import logging
from ailment import Expr
from .engine_base import SimplifierAILEngine, SimplifierAILState
from .optimization_pass import OptimizationPass, OptimizationPassStage
_l = logging.getLogger(name=__name__)
[docs]class MultiSimplifierAILEngine(SimplifierAILEngine):
"""
An AIL pass for the multi simplifier
"""
def _ail_handle_Add(self, expr):
operand_0 = self._expr(expr.operands[0])
operand_1 = self._expr(expr.operands[1])
# x + x = 2*x
if type(operand_0) in [Expr.Convert, Expr.Register]:
if isinstance(operand_1, (Expr.Convert, Expr.Register)):
if operand_0 == operand_1:
count = Expr.Const(expr.idx, None, 2, 8)
return Expr.BinaryOp(expr.idx, "Mul", [operand_1, count], expr.signed, **expr.tags)
# 2*x + x = 3*x
if Expr.BinaryOp in [type(operand_0), type(operand_1)]:
if (
isinstance(operand_1, Expr.BinaryOp)
and operand_1.op == "Mul"
and (
not isinstance(operand_0, Expr.BinaryOp)
or (isinstance(operand_0, Expr.BinaryOp) and operand_0.op != "Mul")
)
):
x0 = operand_0
x1_index = 0 if isinstance(operand_1.operands[1], Expr.Const) else 1
x1 = operand_1.operands[x1_index]
const_x1 = operand_1.operands[1 - x1_index]
if x0 == x1:
new_const = Expr.Const(const_x1.idx, None, const_x1.value + 1, const_x1.bits)
new_expr = Expr.BinaryOp(expr.idx, "Mul", [x0, new_const], expr.signed, **expr.tags)
return new_expr
elif (
isinstance(operand_0, Expr.BinaryOp)
and operand_0.op == "Mul"
and (
not isinstance(operand_1, Expr.BinaryOp)
or (isinstance(operand_1, Expr.BinaryOp) and operand_1.op != "Mul")
)
):
x1 = operand_1
x0_index = 0 if isinstance(operand_0.operands[1], Expr.Const) else 1
x0 = operand_0.operands[x0_index]
const_x0 = operand_0.operands[1 - x0_index]
if x0 == x1:
new_const = Expr.Const(const_x0.idx, None, const_x0.value + 1, const_x0.bits)
new_expr = Expr.BinaryOp(expr.idx, "Mul", [x1, new_const], expr.signed, **expr.tags)
return new_expr
# 2*x + 3*x = 5*x
elif (
isinstance(operand_0, Expr.BinaryOp)
and isinstance(operand_1, Expr.BinaryOp)
and operand_0.op == "Mul"
and operand_1.op == "Mul"
):
if Expr.Const in [type(operand_0.operands[0]), type(operand_0.operands[1])] and Expr.Const in [
type(operand_1.operands[0]),
type(operand_1.operands[1]),
]:
x0_index = 0 if isinstance(operand_0.operands[1], Expr.Const) else 1
x0 = operand_0.operands[x0_index]
const_x0 = operand_0.operands[1 - x0_index]
x1_index = 0 if isinstance(operand_1.operands[1], Expr.Const) else 1
x1 = operand_1.operands[x1_index]
const_x1 = operand_1.operands[1 - x1_index]
if x0 == x1:
new_const = Expr.Const(const_x1.idx, None, const_x1.value + const_x0.value, const_x1.bits)
new_expr = Expr.BinaryOp(expr.idx, "Mul", [x0, new_const], expr.signed, **expr.tags)
return new_expr
if (operand_0, operand_1) != (expr.operands[0], expr.operands[1]):
return Expr.BinaryOp(expr.idx, "Add", [operand_0, operand_1], expr.signed, **expr.tags)
return expr
def _ail_handle_Sub(self, expr):
operand_0 = self._expr(expr.operands[0])
operand_1 = self._expr(expr.operands[1])
# x + x = 2*x
if type(operand_0) in [Expr.Convert, Expr.Register]:
if isinstance(operand_1, (Expr.Convert, Expr.Register)):
if operand_0 == operand_1:
count = Expr.Const(expr.idx, None, 0, 8)
new_expr = Expr.BinaryOp(expr.idx, "Mul", [operand_1, count], expr.signed, **expr.tags)
return new_expr
# 2*x - x = x
if Expr.BinaryOp in [type(operand_0), type(operand_1)]:
if (
isinstance(operand_1, Expr.BinaryOp)
and operand_1.op == "Mul"
and (
not isinstance(operand_0, Expr.BinaryOp)
or (isinstance(operand_0, Expr.BinaryOp) and operand_0.op != "Mul")
)
):
x0 = operand_0
x1_index = 0 if isinstance(operand_1.operands[1], Expr.Const) else 1
x1 = operand_1.operands[x1_index]
const_x1 = operand_1.operands[1 - x1_index]
if x0 == x1:
new_const = Expr.Const(const_x1.idx, None, const_x1.value - 1, const_x1.bits)
new_expr = Expr.BinaryOp(expr.idx, "Mul", [x0, new_const], expr.signed, **expr.tags)
return new_expr
elif (
isinstance(operand_0, Expr.BinaryOp)
and operand_0.op == "Mul"
and (
not isinstance(operand_1, Expr.BinaryOp)
or (isinstance(operand_1, Expr.BinaryOp) and operand_1.op != "Mul")
)
):
x1 = operand_1
x0_index = 0 if isinstance(operand_0.operands[1], Expr.Const) else 1
x0 = operand_0.operands[x0_index]
const_x0 = operand_0.operands[1 - x0_index]
if x0 == x1:
new_const = Expr.Const(const_x0.idx, None, const_x0.value - 1, const_x0.bits)
new_expr = Expr.BinaryOp(expr.idx, "Mul", [x1, new_const], expr.signed, **expr.tags)
return new_expr
# 3*x - 2*x = x
elif (
isinstance(operand_0, Expr.BinaryOp)
and isinstance(operand_1, Expr.BinaryOp)
and operand_0.op == "Mul"
and operand_1.op == "Mul"
):
if Expr.Const in [type(operand_0.operands[0]), type(operand_0.operands[1])] and Expr.Const in [
type(operand_1.operands[0]),
type(operand_1.operands[1]),
]:
x0_index = 0 if isinstance(operand_0.operands[1], Expr.Const) else 1
x0 = operand_0.operands[x0_index]
const_x0 = operand_0.operands[1 - x0_index]
x1_index = 0 if isinstance(operand_1.operands[1], Expr.Const) else 1
x1 = operand_1.operands[x1_index]
const_x1 = operand_1.operands[1 - x1_index]
if x0 == x1:
new_const = Expr.Const(const_x1.idx, None, const_x0.value - const_x1.value, const_x1.bits)
new_expr = Expr.BinaryOp(expr.idx, "Mul", [x0, new_const], expr.signed, **expr.tags)
return new_expr
if (operand_0, operand_1) != (expr.operands[0], expr.operands[1]):
return Expr.BinaryOp(expr.idx, "Sub", [operand_0, operand_1], expr.signed, **expr.tags)
return expr
def _ail_handle_Shl(self, expr):
operand_0 = self._expr(expr.operands[0])
operand_1 = self._expr(expr.operands[1])
if isinstance(operand_1, Expr.Const):
new_operand = Expr.Const(operand_1.idx, None, 2**operand_1.value, operand_0.bits)
return Expr.BinaryOp(expr.idx, "Mul", [operand_0, new_operand], expr.signed, **expr.tags)
if (operand_0, operand_1) != (expr.operands[0], expr.operands[1]):
return Expr.BinaryOp(expr.idx, "Shl", [operand_0, operand_1], expr.signed, **expr.tags)
return expr
def _ail_handle_Mul(self, expr):
operand_0 = self._expr(expr.operands[0])
operand_1 = self._expr(expr.operands[1])
if Expr.Const in [type(operand_0), type(operand_1)]:
if Expr.BinaryOp in [type(operand_0), type(operand_1)]:
const_, x0 = (operand_0, operand_1) if isinstance(operand_0, Expr.Const) else (operand_1, operand_0)
if x0.op == "Mul" and Expr.Const in [type(x0.operands[0]), type(x0.operands[1])]:
if isinstance(x0.operands[0], Expr.Const):
const_x0, x = x0.operands[0], x0.operands[1]
else:
const_x0, x = x0.operands[1], x0.operands[0]
new_const = Expr.Const(const_.idx, None, const_.value * const_x0.value, const_.bits)
new_expr = Expr.BinaryOp(expr.idx, "Mul", [x, new_const], expr.signed, **expr.tags)
return new_expr
elif (
isinstance(operand_0, Expr.Convert)
and isinstance(operand_0.operand, Expr.BinaryOp)
and operand_0.operand.op == "Mul"
and isinstance(operand_0.operand.operands[1], Expr.Const)
):
x = operand_0.operand.operands[0]
new_const = Expr.Const(
operand_1.idx, None, operand_1.value * operand_0.operand.operands[1].value, operand_1.bits
)
new_expr = Expr.BinaryOp(expr.idx, "Mul", [x, new_const], expr.signed, **expr.tags)
return new_expr
if (operand_0, operand_1) != (expr.operands[0], expr.operands[1]):
return Expr.BinaryOp(expr.idx, "Mul", [operand_0, operand_1], expr.signed, **expr.tags)
return expr
[docs]class MultiSimplifier(OptimizationPass):
"""
Implements several different arithmetic optimizations.
"""
ARCHES = ["X86", "AMD64"]
PLATFORMS = ["linux", "windows"]
STAGE = OptimizationPassStage.AFTER_GLOBAL_SIMPLIFICATION
NAME = "Simplify various arithmetic expressions"
DESCRIPTION = __doc__.strip()
[docs] def __init__(self, func, **kwargs):
super().__init__(func, **kwargs)
self.state = SimplifierAILState(self.project.arch)
self.engine = MultiSimplifierAILEngine()
self.analyze()
def _check(self):
return True, None
def _analyze(self, cache=None):
for block in list(self._graph.nodes()):
new_block = block
old_block = None
while new_block != old_block:
old_block = new_block
new_block = self.engine.process(state=self.state.copy(), block=old_block.copy())
_l.debug("new block: %s", new_block.statements)
self._update_block(block, new_block)