1 /*
2  * Copyright (c) 1998, 2018, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
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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).
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15  * You should have received a copy of the GNU General Public License version
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17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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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/resourceArea.hpp"
32 #include "memory/universe.hpp"
33 #include "oops/oop.inline.hpp"
34 #include "opto/addnode.hpp"
35 #include "opto/castnode.hpp"
36 #include "opto/convertnode.hpp"
37 #include "opto/divnode.hpp"
38 #include "opto/idealGraphPrinter.hpp"
39 #include "opto/matcher.hpp"
40 #include "opto/memnode.hpp"
41 #include "opto/mulnode.hpp"
42 #include "opto/opaquenode.hpp"
43 #include "opto/parse.hpp"
44 #include "opto/runtime.hpp"
45 #include "runtime/deoptimization.hpp"
46 #include "runtime/sharedRuntime.hpp"
47 
48 #ifndef PRODUCT
49 extern int explicit_null_checks_inserted,
50            explicit_null_checks_elided;
51 #endif
52 
53 //---------------------------------array_load----------------------------------
array_load(BasicType bt)54 void Parse::array_load(BasicType bt) {
55   const Type* elemtype = Type::TOP;
56   bool big_val = bt == T_DOUBLE || bt == T_LONG;
57   Node* adr = array_addressing(bt, 0, elemtype);
58   if (stopped())  return;     // guaranteed null or range check
59 
60   pop();                      // index (already used)
61   Node* array = pop();        // the array itself
62 
63   if (elemtype == TypeInt::BOOL) {
64     bt = T_BOOLEAN;
65   }
66   const TypeAryPtr* adr_type = TypeAryPtr::get_array_body_type(bt);
67 
68   Node* ld = access_load_at(array, adr, adr_type, elemtype, bt,
69                             IN_HEAP | IS_ARRAY | C2_CONTROL_DEPENDENT_LOAD);
70   if (big_val) {
71     push_pair(ld);
72   } else {
73     push(ld);
74   }
75 }
76 
77 
78 //--------------------------------array_store----------------------------------
array_store(BasicType bt)79 void Parse::array_store(BasicType bt) {
80   const Type* elemtype = Type::TOP;
81   bool big_val = bt == T_DOUBLE || bt == T_LONG;
82   Node* adr = array_addressing(bt, big_val ? 2 : 1, elemtype);
83   if (stopped())  return;     // guaranteed null or range check
84   if (bt == T_OBJECT) {
85     array_store_check();
86   }
87   Node* val;                  // Oop to store
88   if (big_val) {
89     val = pop_pair();
90   } else {
91     val = pop();
92   }
93   pop();                      // index (already used)
94   Node* array = pop();        // the array itself
95 
96   if (elemtype == TypeInt::BOOL) {
97     bt = T_BOOLEAN;
98   }
99   const TypeAryPtr* adr_type = TypeAryPtr::get_array_body_type(bt);
100 
101   access_store_at(array, adr, adr_type, val, elemtype, bt, MO_UNORDERED | IN_HEAP | IS_ARRAY);
102 }
103 
104 
105 //------------------------------array_addressing-------------------------------
106 // Pull array and index from the stack.  Compute pointer-to-element.
array_addressing(BasicType type,int vals,const Type * & elemtype)107 Node* Parse::array_addressing(BasicType type, int vals, const Type*& elemtype) {
108   Node *idx   = peek(0+vals);   // Get from stack without popping
109   Node *ary   = peek(1+vals);   // in case of exception
110 
111   // Null check the array base, with correct stack contents
112   ary = null_check(ary, T_ARRAY);
113   // Compile-time detect of null-exception?
114   if (stopped())  return top();
115 
116   const TypeAryPtr* arytype  = _gvn.type(ary)->is_aryptr();
117   const TypeInt*    sizetype = arytype->size();
118   elemtype = arytype->elem();
119 
120   if (UseUniqueSubclasses) {
121     const Type* el = elemtype->make_ptr();
122     if (el && el->isa_instptr()) {
123       const TypeInstPtr* toop = el->is_instptr();
124       if (toop->klass()->as_instance_klass()->unique_concrete_subklass()) {
125         // If we load from "AbstractClass[]" we must see "ConcreteSubClass".
126         const Type* subklass = Type::get_const_type(toop->klass());
127         elemtype = subklass->join_speculative(el);
128       }
129     }
130   }
131 
132   // Check for big class initializers with all constant offsets
133   // feeding into a known-size array.
134   const TypeInt* idxtype = _gvn.type(idx)->is_int();
135   // See if the highest idx value is less than the lowest array bound,
136   // and if the idx value cannot be negative:
137   bool need_range_check = true;
138   if (idxtype->_hi < sizetype->_lo && idxtype->_lo >= 0) {
139     need_range_check = false;
140     if (C->log() != NULL)   C->log()->elem("observe that='!need_range_check'");
141   }
142 
143   ciKlass * arytype_klass = arytype->klass();
144   if ((arytype_klass != NULL) && (!arytype_klass->is_loaded())) {
145     // Only fails for some -Xcomp runs
146     // The class is unloaded.  We have to run this bytecode in the interpreter.
147     uncommon_trap(Deoptimization::Reason_unloaded,
148                   Deoptimization::Action_reinterpret,
149                   arytype->klass(), "!loaded array");
150     return top();
151   }
152 
153   // Do the range check
154   if (GenerateRangeChecks && need_range_check) {
155     Node* tst;
156     if (sizetype->_hi <= 0) {
157       // The greatest array bound is negative, so we can conclude that we're
158       // compiling unreachable code, but the unsigned compare trick used below
159       // only works with non-negative lengths.  Instead, hack "tst" to be zero so
160       // the uncommon_trap path will always be taken.
161       tst = _gvn.intcon(0);
162     } else {
163       // Range is constant in array-oop, so we can use the original state of mem
164       Node* len = load_array_length(ary);
165 
166       // Test length vs index (standard trick using unsigned compare)
167       Node* chk = _gvn.transform( new CmpUNode(idx, len) );
168       BoolTest::mask btest = BoolTest::lt;
169       tst = _gvn.transform( new BoolNode(chk, btest) );
170     }
171     RangeCheckNode* rc = new RangeCheckNode(control(), tst, PROB_MAX, COUNT_UNKNOWN);
172     _gvn.set_type(rc, rc->Value(&_gvn));
173     if (!tst->is_Con()) {
174       record_for_igvn(rc);
175     }
176     set_control(_gvn.transform(new IfTrueNode(rc)));
177     // Branch to failure if out of bounds
178     {
179       PreserveJVMState pjvms(this);
180       set_control(_gvn.transform(new IfFalseNode(rc)));
181       if (C->allow_range_check_smearing()) {
182         // Do not use builtin_throw, since range checks are sometimes
183         // made more stringent by an optimistic transformation.
184         // This creates "tentative" range checks at this point,
185         // which are not guaranteed to throw exceptions.
186         // See IfNode::Ideal, is_range_check, adjust_check.
187         uncommon_trap(Deoptimization::Reason_range_check,
188                       Deoptimization::Action_make_not_entrant,
189                       NULL, "range_check");
190       } else {
191         // If we have already recompiled with the range-check-widening
192         // heroic optimization turned off, then we must really be throwing
193         // range check exceptions.
194         builtin_throw(Deoptimization::Reason_range_check, idx);
195       }
196     }
197   }
198   // Check for always knowing you are throwing a range-check exception
199   if (stopped())  return top();
200 
201   // Make array address computation control dependent to prevent it
202   // from floating above the range check during loop optimizations.
203   Node* ptr = array_element_address(ary, idx, type, sizetype, control());
204   assert(ptr != top(), "top should go hand-in-hand with stopped");
205 
206   return ptr;
207 }
208 
209 
210 // returns IfNode
jump_if_fork_int(Node * a,Node * b,BoolTest::mask mask,float prob,float cnt)211 IfNode* Parse::jump_if_fork_int(Node* a, Node* b, BoolTest::mask mask, float prob, float cnt) {
212   Node   *cmp = _gvn.transform(new CmpINode(a, b)); // two cases: shiftcount > 32 and shiftcount <= 32
213   Node   *tst = _gvn.transform(new BoolNode(cmp, mask));
214   IfNode *iff = create_and_map_if(control(), tst, prob, cnt);
215   return iff;
216 }
217 
218 // return Region node
jump_if_join(Node * iffalse,Node * iftrue)219 Node* Parse::jump_if_join(Node* iffalse, Node* iftrue) {
220   Node *region  = new RegionNode(3); // 2 results
221   record_for_igvn(region);
222   region->init_req(1, iffalse);
223   region->init_req(2, iftrue );
224   _gvn.set_type(region, Type::CONTROL);
225   region = _gvn.transform(region);
226   set_control (region);
227   return region;
228 }
229 
230 // sentinel value for the target bci to mark never taken branches
231 // (according to profiling)
232 static const int never_reached = INT_MAX;
233 
234 //------------------------------helper for tableswitch-------------------------
jump_if_true_fork(IfNode * iff,int dest_bci_if_true,int prof_table_index,bool unc)235 void Parse::jump_if_true_fork(IfNode *iff, int dest_bci_if_true, int prof_table_index, bool unc) {
236   // True branch, use existing map info
237   { PreserveJVMState pjvms(this);
238     Node *iftrue  = _gvn.transform( new IfTrueNode (iff) );
239     set_control( iftrue );
240     if (unc) {
241       repush_if_args();
242       uncommon_trap(Deoptimization::Reason_unstable_if,
243                     Deoptimization::Action_reinterpret,
244                     NULL,
245                     "taken always");
246     } else {
247       assert(dest_bci_if_true != never_reached, "inconsistent dest");
248       profile_switch_case(prof_table_index);
249       merge_new_path(dest_bci_if_true);
250     }
251   }
252 
253   // False branch
254   Node *iffalse = _gvn.transform( new IfFalseNode(iff) );
255   set_control( iffalse );
256 }
257 
jump_if_false_fork(IfNode * iff,int dest_bci_if_true,int prof_table_index,bool unc)258 void Parse::jump_if_false_fork(IfNode *iff, int dest_bci_if_true, int prof_table_index, bool unc) {
259   // True branch, use existing map info
260   { PreserveJVMState pjvms(this);
261     Node *iffalse  = _gvn.transform( new IfFalseNode (iff) );
262     set_control( iffalse );
263     if (unc) {
264       repush_if_args();
265       uncommon_trap(Deoptimization::Reason_unstable_if,
266                     Deoptimization::Action_reinterpret,
267                     NULL,
268                     "taken never");
269     } else {
270       assert(dest_bci_if_true != never_reached, "inconsistent dest");
271       profile_switch_case(prof_table_index);
272       merge_new_path(dest_bci_if_true);
273     }
274   }
275 
276   // False branch
277   Node *iftrue = _gvn.transform( new IfTrueNode(iff) );
278   set_control( iftrue );
279 }
280 
jump_if_always_fork(int dest_bci,int prof_table_index,bool unc)281 void Parse::jump_if_always_fork(int dest_bci, int prof_table_index, bool unc) {
282   // False branch, use existing map and control()
283   if (unc) {
284     repush_if_args();
285     uncommon_trap(Deoptimization::Reason_unstable_if,
286                   Deoptimization::Action_reinterpret,
287                   NULL,
288                   "taken never");
289   } else {
290     assert(dest_bci != never_reached, "inconsistent dest");
291     profile_switch_case(prof_table_index);
292     merge_new_path(dest_bci);
293   }
294 }
295 
296 
297 extern "C" {
jint_cmp(const void * i,const void * j)298   static int jint_cmp(const void *i, const void *j) {
299     int a = *(jint *)i;
300     int b = *(jint *)j;
301     return a > b ? 1 : a < b ? -1 : 0;
302   }
303 }
304 
305 
306 // Default value for methodData switch indexing. Must be a negative value to avoid
307 // conflict with any legal switch index.
308 #define NullTableIndex -1
309 
310 class SwitchRange : public StackObj {
311   // a range of integers coupled with a bci destination
312   jint _lo;                     // inclusive lower limit
313   jint _hi;                     // inclusive upper limit
314   int _dest;
315   int _table_index;             // index into method data table
316   float _cnt;                   // how many times this range was hit according to profiling
317 
318 public:
lo() const319   jint lo() const              { return _lo;   }
hi() const320   jint hi() const              { return _hi;   }
dest() const321   int  dest() const            { return _dest; }
table_index() const322   int  table_index() const     { return _table_index; }
is_singleton() const323   bool is_singleton() const    { return _lo == _hi; }
cnt() const324   float cnt() const            { return _cnt; }
325 
setRange(jint lo,jint hi,int dest,int table_index,float cnt)326   void setRange(jint lo, jint hi, int dest, int table_index, float cnt) {
327     assert(lo <= hi, "must be a non-empty range");
328     _lo = lo, _hi = hi; _dest = dest; _table_index = table_index; _cnt = cnt;
329     assert(_cnt >= 0, "");
330   }
adjoinRange(jint lo,jint hi,int dest,int table_index,float cnt,bool trim_ranges)331   bool adjoinRange(jint lo, jint hi, int dest, int table_index, float cnt, bool trim_ranges) {
332     assert(lo <= hi, "must be a non-empty range");
333     if (lo == _hi+1 && table_index == _table_index) {
334       // see merge_ranges() comment below
335       if (trim_ranges) {
336         if (cnt == 0) {
337           if (_cnt != 0) {
338             return false;
339           }
340           if (dest != _dest) {
341             _dest = never_reached;
342           }
343         } else {
344           if (_cnt == 0) {
345             return false;
346           }
347           if (dest != _dest) {
348             return false;
349           }
350         }
351       } else {
352         if (dest != _dest) {
353           return false;
354         }
355       }
356       _hi = hi;
357       _cnt += cnt;
358       return true;
359     }
360     return false;
361   }
362 
set(jint value,int dest,int table_index,float cnt)363   void set (jint value, int dest, int table_index, float cnt) {
364     setRange(value, value, dest, table_index, cnt);
365   }
adjoin(jint value,int dest,int table_index,float cnt,bool trim_ranges)366   bool adjoin(jint value, int dest, int table_index, float cnt, bool trim_ranges) {
367     return adjoinRange(value, value, dest, table_index, cnt, trim_ranges);
368   }
adjoin(SwitchRange & other)369   bool adjoin(SwitchRange& other) {
370     return adjoinRange(other._lo, other._hi, other._dest, other._table_index, other._cnt, false);
371   }
372 
print()373   void print() {
374     if (is_singleton())
375       tty->print(" {%d}=>%d (cnt=%f)", lo(), dest(), cnt());
376     else if (lo() == min_jint)
377       tty->print(" {..%d}=>%d (cnt=%f)", hi(), dest(), cnt());
378     else if (hi() == max_jint)
379       tty->print(" {%d..}=>%d (cnt=%f)", lo(), dest(), cnt());
380     else
381       tty->print(" {%d..%d}=>%d (cnt=%f)", lo(), hi(), dest(), cnt());
382   }
383 };
384 
385 // We try to minimize the number of ranges and the size of the taken
386 // ones using profiling data. When ranges are created,
387 // SwitchRange::adjoinRange() only allows 2 adjoining ranges to merge
388 // if both were never hit or both were hit to build longer unreached
389 // ranges. Here, we now merge adjoining ranges with the same
390 // destination and finally set destination of unreached ranges to the
391 // special value never_reached because it can help minimize the number
392 // of tests that are necessary.
393 //
394 // For instance:
395 // [0, 1] to target1 sometimes taken
396 // [1, 2] to target1 never taken
397 // [2, 3] to target2 never taken
398 // would lead to:
399 // [0, 1] to target1 sometimes taken
400 // [1, 3] never taken
401 //
402 // (first 2 ranges to target1 are not merged)
merge_ranges(SwitchRange * ranges,int & rp)403 static void merge_ranges(SwitchRange* ranges, int& rp) {
404   if (rp == 0) {
405     return;
406   }
407   int shift = 0;
408   for (int j = 0; j < rp; j++) {
409     SwitchRange& r1 = ranges[j-shift];
410     SwitchRange& r2 = ranges[j+1];
411     if (r1.adjoin(r2)) {
412       shift++;
413     } else if (shift > 0) {
414       ranges[j+1-shift] = r2;
415     }
416   }
417   rp -= shift;
418   for (int j = 0; j <= rp; j++) {
419     SwitchRange& r = ranges[j];
420     if (r.cnt() == 0 && r.dest() != never_reached) {
421       r.setRange(r.lo(), r.hi(), never_reached, r.table_index(), r.cnt());
422     }
423   }
424 }
425 
426 //-------------------------------do_tableswitch--------------------------------
do_tableswitch()427 void Parse::do_tableswitch() {
428   Node* lookup = pop();
429   // Get information about tableswitch
430   int default_dest = iter().get_dest_table(0);
431   int lo_index     = iter().get_int_table(1);
432   int hi_index     = iter().get_int_table(2);
433   int len          = hi_index - lo_index + 1;
434 
435   if (len < 1) {
436     // If this is a backward branch, add safepoint
437     maybe_add_safepoint(default_dest);
438     merge(default_dest);
439     return;
440   }
441 
442   ciMethodData* methodData = method()->method_data();
443   ciMultiBranchData* profile = NULL;
444   if (methodData->is_mature() && UseSwitchProfiling) {
445     ciProfileData* data = methodData->bci_to_data(bci());
446     if (data != NULL && data->is_MultiBranchData()) {
447       profile = (ciMultiBranchData*)data;
448     }
449   }
450   bool trim_ranges = !method_data_update() && !C->too_many_traps(method(), bci(), Deoptimization::Reason_unstable_if);
451 
452   // generate decision tree, using trichotomy when possible
453   int rnum = len+2;
454   bool makes_backward_branch = false;
455   SwitchRange* ranges = NEW_RESOURCE_ARRAY(SwitchRange, rnum);
456   int rp = -1;
457   if (lo_index != min_jint) {
458     uint cnt = 1;
459     if (profile != NULL) {
460       cnt = profile->default_count() / (hi_index != max_jint ? 2 : 1);
461     }
462     ranges[++rp].setRange(min_jint, lo_index-1, default_dest, NullTableIndex, cnt);
463   }
464   for (int j = 0; j < len; j++) {
465     jint match_int = lo_index+j;
466     int  dest      = iter().get_dest_table(j+3);
467     makes_backward_branch |= (dest <= bci());
468     int  table_index = method_data_update() ? j : NullTableIndex;
469     uint cnt = 1;
470     if (profile != NULL) {
471       cnt = profile->count_at(j);
472     }
473     if (rp < 0 || !ranges[rp].adjoin(match_int, dest, table_index, cnt, trim_ranges)) {
474       ranges[++rp].set(match_int, dest, table_index, cnt);
475     }
476   }
477   jint highest = lo_index+(len-1);
478   assert(ranges[rp].hi() == highest, "");
479   if (highest != max_jint) {
480     uint cnt = 1;
481     if (profile != NULL) {
482       cnt = profile->default_count() / (lo_index != min_jint ? 2 : 1);
483     }
484     if (!ranges[rp].adjoinRange(highest+1, max_jint, default_dest, NullTableIndex, cnt, trim_ranges)) {
485       ranges[++rp].setRange(highest+1, max_jint, default_dest, NullTableIndex, cnt);
486     }
487   }
488   assert(rp < len+2, "not too many ranges");
489 
490   if (trim_ranges) {
491     merge_ranges(ranges, rp);
492   }
493 
494   // Safepoint in case if backward branch observed
495   if( makes_backward_branch && UseLoopSafepoints )
496     add_safepoint();
497 
498   jump_switch_ranges(lookup, &ranges[0], &ranges[rp]);
499 }
500 
501 
502 //------------------------------do_lookupswitch--------------------------------
do_lookupswitch()503 void Parse::do_lookupswitch() {
504   Node *lookup = pop();         // lookup value
505   // Get information about lookupswitch
506   int default_dest = iter().get_dest_table(0);
507   int len          = iter().get_int_table(1);
508 
509   if (len < 1) {    // If this is a backward branch, add safepoint
510     maybe_add_safepoint(default_dest);
511     merge(default_dest);
512     return;
513   }
514 
515   ciMethodData* methodData = method()->method_data();
516   ciMultiBranchData* profile = NULL;
517   if (methodData->is_mature() && UseSwitchProfiling) {
518     ciProfileData* data = methodData->bci_to_data(bci());
519     if (data != NULL && data->is_MultiBranchData()) {
520       profile = (ciMultiBranchData*)data;
521     }
522   }
523   bool trim_ranges = !method_data_update() && !C->too_many_traps(method(), bci(), Deoptimization::Reason_unstable_if);
524 
525   // generate decision tree, using trichotomy when possible
526   jint* table = NEW_RESOURCE_ARRAY(jint, len*3);
527   {
528     for (int j = 0; j < len; j++) {
529       table[3*j+0] = iter().get_int_table(2+2*j);
530       table[3*j+1] = iter().get_dest_table(2+2*j+1);
531       table[3*j+2] = profile == NULL ? 1 : profile->count_at(j);
532     }
533     qsort(table, len, 3*sizeof(table[0]), jint_cmp);
534   }
535 
536   float defaults = 0;
537   jint prev = min_jint;
538   for (int j = 0; j < len; j++) {
539     jint match_int = table[3*j+0];
540     if (match_int != prev) {
541       defaults += (float)match_int - prev;
542     }
543     prev = match_int+1;
544   }
545   if (prev-1 != max_jint) {
546     defaults += (float)max_jint - prev + 1;
547   }
548   float default_cnt = 1;
549   if (profile != NULL) {
550     default_cnt = profile->default_count()/defaults;
551   }
552 
553   int rnum = len*2+1;
554   bool makes_backward_branch = false;
555   SwitchRange* ranges = NEW_RESOURCE_ARRAY(SwitchRange, rnum);
556   int rp = -1;
557   for (int j = 0; j < len; j++) {
558     jint match_int   = table[3*j+0];
559     int  dest        = table[3*j+1];
560     int  cnt         = table[3*j+2];
561     int  next_lo     = rp < 0 ? min_jint : ranges[rp].hi()+1;
562     int  table_index = method_data_update() ? j : NullTableIndex;
563     makes_backward_branch |= (dest <= bci());
564     float c = default_cnt * ((float)match_int - next_lo);
565     if (match_int != next_lo && (rp < 0 || !ranges[rp].adjoinRange(next_lo, match_int-1, default_dest, NullTableIndex, c, trim_ranges))) {
566       assert(default_dest != never_reached, "sentinel value for dead destinations");
567       ranges[++rp].setRange(next_lo, match_int-1, default_dest, NullTableIndex, c);
568     }
569     if (rp < 0 || !ranges[rp].adjoin(match_int, dest, table_index, cnt, trim_ranges)) {
570       assert(dest != never_reached, "sentinel value for dead destinations");
571       ranges[++rp].set(match_int, dest, table_index, cnt);
572     }
573   }
574   jint highest = table[3*(len-1)];
575   assert(ranges[rp].hi() == highest, "");
576   if (highest != max_jint &&
577       !ranges[rp].adjoinRange(highest+1, max_jint, default_dest, NullTableIndex, default_cnt * ((float)max_jint - highest), trim_ranges)) {
578     ranges[++rp].setRange(highest+1, max_jint, default_dest, NullTableIndex, default_cnt * ((float)max_jint - highest));
579   }
580   assert(rp < rnum, "not too many ranges");
581 
582   if (trim_ranges) {
583     merge_ranges(ranges, rp);
584   }
585 
586   // Safepoint in case backward branch observed
587   if (makes_backward_branch && UseLoopSafepoints)
588     add_safepoint();
589 
590   jump_switch_ranges(lookup, &ranges[0], &ranges[rp]);
591 }
592 
if_prob(float taken_cnt,float total_cnt)593 static float if_prob(float taken_cnt, float total_cnt) {
594   assert(taken_cnt <= total_cnt, "");
595   if (total_cnt == 0) {
596     return PROB_FAIR;
597   }
598   float p = taken_cnt / total_cnt;
599   return MIN2(MAX2(p, PROB_MIN), PROB_MAX);
600 }
601 
if_cnt(float cnt)602 static float if_cnt(float cnt) {
603   if (cnt == 0) {
604     return COUNT_UNKNOWN;
605   }
606   return cnt;
607 }
608 
sum_of_cnts(SwitchRange * lo,SwitchRange * hi)609 static float sum_of_cnts(SwitchRange *lo, SwitchRange *hi) {
610   float total_cnt = 0;
611   for (SwitchRange* sr = lo; sr <= hi; sr++) {
612     total_cnt += sr->cnt();
613   }
614   return total_cnt;
615 }
616 
617 class SwitchRanges : public ResourceObj {
618 public:
619   SwitchRange* _lo;
620   SwitchRange* _hi;
621   SwitchRange* _mid;
622   float _cost;
623 
624   enum {
625     Start,
626     LeftDone,
627     RightDone,
628     Done
629   } _state;
630 
SwitchRanges(SwitchRange * lo,SwitchRange * hi)631   SwitchRanges(SwitchRange *lo, SwitchRange *hi)
632     : _lo(lo), _hi(hi), _mid(NULL),
633       _cost(0), _state(Start) {
634   }
635 
SwitchRanges()636   SwitchRanges()
637     : _lo(NULL), _hi(NULL), _mid(NULL),
638       _cost(0), _state(Start) {}
639 };
640 
641 // Estimate cost of performing a binary search on lo..hi
compute_tree_cost(SwitchRange * lo,SwitchRange * hi,float total_cnt)642 static float compute_tree_cost(SwitchRange *lo, SwitchRange *hi, float total_cnt) {
643   GrowableArray<SwitchRanges> tree;
644   SwitchRanges root(lo, hi);
645   tree.push(root);
646 
647   float cost = 0;
648   do {
649     SwitchRanges& r = *tree.adr_at(tree.length()-1);
650     if (r._hi != r._lo) {
651       if (r._mid == NULL) {
652         float r_cnt = sum_of_cnts(r._lo, r._hi);
653 
654         if (r_cnt == 0) {
655           tree.pop();
656           cost = 0;
657           continue;
658         }
659 
660         SwitchRange* mid = NULL;
661         mid = r._lo;
662         for (float cnt = 0; ; ) {
663           assert(mid <= r._hi, "out of bounds");
664           cnt += mid->cnt();
665           if (cnt > r_cnt / 2) {
666             break;
667           }
668           mid++;
669         }
670         assert(mid <= r._hi, "out of bounds");
671         r._mid = mid;
672         r._cost = r_cnt / total_cnt;
673       }
674       r._cost += cost;
675       if (r._state < SwitchRanges::LeftDone && r._mid > r._lo) {
676         cost = 0;
677         r._state = SwitchRanges::LeftDone;
678         tree.push(SwitchRanges(r._lo, r._mid-1));
679       } else if (r._state < SwitchRanges::RightDone) {
680         cost = 0;
681         r._state = SwitchRanges::RightDone;
682         tree.push(SwitchRanges(r._mid == r._lo ? r._mid+1 : r._mid, r._hi));
683       } else {
684         tree.pop();
685         cost = r._cost;
686       }
687     } else {
688       tree.pop();
689       cost = r._cost;
690     }
691   } while (tree.length() > 0);
692 
693 
694   return cost;
695 }
696 
697 // It sometimes pays off to test most common ranges before the binary search
linear_search_switch_ranges(Node * key_val,SwitchRange * & lo,SwitchRange * & hi)698 void Parse::linear_search_switch_ranges(Node* key_val, SwitchRange*& lo, SwitchRange*& hi) {
699   uint nr = hi - lo + 1;
700   float total_cnt = sum_of_cnts(lo, hi);
701 
702   float min = compute_tree_cost(lo, hi, total_cnt);
703   float extra = 1;
704   float sub = 0;
705 
706   SwitchRange* array1 = lo;
707   SwitchRange* array2 = NEW_RESOURCE_ARRAY(SwitchRange, nr);
708 
709   SwitchRange* ranges = NULL;
710 
711   while (nr >= 2) {
712     assert(lo == array1 || lo == array2, "one the 2 already allocated arrays");
713     ranges = (lo == array1) ? array2 : array1;
714 
715     // Find highest frequency range
716     SwitchRange* candidate = lo;
717     for (SwitchRange* sr = lo+1; sr <= hi; sr++) {
718       if (sr->cnt() > candidate->cnt()) {
719         candidate = sr;
720       }
721     }
722     SwitchRange most_freq = *candidate;
723     if (most_freq.cnt() == 0) {
724       break;
725     }
726 
727     // Copy remaining ranges into another array
728     int shift = 0;
729     for (uint i = 0; i < nr; i++) {
730       SwitchRange* sr = &lo[i];
731       if (sr != candidate) {
732         ranges[i-shift] = *sr;
733       } else {
734         shift++;
735         if (i > 0 && i < nr-1) {
736           SwitchRange prev = lo[i-1];
737           prev.setRange(prev.lo(), sr->hi(), prev.dest(), prev.table_index(), prev.cnt());
738           if (prev.adjoin(lo[i+1])) {
739             shift++;
740             i++;
741           }
742           ranges[i-shift] = prev;
743         }
744       }
745     }
746     nr -= shift;
747 
748     // Evaluate cost of testing the most common range and performing a
749     // binary search on the other ranges
750     float cost = extra + compute_tree_cost(&ranges[0], &ranges[nr-1], total_cnt);
751     if (cost >= min) {
752       break;
753     }
754     // swap arrays
755     lo = &ranges[0];
756     hi = &ranges[nr-1];
757 
758     // It pays off: emit the test for the most common range
759     assert(most_freq.cnt() > 0, "must be taken");
760     Node* val = _gvn.transform(new SubINode(key_val, _gvn.intcon(most_freq.lo())));
761     Node* cmp = _gvn.transform(new CmpUNode(val, _gvn.intcon(most_freq.hi() - most_freq.lo())));
762     Node* tst = _gvn.transform(new BoolNode(cmp, BoolTest::le));
763     IfNode* iff = create_and_map_if(control(), tst, if_prob(most_freq.cnt(), total_cnt), if_cnt(most_freq.cnt()));
764     jump_if_true_fork(iff, most_freq.dest(), most_freq.table_index(), false);
765 
766     sub += most_freq.cnt() / total_cnt;
767     extra += 1 - sub;
768     min = cost;
769   }
770 }
771 
772 //----------------------------create_jump_tables-------------------------------
create_jump_tables(Node * key_val,SwitchRange * lo,SwitchRange * hi)773 bool Parse::create_jump_tables(Node* key_val, SwitchRange* lo, SwitchRange* hi) {
774   // Are jumptables enabled
775   if (!UseJumpTables)  return false;
776 
777   // Are jumptables supported
778   if (!Matcher::has_match_rule(Op_Jump))  return false;
779 
780   // Don't make jump table if profiling
781   if (method_data_update())  return false;
782 
783   bool trim_ranges = !C->too_many_traps(method(), bci(), Deoptimization::Reason_unstable_if);
784 
785   // Decide if a guard is needed to lop off big ranges at either (or
786   // both) end(s) of the input set. We'll call this the default target
787   // even though we can't be sure that it is the true "default".
788 
789   bool needs_guard = false;
790   int default_dest;
791   int64_t total_outlier_size = 0;
792   int64_t hi_size = ((int64_t)hi->hi()) - ((int64_t)hi->lo()) + 1;
793   int64_t lo_size = ((int64_t)lo->hi()) - ((int64_t)lo->lo()) + 1;
794 
795   if (lo->dest() == hi->dest()) {
796     total_outlier_size = hi_size + lo_size;
797     default_dest = lo->dest();
798   } else if (lo_size > hi_size) {
799     total_outlier_size = lo_size;
800     default_dest = lo->dest();
801   } else {
802     total_outlier_size = hi_size;
803     default_dest = hi->dest();
804   }
805 
806   float total = sum_of_cnts(lo, hi);
807   float cost = compute_tree_cost(lo, hi, total);
808 
809   // If a guard test will eliminate very sparse end ranges, then
810   // it is worth the cost of an extra jump.
811   float trimmed_cnt = 0;
812   if (total_outlier_size > (MaxJumpTableSparseness * 4)) {
813     needs_guard = true;
814     if (default_dest == lo->dest()) {
815       trimmed_cnt += lo->cnt();
816       lo++;
817     }
818     if (default_dest == hi->dest()) {
819       trimmed_cnt += hi->cnt();
820       hi--;
821     }
822   }
823 
824   // Find the total number of cases and ranges
825   int64_t num_cases = ((int64_t)hi->hi()) - ((int64_t)lo->lo()) + 1;
826   int num_range = hi - lo + 1;
827 
828   // Don't create table if: too large, too small, or too sparse.
829   if (num_cases > MaxJumpTableSize)
830     return false;
831   if (UseSwitchProfiling) {
832     // MinJumpTableSize is set so with a well balanced binary tree,
833     // when the number of ranges is MinJumpTableSize, it's cheaper to
834     // go through a JumpNode that a tree of IfNodes. Average cost of a
835     // tree of IfNodes with MinJumpTableSize is
836     // log2f(MinJumpTableSize) comparisons. So if the cost computed
837     // from profile data is less than log2f(MinJumpTableSize) then
838     // going with the binary search is cheaper.
839     if (cost < log2f(MinJumpTableSize)) {
840       return false;
841     }
842   } else {
843     if (num_cases < MinJumpTableSize)
844       return false;
845   }
846   if (num_cases > (MaxJumpTableSparseness * num_range))
847     return false;
848 
849   // Normalize table lookups to zero
850   int lowval = lo->lo();
851   key_val = _gvn.transform( new SubINode(key_val, _gvn.intcon(lowval)) );
852 
853   // Generate a guard to protect against input keyvals that aren't
854   // in the switch domain.
855   if (needs_guard) {
856     Node*   size = _gvn.intcon(num_cases);
857     Node*   cmp = _gvn.transform(new CmpUNode(key_val, size));
858     Node*   tst = _gvn.transform(new BoolNode(cmp, BoolTest::ge));
859     IfNode* iff = create_and_map_if(control(), tst, if_prob(trimmed_cnt, total), if_cnt(trimmed_cnt));
860     jump_if_true_fork(iff, default_dest, NullTableIndex, trim_ranges && trimmed_cnt == 0);
861 
862     total -= trimmed_cnt;
863   }
864 
865   // Create an ideal node JumpTable that has projections
866   // of all possible ranges for a switch statement
867   // The key_val input must be converted to a pointer offset and scaled.
868   // Compare Parse::array_addressing above.
869 
870   // Clean the 32-bit int into a real 64-bit offset.
871   // Otherwise, the jint value 0 might turn into an offset of 0x0800000000.
872   const TypeInt* ikeytype = TypeInt::make(0, num_cases, Type::WidenMin);
873   // Make I2L conversion control dependent to prevent it from
874   // floating above the range check during loop optimizations.
875   key_val = C->conv_I2X_index(&_gvn, key_val, ikeytype, control());
876 
877   // Shift the value by wordsize so we have an index into the table, rather
878   // than a switch value
879   Node *shiftWord = _gvn.MakeConX(wordSize);
880   key_val = _gvn.transform( new MulXNode( key_val, shiftWord));
881 
882   // Create the JumpNode
883   Arena* arena = C->comp_arena();
884   float* probs = (float*)arena->Amalloc(sizeof(float)*num_cases);
885   int i = 0;
886   if (total == 0) {
887     for (SwitchRange* r = lo; r <= hi; r++) {
888       for (int64_t j = r->lo(); j <= r->hi(); j++, i++) {
889         probs[i] = 1.0F / num_cases;
890       }
891     }
892   } else {
893     for (SwitchRange* r = lo; r <= hi; r++) {
894       float prob = r->cnt()/total;
895       for (int64_t j = r->lo(); j <= r->hi(); j++, i++) {
896         probs[i] = prob / (r->hi() - r->lo() + 1);
897       }
898     }
899   }
900 
901   ciMethodData* methodData = method()->method_data();
902   ciMultiBranchData* profile = NULL;
903   if (methodData->is_mature()) {
904     ciProfileData* data = methodData->bci_to_data(bci());
905     if (data != NULL && data->is_MultiBranchData()) {
906       profile = (ciMultiBranchData*)data;
907     }
908   }
909 
910   Node* jtn = _gvn.transform(new JumpNode(control(), key_val, num_cases, probs, profile == NULL ? COUNT_UNKNOWN : total));
911 
912   // These are the switch destinations hanging off the jumpnode
913   i = 0;
914   for (SwitchRange* r = lo; r <= hi; r++) {
915     for (int64_t j = r->lo(); j <= r->hi(); j++, i++) {
916       Node* input = _gvn.transform(new JumpProjNode(jtn, i, r->dest(), (int)(j - lowval)));
917       {
918         PreserveJVMState pjvms(this);
919         set_control(input);
920         jump_if_always_fork(r->dest(), r->table_index(), trim_ranges && r->cnt() == 0);
921       }
922     }
923   }
924   assert(i == num_cases, "miscount of cases");
925   stop_and_kill_map();  // no more uses for this JVMS
926   return true;
927 }
928 
929 //----------------------------jump_switch_ranges-------------------------------
jump_switch_ranges(Node * key_val,SwitchRange * lo,SwitchRange * hi,int switch_depth)930 void Parse::jump_switch_ranges(Node* key_val, SwitchRange *lo, SwitchRange *hi, int switch_depth) {
931   Block* switch_block = block();
932   bool trim_ranges = !method_data_update() && !C->too_many_traps(method(), bci(), Deoptimization::Reason_unstable_if);
933 
934   if (switch_depth == 0) {
935     // Do special processing for the top-level call.
936     assert(lo->lo() == min_jint, "initial range must exhaust Type::INT");
937     assert(hi->hi() == max_jint, "initial range must exhaust Type::INT");
938 
939     // Decrement pred-numbers for the unique set of nodes.
940 #ifdef ASSERT
941     if (!trim_ranges) {
942       // Ensure that the block's successors are a (duplicate-free) set.
943       int successors_counted = 0;  // block occurrences in [hi..lo]
944       int unique_successors = switch_block->num_successors();
945       for (int i = 0; i < unique_successors; i++) {
946         Block* target = switch_block->successor_at(i);
947 
948         // Check that the set of successors is the same in both places.
949         int successors_found = 0;
950         for (SwitchRange* p = lo; p <= hi; p++) {
951           if (p->dest() == target->start())  successors_found++;
952         }
953         assert(successors_found > 0, "successor must be known");
954         successors_counted += successors_found;
955       }
956       assert(successors_counted == (hi-lo)+1, "no unexpected successors");
957     }
958 #endif
959 
960     // Maybe prune the inputs, based on the type of key_val.
961     jint min_val = min_jint;
962     jint max_val = max_jint;
963     const TypeInt* ti = key_val->bottom_type()->isa_int();
964     if (ti != NULL) {
965       min_val = ti->_lo;
966       max_val = ti->_hi;
967       assert(min_val <= max_val, "invalid int type");
968     }
969     while (lo->hi() < min_val) {
970       lo++;
971     }
972     if (lo->lo() < min_val)  {
973       lo->setRange(min_val, lo->hi(), lo->dest(), lo->table_index(), lo->cnt());
974     }
975     while (hi->lo() > max_val) {
976       hi--;
977     }
978     if (hi->hi() > max_val) {
979       hi->setRange(hi->lo(), max_val, hi->dest(), hi->table_index(), hi->cnt());
980     }
981 
982     linear_search_switch_ranges(key_val, lo, hi);
983   }
984 
985 #ifndef PRODUCT
986   if (switch_depth == 0) {
987     _max_switch_depth = 0;
988     _est_switch_depth = log2_intptr((hi-lo+1)-1)+1;
989   }
990 #endif
991 
992   assert(lo <= hi, "must be a non-empty set of ranges");
993   if (lo == hi) {
994     jump_if_always_fork(lo->dest(), lo->table_index(), trim_ranges && lo->cnt() == 0);
995   } else {
996     assert(lo->hi() == (lo+1)->lo()-1, "contiguous ranges");
997     assert(hi->lo() == (hi-1)->hi()+1, "contiguous ranges");
998 
999     if (create_jump_tables(key_val, lo, hi)) return;
1000 
1001     SwitchRange* mid = NULL;
1002     float total_cnt = sum_of_cnts(lo, hi);
1003 
1004     int nr = hi - lo + 1;
1005     if (UseSwitchProfiling) {
1006       // Don't keep the binary search tree balanced: pick up mid point
1007       // that split frequencies in half.
1008       float cnt = 0;
1009       for (SwitchRange* sr = lo; sr <= hi; sr++) {
1010         cnt += sr->cnt();
1011         if (cnt >= total_cnt / 2) {
1012           mid = sr;
1013           break;
1014         }
1015       }
1016     } else {
1017       mid = lo + nr/2;
1018 
1019       // if there is an easy choice, pivot at a singleton:
1020       if (nr > 3 && !mid->is_singleton() && (mid-1)->is_singleton())  mid--;
1021 
1022       assert(lo < mid && mid <= hi, "good pivot choice");
1023       assert(nr != 2 || mid == hi,   "should pick higher of 2");
1024       assert(nr != 3 || mid == hi-1, "should pick middle of 3");
1025     }
1026 
1027 
1028     Node *test_val = _gvn.intcon(mid == lo ? mid->hi() : mid->lo());
1029 
1030     if (mid->is_singleton()) {
1031       IfNode *iff_ne = jump_if_fork_int(key_val, test_val, BoolTest::ne, 1-if_prob(mid->cnt(), total_cnt), if_cnt(mid->cnt()));
1032       jump_if_false_fork(iff_ne, mid->dest(), mid->table_index(), trim_ranges && mid->cnt() == 0);
1033 
1034       // Special Case:  If there are exactly three ranges, and the high
1035       // and low range each go to the same place, omit the "gt" test,
1036       // since it will not discriminate anything.
1037       bool eq_test_only = (hi == lo+2 && hi->dest() == lo->dest() && mid == hi-1) || mid == lo;
1038 
1039       // if there is a higher range, test for it and process it:
1040       if (mid < hi && !eq_test_only) {
1041         // two comparisons of same values--should enable 1 test for 2 branches
1042         // Use BoolTest::lt instead of BoolTest::gt
1043         float cnt = sum_of_cnts(lo, mid-1);
1044         IfNode *iff_lt  = jump_if_fork_int(key_val, test_val, BoolTest::lt, if_prob(cnt, total_cnt), if_cnt(cnt));
1045         Node   *iftrue  = _gvn.transform( new IfTrueNode(iff_lt) );
1046         Node   *iffalse = _gvn.transform( new IfFalseNode(iff_lt) );
1047         { PreserveJVMState pjvms(this);
1048           set_control(iffalse);
1049           jump_switch_ranges(key_val, mid+1, hi, switch_depth+1);
1050         }
1051         set_control(iftrue);
1052       }
1053 
1054     } else {
1055       // mid is a range, not a singleton, so treat mid..hi as a unit
1056       float cnt = sum_of_cnts(mid == lo ? mid+1 : mid, hi);
1057       IfNode *iff_ge = jump_if_fork_int(key_val, test_val, mid == lo ? BoolTest::gt : BoolTest::ge, if_prob(cnt, total_cnt), if_cnt(cnt));
1058 
1059       // if there is a higher range, test for it and process it:
1060       if (mid == hi) {
1061         jump_if_true_fork(iff_ge, mid->dest(), mid->table_index(), trim_ranges && cnt == 0);
1062       } else {
1063         Node *iftrue  = _gvn.transform( new IfTrueNode(iff_ge) );
1064         Node *iffalse = _gvn.transform( new IfFalseNode(iff_ge) );
1065         { PreserveJVMState pjvms(this);
1066           set_control(iftrue);
1067           jump_switch_ranges(key_val, mid == lo ? mid+1 : mid, hi, switch_depth+1);
1068         }
1069         set_control(iffalse);
1070       }
1071     }
1072 
1073     // in any case, process the lower range
1074     if (mid == lo) {
1075       if (mid->is_singleton()) {
1076         jump_switch_ranges(key_val, lo+1, hi, switch_depth+1);
1077       } else {
1078         jump_if_always_fork(lo->dest(), lo->table_index(), trim_ranges && lo->cnt() == 0);
1079       }
1080     } else {
1081       jump_switch_ranges(key_val, lo, mid-1, switch_depth+1);
1082     }
1083   }
1084 
1085   // Decrease pred_count for each successor after all is done.
1086   if (switch_depth == 0) {
1087     int unique_successors = switch_block->num_successors();
1088     for (int i = 0; i < unique_successors; i++) {
1089       Block* target = switch_block->successor_at(i);
1090       // Throw away the pre-allocated path for each unique successor.
1091       target->next_path_num();
1092     }
1093   }
1094 
1095 #ifndef PRODUCT
1096   _max_switch_depth = MAX2(switch_depth, _max_switch_depth);
1097   if (TraceOptoParse && Verbose && WizardMode && switch_depth == 0) {
1098     SwitchRange* r;
1099     int nsing = 0;
1100     for( r = lo; r <= hi; r++ ) {
1101       if( r->is_singleton() )  nsing++;
1102     }
1103     tty->print(">>> ");
1104     _method->print_short_name();
1105     tty->print_cr(" switch decision tree");
1106     tty->print_cr("    %d ranges (%d singletons), max_depth=%d, est_depth=%d",
1107                   (int) (hi-lo+1), nsing, _max_switch_depth, _est_switch_depth);
1108     if (_max_switch_depth > _est_switch_depth) {
1109       tty->print_cr("******** BAD SWITCH DEPTH ********");
1110     }
1111     tty->print("   ");
1112     for( r = lo; r <= hi; r++ ) {
1113       r->print();
1114     }
1115     tty->cr();
1116   }
1117 #endif
1118 }
1119 
modf()1120 void Parse::modf() {
1121   Node *f2 = pop();
1122   Node *f1 = pop();
1123   Node* c = make_runtime_call(RC_LEAF, OptoRuntime::modf_Type(),
1124                               CAST_FROM_FN_PTR(address, SharedRuntime::frem),
1125                               "frem", NULL, //no memory effects
1126                               f1, f2);
1127   Node* res = _gvn.transform(new ProjNode(c, TypeFunc::Parms + 0));
1128 
1129   push(res);
1130 }
1131 
modd()1132 void Parse::modd() {
1133   Node *d2 = pop_pair();
1134   Node *d1 = pop_pair();
1135   Node* c = make_runtime_call(RC_LEAF, OptoRuntime::Math_DD_D_Type(),
1136                               CAST_FROM_FN_PTR(address, SharedRuntime::drem),
1137                               "drem", NULL, //no memory effects
1138                               d1, top(), d2, top());
1139   Node* res_d   = _gvn.transform(new ProjNode(c, TypeFunc::Parms + 0));
1140 
1141 #ifdef ASSERT
1142   Node* res_top = _gvn.transform(new ProjNode(c, TypeFunc::Parms + 1));
1143   assert(res_top == top(), "second value must be top");
1144 #endif
1145 
1146   push_pair(res_d);
1147 }
1148 
l2f()1149 void Parse::l2f() {
1150   Node* f2 = pop();
1151   Node* f1 = pop();
1152   Node* c = make_runtime_call(RC_LEAF, OptoRuntime::l2f_Type(),
1153                               CAST_FROM_FN_PTR(address, SharedRuntime::l2f),
1154                               "l2f", NULL, //no memory effects
1155                               f1, f2);
1156   Node* res = _gvn.transform(new ProjNode(c, TypeFunc::Parms + 0));
1157 
1158   push(res);
1159 }
1160 
do_irem()1161 void Parse::do_irem() {
1162   // Must keep both values on the expression-stack during null-check
1163   zero_check_int(peek());
1164   // Compile-time detect of null-exception?
1165   if (stopped())  return;
1166 
1167   Node* b = pop();
1168   Node* a = pop();
1169 
1170   const Type *t = _gvn.type(b);
1171   if (t != Type::TOP) {
1172     const TypeInt *ti = t->is_int();
1173     if (ti->is_con()) {
1174       int divisor = ti->get_con();
1175       // check for positive power of 2
1176       if (divisor > 0 &&
1177           (divisor & ~(divisor-1)) == divisor) {
1178         // yes !
1179         Node *mask = _gvn.intcon((divisor - 1));
1180         // Sigh, must handle negative dividends
1181         Node *zero = _gvn.intcon(0);
1182         IfNode *ifff = jump_if_fork_int(a, zero, BoolTest::lt, PROB_FAIR, COUNT_UNKNOWN);
1183         Node *iff = _gvn.transform( new IfFalseNode(ifff) );
1184         Node *ift = _gvn.transform( new IfTrueNode (ifff) );
1185         Node *reg = jump_if_join(ift, iff);
1186         Node *phi = PhiNode::make(reg, NULL, TypeInt::INT);
1187         // Negative path; negate/and/negate
1188         Node *neg = _gvn.transform( new SubINode(zero, a) );
1189         Node *andn= _gvn.transform( new AndINode(neg, mask) );
1190         Node *negn= _gvn.transform( new SubINode(zero, andn) );
1191         phi->init_req(1, negn);
1192         // Fast positive case
1193         Node *andx = _gvn.transform( new AndINode(a, mask) );
1194         phi->init_req(2, andx);
1195         // Push the merge
1196         push( _gvn.transform(phi) );
1197         return;
1198       }
1199     }
1200   }
1201   // Default case
1202   push( _gvn.transform( new ModINode(control(),a,b) ) );
1203 }
1204 
1205 // Handle jsr and jsr_w bytecode
do_jsr()1206 void Parse::do_jsr() {
1207   assert(bc() == Bytecodes::_jsr || bc() == Bytecodes::_jsr_w, "wrong bytecode");
1208 
1209   // Store information about current state, tagged with new _jsr_bci
1210   int return_bci = iter().next_bci();
1211   int jsr_bci    = (bc() == Bytecodes::_jsr) ? iter().get_dest() : iter().get_far_dest();
1212 
1213   // Update method data
1214   profile_taken_branch(jsr_bci);
1215 
1216   // The way we do things now, there is only one successor block
1217   // for the jsr, because the target code is cloned by ciTypeFlow.
1218   Block* target = successor_for_bci(jsr_bci);
1219 
1220   // What got pushed?
1221   const Type* ret_addr = target->peek();
1222   assert(ret_addr->singleton(), "must be a constant (cloned jsr body)");
1223 
1224   // Effect on jsr on stack
1225   push(_gvn.makecon(ret_addr));
1226 
1227   // Flow to the jsr.
1228   merge(jsr_bci);
1229 }
1230 
1231 // Handle ret bytecode
do_ret()1232 void Parse::do_ret() {
1233   // Find to whom we return.
1234   assert(block()->num_successors() == 1, "a ret can only go one place now");
1235   Block* target = block()->successor_at(0);
1236   assert(!target->is_ready(), "our arrival must be expected");
1237   profile_ret(target->flow()->start());
1238   int pnum = target->next_path_num();
1239   merge_common(target, pnum);
1240 }
1241 
has_injected_profile(BoolTest::mask btest,Node * test,int & taken,int & not_taken)1242 static bool has_injected_profile(BoolTest::mask btest, Node* test, int& taken, int& not_taken) {
1243   if (btest != BoolTest::eq && btest != BoolTest::ne) {
1244     // Only ::eq and ::ne are supported for profile injection.
1245     return false;
1246   }
1247   if (test->is_Cmp() &&
1248       test->in(1)->Opcode() == Op_ProfileBoolean) {
1249     ProfileBooleanNode* profile = (ProfileBooleanNode*)test->in(1);
1250     int false_cnt = profile->false_count();
1251     int  true_cnt = profile->true_count();
1252 
1253     // Counts matching depends on the actual test operation (::eq or ::ne).
1254     // No need to scale the counts because profile injection was designed
1255     // to feed exact counts into VM.
1256     taken     = (btest == BoolTest::eq) ? false_cnt :  true_cnt;
1257     not_taken = (btest == BoolTest::eq) ?  true_cnt : false_cnt;
1258 
1259     profile->consume();
1260     return true;
1261   }
1262   return false;
1263 }
1264 //--------------------------dynamic_branch_prediction--------------------------
1265 // Try to gather dynamic branch prediction behavior.  Return a probability
1266 // of the branch being taken and set the "cnt" field.  Returns a -1.0
1267 // if we need to use static prediction for some reason.
dynamic_branch_prediction(float & cnt,BoolTest::mask btest,Node * test)1268 float Parse::dynamic_branch_prediction(float &cnt, BoolTest::mask btest, Node* test) {
1269   ResourceMark rm;
1270 
1271   cnt  = COUNT_UNKNOWN;
1272 
1273   int     taken = 0;
1274   int not_taken = 0;
1275 
1276   bool use_mdo = !has_injected_profile(btest, test, taken, not_taken);
1277 
1278   if (use_mdo) {
1279     // Use MethodData information if it is available
1280     // FIXME: free the ProfileData structure
1281     ciMethodData* methodData = method()->method_data();
1282     if (!methodData->is_mature())  return PROB_UNKNOWN;
1283     ciProfileData* data = methodData->bci_to_data(bci());
1284     if (data == NULL) {
1285       return PROB_UNKNOWN;
1286     }
1287     if (!data->is_JumpData())  return PROB_UNKNOWN;
1288 
1289     // get taken and not taken values
1290     taken = data->as_JumpData()->taken();
1291     not_taken = 0;
1292     if (data->is_BranchData()) {
1293       not_taken = data->as_BranchData()->not_taken();
1294     }
1295 
1296     // scale the counts to be commensurate with invocation counts:
1297     taken = method()->scale_count(taken);
1298     not_taken = method()->scale_count(not_taken);
1299   }
1300 
1301   // Give up if too few (or too many, in which case the sum will overflow) counts to be meaningful.
1302   // We also check that individual counters are positive first, otherwise the sum can become positive.
1303   if (taken < 0 || not_taken < 0 || taken + not_taken < 40) {
1304     if (C->log() != NULL) {
1305       C->log()->elem("branch target_bci='%d' taken='%d' not_taken='%d'", iter().get_dest(), taken, not_taken);
1306     }
1307     return PROB_UNKNOWN;
1308   }
1309 
1310   // Compute frequency that we arrive here
1311   float sum = taken + not_taken;
1312   // Adjust, if this block is a cloned private block but the
1313   // Jump counts are shared.  Taken the private counts for
1314   // just this path instead of the shared counts.
1315   if( block()->count() > 0 )
1316     sum = block()->count();
1317   cnt = sum / FreqCountInvocations;
1318 
1319   // Pin probability to sane limits
1320   float prob;
1321   if( !taken )
1322     prob = (0+PROB_MIN) / 2;
1323   else if( !not_taken )
1324     prob = (1+PROB_MAX) / 2;
1325   else {                         // Compute probability of true path
1326     prob = (float)taken / (float)(taken + not_taken);
1327     if (prob > PROB_MAX)  prob = PROB_MAX;
1328     if (prob < PROB_MIN)   prob = PROB_MIN;
1329   }
1330 
1331   assert((cnt > 0.0f) && (prob > 0.0f),
1332          "Bad frequency assignment in if");
1333 
1334   if (C->log() != NULL) {
1335     const char* prob_str = NULL;
1336     if (prob >= PROB_MAX)  prob_str = (prob == PROB_MAX) ? "max" : "always";
1337     if (prob <= PROB_MIN)  prob_str = (prob == PROB_MIN) ? "min" : "never";
1338     char prob_str_buf[30];
1339     if (prob_str == NULL) {
1340       jio_snprintf(prob_str_buf, sizeof(prob_str_buf), "%20.2f", prob);
1341       prob_str = prob_str_buf;
1342     }
1343     C->log()->elem("branch target_bci='%d' taken='%d' not_taken='%d' cnt='%f' prob='%s'",
1344                    iter().get_dest(), taken, not_taken, cnt, prob_str);
1345   }
1346   return prob;
1347 }
1348 
1349 //-----------------------------branch_prediction-------------------------------
branch_prediction(float & cnt,BoolTest::mask btest,int target_bci,Node * test)1350 float Parse::branch_prediction(float& cnt,
1351                                BoolTest::mask btest,
1352                                int target_bci,
1353                                Node* test) {
1354   float prob = dynamic_branch_prediction(cnt, btest, test);
1355   // If prob is unknown, switch to static prediction
1356   if (prob != PROB_UNKNOWN)  return prob;
1357 
1358   prob = PROB_FAIR;                   // Set default value
1359   if (btest == BoolTest::eq)          // Exactly equal test?
1360     prob = PROB_STATIC_INFREQUENT;    // Assume its relatively infrequent
1361   else if (btest == BoolTest::ne)
1362     prob = PROB_STATIC_FREQUENT;      // Assume its relatively frequent
1363 
1364   // If this is a conditional test guarding a backwards branch,
1365   // assume its a loop-back edge.  Make it a likely taken branch.
1366   if (target_bci < bci()) {
1367     if (is_osr_parse()) {    // Could be a hot OSR'd loop; force deopt
1368       // Since it's an OSR, we probably have profile data, but since
1369       // branch_prediction returned PROB_UNKNOWN, the counts are too small.
1370       // Let's make a special check here for completely zero counts.
1371       ciMethodData* methodData = method()->method_data();
1372       if (!methodData->is_empty()) {
1373         ciProfileData* data = methodData->bci_to_data(bci());
1374         // Only stop for truly zero counts, which mean an unknown part
1375         // of the OSR-ed method, and we want to deopt to gather more stats.
1376         // If you have ANY counts, then this loop is simply 'cold' relative
1377         // to the OSR loop.
1378         if (data == NULL ||
1379             (data->as_BranchData()->taken() +  data->as_BranchData()->not_taken() == 0)) {
1380           // This is the only way to return PROB_UNKNOWN:
1381           return PROB_UNKNOWN;
1382         }
1383       }
1384     }
1385     prob = PROB_STATIC_FREQUENT;     // Likely to take backwards branch
1386   }
1387 
1388   assert(prob != PROB_UNKNOWN, "must have some guess at this point");
1389   return prob;
1390 }
1391 
1392 // The magic constants are chosen so as to match the output of
1393 // branch_prediction() when the profile reports a zero taken count.
1394 // It is important to distinguish zero counts unambiguously, because
1395 // some branches (e.g., _213_javac.Assembler.eliminate) validly produce
1396 // very small but nonzero probabilities, which if confused with zero
1397 // counts would keep the program recompiling indefinitely.
seems_never_taken(float prob) const1398 bool Parse::seems_never_taken(float prob) const {
1399   return prob < PROB_MIN;
1400 }
1401 
1402 // True if the comparison seems to be the kind that will not change its
1403 // statistics from true to false.  See comments in adjust_map_after_if.
1404 // This question is only asked along paths which are already
1405 // classifed as untaken (by seems_never_taken), so really,
1406 // if a path is never taken, its controlling comparison is
1407 // already acting in a stable fashion.  If the comparison
1408 // seems stable, we will put an expensive uncommon trap
1409 // on the untaken path.
seems_stable_comparison() const1410 bool Parse::seems_stable_comparison() const {
1411   if (C->too_many_traps(method(), bci(), Deoptimization::Reason_unstable_if)) {
1412     return false;
1413   }
1414   return true;
1415 }
1416 
1417 //-------------------------------repush_if_args--------------------------------
1418 // Push arguments of an "if" bytecode back onto the stack by adjusting _sp.
repush_if_args()1419 inline int Parse::repush_if_args() {
1420   if (PrintOpto && WizardMode) {
1421     tty->print("defending against excessive implicit null exceptions on %s @%d in ",
1422                Bytecodes::name(iter().cur_bc()), iter().cur_bci());
1423     method()->print_name(); tty->cr();
1424   }
1425   int bc_depth = - Bytecodes::depth(iter().cur_bc());
1426   assert(bc_depth == 1 || bc_depth == 2, "only two kinds of branches");
1427   DEBUG_ONLY(sync_jvms());   // argument(n) requires a synced jvms
1428   assert(argument(0) != NULL, "must exist");
1429   assert(bc_depth == 1 || argument(1) != NULL, "two must exist");
1430   inc_sp(bc_depth);
1431   return bc_depth;
1432 }
1433 
1434 //----------------------------------do_ifnull----------------------------------
do_ifnull(BoolTest::mask btest,Node * c)1435 void Parse::do_ifnull(BoolTest::mask btest, Node *c) {
1436   int target_bci = iter().get_dest();
1437 
1438   Block* branch_block = successor_for_bci(target_bci);
1439   Block* next_block   = successor_for_bci(iter().next_bci());
1440 
1441   float cnt;
1442   float prob = branch_prediction(cnt, btest, target_bci, c);
1443   if (prob == PROB_UNKNOWN) {
1444     // (An earlier version of do_ifnull omitted this trap for OSR methods.)
1445     if (PrintOpto && Verbose) {
1446       tty->print_cr("Never-taken edge stops compilation at bci %d", bci());
1447     }
1448     repush_if_args(); // to gather stats on loop
1449     // We need to mark this branch as taken so that if we recompile we will
1450     // see that it is possible. In the tiered system the interpreter doesn't
1451     // do profiling and by the time we get to the lower tier from the interpreter
1452     // the path may be cold again. Make sure it doesn't look untaken
1453     profile_taken_branch(target_bci, !ProfileInterpreter);
1454     uncommon_trap(Deoptimization::Reason_unreached,
1455                   Deoptimization::Action_reinterpret,
1456                   NULL, "cold");
1457     if (C->eliminate_boxing()) {
1458       // Mark the successor blocks as parsed
1459       branch_block->next_path_num();
1460       next_block->next_path_num();
1461     }
1462     return;
1463   }
1464 
1465   NOT_PRODUCT(explicit_null_checks_inserted++);
1466 
1467   // Generate real control flow
1468   Node   *tst = _gvn.transform( new BoolNode( c, btest ) );
1469 
1470   // Sanity check the probability value
1471   assert(prob > 0.0f,"Bad probability in Parser");
1472  // Need xform to put node in hash table
1473   IfNode *iff = create_and_xform_if( control(), tst, prob, cnt );
1474   assert(iff->_prob > 0.0f,"Optimizer made bad probability in parser");
1475   // True branch
1476   { PreserveJVMState pjvms(this);
1477     Node* iftrue  = _gvn.transform( new IfTrueNode (iff) );
1478     set_control(iftrue);
1479 
1480     if (stopped()) {            // Path is dead?
1481       NOT_PRODUCT(explicit_null_checks_elided++);
1482       if (C->eliminate_boxing()) {
1483         // Mark the successor block as parsed
1484         branch_block->next_path_num();
1485       }
1486     } else {                    // Path is live.
1487       // Update method data
1488       profile_taken_branch(target_bci);
1489       adjust_map_after_if(btest, c, prob, branch_block, next_block);
1490       if (!stopped()) {
1491         merge(target_bci);
1492       }
1493     }
1494   }
1495 
1496   // False branch
1497   Node* iffalse = _gvn.transform( new IfFalseNode(iff) );
1498   set_control(iffalse);
1499 
1500   if (stopped()) {              // Path is dead?
1501     NOT_PRODUCT(explicit_null_checks_elided++);
1502     if (C->eliminate_boxing()) {
1503       // Mark the successor block as parsed
1504       next_block->next_path_num();
1505     }
1506   } else  {                     // Path is live.
1507     // Update method data
1508     profile_not_taken_branch();
1509     adjust_map_after_if(BoolTest(btest).negate(), c, 1.0-prob,
1510                         next_block, branch_block);
1511   }
1512 }
1513 
1514 //------------------------------------do_if------------------------------------
do_if(BoolTest::mask btest,Node * c)1515 void Parse::do_if(BoolTest::mask btest, Node* c) {
1516   int target_bci = iter().get_dest();
1517 
1518   Block* branch_block = successor_for_bci(target_bci);
1519   Block* next_block   = successor_for_bci(iter().next_bci());
1520 
1521   float cnt;
1522   float prob = branch_prediction(cnt, btest, target_bci, c);
1523   float untaken_prob = 1.0 - prob;
1524 
1525   if (prob == PROB_UNKNOWN) {
1526     if (PrintOpto && Verbose) {
1527       tty->print_cr("Never-taken edge stops compilation at bci %d", bci());
1528     }
1529     repush_if_args(); // to gather stats on loop
1530     // We need to mark this branch as taken so that if we recompile we will
1531     // see that it is possible. In the tiered system the interpreter doesn't
1532     // do profiling and by the time we get to the lower tier from the interpreter
1533     // the path may be cold again. Make sure it doesn't look untaken
1534     profile_taken_branch(target_bci, !ProfileInterpreter);
1535     uncommon_trap(Deoptimization::Reason_unreached,
1536                   Deoptimization::Action_reinterpret,
1537                   NULL, "cold");
1538     if (C->eliminate_boxing()) {
1539       // Mark the successor blocks as parsed
1540       branch_block->next_path_num();
1541       next_block->next_path_num();
1542     }
1543     return;
1544   }
1545 
1546   // Sanity check the probability value
1547   assert(0.0f < prob && prob < 1.0f,"Bad probability in Parser");
1548 
1549   bool taken_if_true = true;
1550   // Convert BoolTest to canonical form:
1551   if (!BoolTest(btest).is_canonical()) {
1552     btest         = BoolTest(btest).negate();
1553     taken_if_true = false;
1554     // prob is NOT updated here; it remains the probability of the taken
1555     // path (as opposed to the prob of the path guarded by an 'IfTrueNode').
1556   }
1557   assert(btest != BoolTest::eq, "!= is the only canonical exact test");
1558 
1559   Node* tst0 = new BoolNode(c, btest);
1560   Node* tst = _gvn.transform(tst0);
1561   BoolTest::mask taken_btest   = BoolTest::illegal;
1562   BoolTest::mask untaken_btest = BoolTest::illegal;
1563 
1564   if (tst->is_Bool()) {
1565     // Refresh c from the transformed bool node, since it may be
1566     // simpler than the original c.  Also re-canonicalize btest.
1567     // This wins when (Bool ne (Conv2B p) 0) => (Bool ne (CmpP p NULL)).
1568     // That can arise from statements like: if (x instanceof C) ...
1569     if (tst != tst0) {
1570       // Canonicalize one more time since transform can change it.
1571       btest = tst->as_Bool()->_test._test;
1572       if (!BoolTest(btest).is_canonical()) {
1573         // Reverse edges one more time...
1574         tst   = _gvn.transform( tst->as_Bool()->negate(&_gvn) );
1575         btest = tst->as_Bool()->_test._test;
1576         assert(BoolTest(btest).is_canonical(), "sanity");
1577         taken_if_true = !taken_if_true;
1578       }
1579       c = tst->in(1);
1580     }
1581     BoolTest::mask neg_btest = BoolTest(btest).negate();
1582     taken_btest   = taken_if_true ?     btest : neg_btest;
1583     untaken_btest = taken_if_true ? neg_btest :     btest;
1584   }
1585 
1586   // Generate real control flow
1587   float true_prob = (taken_if_true ? prob : untaken_prob);
1588   IfNode* iff = create_and_map_if(control(), tst, true_prob, cnt);
1589   assert(iff->_prob > 0.0f,"Optimizer made bad probability in parser");
1590   Node* taken_branch   = new IfTrueNode(iff);
1591   Node* untaken_branch = new IfFalseNode(iff);
1592   if (!taken_if_true) {  // Finish conversion to canonical form
1593     Node* tmp      = taken_branch;
1594     taken_branch   = untaken_branch;
1595     untaken_branch = tmp;
1596   }
1597 
1598   // Branch is taken:
1599   { PreserveJVMState pjvms(this);
1600     taken_branch = _gvn.transform(taken_branch);
1601     set_control(taken_branch);
1602 
1603     if (stopped()) {
1604       if (C->eliminate_boxing()) {
1605         // Mark the successor block as parsed
1606         branch_block->next_path_num();
1607       }
1608     } else {
1609       // Update method data
1610       profile_taken_branch(target_bci);
1611       adjust_map_after_if(taken_btest, c, prob, branch_block, next_block);
1612       if (!stopped()) {
1613         merge(target_bci);
1614       }
1615     }
1616   }
1617 
1618   untaken_branch = _gvn.transform(untaken_branch);
1619   set_control(untaken_branch);
1620 
1621   // Branch not taken.
1622   if (stopped()) {
1623     if (C->eliminate_boxing()) {
1624       // Mark the successor block as parsed
1625       next_block->next_path_num();
1626     }
1627   } else {
1628     // Update method data
1629     profile_not_taken_branch();
1630     adjust_map_after_if(untaken_btest, c, untaken_prob,
1631                         next_block, branch_block);
1632   }
1633 }
1634 
path_is_suitable_for_uncommon_trap(float prob) const1635 bool Parse::path_is_suitable_for_uncommon_trap(float prob) const {
1636   // Don't want to speculate on uncommon traps when running with -Xcomp
1637   if (!UseInterpreter) {
1638     return false;
1639   }
1640   return (seems_never_taken(prob) && seems_stable_comparison());
1641 }
1642 
maybe_add_predicate_after_if(Block * path)1643 void Parse::maybe_add_predicate_after_if(Block* path) {
1644   if (path->is_SEL_head() && path->preds_parsed() == 0) {
1645     // Add predicates at bci of if dominating the loop so traps can be
1646     // recorded on the if's profile data
1647     int bc_depth = repush_if_args();
1648     add_predicate();
1649     dec_sp(bc_depth);
1650     path->set_has_predicates();
1651   }
1652 }
1653 
1654 
1655 //----------------------------adjust_map_after_if------------------------------
1656 // Adjust the JVM state to reflect the result of taking this path.
1657 // Basically, it means inspecting the CmpNode controlling this
1658 // branch, seeing how it constrains a tested value, and then
1659 // deciding if it's worth our while to encode this constraint
1660 // as graph nodes in the current abstract interpretation map.
adjust_map_after_if(BoolTest::mask btest,Node * c,float prob,Block * path,Block * other_path)1661 void Parse::adjust_map_after_if(BoolTest::mask btest, Node* c, float prob,
1662                                 Block* path, Block* other_path) {
1663   if (!c->is_Cmp()) {
1664     maybe_add_predicate_after_if(path);
1665     return;
1666   }
1667 
1668   if (stopped() || btest == BoolTest::illegal) {
1669     return;                             // nothing to do
1670   }
1671 
1672   bool is_fallthrough = (path == successor_for_bci(iter().next_bci()));
1673 
1674   if (path_is_suitable_for_uncommon_trap(prob)) {
1675     repush_if_args();
1676     uncommon_trap(Deoptimization::Reason_unstable_if,
1677                   Deoptimization::Action_reinterpret,
1678                   NULL,
1679                   (is_fallthrough ? "taken always" : "taken never"));
1680     return;
1681   }
1682 
1683   Node* val = c->in(1);
1684   Node* con = c->in(2);
1685   const Type* tcon = _gvn.type(con);
1686   const Type* tval = _gvn.type(val);
1687   bool have_con = tcon->singleton();
1688   if (tval->singleton()) {
1689     if (!have_con) {
1690       // Swap, so constant is in con.
1691       con  = val;
1692       tcon = tval;
1693       val  = c->in(2);
1694       tval = _gvn.type(val);
1695       btest = BoolTest(btest).commute();
1696       have_con = true;
1697     } else {
1698       // Do we have two constants?  Then leave well enough alone.
1699       have_con = false;
1700     }
1701   }
1702   if (!have_con) {                        // remaining adjustments need a con
1703     maybe_add_predicate_after_if(path);
1704     return;
1705   }
1706 
1707   sharpen_type_after_if(btest, con, tcon, val, tval);
1708   maybe_add_predicate_after_if(path);
1709 }
1710 
1711 
extract_obj_from_klass_load(PhaseGVN * gvn,Node * n)1712 static Node* extract_obj_from_klass_load(PhaseGVN* gvn, Node* n) {
1713   Node* ldk;
1714   if (n->is_DecodeNKlass()) {
1715     if (n->in(1)->Opcode() != Op_LoadNKlass) {
1716       return NULL;
1717     } else {
1718       ldk = n->in(1);
1719     }
1720   } else if (n->Opcode() != Op_LoadKlass) {
1721     return NULL;
1722   } else {
1723     ldk = n;
1724   }
1725   assert(ldk != NULL && ldk->is_Load(), "should have found a LoadKlass or LoadNKlass node");
1726 
1727   Node* adr = ldk->in(MemNode::Address);
1728   intptr_t off = 0;
1729   Node* obj = AddPNode::Ideal_base_and_offset(adr, gvn, off);
1730   if (obj == NULL || off != oopDesc::klass_offset_in_bytes()) // loading oopDesc::_klass?
1731     return NULL;
1732   const TypePtr* tp = gvn->type(obj)->is_ptr();
1733   if (tp == NULL || !(tp->isa_instptr() || tp->isa_aryptr())) // is obj a Java object ptr?
1734     return NULL;
1735 
1736   return obj;
1737 }
1738 
sharpen_type_after_if(BoolTest::mask btest,Node * con,const Type * tcon,Node * val,const Type * tval)1739 void Parse::sharpen_type_after_if(BoolTest::mask btest,
1740                                   Node* con, const Type* tcon,
1741                                   Node* val, const Type* tval) {
1742   // Look for opportunities to sharpen the type of a node
1743   // whose klass is compared with a constant klass.
1744   if (btest == BoolTest::eq && tcon->isa_klassptr()) {
1745     Node* obj = extract_obj_from_klass_load(&_gvn, val);
1746     const TypeOopPtr* con_type = tcon->isa_klassptr()->as_instance_type();
1747     if (obj != NULL && (con_type->isa_instptr() || con_type->isa_aryptr())) {
1748        // Found:
1749        //   Bool(CmpP(LoadKlass(obj._klass), ConP(Foo.klass)), [eq])
1750        // or the narrowOop equivalent.
1751        const Type* obj_type = _gvn.type(obj);
1752        const TypeOopPtr* tboth = obj_type->join_speculative(con_type)->isa_oopptr();
1753        if (tboth != NULL && tboth->klass_is_exact() && tboth != obj_type &&
1754            tboth->higher_equal(obj_type)) {
1755           // obj has to be of the exact type Foo if the CmpP succeeds.
1756           int obj_in_map = map()->find_edge(obj);
1757           JVMState* jvms = this->jvms();
1758           if (obj_in_map >= 0 &&
1759               (jvms->is_loc(obj_in_map) || jvms->is_stk(obj_in_map))) {
1760             TypeNode* ccast = new CheckCastPPNode(control(), obj, tboth);
1761             const Type* tcc = ccast->as_Type()->type();
1762             assert(tcc != obj_type && tcc->higher_equal(obj_type), "must improve");
1763             // Delay transform() call to allow recovery of pre-cast value
1764             // at the control merge.
1765             _gvn.set_type_bottom(ccast);
1766             record_for_igvn(ccast);
1767             // Here's the payoff.
1768             replace_in_map(obj, ccast);
1769           }
1770        }
1771     }
1772   }
1773 
1774   int val_in_map = map()->find_edge(val);
1775   if (val_in_map < 0)  return;          // replace_in_map would be useless
1776   {
1777     JVMState* jvms = this->jvms();
1778     if (!(jvms->is_loc(val_in_map) ||
1779           jvms->is_stk(val_in_map)))
1780       return;                           // again, it would be useless
1781   }
1782 
1783   // Check for a comparison to a constant, and "know" that the compared
1784   // value is constrained on this path.
1785   assert(tcon->singleton(), "");
1786   ConstraintCastNode* ccast = NULL;
1787   Node* cast = NULL;
1788 
1789   switch (btest) {
1790   case BoolTest::eq:                    // Constant test?
1791     {
1792       const Type* tboth = tcon->join_speculative(tval);
1793       if (tboth == tval)  break;        // Nothing to gain.
1794       if (tcon->isa_int()) {
1795         ccast = new CastIINode(val, tboth);
1796       } else if (tcon == TypePtr::NULL_PTR) {
1797         // Cast to null, but keep the pointer identity temporarily live.
1798         ccast = new CastPPNode(val, tboth);
1799       } else {
1800         const TypeF* tf = tcon->isa_float_constant();
1801         const TypeD* td = tcon->isa_double_constant();
1802         // Exclude tests vs float/double 0 as these could be
1803         // either +0 or -0.  Just because you are equal to +0
1804         // doesn't mean you ARE +0!
1805         // Note, following code also replaces Long and Oop values.
1806         if ((!tf || tf->_f != 0.0) &&
1807             (!td || td->_d != 0.0))
1808           cast = con;                   // Replace non-constant val by con.
1809       }
1810     }
1811     break;
1812 
1813   case BoolTest::ne:
1814     if (tcon == TypePtr::NULL_PTR) {
1815       cast = cast_not_null(val, false);
1816     }
1817     break;
1818 
1819   default:
1820     // (At this point we could record int range types with CastII.)
1821     break;
1822   }
1823 
1824   if (ccast != NULL) {
1825     const Type* tcc = ccast->as_Type()->type();
1826     assert(tcc != tval && tcc->higher_equal(tval), "must improve");
1827     // Delay transform() call to allow recovery of pre-cast value
1828     // at the control merge.
1829     ccast->set_req(0, control());
1830     _gvn.set_type_bottom(ccast);
1831     record_for_igvn(ccast);
1832     cast = ccast;
1833   }
1834 
1835   if (cast != NULL) {                   // Here's the payoff.
1836     replace_in_map(val, cast);
1837   }
1838 }
1839 
1840 /**
1841  * Use speculative type to optimize CmpP node: if comparison is
1842  * against the low level class, cast the object to the speculative
1843  * type if any. CmpP should then go away.
1844  *
1845  * @param c  expected CmpP node
1846  * @return   result of CmpP on object casted to speculative type
1847  *
1848  */
optimize_cmp_with_klass(Node * c)1849 Node* Parse::optimize_cmp_with_klass(Node* c) {
1850   // If this is transformed by the _gvn to a comparison with the low
1851   // level klass then we may be able to use speculation
1852   if (c->Opcode() == Op_CmpP &&
1853       (c->in(1)->Opcode() == Op_LoadKlass || c->in(1)->Opcode() == Op_DecodeNKlass) &&
1854       c->in(2)->is_Con()) {
1855     Node* load_klass = NULL;
1856     Node* decode = NULL;
1857     if (c->in(1)->Opcode() == Op_DecodeNKlass) {
1858       decode = c->in(1);
1859       load_klass = c->in(1)->in(1);
1860     } else {
1861       load_klass = c->in(1);
1862     }
1863     if (load_klass->in(2)->is_AddP()) {
1864       Node* addp = load_klass->in(2);
1865       Node* obj = addp->in(AddPNode::Address);
1866       const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
1867       if (obj_type->speculative_type_not_null() != NULL) {
1868         ciKlass* k = obj_type->speculative_type();
1869         inc_sp(2);
1870         obj = maybe_cast_profiled_obj(obj, k);
1871         dec_sp(2);
1872         // Make the CmpP use the casted obj
1873         addp = basic_plus_adr(obj, addp->in(AddPNode::Offset));
1874         load_klass = load_klass->clone();
1875         load_klass->set_req(2, addp);
1876         load_klass = _gvn.transform(load_klass);
1877         if (decode != NULL) {
1878           decode = decode->clone();
1879           decode->set_req(1, load_klass);
1880           load_klass = _gvn.transform(decode);
1881         }
1882         c = c->clone();
1883         c->set_req(1, load_klass);
1884         c = _gvn.transform(c);
1885       }
1886     }
1887   }
1888   return c;
1889 }
1890 
1891 //------------------------------do_one_bytecode--------------------------------
1892 // Parse this bytecode, and alter the Parsers JVM->Node mapping
do_one_bytecode()1893 void Parse::do_one_bytecode() {
1894   Node *a, *b, *c, *d;          // Handy temps
1895   BoolTest::mask btest;
1896   int i;
1897 
1898   assert(!has_exceptions(), "bytecode entry state must be clear of throws");
1899 
1900   if (C->check_node_count(NodeLimitFudgeFactor * 5,
1901                           "out of nodes parsing method")) {
1902     return;
1903   }
1904 
1905 #ifdef ASSERT
1906   // for setting breakpoints
1907   if (TraceOptoParse) {
1908     tty->print(" @");
1909     dump_bci(bci());
1910     tty->cr();
1911   }
1912 #endif
1913 
1914   switch (bc()) {
1915   case Bytecodes::_nop:
1916     // do nothing
1917     break;
1918   case Bytecodes::_lconst_0:
1919     push_pair(longcon(0));
1920     break;
1921 
1922   case Bytecodes::_lconst_1:
1923     push_pair(longcon(1));
1924     break;
1925 
1926   case Bytecodes::_fconst_0:
1927     push(zerocon(T_FLOAT));
1928     break;
1929 
1930   case Bytecodes::_fconst_1:
1931     push(makecon(TypeF::ONE));
1932     break;
1933 
1934   case Bytecodes::_fconst_2:
1935     push(makecon(TypeF::make(2.0f)));
1936     break;
1937 
1938   case Bytecodes::_dconst_0:
1939     push_pair(zerocon(T_DOUBLE));
1940     break;
1941 
1942   case Bytecodes::_dconst_1:
1943     push_pair(makecon(TypeD::ONE));
1944     break;
1945 
1946   case Bytecodes::_iconst_m1:push(intcon(-1)); break;
1947   case Bytecodes::_iconst_0: push(intcon( 0)); break;
1948   case Bytecodes::_iconst_1: push(intcon( 1)); break;
1949   case Bytecodes::_iconst_2: push(intcon( 2)); break;
1950   case Bytecodes::_iconst_3: push(intcon( 3)); break;
1951   case Bytecodes::_iconst_4: push(intcon( 4)); break;
1952   case Bytecodes::_iconst_5: push(intcon( 5)); break;
1953   case Bytecodes::_bipush:   push(intcon(iter().get_constant_u1())); break;
1954   case Bytecodes::_sipush:   push(intcon(iter().get_constant_u2())); break;
1955   case Bytecodes::_aconst_null: push(null());  break;
1956   case Bytecodes::_ldc:
1957   case Bytecodes::_ldc_w:
1958   case Bytecodes::_ldc2_w:
1959     // If the constant is unresolved, run this BC once in the interpreter.
1960     {
1961       ciConstant constant = iter().get_constant();
1962       if (!constant.is_valid() ||
1963           (constant.basic_type() == T_OBJECT &&
1964            !constant.as_object()->is_loaded())) {
1965         int index = iter().get_constant_pool_index();
1966         constantTag tag = iter().get_constant_pool_tag(index);
1967         uncommon_trap(Deoptimization::make_trap_request
1968                       (Deoptimization::Reason_unloaded,
1969                        Deoptimization::Action_reinterpret,
1970                        index),
1971                       NULL, tag.internal_name());
1972         break;
1973       }
1974       assert(constant.basic_type() != T_OBJECT || constant.as_object()->is_instance(),
1975              "must be java_mirror of klass");
1976       const Type* con_type = Type::make_from_constant(constant);
1977       if (con_type != NULL) {
1978         push_node(con_type->basic_type(), makecon(con_type));
1979       }
1980     }
1981 
1982     break;
1983 
1984   case Bytecodes::_aload_0:
1985     push( local(0) );
1986     break;
1987   case Bytecodes::_aload_1:
1988     push( local(1) );
1989     break;
1990   case Bytecodes::_aload_2:
1991     push( local(2) );
1992     break;
1993   case Bytecodes::_aload_3:
1994     push( local(3) );
1995     break;
1996   case Bytecodes::_aload:
1997     push( local(iter().get_index()) );
1998     break;
1999 
2000   case Bytecodes::_fload_0:
2001   case Bytecodes::_iload_0:
2002     push( local(0) );
2003     break;
2004   case Bytecodes::_fload_1:
2005   case Bytecodes::_iload_1:
2006     push( local(1) );
2007     break;
2008   case Bytecodes::_fload_2:
2009   case Bytecodes::_iload_2:
2010     push( local(2) );
2011     break;
2012   case Bytecodes::_fload_3:
2013   case Bytecodes::_iload_3:
2014     push( local(3) );
2015     break;
2016   case Bytecodes::_fload:
2017   case Bytecodes::_iload:
2018     push( local(iter().get_index()) );
2019     break;
2020   case Bytecodes::_lload_0:
2021     push_pair_local( 0 );
2022     break;
2023   case Bytecodes::_lload_1:
2024     push_pair_local( 1 );
2025     break;
2026   case Bytecodes::_lload_2:
2027     push_pair_local( 2 );
2028     break;
2029   case Bytecodes::_lload_3:
2030     push_pair_local( 3 );
2031     break;
2032   case Bytecodes::_lload:
2033     push_pair_local( iter().get_index() );
2034     break;
2035 
2036   case Bytecodes::_dload_0:
2037     push_pair_local(0);
2038     break;
2039   case Bytecodes::_dload_1:
2040     push_pair_local(1);
2041     break;
2042   case Bytecodes::_dload_2:
2043     push_pair_local(2);
2044     break;
2045   case Bytecodes::_dload_3:
2046     push_pair_local(3);
2047     break;
2048   case Bytecodes::_dload:
2049     push_pair_local(iter().get_index());
2050     break;
2051   case Bytecodes::_fstore_0:
2052   case Bytecodes::_istore_0:
2053   case Bytecodes::_astore_0:
2054     set_local( 0, pop() );
2055     break;
2056   case Bytecodes::_fstore_1:
2057   case Bytecodes::_istore_1:
2058   case Bytecodes::_astore_1:
2059     set_local( 1, pop() );
2060     break;
2061   case Bytecodes::_fstore_2:
2062   case Bytecodes::_istore_2:
2063   case Bytecodes::_astore_2:
2064     set_local( 2, pop() );
2065     break;
2066   case Bytecodes::_fstore_3:
2067   case Bytecodes::_istore_3:
2068   case Bytecodes::_astore_3:
2069     set_local( 3, pop() );
2070     break;
2071   case Bytecodes::_fstore:
2072   case Bytecodes::_istore:
2073   case Bytecodes::_astore:
2074     set_local( iter().get_index(), pop() );
2075     break;
2076   // long stores
2077   case Bytecodes::_lstore_0:
2078     set_pair_local( 0, pop_pair() );
2079     break;
2080   case Bytecodes::_lstore_1:
2081     set_pair_local( 1, pop_pair() );
2082     break;
2083   case Bytecodes::_lstore_2:
2084     set_pair_local( 2, pop_pair() );
2085     break;
2086   case Bytecodes::_lstore_3:
2087     set_pair_local( 3, pop_pair() );
2088     break;
2089   case Bytecodes::_lstore:
2090     set_pair_local( iter().get_index(), pop_pair() );
2091     break;
2092 
2093   // double stores
2094   case Bytecodes::_dstore_0:
2095     set_pair_local( 0, dstore_rounding(pop_pair()) );
2096     break;
2097   case Bytecodes::_dstore_1:
2098     set_pair_local( 1, dstore_rounding(pop_pair()) );
2099     break;
2100   case Bytecodes::_dstore_2:
2101     set_pair_local( 2, dstore_rounding(pop_pair()) );
2102     break;
2103   case Bytecodes::_dstore_3:
2104     set_pair_local( 3, dstore_rounding(pop_pair()) );
2105     break;
2106   case Bytecodes::_dstore:
2107     set_pair_local( iter().get_index(), dstore_rounding(pop_pair()) );
2108     break;
2109 
2110   case Bytecodes::_pop:  dec_sp(1);   break;
2111   case Bytecodes::_pop2: dec_sp(2);   break;
2112   case Bytecodes::_swap:
2113     a = pop();
2114     b = pop();
2115     push(a);
2116     push(b);
2117     break;
2118   case Bytecodes::_dup:
2119     a = pop();
2120     push(a);
2121     push(a);
2122     break;
2123   case Bytecodes::_dup_x1:
2124     a = pop();
2125     b = pop();
2126     push( a );
2127     push( b );
2128     push( a );
2129     break;
2130   case Bytecodes::_dup_x2:
2131     a = pop();
2132     b = pop();
2133     c = pop();
2134     push( a );
2135     push( c );
2136     push( b );
2137     push( a );
2138     break;
2139   case Bytecodes::_dup2:
2140     a = pop();
2141     b = pop();
2142     push( b );
2143     push( a );
2144     push( b );
2145     push( a );
2146     break;
2147 
2148   case Bytecodes::_dup2_x1:
2149     // before: .. c, b, a
2150     // after:  .. b, a, c, b, a
2151     // not tested
2152     a = pop();
2153     b = pop();
2154     c = pop();
2155     push( b );
2156     push( a );
2157     push( c );
2158     push( b );
2159     push( a );
2160     break;
2161   case Bytecodes::_dup2_x2:
2162     // before: .. d, c, b, a
2163     // after:  .. b, a, d, c, b, a
2164     // not tested
2165     a = pop();
2166     b = pop();
2167     c = pop();
2168     d = pop();
2169     push( b );
2170     push( a );
2171     push( d );
2172     push( c );
2173     push( b );
2174     push( a );
2175     break;
2176 
2177   case Bytecodes::_arraylength: {
2178     // Must do null-check with value on expression stack
2179     Node *ary = null_check(peek(), T_ARRAY);
2180     // Compile-time detect of null-exception?
2181     if (stopped())  return;
2182     a = pop();
2183     push(load_array_length(a));
2184     break;
2185   }
2186 
2187   case Bytecodes::_baload:  array_load(T_BYTE);    break;
2188   case Bytecodes::_caload:  array_load(T_CHAR);    break;
2189   case Bytecodes::_iaload:  array_load(T_INT);     break;
2190   case Bytecodes::_saload:  array_load(T_SHORT);   break;
2191   case Bytecodes::_faload:  array_load(T_FLOAT);   break;
2192   case Bytecodes::_aaload:  array_load(T_OBJECT);  break;
2193   case Bytecodes::_laload:  array_load(T_LONG);    break;
2194   case Bytecodes::_daload:  array_load(T_DOUBLE);  break;
2195   case Bytecodes::_bastore: array_store(T_BYTE);   break;
2196   case Bytecodes::_castore: array_store(T_CHAR);   break;
2197   case Bytecodes::_iastore: array_store(T_INT);    break;
2198   case Bytecodes::_sastore: array_store(T_SHORT);  break;
2199   case Bytecodes::_fastore: array_store(T_FLOAT);  break;
2200   case Bytecodes::_aastore: array_store(T_OBJECT); break;
2201   case Bytecodes::_lastore: array_store(T_LONG);   break;
2202   case Bytecodes::_dastore: array_store(T_DOUBLE); break;
2203 
2204   case Bytecodes::_getfield:
2205     do_getfield();
2206     break;
2207 
2208   case Bytecodes::_getstatic:
2209     do_getstatic();
2210     break;
2211 
2212   case Bytecodes::_putfield:
2213     do_putfield();
2214     break;
2215 
2216   case Bytecodes::_putstatic:
2217     do_putstatic();
2218     break;
2219 
2220   case Bytecodes::_irem:
2221     do_irem();
2222     break;
2223   case Bytecodes::_idiv:
2224     // Must keep both values on the expression-stack during null-check
2225     zero_check_int(peek());
2226     // Compile-time detect of null-exception?
2227     if (stopped())  return;
2228     b = pop();
2229     a = pop();
2230     push( _gvn.transform( new DivINode(control(),a,b) ) );
2231     break;
2232   case Bytecodes::_imul:
2233     b = pop(); a = pop();
2234     push( _gvn.transform( new MulINode(a,b) ) );
2235     break;
2236   case Bytecodes::_iadd:
2237     b = pop(); a = pop();
2238     push( _gvn.transform( new AddINode(a,b) ) );
2239     break;
2240   case Bytecodes::_ineg:
2241     a = pop();
2242     push( _gvn.transform( new SubINode(_gvn.intcon(0),a)) );
2243     break;
2244   case Bytecodes::_isub:
2245     b = pop(); a = pop();
2246     push( _gvn.transform( new SubINode(a,b) ) );
2247     break;
2248   case Bytecodes::_iand:
2249     b = pop(); a = pop();
2250     push( _gvn.transform( new AndINode(a,b) ) );
2251     break;
2252   case Bytecodes::_ior:
2253     b = pop(); a = pop();
2254     push( _gvn.transform( new OrINode(a,b) ) );
2255     break;
2256   case Bytecodes::_ixor:
2257     b = pop(); a = pop();
2258     push( _gvn.transform( new XorINode(a,b) ) );
2259     break;
2260   case Bytecodes::_ishl:
2261     b = pop(); a = pop();
2262     push( _gvn.transform( new LShiftINode(a,b) ) );
2263     break;
2264   case Bytecodes::_ishr:
2265     b = pop(); a = pop();
2266     push( _gvn.transform( new RShiftINode(a,b) ) );
2267     break;
2268   case Bytecodes::_iushr:
2269     b = pop(); a = pop();
2270     push( _gvn.transform( new URShiftINode(a,b) ) );
2271     break;
2272 
2273   case Bytecodes::_fneg:
2274     a = pop();
2275     b = _gvn.transform(new NegFNode (a));
2276     push(b);
2277     break;
2278 
2279   case Bytecodes::_fsub:
2280     b = pop();
2281     a = pop();
2282     c = _gvn.transform( new SubFNode(a,b) );
2283     d = precision_rounding(c);
2284     push( d );
2285     break;
2286 
2287   case Bytecodes::_fadd:
2288     b = pop();
2289     a = pop();
2290     c = _gvn.transform( new AddFNode(a,b) );
2291     d = precision_rounding(c);
2292     push( d );
2293     break;
2294 
2295   case Bytecodes::_fmul:
2296     b = pop();
2297     a = pop();
2298     c = _gvn.transform( new MulFNode(a,b) );
2299     d = precision_rounding(c);
2300     push( d );
2301     break;
2302 
2303   case Bytecodes::_fdiv:
2304     b = pop();
2305     a = pop();
2306     c = _gvn.transform( new DivFNode(0,a,b) );
2307     d = precision_rounding(c);
2308     push( d );
2309     break;
2310 
2311   case Bytecodes::_frem:
2312     if (Matcher::has_match_rule(Op_ModF)) {
2313       // Generate a ModF node.
2314       b = pop();
2315       a = pop();
2316       c = _gvn.transform( new ModFNode(0,a,b) );
2317       d = precision_rounding(c);
2318       push( d );
2319     }
2320     else {
2321       // Generate a call.
2322       modf();
2323     }
2324     break;
2325 
2326   case Bytecodes::_fcmpl:
2327     b = pop();
2328     a = pop();
2329     c = _gvn.transform( new CmpF3Node( a, b));
2330     push(c);
2331     break;
2332   case Bytecodes::_fcmpg:
2333     b = pop();
2334     a = pop();
2335 
2336     // Same as fcmpl but need to flip the unordered case.  Swap the inputs,
2337     // which negates the result sign except for unordered.  Flip the unordered
2338     // as well by using CmpF3 which implements unordered-lesser instead of
2339     // unordered-greater semantics.  Finally, commute the result bits.  Result
2340     // is same as using a CmpF3Greater except we did it with CmpF3 alone.
2341     c = _gvn.transform( new CmpF3Node( b, a));
2342     c = _gvn.transform( new SubINode(_gvn.intcon(0),c) );
2343     push(c);
2344     break;
2345 
2346   case Bytecodes::_f2i:
2347     a = pop();
2348     push(_gvn.transform(new ConvF2INode(a)));
2349     break;
2350 
2351   case Bytecodes::_d2i:
2352     a = pop_pair();
2353     b = _gvn.transform(new ConvD2INode(a));
2354     push( b );
2355     break;
2356 
2357   case Bytecodes::_f2d:
2358     a = pop();
2359     b = _gvn.transform( new ConvF2DNode(a));
2360     push_pair( b );
2361     break;
2362 
2363   case Bytecodes::_d2f:
2364     a = pop_pair();
2365     b = _gvn.transform( new ConvD2FNode(a));
2366     // This breaks _227_mtrt (speed & correctness) and _222_mpegaudio (speed)
2367     //b = _gvn.transform(new RoundFloatNode(0, b) );
2368     push( b );
2369     break;
2370 
2371   case Bytecodes::_l2f:
2372     if (Matcher::convL2FSupported()) {
2373       a = pop_pair();
2374       b = _gvn.transform( new ConvL2FNode(a));
2375       // For i486.ad, FILD doesn't restrict precision to 24 or 53 bits.
2376       // Rather than storing the result into an FP register then pushing
2377       // out to memory to round, the machine instruction that implements
2378       // ConvL2D is responsible for rounding.
2379       // c = precision_rounding(b);
2380       c = _gvn.transform(b);
2381       push(c);
2382     } else {
2383       l2f();
2384     }
2385     break;
2386 
2387   case Bytecodes::_l2d:
2388     a = pop_pair();
2389     b = _gvn.transform( new ConvL2DNode(a));
2390     // For i486.ad, rounding is always necessary (see _l2f above).
2391     // c = dprecision_rounding(b);
2392     c = _gvn.transform(b);
2393     push_pair(c);
2394     break;
2395 
2396   case Bytecodes::_f2l:
2397     a = pop();
2398     b = _gvn.transform( new ConvF2LNode(a));
2399     push_pair(b);
2400     break;
2401 
2402   case Bytecodes::_d2l:
2403     a = pop_pair();
2404     b = _gvn.transform( new ConvD2LNode(a));
2405     push_pair(b);
2406     break;
2407 
2408   case Bytecodes::_dsub:
2409     b = pop_pair();
2410     a = pop_pair();
2411     c = _gvn.transform( new SubDNode(a,b) );
2412     d = dprecision_rounding(c);
2413     push_pair( d );
2414     break;
2415 
2416   case Bytecodes::_dadd:
2417     b = pop_pair();
2418     a = pop_pair();
2419     c = _gvn.transform( new AddDNode(a,b) );
2420     d = dprecision_rounding(c);
2421     push_pair( d );
2422     break;
2423 
2424   case Bytecodes::_dmul:
2425     b = pop_pair();
2426     a = pop_pair();
2427     c = _gvn.transform( new MulDNode(a,b) );
2428     d = dprecision_rounding(c);
2429     push_pair( d );
2430     break;
2431 
2432   case Bytecodes::_ddiv:
2433     b = pop_pair();
2434     a = pop_pair();
2435     c = _gvn.transform( new DivDNode(0,a,b) );
2436     d = dprecision_rounding(c);
2437     push_pair( d );
2438     break;
2439 
2440   case Bytecodes::_dneg:
2441     a = pop_pair();
2442     b = _gvn.transform(new NegDNode (a));
2443     push_pair(b);
2444     break;
2445 
2446   case Bytecodes::_drem:
2447     if (Matcher::has_match_rule(Op_ModD)) {
2448       // Generate a ModD node.
2449       b = pop_pair();
2450       a = pop_pair();
2451       // a % b
2452 
2453       c = _gvn.transform( new ModDNode(0,a,b) );
2454       d = dprecision_rounding(c);
2455       push_pair( d );
2456     }
2457     else {
2458       // Generate a call.
2459       modd();
2460     }
2461     break;
2462 
2463   case Bytecodes::_dcmpl:
2464     b = pop_pair();
2465     a = pop_pair();
2466     c = _gvn.transform( new CmpD3Node( a, b));
2467     push(c);
2468     break;
2469 
2470   case Bytecodes::_dcmpg:
2471     b = pop_pair();
2472     a = pop_pair();
2473     // Same as dcmpl but need to flip the unordered case.
2474     // Commute the inputs, which negates the result sign except for unordered.
2475     // Flip the unordered as well by using CmpD3 which implements
2476     // unordered-lesser instead of unordered-greater semantics.
2477     // Finally, negate the result bits.  Result is same as using a
2478     // CmpD3Greater except we did it with CmpD3 alone.
2479     c = _gvn.transform( new CmpD3Node( b, a));
2480     c = _gvn.transform( new SubINode(_gvn.intcon(0),c) );
2481     push(c);
2482     break;
2483 
2484 
2485     // Note for longs -> lo word is on TOS, hi word is on TOS - 1
2486   case Bytecodes::_land:
2487     b = pop_pair();
2488     a = pop_pair();
2489     c = _gvn.transform( new AndLNode(a,b) );
2490     push_pair(c);
2491     break;
2492   case Bytecodes::_lor:
2493     b = pop_pair();
2494     a = pop_pair();
2495     c = _gvn.transform( new OrLNode(a,b) );
2496     push_pair(c);
2497     break;
2498   case Bytecodes::_lxor:
2499     b = pop_pair();
2500     a = pop_pair();
2501     c = _gvn.transform( new XorLNode(a,b) );
2502     push_pair(c);
2503     break;
2504 
2505   case Bytecodes::_lshl:
2506     b = pop();                  // the shift count
2507     a = pop_pair();             // value to be shifted
2508     c = _gvn.transform( new LShiftLNode(a,b) );
2509     push_pair(c);
2510     break;
2511   case Bytecodes::_lshr:
2512     b = pop();                  // the shift count
2513     a = pop_pair();             // value to be shifted
2514     c = _gvn.transform( new RShiftLNode(a,b) );
2515     push_pair(c);
2516     break;
2517   case Bytecodes::_lushr:
2518     b = pop();                  // the shift count
2519     a = pop_pair();             // value to be shifted
2520     c = _gvn.transform( new URShiftLNode(a,b) );
2521     push_pair(c);
2522     break;
2523   case Bytecodes::_lmul:
2524     b = pop_pair();
2525     a = pop_pair();
2526     c = _gvn.transform( new MulLNode(a,b) );
2527     push_pair(c);
2528     break;
2529 
2530   case Bytecodes::_lrem:
2531     // Must keep both values on the expression-stack during null-check
2532     assert(peek(0) == top(), "long word order");
2533     zero_check_long(peek(1));
2534     // Compile-time detect of null-exception?
2535     if (stopped())  return;
2536     b = pop_pair();
2537     a = pop_pair();
2538     c = _gvn.transform( new ModLNode(control(),a,b) );
2539     push_pair(c);
2540     break;
2541 
2542   case Bytecodes::_ldiv:
2543     // Must keep both values on the expression-stack during null-check
2544     assert(peek(0) == top(), "long word order");
2545     zero_check_long(peek(1));
2546     // Compile-time detect of null-exception?
2547     if (stopped())  return;
2548     b = pop_pair();
2549     a = pop_pair();
2550     c = _gvn.transform( new DivLNode(control(),a,b) );
2551     push_pair(c);
2552     break;
2553 
2554   case Bytecodes::_ladd:
2555     b = pop_pair();
2556     a = pop_pair();
2557     c = _gvn.transform( new AddLNode(a,b) );
2558     push_pair(c);
2559     break;
2560   case Bytecodes::_lsub:
2561     b = pop_pair();
2562     a = pop_pair();
2563     c = _gvn.transform( new SubLNode(a,b) );
2564     push_pair(c);
2565     break;
2566   case Bytecodes::_lcmp:
2567     // Safepoints are now inserted _before_ branches.  The long-compare
2568     // bytecode painfully produces a 3-way value (-1,0,+1) which requires a
2569     // slew of control flow.  These are usually followed by a CmpI vs zero and
2570     // a branch; this pattern then optimizes to the obvious long-compare and
2571     // branch.  However, if the branch is backwards there's a Safepoint
2572     // inserted.  The inserted Safepoint captures the JVM state at the
2573     // pre-branch point, i.e. it captures the 3-way value.  Thus if a
2574     // long-compare is used to control a loop the debug info will force
2575     // computation of the 3-way value, even though the generated code uses a
2576     // long-compare and branch.  We try to rectify the situation by inserting
2577     // a SafePoint here and have it dominate and kill the safepoint added at a
2578     // following backwards branch.  At this point the JVM state merely holds 2
2579     // longs but not the 3-way value.
2580     if( UseLoopSafepoints ) {
2581       switch( iter().next_bc() ) {
2582       case Bytecodes::_ifgt:
2583       case Bytecodes::_iflt:
2584       case Bytecodes::_ifge:
2585       case Bytecodes::_ifle:
2586       case Bytecodes::_ifne:
2587       case Bytecodes::_ifeq:
2588         // If this is a backwards branch in the bytecodes, add Safepoint
2589         maybe_add_safepoint(iter().next_get_dest());
2590       default:
2591         break;
2592       }
2593     }
2594     b = pop_pair();
2595     a = pop_pair();
2596     c = _gvn.transform( new CmpL3Node( a, b ));
2597     push(c);
2598     break;
2599 
2600   case Bytecodes::_lneg:
2601     a = pop_pair();
2602     b = _gvn.transform( new SubLNode(longcon(0),a));
2603     push_pair(b);
2604     break;
2605   case Bytecodes::_l2i:
2606     a = pop_pair();
2607     push( _gvn.transform( new ConvL2INode(a)));
2608     break;
2609   case Bytecodes::_i2l:
2610     a = pop();
2611     b = _gvn.transform( new ConvI2LNode(a));
2612     push_pair(b);
2613     break;
2614   case Bytecodes::_i2b:
2615     // Sign extend
2616     a = pop();
2617     a = _gvn.transform( new LShiftINode(a,_gvn.intcon(24)) );
2618     a = _gvn.transform( new RShiftINode(a,_gvn.intcon(24)) );
2619     push( a );
2620     break;
2621   case Bytecodes::_i2s:
2622     a = pop();
2623     a = _gvn.transform( new LShiftINode(a,_gvn.intcon(16)) );
2624     a = _gvn.transform( new RShiftINode(a,_gvn.intcon(16)) );
2625     push( a );
2626     break;
2627   case Bytecodes::_i2c:
2628     a = pop();
2629     push( _gvn.transform( new AndINode(a,_gvn.intcon(0xFFFF)) ) );
2630     break;
2631 
2632   case Bytecodes::_i2f:
2633     a = pop();
2634     b = _gvn.transform( new ConvI2FNode(a) ) ;
2635     c = precision_rounding(b);
2636     push (b);
2637     break;
2638 
2639   case Bytecodes::_i2d:
2640     a = pop();
2641     b = _gvn.transform( new ConvI2DNode(a));
2642     push_pair(b);
2643     break;
2644 
2645   case Bytecodes::_iinc:        // Increment local
2646     i = iter().get_index();     // Get local index
2647     set_local( i, _gvn.transform( new AddINode( _gvn.intcon(iter().get_iinc_con()), local(i) ) ) );
2648     break;
2649 
2650   // Exit points of synchronized methods must have an unlock node
2651   case Bytecodes::_return:
2652     return_current(NULL);
2653     break;
2654 
2655   case Bytecodes::_ireturn:
2656   case Bytecodes::_areturn:
2657   case Bytecodes::_freturn:
2658     return_current(pop());
2659     break;
2660   case Bytecodes::_lreturn:
2661     return_current(pop_pair());
2662     break;
2663   case Bytecodes::_dreturn:
2664     return_current(pop_pair());
2665     break;
2666 
2667   case Bytecodes::_athrow:
2668     // null exception oop throws NULL pointer exception
2669     null_check(peek());
2670     if (stopped())  return;
2671     // Hook the thrown exception directly to subsequent handlers.
2672     if (BailoutToInterpreterForThrows) {
2673       // Keep method interpreted from now on.
2674       uncommon_trap(Deoptimization::Reason_unhandled,
2675                     Deoptimization::Action_make_not_compilable);
2676       return;
2677     }
2678     if (env()->jvmti_can_post_on_exceptions()) {
2679       // check if we must post exception events, take uncommon trap if so (with must_throw = false)
2680       uncommon_trap_if_should_post_on_exceptions(Deoptimization::Reason_unhandled, false);
2681     }
2682     // Here if either can_post_on_exceptions or should_post_on_exceptions is false
2683     add_exception_state(make_exception_state(peek()));
2684     break;
2685 
2686   case Bytecodes::_goto:   // fall through
2687   case Bytecodes::_goto_w: {
2688     int target_bci = (bc() == Bytecodes::_goto) ? iter().get_dest() : iter().get_far_dest();
2689 
2690     // If this is a backwards branch in the bytecodes, add Safepoint
2691     maybe_add_safepoint(target_bci);
2692 
2693     // Update method data
2694     profile_taken_branch(target_bci);
2695 
2696     // Merge the current control into the target basic block
2697     merge(target_bci);
2698 
2699     // See if we can get some profile data and hand it off to the next block
2700     Block *target_block = block()->successor_for_bci(target_bci);
2701     if (target_block->pred_count() != 1)  break;
2702     ciMethodData* methodData = method()->method_data();
2703     if (!methodData->is_mature())  break;
2704     ciProfileData* data = methodData->bci_to_data(bci());
2705     assert(data != NULL && data->is_JumpData(), "need JumpData for taken branch");
2706     int taken = ((ciJumpData*)data)->taken();
2707     taken = method()->scale_count(taken);
2708     target_block->set_count(taken);
2709     break;
2710   }
2711 
2712   case Bytecodes::_ifnull:    btest = BoolTest::eq; goto handle_if_null;
2713   case Bytecodes::_ifnonnull: btest = BoolTest::ne; goto handle_if_null;
2714   handle_if_null:
2715     // If this is a backwards branch in the bytecodes, add Safepoint
2716     maybe_add_safepoint(iter().get_dest());
2717     a = null();
2718     b = pop();
2719     if (!_gvn.type(b)->speculative_maybe_null() &&
2720         !too_many_traps(Deoptimization::Reason_speculate_null_check)) {
2721       inc_sp(1);
2722       Node* null_ctl = top();
2723       b = null_check_oop(b, &null_ctl, true, true, true);
2724       assert(null_ctl->is_top(), "no null control here");
2725       dec_sp(1);
2726     } else if (_gvn.type(b)->speculative_always_null() &&
2727                !too_many_traps(Deoptimization::Reason_speculate_null_assert)) {
2728       inc_sp(1);
2729       b = null_assert(b);
2730       dec_sp(1);
2731     }
2732     c = _gvn.transform( new CmpPNode(b, a) );
2733     do_ifnull(btest, c);
2734     break;
2735 
2736   case Bytecodes::_if_acmpeq: btest = BoolTest::eq; goto handle_if_acmp;
2737   case Bytecodes::_if_acmpne: btest = BoolTest::ne; goto handle_if_acmp;
2738   handle_if_acmp:
2739     // If this is a backwards branch in the bytecodes, add Safepoint
2740     maybe_add_safepoint(iter().get_dest());
2741     a = access_resolve(pop(), 0);
2742     b = access_resolve(pop(), 0);
2743     c = _gvn.transform( new CmpPNode(b, a) );
2744     c = optimize_cmp_with_klass(c);
2745     do_if(btest, c);
2746     break;
2747 
2748   case Bytecodes::_ifeq: btest = BoolTest::eq; goto handle_ifxx;
2749   case Bytecodes::_ifne: btest = BoolTest::ne; goto handle_ifxx;
2750   case Bytecodes::_iflt: btest = BoolTest::lt; goto handle_ifxx;
2751   case Bytecodes::_ifle: btest = BoolTest::le; goto handle_ifxx;
2752   case Bytecodes::_ifgt: btest = BoolTest::gt; goto handle_ifxx;
2753   case Bytecodes::_ifge: btest = BoolTest::ge; goto handle_ifxx;
2754   handle_ifxx:
2755     // If this is a backwards branch in the bytecodes, add Safepoint
2756     maybe_add_safepoint(iter().get_dest());
2757     a = _gvn.intcon(0);
2758     b = pop();
2759     c = _gvn.transform( new CmpINode(b, a) );
2760     do_if(btest, c);
2761     break;
2762 
2763   case Bytecodes::_if_icmpeq: btest = BoolTest::eq; goto handle_if_icmp;
2764   case Bytecodes::_if_icmpne: btest = BoolTest::ne; goto handle_if_icmp;
2765   case Bytecodes::_if_icmplt: btest = BoolTest::lt; goto handle_if_icmp;
2766   case Bytecodes::_if_icmple: btest = BoolTest::le; goto handle_if_icmp;
2767   case Bytecodes::_if_icmpgt: btest = BoolTest::gt; goto handle_if_icmp;
2768   case Bytecodes::_if_icmpge: btest = BoolTest::ge; goto handle_if_icmp;
2769   handle_if_icmp:
2770     // If this is a backwards branch in the bytecodes, add Safepoint
2771     maybe_add_safepoint(iter().get_dest());
2772     a = pop();
2773     b = pop();
2774     c = _gvn.transform( new CmpINode( b, a ) );
2775     do_if(btest, c);
2776     break;
2777 
2778   case Bytecodes::_tableswitch:
2779     do_tableswitch();
2780     break;
2781 
2782   case Bytecodes::_lookupswitch:
2783     do_lookupswitch();
2784     break;
2785 
2786   case Bytecodes::_invokestatic:
2787   case Bytecodes::_invokedynamic:
2788   case Bytecodes::_invokespecial:
2789   case Bytecodes::_invokevirtual:
2790   case Bytecodes::_invokeinterface:
2791     do_call();
2792     break;
2793   case Bytecodes::_checkcast:
2794     do_checkcast();
2795     break;
2796   case Bytecodes::_instanceof:
2797     do_instanceof();
2798     break;
2799   case Bytecodes::_anewarray:
2800     do_anewarray();
2801     break;
2802   case Bytecodes::_newarray:
2803     do_newarray((BasicType)iter().get_index());
2804     break;
2805   case Bytecodes::_multianewarray:
2806     do_multianewarray();
2807     break;
2808   case Bytecodes::_new:
2809     do_new();
2810     break;
2811 
2812   case Bytecodes::_jsr:
2813   case Bytecodes::_jsr_w:
2814     do_jsr();
2815     break;
2816 
2817   case Bytecodes::_ret:
2818     do_ret();
2819     break;
2820 
2821 
2822   case Bytecodes::_monitorenter:
2823     do_monitor_enter();
2824     break;
2825 
2826   case Bytecodes::_monitorexit:
2827     do_monitor_exit();
2828     break;
2829 
2830   case Bytecodes::_breakpoint:
2831     // Breakpoint set concurrently to compile
2832     // %%% use an uncommon trap?
2833     C->record_failure("breakpoint in method");
2834     return;
2835 
2836   default:
2837 #ifndef PRODUCT
2838     map()->dump(99);
2839 #endif
2840     tty->print("\nUnhandled bytecode %s\n", Bytecodes::name(bc()) );
2841     ShouldNotReachHere();
2842   }
2843 
2844 #ifndef PRODUCT
2845   IdealGraphPrinter *printer = C->printer();
2846   if (printer && printer->should_print(1)) {
2847     char buffer[256];
2848     jio_snprintf(buffer, sizeof(buffer), "Bytecode %d: %s", bci(), Bytecodes::name(bc()));
2849     bool old = printer->traverse_outs();
2850     printer->set_traverse_outs(true);
2851     printer->print_method(buffer, 4);
2852     printer->set_traverse_outs(old);
2853   }
2854 #endif
2855 }
2856