def transform_unary_minus_expr(self,
unary_minus: ir.UnaryMinusExpr) -> ir.Expr:
expr = self.transform_expr(unary_minus.inner_expr)
# -(3) => -3
if isinstance(expr, ir.Literal):
assert isinstance(expr.value, int)
return ir.Literal(-expr.value)
# -(x - y) => y - x
if isinstance(expr, ir.Int64BinaryOpExpr) and expr.op == '-':
return ir.Int64BinaryOpExpr(lhs=expr.rhs, rhs=expr.lhs, op='-')
return ir.UnaryMinusExpr(expr)
def transform_comparison_expr(self,
comparison: ir.ComparisonExpr) -> ir.Expr:
lhs = comparison.lhs
rhs = comparison.rhs
op = comparison.op
lhs = self.transform_expr(lhs)
rhs = self.transform_expr(rhs)
if isinstance(lhs, ir.Literal) and isinstance(rhs, ir.Literal):
if op == '==':
return ir.Literal(lhs.value == rhs.value)
if op == '!=':
return ir.Literal(lhs.value != rhs.value)
if op == '<':
return ir.Literal(lhs.value < rhs.value)
if op == '<=':
return ir.Literal(lhs.value <= rhs.value)
if op == '>':
return ir.Literal(lhs.value > rhs.value)
if op == '>=':
return ir.Literal(lhs.value >= rhs.value)
if op in ('==', '!=') and self._is_syntactically_equal(
lhs, rhs) and not expr_can_trigger_static_asserts(lhs):
if self._can_remove_subexpression(
lhs) and self._can_remove_subexpression(rhs):
return {
'==': ir.Literal(True),
'!=': ir.Literal(False),
}[op]
if op in ('==', '!=') and isinstance(
rhs, ir.Literal) and rhs.expr_type == ir.BoolType():
rhs, lhs = lhs, rhs
if op in ('==', '!=') and isinstance(
lhs, ir.Literal) and lhs.expr_type == ir.BoolType():
return {
('==', True): lambda: rhs,
('==', False): lambda: self.transform_expr(ir.NotExpr(rhs)),
('!=', True): lambda: self.transform_expr(ir.NotExpr(rhs)),
('!=', False): lambda: rhs,
}[(op, lhs.value)]()
return ir.ComparisonExpr(lhs, rhs, op)
def transform_bool_binary_op_expr(
self, binary_op: ir.BoolBinaryOpExpr) -> ir.Expr:
lhs = binary_op.lhs
rhs = binary_op.rhs
op = binary_op.op
lhs = self.transform_expr(lhs)
rhs = self.transform_expr(rhs)
if op == '&&':
# true && false => false
if isinstance(lhs, ir.Literal) and isinstance(rhs, ir.Literal):
return ir.Literal(lhs.value and rhs.value)
# true && x => x
if isinstance(lhs, ir.Literal) and lhs.value is True:
return rhs
# x && true => x
if isinstance(rhs, ir.Literal) and rhs.value is True:
return lhs
# false && x => false
if isinstance(lhs, ir.Literal) and lhs.value is False:
if self._can_remove_subexpression(rhs):
return ir.Literal(False)
# x && false => false
if isinstance(rhs, ir.Literal) and rhs.value is False:
if self._can_remove_subexpression(lhs):
return ir.Literal(False)
if op == '||':
# true || false => true
if isinstance(lhs, ir.Literal) and isinstance(rhs, ir.Literal):
return ir.Literal(lhs.value or rhs.value)
# false || x => x
if isinstance(lhs, ir.Literal) and lhs.value is False:
return rhs
# x || false => x
if isinstance(rhs, ir.Literal) and rhs.value is False:
return lhs
# true || x => true
if isinstance(lhs, ir.Literal) and lhs.value is True:
if self._can_remove_subexpression(rhs):
return ir.Literal(True)
# x || true => true
if isinstance(rhs, ir.Literal) and rhs.value is True:
if self._can_remove_subexpression(lhs):
return ir.Literal(True)
return ir.BoolBinaryOpExpr(lhs, rhs, op)
def transform_not_expr(self, not_expr: ir.NotExpr) -> ir.Expr:
expr = self.transform_expr(not_expr.inner_expr)
# !true => false
# !false => true
if isinstance(expr, ir.Literal):
assert isinstance(expr.value, bool)
return ir.Literal(not expr.value)
# !!x => x
if isinstance(expr, ir.NotExpr):
return expr.inner_expr
# !(x && y) => (!x || !y)
# !(x || y) => (!x && !y)
if isinstance(expr, ir.BoolBinaryOpExpr):
op = {
'&&': '||',
'||': '&&',
}[expr.op]
return self.transform_expr(
ir.BoolBinaryOpExpr(lhs=ir.NotExpr(expr.lhs),
rhs=ir.NotExpr(expr.rhs),
op=op))
# !(x == y) => x != y
# !(x != y) => x == y
# !(x < y) => x >= y
# !(x <= y) => x > y
# !(x > y) => x <= y
# !(x >= y) => x < y
if isinstance(expr, ir.ComparisonExpr) and expr.op in ('==', '!='):
op = {
'==': '!=',
'!=': '==',
'<': '>=',
'<=': '>',
'>': '<=',
'>=': '<',
}[expr.op]
return ir.ComparisonExpr(expr.lhs, expr.rhs, op)
return ir.NotExpr(expr)
def transform_int64_binary_op_expr(
self, binary_op: ir.Int64BinaryOpExpr) -> ir.Expr:
lhs = binary_op.lhs
rhs = binary_op.rhs
op = binary_op.op
# (x - y) => (x + -y)
# This pushes down the minus, so that e.g. (x - (-y)) => (x + y).
if op == '-':
rhs = ir.UnaryMinusExpr(rhs)
op = '+'
lhs = self.transform_expr(lhs)
rhs = self.transform_expr(rhs)
if op == '+' and isinstance(rhs, ir.UnaryMinusExpr):
# We could not push down the minus, so switch back to a subtraction.
op = '-'
rhs = rhs.inner_expr
if op == '+':
# 3 + 5 => 8
if isinstance(lhs, ir.Literal) and isinstance(rhs, ir.Literal):
return ir.Literal(lhs.value + rhs.value)
# 0 + x => x
if isinstance(lhs, ir.Literal) and lhs.value == 0:
return rhs
# x + 0 => x
if isinstance(rhs, ir.Literal) and rhs.value == 0:
return lhs
if op == '-':
# 8 - 5 => 3
if isinstance(lhs, ir.Literal) and isinstance(rhs, ir.Literal):
return ir.Literal(lhs.value - rhs.value)
# 0 - x => -x
if isinstance(lhs, ir.Literal) and lhs.value == 0:
return ir.UnaryMinusExpr(rhs)
# x - 0 => x
if isinstance(rhs, ir.Literal) and rhs.value == 0:
return lhs
if op == '*':
# 3 * 5 => 15
if isinstance(lhs, ir.Literal) and isinstance(rhs, ir.Literal):
return ir.Literal(lhs.value * rhs.value)
# 0 * x => 0
if isinstance(lhs, ir.Literal) and lhs.value == 0:
if self._can_remove_subexpression(rhs):
return ir.Literal(0)
# x * 0 => 0
if isinstance(rhs, ir.Literal) and rhs.value == 0:
if self._can_remove_subexpression(lhs):
return ir.Literal(0)
# 1 * x => x
if isinstance(lhs, ir.Literal) and lhs.value == 1:
return rhs
# x * 1 => x
if isinstance(rhs, ir.Literal) and rhs.value == 1:
return lhs
if op == '/':
# 16 / 3 => 5
if isinstance(lhs, ir.Literal) and isinstance(rhs, ir.Literal):
return ir.Literal(lhs.value // rhs.value)
# x / 1 => x
if isinstance(rhs, ir.Literal) and rhs.value == 1:
return lhs
if op == '%':
# 16 % 3 => 1
if isinstance(lhs, ir.Literal) and isinstance(rhs, ir.Literal):
return ir.Literal(lhs.value % rhs.value)
# x % 1 => 0
if isinstance(rhs, ir.Literal) and rhs.value == 1:
return ir.Literal(0)
return ir.Int64BinaryOpExpr(lhs, rhs, op)
result_element_names=['value'],
args=[
ir.TemplateArgDecl(
name='T', expr_type=ir.TypeType(), is_variadic=False),
ir.TemplateArgDecl(
name='U', expr_type=ir.TypeType(), is_variadic=False)
],
main_definition=ir.TemplateSpecialization(
args=[
ir.TemplateArgDecl(
name='T', expr_type=ir.TypeType(), is_variadic=False),
ir.TemplateArgDecl(
name='U', expr_type=ir.TypeType(), is_variadic=False)
],
patterns=None,
body=[ir.ConstantDef(name='value', expr=ir.Literal(False))],
is_metafunction=True),
specializations=[
ir.TemplateSpecialization(
args=[
ir.TemplateArgDecl(
name='T', expr_type=ir.TypeType(), is_variadic=False)
],
patterns=[
ir.AtomicTypeLiteral.for_local(cpp_type='T',
expr_type=ir.TypeType(),
is_variadic=False),
ir.AtomicTypeLiteral.for_local(cpp_type='T',
expr_type=ir.TypeType(),
is_variadic=False)
],