[clang] [llvm] [FunctionAttrs][Attributor] Update nofree inference (PR #196266)

[Antonio Frighetto via llvm-commits]

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@@ -297,12 +297,12 @@ define void @f2() #0 {
 
 ; TEST 12 NoFree argument - positive.
 define double @test12(ptr nocapture readonly %a) {
-; CHECK: Function Attrs: nofree nounwind
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antoniofrighetto wrote:

I'm not immediately clear why the argument-level nofree is retained here, though the function attribute is not, and how the function could cause a free through synchronization. Is this desirable? I also wonder if we should orthogonally teach BuildLibCalls to annotate cos, sin, et alia with nosync.

https://github.com/llvm/llvm-project/pull/196266