[MLIR][Shape] Add support for `OpAsmInterface` in `shape.const_size`

The SSA values created with `shape.const_size` are now named depending on the
value.
A constant size of 3, e.g., is now automatically named `%c3`.

Differential Revision: https://reviews.llvm.org/D81249

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

@@ -17,6 +17,7 @@ include "mlir/Dialect/Shape/IR/ShapeBase.td"
 include "mlir/Interfaces/ControlFlowInterfaces.td"
 include "mlir/Interfaces/InferTypeOpInterface.td"
 include "mlir/Interfaces/SideEffectInterfaces.td"
+include "mlir/IR/OpAsmInterface.td"
 
 def Shape_WitnessType : DialectType<ShapeDialect,
     CPred<"$_self.isa<::mlir::shape::WitnessType>()">, "witness">,
@@ -110,7 +111,11 @@ def Shape_ConstShapeOp : Shape_Op<"const_shape", [ConstantLike, NoSideEffect]> {
   let hasFolder = 1;
 }
 
-def Shape_ConstSizeOp : Shape_Op<"const_size", [ConstantLike, NoSideEffect]> {
+def Shape_ConstSizeOp : Shape_Op<"const_size", [
+    ConstantLike,
+    NoSideEffect,
+    DeclareOpInterfaceMethods<OpAsmOpInterface>
+  ]> {
   let summary = "Creates a constant of type `shape.size`";
   let description = [{
     Creates a `shape.size` type representing the constant size given by `value`.

mlir/lib/Dialect/Shape/IR/Shape.cpp

@@ -13,6 +13,7 @@
 #include "mlir/IR/DialectImplementation.h"
 #include "mlir/IR/PatternMatch.h"
 #include "mlir/IR/StandardTypes.h"
+#include "llvm/ADT/SmallString.h"
 #include "llvm/Support/raw_ostream.h"
 
 using namespace mlir;
@@ -352,6 +353,14 @@ OpFoldResult CstrEqOp::fold(ArrayRef<Attribute> operands) {
 
 OpFoldResult ConstSizeOp::fold(ArrayRef<Attribute>) { return valueAttr(); }
 
+void ConstSizeOp::getAsmResultNames(
+    llvm::function_ref<void(Value, StringRef)> setNameFn) {
+  SmallString<4> buffer;
+  llvm::raw_svector_ostream os(buffer);
+  os << "c" << value();
+  setNameFn(getResult(), os.str());
+}
+
 //===----------------------------------------------------------------------===//
 // ConstWitnessOp
 //===----------------------------------------------------------------------===//

mlir/test/Dialect/Shape/ops.mlir

@@ -91,3 +91,13 @@ func @test_mul(%lhs: !shape.size, %rhs: !shape.size) -> !shape.size {
   %product = shape.mul %lhs, %rhs
   return %product: !shape.size
 }
+
+func @const_size() {
+  // CHECK: %c1 = shape.const_size 1
+  // CHECK: %c2 = shape.const_size 2
+  // CHECK: %c2_0 = shape.const_size 2
+  %0 = shape.const_size 1
+  %1 = shape.const_size 2
+  %2 = shape.const_size 2
+  return
+}