From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40135) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1byjEI-0002Zy-HP for qemu-devel@nongnu.org; Mon, 24 Oct 2016 13:40:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1byjEH-0005XM-Q2 for qemu-devel@nongnu.org; Mon, 24 Oct 2016 13:40:10 -0400 Received: from mail-pf0-x243.google.com ([2607:f8b0:400e:c00::243]:34198) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1byjEH-0005W8-HF for qemu-devel@nongnu.org; Mon, 24 Oct 2016 13:40:09 -0400 Received: by mail-pf0-x243.google.com with SMTP id 128so17138225pfz.1 for ; Mon, 24 Oct 2016 10:40:09 -0700 (PDT) Sender: Richard Henderson From: Richard Henderson Date: Mon, 24 Oct 2016 10:39:34 -0700 Message-Id: <1477330788-14996-24-git-send-email-rth@twiddle.net> In-Reply-To: <1477330788-14996-1-git-send-email-rth@twiddle.net> References: <1477330788-14996-1-git-send-email-rth@twiddle.net> Subject: [Qemu-devel] [PATCH v8 23/37] target-i386: emulate LOCK'ed NEG using cmpxchg helper List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: peter.maydell@linaro.org, cota@braap.org, alex.bennee@linaro.org From: "Emilio G. Cota" [rth: Move redundant qemu_load out of cmpxchg loop.] Signed-off-by: Emilio G. Cota Message-Id: <1467054136-10430-16-git-send-email-cota@braap.org> Signed-off-by: Richard Henderson --- target-i386/translate.c | 38 ++++++++++++++++++++++++++++++++++---- 1 file changed, 34 insertions(+), 4 deletions(-) diff --git a/target-i386/translate.c b/target-i386/translate.c index 6d71564..d2edbd9 100644 --- a/target-i386/translate.c +++ b/target-i386/translate.c @@ -4712,11 +4712,41 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s, } break; case 3: /* neg */ - tcg_gen_neg_tl(cpu_T0, cpu_T0); - if (mod != 3) { - gen_op_st_v(s, ot, cpu_T0, cpu_A0); + if (s->prefix & PREFIX_LOCK) { + TCGLabel *label1; + TCGv a0, t0, t1, t2; + + if (mod == 3) { + goto illegal_op; + } + a0 = tcg_temp_local_new(); + t0 = tcg_temp_local_new(); + label1 = gen_new_label(); + + tcg_gen_mov_tl(a0, cpu_A0); + tcg_gen_mov_tl(t0, cpu_T0); + + gen_set_label(label1); + t1 = tcg_temp_new(); + t2 = tcg_temp_new(); + tcg_gen_mov_tl(t2, t0); + tcg_gen_neg_tl(t1, t0); + tcg_gen_atomic_cmpxchg_tl(t0, a0, t0, t1, + s->mem_index, ot | MO_LE); + tcg_temp_free(t1); + tcg_gen_brcond_tl(TCG_COND_NE, t0, t2, label1); + + tcg_temp_free(t2); + tcg_temp_free(a0); + tcg_gen_mov_tl(cpu_T0, t0); + tcg_temp_free(t0); } else { - gen_op_mov_reg_v(ot, rm, cpu_T0); + tcg_gen_neg_tl(cpu_T0, cpu_T0); + if (mod != 3) { + gen_op_st_v(s, ot, cpu_T0, cpu_A0); + } else { + gen_op_mov_reg_v(ot, rm, cpu_T0); + } } gen_op_update_neg_cc(); set_cc_op(s, CC_OP_SUBB + ot); -- 2.7.4