[llvm] [TableGen] Add `!instances` operator to get defined records (PR #129680)

[Pengcheng Wang via llvm-commits]

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@@ -0,0 +1,60 @@
+// RUN: llvm-tblgen %s | FileCheck %s
+// RUN: not llvm-tblgen -DERROR1 %s 2>&1 | FileCheck --check-prefix=ERROR1 %s
+// RUN: not llvm-tblgen -DERROR2 %s 2>&1 | FileCheck --check-prefix=ERROR2 %s
+// RUN: not llvm-tblgen -DERROR3 %s 2>&1 | FileCheck --check-prefix=ERROR3 %s
+// XFAIL: vg_leak
+
+class A;
+def a0 : A;
+def a1 : A;
+
+class B : A;
+def b0 : B;
+def b1 : B;
+
+def instances_A {
+  list<A> instances = !instances<A>();
+}
+
+def instances_A_x0 {
+  list<A> instances = !instances<A>(".*0");
+}
+
+def instances_A_x1 {
+  list<A> instances = !instances<A>(".*1");
+}
+
+def instances_B {
+  list<B> instances = !instances<B>();
+}
+
+// CHECK-LABEL: def instances_A {
+// CHECK-NEXT:    list<A> instances = [a0, a1, b0, b1];
+// CHECK-NEXT:  }
+
+// CHECK-LABEL: def instances_A_x0 {
+// CHECK-NEXT:    list<A> instances = [a0, b0];
+// CHECK-NEXT:  }
+
+// CHECK-LABEL: def instances_A_x1 {
+// CHECK-NEXT:    list<A> instances = [a1, b1];
+// CHECK-NEXT:  }
+
+// CHECK-LABEL: def instances_B {
+// CHECK-NEXT:    list<B> instances = [b0, b1];
+// CHECK-NEXT:  }
+
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wangpc-pp wrote:

The answer is a3 will not be included.

https://github.com/llvm/llvm-project/pull/129680