[libcxx-commits] [libcxx] [Ryu, performance] Use _BitScanForward64 more often, by fixing availability detection, avoiding calling _BitScanForward twice (PR #142000)

[Nikolas Klauser via libcxx-commits]

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@@ -229,9 +229,6 @@ _LIBCPP_HARDENING_MODE_DEBUG
 #    if defined(_MSC_VER) && !defined(__MINGW32__)
 #      define _LIBCPP_MSVCRT // Using Microsoft's C Runtime library
 #    endif
-#    if (defined(_M_AMD64) || defined(__x86_64__)) || (defined(_M_ARM) || defined(__arm__))
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philnik777 wrote:

Please don't touch the C++03 headers.

https://github.com/llvm/llvm-project/pull/142000