C++怎么进行内存对齐操作_C++性能优化与alignas/alignof关键字详解

#include <iostream>
int main() {
    std::cout << "alignof(int): " << alignof(int) << "\n";        // 通常为4
    std::cout << "alignof(double): " << alignof(double) << "\n";  // 通常为8
    std::cout << "alignof(void*): " << alignof(void*) << "\n";    // 取决于平台
    return 0;
}

alignas(16) int aligned_array[4];  // 确保数组按16字节对齐
<p>struct alignas(8) Vec3 {
float x, y, z;
}; // 结构体整体按8字节对齐</p><p>alignas(double) char buffer[sizeof(double)]; // 让字符缓冲区具有double的对齐</p>
                    <div class="aritcle_card">
                        <a class="aritcle_card_img" href="/ai/1840">
                            <img src="https://img.php.cn/upload/ai_manual/000/969/633/68b6c8ae5fa40470.png" alt="Change Style AI">
                        </a>
                        <div class="aritcle_card_info">
                            <a href="/ai/1840">Change Style AI</a>
                            <p>多风格照片生成器！AI生成30种照片</p>
                            <div class="">
                                <img src="/static/images/card_xiazai.png" alt="Change Style AI">
                                <span>167</span>
                            </div>
                        </div>
                        <a href="/ai/1840" class="aritcle_card_btn">
                            <span>查看详情</span>
                            <img src="/static/images/cardxiayige-3.png" alt="Change Style AI">
                        </a>
                    </div>
                

#include <immintrin.h>
<p>struct alignas(16) Vec4f {
float data[4];</p><pre class='brush:php;toolbar:false;'>void load(const float* ptr) {
    _mm_load_ps(data, ptr); // 要求data地址16字节对齐
}

alignas(Vec4f) char memory_pool[100 * sizeof(Vec4f)];
Vec4f* vec = new(memory_pool) Vec4f();