diff options
author | Thiago Macieira <thiago.macieira@intel.com> | 2020-06-25 14:05:09 -0700 |
---|---|---|
committer | Thiago Macieira <thiago.macieira@intel.com> | 2022-11-28 10:59:20 -0800 |
commit | 99c7f0419e66692260be56c0385badeacb3f6760 (patch) | |
tree | ae8d1b032bb36c72c102f99d64fda35a9fdedbbb /src/corelib/kernel | |
parent | 21950e3085bd45dbd4b55fb76e3d47319cbb11d7 (diff) |
qfloat16: add support for native _Float16 (C2x extended floating point)
The C++ equivalent is std::float16_t, defined in P1467[1], and is coming
with GCC 13 both in native mode (for x86, using AVX512FP16) and in
emulated mode. The C and C++ types will be the same type (<stdfloat>
simply typedefs).
qfloat16 will need to remain a wrapper with an integer member to keep
ABI with previous Qt versions. Because it is a trivially-copyable small
type, it gets currently passed in registers; the presence of the integer
member means it gets passed in general-purpose registers, while a single
_Float16 member would be passed in a floating-point register. See:
https://gcc.godbolt.org/z/8fEendjff
[1] https://wg21.link/p1467
Change-Id: I8a5b6425b64a4e319b94fffd161be56397cb48e6
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
Diffstat (limited to 'src/corelib/kernel')
-rw-r--r-- | src/corelib/kernel/qmath.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/src/corelib/kernel/qmath.h b/src/corelib/kernel/qmath.h index fd39f46c1b..b1e5b4f17e 100644 --- a/src/corelib/kernel/qmath.h +++ b/src/corelib/kernel/qmath.h @@ -113,7 +113,7 @@ class QHypotHelper public: QHypotHelper(T first) : scale(qAbs(first)), total(1) {} T result() const - { return qIsFinite(scale) ? scale > 0 ? scale * T(std::sqrt(total)) : T(0) : scale; } + { return qIsFinite(scale) ? scale > 0 ? scale * T(qSqrt(total)) : T(0) : scale; } template<typename F, typename ...Fs> auto add(F first, Fs... rest) const @@ -133,7 +133,7 @@ public: return QHypotHelper<R>(scale, total); if (val > scale) { const R ratio = scale / next; - return QHypotHelper<R>(val, total * ratio * ratio + 1); + return QHypotHelper<R>(val, total * ratio * ratio + R(1)); } const R ratio = next / scale; return QHypotHelper<R>(scale, total + ratio * ratio); |