src/share/vm/opto/compile.cpp

Fri, 08 Apr 2011 14:19:50 -0700

author
jmasa
date
Fri, 08 Apr 2011 14:19:50 -0700
changeset 2784
92add02409c9
parent 2683
7e88bdae86ec
parent 2781
e1162778c1c8
child 2787
5d046bf49ce7
permissions
-rw-r--r--

Merge

     1 /*
     2  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.
     8  *
     9  * This code is distributed in the hope that it will be useful, but WITHOUT
    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    12  * version 2 for more details (a copy is included in the LICENSE file that
    13  * accompanied this code).
    14  *
    15  * You should have received a copy of the GNU General Public License version
    16  * 2 along with this work; if not, write to the Free Software Foundation,
    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    18  *
    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    20  * or visit www.oracle.com if you need additional information or have any
    21  * questions.
    22  *
    23  */
    25 #include "precompiled.hpp"
    26 #include "asm/assembler.hpp"
    27 #include "classfile/systemDictionary.hpp"
    28 #include "code/exceptionHandlerTable.hpp"
    29 #include "code/nmethod.hpp"
    30 #include "compiler/compileLog.hpp"
    31 #include "compiler/oopMap.hpp"
    32 #include "opto/addnode.hpp"
    33 #include "opto/block.hpp"
    34 #include "opto/c2compiler.hpp"
    35 #include "opto/callGenerator.hpp"
    36 #include "opto/callnode.hpp"
    37 #include "opto/cfgnode.hpp"
    38 #include "opto/chaitin.hpp"
    39 #include "opto/compile.hpp"
    40 #include "opto/connode.hpp"
    41 #include "opto/divnode.hpp"
    42 #include "opto/escape.hpp"
    43 #include "opto/idealGraphPrinter.hpp"
    44 #include "opto/loopnode.hpp"
    45 #include "opto/machnode.hpp"
    46 #include "opto/macro.hpp"
    47 #include "opto/matcher.hpp"
    48 #include "opto/memnode.hpp"
    49 #include "opto/mulnode.hpp"
    50 #include "opto/node.hpp"
    51 #include "opto/opcodes.hpp"
    52 #include "opto/output.hpp"
    53 #include "opto/parse.hpp"
    54 #include "opto/phaseX.hpp"
    55 #include "opto/rootnode.hpp"
    56 #include "opto/runtime.hpp"
    57 #include "opto/stringopts.hpp"
    58 #include "opto/type.hpp"
    59 #include "opto/vectornode.hpp"
    60 #include "runtime/arguments.hpp"
    61 #include "runtime/signature.hpp"
    62 #include "runtime/stubRoutines.hpp"
    63 #include "runtime/timer.hpp"
    64 #include "utilities/copy.hpp"
    65 #ifdef TARGET_ARCH_MODEL_x86_32
    66 # include "adfiles/ad_x86_32.hpp"
    67 #endif
    68 #ifdef TARGET_ARCH_MODEL_x86_64
    69 # include "adfiles/ad_x86_64.hpp"
    70 #endif
    71 #ifdef TARGET_ARCH_MODEL_sparc
    72 # include "adfiles/ad_sparc.hpp"
    73 #endif
    74 #ifdef TARGET_ARCH_MODEL_zero
    75 # include "adfiles/ad_zero.hpp"
    76 #endif
    77 #ifdef TARGET_ARCH_MODEL_arm
    78 # include "adfiles/ad_arm.hpp"
    79 #endif
    80 #ifdef TARGET_ARCH_MODEL_ppc
    81 # include "adfiles/ad_ppc.hpp"
    82 #endif
    85 // -------------------- Compile::mach_constant_base_node -----------------------
    86 // Constant table base node singleton.
    87 MachConstantBaseNode* Compile::mach_constant_base_node() {
    88   if (_mach_constant_base_node == NULL) {
    89     _mach_constant_base_node = new (C) MachConstantBaseNode();
    90     _mach_constant_base_node->add_req(C->root());
    91   }
    92   return _mach_constant_base_node;
    93 }
    96 /// Support for intrinsics.
    98 // Return the index at which m must be inserted (or already exists).
    99 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
   100 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual) {
   101 #ifdef ASSERT
   102   for (int i = 1; i < _intrinsics->length(); i++) {
   103     CallGenerator* cg1 = _intrinsics->at(i-1);
   104     CallGenerator* cg2 = _intrinsics->at(i);
   105     assert(cg1->method() != cg2->method()
   106            ? cg1->method()     < cg2->method()
   107            : cg1->is_virtual() < cg2->is_virtual(),
   108            "compiler intrinsics list must stay sorted");
   109   }
   110 #endif
   111   // Binary search sorted list, in decreasing intervals [lo, hi].
   112   int lo = 0, hi = _intrinsics->length()-1;
   113   while (lo <= hi) {
   114     int mid = (uint)(hi + lo) / 2;
   115     ciMethod* mid_m = _intrinsics->at(mid)->method();
   116     if (m < mid_m) {
   117       hi = mid-1;
   118     } else if (m > mid_m) {
   119       lo = mid+1;
   120     } else {
   121       // look at minor sort key
   122       bool mid_virt = _intrinsics->at(mid)->is_virtual();
   123       if (is_virtual < mid_virt) {
   124         hi = mid-1;
   125       } else if (is_virtual > mid_virt) {
   126         lo = mid+1;
   127       } else {
   128         return mid;  // exact match
   129       }
   130     }
   131   }
   132   return lo;  // inexact match
   133 }
   135 void Compile::register_intrinsic(CallGenerator* cg) {
   136   if (_intrinsics == NULL) {
   137     _intrinsics = new GrowableArray<CallGenerator*>(60);
   138   }
   139   // This code is stolen from ciObjectFactory::insert.
   140   // Really, GrowableArray should have methods for
   141   // insert_at, remove_at, and binary_search.
   142   int len = _intrinsics->length();
   143   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual());
   144   if (index == len) {
   145     _intrinsics->append(cg);
   146   } else {
   147 #ifdef ASSERT
   148     CallGenerator* oldcg = _intrinsics->at(index);
   149     assert(oldcg->method() != cg->method() || oldcg->is_virtual() != cg->is_virtual(), "don't register twice");
   150 #endif
   151     _intrinsics->append(_intrinsics->at(len-1));
   152     int pos;
   153     for (pos = len-2; pos >= index; pos--) {
   154       _intrinsics->at_put(pos+1,_intrinsics->at(pos));
   155     }
   156     _intrinsics->at_put(index, cg);
   157   }
   158   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
   159 }
   161 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
   162   assert(m->is_loaded(), "don't try this on unloaded methods");
   163   if (_intrinsics != NULL) {
   164     int index = intrinsic_insertion_index(m, is_virtual);
   165     if (index < _intrinsics->length()
   166         && _intrinsics->at(index)->method() == m
   167         && _intrinsics->at(index)->is_virtual() == is_virtual) {
   168       return _intrinsics->at(index);
   169     }
   170   }
   171   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
   172   if (m->intrinsic_id() != vmIntrinsics::_none &&
   173       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
   174     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
   175     if (cg != NULL) {
   176       // Save it for next time:
   177       register_intrinsic(cg);
   178       return cg;
   179     } else {
   180       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
   181     }
   182   }
   183   return NULL;
   184 }
   186 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
   187 // in library_call.cpp.
   190 #ifndef PRODUCT
   191 // statistics gathering...
   193 juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
   194 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
   196 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
   197   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
   198   int oflags = _intrinsic_hist_flags[id];
   199   assert(flags != 0, "what happened?");
   200   if (is_virtual) {
   201     flags |= _intrinsic_virtual;
   202   }
   203   bool changed = (flags != oflags);
   204   if ((flags & _intrinsic_worked) != 0) {
   205     juint count = (_intrinsic_hist_count[id] += 1);
   206     if (count == 1) {
   207       changed = true;           // first time
   208     }
   209     // increment the overall count also:
   210     _intrinsic_hist_count[vmIntrinsics::_none] += 1;
   211   }
   212   if (changed) {
   213     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
   214       // Something changed about the intrinsic's virtuality.
   215       if ((flags & _intrinsic_virtual) != 0) {
   216         // This is the first use of this intrinsic as a virtual call.
   217         if (oflags != 0) {
   218           // We already saw it as a non-virtual, so note both cases.
   219           flags |= _intrinsic_both;
   220         }
   221       } else if ((oflags & _intrinsic_both) == 0) {
   222         // This is the first use of this intrinsic as a non-virtual
   223         flags |= _intrinsic_both;
   224       }
   225     }
   226     _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
   227   }
   228   // update the overall flags also:
   229   _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
   230   return changed;
   231 }
   233 static char* format_flags(int flags, char* buf) {
   234   buf[0] = 0;
   235   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
   236   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
   237   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
   238   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
   239   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
   240   if (buf[0] == 0)  strcat(buf, ",");
   241   assert(buf[0] == ',', "must be");
   242   return &buf[1];
   243 }
   245 void Compile::print_intrinsic_statistics() {
   246   char flagsbuf[100];
   247   ttyLocker ttyl;
   248   if (xtty != NULL)  xtty->head("statistics type='intrinsic'");
   249   tty->print_cr("Compiler intrinsic usage:");
   250   juint total = _intrinsic_hist_count[vmIntrinsics::_none];
   251   if (total == 0)  total = 1;  // avoid div0 in case of no successes
   252   #define PRINT_STAT_LINE(name, c, f) \
   253     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
   254   for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
   255     vmIntrinsics::ID id = (vmIntrinsics::ID) index;
   256     int   flags = _intrinsic_hist_flags[id];
   257     juint count = _intrinsic_hist_count[id];
   258     if ((flags | count) != 0) {
   259       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
   260     }
   261   }
   262   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
   263   if (xtty != NULL)  xtty->tail("statistics");
   264 }
   266 void Compile::print_statistics() {
   267   { ttyLocker ttyl;
   268     if (xtty != NULL)  xtty->head("statistics type='opto'");
   269     Parse::print_statistics();
   270     PhaseCCP::print_statistics();
   271     PhaseRegAlloc::print_statistics();
   272     Scheduling::print_statistics();
   273     PhasePeephole::print_statistics();
   274     PhaseIdealLoop::print_statistics();
   275     if (xtty != NULL)  xtty->tail("statistics");
   276   }
   277   if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
   278     // put this under its own <statistics> element.
   279     print_intrinsic_statistics();
   280   }
   281 }
   282 #endif //PRODUCT
   284 // Support for bundling info
   285 Bundle* Compile::node_bundling(const Node *n) {
   286   assert(valid_bundle_info(n), "oob");
   287   return &_node_bundling_base[n->_idx];
   288 }
   290 bool Compile::valid_bundle_info(const Node *n) {
   291   return (_node_bundling_limit > n->_idx);
   292 }
   295 void Compile::gvn_replace_by(Node* n, Node* nn) {
   296   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
   297     Node* use = n->last_out(i);
   298     bool is_in_table = initial_gvn()->hash_delete(use);
   299     uint uses_found = 0;
   300     for (uint j = 0; j < use->len(); j++) {
   301       if (use->in(j) == n) {
   302         if (j < use->req())
   303           use->set_req(j, nn);
   304         else
   305           use->set_prec(j, nn);
   306         uses_found++;
   307       }
   308     }
   309     if (is_in_table) {
   310       // reinsert into table
   311       initial_gvn()->hash_find_insert(use);
   312     }
   313     record_for_igvn(use);
   314     i -= uses_found;    // we deleted 1 or more copies of this edge
   315   }
   316 }
   321 // Identify all nodes that are reachable from below, useful.
   322 // Use breadth-first pass that records state in a Unique_Node_List,
   323 // recursive traversal is slower.
   324 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
   325   int estimated_worklist_size = unique();
   326   useful.map( estimated_worklist_size, NULL );  // preallocate space
   328   // Initialize worklist
   329   if (root() != NULL)     { useful.push(root()); }
   330   // If 'top' is cached, declare it useful to preserve cached node
   331   if( cached_top_node() ) { useful.push(cached_top_node()); }
   333   // Push all useful nodes onto the list, breadthfirst
   334   for( uint next = 0; next < useful.size(); ++next ) {
   335     assert( next < unique(), "Unique useful nodes < total nodes");
   336     Node *n  = useful.at(next);
   337     uint max = n->len();
   338     for( uint i = 0; i < max; ++i ) {
   339       Node *m = n->in(i);
   340       if( m == NULL ) continue;
   341       useful.push(m);
   342     }
   343   }
   344 }
   346 // Disconnect all useless nodes by disconnecting those at the boundary.
   347 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
   348   uint next = 0;
   349   while( next < useful.size() ) {
   350     Node *n = useful.at(next++);
   351     // Use raw traversal of out edges since this code removes out edges
   352     int max = n->outcnt();
   353     for (int j = 0; j < max; ++j ) {
   354       Node* child = n->raw_out(j);
   355       if( ! useful.member(child) ) {
   356         assert( !child->is_top() || child != top(),
   357                 "If top is cached in Compile object it is in useful list");
   358         // Only need to remove this out-edge to the useless node
   359         n->raw_del_out(j);
   360         --j;
   361         --max;
   362       }
   363     }
   364     if (n->outcnt() == 1 && n->has_special_unique_user()) {
   365       record_for_igvn( n->unique_out() );
   366     }
   367   }
   368   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
   369 }
   371 //------------------------------frame_size_in_words-----------------------------
   372 // frame_slots in units of words
   373 int Compile::frame_size_in_words() const {
   374   // shift is 0 in LP32 and 1 in LP64
   375   const int shift = (LogBytesPerWord - LogBytesPerInt);
   376   int words = _frame_slots >> shift;
   377   assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
   378   return words;
   379 }
   381 // ============================================================================
   382 //------------------------------CompileWrapper---------------------------------
   383 class CompileWrapper : public StackObj {
   384   Compile *const _compile;
   385  public:
   386   CompileWrapper(Compile* compile);
   388   ~CompileWrapper();
   389 };
   391 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
   392   // the Compile* pointer is stored in the current ciEnv:
   393   ciEnv* env = compile->env();
   394   assert(env == ciEnv::current(), "must already be a ciEnv active");
   395   assert(env->compiler_data() == NULL, "compile already active?");
   396   env->set_compiler_data(compile);
   397   assert(compile == Compile::current(), "sanity");
   399   compile->set_type_dict(NULL);
   400   compile->set_type_hwm(NULL);
   401   compile->set_type_last_size(0);
   402   compile->set_last_tf(NULL, NULL);
   403   compile->set_indexSet_arena(NULL);
   404   compile->set_indexSet_free_block_list(NULL);
   405   compile->init_type_arena();
   406   Type::Initialize(compile);
   407   _compile->set_scratch_buffer_blob(NULL);
   408   _compile->begin_method();
   409 }
   410 CompileWrapper::~CompileWrapper() {
   411   _compile->end_method();
   412   if (_compile->scratch_buffer_blob() != NULL)
   413     BufferBlob::free(_compile->scratch_buffer_blob());
   414   _compile->env()->set_compiler_data(NULL);
   415 }
   418 //----------------------------print_compile_messages---------------------------
   419 void Compile::print_compile_messages() {
   420 #ifndef PRODUCT
   421   // Check if recompiling
   422   if (_subsume_loads == false && PrintOpto) {
   423     // Recompiling without allowing machine instructions to subsume loads
   424     tty->print_cr("*********************************************************");
   425     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
   426     tty->print_cr("*********************************************************");
   427   }
   428   if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
   429     // Recompiling without escape analysis
   430     tty->print_cr("*********************************************************");
   431     tty->print_cr("** Bailout: Recompile without escape analysis          **");
   432     tty->print_cr("*********************************************************");
   433   }
   434   if (env()->break_at_compile()) {
   435     // Open the debugger when compiling this method.
   436     tty->print("### Breaking when compiling: ");
   437     method()->print_short_name();
   438     tty->cr();
   439     BREAKPOINT;
   440   }
   442   if( PrintOpto ) {
   443     if (is_osr_compilation()) {
   444       tty->print("[OSR]%3d", _compile_id);
   445     } else {
   446       tty->print("%3d", _compile_id);
   447     }
   448   }
   449 #endif
   450 }
   453 //-----------------------init_scratch_buffer_blob------------------------------
   454 // Construct a temporary BufferBlob and cache it for this compile.
   455 void Compile::init_scratch_buffer_blob(int const_size) {
   456   // If there is already a scratch buffer blob allocated and the
   457   // constant section is big enough, use it.  Otherwise free the
   458   // current and allocate a new one.
   459   BufferBlob* blob = scratch_buffer_blob();
   460   if ((blob != NULL) && (const_size <= _scratch_const_size)) {
   461     // Use the current blob.
   462   } else {
   463     if (blob != NULL) {
   464       BufferBlob::free(blob);
   465     }
   467     ResourceMark rm;
   468     _scratch_const_size = const_size;
   469     int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
   470     blob = BufferBlob::create("Compile::scratch_buffer", size);
   471     // Record the buffer blob for next time.
   472     set_scratch_buffer_blob(blob);
   473     // Have we run out of code space?
   474     if (scratch_buffer_blob() == NULL) {
   475       // Let CompilerBroker disable further compilations.
   476       record_failure("Not enough space for scratch buffer in CodeCache");
   477       return;
   478     }
   479   }
   481   // Initialize the relocation buffers
   482   relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
   483   set_scratch_locs_memory(locs_buf);
   484 }
   487 //-----------------------scratch_emit_size-------------------------------------
   488 // Helper function that computes size by emitting code
   489 uint Compile::scratch_emit_size(const Node* n) {
   490   // Start scratch_emit_size section.
   491   set_in_scratch_emit_size(true);
   493   // Emit into a trash buffer and count bytes emitted.
   494   // This is a pretty expensive way to compute a size,
   495   // but it works well enough if seldom used.
   496   // All common fixed-size instructions are given a size
   497   // method by the AD file.
   498   // Note that the scratch buffer blob and locs memory are
   499   // allocated at the beginning of the compile task, and
   500   // may be shared by several calls to scratch_emit_size.
   501   // The allocation of the scratch buffer blob is particularly
   502   // expensive, since it has to grab the code cache lock.
   503   BufferBlob* blob = this->scratch_buffer_blob();
   504   assert(blob != NULL, "Initialize BufferBlob at start");
   505   assert(blob->size() > MAX_inst_size, "sanity");
   506   relocInfo* locs_buf = scratch_locs_memory();
   507   address blob_begin = blob->content_begin();
   508   address blob_end   = (address)locs_buf;
   509   assert(blob->content_contains(blob_end), "sanity");
   510   CodeBuffer buf(blob_begin, blob_end - blob_begin);
   511   buf.initialize_consts_size(_scratch_const_size);
   512   buf.initialize_stubs_size(MAX_stubs_size);
   513   assert(locs_buf != NULL, "sanity");
   514   int lsize = MAX_locs_size / 3;
   515   buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
   516   buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
   517   buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
   519   // Do the emission.
   520   n->emit(buf, this->regalloc());
   522   // End scratch_emit_size section.
   523   set_in_scratch_emit_size(false);
   525   return buf.insts_size();
   526 }
   529 // ============================================================================
   530 //------------------------------Compile standard-------------------------------
   531 debug_only( int Compile::_debug_idx = 100000; )
   533 // Compile a method.  entry_bci is -1 for normal compilations and indicates
   534 // the continuation bci for on stack replacement.
   537 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci, bool subsume_loads, bool do_escape_analysis )
   538                 : Phase(Compiler),
   539                   _env(ci_env),
   540                   _log(ci_env->log()),
   541                   _compile_id(ci_env->compile_id()),
   542                   _save_argument_registers(false),
   543                   _stub_name(NULL),
   544                   _stub_function(NULL),
   545                   _stub_entry_point(NULL),
   546                   _method(target),
   547                   _entry_bci(osr_bci),
   548                   _initial_gvn(NULL),
   549                   _for_igvn(NULL),
   550                   _warm_calls(NULL),
   551                   _subsume_loads(subsume_loads),
   552                   _do_escape_analysis(do_escape_analysis),
   553                   _failure_reason(NULL),
   554                   _code_buffer("Compile::Fill_buffer"),
   555                   _orig_pc_slot(0),
   556                   _orig_pc_slot_offset_in_bytes(0),
   557                   _has_method_handle_invokes(false),
   558                   _mach_constant_base_node(NULL),
   559                   _node_bundling_limit(0),
   560                   _node_bundling_base(NULL),
   561                   _java_calls(0),
   562                   _inner_loops(0),
   563                   _scratch_const_size(-1),
   564                   _in_scratch_emit_size(false),
   565 #ifndef PRODUCT
   566                   _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
   567                   _printer(IdealGraphPrinter::printer()),
   568 #endif
   569                   _congraph(NULL) {
   570   C = this;
   572   CompileWrapper cw(this);
   573 #ifndef PRODUCT
   574   if (TimeCompiler2) {
   575     tty->print(" ");
   576     target->holder()->name()->print();
   577     tty->print(".");
   578     target->print_short_name();
   579     tty->print("  ");
   580   }
   581   TraceTime t1("Total compilation time", &_t_totalCompilation, TimeCompiler, TimeCompiler2);
   582   TraceTime t2(NULL, &_t_methodCompilation, TimeCompiler, false);
   583   bool print_opto_assembly = PrintOptoAssembly || _method->has_option("PrintOptoAssembly");
   584   if (!print_opto_assembly) {
   585     bool print_assembly = (PrintAssembly || _method->should_print_assembly());
   586     if (print_assembly && !Disassembler::can_decode()) {
   587       tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
   588       print_opto_assembly = true;
   589     }
   590   }
   591   set_print_assembly(print_opto_assembly);
   592   set_parsed_irreducible_loop(false);
   593 #endif
   595   if (ProfileTraps) {
   596     // Make sure the method being compiled gets its own MDO,
   597     // so we can at least track the decompile_count().
   598     method()->ensure_method_data();
   599   }
   601   Init(::AliasLevel);
   604   print_compile_messages();
   606   if (UseOldInlining || PrintCompilation NOT_PRODUCT( || PrintOpto) )
   607     _ilt = InlineTree::build_inline_tree_root();
   608   else
   609     _ilt = NULL;
   611   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
   612   assert(num_alias_types() >= AliasIdxRaw, "");
   614 #define MINIMUM_NODE_HASH  1023
   615   // Node list that Iterative GVN will start with
   616   Unique_Node_List for_igvn(comp_arena());
   617   set_for_igvn(&for_igvn);
   619   // GVN that will be run immediately on new nodes
   620   uint estimated_size = method()->code_size()*4+64;
   621   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
   622   PhaseGVN gvn(node_arena(), estimated_size);
   623   set_initial_gvn(&gvn);
   625   { // Scope for timing the parser
   626     TracePhase t3("parse", &_t_parser, true);
   628     // Put top into the hash table ASAP.
   629     initial_gvn()->transform_no_reclaim(top());
   631     // Set up tf(), start(), and find a CallGenerator.
   632     CallGenerator* cg = NULL;
   633     if (is_osr_compilation()) {
   634       const TypeTuple *domain = StartOSRNode::osr_domain();
   635       const TypeTuple *range = TypeTuple::make_range(method()->signature());
   636       init_tf(TypeFunc::make(domain, range));
   637       StartNode* s = new (this, 2) StartOSRNode(root(), domain);
   638       initial_gvn()->set_type_bottom(s);
   639       init_start(s);
   640       cg = CallGenerator::for_osr(method(), entry_bci());
   641     } else {
   642       // Normal case.
   643       init_tf(TypeFunc::make(method()));
   644       StartNode* s = new (this, 2) StartNode(root(), tf()->domain());
   645       initial_gvn()->set_type_bottom(s);
   646       init_start(s);
   647       if (method()->intrinsic_id() == vmIntrinsics::_Reference_get && UseG1GC) {
   648         // With java.lang.ref.reference.get() we must go through the
   649         // intrinsic when G1 is enabled - even when get() is the root
   650         // method of the compile - so that, if necessary, the value in
   651         // the referent field of the reference object gets recorded by
   652         // the pre-barrier code.
   653         // Specifically, if G1 is enabled, the value in the referent
   654         // field is recorded by the G1 SATB pre barrier. This will
   655         // result in the referent being marked live and the reference
   656         // object removed from the list of discovered references during
   657         // reference processing.
   658         cg = find_intrinsic(method(), false);
   659       }
   660       if (cg == NULL) {
   661         float past_uses = method()->interpreter_invocation_count();
   662         float expected_uses = past_uses;
   663         cg = CallGenerator::for_inline(method(), expected_uses);
   664       }
   665     }
   666     if (failing())  return;
   667     if (cg == NULL) {
   668       record_method_not_compilable_all_tiers("cannot parse method");
   669       return;
   670     }
   671     JVMState* jvms = build_start_state(start(), tf());
   672     if ((jvms = cg->generate(jvms)) == NULL) {
   673       record_method_not_compilable("method parse failed");
   674       return;
   675     }
   676     GraphKit kit(jvms);
   678     if (!kit.stopped()) {
   679       // Accept return values, and transfer control we know not where.
   680       // This is done by a special, unique ReturnNode bound to root.
   681       return_values(kit.jvms());
   682     }
   684     if (kit.has_exceptions()) {
   685       // Any exceptions that escape from this call must be rethrown
   686       // to whatever caller is dynamically above us on the stack.
   687       // This is done by a special, unique RethrowNode bound to root.
   688       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
   689     }
   691     if (!failing() && has_stringbuilder()) {
   692       {
   693         // remove useless nodes to make the usage analysis simpler
   694         ResourceMark rm;
   695         PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
   696       }
   698       {
   699         ResourceMark rm;
   700         print_method("Before StringOpts", 3);
   701         PhaseStringOpts pso(initial_gvn(), &for_igvn);
   702         print_method("After StringOpts", 3);
   703       }
   705       // now inline anything that we skipped the first time around
   706       while (_late_inlines.length() > 0) {
   707         CallGenerator* cg = _late_inlines.pop();
   708         cg->do_late_inline();
   709       }
   710     }
   711     assert(_late_inlines.length() == 0, "should have been processed");
   713     print_method("Before RemoveUseless", 3);
   715     // Remove clutter produced by parsing.
   716     if (!failing()) {
   717       ResourceMark rm;
   718       PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
   719     }
   720   }
   722   // Note:  Large methods are capped off in do_one_bytecode().
   723   if (failing())  return;
   725   // After parsing, node notes are no longer automagic.
   726   // They must be propagated by register_new_node_with_optimizer(),
   727   // clone(), or the like.
   728   set_default_node_notes(NULL);
   730   for (;;) {
   731     int successes = Inline_Warm();
   732     if (failing())  return;
   733     if (successes == 0)  break;
   734   }
   736   // Drain the list.
   737   Finish_Warm();
   738 #ifndef PRODUCT
   739   if (_printer) {
   740     _printer->print_inlining(this);
   741   }
   742 #endif
   744   if (failing())  return;
   745   NOT_PRODUCT( verify_graph_edges(); )
   747   // Now optimize
   748   Optimize();
   749   if (failing())  return;
   750   NOT_PRODUCT( verify_graph_edges(); )
   752 #ifndef PRODUCT
   753   if (PrintIdeal) {
   754     ttyLocker ttyl;  // keep the following output all in one block
   755     // This output goes directly to the tty, not the compiler log.
   756     // To enable tools to match it up with the compilation activity,
   757     // be sure to tag this tty output with the compile ID.
   758     if (xtty != NULL) {
   759       xtty->head("ideal compile_id='%d'%s", compile_id(),
   760                  is_osr_compilation()    ? " compile_kind='osr'" :
   761                  "");
   762     }
   763     root()->dump(9999);
   764     if (xtty != NULL) {
   765       xtty->tail("ideal");
   766     }
   767   }
   768 #endif
   770   // Now that we know the size of all the monitors we can add a fixed slot
   771   // for the original deopt pc.
   773   _orig_pc_slot =  fixed_slots();
   774   int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
   775   set_fixed_slots(next_slot);
   777   // Now generate code
   778   Code_Gen();
   779   if (failing())  return;
   781   // Check if we want to skip execution of all compiled code.
   782   {
   783 #ifndef PRODUCT
   784     if (OptoNoExecute) {
   785       record_method_not_compilable("+OptoNoExecute");  // Flag as failed
   786       return;
   787     }
   788     TracePhase t2("install_code", &_t_registerMethod, TimeCompiler);
   789 #endif
   791     if (is_osr_compilation()) {
   792       _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
   793       _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
   794     } else {
   795       _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
   796       _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
   797     }
   799     env()->register_method(_method, _entry_bci,
   800                            &_code_offsets,
   801                            _orig_pc_slot_offset_in_bytes,
   802                            code_buffer(),
   803                            frame_size_in_words(), _oop_map_set,
   804                            &_handler_table, &_inc_table,
   805                            compiler,
   806                            env()->comp_level(),
   807                            true, /*has_debug_info*/
   808                            has_unsafe_access()
   809                            );
   810   }
   811 }
   813 //------------------------------Compile----------------------------------------
   814 // Compile a runtime stub
   815 Compile::Compile( ciEnv* ci_env,
   816                   TypeFunc_generator generator,
   817                   address stub_function,
   818                   const char *stub_name,
   819                   int is_fancy_jump,
   820                   bool pass_tls,
   821                   bool save_arg_registers,
   822                   bool return_pc )
   823   : Phase(Compiler),
   824     _env(ci_env),
   825     _log(ci_env->log()),
   826     _compile_id(-1),
   827     _save_argument_registers(save_arg_registers),
   828     _method(NULL),
   829     _stub_name(stub_name),
   830     _stub_function(stub_function),
   831     _stub_entry_point(NULL),
   832     _entry_bci(InvocationEntryBci),
   833     _initial_gvn(NULL),
   834     _for_igvn(NULL),
   835     _warm_calls(NULL),
   836     _orig_pc_slot(0),
   837     _orig_pc_slot_offset_in_bytes(0),
   838     _subsume_loads(true),
   839     _do_escape_analysis(false),
   840     _failure_reason(NULL),
   841     _code_buffer("Compile::Fill_buffer"),
   842     _has_method_handle_invokes(false),
   843     _mach_constant_base_node(NULL),
   844     _node_bundling_limit(0),
   845     _node_bundling_base(NULL),
   846     _java_calls(0),
   847     _inner_loops(0),
   848 #ifndef PRODUCT
   849     _trace_opto_output(TraceOptoOutput),
   850     _printer(NULL),
   851 #endif
   852     _congraph(NULL) {
   853   C = this;
   855 #ifndef PRODUCT
   856   TraceTime t1(NULL, &_t_totalCompilation, TimeCompiler, false);
   857   TraceTime t2(NULL, &_t_stubCompilation, TimeCompiler, false);
   858   set_print_assembly(PrintFrameConverterAssembly);
   859   set_parsed_irreducible_loop(false);
   860 #endif
   861   CompileWrapper cw(this);
   862   Init(/*AliasLevel=*/ 0);
   863   init_tf((*generator)());
   865   {
   866     // The following is a dummy for the sake of GraphKit::gen_stub
   867     Unique_Node_List for_igvn(comp_arena());
   868     set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
   869     PhaseGVN gvn(Thread::current()->resource_area(),255);
   870     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
   871     gvn.transform_no_reclaim(top());
   873     GraphKit kit;
   874     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
   875   }
   877   NOT_PRODUCT( verify_graph_edges(); )
   878   Code_Gen();
   879   if (failing())  return;
   882   // Entry point will be accessed using compile->stub_entry_point();
   883   if (code_buffer() == NULL) {
   884     Matcher::soft_match_failure();
   885   } else {
   886     if (PrintAssembly && (WizardMode || Verbose))
   887       tty->print_cr("### Stub::%s", stub_name);
   889     if (!failing()) {
   890       assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
   892       // Make the NMethod
   893       // For now we mark the frame as never safe for profile stackwalking
   894       RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
   895                                                       code_buffer(),
   896                                                       CodeOffsets::frame_never_safe,
   897                                                       // _code_offsets.value(CodeOffsets::Frame_Complete),
   898                                                       frame_size_in_words(),
   899                                                       _oop_map_set,
   900                                                       save_arg_registers);
   901       assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
   903       _stub_entry_point = rs->entry_point();
   904     }
   905   }
   906 }
   908 #ifndef PRODUCT
   909 void print_opto_verbose_signature( const TypeFunc *j_sig, const char *stub_name ) {
   910   if(PrintOpto && Verbose) {
   911     tty->print("%s   ", stub_name); j_sig->print_flattened(); tty->cr();
   912   }
   913 }
   914 #endif
   916 void Compile::print_codes() {
   917 }
   919 //------------------------------Init-------------------------------------------
   920 // Prepare for a single compilation
   921 void Compile::Init(int aliaslevel) {
   922   _unique  = 0;
   923   _regalloc = NULL;
   925   _tf      = NULL;  // filled in later
   926   _top     = NULL;  // cached later
   927   _matcher = NULL;  // filled in later
   928   _cfg     = NULL;  // filled in later
   930   set_24_bit_selection_and_mode(Use24BitFP, false);
   932   _node_note_array = NULL;
   933   _default_node_notes = NULL;
   935   _immutable_memory = NULL; // filled in at first inquiry
   937   // Globally visible Nodes
   938   // First set TOP to NULL to give safe behavior during creation of RootNode
   939   set_cached_top_node(NULL);
   940   set_root(new (this, 3) RootNode());
   941   // Now that you have a Root to point to, create the real TOP
   942   set_cached_top_node( new (this, 1) ConNode(Type::TOP) );
   943   set_recent_alloc(NULL, NULL);
   945   // Create Debug Information Recorder to record scopes, oopmaps, etc.
   946   env()->set_oop_recorder(new OopRecorder(comp_arena()));
   947   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
   948   env()->set_dependencies(new Dependencies(env()));
   950   _fixed_slots = 0;
   951   set_has_split_ifs(false);
   952   set_has_loops(has_method() && method()->has_loops()); // first approximation
   953   set_has_stringbuilder(false);
   954   _trap_can_recompile = false;  // no traps emitted yet
   955   _major_progress = true; // start out assuming good things will happen
   956   set_has_unsafe_access(false);
   957   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
   958   set_decompile_count(0);
   960   set_do_freq_based_layout(BlockLayoutByFrequency || method_has_option("BlockLayoutByFrequency"));
   961   set_num_loop_opts(LoopOptsCount);
   962   set_do_inlining(Inline);
   963   set_max_inline_size(MaxInlineSize);
   964   set_freq_inline_size(FreqInlineSize);
   965   set_do_scheduling(OptoScheduling);
   966   set_do_count_invocations(false);
   967   set_do_method_data_update(false);
   969   if (debug_info()->recording_non_safepoints()) {
   970     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
   971                         (comp_arena(), 8, 0, NULL));
   972     set_default_node_notes(Node_Notes::make(this));
   973   }
   975   // // -- Initialize types before each compile --
   976   // // Update cached type information
   977   // if( _method && _method->constants() )
   978   //   Type::update_loaded_types(_method, _method->constants());
   980   // Init alias_type map.
   981   if (!_do_escape_analysis && aliaslevel == 3)
   982     aliaslevel = 2;  // No unique types without escape analysis
   983   _AliasLevel = aliaslevel;
   984   const int grow_ats = 16;
   985   _max_alias_types = grow_ats;
   986   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
   987   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
   988   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
   989   {
   990     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
   991   }
   992   // Initialize the first few types.
   993   _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
   994   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
   995   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
   996   _num_alias_types = AliasIdxRaw+1;
   997   // Zero out the alias type cache.
   998   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
   999   // A NULL adr_type hits in the cache right away.  Preload the right answer.
  1000   probe_alias_cache(NULL)->_index = AliasIdxTop;
  1002   _intrinsics = NULL;
  1003   _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1004   _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1005   register_library_intrinsics();
  1008 //---------------------------init_start----------------------------------------
  1009 // Install the StartNode on this compile object.
  1010 void Compile::init_start(StartNode* s) {
  1011   if (failing())
  1012     return; // already failing
  1013   assert(s == start(), "");
  1016 StartNode* Compile::start() const {
  1017   assert(!failing(), "");
  1018   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
  1019     Node* start = root()->fast_out(i);
  1020     if( start->is_Start() )
  1021       return start->as_Start();
  1023   ShouldNotReachHere();
  1024   return NULL;
  1027 //-------------------------------immutable_memory-------------------------------------
  1028 // Access immutable memory
  1029 Node* Compile::immutable_memory() {
  1030   if (_immutable_memory != NULL) {
  1031     return _immutable_memory;
  1033   StartNode* s = start();
  1034   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
  1035     Node *p = s->fast_out(i);
  1036     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
  1037       _immutable_memory = p;
  1038       return _immutable_memory;
  1041   ShouldNotReachHere();
  1042   return NULL;
  1045 //----------------------set_cached_top_node------------------------------------
  1046 // Install the cached top node, and make sure Node::is_top works correctly.
  1047 void Compile::set_cached_top_node(Node* tn) {
  1048   if (tn != NULL)  verify_top(tn);
  1049   Node* old_top = _top;
  1050   _top = tn;
  1051   // Calling Node::setup_is_top allows the nodes the chance to adjust
  1052   // their _out arrays.
  1053   if (_top != NULL)     _top->setup_is_top();
  1054   if (old_top != NULL)  old_top->setup_is_top();
  1055   assert(_top == NULL || top()->is_top(), "");
  1058 #ifndef PRODUCT
  1059 void Compile::verify_top(Node* tn) const {
  1060   if (tn != NULL) {
  1061     assert(tn->is_Con(), "top node must be a constant");
  1062     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
  1063     assert(tn->in(0) != NULL, "must have live top node");
  1066 #endif
  1069 ///-------------------Managing Per-Node Debug & Profile Info-------------------
  1071 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
  1072   guarantee(arr != NULL, "");
  1073   int num_blocks = arr->length();
  1074   if (grow_by < num_blocks)  grow_by = num_blocks;
  1075   int num_notes = grow_by * _node_notes_block_size;
  1076   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
  1077   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
  1078   while (num_notes > 0) {
  1079     arr->append(notes);
  1080     notes     += _node_notes_block_size;
  1081     num_notes -= _node_notes_block_size;
  1083   assert(num_notes == 0, "exact multiple, please");
  1086 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
  1087   if (source == NULL || dest == NULL)  return false;
  1089   if (dest->is_Con())
  1090     return false;               // Do not push debug info onto constants.
  1092 #ifdef ASSERT
  1093   // Leave a bread crumb trail pointing to the original node:
  1094   if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
  1095     dest->set_debug_orig(source);
  1097 #endif
  1099   if (node_note_array() == NULL)
  1100     return false;               // Not collecting any notes now.
  1102   // This is a copy onto a pre-existing node, which may already have notes.
  1103   // If both nodes have notes, do not overwrite any pre-existing notes.
  1104   Node_Notes* source_notes = node_notes_at(source->_idx);
  1105   if (source_notes == NULL || source_notes->is_clear())  return false;
  1106   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
  1107   if (dest_notes == NULL || dest_notes->is_clear()) {
  1108     return set_node_notes_at(dest->_idx, source_notes);
  1111   Node_Notes merged_notes = (*source_notes);
  1112   // The order of operations here ensures that dest notes will win...
  1113   merged_notes.update_from(dest_notes);
  1114   return set_node_notes_at(dest->_idx, &merged_notes);
  1118 //--------------------------allow_range_check_smearing-------------------------
  1119 // Gating condition for coalescing similar range checks.
  1120 // Sometimes we try 'speculatively' replacing a series of a range checks by a
  1121 // single covering check that is at least as strong as any of them.
  1122 // If the optimization succeeds, the simplified (strengthened) range check
  1123 // will always succeed.  If it fails, we will deopt, and then give up
  1124 // on the optimization.
  1125 bool Compile::allow_range_check_smearing() const {
  1126   // If this method has already thrown a range-check,
  1127   // assume it was because we already tried range smearing
  1128   // and it failed.
  1129   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
  1130   return !already_trapped;
  1134 //------------------------------flatten_alias_type-----------------------------
  1135 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
  1136   int offset = tj->offset();
  1137   TypePtr::PTR ptr = tj->ptr();
  1139   // Known instance (scalarizable allocation) alias only with itself.
  1140   bool is_known_inst = tj->isa_oopptr() != NULL &&
  1141                        tj->is_oopptr()->is_known_instance();
  1143   // Process weird unsafe references.
  1144   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
  1145     assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
  1146     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
  1147     tj = TypeOopPtr::BOTTOM;
  1148     ptr = tj->ptr();
  1149     offset = tj->offset();
  1152   // Array pointers need some flattening
  1153   const TypeAryPtr *ta = tj->isa_aryptr();
  1154   if( ta && is_known_inst ) {
  1155     if ( offset != Type::OffsetBot &&
  1156          offset > arrayOopDesc::length_offset_in_bytes() ) {
  1157       offset = Type::OffsetBot; // Flatten constant access into array body only
  1158       tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
  1160   } else if( ta && _AliasLevel >= 2 ) {
  1161     // For arrays indexed by constant indices, we flatten the alias
  1162     // space to include all of the array body.  Only the header, klass
  1163     // and array length can be accessed un-aliased.
  1164     if( offset != Type::OffsetBot ) {
  1165       if( ta->const_oop() ) { // methodDataOop or methodOop
  1166         offset = Type::OffsetBot;   // Flatten constant access into array body
  1167         tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
  1168       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
  1169         // range is OK as-is.
  1170         tj = ta = TypeAryPtr::RANGE;
  1171       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
  1172         tj = TypeInstPtr::KLASS; // all klass loads look alike
  1173         ta = TypeAryPtr::RANGE; // generic ignored junk
  1174         ptr = TypePtr::BotPTR;
  1175       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
  1176         tj = TypeInstPtr::MARK;
  1177         ta = TypeAryPtr::RANGE; // generic ignored junk
  1178         ptr = TypePtr::BotPTR;
  1179       } else {                  // Random constant offset into array body
  1180         offset = Type::OffsetBot;   // Flatten constant access into array body
  1181         tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
  1184     // Arrays of fixed size alias with arrays of unknown size.
  1185     if (ta->size() != TypeInt::POS) {
  1186       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
  1187       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
  1189     // Arrays of known objects become arrays of unknown objects.
  1190     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
  1191       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
  1192       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
  1194     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
  1195       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
  1196       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
  1198     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
  1199     // cannot be distinguished by bytecode alone.
  1200     if (ta->elem() == TypeInt::BOOL) {
  1201       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
  1202       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
  1203       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
  1205     // During the 2nd round of IterGVN, NotNull castings are removed.
  1206     // Make sure the Bottom and NotNull variants alias the same.
  1207     // Also, make sure exact and non-exact variants alias the same.
  1208     if( ptr == TypePtr::NotNull || ta->klass_is_exact() ) {
  1209       if (ta->const_oop()) {
  1210         tj = ta = TypeAryPtr::make(TypePtr::Constant,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
  1211       } else {
  1212         tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
  1217   // Oop pointers need some flattening
  1218   const TypeInstPtr *to = tj->isa_instptr();
  1219   if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
  1220     ciInstanceKlass *k = to->klass()->as_instance_klass();
  1221     if( ptr == TypePtr::Constant ) {
  1222       if (to->klass() != ciEnv::current()->Class_klass() ||
  1223           offset < k->size_helper() * wordSize) {
  1224         // No constant oop pointers (such as Strings); they alias with
  1225         // unknown strings.
  1226         assert(!is_known_inst, "not scalarizable allocation");
  1227         tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
  1229     } else if( is_known_inst ) {
  1230       tj = to; // Keep NotNull and klass_is_exact for instance type
  1231     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
  1232       // During the 2nd round of IterGVN, NotNull castings are removed.
  1233       // Make sure the Bottom and NotNull variants alias the same.
  1234       // Also, make sure exact and non-exact variants alias the same.
  1235       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
  1237     // Canonicalize the holder of this field
  1238     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
  1239       // First handle header references such as a LoadKlassNode, even if the
  1240       // object's klass is unloaded at compile time (4965979).
  1241       if (!is_known_inst) { // Do it only for non-instance types
  1242         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
  1244     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
  1245       // Static fields are in the space above the normal instance
  1246       // fields in the java.lang.Class instance.
  1247       if (to->klass() != ciEnv::current()->Class_klass()) {
  1248         to = NULL;
  1249         tj = TypeOopPtr::BOTTOM;
  1250         offset = tj->offset();
  1252     } else {
  1253       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
  1254       if (!k->equals(canonical_holder) || tj->offset() != offset) {
  1255         if( is_known_inst ) {
  1256           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
  1257         } else {
  1258           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
  1264   // Klass pointers to object array klasses need some flattening
  1265   const TypeKlassPtr *tk = tj->isa_klassptr();
  1266   if( tk ) {
  1267     // If we are referencing a field within a Klass, we need
  1268     // to assume the worst case of an Object.  Both exact and
  1269     // inexact types must flatten to the same alias class.
  1270     // Since the flattened result for a klass is defined to be
  1271     // precisely java.lang.Object, use a constant ptr.
  1272     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
  1274       tj = tk = TypeKlassPtr::make(TypePtr::Constant,
  1275                                    TypeKlassPtr::OBJECT->klass(),
  1276                                    offset);
  1279     ciKlass* klass = tk->klass();
  1280     if( klass->is_obj_array_klass() ) {
  1281       ciKlass* k = TypeAryPtr::OOPS->klass();
  1282       if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
  1283         k = TypeInstPtr::BOTTOM->klass();
  1284       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
  1287     // Check for precise loads from the primary supertype array and force them
  1288     // to the supertype cache alias index.  Check for generic array loads from
  1289     // the primary supertype array and also force them to the supertype cache
  1290     // alias index.  Since the same load can reach both, we need to merge
  1291     // these 2 disparate memories into the same alias class.  Since the
  1292     // primary supertype array is read-only, there's no chance of confusion
  1293     // where we bypass an array load and an array store.
  1294     uint off2 = offset - Klass::primary_supers_offset_in_bytes();
  1295     if( offset == Type::OffsetBot ||
  1296         off2 < Klass::primary_super_limit()*wordSize ) {
  1297       offset = sizeof(oopDesc) +Klass::secondary_super_cache_offset_in_bytes();
  1298       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
  1302   // Flatten all Raw pointers together.
  1303   if (tj->base() == Type::RawPtr)
  1304     tj = TypeRawPtr::BOTTOM;
  1306   if (tj->base() == Type::AnyPtr)
  1307     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
  1309   // Flatten all to bottom for now
  1310   switch( _AliasLevel ) {
  1311   case 0:
  1312     tj = TypePtr::BOTTOM;
  1313     break;
  1314   case 1:                       // Flatten to: oop, static, field or array
  1315     switch (tj->base()) {
  1316     //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
  1317     case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
  1318     case Type::AryPtr:   // do not distinguish arrays at all
  1319     case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
  1320     case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
  1321     case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
  1322     default: ShouldNotReachHere();
  1324     break;
  1325   case 2:                       // No collapsing at level 2; keep all splits
  1326   case 3:                       // No collapsing at level 3; keep all splits
  1327     break;
  1328   default:
  1329     Unimplemented();
  1332   offset = tj->offset();
  1333   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
  1335   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
  1336           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
  1337           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
  1338           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
  1339           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
  1340           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
  1341           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr)  ,
  1342           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
  1343   assert( tj->ptr() != TypePtr::TopPTR &&
  1344           tj->ptr() != TypePtr::AnyNull &&
  1345           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
  1346 //    assert( tj->ptr() != TypePtr::Constant ||
  1347 //            tj->base() == Type::RawPtr ||
  1348 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
  1350   return tj;
  1353 void Compile::AliasType::Init(int i, const TypePtr* at) {
  1354   _index = i;
  1355   _adr_type = at;
  1356   _field = NULL;
  1357   _is_rewritable = true; // default
  1358   const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
  1359   if (atoop != NULL && atoop->is_known_instance()) {
  1360     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
  1361     _general_index = Compile::current()->get_alias_index(gt);
  1362   } else {
  1363     _general_index = 0;
  1367 //---------------------------------print_on------------------------------------
  1368 #ifndef PRODUCT
  1369 void Compile::AliasType::print_on(outputStream* st) {
  1370   if (index() < 10)
  1371         st->print("@ <%d> ", index());
  1372   else  st->print("@ <%d>",  index());
  1373   st->print(is_rewritable() ? "   " : " RO");
  1374   int offset = adr_type()->offset();
  1375   if (offset == Type::OffsetBot)
  1376         st->print(" +any");
  1377   else  st->print(" +%-3d", offset);
  1378   st->print(" in ");
  1379   adr_type()->dump_on(st);
  1380   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
  1381   if (field() != NULL && tjp) {
  1382     if (tjp->klass()  != field()->holder() ||
  1383         tjp->offset() != field()->offset_in_bytes()) {
  1384       st->print(" != ");
  1385       field()->print();
  1386       st->print(" ***");
  1391 void print_alias_types() {
  1392   Compile* C = Compile::current();
  1393   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
  1394   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
  1395     C->alias_type(idx)->print_on(tty);
  1396     tty->cr();
  1399 #endif
  1402 //----------------------------probe_alias_cache--------------------------------
  1403 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
  1404   intptr_t key = (intptr_t) adr_type;
  1405   key ^= key >> logAliasCacheSize;
  1406   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
  1410 //-----------------------------grow_alias_types--------------------------------
  1411 void Compile::grow_alias_types() {
  1412   const int old_ats  = _max_alias_types; // how many before?
  1413   const int new_ats  = old_ats;          // how many more?
  1414   const int grow_ats = old_ats+new_ats;  // how many now?
  1415   _max_alias_types = grow_ats;
  1416   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
  1417   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
  1418   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
  1419   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
  1423 //--------------------------------find_alias_type------------------------------
  1424 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
  1425   if (_AliasLevel == 0)
  1426     return alias_type(AliasIdxBot);
  1428   AliasCacheEntry* ace = probe_alias_cache(adr_type);
  1429   if (ace->_adr_type == adr_type) {
  1430     return alias_type(ace->_index);
  1433   // Handle special cases.
  1434   if (adr_type == NULL)             return alias_type(AliasIdxTop);
  1435   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
  1437   // Do it the slow way.
  1438   const TypePtr* flat = flatten_alias_type(adr_type);
  1440 #ifdef ASSERT
  1441   assert(flat == flatten_alias_type(flat), "idempotent");
  1442   assert(flat != TypePtr::BOTTOM,     "cannot alias-analyze an untyped ptr");
  1443   if (flat->isa_oopptr() && !flat->isa_klassptr()) {
  1444     const TypeOopPtr* foop = flat->is_oopptr();
  1445     // Scalarizable allocations have exact klass always.
  1446     bool exact = !foop->klass_is_exact() || foop->is_known_instance();
  1447     const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
  1448     assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type");
  1450   assert(flat == flatten_alias_type(flat), "exact bit doesn't matter");
  1451 #endif
  1453   int idx = AliasIdxTop;
  1454   for (int i = 0; i < num_alias_types(); i++) {
  1455     if (alias_type(i)->adr_type() == flat) {
  1456       idx = i;
  1457       break;
  1461   if (idx == AliasIdxTop) {
  1462     if (no_create)  return NULL;
  1463     // Grow the array if necessary.
  1464     if (_num_alias_types == _max_alias_types)  grow_alias_types();
  1465     // Add a new alias type.
  1466     idx = _num_alias_types++;
  1467     _alias_types[idx]->Init(idx, flat);
  1468     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
  1469     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
  1470     if (flat->isa_instptr()) {
  1471       if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
  1472           && flat->is_instptr()->klass() == env()->Class_klass())
  1473         alias_type(idx)->set_rewritable(false);
  1475     if (flat->isa_klassptr()) {
  1476       if (flat->offset() == Klass::super_check_offset_offset_in_bytes() + (int)sizeof(oopDesc))
  1477         alias_type(idx)->set_rewritable(false);
  1478       if (flat->offset() == Klass::modifier_flags_offset_in_bytes() + (int)sizeof(oopDesc))
  1479         alias_type(idx)->set_rewritable(false);
  1480       if (flat->offset() == Klass::access_flags_offset_in_bytes() + (int)sizeof(oopDesc))
  1481         alias_type(idx)->set_rewritable(false);
  1482       if (flat->offset() == Klass::java_mirror_offset_in_bytes() + (int)sizeof(oopDesc))
  1483         alias_type(idx)->set_rewritable(false);
  1485     // %%% (We would like to finalize JavaThread::threadObj_offset(),
  1486     // but the base pointer type is not distinctive enough to identify
  1487     // references into JavaThread.)
  1489     // Check for final fields.
  1490     const TypeInstPtr* tinst = flat->isa_instptr();
  1491     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
  1492       ciField* field;
  1493       if (tinst->const_oop() != NULL &&
  1494           tinst->klass() == ciEnv::current()->Class_klass() &&
  1495           tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
  1496         // static field
  1497         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
  1498         field = k->get_field_by_offset(tinst->offset(), true);
  1499       } else {
  1500         ciInstanceKlass *k = tinst->klass()->as_instance_klass();
  1501         field = k->get_field_by_offset(tinst->offset(), false);
  1503       assert(field == NULL ||
  1504              original_field == NULL ||
  1505              (field->holder() == original_field->holder() &&
  1506               field->offset() == original_field->offset() &&
  1507               field->is_static() == original_field->is_static()), "wrong field?");
  1508       // Set field() and is_rewritable() attributes.
  1509       if (field != NULL)  alias_type(idx)->set_field(field);
  1513   // Fill the cache for next time.
  1514   ace->_adr_type = adr_type;
  1515   ace->_index    = idx;
  1516   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
  1518   // Might as well try to fill the cache for the flattened version, too.
  1519   AliasCacheEntry* face = probe_alias_cache(flat);
  1520   if (face->_adr_type == NULL) {
  1521     face->_adr_type = flat;
  1522     face->_index    = idx;
  1523     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
  1526   return alias_type(idx);
  1530 Compile::AliasType* Compile::alias_type(ciField* field) {
  1531   const TypeOopPtr* t;
  1532   if (field->is_static())
  1533     t = TypeInstPtr::make(field->holder()->java_mirror());
  1534   else
  1535     t = TypeOopPtr::make_from_klass_raw(field->holder());
  1536   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
  1537   assert(field->is_final() == !atp->is_rewritable(), "must get the rewritable bits correct");
  1538   return atp;
  1542 //------------------------------have_alias_type--------------------------------
  1543 bool Compile::have_alias_type(const TypePtr* adr_type) {
  1544   AliasCacheEntry* ace = probe_alias_cache(adr_type);
  1545   if (ace->_adr_type == adr_type) {
  1546     return true;
  1549   // Handle special cases.
  1550   if (adr_type == NULL)             return true;
  1551   if (adr_type == TypePtr::BOTTOM)  return true;
  1553   return find_alias_type(adr_type, true, NULL) != NULL;
  1556 //-----------------------------must_alias--------------------------------------
  1557 // True if all values of the given address type are in the given alias category.
  1558 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
  1559   if (alias_idx == AliasIdxBot)         return true;  // the universal category
  1560   if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
  1561   if (alias_idx == AliasIdxTop)         return false; // the empty category
  1562   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
  1564   // the only remaining possible overlap is identity
  1565   int adr_idx = get_alias_index(adr_type);
  1566   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
  1567   assert(adr_idx == alias_idx ||
  1568          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
  1569           && adr_type                       != TypeOopPtr::BOTTOM),
  1570          "should not be testing for overlap with an unsafe pointer");
  1571   return adr_idx == alias_idx;
  1574 //------------------------------can_alias--------------------------------------
  1575 // True if any values of the given address type are in the given alias category.
  1576 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
  1577   if (alias_idx == AliasIdxTop)         return false; // the empty category
  1578   if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
  1579   if (alias_idx == AliasIdxBot)         return true;  // the universal category
  1580   if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
  1582   // the only remaining possible overlap is identity
  1583   int adr_idx = get_alias_index(adr_type);
  1584   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
  1585   return adr_idx == alias_idx;
  1590 //---------------------------pop_warm_call-------------------------------------
  1591 WarmCallInfo* Compile::pop_warm_call() {
  1592   WarmCallInfo* wci = _warm_calls;
  1593   if (wci != NULL)  _warm_calls = wci->remove_from(wci);
  1594   return wci;
  1597 //----------------------------Inline_Warm--------------------------------------
  1598 int Compile::Inline_Warm() {
  1599   // If there is room, try to inline some more warm call sites.
  1600   // %%% Do a graph index compaction pass when we think we're out of space?
  1601   if (!InlineWarmCalls)  return 0;
  1603   int calls_made_hot = 0;
  1604   int room_to_grow   = NodeCountInliningCutoff - unique();
  1605   int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
  1606   int amount_grown   = 0;
  1607   WarmCallInfo* call;
  1608   while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
  1609     int est_size = (int)call->size();
  1610     if (est_size > (room_to_grow - amount_grown)) {
  1611       // This one won't fit anyway.  Get rid of it.
  1612       call->make_cold();
  1613       continue;
  1615     call->make_hot();
  1616     calls_made_hot++;
  1617     amount_grown   += est_size;
  1618     amount_to_grow -= est_size;
  1621   if (calls_made_hot > 0)  set_major_progress();
  1622   return calls_made_hot;
  1626 //----------------------------Finish_Warm--------------------------------------
  1627 void Compile::Finish_Warm() {
  1628   if (!InlineWarmCalls)  return;
  1629   if (failing())  return;
  1630   if (warm_calls() == NULL)  return;
  1632   // Clean up loose ends, if we are out of space for inlining.
  1633   WarmCallInfo* call;
  1634   while ((call = pop_warm_call()) != NULL) {
  1635     call->make_cold();
  1639 //---------------------cleanup_loop_predicates-----------------------
  1640 // Remove the opaque nodes that protect the predicates so that all unused
  1641 // checks and uncommon_traps will be eliminated from the ideal graph
  1642 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
  1643   if (predicate_count()==0) return;
  1644   for (int i = predicate_count(); i > 0; i--) {
  1645     Node * n = predicate_opaque1_node(i-1);
  1646     assert(n->Opcode() == Op_Opaque1, "must be");
  1647     igvn.replace_node(n, n->in(1));
  1649   assert(predicate_count()==0, "should be clean!");
  1650   igvn.optimize();
  1653 //------------------------------Optimize---------------------------------------
  1654 // Given a graph, optimize it.
  1655 void Compile::Optimize() {
  1656   TracePhase t1("optimizer", &_t_optimizer, true);
  1658 #ifndef PRODUCT
  1659   if (env()->break_at_compile()) {
  1660     BREAKPOINT;
  1663 #endif
  1665   ResourceMark rm;
  1666   int          loop_opts_cnt;
  1668   NOT_PRODUCT( verify_graph_edges(); )
  1670   print_method("After Parsing");
  1673   // Iterative Global Value Numbering, including ideal transforms
  1674   // Initialize IterGVN with types and values from parse-time GVN
  1675   PhaseIterGVN igvn(initial_gvn());
  1677     NOT_PRODUCT( TracePhase t2("iterGVN", &_t_iterGVN, TimeCompiler); )
  1678     igvn.optimize();
  1681   print_method("Iter GVN 1", 2);
  1683   if (failing())  return;
  1685   // Perform escape analysis
  1686   if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
  1687     TracePhase t2("escapeAnalysis", &_t_escapeAnalysis, true);
  1688     ConnectionGraph::do_analysis(this, &igvn);
  1690     if (failing())  return;
  1692     igvn.optimize();
  1693     print_method("Iter GVN 3", 2);
  1695     if (failing())  return;
  1699   // Loop transforms on the ideal graph.  Range Check Elimination,
  1700   // peeling, unrolling, etc.
  1702   // Set loop opts counter
  1703   loop_opts_cnt = num_loop_opts();
  1704   if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
  1706       TracePhase t2("idealLoop", &_t_idealLoop, true);
  1707       PhaseIdealLoop ideal_loop( igvn, true, UseLoopPredicate);
  1708       loop_opts_cnt--;
  1709       if (major_progress()) print_method("PhaseIdealLoop 1", 2);
  1710       if (failing())  return;
  1712     // Loop opts pass if partial peeling occurred in previous pass
  1713     if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
  1714       TracePhase t3("idealLoop", &_t_idealLoop, true);
  1715       PhaseIdealLoop ideal_loop( igvn, false, UseLoopPredicate);
  1716       loop_opts_cnt--;
  1717       if (major_progress()) print_method("PhaseIdealLoop 2", 2);
  1718       if (failing())  return;
  1720     // Loop opts pass for loop-unrolling before CCP
  1721     if(major_progress() && (loop_opts_cnt > 0)) {
  1722       TracePhase t4("idealLoop", &_t_idealLoop, true);
  1723       PhaseIdealLoop ideal_loop( igvn, false, UseLoopPredicate);
  1724       loop_opts_cnt--;
  1725       if (major_progress()) print_method("PhaseIdealLoop 3", 2);
  1727     if (!failing()) {
  1728       // Verify that last round of loop opts produced a valid graph
  1729       NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
  1730       PhaseIdealLoop::verify(igvn);
  1733   if (failing())  return;
  1735   // Conditional Constant Propagation;
  1736   PhaseCCP ccp( &igvn );
  1737   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
  1739     TracePhase t2("ccp", &_t_ccp, true);
  1740     ccp.do_transform();
  1742   print_method("PhaseCPP 1", 2);
  1744   assert( true, "Break here to ccp.dump_old2new_map()");
  1746   // Iterative Global Value Numbering, including ideal transforms
  1748     NOT_PRODUCT( TracePhase t2("iterGVN2", &_t_iterGVN2, TimeCompiler); )
  1749     igvn = ccp;
  1750     igvn.optimize();
  1753   print_method("Iter GVN 2", 2);
  1755   if (failing())  return;
  1757   // Loop transforms on the ideal graph.  Range Check Elimination,
  1758   // peeling, unrolling, etc.
  1759   if(loop_opts_cnt > 0) {
  1760     debug_only( int cnt = 0; );
  1761     bool loop_predication = UseLoopPredicate;
  1762     while(major_progress() && (loop_opts_cnt > 0)) {
  1763       TracePhase t2("idealLoop", &_t_idealLoop, true);
  1764       assert( cnt++ < 40, "infinite cycle in loop optimization" );
  1765       PhaseIdealLoop ideal_loop( igvn, true, loop_predication);
  1766       loop_opts_cnt--;
  1767       if (major_progress()) print_method("PhaseIdealLoop iterations", 2);
  1768       if (failing())  return;
  1769       // Perform loop predication optimization during first iteration after CCP.
  1770       // After that switch it off and cleanup unused loop predicates.
  1771       if (loop_predication) {
  1772         loop_predication = false;
  1773         cleanup_loop_predicates(igvn);
  1774         if (failing())  return;
  1780     // Verify that all previous optimizations produced a valid graph
  1781     // at least to this point, even if no loop optimizations were done.
  1782     NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
  1783     PhaseIdealLoop::verify(igvn);
  1787     NOT_PRODUCT( TracePhase t2("macroExpand", &_t_macroExpand, TimeCompiler); )
  1788     PhaseMacroExpand  mex(igvn);
  1789     if (mex.expand_macro_nodes()) {
  1790       assert(failing(), "must bail out w/ explicit message");
  1791       return;
  1795  } // (End scope of igvn; run destructor if necessary for asserts.)
  1797   // A method with only infinite loops has no edges entering loops from root
  1799     NOT_PRODUCT( TracePhase t2("graphReshape", &_t_graphReshaping, TimeCompiler); )
  1800     if (final_graph_reshaping()) {
  1801       assert(failing(), "must bail out w/ explicit message");
  1802       return;
  1806   print_method("Optimize finished", 2);
  1810 //------------------------------Code_Gen---------------------------------------
  1811 // Given a graph, generate code for it
  1812 void Compile::Code_Gen() {
  1813   if (failing())  return;
  1815   // Perform instruction selection.  You might think we could reclaim Matcher
  1816   // memory PDQ, but actually the Matcher is used in generating spill code.
  1817   // Internals of the Matcher (including some VectorSets) must remain live
  1818   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
  1819   // set a bit in reclaimed memory.
  1821   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
  1822   // nodes.  Mapping is only valid at the root of each matched subtree.
  1823   NOT_PRODUCT( verify_graph_edges(); )
  1825   Node_List proj_list;
  1826   Matcher m(proj_list);
  1827   _matcher = &m;
  1829     TracePhase t2("matcher", &_t_matcher, true);
  1830     m.match();
  1832   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
  1833   // nodes.  Mapping is only valid at the root of each matched subtree.
  1834   NOT_PRODUCT( verify_graph_edges(); )
  1836   // If you have too many nodes, or if matching has failed, bail out
  1837   check_node_count(0, "out of nodes matching instructions");
  1838   if (failing())  return;
  1840   // Build a proper-looking CFG
  1841   PhaseCFG cfg(node_arena(), root(), m);
  1842   _cfg = &cfg;
  1844     NOT_PRODUCT( TracePhase t2("scheduler", &_t_scheduler, TimeCompiler); )
  1845     cfg.Dominators();
  1846     if (failing())  return;
  1848     NOT_PRODUCT( verify_graph_edges(); )
  1850     cfg.Estimate_Block_Frequency();
  1851     cfg.GlobalCodeMotion(m,unique(),proj_list);
  1853     print_method("Global code motion", 2);
  1855     if (failing())  return;
  1856     NOT_PRODUCT( verify_graph_edges(); )
  1858     debug_only( cfg.verify(); )
  1860   NOT_PRODUCT( verify_graph_edges(); )
  1862   PhaseChaitin regalloc(unique(),cfg,m);
  1863   _regalloc = &regalloc;
  1865     TracePhase t2("regalloc", &_t_registerAllocation, true);
  1866     // Perform any platform dependent preallocation actions.  This is used,
  1867     // for example, to avoid taking an implicit null pointer exception
  1868     // using the frame pointer on win95.
  1869     _regalloc->pd_preallocate_hook();
  1871     // Perform register allocation.  After Chaitin, use-def chains are
  1872     // no longer accurate (at spill code) and so must be ignored.
  1873     // Node->LRG->reg mappings are still accurate.
  1874     _regalloc->Register_Allocate();
  1876     // Bail out if the allocator builds too many nodes
  1877     if (failing())  return;
  1880   // Prior to register allocation we kept empty basic blocks in case the
  1881   // the allocator needed a place to spill.  After register allocation we
  1882   // are not adding any new instructions.  If any basic block is empty, we
  1883   // can now safely remove it.
  1885     NOT_PRODUCT( TracePhase t2("blockOrdering", &_t_blockOrdering, TimeCompiler); )
  1886     cfg.remove_empty();
  1887     if (do_freq_based_layout()) {
  1888       PhaseBlockLayout layout(cfg);
  1889     } else {
  1890       cfg.set_loop_alignment();
  1892     cfg.fixup_flow();
  1895   // Perform any platform dependent postallocation verifications.
  1896   debug_only( _regalloc->pd_postallocate_verify_hook(); )
  1898   // Apply peephole optimizations
  1899   if( OptoPeephole ) {
  1900     NOT_PRODUCT( TracePhase t2("peephole", &_t_peephole, TimeCompiler); )
  1901     PhasePeephole peep( _regalloc, cfg);
  1902     peep.do_transform();
  1905   // Convert Nodes to instruction bits in a buffer
  1907     // %%%% workspace merge brought two timers together for one job
  1908     TracePhase t2a("output", &_t_output, true);
  1909     NOT_PRODUCT( TraceTime t2b(NULL, &_t_codeGeneration, TimeCompiler, false); )
  1910     Output();
  1913   print_method("Final Code");
  1915   // He's dead, Jim.
  1916   _cfg     = (PhaseCFG*)0xdeadbeef;
  1917   _regalloc = (PhaseChaitin*)0xdeadbeef;
  1921 //------------------------------dump_asm---------------------------------------
  1922 // Dump formatted assembly
  1923 #ifndef PRODUCT
  1924 void Compile::dump_asm(int *pcs, uint pc_limit) {
  1925   bool cut_short = false;
  1926   tty->print_cr("#");
  1927   tty->print("#  ");  _tf->dump();  tty->cr();
  1928   tty->print_cr("#");
  1930   // For all blocks
  1931   int pc = 0x0;                 // Program counter
  1932   char starts_bundle = ' ';
  1933   _regalloc->dump_frame();
  1935   Node *n = NULL;
  1936   for( uint i=0; i<_cfg->_num_blocks; i++ ) {
  1937     if (VMThread::should_terminate()) { cut_short = true; break; }
  1938     Block *b = _cfg->_blocks[i];
  1939     if (b->is_connector() && !Verbose) continue;
  1940     n = b->_nodes[0];
  1941     if (pcs && n->_idx < pc_limit)
  1942       tty->print("%3.3x   ", pcs[n->_idx]);
  1943     else
  1944       tty->print("      ");
  1945     b->dump_head( &_cfg->_bbs );
  1946     if (b->is_connector()) {
  1947       tty->print_cr("        # Empty connector block");
  1948     } else if (b->num_preds() == 2 && b->pred(1)->is_CatchProj() && b->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
  1949       tty->print_cr("        # Block is sole successor of call");
  1952     // For all instructions
  1953     Node *delay = NULL;
  1954     for( uint j = 0; j<b->_nodes.size(); j++ ) {
  1955       if (VMThread::should_terminate()) { cut_short = true; break; }
  1956       n = b->_nodes[j];
  1957       if (valid_bundle_info(n)) {
  1958         Bundle *bundle = node_bundling(n);
  1959         if (bundle->used_in_unconditional_delay()) {
  1960           delay = n;
  1961           continue;
  1963         if (bundle->starts_bundle())
  1964           starts_bundle = '+';
  1967       if (WizardMode) n->dump();
  1969       if( !n->is_Region() &&    // Dont print in the Assembly
  1970           !n->is_Phi() &&       // a few noisely useless nodes
  1971           !n->is_Proj() &&
  1972           !n->is_MachTemp() &&
  1973           !n->is_SafePointScalarObject() &&
  1974           !n->is_Catch() &&     // Would be nice to print exception table targets
  1975           !n->is_MergeMem() &&  // Not very interesting
  1976           !n->is_top() &&       // Debug info table constants
  1977           !(n->is_Con() && !n->is_Mach())// Debug info table constants
  1978           ) {
  1979         if (pcs && n->_idx < pc_limit)
  1980           tty->print("%3.3x", pcs[n->_idx]);
  1981         else
  1982           tty->print("   ");
  1983         tty->print(" %c ", starts_bundle);
  1984         starts_bundle = ' ';
  1985         tty->print("\t");
  1986         n->format(_regalloc, tty);
  1987         tty->cr();
  1990       // If we have an instruction with a delay slot, and have seen a delay,
  1991       // then back up and print it
  1992       if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
  1993         assert(delay != NULL, "no unconditional delay instruction");
  1994         if (WizardMode) delay->dump();
  1996         if (node_bundling(delay)->starts_bundle())
  1997           starts_bundle = '+';
  1998         if (pcs && n->_idx < pc_limit)
  1999           tty->print("%3.3x", pcs[n->_idx]);
  2000         else
  2001           tty->print("   ");
  2002         tty->print(" %c ", starts_bundle);
  2003         starts_bundle = ' ';
  2004         tty->print("\t");
  2005         delay->format(_regalloc, tty);
  2006         tty->print_cr("");
  2007         delay = NULL;
  2010       // Dump the exception table as well
  2011       if( n->is_Catch() && (Verbose || WizardMode) ) {
  2012         // Print the exception table for this offset
  2013         _handler_table.print_subtable_for(pc);
  2017     if (pcs && n->_idx < pc_limit)
  2018       tty->print_cr("%3.3x", pcs[n->_idx]);
  2019     else
  2020       tty->print_cr("");
  2022     assert(cut_short || delay == NULL, "no unconditional delay branch");
  2024   } // End of per-block dump
  2025   tty->print_cr("");
  2027   if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
  2029 #endif
  2031 //------------------------------Final_Reshape_Counts---------------------------
  2032 // This class defines counters to help identify when a method
  2033 // may/must be executed using hardware with only 24-bit precision.
  2034 struct Final_Reshape_Counts : public StackObj {
  2035   int  _call_count;             // count non-inlined 'common' calls
  2036   int  _float_count;            // count float ops requiring 24-bit precision
  2037   int  _double_count;           // count double ops requiring more precision
  2038   int  _java_call_count;        // count non-inlined 'java' calls
  2039   int  _inner_loop_count;       // count loops which need alignment
  2040   VectorSet _visited;           // Visitation flags
  2041   Node_List _tests;             // Set of IfNodes & PCTableNodes
  2043   Final_Reshape_Counts() :
  2044     _call_count(0), _float_count(0), _double_count(0),
  2045     _java_call_count(0), _inner_loop_count(0),
  2046     _visited( Thread::current()->resource_area() ) { }
  2048   void inc_call_count  () { _call_count  ++; }
  2049   void inc_float_count () { _float_count ++; }
  2050   void inc_double_count() { _double_count++; }
  2051   void inc_java_call_count() { _java_call_count++; }
  2052   void inc_inner_loop_count() { _inner_loop_count++; }
  2054   int  get_call_count  () const { return _call_count  ; }
  2055   int  get_float_count () const { return _float_count ; }
  2056   int  get_double_count() const { return _double_count; }
  2057   int  get_java_call_count() const { return _java_call_count; }
  2058   int  get_inner_loop_count() const { return _inner_loop_count; }
  2059 };
  2061 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
  2062   ciInstanceKlass *k = tp->klass()->as_instance_klass();
  2063   // Make sure the offset goes inside the instance layout.
  2064   return k->contains_field_offset(tp->offset());
  2065   // Note that OffsetBot and OffsetTop are very negative.
  2068 // Eliminate trivially redundant StoreCMs and accumulate their
  2069 // precedence edges.
  2070 static void eliminate_redundant_card_marks(Node* n) {
  2071   assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
  2072   if (n->in(MemNode::Address)->outcnt() > 1) {
  2073     // There are multiple users of the same address so it might be
  2074     // possible to eliminate some of the StoreCMs
  2075     Node* mem = n->in(MemNode::Memory);
  2076     Node* adr = n->in(MemNode::Address);
  2077     Node* val = n->in(MemNode::ValueIn);
  2078     Node* prev = n;
  2079     bool done = false;
  2080     // Walk the chain of StoreCMs eliminating ones that match.  As
  2081     // long as it's a chain of single users then the optimization is
  2082     // safe.  Eliminating partially redundant StoreCMs would require
  2083     // cloning copies down the other paths.
  2084     while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
  2085       if (adr == mem->in(MemNode::Address) &&
  2086           val == mem->in(MemNode::ValueIn)) {
  2087         // redundant StoreCM
  2088         if (mem->req() > MemNode::OopStore) {
  2089           // Hasn't been processed by this code yet.
  2090           n->add_prec(mem->in(MemNode::OopStore));
  2091         } else {
  2092           // Already converted to precedence edge
  2093           for (uint i = mem->req(); i < mem->len(); i++) {
  2094             // Accumulate any precedence edges
  2095             if (mem->in(i) != NULL) {
  2096               n->add_prec(mem->in(i));
  2099           // Everything above this point has been processed.
  2100           done = true;
  2102         // Eliminate the previous StoreCM
  2103         prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
  2104         assert(mem->outcnt() == 0, "should be dead");
  2105         mem->disconnect_inputs(NULL);
  2106       } else {
  2107         prev = mem;
  2109       mem = prev->in(MemNode::Memory);
  2114 //------------------------------final_graph_reshaping_impl----------------------
  2115 // Implement items 1-5 from final_graph_reshaping below.
  2116 static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
  2118   if ( n->outcnt() == 0 ) return; // dead node
  2119   uint nop = n->Opcode();
  2121   // Check for 2-input instruction with "last use" on right input.
  2122   // Swap to left input.  Implements item (2).
  2123   if( n->req() == 3 &&          // two-input instruction
  2124       n->in(1)->outcnt() > 1 && // left use is NOT a last use
  2125       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
  2126       n->in(2)->outcnt() == 1 &&// right use IS a last use
  2127       !n->in(2)->is_Con() ) {   // right use is not a constant
  2128     // Check for commutative opcode
  2129     switch( nop ) {
  2130     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
  2131     case Op_MaxI:  case Op_MinI:
  2132     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
  2133     case Op_AndL:  case Op_XorL:  case Op_OrL:
  2134     case Op_AndI:  case Op_XorI:  case Op_OrI: {
  2135       // Move "last use" input to left by swapping inputs
  2136       n->swap_edges(1, 2);
  2137       break;
  2139     default:
  2140       break;
  2144 #ifdef ASSERT
  2145   if( n->is_Mem() ) {
  2146     Compile* C = Compile::current();
  2147     int alias_idx = C->get_alias_index(n->as_Mem()->adr_type());
  2148     assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
  2149             // oop will be recorded in oop map if load crosses safepoint
  2150             n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
  2151                              LoadNode::is_immutable_value(n->in(MemNode::Address))),
  2152             "raw memory operations should have control edge");
  2154 #endif
  2155   // Count FPU ops and common calls, implements item (3)
  2156   switch( nop ) {
  2157   // Count all float operations that may use FPU
  2158   case Op_AddF:
  2159   case Op_SubF:
  2160   case Op_MulF:
  2161   case Op_DivF:
  2162   case Op_NegF:
  2163   case Op_ModF:
  2164   case Op_ConvI2F:
  2165   case Op_ConF:
  2166   case Op_CmpF:
  2167   case Op_CmpF3:
  2168   // case Op_ConvL2F: // longs are split into 32-bit halves
  2169     frc.inc_float_count();
  2170     break;
  2172   case Op_ConvF2D:
  2173   case Op_ConvD2F:
  2174     frc.inc_float_count();
  2175     frc.inc_double_count();
  2176     break;
  2178   // Count all double operations that may use FPU
  2179   case Op_AddD:
  2180   case Op_SubD:
  2181   case Op_MulD:
  2182   case Op_DivD:
  2183   case Op_NegD:
  2184   case Op_ModD:
  2185   case Op_ConvI2D:
  2186   case Op_ConvD2I:
  2187   // case Op_ConvL2D: // handled by leaf call
  2188   // case Op_ConvD2L: // handled by leaf call
  2189   case Op_ConD:
  2190   case Op_CmpD:
  2191   case Op_CmpD3:
  2192     frc.inc_double_count();
  2193     break;
  2194   case Op_Opaque1:              // Remove Opaque Nodes before matching
  2195   case Op_Opaque2:              // Remove Opaque Nodes before matching
  2196     n->subsume_by(n->in(1));
  2197     break;
  2198   case Op_CallStaticJava:
  2199   case Op_CallJava:
  2200   case Op_CallDynamicJava:
  2201     frc.inc_java_call_count(); // Count java call site;
  2202   case Op_CallRuntime:
  2203   case Op_CallLeaf:
  2204   case Op_CallLeafNoFP: {
  2205     assert( n->is_Call(), "" );
  2206     CallNode *call = n->as_Call();
  2207     // Count call sites where the FP mode bit would have to be flipped.
  2208     // Do not count uncommon runtime calls:
  2209     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
  2210     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
  2211     if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
  2212       frc.inc_call_count();   // Count the call site
  2213     } else {                  // See if uncommon argument is shared
  2214       Node *n = call->in(TypeFunc::Parms);
  2215       int nop = n->Opcode();
  2216       // Clone shared simple arguments to uncommon calls, item (1).
  2217       if( n->outcnt() > 1 &&
  2218           !n->is_Proj() &&
  2219           nop != Op_CreateEx &&
  2220           nop != Op_CheckCastPP &&
  2221           nop != Op_DecodeN &&
  2222           !n->is_Mem() ) {
  2223         Node *x = n->clone();
  2224         call->set_req( TypeFunc::Parms, x );
  2227     break;
  2230   case Op_StoreD:
  2231   case Op_LoadD:
  2232   case Op_LoadD_unaligned:
  2233     frc.inc_double_count();
  2234     goto handle_mem;
  2235   case Op_StoreF:
  2236   case Op_LoadF:
  2237     frc.inc_float_count();
  2238     goto handle_mem;
  2240   case Op_StoreCM:
  2242       // Convert OopStore dependence into precedence edge
  2243       Node* prec = n->in(MemNode::OopStore);
  2244       n->del_req(MemNode::OopStore);
  2245       n->add_prec(prec);
  2246       eliminate_redundant_card_marks(n);
  2249     // fall through
  2251   case Op_StoreB:
  2252   case Op_StoreC:
  2253   case Op_StorePConditional:
  2254   case Op_StoreI:
  2255   case Op_StoreL:
  2256   case Op_StoreIConditional:
  2257   case Op_StoreLConditional:
  2258   case Op_CompareAndSwapI:
  2259   case Op_CompareAndSwapL:
  2260   case Op_CompareAndSwapP:
  2261   case Op_CompareAndSwapN:
  2262   case Op_StoreP:
  2263   case Op_StoreN:
  2264   case Op_LoadB:
  2265   case Op_LoadUB:
  2266   case Op_LoadUS:
  2267   case Op_LoadI:
  2268   case Op_LoadUI2L:
  2269   case Op_LoadKlass:
  2270   case Op_LoadNKlass:
  2271   case Op_LoadL:
  2272   case Op_LoadL_unaligned:
  2273   case Op_LoadPLocked:
  2274   case Op_LoadLLocked:
  2275   case Op_LoadP:
  2276   case Op_LoadN:
  2277   case Op_LoadRange:
  2278   case Op_LoadS: {
  2279   handle_mem:
  2280 #ifdef ASSERT
  2281     if( VerifyOptoOopOffsets ) {
  2282       assert( n->is_Mem(), "" );
  2283       MemNode *mem  = (MemNode*)n;
  2284       // Check to see if address types have grounded out somehow.
  2285       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
  2286       assert( !tp || oop_offset_is_sane(tp), "" );
  2288 #endif
  2289     break;
  2292   case Op_AddP: {               // Assert sane base pointers
  2293     Node *addp = n->in(AddPNode::Address);
  2294     assert( !addp->is_AddP() ||
  2295             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
  2296             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
  2297             "Base pointers must match" );
  2298 #ifdef _LP64
  2299     if (UseCompressedOops &&
  2300         addp->Opcode() == Op_ConP &&
  2301         addp == n->in(AddPNode::Base) &&
  2302         n->in(AddPNode::Offset)->is_Con()) {
  2303       // Use addressing with narrow klass to load with offset on x86.
  2304       // On sparc loading 32-bits constant and decoding it have less
  2305       // instructions (4) then load 64-bits constant (7).
  2306       // Do this transformation here since IGVN will convert ConN back to ConP.
  2307       const Type* t = addp->bottom_type();
  2308       if (t->isa_oopptr()) {
  2309         Node* nn = NULL;
  2311         // Look for existing ConN node of the same exact type.
  2312         Compile* C = Compile::current();
  2313         Node* r  = C->root();
  2314         uint cnt = r->outcnt();
  2315         for (uint i = 0; i < cnt; i++) {
  2316           Node* m = r->raw_out(i);
  2317           if (m!= NULL && m->Opcode() == Op_ConN &&
  2318               m->bottom_type()->make_ptr() == t) {
  2319             nn = m;
  2320             break;
  2323         if (nn != NULL) {
  2324           // Decode a narrow oop to match address
  2325           // [R12 + narrow_oop_reg<<3 + offset]
  2326           nn = new (C,  2) DecodeNNode(nn, t);
  2327           n->set_req(AddPNode::Base, nn);
  2328           n->set_req(AddPNode::Address, nn);
  2329           if (addp->outcnt() == 0) {
  2330             addp->disconnect_inputs(NULL);
  2335 #endif
  2336     break;
  2339 #ifdef _LP64
  2340   case Op_CastPP:
  2341     if (n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
  2342       Compile* C = Compile::current();
  2343       Node* in1 = n->in(1);
  2344       const Type* t = n->bottom_type();
  2345       Node* new_in1 = in1->clone();
  2346       new_in1->as_DecodeN()->set_type(t);
  2348       if (!Matcher::narrow_oop_use_complex_address()) {
  2349         //
  2350         // x86, ARM and friends can handle 2 adds in addressing mode
  2351         // and Matcher can fold a DecodeN node into address by using
  2352         // a narrow oop directly and do implicit NULL check in address:
  2353         //
  2354         // [R12 + narrow_oop_reg<<3 + offset]
  2355         // NullCheck narrow_oop_reg
  2356         //
  2357         // On other platforms (Sparc) we have to keep new DecodeN node and
  2358         // use it to do implicit NULL check in address:
  2359         //
  2360         // decode_not_null narrow_oop_reg, base_reg
  2361         // [base_reg + offset]
  2362         // NullCheck base_reg
  2363         //
  2364         // Pin the new DecodeN node to non-null path on these platform (Sparc)
  2365         // to keep the information to which NULL check the new DecodeN node
  2366         // corresponds to use it as value in implicit_null_check().
  2367         //
  2368         new_in1->set_req(0, n->in(0));
  2371       n->subsume_by(new_in1);
  2372       if (in1->outcnt() == 0) {
  2373         in1->disconnect_inputs(NULL);
  2376     break;
  2378   case Op_CmpP:
  2379     // Do this transformation here to preserve CmpPNode::sub() and
  2380     // other TypePtr related Ideal optimizations (for example, ptr nullness).
  2381     if (n->in(1)->is_DecodeN() || n->in(2)->is_DecodeN()) {
  2382       Node* in1 = n->in(1);
  2383       Node* in2 = n->in(2);
  2384       if (!in1->is_DecodeN()) {
  2385         in2 = in1;
  2386         in1 = n->in(2);
  2388       assert(in1->is_DecodeN(), "sanity");
  2390       Compile* C = Compile::current();
  2391       Node* new_in2 = NULL;
  2392       if (in2->is_DecodeN()) {
  2393         new_in2 = in2->in(1);
  2394       } else if (in2->Opcode() == Op_ConP) {
  2395         const Type* t = in2->bottom_type();
  2396         if (t == TypePtr::NULL_PTR) {
  2397           // Don't convert CmpP null check into CmpN if compressed
  2398           // oops implicit null check is not generated.
  2399           // This will allow to generate normal oop implicit null check.
  2400           if (Matcher::gen_narrow_oop_implicit_null_checks())
  2401             new_in2 = ConNode::make(C, TypeNarrowOop::NULL_PTR);
  2402           //
  2403           // This transformation together with CastPP transformation above
  2404           // will generated code for implicit NULL checks for compressed oops.
  2405           //
  2406           // The original code after Optimize()
  2407           //
  2408           //    LoadN memory, narrow_oop_reg
  2409           //    decode narrow_oop_reg, base_reg
  2410           //    CmpP base_reg, NULL
  2411           //    CastPP base_reg // NotNull
  2412           //    Load [base_reg + offset], val_reg
  2413           //
  2414           // after these transformations will be
  2415           //
  2416           //    LoadN memory, narrow_oop_reg
  2417           //    CmpN narrow_oop_reg, NULL
  2418           //    decode_not_null narrow_oop_reg, base_reg
  2419           //    Load [base_reg + offset], val_reg
  2420           //
  2421           // and the uncommon path (== NULL) will use narrow_oop_reg directly
  2422           // since narrow oops can be used in debug info now (see the code in
  2423           // final_graph_reshaping_walk()).
  2424           //
  2425           // At the end the code will be matched to
  2426           // on x86:
  2427           //
  2428           //    Load_narrow_oop memory, narrow_oop_reg
  2429           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
  2430           //    NullCheck narrow_oop_reg
  2431           //
  2432           // and on sparc:
  2433           //
  2434           //    Load_narrow_oop memory, narrow_oop_reg
  2435           //    decode_not_null narrow_oop_reg, base_reg
  2436           //    Load [base_reg + offset], val_reg
  2437           //    NullCheck base_reg
  2438           //
  2439         } else if (t->isa_oopptr()) {
  2440           new_in2 = ConNode::make(C, t->make_narrowoop());
  2443       if (new_in2 != NULL) {
  2444         Node* cmpN = new (C, 3) CmpNNode(in1->in(1), new_in2);
  2445         n->subsume_by( cmpN );
  2446         if (in1->outcnt() == 0) {
  2447           in1->disconnect_inputs(NULL);
  2449         if (in2->outcnt() == 0) {
  2450           in2->disconnect_inputs(NULL);
  2454     break;
  2456   case Op_DecodeN:
  2457     assert(!n->in(1)->is_EncodeP(), "should be optimized out");
  2458     // DecodeN could be pinned when it can't be fold into
  2459     // an address expression, see the code for Op_CastPP above.
  2460     assert(n->in(0) == NULL || !Matcher::narrow_oop_use_complex_address(), "no control");
  2461     break;
  2463   case Op_EncodeP: {
  2464     Node* in1 = n->in(1);
  2465     if (in1->is_DecodeN()) {
  2466       n->subsume_by(in1->in(1));
  2467     } else if (in1->Opcode() == Op_ConP) {
  2468       Compile* C = Compile::current();
  2469       const Type* t = in1->bottom_type();
  2470       if (t == TypePtr::NULL_PTR) {
  2471         n->subsume_by(ConNode::make(C, TypeNarrowOop::NULL_PTR));
  2472       } else if (t->isa_oopptr()) {
  2473         n->subsume_by(ConNode::make(C, t->make_narrowoop()));
  2476     if (in1->outcnt() == 0) {
  2477       in1->disconnect_inputs(NULL);
  2479     break;
  2482   case Op_Proj: {
  2483     if (OptimizeStringConcat) {
  2484       ProjNode* p = n->as_Proj();
  2485       if (p->_is_io_use) {
  2486         // Separate projections were used for the exception path which
  2487         // are normally removed by a late inline.  If it wasn't inlined
  2488         // then they will hang around and should just be replaced with
  2489         // the original one.
  2490         Node* proj = NULL;
  2491         // Replace with just one
  2492         for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
  2493           Node *use = i.get();
  2494           if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
  2495             proj = use;
  2496             break;
  2499         assert(p != NULL, "must be found");
  2500         p->subsume_by(proj);
  2503     break;
  2506   case Op_Phi:
  2507     if (n->as_Phi()->bottom_type()->isa_narrowoop()) {
  2508       // The EncodeP optimization may create Phi with the same edges
  2509       // for all paths. It is not handled well by Register Allocator.
  2510       Node* unique_in = n->in(1);
  2511       assert(unique_in != NULL, "");
  2512       uint cnt = n->req();
  2513       for (uint i = 2; i < cnt; i++) {
  2514         Node* m = n->in(i);
  2515         assert(m != NULL, "");
  2516         if (unique_in != m)
  2517           unique_in = NULL;
  2519       if (unique_in != NULL) {
  2520         n->subsume_by(unique_in);
  2523     break;
  2525 #endif
  2527   case Op_ModI:
  2528     if (UseDivMod) {
  2529       // Check if a%b and a/b both exist
  2530       Node* d = n->find_similar(Op_DivI);
  2531       if (d) {
  2532         // Replace them with a fused divmod if supported
  2533         Compile* C = Compile::current();
  2534         if (Matcher::has_match_rule(Op_DivModI)) {
  2535           DivModINode* divmod = DivModINode::make(C, n);
  2536           d->subsume_by(divmod->div_proj());
  2537           n->subsume_by(divmod->mod_proj());
  2538         } else {
  2539           // replace a%b with a-((a/b)*b)
  2540           Node* mult = new (C, 3) MulINode(d, d->in(2));
  2541           Node* sub  = new (C, 3) SubINode(d->in(1), mult);
  2542           n->subsume_by( sub );
  2546     break;
  2548   case Op_ModL:
  2549     if (UseDivMod) {
  2550       // Check if a%b and a/b both exist
  2551       Node* d = n->find_similar(Op_DivL);
  2552       if (d) {
  2553         // Replace them with a fused divmod if supported
  2554         Compile* C = Compile::current();
  2555         if (Matcher::has_match_rule(Op_DivModL)) {
  2556           DivModLNode* divmod = DivModLNode::make(C, n);
  2557           d->subsume_by(divmod->div_proj());
  2558           n->subsume_by(divmod->mod_proj());
  2559         } else {
  2560           // replace a%b with a-((a/b)*b)
  2561           Node* mult = new (C, 3) MulLNode(d, d->in(2));
  2562           Node* sub  = new (C, 3) SubLNode(d->in(1), mult);
  2563           n->subsume_by( sub );
  2567     break;
  2569   case Op_Load16B:
  2570   case Op_Load8B:
  2571   case Op_Load4B:
  2572   case Op_Load8S:
  2573   case Op_Load4S:
  2574   case Op_Load2S:
  2575   case Op_Load8C:
  2576   case Op_Load4C:
  2577   case Op_Load2C:
  2578   case Op_Load4I:
  2579   case Op_Load2I:
  2580   case Op_Load2L:
  2581   case Op_Load4F:
  2582   case Op_Load2F:
  2583   case Op_Load2D:
  2584   case Op_Store16B:
  2585   case Op_Store8B:
  2586   case Op_Store4B:
  2587   case Op_Store8C:
  2588   case Op_Store4C:
  2589   case Op_Store2C:
  2590   case Op_Store4I:
  2591   case Op_Store2I:
  2592   case Op_Store2L:
  2593   case Op_Store4F:
  2594   case Op_Store2F:
  2595   case Op_Store2D:
  2596     break;
  2598   case Op_PackB:
  2599   case Op_PackS:
  2600   case Op_PackC:
  2601   case Op_PackI:
  2602   case Op_PackF:
  2603   case Op_PackL:
  2604   case Op_PackD:
  2605     if (n->req()-1 > 2) {
  2606       // Replace many operand PackNodes with a binary tree for matching
  2607       PackNode* p = (PackNode*) n;
  2608       Node* btp = p->binaryTreePack(Compile::current(), 1, n->req());
  2609       n->subsume_by(btp);
  2611     break;
  2612   case Op_Loop:
  2613   case Op_CountedLoop:
  2614     if (n->as_Loop()->is_inner_loop()) {
  2615       frc.inc_inner_loop_count();
  2617     break;
  2618   case Op_LShiftI:
  2619   case Op_RShiftI:
  2620   case Op_URShiftI:
  2621   case Op_LShiftL:
  2622   case Op_RShiftL:
  2623   case Op_URShiftL:
  2624     if (Matcher::need_masked_shift_count) {
  2625       // The cpu's shift instructions don't restrict the count to the
  2626       // lower 5/6 bits. We need to do the masking ourselves.
  2627       Node* in2 = n->in(2);
  2628       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
  2629       const TypeInt* t = in2->find_int_type();
  2630       if (t != NULL && t->is_con()) {
  2631         juint shift = t->get_con();
  2632         if (shift > mask) { // Unsigned cmp
  2633           Compile* C = Compile::current();
  2634           n->set_req(2, ConNode::make(C, TypeInt::make(shift & mask)));
  2636       } else {
  2637         if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
  2638           Compile* C = Compile::current();
  2639           Node* shift = new (C, 3) AndINode(in2, ConNode::make(C, TypeInt::make(mask)));
  2640           n->set_req(2, shift);
  2643       if (in2->outcnt() == 0) { // Remove dead node
  2644         in2->disconnect_inputs(NULL);
  2647     break;
  2648   default:
  2649     assert( !n->is_Call(), "" );
  2650     assert( !n->is_Mem(), "" );
  2651     break;
  2654   // Collect CFG split points
  2655   if (n->is_MultiBranch())
  2656     frc._tests.push(n);
  2659 //------------------------------final_graph_reshaping_walk---------------------
  2660 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
  2661 // requires that the walk visits a node's inputs before visiting the node.
  2662 static void final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
  2663   ResourceArea *area = Thread::current()->resource_area();
  2664   Unique_Node_List sfpt(area);
  2666   frc._visited.set(root->_idx); // first, mark node as visited
  2667   uint cnt = root->req();
  2668   Node *n = root;
  2669   uint  i = 0;
  2670   while (true) {
  2671     if (i < cnt) {
  2672       // Place all non-visited non-null inputs onto stack
  2673       Node* m = n->in(i);
  2674       ++i;
  2675       if (m != NULL && !frc._visited.test_set(m->_idx)) {
  2676         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL)
  2677           sfpt.push(m);
  2678         cnt = m->req();
  2679         nstack.push(n, i); // put on stack parent and next input's index
  2680         n = m;
  2681         i = 0;
  2683     } else {
  2684       // Now do post-visit work
  2685       final_graph_reshaping_impl( n, frc );
  2686       if (nstack.is_empty())
  2687         break;             // finished
  2688       n = nstack.node();   // Get node from stack
  2689       cnt = n->req();
  2690       i = nstack.index();
  2691       nstack.pop();        // Shift to the next node on stack
  2695   // Skip next transformation if compressed oops are not used.
  2696   if (!UseCompressedOops || !Matcher::gen_narrow_oop_implicit_null_checks())
  2697     return;
  2699   // Go over safepoints nodes to skip DecodeN nodes for debug edges.
  2700   // It could be done for an uncommon traps or any safepoints/calls
  2701   // if the DecodeN node is referenced only in a debug info.
  2702   while (sfpt.size() > 0) {
  2703     n = sfpt.pop();
  2704     JVMState *jvms = n->as_SafePoint()->jvms();
  2705     assert(jvms != NULL, "sanity");
  2706     int start = jvms->debug_start();
  2707     int end   = n->req();
  2708     bool is_uncommon = (n->is_CallStaticJava() &&
  2709                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
  2710     for (int j = start; j < end; j++) {
  2711       Node* in = n->in(j);
  2712       if (in->is_DecodeN()) {
  2713         bool safe_to_skip = true;
  2714         if (!is_uncommon ) {
  2715           // Is it safe to skip?
  2716           for (uint i = 0; i < in->outcnt(); i++) {
  2717             Node* u = in->raw_out(i);
  2718             if (!u->is_SafePoint() ||
  2719                  u->is_Call() && u->as_Call()->has_non_debug_use(n)) {
  2720               safe_to_skip = false;
  2724         if (safe_to_skip) {
  2725           n->set_req(j, in->in(1));
  2727         if (in->outcnt() == 0) {
  2728           in->disconnect_inputs(NULL);
  2735 //------------------------------final_graph_reshaping--------------------------
  2736 // Final Graph Reshaping.
  2737 //
  2738 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
  2739 //     and not commoned up and forced early.  Must come after regular
  2740 //     optimizations to avoid GVN undoing the cloning.  Clone constant
  2741 //     inputs to Loop Phis; these will be split by the allocator anyways.
  2742 //     Remove Opaque nodes.
  2743 // (2) Move last-uses by commutative operations to the left input to encourage
  2744 //     Intel update-in-place two-address operations and better register usage
  2745 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
  2746 //     calls canonicalizing them back.
  2747 // (3) Count the number of double-precision FP ops, single-precision FP ops
  2748 //     and call sites.  On Intel, we can get correct rounding either by
  2749 //     forcing singles to memory (requires extra stores and loads after each
  2750 //     FP bytecode) or we can set a rounding mode bit (requires setting and
  2751 //     clearing the mode bit around call sites).  The mode bit is only used
  2752 //     if the relative frequency of single FP ops to calls is low enough.
  2753 //     This is a key transform for SPEC mpeg_audio.
  2754 // (4) Detect infinite loops; blobs of code reachable from above but not
  2755 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
  2756 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
  2757 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
  2758 //     Detection is by looking for IfNodes where only 1 projection is
  2759 //     reachable from below or CatchNodes missing some targets.
  2760 // (5) Assert for insane oop offsets in debug mode.
  2762 bool Compile::final_graph_reshaping() {
  2763   // an infinite loop may have been eliminated by the optimizer,
  2764   // in which case the graph will be empty.
  2765   if (root()->req() == 1) {
  2766     record_method_not_compilable("trivial infinite loop");
  2767     return true;
  2770   Final_Reshape_Counts frc;
  2772   // Visit everybody reachable!
  2773   // Allocate stack of size C->unique()/2 to avoid frequent realloc
  2774   Node_Stack nstack(unique() >> 1);
  2775   final_graph_reshaping_walk(nstack, root(), frc);
  2777   // Check for unreachable (from below) code (i.e., infinite loops).
  2778   for( uint i = 0; i < frc._tests.size(); i++ ) {
  2779     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
  2780     // Get number of CFG targets.
  2781     // Note that PCTables include exception targets after calls.
  2782     uint required_outcnt = n->required_outcnt();
  2783     if (n->outcnt() != required_outcnt) {
  2784       // Check for a few special cases.  Rethrow Nodes never take the
  2785       // 'fall-thru' path, so expected kids is 1 less.
  2786       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
  2787         if (n->in(0)->in(0)->is_Call()) {
  2788           CallNode *call = n->in(0)->in(0)->as_Call();
  2789           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
  2790             required_outcnt--;      // Rethrow always has 1 less kid
  2791           } else if (call->req() > TypeFunc::Parms &&
  2792                      call->is_CallDynamicJava()) {
  2793             // Check for null receiver. In such case, the optimizer has
  2794             // detected that the virtual call will always result in a null
  2795             // pointer exception. The fall-through projection of this CatchNode
  2796             // will not be populated.
  2797             Node *arg0 = call->in(TypeFunc::Parms);
  2798             if (arg0->is_Type() &&
  2799                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
  2800               required_outcnt--;
  2802           } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
  2803                      call->req() > TypeFunc::Parms+1 &&
  2804                      call->is_CallStaticJava()) {
  2805             // Check for negative array length. In such case, the optimizer has
  2806             // detected that the allocation attempt will always result in an
  2807             // exception. There is no fall-through projection of this CatchNode .
  2808             Node *arg1 = call->in(TypeFunc::Parms+1);
  2809             if (arg1->is_Type() &&
  2810                 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
  2811               required_outcnt--;
  2816       // Recheck with a better notion of 'required_outcnt'
  2817       if (n->outcnt() != required_outcnt) {
  2818         record_method_not_compilable("malformed control flow");
  2819         return true;            // Not all targets reachable!
  2822     // Check that I actually visited all kids.  Unreached kids
  2823     // must be infinite loops.
  2824     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
  2825       if (!frc._visited.test(n->fast_out(j)->_idx)) {
  2826         record_method_not_compilable("infinite loop");
  2827         return true;            // Found unvisited kid; must be unreach
  2831   // If original bytecodes contained a mixture of floats and doubles
  2832   // check if the optimizer has made it homogenous, item (3).
  2833   if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
  2834       frc.get_float_count() > 32 &&
  2835       frc.get_double_count() == 0 &&
  2836       (10 * frc.get_call_count() < frc.get_float_count()) ) {
  2837     set_24_bit_selection_and_mode( false,  true );
  2840   set_java_calls(frc.get_java_call_count());
  2841   set_inner_loops(frc.get_inner_loop_count());
  2843   // No infinite loops, no reason to bail out.
  2844   return false;
  2847 //-----------------------------too_many_traps----------------------------------
  2848 // Report if there are too many traps at the current method and bci.
  2849 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
  2850 bool Compile::too_many_traps(ciMethod* method,
  2851                              int bci,
  2852                              Deoptimization::DeoptReason reason) {
  2853   ciMethodData* md = method->method_data();
  2854   if (md->is_empty()) {
  2855     // Assume the trap has not occurred, or that it occurred only
  2856     // because of a transient condition during start-up in the interpreter.
  2857     return false;
  2859   if (md->has_trap_at(bci, reason) != 0) {
  2860     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
  2861     // Also, if there are multiple reasons, or if there is no per-BCI record,
  2862     // assume the worst.
  2863     if (log())
  2864       log()->elem("observe trap='%s' count='%d'",
  2865                   Deoptimization::trap_reason_name(reason),
  2866                   md->trap_count(reason));
  2867     return true;
  2868   } else {
  2869     // Ignore method/bci and see if there have been too many globally.
  2870     return too_many_traps(reason, md);
  2874 // Less-accurate variant which does not require a method and bci.
  2875 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
  2876                              ciMethodData* logmd) {
  2877  if (trap_count(reason) >= (uint)PerMethodTrapLimit) {
  2878     // Too many traps globally.
  2879     // Note that we use cumulative trap_count, not just md->trap_count.
  2880     if (log()) {
  2881       int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
  2882       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
  2883                   Deoptimization::trap_reason_name(reason),
  2884                   mcount, trap_count(reason));
  2886     return true;
  2887   } else {
  2888     // The coast is clear.
  2889     return false;
  2893 //--------------------------too_many_recompiles--------------------------------
  2894 // Report if there are too many recompiles at the current method and bci.
  2895 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
  2896 // Is not eager to return true, since this will cause the compiler to use
  2897 // Action_none for a trap point, to avoid too many recompilations.
  2898 bool Compile::too_many_recompiles(ciMethod* method,
  2899                                   int bci,
  2900                                   Deoptimization::DeoptReason reason) {
  2901   ciMethodData* md = method->method_data();
  2902   if (md->is_empty()) {
  2903     // Assume the trap has not occurred, or that it occurred only
  2904     // because of a transient condition during start-up in the interpreter.
  2905     return false;
  2907   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
  2908   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
  2909   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
  2910   Deoptimization::DeoptReason per_bc_reason
  2911     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
  2912   if ((per_bc_reason == Deoptimization::Reason_none
  2913        || md->has_trap_at(bci, reason) != 0)
  2914       // The trap frequency measure we care about is the recompile count:
  2915       && md->trap_recompiled_at(bci)
  2916       && md->overflow_recompile_count() >= bc_cutoff) {
  2917     // Do not emit a trap here if it has already caused recompilations.
  2918     // Also, if there are multiple reasons, or if there is no per-BCI record,
  2919     // assume the worst.
  2920     if (log())
  2921       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
  2922                   Deoptimization::trap_reason_name(reason),
  2923                   md->trap_count(reason),
  2924                   md->overflow_recompile_count());
  2925     return true;
  2926   } else if (trap_count(reason) != 0
  2927              && decompile_count() >= m_cutoff) {
  2928     // Too many recompiles globally, and we have seen this sort of trap.
  2929     // Use cumulative decompile_count, not just md->decompile_count.
  2930     if (log())
  2931       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
  2932                   Deoptimization::trap_reason_name(reason),
  2933                   md->trap_count(reason), trap_count(reason),
  2934                   md->decompile_count(), decompile_count());
  2935     return true;
  2936   } else {
  2937     // The coast is clear.
  2938     return false;
  2943 #ifndef PRODUCT
  2944 //------------------------------verify_graph_edges---------------------------
  2945 // Walk the Graph and verify that there is a one-to-one correspondence
  2946 // between Use-Def edges and Def-Use edges in the graph.
  2947 void Compile::verify_graph_edges(bool no_dead_code) {
  2948   if (VerifyGraphEdges) {
  2949     ResourceArea *area = Thread::current()->resource_area();
  2950     Unique_Node_List visited(area);
  2951     // Call recursive graph walk to check edges
  2952     _root->verify_edges(visited);
  2953     if (no_dead_code) {
  2954       // Now make sure that no visited node is used by an unvisited node.
  2955       bool dead_nodes = 0;
  2956       Unique_Node_List checked(area);
  2957       while (visited.size() > 0) {
  2958         Node* n = visited.pop();
  2959         checked.push(n);
  2960         for (uint i = 0; i < n->outcnt(); i++) {
  2961           Node* use = n->raw_out(i);
  2962           if (checked.member(use))  continue;  // already checked
  2963           if (visited.member(use))  continue;  // already in the graph
  2964           if (use->is_Con())        continue;  // a dead ConNode is OK
  2965           // At this point, we have found a dead node which is DU-reachable.
  2966           if (dead_nodes++ == 0)
  2967             tty->print_cr("*** Dead nodes reachable via DU edges:");
  2968           use->dump(2);
  2969           tty->print_cr("---");
  2970           checked.push(use);  // No repeats; pretend it is now checked.
  2973       assert(dead_nodes == 0, "using nodes must be reachable from root");
  2977 #endif
  2979 // The Compile object keeps track of failure reasons separately from the ciEnv.
  2980 // This is required because there is not quite a 1-1 relation between the
  2981 // ciEnv and its compilation task and the Compile object.  Note that one
  2982 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
  2983 // to backtrack and retry without subsuming loads.  Other than this backtracking
  2984 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
  2985 // by the logic in C2Compiler.
  2986 void Compile::record_failure(const char* reason) {
  2987   if (log() != NULL) {
  2988     log()->elem("failure reason='%s' phase='compile'", reason);
  2990   if (_failure_reason == NULL) {
  2991     // Record the first failure reason.
  2992     _failure_reason = reason;
  2994   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
  2995     C->print_method(_failure_reason);
  2997   _root = NULL;  // flush the graph, too
  3000 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator, bool dolog)
  3001   : TraceTime(NULL, accumulator, false NOT_PRODUCT( || TimeCompiler ), false)
  3003   if (dolog) {
  3004     C = Compile::current();
  3005     _log = C->log();
  3006   } else {
  3007     C = NULL;
  3008     _log = NULL;
  3010   if (_log != NULL) {
  3011     _log->begin_head("phase name='%s' nodes='%d'", name, C->unique());
  3012     _log->stamp();
  3013     _log->end_head();
  3017 Compile::TracePhase::~TracePhase() {
  3018   if (_log != NULL) {
  3019     _log->done("phase nodes='%d'", C->unique());
  3023 //=============================================================================
  3024 // Two Constant's are equal when the type and the value are equal.
  3025 bool Compile::Constant::operator==(const Constant& other) {
  3026   if (type()          != other.type()         )  return false;
  3027   if (can_be_reused() != other.can_be_reused())  return false;
  3028   // For floating point values we compare the bit pattern.
  3029   switch (type()) {
  3030   case T_FLOAT:   return (_value.i == other._value.i);
  3031   case T_LONG:
  3032   case T_DOUBLE:  return (_value.j == other._value.j);
  3033   case T_OBJECT:
  3034   case T_ADDRESS: return (_value.l == other._value.l);
  3035   case T_VOID:    return (_value.l == other._value.l);  // jump-table entries
  3036   default: ShouldNotReachHere();
  3038   return false;
  3041 // Emit constants grouped in the following order:
  3042 static BasicType type_order[] = {
  3043   T_FLOAT,    // 32-bit
  3044   T_OBJECT,   // 32 or 64-bit
  3045   T_ADDRESS,  // 32 or 64-bit
  3046   T_DOUBLE,   // 64-bit
  3047   T_LONG,     // 64-bit
  3048   T_VOID,     // 32 or 64-bit (jump-tables are at the end of the constant table for code emission reasons)
  3049   T_ILLEGAL
  3050 };
  3052 static int type_to_size_in_bytes(BasicType t) {
  3053   switch (t) {
  3054   case T_LONG:    return sizeof(jlong  );
  3055   case T_FLOAT:   return sizeof(jfloat );
  3056   case T_DOUBLE:  return sizeof(jdouble);
  3057     // We use T_VOID as marker for jump-table entries (labels) which
  3058     // need an interal word relocation.
  3059   case T_VOID:
  3060   case T_ADDRESS:
  3061   case T_OBJECT:  return sizeof(jobject);
  3064   ShouldNotReachHere();
  3065   return -1;
  3068 void Compile::ConstantTable::calculate_offsets_and_size() {
  3069   int size = 0;
  3070   for (int t = 0; type_order[t] != T_ILLEGAL; t++) {
  3071     BasicType type = type_order[t];
  3073     for (int i = 0; i < _constants.length(); i++) {
  3074       Constant con = _constants.at(i);
  3075       if (con.type() != type)  continue;  // Skip other types.
  3077       // Align size for type.
  3078       int typesize = type_to_size_in_bytes(con.type());
  3079       size = align_size_up(size, typesize);
  3081       // Set offset.
  3082       con.set_offset(size);
  3083       _constants.at_put(i, con);
  3085       // Add type size.
  3086       size = size + typesize;
  3090   // Align size up to the next section start (which is insts; see
  3091   // CodeBuffer::align_at_start).
  3092   assert(_size == -1, "already set?");
  3093   _size = align_size_up(size, CodeEntryAlignment);
  3095   if (Matcher::constant_table_absolute_addressing) {
  3096     set_table_base_offset(0);  // No table base offset required
  3097   } else {
  3098     if (UseRDPCForConstantTableBase) {
  3099       // table base offset is set in MachConstantBaseNode::emit
  3100     } else {
  3101       // When RDPC is not used, the table base is set into the middle of
  3102       // the constant table.
  3103       int half_size = _size / 2;
  3104       assert(half_size * 2 == _size, "sanity");
  3105       set_table_base_offset(-half_size);
  3110 void Compile::ConstantTable::emit(CodeBuffer& cb) {
  3111   MacroAssembler _masm(&cb);
  3112   for (int t = 0; type_order[t] != T_ILLEGAL; t++) {
  3113     BasicType type = type_order[t];
  3115     for (int i = 0; i < _constants.length(); i++) {
  3116       Constant con = _constants.at(i);
  3117       if (con.type() != type)  continue;  // Skip other types.
  3119       address constant_addr;
  3120       switch (con.type()) {
  3121       case T_LONG:   constant_addr = _masm.long_constant(  con.get_jlong()  ); break;
  3122       case T_FLOAT:  constant_addr = _masm.float_constant( con.get_jfloat() ); break;
  3123       case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
  3124       case T_OBJECT: {
  3125         jobject obj = con.get_jobject();
  3126         int oop_index = _masm.oop_recorder()->find_index(obj);
  3127         constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
  3128         break;
  3130       case T_ADDRESS: {
  3131         address addr = (address) con.get_jobject();
  3132         constant_addr = _masm.address_constant(addr);
  3133         break;
  3135       // We use T_VOID as marker for jump-table entries (labels) which
  3136       // need an interal word relocation.
  3137       case T_VOID: {
  3138         // Write a dummy word.  The real value is filled in later
  3139         // in fill_jump_table_in_constant_table.
  3140         address addr = (address) con.get_jobject();
  3141         constant_addr = _masm.address_constant(addr);
  3142         break;
  3144       default: ShouldNotReachHere();
  3146       assert(constant_addr != NULL, "consts section too small");
  3147       assert((constant_addr - _masm.code()->consts()->start()) == con.offset(), err_msg("must be: %d == %d", constant_addr - _masm.code()->consts()->start(), con.offset()));
  3152 int Compile::ConstantTable::find_offset(Constant& con) const {
  3153   int idx = _constants.find(con);
  3154   assert(idx != -1, "constant must be in constant table");
  3155   int offset = _constants.at(idx).offset();
  3156   assert(offset != -1, "constant table not emitted yet?");
  3157   return offset;
  3160 void Compile::ConstantTable::add(Constant& con) {
  3161   if (con.can_be_reused()) {
  3162     int idx = _constants.find(con);
  3163     if (idx != -1 && _constants.at(idx).can_be_reused()) {
  3164       return;
  3167   (void) _constants.append(con);
  3170 Compile::Constant Compile::ConstantTable::add(BasicType type, jvalue value) {
  3171   Constant con(type, value);
  3172   add(con);
  3173   return con;
  3176 Compile::Constant Compile::ConstantTable::add(MachOper* oper) {
  3177   jvalue value;
  3178   BasicType type = oper->type()->basic_type();
  3179   switch (type) {
  3180   case T_LONG:    value.j = oper->constantL(); break;
  3181   case T_FLOAT:   value.f = oper->constantF(); break;
  3182   case T_DOUBLE:  value.d = oper->constantD(); break;
  3183   case T_OBJECT:
  3184   case T_ADDRESS: value.l = (jobject) oper->constant(); break;
  3185   default: ShouldNotReachHere();
  3187   return add(type, value);
  3190 Compile::Constant Compile::ConstantTable::allocate_jump_table(MachConstantNode* n) {
  3191   jvalue value;
  3192   // We can use the node pointer here to identify the right jump-table
  3193   // as this method is called from Compile::Fill_buffer right before
  3194   // the MachNodes are emitted and the jump-table is filled (means the
  3195   // MachNode pointers do not change anymore).
  3196   value.l = (jobject) n;
  3197   Constant con(T_VOID, value, false);  // Labels of a jump-table cannot be reused.
  3198   for (uint i = 0; i < n->outcnt(); i++) {
  3199     add(con);
  3201   return con;
  3204 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
  3205   // If called from Compile::scratch_emit_size do nothing.
  3206   if (Compile::current()->in_scratch_emit_size())  return;
  3208   assert(labels.is_nonempty(), "must be");
  3209   assert((uint) labels.length() == n->outcnt(), err_msg("must be equal: %d == %d", labels.length(), n->outcnt()));
  3211   // Since MachConstantNode::constant_offset() also contains
  3212   // table_base_offset() we need to subtract the table_base_offset()
  3213   // to get the plain offset into the constant table.
  3214   int offset = n->constant_offset() - table_base_offset();
  3216   MacroAssembler _masm(&cb);
  3217   address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
  3219   for (int i = 0; i < labels.length(); i++) {
  3220     address* constant_addr = &jump_table_base[i];
  3221     assert(*constant_addr == (address) n, "all jump-table entries must contain node pointer");
  3222     *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
  3223     cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);

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