revert 278334

llvm-svn: 278337

1 files changed, 0 insertions, 27 deletions

diff --git a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
index ddd5cdc6bcc..056886f80e6 100644
--- a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -1989,34 +1989,7 @@ linearFunctionTestReplace(Loop *L,
 
       DEBUG(dbgs() << "  Widen RHS:\t" << *ExitCnt << "\n");
     } else {
-      // We try to extend trip count first. If that doesn't work we truncate IV.
-      // Zext(trunc(IV)) == IV implies equivalence of the following two:
-      // Trunc(IV) == ExitCnt and IV == zext(ExitCnt). Similarly for sext. If
-      // one of the two holds, extend the trip count, otherwise truncate IV.
-      bool Extended = false;
-      const SCEV *IV = SE->getSCEV(CmpIndVar);
-      const SCEV *ZExtTrunc =
-           SE->getZeroExtendExpr(SE->getTruncateExpr(SE->getSCEV(CmpIndVar),
-                                                     ExitCnt->getType()),
-                                 CmpIndVar->getType());
-
-      if (ZExtTrunc == IV) {
-        Extended = true;
-        ExitCnt = Builder.CreateZExt(ExitCnt, IndVar->getType(),
-                                     "wide.trip.count");
-      } else {
-        const SCEV *SExtTrunc =
-          SE->getSignExtendExpr(SE->getTruncateExpr(SE->getSCEV(CmpIndVar),
-                                                    ExitCnt->getType()),
-                                CmpIndVar->getType());
-        if (SExtTrunc == IV) {
-          Extended = true;
-          ExitCnt = Builder.CreateSExt(ExitCnt, IndVar->getType(),
-                                       "wide.trip.count");
-        }
-      }
 
-      if (!Extended)
         CmpIndVar = Builder.CreateTrunc(CmpIndVar, ExitCnt->getType(),
                                         "lftr.wideiv");
     }