parse2.cpp revision 113:ba764ed4b6f2
1/*
2 * Copyright 1998-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25#include "incls/_precompiled.incl"
26#include "incls/_parse2.cpp.incl"
27
28extern int explicit_null_checks_inserted,
29           explicit_null_checks_elided;
30
31//---------------------------------array_load----------------------------------
32void Parse::array_load(BasicType elem_type) {
33  const Type* elem = Type::TOP;
34  Node* adr = array_addressing(elem_type, 0, &elem);
35  if (stopped())  return;     // guarenteed null or range check
36  _sp -= 2;                   // Pop array and index
37  const TypeAryPtr* adr_type = TypeAryPtr::get_array_body_type(elem_type);
38  Node* ld = make_load(control(), adr, elem, elem_type, adr_type);
39  push(ld);
40}
41
42
43//--------------------------------array_store----------------------------------
44void Parse::array_store(BasicType elem_type) {
45  Node* adr = array_addressing(elem_type, 1);
46  if (stopped())  return;     // guarenteed null or range check
47  Node* val = pop();
48  _sp -= 2;                   // Pop array and index
49  const TypeAryPtr* adr_type = TypeAryPtr::get_array_body_type(elem_type);
50  store_to_memory(control(), adr, val, elem_type, adr_type);
51}
52
53
54//------------------------------array_addressing-------------------------------
55// Pull array and index from the stack.  Compute pointer-to-element.
56Node* Parse::array_addressing(BasicType type, int vals, const Type* *result2) {
57  Node *idx   = peek(0+vals);   // Get from stack without popping
58  Node *ary   = peek(1+vals);   // in case of exception
59
60  // Null check the array base, with correct stack contents
61  ary = do_null_check(ary, T_ARRAY);
62  // Compile-time detect of null-exception?
63  if (stopped())  return top();
64
65  const TypeAryPtr* arytype  = _gvn.type(ary)->is_aryptr();
66  const TypeInt*    sizetype = arytype->size();
67  const Type*       elemtype = arytype->elem();
68
69  if (UseUniqueSubclasses && result2 != NULL) {
70    const Type* el = elemtype;
71    if (elemtype->isa_narrowoop()) {
72      el = elemtype->is_narrowoop()->make_oopptr();
73    }
74    const TypeInstPtr* toop = el->isa_instptr();
75    if (toop) {
76      if (toop->klass()->as_instance_klass()->unique_concrete_subklass()) {
77        // If we load from "AbstractClass[]" we must see "ConcreteSubClass".
78        const Type* subklass = Type::get_const_type(toop->klass());
79        elemtype = subklass->join(el);
80      }
81    }
82  }
83
84  // Check for big class initializers with all constant offsets
85  // feeding into a known-size array.
86  const TypeInt* idxtype = _gvn.type(idx)->is_int();
87  // See if the highest idx value is less than the lowest array bound,
88  // and if the idx value cannot be negative:
89  bool need_range_check = true;
90  if (idxtype->_hi < sizetype->_lo && idxtype->_lo >= 0) {
91    need_range_check = false;
92    if (C->log() != NULL)   C->log()->elem("observe that='!need_range_check'");
93  }
94
95  if (!arytype->klass()->is_loaded()) {
96    // Only fails for some -Xcomp runs
97    // The class is unloaded.  We have to run this bytecode in the interpreter.
98    uncommon_trap(Deoptimization::Reason_unloaded,
99                  Deoptimization::Action_reinterpret,
100                  arytype->klass(), "!loaded array");
101    return top();
102  }
103
104  // Do the range check
105  if (GenerateRangeChecks && need_range_check) {
106    // Range is constant in array-oop, so we can use the original state of mem
107    Node* len = load_array_length(ary);
108    // Test length vs index (standard trick using unsigned compare)
109    Node* chk = _gvn.transform( new (C, 3) CmpUNode(idx, len) );
110    BoolTest::mask btest = BoolTest::lt;
111    Node* tst = _gvn.transform( new (C, 2) BoolNode(chk, btest) );
112    // Branch to failure if out of bounds
113    { BuildCutout unless(this, tst, PROB_MAX);
114      if (C->allow_range_check_smearing()) {
115        // Do not use builtin_throw, since range checks are sometimes
116        // made more stringent by an optimistic transformation.
117        // This creates "tentative" range checks at this point,
118        // which are not guaranteed to throw exceptions.
119        // See IfNode::Ideal, is_range_check, adjust_check.
120        uncommon_trap(Deoptimization::Reason_range_check,
121                      Deoptimization::Action_make_not_entrant,
122                      NULL, "range_check");
123      } else {
124        // If we have already recompiled with the range-check-widening
125        // heroic optimization turned off, then we must really be throwing
126        // range check exceptions.
127        builtin_throw(Deoptimization::Reason_range_check, idx);
128      }
129    }
130  }
131  // Check for always knowing you are throwing a range-check exception
132  if (stopped())  return top();
133
134  Node* ptr = array_element_address( ary, idx, type, sizetype);
135
136  if (result2 != NULL)  *result2 = elemtype;
137  return ptr;
138}
139
140
141// returns IfNode
142IfNode* Parse::jump_if_fork_int(Node* a, Node* b, BoolTest::mask mask) {
143  Node   *cmp = _gvn.transform( new (C, 3) CmpINode( a, b)); // two cases: shiftcount > 32 and shiftcount <= 32
144  Node   *tst = _gvn.transform( new (C, 2) BoolNode( cmp, mask));
145  IfNode *iff = create_and_map_if( control(), tst, ((mask == BoolTest::eq) ? PROB_STATIC_INFREQUENT : PROB_FAIR), COUNT_UNKNOWN );
146  return iff;
147}
148
149// return Region node
150Node* Parse::jump_if_join(Node* iffalse, Node* iftrue) {
151  Node *region  = new (C, 3) RegionNode(3); // 2 results
152  record_for_igvn(region);
153  region->init_req(1, iffalse);
154  region->init_req(2, iftrue );
155  _gvn.set_type(region, Type::CONTROL);
156  region = _gvn.transform(region);
157  set_control (region);
158  return region;
159}
160
161
162//------------------------------helper for tableswitch-------------------------
163void Parse::jump_if_true_fork(IfNode *iff, int dest_bci_if_true, int prof_table_index) {
164  // True branch, use existing map info
165  { PreserveJVMState pjvms(this);
166    Node *iftrue  = _gvn.transform( new (C, 1) IfTrueNode (iff) );
167    set_control( iftrue );
168    profile_switch_case(prof_table_index);
169    merge_new_path(dest_bci_if_true);
170  }
171
172  // False branch
173  Node *iffalse = _gvn.transform( new (C, 1) IfFalseNode(iff) );
174  set_control( iffalse );
175}
176
177void Parse::jump_if_false_fork(IfNode *iff, int dest_bci_if_true, int prof_table_index) {
178  // True branch, use existing map info
179  { PreserveJVMState pjvms(this);
180    Node *iffalse  = _gvn.transform( new (C, 1) IfFalseNode (iff) );
181    set_control( iffalse );
182    profile_switch_case(prof_table_index);
183    merge_new_path(dest_bci_if_true);
184  }
185
186  // False branch
187  Node *iftrue = _gvn.transform( new (C, 1) IfTrueNode(iff) );
188  set_control( iftrue );
189}
190
191void Parse::jump_if_always_fork(int dest_bci, int prof_table_index) {
192  // False branch, use existing map and control()
193  profile_switch_case(prof_table_index);
194  merge_new_path(dest_bci);
195}
196
197
198extern "C" {
199  static int jint_cmp(const void *i, const void *j) {
200    int a = *(jint *)i;
201    int b = *(jint *)j;
202    return a > b ? 1 : a < b ? -1 : 0;
203  }
204}
205
206
207// Default value for methodData switch indexing. Must be a negative value to avoid
208// conflict with any legal switch index.
209#define NullTableIndex -1
210
211class SwitchRange : public StackObj {
212  // a range of integers coupled with a bci destination
213  jint _lo;                     // inclusive lower limit
214  jint _hi;                     // inclusive upper limit
215  int _dest;
216  int _table_index;             // index into method data table
217
218public:
219  jint lo() const              { return _lo;   }
220  jint hi() const              { return _hi;   }
221  int  dest() const            { return _dest; }
222  int  table_index() const     { return _table_index; }
223  bool is_singleton() const    { return _lo == _hi; }
224
225  void setRange(jint lo, jint hi, int dest, int table_index) {
226    assert(lo <= hi, "must be a non-empty range");
227    _lo = lo, _hi = hi; _dest = dest; _table_index = table_index;
228  }
229  bool adjoinRange(jint lo, jint hi, int dest, int table_index) {
230    assert(lo <= hi, "must be a non-empty range");
231    if (lo == _hi+1 && dest == _dest && table_index == _table_index) {
232      _hi = hi;
233      return true;
234    }
235    return false;
236  }
237
238  void set (jint value, int dest, int table_index) {
239    setRange(value, value, dest, table_index);
240  }
241  bool adjoin(jint value, int dest, int table_index) {
242    return adjoinRange(value, value, dest, table_index);
243  }
244
245  void print(ciEnv* env) {
246    if (is_singleton())
247      tty->print(" {%d}=>%d", lo(), dest());
248    else if (lo() == min_jint)
249      tty->print(" {..%d}=>%d", hi(), dest());
250    else if (hi() == max_jint)
251      tty->print(" {%d..}=>%d", lo(), dest());
252    else
253      tty->print(" {%d..%d}=>%d", lo(), hi(), dest());
254  }
255};
256
257
258//-------------------------------do_tableswitch--------------------------------
259void Parse::do_tableswitch() {
260  Node* lookup = pop();
261
262  // Get information about tableswitch
263  int default_dest = iter().get_dest_table(0);
264  int lo_index     = iter().get_int_table(1);
265  int hi_index     = iter().get_int_table(2);
266  int len          = hi_index - lo_index + 1;
267
268  if (len < 1) {
269    // If this is a backward branch, add safepoint
270    maybe_add_safepoint(default_dest);
271    merge(default_dest);
272    return;
273  }
274
275  // generate decision tree, using trichotomy when possible
276  int rnum = len+2;
277  bool makes_backward_branch = false;
278  SwitchRange* ranges = NEW_RESOURCE_ARRAY(SwitchRange, rnum);
279  int rp = -1;
280  if (lo_index != min_jint) {
281    ranges[++rp].setRange(min_jint, lo_index-1, default_dest, NullTableIndex);
282  }
283  for (int j = 0; j < len; j++) {
284    jint match_int = lo_index+j;
285    int  dest      = iter().get_dest_table(j+3);
286    makes_backward_branch |= (dest <= bci());
287    int  table_index = method_data_update() ? j : NullTableIndex;
288    if (rp < 0 || !ranges[rp].adjoin(match_int, dest, table_index)) {
289      ranges[++rp].set(match_int, dest, table_index);
290    }
291  }
292  jint highest = lo_index+(len-1);
293  assert(ranges[rp].hi() == highest, "");
294  if (highest != max_jint
295      && !ranges[rp].adjoinRange(highest+1, max_jint, default_dest, NullTableIndex)) {
296    ranges[++rp].setRange(highest+1, max_jint, default_dest, NullTableIndex);
297  }
298  assert(rp < len+2, "not too many ranges");
299
300  // Safepoint in case if backward branch observed
301  if( makes_backward_branch && UseLoopSafepoints )
302    add_safepoint();
303
304  jump_switch_ranges(lookup, &ranges[0], &ranges[rp]);
305}
306
307
308//------------------------------do_lookupswitch--------------------------------
309void Parse::do_lookupswitch() {
310  Node *lookup = pop();         // lookup value
311  // Get information about lookupswitch
312  int default_dest = iter().get_dest_table(0);
313  int len          = iter().get_int_table(1);
314
315  if (len < 1) {    // If this is a backward branch, add safepoint
316    maybe_add_safepoint(default_dest);
317    merge(default_dest);
318    return;
319  }
320
321  // generate decision tree, using trichotomy when possible
322  jint* table = NEW_RESOURCE_ARRAY(jint, len*2);
323  {
324    for( int j = 0; j < len; j++ ) {
325      table[j+j+0] = iter().get_int_table(2+j+j);
326      table[j+j+1] = iter().get_dest_table(2+j+j+1);
327    }
328    qsort( table, len, 2*sizeof(table[0]), jint_cmp );
329  }
330
331  int rnum = len*2+1;
332  bool makes_backward_branch = false;
333  SwitchRange* ranges = NEW_RESOURCE_ARRAY(SwitchRange, rnum);
334  int rp = -1;
335  for( int j = 0; j < len; j++ ) {
336    jint match_int   = table[j+j+0];
337    int  dest        = table[j+j+1];
338    int  next_lo     = rp < 0 ? min_jint : ranges[rp].hi()+1;
339    int  table_index = method_data_update() ? j : NullTableIndex;
340    makes_backward_branch |= (dest <= bci());
341    if( match_int != next_lo ) {
342      ranges[++rp].setRange(next_lo, match_int-1, default_dest, NullTableIndex);
343    }
344    if( rp < 0 || !ranges[rp].adjoin(match_int, dest, table_index) ) {
345      ranges[++rp].set(match_int, dest, table_index);
346    }
347  }
348  jint highest = table[2*(len-1)];
349  assert(ranges[rp].hi() == highest, "");
350  if( highest != max_jint
351      && !ranges[rp].adjoinRange(highest+1, max_jint, default_dest, NullTableIndex) ) {
352    ranges[++rp].setRange(highest+1, max_jint, default_dest, NullTableIndex);
353  }
354  assert(rp < rnum, "not too many ranges");
355
356  // Safepoint in case backward branch observed
357  if( makes_backward_branch && UseLoopSafepoints )
358    add_safepoint();
359
360  jump_switch_ranges(lookup, &ranges[0], &ranges[rp]);
361}
362
363//----------------------------create_jump_tables-------------------------------
364bool Parse::create_jump_tables(Node* key_val, SwitchRange* lo, SwitchRange* hi) {
365  // Are jumptables enabled
366  if (!UseJumpTables)  return false;
367
368  // Are jumptables supported
369  if (!Matcher::has_match_rule(Op_Jump))  return false;
370
371  // Don't make jump table if profiling
372  if (method_data_update())  return false;
373
374  // Decide if a guard is needed to lop off big ranges at either (or
375  // both) end(s) of the input set. We'll call this the default target
376  // even though we can't be sure that it is the true "default".
377
378  bool needs_guard = false;
379  int default_dest;
380  int64 total_outlier_size = 0;
381  int64 hi_size = ((int64)hi->hi()) - ((int64)hi->lo()) + 1;
382  int64 lo_size = ((int64)lo->hi()) - ((int64)lo->lo()) + 1;
383
384  if (lo->dest() == hi->dest()) {
385    total_outlier_size = hi_size + lo_size;
386    default_dest = lo->dest();
387  } else if (lo_size > hi_size) {
388    total_outlier_size = lo_size;
389    default_dest = lo->dest();
390  } else {
391    total_outlier_size = hi_size;
392    default_dest = hi->dest();
393  }
394
395  // If a guard test will eliminate very sparse end ranges, then
396  // it is worth the cost of an extra jump.
397  if (total_outlier_size > (MaxJumpTableSparseness * 4)) {
398    needs_guard = true;
399    if (default_dest == lo->dest()) lo++;
400    if (default_dest == hi->dest()) hi--;
401  }
402
403  // Find the total number of cases and ranges
404  int64 num_cases = ((int64)hi->hi()) - ((int64)lo->lo()) + 1;
405  int num_range = hi - lo + 1;
406
407  // Don't create table if: too large, too small, or too sparse.
408  if (num_cases < MinJumpTableSize || num_cases > MaxJumpTableSize)
409    return false;
410  if (num_cases > (MaxJumpTableSparseness * num_range))
411    return false;
412
413  // Normalize table lookups to zero
414  int lowval = lo->lo();
415  key_val = _gvn.transform( new (C, 3) SubINode(key_val, _gvn.intcon(lowval)) );
416
417  // Generate a guard to protect against input keyvals that aren't
418  // in the switch domain.
419  if (needs_guard) {
420    Node*   size = _gvn.intcon(num_cases);
421    Node*   cmp = _gvn.transform( new (C, 3) CmpUNode(key_val, size) );
422    Node*   tst = _gvn.transform( new (C, 2) BoolNode(cmp, BoolTest::ge) );
423    IfNode* iff = create_and_map_if( control(), tst, PROB_FAIR, COUNT_UNKNOWN);
424    jump_if_true_fork(iff, default_dest, NullTableIndex);
425  }
426
427  // Create an ideal node JumpTable that has projections
428  // of all possible ranges for a switch statement
429  // The key_val input must be converted to a pointer offset and scaled.
430  // Compare Parse::array_addressing above.
431#ifdef _LP64
432  // Clean the 32-bit int into a real 64-bit offset.
433  // Otherwise, the jint value 0 might turn into an offset of 0x0800000000.
434  const TypeLong* lkeytype = TypeLong::make(CONST64(0), num_cases-1, Type::WidenMin);
435  key_val       = _gvn.transform( new (C, 2) ConvI2LNode(key_val, lkeytype) );
436#endif
437  // Shift the value by wordsize so we have an index into the table, rather
438  // than a switch value
439  Node *shiftWord = _gvn.MakeConX(wordSize);
440  key_val = _gvn.transform( new (C, 3) MulXNode( key_val, shiftWord));
441
442  // Create the JumpNode
443  Node* jtn = _gvn.transform( new (C, 2) JumpNode(control(), key_val, num_cases) );
444
445  // These are the switch destinations hanging off the jumpnode
446  int i = 0;
447  for (SwitchRange* r = lo; r <= hi; r++) {
448    for (int j = r->lo(); j <= r->hi(); j++, i++) {
449      Node* input = _gvn.transform(new (C, 1) JumpProjNode(jtn, i, r->dest(), j - lowval));
450      {
451        PreserveJVMState pjvms(this);
452        set_control(input);
453        jump_if_always_fork(r->dest(), r->table_index());
454      }
455    }
456  }
457  assert(i == num_cases, "miscount of cases");
458  stop_and_kill_map();  // no more uses for this JVMS
459  return true;
460}
461
462//----------------------------jump_switch_ranges-------------------------------
463void Parse::jump_switch_ranges(Node* key_val, SwitchRange *lo, SwitchRange *hi, int switch_depth) {
464  Block* switch_block = block();
465
466  if (switch_depth == 0) {
467    // Do special processing for the top-level call.
468    assert(lo->lo() == min_jint, "initial range must exhaust Type::INT");
469    assert(hi->hi() == max_jint, "initial range must exhaust Type::INT");
470
471    // Decrement pred-numbers for the unique set of nodes.
472#ifdef ASSERT
473    // Ensure that the block's successors are a (duplicate-free) set.
474    int successors_counted = 0;  // block occurrences in [hi..lo]
475    int unique_successors = switch_block->num_successors();
476    for (int i = 0; i < unique_successors; i++) {
477      Block* target = switch_block->successor_at(i);
478
479      // Check that the set of successors is the same in both places.
480      int successors_found = 0;
481      for (SwitchRange* p = lo; p <= hi; p++) {
482        if (p->dest() == target->start())  successors_found++;
483      }
484      assert(successors_found > 0, "successor must be known");
485      successors_counted += successors_found;
486    }
487    assert(successors_counted == (hi-lo)+1, "no unexpected successors");
488#endif
489
490    // Maybe prune the inputs, based on the type of key_val.
491    jint min_val = min_jint;
492    jint max_val = max_jint;
493    const TypeInt* ti = key_val->bottom_type()->isa_int();
494    if (ti != NULL) {
495      min_val = ti->_lo;
496      max_val = ti->_hi;
497      assert(min_val <= max_val, "invalid int type");
498    }
499    while (lo->hi() < min_val)  lo++;
500    if (lo->lo() < min_val)  lo->setRange(min_val, lo->hi(), lo->dest(), lo->table_index());
501    while (hi->lo() > max_val)  hi--;
502    if (hi->hi() > max_val)  hi->setRange(hi->lo(), max_val, hi->dest(), hi->table_index());
503  }
504
505#ifndef PRODUCT
506  if (switch_depth == 0) {
507    _max_switch_depth = 0;
508    _est_switch_depth = log2_intptr((hi-lo+1)-1)+1;
509  }
510#endif
511
512  assert(lo <= hi, "must be a non-empty set of ranges");
513  if (lo == hi) {
514    jump_if_always_fork(lo->dest(), lo->table_index());
515  } else {
516    assert(lo->hi() == (lo+1)->lo()-1, "contiguous ranges");
517    assert(hi->lo() == (hi-1)->hi()+1, "contiguous ranges");
518
519    if (create_jump_tables(key_val, lo, hi)) return;
520
521    int nr = hi - lo + 1;
522
523    SwitchRange* mid = lo + nr/2;
524    // if there is an easy choice, pivot at a singleton:
525    if (nr > 3 && !mid->is_singleton() && (mid-1)->is_singleton())  mid--;
526
527    assert(lo < mid && mid <= hi, "good pivot choice");
528    assert(nr != 2 || mid == hi,   "should pick higher of 2");
529    assert(nr != 3 || mid == hi-1, "should pick middle of 3");
530
531    Node *test_val = _gvn.intcon(mid->lo());
532
533    if (mid->is_singleton()) {
534      IfNode *iff_ne = jump_if_fork_int(key_val, test_val, BoolTest::ne);
535      jump_if_false_fork(iff_ne, mid->dest(), mid->table_index());
536
537      // Special Case:  If there are exactly three ranges, and the high
538      // and low range each go to the same place, omit the "gt" test,
539      // since it will not discriminate anything.
540      bool eq_test_only = (hi == lo+2 && hi->dest() == lo->dest());
541      if (eq_test_only) {
542        assert(mid == hi-1, "");
543      }
544
545      // if there is a higher range, test for it and process it:
546      if (mid < hi && !eq_test_only) {
547        // two comparisons of same values--should enable 1 test for 2 branches
548        // Use BoolTest::le instead of BoolTest::gt
549        IfNode *iff_le  = jump_if_fork_int(key_val, test_val, BoolTest::le);
550        Node   *iftrue  = _gvn.transform( new (C, 1) IfTrueNode(iff_le) );
551        Node   *iffalse = _gvn.transform( new (C, 1) IfFalseNode(iff_le) );
552        { PreserveJVMState pjvms(this);
553          set_control(iffalse);
554          jump_switch_ranges(key_val, mid+1, hi, switch_depth+1);
555        }
556        set_control(iftrue);
557      }
558
559    } else {
560      // mid is a range, not a singleton, so treat mid..hi as a unit
561      IfNode *iff_ge = jump_if_fork_int(key_val, test_val, BoolTest::ge);
562
563      // if there is a higher range, test for it and process it:
564      if (mid == hi) {
565        jump_if_true_fork(iff_ge, mid->dest(), mid->table_index());
566      } else {
567        Node *iftrue  = _gvn.transform( new (C, 1) IfTrueNode(iff_ge) );
568        Node *iffalse = _gvn.transform( new (C, 1) IfFalseNode(iff_ge) );
569        { PreserveJVMState pjvms(this);
570          set_control(iftrue);
571          jump_switch_ranges(key_val, mid, hi, switch_depth+1);
572        }
573        set_control(iffalse);
574      }
575    }
576
577    // in any case, process the lower range
578    jump_switch_ranges(key_val, lo, mid-1, switch_depth+1);
579  }
580
581  // Decrease pred_count for each successor after all is done.
582  if (switch_depth == 0) {
583    int unique_successors = switch_block->num_successors();
584    for (int i = 0; i < unique_successors; i++) {
585      Block* target = switch_block->successor_at(i);
586      // Throw away the pre-allocated path for each unique successor.
587      target->next_path_num();
588    }
589  }
590
591#ifndef PRODUCT
592  _max_switch_depth = MAX2(switch_depth, _max_switch_depth);
593  if (TraceOptoParse && Verbose && WizardMode && switch_depth == 0) {
594    SwitchRange* r;
595    int nsing = 0;
596    for( r = lo; r <= hi; r++ ) {
597      if( r->is_singleton() )  nsing++;
598    }
599    tty->print(">>> ");
600    _method->print_short_name();
601    tty->print_cr(" switch decision tree");
602    tty->print_cr("    %d ranges (%d singletons), max_depth=%d, est_depth=%d",
603                  hi-lo+1, nsing, _max_switch_depth, _est_switch_depth);
604    if (_max_switch_depth > _est_switch_depth) {
605      tty->print_cr("******** BAD SWITCH DEPTH ********");
606    }
607    tty->print("   ");
608    for( r = lo; r <= hi; r++ ) {
609      r->print(env());
610    }
611    tty->print_cr("");
612  }
613#endif
614}
615
616void Parse::modf() {
617  Node *f2 = pop();
618  Node *f1 = pop();
619  Node* c = make_runtime_call(RC_LEAF, OptoRuntime::modf_Type(),
620                              CAST_FROM_FN_PTR(address, SharedRuntime::frem),
621                              "frem", NULL, //no memory effects
622                              f1, f2);
623  Node* res = _gvn.transform(new (C, 1) ProjNode(c, TypeFunc::Parms + 0));
624
625  push(res);
626}
627
628void Parse::modd() {
629  Node *d2 = pop_pair();
630  Node *d1 = pop_pair();
631  Node* c = make_runtime_call(RC_LEAF, OptoRuntime::Math_DD_D_Type(),
632                              CAST_FROM_FN_PTR(address, SharedRuntime::drem),
633                              "drem", NULL, //no memory effects
634                              d1, top(), d2, top());
635  Node* res_d   = _gvn.transform(new (C, 1) ProjNode(c, TypeFunc::Parms + 0));
636
637#ifdef ASSERT
638  Node* res_top = _gvn.transform(new (C, 1) ProjNode(c, TypeFunc::Parms + 1));
639  assert(res_top == top(), "second value must be top");
640#endif
641
642  push_pair(res_d);
643}
644
645void Parse::l2f() {
646  Node* f2 = pop();
647  Node* f1 = pop();
648  Node* c = make_runtime_call(RC_LEAF, OptoRuntime::l2f_Type(),
649                              CAST_FROM_FN_PTR(address, SharedRuntime::l2f),
650                              "l2f", NULL, //no memory effects
651                              f1, f2);
652  Node* res = _gvn.transform(new (C, 1) ProjNode(c, TypeFunc::Parms + 0));
653
654  push(res);
655}
656
657void Parse::do_irem() {
658  // Must keep both values on the expression-stack during null-check
659  do_null_check(peek(), T_INT);
660  // Compile-time detect of null-exception?
661  if (stopped())  return;
662
663  Node* b = pop();
664  Node* a = pop();
665
666  const Type *t = _gvn.type(b);
667  if (t != Type::TOP) {
668    const TypeInt *ti = t->is_int();
669    if (ti->is_con()) {
670      int divisor = ti->get_con();
671      // check for positive power of 2
672      if (divisor > 0 &&
673          (divisor & ~(divisor-1)) == divisor) {
674        // yes !
675        Node *mask = _gvn.intcon((divisor - 1));
676        // Sigh, must handle negative dividends
677        Node *zero = _gvn.intcon(0);
678        IfNode *ifff = jump_if_fork_int(a, zero, BoolTest::lt);
679        Node *iff = _gvn.transform( new (C, 1) IfFalseNode(ifff) );
680        Node *ift = _gvn.transform( new (C, 1) IfTrueNode (ifff) );
681        Node *reg = jump_if_join(ift, iff);
682        Node *phi = PhiNode::make(reg, NULL, TypeInt::INT);
683        // Negative path; negate/and/negate
684        Node *neg = _gvn.transform( new (C, 3) SubINode(zero, a) );
685        Node *andn= _gvn.transform( new (C, 3) AndINode(neg, mask) );
686        Node *negn= _gvn.transform( new (C, 3) SubINode(zero, andn) );
687        phi->init_req(1, negn);
688        // Fast positive case
689        Node *andx = _gvn.transform( new (C, 3) AndINode(a, mask) );
690        phi->init_req(2, andx);
691        // Push the merge
692        push( _gvn.transform(phi) );
693        return;
694      }
695    }
696  }
697  // Default case
698  push( _gvn.transform( new (C, 3) ModINode(control(),a,b) ) );
699}
700
701// Handle jsr and jsr_w bytecode
702void Parse::do_jsr() {
703  assert(bc() == Bytecodes::_jsr || bc() == Bytecodes::_jsr_w, "wrong bytecode");
704
705  // Store information about current state, tagged with new _jsr_bci
706  int return_bci = iter().next_bci();
707  int jsr_bci    = (bc() == Bytecodes::_jsr) ? iter().get_dest() : iter().get_far_dest();
708
709  // Update method data
710  profile_taken_branch(jsr_bci);
711
712  // The way we do things now, there is only one successor block
713  // for the jsr, because the target code is cloned by ciTypeFlow.
714  Block* target = successor_for_bci(jsr_bci);
715
716  // What got pushed?
717  const Type* ret_addr = target->peek();
718  assert(ret_addr->singleton(), "must be a constant (cloned jsr body)");
719
720  // Effect on jsr on stack
721  push(_gvn.makecon(ret_addr));
722
723  // Flow to the jsr.
724  merge(jsr_bci);
725}
726
727// Handle ret bytecode
728void Parse::do_ret() {
729  // Find to whom we return.
730#if 0 // %%%% MAKE THIS WORK
731  Node* con = local();
732  const TypePtr* tp = con->bottom_type()->isa_ptr();
733  assert(tp && tp->singleton(), "");
734  int return_bci = (int) tp->get_con();
735  merge(return_bci);
736#else
737  assert(block()->num_successors() == 1, "a ret can only go one place now");
738  Block* target = block()->successor_at(0);
739  assert(!target->is_ready(), "our arrival must be expected");
740  profile_ret(target->flow()->start());
741  int pnum = target->next_path_num();
742  merge_common(target, pnum);
743#endif
744}
745
746//--------------------------dynamic_branch_prediction--------------------------
747// Try to gather dynamic branch prediction behavior.  Return a probability
748// of the branch being taken and set the "cnt" field.  Returns a -1.0
749// if we need to use static prediction for some reason.
750float Parse::dynamic_branch_prediction(float &cnt) {
751  ResourceMark rm;
752
753  cnt  = COUNT_UNKNOWN;
754
755  // Use MethodData information if it is available
756  // FIXME: free the ProfileData structure
757  ciMethodData* methodData = method()->method_data();
758  if (!methodData->is_mature())  return PROB_UNKNOWN;
759  ciProfileData* data = methodData->bci_to_data(bci());
760  if (!data->is_JumpData())  return PROB_UNKNOWN;
761
762  // get taken and not taken values
763  int     taken = data->as_JumpData()->taken();
764  int not_taken = 0;
765  if (data->is_BranchData()) {
766    not_taken = data->as_BranchData()->not_taken();
767  }
768
769  // scale the counts to be commensurate with invocation counts:
770  taken = method()->scale_count(taken);
771  not_taken = method()->scale_count(not_taken);
772
773  // Give up if too few counts to be meaningful
774  if (taken + not_taken < 40) {
775    if (C->log() != NULL) {
776      C->log()->elem("branch target_bci='%d' taken='%d' not_taken='%d'", iter().get_dest(), taken, not_taken);
777    }
778    return PROB_UNKNOWN;
779  }
780
781  // Compute frequency that we arrive here
782  int sum = taken + not_taken;
783  // Adjust, if this block is a cloned private block but the
784  // Jump counts are shared.  Taken the private counts for
785  // just this path instead of the shared counts.
786  if( block()->count() > 0 )
787    sum = block()->count();
788  cnt = (float)sum / (float)FreqCountInvocations;
789
790  // Pin probability to sane limits
791  float prob;
792  if( !taken )
793    prob = (0+PROB_MIN) / 2;
794  else if( !not_taken )
795    prob = (1+PROB_MAX) / 2;
796  else {                         // Compute probability of true path
797    prob = (float)taken / (float)(taken + not_taken);
798    if (prob > PROB_MAX)  prob = PROB_MAX;
799    if (prob < PROB_MIN)   prob = PROB_MIN;
800  }
801
802  assert((cnt > 0.0f) && (prob > 0.0f),
803         "Bad frequency assignment in if");
804
805  if (C->log() != NULL) {
806    const char* prob_str = NULL;
807    if (prob >= PROB_MAX)  prob_str = (prob == PROB_MAX) ? "max" : "always";
808    if (prob <= PROB_MIN)  prob_str = (prob == PROB_MIN) ? "min" : "never";
809    char prob_str_buf[30];
810    if (prob_str == NULL) {
811      sprintf(prob_str_buf, "%g", prob);
812      prob_str = prob_str_buf;
813    }
814    C->log()->elem("branch target_bci='%d' taken='%d' not_taken='%d' cnt='%g' prob='%s'",
815                   iter().get_dest(), taken, not_taken, cnt, prob_str);
816  }
817  return prob;
818}
819
820//-----------------------------branch_prediction-------------------------------
821float Parse::branch_prediction(float& cnt,
822                               BoolTest::mask btest,
823                               int target_bci) {
824  float prob = dynamic_branch_prediction(cnt);
825  // If prob is unknown, switch to static prediction
826  if (prob != PROB_UNKNOWN)  return prob;
827
828  prob = PROB_FAIR;                   // Set default value
829  if (btest == BoolTest::eq)          // Exactly equal test?
830    prob = PROB_STATIC_INFREQUENT;    // Assume its relatively infrequent
831  else if (btest == BoolTest::ne)
832    prob = PROB_STATIC_FREQUENT;      // Assume its relatively frequent
833
834  // If this is a conditional test guarding a backwards branch,
835  // assume its a loop-back edge.  Make it a likely taken branch.
836  if (target_bci < bci()) {
837    if (is_osr_parse()) {    // Could be a hot OSR'd loop; force deopt
838      // Since it's an OSR, we probably have profile data, but since
839      // branch_prediction returned PROB_UNKNOWN, the counts are too small.
840      // Let's make a special check here for completely zero counts.
841      ciMethodData* methodData = method()->method_data();
842      if (!methodData->is_empty()) {
843        ciProfileData* data = methodData->bci_to_data(bci());
844        // Only stop for truly zero counts, which mean an unknown part
845        // of the OSR-ed method, and we want to deopt to gather more stats.
846        // If you have ANY counts, then this loop is simply 'cold' relative
847        // to the OSR loop.
848        if (data->as_BranchData()->taken() +
849            data->as_BranchData()->not_taken() == 0 ) {
850          // This is the only way to return PROB_UNKNOWN:
851          return PROB_UNKNOWN;
852        }
853      }
854    }
855    prob = PROB_STATIC_FREQUENT;     // Likely to take backwards branch
856  }
857
858  assert(prob != PROB_UNKNOWN, "must have some guess at this point");
859  return prob;
860}
861
862// The magic constants are chosen so as to match the output of
863// branch_prediction() when the profile reports a zero taken count.
864// It is important to distinguish zero counts unambiguously, because
865// some branches (e.g., _213_javac.Assembler.eliminate) validly produce
866// very small but nonzero probabilities, which if confused with zero
867// counts would keep the program recompiling indefinitely.
868bool Parse::seems_never_taken(float prob) {
869  return prob < PROB_MIN;
870}
871
872inline void Parse::repush_if_args() {
873#ifndef PRODUCT
874  if (PrintOpto && WizardMode) {
875    tty->print("defending against excessive implicit null exceptions on %s @%d in ",
876               Bytecodes::name(iter().cur_bc()), iter().cur_bci());
877    method()->print_name(); tty->cr();
878  }
879#endif
880  int bc_depth = - Bytecodes::depth(iter().cur_bc());
881  assert(bc_depth == 1 || bc_depth == 2, "only two kinds of branches");
882  DEBUG_ONLY(sync_jvms());   // argument(n) requires a synced jvms
883  assert(argument(0) != NULL, "must exist");
884  assert(bc_depth == 1 || argument(1) != NULL, "two must exist");
885  _sp += bc_depth;
886}
887
888//----------------------------------do_ifnull----------------------------------
889void Parse::do_ifnull(BoolTest::mask btest) {
890  int target_bci = iter().get_dest();
891
892  Block* branch_block = successor_for_bci(target_bci);
893  Block* next_block   = successor_for_bci(iter().next_bci());
894
895  float cnt;
896  float prob = branch_prediction(cnt, btest, target_bci);
897  if (prob == PROB_UNKNOWN) {
898    // (An earlier version of do_ifnull omitted this trap for OSR methods.)
899#ifndef PRODUCT
900    if (PrintOpto && Verbose)
901      tty->print_cr("Never-taken backedge stops compilation at bci %d",bci());
902#endif
903    repush_if_args(); // to gather stats on loop
904    // We need to mark this branch as taken so that if we recompile we will
905    // see that it is possible. In the tiered system the interpreter doesn't
906    // do profiling and by the time we get to the lower tier from the interpreter
907    // the path may be cold again. Make sure it doesn't look untaken
908    profile_taken_branch(target_bci, !ProfileInterpreter);
909    uncommon_trap(Deoptimization::Reason_unreached,
910                  Deoptimization::Action_reinterpret,
911                  NULL, "cold");
912    if (EliminateAutoBox) {
913      // Mark the successor blocks as parsed
914      branch_block->next_path_num();
915      next_block->next_path_num();
916    }
917    return;
918  }
919
920  // If this is a backwards branch in the bytecodes, add Safepoint
921  maybe_add_safepoint(target_bci);
922
923  explicit_null_checks_inserted++;
924  Node* a = null();
925  Node* b = pop();
926  Node* c = _gvn.transform( new (C, 3) CmpPNode(b, a) );
927
928  // Make a cast-away-nullness that is control dependent on the test
929  const Type *t = _gvn.type(b);
930  const Type *t_not_null = t->join(TypePtr::NOTNULL);
931  Node *cast = new (C, 2) CastPPNode(b,t_not_null);
932
933  // Generate real control flow
934  Node   *tst = _gvn.transform( new (C, 2) BoolNode( c, btest ) );
935
936  // Sanity check the probability value
937  assert(prob > 0.0f,"Bad probability in Parser");
938 // Need xform to put node in hash table
939  IfNode *iff = create_and_xform_if( control(), tst, prob, cnt );
940  assert(iff->_prob > 0.0f,"Optimizer made bad probability in parser");
941  // True branch
942  { PreserveJVMState pjvms(this);
943    Node* iftrue  = _gvn.transform( new (C, 1) IfTrueNode (iff) );
944    set_control(iftrue);
945
946    if (stopped()) {            // Path is dead?
947      explicit_null_checks_elided++;
948      if (EliminateAutoBox) {
949        // Mark the successor block as parsed
950        branch_block->next_path_num();
951      }
952    } else {                    // Path is live.
953      // Update method data
954      profile_taken_branch(target_bci);
955      adjust_map_after_if(btest, c, prob, branch_block, next_block);
956      if (!stopped())
957        merge(target_bci);
958    }
959  }
960
961  // False branch
962  Node* iffalse = _gvn.transform( new (C, 1) IfFalseNode(iff) );
963  set_control(iffalse);
964
965  if (stopped()) {              // Path is dead?
966    explicit_null_checks_elided++;
967    if (EliminateAutoBox) {
968      // Mark the successor block as parsed
969      next_block->next_path_num();
970    }
971  } else  {                     // Path is live.
972    // Update method data
973    profile_not_taken_branch();
974    adjust_map_after_if(BoolTest(btest).negate(), c, 1.0-prob,
975                        next_block, branch_block);
976  }
977}
978
979//------------------------------------do_if------------------------------------
980void Parse::do_if(BoolTest::mask btest, Node* c) {
981  int target_bci = iter().get_dest();
982
983  Block* branch_block = successor_for_bci(target_bci);
984  Block* next_block   = successor_for_bci(iter().next_bci());
985
986  float cnt;
987  float prob = branch_prediction(cnt, btest, target_bci);
988  float untaken_prob = 1.0 - prob;
989
990  if (prob == PROB_UNKNOWN) {
991#ifndef PRODUCT
992    if (PrintOpto && Verbose)
993      tty->print_cr("Never-taken backedge stops compilation at bci %d",bci());
994#endif
995    repush_if_args(); // to gather stats on loop
996    // We need to mark this branch as taken so that if we recompile we will
997    // see that it is possible. In the tiered system the interpreter doesn't
998    // do profiling and by the time we get to the lower tier from the interpreter
999    // the path may be cold again. Make sure it doesn't look untaken
1000    profile_taken_branch(target_bci, !ProfileInterpreter);
1001    uncommon_trap(Deoptimization::Reason_unreached,
1002                  Deoptimization::Action_reinterpret,
1003                  NULL, "cold");
1004    if (EliminateAutoBox) {
1005      // Mark the successor blocks as parsed
1006      branch_block->next_path_num();
1007      next_block->next_path_num();
1008    }
1009    return;
1010  }
1011
1012  // Sanity check the probability value
1013  assert(0.0f < prob && prob < 1.0f,"Bad probability in Parser");
1014
1015  bool taken_if_true = true;
1016  // Convert BoolTest to canonical form:
1017  if (!BoolTest(btest).is_canonical()) {
1018    btest         = BoolTest(btest).negate();
1019    taken_if_true = false;
1020    // prob is NOT updated here; it remains the probability of the taken
1021    // path (as opposed to the prob of the path guarded by an 'IfTrueNode').
1022  }
1023  assert(btest != BoolTest::eq, "!= is the only canonical exact test");
1024
1025  Node* tst0 = new (C, 2) BoolNode(c, btest);
1026  Node* tst = _gvn.transform(tst0);
1027  BoolTest::mask taken_btest   = BoolTest::illegal;
1028  BoolTest::mask untaken_btest = BoolTest::illegal;
1029
1030  if (tst->is_Bool()) {
1031    // Refresh c from the transformed bool node, since it may be
1032    // simpler than the original c.  Also re-canonicalize btest.
1033    // This wins when (Bool ne (Conv2B p) 0) => (Bool ne (CmpP p NULL)).
1034    // That can arise from statements like: if (x instanceof C) ...
1035    if (tst != tst0) {
1036      // Canonicalize one more time since transform can change it.
1037      btest = tst->as_Bool()->_test._test;
1038      if (!BoolTest(btest).is_canonical()) {
1039        // Reverse edges one more time...
1040        tst   = _gvn.transform( tst->as_Bool()->negate(&_gvn) );
1041        btest = tst->as_Bool()->_test._test;
1042        assert(BoolTest(btest).is_canonical(), "sanity");
1043        taken_if_true = !taken_if_true;
1044      }
1045      c = tst->in(1);
1046    }
1047    BoolTest::mask neg_btest = BoolTest(btest).negate();
1048    taken_btest   = taken_if_true ?     btest : neg_btest;
1049    untaken_btest = taken_if_true ? neg_btest :     btest;
1050  }
1051
1052  // Generate real control flow
1053  float true_prob = (taken_if_true ? prob : untaken_prob);
1054  IfNode* iff = create_and_map_if(control(), tst, true_prob, cnt);
1055  assert(iff->_prob > 0.0f,"Optimizer made bad probability in parser");
1056  Node* taken_branch   = new (C, 1) IfTrueNode(iff);
1057  Node* untaken_branch = new (C, 1) IfFalseNode(iff);
1058  if (!taken_if_true) {  // Finish conversion to canonical form
1059    Node* tmp      = taken_branch;
1060    taken_branch   = untaken_branch;
1061    untaken_branch = tmp;
1062  }
1063
1064  // Branch is taken:
1065  { PreserveJVMState pjvms(this);
1066    taken_branch = _gvn.transform(taken_branch);
1067    set_control(taken_branch);
1068
1069    if (stopped()) {
1070      if (EliminateAutoBox) {
1071        // Mark the successor block as parsed
1072        branch_block->next_path_num();
1073      }
1074    } else {
1075      // Update method data
1076      profile_taken_branch(target_bci);
1077      adjust_map_after_if(taken_btest, c, prob, branch_block, next_block);
1078      if (!stopped())
1079        merge(target_bci);
1080    }
1081  }
1082
1083  untaken_branch = _gvn.transform(untaken_branch);
1084  set_control(untaken_branch);
1085
1086  // Branch not taken.
1087  if (stopped()) {
1088    if (EliminateAutoBox) {
1089      // Mark the successor block as parsed
1090      next_block->next_path_num();
1091    }
1092  } else {
1093    // Update method data
1094    profile_not_taken_branch();
1095    adjust_map_after_if(untaken_btest, c, untaken_prob,
1096                        next_block, branch_block);
1097  }
1098}
1099
1100//----------------------------adjust_map_after_if------------------------------
1101// Adjust the JVM state to reflect the result of taking this path.
1102// Basically, it means inspecting the CmpNode controlling this
1103// branch, seeing how it constrains a tested value, and then
1104// deciding if it's worth our while to encode this constraint
1105// as graph nodes in the current abstract interpretation map.
1106void Parse::adjust_map_after_if(BoolTest::mask btest, Node* c, float prob,
1107                                Block* path, Block* other_path) {
1108  if (stopped() || !c->is_Cmp() || btest == BoolTest::illegal)
1109    return;                             // nothing to do
1110
1111  bool is_fallthrough = (path == successor_for_bci(iter().next_bci()));
1112
1113  int cop = c->Opcode();
1114  if (seems_never_taken(prob) && cop == Op_CmpP && btest == BoolTest::eq) {
1115    // (An earlier version of do_if omitted '&& btest == BoolTest::eq'.)
1116    //
1117    // If this might possibly turn into an implicit null check,
1118    // and the null has never yet been seen, we need to generate
1119    // an uncommon trap, so as to recompile instead of suffering
1120    // with very slow branches.  (We'll get the slow branches if
1121    // the program ever changes phase and starts seeing nulls here.)
1122    //
1123    // The tests we worry about are of the form (p == null).
1124    // We do not simply inspect for a null constant, since a node may
1125    // optimize to 'null' later on.
1126    repush_if_args();
1127    // We need to mark this branch as taken so that if we recompile we will
1128    // see that it is possible. In the tiered system the interpreter doesn't
1129    // do profiling and by the time we get to the lower tier from the interpreter
1130    // the path may be cold again. Make sure it doesn't look untaken
1131    if (is_fallthrough) {
1132      profile_not_taken_branch(!ProfileInterpreter);
1133    } else {
1134      profile_taken_branch(iter().get_dest(), !ProfileInterpreter);
1135    }
1136    uncommon_trap(Deoptimization::Reason_unreached,
1137                  Deoptimization::Action_reinterpret,
1138                  NULL,
1139                  (is_fallthrough ? "taken always" : "taken never"));
1140    return;
1141  }
1142
1143  Node* val = c->in(1);
1144  Node* con = c->in(2);
1145  const Type* tcon = _gvn.type(con);
1146  const Type* tval = _gvn.type(val);
1147  bool have_con = tcon->singleton();
1148  if (tval->singleton()) {
1149    if (!have_con) {
1150      // Swap, so constant is in con.
1151      con  = val;
1152      tcon = tval;
1153      val  = c->in(2);
1154      tval = _gvn.type(val);
1155      btest = BoolTest(btest).commute();
1156      have_con = true;
1157    } else {
1158      // Do we have two constants?  Then leave well enough alone.
1159      have_con = false;
1160    }
1161  }
1162  if (!have_con)                        // remaining adjustments need a con
1163    return;
1164
1165
1166  int val_in_map = map()->find_edge(val);
1167  if (val_in_map < 0)  return;          // replace_in_map would be useless
1168  {
1169    JVMState* jvms = this->jvms();
1170    if (!(jvms->is_loc(val_in_map) ||
1171          jvms->is_stk(val_in_map)))
1172      return;                           // again, it would be useless
1173  }
1174
1175  // Check for a comparison to a constant, and "know" that the compared
1176  // value is constrained on this path.
1177  assert(tcon->singleton(), "");
1178  ConstraintCastNode* ccast = NULL;
1179  Node* cast = NULL;
1180
1181  switch (btest) {
1182  case BoolTest::eq:                    // Constant test?
1183    {
1184      const Type* tboth = tcon->join(tval);
1185      if (tboth == tval)  break;        // Nothing to gain.
1186      if (tcon->isa_int()) {
1187        ccast = new (C, 2) CastIINode(val, tboth);
1188      } else if (tcon == TypePtr::NULL_PTR) {
1189        // Cast to null, but keep the pointer identity temporarily live.
1190        ccast = new (C, 2) CastPPNode(val, tboth);
1191      } else {
1192        const TypeF* tf = tcon->isa_float_constant();
1193        const TypeD* td = tcon->isa_double_constant();
1194        // Exclude tests vs float/double 0 as these could be
1195        // either +0 or -0.  Just because you are equal to +0
1196        // doesn't mean you ARE +0!
1197        if ((!tf || tf->_f != 0.0) &&
1198            (!td || td->_d != 0.0))
1199          cast = con;                   // Replace non-constant val by con.
1200      }
1201    }
1202    break;
1203
1204  case BoolTest::ne:
1205    if (tcon == TypePtr::NULL_PTR) {
1206      cast = cast_not_null(val, false);
1207    }
1208    break;
1209
1210  default:
1211    // (At this point we could record int range types with CastII.)
1212    break;
1213  }
1214
1215  if (ccast != NULL) {
1216    const Type* tcc = ccast->as_Type()->type();
1217    assert(tcc != tval && tcc->higher_equal(tval), "must improve");
1218    // Delay transform() call to allow recovery of pre-cast value
1219    // at the control merge.
1220    ccast->set_req(0, control());
1221    _gvn.set_type_bottom(ccast);
1222    record_for_igvn(ccast);
1223    cast = ccast;
1224  }
1225
1226  if (cast != NULL) {                   // Here's the payoff.
1227    replace_in_map(val, cast);
1228  }
1229}
1230
1231
1232//------------------------------do_one_bytecode--------------------------------
1233// Parse this bytecode, and alter the Parsers JVM->Node mapping
1234void Parse::do_one_bytecode() {
1235  Node *a, *b, *c, *d;          // Handy temps
1236  BoolTest::mask btest;
1237  int i;
1238
1239  assert(!has_exceptions(), "bytecode entry state must be clear of throws");
1240
1241  if (C->check_node_count(NodeLimitFudgeFactor * 5,
1242                          "out of nodes parsing method")) {
1243    return;
1244  }
1245
1246#ifdef ASSERT
1247  // for setting breakpoints
1248  if (TraceOptoParse) {
1249    tty->print(" @");
1250    dump_bci(bci());
1251  }
1252#endif
1253
1254  switch (bc()) {
1255  case Bytecodes::_nop:
1256    // do nothing
1257    break;
1258  case Bytecodes::_lconst_0:
1259    push_pair(longcon(0));
1260    break;
1261
1262  case Bytecodes::_lconst_1:
1263    push_pair(longcon(1));
1264    break;
1265
1266  case Bytecodes::_fconst_0:
1267    push(zerocon(T_FLOAT));
1268    break;
1269
1270  case Bytecodes::_fconst_1:
1271    push(makecon(TypeF::ONE));
1272    break;
1273
1274  case Bytecodes::_fconst_2:
1275    push(makecon(TypeF::make(2.0f)));
1276    break;
1277
1278  case Bytecodes::_dconst_0:
1279    push_pair(zerocon(T_DOUBLE));
1280    break;
1281
1282  case Bytecodes::_dconst_1:
1283    push_pair(makecon(TypeD::ONE));
1284    break;
1285
1286  case Bytecodes::_iconst_m1:push(intcon(-1)); break;
1287  case Bytecodes::_iconst_0: push(intcon( 0)); break;
1288  case Bytecodes::_iconst_1: push(intcon( 1)); break;
1289  case Bytecodes::_iconst_2: push(intcon( 2)); break;
1290  case Bytecodes::_iconst_3: push(intcon( 3)); break;
1291  case Bytecodes::_iconst_4: push(intcon( 4)); break;
1292  case Bytecodes::_iconst_5: push(intcon( 5)); break;
1293  case Bytecodes::_bipush:   push(intcon( iter().get_byte())); break;
1294  case Bytecodes::_sipush:   push(intcon( iter().get_short())); break;
1295  case Bytecodes::_aconst_null: push(null());  break;
1296  case Bytecodes::_ldc:
1297  case Bytecodes::_ldc_w:
1298  case Bytecodes::_ldc2_w:
1299    // If the constant is unresolved, run this BC once in the interpreter.
1300    if (iter().is_unresolved_string()) {
1301      uncommon_trap(Deoptimization::make_trap_request
1302                    (Deoptimization::Reason_unloaded,
1303                     Deoptimization::Action_reinterpret,
1304                     iter().get_constant_index()),
1305                    NULL, "unresolved_string");
1306      break;
1307    } else {
1308      ciConstant constant = iter().get_constant();
1309      if (constant.basic_type() == T_OBJECT) {
1310        ciObject* c = constant.as_object();
1311        if (c->is_klass()) {
1312          // The constant returned for a klass is the ciKlass for the
1313          // entry.  We want the java_mirror so get it.
1314          ciKlass* klass = c->as_klass();
1315          if (klass->is_loaded()) {
1316            constant = ciConstant(T_OBJECT, klass->java_mirror());
1317          } else {
1318            uncommon_trap(Deoptimization::make_trap_request
1319                          (Deoptimization::Reason_unloaded,
1320                           Deoptimization::Action_reinterpret,
1321                           iter().get_constant_index()),
1322                          NULL, "unresolved_klass");
1323            break;
1324          }
1325        }
1326      }
1327      push_constant(constant);
1328    }
1329
1330    break;
1331
1332  case Bytecodes::_aload_0:
1333    push( local(0) );
1334    break;
1335  case Bytecodes::_aload_1:
1336    push( local(1) );
1337    break;
1338  case Bytecodes::_aload_2:
1339    push( local(2) );
1340    break;
1341  case Bytecodes::_aload_3:
1342    push( local(3) );
1343    break;
1344  case Bytecodes::_aload:
1345    push( local(iter().get_index()) );
1346    break;
1347
1348  case Bytecodes::_fload_0:
1349  case Bytecodes::_iload_0:
1350    push( local(0) );
1351    break;
1352  case Bytecodes::_fload_1:
1353  case Bytecodes::_iload_1:
1354    push( local(1) );
1355    break;
1356  case Bytecodes::_fload_2:
1357  case Bytecodes::_iload_2:
1358    push( local(2) );
1359    break;
1360  case Bytecodes::_fload_3:
1361  case Bytecodes::_iload_3:
1362    push( local(3) );
1363    break;
1364  case Bytecodes::_fload:
1365  case Bytecodes::_iload:
1366    push( local(iter().get_index()) );
1367    break;
1368  case Bytecodes::_lload_0:
1369    push_pair_local( 0 );
1370    break;
1371  case Bytecodes::_lload_1:
1372    push_pair_local( 1 );
1373    break;
1374  case Bytecodes::_lload_2:
1375    push_pair_local( 2 );
1376    break;
1377  case Bytecodes::_lload_3:
1378    push_pair_local( 3 );
1379    break;
1380  case Bytecodes::_lload:
1381    push_pair_local( iter().get_index() );
1382    break;
1383
1384  case Bytecodes::_dload_0:
1385    push_pair_local(0);
1386    break;
1387  case Bytecodes::_dload_1:
1388    push_pair_local(1);
1389    break;
1390  case Bytecodes::_dload_2:
1391    push_pair_local(2);
1392    break;
1393  case Bytecodes::_dload_3:
1394    push_pair_local(3);
1395    break;
1396  case Bytecodes::_dload:
1397    push_pair_local(iter().get_index());
1398    break;
1399  case Bytecodes::_fstore_0:
1400  case Bytecodes::_istore_0:
1401  case Bytecodes::_astore_0:
1402    set_local( 0, pop() );
1403    break;
1404  case Bytecodes::_fstore_1:
1405  case Bytecodes::_istore_1:
1406  case Bytecodes::_astore_1:
1407    set_local( 1, pop() );
1408    break;
1409  case Bytecodes::_fstore_2:
1410  case Bytecodes::_istore_2:
1411  case Bytecodes::_astore_2:
1412    set_local( 2, pop() );
1413    break;
1414  case Bytecodes::_fstore_3:
1415  case Bytecodes::_istore_3:
1416  case Bytecodes::_astore_3:
1417    set_local( 3, pop() );
1418    break;
1419  case Bytecodes::_fstore:
1420  case Bytecodes::_istore:
1421  case Bytecodes::_astore:
1422    set_local( iter().get_index(), pop() );
1423    break;
1424  // long stores
1425  case Bytecodes::_lstore_0:
1426    set_pair_local( 0, pop_pair() );
1427    break;
1428  case Bytecodes::_lstore_1:
1429    set_pair_local( 1, pop_pair() );
1430    break;
1431  case Bytecodes::_lstore_2:
1432    set_pair_local( 2, pop_pair() );
1433    break;
1434  case Bytecodes::_lstore_3:
1435    set_pair_local( 3, pop_pair() );
1436    break;
1437  case Bytecodes::_lstore:
1438    set_pair_local( iter().get_index(), pop_pair() );
1439    break;
1440
1441  // double stores
1442  case Bytecodes::_dstore_0:
1443    set_pair_local( 0, dstore_rounding(pop_pair()) );
1444    break;
1445  case Bytecodes::_dstore_1:
1446    set_pair_local( 1, dstore_rounding(pop_pair()) );
1447    break;
1448  case Bytecodes::_dstore_2:
1449    set_pair_local( 2, dstore_rounding(pop_pair()) );
1450    break;
1451  case Bytecodes::_dstore_3:
1452    set_pair_local( 3, dstore_rounding(pop_pair()) );
1453    break;
1454  case Bytecodes::_dstore:
1455    set_pair_local( iter().get_index(), dstore_rounding(pop_pair()) );
1456    break;
1457
1458  case Bytecodes::_pop:  _sp -= 1;   break;
1459  case Bytecodes::_pop2: _sp -= 2;   break;
1460  case Bytecodes::_swap:
1461    a = pop();
1462    b = pop();
1463    push(a);
1464    push(b);
1465    break;
1466  case Bytecodes::_dup:
1467    a = pop();
1468    push(a);
1469    push(a);
1470    break;
1471  case Bytecodes::_dup_x1:
1472    a = pop();
1473    b = pop();
1474    push( a );
1475    push( b );
1476    push( a );
1477    break;
1478  case Bytecodes::_dup_x2:
1479    a = pop();
1480    b = pop();
1481    c = pop();
1482    push( a );
1483    push( c );
1484    push( b );
1485    push( a );
1486    break;
1487  case Bytecodes::_dup2:
1488    a = pop();
1489    b = pop();
1490    push( b );
1491    push( a );
1492    push( b );
1493    push( a );
1494    break;
1495
1496  case Bytecodes::_dup2_x1:
1497    // before: .. c, b, a
1498    // after:  .. b, a, c, b, a
1499    // not tested
1500    a = pop();
1501    b = pop();
1502    c = pop();
1503    push( b );
1504    push( a );
1505    push( c );
1506    push( b );
1507    push( a );
1508    break;
1509  case Bytecodes::_dup2_x2:
1510    // before: .. d, c, b, a
1511    // after:  .. b, a, d, c, b, a
1512    // not tested
1513    a = pop();
1514    b = pop();
1515    c = pop();
1516    d = pop();
1517    push( b );
1518    push( a );
1519    push( d );
1520    push( c );
1521    push( b );
1522    push( a );
1523    break;
1524
1525  case Bytecodes::_arraylength: {
1526    // Must do null-check with value on expression stack
1527    Node *ary = do_null_check(peek(), T_ARRAY);
1528    // Compile-time detect of null-exception?
1529    if (stopped())  return;
1530    a = pop();
1531    push(load_array_length(a));
1532    break;
1533  }
1534
1535  case Bytecodes::_baload: array_load(T_BYTE);   break;
1536  case Bytecodes::_caload: array_load(T_CHAR);   break;
1537  case Bytecodes::_iaload: array_load(T_INT);    break;
1538  case Bytecodes::_saload: array_load(T_SHORT);  break;
1539  case Bytecodes::_faload: array_load(T_FLOAT);  break;
1540  case Bytecodes::_aaload: array_load(T_OBJECT); break;
1541  case Bytecodes::_laload: {
1542    a = array_addressing(T_LONG, 0);
1543    if (stopped())  return;     // guarenteed null or range check
1544    _sp -= 2;                   // Pop array and index
1545    push_pair( make_load(control(), a, TypeLong::LONG, T_LONG, TypeAryPtr::LONGS));
1546    break;
1547  }
1548  case Bytecodes::_daload: {
1549    a = array_addressing(T_DOUBLE, 0);
1550    if (stopped())  return;     // guarenteed null or range check
1551    _sp -= 2;                   // Pop array and index
1552    push_pair( make_load(control(), a, Type::DOUBLE, T_DOUBLE, TypeAryPtr::DOUBLES));
1553    break;
1554  }
1555  case Bytecodes::_bastore: array_store(T_BYTE);  break;
1556  case Bytecodes::_castore: array_store(T_CHAR);  break;
1557  case Bytecodes::_iastore: array_store(T_INT);   break;
1558  case Bytecodes::_sastore: array_store(T_SHORT); break;
1559  case Bytecodes::_fastore: array_store(T_FLOAT); break;
1560  case Bytecodes::_aastore: {
1561    d = array_addressing(T_OBJECT, 1);
1562    if (stopped())  return;     // guarenteed null or range check
1563    array_store_check();
1564    c = pop();                  // Oop to store
1565    b = pop();                  // index (already used)
1566    a = pop();                  // the array itself
1567    const Type* elemtype  = _gvn.type(a)->is_aryptr()->elem();
1568    const TypeAryPtr* adr_type = TypeAryPtr::OOPS;
1569    Node* store = store_oop_to_array(control(), a, d, adr_type, c, elemtype, T_OBJECT);
1570    break;
1571  }
1572  case Bytecodes::_lastore: {
1573    a = array_addressing(T_LONG, 2);
1574    if (stopped())  return;     // guarenteed null or range check
1575    c = pop_pair();
1576    _sp -= 2;                   // Pop array and index
1577    store_to_memory(control(), a, c, T_LONG, TypeAryPtr::LONGS);
1578    break;
1579  }
1580  case Bytecodes::_dastore: {
1581    a = array_addressing(T_DOUBLE, 2);
1582    if (stopped())  return;     // guarenteed null or range check
1583    c = pop_pair();
1584    _sp -= 2;                   // Pop array and index
1585    c = dstore_rounding(c);
1586    store_to_memory(control(), a, c, T_DOUBLE, TypeAryPtr::DOUBLES);
1587    break;
1588  }
1589  case Bytecodes::_getfield:
1590    do_getfield();
1591    break;
1592
1593  case Bytecodes::_getstatic:
1594    do_getstatic();
1595    break;
1596
1597  case Bytecodes::_putfield:
1598    do_putfield();
1599    break;
1600
1601  case Bytecodes::_putstatic:
1602    do_putstatic();
1603    break;
1604
1605  case Bytecodes::_irem:
1606    do_irem();
1607    break;
1608  case Bytecodes::_idiv:
1609    // Must keep both values on the expression-stack during null-check
1610    do_null_check(peek(), T_INT);
1611    // Compile-time detect of null-exception?
1612    if (stopped())  return;
1613    b = pop();
1614    a = pop();
1615    push( _gvn.transform( new (C, 3) DivINode(control(),a,b) ) );
1616    break;
1617  case Bytecodes::_imul:
1618    b = pop(); a = pop();
1619    push( _gvn.transform( new (C, 3) MulINode(a,b) ) );
1620    break;
1621  case Bytecodes::_iadd:
1622    b = pop(); a = pop();
1623    push( _gvn.transform( new (C, 3) AddINode(a,b) ) );
1624    break;
1625  case Bytecodes::_ineg:
1626    a = pop();
1627    push( _gvn.transform( new (C, 3) SubINode(_gvn.intcon(0),a)) );
1628    break;
1629  case Bytecodes::_isub:
1630    b = pop(); a = pop();
1631    push( _gvn.transform( new (C, 3) SubINode(a,b) ) );
1632    break;
1633  case Bytecodes::_iand:
1634    b = pop(); a = pop();
1635    push( _gvn.transform( new (C, 3) AndINode(a,b) ) );
1636    break;
1637  case Bytecodes::_ior:
1638    b = pop(); a = pop();
1639    push( _gvn.transform( new (C, 3) OrINode(a,b) ) );
1640    break;
1641  case Bytecodes::_ixor:
1642    b = pop(); a = pop();
1643    push( _gvn.transform( new (C, 3) XorINode(a,b) ) );
1644    break;
1645  case Bytecodes::_ishl:
1646    b = pop(); a = pop();
1647    push( _gvn.transform( new (C, 3) LShiftINode(a,b) ) );
1648    break;
1649  case Bytecodes::_ishr:
1650    b = pop(); a = pop();
1651    push( _gvn.transform( new (C, 3) RShiftINode(a,b) ) );
1652    break;
1653  case Bytecodes::_iushr:
1654    b = pop(); a = pop();
1655    push( _gvn.transform( new (C, 3) URShiftINode(a,b) ) );
1656    break;
1657
1658  case Bytecodes::_fneg:
1659    a = pop();
1660    b = _gvn.transform(new (C, 2) NegFNode (a));
1661    push(b);
1662    break;
1663
1664  case Bytecodes::_fsub:
1665    b = pop();
1666    a = pop();
1667    c = _gvn.transform( new (C, 3) SubFNode(a,b) );
1668    d = precision_rounding(c);
1669    push( d );
1670    break;
1671
1672  case Bytecodes::_fadd:
1673    b = pop();
1674    a = pop();
1675    c = _gvn.transform( new (C, 3) AddFNode(a,b) );
1676    d = precision_rounding(c);
1677    push( d );
1678    break;
1679
1680  case Bytecodes::_fmul:
1681    b = pop();
1682    a = pop();
1683    c = _gvn.transform( new (C, 3) MulFNode(a,b) );
1684    d = precision_rounding(c);
1685    push( d );
1686    break;
1687
1688  case Bytecodes::_fdiv:
1689    b = pop();
1690    a = pop();
1691    c = _gvn.transform( new (C, 3) DivFNode(0,a,b) );
1692    d = precision_rounding(c);
1693    push( d );
1694    break;
1695
1696  case Bytecodes::_frem:
1697    if (Matcher::has_match_rule(Op_ModF)) {
1698      // Generate a ModF node.
1699      b = pop();
1700      a = pop();
1701      c = _gvn.transform( new (C, 3) ModFNode(0,a,b) );
1702      d = precision_rounding(c);
1703      push( d );
1704    }
1705    else {
1706      // Generate a call.
1707      modf();
1708    }
1709    break;
1710
1711  case Bytecodes::_fcmpl:
1712    b = pop();
1713    a = pop();
1714    c = _gvn.transform( new (C, 3) CmpF3Node( a, b));
1715    push(c);
1716    break;
1717  case Bytecodes::_fcmpg:
1718    b = pop();
1719    a = pop();
1720
1721    // Same as fcmpl but need to flip the unordered case.  Swap the inputs,
1722    // which negates the result sign except for unordered.  Flip the unordered
1723    // as well by using CmpF3 which implements unordered-lesser instead of
1724    // unordered-greater semantics.  Finally, commute the result bits.  Result
1725    // is same as using a CmpF3Greater except we did it with CmpF3 alone.
1726    c = _gvn.transform( new (C, 3) CmpF3Node( b, a));
1727    c = _gvn.transform( new (C, 3) SubINode(_gvn.intcon(0),c) );
1728    push(c);
1729    break;
1730
1731  case Bytecodes::_f2i:
1732    a = pop();
1733    push(_gvn.transform(new (C, 2) ConvF2INode(a)));
1734    break;
1735
1736  case Bytecodes::_d2i:
1737    a = pop_pair();
1738    b = _gvn.transform(new (C, 2) ConvD2INode(a));
1739    push( b );
1740    break;
1741
1742  case Bytecodes::_f2d:
1743    a = pop();
1744    b = _gvn.transform( new (C, 2) ConvF2DNode(a));
1745    push_pair( b );
1746    break;
1747
1748  case Bytecodes::_d2f:
1749    a = pop_pair();
1750    b = _gvn.transform( new (C, 2) ConvD2FNode(a));
1751    // This breaks _227_mtrt (speed & correctness) and _222_mpegaudio (speed)
1752    //b = _gvn.transform(new (C, 2) RoundFloatNode(0, b) );
1753    push( b );
1754    break;
1755
1756  case Bytecodes::_l2f:
1757    if (Matcher::convL2FSupported()) {
1758      a = pop_pair();
1759      b = _gvn.transform( new (C, 2) ConvL2FNode(a));
1760      // For i486.ad, FILD doesn't restrict precision to 24 or 53 bits.
1761      // Rather than storing the result into an FP register then pushing
1762      // out to memory to round, the machine instruction that implements
1763      // ConvL2D is responsible for rounding.
1764      // c = precision_rounding(b);
1765      c = _gvn.transform(b);
1766      push(c);
1767    } else {
1768      l2f();
1769    }
1770    break;
1771
1772  case Bytecodes::_l2d:
1773    a = pop_pair();
1774    b = _gvn.transform( new (C, 2) ConvL2DNode(a));
1775    // For i486.ad, rounding is always necessary (see _l2f above).
1776    // c = dprecision_rounding(b);
1777    c = _gvn.transform(b);
1778    push_pair(c);
1779    break;
1780
1781  case Bytecodes::_f2l:
1782    a = pop();
1783    b = _gvn.transform( new (C, 2) ConvF2LNode(a));
1784    push_pair(b);
1785    break;
1786
1787  case Bytecodes::_d2l:
1788    a = pop_pair();
1789    b = _gvn.transform( new (C, 2) ConvD2LNode(a));
1790    push_pair(b);
1791    break;
1792
1793  case Bytecodes::_dsub:
1794    b = pop_pair();
1795    a = pop_pair();
1796    c = _gvn.transform( new (C, 3) SubDNode(a,b) );
1797    d = dprecision_rounding(c);
1798    push_pair( d );
1799    break;
1800
1801  case Bytecodes::_dadd:
1802    b = pop_pair();
1803    a = pop_pair();
1804    c = _gvn.transform( new (C, 3) AddDNode(a,b) );
1805    d = dprecision_rounding(c);
1806    push_pair( d );
1807    break;
1808
1809  case Bytecodes::_dmul:
1810    b = pop_pair();
1811    a = pop_pair();
1812    c = _gvn.transform( new (C, 3) MulDNode(a,b) );
1813    d = dprecision_rounding(c);
1814    push_pair( d );
1815    break;
1816
1817  case Bytecodes::_ddiv:
1818    b = pop_pair();
1819    a = pop_pair();
1820    c = _gvn.transform( new (C, 3) DivDNode(0,a,b) );
1821    d = dprecision_rounding(c);
1822    push_pair( d );
1823    break;
1824
1825  case Bytecodes::_dneg:
1826    a = pop_pair();
1827    b = _gvn.transform(new (C, 2) NegDNode (a));
1828    push_pair(b);
1829    break;
1830
1831  case Bytecodes::_drem:
1832    if (Matcher::has_match_rule(Op_ModD)) {
1833      // Generate a ModD node.
1834      b = pop_pair();
1835      a = pop_pair();
1836      // a % b
1837
1838      c = _gvn.transform( new (C, 3) ModDNode(0,a,b) );
1839      d = dprecision_rounding(c);
1840      push_pair( d );
1841    }
1842    else {
1843      // Generate a call.
1844      modd();
1845    }
1846    break;
1847
1848  case Bytecodes::_dcmpl:
1849    b = pop_pair();
1850    a = pop_pair();
1851    c = _gvn.transform( new (C, 3) CmpD3Node( a, b));
1852    push(c);
1853    break;
1854
1855  case Bytecodes::_dcmpg:
1856    b = pop_pair();
1857    a = pop_pair();
1858    // Same as dcmpl but need to flip the unordered case.
1859    // Commute the inputs, which negates the result sign except for unordered.
1860    // Flip the unordered as well by using CmpD3 which implements
1861    // unordered-lesser instead of unordered-greater semantics.
1862    // Finally, negate the result bits.  Result is same as using a
1863    // CmpD3Greater except we did it with CmpD3 alone.
1864    c = _gvn.transform( new (C, 3) CmpD3Node( b, a));
1865    c = _gvn.transform( new (C, 3) SubINode(_gvn.intcon(0),c) );
1866    push(c);
1867    break;
1868
1869
1870    // Note for longs -> lo word is on TOS, hi word is on TOS - 1
1871  case Bytecodes::_land:
1872    b = pop_pair();
1873    a = pop_pair();
1874    c = _gvn.transform( new (C, 3) AndLNode(a,b) );
1875    push_pair(c);
1876    break;
1877  case Bytecodes::_lor:
1878    b = pop_pair();
1879    a = pop_pair();
1880    c = _gvn.transform( new (C, 3) OrLNode(a,b) );
1881    push_pair(c);
1882    break;
1883  case Bytecodes::_lxor:
1884    b = pop_pair();
1885    a = pop_pair();
1886    c = _gvn.transform( new (C, 3) XorLNode(a,b) );
1887    push_pair(c);
1888    break;
1889
1890  case Bytecodes::_lshl:
1891    b = pop();                  // the shift count
1892    a = pop_pair();             // value to be shifted
1893    c = _gvn.transform( new (C, 3) LShiftLNode(a,b) );
1894    push_pair(c);
1895    break;
1896  case Bytecodes::_lshr:
1897    b = pop();                  // the shift count
1898    a = pop_pair();             // value to be shifted
1899    c = _gvn.transform( new (C, 3) RShiftLNode(a,b) );
1900    push_pair(c);
1901    break;
1902  case Bytecodes::_lushr:
1903    b = pop();                  // the shift count
1904    a = pop_pair();             // value to be shifted
1905    c = _gvn.transform( new (C, 3) URShiftLNode(a,b) );
1906    push_pair(c);
1907    break;
1908  case Bytecodes::_lmul:
1909    b = pop_pair();
1910    a = pop_pair();
1911    c = _gvn.transform( new (C, 3) MulLNode(a,b) );
1912    push_pair(c);
1913    break;
1914
1915  case Bytecodes::_lrem:
1916    // Must keep both values on the expression-stack during null-check
1917    assert(peek(0) == top(), "long word order");
1918    do_null_check(peek(1), T_LONG);
1919    // Compile-time detect of null-exception?
1920    if (stopped())  return;
1921    b = pop_pair();
1922    a = pop_pair();
1923    c = _gvn.transform( new (C, 3) ModLNode(control(),a,b) );
1924    push_pair(c);
1925    break;
1926
1927  case Bytecodes::_ldiv:
1928    // Must keep both values on the expression-stack during null-check
1929    assert(peek(0) == top(), "long word order");
1930    do_null_check(peek(1), T_LONG);
1931    // Compile-time detect of null-exception?
1932    if (stopped())  return;
1933    b = pop_pair();
1934    a = pop_pair();
1935    c = _gvn.transform( new (C, 3) DivLNode(control(),a,b) );
1936    push_pair(c);
1937    break;
1938
1939  case Bytecodes::_ladd:
1940    b = pop_pair();
1941    a = pop_pair();
1942    c = _gvn.transform( new (C, 3) AddLNode(a,b) );
1943    push_pair(c);
1944    break;
1945  case Bytecodes::_lsub:
1946    b = pop_pair();
1947    a = pop_pair();
1948    c = _gvn.transform( new (C, 3) SubLNode(a,b) );
1949    push_pair(c);
1950    break;
1951  case Bytecodes::_lcmp:
1952    // Safepoints are now inserted _before_ branches.  The long-compare
1953    // bytecode painfully produces a 3-way value (-1,0,+1) which requires a
1954    // slew of control flow.  These are usually followed by a CmpI vs zero and
1955    // a branch; this pattern then optimizes to the obvious long-compare and
1956    // branch.  However, if the branch is backwards there's a Safepoint
1957    // inserted.  The inserted Safepoint captures the JVM state at the
1958    // pre-branch point, i.e. it captures the 3-way value.  Thus if a
1959    // long-compare is used to control a loop the debug info will force
1960    // computation of the 3-way value, even though the generated code uses a
1961    // long-compare and branch.  We try to rectify the situation by inserting
1962    // a SafePoint here and have it dominate and kill the safepoint added at a
1963    // following backwards branch.  At this point the JVM state merely holds 2
1964    // longs but not the 3-way value.
1965    if( UseLoopSafepoints ) {
1966      switch( iter().next_bc() ) {
1967      case Bytecodes::_ifgt:
1968      case Bytecodes::_iflt:
1969      case Bytecodes::_ifge:
1970      case Bytecodes::_ifle:
1971      case Bytecodes::_ifne:
1972      case Bytecodes::_ifeq:
1973        // If this is a backwards branch in the bytecodes, add Safepoint
1974        maybe_add_safepoint(iter().next_get_dest());
1975      }
1976    }
1977    b = pop_pair();
1978    a = pop_pair();
1979    c = _gvn.transform( new (C, 3) CmpL3Node( a, b ));
1980    push(c);
1981    break;
1982
1983  case Bytecodes::_lneg:
1984    a = pop_pair();
1985    b = _gvn.transform( new (C, 3) SubLNode(longcon(0),a));
1986    push_pair(b);
1987    break;
1988  case Bytecodes::_l2i:
1989    a = pop_pair();
1990    push( _gvn.transform( new (C, 2) ConvL2INode(a)));
1991    break;
1992  case Bytecodes::_i2l:
1993    a = pop();
1994    b = _gvn.transform( new (C, 2) ConvI2LNode(a));
1995    push_pair(b);
1996    break;
1997  case Bytecodes::_i2b:
1998    // Sign extend
1999    a = pop();
2000    a = _gvn.transform( new (C, 3) LShiftINode(a,_gvn.intcon(24)) );
2001    a = _gvn.transform( new (C, 3) RShiftINode(a,_gvn.intcon(24)) );
2002    push( a );
2003    break;
2004  case Bytecodes::_i2s:
2005    a = pop();
2006    a = _gvn.transform( new (C, 3) LShiftINode(a,_gvn.intcon(16)) );
2007    a = _gvn.transform( new (C, 3) RShiftINode(a,_gvn.intcon(16)) );
2008    push( a );
2009    break;
2010  case Bytecodes::_i2c:
2011    a = pop();
2012    push( _gvn.transform( new (C, 3) AndINode(a,_gvn.intcon(0xFFFF)) ) );
2013    break;
2014
2015  case Bytecodes::_i2f:
2016    a = pop();
2017    b = _gvn.transform( new (C, 2) ConvI2FNode(a) ) ;
2018    c = precision_rounding(b);
2019    push (b);
2020    break;
2021
2022  case Bytecodes::_i2d:
2023    a = pop();
2024    b = _gvn.transform( new (C, 2) ConvI2DNode(a));
2025    push_pair(b);
2026    break;
2027
2028  case Bytecodes::_iinc:        // Increment local
2029    i = iter().get_index();     // Get local index
2030    set_local( i, _gvn.transform( new (C, 3) AddINode( _gvn.intcon(iter().get_iinc_con()), local(i) ) ) );
2031    break;
2032
2033  // Exit points of synchronized methods must have an unlock node
2034  case Bytecodes::_return:
2035    return_current(NULL);
2036    break;
2037
2038  case Bytecodes::_ireturn:
2039  case Bytecodes::_areturn:
2040  case Bytecodes::_freturn:
2041    return_current(pop());
2042    break;
2043  case Bytecodes::_lreturn:
2044    return_current(pop_pair());
2045    break;
2046  case Bytecodes::_dreturn:
2047    return_current(pop_pair());
2048    break;
2049
2050  case Bytecodes::_athrow:
2051    // null exception oop throws NULL pointer exception
2052    do_null_check(peek(), T_OBJECT);
2053    if (stopped())  return;
2054    if (JvmtiExport::can_post_exceptions()) {
2055      // "Full-speed throwing" is not necessary here,
2056      // since we're notifying the VM on every throw.
2057      uncommon_trap(Deoptimization::Reason_unhandled,
2058                    Deoptimization::Action_none);
2059      return;
2060    }
2061    // Hook the thrown exception directly to subsequent handlers.
2062    if (BailoutToInterpreterForThrows) {
2063      // Keep method interpreted from now on.
2064      uncommon_trap(Deoptimization::Reason_unhandled,
2065                    Deoptimization::Action_make_not_compilable);
2066      return;
2067    }
2068    add_exception_state(make_exception_state(peek()));
2069    break;
2070
2071  case Bytecodes::_goto:   // fall through
2072  case Bytecodes::_goto_w: {
2073    int target_bci = (bc() == Bytecodes::_goto) ? iter().get_dest() : iter().get_far_dest();
2074
2075    // If this is a backwards branch in the bytecodes, add Safepoint
2076    maybe_add_safepoint(target_bci);
2077
2078    // Update method data
2079    profile_taken_branch(target_bci);
2080
2081    // Merge the current control into the target basic block
2082    merge(target_bci);
2083
2084    // See if we can get some profile data and hand it off to the next block
2085    Block *target_block = block()->successor_for_bci(target_bci);
2086    if (target_block->pred_count() != 1)  break;
2087    ciMethodData* methodData = method()->method_data();
2088    if (!methodData->is_mature())  break;
2089    ciProfileData* data = methodData->bci_to_data(bci());
2090    assert( data->is_JumpData(), "" );
2091    int taken = ((ciJumpData*)data)->taken();
2092    taken = method()->scale_count(taken);
2093    target_block->set_count(taken);
2094    break;
2095  }
2096
2097  case Bytecodes::_ifnull:
2098    do_ifnull(BoolTest::eq);
2099    break;
2100  case Bytecodes::_ifnonnull:
2101    do_ifnull(BoolTest::ne);
2102    break;
2103
2104  case Bytecodes::_if_acmpeq: btest = BoolTest::eq; goto handle_if_acmp;
2105  case Bytecodes::_if_acmpne: btest = BoolTest::ne; goto handle_if_acmp;
2106  handle_if_acmp:
2107    // If this is a backwards branch in the bytecodes, add Safepoint
2108    maybe_add_safepoint(iter().get_dest());
2109    a = pop();
2110    b = pop();
2111    c = _gvn.transform( new (C, 3) CmpPNode(b, a) );
2112    do_if(btest, c);
2113    break;
2114
2115  case Bytecodes::_ifeq: btest = BoolTest::eq; goto handle_ifxx;
2116  case Bytecodes::_ifne: btest = BoolTest::ne; goto handle_ifxx;
2117  case Bytecodes::_iflt: btest = BoolTest::lt; goto handle_ifxx;
2118  case Bytecodes::_ifle: btest = BoolTest::le; goto handle_ifxx;
2119  case Bytecodes::_ifgt: btest = BoolTest::gt; goto handle_ifxx;
2120  case Bytecodes::_ifge: btest = BoolTest::ge; goto handle_ifxx;
2121  handle_ifxx:
2122    // If this is a backwards branch in the bytecodes, add Safepoint
2123    maybe_add_safepoint(iter().get_dest());
2124    a = _gvn.intcon(0);
2125    b = pop();
2126    c = _gvn.transform( new (C, 3) CmpINode(b, a) );
2127    do_if(btest, c);
2128    break;
2129
2130  case Bytecodes::_if_icmpeq: btest = BoolTest::eq; goto handle_if_icmp;
2131  case Bytecodes::_if_icmpne: btest = BoolTest::ne; goto handle_if_icmp;
2132  case Bytecodes::_if_icmplt: btest = BoolTest::lt; goto handle_if_icmp;
2133  case Bytecodes::_if_icmple: btest = BoolTest::le; goto handle_if_icmp;
2134  case Bytecodes::_if_icmpgt: btest = BoolTest::gt; goto handle_if_icmp;
2135  case Bytecodes::_if_icmpge: btest = BoolTest::ge; goto handle_if_icmp;
2136  handle_if_icmp:
2137    // If this is a backwards branch in the bytecodes, add Safepoint
2138    maybe_add_safepoint(iter().get_dest());
2139    a = pop();
2140    b = pop();
2141    c = _gvn.transform( new (C, 3) CmpINode( b, a ) );
2142    do_if(btest, c);
2143    break;
2144
2145  case Bytecodes::_tableswitch:
2146    do_tableswitch();
2147    break;
2148
2149  case Bytecodes::_lookupswitch:
2150    do_lookupswitch();
2151    break;
2152
2153  case Bytecodes::_invokestatic:
2154  case Bytecodes::_invokespecial:
2155  case Bytecodes::_invokevirtual:
2156  case Bytecodes::_invokeinterface:
2157    do_call();
2158    break;
2159  case Bytecodes::_checkcast:
2160    do_checkcast();
2161    break;
2162  case Bytecodes::_instanceof:
2163    do_instanceof();
2164    break;
2165  case Bytecodes::_anewarray:
2166    do_anewarray();
2167    break;
2168  case Bytecodes::_newarray:
2169    do_newarray((BasicType)iter().get_index());
2170    break;
2171  case Bytecodes::_multianewarray:
2172    do_multianewarray();
2173    break;
2174  case Bytecodes::_new:
2175    do_new();
2176    break;
2177
2178  case Bytecodes::_jsr:
2179  case Bytecodes::_jsr_w:
2180    do_jsr();
2181    break;
2182
2183  case Bytecodes::_ret:
2184    do_ret();
2185    break;
2186
2187
2188  case Bytecodes::_monitorenter:
2189    do_monitor_enter();
2190    break;
2191
2192  case Bytecodes::_monitorexit:
2193    do_monitor_exit();
2194    break;
2195
2196  case Bytecodes::_breakpoint:
2197    // Breakpoint set concurrently to compile
2198    // %%% use an uncommon trap?
2199    C->record_failure("breakpoint in method");
2200    return;
2201
2202  default:
2203#ifndef PRODUCT
2204    map()->dump(99);
2205#endif
2206    tty->print("\nUnhandled bytecode %s\n", Bytecodes::name(bc()) );
2207    ShouldNotReachHere();
2208  }
2209
2210#ifndef PRODUCT
2211  IdealGraphPrinter *printer = IdealGraphPrinter::printer();
2212  if(printer) {
2213    char buffer[256];
2214    sprintf(buffer, "Bytecode %d: %s", bci(), Bytecodes::name(bc()));
2215    bool old = printer->traverse_outs();
2216    printer->set_traverse_outs(true);
2217    printer->print_method(C, buffer, 3);
2218    printer->set_traverse_outs(old);
2219  }
2220#endif
2221}
2222