From patchwork Fri Jun 5 18:59:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Myers X-Patchwork-Id: 281241 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 95C47C433DF for ; Fri, 5 Jun 2020 19:02:05 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 6ACF32077D for ; Fri, 5 Jun 2020 19:02:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6ACF32077D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codesourcery.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:46540 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jhHbQ-0000xi-F6 for qemu-devel@archiver.kernel.org; Fri, 05 Jun 2020 15:02:04 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58188) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jhHZG-00078r-1j for qemu-devel@nongnu.org; Fri, 05 Jun 2020 14:59:50 -0400 Received: from esa4.mentor.iphmx.com ([68.232.137.252]:33932) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jhHZE-0006dV-4I for qemu-devel@nongnu.org; Fri, 05 Jun 2020 14:59:49 -0400 IronPort-SDR: PNCzEkExifI0E5ZgJJk48ARcyoDe38aMDKvp0yI0GhzOK2iB862q7a58/ZSzGkz1uuYPzItN4j 7VtWehj5cY5cZlkj6LTEetfsFVZt0rIgKrDt4db2Tv86NUIdi8yaLywzf2eqbgI8VyLTDmO2B4 5KeU/+H+KI6btnjVQtEojfEUkbD5Zy/nD0XIQT5JOkyV/4G1eMaoNkN30B8iF/0Hv+63zX5+po zcCeCbXkF/v/ELs5nk6NCpyVOtT7zuxCG+IkuFIFPYuIAOF3hkuP4tOXvm6n9FHp8VJ+Y0LfVJ 1Nw= X-IronPort-AV: E=Sophos;i="5.73,477,1583222400"; d="scan'208";a="49633014" Received: from orw-gwy-01-in.mentorg.com ([192.94.38.165]) by esa4.mentor.iphmx.com with ESMTP; 05 Jun 2020 10:59:45 -0800 IronPort-SDR: 0CKygn2+BMp+qFux50QRvAri70GpQKg/2zWcYNRoOeRy7DMP6kjMXwrkiZUWXPHDs5enix2j1I g2IuRyfmuvJWRKF/ToJeQ/qFTr7XuZ3PRnnwBF5sTlBNtTRVdx5GBPMIo3U3PONCN5AbwCeH1j VebSrLivS76sWu8I8bx2OTgUmjNr5x61NWBo0fF889vrCEHJabEOhuz2CR5irIdJrmJ+PfwzUc i13VbZ8lY9+BzafgYit+VO+bLgGB/cJ/lq5u+9joxZ/e0czhp/8f9ToDSrbTB06QYa2PHCskuN YbQ= Date: Fri, 5 Jun 2020 18:59:39 +0000 From: Joseph Myers X-X-Sender: jsm28@digraph.polyomino.org.uk To: , , , , , , , Subject: [PATCH 1/7] softfloat: merge floatx80_mod and floatx80_rem In-Reply-To: Message-ID: References: User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 X-Originating-IP: [137.202.0.90] X-ClientProxiedBy: SVR-IES-MBX-07.mgc.mentorg.com (139.181.222.7) To svr-ies-mbx-02.mgc.mentorg.com (139.181.222.2) Received-SPF: pass client-ip=68.232.137.252; envelope-from=joseph_myers@mentor.com; helo=esa4.mentor.iphmx.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/05 14:59:46 X-ACL-Warn: Detected OS = FreeBSD 9.x or newer [fuzzy] X-Spam_score_int: -39 X-Spam_score: -4.0 X-Spam_bar: ---- X-Spam_report: (-4.0 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 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" The m68k-specific softfloat code includes a function floatx80_mod that is extremely similar to floatx80_rem, but computing the remainder based on truncating the quotient toward zero rather than rounding it to nearest integer. This is also useful for emulating the x87 fprem and fprem1 instructions. Change the floatx80_rem implementation into floatx80_modrem that can perform either operation, with both floatx80_rem and floatx80_mod as thin wrappers available for all targets. There does not appear to be any use for the _mod operation for other floating-point formats in QEMU (the only other architectures using _rem at all are linux-user/arm/nwfpe, for FPA emulation, and openrisc, for instructions that have been removed in the latest version of the architecture), so no change is made to the code for other formats. Signed-off-by: Joseph Myers --- fpu/softfloat.c | 49 ++++++++++++++++++------ include/fpu/softfloat.h | 2 + target/m68k/softfloat.c | 83 ----------------------------------------- target/m68k/softfloat.h | 1 - 4 files changed, 40 insertions(+), 95 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 6c8f2d597a..7b1ce7664f 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -5682,10 +5682,13 @@ floatx80 floatx80_div(floatx80 a, floatx80 b, float_status *status) /*---------------------------------------------------------------------------- | Returns the remainder of the extended double-precision floating-point value | `a' with respect to the corresponding value `b'. The operation is performed -| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. +| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic, +| if 'mod' is false; if 'mod' is true, return the remainder based on truncating +| the quotient toward zero instead. *----------------------------------------------------------------------------*/ -floatx80 floatx80_rem(floatx80 a, floatx80 b, float_status *status) +floatx80 floatx80_modrem(floatx80 a, floatx80 b, bool mod, + float_status *status) { bool aSign, zSign; int32_t aExp, bExp, expDiff; @@ -5731,7 +5734,7 @@ floatx80 floatx80_rem(floatx80 a, floatx80 b, float_status *status) expDiff = aExp - bExp; aSig1 = 0; if ( expDiff < 0 ) { - if ( expDiff < -1 ) return a; + if ( mod || expDiff < -1 ) return a; shift128Right( aSig0, 0, 1, &aSig0, &aSig1 ); expDiff = 0; } @@ -5763,14 +5766,16 @@ floatx80 floatx80_rem(floatx80 a, floatx80 b, float_status *status) term1 = 0; term0 = bSig; } - sub128( term0, term1, aSig0, aSig1, &alternateASig0, &alternateASig1 ); - if ( lt128( alternateASig0, alternateASig1, aSig0, aSig1 ) - || ( eq128( alternateASig0, alternateASig1, aSig0, aSig1 ) - && ( q & 1 ) ) - ) { - aSig0 = alternateASig0; - aSig1 = alternateASig1; - zSign = ! zSign; + if (!mod) { + sub128( term0, term1, aSig0, aSig1, &alternateASig0, &alternateASig1 ); + if ( lt128( alternateASig0, alternateASig1, aSig0, aSig1 ) + || ( eq128( alternateASig0, alternateASig1, aSig0, aSig1 ) + && ( q & 1 ) ) + ) { + aSig0 = alternateASig0; + aSig1 = alternateASig1; + zSign = ! zSign; + } } return normalizeRoundAndPackFloatx80( @@ -5778,6 +5783,28 @@ floatx80 floatx80_rem(floatx80 a, floatx80 b, float_status *status) } +/*---------------------------------------------------------------------------- +| Returns the remainder of the extended double-precision floating-point value +| `a' with respect to the corresponding value `b'. The operation is performed +| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. +*----------------------------------------------------------------------------*/ + +floatx80 floatx80_rem(floatx80 a, floatx80 b, float_status *status) +{ + return floatx80_modrem(a, b, false, status); +} + +/*---------------------------------------------------------------------------- +| Returns the remainder of the extended double-precision floating-point value +| `a' with respect to the corresponding value `b', with the quotient truncated +| toward zero. +*----------------------------------------------------------------------------*/ + +floatx80 floatx80_mod(floatx80 a, floatx80 b, float_status *status) +{ + return floatx80_modrem(a, b, true, status); +} + /*---------------------------------------------------------------------------- | Returns the square root of the extended double-precision floating-point | value `a'. The operation is performed according to the IEC/IEEE Standard diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h index 16ca697a73..bff6934d09 100644 --- a/include/fpu/softfloat.h +++ b/include/fpu/softfloat.h @@ -687,6 +687,8 @@ floatx80 floatx80_add(floatx80, floatx80, float_status *status); floatx80 floatx80_sub(floatx80, floatx80, float_status *status); floatx80 floatx80_mul(floatx80, floatx80, float_status *status); floatx80 floatx80_div(floatx80, floatx80, float_status *status); +floatx80 floatx80_modrem(floatx80, floatx80, bool, float_status *status); +floatx80 floatx80_mod(floatx80, floatx80, float_status *status); floatx80 floatx80_rem(floatx80, floatx80, float_status *status); floatx80 floatx80_sqrt(floatx80, float_status *status); FloatRelation floatx80_compare(floatx80, floatx80, float_status *status); diff --git a/target/m68k/softfloat.c b/target/m68k/softfloat.c index 9f120cf15e..b6d0ed7acf 100644 --- a/target/m68k/softfloat.c +++ b/target/m68k/softfloat.c @@ -42,89 +42,6 @@ static floatx80 propagateFloatx80NaNOneArg(floatx80 a, float_status *status) return a; } -/* - * Returns the modulo remainder of the extended double-precision floating-point - * value `a' with respect to the corresponding value `b'. - */ - -floatx80 floatx80_mod(floatx80 a, floatx80 b, float_status *status) -{ - bool aSign, zSign; - int32_t aExp, bExp, expDiff; - uint64_t aSig0, aSig1, bSig; - uint64_t qTemp, term0, term1; - - aSig0 = extractFloatx80Frac(a); - aExp = extractFloatx80Exp(a); - aSign = extractFloatx80Sign(a); - bSig = extractFloatx80Frac(b); - bExp = extractFloatx80Exp(b); - - if (aExp == 0x7FFF) { - if ((uint64_t) (aSig0 << 1) - || ((bExp == 0x7FFF) && (uint64_t) (bSig << 1))) { - return propagateFloatx80NaN(a, b, status); - } - goto invalid; - } - if (bExp == 0x7FFF) { - if ((uint64_t) (bSig << 1)) { - return propagateFloatx80NaN(a, b, status); - } - return a; - } - if (bExp == 0) { - if (bSig == 0) { - invalid: - float_raise(float_flag_invalid, status); - return floatx80_default_nan(status); - } - normalizeFloatx80Subnormal(bSig, &bExp, &bSig); - } - if (aExp == 0) { - if ((uint64_t) (aSig0 << 1) == 0) { - return a; - } - normalizeFloatx80Subnormal(aSig0, &aExp, &aSig0); - } - bSig |= UINT64_C(0x8000000000000000); - zSign = aSign; - expDiff = aExp - bExp; - aSig1 = 0; - if (expDiff < 0) { - return a; - } - qTemp = (bSig <= aSig0); - if (qTemp) { - aSig0 -= bSig; - } - expDiff -= 64; - while (0 < expDiff) { - qTemp = estimateDiv128To64(aSig0, aSig1, bSig); - qTemp = (2 < qTemp) ? qTemp - 2 : 0; - mul64To128(bSig, qTemp, &term0, &term1); - sub128(aSig0, aSig1, term0, term1, &aSig0, &aSig1); - shortShift128Left(aSig0, aSig1, 62, &aSig0, &aSig1); - expDiff -= 62; - } - expDiff += 64; - if (0 < expDiff) { - qTemp = estimateDiv128To64(aSig0, aSig1, bSig); - qTemp = (2 < qTemp) ? qTemp - 2 : 0; - qTemp >>= 64 - expDiff; - mul64To128(bSig, qTemp << (64 - expDiff), &term0, &term1); - sub128(aSig0, aSig1, term0, term1, &aSig0, &aSig1); - shortShift128Left(0, bSig, 64 - expDiff, &term0, &term1); - while (le128(term0, term1, aSig0, aSig1)) { - ++qTemp; - sub128(aSig0, aSig1, term0, term1, &aSig0, &aSig1); - } - } - return - normalizeRoundAndPackFloatx80( - 80, zSign, bExp + expDiff, aSig0, aSig1, status); -} - /* * Returns the mantissa of the extended double-precision floating-point * value `a'. diff --git a/target/m68k/softfloat.h b/target/m68k/softfloat.h index 365ef6ac7a..4bb9567134 100644 --- a/target/m68k/softfloat.h +++ b/target/m68k/softfloat.h @@ -23,7 +23,6 @@ #define TARGET_M68K_SOFTFLOAT_H #include "fpu/softfloat.h" -floatx80 floatx80_mod(floatx80 a, floatx80 b, float_status *status); floatx80 floatx80_getman(floatx80 a, float_status *status); floatx80 floatx80_getexp(floatx80 a, float_status *status); floatx80 floatx80_scale(floatx80 a, floatx80 b, float_status *status);