[mlir][Complex] Change complex.number attribute type to ComplexType.

[akuegel]

Summary

It is more useful to use ComplexType as type of the attribute than to
use the element type as attribute type. This means when using this
attribute in complex::ConstantOp, we just need to check whether
the types match.

[pifon2a]

Thank you, Adrian!

mlir/lib/Dialect/Complex/IR/ComplexDialect.cpp

 
 #define GET_ATTRDEF_CLASSES
 #include "mlir/Dialect/Complex/IR/ComplexAttributes.cpp.inc"
 
 LogicalResult complex::NumberAttr::verify(
     ::llvm::function_ref<::mlir::InFlightDiagnostic()> emitError,
     ::llvm::APFloat real, ::llvm::APFloat imag, ::mlir::Type type) {
 
-  if (!type.isa<FloatType>())
+  if (!type.isa<ComplexType>())
+    return emitError() << "complex attribute must be a complex type.";
+
+  Type elementType = type.cast<ComplexType>().getElementType();
+  if (!elementType.isa<FloatType>())
     return emitError()
-           << "element of the complex attribute must be float like type.";
+           << "element type of the complex attribute must be float like type.";
 
-  const auto &typeFloatSemantics = type.cast<FloatType>().getFloatSemantics();
+  const auto &typeFloatSemantics =
+      elementType.cast<FloatType>().getFloatSemantics();
   if (&real.getSemantics() != &typeFloatSemantics)
     return emitError()
            << "type doesn't match the type implied by its `real` value";
   if (&imag.getSemantics() != &typeFloatSemantics)
     return emitError()
            << "type doesn't match the type implied by its `imag` value";
 
   return success();
 }
 
 void complex::NumberAttr::print(AsmPrinter &printer) const {
-  printer << "<:" << getType() << " " << getReal() << ", " << getImag() << ">";
+  printer << "<:" << getType().cast<ComplexType>().getElementType() << " "
+          << getReal() << ", " << getImag() << ">";
 }
 
 Attribute complex::NumberAttr::parse(AsmParser &parser, Type odsType) {
   Type type;
   double real, imag;
   if (parser.parseLess() || parser.parseColon() || parser.parseType(type) ||
       parser.parseFloat(real) || parser.parseComma() ||
       parser.parseFloat(imag) || parser.parseGreater())
     return {};
 
   bool unused = false;
   APFloat realFloat(real);
   realFloat.convert(type.cast<FloatType>().getFloatSemantics(),
                     APFloat::rmNearestTiesToEven, &unused);
   APFloat imagFloat(imag);
   imagFloat.convert(type.cast<FloatType>().getFloatSemantics(),
                     APFloat::rmNearestTiesToEven, &unused);
-  return NumberAttr::get(parser.getContext(), realFloat, imagFloat, type);
+  return NumberAttr::get(parser.getContext(), realFloat, imagFloat,
+                         ComplexType::get(type));
 }

mlir/test/Dialect/Complex/attribute.mlir

 // RUN: mlir-opt %s -split-input-file -allow-unregistered-dialect -verify-diagnostics | FileCheck %s
 
 func.func @number_attr_f64() {
   "test.number_attr"() {
-    // CHECK: attr = #complex.number<:f64 1.000000e+00, 0.000000e+00> : f64
+    // CHECK: attr = #complex.number<:f64 1.000000e+00, 0.000000e+00> : complex<f64>
     attr = #complex.number<:f64 1.0, 0.0>
   } : () -> ()
 
   return
 }
 
 func.func @number_attr_f32() {
   "test.number_attr"() {
-    // CHECK: attr = #complex.number<:f32 1.000000e+00, 0.000000e+00> : f32
+    // CHECK: attr = #complex.number<:f32 1.000000e+00, 0.000000e+00> : complex<f32>
     attr = #complex.number<:f32 1.0, 0.0>
   } : () -> ()
 
   return
 }