1 /*
   2  * Copyright (c) 2008, 2011, 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 #ifndef SHARE_VM_PRIMS_METHODHANDLEWALK_HPP
  26 #define SHARE_VM_PRIMS_METHODHANDLEWALK_HPP
  27 
  28 #include "prims/methodHandles.hpp"
  29 
  30 // Low-level parser for method handle chains.
  31 class MethodHandleChain : StackObj {
  32 public:
  33   typedef MethodHandles::EntryKind EntryKind;
  34 
  35 private:
  36   Handle        _root;          // original target
  37   Handle        _method_handle; // current target
  38   bool          _is_last;       // final guy in chain
  39   bool          _is_bound;      // has a bound argument
  40   BasicType     _arg_type;      // if is_bound, the bound argument type
  41   int           _arg_slot;      // if is_bound or is_adapter, affected argument slot
  42   jint          _conversion;    // conversion field of AMH or -1
  43   methodHandle  _last_method;   // if is_last, which method we target
  44   Bytecodes::Code _last_invoke; // if is_last, type of invoke
  45   const char*   _lose_message;  // saved argument to lose()
  46 
  47   void set_method_handle(Handle target, TRAPS);
  48   void set_last_method(oop target, TRAPS);
  49   static BasicType compute_bound_arg_type(oop target, methodOop m, int arg_slot, TRAPS);
  50 
  51   oop MethodHandle_type_oop()          { return java_lang_invoke_MethodHandle::type(method_handle_oop()); }
  52   oop MethodHandle_vmtarget_oop()      { return java_lang_invoke_MethodHandle::vmtarget(method_handle_oop()); }
  53   int MethodHandle_vmslots()           { return java_lang_invoke_MethodHandle::vmslots(method_handle_oop()); }
  54   int DirectMethodHandle_vmindex()     { return java_lang_invoke_DirectMethodHandle::vmindex(method_handle_oop()); }
  55   oop BoundMethodHandle_argument_oop() { return java_lang_invoke_BoundMethodHandle::argument(method_handle_oop()); }
  56   int BoundMethodHandle_vmargslot()    { return java_lang_invoke_BoundMethodHandle::vmargslot(method_handle_oop()); }
  57   int AdapterMethodHandle_conversion() { return java_lang_invoke_AdapterMethodHandle::conversion(method_handle_oop()); }
  58 
  59 #ifdef ASSERT
  60   void print_impl(TRAPS);
  61 #endif
  62 
  63 public:
  64   MethodHandleChain(Handle root, TRAPS)
  65     : _root(root)
  66   { set_method_handle(root, THREAD); }
  67 
  68   bool is_adapter()             { return _conversion != -1; }
  69   bool is_bound()               { return _is_bound; }
  70   bool is_last()                { return _is_last; }
  71 
  72   void next(TRAPS) {
  73     assert(!is_last(), "");
  74     set_method_handle(MethodHandle_vmtarget_oop(), THREAD);
  75   }
  76 
  77   Handle method_handle()        { return _method_handle; }
  78   oop    method_handle_oop()    { return _method_handle(); }
  79   oop    method_type_oop()      { return MethodHandle_type_oop(); }
  80   oop    vmtarget_oop()         { return MethodHandle_vmtarget_oop(); }
  81 
  82   jint adapter_conversion()     { assert(is_adapter(), ""); return _conversion; }
  83   int  adapter_conversion_op()  { return MethodHandles::adapter_conversion_op(adapter_conversion()); }
  84   BasicType adapter_conversion_src_type()
  85                                 { return MethodHandles::adapter_conversion_src_type(adapter_conversion()); }
  86   BasicType adapter_conversion_dest_type()
  87                                 { return MethodHandles::adapter_conversion_dest_type(adapter_conversion()); }
  88   int  adapter_conversion_stack_move()
  89                                 { return MethodHandles::adapter_conversion_stack_move(adapter_conversion()); }
  90   int  adapter_conversion_stack_pushes()
  91                                 { return adapter_conversion_stack_move() / MethodHandles::stack_move_unit(); }
  92   int  adapter_conversion_vminfo()
  93                                 { return MethodHandles::adapter_conversion_vminfo(adapter_conversion()); }
  94   int adapter_arg_slot()        { assert(is_adapter(), ""); return _arg_slot; }
  95   oop adapter_arg_oop()         { assert(is_adapter(), ""); return BoundMethodHandle_argument_oop(); }
  96 
  97   BasicType bound_arg_type()    { assert(is_bound(), ""); return _arg_type; }
  98   int       bound_arg_slot()    { assert(is_bound(), ""); return _arg_slot; }
  99   oop       bound_arg_oop()     { assert(is_bound(), ""); return BoundMethodHandle_argument_oop(); }
 100 
 101   methodHandle last_method()    { assert(is_last(), ""); return _last_method; }
 102   methodOop last_method_oop()   { assert(is_last(), ""); return _last_method(); }
 103   Bytecodes::Code last_invoke_code() { assert(is_last(), ""); return _last_invoke; }
 104 
 105   void lose(const char* msg, TRAPS);
 106   const char* lose_message()    { return _lose_message; }
 107 
 108 #ifdef ASSERT
 109   // Print a symbolic description of a method handle chain, including
 110   // the signature for each method.  The signatures are printed in
 111   // slot order to make it easier to understand.
 112   void print();
 113   static void print(Handle mh);
 114   static void print(oopDesc* mh);
 115 #endif
 116 };
 117 
 118 
 119 // Structure walker for method handles.
 120 // Does abstract interpretation on top of low-level parsing.
 121 // You supply the tokens shuffled by the abstract interpretation.
 122 class MethodHandleWalker : StackObj {
 123 public:
 124   // Stack values:
 125   enum TokenType {
 126     tt_void,
 127     tt_parameter,
 128     tt_temporary,
 129     tt_constant,
 130     tt_symbolic,
 131     tt_illegal
 132   };
 133 
 134   // Argument token:
 135   class ArgToken {
 136   private:
 137     TokenType _tt;
 138     BasicType _bt;
 139     jvalue    _value;
 140     Handle    _handle;
 141 
 142   public:
 143     ArgToken(TokenType tt = tt_illegal) : _tt(tt), _bt(tt == tt_void ? T_VOID : T_ILLEGAL) {
 144       assert(tt == tt_illegal || tt == tt_void, "invalid token type");
 145     }
 146 
 147     ArgToken(TokenType tt, BasicType bt, int index) : _tt(tt), _bt(bt) {
 148       assert(_tt == tt_parameter || _tt == tt_temporary, "must have index");
 149       _value.i = index;
 150     }
 151 
 152     ArgToken(BasicType bt, jvalue value) : _tt(tt_constant), _bt(bt), _value(value) { assert(_bt != T_OBJECT, "wrong constructor"); }
 153     ArgToken(Handle handle) : _tt(tt_constant), _bt(T_OBJECT), _handle(handle) {}
 154 
 155 
 156     ArgToken(const char* str, BasicType type) : _tt(tt_symbolic), _bt(type) {
 157       _value.j = (intptr_t)str;
 158     }
 159 
 160     TokenType token_type()  const { return _tt; }
 161     BasicType basic_type()  const { return _bt; }
 162     bool      has_index()   const { return _tt == tt_parameter || _tt == tt_temporary; }
 163     int       index()       const { assert(has_index(), "must have index");; return _value.i; }
 164     Handle    object()      const { assert(_bt == T_OBJECT, "wrong accessor"); assert(_tt == tt_constant, "value type"); return _handle; }
 165     const char* str()       const { assert(_tt == tt_symbolic, "string type"); return (const char*)(intptr_t)_value.j; }
 166 
 167     jint      get_jint()    const { assert(_bt == T_INT || is_subword_type(_bt), "wrong accessor"); assert(_tt == tt_constant, "value types"); return _value.i; }
 168     jlong     get_jlong()   const { assert(_bt == T_LONG, "wrong accessor");   assert(_tt == tt_constant, "value types"); return _value.j; }
 169     jfloat    get_jfloat()  const { assert(_bt == T_FLOAT, "wrong accessor");  assert(_tt == tt_constant, "value types"); return _value.f; }
 170     jdouble   get_jdouble() const { assert(_bt == T_DOUBLE, "wrong accessor"); assert(_tt == tt_constant, "value types"); return _value.d; }
 171   };
 172 
 173 private:
 174   MethodHandleChain _chain;
 175   bool              _for_invokedynamic;
 176   int               _local_index;
 177 
 178   // This array is kept in an unusual order, indexed by low-level "slot number".
 179   // TOS is always _outgoing.at(0), so simple pushes and pops shift the whole _outgoing array.
 180   // If there is a receiver in the current argument list, it is at _outgoing.at(_outgoing.length()-1).
 181   // If a value at _outgoing.at(n) is T_LONG or T_DOUBLE, the value at _outgoing.at(n+1) is T_VOID.
 182   GrowableArray<ArgToken>  _outgoing;       // current outgoing parameter slots
 183   int                      _outgoing_argc;  // # non-empty outgoing slots
 184 
 185   vmIntrinsics::ID _return_conv;            // Return conversion required by raw retypes.
 186 
 187   // Replace a value of type old_type at slot (and maybe slot+1) with the new value.
 188   // If old_type != T_VOID, remove the old argument at that point.
 189   // If new_type != T_VOID, insert the new argument at that point.
 190   // Insert or delete a second empty slot as needed.
 191   void change_argument(BasicType old_type, int slot, const ArgToken& new_arg);
 192   void change_argument(BasicType old_type, int slot, BasicType type, const ArgToken& new_arg) {
 193     assert(type == new_arg.basic_type(), "must agree");
 194     change_argument(old_type, slot, new_arg);
 195   }
 196 
 197   // Raw retype conversions for OP_RAW_RETYPE.
 198   void retype_raw_conversion(BasicType src, BasicType dst, bool for_return, int slot, TRAPS);
 199   void retype_raw_argument_type(BasicType src, BasicType dst, int slot, TRAPS) { retype_raw_conversion(src, dst, false, slot, CHECK); }
 200   void retype_raw_return_type(  BasicType src, BasicType dst,           TRAPS) { retype_raw_conversion(src, dst, true,  -1,   CHECK); }
 201 
 202   BasicType arg_type(int slot) {
 203     return _outgoing.at(slot).basic_type();
 204   }
 205   bool has_argument(int slot) {
 206     return arg_type(slot) < T_VOID;
 207   }
 208 
 209 #ifdef ASSERT
 210   int argument_count_slow();
 211 #endif
 212 
 213   // Return a bytecode for converting src to dest, if one exists.
 214   Bytecodes::Code conversion_code(BasicType src, BasicType dest);
 215 
 216   void walk_incoming_state(TRAPS);
 217 
 218   void verify_args_and_signature(TRAPS) NOT_DEBUG_RETURN;
 219 
 220 public:
 221   MethodHandleWalker(Handle root, bool for_invokedynamic, TRAPS)
 222     : _chain(root, THREAD),
 223       _for_invokedynamic(for_invokedynamic),
 224       _outgoing(THREAD, 10),
 225       _outgoing_argc(0),
 226       _return_conv(vmIntrinsics::_none)
 227   {
 228     _local_index = for_invokedynamic ? 0 : 1;
 229   }
 230 
 231   MethodHandleChain& chain() { return _chain; }
 232 
 233   bool for_invokedynamic() const { return _for_invokedynamic; }
 234 
 235   vmIntrinsics::ID return_conv() const { return _return_conv; }
 236   void set_return_conv(vmIntrinsics::ID c) { _return_conv = c; }
 237   static vmIntrinsics::ID zero_return_conv() { return vmIntrinsics::_min; }
 238 
 239   int new_local_index(BasicType bt) {
 240     //int index = _for_invokedynamic ? _local_index : _local_index - 1;
 241     int index = _local_index;
 242     _local_index += type2size[bt];
 243     return index;
 244   }
 245 
 246   int max_locals() const { return _local_index; }
 247 
 248   // plug-in abstract interpretation steps:
 249   virtual ArgToken make_parameter(BasicType type, klassOop tk, int argnum, TRAPS) = 0;
 250   virtual ArgToken make_prim_constant(BasicType type, jvalue* con, TRAPS) = 0;
 251   virtual ArgToken make_oop_constant(oop con, TRAPS) = 0;
 252   virtual ArgToken make_conversion(BasicType type, klassOop tk, Bytecodes::Code op, const ArgToken& src, TRAPS) = 0;
 253   virtual ArgToken make_fetch(BasicType type, klassOop tk, Bytecodes::Code op, const ArgToken& base, const ArgToken& offset, TRAPS) = 0;
 254   virtual ArgToken make_invoke(methodHandle m, vmIntrinsics::ID iid, Bytecodes::Code op, bool tailcall, int argc, ArgToken* argv, TRAPS) = 0;
 255 
 256   // For make_invoke, the methodHandle can be NULL if the intrinsic ID
 257   // is something other than vmIntrinsics::_none.
 258 
 259   // and in case anyone cares to related the previous actions to the chain:
 260   virtual void set_method_handle(oop mh) { }
 261 
 262   void lose(const char* msg, TRAPS) { chain().lose(msg, THREAD); }
 263   const char* lose_message()        { return chain().lose_message(); }
 264 
 265   ArgToken walk(TRAPS);
 266 };
 267 
 268 
 269 // An abstract interpreter for method handle chains.
 270 // Produces an account of the semantics of a chain, in terms of a static IR.
 271 // The IR happens to be JVM bytecodes.
 272 class MethodHandleCompiler : public MethodHandleWalker {
 273 private:
 274   int          _invoke_count;  // count the original call site has been executed
 275   KlassHandle  _rklass;        // Return type for casting.
 276   BasicType    _rtype;
 277   KlassHandle  _target_klass;
 278   Thread*      _thread;
 279 
 280   // Values used by the compiler.
 281   static jvalue zero_jvalue;
 282   static jvalue one_jvalue;
 283 
 284   // Fake constant pool entry.
 285   class ConstantValue : public ResourceObj {
 286   private:
 287     int       _tag;   // Constant pool tag type.
 288     JavaValue _value;
 289     Handle    _handle;
 290     Symbol*   _sym;
 291     methodHandle _method;  // pre-linkage
 292 
 293   public:
 294     // Constructor for oop types.
 295     ConstantValue(int tag, Handle con) : _tag(tag), _handle(con) {
 296       assert(tag == JVM_CONSTANT_Class  ||
 297              tag == JVM_CONSTANT_String ||
 298              tag == JVM_CONSTANT_Object, "must be oop type");
 299     }
 300 
 301     ConstantValue(int tag, Symbol* con) : _tag(tag), _sym(con) {
 302       assert(tag == JVM_CONSTANT_Utf8, "must be symbol type");
 303     }
 304 
 305     // Constructor for oop reference types.
 306     ConstantValue(int tag, int index) : _tag(tag) {
 307       assert(JVM_CONSTANT_Fieldref <= tag && tag <= JVM_CONSTANT_NameAndType, "must be ref type");
 308       _value.set_jint(index);
 309     }
 310     ConstantValue(int tag, int first_index, int second_index) : _tag(tag) {
 311       assert(JVM_CONSTANT_Fieldref <= tag && tag <= JVM_CONSTANT_NameAndType, "must be ref type");
 312       _value.set_jint(first_index << 16 | second_index);
 313     }
 314 
 315     // Constructor for primitive types.
 316     ConstantValue(BasicType bt, jvalue con) {
 317       _value.set_type(bt);
 318       switch (bt) {
 319       case T_INT:    _tag = JVM_CONSTANT_Integer; _value.set_jint(   con.i); break;
 320       case T_LONG:   _tag = JVM_CONSTANT_Long;    _value.set_jlong(  con.j); break;
 321       case T_FLOAT:  _tag = JVM_CONSTANT_Float;   _value.set_jfloat( con.f); break;
 322       case T_DOUBLE: _tag = JVM_CONSTANT_Double;  _value.set_jdouble(con.d); break;
 323       default: ShouldNotReachHere();
 324       }
 325     }
 326 
 327     int       tag()          const { return _tag; }
 328     Symbol*   symbol()       const { return _sym; }
 329     klassOop  klass_oop()    const { return (klassOop)  _handle(); }
 330     oop       object_oop()   const { return _handle(); }
 331     int       index()        const { return _value.get_jint(); }
 332     int       first_index()  const { return _value.get_jint() >> 16; }
 333     int       second_index() const { return _value.get_jint() & 0x0000FFFF; }
 334 
 335     bool      is_primitive() const { return is_java_primitive(_value.get_type()); }
 336     jint      get_jint()     const { return _value.get_jint();    }
 337     jlong     get_jlong()    const { return _value.get_jlong();   }
 338     jfloat    get_jfloat()   const { return _value.get_jfloat();  }
 339     jdouble   get_jdouble()  const { return _value.get_jdouble(); }
 340 
 341     void set_linkage(methodHandle method) {
 342       assert(_method.is_null(), "");
 343       _method = method;
 344     }
 345     bool     has_linkage()   const { return _method.not_null(); }
 346     methodHandle linkage()   const { return _method; }
 347   };
 348 
 349   // Fake constant pool.
 350   GrowableArray<ConstantValue*> _constants;
 351 
 352   // Non-BCP classes that appear in associated MethodTypes (require special handling).
 353   GrowableArray<KlassHandle> _non_bcp_klasses;
 354 
 355   // Accumulated compiler state:
 356   GrowableArray<unsigned char> _bytecode;
 357 
 358   int _cur_stack;
 359   int _max_stack;
 360   int _num_params;
 361   int _name_index;
 362   int _signature_index;
 363 
 364   void stack_push(BasicType bt) {
 365     _cur_stack += type2size[bt];
 366     if (_cur_stack > _max_stack) _max_stack = _cur_stack;
 367   }
 368   void stack_pop(BasicType bt) {
 369     _cur_stack -= type2size[bt];
 370     assert(_cur_stack >= 0, "sanity");
 371   }
 372 
 373   unsigned char* bytecode()        const { return _bytecode.adr_at(0); }
 374   int            bytecode_length() const { return _bytecode.length(); }
 375 
 376   // Fake constant pool.
 377   int cpool_oop_put(int tag, Handle con) {
 378     if (con.is_null())  return 0;
 379     ConstantValue* cv = new ConstantValue(tag, con);
 380     return _constants.append(cv);
 381   }
 382 
 383   int cpool_symbol_put(int tag, Symbol* con) {
 384     if (con == NULL)  return 0;
 385     ConstantValue* cv = new ConstantValue(tag, con);
 386     con->increment_refcount();
 387     return _constants.append(cv);
 388   }
 389 
 390   int cpool_oop_reference_put(int tag, int first_index, int second_index, methodHandle method) {
 391     if (first_index == 0 && second_index == 0)  return 0;
 392     assert(first_index != 0 && second_index != 0, "no zero indexes");
 393     ConstantValue* cv = new ConstantValue(tag, first_index, second_index);
 394     if (method.not_null())  cv->set_linkage(method);
 395     return _constants.append(cv);
 396   }
 397 
 398   int cpool_primitive_put(BasicType type, jvalue* con);
 399 
 400   bool check_non_bcp_klasses(Handle method_type, TRAPS);
 401   bool check_non_bcp_klass(klassOop klass, TRAPS);
 402   void record_non_bcp_klasses();
 403 
 404   int cpool_int_put(jint value) {
 405     jvalue con; con.i = value;
 406     return cpool_primitive_put(T_INT, &con);
 407   }
 408   int cpool_long_put(jlong value) {
 409     jvalue con; con.j = value;
 410     return cpool_primitive_put(T_LONG, &con);
 411   }
 412   int cpool_float_put(jfloat value) {
 413     jvalue con; con.f = value;
 414     return cpool_primitive_put(T_FLOAT, &con);
 415   }
 416   int cpool_double_put(jdouble value) {
 417     jvalue con; con.d = value;
 418     return cpool_primitive_put(T_DOUBLE, &con);
 419   }
 420 
 421   int cpool_object_put(Handle obj) {
 422     return cpool_oop_put(JVM_CONSTANT_Object, obj);
 423   }
 424   int cpool_symbol_put(Symbol* sym) {
 425     return cpool_symbol_put(JVM_CONSTANT_Utf8, sym);
 426   }
 427   int cpool_klass_put(klassOop klass) {
 428     return cpool_oop_put(JVM_CONSTANT_Class, klass);
 429   }
 430   int cpool_methodref_put(Bytecodes::Code op, int class_index, int name_and_type_index, methodHandle method) {
 431     int tag = (op == Bytecodes::_invokeinterface ? JVM_CONSTANT_InterfaceMethodref : JVM_CONSTANT_Methodref);
 432     return cpool_oop_reference_put(tag, class_index, name_and_type_index, method);
 433   }
 434   int cpool_name_and_type_put(int name_index, int signature_index) {
 435     return cpool_oop_reference_put(JVM_CONSTANT_NameAndType, name_index, signature_index, methodHandle());
 436   }
 437 
 438   void emit_bc(Bytecodes::Code op, int index = 0, int args_size = -1);
 439   void emit_load(BasicType bt, int index);
 440   void emit_store(BasicType bt, int index);
 441   void emit_load_constant(ArgToken arg);
 442 
 443   virtual ArgToken make_parameter(BasicType type, klassOop tk, int argnum, TRAPS) {
 444     return ArgToken(tt_parameter, type, argnum);
 445   }
 446   virtual ArgToken make_oop_constant(oop con, TRAPS) {
 447     Handle h(THREAD, con);
 448     return ArgToken(h);
 449   }
 450   virtual ArgToken make_prim_constant(BasicType type, jvalue* con, TRAPS) {
 451     return ArgToken(type, *con);
 452   }
 453 
 454   virtual ArgToken make_conversion(BasicType type, klassOop tk, Bytecodes::Code op, const ArgToken& src, TRAPS);
 455   virtual ArgToken make_fetch(BasicType type, klassOop tk, Bytecodes::Code op, const ArgToken& base, const ArgToken& offset, TRAPS);
 456   virtual ArgToken make_invoke(methodHandle m, vmIntrinsics::ID iid, Bytecodes::Code op, bool tailcall, int argc, ArgToken* argv, TRAPS);
 457 
 458   // Get a real constant pool.
 459   constantPoolHandle get_constant_pool(TRAPS) const;
 460 
 461   // Get a real methodOop.
 462   methodHandle get_method_oop(TRAPS) const;
 463 
 464 public:
 465   MethodHandleCompiler(Handle root, Symbol* name, Symbol* signature, int invoke_count, bool for_invokedynamic, TRAPS);
 466 
 467   // Compile the given MH chain into bytecode.
 468   methodHandle compile(TRAPS);
 469 
 470   // Tests if the given class is a MH adapter holder.
 471   static bool klass_is_method_handle_adapter_holder(klassOop klass) {
 472     return (klass == SystemDictionary::MethodHandle_klass());
 473   }
 474 };
 475 
 476 #endif // SHARE_VM_PRIMS_METHODHANDLEWALK_HPP