[PATCH] D71660: [ValueTracking] isKnownNonZero() should take non-null-ness assumptions into consideration (PR43267)

[Dávid Bolvanský via Phabricator via llvm-commits]

xbolva00 added inline comments.


================
Comment at: llvm/lib/Analysis/ValueTracking.cpp:623
+        return true;
+    }
+  }
----------------
nikic wrote:
> lebedev.ri wrote:
> > jdoerfert wrote:
> > > < is also fine, however unlikely.
> > Right, https://rise4fun.com/Alive/plslNp
> As you went through the effort of supporting different predicates, possibly extend this to also handle non-zero constant? That is, not just `x > 0` but also `x > 100`. Something along the lines of...
> 
> ```
> if (!match(Cmp, m_ICmp(Pred, m_V, m_APInt(C))))
>   return false;
> 
> // Possibly without the non-canonical predicates?
> switch (Pred) {
> case ICmpInst::ICMP_NE:
>   return C->isNullValue();
> case ICmpInst::ICMP_UGT:
>   return true;
> case ICmpInst::ICMP_UGE:
>   return !C->isNullValue();
> case ICmpInst::ICMP_SGT:
>   return C->isNonNegative();
> case ICmpInst::ICMP_SGE:
>   return C->isStrictlyPositive();
> case ICmpInst::ICMP_SLT:
>   return !C->isStrictlyPositive();
> case ICmpInst::ICMP_SLE:
>   return C->isNegative();
> }
> ```
Tests?


================
Comment at: llvm/lib/Analysis/ValueTracking.cpp:593
+    CallInst *I = cast<CallInst>(AssumeVH);
+    assert(I->getParent()->getParent() == Q.CxtI->getParent()->getParent() &&
+           "Got assumption for the wrong function!");
----------------
getFunction()?


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  https://reviews.llvm.org/D71660/new/

https://reviews.llvm.org/D71660