zlib: Optimize inffast even more
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From: Andrew Morton on 11 Nov 2009 18:30 On Mon, 9 Nov 2009 11:22:16 +0100 Joakim Tjernlund <Joakim.Tjernlund(a)transmode.se> wrote: > This improves zlib: Optimize inffast when copying direct from output > and gives another 3-4% improvement for my MPC8321 target. > Does not need CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS, > uses get_unaligned() but only in one place. > The copy loop just above this one can also use this > optimization, but I havn't done so as I have not tested if it > is a win there too. > > Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund(a)transmode.se> > --- > > Someone with a little endian target should test too. eh? That requires a PC. Can't you test it?? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: roel kluin on 11 Nov 2009 18:50 On Mon, Nov 9, 2009 at 11:22 AM, Joakim Tjernlund <Joakim.Tjernlund(a)transmode.se> wrote: > This improves zlib: Optimize inffast when copying direct from output > and gives another 3-4% improvement for my MPC8321 target. > Does not need CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS, > uses get_unaligned() but only in one place. > The copy loop just above this one can also use this > optimization, but I havn't done so as I have not tested if it > is a win there too. > > Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund(a)transmode.se> > --- > @@ -240,52 +243,49 @@ void inflate_fast(z_streamp strm, unsigned start) > } > else { > from = out - dist; /* copy direct from output */ > -#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS > /* minimum length is three */ > if (dist > 2 ) { > - unsigned short *sout = (unsigned short *)(out - OFF); > - unsigned short *sfrom = (unsigned short *)(from - OFF); > - unsigned long loops = len >> 1; > + unsigned short *sout; > + unsigned short *sfrom; > + unsigned long loops; > > + /* Align out addr, only sfrom might be unaligned */ > + if (!((long)(out - 1 + OFF)) & 1) { I think this is wrong did you mean if (!((long)(out - 1 + OFF) & 1)) > + PUP(out) = PUP(from); > + len--; > + } > + sout = (unsigned short *)(out - OFF); > + sfrom = (unsigned short *)(from - OFF); > + loops = len >> 1; > do > - PUP(sout) = PUP(sfrom); > + PUP(sout) = UP_UNALIGNED(sfrom); > while (--loops); > out = (unsigned char *)sout + OFF; > from = (unsigned char *)sfrom + OFF; > if (len & 1) > PUP(out) = PUP(from); > - } else if (dist == 2) { > - unsigned short *sout = (unsigned short *)(out - OFF); > + } else { /* dist == 1 or dist == 2 */ > + unsigned short *sout; > unsigned short pat16; > - unsigned long loops = len >> 1; > + unsigned long loops; > > + /* Align out addr */ > + if (!((long)(out - 1 + OFF)) & 1) { and if (!((long)(out - 1 + OFF) & 1)) > + PUP(out) = PUP(from); > + len--; > + } > + sout = (unsigned short *)(out - OFF); > pat16 = *(sout-2+2*OFF); > + if (dist == 1) > + pat16 = (pat16 & 0xff) | ((pat16 & 0xff ) << 8); > + loops = len >> 1; > do > PUP(sout) = pat16; > while (--loops); > out = (unsigned char *)sout + OFF; > if (len & 1) > PUP(out) = PUP(from); > - } else { > - unsigned char pat8 = *(out - 1 + OFF); > - > - do { > - PUP(out) = pat8; > - } while (--len); > } > -#else > - do { /* minimum length is three */ > - PUP(out) = PUP(from); > - PUP(out) = PUP(from); > - PUP(out) = PUP(from); > - len -= 3; > - } while (len > 2); > - if (len) { > - PUP(out) = PUP(from); > - if (len > 1) > - PUP(out) = PUP(from); > - } > -#endif > } > } > else if ((op & 64) == 0) { /* 2nd level distance code */ > -- > 1.6.4.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo(a)vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >
From: Joakim Tjernlund on 12 Nov 2009 02:30 roel kluin <roel.kluin(a)gmail.com> wrote on 12/11/2009 00:46:41: > > On Mon, Nov 9, 2009 at 11:22 AM, Joakim Tjernlund > <Joakim.Tjernlund(a)transmode.se> wrote: > > This improves zlib: Optimize inffast when copying direct from output > > and gives another 3-4% improvement for my MPC8321 target. > > Does not need CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS, > > uses get_unaligned() but only in one place. > > The copy loop just above this one can also use this > > optimization, but I havn't done so as I have not tested if it > > is a win there too. > > > > Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund(a)transmode.se> > > --- > > > > @@ -240,52 +243,49 @@ void inflate_fast(z_streamp strm, unsigned start) > > � � � � � � � � } > > � � � � � � � � else { > > � � � � � � � � � � from = out - dist; � � � � �/* copy direct from output */ > > -#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS > > � � � � � � � � � � /* minimum length is three */ > > � � � � � � � � � �if (dist > 2 ) { > > - � � � � � � � � � � � unsigned short *sout = (unsigned short *)(out - OFF); > > - � � � � � � � � � � � unsigned short *sfrom = (unsigned short *)(from - OFF); > > - � � � � � � � � � � � unsigned long loops = len >> 1; > > + � � � � � � � � � � � unsigned short *sout; > > + � � � � � � � � � � � unsigned short *sfrom; > > + � � � � � � � � � � � unsigned long loops; > > > > + � � � � � � � � � � � /* Align out addr, only sfrom might be unaligned */ > > + � � � � � � � � � � � if (!((long)(out - 1 + OFF)) & 1) { > > I think this is wrong > > did you mean > > if (!((long)(out - 1 + OFF) & 1)) Yes, will fix and send out a new patch with cleanups and fixes for CPUs that cannot do unaligned accesses. Thanks Jocke -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Joakim Tjernlund on 12 Nov 2009 04:00
Andrew Morton <akpm(a)linux-foundation.org> wrote on 12/11/2009 00:24:45: > > On Mon, 9 Nov 2009 11:22:16 +0100 > Joakim Tjernlund <Joakim.Tjernlund(a)transmode.se> wrote: > > > This improves zlib: Optimize inffast when copying direct from output > > and gives another 3-4% improvement for my MPC8321 target. > > Does not need CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS, > > uses get_unaligned() but only in one place. > > The copy loop just above this one can also use this > > optimization, but I havn't done so as I have not tested if it > > is a win there too. > > > > Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund(a)transmode.se> > > --- > > > > Someone with a little endian target should test too. > > eh? That requires a PC. Can't you test it?? It needs something that actually uses the inflate too on that PC and I don't have that handy. Anyhow, I downloaded zip and made the changes and tested a little, found a problem. Will resend a new patch with everything in it soon. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |