Use unchecked fma to speed up spec fun

mborland · mborland · commit 9dc4e7e2d2d0 · 2025-01-07T15:15:37.000-05:00
diff --git a/include/boost/decimal/detail/cmath/impl/remez_series_result.hpp b/include/boost/decimal/detail/cmath/impl/remez_series_result.hpp
@@ -20,7 +20,7 @@ constexpr auto remez_series_result(T x, const Array &coeffs) noexcept
     result = coeffs[0];
     for (std::size_t i {1}; i < coeffs.size(); ++i)
     {
-        result = fma(result, x, coeffs[i]);
+        result = unchecked_fma(result, x, coeffs[i]);
     }
 
     return result;
diff --git a/include/boost/decimal/detail/cmath/impl/taylor_series_result.hpp b/include/boost/decimal/detail/cmath/impl/taylor_series_result.hpp
@@ -21,7 +21,7 @@ constexpr auto taylor_series_result(T x, const Array &coeffs) noexcept
 
     for (std::size_t i = N - 1; i-- > 0;)
     {
-        result = fma(result, x, coeffs[i]);
+        result = unchecked_fma(result, x, coeffs[i]);
     }
 
     return result;

Original file line number	Diff line number	Diff line change
`@@ -20,7 +20,7 @@ constexpr auto remez_series_result(T x, const Array &coeffs) noexcept`
`20`	`20`	`result = coeffs[0];`
`21`	`21`	`for (std::size_t i {1}; i < coeffs.size(); ++i)`
`22`	`22`	`{`
`23`		`- result = fma(result, x, coeffs[i]);`
	`23`	`+ result = unchecked_fma(result, x, coeffs[i]);`
`24`	`24`	`}`
`25`	`25`
`26`	`26`	`return result;`
Original file line number	Diff line number	Diff line change
`@@ -21,7 +21,7 @@ constexpr auto taylor_series_result(T x, const Array &coeffs) noexcept`
`21`	`21`
`22`	`22`	`for (std::size_t i = N - 1; i-- > 0;)`
`23`	`23`	`{`
`24`		`- result = fma(result, x, coeffs[i]);`
	`24`	`+ result = unchecked_fma(result, x, coeffs[i]);`
`25`	`25`	`}`
`26`	`26`
`27`	`27`	`return result;`