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f16c: Use the packed intrinsics instead of scalar ones

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MSVC, Apple's Clang and Clang prior to 3.9 do not recognize _cvtss_sh
and _cvtsh_ss. So expand the operation to use directly the packed
intrinsics.

Change-Id: I27b55fdf514247549455fffd14b2046fd638593d
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
This commit is contained in:
Thiago Macieira 2017-04-03 15:41:44 -07:00
parent 264d814773
commit c817b33b45
2 changed files with 10 additions and 9 deletions
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11
config.tests/common/f16c/f16c.cpp
View File

@ -41,14 +41,11 @@
int main(int, char**)
{
float f = 1.f;
unsigned short s = _cvtss_sh(f, 0);
float g = _cvtsh_ss(s);
bool result = f == g;
(void)result;
__m128i a = _mm_setzero_si128();
__m256 b = _mm256_cvtph_ps(a);
__m128i c = _mm256_cvtps_ph(b, 0);
__m128 b = _mm_cvtph_ps(a);
__m256 b256 = _mm256_cvtph_ps(a);
__m128i c = _mm_cvtps_ph(b, 0);
c = _mm256_cvtps_ph(b256, 0);
(void)c;
return 0;
}

8
src/corelib/global/qfloat16.h
View File

@ -118,7 +118,9 @@ QT_WARNING_DISABLE_CLANG("-Wc99-extensions")
inline qfloat16::qfloat16(float f) Q_DECL_NOTHROW
{
#if defined(QT_COMPILER_SUPPORTS_F16C) && defined(__F16C__)
b16 = _cvtss_sh(f, 0);
__m128 packsingle = _mm_set_ss(f);
__m128i packhalf = _mm_cvtps_ph(packsingle, 0);
b16 = _mm_extract_epi16(packhalf, 0);
#elif defined (__ARM_FP16_FORMAT_IEEE)
__fp16 f16 = f;
memcpy(&b16, &f16, sizeof(quint16));
@ -134,7 +136,9 @@ QT_WARNING_POP
inline qfloat16::operator float() const Q_DECL_NOTHROW
{
#if defined(QT_COMPILER_SUPPORTS_F16C) && defined(__F16C__)
return _cvtsh_ss(b16);
__m128i packhalf = _mm_cvtsi32_si128(b16);
__m128 packsingle = _mm_cvtph_ps(packhalf);
return _mm_cvtss_f32(packsingle);
#elif defined (__ARM_FP16_FORMAT_IEEE)
__fp16 f16;
memcpy(&f16, &b16, sizeof(quint16));