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SubjectRe: [RFC PATCH (take #2)] i386: kill CONFIG_REGPARM completely
linux-os (Dick Johnson) wrote:

>On ix86 there are not enough registers to pass a significant parameter
>list all in registers! Like when you are printk()ing a dotted-quad IP
>address, etc. Registers ESI, EDI, and EBX are precious, that leaves
>EAX, ECX, EDX and possibly EBP for only 4 parameters. You need 5
>for the dotted quad IP address. If the compiler were to use the
>precious registers, the contents need to be saved on the stack.
>That negates any advantage to passing parameters in registers.
>
>
I had the impression that REGPARM in i386 only passed the
first three arguments in registers, putting any further
paramters on the stack?

Ought to help for all those 3-argument or less functions.

Helge Hafting
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