[PATCH] D67286: [Attributor] Implement "noalias" callsite argument deduction

[Hideto Ueno via Phabricator via llvm-commits]

uenoku added inline comments.


================
Comment at: llvm/test/Transforms/FunctionAttrs/noalias_returned.ll:235
+  ret void
+}
----------------
jdoerfert wrote:
> We need to make sure this test works as well:
> 
> ```
> define void @test12_3(){
>   %A = tail call noalias i8* @malloc(i64 4)
>   tail call void @two_args(i8* %A, i8* %A)
>   ret void
> }
> ```
If @two_args is:
```
declare void @two_args(i8* nocapture , i8* nocapture)
```
then
```
define void @test12_3(){
  %A = tail call noalias i8* @malloc(i64 4)
  tail call void @two_args(i8* noalias nocapture %A, i8* noalias nocapture%A)
  ret void
}
```
(If either argument is not marked as `nocapture`, there is no problem.)
It is not good ... I'll fix. We need to compare the call site argument and ensure that there is no copy.




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  https://reviews.llvm.org/D67286/new/

https://reviews.llvm.org/D67286