[llvm] [InlineCost] Don't call collectEphemeralValues() if too many assumptions (PR #129279)

[via llvm-commits]

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@@ -2785,7 +2791,15 @@ InlineResult CallAnalyzer::analyze() {
   // the ephemeral values multiple times (and they're completely determined by
   // the callee, so this is purely duplicate work).
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vporpo wrote:

Yes, that would be ideal. Caching the EphValues set based on the callee would probably fix the issue. The problem is that I am not sure I will be able to catch all cases where caching would need to be invalidated. I don't see any tests for this code which would make it tricky to validate.

https://github.com/llvm/llvm-project/pull/129279