From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:40615) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QIKtw-0000Yv-7p for qemu-devel@nongnu.org; Fri, 06 May 2011 09:17:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QIKtv-0007T4-Ax for qemu-devel@nongnu.org; Fri, 06 May 2011 09:17:00 -0400 Received: from mnementh.archaic.org.uk ([81.2.115.146]:36404) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QIKtv-0007Sc-1f for qemu-devel@nongnu.org; Fri, 06 May 2011 09:16:59 -0400 From: Peter Maydell Date: Fri, 6 May 2011 13:48:09 +0100 Message-Id: <1304686095-30265-2-git-send-email-peter.maydell@linaro.org> In-Reply-To: <1304686095-30265-1-git-send-email-peter.maydell@linaro.org> References: <1304686095-30265-1-git-send-email-peter.maydell@linaro.org> Subject: [Qemu-devel] [PATCH 1/7] target-arm: Don't set FP exceptions in recip, recip_sqrt estimate fns List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: patches@linaro.org The functions which do the core estimation algorithms for the VRSQRTE and VRECPE instructions should not set floating point exception flags, so use a local fp status for doing these calculations. Signed-off-by: Peter Maydell --- target-arm/helper.c | 12 ++++++++++-- 1 files changed, 10 insertions(+), 2 deletions(-) diff --git a/target-arm/helper.c b/target-arm/helper.c index 62ae72e..5ff6a9b 100644 --- a/target-arm/helper.c +++ b/target-arm/helper.c @@ -2749,7 +2749,11 @@ float32 HELPER(rsqrts_f32)(float32 a, float32 b, CPUState *env) */ static float64 recip_estimate(float64 a, CPUState *env) { - float_status *s = &env->vfp.standard_fp_status; + /* These calculations mustn't set any fp exception flags, + * so we use a local copy of the fp_status. + */ + float_status dummy_status = env->vfp.standard_fp_status; + float_status *s = &dummy_status; /* q = (int)(a * 512.0) */ float64 q = float64_mul(float64_512, a, s); int64_t q_int = float64_to_int64_round_to_zero(q, s); @@ -2812,7 +2816,11 @@ float32 HELPER(recpe_f32)(float32 a, CPUState *env) */ static float64 recip_sqrt_estimate(float64 a, CPUState *env) { - float_status *s = &env->vfp.standard_fp_status; + /* These calculations mustn't set any fp exception flags, + * so we use a local copy of the fp_status. + */ + float_status dummy_status = env->vfp.standard_fp_status; + float_status *s = &dummy_status; float64 q; int64_t q_int; -- 1.7.1