Messages in this thread | | | Date | Wed, 22 Aug 2012 20:14:00 -0700 | From | "H. Peter Anvin" <> | Subject | Re: [PATCH 74/74] lto, workaround: Mark do_futex noinline to prevent clobbering ebp |
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On 08/22/2012 07:29 PM, Andi Kleen wrote: > How about just use register arguments for the first three arguments. > This should work for the syscalls at least (may be too risky for all > other asm entry points)
Well, it's just an effort to convert each one in turn...
> And for syscalls with more than three generate a stub that saves on the stack > explicitely. This could be done using the new fancy SYSCALL definition macros > (except that arch/x86 would need to start using them too in its own code)
I don't think there is any point. Just push the six potential arguments to the stack and be done with it.
> Or is there some subtle reason with syscall restart and updated args > that prevents it? > > Perhaps newer gcc can do regparm(X), X > 3 too, may be worth trying.
No, there is no such ABI defined.
> Don't have time to look into this currently though.
Always the problem.
-hpa
-- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.
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