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

[Johannes Doerfert via Phabricator via llvm-commits]

jdoerfert added a comment.

Except the nocapture changes this looks good to me. Can we make sure these are needed before we commit this?



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Comment at: llvm/lib/Transforms/IPO/Attributor.cpp:1732
+    //      FIXME: This is conservative though, it is better to look at CFG and
+    //             check only uses possibly executed before this callsite.
+
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AANoCapture will get a "isCapturedBefore" functionality at some point to solve this.


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Comment at: llvm/lib/Transforms/IPO/Attributor.cpp:1736
+    if (!NoCaptureAA.isAssumedNoCapture())
+      return indicatePessimisticFixpoint();
+
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make it `isAssumedNoCaptureMaybeReturned`.


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Comment at: llvm/lib/Transforms/IPO/Attributor.cpp:2644
+                                    : "no-capture-maybe-returned"));
   }
 
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I do not understand these changes. Why do they help? Can we extract them into a different commit?


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Comment at: llvm/lib/Transforms/IPO/Attributor.cpp:2914
+      indicatePessimisticFixpoint();
+  }
+
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Again, why is this needed?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D67286/new/

https://reviews.llvm.org/D67286