[llvm] cfd0f41 - [SLP][NFC]Make collectValuesToDemote member of BoUpSLP to avoid using
Alexey Bataev via llvm-commits
llvm-commits at lists.llvm.org
Fri Nov 17 08:05:22 PST 2023
Author: Alexey Bataev
Date: 2023-11-17T08:05:02-08:00
New Revision: cfd0f41f4effb5d31654dcb28c1a577c152ee23b
URL: https://github.com/llvm/llvm-project/commit/cfd0f41f4effb5d31654dcb28c1a577c152ee23b
DIFF: https://github.com/llvm/llvm-project/commit/cfd0f41f4effb5d31654dcb28c1a577c152ee23b.diff
LOG: [SLP][NFC]Make collectValuesToDemote member of BoUpSLP to avoid using
Expr container, NFC.
Saves the memory and may improve compile time.
Added:
Modified:
llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
Removed:
################################################################################
diff --git a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
index fca9649193e5a9e..bff3e49b14bc6bc 100644
--- a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -2285,6 +2285,14 @@ class BoUpSLP {
~BoUpSLP();
private:
+ /// Determine if a vectorized value \p V in can be demoted to
+ /// a smaller type with a truncation. We collect the values that will be
+ /// demoted in ToDemote and additional roots that require investigating in
+ /// Roots.
+ bool collectValuesToDemote(Value *V, SmallVectorImpl<Value *> &ToDemote,
+ SmallVectorImpl<Value *> &Roots,
+ DenseSet<Value *> &Visited) const;
+
/// Check if the operands on the edges \p Edges of the \p UserTE allows
/// reordering (i.e. the operands can be reordered because they have only one
/// user and reordarable).
@@ -13060,19 +13068,20 @@ unsigned BoUpSLP::getVectorElementSize(Value *V) {
// Determine if a value V in a vectorizable expression Expr can be demoted to a
// smaller type with a truncation. We collect the values that will be demoted
// in ToDemote and additional roots that require investigating in Roots.
-static bool collectValuesToDemote(Value *V, SmallPtrSetImpl<Value *> &Expr,
- SmallVectorImpl<Value *> &ToDemote,
- SmallVectorImpl<Value *> &Roots) {
+bool BoUpSLP::collectValuesToDemote(Value *V,
+ SmallVectorImpl<Value *> &ToDemote,
+ SmallVectorImpl<Value *> &Roots,
+ DenseSet<Value *> &Visited) const {
// We can always demote constants.
if (isa<Constant>(V)) {
ToDemote.push_back(V);
return true;
}
- // If the value is not an instruction in the expression with only one use, it
- // cannot be demoted.
+ // If the value is not a vectorized instruction in the expression with only
+ // one use, it cannot be demoted.
auto *I = dyn_cast<Instruction>(V);
- if (!I || !I->hasOneUse() || !Expr.count(I))
+ if (!I || !I->hasOneUse() || !getTreeEntry(I) || !Visited.insert(I).second)
return false;
switch (I->getOpcode()) {
@@ -13096,16 +13105,16 @@ static bool collectValuesToDemote(Value *V, SmallPtrSetImpl<Value *> &Expr,
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
- if (!collectValuesToDemote(I->getOperand(0), Expr, ToDemote, Roots) ||
- !collectValuesToDemote(I->getOperand(1), Expr, ToDemote, Roots))
+ if (!collectValuesToDemote(I->getOperand(0), ToDemote, Roots, Visited) ||
+ !collectValuesToDemote(I->getOperand(1), ToDemote, Roots, Visited))
return false;
break;
// We can demote selects if we can demote their true and false values.
case Instruction::Select: {
SelectInst *SI = cast<SelectInst>(I);
- if (!collectValuesToDemote(SI->getTrueValue(), Expr, ToDemote, Roots) ||
- !collectValuesToDemote(SI->getFalseValue(), Expr, ToDemote, Roots))
+ if (!collectValuesToDemote(SI->getTrueValue(), ToDemote, Roots, Visited) ||
+ !collectValuesToDemote(SI->getFalseValue(), ToDemote, Roots, Visited))
return false;
break;
}
@@ -13115,7 +13124,7 @@ static bool collectValuesToDemote(Value *V, SmallPtrSetImpl<Value *> &Expr,
case Instruction::PHI: {
PHINode *PN = cast<PHINode>(I);
for (Value *IncValue : PN->incoming_values())
- if (!collectValuesToDemote(IncValue, Expr, ToDemote, Roots))
+ if (!collectValuesToDemote(IncValue, ToDemote, Roots, Visited))
return false;
break;
}
@@ -13142,36 +13151,16 @@ void BoUpSLP::computeMinimumValueSizes() {
if (!TreeRootIT)
return;
- // If the expression is not rooted by a store, these roots should have
- // external uses.
- // TOSO: investigate if this can be relaxed.
- SmallPtrSet<Value *, 32> Expr(TreeRoot.begin(), TreeRoot.end());
- for (auto &EU : ExternalUses)
- if (!Expr.erase(EU.Scalar))
- return;
- if (!Expr.empty())
- return;
-
- // Collect the scalar values of the vectorizable expression. We will use this
- // context to determine which values can be demoted. If we see a truncation,
- // we mark it as seeding another demotion.
- for (auto &EntryPtr : VectorizableTree)
- Expr.insert(EntryPtr->Scalars.begin(), EntryPtr->Scalars.end());
-
- // Ensure the roots of the vectorizable tree don't form a cycle. They must
- // have a single external user that is not in the vectorizable tree.
- for (auto *Root : TreeRoot)
- if (!Root->hasOneUse() || Expr.count(*Root->user_begin()))
- return;
-
// Conservatively determine if we can actually truncate the roots of the
// expression. Collect the values that can be demoted in ToDemote and
// additional roots that require investigating in Roots.
SmallVector<Value *, 32> ToDemote;
SmallVector<Value *, 4> Roots;
- for (auto *Root : TreeRoot)
- if (!collectValuesToDemote(Root, Expr, ToDemote, Roots))
+ for (auto *Root : TreeRoot) {
+ DenseSet<Value *> Visited;
+ if (!collectValuesToDemote(Root, ToDemote, Roots, Visited))
return;
+ }
// The maximum bit width required to represent all the values that can be
// demoted without loss of precision. It would be safe to truncate the roots
@@ -13201,9 +13190,9 @@ void BoUpSLP::computeMinimumValueSizes() {
// maximum bit width required to store the scalar by using ValueTracking to
// compute the number of high-order bits we can truncate.
if (MaxBitWidth == DL->getTypeSizeInBits(TreeRoot[0]->getType()) &&
- llvm::all_of(TreeRoot, [](Value *R) {
- assert(R->hasOneUse() && "Root should have only one use!");
- return isa<GetElementPtrInst>(R->user_back());
+ all_of(TreeRoot, [](Value *V) {
+ return all_of(V->users(),
+ [](User *U) { return isa<GetElementPtrInst>(U); });
})) {
MaxBitWidth = 8u;
@@ -13252,8 +13241,10 @@ void BoUpSLP::computeMinimumValueSizes() {
// If we can truncate the root, we must collect additional values that might
// be demoted as a result. That is, those seeded by truncations we will
// modify.
- while (!Roots.empty())
- collectValuesToDemote(Roots.pop_back_val(), Expr, ToDemote, Roots);
+ while (!Roots.empty()) {
+ DenseSet<Value *> Visited;
+ collectValuesToDemote(Roots.pop_back_val(), ToDemote, Roots, Visited);
+ }
// Finally, map the values we can demote to the maximum bit with we computed.
DenseMap<const TreeEntry *, bool> Signendness;
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