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x86 asm: addpd managed to extract doubles

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Ciro Santilli 六四事件 法轮功
2019-06-01 00:00:00 +00:00
parent a90271c6af
commit 26183613e5
1 changed files with 16 additions and 12 deletions
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28
userland/arch/x86_64/intrinsics/addpd.c
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@@ -18,13 +18,19 @@ int main(void) {
*/ */
float f; float f;
_MM_EXTRACT_FLOAT(f, output, 3); _MM_EXTRACT_FLOAT(f, output, 3);
assert(f == 7.0f); assert(f == 7.0f);
_MM_EXTRACT_FLOAT(f, output, 2); _MM_EXTRACT_FLOAT(f, output, 2);
assert(f == 9.0f); assert(f == 9.0f);
_MM_EXTRACT_FLOAT(f, output, 1); _MM_EXTRACT_FLOAT(f, output, 1);
assert(f == 11.0f); assert(f == 11.0f);
_MM_EXTRACT_FLOAT(f, output, 0); _MM_EXTRACT_FLOAT(f, output, 0);
assert(f == 13.0f); assert(f == 13.0f);
/* And we also have _mm_cvtss_f32 + _mm_shuffle_ps, */
assert(_mm_cvtss_f32(output) == 13.0f);
assert(_mm_cvtss_f32(_mm_shuffle_ps(output, output, 1)) == 11.0f);
assert(_mm_cvtss_f32(_mm_shuffle_ps(output, output, 2)) == 9.0f);
assert(_mm_cvtss_f32(_mm_shuffle_ps(output, output, 3)) == 7.0f);
} }
/* 64-bit add (addpd). */ /* 64-bit add (addpd). */
@@ -32,14 +38,12 @@ int main(void) {
__m128d input0 = _mm_set_pd(1.5, 2.5); __m128d input0 = _mm_set_pd(1.5, 2.5);
__m128d input1 = _mm_set_pd(5.5, 6.5); __m128d input1 = _mm_set_pd(5.5, 6.5);
__m128d output = _mm_add_pd(input0, input1); __m128d output = _mm_add_pd(input0, input1);
double d; /* OK, and this is how we get the doubles out:
/* TODO: there is no _MM_EXTRACT_DOUBLE, and the asserts below fail. */ * with _mm_cvtsd_f64 + _mm_unpackhi_pd
#if 0 * https://stackoverflow.com/questions/19359372/mm-cvtsd-f64-analogon-for-higher-order-floating-point
_MM_EXTRACT_FLOAT(d, output, 1); */
assert(d == 7.0); assert(_mm_cvtsd_f64(output) == 9.0);
_MM_EXTRACT_FLOAT(d, output, 0); assert(_mm_cvtsd_f64(_mm_unpackhi_pd(output, output)) == 7.0);
assert(d == 9.0);
#endif
} }
return 0; return 0;