expensive_callable

Detailed Description

States that the operation dominates the loop.

Variables
constexpr auto	eve::algo::expensive_callable = ::rbr::flag( expensive_callable_tag{} )

Variable Documentation

expensive_callable

auto eve::algo::expensive_callable = ::rbr::flag( expensive_callable_tag{} )

inlineconstexpr

Header file #include <eve/module/algo.hpp>

namespace eve::algo
{
  inline constexpr auto expensive_callable = eve_implementation_defined;
}

States that the callable or the iterator dominates the loop, and is equivalent to eve::algo::no_aligning, eve::algo::no_unrolling and eve::algo::single_pass together. By default the predicate is assumed to be light, and the loop is unrolled and aligned so that its time is spent in the body rather than around it; if the body is heavy, both are overhead.

std::vector<float> data(1024);
 
// A body of dozens of operations: neither alignment nor unrolling repays its cost.
auto damped = [](auto x) { return eve::sin(x) * eve::exp(-x); };
transform_inplace[expensive_callable](data, damped);

See also

no_aligning, no_unrolling, single_pass