src/share/vm/opto/compile.cpp

Thu, 21 Nov 2013 12:30:35 -0800

author
kvn
date
Thu, 21 Nov 2013 12:30:35 -0800
changeset 6485
da862781b584
parent 6478
044b28168e20
parent 6071
613e6a6fc328
child 6488
4cdf4f71177d
permissions
-rw-r--r--

Merge

     1 /*
     2  * Copyright (c) 1997, 2013, 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/macroAssembler.hpp"
    27 #include "asm/macroAssembler.inline.hpp"
    28 #include "classfile/systemDictionary.hpp"
    29 #include "code/exceptionHandlerTable.hpp"
    30 #include "code/nmethod.hpp"
    31 #include "compiler/compileLog.hpp"
    32 #include "compiler/disassembler.hpp"
    33 #include "compiler/oopMap.hpp"
    34 #include "opto/addnode.hpp"
    35 #include "opto/block.hpp"
    36 #include "opto/c2compiler.hpp"
    37 #include "opto/callGenerator.hpp"
    38 #include "opto/callnode.hpp"
    39 #include "opto/cfgnode.hpp"
    40 #include "opto/chaitin.hpp"
    41 #include "opto/compile.hpp"
    42 #include "opto/connode.hpp"
    43 #include "opto/divnode.hpp"
    44 #include "opto/escape.hpp"
    45 #include "opto/idealGraphPrinter.hpp"
    46 #include "opto/loopnode.hpp"
    47 #include "opto/machnode.hpp"
    48 #include "opto/macro.hpp"
    49 #include "opto/matcher.hpp"
    50 #include "opto/mathexactnode.hpp"
    51 #include "opto/memnode.hpp"
    52 #include "opto/mulnode.hpp"
    53 #include "opto/node.hpp"
    54 #include "opto/opcodes.hpp"
    55 #include "opto/output.hpp"
    56 #include "opto/parse.hpp"
    57 #include "opto/phaseX.hpp"
    58 #include "opto/rootnode.hpp"
    59 #include "opto/runtime.hpp"
    60 #include "opto/stringopts.hpp"
    61 #include "opto/type.hpp"
    62 #include "opto/vectornode.hpp"
    63 #include "runtime/arguments.hpp"
    64 #include "runtime/signature.hpp"
    65 #include "runtime/stubRoutines.hpp"
    66 #include "runtime/timer.hpp"
    67 #include "trace/tracing.hpp"
    68 #include "utilities/copy.hpp"
    69 #ifdef TARGET_ARCH_MODEL_x86_32
    70 # include "adfiles/ad_x86_32.hpp"
    71 #endif
    72 #ifdef TARGET_ARCH_MODEL_x86_64
    73 # include "adfiles/ad_x86_64.hpp"
    74 #endif
    75 #ifdef TARGET_ARCH_MODEL_sparc
    76 # include "adfiles/ad_sparc.hpp"
    77 #endif
    78 #ifdef TARGET_ARCH_MODEL_zero
    79 # include "adfiles/ad_zero.hpp"
    80 #endif
    81 #ifdef TARGET_ARCH_MODEL_arm
    82 # include "adfiles/ad_arm.hpp"
    83 #endif
    84 #ifdef TARGET_ARCH_MODEL_ppc_32
    85 # include "adfiles/ad_ppc_32.hpp"
    86 #endif
    87 #ifdef TARGET_ARCH_MODEL_ppc_64
    88 # include "adfiles/ad_ppc_64.hpp"
    89 #endif
    92 // -------------------- Compile::mach_constant_base_node -----------------------
    93 // Constant table base node singleton.
    94 MachConstantBaseNode* Compile::mach_constant_base_node() {
    95   if (_mach_constant_base_node == NULL) {
    96     _mach_constant_base_node = new (C) MachConstantBaseNode();
    97     _mach_constant_base_node->add_req(C->root());
    98   }
    99   return _mach_constant_base_node;
   100 }
   103 /// Support for intrinsics.
   105 // Return the index at which m must be inserted (or already exists).
   106 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
   107 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual) {
   108 #ifdef ASSERT
   109   for (int i = 1; i < _intrinsics->length(); i++) {
   110     CallGenerator* cg1 = _intrinsics->at(i-1);
   111     CallGenerator* cg2 = _intrinsics->at(i);
   112     assert(cg1->method() != cg2->method()
   113            ? cg1->method()     < cg2->method()
   114            : cg1->is_virtual() < cg2->is_virtual(),
   115            "compiler intrinsics list must stay sorted");
   116   }
   117 #endif
   118   // Binary search sorted list, in decreasing intervals [lo, hi].
   119   int lo = 0, hi = _intrinsics->length()-1;
   120   while (lo <= hi) {
   121     int mid = (uint)(hi + lo) / 2;
   122     ciMethod* mid_m = _intrinsics->at(mid)->method();
   123     if (m < mid_m) {
   124       hi = mid-1;
   125     } else if (m > mid_m) {
   126       lo = mid+1;
   127     } else {
   128       // look at minor sort key
   129       bool mid_virt = _intrinsics->at(mid)->is_virtual();
   130       if (is_virtual < mid_virt) {
   131         hi = mid-1;
   132       } else if (is_virtual > mid_virt) {
   133         lo = mid+1;
   134       } else {
   135         return mid;  // exact match
   136       }
   137     }
   138   }
   139   return lo;  // inexact match
   140 }
   142 void Compile::register_intrinsic(CallGenerator* cg) {
   143   if (_intrinsics == NULL) {
   144     _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
   145   }
   146   // This code is stolen from ciObjectFactory::insert.
   147   // Really, GrowableArray should have methods for
   148   // insert_at, remove_at, and binary_search.
   149   int len = _intrinsics->length();
   150   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual());
   151   if (index == len) {
   152     _intrinsics->append(cg);
   153   } else {
   154 #ifdef ASSERT
   155     CallGenerator* oldcg = _intrinsics->at(index);
   156     assert(oldcg->method() != cg->method() || oldcg->is_virtual() != cg->is_virtual(), "don't register twice");
   157 #endif
   158     _intrinsics->append(_intrinsics->at(len-1));
   159     int pos;
   160     for (pos = len-2; pos >= index; pos--) {
   161       _intrinsics->at_put(pos+1,_intrinsics->at(pos));
   162     }
   163     _intrinsics->at_put(index, cg);
   164   }
   165   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
   166 }
   168 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
   169   assert(m->is_loaded(), "don't try this on unloaded methods");
   170   if (_intrinsics != NULL) {
   171     int index = intrinsic_insertion_index(m, is_virtual);
   172     if (index < _intrinsics->length()
   173         && _intrinsics->at(index)->method() == m
   174         && _intrinsics->at(index)->is_virtual() == is_virtual) {
   175       return _intrinsics->at(index);
   176     }
   177   }
   178   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
   179   if (m->intrinsic_id() != vmIntrinsics::_none &&
   180       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
   181     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
   182     if (cg != NULL) {
   183       // Save it for next time:
   184       register_intrinsic(cg);
   185       return cg;
   186     } else {
   187       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
   188     }
   189   }
   190   return NULL;
   191 }
   193 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
   194 // in library_call.cpp.
   197 #ifndef PRODUCT
   198 // statistics gathering...
   200 juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
   201 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
   203 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
   204   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
   205   int oflags = _intrinsic_hist_flags[id];
   206   assert(flags != 0, "what happened?");
   207   if (is_virtual) {
   208     flags |= _intrinsic_virtual;
   209   }
   210   bool changed = (flags != oflags);
   211   if ((flags & _intrinsic_worked) != 0) {
   212     juint count = (_intrinsic_hist_count[id] += 1);
   213     if (count == 1) {
   214       changed = true;           // first time
   215     }
   216     // increment the overall count also:
   217     _intrinsic_hist_count[vmIntrinsics::_none] += 1;
   218   }
   219   if (changed) {
   220     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
   221       // Something changed about the intrinsic's virtuality.
   222       if ((flags & _intrinsic_virtual) != 0) {
   223         // This is the first use of this intrinsic as a virtual call.
   224         if (oflags != 0) {
   225           // We already saw it as a non-virtual, so note both cases.
   226           flags |= _intrinsic_both;
   227         }
   228       } else if ((oflags & _intrinsic_both) == 0) {
   229         // This is the first use of this intrinsic as a non-virtual
   230         flags |= _intrinsic_both;
   231       }
   232     }
   233     _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
   234   }
   235   // update the overall flags also:
   236   _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
   237   return changed;
   238 }
   240 static char* format_flags(int flags, char* buf) {
   241   buf[0] = 0;
   242   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
   243   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
   244   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
   245   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
   246   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
   247   if (buf[0] == 0)  strcat(buf, ",");
   248   assert(buf[0] == ',', "must be");
   249   return &buf[1];
   250 }
   252 void Compile::print_intrinsic_statistics() {
   253   char flagsbuf[100];
   254   ttyLocker ttyl;
   255   if (xtty != NULL)  xtty->head("statistics type='intrinsic'");
   256   tty->print_cr("Compiler intrinsic usage:");
   257   juint total = _intrinsic_hist_count[vmIntrinsics::_none];
   258   if (total == 0)  total = 1;  // avoid div0 in case of no successes
   259   #define PRINT_STAT_LINE(name, c, f) \
   260     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
   261   for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
   262     vmIntrinsics::ID id = (vmIntrinsics::ID) index;
   263     int   flags = _intrinsic_hist_flags[id];
   264     juint count = _intrinsic_hist_count[id];
   265     if ((flags | count) != 0) {
   266       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
   267     }
   268   }
   269   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
   270   if (xtty != NULL)  xtty->tail("statistics");
   271 }
   273 void Compile::print_statistics() {
   274   { ttyLocker ttyl;
   275     if (xtty != NULL)  xtty->head("statistics type='opto'");
   276     Parse::print_statistics();
   277     PhaseCCP::print_statistics();
   278     PhaseRegAlloc::print_statistics();
   279     Scheduling::print_statistics();
   280     PhasePeephole::print_statistics();
   281     PhaseIdealLoop::print_statistics();
   282     if (xtty != NULL)  xtty->tail("statistics");
   283   }
   284   if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
   285     // put this under its own <statistics> element.
   286     print_intrinsic_statistics();
   287   }
   288 }
   289 #endif //PRODUCT
   291 // Support for bundling info
   292 Bundle* Compile::node_bundling(const Node *n) {
   293   assert(valid_bundle_info(n), "oob");
   294   return &_node_bundling_base[n->_idx];
   295 }
   297 bool Compile::valid_bundle_info(const Node *n) {
   298   return (_node_bundling_limit > n->_idx);
   299 }
   302 void Compile::gvn_replace_by(Node* n, Node* nn) {
   303   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
   304     Node* use = n->last_out(i);
   305     bool is_in_table = initial_gvn()->hash_delete(use);
   306     uint uses_found = 0;
   307     for (uint j = 0; j < use->len(); j++) {
   308       if (use->in(j) == n) {
   309         if (j < use->req())
   310           use->set_req(j, nn);
   311         else
   312           use->set_prec(j, nn);
   313         uses_found++;
   314       }
   315     }
   316     if (is_in_table) {
   317       // reinsert into table
   318       initial_gvn()->hash_find_insert(use);
   319     }
   320     record_for_igvn(use);
   321     i -= uses_found;    // we deleted 1 or more copies of this edge
   322   }
   323 }
   326 static inline bool not_a_node(const Node* n) {
   327   if (n == NULL)                   return true;
   328   if (((intptr_t)n & 1) != 0)      return true;  // uninitialized, etc.
   329   if (*(address*)n == badAddress)  return true;  // kill by Node::destruct
   330   return false;
   331 }
   333 // Identify all nodes that are reachable from below, useful.
   334 // Use breadth-first pass that records state in a Unique_Node_List,
   335 // recursive traversal is slower.
   336 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
   337   int estimated_worklist_size = unique();
   338   useful.map( estimated_worklist_size, NULL );  // preallocate space
   340   // Initialize worklist
   341   if (root() != NULL)     { useful.push(root()); }
   342   // If 'top' is cached, declare it useful to preserve cached node
   343   if( cached_top_node() ) { useful.push(cached_top_node()); }
   345   // Push all useful nodes onto the list, breadthfirst
   346   for( uint next = 0; next < useful.size(); ++next ) {
   347     assert( next < unique(), "Unique useful nodes < total nodes");
   348     Node *n  = useful.at(next);
   349     uint max = n->len();
   350     for( uint i = 0; i < max; ++i ) {
   351       Node *m = n->in(i);
   352       if (not_a_node(m))  continue;
   353       useful.push(m);
   354     }
   355   }
   356 }
   358 // Update dead_node_list with any missing dead nodes using useful
   359 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
   360 void Compile::update_dead_node_list(Unique_Node_List &useful) {
   361   uint max_idx = unique();
   362   VectorSet& useful_node_set = useful.member_set();
   364   for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
   365     // If node with index node_idx is not in useful set,
   366     // mark it as dead in dead node list.
   367     if (! useful_node_set.test(node_idx) ) {
   368       record_dead_node(node_idx);
   369     }
   370   }
   371 }
   373 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
   374   int shift = 0;
   375   for (int i = 0; i < inlines->length(); i++) {
   376     CallGenerator* cg = inlines->at(i);
   377     CallNode* call = cg->call_node();
   378     if (shift > 0) {
   379       inlines->at_put(i-shift, cg);
   380     }
   381     if (!useful.member(call)) {
   382       shift++;
   383     }
   384   }
   385   inlines->trunc_to(inlines->length()-shift);
   386 }
   388 // Disconnect all useless nodes by disconnecting those at the boundary.
   389 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
   390   uint next = 0;
   391   while (next < useful.size()) {
   392     Node *n = useful.at(next++);
   393     // Use raw traversal of out edges since this code removes out edges
   394     int max = n->outcnt();
   395     for (int j = 0; j < max; ++j) {
   396       Node* child = n->raw_out(j);
   397       if (! useful.member(child)) {
   398         assert(!child->is_top() || child != top(),
   399                "If top is cached in Compile object it is in useful list");
   400         // Only need to remove this out-edge to the useless node
   401         n->raw_del_out(j);
   402         --j;
   403         --max;
   404       }
   405     }
   406     if (n->outcnt() == 1 && n->has_special_unique_user()) {
   407       record_for_igvn(n->unique_out());
   408     }
   409   }
   410   // Remove useless macro and predicate opaq nodes
   411   for (int i = C->macro_count()-1; i >= 0; i--) {
   412     Node* n = C->macro_node(i);
   413     if (!useful.member(n)) {
   414       remove_macro_node(n);
   415     }
   416   }
   417   // Remove useless expensive node
   418   for (int i = C->expensive_count()-1; i >= 0; i--) {
   419     Node* n = C->expensive_node(i);
   420     if (!useful.member(n)) {
   421       remove_expensive_node(n);
   422     }
   423   }
   424   // clean up the late inline lists
   425   remove_useless_late_inlines(&_string_late_inlines, useful);
   426   remove_useless_late_inlines(&_boxing_late_inlines, useful);
   427   remove_useless_late_inlines(&_late_inlines, useful);
   428   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
   429 }
   431 //------------------------------frame_size_in_words-----------------------------
   432 // frame_slots in units of words
   433 int Compile::frame_size_in_words() const {
   434   // shift is 0 in LP32 and 1 in LP64
   435   const int shift = (LogBytesPerWord - LogBytesPerInt);
   436   int words = _frame_slots >> shift;
   437   assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
   438   return words;
   439 }
   441 // ============================================================================
   442 //------------------------------CompileWrapper---------------------------------
   443 class CompileWrapper : public StackObj {
   444   Compile *const _compile;
   445  public:
   446   CompileWrapper(Compile* compile);
   448   ~CompileWrapper();
   449 };
   451 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
   452   // the Compile* pointer is stored in the current ciEnv:
   453   ciEnv* env = compile->env();
   454   assert(env == ciEnv::current(), "must already be a ciEnv active");
   455   assert(env->compiler_data() == NULL, "compile already active?");
   456   env->set_compiler_data(compile);
   457   assert(compile == Compile::current(), "sanity");
   459   compile->set_type_dict(NULL);
   460   compile->set_type_hwm(NULL);
   461   compile->set_type_last_size(0);
   462   compile->set_last_tf(NULL, NULL);
   463   compile->set_indexSet_arena(NULL);
   464   compile->set_indexSet_free_block_list(NULL);
   465   compile->init_type_arena();
   466   Type::Initialize(compile);
   467   _compile->set_scratch_buffer_blob(NULL);
   468   _compile->begin_method();
   469 }
   470 CompileWrapper::~CompileWrapper() {
   471   _compile->end_method();
   472   if (_compile->scratch_buffer_blob() != NULL)
   473     BufferBlob::free(_compile->scratch_buffer_blob());
   474   _compile->env()->set_compiler_data(NULL);
   475 }
   478 //----------------------------print_compile_messages---------------------------
   479 void Compile::print_compile_messages() {
   480 #ifndef PRODUCT
   481   // Check if recompiling
   482   if (_subsume_loads == false && PrintOpto) {
   483     // Recompiling without allowing machine instructions to subsume loads
   484     tty->print_cr("*********************************************************");
   485     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
   486     tty->print_cr("*********************************************************");
   487   }
   488   if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
   489     // Recompiling without escape analysis
   490     tty->print_cr("*********************************************************");
   491     tty->print_cr("** Bailout: Recompile without escape analysis          **");
   492     tty->print_cr("*********************************************************");
   493   }
   494   if (_eliminate_boxing != EliminateAutoBox && PrintOpto) {
   495     // Recompiling without boxing elimination
   496     tty->print_cr("*********************************************************");
   497     tty->print_cr("** Bailout: Recompile without boxing elimination       **");
   498     tty->print_cr("*********************************************************");
   499   }
   500   if (env()->break_at_compile()) {
   501     // Open the debugger when compiling this method.
   502     tty->print("### Breaking when compiling: ");
   503     method()->print_short_name();
   504     tty->cr();
   505     BREAKPOINT;
   506   }
   508   if( PrintOpto ) {
   509     if (is_osr_compilation()) {
   510       tty->print("[OSR]%3d", _compile_id);
   511     } else {
   512       tty->print("%3d", _compile_id);
   513     }
   514   }
   515 #endif
   516 }
   519 //-----------------------init_scratch_buffer_blob------------------------------
   520 // Construct a temporary BufferBlob and cache it for this compile.
   521 void Compile::init_scratch_buffer_blob(int const_size) {
   522   // If there is already a scratch buffer blob allocated and the
   523   // constant section is big enough, use it.  Otherwise free the
   524   // current and allocate a new one.
   525   BufferBlob* blob = scratch_buffer_blob();
   526   if ((blob != NULL) && (const_size <= _scratch_const_size)) {
   527     // Use the current blob.
   528   } else {
   529     if (blob != NULL) {
   530       BufferBlob::free(blob);
   531     }
   533     ResourceMark rm;
   534     _scratch_const_size = const_size;
   535     int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
   536     blob = BufferBlob::create("Compile::scratch_buffer", size);
   537     // Record the buffer blob for next time.
   538     set_scratch_buffer_blob(blob);
   539     // Have we run out of code space?
   540     if (scratch_buffer_blob() == NULL) {
   541       // Let CompilerBroker disable further compilations.
   542       record_failure("Not enough space for scratch buffer in CodeCache");
   543       return;
   544     }
   545   }
   547   // Initialize the relocation buffers
   548   relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
   549   set_scratch_locs_memory(locs_buf);
   550 }
   553 //-----------------------scratch_emit_size-------------------------------------
   554 // Helper function that computes size by emitting code
   555 uint Compile::scratch_emit_size(const Node* n) {
   556   // Start scratch_emit_size section.
   557   set_in_scratch_emit_size(true);
   559   // Emit into a trash buffer and count bytes emitted.
   560   // This is a pretty expensive way to compute a size,
   561   // but it works well enough if seldom used.
   562   // All common fixed-size instructions are given a size
   563   // method by the AD file.
   564   // Note that the scratch buffer blob and locs memory are
   565   // allocated at the beginning of the compile task, and
   566   // may be shared by several calls to scratch_emit_size.
   567   // The allocation of the scratch buffer blob is particularly
   568   // expensive, since it has to grab the code cache lock.
   569   BufferBlob* blob = this->scratch_buffer_blob();
   570   assert(blob != NULL, "Initialize BufferBlob at start");
   571   assert(blob->size() > MAX_inst_size, "sanity");
   572   relocInfo* locs_buf = scratch_locs_memory();
   573   address blob_begin = blob->content_begin();
   574   address blob_end   = (address)locs_buf;
   575   assert(blob->content_contains(blob_end), "sanity");
   576   CodeBuffer buf(blob_begin, blob_end - blob_begin);
   577   buf.initialize_consts_size(_scratch_const_size);
   578   buf.initialize_stubs_size(MAX_stubs_size);
   579   assert(locs_buf != NULL, "sanity");
   580   int lsize = MAX_locs_size / 3;
   581   buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
   582   buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
   583   buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
   585   // Do the emission.
   587   Label fakeL; // Fake label for branch instructions.
   588   Label*   saveL = NULL;
   589   uint save_bnum = 0;
   590   bool is_branch = n->is_MachBranch();
   591   if (is_branch) {
   592     MacroAssembler masm(&buf);
   593     masm.bind(fakeL);
   594     n->as_MachBranch()->save_label(&saveL, &save_bnum);
   595     n->as_MachBranch()->label_set(&fakeL, 0);
   596   }
   597   n->emit(buf, this->regalloc());
   598   if (is_branch) // Restore label.
   599     n->as_MachBranch()->label_set(saveL, save_bnum);
   601   // End scratch_emit_size section.
   602   set_in_scratch_emit_size(false);
   604   return buf.insts_size();
   605 }
   608 // ============================================================================
   609 //------------------------------Compile standard-------------------------------
   610 debug_only( int Compile::_debug_idx = 100000; )
   612 // Compile a method.  entry_bci is -1 for normal compilations and indicates
   613 // the continuation bci for on stack replacement.
   616 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci,
   617                   bool subsume_loads, bool do_escape_analysis, bool eliminate_boxing )
   618                 : Phase(Compiler),
   619                   _env(ci_env),
   620                   _log(ci_env->log()),
   621                   _compile_id(ci_env->compile_id()),
   622                   _save_argument_registers(false),
   623                   _stub_name(NULL),
   624                   _stub_function(NULL),
   625                   _stub_entry_point(NULL),
   626                   _method(target),
   627                   _entry_bci(osr_bci),
   628                   _initial_gvn(NULL),
   629                   _for_igvn(NULL),
   630                   _warm_calls(NULL),
   631                   _subsume_loads(subsume_loads),
   632                   _do_escape_analysis(do_escape_analysis),
   633                   _eliminate_boxing(eliminate_boxing),
   634                   _failure_reason(NULL),
   635                   _code_buffer("Compile::Fill_buffer"),
   636                   _orig_pc_slot(0),
   637                   _orig_pc_slot_offset_in_bytes(0),
   638                   _has_method_handle_invokes(false),
   639                   _mach_constant_base_node(NULL),
   640                   _node_bundling_limit(0),
   641                   _node_bundling_base(NULL),
   642                   _java_calls(0),
   643                   _inner_loops(0),
   644                   _scratch_const_size(-1),
   645                   _in_scratch_emit_size(false),
   646                   _dead_node_list(comp_arena()),
   647                   _dead_node_count(0),
   648 #ifndef PRODUCT
   649                   _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
   650                   _printer(IdealGraphPrinter::printer()),
   651 #endif
   652                   _congraph(NULL),
   653                   _late_inlines(comp_arena(), 2, 0, NULL),
   654                   _string_late_inlines(comp_arena(), 2, 0, NULL),
   655                   _boxing_late_inlines(comp_arena(), 2, 0, NULL),
   656                   _late_inlines_pos(0),
   657                   _number_of_mh_late_inlines(0),
   658                   _inlining_progress(false),
   659                   _inlining_incrementally(false),
   660                   _print_inlining_list(NULL),
   661                   _print_inlining_idx(0),
   662                   _preserve_jvm_state(0) {
   663   C = this;
   665   CompileWrapper cw(this);
   666 #ifndef PRODUCT
   667   if (TimeCompiler2) {
   668     tty->print(" ");
   669     target->holder()->name()->print();
   670     tty->print(".");
   671     target->print_short_name();
   672     tty->print("  ");
   673   }
   674   TraceTime t1("Total compilation time", &_t_totalCompilation, TimeCompiler, TimeCompiler2);
   675   TraceTime t2(NULL, &_t_methodCompilation, TimeCompiler, false);
   676   bool print_opto_assembly = PrintOptoAssembly || _method->has_option("PrintOptoAssembly");
   677   if (!print_opto_assembly) {
   678     bool print_assembly = (PrintAssembly || _method->should_print_assembly());
   679     if (print_assembly && !Disassembler::can_decode()) {
   680       tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
   681       print_opto_assembly = true;
   682     }
   683   }
   684   set_print_assembly(print_opto_assembly);
   685   set_parsed_irreducible_loop(false);
   686 #endif
   687   set_print_inlining(PrintInlining || method()->has_option("PrintInlining") NOT_PRODUCT( || PrintOptoInlining));
   688   set_print_intrinsics(PrintIntrinsics || method()->has_option("PrintIntrinsics"));
   690   if (ProfileTraps) {
   691     // Make sure the method being compiled gets its own MDO,
   692     // so we can at least track the decompile_count().
   693     method()->ensure_method_data();
   694   }
   696   Init(::AliasLevel);
   699   print_compile_messages();
   701   if (UseOldInlining || PrintCompilation NOT_PRODUCT( || PrintOpto) )
   702     _ilt = InlineTree::build_inline_tree_root();
   703   else
   704     _ilt = NULL;
   706   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
   707   assert(num_alias_types() >= AliasIdxRaw, "");
   709 #define MINIMUM_NODE_HASH  1023
   710   // Node list that Iterative GVN will start with
   711   Unique_Node_List for_igvn(comp_arena());
   712   set_for_igvn(&for_igvn);
   714   // GVN that will be run immediately on new nodes
   715   uint estimated_size = method()->code_size()*4+64;
   716   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
   717   PhaseGVN gvn(node_arena(), estimated_size);
   718   set_initial_gvn(&gvn);
   720   if (print_inlining() || print_intrinsics()) {
   721     _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
   722   }
   723   { // Scope for timing the parser
   724     TracePhase t3("parse", &_t_parser, true);
   726     // Put top into the hash table ASAP.
   727     initial_gvn()->transform_no_reclaim(top());
   729     // Set up tf(), start(), and find a CallGenerator.
   730     CallGenerator* cg = NULL;
   731     if (is_osr_compilation()) {
   732       const TypeTuple *domain = StartOSRNode::osr_domain();
   733       const TypeTuple *range = TypeTuple::make_range(method()->signature());
   734       init_tf(TypeFunc::make(domain, range));
   735       StartNode* s = new (this) StartOSRNode(root(), domain);
   736       initial_gvn()->set_type_bottom(s);
   737       init_start(s);
   738       cg = CallGenerator::for_osr(method(), entry_bci());
   739     } else {
   740       // Normal case.
   741       init_tf(TypeFunc::make(method()));
   742       StartNode* s = new (this) StartNode(root(), tf()->domain());
   743       initial_gvn()->set_type_bottom(s);
   744       init_start(s);
   745       if (method()->intrinsic_id() == vmIntrinsics::_Reference_get && UseG1GC) {
   746         // With java.lang.ref.reference.get() we must go through the
   747         // intrinsic when G1 is enabled - even when get() is the root
   748         // method of the compile - so that, if necessary, the value in
   749         // the referent field of the reference object gets recorded by
   750         // the pre-barrier code.
   751         // Specifically, if G1 is enabled, the value in the referent
   752         // field is recorded by the G1 SATB pre barrier. This will
   753         // result in the referent being marked live and the reference
   754         // object removed from the list of discovered references during
   755         // reference processing.
   756         cg = find_intrinsic(method(), false);
   757       }
   758       if (cg == NULL) {
   759         float past_uses = method()->interpreter_invocation_count();
   760         float expected_uses = past_uses;
   761         cg = CallGenerator::for_inline(method(), expected_uses);
   762       }
   763     }
   764     if (failing())  return;
   765     if (cg == NULL) {
   766       record_method_not_compilable_all_tiers("cannot parse method");
   767       return;
   768     }
   769     JVMState* jvms = build_start_state(start(), tf());
   770     if ((jvms = cg->generate(jvms, NULL)) == NULL) {
   771       record_method_not_compilable("method parse failed");
   772       return;
   773     }
   774     GraphKit kit(jvms);
   776     if (!kit.stopped()) {
   777       // Accept return values, and transfer control we know not where.
   778       // This is done by a special, unique ReturnNode bound to root.
   779       return_values(kit.jvms());
   780     }
   782     if (kit.has_exceptions()) {
   783       // Any exceptions that escape from this call must be rethrown
   784       // to whatever caller is dynamically above us on the stack.
   785       // This is done by a special, unique RethrowNode bound to root.
   786       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
   787     }
   789     assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
   791     if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
   792       inline_string_calls(true);
   793     }
   795     if (failing())  return;
   797     print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
   799     // Remove clutter produced by parsing.
   800     if (!failing()) {
   801       ResourceMark rm;
   802       PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
   803     }
   804   }
   806   // Note:  Large methods are capped off in do_one_bytecode().
   807   if (failing())  return;
   809   // After parsing, node notes are no longer automagic.
   810   // They must be propagated by register_new_node_with_optimizer(),
   811   // clone(), or the like.
   812   set_default_node_notes(NULL);
   814   for (;;) {
   815     int successes = Inline_Warm();
   816     if (failing())  return;
   817     if (successes == 0)  break;
   818   }
   820   // Drain the list.
   821   Finish_Warm();
   822 #ifndef PRODUCT
   823   if (_printer) {
   824     _printer->print_inlining(this);
   825   }
   826 #endif
   828   if (failing())  return;
   829   NOT_PRODUCT( verify_graph_edges(); )
   831   // Now optimize
   832   Optimize();
   833   if (failing())  return;
   834   NOT_PRODUCT( verify_graph_edges(); )
   836 #ifndef PRODUCT
   837   if (PrintIdeal) {
   838     ttyLocker ttyl;  // keep the following output all in one block
   839     // This output goes directly to the tty, not the compiler log.
   840     // To enable tools to match it up with the compilation activity,
   841     // be sure to tag this tty output with the compile ID.
   842     if (xtty != NULL) {
   843       xtty->head("ideal compile_id='%d'%s", compile_id(),
   844                  is_osr_compilation()    ? " compile_kind='osr'" :
   845                  "");
   846     }
   847     root()->dump(9999);
   848     if (xtty != NULL) {
   849       xtty->tail("ideal");
   850     }
   851   }
   852 #endif
   854   NOT_PRODUCT( verify_barriers(); )
   855   // Now that we know the size of all the monitors we can add a fixed slot
   856   // for the original deopt pc.
   858   _orig_pc_slot =  fixed_slots();
   859   int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
   860   set_fixed_slots(next_slot);
   862   // Now generate code
   863   Code_Gen();
   864   if (failing())  return;
   866   // Check if we want to skip execution of all compiled code.
   867   {
   868 #ifndef PRODUCT
   869     if (OptoNoExecute) {
   870       record_method_not_compilable("+OptoNoExecute");  // Flag as failed
   871       return;
   872     }
   873     TracePhase t2("install_code", &_t_registerMethod, TimeCompiler);
   874 #endif
   876     if (is_osr_compilation()) {
   877       _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
   878       _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
   879     } else {
   880       _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
   881       _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
   882     }
   884     env()->register_method(_method, _entry_bci,
   885                            &_code_offsets,
   886                            _orig_pc_slot_offset_in_bytes,
   887                            code_buffer(),
   888                            frame_size_in_words(), _oop_map_set,
   889                            &_handler_table, &_inc_table,
   890                            compiler,
   891                            env()->comp_level(),
   892                            has_unsafe_access(),
   893                            SharedRuntime::is_wide_vector(max_vector_size())
   894                            );
   896     if (log() != NULL) // Print code cache state into compiler log
   897       log()->code_cache_state();
   898   }
   899 }
   901 //------------------------------Compile----------------------------------------
   902 // Compile a runtime stub
   903 Compile::Compile( ciEnv* ci_env,
   904                   TypeFunc_generator generator,
   905                   address stub_function,
   906                   const char *stub_name,
   907                   int is_fancy_jump,
   908                   bool pass_tls,
   909                   bool save_arg_registers,
   910                   bool return_pc )
   911   : Phase(Compiler),
   912     _env(ci_env),
   913     _log(ci_env->log()),
   914     _compile_id(0),
   915     _save_argument_registers(save_arg_registers),
   916     _method(NULL),
   917     _stub_name(stub_name),
   918     _stub_function(stub_function),
   919     _stub_entry_point(NULL),
   920     _entry_bci(InvocationEntryBci),
   921     _initial_gvn(NULL),
   922     _for_igvn(NULL),
   923     _warm_calls(NULL),
   924     _orig_pc_slot(0),
   925     _orig_pc_slot_offset_in_bytes(0),
   926     _subsume_loads(true),
   927     _do_escape_analysis(false),
   928     _eliminate_boxing(false),
   929     _failure_reason(NULL),
   930     _code_buffer("Compile::Fill_buffer"),
   931     _has_method_handle_invokes(false),
   932     _mach_constant_base_node(NULL),
   933     _node_bundling_limit(0),
   934     _node_bundling_base(NULL),
   935     _java_calls(0),
   936     _inner_loops(0),
   937 #ifndef PRODUCT
   938     _trace_opto_output(TraceOptoOutput),
   939     _printer(NULL),
   940 #endif
   941     _dead_node_list(comp_arena()),
   942     _dead_node_count(0),
   943     _congraph(NULL),
   944     _number_of_mh_late_inlines(0),
   945     _inlining_progress(false),
   946     _inlining_incrementally(false),
   947     _print_inlining_list(NULL),
   948     _print_inlining_idx(0),
   949     _preserve_jvm_state(0) {
   950   C = this;
   952 #ifndef PRODUCT
   953   TraceTime t1(NULL, &_t_totalCompilation, TimeCompiler, false);
   954   TraceTime t2(NULL, &_t_stubCompilation, TimeCompiler, false);
   955   set_print_assembly(PrintFrameConverterAssembly);
   956   set_parsed_irreducible_loop(false);
   957 #endif
   958   CompileWrapper cw(this);
   959   Init(/*AliasLevel=*/ 0);
   960   init_tf((*generator)());
   962   {
   963     // The following is a dummy for the sake of GraphKit::gen_stub
   964     Unique_Node_List for_igvn(comp_arena());
   965     set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
   966     PhaseGVN gvn(Thread::current()->resource_area(),255);
   967     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
   968     gvn.transform_no_reclaim(top());
   970     GraphKit kit;
   971     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
   972   }
   974   NOT_PRODUCT( verify_graph_edges(); )
   975   Code_Gen();
   976   if (failing())  return;
   979   // Entry point will be accessed using compile->stub_entry_point();
   980   if (code_buffer() == NULL) {
   981     Matcher::soft_match_failure();
   982   } else {
   983     if (PrintAssembly && (WizardMode || Verbose))
   984       tty->print_cr("### Stub::%s", stub_name);
   986     if (!failing()) {
   987       assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
   989       // Make the NMethod
   990       // For now we mark the frame as never safe for profile stackwalking
   991       RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
   992                                                       code_buffer(),
   993                                                       CodeOffsets::frame_never_safe,
   994                                                       // _code_offsets.value(CodeOffsets::Frame_Complete),
   995                                                       frame_size_in_words(),
   996                                                       _oop_map_set,
   997                                                       save_arg_registers);
   998       assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
  1000       _stub_entry_point = rs->entry_point();
  1005 //------------------------------Init-------------------------------------------
  1006 // Prepare for a single compilation
  1007 void Compile::Init(int aliaslevel) {
  1008   _unique  = 0;
  1009   _regalloc = NULL;
  1011   _tf      = NULL;  // filled in later
  1012   _top     = NULL;  // cached later
  1013   _matcher = NULL;  // filled in later
  1014   _cfg     = NULL;  // filled in later
  1016   set_24_bit_selection_and_mode(Use24BitFP, false);
  1018   _node_note_array = NULL;
  1019   _default_node_notes = NULL;
  1021   _immutable_memory = NULL; // filled in at first inquiry
  1023   // Globally visible Nodes
  1024   // First set TOP to NULL to give safe behavior during creation of RootNode
  1025   set_cached_top_node(NULL);
  1026   set_root(new (this) RootNode());
  1027   // Now that you have a Root to point to, create the real TOP
  1028   set_cached_top_node( new (this) ConNode(Type::TOP) );
  1029   set_recent_alloc(NULL, NULL);
  1031   // Create Debug Information Recorder to record scopes, oopmaps, etc.
  1032   env()->set_oop_recorder(new OopRecorder(env()->arena()));
  1033   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
  1034   env()->set_dependencies(new Dependencies(env()));
  1036   _fixed_slots = 0;
  1037   set_has_split_ifs(false);
  1038   set_has_loops(has_method() && method()->has_loops()); // first approximation
  1039   set_has_stringbuilder(false);
  1040   set_has_boxed_value(false);
  1041   _trap_can_recompile = false;  // no traps emitted yet
  1042   _major_progress = true; // start out assuming good things will happen
  1043   set_has_unsafe_access(false);
  1044   set_max_vector_size(0);
  1045   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
  1046   set_decompile_count(0);
  1048   set_do_freq_based_layout(BlockLayoutByFrequency || method_has_option("BlockLayoutByFrequency"));
  1049   set_num_loop_opts(LoopOptsCount);
  1050   set_do_inlining(Inline);
  1051   set_max_inline_size(MaxInlineSize);
  1052   set_freq_inline_size(FreqInlineSize);
  1053   set_do_scheduling(OptoScheduling);
  1054   set_do_count_invocations(false);
  1055   set_do_method_data_update(false);
  1057   if (debug_info()->recording_non_safepoints()) {
  1058     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
  1059                         (comp_arena(), 8, 0, NULL));
  1060     set_default_node_notes(Node_Notes::make(this));
  1063   // // -- Initialize types before each compile --
  1064   // // Update cached type information
  1065   // if( _method && _method->constants() )
  1066   //   Type::update_loaded_types(_method, _method->constants());
  1068   // Init alias_type map.
  1069   if (!_do_escape_analysis && aliaslevel == 3)
  1070     aliaslevel = 2;  // No unique types without escape analysis
  1071   _AliasLevel = aliaslevel;
  1072   const int grow_ats = 16;
  1073   _max_alias_types = grow_ats;
  1074   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
  1075   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
  1076   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
  1078     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
  1080   // Initialize the first few types.
  1081   _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
  1082   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
  1083   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
  1084   _num_alias_types = AliasIdxRaw+1;
  1085   // Zero out the alias type cache.
  1086   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
  1087   // A NULL adr_type hits in the cache right away.  Preload the right answer.
  1088   probe_alias_cache(NULL)->_index = AliasIdxTop;
  1090   _intrinsics = NULL;
  1091   _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1092   _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1093   _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1094   register_library_intrinsics();
  1097 //---------------------------init_start----------------------------------------
  1098 // Install the StartNode on this compile object.
  1099 void Compile::init_start(StartNode* s) {
  1100   if (failing())
  1101     return; // already failing
  1102   assert(s == start(), "");
  1105 StartNode* Compile::start() const {
  1106   assert(!failing(), "");
  1107   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
  1108     Node* start = root()->fast_out(i);
  1109     if( start->is_Start() )
  1110       return start->as_Start();
  1112   ShouldNotReachHere();
  1113   return NULL;
  1116 //-------------------------------immutable_memory-------------------------------------
  1117 // Access immutable memory
  1118 Node* Compile::immutable_memory() {
  1119   if (_immutable_memory != NULL) {
  1120     return _immutable_memory;
  1122   StartNode* s = start();
  1123   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
  1124     Node *p = s->fast_out(i);
  1125     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
  1126       _immutable_memory = p;
  1127       return _immutable_memory;
  1130   ShouldNotReachHere();
  1131   return NULL;
  1134 //----------------------set_cached_top_node------------------------------------
  1135 // Install the cached top node, and make sure Node::is_top works correctly.
  1136 void Compile::set_cached_top_node(Node* tn) {
  1137   if (tn != NULL)  verify_top(tn);
  1138   Node* old_top = _top;
  1139   _top = tn;
  1140   // Calling Node::setup_is_top allows the nodes the chance to adjust
  1141   // their _out arrays.
  1142   if (_top != NULL)     _top->setup_is_top();
  1143   if (old_top != NULL)  old_top->setup_is_top();
  1144   assert(_top == NULL || top()->is_top(), "");
  1147 #ifdef ASSERT
  1148 uint Compile::count_live_nodes_by_graph_walk() {
  1149   Unique_Node_List useful(comp_arena());
  1150   // Get useful node list by walking the graph.
  1151   identify_useful_nodes(useful);
  1152   return useful.size();
  1155 void Compile::print_missing_nodes() {
  1157   // Return if CompileLog is NULL and PrintIdealNodeCount is false.
  1158   if ((_log == NULL) && (! PrintIdealNodeCount)) {
  1159     return;
  1162   // This is an expensive function. It is executed only when the user
  1163   // specifies VerifyIdealNodeCount option or otherwise knows the
  1164   // additional work that needs to be done to identify reachable nodes
  1165   // by walking the flow graph and find the missing ones using
  1166   // _dead_node_list.
  1168   Unique_Node_List useful(comp_arena());
  1169   // Get useful node list by walking the graph.
  1170   identify_useful_nodes(useful);
  1172   uint l_nodes = C->live_nodes();
  1173   uint l_nodes_by_walk = useful.size();
  1175   if (l_nodes != l_nodes_by_walk) {
  1176     if (_log != NULL) {
  1177       _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
  1178       _log->stamp();
  1179       _log->end_head();
  1181     VectorSet& useful_member_set = useful.member_set();
  1182     int last_idx = l_nodes_by_walk;
  1183     for (int i = 0; i < last_idx; i++) {
  1184       if (useful_member_set.test(i)) {
  1185         if (_dead_node_list.test(i)) {
  1186           if (_log != NULL) {
  1187             _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
  1189           if (PrintIdealNodeCount) {
  1190             // Print the log message to tty
  1191               tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
  1192               useful.at(i)->dump();
  1196       else if (! _dead_node_list.test(i)) {
  1197         if (_log != NULL) {
  1198           _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
  1200         if (PrintIdealNodeCount) {
  1201           // Print the log message to tty
  1202           tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
  1206     if (_log != NULL) {
  1207       _log->tail("mismatched_nodes");
  1211 #endif
  1213 #ifndef PRODUCT
  1214 void Compile::verify_top(Node* tn) const {
  1215   if (tn != NULL) {
  1216     assert(tn->is_Con(), "top node must be a constant");
  1217     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
  1218     assert(tn->in(0) != NULL, "must have live top node");
  1221 #endif
  1224 ///-------------------Managing Per-Node Debug & Profile Info-------------------
  1226 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
  1227   guarantee(arr != NULL, "");
  1228   int num_blocks = arr->length();
  1229   if (grow_by < num_blocks)  grow_by = num_blocks;
  1230   int num_notes = grow_by * _node_notes_block_size;
  1231   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
  1232   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
  1233   while (num_notes > 0) {
  1234     arr->append(notes);
  1235     notes     += _node_notes_block_size;
  1236     num_notes -= _node_notes_block_size;
  1238   assert(num_notes == 0, "exact multiple, please");
  1241 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
  1242   if (source == NULL || dest == NULL)  return false;
  1244   if (dest->is_Con())
  1245     return false;               // Do not push debug info onto constants.
  1247 #ifdef ASSERT
  1248   // Leave a bread crumb trail pointing to the original node:
  1249   if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
  1250     dest->set_debug_orig(source);
  1252 #endif
  1254   if (node_note_array() == NULL)
  1255     return false;               // Not collecting any notes now.
  1257   // This is a copy onto a pre-existing node, which may already have notes.
  1258   // If both nodes have notes, do not overwrite any pre-existing notes.
  1259   Node_Notes* source_notes = node_notes_at(source->_idx);
  1260   if (source_notes == NULL || source_notes->is_clear())  return false;
  1261   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
  1262   if (dest_notes == NULL || dest_notes->is_clear()) {
  1263     return set_node_notes_at(dest->_idx, source_notes);
  1266   Node_Notes merged_notes = (*source_notes);
  1267   // The order of operations here ensures that dest notes will win...
  1268   merged_notes.update_from(dest_notes);
  1269   return set_node_notes_at(dest->_idx, &merged_notes);
  1273 //--------------------------allow_range_check_smearing-------------------------
  1274 // Gating condition for coalescing similar range checks.
  1275 // Sometimes we try 'speculatively' replacing a series of a range checks by a
  1276 // single covering check that is at least as strong as any of them.
  1277 // If the optimization succeeds, the simplified (strengthened) range check
  1278 // will always succeed.  If it fails, we will deopt, and then give up
  1279 // on the optimization.
  1280 bool Compile::allow_range_check_smearing() const {
  1281   // If this method has already thrown a range-check,
  1282   // assume it was because we already tried range smearing
  1283   // and it failed.
  1284   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
  1285   return !already_trapped;
  1289 //------------------------------flatten_alias_type-----------------------------
  1290 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
  1291   int offset = tj->offset();
  1292   TypePtr::PTR ptr = tj->ptr();
  1294   // Known instance (scalarizable allocation) alias only with itself.
  1295   bool is_known_inst = tj->isa_oopptr() != NULL &&
  1296                        tj->is_oopptr()->is_known_instance();
  1298   // Process weird unsafe references.
  1299   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
  1300     assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
  1301     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
  1302     tj = TypeOopPtr::BOTTOM;
  1303     ptr = tj->ptr();
  1304     offset = tj->offset();
  1307   // Array pointers need some flattening
  1308   const TypeAryPtr *ta = tj->isa_aryptr();
  1309   if (ta && ta->is_stable()) {
  1310     // Erase stability property for alias analysis.
  1311     tj = ta = ta->cast_to_stable(false);
  1313   if( ta && is_known_inst ) {
  1314     if ( offset != Type::OffsetBot &&
  1315          offset > arrayOopDesc::length_offset_in_bytes() ) {
  1316       offset = Type::OffsetBot; // Flatten constant access into array body only
  1317       tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
  1319   } else if( ta && _AliasLevel >= 2 ) {
  1320     // For arrays indexed by constant indices, we flatten the alias
  1321     // space to include all of the array body.  Only the header, klass
  1322     // and array length can be accessed un-aliased.
  1323     if( offset != Type::OffsetBot ) {
  1324       if( ta->const_oop() ) { // MethodData* or Method*
  1325         offset = Type::OffsetBot;   // Flatten constant access into array body
  1326         tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
  1327       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
  1328         // range is OK as-is.
  1329         tj = ta = TypeAryPtr::RANGE;
  1330       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
  1331         tj = TypeInstPtr::KLASS; // all klass loads look alike
  1332         ta = TypeAryPtr::RANGE; // generic ignored junk
  1333         ptr = TypePtr::BotPTR;
  1334       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
  1335         tj = TypeInstPtr::MARK;
  1336         ta = TypeAryPtr::RANGE; // generic ignored junk
  1337         ptr = TypePtr::BotPTR;
  1338       } else {                  // Random constant offset into array body
  1339         offset = Type::OffsetBot;   // Flatten constant access into array body
  1340         tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
  1343     // Arrays of fixed size alias with arrays of unknown size.
  1344     if (ta->size() != TypeInt::POS) {
  1345       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
  1346       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
  1348     // Arrays of known objects become arrays of unknown objects.
  1349     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
  1350       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
  1351       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
  1353     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
  1354       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
  1355       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
  1357     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
  1358     // cannot be distinguished by bytecode alone.
  1359     if (ta->elem() == TypeInt::BOOL) {
  1360       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
  1361       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
  1362       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
  1364     // During the 2nd round of IterGVN, NotNull castings are removed.
  1365     // Make sure the Bottom and NotNull variants alias the same.
  1366     // Also, make sure exact and non-exact variants alias the same.
  1367     if (ptr == TypePtr::NotNull || ta->klass_is_exact() || ta->speculative() != NULL) {
  1368       tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
  1372   // Oop pointers need some flattening
  1373   const TypeInstPtr *to = tj->isa_instptr();
  1374   if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
  1375     ciInstanceKlass *k = to->klass()->as_instance_klass();
  1376     if( ptr == TypePtr::Constant ) {
  1377       if (to->klass() != ciEnv::current()->Class_klass() ||
  1378           offset < k->size_helper() * wordSize) {
  1379         // No constant oop pointers (such as Strings); they alias with
  1380         // unknown strings.
  1381         assert(!is_known_inst, "not scalarizable allocation");
  1382         tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
  1384     } else if( is_known_inst ) {
  1385       tj = to; // Keep NotNull and klass_is_exact for instance type
  1386     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
  1387       // During the 2nd round of IterGVN, NotNull castings are removed.
  1388       // Make sure the Bottom and NotNull variants alias the same.
  1389       // Also, make sure exact and non-exact variants alias the same.
  1390       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
  1392     if (to->speculative() != NULL) {
  1393       tj = to = TypeInstPtr::make(to->ptr(),to->klass(),to->klass_is_exact(),to->const_oop(),to->offset(), to->instance_id());
  1395     // Canonicalize the holder of this field
  1396     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
  1397       // First handle header references such as a LoadKlassNode, even if the
  1398       // object's klass is unloaded at compile time (4965979).
  1399       if (!is_known_inst) { // Do it only for non-instance types
  1400         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
  1402     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
  1403       // Static fields are in the space above the normal instance
  1404       // fields in the java.lang.Class instance.
  1405       if (to->klass() != ciEnv::current()->Class_klass()) {
  1406         to = NULL;
  1407         tj = TypeOopPtr::BOTTOM;
  1408         offset = tj->offset();
  1410     } else {
  1411       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
  1412       if (!k->equals(canonical_holder) || tj->offset() != offset) {
  1413         if( is_known_inst ) {
  1414           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
  1415         } else {
  1416           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
  1422   // Klass pointers to object array klasses need some flattening
  1423   const TypeKlassPtr *tk = tj->isa_klassptr();
  1424   if( tk ) {
  1425     // If we are referencing a field within a Klass, we need
  1426     // to assume the worst case of an Object.  Both exact and
  1427     // inexact types must flatten to the same alias class so
  1428     // use NotNull as the PTR.
  1429     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
  1431       tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
  1432                                    TypeKlassPtr::OBJECT->klass(),
  1433                                    offset);
  1436     ciKlass* klass = tk->klass();
  1437     if( klass->is_obj_array_klass() ) {
  1438       ciKlass* k = TypeAryPtr::OOPS->klass();
  1439       if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
  1440         k = TypeInstPtr::BOTTOM->klass();
  1441       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
  1444     // Check for precise loads from the primary supertype array and force them
  1445     // to the supertype cache alias index.  Check for generic array loads from
  1446     // the primary supertype array and also force them to the supertype cache
  1447     // alias index.  Since the same load can reach both, we need to merge
  1448     // these 2 disparate memories into the same alias class.  Since the
  1449     // primary supertype array is read-only, there's no chance of confusion
  1450     // where we bypass an array load and an array store.
  1451     int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
  1452     if (offset == Type::OffsetBot ||
  1453         (offset >= primary_supers_offset &&
  1454          offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
  1455         offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
  1456       offset = in_bytes(Klass::secondary_super_cache_offset());
  1457       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
  1461   // Flatten all Raw pointers together.
  1462   if (tj->base() == Type::RawPtr)
  1463     tj = TypeRawPtr::BOTTOM;
  1465   if (tj->base() == Type::AnyPtr)
  1466     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
  1468   // Flatten all to bottom for now
  1469   switch( _AliasLevel ) {
  1470   case 0:
  1471     tj = TypePtr::BOTTOM;
  1472     break;
  1473   case 1:                       // Flatten to: oop, static, field or array
  1474     switch (tj->base()) {
  1475     //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
  1476     case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
  1477     case Type::AryPtr:   // do not distinguish arrays at all
  1478     case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
  1479     case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
  1480     case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
  1481     default: ShouldNotReachHere();
  1483     break;
  1484   case 2:                       // No collapsing at level 2; keep all splits
  1485   case 3:                       // No collapsing at level 3; keep all splits
  1486     break;
  1487   default:
  1488     Unimplemented();
  1491   offset = tj->offset();
  1492   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
  1494   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
  1495           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
  1496           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
  1497           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
  1498           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
  1499           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
  1500           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr)  ,
  1501           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
  1502   assert( tj->ptr() != TypePtr::TopPTR &&
  1503           tj->ptr() != TypePtr::AnyNull &&
  1504           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
  1505 //    assert( tj->ptr() != TypePtr::Constant ||
  1506 //            tj->base() == Type::RawPtr ||
  1507 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
  1509   return tj;
  1512 void Compile::AliasType::Init(int i, const TypePtr* at) {
  1513   _index = i;
  1514   _adr_type = at;
  1515   _field = NULL;
  1516   _element = NULL;
  1517   _is_rewritable = true; // default
  1518   const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
  1519   if (atoop != NULL && atoop->is_known_instance()) {
  1520     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
  1521     _general_index = Compile::current()->get_alias_index(gt);
  1522   } else {
  1523     _general_index = 0;
  1527 //---------------------------------print_on------------------------------------
  1528 #ifndef PRODUCT
  1529 void Compile::AliasType::print_on(outputStream* st) {
  1530   if (index() < 10)
  1531         st->print("@ <%d> ", index());
  1532   else  st->print("@ <%d>",  index());
  1533   st->print(is_rewritable() ? "   " : " RO");
  1534   int offset = adr_type()->offset();
  1535   if (offset == Type::OffsetBot)
  1536         st->print(" +any");
  1537   else  st->print(" +%-3d", offset);
  1538   st->print(" in ");
  1539   adr_type()->dump_on(st);
  1540   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
  1541   if (field() != NULL && tjp) {
  1542     if (tjp->klass()  != field()->holder() ||
  1543         tjp->offset() != field()->offset_in_bytes()) {
  1544       st->print(" != ");
  1545       field()->print();
  1546       st->print(" ***");
  1551 void print_alias_types() {
  1552   Compile* C = Compile::current();
  1553   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
  1554   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
  1555     C->alias_type(idx)->print_on(tty);
  1556     tty->cr();
  1559 #endif
  1562 //----------------------------probe_alias_cache--------------------------------
  1563 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
  1564   intptr_t key = (intptr_t) adr_type;
  1565   key ^= key >> logAliasCacheSize;
  1566   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
  1570 //-----------------------------grow_alias_types--------------------------------
  1571 void Compile::grow_alias_types() {
  1572   const int old_ats  = _max_alias_types; // how many before?
  1573   const int new_ats  = old_ats;          // how many more?
  1574   const int grow_ats = old_ats+new_ats;  // how many now?
  1575   _max_alias_types = grow_ats;
  1576   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
  1577   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
  1578   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
  1579   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
  1583 //--------------------------------find_alias_type------------------------------
  1584 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
  1585   if (_AliasLevel == 0)
  1586     return alias_type(AliasIdxBot);
  1588   AliasCacheEntry* ace = probe_alias_cache(adr_type);
  1589   if (ace->_adr_type == adr_type) {
  1590     return alias_type(ace->_index);
  1593   // Handle special cases.
  1594   if (adr_type == NULL)             return alias_type(AliasIdxTop);
  1595   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
  1597   // Do it the slow way.
  1598   const TypePtr* flat = flatten_alias_type(adr_type);
  1600 #ifdef ASSERT
  1601   assert(flat == flatten_alias_type(flat), "idempotent");
  1602   assert(flat != TypePtr::BOTTOM,     "cannot alias-analyze an untyped ptr");
  1603   if (flat->isa_oopptr() && !flat->isa_klassptr()) {
  1604     const TypeOopPtr* foop = flat->is_oopptr();
  1605     // Scalarizable allocations have exact klass always.
  1606     bool exact = !foop->klass_is_exact() || foop->is_known_instance();
  1607     const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
  1608     assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type");
  1610   assert(flat == flatten_alias_type(flat), "exact bit doesn't matter");
  1611 #endif
  1613   int idx = AliasIdxTop;
  1614   for (int i = 0; i < num_alias_types(); i++) {
  1615     if (alias_type(i)->adr_type() == flat) {
  1616       idx = i;
  1617       break;
  1621   if (idx == AliasIdxTop) {
  1622     if (no_create)  return NULL;
  1623     // Grow the array if necessary.
  1624     if (_num_alias_types == _max_alias_types)  grow_alias_types();
  1625     // Add a new alias type.
  1626     idx = _num_alias_types++;
  1627     _alias_types[idx]->Init(idx, flat);
  1628     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
  1629     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
  1630     if (flat->isa_instptr()) {
  1631       if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
  1632           && flat->is_instptr()->klass() == env()->Class_klass())
  1633         alias_type(idx)->set_rewritable(false);
  1635     if (flat->isa_aryptr()) {
  1636 #ifdef ASSERT
  1637       const int header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
  1638       // (T_BYTE has the weakest alignment and size restrictions...)
  1639       assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
  1640 #endif
  1641       if (flat->offset() == TypePtr::OffsetBot) {
  1642         alias_type(idx)->set_element(flat->is_aryptr()->elem());
  1645     if (flat->isa_klassptr()) {
  1646       if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
  1647         alias_type(idx)->set_rewritable(false);
  1648       if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
  1649         alias_type(idx)->set_rewritable(false);
  1650       if (flat->offset() == in_bytes(Klass::access_flags_offset()))
  1651         alias_type(idx)->set_rewritable(false);
  1652       if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
  1653         alias_type(idx)->set_rewritable(false);
  1655     // %%% (We would like to finalize JavaThread::threadObj_offset(),
  1656     // but the base pointer type is not distinctive enough to identify
  1657     // references into JavaThread.)
  1659     // Check for final fields.
  1660     const TypeInstPtr* tinst = flat->isa_instptr();
  1661     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
  1662       ciField* field;
  1663       if (tinst->const_oop() != NULL &&
  1664           tinst->klass() == ciEnv::current()->Class_klass() &&
  1665           tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
  1666         // static field
  1667         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
  1668         field = k->get_field_by_offset(tinst->offset(), true);
  1669       } else {
  1670         ciInstanceKlass *k = tinst->klass()->as_instance_klass();
  1671         field = k->get_field_by_offset(tinst->offset(), false);
  1673       assert(field == NULL ||
  1674              original_field == NULL ||
  1675              (field->holder() == original_field->holder() &&
  1676               field->offset() == original_field->offset() &&
  1677               field->is_static() == original_field->is_static()), "wrong field?");
  1678       // Set field() and is_rewritable() attributes.
  1679       if (field != NULL)  alias_type(idx)->set_field(field);
  1683   // Fill the cache for next time.
  1684   ace->_adr_type = adr_type;
  1685   ace->_index    = idx;
  1686   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
  1688   // Might as well try to fill the cache for the flattened version, too.
  1689   AliasCacheEntry* face = probe_alias_cache(flat);
  1690   if (face->_adr_type == NULL) {
  1691     face->_adr_type = flat;
  1692     face->_index    = idx;
  1693     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
  1696   return alias_type(idx);
  1700 Compile::AliasType* Compile::alias_type(ciField* field) {
  1701   const TypeOopPtr* t;
  1702   if (field->is_static())
  1703     t = TypeInstPtr::make(field->holder()->java_mirror());
  1704   else
  1705     t = TypeOopPtr::make_from_klass_raw(field->holder());
  1706   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
  1707   assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
  1708   return atp;
  1712 //------------------------------have_alias_type--------------------------------
  1713 bool Compile::have_alias_type(const TypePtr* adr_type) {
  1714   AliasCacheEntry* ace = probe_alias_cache(adr_type);
  1715   if (ace->_adr_type == adr_type) {
  1716     return true;
  1719   // Handle special cases.
  1720   if (adr_type == NULL)             return true;
  1721   if (adr_type == TypePtr::BOTTOM)  return true;
  1723   return find_alias_type(adr_type, true, NULL) != NULL;
  1726 //-----------------------------must_alias--------------------------------------
  1727 // True if all values of the given address type are in the given alias category.
  1728 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
  1729   if (alias_idx == AliasIdxBot)         return true;  // the universal category
  1730   if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
  1731   if (alias_idx == AliasIdxTop)         return false; // the empty category
  1732   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
  1734   // the only remaining possible overlap is identity
  1735   int adr_idx = get_alias_index(adr_type);
  1736   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
  1737   assert(adr_idx == alias_idx ||
  1738          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
  1739           && adr_type                       != TypeOopPtr::BOTTOM),
  1740          "should not be testing for overlap with an unsafe pointer");
  1741   return adr_idx == alias_idx;
  1744 //------------------------------can_alias--------------------------------------
  1745 // True if any values of the given address type are in the given alias category.
  1746 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
  1747   if (alias_idx == AliasIdxTop)         return false; // the empty category
  1748   if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
  1749   if (alias_idx == AliasIdxBot)         return true;  // the universal category
  1750   if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
  1752   // the only remaining possible overlap is identity
  1753   int adr_idx = get_alias_index(adr_type);
  1754   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
  1755   return adr_idx == alias_idx;
  1760 //---------------------------pop_warm_call-------------------------------------
  1761 WarmCallInfo* Compile::pop_warm_call() {
  1762   WarmCallInfo* wci = _warm_calls;
  1763   if (wci != NULL)  _warm_calls = wci->remove_from(wci);
  1764   return wci;
  1767 //----------------------------Inline_Warm--------------------------------------
  1768 int Compile::Inline_Warm() {
  1769   // If there is room, try to inline some more warm call sites.
  1770   // %%% Do a graph index compaction pass when we think we're out of space?
  1771   if (!InlineWarmCalls)  return 0;
  1773   int calls_made_hot = 0;
  1774   int room_to_grow   = NodeCountInliningCutoff - unique();
  1775   int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
  1776   int amount_grown   = 0;
  1777   WarmCallInfo* call;
  1778   while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
  1779     int est_size = (int)call->size();
  1780     if (est_size > (room_to_grow - amount_grown)) {
  1781       // This one won't fit anyway.  Get rid of it.
  1782       call->make_cold();
  1783       continue;
  1785     call->make_hot();
  1786     calls_made_hot++;
  1787     amount_grown   += est_size;
  1788     amount_to_grow -= est_size;
  1791   if (calls_made_hot > 0)  set_major_progress();
  1792   return calls_made_hot;
  1796 //----------------------------Finish_Warm--------------------------------------
  1797 void Compile::Finish_Warm() {
  1798   if (!InlineWarmCalls)  return;
  1799   if (failing())  return;
  1800   if (warm_calls() == NULL)  return;
  1802   // Clean up loose ends, if we are out of space for inlining.
  1803   WarmCallInfo* call;
  1804   while ((call = pop_warm_call()) != NULL) {
  1805     call->make_cold();
  1809 //---------------------cleanup_loop_predicates-----------------------
  1810 // Remove the opaque nodes that protect the predicates so that all unused
  1811 // checks and uncommon_traps will be eliminated from the ideal graph
  1812 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
  1813   if (predicate_count()==0) return;
  1814   for (int i = predicate_count(); i > 0; i--) {
  1815     Node * n = predicate_opaque1_node(i-1);
  1816     assert(n->Opcode() == Op_Opaque1, "must be");
  1817     igvn.replace_node(n, n->in(1));
  1819   assert(predicate_count()==0, "should be clean!");
  1822 // StringOpts and late inlining of string methods
  1823 void Compile::inline_string_calls(bool parse_time) {
  1825     // remove useless nodes to make the usage analysis simpler
  1826     ResourceMark rm;
  1827     PhaseRemoveUseless pru(initial_gvn(), for_igvn());
  1831     ResourceMark rm;
  1832     print_method(PHASE_BEFORE_STRINGOPTS, 3);
  1833     PhaseStringOpts pso(initial_gvn(), for_igvn());
  1834     print_method(PHASE_AFTER_STRINGOPTS, 3);
  1837   // now inline anything that we skipped the first time around
  1838   if (!parse_time) {
  1839     _late_inlines_pos = _late_inlines.length();
  1842   while (_string_late_inlines.length() > 0) {
  1843     CallGenerator* cg = _string_late_inlines.pop();
  1844     cg->do_late_inline();
  1845     if (failing())  return;
  1847   _string_late_inlines.trunc_to(0);
  1850 // Late inlining of boxing methods
  1851 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
  1852   if (_boxing_late_inlines.length() > 0) {
  1853     assert(has_boxed_value(), "inconsistent");
  1855     PhaseGVN* gvn = initial_gvn();
  1856     set_inlining_incrementally(true);
  1858     assert( igvn._worklist.size() == 0, "should be done with igvn" );
  1859     for_igvn()->clear();
  1860     gvn->replace_with(&igvn);
  1862     while (_boxing_late_inlines.length() > 0) {
  1863       CallGenerator* cg = _boxing_late_inlines.pop();
  1864       cg->do_late_inline();
  1865       if (failing())  return;
  1867     _boxing_late_inlines.trunc_to(0);
  1870       ResourceMark rm;
  1871       PhaseRemoveUseless pru(gvn, for_igvn());
  1874     igvn = PhaseIterGVN(gvn);
  1875     igvn.optimize();
  1877     set_inlining_progress(false);
  1878     set_inlining_incrementally(false);
  1882 void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
  1883   assert(IncrementalInline, "incremental inlining should be on");
  1884   PhaseGVN* gvn = initial_gvn();
  1886   set_inlining_progress(false);
  1887   for_igvn()->clear();
  1888   gvn->replace_with(&igvn);
  1890   int i = 0;
  1892   for (; i <_late_inlines.length() && !inlining_progress(); i++) {
  1893     CallGenerator* cg = _late_inlines.at(i);
  1894     _late_inlines_pos = i+1;
  1895     cg->do_late_inline();
  1896     if (failing())  return;
  1898   int j = 0;
  1899   for (; i < _late_inlines.length(); i++, j++) {
  1900     _late_inlines.at_put(j, _late_inlines.at(i));
  1902   _late_inlines.trunc_to(j);
  1905     ResourceMark rm;
  1906     PhaseRemoveUseless pru(gvn, for_igvn());
  1909   igvn = PhaseIterGVN(gvn);
  1912 // Perform incremental inlining until bound on number of live nodes is reached
  1913 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
  1914   PhaseGVN* gvn = initial_gvn();
  1916   set_inlining_incrementally(true);
  1917   set_inlining_progress(true);
  1918   uint low_live_nodes = 0;
  1920   while(inlining_progress() && _late_inlines.length() > 0) {
  1922     if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
  1923       if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
  1924         // PhaseIdealLoop is expensive so we only try it once we are
  1925         // out of loop and we only try it again if the previous helped
  1926         // got the number of nodes down significantly
  1927         PhaseIdealLoop ideal_loop( igvn, false, true );
  1928         if (failing())  return;
  1929         low_live_nodes = live_nodes();
  1930         _major_progress = true;
  1933       if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
  1934         break;
  1938     inline_incrementally_one(igvn);
  1940     if (failing())  return;
  1942     igvn.optimize();
  1944     if (failing())  return;
  1947   assert( igvn._worklist.size() == 0, "should be done with igvn" );
  1949   if (_string_late_inlines.length() > 0) {
  1950     assert(has_stringbuilder(), "inconsistent");
  1951     for_igvn()->clear();
  1952     initial_gvn()->replace_with(&igvn);
  1954     inline_string_calls(false);
  1956     if (failing())  return;
  1959       ResourceMark rm;
  1960       PhaseRemoveUseless pru(initial_gvn(), for_igvn());
  1963     igvn = PhaseIterGVN(gvn);
  1965     igvn.optimize();
  1968   set_inlining_incrementally(false);
  1972 //------------------------------Optimize---------------------------------------
  1973 // Given a graph, optimize it.
  1974 void Compile::Optimize() {
  1975   TracePhase t1("optimizer", &_t_optimizer, true);
  1977 #ifndef PRODUCT
  1978   if (env()->break_at_compile()) {
  1979     BREAKPOINT;
  1982 #endif
  1984   ResourceMark rm;
  1985   int          loop_opts_cnt;
  1987   NOT_PRODUCT( verify_graph_edges(); )
  1989   print_method(PHASE_AFTER_PARSING);
  1992   // Iterative Global Value Numbering, including ideal transforms
  1993   // Initialize IterGVN with types and values from parse-time GVN
  1994   PhaseIterGVN igvn(initial_gvn());
  1996     NOT_PRODUCT( TracePhase t2("iterGVN", &_t_iterGVN, TimeCompiler); )
  1997     igvn.optimize();
  2000   print_method(PHASE_ITER_GVN1, 2);
  2002   if (failing())  return;
  2005     NOT_PRODUCT( TracePhase t2("incrementalInline", &_t_incrInline, TimeCompiler); )
  2006     inline_incrementally(igvn);
  2009   print_method(PHASE_INCREMENTAL_INLINE, 2);
  2011   if (failing())  return;
  2013   if (eliminate_boxing()) {
  2014     NOT_PRODUCT( TracePhase t2("incrementalInline", &_t_incrInline, TimeCompiler); )
  2015     // Inline valueOf() methods now.
  2016     inline_boxing_calls(igvn);
  2018     print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
  2020     if (failing())  return;
  2023   // Remove the speculative part of types and clean up the graph from
  2024   // the extra CastPP nodes whose only purpose is to carry them. Do
  2025   // that early so that optimizations are not disrupted by the extra
  2026   // CastPP nodes.
  2027   remove_speculative_types(igvn);
  2029   // No more new expensive nodes will be added to the list from here
  2030   // so keep only the actual candidates for optimizations.
  2031   cleanup_expensive_nodes(igvn);
  2033   // Perform escape analysis
  2034   if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
  2035     if (has_loops()) {
  2036       // Cleanup graph (remove dead nodes).
  2037       TracePhase t2("idealLoop", &_t_idealLoop, true);
  2038       PhaseIdealLoop ideal_loop( igvn, false, true );
  2039       if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
  2040       if (failing())  return;
  2042     ConnectionGraph::do_analysis(this, &igvn);
  2044     if (failing())  return;
  2046     // Optimize out fields loads from scalar replaceable allocations.
  2047     igvn.optimize();
  2048     print_method(PHASE_ITER_GVN_AFTER_EA, 2);
  2050     if (failing())  return;
  2052     if (congraph() != NULL && macro_count() > 0) {
  2053       NOT_PRODUCT( TracePhase t2("macroEliminate", &_t_macroEliminate, TimeCompiler); )
  2054       PhaseMacroExpand mexp(igvn);
  2055       mexp.eliminate_macro_nodes();
  2056       igvn.set_delay_transform(false);
  2058       igvn.optimize();
  2059       print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
  2061       if (failing())  return;
  2065   // Loop transforms on the ideal graph.  Range Check Elimination,
  2066   // peeling, unrolling, etc.
  2068   // Set loop opts counter
  2069   loop_opts_cnt = num_loop_opts();
  2070   if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
  2072       TracePhase t2("idealLoop", &_t_idealLoop, true);
  2073       PhaseIdealLoop ideal_loop( igvn, true );
  2074       loop_opts_cnt--;
  2075       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
  2076       if (failing())  return;
  2078     // Loop opts pass if partial peeling occurred in previous pass
  2079     if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
  2080       TracePhase t3("idealLoop", &_t_idealLoop, true);
  2081       PhaseIdealLoop ideal_loop( igvn, false );
  2082       loop_opts_cnt--;
  2083       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
  2084       if (failing())  return;
  2086     // Loop opts pass for loop-unrolling before CCP
  2087     if(major_progress() && (loop_opts_cnt > 0)) {
  2088       TracePhase t4("idealLoop", &_t_idealLoop, true);
  2089       PhaseIdealLoop ideal_loop( igvn, false );
  2090       loop_opts_cnt--;
  2091       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
  2093     if (!failing()) {
  2094       // Verify that last round of loop opts produced a valid graph
  2095       NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
  2096       PhaseIdealLoop::verify(igvn);
  2099   if (failing())  return;
  2101   // Conditional Constant Propagation;
  2102   PhaseCCP ccp( &igvn );
  2103   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
  2105     TracePhase t2("ccp", &_t_ccp, true);
  2106     ccp.do_transform();
  2108   print_method(PHASE_CPP1, 2);
  2110   assert( true, "Break here to ccp.dump_old2new_map()");
  2112   // Iterative Global Value Numbering, including ideal transforms
  2114     NOT_PRODUCT( TracePhase t2("iterGVN2", &_t_iterGVN2, TimeCompiler); )
  2115     igvn = ccp;
  2116     igvn.optimize();
  2119   print_method(PHASE_ITER_GVN2, 2);
  2121   if (failing())  return;
  2123   // Loop transforms on the ideal graph.  Range Check Elimination,
  2124   // peeling, unrolling, etc.
  2125   if(loop_opts_cnt > 0) {
  2126     debug_only( int cnt = 0; );
  2127     while(major_progress() && (loop_opts_cnt > 0)) {
  2128       TracePhase t2("idealLoop", &_t_idealLoop, true);
  2129       assert( cnt++ < 40, "infinite cycle in loop optimization" );
  2130       PhaseIdealLoop ideal_loop( igvn, true);
  2131       loop_opts_cnt--;
  2132       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
  2133       if (failing())  return;
  2138     // Verify that all previous optimizations produced a valid graph
  2139     // at least to this point, even if no loop optimizations were done.
  2140     NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
  2141     PhaseIdealLoop::verify(igvn);
  2145     NOT_PRODUCT( TracePhase t2("macroExpand", &_t_macroExpand, TimeCompiler); )
  2146     PhaseMacroExpand  mex(igvn);
  2147     if (mex.expand_macro_nodes()) {
  2148       assert(failing(), "must bail out w/ explicit message");
  2149       return;
  2153  } // (End scope of igvn; run destructor if necessary for asserts.)
  2155   dump_inlining();
  2156   // A method with only infinite loops has no edges entering loops from root
  2158     NOT_PRODUCT( TracePhase t2("graphReshape", &_t_graphReshaping, TimeCompiler); )
  2159     if (final_graph_reshaping()) {
  2160       assert(failing(), "must bail out w/ explicit message");
  2161       return;
  2165   print_method(PHASE_OPTIMIZE_FINISHED, 2);
  2169 //------------------------------Code_Gen---------------------------------------
  2170 // Given a graph, generate code for it
  2171 void Compile::Code_Gen() {
  2172   if (failing()) {
  2173     return;
  2176   // Perform instruction selection.  You might think we could reclaim Matcher
  2177   // memory PDQ, but actually the Matcher is used in generating spill code.
  2178   // Internals of the Matcher (including some VectorSets) must remain live
  2179   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
  2180   // set a bit in reclaimed memory.
  2182   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
  2183   // nodes.  Mapping is only valid at the root of each matched subtree.
  2184   NOT_PRODUCT( verify_graph_edges(); )
  2186   Matcher matcher;
  2187   _matcher = &matcher;
  2189     TracePhase t2("matcher", &_t_matcher, true);
  2190     matcher.match();
  2192   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
  2193   // nodes.  Mapping is only valid at the root of each matched subtree.
  2194   NOT_PRODUCT( verify_graph_edges(); )
  2196   // If you have too many nodes, or if matching has failed, bail out
  2197   check_node_count(0, "out of nodes matching instructions");
  2198   if (failing()) {
  2199     return;
  2202   // Build a proper-looking CFG
  2203   PhaseCFG cfg(node_arena(), root(), matcher);
  2204   _cfg = &cfg;
  2206     NOT_PRODUCT( TracePhase t2("scheduler", &_t_scheduler, TimeCompiler); )
  2207     bool success = cfg.do_global_code_motion();
  2208     if (!success) {
  2209       return;
  2212     print_method(PHASE_GLOBAL_CODE_MOTION, 2);
  2213     NOT_PRODUCT( verify_graph_edges(); )
  2214     debug_only( cfg.verify(); )
  2217   PhaseChaitin regalloc(unique(), cfg, matcher);
  2218   _regalloc = &regalloc;
  2220     TracePhase t2("regalloc", &_t_registerAllocation, true);
  2221     // Perform register allocation.  After Chaitin, use-def chains are
  2222     // no longer accurate (at spill code) and so must be ignored.
  2223     // Node->LRG->reg mappings are still accurate.
  2224     _regalloc->Register_Allocate();
  2226     // Bail out if the allocator builds too many nodes
  2227     if (failing()) {
  2228       return;
  2232   // Prior to register allocation we kept empty basic blocks in case the
  2233   // the allocator needed a place to spill.  After register allocation we
  2234   // are not adding any new instructions.  If any basic block is empty, we
  2235   // can now safely remove it.
  2237     NOT_PRODUCT( TracePhase t2("blockOrdering", &_t_blockOrdering, TimeCompiler); )
  2238     cfg.remove_empty_blocks();
  2239     if (do_freq_based_layout()) {
  2240       PhaseBlockLayout layout(cfg);
  2241     } else {
  2242       cfg.set_loop_alignment();
  2244     cfg.fixup_flow();
  2247   // Apply peephole optimizations
  2248   if( OptoPeephole ) {
  2249     NOT_PRODUCT( TracePhase t2("peephole", &_t_peephole, TimeCompiler); )
  2250     PhasePeephole peep( _regalloc, cfg);
  2251     peep.do_transform();
  2254   // Do late expand if CPU requires this.
  2255   if (Matcher::require_postalloc_expand) {
  2256     NOT_PRODUCT(TracePhase t2c("postalloc_expand", &_t_postalloc_expand, true));
  2257     cfg.postalloc_expand(_regalloc);
  2260   // Convert Nodes to instruction bits in a buffer
  2262     // %%%% workspace merge brought two timers together for one job
  2263     TracePhase t2a("output", &_t_output, true);
  2264     NOT_PRODUCT( TraceTime t2b(NULL, &_t_codeGeneration, TimeCompiler, false); )
  2265     Output();
  2268   print_method(PHASE_FINAL_CODE);
  2270   // He's dead, Jim.
  2271   _cfg     = (PhaseCFG*)0xdeadbeef;
  2272   _regalloc = (PhaseChaitin*)0xdeadbeef;
  2276 //------------------------------dump_asm---------------------------------------
  2277 // Dump formatted assembly
  2278 #ifndef PRODUCT
  2279 void Compile::dump_asm(int *pcs, uint pc_limit) {
  2280   bool cut_short = false;
  2281   tty->print_cr("#");
  2282   tty->print("#  ");  _tf->dump();  tty->cr();
  2283   tty->print_cr("#");
  2285   // For all blocks
  2286   int pc = 0x0;                 // Program counter
  2287   char starts_bundle = ' ';
  2288   _regalloc->dump_frame();
  2290   Node *n = NULL;
  2291   for (uint i = 0; i < _cfg->number_of_blocks(); i++) {
  2292     if (VMThread::should_terminate()) {
  2293       cut_short = true;
  2294       break;
  2296     Block* block = _cfg->get_block(i);
  2297     if (block->is_connector() && !Verbose) {
  2298       continue;
  2300     n = block->head();
  2301     if (pcs && n->_idx < pc_limit) {
  2302       tty->print("%3.3x   ", pcs[n->_idx]);
  2303     } else {
  2304       tty->print("      ");
  2306     block->dump_head(_cfg);
  2307     if (block->is_connector()) {
  2308       tty->print_cr("        # Empty connector block");
  2309     } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
  2310       tty->print_cr("        # Block is sole successor of call");
  2313     // For all instructions
  2314     Node *delay = NULL;
  2315     for (uint j = 0; j < block->number_of_nodes(); j++) {
  2316       if (VMThread::should_terminate()) {
  2317         cut_short = true;
  2318         break;
  2320       n = block->get_node(j);
  2321       if (valid_bundle_info(n)) {
  2322         Bundle* bundle = node_bundling(n);
  2323         if (bundle->used_in_unconditional_delay()) {
  2324           delay = n;
  2325           continue;
  2327         if (bundle->starts_bundle()) {
  2328           starts_bundle = '+';
  2332       if (WizardMode) {
  2333         n->dump();
  2336       if( !n->is_Region() &&    // Dont print in the Assembly
  2337           !n->is_Phi() &&       // a few noisely useless nodes
  2338           !n->is_Proj() &&
  2339           !n->is_MachTemp() &&
  2340           !n->is_SafePointScalarObject() &&
  2341           !n->is_Catch() &&     // Would be nice to print exception table targets
  2342           !n->is_MergeMem() &&  // Not very interesting
  2343           !n->is_top() &&       // Debug info table constants
  2344           !(n->is_Con() && !n->is_Mach())// Debug info table constants
  2345           ) {
  2346         if (pcs && n->_idx < pc_limit)
  2347           tty->print("%3.3x", pcs[n->_idx]);
  2348         else
  2349           tty->print("   ");
  2350         tty->print(" %c ", starts_bundle);
  2351         starts_bundle = ' ';
  2352         tty->print("\t");
  2353         n->format(_regalloc, tty);
  2354         tty->cr();
  2357       // If we have an instruction with a delay slot, and have seen a delay,
  2358       // then back up and print it
  2359       if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
  2360         assert(delay != NULL, "no unconditional delay instruction");
  2361         if (WizardMode) delay->dump();
  2363         if (node_bundling(delay)->starts_bundle())
  2364           starts_bundle = '+';
  2365         if (pcs && n->_idx < pc_limit)
  2366           tty->print("%3.3x", pcs[n->_idx]);
  2367         else
  2368           tty->print("   ");
  2369         tty->print(" %c ", starts_bundle);
  2370         starts_bundle = ' ';
  2371         tty->print("\t");
  2372         delay->format(_regalloc, tty);
  2373         tty->print_cr("");
  2374         delay = NULL;
  2377       // Dump the exception table as well
  2378       if( n->is_Catch() && (Verbose || WizardMode) ) {
  2379         // Print the exception table for this offset
  2380         _handler_table.print_subtable_for(pc);
  2384     if (pcs && n->_idx < pc_limit)
  2385       tty->print_cr("%3.3x", pcs[n->_idx]);
  2386     else
  2387       tty->print_cr("");
  2389     assert(cut_short || delay == NULL, "no unconditional delay branch");
  2391   } // End of per-block dump
  2392   tty->print_cr("");
  2394   if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
  2396 #endif
  2398 //------------------------------Final_Reshape_Counts---------------------------
  2399 // This class defines counters to help identify when a method
  2400 // may/must be executed using hardware with only 24-bit precision.
  2401 struct Final_Reshape_Counts : public StackObj {
  2402   int  _call_count;             // count non-inlined 'common' calls
  2403   int  _float_count;            // count float ops requiring 24-bit precision
  2404   int  _double_count;           // count double ops requiring more precision
  2405   int  _java_call_count;        // count non-inlined 'java' calls
  2406   int  _inner_loop_count;       // count loops which need alignment
  2407   VectorSet _visited;           // Visitation flags
  2408   Node_List _tests;             // Set of IfNodes & PCTableNodes
  2410   Final_Reshape_Counts() :
  2411     _call_count(0), _float_count(0), _double_count(0),
  2412     _java_call_count(0), _inner_loop_count(0),
  2413     _visited( Thread::current()->resource_area() ) { }
  2415   void inc_call_count  () { _call_count  ++; }
  2416   void inc_float_count () { _float_count ++; }
  2417   void inc_double_count() { _double_count++; }
  2418   void inc_java_call_count() { _java_call_count++; }
  2419   void inc_inner_loop_count() { _inner_loop_count++; }
  2421   int  get_call_count  () const { return _call_count  ; }
  2422   int  get_float_count () const { return _float_count ; }
  2423   int  get_double_count() const { return _double_count; }
  2424   int  get_java_call_count() const { return _java_call_count; }
  2425   int  get_inner_loop_count() const { return _inner_loop_count; }
  2426 };
  2428 #ifdef ASSERT
  2429 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
  2430   ciInstanceKlass *k = tp->klass()->as_instance_klass();
  2431   // Make sure the offset goes inside the instance layout.
  2432   return k->contains_field_offset(tp->offset());
  2433   // Note that OffsetBot and OffsetTop are very negative.
  2435 #endif
  2437 // Eliminate trivially redundant StoreCMs and accumulate their
  2438 // precedence edges.
  2439 void Compile::eliminate_redundant_card_marks(Node* n) {
  2440   assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
  2441   if (n->in(MemNode::Address)->outcnt() > 1) {
  2442     // There are multiple users of the same address so it might be
  2443     // possible to eliminate some of the StoreCMs
  2444     Node* mem = n->in(MemNode::Memory);
  2445     Node* adr = n->in(MemNode::Address);
  2446     Node* val = n->in(MemNode::ValueIn);
  2447     Node* prev = n;
  2448     bool done = false;
  2449     // Walk the chain of StoreCMs eliminating ones that match.  As
  2450     // long as it's a chain of single users then the optimization is
  2451     // safe.  Eliminating partially redundant StoreCMs would require
  2452     // cloning copies down the other paths.
  2453     while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
  2454       if (adr == mem->in(MemNode::Address) &&
  2455           val == mem->in(MemNode::ValueIn)) {
  2456         // redundant StoreCM
  2457         if (mem->req() > MemNode::OopStore) {
  2458           // Hasn't been processed by this code yet.
  2459           n->add_prec(mem->in(MemNode::OopStore));
  2460         } else {
  2461           // Already converted to precedence edge
  2462           for (uint i = mem->req(); i < mem->len(); i++) {
  2463             // Accumulate any precedence edges
  2464             if (mem->in(i) != NULL) {
  2465               n->add_prec(mem->in(i));
  2468           // Everything above this point has been processed.
  2469           done = true;
  2471         // Eliminate the previous StoreCM
  2472         prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
  2473         assert(mem->outcnt() == 0, "should be dead");
  2474         mem->disconnect_inputs(NULL, this);
  2475       } else {
  2476         prev = mem;
  2478       mem = prev->in(MemNode::Memory);
  2483 //------------------------------final_graph_reshaping_impl----------------------
  2484 // Implement items 1-5 from final_graph_reshaping below.
  2485 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
  2487   if ( n->outcnt() == 0 ) return; // dead node
  2488   uint nop = n->Opcode();
  2490   // Check for 2-input instruction with "last use" on right input.
  2491   // Swap to left input.  Implements item (2).
  2492   if( n->req() == 3 &&          // two-input instruction
  2493       n->in(1)->outcnt() > 1 && // left use is NOT a last use
  2494       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
  2495       n->in(2)->outcnt() == 1 &&// right use IS a last use
  2496       !n->in(2)->is_Con() ) {   // right use is not a constant
  2497     // Check for commutative opcode
  2498     switch( nop ) {
  2499     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
  2500     case Op_MaxI:  case Op_MinI:
  2501     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
  2502     case Op_AndL:  case Op_XorL:  case Op_OrL:
  2503     case Op_AndI:  case Op_XorI:  case Op_OrI: {
  2504       // Move "last use" input to left by swapping inputs
  2505       n->swap_edges(1, 2);
  2506       break;
  2508     default:
  2509       break;
  2513 #ifdef ASSERT
  2514   if( n->is_Mem() ) {
  2515     int alias_idx = get_alias_index(n->as_Mem()->adr_type());
  2516     assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
  2517             // oop will be recorded in oop map if load crosses safepoint
  2518             n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
  2519                              LoadNode::is_immutable_value(n->in(MemNode::Address))),
  2520             "raw memory operations should have control edge");
  2522 #endif
  2523   // Count FPU ops and common calls, implements item (3)
  2524   switch( nop ) {
  2525   // Count all float operations that may use FPU
  2526   case Op_AddF:
  2527   case Op_SubF:
  2528   case Op_MulF:
  2529   case Op_DivF:
  2530   case Op_NegF:
  2531   case Op_ModF:
  2532   case Op_ConvI2F:
  2533   case Op_ConF:
  2534   case Op_CmpF:
  2535   case Op_CmpF3:
  2536   // case Op_ConvL2F: // longs are split into 32-bit halves
  2537     frc.inc_float_count();
  2538     break;
  2540   case Op_ConvF2D:
  2541   case Op_ConvD2F:
  2542     frc.inc_float_count();
  2543     frc.inc_double_count();
  2544     break;
  2546   // Count all double operations that may use FPU
  2547   case Op_AddD:
  2548   case Op_SubD:
  2549   case Op_MulD:
  2550   case Op_DivD:
  2551   case Op_NegD:
  2552   case Op_ModD:
  2553   case Op_ConvI2D:
  2554   case Op_ConvD2I:
  2555   // case Op_ConvL2D: // handled by leaf call
  2556   // case Op_ConvD2L: // handled by leaf call
  2557   case Op_ConD:
  2558   case Op_CmpD:
  2559   case Op_CmpD3:
  2560     frc.inc_double_count();
  2561     break;
  2562   case Op_Opaque1:              // Remove Opaque Nodes before matching
  2563   case Op_Opaque2:              // Remove Opaque Nodes before matching
  2564     n->subsume_by(n->in(1), this);
  2565     break;
  2566   case Op_CallStaticJava:
  2567   case Op_CallJava:
  2568   case Op_CallDynamicJava:
  2569     frc.inc_java_call_count(); // Count java call site;
  2570   case Op_CallRuntime:
  2571   case Op_CallLeaf:
  2572   case Op_CallLeafNoFP: {
  2573     assert( n->is_Call(), "" );
  2574     CallNode *call = n->as_Call();
  2575     // Count call sites where the FP mode bit would have to be flipped.
  2576     // Do not count uncommon runtime calls:
  2577     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
  2578     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
  2579     if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
  2580       frc.inc_call_count();   // Count the call site
  2581     } else {                  // See if uncommon argument is shared
  2582       Node *n = call->in(TypeFunc::Parms);
  2583       int nop = n->Opcode();
  2584       // Clone shared simple arguments to uncommon calls, item (1).
  2585       if( n->outcnt() > 1 &&
  2586           !n->is_Proj() &&
  2587           nop != Op_CreateEx &&
  2588           nop != Op_CheckCastPP &&
  2589           nop != Op_DecodeN &&
  2590           nop != Op_DecodeNKlass &&
  2591           !n->is_Mem() ) {
  2592         Node *x = n->clone();
  2593         call->set_req( TypeFunc::Parms, x );
  2596     break;
  2599   case Op_StoreD:
  2600   case Op_LoadD:
  2601   case Op_LoadD_unaligned:
  2602     frc.inc_double_count();
  2603     goto handle_mem;
  2604   case Op_StoreF:
  2605   case Op_LoadF:
  2606     frc.inc_float_count();
  2607     goto handle_mem;
  2609   case Op_StoreCM:
  2611       // Convert OopStore dependence into precedence edge
  2612       Node* prec = n->in(MemNode::OopStore);
  2613       n->del_req(MemNode::OopStore);
  2614       n->add_prec(prec);
  2615       eliminate_redundant_card_marks(n);
  2618     // fall through
  2620   case Op_StoreB:
  2621   case Op_StoreC:
  2622   case Op_StorePConditional:
  2623   case Op_StoreI:
  2624   case Op_StoreL:
  2625   case Op_StoreIConditional:
  2626   case Op_StoreLConditional:
  2627   case Op_CompareAndSwapI:
  2628   case Op_CompareAndSwapL:
  2629   case Op_CompareAndSwapP:
  2630   case Op_CompareAndSwapN:
  2631   case Op_GetAndAddI:
  2632   case Op_GetAndAddL:
  2633   case Op_GetAndSetI:
  2634   case Op_GetAndSetL:
  2635   case Op_GetAndSetP:
  2636   case Op_GetAndSetN:
  2637   case Op_StoreP:
  2638   case Op_StoreN:
  2639   case Op_StoreNKlass:
  2640   case Op_LoadB:
  2641   case Op_LoadUB:
  2642   case Op_LoadUS:
  2643   case Op_LoadI:
  2644   case Op_LoadKlass:
  2645   case Op_LoadNKlass:
  2646   case Op_LoadL:
  2647   case Op_LoadL_unaligned:
  2648   case Op_LoadPLocked:
  2649   case Op_LoadP:
  2650   case Op_LoadN:
  2651   case Op_LoadRange:
  2652   case Op_LoadS: {
  2653   handle_mem:
  2654 #ifdef ASSERT
  2655     if( VerifyOptoOopOffsets ) {
  2656       assert( n->is_Mem(), "" );
  2657       MemNode *mem  = (MemNode*)n;
  2658       // Check to see if address types have grounded out somehow.
  2659       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
  2660       assert( !tp || oop_offset_is_sane(tp), "" );
  2662 #endif
  2663     break;
  2666   case Op_AddP: {               // Assert sane base pointers
  2667     Node *addp = n->in(AddPNode::Address);
  2668     assert( !addp->is_AddP() ||
  2669             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
  2670             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
  2671             "Base pointers must match" );
  2672 #ifdef _LP64
  2673     if ((UseCompressedOops || UseCompressedClassPointers) &&
  2674         addp->Opcode() == Op_ConP &&
  2675         addp == n->in(AddPNode::Base) &&
  2676         n->in(AddPNode::Offset)->is_Con()) {
  2677       // Use addressing with narrow klass to load with offset on x86.
  2678       // On sparc loading 32-bits constant and decoding it have less
  2679       // instructions (4) then load 64-bits constant (7).
  2680       // Do this transformation here since IGVN will convert ConN back to ConP.
  2681       const Type* t = addp->bottom_type();
  2682       if (t->isa_oopptr() || t->isa_klassptr()) {
  2683         Node* nn = NULL;
  2685         int op = t->isa_oopptr() ? Op_ConN : Op_ConNKlass;
  2687         // Look for existing ConN node of the same exact type.
  2688         Node* r  = root();
  2689         uint cnt = r->outcnt();
  2690         for (uint i = 0; i < cnt; i++) {
  2691           Node* m = r->raw_out(i);
  2692           if (m!= NULL && m->Opcode() == op &&
  2693               m->bottom_type()->make_ptr() == t) {
  2694             nn = m;
  2695             break;
  2698         if (nn != NULL) {
  2699           // Decode a narrow oop to match address
  2700           // [R12 + narrow_oop_reg<<3 + offset]
  2701           if (t->isa_oopptr()) {
  2702             nn = new (this) DecodeNNode(nn, t);
  2703           } else {
  2704             nn = new (this) DecodeNKlassNode(nn, t);
  2706           n->set_req(AddPNode::Base, nn);
  2707           n->set_req(AddPNode::Address, nn);
  2708           if (addp->outcnt() == 0) {
  2709             addp->disconnect_inputs(NULL, this);
  2714 #endif
  2715     break;
  2718 #ifdef _LP64
  2719   case Op_CastPP:
  2720     if (n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
  2721       Node* in1 = n->in(1);
  2722       const Type* t = n->bottom_type();
  2723       Node* new_in1 = in1->clone();
  2724       new_in1->as_DecodeN()->set_type(t);
  2726       if (!Matcher::narrow_oop_use_complex_address()) {
  2727         //
  2728         // x86, ARM and friends can handle 2 adds in addressing mode
  2729         // and Matcher can fold a DecodeN node into address by using
  2730         // a narrow oop directly and do implicit NULL check in address:
  2731         //
  2732         // [R12 + narrow_oop_reg<<3 + offset]
  2733         // NullCheck narrow_oop_reg
  2734         //
  2735         // On other platforms (Sparc) we have to keep new DecodeN node and
  2736         // use it to do implicit NULL check in address:
  2737         //
  2738         // decode_not_null narrow_oop_reg, base_reg
  2739         // [base_reg + offset]
  2740         // NullCheck base_reg
  2741         //
  2742         // Pin the new DecodeN node to non-null path on these platform (Sparc)
  2743         // to keep the information to which NULL check the new DecodeN node
  2744         // corresponds to use it as value in implicit_null_check().
  2745         //
  2746         new_in1->set_req(0, n->in(0));
  2749       n->subsume_by(new_in1, this);
  2750       if (in1->outcnt() == 0) {
  2751         in1->disconnect_inputs(NULL, this);
  2754     break;
  2756   case Op_CmpP:
  2757     // Do this transformation here to preserve CmpPNode::sub() and
  2758     // other TypePtr related Ideal optimizations (for example, ptr nullness).
  2759     if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
  2760       Node* in1 = n->in(1);
  2761       Node* in2 = n->in(2);
  2762       if (!in1->is_DecodeNarrowPtr()) {
  2763         in2 = in1;
  2764         in1 = n->in(2);
  2766       assert(in1->is_DecodeNarrowPtr(), "sanity");
  2768       Node* new_in2 = NULL;
  2769       if (in2->is_DecodeNarrowPtr()) {
  2770         assert(in2->Opcode() == in1->Opcode(), "must be same node type");
  2771         new_in2 = in2->in(1);
  2772       } else if (in2->Opcode() == Op_ConP) {
  2773         const Type* t = in2->bottom_type();
  2774         if (t == TypePtr::NULL_PTR) {
  2775           assert(in1->is_DecodeN(), "compare klass to null?");
  2776           // Don't convert CmpP null check into CmpN if compressed
  2777           // oops implicit null check is not generated.
  2778           // This will allow to generate normal oop implicit null check.
  2779           if (Matcher::gen_narrow_oop_implicit_null_checks())
  2780             new_in2 = ConNode::make(this, TypeNarrowOop::NULL_PTR);
  2781           //
  2782           // This transformation together with CastPP transformation above
  2783           // will generated code for implicit NULL checks for compressed oops.
  2784           //
  2785           // The original code after Optimize()
  2786           //
  2787           //    LoadN memory, narrow_oop_reg
  2788           //    decode narrow_oop_reg, base_reg
  2789           //    CmpP base_reg, NULL
  2790           //    CastPP base_reg // NotNull
  2791           //    Load [base_reg + offset], val_reg
  2792           //
  2793           // after these transformations will be
  2794           //
  2795           //    LoadN memory, narrow_oop_reg
  2796           //    CmpN narrow_oop_reg, NULL
  2797           //    decode_not_null narrow_oop_reg, base_reg
  2798           //    Load [base_reg + offset], val_reg
  2799           //
  2800           // and the uncommon path (== NULL) will use narrow_oop_reg directly
  2801           // since narrow oops can be used in debug info now (see the code in
  2802           // final_graph_reshaping_walk()).
  2803           //
  2804           // At the end the code will be matched to
  2805           // on x86:
  2806           //
  2807           //    Load_narrow_oop memory, narrow_oop_reg
  2808           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
  2809           //    NullCheck narrow_oop_reg
  2810           //
  2811           // and on sparc:
  2812           //
  2813           //    Load_narrow_oop memory, narrow_oop_reg
  2814           //    decode_not_null narrow_oop_reg, base_reg
  2815           //    Load [base_reg + offset], val_reg
  2816           //    NullCheck base_reg
  2817           //
  2818         } else if (t->isa_oopptr()) {
  2819           new_in2 = ConNode::make(this, t->make_narrowoop());
  2820         } else if (t->isa_klassptr()) {
  2821           new_in2 = ConNode::make(this, t->make_narrowklass());
  2824       if (new_in2 != NULL) {
  2825         Node* cmpN = new (this) CmpNNode(in1->in(1), new_in2);
  2826         n->subsume_by(cmpN, this);
  2827         if (in1->outcnt() == 0) {
  2828           in1->disconnect_inputs(NULL, this);
  2830         if (in2->outcnt() == 0) {
  2831           in2->disconnect_inputs(NULL, this);
  2835     break;
  2837   case Op_DecodeN:
  2838   case Op_DecodeNKlass:
  2839     assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
  2840     // DecodeN could be pinned when it can't be fold into
  2841     // an address expression, see the code for Op_CastPP above.
  2842     assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
  2843     break;
  2845   case Op_EncodeP:
  2846   case Op_EncodePKlass: {
  2847     Node* in1 = n->in(1);
  2848     if (in1->is_DecodeNarrowPtr()) {
  2849       n->subsume_by(in1->in(1), this);
  2850     } else if (in1->Opcode() == Op_ConP) {
  2851       const Type* t = in1->bottom_type();
  2852       if (t == TypePtr::NULL_PTR) {
  2853         assert(t->isa_oopptr(), "null klass?");
  2854         n->subsume_by(ConNode::make(this, TypeNarrowOop::NULL_PTR), this);
  2855       } else if (t->isa_oopptr()) {
  2856         n->subsume_by(ConNode::make(this, t->make_narrowoop()), this);
  2857       } else if (t->isa_klassptr()) {
  2858         n->subsume_by(ConNode::make(this, t->make_narrowklass()), this);
  2861     if (in1->outcnt() == 0) {
  2862       in1->disconnect_inputs(NULL, this);
  2864     break;
  2867   case Op_Proj: {
  2868     if (OptimizeStringConcat) {
  2869       ProjNode* p = n->as_Proj();
  2870       if (p->_is_io_use) {
  2871         // Separate projections were used for the exception path which
  2872         // are normally removed by a late inline.  If it wasn't inlined
  2873         // then they will hang around and should just be replaced with
  2874         // the original one.
  2875         Node* proj = NULL;
  2876         // Replace with just one
  2877         for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
  2878           Node *use = i.get();
  2879           if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
  2880             proj = use;
  2881             break;
  2884         assert(proj != NULL, "must be found");
  2885         p->subsume_by(proj, this);
  2888     break;
  2891   case Op_Phi:
  2892     if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
  2893       // The EncodeP optimization may create Phi with the same edges
  2894       // for all paths. It is not handled well by Register Allocator.
  2895       Node* unique_in = n->in(1);
  2896       assert(unique_in != NULL, "");
  2897       uint cnt = n->req();
  2898       for (uint i = 2; i < cnt; i++) {
  2899         Node* m = n->in(i);
  2900         assert(m != NULL, "");
  2901         if (unique_in != m)
  2902           unique_in = NULL;
  2904       if (unique_in != NULL) {
  2905         n->subsume_by(unique_in, this);
  2908     break;
  2910 #endif
  2912   case Op_ModI:
  2913     if (UseDivMod) {
  2914       // Check if a%b and a/b both exist
  2915       Node* d = n->find_similar(Op_DivI);
  2916       if (d) {
  2917         // Replace them with a fused divmod if supported
  2918         if (Matcher::has_match_rule(Op_DivModI)) {
  2919           DivModINode* divmod = DivModINode::make(this, n);
  2920           d->subsume_by(divmod->div_proj(), this);
  2921           n->subsume_by(divmod->mod_proj(), this);
  2922         } else {
  2923           // replace a%b with a-((a/b)*b)
  2924           Node* mult = new (this) MulINode(d, d->in(2));
  2925           Node* sub  = new (this) SubINode(d->in(1), mult);
  2926           n->subsume_by(sub, this);
  2930     break;
  2932   case Op_ModL:
  2933     if (UseDivMod) {
  2934       // Check if a%b and a/b both exist
  2935       Node* d = n->find_similar(Op_DivL);
  2936       if (d) {
  2937         // Replace them with a fused divmod if supported
  2938         if (Matcher::has_match_rule(Op_DivModL)) {
  2939           DivModLNode* divmod = DivModLNode::make(this, n);
  2940           d->subsume_by(divmod->div_proj(), this);
  2941           n->subsume_by(divmod->mod_proj(), this);
  2942         } else {
  2943           // replace a%b with a-((a/b)*b)
  2944           Node* mult = new (this) MulLNode(d, d->in(2));
  2945           Node* sub  = new (this) SubLNode(d->in(1), mult);
  2946           n->subsume_by(sub, this);
  2950     break;
  2952   case Op_LoadVector:
  2953   case Op_StoreVector:
  2954     break;
  2956   case Op_PackB:
  2957   case Op_PackS:
  2958   case Op_PackI:
  2959   case Op_PackF:
  2960   case Op_PackL:
  2961   case Op_PackD:
  2962     if (n->req()-1 > 2) {
  2963       // Replace many operand PackNodes with a binary tree for matching
  2964       PackNode* p = (PackNode*) n;
  2965       Node* btp = p->binary_tree_pack(this, 1, n->req());
  2966       n->subsume_by(btp, this);
  2968     break;
  2969   case Op_Loop:
  2970   case Op_CountedLoop:
  2971     if (n->as_Loop()->is_inner_loop()) {
  2972       frc.inc_inner_loop_count();
  2974     break;
  2975   case Op_LShiftI:
  2976   case Op_RShiftI:
  2977   case Op_URShiftI:
  2978   case Op_LShiftL:
  2979   case Op_RShiftL:
  2980   case Op_URShiftL:
  2981     if (Matcher::need_masked_shift_count) {
  2982       // The cpu's shift instructions don't restrict the count to the
  2983       // lower 5/6 bits. We need to do the masking ourselves.
  2984       Node* in2 = n->in(2);
  2985       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
  2986       const TypeInt* t = in2->find_int_type();
  2987       if (t != NULL && t->is_con()) {
  2988         juint shift = t->get_con();
  2989         if (shift > mask) { // Unsigned cmp
  2990           n->set_req(2, ConNode::make(this, TypeInt::make(shift & mask)));
  2992       } else {
  2993         if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
  2994           Node* shift = new (this) AndINode(in2, ConNode::make(this, TypeInt::make(mask)));
  2995           n->set_req(2, shift);
  2998       if (in2->outcnt() == 0) { // Remove dead node
  2999         in2->disconnect_inputs(NULL, this);
  3002     break;
  3003   case Op_MemBarStoreStore:
  3004   case Op_MemBarRelease:
  3005     // Break the link with AllocateNode: it is no longer useful and
  3006     // confuses register allocation.
  3007     if (n->req() > MemBarNode::Precedent) {
  3008       n->set_req(MemBarNode::Precedent, top());
  3010     break;
  3011     // Must set a control edge on all nodes that produce a FlagsProj
  3012     // so they can't escape the block that consumes the flags.
  3013     // Must also set the non throwing branch as the control
  3014     // for all nodes that depends on the result. Unless the node
  3015     // already have a control that isn't the control of the
  3016     // flag producer
  3017   case Op_FlagsProj:
  3019       MathExactNode* math = (MathExactNode*)  n->in(0);
  3020       Node* ctrl = math->control_node();
  3021       Node* non_throwing = math->non_throwing_branch();
  3022       math->set_req(0, ctrl);
  3024       Node* result = math->result_node();
  3025       if (result != NULL) {
  3026         for (DUIterator_Fast jmax, j = result->fast_outs(jmax); j < jmax; j++) {
  3027           Node* out = result->fast_out(j);
  3028           // Phi nodes shouldn't be moved. They would only match below if they
  3029           // had the same control as the MathExactNode. The only time that
  3030           // would happen is if the Phi is also an input to the MathExact
  3031           //
  3032           // Cmp nodes shouldn't have control set at all.
  3033           if (out->is_Phi() ||
  3034               out->is_Cmp()) {
  3035             continue;
  3038           if (out->in(0) == NULL) {
  3039             out->set_req(0, non_throwing);
  3040           } else if (out->in(0) == ctrl) {
  3041             out->set_req(0, non_throwing);
  3046     break;
  3047   default:
  3048     assert( !n->is_Call(), "" );
  3049     assert( !n->is_Mem(), "" );
  3050     break;
  3053   // Collect CFG split points
  3054   if (n->is_MultiBranch())
  3055     frc._tests.push(n);
  3058 //------------------------------final_graph_reshaping_walk---------------------
  3059 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
  3060 // requires that the walk visits a node's inputs before visiting the node.
  3061 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
  3062   ResourceArea *area = Thread::current()->resource_area();
  3063   Unique_Node_List sfpt(area);
  3065   frc._visited.set(root->_idx); // first, mark node as visited
  3066   uint cnt = root->req();
  3067   Node *n = root;
  3068   uint  i = 0;
  3069   while (true) {
  3070     if (i < cnt) {
  3071       // Place all non-visited non-null inputs onto stack
  3072       Node* m = n->in(i);
  3073       ++i;
  3074       if (m != NULL && !frc._visited.test_set(m->_idx)) {
  3075         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL)
  3076           sfpt.push(m);
  3077         cnt = m->req();
  3078         nstack.push(n, i); // put on stack parent and next input's index
  3079         n = m;
  3080         i = 0;
  3082     } else {
  3083       // Now do post-visit work
  3084       final_graph_reshaping_impl( n, frc );
  3085       if (nstack.is_empty())
  3086         break;             // finished
  3087       n = nstack.node();   // Get node from stack
  3088       cnt = n->req();
  3089       i = nstack.index();
  3090       nstack.pop();        // Shift to the next node on stack
  3094   // Skip next transformation if compressed oops are not used.
  3095   if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
  3096       (!UseCompressedOops && !UseCompressedClassPointers))
  3097     return;
  3099   // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
  3100   // It could be done for an uncommon traps or any safepoints/calls
  3101   // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
  3102   while (sfpt.size() > 0) {
  3103     n = sfpt.pop();
  3104     JVMState *jvms = n->as_SafePoint()->jvms();
  3105     assert(jvms != NULL, "sanity");
  3106     int start = jvms->debug_start();
  3107     int end   = n->req();
  3108     bool is_uncommon = (n->is_CallStaticJava() &&
  3109                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
  3110     for (int j = start; j < end; j++) {
  3111       Node* in = n->in(j);
  3112       if (in->is_DecodeNarrowPtr()) {
  3113         bool safe_to_skip = true;
  3114         if (!is_uncommon ) {
  3115           // Is it safe to skip?
  3116           for (uint i = 0; i < in->outcnt(); i++) {
  3117             Node* u = in->raw_out(i);
  3118             if (!u->is_SafePoint() ||
  3119                  u->is_Call() && u->as_Call()->has_non_debug_use(n)) {
  3120               safe_to_skip = false;
  3124         if (safe_to_skip) {
  3125           n->set_req(j, in->in(1));
  3127         if (in->outcnt() == 0) {
  3128           in->disconnect_inputs(NULL, this);
  3135 //------------------------------final_graph_reshaping--------------------------
  3136 // Final Graph Reshaping.
  3137 //
  3138 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
  3139 //     and not commoned up and forced early.  Must come after regular
  3140 //     optimizations to avoid GVN undoing the cloning.  Clone constant
  3141 //     inputs to Loop Phis; these will be split by the allocator anyways.
  3142 //     Remove Opaque nodes.
  3143 // (2) Move last-uses by commutative operations to the left input to encourage
  3144 //     Intel update-in-place two-address operations and better register usage
  3145 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
  3146 //     calls canonicalizing them back.
  3147 // (3) Count the number of double-precision FP ops, single-precision FP ops
  3148 //     and call sites.  On Intel, we can get correct rounding either by
  3149 //     forcing singles to memory (requires extra stores and loads after each
  3150 //     FP bytecode) or we can set a rounding mode bit (requires setting and
  3151 //     clearing the mode bit around call sites).  The mode bit is only used
  3152 //     if the relative frequency of single FP ops to calls is low enough.
  3153 //     This is a key transform for SPEC mpeg_audio.
  3154 // (4) Detect infinite loops; blobs of code reachable from above but not
  3155 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
  3156 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
  3157 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
  3158 //     Detection is by looking for IfNodes where only 1 projection is
  3159 //     reachable from below or CatchNodes missing some targets.
  3160 // (5) Assert for insane oop offsets in debug mode.
  3162 bool Compile::final_graph_reshaping() {
  3163   // an infinite loop may have been eliminated by the optimizer,
  3164   // in which case the graph will be empty.
  3165   if (root()->req() == 1) {
  3166     record_method_not_compilable("trivial infinite loop");
  3167     return true;
  3170   // Expensive nodes have their control input set to prevent the GVN
  3171   // from freely commoning them. There's no GVN beyond this point so
  3172   // no need to keep the control input. We want the expensive nodes to
  3173   // be freely moved to the least frequent code path by gcm.
  3174   assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
  3175   for (int i = 0; i < expensive_count(); i++) {
  3176     _expensive_nodes->at(i)->set_req(0, NULL);
  3179   Final_Reshape_Counts frc;
  3181   // Visit everybody reachable!
  3182   // Allocate stack of size C->unique()/2 to avoid frequent realloc
  3183   Node_Stack nstack(unique() >> 1);
  3184   final_graph_reshaping_walk(nstack, root(), frc);
  3186   // Check for unreachable (from below) code (i.e., infinite loops).
  3187   for( uint i = 0; i < frc._tests.size(); i++ ) {
  3188     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
  3189     // Get number of CFG targets.
  3190     // Note that PCTables include exception targets after calls.
  3191     uint required_outcnt = n->required_outcnt();
  3192     if (n->outcnt() != required_outcnt) {
  3193       // Check for a few special cases.  Rethrow Nodes never take the
  3194       // 'fall-thru' path, so expected kids is 1 less.
  3195       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
  3196         if (n->in(0)->in(0)->is_Call()) {
  3197           CallNode *call = n->in(0)->in(0)->as_Call();
  3198           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
  3199             required_outcnt--;      // Rethrow always has 1 less kid
  3200           } else if (call->req() > TypeFunc::Parms &&
  3201                      call->is_CallDynamicJava()) {
  3202             // Check for null receiver. In such case, the optimizer has
  3203             // detected that the virtual call will always result in a null
  3204             // pointer exception. The fall-through projection of this CatchNode
  3205             // will not be populated.
  3206             Node *arg0 = call->in(TypeFunc::Parms);
  3207             if (arg0->is_Type() &&
  3208                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
  3209               required_outcnt--;
  3211           } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
  3212                      call->req() > TypeFunc::Parms+1 &&
  3213                      call->is_CallStaticJava()) {
  3214             // Check for negative array length. In such case, the optimizer has
  3215             // detected that the allocation attempt will always result in an
  3216             // exception. There is no fall-through projection of this CatchNode .
  3217             Node *arg1 = call->in(TypeFunc::Parms+1);
  3218             if (arg1->is_Type() &&
  3219                 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
  3220               required_outcnt--;
  3225       // Recheck with a better notion of 'required_outcnt'
  3226       if (n->outcnt() != required_outcnt) {
  3227         record_method_not_compilable("malformed control flow");
  3228         return true;            // Not all targets reachable!
  3231     // Check that I actually visited all kids.  Unreached kids
  3232     // must be infinite loops.
  3233     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
  3234       if (!frc._visited.test(n->fast_out(j)->_idx)) {
  3235         record_method_not_compilable("infinite loop");
  3236         return true;            // Found unvisited kid; must be unreach
  3240   // If original bytecodes contained a mixture of floats and doubles
  3241   // check if the optimizer has made it homogenous, item (3).
  3242   if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
  3243       frc.get_float_count() > 32 &&
  3244       frc.get_double_count() == 0 &&
  3245       (10 * frc.get_call_count() < frc.get_float_count()) ) {
  3246     set_24_bit_selection_and_mode( false,  true );
  3249   set_java_calls(frc.get_java_call_count());
  3250   set_inner_loops(frc.get_inner_loop_count());
  3252   // No infinite loops, no reason to bail out.
  3253   return false;
  3256 //-----------------------------too_many_traps----------------------------------
  3257 // Report if there are too many traps at the current method and bci.
  3258 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
  3259 bool Compile::too_many_traps(ciMethod* method,
  3260                              int bci,
  3261                              Deoptimization::DeoptReason reason) {
  3262   ciMethodData* md = method->method_data();
  3263   if (md->is_empty()) {
  3264     // Assume the trap has not occurred, or that it occurred only
  3265     // because of a transient condition during start-up in the interpreter.
  3266     return false;
  3268   if (md->has_trap_at(bci, reason) != 0) {
  3269     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
  3270     // Also, if there are multiple reasons, or if there is no per-BCI record,
  3271     // assume the worst.
  3272     if (log())
  3273       log()->elem("observe trap='%s' count='%d'",
  3274                   Deoptimization::trap_reason_name(reason),
  3275                   md->trap_count(reason));
  3276     return true;
  3277   } else {
  3278     // Ignore method/bci and see if there have been too many globally.
  3279     return too_many_traps(reason, md);
  3283 // Less-accurate variant which does not require a method and bci.
  3284 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
  3285                              ciMethodData* logmd) {
  3286  if (trap_count(reason) >= (uint)PerMethodTrapLimit) {
  3287     // Too many traps globally.
  3288     // Note that we use cumulative trap_count, not just md->trap_count.
  3289     if (log()) {
  3290       int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
  3291       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
  3292                   Deoptimization::trap_reason_name(reason),
  3293                   mcount, trap_count(reason));
  3295     return true;
  3296   } else {
  3297     // The coast is clear.
  3298     return false;
  3302 //--------------------------too_many_recompiles--------------------------------
  3303 // Report if there are too many recompiles at the current method and bci.
  3304 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
  3305 // Is not eager to return true, since this will cause the compiler to use
  3306 // Action_none for a trap point, to avoid too many recompilations.
  3307 bool Compile::too_many_recompiles(ciMethod* method,
  3308                                   int bci,
  3309                                   Deoptimization::DeoptReason reason) {
  3310   ciMethodData* md = method->method_data();
  3311   if (md->is_empty()) {
  3312     // Assume the trap has not occurred, or that it occurred only
  3313     // because of a transient condition during start-up in the interpreter.
  3314     return false;
  3316   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
  3317   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
  3318   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
  3319   Deoptimization::DeoptReason per_bc_reason
  3320     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
  3321   if ((per_bc_reason == Deoptimization::Reason_none
  3322        || md->has_trap_at(bci, reason) != 0)
  3323       // The trap frequency measure we care about is the recompile count:
  3324       && md->trap_recompiled_at(bci)
  3325       && md->overflow_recompile_count() >= bc_cutoff) {
  3326     // Do not emit a trap here if it has already caused recompilations.
  3327     // Also, if there are multiple reasons, or if there is no per-BCI record,
  3328     // assume the worst.
  3329     if (log())
  3330       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
  3331                   Deoptimization::trap_reason_name(reason),
  3332                   md->trap_count(reason),
  3333                   md->overflow_recompile_count());
  3334     return true;
  3335   } else if (trap_count(reason) != 0
  3336              && decompile_count() >= m_cutoff) {
  3337     // Too many recompiles globally, and we have seen this sort of trap.
  3338     // Use cumulative decompile_count, not just md->decompile_count.
  3339     if (log())
  3340       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
  3341                   Deoptimization::trap_reason_name(reason),
  3342                   md->trap_count(reason), trap_count(reason),
  3343                   md->decompile_count(), decompile_count());
  3344     return true;
  3345   } else {
  3346     // The coast is clear.
  3347     return false;
  3352 #ifndef PRODUCT
  3353 //------------------------------verify_graph_edges---------------------------
  3354 // Walk the Graph and verify that there is a one-to-one correspondence
  3355 // between Use-Def edges and Def-Use edges in the graph.
  3356 void Compile::verify_graph_edges(bool no_dead_code) {
  3357   if (VerifyGraphEdges) {
  3358     ResourceArea *area = Thread::current()->resource_area();
  3359     Unique_Node_List visited(area);
  3360     // Call recursive graph walk to check edges
  3361     _root->verify_edges(visited);
  3362     if (no_dead_code) {
  3363       // Now make sure that no visited node is used by an unvisited node.
  3364       bool dead_nodes = 0;
  3365       Unique_Node_List checked(area);
  3366       while (visited.size() > 0) {
  3367         Node* n = visited.pop();
  3368         checked.push(n);
  3369         for (uint i = 0; i < n->outcnt(); i++) {
  3370           Node* use = n->raw_out(i);
  3371           if (checked.member(use))  continue;  // already checked
  3372           if (visited.member(use))  continue;  // already in the graph
  3373           if (use->is_Con())        continue;  // a dead ConNode is OK
  3374           // At this point, we have found a dead node which is DU-reachable.
  3375           if (dead_nodes++ == 0)
  3376             tty->print_cr("*** Dead nodes reachable via DU edges:");
  3377           use->dump(2);
  3378           tty->print_cr("---");
  3379           checked.push(use);  // No repeats; pretend it is now checked.
  3382       assert(dead_nodes == 0, "using nodes must be reachable from root");
  3387 // Verify GC barriers consistency
  3388 // Currently supported:
  3389 // - G1 pre-barriers (see GraphKit::g1_write_barrier_pre())
  3390 void Compile::verify_barriers() {
  3391   if (UseG1GC) {
  3392     // Verify G1 pre-barriers
  3393     const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + PtrQueue::byte_offset_of_active());
  3395     ResourceArea *area = Thread::current()->resource_area();
  3396     Unique_Node_List visited(area);
  3397     Node_List worklist(area);
  3398     // We're going to walk control flow backwards starting from the Root
  3399     worklist.push(_root);
  3400     while (worklist.size() > 0) {
  3401       Node* x = worklist.pop();
  3402       if (x == NULL || x == top()) continue;
  3403       if (visited.member(x)) {
  3404         continue;
  3405       } else {
  3406         visited.push(x);
  3409       if (x->is_Region()) {
  3410         for (uint i = 1; i < x->req(); i++) {
  3411           worklist.push(x->in(i));
  3413       } else {
  3414         worklist.push(x->in(0));
  3415         // We are looking for the pattern:
  3416         //                            /->ThreadLocal
  3417         // If->Bool->CmpI->LoadB->AddP->ConL(marking_offset)
  3418         //              \->ConI(0)
  3419         // We want to verify that the If and the LoadB have the same control
  3420         // See GraphKit::g1_write_barrier_pre()
  3421         if (x->is_If()) {
  3422           IfNode *iff = x->as_If();
  3423           if (iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) {
  3424             CmpNode *cmp = iff->in(1)->in(1)->as_Cmp();
  3425             if (cmp->Opcode() == Op_CmpI && cmp->in(2)->is_Con() && cmp->in(2)->bottom_type()->is_int()->get_con() == 0
  3426                 && cmp->in(1)->is_Load()) {
  3427               LoadNode* load = cmp->in(1)->as_Load();
  3428               if (load->Opcode() == Op_LoadB && load->in(2)->is_AddP() && load->in(2)->in(2)->Opcode() == Op_ThreadLocal
  3429                   && load->in(2)->in(3)->is_Con()
  3430                   && load->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == marking_offset) {
  3432                 Node* if_ctrl = iff->in(0);
  3433                 Node* load_ctrl = load->in(0);
  3435                 if (if_ctrl != load_ctrl) {
  3436                   // Skip possible CProj->NeverBranch in infinite loops
  3437                   if ((if_ctrl->is_Proj() && if_ctrl->Opcode() == Op_CProj)
  3438                       && (if_ctrl->in(0)->is_MultiBranch() && if_ctrl->in(0)->Opcode() == Op_NeverBranch)) {
  3439                     if_ctrl = if_ctrl->in(0)->in(0);
  3442                 assert(load_ctrl != NULL && if_ctrl == load_ctrl, "controls must match");
  3452 #endif
  3454 // The Compile object keeps track of failure reasons separately from the ciEnv.
  3455 // This is required because there is not quite a 1-1 relation between the
  3456 // ciEnv and its compilation task and the Compile object.  Note that one
  3457 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
  3458 // to backtrack and retry without subsuming loads.  Other than this backtracking
  3459 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
  3460 // by the logic in C2Compiler.
  3461 void Compile::record_failure(const char* reason) {
  3462   if (log() != NULL) {
  3463     log()->elem("failure reason='%s' phase='compile'", reason);
  3465   if (_failure_reason == NULL) {
  3466     // Record the first failure reason.
  3467     _failure_reason = reason;
  3470   EventCompilerFailure event;
  3471   if (event.should_commit()) {
  3472     event.set_compileID(Compile::compile_id());
  3473     event.set_failure(reason);
  3474     event.commit();
  3477   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
  3478     C->print_method(PHASE_FAILURE);
  3480   _root = NULL;  // flush the graph, too
  3483 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator, bool dolog)
  3484   : TraceTime(NULL, accumulator, false NOT_PRODUCT( || TimeCompiler ), false),
  3485     _phase_name(name), _dolog(dolog)
  3487   if (dolog) {
  3488     C = Compile::current();
  3489     _log = C->log();
  3490   } else {
  3491     C = NULL;
  3492     _log = NULL;
  3494   if (_log != NULL) {
  3495     _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
  3496     _log->stamp();
  3497     _log->end_head();
  3501 Compile::TracePhase::~TracePhase() {
  3503   C = Compile::current();
  3504   if (_dolog) {
  3505     _log = C->log();
  3506   } else {
  3507     _log = NULL;
  3510 #ifdef ASSERT
  3511   if (PrintIdealNodeCount) {
  3512     tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
  3513                   _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
  3516   if (VerifyIdealNodeCount) {
  3517     Compile::current()->print_missing_nodes();
  3519 #endif
  3521   if (_log != NULL) {
  3522     _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
  3526 //=============================================================================
  3527 // Two Constant's are equal when the type and the value are equal.
  3528 bool Compile::Constant::operator==(const Constant& other) {
  3529   if (type()          != other.type()         )  return false;
  3530   if (can_be_reused() != other.can_be_reused())  return false;
  3531   // For floating point values we compare the bit pattern.
  3532   switch (type()) {
  3533   case T_FLOAT:   return (_v._value.i == other._v._value.i);
  3534   case T_LONG:
  3535   case T_DOUBLE:  return (_v._value.j == other._v._value.j);
  3536   case T_OBJECT:
  3537   case T_ADDRESS: return (_v._value.l == other._v._value.l);
  3538   case T_VOID:    return (_v._value.l == other._v._value.l);  // jump-table entries
  3539   case T_METADATA: return (_v._metadata == other._v._metadata);
  3540   default: ShouldNotReachHere();
  3542   return false;
  3545 static int type_to_size_in_bytes(BasicType t) {
  3546   switch (t) {
  3547   case T_LONG:    return sizeof(jlong  );
  3548   case T_FLOAT:   return sizeof(jfloat );
  3549   case T_DOUBLE:  return sizeof(jdouble);
  3550   case T_METADATA: return sizeof(Metadata*);
  3551     // We use T_VOID as marker for jump-table entries (labels) which
  3552     // need an internal word relocation.
  3553   case T_VOID:
  3554   case T_ADDRESS:
  3555   case T_OBJECT:  return sizeof(jobject);
  3558   ShouldNotReachHere();
  3559   return -1;
  3562 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
  3563   // sort descending
  3564   if (a->freq() > b->freq())  return -1;
  3565   if (a->freq() < b->freq())  return  1;
  3566   return 0;
  3569 void Compile::ConstantTable::calculate_offsets_and_size() {
  3570   // First, sort the array by frequencies.
  3571   _constants.sort(qsort_comparator);
  3573 #ifdef ASSERT
  3574   // Make sure all jump-table entries were sorted to the end of the
  3575   // array (they have a negative frequency).
  3576   bool found_void = false;
  3577   for (int i = 0; i < _constants.length(); i++) {
  3578     Constant con = _constants.at(i);
  3579     if (con.type() == T_VOID)
  3580       found_void = true;  // jump-tables
  3581     else
  3582       assert(!found_void, "wrong sorting");
  3584 #endif
  3586   int offset = 0;
  3587   for (int i = 0; i < _constants.length(); i++) {
  3588     Constant* con = _constants.adr_at(i);
  3590     // Align offset for type.
  3591     int typesize = type_to_size_in_bytes(con->type());
  3592     offset = align_size_up(offset, typesize);
  3593     con->set_offset(offset);   // set constant's offset
  3595     if (con->type() == T_VOID) {
  3596       MachConstantNode* n = (MachConstantNode*) con->get_jobject();
  3597       offset = offset + typesize * n->outcnt();  // expand jump-table
  3598     } else {
  3599       offset = offset + typesize;
  3603   // Align size up to the next section start (which is insts; see
  3604   // CodeBuffer::align_at_start).
  3605   assert(_size == -1, "already set?");
  3606   _size = align_size_up(offset, CodeEntryAlignment);
  3609 void Compile::ConstantTable::emit(CodeBuffer& cb) {
  3610   MacroAssembler _masm(&cb);
  3611   for (int i = 0; i < _constants.length(); i++) {
  3612     Constant con = _constants.at(i);
  3613     address constant_addr;
  3614     switch (con.type()) {
  3615     case T_LONG:   constant_addr = _masm.long_constant(  con.get_jlong()  ); break;
  3616     case T_FLOAT:  constant_addr = _masm.float_constant( con.get_jfloat() ); break;
  3617     case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
  3618     case T_OBJECT: {
  3619       jobject obj = con.get_jobject();
  3620       int oop_index = _masm.oop_recorder()->find_index(obj);
  3621       constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
  3622       break;
  3624     case T_ADDRESS: {
  3625       address addr = (address) con.get_jobject();
  3626       constant_addr = _masm.address_constant(addr);
  3627       break;
  3629     // We use T_VOID as marker for jump-table entries (labels) which
  3630     // need an internal word relocation.
  3631     case T_VOID: {
  3632       MachConstantNode* n = (MachConstantNode*) con.get_jobject();
  3633       // Fill the jump-table with a dummy word.  The real value is
  3634       // filled in later in fill_jump_table.
  3635       address dummy = (address) n;
  3636       constant_addr = _masm.address_constant(dummy);
  3637       // Expand jump-table
  3638       for (uint i = 1; i < n->outcnt(); i++) {
  3639         address temp_addr = _masm.address_constant(dummy + i);
  3640         assert(temp_addr, "consts section too small");
  3642       break;
  3644     case T_METADATA: {
  3645       Metadata* obj = con.get_metadata();
  3646       int metadata_index = _masm.oop_recorder()->find_index(obj);
  3647       constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
  3648       break;
  3650     default: ShouldNotReachHere();
  3652     assert(constant_addr, "consts section too small");
  3653     assert((constant_addr - _masm.code()->consts()->start()) == con.offset(), err_msg_res("must be: %d == %d", constant_addr - _masm.code()->consts()->start(), con.offset()));
  3657 int Compile::ConstantTable::find_offset(Constant& con) const {
  3658   int idx = _constants.find(con);
  3659   assert(idx != -1, "constant must be in constant table");
  3660   int offset = _constants.at(idx).offset();
  3661   assert(offset != -1, "constant table not emitted yet?");
  3662   return offset;
  3665 void Compile::ConstantTable::add(Constant& con) {
  3666   if (con.can_be_reused()) {
  3667     int idx = _constants.find(con);
  3668     if (idx != -1 && _constants.at(idx).can_be_reused()) {
  3669       _constants.adr_at(idx)->inc_freq(con.freq());  // increase the frequency by the current value
  3670       return;
  3673   (void) _constants.append(con);
  3676 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
  3677   Block* b = Compile::current()->cfg()->get_block_for_node(n);
  3678   Constant con(type, value, b->_freq);
  3679   add(con);
  3680   return con;
  3683 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
  3684   Constant con(metadata);
  3685   add(con);
  3686   return con;
  3689 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
  3690   jvalue value;
  3691   BasicType type = oper->type()->basic_type();
  3692   switch (type) {
  3693   case T_LONG:    value.j = oper->constantL(); break;
  3694   case T_FLOAT:   value.f = oper->constantF(); break;
  3695   case T_DOUBLE:  value.d = oper->constantD(); break;
  3696   case T_OBJECT:
  3697   case T_ADDRESS: value.l = (jobject) oper->constant(); break;
  3698   case T_METADATA: return add((Metadata*)oper->constant()); break;
  3699   default: guarantee(false, err_msg_res("unhandled type: %s", type2name(type)));
  3701   return add(n, type, value);
  3704 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
  3705   jvalue value;
  3706   // We can use the node pointer here to identify the right jump-table
  3707   // as this method is called from Compile::Fill_buffer right before
  3708   // the MachNodes are emitted and the jump-table is filled (means the
  3709   // MachNode pointers do not change anymore).
  3710   value.l = (jobject) n;
  3711   Constant con(T_VOID, value, next_jump_table_freq(), false);  // Labels of a jump-table cannot be reused.
  3712   add(con);
  3713   return con;
  3716 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
  3717   // If called from Compile::scratch_emit_size do nothing.
  3718   if (Compile::current()->in_scratch_emit_size())  return;
  3720   assert(labels.is_nonempty(), "must be");
  3721   assert((uint) labels.length() == n->outcnt(), err_msg_res("must be equal: %d == %d", labels.length(), n->outcnt()));
  3723   // Since MachConstantNode::constant_offset() also contains
  3724   // table_base_offset() we need to subtract the table_base_offset()
  3725   // to get the plain offset into the constant table.
  3726   int offset = n->constant_offset() - table_base_offset();
  3728   MacroAssembler _masm(&cb);
  3729   address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
  3731   for (uint i = 0; i < n->outcnt(); i++) {
  3732     address* constant_addr = &jump_table_base[i];
  3733     assert(*constant_addr == (((address) n) + i), err_msg_res("all jump-table entries must contain adjusted node pointer: " INTPTR_FORMAT " == " INTPTR_FORMAT, *constant_addr, (((address) n) + i)));
  3734     *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
  3735     cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
  3739 void Compile::dump_inlining() {
  3740   if (print_inlining() || print_intrinsics()) {
  3741     // Print inlining message for candidates that we couldn't inline
  3742     // for lack of space or non constant receiver
  3743     for (int i = 0; i < _late_inlines.length(); i++) {
  3744       CallGenerator* cg = _late_inlines.at(i);
  3745       cg->print_inlining_late("live nodes > LiveNodeCountInliningCutoff");
  3747     Unique_Node_List useful;
  3748     useful.push(root());
  3749     for (uint next = 0; next < useful.size(); ++next) {
  3750       Node* n  = useful.at(next);
  3751       if (n->is_Call() && n->as_Call()->generator() != NULL && n->as_Call()->generator()->call_node() == n) {
  3752         CallNode* call = n->as_Call();
  3753         CallGenerator* cg = call->generator();
  3754         cg->print_inlining_late("receiver not constant");
  3756       uint max = n->len();
  3757       for ( uint i = 0; i < max; ++i ) {
  3758         Node *m = n->in(i);
  3759         if ( m == NULL ) continue;
  3760         useful.push(m);
  3763     for (int i = 0; i < _print_inlining_list->length(); i++) {
  3764       tty->print(_print_inlining_list->adr_at(i)->ss()->as_string());
  3769 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
  3770   if (n1->Opcode() < n2->Opcode())      return -1;
  3771   else if (n1->Opcode() > n2->Opcode()) return 1;
  3773   assert(n1->req() == n2->req(), err_msg_res("can't compare %s nodes: n1->req() = %d, n2->req() = %d", NodeClassNames[n1->Opcode()], n1->req(), n2->req()));
  3774   for (uint i = 1; i < n1->req(); i++) {
  3775     if (n1->in(i) < n2->in(i))      return -1;
  3776     else if (n1->in(i) > n2->in(i)) return 1;
  3779   return 0;
  3782 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
  3783   Node* n1 = *n1p;
  3784   Node* n2 = *n2p;
  3786   return cmp_expensive_nodes(n1, n2);
  3789 void Compile::sort_expensive_nodes() {
  3790   if (!expensive_nodes_sorted()) {
  3791     _expensive_nodes->sort(cmp_expensive_nodes);
  3795 bool Compile::expensive_nodes_sorted() const {
  3796   for (int i = 1; i < _expensive_nodes->length(); i++) {
  3797     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
  3798       return false;
  3801   return true;
  3804 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
  3805   if (_expensive_nodes->length() == 0) {
  3806     return false;
  3809   assert(OptimizeExpensiveOps, "optimization off?");
  3811   // Take this opportunity to remove dead nodes from the list
  3812   int j = 0;
  3813   for (int i = 0; i < _expensive_nodes->length(); i++) {
  3814     Node* n = _expensive_nodes->at(i);
  3815     if (!n->is_unreachable(igvn)) {
  3816       assert(n->is_expensive(), "should be expensive");
  3817       _expensive_nodes->at_put(j, n);
  3818       j++;
  3821   _expensive_nodes->trunc_to(j);
  3823   // Then sort the list so that similar nodes are next to each other
  3824   // and check for at least two nodes of identical kind with same data
  3825   // inputs.
  3826   sort_expensive_nodes();
  3828   for (int i = 0; i < _expensive_nodes->length()-1; i++) {
  3829     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
  3830       return true;
  3834   return false;
  3837 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
  3838   if (_expensive_nodes->length() == 0) {
  3839     return;
  3842   assert(OptimizeExpensiveOps, "optimization off?");
  3844   // Sort to bring similar nodes next to each other and clear the
  3845   // control input of nodes for which there's only a single copy.
  3846   sort_expensive_nodes();
  3848   int j = 0;
  3849   int identical = 0;
  3850   int i = 0;
  3851   for (; i < _expensive_nodes->length()-1; i++) {
  3852     assert(j <= i, "can't write beyond current index");
  3853     if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
  3854       identical++;
  3855       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3856       continue;
  3858     if (identical > 0) {
  3859       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3860       identical = 0;
  3861     } else {
  3862       Node* n = _expensive_nodes->at(i);
  3863       igvn.hash_delete(n);
  3864       n->set_req(0, NULL);
  3865       igvn.hash_insert(n);
  3868   if (identical > 0) {
  3869     _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3870   } else if (_expensive_nodes->length() >= 1) {
  3871     Node* n = _expensive_nodes->at(i);
  3872     igvn.hash_delete(n);
  3873     n->set_req(0, NULL);
  3874     igvn.hash_insert(n);
  3876   _expensive_nodes->trunc_to(j);
  3879 void Compile::add_expensive_node(Node * n) {
  3880   assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
  3881   assert(n->is_expensive(), "expensive nodes with non-null control here only");
  3882   assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
  3883   if (OptimizeExpensiveOps) {
  3884     _expensive_nodes->append(n);
  3885   } else {
  3886     // Clear control input and let IGVN optimize expensive nodes if
  3887     // OptimizeExpensiveOps is off.
  3888     n->set_req(0, NULL);
  3892 /**
  3893  * Remove the speculative part of types and clean up the graph
  3894  */
  3895 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
  3896   if (UseTypeSpeculation) {
  3897     Unique_Node_List worklist;
  3898     worklist.push(root());
  3899     int modified = 0;
  3900     // Go over all type nodes that carry a speculative type, drop the
  3901     // speculative part of the type and enqueue the node for an igvn
  3902     // which may optimize it out.
  3903     for (uint next = 0; next < worklist.size(); ++next) {
  3904       Node *n  = worklist.at(next);
  3905       if (n->is_Type() && n->as_Type()->type()->isa_oopptr() != NULL &&
  3906           n->as_Type()->type()->is_oopptr()->speculative() != NULL) {
  3907         TypeNode* tn = n->as_Type();
  3908         const TypeOopPtr* t = tn->type()->is_oopptr();
  3909         bool in_hash = igvn.hash_delete(n);
  3910         assert(in_hash, "node should be in igvn hash table");
  3911         tn->set_type(t->remove_speculative());
  3912         igvn.hash_insert(n);
  3913         igvn._worklist.push(n); // give it a chance to go away
  3914         modified++;
  3916       uint max = n->len();
  3917       for( uint i = 0; i < max; ++i ) {
  3918         Node *m = n->in(i);
  3919         if (not_a_node(m))  continue;
  3920         worklist.push(m);
  3923     // Drop the speculative part of all types in the igvn's type table
  3924     igvn.remove_speculative_types();
  3925     if (modified > 0) {
  3926       igvn.optimize();
  3931 // Auxiliary method to support randomized stressing/fuzzing.
  3932 //
  3933 // This method can be called the arbitrary number of times, with current count
  3934 // as the argument. The logic allows selecting a single candidate from the
  3935 // running list of candidates as follows:
  3936 //    int count = 0;
  3937 //    Cand* selected = null;
  3938 //    while(cand = cand->next()) {
  3939 //      if (randomized_select(++count)) {
  3940 //        selected = cand;
  3941 //      }
  3942 //    }
  3943 //
  3944 // Including count equalizes the chances any candidate is "selected".
  3945 // This is useful when we don't have the complete list of candidates to choose
  3946 // from uniformly. In this case, we need to adjust the randomicity of the
  3947 // selection, or else we will end up biasing the selection towards the latter
  3948 // candidates.
  3949 //
  3950 // Quick back-envelope calculation shows that for the list of n candidates
  3951 // the equal probability for the candidate to persist as "best" can be
  3952 // achieved by replacing it with "next" k-th candidate with the probability
  3953 // of 1/k. It can be easily shown that by the end of the run, the
  3954 // probability for any candidate is converged to 1/n, thus giving the
  3955 // uniform distribution among all the candidates.
  3956 //
  3957 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
  3958 #define RANDOMIZED_DOMAIN_POW 29
  3959 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
  3960 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
  3961 bool Compile::randomized_select(int count) {
  3962   assert(count > 0, "only positive");
  3963   return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);

mercurial