From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41853) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cgUHd-00011H-0n for qemu-devel@nongnu.org; Wed, 22 Feb 2017 05:36:29 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cgUHZ-0001G2-UG for qemu-devel@nongnu.org; Wed, 22 Feb 2017 05:36:29 -0500 Sender: Richard Henderson References: <1487755788-16415-1-git-send-email-nikunj@linux.vnet.ibm.com> <1487755788-16415-6-git-send-email-nikunj@linux.vnet.ibm.com> From: Richard Henderson Message-ID: <64842dbd-8b97-0ccd-28d8-89f73a625b44@twiddle.net> Date: Wed, 22 Feb 2017 21:36:16 +1100 MIME-Version: 1.0 In-Reply-To: <1487755788-16415-6-git-send-email-nikunj@linux.vnet.ibm.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2 05/11] target/ppc: update ca32 in arithmetic substract List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Nikunj A Dadhania , qemu-ppc@nongnu.org, david@gibson.dropbear.id.au Cc: qemu-devel@nongnu.org, bharata@linux.vnet.ibm.com On 02/22/2017 08:29 PM, Nikunj A Dadhania wrote: > Signed-off-by: Nikunj A Dadhania > --- > target/ppc/translate.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/target/ppc/translate.c b/target/ppc/translate.c > index b589d09..184d10f 100644 > --- a/target/ppc/translate.c > +++ b/target/ppc/translate.c > @@ -827,7 +827,15 @@ static inline void gen_op_arith_compute_ca32(DisasContext *ctx, > } > > t0 = tcg_temp_new(); > - tcg_gen_xor_tl(t0, arg0, arg1); > + if (!add_ca && sub) { I think checking add_ca is wrong. And note that it is otherwise unused. > + /* Invert arg0 before xor as in the !add_ca case, > + * we do not get inverse of arg0 > + */ > + tcg_gen_not_tl(t0, arg0); > + tcg_gen_xor_tl(t0, t0, arg1); > + } else { > + tcg_gen_xor_tl(t0, arg0, arg1); > + } > tcg_gen_xor_tl(t0, t0, res); > tcg_gen_extract_tl(cpu_ca32, t0, 32, 1); > tcg_temp_free(t0); > @@ -1382,11 +1390,13 @@ static inline void gen_op_arith_subf(DisasContext *ctx, TCGv ret, TCGv arg1, > zero = tcg_const_tl(0); > tcg_gen_add2_tl(t0, cpu_ca, arg2, zero, cpu_ca, zero); > tcg_gen_add2_tl(t0, cpu_ca, t0, cpu_ca, inv1, zero); > + gen_op_arith_compute_ca32(ctx, t0, inv1, arg2, add_ca, 1); The last parameter here should be 0. > tcg_temp_free(zero); > tcg_temp_free(inv1); > } else { > tcg_gen_setcond_tl(TCG_COND_GEU, cpu_ca, arg2, arg1); > tcg_gen_sub_tl(t0, arg2, arg1); > + gen_op_arith_compute_ca32(ctx, t0, arg1, arg2, add_ca, 1); > } > } else if (add_ca) { > /* Since we're ignoring carry-out, we can simplify the > r~