1 /*
   2  * Copyright (c) 1999, 2012, 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(_holder, _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(_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()));
 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() {
 469   GUARDED_VM_ENTRY(
 470     ConstantPool* cpool = _holder->get_instanceKlass()->constants();
 471     const int method_index = get_method_index();
 472     const int name_and_type_index = cpool->name_and_type_ref_index_at(method_index);
 473     return cpool->signature_ref_index_at(name_and_type_index);
 474   )
 475 }
 476 
 477 // ------------------------------------------------------------------
 478 // ciBytecodeStream::get_resolved_references
 479 ciObjArray* ciBytecodeStream::get_resolved_references() {
 480     VM_ENTRY_MARK;
 481     // Get the constant pool.
 482   ConstantPool*        cpool   = _holder->get_instanceKlass()->constants();
 483 
 484   // Create a resolved references array and return it.
 485   return CURRENT_ENV->get_object(cpool->resolved_references())->as_obj_array();
 486   }
--- EOF ---