[PATCH] D84007: [ValueTracking] Change canCreatePoison to take Operator, add canCreateUndef

[Johannes Doerfert via Phabricator via llvm-commits]

jdoerfert added inline comments.


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Comment at: llvm/include/llvm/Analysis/ValueTracking.h:607
+  /// poison from non-undef & non-poison operands.
+  bool canCreateUndef(const Operator *Op, bool ConsiderPoisonAsUndef);
 
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Drive by: Now that I see this, I would prefer the public API to have two functions. I'm fine if others disagree but for the users it seems more natural to have `canCreateUndef` and `canCreateUndefOrPoison`, (and maybe `canCreatePoison`).


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Comment at: llvm/lib/Analysis/ValueTracking.cpp:4783
+
+  return false;
 }
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This seems wrong. A load of an uninitialized location should produce `undef` for example, shouldn't it? I fear there are way more things that can produce `undef`. The default should be true here.


Repository:
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  https://reviews.llvm.org/D84007/new/

https://reviews.llvm.org/D84007