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GP-3873 Data-type alignment support in decompiler

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This commit is contained in:
caheckman 2023-09-22 16:08:18 +00:00
parent 6508088623
commit 64a58bdeab
29 changed files with 456 additions and 149 deletions
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33
Ghidra/Features/Decompiler/src/decompile/cpp/double.cc
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@ -3324,9 +3324,23 @@ int4 RuleDoubleLoad::applyOp(PcodeOp *op,Funcdata &data)
Varnode *piece1 = op->getIn(1);
if (!piece0->isWritten()) return 0;
if (!piece1->isWritten()) return 0;
if (piece0->getDef()->code() != CPUI_LOAD) return false;
if (piece1->getDef()->code() != CPUI_LOAD) return false;
if (!SplitVarnode::testContiguousPointers(piece0->getDef(),piece1->getDef(),loadlo,loadhi,spc))
PcodeOp *load1 = piece1->getDef();
if (load1->code() != CPUI_LOAD) return false;
PcodeOp *load0 = piece0->getDef();
OpCode opc = load0->code();
int4 offset = 0;
if (opc == CPUI_SUBPIECE) {
// Check for 2 LOADs but most significant part of most significant LOAD is discarded
if (load0->getIn(1)->getOffset() != 0) return false;
Varnode *vn0 = load0->getIn(0);
if (!vn0->isWritten()) return false;
offset = vn0->getSize() - piece0->getSize();
load0 = vn0->getDef();
opc = load0->code();
}
if (opc != CPUI_LOAD)
return false;
if (!SplitVarnode::testContiguousPointers(load0,load1,loadlo,loadhi,spc))
return 0;
size = piece0->getSize() + piece1->getSize();
@ -3340,8 +3354,17 @@ int4 RuleDoubleLoad::applyOp(PcodeOp *op,Funcdata &data)
data.opSetOpcode(newload,CPUI_LOAD);
data.opSetInput(newload,spcvn,0);
Varnode *addrvn = loadlo->getIn(1);
if (addrvn->isConstant())
addrvn = data.newConstant(addrvn->getSize(),addrvn->getOffset());
if (spc->isBigEndian() && offset != 0) {
// If the most significant part of LOAD is discarded, we need to add discard amount to pointer
PcodeOp *newadd = data.newOp(2,latest->getAddr());
Varnode *addout = data.newUniqueOut(addrvn->getSize(),newadd);
data.opSetOpcode(newadd,CPUI_INT_ADD);
data.opSetInput(newadd,addrvn,0);
data.opSetInput(newadd,data.newConstant(addrvn->getSize(), offset),1);
data.opInsertAfter(newadd,latest);
addrvn = addout;
latest = newadd;
}
data.opSetInput(newload,addrvn,1);
// We need to guarantee that -newload- reads -addrvn- after
// it has been defined. So insert it after the latest.