Source code for pyvex.lifting.util.syntax_wrapper

import functools
from typing import Union

from pyvex.const import get_type_size
from pyvex.expr import Const, IRExpr, RdTmp

from .vex_helper import IRSBCustomizer, Type

[docs]def checkparams(rhstype=None): def decorator(fn): @functools.wraps(fn) def inner_decorator(self, *args, **kwargs): irsb_cs = {a.irsb_c for a in list(args) + [self] if isinstance(a, VexValue)} # pylint: disable=no-member assert len(irsb_cs) == 1, "All VexValues must belong to the same irsb_c" args = list(args) for idx, arg in enumerate(args): if isinstance(arg, int): thetype = rhstype if rhstype else self.ty args[idx] = VexValue.Constant(self.irsb_c, arg, thetype) elif not isinstance(arg, VexValue): raise Exception("Cannot convert param %s" % str(arg)) args = tuple(args) return fn(self, *args, **kwargs) return inner_decorator return decorator
[docs]def vvifyresults(f): @functools.wraps(f) def decor(self, *args, **kwargs): returned = f(self, *args, **kwargs) assert isinstance(returned, RdTmp) or isinstance(returned, Const) return VexValue(self.irsb_c, returned) return decor
[docs]class VexValue:
[docs] def __init__(self, irsb_c: "IRSBCustomizer", rdt: "Union[RdTmp, Const]", signed=False): self.irsb_c = irsb_c self.ty = self.irsb_c.get_type(rdt) self.rdt = rdt self.width = get_type_size(self.ty) self._is_signed = signed
@property def value(self): if isinstance(self.rdt, Const): return self.rdt.con.value else: raise ValueError("Non-constant VexValue has no value property") @property def signed(self): return VexValue(self.irsb_c, self.rdt, True)
[docs] @vvifyresults def widen_unsigned(self, ty): return self.irsb_c.op_widen_int_unsigned(self.rdt, ty)
[docs] @vvifyresults def cast_to(self, ty, signed=False, high=False): return self.irsb_c.cast_to(self.rdt, ty, signed=signed, high=high)
[docs] @vvifyresults def widen_signed(self, ty): return self.irsb_c.op_widen_int_signed(self.rdt, ty)
[docs] @vvifyresults def narrow_high(self, ty): return self.irsb_c.op_narrow_int(self.rdt, ty, high_half=True)
[docs] @vvifyresults def narrow_low(self, ty): return self.irsb_c.op_narrow_int(self.rdt, ty, high_half=False)
# TODO at some point extend this to Vex nonconstants def __getitem__(self, idx): def getb(i): return VexValue(self.irsb_c, self.irsb_c.get_bit(self.rdt, i)) def makeconstant(x): return VexValue.Constant(self.irsb_c, x, Type.int_8).rdt if not isinstance(idx, slice): actualindex = slice(idx).indices(self.width)[1] return getb(makeconstant(actualindex)) else: return [getb(makeconstant(i)) for i in range(*idx.indices(self.width))] def __setitem__(self, idx, bval): setted = self.set_bit(idx, bval) self.__init__(setted.irsb_c, setted.rdt)
[docs] @checkparams() @vvifyresults def set_bit(self, idx, bval): return self.irsb_c.set_bit(self.rdt, idx.rdt, bval.rdt)
[docs] @checkparams() @vvifyresults def set_bits(self, idxsandvals): return self.irsb_c.set_bits(self.rdt, [(i.cast_to(Type.int_8).rdt, b.rdt) for i, b in idxsandvals])
[docs] @checkparams() @vvifyresults def ite(self, iftrue, iffalse): onebitcond = self.cast_to(Type.int_1) return self.irsb_c.ite(onebitcond.rdt, iftrue.rdt, iffalse.rdt)
[docs] @checkparams() @vvifyresults def sar(self, right): """ `v.sar(r)` should do arithmetic shift right of `v` by `r` :param right:VexValue value to shift by :return: VexValue - result of a shift """ return self.irsb_c.op_sar(self.rdt, right.rdt)
@checkparams() @vvifyresults def __add__(self, right): return self.irsb_c.op_add(self.rdt, right.rdt) @checkparams() def __radd__(self, left): return self + left @checkparams() @vvifyresults def __sub__(self, right): return self.irsb_c.op_sub(self.rdt, right.rdt) @checkparams() def __rsub__(self, left): return left - self @checkparams() @vvifyresults def __div__(self, right): if self._is_signed: return self.irsb_c.op_sdiv(self.rdt, right.rdt) else: return self.irsb_c.op_udiv(self.rdt, right.rdt) @checkparams() def __rdiv__(self, left): return left // self @checkparams() def __floordiv__(self, right): # Note: nonprimitive return self.__div__(right) @checkparams() def __rfloordiv__(self, left): return left // self @checkparams() def __truediv__(self, right): # Note: nonprimitive return self / right @checkparams() def __rtruediv__(self, left): return left.__truediv__(self) @checkparams() @vvifyresults def __and__(self, right): return self.irsb_c.op_and(self.rdt, right.rdt) @checkparams() def __rand__(self, left): return left & self @checkparams() @vvifyresults def __eq__(self, right): return self.irsb_c.op_cmp_eq(self.rdt, right.rdt) @checkparams() @vvifyresults def __ne__(self, other): return self.irsb_c.op_cmp_ne(self.rdt, other.rdt) @checkparams() @vvifyresults def __invert__(self): return self.irsb_c.op_not(self.rdt) @checkparams() @vvifyresults def __le__(self, right): if self._is_signed: return self.irsb_c.op_cmp_sle(self.rdt, right.rdt) else: return self.irsb_c.op_cmp_ule(self.rdt, right.rdt) @checkparams() @vvifyresults def __gt__(self, other): if self._is_signed: return self.irsb_c.op_cmp_sgt(self.rdt, other.rdt) else: return self.irsb_c.op_cmp_ugt(self.rdt, other.rdt) @checkparams() @vvifyresults def __ge__(self, right): if self._is_signed: return self.irsb_c.op_cmp_sge(self.rdt, right.rdt) else: return self.irsb_c.op_cmp_uge(self.rdt, right.rdt) @checkparams(rhstype=Type.int_8) @vvifyresults def __lshift__(self, right): # TODO put better type inference in irsb_c so we can have rlshift """ logical shift left """ return self.irsb_c.op_shl(self.rdt, right.rdt) @checkparams() @vvifyresults def __lt__(self, right): if self._is_signed: return self.irsb_c.op_cmp_slt(self.rdt, right.rdt) else: return self.irsb_c.op_cmp_ult(self.rdt, right.rdt) @checkparams() @vvifyresults def __mod__(self, right): # Note: nonprimitive return self.irsb_c.op_mod(self.rdt, right.rdt) @checkparams() def __rmod__(self, left): return left % self @checkparams() @vvifyresults def __mul__(self, right): if self._is_signed: return self.irsb_c.op_smul(self.rdt, right.rdt) else: return self.irsb_c.op_umul(self.rdt, right.rdt) @checkparams() def __rmul__(self, left): return left * self @checkparams() @vvifyresults def __neg__(self): # Note: nonprimitive if not self._is_signed: raise Exception("Number is unsigned, cannot change sign!") else: return self.rdt * -1 @checkparams() @vvifyresults def __or__(self, right): return self.irsb_c.op_or(self.rdt, right.rdt) def __ror__(self, left): return self | left @checkparams() @vvifyresults def __pos__(self): return self @checkparams(rhstype=Type.int_8) @vvifyresults def __rshift__(self, right): """ logical shift right """ return self.irsb_c.op_shr(self.rdt, right.rdt) @checkparams() def __rlshift__(self, left): return left << self @checkparams() def __rrshift__(self, left): return left >> self @checkparams() @vvifyresults def __xor__(self, right): return self.irsb_c.op_xor(self.rdt, right.rdt) def __rxor__(self, left): return self ^ left
[docs] @classmethod def Constant(cls, irsb_c, val, ty): """ Creates a constant as a VexValue :param irsb_c: The IRSBCustomizer to use :param val: The value, as an integer :param ty: The type of the resulting VexValue :return: a VexValue """ assert not (isinstance(val, VexValue) or isinstance(val, IRExpr)) rdt = irsb_c.mkconst(val, ty) return cls(irsb_c, rdt)