[llvm] [TableGen] New tblgen Pattern bit to disable GISel pattern imports (PR #88382)

[Matt Arsenault via llvm-commits]

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@@ -1,4 +1,5 @@
 // RUN: llvm-tblgen -gen-global-isel -I %p/../../include -I %p/Common %s -o - | FileCheck %s
+// RUN: llvm-tblgen -gen-global-isel -I %p/../../include -I %p/Common %s -o - -DIGNORE | FileCheck %s --check-prefix=CHECK0
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arsenm wrote:

The entire point of the feature is to silence the warning for cases we don't want to import though 

https://github.com/llvm/llvm-project/pull/88382