[PATCH] D142078: [llvm] Move bit counting functions to bit.h (NFC)

[David Blaikie via Phabricator via llvm-commits]

dblaikie added a comment.

Is the plan to migrate callers over to this eventually, and remove the countNnn wrappers?



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Comment at: llvm/include/llvm/ADT/bit.h:44-54
+#ifdef _MSC_VER
+// Declare these intrinsics manually rather including intrin.h. It's very
+// expensive, and MathExtras.h is popular.
+// #include <intrin.h>
+extern "C" {
+unsigned char _BitScanForward(unsigned long *_Index, unsigned long _Mask);
+unsigned char _BitScanForward64(unsigned long *_Index, unsigned __int64 _Mask);
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Instead of this, perhaps we could write small/simple wrappers, avoiding the need to forward declare things from platform headers? & possibly wrapping the basic operations/differences between the platforms in a more direct way, then exposing these higher level primitives based on those abstractions?


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https://reviews.llvm.org/D142078