fms

auto eve::fms = functor<fms_t>

inlineconstexpr

Callable Signatures

namespace eve
{
   // Regular overload
   constexpr auto fms(value auto x, value auto y, value auto z)                          noexcept; // 1
 
   // Lanes masking
   constexpr auto fms[conditional_expr auto c](value auto x, value auto y, value auto z) noexcept; // 2
   constexpr auto fms[logical_value auto m](value auto x, value auto y, value auto z)    noexcept; // 2
 
   // Semantic option
   constexpr auto fms[pedantic](value auto x, value auto y, value auto z)                noexcept; // 3
   constexpr auto fms[promote](value auto x, value auto y, value auto z)                 noexcept; // 4
}

Parameters

• x, y, z : values.
• c: Conditional expression masking the operation.
• m: Logical value masking the operation.

Return value

1. The value of x*y-z as if calculated to infinite precision and rounded once is returned, but only if the hardware is in capacity to do it at reasonable cost.
2. The operation is performed conditionnaly
3. pedantic option always ensures the full compliance to fam properties. This can be very expensive if the system has no hardware capability.
4. The operation is performed as if the parameters where promoted to the common type of the three parameters.

External references

• C++ standard reference

Example

// revision 0
#include <eve/module/core.hpp>
#include <iostream>
#include <iomanip>
int main()
{
  eve::wide wf0{0.0, 1.0, 2.0, 3.0, -1.0, -2.0, -3.0, -4.0};
  eve::wide wf1{0.0, -4.0, 1.0, -1.0, 2.0, -2.0, 3.0, -3.0};
  eve::wide wf2{0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0};
  eve::wide wi0{0, 1, 2, 3, -1, -2, -3, -4};
  eve::wide wi1{0, -4, 1, -1, 2, -2, 3, -3};
  eve::wide wi2{0, 1, 2 ,3, 4, 5, 6, 7};
  eve::wide wu0{0u, 1u, 2u, 3u, 4u, 5u, 6u, 7u};
  eve::wide wu1{7u, 6u, 5u, 4u, 3u, 2u, 1u, 0u};
  eve::wide wu2{0u, 2u, 4u, 6u, 1u, 3u, 5u, 7u};
 
  std::cout << "<- wf0                                = " << wf0 << "\n";
  std::cout << "<- wf1                                = " << wf1 << "\n";
  std::cout << "<- wf2                                = " << wf2 << "\n";
  std::cout << "<- wi0                                = " << wi0 << "\n";
  std::cout << "<- wi1                                = " << wi1 << "\n";
  std::cout << "<- wi2                                = " << wi2 << "\n";
  std::cout << "<- wu0                                = " << wu0 << "\n";
  std::cout << "<- wu1                                = " << wu1 << "\n";
  std::cout << "<- wu2                                = " << wu2 << "\n";
 
  std::cout << "-> fma(wf0, wf1, wf2)                 = " << eve::fma(wf0, wf1, wf2) << "\n";
  std::cout << "-> fma[ignore_last(2)](wf0, wf1, wf2) = " << eve::fma[eve::ignore_last(2)](wf0, wf1, wf2) << "\n";
  std::cout << "-> fma[wf0 != 0](wf0, wf1, wf2)       = " << eve::fma[wf0 != 0](wf0, wf1, wf2) << "\n";
  std::cout << "-> fma[pedantic](wf0, wf1, wf2)       = " << eve::fma[eve::pedantic](wf0, wf1, wf2) << "\n";
  std::cout << "-> fma[promote](wf0, wf1, wf2)        = " << eve::fma[eve::promote](wf0, wf1, wf2) << "\n";
  std::cout << "-> fma(wu0, wu1, wu2)                 = " << eve::fma(wu0, wu1, wu2) << "\n";
  std::cout << "-> fma[ignore_last(2)](wu0, wu1, wu2) = " << eve::fma[eve::ignore_last(2)](wu0, wu1, wu2) << "\n";
  std::cout << "-> fma[wu0 != 0](wu0, wu1, wu2)       = " << eve::fma[wu0 != 0](wu0, wu1, wu2) << "\n";
  std::cout << "-> fma[pedantic](wu0, wu1, wu2)       = " << eve::fma[eve::pedantic](wu0, wu1, wu2) << "\n";
  std::cout << "-> fma[promote](wu0, wu1, wu2)        = " << eve::fma[eve::promote](wu0, wu1, wu2) << "\n";
  std::cout << "-> fma(wi0, wi1, wi2)                 = " << eve::fma(wi0, wi1, wi2) << "\n";
  std::cout << "-> fma[ignore_last(2)](wi0, wi1, wi2) = " << eve::fma[eve::ignore_last(2)](wi0, wi1, wi2) << "\n";
  std::cout << "-> fma[wi0 != 0](wi0, wi1, wi2)       = " << eve::fma[wi0 != 0](wi0, wi1, wi2) << "\n";
  std::cout << "-> fma[pedantic](wi0, wi1, wi2)       = " << eve::fma[eve::pedantic](wi0, wi1, wi2) << "\n";
  std::cout << "-> fma[promote](wi0, wi1, wi2)        = " << eve::fma[eve::promote](wi0, wi1, wi2) << "\n";
 
  std::cout << std::setprecision(20) << "-> fma(wf0, wf1, wf2)          = " << eve::fma(wf0, wf1, wf2) << "\n";
  std::cout << std::setprecision(20) << "-> fma[lower](wf0, wf1, wf2)   = " << eve::fma[eve::lower](wf0, wf1, wf2) << "\n";
  std::cout << std::setprecision(20) << "-> fma[upper](wf0, wf1, wf2)   = " << eve::fma[eve::upper](wf0, wf1, wf2) << "\n";
  std::cout << std::setprecision(20) << "-> fma[lower][strict](wf0, wf1, wf2)   = " << eve::fma[eve::lower][eve::strict](wf0, wf1, wf2) << "\n";
  std::cout << std::setprecision(20) << "-> fma[upper][strict](wf0, wf1, wf2)   = " << eve::fma[eve::upper][eve::strict](wf0, wf1, wf2) << "\n";
}