353 // Rewrites a method given the index_map information |
353 // Rewrites a method given the index_map information |
354 void Rewriter::scan_method(Method* method, bool reverse, bool* invokespecial_error) { |
354 void Rewriter::scan_method(Method* method, bool reverse, bool* invokespecial_error) { |
355 |
355 |
356 int nof_jsrs = 0; |
356 int nof_jsrs = 0; |
357 bool has_monitor_bytecodes = false; |
357 bool has_monitor_bytecodes = false; |
358 |
358 Bytecodes::Code c; |
359 { |
359 |
360 // We cannot tolerate a GC in this block, because we've |
360 // Bytecodes and their length |
361 // cached the bytecodes in 'code_base'. If the Method* |
361 const address code_base = method->code_base(); |
362 // moves, the bytecodes will also move. |
362 const int code_length = method->code_size(); |
363 NoSafepointVerifier nsv; |
363 |
364 Bytecodes::Code c; |
364 int bc_length; |
365 |
365 for (int bci = 0; bci < code_length; bci += bc_length) { |
366 // Bytecodes and their length |
366 address bcp = code_base + bci; |
367 const address code_base = method->code_base(); |
367 int prefix_length = 0; |
368 const int code_length = method->code_size(); |
368 c = (Bytecodes::Code)(*bcp); |
369 |
369 |
370 int bc_length; |
370 // Since we have the code, see if we can get the length |
371 for (int bci = 0; bci < code_length; bci += bc_length) { |
371 // directly. Some more complicated bytecodes will report |
372 address bcp = code_base + bci; |
372 // a length of zero, meaning we need to make another method |
373 int prefix_length = 0; |
373 // call to calculate the length. |
374 c = (Bytecodes::Code)(*bcp); |
374 bc_length = Bytecodes::length_for(c); |
375 |
375 if (bc_length == 0) { |
376 // Since we have the code, see if we can get the length |
376 bc_length = Bytecodes::length_at(method, bcp); |
377 // directly. Some more complicated bytecodes will report |
377 |
378 // a length of zero, meaning we need to make another method |
378 // length_at will put us at the bytecode after the one modified |
379 // call to calculate the length. |
379 // by 'wide'. We don't currently examine any of the bytecodes |
380 bc_length = Bytecodes::length_for(c); |
380 // modified by wide, but in case we do in the future... |
381 if (bc_length == 0) { |
381 if (c == Bytecodes::_wide) { |
382 bc_length = Bytecodes::length_at(method, bcp); |
382 prefix_length = 1; |
383 |
383 c = (Bytecodes::Code)bcp[1]; |
384 // length_at will put us at the bytecode after the one modified |
384 } |
385 // by 'wide'. We don't currently examine any of the bytecodes |
385 } |
386 // modified by wide, but in case we do in the future... |
386 |
387 if (c == Bytecodes::_wide) { |
387 assert(bc_length != 0, "impossible bytecode length"); |
388 prefix_length = 1; |
388 |
389 c = (Bytecodes::Code)bcp[1]; |
389 switch (c) { |
390 } |
390 case Bytecodes::_lookupswitch : { |
391 } |
|
392 |
|
393 assert(bc_length != 0, "impossible bytecode length"); |
|
394 |
|
395 switch (c) { |
|
396 case Bytecodes::_lookupswitch : { |
|
397 #ifndef CC_INTERP |
391 #ifndef CC_INTERP |
398 Bytecode_lookupswitch bc(method, bcp); |
392 Bytecode_lookupswitch bc(method, bcp); |
399 (*bcp) = ( |
393 (*bcp) = ( |
400 bc.number_of_pairs() < BinarySwitchThreshold |
394 bc.number_of_pairs() < BinarySwitchThreshold |
401 ? Bytecodes::_fast_linearswitch |
395 ? Bytecodes::_fast_linearswitch |
402 : Bytecodes::_fast_binaryswitch |
396 : Bytecodes::_fast_binaryswitch |
403 ); |
397 ); |
404 #endif |
398 #endif |
405 break; |
399 break; |
406 } |
400 } |
407 case Bytecodes::_fast_linearswitch: |
401 case Bytecodes::_fast_linearswitch: |
408 case Bytecodes::_fast_binaryswitch: { |
402 case Bytecodes::_fast_binaryswitch: { |
409 #ifndef CC_INTERP |
403 #ifndef CC_INTERP |
410 (*bcp) = Bytecodes::_lookupswitch; |
404 (*bcp) = Bytecodes::_lookupswitch; |
411 #endif |
405 #endif |
412 break; |
406 break; |
413 } |
407 } |
414 |
408 |
415 case Bytecodes::_invokespecial : { |
409 case Bytecodes::_invokespecial : { |
416 rewrite_invokespecial(bcp, prefix_length+1, reverse, invokespecial_error); |
410 rewrite_invokespecial(bcp, prefix_length+1, reverse, invokespecial_error); |
417 break; |
411 break; |
418 } |
412 } |
419 |
413 |
420 case Bytecodes::_putstatic : |
414 case Bytecodes::_putstatic : |
421 case Bytecodes::_putfield : { |
415 case Bytecodes::_putfield : { |
422 if (!reverse) { |
416 if (!reverse) { |
423 // Check if any final field of the class given as parameter is modified |
417 // Check if any final field of the class given as parameter is modified |
424 // outside of initializer methods of the class. Fields that are modified |
418 // outside of initializer methods of the class. Fields that are modified |
425 // are marked with a flag. For marked fields, the compilers do not perform |
419 // are marked with a flag. For marked fields, the compilers do not perform |
426 // constant folding (as the field can be changed after initialization). |
420 // constant folding (as the field can be changed after initialization). |
427 // |
421 // |
428 // The check is performed after verification and only if verification has |
422 // The check is performed after verification and only if verification has |
429 // succeeded. Therefore, the class is guaranteed to be well-formed. |
423 // succeeded. Therefore, the class is guaranteed to be well-formed. |
430 InstanceKlass* klass = method->method_holder(); |
424 InstanceKlass* klass = method->method_holder(); |
431 u2 bc_index = Bytes::get_Java_u2(bcp + prefix_length + 1); |
425 u2 bc_index = Bytes::get_Java_u2(bcp + prefix_length + 1); |
432 constantPoolHandle cp(method->constants()); |
426 constantPoolHandle cp(method->constants()); |
433 Symbol* ref_class_name = cp->klass_name_at(cp->klass_ref_index_at(bc_index)); |
427 Symbol* ref_class_name = cp->klass_name_at(cp->klass_ref_index_at(bc_index)); |
434 |
428 |
435 if (klass->name() == ref_class_name) { |
429 if (klass->name() == ref_class_name) { |
436 Symbol* field_name = cp->name_ref_at(bc_index); |
430 Symbol* field_name = cp->name_ref_at(bc_index); |
437 Symbol* field_sig = cp->signature_ref_at(bc_index); |
431 Symbol* field_sig = cp->signature_ref_at(bc_index); |
438 |
432 |
439 fieldDescriptor fd; |
433 fieldDescriptor fd; |
440 if (klass->find_field(field_name, field_sig, &fd) != NULL) { |
434 if (klass->find_field(field_name, field_sig, &fd) != NULL) { |
441 if (fd.access_flags().is_final()) { |
435 if (fd.access_flags().is_final()) { |
442 if (fd.access_flags().is_static()) { |
436 if (fd.access_flags().is_static()) { |
443 if (!method->is_static_initializer()) { |
437 if (!method->is_static_initializer()) { |
444 fd.set_has_initialized_final_update(true); |
438 fd.set_has_initialized_final_update(true); |
445 } |
439 } |
446 } else { |
440 } else { |
447 if (!method->is_object_initializer()) { |
441 if (!method->is_object_initializer()) { |
448 fd.set_has_initialized_final_update(true); |
442 fd.set_has_initialized_final_update(true); |
449 } |
|
450 } |
443 } |
451 } |
444 } |
452 } |
445 } |
453 } |
446 } |
454 } |
447 } |
455 } |
448 } |
456 // fall through |
449 } |
457 case Bytecodes::_getstatic : // fall through |
450 // fall through |
458 case Bytecodes::_getfield : // fall through |
451 case Bytecodes::_getstatic : // fall through |
459 case Bytecodes::_invokevirtual : // fall through |
452 case Bytecodes::_getfield : // fall through |
460 case Bytecodes::_invokestatic : |
453 case Bytecodes::_invokevirtual : // fall through |
461 case Bytecodes::_invokeinterface: |
454 case Bytecodes::_invokestatic : |
462 case Bytecodes::_invokehandle : // if reverse=true |
455 case Bytecodes::_invokeinterface: |
463 rewrite_member_reference(bcp, prefix_length+1, reverse); |
456 case Bytecodes::_invokehandle : // if reverse=true |
464 break; |
457 rewrite_member_reference(bcp, prefix_length+1, reverse); |
465 case Bytecodes::_invokedynamic: |
458 break; |
466 rewrite_invokedynamic(bcp, prefix_length+1, reverse); |
459 case Bytecodes::_invokedynamic: |
467 break; |
460 rewrite_invokedynamic(bcp, prefix_length+1, reverse); |
468 case Bytecodes::_ldc: |
461 break; |
469 case Bytecodes::_fast_aldc: // if reverse=true |
462 case Bytecodes::_ldc: |
470 maybe_rewrite_ldc(bcp, prefix_length+1, false, reverse); |
463 case Bytecodes::_fast_aldc: // if reverse=true |
471 break; |
464 maybe_rewrite_ldc(bcp, prefix_length+1, false, reverse); |
472 case Bytecodes::_ldc_w: |
465 break; |
473 case Bytecodes::_fast_aldc_w: // if reverse=true |
466 case Bytecodes::_ldc_w: |
474 maybe_rewrite_ldc(bcp, prefix_length+1, true, reverse); |
467 case Bytecodes::_fast_aldc_w: // if reverse=true |
475 break; |
468 maybe_rewrite_ldc(bcp, prefix_length+1, true, reverse); |
476 case Bytecodes::_jsr : // fall through |
469 break; |
477 case Bytecodes::_jsr_w : nof_jsrs++; break; |
470 case Bytecodes::_jsr : // fall through |
478 case Bytecodes::_monitorenter : // fall through |
471 case Bytecodes::_jsr_w : nof_jsrs++; break; |
479 case Bytecodes::_monitorexit : has_monitor_bytecodes = true; break; |
472 case Bytecodes::_monitorenter : // fall through |
480 |
473 case Bytecodes::_monitorexit : has_monitor_bytecodes = true; break; |
481 default: break; |
474 |
482 } |
475 default: break; |
483 } |
476 } |
484 } |
477 } |
485 |
478 |
486 // Update access flags |
479 // Update access flags |
487 if (has_monitor_bytecodes) { |
480 if (has_monitor_bytecodes) { |