src/share/vm/opto/compile.cpp

Thu, 20 Feb 2014 11:05:12 +0100

author
goetz
date
Thu, 20 Feb 2014 11:05:12 +0100
changeset 6510
7c462558a08a
parent 6507
752ba2e5f6d0
child 6518
62c54fcc0a35
permissions
-rw-r--r--

8035394: PPC64: Make usage of intrinsic dsqrt depend on processor recognition.
Reviewed-by: kvn

     1 /*
     2  * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.
     8  *
     9  * This code is distributed in the hope that it will be useful, but WITHOUT
    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    12  * version 2 for more details (a copy is included in the LICENSE file that
    13  * accompanied this code).
    14  *
    15  * You should have received a copy of the GNU General Public License version
    16  * 2 along with this work; if not, write to the Free Software Foundation,
    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    18  *
    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    20  * or visit www.oracle.com if you need additional information or have any
    21  * questions.
    22  *
    23  */
    25 #include "precompiled.hpp"
    26 #include "asm/macroAssembler.hpp"
    27 #include "asm/macroAssembler.inline.hpp"
    28 #include "ci/ciReplay.hpp"
    29 #include "classfile/systemDictionary.hpp"
    30 #include "code/exceptionHandlerTable.hpp"
    31 #include "code/nmethod.hpp"
    32 #include "compiler/compileLog.hpp"
    33 #include "compiler/disassembler.hpp"
    34 #include "compiler/oopMap.hpp"
    35 #include "opto/addnode.hpp"
    36 #include "opto/block.hpp"
    37 #include "opto/c2compiler.hpp"
    38 #include "opto/callGenerator.hpp"
    39 #include "opto/callnode.hpp"
    40 #include "opto/cfgnode.hpp"
    41 #include "opto/chaitin.hpp"
    42 #include "opto/compile.hpp"
    43 #include "opto/connode.hpp"
    44 #include "opto/divnode.hpp"
    45 #include "opto/escape.hpp"
    46 #include "opto/idealGraphPrinter.hpp"
    47 #include "opto/loopnode.hpp"
    48 #include "opto/machnode.hpp"
    49 #include "opto/macro.hpp"
    50 #include "opto/matcher.hpp"
    51 #include "opto/mathexactnode.hpp"
    52 #include "opto/memnode.hpp"
    53 #include "opto/mulnode.hpp"
    54 #include "opto/node.hpp"
    55 #include "opto/opcodes.hpp"
    56 #include "opto/output.hpp"
    57 #include "opto/parse.hpp"
    58 #include "opto/phaseX.hpp"
    59 #include "opto/rootnode.hpp"
    60 #include "opto/runtime.hpp"
    61 #include "opto/stringopts.hpp"
    62 #include "opto/type.hpp"
    63 #include "opto/vectornode.hpp"
    64 #include "runtime/arguments.hpp"
    65 #include "runtime/signature.hpp"
    66 #include "runtime/stubRoutines.hpp"
    67 #include "runtime/timer.hpp"
    68 #include "trace/tracing.hpp"
    69 #include "utilities/copy.hpp"
    70 #ifdef TARGET_ARCH_MODEL_x86_32
    71 # include "adfiles/ad_x86_32.hpp"
    72 #endif
    73 #ifdef TARGET_ARCH_MODEL_x86_64
    74 # include "adfiles/ad_x86_64.hpp"
    75 #endif
    76 #ifdef TARGET_ARCH_MODEL_sparc
    77 # include "adfiles/ad_sparc.hpp"
    78 #endif
    79 #ifdef TARGET_ARCH_MODEL_zero
    80 # include "adfiles/ad_zero.hpp"
    81 #endif
    82 #ifdef TARGET_ARCH_MODEL_arm
    83 # include "adfiles/ad_arm.hpp"
    84 #endif
    85 #ifdef TARGET_ARCH_MODEL_ppc_32
    86 # include "adfiles/ad_ppc_32.hpp"
    87 #endif
    88 #ifdef TARGET_ARCH_MODEL_ppc_64
    89 # include "adfiles/ad_ppc_64.hpp"
    90 #endif
    93 // -------------------- Compile::mach_constant_base_node -----------------------
    94 // Constant table base node singleton.
    95 MachConstantBaseNode* Compile::mach_constant_base_node() {
    96   if (_mach_constant_base_node == NULL) {
    97     _mach_constant_base_node = new (C) MachConstantBaseNode();
    98     _mach_constant_base_node->add_req(C->root());
    99   }
   100   return _mach_constant_base_node;
   101 }
   104 /// Support for intrinsics.
   106 // Return the index at which m must be inserted (or already exists).
   107 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
   108 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual) {
   109 #ifdef ASSERT
   110   for (int i = 1; i < _intrinsics->length(); i++) {
   111     CallGenerator* cg1 = _intrinsics->at(i-1);
   112     CallGenerator* cg2 = _intrinsics->at(i);
   113     assert(cg1->method() != cg2->method()
   114            ? cg1->method()     < cg2->method()
   115            : cg1->is_virtual() < cg2->is_virtual(),
   116            "compiler intrinsics list must stay sorted");
   117   }
   118 #endif
   119   // Binary search sorted list, in decreasing intervals [lo, hi].
   120   int lo = 0, hi = _intrinsics->length()-1;
   121   while (lo <= hi) {
   122     int mid = (uint)(hi + lo) / 2;
   123     ciMethod* mid_m = _intrinsics->at(mid)->method();
   124     if (m < mid_m) {
   125       hi = mid-1;
   126     } else if (m > mid_m) {
   127       lo = mid+1;
   128     } else {
   129       // look at minor sort key
   130       bool mid_virt = _intrinsics->at(mid)->is_virtual();
   131       if (is_virtual < mid_virt) {
   132         hi = mid-1;
   133       } else if (is_virtual > mid_virt) {
   134         lo = mid+1;
   135       } else {
   136         return mid;  // exact match
   137       }
   138     }
   139   }
   140   return lo;  // inexact match
   141 }
   143 void Compile::register_intrinsic(CallGenerator* cg) {
   144   if (_intrinsics == NULL) {
   145     _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
   146   }
   147   // This code is stolen from ciObjectFactory::insert.
   148   // Really, GrowableArray should have methods for
   149   // insert_at, remove_at, and binary_search.
   150   int len = _intrinsics->length();
   151   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual());
   152   if (index == len) {
   153     _intrinsics->append(cg);
   154   } else {
   155 #ifdef ASSERT
   156     CallGenerator* oldcg = _intrinsics->at(index);
   157     assert(oldcg->method() != cg->method() || oldcg->is_virtual() != cg->is_virtual(), "don't register twice");
   158 #endif
   159     _intrinsics->append(_intrinsics->at(len-1));
   160     int pos;
   161     for (pos = len-2; pos >= index; pos--) {
   162       _intrinsics->at_put(pos+1,_intrinsics->at(pos));
   163     }
   164     _intrinsics->at_put(index, cg);
   165   }
   166   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
   167 }
   169 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
   170   assert(m->is_loaded(), "don't try this on unloaded methods");
   171   if (_intrinsics != NULL) {
   172     int index = intrinsic_insertion_index(m, is_virtual);
   173     if (index < _intrinsics->length()
   174         && _intrinsics->at(index)->method() == m
   175         && _intrinsics->at(index)->is_virtual() == is_virtual) {
   176       return _intrinsics->at(index);
   177     }
   178   }
   179   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
   180   if (m->intrinsic_id() != vmIntrinsics::_none &&
   181       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
   182     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
   183     if (cg != NULL) {
   184       // Save it for next time:
   185       register_intrinsic(cg);
   186       return cg;
   187     } else {
   188       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
   189     }
   190   }
   191   return NULL;
   192 }
   194 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
   195 // in library_call.cpp.
   198 #ifndef PRODUCT
   199 // statistics gathering...
   201 juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
   202 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
   204 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
   205   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
   206   int oflags = _intrinsic_hist_flags[id];
   207   assert(flags != 0, "what happened?");
   208   if (is_virtual) {
   209     flags |= _intrinsic_virtual;
   210   }
   211   bool changed = (flags != oflags);
   212   if ((flags & _intrinsic_worked) != 0) {
   213     juint count = (_intrinsic_hist_count[id] += 1);
   214     if (count == 1) {
   215       changed = true;           // first time
   216     }
   217     // increment the overall count also:
   218     _intrinsic_hist_count[vmIntrinsics::_none] += 1;
   219   }
   220   if (changed) {
   221     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
   222       // Something changed about the intrinsic's virtuality.
   223       if ((flags & _intrinsic_virtual) != 0) {
   224         // This is the first use of this intrinsic as a virtual call.
   225         if (oflags != 0) {
   226           // We already saw it as a non-virtual, so note both cases.
   227           flags |= _intrinsic_both;
   228         }
   229       } else if ((oflags & _intrinsic_both) == 0) {
   230         // This is the first use of this intrinsic as a non-virtual
   231         flags |= _intrinsic_both;
   232       }
   233     }
   234     _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
   235   }
   236   // update the overall flags also:
   237   _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
   238   return changed;
   239 }
   241 static char* format_flags(int flags, char* buf) {
   242   buf[0] = 0;
   243   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
   244   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
   245   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
   246   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
   247   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
   248   if (buf[0] == 0)  strcat(buf, ",");
   249   assert(buf[0] == ',', "must be");
   250   return &buf[1];
   251 }
   253 void Compile::print_intrinsic_statistics() {
   254   char flagsbuf[100];
   255   ttyLocker ttyl;
   256   if (xtty != NULL)  xtty->head("statistics type='intrinsic'");
   257   tty->print_cr("Compiler intrinsic usage:");
   258   juint total = _intrinsic_hist_count[vmIntrinsics::_none];
   259   if (total == 0)  total = 1;  // avoid div0 in case of no successes
   260   #define PRINT_STAT_LINE(name, c, f) \
   261     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
   262   for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
   263     vmIntrinsics::ID id = (vmIntrinsics::ID) index;
   264     int   flags = _intrinsic_hist_flags[id];
   265     juint count = _intrinsic_hist_count[id];
   266     if ((flags | count) != 0) {
   267       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
   268     }
   269   }
   270   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
   271   if (xtty != NULL)  xtty->tail("statistics");
   272 }
   274 void Compile::print_statistics() {
   275   { ttyLocker ttyl;
   276     if (xtty != NULL)  xtty->head("statistics type='opto'");
   277     Parse::print_statistics();
   278     PhaseCCP::print_statistics();
   279     PhaseRegAlloc::print_statistics();
   280     Scheduling::print_statistics();
   281     PhasePeephole::print_statistics();
   282     PhaseIdealLoop::print_statistics();
   283     if (xtty != NULL)  xtty->tail("statistics");
   284   }
   285   if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
   286     // put this under its own <statistics> element.
   287     print_intrinsic_statistics();
   288   }
   289 }
   290 #endif //PRODUCT
   292 // Support for bundling info
   293 Bundle* Compile::node_bundling(const Node *n) {
   294   assert(valid_bundle_info(n), "oob");
   295   return &_node_bundling_base[n->_idx];
   296 }
   298 bool Compile::valid_bundle_info(const Node *n) {
   299   return (_node_bundling_limit > n->_idx);
   300 }
   303 void Compile::gvn_replace_by(Node* n, Node* nn) {
   304   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
   305     Node* use = n->last_out(i);
   306     bool is_in_table = initial_gvn()->hash_delete(use);
   307     uint uses_found = 0;
   308     for (uint j = 0; j < use->len(); j++) {
   309       if (use->in(j) == n) {
   310         if (j < use->req())
   311           use->set_req(j, nn);
   312         else
   313           use->set_prec(j, nn);
   314         uses_found++;
   315       }
   316     }
   317     if (is_in_table) {
   318       // reinsert into table
   319       initial_gvn()->hash_find_insert(use);
   320     }
   321     record_for_igvn(use);
   322     i -= uses_found;    // we deleted 1 or more copies of this edge
   323   }
   324 }
   327 static inline bool not_a_node(const Node* n) {
   328   if (n == NULL)                   return true;
   329   if (((intptr_t)n & 1) != 0)      return true;  // uninitialized, etc.
   330   if (*(address*)n == badAddress)  return true;  // kill by Node::destruct
   331   return false;
   332 }
   334 // Identify all nodes that are reachable from below, useful.
   335 // Use breadth-first pass that records state in a Unique_Node_List,
   336 // recursive traversal is slower.
   337 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
   338   int estimated_worklist_size = unique();
   339   useful.map( estimated_worklist_size, NULL );  // preallocate space
   341   // Initialize worklist
   342   if (root() != NULL)     { useful.push(root()); }
   343   // If 'top' is cached, declare it useful to preserve cached node
   344   if( cached_top_node() ) { useful.push(cached_top_node()); }
   346   // Push all useful nodes onto the list, breadthfirst
   347   for( uint next = 0; next < useful.size(); ++next ) {
   348     assert( next < unique(), "Unique useful nodes < total nodes");
   349     Node *n  = useful.at(next);
   350     uint max = n->len();
   351     for( uint i = 0; i < max; ++i ) {
   352       Node *m = n->in(i);
   353       if (not_a_node(m))  continue;
   354       useful.push(m);
   355     }
   356   }
   357 }
   359 // Update dead_node_list with any missing dead nodes using useful
   360 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
   361 void Compile::update_dead_node_list(Unique_Node_List &useful) {
   362   uint max_idx = unique();
   363   VectorSet& useful_node_set = useful.member_set();
   365   for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
   366     // If node with index node_idx is not in useful set,
   367     // mark it as dead in dead node list.
   368     if (! useful_node_set.test(node_idx) ) {
   369       record_dead_node(node_idx);
   370     }
   371   }
   372 }
   374 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
   375   int shift = 0;
   376   for (int i = 0; i < inlines->length(); i++) {
   377     CallGenerator* cg = inlines->at(i);
   378     CallNode* call = cg->call_node();
   379     if (shift > 0) {
   380       inlines->at_put(i-shift, cg);
   381     }
   382     if (!useful.member(call)) {
   383       shift++;
   384     }
   385   }
   386   inlines->trunc_to(inlines->length()-shift);
   387 }
   389 // Disconnect all useless nodes by disconnecting those at the boundary.
   390 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
   391   uint next = 0;
   392   while (next < useful.size()) {
   393     Node *n = useful.at(next++);
   394     // Use raw traversal of out edges since this code removes out edges
   395     int max = n->outcnt();
   396     for (int j = 0; j < max; ++j) {
   397       Node* child = n->raw_out(j);
   398       if (! useful.member(child)) {
   399         assert(!child->is_top() || child != top(),
   400                "If top is cached in Compile object it is in useful list");
   401         // Only need to remove this out-edge to the useless node
   402         n->raw_del_out(j);
   403         --j;
   404         --max;
   405       }
   406     }
   407     if (n->outcnt() == 1 && n->has_special_unique_user()) {
   408       record_for_igvn(n->unique_out());
   409     }
   410   }
   411   // Remove useless macro and predicate opaq nodes
   412   for (int i = C->macro_count()-1; i >= 0; i--) {
   413     Node* n = C->macro_node(i);
   414     if (!useful.member(n)) {
   415       remove_macro_node(n);
   416     }
   417   }
   418   // Remove useless expensive node
   419   for (int i = C->expensive_count()-1; i >= 0; i--) {
   420     Node* n = C->expensive_node(i);
   421     if (!useful.member(n)) {
   422       remove_expensive_node(n);
   423     }
   424   }
   425   // clean up the late inline lists
   426   remove_useless_late_inlines(&_string_late_inlines, useful);
   427   remove_useless_late_inlines(&_boxing_late_inlines, useful);
   428   remove_useless_late_inlines(&_late_inlines, useful);
   429   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
   430 }
   432 //------------------------------frame_size_in_words-----------------------------
   433 // frame_slots in units of words
   434 int Compile::frame_size_in_words() const {
   435   // shift is 0 in LP32 and 1 in LP64
   436   const int shift = (LogBytesPerWord - LogBytesPerInt);
   437   int words = _frame_slots >> shift;
   438   assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
   439   return words;
   440 }
   442 // ============================================================================
   443 //------------------------------CompileWrapper---------------------------------
   444 class CompileWrapper : public StackObj {
   445   Compile *const _compile;
   446  public:
   447   CompileWrapper(Compile* compile);
   449   ~CompileWrapper();
   450 };
   452 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
   453   // the Compile* pointer is stored in the current ciEnv:
   454   ciEnv* env = compile->env();
   455   assert(env == ciEnv::current(), "must already be a ciEnv active");
   456   assert(env->compiler_data() == NULL, "compile already active?");
   457   env->set_compiler_data(compile);
   458   assert(compile == Compile::current(), "sanity");
   460   compile->set_type_dict(NULL);
   461   compile->set_type_hwm(NULL);
   462   compile->set_type_last_size(0);
   463   compile->set_last_tf(NULL, NULL);
   464   compile->set_indexSet_arena(NULL);
   465   compile->set_indexSet_free_block_list(NULL);
   466   compile->init_type_arena();
   467   Type::Initialize(compile);
   468   _compile->set_scratch_buffer_blob(NULL);
   469   _compile->begin_method();
   470 }
   471 CompileWrapper::~CompileWrapper() {
   472   _compile->end_method();
   473   if (_compile->scratch_buffer_blob() != NULL)
   474     BufferBlob::free(_compile->scratch_buffer_blob());
   475   _compile->env()->set_compiler_data(NULL);
   476 }
   479 //----------------------------print_compile_messages---------------------------
   480 void Compile::print_compile_messages() {
   481 #ifndef PRODUCT
   482   // Check if recompiling
   483   if (_subsume_loads == false && PrintOpto) {
   484     // Recompiling without allowing machine instructions to subsume loads
   485     tty->print_cr("*********************************************************");
   486     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
   487     tty->print_cr("*********************************************************");
   488   }
   489   if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
   490     // Recompiling without escape analysis
   491     tty->print_cr("*********************************************************");
   492     tty->print_cr("** Bailout: Recompile without escape analysis          **");
   493     tty->print_cr("*********************************************************");
   494   }
   495   if (_eliminate_boxing != EliminateAutoBox && PrintOpto) {
   496     // Recompiling without boxing elimination
   497     tty->print_cr("*********************************************************");
   498     tty->print_cr("** Bailout: Recompile without boxing elimination       **");
   499     tty->print_cr("*********************************************************");
   500   }
   501   if (env()->break_at_compile()) {
   502     // Open the debugger when compiling this method.
   503     tty->print("### Breaking when compiling: ");
   504     method()->print_short_name();
   505     tty->cr();
   506     BREAKPOINT;
   507   }
   509   if( PrintOpto ) {
   510     if (is_osr_compilation()) {
   511       tty->print("[OSR]%3d", _compile_id);
   512     } else {
   513       tty->print("%3d", _compile_id);
   514     }
   515   }
   516 #endif
   517 }
   520 //-----------------------init_scratch_buffer_blob------------------------------
   521 // Construct a temporary BufferBlob and cache it for this compile.
   522 void Compile::init_scratch_buffer_blob(int const_size) {
   523   // If there is already a scratch buffer blob allocated and the
   524   // constant section is big enough, use it.  Otherwise free the
   525   // current and allocate a new one.
   526   BufferBlob* blob = scratch_buffer_blob();
   527   if ((blob != NULL) && (const_size <= _scratch_const_size)) {
   528     // Use the current blob.
   529   } else {
   530     if (blob != NULL) {
   531       BufferBlob::free(blob);
   532     }
   534     ResourceMark rm;
   535     _scratch_const_size = const_size;
   536     int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
   537     blob = BufferBlob::create("Compile::scratch_buffer", size);
   538     // Record the buffer blob for next time.
   539     set_scratch_buffer_blob(blob);
   540     // Have we run out of code space?
   541     if (scratch_buffer_blob() == NULL) {
   542       // Let CompilerBroker disable further compilations.
   543       record_failure("Not enough space for scratch buffer in CodeCache");
   544       return;
   545     }
   546   }
   548   // Initialize the relocation buffers
   549   relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
   550   set_scratch_locs_memory(locs_buf);
   551 }
   554 //-----------------------scratch_emit_size-------------------------------------
   555 // Helper function that computes size by emitting code
   556 uint Compile::scratch_emit_size(const Node* n) {
   557   // Start scratch_emit_size section.
   558   set_in_scratch_emit_size(true);
   560   // Emit into a trash buffer and count bytes emitted.
   561   // This is a pretty expensive way to compute a size,
   562   // but it works well enough if seldom used.
   563   // All common fixed-size instructions are given a size
   564   // method by the AD file.
   565   // Note that the scratch buffer blob and locs memory are
   566   // allocated at the beginning of the compile task, and
   567   // may be shared by several calls to scratch_emit_size.
   568   // The allocation of the scratch buffer blob is particularly
   569   // expensive, since it has to grab the code cache lock.
   570   BufferBlob* blob = this->scratch_buffer_blob();
   571   assert(blob != NULL, "Initialize BufferBlob at start");
   572   assert(blob->size() > MAX_inst_size, "sanity");
   573   relocInfo* locs_buf = scratch_locs_memory();
   574   address blob_begin = blob->content_begin();
   575   address blob_end   = (address)locs_buf;
   576   assert(blob->content_contains(blob_end), "sanity");
   577   CodeBuffer buf(blob_begin, blob_end - blob_begin);
   578   buf.initialize_consts_size(_scratch_const_size);
   579   buf.initialize_stubs_size(MAX_stubs_size);
   580   assert(locs_buf != NULL, "sanity");
   581   int lsize = MAX_locs_size / 3;
   582   buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
   583   buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
   584   buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
   586   // Do the emission.
   588   Label fakeL; // Fake label for branch instructions.
   589   Label*   saveL = NULL;
   590   uint save_bnum = 0;
   591   bool is_branch = n->is_MachBranch();
   592   if (is_branch) {
   593     MacroAssembler masm(&buf);
   594     masm.bind(fakeL);
   595     n->as_MachBranch()->save_label(&saveL, &save_bnum);
   596     n->as_MachBranch()->label_set(&fakeL, 0);
   597   }
   598   n->emit(buf, this->regalloc());
   599   if (is_branch) // Restore label.
   600     n->as_MachBranch()->label_set(saveL, save_bnum);
   602   // End scratch_emit_size section.
   603   set_in_scratch_emit_size(false);
   605   return buf.insts_size();
   606 }
   609 // ============================================================================
   610 //------------------------------Compile standard-------------------------------
   611 debug_only( int Compile::_debug_idx = 100000; )
   613 // Compile a method.  entry_bci is -1 for normal compilations and indicates
   614 // the continuation bci for on stack replacement.
   617 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci,
   618                   bool subsume_loads, bool do_escape_analysis, bool eliminate_boxing )
   619                 : Phase(Compiler),
   620                   _env(ci_env),
   621                   _log(ci_env->log()),
   622                   _compile_id(ci_env->compile_id()),
   623                   _save_argument_registers(false),
   624                   _stub_name(NULL),
   625                   _stub_function(NULL),
   626                   _stub_entry_point(NULL),
   627                   _method(target),
   628                   _entry_bci(osr_bci),
   629                   _initial_gvn(NULL),
   630                   _for_igvn(NULL),
   631                   _warm_calls(NULL),
   632                   _subsume_loads(subsume_loads),
   633                   _do_escape_analysis(do_escape_analysis),
   634                   _eliminate_boxing(eliminate_boxing),
   635                   _failure_reason(NULL),
   636                   _code_buffer("Compile::Fill_buffer"),
   637                   _orig_pc_slot(0),
   638                   _orig_pc_slot_offset_in_bytes(0),
   639                   _has_method_handle_invokes(false),
   640                   _mach_constant_base_node(NULL),
   641                   _node_bundling_limit(0),
   642                   _node_bundling_base(NULL),
   643                   _java_calls(0),
   644                   _inner_loops(0),
   645                   _scratch_const_size(-1),
   646                   _in_scratch_emit_size(false),
   647                   _dead_node_list(comp_arena()),
   648                   _dead_node_count(0),
   649 #ifndef PRODUCT
   650                   _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
   651                   _in_dump_cnt(0),
   652                   _printer(IdealGraphPrinter::printer()),
   653 #endif
   654                   _congraph(NULL),
   655                   _replay_inline_data(NULL),
   656                   _late_inlines(comp_arena(), 2, 0, NULL),
   657                   _string_late_inlines(comp_arena(), 2, 0, NULL),
   658                   _boxing_late_inlines(comp_arena(), 2, 0, NULL),
   659                   _late_inlines_pos(0),
   660                   _number_of_mh_late_inlines(0),
   661                   _inlining_progress(false),
   662                   _inlining_incrementally(false),
   663                   _print_inlining_list(NULL),
   664                   _print_inlining_idx(0),
   665                   _preserve_jvm_state(0) {
   666   C = this;
   668   CompileWrapper cw(this);
   669 #ifndef PRODUCT
   670   if (TimeCompiler2) {
   671     tty->print(" ");
   672     target->holder()->name()->print();
   673     tty->print(".");
   674     target->print_short_name();
   675     tty->print("  ");
   676   }
   677   TraceTime t1("Total compilation time", &_t_totalCompilation, TimeCompiler, TimeCompiler2);
   678   TraceTime t2(NULL, &_t_methodCompilation, TimeCompiler, false);
   679   bool print_opto_assembly = PrintOptoAssembly || _method->has_option("PrintOptoAssembly");
   680   if (!print_opto_assembly) {
   681     bool print_assembly = (PrintAssembly || _method->should_print_assembly());
   682     if (print_assembly && !Disassembler::can_decode()) {
   683       tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
   684       print_opto_assembly = true;
   685     }
   686   }
   687   set_print_assembly(print_opto_assembly);
   688   set_parsed_irreducible_loop(false);
   690   if (method()->has_option("ReplayInline")) {
   691     _replay_inline_data = ciReplay::load_inline_data(method(), entry_bci(), ci_env->comp_level());
   692   }
   693 #endif
   694   set_print_inlining(PrintInlining || method()->has_option("PrintInlining") NOT_PRODUCT( || PrintOptoInlining));
   695   set_print_intrinsics(PrintIntrinsics || method()->has_option("PrintIntrinsics"));
   697   if (ProfileTraps) {
   698     // Make sure the method being compiled gets its own MDO,
   699     // so we can at least track the decompile_count().
   700     method()->ensure_method_data();
   701   }
   703   Init(::AliasLevel);
   706   print_compile_messages();
   708   _ilt = InlineTree::build_inline_tree_root();
   710   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
   711   assert(num_alias_types() >= AliasIdxRaw, "");
   713 #define MINIMUM_NODE_HASH  1023
   714   // Node list that Iterative GVN will start with
   715   Unique_Node_List for_igvn(comp_arena());
   716   set_for_igvn(&for_igvn);
   718   // GVN that will be run immediately on new nodes
   719   uint estimated_size = method()->code_size()*4+64;
   720   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
   721   PhaseGVN gvn(node_arena(), estimated_size);
   722   set_initial_gvn(&gvn);
   724   if (print_inlining() || print_intrinsics()) {
   725     _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
   726   }
   727   { // Scope for timing the parser
   728     TracePhase t3("parse", &_t_parser, true);
   730     // Put top into the hash table ASAP.
   731     initial_gvn()->transform_no_reclaim(top());
   733     // Set up tf(), start(), and find a CallGenerator.
   734     CallGenerator* cg = NULL;
   735     if (is_osr_compilation()) {
   736       const TypeTuple *domain = StartOSRNode::osr_domain();
   737       const TypeTuple *range = TypeTuple::make_range(method()->signature());
   738       init_tf(TypeFunc::make(domain, range));
   739       StartNode* s = new (this) StartOSRNode(root(), domain);
   740       initial_gvn()->set_type_bottom(s);
   741       init_start(s);
   742       cg = CallGenerator::for_osr(method(), entry_bci());
   743     } else {
   744       // Normal case.
   745       init_tf(TypeFunc::make(method()));
   746       StartNode* s = new (this) StartNode(root(), tf()->domain());
   747       initial_gvn()->set_type_bottom(s);
   748       init_start(s);
   749       if (method()->intrinsic_id() == vmIntrinsics::_Reference_get && UseG1GC) {
   750         // With java.lang.ref.reference.get() we must go through the
   751         // intrinsic when G1 is enabled - even when get() is the root
   752         // method of the compile - so that, if necessary, the value in
   753         // the referent field of the reference object gets recorded by
   754         // the pre-barrier code.
   755         // Specifically, if G1 is enabled, the value in the referent
   756         // field is recorded by the G1 SATB pre barrier. This will
   757         // result in the referent being marked live and the reference
   758         // object removed from the list of discovered references during
   759         // reference processing.
   760         cg = find_intrinsic(method(), false);
   761       }
   762       if (cg == NULL) {
   763         float past_uses = method()->interpreter_invocation_count();
   764         float expected_uses = past_uses;
   765         cg = CallGenerator::for_inline(method(), expected_uses);
   766       }
   767     }
   768     if (failing())  return;
   769     if (cg == NULL) {
   770       record_method_not_compilable_all_tiers("cannot parse method");
   771       return;
   772     }
   773     JVMState* jvms = build_start_state(start(), tf());
   774     if ((jvms = cg->generate(jvms, NULL)) == NULL) {
   775       record_method_not_compilable("method parse failed");
   776       return;
   777     }
   778     GraphKit kit(jvms);
   780     if (!kit.stopped()) {
   781       // Accept return values, and transfer control we know not where.
   782       // This is done by a special, unique ReturnNode bound to root.
   783       return_values(kit.jvms());
   784     }
   786     if (kit.has_exceptions()) {
   787       // Any exceptions that escape from this call must be rethrown
   788       // to whatever caller is dynamically above us on the stack.
   789       // This is done by a special, unique RethrowNode bound to root.
   790       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
   791     }
   793     assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
   795     if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
   796       inline_string_calls(true);
   797     }
   799     if (failing())  return;
   801     print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
   803     // Remove clutter produced by parsing.
   804     if (!failing()) {
   805       ResourceMark rm;
   806       PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
   807     }
   808   }
   810   // Note:  Large methods are capped off in do_one_bytecode().
   811   if (failing())  return;
   813   // After parsing, node notes are no longer automagic.
   814   // They must be propagated by register_new_node_with_optimizer(),
   815   // clone(), or the like.
   816   set_default_node_notes(NULL);
   818   for (;;) {
   819     int successes = Inline_Warm();
   820     if (failing())  return;
   821     if (successes == 0)  break;
   822   }
   824   // Drain the list.
   825   Finish_Warm();
   826 #ifndef PRODUCT
   827   if (_printer) {
   828     _printer->print_inlining(this);
   829   }
   830 #endif
   832   if (failing())  return;
   833   NOT_PRODUCT( verify_graph_edges(); )
   835   // Now optimize
   836   Optimize();
   837   if (failing())  return;
   838   NOT_PRODUCT( verify_graph_edges(); )
   840 #ifndef PRODUCT
   841   if (PrintIdeal) {
   842     ttyLocker ttyl;  // keep the following output all in one block
   843     // This output goes directly to the tty, not the compiler log.
   844     // To enable tools to match it up with the compilation activity,
   845     // be sure to tag this tty output with the compile ID.
   846     if (xtty != NULL) {
   847       xtty->head("ideal compile_id='%d'%s", compile_id(),
   848                  is_osr_compilation()    ? " compile_kind='osr'" :
   849                  "");
   850     }
   851     root()->dump(9999);
   852     if (xtty != NULL) {
   853       xtty->tail("ideal");
   854     }
   855   }
   856 #endif
   858   NOT_PRODUCT( verify_barriers(); )
   860   // Dump compilation data to replay it.
   861   if (method()->has_option("DumpReplay")) {
   862     env()->dump_replay_data(_compile_id);
   863   }
   864   if (method()->has_option("DumpInline") && (ilt() != NULL)) {
   865     env()->dump_inline_data(_compile_id);
   866   }
   868   // Now that we know the size of all the monitors we can add a fixed slot
   869   // for the original deopt pc.
   871   _orig_pc_slot =  fixed_slots();
   872   int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
   873   set_fixed_slots(next_slot);
   875   // Compute when to use implicit null checks. Used by matching trap based
   876   // nodes and NullCheck optimization.
   877   set_allowed_deopt_reasons();
   879   // Now generate code
   880   Code_Gen();
   881   if (failing())  return;
   883   // Check if we want to skip execution of all compiled code.
   884   {
   885 #ifndef PRODUCT
   886     if (OptoNoExecute) {
   887       record_method_not_compilable("+OptoNoExecute");  // Flag as failed
   888       return;
   889     }
   890     TracePhase t2("install_code", &_t_registerMethod, TimeCompiler);
   891 #endif
   893     if (is_osr_compilation()) {
   894       _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
   895       _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
   896     } else {
   897       _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
   898       _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
   899     }
   901     env()->register_method(_method, _entry_bci,
   902                            &_code_offsets,
   903                            _orig_pc_slot_offset_in_bytes,
   904                            code_buffer(),
   905                            frame_size_in_words(), _oop_map_set,
   906                            &_handler_table, &_inc_table,
   907                            compiler,
   908                            env()->comp_level(),
   909                            has_unsafe_access(),
   910                            SharedRuntime::is_wide_vector(max_vector_size())
   911                            );
   913     if (log() != NULL) // Print code cache state into compiler log
   914       log()->code_cache_state();
   915   }
   916 }
   918 //------------------------------Compile----------------------------------------
   919 // Compile a runtime stub
   920 Compile::Compile( ciEnv* ci_env,
   921                   TypeFunc_generator generator,
   922                   address stub_function,
   923                   const char *stub_name,
   924                   int is_fancy_jump,
   925                   bool pass_tls,
   926                   bool save_arg_registers,
   927                   bool return_pc )
   928   : Phase(Compiler),
   929     _env(ci_env),
   930     _log(ci_env->log()),
   931     _compile_id(0),
   932     _save_argument_registers(save_arg_registers),
   933     _method(NULL),
   934     _stub_name(stub_name),
   935     _stub_function(stub_function),
   936     _stub_entry_point(NULL),
   937     _entry_bci(InvocationEntryBci),
   938     _initial_gvn(NULL),
   939     _for_igvn(NULL),
   940     _warm_calls(NULL),
   941     _orig_pc_slot(0),
   942     _orig_pc_slot_offset_in_bytes(0),
   943     _subsume_loads(true),
   944     _do_escape_analysis(false),
   945     _eliminate_boxing(false),
   946     _failure_reason(NULL),
   947     _code_buffer("Compile::Fill_buffer"),
   948     _has_method_handle_invokes(false),
   949     _mach_constant_base_node(NULL),
   950     _node_bundling_limit(0),
   951     _node_bundling_base(NULL),
   952     _java_calls(0),
   953     _inner_loops(0),
   954 #ifndef PRODUCT
   955     _trace_opto_output(TraceOptoOutput),
   956     _in_dump_cnt(0),
   957     _printer(NULL),
   958 #endif
   959     _dead_node_list(comp_arena()),
   960     _dead_node_count(0),
   961     _congraph(NULL),
   962     _replay_inline_data(NULL),
   963     _number_of_mh_late_inlines(0),
   964     _inlining_progress(false),
   965     _inlining_incrementally(false),
   966     _print_inlining_list(NULL),
   967     _print_inlining_idx(0),
   968     _preserve_jvm_state(0),
   969     _allowed_reasons(0) {
   970   C = this;
   972 #ifndef PRODUCT
   973   TraceTime t1(NULL, &_t_totalCompilation, TimeCompiler, false);
   974   TraceTime t2(NULL, &_t_stubCompilation, TimeCompiler, false);
   975   set_print_assembly(PrintFrameConverterAssembly);
   976   set_parsed_irreducible_loop(false);
   977 #endif
   978   CompileWrapper cw(this);
   979   Init(/*AliasLevel=*/ 0);
   980   init_tf((*generator)());
   982   {
   983     // The following is a dummy for the sake of GraphKit::gen_stub
   984     Unique_Node_List for_igvn(comp_arena());
   985     set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
   986     PhaseGVN gvn(Thread::current()->resource_area(),255);
   987     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
   988     gvn.transform_no_reclaim(top());
   990     GraphKit kit;
   991     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
   992   }
   994   NOT_PRODUCT( verify_graph_edges(); )
   995   Code_Gen();
   996   if (failing())  return;
   999   // Entry point will be accessed using compile->stub_entry_point();
  1000   if (code_buffer() == NULL) {
  1001     Matcher::soft_match_failure();
  1002   } else {
  1003     if (PrintAssembly && (WizardMode || Verbose))
  1004       tty->print_cr("### Stub::%s", stub_name);
  1006     if (!failing()) {
  1007       assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
  1009       // Make the NMethod
  1010       // For now we mark the frame as never safe for profile stackwalking
  1011       RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
  1012                                                       code_buffer(),
  1013                                                       CodeOffsets::frame_never_safe,
  1014                                                       // _code_offsets.value(CodeOffsets::Frame_Complete),
  1015                                                       frame_size_in_words(),
  1016                                                       _oop_map_set,
  1017                                                       save_arg_registers);
  1018       assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
  1020       _stub_entry_point = rs->entry_point();
  1025 //------------------------------Init-------------------------------------------
  1026 // Prepare for a single compilation
  1027 void Compile::Init(int aliaslevel) {
  1028   _unique  = 0;
  1029   _regalloc = NULL;
  1031   _tf      = NULL;  // filled in later
  1032   _top     = NULL;  // cached later
  1033   _matcher = NULL;  // filled in later
  1034   _cfg     = NULL;  // filled in later
  1036   set_24_bit_selection_and_mode(Use24BitFP, false);
  1038   _node_note_array = NULL;
  1039   _default_node_notes = NULL;
  1041   _immutable_memory = NULL; // filled in at first inquiry
  1043   // Globally visible Nodes
  1044   // First set TOP to NULL to give safe behavior during creation of RootNode
  1045   set_cached_top_node(NULL);
  1046   set_root(new (this) RootNode());
  1047   // Now that you have a Root to point to, create the real TOP
  1048   set_cached_top_node( new (this) ConNode(Type::TOP) );
  1049   set_recent_alloc(NULL, NULL);
  1051   // Create Debug Information Recorder to record scopes, oopmaps, etc.
  1052   env()->set_oop_recorder(new OopRecorder(env()->arena()));
  1053   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
  1054   env()->set_dependencies(new Dependencies(env()));
  1056   _fixed_slots = 0;
  1057   set_has_split_ifs(false);
  1058   set_has_loops(has_method() && method()->has_loops()); // first approximation
  1059   set_has_stringbuilder(false);
  1060   set_has_boxed_value(false);
  1061   _trap_can_recompile = false;  // no traps emitted yet
  1062   _major_progress = true; // start out assuming good things will happen
  1063   set_has_unsafe_access(false);
  1064   set_max_vector_size(0);
  1065   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
  1066   set_decompile_count(0);
  1068   set_do_freq_based_layout(BlockLayoutByFrequency || method_has_option("BlockLayoutByFrequency"));
  1069   set_num_loop_opts(LoopOptsCount);
  1070   set_do_inlining(Inline);
  1071   set_max_inline_size(MaxInlineSize);
  1072   set_freq_inline_size(FreqInlineSize);
  1073   set_do_scheduling(OptoScheduling);
  1074   set_do_count_invocations(false);
  1075   set_do_method_data_update(false);
  1077   if (debug_info()->recording_non_safepoints()) {
  1078     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
  1079                         (comp_arena(), 8, 0, NULL));
  1080     set_default_node_notes(Node_Notes::make(this));
  1083   // // -- Initialize types before each compile --
  1084   // // Update cached type information
  1085   // if( _method && _method->constants() )
  1086   //   Type::update_loaded_types(_method, _method->constants());
  1088   // Init alias_type map.
  1089   if (!_do_escape_analysis && aliaslevel == 3)
  1090     aliaslevel = 2;  // No unique types without escape analysis
  1091   _AliasLevel = aliaslevel;
  1092   const int grow_ats = 16;
  1093   _max_alias_types = grow_ats;
  1094   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
  1095   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
  1096   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
  1098     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
  1100   // Initialize the first few types.
  1101   _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
  1102   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
  1103   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
  1104   _num_alias_types = AliasIdxRaw+1;
  1105   // Zero out the alias type cache.
  1106   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
  1107   // A NULL adr_type hits in the cache right away.  Preload the right answer.
  1108   probe_alias_cache(NULL)->_index = AliasIdxTop;
  1110   _intrinsics = NULL;
  1111   _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1112   _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1113   _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
  1114   register_library_intrinsics();
  1117 //---------------------------init_start----------------------------------------
  1118 // Install the StartNode on this compile object.
  1119 void Compile::init_start(StartNode* s) {
  1120   if (failing())
  1121     return; // already failing
  1122   assert(s == start(), "");
  1125 StartNode* Compile::start() const {
  1126   assert(!failing(), "");
  1127   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
  1128     Node* start = root()->fast_out(i);
  1129     if( start->is_Start() )
  1130       return start->as_Start();
  1132   ShouldNotReachHere();
  1133   return NULL;
  1136 //-------------------------------immutable_memory-------------------------------------
  1137 // Access immutable memory
  1138 Node* Compile::immutable_memory() {
  1139   if (_immutable_memory != NULL) {
  1140     return _immutable_memory;
  1142   StartNode* s = start();
  1143   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
  1144     Node *p = s->fast_out(i);
  1145     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
  1146       _immutable_memory = p;
  1147       return _immutable_memory;
  1150   ShouldNotReachHere();
  1151   return NULL;
  1154 //----------------------set_cached_top_node------------------------------------
  1155 // Install the cached top node, and make sure Node::is_top works correctly.
  1156 void Compile::set_cached_top_node(Node* tn) {
  1157   if (tn != NULL)  verify_top(tn);
  1158   Node* old_top = _top;
  1159   _top = tn;
  1160   // Calling Node::setup_is_top allows the nodes the chance to adjust
  1161   // their _out arrays.
  1162   if (_top != NULL)     _top->setup_is_top();
  1163   if (old_top != NULL)  old_top->setup_is_top();
  1164   assert(_top == NULL || top()->is_top(), "");
  1167 #ifdef ASSERT
  1168 uint Compile::count_live_nodes_by_graph_walk() {
  1169   Unique_Node_List useful(comp_arena());
  1170   // Get useful node list by walking the graph.
  1171   identify_useful_nodes(useful);
  1172   return useful.size();
  1175 void Compile::print_missing_nodes() {
  1177   // Return if CompileLog is NULL and PrintIdealNodeCount is false.
  1178   if ((_log == NULL) && (! PrintIdealNodeCount)) {
  1179     return;
  1182   // This is an expensive function. It is executed only when the user
  1183   // specifies VerifyIdealNodeCount option or otherwise knows the
  1184   // additional work that needs to be done to identify reachable nodes
  1185   // by walking the flow graph and find the missing ones using
  1186   // _dead_node_list.
  1188   Unique_Node_List useful(comp_arena());
  1189   // Get useful node list by walking the graph.
  1190   identify_useful_nodes(useful);
  1192   uint l_nodes = C->live_nodes();
  1193   uint l_nodes_by_walk = useful.size();
  1195   if (l_nodes != l_nodes_by_walk) {
  1196     if (_log != NULL) {
  1197       _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
  1198       _log->stamp();
  1199       _log->end_head();
  1201     VectorSet& useful_member_set = useful.member_set();
  1202     int last_idx = l_nodes_by_walk;
  1203     for (int i = 0; i < last_idx; i++) {
  1204       if (useful_member_set.test(i)) {
  1205         if (_dead_node_list.test(i)) {
  1206           if (_log != NULL) {
  1207             _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
  1209           if (PrintIdealNodeCount) {
  1210             // Print the log message to tty
  1211               tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
  1212               useful.at(i)->dump();
  1216       else if (! _dead_node_list.test(i)) {
  1217         if (_log != NULL) {
  1218           _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
  1220         if (PrintIdealNodeCount) {
  1221           // Print the log message to tty
  1222           tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
  1226     if (_log != NULL) {
  1227       _log->tail("mismatched_nodes");
  1231 #endif
  1233 #ifndef PRODUCT
  1234 void Compile::verify_top(Node* tn) const {
  1235   if (tn != NULL) {
  1236     assert(tn->is_Con(), "top node must be a constant");
  1237     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
  1238     assert(tn->in(0) != NULL, "must have live top node");
  1241 #endif
  1244 ///-------------------Managing Per-Node Debug & Profile Info-------------------
  1246 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
  1247   guarantee(arr != NULL, "");
  1248   int num_blocks = arr->length();
  1249   if (grow_by < num_blocks)  grow_by = num_blocks;
  1250   int num_notes = grow_by * _node_notes_block_size;
  1251   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
  1252   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
  1253   while (num_notes > 0) {
  1254     arr->append(notes);
  1255     notes     += _node_notes_block_size;
  1256     num_notes -= _node_notes_block_size;
  1258   assert(num_notes == 0, "exact multiple, please");
  1261 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
  1262   if (source == NULL || dest == NULL)  return false;
  1264   if (dest->is_Con())
  1265     return false;               // Do not push debug info onto constants.
  1267 #ifdef ASSERT
  1268   // Leave a bread crumb trail pointing to the original node:
  1269   if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
  1270     dest->set_debug_orig(source);
  1272 #endif
  1274   if (node_note_array() == NULL)
  1275     return false;               // Not collecting any notes now.
  1277   // This is a copy onto a pre-existing node, which may already have notes.
  1278   // If both nodes have notes, do not overwrite any pre-existing notes.
  1279   Node_Notes* source_notes = node_notes_at(source->_idx);
  1280   if (source_notes == NULL || source_notes->is_clear())  return false;
  1281   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
  1282   if (dest_notes == NULL || dest_notes->is_clear()) {
  1283     return set_node_notes_at(dest->_idx, source_notes);
  1286   Node_Notes merged_notes = (*source_notes);
  1287   // The order of operations here ensures that dest notes will win...
  1288   merged_notes.update_from(dest_notes);
  1289   return set_node_notes_at(dest->_idx, &merged_notes);
  1293 //--------------------------allow_range_check_smearing-------------------------
  1294 // Gating condition for coalescing similar range checks.
  1295 // Sometimes we try 'speculatively' replacing a series of a range checks by a
  1296 // single covering check that is at least as strong as any of them.
  1297 // If the optimization succeeds, the simplified (strengthened) range check
  1298 // will always succeed.  If it fails, we will deopt, and then give up
  1299 // on the optimization.
  1300 bool Compile::allow_range_check_smearing() const {
  1301   // If this method has already thrown a range-check,
  1302   // assume it was because we already tried range smearing
  1303   // and it failed.
  1304   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
  1305   return !already_trapped;
  1309 //------------------------------flatten_alias_type-----------------------------
  1310 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
  1311   int offset = tj->offset();
  1312   TypePtr::PTR ptr = tj->ptr();
  1314   // Known instance (scalarizable allocation) alias only with itself.
  1315   bool is_known_inst = tj->isa_oopptr() != NULL &&
  1316                        tj->is_oopptr()->is_known_instance();
  1318   // Process weird unsafe references.
  1319   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
  1320     assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
  1321     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
  1322     tj = TypeOopPtr::BOTTOM;
  1323     ptr = tj->ptr();
  1324     offset = tj->offset();
  1327   // Array pointers need some flattening
  1328   const TypeAryPtr *ta = tj->isa_aryptr();
  1329   if (ta && ta->is_stable()) {
  1330     // Erase stability property for alias analysis.
  1331     tj = ta = ta->cast_to_stable(false);
  1333   if( ta && is_known_inst ) {
  1334     if ( offset != Type::OffsetBot &&
  1335          offset > arrayOopDesc::length_offset_in_bytes() ) {
  1336       offset = Type::OffsetBot; // Flatten constant access into array body only
  1337       tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
  1339   } else if( ta && _AliasLevel >= 2 ) {
  1340     // For arrays indexed by constant indices, we flatten the alias
  1341     // space to include all of the array body.  Only the header, klass
  1342     // and array length can be accessed un-aliased.
  1343     if( offset != Type::OffsetBot ) {
  1344       if( ta->const_oop() ) { // MethodData* or Method*
  1345         offset = Type::OffsetBot;   // Flatten constant access into array body
  1346         tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
  1347       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
  1348         // range is OK as-is.
  1349         tj = ta = TypeAryPtr::RANGE;
  1350       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
  1351         tj = TypeInstPtr::KLASS; // all klass loads look alike
  1352         ta = TypeAryPtr::RANGE; // generic ignored junk
  1353         ptr = TypePtr::BotPTR;
  1354       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
  1355         tj = TypeInstPtr::MARK;
  1356         ta = TypeAryPtr::RANGE; // generic ignored junk
  1357         ptr = TypePtr::BotPTR;
  1358       } else {                  // Random constant offset into array body
  1359         offset = Type::OffsetBot;   // Flatten constant access into array body
  1360         tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
  1363     // Arrays of fixed size alias with arrays of unknown size.
  1364     if (ta->size() != TypeInt::POS) {
  1365       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
  1366       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
  1368     // Arrays of known objects become arrays of unknown objects.
  1369     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
  1370       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
  1371       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
  1373     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
  1374       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
  1375       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
  1377     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
  1378     // cannot be distinguished by bytecode alone.
  1379     if (ta->elem() == TypeInt::BOOL) {
  1380       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
  1381       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
  1382       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
  1384     // During the 2nd round of IterGVN, NotNull castings are removed.
  1385     // Make sure the Bottom and NotNull variants alias the same.
  1386     // Also, make sure exact and non-exact variants alias the same.
  1387     if (ptr == TypePtr::NotNull || ta->klass_is_exact() || ta->speculative() != NULL) {
  1388       tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
  1392   // Oop pointers need some flattening
  1393   const TypeInstPtr *to = tj->isa_instptr();
  1394   if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
  1395     ciInstanceKlass *k = to->klass()->as_instance_klass();
  1396     if( ptr == TypePtr::Constant ) {
  1397       if (to->klass() != ciEnv::current()->Class_klass() ||
  1398           offset < k->size_helper() * wordSize) {
  1399         // No constant oop pointers (such as Strings); they alias with
  1400         // unknown strings.
  1401         assert(!is_known_inst, "not scalarizable allocation");
  1402         tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
  1404     } else if( is_known_inst ) {
  1405       tj = to; // Keep NotNull and klass_is_exact for instance type
  1406     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
  1407       // During the 2nd round of IterGVN, NotNull castings are removed.
  1408       // Make sure the Bottom and NotNull variants alias the same.
  1409       // Also, make sure exact and non-exact variants alias the same.
  1410       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
  1412     if (to->speculative() != NULL) {
  1413       tj = to = TypeInstPtr::make(to->ptr(),to->klass(),to->klass_is_exact(),to->const_oop(),to->offset(), to->instance_id());
  1415     // Canonicalize the holder of this field
  1416     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
  1417       // First handle header references such as a LoadKlassNode, even if the
  1418       // object's klass is unloaded at compile time (4965979).
  1419       if (!is_known_inst) { // Do it only for non-instance types
  1420         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
  1422     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
  1423       // Static fields are in the space above the normal instance
  1424       // fields in the java.lang.Class instance.
  1425       if (to->klass() != ciEnv::current()->Class_klass()) {
  1426         to = NULL;
  1427         tj = TypeOopPtr::BOTTOM;
  1428         offset = tj->offset();
  1430     } else {
  1431       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
  1432       if (!k->equals(canonical_holder) || tj->offset() != offset) {
  1433         if( is_known_inst ) {
  1434           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
  1435         } else {
  1436           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
  1442   // Klass pointers to object array klasses need some flattening
  1443   const TypeKlassPtr *tk = tj->isa_klassptr();
  1444   if( tk ) {
  1445     // If we are referencing a field within a Klass, we need
  1446     // to assume the worst case of an Object.  Both exact and
  1447     // inexact types must flatten to the same alias class so
  1448     // use NotNull as the PTR.
  1449     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
  1451       tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
  1452                                    TypeKlassPtr::OBJECT->klass(),
  1453                                    offset);
  1456     ciKlass* klass = tk->klass();
  1457     if( klass->is_obj_array_klass() ) {
  1458       ciKlass* k = TypeAryPtr::OOPS->klass();
  1459       if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
  1460         k = TypeInstPtr::BOTTOM->klass();
  1461       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
  1464     // Check for precise loads from the primary supertype array and force them
  1465     // to the supertype cache alias index.  Check for generic array loads from
  1466     // the primary supertype array and also force them to the supertype cache
  1467     // alias index.  Since the same load can reach both, we need to merge
  1468     // these 2 disparate memories into the same alias class.  Since the
  1469     // primary supertype array is read-only, there's no chance of confusion
  1470     // where we bypass an array load and an array store.
  1471     int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
  1472     if (offset == Type::OffsetBot ||
  1473         (offset >= primary_supers_offset &&
  1474          offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
  1475         offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
  1476       offset = in_bytes(Klass::secondary_super_cache_offset());
  1477       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
  1481   // Flatten all Raw pointers together.
  1482   if (tj->base() == Type::RawPtr)
  1483     tj = TypeRawPtr::BOTTOM;
  1485   if (tj->base() == Type::AnyPtr)
  1486     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
  1488   // Flatten all to bottom for now
  1489   switch( _AliasLevel ) {
  1490   case 0:
  1491     tj = TypePtr::BOTTOM;
  1492     break;
  1493   case 1:                       // Flatten to: oop, static, field or array
  1494     switch (tj->base()) {
  1495     //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
  1496     case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
  1497     case Type::AryPtr:   // do not distinguish arrays at all
  1498     case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
  1499     case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
  1500     case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
  1501     default: ShouldNotReachHere();
  1503     break;
  1504   case 2:                       // No collapsing at level 2; keep all splits
  1505   case 3:                       // No collapsing at level 3; keep all splits
  1506     break;
  1507   default:
  1508     Unimplemented();
  1511   offset = tj->offset();
  1512   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
  1514   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
  1515           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
  1516           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
  1517           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
  1518           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
  1519           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
  1520           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr)  ,
  1521           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
  1522   assert( tj->ptr() != TypePtr::TopPTR &&
  1523           tj->ptr() != TypePtr::AnyNull &&
  1524           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
  1525 //    assert( tj->ptr() != TypePtr::Constant ||
  1526 //            tj->base() == Type::RawPtr ||
  1527 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
  1529   return tj;
  1532 void Compile::AliasType::Init(int i, const TypePtr* at) {
  1533   _index = i;
  1534   _adr_type = at;
  1535   _field = NULL;
  1536   _element = NULL;
  1537   _is_rewritable = true; // default
  1538   const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
  1539   if (atoop != NULL && atoop->is_known_instance()) {
  1540     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
  1541     _general_index = Compile::current()->get_alias_index(gt);
  1542   } else {
  1543     _general_index = 0;
  1547 //---------------------------------print_on------------------------------------
  1548 #ifndef PRODUCT
  1549 void Compile::AliasType::print_on(outputStream* st) {
  1550   if (index() < 10)
  1551         st->print("@ <%d> ", index());
  1552   else  st->print("@ <%d>",  index());
  1553   st->print(is_rewritable() ? "   " : " RO");
  1554   int offset = adr_type()->offset();
  1555   if (offset == Type::OffsetBot)
  1556         st->print(" +any");
  1557   else  st->print(" +%-3d", offset);
  1558   st->print(" in ");
  1559   adr_type()->dump_on(st);
  1560   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
  1561   if (field() != NULL && tjp) {
  1562     if (tjp->klass()  != field()->holder() ||
  1563         tjp->offset() != field()->offset_in_bytes()) {
  1564       st->print(" != ");
  1565       field()->print();
  1566       st->print(" ***");
  1571 void print_alias_types() {
  1572   Compile* C = Compile::current();
  1573   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
  1574   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
  1575     C->alias_type(idx)->print_on(tty);
  1576     tty->cr();
  1579 #endif
  1582 //----------------------------probe_alias_cache--------------------------------
  1583 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
  1584   intptr_t key = (intptr_t) adr_type;
  1585   key ^= key >> logAliasCacheSize;
  1586   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
  1590 //-----------------------------grow_alias_types--------------------------------
  1591 void Compile::grow_alias_types() {
  1592   const int old_ats  = _max_alias_types; // how many before?
  1593   const int new_ats  = old_ats;          // how many more?
  1594   const int grow_ats = old_ats+new_ats;  // how many now?
  1595   _max_alias_types = grow_ats;
  1596   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
  1597   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
  1598   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
  1599   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
  1603 //--------------------------------find_alias_type------------------------------
  1604 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
  1605   if (_AliasLevel == 0)
  1606     return alias_type(AliasIdxBot);
  1608   AliasCacheEntry* ace = probe_alias_cache(adr_type);
  1609   if (ace->_adr_type == adr_type) {
  1610     return alias_type(ace->_index);
  1613   // Handle special cases.
  1614   if (adr_type == NULL)             return alias_type(AliasIdxTop);
  1615   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
  1617   // Do it the slow way.
  1618   const TypePtr* flat = flatten_alias_type(adr_type);
  1620 #ifdef ASSERT
  1621   assert(flat == flatten_alias_type(flat), "idempotent");
  1622   assert(flat != TypePtr::BOTTOM,     "cannot alias-analyze an untyped ptr");
  1623   if (flat->isa_oopptr() && !flat->isa_klassptr()) {
  1624     const TypeOopPtr* foop = flat->is_oopptr();
  1625     // Scalarizable allocations have exact klass always.
  1626     bool exact = !foop->klass_is_exact() || foop->is_known_instance();
  1627     const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
  1628     assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type");
  1630   assert(flat == flatten_alias_type(flat), "exact bit doesn't matter");
  1631 #endif
  1633   int idx = AliasIdxTop;
  1634   for (int i = 0; i < num_alias_types(); i++) {
  1635     if (alias_type(i)->adr_type() == flat) {
  1636       idx = i;
  1637       break;
  1641   if (idx == AliasIdxTop) {
  1642     if (no_create)  return NULL;
  1643     // Grow the array if necessary.
  1644     if (_num_alias_types == _max_alias_types)  grow_alias_types();
  1645     // Add a new alias type.
  1646     idx = _num_alias_types++;
  1647     _alias_types[idx]->Init(idx, flat);
  1648     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
  1649     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
  1650     if (flat->isa_instptr()) {
  1651       if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
  1652           && flat->is_instptr()->klass() == env()->Class_klass())
  1653         alias_type(idx)->set_rewritable(false);
  1655     if (flat->isa_aryptr()) {
  1656 #ifdef ASSERT
  1657       const int header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
  1658       // (T_BYTE has the weakest alignment and size restrictions...)
  1659       assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
  1660 #endif
  1661       if (flat->offset() == TypePtr::OffsetBot) {
  1662         alias_type(idx)->set_element(flat->is_aryptr()->elem());
  1665     if (flat->isa_klassptr()) {
  1666       if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
  1667         alias_type(idx)->set_rewritable(false);
  1668       if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
  1669         alias_type(idx)->set_rewritable(false);
  1670       if (flat->offset() == in_bytes(Klass::access_flags_offset()))
  1671         alias_type(idx)->set_rewritable(false);
  1672       if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
  1673         alias_type(idx)->set_rewritable(false);
  1675     // %%% (We would like to finalize JavaThread::threadObj_offset(),
  1676     // but the base pointer type is not distinctive enough to identify
  1677     // references into JavaThread.)
  1679     // Check for final fields.
  1680     const TypeInstPtr* tinst = flat->isa_instptr();
  1681     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
  1682       ciField* field;
  1683       if (tinst->const_oop() != NULL &&
  1684           tinst->klass() == ciEnv::current()->Class_klass() &&
  1685           tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
  1686         // static field
  1687         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
  1688         field = k->get_field_by_offset(tinst->offset(), true);
  1689       } else {
  1690         ciInstanceKlass *k = tinst->klass()->as_instance_klass();
  1691         field = k->get_field_by_offset(tinst->offset(), false);
  1693       assert(field == NULL ||
  1694              original_field == NULL ||
  1695              (field->holder() == original_field->holder() &&
  1696               field->offset() == original_field->offset() &&
  1697               field->is_static() == original_field->is_static()), "wrong field?");
  1698       // Set field() and is_rewritable() attributes.
  1699       if (field != NULL)  alias_type(idx)->set_field(field);
  1703   // Fill the cache for next time.
  1704   ace->_adr_type = adr_type;
  1705   ace->_index    = idx;
  1706   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
  1708   // Might as well try to fill the cache for the flattened version, too.
  1709   AliasCacheEntry* face = probe_alias_cache(flat);
  1710   if (face->_adr_type == NULL) {
  1711     face->_adr_type = flat;
  1712     face->_index    = idx;
  1713     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
  1716   return alias_type(idx);
  1720 Compile::AliasType* Compile::alias_type(ciField* field) {
  1721   const TypeOopPtr* t;
  1722   if (field->is_static())
  1723     t = TypeInstPtr::make(field->holder()->java_mirror());
  1724   else
  1725     t = TypeOopPtr::make_from_klass_raw(field->holder());
  1726   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
  1727   assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
  1728   return atp;
  1732 //------------------------------have_alias_type--------------------------------
  1733 bool Compile::have_alias_type(const TypePtr* adr_type) {
  1734   AliasCacheEntry* ace = probe_alias_cache(adr_type);
  1735   if (ace->_adr_type == adr_type) {
  1736     return true;
  1739   // Handle special cases.
  1740   if (adr_type == NULL)             return true;
  1741   if (adr_type == TypePtr::BOTTOM)  return true;
  1743   return find_alias_type(adr_type, true, NULL) != NULL;
  1746 //-----------------------------must_alias--------------------------------------
  1747 // True if all values of the given address type are in the given alias category.
  1748 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
  1749   if (alias_idx == AliasIdxBot)         return true;  // the universal category
  1750   if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
  1751   if (alias_idx == AliasIdxTop)         return false; // the empty category
  1752   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
  1754   // the only remaining possible overlap is identity
  1755   int adr_idx = get_alias_index(adr_type);
  1756   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
  1757   assert(adr_idx == alias_idx ||
  1758          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
  1759           && adr_type                       != TypeOopPtr::BOTTOM),
  1760          "should not be testing for overlap with an unsafe pointer");
  1761   return adr_idx == alias_idx;
  1764 //------------------------------can_alias--------------------------------------
  1765 // True if any values of the given address type are in the given alias category.
  1766 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
  1767   if (alias_idx == AliasIdxTop)         return false; // the empty category
  1768   if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
  1769   if (alias_idx == AliasIdxBot)         return true;  // the universal category
  1770   if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
  1772   // the only remaining possible overlap is identity
  1773   int adr_idx = get_alias_index(adr_type);
  1774   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
  1775   return adr_idx == alias_idx;
  1780 //---------------------------pop_warm_call-------------------------------------
  1781 WarmCallInfo* Compile::pop_warm_call() {
  1782   WarmCallInfo* wci = _warm_calls;
  1783   if (wci != NULL)  _warm_calls = wci->remove_from(wci);
  1784   return wci;
  1787 //----------------------------Inline_Warm--------------------------------------
  1788 int Compile::Inline_Warm() {
  1789   // If there is room, try to inline some more warm call sites.
  1790   // %%% Do a graph index compaction pass when we think we're out of space?
  1791   if (!InlineWarmCalls)  return 0;
  1793   int calls_made_hot = 0;
  1794   int room_to_grow   = NodeCountInliningCutoff - unique();
  1795   int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
  1796   int amount_grown   = 0;
  1797   WarmCallInfo* call;
  1798   while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
  1799     int est_size = (int)call->size();
  1800     if (est_size > (room_to_grow - amount_grown)) {
  1801       // This one won't fit anyway.  Get rid of it.
  1802       call->make_cold();
  1803       continue;
  1805     call->make_hot();
  1806     calls_made_hot++;
  1807     amount_grown   += est_size;
  1808     amount_to_grow -= est_size;
  1811   if (calls_made_hot > 0)  set_major_progress();
  1812   return calls_made_hot;
  1816 //----------------------------Finish_Warm--------------------------------------
  1817 void Compile::Finish_Warm() {
  1818   if (!InlineWarmCalls)  return;
  1819   if (failing())  return;
  1820   if (warm_calls() == NULL)  return;
  1822   // Clean up loose ends, if we are out of space for inlining.
  1823   WarmCallInfo* call;
  1824   while ((call = pop_warm_call()) != NULL) {
  1825     call->make_cold();
  1829 //---------------------cleanup_loop_predicates-----------------------
  1830 // Remove the opaque nodes that protect the predicates so that all unused
  1831 // checks and uncommon_traps will be eliminated from the ideal graph
  1832 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
  1833   if (predicate_count()==0) return;
  1834   for (int i = predicate_count(); i > 0; i--) {
  1835     Node * n = predicate_opaque1_node(i-1);
  1836     assert(n->Opcode() == Op_Opaque1, "must be");
  1837     igvn.replace_node(n, n->in(1));
  1839   assert(predicate_count()==0, "should be clean!");
  1842 // StringOpts and late inlining of string methods
  1843 void Compile::inline_string_calls(bool parse_time) {
  1845     // remove useless nodes to make the usage analysis simpler
  1846     ResourceMark rm;
  1847     PhaseRemoveUseless pru(initial_gvn(), for_igvn());
  1851     ResourceMark rm;
  1852     print_method(PHASE_BEFORE_STRINGOPTS, 3);
  1853     PhaseStringOpts pso(initial_gvn(), for_igvn());
  1854     print_method(PHASE_AFTER_STRINGOPTS, 3);
  1857   // now inline anything that we skipped the first time around
  1858   if (!parse_time) {
  1859     _late_inlines_pos = _late_inlines.length();
  1862   while (_string_late_inlines.length() > 0) {
  1863     CallGenerator* cg = _string_late_inlines.pop();
  1864     cg->do_late_inline();
  1865     if (failing())  return;
  1867   _string_late_inlines.trunc_to(0);
  1870 // Late inlining of boxing methods
  1871 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
  1872   if (_boxing_late_inlines.length() > 0) {
  1873     assert(has_boxed_value(), "inconsistent");
  1875     PhaseGVN* gvn = initial_gvn();
  1876     set_inlining_incrementally(true);
  1878     assert( igvn._worklist.size() == 0, "should be done with igvn" );
  1879     for_igvn()->clear();
  1880     gvn->replace_with(&igvn);
  1882     while (_boxing_late_inlines.length() > 0) {
  1883       CallGenerator* cg = _boxing_late_inlines.pop();
  1884       cg->do_late_inline();
  1885       if (failing())  return;
  1887     _boxing_late_inlines.trunc_to(0);
  1890       ResourceMark rm;
  1891       PhaseRemoveUseless pru(gvn, for_igvn());
  1894     igvn = PhaseIterGVN(gvn);
  1895     igvn.optimize();
  1897     set_inlining_progress(false);
  1898     set_inlining_incrementally(false);
  1902 void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
  1903   assert(IncrementalInline, "incremental inlining should be on");
  1904   PhaseGVN* gvn = initial_gvn();
  1906   set_inlining_progress(false);
  1907   for_igvn()->clear();
  1908   gvn->replace_with(&igvn);
  1910   int i = 0;
  1912   for (; i <_late_inlines.length() && !inlining_progress(); i++) {
  1913     CallGenerator* cg = _late_inlines.at(i);
  1914     _late_inlines_pos = i+1;
  1915     cg->do_late_inline();
  1916     if (failing())  return;
  1918   int j = 0;
  1919   for (; i < _late_inlines.length(); i++, j++) {
  1920     _late_inlines.at_put(j, _late_inlines.at(i));
  1922   _late_inlines.trunc_to(j);
  1925     ResourceMark rm;
  1926     PhaseRemoveUseless pru(gvn, for_igvn());
  1929   igvn = PhaseIterGVN(gvn);
  1932 // Perform incremental inlining until bound on number of live nodes is reached
  1933 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
  1934   PhaseGVN* gvn = initial_gvn();
  1936   set_inlining_incrementally(true);
  1937   set_inlining_progress(true);
  1938   uint low_live_nodes = 0;
  1940   while(inlining_progress() && _late_inlines.length() > 0) {
  1942     if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
  1943       if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
  1944         // PhaseIdealLoop is expensive so we only try it once we are
  1945         // out of loop and we only try it again if the previous helped
  1946         // got the number of nodes down significantly
  1947         PhaseIdealLoop ideal_loop( igvn, false, true );
  1948         if (failing())  return;
  1949         low_live_nodes = live_nodes();
  1950         _major_progress = true;
  1953       if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
  1954         break;
  1958     inline_incrementally_one(igvn);
  1960     if (failing())  return;
  1962     igvn.optimize();
  1964     if (failing())  return;
  1967   assert( igvn._worklist.size() == 0, "should be done with igvn" );
  1969   if (_string_late_inlines.length() > 0) {
  1970     assert(has_stringbuilder(), "inconsistent");
  1971     for_igvn()->clear();
  1972     initial_gvn()->replace_with(&igvn);
  1974     inline_string_calls(false);
  1976     if (failing())  return;
  1979       ResourceMark rm;
  1980       PhaseRemoveUseless pru(initial_gvn(), for_igvn());
  1983     igvn = PhaseIterGVN(gvn);
  1985     igvn.optimize();
  1988   set_inlining_incrementally(false);
  1992 //------------------------------Optimize---------------------------------------
  1993 // Given a graph, optimize it.
  1994 void Compile::Optimize() {
  1995   TracePhase t1("optimizer", &_t_optimizer, true);
  1997 #ifndef PRODUCT
  1998   if (env()->break_at_compile()) {
  1999     BREAKPOINT;
  2002 #endif
  2004   ResourceMark rm;
  2005   int          loop_opts_cnt;
  2007   NOT_PRODUCT( verify_graph_edges(); )
  2009   print_method(PHASE_AFTER_PARSING);
  2012   // Iterative Global Value Numbering, including ideal transforms
  2013   // Initialize IterGVN with types and values from parse-time GVN
  2014   PhaseIterGVN igvn(initial_gvn());
  2016     NOT_PRODUCT( TracePhase t2("iterGVN", &_t_iterGVN, TimeCompiler); )
  2017     igvn.optimize();
  2020   print_method(PHASE_ITER_GVN1, 2);
  2022   if (failing())  return;
  2025     NOT_PRODUCT( TracePhase t2("incrementalInline", &_t_incrInline, TimeCompiler); )
  2026     inline_incrementally(igvn);
  2029   print_method(PHASE_INCREMENTAL_INLINE, 2);
  2031   if (failing())  return;
  2033   if (eliminate_boxing()) {
  2034     NOT_PRODUCT( TracePhase t2("incrementalInline", &_t_incrInline, TimeCompiler); )
  2035     // Inline valueOf() methods now.
  2036     inline_boxing_calls(igvn);
  2038     print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
  2040     if (failing())  return;
  2043   // Remove the speculative part of types and clean up the graph from
  2044   // the extra CastPP nodes whose only purpose is to carry them. Do
  2045   // that early so that optimizations are not disrupted by the extra
  2046   // CastPP nodes.
  2047   remove_speculative_types(igvn);
  2049   // No more new expensive nodes will be added to the list from here
  2050   // so keep only the actual candidates for optimizations.
  2051   cleanup_expensive_nodes(igvn);
  2053   // Perform escape analysis
  2054   if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
  2055     if (has_loops()) {
  2056       // Cleanup graph (remove dead nodes).
  2057       TracePhase t2("idealLoop", &_t_idealLoop, true);
  2058       PhaseIdealLoop ideal_loop( igvn, false, true );
  2059       if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
  2060       if (failing())  return;
  2062     ConnectionGraph::do_analysis(this, &igvn);
  2064     if (failing())  return;
  2066     // Optimize out fields loads from scalar replaceable allocations.
  2067     igvn.optimize();
  2068     print_method(PHASE_ITER_GVN_AFTER_EA, 2);
  2070     if (failing())  return;
  2072     if (congraph() != NULL && macro_count() > 0) {
  2073       NOT_PRODUCT( TracePhase t2("macroEliminate", &_t_macroEliminate, TimeCompiler); )
  2074       PhaseMacroExpand mexp(igvn);
  2075       mexp.eliminate_macro_nodes();
  2076       igvn.set_delay_transform(false);
  2078       igvn.optimize();
  2079       print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
  2081       if (failing())  return;
  2085   // Loop transforms on the ideal graph.  Range Check Elimination,
  2086   // peeling, unrolling, etc.
  2088   // Set loop opts counter
  2089   loop_opts_cnt = num_loop_opts();
  2090   if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
  2092       TracePhase t2("idealLoop", &_t_idealLoop, true);
  2093       PhaseIdealLoop ideal_loop( igvn, true );
  2094       loop_opts_cnt--;
  2095       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
  2096       if (failing())  return;
  2098     // Loop opts pass if partial peeling occurred in previous pass
  2099     if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
  2100       TracePhase t3("idealLoop", &_t_idealLoop, true);
  2101       PhaseIdealLoop ideal_loop( igvn, false );
  2102       loop_opts_cnt--;
  2103       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
  2104       if (failing())  return;
  2106     // Loop opts pass for loop-unrolling before CCP
  2107     if(major_progress() && (loop_opts_cnt > 0)) {
  2108       TracePhase t4("idealLoop", &_t_idealLoop, true);
  2109       PhaseIdealLoop ideal_loop( igvn, false );
  2110       loop_opts_cnt--;
  2111       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
  2113     if (!failing()) {
  2114       // Verify that last round of loop opts produced a valid graph
  2115       NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
  2116       PhaseIdealLoop::verify(igvn);
  2119   if (failing())  return;
  2121   // Conditional Constant Propagation;
  2122   PhaseCCP ccp( &igvn );
  2123   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
  2125     TracePhase t2("ccp", &_t_ccp, true);
  2126     ccp.do_transform();
  2128   print_method(PHASE_CPP1, 2);
  2130   assert( true, "Break here to ccp.dump_old2new_map()");
  2132   // Iterative Global Value Numbering, including ideal transforms
  2134     NOT_PRODUCT( TracePhase t2("iterGVN2", &_t_iterGVN2, TimeCompiler); )
  2135     igvn = ccp;
  2136     igvn.optimize();
  2139   print_method(PHASE_ITER_GVN2, 2);
  2141   if (failing())  return;
  2143   // Loop transforms on the ideal graph.  Range Check Elimination,
  2144   // peeling, unrolling, etc.
  2145   if(loop_opts_cnt > 0) {
  2146     debug_only( int cnt = 0; );
  2147     while(major_progress() && (loop_opts_cnt > 0)) {
  2148       TracePhase t2("idealLoop", &_t_idealLoop, true);
  2149       assert( cnt++ < 40, "infinite cycle in loop optimization" );
  2150       PhaseIdealLoop ideal_loop( igvn, true);
  2151       loop_opts_cnt--;
  2152       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
  2153       if (failing())  return;
  2158     // Verify that all previous optimizations produced a valid graph
  2159     // at least to this point, even if no loop optimizations were done.
  2160     NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
  2161     PhaseIdealLoop::verify(igvn);
  2165     NOT_PRODUCT( TracePhase t2("macroExpand", &_t_macroExpand, TimeCompiler); )
  2166     PhaseMacroExpand  mex(igvn);
  2167     if (mex.expand_macro_nodes()) {
  2168       assert(failing(), "must bail out w/ explicit message");
  2169       return;
  2173  } // (End scope of igvn; run destructor if necessary for asserts.)
  2175   dump_inlining();
  2176   // A method with only infinite loops has no edges entering loops from root
  2178     NOT_PRODUCT( TracePhase t2("graphReshape", &_t_graphReshaping, TimeCompiler); )
  2179     if (final_graph_reshaping()) {
  2180       assert(failing(), "must bail out w/ explicit message");
  2181       return;
  2185   print_method(PHASE_OPTIMIZE_FINISHED, 2);
  2189 //------------------------------Code_Gen---------------------------------------
  2190 // Given a graph, generate code for it
  2191 void Compile::Code_Gen() {
  2192   if (failing()) {
  2193     return;
  2196   // Perform instruction selection.  You might think we could reclaim Matcher
  2197   // memory PDQ, but actually the Matcher is used in generating spill code.
  2198   // Internals of the Matcher (including some VectorSets) must remain live
  2199   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
  2200   // set a bit in reclaimed memory.
  2202   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
  2203   // nodes.  Mapping is only valid at the root of each matched subtree.
  2204   NOT_PRODUCT( verify_graph_edges(); )
  2206   Matcher matcher;
  2207   _matcher = &matcher;
  2209     TracePhase t2("matcher", &_t_matcher, true);
  2210     matcher.match();
  2212   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
  2213   // nodes.  Mapping is only valid at the root of each matched subtree.
  2214   NOT_PRODUCT( verify_graph_edges(); )
  2216   // If you have too many nodes, or if matching has failed, bail out
  2217   check_node_count(0, "out of nodes matching instructions");
  2218   if (failing()) {
  2219     return;
  2222   // Build a proper-looking CFG
  2223   PhaseCFG cfg(node_arena(), root(), matcher);
  2224   _cfg = &cfg;
  2226     NOT_PRODUCT( TracePhase t2("scheduler", &_t_scheduler, TimeCompiler); )
  2227     bool success = cfg.do_global_code_motion();
  2228     if (!success) {
  2229       return;
  2232     print_method(PHASE_GLOBAL_CODE_MOTION, 2);
  2233     NOT_PRODUCT( verify_graph_edges(); )
  2234     debug_only( cfg.verify(); )
  2237   PhaseChaitin regalloc(unique(), cfg, matcher);
  2238   _regalloc = &regalloc;
  2240     TracePhase t2("regalloc", &_t_registerAllocation, true);
  2241     // Perform register allocation.  After Chaitin, use-def chains are
  2242     // no longer accurate (at spill code) and so must be ignored.
  2243     // Node->LRG->reg mappings are still accurate.
  2244     _regalloc->Register_Allocate();
  2246     // Bail out if the allocator builds too many nodes
  2247     if (failing()) {
  2248       return;
  2252   // Prior to register allocation we kept empty basic blocks in case the
  2253   // the allocator needed a place to spill.  After register allocation we
  2254   // are not adding any new instructions.  If any basic block is empty, we
  2255   // can now safely remove it.
  2257     NOT_PRODUCT( TracePhase t2("blockOrdering", &_t_blockOrdering, TimeCompiler); )
  2258     cfg.remove_empty_blocks();
  2259     if (do_freq_based_layout()) {
  2260       PhaseBlockLayout layout(cfg);
  2261     } else {
  2262       cfg.set_loop_alignment();
  2264     cfg.fixup_flow();
  2267   // Apply peephole optimizations
  2268   if( OptoPeephole ) {
  2269     NOT_PRODUCT( TracePhase t2("peephole", &_t_peephole, TimeCompiler); )
  2270     PhasePeephole peep( _regalloc, cfg);
  2271     peep.do_transform();
  2274   // Do late expand if CPU requires this.
  2275   if (Matcher::require_postalloc_expand) {
  2276     NOT_PRODUCT(TracePhase t2c("postalloc_expand", &_t_postalloc_expand, true));
  2277     cfg.postalloc_expand(_regalloc);
  2280   // Convert Nodes to instruction bits in a buffer
  2282     // %%%% workspace merge brought two timers together for one job
  2283     TracePhase t2a("output", &_t_output, true);
  2284     NOT_PRODUCT( TraceTime t2b(NULL, &_t_codeGeneration, TimeCompiler, false); )
  2285     Output();
  2288   print_method(PHASE_FINAL_CODE);
  2290   // He's dead, Jim.
  2291   _cfg     = (PhaseCFG*)0xdeadbeef;
  2292   _regalloc = (PhaseChaitin*)0xdeadbeef;
  2296 //------------------------------dump_asm---------------------------------------
  2297 // Dump formatted assembly
  2298 #ifndef PRODUCT
  2299 void Compile::dump_asm(int *pcs, uint pc_limit) {
  2300   bool cut_short = false;
  2301   tty->print_cr("#");
  2302   tty->print("#  ");  _tf->dump();  tty->cr();
  2303   tty->print_cr("#");
  2305   // For all blocks
  2306   int pc = 0x0;                 // Program counter
  2307   char starts_bundle = ' ';
  2308   _regalloc->dump_frame();
  2310   Node *n = NULL;
  2311   for (uint i = 0; i < _cfg->number_of_blocks(); i++) {
  2312     if (VMThread::should_terminate()) {
  2313       cut_short = true;
  2314       break;
  2316     Block* block = _cfg->get_block(i);
  2317     if (block->is_connector() && !Verbose) {
  2318       continue;
  2320     n = block->head();
  2321     if (pcs && n->_idx < pc_limit) {
  2322       tty->print("%3.3x   ", pcs[n->_idx]);
  2323     } else {
  2324       tty->print("      ");
  2326     block->dump_head(_cfg);
  2327     if (block->is_connector()) {
  2328       tty->print_cr("        # Empty connector block");
  2329     } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
  2330       tty->print_cr("        # Block is sole successor of call");
  2333     // For all instructions
  2334     Node *delay = NULL;
  2335     for (uint j = 0; j < block->number_of_nodes(); j++) {
  2336       if (VMThread::should_terminate()) {
  2337         cut_short = true;
  2338         break;
  2340       n = block->get_node(j);
  2341       if (valid_bundle_info(n)) {
  2342         Bundle* bundle = node_bundling(n);
  2343         if (bundle->used_in_unconditional_delay()) {
  2344           delay = n;
  2345           continue;
  2347         if (bundle->starts_bundle()) {
  2348           starts_bundle = '+';
  2352       if (WizardMode) {
  2353         n->dump();
  2356       if( !n->is_Region() &&    // Dont print in the Assembly
  2357           !n->is_Phi() &&       // a few noisely useless nodes
  2358           !n->is_Proj() &&
  2359           !n->is_MachTemp() &&
  2360           !n->is_SafePointScalarObject() &&
  2361           !n->is_Catch() &&     // Would be nice to print exception table targets
  2362           !n->is_MergeMem() &&  // Not very interesting
  2363           !n->is_top() &&       // Debug info table constants
  2364           !(n->is_Con() && !n->is_Mach())// Debug info table constants
  2365           ) {
  2366         if (pcs && n->_idx < pc_limit)
  2367           tty->print("%3.3x", pcs[n->_idx]);
  2368         else
  2369           tty->print("   ");
  2370         tty->print(" %c ", starts_bundle);
  2371         starts_bundle = ' ';
  2372         tty->print("\t");
  2373         n->format(_regalloc, tty);
  2374         tty->cr();
  2377       // If we have an instruction with a delay slot, and have seen a delay,
  2378       // then back up and print it
  2379       if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
  2380         assert(delay != NULL, "no unconditional delay instruction");
  2381         if (WizardMode) delay->dump();
  2383         if (node_bundling(delay)->starts_bundle())
  2384           starts_bundle = '+';
  2385         if (pcs && n->_idx < pc_limit)
  2386           tty->print("%3.3x", pcs[n->_idx]);
  2387         else
  2388           tty->print("   ");
  2389         tty->print(" %c ", starts_bundle);
  2390         starts_bundle = ' ';
  2391         tty->print("\t");
  2392         delay->format(_regalloc, tty);
  2393         tty->print_cr("");
  2394         delay = NULL;
  2397       // Dump the exception table as well
  2398       if( n->is_Catch() && (Verbose || WizardMode) ) {
  2399         // Print the exception table for this offset
  2400         _handler_table.print_subtable_for(pc);
  2404     if (pcs && n->_idx < pc_limit)
  2405       tty->print_cr("%3.3x", pcs[n->_idx]);
  2406     else
  2407       tty->print_cr("");
  2409     assert(cut_short || delay == NULL, "no unconditional delay branch");
  2411   } // End of per-block dump
  2412   tty->print_cr("");
  2414   if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
  2416 #endif
  2418 //------------------------------Final_Reshape_Counts---------------------------
  2419 // This class defines counters to help identify when a method
  2420 // may/must be executed using hardware with only 24-bit precision.
  2421 struct Final_Reshape_Counts : public StackObj {
  2422   int  _call_count;             // count non-inlined 'common' calls
  2423   int  _float_count;            // count float ops requiring 24-bit precision
  2424   int  _double_count;           // count double ops requiring more precision
  2425   int  _java_call_count;        // count non-inlined 'java' calls
  2426   int  _inner_loop_count;       // count loops which need alignment
  2427   VectorSet _visited;           // Visitation flags
  2428   Node_List _tests;             // Set of IfNodes & PCTableNodes
  2430   Final_Reshape_Counts() :
  2431     _call_count(0), _float_count(0), _double_count(0),
  2432     _java_call_count(0), _inner_loop_count(0),
  2433     _visited( Thread::current()->resource_area() ) { }
  2435   void inc_call_count  () { _call_count  ++; }
  2436   void inc_float_count () { _float_count ++; }
  2437   void inc_double_count() { _double_count++; }
  2438   void inc_java_call_count() { _java_call_count++; }
  2439   void inc_inner_loop_count() { _inner_loop_count++; }
  2441   int  get_call_count  () const { return _call_count  ; }
  2442   int  get_float_count () const { return _float_count ; }
  2443   int  get_double_count() const { return _double_count; }
  2444   int  get_java_call_count() const { return _java_call_count; }
  2445   int  get_inner_loop_count() const { return _inner_loop_count; }
  2446 };
  2448 #ifdef ASSERT
  2449 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
  2450   ciInstanceKlass *k = tp->klass()->as_instance_klass();
  2451   // Make sure the offset goes inside the instance layout.
  2452   return k->contains_field_offset(tp->offset());
  2453   // Note that OffsetBot and OffsetTop are very negative.
  2455 #endif
  2457 // Eliminate trivially redundant StoreCMs and accumulate their
  2458 // precedence edges.
  2459 void Compile::eliminate_redundant_card_marks(Node* n) {
  2460   assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
  2461   if (n->in(MemNode::Address)->outcnt() > 1) {
  2462     // There are multiple users of the same address so it might be
  2463     // possible to eliminate some of the StoreCMs
  2464     Node* mem = n->in(MemNode::Memory);
  2465     Node* adr = n->in(MemNode::Address);
  2466     Node* val = n->in(MemNode::ValueIn);
  2467     Node* prev = n;
  2468     bool done = false;
  2469     // Walk the chain of StoreCMs eliminating ones that match.  As
  2470     // long as it's a chain of single users then the optimization is
  2471     // safe.  Eliminating partially redundant StoreCMs would require
  2472     // cloning copies down the other paths.
  2473     while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
  2474       if (adr == mem->in(MemNode::Address) &&
  2475           val == mem->in(MemNode::ValueIn)) {
  2476         // redundant StoreCM
  2477         if (mem->req() > MemNode::OopStore) {
  2478           // Hasn't been processed by this code yet.
  2479           n->add_prec(mem->in(MemNode::OopStore));
  2480         } else {
  2481           // Already converted to precedence edge
  2482           for (uint i = mem->req(); i < mem->len(); i++) {
  2483             // Accumulate any precedence edges
  2484             if (mem->in(i) != NULL) {
  2485               n->add_prec(mem->in(i));
  2488           // Everything above this point has been processed.
  2489           done = true;
  2491         // Eliminate the previous StoreCM
  2492         prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
  2493         assert(mem->outcnt() == 0, "should be dead");
  2494         mem->disconnect_inputs(NULL, this);
  2495       } else {
  2496         prev = mem;
  2498       mem = prev->in(MemNode::Memory);
  2503 //------------------------------final_graph_reshaping_impl----------------------
  2504 // Implement items 1-5 from final_graph_reshaping below.
  2505 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
  2507   if ( n->outcnt() == 0 ) return; // dead node
  2508   uint nop = n->Opcode();
  2510   // Check for 2-input instruction with "last use" on right input.
  2511   // Swap to left input.  Implements item (2).
  2512   if( n->req() == 3 &&          // two-input instruction
  2513       n->in(1)->outcnt() > 1 && // left use is NOT a last use
  2514       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
  2515       n->in(2)->outcnt() == 1 &&// right use IS a last use
  2516       !n->in(2)->is_Con() ) {   // right use is not a constant
  2517     // Check for commutative opcode
  2518     switch( nop ) {
  2519     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
  2520     case Op_MaxI:  case Op_MinI:
  2521     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
  2522     case Op_AndL:  case Op_XorL:  case Op_OrL:
  2523     case Op_AndI:  case Op_XorI:  case Op_OrI: {
  2524       // Move "last use" input to left by swapping inputs
  2525       n->swap_edges(1, 2);
  2526       break;
  2528     default:
  2529       break;
  2533 #ifdef ASSERT
  2534   if( n->is_Mem() ) {
  2535     int alias_idx = get_alias_index(n->as_Mem()->adr_type());
  2536     assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
  2537             // oop will be recorded in oop map if load crosses safepoint
  2538             n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
  2539                              LoadNode::is_immutable_value(n->in(MemNode::Address))),
  2540             "raw memory operations should have control edge");
  2542 #endif
  2543   // Count FPU ops and common calls, implements item (3)
  2544   switch( nop ) {
  2545   // Count all float operations that may use FPU
  2546   case Op_AddF:
  2547   case Op_SubF:
  2548   case Op_MulF:
  2549   case Op_DivF:
  2550   case Op_NegF:
  2551   case Op_ModF:
  2552   case Op_ConvI2F:
  2553   case Op_ConF:
  2554   case Op_CmpF:
  2555   case Op_CmpF3:
  2556   // case Op_ConvL2F: // longs are split into 32-bit halves
  2557     frc.inc_float_count();
  2558     break;
  2560   case Op_ConvF2D:
  2561   case Op_ConvD2F:
  2562     frc.inc_float_count();
  2563     frc.inc_double_count();
  2564     break;
  2566   // Count all double operations that may use FPU
  2567   case Op_AddD:
  2568   case Op_SubD:
  2569   case Op_MulD:
  2570   case Op_DivD:
  2571   case Op_NegD:
  2572   case Op_ModD:
  2573   case Op_ConvI2D:
  2574   case Op_ConvD2I:
  2575   // case Op_ConvL2D: // handled by leaf call
  2576   // case Op_ConvD2L: // handled by leaf call
  2577   case Op_ConD:
  2578   case Op_CmpD:
  2579   case Op_CmpD3:
  2580     frc.inc_double_count();
  2581     break;
  2582   case Op_Opaque1:              // Remove Opaque Nodes before matching
  2583   case Op_Opaque2:              // Remove Opaque Nodes before matching
  2584     n->subsume_by(n->in(1), this);
  2585     break;
  2586   case Op_CallStaticJava:
  2587   case Op_CallJava:
  2588   case Op_CallDynamicJava:
  2589     frc.inc_java_call_count(); // Count java call site;
  2590   case Op_CallRuntime:
  2591   case Op_CallLeaf:
  2592   case Op_CallLeafNoFP: {
  2593     assert( n->is_Call(), "" );
  2594     CallNode *call = n->as_Call();
  2595     // Count call sites where the FP mode bit would have to be flipped.
  2596     // Do not count uncommon runtime calls:
  2597     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
  2598     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
  2599     if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
  2600       frc.inc_call_count();   // Count the call site
  2601     } else {                  // See if uncommon argument is shared
  2602       Node *n = call->in(TypeFunc::Parms);
  2603       int nop = n->Opcode();
  2604       // Clone shared simple arguments to uncommon calls, item (1).
  2605       if( n->outcnt() > 1 &&
  2606           !n->is_Proj() &&
  2607           nop != Op_CreateEx &&
  2608           nop != Op_CheckCastPP &&
  2609           nop != Op_DecodeN &&
  2610           nop != Op_DecodeNKlass &&
  2611           !n->is_Mem() ) {
  2612         Node *x = n->clone();
  2613         call->set_req( TypeFunc::Parms, x );
  2616     break;
  2619   case Op_StoreD:
  2620   case Op_LoadD:
  2621   case Op_LoadD_unaligned:
  2622     frc.inc_double_count();
  2623     goto handle_mem;
  2624   case Op_StoreF:
  2625   case Op_LoadF:
  2626     frc.inc_float_count();
  2627     goto handle_mem;
  2629   case Op_StoreCM:
  2631       // Convert OopStore dependence into precedence edge
  2632       Node* prec = n->in(MemNode::OopStore);
  2633       n->del_req(MemNode::OopStore);
  2634       n->add_prec(prec);
  2635       eliminate_redundant_card_marks(n);
  2638     // fall through
  2640   case Op_StoreB:
  2641   case Op_StoreC:
  2642   case Op_StorePConditional:
  2643   case Op_StoreI:
  2644   case Op_StoreL:
  2645   case Op_StoreIConditional:
  2646   case Op_StoreLConditional:
  2647   case Op_CompareAndSwapI:
  2648   case Op_CompareAndSwapL:
  2649   case Op_CompareAndSwapP:
  2650   case Op_CompareAndSwapN:
  2651   case Op_GetAndAddI:
  2652   case Op_GetAndAddL:
  2653   case Op_GetAndSetI:
  2654   case Op_GetAndSetL:
  2655   case Op_GetAndSetP:
  2656   case Op_GetAndSetN:
  2657   case Op_StoreP:
  2658   case Op_StoreN:
  2659   case Op_StoreNKlass:
  2660   case Op_LoadB:
  2661   case Op_LoadUB:
  2662   case Op_LoadUS:
  2663   case Op_LoadI:
  2664   case Op_LoadKlass:
  2665   case Op_LoadNKlass:
  2666   case Op_LoadL:
  2667   case Op_LoadL_unaligned:
  2668   case Op_LoadPLocked:
  2669   case Op_LoadP:
  2670   case Op_LoadN:
  2671   case Op_LoadRange:
  2672   case Op_LoadS: {
  2673   handle_mem:
  2674 #ifdef ASSERT
  2675     if( VerifyOptoOopOffsets ) {
  2676       assert( n->is_Mem(), "" );
  2677       MemNode *mem  = (MemNode*)n;
  2678       // Check to see if address types have grounded out somehow.
  2679       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
  2680       assert( !tp || oop_offset_is_sane(tp), "" );
  2682 #endif
  2683     break;
  2686   case Op_AddP: {               // Assert sane base pointers
  2687     Node *addp = n->in(AddPNode::Address);
  2688     assert( !addp->is_AddP() ||
  2689             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
  2690             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
  2691             "Base pointers must match" );
  2692 #ifdef _LP64
  2693     if ((UseCompressedOops || UseCompressedClassPointers) &&
  2694         addp->Opcode() == Op_ConP &&
  2695         addp == n->in(AddPNode::Base) &&
  2696         n->in(AddPNode::Offset)->is_Con()) {
  2697       // Use addressing with narrow klass to load with offset on x86.
  2698       // On sparc loading 32-bits constant and decoding it have less
  2699       // instructions (4) then load 64-bits constant (7).
  2700       // Do this transformation here since IGVN will convert ConN back to ConP.
  2701       const Type* t = addp->bottom_type();
  2702       if (t->isa_oopptr() || t->isa_klassptr()) {
  2703         Node* nn = NULL;
  2705         int op = t->isa_oopptr() ? Op_ConN : Op_ConNKlass;
  2707         // Look for existing ConN node of the same exact type.
  2708         Node* r  = root();
  2709         uint cnt = r->outcnt();
  2710         for (uint i = 0; i < cnt; i++) {
  2711           Node* m = r->raw_out(i);
  2712           if (m!= NULL && m->Opcode() == op &&
  2713               m->bottom_type()->make_ptr() == t) {
  2714             nn = m;
  2715             break;
  2718         if (nn != NULL) {
  2719           // Decode a narrow oop to match address
  2720           // [R12 + narrow_oop_reg<<3 + offset]
  2721           if (t->isa_oopptr()) {
  2722             nn = new (this) DecodeNNode(nn, t);
  2723           } else {
  2724             nn = new (this) DecodeNKlassNode(nn, t);
  2726           n->set_req(AddPNode::Base, nn);
  2727           n->set_req(AddPNode::Address, nn);
  2728           if (addp->outcnt() == 0) {
  2729             addp->disconnect_inputs(NULL, this);
  2734 #endif
  2735     break;
  2738 #ifdef _LP64
  2739   case Op_CastPP:
  2740     if (n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
  2741       Node* in1 = n->in(1);
  2742       const Type* t = n->bottom_type();
  2743       Node* new_in1 = in1->clone();
  2744       new_in1->as_DecodeN()->set_type(t);
  2746       if (!Matcher::narrow_oop_use_complex_address()) {
  2747         //
  2748         // x86, ARM and friends can handle 2 adds in addressing mode
  2749         // and Matcher can fold a DecodeN node into address by using
  2750         // a narrow oop directly and do implicit NULL check in address:
  2751         //
  2752         // [R12 + narrow_oop_reg<<3 + offset]
  2753         // NullCheck narrow_oop_reg
  2754         //
  2755         // On other platforms (Sparc) we have to keep new DecodeN node and
  2756         // use it to do implicit NULL check in address:
  2757         //
  2758         // decode_not_null narrow_oop_reg, base_reg
  2759         // [base_reg + offset]
  2760         // NullCheck base_reg
  2761         //
  2762         // Pin the new DecodeN node to non-null path on these platform (Sparc)
  2763         // to keep the information to which NULL check the new DecodeN node
  2764         // corresponds to use it as value in implicit_null_check().
  2765         //
  2766         new_in1->set_req(0, n->in(0));
  2769       n->subsume_by(new_in1, this);
  2770       if (in1->outcnt() == 0) {
  2771         in1->disconnect_inputs(NULL, this);
  2774     break;
  2776   case Op_CmpP:
  2777     // Do this transformation here to preserve CmpPNode::sub() and
  2778     // other TypePtr related Ideal optimizations (for example, ptr nullness).
  2779     if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
  2780       Node* in1 = n->in(1);
  2781       Node* in2 = n->in(2);
  2782       if (!in1->is_DecodeNarrowPtr()) {
  2783         in2 = in1;
  2784         in1 = n->in(2);
  2786       assert(in1->is_DecodeNarrowPtr(), "sanity");
  2788       Node* new_in2 = NULL;
  2789       if (in2->is_DecodeNarrowPtr()) {
  2790         assert(in2->Opcode() == in1->Opcode(), "must be same node type");
  2791         new_in2 = in2->in(1);
  2792       } else if (in2->Opcode() == Op_ConP) {
  2793         const Type* t = in2->bottom_type();
  2794         if (t == TypePtr::NULL_PTR) {
  2795           assert(in1->is_DecodeN(), "compare klass to null?");
  2796           // Don't convert CmpP null check into CmpN if compressed
  2797           // oops implicit null check is not generated.
  2798           // This will allow to generate normal oop implicit null check.
  2799           if (Matcher::gen_narrow_oop_implicit_null_checks())
  2800             new_in2 = ConNode::make(this, TypeNarrowOop::NULL_PTR);
  2801           //
  2802           // This transformation together with CastPP transformation above
  2803           // will generated code for implicit NULL checks for compressed oops.
  2804           //
  2805           // The original code after Optimize()
  2806           //
  2807           //    LoadN memory, narrow_oop_reg
  2808           //    decode narrow_oop_reg, base_reg
  2809           //    CmpP base_reg, NULL
  2810           //    CastPP base_reg // NotNull
  2811           //    Load [base_reg + offset], val_reg
  2812           //
  2813           // after these transformations will be
  2814           //
  2815           //    LoadN memory, narrow_oop_reg
  2816           //    CmpN narrow_oop_reg, NULL
  2817           //    decode_not_null narrow_oop_reg, base_reg
  2818           //    Load [base_reg + offset], val_reg
  2819           //
  2820           // and the uncommon path (== NULL) will use narrow_oop_reg directly
  2821           // since narrow oops can be used in debug info now (see the code in
  2822           // final_graph_reshaping_walk()).
  2823           //
  2824           // At the end the code will be matched to
  2825           // on x86:
  2826           //
  2827           //    Load_narrow_oop memory, narrow_oop_reg
  2828           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
  2829           //    NullCheck narrow_oop_reg
  2830           //
  2831           // and on sparc:
  2832           //
  2833           //    Load_narrow_oop memory, narrow_oop_reg
  2834           //    decode_not_null narrow_oop_reg, base_reg
  2835           //    Load [base_reg + offset], val_reg
  2836           //    NullCheck base_reg
  2837           //
  2838         } else if (t->isa_oopptr()) {
  2839           new_in2 = ConNode::make(this, t->make_narrowoop());
  2840         } else if (t->isa_klassptr()) {
  2841           new_in2 = ConNode::make(this, t->make_narrowklass());
  2844       if (new_in2 != NULL) {
  2845         Node* cmpN = new (this) CmpNNode(in1->in(1), new_in2);
  2846         n->subsume_by(cmpN, this);
  2847         if (in1->outcnt() == 0) {
  2848           in1->disconnect_inputs(NULL, this);
  2850         if (in2->outcnt() == 0) {
  2851           in2->disconnect_inputs(NULL, this);
  2855     break;
  2857   case Op_DecodeN:
  2858   case Op_DecodeNKlass:
  2859     assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
  2860     // DecodeN could be pinned when it can't be fold into
  2861     // an address expression, see the code for Op_CastPP above.
  2862     assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
  2863     break;
  2865   case Op_EncodeP:
  2866   case Op_EncodePKlass: {
  2867     Node* in1 = n->in(1);
  2868     if (in1->is_DecodeNarrowPtr()) {
  2869       n->subsume_by(in1->in(1), this);
  2870     } else if (in1->Opcode() == Op_ConP) {
  2871       const Type* t = in1->bottom_type();
  2872       if (t == TypePtr::NULL_PTR) {
  2873         assert(t->isa_oopptr(), "null klass?");
  2874         n->subsume_by(ConNode::make(this, TypeNarrowOop::NULL_PTR), this);
  2875       } else if (t->isa_oopptr()) {
  2876         n->subsume_by(ConNode::make(this, t->make_narrowoop()), this);
  2877       } else if (t->isa_klassptr()) {
  2878         n->subsume_by(ConNode::make(this, t->make_narrowklass()), this);
  2881     if (in1->outcnt() == 0) {
  2882       in1->disconnect_inputs(NULL, this);
  2884     break;
  2887   case Op_Proj: {
  2888     if (OptimizeStringConcat) {
  2889       ProjNode* p = n->as_Proj();
  2890       if (p->_is_io_use) {
  2891         // Separate projections were used for the exception path which
  2892         // are normally removed by a late inline.  If it wasn't inlined
  2893         // then they will hang around and should just be replaced with
  2894         // the original one.
  2895         Node* proj = NULL;
  2896         // Replace with just one
  2897         for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
  2898           Node *use = i.get();
  2899           if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
  2900             proj = use;
  2901             break;
  2904         assert(proj != NULL, "must be found");
  2905         p->subsume_by(proj, this);
  2908     break;
  2911   case Op_Phi:
  2912     if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
  2913       // The EncodeP optimization may create Phi with the same edges
  2914       // for all paths. It is not handled well by Register Allocator.
  2915       Node* unique_in = n->in(1);
  2916       assert(unique_in != NULL, "");
  2917       uint cnt = n->req();
  2918       for (uint i = 2; i < cnt; i++) {
  2919         Node* m = n->in(i);
  2920         assert(m != NULL, "");
  2921         if (unique_in != m)
  2922           unique_in = NULL;
  2924       if (unique_in != NULL) {
  2925         n->subsume_by(unique_in, this);
  2928     break;
  2930 #endif
  2932   case Op_ModI:
  2933     if (UseDivMod) {
  2934       // Check if a%b and a/b both exist
  2935       Node* d = n->find_similar(Op_DivI);
  2936       if (d) {
  2937         // Replace them with a fused divmod if supported
  2938         if (Matcher::has_match_rule(Op_DivModI)) {
  2939           DivModINode* divmod = DivModINode::make(this, n);
  2940           d->subsume_by(divmod->div_proj(), this);
  2941           n->subsume_by(divmod->mod_proj(), this);
  2942         } else {
  2943           // replace a%b with a-((a/b)*b)
  2944           Node* mult = new (this) MulINode(d, d->in(2));
  2945           Node* sub  = new (this) SubINode(d->in(1), mult);
  2946           n->subsume_by(sub, this);
  2950     break;
  2952   case Op_ModL:
  2953     if (UseDivMod) {
  2954       // Check if a%b and a/b both exist
  2955       Node* d = n->find_similar(Op_DivL);
  2956       if (d) {
  2957         // Replace them with a fused divmod if supported
  2958         if (Matcher::has_match_rule(Op_DivModL)) {
  2959           DivModLNode* divmod = DivModLNode::make(this, n);
  2960           d->subsume_by(divmod->div_proj(), this);
  2961           n->subsume_by(divmod->mod_proj(), this);
  2962         } else {
  2963           // replace a%b with a-((a/b)*b)
  2964           Node* mult = new (this) MulLNode(d, d->in(2));
  2965           Node* sub  = new (this) SubLNode(d->in(1), mult);
  2966           n->subsume_by(sub, this);
  2970     break;
  2972   case Op_LoadVector:
  2973   case Op_StoreVector:
  2974     break;
  2976   case Op_PackB:
  2977   case Op_PackS:
  2978   case Op_PackI:
  2979   case Op_PackF:
  2980   case Op_PackL:
  2981   case Op_PackD:
  2982     if (n->req()-1 > 2) {
  2983       // Replace many operand PackNodes with a binary tree for matching
  2984       PackNode* p = (PackNode*) n;
  2985       Node* btp = p->binary_tree_pack(this, 1, n->req());
  2986       n->subsume_by(btp, this);
  2988     break;
  2989   case Op_Loop:
  2990   case Op_CountedLoop:
  2991     if (n->as_Loop()->is_inner_loop()) {
  2992       frc.inc_inner_loop_count();
  2994     break;
  2995   case Op_LShiftI:
  2996   case Op_RShiftI:
  2997   case Op_URShiftI:
  2998   case Op_LShiftL:
  2999   case Op_RShiftL:
  3000   case Op_URShiftL:
  3001     if (Matcher::need_masked_shift_count) {
  3002       // The cpu's shift instructions don't restrict the count to the
  3003       // lower 5/6 bits. We need to do the masking ourselves.
  3004       Node* in2 = n->in(2);
  3005       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
  3006       const TypeInt* t = in2->find_int_type();
  3007       if (t != NULL && t->is_con()) {
  3008         juint shift = t->get_con();
  3009         if (shift > mask) { // Unsigned cmp
  3010           n->set_req(2, ConNode::make(this, TypeInt::make(shift & mask)));
  3012       } else {
  3013         if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
  3014           Node* shift = new (this) AndINode(in2, ConNode::make(this, TypeInt::make(mask)));
  3015           n->set_req(2, shift);
  3018       if (in2->outcnt() == 0) { // Remove dead node
  3019         in2->disconnect_inputs(NULL, this);
  3022     break;
  3023   case Op_MemBarStoreStore:
  3024   case Op_MemBarRelease:
  3025     // Break the link with AllocateNode: it is no longer useful and
  3026     // confuses register allocation.
  3027     if (n->req() > MemBarNode::Precedent) {
  3028       n->set_req(MemBarNode::Precedent, top());
  3030     break;
  3031     // Must set a control edge on all nodes that produce a FlagsProj
  3032     // so they can't escape the block that consumes the flags.
  3033     // Must also set the non throwing branch as the control
  3034     // for all nodes that depends on the result. Unless the node
  3035     // already have a control that isn't the control of the
  3036     // flag producer
  3037   case Op_FlagsProj:
  3039       MathExactNode* math = (MathExactNode*)  n->in(0);
  3040       Node* ctrl = math->control_node();
  3041       Node* non_throwing = math->non_throwing_branch();
  3042       math->set_req(0, ctrl);
  3044       Node* result = math->result_node();
  3045       if (result != NULL) {
  3046         for (DUIterator_Fast jmax, j = result->fast_outs(jmax); j < jmax; j++) {
  3047           Node* out = result->fast_out(j);
  3048           // Phi nodes shouldn't be moved. They would only match below if they
  3049           // had the same control as the MathExactNode. The only time that
  3050           // would happen is if the Phi is also an input to the MathExact
  3051           //
  3052           // Cmp nodes shouldn't have control set at all.
  3053           if (out->is_Phi() ||
  3054               out->is_Cmp()) {
  3055             continue;
  3058           if (out->in(0) == NULL) {
  3059             out->set_req(0, non_throwing);
  3060           } else if (out->in(0) == ctrl) {
  3061             out->set_req(0, non_throwing);
  3066     break;
  3067   default:
  3068     assert( !n->is_Call(), "" );
  3069     assert( !n->is_Mem(), "" );
  3070     break;
  3073   // Collect CFG split points
  3074   if (n->is_MultiBranch())
  3075     frc._tests.push(n);
  3078 //------------------------------final_graph_reshaping_walk---------------------
  3079 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
  3080 // requires that the walk visits a node's inputs before visiting the node.
  3081 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
  3082   ResourceArea *area = Thread::current()->resource_area();
  3083   Unique_Node_List sfpt(area);
  3085   frc._visited.set(root->_idx); // first, mark node as visited
  3086   uint cnt = root->req();
  3087   Node *n = root;
  3088   uint  i = 0;
  3089   while (true) {
  3090     if (i < cnt) {
  3091       // Place all non-visited non-null inputs onto stack
  3092       Node* m = n->in(i);
  3093       ++i;
  3094       if (m != NULL && !frc._visited.test_set(m->_idx)) {
  3095         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL)
  3096           sfpt.push(m);
  3097         cnt = m->req();
  3098         nstack.push(n, i); // put on stack parent and next input's index
  3099         n = m;
  3100         i = 0;
  3102     } else {
  3103       // Now do post-visit work
  3104       final_graph_reshaping_impl( n, frc );
  3105       if (nstack.is_empty())
  3106         break;             // finished
  3107       n = nstack.node();   // Get node from stack
  3108       cnt = n->req();
  3109       i = nstack.index();
  3110       nstack.pop();        // Shift to the next node on stack
  3114   // Skip next transformation if compressed oops are not used.
  3115   if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
  3116       (!UseCompressedOops && !UseCompressedClassPointers))
  3117     return;
  3119   // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
  3120   // It could be done for an uncommon traps or any safepoints/calls
  3121   // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
  3122   while (sfpt.size() > 0) {
  3123     n = sfpt.pop();
  3124     JVMState *jvms = n->as_SafePoint()->jvms();
  3125     assert(jvms != NULL, "sanity");
  3126     int start = jvms->debug_start();
  3127     int end   = n->req();
  3128     bool is_uncommon = (n->is_CallStaticJava() &&
  3129                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
  3130     for (int j = start; j < end; j++) {
  3131       Node* in = n->in(j);
  3132       if (in->is_DecodeNarrowPtr()) {
  3133         bool safe_to_skip = true;
  3134         if (!is_uncommon ) {
  3135           // Is it safe to skip?
  3136           for (uint i = 0; i < in->outcnt(); i++) {
  3137             Node* u = in->raw_out(i);
  3138             if (!u->is_SafePoint() ||
  3139                  u->is_Call() && u->as_Call()->has_non_debug_use(n)) {
  3140               safe_to_skip = false;
  3144         if (safe_to_skip) {
  3145           n->set_req(j, in->in(1));
  3147         if (in->outcnt() == 0) {
  3148           in->disconnect_inputs(NULL, this);
  3155 //------------------------------final_graph_reshaping--------------------------
  3156 // Final Graph Reshaping.
  3157 //
  3158 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
  3159 //     and not commoned up and forced early.  Must come after regular
  3160 //     optimizations to avoid GVN undoing the cloning.  Clone constant
  3161 //     inputs to Loop Phis; these will be split by the allocator anyways.
  3162 //     Remove Opaque nodes.
  3163 // (2) Move last-uses by commutative operations to the left input to encourage
  3164 //     Intel update-in-place two-address operations and better register usage
  3165 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
  3166 //     calls canonicalizing them back.
  3167 // (3) Count the number of double-precision FP ops, single-precision FP ops
  3168 //     and call sites.  On Intel, we can get correct rounding either by
  3169 //     forcing singles to memory (requires extra stores and loads after each
  3170 //     FP bytecode) or we can set a rounding mode bit (requires setting and
  3171 //     clearing the mode bit around call sites).  The mode bit is only used
  3172 //     if the relative frequency of single FP ops to calls is low enough.
  3173 //     This is a key transform for SPEC mpeg_audio.
  3174 // (4) Detect infinite loops; blobs of code reachable from above but not
  3175 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
  3176 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
  3177 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
  3178 //     Detection is by looking for IfNodes where only 1 projection is
  3179 //     reachable from below or CatchNodes missing some targets.
  3180 // (5) Assert for insane oop offsets in debug mode.
  3182 bool Compile::final_graph_reshaping() {
  3183   // an infinite loop may have been eliminated by the optimizer,
  3184   // in which case the graph will be empty.
  3185   if (root()->req() == 1) {
  3186     record_method_not_compilable("trivial infinite loop");
  3187     return true;
  3190   // Expensive nodes have their control input set to prevent the GVN
  3191   // from freely commoning them. There's no GVN beyond this point so
  3192   // no need to keep the control input. We want the expensive nodes to
  3193   // be freely moved to the least frequent code path by gcm.
  3194   assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
  3195   for (int i = 0; i < expensive_count(); i++) {
  3196     _expensive_nodes->at(i)->set_req(0, NULL);
  3199   Final_Reshape_Counts frc;
  3201   // Visit everybody reachable!
  3202   // Allocate stack of size C->unique()/2 to avoid frequent realloc
  3203   Node_Stack nstack(unique() >> 1);
  3204   final_graph_reshaping_walk(nstack, root(), frc);
  3206   // Check for unreachable (from below) code (i.e., infinite loops).
  3207   for( uint i = 0; i < frc._tests.size(); i++ ) {
  3208     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
  3209     // Get number of CFG targets.
  3210     // Note that PCTables include exception targets after calls.
  3211     uint required_outcnt = n->required_outcnt();
  3212     if (n->outcnt() != required_outcnt) {
  3213       // Check for a few special cases.  Rethrow Nodes never take the
  3214       // 'fall-thru' path, so expected kids is 1 less.
  3215       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
  3216         if (n->in(0)->in(0)->is_Call()) {
  3217           CallNode *call = n->in(0)->in(0)->as_Call();
  3218           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
  3219             required_outcnt--;      // Rethrow always has 1 less kid
  3220           } else if (call->req() > TypeFunc::Parms &&
  3221                      call->is_CallDynamicJava()) {
  3222             // Check for null receiver. In such case, the optimizer has
  3223             // detected that the virtual call will always result in a null
  3224             // pointer exception. The fall-through projection of this CatchNode
  3225             // will not be populated.
  3226             Node *arg0 = call->in(TypeFunc::Parms);
  3227             if (arg0->is_Type() &&
  3228                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
  3229               required_outcnt--;
  3231           } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
  3232                      call->req() > TypeFunc::Parms+1 &&
  3233                      call->is_CallStaticJava()) {
  3234             // Check for negative array length. In such case, the optimizer has
  3235             // detected that the allocation attempt will always result in an
  3236             // exception. There is no fall-through projection of this CatchNode .
  3237             Node *arg1 = call->in(TypeFunc::Parms+1);
  3238             if (arg1->is_Type() &&
  3239                 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
  3240               required_outcnt--;
  3245       // Recheck with a better notion of 'required_outcnt'
  3246       if (n->outcnt() != required_outcnt) {
  3247         record_method_not_compilable("malformed control flow");
  3248         return true;            // Not all targets reachable!
  3251     // Check that I actually visited all kids.  Unreached kids
  3252     // must be infinite loops.
  3253     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
  3254       if (!frc._visited.test(n->fast_out(j)->_idx)) {
  3255         record_method_not_compilable("infinite loop");
  3256         return true;            // Found unvisited kid; must be unreach
  3260   // If original bytecodes contained a mixture of floats and doubles
  3261   // check if the optimizer has made it homogenous, item (3).
  3262   if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
  3263       frc.get_float_count() > 32 &&
  3264       frc.get_double_count() == 0 &&
  3265       (10 * frc.get_call_count() < frc.get_float_count()) ) {
  3266     set_24_bit_selection_and_mode( false,  true );
  3269   set_java_calls(frc.get_java_call_count());
  3270   set_inner_loops(frc.get_inner_loop_count());
  3272   // No infinite loops, no reason to bail out.
  3273   return false;
  3276 //-----------------------------too_many_traps----------------------------------
  3277 // Report if there are too many traps at the current method and bci.
  3278 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
  3279 bool Compile::too_many_traps(ciMethod* method,
  3280                              int bci,
  3281                              Deoptimization::DeoptReason reason) {
  3282   ciMethodData* md = method->method_data();
  3283   if (md->is_empty()) {
  3284     // Assume the trap has not occurred, or that it occurred only
  3285     // because of a transient condition during start-up in the interpreter.
  3286     return false;
  3288   if (md->has_trap_at(bci, reason) != 0) {
  3289     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
  3290     // Also, if there are multiple reasons, or if there is no per-BCI record,
  3291     // assume the worst.
  3292     if (log())
  3293       log()->elem("observe trap='%s' count='%d'",
  3294                   Deoptimization::trap_reason_name(reason),
  3295                   md->trap_count(reason));
  3296     return true;
  3297   } else {
  3298     // Ignore method/bci and see if there have been too many globally.
  3299     return too_many_traps(reason, md);
  3303 // Less-accurate variant which does not require a method and bci.
  3304 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
  3305                              ciMethodData* logmd) {
  3306  if (trap_count(reason) >= (uint)PerMethodTrapLimit) {
  3307     // Too many traps globally.
  3308     // Note that we use cumulative trap_count, not just md->trap_count.
  3309     if (log()) {
  3310       int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
  3311       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
  3312                   Deoptimization::trap_reason_name(reason),
  3313                   mcount, trap_count(reason));
  3315     return true;
  3316   } else {
  3317     // The coast is clear.
  3318     return false;
  3322 //--------------------------too_many_recompiles--------------------------------
  3323 // Report if there are too many recompiles at the current method and bci.
  3324 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
  3325 // Is not eager to return true, since this will cause the compiler to use
  3326 // Action_none for a trap point, to avoid too many recompilations.
  3327 bool Compile::too_many_recompiles(ciMethod* method,
  3328                                   int bci,
  3329                                   Deoptimization::DeoptReason reason) {
  3330   ciMethodData* md = method->method_data();
  3331   if (md->is_empty()) {
  3332     // Assume the trap has not occurred, or that it occurred only
  3333     // because of a transient condition during start-up in the interpreter.
  3334     return false;
  3336   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
  3337   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
  3338   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
  3339   Deoptimization::DeoptReason per_bc_reason
  3340     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
  3341   if ((per_bc_reason == Deoptimization::Reason_none
  3342        || md->has_trap_at(bci, reason) != 0)
  3343       // The trap frequency measure we care about is the recompile count:
  3344       && md->trap_recompiled_at(bci)
  3345       && md->overflow_recompile_count() >= bc_cutoff) {
  3346     // Do not emit a trap here if it has already caused recompilations.
  3347     // Also, if there are multiple reasons, or if there is no per-BCI record,
  3348     // assume the worst.
  3349     if (log())
  3350       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
  3351                   Deoptimization::trap_reason_name(reason),
  3352                   md->trap_count(reason),
  3353                   md->overflow_recompile_count());
  3354     return true;
  3355   } else if (trap_count(reason) != 0
  3356              && decompile_count() >= m_cutoff) {
  3357     // Too many recompiles globally, and we have seen this sort of trap.
  3358     // Use cumulative decompile_count, not just md->decompile_count.
  3359     if (log())
  3360       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
  3361                   Deoptimization::trap_reason_name(reason),
  3362                   md->trap_count(reason), trap_count(reason),
  3363                   md->decompile_count(), decompile_count());
  3364     return true;
  3365   } else {
  3366     // The coast is clear.
  3367     return false;
  3371 // Compute when not to trap. Used by matching trap based nodes and
  3372 // NullCheck optimization.
  3373 void Compile::set_allowed_deopt_reasons() {
  3374   _allowed_reasons = 0;
  3375   if (is_method_compilation()) {
  3376     for (int rs = (int)Deoptimization::Reason_none+1; rs < Compile::trapHistLength; rs++) {
  3377       assert(rs < BitsPerInt, "recode bit map");
  3378       if (!too_many_traps((Deoptimization::DeoptReason) rs)) {
  3379         _allowed_reasons |= nth_bit(rs);
  3385 #ifndef PRODUCT
  3386 //------------------------------verify_graph_edges---------------------------
  3387 // Walk the Graph and verify that there is a one-to-one correspondence
  3388 // between Use-Def edges and Def-Use edges in the graph.
  3389 void Compile::verify_graph_edges(bool no_dead_code) {
  3390   if (VerifyGraphEdges) {
  3391     ResourceArea *area = Thread::current()->resource_area();
  3392     Unique_Node_List visited(area);
  3393     // Call recursive graph walk to check edges
  3394     _root->verify_edges(visited);
  3395     if (no_dead_code) {
  3396       // Now make sure that no visited node is used by an unvisited node.
  3397       bool dead_nodes = 0;
  3398       Unique_Node_List checked(area);
  3399       while (visited.size() > 0) {
  3400         Node* n = visited.pop();
  3401         checked.push(n);
  3402         for (uint i = 0; i < n->outcnt(); i++) {
  3403           Node* use = n->raw_out(i);
  3404           if (checked.member(use))  continue;  // already checked
  3405           if (visited.member(use))  continue;  // already in the graph
  3406           if (use->is_Con())        continue;  // a dead ConNode is OK
  3407           // At this point, we have found a dead node which is DU-reachable.
  3408           if (dead_nodes++ == 0)
  3409             tty->print_cr("*** Dead nodes reachable via DU edges:");
  3410           use->dump(2);
  3411           tty->print_cr("---");
  3412           checked.push(use);  // No repeats; pretend it is now checked.
  3415       assert(dead_nodes == 0, "using nodes must be reachable from root");
  3420 // Verify GC barriers consistency
  3421 // Currently supported:
  3422 // - G1 pre-barriers (see GraphKit::g1_write_barrier_pre())
  3423 void Compile::verify_barriers() {
  3424   if (UseG1GC) {
  3425     // Verify G1 pre-barriers
  3426     const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + PtrQueue::byte_offset_of_active());
  3428     ResourceArea *area = Thread::current()->resource_area();
  3429     Unique_Node_List visited(area);
  3430     Node_List worklist(area);
  3431     // We're going to walk control flow backwards starting from the Root
  3432     worklist.push(_root);
  3433     while (worklist.size() > 0) {
  3434       Node* x = worklist.pop();
  3435       if (x == NULL || x == top()) continue;
  3436       if (visited.member(x)) {
  3437         continue;
  3438       } else {
  3439         visited.push(x);
  3442       if (x->is_Region()) {
  3443         for (uint i = 1; i < x->req(); i++) {
  3444           worklist.push(x->in(i));
  3446       } else {
  3447         worklist.push(x->in(0));
  3448         // We are looking for the pattern:
  3449         //                            /->ThreadLocal
  3450         // If->Bool->CmpI->LoadB->AddP->ConL(marking_offset)
  3451         //              \->ConI(0)
  3452         // We want to verify that the If and the LoadB have the same control
  3453         // See GraphKit::g1_write_barrier_pre()
  3454         if (x->is_If()) {
  3455           IfNode *iff = x->as_If();
  3456           if (iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) {
  3457             CmpNode *cmp = iff->in(1)->in(1)->as_Cmp();
  3458             if (cmp->Opcode() == Op_CmpI && cmp->in(2)->is_Con() && cmp->in(2)->bottom_type()->is_int()->get_con() == 0
  3459                 && cmp->in(1)->is_Load()) {
  3460               LoadNode* load = cmp->in(1)->as_Load();
  3461               if (load->Opcode() == Op_LoadB && load->in(2)->is_AddP() && load->in(2)->in(2)->Opcode() == Op_ThreadLocal
  3462                   && load->in(2)->in(3)->is_Con()
  3463                   && load->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == marking_offset) {
  3465                 Node* if_ctrl = iff->in(0);
  3466                 Node* load_ctrl = load->in(0);
  3468                 if (if_ctrl != load_ctrl) {
  3469                   // Skip possible CProj->NeverBranch in infinite loops
  3470                   if ((if_ctrl->is_Proj() && if_ctrl->Opcode() == Op_CProj)
  3471                       && (if_ctrl->in(0)->is_MultiBranch() && if_ctrl->in(0)->Opcode() == Op_NeverBranch)) {
  3472                     if_ctrl = if_ctrl->in(0)->in(0);
  3475                 assert(load_ctrl != NULL && if_ctrl == load_ctrl, "controls must match");
  3485 #endif
  3487 // The Compile object keeps track of failure reasons separately from the ciEnv.
  3488 // This is required because there is not quite a 1-1 relation between the
  3489 // ciEnv and its compilation task and the Compile object.  Note that one
  3490 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
  3491 // to backtrack and retry without subsuming loads.  Other than this backtracking
  3492 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
  3493 // by the logic in C2Compiler.
  3494 void Compile::record_failure(const char* reason) {
  3495   if (log() != NULL) {
  3496     log()->elem("failure reason='%s' phase='compile'", reason);
  3498   if (_failure_reason == NULL) {
  3499     // Record the first failure reason.
  3500     _failure_reason = reason;
  3503   EventCompilerFailure event;
  3504   if (event.should_commit()) {
  3505     event.set_compileID(Compile::compile_id());
  3506     event.set_failure(reason);
  3507     event.commit();
  3510   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
  3511     C->print_method(PHASE_FAILURE);
  3513   _root = NULL;  // flush the graph, too
  3516 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator, bool dolog)
  3517   : TraceTime(NULL, accumulator, false NOT_PRODUCT( || TimeCompiler ), false),
  3518     _phase_name(name), _dolog(dolog)
  3520   if (dolog) {
  3521     C = Compile::current();
  3522     _log = C->log();
  3523   } else {
  3524     C = NULL;
  3525     _log = NULL;
  3527   if (_log != NULL) {
  3528     _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
  3529     _log->stamp();
  3530     _log->end_head();
  3534 Compile::TracePhase::~TracePhase() {
  3536   C = Compile::current();
  3537   if (_dolog) {
  3538     _log = C->log();
  3539   } else {
  3540     _log = NULL;
  3543 #ifdef ASSERT
  3544   if (PrintIdealNodeCount) {
  3545     tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
  3546                   _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
  3549   if (VerifyIdealNodeCount) {
  3550     Compile::current()->print_missing_nodes();
  3552 #endif
  3554   if (_log != NULL) {
  3555     _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
  3559 //=============================================================================
  3560 // Two Constant's are equal when the type and the value are equal.
  3561 bool Compile::Constant::operator==(const Constant& other) {
  3562   if (type()          != other.type()         )  return false;
  3563   if (can_be_reused() != other.can_be_reused())  return false;
  3564   // For floating point values we compare the bit pattern.
  3565   switch (type()) {
  3566   case T_FLOAT:   return (_v._value.i == other._v._value.i);
  3567   case T_LONG:
  3568   case T_DOUBLE:  return (_v._value.j == other._v._value.j);
  3569   case T_OBJECT:
  3570   case T_ADDRESS: return (_v._value.l == other._v._value.l);
  3571   case T_VOID:    return (_v._value.l == other._v._value.l);  // jump-table entries
  3572   case T_METADATA: return (_v._metadata == other._v._metadata);
  3573   default: ShouldNotReachHere();
  3575   return false;
  3578 static int type_to_size_in_bytes(BasicType t) {
  3579   switch (t) {
  3580   case T_LONG:    return sizeof(jlong  );
  3581   case T_FLOAT:   return sizeof(jfloat );
  3582   case T_DOUBLE:  return sizeof(jdouble);
  3583   case T_METADATA: return sizeof(Metadata*);
  3584     // We use T_VOID as marker for jump-table entries (labels) which
  3585     // need an internal word relocation.
  3586   case T_VOID:
  3587   case T_ADDRESS:
  3588   case T_OBJECT:  return sizeof(jobject);
  3591   ShouldNotReachHere();
  3592   return -1;
  3595 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
  3596   // sort descending
  3597   if (a->freq() > b->freq())  return -1;
  3598   if (a->freq() < b->freq())  return  1;
  3599   return 0;
  3602 void Compile::ConstantTable::calculate_offsets_and_size() {
  3603   // First, sort the array by frequencies.
  3604   _constants.sort(qsort_comparator);
  3606 #ifdef ASSERT
  3607   // Make sure all jump-table entries were sorted to the end of the
  3608   // array (they have a negative frequency).
  3609   bool found_void = false;
  3610   for (int i = 0; i < _constants.length(); i++) {
  3611     Constant con = _constants.at(i);
  3612     if (con.type() == T_VOID)
  3613       found_void = true;  // jump-tables
  3614     else
  3615       assert(!found_void, "wrong sorting");
  3617 #endif
  3619   int offset = 0;
  3620   for (int i = 0; i < _constants.length(); i++) {
  3621     Constant* con = _constants.adr_at(i);
  3623     // Align offset for type.
  3624     int typesize = type_to_size_in_bytes(con->type());
  3625     offset = align_size_up(offset, typesize);
  3626     con->set_offset(offset);   // set constant's offset
  3628     if (con->type() == T_VOID) {
  3629       MachConstantNode* n = (MachConstantNode*) con->get_jobject();
  3630       offset = offset + typesize * n->outcnt();  // expand jump-table
  3631     } else {
  3632       offset = offset + typesize;
  3636   // Align size up to the next section start (which is insts; see
  3637   // CodeBuffer::align_at_start).
  3638   assert(_size == -1, "already set?");
  3639   _size = align_size_up(offset, CodeEntryAlignment);
  3642 void Compile::ConstantTable::emit(CodeBuffer& cb) {
  3643   MacroAssembler _masm(&cb);
  3644   for (int i = 0; i < _constants.length(); i++) {
  3645     Constant con = _constants.at(i);
  3646     address constant_addr;
  3647     switch (con.type()) {
  3648     case T_LONG:   constant_addr = _masm.long_constant(  con.get_jlong()  ); break;
  3649     case T_FLOAT:  constant_addr = _masm.float_constant( con.get_jfloat() ); break;
  3650     case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
  3651     case T_OBJECT: {
  3652       jobject obj = con.get_jobject();
  3653       int oop_index = _masm.oop_recorder()->find_index(obj);
  3654       constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
  3655       break;
  3657     case T_ADDRESS: {
  3658       address addr = (address) con.get_jobject();
  3659       constant_addr = _masm.address_constant(addr);
  3660       break;
  3662     // We use T_VOID as marker for jump-table entries (labels) which
  3663     // need an internal word relocation.
  3664     case T_VOID: {
  3665       MachConstantNode* n = (MachConstantNode*) con.get_jobject();
  3666       // Fill the jump-table with a dummy word.  The real value is
  3667       // filled in later in fill_jump_table.
  3668       address dummy = (address) n;
  3669       constant_addr = _masm.address_constant(dummy);
  3670       // Expand jump-table
  3671       for (uint i = 1; i < n->outcnt(); i++) {
  3672         address temp_addr = _masm.address_constant(dummy + i);
  3673         assert(temp_addr, "consts section too small");
  3675       break;
  3677     case T_METADATA: {
  3678       Metadata* obj = con.get_metadata();
  3679       int metadata_index = _masm.oop_recorder()->find_index(obj);
  3680       constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
  3681       break;
  3683     default: ShouldNotReachHere();
  3685     assert(constant_addr, "consts section too small");
  3686     assert((constant_addr - _masm.code()->consts()->start()) == con.offset(), err_msg_res("must be: %d == %d", constant_addr - _masm.code()->consts()->start(), con.offset()));
  3690 int Compile::ConstantTable::find_offset(Constant& con) const {
  3691   int idx = _constants.find(con);
  3692   assert(idx != -1, "constant must be in constant table");
  3693   int offset = _constants.at(idx).offset();
  3694   assert(offset != -1, "constant table not emitted yet?");
  3695   return offset;
  3698 void Compile::ConstantTable::add(Constant& con) {
  3699   if (con.can_be_reused()) {
  3700     int idx = _constants.find(con);
  3701     if (idx != -1 && _constants.at(idx).can_be_reused()) {
  3702       _constants.adr_at(idx)->inc_freq(con.freq());  // increase the frequency by the current value
  3703       return;
  3706   (void) _constants.append(con);
  3709 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
  3710   Block* b = Compile::current()->cfg()->get_block_for_node(n);
  3711   Constant con(type, value, b->_freq);
  3712   add(con);
  3713   return con;
  3716 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
  3717   Constant con(metadata);
  3718   add(con);
  3719   return con;
  3722 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
  3723   jvalue value;
  3724   BasicType type = oper->type()->basic_type();
  3725   switch (type) {
  3726   case T_LONG:    value.j = oper->constantL(); break;
  3727   case T_FLOAT:   value.f = oper->constantF(); break;
  3728   case T_DOUBLE:  value.d = oper->constantD(); break;
  3729   case T_OBJECT:
  3730   case T_ADDRESS: value.l = (jobject) oper->constant(); break;
  3731   case T_METADATA: return add((Metadata*)oper->constant()); break;
  3732   default: guarantee(false, err_msg_res("unhandled type: %s", type2name(type)));
  3734   return add(n, type, value);
  3737 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
  3738   jvalue value;
  3739   // We can use the node pointer here to identify the right jump-table
  3740   // as this method is called from Compile::Fill_buffer right before
  3741   // the MachNodes are emitted and the jump-table is filled (means the
  3742   // MachNode pointers do not change anymore).
  3743   value.l = (jobject) n;
  3744   Constant con(T_VOID, value, next_jump_table_freq(), false);  // Labels of a jump-table cannot be reused.
  3745   add(con);
  3746   return con;
  3749 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
  3750   // If called from Compile::scratch_emit_size do nothing.
  3751   if (Compile::current()->in_scratch_emit_size())  return;
  3753   assert(labels.is_nonempty(), "must be");
  3754   assert((uint) labels.length() == n->outcnt(), err_msg_res("must be equal: %d == %d", labels.length(), n->outcnt()));
  3756   // Since MachConstantNode::constant_offset() also contains
  3757   // table_base_offset() we need to subtract the table_base_offset()
  3758   // to get the plain offset into the constant table.
  3759   int offset = n->constant_offset() - table_base_offset();
  3761   MacroAssembler _masm(&cb);
  3762   address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
  3764   for (uint i = 0; i < n->outcnt(); i++) {
  3765     address* constant_addr = &jump_table_base[i];
  3766     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)));
  3767     *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
  3768     cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
  3772 void Compile::dump_inlining() {
  3773   if (print_inlining() || print_intrinsics()) {
  3774     // Print inlining message for candidates that we couldn't inline
  3775     // for lack of space or non constant receiver
  3776     for (int i = 0; i < _late_inlines.length(); i++) {
  3777       CallGenerator* cg = _late_inlines.at(i);
  3778       cg->print_inlining_late("live nodes > LiveNodeCountInliningCutoff");
  3780     Unique_Node_List useful;
  3781     useful.push(root());
  3782     for (uint next = 0; next < useful.size(); ++next) {
  3783       Node* n  = useful.at(next);
  3784       if (n->is_Call() && n->as_Call()->generator() != NULL && n->as_Call()->generator()->call_node() == n) {
  3785         CallNode* call = n->as_Call();
  3786         CallGenerator* cg = call->generator();
  3787         cg->print_inlining_late("receiver not constant");
  3789       uint max = n->len();
  3790       for ( uint i = 0; i < max; ++i ) {
  3791         Node *m = n->in(i);
  3792         if ( m == NULL ) continue;
  3793         useful.push(m);
  3796     for (int i = 0; i < _print_inlining_list->length(); i++) {
  3797       tty->print(_print_inlining_list->adr_at(i)->ss()->as_string());
  3802 // Dump inlining replay data to the stream.
  3803 // Don't change thread state and acquire any locks.
  3804 void Compile::dump_inline_data(outputStream* out) {
  3805   InlineTree* inl_tree = ilt();
  3806   if (inl_tree != NULL) {
  3807     out->print(" inline %d", inl_tree->count());
  3808     inl_tree->dump_replay_data(out);
  3812 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
  3813   if (n1->Opcode() < n2->Opcode())      return -1;
  3814   else if (n1->Opcode() > n2->Opcode()) return 1;
  3816   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()));
  3817   for (uint i = 1; i < n1->req(); i++) {
  3818     if (n1->in(i) < n2->in(i))      return -1;
  3819     else if (n1->in(i) > n2->in(i)) return 1;
  3822   return 0;
  3825 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
  3826   Node* n1 = *n1p;
  3827   Node* n2 = *n2p;
  3829   return cmp_expensive_nodes(n1, n2);
  3832 void Compile::sort_expensive_nodes() {
  3833   if (!expensive_nodes_sorted()) {
  3834     _expensive_nodes->sort(cmp_expensive_nodes);
  3838 bool Compile::expensive_nodes_sorted() const {
  3839   for (int i = 1; i < _expensive_nodes->length(); i++) {
  3840     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
  3841       return false;
  3844   return true;
  3847 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
  3848   if (_expensive_nodes->length() == 0) {
  3849     return false;
  3852   assert(OptimizeExpensiveOps, "optimization off?");
  3854   // Take this opportunity to remove dead nodes from the list
  3855   int j = 0;
  3856   for (int i = 0; i < _expensive_nodes->length(); i++) {
  3857     Node* n = _expensive_nodes->at(i);
  3858     if (!n->is_unreachable(igvn)) {
  3859       assert(n->is_expensive(), "should be expensive");
  3860       _expensive_nodes->at_put(j, n);
  3861       j++;
  3864   _expensive_nodes->trunc_to(j);
  3866   // Then sort the list so that similar nodes are next to each other
  3867   // and check for at least two nodes of identical kind with same data
  3868   // inputs.
  3869   sort_expensive_nodes();
  3871   for (int i = 0; i < _expensive_nodes->length()-1; i++) {
  3872     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
  3873       return true;
  3877   return false;
  3880 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
  3881   if (_expensive_nodes->length() == 0) {
  3882     return;
  3885   assert(OptimizeExpensiveOps, "optimization off?");
  3887   // Sort to bring similar nodes next to each other and clear the
  3888   // control input of nodes for which there's only a single copy.
  3889   sort_expensive_nodes();
  3891   int j = 0;
  3892   int identical = 0;
  3893   int i = 0;
  3894   for (; i < _expensive_nodes->length()-1; i++) {
  3895     assert(j <= i, "can't write beyond current index");
  3896     if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
  3897       identical++;
  3898       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3899       continue;
  3901     if (identical > 0) {
  3902       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3903       identical = 0;
  3904     } else {
  3905       Node* n = _expensive_nodes->at(i);
  3906       igvn.hash_delete(n);
  3907       n->set_req(0, NULL);
  3908       igvn.hash_insert(n);
  3911   if (identical > 0) {
  3912     _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
  3913   } else if (_expensive_nodes->length() >= 1) {
  3914     Node* n = _expensive_nodes->at(i);
  3915     igvn.hash_delete(n);
  3916     n->set_req(0, NULL);
  3917     igvn.hash_insert(n);
  3919   _expensive_nodes->trunc_to(j);
  3922 void Compile::add_expensive_node(Node * n) {
  3923   assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
  3924   assert(n->is_expensive(), "expensive nodes with non-null control here only");
  3925   assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
  3926   if (OptimizeExpensiveOps) {
  3927     _expensive_nodes->append(n);
  3928   } else {
  3929     // Clear control input and let IGVN optimize expensive nodes if
  3930     // OptimizeExpensiveOps is off.
  3931     n->set_req(0, NULL);
  3935 /**
  3936  * Remove the speculative part of types and clean up the graph
  3937  */
  3938 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
  3939   if (UseTypeSpeculation) {
  3940     Unique_Node_List worklist;
  3941     worklist.push(root());
  3942     int modified = 0;
  3943     // Go over all type nodes that carry a speculative type, drop the
  3944     // speculative part of the type and enqueue the node for an igvn
  3945     // which may optimize it out.
  3946     for (uint next = 0; next < worklist.size(); ++next) {
  3947       Node *n  = worklist.at(next);
  3948       if (n->is_Type()) {
  3949         TypeNode* tn = n->as_Type();
  3950         const Type* t = tn->type();
  3951         const Type* t_no_spec = t->remove_speculative();
  3952         if (t_no_spec != t) {
  3953           bool in_hash = igvn.hash_delete(n);
  3954           assert(in_hash, "node should be in igvn hash table");
  3955           tn->set_type(t_no_spec);
  3956           igvn.hash_insert(n);
  3957           igvn._worklist.push(n); // give it a chance to go away
  3958           modified++;
  3961       uint max = n->len();
  3962       for( uint i = 0; i < max; ++i ) {
  3963         Node *m = n->in(i);
  3964         if (not_a_node(m))  continue;
  3965         worklist.push(m);
  3968     // Drop the speculative part of all types in the igvn's type table
  3969     igvn.remove_speculative_types();
  3970     if (modified > 0) {
  3971       igvn.optimize();
  3973 #ifdef ASSERT
  3974     // Verify that after the IGVN is over no speculative type has resurfaced
  3975     worklist.clear();
  3976     worklist.push(root());
  3977     for (uint next = 0; next < worklist.size(); ++next) {
  3978       Node *n  = worklist.at(next);
  3979       const Type* t = igvn.type(n);
  3980       assert(t == t->remove_speculative(), "no more speculative types");
  3981       if (n->is_Type()) {
  3982         t = n->as_Type()->type();
  3983         assert(t == t->remove_speculative(), "no more speculative types");
  3985       uint max = n->len();
  3986       for( uint i = 0; i < max; ++i ) {
  3987         Node *m = n->in(i);
  3988         if (not_a_node(m))  continue;
  3989         worklist.push(m);
  3992     igvn.check_no_speculative_types();
  3993 #endif
  3997 // Auxiliary method to support randomized stressing/fuzzing.
  3998 //
  3999 // This method can be called the arbitrary number of times, with current count
  4000 // as the argument. The logic allows selecting a single candidate from the
  4001 // running list of candidates as follows:
  4002 //    int count = 0;
  4003 //    Cand* selected = null;
  4004 //    while(cand = cand->next()) {
  4005 //      if (randomized_select(++count)) {
  4006 //        selected = cand;
  4007 //      }
  4008 //    }
  4009 //
  4010 // Including count equalizes the chances any candidate is "selected".
  4011 // This is useful when we don't have the complete list of candidates to choose
  4012 // from uniformly. In this case, we need to adjust the randomicity of the
  4013 // selection, or else we will end up biasing the selection towards the latter
  4014 // candidates.
  4015 //
  4016 // Quick back-envelope calculation shows that for the list of n candidates
  4017 // the equal probability for the candidate to persist as "best" can be
  4018 // achieved by replacing it with "next" k-th candidate with the probability
  4019 // of 1/k. It can be easily shown that by the end of the run, the
  4020 // probability for any candidate is converged to 1/n, thus giving the
  4021 // uniform distribution among all the candidates.
  4022 //
  4023 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
  4024 #define RANDOMIZED_DOMAIN_POW 29
  4025 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
  4026 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
  4027 bool Compile::randomized_select(int count) {
  4028   assert(count > 0, "only positive");
  4029   return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);

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