From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DD3EBC6FA99 for ; Tue, 7 Mar 2023 21:52:44 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pZfE6-0001Ml-EE; Tue, 07 Mar 2023 16:52:06 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pZfE4-0001Ly-7M; Tue, 07 Mar 2023 16:52:04 -0500 Received: from mail-oi1-x236.google.com ([2607:f8b0:4864:20::236]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1pZfE2-0005Xz-C7; Tue, 07 Mar 2023 16:52:03 -0500 Received: by mail-oi1-x236.google.com with SMTP id s41so10740630oiw.13; Tue, 07 Mar 2023 13:52:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1678225920; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=6PD57IzsERyb0ZaPhEhMgWoh9I40jDB0YKs1BENhvqc=; b=ogZ5KK9QXTxAdsN3haxh/LfXjkUWZz1a29UQJ+3vYkj4Rl+Ovawa055/+fmNVSl2zd zxf++lssrXYCBrAHXivIG88NnC2k2FuLySin2atUVrgexehjMyAEFSREKBiUbmLlpUJW 3NShsSVRQxVitXgIrX7NLBv0A568VDZ/0DeUScJcbSBwanH5DpRy5cRxXFsdVr2BNpie tFKzTCT3JtMnOTxR8D0JVz21rAdVSPtbgf0+N2zQy6cx0hAADKFfCbHt4FH36l5kf7On /f2feU57lXyyPGGCO37HAA+u22L+LSK27EreHdDSg5Dkg1oFs/qUfcs380YV/5bxPJ0T HYXA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678225920; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=6PD57IzsERyb0ZaPhEhMgWoh9I40jDB0YKs1BENhvqc=; b=PbI1WB+TsODPCuOKhzCSLDwyh8HDk7nUyTkAHGQaJ5yF7j3RfKyYcu9wJVvmTdvM4H 0CzIRU1zv2bUjKbcOEvEHabPuvnUNKUMVmRkFatKC3ABWY3Nn+wqagNS7lM80db6ELqZ c1wKl/1sX/YIK3qfsVyd5yBeS4uphgS92Ry3mEyY4iH2rX/7VKinaapNC5tW1aLAlCVK YoCdEktdKzQJkT8f7DXT415k1wBGQbod4A2foSlHaX6PBqxtiYyUoQMjgyVK2F+Ticwz DrGWd3uR1PLuPcNUvd9BiY9guWve3XkCVJc83eDcVFl9WIzrbkQkt97YmzdnT7oe3A6I R/8A== X-Gm-Message-State: AO0yUKVQxJwqa0Q+Ke+OXlOv+v2ik3cRb4QPtOL2yFPLh616OcMztE0Y tqwFW8pTjBl6yJgmA7OBIeM= X-Google-Smtp-Source: AK7set+DiY6He2YHqk1rFOOqnmY14H/AQiyvRpU8uhEmCNvKDT+l8fnBWoCQy2c4VG/OHZwq8I378g== X-Received: by 2002:a54:4789:0:b0:378:2762:2770 with SMTP id o9-20020a544789000000b0037827622770mr7584976oic.15.1678225920534; Tue, 07 Mar 2023 13:52:00 -0800 (PST) Received: from [192.168.68.107] ([177.189.53.31]) by smtp.gmail.com with ESMTPSA id r8-20020a0568080aa800b00383cc29d6b2sm5558590oij.51.2023.03.07.13.51.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 07 Mar 2023 13:52:00 -0800 (PST) Message-ID: <4951ac67-2bfd-b6db-4cb6-94d7ead96325@gmail.com> Date: Tue, 7 Mar 2023 18:51:56 -0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.8.0 Subject: Re: [PATCH v2 20/25] target/ppc: Rewrite trans_ADDG6S Content-Language: en-US To: Richard Henderson , qemu-devel@nongnu.org Cc: =?UTF-8?Q?C=c3=a9dric_Le_Goater?= , David Gibson , Greg Kurz , qemu-ppc@nongnu.org References: <20230307183503.2512684-1-richard.henderson@linaro.org> <20230307183503.2512684-21-richard.henderson@linaro.org> From: Daniel Henrique Barboza In-Reply-To: <20230307183503.2512684-21-richard.henderson@linaro.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2607:f8b0:4864:20::236; envelope-from=danielhb413@gmail.com; helo=mail-oi1-x236.google.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_ENVFROM_END_DIGIT=0.25, FREEMAIL_FROM=0.001, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 3/7/23 15:34, Richard Henderson wrote: > Compute all carry bits in parallel instead of a loop. > > Signed-off-by: Richard Henderson > --- Hmmmm the function was added by 6addef4d27268 9 months ago. All tcg ops you used here were available back then. I guess this existing implementation was an oversight on our end. Reviewed-by: Daniel Henrique Barboza > Cc: Daniel Henrique Barboza > Cc: Cédric Le Goater > Cc: David Gibson > Cc: Greg Kurz > Cc: qemu-ppc@nongnu.org > --- > target/ppc/translate/fixedpoint-impl.c.inc | 44 +++++++++++----------- > 1 file changed, 23 insertions(+), 21 deletions(-) > > diff --git a/target/ppc/translate/fixedpoint-impl.c.inc b/target/ppc/translate/fixedpoint-impl.c.inc > index 20ea484c3d..02d86b77a8 100644 > --- a/target/ppc/translate/fixedpoint-impl.c.inc > +++ b/target/ppc/translate/fixedpoint-impl.c.inc > @@ -484,33 +484,35 @@ static bool trans_PEXTD(DisasContext *ctx, arg_X *a) > > static bool trans_ADDG6S(DisasContext *ctx, arg_X *a) > { > - const uint64_t carry_bits = 0x1111111111111111ULL; > - TCGv t0, t1, carry, zero = tcg_constant_tl(0); > + const target_ulong carry_bits = (target_ulong)-1 / 0xf; > + TCGv in1, in2, carryl, carryh, tmp; > + TCGv zero = tcg_constant_tl(0); > > REQUIRE_INSNS_FLAGS2(ctx, BCDA_ISA206); > > - t0 = tcg_temp_new(); > - t1 = tcg_const_tl(0); > - carry = tcg_const_tl(0); > + in1 = cpu_gpr[a->ra]; > + in2 = cpu_gpr[a->rb]; > + tmp = tcg_temp_new(); > + carryl = tcg_temp_new(); > + carryh = tcg_temp_new(); > > - for (int i = 0; i < 16; i++) { > - tcg_gen_shri_tl(t0, cpu_gpr[a->ra], i * 4); > - tcg_gen_andi_tl(t0, t0, 0xf); > - tcg_gen_add_tl(t1, t1, t0); > + /* Addition with carry. */ > + tcg_gen_add2_tl(carryl, carryh, in1, zero, in2, zero); > + /* Addition without carry. */ > + tcg_gen_xor_tl(tmp, in1, in2); > + /* Difference between the two is carry in to each bit. */ > + tcg_gen_xor_tl(carryl, carryl, tmp); > > - tcg_gen_shri_tl(t0, cpu_gpr[a->rb], i * 4); > - tcg_gen_andi_tl(t0, t0, 0xf); > - tcg_gen_add_tl(t1, t1, t0); > + /* > + * The carry-out that we're looking for is the carry-in to > + * the next nibble. Shift the double-word down one nibble, > + * which puts all of the bits back into one word. > + */ > + tcg_gen_extract2_tl(carryl, carryl, carryh, 4); > > - tcg_gen_andi_tl(t1, t1, 0x10); > - tcg_gen_setcond_tl(TCG_COND_NE, t1, t1, zero); > - > - tcg_gen_shli_tl(t0, t1, i * 4); > - tcg_gen_or_tl(carry, carry, t0); > - } > - > - tcg_gen_xori_tl(carry, carry, (target_long)carry_bits); > - tcg_gen_muli_tl(cpu_gpr[a->rt], carry, 6); > + /* Invert, isolate the carry bits, and produce 6's. */ > + tcg_gen_andc_tl(carryl, tcg_constant_tl(carry_bits), carryl); > + tcg_gen_muli_tl(cpu_gpr[a->rt], carryl, 6); > return true; > } >