Revert "[SCEV] Improve zext(A /u B) and zext(A % B)"

This reverts commit r335197, as some bots are not happy.

llvm-svn: 335198

1 files changed, 0 insertions, 54 deletions

diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index 609d04bbd7b..705272cd73d 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -1756,20 +1756,6 @@ ScalarEvolution::getZeroExtendExpr(const SCEV *Op, Type *Ty, unsigned Depth) {
       }
     }
 
-  // zext(A % B) --> zext(A) % zext(B)
-  {
-    const SCEV *LHS;
-    const SCEV *RHS;
-    if (matchURem(Op, LHS, RHS))
-      return getURemExpr(getZeroExtendExpr(LHS, Ty, Depth + 1),
-                         getZeroExtendExpr(RHS, Ty, Depth + 1));
-  }
-
-  // zext(A / B) --> zext(A) / zext(B).
-  if (auto *Div = dyn_cast<SCEVUDivExpr>(Op))
-    return getUDivExpr(getZeroExtendExpr(Div->getLHS(), Ty, Depth + 1),
-                       getZeroExtendExpr(Div->getRHS(), Ty, Depth + 1));
-
   if (auto *SA = dyn_cast<SCEVAddExpr>(Op)) {
     // zext((A + B + ...)<nuw>) --> (zext(A) + zext(B) + ...)<nuw>
     if (SA->hasNoUnsignedWrap()) {
@@ -12167,43 +12153,3 @@ void PredicatedScalarEvolution::print(raw_ostream &OS, unsigned Depth) const {
       OS.indent(Depth + 2) << "--> " << *II->second.second << "\n";
     }
 }
-
-// Match the mathematical pattern A - (A / B) * B, where A and B can be
-// arbitrary expressions.
-// It's not always easy, as A and B can be folded (imagine A is X / 2, and B is
-// 4, A / B becomes X / 8).
-bool ScalarEvolution::matchURem(const SCEV *Expr, const SCEV *&LHS,
-                                const SCEV *&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)
-    return false;
-
-  const auto MatchURemWithDivisor = [&](const SCEV *B) {
-    // (SomeExpr + (-(SomeExpr / B) * B)).
-    if (Expr == getURemExpr(A, B)) {
-      LHS = A;
-      RHS = B;
-      return true;
-    }
-    return false;
-  };
-
-  // (SomeExpr + (-1 * (SomeExpr / B) * B)).
-  if (Mul->getNumOperands() == 3 && isa<SCEVConstant>(Mul->getOperand(0)))
-    return MatchURemWithDivisor(Mul->getOperand(1)) ||
-           MatchURemWithDivisor(Mul->getOperand(2));
-
-  // (SomeExpr + ((-SomeExpr / B) * B)) or (SomeExpr + ((SomeExpr / B) * -B)).
-  if (Mul->getNumOperands() == 2)
-    return MatchURemWithDivisor(Mul->getOperand(1)) ||
-           MatchURemWithDivisor(Mul->getOperand(0)) ||
-           MatchURemWithDivisor(getNegativeSCEV(Mul->getOperand(1))) ||
-           MatchURemWithDivisor(getNegativeSCEV(Mul->getOperand(0)));
-  return false;
-};