hotspot/src/share/vm/opto/compile.cpp
changeset 1 489c9b5090e2
child 211 e2b60448c234
equal deleted inserted replaced
0:fd16c54261b3 1:489c9b5090e2
       
     1 /*
       
     2  * Copyright 1997-2007 Sun Microsystems, Inc.  All Rights Reserved.
       
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
       
     4  *
       
     5  * This code is free software; you can redistribute it and/or modify it
       
     6  * under the terms of the GNU General Public License version 2 only, as
       
     7  * published by the Free Software Foundation.
       
     8  *
       
     9  * This code is distributed in the hope that it will be useful, but WITHOUT
       
    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
       
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
       
    12  * version 2 for more details (a copy is included in the LICENSE file that
       
    13  * accompanied this code).
       
    14  *
       
    15  * You should have received a copy of the GNU General Public License version
       
    16  * 2 along with this work; if not, write to the Free Software Foundation,
       
    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
       
    18  *
       
    19  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
       
    20  * CA 95054 USA or visit www.sun.com if you need additional information or
       
    21  * have any questions.
       
    22  *
       
    23  */
       
    24 
       
    25 #include "incls/_precompiled.incl"
       
    26 #include "incls/_compile.cpp.incl"
       
    27 
       
    28 /// Support for intrinsics.
       
    29 
       
    30 // Return the index at which m must be inserted (or already exists).
       
    31 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
       
    32 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual) {
       
    33 #ifdef ASSERT
       
    34   for (int i = 1; i < _intrinsics->length(); i++) {
       
    35     CallGenerator* cg1 = _intrinsics->at(i-1);
       
    36     CallGenerator* cg2 = _intrinsics->at(i);
       
    37     assert(cg1->method() != cg2->method()
       
    38            ? cg1->method()     < cg2->method()
       
    39            : cg1->is_virtual() < cg2->is_virtual(),
       
    40            "compiler intrinsics list must stay sorted");
       
    41   }
       
    42 #endif
       
    43   // Binary search sorted list, in decreasing intervals [lo, hi].
       
    44   int lo = 0, hi = _intrinsics->length()-1;
       
    45   while (lo <= hi) {
       
    46     int mid = (uint)(hi + lo) / 2;
       
    47     ciMethod* mid_m = _intrinsics->at(mid)->method();
       
    48     if (m < mid_m) {
       
    49       hi = mid-1;
       
    50     } else if (m > mid_m) {
       
    51       lo = mid+1;
       
    52     } else {
       
    53       // look at minor sort key
       
    54       bool mid_virt = _intrinsics->at(mid)->is_virtual();
       
    55       if (is_virtual < mid_virt) {
       
    56         hi = mid-1;
       
    57       } else if (is_virtual > mid_virt) {
       
    58         lo = mid+1;
       
    59       } else {
       
    60         return mid;  // exact match
       
    61       }
       
    62     }
       
    63   }
       
    64   return lo;  // inexact match
       
    65 }
       
    66 
       
    67 void Compile::register_intrinsic(CallGenerator* cg) {
       
    68   if (_intrinsics == NULL) {
       
    69     _intrinsics = new GrowableArray<CallGenerator*>(60);
       
    70   }
       
    71   // This code is stolen from ciObjectFactory::insert.
       
    72   // Really, GrowableArray should have methods for
       
    73   // insert_at, remove_at, and binary_search.
       
    74   int len = _intrinsics->length();
       
    75   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual());
       
    76   if (index == len) {
       
    77     _intrinsics->append(cg);
       
    78   } else {
       
    79 #ifdef ASSERT
       
    80     CallGenerator* oldcg = _intrinsics->at(index);
       
    81     assert(oldcg->method() != cg->method() || oldcg->is_virtual() != cg->is_virtual(), "don't register twice");
       
    82 #endif
       
    83     _intrinsics->append(_intrinsics->at(len-1));
       
    84     int pos;
       
    85     for (pos = len-2; pos >= index; pos--) {
       
    86       _intrinsics->at_put(pos+1,_intrinsics->at(pos));
       
    87     }
       
    88     _intrinsics->at_put(index, cg);
       
    89   }
       
    90   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
       
    91 }
       
    92 
       
    93 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
       
    94   assert(m->is_loaded(), "don't try this on unloaded methods");
       
    95   if (_intrinsics != NULL) {
       
    96     int index = intrinsic_insertion_index(m, is_virtual);
       
    97     if (index < _intrinsics->length()
       
    98         && _intrinsics->at(index)->method() == m
       
    99         && _intrinsics->at(index)->is_virtual() == is_virtual) {
       
   100       return _intrinsics->at(index);
       
   101     }
       
   102   }
       
   103   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
       
   104   if (m->intrinsic_id() != vmIntrinsics::_none) {
       
   105     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
       
   106     if (cg != NULL) {
       
   107       // Save it for next time:
       
   108       register_intrinsic(cg);
       
   109       return cg;
       
   110     } else {
       
   111       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
       
   112     }
       
   113   }
       
   114   return NULL;
       
   115 }
       
   116 
       
   117 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
       
   118 // in library_call.cpp.
       
   119 
       
   120 
       
   121 #ifndef PRODUCT
       
   122 // statistics gathering...
       
   123 
       
   124 juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
       
   125 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
       
   126 
       
   127 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
       
   128   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
       
   129   int oflags = _intrinsic_hist_flags[id];
       
   130   assert(flags != 0, "what happened?");
       
   131   if (is_virtual) {
       
   132     flags |= _intrinsic_virtual;
       
   133   }
       
   134   bool changed = (flags != oflags);
       
   135   if ((flags & _intrinsic_worked) != 0) {
       
   136     juint count = (_intrinsic_hist_count[id] += 1);
       
   137     if (count == 1) {
       
   138       changed = true;           // first time
       
   139     }
       
   140     // increment the overall count also:
       
   141     _intrinsic_hist_count[vmIntrinsics::_none] += 1;
       
   142   }
       
   143   if (changed) {
       
   144     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
       
   145       // Something changed about the intrinsic's virtuality.
       
   146       if ((flags & _intrinsic_virtual) != 0) {
       
   147         // This is the first use of this intrinsic as a virtual call.
       
   148         if (oflags != 0) {
       
   149           // We already saw it as a non-virtual, so note both cases.
       
   150           flags |= _intrinsic_both;
       
   151         }
       
   152       } else if ((oflags & _intrinsic_both) == 0) {
       
   153         // This is the first use of this intrinsic as a non-virtual
       
   154         flags |= _intrinsic_both;
       
   155       }
       
   156     }
       
   157     _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
       
   158   }
       
   159   // update the overall flags also:
       
   160   _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
       
   161   return changed;
       
   162 }
       
   163 
       
   164 static char* format_flags(int flags, char* buf) {
       
   165   buf[0] = 0;
       
   166   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
       
   167   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
       
   168   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
       
   169   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
       
   170   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
       
   171   if (buf[0] == 0)  strcat(buf, ",");
       
   172   assert(buf[0] == ',', "must be");
       
   173   return &buf[1];
       
   174 }
       
   175 
       
   176 void Compile::print_intrinsic_statistics() {
       
   177   char flagsbuf[100];
       
   178   ttyLocker ttyl;
       
   179   if (xtty != NULL)  xtty->head("statistics type='intrinsic'");
       
   180   tty->print_cr("Compiler intrinsic usage:");
       
   181   juint total = _intrinsic_hist_count[vmIntrinsics::_none];
       
   182   if (total == 0)  total = 1;  // avoid div0 in case of no successes
       
   183   #define PRINT_STAT_LINE(name, c, f) \
       
   184     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
       
   185   for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
       
   186     vmIntrinsics::ID id = (vmIntrinsics::ID) index;
       
   187     int   flags = _intrinsic_hist_flags[id];
       
   188     juint count = _intrinsic_hist_count[id];
       
   189     if ((flags | count) != 0) {
       
   190       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
       
   191     }
       
   192   }
       
   193   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
       
   194   if (xtty != NULL)  xtty->tail("statistics");
       
   195 }
       
   196 
       
   197 void Compile::print_statistics() {
       
   198   { ttyLocker ttyl;
       
   199     if (xtty != NULL)  xtty->head("statistics type='opto'");
       
   200     Parse::print_statistics();
       
   201     PhaseCCP::print_statistics();
       
   202     PhaseRegAlloc::print_statistics();
       
   203     Scheduling::print_statistics();
       
   204     PhasePeephole::print_statistics();
       
   205     PhaseIdealLoop::print_statistics();
       
   206     if (xtty != NULL)  xtty->tail("statistics");
       
   207   }
       
   208   if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
       
   209     // put this under its own <statistics> element.
       
   210     print_intrinsic_statistics();
       
   211   }
       
   212 }
       
   213 #endif //PRODUCT
       
   214 
       
   215 // Support for bundling info
       
   216 Bundle* Compile::node_bundling(const Node *n) {
       
   217   assert(valid_bundle_info(n), "oob");
       
   218   return &_node_bundling_base[n->_idx];
       
   219 }
       
   220 
       
   221 bool Compile::valid_bundle_info(const Node *n) {
       
   222   return (_node_bundling_limit > n->_idx);
       
   223 }
       
   224 
       
   225 
       
   226 // Identify all nodes that are reachable from below, useful.
       
   227 // Use breadth-first pass that records state in a Unique_Node_List,
       
   228 // recursive traversal is slower.
       
   229 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
       
   230   int estimated_worklist_size = unique();
       
   231   useful.map( estimated_worklist_size, NULL );  // preallocate space
       
   232 
       
   233   // Initialize worklist
       
   234   if (root() != NULL)     { useful.push(root()); }
       
   235   // If 'top' is cached, declare it useful to preserve cached node
       
   236   if( cached_top_node() ) { useful.push(cached_top_node()); }
       
   237 
       
   238   // Push all useful nodes onto the list, breadthfirst
       
   239   for( uint next = 0; next < useful.size(); ++next ) {
       
   240     assert( next < unique(), "Unique useful nodes < total nodes");
       
   241     Node *n  = useful.at(next);
       
   242     uint max = n->len();
       
   243     for( uint i = 0; i < max; ++i ) {
       
   244       Node *m = n->in(i);
       
   245       if( m == NULL ) continue;
       
   246       useful.push(m);
       
   247     }
       
   248   }
       
   249 }
       
   250 
       
   251 // Disconnect all useless nodes by disconnecting those at the boundary.
       
   252 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
       
   253   uint next = 0;
       
   254   while( next < useful.size() ) {
       
   255     Node *n = useful.at(next++);
       
   256     // Use raw traversal of out edges since this code removes out edges
       
   257     int max = n->outcnt();
       
   258     for (int j = 0; j < max; ++j ) {
       
   259       Node* child = n->raw_out(j);
       
   260       if( ! useful.member(child) ) {
       
   261         assert( !child->is_top() || child != top(),
       
   262                 "If top is cached in Compile object it is in useful list");
       
   263         // Only need to remove this out-edge to the useless node
       
   264         n->raw_del_out(j);
       
   265         --j;
       
   266         --max;
       
   267       }
       
   268     }
       
   269     if (n->outcnt() == 1 && n->has_special_unique_user()) {
       
   270       record_for_igvn( n->unique_out() );
       
   271     }
       
   272   }
       
   273   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
       
   274 }
       
   275 
       
   276 //------------------------------frame_size_in_words-----------------------------
       
   277 // frame_slots in units of words
       
   278 int Compile::frame_size_in_words() const {
       
   279   // shift is 0 in LP32 and 1 in LP64
       
   280   const int shift = (LogBytesPerWord - LogBytesPerInt);
       
   281   int words = _frame_slots >> shift;
       
   282   assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
       
   283   return words;
       
   284 }
       
   285 
       
   286 // ============================================================================
       
   287 //------------------------------CompileWrapper---------------------------------
       
   288 class CompileWrapper : public StackObj {
       
   289   Compile *const _compile;
       
   290  public:
       
   291   CompileWrapper(Compile* compile);
       
   292 
       
   293   ~CompileWrapper();
       
   294 };
       
   295 
       
   296 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
       
   297   // the Compile* pointer is stored in the current ciEnv:
       
   298   ciEnv* env = compile->env();
       
   299   assert(env == ciEnv::current(), "must already be a ciEnv active");
       
   300   assert(env->compiler_data() == NULL, "compile already active?");
       
   301   env->set_compiler_data(compile);
       
   302   assert(compile == Compile::current(), "sanity");
       
   303 
       
   304   compile->set_type_dict(NULL);
       
   305   compile->set_type_hwm(NULL);
       
   306   compile->set_type_last_size(0);
       
   307   compile->set_last_tf(NULL, NULL);
       
   308   compile->set_indexSet_arena(NULL);
       
   309   compile->set_indexSet_free_block_list(NULL);
       
   310   compile->init_type_arena();
       
   311   Type::Initialize(compile);
       
   312   _compile->set_scratch_buffer_blob(NULL);
       
   313   _compile->begin_method();
       
   314 }
       
   315 CompileWrapper::~CompileWrapper() {
       
   316   if (_compile->failing()) {
       
   317     _compile->print_method("Failed");
       
   318   }
       
   319   _compile->end_method();
       
   320   if (_compile->scratch_buffer_blob() != NULL)
       
   321     BufferBlob::free(_compile->scratch_buffer_blob());
       
   322   _compile->env()->set_compiler_data(NULL);
       
   323 }
       
   324 
       
   325 
       
   326 //----------------------------print_compile_messages---------------------------
       
   327 void Compile::print_compile_messages() {
       
   328 #ifndef PRODUCT
       
   329   // Check if recompiling
       
   330   if (_subsume_loads == false && PrintOpto) {
       
   331     // Recompiling without allowing machine instructions to subsume loads
       
   332     tty->print_cr("*********************************************************");
       
   333     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
       
   334     tty->print_cr("*********************************************************");
       
   335   }
       
   336   if (env()->break_at_compile()) {
       
   337     // Open the debugger when compiing this method.
       
   338     tty->print("### Breaking when compiling: ");
       
   339     method()->print_short_name();
       
   340     tty->cr();
       
   341     BREAKPOINT;
       
   342   }
       
   343 
       
   344   if( PrintOpto ) {
       
   345     if (is_osr_compilation()) {
       
   346       tty->print("[OSR]%3d", _compile_id);
       
   347     } else {
       
   348       tty->print("%3d", _compile_id);
       
   349     }
       
   350   }
       
   351 #endif
       
   352 }
       
   353 
       
   354 
       
   355 void Compile::init_scratch_buffer_blob() {
       
   356   if( scratch_buffer_blob() != NULL )  return;
       
   357 
       
   358   // Construct a temporary CodeBuffer to have it construct a BufferBlob
       
   359   // Cache this BufferBlob for this compile.
       
   360   ResourceMark rm;
       
   361   int size = (MAX_inst_size + MAX_stubs_size + MAX_const_size);
       
   362   BufferBlob* blob = BufferBlob::create("Compile::scratch_buffer", size);
       
   363   // Record the buffer blob for next time.
       
   364   set_scratch_buffer_blob(blob);
       
   365   guarantee(scratch_buffer_blob() != NULL, "Need BufferBlob for code generation");
       
   366 
       
   367   // Initialize the relocation buffers
       
   368   relocInfo* locs_buf = (relocInfo*) blob->instructions_end() - MAX_locs_size;
       
   369   set_scratch_locs_memory(locs_buf);
       
   370 }
       
   371 
       
   372 
       
   373 //-----------------------scratch_emit_size-------------------------------------
       
   374 // Helper function that computes size by emitting code
       
   375 uint Compile::scratch_emit_size(const Node* n) {
       
   376   // Emit into a trash buffer and count bytes emitted.
       
   377   // This is a pretty expensive way to compute a size,
       
   378   // but it works well enough if seldom used.
       
   379   // All common fixed-size instructions are given a size
       
   380   // method by the AD file.
       
   381   // Note that the scratch buffer blob and locs memory are
       
   382   // allocated at the beginning of the compile task, and
       
   383   // may be shared by several calls to scratch_emit_size.
       
   384   // The allocation of the scratch buffer blob is particularly
       
   385   // expensive, since it has to grab the code cache lock.
       
   386   BufferBlob* blob = this->scratch_buffer_blob();
       
   387   assert(blob != NULL, "Initialize BufferBlob at start");
       
   388   assert(blob->size() > MAX_inst_size, "sanity");
       
   389   relocInfo* locs_buf = scratch_locs_memory();
       
   390   address blob_begin = blob->instructions_begin();
       
   391   address blob_end   = (address)locs_buf;
       
   392   assert(blob->instructions_contains(blob_end), "sanity");
       
   393   CodeBuffer buf(blob_begin, blob_end - blob_begin);
       
   394   buf.initialize_consts_size(MAX_const_size);
       
   395   buf.initialize_stubs_size(MAX_stubs_size);
       
   396   assert(locs_buf != NULL, "sanity");
       
   397   int lsize = MAX_locs_size / 2;
       
   398   buf.insts()->initialize_shared_locs(&locs_buf[0],     lsize);
       
   399   buf.stubs()->initialize_shared_locs(&locs_buf[lsize], lsize);
       
   400   n->emit(buf, this->regalloc());
       
   401   return buf.code_size();
       
   402 }
       
   403 
       
   404 void  Compile::record_for_escape_analysis(Node* n) {
       
   405   if (_congraph != NULL)
       
   406     _congraph->record_for_escape_analysis(n);
       
   407 }
       
   408 
       
   409 
       
   410 // ============================================================================
       
   411 //------------------------------Compile standard-------------------------------
       
   412 debug_only( int Compile::_debug_idx = 100000; )
       
   413 
       
   414 // Compile a method.  entry_bci is -1 for normal compilations and indicates
       
   415 // the continuation bci for on stack replacement.
       
   416 
       
   417 
       
   418 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci, bool subsume_loads )
       
   419                 : Phase(Compiler),
       
   420                   _env(ci_env),
       
   421                   _log(ci_env->log()),
       
   422                   _compile_id(ci_env->compile_id()),
       
   423                   _save_argument_registers(false),
       
   424                   _stub_name(NULL),
       
   425                   _stub_function(NULL),
       
   426                   _stub_entry_point(NULL),
       
   427                   _method(target),
       
   428                   _entry_bci(osr_bci),
       
   429                   _initial_gvn(NULL),
       
   430                   _for_igvn(NULL),
       
   431                   _warm_calls(NULL),
       
   432                   _subsume_loads(subsume_loads),
       
   433                   _failure_reason(NULL),
       
   434                   _code_buffer("Compile::Fill_buffer"),
       
   435                   _orig_pc_slot(0),
       
   436                   _orig_pc_slot_offset_in_bytes(0),
       
   437                   _node_bundling_limit(0),
       
   438                   _node_bundling_base(NULL),
       
   439 #ifndef PRODUCT
       
   440                   _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
       
   441                   _printer(IdealGraphPrinter::printer()),
       
   442 #endif
       
   443                   _congraph(NULL) {
       
   444   C = this;
       
   445 
       
   446   CompileWrapper cw(this);
       
   447 #ifndef PRODUCT
       
   448   if (TimeCompiler2) {
       
   449     tty->print(" ");
       
   450     target->holder()->name()->print();
       
   451     tty->print(".");
       
   452     target->print_short_name();
       
   453     tty->print("  ");
       
   454   }
       
   455   TraceTime t1("Total compilation time", &_t_totalCompilation, TimeCompiler, TimeCompiler2);
       
   456   TraceTime t2(NULL, &_t_methodCompilation, TimeCompiler, false);
       
   457   set_print_assembly(PrintOptoAssembly || _method->should_print_assembly());
       
   458 #endif
       
   459 
       
   460   if (ProfileTraps) {
       
   461     // Make sure the method being compiled gets its own MDO,
       
   462     // so we can at least track the decompile_count().
       
   463     method()->build_method_data();
       
   464   }
       
   465 
       
   466   Init(::AliasLevel);
       
   467 
       
   468 
       
   469   print_compile_messages();
       
   470 
       
   471   if (UseOldInlining || PrintCompilation NOT_PRODUCT( || PrintOpto) )
       
   472     _ilt = InlineTree::build_inline_tree_root();
       
   473   else
       
   474     _ilt = NULL;
       
   475 
       
   476   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
       
   477   assert(num_alias_types() >= AliasIdxRaw, "");
       
   478 
       
   479 #define MINIMUM_NODE_HASH  1023
       
   480   // Node list that Iterative GVN will start with
       
   481   Unique_Node_List for_igvn(comp_arena());
       
   482   set_for_igvn(&for_igvn);
       
   483 
       
   484   // GVN that will be run immediately on new nodes
       
   485   uint estimated_size = method()->code_size()*4+64;
       
   486   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
       
   487   PhaseGVN gvn(node_arena(), estimated_size);
       
   488   set_initial_gvn(&gvn);
       
   489 
       
   490   if (DoEscapeAnalysis)
       
   491     _congraph = new ConnectionGraph(this);
       
   492 
       
   493   { // Scope for timing the parser
       
   494     TracePhase t3("parse", &_t_parser, true);
       
   495 
       
   496     // Put top into the hash table ASAP.
       
   497     initial_gvn()->transform_no_reclaim(top());
       
   498 
       
   499     // Set up tf(), start(), and find a CallGenerator.
       
   500     CallGenerator* cg;
       
   501     if (is_osr_compilation()) {
       
   502       const TypeTuple *domain = StartOSRNode::osr_domain();
       
   503       const TypeTuple *range = TypeTuple::make_range(method()->signature());
       
   504       init_tf(TypeFunc::make(domain, range));
       
   505       StartNode* s = new (this, 2) StartOSRNode(root(), domain);
       
   506       initial_gvn()->set_type_bottom(s);
       
   507       init_start(s);
       
   508       cg = CallGenerator::for_osr(method(), entry_bci());
       
   509     } else {
       
   510       // Normal case.
       
   511       init_tf(TypeFunc::make(method()));
       
   512       StartNode* s = new (this, 2) StartNode(root(), tf()->domain());
       
   513       initial_gvn()->set_type_bottom(s);
       
   514       init_start(s);
       
   515       float past_uses = method()->interpreter_invocation_count();
       
   516       float expected_uses = past_uses;
       
   517       cg = CallGenerator::for_inline(method(), expected_uses);
       
   518     }
       
   519     if (failing())  return;
       
   520     if (cg == NULL) {
       
   521       record_method_not_compilable_all_tiers("cannot parse method");
       
   522       return;
       
   523     }
       
   524     JVMState* jvms = build_start_state(start(), tf());
       
   525     if ((jvms = cg->generate(jvms)) == NULL) {
       
   526       record_method_not_compilable("method parse failed");
       
   527       return;
       
   528     }
       
   529     GraphKit kit(jvms);
       
   530 
       
   531     if (!kit.stopped()) {
       
   532       // Accept return values, and transfer control we know not where.
       
   533       // This is done by a special, unique ReturnNode bound to root.
       
   534       return_values(kit.jvms());
       
   535     }
       
   536 
       
   537     if (kit.has_exceptions()) {
       
   538       // Any exceptions that escape from this call must be rethrown
       
   539       // to whatever caller is dynamically above us on the stack.
       
   540       // This is done by a special, unique RethrowNode bound to root.
       
   541       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
       
   542     }
       
   543 
       
   544     // Remove clutter produced by parsing.
       
   545     if (!failing()) {
       
   546       ResourceMark rm;
       
   547       PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
       
   548     }
       
   549   }
       
   550 
       
   551   // Note:  Large methods are capped off in do_one_bytecode().
       
   552   if (failing())  return;
       
   553 
       
   554   // After parsing, node notes are no longer automagic.
       
   555   // They must be propagated by register_new_node_with_optimizer(),
       
   556   // clone(), or the like.
       
   557   set_default_node_notes(NULL);
       
   558 
       
   559   for (;;) {
       
   560     int successes = Inline_Warm();
       
   561     if (failing())  return;
       
   562     if (successes == 0)  break;
       
   563   }
       
   564 
       
   565   // Drain the list.
       
   566   Finish_Warm();
       
   567 #ifndef PRODUCT
       
   568   if (_printer) {
       
   569     _printer->print_inlining(this);
       
   570   }
       
   571 #endif
       
   572 
       
   573   if (failing())  return;
       
   574   NOT_PRODUCT( verify_graph_edges(); )
       
   575 
       
   576   // Perform escape analysis
       
   577   if (_congraph != NULL) {
       
   578     NOT_PRODUCT( TracePhase t2("escapeAnalysis", &_t_escapeAnalysis, TimeCompiler); )
       
   579     _congraph->compute_escape();
       
   580 #ifndef PRODUCT
       
   581     if (PrintEscapeAnalysis) {
       
   582       _congraph->dump();
       
   583     }
       
   584 #endif
       
   585   }
       
   586   // Now optimize
       
   587   Optimize();
       
   588   if (failing())  return;
       
   589   NOT_PRODUCT( verify_graph_edges(); )
       
   590 
       
   591 #ifndef PRODUCT
       
   592   if (PrintIdeal) {
       
   593     ttyLocker ttyl;  // keep the following output all in one block
       
   594     // This output goes directly to the tty, not the compiler log.
       
   595     // To enable tools to match it up with the compilation activity,
       
   596     // be sure to tag this tty output with the compile ID.
       
   597     if (xtty != NULL) {
       
   598       xtty->head("ideal compile_id='%d'%s", compile_id(),
       
   599                  is_osr_compilation()    ? " compile_kind='osr'" :
       
   600                  "");
       
   601     }
       
   602     root()->dump(9999);
       
   603     if (xtty != NULL) {
       
   604       xtty->tail("ideal");
       
   605     }
       
   606   }
       
   607 #endif
       
   608 
       
   609   // Now that we know the size of all the monitors we can add a fixed slot
       
   610   // for the original deopt pc.
       
   611 
       
   612   _orig_pc_slot =  fixed_slots();
       
   613   int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
       
   614   set_fixed_slots(next_slot);
       
   615 
       
   616   // Now generate code
       
   617   Code_Gen();
       
   618   if (failing())  return;
       
   619 
       
   620   // Check if we want to skip execution of all compiled code.
       
   621   {
       
   622 #ifndef PRODUCT
       
   623     if (OptoNoExecute) {
       
   624       record_method_not_compilable("+OptoNoExecute");  // Flag as failed
       
   625       return;
       
   626     }
       
   627     TracePhase t2("install_code", &_t_registerMethod, TimeCompiler);
       
   628 #endif
       
   629 
       
   630     if (is_osr_compilation()) {
       
   631       _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
       
   632       _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
       
   633     } else {
       
   634       _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
       
   635       _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
       
   636     }
       
   637 
       
   638     env()->register_method(_method, _entry_bci,
       
   639                            &_code_offsets,
       
   640                            _orig_pc_slot_offset_in_bytes,
       
   641                            code_buffer(),
       
   642                            frame_size_in_words(), _oop_map_set,
       
   643                            &_handler_table, &_inc_table,
       
   644                            compiler,
       
   645                            env()->comp_level(),
       
   646                            true, /*has_debug_info*/
       
   647                            has_unsafe_access()
       
   648                            );
       
   649   }
       
   650 }
       
   651 
       
   652 //------------------------------Compile----------------------------------------
       
   653 // Compile a runtime stub
       
   654 Compile::Compile( ciEnv* ci_env,
       
   655                   TypeFunc_generator generator,
       
   656                   address stub_function,
       
   657                   const char *stub_name,
       
   658                   int is_fancy_jump,
       
   659                   bool pass_tls,
       
   660                   bool save_arg_registers,
       
   661                   bool return_pc )
       
   662   : Phase(Compiler),
       
   663     _env(ci_env),
       
   664     _log(ci_env->log()),
       
   665     _compile_id(-1),
       
   666     _save_argument_registers(save_arg_registers),
       
   667     _method(NULL),
       
   668     _stub_name(stub_name),
       
   669     _stub_function(stub_function),
       
   670     _stub_entry_point(NULL),
       
   671     _entry_bci(InvocationEntryBci),
       
   672     _initial_gvn(NULL),
       
   673     _for_igvn(NULL),
       
   674     _warm_calls(NULL),
       
   675     _orig_pc_slot(0),
       
   676     _orig_pc_slot_offset_in_bytes(0),
       
   677     _subsume_loads(true),
       
   678     _failure_reason(NULL),
       
   679     _code_buffer("Compile::Fill_buffer"),
       
   680     _node_bundling_limit(0),
       
   681     _node_bundling_base(NULL),
       
   682 #ifndef PRODUCT
       
   683     _trace_opto_output(TraceOptoOutput),
       
   684     _printer(NULL),
       
   685 #endif
       
   686     _congraph(NULL) {
       
   687   C = this;
       
   688 
       
   689 #ifndef PRODUCT
       
   690   TraceTime t1(NULL, &_t_totalCompilation, TimeCompiler, false);
       
   691   TraceTime t2(NULL, &_t_stubCompilation, TimeCompiler, false);
       
   692   set_print_assembly(PrintFrameConverterAssembly);
       
   693 #endif
       
   694   CompileWrapper cw(this);
       
   695   Init(/*AliasLevel=*/ 0);
       
   696   init_tf((*generator)());
       
   697 
       
   698   {
       
   699     // The following is a dummy for the sake of GraphKit::gen_stub
       
   700     Unique_Node_List for_igvn(comp_arena());
       
   701     set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
       
   702     PhaseGVN gvn(Thread::current()->resource_area(),255);
       
   703     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
       
   704     gvn.transform_no_reclaim(top());
       
   705 
       
   706     GraphKit kit;
       
   707     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
       
   708   }
       
   709 
       
   710   NOT_PRODUCT( verify_graph_edges(); )
       
   711   Code_Gen();
       
   712   if (failing())  return;
       
   713 
       
   714 
       
   715   // Entry point will be accessed using compile->stub_entry_point();
       
   716   if (code_buffer() == NULL) {
       
   717     Matcher::soft_match_failure();
       
   718   } else {
       
   719     if (PrintAssembly && (WizardMode || Verbose))
       
   720       tty->print_cr("### Stub::%s", stub_name);
       
   721 
       
   722     if (!failing()) {
       
   723       assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
       
   724 
       
   725       // Make the NMethod
       
   726       // For now we mark the frame as never safe for profile stackwalking
       
   727       RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
       
   728                                                       code_buffer(),
       
   729                                                       CodeOffsets::frame_never_safe,
       
   730                                                       // _code_offsets.value(CodeOffsets::Frame_Complete),
       
   731                                                       frame_size_in_words(),
       
   732                                                       _oop_map_set,
       
   733                                                       save_arg_registers);
       
   734       assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
       
   735 
       
   736       _stub_entry_point = rs->entry_point();
       
   737     }
       
   738   }
       
   739 }
       
   740 
       
   741 #ifndef PRODUCT
       
   742 void print_opto_verbose_signature( const TypeFunc *j_sig, const char *stub_name ) {
       
   743   if(PrintOpto && Verbose) {
       
   744     tty->print("%s   ", stub_name); j_sig->print_flattened(); tty->cr();
       
   745   }
       
   746 }
       
   747 #endif
       
   748 
       
   749 void Compile::print_codes() {
       
   750 }
       
   751 
       
   752 //------------------------------Init-------------------------------------------
       
   753 // Prepare for a single compilation
       
   754 void Compile::Init(int aliaslevel) {
       
   755   _unique  = 0;
       
   756   _regalloc = NULL;
       
   757 
       
   758   _tf      = NULL;  // filled in later
       
   759   _top     = NULL;  // cached later
       
   760   _matcher = NULL;  // filled in later
       
   761   _cfg     = NULL;  // filled in later
       
   762 
       
   763   set_24_bit_selection_and_mode(Use24BitFP, false);
       
   764 
       
   765   _node_note_array = NULL;
       
   766   _default_node_notes = NULL;
       
   767 
       
   768   _immutable_memory = NULL; // filled in at first inquiry
       
   769 
       
   770   // Globally visible Nodes
       
   771   // First set TOP to NULL to give safe behavior during creation of RootNode
       
   772   set_cached_top_node(NULL);
       
   773   set_root(new (this, 3) RootNode());
       
   774   // Now that you have a Root to point to, create the real TOP
       
   775   set_cached_top_node( new (this, 1) ConNode(Type::TOP) );
       
   776   set_recent_alloc(NULL, NULL);
       
   777 
       
   778   // Create Debug Information Recorder to record scopes, oopmaps, etc.
       
   779   env()->set_oop_recorder(new OopRecorder(comp_arena()));
       
   780   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
       
   781   env()->set_dependencies(new Dependencies(env()));
       
   782 
       
   783   _fixed_slots = 0;
       
   784   set_has_split_ifs(false);
       
   785   set_has_loops(has_method() && method()->has_loops()); // first approximation
       
   786   _deopt_happens = true;  // start out assuming the worst
       
   787   _trap_can_recompile = false;  // no traps emitted yet
       
   788   _major_progress = true; // start out assuming good things will happen
       
   789   set_has_unsafe_access(false);
       
   790   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
       
   791   set_decompile_count(0);
       
   792 
       
   793   // Compilation level related initialization
       
   794   if (env()->comp_level() == CompLevel_fast_compile) {
       
   795     set_num_loop_opts(Tier1LoopOptsCount);
       
   796     set_do_inlining(Tier1Inline != 0);
       
   797     set_max_inline_size(Tier1MaxInlineSize);
       
   798     set_freq_inline_size(Tier1FreqInlineSize);
       
   799     set_do_scheduling(false);
       
   800     set_do_count_invocations(Tier1CountInvocations);
       
   801     set_do_method_data_update(Tier1UpdateMethodData);
       
   802   } else {
       
   803     assert(env()->comp_level() == CompLevel_full_optimization, "unknown comp level");
       
   804     set_num_loop_opts(LoopOptsCount);
       
   805     set_do_inlining(Inline);
       
   806     set_max_inline_size(MaxInlineSize);
       
   807     set_freq_inline_size(FreqInlineSize);
       
   808     set_do_scheduling(OptoScheduling);
       
   809     set_do_count_invocations(false);
       
   810     set_do_method_data_update(false);
       
   811   }
       
   812 
       
   813   if (debug_info()->recording_non_safepoints()) {
       
   814     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
       
   815                         (comp_arena(), 8, 0, NULL));
       
   816     set_default_node_notes(Node_Notes::make(this));
       
   817   }
       
   818 
       
   819   // // -- Initialize types before each compile --
       
   820   // // Update cached type information
       
   821   // if( _method && _method->constants() )
       
   822   //   Type::update_loaded_types(_method, _method->constants());
       
   823 
       
   824   // Init alias_type map.
       
   825   if (!DoEscapeAnalysis && aliaslevel == 3)
       
   826     aliaslevel = 2;  // No unique types without escape analysis
       
   827   _AliasLevel = aliaslevel;
       
   828   const int grow_ats = 16;
       
   829   _max_alias_types = grow_ats;
       
   830   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
       
   831   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
       
   832   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
       
   833   {
       
   834     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
       
   835   }
       
   836   // Initialize the first few types.
       
   837   _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
       
   838   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
       
   839   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
       
   840   _num_alias_types = AliasIdxRaw+1;
       
   841   // Zero out the alias type cache.
       
   842   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
       
   843   // A NULL adr_type hits in the cache right away.  Preload the right answer.
       
   844   probe_alias_cache(NULL)->_index = AliasIdxTop;
       
   845 
       
   846   _intrinsics = NULL;
       
   847   _macro_nodes = new GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
       
   848   register_library_intrinsics();
       
   849 }
       
   850 
       
   851 //---------------------------init_start----------------------------------------
       
   852 // Install the StartNode on this compile object.
       
   853 void Compile::init_start(StartNode* s) {
       
   854   if (failing())
       
   855     return; // already failing
       
   856   assert(s == start(), "");
       
   857 }
       
   858 
       
   859 StartNode* Compile::start() const {
       
   860   assert(!failing(), "");
       
   861   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
       
   862     Node* start = root()->fast_out(i);
       
   863     if( start->is_Start() )
       
   864       return start->as_Start();
       
   865   }
       
   866   ShouldNotReachHere();
       
   867   return NULL;
       
   868 }
       
   869 
       
   870 //-------------------------------immutable_memory-------------------------------------
       
   871 // Access immutable memory
       
   872 Node* Compile::immutable_memory() {
       
   873   if (_immutable_memory != NULL) {
       
   874     return _immutable_memory;
       
   875   }
       
   876   StartNode* s = start();
       
   877   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
       
   878     Node *p = s->fast_out(i);
       
   879     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
       
   880       _immutable_memory = p;
       
   881       return _immutable_memory;
       
   882     }
       
   883   }
       
   884   ShouldNotReachHere();
       
   885   return NULL;
       
   886 }
       
   887 
       
   888 //----------------------set_cached_top_node------------------------------------
       
   889 // Install the cached top node, and make sure Node::is_top works correctly.
       
   890 void Compile::set_cached_top_node(Node* tn) {
       
   891   if (tn != NULL)  verify_top(tn);
       
   892   Node* old_top = _top;
       
   893   _top = tn;
       
   894   // Calling Node::setup_is_top allows the nodes the chance to adjust
       
   895   // their _out arrays.
       
   896   if (_top != NULL)     _top->setup_is_top();
       
   897   if (old_top != NULL)  old_top->setup_is_top();
       
   898   assert(_top == NULL || top()->is_top(), "");
       
   899 }
       
   900 
       
   901 #ifndef PRODUCT
       
   902 void Compile::verify_top(Node* tn) const {
       
   903   if (tn != NULL) {
       
   904     assert(tn->is_Con(), "top node must be a constant");
       
   905     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
       
   906     assert(tn->in(0) != NULL, "must have live top node");
       
   907   }
       
   908 }
       
   909 #endif
       
   910 
       
   911 
       
   912 ///-------------------Managing Per-Node Debug & Profile Info-------------------
       
   913 
       
   914 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
       
   915   guarantee(arr != NULL, "");
       
   916   int num_blocks = arr->length();
       
   917   if (grow_by < num_blocks)  grow_by = num_blocks;
       
   918   int num_notes = grow_by * _node_notes_block_size;
       
   919   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
       
   920   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
       
   921   while (num_notes > 0) {
       
   922     arr->append(notes);
       
   923     notes     += _node_notes_block_size;
       
   924     num_notes -= _node_notes_block_size;
       
   925   }
       
   926   assert(num_notes == 0, "exact multiple, please");
       
   927 }
       
   928 
       
   929 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
       
   930   if (source == NULL || dest == NULL)  return false;
       
   931 
       
   932   if (dest->is_Con())
       
   933     return false;               // Do not push debug info onto constants.
       
   934 
       
   935 #ifdef ASSERT
       
   936   // Leave a bread crumb trail pointing to the original node:
       
   937   if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
       
   938     dest->set_debug_orig(source);
       
   939   }
       
   940 #endif
       
   941 
       
   942   if (node_note_array() == NULL)
       
   943     return false;               // Not collecting any notes now.
       
   944 
       
   945   // This is a copy onto a pre-existing node, which may already have notes.
       
   946   // If both nodes have notes, do not overwrite any pre-existing notes.
       
   947   Node_Notes* source_notes = node_notes_at(source->_idx);
       
   948   if (source_notes == NULL || source_notes->is_clear())  return false;
       
   949   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
       
   950   if (dest_notes == NULL || dest_notes->is_clear()) {
       
   951     return set_node_notes_at(dest->_idx, source_notes);
       
   952   }
       
   953 
       
   954   Node_Notes merged_notes = (*source_notes);
       
   955   // The order of operations here ensures that dest notes will win...
       
   956   merged_notes.update_from(dest_notes);
       
   957   return set_node_notes_at(dest->_idx, &merged_notes);
       
   958 }
       
   959 
       
   960 
       
   961 //--------------------------allow_range_check_smearing-------------------------
       
   962 // Gating condition for coalescing similar range checks.
       
   963 // Sometimes we try 'speculatively' replacing a series of a range checks by a
       
   964 // single covering check that is at least as strong as any of them.
       
   965 // If the optimization succeeds, the simplified (strengthened) range check
       
   966 // will always succeed.  If it fails, we will deopt, and then give up
       
   967 // on the optimization.
       
   968 bool Compile::allow_range_check_smearing() const {
       
   969   // If this method has already thrown a range-check,
       
   970   // assume it was because we already tried range smearing
       
   971   // and it failed.
       
   972   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
       
   973   return !already_trapped;
       
   974 }
       
   975 
       
   976 
       
   977 //------------------------------flatten_alias_type-----------------------------
       
   978 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
       
   979   int offset = tj->offset();
       
   980   TypePtr::PTR ptr = tj->ptr();
       
   981 
       
   982   // Process weird unsafe references.
       
   983   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
       
   984     assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
       
   985     tj = TypeOopPtr::BOTTOM;
       
   986     ptr = tj->ptr();
       
   987     offset = tj->offset();
       
   988   }
       
   989 
       
   990   // Array pointers need some flattening
       
   991   const TypeAryPtr *ta = tj->isa_aryptr();
       
   992   if( ta && _AliasLevel >= 2 ) {
       
   993     // For arrays indexed by constant indices, we flatten the alias
       
   994     // space to include all of the array body.  Only the header, klass
       
   995     // and array length can be accessed un-aliased.
       
   996     if( offset != Type::OffsetBot ) {
       
   997       if( ta->const_oop() ) { // methodDataOop or methodOop
       
   998         offset = Type::OffsetBot;   // Flatten constant access into array body
       
   999         tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,Type::OffsetBot, ta->instance_id());
       
  1000       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
       
  1001         // range is OK as-is.
       
  1002         tj = ta = TypeAryPtr::RANGE;
       
  1003       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
       
  1004         tj = TypeInstPtr::KLASS; // all klass loads look alike
       
  1005         ta = TypeAryPtr::RANGE; // generic ignored junk
       
  1006         ptr = TypePtr::BotPTR;
       
  1007       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
       
  1008         tj = TypeInstPtr::MARK;
       
  1009         ta = TypeAryPtr::RANGE; // generic ignored junk
       
  1010         ptr = TypePtr::BotPTR;
       
  1011       } else {                  // Random constant offset into array body
       
  1012         offset = Type::OffsetBot;   // Flatten constant access into array body
       
  1013         tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,Type::OffsetBot, ta->instance_id());
       
  1014       }
       
  1015     }
       
  1016     // Arrays of fixed size alias with arrays of unknown size.
       
  1017     if (ta->size() != TypeInt::POS) {
       
  1018       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
       
  1019       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset, ta->instance_id());
       
  1020     }
       
  1021     // Arrays of known objects become arrays of unknown objects.
       
  1022     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
       
  1023       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
       
  1024       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset, ta->instance_id());
       
  1025     }
       
  1026     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
       
  1027     // cannot be distinguished by bytecode alone.
       
  1028     if (ta->elem() == TypeInt::BOOL) {
       
  1029       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
       
  1030       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
       
  1031       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset, ta->instance_id());
       
  1032     }
       
  1033     // During the 2nd round of IterGVN, NotNull castings are removed.
       
  1034     // Make sure the Bottom and NotNull variants alias the same.
       
  1035     // Also, make sure exact and non-exact variants alias the same.
       
  1036     if( ptr == TypePtr::NotNull || ta->klass_is_exact() ) {
       
  1037       if (ta->const_oop()) {
       
  1038         tj = ta = TypeAryPtr::make(TypePtr::Constant,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
       
  1039       } else {
       
  1040         tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
       
  1041       }
       
  1042     }
       
  1043   }
       
  1044 
       
  1045   // Oop pointers need some flattening
       
  1046   const TypeInstPtr *to = tj->isa_instptr();
       
  1047   if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
       
  1048     if( ptr == TypePtr::Constant ) {
       
  1049       // No constant oop pointers (such as Strings); they alias with
       
  1050       // unknown strings.
       
  1051       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
       
  1052     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
       
  1053       // During the 2nd round of IterGVN, NotNull castings are removed.
       
  1054       // Make sure the Bottom and NotNull variants alias the same.
       
  1055       // Also, make sure exact and non-exact variants alias the same.
       
  1056       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset, to->instance_id());
       
  1057     }
       
  1058     // Canonicalize the holder of this field
       
  1059     ciInstanceKlass *k = to->klass()->as_instance_klass();
       
  1060     if (offset >= 0 && offset < oopDesc::header_size() * wordSize) {
       
  1061       // First handle header references such as a LoadKlassNode, even if the
       
  1062       // object's klass is unloaded at compile time (4965979).
       
  1063       tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset, to->instance_id());
       
  1064     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
       
  1065       to = NULL;
       
  1066       tj = TypeOopPtr::BOTTOM;
       
  1067       offset = tj->offset();
       
  1068     } else {
       
  1069       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
       
  1070       if (!k->equals(canonical_holder) || tj->offset() != offset) {
       
  1071         tj = to = TypeInstPtr::make(TypePtr::BotPTR, canonical_holder, false, NULL, offset, to->instance_id());
       
  1072       }
       
  1073     }
       
  1074   }
       
  1075 
       
  1076   // Klass pointers to object array klasses need some flattening
       
  1077   const TypeKlassPtr *tk = tj->isa_klassptr();
       
  1078   if( tk ) {
       
  1079     // If we are referencing a field within a Klass, we need
       
  1080     // to assume the worst case of an Object.  Both exact and
       
  1081     // inexact types must flatten to the same alias class.
       
  1082     // Since the flattened result for a klass is defined to be
       
  1083     // precisely java.lang.Object, use a constant ptr.
       
  1084     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
       
  1085 
       
  1086       tj = tk = TypeKlassPtr::make(TypePtr::Constant,
       
  1087                                    TypeKlassPtr::OBJECT->klass(),
       
  1088                                    offset);
       
  1089     }
       
  1090 
       
  1091     ciKlass* klass = tk->klass();
       
  1092     if( klass->is_obj_array_klass() ) {
       
  1093       ciKlass* k = TypeAryPtr::OOPS->klass();
       
  1094       if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
       
  1095         k = TypeInstPtr::BOTTOM->klass();
       
  1096       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
       
  1097     }
       
  1098 
       
  1099     // Check for precise loads from the primary supertype array and force them
       
  1100     // to the supertype cache alias index.  Check for generic array loads from
       
  1101     // the primary supertype array and also force them to the supertype cache
       
  1102     // alias index.  Since the same load can reach both, we need to merge
       
  1103     // these 2 disparate memories into the same alias class.  Since the
       
  1104     // primary supertype array is read-only, there's no chance of confusion
       
  1105     // where we bypass an array load and an array store.
       
  1106     uint off2 = offset - Klass::primary_supers_offset_in_bytes();
       
  1107     if( offset == Type::OffsetBot ||
       
  1108         off2 < Klass::primary_super_limit()*wordSize ) {
       
  1109       offset = sizeof(oopDesc) +Klass::secondary_super_cache_offset_in_bytes();
       
  1110       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
       
  1111     }
       
  1112   }
       
  1113 
       
  1114   // Flatten all Raw pointers together.
       
  1115   if (tj->base() == Type::RawPtr)
       
  1116     tj = TypeRawPtr::BOTTOM;
       
  1117 
       
  1118   if (tj->base() == Type::AnyPtr)
       
  1119     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
       
  1120 
       
  1121   // Flatten all to bottom for now
       
  1122   switch( _AliasLevel ) {
       
  1123   case 0:
       
  1124     tj = TypePtr::BOTTOM;
       
  1125     break;
       
  1126   case 1:                       // Flatten to: oop, static, field or array
       
  1127     switch (tj->base()) {
       
  1128     //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
       
  1129     case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
       
  1130     case Type::AryPtr:   // do not distinguish arrays at all
       
  1131     case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
       
  1132     case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
       
  1133     case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
       
  1134     default: ShouldNotReachHere();
       
  1135     }
       
  1136     break;
       
  1137   case 2:                       // No collasping at level 2; keep all splits
       
  1138   case 3:                       // No collasping at level 3; keep all splits
       
  1139     break;
       
  1140   default:
       
  1141     Unimplemented();
       
  1142   }
       
  1143 
       
  1144   offset = tj->offset();
       
  1145   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
       
  1146 
       
  1147   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
       
  1148           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
       
  1149           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
       
  1150           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
       
  1151           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
       
  1152           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
       
  1153           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr)  ,
       
  1154           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
       
  1155   assert( tj->ptr() != TypePtr::TopPTR &&
       
  1156           tj->ptr() != TypePtr::AnyNull &&
       
  1157           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
       
  1158 //    assert( tj->ptr() != TypePtr::Constant ||
       
  1159 //            tj->base() == Type::RawPtr ||
       
  1160 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
       
  1161 
       
  1162   return tj;
       
  1163 }
       
  1164 
       
  1165 void Compile::AliasType::Init(int i, const TypePtr* at) {
       
  1166   _index = i;
       
  1167   _adr_type = at;
       
  1168   _field = NULL;
       
  1169   _is_rewritable = true; // default
       
  1170   const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
       
  1171   if (atoop != NULL && atoop->is_instance()) {
       
  1172     const TypeOopPtr *gt = atoop->cast_to_instance(TypeOopPtr::UNKNOWN_INSTANCE);
       
  1173     _general_index = Compile::current()->get_alias_index(gt);
       
  1174   } else {
       
  1175     _general_index = 0;
       
  1176   }
       
  1177 }
       
  1178 
       
  1179 //---------------------------------print_on------------------------------------
       
  1180 #ifndef PRODUCT
       
  1181 void Compile::AliasType::print_on(outputStream* st) {
       
  1182   if (index() < 10)
       
  1183         st->print("@ <%d> ", index());
       
  1184   else  st->print("@ <%d>",  index());
       
  1185   st->print(is_rewritable() ? "   " : " RO");
       
  1186   int offset = adr_type()->offset();
       
  1187   if (offset == Type::OffsetBot)
       
  1188         st->print(" +any");
       
  1189   else  st->print(" +%-3d", offset);
       
  1190   st->print(" in ");
       
  1191   adr_type()->dump_on(st);
       
  1192   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
       
  1193   if (field() != NULL && tjp) {
       
  1194     if (tjp->klass()  != field()->holder() ||
       
  1195         tjp->offset() != field()->offset_in_bytes()) {
       
  1196       st->print(" != ");
       
  1197       field()->print();
       
  1198       st->print(" ***");
       
  1199     }
       
  1200   }
       
  1201 }
       
  1202 
       
  1203 void print_alias_types() {
       
  1204   Compile* C = Compile::current();
       
  1205   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
       
  1206   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
       
  1207     C->alias_type(idx)->print_on(tty);
       
  1208     tty->cr();
       
  1209   }
       
  1210 }
       
  1211 #endif
       
  1212 
       
  1213 
       
  1214 //----------------------------probe_alias_cache--------------------------------
       
  1215 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
       
  1216   intptr_t key = (intptr_t) adr_type;
       
  1217   key ^= key >> logAliasCacheSize;
       
  1218   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
       
  1219 }
       
  1220 
       
  1221 
       
  1222 //-----------------------------grow_alias_types--------------------------------
       
  1223 void Compile::grow_alias_types() {
       
  1224   const int old_ats  = _max_alias_types; // how many before?
       
  1225   const int new_ats  = old_ats;          // how many more?
       
  1226   const int grow_ats = old_ats+new_ats;  // how many now?
       
  1227   _max_alias_types = grow_ats;
       
  1228   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
       
  1229   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
       
  1230   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
       
  1231   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
       
  1232 }
       
  1233 
       
  1234 
       
  1235 //--------------------------------find_alias_type------------------------------
       
  1236 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create) {
       
  1237   if (_AliasLevel == 0)
       
  1238     return alias_type(AliasIdxBot);
       
  1239 
       
  1240   AliasCacheEntry* ace = probe_alias_cache(adr_type);
       
  1241   if (ace->_adr_type == adr_type) {
       
  1242     return alias_type(ace->_index);
       
  1243   }
       
  1244 
       
  1245   // Handle special cases.
       
  1246   if (adr_type == NULL)             return alias_type(AliasIdxTop);
       
  1247   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
       
  1248 
       
  1249   // Do it the slow way.
       
  1250   const TypePtr* flat = flatten_alias_type(adr_type);
       
  1251 
       
  1252 #ifdef ASSERT
       
  1253   assert(flat == flatten_alias_type(flat), "idempotent");
       
  1254   assert(flat != TypePtr::BOTTOM,     "cannot alias-analyze an untyped ptr");
       
  1255   if (flat->isa_oopptr() && !flat->isa_klassptr()) {
       
  1256     const TypeOopPtr* foop = flat->is_oopptr();
       
  1257     const TypePtr* xoop = foop->cast_to_exactness(!foop->klass_is_exact())->is_ptr();
       
  1258     assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type");
       
  1259   }
       
  1260   assert(flat == flatten_alias_type(flat), "exact bit doesn't matter");
       
  1261 #endif
       
  1262 
       
  1263   int idx = AliasIdxTop;
       
  1264   for (int i = 0; i < num_alias_types(); i++) {
       
  1265     if (alias_type(i)->adr_type() == flat) {
       
  1266       idx = i;
       
  1267       break;
       
  1268     }
       
  1269   }
       
  1270 
       
  1271   if (idx == AliasIdxTop) {
       
  1272     if (no_create)  return NULL;
       
  1273     // Grow the array if necessary.
       
  1274     if (_num_alias_types == _max_alias_types)  grow_alias_types();
       
  1275     // Add a new alias type.
       
  1276     idx = _num_alias_types++;
       
  1277     _alias_types[idx]->Init(idx, flat);
       
  1278     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
       
  1279     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
       
  1280     if (flat->isa_instptr()) {
       
  1281       if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
       
  1282           && flat->is_instptr()->klass() == env()->Class_klass())
       
  1283         alias_type(idx)->set_rewritable(false);
       
  1284     }
       
  1285     if (flat->isa_klassptr()) {
       
  1286       if (flat->offset() == Klass::super_check_offset_offset_in_bytes() + (int)sizeof(oopDesc))
       
  1287         alias_type(idx)->set_rewritable(false);
       
  1288       if (flat->offset() == Klass::modifier_flags_offset_in_bytes() + (int)sizeof(oopDesc))
       
  1289         alias_type(idx)->set_rewritable(false);
       
  1290       if (flat->offset() == Klass::access_flags_offset_in_bytes() + (int)sizeof(oopDesc))
       
  1291         alias_type(idx)->set_rewritable(false);
       
  1292       if (flat->offset() == Klass::java_mirror_offset_in_bytes() + (int)sizeof(oopDesc))
       
  1293         alias_type(idx)->set_rewritable(false);
       
  1294     }
       
  1295     // %%% (We would like to finalize JavaThread::threadObj_offset(),
       
  1296     // but the base pointer type is not distinctive enough to identify
       
  1297     // references into JavaThread.)
       
  1298 
       
  1299     // Check for final instance fields.
       
  1300     const TypeInstPtr* tinst = flat->isa_instptr();
       
  1301     if (tinst && tinst->offset() >= oopDesc::header_size() * wordSize) {
       
  1302       ciInstanceKlass *k = tinst->klass()->as_instance_klass();
       
  1303       ciField* field = k->get_field_by_offset(tinst->offset(), false);
       
  1304       // Set field() and is_rewritable() attributes.
       
  1305       if (field != NULL)  alias_type(idx)->set_field(field);
       
  1306     }
       
  1307     const TypeKlassPtr* tklass = flat->isa_klassptr();
       
  1308     // Check for final static fields.
       
  1309     if (tklass && tklass->klass()->is_instance_klass()) {
       
  1310       ciInstanceKlass *k = tklass->klass()->as_instance_klass();
       
  1311       ciField* field = k->get_field_by_offset(tklass->offset(), true);
       
  1312       // Set field() and is_rewritable() attributes.
       
  1313       if (field != NULL)   alias_type(idx)->set_field(field);
       
  1314     }
       
  1315   }
       
  1316 
       
  1317   // Fill the cache for next time.
       
  1318   ace->_adr_type = adr_type;
       
  1319   ace->_index    = idx;
       
  1320   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
       
  1321 
       
  1322   // Might as well try to fill the cache for the flattened version, too.
       
  1323   AliasCacheEntry* face = probe_alias_cache(flat);
       
  1324   if (face->_adr_type == NULL) {
       
  1325     face->_adr_type = flat;
       
  1326     face->_index    = idx;
       
  1327     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
       
  1328   }
       
  1329 
       
  1330   return alias_type(idx);
       
  1331 }
       
  1332 
       
  1333 
       
  1334 Compile::AliasType* Compile::alias_type(ciField* field) {
       
  1335   const TypeOopPtr* t;
       
  1336   if (field->is_static())
       
  1337     t = TypeKlassPtr::make(field->holder());
       
  1338   else
       
  1339     t = TypeOopPtr::make_from_klass_raw(field->holder());
       
  1340   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()));
       
  1341   assert(field->is_final() == !atp->is_rewritable(), "must get the rewritable bits correct");
       
  1342   return atp;
       
  1343 }
       
  1344 
       
  1345 
       
  1346 //------------------------------have_alias_type--------------------------------
       
  1347 bool Compile::have_alias_type(const TypePtr* adr_type) {
       
  1348   AliasCacheEntry* ace = probe_alias_cache(adr_type);
       
  1349   if (ace->_adr_type == adr_type) {
       
  1350     return true;
       
  1351   }
       
  1352 
       
  1353   // Handle special cases.
       
  1354   if (adr_type == NULL)             return true;
       
  1355   if (adr_type == TypePtr::BOTTOM)  return true;
       
  1356 
       
  1357   return find_alias_type(adr_type, true) != NULL;
       
  1358 }
       
  1359 
       
  1360 //-----------------------------must_alias--------------------------------------
       
  1361 // True if all values of the given address type are in the given alias category.
       
  1362 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
       
  1363   if (alias_idx == AliasIdxBot)         return true;  // the universal category
       
  1364   if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
       
  1365   if (alias_idx == AliasIdxTop)         return false; // the empty category
       
  1366   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
       
  1367 
       
  1368   // the only remaining possible overlap is identity
       
  1369   int adr_idx = get_alias_index(adr_type);
       
  1370   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
       
  1371   assert(adr_idx == alias_idx ||
       
  1372          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
       
  1373           && adr_type                       != TypeOopPtr::BOTTOM),
       
  1374          "should not be testing for overlap with an unsafe pointer");
       
  1375   return adr_idx == alias_idx;
       
  1376 }
       
  1377 
       
  1378 //------------------------------can_alias--------------------------------------
       
  1379 // True if any values of the given address type are in the given alias category.
       
  1380 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
       
  1381   if (alias_idx == AliasIdxTop)         return false; // the empty category
       
  1382   if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
       
  1383   if (alias_idx == AliasIdxBot)         return true;  // the universal category
       
  1384   if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
       
  1385 
       
  1386   // the only remaining possible overlap is identity
       
  1387   int adr_idx = get_alias_index(adr_type);
       
  1388   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
       
  1389   return adr_idx == alias_idx;
       
  1390 }
       
  1391 
       
  1392 
       
  1393 
       
  1394 //---------------------------pop_warm_call-------------------------------------
       
  1395 WarmCallInfo* Compile::pop_warm_call() {
       
  1396   WarmCallInfo* wci = _warm_calls;
       
  1397   if (wci != NULL)  _warm_calls = wci->remove_from(wci);
       
  1398   return wci;
       
  1399 }
       
  1400 
       
  1401 //----------------------------Inline_Warm--------------------------------------
       
  1402 int Compile::Inline_Warm() {
       
  1403   // If there is room, try to inline some more warm call sites.
       
  1404   // %%% Do a graph index compaction pass when we think we're out of space?
       
  1405   if (!InlineWarmCalls)  return 0;
       
  1406 
       
  1407   int calls_made_hot = 0;
       
  1408   int room_to_grow   = NodeCountInliningCutoff - unique();
       
  1409   int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
       
  1410   int amount_grown   = 0;
       
  1411   WarmCallInfo* call;
       
  1412   while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
       
  1413     int est_size = (int)call->size();
       
  1414     if (est_size > (room_to_grow - amount_grown)) {
       
  1415       // This one won't fit anyway.  Get rid of it.
       
  1416       call->make_cold();
       
  1417       continue;
       
  1418     }
       
  1419     call->make_hot();
       
  1420     calls_made_hot++;
       
  1421     amount_grown   += est_size;
       
  1422     amount_to_grow -= est_size;
       
  1423   }
       
  1424 
       
  1425   if (calls_made_hot > 0)  set_major_progress();
       
  1426   return calls_made_hot;
       
  1427 }
       
  1428 
       
  1429 
       
  1430 //----------------------------Finish_Warm--------------------------------------
       
  1431 void Compile::Finish_Warm() {
       
  1432   if (!InlineWarmCalls)  return;
       
  1433   if (failing())  return;
       
  1434   if (warm_calls() == NULL)  return;
       
  1435 
       
  1436   // Clean up loose ends, if we are out of space for inlining.
       
  1437   WarmCallInfo* call;
       
  1438   while ((call = pop_warm_call()) != NULL) {
       
  1439     call->make_cold();
       
  1440   }
       
  1441 }
       
  1442 
       
  1443 
       
  1444 //------------------------------Optimize---------------------------------------
       
  1445 // Given a graph, optimize it.
       
  1446 void Compile::Optimize() {
       
  1447   TracePhase t1("optimizer", &_t_optimizer, true);
       
  1448 
       
  1449 #ifndef PRODUCT
       
  1450   if (env()->break_at_compile()) {
       
  1451     BREAKPOINT;
       
  1452   }
       
  1453 
       
  1454 #endif
       
  1455 
       
  1456   ResourceMark rm;
       
  1457   int          loop_opts_cnt;
       
  1458 
       
  1459   NOT_PRODUCT( verify_graph_edges(); )
       
  1460 
       
  1461   print_method("Start");
       
  1462 
       
  1463  {
       
  1464   // Iterative Global Value Numbering, including ideal transforms
       
  1465   // Initialize IterGVN with types and values from parse-time GVN
       
  1466   PhaseIterGVN igvn(initial_gvn());
       
  1467   {
       
  1468     NOT_PRODUCT( TracePhase t2("iterGVN", &_t_iterGVN, TimeCompiler); )
       
  1469     igvn.optimize();
       
  1470   }
       
  1471 
       
  1472   print_method("Iter GVN 1", 2);
       
  1473 
       
  1474   if (failing())  return;
       
  1475 
       
  1476   // get rid of the connection graph since it's information is not
       
  1477   // updated by optimizations
       
  1478   _congraph = NULL;
       
  1479 
       
  1480 
       
  1481   // Loop transforms on the ideal graph.  Range Check Elimination,
       
  1482   // peeling, unrolling, etc.
       
  1483 
       
  1484   // Set loop opts counter
       
  1485   loop_opts_cnt = num_loop_opts();
       
  1486   if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
       
  1487     {
       
  1488       TracePhase t2("idealLoop", &_t_idealLoop, true);
       
  1489       PhaseIdealLoop ideal_loop( igvn, NULL, true );
       
  1490       loop_opts_cnt--;
       
  1491       if (major_progress()) print_method("PhaseIdealLoop 1", 2);
       
  1492       if (failing())  return;
       
  1493     }
       
  1494     // Loop opts pass if partial peeling occurred in previous pass
       
  1495     if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
       
  1496       TracePhase t3("idealLoop", &_t_idealLoop, true);
       
  1497       PhaseIdealLoop ideal_loop( igvn, NULL, false );
       
  1498       loop_opts_cnt--;
       
  1499       if (major_progress()) print_method("PhaseIdealLoop 2", 2);
       
  1500       if (failing())  return;
       
  1501     }
       
  1502     // Loop opts pass for loop-unrolling before CCP
       
  1503     if(major_progress() && (loop_opts_cnt > 0)) {
       
  1504       TracePhase t4("idealLoop", &_t_idealLoop, true);
       
  1505       PhaseIdealLoop ideal_loop( igvn, NULL, false );
       
  1506       loop_opts_cnt--;
       
  1507       if (major_progress()) print_method("PhaseIdealLoop 3", 2);
       
  1508     }
       
  1509   }
       
  1510   if (failing())  return;
       
  1511 
       
  1512   // Conditional Constant Propagation;
       
  1513   PhaseCCP ccp( &igvn );
       
  1514   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
       
  1515   {
       
  1516     TracePhase t2("ccp", &_t_ccp, true);
       
  1517     ccp.do_transform();
       
  1518   }
       
  1519   print_method("PhaseCPP 1", 2);
       
  1520 
       
  1521   assert( true, "Break here to ccp.dump_old2new_map()");
       
  1522 
       
  1523   // Iterative Global Value Numbering, including ideal transforms
       
  1524   {
       
  1525     NOT_PRODUCT( TracePhase t2("iterGVN2", &_t_iterGVN2, TimeCompiler); )
       
  1526     igvn = ccp;
       
  1527     igvn.optimize();
       
  1528   }
       
  1529 
       
  1530   print_method("Iter GVN 2", 2);
       
  1531 
       
  1532   if (failing())  return;
       
  1533 
       
  1534   // Loop transforms on the ideal graph.  Range Check Elimination,
       
  1535   // peeling, unrolling, etc.
       
  1536   if(loop_opts_cnt > 0) {
       
  1537     debug_only( int cnt = 0; );
       
  1538     while(major_progress() && (loop_opts_cnt > 0)) {
       
  1539       TracePhase t2("idealLoop", &_t_idealLoop, true);
       
  1540       assert( cnt++ < 40, "infinite cycle in loop optimization" );
       
  1541       PhaseIdealLoop ideal_loop( igvn, NULL, true );
       
  1542       loop_opts_cnt--;
       
  1543       if (major_progress()) print_method("PhaseIdealLoop iterations", 2);
       
  1544       if (failing())  return;
       
  1545     }
       
  1546   }
       
  1547   {
       
  1548     NOT_PRODUCT( TracePhase t2("macroExpand", &_t_macroExpand, TimeCompiler); )
       
  1549     PhaseMacroExpand  mex(igvn);
       
  1550     if (mex.expand_macro_nodes()) {
       
  1551       assert(failing(), "must bail out w/ explicit message");
       
  1552       return;
       
  1553     }
       
  1554   }
       
  1555 
       
  1556  } // (End scope of igvn; run destructor if necessary for asserts.)
       
  1557 
       
  1558   // A method with only infinite loops has no edges entering loops from root
       
  1559   {
       
  1560     NOT_PRODUCT( TracePhase t2("graphReshape", &_t_graphReshaping, TimeCompiler); )
       
  1561     if (final_graph_reshaping()) {
       
  1562       assert(failing(), "must bail out w/ explicit message");
       
  1563       return;
       
  1564     }
       
  1565   }
       
  1566 
       
  1567   print_method("Optimize finished", 2);
       
  1568 }
       
  1569 
       
  1570 
       
  1571 //------------------------------Code_Gen---------------------------------------
       
  1572 // Given a graph, generate code for it
       
  1573 void Compile::Code_Gen() {
       
  1574   if (failing())  return;
       
  1575 
       
  1576   // Perform instruction selection.  You might think we could reclaim Matcher
       
  1577   // memory PDQ, but actually the Matcher is used in generating spill code.
       
  1578   // Internals of the Matcher (including some VectorSets) must remain live
       
  1579   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
       
  1580   // set a bit in reclaimed memory.
       
  1581 
       
  1582   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
       
  1583   // nodes.  Mapping is only valid at the root of each matched subtree.
       
  1584   NOT_PRODUCT( verify_graph_edges(); )
       
  1585 
       
  1586   Node_List proj_list;
       
  1587   Matcher m(proj_list);
       
  1588   _matcher = &m;
       
  1589   {
       
  1590     TracePhase t2("matcher", &_t_matcher, true);
       
  1591     m.match();
       
  1592   }
       
  1593   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
       
  1594   // nodes.  Mapping is only valid at the root of each matched subtree.
       
  1595   NOT_PRODUCT( verify_graph_edges(); )
       
  1596 
       
  1597   // If you have too many nodes, or if matching has failed, bail out
       
  1598   check_node_count(0, "out of nodes matching instructions");
       
  1599   if (failing())  return;
       
  1600 
       
  1601   // Build a proper-looking CFG
       
  1602   PhaseCFG cfg(node_arena(), root(), m);
       
  1603   _cfg = &cfg;
       
  1604   {
       
  1605     NOT_PRODUCT( TracePhase t2("scheduler", &_t_scheduler, TimeCompiler); )
       
  1606     cfg.Dominators();
       
  1607     if (failing())  return;
       
  1608 
       
  1609     NOT_PRODUCT( verify_graph_edges(); )
       
  1610 
       
  1611     cfg.Estimate_Block_Frequency();
       
  1612     cfg.GlobalCodeMotion(m,unique(),proj_list);
       
  1613 
       
  1614     print_method("Global code motion", 2);
       
  1615 
       
  1616     if (failing())  return;
       
  1617     NOT_PRODUCT( verify_graph_edges(); )
       
  1618 
       
  1619     debug_only( cfg.verify(); )
       
  1620   }
       
  1621   NOT_PRODUCT( verify_graph_edges(); )
       
  1622 
       
  1623   PhaseChaitin regalloc(unique(),cfg,m);
       
  1624   _regalloc = &regalloc;
       
  1625   {
       
  1626     TracePhase t2("regalloc", &_t_registerAllocation, true);
       
  1627     // Perform any platform dependent preallocation actions.  This is used,
       
  1628     // for example, to avoid taking an implicit null pointer exception
       
  1629     // using the frame pointer on win95.
       
  1630     _regalloc->pd_preallocate_hook();
       
  1631 
       
  1632     // Perform register allocation.  After Chaitin, use-def chains are
       
  1633     // no longer accurate (at spill code) and so must be ignored.
       
  1634     // Node->LRG->reg mappings are still accurate.
       
  1635     _regalloc->Register_Allocate();
       
  1636 
       
  1637     // Bail out if the allocator builds too many nodes
       
  1638     if (failing())  return;
       
  1639   }
       
  1640 
       
  1641   // Prior to register allocation we kept empty basic blocks in case the
       
  1642   // the allocator needed a place to spill.  After register allocation we
       
  1643   // are not adding any new instructions.  If any basic block is empty, we
       
  1644   // can now safely remove it.
       
  1645   {
       
  1646     NOT_PRODUCT( TracePhase t2("removeEmpty", &_t_removeEmptyBlocks, TimeCompiler); )
       
  1647     cfg.RemoveEmpty();
       
  1648   }
       
  1649 
       
  1650   // Perform any platform dependent postallocation verifications.
       
  1651   debug_only( _regalloc->pd_postallocate_verify_hook(); )
       
  1652 
       
  1653   // Apply peephole optimizations
       
  1654   if( OptoPeephole ) {
       
  1655     NOT_PRODUCT( TracePhase t2("peephole", &_t_peephole, TimeCompiler); )
       
  1656     PhasePeephole peep( _regalloc, cfg);
       
  1657     peep.do_transform();
       
  1658   }
       
  1659 
       
  1660   // Convert Nodes to instruction bits in a buffer
       
  1661   {
       
  1662     // %%%% workspace merge brought two timers together for one job
       
  1663     TracePhase t2a("output", &_t_output, true);
       
  1664     NOT_PRODUCT( TraceTime t2b(NULL, &_t_codeGeneration, TimeCompiler, false); )
       
  1665     Output();
       
  1666   }
       
  1667 
       
  1668   print_method("End");
       
  1669 
       
  1670   // He's dead, Jim.
       
  1671   _cfg     = (PhaseCFG*)0xdeadbeef;
       
  1672   _regalloc = (PhaseChaitin*)0xdeadbeef;
       
  1673 }
       
  1674 
       
  1675 
       
  1676 //------------------------------dump_asm---------------------------------------
       
  1677 // Dump formatted assembly
       
  1678 #ifndef PRODUCT
       
  1679 void Compile::dump_asm(int *pcs, uint pc_limit) {
       
  1680   bool cut_short = false;
       
  1681   tty->print_cr("#");
       
  1682   tty->print("#  ");  _tf->dump();  tty->cr();
       
  1683   tty->print_cr("#");
       
  1684 
       
  1685   // For all blocks
       
  1686   int pc = 0x0;                 // Program counter
       
  1687   char starts_bundle = ' ';
       
  1688   _regalloc->dump_frame();
       
  1689 
       
  1690   Node *n = NULL;
       
  1691   for( uint i=0; i<_cfg->_num_blocks; i++ ) {
       
  1692     if (VMThread::should_terminate()) { cut_short = true; break; }
       
  1693     Block *b = _cfg->_blocks[i];
       
  1694     if (b->is_connector() && !Verbose) continue;
       
  1695     n = b->_nodes[0];
       
  1696     if (pcs && n->_idx < pc_limit)
       
  1697       tty->print("%3.3x   ", pcs[n->_idx]);
       
  1698     else
       
  1699       tty->print("      ");
       
  1700     b->dump_head( &_cfg->_bbs );
       
  1701     if (b->is_connector()) {
       
  1702       tty->print_cr("        # Empty connector block");
       
  1703     } else if (b->num_preds() == 2 && b->pred(1)->is_CatchProj() && b->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
       
  1704       tty->print_cr("        # Block is sole successor of call");
       
  1705     }
       
  1706 
       
  1707     // For all instructions
       
  1708     Node *delay = NULL;
       
  1709     for( uint j = 0; j<b->_nodes.size(); j++ ) {
       
  1710       if (VMThread::should_terminate()) { cut_short = true; break; }
       
  1711       n = b->_nodes[j];
       
  1712       if (valid_bundle_info(n)) {
       
  1713         Bundle *bundle = node_bundling(n);
       
  1714         if (bundle->used_in_unconditional_delay()) {
       
  1715           delay = n;
       
  1716           continue;
       
  1717         }
       
  1718         if (bundle->starts_bundle())
       
  1719           starts_bundle = '+';
       
  1720       }
       
  1721 
       
  1722       if( !n->is_Region() &&    // Dont print in the Assembly
       
  1723           !n->is_Phi() &&       // a few noisely useless nodes
       
  1724           !n->is_Proj() &&
       
  1725           !n->is_MachTemp() &&
       
  1726           !n->is_Catch() &&     // Would be nice to print exception table targets
       
  1727           !n->is_MergeMem() &&  // Not very interesting
       
  1728           !n->is_top() &&       // Debug info table constants
       
  1729           !(n->is_Con() && !n->is_Mach())// Debug info table constants
       
  1730           ) {
       
  1731         if (pcs && n->_idx < pc_limit)
       
  1732           tty->print("%3.3x", pcs[n->_idx]);
       
  1733         else
       
  1734           tty->print("   ");
       
  1735         tty->print(" %c ", starts_bundle);
       
  1736         starts_bundle = ' ';
       
  1737         tty->print("\t");
       
  1738         n->format(_regalloc, tty);
       
  1739         tty->cr();
       
  1740       }
       
  1741 
       
  1742       // If we have an instruction with a delay slot, and have seen a delay,
       
  1743       // then back up and print it
       
  1744       if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
       
  1745         assert(delay != NULL, "no unconditional delay instruction");
       
  1746         if (node_bundling(delay)->starts_bundle())
       
  1747           starts_bundle = '+';
       
  1748         if (pcs && n->_idx < pc_limit)
       
  1749           tty->print("%3.3x", pcs[n->_idx]);
       
  1750         else
       
  1751           tty->print("   ");
       
  1752         tty->print(" %c ", starts_bundle);
       
  1753         starts_bundle = ' ';
       
  1754         tty->print("\t");
       
  1755         delay->format(_regalloc, tty);
       
  1756         tty->print_cr("");
       
  1757         delay = NULL;
       
  1758       }
       
  1759 
       
  1760       // Dump the exception table as well
       
  1761       if( n->is_Catch() && (Verbose || WizardMode) ) {
       
  1762         // Print the exception table for this offset
       
  1763         _handler_table.print_subtable_for(pc);
       
  1764       }
       
  1765     }
       
  1766 
       
  1767     if (pcs && n->_idx < pc_limit)
       
  1768       tty->print_cr("%3.3x", pcs[n->_idx]);
       
  1769     else
       
  1770       tty->print_cr("");
       
  1771 
       
  1772     assert(cut_short || delay == NULL, "no unconditional delay branch");
       
  1773 
       
  1774   } // End of per-block dump
       
  1775   tty->print_cr("");
       
  1776 
       
  1777   if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
       
  1778 }
       
  1779 #endif
       
  1780 
       
  1781 //------------------------------Final_Reshape_Counts---------------------------
       
  1782 // This class defines counters to help identify when a method
       
  1783 // may/must be executed using hardware with only 24-bit precision.
       
  1784 struct Final_Reshape_Counts : public StackObj {
       
  1785   int  _call_count;             // count non-inlined 'common' calls
       
  1786   int  _float_count;            // count float ops requiring 24-bit precision
       
  1787   int  _double_count;           // count double ops requiring more precision
       
  1788   int  _java_call_count;        // count non-inlined 'java' calls
       
  1789   VectorSet _visited;           // Visitation flags
       
  1790   Node_List _tests;             // Set of IfNodes & PCTableNodes
       
  1791 
       
  1792   Final_Reshape_Counts() :
       
  1793     _call_count(0), _float_count(0), _double_count(0), _java_call_count(0),
       
  1794     _visited( Thread::current()->resource_area() ) { }
       
  1795 
       
  1796   void inc_call_count  () { _call_count  ++; }
       
  1797   void inc_float_count () { _float_count ++; }
       
  1798   void inc_double_count() { _double_count++; }
       
  1799   void inc_java_call_count() { _java_call_count++; }
       
  1800 
       
  1801   int  get_call_count  () const { return _call_count  ; }
       
  1802   int  get_float_count () const { return _float_count ; }
       
  1803   int  get_double_count() const { return _double_count; }
       
  1804   int  get_java_call_count() const { return _java_call_count; }
       
  1805 };
       
  1806 
       
  1807 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
       
  1808   ciInstanceKlass *k = tp->klass()->as_instance_klass();
       
  1809   // Make sure the offset goes inside the instance layout.
       
  1810   return (uint)tp->offset() < (uint)(oopDesc::header_size() + k->nonstatic_field_size())*wordSize;
       
  1811   // Note that OffsetBot and OffsetTop are very negative.
       
  1812 }
       
  1813 
       
  1814 //------------------------------final_graph_reshaping_impl----------------------
       
  1815 // Implement items 1-5 from final_graph_reshaping below.
       
  1816 static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &fpu ) {
       
  1817 
       
  1818   uint nop = n->Opcode();
       
  1819 
       
  1820   // Check for 2-input instruction with "last use" on right input.
       
  1821   // Swap to left input.  Implements item (2).
       
  1822   if( n->req() == 3 &&          // two-input instruction
       
  1823       n->in(1)->outcnt() > 1 && // left use is NOT a last use
       
  1824       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
       
  1825       n->in(2)->outcnt() == 1 &&// right use IS a last use
       
  1826       !n->in(2)->is_Con() ) {   // right use is not a constant
       
  1827     // Check for commutative opcode
       
  1828     switch( nop ) {
       
  1829     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
       
  1830     case Op_MaxI:  case Op_MinI:
       
  1831     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
       
  1832     case Op_AndL:  case Op_XorL:  case Op_OrL:
       
  1833     case Op_AndI:  case Op_XorI:  case Op_OrI: {
       
  1834       // Move "last use" input to left by swapping inputs
       
  1835       n->swap_edges(1, 2);
       
  1836       break;
       
  1837     }
       
  1838     default:
       
  1839       break;
       
  1840     }
       
  1841   }
       
  1842 
       
  1843   // Count FPU ops and common calls, implements item (3)
       
  1844   switch( nop ) {
       
  1845   // Count all float operations that may use FPU
       
  1846   case Op_AddF:
       
  1847   case Op_SubF:
       
  1848   case Op_MulF:
       
  1849   case Op_DivF:
       
  1850   case Op_NegF:
       
  1851   case Op_ModF:
       
  1852   case Op_ConvI2F:
       
  1853   case Op_ConF:
       
  1854   case Op_CmpF:
       
  1855   case Op_CmpF3:
       
  1856   // case Op_ConvL2F: // longs are split into 32-bit halves
       
  1857     fpu.inc_float_count();
       
  1858     break;
       
  1859 
       
  1860   case Op_ConvF2D:
       
  1861   case Op_ConvD2F:
       
  1862     fpu.inc_float_count();
       
  1863     fpu.inc_double_count();
       
  1864     break;
       
  1865 
       
  1866   // Count all double operations that may use FPU
       
  1867   case Op_AddD:
       
  1868   case Op_SubD:
       
  1869   case Op_MulD:
       
  1870   case Op_DivD:
       
  1871   case Op_NegD:
       
  1872   case Op_ModD:
       
  1873   case Op_ConvI2D:
       
  1874   case Op_ConvD2I:
       
  1875   // case Op_ConvL2D: // handled by leaf call
       
  1876   // case Op_ConvD2L: // handled by leaf call
       
  1877   case Op_ConD:
       
  1878   case Op_CmpD:
       
  1879   case Op_CmpD3:
       
  1880     fpu.inc_double_count();
       
  1881     break;
       
  1882   case Op_Opaque1:              // Remove Opaque Nodes before matching
       
  1883   case Op_Opaque2:              // Remove Opaque Nodes before matching
       
  1884     n->replace_by(n->in(1));
       
  1885     break;
       
  1886   case Op_CallStaticJava:
       
  1887   case Op_CallJava:
       
  1888   case Op_CallDynamicJava:
       
  1889     fpu.inc_java_call_count(); // Count java call site;
       
  1890   case Op_CallRuntime:
       
  1891   case Op_CallLeaf:
       
  1892   case Op_CallLeafNoFP: {
       
  1893     assert( n->is_Call(), "" );
       
  1894     CallNode *call = n->as_Call();
       
  1895     // Count call sites where the FP mode bit would have to be flipped.
       
  1896     // Do not count uncommon runtime calls:
       
  1897     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
       
  1898     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
       
  1899     if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
       
  1900       fpu.inc_call_count();   // Count the call site
       
  1901     } else {                  // See if uncommon argument is shared
       
  1902       Node *n = call->in(TypeFunc::Parms);
       
  1903       int nop = n->Opcode();
       
  1904       // Clone shared simple arguments to uncommon calls, item (1).
       
  1905       if( n->outcnt() > 1 &&
       
  1906           !n->is_Proj() &&
       
  1907           nop != Op_CreateEx &&
       
  1908           nop != Op_CheckCastPP &&
       
  1909           !n->is_Mem() ) {
       
  1910         Node *x = n->clone();
       
  1911         call->set_req( TypeFunc::Parms, x );
       
  1912       }
       
  1913     }
       
  1914     break;
       
  1915   }
       
  1916 
       
  1917   case Op_StoreD:
       
  1918   case Op_LoadD:
       
  1919   case Op_LoadD_unaligned:
       
  1920     fpu.inc_double_count();
       
  1921     goto handle_mem;
       
  1922   case Op_StoreF:
       
  1923   case Op_LoadF:
       
  1924     fpu.inc_float_count();
       
  1925     goto handle_mem;
       
  1926 
       
  1927   case Op_StoreB:
       
  1928   case Op_StoreC:
       
  1929   case Op_StoreCM:
       
  1930   case Op_StorePConditional:
       
  1931   case Op_StoreI:
       
  1932   case Op_StoreL:
       
  1933   case Op_StoreLConditional:
       
  1934   case Op_CompareAndSwapI:
       
  1935   case Op_CompareAndSwapL:
       
  1936   case Op_CompareAndSwapP:
       
  1937   case Op_StoreP:
       
  1938   case Op_LoadB:
       
  1939   case Op_LoadC:
       
  1940   case Op_LoadI:
       
  1941   case Op_LoadKlass:
       
  1942   case Op_LoadL:
       
  1943   case Op_LoadL_unaligned:
       
  1944   case Op_LoadPLocked:
       
  1945   case Op_LoadLLocked:
       
  1946   case Op_LoadP:
       
  1947   case Op_LoadRange:
       
  1948   case Op_LoadS: {
       
  1949   handle_mem:
       
  1950 #ifdef ASSERT
       
  1951     if( VerifyOptoOopOffsets ) {
       
  1952       assert( n->is_Mem(), "" );
       
  1953       MemNode *mem  = (MemNode*)n;
       
  1954       // Check to see if address types have grounded out somehow.
       
  1955       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
       
  1956       assert( !tp || oop_offset_is_sane(tp), "" );
       
  1957     }
       
  1958 #endif
       
  1959     break;
       
  1960   }
       
  1961   case Op_If:
       
  1962   case Op_CountedLoopEnd:
       
  1963     fpu._tests.push(n);         // Collect CFG split points
       
  1964     break;
       
  1965 
       
  1966   case Op_AddP: {               // Assert sane base pointers
       
  1967     const Node *addp = n->in(AddPNode::Address);
       
  1968     assert( !addp->is_AddP() ||
       
  1969             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
       
  1970             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
       
  1971             "Base pointers must match" );
       
  1972     break;
       
  1973   }
       
  1974 
       
  1975   case Op_ModI:
       
  1976     if (UseDivMod) {
       
  1977       // Check if a%b and a/b both exist
       
  1978       Node* d = n->find_similar(Op_DivI);
       
  1979       if (d) {
       
  1980         // Replace them with a fused divmod if supported
       
  1981         Compile* C = Compile::current();
       
  1982         if (Matcher::has_match_rule(Op_DivModI)) {
       
  1983           DivModINode* divmod = DivModINode::make(C, n);
       
  1984           d->replace_by(divmod->div_proj());
       
  1985           n->replace_by(divmod->mod_proj());
       
  1986         } else {
       
  1987           // replace a%b with a-((a/b)*b)
       
  1988           Node* mult = new (C, 3) MulINode(d, d->in(2));
       
  1989           Node* sub  = new (C, 3) SubINode(d->in(1), mult);
       
  1990           n->replace_by( sub );
       
  1991         }
       
  1992       }
       
  1993     }
       
  1994     break;
       
  1995 
       
  1996   case Op_ModL:
       
  1997     if (UseDivMod) {
       
  1998       // Check if a%b and a/b both exist
       
  1999       Node* d = n->find_similar(Op_DivL);
       
  2000       if (d) {
       
  2001         // Replace them with a fused divmod if supported
       
  2002         Compile* C = Compile::current();
       
  2003         if (Matcher::has_match_rule(Op_DivModL)) {
       
  2004           DivModLNode* divmod = DivModLNode::make(C, n);
       
  2005           d->replace_by(divmod->div_proj());
       
  2006           n->replace_by(divmod->mod_proj());
       
  2007         } else {
       
  2008           // replace a%b with a-((a/b)*b)
       
  2009           Node* mult = new (C, 3) MulLNode(d, d->in(2));
       
  2010           Node* sub  = new (C, 3) SubLNode(d->in(1), mult);
       
  2011           n->replace_by( sub );
       
  2012         }
       
  2013       }
       
  2014     }
       
  2015     break;
       
  2016 
       
  2017   case Op_Load16B:
       
  2018   case Op_Load8B:
       
  2019   case Op_Load4B:
       
  2020   case Op_Load8S:
       
  2021   case Op_Load4S:
       
  2022   case Op_Load2S:
       
  2023   case Op_Load8C:
       
  2024   case Op_Load4C:
       
  2025   case Op_Load2C:
       
  2026   case Op_Load4I:
       
  2027   case Op_Load2I:
       
  2028   case Op_Load2L:
       
  2029   case Op_Load4F:
       
  2030   case Op_Load2F:
       
  2031   case Op_Load2D:
       
  2032   case Op_Store16B:
       
  2033   case Op_Store8B:
       
  2034   case Op_Store4B:
       
  2035   case Op_Store8C:
       
  2036   case Op_Store4C:
       
  2037   case Op_Store2C:
       
  2038   case Op_Store4I:
       
  2039   case Op_Store2I:
       
  2040   case Op_Store2L:
       
  2041   case Op_Store4F:
       
  2042   case Op_Store2F:
       
  2043   case Op_Store2D:
       
  2044     break;
       
  2045 
       
  2046   case Op_PackB:
       
  2047   case Op_PackS:
       
  2048   case Op_PackC:
       
  2049   case Op_PackI:
       
  2050   case Op_PackF:
       
  2051   case Op_PackL:
       
  2052   case Op_PackD:
       
  2053     if (n->req()-1 > 2) {
       
  2054       // Replace many operand PackNodes with a binary tree for matching
       
  2055       PackNode* p = (PackNode*) n;
       
  2056       Node* btp = p->binaryTreePack(Compile::current(), 1, n->req());
       
  2057       n->replace_by(btp);
       
  2058     }
       
  2059     break;
       
  2060   default:
       
  2061     assert( !n->is_Call(), "" );
       
  2062     assert( !n->is_Mem(), "" );
       
  2063     if( n->is_If() || n->is_PCTable() )
       
  2064       fpu._tests.push(n);       // Collect CFG split points
       
  2065     break;
       
  2066   }
       
  2067 }
       
  2068 
       
  2069 //------------------------------final_graph_reshaping_walk---------------------
       
  2070 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
       
  2071 // requires that the walk visits a node's inputs before visiting the node.
       
  2072 static void final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &fpu ) {
       
  2073   fpu._visited.set(root->_idx); // first, mark node as visited
       
  2074   uint cnt = root->req();
       
  2075   Node *n = root;
       
  2076   uint  i = 0;
       
  2077   while (true) {
       
  2078     if (i < cnt) {
       
  2079       // Place all non-visited non-null inputs onto stack
       
  2080       Node* m = n->in(i);
       
  2081       ++i;
       
  2082       if (m != NULL && !fpu._visited.test_set(m->_idx)) {
       
  2083         cnt = m->req();
       
  2084         nstack.push(n, i); // put on stack parent and next input's index
       
  2085         n = m;
       
  2086         i = 0;
       
  2087       }
       
  2088     } else {
       
  2089       // Now do post-visit work
       
  2090       final_graph_reshaping_impl( n, fpu );
       
  2091       if (nstack.is_empty())
       
  2092         break;             // finished
       
  2093       n = nstack.node();   // Get node from stack
       
  2094       cnt = n->req();
       
  2095       i = nstack.index();
       
  2096       nstack.pop();        // Shift to the next node on stack
       
  2097     }
       
  2098   }
       
  2099 }
       
  2100 
       
  2101 //------------------------------final_graph_reshaping--------------------------
       
  2102 // Final Graph Reshaping.
       
  2103 //
       
  2104 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
       
  2105 //     and not commoned up and forced early.  Must come after regular
       
  2106 //     optimizations to avoid GVN undoing the cloning.  Clone constant
       
  2107 //     inputs to Loop Phis; these will be split by the allocator anyways.
       
  2108 //     Remove Opaque nodes.
       
  2109 // (2) Move last-uses by commutative operations to the left input to encourage
       
  2110 //     Intel update-in-place two-address operations and better register usage
       
  2111 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
       
  2112 //     calls canonicalizing them back.
       
  2113 // (3) Count the number of double-precision FP ops, single-precision FP ops
       
  2114 //     and call sites.  On Intel, we can get correct rounding either by
       
  2115 //     forcing singles to memory (requires extra stores and loads after each
       
  2116 //     FP bytecode) or we can set a rounding mode bit (requires setting and
       
  2117 //     clearing the mode bit around call sites).  The mode bit is only used
       
  2118 //     if the relative frequency of single FP ops to calls is low enough.
       
  2119 //     This is a key transform for SPEC mpeg_audio.
       
  2120 // (4) Detect infinite loops; blobs of code reachable from above but not
       
  2121 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
       
  2122 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
       
  2123 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
       
  2124 //     Detection is by looking for IfNodes where only 1 projection is
       
  2125 //     reachable from below or CatchNodes missing some targets.
       
  2126 // (5) Assert for insane oop offsets in debug mode.
       
  2127 
       
  2128 bool Compile::final_graph_reshaping() {
       
  2129   // an infinite loop may have been eliminated by the optimizer,
       
  2130   // in which case the graph will be empty.
       
  2131   if (root()->req() == 1) {
       
  2132     record_method_not_compilable("trivial infinite loop");
       
  2133     return true;
       
  2134   }
       
  2135 
       
  2136   Final_Reshape_Counts fpu;
       
  2137 
       
  2138   // Visit everybody reachable!
       
  2139   // Allocate stack of size C->unique()/2 to avoid frequent realloc
       
  2140   Node_Stack nstack(unique() >> 1);
       
  2141   final_graph_reshaping_walk(nstack, root(), fpu);
       
  2142 
       
  2143   // Check for unreachable (from below) code (i.e., infinite loops).
       
  2144   for( uint i = 0; i < fpu._tests.size(); i++ ) {
       
  2145     Node *n = fpu._tests[i];
       
  2146     assert( n->is_PCTable() || n->is_If(), "either PCTables or IfNodes" );
       
  2147     // Get number of CFG targets; 2 for IfNodes or _size for PCTables.
       
  2148     // Note that PCTables include exception targets after calls.
       
  2149     uint expected_kids = n->is_PCTable() ? n->as_PCTable()->_size : 2;
       
  2150     if (n->outcnt() != expected_kids) {
       
  2151       // Check for a few special cases.  Rethrow Nodes never take the
       
  2152       // 'fall-thru' path, so expected kids is 1 less.
       
  2153       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
       
  2154         if (n->in(0)->in(0)->is_Call()) {
       
  2155           CallNode *call = n->in(0)->in(0)->as_Call();
       
  2156           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
       
  2157             expected_kids--;      // Rethrow always has 1 less kid
       
  2158           } else if (call->req() > TypeFunc::Parms &&
       
  2159                      call->is_CallDynamicJava()) {
       
  2160             // Check for null receiver. In such case, the optimizer has
       
  2161             // detected that the virtual call will always result in a null
       
  2162             // pointer exception. The fall-through projection of this CatchNode
       
  2163             // will not be populated.
       
  2164             Node *arg0 = call->in(TypeFunc::Parms);
       
  2165             if (arg0->is_Type() &&
       
  2166                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
       
  2167               expected_kids--;
       
  2168             }
       
  2169           } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
       
  2170                      call->req() > TypeFunc::Parms+1 &&
       
  2171                      call->is_CallStaticJava()) {
       
  2172             // Check for negative array length. In such case, the optimizer has
       
  2173             // detected that the allocation attempt will always result in an
       
  2174             // exception. There is no fall-through projection of this CatchNode .
       
  2175             Node *arg1 = call->in(TypeFunc::Parms+1);
       
  2176             if (arg1->is_Type() &&
       
  2177                 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
       
  2178               expected_kids--;
       
  2179             }
       
  2180           }
       
  2181         }
       
  2182       }
       
  2183       // Recheck with a better notion of 'expected_kids'
       
  2184       if (n->outcnt() != expected_kids) {
       
  2185         record_method_not_compilable("malformed control flow");
       
  2186         return true;            // Not all targets reachable!
       
  2187       }
       
  2188     }
       
  2189     // Check that I actually visited all kids.  Unreached kids
       
  2190     // must be infinite loops.
       
  2191     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
       
  2192       if (!fpu._visited.test(n->fast_out(j)->_idx)) {
       
  2193         record_method_not_compilable("infinite loop");
       
  2194         return true;            // Found unvisited kid; must be unreach
       
  2195       }
       
  2196   }
       
  2197 
       
  2198   // If original bytecodes contained a mixture of floats and doubles
       
  2199   // check if the optimizer has made it homogenous, item (3).
       
  2200   if( Use24BitFPMode && Use24BitFP &&
       
  2201       fpu.get_float_count() > 32 &&
       
  2202       fpu.get_double_count() == 0 &&
       
  2203       (10 * fpu.get_call_count() < fpu.get_float_count()) ) {
       
  2204     set_24_bit_selection_and_mode( false,  true );
       
  2205   }
       
  2206 
       
  2207   set_has_java_calls(fpu.get_java_call_count() > 0);
       
  2208 
       
  2209   // No infinite loops, no reason to bail out.
       
  2210   return false;
       
  2211 }
       
  2212 
       
  2213 //-----------------------------too_many_traps----------------------------------
       
  2214 // Report if there are too many traps at the current method and bci.
       
  2215 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
       
  2216 bool Compile::too_many_traps(ciMethod* method,
       
  2217                              int bci,
       
  2218                              Deoptimization::DeoptReason reason) {
       
  2219   ciMethodData* md = method->method_data();
       
  2220   if (md->is_empty()) {
       
  2221     // Assume the trap has not occurred, or that it occurred only
       
  2222     // because of a transient condition during start-up in the interpreter.
       
  2223     return false;
       
  2224   }
       
  2225   if (md->has_trap_at(bci, reason) != 0) {
       
  2226     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
       
  2227     // Also, if there are multiple reasons, or if there is no per-BCI record,
       
  2228     // assume the worst.
       
  2229     if (log())
       
  2230       log()->elem("observe trap='%s' count='%d'",
       
  2231                   Deoptimization::trap_reason_name(reason),
       
  2232                   md->trap_count(reason));
       
  2233     return true;
       
  2234   } else {
       
  2235     // Ignore method/bci and see if there have been too many globally.
       
  2236     return too_many_traps(reason, md);
       
  2237   }
       
  2238 }
       
  2239 
       
  2240 // Less-accurate variant which does not require a method and bci.
       
  2241 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
       
  2242                              ciMethodData* logmd) {
       
  2243  if (trap_count(reason) >= (uint)PerMethodTrapLimit) {
       
  2244     // Too many traps globally.
       
  2245     // Note that we use cumulative trap_count, not just md->trap_count.
       
  2246     if (log()) {
       
  2247       int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
       
  2248       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
       
  2249                   Deoptimization::trap_reason_name(reason),
       
  2250                   mcount, trap_count(reason));
       
  2251     }
       
  2252     return true;
       
  2253   } else {
       
  2254     // The coast is clear.
       
  2255     return false;
       
  2256   }
       
  2257 }
       
  2258 
       
  2259 //--------------------------too_many_recompiles--------------------------------
       
  2260 // Report if there are too many recompiles at the current method and bci.
       
  2261 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
       
  2262 // Is not eager to return true, since this will cause the compiler to use
       
  2263 // Action_none for a trap point, to avoid too many recompilations.
       
  2264 bool Compile::too_many_recompiles(ciMethod* method,
       
  2265                                   int bci,
       
  2266                                   Deoptimization::DeoptReason reason) {
       
  2267   ciMethodData* md = method->method_data();
       
  2268   if (md->is_empty()) {
       
  2269     // Assume the trap has not occurred, or that it occurred only
       
  2270     // because of a transient condition during start-up in the interpreter.
       
  2271     return false;
       
  2272   }
       
  2273   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
       
  2274   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
       
  2275   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
       
  2276   Deoptimization::DeoptReason per_bc_reason
       
  2277     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
       
  2278   if ((per_bc_reason == Deoptimization::Reason_none
       
  2279        || md->has_trap_at(bci, reason) != 0)
       
  2280       // The trap frequency measure we care about is the recompile count:
       
  2281       && md->trap_recompiled_at(bci)
       
  2282       && md->overflow_recompile_count() >= bc_cutoff) {
       
  2283     // Do not emit a trap here if it has already caused recompilations.
       
  2284     // Also, if there are multiple reasons, or if there is no per-BCI record,
       
  2285     // assume the worst.
       
  2286     if (log())
       
  2287       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
       
  2288                   Deoptimization::trap_reason_name(reason),
       
  2289                   md->trap_count(reason),
       
  2290                   md->overflow_recompile_count());
       
  2291     return true;
       
  2292   } else if (trap_count(reason) != 0
       
  2293              && decompile_count() >= m_cutoff) {
       
  2294     // Too many recompiles globally, and we have seen this sort of trap.
       
  2295     // Use cumulative decompile_count, not just md->decompile_count.
       
  2296     if (log())
       
  2297       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
       
  2298                   Deoptimization::trap_reason_name(reason),
       
  2299                   md->trap_count(reason), trap_count(reason),
       
  2300                   md->decompile_count(), decompile_count());
       
  2301     return true;
       
  2302   } else {
       
  2303     // The coast is clear.
       
  2304     return false;
       
  2305   }
       
  2306 }
       
  2307 
       
  2308 
       
  2309 #ifndef PRODUCT
       
  2310 //------------------------------verify_graph_edges---------------------------
       
  2311 // Walk the Graph and verify that there is a one-to-one correspondence
       
  2312 // between Use-Def edges and Def-Use edges in the graph.
       
  2313 void Compile::verify_graph_edges(bool no_dead_code) {
       
  2314   if (VerifyGraphEdges) {
       
  2315     ResourceArea *area = Thread::current()->resource_area();
       
  2316     Unique_Node_List visited(area);
       
  2317     // Call recursive graph walk to check edges
       
  2318     _root->verify_edges(visited);
       
  2319     if (no_dead_code) {
       
  2320       // Now make sure that no visited node is used by an unvisited node.
       
  2321       bool dead_nodes = 0;
       
  2322       Unique_Node_List checked(area);
       
  2323       while (visited.size() > 0) {
       
  2324         Node* n = visited.pop();
       
  2325         checked.push(n);
       
  2326         for (uint i = 0; i < n->outcnt(); i++) {
       
  2327           Node* use = n->raw_out(i);
       
  2328           if (checked.member(use))  continue;  // already checked
       
  2329           if (visited.member(use))  continue;  // already in the graph
       
  2330           if (use->is_Con())        continue;  // a dead ConNode is OK
       
  2331           // At this point, we have found a dead node which is DU-reachable.
       
  2332           if (dead_nodes++ == 0)
       
  2333             tty->print_cr("*** Dead nodes reachable via DU edges:");
       
  2334           use->dump(2);
       
  2335           tty->print_cr("---");
       
  2336           checked.push(use);  // No repeats; pretend it is now checked.
       
  2337         }
       
  2338       }
       
  2339       assert(dead_nodes == 0, "using nodes must be reachable from root");
       
  2340     }
       
  2341   }
       
  2342 }
       
  2343 #endif
       
  2344 
       
  2345 // The Compile object keeps track of failure reasons separately from the ciEnv.
       
  2346 // This is required because there is not quite a 1-1 relation between the
       
  2347 // ciEnv and its compilation task and the Compile object.  Note that one
       
  2348 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
       
  2349 // to backtrack and retry without subsuming loads.  Other than this backtracking
       
  2350 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
       
  2351 // by the logic in C2Compiler.
       
  2352 void Compile::record_failure(const char* reason) {
       
  2353   if (log() != NULL) {
       
  2354     log()->elem("failure reason='%s' phase='compile'", reason);
       
  2355   }
       
  2356   if (_failure_reason == NULL) {
       
  2357     // Record the first failure reason.
       
  2358     _failure_reason = reason;
       
  2359   }
       
  2360   _root = NULL;  // flush the graph, too
       
  2361 }
       
  2362 
       
  2363 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator, bool dolog)
       
  2364   : TraceTime(NULL, accumulator, false NOT_PRODUCT( || TimeCompiler ), false)
       
  2365 {
       
  2366   if (dolog) {
       
  2367     C = Compile::current();
       
  2368     _log = C->log();
       
  2369   } else {
       
  2370     C = NULL;
       
  2371     _log = NULL;
       
  2372   }
       
  2373   if (_log != NULL) {
       
  2374     _log->begin_head("phase name='%s' nodes='%d'", name, C->unique());
       
  2375     _log->stamp();
       
  2376     _log->end_head();
       
  2377   }
       
  2378 }
       
  2379 
       
  2380 Compile::TracePhase::~TracePhase() {
       
  2381   if (_log != NULL) {
       
  2382     _log->done("phase nodes='%d'", C->unique());
       
  2383   }
       
  2384 }