diff --git a/mlir/lib/Conversion/StandardToLLVM/StandardToLLVM.cpp b/mlir/lib/Conversion/StandardToLLVM/StandardToLLVM.cpp
--- a/mlir/lib/Conversion/StandardToLLVM/StandardToLLVM.cpp
+++ b/mlir/lib/Conversion/StandardToLLVM/StandardToLLVM.cpp
@@ -2184,7 +2184,7 @@
         [&](LLVM::LLVMType llvmVectorTy, ValueRange operands) {
           auto splatAttr = SplatElementsAttr::get(
               mlir::VectorType::get(
-                  {cast<llvm::VectorType>(llvmVectorTy.getUnderlyingType())
+                  {cast<llvm::FixedVectorType>(llvmVectorTy.getUnderlyingType())
                        ->getNumElements()},
                   floatType),
               floatOne);
diff --git a/mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp b/mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp
--- a/mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp
+++ b/mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp
@@ -104,8 +104,9 @@
     return parser.emitError(trailingTypeLoc, "expected LLVM IR dialect type");
   if (argType.getUnderlyingType()->isVectorTy())
     resultType = LLVMType::getVectorTy(
-        resultType, llvm::cast<llvm::VectorType>(argType.getUnderlyingType())
-                        ->getNumElements());
+        resultType,
+        llvm::cast<llvm::FixedVectorType>(argType.getUnderlyingType())
+            ->getNumElements());
 
   result.addTypes({resultType});
   return success();
@@ -1815,7 +1816,8 @@
       llvm::cast<llvm::VectorType>(getUnderlyingType())->getElementType());
 }
 unsigned LLVMType::getVectorNumElements() {
-  return llvm::cast<llvm::VectorType>(getUnderlyingType())->getNumElements();
+  return llvm::cast<llvm::FixedVectorType>(getUnderlyingType())
+      ->getNumElements();
 }
 bool LLVMType::isVectorTy() { return getUnderlyingType()->isVectorTy(); }
 
diff --git a/mlir/lib/Target/LLVMIR/ModuleTranslation.cpp b/mlir/lib/Target/LLVMIR/ModuleTranslation.cpp
--- a/mlir/lib/Target/LLVMIR/ModuleTranslation.cpp
+++ b/mlir/lib/Target/LLVMIR/ModuleTranslation.cpp
@@ -121,7 +121,7 @@
       elementType = arrayTy->getElementType();
       numElements = arrayTy->getNumElements();
     } else {
-      auto *vectorTy = cast<llvm::VectorType>(llvmType);
+      auto *vectorTy = cast<llvm::FixedVectorType>(llvmType);
       elementType = vectorTy->getElementType();
       numElements = vectorTy->getNumElements();
     }