diff --git a/mlir/include/mlir/Dialect/Shape/IR/ShapeOps.td b/mlir/include/mlir/Dialect/Shape/IR/ShapeOps.td
--- a/mlir/include/mlir/Dialect/Shape/IR/ShapeOps.td
+++ b/mlir/include/mlir/Dialect/Shape/IR/ShapeOps.td
@@ -550,7 +550,8 @@
     - `index` is in the range [-rank(operand),rank(operand)]
   }];
 
-  let arguments = (ins Shape_ShapeOrExtentTensorType:$operand, I32:$index);
+  let arguments = (ins Shape_ShapeOrExtentTensorType:$operand,
+                       Shape_SizeOrIndexType:$index);
   let results = (outs Shape_ShapeType:$head, Shape_ShapeType:$tail);
   let hasFolder = 1;
 }
diff --git a/mlir/test/Dialect/Shape/canonicalize.mlir b/mlir/test/Dialect/Shape/canonicalize.mlir
--- a/mlir/test/Dialect/Shape/canonicalize.mlir
+++ b/mlir/test/Dialect/Shape/canonicalize.mlir
@@ -14,9 +14,9 @@
 func @f() -> (!shape.shape, !shape.shape) {
   // CHECK: shape.const_shape [2, 3] : !shape.shape
   // CHECK: shape.const_shape [4, 5] : !shape.shape
-  %c2 = constant 2 : i32
+  %c2 = constant 2 : index
   %0 = shape.const_shape [2, 3, 4, 5] : !shape.shape
-  %head, %tail = "shape.split_at"(%0, %c2) : (!shape.shape, i32) -> (!shape.shape, !shape.shape)
+  %head, %tail = "shape.split_at"(%0, %c2) : (!shape.shape, index) -> (!shape.shape, !shape.shape)
   return %head, %tail : !shape.shape, !shape.shape
 
 }
@@ -28,9 +28,9 @@
 func @f() -> (!shape.shape, !shape.shape) {
   // CHECK: shape.const_shape [2, 3, 4] : !shape.shape
   // CHECK: shape.const_shape [5] : !shape.shape
-  %c-1 = constant -1 : i32
+  %c-1 = constant -1 : index
   %0 = shape.const_shape [2, 3, 4, 5] : !shape.shape
-  %head, %tail = "shape.split_at"(%0, %c-1) : (!shape.shape, i32) -> (!shape.shape, !shape.shape)
+  %head, %tail = "shape.split_at"(%0, %c-1) : (!shape.shape, index) -> (!shape.shape, !shape.shape)
   return %head, %tail : !shape.shape, !shape.shape
 }
 
@@ -40,9 +40,9 @@
 // CHECK-LABEL: func @f
 func @f() -> (!shape.shape, !shape.shape) {
   // CHECK: shape.split_at
-  %c5 = constant 5 : i32
+  %c5 = constant 5 : index
   %0 = shape.const_shape [2, 3, 4, 5] : !shape.shape
-  %head, %tail = "shape.split_at"(%0, %c5) : (!shape.shape, i32) -> (!shape.shape, !shape.shape)
+  %head, %tail = "shape.split_at"(%0, %c5) : (!shape.shape, index) -> (!shape.shape, !shape.shape)
   return %head, %tail : !shape.shape, !shape.shape
 }