本文详细介绍了在程序中如何使用寄存器来传递参数，并解释了独立定义的过程和对象方法之间的区别。对于独立定义的过程和函数，eax、ebx、ecx 和 edx 寄存器分别用于存储第一个参数、数据块地址、第三个参数和第二个参数的值。而对于对象方法，eax 存储父对象的数据块地址，而 ecx 和 edx 则分别用于存储第二个和第一个参数的值。
The registers are set with values before entering the function or procedure. How these are set depends on how the function or procedure was defined. There are two possibilities.
Stand alone, or explicitly defined procedures and functions
On entry,
eax holds the value of the first parameter of the function or procedure if such exists.
ebx holds the address of the data block of the function or procedure. You must be careful when using ebx, for it must hold its initial value whenever you refer to a function or procedure's parameters or data in your assembler code block. Furthermore ebx must hold its initial value when exiting. The Delphi manual actually says don't touch.
ecx holds the value of the third parameter.
edx holds the second parameter value.
On exit,
eax holds the result of the function, or in the case of a procedure, convention states it holds the value of any relevant error code you may define.
ebx must hold its initial value. Failure to ensure this will cause a system crash.
Object method, procedures and functions
On entry,
eax holds the address of the parent object's data block. You don't need to maintain this value, however it is needed whenever you wish to access or change the values of the parent object's fields.
ebx is the same as above.
ecx holds the second parameter value.
edx holds the value of the first parameter.
On exit, the register values are as for a stand alone procedure or function.
注：64位汇编，过程或函数的前面四个传参寄存器变成了：RCX, RDX, R8, R9（或XMM0-XMM3）
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