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   methodOop last_method_oop()   { assert(is_last(), ""); return _last_method(); }
 102   Bytecodes::Code last_invoke_code() { assert(is_last(), ""); return _last_invoke; }
 103 
 104   void lose(const char* msg, TRAPS);
 105   const char* lose_message()    { return _lose_message; }
 106 
 107 #ifdef ASSERT
 108   // Print a symbolic description of a method handle chain, including
 109   // the signature for each method.  The signatures are printed in
 110   // slot order to make it easier to understand.
 111   void print();
 112   static void print(Handle mh);
 113   static void print(oopDesc* mh);
 114 #endif
 115 };
 116 
 117 
 118 // Structure walker for method handles.
 119 // Does abstract interpretation on top of low-level parsing.
 120 // You supply the tokens shuffled by the abstract interpretation.
 121 class MethodHandleWalker : StackObj {
 122 public:
 123   // Stack values:
 124   enum TokenType {
 125     tt_void,
 126     tt_parameter,
 127     tt_temporary,
 128     tt_constant,
 129     tt_symbolic,
 130     tt_illegal
 131   };
 132 
 133   // Argument token:
 134   class ArgToken {
 135   private:
 136     TokenType _tt;
 137     BasicType _bt;
 138     jvalue    _value;
 139     Handle    _handle;
 140 
 141   public:
 142     ArgToken(TokenType tt = tt_illegal) : _tt(tt), _bt(tt == tt_void ? T_VOID : T_ILLEGAL) {
 143       assert(tt == tt_illegal || tt == tt_void, "invalid token type");
 144     }
 145 
 146     ArgToken(TokenType tt, BasicType bt, int index) : _tt(tt), _bt(bt) {
 147       assert(_tt == tt_parameter || _tt == tt_temporary, "must have index");
 148       _value.i = index;
 149     }
 150 
 151     ArgToken(BasicType bt, jvalue value) : _tt(tt_constant), _bt(bt), _value(value) { assert(_bt != T_OBJECT, "wrong constructor"); }
 152     ArgToken(Handle handle) : _tt(tt_constant), _bt(T_OBJECT), _handle(handle) {}
 153 
 154 
 155     ArgToken(const char* str, BasicType type) : _tt(tt_symbolic), _bt(type) {
 156       _value.j = (intptr_t)str;
 157     }
 158 
 159     TokenType token_type()  const { return _tt; }
 160     BasicType basic_type()  const { return _bt; }
 161     bool      has_index()   const { return _tt == tt_parameter || _tt == tt_temporary; }
 162     int       index()       const { assert(has_index(), "must have index");; return _value.i; }
 163     Handle    object()      const { assert(_bt == T_OBJECT, "wrong accessor"); assert(_tt == tt_constant, "value type"); return _handle; }
 164     const char* str()       const { assert(_tt == tt_symbolic, "string type"); return (const char*)(intptr_t)_value.j; }
 165 
 166     jint      get_jint()    const { assert(_bt == T_INT || is_subword_type(_bt), "wrong accessor"); assert(_tt == tt_constant, "value types"); return _value.i; }
 167     jlong     get_jlong()   const { assert(_bt == T_LONG, "wrong accessor");   assert(_tt == tt_constant, "value types"); return _value.j; }
 168     jfloat    get_jfloat()  const { assert(_bt == T_FLOAT, "wrong accessor");  assert(_tt == tt_constant, "value types"); return _value.f; }
 169     jdouble   get_jdouble() const { assert(_bt == T_DOUBLE, "wrong accessor"); assert(_tt == tt_constant, "value types"); return _value.d; }
 170   };
 171 
 172 private:
 173   MethodHandleChain _chain;
 174   bool              _for_invokedynamic;
 175   int               _local_index;
 176 
 177   // This array is kept in an unusual order, indexed by low-level "slot number".
 178   // TOS is always _outgoing.at(0), so simple pushes and pops shift the whole _outgoing array.
 179   // If there is a receiver in the current argument list, it is at _outgoing.at(_outgoing.length()-1).
 180   // If a value at _outgoing.at(n) is T_LONG or T_DOUBLE, the value at _outgoing.at(n+1) is T_VOID.
 181   GrowableArray<ArgToken>  _outgoing;       // current outgoing parameter slots
 182   int                      _outgoing_argc;  // # non-empty outgoing slots
 183 
 184   // Replace a value of type old_type at slot (and maybe slot+1) with the new value.
 185   // If old_type != T_VOID, remove the old argument at that point.
 186   // If new_type != T_VOID, insert the new argument at that point.
 187   // Insert or delete a second empty slot as needed.
 188   void change_argument(BasicType old_type, int slot, const ArgToken& new_arg);
 189   void change_argument(BasicType old_type, int slot, BasicType type, const ArgToken& new_arg) {
 190     assert(type == new_arg.basic_type(), "must agree");
 191     change_argument(old_type, slot, new_arg);
 192   }
 193 
 194   // Raw retype conversions for OP_RAW_RETYPE.
 195   void retype_raw_conversion(BasicType src, BasicType dst, bool for_return, int slot, TRAPS);
 196   void retype_raw_argument_type(BasicType src, BasicType dst, int slot, TRAPS) { retype_raw_conversion(src, dst, false, slot, CHECK); }
 197   void retype_raw_return_type(  BasicType src, BasicType dst,           TRAPS) { retype_raw_conversion(src, dst, true,  -1,   CHECK); }
 198 
 199   BasicType arg_type(int slot) {
 200     return _outgoing.at(slot).basic_type();
 201   }
 202   bool has_argument(int slot) {
 203     return arg_type(slot) < T_VOID;
 204   }
 205 
 206 #ifdef ASSERT
 207   int argument_count_slow();
 208 #endif
 209 
 210   // Return a bytecode for converting src to dest, if one exists.
 211   Bytecodes::Code conversion_code(BasicType src, BasicType dest);
 212 
 213   void walk_incoming_state(TRAPS);
 214 
 215   void verify_args_and_signature(TRAPS) NOT_DEBUG_RETURN;
 216 
 217 public:
 218   MethodHandleWalker(Handle root, bool for_invokedynamic, TRAPS)
 219     : _chain(root, THREAD),
 220       _for_invokedynamic(for_invokedynamic),
 221       _outgoing(THREAD, 10),
 222       _outgoing_argc(0)
 223   {
 224     _local_index = for_invokedynamic ? 0 : 1;
 225   }
 226 
 227   MethodHandleChain& chain() { return _chain; }
 228 
 229   bool for_invokedynamic() const { return _for_invokedynamic; }
 230 
 231   int new_local_index(BasicType bt) {
 232     //int index = _for_invokedynamic ? _local_index : _local_index - 1;
 233     int index = _local_index;
 234     _local_index += type2size[bt];
 235     return index;
 236   }
 237 
 238   int max_locals() const { return _local_index; }
 239 
 240   // plug-in abstract interpretation steps:
 241   virtual ArgToken make_parameter(BasicType type, klassOop tk, int argnum, TRAPS) = 0;
 242   virtual ArgToken make_prim_constant(BasicType type, jvalue* con, TRAPS) = 0;
 243   virtual ArgToken make_oop_constant(oop con, TRAPS) = 0;
 244   virtual ArgToken make_conversion(BasicType type, klassOop tk, Bytecodes::Code op, const ArgToken& src, TRAPS) = 0;
 245   virtual ArgToken make_fetch(BasicType type, klassOop tk, Bytecodes::Code op, const ArgToken& base, const ArgToken& offset, TRAPS) = 0;
 246   virtual ArgToken make_invoke(methodOop m, vmIntrinsics::ID iid, Bytecodes::Code op, bool tailcall, int argc, ArgToken* argv, TRAPS) = 0;
 247 
 248   // For make_invoke, the methodOop can be NULL if the intrinsic ID
 249   // is something other than vmIntrinsics::_none.
 250 
 251   // and in case anyone cares to related the previous actions to the chain:
 252   virtual void set_method_handle(oop mh) { }
 253 
 254   void lose(const char* msg, TRAPS) { chain().lose(msg, THREAD); }
 255   const char* lose_message()        { return chain().lose_message(); }
 256 
 257   ArgToken walk(TRAPS);
 258 };
 259 
 260 
 261 // An abstract interpreter for method handle chains.
 262 // Produces an account of the semantics of a chain, in terms of a static IR.
 263 // The IR happens to be JVM bytecodes.
 264 class MethodHandleCompiler : public MethodHandleWalker {
 265 private:
 266   int          _invoke_count;  // count the original call site has been executed
 267   KlassHandle  _rklass;        // Return type for casting.
 268   BasicType    _rtype;
 269   KlassHandle  _target_klass;
 270   Thread*      _thread;
 271 
 272   // Values used by the compiler.
 273   static jvalue zero_jvalue;
 274   static jvalue one_jvalue;
 275 
 276   // Fake constant pool entry.
 277   class ConstantValue {
 278   private:
 279     int       _tag;   // Constant pool tag type.
 280     JavaValue _value;
 281     Handle    _handle;
 282     Symbol*   _sym;
 283 
 284   public:
 285     // Constructor for oop types.
 286     ConstantValue(int tag, Handle con) : _tag(tag), _handle(con) {
 287       assert(tag == JVM_CONSTANT_Class  ||
 288              tag == JVM_CONSTANT_String ||
 289              tag == JVM_CONSTANT_Object, "must be oop type");
 290     }
 291 
 292     ConstantValue(int tag, Symbol* con) : _tag(tag), _sym(con) {
 293       assert(tag == JVM_CONSTANT_Utf8, "must be symbol type");
 294     }
 295 
 296     // Constructor for oop reference types.
 297     ConstantValue(int tag, int index) : _tag(tag) {
 298       assert(JVM_CONSTANT_Fieldref <= tag && tag <= JVM_CONSTANT_NameAndType, "must be ref type");
 299       _value.set_jint(index);
 300     }
 301     ConstantValue(int tag, int first_index, int second_index) : _tag(tag) {
 302       assert(JVM_CONSTANT_Fieldref <= tag && tag <= JVM_CONSTANT_NameAndType, "must be ref type");
 303       _value.set_jint(first_index << 16 | second_index);
 304     }
 305 
 306     // Constructor for primitive types.
 307     ConstantValue(BasicType bt, jvalue con) {
 308       _value.set_type(bt);
 309       switch (bt) {
 310       case T_INT:    _tag = JVM_CONSTANT_Integer; _value.set_jint(   con.i); break;
 311       case T_LONG:   _tag = JVM_CONSTANT_Long;    _value.set_jlong(  con.j); break;
 312       case T_FLOAT:  _tag = JVM_CONSTANT_Float;   _value.set_jfloat( con.f); break;
 313       case T_DOUBLE: _tag = JVM_CONSTANT_Double;  _value.set_jdouble(con.d); break;
 314       default: ShouldNotReachHere();
 315       }
 316     }
 317 
 318     int       tag()          const { return _tag; }
 319     Symbol*   symbol()       const { return _sym; }
 320     klassOop  klass_oop()    const { return (klassOop)  _handle(); }
 321     oop       object_oop()   const { return _handle(); }
 322     int       index()        const { return _value.get_jint(); }
 323     int       first_index()  const { return _value.get_jint() >> 16; }
 324     int       second_index() const { return _value.get_jint() & 0x0000FFFF; }
 325 
 326     bool      is_primitive() const { return is_java_primitive(_value.get_type()); }
 327     jint      get_jint()     const { return _value.get_jint();    }
 328     jlong     get_jlong()    const { return _value.get_jlong();   }
 329     jfloat    get_jfloat()   const { return _value.get_jfloat();  }
 330     jdouble   get_jdouble()  const { return _value.get_jdouble(); }
 331   };
 332 
 333   // Fake constant pool.
 334   GrowableArray<ConstantValue*> _constants;
 335 
 336   // Accumulated compiler state:
 337   GrowableArray<unsigned char> _bytecode;
 338 
 339   int _cur_stack;
 340   int _max_stack;
 341   int _num_params;
 342   int _name_index;
 343   int _signature_index;
 344 
 345   void stack_push(BasicType bt) {
 346     _cur_stack += type2size[bt];
 347     if (_cur_stack > _max_stack) _max_stack = _cur_stack;
 348   }
 349   void stack_pop(BasicType bt) {
 350     _cur_stack -= type2size[bt];
 351     assert(_cur_stack >= 0, "sanity");
 352   }
 353 
 354   unsigned char* bytecode()        const { return _bytecode.adr_at(0); }
 355   int            bytecode_length() const { return _bytecode.length(); }
 356 
 357   // Fake constant pool.
 358   int cpool_oop_put(int tag, Handle con) {
 359     if (con.is_null())  return 0;
 360     ConstantValue* cv = new ConstantValue(tag, con);
 361     return _constants.append(cv);
 362   }
 363 
 364   int cpool_symbol_put(int tag, Symbol* con) {
 365     if (con == NULL)  return 0;
 366     ConstantValue* cv = new ConstantValue(tag, con);
 367     con->increment_refcount();
 368     return _constants.append(cv);
 369   }
 370 
 371   int cpool_oop_reference_put(int tag, int first_index, int second_index) {
 372     if (first_index == 0 && second_index == 0)  return 0;
 373     assert(first_index != 0 && second_index != 0, "no zero indexes");
 374     ConstantValue* cv = new ConstantValue(tag, first_index, second_index);
 375     return _constants.append(cv);
 376   }
 377 
 378   int cpool_primitive_put(BasicType type, jvalue* con);
 379 
 380   int cpool_int_put(jint value) {
 381     jvalue con; con.i = value;
 382     return cpool_primitive_put(T_INT, &con);
 383   }
 384   int cpool_long_put(jlong value) {
 385     jvalue con; con.j = value;
 386     return cpool_primitive_put(T_LONG, &con);
 387   }
 388   int cpool_float_put(jfloat value) {
 389     jvalue con; con.f = value;
 390     return cpool_primitive_put(T_FLOAT, &con);
 391   }
 392   int cpool_double_put(jdouble value) {
 393     jvalue con; con.d = value;
 394     return cpool_primitive_put(T_DOUBLE, &con);
 395   }
 396 
 397   int cpool_object_put(Handle obj) {
 398     return cpool_oop_put(JVM_CONSTANT_Object, obj);
 399   }
 400   int cpool_symbol_put(Symbol* sym) {
 401     return cpool_symbol_put(JVM_CONSTANT_Utf8, sym);
 402   }
 403   int cpool_klass_put(klassOop klass) {
 404     return cpool_oop_put(JVM_CONSTANT_Class, klass);
 405   }
 406   int cpool_methodref_put(int class_index, int name_and_type_index) {
 407     return cpool_oop_reference_put(JVM_CONSTANT_Methodref, class_index, name_and_type_index);
 408   }
 409   int cpool_name_and_type_put(int name_index, int signature_index) {
 410     return cpool_oop_reference_put(JVM_CONSTANT_NameAndType, name_index, signature_index);
 411   }
 412 
 413   void emit_bc(Bytecodes::Code op, int index = 0, int args_size = -1);
 414   void emit_load(BasicType bt, int index);
 415   void emit_store(BasicType bt, int index);
 416   void emit_load_constant(ArgToken arg);
 417 
 418   virtual ArgToken make_parameter(BasicType type, klassOop tk, int argnum, TRAPS) {
 419     return ArgToken(tt_parameter, type, argnum);
 420   }
 421   virtual ArgToken make_oop_constant(oop con, TRAPS) {
 422     Handle h(THREAD, con);
 423     return ArgToken(h);
 424   }
 425   virtual ArgToken make_prim_constant(BasicType type, jvalue* con, TRAPS) {
 426     return ArgToken(type, *con);
 427   }
 428 
 429   virtual ArgToken make_conversion(BasicType type, klassOop tk, Bytecodes::Code op, const ArgToken& src, TRAPS);
 430   virtual ArgToken make_fetch(BasicType type, klassOop tk, Bytecodes::Code op, const ArgToken& base, const ArgToken& offset, TRAPS);
 431   virtual ArgToken make_invoke(methodOop m, vmIntrinsics::ID iid, Bytecodes::Code op, bool tailcall, int argc, ArgToken* argv, TRAPS);
 432 
 433   // Get a real constant pool.
 434   constantPoolHandle get_constant_pool(TRAPS) const;
 435 
 436   // Get a real methodOop.
 437   methodHandle get_method_oop(TRAPS) const;
 438 
 439 public:
 440   MethodHandleCompiler(Handle root, Symbol* name, Symbol* signature, int invoke_count, bool for_invokedynamic, TRAPS);
 441 
 442   // Compile the given MH chain into bytecode.
 443   methodHandle compile(TRAPS);
 444 
 445   // Tests if the given class is a MH adapter holder.
 446   static bool klass_is_method_handle_adapter_holder(klassOop klass) {
 447     return (klass == SystemDictionary::MethodHandle_klass());
 448   }
 449 };
 450 
 451 #endif // SHARE_VM_PRIMS_METHODHANDLEWALK_HPP