[llvm] [IPSCCP] Infer nonnull return attribute (PR #106553)

[Nikita Popov via llvm-commits]

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@@ -296,6 +296,14 @@ static bool runIPSCCP(
       F->addRangeRetAttr(CR);
       continue;
     }
+    // Infer nonnull return attribute.
+    if (F->getReturnType()->isPointerTy() && ReturnValue.isNotConstant() &&
+        ReturnValue.getNotConstant()->isNullValue() &&
+        !F->hasRetAttribute(Attribute::NonNull) &&
+        !F->hasRetAttribute(Attribute::Dereferenceable)) {
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nikic wrote:

Good point, I dropped the check. FunctionAttrs doesn't check this either.

https://github.com/llvm/llvm-project/pull/106553