[llvm] [ConstantFolding] Implement canConstantFoldCallTo() using TLI (PR #221903)

[Nikita Popov via llvm-commits]

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nikic wrote:

Both cases should not pass TLI to canConstantFoldCallTo(), because they don't pass TLI to ConstantFoldCall():
https://github.com/llvm/llvm-project/blob/5886c703eb2d205656811d78db82b76524c47da9/llvm/lib/Transforms/IPO/FunctionSpecialization.cpp#L426
https://github.com/llvm/llvm-project/blob/5886c703eb2d205656811d78db82b76524c47da9/llvm/lib/Analysis/InlineCost.cpp#L2429

> Is it possible then to make TLI non-optional, so callers don't forget to pass it?

I think in that case we'd want it to be non-optional on both functions, not just one of them.

https://github.com/llvm/llvm-project/pull/221903