Revert "Added support for modulo expressions"

This reverts commit 215684. The intention of the commit is great, but
unfortunately it seems to be the cause of 14 LNT test suite failures:

http://lab.llvm.org:8011/builders/perf-x86_64-penryn-O3-polly/builds/116

To make our buildbots and performance testers green until this issue is solved,
we temporarily revert this commit.

llvm-svn: 215816

1 files changed, 4 insertions, 49 deletions

diff --git a/polly/lib/Support/SCEVValidator.cpp b/polly/lib/Support/SCEVValidator.cpp
index e11c9e09fcf..3a8895f6cad 100644
--- a/polly/lib/Support/SCEVValidator.cpp
+++ b/polly/lib/Support/SCEVValidator.cpp
@@ -82,7 +82,7 @@ public:
   std::vector<const SCEV *> getParameters() { return Parameters; }
 
   /// @brief Add the parameters of Source to this result.
-  void addParamsFrom(const ValidatorResult &Source) {
+  void addParamsFrom(class ValidatorResult &Source) {
     Parameters.insert(Parameters.end(), Source.Parameters.begin(),
                       Source.Parameters.end());
   }
@@ -91,10 +91,9 @@ public:
   ///
   /// This means to merge the parameters and to set the Type to the most
   /// specific Type that matches both.
-  ValidatorResult &merge(const ValidatorResult &ToMerge) {
+  void merge(class ValidatorResult &ToMerge) {
     Type = std::max(Type, ToMerge.Type);
     addParamsFrom(ToMerge);
-    return *this;
   }
 
   void print(raw_ostream &OS) {
@@ -157,37 +156,8 @@ public:
   }
 
   class ValidatorResult visitZeroExtendExpr(const SCEVZeroExtendExpr *Expr) {
+    ValidatorResult Op = visit(Expr->getOperand());
 
-    // Pattern matching rules to capture some bit and modulo computations:
-    //
-    //       EXP   %  2^C      <==>
-    // [A] (i + c) & (2^C - 1)  ==> zext iC {c,+,1}<%for_i> to IXX
-    // [B] (p + q) & (2^C - 1)  ==> zext iC (trunc iXX %p_add_q to iC) to iXX
-    // [C] (i + p) & (2^C - 1)  ==> zext iC {p & (2^C - 1),+,1}<%for_i> to iXX
-    //                          ==> zext iC {trunc iXX %p to iC,+,1}<%for_i> to
-
-    // Check for [A] and [C].
-    const SCEV *OpS = Expr->getOperand();
-    if (auto *OpAR = dyn_cast<SCEVAddRecExpr>(OpS)) {
-      const SCEV *OpARStart = OpAR->getStart();
-
-      // Special case for [C].
-      if (auto *OpARStartTR = dyn_cast<SCEVTruncateExpr>(OpARStart))
-        OpARStart = OpARStartTR->getOperand();
-
-      ValidatorResult OpARStartVR = visit(OpARStart);
-      if (OpARStartVR.isConstant() && OpAR->getStepRecurrence(SE)->isOne())
-        return OpARStartVR;
-    }
-
-    // Check for [B].
-    if (auto *OpTR = dyn_cast<SCEVTruncateExpr>(OpS)) {
-      ValidatorResult OpTRVR = visit(OpTR->getOperand());
-      if (OpTRVR.isConstant())
-        return OpTRVR;
-    }
-
-    ValidatorResult Op = visit(OpS);
     switch (Op.getType()) {
     case SCEVType::INT:
     case SCEVType::PARAM:
@@ -376,27 +346,12 @@ public:
       return ValidatorResult(SCEVType::INVALID);
     }
 
-    if (auto *I = dyn_cast<Instruction>(Expr->getValue())) {
-      if (I->getOpcode() == Instruction::SRem) {
-
-        ValidatorResult Op0 = visit(SE.getSCEV(I->getOperand(0)));
-        if (!Op0.isValid())
-          return ValidatorResult(SCEVType::INVALID);
-
-        ValidatorResult Op1 = visit(SE.getSCEV(I->getOperand(1)));
-        if (!Op1.isValid() || !Op1.isINT())
-          return ValidatorResult(SCEVType::INVALID);
-
-        Op0.merge(Op1);
-        return Op0;
-      }
-
+    if (Instruction *I = dyn_cast<Instruction>(Expr->getValue()))
       if (R->contains(I)) {
         DEBUG(dbgs() << "INVALID: UnknownExpr references an instruction "
                         "within the region\n");
         return ValidatorResult(SCEVType::INVALID);
       }
-    }
 
     if (BaseAddress == V) {
       DEBUG(dbgs() << "INVALID: UnknownExpr references BaseAddress\n");