jdk8-mips64-public/hotspot: src/share/vm/opto/parse2.cpp@beebba0acc11 (annotated)

src/share/vm/opto/parse2.cpp@beebba0acc11 (annotated)

src/share/vm/opto/parse2.cpp

Mon, 26 Nov 2012 17:25:11 -0800

author: twisti
date: Mon, 26 Nov 2012 17:25:11 -0800
changeset 4313: beebba0acc11
parent 4159: 8e47bac5643a
child 4862: e370f63dc5b1
permissions: -rw-r--r--

7172640: C2: instrinsic implementations in LibraryCallKit should use argument() instead of pop()
Reviewed-by: kvn, jrose

 /*
  * Copyright (c) 1998, 2012, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #include "precompiled.hpp"
 #include "ci/ciMethodData.hpp"
 #include "classfile/systemDictionary.hpp"
 #include "classfile/vmSymbols.hpp"
 #include "compiler/compileLog.hpp"
 #include "interpreter/linkResolver.hpp"
 #include "memory/universe.inline.hpp"
 #include "opto/addnode.hpp"
 #include "opto/divnode.hpp"
 #include "opto/idealGraphPrinter.hpp"
 #include "opto/matcher.hpp"
 #include "opto/memnode.hpp"
 #include "opto/mulnode.hpp"
 #include "opto/parse.hpp"
 #include "opto/runtime.hpp"
 #include "runtime/deoptimization.hpp"
 #include "runtime/sharedRuntime.hpp"
 extern int explicit_null_checks_inserted,
            explicit_null_checks_elided;
 //---------------------------------array_load----------------------------------
 void Parse::array_load(BasicType elem_type) {
   const Type* elem = Type::TOP;
   Node* adr = array_addressing(elem_type, 0, &elem);
   if (stopped())  return;     // guaranteed null or range check
   dec_sp(2);                  // Pop array and index
   const TypeAryPtr* adr_type = TypeAryPtr::get_array_body_type(elem_type);
   Node* ld = make_load(control(), adr, elem, elem_type, adr_type);
   push(ld);
 }
 //--------------------------------array_store----------------------------------
 void Parse::array_store(BasicType elem_type) {
   Node* adr = array_addressing(elem_type, 1);
   if (stopped())  return;     // guaranteed null or range check
   Node* val = pop();
   dec_sp(2);                  // Pop array and index
   const TypeAryPtr* adr_type = TypeAryPtr::get_array_body_type(elem_type);
   store_to_memory(control(), adr, val, elem_type, adr_type);
 }
 //------------------------------array_addressing-------------------------------
 // Pull array and index from the stack.  Compute pointer-to-element.
 Node* Parse::array_addressing(BasicType type, int vals, const Type* *result2) {
   Node *idx   = peek(0+vals);   // Get from stack without popping
   Node *ary   = peek(1+vals);   // in case of exception
   // Null check the array base, with correct stack contents
   ary = null_check(ary, T_ARRAY);
   // Compile-time detect of null-exception?
   if (stopped())  return top();
   const TypeAryPtr* arytype  = _gvn.type(ary)->is_aryptr();
   const TypeInt*    sizetype = arytype->size();
   const Type*       elemtype = arytype->elem();
   if (UseUniqueSubclasses && result2 != NULL) {
     const Type* el = elemtype->make_ptr();
     if (el && el->isa_instptr()) {
       const TypeInstPtr* toop = el->is_instptr();
       if (toop->klass()->as_instance_klass()->unique_concrete_subklass()) {
         // If we load from "AbstractClass[]" we must see "ConcreteSubClass".
         const Type* subklass = Type::get_const_type(toop->klass());
         elemtype = subklass->join(el);
       }
     }
   }
   // Check for big class initializers with all constant offsets
   // feeding into a known-size array.
   const TypeInt* idxtype = _gvn.type(idx)->is_int();
   // See if the highest idx value is less than the lowest array bound,
   // and if the idx value cannot be negative:
   bool need_range_check = true;
   if (idxtype->_hi < sizetype->_lo && idxtype->_lo >= 0) {
     need_range_check = false;
     if (C->log() != NULL)   C->log()->elem("observe that='!need_range_check'");
   }
   if (!arytype->klass()->is_loaded()) {
     // Only fails for some -Xcomp runs
     // The class is unloaded.  We have to run this bytecode in the interpreter.
     uncommon_trap(Deoptimization::Reason_unloaded,
                   Deoptimization::Action_reinterpret,
                   arytype->klass(), "!loaded array");
     return top();
   }
   // Do the range check
   if (GenerateRangeChecks && need_range_check) {
     Node* tst;
     if (sizetype->_hi <= 0) {
       // The greatest array bound is negative, so we can conclude that we're
       // compiling unreachable code, but the unsigned compare trick used below
       // only works with non-negative lengths.  Instead, hack "tst" to be zero so
       // the uncommon_trap path will always be taken.
       tst = _gvn.intcon(0);
     } else {
       // Range is constant in array-oop, so we can use the original state of mem
       Node* len = load_array_length(ary);
       // Test length vs index (standard trick using unsigned compare)
       Node* chk = _gvn.transform( new (C) CmpUNode(idx, len) );
       BoolTest::mask btest = BoolTest::lt;
       tst = _gvn.transform( new (C) BoolNode(chk, btest) );
     }
     // Branch to failure if out of bounds
     { BuildCutout unless(this, tst, PROB_MAX);
       if (C->allow_range_check_smearing()) {
         // Do not use builtin_throw, since range checks are sometimes
         // made more stringent by an optimistic transformation.
         // This creates "tentative" range checks at this point,
         // which are not guaranteed to throw exceptions.
         // See IfNode::Ideal, is_range_check, adjust_check.
         uncommon_trap(Deoptimization::Reason_range_check,
                       Deoptimization::Action_make_not_entrant,
                       NULL, "range_check");
       } else {
         // If we have already recompiled with the range-check-widening
         // heroic optimization turned off, then we must really be throwing
         // range check exceptions.
         builtin_throw(Deoptimization::Reason_range_check, idx);
       }
     }
   }
   // Check for always knowing you are throwing a range-check exception
   if (stopped())  return top();
   Node* ptr = array_element_address(ary, idx, type, sizetype);
   if (result2 != NULL)  *result2 = elemtype;
   assert(ptr != top(), "top should go hand-in-hand with stopped");
   return ptr;
 }
 // returns IfNode
 IfNode* Parse::jump_if_fork_int(Node* a, Node* b, BoolTest::mask mask) {
   Node   *cmp = _gvn.transform( new (C) CmpINode( a, b)); // two cases: shiftcount > 32 and shiftcount <= 32
   Node   *tst = _gvn.transform( new (C) BoolNode( cmp, mask));
   IfNode *iff = create_and_map_if( control(), tst, ((mask == BoolTest::eq) ? PROB_STATIC_INFREQUENT : PROB_FAIR), COUNT_UNKNOWN );
   return iff;
 }
 // return Region node
 Node* Parse::jump_if_join(Node* iffalse, Node* iftrue) {
   Node *region  = new (C) RegionNode(3); // 2 results
   record_for_igvn(region);
   region->init_req(1, iffalse);
   region->init_req(2, iftrue );
   _gvn.set_type(region, Type::CONTROL);
   region = _gvn.transform(region);
   set_control (region);
   return region;
 }
 //------------------------------helper for tableswitch-------------------------
 void Parse::jump_if_true_fork(IfNode *iff, int dest_bci_if_true, int prof_table_index) {
   // True branch, use existing map info
   { PreserveJVMState pjvms(this);
     Node *iftrue  = _gvn.transform( new (C) IfTrueNode (iff) );
     set_control( iftrue );
     profile_switch_case(prof_table_index);
     merge_new_path(dest_bci_if_true);
   }
   // False branch
   Node *iffalse = _gvn.transform( new (C) IfFalseNode(iff) );
   set_control( iffalse );
 }
 void Parse::jump_if_false_fork(IfNode *iff, int dest_bci_if_true, int prof_table_index) {
   // True branch, use existing map info
   { PreserveJVMState pjvms(this);
     Node *iffalse  = _gvn.transform( new (C) IfFalseNode (iff) );
     set_control( iffalse );
     profile_switch_case(prof_table_index);
     merge_new_path(dest_bci_if_true);
   }
   // False branch
   Node *iftrue = _gvn.transform( new (C) IfTrueNode(iff) );
   set_control( iftrue );
 }
 void Parse::jump_if_always_fork(int dest_bci, int prof_table_index) {
   // False branch, use existing map and control()
   profile_switch_case(prof_table_index);
   merge_new_path(dest_bci);
 }
 extern "C" {
   static int jint_cmp(const void *i, const void *j) {
     int a = *(jint *)i;
     int b = *(jint *)j;
     return a > b ? 1 : a < b ? -1 : 0;
   }
 }
 // Default value for methodData switch indexing. Must be a negative value to avoid
 // conflict with any legal switch index.
 #define NullTableIndex -1
 class SwitchRange : public StackObj {
   // a range of integers coupled with a bci destination
   jint _lo;                     // inclusive lower limit
   jint _hi;                     // inclusive upper limit
   int _dest;
   int _table_index;             // index into method data table
 public:
   jint lo() const              { return _lo;   }
   jint hi() const              { return _hi;   }
   int  dest() const            { return _dest; }
   int  table_index() const     { return _table_index; }
   bool is_singleton() const    { return _lo == _hi; }
   void setRange(jint lo, jint hi, int dest, int table_index) {
     assert(lo <= hi, "must be a non-empty range");
     _lo = lo, _hi = hi; _dest = dest; _table_index = table_index;
   }
   bool adjoinRange(jint lo, jint hi, int dest, int table_index) {
     assert(lo <= hi, "must be a non-empty range");
     if (lo == _hi+1 && dest == _dest && table_index == _table_index) {
       _hi = hi;
       return true;
     }
     return false;
   }
   void set (jint value, int dest, int table_index) {
     setRange(value, value, dest, table_index);
   }
   bool adjoin(jint value, int dest, int table_index) {
     return adjoinRange(value, value, dest, table_index);
   }
   void print(ciEnv* env) {
     if (is_singleton())
       tty->print(" {%d}=>%d", lo(), dest());
     else if (lo() == min_jint)
       tty->print(" {..%d}=>%d", hi(), dest());
     else if (hi() == max_jint)
       tty->print(" {%d..}=>%d", lo(), dest());
     else
       tty->print(" {%d..%d}=>%d", lo(), hi(), dest());
   }
 };
 //-------------------------------do_tableswitch--------------------------------
 void Parse::do_tableswitch() {
   Node* lookup = pop();
   // Get information about tableswitch
   int default_dest = iter().get_dest_table(0);
   int lo_index     = iter().get_int_table(1);
   int hi_index     = iter().get_int_table(2);
   int len          = hi_index - lo_index + 1;
   if (len < 1) {
     // If this is a backward branch, add safepoint
     maybe_add_safepoint(default_dest);
     merge(default_dest);
     return;
   }
   // generate decision tree, using trichotomy when possible
   int rnum = len+2;
   bool makes_backward_branch = false;
   SwitchRange* ranges = NEW_RESOURCE_ARRAY(SwitchRange, rnum);
   int rp = -1;
   if (lo_index != min_jint) {
     ranges[++rp].setRange(min_jint, lo_index-1, default_dest, NullTableIndex);
   }
   for (int j = 0; j < len; j++) {
     jint match_int = lo_index+j;
     int  dest      = iter().get_dest_table(j+3);
     makes_backward_branch |= (dest <= bci());
     int  table_index = method_data_update() ? j : NullTableIndex;
     if (rp < 0 || !ranges[rp].adjoin(match_int, dest, table_index)) {
       ranges[++rp].set(match_int, dest, table_index);
     }
   }
   jint highest = lo_index+(len-1);
   assert(ranges[rp].hi() == highest, "");
   if (highest != max_jint
       && !ranges[rp].adjoinRange(highest+1, max_jint, default_dest, NullTableIndex)) {
     ranges[++rp].setRange(highest+1, max_jint, default_dest, NullTableIndex);
   }
   assert(rp < len+2, "not too many ranges");
   // Safepoint in case if backward branch observed
   if( makes_backward_branch && UseLoopSafepoints )
     add_safepoint();
   jump_switch_ranges(lookup, &ranges[0], &ranges[rp]);
 }
 //------------------------------do_lookupswitch--------------------------------
 void Parse::do_lookupswitch() {
   Node *lookup = pop();         // lookup value
   // Get information about lookupswitch
   int default_dest = iter().get_dest_table(0);
   int len          = iter().get_int_table(1);
   if (len < 1) {    // If this is a backward branch, add safepoint
     maybe_add_safepoint(default_dest);
     merge(default_dest);
     return;
   }
   // generate decision tree, using trichotomy when possible
   jint* table = NEW_RESOURCE_ARRAY(jint, len*2);
   {
     for( int j = 0; j < len; j++ ) {
       table[j+j+0] = iter().get_int_table(2+j+j);
       table[j+j+1] = iter().get_dest_table(2+j+j+1);
     }
     qsort( table, len, 2*sizeof(table[0]), jint_cmp );
   }
   int rnum = len*2+1;
   bool makes_backward_branch = false;
   SwitchRange* ranges = NEW_RESOURCE_ARRAY(SwitchRange, rnum);
   int rp = -1;
   for( int j = 0; j < len; j++ ) {
     jint match_int   = table[j+j+0];
     int  dest        = table[j+j+1];
     int  next_lo     = rp < 0 ? min_jint : ranges[rp].hi()+1;
     int  table_index = method_data_update() ? j : NullTableIndex;
     makes_backward_branch |= (dest <= bci());
     if( match_int != next_lo ) {
       ranges[++rp].setRange(next_lo, match_int-1, default_dest, NullTableIndex);
     }
     if( rp < 0 || !ranges[rp].adjoin(match_int, dest, table_index) ) {
       ranges[++rp].set(match_int, dest, table_index);
     }
   }
   jint highest = table[2*(len-1)];
   assert(ranges[rp].hi() == highest, "");
   if( highest != max_jint
       && !ranges[rp].adjoinRange(highest+1, max_jint, default_dest, NullTableIndex) ) {
     ranges[++rp].setRange(highest+1, max_jint, default_dest, NullTableIndex);
   }
   assert(rp < rnum, "not too many ranges");
   // Safepoint in case backward branch observed
   if( makes_backward_branch && UseLoopSafepoints )
     add_safepoint();
   jump_switch_ranges(lookup, &ranges[0], &ranges[rp]);
 }
 //----------------------------create_jump_tables-------------------------------
 bool Parse::create_jump_tables(Node* key_val, SwitchRange* lo, SwitchRange* hi) {
   // Are jumptables enabled
   if (!UseJumpTables)  return false;
   // Are jumptables supported
   if (!Matcher::has_match_rule(Op_Jump))  return false;
   // Don't make jump table if profiling
   if (method_data_update())  return false;
   // Decide if a guard is needed to lop off big ranges at either (or
   // both) end(s) of the input set. We'll call this the default target
   // even though we can't be sure that it is the true "default".
   bool needs_guard = false;
   int default_dest;
   int64 total_outlier_size = 0;
   int64 hi_size = ((int64)hi->hi()) - ((int64)hi->lo()) + 1;
   int64 lo_size = ((int64)lo->hi()) - ((int64)lo->lo()) + 1;
   if (lo->dest() == hi->dest()) {
     total_outlier_size = hi_size + lo_size;
     default_dest = lo->dest();
   } else if (lo_size > hi_size) {
     total_outlier_size = lo_size;
     default_dest = lo->dest();
   } else {
     total_outlier_size = hi_size;
     default_dest = hi->dest();
   }
   // If a guard test will eliminate very sparse end ranges, then
   // it is worth the cost of an extra jump.
   if (total_outlier_size > (MaxJumpTableSparseness * 4)) {
     needs_guard = true;
     if (default_dest == lo->dest()) lo++;
     if (default_dest == hi->dest()) hi--;
   }
   // Find the total number of cases and ranges
   int64 num_cases = ((int64)hi->hi()) - ((int64)lo->lo()) + 1;
   int num_range = hi - lo + 1;
   // Don't create table if: too large, too small, or too sparse.
   if (num_cases < MinJumpTableSize || num_cases > MaxJumpTableSize)
     return false;
   if (num_cases > (MaxJumpTableSparseness * num_range))
     return false;
   // Normalize table lookups to zero
   int lowval = lo->lo();
   key_val = _gvn.transform( new (C) SubINode(key_val, _gvn.intcon(lowval)) );
   // Generate a guard to protect against input keyvals that aren't
   // in the switch domain.
   if (needs_guard) {
     Node*   size = _gvn.intcon(num_cases);
     Node*   cmp = _gvn.transform( new (C) CmpUNode(key_val, size) );
     Node*   tst = _gvn.transform( new (C) BoolNode(cmp, BoolTest::ge) );
     IfNode* iff = create_and_map_if( control(), tst, PROB_FAIR, COUNT_UNKNOWN);
     jump_if_true_fork(iff, default_dest, NullTableIndex);
   }
   // Create an ideal node JumpTable that has projections
   // of all possible ranges for a switch statement
   // The key_val input must be converted to a pointer offset and scaled.
   // Compare Parse::array_addressing above.
 #ifdef _LP64
   // Clean the 32-bit int into a real 64-bit offset.
   // Otherwise, the jint value 0 might turn into an offset of 0x0800000000.
   const TypeLong* lkeytype = TypeLong::make(CONST64(0), num_cases-1, Type::WidenMin);
   key_val       = _gvn.transform( new (C) ConvI2LNode(key_val, lkeytype) );
 #endif
   // Shift the value by wordsize so we have an index into the table, rather
   // than a switch value
   Node *shiftWord = _gvn.MakeConX(wordSize);
   key_val = _gvn.transform( new (C) MulXNode( key_val, shiftWord));
   // Create the JumpNode
   Node* jtn = _gvn.transform( new (C) JumpNode(control(), key_val, num_cases) );
   // These are the switch destinations hanging off the jumpnode
   int i = 0;
   for (SwitchRange* r = lo; r <= hi; r++) {
     for (int j = r->lo(); j <= r->hi(); j++, i++) {
       Node* input = _gvn.transform(new (C) JumpProjNode(jtn, i, r->dest(), j - lowval));
       {
         PreserveJVMState pjvms(this);
         set_control(input);
         jump_if_always_fork(r->dest(), r->table_index());
       }
     }
   }
   assert(i == num_cases, "miscount of cases");
   stop_and_kill_map();  // no more uses for this JVMS
   return true;
 }
 //----------------------------jump_switch_ranges-------------------------------
 void Parse::jump_switch_ranges(Node* key_val, SwitchRange *lo, SwitchRange *hi, int switch_depth) {
   Block* switch_block = block();
   if (switch_depth == 0) {
     // Do special processing for the top-level call.
     assert(lo->lo() == min_jint, "initial range must exhaust Type::INT");
     assert(hi->hi() == max_jint, "initial range must exhaust Type::INT");
     // Decrement pred-numbers for the unique set of nodes.
 #ifdef ASSERT
     // Ensure that the block's successors are a (duplicate-free) set.
     int successors_counted = 0;  // block occurrences in [hi..lo]
     int unique_successors = switch_block->num_successors();
     for (int i = 0; i < unique_successors; i++) {
       Block* target = switch_block->successor_at(i);
       // Check that the set of successors is the same in both places.
       int successors_found = 0;
       for (SwitchRange* p = lo; p <= hi; p++) {
         if (p->dest() == target->start())  successors_found++;
       }
       assert(successors_found > 0, "successor must be known");
       successors_counted += successors_found;
     }
     assert(successors_counted == (hi-lo)+1, "no unexpected successors");
 #endif
     // Maybe prune the inputs, based on the type of key_val.
     jint min_val = min_jint;
     jint max_val = max_jint;
     const TypeInt* ti = key_val->bottom_type()->isa_int();
     if (ti != NULL) {
       min_val = ti->_lo;
       max_val = ti->_hi;
       assert(min_val <= max_val, "invalid int type");
     }
     while (lo->hi() < min_val)  lo++;
     if (lo->lo() < min_val)  lo->setRange(min_val, lo->hi(), lo->dest(), lo->table_index());
     while (hi->lo() > max_val)  hi--;
     if (hi->hi() > max_val)  hi->setRange(hi->lo(), max_val, hi->dest(), hi->table_index());
   }
 #ifndef PRODUCT
   if (switch_depth == 0) {
     _max_switch_depth = 0;
     _est_switch_depth = log2_intptr((hi-lo+1)-1)+1;
   }
 #endif
   assert(lo <= hi, "must be a non-empty set of ranges");
   if (lo == hi) {
     jump_if_always_fork(lo->dest(), lo->table_index());
   } else {
     assert(lo->hi() == (lo+1)->lo()-1, "contiguous ranges");
     assert(hi->lo() == (hi-1)->hi()+1, "contiguous ranges");
     if (create_jump_tables(key_val, lo, hi)) return;
     int nr = hi - lo + 1;
     SwitchRange* mid = lo + nr/2;
     // if there is an easy choice, pivot at a singleton:
     if (nr > 3 && !mid->is_singleton() && (mid-1)->is_singleton())  mid--;
     assert(lo < mid && mid <= hi, "good pivot choice");
     assert(nr != 2 || mid == hi,   "should pick higher of 2");
     assert(nr != 3 || mid == hi-1, "should pick middle of 3");
     Node *test_val = _gvn.intcon(mid->lo());
     if (mid->is_singleton()) {
       IfNode *iff_ne = jump_if_fork_int(key_val, test_val, BoolTest::ne);
       jump_if_false_fork(iff_ne, mid->dest(), mid->table_index());
       // Special Case:  If there are exactly three ranges, and the high
       // and low range each go to the same place, omit the "gt" test,
       // since it will not discriminate anything.
       bool eq_test_only = (hi == lo+2 && hi->dest() == lo->dest());
       if (eq_test_only) {
         assert(mid == hi-1, "");
       }
       // if there is a higher range, test for it and process it:
       if (mid < hi && !eq_test_only) {
         // two comparisons of same values--should enable 1 test for 2 branches
         // Use BoolTest::le instead of BoolTest::gt
         IfNode *iff_le  = jump_if_fork_int(key_val, test_val, BoolTest::le);
         Node   *iftrue  = _gvn.transform( new (C) IfTrueNode(iff_le) );
         Node   *iffalse = _gvn.transform( new (C) IfFalseNode(iff_le) );
         { PreserveJVMState pjvms(this);
           set_control(iffalse);
           jump_switch_ranges(key_val, mid+1, hi, switch_depth+1);
         }
         set_control(iftrue);
       }
     } else {
       // mid is a range, not a singleton, so treat mid..hi as a unit
       IfNode *iff_ge = jump_if_fork_int(key_val, test_val, BoolTest::ge);
       // if there is a higher range, test for it and process it:
       if (mid == hi) {
         jump_if_true_fork(iff_ge, mid->dest(), mid->table_index());
       } else {
         Node *iftrue  = _gvn.transform( new (C) IfTrueNode(iff_ge) );
         Node *iffalse = _gvn.transform( new (C) IfFalseNode(iff_ge) );
         { PreserveJVMState pjvms(this);
           set_control(iftrue);
           jump_switch_ranges(key_val, mid, hi, switch_depth+1);
         }
         set_control(iffalse);
       }
     }
     // in any case, process the lower range
     jump_switch_ranges(key_val, lo, mid-1, switch_depth+1);
   }
   // Decrease pred_count for each successor after all is done.
   if (switch_depth == 0) {
     int unique_successors = switch_block->num_successors();
     for (int i = 0; i < unique_successors; i++) {
       Block* target = switch_block->successor_at(i);
       // Throw away the pre-allocated path for each unique successor.
       target->next_path_num();
     }
   }
 #ifndef PRODUCT
   _max_switch_depth = MAX2(switch_depth, _max_switch_depth);
   if (TraceOptoParse && Verbose && WizardMode && switch_depth == 0) {
     SwitchRange* r;
     int nsing = 0;
     for( r = lo; r <= hi; r++ ) {
       if( r->is_singleton() )  nsing++;
     }
     tty->print(">>> ");
     _method->print_short_name();
     tty->print_cr(" switch decision tree");
     tty->print_cr("    %d ranges (%d singletons), max_depth=%d, est_depth=%d",
                   hi-lo+1, nsing, _max_switch_depth, _est_switch_depth);
     if (_max_switch_depth > _est_switch_depth) {
       tty->print_cr("******** BAD SWITCH DEPTH ********");
     }
     tty->print("   ");
     for( r = lo; r <= hi; r++ ) {
       r->print(env());
     }
     tty->print_cr("");
   }
 #endif
 }
 void Parse::modf() {
   Node *f2 = pop();
   Node *f1 = pop();
   Node* c = make_runtime_call(RC_LEAF, OptoRuntime::modf_Type(),
                               CAST_FROM_FN_PTR(address, SharedRuntime::frem),
                               "frem", NULL, //no memory effects
                               f1, f2);
   Node* res = _gvn.transform(new (C) ProjNode(c, TypeFunc::Parms + 0));
   push(res);
 }
 void Parse::modd() {
   Node *d2 = pop_pair();
   Node *d1 = pop_pair();
   Node* c = make_runtime_call(RC_LEAF, OptoRuntime::Math_DD_D_Type(),
                               CAST_FROM_FN_PTR(address, SharedRuntime::drem),
                               "drem", NULL, //no memory effects
                               d1, top(), d2, top());
   Node* res_d   = _gvn.transform(new (C) ProjNode(c, TypeFunc::Parms + 0));
 #ifdef ASSERT
   Node* res_top = _gvn.transform(new (C) ProjNode(c, TypeFunc::Parms + 1));
   assert(res_top == top(), "second value must be top");
 #endif
   push_pair(res_d);
 }
 void Parse::l2f() {
   Node* f2 = pop();
   Node* f1 = pop();
   Node* c = make_runtime_call(RC_LEAF, OptoRuntime::l2f_Type(),
                               CAST_FROM_FN_PTR(address, SharedRuntime::l2f),
                               "l2f", NULL, //no memory effects
                               f1, f2);
   Node* res = _gvn.transform(new (C) ProjNode(c, TypeFunc::Parms + 0));
   push(res);
 }
 void Parse::do_irem() {
   // Must keep both values on the expression-stack during null-check
   zero_check_int(peek());
   // Compile-time detect of null-exception?
   if (stopped())  return;
   Node* b = pop();
   Node* a = pop();
   const Type *t = _gvn.type(b);
   if (t != Type::TOP) {
     const TypeInt *ti = t->is_int();
     if (ti->is_con()) {
       int divisor = ti->get_con();
       // check for positive power of 2
       if (divisor > 0 &&
           (divisor & ~(divisor-1)) == divisor) {
         // yes !
         Node *mask = _gvn.intcon((divisor - 1));
         // Sigh, must handle negative dividends
         Node *zero = _gvn.intcon(0);
         IfNode *ifff = jump_if_fork_int(a, zero, BoolTest::lt);
         Node *iff = _gvn.transform( new (C) IfFalseNode(ifff) );
         Node *ift = _gvn.transform( new (C) IfTrueNode (ifff) );
         Node *reg = jump_if_join(ift, iff);
         Node *phi = PhiNode::make(reg, NULL, TypeInt::INT);
         // Negative path; negate/and/negate
         Node *neg = _gvn.transform( new (C) SubINode(zero, a) );
         Node *andn= _gvn.transform( new (C) AndINode(neg, mask) );
         Node *negn= _gvn.transform( new (C) SubINode(zero, andn) );
         phi->init_req(1, negn);
         // Fast positive case
         Node *andx = _gvn.transform( new (C) AndINode(a, mask) );
         phi->init_req(2, andx);
         // Push the merge
         push( _gvn.transform(phi) );
         return;
       }
     }
   }
   // Default case
   push( _gvn.transform( new (C) ModINode(control(),a,b) ) );
 }
 // Handle jsr and jsr_w bytecode
 void Parse::do_jsr() {
   assert(bc() == Bytecodes::_jsr || bc() == Bytecodes::_jsr_w, "wrong bytecode");
   // Store information about current state, tagged with new _jsr_bci
   int return_bci = iter().next_bci();
   int jsr_bci    = (bc() == Bytecodes::_jsr) ? iter().get_dest() : iter().get_far_dest();
   // Update method data
   profile_taken_branch(jsr_bci);
   // The way we do things now, there is only one successor block
   // for the jsr, because the target code is cloned by ciTypeFlow.
   Block* target = successor_for_bci(jsr_bci);
   // What got pushed?
   const Type* ret_addr = target->peek();
   assert(ret_addr->singleton(), "must be a constant (cloned jsr body)");
   // Effect on jsr on stack
   push(_gvn.makecon(ret_addr));
   // Flow to the jsr.
   merge(jsr_bci);
 }
 // Handle ret bytecode
 void Parse::do_ret() {
   // Find to whom we return.
   assert(block()->num_successors() == 1, "a ret can only go one place now");
   Block* target = block()->successor_at(0);
   assert(!target->is_ready(), "our arrival must be expected");
   profile_ret(target->flow()->start());
   int pnum = target->next_path_num();
   merge_common(target, pnum);
 }
 //--------------------------dynamic_branch_prediction--------------------------
 // Try to gather dynamic branch prediction behavior.  Return a probability
 // of the branch being taken and set the "cnt" field.  Returns a -1.0
 // if we need to use static prediction for some reason.
 float Parse::dynamic_branch_prediction(float &cnt) {
   ResourceMark rm;
   cnt  = COUNT_UNKNOWN;
   // Use MethodData information if it is available
   // FIXME: free the ProfileData structure
   ciMethodData* methodData = method()->method_data();
   if (!methodData->is_mature())  return PROB_UNKNOWN;
   ciProfileData* data = methodData->bci_to_data(bci());
   if (!data->is_JumpData())  return PROB_UNKNOWN;
   // get taken and not taken values
   int     taken = data->as_JumpData()->taken();
   int not_taken = 0;
   if (data->is_BranchData()) {
     not_taken = data->as_BranchData()->not_taken();
   }
   // scale the counts to be commensurate with invocation counts:
   taken = method()->scale_count(taken);
   not_taken = method()->scale_count(not_taken);
   // Give up if too few (or too many, in which case the sum will overflow) counts to be meaningful.
   // We also check that individual counters are positive first, overwise the sum can become positive.
   if (taken < 0 || not_taken < 0 || taken + not_taken < 40) {
     if (C->log() != NULL) {
       C->log()->elem("branch target_bci='%d' taken='%d' not_taken='%d'", iter().get_dest(), taken, not_taken);
     }
     return PROB_UNKNOWN;
   }
   // Compute frequency that we arrive here
   float sum = taken + not_taken;
   // Adjust, if this block is a cloned private block but the
   // Jump counts are shared.  Taken the private counts for
   // just this path instead of the shared counts.
   if( block()->count() > 0 )
     sum = block()->count();
   cnt = sum / FreqCountInvocations;
   // Pin probability to sane limits
   float prob;
   if( !taken )
     prob = (0+PROB_MIN) / 2;
   else if( !not_taken )
     prob = (1+PROB_MAX) / 2;
   else {                         // Compute probability of true path
     prob = (float)taken / (float)(taken + not_taken);
     if (prob > PROB_MAX)  prob = PROB_MAX;
     if (prob < PROB_MIN)   prob = PROB_MIN;
   }
   assert((cnt > 0.0f) && (prob > 0.0f),
          "Bad frequency assignment in if");
   if (C->log() != NULL) {
     const char* prob_str = NULL;
     if (prob >= PROB_MAX)  prob_str = (prob == PROB_MAX) ? "max" : "always";
     if (prob <= PROB_MIN)  prob_str = (prob == PROB_MIN) ? "min" : "never";
     char prob_str_buf[30];
     if (prob_str == NULL) {
       sprintf(prob_str_buf, "%g", prob);
       prob_str = prob_str_buf;
     }
     C->log()->elem("branch target_bci='%d' taken='%d' not_taken='%d' cnt='%g' prob='%s'",
                    iter().get_dest(), taken, not_taken, cnt, prob_str);
   }
   return prob;
 }
 //-----------------------------branch_prediction-------------------------------
 float Parse::branch_prediction(float& cnt,
                                BoolTest::mask btest,
                                int target_bci) {
   float prob = dynamic_branch_prediction(cnt);
   // If prob is unknown, switch to static prediction
   if (prob != PROB_UNKNOWN)  return prob;
   prob = PROB_FAIR;                   // Set default value
   if (btest == BoolTest::eq)          // Exactly equal test?
     prob = PROB_STATIC_INFREQUENT;    // Assume its relatively infrequent
   else if (btest == BoolTest::ne)
     prob = PROB_STATIC_FREQUENT;      // Assume its relatively frequent
   // If this is a conditional test guarding a backwards branch,
   // assume its a loop-back edge.  Make it a likely taken branch.
   if (target_bci < bci()) {
     if (is_osr_parse()) {    // Could be a hot OSR'd loop; force deopt
       // Since it's an OSR, we probably have profile data, but since
       // branch_prediction returned PROB_UNKNOWN, the counts are too small.
       // Let's make a special check here for completely zero counts.
       ciMethodData* methodData = method()->method_data();
       if (!methodData->is_empty()) {
         ciProfileData* data = methodData->bci_to_data(bci());
         // Only stop for truly zero counts, which mean an unknown part
         // of the OSR-ed method, and we want to deopt to gather more stats.
         // If you have ANY counts, then this loop is simply 'cold' relative
         // to the OSR loop.
         if (data->as_BranchData()->taken() +
             data->as_BranchData()->not_taken() == 0 ) {
           // This is the only way to return PROB_UNKNOWN:
           return PROB_UNKNOWN;
         }
       }
     }
     prob = PROB_STATIC_FREQUENT;     // Likely to take backwards branch
   }
   assert(prob != PROB_UNKNOWN, "must have some guess at this point");
   return prob;
 }
 // The magic constants are chosen so as to match the output of
 // branch_prediction() when the profile reports a zero taken count.
 // It is important to distinguish zero counts unambiguously, because
 // some branches (e.g., _213_javac.Assembler.eliminate) validly produce
 // very small but nonzero probabilities, which if confused with zero
 // counts would keep the program recompiling indefinitely.
 bool Parse::seems_never_taken(float prob) {
   return prob < PROB_MIN;
 }
 // True if the comparison seems to be the kind that will not change its
 // statistics from true to false.  See comments in adjust_map_after_if.
 // This question is only asked along paths which are already
 // classifed as untaken (by seems_never_taken), so really,
 // if a path is never taken, its controlling comparison is
 // already acting in a stable fashion.  If the comparison
 // seems stable, we will put an expensive uncommon trap
 // on the untaken path.  To be conservative, and to allow
 // partially executed counted loops to be compiled fully,
 // we will plant uncommon traps only after pointer comparisons.
 bool Parse::seems_stable_comparison(BoolTest::mask btest, Node* cmp) {
   for (int depth = 4; depth > 0; depth--) {
     // The following switch can find CmpP here over half the time for
     // dynamic language code rich with type tests.
     // Code using counted loops or array manipulations (typical
     // of benchmarks) will have many (>80%) CmpI instructions.
     switch (cmp->Opcode()) {
     case Op_CmpP:
       // A never-taken null check looks like CmpP/BoolTest::eq.
       // These certainly should be closed off as uncommon traps.
       if (btest == BoolTest::eq)
         return true;
       // A never-failed type check looks like CmpP/BoolTest::ne.
       // Let's put traps on those, too, so that we don't have to compile
       // unused paths with indeterminate dynamic type information.
       if (ProfileDynamicTypes)
         return true;
       return false;
     case Op_CmpI:
       // A small minority (< 10%) of CmpP are masked as CmpI,
       // as if by boolean conversion ((p == q? 1: 0) != 0).
       // Detect that here, even if it hasn't optimized away yet.
       // Specifically, this covers the 'instanceof' operator.
       if (btest == BoolTest::ne || btest == BoolTest::eq) {
         if (_gvn.type(cmp->in(2))->singleton() &&
             cmp->in(1)->is_Phi()) {
           PhiNode* phi = cmp->in(1)->as_Phi();
           int true_path = phi->is_diamond_phi();
           if (true_path > 0 &&
               _gvn.type(phi->in(1))->singleton() &&
               _gvn.type(phi->in(2))->singleton()) {
             // phi->region->if_proj->ifnode->bool->cmp
             BoolNode* bol = phi->in(0)->in(1)->in(0)->in(1)->as_Bool();
             btest = bol->_test._test;
             cmp = bol->in(1);
             continue;
           }
         }
       }
       return false;
     }
   }
   return false;
 }
 //-------------------------------repush_if_args--------------------------------
 // Push arguments of an "if" bytecode back onto the stack by adjusting _sp.
 inline int Parse::repush_if_args() {
 #ifndef PRODUCT
   if (PrintOpto && WizardMode) {
     tty->print("defending against excessive implicit null exceptions on %s @%d in ",
                Bytecodes::name(iter().cur_bc()), iter().cur_bci());
     method()->print_name(); tty->cr();
   }
 #endif
   int bc_depth = - Bytecodes::depth(iter().cur_bc());
   assert(bc_depth == 1 || bc_depth == 2, "only two kinds of branches");
   DEBUG_ONLY(sync_jvms());   // argument(n) requires a synced jvms
   assert(argument(0) != NULL, "must exist");
   assert(bc_depth == 1 || argument(1) != NULL, "two must exist");
   inc_sp(bc_depth);
   return bc_depth;
 }
 //----------------------------------do_ifnull----------------------------------
 void Parse::do_ifnull(BoolTest::mask btest, Node *c) {
   int target_bci = iter().get_dest();
   Block* branch_block = successor_for_bci(target_bci);
   Block* next_block   = successor_for_bci(iter().next_bci());
   float cnt;
   float prob = branch_prediction(cnt, btest, target_bci);
   if (prob == PROB_UNKNOWN) {
     // (An earlier version of do_ifnull omitted this trap for OSR methods.)
 #ifndef PRODUCT
     if (PrintOpto && Verbose)
       tty->print_cr("Never-taken edge stops compilation at bci %d",bci());
 #endif
     repush_if_args(); // to gather stats on loop
     // We need to mark this branch as taken so that if we recompile we will
     // see that it is possible. In the tiered system the interpreter doesn't
     // do profiling and by the time we get to the lower tier from the interpreter
     // the path may be cold again. Make sure it doesn't look untaken
     profile_taken_branch(target_bci, !ProfileInterpreter);
     uncommon_trap(Deoptimization::Reason_unreached,
                   Deoptimization::Action_reinterpret,
                   NULL, "cold");
     if (EliminateAutoBox) {
       // Mark the successor blocks as parsed
       branch_block->next_path_num();
       next_block->next_path_num();
     }
     return;
   }
   explicit_null_checks_inserted++;
   // Generate real control flow
   Node   *tst = _gvn.transform( new (C) BoolNode( c, btest ) );
   // Sanity check the probability value
   assert(prob > 0.0f,"Bad probability in Parser");
  // Need xform to put node in hash table
   IfNode *iff = create_and_xform_if( control(), tst, prob, cnt );
   assert(iff->_prob > 0.0f,"Optimizer made bad probability in parser");
   // True branch
   { PreserveJVMState pjvms(this);
     Node* iftrue  = _gvn.transform( new (C) IfTrueNode (iff) );
     set_control(iftrue);
     if (stopped()) {            // Path is dead?
       explicit_null_checks_elided++;
       if (EliminateAutoBox) {
         // Mark the successor block as parsed
         branch_block->next_path_num();
       }
     } else {                    // Path is live.
       // Update method data
       profile_taken_branch(target_bci);
       adjust_map_after_if(btest, c, prob, branch_block, next_block);
       if (!stopped()) {
         merge(target_bci);
       }
     }
   }
   // False branch
   Node* iffalse = _gvn.transform( new (C) IfFalseNode(iff) );
   set_control(iffalse);
   if (stopped()) {              // Path is dead?
     explicit_null_checks_elided++;
     if (EliminateAutoBox) {
       // Mark the successor block as parsed
       next_block->next_path_num();
     }
   } else  {                     // Path is live.
     // Update method data
     profile_not_taken_branch();
     adjust_map_after_if(BoolTest(btest).negate(), c, 1.0-prob,
                         next_block, branch_block);
   }
 }
 //------------------------------------do_if------------------------------------
 void Parse::do_if(BoolTest::mask btest, Node* c) {
   int target_bci = iter().get_dest();
   Block* branch_block = successor_for_bci(target_bci);
   Block* next_block   = successor_for_bci(iter().next_bci());
   float cnt;
   float prob = branch_prediction(cnt, btest, target_bci);
   float untaken_prob = 1.0 - prob;
   if (prob == PROB_UNKNOWN) {
 #ifndef PRODUCT
     if (PrintOpto && Verbose)
       tty->print_cr("Never-taken edge stops compilation at bci %d",bci());
 #endif
     repush_if_args(); // to gather stats on loop
     // We need to mark this branch as taken so that if we recompile we will
     // see that it is possible. In the tiered system the interpreter doesn't
     // do profiling and by the time we get to the lower tier from the interpreter
     // the path may be cold again. Make sure it doesn't look untaken
     profile_taken_branch(target_bci, !ProfileInterpreter);
     uncommon_trap(Deoptimization::Reason_unreached,
                   Deoptimization::Action_reinterpret,
                   NULL, "cold");
     if (EliminateAutoBox) {
       // Mark the successor blocks as parsed
       branch_block->next_path_num();
       next_block->next_path_num();
     }
     return;
   }
   // Sanity check the probability value
   assert(0.0f < prob && prob < 1.0f,"Bad probability in Parser");
   bool taken_if_true = true;
   // Convert BoolTest to canonical form:
   if (!BoolTest(btest).is_canonical()) {
     btest         = BoolTest(btest).negate();
     taken_if_true = false;
     // prob is NOT updated here; it remains the probability of the taken
     // path (as opposed to the prob of the path guarded by an 'IfTrueNode').
   }
   assert(btest != BoolTest::eq, "!= is the only canonical exact test");
   Node* tst0 = new (C) BoolNode(c, btest);
   Node* tst = _gvn.transform(tst0);
   BoolTest::mask taken_btest   = BoolTest::illegal;
   BoolTest::mask untaken_btest = BoolTest::illegal;
   if (tst->is_Bool()) {
     // Refresh c from the transformed bool node, since it may be
     // simpler than the original c.  Also re-canonicalize btest.
     // This wins when (Bool ne (Conv2B p) 0) => (Bool ne (CmpP p NULL)).
     // That can arise from statements like: if (x instanceof C) ...
     if (tst != tst0) {
       // Canonicalize one more time since transform can change it.
       btest = tst->as_Bool()->_test._test;
       if (!BoolTest(btest).is_canonical()) {
         // Reverse edges one more time...
         tst   = _gvn.transform( tst->as_Bool()->negate(&_gvn) );
         btest = tst->as_Bool()->_test._test;
         assert(BoolTest(btest).is_canonical(), "sanity");
         taken_if_true = !taken_if_true;
       }
       c = tst->in(1);
     }
     BoolTest::mask neg_btest = BoolTest(btest).negate();
     taken_btest   = taken_if_true ?     btest : neg_btest;
     untaken_btest = taken_if_true ? neg_btest :     btest;
   }
   // Generate real control flow
   float true_prob = (taken_if_true ? prob : untaken_prob);
   IfNode* iff = create_and_map_if(control(), tst, true_prob, cnt);
   assert(iff->_prob > 0.0f,"Optimizer made bad probability in parser");
   Node* taken_branch   = new (C) IfTrueNode(iff);
   Node* untaken_branch = new (C) IfFalseNode(iff);
   if (!taken_if_true) {  // Finish conversion to canonical form
     Node* tmp      = taken_branch;
     taken_branch   = untaken_branch;
     untaken_branch = tmp;
   }
   // Branch is taken:
   { PreserveJVMState pjvms(this);
     taken_branch = _gvn.transform(taken_branch);
     set_control(taken_branch);
     if (stopped()) {
       if (EliminateAutoBox) {
         // Mark the successor block as parsed
         branch_block->next_path_num();
       }
     } else {
       // Update method data
       profile_taken_branch(target_bci);
       adjust_map_after_if(taken_btest, c, prob, branch_block, next_block);
       if (!stopped()) {
         merge(target_bci);
       }
     }
   }
   untaken_branch = _gvn.transform(untaken_branch);
   set_control(untaken_branch);
   // Branch not taken.
   if (stopped()) {
     if (EliminateAutoBox) {
       // Mark the successor block as parsed
       next_block->next_path_num();
     }
   } else {
     // Update method data
     profile_not_taken_branch();
     adjust_map_after_if(untaken_btest, c, untaken_prob,
                         next_block, branch_block);
   }
 }
 //----------------------------adjust_map_after_if------------------------------
 // Adjust the JVM state to reflect the result of taking this path.
 // Basically, it means inspecting the CmpNode controlling this
 // branch, seeing how it constrains a tested value, and then
 // deciding if it's worth our while to encode this constraint
 // as graph nodes in the current abstract interpretation map.
 void Parse::adjust_map_after_if(BoolTest::mask btest, Node* c, float prob,
                                 Block* path, Block* other_path) {
   if (stopped() || !c->is_Cmp() || btest == BoolTest::illegal)
     return;                             // nothing to do
   bool is_fallthrough = (path == successor_for_bci(iter().next_bci()));
   if (seems_never_taken(prob) && seems_stable_comparison(btest, c)) {
     // If this might possibly turn into an implicit null check,
     // and the null has never yet been seen, we need to generate
     // an uncommon trap, so as to recompile instead of suffering
     // with very slow branches.  (We'll get the slow branches if
     // the program ever changes phase and starts seeing nulls here.)
     //
     // We do not inspect for a null constant, since a node may
     // optimize to 'null' later on.
     //
     // Null checks, and other tests which expect inequality,
     // show btest == BoolTest::eq along the non-taken branch.
     // On the other hand, type tests, must-be-null tests,
     // and other tests which expect pointer equality,
     // show btest == BoolTest::ne along the non-taken branch.
     // We prune both types of branches if they look unused.
     repush_if_args();
     // We need to mark this branch as taken so that if we recompile we will
     // see that it is possible. In the tiered system the interpreter doesn't
     // do profiling and by the time we get to the lower tier from the interpreter
     // the path may be cold again. Make sure it doesn't look untaken
     if (is_fallthrough) {
       profile_not_taken_branch(!ProfileInterpreter);
     } else {
       profile_taken_branch(iter().get_dest(), !ProfileInterpreter);
     }
     uncommon_trap(Deoptimization::Reason_unreached,
                   Deoptimization::Action_reinterpret,
                   NULL,
                   (is_fallthrough ? "taken always" : "taken never"));
     return;
   }
   Node* val = c->in(1);
   Node* con = c->in(2);
   const Type* tcon = _gvn.type(con);
   const Type* tval = _gvn.type(val);
   bool have_con = tcon->singleton();
   if (tval->singleton()) {
     if (!have_con) {
       // Swap, so constant is in con.
       con  = val;
       tcon = tval;
       val  = c->in(2);
       tval = _gvn.type(val);
       btest = BoolTest(btest).commute();
       have_con = true;
     } else {
       // Do we have two constants?  Then leave well enough alone.
       have_con = false;
     }
   }
   if (!have_con)                        // remaining adjustments need a con
     return;
   sharpen_type_after_if(btest, con, tcon, val, tval);
 }
 static Node* extract_obj_from_klass_load(PhaseGVN* gvn, Node* n) {
   Node* ldk;
   if (n->is_DecodeNKlass()) {
     if (n->in(1)->Opcode() != Op_LoadNKlass) {
       return NULL;
     } else {
       ldk = n->in(1);
     }
   } else if (n->Opcode() != Op_LoadKlass) {
     return NULL;
   } else {
     ldk = n;
   }
   assert(ldk != NULL && ldk->is_Load(), "should have found a LoadKlass or LoadNKlass node");
   Node* adr = ldk->in(MemNode::Address);
   intptr_t off = 0;
   Node* obj = AddPNode::Ideal_base_and_offset(adr, gvn, off);
   if (obj == NULL || off != oopDesc::klass_offset_in_bytes()) // loading oopDesc::_klass?
     return NULL;
   const TypePtr* tp = gvn->type(obj)->is_ptr();
   if (tp == NULL || !(tp->isa_instptr() || tp->isa_aryptr())) // is obj a Java object ptr?
     return NULL;
   return obj;
 }
 void Parse::sharpen_type_after_if(BoolTest::mask btest,
                                   Node* con, const Type* tcon,
                                   Node* val, const Type* tval) {
   // Look for opportunities to sharpen the type of a node
   // whose klass is compared with a constant klass.
   if (btest == BoolTest::eq && tcon->isa_klassptr()) {
     Node* obj = extract_obj_from_klass_load(&_gvn, val);
     const TypeOopPtr* con_type = tcon->isa_klassptr()->as_instance_type();
     if (obj != NULL && (con_type->isa_instptr() || con_type->isa_aryptr())) {
        // Found:
        //   Bool(CmpP(LoadKlass(obj._klass), ConP(Foo.klass)), [eq])
        // or the narrowOop equivalent.
        const Type* obj_type = _gvn.type(obj);
        const TypeOopPtr* tboth = obj_type->join(con_type)->isa_oopptr();
        if (tboth != NULL && tboth->klass_is_exact() && tboth != obj_type &&
            tboth->higher_equal(obj_type)) {
           // obj has to be of the exact type Foo if the CmpP succeeds.
           int obj_in_map = map()->find_edge(obj);
           JVMState* jvms = this->jvms();
           if (obj_in_map >= 0 &&
               (jvms->is_loc(obj_in_map) || jvms->is_stk(obj_in_map))) {
             TypeNode* ccast = new (C) CheckCastPPNode(control(), obj, tboth);
             const Type* tcc = ccast->as_Type()->type();
             assert(tcc != obj_type && tcc->higher_equal(obj_type), "must improve");
             // Delay transform() call to allow recovery of pre-cast value
             // at the control merge.
             _gvn.set_type_bottom(ccast);
             record_for_igvn(ccast);
             // Here's the payoff.
             replace_in_map(obj, ccast);
           }
        }
     }
   }
   int val_in_map = map()->find_edge(val);
   if (val_in_map < 0)  return;          // replace_in_map would be useless
   {
     JVMState* jvms = this->jvms();
     if (!(jvms->is_loc(val_in_map) ||
           jvms->is_stk(val_in_map)))
       return;                           // again, it would be useless
   }
   // Check for a comparison to a constant, and "know" that the compared
   // value is constrained on this path.
   assert(tcon->singleton(), "");
   ConstraintCastNode* ccast = NULL;
   Node* cast = NULL;
   switch (btest) {
   case BoolTest::eq:                    // Constant test?
     {
       const Type* tboth = tcon->join(tval);
       if (tboth == tval)  break;        // Nothing to gain.
       if (tcon->isa_int()) {
         ccast = new (C) CastIINode(val, tboth);
       } else if (tcon == TypePtr::NULL_PTR) {
         // Cast to null, but keep the pointer identity temporarily live.
         ccast = new (C) CastPPNode(val, tboth);
       } else {
         const TypeF* tf = tcon->isa_float_constant();
         const TypeD* td = tcon->isa_double_constant();
         // Exclude tests vs float/double 0 as these could be
         // either +0 or -0.  Just because you are equal to +0
         // doesn't mean you ARE +0!
         // Note, following code also replaces Long and Oop values.
         if ((!tf || tf->_f != 0.0) &&
             (!td || td->_d != 0.0))
           cast = con;                   // Replace non-constant val by con.
       }
     }
     break;
   case BoolTest::ne:
     if (tcon == TypePtr::NULL_PTR) {
       cast = cast_not_null(val, false);
     }
     break;
   default:
     // (At this point we could record int range types with CastII.)
     break;
   }
   if (ccast != NULL) {
     const Type* tcc = ccast->as_Type()->type();
     assert(tcc != tval && tcc->higher_equal(tval), "must improve");
     // Delay transform() call to allow recovery of pre-cast value
     // at the control merge.
     ccast->set_req(0, control());
     _gvn.set_type_bottom(ccast);
     record_for_igvn(ccast);
     cast = ccast;
   }
   if (cast != NULL) {                   // Here's the payoff.
     replace_in_map(val, cast);
   }
 }
 //------------------------------do_one_bytecode--------------------------------
 // Parse this bytecode, and alter the Parsers JVM->Node mapping
 void Parse::do_one_bytecode() {
   Node *a, *b, *c, *d;          // Handy temps
   BoolTest::mask btest;
   int i;
   assert(!has_exceptions(), "bytecode entry state must be clear of throws");
   if (C->check_node_count(NodeLimitFudgeFactor * 5,
                           "out of nodes parsing method")) {
     return;
   }
 #ifdef ASSERT
   // for setting breakpoints
   if (TraceOptoParse) {
     tty->print(" @");
     dump_bci(bci());
   }
 #endif
   switch (bc()) {
   case Bytecodes::_nop:
     // do nothing
     break;
   case Bytecodes::_lconst_0:
     push_pair(longcon(0));
     break;
   case Bytecodes::_lconst_1:
     push_pair(longcon(1));
     break;
   case Bytecodes::_fconst_0:
     push(zerocon(T_FLOAT));
     break;
   case Bytecodes::_fconst_1:
     push(makecon(TypeF::ONE));
     break;
   case Bytecodes::_fconst_2:
     push(makecon(TypeF::make(2.0f)));
     break;
   case Bytecodes::_dconst_0:
     push_pair(zerocon(T_DOUBLE));
     break;
   case Bytecodes::_dconst_1:
     push_pair(makecon(TypeD::ONE));
     break;
   case Bytecodes::_iconst_m1:push(intcon(-1)); break;
   case Bytecodes::_iconst_0: push(intcon( 0)); break;
   case Bytecodes::_iconst_1: push(intcon( 1)); break;
   case Bytecodes::_iconst_2: push(intcon( 2)); break;
   case Bytecodes::_iconst_3: push(intcon( 3)); break;
   case Bytecodes::_iconst_4: push(intcon( 4)); break;
   case Bytecodes::_iconst_5: push(intcon( 5)); break;
   case Bytecodes::_bipush:   push(intcon(iter().get_constant_u1())); break;
   case Bytecodes::_sipush:   push(intcon(iter().get_constant_u2())); break;
   case Bytecodes::_aconst_null: push(null());  break;
   case Bytecodes::_ldc:
   case Bytecodes::_ldc_w:
   case Bytecodes::_ldc2_w:
     // If the constant is unresolved, run this BC once in the interpreter.
     {
       ciConstant constant = iter().get_constant();
       if (constant.basic_type() == T_OBJECT &&
           !constant.as_object()->is_loaded()) {
         int index = iter().get_constant_pool_index();
         constantTag tag = iter().get_constant_pool_tag(index);
         uncommon_trap(Deoptimization::make_trap_request
                       (Deoptimization::Reason_unloaded,
                        Deoptimization::Action_reinterpret,
                        index),
                       NULL, tag.internal_name());
         break;
       }
       assert(constant.basic_type() != T_OBJECT || constant.as_object()->is_instance(),
              "must be java_mirror of klass");
       bool pushed = push_constant(constant, true);
       guarantee(pushed, "must be possible to push this constant");
     }
     break;
   case Bytecodes::_aload_0:
     push( local(0) );
     break;
   case Bytecodes::_aload_1:
     push( local(1) );
     break;
   case Bytecodes::_aload_2:
     push( local(2) );
     break;
   case Bytecodes::_aload_3:
     push( local(3) );
     break;
   case Bytecodes::_aload:
     push( local(iter().get_index()) );
     break;
   case Bytecodes::_fload_0:
   case Bytecodes::_iload_0:
     push( local(0) );
     break;
   case Bytecodes::_fload_1:
   case Bytecodes::_iload_1:
     push( local(1) );
     break;
   case Bytecodes::_fload_2:
   case Bytecodes::_iload_2:
     push( local(2) );
     break;
   case Bytecodes::_fload_3:
   case Bytecodes::_iload_3:
     push( local(3) );
     break;
   case Bytecodes::_fload:
   case Bytecodes::_iload:
     push( local(iter().get_index()) );
     break;
   case Bytecodes::_lload_0:
     push_pair_local( 0 );
     break;
   case Bytecodes::_lload_1:
     push_pair_local( 1 );
     break;
   case Bytecodes::_lload_2:
     push_pair_local( 2 );
     break;
   case Bytecodes::_lload_3:
     push_pair_local( 3 );
     break;
   case Bytecodes::_lload:
     push_pair_local( iter().get_index() );
     break;
   case Bytecodes::_dload_0:
     push_pair_local(0);
     break;
   case Bytecodes::_dload_1:
     push_pair_local(1);
     break;
   case Bytecodes::_dload_2:
     push_pair_local(2);
     break;
   case Bytecodes::_dload_3:
     push_pair_local(3);
     break;
   case Bytecodes::_dload:
     push_pair_local(iter().get_index());
     break;
   case Bytecodes::_fstore_0:
   case Bytecodes::_istore_0:
   case Bytecodes::_astore_0:
     set_local( 0, pop() );
     break;
   case Bytecodes::_fstore_1:
   case Bytecodes::_istore_1:
   case Bytecodes::_astore_1:
     set_local( 1, pop() );
     break;
   case Bytecodes::_fstore_2:
   case Bytecodes::_istore_2:
   case Bytecodes::_astore_2:
     set_local( 2, pop() );
     break;
   case Bytecodes::_fstore_3:
   case Bytecodes::_istore_3:
   case Bytecodes::_astore_3:
     set_local( 3, pop() );
     break;
   case Bytecodes::_fstore:
   case Bytecodes::_istore:
   case Bytecodes::_astore:
     set_local( iter().get_index(), pop() );
     break;
   // long stores
   case Bytecodes::_lstore_0:
     set_pair_local( 0, pop_pair() );
     break;
   case Bytecodes::_lstore_1:
     set_pair_local( 1, pop_pair() );
     break;
   case Bytecodes::_lstore_2:
     set_pair_local( 2, pop_pair() );
     break;
   case Bytecodes::_lstore_3:
     set_pair_local( 3, pop_pair() );
     break;
   case Bytecodes::_lstore:
     set_pair_local( iter().get_index(), pop_pair() );
     break;
   // double stores
   case Bytecodes::_dstore_0:
     set_pair_local( 0, dstore_rounding(pop_pair()) );
     break;
   case Bytecodes::_dstore_1:
     set_pair_local( 1, dstore_rounding(pop_pair()) );
     break;
   case Bytecodes::_dstore_2:
     set_pair_local( 2, dstore_rounding(pop_pair()) );
     break;
   case Bytecodes::_dstore_3:
     set_pair_local( 3, dstore_rounding(pop_pair()) );
     break;
   case Bytecodes::_dstore:
     set_pair_local( iter().get_index(), dstore_rounding(pop_pair()) );
     break;
   case Bytecodes::_pop:  dec_sp(1);   break;
   case Bytecodes::_pop2: dec_sp(2);   break;
   case Bytecodes::_swap:
     a = pop();
     b = pop();
     push(a);
     push(b);
     break;
   case Bytecodes::_dup:
     a = pop();
     push(a);
     push(a);
     break;
   case Bytecodes::_dup_x1:
     a = pop();
     b = pop();
     push( a );
     push( b );
     push( a );
     break;
   case Bytecodes::_dup_x2:
     a = pop();
     b = pop();
     c = pop();
     push( a );
     push( c );
     push( b );
     push( a );
     break;
   case Bytecodes::_dup2:
     a = pop();
     b = pop();
     push( b );
     push( a );
     push( b );
     push( a );
     break;
   case Bytecodes::_dup2_x1:
     // before: .. c, b, a
     // after:  .. b, a, c, b, a
     // not tested
     a = pop();
     b = pop();
     c = pop();
     push( b );
     push( a );
     push( c );
     push( b );
     push( a );
     break;
   case Bytecodes::_dup2_x2:
     // before: .. d, c, b, a
     // after:  .. b, a, d, c, b, a
     // not tested
     a = pop();
     b = pop();
     c = pop();
     d = pop();
     push( b );
     push( a );
     push( d );
     push( c );
     push( b );
     push( a );
     break;
   case Bytecodes::_arraylength: {
     // Must do null-check with value on expression stack
     Node *ary = null_check(peek(), T_ARRAY);
     // Compile-time detect of null-exception?
     if (stopped())  return;
     a = pop();
     push(load_array_length(a));
     break;
   }
   case Bytecodes::_baload: array_load(T_BYTE);   break;
   case Bytecodes::_caload: array_load(T_CHAR);   break;
   case Bytecodes::_iaload: array_load(T_INT);    break;
   case Bytecodes::_saload: array_load(T_SHORT);  break;
   case Bytecodes::_faload: array_load(T_FLOAT);  break;
   case Bytecodes::_aaload: array_load(T_OBJECT); break;
   case Bytecodes::_laload: {
     a = array_addressing(T_LONG, 0);
     if (stopped())  return;     // guaranteed null or range check
     dec_sp(2);                  // Pop array and index
     push_pair(make_load(control(), a, TypeLong::LONG, T_LONG, TypeAryPtr::LONGS));
     break;
   }
   case Bytecodes::_daload: {
     a = array_addressing(T_DOUBLE, 0);
     if (stopped())  return;     // guaranteed null or range check
     dec_sp(2);                  // Pop array and index
     push_pair(make_load(control(), a, Type::DOUBLE, T_DOUBLE, TypeAryPtr::DOUBLES));
     break;
   }
   case Bytecodes::_bastore: array_store(T_BYTE);  break;
   case Bytecodes::_castore: array_store(T_CHAR);  break;
   case Bytecodes::_iastore: array_store(T_INT);   break;
   case Bytecodes::_sastore: array_store(T_SHORT); break;
   case Bytecodes::_fastore: array_store(T_FLOAT); break;
   case Bytecodes::_aastore: {
     d = array_addressing(T_OBJECT, 1);
     if (stopped())  return;     // guaranteed null or range check
     array_store_check();
     c = pop();                  // Oop to store
     b = pop();                  // index (already used)
     a = pop();                  // the array itself
     const TypeOopPtr* elemtype  = _gvn.type(a)->is_aryptr()->elem()->make_oopptr();
     const TypeAryPtr* adr_type = TypeAryPtr::OOPS;
     Node* store = store_oop_to_array(control(), a, d, adr_type, c, elemtype, T_OBJECT);
     break;
   }
   case Bytecodes::_lastore: {
     a = array_addressing(T_LONG, 2);
     if (stopped())  return;     // guaranteed null or range check
     c = pop_pair();
     dec_sp(2);                  // Pop array and index
     store_to_memory(control(), a, c, T_LONG, TypeAryPtr::LONGS);
     break;
   }
   case Bytecodes::_dastore: {
     a = array_addressing(T_DOUBLE, 2);
     if (stopped())  return;     // guaranteed null or range check
     c = pop_pair();
     dec_sp(2);                  // Pop array and index
     c = dstore_rounding(c);
     store_to_memory(control(), a, c, T_DOUBLE, TypeAryPtr::DOUBLES);
     break;
   }
   case Bytecodes::_getfield:
     do_getfield();
     break;
   case Bytecodes::_getstatic:
     do_getstatic();
     break;
   case Bytecodes::_putfield:
     do_putfield();
     break;
   case Bytecodes::_putstatic:
     do_putstatic();
     break;
   case Bytecodes::_irem:
     do_irem();
     break;
   case Bytecodes::_idiv:
     // Must keep both values on the expression-stack during null-check
     zero_check_int(peek());
     // Compile-time detect of null-exception?
     if (stopped())  return;
     b = pop();
     a = pop();
     push( _gvn.transform( new (C) DivINode(control(),a,b) ) );
     break;
   case Bytecodes::_imul:
     b = pop(); a = pop();
     push( _gvn.transform( new (C) MulINode(a,b) ) );
     break;
   case Bytecodes::_iadd:
     b = pop(); a = pop();
     push( _gvn.transform( new (C) AddINode(a,b) ) );
     break;
   case Bytecodes::_ineg:
     a = pop();
     push( _gvn.transform( new (C) SubINode(_gvn.intcon(0),a)) );
     break;
   case Bytecodes::_isub:
     b = pop(); a = pop();
     push( _gvn.transform( new (C) SubINode(a,b) ) );
     break;
   case Bytecodes::_iand:
     b = pop(); a = pop();
     push( _gvn.transform( new (C) AndINode(a,b) ) );
     break;
   case Bytecodes::_ior:
     b = pop(); a = pop();
     push( _gvn.transform( new (C) OrINode(a,b) ) );
     break;
   case Bytecodes::_ixor:
     b = pop(); a = pop();
     push( _gvn.transform( new (C) XorINode(a,b) ) );
     break;
   case Bytecodes::_ishl:
     b = pop(); a = pop();
     push( _gvn.transform( new (C) LShiftINode(a,b) ) );
     break;
   case Bytecodes::_ishr:
     b = pop(); a = pop();
     push( _gvn.transform( new (C) RShiftINode(a,b) ) );
     break;
   case Bytecodes::_iushr:
     b = pop(); a = pop();
     push( _gvn.transform( new (C) URShiftINode(a,b) ) );
     break;
   case Bytecodes::_fneg:
     a = pop();
     b = _gvn.transform(new (C) NegFNode (a));
     push(b);
     break;
   case Bytecodes::_fsub:
     b = pop();
     a = pop();
     c = _gvn.transform( new (C) SubFNode(a,b) );
     d = precision_rounding(c);
     push( d );
     break;
   case Bytecodes::_fadd:
     b = pop();
     a = pop();
     c = _gvn.transform( new (C) AddFNode(a,b) );
     d = precision_rounding(c);
     push( d );
     break;
   case Bytecodes::_fmul:
     b = pop();
     a = pop();
     c = _gvn.transform( new (C) MulFNode(a,b) );
     d = precision_rounding(c);
     push( d );
     break;
   case Bytecodes::_fdiv:
     b = pop();
     a = pop();
     c = _gvn.transform( new (C) DivFNode(0,a,b) );
     d = precision_rounding(c);
     push( d );
     break;
   case Bytecodes::_frem:
     if (Matcher::has_match_rule(Op_ModF)) {
       // Generate a ModF node.
       b = pop();
       a = pop();
       c = _gvn.transform( new (C) ModFNode(0,a,b) );
       d = precision_rounding(c);
       push( d );
     }
     else {
       // Generate a call.
       modf();
     }
     break;
   case Bytecodes::_fcmpl:
     b = pop();
     a = pop();
     c = _gvn.transform( new (C) CmpF3Node( a, b));
     push(c);
     break;
   case Bytecodes::_fcmpg:
     b = pop();
     a = pop();
     // Same as fcmpl but need to flip the unordered case.  Swap the inputs,
     // which negates the result sign except for unordered.  Flip the unordered
     // as well by using CmpF3 which implements unordered-lesser instead of
     // unordered-greater semantics.  Finally, commute the result bits.  Result
     // is same as using a CmpF3Greater except we did it with CmpF3 alone.
     c = _gvn.transform( new (C) CmpF3Node( b, a));
     c = _gvn.transform( new (C) SubINode(_gvn.intcon(0),c) );
     push(c);
     break;
   case Bytecodes::_f2i:
     a = pop();
     push(_gvn.transform(new (C) ConvF2INode(a)));
     break;
   case Bytecodes::_d2i:
     a = pop_pair();
     b = _gvn.transform(new (C) ConvD2INode(a));
     push( b );
     break;
   case Bytecodes::_f2d:
     a = pop();
     b = _gvn.transform( new (C) ConvF2DNode(a));
     push_pair( b );
     break;
   case Bytecodes::_d2f:
     a = pop_pair();
     b = _gvn.transform( new (C) ConvD2FNode(a));
     // This breaks _227_mtrt (speed & correctness) and _222_mpegaudio (speed)
     //b = _gvn.transform(new (C) RoundFloatNode(0, b) );
     push( b );
     break;
   case Bytecodes::_l2f:
     if (Matcher::convL2FSupported()) {
       a = pop_pair();
       b = _gvn.transform( new (C) ConvL2FNode(a));
       // For i486.ad, FILD doesn't restrict precision to 24 or 53 bits.
       // Rather than storing the result into an FP register then pushing
       // out to memory to round, the machine instruction that implements
       // ConvL2D is responsible for rounding.
       // c = precision_rounding(b);
       c = _gvn.transform(b);
       push(c);
     } else {
       l2f();
     }
     break;
   case Bytecodes::_l2d:
     a = pop_pair();
     b = _gvn.transform( new (C) ConvL2DNode(a));
     // For i486.ad, rounding is always necessary (see _l2f above).
     // c = dprecision_rounding(b);
     c = _gvn.transform(b);
     push_pair(c);
     break;
   case Bytecodes::_f2l:
     a = pop();
     b = _gvn.transform( new (C) ConvF2LNode(a));
     push_pair(b);
     break;
   case Bytecodes::_d2l:
     a = pop_pair();
     b = _gvn.transform( new (C) ConvD2LNode(a));
     push_pair(b);
     break;
   case Bytecodes::_dsub:
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) SubDNode(a,b) );
     d = dprecision_rounding(c);
     push_pair( d );
     break;
   case Bytecodes::_dadd:
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) AddDNode(a,b) );
     d = dprecision_rounding(c);
     push_pair( d );
     break;
   case Bytecodes::_dmul:
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) MulDNode(a,b) );
     d = dprecision_rounding(c);
     push_pair( d );
     break;
   case Bytecodes::_ddiv:
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) DivDNode(0,a,b) );
     d = dprecision_rounding(c);
     push_pair( d );
     break;
   case Bytecodes::_dneg:
     a = pop_pair();
     b = _gvn.transform(new (C) NegDNode (a));
     push_pair(b);
     break;
   case Bytecodes::_drem:
     if (Matcher::has_match_rule(Op_ModD)) {
       // Generate a ModD node.
       b = pop_pair();
       a = pop_pair();
       // a % b
       c = _gvn.transform( new (C) ModDNode(0,a,b) );
       d = dprecision_rounding(c);
       push_pair( d );
     }
     else {
       // Generate a call.
       modd();
     }
     break;
   case Bytecodes::_dcmpl:
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) CmpD3Node( a, b));
     push(c);
     break;
   case Bytecodes::_dcmpg:
     b = pop_pair();
     a = pop_pair();
     // Same as dcmpl but need to flip the unordered case.
     // Commute the inputs, which negates the result sign except for unordered.
     // Flip the unordered as well by using CmpD3 which implements
     // unordered-lesser instead of unordered-greater semantics.
     // Finally, negate the result bits.  Result is same as using a
     // CmpD3Greater except we did it with CmpD3 alone.
     c = _gvn.transform( new (C) CmpD3Node( b, a));
     c = _gvn.transform( new (C) SubINode(_gvn.intcon(0),c) );
     push(c);
     break;
     // Note for longs -> lo word is on TOS, hi word is on TOS - 1
   case Bytecodes::_land:
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) AndLNode(a,b) );
     push_pair(c);
     break;
   case Bytecodes::_lor:
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) OrLNode(a,b) );
     push_pair(c);
     break;
   case Bytecodes::_lxor:
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) XorLNode(a,b) );
     push_pair(c);
     break;
   case Bytecodes::_lshl:
     b = pop();                  // the shift count
     a = pop_pair();             // value to be shifted
     c = _gvn.transform( new (C) LShiftLNode(a,b) );
     push_pair(c);
     break;
   case Bytecodes::_lshr:
     b = pop();                  // the shift count
     a = pop_pair();             // value to be shifted
     c = _gvn.transform( new (C) RShiftLNode(a,b) );
     push_pair(c);
     break;
   case Bytecodes::_lushr:
     b = pop();                  // the shift count
     a = pop_pair();             // value to be shifted
     c = _gvn.transform( new (C) URShiftLNode(a,b) );
     push_pair(c);
     break;
   case Bytecodes::_lmul:
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) MulLNode(a,b) );
     push_pair(c);
     break;
   case Bytecodes::_lrem:
     // Must keep both values on the expression-stack during null-check
     assert(peek(0) == top(), "long word order");
     zero_check_long(peek(1));
     // Compile-time detect of null-exception?
     if (stopped())  return;
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) ModLNode(control(),a,b) );
     push_pair(c);
     break;
   case Bytecodes::_ldiv:
     // Must keep both values on the expression-stack during null-check
     assert(peek(0) == top(), "long word order");
     zero_check_long(peek(1));
     // Compile-time detect of null-exception?
     if (stopped())  return;
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) DivLNode(control(),a,b) );
     push_pair(c);
     break;
   case Bytecodes::_ladd:
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) AddLNode(a,b) );
     push_pair(c);
     break;
   case Bytecodes::_lsub:
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) SubLNode(a,b) );
     push_pair(c);
     break;
   case Bytecodes::_lcmp:
     // Safepoints are now inserted _before_ branches.  The long-compare
     // bytecode painfully produces a 3-way value (-1,0,+1) which requires a
     // slew of control flow.  These are usually followed by a CmpI vs zero and
     // a branch; this pattern then optimizes to the obvious long-compare and
     // branch.  However, if the branch is backwards there's a Safepoint
     // inserted.  The inserted Safepoint captures the JVM state at the
     // pre-branch point, i.e. it captures the 3-way value.  Thus if a
     // long-compare is used to control a loop the debug info will force
     // computation of the 3-way value, even though the generated code uses a
     // long-compare and branch.  We try to rectify the situation by inserting
     // a SafePoint here and have it dominate and kill the safepoint added at a
     // following backwards branch.  At this point the JVM state merely holds 2
     // longs but not the 3-way value.
     if( UseLoopSafepoints ) {
       switch( iter().next_bc() ) {
       case Bytecodes::_ifgt:
       case Bytecodes::_iflt:
       case Bytecodes::_ifge:
       case Bytecodes::_ifle:
       case Bytecodes::_ifne:
       case Bytecodes::_ifeq:
         // If this is a backwards branch in the bytecodes, add Safepoint
         maybe_add_safepoint(iter().next_get_dest());
       }
     }
     b = pop_pair();
     a = pop_pair();
     c = _gvn.transform( new (C) CmpL3Node( a, b ));
     push(c);
     break;
   case Bytecodes::_lneg:
     a = pop_pair();
     b = _gvn.transform( new (C) SubLNode(longcon(0),a));
     push_pair(b);
     break;
   case Bytecodes::_l2i:
     a = pop_pair();
     push( _gvn.transform( new (C) ConvL2INode(a)));
     break;
   case Bytecodes::_i2l:
     a = pop();
     b = _gvn.transform( new (C) ConvI2LNode(a));
     push_pair(b);
     break;
   case Bytecodes::_i2b:
     // Sign extend
     a = pop();
     a = _gvn.transform( new (C) LShiftINode(a,_gvn.intcon(24)) );
     a = _gvn.transform( new (C) RShiftINode(a,_gvn.intcon(24)) );
     push( a );
     break;
   case Bytecodes::_i2s:
     a = pop();
     a = _gvn.transform( new (C) LShiftINode(a,_gvn.intcon(16)) );
     a = _gvn.transform( new (C) RShiftINode(a,_gvn.intcon(16)) );
     push( a );
     break;
   case Bytecodes::_i2c:
     a = pop();
     push( _gvn.transform( new (C) AndINode(a,_gvn.intcon(0xFFFF)) ) );
     break;
   case Bytecodes::_i2f:
     a = pop();
     b = _gvn.transform( new (C) ConvI2FNode(a) ) ;
     c = precision_rounding(b);
     push (b);
     break;
   case Bytecodes::_i2d:
     a = pop();
     b = _gvn.transform( new (C) ConvI2DNode(a));
     push_pair(b);
     break;
   case Bytecodes::_iinc:        // Increment local
     i = iter().get_index();     // Get local index
     set_local( i, _gvn.transform( new (C) AddINode( _gvn.intcon(iter().get_iinc_con()), local(i) ) ) );
     break;
   // Exit points of synchronized methods must have an unlock node
   case Bytecodes::_return:
     return_current(NULL);
     break;
   case Bytecodes::_ireturn:
   case Bytecodes::_areturn:
   case Bytecodes::_freturn:
     return_current(pop());
     break;
   case Bytecodes::_lreturn:
     return_current(pop_pair());
     break;
   case Bytecodes::_dreturn:
     return_current(pop_pair());
     break;
   case Bytecodes::_athrow:
     // null exception oop throws NULL pointer exception
     null_check(peek());
     if (stopped())  return;
     // Hook the thrown exception directly to subsequent handlers.
     if (BailoutToInterpreterForThrows) {
       // Keep method interpreted from now on.
       uncommon_trap(Deoptimization::Reason_unhandled,
                     Deoptimization::Action_make_not_compilable);
       return;
     }
     if (env()->jvmti_can_post_on_exceptions()) {
       // check if we must post exception events, take uncommon trap if so (with must_throw = false)
       uncommon_trap_if_should_post_on_exceptions(Deoptimization::Reason_unhandled, false);
     }
     // Here if either can_post_on_exceptions or should_post_on_exceptions is false
     add_exception_state(make_exception_state(peek()));
     break;
   case Bytecodes::_goto:   // fall through
   case Bytecodes::_goto_w: {
     int target_bci = (bc() == Bytecodes::_goto) ? iter().get_dest() : iter().get_far_dest();
     // If this is a backwards branch in the bytecodes, add Safepoint
     maybe_add_safepoint(target_bci);
     // Update method data
     profile_taken_branch(target_bci);
     // Merge the current control into the target basic block
     merge(target_bci);
     // See if we can get some profile data and hand it off to the next block
     Block *target_block = block()->successor_for_bci(target_bci);
     if (target_block->pred_count() != 1)  break;
     ciMethodData* methodData = method()->method_data();
     if (!methodData->is_mature())  break;
     ciProfileData* data = methodData->bci_to_data(bci());
     assert( data->is_JumpData(), "" );
     int taken = ((ciJumpData*)data)->taken();
     taken = method()->scale_count(taken);
     target_block->set_count(taken);
     break;
   }
   case Bytecodes::_ifnull:    btest = BoolTest::eq; goto handle_if_null;
   case Bytecodes::_ifnonnull: btest = BoolTest::ne; goto handle_if_null;
   handle_if_null:
     // If this is a backwards branch in the bytecodes, add Safepoint
     maybe_add_safepoint(iter().get_dest());
     a = null();
     b = pop();
     c = _gvn.transform( new (C) CmpPNode(b, a) );
     do_ifnull(btest, c);
     break;
   case Bytecodes::_if_acmpeq: btest = BoolTest::eq; goto handle_if_acmp;
   case Bytecodes::_if_acmpne: btest = BoolTest::ne; goto handle_if_acmp;
   handle_if_acmp:
     // If this is a backwards branch in the bytecodes, add Safepoint
     maybe_add_safepoint(iter().get_dest());
     a = pop();
     b = pop();
     c = _gvn.transform( new (C) CmpPNode(b, a) );
     do_if(btest, c);
     break;
   case Bytecodes::_ifeq: btest = BoolTest::eq; goto handle_ifxx;
   case Bytecodes::_ifne: btest = BoolTest::ne; goto handle_ifxx;
   case Bytecodes::_iflt: btest = BoolTest::lt; goto handle_ifxx;
   case Bytecodes::_ifle: btest = BoolTest::le; goto handle_ifxx;
   case Bytecodes::_ifgt: btest = BoolTest::gt; goto handle_ifxx;
   case Bytecodes::_ifge: btest = BoolTest::ge; goto handle_ifxx;
   handle_ifxx:
     // If this is a backwards branch in the bytecodes, add Safepoint
     maybe_add_safepoint(iter().get_dest());
     a = _gvn.intcon(0);
     b = pop();
     c = _gvn.transform( new (C) CmpINode(b, a) );
     do_if(btest, c);
     break;
   case Bytecodes::_if_icmpeq: btest = BoolTest::eq; goto handle_if_icmp;
   case Bytecodes::_if_icmpne: btest = BoolTest::ne; goto handle_if_icmp;
   case Bytecodes::_if_icmplt: btest = BoolTest::lt; goto handle_if_icmp;
   case Bytecodes::_if_icmple: btest = BoolTest::le; goto handle_if_icmp;
   case Bytecodes::_if_icmpgt: btest = BoolTest::gt; goto handle_if_icmp;
   case Bytecodes::_if_icmpge: btest = BoolTest::ge; goto handle_if_icmp;
   handle_if_icmp:
     // If this is a backwards branch in the bytecodes, add Safepoint
     maybe_add_safepoint(iter().get_dest());
     a = pop();
     b = pop();
     c = _gvn.transform( new (C) CmpINode( b, a ) );
     do_if(btest, c);
     break;
   case Bytecodes::_tableswitch:
     do_tableswitch();
     break;
   case Bytecodes::_lookupswitch:
     do_lookupswitch();
     break;
   case Bytecodes::_invokestatic:
   case Bytecodes::_invokedynamic:
   case Bytecodes::_invokespecial:
   case Bytecodes::_invokevirtual:
   case Bytecodes::_invokeinterface:
     do_call();
     break;
   case Bytecodes::_checkcast:
     do_checkcast();
     break;
   case Bytecodes::_instanceof:
     do_instanceof();
     break;
   case Bytecodes::_anewarray:
     do_anewarray();
     break;
   case Bytecodes::_newarray:
     do_newarray((BasicType)iter().get_index());
     break;
   case Bytecodes::_multianewarray:
     do_multianewarray();
     break;
   case Bytecodes::_new:
     do_new();
     break;
   case Bytecodes::_jsr:
   case Bytecodes::_jsr_w:
     do_jsr();
     break;
   case Bytecodes::_ret:
     do_ret();
     break;
   case Bytecodes::_monitorenter:
     do_monitor_enter();
     break;
   case Bytecodes::_monitorexit:
     do_monitor_exit();
     break;
   case Bytecodes::_breakpoint:
     // Breakpoint set concurrently to compile
     // %%% use an uncommon trap?
     C->record_failure("breakpoint in method");
     return;
   default:
 #ifndef PRODUCT
     map()->dump(99);
 #endif
     tty->print("\nUnhandled bytecode %s\n", Bytecodes::name(bc()) );
     ShouldNotReachHere();
   }
 #ifndef PRODUCT
   IdealGraphPrinter *printer = IdealGraphPrinter::printer();
   if(printer) {
     char buffer[256];
     sprintf(buffer, "Bytecode %d: %s", bci(), Bytecodes::name(bc()));
     bool old = printer->traverse_outs();
     printer->set_traverse_outs(true);
     printer->print_method(C, buffer, 4);
     printer->set_traverse_outs(old);
   }
 #endif
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/opto/parse2.cpp@beebba0acc11 (annotated)

src/share/vm/opto/parse2.cpp