我知道啥意思了 但这个意思好复杂啊 开始学不要管这个。。。
如果想知道详细信息看intel手册中如下部分及相关内容
你可能会说看不懂 那就不要管这个概念了 记住寄存器的用法就好了
The special uses of general-purpose registers by instructions are described in
Chapter 5, “Instruction Set Summary,” in this volume. See also: Chapter 3 and
Chapter 4 of Intel® 64 and IA-32 Architectures Software Developer’s Manual,
Volumes 2A & 2B. The following is a summary of special uses:
• EAX — Accumulator for operands and results data
• EBX — Pointer to data in the DS segment
• ECX — Counter for string and loop operations
• EDX — I/O pointer
• ESI — Pointer to data in the segment pointed to by the DS register; source
pointer for string operations
• EDI — Pointer to data (or destination) in the segment pointed to by the ES
register; destination pointer for string operations
• ESP — Stack pointer (in the SS segment)
• EBP — Pointer to data on the stack (in the SS segment)
As shown in Figure 3-5, the lower 16 bits of the general-purpose registers map
directly to the register set found in the 8086 and Intel 286 processors and can be
referenced with the names AX, BX, CX, DX, BP, SI, DI, and SP. Each of the lower two
bytes of the EAX, EBX, ECX, and EDX registers can be referenced by the names AH,
BH, CH, and DH (high bytes) and AL, BL, CL, and DL (low bytes).
2012-03-04 10:53
