_mm256_cmp_ps vs _mm256_cmp_pd

cmp_check.c

// This sketch essentially checks if all elements of AVX vector are greater than zero
// In infinite loop we ensure equality of two implementations
//
// gcc -mavx cmp_check.c -o cmp_check -O3 -ffast-math

#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <x86intrin.h>

int main(int argc, char* argv[])
{
	const __m256d double4_0_0_0_0 = _mm256_setzero_pd();

	double dinvrandmax = 1.0 / RAND_MAX;

	while (1)
	{
		int result1 = 0, result2 = 0;

		double values[4] __attribute__((aligned(64)));
		values[0] = (0.5  - rand() * dinvrandmax) * 2;
		values[1] = (0.5  - rand() * dinvrandmax) * 2;
		values[2] = (0.5  - rand() * dinvrandmax) * 2;
		values[3] = (0.5  - rand() * dinvrandmax) * 2;
		const __m256d val = _mm256_load_pd(values);

		values[rand() % 4] = rand() % 2;

		// What's being done in hddm-solver/AVX
		const __m256d d1 = (__m256d)_mm256_cmp_ps((__m256)val, (__m256)double4_0_0_0_0, _CMP_GT_OQ);
		if (_mm256_movemask_pd(d1) != 0xf)
			result1 = 1;

		// What logically should be done instead
		const __m256d d2 = _mm256_cmp_pd(val, double4_0_0_0_0, _CMP_GT_OQ);
		if (_mm256_movemask_pd(d2) != 0xf)
			result2 = 1;

		printf("%f %f %f %f %d %d\n", values[0], values[1], values[2], values[3], result1, result2);

		// Apparently, results are always equal.	
		assert(result1 == result2);
	}

	return 0;
}