On Wed, Mar 26, 2014 at 04:49:09PM +0000, Jay Foad wrote: > The emulation for single and double precision multiply accumulate > instructions correctly normalised any denormal values in the operand > registers, but failed to normalise the destination (accumulator) > register. > > This fixes https://bugzilla.kernel.org/show_bug.cgi?id=70501 > > Signed-off-by: Jay Foad <jay.f...@gmail.com>
Reviewed-by: Dave Martin <dave.mar...@arm.com> This appears to be clean and straightforward, so if nobody else has commented on this by the time -rc1 comes out, I suggest you rebase it and send it to the patch system. (See http://www.arm.linux.org.uk/developer/patches/info.php for details -- make sure you read it carefully.) Has this issue been hitting real-world users of the kernel, or is this fixing a latent bug? Cheers ---Dave > --- > arch/arm/vfp/vfpdouble.c | 2 ++ > arch/arm/vfp/vfpsingle.c | 2 ++ > 2 files changed, 4 insertions(+) > > diff --git a/arch/arm/vfp/vfpdouble.c b/arch/arm/vfp/vfpdouble.c > index 6cac43bd1d86..423f56dd4028 100644 > --- a/arch/arm/vfp/vfpdouble.c > +++ b/arch/arm/vfp/vfpdouble.c > @@ -866,6 +866,8 @@ vfp_double_multiply_accumulate(int dd, int dn, int dm, > u32 fpscr, u32 negate, ch > vdp.sign = vfp_sign_negate(vdp.sign); > > vfp_double_unpack(&vdn, vfp_get_double(dd)); > + if (vdn.exponent == 0 && vdn.significand) > + vfp_double_normalise_denormal(&vdn); > if (negate & NEG_SUBTRACT) > vdn.sign = vfp_sign_negate(vdn.sign); > > diff --git a/arch/arm/vfp/vfpsingle.c b/arch/arm/vfp/vfpsingle.c > index b252631b406b..4f96c1617aae 100644 > --- a/arch/arm/vfp/vfpsingle.c > +++ b/arch/arm/vfp/vfpsingle.c > @@ -915,6 +915,8 @@ vfp_single_multiply_accumulate(int sd, int sn, s32 m, u32 > fpscr, u32 negate, cha > v = vfp_get_float(sd); > pr_debug("VFP: s%u = %08x\n", sd, v); > vfp_single_unpack(&vsn, v); > + if (vsn.exponent == 0 && vsn.significand) > + vfp_single_normalise_denormal(&vsn); > if (negate & NEG_SUBTRACT) > vsn.sign = vfp_sign_negate(vsn.sign); > > -- > 1.8.3.2 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-ker...@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
