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

[via llvm-commits]

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@@ -4378,7 +4378,8 @@ void CodeGenDAGPatterns::ParsePatterns() {
       FindPatternInputsAndOutputs(Pattern, Pattern.getTree(j), InstInputs,
                                   InstResults, InstImpResults);
 
-    ParseOnePattern(CurPattern, Pattern, Result, InstImpResults);
+    ParseOnePattern(CurPattern, Pattern, Result, InstImpResults,
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jofrn wrote:

Trying to name it after its functionality, not necessarily its usage. We originally thought it to disable imports in the SelectionDAG, but it disables the imports from the perspective of GISel; so calling it with a GI prefix makes sense, but it has more general usage than that.

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