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

From: H. Peter Anvin
Date: Thu Apr 23 2009 - 18:13:19 EST


Joe Damato wrote:

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.


Not unless it can be proven those calls are in non-performance-critical contexts. That's a lot of work to go through, though.

-hpa

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