[FIRRTL] Use type inference for domain anon op

Author: rwy7

include/circt/Dialect/FIRRTL/FIRRTLDeclarations.td

@@ -777,21 +777,18 @@ def ObjectOp :  FIRRTLOp<"object", [
   }];
 }
 
-def DomainCreateAnonOp : FIRRTLOp<"domain.anon", [
-    ParentOneOf<[
-      "firrtl::ContractOp",
-      "firrtl::FModuleOp",
-      "firrtl::LayerBlockOp",
-      "firrtl::MatchOp",
-      "firrtl::WhenOp",
-      "sv::IfDefOp"
-    ]>,
-    DeclareOpInterfaceMethods<SymbolUserOpInterface>
-  ]> {
+def DomainCreateAnonOp
+    : FIRRTLOp<"domain.anon",
+               [ParentOneOf<["firrtl::ContractOp", "firrtl::FModuleOp",
+                             "firrtl::LayerBlockOp", "firrtl::MatchOp",
+                             "firrtl::WhenOp", "sv::IfDefOp"]>,
+                DeclareOpInterfaceMethods<SymbolUserOpInterface>,
+                DeclareOpInterfaceMethods<InferTypeOpInterface>,
+]> {
   let summary = "Create an anonymous domain, without parameters set";
   let arguments = (ins FlatSymbolRefAttr:$domain);
   let results = (outs DomainType:$result);
-  let hasCustomAssemblyFormat = 1;
+  let assemblyFormat = [{ `of` $domain attr-dict }];
 }
 
 #endif // CIRCT_DIALECT_FIRRTL_FIRRTLDECLARATIONS_TD

lib/Dialect/FIRRTL/FIRRTLOps.cpp

@@ -7043,27 +7043,6 @@ LogicalResult BindOp::verifyInnerRefs(hw::InnerRefNamespace &ns) {
 // Domain operations
 //===----------------------------------------------------------------------===//
 
-void DomainCreateAnonOp::print(OpAsmPrinter &p) {
-  p.printOptionalAttrDict((*this)->getAttrs(), /*elidedAttrs=*/{"domain"});
-  p << " : ";
-  p.printType(getType());
-  printDomainKind(p, getDomainAttr());
-}
-
-ParseResult DomainCreateAnonOp::parse(OpAsmParser &parser,
-                                      OperationState &result) {
-  Type type;
-  FlatSymbolRefAttr domainKind;
-  if (parser.parseOptionalAttrDict(result.attributes) || parser.parseColon() ||
-      parser.parseType(type) || parseDomainKind(parser, domainKind))
-    return failure();
-
-  result.getOrAddProperties<Properties>().setDomain(domainKind);
-  result.addTypes(type);
-
-  return success();
-}
-
 LogicalResult
 DomainCreateAnonOp::verifySymbolUses(SymbolTableCollection &symbolTable) {
   auto circuitOp = getOperation()->getParentOfType<CircuitOp>();

test/Dialect/FIRRTL/emit-basic.mlir

@@ -1016,7 +1016,7 @@ firrtl.circuit "Foo" {
   // CHECK-LABEL: module AnonymousDomains :
   firrtl.module @AnonymousDomains() {
     // CHECK-NEXT: inst foo of AnonymousDomains_Foo
-    %0 = firrtl.domain.anon : !firrtl.domain of @ClockDomain
+    %0 = firrtl.domain.anon of @ClockDomain
     %foo_A = firrtl.instance foo @AnonymousDomains_Foo(
       in A: !firrtl.domain of @ClockDomain
     )

test/Dialect/FIRRTL/errors.mlir

@@ -3205,7 +3205,7 @@ firrtl.circuit "AnonDomainPointingAtNonDomain" {
   firrtl.extmodule @Foo()
   firrtl.module @UndefinedDomainInAnonDomain() {
     // expected-error @below {{references undefined domain '@Foo'}}
-    %0 = firrtl.domain.anon : !firrtl.domain of @Foo
+    %0 = firrtl.domain.anon of @Foo
   }
 }
 
@@ -3214,6 +3214,6 @@ firrtl.circuit "AnonDomainPointingAtNonDomain" {
 firrtl.circuit "UndefinedDomainInAnonDomain" {
   firrtl.module @UndefinedDomainInAnonDomain() {
     // expected-error @below {{references undefined domain '@Foo'}}
-    %0 = firrtl.domain.anon : !firrtl.domain of @Foo
+    %0 = firrtl.domain.anon of @Foo
   }
 }

test/Dialect/FIRRTL/round-trip.mlir

@@ -279,8 +279,8 @@ firrtl.module @InstanceChoiceWithDomain(in %A: !firrtl.domain of @ClockDomain, i
 // CHECK-LABEL: firrtl.module @CreateAnonDomain
 firrtl.extmodule @CreateAnonDomainChild(in A: !firrtl.domain of @ClockDomain)
 firrtl.module @CreateAnonDomain() {
-  // CHECK-NEXT: %0 = firrtl.domain.anon : !firrtl.domain of @ClockDomain
-  %0 = firrtl.domain.anon : !firrtl.domain of @ClockDomain
+  // CHECK-NEXT: %0 = firrtl.domain.anon of @ClockDomain
+  %0 = firrtl.domain.anon of @ClockDomain
   %child_A = firrtl.instance child @CreateAnonDomainChild(
     in A: !firrtl.domain of @ClockDomain
   )