[mlir][shape] Tidy up shape.shape_of

[silvas]

Summary

• Mark it NoSideEffect
• Add custom parser/printer

[jpienaar]

LG, thanks

mlir/include/mlir/Dialect/Shape/IR/ShapeOps.td

235

So this matches the style of cmpi as the result type is always known?

mlir/include/mlir/Dialect/Shape/IR/ShapeOps.td

def Shape_ReduceOp : Shape_Op<"reduce", []> {
 
   let arguments = (ins Shape_ShapeType:$shape, Variadic<AnyType>:$args);
   let results = (outs Variadic<AnyType>:$result);
 
   let regions = (region SizedRegion<1>:$body);
 }
 
 def Shape_ShapeOfOp : Shape_Op<"shape_of",
-    [DeclareOpInterfaceMethods<InferTypeOpInterface>]> {
+    [NoSideEffect, DeclareOpInterfaceMethods<InferTypeOpInterface>]> {
   let summary = "Returns shape of a value or shaped type operand";
 
   let arguments = (ins AnyTypeOf<[AnyShaped, Shape_ValueShapeType]>:$arg);
   let results = (outs Shape_ShapeType:$result);
 
+  let assemblyFormat = "attr-dict $arg `:` type($arg)";
+
   let hasFolder = 1;
 }
 
 def Shape_YieldOp : Shape_Op<"yield", [NoSideEffect, Terminator]> {
   let summary = "Returns the value to parent op";
 
   let arguments = (ins Variadic<AnyType>:$operands);
 

mlir/test/Dialect/Shape/ops.mlir

func @test_shape_any_fixed_mismatch() {
   return
 }
 
 func @test_parse_const_shape() {
   %0 = shape.const_shape []
   %1 = shape.const_shape [1, 2, 3]
   return
 }
+
+func @test_shape_of(%arg0: tensor<?xf32>) -> !shape.shape {
+  %0 = shape.shape_of %arg0 : tensor<?xf32>
+  return %0 : !shape.shape
+}