diff --git a/llvm/lib/IR/Instructions.cpp b/llvm/lib/IR/Instructions.cpp
--- a/llvm/lib/IR/Instructions.cpp
+++ b/llvm/lib/IR/Instructions.cpp
@@ -81,7 +81,7 @@
     VectorType *ET = dyn_cast<VectorType>(Op1->getType());
     if (!ET)
       return "selected values for vector select must be vectors";
-    if (ET->getNumElements() != VT->getNumElements())
+    if (ET->getElementCount() != VT->getElementCount())
       return "vector select requires selected vectors to have "
                    "the same vector length as select condition";
   } else if (Op0->getType() != Type::getInt1Ty(Op0->getContext())) {
diff --git a/llvm/test/CodeGen/AArch64/sve-bad-select.ll b/llvm/test/CodeGen/AArch64/sve-bad-select.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/AArch64/sve-bad-select.ll
@@ -0,0 +1,10 @@
+; RUN: not llc -mtriple=aarch64-linux-gnu -mattr=+sve < %s 2>&1 | FileCheck %s
+
+define <vscale x 16 x i8> @badsel1_nxv16i8(<16 x i1> %p,
+                                           <vscale x 16 x i8> %dst,
+                                           <vscale x 16 x i8> %a) {
+  %sel = select <16 x i1> %p, <vscale x 16 x i8> %a, <vscale x 16 x i8> %dst
+  ret <vscale x 16 x i8> %sel
+}
+
+; CHECK: error: vector select requires selected vectors to have the same vector length as select condition