使用SSE Shift获得零

Question

我有这段代码：

#include <immintrin.h>
#include <stdio.h>

void main(){
    int i;
    __m128 x_v, y_v, e_v;
    __m128i mask_v;

    float x[8]={1.0f,2.0f,3.0f,4.0f};
    float y[8]={1.0f,2.0f,3.0f,4.0f};
    int exp0mask = 0xFFFFFFFF;

    for(i=0; i+3<4; i+=4) {
        x_v = _mm_loadu_ps(x+i);
        y_v =  _mm_loadu_ps(y+i);
        mask_v = _mm_set1_epi32(exp0mask);
        e_v = _mm_and_ps(x_v,  _mm_castsi128_ps(mask_v));
        e_v = _mm_castsi128_ps(_mm_srli_epi32(_mm_castps_si128(e_v), 23));
        _mm_storeu_ps(y+i, e_v);
        printf("%f\n", y[i]);
        printf("%f\n", y[i+1]);
        printf("%f\n", y[i+2]);
        printf("%f\n", y[i+3]);
    }
}

这就是结果：

0.000000
0.000000
0.000000
0.000000

x[i]（浮点数组）中的值不为零。我观察到，零结果发生在移位操作_mm_srli_epi32之后。但为什么会这样，我该怎么办？