[llvm] [PowerPC] Add flag to DAG combiner to improve compile time. (PR #86884)

[Matt Arsenault via llvm-commits]

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@@ -150,6 +150,11 @@ static cl::opt<bool> EnableVectorFCopySignExtendRound(
     cl::desc(
         "Enable merging extends and rounds into FCOPYSIGN on vector types"));
 
+static cl::opt<bool>
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arsenm wrote:

These flags aren't really intended for end users, and are difficult to discover. Is there a threshold or something you can add instead?

https://github.com/llvm/llvm-project/pull/86884