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-rw-r--r--llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp126
1 files changed, 92 insertions, 34 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 11e869a..d70e96938 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -4075,18 +4075,11 @@ SDValue DAGCombiner::visitSUB(SDNode *N) {
unsigned BitWidth = VT.getScalarSizeInBits();
SDLoc DL(N);
- auto PeekThroughFreeze = [](SDValue N) {
- if (N->getOpcode() == ISD::FREEZE && N.hasOneUse())
- return N->getOperand(0);
- return N;
- };
-
if (SDValue V = foldSubCtlzNot<EmptyMatchContext>(N, DAG))
return V;
// fold (sub x, x) -> 0
- // FIXME: Refactor this and xor and other similar operations together.
- if (PeekThroughFreeze(N0) == PeekThroughFreeze(N1))
+ if (N0 == N1)
return tryFoldToZero(DL, TLI, VT, DAG, LegalOperations);
// fold (sub c1, c2) -> c3
@@ -6499,19 +6492,21 @@ static unsigned getMinMaxOpcodeForFP(SDValue Operand1, SDValue Operand2,
// It is safe to use FMINNUM_IEEE/FMAXNUM_IEEE if all the operands
// are non NaN values.
if (((CC == ISD::SETLT || CC == ISD::SETLE) && (OrAndOpcode == ISD::OR)) ||
- ((CC == ISD::SETGT || CC == ISD::SETGE) && (OrAndOpcode == ISD::AND)))
+ ((CC == ISD::SETGT || CC == ISD::SETGE) && (OrAndOpcode == ISD::AND))) {
return arebothOperandsNotNan(Operand1, Operand2, DAG) &&
isFMAXNUMFMINNUM_IEEE
? ISD::FMINNUM_IEEE
: ISD::DELETED_NODE;
- else if (((CC == ISD::SETGT || CC == ISD::SETGE) &&
- (OrAndOpcode == ISD::OR)) ||
- ((CC == ISD::SETLT || CC == ISD::SETLE) &&
- (OrAndOpcode == ISD::AND)))
+ }
+
+ if (((CC == ISD::SETGT || CC == ISD::SETGE) && (OrAndOpcode == ISD::OR)) ||
+ ((CC == ISD::SETLT || CC == ISD::SETLE) && (OrAndOpcode == ISD::AND))) {
return arebothOperandsNotNan(Operand1, Operand2, DAG) &&
isFMAXNUMFMINNUM_IEEE
? ISD::FMAXNUM_IEEE
: ISD::DELETED_NODE;
+ }
+
// Both FMINNUM/FMAXNUM and FMINNUM_IEEE/FMAXNUM_IEEE handle quiet
// NaNs in the same way. But, FMINNUM/FMAXNUM and FMINNUM_IEEE/
// FMAXNUM_IEEE handle signaling NaNs differently. If we cannot prove
@@ -6521,24 +6516,24 @@ static unsigned getMinMaxOpcodeForFP(SDValue Operand1, SDValue Operand2,
// we can prove that we do not have any sNaNs, then we can do the
// optimization using FMINNUM_IEEE/FMAXNUM_IEEE for the following
// cases.
- else if (((CC == ISD::SETOLT || CC == ISD::SETOLE) &&
- (OrAndOpcode == ISD::OR)) ||
- ((CC == ISD::SETUGT || CC == ISD::SETUGE) &&
- (OrAndOpcode == ISD::AND)))
+ if (((CC == ISD::SETOLT || CC == ISD::SETOLE) && (OrAndOpcode == ISD::OR)) ||
+ ((CC == ISD::SETUGT || CC == ISD::SETUGE) && (OrAndOpcode == ISD::AND))) {
return isFMAXNUMFMINNUM ? ISD::FMINNUM
- : arebothOperandsNotSNan(Operand1, Operand2, DAG) &&
- isFMAXNUMFMINNUM_IEEE
- ? ISD::FMINNUM_IEEE
- : ISD::DELETED_NODE;
- else if (((CC == ISD::SETOGT || CC == ISD::SETOGE) &&
- (OrAndOpcode == ISD::OR)) ||
- ((CC == ISD::SETULT || CC == ISD::SETULE) &&
- (OrAndOpcode == ISD::AND)))
+ : arebothOperandsNotSNan(Operand1, Operand2, DAG) &&
+ isFMAXNUMFMINNUM_IEEE
+ ? ISD::FMINNUM_IEEE
+ : ISD::DELETED_NODE;
+ }
+
+ if (((CC == ISD::SETOGT || CC == ISD::SETOGE) && (OrAndOpcode == ISD::OR)) ||
+ ((CC == ISD::SETULT || CC == ISD::SETULE) && (OrAndOpcode == ISD::AND))) {
return isFMAXNUMFMINNUM ? ISD::FMAXNUM
- : arebothOperandsNotSNan(Operand1, Operand2, DAG) &&
- isFMAXNUMFMINNUM_IEEE
- ? ISD::FMAXNUM_IEEE
- : ISD::DELETED_NODE;
+ : arebothOperandsNotSNan(Operand1, Operand2, DAG) &&
+ isFMAXNUMFMINNUM_IEEE
+ ? ISD::FMAXNUM_IEEE
+ : ISD::DELETED_NODE;
+ }
+
return ISD::DELETED_NODE;
}
@@ -13184,14 +13179,14 @@ static SDValue combineVSelectWithAllOnesOrZeros(SDValue Cond, SDValue TVal,
// select Cond, -1, x → or Cond, x
if (IsTAllOne) {
- SDValue X = DAG.getBitcast(CondVT, FVal);
+ SDValue X = DAG.getBitcast(CondVT, DAG.getFreeze(FVal));
SDValue Or = DAG.getNode(ISD::OR, DL, CondVT, Cond, X);
return DAG.getBitcast(VT, Or);
}
// select Cond, x, 0 → and Cond, x
if (IsFAllZero) {
- SDValue X = DAG.getBitcast(CondVT, TVal);
+ SDValue X = DAG.getBitcast(CondVT, DAG.getFreeze(TVal));
SDValue And = DAG.getNode(ISD::AND, DL, CondVT, Cond, X);
return DAG.getBitcast(VT, And);
}
@@ -13199,7 +13194,7 @@ static SDValue combineVSelectWithAllOnesOrZeros(SDValue Cond, SDValue TVal,
// select Cond, 0, x -> and not(Cond), x
if (IsTAllZero &&
(isBitwiseNot(peekThroughBitcasts(Cond)) || TLI.hasAndNot(Cond))) {
- SDValue X = DAG.getBitcast(CondVT, FVal);
+ SDValue X = DAG.getBitcast(CondVT, DAG.getFreeze(FVal));
SDValue And =
DAG.getNode(ISD::AND, DL, CondVT, DAG.getNOT(DL, Cond, CondVT), X);
return DAG.getBitcast(VT, And);
@@ -16754,6 +16749,17 @@ SDValue DAGCombiner::visitFREEZE(SDNode *N) {
if (DAG.isGuaranteedNotToBeUndefOrPoison(N0, /*PoisonOnly*/ false))
return N0;
+ // If we have frozen and unfrozen users of N0, update so everything uses N.
+ if (!N0.isUndef() && !N0.hasOneUse()) {
+ SDValue FrozenN0(N, 0);
+ DAG.ReplaceAllUsesOfValueWith(N0, FrozenN0);
+ // ReplaceAllUsesOfValueWith will have also updated the use in N, thus
+ // creating a cycle in a DAG. Let's undo that by mutating the freeze.
+ assert(N->getOperand(0) == FrozenN0 && "Expected cycle in DAG");
+ DAG.UpdateNodeOperands(N, N0);
+ return FrozenN0;
+ }
+
// We currently avoid folding freeze over SRA/SRL, due to the problems seen
// with (freeze (assert ext)) blocking simplifications of SRA/SRL. See for
// example https://reviews.llvm.org/D136529#4120959.
@@ -16807,8 +16813,7 @@ SDValue DAGCombiner::visitFREEZE(SDNode *N) {
SmallSet<SDValue, 8> MaybePoisonOperands;
SmallVector<unsigned, 8> MaybePoisonOperandNumbers;
for (auto [OpNo, Op] : enumerate(N0->ops())) {
- if (DAG.isGuaranteedNotToBeUndefOrPoison(Op, /*PoisonOnly*/ false,
- /*Depth*/ 1))
+ if (DAG.isGuaranteedNotToBeUndefOrPoison(Op, /*PoisonOnly=*/false))
continue;
bool HadMaybePoisonOperands = !MaybePoisonOperands.empty();
bool IsNewMaybePoisonOperand = MaybePoisonOperands.insert(Op).second;
@@ -22534,6 +22539,56 @@ SDValue DAGCombiner::visitATOMIC_STORE(SDNode *N) {
return SDValue();
}
+static SDValue foldToMaskedStore(StoreSDNode *Store, SelectionDAG &DAG,
+ const SDLoc &Dl) {
+ if (!Store->isSimple() || !ISD::isNormalStore(Store))
+ return SDValue();
+
+ SDValue StoredVal = Store->getValue();
+ SDValue StorePtr = Store->getBasePtr();
+ SDValue StoreOffset = Store->getOffset();
+ EVT VT = Store->getMemoryVT();
+ unsigned AddrSpace = Store->getAddressSpace();
+ Align Alignment = Store->getAlign();
+ const TargetLowering &TLI = DAG.getTargetLoweringInfo();
+
+ if (!TLI.isOperationLegalOrCustom(ISD::MSTORE, VT) ||
+ !TLI.allowsMisalignedMemoryAccesses(VT, AddrSpace, Alignment))
+ return SDValue();
+
+ SDValue Mask, OtherVec, LoadCh;
+ unsigned LoadPos;
+ if (sd_match(StoredVal,
+ m_VSelect(m_Value(Mask), m_Value(OtherVec),
+ m_Load(m_Value(LoadCh), m_Specific(StorePtr),
+ m_Specific(StoreOffset))))) {
+ LoadPos = 2;
+ } else if (sd_match(StoredVal,
+ m_VSelect(m_Value(Mask),
+ m_Load(m_Value(LoadCh), m_Specific(StorePtr),
+ m_Specific(StoreOffset)),
+ m_Value(OtherVec)))) {
+ LoadPos = 1;
+ } else {
+ return SDValue();
+ }
+
+ auto *Load = cast<LoadSDNode>(StoredVal.getOperand(LoadPos));
+ if (!Load->isSimple() || !ISD::isNormalLoad(Load) ||
+ Load->getAddressSpace() != AddrSpace)
+ return SDValue();
+
+ if (!Store->getChain().reachesChainWithoutSideEffects(LoadCh))
+ return SDValue();
+
+ if (LoadPos == 1)
+ Mask = DAG.getNOT(Dl, Mask, Mask.getValueType());
+
+ return DAG.getMaskedStore(Store->getChain(), Dl, OtherVec, StorePtr,
+ StoreOffset, Mask, VT, Store->getMemOperand(),
+ Store->getAddressingMode());
+}
+
SDValue DAGCombiner::visitSTORE(SDNode *N) {
StoreSDNode *ST = cast<StoreSDNode>(N);
SDValue Chain = ST->getChain();
@@ -22768,6 +22823,9 @@ SDValue DAGCombiner::visitSTORE(SDNode *N) {
if (SDValue NewSt = splitMergedValStore(ST))
return NewSt;
+ if (SDValue MaskedStore = foldToMaskedStore(ST, DAG, SDLoc(N)))
+ return MaskedStore;
+
return ReduceLoadOpStoreWidth(N);
}
generated by cgit v1.1 at 2025-08-06 09:31:49 +0000