Update mhlo.constant to use a custom assembly format instead of a custom printer and parser (NFC).

PiperOrigin-RevId: 325560779

include/mlir-hlo/Dialect/mhlo/IR/hlo_ops.td

@@ -67,8 +67,7 @@ def HLO_ConstOp : HLO_Op<"constant",
     "OpBuilder &builder, OperationState &result, Attribute value"
   >];
 
-  let printer = [{ return Print(*this, &p); }];
+  let assemblyFormat = "attr-dict $value";
-  let parser = [{ return ParseConstOp(&parser, &result); }];
 
   let hasFolder = 1;
 

lib/Dialect/mhlo/IR/hlo_ops.cc

@@ -112,37 +112,6 @@ DenseIntElementsAttr BuildSliceLimits(DenseIntElementsAttr start_indices,
 // ConstOp
 //===----------------------------------------------------------------------===//
 
-static void Print(ConstOp op, OpAsmPrinter* printer) {
-  // Print op name.
-  *printer << op.getOperationName();
-
-  // Elide attribute value while printing the attribute dictionary.
-  SmallVector<StringRef, 1> elided_attrs;
-  elided_attrs.push_back("value");
-  printer->printOptionalAttrDict(op.getAttrs(), elided_attrs);
-
-  *printer << ' ' << op.value();
-}
-
-static ParseResult ParseConstOp(OpAsmParser* parser, OperationState* result) {
-  if (parser->parseOptionalAttrDict(result->attributes)) return failure();
-
-  // If colon is not present after attribute dictionary, it should be short form
-  // and attribute 'value' is outside the dictionary.
-  if (failed(parser->parseOptionalColon())) {
-    Attribute value;
-    if (parser->parseAttribute(value, "value", result->attributes))
-      return failure();
-    return parser->addTypeToList(value.getType(), result->types);
-  }
-
-  // Long form should have type of the result after colon.
-  Type ty;
-  if (parser->parseType(ty)) return failure();
-  result->types.push_back(ty);
-  return success();
-}
-
 OpFoldResult ConstOp::fold(ArrayRef<Attribute> operands) {
   assert(operands.empty() && "constant has no operands");
 

tests/ops.mlir

@@ -480,7 +480,7 @@ func @map_non_scalar_computation_operand(%arg0: tensor<4x5xf32>, %arg1: tensor<4
   // expected-error@+1 {{computation arguments must be 0-rank tensor, but got: arg #1 of type 'tensor<5xf32>'}}
   %0 = "mhlo.map"(%arg0, %arg1) ( {
     ^bb0(%arg2: tensor<f32>, %arg3: tensor<5xf32>):
-    %1 = mhlo.constant {value = dense<2.0> : tensor<f32>} : tensor<f32>
+    %1 = mhlo.constant dense<2.0> : tensor<f32>
     "mhlo.return"(%1) : (tensor<f32>) -> ()
   }) {dimensions = dense<[0, 1]> : tensor<2xi64>} : (tensor<4x5xf32>, tensor<4x5xf32>) -> tensor<4x5xf32>
   return %0 : tensor<4x5xf32>
@@ -492,7 +492,7 @@ func @map_mismatch_operand_and_computation_args(%arg0: tensor<4x5xf32>, %arg1: t
   // expected-error@+1 {{element type of operands and computation arguments must match, but got: 'f32' and 'i32'}}
   %0 = "mhlo.map"(%arg0, %arg1) ( {
     ^bb0(%arg2: tensor<i32>, %arg3: tensor<i32>):
-    %1 = mhlo.constant {value = dense<2.0> : tensor<f32>} : tensor<f32>
+    %1 = mhlo.constant dense<2.0> : tensor<f32>
     "mhlo.return"(%1) : (tensor<f32>) -> ()
   }) {dimensions = dense<[0, 1]> : tensor<2xi64>} : (tensor<4x5xf32>, tensor<4x5xf32>) -> tensor<4x5xf32>
   return %0 : tensor<4x5xf32>
@@ -504,7 +504,7 @@ func @map_invalid_number_of_computation_output(%arg0: tensor<4x5xf32>, %arg1: te
   // expected-error@+1 {{computation must return single output, but got: 0}}
   %0 = "mhlo.map"(%arg0, %arg1) ( {
     ^bb0(%arg2: tensor<f32>, %arg3: tensor<f32>):
-    %1 = mhlo.constant {value = dense<2.0> : tensor<f32>} : tensor<f32>
+    %1 = mhlo.constant dense<2.0> : tensor<f32>
     "mhlo.return"() : () -> ()
   }) {dimensions = dense<[0, 1]> : tensor<2xi64>} : (tensor<4x5xf32>, tensor<4x5xf32>) -> tensor<4x5xf32>
   return %0 : tensor<4x5xf32>
@@ -516,7 +516,7 @@ func @main_non_scalar_computation_output(%arg0: tensor<4x5xf32>, %arg1: tensor<4
   // expected-error@+1 {{computation must return 0-rank tensor, but got: 'tensor<5xf32>'}}
   %0 = "mhlo.map"(%arg0, %arg1) ( {
     ^bb0(%arg2: tensor<f32>, %arg3: tensor<f32>):
-    %1 = mhlo.constant {value = dense<2.0> : tensor<f32>} : tensor<5xf32>
+    %1 = mhlo.constant dense<2.0> : tensor<5xf32>
     "mhlo.return"(%1) : (tensor<5xf32>) -> ()
   }) {dimensions = dense<[0, 1]> : tensor<2xi64>} : (tensor<4x5xf32>, tensor<4x5xf32>) -> tensor<4x5xf32>
   return %0 : tensor<4x5xf32>
@@ -528,7 +528,7 @@ func @mismatch_computation_output_type(%arg0: tensor<4x5xf32>, %arg1: tensor<4x5
   // expected-error@+1 {{element type of result and computation output must match, but got: 'f32' and 'i32'}}
   %0 = "mhlo.map"(%arg0, %arg1) ( {
     ^bb0(%arg2: tensor<f32>, %arg3: tensor<f32>):
-    %1 = mhlo.constant {value = dense<2> : tensor<i32>} : tensor<i32>
+    %1 = mhlo.constant dense<2> : tensor<i32>
     "mhlo.return"(%1) : (tensor<i32>) -> ()
   }) {dimensions = dense<[0, 1]> : tensor<2xi64>} : (tensor<4x5xf32>, tensor<4x5xf32>) -> tensor<4x5xf32>
   return %0 : tensor<4x5xf32>