// 测试SSE的转换操作
void TestSSEConvert()
{    // 浮点数组
    __declspec(align(16)) float A[4] = { 5.35, 10.70, 16.05, 21.40 };
    __declspec(align(16)) float B[4] = { 5.75, 11.50, 17.25, -25.3 };  __m128 *p = (__m128 *)A;
    __m128 *q = (__m128 *)B;
    __m128  a = p[0];
    __m128  b = q[0];
    printf("a: (%.2f, %.2f, %.2f, %.2f)\t b: (%.2f, %.2f, %.2f, %.2f)\n\n",
        p->m128_f32[0], p->m128_f32[1], p->m128_f32[2], p->m128_f32[3],
        q->m128_f32[0], q->m128_f32[1], q->m128_f32[2], q->m128_f32[3]);    int v1 = _mm_cvtss_si32(a);
    int v2 = _mm_cvtss_si32(b);
    int v3 = _mm_cvttss_si32(a);
    int v4 = _mm_cvttss_si32(b);
    printf("(v1, v2, v3, v4): (%d, %d, %d, %d)\n\n", v1, v2, v3, v4); //__int64 v5 = _mm_cvtss_si64(a);
    //__int64 v6 = _mm_cvttss_si64(a);
    __m64 v5 = _mm_cvtps_pi32(a);
    __m64 v6 = _mm_cvttps_pi32(a);
    printf("v5: (%d, %d)\t v6: (%d, %d)\n\n", v5.m64_i32[0], v5.m64_i32[1], v6.m64_i32[0], v6.m64_i32[1]);    //__m128 v7 = _mm_cvtsi64_ss(a, 123);
    __m128 v7 = _mm_cvtsi32_ss(a, 123);
    __m128 v8 = _mm_cvtpi32_ps(a, v5);
    printf("v7: (%.2f, %.2f, %.2f, %.2f)\n\n", v7.m128_f32[0], v7.m128_f32[1], v7.m128_f32[2], v7.m128_f32[3]);
    printf("v8: (%.2f, %.2f, %.2f, %.2f)\n\n", v8.m128_f32[0], v8.m128_f32[1], v8.m128_f32[2], v8.m128_f32[3]);   __m64  v9  = _mm_cvtps_pi16(b);
    __m128 v10 = _mm_cvtpi16_ps(v9);
    __m128 v11 = _mm_cvtpu16_ps(v9);
    printf("v9: (%d, %d, %d, %d)\n\n", v9.m64_i16[0], v9.m64_i16[1], v9.m64_i16[2], v9.m64_i16[3]);
    printf("v10: (%.2f, %.2f, %.2f, %.2f)\n\n", v10.m128_f32[0], v10.m128_f32[1], v10.m128_f32[2], v10.m128_f32[3]);
    printf("v11: (%.2f, %.2f, %.2f, %.2f)\n\n", v11.m128_f32[0], v11.m128_f32[1], v11.m128_f32[2], v11.m128_f32[3]);  __m64 temp;
    temp.m64_i8[0] = -1;
    temp.m64_i8[1] = 2;
    temp.m64_i8[2] = -3;
    temp.m64_i8[3] = 4;
    __m128 v12 = _mm_cvtpi8_ps(temp);
    __m128 v13 = _mm_cvtpu8_ps(temp);
    printf("v12: (%.2f, %.2f, %.2f, %.2f)\n\n", v12.m128_f32[0], v12.m128_f32[1], v12.m128_f32[2], v12.m128_f32[3]);
    printf("v13: (%.2f, %.2f, %.2f, %.2f)\n\n", v13.m128_f32[0], v13.m128_f32[1], v13.m128_f32[2], v13.m128_f32[3]);  __m64 a1, a2;
    a1.m64_i32[0] = -120;
    a1.m64_i32[1] = 120;
    a2.m64_i32[0] = 256;
    a2.m64_i32[1] = -256;
    __m128 v14 = _mm_cvtpi32x2_ps(a1, a2);
    __m64  v15 = _mm_cvtps_pi16(v14);
    printf("v14: (%.2f, %.2f, %.2f, %.2f)\n\n", v14.m128_f32[0], v14.m128_f32[1], v14.m128_f32[2], v14.m128_f32[3]);
    printf("v15: (%d, %d, %d, %d)\n\n", v15.m64_i16[0], v15.m64_i16[1], v15.m64_i16[2], v15.m64_i16[3]);  float f = _mm_cvtss_f32(a);
    printf("_mm_cvtss_f32(a) = %.2f\n\n", f);    __m64 v16 = _mm_cvtps_pi8(v14);
    printf("v16: (%d, %d, %d, %d)\n\n", v16.m64_i8[0], v16.m64_i8[1], v16.m64_i8[2], v16.m64_i8[3]);
}

   

   Remark:  由于一些奇怪的原因，上面出现 -1.#J 的地方是显示错误，分别纠正如下：

// 测试SSE加载操作
void TestSSELoad()
{    // 浮点数组
    __declspec(align(16)) float A[2] = { 5.35, 10.70 };
    const __m64 *p = (const __m64 *)A;
    printf("(p0, p1): (%.2f, %.2f)\n\n", p->m64_f32[0], p->m64_f32[1]); __m128 a;
    a.m128_f32[0] = 80.45;
    a.m128_f32[1] = 85.55;
    a.m128_f32[2] = 90.65;
    a.m128_f32[3] = 95.75; __m128 v1 = _mm_loadh_pi(a, p);
    __m128 v2 = _mm_loadl_pi(a, p);
    printf("v1: (%.2f, %.2f, %.2f, %.2f)\n\n", v1.m128_f32[0], v1.m128_f32[1], v1.m128_f32[2], v1.m128_f32[3]);
    printf("v2: (%.2f, %.2f, %.2f, %.2f)\n\n", v2.m128_f32[0], v2.m128_f32[1], v2.m128_f32[2], v2.m128_f32[3]);   const float f  = 100.85;
    const float *q = &f;
    __m128 v3 = _mm_load_ss(q);
    __m128 v4 = _mm_load1_ps(q);
    printf("v3: (%.2f, %.2f, %.2f, %.2f)\n\n", v3.m128_f32[0], v3.m128_f32[1], v3.m128_f32[2], v3.m128_f32[3]);
    printf("v4: (%.2f, %.2f, %.2f, %.2f)\n\n", v4.m128_f32[0], v4.m128_f32[1], v4.m128_f32[2], v4.m128_f32[3]);   __declspec(align(16)) const float r[4] = {1.11, 2.22, 3.33, 4.44};
    __m128 v5 = _mm_loadu_ps(r);
    __m128 v6 = _mm_loadr_ps(r);       // 注意此处地址r必须16字节对齐
    printf("v5: (%.2f, %.2f, %.2f, %.2f)\n\n", v5.m128_f32[0], v5.m128_f32[1], v5.m128_f32[2], v5.m128_f32[3]);
    printf("v6: (%.2f, %.2f, %.2f, %.2f)\n\n", v6.m128_f32[0], v6.m128_f32[1], v6.m128_f32[2], v6.m128_f32[3]);
}

测试结果:

   

// 测试SSE置位操作
void TestSSESet()
{    __m128 v0 = _mm_setzero_ps();
    __m128 v1 = _mm_set_ss(3.55);
    __m128 v2 = _mm_set1_ps(3.55);
    __m128 v3 = _mm_set_ps(1.11, 2.22, 3.33, 4.44);
    __m128 v4 = _mm_setr_ps(1.11, 2.22, 3.33, 4.44);
    printf("v0: (%.2f, %.2f, %.2f, %.2f)\n\n", v0.m128_f32[0], v0.m128_f32[1], v0.m128_f32[2], v0.m128_f32[3]);
    printf("v1: (%.2f, %.2f, %.2f, %.2f)\n\n", v1.m128_f32[0], v1.m128_f32[1], v1.m128_f32[2], v1.m128_f32[3]);
    printf("v2: (%.2f, %.2f, %.2f, %.2f)\n\n", v2.m128_f32[0], v2.m128_f32[1], v2.m128_f32[2], v2.m128_f32[3]);
    printf("v3: (%.2f, %.2f, %.2f, %.2f)\n\n", v3.m128_f32[0], v3.m128_f32[1], v3.m128_f32[2], v3.m128_f32[3]);
    printf("v4: (%.2f, %.2f, %.2f, %.2f)\n\n", v4.m128_f32[0], v4.m128_f32[1], v4.m128_f32[2], v4.m128_f32[3]);
}

测试结果:

4.   SSE的存储操作

// 测试SSE存储操作
void TestSSEStore()
{    __m128 a;
    a.m128_f32[0] = 80.45;
    a.m128_f32[1] = 85.55;
    a.m128_f32[2] = 90.65;
    a.m128_f32[3] = 95.75; __declspec(align(16)) float A[2] = { 0 };
    __declspec(align(16)) float B[2] = { 0 };
    __m64 *p = (__m64 *)A;
    __m64 *q = (__m64 *)B;
    _mm_storeh_pi(p, a);
    _mm_storel_pi(q, a);
    printf("(p0, p1): (%.2f, %.2f)\n\n", p->m64_f32[0], p->m64_f32[1]);
    printf("(q0, q1): (%.2f, %.2f)\n\n", q->m64_f32[0], q->m64_f32[1]); __declspec(align(16)) float f[4] = { 0 };
    _mm_store_ss(&f[0], a);
    printf("f[0]: %.2f\n\n", f[0]);   _mm_store1_ps(f, a);
    printf("f: (%.2f, %.2f, %.2f, %.2f)\n\n", f[0], f[1], f[2], f[3]);    _mm_store_ps(f, a);
    printf("f: (%.2f, %.2f, %.2f, %.2f)\n\n", f[0], f[1], f[2], f[3]);    float g[4] = { 0 };
    _mm_storeu_ps(g, a);
    printf("g: (%.2f, %.2f, %.2f, %.2f)\n\n", f[0], f[1], f[2], f[3]);    _mm_storer_ps(f, a);
    printf("f: (%.2f, %.2f, %.2f, %.2f)\n\n", f[0], f[1], f[2], f[3]);
}