def lhs_ast(
self,
astree: AbstractSyntaxTree,
iaddr: str,
xdata: InstrXData) -> Tuple[ASTLval, List[ASTInstruction]]:
def indirect_lhs(
rtype: Optional[BCTyp]) -> Tuple[ASTLval, List[ASTInstruction]]:
tmplval = astree.mk_returnval_variable_lval(iaddr, rtype)
tmprhs = astree.mk_lval_expr(tmplval)
reglval = astree.mk_register_variable_lval("v0")
return (tmplval, [astree.mk_assign(reglval, tmprhs)])
calltarget = xdata.call_target(self.ixd)
tgtname = calltarget.name
models = ModelsAccess()
if astree.has_symbol(tgtname) and astree.symbol(tgtname).vtype:
fnsymbol = astree.symbol(tgtname)
if fnsymbol.returns_void:
return (astree.mk_ignored_lval(), [])
elif astree.ignore_return_value(tgtname):
return (astree.mk_ignored_lval(), [])
else:
return indirect_lhs(fnsymbol.vtype)
elif models.has_so_function_summary(tgtname):
summary = models.so_function_summary(tgtname)
returntype = summary.signature.returntype
if returntype.is_named_type:
returntype = cast(MNamedType, returntype)
typename = returntype.typename
if typename == "void" or typename == "VOID":
return (astree.mk_ignored_lval(), [])
elif astree.ignore_return_value(tgtname):
return (astree.mk_ignored_lval(), [])
else:
return indirect_lhs(None)
elif astree.ignore_return_value(tgtname):
return (astree.mk_ignored_lval(), [])
else:
return indirect_lhs(None)
else:
return indirect_lhs(None)
def annotation(self, xdata: InstrXData) -> str:
"""data format: a:<v0><args><call-target-ix> , or a:<v0>
xprs[0]: value of v0
xprs[1...]: arguments
xprs[-1]: index of call target in interface dictionary
"""
if xdata.has_call_target():
pargs = "(" + ", ".join(str(a)
for a in self.arguments(xdata)) + ")"
return str(xdata.call_target(self.ixd)) + pargs
else:
rhs = str(xdata.xprs[0])
if rhs.startswith("0x"):
syscallnumber = int(rhs, 16)
syscallfunction = SC.get_mips_linux_syscall(syscallnumber)
return "linux-systemcall:" + syscallfunction
else:
return "linux-systemcall(" + rhs + ")"
def annotation(self, xdata: InstrXData) -> str:
"""data format: a:xx... + c
direct call / resolved indirect call: xprs[0..] arguments
calltarget
unresolved indirect call: xprs[0] target expression
xprs[1] target expression (simplified)
xprs[2...] arguments
"""
if xdata.has_indirect_call_target_exprs():
tgtx = xdata.xprs[1]
callargs = xdata.xprs[2:]
return str(tgtx) + "(" + ",".join([str(x) for x in callargs]) + ")"
elif xdata.has_call_target():
ctgt = xdata.call_target(self.ixd)
callargs = xdata.xprs
return str(ctgt) + "(" + ",".join([str(x) for x in callargs]) + ")"
else:
return "call to " + str(self.tgtoperand)
def call_target(self, xdata: InstrXData) -> "CallTarget":
if self.is_call(xdata):
return xdata.call_target(self.ixd)
else:
raise UF.CHBError("Instruction is not a call: " + str(self))
def call_target(self, xdata: InstrXData) -> CallTarget:
return xdata.call_target(self.ixd)
def call_target(self, xdata: InstrXData) -> "CallTarget":
if xdata.has_call_target():
return xdata.call_target(self.ixd)
else:
raise UF.CHBError("Instruction does not have a call target: " +
str(self))
def call_target(self, xdata: InstrXData) -> "CallTarget":
if xdata.has_call_target():
return xdata.call_target(self.ixd)
else:
raise UF.CHBError("Call target not found for " + str(self))
