Index: llvm/lib/IR/Function.cpp
===================================================================
--- llvm/lib/IR/Function.cpp
+++ llvm/lib/IR/Function.cpp
@@ -1180,7 +1180,7 @@
     case IITDescriptor::Quad: return !Ty->isFP128Ty();
     case IITDescriptor::Integer: return !Ty->isIntegerTy(D.Integer_Width);
     case IITDescriptor::Vector: {
-      VectorType *VT = dyn_cast<VectorType>(Ty);
+      FixedVectorType *VT = dyn_cast<FixedVectorType>(Ty);
       return !VT || VT->getNumElements() != D.Vector_Width ||
              matchIntrinsicType(VT->getElementType(), Infos, ArgTys,
                                 DeferredChecks, IsDeferredCheck);
@@ -1357,7 +1357,11 @@
     case IITDescriptor::ScalableVecArgument: {
       if (!isa<ScalableVectorType>(Ty))
         return true;
-      return matchIntrinsicType(Ty, Infos, ArgTys, DeferredChecks,
+      ScalableVectorType *STy = cast<ScalableVectorType>(Ty);
+      unsigned MinElts = STy->getMinNumElements();
+      FixedVectorType *FVTy =
+          FixedVectorType::get(STy->getElementType(), MinElts);
+      return matchIntrinsicType(FVTy, Infos, ArgTys, DeferredChecks,
                                 IsDeferredCheck);
     }
     case IITDescriptor::VecOfBitcastsToInt: {
Index: llvm/test/CodeGen/AArch64/sve-bad-intrinsics.ll
===================================================================
--- /dev/null
+++ llvm/test/CodeGen/AArch64/sve-bad-intrinsics.ll
@@ -0,0 +1,13 @@
+; RUN: not llc -mtriple=aarch64-linux-gnu -mattr=+sve < %s 2>%t
+; RUN: FileCheck --check-prefix=CHECK-ERROR %s <%t
+
+; CHECK-ERROR: error: invalid forward reference to function 'llvm.aarch64.sve.add.nxv2i64' with wrong type
+
+define <2 x i64> @add_i64_invalid(<2 x i1> %pg, <2 x i64> %a, <2 x i64> %b) {
+  %out = call <2 x i64> @llvm.aarch64.sve.add.nxv2i64(<2 x i1> %pg,
+                                                      <2 x i64> %a,
+                                                      <2 x i64> %b)
+  ret <2 x i64> %out
+}
+
+declare <vscale x  2 x i64> @llvm.aarch64.sve.add.nxv2i64(<vscale x  2 x i1>, <vscale x  2 x i64>, <vscale x  2 x i64>)