Re: [PATCH] X86-32: Let gcc decide whether to inline memcpy was Re: New x86 warning

[Joe Damato]

On Wed, Apr 22, 2009 at 6:48 PM, H. Peter Anvin <hpa@xxxxxxxxx> wrote:
> Joe Damato wrote:
>>
>> I think this patch is great. Perhaps this would be a good time to also
>> clean out memset for x86_32? (If needed, I can start a new email
>> thread with this patch) I've built and booted this on my x86_32
>> hardware.
>>
>
> Under the same conditions, i.e. making sure that with the oldest gcc we
> still care about (3.2) we don't end up uninlining any new cases we
> shouldn't.

Looks like this thread is dead/dying, but figured I should reply with
my test findings. The number of out-of-line calls (as determined by:
make mrproper && make defconfig && make && objdump -d vmlinux | grep
"call.*\<memset" | wc -l))

gcc 4.2.4 - withOUT memset patch: 20
gcc 4.2.4 - with memset patch: 365

gcc 3.4 - withOUT memset patch: 17
gcc 3.4 - with memset patch: 349

I'm guessing this is probably not acceptable, so I won't bother
installing/trying gcc-3.2 unless anyone thinks that a 300+ increase in
out-of-line calls is OK.

Joe
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