static bool NextCmp( instruction *ins ) {
/*********************************************/
instruction *next;
next = ins->head.next;
if( !_OpIsCondition( next->head.opcode ) ) return( FALSE );
if( next->table == DoNop ) return( TRUE );
if( next->u.gen_table == NULL ) return( FALSE );
if( next->u.gen_table->generate != G_NO ) return( FALSE );
return( TRUE );
}
static instruction *FindOneCond( block *blk )
/************************************************/
{
instruction *ins;
instruction *cond;
cond = NULL;
for( ins = blk->ins.hd.next; ins->head.opcode != OP_BLOCK; ins = ins->head.next ) {
if( _OpIsCondition( ins->head.opcode ) ) {
if( cond != NULL ) return( NULL );
cond = ins;
}
}
return( cond );
}
static bool isNiceCondIns( instruction *ins )
/************************************************
* Figure out if an instruction can be converted to OP_SET_LESS
*/
{
opcode_defs oc;
oc = ins->head.opcode;
if( !_OpIsCondition( oc ) )
return( FALSE );
if( oc == OP_CMP_LESS || oc == OP_CMP_GREATER )
return( TRUE );
if( (oc == OP_CMP_LESS_EQUAL) && (ins->operands[1]->n.class == N_CONSTANT)
&& (ins->operands[1]->c.const_type == CONS_ABSOLUTE) )
return( TRUE );
if( (oc == OP_CMP_GREATER_EQUAL) && (ins->operands[1]->n.class == N_CONSTANT)
&& (ins->operands[1]->c.const_type == CONS_ABSOLUTE) )
return( TRUE );
return( FALSE );
}
/* Take advantage of the SETcc instruction in cases such as
* x = y ? 3 : 4;
* by adding a constant to the result of SETcc to directly obtain
* the result of the assignment.
*/
static bool FindFlowOut( block *blk ) {
/*****************************************/
signed_64 false_cons;
signed_64 true_cons;
signed_64 one;
signed_64 neg_one;
signed_64 diff;
instruction *ins;
instruction *ins0;
instruction *ins1;
// instruction *prev;
block *true_blk;
block *false_blk;
block *join_blk;
block_edge *new_edge;
bool reverse;
name *u1temp;
name *temp;
name *result;
name *konst;
type_class_def class;
for( ins = blk->ins.hd.prev; !_OpIsCondition( ins->head.opcode ); ) {
ins = ins->head.prev;
}
// prev = ins->head.prev;
if( TypeClassSize[ ins->type_class ] > WORD_SIZE ) return( FALSE );
true_blk = blk->edge[ _TrueIndex( ins ) ].destination.u.blk;
if( true_blk->inputs != 1 ) return( FALSE );
if( true_blk->targets != 1 ) return( FALSE );
false_blk = blk->edge[ _FalseIndex( ins ) ].destination.u.blk;
if( false_blk->inputs != 1 ) return( FALSE );
if( false_blk->targets != 1 ) return( FALSE );
join_blk = false_blk->edge[ 0 ].destination.u.blk;
if( join_blk != true_blk->edge[ 0 ].destination.u.blk ) return( FALSE );
if( join_blk->inputs != 2 ) return( FALSE );
if( join_blk->class & UNKNOWN_DESTINATION ) return( FALSE );
ins0 = SetToConst( false_blk, &false_cons );
if( ins0 == NULL ) return( FALSE );
ins1 = SetToConst( true_blk, &true_cons );
if( ins1 == NULL ) return( FALSE );
I32ToI64( 1, &one );
I32ToI64( -1, &neg_one );
U64Sub( &true_cons, &false_cons, &diff );
if( U64Cmp( &diff, &neg_one ) == 0 ) {
U64IncDec( &false_cons, -1 );
reverse = TRUE;
} else {
if( U64Cmp( &diff, &one ) != 0 ) return( FALSE );
reverse = FALSE;
}
result = ins0->result;
if( result != ins1->result ) return( FALSE );
class = ins0->type_class;
if( class != ins1->type_class ) return( FALSE );
if( reverse ) FlipCond( ins );
u1temp = AllocTemp( U1 );
temp = AllocTemp( class );
ins->result = u1temp;
ins1 = MakeConvert( u1temp, temp, class, U1 );
SuffixIns( ins, ins1 );
ins = ins1;
if( I64Test( &false_cons ) != 0 ) {
konst = AllocS64Const( false_cons.u._32[I64LO32], false_cons.u._32[I64HI32] );
ins1 = MakeBinary( OP_ADD, temp, konst, result, class );
} else {
static bool FindFlowOut( block *blk )
/***************************************/
{
signed_32 false_cons;
signed_32 true_cons;
instruction *ins;
instruction *ins0;
instruction *ins1;
block *true;
block *false;
block *join;
block_edge *new_edge;
bool reverse;
name *u4temp;
name *temp;
name *result;
type_class_def class;
opcode_defs oc;
ins = blk->ins.hd.prev;
while( !_OpIsCondition( ins->head.opcode ) ) {
ins = ins->head.prev;
}
if( !isNiceCondIns( ins ) )
return( FALSE );
if( TypeClassSize[ ins->type_class ] > WORD_SIZE )
return( FALSE );
true = blk->edge[ _TrueIndex( ins ) ].destination.u.blk;
if( true->inputs != 1 )
return( FALSE );
if( true->targets != 1 )
return( FALSE );
false = blk->edge[ _FalseIndex( ins ) ].destination.u.blk;
if( false->inputs != 1 )
return( FALSE );
if( false->targets != 1 )
return( FALSE );
join = false->edge[0].destination.u.blk;
if( join != true->edge[0].destination.u.blk )
return( FALSE );
if( join->inputs != 2 )
return( FALSE );
if( join->class & UNKNOWN_DESTINATION )
return( FALSE );
ins0 = SetToConst( false, &false_cons );
if( ins0 == NULL )
return( FALSE );
ins1 = SetToConst( true, &true_cons );
if( ins1 == NULL )
return( FALSE );
if( true_cons - false_cons == -1 ) {
true_cons = false_cons;
false_cons = true_cons - 1;
reverse = TRUE;
} else {
if( true_cons - false_cons != 1 )
return( FALSE );
reverse = FALSE;
}
result = ins0->result;
if( result != ins1->result )
return( FALSE );
class = ins0->type_class;
if( class != ins1->type_class )
return( FALSE );
oc = ins->head.opcode;
if( oc == OP_CMP_GREATER || oc == OP_CMP_GREATER_EQUAL )
reverse = !reverse;
/* Replace 'x <= const' with 'x < const + 1' */
if( oc == OP_CMP_LESS_EQUAL || oc == OP_CMP_GREATER_EQUAL ) {
signed_32 value;
name *op1;
op1 = ins->operands[1];
assert( op1->n.class == N_CONSTANT && op1->c.const_type == CONS_ABSOLUTE );
value = op1->c.int_value;
if( oc == OP_CMP_LESS_EQUAL )
value += 1;
else
value -= 1;
ins->operands[1] = AllocS32Const( value );
}
instruction *rMAKECALL( instruction *ins )
/*********************************************
Using the table RTInfo[], do all the necessary stuff to turn
instruction "ins" into a call to a runtime support routine. Move
the parms into registers, and move the return register of the
runtime routine into the result. Used for 386 and 370 versions
*/
{
rtn_info *info;
label_handle lbl;
instruction *left_ins;
instruction *new_ins;
instruction *last_ins;
name *reg_name;
hw_reg_set regs;
hw_reg_set all_regs;
hw_reg_set tmp;
rt_class rtindex;
if( !_IsConvert( ins ) ) {
rtindex = LookupRoutine( ins );
} else { /* look it up again in case we ran out of memory during expansion*/
rtindex = LookupConvertRoutine( ins );
}
info = &RTInfo[rtindex];
regs = _ParmReg( info->left );
all_regs = regs;
left_ins = MakeMove( ins->operands[0], AllocRegName( regs ),
info->operand_class );
ins->operands[0] = left_ins->result;
MoveSegOp( ins, left_ins, 0 );
PrefixIns( ins, left_ins );
regs = _ParmReg( info->right );
if( !HW_CEqual( regs, HW_EMPTY ) ) {
new_ins = MakeMove( ins->operands[1], AllocRegName( regs ),
info->operand_class );
ins->operands[1] = new_ins->result;
MoveSegOp( ins, new_ins, 0 );
HW_TurnOn( all_regs, regs );
PrefixIns( ins, new_ins );
}
#if _TARGET & _TARG_370
tmp = RAReg();
HW_TurnOn( all_regs, tmp );
tmp = LNReg();
HW_TurnOn( all_regs, tmp );
#elif _TARGET & _TARG_80386
{
tmp = ReturnReg( WD, false );
HW_TurnOn( all_regs, tmp );
}
#endif
reg_name = AllocRegName( all_regs );
lbl = RTLabel( rtindex );
new_ins = NewIns( 3 );
new_ins->head.opcode = OP_CALL;
new_ins->type_class = ins->type_class;
new_ins->operands[CALL_OP_USED] = reg_name;
new_ins->operands[CALL_OP_USED2] = reg_name;
new_ins->operands[CALL_OP_ADDR] = AllocMemory( lbl, 0, CG_LBL, ins->type_class );
new_ins->result = NULL;
new_ins->num_operands = 2; /* special case for OP_CALL*/
#if _TARGET & _TARG_AXP
{
HW_CTurnOn( all_regs, HW_FULL );
HW_TurnOff( all_regs, SavedRegs() );
HW_CTurnOff( all_regs, HW_UNUSED );
HW_TurnOn( all_regs, ReturnAddrReg() );
}
#endif
new_ins->zap = (register_name *)AllocRegName( all_regs ); /* all parm regs could be zapped*/
last_ins = new_ins;
if( ins->result == NULL || _OpIsCondition( ins->head.opcode ) ) {
/* comparison, still need conditional jumps*/
ins->operands[0] = AllocIntConst( 0 );
ins->operands[1] = AllocIntConst( 1 );
DelSeg( ins );
DoNothing( ins ); /* just conditional jumps for ins*/
PrefixIns( ins, new_ins );
new_ins->ins_flags |= INS_CC_USED;
last_ins = ins;
} else {
regs = _ParmReg( info->result );
tmp = regs;
HW_TurnOn( tmp, new_ins->zap->reg );
new_ins->zap = (register_name *)AllocRegName( tmp );
reg_name = AllocRegName( regs );
new_ins->result = reg_name;
last_ins = MakeMove( reg_name, ins->result, ins->type_class );
ins->result = last_ins->operands[0];
MoveSegRes( ins, last_ins );
SuffixIns( ins, last_ins );
ReplIns( ins, new_ins );
}
FixCallIns( new_ins );
UpdateLive( left_ins, last_ins );
return( left_ins );
}