[PATCH] D51112: [ValueTracking] Teach computeNumSignBits to understand min/max clamp patterns with constant/splat values

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: lib/Analysis/ValueTracking.cpp:2385
+
+        if (CLow->sle(*CHigh)) {
+          Tmp = ComputeNumSignBits(LHS2, Depth + 1, Q);
----------------
efriedma wrote:
> CLow and CHigh have to be constants so you can perform this "sle" check?
Maybe we could use computeKnownBits to prove an ordering of Low/High in some other cases using leading zeros/ones?


https://reviews.llvm.org/D51112