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GP-4370 Internal Storage

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This commit is contained in:
caheckman 2024-04-19 16:54:30 +00:00
parent f1e2c8db04
commit 05818c5c3a
17 changed files with 219 additions and 63 deletions
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49
Ghidra/Features/Decompiler/src/decompile/cpp/varnode.cc
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@ -831,6 +831,55 @@ bool Varnode::isConstantExtended(uint8 *val) const
return false;
}
/// Recursively check if the Varnode is either:
/// - Copied or extended from a constant
/// - The result of arithmetic or logical operations on constants
/// - Loaded from a pointer that is a constant
///
/// \param maxBinary is the maximum depth of binary operations to inspect (before giving up)
/// \param maxLoad is the maximum number of CPUI_LOAD operations to allow in a sequence
/// \return \b true if the Varnode (might) collapse to a constant
bool Varnode::isEventualConstant(int4 maxBinary,int4 maxLoad) const
{
const Varnode *curVn = this;
while(!curVn->isConstant()) {
if (!curVn->isWritten()) return false;
const PcodeOp *op = curVn->getDef();
switch(op->code()) {
case CPUI_LOAD:
if (maxLoad == 0) return false;
maxLoad -= 1;
curVn = op->getIn(1);
break;
case CPUI_INT_ADD:
case CPUI_INT_SUB:
case CPUI_INT_XOR:
case CPUI_INT_OR:
case CPUI_INT_AND:
if (maxBinary == 0) return false;
if (!op->getIn(0)->isEventualConstant(maxBinary-1,maxLoad))
return false;
return op->getIn(1)->isEventualConstant(maxBinary-1,maxLoad);
case CPUI_INT_ZEXT:
case CPUI_INT_SEXT:
case CPUI_COPY:
curVn = op->getIn(0);
break;
case CPUI_INT_LEFT:
case CPUI_INT_RIGHT:
case CPUI_INT_SRIGHT:
case CPUI_INT_MULT:
if (!op->getIn(1)->isConstant()) return false;
curVn = op->getIn(0);
break;
default:
return false;
}
}
return true;
}
/// Make an initial determination of the Datatype of this Varnode. If a Datatype is already
/// set and locked return it. Otherwise look through all the read PcodeOps and the write PcodeOp
/// to determine if the Varnode is getting used as an \b int, \b float, or \b pointer, etc.