yetangitu/ghidra
1
0
Fork 0
mirror of https://github.com/NationalSecurityAgency/ghidra.git synced 2025-10-04 18:29:37 +02:00
Code Issues Releases Wiki Activity

More adjustments to boolean propagation

Browse source
This commit is contained in:
caheckman 2020-02-11 13:02:53 -05:00
parent 99367e1139
commit e6f09b141b
4 changed files with 33 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

2
Ghidra/Features/Decompiler/src/decompile/cpp/coreaction.cc
View file

@ -4393,7 +4393,7 @@ void PropagationState::step(void)
inslot = op->getSlot(vn);
return;
}
if (op == vn->getDef())
if (inslot == -1)
op = (PcodeOp *)0;
else
op = vn->getDef();

9
Ghidra/Features/Decompiler/src/decompile/cpp/subflow.cc
View file

@ -291,6 +291,15 @@ bool SubvariableFlow::tryReturnPull(PcodeOp *op,ReplaceVarnode *rvn,int4 slot)
return false;
if (inworklist)
worklist.push_back(rep);
else if (retvn->isConstant() && retop != op) {
// Trace won't revisit this RETURN, so we need to generate patch now
patchlist.push_back(PatchRecord());
patchlist.back().type = 2;
patchlist.back().pullop = retop;
patchlist.back().in1 = rep;
patchlist.back().slot = slot;
pullcount += 1;
}
}
returnsTraversed = true;
}

16
Ghidra/Features/Decompiler/src/decompile/cpp/type.hh
View file

@ -115,6 +115,7 @@ public:
virtual Datatype *clone(void) const=0; ///< Clone the data-type
virtual void saveXml(ostream &s) const; ///< Serialize the data-type to XML
int4 typeOrder(const Datatype &op) const { if (this==&op) return 0; return compare(op,10); } ///< Order this with -op- datatype
int4 typeOrderBool(const Datatype &op) const; ///< Order \b this with -op-, treating \e bool data-type as special
void saveXmlBasic(ostream &s) const; ///< Save basic data-type properties
void saveXmlRef(ostream &s) const; ///< Write an XML reference of \b this to stream
};
@ -447,4 +448,19 @@ public:
void cacheCoreTypes(void); ///< Cache common types
};
/// Order data-types, with special handling of the \e bool data-type. Data-types are compared
/// using the normal ordering, but \e bool is ordered after all other data-types. A return value
/// of 0 indicates the data-types are the same, -1 indicates that \b this is prefered (ordered earlier),
/// and 1 indicates \b this is ordered later.
/// \param op is the other data-type to compare with \b this
/// \return -1, 0, or 1
inline int4 Datatype::typeOrderBool(const Datatype &op) const
{
if (this == &op) return 0;
if (metatype == TYPE_BOOL) return 1; // Never prefer bool over other data-types
if (op.metatype == TYPE_BOOL) return -1;
return compare(op,10);
}
#endif

9
Ghidra/Features/Decompiler/src/decompile/cpp/variable.cc
View file

@ -112,7 +112,12 @@ void HighVariable::updateFlags(void) const
highflags &= ~flagsdirty; // Clear the dirty flag
}
/// Using Datatype::typeOrder, find the member Varnode with the most specific data-type.
/// Find the member Varnode with the most \e specialized data-type, handling \e bool specially.
/// Boolean data-types are \e specialized in the data-type lattice, but not all byte values are boolean values.
/// Within the Varnode/PcodeOp tree, the \e bool data-type can only propagate to a Varnode if it is verified to
/// only take the boolean values 0 and 1. Since the data-type representative represents the type of all
/// instances, if any instance is not boolean, then the HighVariable cannot be boolean, even though \e bool
/// is more specialized. This method uses Datatype::typeOrderBool() to implement the special handling.
/// \return the representative member
Varnode *HighVariable::getTypeRepresentative(void) const
@ -129,7 +134,7 @@ Varnode *HighVariable::getTypeRepresentative(void) const
if (vn->isTypeLock())
rep = vn;
}
else if (0>vn->getType()->typeOrder(*rep->getType()))
else if (0>vn->getType()->typeOrderBool(*rep->getType()))
rep = vn;
}
return rep;