src/share/vm/opto/parse3.cpp

Fri, 20 Aug 2010 23:40:30 -0700

author
jrose
date
Fri, 20 Aug 2010 23:40:30 -0700
changeset 2101
4b29a725c43c
parent 1907
c18cbe5936b8
child 2314
f95d63e2154a
permissions
-rw-r--r--

6912064: type profiles need to be exploited more for dynamic language support
Reviewed-by: kvn

     1 /*
     2  * Copyright (c) 1998, 2010, 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 "incls/_precompiled.incl"
    26 #include "incls/_parse3.cpp.incl"
    28 //=============================================================================
    29 // Helper methods for _get* and _put* bytecodes
    30 //=============================================================================
    31 bool Parse::static_field_ok_in_clinit(ciField *field, ciMethod *method) {
    32   // Could be the field_holder's <clinit> method, or <clinit> for a subklass.
    33   // Better to check now than to Deoptimize as soon as we execute
    34   assert( field->is_static(), "Only check if field is static");
    35   // is_being_initialized() is too generous.  It allows access to statics
    36   // by threads that are not running the <clinit> before the <clinit> finishes.
    37   // return field->holder()->is_being_initialized();
    39   // The following restriction is correct but conservative.
    40   // It is also desirable to allow compilation of methods called from <clinit>
    41   // but this generated code will need to be made safe for execution by
    42   // other threads, or the transition from interpreted to compiled code would
    43   // need to be guarded.
    44   ciInstanceKlass *field_holder = field->holder();
    46   bool access_OK = false;
    47   if (method->holder()->is_subclass_of(field_holder)) {
    48     if (method->is_static()) {
    49       if (method->name() == ciSymbol::class_initializer_name()) {
    50         // OK to access static fields inside initializer
    51         access_OK = true;
    52       }
    53     } else {
    54       if (method->name() == ciSymbol::object_initializer_name()) {
    55         // It's also OK to access static fields inside a constructor,
    56         // because any thread calling the constructor must first have
    57         // synchronized on the class by executing a '_new' bytecode.
    58         access_OK = true;
    59       }
    60     }
    61   }
    63   return access_OK;
    65 }
    68 void Parse::do_field_access(bool is_get, bool is_field) {
    69   bool will_link;
    70   ciField* field = iter().get_field(will_link);
    71   assert(will_link, "getfield: typeflow responsibility");
    73   ciInstanceKlass* field_holder = field->holder();
    75   if (is_field == field->is_static()) {
    76     // Interpreter will throw java_lang_IncompatibleClassChangeError
    77     // Check this before allowing <clinit> methods to access static fields
    78     uncommon_trap(Deoptimization::Reason_unhandled,
    79                   Deoptimization::Action_none);
    80     return;
    81   }
    83   if (!is_field && !field_holder->is_initialized()) {
    84     if (!static_field_ok_in_clinit(field, method())) {
    85       uncommon_trap(Deoptimization::Reason_uninitialized,
    86                     Deoptimization::Action_reinterpret,
    87                     NULL, "!static_field_ok_in_clinit");
    88       return;
    89     }
    90   }
    92   assert(field->will_link(method()->holder(), bc()), "getfield: typeflow responsibility");
    94   // Note:  We do not check for an unloaded field type here any more.
    96   // Generate code for the object pointer.
    97   Node* obj;
    98   if (is_field) {
    99     int obj_depth = is_get ? 0 : field->type()->size();
   100     obj = do_null_check(peek(obj_depth), T_OBJECT);
   101     // Compile-time detect of null-exception?
   102     if (stopped())  return;
   104     const TypeInstPtr *tjp = TypeInstPtr::make(TypePtr::NotNull, iter().get_declared_field_holder());
   105     assert(_gvn.type(obj)->higher_equal(tjp), "cast_up is no longer needed");
   107     if (is_get) {
   108       --_sp;  // pop receiver before getting
   109       do_get_xxx(tjp, obj, field, is_field);
   110     } else {
   111       do_put_xxx(tjp, obj, field, is_field);
   112       --_sp;  // pop receiver after putting
   113     }
   114   } else {
   115     const TypeKlassPtr* tkp = TypeKlassPtr::make(field_holder);
   116     obj = _gvn.makecon(tkp);
   117     if (is_get) {
   118       do_get_xxx(tkp, obj, field, is_field);
   119     } else {
   120       do_put_xxx(tkp, obj, field, is_field);
   121     }
   122   }
   123 }
   126 void Parse::do_get_xxx(const TypePtr* obj_type, Node* obj, ciField* field, bool is_field) {
   127   // Does this field have a constant value?  If so, just push the value.
   128   if (field->is_constant()) {
   129     if (field->is_static()) {
   130       // final static field
   131       if (push_constant(field->constant_value()))
   132         return;
   133     }
   134     else {
   135       // final non-static field of a trusted class ({java,sun}.dyn
   136       // classes).
   137       if (obj->is_Con()) {
   138         const TypeOopPtr* oop_ptr = obj->bottom_type()->isa_oopptr();
   139         ciObject* constant_oop = oop_ptr->const_oop();
   140         ciConstant constant = field->constant_value_of(constant_oop);
   142         if (push_constant(constant, true))
   143           return;
   144       }
   145     }
   146   }
   148   ciType* field_klass = field->type();
   149   bool is_vol = field->is_volatile();
   151   // Compute address and memory type.
   152   int offset = field->offset_in_bytes();
   153   const TypePtr* adr_type = C->alias_type(field)->adr_type();
   154   Node *adr = basic_plus_adr(obj, obj, offset);
   155   BasicType bt = field->layout_type();
   157   // Build the resultant type of the load
   158   const Type *type;
   160   bool must_assert_null = false;
   162   if( bt == T_OBJECT ) {
   163     if (!field->type()->is_loaded()) {
   164       type = TypeInstPtr::BOTTOM;
   165       must_assert_null = true;
   166     } else if (field->is_constant() && field->is_static()) {
   167       // This can happen if the constant oop is non-perm.
   168       ciObject* con = field->constant_value().as_object();
   169       // Do not "join" in the previous type; it doesn't add value,
   170       // and may yield a vacuous result if the field is of interface type.
   171       type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
   172       assert(type != NULL, "field singleton type must be consistent");
   173     } else {
   174       type = TypeOopPtr::make_from_klass(field_klass->as_klass());
   175     }
   176   } else {
   177     type = Type::get_const_basic_type(bt);
   178   }
   179   // Build the load.
   180   Node* ld = make_load(NULL, adr, type, bt, adr_type, is_vol);
   182   // Adjust Java stack
   183   if (type2size[bt] == 1)
   184     push(ld);
   185   else
   186     push_pair(ld);
   188   if (must_assert_null) {
   189     // Do not take a trap here.  It's possible that the program
   190     // will never load the field's class, and will happily see
   191     // null values in this field forever.  Don't stumble into a
   192     // trap for such a program, or we might get a long series
   193     // of useless recompilations.  (Or, we might load a class
   194     // which should not be loaded.)  If we ever see a non-null
   195     // value, we will then trap and recompile.  (The trap will
   196     // not need to mention the class index, since the class will
   197     // already have been loaded if we ever see a non-null value.)
   198     // uncommon_trap(iter().get_field_signature_index());
   199 #ifndef PRODUCT
   200     if (PrintOpto && (Verbose || WizardMode)) {
   201       method()->print_name(); tty->print_cr(" asserting nullness of field at bci: %d", bci());
   202     }
   203 #endif
   204     if (C->log() != NULL) {
   205       C->log()->elem("assert_null reason='field' klass='%d'",
   206                      C->log()->identify(field->type()));
   207     }
   208     // If there is going to be a trap, put it at the next bytecode:
   209     set_bci(iter().next_bci());
   210     do_null_assert(peek(), T_OBJECT);
   211     set_bci(iter().cur_bci()); // put it back
   212   }
   214   // If reference is volatile, prevent following memory ops from
   215   // floating up past the volatile read.  Also prevents commoning
   216   // another volatile read.
   217   if (field->is_volatile()) {
   218     // Memory barrier includes bogus read of value to force load BEFORE membar
   219     insert_mem_bar(Op_MemBarAcquire, ld);
   220   }
   221 }
   223 void Parse::do_put_xxx(const TypePtr* obj_type, Node* obj, ciField* field, bool is_field) {
   224   bool is_vol = field->is_volatile();
   225   // If reference is volatile, prevent following memory ops from
   226   // floating down past the volatile write.  Also prevents commoning
   227   // another volatile read.
   228   if (is_vol)  insert_mem_bar(Op_MemBarRelease);
   230   // Compute address and memory type.
   231   int offset = field->offset_in_bytes();
   232   const TypePtr* adr_type = C->alias_type(field)->adr_type();
   233   Node* adr = basic_plus_adr(obj, obj, offset);
   234   BasicType bt = field->layout_type();
   235   // Value to be stored
   236   Node* val = type2size[bt] == 1 ? pop() : pop_pair();
   237   // Round doubles before storing
   238   if (bt == T_DOUBLE)  val = dstore_rounding(val);
   240   // Store the value.
   241   Node* store;
   242   if (bt == T_OBJECT) {
   243     const TypeOopPtr* field_type;
   244     if (!field->type()->is_loaded()) {
   245       field_type = TypeInstPtr::BOTTOM;
   246     } else {
   247       field_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
   248     }
   249     store = store_oop_to_object( control(), obj, adr, adr_type, val, field_type, bt);
   250   } else {
   251     store = store_to_memory( control(), adr, val, bt, adr_type, is_vol );
   252   }
   254   // If reference is volatile, prevent following volatiles ops from
   255   // floating up before the volatile write.
   256   if (is_vol) {
   257     // First place the specific membar for THIS volatile index. This first
   258     // membar is dependent on the store, keeping any other membars generated
   259     // below from floating up past the store.
   260     int adr_idx = C->get_alias_index(adr_type);
   261     insert_mem_bar_volatile(Op_MemBarVolatile, adr_idx, store);
   263     // Now place a membar for AliasIdxBot for the unknown yet-to-be-parsed
   264     // volatile alias indices. Skip this if the membar is redundant.
   265     if (adr_idx != Compile::AliasIdxBot) {
   266       insert_mem_bar_volatile(Op_MemBarVolatile, Compile::AliasIdxBot, store);
   267     }
   269     // Finally, place alias-index-specific membars for each volatile index
   270     // that isn't the adr_idx membar. Typically there's only 1 or 2.
   271     for( int i = Compile::AliasIdxRaw; i < C->num_alias_types(); i++ ) {
   272       if (i != adr_idx && C->alias_type(i)->is_volatile()) {
   273         insert_mem_bar_volatile(Op_MemBarVolatile, i, store);
   274       }
   275     }
   276   }
   278   // If the field is final, the rules of Java say we are in <init> or <clinit>.
   279   // Note the presence of writes to final non-static fields, so that we
   280   // can insert a memory barrier later on to keep the writes from floating
   281   // out of the constructor.
   282   if (is_field && field->is_final()) {
   283     set_wrote_final(true);
   284   }
   285 }
   288 bool Parse::push_constant(ciConstant constant, bool require_constant) {
   289   switch (constant.basic_type()) {
   290   case T_BOOLEAN:  push( intcon(constant.as_boolean()) ); break;
   291   case T_INT:      push( intcon(constant.as_int())     ); break;
   292   case T_CHAR:     push( intcon(constant.as_char())    ); break;
   293   case T_BYTE:     push( intcon(constant.as_byte())    ); break;
   294   case T_SHORT:    push( intcon(constant.as_short())   ); break;
   295   case T_FLOAT:    push( makecon(TypeF::make(constant.as_float())) );  break;
   296   case T_DOUBLE:   push_pair( makecon(TypeD::make(constant.as_double())) );  break;
   297   case T_LONG:     push_pair( longcon(constant.as_long()) ); break;
   298   case T_ARRAY:
   299   case T_OBJECT: {
   300     // cases:
   301     //   can_be_constant    = (oop not scavengable || ScavengeRootsInCode != 0)
   302     //   should_be_constant = (oop not scavengable || ScavengeRootsInCode >= 2)
   303     // An oop is not scavengable if it is in the perm gen.
   304     ciObject* oop_constant = constant.as_object();
   305     if (oop_constant->is_null_object()) {
   306       push( zerocon(T_OBJECT) );
   307       break;
   308     } else if (require_constant || oop_constant->should_be_constant()) {
   309       push( makecon(TypeOopPtr::make_from_constant(oop_constant, require_constant)) );
   310       break;
   311     } else {
   312       // we cannot inline the oop, but we can use it later to narrow a type
   313       return false;
   314     }
   315   }
   316   case T_ILLEGAL: {
   317     // Invalid ciConstant returned due to OutOfMemoryError in the CI
   318     assert(C->env()->failing(), "otherwise should not see this");
   319     // These always occur because of object types; we are going to
   320     // bail out anyway, so make the stack depths match up
   321     push( zerocon(T_OBJECT) );
   322     return false;
   323   }
   324   default:
   325     ShouldNotReachHere();
   326     return false;
   327   }
   329   // success
   330   return true;
   331 }
   335 //=============================================================================
   336 void Parse::do_anewarray() {
   337   bool will_link;
   338   ciKlass* klass = iter().get_klass(will_link);
   340   // Uncommon Trap when class that array contains is not loaded
   341   // we need the loaded class for the rest of graph; do not
   342   // initialize the container class (see Java spec)!!!
   343   assert(will_link, "anewarray: typeflow responsibility");
   345   ciObjArrayKlass* array_klass = ciObjArrayKlass::make(klass);
   346   // Check that array_klass object is loaded
   347   if (!array_klass->is_loaded()) {
   348     // Generate uncommon_trap for unloaded array_class
   349     uncommon_trap(Deoptimization::Reason_unloaded,
   350                   Deoptimization::Action_reinterpret,
   351                   array_klass);
   352     return;
   353   }
   355   kill_dead_locals();
   357   const TypeKlassPtr* array_klass_type = TypeKlassPtr::make(array_klass);
   358   Node* count_val = pop();
   359   Node* obj = new_array(makecon(array_klass_type), count_val, 1);
   360   push(obj);
   361 }
   364 void Parse::do_newarray(BasicType elem_type) {
   365   kill_dead_locals();
   367   Node*   count_val = pop();
   368   const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(elem_type));
   369   Node*   obj = new_array(makecon(array_klass), count_val, 1);
   370   // Push resultant oop onto stack
   371   push(obj);
   372 }
   374 // Expand simple expressions like new int[3][5] and new Object[2][nonConLen].
   375 // Also handle the degenerate 1-dimensional case of anewarray.
   376 Node* Parse::expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs) {
   377   Node* length = lengths[0];
   378   assert(length != NULL, "");
   379   Node* array = new_array(makecon(TypeKlassPtr::make(array_klass)), length, nargs);
   380   if (ndimensions > 1) {
   381     jint length_con = find_int_con(length, -1);
   382     guarantee(length_con >= 0, "non-constant multianewarray");
   383     ciArrayKlass* array_klass_1 = array_klass->as_obj_array_klass()->element_klass()->as_array_klass();
   384     const TypePtr* adr_type = TypeAryPtr::OOPS;
   385     const TypeOopPtr*    elemtype = _gvn.type(array)->is_aryptr()->elem()->make_oopptr();
   386     const intptr_t header   = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
   387     for (jint i = 0; i < length_con; i++) {
   388       Node*    elem   = expand_multianewarray(array_klass_1, &lengths[1], ndimensions-1, nargs);
   389       intptr_t offset = header + ((intptr_t)i << LogBytesPerHeapOop);
   390       Node*    eaddr  = basic_plus_adr(array, offset);
   391       store_oop_to_array(control(), array, eaddr, adr_type, elem, elemtype, T_OBJECT);
   392     }
   393   }
   394   return array;
   395 }
   397 void Parse::do_multianewarray() {
   398   int ndimensions = iter().get_dimensions();
   400   // the m-dimensional array
   401   bool will_link;
   402   ciArrayKlass* array_klass = iter().get_klass(will_link)->as_array_klass();
   403   assert(will_link, "multianewarray: typeflow responsibility");
   405   // Note:  Array classes are always initialized; no is_initialized check.
   407   enum { MAX_DIMENSION = 5 };
   408   if (ndimensions > MAX_DIMENSION || ndimensions <= 0) {
   409     uncommon_trap(Deoptimization::Reason_unhandled,
   410                   Deoptimization::Action_none);
   411     return;
   412   }
   414   kill_dead_locals();
   416   // get the lengths from the stack (first dimension is on top)
   417   Node* length[MAX_DIMENSION+1];
   418   length[ndimensions] = NULL;  // terminating null for make_runtime_call
   419   int j;
   420   for (j = ndimensions-1; j >= 0 ; j--) length[j] = pop();
   422   // The original expression was of this form: new T[length0][length1]...
   423   // It is often the case that the lengths are small (except the last).
   424   // If that happens, use the fast 1-d creator a constant number of times.
   425   const jint expand_limit = MIN2((juint)MultiArrayExpandLimit, (juint)100);
   426   jint expand_count = 1;        // count of allocations in the expansion
   427   jint expand_fanout = 1;       // running total fanout
   428   for (j = 0; j < ndimensions-1; j++) {
   429     jint dim_con = find_int_con(length[j], -1);
   430     expand_fanout *= dim_con;
   431     expand_count  += expand_fanout; // count the level-J sub-arrays
   432     if (dim_con <= 0
   433         || dim_con > expand_limit
   434         || expand_count > expand_limit) {
   435       expand_count = 0;
   436       break;
   437     }
   438   }
   440   // Can use multianewarray instead of [a]newarray if only one dimension,
   441   // or if all non-final dimensions are small constants.
   442   if (ndimensions == 1 || (1 <= expand_count && expand_count <= expand_limit)) {
   443     Node* obj = NULL;
   444     // Set the original stack and the reexecute bit for the interpreter
   445     // to reexecute the multianewarray bytecode if deoptimization happens.
   446     // Do it unconditionally even for one dimension multianewarray.
   447     // Note: the reexecute bit will be set in GraphKit::add_safepoint_edges()
   448     // when AllocateArray node for newarray is created.
   449     { PreserveReexecuteState preexecs(this);
   450       _sp += ndimensions;
   451       // Pass 0 as nargs since uncommon trap code does not need to restore stack.
   452       obj = expand_multianewarray(array_klass, &length[0], ndimensions, 0);
   453     } //original reexecute and sp are set back here
   454     push(obj);
   455     return;
   456   }
   458   address fun = NULL;
   459   switch (ndimensions) {
   460   //case 1: Actually, there is no case 1.  It's handled by new_array.
   461   case 2: fun = OptoRuntime::multianewarray2_Java(); break;
   462   case 3: fun = OptoRuntime::multianewarray3_Java(); break;
   463   case 4: fun = OptoRuntime::multianewarray4_Java(); break;
   464   case 5: fun = OptoRuntime::multianewarray5_Java(); break;
   465   default: ShouldNotReachHere();
   466   };
   468   Node* c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
   469                               OptoRuntime::multianewarray_Type(ndimensions),
   470                               fun, NULL, TypeRawPtr::BOTTOM,
   471                               makecon(TypeKlassPtr::make(array_klass)),
   472                               length[0], length[1], length[2],
   473                               length[3], length[4]);
   474   Node* res = _gvn.transform(new (C, 1) ProjNode(c, TypeFunc::Parms));
   476   const Type* type = TypeOopPtr::make_from_klass_raw(array_klass);
   478   // Improve the type:  We know it's not null, exact, and of a given length.
   479   type = type->is_ptr()->cast_to_ptr_type(TypePtr::NotNull);
   480   type = type->is_aryptr()->cast_to_exactness(true);
   482   const TypeInt* ltype = _gvn.find_int_type(length[0]);
   483   if (ltype != NULL)
   484     type = type->is_aryptr()->cast_to_size(ltype);
   486   // We cannot sharpen the nested sub-arrays, since the top level is mutable.
   488   Node* cast = _gvn.transform( new (C, 2) CheckCastPPNode(control(), res, type) );
   489   push(cast);
   491   // Possible improvements:
   492   // - Make a fast path for small multi-arrays.  (W/ implicit init. loops.)
   493   // - Issue CastII against length[*] values, to TypeInt::POS.
   494 }

mercurial