x86 MASKMOVDQU 指令的所有 16 个字节都必须是有效内存吗？
Must all 16 bytes of an x86 MASKMOVDQU instruction be valid memory?
当使用 x86 MASKMOVDQU 指令时，目标位置是否必须始终有 16 个字节的可写内存，即使某些掩码位为零？
例如，假设我使用 MASKMOVDQU 写入地址 0x12345FFC。 0x12345000 处的页面是有效内存，但 0x12346000 处的页面不是。如果掩码寄存器是0x00000000'00000000'00000000'FFFFFFFF，这个MASKMOVDQU会一直有效吗，还是会出现异常？
英特尔手册说明了以下关于全零掩码的内容，但没有提到我正在谈论的边缘情况：
Behavior with a mask of all 0s is as follows:
• No data will be
written to memory.
• Signaling of breakpoints (code or data) is not
guaranteed; different processor implementations may signal or not
signal these breakpoints.
• Exceptions associated with addressing
memory and page faults may still be signaled (implementation
dependent).
• If the destination memory region is mapped as UC or WP,
enforcement of associated semantics for these memory types is not
guaranteed (that is, is reserved) and is implementation-specific.
参见第三个要点。这特别说明即使所有掩码都为零，异常仍可能发生。当然，这意味着可能会为屏蔽写入生成异常。
的确，AMD手册在这个问题上写的比较清楚：
Exception and trap behavior for elements not selected for storage to
memory are implementation dependent. For instance, a given
implementation may signal a data breakpoint or a page fault for bytes
that are zero-masked and not actually written.
当使用 x86 MASKMOVDQU 指令时，目标位置是否必须始终有 16 个字节的可写内存，即使某些掩码位为零？
例如，假设我使用 MASKMOVDQU 写入地址 0x12345FFC。 0x12345000 处的页面是有效内存，但 0x12346000 处的页面不是。如果掩码寄存器是0x00000000'00000000'00000000'FFFFFFFF，这个MASKMOVDQU会一直有效吗，还是会出现异常？
英特尔手册说明了以下关于全零掩码的内容，但没有提到我正在谈论的边缘情况：
Behavior with a mask of all 0s is as follows:
• No data will be written to memory.
• Signaling of breakpoints (code or data) is not guaranteed; different processor implementations may signal or not signal these breakpoints.
• Exceptions associated with addressing memory and page faults may still be signaled (implementation dependent).
• If the destination memory region is mapped as UC or WP, enforcement of associated semantics for these memory types is not guaranteed (that is, is reserved) and is implementation-specific.
参见第三个要点。这特别说明即使所有掩码都为零，异常仍可能发生。当然，这意味着可能会为屏蔽写入生成异常。
的确，AMD手册在这个问题上写的比较清楚：
Exception and trap behavior for elements not selected for storage to memory are implementation dependent. For instance, a given implementation may signal a data breakpoint or a page fault for bytes that are zero-masked and not actually written.