Is it possible to restore the original name if the copy propagation is not profitable and doesn't go ahead?
> -----Original Message----- > From: Richard Guenther [mailto:richard.guent...@gmail.com] > Sent: 16 June 2009 13:56 > To: Bingfeng Mei > Cc: gcc@gcc.gnu.org > Subject: Re: Questionable function renaming > > On Tue, Jun 16, 2009 at 2:23 PM, Bingfeng > Mei<b...@broadcom.com> wrote: > > Hello, > > > > I came across a function renaming issue in GCC 4.4. > > > > ~/work/install-x86/bin/gcc -Wall -Winline -O3 -g > -D_FILE_OFFSET_BITS=64 -save-temps -c bzip2.c -fdump-tree-all > > > > > > Function saveInputFileMetaInfo is renamed to T.251 after > ipa passes, which are not dumped into intermediate files. So > compare bzip2.c.038t.release_ssa and bzip2.c.049t.copyrename2 file, > > > > ;; Function saveInputFileMetaInfo (saveInputFileMetaInfo) > > > > Released 3 names, 50.00% > > saveInputFileMetaInfo (Char * srcName) > > { > > IntNative retVal; > > > > <bb 2>: > > retVal_4 = __xstat (1, srcName_1(D), &fileMetaInfo); > > if (retVal_4 != 0) > > goto <bb 3>; > > else > > goto <bb 4>; > > > > <bb 3>: > > ioError (); > > > > <bb 4>: > > return; > > > > } > > > > becomes > > > > ;; Function T.251 (T.251) > > > > T.251 () > > { > > IntNative retVal; > > > > <bb 2>: > > retVal_1 = __xstat (1, &inName, &fileMetaInfo); > > if (retVal_1 != 0) > > goto <bb 3>; > > else > > goto <bb 4>; > > > > <bb 3>: > > ioError (); > > > > <bb 4>: > > return; > > > > } > > > > The renamed function stays afterwards. My understanding is > that ipa-cp pass did copy-propagation of the original > function but still somehow create a clone as suggested > bzip2.c.203t.statistics. > > > > bzip2.c.203t.statistics:35 copyprop "Copies propagated" > "saveInputFileMetaInfo" 1 > > bzip2.c.203t.statistics:35 copyprop "Statements deleted" > "saveInputFileMetaInfo" 3 > > > > This seems unnecessary and causes trouble in our > profiling/debugging tools. I could diable this by using > -fno-ipa-cp. But is there any better way? Thanks in advance > > It constant propagated &inName here (probably not very profitable > as no further optimization is performed on the body) and removed > the then unused parameter. > > Any better way to do what? > > Richard. > > > Cheers, > > Bingfeng Mei > > > > Boradcom UK > >
