问题描述
我通过一些教程上的http://www.ibm.com/developerworks/linux/library/l-gas-nasm/index.html以自己熟悉的x86 / x64操作系统。本教程code编译和使用提供code，它使用AT＆功放没有打嗝运行; T语法：
I'm working through some of the tutorials on http://www.ibm.com/developerworks/linux/library/l-gas-nasm/index.html to familiarize myself with x86/x64. This tutorial code compiles and runs without a hiccup using the provided code, which uses AT&T syntax:
.global main
.text
main: # This is called by C library's startup code
mov $message, %rdi # First integer (or pointer) parameter in %edi
call puts # puts("Hello, World")
ret # Return to C library code
message:
.asciz "Hello, World" # asciz puts a 0x00 byte at the end
然而，当我转换这个code到Intel语法，我得到一个分段错误错误。
However, when I convert this code to Intel syntax, I get a "Segmentation fault" error.
.intel_syntax noprefix
.global main
.text
main: # This is called by C library's startup code
mov rdi, message # First integer (or pointer) parameter in %edi
call puts # puts("Hello, World")
ret # Return to C library code
message:
.asciz "Hello, World" # asciz puts a 0x00 byte at the end
我不熟悉的x86，所以也许我失去了一些东西。任何想法？
I'm not familiar with x86, so perhaps I'm missing something. Any ideas?
推荐答案
在AT＆amp; T公司的语法， MOV $消息，％RDI 的 $ 手段的直接的，这意味着地址的的消息的
In AT&T syntax, mov $message, %rdi, the $ means immediate, meaning the address of message.
在GAS的Intel语法， MOV RDI，消息表示绝对寻址，在的消息的意思是内容即可。要获得的的消息的，您需要提供偏移关键字的实际地址： MOV RDI，偏移信息。
In GAS's Intel syntax, mov rdi, message means absolute addressing, meaning the content at message. To get the actual address of message, you need to supply the offset keyword: mov rdi, offset message.
两个二进制Disassebly显示区别：
Disassebly of the two binaries shows the difference:
AT＆amp; T公司：
AT&T:
0000000000000000 <main>:
0: 48 c7 c7 00 00 00 00 mov $0x0,%rdi
英特尔：
0000000000000000 <main>:
0: 48 8b 3c 25 00 00 00 mov 0x0,%rdi
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