[Mlir-commits] [mlir] [mlir] Add concept of alias blocks (PR #65503)

[Jeff Niu]

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@@ -880,3 +882,26 @@ version using readAttribute and readType methods.
 There is no restriction on what kind of information a dialect is allowed to
 encode to model its versioning. Currently, versioning is supported only for
 bytecode formats.
+
+## Alias Block Definitions
+
+An alias block is a list of subsequent attribute or type alias definitions that
+are conceptually parsed as one unit.
+This allows any alias definition within the block to reference any other alias 
+definition within the block, regardless if defined lexically later or earlier in
+the block.
+
+```mlir
+// Alias block consisting of #array, !integer_type and #integer_attr.
+#array = [#integer_attr, !integer_type]
----------------
Mogball wrote:

If understand this correctly, it's basically a forward declaration?

https://github.com/llvm/llvm-project/pull/65503