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[LV] Explicitly disable in-loop reductions for AnyOf and FindIV. nfc #163541

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[LV] Explicitly disable in-loop reductions for AnyOf and FindIV. nfc #163541

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12 changes: 7 additions & 5 deletions llvm/lib/Analysis/IVDescriptors.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1220,11 +1220,6 @@ unsigned RecurrenceDescriptor::getOpcode(RecurKind Kind) {
return Instruction::Add;
case RecurKind::Mul:
return Instruction::Mul;
case RecurKind::AnyOf:
case RecurKind::FindFirstIVSMin:
case RecurKind::FindFirstIVUMin:
case RecurKind::FindLastIVSMax:
case RecurKind::FindLastIVUMax:
case RecurKind::Or:
return Instruction::Or;
case RecurKind::And:
Expand All @@ -1248,6 +1243,13 @@ unsigned RecurrenceDescriptor::getOpcode(RecurKind Kind) {
case RecurKind::FMaximumNum:
case RecurKind::FMinimumNum:
return Instruction::FCmp;
case RecurKind::AnyOf:
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Could we still leave AnyOf to return Or to avoid the changes in llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp?

case RecurKind::FindFirstIVSMin:
case RecurKind::FindFirstIVUMin:
case RecurKind::FindLastIVSMax:
case RecurKind::FindLastIVUMax:
// TODO: Set AnyOf and FindIV to Instruction::Select once in-loop reductions
// are supported.
default:
llvm_unreachable("Unknown recurrence operation");
}
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7 changes: 6 additions & 1 deletion llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
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Expand Up @@ -6515,9 +6515,14 @@ void LoopVectorizationCostModel::collectInLoopReductions() {
if (RdxDesc.getRecurrenceType() != Phi->getType())
continue;

// In-loop AnyOf and FindIV reductions are not yet supported.
RecurKind Kind = RdxDesc.getRecurrenceKind();
if (RecurrenceDescriptor::isAnyOfRecurrenceKind(Kind) ||
RecurrenceDescriptor::isFindIVRecurrenceKind(Kind))
continue;

// If the target would prefer this reduction to happen "in-loop", then we
// want to record it as such.
RecurKind Kind = RdxDesc.getRecurrenceKind();
if (!PreferInLoopReductions && !useOrderedReductions(RdxDesc) &&
!TTI.preferInLoopReduction(Kind, Phi->getType()))
continue;
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7 changes: 3 additions & 4 deletions llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
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Expand Up @@ -784,10 +784,9 @@ Value *VPInstruction::generate(VPTransformState &State) {
auto *OrigPhi = cast<PHINode>(PhiR->getUnderlyingValue());
Value *ReducedPartRdx = State.get(getOperand(2));
for (unsigned Idx = 3; Idx < getNumOperands(); ++Idx)
ReducedPartRdx = Builder.CreateBinOp(
(Instruction::BinaryOps)RecurrenceDescriptor::getOpcode(
RecurKind::AnyOf),
State.get(getOperand(Idx)), ReducedPartRdx, "bin.rdx");
ReducedPartRdx =
Builder.CreateBinOp(Instruction::Or, State.get(getOperand(Idx)),
ReducedPartRdx, "bin.rdx");
return createAnyOfReduction(Builder, ReducedPartRdx,
State.get(getOperand(1), VPLane(0)), OrigPhi);
}
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