1 /*
   2  * Copyright (c) 1998, 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  */
  24 
  25 #include "precompiled.hpp"
  26 #include "compiler/compileLog.hpp"
  27 #include "interpreter/linkResolver.hpp"
  28 #include "memory/universe.inline.hpp"
  29 #include "oops/objArrayKlass.hpp"
  30 #include "opto/addnode.hpp"
  31 #include "opto/castnode.hpp"
  32 #include "opto/memnode.hpp"
  33 #include "opto/parse.hpp"
  34 #include "opto/rootnode.hpp"
  35 #include "opto/runtime.hpp"
  36 #include "opto/subnode.hpp"
  37 #include "runtime/deoptimization.hpp"
  38 #include "runtime/handles.inline.hpp"
  39 
  40 //=============================================================================
  41 // Helper methods for _get* and _put* bytecodes
  42 //=============================================================================
  43 bool Parse::static_field_ok_in_clinit(ciField *field, ciMethod *method) {
  44   // Could be the field_holder's <clinit> method, or <clinit> for a subklass.
  45   // Better to check now than to Deoptimize as soon as we execute
  46   assert( field->is_static(), "Only check if field is static");
  47   // is_being_initialized() is too generous.  It allows access to statics
  48   // by threads that are not running the <clinit> before the <clinit> finishes.
  49   // return field->holder()->is_being_initialized();
  50 
  51   // The following restriction is correct but conservative.
  52   // It is also desirable to allow compilation of methods called from <clinit>
  53   // but this generated code will need to be made safe for execution by
  54   // other threads, or the transition from interpreted to compiled code would
  55   // need to be guarded.
  56   ciInstanceKlass *field_holder = field->holder();
  57 
  58   bool access_OK = false;
  59   if (method->holder()->is_subclass_of(field_holder)) {
  60     if (method->is_static()) {
  61       if (method->name() == ciSymbol::class_initializer_name()) {
  62         // OK to access static fields inside initializer
  63         access_OK = true;
  64       }
  65     } else {
  66       if (method->name() == ciSymbol::object_initializer_name()) {
  67         // It's also OK to access static fields inside a constructor,
  68         // because any thread calling the constructor must first have
  69         // synchronized on the class by executing a '_new' bytecode.
  70         access_OK = true;
  71       }
  72     }
  73   }
  74 
  75   return access_OK;
  76 
  77 }
  78 
  79 
  80 void Parse::do_field_access(bool is_get, bool is_field) {
  81   bool will_link;
  82   ciField* field = iter().get_field(will_link);
  83   assert(will_link, "getfield: typeflow responsibility");
  84 
  85   ciInstanceKlass* field_holder = field->holder();
  86 
  87   if (is_field == field->is_static()) {
  88     // Interpreter will throw java_lang_IncompatibleClassChangeError
  89     // Check this before allowing <clinit> methods to access static fields
  90     uncommon_trap(Deoptimization::Reason_unhandled,
  91                   Deoptimization::Action_none);
  92     return;
  93   }
  94 
  95   if (!is_field && !field_holder->is_initialized()) {
  96     if (!static_field_ok_in_clinit(field, method())) {
  97       uncommon_trap(Deoptimization::Reason_uninitialized,
  98                     Deoptimization::Action_reinterpret,
  99                     NULL, "!static_field_ok_in_clinit");
 100       return;
 101     }
 102   }
 103 
 104   // Deoptimize on putfield writes to call site target field.
 105   if (!is_get && field->is_call_site_target()) {
 106     uncommon_trap(Deoptimization::Reason_unhandled,
 107                   Deoptimization::Action_reinterpret,
 108                   NULL, "put to call site target field");
 109     return;
 110   }
 111 
 112   assert(field->will_link(method()->holder(), bc()), "getfield: typeflow responsibility");
 113 
 114   // Note:  We do not check for an unloaded field type here any more.
 115 
 116   // Generate code for the object pointer.
 117   Node* obj;
 118   if (is_field) {
 119     int obj_depth = is_get ? 0 : field->type()->size();
 120     obj = null_check(peek(obj_depth));
 121     // Compile-time detect of null-exception?
 122     if (stopped())  return;
 123 
 124 #ifdef ASSERT
 125     const TypeInstPtr *tjp = TypeInstPtr::make(TypePtr::NotNull, iter().get_declared_field_holder());
 126     assert(_gvn.type(obj)->higher_equal(tjp), "cast_up is no longer needed");
 127 #endif
 128 
 129     if (is_get) {
 130       (void) pop();  // pop receiver before getting
 131       do_get_xxx(obj, field, is_field);
 132     } else {
 133       do_put_xxx(obj, field, is_field);
 134       (void) pop();  // pop receiver after putting
 135     }
 136   } else {
 137     const TypeInstPtr* tip = TypeInstPtr::make(field_holder->java_mirror());
 138     obj = _gvn.makecon(tip);
 139     if (is_get) {
 140       do_get_xxx(obj, field, is_field);
 141     } else {
 142       do_put_xxx(obj, field, is_field);
 143     }
 144   }
 145 }
 146 
 147 
 148 void Parse::do_get_xxx(Node* obj, ciField* field, bool is_field) {
 149   // Does this field have a constant value?  If so, just push the value.
 150   if (field->is_constant()) {
 151     // final or stable field
 152     const Type* con_type = Type::make_constant(field, obj);
 153     if (con_type != NULL) {
 154       push_node(con_type->basic_type(), makecon(con_type));
 155       return;
 156     }
 157   }
 158 
 159   ciType* field_klass = field->type();
 160   bool is_vol = field->is_volatile();
 161 
 162   // Compute address and memory type.
 163   int offset = field->offset_in_bytes();
 164   const TypePtr* adr_type = C->alias_type(field)->adr_type();
 165   Node *adr = basic_plus_adr(obj, obj, offset);
 166   BasicType bt = field->layout_type();
 167 
 168   // Build the resultant type of the load
 169   const Type *type;
 170 
 171   bool must_assert_null = false;
 172 
 173   if( bt == T_OBJECT ) {
 174     if (!field->type()->is_loaded()) {
 175       type = TypeInstPtr::BOTTOM;
 176       must_assert_null = true;
 177     } else if (field->is_constant() && field->is_static()) {
 178       // This can happen if the constant oop is non-perm.
 179       ciObject* con = field->constant_value().as_object();
 180       // Do not "join" in the previous type; it doesn't add value,
 181       // and may yield a vacuous result if the field is of interface type.
 182       type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
 183       assert(type != NULL, "field singleton type must be consistent");
 184     } else {
 185       type = TypeOopPtr::make_from_klass(field_klass->as_klass());
 186     }
 187   } else {
 188     type = Type::get_const_basic_type(bt);
 189   }
 190   if (support_IRIW_for_not_multiple_copy_atomic_cpu && field->is_volatile()) {
 191     insert_mem_bar(Op_MemBarVolatile);   // StoreLoad barrier
 192   }
 193   // Build the load.
 194   //
 195   MemNode::MemOrd mo = is_vol ? MemNode::acquire : MemNode::unordered;
 196   bool needs_atomic_access = is_vol || AlwaysAtomicAccesses;
 197   Node* ld = make_load(NULL, adr, type, bt, adr_type, mo, LoadNode::DependsOnlyOnTest, needs_atomic_access);
 198 
 199   // Adjust Java stack
 200   if (type2size[bt] == 1)
 201     push(ld);
 202   else
 203     push_pair(ld);
 204 
 205   if (must_assert_null) {
 206     // Do not take a trap here.  It's possible that the program
 207     // will never load the field's class, and will happily see
 208     // null values in this field forever.  Don't stumble into a
 209     // trap for such a program, or we might get a long series
 210     // of useless recompilations.  (Or, we might load a class
 211     // which should not be loaded.)  If we ever see a non-null
 212     // value, we will then trap and recompile.  (The trap will
 213     // not need to mention the class index, since the class will
 214     // already have been loaded if we ever see a non-null value.)
 215     // uncommon_trap(iter().get_field_signature_index());
 216 #ifndef PRODUCT
 217     if (PrintOpto && (Verbose || WizardMode)) {
 218       method()->print_name(); tty->print_cr(" asserting nullness of field at bci: %d", bci());
 219     }
 220 #endif
 221     if (C->log() != NULL) {
 222       C->log()->elem("assert_null reason='field' klass='%d'",
 223                      C->log()->identify(field->type()));
 224     }
 225     // If there is going to be a trap, put it at the next bytecode:
 226     set_bci(iter().next_bci());
 227     null_assert(peek());
 228     set_bci(iter().cur_bci()); // put it back
 229   }
 230 
 231   // If reference is volatile, prevent following memory ops from
 232   // floating up past the volatile read.  Also prevents commoning
 233   // another volatile read.
 234   if (field->is_volatile()) {
 235     // Memory barrier includes bogus read of value to force load BEFORE membar
 236     insert_mem_bar(Op_MemBarAcquire, ld);
 237   }
 238 }
 239 
 240 void Parse::do_put_xxx(Node* obj, ciField* field, bool is_field) {
 241   bool is_vol = field->is_volatile();
 242   // If reference is volatile, prevent following memory ops from
 243   // floating down past the volatile write.  Also prevents commoning
 244   // another volatile read.
 245   if (is_vol)  insert_mem_bar(Op_MemBarRelease);
 246 
 247   // Compute address and memory type.
 248   int offset = field->offset_in_bytes();
 249   const TypePtr* adr_type = C->alias_type(field)->adr_type();
 250   Node* adr = basic_plus_adr(obj, obj, offset);
 251   BasicType bt = field->layout_type();
 252   // Value to be stored
 253   Node* val = type2size[bt] == 1 ? pop() : pop_pair();
 254   // Round doubles before storing
 255   if (bt == T_DOUBLE)  val = dstore_rounding(val);
 256 
 257   // Conservatively release stores of object references.
 258   const MemNode::MemOrd mo =
 259     is_vol ?
 260     // Volatile fields need releasing stores.
 261     MemNode::release :
 262     // Non-volatile fields also need releasing stores if they hold an
 263     // object reference, because the object reference might point to
 264     // a freshly created object.
 265     StoreNode::release_if_reference(bt);
 266 
 267   // Store the value.
 268   Node* store;
 269   if (bt == T_OBJECT) {
 270     const TypeOopPtr* field_type;
 271     if (!field->type()->is_loaded()) {
 272       field_type = TypeInstPtr::BOTTOM;
 273     } else {
 274       field_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
 275     }
 276     store = store_oop_to_object(control(), obj, adr, adr_type, val, field_type, bt, mo);
 277   } else {
 278     bool needs_atomic_access = is_vol || AlwaysAtomicAccesses;
 279     store = store_to_memory(control(), adr, val, bt, adr_type, mo, needs_atomic_access);
 280   }
 281 
 282   // If reference is volatile, prevent following volatiles ops from
 283   // floating up before the volatile write.
 284   if (is_vol) {
 285     // If not multiple copy atomic, we do the MemBarVolatile before the load.
 286     if (!support_IRIW_for_not_multiple_copy_atomic_cpu) {
 287       insert_mem_bar(Op_MemBarVolatile); // Use fat membar
 288     }
 289     // Remember we wrote a volatile field.
 290     // For not multiple copy atomic cpu (ppc64) a barrier should be issued
 291     // in constructors which have such stores. See do_exits() in parse1.cpp.
 292     if (is_field) {
 293       set_wrote_volatile(true);
 294     }
 295   }
 296 
 297   if (is_field) {
 298     set_wrote_fields(true);
 299   }
 300 
 301   // If the field is final, the rules of Java say we are in <init> or <clinit>.
 302   // Note the presence of writes to final non-static fields, so that we
 303   // can insert a memory barrier later on to keep the writes from floating
 304   // out of the constructor.
 305   // Any method can write a @Stable field; insert memory barriers after those also.
 306   if (is_field && (field->is_final() || field->is_stable())) {
 307     if (field->is_final()) {
 308         set_wrote_final(true);
 309     }
 310     if (field->is_stable()) {
 311         set_wrote_stable(true);
 312     }
 313 
 314     // Preserve allocation ptr to create precedent edge to it in membar
 315     // generated on exit from constructor.
 316     if (AllocateNode::Ideal_allocation(obj, &_gvn) != NULL) {
 317       if (field->is_final()) {

 318         set_alloc_with_final(obj);
 319       }
 320       if (field->is_stable()) {
 321         set_alloc_with_stable(obj);
 322       }
 323     }
 324     else if (field->is_stable()) {
 325       // stable field doesn't have allocation, set alloc_with_stable as NULL
 326       // because its initialize vlaue is NodeSentinel. If not set NULL, 
 327       // next set_alloc_with_stable call might set none-NULL value successfully.  
 328       set_alloc_with_stable(NULL);
 329     }
 330   }
 331 }
 332 
 333 //=============================================================================
 334 void Parse::do_anewarray() {
 335   bool will_link;
 336   ciKlass* klass = iter().get_klass(will_link);
 337 
 338   // Uncommon Trap when class that array contains is not loaded
 339   // we need the loaded class for the rest of graph; do not
 340   // initialize the container class (see Java spec)!!!
 341   assert(will_link, "anewarray: typeflow responsibility");
 342 
 343   ciObjArrayKlass* array_klass = ciObjArrayKlass::make(klass);
 344   // Check that array_klass object is loaded
 345   if (!array_klass->is_loaded()) {
 346     // Generate uncommon_trap for unloaded array_class
 347     uncommon_trap(Deoptimization::Reason_unloaded,
 348                   Deoptimization::Action_reinterpret,
 349                   array_klass);
 350     return;
 351   }
 352 
 353   kill_dead_locals();
 354 
 355   const TypeKlassPtr* array_klass_type = TypeKlassPtr::make(array_klass);
 356   Node* count_val = pop();
 357   Node* obj = new_array(makecon(array_klass_type), count_val, 1);
 358   push(obj);
 359 }
 360 
 361 
 362 void Parse::do_newarray(BasicType elem_type) {
 363   kill_dead_locals();
 364 
 365   Node*   count_val = pop();
 366   const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(elem_type));
 367   Node*   obj = new_array(makecon(array_klass), count_val, 1);
 368   // Push resultant oop onto stack
 369   push(obj);
 370 }
 371 
 372 // Expand simple expressions like new int[3][5] and new Object[2][nonConLen].
 373 // Also handle the degenerate 1-dimensional case of anewarray.
 374 Node* Parse::expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs) {
 375   Node* length = lengths[0];
 376   assert(length != NULL, "");
 377   Node* array = new_array(makecon(TypeKlassPtr::make(array_klass)), length, nargs);
 378   if (ndimensions > 1) {
 379     jint length_con = find_int_con(length, -1);
 380     guarantee(length_con >= 0, "non-constant multianewarray");
 381     ciArrayKlass* array_klass_1 = array_klass->as_obj_array_klass()->element_klass()->as_array_klass();
 382     const TypePtr* adr_type = TypeAryPtr::OOPS;
 383     const TypeOopPtr*    elemtype = _gvn.type(array)->is_aryptr()->elem()->make_oopptr();
 384     const intptr_t header   = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
 385     for (jint i = 0; i < length_con; i++) {
 386       Node*    elem   = expand_multianewarray(array_klass_1, &lengths[1], ndimensions-1, nargs);
 387       intptr_t offset = header + ((intptr_t)i << LogBytesPerHeapOop);
 388       Node*    eaddr  = basic_plus_adr(array, offset);
 389       store_oop_to_array(control(), array, eaddr, adr_type, elem, elemtype, T_OBJECT, MemNode::unordered);
 390     }
 391   }
 392   return array;
 393 }
 394 
 395 void Parse::do_multianewarray() {
 396   int ndimensions = iter().get_dimensions();
 397 
 398   // the m-dimensional array
 399   bool will_link;
 400   ciArrayKlass* array_klass = iter().get_klass(will_link)->as_array_klass();
 401   assert(will_link, "multianewarray: typeflow responsibility");
 402 
 403   // Note:  Array classes are always initialized; no is_initialized check.
 404 
 405   kill_dead_locals();
 406 
 407   // get the lengths from the stack (first dimension is on top)
 408   Node** length = NEW_RESOURCE_ARRAY(Node*, ndimensions + 1);
 409   length[ndimensions] = NULL;  // terminating null for make_runtime_call
 410   int j;
 411   for (j = ndimensions-1; j >= 0 ; j--) length[j] = pop();
 412 
 413   // The original expression was of this form: new T[length0][length1]...
 414   // It is often the case that the lengths are small (except the last).
 415   // If that happens, use the fast 1-d creator a constant number of times.
 416   const jint expand_limit = MIN2((juint)MultiArrayExpandLimit, (juint)100);
 417   jint expand_count = 1;        // count of allocations in the expansion
 418   jint expand_fanout = 1;       // running total fanout
 419   for (j = 0; j < ndimensions-1; j++) {
 420     jint dim_con = find_int_con(length[j], -1);
 421     expand_fanout *= dim_con;
 422     expand_count  += expand_fanout; // count the level-J sub-arrays
 423     if (dim_con <= 0
 424         || dim_con > expand_limit
 425         || expand_count > expand_limit) {
 426       expand_count = 0;
 427       break;
 428     }
 429   }
 430 
 431   // Can use multianewarray instead of [a]newarray if only one dimension,
 432   // or if all non-final dimensions are small constants.
 433   if (ndimensions == 1 || (1 <= expand_count && expand_count <= expand_limit)) {
 434     Node* obj = NULL;
 435     // Set the original stack and the reexecute bit for the interpreter
 436     // to reexecute the multianewarray bytecode if deoptimization happens.
 437     // Do it unconditionally even for one dimension multianewarray.
 438     // Note: the reexecute bit will be set in GraphKit::add_safepoint_edges()
 439     // when AllocateArray node for newarray is created.
 440     { PreserveReexecuteState preexecs(this);
 441       inc_sp(ndimensions);
 442       // Pass 0 as nargs since uncommon trap code does not need to restore stack.
 443       obj = expand_multianewarray(array_klass, &length[0], ndimensions, 0);
 444     } //original reexecute and sp are set back here
 445     push(obj);
 446     return;
 447   }
 448 
 449   address fun = NULL;
 450   switch (ndimensions) {
 451   case 1: ShouldNotReachHere(); break;
 452   case 2: fun = OptoRuntime::multianewarray2_Java(); break;
 453   case 3: fun = OptoRuntime::multianewarray3_Java(); break;
 454   case 4: fun = OptoRuntime::multianewarray4_Java(); break;
 455   case 5: fun = OptoRuntime::multianewarray5_Java(); break;
 456   };
 457   Node* c = NULL;
 458 
 459   if (fun != NULL) {
 460     c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
 461                           OptoRuntime::multianewarray_Type(ndimensions),
 462                           fun, NULL, TypeRawPtr::BOTTOM,
 463                           makecon(TypeKlassPtr::make(array_klass)),
 464                           length[0], length[1], length[2],
 465                           (ndimensions > 2) ? length[3] : NULL,
 466                           (ndimensions > 3) ? length[4] : NULL);
 467   } else {
 468     // Create a java array for dimension sizes
 469     Node* dims = NULL;
 470     { PreserveReexecuteState preexecs(this);
 471       inc_sp(ndimensions);
 472       Node* dims_array_klass = makecon(TypeKlassPtr::make(ciArrayKlass::make(ciType::make(T_INT))));
 473       dims = new_array(dims_array_klass, intcon(ndimensions), 0);
 474 
 475       // Fill-in it with values
 476       for (j = 0; j < ndimensions; j++) {
 477         Node *dims_elem = array_element_address(dims, intcon(j), T_INT);
 478         store_to_memory(control(), dims_elem, length[j], T_INT, TypeAryPtr::INTS, MemNode::unordered);
 479       }
 480     }
 481 
 482     c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
 483                           OptoRuntime::multianewarrayN_Type(),
 484                           OptoRuntime::multianewarrayN_Java(), NULL, TypeRawPtr::BOTTOM,
 485                           makecon(TypeKlassPtr::make(array_klass)),
 486                           dims);
 487   }
 488   make_slow_call_ex(c, env()->Throwable_klass(), false);
 489 
 490   Node* res = _gvn.transform(new ProjNode(c, TypeFunc::Parms));
 491 
 492   const Type* type = TypeOopPtr::make_from_klass_raw(array_klass);
 493 
 494   // Improve the type:  We know it's not null, exact, and of a given length.
 495   type = type->is_ptr()->cast_to_ptr_type(TypePtr::NotNull);
 496   type = type->is_aryptr()->cast_to_exactness(true);
 497 
 498   const TypeInt* ltype = _gvn.find_int_type(length[0]);
 499   if (ltype != NULL)
 500     type = type->is_aryptr()->cast_to_size(ltype);
 501 
 502     // We cannot sharpen the nested sub-arrays, since the top level is mutable.
 503 
 504   Node* cast = _gvn.transform( new CheckCastPPNode(control(), res, type) );
 505   push(cast);
 506 
 507   // Possible improvements:
 508   // - Make a fast path for small multi-arrays.  (W/ implicit init. loops.)
 509   // - Issue CastII against length[*] values, to TypeInt::POS.
 510 }
--- EOF ---