diff --git a/polly/include/polly/CodeGen/BlockGenerators.h b/polly/include/polly/CodeGen/BlockGenerators.h
index 0e6d0cbdcdb1..d8f21d53d9a3 100644
--- a/polly/include/polly/CodeGen/BlockGenerators.h
+++ b/polly/include/polly/CodeGen/BlockGenerators.h
@@ -103,10 +103,11 @@ protected:
   /// @brief Get the new version of a value.
   ///
   /// Given an old value, we first check if a new version of this value is
-  /// available in the BBMap or GlobalMap. If the value is scop constant, we
-  /// assume it is a parameter and return the old value. In case it is not and
-  /// the value can be recomputed using SCEV, we do so. If the value can still
-  /// not be derived, this function will assert.
+  /// available in the BBMap or GlobalMap. In case it is not and the value can
+  /// be recomputed using SCEV, we do so. If we can not recompute a value
+  /// using SCEV, but we understand that the value is constant within the scop,
+  /// we return the old value.  If the value can still not be derived, this
+  /// function will assert.
   ///
   /// @param Old       The old Value.
   /// @param BBMap     A mapping from old values to their new values
diff --git a/polly/lib/CodeGen/BlockGenerators.cpp b/polly/lib/CodeGen/BlockGenerators.cpp
index 8d1734c39485..8788151dccea 100644
--- a/polly/lib/CodeGen/BlockGenerators.cpp
+++ b/polly/lib/CodeGen/BlockGenerators.cpp
@@ -88,15 +88,6 @@ Value *BlockGenerator::getNewValue(const Value *Old, ValueMapT &BBMap,
     return New;
   }
 
-  // Or it is probably a scop-constant value defined as global, function
-  // parameter or an instruction not within the scop.
-  if (isa<GlobalValue>(Old) || isa<Argument>(Old))
-    return const_cast<Value *>(Old);
-
-  if (const Instruction *Inst = dyn_cast<Instruction>(Old))
-    if (!Statement.getParent()->getRegion().contains(Inst->getParent()))
-      return const_cast<Value *>(Old);
-
   if (Value *New = BBMap.lookup(Old))
     return New;
 
@@ -117,8 +108,16 @@ Value *BlockGenerator::getNewValue(const Value *Old, ValueMapT &BBMap,
       }
     }
 
-  // Now the scalar dependence is neither available nor SCEVCodegenable, this
-  // should never happen in the current code generator.
+  // A scop-constant value defined by a global or a function parameter.
+  if (isa<GlobalValue>(Old) || isa<Argument>(Old))
+    return const_cast<Value *>(Old);
+
+  // A scop-constant value defined by an instruction executed outside the scop.
+  if (const Instruction *Inst = dyn_cast<Instruction>(Old))
+    if (!Statement.getParent()->getRegion().contains(Inst->getParent()))
+      return const_cast<Value *>(Old);
+
+  // The scalar dependence is neither available nor SCEVCodegenable.
   llvm_unreachable("Unexpected scalar dependence in region!");
   return nullptr;
 }
diff --git a/polly/test/Isl/CodeGen/scalar-references-used-in-scop-compute.ll b/polly/test/Isl/CodeGen/scalar-references-used-in-scop-compute.ll
new file mode 100644
index 000000000000..3ab7529c03f7
--- /dev/null
+++ b/polly/test/Isl/CodeGen/scalar-references-used-in-scop-compute.ll
@@ -0,0 +1,51 @@
+; RUN: opt %loadPolly -polly-codegen-isl -S -polly-codegen-scev < %s | FileCheck %s
+
+; Test the code generation in the presence of a scalar out-of-scop value being
+; used from within the SCoP.
+
+; CHECH-LABEL: @scalar-function-argument
+; CHECK: polly.split_new_and_old
+
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define void @scalar-function-argument(float* %A, float %sqrinv) {
+entry:
+  br label %for.body
+
+for.body:
+  %indvar = phi i64 [ %indvar.next, %for.body ], [ 0, %entry ]
+  %mul104 = fmul float 1.0, %sqrinv
+  %rp107 = getelementptr float* %A, i64 %indvar
+  store float %mul104, float* %rp107, align 4
+  %indvar.next = add nsw i64 %indvar, 1
+  %cmp = icmp slt i64 1024, %indvar.next
+  br i1 %cmp, label %for.end, label %for.body
+
+for.end:
+  ret void
+}
+
+; CHECH-LABEL: @scalar-outside-of-scop
+; CHECK: polly.split_new_and_old
+
+define void @scalar-outside-of-scop(float* %A) {
+entry:
+  %sqrinv = call float @getFloat()
+  br label %for.body
+
+for.body:
+  %indvar = phi i64 [ %indvar.next, %for.body ], [ 0, %entry ]
+  %mul104 = fmul float 1.0, %sqrinv
+  %rp107 = getelementptr float* %A, i64 %indvar
+  store float %mul104, float* %rp107, align 4
+  %indvar.next = add nsw i64 %indvar, 1
+  %cmp = icmp slt i64 1024, %indvar.next
+  br i1 %cmp, label %for.end, label %for.body
+
+for.end:
+  ret void
+}
+
+declare float @getFloat()