519 
 520 // Check if a simple chain rule
 521 bool InstructForm::is_simple_chain_rule(FormDict &globals) const {
 522   if( _matrule && _matrule->sets_result()
 523       && _matrule->_rChild->_lChild == NULL
 524       && globals[_matrule->_rChild->_opType]
 525       && globals[_matrule->_rChild->_opType]->is_opclass() ) {
 526     return true;
 527   }
 528   return false;
 529 }
 530 
 531 // check for structural rematerialization
 532 bool InstructForm::rematerialize(FormDict &globals, RegisterForm *registers ) {
 533   bool   rematerialize = false;
 534 
 535   Form::DataType data_type = is_chain_of_constant(globals);
 536   if( data_type != Form::none )
 537     rematerialize = true;
 538 
 539   // Ugly: until a better fix is implemented, disable rematerialization for
 540   // negD nodes because they are proved to be problematic.
 541   if (is_ideal_negD()) {
 542     return false;
 543   }
 544 
 545   // Constants
 546   if( _components.count() == 1 && _components[0]->is(Component::USE_DEF) )
 547     rematerialize = true;
 548 
 549   // Pseudo-constants (values easily available to the runtime)
 550   if (is_empty_encoding() && is_tls_instruction())
 551     rematerialize = true;
 552 
 553   // 1-input, 1-output, such as copies or increments.
 554   if( _components.count() == 2 &&
 555       _components[0]->is(Component::DEF) &&
 556       _components[1]->isa(Component::USE) )
 557     rematerialize = true;
 558 
 559   // Check for an ideal 'Load?' and eliminate rematerialize option
 560   if ( is_ideal_load() != Form::none || // Ideal load?  Do not rematerialize
 561        is_ideal_copy() != Form::none || // Ideal copy?  Do not rematerialize
 562        is_expensive()  != Form::none) { // Expensive?   Do not rematerialize
 563     rematerialize = false;
 564   }

 519 
 520 // Check if a simple chain rule
 521 bool InstructForm::is_simple_chain_rule(FormDict &globals) const {
 522   if( _matrule && _matrule->sets_result()
 523       && _matrule->_rChild->_lChild == NULL
 524       && globals[_matrule->_rChild->_opType]
 525       && globals[_matrule->_rChild->_opType]->is_opclass() ) {
 526     return true;
 527   }
 528   return false;
 529 }
 530 
 531 // check for structural rematerialization
 532 bool InstructForm::rematerialize(FormDict &globals, RegisterForm *registers ) {
 533   bool   rematerialize = false;
 534 
 535   Form::DataType data_type = is_chain_of_constant(globals);
 536   if( data_type != Form::none )
 537     rematerialize = true;
 538 






 539   // Constants
 540   if( _components.count() == 1 && _components[0]->is(Component::USE_DEF) )
 541     rematerialize = true;
 542 
 543   // Pseudo-constants (values easily available to the runtime)
 544   if (is_empty_encoding() && is_tls_instruction())
 545     rematerialize = true;
 546 
 547   // 1-input, 1-output, such as copies or increments.
 548   if( _components.count() == 2 &&
 549       _components[0]->is(Component::DEF) &&
 550       _components[1]->isa(Component::USE) )
 551     rematerialize = true;
 552 
 553   // Check for an ideal 'Load?' and eliminate rematerialize option
 554   if ( is_ideal_load() != Form::none || // Ideal load?  Do not rematerialize
 555        is_ideal_copy() != Form::none || // Ideal copy?  Do not rematerialize
 556        is_expensive()  != Form::none) { // Expensive?   Do not rematerialize
 557     rematerialize = false;
 558   }