http://www.mouseos.com/win64/registers.html
Seems UEFI using rcx, rdx, r8, r9, r10, r11, r12 to store argv
下面是摘自 MSDN 的文章，在 Win64 下的 registers 用途
|
Register
|
Status
|
Use
|
| RAX | Volatile | Return value register |
| RCX | Volatile | First integer argument |
| RDX | Volatile | Second integer argument |
| R8 | Volatile | Third integer argument |
| R9 | Volatile | Fourth integer argument |
| R10:R11 | Volatile | Must be preserved as needed by caller; used in syscall/sysret instructions |
| R12:R15 | Nonvolatile | Must be preserved by callee |
| RDI | Nonvolatile | Must be preserved by callee |
| RSI | Nonvolatile | Must be preserved by callee |
| RBX | Nonvolatile | Must be preserved by callee |
| RBP | Nonvolatile | May be used as a frame pointer; must be preserved by callee |
| RSP | Nonvolatile | Stack pointer |
| XMM0 | Volatile | First FP argument |
| XMM1 | Volatile | Second FP argument |
| XMM2 | Volatile | Third FP argument |
| XMM3 | Volatile | Fourth FP argument |
| XMM4:XMM5 | Volatile | Must be preserved as needed by caller |
| XMM6:XMM15 | Nonvolatile | Must be preserved as needed by callee. |
1. 传递参数
在 Win64 里使用下面寄存器来传递参数：
- rcx - 第 1 个参数
- rdx - 第 2 个参数
- r8 - 第 3 个参数
- r9 - 第 4 个参数
其它多出来的参数通过 stack 传递。
使用下面寄存器来传递浮数数：
- xmm0 - 第 1 个参数
- xmm1 - 第 2 个参数
- xmm2 - 第 3 个参数
- xmm3 - 第 4 个参数