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Merged
jakobbotsch merged 17 commits into from
May 6, 2022
Merged

Physical value numbering #68712

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90cb15f
Work around FIELD turning into IND(struct)
SingleAccretion Apr 29, 2022
2f7141a
Delete "ROH"
SingleAccretion Apr 20, 2022
4d45ecc
Physical VN -- locals
SingleAccretion Apr 18, 2022
9a59a6f
Physical VN -- fields
SingleAccretion Apr 19, 2022
e8758c6
Physical VN -- arrays
SingleAccretion Apr 20, 2022
670a5cd
Deleting VNApplySelectors[Assign]
SingleAccretion Apr 20, 2022
b1950c9
Delete VNForEmptyMap
SingleAccretion Apr 25, 2022
10e1807
Add function headers
SingleAccretion Apr 20, 2022
f97c1ad
fgValueNumberLocalStore: fix arg ordering
SingleAccretion Apr 25, 2022
caa1998
Add BitCast<type <- ZeroObj> folding
SingleAccretion Apr 29, 2022
221fe64
Fix block assignment numbering
SingleAccretion Apr 29, 2022
fc03ae6
Add more TODO-PhysicalVN notes
SingleAccretion Apr 30, 2022
535b406
Update the documentation on maps and selection
SingleAccretion Apr 30, 2022
64b3cf6
Use a 'switch' in VNForMapSelectWork
SingleAccretion May 1, 2022
0c6af71
Fix formatting
SingleAccretion Apr 30, 2022
d1d5aea
Fix the CAST<float <-> integer> bug
SingleAccretion May 1, 2022
051224d
Correct documentation mistakes
SingleAccretion May 5, 2022
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Fix block assignment numbering
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@SingleAccretion
SingleAccretion committed May 2, 2022
commit 221fe64528184ffced0794424c689fecfc54878f
79 changes: 29 additions & 50 deletions src/coreclr/jit/valuenum.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -4564,7 +4564,7 @@ void Compiler::fgValueNumberLocalStore(GenTree* storeNode,
ValueNumPair newLclValue;
if (vnStore->LoadStoreIsEntire(lclSize, offset, storeSize))
{
newLclValue = normalize ? vnStore->VNPairForLoadStoreBitCast(value, varDsc->TypeGet(), lclSize) : value;
newLclValue = value;
}
else
{
Expand All @@ -4578,8 +4578,12 @@ void Compiler::fgValueNumberLocalStore(GenTree* storeNode,
// Any out-of-bounds stores should have made the local address-exposed.
assert(newLclValue.BothDefined());

// We normalize types stored in local locations because things outside VN itself look at them.
assert((genActualType(vnStore->TypeOfVN(newLclValue.GetLiberal())) == genActualType(varDsc)) || !normalize);
if (normalize)
{
// We normalize types stored in local locations because things outside VN itself look at them.
newLclValue = vnStore->VNPairForLoadStoreBitCast(newLclValue, varDsc->TypeGet(), lclSize);
assert((genActualType(vnStore->TypeOfVN(newLclValue.GetLiberal())) == genActualType(varDsc)));
}

varDsc->GetPerSsaData(lclDefSsaNum)->m_vnPair = newLclValue;

Expand Down Expand Up @@ -8238,77 +8242,52 @@ void Compiler::fgValueNumberBlockAssignment(GenTree* tree)
lhsFldSeq = vnStore->FieldSeqVNToFieldSeq(lhsAddrFunc.m_args[1]);
}

bool isNewUniq = false;
ValueNumPair newLhsLclVNPair = ValueNumPair();
ValueNumPair rhsVNPair = ValueNumPair();
if (tree->OperIsInitBlkOp())
{
ValueNum lclVarVN = ValueNumStore::NoVN;
ValueNum initObjVN = ValueNumStore::NoVN;
if (isEntire && rhs->IsIntegralConst(0))
{
// Note that it is possible to see pretty much any kind of type for the local
// (not just TYP_STRUCT) here because of the ASG(BLK(ADDR(LCL_VAR/FLD)), 0) form.
lclVarVN = (lhsVarDsc->TypeGet() == TYP_STRUCT) ? vnStore->VNForZeroObj(lhsVarDsc->GetStructHnd())
: vnStore->VNZeroForType(lhsVarDsc->TypeGet());
initObjVN = (lhsVarDsc->TypeGet() == TYP_STRUCT) ? vnStore->VNForZeroObj(lhsVarDsc->GetStructHnd())
: vnStore->VNZeroForType(lhsVarDsc->TypeGet());
}
else
{
// Non-zero block init is very rare so we'll use a simple, unique VN here.
lclVarVN = vnStore->VNForExpr(compCurBB, lhsVarDsc->TypeGet());
isNewUniq = true;
initObjVN = vnStore->VNForExpr(compCurBB, lhsVarDsc->TypeGet());

// TODO-PhysicalVN: remove this pessimization, it was added to avoid diffs.
// There is no need to invalidate the whole local.
offset = 0;
storeSize = lhsLclSize;
}

newLhsLclVNPair.SetBoth(lclVarVN);
rhsVNPair.SetBoth(initObjVN);
}
else
{
assert(tree->OperIsCopyBlkOp());

rhsVNPair = vnStore->VNPNormalPair(rhs->gtVNPair);

// TODO-PhysicalVN: with the physical VN scheme, we no longer need this check.
if (fgValueNumberBlockAssignmentTypeCheck(lhsVarDsc, lhsFldSeq, rhs))
if (!fgValueNumberBlockAssignmentTypeCheck(lhsVarDsc, lhsFldSeq, rhs))
{
ValueNumPair rhsVNPair = vnStore->VNPNormalPair(rhs->gtVNPair);

// TODO-PhysicalVN: remove this quirk, it was added to avoid diffs.
if (lhs->TypeIs(TYP_STRUCT) && (vnStore->TypeOfVN(rhsVNPair.GetLiberal()) != TYP_STRUCT))
{
rhsVNPair.SetBoth(vnStore->VNForExpr(compCurBB, TYP_STRUCT));
}

if (isEntire)
{
newLhsLclVNPair = vnStore->VNPairForLoadStoreBitCast(rhsVNPair, lhsVarDsc->TypeGet(),
lhsLclSize);
}
else
{
ValueNumPair oldLhsLclVNPair = lhsVarDsc->GetPerSsaData(lclVarTree->GetSsaNum())->m_vnPair;
newLhsLclVNPair = vnStore->VNPairForStore(oldLhsLclVNPair, lhsLclSize, offset,
storeSize, rhsVNPair);
}
// Invalidate the whole local.
rhsVNPair.SetBoth(vnStore->VNForExpr(compCurBB, lhsVarDsc->TypeGet()));
offset = 0;
storeSize = lhsLclSize;
}
else
// TODO-PhysicalVN: remove this quirk, it was added to avoid diffs.
else if (lhs->TypeIs(TYP_STRUCT) && (vnStore->TypeOfVN(rhsVNPair.GetLiberal()) != TYP_STRUCT))
{
newLhsLclVNPair.SetBoth(vnStore->VNForExpr(compCurBB, lhsVarDsc->TypeGet()));
isNewUniq = true;
rhsVNPair.SetBoth(vnStore->VNForExpr(compCurBB, lhsVarDsc->TypeGet()));
}
}

lhsVarDsc->GetPerSsaData(lclDefSsaNum)->m_vnPair = newLhsLclVNPair;

#ifdef DEBUG
if (verbose)
{
printf("Tree ");
Compiler::printTreeID(tree);
printf(" assigned VN to local var V%02u/%d: ", lhsLclNum, lclDefSsaNum);
if (isNewUniq)
{
printf("new uniq ");
}
vnpPrint(newLhsLclVNPair, 1);
printf("\n");
}
#endif // DEBUG
fgValueNumberLocalStore(tree, lclVarTree, offset, storeSize, rhsVNPair);
}
else if (lclVarTree->HasSsaName())
{
Expand Down