| Message ID | 55E6FB54.9090800@landley.net (mailing list archive) |
|---|---|
| State | Awaiting Upstream |
| Headers | show |
On Wed, Sep 02, 2015 at 08:36:20AM -0500, Rob Landley wrote: > From: Rob Landley <rob@landley.net> > > The common checksum code uses shld which sh2 hasn't got, so unwind it. > > Note: http://nommu.org/jcore added SHAD and SHLD, and if anybody's > building for an actual sh2 they'll either need gcc 4.7 or earlier or > a fix to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54089 but > when regression testing against the actual historical hardware, > you need this. > > Signed-off-by: Rob Landley <rob@landley.net> > --- > > arch/sh/lib/checksum.S | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/arch/sh/lib/checksum.S b/arch/sh/lib/checksum.S > index 356c8ec..7f0fc6b 100644 > --- a/arch/sh/lib/checksum.S > +++ b/arch/sh/lib/checksum.S > @@ -88,8 +88,9 @@ ENTRY(csum_partial) > 2: > ! buf is 4 byte aligned (len could be 0) > mov r5, r1 > - mov #-5, r0 > - shld r0, r1 > + shlr2 r1 ! mov #-5, r0 > + shlr2 r1 ! shld r0, r1 > + shlr r1 Is this a performance-critical code path (e.g. for networking)? If not, I like your current solution best because it's simple and #ifdef-free. But if it is critical and the shld is faster, perhaps #ifdef for SH3+ would be appropriate, and we could expand to include J2 in the #ifdef with the J2 support patches? Rich -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/sh/lib/checksum.S b/arch/sh/lib/checksum.S index 356c8ec..7f0fc6b 100644 --- a/arch/sh/lib/checksum.S +++ b/arch/sh/lib/checksum.S @@ -88,8 +88,9 @@ ENTRY(csum_partial) 2: ! buf is 4 byte aligned (len could be 0) mov r5, r1 - mov #-5, r0 - shld r0, r1 + shlr2 r1 ! mov #-5, r0 + shlr2 r1 ! shld r0, r1 + shlr r1 tst r1, r1 bt/s 4f ! if it's =0, go to 4f clrt @@ -288,8 +289,9 @@ DST( mov.w r0,@r5 ) addc r0,r7 2: mov r6,r2 - mov #-5,r0 - shld r0,r6 + shlr2 r6 ! mov #-5, r0 + shlr2 r6 ! shld r0, r6 + shlr r6 tst r6,r6 bt/s 2f clrt