lestes::backend_v2::workers::useless_code_eliminator Class Reference

Removes useless code from a function body. More...

#include <useless_code_eliminator.g.hh>

Inheritance diagram for lestes::backend_v2::workers::useless_code_eliminator:

List of all members.

Public Member Functions
void	process ()
	Eliminates a uselesss code.
ptr< ::lestes::backend_v2::structs::func_data >	get_result ()
	Returns data of a currently processed function without a useless code.
void	set_register_user (ulint reg_id, ptr< ::lestes::backend_v2::intercode::pi_mem_factory > user, ptr< map< ulint, srp< ::lestes::backend_v2::intercode::pi_mem_factory > > > reg2user)
virtual ptr< reflection_list >	reflection_get () const
	for purposes of dumping
virtual ptr< field_list_list >	field_values_get () const
	for purposes of dumping
Static Public Member Functions
static ptr< useless_code_eliminator >	create (ptr< ::lestes::backend_v2::structs::func_data > a__worker_base__data)
	First generated factory method for class useless_code_eliminator.
Protected Member Functions
	useless_code_eliminator (ptr< ::lestes::backend_v2::structs::func_data > a__worker_base__data)
	Generated constructor for class useless_code_eliminator.
virtual void	gc_mark ()
	Marking routine for class useless_code_eliminator.
Static Private Attributes
static ptr< reflection_list >	reflection = reflection

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Detailed Description

Removes useless code from a function body.

Definition at line 41 of file useless_code_eliminator.g.hh.

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Constructor & Destructor Documentation

lestes::backend_v2::workers::useless_code_eliminator::useless_code_eliminator

(

ptr< ::lestes::backend_v2::structs::func_data >

a__worker_base__data

)

[protected]

Generated constructor for class useless_code_eliminator.

Generated constructor for class useless_code_eliminator.

Author:

lsg

Definition at line 37 of file useless_code_eliminator.g.cc.

Referenced by create().

        : worker_base(a__worker_base__data)
{}

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Member Function Documentation

void lestes::backend_v2::workers::useless_code_eliminator::process

(

)

[virtual]

Eliminates a uselesss code.

Implements lestes::backend_v2::workers::worker_base.

Definition at line 29 of file useless_code_eliminator.cc.

References lestes::backend_v2::workers::worker_base::data_get(), lassert, and set_register_user().

                                      {
        
        ptr<ge_pi_list__type> body = data_get()->ge_body_get();

        ptr<id2mf__type> reg2mem = id2mf__type::create();
                
        for(ge_pi_list__type::iterator it = body->begin(); it!=body->end(); ++it) {
                
                ptr<ge_pi> ge = *it;
                
                ptr<tm_instr_base> tm = ge->instruction_get();
                
                if ( ge->kind_get()==ge_pi::SP && ge.dncast<ge_sp>()->is_jmp_target_get() ) {
                        //Instruction invalidates reg2mem mapping.
                        reg2mem->clear();
                        continue;
                }
                
                if ( !tm ) {
                        continue;
                }
                
                if ( tm->is_system() ) {
                        //Instruction invalidates reg2mem mapping.
                        reg2mem->clear();
                } else if ( tm->is_copy() ) {
                        ptr<ge_operand_reg> in = ge->operands_input_get()->front().dncast<ge_operand_reg>();
                        ptr<ge_operand_reg> out = ge->operands_output_get()->front().dncast<ge_operand_reg>();
                        ulint assigned_reg1 = (*in->assigned_registers_get())[ge];
                        ulint assigned_reg2 = (*out->assigned_registers_get())[ge];
                        
                        if ( assigned_reg1==assigned_reg2 ) {
                                 //Move eax,eax
                                 //Erase output.         
                                 ge->instruction_set(NULL);
                        }
                        
                        set_register_user(assigned_reg2,(*reg2mem)[assigned_reg1],reg2mem);
                } else if ( tm->is_load() && ge->operands_input_get()->size()==1 ) {
                        //Instruction is load but it's not indirect load.
                        ptr<ge_operand> in = ge->operands_input_get()->front();
                        ptr<ge_operand> out = ge->operands_output_get()->front();
                        
                        if ( out->kind_get()==ge_operand::REGISTER ) {
                                ptr<ge_operand_reg> reg = out.dncast<ge_operand_reg>();
                                ulint assigned_reg = (*reg->assigned_registers_get())[ge];
                        
                                if ( in->kind_get()==ge_operand::MEMORY ) {
                                        ptr<pi_mem_factory> mf = in.dncast<ge_operand_mem>()->factory_get();
                                
                                        if ( mf && (*reg2mem)[assigned_reg]==mf ) {
                                                //The register already contains the mem's value. No load needed.
                                                ge->instruction_set(NULL);      
                                        } else {
                                                //Set flag that the mem's value has been loaded to the reg.
                                                set_register_user(assigned_reg,mf,reg2mem);
                                        }
                                } else if ( in->kind_get()==ge_operand::IMMEDIATE ) {
                                        set_register_user(assigned_reg,NULL,reg2mem);
                                } else lassert(false);
                        }
                        
                } else if ( tm->is_store() && ge->operands_input_get()->size()==1 ) {
                        //Instruction is store but it's not indirect store.
                        ptr<ge_operand> in = ge->operands_input_get()->front();
                        ptr<ge_operand> out = ge->operands_output_get()->front();
                        
                        if ( out->kind_get()==ge_operand::MEMORY && in->kind_get()==ge_operand::REGISTER) {                     
                                //Set flag that the the reg's value has been stored to the mem.
                                set_register_user((*in.dncast<ge_operand_reg>()->assigned_registers_get())[ge],out.dncast<ge_operand_mem>()->factory_get(),reg2mem);
                        } else lassert(false);
                } else {
                        ptr<ge_operand_vector__type> operands = ge->operands_output_get();
                        
                        for(ge_operand_vector__type::iterator it_operand = operands->begin(); it_operand!=operands->end(); ++it_operand) {
                                if ( (*it_operand)->kind_get()!=ge_operand::REGISTER ) {
                                        continue;
                                }
                                
                                ptr<ge_operand_reg> op = (*it_operand).dncast<ge_operand_reg>();
                                ulint assigned_reg = (*op->assigned_registers_get())[ge];
                                
                                set_register_user(assigned_reg,NULL,reg2mem);
                        }
                }
        }
}

ptr< func_data > lestes::backend_v2::workers::useless_code_eliminator::get_result

(

)

[virtual]

Returns data of a currently processed function without a useless code.

Implements lestes::backend_v2::workers::worker_base.

Definition at line 136 of file useless_code_eliminator.cc.

References lestes::backend_v2::workers::worker_base::data_get().

                                                   {
        return data_get();
}

void lestes::backend_v2::workers::useless_code_eliminator::set_register_user	(	ulint	reg_id,
		ptr< ::lestes::backend_v2::intercode::pi_mem_factory >	user,
		ptr< map< ulint, srp< ::lestes::backend_v2::intercode::pi_mem_factory > > >	reg2user
	)

Referenced by process().

ptr< useless_code_eliminator > lestes::backend_v2::workers::useless_code_eliminator::create

(

ptr< ::lestes::backend_v2::structs::func_data >

a__worker_base__data

)

[static]

First generated factory method for class useless_code_eliminator.

This factory method for class useless_code_eliminator takes values of all fields as arguments.

Author:

lsg

Definition at line 28 of file useless_code_eliminator.g.cc.

References useless_code_eliminator().

{
        return ptr< useless_code_eliminator > ( new useless_code_eliminator(a__worker_base__data) );
}

ptr< object::reflection_list > lestes::backend_v2::workers::useless_code_eliminator::reflection_get

(

)

const [virtual]

for purposes of dumping

Reimplemented from lestes::backend_v2::workers::worker_base.

Definition at line 41 of file useless_code_eliminator.g.cc.

References lestes::std::list< T >::create(), reflection, and lestes::backend_v2::workers::worker_base::reflection_get().

{
        if (!reflection) {
                typedef class_reflection::field_metadata md;
                typedef class_reflection::field_metadata_list mdlist;
                ptr<mdlist> mdl = mdlist::create();
                reflection = reflection_list::create( worker_base::reflection_get() );
                reflection->push_back( class_reflection::create( "useless_code_eliminator", mdl ) );
        }
        return reflection;
}

ptr< object::field_list_list > lestes::backend_v2::workers::useless_code_eliminator::field_values_get

(

)

const [virtual]

for purposes of dumping

Reimplemented from lestes::backend_v2::workers::worker_base.

Definition at line 53 of file useless_code_eliminator.g.cc.

References lestes::backend_v2::workers::worker_base::field_values_get().

{
        ptr < field_list_list > result = worker_base::field_values_get();
        return result;
}

void lestes::backend_v2::workers::useless_code_eliminator::gc_mark

(

void

)

[protected, virtual]

Marking routine for class useless_code_eliminator.

Marking routine is used for garbage collection.

Author:

lsg

Reimplemented from lestes::backend_v2::workers::worker_base.

Definition at line 64 of file useless_code_eliminator.g.cc.

References lestes::backend_v2::workers::worker_base::gc_mark().

{
        worker_base::gc_mark();
}

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Member Data Documentation

ptr< object::reflection_list > lestes::backend_v2::workers::useless_code_eliminator::reflection = reflection [static, private]

Reimplemented from lestes::backend_v2::workers::worker_base.

Definition at line 70 of file useless_code_eliminator.g.hh.

Referenced by reflection_get().

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The documentation for this class was generated from the following files:

• useless_code_eliminator.g.hh
• useless_code_eliminator.cc
• useless_code_eliminator.g.cc

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