From patchwork Mon Mar 14 15:37:13 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Maydell X-Patchwork-Id: 86765 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 71BCEB6F81 for ; Tue, 15 Mar 2011 02:37:48 +1100 (EST) Received: from localhost ([127.0.0.1]:53824 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Pz9q4-0007xX-Bh for incoming@patchwork.ozlabs.org; Mon, 14 Mar 2011 11:37:44 -0400 Received: from [140.186.70.92] (port=46784 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Pz9pe-0007wy-Py for qemu-devel@nongnu.org; Mon, 14 Mar 2011 11:37:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Pz9pc-0007Hd-7T for qemu-devel@nongnu.org; Mon, 14 Mar 2011 11:37:17 -0400 Received: from mnementh.archaic.org.uk ([81.2.115.146]:33873) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Pz9pc-0007HE-0K for qemu-devel@nongnu.org; Mon, 14 Mar 2011 11:37:16 -0400 Received: from pm215 by mnementh.archaic.org.uk with local (Exim 4.72) (envelope-from ) id 1Pz9pZ-00073v-OC; Mon, 14 Mar 2011 15:37:13 +0000 From: Peter Maydell To: qemu-devel@nongnu.org Date: Mon, 14 Mar 2011 15:37:13 +0000 Message-Id: <1300117033-27120-3-git-send-email-peter.maydell@linaro.org> X-Mailer: git-send-email 1.7.2.3 In-Reply-To: <1300117033-27120-1-git-send-email-peter.maydell@linaro.org> References: <1300117033-27120-1-git-send-email-peter.maydell@linaro.org> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 2) X-Received-From: 81.2.115.146 Cc: patches@linaro.org Subject: [Qemu-devel] [PATCH v2 2/2] target-arm: use make_float32() to make constant floats for VRSQRTS X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org The preferred way to create a constant floating point value is to use make_float32() rather than doing a runtime int32_to_float32(). Convert the code in the VRSQRTS helper to work this way. Signed-off-by: Peter Maydell --- target-arm/helper.c | 11 +++++------ 1 files changed, 5 insertions(+), 6 deletions(-) diff --git a/target-arm/helper.c b/target-arm/helper.c index c01a5a2..0dd2549 100644 --- a/target-arm/helper.c +++ b/target-arm/helper.c @@ -2708,6 +2708,8 @@ uint32_t HELPER(vfp_fcvt_f32_to_f16)(float32 a, CPUState *env) } #define float32_two make_float32(0x40000000) +#define float32_three make_float32(0x40400000) +#define float32_one_point_five make_float32(0x3fc00000) float32 HELPER(recps_f32)(float32 a, float32 b, CPUState *env) { @@ -2722,16 +2724,13 @@ float32 HELPER(recps_f32)(float32 a, float32 b, CPUState *env) float32 HELPER(rsqrts_f32)(float32 a, float32 b, CPUState *env) { float_status *s = &env->vfp.standard_fp_status; - float32 two = int32_to_float32(2, s); - float32 three = int32_to_float32(3, s); float32 product; if ((float32_is_infinity(a) && float32_is_zero_or_denormal(b)) || (float32_is_infinity(b) && float32_is_zero_or_denormal(a))) { - product = float32_zero; - } else { - product = float32_mul(a, b, s); + return float32_one_point_five; } - return float32_div(float32_sub(three, product, s), two, s); + product = float32_mul(a, b, s); + return float32_div(float32_sub(float32_three, product, s), float32_two, s); } /* NEON helpers. */