[llvm] [GlobalISel] Add computeNumSignBits for SHL (PR #152067)

[David Green via llvm-commits]

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@@ -2051,6 +2083,7 @@ unsigned GISelValueTracking::computeNumSignBits(Register R,
   // Okay, we know that the sign bit in Mask is set.  Use CLO to determine
   // the number of identical bits in the top of the input value.
   Mask <<= Mask.getBitWidth() - TyBits;
+  LLVM_DEBUG(dbgs() << "Mask.countl_one(): " << Mask.countl_one() << "\n");
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davemgreen wrote:

This debug be removed now.

https://github.com/llvm/llvm-project/pull/152067