static bool JustMoveLabel( common_info *max, ins_entry *ins )
/***************************************************************/
{
oc_class cl;
ins_entry *lbl;
ins_entry *add;
ins_entry *next;
optbegin
if( PrevClass( max->start_del ) != OC_LABEL )
optreturn( FALSE );
lbl = PrevIns( max->start_del );
if( _Attr( lbl ) & ATTR_SHORT )
optreturn( FALSE );
cl = PrevClass( lbl );
if( !_TransferClass( cl ) )
optreturn( FALSE );
DeleteQueue( lbl );
InsertQueue( lbl, PrevIns( max->start_com ) );
add = PrevIns( max->start_del );
for( ;; ) {
next = NextIns( add );
DelInstr( next );
if( next == ins ) {
break;
}
}
Untangle( lbl );
optreturn( TRUE );
}
extern ins_entry *IsolatedCode( ins_entry *instr )
/*******************************************************/
{
ins_entry *next;
optbegin
next = NextIns( instr );
for( ;; ) {
if( next == NULL )
optreturn( next );
if( _Class( next ) == OC_LABEL )
break;
_Savings( OPT_ISOLATED, _ObjLen( next ) );
if( _Class( next ) == OC_INFO ) {
next = next->ins.next;
} else {
next = DelInstr( next );
}
if( _Class( instr ) == OC_DEAD ) {
break;
}
}
next = Untangle( next );
optreturn( next );
}
static void TransformJumps( ins_entry *ins, ins_entry *first )
/****************************************************************/
{
ins_entry *add;
ins_entry *next;
ins_entry *lbl;
oc_class cl;
optbegin
if( _Class( ins ) == OC_RET )
optreturnvoid;
lbl = _Label( ins )->ins;
if( lbl == NULL )
optreturnvoid;
add = lbl;
for( ;; ) {
if( add == NULL )
optreturnvoid;
cl = _Class( add );
if( _TransferClass( cl ) )
break;
if( cl == OC_LABEL ) {
if( _Attr( add ) & ATTR_SHORT )
optreturnvoid;
_ClrStatus( _Label( add ), SHORTREACH );
}
add = NextIns( add );
}
if( add == first || add == ins )
optreturnvoid;
if( FindShort( first, lbl ) )
optreturnvoid;
for( ;; ) {
next = PrevIns( add );
DeleteQueue( add );
InsertQueue( add, first );
if( add == lbl )
break;
add = next;
}
DeleteQueue( first );
InsertQueue( first, next );
Untangle( NextIns( first ) );
optend
}
extern bool StraightenCode( ins_entry *jump )
/***********************************************/
{
ins_entry *next;
ins_entry *insert;
ins_entry *hoist;
ins_entry *end_hoist;
oc_class cl;
obj_length align;
optbegin
hoist = _Label( jump )->ins;
if( hoist == NULL )
optreturn( false );
if( hoist == LastIns )
optreturn( false );
cl = PrevClass( hoist );
if( !_TransferClass( cl ) )
optreturn( false );
end_hoist = NULL;
for( next = hoist; ; next = NextIns( next ) ) {
if( next == jump ) { // pushing code down to jump
if( end_hoist == NULL )
optreturn( false );
if( FindShort( hoist, end_hoist ) )
optreturn( false );
break;
}
if( next == NULL ) { // hauling code up to jump
if( FindShort( jump, hoist ) )
optreturn( false );
break;
}
cl = _Class( next );
if( end_hoist == NULL && _TransferClass( cl ) ) {
end_hoist = next;
}
}
align = _ObjLen( hoist );
insert = jump;
for( ;; ) {
if( hoist == NULL ) {
ChgLblRef( jump, AddNewLabel( LastIns, align ) );
next = LastIns;
break;
}
next = NextIns( hoist );
DeleteQueue( hoist );
InsertQueue( hoist, insert );
if( hoist == jump )
optreturn( false );
insert = hoist;
cl = _Class( hoist );
if( _TransferClass( cl ) ) {
IsolatedCode( insert );
break;
}
hoist = next;
}
InsDelete = true;
Untangle( next );
if( _Class( jump ) != OC_DEAD ) {
Untangle( _Label( jump )->ins );
}
optreturn( true );
}
