[llvm] [TableGen] Add a !listflatten operator to TableGen (PR #109346)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,6 @@
+// RUN: not llvm-tblgen %s 2>&1 | FileCheck %s  -DFILE=%s
+
+// CHECK: [[FILE]]:[[@LINE+2]]:33: error: expected argument of type list of list in !listflatten operator
+class Flatten<list<int> A> {
+    list<int> F = !listflatten(A);
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arsenm wrote:

Test with some non-list types too. For the case of an already flat list, should it really be an error or a no-op? 

https://github.com/llvm/llvm-project/pull/109346