src/share/vm/opto/compile.cpp

Tue, 08 Oct 2013 17:35:51 +0200

author
mgerdin
date
Tue, 08 Oct 2013 17:35:51 +0200
changeset 5860
69944b868a32
parent 5763
1b64d46620a3
child 5927
4a2acfb16e97
permissions
-rw-r--r--

8014555: G1: Memory ordering problem with Conc refinement and card marking
Summary: Add a StoreLoad barrier in the G1 post-barrier to fix a race with concurrent refinement. Also-reviewed-by: martin.doerr@sap.com
Reviewed-by: iveresov, tschatzl, brutisso, roland, kvn

     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/memnode.hpp"
    51 #include "opto/mulnode.hpp"
    52 #include "opto/node.hpp"
    53 #include "opto/opcodes.hpp"
    54 #include "opto/output.hpp"
    55 #include "opto/parse.hpp"
    56 #include "opto/phaseX.hpp"
    57 #include "opto/rootnode.hpp"
    58 #include "opto/runtime.hpp"
    59 #include "opto/stringopts.hpp"
    60 #include "opto/type.hpp"
    61 #include "opto/vectornode.hpp"
    62 #include "runtime/arguments.hpp"
    63 #include "runtime/signature.hpp"
    64 #include "runtime/stubRoutines.hpp"
    65 #include "runtime/timer.hpp"
    66 #include "trace/tracing.hpp"
    67 #include "utilities/copy.hpp"
    68 #ifdef TARGET_ARCH_MODEL_x86_32
    69 # include "adfiles/ad_x86_32.hpp"
    70 #endif
    71 #ifdef TARGET_ARCH_MODEL_x86_64
    72 # include "adfiles/ad_x86_64.hpp"
    73 #endif
    74 #ifdef TARGET_ARCH_MODEL_sparc
    75 # include "adfiles/ad_sparc.hpp"
    76 #endif
    77 #ifdef TARGET_ARCH_MODEL_zero
    78 # include "adfiles/ad_zero.hpp"
    79 #endif
    80 #ifdef TARGET_ARCH_MODEL_arm
    81 # include "adfiles/ad_arm.hpp"
    82 #endif
    83 #ifdef TARGET_ARCH_MODEL_ppc
    84 # include "adfiles/ad_ppc.hpp"
    85 #endif
    88 // -------------------- Compile::mach_constant_base_node -----------------------
    89 // Constant table base node singleton.
    90 MachConstantBaseNode* Compile::mach_constant_base_node() {
    91   if (_mach_constant_base_node == NULL) {
    92     _mach_constant_base_node = new (C) MachConstantBaseNode();
    93     _mach_constant_base_node->add_req(C->root());
    94   }
    95   return _mach_constant_base_node;
    96 }
    99 /// Support for intrinsics.
   101 // Return the index at which m must be inserted (or already exists).
   102 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
   103 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual) {
   104 #ifdef ASSERT
   105   for (int i = 1; i < _intrinsics->length(); i++) {
   106     CallGenerator* cg1 = _intrinsics->at(i-1);
   107     CallGenerator* cg2 = _intrinsics->at(i);
   108     assert(cg1->method() != cg2->method()
   109            ? cg1->method()     < cg2->method()
   110            : cg1->is_virtual() < cg2->is_virtual(),
   111            "compiler intrinsics list must stay sorted");
   112   }
   113 #endif
   114   // Binary search sorted list, in decreasing intervals [lo, hi].
   115   int lo = 0, hi = _intrinsics->length()-1;
   116   while (lo <= hi) {
   117     int mid = (uint)(hi + lo) / 2;
   118     ciMethod* mid_m = _intrinsics->at(mid)->method();
   119     if (m < mid_m) {
   120       hi = mid-1;
   121     } else if (m > mid_m) {
   122       lo = mid+1;
   123     } else {
   124       // look at minor sort key
   125       bool mid_virt = _intrinsics->at(mid)->is_virtual();
   126       if (is_virtual < mid_virt) {
   127         hi = mid-1;
   128       } else if (is_virtual > mid_virt) {
   129         lo = mid+1;
   130       } else {
   131         return mid;  // exact match
   132       }
   133     }
   134   }
   135   return lo;  // inexact match
   136 }
   138 void Compile::register_intrinsic(CallGenerator* cg) {
   139   if (_intrinsics == NULL) {
   140     _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
   141   }
   142   // This code is stolen from ciObjectFactory::insert.
   143   // Really, GrowableArray should have methods for
   144   // insert_at, remove_at, and binary_search.
   145   int len = _intrinsics->length();
   146   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual());
   147   if (index == len) {
   148     _intrinsics->append(cg);
   149   } else {
   150 #ifdef ASSERT
   151     CallGenerator* oldcg = _intrinsics->at(index);
   152     assert(oldcg->method() != cg->method() || oldcg->is_virtual() != cg->is_virtual(), "don't register twice");
   153 #endif
   154     _intrinsics->append(_intrinsics->at(len-1));
   155     int pos;
   156     for (pos = len-2; pos >= index; pos--) {
   157       _intrinsics->at_put(pos+1,_intrinsics->at(pos));
   158     }
   159     _intrinsics->at_put(index, cg);
   160   }
   161   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
   162 }
   164 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
   165   assert(m->is_loaded(), "don't try this on unloaded methods");
   166   if (_intrinsics != NULL) {
   167     int index = intrinsic_insertion_index(m, is_virtual);
   168     if (index < _intrinsics->length()
   169         && _intrinsics->at(index)->method() == m
   170         && _intrinsics->at(index)->is_virtual() == is_virtual) {
   171       return _intrinsics->at(index);
   172     }
   173   }
   174   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
   175   if (m->intrinsic_id() != vmIntrinsics::_none &&
   176       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
   177     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
   178     if (cg != NULL) {
   179       // Save it for next time:
   180       register_intrinsic(cg);
   181       return cg;
   182     } else {
   183       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
   184     }
   185   }
   186   return NULL;
   187 }
   189 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
   190 // in library_call.cpp.
   193 #ifndef PRODUCT
   194 // statistics gathering...
   196 juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
   197 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
   199 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
   200   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
   201   int oflags = _intrinsic_hist_flags[id];
   202   assert(flags != 0, "what happened?");
   203   if (is_virtual) {
   204     flags |= _intrinsic_virtual;
   205   }
   206   bool changed = (flags != oflags);
   207   if ((flags & _intrinsic_worked) != 0) {
   208     juint count = (_intrinsic_hist_count[id] += 1);
   209     if (count == 1) {
   210       changed = true;           // first time
   211     }
   212     // increment the overall count also:
   213     _intrinsic_hist_count[vmIntrinsics::_none] += 1;
   214   }
   215   if (changed) {
   216     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
   217       // Something changed about the intrinsic's virtuality.
   218       if ((flags & _intrinsic_virtual) != 0) {
   219         // This is the first use of this intrinsic as a virtual call.
   220         if (oflags != 0) {
   221           // We already saw it as a non-virtual, so note both cases.
   222           flags |= _intrinsic_both;
   223         }
   224       } else if ((oflags & _intrinsic_both) == 0) {
   225         // This is the first use of this intrinsic as a non-virtual
   226         flags |= _intrinsic_both;
   227       }
   228     }
   229     _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
   230   }
   231   // update the overall flags also:
   232   _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
   233   return changed;
   234 }
   236 static char* format_flags(int flags, char* buf) {
   237   buf[0] = 0;
   238   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
   239   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
   240   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
   241   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
   242   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
   243   if (buf[0] == 0)  strcat(buf, ",");
   244   assert(buf[0] == ',', "must be");
   245   return &buf[1];
   246 }
   248 void Compile::print_intrinsic_statistics() {
   249   char flagsbuf[100];
   250   ttyLocker ttyl;
   251   if (xtty != NULL)  xtty->head("statistics type='intrinsic'");
   252   tty->print_cr("Compiler intrinsic usage:");
   253   juint total = _intrinsic_hist_count[vmIntrinsics::_none];
   254   if (total == 0)  total = 1;  // avoid div0 in case of no successes
   255   #define PRINT_STAT_LINE(name, c, f) \
   256     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
   257   for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
   258     vmIntrinsics::ID id = (vmIntrinsics::ID) index;
   259     int   flags = _intrinsic_hist_flags[id];
   260     juint count = _intrinsic_hist_count[id];
   261     if ((flags | count) != 0) {
   262       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
   263     }
   264   }
   265   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
   266   if (xtty != NULL)  xtty->tail("statistics");
   267 }
   269 void Compile::print_statistics() {
   270   { ttyLocker ttyl;
   271     if (xtty != NULL)  xtty->head("statistics type='opto'");
   272     Parse::print_statistics();
   273     PhaseCCP::print_statistics();
   274     PhaseRegAlloc::print_statistics();
   275     Scheduling::print_statistics();
   276     PhasePeephole::print_statistics();
   277     PhaseIdealLoop::print_statistics();
   278     if (xtty != NULL)  xtty->tail("statistics");
   279   }
   280   if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
   281     // put this under its own <statistics> element.
   282     print_intrinsic_statistics();
   283   }
   284 }
   285 #endif //PRODUCT
   287 // Support for bundling info
   288 Bundle* Compile::node_bundling(const Node *n) {
   289   assert(valid_bundle_info(n), "oob");
   290   return &_node_bundling_base[n->_idx];
   291 }
   293 bool Compile::valid_bundle_info(const Node *n) {
   294   return (_node_bundling_limit > n->_idx);
   295 }
   298 void Compile::gvn_replace_by(Node* n, Node* nn) {
   299   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
   300     Node* use = n->last_out(i);
   301     bool is_in_table = initial_gvn()->hash_delete(use);
   302     uint uses_found = 0;
   303     for (uint j = 0; j < use->len(); j++) {
   304       if (use->in(j) == n) {
   305         if (j < use->req())
   306           use->set_req(j, nn);
   307         else
   308           use->set_prec(j, nn);
   309         uses_found++;
   310       }
   311     }
   312     if (is_in_table) {
   313       // reinsert into table
   314       initial_gvn()->hash_find_insert(use);
   315     }
   316     record_for_igvn(use);
   317     i -= uses_found;    // we deleted 1 or more copies of this edge
   318   }
   319 }
   322 static inline bool not_a_node(const Node* n) {
   323   if (n == NULL)                   return true;
   324   if (((intptr_t)n & 1) != 0)      return true;  // uninitialized, etc.
   325   if (*(address*)n == badAddress)  return true;  // kill by Node::destruct
   326   return false;
   327 }
   329 // Identify all nodes that are reachable from below, useful.
   330 // Use breadth-first pass that records state in a Unique_Node_List,
   331 // recursive traversal is slower.
   332 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
   333   int estimated_worklist_size = unique();
   334   useful.map( estimated_worklist_size, NULL );  // preallocate space
   336   // Initialize worklist
   337   if (root() != NULL)     { useful.push(root()); }
   338   // If 'top' is cached, declare it useful to preserve cached node
   339   if( cached_top_node() ) { useful.push(cached_top_node()); }
   341   // Push all useful nodes onto the list, breadthfirst
   342   for( uint next = 0; next < useful.size(); ++next ) {
   343     assert( next < unique(), "Unique useful nodes < total nodes");
   344     Node *n  = useful.at(next);
   345     uint max = n->len();
   346     for( uint i = 0; i < max; ++i ) {
   347       Node *m = n->in(i);
   348       if (not_a_node(m))  continue;
   349       useful.push(m);
   350     }
   351   }
   352 }
   354 // Update dead_node_list with any missing dead nodes using useful
   355 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
   356 void Compile::update_dead_node_list(Unique_Node_List &useful) {
   357   uint max_idx = unique();
   358   VectorSet& useful_node_set = useful.member_set();
   360   for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
   361     // If node with index node_idx is not in useful set,
   362     // mark it as dead in dead node list.
   363     if (! useful_node_set.test(node_idx) ) {
   364       record_dead_node(node_idx);
   365     }
   366   }
   367 }
   369 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
   370   int shift = 0;
   371   for (int i = 0; i < inlines->length(); i++) {
   372     CallGenerator* cg = inlines->at(i);
   373     CallNode* call = cg->call_node();
   374     if (shift > 0) {
   375       inlines->at_put(i-shift, cg);
   376     }
   377     if (!useful.member(call)) {
   378       shift++;
   379     }
   380   }
   381   inlines->trunc_to(inlines->length()-shift);
   382 }
   384 // Disconnect all useless nodes by disconnecting those at the boundary.
   385 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
   386   uint next = 0;
   387   while (next < useful.size()) {
   388     Node *n = useful.at(next++);
   389     // Use raw traversal of out edges since this code removes out edges
   390     int max = n->outcnt();
   391     for (int j = 0; j < max; ++j) {
   392       Node* child = n->raw_out(j);
   393       if (! useful.member(child)) {
   394         assert(!child->is_top() || child != top(),
   395                "If top is cached in Compile object it is in useful list");
   396         // Only need to remove this out-edge to the useless node
   397         n->raw_del_out(j);
   398         --j;
   399         --max;
   400       }
   401     }
   402     if (n->outcnt() == 1 && n->has_special_unique_user()) {
   403       record_for_igvn(n->unique_out());
   404     }
   405   }
   406   // Remove useless macro and predicate opaq nodes
   407   for (int i = C->macro_count()-1; i >= 0; i--) {
   408     Node* n = C->macro_node(i);
   409     if (!useful.member(n)) {
   410       remove_macro_node(n);
   411     }
   412   }
   413   // Remove useless expensive node
   414   for (int i = C->expensive_count()-1; i >= 0; i--) {
   415     Node* n = C->expensive_node(i);
   416     if (!useful.member(n)) {
   417       remove_expensive_node(n);
   418     }
   419   }
   420   // clean up the late inline lists
   421   remove_useless_late_inlines(&_string_late_inlines, useful);
   422   remove_useless_late_inlines(&_boxing_late_inlines, useful);
   423   remove_useless_late_inlines(&_late_inlines, useful);
   424   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
   425 }
   427 //------------------------------frame_size_in_words-----------------------------
   428 // frame_slots in units of words
   429 int Compile::frame_size_in_words() const {
   430   // shift is 0 in LP32 and 1 in LP64
   431   const int shift = (LogBytesPerWord - LogBytesPerInt);
   432   int words = _frame_slots >> shift;
   433   assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
   434   return words;
   435 }
   437 // ============================================================================
   438 //------------------------------CompileWrapper---------------------------------
   439 class CompileWrapper : public StackObj {
   440   Compile *const _compile;
   441  public:
   442   CompileWrapper(Compile* compile);
   444   ~CompileWrapper();
   445 };
   447 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
   448   // the Compile* pointer is stored in the current ciEnv:
   449   ciEnv* env = compile->env();
   450   assert(env == ciEnv::current(), "must already be a ciEnv active");
   451   assert(env->compiler_data() == NULL, "compile already active?");
   452   env->set_compiler_data(compile);
   453   assert(compile == Compile::current(), "sanity");
   455   compile->set_type_dict(NULL);
   456   compile->set_type_hwm(NULL);
   457   compile->set_type_last_size(0);
   458   compile->set_last_tf(NULL, NULL);
   459   compile->set_indexSet_arena(NULL);
   460   compile->set_indexSet_free_block_list(NULL);
   461   compile->init_type_arena();
   462   Type::Initialize(compile);
   463   _compile->set_scratch_buffer_blob(NULL);
   464   _compile->begin_method();
   465 }
   466 CompileWrapper::~CompileWrapper() {
   467   _compile->end_method();
   468   if (_compile->scratch_buffer_blob() != NULL)
   469     BufferBlob::free(_compile->scratch_buffer_blob());
   470   _compile->env()->set_compiler_data(NULL);
   471 }
   474 //----------------------------print_compile_messages---------------------------
   475 void Compile::print_compile_messages() {
   476 #ifndef PRODUCT
   477   // Check if recompiling
   478   if (_subsume_loads == false && PrintOpto) {
   479     // Recompiling without allowing machine instructions to subsume loads
   480     tty->print_cr("*********************************************************");
   481     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
   482     tty->print_cr("*********************************************************");
   483   }
   484   if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
   485     // Recompiling without escape analysis
   486     tty->print_cr("*********************************************************");
   487     tty->print_cr("** Bailout: Recompile without escape analysis          **");
   488     tty->print_cr("*********************************************************");
   489   }
   490   if (_eliminate_boxing != EliminateAutoBox && PrintOpto) {
   491     // Recompiling without boxing elimination
   492     tty->print_cr("*********************************************************");
   493     tty->print_cr("** Bailout: Recompile without boxing elimination       **");
   494     tty->print_cr("*********************************************************");
   495   }
   496   if (env()->break_at_compile()) {
   497     // Open the debugger when compiling this method.
   498     tty->print("### Breaking when compiling: ");
   499     method()->print_short_name();
   500     tty->cr();
   501     BREAKPOINT;
   502   }
   504   if( PrintOpto ) {
   505     if (is_osr_compilation()) {
   506       tty->print("[OSR]%3d", _compile_id);
   507     } else {
   508       tty->print("%3d", _compile_id);
   509     }
   510   }
   511 #endif
   512 }
   515 //-----------------------init_scratch_buffer_blob------------------------------
   516 // Construct a temporary BufferBlob and cache it for this compile.
   517 void Compile::init_scratch_buffer_blob(int const_size) {
   518   // If there is already a scratch buffer blob allocated and the
   519   // constant section is big enough, use it.  Otherwise free the
   520   // current and allocate a new one.
   521   BufferBlob* blob = scratch_buffer_blob();
   522   if ((blob != NULL) && (const_size <= _scratch_const_size)) {
   523     // Use the current blob.
   524   } else {
   525     if (blob != NULL) {
   526       BufferBlob::free(blob);
   527     }
   529     ResourceMark rm;
   530     _scratch_const_size = const_size;
   531     int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
   532     blob = BufferBlob::create("Compile::scratch_buffer", size);
   533     // Record the buffer blob for next time.
   534     set_scratch_buffer_blob(blob);
   535     // Have we run out of code space?
   536     if (scratch_buffer_blob() == NULL) {
   537       // Let CompilerBroker disable further compilations.
   538       record_failure("Not enough space for scratch buffer in CodeCache");
   539       return;
   540     }
   541   }
   543   // Initialize the relocation buffers
   544   relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
   545   set_scratch_locs_memory(locs_buf);
   546 }
   549 //-----------------------scratch_emit_size-------------------------------------
   550 // Helper function that computes size by emitting code
   551 uint Compile::scratch_emit_size(const Node* n) {
   552   // Start scratch_emit_size section.
   553   set_in_scratch_emit_size(true);
   555   // Emit into a trash buffer and count bytes emitted.
   556   // This is a pretty expensive way to compute a size,
   557   // but it works well enough if seldom used.
   558   // All common fixed-size instructions are given a size
   559   // method by the AD file.
   560   // Note that the scratch buffer blob and locs memory are
   561   // allocated at the beginning of the compile task, and
   562   // may be shared by several calls to scratch_emit_size.
   563   // The allocation of the scratch buffer blob is particularly
   564   // expensive, since it has to grab the code cache lock.
   565   BufferBlob* blob = this->scratch_buffer_blob();
   566   assert(blob != NULL, "Initialize BufferBlob at start");
   567   assert(blob->size() > MAX_inst_size, "sanity");
   568   relocInfo* locs_buf = scratch_locs_memory();
   569   address blob_begin = blob->content_begin();
   570   address blob_end   = (address)locs_buf;
   571   assert(blob->content_contains(blob_end), "sanity");
   572   CodeBuffer buf(blob_begin, blob_end - blob_begin);
   573   buf.initialize_consts_size(_scratch_const_size);
   574   buf.initialize_stubs_size(MAX_stubs_size);
   575   assert(locs_buf != NULL, "sanity");
   576   int lsize = MAX_locs_size / 3;
   577   buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
   578   buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
   579   buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
   581   // Do the emission.
   583   Label fakeL; // Fake label for branch instructions.
   584   Label*   saveL = NULL;
   585   uint save_bnum = 0;
   586   bool is_branch = n->is_MachBranch();
   587   if (is_branch) {
   588     MacroAssembler masm(&buf);
   589     masm.bind(fakeL);
   590     n->as_MachBranch()->save_label(&saveL, &save_bnum);
   591     n->as_MachBranch()->label_set(&fakeL, 0);
   592   }
   593   n->emit(buf, this->regalloc());
   594   if (is_branch) // Restore label.
   595     n->as_MachBranch()->label_set(saveL, save_bnum);
   597   // End scratch_emit_size section.
   598   set_in_scratch_emit_size(false);
   600   return buf.insts_size();
   601 }
   604 // ============================================================================
   605 //------------------------------Compile standard-------------------------------
   606 debug_only( int Compile::_debug_idx = 100000; )
   608 // Compile a method.  entry_bci is -1 for normal compilations and indicates
   609 // the continuation bci for on stack replacement.
   612 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci,
   613                   bool subsume_loads, bool do_escape_analysis, bool eliminate_boxing )
   614                 : Phase(Compiler),
   615                   _env(ci_env),
   616                   _log(ci_env->log()),
   617                   _compile_id(ci_env->compile_id()),
   618                   _save_argument_registers(false),
   619                   _stub_name(NULL),
   620                   _stub_function(NULL),
   621                   _stub_entry_point(NULL),
   622                   _method(target),
   623                   _entry_bci(osr_bci),
   624                   _initial_gvn(NULL),
   625                   _for_igvn(NULL),
   626                   _warm_calls(NULL),
   627                   _subsume_loads(subsume_loads),
   628                   _do_escape_analysis(do_escape_analysis),
   629                   _eliminate_boxing(eliminate_boxing),
   630                   _failure_reason(NULL),
   631                   _code_buffer("Compile::Fill_buffer"),
   632                   _orig_pc_slot(0),
   633                   _orig_pc_slot_offset_in_bytes(0),
   634                   _has_method_handle_invokes(false),
   635                   _mach_constant_base_node(NULL),
   636                   _node_bundling_limit(0),
   637                   _node_bundling_base(NULL),
   638                   _java_calls(0),
   639                   _inner_loops(0),
   640                   _scratch_const_size(-1),
   641                   _in_scratch_emit_size(false),
   642                   _dead_node_list(comp_arena()),
   643                   _dead_node_count(0),
   644 #ifndef PRODUCT
   645                   _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
   646                   _printer(IdealGraphPrinter::printer()),
   647 #endif
   648                   _congraph(NULL),
   649                   _late_inlines(comp_arena(), 2, 0, NULL),
   650                   _string_late_inlines(comp_arena(), 2, 0, NULL),
   651                   _boxing_late_inlines(comp_arena(), 2, 0, NULL),
   652                   _late_inlines_pos(0),
   653                   _number_of_mh_late_inlines(0),
   654                   _inlining_progress(false),
   655                   _inlining_incrementally(false),
   656                   _print_inlining_list(NULL),
   657                   _print_inlining_idx(0) {
   658   C = this;
   660   CompileWrapper cw(this);
   661 #ifndef PRODUCT
   662   if (TimeCompiler2) {
   663     tty->print(" ");
   664     target->holder()->name()->print();
   665     tty->print(".");
   666     target->print_short_name();
   667     tty->print("  ");
   668   }
   669   TraceTime t1("Total compilation time", &_t_totalCompilation, TimeCompiler, TimeCompiler2);
   670   TraceTime t2(NULL, &_t_methodCompilation, TimeCompiler, false);
   671   bool print_opto_assembly = PrintOptoAssembly || _method->has_option("PrintOptoAssembly");
   672   if (!print_opto_assembly) {
   673     bool print_assembly = (PrintAssembly || _method->should_print_assembly());
   674     if (print_assembly && !Disassembler::can_decode()) {
   675       tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
   676       print_opto_assembly = true;
   677     }
   678   }
   679   set_print_assembly(print_opto_assembly);
   680   set_parsed_irreducible_loop(false);
   681 #endif
   682   set_print_inlining(PrintInlining || method()->has_option("PrintInlining") NOT_PRODUCT( || PrintOptoInlining));
   683   set_print_intrinsics(PrintIntrinsics || method()->has_option("PrintIntrinsics"));
   685   if (ProfileTraps) {
   686     // Make sure the method being compiled gets its own MDO,
   687     // so we can at least track the decompile_count().
   688     method()->ensure_method_data();
   689   }
   691   Init(::AliasLevel);
   694   print_compile_messages();
   696   if (UseOldInlining || PrintCompilation NOT_PRODUCT( || PrintOpto) )
   697     _ilt = InlineTree::build_inline_tree_root();
   698   else
   699     _ilt = NULL;
   701   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
   702   assert(num_alias_types() >= AliasIdxRaw, "");
   704 #define MINIMUM_NODE_HASH  1023
   705   // Node list that Iterative GVN will start with
   706   Unique_Node_List for_igvn(comp_arena());
   707   set_for_igvn(&for_igvn);
   709   // GVN that will be run immediately on new nodes
   710   uint estimated_size = method()->code_size()*4+64;
   711   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
   712   PhaseGVN gvn(node_arena(), estimated_size);
   713   set_initial_gvn(&gvn);
   715   if (print_inlining() || print_intrinsics()) {
   716     _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
   717   }
   718   { // Scope for timing the parser
   719     TracePhase t3("parse", &_t_parser, true);
   721     // Put top into the hash table ASAP.
   722     initial_gvn()->transform_no_reclaim(top());
   724     // Set up tf(), start(), and find a CallGenerator.
   725     CallGenerator* cg = NULL;
   726     if (is_osr_compilation()) {
   727       const TypeTuple *domain = StartOSRNode::osr_domain();
   728       const TypeTuple *range = TypeTuple::make_range(method()->signature());
   729       init_tf(TypeFunc::make(domain, range));
   730       StartNode* s = new (this) StartOSRNode(root(), domain);
   731       initial_gvn()->set_type_bottom(s);
   732       init_start(s);
   733       cg = CallGenerator::for_osr(method(), entry_bci());
   734     } else {
   735       // Normal case.
   736       init_tf(TypeFunc::make(method()));
   737       StartNode* s = new (this) StartNode(root(), tf()->domain());
   738       initial_gvn()->set_type_bottom(s);
   739       init_start(s);
   740       if (method()->intrinsic_id() == vmIntrinsics::_Reference_get && UseG1GC) {
   741         // With java.lang.ref.reference.get() we must go through the
   742         // intrinsic when G1 is enabled - even when get() is the root
   743         // method of the compile - so that, if necessary, the value in
   744         // the referent field of the reference object gets recorded by
   745         // the pre-barrier code.
   746         // Specifically, if G1 is enabled, the value in the referent
   747         // field is recorded by the G1 SATB pre barrier. This will
   748         // result in the referent being marked live and the reference
   749         // object removed from the list of discovered references during
   750         // reference processing.
   751         cg = find_intrinsic(method(), false);
   752       }
   753       if (cg == NULL) {
   754         float past_uses = method()->interpreter_invocation_count();
   755         float expected_uses = past_uses;
   756         cg = CallGenerator::for_inline(method(), expected_uses);
   757       }
   758     }
   759     if (failing())  return;
   760     if (cg == NULL) {
   761       record_method_not_compilable_all_tiers("cannot parse method");
   762       return;
   763     }
   764     JVMState* jvms = build_start_state(start(), tf());
   765     if ((jvms = cg->generate(jvms)) == NULL) {
   766       record_method_not_compilable("method parse failed");
   767       return;
   768     }
   769     GraphKit kit(jvms);
   771     if (!kit.stopped()) {
   772       // Accept return values, and transfer control we know not where.
   773       // This is done by a special, unique ReturnNode bound to root.
   774       return_values(kit.jvms());
   775     }
   777     if (kit.has_exceptions()) {
   778       // Any exceptions that escape from this call must be rethrown
   779       // to whatever caller is dynamically above us on the stack.
   780       // This is done by a special, unique RethrowNode bound to root.
   781       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
   782     }
   784     assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
   786     if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
   787       inline_string_calls(true);
   788     }
   790     if (failing())  return;
   792     print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
   794     // Remove clutter produced by parsing.
   795     if (!failing()) {
   796       ResourceMark rm;
   797       PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
   798     }
   799   }
   801   // Note:  Large methods are capped off in do_one_bytecode().
   802   if (failing())  return;
   804   // After parsing, node notes are no longer automagic.
   805   // They must be propagated by register_new_node_with_optimizer(),
   806   // clone(), or the like.
   807   set_default_node_notes(NULL);
   809   for (;;) {
   810     int successes = Inline_Warm();
   811     if (failing())  return;
   812     if (successes == 0)  break;
   813   }
   815   // Drain the list.
   816   Finish_Warm();
   817 #ifndef PRODUCT
   818   if (_printer) {
   819     _printer->print_inlining(this);
   820   }
   821 #endif
   823   if (failing())  return;
   824   NOT_PRODUCT( verify_graph_edges(); )
   826   // Now optimize
   827   Optimize();
   828   if (failing())  return;
   829   NOT_PRODUCT( verify_graph_edges(); )
   831 #ifndef PRODUCT
   832   if (PrintIdeal) {
   833     ttyLocker ttyl;  // keep the following output all in one block
   834     // This output goes directly to the tty, not the compiler log.
   835     // To enable tools to match it up with the compilation activity,
   836     // be sure to tag this tty output with the compile ID.
   837     if (xtty != NULL) {
   838       xtty->head("ideal compile_id='%d'%s", compile_id(),
   839                  is_osr_compilation()    ? " compile_kind='osr'" :
   840                  "");
   841     }
   842     root()->dump(9999);
   843     if (xtty != NULL) {
   844       xtty->tail("ideal");
   845     }
   846   }
   847 #endif
   849   // Now that we know the size of all the monitors we can add a fixed slot
   850   // for the original deopt pc.
   852   _orig_pc_slot =  fixed_slots();
   853   int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
   854   set_fixed_slots(next_slot);
   856   // Now generate code
   857   Code_Gen();
   858   if (failing())  return;
   860   // Check if we want to skip execution of all compiled code.
   861   {
   862 #ifndef PRODUCT
   863     if (OptoNoExecute) {
   864       record_method_not_compilable("+OptoNoExecute");  // Flag as failed
   865       return;
   866     }
   867     TracePhase t2("install_code", &_t_registerMethod, TimeCompiler);
   868 #endif
   870     if (is_osr_compilation()) {
   871       _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
   872       _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
   873     } else {
   874       _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
   875       _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
   876     }
   878     env()->register_method(_method, _entry_bci,
   879                            &_code_offsets,
   880                            _orig_pc_slot_offset_in_bytes,
   881                            code_buffer(),
   882                            frame_size_in_words(), _oop_map_set,
   883                            &_handler_table, &_inc_table,
   884                            compiler,
   885                            env()->comp_level(),
   886                            has_unsafe_access(),
   887                            SharedRuntime::is_wide_vector(max_vector_size())
   888                            );
   890     if (log() != NULL) // Print code cache state into compiler log
   891       log()->code_cache_state();
   892   }
   893 }
   895 //------------------------------Compile----------------------------------------
   896 // Compile a runtime stub
   897 Compile::Compile( ciEnv* ci_env,
   898                   TypeFunc_generator generator,
   899                   address stub_function,
   900                   const char *stub_name,
   901                   int is_fancy_jump,
   902                   bool pass_tls,
   903                   bool save_arg_registers,
   904                   bool return_pc )
   905   : Phase(Compiler),
   906     _env(ci_env),
   907     _log(ci_env->log()),
   908     _compile_id(0),
   909     _save_argument_registers(save_arg_registers),
   910     _method(NULL),
   911     _stub_name(stub_name),
   912     _stub_function(stub_function),
   913     _stub_entry_point(NULL),
   914     _entry_bci(InvocationEntryBci),
   915     _initial_gvn(NULL),
   916     _for_igvn(NULL),
   917     _warm_calls(NULL),
   918     _orig_pc_slot(0),
   919     _orig_pc_slot_offset_in_bytes(0),
   920     _subsume_loads(true),
   921     _do_escape_analysis(false),
   922     _eliminate_boxing(false),
   923     _failure_reason(NULL),
   924     _code_buffer("Compile::Fill_buffer"),
   925     _has_method_handle_invokes(false),
   926     _mach_constant_base_node(NULL),
   927     _node_bundling_limit(0),
   928     _node_bundling_base(NULL),
   929     _java_calls(0),
   930     _inner_loops(0),
   931 #ifndef PRODUCT
   932     _trace_opto_output(TraceOptoOutput),
   933     _printer(NULL),
   934 #endif
   935     _dead_node_list(comp_arena()),
   936     _dead_node_count(0),
   937     _congraph(NULL),
   938     _number_of_mh_late_inlines(0),
   939     _inlining_progress(false),
   940     _inlining_incrementally(false),
   941     _print_inlining_list(NULL),
   942     _print_inlining_idx(0) {
   943   C = this;
   945 #ifndef PRODUCT
   946   TraceTime t1(NULL, &_t_totalCompilation, TimeCompiler, false);
   947   TraceTime t2(NULL, &_t_stubCompilation, TimeCompiler, false);
   948   set_print_assembly(PrintFrameConverterAssembly);
   949   set_parsed_irreducible_loop(false);
   950 #endif
   951   CompileWrapper cw(this);
   952   Init(/*AliasLevel=*/ 0);
   953   init_tf((*generator)());
   955   {
   956     // The following is a dummy for the sake of GraphKit::gen_stub
   957     Unique_Node_List for_igvn(comp_arena());
   958     set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
   959     PhaseGVN gvn(Thread::current()->resource_area(),255);
   960     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
   961     gvn.transform_no_reclaim(top());
   963     GraphKit kit;
   964     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
   965   }
   967   NOT_PRODUCT( verify_graph_edges(); )
   968   Code_Gen();
   969   if (failing())  return;
   972   // Entry point will be accessed using compile->stub_entry_point();
   973   if (code_buffer() == NULL) {
   974     Matcher::soft_match_failure();
   975   } else {
   976     if (PrintAssembly && (WizardMode || Verbose))
   977       tty->print_cr("### Stub::%s", stub_name);
   979     if (!failing()) {
   980       assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
   982       // Make the NMethod
   983       // For now we mark the frame as never safe for profile stackwalking
   984       RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
   985                                                       code_buffer(),
   986                                                       CodeOffsets::frame_never_safe,
   987                                                       // _code_offsets.value(CodeOffsets::Frame_Complete),
   988                                                       frame_size_in_words(),
   989                                                       _oop_map_set,
   990                                                       save_arg_registers);
   991       assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
   993       _stub_entry_point = rs->entry_point();
   994     }
   995   }
   996 }
   998 //------------------------------Init-------------------------------------------
   999 // Prepare for a single compilation
  1000 void Compile::Init(int aliaslevel) {
  1001   _unique  = 0;
  1002   _regalloc = NULL;
  1004   _tf      = NULL;  // filled in later
  1005   _top     = NULL;  // cached later
  1006   _matcher = NULL;  // filled in later
  1007   _cfg     = NULL;  // filled in later
  1009   set_24_bit_selection_and_mode(Use24BitFP, false);
  1011   _node_note_array = NULL;
  1012   _default_node_notes = NULL;
  1014   _immutable_memory = NULL; // filled in at first inquiry
  1016   // Globally visible Nodes
  1017   // First set TOP to NULL to give safe behavior during creation of RootNode
  1018   set_cached_top_node(NULL);
  1019   set_root(new (this) RootNode());
  1020   // Now that you have a Root to point to, create the real TOP
  1021   set_cached_top_node( new (this) ConNode(Type::TOP) );
  1022   set_recent_alloc(NULL, NULL);
  1024   // Create Debug Information Recorder to record scopes, oopmaps, etc.
  1025   env()->set_oop_recorder(new OopRecorder(env()->arena()));
  1026   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
  1027   env()->set_dependencies(new Dependencies(env()));
  1029   _fixed_slots = 0;
  1030   set_has_split_ifs(false);
  1031   set_has_loops(has_method() && method()->has_loops()); // first approximation
  1032   set_has_stringbuilder(false);
  1033   set_has_boxed_value(false);
  1034   _trap_can_recompile = false;  // no traps emitted yet
  1035   _major_progress = true; // start out assuming good things will happen
  1036   set_has_unsafe_access(false);
  1037   set_max_vector_size(0);
  1038   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
  1039   set_decompile_count(0);
  1041   set_do_freq_based_layout(BlockLayoutByFrequency || method_has_option("BlockLayoutByFrequency"));
  1042   set_num_loop_opts(LoopOptsCount);
  1043   set_do_inlining(Inline);
  1044   set_max_inline_size(MaxInlineSize);
  1045   set_freq_inline_size(FreqInlineSize);
  1046   set_do_scheduling(OptoScheduling);
  1047   set_do_count_invocations(false);
  1048   set_do_method_data_update(false);
  1050   if (debug_info()->recording_non_safepoints()) {
  1051     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
  1052                         (comp_arena(), 8, 0, NULL));
  1053     set_default_node_notes(Node_Notes::make(this));
  1056   // // -- Initialize types before each compile --
  1057   // // Update cached type information
  1058   // if( _method && _method->constants() )
  1059   //   Type::update_loaded_types(_method, _method->constants());
  1061   // Init alias_type map.
  1062   if (!_do_escape_analysis && aliaslevel == 3)
  1063     aliaslevel = 2;  // No unique types without escape analysis
  1064   _AliasLevel = aliaslevel;
  1065   const int grow_ats = 16;
  1066   _max_alias_types = grow_ats;
  1067   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
  1068   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
  1069   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
  1071     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
  1073   // Initialize the first few types.
  1074   _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
  1075   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
  1076   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
  1077   _num_alias_types = AliasIdxRaw+1;
  1078   // Zero out the alias type cache.
  1079   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
  1080   // A NULL adr_type hits in the cache right away.  Preload the right answer.
  1081   probe_alias_cache(NULL)->_index = AliasIdxTop;
  1083   _intrinsics = NULL;
  1084   _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1085   _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1086   _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1087   register_library_intrinsics();
  1090 //---------------------------init_start----------------------------------------
  1091 // Install the StartNode on this compile object.
  1092 void Compile::init_start(StartNode* s) {
  1093   if (failing())
  1094     return; // already failing
  1095   assert(s == start(), "");
  1098 StartNode* Compile::start() const {
  1099   assert(!failing(), "");
  1100   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
  1101     Node* start = root()->fast_out(i);
  1102     if( start->is_Start() )
  1103       return start->as_Start();
  1105   ShouldNotReachHere();
  1106   return NULL;
  1109 //-------------------------------immutable_memory-------------------------------------
  1110 // Access immutable memory
  1111 Node* Compile::immutable_memory() {
  1112   if (_immutable_memory != NULL) {
  1113     return _immutable_memory;
  1115   StartNode* s = start();
  1116   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
  1117     Node *p = s->fast_out(i);
  1118     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
  1119       _immutable_memory = p;
  1120       return _immutable_memory;
  1123   ShouldNotReachHere();
  1124   return NULL;
  1127 //----------------------set_cached_top_node------------------------------------
  1128 // Install the cached top node, and make sure Node::is_top works correctly.
  1129 void Compile::set_cached_top_node(Node* tn) {
  1130   if (tn != NULL)  verify_top(tn);
  1131   Node* old_top = _top;
  1132   _top = tn;
  1133   // Calling Node::setup_is_top allows the nodes the chance to adjust
  1134   // their _out arrays.
  1135   if (_top != NULL)     _top->setup_is_top();
  1136   if (old_top != NULL)  old_top->setup_is_top();
  1137   assert(_top == NULL || top()->is_top(), "");
  1140 #ifdef ASSERT
  1141 uint Compile::count_live_nodes_by_graph_walk() {
  1142   Unique_Node_List useful(comp_arena());
  1143   // Get useful node list by walking the graph.
  1144   identify_useful_nodes(useful);
  1145   return useful.size();
  1148 void Compile::print_missing_nodes() {
  1150   // Return if CompileLog is NULL and PrintIdealNodeCount is false.
  1151   if ((_log == NULL) && (! PrintIdealNodeCount)) {
  1152     return;
  1155   // This is an expensive function. It is executed only when the user
  1156   // specifies VerifyIdealNodeCount option or otherwise knows the
  1157   // additional work that needs to be done to identify reachable nodes
  1158   // by walking the flow graph and find the missing ones using
  1159   // _dead_node_list.
  1161   Unique_Node_List useful(comp_arena());
  1162   // Get useful node list by walking the graph.
  1163   identify_useful_nodes(useful);
  1165   uint l_nodes = C->live_nodes();
  1166   uint l_nodes_by_walk = useful.size();
  1168   if (l_nodes != l_nodes_by_walk) {
  1169     if (_log != NULL) {
  1170       _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
  1171       _log->stamp();
  1172       _log->end_head();
  1174     VectorSet& useful_member_set = useful.member_set();
  1175     int last_idx = l_nodes_by_walk;
  1176     for (int i = 0; i < last_idx; i++) {
  1177       if (useful_member_set.test(i)) {
  1178         if (_dead_node_list.test(i)) {
  1179           if (_log != NULL) {
  1180             _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
  1182           if (PrintIdealNodeCount) {
  1183             // Print the log message to tty
  1184               tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
  1185               useful.at(i)->dump();
  1189       else if (! _dead_node_list.test(i)) {
  1190         if (_log != NULL) {
  1191           _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
  1193         if (PrintIdealNodeCount) {
  1194           // Print the log message to tty
  1195           tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
  1199     if (_log != NULL) {
  1200       _log->tail("mismatched_nodes");
  1204 #endif
  1206 #ifndef PRODUCT
  1207 void Compile::verify_top(Node* tn) const {
  1208   if (tn != NULL) {
  1209     assert(tn->is_Con(), "top node must be a constant");
  1210     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
  1211     assert(tn->in(0) != NULL, "must have live top node");
  1214 #endif
  1217 ///-------------------Managing Per-Node Debug & Profile Info-------------------
  1219 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
  1220   guarantee(arr != NULL, "");
  1221   int num_blocks = arr->length();
  1222   if (grow_by < num_blocks)  grow_by = num_blocks;
  1223   int num_notes = grow_by * _node_notes_block_size;
  1224   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
  1225   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
  1226   while (num_notes > 0) {
  1227     arr->append(notes);
  1228     notes     += _node_notes_block_size;
  1229     num_notes -= _node_notes_block_size;
  1231   assert(num_notes == 0, "exact multiple, please");
  1234 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
  1235   if (source == NULL || dest == NULL)  return false;
  1237   if (dest->is_Con())
  1238     return false;               // Do not push debug info onto constants.
  1240 #ifdef ASSERT
  1241   // Leave a bread crumb trail pointing to the original node:
  1242   if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
  1243     dest->set_debug_orig(source);
  1245 #endif
  1247   if (node_note_array() == NULL)
  1248     return false;               // Not collecting any notes now.
  1250   // This is a copy onto a pre-existing node, which may already have notes.
  1251   // If both nodes have notes, do not overwrite any pre-existing notes.
  1252   Node_Notes* source_notes = node_notes_at(source->_idx);
  1253   if (source_notes == NULL || source_notes->is_clear())  return false;
  1254   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
  1255   if (dest_notes == NULL || dest_notes->is_clear()) {
  1256     return set_node_notes_at(dest->_idx, source_notes);
  1259   Node_Notes merged_notes = (*source_notes);
  1260   // The order of operations here ensures that dest notes will win...
  1261   merged_notes.update_from(dest_notes);
  1262   return set_node_notes_at(dest->_idx, &merged_notes);
  1266 //--------------------------allow_range_check_smearing-------------------------
  1267 // Gating condition for coalescing similar range checks.
  1268 // Sometimes we try 'speculatively' replacing a series of a range checks by a
  1269 // single covering check that is at least as strong as any of them.
  1270 // If the optimization succeeds, the simplified (strengthened) range check
  1271 // will always succeed.  If it fails, we will deopt, and then give up
  1272 // on the optimization.
  1273 bool Compile::allow_range_check_smearing() const {
  1274   // If this method has already thrown a range-check,
  1275   // assume it was because we already tried range smearing
  1276   // and it failed.
  1277   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
  1278   return !already_trapped;
  1282 //------------------------------flatten_alias_type-----------------------------
  1283 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
  1284   int offset = tj->offset();
  1285   TypePtr::PTR ptr = tj->ptr();
  1287   // Known instance (scalarizable allocation) alias only with itself.
  1288   bool is_known_inst = tj->isa_oopptr() != NULL &&
  1289                        tj->is_oopptr()->is_known_instance();
  1291   // Process weird unsafe references.
  1292   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
  1293     assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
  1294     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
  1295     tj = TypeOopPtr::BOTTOM;
  1296     ptr = tj->ptr();
  1297     offset = tj->offset();
  1300   // Array pointers need some flattening
  1301   const TypeAryPtr *ta = tj->isa_aryptr();
  1302   if (ta && ta->is_stable()) {
  1303     // Erase stability property for alias analysis.
  1304     tj = ta = ta->cast_to_stable(false);
  1306   if( ta && is_known_inst ) {
  1307     if ( offset != Type::OffsetBot &&
  1308          offset > arrayOopDesc::length_offset_in_bytes() ) {
  1309       offset = Type::OffsetBot; // Flatten constant access into array body only
  1310       tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
  1312   } else if( ta && _AliasLevel >= 2 ) {
  1313     // For arrays indexed by constant indices, we flatten the alias
  1314     // space to include all of the array body.  Only the header, klass
  1315     // and array length can be accessed un-aliased.
  1316     if( offset != Type::OffsetBot ) {
  1317       if( ta->const_oop() ) { // MethodData* or Method*
  1318         offset = Type::OffsetBot;   // Flatten constant access into array body
  1319         tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
  1320       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
  1321         // range is OK as-is.
  1322         tj = ta = TypeAryPtr::RANGE;
  1323       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
  1324         tj = TypeInstPtr::KLASS; // all klass loads look alike
  1325         ta = TypeAryPtr::RANGE; // generic ignored junk
  1326         ptr = TypePtr::BotPTR;
  1327       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
  1328         tj = TypeInstPtr::MARK;
  1329         ta = TypeAryPtr::RANGE; // generic ignored junk
  1330         ptr = TypePtr::BotPTR;
  1331       } else {                  // Random constant offset into array body
  1332         offset = Type::OffsetBot;   // Flatten constant access into array body
  1333         tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
  1336     // Arrays of fixed size alias with arrays of unknown size.
  1337     if (ta->size() != TypeInt::POS) {
  1338       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
  1339       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
  1341     // Arrays of known objects become arrays of unknown objects.
  1342     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
  1343       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
  1344       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
  1346     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
  1347       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
  1348       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
  1350     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
  1351     // cannot be distinguished by bytecode alone.
  1352     if (ta->elem() == TypeInt::BOOL) {
  1353       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
  1354       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
  1355       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
  1357     // During the 2nd round of IterGVN, NotNull castings are removed.
  1358     // Make sure the Bottom and NotNull variants alias the same.
  1359     // Also, make sure exact and non-exact variants alias the same.
  1360     if( ptr == TypePtr::NotNull || ta->klass_is_exact() ) {
  1361       tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
  1365   // Oop pointers need some flattening
  1366   const TypeInstPtr *to = tj->isa_instptr();
  1367   if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
  1368     ciInstanceKlass *k = to->klass()->as_instance_klass();
  1369     if( ptr == TypePtr::Constant ) {
  1370       if (to->klass() != ciEnv::current()->Class_klass() ||
  1371           offset < k->size_helper() * wordSize) {
  1372         // No constant oop pointers (such as Strings); they alias with
  1373         // unknown strings.
  1374         assert(!is_known_inst, "not scalarizable allocation");
  1375         tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
  1377     } else if( is_known_inst ) {
  1378       tj = to; // Keep NotNull and klass_is_exact for instance type
  1379     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
  1380       // During the 2nd round of IterGVN, NotNull castings are removed.
  1381       // Make sure the Bottom and NotNull variants alias the same.
  1382       // Also, make sure exact and non-exact variants alias the same.
  1383       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
  1385     // Canonicalize the holder of this field
  1386     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
  1387       // First handle header references such as a LoadKlassNode, even if the
  1388       // object's klass is unloaded at compile time (4965979).
  1389       if (!is_known_inst) { // Do it only for non-instance types
  1390         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
  1392     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
  1393       // Static fields are in the space above the normal instance
  1394       // fields in the java.lang.Class instance.
  1395       if (to->klass() != ciEnv::current()->Class_klass()) {
  1396         to = NULL;
  1397         tj = TypeOopPtr::BOTTOM;
  1398         offset = tj->offset();
  1400     } else {
  1401       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
  1402       if (!k->equals(canonical_holder) || tj->offset() != offset) {
  1403         if( is_known_inst ) {
  1404           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
  1405         } else {
  1406           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
  1412   // Klass pointers to object array klasses need some flattening
  1413   const TypeKlassPtr *tk = tj->isa_klassptr();
  1414   if( tk ) {
  1415     // If we are referencing a field within a Klass, we need
  1416     // to assume the worst case of an Object.  Both exact and
  1417     // inexact types must flatten to the same alias class so
  1418     // use NotNull as the PTR.
  1419     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
  1421       tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
  1422                                    TypeKlassPtr::OBJECT->klass(),
  1423                                    offset);
  1426     ciKlass* klass = tk->klass();
  1427     if( klass->is_obj_array_klass() ) {
  1428       ciKlass* k = TypeAryPtr::OOPS->klass();
  1429       if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
  1430         k = TypeInstPtr::BOTTOM->klass();
  1431       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
  1434     // Check for precise loads from the primary supertype array and force them
  1435     // to the supertype cache alias index.  Check for generic array loads from
  1436     // the primary supertype array and also force them to the supertype cache
  1437     // alias index.  Since the same load can reach both, we need to merge
  1438     // these 2 disparate memories into the same alias class.  Since the
  1439     // primary supertype array is read-only, there's no chance of confusion
  1440     // where we bypass an array load and an array store.
  1441     int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
  1442     if (offset == Type::OffsetBot ||
  1443         (offset >= primary_supers_offset &&
  1444          offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
  1445         offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
  1446       offset = in_bytes(Klass::secondary_super_cache_offset());
  1447       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
  1451   // Flatten all Raw pointers together.
  1452   if (tj->base() == Type::RawPtr)
  1453     tj = TypeRawPtr::BOTTOM;
  1455   if (tj->base() == Type::AnyPtr)
  1456     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
  1458   // Flatten all to bottom for now
  1459   switch( _AliasLevel ) {
  1460   case 0:
  1461     tj = TypePtr::BOTTOM;
  1462     break;
  1463   case 1:                       // Flatten to: oop, static, field or array
  1464     switch (tj->base()) {
  1465     //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
  1466     case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
  1467     case Type::AryPtr:   // do not distinguish arrays at all
  1468     case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
  1469     case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
  1470     case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
  1471     default: ShouldNotReachHere();
  1473     break;
  1474   case 2:                       // No collapsing at level 2; keep all splits
  1475   case 3:                       // No collapsing at level 3; keep all splits
  1476     break;
  1477   default:
  1478     Unimplemented();
  1481   offset = tj->offset();
  1482   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
  1484   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
  1485           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
  1486           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
  1487           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
  1488           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
  1489           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
  1490           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr)  ,
  1491           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
  1492   assert( tj->ptr() != TypePtr::TopPTR &&
  1493           tj->ptr() != TypePtr::AnyNull &&
  1494           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
  1495 //    assert( tj->ptr() != TypePtr::Constant ||
  1496 //            tj->base() == Type::RawPtr ||
  1497 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
  1499   return tj;
  1502 void Compile::AliasType::Init(int i, const TypePtr* at) {
  1503   _index = i;
  1504   _adr_type = at;
  1505   _field = NULL;
  1506   _element = NULL;
  1507   _is_rewritable = true; // default
  1508   const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
  1509   if (atoop != NULL && atoop->is_known_instance()) {
  1510     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
  1511     _general_index = Compile::current()->get_alias_index(gt);
  1512   } else {
  1513     _general_index = 0;
  1517 //---------------------------------print_on------------------------------------
  1518 #ifndef PRODUCT
  1519 void Compile::AliasType::print_on(outputStream* st) {
  1520   if (index() < 10)
  1521         st->print("@ <%d> ", index());
  1522   else  st->print("@ <%d>",  index());
  1523   st->print(is_rewritable() ? "   " : " RO");
  1524   int offset = adr_type()->offset();
  1525   if (offset == Type::OffsetBot)
  1526         st->print(" +any");
  1527   else  st->print(" +%-3d", offset);
  1528   st->print(" in ");
  1529   adr_type()->dump_on(st);
  1530   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
  1531   if (field() != NULL && tjp) {
  1532     if (tjp->klass()  != field()->holder() ||
  1533         tjp->offset() != field()->offset_in_bytes()) {
  1534       st->print(" != ");
  1535       field()->print();
  1536       st->print(" ***");
  1541 void print_alias_types() {
  1542   Compile* C = Compile::current();
  1543   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
  1544   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
  1545     C->alias_type(idx)->print_on(tty);
  1546     tty->cr();
  1549 #endif
  1552 //----------------------------probe_alias_cache--------------------------------
  1553 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
  1554   intptr_t key = (intptr_t) adr_type;
  1555   key ^= key >> logAliasCacheSize;
  1556   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
  1560 //-----------------------------grow_alias_types--------------------------------
  1561 void Compile::grow_alias_types() {
  1562   const int old_ats  = _max_alias_types; // how many before?
  1563   const int new_ats  = old_ats;          // how many more?
  1564   const int grow_ats = old_ats+new_ats;  // how many now?
  1565   _max_alias_types = grow_ats;
  1566   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
  1567   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
  1568   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
  1569   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
  1573 //--------------------------------find_alias_type------------------------------
  1574 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
  1575   if (_AliasLevel == 0)
  1576     return alias_type(AliasIdxBot);
  1578   AliasCacheEntry* ace = probe_alias_cache(adr_type);
  1579   if (ace->_adr_type == adr_type) {
  1580     return alias_type(ace->_index);
  1583   // Handle special cases.
  1584   if (adr_type == NULL)             return alias_type(AliasIdxTop);
  1585   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
  1587   // Do it the slow way.
  1588   const TypePtr* flat = flatten_alias_type(adr_type);
  1590 #ifdef ASSERT
  1591   assert(flat == flatten_alias_type(flat), "idempotent");
  1592   assert(flat != TypePtr::BOTTOM,     "cannot alias-analyze an untyped ptr");
  1593   if (flat->isa_oopptr() && !flat->isa_klassptr()) {
  1594     const TypeOopPtr* foop = flat->is_oopptr();
  1595     // Scalarizable allocations have exact klass always.
  1596     bool exact = !foop->klass_is_exact() || foop->is_known_instance();
  1597     const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
  1598     assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type");
  1600   assert(flat == flatten_alias_type(flat), "exact bit doesn't matter");
  1601 #endif
  1603   int idx = AliasIdxTop;
  1604   for (int i = 0; i < num_alias_types(); i++) {
  1605     if (alias_type(i)->adr_type() == flat) {
  1606       idx = i;
  1607       break;
  1611   if (idx == AliasIdxTop) {
  1612     if (no_create)  return NULL;
  1613     // Grow the array if necessary.
  1614     if (_num_alias_types == _max_alias_types)  grow_alias_types();
  1615     // Add a new alias type.
  1616     idx = _num_alias_types++;
  1617     _alias_types[idx]->Init(idx, flat);
  1618     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
  1619     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
  1620     if (flat->isa_instptr()) {
  1621       if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
  1622           && flat->is_instptr()->klass() == env()->Class_klass())
  1623         alias_type(idx)->set_rewritable(false);
  1625     if (flat->isa_aryptr()) {
  1626 #ifdef ASSERT
  1627       const int header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
  1628       // (T_BYTE has the weakest alignment and size restrictions...)
  1629       assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
  1630 #endif
  1631       if (flat->offset() == TypePtr::OffsetBot) {
  1632         alias_type(idx)->set_element(flat->is_aryptr()->elem());
  1635     if (flat->isa_klassptr()) {
  1636       if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
  1637         alias_type(idx)->set_rewritable(false);
  1638       if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
  1639         alias_type(idx)->set_rewritable(false);
  1640       if (flat->offset() == in_bytes(Klass::access_flags_offset()))
  1641         alias_type(idx)->set_rewritable(false);
  1642       if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
  1643         alias_type(idx)->set_rewritable(false);
  1645     // %%% (We would like to finalize JavaThread::threadObj_offset(),
  1646     // but the base pointer type is not distinctive enough to identify
  1647     // references into JavaThread.)
  1649     // Check for final fields.
  1650     const TypeInstPtr* tinst = flat->isa_instptr();
  1651     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
  1652       ciField* field;
  1653       if (tinst->const_oop() != NULL &&
  1654           tinst->klass() == ciEnv::current()->Class_klass() &&
  1655           tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
  1656         // static field
  1657         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
  1658         field = k->get_field_by_offset(tinst->offset(), true);
  1659       } else {
  1660         ciInstanceKlass *k = tinst->klass()->as_instance_klass();
  1661         field = k->get_field_by_offset(tinst->offset(), false);
  1663       assert(field == NULL ||
  1664              original_field == NULL ||
  1665              (field->holder() == original_field->holder() &&
  1666               field->offset() == original_field->offset() &&
  1667               field->is_static() == original_field->is_static()), "wrong field?");
  1668       // Set field() and is_rewritable() attributes.
  1669       if (field != NULL)  alias_type(idx)->set_field(field);
  1673   // Fill the cache for next time.
  1674   ace->_adr_type = adr_type;
  1675   ace->_index    = idx;
  1676   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
  1678   // Might as well try to fill the cache for the flattened version, too.
  1679   AliasCacheEntry* face = probe_alias_cache(flat);
  1680   if (face->_adr_type == NULL) {
  1681     face->_adr_type = flat;
  1682     face->_index    = idx;
  1683     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
  1686   return alias_type(idx);
  1690 Compile::AliasType* Compile::alias_type(ciField* field) {
  1691   const TypeOopPtr* t;
  1692   if (field->is_static())
  1693     t = TypeInstPtr::make(field->holder()->java_mirror());
  1694   else
  1695     t = TypeOopPtr::make_from_klass_raw(field->holder());
  1696   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
  1697   assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
  1698   return atp;
  1702 //------------------------------have_alias_type--------------------------------
  1703 bool Compile::have_alias_type(const TypePtr* adr_type) {
  1704   AliasCacheEntry* ace = probe_alias_cache(adr_type);
  1705   if (ace->_adr_type == adr_type) {
  1706     return true;
  1709   // Handle special cases.
  1710   if (adr_type == NULL)             return true;
  1711   if (adr_type == TypePtr::BOTTOM)  return true;
  1713   return find_alias_type(adr_type, true, NULL) != NULL;
  1716 //-----------------------------must_alias--------------------------------------
  1717 // True if all values of the given address type are in the given alias category.
  1718 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
  1719   if (alias_idx == AliasIdxBot)         return true;  // the universal category
  1720   if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
  1721   if (alias_idx == AliasIdxTop)         return false; // the empty category
  1722   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
  1724   // the only remaining possible overlap is identity
  1725   int adr_idx = get_alias_index(adr_type);
  1726   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
  1727   assert(adr_idx == alias_idx ||
  1728          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
  1729           && adr_type                       != TypeOopPtr::BOTTOM),
  1730          "should not be testing for overlap with an unsafe pointer");
  1731   return adr_idx == alias_idx;
  1734 //------------------------------can_alias--------------------------------------
  1735 // True if any values of the given address type are in the given alias category.
  1736 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
  1737   if (alias_idx == AliasIdxTop)         return false; // the empty category
  1738   if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
  1739   if (alias_idx == AliasIdxBot)         return true;  // the universal category
  1740   if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
  1742   // the only remaining possible overlap is identity
  1743   int adr_idx = get_alias_index(adr_type);
  1744   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
  1745   return adr_idx == alias_idx;
  1750 //---------------------------pop_warm_call-------------------------------------
  1751 WarmCallInfo* Compile::pop_warm_call() {
  1752   WarmCallInfo* wci = _warm_calls;
  1753   if (wci != NULL)  _warm_calls = wci->remove_from(wci);
  1754   return wci;
  1757 //----------------------------Inline_Warm--------------------------------------
  1758 int Compile::Inline_Warm() {
  1759   // If there is room, try to inline some more warm call sites.
  1760   // %%% Do a graph index compaction pass when we think we're out of space?
  1761   if (!InlineWarmCalls)  return 0;
  1763   int calls_made_hot = 0;
  1764   int room_to_grow   = NodeCountInliningCutoff - unique();
  1765   int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
  1766   int amount_grown   = 0;
  1767   WarmCallInfo* call;
  1768   while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
  1769     int est_size = (int)call->size();
  1770     if (est_size > (room_to_grow - amount_grown)) {
  1771       // This one won't fit anyway.  Get rid of it.
  1772       call->make_cold();
  1773       continue;
  1775     call->make_hot();
  1776     calls_made_hot++;
  1777     amount_grown   += est_size;
  1778     amount_to_grow -= est_size;
  1781   if (calls_made_hot > 0)  set_major_progress();
  1782   return calls_made_hot;
  1786 //----------------------------Finish_Warm--------------------------------------
  1787 void Compile::Finish_Warm() {
  1788   if (!InlineWarmCalls)  return;
  1789   if (failing())  return;
  1790   if (warm_calls() == NULL)  return;
  1792   // Clean up loose ends, if we are out of space for inlining.
  1793   WarmCallInfo* call;
  1794   while ((call = pop_warm_call()) != NULL) {
  1795     call->make_cold();
  1799 //---------------------cleanup_loop_predicates-----------------------
  1800 // Remove the opaque nodes that protect the predicates so that all unused
  1801 // checks and uncommon_traps will be eliminated from the ideal graph
  1802 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
  1803   if (predicate_count()==0) return;
  1804   for (int i = predicate_count(); i > 0; i--) {
  1805     Node * n = predicate_opaque1_node(i-1);
  1806     assert(n->Opcode() == Op_Opaque1, "must be");
  1807     igvn.replace_node(n, n->in(1));
  1809   assert(predicate_count()==0, "should be clean!");
  1812 // StringOpts and late inlining of string methods
  1813 void Compile::inline_string_calls(bool parse_time) {
  1815     // remove useless nodes to make the usage analysis simpler
  1816     ResourceMark rm;
  1817     PhaseRemoveUseless pru(initial_gvn(), for_igvn());
  1821     ResourceMark rm;
  1822     print_method(PHASE_BEFORE_STRINGOPTS, 3);
  1823     PhaseStringOpts pso(initial_gvn(), for_igvn());
  1824     print_method(PHASE_AFTER_STRINGOPTS, 3);
  1827   // now inline anything that we skipped the first time around
  1828   if (!parse_time) {
  1829     _late_inlines_pos = _late_inlines.length();
  1832   while (_string_late_inlines.length() > 0) {
  1833     CallGenerator* cg = _string_late_inlines.pop();
  1834     cg->do_late_inline();
  1835     if (failing())  return;
  1837   _string_late_inlines.trunc_to(0);
  1840 // Late inlining of boxing methods
  1841 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
  1842   if (_boxing_late_inlines.length() > 0) {
  1843     assert(has_boxed_value(), "inconsistent");
  1845     PhaseGVN* gvn = initial_gvn();
  1846     set_inlining_incrementally(true);
  1848     assert( igvn._worklist.size() == 0, "should be done with igvn" );
  1849     for_igvn()->clear();
  1850     gvn->replace_with(&igvn);
  1852     while (_boxing_late_inlines.length() > 0) {
  1853       CallGenerator* cg = _boxing_late_inlines.pop();
  1854       cg->do_late_inline();
  1855       if (failing())  return;
  1857     _boxing_late_inlines.trunc_to(0);
  1860       ResourceMark rm;
  1861       PhaseRemoveUseless pru(gvn, for_igvn());
  1864     igvn = PhaseIterGVN(gvn);
  1865     igvn.optimize();
  1867     set_inlining_progress(false);
  1868     set_inlining_incrementally(false);
  1872 void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
  1873   assert(IncrementalInline, "incremental inlining should be on");
  1874   PhaseGVN* gvn = initial_gvn();
  1876   set_inlining_progress(false);
  1877   for_igvn()->clear();
  1878   gvn->replace_with(&igvn);
  1880   int i = 0;
  1882   for (; i <_late_inlines.length() && !inlining_progress(); i++) {
  1883     CallGenerator* cg = _late_inlines.at(i);
  1884     _late_inlines_pos = i+1;
  1885     cg->do_late_inline();
  1886     if (failing())  return;
  1888   int j = 0;
  1889   for (; i < _late_inlines.length(); i++, j++) {
  1890     _late_inlines.at_put(j, _late_inlines.at(i));
  1892   _late_inlines.trunc_to(j);
  1895     ResourceMark rm;
  1896     PhaseRemoveUseless pru(gvn, for_igvn());
  1899   igvn = PhaseIterGVN(gvn);
  1902 // Perform incremental inlining until bound on number of live nodes is reached
  1903 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
  1904   PhaseGVN* gvn = initial_gvn();
  1906   set_inlining_incrementally(true);
  1907   set_inlining_progress(true);
  1908   uint low_live_nodes = 0;
  1910   while(inlining_progress() && _late_inlines.length() > 0) {
  1912     if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
  1913       if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
  1914         // PhaseIdealLoop is expensive so we only try it once we are
  1915         // out of loop and we only try it again if the previous helped
  1916         // got the number of nodes down significantly
  1917         PhaseIdealLoop ideal_loop( igvn, false, true );
  1918         if (failing())  return;
  1919         low_live_nodes = live_nodes();
  1920         _major_progress = true;
  1923       if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
  1924         break;
  1928     inline_incrementally_one(igvn);
  1930     if (failing())  return;
  1932     igvn.optimize();
  1934     if (failing())  return;
  1937   assert( igvn._worklist.size() == 0, "should be done with igvn" );
  1939   if (_string_late_inlines.length() > 0) {
  1940     assert(has_stringbuilder(), "inconsistent");
  1941     for_igvn()->clear();
  1942     initial_gvn()->replace_with(&igvn);
  1944     inline_string_calls(false);
  1946     if (failing())  return;
  1949       ResourceMark rm;
  1950       PhaseRemoveUseless pru(initial_gvn(), for_igvn());
  1953     igvn = PhaseIterGVN(gvn);
  1955     igvn.optimize();
  1958   set_inlining_incrementally(false);
  1962 //------------------------------Optimize---------------------------------------
  1963 // Given a graph, optimize it.
  1964 void Compile::Optimize() {
  1965   TracePhase t1("optimizer", &_t_optimizer, true);
  1967 #ifndef PRODUCT
  1968   if (env()->break_at_compile()) {
  1969     BREAKPOINT;
  1972 #endif
  1974   ResourceMark rm;
  1975   int          loop_opts_cnt;
  1977   NOT_PRODUCT( verify_graph_edges(); )
  1979   print_method(PHASE_AFTER_PARSING);
  1982   // Iterative Global Value Numbering, including ideal transforms
  1983   // Initialize IterGVN with types and values from parse-time GVN
  1984   PhaseIterGVN igvn(initial_gvn());
  1986     NOT_PRODUCT( TracePhase t2("iterGVN", &_t_iterGVN, TimeCompiler); )
  1987     igvn.optimize();
  1990   print_method(PHASE_ITER_GVN1, 2);
  1992   if (failing())  return;
  1995     NOT_PRODUCT( TracePhase t2("incrementalInline", &_t_incrInline, TimeCompiler); )
  1996     inline_incrementally(igvn);
  1999   print_method(PHASE_INCREMENTAL_INLINE, 2);
  2001   if (failing())  return;
  2003   if (eliminate_boxing()) {
  2004     NOT_PRODUCT( TracePhase t2("incrementalInline", &_t_incrInline, TimeCompiler); )
  2005     // Inline valueOf() methods now.
  2006     inline_boxing_calls(igvn);
  2008     print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
  2010     if (failing())  return;
  2013   // No more new expensive nodes will be added to the list from here
  2014   // so keep only the actual candidates for optimizations.
  2015   cleanup_expensive_nodes(igvn);
  2017   // Perform escape analysis
  2018   if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
  2019     if (has_loops()) {
  2020       // Cleanup graph (remove dead nodes).
  2021       TracePhase t2("idealLoop", &_t_idealLoop, true);
  2022       PhaseIdealLoop ideal_loop( igvn, false, true );
  2023       if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
  2024       if (failing())  return;
  2026     ConnectionGraph::do_analysis(this, &igvn);
  2028     if (failing())  return;
  2030     // Optimize out fields loads from scalar replaceable allocations.
  2031     igvn.optimize();
  2032     print_method(PHASE_ITER_GVN_AFTER_EA, 2);
  2034     if (failing())  return;
  2036     if (congraph() != NULL && macro_count() > 0) {
  2037       NOT_PRODUCT( TracePhase t2("macroEliminate", &_t_macroEliminate, TimeCompiler); )
  2038       PhaseMacroExpand mexp(igvn);
  2039       mexp.eliminate_macro_nodes();
  2040       igvn.set_delay_transform(false);
  2042       igvn.optimize();
  2043       print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
  2045       if (failing())  return;
  2049   // Loop transforms on the ideal graph.  Range Check Elimination,
  2050   // peeling, unrolling, etc.
  2052   // Set loop opts counter
  2053   loop_opts_cnt = num_loop_opts();
  2054   if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
  2056       TracePhase t2("idealLoop", &_t_idealLoop, true);
  2057       PhaseIdealLoop ideal_loop( igvn, true );
  2058       loop_opts_cnt--;
  2059       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
  2060       if (failing())  return;
  2062     // Loop opts pass if partial peeling occurred in previous pass
  2063     if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
  2064       TracePhase t3("idealLoop", &_t_idealLoop, true);
  2065       PhaseIdealLoop ideal_loop( igvn, false );
  2066       loop_opts_cnt--;
  2067       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
  2068       if (failing())  return;
  2070     // Loop opts pass for loop-unrolling before CCP
  2071     if(major_progress() && (loop_opts_cnt > 0)) {
  2072       TracePhase t4("idealLoop", &_t_idealLoop, true);
  2073       PhaseIdealLoop ideal_loop( igvn, false );
  2074       loop_opts_cnt--;
  2075       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
  2077     if (!failing()) {
  2078       // Verify that last round of loop opts produced a valid graph
  2079       NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
  2080       PhaseIdealLoop::verify(igvn);
  2083   if (failing())  return;
  2085   // Conditional Constant Propagation;
  2086   PhaseCCP ccp( &igvn );
  2087   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
  2089     TracePhase t2("ccp", &_t_ccp, true);
  2090     ccp.do_transform();
  2092   print_method(PHASE_CPP1, 2);
  2094   assert( true, "Break here to ccp.dump_old2new_map()");
  2096   // Iterative Global Value Numbering, including ideal transforms
  2098     NOT_PRODUCT( TracePhase t2("iterGVN2", &_t_iterGVN2, TimeCompiler); )
  2099     igvn = ccp;
  2100     igvn.optimize();
  2103   print_method(PHASE_ITER_GVN2, 2);
  2105   if (failing())  return;
  2107   // Loop transforms on the ideal graph.  Range Check Elimination,
  2108   // peeling, unrolling, etc.
  2109   if(loop_opts_cnt > 0) {
  2110     debug_only( int cnt = 0; );
  2111     while(major_progress() && (loop_opts_cnt > 0)) {
  2112       TracePhase t2("idealLoop", &_t_idealLoop, true);
  2113       assert( cnt++ < 40, "infinite cycle in loop optimization" );
  2114       PhaseIdealLoop ideal_loop( igvn, true);
  2115       loop_opts_cnt--;
  2116       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
  2117       if (failing())  return;
  2122     // Verify that all previous optimizations produced a valid graph
  2123     // at least to this point, even if no loop optimizations were done.
  2124     NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
  2125     PhaseIdealLoop::verify(igvn);
  2129     NOT_PRODUCT( TracePhase t2("macroExpand", &_t_macroExpand, TimeCompiler); )
  2130     PhaseMacroExpand  mex(igvn);
  2131     if (mex.expand_macro_nodes()) {
  2132       assert(failing(), "must bail out w/ explicit message");
  2133       return;
  2137  } // (End scope of igvn; run destructor if necessary for asserts.)
  2139   dump_inlining();
  2140   // A method with only infinite loops has no edges entering loops from root
  2142     NOT_PRODUCT( TracePhase t2("graphReshape", &_t_graphReshaping, TimeCompiler); )
  2143     if (final_graph_reshaping()) {
  2144       assert(failing(), "must bail out w/ explicit message");
  2145       return;
  2149   print_method(PHASE_OPTIMIZE_FINISHED, 2);
  2153 //------------------------------Code_Gen---------------------------------------
  2154 // Given a graph, generate code for it
  2155 void Compile::Code_Gen() {
  2156   if (failing()) {
  2157     return;
  2160   // Perform instruction selection.  You might think we could reclaim Matcher
  2161   // memory PDQ, but actually the Matcher is used in generating spill code.
  2162   // Internals of the Matcher (including some VectorSets) must remain live
  2163   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
  2164   // set a bit in reclaimed memory.
  2166   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
  2167   // nodes.  Mapping is only valid at the root of each matched subtree.
  2168   NOT_PRODUCT( verify_graph_edges(); )
  2170   Matcher matcher;
  2171   _matcher = &matcher;
  2173     TracePhase t2("matcher", &_t_matcher, true);
  2174     matcher.match();
  2176   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
  2177   // nodes.  Mapping is only valid at the root of each matched subtree.
  2178   NOT_PRODUCT( verify_graph_edges(); )
  2180   // If you have too many nodes, or if matching has failed, bail out
  2181   check_node_count(0, "out of nodes matching instructions");
  2182   if (failing()) {
  2183     return;
  2186   // Build a proper-looking CFG
  2187   PhaseCFG cfg(node_arena(), root(), matcher);
  2188   _cfg = &cfg;
  2190     NOT_PRODUCT( TracePhase t2("scheduler", &_t_scheduler, TimeCompiler); )
  2191     bool success = cfg.do_global_code_motion();
  2192     if (!success) {
  2193       return;
  2196     print_method(PHASE_GLOBAL_CODE_MOTION, 2);
  2197     NOT_PRODUCT( verify_graph_edges(); )
  2198     debug_only( cfg.verify(); )
  2201   PhaseChaitin regalloc(unique(), cfg, matcher);
  2202   _regalloc = &regalloc;
  2204     TracePhase t2("regalloc", &_t_registerAllocation, true);
  2205     // Perform register allocation.  After Chaitin, use-def chains are
  2206     // no longer accurate (at spill code) and so must be ignored.
  2207     // Node->LRG->reg mappings are still accurate.
  2208     _regalloc->Register_Allocate();
  2210     // Bail out if the allocator builds too many nodes
  2211     if (failing()) {
  2212       return;
  2216   // Prior to register allocation we kept empty basic blocks in case the
  2217   // the allocator needed a place to spill.  After register allocation we
  2218   // are not adding any new instructions.  If any basic block is empty, we
  2219   // can now safely remove it.
  2221     NOT_PRODUCT( TracePhase t2("blockOrdering", &_t_blockOrdering, TimeCompiler); )
  2222     cfg.remove_empty_blocks();
  2223     if (do_freq_based_layout()) {
  2224       PhaseBlockLayout layout(cfg);
  2225     } else {
  2226       cfg.set_loop_alignment();
  2228     cfg.fixup_flow();
  2231   // Apply peephole optimizations
  2232   if( OptoPeephole ) {
  2233     NOT_PRODUCT( TracePhase t2("peephole", &_t_peephole, TimeCompiler); )
  2234     PhasePeephole peep( _regalloc, cfg);
  2235     peep.do_transform();
  2238   // Convert Nodes to instruction bits in a buffer
  2240     // %%%% workspace merge brought two timers together for one job
  2241     TracePhase t2a("output", &_t_output, true);
  2242     NOT_PRODUCT( TraceTime t2b(NULL, &_t_codeGeneration, TimeCompiler, false); )
  2243     Output();
  2246   print_method(PHASE_FINAL_CODE);
  2248   // He's dead, Jim.
  2249   _cfg     = (PhaseCFG*)0xdeadbeef;
  2250   _regalloc = (PhaseChaitin*)0xdeadbeef;
  2254 //------------------------------dump_asm---------------------------------------
  2255 // Dump formatted assembly
  2256 #ifndef PRODUCT
  2257 void Compile::dump_asm(int *pcs, uint pc_limit) {
  2258   bool cut_short = false;
  2259   tty->print_cr("#");
  2260   tty->print("#  ");  _tf->dump();  tty->cr();
  2261   tty->print_cr("#");
  2263   // For all blocks
  2264   int pc = 0x0;                 // Program counter
  2265   char starts_bundle = ' ';
  2266   _regalloc->dump_frame();
  2268   Node *n = NULL;
  2269   for (uint i = 0; i < _cfg->number_of_blocks(); i++) {
  2270     if (VMThread::should_terminate()) {
  2271       cut_short = true;
  2272       break;
  2274     Block* block = _cfg->get_block(i);
  2275     if (block->is_connector() && !Verbose) {
  2276       continue;
  2278     n = block->head();
  2279     if (pcs && n->_idx < pc_limit) {
  2280       tty->print("%3.3x   ", pcs[n->_idx]);
  2281     } else {
  2282       tty->print("      ");
  2284     block->dump_head(_cfg);
  2285     if (block->is_connector()) {
  2286       tty->print_cr("        # Empty connector block");
  2287     } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
  2288       tty->print_cr("        # Block is sole successor of call");
  2291     // For all instructions
  2292     Node *delay = NULL;
  2293     for (uint j = 0; j < block->number_of_nodes(); j++) {
  2294       if (VMThread::should_terminate()) {
  2295         cut_short = true;
  2296         break;
  2298       n = block->get_node(j);
  2299       if (valid_bundle_info(n)) {
  2300         Bundle* bundle = node_bundling(n);
  2301         if (bundle->used_in_unconditional_delay()) {
  2302           delay = n;
  2303           continue;
  2305         if (bundle->starts_bundle()) {
  2306           starts_bundle = '+';
  2310       if (WizardMode) {
  2311         n->dump();
  2314       if( !n->is_Region() &&    // Dont print in the Assembly
  2315           !n->is_Phi() &&       // a few noisely useless nodes
  2316           !n->is_Proj() &&
  2317           !n->is_MachTemp() &&
  2318           !n->is_SafePointScalarObject() &&
  2319           !n->is_Catch() &&     // Would be nice to print exception table targets
  2320           !n->is_MergeMem() &&  // Not very interesting
  2321           !n->is_top() &&       // Debug info table constants
  2322           !(n->is_Con() && !n->is_Mach())// Debug info table constants
  2323           ) {
  2324         if (pcs && n->_idx < pc_limit)
  2325           tty->print("%3.3x", pcs[n->_idx]);
  2326         else
  2327           tty->print("   ");
  2328         tty->print(" %c ", starts_bundle);
  2329         starts_bundle = ' ';
  2330         tty->print("\t");
  2331         n->format(_regalloc, tty);
  2332         tty->cr();
  2335       // If we have an instruction with a delay slot, and have seen a delay,
  2336       // then back up and print it
  2337       if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
  2338         assert(delay != NULL, "no unconditional delay instruction");
  2339         if (WizardMode) delay->dump();
  2341         if (node_bundling(delay)->starts_bundle())
  2342           starts_bundle = '+';
  2343         if (pcs && n->_idx < pc_limit)
  2344           tty->print("%3.3x", pcs[n->_idx]);
  2345         else
  2346           tty->print("   ");
  2347         tty->print(" %c ", starts_bundle);
  2348         starts_bundle = ' ';
  2349         tty->print("\t");
  2350         delay->format(_regalloc, tty);
  2351         tty->print_cr("");
  2352         delay = NULL;
  2355       // Dump the exception table as well
  2356       if( n->is_Catch() && (Verbose || WizardMode) ) {
  2357         // Print the exception table for this offset
  2358         _handler_table.print_subtable_for(pc);
  2362     if (pcs && n->_idx < pc_limit)
  2363       tty->print_cr("%3.3x", pcs[n->_idx]);
  2364     else
  2365       tty->print_cr("");
  2367     assert(cut_short || delay == NULL, "no unconditional delay branch");
  2369   } // End of per-block dump
  2370   tty->print_cr("");
  2372   if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
  2374 #endif
  2376 //------------------------------Final_Reshape_Counts---------------------------
  2377 // This class defines counters to help identify when a method
  2378 // may/must be executed using hardware with only 24-bit precision.
  2379 struct Final_Reshape_Counts : public StackObj {
  2380   int  _call_count;             // count non-inlined 'common' calls
  2381   int  _float_count;            // count float ops requiring 24-bit precision
  2382   int  _double_count;           // count double ops requiring more precision
  2383   int  _java_call_count;        // count non-inlined 'java' calls
  2384   int  _inner_loop_count;       // count loops which need alignment
  2385   VectorSet _visited;           // Visitation flags
  2386   Node_List _tests;             // Set of IfNodes & PCTableNodes
  2388   Final_Reshape_Counts() :
  2389     _call_count(0), _float_count(0), _double_count(0),
  2390     _java_call_count(0), _inner_loop_count(0),
  2391     _visited( Thread::current()->resource_area() ) { }
  2393   void inc_call_count  () { _call_count  ++; }
  2394   void inc_float_count () { _float_count ++; }
  2395   void inc_double_count() { _double_count++; }
  2396   void inc_java_call_count() { _java_call_count++; }
  2397   void inc_inner_loop_count() { _inner_loop_count++; }
  2399   int  get_call_count  () const { return _call_count  ; }
  2400   int  get_float_count () const { return _float_count ; }
  2401   int  get_double_count() const { return _double_count; }
  2402   int  get_java_call_count() const { return _java_call_count; }
  2403   int  get_inner_loop_count() const { return _inner_loop_count; }
  2404 };
  2406 #ifdef ASSERT
  2407 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
  2408   ciInstanceKlass *k = tp->klass()->as_instance_klass();
  2409   // Make sure the offset goes inside the instance layout.
  2410   return k->contains_field_offset(tp->offset());
  2411   // Note that OffsetBot and OffsetTop are very negative.
  2413 #endif
  2415 // Eliminate trivially redundant StoreCMs and accumulate their
  2416 // precedence edges.
  2417 void Compile::eliminate_redundant_card_marks(Node* n) {
  2418   assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
  2419   if (n->in(MemNode::Address)->outcnt() > 1) {
  2420     // There are multiple users of the same address so it might be
  2421     // possible to eliminate some of the StoreCMs
  2422     Node* mem = n->in(MemNode::Memory);
  2423     Node* adr = n->in(MemNode::Address);
  2424     Node* val = n->in(MemNode::ValueIn);
  2425     Node* prev = n;
  2426     bool done = false;
  2427     // Walk the chain of StoreCMs eliminating ones that match.  As
  2428     // long as it's a chain of single users then the optimization is
  2429     // safe.  Eliminating partially redundant StoreCMs would require
  2430     // cloning copies down the other paths.
  2431     while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
  2432       if (adr == mem->in(MemNode::Address) &&
  2433           val == mem->in(MemNode::ValueIn)) {
  2434         // redundant StoreCM
  2435         if (mem->req() > MemNode::OopStore) {
  2436           // Hasn't been processed by this code yet.
  2437           n->add_prec(mem->in(MemNode::OopStore));
  2438         } else {
  2439           // Already converted to precedence edge
  2440           for (uint i = mem->req(); i < mem->len(); i++) {
  2441             // Accumulate any precedence edges
  2442             if (mem->in(i) != NULL) {
  2443               n->add_prec(mem->in(i));
  2446           // Everything above this point has been processed.
  2447           done = true;
  2449         // Eliminate the previous StoreCM
  2450         prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
  2451         assert(mem->outcnt() == 0, "should be dead");
  2452         mem->disconnect_inputs(NULL, this);
  2453       } else {
  2454         prev = mem;
  2456       mem = prev->in(MemNode::Memory);
  2461 //------------------------------final_graph_reshaping_impl----------------------
  2462 // Implement items 1-5 from final_graph_reshaping below.
  2463 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
  2465   if ( n->outcnt() == 0 ) return; // dead node
  2466   uint nop = n->Opcode();
  2468   // Check for 2-input instruction with "last use" on right input.
  2469   // Swap to left input.  Implements item (2).
  2470   if( n->req() == 3 &&          // two-input instruction
  2471       n->in(1)->outcnt() > 1 && // left use is NOT a last use
  2472       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
  2473       n->in(2)->outcnt() == 1 &&// right use IS a last use
  2474       !n->in(2)->is_Con() ) {   // right use is not a constant
  2475     // Check for commutative opcode
  2476     switch( nop ) {
  2477     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
  2478     case Op_MaxI:  case Op_MinI:
  2479     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
  2480     case Op_AndL:  case Op_XorL:  case Op_OrL:
  2481     case Op_AndI:  case Op_XorI:  case Op_OrI: {
  2482       // Move "last use" input to left by swapping inputs
  2483       n->swap_edges(1, 2);
  2484       break;
  2486     default:
  2487       break;
  2491 #ifdef ASSERT
  2492   if( n->is_Mem() ) {
  2493     int alias_idx = get_alias_index(n->as_Mem()->adr_type());
  2494     assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
  2495             // oop will be recorded in oop map if load crosses safepoint
  2496             n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
  2497                              LoadNode::is_immutable_value(n->in(MemNode::Address))),
  2498             "raw memory operations should have control edge");
  2500 #endif
  2501   // Count FPU ops and common calls, implements item (3)
  2502   switch( nop ) {
  2503   // Count all float operations that may use FPU
  2504   case Op_AddF:
  2505   case Op_SubF:
  2506   case Op_MulF:
  2507   case Op_DivF:
  2508   case Op_NegF:
  2509   case Op_ModF:
  2510   case Op_ConvI2F:
  2511   case Op_ConF:
  2512   case Op_CmpF:
  2513   case Op_CmpF3:
  2514   // case Op_ConvL2F: // longs are split into 32-bit halves
  2515     frc.inc_float_count();
  2516     break;
  2518   case Op_ConvF2D:
  2519   case Op_ConvD2F:
  2520     frc.inc_float_count();
  2521     frc.inc_double_count();
  2522     break;
  2524   // Count all double operations that may use FPU
  2525   case Op_AddD:
  2526   case Op_SubD:
  2527   case Op_MulD:
  2528   case Op_DivD:
  2529   case Op_NegD:
  2530   case Op_ModD:
  2531   case Op_ConvI2D:
  2532   case Op_ConvD2I:
  2533   // case Op_ConvL2D: // handled by leaf call
  2534   // case Op_ConvD2L: // handled by leaf call
  2535   case Op_ConD:
  2536   case Op_CmpD:
  2537   case Op_CmpD3:
  2538     frc.inc_double_count();
  2539     break;
  2540   case Op_Opaque1:              // Remove Opaque Nodes before matching
  2541   case Op_Opaque2:              // Remove Opaque Nodes before matching
  2542     n->subsume_by(n->in(1), this);
  2543     break;
  2544   case Op_CallStaticJava:
  2545   case Op_CallJava:
  2546   case Op_CallDynamicJava:
  2547     frc.inc_java_call_count(); // Count java call site;
  2548   case Op_CallRuntime:
  2549   case Op_CallLeaf:
  2550   case Op_CallLeafNoFP: {
  2551     assert( n->is_Call(), "" );
  2552     CallNode *call = n->as_Call();
  2553     // Count call sites where the FP mode bit would have to be flipped.
  2554     // Do not count uncommon runtime calls:
  2555     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
  2556     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
  2557     if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
  2558       frc.inc_call_count();   // Count the call site
  2559     } else {                  // See if uncommon argument is shared
  2560       Node *n = call->in(TypeFunc::Parms);
  2561       int nop = n->Opcode();
  2562       // Clone shared simple arguments to uncommon calls, item (1).
  2563       if( n->outcnt() > 1 &&
  2564           !n->is_Proj() &&
  2565           nop != Op_CreateEx &&
  2566           nop != Op_CheckCastPP &&
  2567           nop != Op_DecodeN &&
  2568           nop != Op_DecodeNKlass &&
  2569           !n->is_Mem() ) {
  2570         Node *x = n->clone();
  2571         call->set_req( TypeFunc::Parms, x );
  2574     break;
  2577   case Op_StoreD:
  2578   case Op_LoadD:
  2579   case Op_LoadD_unaligned:
  2580     frc.inc_double_count();
  2581     goto handle_mem;
  2582   case Op_StoreF:
  2583   case Op_LoadF:
  2584     frc.inc_float_count();
  2585     goto handle_mem;
  2587   case Op_StoreCM:
  2589       // Convert OopStore dependence into precedence edge
  2590       Node* prec = n->in(MemNode::OopStore);
  2591       n->del_req(MemNode::OopStore);
  2592       n->add_prec(prec);
  2593       eliminate_redundant_card_marks(n);
  2596     // fall through
  2598   case Op_StoreB:
  2599   case Op_StoreC:
  2600   case Op_StorePConditional:
  2601   case Op_StoreI:
  2602   case Op_StoreL:
  2603   case Op_StoreIConditional:
  2604   case Op_StoreLConditional:
  2605   case Op_CompareAndSwapI:
  2606   case Op_CompareAndSwapL:
  2607   case Op_CompareAndSwapP:
  2608   case Op_CompareAndSwapN:
  2609   case Op_GetAndAddI:
  2610   case Op_GetAndAddL:
  2611   case Op_GetAndSetI:
  2612   case Op_GetAndSetL:
  2613   case Op_GetAndSetP:
  2614   case Op_GetAndSetN:
  2615   case Op_StoreP:
  2616   case Op_StoreN:
  2617   case Op_StoreNKlass:
  2618   case Op_LoadB:
  2619   case Op_LoadUB:
  2620   case Op_LoadUS:
  2621   case Op_LoadI:
  2622   case Op_LoadKlass:
  2623   case Op_LoadNKlass:
  2624   case Op_LoadL:
  2625   case Op_LoadL_unaligned:
  2626   case Op_LoadPLocked:
  2627   case Op_LoadP:
  2628   case Op_LoadN:
  2629   case Op_LoadRange:
  2630   case Op_LoadS: {
  2631   handle_mem:
  2632 #ifdef ASSERT
  2633     if( VerifyOptoOopOffsets ) {
  2634       assert( n->is_Mem(), "" );
  2635       MemNode *mem  = (MemNode*)n;
  2636       // Check to see if address types have grounded out somehow.
  2637       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
  2638       assert( !tp || oop_offset_is_sane(tp), "" );
  2640 #endif
  2641     break;
  2644   case Op_AddP: {               // Assert sane base pointers
  2645     Node *addp = n->in(AddPNode::Address);
  2646     assert( !addp->is_AddP() ||
  2647             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
  2648             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
  2649             "Base pointers must match" );
  2650 #ifdef _LP64
  2651     if ((UseCompressedOops || UseCompressedClassPointers) &&
  2652         addp->Opcode() == Op_ConP &&
  2653         addp == n->in(AddPNode::Base) &&
  2654         n->in(AddPNode::Offset)->is_Con()) {
  2655       // Use addressing with narrow klass to load with offset on x86.
  2656       // On sparc loading 32-bits constant and decoding it have less
  2657       // instructions (4) then load 64-bits constant (7).
  2658       // Do this transformation here since IGVN will convert ConN back to ConP.
  2659       const Type* t = addp->bottom_type();
  2660       if (t->isa_oopptr() || t->isa_klassptr()) {
  2661         Node* nn = NULL;
  2663         int op = t->isa_oopptr() ? Op_ConN : Op_ConNKlass;
  2665         // Look for existing ConN node of the same exact type.
  2666         Node* r  = root();
  2667         uint cnt = r->outcnt();
  2668         for (uint i = 0; i < cnt; i++) {
  2669           Node* m = r->raw_out(i);
  2670           if (m!= NULL && m->Opcode() == op &&
  2671               m->bottom_type()->make_ptr() == t) {
  2672             nn = m;
  2673             break;
  2676         if (nn != NULL) {
  2677           // Decode a narrow oop to match address
  2678           // [R12 + narrow_oop_reg<<3 + offset]
  2679           if (t->isa_oopptr()) {
  2680             nn = new (this) DecodeNNode(nn, t);
  2681           } else {
  2682             nn = new (this) DecodeNKlassNode(nn, t);
  2684           n->set_req(AddPNode::Base, nn);
  2685           n->set_req(AddPNode::Address, nn);
  2686           if (addp->outcnt() == 0) {
  2687             addp->disconnect_inputs(NULL, this);
  2692 #endif
  2693     break;
  2696 #ifdef _LP64
  2697   case Op_CastPP:
  2698     if (n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
  2699       Node* in1 = n->in(1);
  2700       const Type* t = n->bottom_type();
  2701       Node* new_in1 = in1->clone();
  2702       new_in1->as_DecodeN()->set_type(t);
  2704       if (!Matcher::narrow_oop_use_complex_address()) {
  2705         //
  2706         // x86, ARM and friends can handle 2 adds in addressing mode
  2707         // and Matcher can fold a DecodeN node into address by using
  2708         // a narrow oop directly and do implicit NULL check in address:
  2709         //
  2710         // [R12 + narrow_oop_reg<<3 + offset]
  2711         // NullCheck narrow_oop_reg
  2712         //
  2713         // On other platforms (Sparc) we have to keep new DecodeN node and
  2714         // use it to do implicit NULL check in address:
  2715         //
  2716         // decode_not_null narrow_oop_reg, base_reg
  2717         // [base_reg + offset]
  2718         // NullCheck base_reg
  2719         //
  2720         // Pin the new DecodeN node to non-null path on these platform (Sparc)
  2721         // to keep the information to which NULL check the new DecodeN node
  2722         // corresponds to use it as value in implicit_null_check().
  2723         //
  2724         new_in1->set_req(0, n->in(0));
  2727       n->subsume_by(new_in1, this);
  2728       if (in1->outcnt() == 0) {
  2729         in1->disconnect_inputs(NULL, this);
  2732     break;
  2734   case Op_CmpP:
  2735     // Do this transformation here to preserve CmpPNode::sub() and
  2736     // other TypePtr related Ideal optimizations (for example, ptr nullness).
  2737     if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
  2738       Node* in1 = n->in(1);
  2739       Node* in2 = n->in(2);
  2740       if (!in1->is_DecodeNarrowPtr()) {
  2741         in2 = in1;
  2742         in1 = n->in(2);
  2744       assert(in1->is_DecodeNarrowPtr(), "sanity");
  2746       Node* new_in2 = NULL;
  2747       if (in2->is_DecodeNarrowPtr()) {
  2748         assert(in2->Opcode() == in1->Opcode(), "must be same node type");
  2749         new_in2 = in2->in(1);
  2750       } else if (in2->Opcode() == Op_ConP) {
  2751         const Type* t = in2->bottom_type();
  2752         if (t == TypePtr::NULL_PTR) {
  2753           assert(in1->is_DecodeN(), "compare klass to null?");
  2754           // Don't convert CmpP null check into CmpN if compressed
  2755           // oops implicit null check is not generated.
  2756           // This will allow to generate normal oop implicit null check.
  2757           if (Matcher::gen_narrow_oop_implicit_null_checks())
  2758             new_in2 = ConNode::make(this, TypeNarrowOop::NULL_PTR);
  2759           //
  2760           // This transformation together with CastPP transformation above
  2761           // will generated code for implicit NULL checks for compressed oops.
  2762           //
  2763           // The original code after Optimize()
  2764           //
  2765           //    LoadN memory, narrow_oop_reg
  2766           //    decode narrow_oop_reg, base_reg
  2767           //    CmpP base_reg, NULL
  2768           //    CastPP base_reg // NotNull
  2769           //    Load [base_reg + offset], val_reg
  2770           //
  2771           // after these transformations will be
  2772           //
  2773           //    LoadN memory, narrow_oop_reg
  2774           //    CmpN narrow_oop_reg, NULL
  2775           //    decode_not_null narrow_oop_reg, base_reg
  2776           //    Load [base_reg + offset], val_reg
  2777           //
  2778           // and the uncommon path (== NULL) will use narrow_oop_reg directly
  2779           // since narrow oops can be used in debug info now (see the code in
  2780           // final_graph_reshaping_walk()).
  2781           //
  2782           // At the end the code will be matched to
  2783           // on x86:
  2784           //
  2785           //    Load_narrow_oop memory, narrow_oop_reg
  2786           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
  2787           //    NullCheck narrow_oop_reg
  2788           //
  2789           // and on sparc:
  2790           //
  2791           //    Load_narrow_oop memory, narrow_oop_reg
  2792           //    decode_not_null narrow_oop_reg, base_reg
  2793           //    Load [base_reg + offset], val_reg
  2794           //    NullCheck base_reg
  2795           //
  2796         } else if (t->isa_oopptr()) {
  2797           new_in2 = ConNode::make(this, t->make_narrowoop());
  2798         } else if (t->isa_klassptr()) {
  2799           new_in2 = ConNode::make(this, t->make_narrowklass());
  2802       if (new_in2 != NULL) {
  2803         Node* cmpN = new (this) CmpNNode(in1->in(1), new_in2);
  2804         n->subsume_by(cmpN, this);
  2805         if (in1->outcnt() == 0) {
  2806           in1->disconnect_inputs(NULL, this);
  2808         if (in2->outcnt() == 0) {
  2809           in2->disconnect_inputs(NULL, this);
  2813     break;
  2815   case Op_DecodeN:
  2816   case Op_DecodeNKlass:
  2817     assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
  2818     // DecodeN could be pinned when it can't be fold into
  2819     // an address expression, see the code for Op_CastPP above.
  2820     assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
  2821     break;
  2823   case Op_EncodeP:
  2824   case Op_EncodePKlass: {
  2825     Node* in1 = n->in(1);
  2826     if (in1->is_DecodeNarrowPtr()) {
  2827       n->subsume_by(in1->in(1), this);
  2828     } else if (in1->Opcode() == Op_ConP) {
  2829       const Type* t = in1->bottom_type();
  2830       if (t == TypePtr::NULL_PTR) {
  2831         assert(t->isa_oopptr(), "null klass?");
  2832         n->subsume_by(ConNode::make(this, TypeNarrowOop::NULL_PTR), this);
  2833       } else if (t->isa_oopptr()) {
  2834         n->subsume_by(ConNode::make(this, t->make_narrowoop()), this);
  2835       } else if (t->isa_klassptr()) {
  2836         n->subsume_by(ConNode::make(this, t->make_narrowklass()), this);
  2839     if (in1->outcnt() == 0) {
  2840       in1->disconnect_inputs(NULL, this);
  2842     break;
  2845   case Op_Proj: {
  2846     if (OptimizeStringConcat) {
  2847       ProjNode* p = n->as_Proj();
  2848       if (p->_is_io_use) {
  2849         // Separate projections were used for the exception path which
  2850         // are normally removed by a late inline.  If it wasn't inlined
  2851         // then they will hang around and should just be replaced with
  2852         // the original one.
  2853         Node* proj = NULL;
  2854         // Replace with just one
  2855         for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
  2856           Node *use = i.get();
  2857           if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
  2858             proj = use;
  2859             break;
  2862         assert(proj != NULL, "must be found");
  2863         p->subsume_by(proj, this);
  2866     break;
  2869   case Op_Phi:
  2870     if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
  2871       // The EncodeP optimization may create Phi with the same edges
  2872       // for all paths. It is not handled well by Register Allocator.
  2873       Node* unique_in = n->in(1);
  2874       assert(unique_in != NULL, "");
  2875       uint cnt = n->req();
  2876       for (uint i = 2; i < cnt; i++) {
  2877         Node* m = n->in(i);
  2878         assert(m != NULL, "");
  2879         if (unique_in != m)
  2880           unique_in = NULL;
  2882       if (unique_in != NULL) {
  2883         n->subsume_by(unique_in, this);
  2886     break;
  2888 #endif
  2890   case Op_ModI:
  2891     if (UseDivMod) {
  2892       // Check if a%b and a/b both exist
  2893       Node* d = n->find_similar(Op_DivI);
  2894       if (d) {
  2895         // Replace them with a fused divmod if supported
  2896         if (Matcher::has_match_rule(Op_DivModI)) {
  2897           DivModINode* divmod = DivModINode::make(this, n);
  2898           d->subsume_by(divmod->div_proj(), this);
  2899           n->subsume_by(divmod->mod_proj(), this);
  2900         } else {
  2901           // replace a%b with a-((a/b)*b)
  2902           Node* mult = new (this) MulINode(d, d->in(2));
  2903           Node* sub  = new (this) SubINode(d->in(1), mult);
  2904           n->subsume_by(sub, this);
  2908     break;
  2910   case Op_ModL:
  2911     if (UseDivMod) {
  2912       // Check if a%b and a/b both exist
  2913       Node* d = n->find_similar(Op_DivL);
  2914       if (d) {
  2915         // Replace them with a fused divmod if supported
  2916         if (Matcher::has_match_rule(Op_DivModL)) {
  2917           DivModLNode* divmod = DivModLNode::make(this, n);
  2918           d->subsume_by(divmod->div_proj(), this);
  2919           n->subsume_by(divmod->mod_proj(), this);
  2920         } else {
  2921           // replace a%b with a-((a/b)*b)
  2922           Node* mult = new (this) MulLNode(d, d->in(2));
  2923           Node* sub  = new (this) SubLNode(d->in(1), mult);
  2924           n->subsume_by(sub, this);
  2928     break;
  2930   case Op_LoadVector:
  2931   case Op_StoreVector:
  2932     break;
  2934   case Op_PackB:
  2935   case Op_PackS:
  2936   case Op_PackI:
  2937   case Op_PackF:
  2938   case Op_PackL:
  2939   case Op_PackD:
  2940     if (n->req()-1 > 2) {
  2941       // Replace many operand PackNodes with a binary tree for matching
  2942       PackNode* p = (PackNode*) n;
  2943       Node* btp = p->binary_tree_pack(this, 1, n->req());
  2944       n->subsume_by(btp, this);
  2946     break;
  2947   case Op_Loop:
  2948   case Op_CountedLoop:
  2949     if (n->as_Loop()->is_inner_loop()) {
  2950       frc.inc_inner_loop_count();
  2952     break;
  2953   case Op_LShiftI:
  2954   case Op_RShiftI:
  2955   case Op_URShiftI:
  2956   case Op_LShiftL:
  2957   case Op_RShiftL:
  2958   case Op_URShiftL:
  2959     if (Matcher::need_masked_shift_count) {
  2960       // The cpu's shift instructions don't restrict the count to the
  2961       // lower 5/6 bits. We need to do the masking ourselves.
  2962       Node* in2 = n->in(2);
  2963       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
  2964       const TypeInt* t = in2->find_int_type();
  2965       if (t != NULL && t->is_con()) {
  2966         juint shift = t->get_con();
  2967         if (shift > mask) { // Unsigned cmp
  2968           n->set_req(2, ConNode::make(this, TypeInt::make(shift & mask)));
  2970       } else {
  2971         if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
  2972           Node* shift = new (this) AndINode(in2, ConNode::make(this, TypeInt::make(mask)));
  2973           n->set_req(2, shift);
  2976       if (in2->outcnt() == 0) { // Remove dead node
  2977         in2->disconnect_inputs(NULL, this);
  2980     break;
  2981   case Op_MemBarStoreStore:
  2982   case Op_MemBarRelease:
  2983     // Break the link with AllocateNode: it is no longer useful and
  2984     // confuses register allocation.
  2985     if (n->req() > MemBarNode::Precedent) {
  2986       n->set_req(MemBarNode::Precedent, top());
  2988     break;
  2989   default:
  2990     assert( !n->is_Call(), "" );
  2991     assert( !n->is_Mem(), "" );
  2992     break;
  2995   // Collect CFG split points
  2996   if (n->is_MultiBranch())
  2997     frc._tests.push(n);
  3000 //------------------------------final_graph_reshaping_walk---------------------
  3001 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
  3002 // requires that the walk visits a node's inputs before visiting the node.
  3003 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
  3004   ResourceArea *area = Thread::current()->resource_area();
  3005   Unique_Node_List sfpt(area);
  3007   frc._visited.set(root->_idx); // first, mark node as visited
  3008   uint cnt = root->req();
  3009   Node *n = root;
  3010   uint  i = 0;
  3011   while (true) {
  3012     if (i < cnt) {
  3013       // Place all non-visited non-null inputs onto stack
  3014       Node* m = n->in(i);
  3015       ++i;
  3016       if (m != NULL && !frc._visited.test_set(m->_idx)) {
  3017         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL)
  3018           sfpt.push(m);
  3019         cnt = m->req();
  3020         nstack.push(n, i); // put on stack parent and next input's index
  3021         n = m;
  3022         i = 0;
  3024     } else {
  3025       // Now do post-visit work
  3026       final_graph_reshaping_impl( n, frc );
  3027       if (nstack.is_empty())
  3028         break;             // finished
  3029       n = nstack.node();   // Get node from stack
  3030       cnt = n->req();
  3031       i = nstack.index();
  3032       nstack.pop();        // Shift to the next node on stack
  3036   // Skip next transformation if compressed oops are not used.
  3037   if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
  3038       (!UseCompressedOops && !UseCompressedClassPointers))
  3039     return;
  3041   // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
  3042   // It could be done for an uncommon traps or any safepoints/calls
  3043   // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
  3044   while (sfpt.size() > 0) {
  3045     n = sfpt.pop();
  3046     JVMState *jvms = n->as_SafePoint()->jvms();
  3047     assert(jvms != NULL, "sanity");
  3048     int start = jvms->debug_start();
  3049     int end   = n->req();
  3050     bool is_uncommon = (n->is_CallStaticJava() &&
  3051                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
  3052     for (int j = start; j < end; j++) {
  3053       Node* in = n->in(j);
  3054       if (in->is_DecodeNarrowPtr()) {
  3055         bool safe_to_skip = true;
  3056         if (!is_uncommon ) {
  3057           // Is it safe to skip?
  3058           for (uint i = 0; i < in->outcnt(); i++) {
  3059             Node* u = in->raw_out(i);
  3060             if (!u->is_SafePoint() ||
  3061                  u->is_Call() && u->as_Call()->has_non_debug_use(n)) {
  3062               safe_to_skip = false;
  3066         if (safe_to_skip) {
  3067           n->set_req(j, in->in(1));
  3069         if (in->outcnt() == 0) {
  3070           in->disconnect_inputs(NULL, this);
  3077 //------------------------------final_graph_reshaping--------------------------
  3078 // Final Graph Reshaping.
  3079 //
  3080 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
  3081 //     and not commoned up and forced early.  Must come after regular
  3082 //     optimizations to avoid GVN undoing the cloning.  Clone constant
  3083 //     inputs to Loop Phis; these will be split by the allocator anyways.
  3084 //     Remove Opaque nodes.
  3085 // (2) Move last-uses by commutative operations to the left input to encourage
  3086 //     Intel update-in-place two-address operations and better register usage
  3087 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
  3088 //     calls canonicalizing them back.
  3089 // (3) Count the number of double-precision FP ops, single-precision FP ops
  3090 //     and call sites.  On Intel, we can get correct rounding either by
  3091 //     forcing singles to memory (requires extra stores and loads after each
  3092 //     FP bytecode) or we can set a rounding mode bit (requires setting and
  3093 //     clearing the mode bit around call sites).  The mode bit is only used
  3094 //     if the relative frequency of single FP ops to calls is low enough.
  3095 //     This is a key transform for SPEC mpeg_audio.
  3096 // (4) Detect infinite loops; blobs of code reachable from above but not
  3097 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
  3098 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
  3099 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
  3100 //     Detection is by looking for IfNodes where only 1 projection is
  3101 //     reachable from below or CatchNodes missing some targets.
  3102 // (5) Assert for insane oop offsets in debug mode.
  3104 bool Compile::final_graph_reshaping() {
  3105   // an infinite loop may have been eliminated by the optimizer,
  3106   // in which case the graph will be empty.
  3107   if (root()->req() == 1) {
  3108     record_method_not_compilable("trivial infinite loop");
  3109     return true;
  3112   // Expensive nodes have their control input set to prevent the GVN
  3113   // from freely commoning them. There's no GVN beyond this point so
  3114   // no need to keep the control input. We want the expensive nodes to
  3115   // be freely moved to the least frequent code path by gcm.
  3116   assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
  3117   for (int i = 0; i < expensive_count(); i++) {
  3118     _expensive_nodes->at(i)->set_req(0, NULL);
  3121   Final_Reshape_Counts frc;
  3123   // Visit everybody reachable!
  3124   // Allocate stack of size C->unique()/2 to avoid frequent realloc
  3125   Node_Stack nstack(unique() >> 1);
  3126   final_graph_reshaping_walk(nstack, root(), frc);
  3128   // Check for unreachable (from below) code (i.e., infinite loops).
  3129   for( uint i = 0; i < frc._tests.size(); i++ ) {
  3130     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
  3131     // Get number of CFG targets.
  3132     // Note that PCTables include exception targets after calls.
  3133     uint required_outcnt = n->required_outcnt();
  3134     if (n->outcnt() != required_outcnt) {
  3135       // Check for a few special cases.  Rethrow Nodes never take the
  3136       // 'fall-thru' path, so expected kids is 1 less.
  3137       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
  3138         if (n->in(0)->in(0)->is_Call()) {
  3139           CallNode *call = n->in(0)->in(0)->as_Call();
  3140           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
  3141             required_outcnt--;      // Rethrow always has 1 less kid
  3142           } else if (call->req() > TypeFunc::Parms &&
  3143                      call->is_CallDynamicJava()) {
  3144             // Check for null receiver. In such case, the optimizer has
  3145             // detected that the virtual call will always result in a null
  3146             // pointer exception. The fall-through projection of this CatchNode
  3147             // will not be populated.
  3148             Node *arg0 = call->in(TypeFunc::Parms);
  3149             if (arg0->is_Type() &&
  3150                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
  3151               required_outcnt--;
  3153           } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
  3154                      call->req() > TypeFunc::Parms+1 &&
  3155                      call->is_CallStaticJava()) {
  3156             // Check for negative array length. In such case, the optimizer has
  3157             // detected that the allocation attempt will always result in an
  3158             // exception. There is no fall-through projection of this CatchNode .
  3159             Node *arg1 = call->in(TypeFunc::Parms+1);
  3160             if (arg1->is_Type() &&
  3161                 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
  3162               required_outcnt--;
  3167       // Recheck with a better notion of 'required_outcnt'
  3168       if (n->outcnt() != required_outcnt) {
  3169         record_method_not_compilable("malformed control flow");
  3170         return true;            // Not all targets reachable!
  3173     // Check that I actually visited all kids.  Unreached kids
  3174     // must be infinite loops.
  3175     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
  3176       if (!frc._visited.test(n->fast_out(j)->_idx)) {
  3177         record_method_not_compilable("infinite loop");
  3178         return true;            // Found unvisited kid; must be unreach
  3182   // If original bytecodes contained a mixture of floats and doubles
  3183   // check if the optimizer has made it homogenous, item (3).
  3184   if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
  3185       frc.get_float_count() > 32 &&
  3186       frc.get_double_count() == 0 &&
  3187       (10 * frc.get_call_count() < frc.get_float_count()) ) {
  3188     set_24_bit_selection_and_mode( false,  true );
  3191   set_java_calls(frc.get_java_call_count());
  3192   set_inner_loops(frc.get_inner_loop_count());
  3194   // No infinite loops, no reason to bail out.
  3195   return false;
  3198 //-----------------------------too_many_traps----------------------------------
  3199 // Report if there are too many traps at the current method and bci.
  3200 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
  3201 bool Compile::too_many_traps(ciMethod* method,
  3202                              int bci,
  3203                              Deoptimization::DeoptReason reason) {
  3204   ciMethodData* md = method->method_data();
  3205   if (md->is_empty()) {
  3206     // Assume the trap has not occurred, or that it occurred only
  3207     // because of a transient condition during start-up in the interpreter.
  3208     return false;
  3210   if (md->has_trap_at(bci, reason) != 0) {
  3211     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
  3212     // Also, if there are multiple reasons, or if there is no per-BCI record,
  3213     // assume the worst.
  3214     if (log())
  3215       log()->elem("observe trap='%s' count='%d'",
  3216                   Deoptimization::trap_reason_name(reason),
  3217                   md->trap_count(reason));
  3218     return true;
  3219   } else {
  3220     // Ignore method/bci and see if there have been too many globally.
  3221     return too_many_traps(reason, md);
  3225 // Less-accurate variant which does not require a method and bci.
  3226 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
  3227                              ciMethodData* logmd) {
  3228  if (trap_count(reason) >= (uint)PerMethodTrapLimit) {
  3229     // Too many traps globally.
  3230     // Note that we use cumulative trap_count, not just md->trap_count.
  3231     if (log()) {
  3232       int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
  3233       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
  3234                   Deoptimization::trap_reason_name(reason),
  3235                   mcount, trap_count(reason));
  3237     return true;
  3238   } else {
  3239     // The coast is clear.
  3240     return false;
  3244 //--------------------------too_many_recompiles--------------------------------
  3245 // Report if there are too many recompiles at the current method and bci.
  3246 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
  3247 // Is not eager to return true, since this will cause the compiler to use
  3248 // Action_none for a trap point, to avoid too many recompilations.
  3249 bool Compile::too_many_recompiles(ciMethod* method,
  3250                                   int bci,
  3251                                   Deoptimization::DeoptReason reason) {
  3252   ciMethodData* md = method->method_data();
  3253   if (md->is_empty()) {
  3254     // Assume the trap has not occurred, or that it occurred only
  3255     // because of a transient condition during start-up in the interpreter.
  3256     return false;
  3258   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
  3259   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
  3260   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
  3261   Deoptimization::DeoptReason per_bc_reason
  3262     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
  3263   if ((per_bc_reason == Deoptimization::Reason_none
  3264        || md->has_trap_at(bci, reason) != 0)
  3265       // The trap frequency measure we care about is the recompile count:
  3266       && md->trap_recompiled_at(bci)
  3267       && md->overflow_recompile_count() >= bc_cutoff) {
  3268     // Do not emit a trap here if it has already caused recompilations.
  3269     // Also, if there are multiple reasons, or if there is no per-BCI record,
  3270     // assume the worst.
  3271     if (log())
  3272       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
  3273                   Deoptimization::trap_reason_name(reason),
  3274                   md->trap_count(reason),
  3275                   md->overflow_recompile_count());
  3276     return true;
  3277   } else if (trap_count(reason) != 0
  3278              && decompile_count() >= m_cutoff) {
  3279     // Too many recompiles globally, and we have seen this sort of trap.
  3280     // Use cumulative decompile_count, not just md->decompile_count.
  3281     if (log())
  3282       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
  3283                   Deoptimization::trap_reason_name(reason),
  3284                   md->trap_count(reason), trap_count(reason),
  3285                   md->decompile_count(), decompile_count());
  3286     return true;
  3287   } else {
  3288     // The coast is clear.
  3289     return false;
  3294 #ifndef PRODUCT
  3295 //------------------------------verify_graph_edges---------------------------
  3296 // Walk the Graph and verify that there is a one-to-one correspondence
  3297 // between Use-Def edges and Def-Use edges in the graph.
  3298 void Compile::verify_graph_edges(bool no_dead_code) {
  3299   if (VerifyGraphEdges) {
  3300     ResourceArea *area = Thread::current()->resource_area();
  3301     Unique_Node_List visited(area);
  3302     // Call recursive graph walk to check edges
  3303     _root->verify_edges(visited);
  3304     if (no_dead_code) {
  3305       // Now make sure that no visited node is used by an unvisited node.
  3306       bool dead_nodes = 0;
  3307       Unique_Node_List checked(area);
  3308       while (visited.size() > 0) {
  3309         Node* n = visited.pop();
  3310         checked.push(n);
  3311         for (uint i = 0; i < n->outcnt(); i++) {
  3312           Node* use = n->raw_out(i);
  3313           if (checked.member(use))  continue;  // already checked
  3314           if (visited.member(use))  continue;  // already in the graph
  3315           if (use->is_Con())        continue;  // a dead ConNode is OK
  3316           // At this point, we have found a dead node which is DU-reachable.
  3317           if (dead_nodes++ == 0)
  3318             tty->print_cr("*** Dead nodes reachable via DU edges:");
  3319           use->dump(2);
  3320           tty->print_cr("---");
  3321           checked.push(use);  // No repeats; pretend it is now checked.
  3324       assert(dead_nodes == 0, "using nodes must be reachable from root");
  3328 #endif
  3330 // The Compile object keeps track of failure reasons separately from the ciEnv.
  3331 // This is required because there is not quite a 1-1 relation between the
  3332 // ciEnv and its compilation task and the Compile object.  Note that one
  3333 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
  3334 // to backtrack and retry without subsuming loads.  Other than this backtracking
  3335 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
  3336 // by the logic in C2Compiler.
  3337 void Compile::record_failure(const char* reason) {
  3338   if (log() != NULL) {
  3339     log()->elem("failure reason='%s' phase='compile'", reason);
  3341   if (_failure_reason == NULL) {
  3342     // Record the first failure reason.
  3343     _failure_reason = reason;
  3346   EventCompilerFailure event;
  3347   if (event.should_commit()) {
  3348     event.set_compileID(Compile::compile_id());
  3349     event.set_failure(reason);
  3350     event.commit();
  3353   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
  3354     C->print_method(PHASE_FAILURE);
  3356   _root = NULL;  // flush the graph, too
  3359 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator, bool dolog)
  3360   : TraceTime(NULL, accumulator, false NOT_PRODUCT( || TimeCompiler ), false),
  3361     _phase_name(name), _dolog(dolog)
  3363   if (dolog) {
  3364     C = Compile::current();
  3365     _log = C->log();
  3366   } else {
  3367     C = NULL;
  3368     _log = NULL;
  3370   if (_log != NULL) {
  3371     _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
  3372     _log->stamp();
  3373     _log->end_head();
  3377 Compile::TracePhase::~TracePhase() {
  3379   C = Compile::current();
  3380   if (_dolog) {
  3381     _log = C->log();
  3382   } else {
  3383     _log = NULL;
  3386 #ifdef ASSERT
  3387   if (PrintIdealNodeCount) {
  3388     tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
  3389                   _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
  3392   if (VerifyIdealNodeCount) {
  3393     Compile::current()->print_missing_nodes();
  3395 #endif
  3397   if (_log != NULL) {
  3398     _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
  3402 //=============================================================================
  3403 // Two Constant's are equal when the type and the value are equal.
  3404 bool Compile::Constant::operator==(const Constant& other) {
  3405   if (type()          != other.type()         )  return false;
  3406   if (can_be_reused() != other.can_be_reused())  return false;
  3407   // For floating point values we compare the bit pattern.
  3408   switch (type()) {
  3409   case T_FLOAT:   return (_v._value.i == other._v._value.i);
  3410   case T_LONG:
  3411   case T_DOUBLE:  return (_v._value.j == other._v._value.j);
  3412   case T_OBJECT:
  3413   case T_ADDRESS: return (_v._value.l == other._v._value.l);
  3414   case T_VOID:    return (_v._value.l == other._v._value.l);  // jump-table entries
  3415   case T_METADATA: return (_v._metadata == other._v._metadata);
  3416   default: ShouldNotReachHere();
  3418   return false;
  3421 static int type_to_size_in_bytes(BasicType t) {
  3422   switch (t) {
  3423   case T_LONG:    return sizeof(jlong  );
  3424   case T_FLOAT:   return sizeof(jfloat );
  3425   case T_DOUBLE:  return sizeof(jdouble);
  3426   case T_METADATA: return sizeof(Metadata*);
  3427     // We use T_VOID as marker for jump-table entries (labels) which
  3428     // need an internal word relocation.
  3429   case T_VOID:
  3430   case T_ADDRESS:
  3431   case T_OBJECT:  return sizeof(jobject);
  3434   ShouldNotReachHere();
  3435   return -1;
  3438 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
  3439   // sort descending
  3440   if (a->freq() > b->freq())  return -1;
  3441   if (a->freq() < b->freq())  return  1;
  3442   return 0;
  3445 void Compile::ConstantTable::calculate_offsets_and_size() {
  3446   // First, sort the array by frequencies.
  3447   _constants.sort(qsort_comparator);
  3449 #ifdef ASSERT
  3450   // Make sure all jump-table entries were sorted to the end of the
  3451   // array (they have a negative frequency).
  3452   bool found_void = false;
  3453   for (int i = 0; i < _constants.length(); i++) {
  3454     Constant con = _constants.at(i);
  3455     if (con.type() == T_VOID)
  3456       found_void = true;  // jump-tables
  3457     else
  3458       assert(!found_void, "wrong sorting");
  3460 #endif
  3462   int offset = 0;
  3463   for (int i = 0; i < _constants.length(); i++) {
  3464     Constant* con = _constants.adr_at(i);
  3466     // Align offset for type.
  3467     int typesize = type_to_size_in_bytes(con->type());
  3468     offset = align_size_up(offset, typesize);
  3469     con->set_offset(offset);   // set constant's offset
  3471     if (con->type() == T_VOID) {
  3472       MachConstantNode* n = (MachConstantNode*) con->get_jobject();
  3473       offset = offset + typesize * n->outcnt();  // expand jump-table
  3474     } else {
  3475       offset = offset + typesize;
  3479   // Align size up to the next section start (which is insts; see
  3480   // CodeBuffer::align_at_start).
  3481   assert(_size == -1, "already set?");
  3482   _size = align_size_up(offset, CodeEntryAlignment);
  3485 void Compile::ConstantTable::emit(CodeBuffer& cb) {
  3486   MacroAssembler _masm(&cb);
  3487   for (int i = 0; i < _constants.length(); i++) {
  3488     Constant con = _constants.at(i);
  3489     address constant_addr;
  3490     switch (con.type()) {
  3491     case T_LONG:   constant_addr = _masm.long_constant(  con.get_jlong()  ); break;
  3492     case T_FLOAT:  constant_addr = _masm.float_constant( con.get_jfloat() ); break;
  3493     case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
  3494     case T_OBJECT: {
  3495       jobject obj = con.get_jobject();
  3496       int oop_index = _masm.oop_recorder()->find_index(obj);
  3497       constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
  3498       break;
  3500     case T_ADDRESS: {
  3501       address addr = (address) con.get_jobject();
  3502       constant_addr = _masm.address_constant(addr);
  3503       break;
  3505     // We use T_VOID as marker for jump-table entries (labels) which
  3506     // need an internal word relocation.
  3507     case T_VOID: {
  3508       MachConstantNode* n = (MachConstantNode*) con.get_jobject();
  3509       // Fill the jump-table with a dummy word.  The real value is
  3510       // filled in later in fill_jump_table.
  3511       address dummy = (address) n;
  3512       constant_addr = _masm.address_constant(dummy);
  3513       // Expand jump-table
  3514       for (uint i = 1; i < n->outcnt(); i++) {
  3515         address temp_addr = _masm.address_constant(dummy + i);
  3516         assert(temp_addr, "consts section too small");
  3518       break;
  3520     case T_METADATA: {
  3521       Metadata* obj = con.get_metadata();
  3522       int metadata_index = _masm.oop_recorder()->find_index(obj);
  3523       constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
  3524       break;
  3526     default: ShouldNotReachHere();
  3528     assert(constant_addr, "consts section too small");
  3529     assert((constant_addr - _masm.code()->consts()->start()) == con.offset(), err_msg_res("must be: %d == %d", constant_addr - _masm.code()->consts()->start(), con.offset()));
  3533 int Compile::ConstantTable::find_offset(Constant& con) const {
  3534   int idx = _constants.find(con);
  3535   assert(idx != -1, "constant must be in constant table");
  3536   int offset = _constants.at(idx).offset();
  3537   assert(offset != -1, "constant table not emitted yet?");
  3538   return offset;
  3541 void Compile::ConstantTable::add(Constant& con) {
  3542   if (con.can_be_reused()) {
  3543     int idx = _constants.find(con);
  3544     if (idx != -1 && _constants.at(idx).can_be_reused()) {
  3545       _constants.adr_at(idx)->inc_freq(con.freq());  // increase the frequency by the current value
  3546       return;
  3549   (void) _constants.append(con);
  3552 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
  3553   Block* b = Compile::current()->cfg()->get_block_for_node(n);
  3554   Constant con(type, value, b->_freq);
  3555   add(con);
  3556   return con;
  3559 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
  3560   Constant con(metadata);
  3561   add(con);
  3562   return con;
  3565 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
  3566   jvalue value;
  3567   BasicType type = oper->type()->basic_type();
  3568   switch (type) {
  3569   case T_LONG:    value.j = oper->constantL(); break;
  3570   case T_FLOAT:   value.f = oper->constantF(); break;
  3571   case T_DOUBLE:  value.d = oper->constantD(); break;
  3572   case T_OBJECT:
  3573   case T_ADDRESS: value.l = (jobject) oper->constant(); break;
  3574   case T_METADATA: return add((Metadata*)oper->constant()); break;
  3575   default: guarantee(false, err_msg_res("unhandled type: %s", type2name(type)));
  3577   return add(n, type, value);
  3580 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
  3581   jvalue value;
  3582   // We can use the node pointer here to identify the right jump-table
  3583   // as this method is called from Compile::Fill_buffer right before
  3584   // the MachNodes are emitted and the jump-table is filled (means the
  3585   // MachNode pointers do not change anymore).
  3586   value.l = (jobject) n;
  3587   Constant con(T_VOID, value, next_jump_table_freq(), false);  // Labels of a jump-table cannot be reused.
  3588   add(con);
  3589   return con;
  3592 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
  3593   // If called from Compile::scratch_emit_size do nothing.
  3594   if (Compile::current()->in_scratch_emit_size())  return;
  3596   assert(labels.is_nonempty(), "must be");
  3597   assert((uint) labels.length() == n->outcnt(), err_msg_res("must be equal: %d == %d", labels.length(), n->outcnt()));
  3599   // Since MachConstantNode::constant_offset() also contains
  3600   // table_base_offset() we need to subtract the table_base_offset()
  3601   // to get the plain offset into the constant table.
  3602   int offset = n->constant_offset() - table_base_offset();
  3604   MacroAssembler _masm(&cb);
  3605   address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
  3607   for (uint i = 0; i < n->outcnt(); i++) {
  3608     address* constant_addr = &jump_table_base[i];
  3609     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)));
  3610     *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
  3611     cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
  3615 void Compile::dump_inlining() {
  3616   if (print_inlining() || print_intrinsics()) {
  3617     // Print inlining message for candidates that we couldn't inline
  3618     // for lack of space or non constant receiver
  3619     for (int i = 0; i < _late_inlines.length(); i++) {
  3620       CallGenerator* cg = _late_inlines.at(i);
  3621       cg->print_inlining_late("live nodes > LiveNodeCountInliningCutoff");
  3623     Unique_Node_List useful;
  3624     useful.push(root());
  3625     for (uint next = 0; next < useful.size(); ++next) {
  3626       Node* n  = useful.at(next);
  3627       if (n->is_Call() && n->as_Call()->generator() != NULL && n->as_Call()->generator()->call_node() == n) {
  3628         CallNode* call = n->as_Call();
  3629         CallGenerator* cg = call->generator();
  3630         cg->print_inlining_late("receiver not constant");
  3632       uint max = n->len();
  3633       for ( uint i = 0; i < max; ++i ) {
  3634         Node *m = n->in(i);
  3635         if ( m == NULL ) continue;
  3636         useful.push(m);
  3639     for (int i = 0; i < _print_inlining_list->length(); i++) {
  3640       tty->print(_print_inlining_list->adr_at(i)->ss()->as_string());
  3645 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
  3646   if (n1->Opcode() < n2->Opcode())      return -1;
  3647   else if (n1->Opcode() > n2->Opcode()) return 1;
  3649   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()));
  3650   for (uint i = 1; i < n1->req(); i++) {
  3651     if (n1->in(i) < n2->in(i))      return -1;
  3652     else if (n1->in(i) > n2->in(i)) return 1;
  3655   return 0;
  3658 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
  3659   Node* n1 = *n1p;
  3660   Node* n2 = *n2p;
  3662   return cmp_expensive_nodes(n1, n2);
  3665 void Compile::sort_expensive_nodes() {
  3666   if (!expensive_nodes_sorted()) {
  3667     _expensive_nodes->sort(cmp_expensive_nodes);
  3671 bool Compile::expensive_nodes_sorted() const {
  3672   for (int i = 1; i < _expensive_nodes->length(); i++) {
  3673     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
  3674       return false;
  3677   return true;
  3680 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
  3681   if (_expensive_nodes->length() == 0) {
  3682     return false;
  3685   assert(OptimizeExpensiveOps, "optimization off?");
  3687   // Take this opportunity to remove dead nodes from the list
  3688   int j = 0;
  3689   for (int i = 0; i < _expensive_nodes->length(); i++) {
  3690     Node* n = _expensive_nodes->at(i);
  3691     if (!n->is_unreachable(igvn)) {
  3692       assert(n->is_expensive(), "should be expensive");
  3693       _expensive_nodes->at_put(j, n);
  3694       j++;
  3697   _expensive_nodes->trunc_to(j);
  3699   // Then sort the list so that similar nodes are next to each other
  3700   // and check for at least two nodes of identical kind with same data
  3701   // inputs.
  3702   sort_expensive_nodes();
  3704   for (int i = 0; i < _expensive_nodes->length()-1; i++) {
  3705     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
  3706       return true;
  3710   return false;
  3713 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
  3714   if (_expensive_nodes->length() == 0) {
  3715     return;
  3718   assert(OptimizeExpensiveOps, "optimization off?");
  3720   // Sort to bring similar nodes next to each other and clear the
  3721   // control input of nodes for which there's only a single copy.
  3722   sort_expensive_nodes();
  3724   int j = 0;
  3725   int identical = 0;
  3726   int i = 0;
  3727   for (; i < _expensive_nodes->length()-1; i++) {
  3728     assert(j <= i, "can't write beyond current index");
  3729     if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
  3730       identical++;
  3731       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3732       continue;
  3734     if (identical > 0) {
  3735       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3736       identical = 0;
  3737     } else {
  3738       Node* n = _expensive_nodes->at(i);
  3739       igvn.hash_delete(n);
  3740       n->set_req(0, NULL);
  3741       igvn.hash_insert(n);
  3744   if (identical > 0) {
  3745     _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3746   } else if (_expensive_nodes->length() >= 1) {
  3747     Node* n = _expensive_nodes->at(i);
  3748     igvn.hash_delete(n);
  3749     n->set_req(0, NULL);
  3750     igvn.hash_insert(n);
  3752   _expensive_nodes->trunc_to(j);
  3755 void Compile::add_expensive_node(Node * n) {
  3756   assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
  3757   assert(n->is_expensive(), "expensive nodes with non-null control here only");
  3758   assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
  3759   if (OptimizeExpensiveOps) {
  3760     _expensive_nodes->append(n);
  3761   } else {
  3762     // Clear control input and let IGVN optimize expensive nodes if
  3763     // OptimizeExpensiveOps is off.
  3764     n->set_req(0, NULL);
  3768 // Auxiliary method to support randomized stressing/fuzzing.
  3769 //
  3770 // This method can be called the arbitrary number of times, with current count
  3771 // as the argument. The logic allows selecting a single candidate from the
  3772 // running list of candidates as follows:
  3773 //    int count = 0;
  3774 //    Cand* selected = null;
  3775 //    while(cand = cand->next()) {
  3776 //      if (randomized_select(++count)) {
  3777 //        selected = cand;
  3778 //      }
  3779 //    }
  3780 //
  3781 // Including count equalizes the chances any candidate is "selected".
  3782 // This is useful when we don't have the complete list of candidates to choose
  3783 // from uniformly. In this case, we need to adjust the randomicity of the
  3784 // selection, or else we will end up biasing the selection towards the latter
  3785 // candidates.
  3786 //
  3787 // Quick back-envelope calculation shows that for the list of n candidates
  3788 // the equal probability for the candidate to persist as "best" can be
  3789 // achieved by replacing it with "next" k-th candidate with the probability
  3790 // of 1/k. It can be easily shown that by the end of the run, the
  3791 // probability for any candidate is converged to 1/n, thus giving the
  3792 // uniform distribution among all the candidates.
  3793 //
  3794 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
  3795 #define RANDOMIZED_DOMAIN_POW 29
  3796 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
  3797 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
  3798 bool Compile::randomized_select(int count) {
  3799   assert(count > 0, "only positive");
  3800   return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);

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