[PATCH] D149421: [KnownBits] Improve `KnownBits::rem(X, Y)` in cases where we can deduce low-bits of output

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added a comment.

KnownBitsTest has an exhaustive test for srem and urem - so the likelihood of bugs surfacing are pretty low.



================
Comment at: llvm/lib/Support/KnownBits.cpp:561
+    KnownOut.Zero |= ZerosMask;
+    return KnownOut;
+  }
----------------
return KnownBits(ZerosMask, OnesMask)


================
Comment at: llvm/lib/Support/KnownBits.cpp:563
+  }
+  return Known;
+}
----------------
return KnownBits(BitWidth)


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D149421/new/

https://reviews.llvm.org/D149421