[mlir] Promote the SubElementInterfaces to a core Attribute/Type construct

This commit restructures the sub element infrastructure to be a core part
of attributes and types, instead of being relegated to an interface. This
establishes sub element walking/replacement as something "always there",
which makes it easier to rely on for correctness/etc (which various bits of
infrastructure want, such as Symbols).

Attribute/Type now have `walk` and `replace` methods directly
accessible, which provide power API for interacting with sub elements. As
part of this, a new AttrTypeWalker class is introduced that supports caching
walked attributes/types, and a friendlier API (see the simplification of symbol
walking in SymbolTable.cpp).

Differential Revision: https://reviews.llvm.org/D142272

1 files changed, 8 insertions, 6 deletions

diff --git a/mlir/lib/IR/ExtensibleDialect.cpp b/mlir/lib/IR/ExtensibleDialect.cpp
index 701683fdcb5c..00849857b51d 100644
--- a/mlir/lib/IR/ExtensibleDialect.cpp
+++ b/mlir/lib/IR/ExtensibleDialect.cpp
@@ -407,9 +407,10 @@ void ExtensibleDialect::registerDynamicType(
   assert(registered &&
          "Trying to create a new dynamic type with an existing name");
 
-  auto abstractType =
-      AbstractType::get(*dialect, DynamicAttr::getInterfaceMap(),
-                        DynamicType::getHasTraitFn(), typeID);
+  auto abstractType = AbstractType::get(
+      *dialect, DynamicAttr::getInterfaceMap(), DynamicType::getHasTraitFn(),
+      DynamicType::getWalkImmediateSubElementsFn(),
+      DynamicType::getReplaceImmediateSubElementsFn(), typeID);
 
   /// Add the type to the dialect and the type uniquer.
   addType(typeID, std::move(abstractType));
@@ -436,9 +437,10 @@ void ExtensibleDialect::registerDynamicAttr(
   assert(registered &&
          "Trying to create a new dynamic attribute with an existing name");
 
-  auto abstractAttr =
-      AbstractAttribute::get(*dialect, DynamicAttr::getInterfaceMap(),
-                             DynamicAttr::getHasTraitFn(), typeID);
+  auto abstractAttr = AbstractAttribute::get(
+      *dialect, DynamicAttr::getInterfaceMap(), DynamicAttr::getHasTraitFn(),
+      DynamicAttr::getWalkImmediateSubElementsFn(),
+      DynamicAttr::getReplaceImmediateSubElementsFn(), typeID);
 
   /// Add the type to the dialect and the type uniquer.
   addAttribute(typeID, std::move(abstractAttr));