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[SLP] Revert r296863 due to miscompiles.

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Details and reproducer are on the email thread for r296863.

llvm-svn: 297103
This commit is contained in:
Michael Kuperstein
2017-03-06 23:54:51 +00:00
parent 4af068ea55
commit 768d013a03
5 changed files with 83 additions and 152 deletions
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151
llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
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@@ -423,8 +423,10 @@ private:
/// be vectorized to use the original vector (or aggregate "bitcast" to a vector).
bool canReuseExtract(ArrayRef<Value *> VL, unsigned Opcode) const;
/// Vectorize a single entry in the tree.
Value *vectorizeTree(TreeEntry *E);
/// Vectorize a single entry in the tree. VL icontains all isomorphic scalars
/// in order of its usage in a user program, for example ADD1, ADD2 and so on
/// or LOAD1 , LOAD2 etc.
Value *vectorizeTree(ArrayRef<Value *> VL, TreeEntry *E);
/// Vectorize a single entry in the tree, starting in \p VL.
Value *vectorizeTree(ArrayRef<Value *> VL);
@@ -464,8 +466,8 @@ private:
SmallVectorImpl<Value *> &Left,
SmallVectorImpl<Value *> &Right);
struct TreeEntry {
TreeEntry()
: Scalars(), VectorizedValue(nullptr), NeedToGather(0), ShuffleMask() {}
TreeEntry() : Scalars(), VectorizedValue(nullptr),
NeedToGather(0), NeedToShuffle(0) {}
/// \returns true if the scalars in VL are equal to this entry.
bool isSame(ArrayRef<Value *> VL) const {
@@ -493,23 +495,19 @@ private:
/// Do we need to gather this sequence ?
bool NeedToGather;
/// Records optional suffle mask for jumbled memory accesses in this.
SmallVector<unsigned, 8> ShuffleMask;
/// Do we need to shuffle the load ?
bool NeedToShuffle;
};
/// Create a new VectorizableTree entry.
TreeEntry *newTreeEntry(ArrayRef<Value *> VL, bool Vectorized,
ArrayRef<unsigned> ShuffleMask = None) {
bool NeedToShuffle) {
VectorizableTree.emplace_back();
int idx = VectorizableTree.size() - 1;
TreeEntry *Last = &VectorizableTree[idx];
Last->Scalars.insert(Last->Scalars.begin(), VL.begin(), VL.end());
Last->NeedToGather = !Vectorized;
if (!ShuffleMask.empty())
Last->ShuffleMask.insert(Last->ShuffleMask.begin(), ShuffleMask.begin(),
ShuffleMask.end());
Last->NeedToShuffle = NeedToShuffle;
if (Vectorized) {
for (int i = 0, e = VL.size(); i != e; ++i) {
assert(!ScalarToTreeEntry.count(VL[i]) && "Scalar already in tree!");
@@ -1032,21 +1030,21 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (Depth == RecursionMaxDepth) {
DEBUG(dbgs() << "SLP: Gathering due to max recursion depth.\n");
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
// Don't handle vectors.
if (VL[0]->getType()->isVectorTy()) {
DEBUG(dbgs() << "SLP: Gathering due to vector type.\n");
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
if (SI->getValueOperand()->getType()->isVectorTy()) {
DEBUG(dbgs() << "SLP: Gathering due to store vector type.\n");
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
unsigned Opcode = getSameOpcode(VL);
@@ -1063,7 +1061,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
// If all of the operands are identical or constant we have a simple solution.
if (allConstant(VL) || isSplat(VL) || !allSameBlock(VL) || !Opcode) {
DEBUG(dbgs() << "SLP: Gathering due to C,S,B,O. \n");
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
@@ -1075,7 +1073,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (EphValues.count(VL[i])) {
DEBUG(dbgs() << "SLP: The instruction (" << *VL[i] <<
") is ephemeral.\n");
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
}
@@ -1088,7 +1086,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
DEBUG(dbgs() << "SLP: \tChecking bundle: " << *VL[i] << ".\n");
if (E->Scalars[i] != VL[i]) {
DEBUG(dbgs() << "SLP: Gathering due to partial overlap.\n");
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
}
@@ -1101,7 +1099,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (ScalarToTreeEntry.count(VL[i])) {
DEBUG(dbgs() << "SLP: The instruction (" << *VL[i] <<
") is already in tree.\n");
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
}
@@ -1111,7 +1109,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
for (unsigned i = 0, e = VL.size(); i != e; ++i) {
if (MustGather.count(VL[i])) {
DEBUG(dbgs() << "SLP: Gathering due to gathered scalar.\n");
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
}
@@ -1125,7 +1123,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
// Don't go into unreachable blocks. They may contain instructions with
// dependency cycles which confuse the final scheduling.
DEBUG(dbgs() << "SLP: bundle in unreachable block.\n");
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
@@ -1134,7 +1132,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
for (unsigned j = i+1; j < e; ++j)
if (VL[i] == VL[j]) {
DEBUG(dbgs() << "SLP: Scalar used twice in bundle.\n");
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
@@ -1149,7 +1147,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
assert((!BS.getScheduleData(VL[0]) ||
!BS.getScheduleData(VL[0])->isPartOfBundle()) &&
"tryScheduleBundle should cancelScheduling on failure");
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
DEBUG(dbgs() << "SLP: We are able to schedule this bundle.\n");
@@ -1166,12 +1164,12 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (Term) {
DEBUG(dbgs() << "SLP: Need to swizzle PHINodes (TerminatorInst use).\n");
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
}
newTreeEntry(VL, true);
newTreeEntry(VL, true, false);
DEBUG(dbgs() << "SLP: added a vector of PHINodes.\n");
for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
@@ -1193,7 +1191,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
} else {
BS.cancelScheduling(VL);
}
newTreeEntry(VL, Reuse);
newTreeEntry(VL, Reuse, false);
return;
}
case Instruction::Load: {
@@ -1209,7 +1207,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (DL->getTypeSizeInBits(ScalarTy) !=
DL->getTypeAllocSizeInBits(ScalarTy)) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
DEBUG(dbgs() << "SLP: Gathering loads of non-packed type.\n");
return;
}
@@ -1220,7 +1218,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
LoadInst *L = cast<LoadInst>(VL[i]);
if (!L->isSimple()) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
DEBUG(dbgs() << "SLP: Gathering non-simple loads.\n");
return;
}
@@ -1240,7 +1238,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (Consecutive) {
++NumLoadsWantToKeepOrder;
newTreeEntry(VL, true);
newTreeEntry(VL, true, false);
DEBUG(dbgs() << "SLP: added a vector of loads.\n");
return;
}
@@ -1257,8 +1255,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (VL.size() > 2 && !ReverseConsecutive) {
bool ShuffledLoads = true;
SmallVector<Value *, 8> Sorted;
SmallVector<unsigned, 4> Mask;
if (sortMemAccesses(VL, *DL, *SE, Sorted, &Mask)) {
if (sortMemAccesses(VL, *DL, *SE, Sorted)) {
auto NewVL = makeArrayRef(Sorted.begin(), Sorted.end());
for (unsigned i = 0, e = NewVL.size() - 1; i < e; ++i) {
if (!isConsecutiveAccess(NewVL[i], NewVL[i + 1], *DL, *SE)) {
@@ -1267,14 +1264,14 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
}
}
if (ShuffledLoads) {
newTreeEntry(NewVL, true, makeArrayRef(Mask.begin(), Mask.end()));
newTreeEntry(NewVL, true, true);
return;
}
}
}
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
if (ReverseConsecutive) {
++NumLoadsWantToChangeOrder;
@@ -1301,12 +1298,12 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
Type *Ty = cast<Instruction>(Val)->getOperand(0)->getType();
if (Ty != SrcTy || !isValidElementType(Ty)) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
DEBUG(dbgs() << "SLP: Gathering casts with different src types.\n");
return;
}
}
newTreeEntry(VL, true);
newTreeEntry(VL, true, false);
DEBUG(dbgs() << "SLP: added a vector of casts.\n");
for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
@@ -1329,13 +1326,13 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (Cmp->getPredicate() != P0 ||
Cmp->getOperand(0)->getType() != ComparedTy) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
DEBUG(dbgs() << "SLP: Gathering cmp with different predicate.\n");
return;
}
}
newTreeEntry(VL, true);
newTreeEntry(VL, true, false);
DEBUG(dbgs() << "SLP: added a vector of compares.\n");
for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
@@ -1367,7 +1364,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
newTreeEntry(VL, true);
newTreeEntry(VL, true, false);
DEBUG(dbgs() << "SLP: added a vector of bin op.\n");
// Sort operands of the instructions so that each side is more likely to
@@ -1396,7 +1393,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (cast<Instruction>(Val)->getNumOperands() != 2) {
DEBUG(dbgs() << "SLP: not-vectorizable GEP (nested indexes).\n");
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
}
@@ -1409,7 +1406,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (Ty0 != CurTy) {
DEBUG(dbgs() << "SLP: not-vectorizable GEP (different types).\n");
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
}
@@ -1421,12 +1418,12 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
DEBUG(
dbgs() << "SLP: not-vectorizable GEP (non-constant indexes).\n");
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
return;
}
}
newTreeEntry(VL, true);
newTreeEntry(VL, true, false);
DEBUG(dbgs() << "SLP: added a vector of GEPs.\n");
for (unsigned i = 0, e = 2; i < e; ++i) {
ValueList Operands;
@@ -1443,12 +1440,12 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
for (unsigned i = 0, e = VL.size() - 1; i < e; ++i)
if (!isConsecutiveAccess(VL[i], VL[i + 1], *DL, *SE)) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
DEBUG(dbgs() << "SLP: Non-consecutive store.\n");
return;
}
newTreeEntry(VL, true);
newTreeEntry(VL, true, false);
DEBUG(dbgs() << "SLP: added a vector of stores.\n");
ValueList Operands;
@@ -1466,7 +1463,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
Intrinsic::ID ID = getVectorIntrinsicIDForCall(CI, TLI);
if (!isTriviallyVectorizable(ID)) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
DEBUG(dbgs() << "SLP: Non-vectorizable call.\n");
return;
}
@@ -1480,7 +1477,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
getVectorIntrinsicIDForCall(CI2, TLI) != ID ||
!CI->hasIdenticalOperandBundleSchema(*CI2)) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
DEBUG(dbgs() << "SLP: mismatched calls:" << *CI << "!=" << *VL[i]
<< "\n");
return;
@@ -1491,7 +1488,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
Value *A1J = CI2->getArgOperand(1);
if (A1I != A1J) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
DEBUG(dbgs() << "SLP: mismatched arguments in call:" << *CI
<< " argument "<< A1I<<"!=" << A1J
<< "\n");
@@ -1504,14 +1501,14 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
CI->op_begin() + CI->getBundleOperandsEndIndex(),
CI2->op_begin() + CI2->getBundleOperandsStartIndex())) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
DEBUG(dbgs() << "SLP: mismatched bundle operands in calls:" << *CI << "!="
<< *VL[i] << '\n');
return;
}
}
newTreeEntry(VL, true);
newTreeEntry(VL, true, false);
for (unsigned i = 0, e = CI->getNumArgOperands(); i != e; ++i) {
ValueList Operands;
// Prepare the operand vector.
@@ -1528,11 +1525,11 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
// then do not vectorize this instruction.
if (!isAltShuffle) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
DEBUG(dbgs() << "SLP: ShuffleVector are not vectorized.\n");
return;
}
newTreeEntry(VL, true);
newTreeEntry(VL, true, false);
DEBUG(dbgs() << "SLP: added a ShuffleVector op.\n");
// Reorder operands if reordering would enable vectorization.
@@ -1556,7 +1553,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
}
default:
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
newTreeEntry(VL, false, false);
DEBUG(dbgs() << "SLP: Gathering unknown instruction.\n");
return;
}
@@ -1795,7 +1792,7 @@ int BoUpSLP::getEntryCost(TreeEntry *E) {
TTI->getMemoryOpCost(Instruction::Load, ScalarTy, alignment, 0);
int VecLdCost = TTI->getMemoryOpCost(Instruction::Load,
VecTy, alignment, 0);
if (!E->ShuffleMask.empty()) {
if (E->NeedToShuffle) {
VecLdCost += TTI->getShuffleCost(
TargetTransformInfo::SK_PermuteSingleSrc, VecTy, 0);
}
@@ -2361,9 +2358,8 @@ Value *BoUpSLP::vectorizeTree(ArrayRef<Value *> VL) {
if (ScalarToTreeEntry.count(VL[0])) {
int Idx = ScalarToTreeEntry[VL[0]];
TreeEntry *E = &VectorizableTree[Idx];
if (E->isSame(VL) ||
(!E->ShuffleMask.empty() && E->isFoundJumbled(VL, *DL, *SE)))
return vectorizeTree(E);
if (E->isSame(VL) || (E->NeedToShuffle && E->isFoundJumbled(VL, *DL, *SE)))
return vectorizeTree(VL, E);
}
Type *ScalarTy = VL[0]->getType();
@@ -2374,10 +2370,10 @@ Value *BoUpSLP::vectorizeTree(ArrayRef<Value *> VL) {
return Gather(VL, VecTy);
}
Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
Value *BoUpSLP::vectorizeTree(ArrayRef<Value *> VL, TreeEntry *E) {
IRBuilder<>::InsertPointGuard Guard(Builder);
if (E->VectorizedValue && E->ShuffleMask.empty()) {
if (E->VectorizedValue && !E->NeedToShuffle) {
DEBUG(dbgs() << "SLP: Diamond merged for " << *E->Scalars[0] << ".\n");
return E->VectorizedValue;
}
@@ -2615,18 +2611,27 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
// As program order of scalar loads are jumbled, the vectorized 'load'
// must be followed by a 'shuffle' with the required jumbled mask.
if (!E->ShuffleMask.empty()) {
if (!VL.empty() && (E->NeedToShuffle)) {
assert(VL.size() == E->Scalars.size() &&
"Equal number of scalars expected");
SmallVector<Constant *, 8> Mask;
for (unsigned Lane = 0, LE = E->ShuffleMask.size(); Lane != LE;
++Lane) {
Mask.push_back(Builder.getInt32(E->ShuffleMask[Lane]));
for (Value *Val : VL) {
if (ScalarToTreeEntry.count(Val)) {
int Idx = ScalarToTreeEntry[Val];
TreeEntry *E = &VectorizableTree[Idx];
for (unsigned Lane = 0, LE = VL.size(); Lane != LE; ++Lane) {
if (E->Scalars[Lane] == Val) {
Mask.push_back(Builder.getInt32(Lane));
break;
}
}
}
}
// Generate shuffle for jumbled memory access
Value *Undef = UndefValue::get(VecTy);
Value *Shuf = Builder.CreateShuffleVector((Value *)LI, Undef,
ConstantVector::get(Mask));
E->VectorizedValue = Shuf;
++NumVectorInstructions;
return Shuf;
}
@@ -2811,7 +2816,7 @@ BoUpSLP::vectorizeTree(ExtraValueToDebugLocsMap &ExternallyUsedValues) {
}
Builder.SetInsertPoint(&F->getEntryBlock().front());
auto *VectorRoot = vectorizeTree(&VectorizableTree[0]);
auto *VectorRoot = vectorizeTree(ArrayRef<Value *>(), &VectorizableTree[0]);
// If the vectorized tree can be rewritten in a smaller type, we truncate the
// vectorized root. InstCombine will then rewrite the entire expression. We
@@ -2856,20 +2861,8 @@ BoUpSLP::vectorizeTree(ExtraValueToDebugLocsMap &ExternallyUsedValues) {
Value *Vec = E->VectorizedValue;
assert(Vec && "Can't find vectorizable value");
unsigned i = 0;
Value *Lane;
// In case vectorizable scalars use are not in-order, scalars would have
// been shuffled.Recompute the proper Lane of ExternalUse.
if (!E->ShuffleMask.empty()) {
SmallVector<unsigned, 4> Val(E->ShuffleMask.size());
for (; i < E->ShuffleMask.size(); i++) {
if (E->ShuffleMask[i] == (unsigned)ExternalUse.Lane)
break;
}
Lane = Builder.getInt32(i);
} else {
Lane = Builder.getInt32(ExternalUse.Lane);
}
Value *Lane = Builder.getInt32(ExternalUse.Lane);
// If User == nullptr, the Scalar is used as extra arg. Generate
// ExtractElement instruction and update the record for this scalar in
// ExternallyUsedValues.