tword、oword 和 yword 操作数的大小是多少? [英] What are the sizes of tword, oword and yword operands?

问题描述

NASM/YASM 手册?在相关说明中，这些名称是否有技巧或潜在的想法?有没有办法给更大的字长指定逻辑名称?

What are the sizes of tword, oword and yword operands, as used in the NASM/YASM manual? And on a related note, is there a trick or underlying idea to these names? Is there a way by which bigger word sizes are given logical names?

我知道虽然系统之间的字长可能不同，但 NASM word 是 2 个字节，dword 是两倍(4 个字节)，qword 是一个四字(8 个字节)，但是……tword 是一个三字(6 个字节)吗?对于 oword 和 yword，我什至想不出合理的含义.

I know that while word sizes may differ between systems, a NASM word is 2 bytes, dword is double that (4 bytes), qword is a quad word (8 bytes), but... is tword a triple word (6 bytes)? And for oword and yword I can't even think of a plausible meaning.

请注意，这可能是一个简单的问题，但我找不到答案.在 NASM 和 YASM 手册中没有解释这些大小，甚至在 DQ、DT、DY、RESQ 中也没有解释>、REST、RESY 伪指令.我在某处读到 MASM 使用类似的系统，但也找不到任何相关信息.

Note that it is probably an easy question, but I couldn't find an answer. In the NASM and YASM manuals these sizes are not explained, not even at the DQ, DT, DY, RESQ, REST, RESY pseudo-instructions. I read somewhere that MASM uses a similar system, but could not find anything on that either.

根据答案，这是完整列表:

Based on the answers, this is the complete list:

• 1 字节(8 位):byte、DB、RESB
• 2 字节(16 位):word、DW、RESW
• 4 字节(32 位):dword、DD、RESD
• 8 字节(64 位):qword、DQ、RESQ
• 10 字节(80 位):tword、DT、REST
• 16 字节(128 位):oword、DO、RESO、DDQ、RESDQ
• 32 字节(256 位):yword、DY、RESY
• 64 字节(512 位):zword、DZ、RESZ

• 1 byte (8 bit): byte, DB, RESB
• 2 bytes (16 bit): word, DW, RESW
• 4 bytes (32 bit): dword, DD, RESD
• 8 bytes (64 bit): qword, DQ, RESQ
• 10 bytes (80 bit): tword, DT, REST
• 16 bytes (128 bit): oword, DO, RESO, DDQ, RESDQ
• 32 bytes (256 bit): yword, DY, RESY
• 64 bytes (512 bit): zword, DZ, RESZ

推荐答案

看nasm 源，它看起来像:

• 'oword'/'DO' 是word"的 8 倍(O 代表octoword")，与 dqword(double-quad")同义；这将是 128 位，对应于 SSE 向量寄存器的大小.
• 'tword'/'DT' 是 80 位(T 代表ten 字节")，这是 Intel x87 浮点寄存器的完整大小.
• 'yword'/'DY' 是 256 位，Y 可能是英特尔 AVX 扩展中 256 位向量寄存器的 YMM 名称的助记符.
• 'zword'/'DZ' 是 512 位，Z 表示英特尔 AVX-512 扩展中 512 位向量寄存器的 ZMM 名称.

• 'oword'/'DO' is 8 times as big as "word" (O for "octoword"), synonymous with dqword ("double-quad"); that would be 128 bits, corresponding to the size of an SSE vector register.
• 'tword'/'DT' is 80 bits (T for "ten bytes"), the full size of an Intel x87 floating point register.
• 'yword'/'DY' is 256 bits, and the Y is presumably mnemonic for the YMM names of the 256-bit vector registers in the Intel AVX extensions.
• 'zword'/'DZ' is 512 bits, Z for the ZMM names of the 512-bit vector registers in the Intel AVX-512 extensions.

所以，这不完全是一个合乎逻辑的命名约定；它刚刚长大".

So, it's not exactly a logical naming convention; "it just growed".

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