[SCEV] Use m_scev_Mul in a few more places. (NFC) (#163364)

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: #163364

Author: fhahn

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) {

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
@@ -12220,12 +12214,11 @@ 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)) {