From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35324) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bzcFD-0008G4-Tt for qemu-devel@nongnu.org; Thu, 27 Oct 2016 00:24:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bzcFC-0007Bt-QZ for qemu-devel@nongnu.org; Thu, 27 Oct 2016 00:24:47 -0400 Date: Thu, 27 Oct 2016 12:47:34 +1100 From: David Gibson Message-ID: <20161027014734.GD19918@umbus.fritz.box> References: <1477487938-23921-1-git-send-email-joserz@linux.vnet.ibm.com> <1477487938-23921-5-git-send-email-joserz@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="lc9FT7cWel8HagAv" Content-Disposition: inline In-Reply-To: <1477487938-23921-5-git-send-email-joserz@linux.vnet.ibm.com> Subject: Re: [Qemu-devel] [PATCH] 4/4] target-ppc: Implement bcdctz. instruction List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jose Ricardo Ziviani Cc: qemu-ppc@nongnu.org, qemu-devel@nongnu.org, nikunj@linux.vnet.ibm.com, bharata@linux.vnet.ibm.com --lc9FT7cWel8HagAv Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Oct 26, 2016 at 11:18:58AM -0200, Jose Ricardo Ziviani wrote: > bcdctz. converts from BCD to Zoned numeric format. Zoned format uses > a byte to represent a digit where the most significant nibble is 0x3 > or 0xf, depending on the preferred signal. >=20 > Signed-off-by: Jose Ricardo Ziviani > --- > target-ppc/helper.h | 1 + > target-ppc/int_helper.c | 54 +++++++++++++++++++++++++++++++= ++++++ > target-ppc/translate/vmx-impl.inc.c | 7 +++-- > 3 files changed, 60 insertions(+), 2 deletions(-) >=20 > diff --git a/target-ppc/helper.h b/target-ppc/helper.h > index f460635..3b928b8 100644 > --- a/target-ppc/helper.h > +++ b/target-ppc/helper.h > @@ -372,6 +372,7 @@ DEF_HELPER_4(bcdsub, i32, avr, avr, avr, i32) > DEF_HELPER_3(bcdcfn, i32, avr, avr, i32) > DEF_HELPER_2(bcdctn, i32, avr, avr) > DEF_HELPER_3(bcdcfz, i32, avr, avr, i32) > +DEF_HELPER_3(bcdctz, i32, avr, avr, i32) > =20 > DEF_HELPER_2(xsadddp, void, env, i32) > DEF_HELPER_2(xssubdp, void, env, i32) > diff --git a/target-ppc/int_helper.c b/target-ppc/int_helper.c > index 8cbbdfc..e0a84bb 100644 > --- a/target-ppc/int_helper.c > +++ b/target-ppc/int_helper.c > @@ -2768,6 +2768,60 @@ uint32_t helper_bcdcfz(ppc_avr_t *r, ppc_avr_t *b,= uint32_t ps) > *r =3D ret; > return cr; > } > + > +uint32_t helper_bcdctz(ppc_avr_t *r, ppc_avr_t *b, uint32_t ps) > +{ > + int i; > + int j; > + int cr =3D 0; > + int invalid =3D 0; > + uint8_t digit =3D 0; > + int sgnb =3D bcd_get_sgn(b); > + int zone_lead =3D (ps) ? 0xF0 : 0x30; > + ppc_avr_t ret =3D { .u64 =3D { 0, 0 } }; > + > + int eq_flag =3D (b->u64[HI_IDX] =3D=3D 0) && ((b->u64[LO_IDX] >> 4) = =3D=3D 0); > + int ox_flag =3D (b->u64[HI_IDX] !=3D 0); This doesn't look right. The zoned format can accomodate 16 digits. The low word of the packed format can accomodate 15 digits + sign. So it should be possible to convert a packed for with a value in the low nibble of the upper word. > + for (i =3D 31, j =3D 16; i > 1; i -=3D 2, j--) { Again not seeing any point for the reverse order. > + digit =3D get_nibble(b, j); > + ret.u8[BCD_DIG_BYTE(i)] =3D zone_lead + digit; > + > + if (unlikely(digit > 9)) { > + invalid =3D 1; > + } > + } > + > + if (unlikely(!sgnb)) { > + sgnb =3D (!get_nibble(b, 0)) ? 1 : -1; > + } Doesn't bcd_get_sgn() returning 0 indicate a badly encoded sign point. In which case you should set invalid, rather than making up a sign according to this apparently arbitrary scheme. > + > + if (ps) { > + bcd_put_digit(&ret, (sgnb =3D=3D 1) ? 0xC : 0xD, 1); > + } else { > + bcd_put_digit(&ret, (sgnb =3D=3D 1) ? 0x3 : 0x7, 1); > + } > + bcd_put_digit(&ret, get_nibble(b, 1), 0); > + > + if (!eq_flag) { > + cr =3D (sgnb =3D=3D 1) ? 1 << CRF_GT : 1 << CRF_LT; > + } else { > + cr =3D 1 << CRF_EQ; > + } > + > + if (ox_flag) { > + cr |=3D 1 << CRF_SO; > + } > + > + if (unlikely(invalid)) { > + cr =3D 1 << CRF_SO; > + } > + > + *r =3D ret; > + > + return cr; > +} > + > void helper_vsbox(ppc_avr_t *r, ppc_avr_t *a) > { > int i; > diff --git a/target-ppc/translate/vmx-impl.inc.c b/target-ppc/translate/v= mx-impl.inc.c > index 9192f8f..62c44f0 100644 > --- a/target-ppc/translate/vmx-impl.inc.c > +++ b/target-ppc/translate/vmx-impl.inc.c > @@ -918,6 +918,7 @@ GEN_BCD(bcdsub) > GEN_BCD2(bcdcfn) > GEN_BCD3(bcdctn) > GEN_BCD2(bcdcfz) > +GEN_BCD2(bcdctz) > =20 > static void gen_xpnd04_1(DisasContext *ctx) > { > @@ -927,7 +928,8 @@ static void gen_xpnd04_1(DisasContext *ctx) > case 2: > break; /* bcdcfsq. */ > case 4: > - break; /* bcdctz. */ > + gen_bcdctz(ctx); > + break; > case 5: > gen_bcdctn(ctx); > break; > @@ -952,7 +954,8 @@ static void gen_xpnd04_2(DisasContext *ctx) > case 2: > break; /* bcdcfsq. */ > case 4: > - break; /* bcdctz. */ > + gen_bcdctz(ctx); > + break; > case 6: > gen_bcdcfz(ctx); > break; --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --lc9FT7cWel8HagAv Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJYEVyzAAoJEGw4ysog2bOSeEIQAKt7Yy2aNFngbSnMU6IPwbAL o3M590z3MiAKf+wR2KcoOirnjw90GHKtBn3oRBSIVcUJTK5Ff6m9SombPXgkIc18 foj+ie3E1C9JAjrRrW3mWt567AZ6wAdcq9alGF6P9pCNY22tn3+7ZstMM/UU/b7W xgmIy6pzloaG/5FuAk+9/CoGQZYYTlEOp6xb+v5FVJnFFIlYFyC8TPoSCN/dqO8M oupjKchjm8EhA/WQRZVOYYhj0EAnfMq+xtKYpr3HVH1M0NMg7WmiERLD9fAqp+ZJ cYdVk4wWLTs9t2kTxG9cExb7YqReypTLg6Xs+k+nTwM8BOiakPnTWoaBXSl3shgH ZHKbCsCGrRnWjpO7jVYedPL34GCd07bajQ6kAHZp+5dY+3nPH5hb6rBIAKpFwHV7 gHp7WnM+qjtig0vFAJCVUnk+Y7gfwfBPDIG9VabbAQuu/haUAyhOUHJFrip3EkLl UFdUpurqSllk6RJn7Qg2JezFNWC+gcWXLIbC+BmuOAkFAw7jSD5YzPSpcmEkPY9Y 6UrcWTNo4wzHn6r699UUEteyHXtI8Qz9yb5dy/yBMKqYQu1eQBcu1/fjNmTthHMF dg/fSm3Oy/yBB00Ko8bQEGABDQuPpHegxDi3hR4/g4AqUyaeMqxArD3eWQ3un2LQ mWE+Xj/05WLHeUQAd9bE =gHZM -----END PGP SIGNATURE----- --lc9FT7cWel8HagAv--