1 /*

     2  * Copyright 2008-2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    20  * CA 95054 USA or visit www.sun.com if you need additional information or

    21  * have any questions.

    22  *

    23  */

    24 

    25 class MacroAssembler;

    26 class Label;

    27 class MethodHandleEntry;

    28 

    29 class MethodHandles: AllStatic {

    30   // JVM support for MethodHandle, MethodType, and related types

    31   // in java.dyn and java.dyn.hotspot.

    32   // See also  javaClasses for layouts java_dyn_Method{Handle,Type,Type::Form}.

    33  public:

    34   enum EntryKind {

    35     _check_mtype,               // how a caller calls a MH

    36     _wrong_method_type,         // what happens when there is a type mismatch

    37     _invokestatic_mh,           // how a MH emulates invokestatic

    38     _invokespecial_mh,          // ditto for the other invokes...

    39     _invokevirtual_mh,

    40     _invokeinterface_mh,

    41     _bound_ref_mh,              // reference argument is bound

    42     _bound_int_mh,              // int argument is bound (via an Integer or Float)

    43     _bound_long_mh,             // long argument is bound (via a Long or Double)

    44     _bound_ref_direct_mh,       // same as above, with direct linkage to methodOop

    45     _bound_int_direct_mh,

    46     _bound_long_direct_mh,

    47 

    48     _adapter_mh_first,     // adapter sequence goes here...

    49     _adapter_retype_only   = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_RETYPE_ONLY,

    50     _adapter_check_cast    = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_CHECK_CAST,

    51     _adapter_prim_to_prim  = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_PRIM_TO_PRIM,

    52     _adapter_ref_to_prim   = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_REF_TO_PRIM,

    53     _adapter_prim_to_ref   = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_PRIM_TO_REF,

    54     _adapter_swap_args     = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_SWAP_ARGS,

    55     _adapter_rot_args      = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_ROT_ARGS,

    56     _adapter_dup_args      = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_DUP_ARGS,

    57     _adapter_drop_args     = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_DROP_ARGS,

    58     _adapter_collect_args  = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_COLLECT_ARGS,

    59     _adapter_spread_args   = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_SPREAD_ARGS,

    60     _adapter_flyby         = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_FLYBY,

    61     _adapter_ricochet      = _adapter_mh_first + sun_dyn_AdapterMethodHandle::OP_RICOCHET,

    62     _adapter_mh_last       = _adapter_mh_first + sun_dyn_AdapterMethodHandle::CONV_OP_LIMIT - 1,

    63 

    64     // Optimized adapter types

    65 

    66     // argument list reordering

    67     _adapter_opt_swap_1,

    68     _adapter_opt_swap_2,

    69     _adapter_opt_rot_1_up,

    70     _adapter_opt_rot_1_down,

    71     _adapter_opt_rot_2_up,

    72     _adapter_opt_rot_2_down,

    73     // primitive single to single:

    74     _adapter_opt_i2i,           // i2c, i2z, i2b, i2s

    75     // primitive double to single:

    76     _adapter_opt_l2i,

    77     _adapter_opt_d2f,

    78     // primitive single to double:

    79     _adapter_opt_i2l,

    80     _adapter_opt_f2d,

    81     // conversion between floating point and integer type is handled by Java

    82 

    83     // reference to primitive:

    84     _adapter_opt_unboxi,

    85     _adapter_opt_unboxl,

    86 

    87     // spreading (array length cases 0, 1, >=2)

    88     _adapter_opt_spread_0,

    89     _adapter_opt_spread_1,

    90     _adapter_opt_spread_more,

    91 

    92     _EK_LIMIT,

    93     _EK_FIRST = 0

    94   };

    95 

    96  public:

    97   static bool enabled()                         { return _enabled; }

    98   static void set_enabled(bool z);

    99 

   100  private:

   101   enum {  // import sun_dyn_AdapterMethodHandle::CONV_OP_*

   102     CONV_OP_LIMIT         = sun_dyn_AdapterMethodHandle::CONV_OP_LIMIT,

   103     CONV_OP_MASK          = sun_dyn_AdapterMethodHandle::CONV_OP_MASK,

   104     CONV_VMINFO_MASK      = sun_dyn_AdapterMethodHandle::CONV_VMINFO_MASK,

   105     CONV_VMINFO_SHIFT     = sun_dyn_AdapterMethodHandle::CONV_VMINFO_SHIFT,

   106     CONV_OP_SHIFT         = sun_dyn_AdapterMethodHandle::CONV_OP_SHIFT,

   107     CONV_DEST_TYPE_SHIFT  = sun_dyn_AdapterMethodHandle::CONV_DEST_TYPE_SHIFT,

   108     CONV_SRC_TYPE_SHIFT   = sun_dyn_AdapterMethodHandle::CONV_SRC_TYPE_SHIFT,

   109     CONV_STACK_MOVE_SHIFT = sun_dyn_AdapterMethodHandle::CONV_STACK_MOVE_SHIFT,

   110     CONV_STACK_MOVE_MASK  = sun_dyn_AdapterMethodHandle::CONV_STACK_MOVE_MASK

   111   };

   112 

   113   static bool _enabled;

   114   static MethodHandleEntry* _entries[_EK_LIMIT];

   115   static const char*        _entry_names[_EK_LIMIT+1];

   116   static bool ek_valid(EntryKind ek)            { return (uint)ek < (uint)_EK_LIMIT; }

   117   static bool conv_op_valid(int op)             { return (uint)op < (uint)CONV_OP_LIMIT; }

   118 

   119  public:

   120   static bool    have_entry(EntryKind ek)       { return ek_valid(ek) && _entries[ek] != NULL; }

   121   static MethodHandleEntry* entry(EntryKind ek) { assert(ek_valid(ek), "initialized");

   122                                                   return _entries[ek]; }

   123   static const char* entry_name(EntryKind ek)   { assert(ek_valid(ek), "oob");

   124                                                   return _entry_names[ek]; }

   125   static EntryKind adapter_entry_kind(int op)   { assert(conv_op_valid(op), "oob");

   126                                                   return EntryKind(_adapter_mh_first + op); }

   127 

   128   static void init_entry(EntryKind ek, MethodHandleEntry* me) {

   129     assert(ek_valid(ek), "oob");

   130     assert(_entries[ek] == NULL, "no double initialization");

   131     _entries[ek] = me;

   132   }

   133 

   134   static jint adapter_conversion(int conv_op, BasicType src, BasicType dest,

   135                                  int stack_move = 0, int vminfo = 0) {

   136     assert(conv_op_valid(conv_op), "oob");

   137     jint conv = ((conv_op      << CONV_OP_SHIFT)

   138                  | (src        << CONV_SRC_TYPE_SHIFT)

   139                  | (dest       << CONV_DEST_TYPE_SHIFT)

   140                  | (stack_move << CONV_STACK_MOVE_SHIFT)

   141                  | (vminfo     << CONV_VMINFO_SHIFT)

   142                  );

   143     assert(adapter_conversion_op(conv) == conv_op, "decode conv_op");

   144     assert(adapter_conversion_src_type(conv) == src, "decode src");

   145     assert(adapter_conversion_dest_type(conv) == dest, "decode dest");

   146     assert(adapter_conversion_stack_move(conv) == stack_move, "decode stack_move");

   147     assert(adapter_conversion_vminfo(conv) == vminfo, "decode vminfo");

   148     return conv;

   149   }

   150   static int adapter_conversion_op(jint conv) {

   151     return ((conv >> CONV_OP_SHIFT) & 0xF);

   152   }

   153   static BasicType adapter_conversion_src_type(jint conv) {

   154     return (BasicType)((conv >> CONV_SRC_TYPE_SHIFT) & 0xF);

   155   }

   156   static BasicType adapter_conversion_dest_type(jint conv) {

   157     return (BasicType)((conv >> CONV_DEST_TYPE_SHIFT) & 0xF);

   158   }

   159   static int adapter_conversion_stack_move(jint conv) {

   160     return (conv >> CONV_STACK_MOVE_SHIFT);

   161   }

   162   static int adapter_conversion_vminfo(jint conv) {

   163     return (conv >> CONV_VMINFO_SHIFT) & CONV_VMINFO_MASK;

   164   }

   165 

   166   // Offset in words that the interpreter stack pointer moves when an argument is pushed.

   167   // The stack_move value must always be a multiple of this.

   168   static int stack_move_unit() {

   169     return frame::interpreter_frame_expression_stack_direction() * Interpreter::stackElementWords();

   170   }

   171 

   172   enum { CONV_VMINFO_SIGN_FLAG = 0x80 };

   173   static int adapter_subword_vminfo(BasicType dest) {

   174     if (dest == T_BOOLEAN) return (BitsPerInt -  1);

   175     if (dest == T_CHAR)    return (BitsPerInt - 16);

   176     if (dest == T_BYTE)    return (BitsPerInt -  8) | CONV_VMINFO_SIGN_FLAG;

   177     if (dest == T_SHORT)   return (BitsPerInt - 16) | CONV_VMINFO_SIGN_FLAG;

   178     return 0;                   // case T_INT

   179   }

   180   // Here is the transformation the i2i adapter must perform:

   181   static int truncate_subword_from_vminfo(jint value, int vminfo) {

   182     jint tem = value << vminfo;

   183     if ((vminfo & CONV_VMINFO_SIGN_FLAG) != 0) {

   184       return (jint)tem >> vminfo;

   185     } else {

   186       return (juint)tem >> vminfo;

   187     }

   188   }

   189 

   190   static inline address from_compiled_entry(EntryKind ek);

   191   static inline address from_interpreted_entry(EntryKind ek);

   192 

   193   // helpers for decode_method.

   194   static methodOop decode_methodOop(methodOop m, int& decode_flags_result);

   195   static methodOop decode_vmtarget(oop vmtarget, int vmindex, oop mtype, klassOop& receiver_limit_result, int& decode_flags_result);

   196   static methodOop decode_MemberName(oop mname, klassOop& receiver_limit_result, int& decode_flags_result);

   197   static methodOop decode_MethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result);

   198   static methodOop decode_DirectMethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result);

   199   static methodOop decode_BoundMethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result);

   200   static methodOop decode_AdapterMethodHandle(oop mh, klassOop& receiver_limit_result, int& decode_flags_result);

   201 

   202   // Find out how many stack slots an mh pushes or pops.

   203   // The result is *not* reported as a multiple of stack_move_unit();

   204   // It is a signed net number of pushes (a difference in vmslots).

   205   // To compare with a stack_move value, first multiply by stack_move_unit().

   206   static int decode_MethodHandle_stack_pushes(oop mh);

   207 

   208  public:

   209   // working with member names

   210   static void resolve_MemberName(Handle mname, TRAPS); // compute vmtarget/vmindex from name/type

   211   static void expand_MemberName(Handle mname, int suppress, TRAPS);  // expand defc/name/type if missing

   212   static void init_MemberName(oop mname_oop, oop target); // compute vmtarget/vmindex from target

   213   static void init_MemberName(oop mname_oop, methodOop m, bool do_dispatch);

   214   static void init_MemberName(oop mname_oop, klassOop field_holder, AccessFlags mods, int offset);

   215   static int find_MemberNames(klassOop k, symbolOop name, symbolOop sig,

   216                               int mflags, klassOop caller,

   217                               int skip, objArrayOop results);

   218   // bit values for suppress argument to expand_MemberName:

   219   enum { _suppress_defc = 1, _suppress_name = 2, _suppress_type = 4 };

   220 

   221   // called from InterpreterGenerator and StubGenerator

   222   static address generate_method_handle_interpreter_entry(MacroAssembler* _masm);

   223   static void generate_method_handle_stub(MacroAssembler* _masm, EntryKind ek);

   224 

   225   // argument list parsing

   226   static int argument_slot(oop method_type, int arg);

   227   static int argument_slot_count(oop method_type) { return argument_slot(method_type, -1); }

   228   static int argument_slot_to_argnum(oop method_type, int argslot);

   229 

   230   // Runtime support

   231   enum {                        // bit-encoded flags from decode_method or decode_vmref

   232     _dmf_has_receiver   = 0x01, // target method has leading reference argument

   233     _dmf_does_dispatch  = 0x02, // method handle performs virtual or interface dispatch

   234     _dmf_from_interface = 0x04, // peforms interface dispatch

   235     _DMF_DIRECT_MASK    = (_dmf_from_interface*2 - _dmf_has_receiver),

   236     _dmf_binds_method   = 0x08,

   237     _dmf_binds_argument = 0x10,

   238     _DMF_BOUND_MASK     = (_dmf_binds_argument*2 - _dmf_binds_method),

   239     _dmf_adapter_lsb    = 0x20,

   240     _DMF_ADAPTER_MASK   = (_dmf_adapter_lsb << CONV_OP_LIMIT) - _dmf_adapter_lsb

   241   };

   242   static methodOop decode_method(oop x, klassOop& receiver_limit_result, int& decode_flags_result);

   243   enum {

   244     // format of query to getConstant:

   245     GC_JVM_PUSH_LIMIT = 0,

   246     GC_JVM_STACK_MOVE_LIMIT = 1,

   247 

   248     // format of result from getTarget / encode_target:

   249     ETF_HANDLE_OR_METHOD_NAME = 0, // all available data (immediate MH or method)

   250     ETF_DIRECT_HANDLE         = 1, // ultimate method handle (will be a DMH, may be self)

   251     ETF_METHOD_NAME           = 2, // ultimate method as MemberName

   252     ETF_REFLECT_METHOD        = 3  // ultimate method as java.lang.reflect object (sans refClass)

   253   };

   254   static int get_named_constant(int which, Handle name_box, TRAPS);

   255   static oop encode_target(Handle mh, int format, TRAPS); // report vmtarget (to Java code)

   256   static bool class_cast_needed(klassOop src, klassOop dst);

   257 

   258  private:

   259   // These checkers operate on a pair of whole MethodTypes:

   260   static const char* check_method_type_change(oop src_mtype, int src_beg, int src_end,

   261                                               int insert_argnum, oop insert_type,

   262                                               int change_argnum, oop change_type,

   263                                               int delete_argnum,

   264                                               oop dst_mtype, int dst_beg, int dst_end);

   265   static const char* check_method_type_insertion(oop src_mtype,

   266                                                  int insert_argnum, oop insert_type,

   267                                                  oop dst_mtype) {

   268     oop no_ref = NULL;

   269     return check_method_type_change(src_mtype, 0, -1,

   270                                     insert_argnum, insert_type,

   271                                     -1, no_ref, -1, dst_mtype, 0, -1);

   272   }

   273   static const char* check_method_type_conversion(oop src_mtype,

   274                                                   int change_argnum, oop change_type,

   275                                                   oop dst_mtype) {

   276     oop no_ref = NULL;

   277     return check_method_type_change(src_mtype, 0, -1, -1, no_ref,

   278                                     change_argnum, change_type,

   279                                     -1, dst_mtype, 0, -1);

   280   }

   281   static const char* check_method_type_passthrough(oop src_mtype, oop dst_mtype) {

   282     oop no_ref = NULL;

   283     return check_method_type_change(src_mtype, 0, -1,

   284                                     -1, no_ref, -1, no_ref, -1,

   285                                     dst_mtype, 0, -1);

   286   }

   287 

   288   // These checkers operate on pairs of argument or return types:

   289   static const char* check_argument_type_change(BasicType src_type, klassOop src_klass,

   290                                                 BasicType dst_type, klassOop dst_klass,

   291                                                 int argnum);

   292 

   293   static const char* check_argument_type_change(oop src_type, oop dst_type,

   294                                                 int argnum) {

   295     klassOop src_klass = NULL, dst_klass = NULL;

   296     BasicType src_bt = java_lang_Class::as_BasicType(src_type, &src_klass);

   297     BasicType dst_bt = java_lang_Class::as_BasicType(dst_type, &dst_klass);

   298     return check_argument_type_change(src_bt, src_klass,

   299                                       dst_bt, dst_klass, argnum);

   300   }

   301 

   302   static const char* check_return_type_change(oop src_type, oop dst_type) {

   303     return check_argument_type_change(src_type, dst_type, -1);

   304   }

   305 

   306   static const char* check_return_type_change(BasicType src_type, klassOop src_klass,

   307                                               BasicType dst_type, klassOop dst_klass) {

   308     return check_argument_type_change(src_type, src_klass, dst_type, dst_klass, -1);

   309   }

   310 

   311   static const char* check_method_receiver(methodOop m, klassOop passed_recv_type);

   312 

   313   // These verifiers can block, and will throw an error if the checking fails:

   314   static void verify_vmslots(Handle mh, TRAPS);

   315   static void verify_vmargslot(Handle mh, int argnum, int argslot, TRAPS);

   316 

   317   static void verify_method_type(methodHandle m, Handle mtype,

   318                                  bool has_bound_oop,

   319                                  KlassHandle bound_oop_type,

   320                                  TRAPS);

   321 

   322   static void verify_method_signature(methodHandle m, Handle mtype,

   323                                       int first_ptype_pos,

   324                                       KlassHandle insert_ptype, TRAPS);

   325 

   326   static void verify_DirectMethodHandle(Handle mh, methodHandle m, TRAPS);

   327   static void verify_BoundMethodHandle(Handle mh, Handle target, int argnum,

   328                                        bool direct_to_method, TRAPS);

   329   static void verify_BoundMethodHandle_with_receiver(Handle mh, methodHandle m, TRAPS);

   330   static void verify_AdapterMethodHandle(Handle mh, int argnum, TRAPS);

   331 

   332  public:

   333 

   334   // Fill in the fields of a DirectMethodHandle mh.  (MH.type must be pre-filled.)

   335   static void init_DirectMethodHandle(Handle mh, methodHandle method, bool do_dispatch, TRAPS);

   336 

   337   // Fill in the fields of a BoundMethodHandle mh.  (MH.type, BMH.argument must be pre-filled.)

   338   static void init_BoundMethodHandle(Handle mh, Handle target, int argnum, TRAPS);

   339   static void init_BoundMethodHandle_with_receiver(Handle mh,

   340                                                    methodHandle original_m,

   341                                                    KlassHandle receiver_limit,

   342                                                    int decode_flags,

   343                                                    TRAPS);

   344 

   345   // Fill in the fields of an AdapterMethodHandle mh.  (MH.type must be pre-filled.)

   346   static void init_AdapterMethodHandle(Handle mh, Handle target, int argnum, TRAPS);

   347 

   348 #ifdef ASSERT

   349   static bool spot_check_entry_names();

   350 #endif

   351 

   352  private:

   353   static methodHandle dispatch_decoded_method(methodHandle m,

   354                                               KlassHandle receiver_limit,

   355                                               int decode_flags,

   356                                               KlassHandle receiver_klass,

   357                                               TRAPS);

   358 

   359   static bool same_basic_type_for_arguments(BasicType src, BasicType dst,

   360                                             bool for_return = false);

   361   static bool same_basic_type_for_returns(BasicType src, BasicType dst) {

   362     return same_basic_type_for_arguments(src, dst, true);

   363   }

   364 

   365   enum {                        // arg_mask values

   366     _INSERT_NO_MASK   = -1,

   367     _INSERT_REF_MASK  = 0,

   368     _INSERT_INT_MASK  = 1,

   369     _INSERT_LONG_MASK = 3

   370   };

   371   static void insert_arg_slots(MacroAssembler* _masm,

   372                                RegisterOrConstant arg_slots,

   373                                int arg_mask,

   374                                Register rax_argslot,

   375                                Register rbx_temp, Register rdx_temp);

   376 

   377   static void remove_arg_slots(MacroAssembler* _masm,

   378                                RegisterOrConstant arg_slots,

   379                                Register rax_argslot,

   380                                Register rbx_temp, Register rdx_temp);

   381 };

   382 

   383 

   384 // Access methods for the "entry" field of a java.dyn.MethodHandle.

   385 // The field is primarily a jump target for compiled calls.

   386 // However, we squirrel away some nice pointers for other uses,

   387 // just before the jump target.

   388 // Aspects of a method handle entry:

   389 //  - from_compiled_entry - stub used when compiled code calls the MH

   390 //  - from_interpreted_entry - stub used when the interpreter calls the MH

   391 //  - type_checking_entry - stub for runtime casting between MHForm siblings (NYI)

   392 class MethodHandleEntry {

   393  public:

   394   class Data {

   395     friend class MethodHandleEntry;

   396     size_t              _total_size; // size including Data and code stub

   397     MethodHandleEntry*  _type_checking_entry;

   398     address             _from_interpreted_entry;

   399     MethodHandleEntry* method_entry() { return (MethodHandleEntry*)(this + 1); }

   400   };

   401 

   402   Data*     data()                              { return (Data*)this - 1; }

   403 

   404   address   start_address()                     { return (address) data(); }

   405   address   end_address()                       { return start_address() + data()->_total_size; }

   406 

   407   address   from_compiled_entry()               { return (address) this; }

   408 

   409   address   from_interpreted_entry()            { return data()->_from_interpreted_entry; }

   410   void  set_from_interpreted_entry(address e)   { data()->_from_interpreted_entry = e; }

   411 

   412   MethodHandleEntry* type_checking_entry()           { return data()->_type_checking_entry; }

   413   void set_type_checking_entry(MethodHandleEntry* e) { data()->_type_checking_entry = e; }

   414 

   415   void set_end_address(address end_addr) {

   416     size_t total_size = end_addr - start_address();

   417     assert(total_size > 0 && total_size < 0x1000, "reasonable end address");

   418     data()->_total_size = total_size;

   419   }

   420 

   421   // Compiler support:

   422   static int from_interpreted_entry_offset_in_bytes() {

   423     return (int)( offset_of(Data, _from_interpreted_entry) - sizeof(Data) );

   424   }

   425   static int type_checking_entry_offset_in_bytes() {

   426     return (int)( offset_of(Data, _from_interpreted_entry) - sizeof(Data) );

   427   }

   428 

   429   static address            start_compiled_entry(MacroAssembler* _masm,

   430                                                  address interpreted_entry = NULL);

   431   static MethodHandleEntry* finish_compiled_entry(MacroAssembler* masm, address start_addr);

   432 };

   433 

   434 address MethodHandles::from_compiled_entry(EntryKind ek) { return entry(ek)->from_compiled_entry(); }

   435 address MethodHandles::from_interpreted_entry(EntryKind ek) { return entry(ek)->from_interpreted_entry(); }