/**
* Optimize a given node
*
* @param xp.compiler.ast.Node in
* @param xp.compiler.types.Scope scope
* @param xp.compiler.optimize.Optimizations optimizations
* @param xp.compiler.ast.Node optimized
*/
public function optimize(\xp\compiler\ast\Node $in, \xp\compiler\types\Scope $scope, Optimizations $optimizations)
{
$assign = cast($in, 'xp.compiler.ast.AssignmentNode');
$assign->expression = $optimizations->optimize($assign->expression, $scope);
// Optimize "<var>= <var>+ <expr>" to "<var>+= <expr>"
if ($assign->expression instanceof BinaryOpNode && isset(self::$optimizable[$assign->expression->op]) && $assign->variable->equals($assign->expression->lhs)) {
$assign = new AssignmentNode(['variable' => $assign->variable, 'expression' => $assign->expression->rhs, 'op' => self::$optimizable[$assign->expression->op]]);
}
// Optimize "<var>-= -<expr>" to "<var>+= <expr>"
// Optimize "<var>+= -<expr>" to "<var>-= <expr>"
if ($assign->expression instanceof UnaryOpNode && '-' === $assign->expression->op && isset(self::$switch[$assign->op])) {
$assign = new AssignmentNode(['variable' => $assign->variable, 'expression' => $assign->expression->expression, 'op' => self::$switch[$assign->op]]);
}
// Not optimizable
return $assign;
}
/**
* Optimize a given node
*
* @param xp.compiler.ast.Node in
* @param xp.compiler.types.Scope scope
* @param xp.compiler.optimize.Optimizations optimizations
* @param xp.compiler.ast.Node optimized
*/
public function optimize(\xp\compiler\ast\Node $in, \xp\compiler\types\Scope $scope, Optimizations $optimizations)
{
if (!isset(self::$optimizable[$in->op])) {
return $in;
}
$in->lhs = $optimizations->optimize($this->unwrap($in->lhs), $scope);
$in->rhs = $optimizations->optimize($this->unwrap($in->rhs), $scope);
// Optimize "a + -b" to "a - b" and "a - -b" to "a + b"
if ($in->rhs instanceof UnaryOpNode && '-' === $in->rhs->op && isset(self::$switch[$in->op])) {
$in = new BinaryOpNode(['lhs' => $in->lhs, 'rhs' => $in->rhs->expression, 'op' => self::$switch[$in->op]]);
}
// Constant folding
if ($in->lhs instanceof Resolveable && $in->rhs instanceof Resolveable) {
$r = call_user_func_array([$this, 'eval' . self::$optimizable[$in->op]], [$in->lhs, $in->rhs]);
if (null !== $r) {
$in = $r;
}
}
return $in;
}