1 /*
   2  * Copyright (c) 1998, 2018, 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.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 void Parse::do_field_access(bool is_get, bool is_field) {
  44   bool will_link;
  45   ciField* field = iter().get_field(will_link);
  46   assert(will_link, "getfield: typeflow responsibility");
  47 
  48   ciInstanceKlass* field_holder = field->holder();
  49 
  50   if (is_field == field->is_static()) {
  51     // Interpreter will throw java_lang_IncompatibleClassChangeError
  52     // Check this before allowing <clinit> methods to access static fields
  53     uncommon_trap(Deoptimization::Reason_unhandled,
  54                   Deoptimization::Action_none);
  55     return;
  56   }
  57 
  58   // Deoptimize on putfield writes to call site target field.
  59   if (!is_get && field->is_call_site_target()) {
  60     uncommon_trap(Deoptimization::Reason_unhandled,
  61                   Deoptimization::Action_reinterpret,
  62                   NULL, "put to call site target field");
  63     return;
  64   }
  65 
  66   if (C->needs_clinit_barrier(field, method())) {
  67     clinit_barrier(field_holder, method());
  68     if (stopped())  return;
  69   }
  70 
  71   assert(field->will_link(method(), bc()), "getfield: typeflow responsibility");
  72 
  73   // Note:  We do not check for an unloaded field type here any more.
  74 
  75   // Generate code for the object pointer.
  76   Node* obj;
  77   if (is_field) {
  78     int obj_depth = is_get ? 0 : field->type()->size();
  79     obj = null_check(peek(obj_depth));
  80     // Compile-time detect of null-exception?
  81     if (stopped())  return;
  82 
  83 #ifdef ASSERT
  84     const TypeInstPtr *tjp = TypeInstPtr::make(TypePtr::NotNull, iter().get_declared_field_holder());
  85     assert(_gvn.type(obj)->higher_equal(tjp), "cast_up is no longer needed");
  86 #endif
  87 
  88     if (is_get) {
  89       (void) pop();  // pop receiver before getting
  90       do_get_xxx(obj, field, is_field);
  91     } else {
  92       do_put_xxx(obj, field, is_field);
  93       (void) pop();  // pop receiver after putting
  94     }
  95   } else {
  96     const TypeInstPtr* tip = TypeInstPtr::make(field_holder->java_mirror());
  97     obj = _gvn.makecon(tip);
  98     if (is_get) {
  99       do_get_xxx(obj, field, is_field);
 100     } else {
 101       do_put_xxx(obj, field, is_field);
 102     }
 103   }
 104 }
 105 
 106 
 107 void Parse::do_get_xxx(Node* obj, ciField* field, bool is_field) {
 108   BasicType bt = field->layout_type();
 109 
 110   // Does this field have a constant value?  If so, just push the value.
 111   if (field->is_constant() &&
 112       // Keep consistent with types found by ciTypeFlow: for an
 113       // unloaded field type, ciTypeFlow::StateVector::do_getstatic()
 114       // speculates the field is null. The code in the rest of this
 115       // method does the same. We must not bypass it and use a non
 116       // null constant here.
 117       (bt != T_OBJECT || field->type()->is_loaded())) {
 118     // final or stable field
 119     Node* con = make_constant_from_field(field, obj);
 120     if (con != NULL) {
 121       push_node(field->layout_type(), con);
 122       return;
 123     }
 124   }
 125 
 126   ciType* field_klass = field->type();
 127   bool is_vol = field->is_volatile();
 128 
 129   // Compute address and memory type.
 130   int offset = field->offset_in_bytes();
 131   const TypePtr* adr_type = C->alias_type(field)->adr_type();
 132   Node *adr = basic_plus_adr(obj, obj, offset);
 133 
 134   // Build the resultant type of the load
 135   const Type *type;
 136 
 137   bool must_assert_null = false;
 138 
 139   DecoratorSet decorators = IN_HEAP;
 140   decorators |= is_vol ? MO_SEQ_CST : MO_UNORDERED;
 141 
 142   bool is_obj = bt == T_OBJECT || bt == T_ARRAY;
 143 
 144   if (is_obj) {
 145     if (!field->type()->is_loaded()) {
 146       type = TypeInstPtr::BOTTOM;
 147       must_assert_null = true;
 148     } else if (field->is_static_constant()) {
 149       // This can happen if the constant oop is non-perm.
 150       ciObject* con = field->constant_value().as_object();
 151       // Do not "join" in the previous type; it doesn't add value,
 152       // and may yield a vacuous result if the field is of interface type.
 153       if (con->is_null_object()) {
 154         type = TypePtr::NULL_PTR;
 155       } else {
 156         type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
 157       }
 158       assert(type != NULL, "field singleton type must be consistent");
 159     } else {
 160       type = TypeOopPtr::make_from_klass(field_klass->as_klass());
 161     }
 162   } else {
 163     type = Type::get_const_basic_type(bt);
 164   }
 165 
 166   Node* ld = access_load_at(obj, adr, adr_type, type, bt, decorators);
 167 
 168   // Adjust Java stack
 169   if (type2size[bt] == 1)
 170     push(ld);
 171   else
 172     push_pair(ld);
 173 
 174   if (must_assert_null) {
 175     // Do not take a trap here.  It's possible that the program
 176     // will never load the field's class, and will happily see
 177     // null values in this field forever.  Don't stumble into a
 178     // trap for such a program, or we might get a long series
 179     // of useless recompilations.  (Or, we might load a class
 180     // which should not be loaded.)  If we ever see a non-null
 181     // value, we will then trap and recompile.  (The trap will
 182     // not need to mention the class index, since the class will
 183     // already have been loaded if we ever see a non-null value.)
 184     // uncommon_trap(iter().get_field_signature_index());
 185     if (PrintOpto && (Verbose || WizardMode)) {
 186       method()->print_name(); tty->print_cr(" asserting nullness of field at bci: %d", bci());
 187     }
 188     if (C->log() != NULL) {
 189       C->log()->elem("assert_null reason='field' klass='%d'",
 190                      C->log()->identify(field->type()));
 191     }
 192     // If there is going to be a trap, put it at the next bytecode:
 193     set_bci(iter().next_bci());
 194     null_assert(peek());
 195     set_bci(iter().cur_bci()); // put it back
 196   }
 197 }
 198 
 199 void Parse::do_put_xxx(Node* obj, ciField* field, bool is_field) {
 200   bool is_vol = field->is_volatile();
 201 
 202   // Compute address and memory type.
 203   int offset = field->offset_in_bytes();
 204   const TypePtr* adr_type = C->alias_type(field)->adr_type();
 205   Node* adr = basic_plus_adr(obj, obj, offset);
 206   BasicType bt = field->layout_type();
 207   // Value to be stored
 208   Node* val = type2size[bt] == 1 ? pop() : pop_pair();
 209 
 210   DecoratorSet decorators = IN_HEAP;
 211   decorators |= is_vol ? MO_SEQ_CST : MO_UNORDERED;
 212 
 213   bool is_obj = bt == T_OBJECT || bt == T_ARRAY;
 214 
 215   // Store the value.
 216   const Type* field_type;
 217   if (!field->type()->is_loaded()) {
 218     field_type = TypeInstPtr::BOTTOM;
 219   } else {
 220     if (is_obj) {
 221       field_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
 222     } else {
 223       field_type = Type::BOTTOM;
 224     }
 225   }
 226   access_store_at(obj, adr, adr_type, val, field_type, bt, decorators);
 227 
 228   if (is_field) {
 229     // Remember we wrote a volatile field.
 230     // For not multiple copy atomic cpu (ppc64) a barrier should be issued
 231     // in constructors which have such stores. See do_exits() in parse1.cpp.
 232     if (is_vol) {
 233       set_wrote_volatile(true);
 234     }
 235     set_wrote_fields(true);
 236 
 237     // If the field is final, the rules of Java say we are in <init> or <clinit>.
 238     // Note the presence of writes to final non-static fields, so that we
 239     // can insert a memory barrier later on to keep the writes from floating
 240     // out of the constructor.
 241     // Any method can write a @Stable field; insert memory barriers after those also.
 242     if (field->is_final()) {
 243       set_wrote_final(true);
 244       if (AllocateNode::Ideal_allocation(obj, &_gvn) != NULL) {
 245         // Preserve allocation ptr to create precedent edge to it in membar
 246         // generated on exit from constructor.
 247         // Can't bind stable with its allocation, only record allocation for final field.
 248         set_alloc_with_final(obj);
 249       }
 250     }
 251     if (field->is_stable()) {
 252       set_wrote_stable(true);
 253     }
 254   }
 255 }
 256 
 257 //=============================================================================
 258 void Parse::do_anewarray() {
 259   bool will_link;
 260   ciKlass* klass = iter().get_klass(will_link);
 261 
 262   // Uncommon Trap when class that array contains is not loaded
 263   // we need the loaded class for the rest of graph; do not
 264   // initialize the container class (see Java spec)!!!
 265   assert(will_link, "anewarray: typeflow responsibility");
 266 
 267   ciObjArrayKlass* array_klass = ciObjArrayKlass::make(klass);
 268   // Check that array_klass object is loaded
 269   if (!array_klass->is_loaded()) {
 270     // Generate uncommon_trap for unloaded array_class
 271     uncommon_trap(Deoptimization::Reason_unloaded,
 272                   Deoptimization::Action_reinterpret,
 273                   array_klass);
 274     return;
 275   }
 276 
 277   kill_dead_locals();
 278 
 279   const TypeKlassPtr* array_klass_type = TypeKlassPtr::make(array_klass);
 280   Node* count_val = pop();
 281   Node* obj = new_array(makecon(array_klass_type), count_val, 1);
 282   push(obj);
 283 }
 284 
 285 
 286 void Parse::do_newarray(BasicType elem_type) {
 287   kill_dead_locals();
 288 
 289   Node*   count_val = pop();
 290   const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(elem_type));
 291   Node*   obj = new_array(makecon(array_klass), count_val, 1);
 292   // Push resultant oop onto stack
 293   push(obj);
 294 }
 295 
 296 // Expand simple expressions like new int[3][5] and new Object[2][nonConLen].
 297 // Also handle the degenerate 1-dimensional case of anewarray.
 298 Node* Parse::expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs) {
 299   Node* length = lengths[0];
 300   assert(length != NULL, "");
 301   Node* array = new_array(makecon(TypeKlassPtr::make(array_klass)), length, nargs);
 302   if (ndimensions > 1) {
 303     jint length_con = find_int_con(length, -1);
 304     guarantee(length_con >= 0, "non-constant multianewarray");
 305     ciArrayKlass* array_klass_1 = array_klass->as_obj_array_klass()->element_klass()->as_array_klass();
 306     const TypePtr* adr_type = TypeAryPtr::OOPS;
 307     const TypeOopPtr*    elemtype = _gvn.type(array)->is_aryptr()->elem()->make_oopptr();
 308     const intptr_t header   = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
 309     for (jint i = 0; i < length_con; i++) {
 310       Node*    elem   = expand_multianewarray(array_klass_1, &lengths[1], ndimensions-1, nargs);
 311       intptr_t offset = header + ((intptr_t)i << LogBytesPerHeapOop);
 312       Node*    eaddr  = basic_plus_adr(array, offset);
 313       access_store_at(array, eaddr, adr_type, elem, elemtype, T_OBJECT, IN_HEAP | IS_ARRAY);
 314     }
 315   }
 316   return array;
 317 }
 318 
 319 void Parse::do_multianewarray() {
 320   int ndimensions = iter().get_dimensions();
 321 
 322   // the m-dimensional array
 323   bool will_link;
 324   ciArrayKlass* array_klass = iter().get_klass(will_link)->as_array_klass();
 325   assert(will_link, "multianewarray: typeflow responsibility");
 326 
 327   // Note:  Array classes are always initialized; no is_initialized check.
 328 
 329   kill_dead_locals();
 330 
 331   // get the lengths from the stack (first dimension is on top)
 332   Node** length = NEW_RESOURCE_ARRAY(Node*, ndimensions + 1);
 333   length[ndimensions] = NULL;  // terminating null for make_runtime_call
 334   int j;
 335   for (j = ndimensions-1; j >= 0 ; j--) length[j] = pop();
 336 
 337   // The original expression was of this form: new T[length0][length1]...
 338   // It is often the case that the lengths are small (except the last).
 339   // If that happens, use the fast 1-d creator a constant number of times.
 340   const int expand_limit = MIN2((int)MultiArrayExpandLimit, 100);
 341   int expand_count = 1;        // count of allocations in the expansion
 342   int expand_fanout = 1;       // running total fanout
 343   for (j = 0; j < ndimensions-1; j++) {
 344     int dim_con = find_int_con(length[j], -1);
 345     expand_fanout *= dim_con;
 346     expand_count  += expand_fanout; // count the level-J sub-arrays
 347     if (dim_con <= 0
 348         || dim_con > expand_limit
 349         || expand_count > expand_limit) {
 350       expand_count = 0;
 351       break;
 352     }
 353   }
 354 
 355   // Can use multianewarray instead of [a]newarray if only one dimension,
 356   // or if all non-final dimensions are small constants.
 357   if (ndimensions == 1 || (1 <= expand_count && expand_count <= expand_limit)) {
 358     Node* obj = NULL;
 359     // Set the original stack and the reexecute bit for the interpreter
 360     // to reexecute the multianewarray bytecode if deoptimization happens.
 361     // Do it unconditionally even for one dimension multianewarray.
 362     // Note: the reexecute bit will be set in GraphKit::add_safepoint_edges()
 363     // when AllocateArray node for newarray is created.
 364     { PreserveReexecuteState preexecs(this);
 365       inc_sp(ndimensions);
 366       // Pass 0 as nargs since uncommon trap code does not need to restore stack.
 367       obj = expand_multianewarray(array_klass, &length[0], ndimensions, 0);
 368     } //original reexecute and sp are set back here
 369     push(obj);
 370     return;
 371   }
 372 
 373   address fun = NULL;
 374   switch (ndimensions) {
 375   case 1: ShouldNotReachHere(); break;
 376   case 2: fun = OptoRuntime::multianewarray2_Java(); break;
 377   case 3: fun = OptoRuntime::multianewarray3_Java(); break;
 378   case 4: fun = OptoRuntime::multianewarray4_Java(); break;
 379   case 5: fun = OptoRuntime::multianewarray5_Java(); break;
 380   };
 381   Node* c = NULL;
 382 
 383   if (fun != NULL) {
 384     c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
 385                           OptoRuntime::multianewarray_Type(ndimensions),
 386                           fun, NULL, TypeRawPtr::BOTTOM,
 387                           makecon(TypeKlassPtr::make(array_klass)),
 388                           length[0], length[1], length[2],
 389                           (ndimensions > 2) ? length[3] : NULL,
 390                           (ndimensions > 3) ? length[4] : NULL);
 391   } else {
 392     // Create a java array for dimension sizes
 393     Node* dims = NULL;
 394     { PreserveReexecuteState preexecs(this);
 395       inc_sp(ndimensions);
 396       Node* dims_array_klass = makecon(TypeKlassPtr::make(ciArrayKlass::make(ciType::make(T_INT))));
 397       dims = new_array(dims_array_klass, intcon(ndimensions), 0);
 398 
 399       // Fill-in it with values
 400       for (j = 0; j < ndimensions; j++) {
 401         Node *dims_elem = array_element_address(dims, intcon(j), T_INT);
 402         store_to_memory(control(), dims_elem, length[j], T_INT, TypeAryPtr::INTS, MemNode::unordered);
 403       }
 404     }
 405 
 406     c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
 407                           OptoRuntime::multianewarrayN_Type(),
 408                           OptoRuntime::multianewarrayN_Java(), NULL, TypeRawPtr::BOTTOM,
 409                           makecon(TypeKlassPtr::make(array_klass)),
 410                           dims);
 411   }
 412   make_slow_call_ex(c, env()->Throwable_klass(), false);
 413 
 414   Node* res = _gvn.transform(new ProjNode(c, TypeFunc::Parms));
 415 
 416   const Type* type = TypeOopPtr::make_from_klass_raw(array_klass);
 417 
 418   // Improve the type:  We know it's not null, exact, and of a given length.
 419   type = type->is_ptr()->cast_to_ptr_type(TypePtr::NotNull);
 420   type = type->is_aryptr()->cast_to_exactness(true);
 421 
 422   const TypeInt* ltype = _gvn.find_int_type(length[0]);
 423   if (ltype != NULL)
 424     type = type->is_aryptr()->cast_to_size(ltype);
 425 
 426     // We cannot sharpen the nested sub-arrays, since the top level is mutable.
 427 
 428   Node* cast = _gvn.transform( new CheckCastPPNode(control(), res, type) );
 429   push(cast);
 430 
 431   // Possible improvements:
 432   // - Make a fast path for small multi-arrays.  (W/ implicit init. loops.)
 433   // - Issue CastII against length[*] values, to TypeInt::POS.
 434 }