This reverts commit r265913 and r265912

See PR27315

r265913: "[IndVars] Eliminate op.with.overflow when possible"

r265912: "[SCEV] See through op.with.overflow intrinsics"
llvm-svn: 265950

1 files changed, 5 insertions, 49 deletions

diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index 6366e3621ae..654a766b416 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -3831,7 +3831,7 @@ struct BinaryOp {
 
 
 /// Try to map \p V into a BinaryOp, and return \c None on failure.
-static Optional<BinaryOp> MatchBinaryOp(Value *V, DominatorTree &DT) {
+static Optional<BinaryOp> MatchBinaryOp(Value *V) {
   auto *Op = dyn_cast<Operator>(V);
   if (!Op)
     return None;
@@ -3877,50 +3877,6 @@ static Optional<BinaryOp> MatchBinaryOp(Value *V, DominatorTree &DT) {
     }
     return BinaryOp(Op);
 
-  case Instruction::ExtractValue: {
-    auto *EVI = cast<ExtractValueInst>(Op);
-    if (EVI->getNumIndices() != 1 || EVI->getIndices()[0] != 0)
-      break;
-
-    auto *CI = dyn_cast<CallInst>(EVI->getAggregateOperand());
-    if (!CI)
-      break;
-
-    if (auto *F = CI->getCalledFunction())
-      switch (F->getIntrinsicID()) {
-      case Intrinsic::sadd_with_overflow:
-      case Intrinsic::uadd_with_overflow: {
-        if (!isOverflowIntrinsicNoWrap(cast<IntrinsicInst>(CI), DT))
-          return BinaryOp(Instruction::Add, CI->getArgOperand(0),
-                          CI->getArgOperand(1));
-
-        // Now that we know that all uses of the arithmetic-result component of
-        // CI are guarded by the overflow check, we can go ahead and pretend
-        // that the arithmetic is non-overflowing.
-        if (F->getIntrinsicID() == Intrinsic::sadd_with_overflow)
-          return BinaryOp(Instruction::Add, CI->getArgOperand(0),
-                          CI->getArgOperand(1), /* IsNSW = */ true,
-                          /* IsNUW = */ false);
-        else
-          return BinaryOp(Instruction::Add, CI->getArgOperand(0),
-                          CI->getArgOperand(1), /* IsNSW = */ false,
-                          /* IsNUW*/ true);
-      }
-
-      case Intrinsic::ssub_with_overflow:
-      case Intrinsic::usub_with_overflow:
-        return BinaryOp(Instruction::Sub, CI->getArgOperand(0),
-                        CI->getArgOperand(1));
-
-      case Intrinsic::smul_with_overflow:
-      case Intrinsic::umul_with_overflow:
-        return BinaryOp(Instruction::Mul, CI->getArgOperand(0),
-                        CI->getArgOperand(1));
-      default:
-        break;
-      }
-  }
-
   default:
     break;
   }
@@ -3997,7 +3953,7 @@ const SCEV *ScalarEvolution::createAddRecFromPHI(PHINode *PN) {
 
           // If the increment doesn't overflow, then neither the addrec nor
           // the post-increment will overflow.
-          if (auto BO = MatchBinaryOp(BEValueV, DT)) {
+          if (auto BO = MatchBinaryOp(BEValueV)) {
             if (BO->Opcode == Instruction::Add && BO->LHS == PN) {
               if (BO->IsNUW)
                 Flags = setFlags(Flags, SCEV::FlagNUW);
@@ -4877,7 +4833,7 @@ const SCEV *ScalarEvolution::createSCEV(Value *V) {
     return getUnknown(V);
 
   Operator *U = cast<Operator>(V);
-  if (auto BO = MatchBinaryOp(U, DT)) {
+  if (auto BO = MatchBinaryOp(U)) {
     switch (BO->Opcode) {
     case Instruction::Add: {
       // The simple thing to do would be to just call getSCEV on both operands
@@ -4918,7 +4874,7 @@ const SCEV *ScalarEvolution::createSCEV(Value *V) {
         else
           AddOps.push_back(getSCEV(BO->RHS));
 
-        auto NewBO = MatchBinaryOp(BO->LHS, DT);
+        auto NewBO = MatchBinaryOp(BO->LHS);
         if (!NewBO || (NewBO->Opcode != Instruction::Add &&
                        NewBO->Opcode != Instruction::Sub)) {
           AddOps.push_back(getSCEV(BO->LHS));
@@ -4948,7 +4904,7 @@ const SCEV *ScalarEvolution::createSCEV(Value *V) {
         }
 
         MulOps.push_back(getSCEV(BO->RHS));
-        auto NewBO = MatchBinaryOp(BO->LHS, DT);
+        auto NewBO = MatchBinaryOp(BO->LHS);
         if (!NewBO || NewBO->Opcode != Instruction::Mul) {
           MulOps.push_back(getSCEV(BO->LHS));
           break;