Merge pull request cppfastio#2 from trcrsired/master

m

benchmark/0004.file_io_floating/charconv_general.cc

@@ -26,7 +26,7 @@ int main()
 			auto [res, ec] = std::to_chars(buffer, start + 40, e, std::chars_format::general);
 			*res = '\n';
 			++res;
-			write(file, start, res);
+			::fast_io::operations::write_all(file, start, res);
 		}
 	}
 }

benchmark/0004.file_io_floating/charconv_general_float.cc

@@ -26,7 +26,7 @@ int main()
 			auto [res, ec] = std::to_chars(buffer, start + 40, e, std::chars_format::general);
 			*res = '\n';
 			++res;
-			write(file, start, res);
+			::fast_io::operations::write_all(file, start, res);
 		}
 	}
 }

benchmark/0004.file_io_floating/charconv_hexfloat.cc

@@ -26,7 +26,7 @@ int main()
 			auto [res, ec] = std::to_chars(buffer, start + 40, e, std::chars_format::hex);
 			*res = '\n';
 			++res;
-			write(file, start, res);
+			::fast_io::operations::write_all(file, start, res);
 		}
 	}
 }

benchmark/0004.file_io_floating/charconv_hexfloat_float.cc

@@ -26,7 +26,7 @@ int main()
 			auto [res, ec] = std::to_chars(buffer, start + 40, e, std::chars_format::hex);
 			*res = '\n';
 			++res;
-			write(file, start, res);
+			::fast_io::operations::write_all(file, start, res);
 		}
 	}
 }

include/fast_io_core.h

@@ -43,6 +43,7 @@
 #if defined(_MSC_VER) && !defined(__clang__)
 #include "fast_io_core_impl/intrinsics/msvc/impl.h"
 #endif
+#include "fast_io_core_impl/bitops/impl.h"
 #include "fast_io_core_impl/freestanding/impl.h"
 #include "fast_io_core_impl/terminate.h"
 #include "fast_io_dsal/impl/freestanding.h"

include/fast_io_core_impl/bitops/impl.h

@@ -0,0 +1,3 @@
+#pragma once
+
+#include "rtz.h"

include/fast_io_core_impl/bitops/rtz.h

@@ -0,0 +1,204 @@
+#pragma once
+/*
+Reference from
+https://github.com/cppalliance/decimal/blob/develop/include/boost/decimal/detail/remove_trailing_zeros.hpp
+granlund_montgomery_branchless
+*/
+namespace fast_io::bitops
+{
+
+template <typename T>
+struct rtz_result
+{
+	using value_type = T;
+	T value;
+	std::size_t n;
+};
+
+namespace details
+{
+
+template <bool iec559, typename T>
+inline constexpr ::fast_io::bitops::rtz_result<T> rtz_impl(T n) noexcept
+{
+	if constexpr (::std::numeric_limits<T>::digits == 64)
+	{
+		if constexpr (!::std::same_as<T, ::std::uint_least64_t>)
+		{
+#ifdef __cpp_lib_bit_cast
+			return __builtin_bit_cast(::fast_io::bitops::rtz_result<T>,
+									  ::fast_io::bitops::details::rtz_impl<iec559>(static_cast<::std::uint_least64_t>(n)));
+#else
+			auto [v, s] = ::fast_io::bitops::details::rtz_impl<iec559>(static_cast<::std::uint_least64_t>(n));
+			return {v, s};
+#endif
+		}
+		else
+		{
+			std::size_t s{};
+
+			if constexpr(!iec559)
+			{
+				constexpr ::std::uint_least64_t c0{230079197716545u};
+				::std::uint_least64_t r{::std::rotr(static_cast<std::uint64_t>(n * c0), 16)};
+				constexpr ::std::uint_least64_t d0{1845u};
+				bool b{r < d0};
+				s += s;
+				s += b;
+				n = b ? r : n;
+			}
+
+			constexpr ::std::uint_least64_t c0{28999941890838049u};
+			::std::uint_least64_t r{::std::rotr(static_cast<std::uint64_t>(n * c0), 8)};
+			constexpr ::std::uint_least64_t d0{184467440738u};
+			bool b{r < d0};
+			s += s;
+			s += b;
+			n = b ? r : n;
+
+			constexpr ::std::uint_least64_t c1{182622766329724561u};
+			r = ::std::rotr(static_cast<std::uint64_t>(n * c1), 4);
+			constexpr ::std::uint_least64_t d1{1844674407370956u};
+			b = r < d1;
+			s += s;
+			s += b;
+			n = b ? r : n;
+
+			constexpr ::std::uint_least64_t c2{10330176681277348905u};
+			r = ::std::rotr(static_cast<std::uint64_t>(n * c2), 2);
+			constexpr ::std::uint_least64_t d2{184467440737095517u};
+			b = r < d2;
+			s += s;
+			s += b;
+			n = b ? r : n;
+
+			constexpr ::std::uint_least64_t c3{14757395258967641293u};
+			r = ::std::rotr(static_cast<std::uint64_t>(n * c3), 1);
+			constexpr ::std::uint_least64_t d3{1844674407370955162u};
+			b = r < d3;
+			s += s;
+			s += b;
+			n = b ? r : n;
+
+			return {n, s};
+		}
+	}
+	else if constexpr (::std::numeric_limits<T>::digits == 32)
+	{
+		if constexpr (!::std::same_as<T, ::std::uint_least32_t>)
+		{
+#ifdef __cpp_lib_bit_cast
+			return __builtin_bit_cast(::fast_io::bitops::rtz_result<T>,
+									  ::fast_io::bitops::details::rtz_impl<iec559>(static_cast<::std::uint_least32_t>(n)));
+#else
+			auto [v, s] = ::fast_io::bitops::details::rtz_impl<iec559>(static_cast<::std::uint_least32_t>(n));
+			return {v, s};
+#endif
+		}
+		else
+		{
+			std::size_t s{};
+
+			if constexpr(!iec559)
+			{
+				constexpr ::std::uint_least64_t c0{15273505u};
+				::std::uint_least64_t r{::std::rotr(static_cast<std::uint32_t>(n * c0), 8)};
+				constexpr ::std::uint_least64_t d0{43u};
+				bool b{r < d0};
+				s += s;
+				s += b;
+				n = b ? r : n;
+			}
+
+			constexpr ::std::uint_least32_t c0{184254097u};
+			::std::uint_least32_t r{::std::rotr(static_cast<std::uint32_t>(n * c0), 4)};
+			constexpr ::std::uint_least32_t d0{429497u};
+			bool b{r < d0};
+			s += s;
+			s += b;
+			n = b ? r : n;
+
+			constexpr ::std::uint_least32_t d1{42949673u};
+			r = ::std::rotr(static_cast<std::uint32_t>(n * d1), 2);
+			b = r < d1;
+			s += s;
+			s += b;
+			n = b ? r : n;
+
+			constexpr ::std::uint_least32_t c2{1288490189u};
+			r = ::std::rotr(static_cast<std::uint32_t>(n * c2), 1);
+			constexpr ::std::uint_least32_t d2{429496730u};
+			b = r < d2;
+			s += s;
+			s += b;
+			n = b ? r : n;
+
+			return {n, s};
+		}
+	}
+#if 0
+	else if constexpr (::std::numeric_limits<T>::digits == 16)
+	{
+		if constexpr (!::std::same_as<T, ::std::uint_least16_t>)
+		{
+#ifdef __cpp_lib_bit_cast
+			return __builtin_bit_cast(::fast_io::bitops::rtz_result<T>,
+									  ::fast_io::bitops::details::rtz_impl<iec559>(static_cast<::std::uint_least32_t>(n)));
+#else
+			auto [v, s] = ::fast_io::bitops::details::rtz_impl<false>(static_cast<::std::uint_least32_t>(n));
+			return {v, s};
+#endif
+		}
+		else
+		{
+
+		}
+	}
+#endif
+	else if constexpr (::std::numeric_limits<T>::digits == 16 || ::std::numeric_limits<T>::digits == 8)
+	{
+		auto [v, s] = ::fast_io::bitops::details::rtz_impl<true>(static_cast<::std::uint_least32_t>(n));
+		return {static_cast<T>(v), s};
+	}
+	else
+	{
+		::std::size_t s{};
+		while (true)
+		{
+			auto const r{n % 100};
+			if (r == 0)
+			{
+				n /= 100;
+				s += 2;
+			}
+			else
+			{
+				break;
+			}
+		}
+		auto const r{n % 10};
+		if (r == 0)
+		{
+			n /= 10;
+			++s;
+		}
+		return {n, s};
+	}
+}
+
+
+}
+
+template <typename T>
+inline constexpr ::fast_io::bitops::rtz_result<T> rtz_iec559(T n) noexcept
+{
+	return ::fast_io::bitops::details::rtz_impl<true>(n);
+}
+
+template <typename T>
+inline constexpr ::fast_io::bitops::rtz_result<T> rtz(T n) noexcept
+{
+	return ::fast_io::bitops::details::rtz_impl<false>(n);
+}
+
+} // namespace fast_io::bitops

include/fast_io_core_impl/intrinsics/impl.h

@@ -2,3 +2,4 @@
 
 #include "carry.h"
 #include "udivmod.h"
+#include "umul.h"

include/fast_io_core_impl/intrinsics/msvc/x86.h

@@ -20,6 +20,8 @@ extern "C"
 	unsigned __int64 _udiv128(unsigned __int64, unsigned __int64, unsigned __int64, unsigned __int64 *);
 	unsigned __int64 __shiftleft128(unsigned __int64, unsigned __int64, unsigned char);
 	unsigned __int64 __shiftright128(unsigned __int64, unsigned __int64, unsigned char);
+	unsigned __int64 _umul128(unsigned __int64, unsigned __int64, unsigned __int64 *);
+	unsigned __int64 __umulh(unsigned __int64, unsigned __int64);
 }
 
 } // namespace fast_io::intrinsics::msvc::x86