On Tue, Oct 13, 2009 at 5:18 PM, Bingfeng Mei <b...@broadcom.com> wrote: > > >> -----Original Message----- >> From: Richard Guenther [mailto:richard.guent...@gmail.com] >> Sent: 13 October 2009 16:15 >> To: Bingfeng Mei >> Cc: gcc@gcc.gnu.org >> Subject: Re: LTO question >> >> On Tue, Oct 13, 2009 at 2:47 PM, Bingfeng Mei >> <b...@broadcom.com> wrote: >> > Hello, >> > I just had the first taste with the latest LTO merge on our port. >> > Compiler is configured with LTO enabled and built correctly. >> > I tried the following example: >> > >> > a.c >> > extern void foo(int); >> > int main() >> > { foo(20); >> > return 1; >> > } >> > >> > b.c >> > #include <stdio.h> >> > void foo(int c) >> > { >> > printf("Hello world: %d\n", c); >> > } >> > >> > compiled with: >> > firepath-elf-gcc -flto a.c b.c -save-temps -O2 >> > >> > I expected that foo should be inlined into main, but not. >> Both functions >> > of main and foo are present in a.s, while b.s contains the >> LTO code. >> > >> > Did I miss something here? Are there new hooks I should >> specify or tune for >> > LTO? I checked the up-to-date internal manual and found nothing. >> >> non-inline declared functions are inlined at -O2 only if doing so >> does not increase program size. Use -O3 or -finline-functions. > > But the function is only called once here. It should always decrease size > unless > my cost function is terribly wrong. I will check how other targets such as > x86 do here.
The function is still exported if you do not use -fwhole-program. Richard.
