src/share/vm/opto/compile.cpp

Sat, 16 Mar 2013 07:39:14 -0700

author
morris
date
Sat, 16 Mar 2013 07:39:14 -0700
changeset 4760
96ef09c26978
parent 4730
b7c2c5b2572c
child 4889
cc32ccaaf47f
permissions
-rw-r--r--

8009166: [parfait] Null pointer deference in hotspot/src/share/vm/opto/type.cpp
Summary: add guarantee() to as_instance_type()
Reviewed-by: kvn, twisti

     1 /*
     2  * Copyright (c) 1997, 2012, 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 "utilities/copy.hpp"
    67 #ifdef TARGET_ARCH_MODEL_x86_32
    68 # include "adfiles/ad_x86_32.hpp"
    69 #endif
    70 #ifdef TARGET_ARCH_MODEL_x86_64
    71 # include "adfiles/ad_x86_64.hpp"
    72 #endif
    73 #ifdef TARGET_ARCH_MODEL_sparc
    74 # include "adfiles/ad_sparc.hpp"
    75 #endif
    76 #ifdef TARGET_ARCH_MODEL_zero
    77 # include "adfiles/ad_zero.hpp"
    78 #endif
    79 #ifdef TARGET_ARCH_MODEL_arm
    80 # include "adfiles/ad_arm.hpp"
    81 #endif
    82 #ifdef TARGET_ARCH_MODEL_ppc
    83 # include "adfiles/ad_ppc.hpp"
    84 #endif
    87 // -------------------- Compile::mach_constant_base_node -----------------------
    88 // Constant table base node singleton.
    89 MachConstantBaseNode* Compile::mach_constant_base_node() {
    90   if (_mach_constant_base_node == NULL) {
    91     _mach_constant_base_node = new (C) MachConstantBaseNode();
    92     _mach_constant_base_node->add_req(C->root());
    93   }
    94   return _mach_constant_base_node;
    95 }
    98 /// Support for intrinsics.
   100 // Return the index at which m must be inserted (or already exists).
   101 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
   102 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual) {
   103 #ifdef ASSERT
   104   for (int i = 1; i < _intrinsics->length(); i++) {
   105     CallGenerator* cg1 = _intrinsics->at(i-1);
   106     CallGenerator* cg2 = _intrinsics->at(i);
   107     assert(cg1->method() != cg2->method()
   108            ? cg1->method()     < cg2->method()
   109            : cg1->is_virtual() < cg2->is_virtual(),
   110            "compiler intrinsics list must stay sorted");
   111   }
   112 #endif
   113   // Binary search sorted list, in decreasing intervals [lo, hi].
   114   int lo = 0, hi = _intrinsics->length()-1;
   115   while (lo <= hi) {
   116     int mid = (uint)(hi + lo) / 2;
   117     ciMethod* mid_m = _intrinsics->at(mid)->method();
   118     if (m < mid_m) {
   119       hi = mid-1;
   120     } else if (m > mid_m) {
   121       lo = mid+1;
   122     } else {
   123       // look at minor sort key
   124       bool mid_virt = _intrinsics->at(mid)->is_virtual();
   125       if (is_virtual < mid_virt) {
   126         hi = mid-1;
   127       } else if (is_virtual > mid_virt) {
   128         lo = mid+1;
   129       } else {
   130         return mid;  // exact match
   131       }
   132     }
   133   }
   134   return lo;  // inexact match
   135 }
   137 void Compile::register_intrinsic(CallGenerator* cg) {
   138   if (_intrinsics == NULL) {
   139     _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
   140   }
   141   // This code is stolen from ciObjectFactory::insert.
   142   // Really, GrowableArray should have methods for
   143   // insert_at, remove_at, and binary_search.
   144   int len = _intrinsics->length();
   145   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual());
   146   if (index == len) {
   147     _intrinsics->append(cg);
   148   } else {
   149 #ifdef ASSERT
   150     CallGenerator* oldcg = _intrinsics->at(index);
   151     assert(oldcg->method() != cg->method() || oldcg->is_virtual() != cg->is_virtual(), "don't register twice");
   152 #endif
   153     _intrinsics->append(_intrinsics->at(len-1));
   154     int pos;
   155     for (pos = len-2; pos >= index; pos--) {
   156       _intrinsics->at_put(pos+1,_intrinsics->at(pos));
   157     }
   158     _intrinsics->at_put(index, cg);
   159   }
   160   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
   161 }
   163 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
   164   assert(m->is_loaded(), "don't try this on unloaded methods");
   165   if (_intrinsics != NULL) {
   166     int index = intrinsic_insertion_index(m, is_virtual);
   167     if (index < _intrinsics->length()
   168         && _intrinsics->at(index)->method() == m
   169         && _intrinsics->at(index)->is_virtual() == is_virtual) {
   170       return _intrinsics->at(index);
   171     }
   172   }
   173   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
   174   if (m->intrinsic_id() != vmIntrinsics::_none &&
   175       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
   176     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
   177     if (cg != NULL) {
   178       // Save it for next time:
   179       register_intrinsic(cg);
   180       return cg;
   181     } else {
   182       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
   183     }
   184   }
   185   return NULL;
   186 }
   188 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
   189 // in library_call.cpp.
   192 #ifndef PRODUCT
   193 // statistics gathering...
   195 juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
   196 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
   198 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
   199   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
   200   int oflags = _intrinsic_hist_flags[id];
   201   assert(flags != 0, "what happened?");
   202   if (is_virtual) {
   203     flags |= _intrinsic_virtual;
   204   }
   205   bool changed = (flags != oflags);
   206   if ((flags & _intrinsic_worked) != 0) {
   207     juint count = (_intrinsic_hist_count[id] += 1);
   208     if (count == 1) {
   209       changed = true;           // first time
   210     }
   211     // increment the overall count also:
   212     _intrinsic_hist_count[vmIntrinsics::_none] += 1;
   213   }
   214   if (changed) {
   215     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
   216       // Something changed about the intrinsic's virtuality.
   217       if ((flags & _intrinsic_virtual) != 0) {
   218         // This is the first use of this intrinsic as a virtual call.
   219         if (oflags != 0) {
   220           // We already saw it as a non-virtual, so note both cases.
   221           flags |= _intrinsic_both;
   222         }
   223       } else if ((oflags & _intrinsic_both) == 0) {
   224         // This is the first use of this intrinsic as a non-virtual
   225         flags |= _intrinsic_both;
   226       }
   227     }
   228     _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
   229   }
   230   // update the overall flags also:
   231   _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
   232   return changed;
   233 }
   235 static char* format_flags(int flags, char* buf) {
   236   buf[0] = 0;
   237   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
   238   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
   239   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
   240   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
   241   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
   242   if (buf[0] == 0)  strcat(buf, ",");
   243   assert(buf[0] == ',', "must be");
   244   return &buf[1];
   245 }
   247 void Compile::print_intrinsic_statistics() {
   248   char flagsbuf[100];
   249   ttyLocker ttyl;
   250   if (xtty != NULL)  xtty->head("statistics type='intrinsic'");
   251   tty->print_cr("Compiler intrinsic usage:");
   252   juint total = _intrinsic_hist_count[vmIntrinsics::_none];
   253   if (total == 0)  total = 1;  // avoid div0 in case of no successes
   254   #define PRINT_STAT_LINE(name, c, f) \
   255     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
   256   for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
   257     vmIntrinsics::ID id = (vmIntrinsics::ID) index;
   258     int   flags = _intrinsic_hist_flags[id];
   259     juint count = _intrinsic_hist_count[id];
   260     if ((flags | count) != 0) {
   261       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
   262     }
   263   }
   264   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
   265   if (xtty != NULL)  xtty->tail("statistics");
   266 }
   268 void Compile::print_statistics() {
   269   { ttyLocker ttyl;
   270     if (xtty != NULL)  xtty->head("statistics type='opto'");
   271     Parse::print_statistics();
   272     PhaseCCP::print_statistics();
   273     PhaseRegAlloc::print_statistics();
   274     Scheduling::print_statistics();
   275     PhasePeephole::print_statistics();
   276     PhaseIdealLoop::print_statistics();
   277     if (xtty != NULL)  xtty->tail("statistics");
   278   }
   279   if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
   280     // put this under its own <statistics> element.
   281     print_intrinsic_statistics();
   282   }
   283 }
   284 #endif //PRODUCT
   286 // Support for bundling info
   287 Bundle* Compile::node_bundling(const Node *n) {
   288   assert(valid_bundle_info(n), "oob");
   289   return &_node_bundling_base[n->_idx];
   290 }
   292 bool Compile::valid_bundle_info(const Node *n) {
   293   return (_node_bundling_limit > n->_idx);
   294 }
   297 void Compile::gvn_replace_by(Node* n, Node* nn) {
   298   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
   299     Node* use = n->last_out(i);
   300     bool is_in_table = initial_gvn()->hash_delete(use);
   301     uint uses_found = 0;
   302     for (uint j = 0; j < use->len(); j++) {
   303       if (use->in(j) == n) {
   304         if (j < use->req())
   305           use->set_req(j, nn);
   306         else
   307           use->set_prec(j, nn);
   308         uses_found++;
   309       }
   310     }
   311     if (is_in_table) {
   312       // reinsert into table
   313       initial_gvn()->hash_find_insert(use);
   314     }
   315     record_for_igvn(use);
   316     i -= uses_found;    // we deleted 1 or more copies of this edge
   317   }
   318 }
   321 static inline bool not_a_node(const Node* n) {
   322   if (n == NULL)                   return true;
   323   if (((intptr_t)n & 1) != 0)      return true;  // uninitialized, etc.
   324   if (*(address*)n == badAddress)  return true;  // kill by Node::destruct
   325   return false;
   326 }
   328 // Identify all nodes that are reachable from below, useful.
   329 // Use breadth-first pass that records state in a Unique_Node_List,
   330 // recursive traversal is slower.
   331 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
   332   int estimated_worklist_size = unique();
   333   useful.map( estimated_worklist_size, NULL );  // preallocate space
   335   // Initialize worklist
   336   if (root() != NULL)     { useful.push(root()); }
   337   // If 'top' is cached, declare it useful to preserve cached node
   338   if( cached_top_node() ) { useful.push(cached_top_node()); }
   340   // Push all useful nodes onto the list, breadthfirst
   341   for( uint next = 0; next < useful.size(); ++next ) {
   342     assert( next < unique(), "Unique useful nodes < total nodes");
   343     Node *n  = useful.at(next);
   344     uint max = n->len();
   345     for( uint i = 0; i < max; ++i ) {
   346       Node *m = n->in(i);
   347       if (not_a_node(m))  continue;
   348       useful.push(m);
   349     }
   350   }
   351 }
   353 // Update dead_node_list with any missing dead nodes using useful
   354 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
   355 void Compile::update_dead_node_list(Unique_Node_List &useful) {
   356   uint max_idx = unique();
   357   VectorSet& useful_node_set = useful.member_set();
   359   for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
   360     // If node with index node_idx is not in useful set,
   361     // mark it as dead in dead node list.
   362     if (! useful_node_set.test(node_idx) ) {
   363       record_dead_node(node_idx);
   364     }
   365   }
   366 }
   368 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
   369   int shift = 0;
   370   for (int i = 0; i < inlines->length(); i++) {
   371     CallGenerator* cg = inlines->at(i);
   372     CallNode* call = cg->call_node();
   373     if (shift > 0) {
   374       inlines->at_put(i-shift, cg);
   375     }
   376     if (!useful.member(call)) {
   377       shift++;
   378     }
   379   }
   380   inlines->trunc_to(inlines->length()-shift);
   381 }
   383 // Disconnect all useless nodes by disconnecting those at the boundary.
   384 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
   385   uint next = 0;
   386   while (next < useful.size()) {
   387     Node *n = useful.at(next++);
   388     // Use raw traversal of out edges since this code removes out edges
   389     int max = n->outcnt();
   390     for (int j = 0; j < max; ++j) {
   391       Node* child = n->raw_out(j);
   392       if (! useful.member(child)) {
   393         assert(!child->is_top() || child != top(),
   394                "If top is cached in Compile object it is in useful list");
   395         // Only need to remove this out-edge to the useless node
   396         n->raw_del_out(j);
   397         --j;
   398         --max;
   399       }
   400     }
   401     if (n->outcnt() == 1 && n->has_special_unique_user()) {
   402       record_for_igvn(n->unique_out());
   403     }
   404   }
   405   // Remove useless macro and predicate opaq nodes
   406   for (int i = C->macro_count()-1; i >= 0; i--) {
   407     Node* n = C->macro_node(i);
   408     if (!useful.member(n)) {
   409       remove_macro_node(n);
   410     }
   411   }
   412   // Remove useless expensive node
   413   for (int i = C->expensive_count()-1; i >= 0; i--) {
   414     Node* n = C->expensive_node(i);
   415     if (!useful.member(n)) {
   416       remove_expensive_node(n);
   417     }
   418   }
   419   // clean up the late inline lists
   420   remove_useless_late_inlines(&_string_late_inlines, useful);
   421   remove_useless_late_inlines(&_late_inlines, useful);
   422   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
   423 }
   425 //------------------------------frame_size_in_words-----------------------------
   426 // frame_slots in units of words
   427 int Compile::frame_size_in_words() const {
   428   // shift is 0 in LP32 and 1 in LP64
   429   const int shift = (LogBytesPerWord - LogBytesPerInt);
   430   int words = _frame_slots >> shift;
   431   assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
   432   return words;
   433 }
   435 // ============================================================================
   436 //------------------------------CompileWrapper---------------------------------
   437 class CompileWrapper : public StackObj {
   438   Compile *const _compile;
   439  public:
   440   CompileWrapper(Compile* compile);
   442   ~CompileWrapper();
   443 };
   445 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
   446   // the Compile* pointer is stored in the current ciEnv:
   447   ciEnv* env = compile->env();
   448   assert(env == ciEnv::current(), "must already be a ciEnv active");
   449   assert(env->compiler_data() == NULL, "compile already active?");
   450   env->set_compiler_data(compile);
   451   assert(compile == Compile::current(), "sanity");
   453   compile->set_type_dict(NULL);
   454   compile->set_type_hwm(NULL);
   455   compile->set_type_last_size(0);
   456   compile->set_last_tf(NULL, NULL);
   457   compile->set_indexSet_arena(NULL);
   458   compile->set_indexSet_free_block_list(NULL);
   459   compile->init_type_arena();
   460   Type::Initialize(compile);
   461   _compile->set_scratch_buffer_blob(NULL);
   462   _compile->begin_method();
   463 }
   464 CompileWrapper::~CompileWrapper() {
   465   _compile->end_method();
   466   if (_compile->scratch_buffer_blob() != NULL)
   467     BufferBlob::free(_compile->scratch_buffer_blob());
   468   _compile->env()->set_compiler_data(NULL);
   469 }
   472 //----------------------------print_compile_messages---------------------------
   473 void Compile::print_compile_messages() {
   474 #ifndef PRODUCT
   475   // Check if recompiling
   476   if (_subsume_loads == false && PrintOpto) {
   477     // Recompiling without allowing machine instructions to subsume loads
   478     tty->print_cr("*********************************************************");
   479     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
   480     tty->print_cr("*********************************************************");
   481   }
   482   if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
   483     // Recompiling without escape analysis
   484     tty->print_cr("*********************************************************");
   485     tty->print_cr("** Bailout: Recompile without escape analysis          **");
   486     tty->print_cr("*********************************************************");
   487   }
   488   if (env()->break_at_compile()) {
   489     // Open the debugger when compiling this method.
   490     tty->print("### Breaking when compiling: ");
   491     method()->print_short_name();
   492     tty->cr();
   493     BREAKPOINT;
   494   }
   496   if( PrintOpto ) {
   497     if (is_osr_compilation()) {
   498       tty->print("[OSR]%3d", _compile_id);
   499     } else {
   500       tty->print("%3d", _compile_id);
   501     }
   502   }
   503 #endif
   504 }
   507 //-----------------------init_scratch_buffer_blob------------------------------
   508 // Construct a temporary BufferBlob and cache it for this compile.
   509 void Compile::init_scratch_buffer_blob(int const_size) {
   510   // If there is already a scratch buffer blob allocated and the
   511   // constant section is big enough, use it.  Otherwise free the
   512   // current and allocate a new one.
   513   BufferBlob* blob = scratch_buffer_blob();
   514   if ((blob != NULL) && (const_size <= _scratch_const_size)) {
   515     // Use the current blob.
   516   } else {
   517     if (blob != NULL) {
   518       BufferBlob::free(blob);
   519     }
   521     ResourceMark rm;
   522     _scratch_const_size = const_size;
   523     int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
   524     blob = BufferBlob::create("Compile::scratch_buffer", size);
   525     // Record the buffer blob for next time.
   526     set_scratch_buffer_blob(blob);
   527     // Have we run out of code space?
   528     if (scratch_buffer_blob() == NULL) {
   529       // Let CompilerBroker disable further compilations.
   530       record_failure("Not enough space for scratch buffer in CodeCache");
   531       return;
   532     }
   533   }
   535   // Initialize the relocation buffers
   536   relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
   537   set_scratch_locs_memory(locs_buf);
   538 }
   541 //-----------------------scratch_emit_size-------------------------------------
   542 // Helper function that computes size by emitting code
   543 uint Compile::scratch_emit_size(const Node* n) {
   544   // Start scratch_emit_size section.
   545   set_in_scratch_emit_size(true);
   547   // Emit into a trash buffer and count bytes emitted.
   548   // This is a pretty expensive way to compute a size,
   549   // but it works well enough if seldom used.
   550   // All common fixed-size instructions are given a size
   551   // method by the AD file.
   552   // Note that the scratch buffer blob and locs memory are
   553   // allocated at the beginning of the compile task, and
   554   // may be shared by several calls to scratch_emit_size.
   555   // The allocation of the scratch buffer blob is particularly
   556   // expensive, since it has to grab the code cache lock.
   557   BufferBlob* blob = this->scratch_buffer_blob();
   558   assert(blob != NULL, "Initialize BufferBlob at start");
   559   assert(blob->size() > MAX_inst_size, "sanity");
   560   relocInfo* locs_buf = scratch_locs_memory();
   561   address blob_begin = blob->content_begin();
   562   address blob_end   = (address)locs_buf;
   563   assert(blob->content_contains(blob_end), "sanity");
   564   CodeBuffer buf(blob_begin, blob_end - blob_begin);
   565   buf.initialize_consts_size(_scratch_const_size);
   566   buf.initialize_stubs_size(MAX_stubs_size);
   567   assert(locs_buf != NULL, "sanity");
   568   int lsize = MAX_locs_size / 3;
   569   buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
   570   buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
   571   buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
   573   // Do the emission.
   575   Label fakeL; // Fake label for branch instructions.
   576   Label*   saveL = NULL;
   577   uint save_bnum = 0;
   578   bool is_branch = n->is_MachBranch();
   579   if (is_branch) {
   580     MacroAssembler masm(&buf);
   581     masm.bind(fakeL);
   582     n->as_MachBranch()->save_label(&saveL, &save_bnum);
   583     n->as_MachBranch()->label_set(&fakeL, 0);
   584   }
   585   n->emit(buf, this->regalloc());
   586   if (is_branch) // Restore label.
   587     n->as_MachBranch()->label_set(saveL, save_bnum);
   589   // End scratch_emit_size section.
   590   set_in_scratch_emit_size(false);
   592   return buf.insts_size();
   593 }
   596 // ============================================================================
   597 //------------------------------Compile standard-------------------------------
   598 debug_only( int Compile::_debug_idx = 100000; )
   600 // Compile a method.  entry_bci is -1 for normal compilations and indicates
   601 // the continuation bci for on stack replacement.
   604 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci, bool subsume_loads, bool do_escape_analysis )
   605                 : Phase(Compiler),
   606                   _env(ci_env),
   607                   _log(ci_env->log()),
   608                   _compile_id(ci_env->compile_id()),
   609                   _save_argument_registers(false),
   610                   _stub_name(NULL),
   611                   _stub_function(NULL),
   612                   _stub_entry_point(NULL),
   613                   _method(target),
   614                   _entry_bci(osr_bci),
   615                   _initial_gvn(NULL),
   616                   _for_igvn(NULL),
   617                   _warm_calls(NULL),
   618                   _subsume_loads(subsume_loads),
   619                   _do_escape_analysis(do_escape_analysis),
   620                   _failure_reason(NULL),
   621                   _code_buffer("Compile::Fill_buffer"),
   622                   _orig_pc_slot(0),
   623                   _orig_pc_slot_offset_in_bytes(0),
   624                   _has_method_handle_invokes(false),
   625                   _mach_constant_base_node(NULL),
   626                   _node_bundling_limit(0),
   627                   _node_bundling_base(NULL),
   628                   _java_calls(0),
   629                   _inner_loops(0),
   630                   _scratch_const_size(-1),
   631                   _in_scratch_emit_size(false),
   632                   _dead_node_list(comp_arena()),
   633                   _dead_node_count(0),
   634 #ifndef PRODUCT
   635                   _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
   636                   _printer(IdealGraphPrinter::printer()),
   637 #endif
   638                   _congraph(NULL),
   639                   _late_inlines(comp_arena(), 2, 0, NULL),
   640                   _string_late_inlines(comp_arena(), 2, 0, NULL),
   641                   _late_inlines_pos(0),
   642                   _number_of_mh_late_inlines(0),
   643                   _inlining_progress(false),
   644                   _inlining_incrementally(false),
   645                   _print_inlining_list(NULL),
   646                   _print_inlining(0) {
   647   C = this;
   649   CompileWrapper cw(this);
   650 #ifndef PRODUCT
   651   if (TimeCompiler2) {
   652     tty->print(" ");
   653     target->holder()->name()->print();
   654     tty->print(".");
   655     target->print_short_name();
   656     tty->print("  ");
   657   }
   658   TraceTime t1("Total compilation time", &_t_totalCompilation, TimeCompiler, TimeCompiler2);
   659   TraceTime t2(NULL, &_t_methodCompilation, TimeCompiler, false);
   660   bool print_opto_assembly = PrintOptoAssembly || _method->has_option("PrintOptoAssembly");
   661   if (!print_opto_assembly) {
   662     bool print_assembly = (PrintAssembly || _method->should_print_assembly());
   663     if (print_assembly && !Disassembler::can_decode()) {
   664       tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
   665       print_opto_assembly = true;
   666     }
   667   }
   668   set_print_assembly(print_opto_assembly);
   669   set_parsed_irreducible_loop(false);
   670 #endif
   672   if (ProfileTraps) {
   673     // Make sure the method being compiled gets its own MDO,
   674     // so we can at least track the decompile_count().
   675     method()->ensure_method_data();
   676   }
   678   Init(::AliasLevel);
   681   print_compile_messages();
   683   if (UseOldInlining || PrintCompilation NOT_PRODUCT( || PrintOpto) )
   684     _ilt = InlineTree::build_inline_tree_root();
   685   else
   686     _ilt = NULL;
   688   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
   689   assert(num_alias_types() >= AliasIdxRaw, "");
   691 #define MINIMUM_NODE_HASH  1023
   692   // Node list that Iterative GVN will start with
   693   Unique_Node_List for_igvn(comp_arena());
   694   set_for_igvn(&for_igvn);
   696   // GVN that will be run immediately on new nodes
   697   uint estimated_size = method()->code_size()*4+64;
   698   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
   699   PhaseGVN gvn(node_arena(), estimated_size);
   700   set_initial_gvn(&gvn);
   702   if (PrintInlining  || PrintIntrinsics NOT_PRODUCT( || PrintOptoInlining)) {
   703     _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
   704   }
   705   { // Scope for timing the parser
   706     TracePhase t3("parse", &_t_parser, true);
   708     // Put top into the hash table ASAP.
   709     initial_gvn()->transform_no_reclaim(top());
   711     // Set up tf(), start(), and find a CallGenerator.
   712     CallGenerator* cg = NULL;
   713     if (is_osr_compilation()) {
   714       const TypeTuple *domain = StartOSRNode::osr_domain();
   715       const TypeTuple *range = TypeTuple::make_range(method()->signature());
   716       init_tf(TypeFunc::make(domain, range));
   717       StartNode* s = new (this) StartOSRNode(root(), domain);
   718       initial_gvn()->set_type_bottom(s);
   719       init_start(s);
   720       cg = CallGenerator::for_osr(method(), entry_bci());
   721     } else {
   722       // Normal case.
   723       init_tf(TypeFunc::make(method()));
   724       StartNode* s = new (this) StartNode(root(), tf()->domain());
   725       initial_gvn()->set_type_bottom(s);
   726       init_start(s);
   727       if (method()->intrinsic_id() == vmIntrinsics::_Reference_get && UseG1GC) {
   728         // With java.lang.ref.reference.get() we must go through the
   729         // intrinsic when G1 is enabled - even when get() is the root
   730         // method of the compile - so that, if necessary, the value in
   731         // the referent field of the reference object gets recorded by
   732         // the pre-barrier code.
   733         // Specifically, if G1 is enabled, the value in the referent
   734         // field is recorded by the G1 SATB pre barrier. This will
   735         // result in the referent being marked live and the reference
   736         // object removed from the list of discovered references during
   737         // reference processing.
   738         cg = find_intrinsic(method(), false);
   739       }
   740       if (cg == NULL) {
   741         float past_uses = method()->interpreter_invocation_count();
   742         float expected_uses = past_uses;
   743         cg = CallGenerator::for_inline(method(), expected_uses);
   744       }
   745     }
   746     if (failing())  return;
   747     if (cg == NULL) {
   748       record_method_not_compilable_all_tiers("cannot parse method");
   749       return;
   750     }
   751     JVMState* jvms = build_start_state(start(), tf());
   752     if ((jvms = cg->generate(jvms)) == NULL) {
   753       record_method_not_compilable("method parse failed");
   754       return;
   755     }
   756     GraphKit kit(jvms);
   758     if (!kit.stopped()) {
   759       // Accept return values, and transfer control we know not where.
   760       // This is done by a special, unique ReturnNode bound to root.
   761       return_values(kit.jvms());
   762     }
   764     if (kit.has_exceptions()) {
   765       // Any exceptions that escape from this call must be rethrown
   766       // to whatever caller is dynamically above us on the stack.
   767       // This is done by a special, unique RethrowNode bound to root.
   768       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
   769     }
   771     assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
   773     if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
   774       inline_string_calls(true);
   775     }
   777     if (failing())  return;
   779     print_method("Before RemoveUseless", 3);
   781     // Remove clutter produced by parsing.
   782     if (!failing()) {
   783       ResourceMark rm;
   784       PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
   785     }
   786   }
   788   // Note:  Large methods are capped off in do_one_bytecode().
   789   if (failing())  return;
   791   // After parsing, node notes are no longer automagic.
   792   // They must be propagated by register_new_node_with_optimizer(),
   793   // clone(), or the like.
   794   set_default_node_notes(NULL);
   796   for (;;) {
   797     int successes = Inline_Warm();
   798     if (failing())  return;
   799     if (successes == 0)  break;
   800   }
   802   // Drain the list.
   803   Finish_Warm();
   804 #ifndef PRODUCT
   805   if (_printer) {
   806     _printer->print_inlining(this);
   807   }
   808 #endif
   810   if (failing())  return;
   811   NOT_PRODUCT( verify_graph_edges(); )
   813   // Now optimize
   814   Optimize();
   815   if (failing())  return;
   816   NOT_PRODUCT( verify_graph_edges(); )
   818 #ifndef PRODUCT
   819   if (PrintIdeal) {
   820     ttyLocker ttyl;  // keep the following output all in one block
   821     // This output goes directly to the tty, not the compiler log.
   822     // To enable tools to match it up with the compilation activity,
   823     // be sure to tag this tty output with the compile ID.
   824     if (xtty != NULL) {
   825       xtty->head("ideal compile_id='%d'%s", compile_id(),
   826                  is_osr_compilation()    ? " compile_kind='osr'" :
   827                  "");
   828     }
   829     root()->dump(9999);
   830     if (xtty != NULL) {
   831       xtty->tail("ideal");
   832     }
   833   }
   834 #endif
   836   // Now that we know the size of all the monitors we can add a fixed slot
   837   // for the original deopt pc.
   839   _orig_pc_slot =  fixed_slots();
   840   int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
   841   set_fixed_slots(next_slot);
   843   // Now generate code
   844   Code_Gen();
   845   if (failing())  return;
   847   // Check if we want to skip execution of all compiled code.
   848   {
   849 #ifndef PRODUCT
   850     if (OptoNoExecute) {
   851       record_method_not_compilable("+OptoNoExecute");  // Flag as failed
   852       return;
   853     }
   854     TracePhase t2("install_code", &_t_registerMethod, TimeCompiler);
   855 #endif
   857     if (is_osr_compilation()) {
   858       _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
   859       _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
   860     } else {
   861       _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
   862       _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
   863     }
   865     env()->register_method(_method, _entry_bci,
   866                            &_code_offsets,
   867                            _orig_pc_slot_offset_in_bytes,
   868                            code_buffer(),
   869                            frame_size_in_words(), _oop_map_set,
   870                            &_handler_table, &_inc_table,
   871                            compiler,
   872                            env()->comp_level(),
   873                            has_unsafe_access(),
   874                            SharedRuntime::is_wide_vector(max_vector_size())
   875                            );
   877     if (log() != NULL) // Print code cache state into compiler log
   878       log()->code_cache_state();
   879   }
   880 }
   882 //------------------------------Compile----------------------------------------
   883 // Compile a runtime stub
   884 Compile::Compile( ciEnv* ci_env,
   885                   TypeFunc_generator generator,
   886                   address stub_function,
   887                   const char *stub_name,
   888                   int is_fancy_jump,
   889                   bool pass_tls,
   890                   bool save_arg_registers,
   891                   bool return_pc )
   892   : Phase(Compiler),
   893     _env(ci_env),
   894     _log(ci_env->log()),
   895     _compile_id(0),
   896     _save_argument_registers(save_arg_registers),
   897     _method(NULL),
   898     _stub_name(stub_name),
   899     _stub_function(stub_function),
   900     _stub_entry_point(NULL),
   901     _entry_bci(InvocationEntryBci),
   902     _initial_gvn(NULL),
   903     _for_igvn(NULL),
   904     _warm_calls(NULL),
   905     _orig_pc_slot(0),
   906     _orig_pc_slot_offset_in_bytes(0),
   907     _subsume_loads(true),
   908     _do_escape_analysis(false),
   909     _failure_reason(NULL),
   910     _code_buffer("Compile::Fill_buffer"),
   911     _has_method_handle_invokes(false),
   912     _mach_constant_base_node(NULL),
   913     _node_bundling_limit(0),
   914     _node_bundling_base(NULL),
   915     _java_calls(0),
   916     _inner_loops(0),
   917 #ifndef PRODUCT
   918     _trace_opto_output(TraceOptoOutput),
   919     _printer(NULL),
   920 #endif
   921     _dead_node_list(comp_arena()),
   922     _dead_node_count(0),
   923     _congraph(NULL),
   924     _number_of_mh_late_inlines(0),
   925     _inlining_progress(false),
   926     _inlining_incrementally(false),
   927     _print_inlining_list(NULL),
   928     _print_inlining(0) {
   929   C = this;
   931 #ifndef PRODUCT
   932   TraceTime t1(NULL, &_t_totalCompilation, TimeCompiler, false);
   933   TraceTime t2(NULL, &_t_stubCompilation, TimeCompiler, false);
   934   set_print_assembly(PrintFrameConverterAssembly);
   935   set_parsed_irreducible_loop(false);
   936 #endif
   937   CompileWrapper cw(this);
   938   Init(/*AliasLevel=*/ 0);
   939   init_tf((*generator)());
   941   {
   942     // The following is a dummy for the sake of GraphKit::gen_stub
   943     Unique_Node_List for_igvn(comp_arena());
   944     set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
   945     PhaseGVN gvn(Thread::current()->resource_area(),255);
   946     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
   947     gvn.transform_no_reclaim(top());
   949     GraphKit kit;
   950     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
   951   }
   953   NOT_PRODUCT( verify_graph_edges(); )
   954   Code_Gen();
   955   if (failing())  return;
   958   // Entry point will be accessed using compile->stub_entry_point();
   959   if (code_buffer() == NULL) {
   960     Matcher::soft_match_failure();
   961   } else {
   962     if (PrintAssembly && (WizardMode || Verbose))
   963       tty->print_cr("### Stub::%s", stub_name);
   965     if (!failing()) {
   966       assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
   968       // Make the NMethod
   969       // For now we mark the frame as never safe for profile stackwalking
   970       RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
   971                                                       code_buffer(),
   972                                                       CodeOffsets::frame_never_safe,
   973                                                       // _code_offsets.value(CodeOffsets::Frame_Complete),
   974                                                       frame_size_in_words(),
   975                                                       _oop_map_set,
   976                                                       save_arg_registers);
   977       assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
   979       _stub_entry_point = rs->entry_point();
   980     }
   981   }
   982 }
   984 //------------------------------Init-------------------------------------------
   985 // Prepare for a single compilation
   986 void Compile::Init(int aliaslevel) {
   987   _unique  = 0;
   988   _regalloc = NULL;
   990   _tf      = NULL;  // filled in later
   991   _top     = NULL;  // cached later
   992   _matcher = NULL;  // filled in later
   993   _cfg     = NULL;  // filled in later
   995   set_24_bit_selection_and_mode(Use24BitFP, false);
   997   _node_note_array = NULL;
   998   _default_node_notes = NULL;
  1000   _immutable_memory = NULL; // filled in at first inquiry
  1002   // Globally visible Nodes
  1003   // First set TOP to NULL to give safe behavior during creation of RootNode
  1004   set_cached_top_node(NULL);
  1005   set_root(new (this) RootNode());
  1006   // Now that you have a Root to point to, create the real TOP
  1007   set_cached_top_node( new (this) ConNode(Type::TOP) );
  1008   set_recent_alloc(NULL, NULL);
  1010   // Create Debug Information Recorder to record scopes, oopmaps, etc.
  1011   env()->set_oop_recorder(new OopRecorder(env()->arena()));
  1012   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
  1013   env()->set_dependencies(new Dependencies(env()));
  1015   _fixed_slots = 0;
  1016   set_has_split_ifs(false);
  1017   set_has_loops(has_method() && method()->has_loops()); // first approximation
  1018   set_has_stringbuilder(false);
  1019   _trap_can_recompile = false;  // no traps emitted yet
  1020   _major_progress = true; // start out assuming good things will happen
  1021   set_has_unsafe_access(false);
  1022   set_max_vector_size(0);
  1023   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
  1024   set_decompile_count(0);
  1026   set_do_freq_based_layout(BlockLayoutByFrequency || method_has_option("BlockLayoutByFrequency"));
  1027   set_num_loop_opts(LoopOptsCount);
  1028   set_do_inlining(Inline);
  1029   set_max_inline_size(MaxInlineSize);
  1030   set_freq_inline_size(FreqInlineSize);
  1031   set_do_scheduling(OptoScheduling);
  1032   set_do_count_invocations(false);
  1033   set_do_method_data_update(false);
  1035   if (debug_info()->recording_non_safepoints()) {
  1036     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
  1037                         (comp_arena(), 8, 0, NULL));
  1038     set_default_node_notes(Node_Notes::make(this));
  1041   // // -- Initialize types before each compile --
  1042   // // Update cached type information
  1043   // if( _method && _method->constants() )
  1044   //   Type::update_loaded_types(_method, _method->constants());
  1046   // Init alias_type map.
  1047   if (!_do_escape_analysis && aliaslevel == 3)
  1048     aliaslevel = 2;  // No unique types without escape analysis
  1049   _AliasLevel = aliaslevel;
  1050   const int grow_ats = 16;
  1051   _max_alias_types = grow_ats;
  1052   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
  1053   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
  1054   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
  1056     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
  1058   // Initialize the first few types.
  1059   _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
  1060   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
  1061   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
  1062   _num_alias_types = AliasIdxRaw+1;
  1063   // Zero out the alias type cache.
  1064   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
  1065   // A NULL adr_type hits in the cache right away.  Preload the right answer.
  1066   probe_alias_cache(NULL)->_index = AliasIdxTop;
  1068   _intrinsics = NULL;
  1069   _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1070   _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1071   _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1072   register_library_intrinsics();
  1075 //---------------------------init_start----------------------------------------
  1076 // Install the StartNode on this compile object.
  1077 void Compile::init_start(StartNode* s) {
  1078   if (failing())
  1079     return; // already failing
  1080   assert(s == start(), "");
  1083 StartNode* Compile::start() const {
  1084   assert(!failing(), "");
  1085   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
  1086     Node* start = root()->fast_out(i);
  1087     if( start->is_Start() )
  1088       return start->as_Start();
  1090   ShouldNotReachHere();
  1091   return NULL;
  1094 //-------------------------------immutable_memory-------------------------------------
  1095 // Access immutable memory
  1096 Node* Compile::immutable_memory() {
  1097   if (_immutable_memory != NULL) {
  1098     return _immutable_memory;
  1100   StartNode* s = start();
  1101   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
  1102     Node *p = s->fast_out(i);
  1103     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
  1104       _immutable_memory = p;
  1105       return _immutable_memory;
  1108   ShouldNotReachHere();
  1109   return NULL;
  1112 //----------------------set_cached_top_node------------------------------------
  1113 // Install the cached top node, and make sure Node::is_top works correctly.
  1114 void Compile::set_cached_top_node(Node* tn) {
  1115   if (tn != NULL)  verify_top(tn);
  1116   Node* old_top = _top;
  1117   _top = tn;
  1118   // Calling Node::setup_is_top allows the nodes the chance to adjust
  1119   // their _out arrays.
  1120   if (_top != NULL)     _top->setup_is_top();
  1121   if (old_top != NULL)  old_top->setup_is_top();
  1122   assert(_top == NULL || top()->is_top(), "");
  1125 #ifdef ASSERT
  1126 uint Compile::count_live_nodes_by_graph_walk() {
  1127   Unique_Node_List useful(comp_arena());
  1128   // Get useful node list by walking the graph.
  1129   identify_useful_nodes(useful);
  1130   return useful.size();
  1133 void Compile::print_missing_nodes() {
  1135   // Return if CompileLog is NULL and PrintIdealNodeCount is false.
  1136   if ((_log == NULL) && (! PrintIdealNodeCount)) {
  1137     return;
  1140   // This is an expensive function. It is executed only when the user
  1141   // specifies VerifyIdealNodeCount option or otherwise knows the
  1142   // additional work that needs to be done to identify reachable nodes
  1143   // by walking the flow graph and find the missing ones using
  1144   // _dead_node_list.
  1146   Unique_Node_List useful(comp_arena());
  1147   // Get useful node list by walking the graph.
  1148   identify_useful_nodes(useful);
  1150   uint l_nodes = C->live_nodes();
  1151   uint l_nodes_by_walk = useful.size();
  1153   if (l_nodes != l_nodes_by_walk) {
  1154     if (_log != NULL) {
  1155       _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
  1156       _log->stamp();
  1157       _log->end_head();
  1159     VectorSet& useful_member_set = useful.member_set();
  1160     int last_idx = l_nodes_by_walk;
  1161     for (int i = 0; i < last_idx; i++) {
  1162       if (useful_member_set.test(i)) {
  1163         if (_dead_node_list.test(i)) {
  1164           if (_log != NULL) {
  1165             _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
  1167           if (PrintIdealNodeCount) {
  1168             // Print the log message to tty
  1169               tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
  1170               useful.at(i)->dump();
  1174       else if (! _dead_node_list.test(i)) {
  1175         if (_log != NULL) {
  1176           _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
  1178         if (PrintIdealNodeCount) {
  1179           // Print the log message to tty
  1180           tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
  1184     if (_log != NULL) {
  1185       _log->tail("mismatched_nodes");
  1189 #endif
  1191 #ifndef PRODUCT
  1192 void Compile::verify_top(Node* tn) const {
  1193   if (tn != NULL) {
  1194     assert(tn->is_Con(), "top node must be a constant");
  1195     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
  1196     assert(tn->in(0) != NULL, "must have live top node");
  1199 #endif
  1202 ///-------------------Managing Per-Node Debug & Profile Info-------------------
  1204 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
  1205   guarantee(arr != NULL, "");
  1206   int num_blocks = arr->length();
  1207   if (grow_by < num_blocks)  grow_by = num_blocks;
  1208   int num_notes = grow_by * _node_notes_block_size;
  1209   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
  1210   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
  1211   while (num_notes > 0) {
  1212     arr->append(notes);
  1213     notes     += _node_notes_block_size;
  1214     num_notes -= _node_notes_block_size;
  1216   assert(num_notes == 0, "exact multiple, please");
  1219 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
  1220   if (source == NULL || dest == NULL)  return false;
  1222   if (dest->is_Con())
  1223     return false;               // Do not push debug info onto constants.
  1225 #ifdef ASSERT
  1226   // Leave a bread crumb trail pointing to the original node:
  1227   if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
  1228     dest->set_debug_orig(source);
  1230 #endif
  1232   if (node_note_array() == NULL)
  1233     return false;               // Not collecting any notes now.
  1235   // This is a copy onto a pre-existing node, which may already have notes.
  1236   // If both nodes have notes, do not overwrite any pre-existing notes.
  1237   Node_Notes* source_notes = node_notes_at(source->_idx);
  1238   if (source_notes == NULL || source_notes->is_clear())  return false;
  1239   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
  1240   if (dest_notes == NULL || dest_notes->is_clear()) {
  1241     return set_node_notes_at(dest->_idx, source_notes);
  1244   Node_Notes merged_notes = (*source_notes);
  1245   // The order of operations here ensures that dest notes will win...
  1246   merged_notes.update_from(dest_notes);
  1247   return set_node_notes_at(dest->_idx, &merged_notes);
  1251 //--------------------------allow_range_check_smearing-------------------------
  1252 // Gating condition for coalescing similar range checks.
  1253 // Sometimes we try 'speculatively' replacing a series of a range checks by a
  1254 // single covering check that is at least as strong as any of them.
  1255 // If the optimization succeeds, the simplified (strengthened) range check
  1256 // will always succeed.  If it fails, we will deopt, and then give up
  1257 // on the optimization.
  1258 bool Compile::allow_range_check_smearing() const {
  1259   // If this method has already thrown a range-check,
  1260   // assume it was because we already tried range smearing
  1261   // and it failed.
  1262   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
  1263   return !already_trapped;
  1267 //------------------------------flatten_alias_type-----------------------------
  1268 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
  1269   int offset = tj->offset();
  1270   TypePtr::PTR ptr = tj->ptr();
  1272   // Known instance (scalarizable allocation) alias only with itself.
  1273   bool is_known_inst = tj->isa_oopptr() != NULL &&
  1274                        tj->is_oopptr()->is_known_instance();
  1276   // Process weird unsafe references.
  1277   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
  1278     assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
  1279     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
  1280     tj = TypeOopPtr::BOTTOM;
  1281     ptr = tj->ptr();
  1282     offset = tj->offset();
  1285   // Array pointers need some flattening
  1286   const TypeAryPtr *ta = tj->isa_aryptr();
  1287   if( ta && is_known_inst ) {
  1288     if ( offset != Type::OffsetBot &&
  1289          offset > arrayOopDesc::length_offset_in_bytes() ) {
  1290       offset = Type::OffsetBot; // Flatten constant access into array body only
  1291       tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
  1293   } else if( ta && _AliasLevel >= 2 ) {
  1294     // For arrays indexed by constant indices, we flatten the alias
  1295     // space to include all of the array body.  Only the header, klass
  1296     // and array length can be accessed un-aliased.
  1297     if( offset != Type::OffsetBot ) {
  1298       if( ta->const_oop() ) { // MethodData* or Method*
  1299         offset = Type::OffsetBot;   // Flatten constant access into array body
  1300         tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
  1301       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
  1302         // range is OK as-is.
  1303         tj = ta = TypeAryPtr::RANGE;
  1304       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
  1305         tj = TypeInstPtr::KLASS; // all klass loads look alike
  1306         ta = TypeAryPtr::RANGE; // generic ignored junk
  1307         ptr = TypePtr::BotPTR;
  1308       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
  1309         tj = TypeInstPtr::MARK;
  1310         ta = TypeAryPtr::RANGE; // generic ignored junk
  1311         ptr = TypePtr::BotPTR;
  1312       } else {                  // Random constant offset into array body
  1313         offset = Type::OffsetBot;   // Flatten constant access into array body
  1314         tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
  1317     // Arrays of fixed size alias with arrays of unknown size.
  1318     if (ta->size() != TypeInt::POS) {
  1319       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
  1320       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
  1322     // Arrays of known objects become arrays of unknown objects.
  1323     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
  1324       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
  1325       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
  1327     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
  1328       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
  1329       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
  1331     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
  1332     // cannot be distinguished by bytecode alone.
  1333     if (ta->elem() == TypeInt::BOOL) {
  1334       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
  1335       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
  1336       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
  1338     // During the 2nd round of IterGVN, NotNull castings are removed.
  1339     // Make sure the Bottom and NotNull variants alias the same.
  1340     // Also, make sure exact and non-exact variants alias the same.
  1341     if( ptr == TypePtr::NotNull || ta->klass_is_exact() ) {
  1342       tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
  1346   // Oop pointers need some flattening
  1347   const TypeInstPtr *to = tj->isa_instptr();
  1348   if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
  1349     ciInstanceKlass *k = to->klass()->as_instance_klass();
  1350     if( ptr == TypePtr::Constant ) {
  1351       if (to->klass() != ciEnv::current()->Class_klass() ||
  1352           offset < k->size_helper() * wordSize) {
  1353         // No constant oop pointers (such as Strings); they alias with
  1354         // unknown strings.
  1355         assert(!is_known_inst, "not scalarizable allocation");
  1356         tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
  1358     } else if( is_known_inst ) {
  1359       tj = to; // Keep NotNull and klass_is_exact for instance type
  1360     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
  1361       // During the 2nd round of IterGVN, NotNull castings are removed.
  1362       // Make sure the Bottom and NotNull variants alias the same.
  1363       // Also, make sure exact and non-exact variants alias the same.
  1364       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
  1366     // Canonicalize the holder of this field
  1367     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
  1368       // First handle header references such as a LoadKlassNode, even if the
  1369       // object's klass is unloaded at compile time (4965979).
  1370       if (!is_known_inst) { // Do it only for non-instance types
  1371         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
  1373     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
  1374       // Static fields are in the space above the normal instance
  1375       // fields in the java.lang.Class instance.
  1376       if (to->klass() != ciEnv::current()->Class_klass()) {
  1377         to = NULL;
  1378         tj = TypeOopPtr::BOTTOM;
  1379         offset = tj->offset();
  1381     } else {
  1382       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
  1383       if (!k->equals(canonical_holder) || tj->offset() != offset) {
  1384         if( is_known_inst ) {
  1385           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
  1386         } else {
  1387           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
  1393   // Klass pointers to object array klasses need some flattening
  1394   const TypeKlassPtr *tk = tj->isa_klassptr();
  1395   if( tk ) {
  1396     // If we are referencing a field within a Klass, we need
  1397     // to assume the worst case of an Object.  Both exact and
  1398     // inexact types must flatten to the same alias class so
  1399     // use NotNull as the PTR.
  1400     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
  1402       tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
  1403                                    TypeKlassPtr::OBJECT->klass(),
  1404                                    offset);
  1407     ciKlass* klass = tk->klass();
  1408     if( klass->is_obj_array_klass() ) {
  1409       ciKlass* k = TypeAryPtr::OOPS->klass();
  1410       if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
  1411         k = TypeInstPtr::BOTTOM->klass();
  1412       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
  1415     // Check for precise loads from the primary supertype array and force them
  1416     // to the supertype cache alias index.  Check for generic array loads from
  1417     // the primary supertype array and also force them to the supertype cache
  1418     // alias index.  Since the same load can reach both, we need to merge
  1419     // these 2 disparate memories into the same alias class.  Since the
  1420     // primary supertype array is read-only, there's no chance of confusion
  1421     // where we bypass an array load and an array store.
  1422     int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
  1423     if (offset == Type::OffsetBot ||
  1424         (offset >= primary_supers_offset &&
  1425          offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
  1426         offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
  1427       offset = in_bytes(Klass::secondary_super_cache_offset());
  1428       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
  1432   // Flatten all Raw pointers together.
  1433   if (tj->base() == Type::RawPtr)
  1434     tj = TypeRawPtr::BOTTOM;
  1436   if (tj->base() == Type::AnyPtr)
  1437     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
  1439   // Flatten all to bottom for now
  1440   switch( _AliasLevel ) {
  1441   case 0:
  1442     tj = TypePtr::BOTTOM;
  1443     break;
  1444   case 1:                       // Flatten to: oop, static, field or array
  1445     switch (tj->base()) {
  1446     //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
  1447     case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
  1448     case Type::AryPtr:   // do not distinguish arrays at all
  1449     case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
  1450     case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
  1451     case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
  1452     default: ShouldNotReachHere();
  1454     break;
  1455   case 2:                       // No collapsing at level 2; keep all splits
  1456   case 3:                       // No collapsing at level 3; keep all splits
  1457     break;
  1458   default:
  1459     Unimplemented();
  1462   offset = tj->offset();
  1463   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
  1465   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
  1466           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
  1467           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
  1468           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
  1469           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
  1470           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
  1471           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr)  ,
  1472           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
  1473   assert( tj->ptr() != TypePtr::TopPTR &&
  1474           tj->ptr() != TypePtr::AnyNull &&
  1475           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
  1476 //    assert( tj->ptr() != TypePtr::Constant ||
  1477 //            tj->base() == Type::RawPtr ||
  1478 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
  1480   return tj;
  1483 void Compile::AliasType::Init(int i, const TypePtr* at) {
  1484   _index = i;
  1485   _adr_type = at;
  1486   _field = NULL;
  1487   _is_rewritable = true; // default
  1488   const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
  1489   if (atoop != NULL && atoop->is_known_instance()) {
  1490     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
  1491     _general_index = Compile::current()->get_alias_index(gt);
  1492   } else {
  1493     _general_index = 0;
  1497 //---------------------------------print_on------------------------------------
  1498 #ifndef PRODUCT
  1499 void Compile::AliasType::print_on(outputStream* st) {
  1500   if (index() < 10)
  1501         st->print("@ <%d> ", index());
  1502   else  st->print("@ <%d>",  index());
  1503   st->print(is_rewritable() ? "   " : " RO");
  1504   int offset = adr_type()->offset();
  1505   if (offset == Type::OffsetBot)
  1506         st->print(" +any");
  1507   else  st->print(" +%-3d", offset);
  1508   st->print(" in ");
  1509   adr_type()->dump_on(st);
  1510   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
  1511   if (field() != NULL && tjp) {
  1512     if (tjp->klass()  != field()->holder() ||
  1513         tjp->offset() != field()->offset_in_bytes()) {
  1514       st->print(" != ");
  1515       field()->print();
  1516       st->print(" ***");
  1521 void print_alias_types() {
  1522   Compile* C = Compile::current();
  1523   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
  1524   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
  1525     C->alias_type(idx)->print_on(tty);
  1526     tty->cr();
  1529 #endif
  1532 //----------------------------probe_alias_cache--------------------------------
  1533 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
  1534   intptr_t key = (intptr_t) adr_type;
  1535   key ^= key >> logAliasCacheSize;
  1536   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
  1540 //-----------------------------grow_alias_types--------------------------------
  1541 void Compile::grow_alias_types() {
  1542   const int old_ats  = _max_alias_types; // how many before?
  1543   const int new_ats  = old_ats;          // how many more?
  1544   const int grow_ats = old_ats+new_ats;  // how many now?
  1545   _max_alias_types = grow_ats;
  1546   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
  1547   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
  1548   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
  1549   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
  1553 //--------------------------------find_alias_type------------------------------
  1554 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
  1555   if (_AliasLevel == 0)
  1556     return alias_type(AliasIdxBot);
  1558   AliasCacheEntry* ace = probe_alias_cache(adr_type);
  1559   if (ace->_adr_type == adr_type) {
  1560     return alias_type(ace->_index);
  1563   // Handle special cases.
  1564   if (adr_type == NULL)             return alias_type(AliasIdxTop);
  1565   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
  1567   // Do it the slow way.
  1568   const TypePtr* flat = flatten_alias_type(adr_type);
  1570 #ifdef ASSERT
  1571   assert(flat == flatten_alias_type(flat), "idempotent");
  1572   assert(flat != TypePtr::BOTTOM,     "cannot alias-analyze an untyped ptr");
  1573   if (flat->isa_oopptr() && !flat->isa_klassptr()) {
  1574     const TypeOopPtr* foop = flat->is_oopptr();
  1575     // Scalarizable allocations have exact klass always.
  1576     bool exact = !foop->klass_is_exact() || foop->is_known_instance();
  1577     const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
  1578     assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type");
  1580   assert(flat == flatten_alias_type(flat), "exact bit doesn't matter");
  1581 #endif
  1583   int idx = AliasIdxTop;
  1584   for (int i = 0; i < num_alias_types(); i++) {
  1585     if (alias_type(i)->adr_type() == flat) {
  1586       idx = i;
  1587       break;
  1591   if (idx == AliasIdxTop) {
  1592     if (no_create)  return NULL;
  1593     // Grow the array if necessary.
  1594     if (_num_alias_types == _max_alias_types)  grow_alias_types();
  1595     // Add a new alias type.
  1596     idx = _num_alias_types++;
  1597     _alias_types[idx]->Init(idx, flat);
  1598     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
  1599     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
  1600     if (flat->isa_instptr()) {
  1601       if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
  1602           && flat->is_instptr()->klass() == env()->Class_klass())
  1603         alias_type(idx)->set_rewritable(false);
  1605     if (flat->isa_klassptr()) {
  1606       if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
  1607         alias_type(idx)->set_rewritable(false);
  1608       if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
  1609         alias_type(idx)->set_rewritable(false);
  1610       if (flat->offset() == in_bytes(Klass::access_flags_offset()))
  1611         alias_type(idx)->set_rewritable(false);
  1612       if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
  1613         alias_type(idx)->set_rewritable(false);
  1615     // %%% (We would like to finalize JavaThread::threadObj_offset(),
  1616     // but the base pointer type is not distinctive enough to identify
  1617     // references into JavaThread.)
  1619     // Check for final fields.
  1620     const TypeInstPtr* tinst = flat->isa_instptr();
  1621     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
  1622       ciField* field;
  1623       if (tinst->const_oop() != NULL &&
  1624           tinst->klass() == ciEnv::current()->Class_klass() &&
  1625           tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
  1626         // static field
  1627         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
  1628         field = k->get_field_by_offset(tinst->offset(), true);
  1629       } else {
  1630         ciInstanceKlass *k = tinst->klass()->as_instance_klass();
  1631         field = k->get_field_by_offset(tinst->offset(), false);
  1633       assert(field == NULL ||
  1634              original_field == NULL ||
  1635              (field->holder() == original_field->holder() &&
  1636               field->offset() == original_field->offset() &&
  1637               field->is_static() == original_field->is_static()), "wrong field?");
  1638       // Set field() and is_rewritable() attributes.
  1639       if (field != NULL)  alias_type(idx)->set_field(field);
  1643   // Fill the cache for next time.
  1644   ace->_adr_type = adr_type;
  1645   ace->_index    = idx;
  1646   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
  1648   // Might as well try to fill the cache for the flattened version, too.
  1649   AliasCacheEntry* face = probe_alias_cache(flat);
  1650   if (face->_adr_type == NULL) {
  1651     face->_adr_type = flat;
  1652     face->_index    = idx;
  1653     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
  1656   return alias_type(idx);
  1660 Compile::AliasType* Compile::alias_type(ciField* field) {
  1661   const TypeOopPtr* t;
  1662   if (field->is_static())
  1663     t = TypeInstPtr::make(field->holder()->java_mirror());
  1664   else
  1665     t = TypeOopPtr::make_from_klass_raw(field->holder());
  1666   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
  1667   assert(field->is_final() == !atp->is_rewritable(), "must get the rewritable bits correct");
  1668   return atp;
  1672 //------------------------------have_alias_type--------------------------------
  1673 bool Compile::have_alias_type(const TypePtr* adr_type) {
  1674   AliasCacheEntry* ace = probe_alias_cache(adr_type);
  1675   if (ace->_adr_type == adr_type) {
  1676     return true;
  1679   // Handle special cases.
  1680   if (adr_type == NULL)             return true;
  1681   if (adr_type == TypePtr::BOTTOM)  return true;
  1683   return find_alias_type(adr_type, true, NULL) != NULL;
  1686 //-----------------------------must_alias--------------------------------------
  1687 // True if all values of the given address type are in the given alias category.
  1688 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
  1689   if (alias_idx == AliasIdxBot)         return true;  // the universal category
  1690   if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
  1691   if (alias_idx == AliasIdxTop)         return false; // the empty category
  1692   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
  1694   // the only remaining possible overlap is identity
  1695   int adr_idx = get_alias_index(adr_type);
  1696   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
  1697   assert(adr_idx == alias_idx ||
  1698          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
  1699           && adr_type                       != TypeOopPtr::BOTTOM),
  1700          "should not be testing for overlap with an unsafe pointer");
  1701   return adr_idx == alias_idx;
  1704 //------------------------------can_alias--------------------------------------
  1705 // True if any values of the given address type are in the given alias category.
  1706 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
  1707   if (alias_idx == AliasIdxTop)         return false; // the empty category
  1708   if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
  1709   if (alias_idx == AliasIdxBot)         return true;  // the universal category
  1710   if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
  1712   // the only remaining possible overlap is identity
  1713   int adr_idx = get_alias_index(adr_type);
  1714   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
  1715   return adr_idx == alias_idx;
  1720 //---------------------------pop_warm_call-------------------------------------
  1721 WarmCallInfo* Compile::pop_warm_call() {
  1722   WarmCallInfo* wci = _warm_calls;
  1723   if (wci != NULL)  _warm_calls = wci->remove_from(wci);
  1724   return wci;
  1727 //----------------------------Inline_Warm--------------------------------------
  1728 int Compile::Inline_Warm() {
  1729   // If there is room, try to inline some more warm call sites.
  1730   // %%% Do a graph index compaction pass when we think we're out of space?
  1731   if (!InlineWarmCalls)  return 0;
  1733   int calls_made_hot = 0;
  1734   int room_to_grow   = NodeCountInliningCutoff - unique();
  1735   int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
  1736   int amount_grown   = 0;
  1737   WarmCallInfo* call;
  1738   while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
  1739     int est_size = (int)call->size();
  1740     if (est_size > (room_to_grow - amount_grown)) {
  1741       // This one won't fit anyway.  Get rid of it.
  1742       call->make_cold();
  1743       continue;
  1745     call->make_hot();
  1746     calls_made_hot++;
  1747     amount_grown   += est_size;
  1748     amount_to_grow -= est_size;
  1751   if (calls_made_hot > 0)  set_major_progress();
  1752   return calls_made_hot;
  1756 //----------------------------Finish_Warm--------------------------------------
  1757 void Compile::Finish_Warm() {
  1758   if (!InlineWarmCalls)  return;
  1759   if (failing())  return;
  1760   if (warm_calls() == NULL)  return;
  1762   // Clean up loose ends, if we are out of space for inlining.
  1763   WarmCallInfo* call;
  1764   while ((call = pop_warm_call()) != NULL) {
  1765     call->make_cold();
  1769 //---------------------cleanup_loop_predicates-----------------------
  1770 // Remove the opaque nodes that protect the predicates so that all unused
  1771 // checks and uncommon_traps will be eliminated from the ideal graph
  1772 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
  1773   if (predicate_count()==0) return;
  1774   for (int i = predicate_count(); i > 0; i--) {
  1775     Node * n = predicate_opaque1_node(i-1);
  1776     assert(n->Opcode() == Op_Opaque1, "must be");
  1777     igvn.replace_node(n, n->in(1));
  1779   assert(predicate_count()==0, "should be clean!");
  1782 // StringOpts and late inlining of string methods
  1783 void Compile::inline_string_calls(bool parse_time) {
  1785     // remove useless nodes to make the usage analysis simpler
  1786     ResourceMark rm;
  1787     PhaseRemoveUseless pru(initial_gvn(), for_igvn());
  1791     ResourceMark rm;
  1792     print_method("Before StringOpts", 3);
  1793     PhaseStringOpts pso(initial_gvn(), for_igvn());
  1794     print_method("After StringOpts", 3);
  1797   // now inline anything that we skipped the first time around
  1798   if (!parse_time) {
  1799     _late_inlines_pos = _late_inlines.length();
  1802   while (_string_late_inlines.length() > 0) {
  1803     CallGenerator* cg = _string_late_inlines.pop();
  1804     cg->do_late_inline();
  1805     if (failing())  return;
  1807   _string_late_inlines.trunc_to(0);
  1810 void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
  1811   assert(IncrementalInline, "incremental inlining should be on");
  1812   PhaseGVN* gvn = initial_gvn();
  1814   set_inlining_progress(false);
  1815   for_igvn()->clear();
  1816   gvn->replace_with(&igvn);
  1818   int i = 0;
  1820   for (; i <_late_inlines.length() && !inlining_progress(); i++) {
  1821     CallGenerator* cg = _late_inlines.at(i);
  1822     _late_inlines_pos = i+1;
  1823     cg->do_late_inline();
  1824     if (failing())  return;
  1826   int j = 0;
  1827   for (; i < _late_inlines.length(); i++, j++) {
  1828     _late_inlines.at_put(j, _late_inlines.at(i));
  1830   _late_inlines.trunc_to(j);
  1833     ResourceMark rm;
  1834     PhaseRemoveUseless pru(C->initial_gvn(), C->for_igvn());
  1837   igvn = PhaseIterGVN(gvn);
  1840 // Perform incremental inlining until bound on number of live nodes is reached
  1841 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
  1842   PhaseGVN* gvn = initial_gvn();
  1844   set_inlining_incrementally(true);
  1845   set_inlining_progress(true);
  1846   uint low_live_nodes = 0;
  1848   while(inlining_progress() && _late_inlines.length() > 0) {
  1850     if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
  1851       if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
  1852         // PhaseIdealLoop is expensive so we only try it once we are
  1853         // out of loop and we only try it again if the previous helped
  1854         // got the number of nodes down significantly
  1855         PhaseIdealLoop ideal_loop( igvn, false, true );
  1856         if (failing())  return;
  1857         low_live_nodes = live_nodes();
  1858         _major_progress = true;
  1861       if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
  1862         break;
  1866     inline_incrementally_one(igvn);
  1868     if (failing())  return;
  1870     igvn.optimize();
  1872     if (failing())  return;
  1875   assert( igvn._worklist.size() == 0, "should be done with igvn" );
  1877   if (_string_late_inlines.length() > 0) {
  1878     assert(has_stringbuilder(), "inconsistent");
  1879     for_igvn()->clear();
  1880     initial_gvn()->replace_with(&igvn);
  1882     inline_string_calls(false);
  1884     if (failing())  return;
  1887       ResourceMark rm;
  1888       PhaseRemoveUseless pru(initial_gvn(), for_igvn());
  1891     igvn = PhaseIterGVN(gvn);
  1893     igvn.optimize();
  1896   set_inlining_incrementally(false);
  1900 //------------------------------Optimize---------------------------------------
  1901 // Given a graph, optimize it.
  1902 void Compile::Optimize() {
  1903   TracePhase t1("optimizer", &_t_optimizer, true);
  1905 #ifndef PRODUCT
  1906   if (env()->break_at_compile()) {
  1907     BREAKPOINT;
  1910 #endif
  1912   ResourceMark rm;
  1913   int          loop_opts_cnt;
  1915   NOT_PRODUCT( verify_graph_edges(); )
  1917   print_method("After Parsing");
  1920   // Iterative Global Value Numbering, including ideal transforms
  1921   // Initialize IterGVN with types and values from parse-time GVN
  1922   PhaseIterGVN igvn(initial_gvn());
  1924     NOT_PRODUCT( TracePhase t2("iterGVN", &_t_iterGVN, TimeCompiler); )
  1925     igvn.optimize();
  1928   print_method("Iter GVN 1", 2);
  1930   if (failing())  return;
  1932   inline_incrementally(igvn);
  1934   print_method("Incremental Inline", 2);
  1936   if (failing())  return;
  1938   // No more new expensive nodes will be added to the list from here
  1939   // so keep only the actual candidates for optimizations.
  1940   cleanup_expensive_nodes(igvn);
  1942   // Perform escape analysis
  1943   if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
  1944     if (has_loops()) {
  1945       // Cleanup graph (remove dead nodes).
  1946       TracePhase t2("idealLoop", &_t_idealLoop, true);
  1947       PhaseIdealLoop ideal_loop( igvn, false, true );
  1948       if (major_progress()) print_method("PhaseIdealLoop before EA", 2);
  1949       if (failing())  return;
  1951     ConnectionGraph::do_analysis(this, &igvn);
  1953     if (failing())  return;
  1955     // Optimize out fields loads from scalar replaceable allocations.
  1956     igvn.optimize();
  1957     print_method("Iter GVN after EA", 2);
  1959     if (failing())  return;
  1961     if (congraph() != NULL && macro_count() > 0) {
  1962       NOT_PRODUCT( TracePhase t2("macroEliminate", &_t_macroEliminate, TimeCompiler); )
  1963       PhaseMacroExpand mexp(igvn);
  1964       mexp.eliminate_macro_nodes();
  1965       igvn.set_delay_transform(false);
  1967       igvn.optimize();
  1968       print_method("Iter GVN after eliminating allocations and locks", 2);
  1970       if (failing())  return;
  1974   // Loop transforms on the ideal graph.  Range Check Elimination,
  1975   // peeling, unrolling, etc.
  1977   // Set loop opts counter
  1978   loop_opts_cnt = num_loop_opts();
  1979   if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
  1981       TracePhase t2("idealLoop", &_t_idealLoop, true);
  1982       PhaseIdealLoop ideal_loop( igvn, true );
  1983       loop_opts_cnt--;
  1984       if (major_progress()) print_method("PhaseIdealLoop 1", 2);
  1985       if (failing())  return;
  1987     // Loop opts pass if partial peeling occurred in previous pass
  1988     if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
  1989       TracePhase t3("idealLoop", &_t_idealLoop, true);
  1990       PhaseIdealLoop ideal_loop( igvn, false );
  1991       loop_opts_cnt--;
  1992       if (major_progress()) print_method("PhaseIdealLoop 2", 2);
  1993       if (failing())  return;
  1995     // Loop opts pass for loop-unrolling before CCP
  1996     if(major_progress() && (loop_opts_cnt > 0)) {
  1997       TracePhase t4("idealLoop", &_t_idealLoop, true);
  1998       PhaseIdealLoop ideal_loop( igvn, false );
  1999       loop_opts_cnt--;
  2000       if (major_progress()) print_method("PhaseIdealLoop 3", 2);
  2002     if (!failing()) {
  2003       // Verify that last round of loop opts produced a valid graph
  2004       NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
  2005       PhaseIdealLoop::verify(igvn);
  2008   if (failing())  return;
  2010   // Conditional Constant Propagation;
  2011   PhaseCCP ccp( &igvn );
  2012   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
  2014     TracePhase t2("ccp", &_t_ccp, true);
  2015     ccp.do_transform();
  2017   print_method("PhaseCPP 1", 2);
  2019   assert( true, "Break here to ccp.dump_old2new_map()");
  2021   // Iterative Global Value Numbering, including ideal transforms
  2023     NOT_PRODUCT( TracePhase t2("iterGVN2", &_t_iterGVN2, TimeCompiler); )
  2024     igvn = ccp;
  2025     igvn.optimize();
  2028   print_method("Iter GVN 2", 2);
  2030   if (failing())  return;
  2032   // Loop transforms on the ideal graph.  Range Check Elimination,
  2033   // peeling, unrolling, etc.
  2034   if(loop_opts_cnt > 0) {
  2035     debug_only( int cnt = 0; );
  2036     while(major_progress() && (loop_opts_cnt > 0)) {
  2037       TracePhase t2("idealLoop", &_t_idealLoop, true);
  2038       assert( cnt++ < 40, "infinite cycle in loop optimization" );
  2039       PhaseIdealLoop ideal_loop( igvn, true);
  2040       loop_opts_cnt--;
  2041       if (major_progress()) print_method("PhaseIdealLoop iterations", 2);
  2042       if (failing())  return;
  2047     // Verify that all previous optimizations produced a valid graph
  2048     // at least to this point, even if no loop optimizations were done.
  2049     NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
  2050     PhaseIdealLoop::verify(igvn);
  2054     NOT_PRODUCT( TracePhase t2("macroExpand", &_t_macroExpand, TimeCompiler); )
  2055     PhaseMacroExpand  mex(igvn);
  2056     if (mex.expand_macro_nodes()) {
  2057       assert(failing(), "must bail out w/ explicit message");
  2058       return;
  2062  } // (End scope of igvn; run destructor if necessary for asserts.)
  2064   dump_inlining();
  2065   // A method with only infinite loops has no edges entering loops from root
  2067     NOT_PRODUCT( TracePhase t2("graphReshape", &_t_graphReshaping, TimeCompiler); )
  2068     if (final_graph_reshaping()) {
  2069       assert(failing(), "must bail out w/ explicit message");
  2070       return;
  2074   print_method("Optimize finished", 2);
  2078 //------------------------------Code_Gen---------------------------------------
  2079 // Given a graph, generate code for it
  2080 void Compile::Code_Gen() {
  2081   if (failing())  return;
  2083   // Perform instruction selection.  You might think we could reclaim Matcher
  2084   // memory PDQ, but actually the Matcher is used in generating spill code.
  2085   // Internals of the Matcher (including some VectorSets) must remain live
  2086   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
  2087   // set a bit in reclaimed memory.
  2089   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
  2090   // nodes.  Mapping is only valid at the root of each matched subtree.
  2091   NOT_PRODUCT( verify_graph_edges(); )
  2093   Node_List proj_list;
  2094   Matcher m(proj_list);
  2095   _matcher = &m;
  2097     TracePhase t2("matcher", &_t_matcher, true);
  2098     m.match();
  2100   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
  2101   // nodes.  Mapping is only valid at the root of each matched subtree.
  2102   NOT_PRODUCT( verify_graph_edges(); )
  2104   // If you have too many nodes, or if matching has failed, bail out
  2105   check_node_count(0, "out of nodes matching instructions");
  2106   if (failing())  return;
  2108   // Build a proper-looking CFG
  2109   PhaseCFG cfg(node_arena(), root(), m);
  2110   _cfg = &cfg;
  2112     NOT_PRODUCT( TracePhase t2("scheduler", &_t_scheduler, TimeCompiler); )
  2113     cfg.Dominators();
  2114     if (failing())  return;
  2116     NOT_PRODUCT( verify_graph_edges(); )
  2118     cfg.Estimate_Block_Frequency();
  2119     cfg.GlobalCodeMotion(m,unique(),proj_list);
  2120     if (failing())  return;
  2122     print_method("Global code motion", 2);
  2124     NOT_PRODUCT( verify_graph_edges(); )
  2126     debug_only( cfg.verify(); )
  2128   NOT_PRODUCT( verify_graph_edges(); )
  2130   PhaseChaitin regalloc(unique(),cfg,m);
  2131   _regalloc = &regalloc;
  2133     TracePhase t2("regalloc", &_t_registerAllocation, true);
  2134     // Perform any platform dependent preallocation actions.  This is used,
  2135     // for example, to avoid taking an implicit null pointer exception
  2136     // using the frame pointer on win95.
  2137     _regalloc->pd_preallocate_hook();
  2139     // Perform register allocation.  After Chaitin, use-def chains are
  2140     // no longer accurate (at spill code) and so must be ignored.
  2141     // Node->LRG->reg mappings are still accurate.
  2142     _regalloc->Register_Allocate();
  2144     // Bail out if the allocator builds too many nodes
  2145     if (failing())  return;
  2148   // Prior to register allocation we kept empty basic blocks in case the
  2149   // the allocator needed a place to spill.  After register allocation we
  2150   // are not adding any new instructions.  If any basic block is empty, we
  2151   // can now safely remove it.
  2153     NOT_PRODUCT( TracePhase t2("blockOrdering", &_t_blockOrdering, TimeCompiler); )
  2154     cfg.remove_empty();
  2155     if (do_freq_based_layout()) {
  2156       PhaseBlockLayout layout(cfg);
  2157     } else {
  2158       cfg.set_loop_alignment();
  2160     cfg.fixup_flow();
  2163   // Perform any platform dependent postallocation verifications.
  2164   debug_only( _regalloc->pd_postallocate_verify_hook(); )
  2166   // Apply peephole optimizations
  2167   if( OptoPeephole ) {
  2168     NOT_PRODUCT( TracePhase t2("peephole", &_t_peephole, TimeCompiler); )
  2169     PhasePeephole peep( _regalloc, cfg);
  2170     peep.do_transform();
  2173   // Convert Nodes to instruction bits in a buffer
  2175     // %%%% workspace merge brought two timers together for one job
  2176     TracePhase t2a("output", &_t_output, true);
  2177     NOT_PRODUCT( TraceTime t2b(NULL, &_t_codeGeneration, TimeCompiler, false); )
  2178     Output();
  2181   print_method("Final Code");
  2183   // He's dead, Jim.
  2184   _cfg     = (PhaseCFG*)0xdeadbeef;
  2185   _regalloc = (PhaseChaitin*)0xdeadbeef;
  2189 //------------------------------dump_asm---------------------------------------
  2190 // Dump formatted assembly
  2191 #ifndef PRODUCT
  2192 void Compile::dump_asm(int *pcs, uint pc_limit) {
  2193   bool cut_short = false;
  2194   tty->print_cr("#");
  2195   tty->print("#  ");  _tf->dump();  tty->cr();
  2196   tty->print_cr("#");
  2198   // For all blocks
  2199   int pc = 0x0;                 // Program counter
  2200   char starts_bundle = ' ';
  2201   _regalloc->dump_frame();
  2203   Node *n = NULL;
  2204   for( uint i=0; i<_cfg->_num_blocks; i++ ) {
  2205     if (VMThread::should_terminate()) { cut_short = true; break; }
  2206     Block *b = _cfg->_blocks[i];
  2207     if (b->is_connector() && !Verbose) continue;
  2208     n = b->_nodes[0];
  2209     if (pcs && n->_idx < pc_limit)
  2210       tty->print("%3.3x   ", pcs[n->_idx]);
  2211     else
  2212       tty->print("      ");
  2213     b->dump_head( &_cfg->_bbs );
  2214     if (b->is_connector()) {
  2215       tty->print_cr("        # Empty connector block");
  2216     } else if (b->num_preds() == 2 && b->pred(1)->is_CatchProj() && b->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
  2217       tty->print_cr("        # Block is sole successor of call");
  2220     // For all instructions
  2221     Node *delay = NULL;
  2222     for( uint j = 0; j<b->_nodes.size(); j++ ) {
  2223       if (VMThread::should_terminate()) { cut_short = true; break; }
  2224       n = b->_nodes[j];
  2225       if (valid_bundle_info(n)) {
  2226         Bundle *bundle = node_bundling(n);
  2227         if (bundle->used_in_unconditional_delay()) {
  2228           delay = n;
  2229           continue;
  2231         if (bundle->starts_bundle())
  2232           starts_bundle = '+';
  2235       if (WizardMode) n->dump();
  2237       if( !n->is_Region() &&    // Dont print in the Assembly
  2238           !n->is_Phi() &&       // a few noisely useless nodes
  2239           !n->is_Proj() &&
  2240           !n->is_MachTemp() &&
  2241           !n->is_SafePointScalarObject() &&
  2242           !n->is_Catch() &&     // Would be nice to print exception table targets
  2243           !n->is_MergeMem() &&  // Not very interesting
  2244           !n->is_top() &&       // Debug info table constants
  2245           !(n->is_Con() && !n->is_Mach())// Debug info table constants
  2246           ) {
  2247         if (pcs && n->_idx < pc_limit)
  2248           tty->print("%3.3x", pcs[n->_idx]);
  2249         else
  2250           tty->print("   ");
  2251         tty->print(" %c ", starts_bundle);
  2252         starts_bundle = ' ';
  2253         tty->print("\t");
  2254         n->format(_regalloc, tty);
  2255         tty->cr();
  2258       // If we have an instruction with a delay slot, and have seen a delay,
  2259       // then back up and print it
  2260       if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
  2261         assert(delay != NULL, "no unconditional delay instruction");
  2262         if (WizardMode) delay->dump();
  2264         if (node_bundling(delay)->starts_bundle())
  2265           starts_bundle = '+';
  2266         if (pcs && n->_idx < pc_limit)
  2267           tty->print("%3.3x", pcs[n->_idx]);
  2268         else
  2269           tty->print("   ");
  2270         tty->print(" %c ", starts_bundle);
  2271         starts_bundle = ' ';
  2272         tty->print("\t");
  2273         delay->format(_regalloc, tty);
  2274         tty->print_cr("");
  2275         delay = NULL;
  2278       // Dump the exception table as well
  2279       if( n->is_Catch() && (Verbose || WizardMode) ) {
  2280         // Print the exception table for this offset
  2281         _handler_table.print_subtable_for(pc);
  2285     if (pcs && n->_idx < pc_limit)
  2286       tty->print_cr("%3.3x", pcs[n->_idx]);
  2287     else
  2288       tty->print_cr("");
  2290     assert(cut_short || delay == NULL, "no unconditional delay branch");
  2292   } // End of per-block dump
  2293   tty->print_cr("");
  2295   if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
  2297 #endif
  2299 //------------------------------Final_Reshape_Counts---------------------------
  2300 // This class defines counters to help identify when a method
  2301 // may/must be executed using hardware with only 24-bit precision.
  2302 struct Final_Reshape_Counts : public StackObj {
  2303   int  _call_count;             // count non-inlined 'common' calls
  2304   int  _float_count;            // count float ops requiring 24-bit precision
  2305   int  _double_count;           // count double ops requiring more precision
  2306   int  _java_call_count;        // count non-inlined 'java' calls
  2307   int  _inner_loop_count;       // count loops which need alignment
  2308   VectorSet _visited;           // Visitation flags
  2309   Node_List _tests;             // Set of IfNodes & PCTableNodes
  2311   Final_Reshape_Counts() :
  2312     _call_count(0), _float_count(0), _double_count(0),
  2313     _java_call_count(0), _inner_loop_count(0),
  2314     _visited( Thread::current()->resource_area() ) { }
  2316   void inc_call_count  () { _call_count  ++; }
  2317   void inc_float_count () { _float_count ++; }
  2318   void inc_double_count() { _double_count++; }
  2319   void inc_java_call_count() { _java_call_count++; }
  2320   void inc_inner_loop_count() { _inner_loop_count++; }
  2322   int  get_call_count  () const { return _call_count  ; }
  2323   int  get_float_count () const { return _float_count ; }
  2324   int  get_double_count() const { return _double_count; }
  2325   int  get_java_call_count() const { return _java_call_count; }
  2326   int  get_inner_loop_count() const { return _inner_loop_count; }
  2327 };
  2329 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
  2330   ciInstanceKlass *k = tp->klass()->as_instance_klass();
  2331   // Make sure the offset goes inside the instance layout.
  2332   return k->contains_field_offset(tp->offset());
  2333   // Note that OffsetBot and OffsetTop are very negative.
  2336 // Eliminate trivially redundant StoreCMs and accumulate their
  2337 // precedence edges.
  2338 void Compile::eliminate_redundant_card_marks(Node* n) {
  2339   assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
  2340   if (n->in(MemNode::Address)->outcnt() > 1) {
  2341     // There are multiple users of the same address so it might be
  2342     // possible to eliminate some of the StoreCMs
  2343     Node* mem = n->in(MemNode::Memory);
  2344     Node* adr = n->in(MemNode::Address);
  2345     Node* val = n->in(MemNode::ValueIn);
  2346     Node* prev = n;
  2347     bool done = false;
  2348     // Walk the chain of StoreCMs eliminating ones that match.  As
  2349     // long as it's a chain of single users then the optimization is
  2350     // safe.  Eliminating partially redundant StoreCMs would require
  2351     // cloning copies down the other paths.
  2352     while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
  2353       if (adr == mem->in(MemNode::Address) &&
  2354           val == mem->in(MemNode::ValueIn)) {
  2355         // redundant StoreCM
  2356         if (mem->req() > MemNode::OopStore) {
  2357           // Hasn't been processed by this code yet.
  2358           n->add_prec(mem->in(MemNode::OopStore));
  2359         } else {
  2360           // Already converted to precedence edge
  2361           for (uint i = mem->req(); i < mem->len(); i++) {
  2362             // Accumulate any precedence edges
  2363             if (mem->in(i) != NULL) {
  2364               n->add_prec(mem->in(i));
  2367           // Everything above this point has been processed.
  2368           done = true;
  2370         // Eliminate the previous StoreCM
  2371         prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
  2372         assert(mem->outcnt() == 0, "should be dead");
  2373         mem->disconnect_inputs(NULL, this);
  2374       } else {
  2375         prev = mem;
  2377       mem = prev->in(MemNode::Memory);
  2382 //------------------------------final_graph_reshaping_impl----------------------
  2383 // Implement items 1-5 from final_graph_reshaping below.
  2384 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
  2386   if ( n->outcnt() == 0 ) return; // dead node
  2387   uint nop = n->Opcode();
  2389   // Check for 2-input instruction with "last use" on right input.
  2390   // Swap to left input.  Implements item (2).
  2391   if( n->req() == 3 &&          // two-input instruction
  2392       n->in(1)->outcnt() > 1 && // left use is NOT a last use
  2393       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
  2394       n->in(2)->outcnt() == 1 &&// right use IS a last use
  2395       !n->in(2)->is_Con() ) {   // right use is not a constant
  2396     // Check for commutative opcode
  2397     switch( nop ) {
  2398     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
  2399     case Op_MaxI:  case Op_MinI:
  2400     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
  2401     case Op_AndL:  case Op_XorL:  case Op_OrL:
  2402     case Op_AndI:  case Op_XorI:  case Op_OrI: {
  2403       // Move "last use" input to left by swapping inputs
  2404       n->swap_edges(1, 2);
  2405       break;
  2407     default:
  2408       break;
  2412 #ifdef ASSERT
  2413   if( n->is_Mem() ) {
  2414     int alias_idx = get_alias_index(n->as_Mem()->adr_type());
  2415     assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
  2416             // oop will be recorded in oop map if load crosses safepoint
  2417             n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
  2418                              LoadNode::is_immutable_value(n->in(MemNode::Address))),
  2419             "raw memory operations should have control edge");
  2421 #endif
  2422   // Count FPU ops and common calls, implements item (3)
  2423   switch( nop ) {
  2424   // Count all float operations that may use FPU
  2425   case Op_AddF:
  2426   case Op_SubF:
  2427   case Op_MulF:
  2428   case Op_DivF:
  2429   case Op_NegF:
  2430   case Op_ModF:
  2431   case Op_ConvI2F:
  2432   case Op_ConF:
  2433   case Op_CmpF:
  2434   case Op_CmpF3:
  2435   // case Op_ConvL2F: // longs are split into 32-bit halves
  2436     frc.inc_float_count();
  2437     break;
  2439   case Op_ConvF2D:
  2440   case Op_ConvD2F:
  2441     frc.inc_float_count();
  2442     frc.inc_double_count();
  2443     break;
  2445   // Count all double operations that may use FPU
  2446   case Op_AddD:
  2447   case Op_SubD:
  2448   case Op_MulD:
  2449   case Op_DivD:
  2450   case Op_NegD:
  2451   case Op_ModD:
  2452   case Op_ConvI2D:
  2453   case Op_ConvD2I:
  2454   // case Op_ConvL2D: // handled by leaf call
  2455   // case Op_ConvD2L: // handled by leaf call
  2456   case Op_ConD:
  2457   case Op_CmpD:
  2458   case Op_CmpD3:
  2459     frc.inc_double_count();
  2460     break;
  2461   case Op_Opaque1:              // Remove Opaque Nodes before matching
  2462   case Op_Opaque2:              // Remove Opaque Nodes before matching
  2463     n->subsume_by(n->in(1), this);
  2464     break;
  2465   case Op_CallStaticJava:
  2466   case Op_CallJava:
  2467   case Op_CallDynamicJava:
  2468     frc.inc_java_call_count(); // Count java call site;
  2469   case Op_CallRuntime:
  2470   case Op_CallLeaf:
  2471   case Op_CallLeafNoFP: {
  2472     assert( n->is_Call(), "" );
  2473     CallNode *call = n->as_Call();
  2474     // Count call sites where the FP mode bit would have to be flipped.
  2475     // Do not count uncommon runtime calls:
  2476     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
  2477     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
  2478     if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
  2479       frc.inc_call_count();   // Count the call site
  2480     } else {                  // See if uncommon argument is shared
  2481       Node *n = call->in(TypeFunc::Parms);
  2482       int nop = n->Opcode();
  2483       // Clone shared simple arguments to uncommon calls, item (1).
  2484       if( n->outcnt() > 1 &&
  2485           !n->is_Proj() &&
  2486           nop != Op_CreateEx &&
  2487           nop != Op_CheckCastPP &&
  2488           nop != Op_DecodeN &&
  2489           nop != Op_DecodeNKlass &&
  2490           !n->is_Mem() ) {
  2491         Node *x = n->clone();
  2492         call->set_req( TypeFunc::Parms, x );
  2495     break;
  2498   case Op_StoreD:
  2499   case Op_LoadD:
  2500   case Op_LoadD_unaligned:
  2501     frc.inc_double_count();
  2502     goto handle_mem;
  2503   case Op_StoreF:
  2504   case Op_LoadF:
  2505     frc.inc_float_count();
  2506     goto handle_mem;
  2508   case Op_StoreCM:
  2510       // Convert OopStore dependence into precedence edge
  2511       Node* prec = n->in(MemNode::OopStore);
  2512       n->del_req(MemNode::OopStore);
  2513       n->add_prec(prec);
  2514       eliminate_redundant_card_marks(n);
  2517     // fall through
  2519   case Op_StoreB:
  2520   case Op_StoreC:
  2521   case Op_StorePConditional:
  2522   case Op_StoreI:
  2523   case Op_StoreL:
  2524   case Op_StoreIConditional:
  2525   case Op_StoreLConditional:
  2526   case Op_CompareAndSwapI:
  2527   case Op_CompareAndSwapL:
  2528   case Op_CompareAndSwapP:
  2529   case Op_CompareAndSwapN:
  2530   case Op_GetAndAddI:
  2531   case Op_GetAndAddL:
  2532   case Op_GetAndSetI:
  2533   case Op_GetAndSetL:
  2534   case Op_GetAndSetP:
  2535   case Op_GetAndSetN:
  2536   case Op_StoreP:
  2537   case Op_StoreN:
  2538   case Op_StoreNKlass:
  2539   case Op_LoadB:
  2540   case Op_LoadUB:
  2541   case Op_LoadUS:
  2542   case Op_LoadI:
  2543   case Op_LoadKlass:
  2544   case Op_LoadNKlass:
  2545   case Op_LoadL:
  2546   case Op_LoadL_unaligned:
  2547   case Op_LoadPLocked:
  2548   case Op_LoadP:
  2549   case Op_LoadN:
  2550   case Op_LoadRange:
  2551   case Op_LoadS: {
  2552   handle_mem:
  2553 #ifdef ASSERT
  2554     if( VerifyOptoOopOffsets ) {
  2555       assert( n->is_Mem(), "" );
  2556       MemNode *mem  = (MemNode*)n;
  2557       // Check to see if address types have grounded out somehow.
  2558       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
  2559       assert( !tp || oop_offset_is_sane(tp), "" );
  2561 #endif
  2562     break;
  2565   case Op_AddP: {               // Assert sane base pointers
  2566     Node *addp = n->in(AddPNode::Address);
  2567     assert( !addp->is_AddP() ||
  2568             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
  2569             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
  2570             "Base pointers must match" );
  2571 #ifdef _LP64
  2572     if ((UseCompressedOops || UseCompressedKlassPointers) &&
  2573         addp->Opcode() == Op_ConP &&
  2574         addp == n->in(AddPNode::Base) &&
  2575         n->in(AddPNode::Offset)->is_Con()) {
  2576       // Use addressing with narrow klass to load with offset on x86.
  2577       // On sparc loading 32-bits constant and decoding it have less
  2578       // instructions (4) then load 64-bits constant (7).
  2579       // Do this transformation here since IGVN will convert ConN back to ConP.
  2580       const Type* t = addp->bottom_type();
  2581       if (t->isa_oopptr() || t->isa_klassptr()) {
  2582         Node* nn = NULL;
  2584         int op = t->isa_oopptr() ? Op_ConN : Op_ConNKlass;
  2586         // Look for existing ConN node of the same exact type.
  2587         Node* r  = root();
  2588         uint cnt = r->outcnt();
  2589         for (uint i = 0; i < cnt; i++) {
  2590           Node* m = r->raw_out(i);
  2591           if (m!= NULL && m->Opcode() == op &&
  2592               m->bottom_type()->make_ptr() == t) {
  2593             nn = m;
  2594             break;
  2597         if (nn != NULL) {
  2598           // Decode a narrow oop to match address
  2599           // [R12 + narrow_oop_reg<<3 + offset]
  2600           if (t->isa_oopptr()) {
  2601             nn = new (this) DecodeNNode(nn, t);
  2602           } else {
  2603             nn = new (this) DecodeNKlassNode(nn, t);
  2605           n->set_req(AddPNode::Base, nn);
  2606           n->set_req(AddPNode::Address, nn);
  2607           if (addp->outcnt() == 0) {
  2608             addp->disconnect_inputs(NULL, this);
  2613 #endif
  2614     break;
  2617 #ifdef _LP64
  2618   case Op_CastPP:
  2619     if (n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
  2620       Node* in1 = n->in(1);
  2621       const Type* t = n->bottom_type();
  2622       Node* new_in1 = in1->clone();
  2623       new_in1->as_DecodeN()->set_type(t);
  2625       if (!Matcher::narrow_oop_use_complex_address()) {
  2626         //
  2627         // x86, ARM and friends can handle 2 adds in addressing mode
  2628         // and Matcher can fold a DecodeN node into address by using
  2629         // a narrow oop directly and do implicit NULL check in address:
  2630         //
  2631         // [R12 + narrow_oop_reg<<3 + offset]
  2632         // NullCheck narrow_oop_reg
  2633         //
  2634         // On other platforms (Sparc) we have to keep new DecodeN node and
  2635         // use it to do implicit NULL check in address:
  2636         //
  2637         // decode_not_null narrow_oop_reg, base_reg
  2638         // [base_reg + offset]
  2639         // NullCheck base_reg
  2640         //
  2641         // Pin the new DecodeN node to non-null path on these platform (Sparc)
  2642         // to keep the information to which NULL check the new DecodeN node
  2643         // corresponds to use it as value in implicit_null_check().
  2644         //
  2645         new_in1->set_req(0, n->in(0));
  2648       n->subsume_by(new_in1, this);
  2649       if (in1->outcnt() == 0) {
  2650         in1->disconnect_inputs(NULL, this);
  2653     break;
  2655   case Op_CmpP:
  2656     // Do this transformation here to preserve CmpPNode::sub() and
  2657     // other TypePtr related Ideal optimizations (for example, ptr nullness).
  2658     if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
  2659       Node* in1 = n->in(1);
  2660       Node* in2 = n->in(2);
  2661       if (!in1->is_DecodeNarrowPtr()) {
  2662         in2 = in1;
  2663         in1 = n->in(2);
  2665       assert(in1->is_DecodeNarrowPtr(), "sanity");
  2667       Node* new_in2 = NULL;
  2668       if (in2->is_DecodeNarrowPtr()) {
  2669         assert(in2->Opcode() == in1->Opcode(), "must be same node type");
  2670         new_in2 = in2->in(1);
  2671       } else if (in2->Opcode() == Op_ConP) {
  2672         const Type* t = in2->bottom_type();
  2673         if (t == TypePtr::NULL_PTR) {
  2674           assert(in1->is_DecodeN(), "compare klass to null?");
  2675           // Don't convert CmpP null check into CmpN if compressed
  2676           // oops implicit null check is not generated.
  2677           // This will allow to generate normal oop implicit null check.
  2678           if (Matcher::gen_narrow_oop_implicit_null_checks())
  2679             new_in2 = ConNode::make(this, TypeNarrowOop::NULL_PTR);
  2680           //
  2681           // This transformation together with CastPP transformation above
  2682           // will generated code for implicit NULL checks for compressed oops.
  2683           //
  2684           // The original code after Optimize()
  2685           //
  2686           //    LoadN memory, narrow_oop_reg
  2687           //    decode narrow_oop_reg, base_reg
  2688           //    CmpP base_reg, NULL
  2689           //    CastPP base_reg // NotNull
  2690           //    Load [base_reg + offset], val_reg
  2691           //
  2692           // after these transformations will be
  2693           //
  2694           //    LoadN memory, narrow_oop_reg
  2695           //    CmpN narrow_oop_reg, NULL
  2696           //    decode_not_null narrow_oop_reg, base_reg
  2697           //    Load [base_reg + offset], val_reg
  2698           //
  2699           // and the uncommon path (== NULL) will use narrow_oop_reg directly
  2700           // since narrow oops can be used in debug info now (see the code in
  2701           // final_graph_reshaping_walk()).
  2702           //
  2703           // At the end the code will be matched to
  2704           // on x86:
  2705           //
  2706           //    Load_narrow_oop memory, narrow_oop_reg
  2707           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
  2708           //    NullCheck narrow_oop_reg
  2709           //
  2710           // and on sparc:
  2711           //
  2712           //    Load_narrow_oop memory, narrow_oop_reg
  2713           //    decode_not_null narrow_oop_reg, base_reg
  2714           //    Load [base_reg + offset], val_reg
  2715           //    NullCheck base_reg
  2716           //
  2717         } else if (t->isa_oopptr()) {
  2718           new_in2 = ConNode::make(this, t->make_narrowoop());
  2719         } else if (t->isa_klassptr()) {
  2720           new_in2 = ConNode::make(this, t->make_narrowklass());
  2723       if (new_in2 != NULL) {
  2724         Node* cmpN = new (this) CmpNNode(in1->in(1), new_in2);
  2725         n->subsume_by(cmpN, this);
  2726         if (in1->outcnt() == 0) {
  2727           in1->disconnect_inputs(NULL, this);
  2729         if (in2->outcnt() == 0) {
  2730           in2->disconnect_inputs(NULL, this);
  2734     break;
  2736   case Op_DecodeN:
  2737   case Op_DecodeNKlass:
  2738     assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
  2739     // DecodeN could be pinned when it can't be fold into
  2740     // an address expression, see the code for Op_CastPP above.
  2741     assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
  2742     break;
  2744   case Op_EncodeP:
  2745   case Op_EncodePKlass: {
  2746     Node* in1 = n->in(1);
  2747     if (in1->is_DecodeNarrowPtr()) {
  2748       n->subsume_by(in1->in(1), this);
  2749     } else if (in1->Opcode() == Op_ConP) {
  2750       const Type* t = in1->bottom_type();
  2751       if (t == TypePtr::NULL_PTR) {
  2752         assert(t->isa_oopptr(), "null klass?");
  2753         n->subsume_by(ConNode::make(this, TypeNarrowOop::NULL_PTR), this);
  2754       } else if (t->isa_oopptr()) {
  2755         n->subsume_by(ConNode::make(this, t->make_narrowoop()), this);
  2756       } else if (t->isa_klassptr()) {
  2757         n->subsume_by(ConNode::make(this, t->make_narrowklass()), this);
  2760     if (in1->outcnt() == 0) {
  2761       in1->disconnect_inputs(NULL, this);
  2763     break;
  2766   case Op_Proj: {
  2767     if (OptimizeStringConcat) {
  2768       ProjNode* p = n->as_Proj();
  2769       if (p->_is_io_use) {
  2770         // Separate projections were used for the exception path which
  2771         // are normally removed by a late inline.  If it wasn't inlined
  2772         // then they will hang around and should just be replaced with
  2773         // the original one.
  2774         Node* proj = NULL;
  2775         // Replace with just one
  2776         for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
  2777           Node *use = i.get();
  2778           if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
  2779             proj = use;
  2780             break;
  2783         assert(proj != NULL, "must be found");
  2784         p->subsume_by(proj, this);
  2787     break;
  2790   case Op_Phi:
  2791     if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
  2792       // The EncodeP optimization may create Phi with the same edges
  2793       // for all paths. It is not handled well by Register Allocator.
  2794       Node* unique_in = n->in(1);
  2795       assert(unique_in != NULL, "");
  2796       uint cnt = n->req();
  2797       for (uint i = 2; i < cnt; i++) {
  2798         Node* m = n->in(i);
  2799         assert(m != NULL, "");
  2800         if (unique_in != m)
  2801           unique_in = NULL;
  2803       if (unique_in != NULL) {
  2804         n->subsume_by(unique_in, this);
  2807     break;
  2809 #endif
  2811   case Op_ModI:
  2812     if (UseDivMod) {
  2813       // Check if a%b and a/b both exist
  2814       Node* d = n->find_similar(Op_DivI);
  2815       if (d) {
  2816         // Replace them with a fused divmod if supported
  2817         if (Matcher::has_match_rule(Op_DivModI)) {
  2818           DivModINode* divmod = DivModINode::make(this, n);
  2819           d->subsume_by(divmod->div_proj(), this);
  2820           n->subsume_by(divmod->mod_proj(), this);
  2821         } else {
  2822           // replace a%b with a-((a/b)*b)
  2823           Node* mult = new (this) MulINode(d, d->in(2));
  2824           Node* sub  = new (this) SubINode(d->in(1), mult);
  2825           n->subsume_by(sub, this);
  2829     break;
  2831   case Op_ModL:
  2832     if (UseDivMod) {
  2833       // Check if a%b and a/b both exist
  2834       Node* d = n->find_similar(Op_DivL);
  2835       if (d) {
  2836         // Replace them with a fused divmod if supported
  2837         if (Matcher::has_match_rule(Op_DivModL)) {
  2838           DivModLNode* divmod = DivModLNode::make(this, n);
  2839           d->subsume_by(divmod->div_proj(), this);
  2840           n->subsume_by(divmod->mod_proj(), this);
  2841         } else {
  2842           // replace a%b with a-((a/b)*b)
  2843           Node* mult = new (this) MulLNode(d, d->in(2));
  2844           Node* sub  = new (this) SubLNode(d->in(1), mult);
  2845           n->subsume_by(sub, this);
  2849     break;
  2851   case Op_LoadVector:
  2852   case Op_StoreVector:
  2853     break;
  2855   case Op_PackB:
  2856   case Op_PackS:
  2857   case Op_PackI:
  2858   case Op_PackF:
  2859   case Op_PackL:
  2860   case Op_PackD:
  2861     if (n->req()-1 > 2) {
  2862       // Replace many operand PackNodes with a binary tree for matching
  2863       PackNode* p = (PackNode*) n;
  2864       Node* btp = p->binary_tree_pack(this, 1, n->req());
  2865       n->subsume_by(btp, this);
  2867     break;
  2868   case Op_Loop:
  2869   case Op_CountedLoop:
  2870     if (n->as_Loop()->is_inner_loop()) {
  2871       frc.inc_inner_loop_count();
  2873     break;
  2874   case Op_LShiftI:
  2875   case Op_RShiftI:
  2876   case Op_URShiftI:
  2877   case Op_LShiftL:
  2878   case Op_RShiftL:
  2879   case Op_URShiftL:
  2880     if (Matcher::need_masked_shift_count) {
  2881       // The cpu's shift instructions don't restrict the count to the
  2882       // lower 5/6 bits. We need to do the masking ourselves.
  2883       Node* in2 = n->in(2);
  2884       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
  2885       const TypeInt* t = in2->find_int_type();
  2886       if (t != NULL && t->is_con()) {
  2887         juint shift = t->get_con();
  2888         if (shift > mask) { // Unsigned cmp
  2889           n->set_req(2, ConNode::make(this, TypeInt::make(shift & mask)));
  2891       } else {
  2892         if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
  2893           Node* shift = new (this) AndINode(in2, ConNode::make(this, TypeInt::make(mask)));
  2894           n->set_req(2, shift);
  2897       if (in2->outcnt() == 0) { // Remove dead node
  2898         in2->disconnect_inputs(NULL, this);
  2901     break;
  2902   case Op_MemBarStoreStore:
  2903     // Break the link with AllocateNode: it is no longer useful and
  2904     // confuses register allocation.
  2905     if (n->req() > MemBarNode::Precedent) {
  2906       n->set_req(MemBarNode::Precedent, top());
  2908     break;
  2909   default:
  2910     assert( !n->is_Call(), "" );
  2911     assert( !n->is_Mem(), "" );
  2912     break;
  2915   // Collect CFG split points
  2916   if (n->is_MultiBranch())
  2917     frc._tests.push(n);
  2920 //------------------------------final_graph_reshaping_walk---------------------
  2921 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
  2922 // requires that the walk visits a node's inputs before visiting the node.
  2923 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
  2924   ResourceArea *area = Thread::current()->resource_area();
  2925   Unique_Node_List sfpt(area);
  2927   frc._visited.set(root->_idx); // first, mark node as visited
  2928   uint cnt = root->req();
  2929   Node *n = root;
  2930   uint  i = 0;
  2931   while (true) {
  2932     if (i < cnt) {
  2933       // Place all non-visited non-null inputs onto stack
  2934       Node* m = n->in(i);
  2935       ++i;
  2936       if (m != NULL && !frc._visited.test_set(m->_idx)) {
  2937         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL)
  2938           sfpt.push(m);
  2939         cnt = m->req();
  2940         nstack.push(n, i); // put on stack parent and next input's index
  2941         n = m;
  2942         i = 0;
  2944     } else {
  2945       // Now do post-visit work
  2946       final_graph_reshaping_impl( n, frc );
  2947       if (nstack.is_empty())
  2948         break;             // finished
  2949       n = nstack.node();   // Get node from stack
  2950       cnt = n->req();
  2951       i = nstack.index();
  2952       nstack.pop();        // Shift to the next node on stack
  2956   // Skip next transformation if compressed oops are not used.
  2957   if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
  2958       (!UseCompressedOops && !UseCompressedKlassPointers))
  2959     return;
  2961   // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
  2962   // It could be done for an uncommon traps or any safepoints/calls
  2963   // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
  2964   while (sfpt.size() > 0) {
  2965     n = sfpt.pop();
  2966     JVMState *jvms = n->as_SafePoint()->jvms();
  2967     assert(jvms != NULL, "sanity");
  2968     int start = jvms->debug_start();
  2969     int end   = n->req();
  2970     bool is_uncommon = (n->is_CallStaticJava() &&
  2971                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
  2972     for (int j = start; j < end; j++) {
  2973       Node* in = n->in(j);
  2974       if (in->is_DecodeNarrowPtr()) {
  2975         bool safe_to_skip = true;
  2976         if (!is_uncommon ) {
  2977           // Is it safe to skip?
  2978           for (uint i = 0; i < in->outcnt(); i++) {
  2979             Node* u = in->raw_out(i);
  2980             if (!u->is_SafePoint() ||
  2981                  u->is_Call() && u->as_Call()->has_non_debug_use(n)) {
  2982               safe_to_skip = false;
  2986         if (safe_to_skip) {
  2987           n->set_req(j, in->in(1));
  2989         if (in->outcnt() == 0) {
  2990           in->disconnect_inputs(NULL, this);
  2997 //------------------------------final_graph_reshaping--------------------------
  2998 // Final Graph Reshaping.
  2999 //
  3000 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
  3001 //     and not commoned up and forced early.  Must come after regular
  3002 //     optimizations to avoid GVN undoing the cloning.  Clone constant
  3003 //     inputs to Loop Phis; these will be split by the allocator anyways.
  3004 //     Remove Opaque nodes.
  3005 // (2) Move last-uses by commutative operations to the left input to encourage
  3006 //     Intel update-in-place two-address operations and better register usage
  3007 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
  3008 //     calls canonicalizing them back.
  3009 // (3) Count the number of double-precision FP ops, single-precision FP ops
  3010 //     and call sites.  On Intel, we can get correct rounding either by
  3011 //     forcing singles to memory (requires extra stores and loads after each
  3012 //     FP bytecode) or we can set a rounding mode bit (requires setting and
  3013 //     clearing the mode bit around call sites).  The mode bit is only used
  3014 //     if the relative frequency of single FP ops to calls is low enough.
  3015 //     This is a key transform for SPEC mpeg_audio.
  3016 // (4) Detect infinite loops; blobs of code reachable from above but not
  3017 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
  3018 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
  3019 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
  3020 //     Detection is by looking for IfNodes where only 1 projection is
  3021 //     reachable from below or CatchNodes missing some targets.
  3022 // (5) Assert for insane oop offsets in debug mode.
  3024 bool Compile::final_graph_reshaping() {
  3025   // an infinite loop may have been eliminated by the optimizer,
  3026   // in which case the graph will be empty.
  3027   if (root()->req() == 1) {
  3028     record_method_not_compilable("trivial infinite loop");
  3029     return true;
  3032   // Expensive nodes have their control input set to prevent the GVN
  3033   // from freely commoning them. There's no GVN beyond this point so
  3034   // no need to keep the control input. We want the expensive nodes to
  3035   // be freely moved to the least frequent code path by gcm.
  3036   assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
  3037   for (int i = 0; i < expensive_count(); i++) {
  3038     _expensive_nodes->at(i)->set_req(0, NULL);
  3041   Final_Reshape_Counts frc;
  3043   // Visit everybody reachable!
  3044   // Allocate stack of size C->unique()/2 to avoid frequent realloc
  3045   Node_Stack nstack(unique() >> 1);
  3046   final_graph_reshaping_walk(nstack, root(), frc);
  3048   // Check for unreachable (from below) code (i.e., infinite loops).
  3049   for( uint i = 0; i < frc._tests.size(); i++ ) {
  3050     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
  3051     // Get number of CFG targets.
  3052     // Note that PCTables include exception targets after calls.
  3053     uint required_outcnt = n->required_outcnt();
  3054     if (n->outcnt() != required_outcnt) {
  3055       // Check for a few special cases.  Rethrow Nodes never take the
  3056       // 'fall-thru' path, so expected kids is 1 less.
  3057       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
  3058         if (n->in(0)->in(0)->is_Call()) {
  3059           CallNode *call = n->in(0)->in(0)->as_Call();
  3060           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
  3061             required_outcnt--;      // Rethrow always has 1 less kid
  3062           } else if (call->req() > TypeFunc::Parms &&
  3063                      call->is_CallDynamicJava()) {
  3064             // Check for null receiver. In such case, the optimizer has
  3065             // detected that the virtual call will always result in a null
  3066             // pointer exception. The fall-through projection of this CatchNode
  3067             // will not be populated.
  3068             Node *arg0 = call->in(TypeFunc::Parms);
  3069             if (arg0->is_Type() &&
  3070                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
  3071               required_outcnt--;
  3073           } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
  3074                      call->req() > TypeFunc::Parms+1 &&
  3075                      call->is_CallStaticJava()) {
  3076             // Check for negative array length. In such case, the optimizer has
  3077             // detected that the allocation attempt will always result in an
  3078             // exception. There is no fall-through projection of this CatchNode .
  3079             Node *arg1 = call->in(TypeFunc::Parms+1);
  3080             if (arg1->is_Type() &&
  3081                 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
  3082               required_outcnt--;
  3087       // Recheck with a better notion of 'required_outcnt'
  3088       if (n->outcnt() != required_outcnt) {
  3089         record_method_not_compilable("malformed control flow");
  3090         return true;            // Not all targets reachable!
  3093     // Check that I actually visited all kids.  Unreached kids
  3094     // must be infinite loops.
  3095     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
  3096       if (!frc._visited.test(n->fast_out(j)->_idx)) {
  3097         record_method_not_compilable("infinite loop");
  3098         return true;            // Found unvisited kid; must be unreach
  3102   // If original bytecodes contained a mixture of floats and doubles
  3103   // check if the optimizer has made it homogenous, item (3).
  3104   if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
  3105       frc.get_float_count() > 32 &&
  3106       frc.get_double_count() == 0 &&
  3107       (10 * frc.get_call_count() < frc.get_float_count()) ) {
  3108     set_24_bit_selection_and_mode( false,  true );
  3111   set_java_calls(frc.get_java_call_count());
  3112   set_inner_loops(frc.get_inner_loop_count());
  3114   // No infinite loops, no reason to bail out.
  3115   return false;
  3118 //-----------------------------too_many_traps----------------------------------
  3119 // Report if there are too many traps at the current method and bci.
  3120 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
  3121 bool Compile::too_many_traps(ciMethod* method,
  3122                              int bci,
  3123                              Deoptimization::DeoptReason reason) {
  3124   ciMethodData* md = method->method_data();
  3125   if (md->is_empty()) {
  3126     // Assume the trap has not occurred, or that it occurred only
  3127     // because of a transient condition during start-up in the interpreter.
  3128     return false;
  3130   if (md->has_trap_at(bci, reason) != 0) {
  3131     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
  3132     // Also, if there are multiple reasons, or if there is no per-BCI record,
  3133     // assume the worst.
  3134     if (log())
  3135       log()->elem("observe trap='%s' count='%d'",
  3136                   Deoptimization::trap_reason_name(reason),
  3137                   md->trap_count(reason));
  3138     return true;
  3139   } else {
  3140     // Ignore method/bci and see if there have been too many globally.
  3141     return too_many_traps(reason, md);
  3145 // Less-accurate variant which does not require a method and bci.
  3146 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
  3147                              ciMethodData* logmd) {
  3148  if (trap_count(reason) >= (uint)PerMethodTrapLimit) {
  3149     // Too many traps globally.
  3150     // Note that we use cumulative trap_count, not just md->trap_count.
  3151     if (log()) {
  3152       int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
  3153       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
  3154                   Deoptimization::trap_reason_name(reason),
  3155                   mcount, trap_count(reason));
  3157     return true;
  3158   } else {
  3159     // The coast is clear.
  3160     return false;
  3164 //--------------------------too_many_recompiles--------------------------------
  3165 // Report if there are too many recompiles at the current method and bci.
  3166 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
  3167 // Is not eager to return true, since this will cause the compiler to use
  3168 // Action_none for a trap point, to avoid too many recompilations.
  3169 bool Compile::too_many_recompiles(ciMethod* method,
  3170                                   int bci,
  3171                                   Deoptimization::DeoptReason reason) {
  3172   ciMethodData* md = method->method_data();
  3173   if (md->is_empty()) {
  3174     // Assume the trap has not occurred, or that it occurred only
  3175     // because of a transient condition during start-up in the interpreter.
  3176     return false;
  3178   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
  3179   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
  3180   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
  3181   Deoptimization::DeoptReason per_bc_reason
  3182     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
  3183   if ((per_bc_reason == Deoptimization::Reason_none
  3184        || md->has_trap_at(bci, reason) != 0)
  3185       // The trap frequency measure we care about is the recompile count:
  3186       && md->trap_recompiled_at(bci)
  3187       && md->overflow_recompile_count() >= bc_cutoff) {
  3188     // Do not emit a trap here if it has already caused recompilations.
  3189     // Also, if there are multiple reasons, or if there is no per-BCI record,
  3190     // assume the worst.
  3191     if (log())
  3192       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
  3193                   Deoptimization::trap_reason_name(reason),
  3194                   md->trap_count(reason),
  3195                   md->overflow_recompile_count());
  3196     return true;
  3197   } else if (trap_count(reason) != 0
  3198              && decompile_count() >= m_cutoff) {
  3199     // Too many recompiles globally, and we have seen this sort of trap.
  3200     // Use cumulative decompile_count, not just md->decompile_count.
  3201     if (log())
  3202       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
  3203                   Deoptimization::trap_reason_name(reason),
  3204                   md->trap_count(reason), trap_count(reason),
  3205                   md->decompile_count(), decompile_count());
  3206     return true;
  3207   } else {
  3208     // The coast is clear.
  3209     return false;
  3214 #ifndef PRODUCT
  3215 //------------------------------verify_graph_edges---------------------------
  3216 // Walk the Graph and verify that there is a one-to-one correspondence
  3217 // between Use-Def edges and Def-Use edges in the graph.
  3218 void Compile::verify_graph_edges(bool no_dead_code) {
  3219   if (VerifyGraphEdges) {
  3220     ResourceArea *area = Thread::current()->resource_area();
  3221     Unique_Node_List visited(area);
  3222     // Call recursive graph walk to check edges
  3223     _root->verify_edges(visited);
  3224     if (no_dead_code) {
  3225       // Now make sure that no visited node is used by an unvisited node.
  3226       bool dead_nodes = 0;
  3227       Unique_Node_List checked(area);
  3228       while (visited.size() > 0) {
  3229         Node* n = visited.pop();
  3230         checked.push(n);
  3231         for (uint i = 0; i < n->outcnt(); i++) {
  3232           Node* use = n->raw_out(i);
  3233           if (checked.member(use))  continue;  // already checked
  3234           if (visited.member(use))  continue;  // already in the graph
  3235           if (use->is_Con())        continue;  // a dead ConNode is OK
  3236           // At this point, we have found a dead node which is DU-reachable.
  3237           if (dead_nodes++ == 0)
  3238             tty->print_cr("*** Dead nodes reachable via DU edges:");
  3239           use->dump(2);
  3240           tty->print_cr("---");
  3241           checked.push(use);  // No repeats; pretend it is now checked.
  3244       assert(dead_nodes == 0, "using nodes must be reachable from root");
  3248 #endif
  3250 // The Compile object keeps track of failure reasons separately from the ciEnv.
  3251 // This is required because there is not quite a 1-1 relation between the
  3252 // ciEnv and its compilation task and the Compile object.  Note that one
  3253 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
  3254 // to backtrack and retry without subsuming loads.  Other than this backtracking
  3255 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
  3256 // by the logic in C2Compiler.
  3257 void Compile::record_failure(const char* reason) {
  3258   if (log() != NULL) {
  3259     log()->elem("failure reason='%s' phase='compile'", reason);
  3261   if (_failure_reason == NULL) {
  3262     // Record the first failure reason.
  3263     _failure_reason = reason;
  3265   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
  3266     C->print_method(_failure_reason);
  3268   _root = NULL;  // flush the graph, too
  3271 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator, bool dolog)
  3272   : TraceTime(NULL, accumulator, false NOT_PRODUCT( || TimeCompiler ), false),
  3273     _phase_name(name), _dolog(dolog)
  3275   if (dolog) {
  3276     C = Compile::current();
  3277     _log = C->log();
  3278   } else {
  3279     C = NULL;
  3280     _log = NULL;
  3282   if (_log != NULL) {
  3283     _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
  3284     _log->stamp();
  3285     _log->end_head();
  3289 Compile::TracePhase::~TracePhase() {
  3291   C = Compile::current();
  3292   if (_dolog) {
  3293     _log = C->log();
  3294   } else {
  3295     _log = NULL;
  3298 #ifdef ASSERT
  3299   if (PrintIdealNodeCount) {
  3300     tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
  3301                   _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
  3304   if (VerifyIdealNodeCount) {
  3305     Compile::current()->print_missing_nodes();
  3307 #endif
  3309   if (_log != NULL) {
  3310     _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
  3314 //=============================================================================
  3315 // Two Constant's are equal when the type and the value are equal.
  3316 bool Compile::Constant::operator==(const Constant& other) {
  3317   if (type()          != other.type()         )  return false;
  3318   if (can_be_reused() != other.can_be_reused())  return false;
  3319   // For floating point values we compare the bit pattern.
  3320   switch (type()) {
  3321   case T_FLOAT:   return (_v._value.i == other._v._value.i);
  3322   case T_LONG:
  3323   case T_DOUBLE:  return (_v._value.j == other._v._value.j);
  3324   case T_OBJECT:
  3325   case T_ADDRESS: return (_v._value.l == other._v._value.l);
  3326   case T_VOID:    return (_v._value.l == other._v._value.l);  // jump-table entries
  3327   case T_METADATA: return (_v._metadata == other._v._metadata);
  3328   default: ShouldNotReachHere();
  3330   return false;
  3333 static int type_to_size_in_bytes(BasicType t) {
  3334   switch (t) {
  3335   case T_LONG:    return sizeof(jlong  );
  3336   case T_FLOAT:   return sizeof(jfloat );
  3337   case T_DOUBLE:  return sizeof(jdouble);
  3338   case T_METADATA: return sizeof(Metadata*);
  3339     // We use T_VOID as marker for jump-table entries (labels) which
  3340     // need an internal word relocation.
  3341   case T_VOID:
  3342   case T_ADDRESS:
  3343   case T_OBJECT:  return sizeof(jobject);
  3346   ShouldNotReachHere();
  3347   return -1;
  3350 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
  3351   // sort descending
  3352   if (a->freq() > b->freq())  return -1;
  3353   if (a->freq() < b->freq())  return  1;
  3354   return 0;
  3357 void Compile::ConstantTable::calculate_offsets_and_size() {
  3358   // First, sort the array by frequencies.
  3359   _constants.sort(qsort_comparator);
  3361 #ifdef ASSERT
  3362   // Make sure all jump-table entries were sorted to the end of the
  3363   // array (they have a negative frequency).
  3364   bool found_void = false;
  3365   for (int i = 0; i < _constants.length(); i++) {
  3366     Constant con = _constants.at(i);
  3367     if (con.type() == T_VOID)
  3368       found_void = true;  // jump-tables
  3369     else
  3370       assert(!found_void, "wrong sorting");
  3372 #endif
  3374   int offset = 0;
  3375   for (int i = 0; i < _constants.length(); i++) {
  3376     Constant* con = _constants.adr_at(i);
  3378     // Align offset for type.
  3379     int typesize = type_to_size_in_bytes(con->type());
  3380     offset = align_size_up(offset, typesize);
  3381     con->set_offset(offset);   // set constant's offset
  3383     if (con->type() == T_VOID) {
  3384       MachConstantNode* n = (MachConstantNode*) con->get_jobject();
  3385       offset = offset + typesize * n->outcnt();  // expand jump-table
  3386     } else {
  3387       offset = offset + typesize;
  3391   // Align size up to the next section start (which is insts; see
  3392   // CodeBuffer::align_at_start).
  3393   assert(_size == -1, "already set?");
  3394   _size = align_size_up(offset, CodeEntryAlignment);
  3397 void Compile::ConstantTable::emit(CodeBuffer& cb) {
  3398   MacroAssembler _masm(&cb);
  3399   for (int i = 0; i < _constants.length(); i++) {
  3400     Constant con = _constants.at(i);
  3401     address constant_addr;
  3402     switch (con.type()) {
  3403     case T_LONG:   constant_addr = _masm.long_constant(  con.get_jlong()  ); break;
  3404     case T_FLOAT:  constant_addr = _masm.float_constant( con.get_jfloat() ); break;
  3405     case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
  3406     case T_OBJECT: {
  3407       jobject obj = con.get_jobject();
  3408       int oop_index = _masm.oop_recorder()->find_index(obj);
  3409       constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
  3410       break;
  3412     case T_ADDRESS: {
  3413       address addr = (address) con.get_jobject();
  3414       constant_addr = _masm.address_constant(addr);
  3415       break;
  3417     // We use T_VOID as marker for jump-table entries (labels) which
  3418     // need an internal word relocation.
  3419     case T_VOID: {
  3420       MachConstantNode* n = (MachConstantNode*) con.get_jobject();
  3421       // Fill the jump-table with a dummy word.  The real value is
  3422       // filled in later in fill_jump_table.
  3423       address dummy = (address) n;
  3424       constant_addr = _masm.address_constant(dummy);
  3425       // Expand jump-table
  3426       for (uint i = 1; i < n->outcnt(); i++) {
  3427         address temp_addr = _masm.address_constant(dummy + i);
  3428         assert(temp_addr, "consts section too small");
  3430       break;
  3432     case T_METADATA: {
  3433       Metadata* obj = con.get_metadata();
  3434       int metadata_index = _masm.oop_recorder()->find_index(obj);
  3435       constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
  3436       break;
  3438     default: ShouldNotReachHere();
  3440     assert(constant_addr, "consts section too small");
  3441     assert((constant_addr - _masm.code()->consts()->start()) == con.offset(), err_msg_res("must be: %d == %d", constant_addr - _masm.code()->consts()->start(), con.offset()));
  3445 int Compile::ConstantTable::find_offset(Constant& con) const {
  3446   int idx = _constants.find(con);
  3447   assert(idx != -1, "constant must be in constant table");
  3448   int offset = _constants.at(idx).offset();
  3449   assert(offset != -1, "constant table not emitted yet?");
  3450   return offset;
  3453 void Compile::ConstantTable::add(Constant& con) {
  3454   if (con.can_be_reused()) {
  3455     int idx = _constants.find(con);
  3456     if (idx != -1 && _constants.at(idx).can_be_reused()) {
  3457       _constants.adr_at(idx)->inc_freq(con.freq());  // increase the frequency by the current value
  3458       return;
  3461   (void) _constants.append(con);
  3464 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
  3465   Block* b = Compile::current()->cfg()->_bbs[n->_idx];
  3466   Constant con(type, value, b->_freq);
  3467   add(con);
  3468   return con;
  3471 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
  3472   Constant con(metadata);
  3473   add(con);
  3474   return con;
  3477 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
  3478   jvalue value;
  3479   BasicType type = oper->type()->basic_type();
  3480   switch (type) {
  3481   case T_LONG:    value.j = oper->constantL(); break;
  3482   case T_FLOAT:   value.f = oper->constantF(); break;
  3483   case T_DOUBLE:  value.d = oper->constantD(); break;
  3484   case T_OBJECT:
  3485   case T_ADDRESS: value.l = (jobject) oper->constant(); break;
  3486   case T_METADATA: return add((Metadata*)oper->constant()); break;
  3487   default: guarantee(false, err_msg_res("unhandled type: %s", type2name(type)));
  3489   return add(n, type, value);
  3492 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
  3493   jvalue value;
  3494   // We can use the node pointer here to identify the right jump-table
  3495   // as this method is called from Compile::Fill_buffer right before
  3496   // the MachNodes are emitted and the jump-table is filled (means the
  3497   // MachNode pointers do not change anymore).
  3498   value.l = (jobject) n;
  3499   Constant con(T_VOID, value, next_jump_table_freq(), false);  // Labels of a jump-table cannot be reused.
  3500   add(con);
  3501   return con;
  3504 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
  3505   // If called from Compile::scratch_emit_size do nothing.
  3506   if (Compile::current()->in_scratch_emit_size())  return;
  3508   assert(labels.is_nonempty(), "must be");
  3509   assert((uint) labels.length() == n->outcnt(), err_msg_res("must be equal: %d == %d", labels.length(), n->outcnt()));
  3511   // Since MachConstantNode::constant_offset() also contains
  3512   // table_base_offset() we need to subtract the table_base_offset()
  3513   // to get the plain offset into the constant table.
  3514   int offset = n->constant_offset() - table_base_offset();
  3516   MacroAssembler _masm(&cb);
  3517   address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
  3519   for (uint i = 0; i < n->outcnt(); i++) {
  3520     address* constant_addr = &jump_table_base[i];
  3521     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)));
  3522     *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
  3523     cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
  3527 void Compile::dump_inlining() {
  3528   if (PrintInlining || PrintIntrinsics NOT_PRODUCT( || PrintOptoInlining)) {
  3529     // Print inlining message for candidates that we couldn't inline
  3530     // for lack of space or non constant receiver
  3531     for (int i = 0; i < _late_inlines.length(); i++) {
  3532       CallGenerator* cg = _late_inlines.at(i);
  3533       cg->print_inlining_late("live nodes > LiveNodeCountInliningCutoff");
  3535     Unique_Node_List useful;
  3536     useful.push(root());
  3537     for (uint next = 0; next < useful.size(); ++next) {
  3538       Node* n  = useful.at(next);
  3539       if (n->is_Call() && n->as_Call()->generator() != NULL && n->as_Call()->generator()->call_node() == n) {
  3540         CallNode* call = n->as_Call();
  3541         CallGenerator* cg = call->generator();
  3542         cg->print_inlining_late("receiver not constant");
  3544       uint max = n->len();
  3545       for ( uint i = 0; i < max; ++i ) {
  3546         Node *m = n->in(i);
  3547         if ( m == NULL ) continue;
  3548         useful.push(m);
  3551     for (int i = 0; i < _print_inlining_list->length(); i++) {
  3552       tty->print(_print_inlining_list->at(i).ss()->as_string());
  3557 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
  3558   if (n1->Opcode() < n2->Opcode())      return -1;
  3559   else if (n1->Opcode() > n2->Opcode()) return 1;
  3561   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()));
  3562   for (uint i = 1; i < n1->req(); i++) {
  3563     if (n1->in(i) < n2->in(i))      return -1;
  3564     else if (n1->in(i) > n2->in(i)) return 1;
  3567   return 0;
  3570 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
  3571   Node* n1 = *n1p;
  3572   Node* n2 = *n2p;
  3574   return cmp_expensive_nodes(n1, n2);
  3577 void Compile::sort_expensive_nodes() {
  3578   if (!expensive_nodes_sorted()) {
  3579     _expensive_nodes->sort(cmp_expensive_nodes);
  3583 bool Compile::expensive_nodes_sorted() const {
  3584   for (int i = 1; i < _expensive_nodes->length(); i++) {
  3585     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
  3586       return false;
  3589   return true;
  3592 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
  3593   if (_expensive_nodes->length() == 0) {
  3594     return false;
  3597   assert(OptimizeExpensiveOps, "optimization off?");
  3599   // Take this opportunity to remove dead nodes from the list
  3600   int j = 0;
  3601   for (int i = 0; i < _expensive_nodes->length(); i++) {
  3602     Node* n = _expensive_nodes->at(i);
  3603     if (!n->is_unreachable(igvn)) {
  3604       assert(n->is_expensive(), "should be expensive");
  3605       _expensive_nodes->at_put(j, n);
  3606       j++;
  3609   _expensive_nodes->trunc_to(j);
  3611   // Then sort the list so that similar nodes are next to each other
  3612   // and check for at least two nodes of identical kind with same data
  3613   // inputs.
  3614   sort_expensive_nodes();
  3616   for (int i = 0; i < _expensive_nodes->length()-1; i++) {
  3617     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
  3618       return true;
  3622   return false;
  3625 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
  3626   if (_expensive_nodes->length() == 0) {
  3627     return;
  3630   assert(OptimizeExpensiveOps, "optimization off?");
  3632   // Sort to bring similar nodes next to each other and clear the
  3633   // control input of nodes for which there's only a single copy.
  3634   sort_expensive_nodes();
  3636   int j = 0;
  3637   int identical = 0;
  3638   int i = 0;
  3639   for (; i < _expensive_nodes->length()-1; i++) {
  3640     assert(j <= i, "can't write beyond current index");
  3641     if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
  3642       identical++;
  3643       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3644       continue;
  3646     if (identical > 0) {
  3647       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3648       identical = 0;
  3649     } else {
  3650       Node* n = _expensive_nodes->at(i);
  3651       igvn.hash_delete(n);
  3652       n->set_req(0, NULL);
  3653       igvn.hash_insert(n);
  3656   if (identical > 0) {
  3657     _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3658   } else if (_expensive_nodes->length() >= 1) {
  3659     Node* n = _expensive_nodes->at(i);
  3660     igvn.hash_delete(n);
  3661     n->set_req(0, NULL);
  3662     igvn.hash_insert(n);
  3664   _expensive_nodes->trunc_to(j);
  3667 void Compile::add_expensive_node(Node * n) {
  3668   assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
  3669   assert(n->is_expensive(), "expensive nodes with non-null control here only");
  3670   assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
  3671   if (OptimizeExpensiveOps) {
  3672     _expensive_nodes->append(n);
  3673   } else {
  3674     // Clear control input and let IGVN optimize expensive nodes if
  3675     // OptimizeExpensiveOps is off.
  3676     n->set_req(0, NULL);
  3680 // Auxiliary method to support randomized stressing/fuzzing.
  3681 //
  3682 // This method can be called the arbitrary number of times, with current count
  3683 // as the argument. The logic allows selecting a single candidate from the
  3684 // running list of candidates as follows:
  3685 //    int count = 0;
  3686 //    Cand* selected = null;
  3687 //    while(cand = cand->next()) {
  3688 //      if (randomized_select(++count)) {
  3689 //        selected = cand;
  3690 //      }
  3691 //    }
  3692 //
  3693 // Including count equalizes the chances any candidate is "selected".
  3694 // This is useful when we don't have the complete list of candidates to choose
  3695 // from uniformly. In this case, we need to adjust the randomicity of the
  3696 // selection, or else we will end up biasing the selection towards the latter
  3697 // candidates.
  3698 //
  3699 // Quick back-envelope calculation shows that for the list of n candidates
  3700 // the equal probability for the candidate to persist as "best" can be
  3701 // achieved by replacing it with "next" k-th candidate with the probability
  3702 // of 1/k. It can be easily shown that by the end of the run, the
  3703 // probability for any candidate is converged to 1/n, thus giving the
  3704 // uniform distribution among all the candidates.
  3705 //
  3706 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
  3707 #define RANDOMIZED_DOMAIN_POW 29
  3708 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
  3709 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
  3710 bool Compile::randomized_select(int count) {
  3711   assert(count > 0, "only positive");
  3712   return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);

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