[PATCH] D99135: [deref] Implement initial set of inference rules for deref-at-point

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/lib/IR/Value.cpp:741
+  // *) An alloca is deallocated when the function returns
+  if (isa<GlobalValue>(V) || isa<Constant>(V) || isa<AllocaInst>(V))
+    return false;
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GlobalValue is a subtype of Constant, no need to check it separately.


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Comment at: llvm/lib/IR/Value.cpp:746
+    // An argument to a function which neither frees, nor can arrange
+    // for another thread to free on it's behalf, can not be freed in it's
+    // defined scope.
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nit: it's -> its


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Comment at: llvm/lib/IR/Value.cpp:750
+    if (F->doesNotFreeMemory() && F->hasNoSync())
+      return false;
+  }
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I don't really get why this code is specific to arguments. Shouldn't this hold for any SSA value inside the function? Sure, it can get freed after the function returns/unwinds, but not while the SSA value is active. Am I missing something here?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D99135/new/

https://reviews.llvm.org/D99135