[llvm] Attributor: Add denormal-fp-math to attributor-light (PR #79576)

[Shilei Tian via llvm-commits]

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@@ -371,7 +371,6 @@ define void @nc4(ptr %p) {
 ; ATTRIBUTOR: Function Attrs: nosync nounwind memory(read)
 ; ATTRIBUTOR-LABEL: define void @nc4
 ; ATTRIBUTOR-SAME: (ptr nocapture readonly [[P:%.*]]) #[[ATTR7:[0-9]+]] {
-; ATTRIBUTOR-NEXT:    call void @external(ptr nocapture readonly [[P]]) #[[ATTR4]]
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shiltian wrote:

No, AA works in a way that, it assumes all uses are dead at the beginning and then makes uses alive from iteration to iteration. 

https://github.com/llvm/llvm-project/pull/79576