[llvm] [FunctionAttrs] Treat byval calls as only reading ptrs (PR #122618)

[Nikita Popov via llvm-commits]

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@@ -16,14 +16,10 @@ declare void @llvm.memcpy.p0.p0.i64(ptr noalias nocapture writeonly, ptr noalias
 define i1 @alloca_forwarding_lifetime_end_clobber() {
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nikic wrote:

Should update the comment above here, because we now do the optimization by dropping the lifetime intrinsics.

https://github.com/llvm/llvm-project/pull/122618