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hsail: fix unsigned offset bug in address calculation

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it's possible for the offset provided to an HSAIL mem inst to be a negative
value, however the variable we use to hold the offset is an unsigned type.
this can lead to excessively large offset values when the offset is negative,
which will almost certainly cause the access to go out of bounds.
This commit is contained in:
Tony Gutierrez 2016-12-02 11:40:52 -05:00
parent 80607a2a1d
commit 38708f369b
1 changed files with 12 additions and 2 deletions
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14
src/arch/hsail/operand.hh
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@ -591,7 +591,7 @@ class AddrOperandBase : public BaseOperand
virtual void calcVector(Wavefront *w, std::vector<Addr> &addrVec) = 0;
virtual uint64_t calcLane(Wavefront *w, int lane=0) = 0;
uint64_t offset;
int64_t offset;
const char *name = nullptr;
StorageElement *storageElement;
};
@ -627,14 +627,24 @@ RegAddrOperand<RegOperandType>::init(unsigned opOffset, const BrigObject *obj)
const BrigOperandAddress *op = (BrigOperandAddress*)baseOp;
storageElement = nullptr;
offset = (uint64_t(op->offset.hi) << 32) | uint64_t(op->offset.lo);
reg.init(op->reg, obj);
if (reg.regFileChar == 's') {
// if the address expression is 32b, then the hi
// bits of the offset must be set to 0 in the BRIG
assert(!op->offset.hi);
/**
* the offset field of an HSAIL instruction may be negative
* so here we cast the raw bits we get from the BRIG file to
* a signed type to avoid address calculation errors
*/
offset = (int32_t)(op->offset.lo);
reg.regOperandSize = sizeof(uint32_t);
registerType = Enums::RT_VECTOR;
}
else if (reg.regFileChar == 'd') {
offset = (int64_t)(((uint64_t)(op->offset.hi) << 32)
| (uint64_t)(op->offset.lo));
reg.regOperandSize = sizeof(uint64_t);
registerType = Enums::RT_VECTOR;
}