1 /*

     2  * Copyright (c) 1999, 2016, 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 "ci/ciCallSite.hpp"

    27 #include "ci/ciConstant.hpp"

    28 #include "ci/ciField.hpp"

    29 #include "ci/ciStreams.hpp"

    30 #include "ci/ciUtilities.hpp"

    31 

    32 // ciExceptionHandlerStream

    33 //

    34 // Walk over some selected set of a methods exception handlers.

    35 

    36 // ------------------------------------------------------------------

    37 // ciExceptionHandlerStream::count

    38 //

    39 // How many exception handlers are there in this stream?

    40 //

    41 // Implementation note: Compiler2 needs this functionality, so I had

    42 int ciExceptionHandlerStream::count() {

    43   int save_pos = _pos;

    44   int save_end = _end;

    45 

    46   int count = 0;

    47 

    48   _pos = -1;

    49   _end = _method->_handler_count;

    50 

    51 

    52   next();

    53   while (!is_done()) {

    54     count++;

    55     next();

    56   }

    57 

    58   _pos = save_pos;

    59   _end = save_end;

    60 

    61   return count;

    62 }

    63 

    64 int ciExceptionHandlerStream::count_remaining() {

    65   int save_pos = _pos;

    66   int save_end = _end;

    67 

    68   int count = 0;

    69 

    70   while (!is_done()) {

    71     count++;

    72     next();

    73   }

    74 

    75   _pos = save_pos;

    76   _end = save_end;

    77 

    78   return count;

    79 }

    80 

    81 // ciBytecodeStream

    82 //

    83 // The class is used to iterate over the bytecodes of a method.

    84 // It hides the details of constant pool structure/access by

    85 // providing accessors for constant pool items.

    86 

    87 // ------------------------------------------------------------------

    88 // ciBytecodeStream::next_wide_or_table

    89 //

    90 // Special handling for switch ops

    91 Bytecodes::Code ciBytecodeStream::next_wide_or_table(Bytecodes::Code bc) {

    92   switch (bc) {                // Check for special bytecode handling

    93   case Bytecodes::_wide:

    94     // Special handling for the wide bytcode

    95     // Get following bytecode; do not return wide

    96     assert(Bytecodes::Code(_pc[0]) == Bytecodes::_wide, "");

    97     bc = Bytecodes::java_code(_raw_bc = (Bytecodes::Code)_pc[1]);

    98     assert(Bytecodes::wide_length_for(bc) > 2, "must make progress");

    99     _pc += Bytecodes::wide_length_for(bc);

   100     _was_wide = _pc;              // Flag last wide bytecode found

   101     assert(is_wide(), "accessor works right");

   102     break;

   103 

   104   case Bytecodes::_lookupswitch:

   105     _pc++;                      // Skip wide bytecode

   106     _pc += (_start-_pc)&3;      // Word align

   107     _table_base = (jint*)_pc;   // Capture for later usage

   108                                 // table_base[0] is default far_dest

   109     // Table has 2 lead elements (default, length), then pairs of u4 values.

   110     // So load table length, and compute address at end of table

   111     _pc = (address)&_table_base[2+ 2*Bytes::get_Java_u4((address)&_table_base[1])];

   112     break;

   113 

   114   case Bytecodes::_tableswitch: {

   115     _pc++;                      // Skip wide bytecode

   116     _pc += (_start-_pc)&3;      // Word align

   117     _table_base = (jint*)_pc;   // Capture for later usage

   118                                 // table_base[0] is default far_dest

   119     int lo = Bytes::get_Java_u4((address)&_table_base[1]);// Low bound

   120     int hi = Bytes::get_Java_u4((address)&_table_base[2]);// High bound

   121     int len = hi - lo + 1;      // Dense table size

   122     _pc = (address)&_table_base[3+len]; // Skip past table

   123     break;

   124   }

   125 

   126   default:

   127     fatal("unhandled bytecode");

   128   }

   129   return bc;

   130 }

   131 

   132 // ------------------------------------------------------------------

   133 // ciBytecodeStream::reset_to_bci

   134 void ciBytecodeStream::reset_to_bci( int bci ) {

   135   _bc_start=_was_wide=0;

   136   _pc = _start+bci;

   137 }

   138 

   139 // ------------------------------------------------------------------

   140 // ciBytecodeStream::force_bci

   141 void ciBytecodeStream::force_bci(int bci) {

   142   if (bci < 0) {

   143     reset_to_bci(0);

   144     _bc_start = _start + bci;

   145     _bc = EOBC();

   146   } else {

   147     reset_to_bci(bci);

   148     next();

   149   }

   150 }

   151 

   152 

   153 // ------------------------------------------------------------------

   154 // Constant pool access

   155 // ------------------------------------------------------------------

   156 

   157 // ------------------------------------------------------------------

   158 // ciBytecodeStream::get_klass_index

   159 //

   160 // If this bytecodes references a klass, return the index of the

   161 // referenced klass.

   162 int ciBytecodeStream::get_klass_index() const {

   163   switch(cur_bc()) {

   164   case Bytecodes::_ldc:

   165     return get_index_u1();

   166   case Bytecodes::_ldc_w:

   167   case Bytecodes::_ldc2_w:

   168   case Bytecodes::_checkcast:

   169   case Bytecodes::_instanceof:

   170   case Bytecodes::_anewarray:

   171   case Bytecodes::_multianewarray:

   172   case Bytecodes::_new:

   173   case Bytecodes::_newarray:

   174     return get_index_u2();

   175   default:

   176     ShouldNotReachHere();

   177     return 0;

   178   }

   179 }

   180 

   181 // ------------------------------------------------------------------

   182 // ciBytecodeStream::get_klass

   183 //

   184 // If this bytecode is a new, newarray, multianewarray, instanceof,

   185 // or checkcast, get the referenced klass.

   186 ciKlass* ciBytecodeStream::get_klass(bool& will_link) {

   187   VM_ENTRY_MARK;

   188   constantPoolHandle cpool(_method->get_Method()->constants());

   189   return CURRENT_ENV->get_klass_by_index(cpool, get_klass_index(), will_link, _holder);

   190 }

   191 

   192 // ------------------------------------------------------------------

   193 // ciBytecodeStream::get_constant_raw_index

   194 //

   195 // If this bytecode is one of the ldc variants, get the index of the

   196 // referenced constant.

   197 int ciBytecodeStream::get_constant_raw_index() const {

   198   // work-alike for Bytecode_loadconstant::raw_index()

   199   switch (cur_bc()) {

   200   case Bytecodes::_ldc:

   201     return get_index_u1();

   202   case Bytecodes::_ldc_w:

   203   case Bytecodes::_ldc2_w:

   204     return get_index_u2();

   205   default:

   206     ShouldNotReachHere();

   207     return 0;

   208   }

   209 }

   210 

   211 // ------------------------------------------------------------------

   212 // ciBytecodeStream::get_constant_pool_index

   213 // Decode any reference index into a regular pool index.

   214 int ciBytecodeStream::get_constant_pool_index() const {

   215   // work-alike for Bytecode_loadconstant::pool_index()

   216   int index = get_constant_raw_index();

   217   if (has_cache_index()) {

   218     VM_ENTRY_MARK;

   219     constantPoolHandle cpool(_method->get_Method()->constants());

   220     return cpool->object_to_cp_index(index);

   221   }

   222   return index;

   223 }

   224 

   225 // ------------------------------------------------------------------

   226 // ciBytecodeStream::get_constant_cache_index

   227 // Return the CP cache index, or -1 if there isn't any.

   228 int ciBytecodeStream::get_constant_cache_index() const {

   229   // work-alike for Bytecode_loadconstant::cache_index()

   230   return has_cache_index() ? get_constant_raw_index() : -1;

   231 }

   232 

   233 // ------------------------------------------------------------------

   234 // ciBytecodeStream::get_constant

   235 //

   236 // If this bytecode is one of the ldc variants, get the referenced

   237 // constant.

   238 ciConstant ciBytecodeStream::get_constant() {

   239   int pool_index = get_constant_raw_index();

   240   int cache_index = -1;

   241   if (has_cache_index()) {

   242     cache_index = pool_index;

   243     pool_index = -1;

   244   }

   245   VM_ENTRY_MARK;

   246   constantPoolHandle cpool(_method->get_Method()->constants());

   247   return CURRENT_ENV->get_constant_by_index(cpool, pool_index, cache_index, _holder);

   248 }

   249 

   250 // ------------------------------------------------------------------

   251 // ciBytecodeStream::get_constant_pool_tag

   252 //

   253 // If this bytecode is one of the ldc variants, get the referenced

   254 // constant.

   255 constantTag ciBytecodeStream::get_constant_pool_tag(int index) const {

   256   VM_ENTRY_MARK;

   257   return _method->get_Method()->constants()->tag_at(index);

   258 }

   259 

   260 // ------------------------------------------------------------------

   261 // ciBytecodeStream::get_field_index

   262 //

   263 // If this is a field access bytecode, get the constant pool

   264 // index of the referenced field.

   265 int ciBytecodeStream::get_field_index() {

   266   assert(cur_bc() == Bytecodes::_getfield ||

   267          cur_bc() == Bytecodes::_putfield ||

   268          cur_bc() == Bytecodes::_getstatic ||

   269          cur_bc() == Bytecodes::_putstatic, "wrong bc");

   270   return get_index_u2_cpcache();

   271 }

   272 

   273 

   274 // ------------------------------------------------------------------

   275 // ciBytecodeStream::get_field

   276 //

   277 // If this bytecode is one of get_field, get_static, put_field,

   278 // or put_static, get the referenced field.

   279 ciField* ciBytecodeStream::get_field(bool& will_link) {

   280   ciField* f = CURRENT_ENV->get_field_by_index(_holder, get_field_index());

   281   will_link = f->will_link(_method, _bc);

   282   return f;

   283 }

   284 

   285 

   286 // ------------------------------------------------------------------

   287 // ciBytecodeStream::get_declared_field_holder

   288 //

   289 // Get the declared holder of the currently referenced field.

   290 //

   291 // Usage note: the holder() of a ciField class returns the canonical

   292 // holder of the field, rather than the holder declared in the

   293 // bytecodes.

   294 //

   295 // There is no "will_link" result passed back.  The user is responsible

   296 // for checking linkability when retrieving the associated field.

   297 ciInstanceKlass* ciBytecodeStream::get_declared_field_holder() {

   298   VM_ENTRY_MARK;

   299   constantPoolHandle cpool(_method->get_Method()->constants());

   300   int holder_index = get_field_holder_index();

   301   bool ignore;

   302   return CURRENT_ENV->get_klass_by_index(cpool, holder_index, ignore, _holder)

   303       ->as_instance_klass();

   304 }

   305 

   306 // ------------------------------------------------------------------

   307 // ciBytecodeStream::get_field_holder_index

   308 //

   309 // Get the constant pool index of the declared holder of the field

   310 // referenced by the current bytecode.  Used for generating

   311 // deoptimization information.

   312 int ciBytecodeStream::get_field_holder_index() {

   313   GUARDED_VM_ENTRY(

   314     ConstantPool* cpool = _holder->get_instanceKlass()->constants();

   315     return cpool->klass_ref_index_at(get_field_index());

   316   )

   317 }

   318 

   319 // ------------------------------------------------------------------

   320 // ciBytecodeStream::get_field_signature_index

   321 //

   322 // Get the constant pool index of the signature of the field

   323 // referenced by the current bytecode.  Used for generating

   324 // deoptimization information.

   325 int ciBytecodeStream::get_field_signature_index() {

   326   VM_ENTRY_MARK;

   327   ConstantPool* cpool = _holder->get_instanceKlass()->constants();

   328   int nt_index = cpool->name_and_type_ref_index_at(get_field_index());

   329   return cpool->signature_ref_index_at(nt_index);

   330 }

   331 

   332 // ------------------------------------------------------------------

   333 // ciBytecodeStream::get_method_index

   334 //

   335 // If this is a method invocation bytecode, get the constant pool

   336 // index of the invoked method.

   337 int ciBytecodeStream::get_method_index() {

   338 #ifdef ASSERT

   339   switch (cur_bc()) {

   340   case Bytecodes::_invokeinterface:

   341   case Bytecodes::_invokevirtual:

   342   case Bytecodes::_invokespecial:

   343   case Bytecodes::_invokestatic:

   344   case Bytecodes::_invokedynamic:

   345     break;

   346   default:

   347     ShouldNotReachHere();

   348   }

   349 #endif

   350   if (has_index_u4())

   351     return get_index_u4();  // invokedynamic

   352   return get_index_u2_cpcache();

   353 }

   354 

   355 // ------------------------------------------------------------------

   356 // ciBytecodeStream::get_method

   357 //

   358 // If this is a method invocation bytecode, get the invoked method.

   359 // Additionally return the declared signature to get more concrete

   360 // type information if required (Cf. invokedynamic and invokehandle).

   361 ciMethod* ciBytecodeStream::get_method(bool& will_link, ciSignature* *declared_signature_result) {

   362   VM_ENTRY_MARK;

   363   ciEnv* env = CURRENT_ENV;

   364   constantPoolHandle cpool(THREAD, _method->get_Method()->constants());

   365   ciMethod* m = env->get_method_by_index(cpool, get_method_index(), cur_bc(), _holder);

   366   will_link = m->is_loaded();

   367 

   368   // Use the MethodType stored in the CP cache to create a signature

   369   // with correct types (in respect to class loaders).

   370   if (has_method_type()) {

   371     ciSymbol*     sig_sym     = env->get_symbol(cpool->symbol_at(get_method_signature_index(cpool)));

   372     ciKlass*      pool_holder = env->get_klass(cpool->pool_holder());

   373     ciMethodType* method_type = get_method_type();

   374     ciSignature* declared_signature = new (env->arena()) ciSignature(pool_holder, sig_sym, method_type);

   375     (*declared_signature_result) = declared_signature;

   376   } else {

   377     (*declared_signature_result) = m->signature();

   378   }

   379   return m;

   380 }

   381 

   382 // ------------------------------------------------------------------

   383 // ciBytecodeStream::has_appendix

   384 //

   385 // Returns true if there is an appendix argument stored in the

   386 // constant pool cache at the current bci.

   387 bool ciBytecodeStream::has_appendix() {

   388   VM_ENTRY_MARK;

   389   constantPoolHandle cpool(_method->get_Method()->constants());

   390   return ConstantPool::has_appendix_at_if_loaded(cpool, get_method_index());

   391 }

   392 

   393 // ------------------------------------------------------------------

   394 // ciBytecodeStream::get_appendix

   395 //

   396 // Return the appendix argument stored in the constant pool cache at

   397 // the current bci.

   398 ciObject* ciBytecodeStream::get_appendix() {

   399   VM_ENTRY_MARK;

   400   constantPoolHandle cpool(_method->get_Method()->constants());

   401   oop appendix_oop = ConstantPool::appendix_at_if_loaded(cpool, get_method_index());

   402   return CURRENT_ENV->get_object(appendix_oop);

   403 }

   404 

   405 // ------------------------------------------------------------------

   406 // ciBytecodeStream::has_method_type

   407 //

   408 // Returns true if there is a MethodType argument stored in the

   409 // constant pool cache at the current bci.

   410 bool ciBytecodeStream::has_method_type() {

   411   GUARDED_VM_ENTRY(

   412     constantPoolHandle cpool(_method->get_Method()->constants());

   413     return ConstantPool::has_method_type_at_if_loaded(cpool, get_method_index());

   414   )

   415 }

   416 

   417 // ------------------------------------------------------------------

   418 // ciBytecodeStream::get_method_type

   419 //

   420 // Return the MethodType stored in the constant pool cache at

   421 // the current bci.

   422 ciMethodType* ciBytecodeStream::get_method_type() {

   423   GUARDED_VM_ENTRY(

   424     constantPoolHandle cpool(_method->get_Method()->constants());

   425     oop method_type_oop = ConstantPool::method_type_at_if_loaded(cpool, get_method_index());

   426     return CURRENT_ENV->get_object(method_type_oop)->as_method_type();

   427   )

   428 }

   429 

   430 // ------------------------------------------------------------------

   431 // ciBytecodeStream::get_declared_method_holder

   432 //

   433 // Get the declared holder of the currently referenced method.

   434 //

   435 // Usage note: the holder() of a ciMethod class returns the canonical

   436 // holder of the method, rather than the holder declared in the

   437 // bytecodes.

   438 //

   439 // There is no "will_link" result passed back.  The user is responsible

   440 // for checking linkability when retrieving the associated method.

   441 ciKlass* ciBytecodeStream::get_declared_method_holder() {

   442   VM_ENTRY_MARK;

   443   constantPoolHandle cpool(_method->get_Method()->constants());

   444   bool ignore;

   445   // report as MethodHandle for invokedynamic, which is syntactically classless

   446   if (cur_bc() == Bytecodes::_invokedynamic)

   447     return CURRENT_ENV->get_klass_by_name(_holder, ciSymbol::java_lang_invoke_MethodHandle(), false);

   448   return CURRENT_ENV->get_klass_by_index(cpool, get_method_holder_index(), ignore, _holder);

   449 }

   450 

   451 // ------------------------------------------------------------------

   452 // ciBytecodeStream::get_method_holder_index

   453 //

   454 // Get the constant pool index of the declared holder of the method

   455 // referenced by the current bytecode.  Used for generating

   456 // deoptimization information.

   457 int ciBytecodeStream::get_method_holder_index() {

   458   ConstantPool* cpool = _method->get_Method()->constants();

   459   return cpool->klass_ref_index_at(get_method_index());

   460 }

   461 

   462 // ------------------------------------------------------------------

   463 // ciBytecodeStream::get_method_signature_index

   464 //

   465 // Get the constant pool index of the signature of the method

   466 // referenced by the current bytecode.  Used for generating

   467 // deoptimization information.

   468 int ciBytecodeStream::get_method_signature_index(const constantPoolHandle& cpool) {

   469   GUARDED_VM_ENTRY(

   470     const int method_index = get_method_index();

   471     const int name_and_type_index = cpool->name_and_type_ref_index_at(method_index);

   472     return cpool->signature_ref_index_at(name_and_type_index);

   473   )

   474 }

   475 

   476 // ------------------------------------------------------------------

   477 // ciBytecodeStream::get_resolved_references

   478 ciObjArray* ciBytecodeStream::get_resolved_references() {

   479     VM_ENTRY_MARK;

   480     // Get the constant pool.

   481   ConstantPool*        cpool   = _holder->get_instanceKlass()->constants();

   482 

   483   // Create a resolved references array and return it.

   484   return CURRENT_ENV->get_object(cpool->resolved_references())->as_obj_array();

   485   }