[clang] [llvm] Match bitsin(typeof(x)) - popcnt(x) to s_bcnt0_i32 on AMDGPU (PR #164847)

[via llvm-commits]

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@@ -93,6 +95,13 @@ static cl::opt<bool> DisableFDivExpand(
   cl::ReallyHidden,
   cl::init(false));
 
+// Disable processing of fdiv so we can better test the backend implementations.
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LU-JOHN wrote:

Is this option necessary?

https://github.com/llvm/llvm-project/pull/164847