From patchwork Mon Oct 21 08:57:13 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11201575 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D608113BD for ; Mon, 21 Oct 2019 09:01:08 +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 AB5322089C for ; Mon, 21 Oct 2019 09:01:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="isEtRAxo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AB5322089C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:36104 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iMTYp-0005Ye-0L for patchwork-qemu-devel@patchwork.kernel.org; Mon, 21 Oct 2019 05:01:07 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:59335) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iMTVR-0001KT-55 for qemu-devel@nongnu.org; Mon, 21 Oct 2019 04:57:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iMTVQ-0008HM-0x for qemu-devel@nongnu.org; Mon, 21 Oct 2019 04:57:37 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:21672) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iMTVN-0008Fs-Nu for qemu-devel@nongnu.org; Mon, 21 Oct 2019 04:57:34 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1571648251; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=UpzX3vb9RgNNLYiM/JvDGiNB0vNs3Bk5YnPik6Epjvk=; b=isEtRAxo4KMFzEdJq6tz24JaGzU/ptwoGqmxcW7KMeAabBVM0tQs5n5kZ6lreJS5040Ez+ kxIGUILL74sETYhG6BwGMakpcCvDzIpQ6gUeP22zJxYXkUY4+r9TqZJeOK5wwH7tv2NSrW o4ZJBjkKQtQyLSNjTh4R2cZqPggYXPc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-9-FpeKXJQZO1OL8ZIwYpVLmA-1; Mon, 21 Oct 2019 04:57:30 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1E349107AD31; Mon, 21 Oct 2019 08:57:29 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-198.ams2.redhat.com [10.36.116.198]) by smtp.corp.redhat.com (Postfix) with ESMTP id 95E955D6B0; Mon, 21 Oct 2019 08:57:27 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v2 4/6] s390x/tcg: Fix VECTOR SUBTRACT COMPUTE BORROW INDICATION Date: Mon, 21 Oct 2019 10:57:13 +0200 Message-Id: <20191021085715.3797-5-david@redhat.com> In-Reply-To: <20191021085715.3797-1-david@redhat.com> References: <20191021085715.3797-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-MC-Unique: FpeKXJQZO1OL8ZIwYpVLmA-1 X-Mimecast-Spam-Score: 0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.81 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: , Cc: Thomas Huth , David Hildenbrand , Ivan Warren , Cornelia Huck , Richard Henderson , qemu-s390x@nongnu.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" Looks like my idea of what a "borrow" is was wrong. The PoP says: "If the resulting subtraction results in a carry out of bit zero, a value of one is placed in the corresponding element of the first operand; otherwise, a value of zero is placed in the corresponding element" As clarified by Richard, all we have to do is invert the result. Fixes: 1ee2d7ba72f6 ("s390x/tcg: Implement VECTOR SUBTRACT COMPUTE BORROW INDICATION") Signed-off-by: David Hildenbrand Reviewed-by: Richard Henderson --- target/s390x/translate_vx.inc.c | 7 ++++--- target/s390x/vec_int_helper.c | 2 +- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/target/s390x/translate_vx.inc.c b/target/s390x/translate_vx.inc.c index 5ce7bfb0af..6032021d82 100644 --- a/target/s390x/translate_vx.inc.c +++ b/target/s390x/translate_vx.inc.c @@ -2132,12 +2132,12 @@ static DisasJumpType op_vs(DisasContext *s, DisasOps *o) static void gen_scbi_i32(TCGv_i32 d, TCGv_i32 a, TCGv_i32 b) { - tcg_gen_setcond_i32(TCG_COND_LTU, d, a, b); + tcg_gen_setcond_i32(TCG_COND_GEU, d, a, b); } static void gen_scbi_i64(TCGv_i64 d, TCGv_i64 a, TCGv_i64 b) { - tcg_gen_setcond_i64(TCG_COND_LTU, d, a, b); + tcg_gen_setcond_i64(TCG_COND_GEU, d, a, b); } static void gen_scbi2_i64(TCGv_i64 dl, TCGv_i64 dh, TCGv_i64 al, @@ -2151,7 +2151,8 @@ static void gen_scbi2_i64(TCGv_i64 dl, TCGv_i64 dh, TCGv_i64 al, tcg_gen_andi_i64(th, th, 1); tcg_gen_sub2_i64(tl, th, ah, zero, th, zero); tcg_gen_sub2_i64(tl, th, tl, th, bh, zero); - tcg_gen_andi_i64(dl, th, 1); + /* "invert" the result: -1 -> 0; 0 -> 1 */ + tcg_gen_addi_i64(dl, th, 1); tcg_gen_mov_i64(dh, zero); tcg_temp_free_i64(th); diff --git a/target/s390x/vec_int_helper.c b/target/s390x/vec_int_helper.c index d38405848f..0d6bc13dd6 100644 --- a/target/s390x/vec_int_helper.c +++ b/target/s390x/vec_int_helper.c @@ -593,7 +593,7 @@ void HELPER(gvec_vscbi##BITS)(void *v1, const void *v2, const void *v3, \ const uint##BITS##_t a = s390_vec_read_element##BITS(v2, i); \ const uint##BITS##_t b = s390_vec_read_element##BITS(v3, i); \ \ - s390_vec_write_element##BITS(v1, i, a < b); \ + s390_vec_write_element##BITS(v1, i, a >= b); \ } \ } DEF_VSCBI(8)