[SCEV] Use m_scev_Mul in a few more places. (NFC) #163364
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Add a new variant of m_scev_Mul that binds a SCEVMulExpr and use it in SCEVURem_match and also update 2 more places in ScalarEvolution.cpp that can use m_scev_Mul as well.
llvmbot
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@llvm/pr-subscribers-llvm-analysis Author: Florian Hahn (fhahn) ChangesAdd a new variant of m_scev_Mul that binds a SCEVMulExpr and use it in SCEVURem_match and also update 2 more places in ScalarEvolution.cpp that can use m_scev_Mul as well. Full diff: https://github.com/llvm/llvm-project/pull/163364.diff 2 Files Affected:
diff --git a/llvm/include/llvm/Analysis/ScalarEvolutionPatternMatch.h b/llvm/include/llvm/Analysis/ScalarEvolutionPatternMatch.h
index 871028de3163c..68198ec9b8a9f 100644
--- a/llvm/include/llvm/Analysis/ScalarEvolutionPatternMatch.h
+++ b/llvm/include/llvm/Analysis/ScalarEvolutionPatternMatch.h
@@ -95,6 +95,10 @@ inline bind_ty<const SCEVAddExpr> m_scev_Add(const SCEVAddExpr *&V) {
return V;
}
+inline bind_ty<const SCEVMulExpr> m_scev_Mul(const SCEVMulExpr *&V) {
+ return V;
+}
+
/// Match a specified const SCEV *.
struct specificscev_ty {
const SCEV *Expr;
@@ -284,14 +288,10 @@ template <typename Op0_t, typename Op1_t> struct SCEVURem_match {
<< SE.getTypeSizeInBits(TruncTy));
return Op0.match(LHS) && Op1.match(RHS);
}
- const auto *Add = dyn_cast<SCEVAddExpr>(Expr);
- if (Add == nullptr || Add->getNumOperands() != 2)
- return false;
-
- const SCEV *A = Add->getOperand(1);
- const auto *Mul = dyn_cast<SCEVMulExpr>(Add->getOperand(0));
- if (Mul == nullptr)
+ const SCEV *A;
+ const SCEVMulExpr *Mul;
+ if (!SCEVPatternMatch::match(Expr, m_scev_Add(m_scev_Mul(Mul), m_SCEV(A))))
return false;
const auto MatchURemWithDivisor = [&](const SCEV *B) {
diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index 3fab6b0572cb7..99a580be28d0f 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -4623,17 +4623,11 @@ const SCEV *ScalarEvolution::getNegativeSCEV(const SCEV *V,
/// If Expr computes ~A, return A else return nullptr
static const SCEV *MatchNotExpr(const SCEV *Expr) {
- const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(Expr);
- if (!Add || Add->getNumOperands() != 2 ||
- !Add->getOperand(0)->isAllOnesValue())
- return nullptr;
-
- const SCEVMulExpr *AddRHS = dyn_cast<SCEVMulExpr>(Add->getOperand(1));
- if (!AddRHS || AddRHS->getNumOperands() != 2 ||
- !AddRHS->getOperand(0)->isAllOnesValue())
- return nullptr;
-
- return AddRHS->getOperand(1);
+ const SCEV *MulOp;
+ if (match(Expr, m_scev_Add(m_scev_AllOnes(),
+ m_scev_Mul(m_scev_AllOnes(), m_SCEV(MulOp)))))
+ return MulOp;
+ return nullptr;
}
/// Return a SCEV corresponding to ~V = -1-V
@@ -12210,12 +12204,11 @@ ScalarEvolution::computeConstantDifference(const SCEV *More, const SCEV *Less) {
// Try to match a common constant multiply.
auto MatchConstMul =
[](const SCEV *S) -> std::optional<std::pair<const SCEV *, APInt>> {
- auto *M = dyn_cast<SCEVMulExpr>(S);
- if (!M || M->getNumOperands() != 2 ||
- !isa<SCEVConstant>(M->getOperand(0)))
- return std::nullopt;
- return {
- {M->getOperand(1), cast<SCEVConstant>(M->getOperand(0))->getAPInt()}};
+ const APInt *C;
+ const SCEV *Op;
+ if (match(S, m_scev_Mul(m_scev_APInt(C), m_SCEV(Op))))
+ return {{Op, *C}};
+ return std::nullopt;
};
if (auto MatchedMore = MatchConstMul(More)) {
if (auto MatchedLess = MatchConstMul(Less)) {
|
nikic
approved these changes
Oct 14, 2025
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Oct 16, 2025
Add a new variant of m_scev_Mul that binds a SCEVMulExpr and use it in SCEVURem_match and also update 2 more places in ScalarEvolution.cpp that can use m_scev_Mul as well. PR: llvm/llvm-project#163364
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/65/builds/24095 Here is the relevant piece of the build log for the reference |
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Add a new variant of m_scev_Mul that binds a SCEVMulExpr and use it in SCEVURem_match and also update 2 more places in ScalarEvolution.cpp that can use m_scev_Mul as well.