2232    // If this is a backwards branch in the bytecodes, add Safepoint
2233    maybe_add_safepoint(iter().get_dest());
2234    a = pop();
2235    b = pop();
2236    c = _gvn.transform( new CmpPNode(b, a) );
2237    c = optimize_cmp_with_klass(c);
2238    do_if(btest, c);
2239    break;
2240
2241  case Bytecodes::_ifeq: btest = BoolTest::eq; goto handle_ifxx;
2242  case Bytecodes::_ifne: btest = BoolTest::ne; goto handle_ifxx;
2243  case Bytecodes::_iflt: btest = BoolTest::lt; goto handle_ifxx;
2244  case Bytecodes::_ifle: btest = BoolTest::le; goto handle_ifxx;
2245  case Bytecodes::_ifgt: btest = BoolTest::gt; goto handle_ifxx;
2246  case Bytecodes::_ifge: btest = BoolTest::ge; goto handle_ifxx;
2247  handle_ifxx:
2248    // If this is a backwards branch in the bytecodes, add Safepoint
2249    maybe_add_safepoint(iter().get_dest());
2250    a = _gvn.intcon(0);
2251    b = pop();
2252    c = _gvn.transform( new CmpINode(b, a) );
2253    do_if(btest, c);
2254    break;
2255
2256  case Bytecodes::_if_icmpeq: btest = BoolTest::eq; goto handle_if_icmp;
2257  case Bytecodes::_if_icmpne: btest = BoolTest::ne; goto handle_if_icmp;
2258  case Bytecodes::_if_icmplt: btest = BoolTest::lt; goto handle_if_icmp;
2259  case Bytecodes::_if_icmple: btest = BoolTest::le; goto handle_if_icmp;
2260  case Bytecodes::_if_icmpgt: btest = BoolTest::gt; goto handle_if_icmp;
2261  case Bytecodes::_if_icmpge: btest = BoolTest::ge; goto handle_if_icmp;
2262  handle_if_icmp:
2263    // If this is a backwards branch in the bytecodes, add Safepoint
2264    maybe_add_safepoint(iter().get_dest());
2265    a = pop();
2266    b = pop();
2267    c = _gvn.transform( new CmpINode( b, a ) );
2268    do_if(btest, c);
2269    break;
2270
2271  case Bytecodes::_tableswitch:
2272    do_tableswitch();
2273    break;
2274
2275  case Bytecodes::_lookupswitch:
2276    do_lookupswitch();
2277    break;
2278
2279  case Bytecodes::_invokestatic:
2280  case Bytecodes::_invokedynamic:
2281  case Bytecodes::_invokespecial:
2282  case Bytecodes::_invokevirtual:
2283  case Bytecodes::_invokeinterface:
2284    do_call();
2285    break;
2286  case Bytecodes::_checkcast:
2287    do_checkcast();
2288    break;
2289  case Bytecodes::_instanceof:
2290    do_instanceof();
2291    break;
2292  case Bytecodes::_anewarray:
2293    do_anewarray();
2294    break;
2295  case Bytecodes::_newarray:
2296    do_newarray((BasicType)iter().get_index());
2297    break;
2298  case Bytecodes::_multianewarray:
2299    do_multianewarray();
2300    break;
2301  case Bytecodes::_new:
2302    do_new();
2303    break;
2304
2305  case Bytecodes::_jsr:
2306  case Bytecodes::_jsr_w:
2307    do_jsr();
2308    break;
2309
2310  case Bytecodes::_ret:
2311    do_ret();
2312    break;
2313
2314
2315  case Bytecodes::_monitorenter:
2316    do_monitor_enter();
2317    break;
2318
2319  case Bytecodes::_monitorexit:
2320    do_monitor_exit();
2321    break;
2322
2323  case Bytecodes::_breakpoint:
2324    // Breakpoint set concurrently to compile
2325    // %%% use an uncommon trap?
2326    C->record_failure("breakpoint in method");
2327    return;
2328
2329  default:
2330#ifndef PRODUCT
2331    map()->dump(99);
2332#endif
2333    tty->print("\nUnhandled bytecode %s\n", Bytecodes::name(bc()) );
2334    ShouldNotReachHere();
2335  }
2336
2337#ifndef PRODUCT
2338  IdealGraphPrinter *printer = IdealGraphPrinter::printer();
2339  if(printer) {
2340    char buffer[256];
2341    sprintf(buffer, "Bytecode %d: %s", bci(), Bytecodes::name(bc()));
2342    bool old = printer->traverse_outs();
2343    printer->set_traverse_outs(true);
2344    printer->print_method(C, buffer, 4);
2345    printer->set_traverse_outs(old);
2346  }
2347#endif
2348}
2349