Index: llvm/trunk/lib/Analysis/ScalarEvolution.cpp
===================================================================
--- llvm/trunk/lib/Analysis/ScalarEvolution.cpp
+++ llvm/trunk/lib/Analysis/ScalarEvolution.cpp
@@ -205,11 +205,6 @@
                   cl::desc("Max coefficients in AddRec during evolving"),
                   cl::init(16));
 
-static cl::opt<bool> VersionUnknown(
-    "scev-version-unknown", cl::Hidden,
-    cl::desc("Use predicated scalar evolution to version SCEVUnknowns"),
-    cl::init(false));
-
 //===----------------------------------------------------------------------===//
 //                           SCEV class definitions
 //===----------------------------------------------------------------------===//
@@ -11644,8 +11639,6 @@
   // couldn't create an AddRec for it, or couldn't add the predicate), we just
   // return \p Expr.
   const SCEV *convertToAddRecWithPreds(const SCEVUnknown *Expr) {
-    if (!VersionUnknown)
-      return Expr;
     if (!isa<PHINode>(Expr->getValue()))
       return Expr;
     Optional<std::pair<const SCEV *, SmallVector<const SCEVPredicate *, 3>>>
Index: llvm/trunk/test/Transforms/LoopVectorize/X86/pr36524.ll
===================================================================
--- llvm/trunk/test/Transforms/LoopVectorize/X86/pr36524.ll
+++ llvm/trunk/test/Transforms/LoopVectorize/X86/pr36524.ll
@@ -1,4 +1,4 @@
-; RUN: opt -S -scev-version-unknown -loop-vectorize -force-vector-width=4 -force-vector-interleave=1 < %s | FileCheck %s
+; RUN: opt -S -loop-vectorize -force-vector-width=4 -force-vector-interleave=1 < %s | FileCheck %s
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128-ni:1"
 
Index: llvm/trunk/test/Transforms/LoopVectorize/pr30654-phiscev-sext-trunc.ll
===================================================================
--- llvm/trunk/test/Transforms/LoopVectorize/pr30654-phiscev-sext-trunc.ll
+++ llvm/trunk/test/Transforms/LoopVectorize/pr30654-phiscev-sext-trunc.ll
@@ -1,4 +1,4 @@
-; RUN: opt -S -loop-vectorize -force-vector-width=4 -force-vector-interleave=1 -scev-version-unknown < %s 2>&1 | FileCheck %s
+; RUN: opt -S -loop-vectorize -force-vector-width=4 -force-vector-interleave=1 < %s 2>&1 | FileCheck %s
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 
Index: llvm/trunk/test/Transforms/LoopVectorize/pr35773.ll
===================================================================
--- llvm/trunk/test/Transforms/LoopVectorize/pr35773.ll
+++ llvm/trunk/test/Transforms/LoopVectorize/pr35773.ll
@@ -1,4 +1,4 @@
-; RUN: opt -S -loop-vectorize -force-vector-width=4 -force-vector-interleave=1 -scev-version-unknown < %s 2>&1 | FileCheck %s
+; RUN: opt -S -loop-vectorize -force-vector-width=4 -force-vector-interleave=1 < %s 2>&1 | FileCheck %s
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 @a = common local_unnamed_addr global i32 0, align 4
 @b = common local_unnamed_addr global i8 0, align 1
Index: llvm/trunk/test/Transforms/LoopVectorize/vect-phiscev-sext-trunc.ll
===================================================================
--- llvm/trunk/test/Transforms/LoopVectorize/vect-phiscev-sext-trunc.ll
+++ llvm/trunk/test/Transforms/LoopVectorize/vect-phiscev-sext-trunc.ll
@@ -1,5 +1,5 @@
-; RUN: opt -S -loop-vectorize -force-vector-width=8 -force-vector-interleave=1 -scev-version-unknown < %s | FileCheck %s -check-prefix=VF8
-; RUN: opt -S -loop-vectorize -force-vector-width=1 -force-vector-interleave=4 -scev-version-unknown < %s | FileCheck %s -check-prefix=VF1
+; RUN: opt -S -loop-vectorize -force-vector-width=8 -force-vector-interleave=1 < %s | FileCheck %s -check-prefix=VF8
+; RUN: opt -S -loop-vectorize -force-vector-width=1 -force-vector-interleave=4 < %s | FileCheck %s -check-prefix=VF1
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"