Index: mlir/lib/IR/BuiltinAttributes.cpp
===================================================================
--- mlir/lib/IR/BuiltinAttributes.cpp
+++ mlir/lib/IR/BuiltinAttributes.cpp
@@ -1188,8 +1188,11 @@
   size_t elementBitWidth = getDenseElementStorageWidth(elementType);
   assert(numElements * elementBitWidth == inRawData.size() * CHAR_BIT &&
          inRawData.size() <= outRawData.size());
-  convertEndianOfCharForBEmachine(inRawData.begin(), outRawData.begin(),
-                                  elementBitWidth, numElements);
+  if (elementBitWidth <= CHAR_BIT)
+    std::memcpy(outRawData.begin(), inRawData.begin(), inRawData.size());
+  else
+    convertEndianOfCharForBEmachine(inRawData.begin(), outRawData.begin(),
+                                    elementBitWidth, numElements);
 }
 
 //===----------------------------------------------------------------------===//
Index: mlir/test/IR/parse-literal.mlir
===================================================================
--- /dev/null
+++ mlir/test/IR/parse-literal.mlir
@@ -0,0 +1,43 @@
+// RUN: mlir-opt %s | FileCheck %s
+
+// CHECK-LABEL: @parse_i64_tensor
+func.func @parse_i64_tensor() -> tensor<4xi64> {
+  // CHECK: dense<255> : tensor<4xi64>
+  %0 = arith.constant dense<"0xFF00000000000000FF00000000000000FF00000000000000FF00000000000000"> : tensor<4xi64>
+  return %0 : tensor<4xi64>
+}
+
+// CHECK-LABEL: @parse_i32_tensor
+func.func @parse_i32_tensor() -> tensor<8xi32> {
+  // CHECK: dense<255> : tensor<8xi32>
+  %0 = arith.constant dense<"0xFF000000FF000000FF000000FF000000FF000000FF000000FF000000FF000000"> : tensor<8xi32>
+  return %0 : tensor<8xi32>
+}
+
+// CHECK-LABEL: @parse_i16_tensor
+func.func @parse_i16_tensor() -> tensor<16xi16> {
+  // CHECK: dense<255> : tensor<16xi16>
+  %0 = arith.constant dense<"0xFF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00"> : tensor<16xi16>
+  return %0 : tensor<16xi16>
+}
+
+// CHECK-LABEL: @parse_i8_tensor
+func.func @parse_i8_tensor() -> tensor<32xi8> {
+  // CHECK: dense<15> : tensor<32xi8>
+  %0 = arith.constant dense<"0x0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F"> : tensor<32xi8>
+  return %0 : tensor<32xi8>
+}
+
+// CHECK-LABEL: @parse_i4_tensor
+func.func @parse_i4_tensor() -> tensor<32xi4> {
+  // CHECK: dense<-1> : tensor<32xi4>
+  %0 = arith.constant dense<"0x0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F"> : tensor<32xi4>
+  return %0 : tensor<32xi4>
+}
+
+// CHECK-LABEL: @parse_i1_tensor
+func.func @parse_i1_tensor() -> tensor<256xi1> {
+  // CHECK: dense<"0x0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F"> : tensor<256xi1>
+  %0 = arith.constant dense<"0x0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F"> : tensor<256xi1>
+  return %0 : tensor<256xi1>
+}