From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44214) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VtNbD-0000Q4-TT for qemu-devel@nongnu.org; Wed, 18 Dec 2013 15:20:16 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VtNb5-0003Ph-GV for qemu-devel@nongnu.org; Wed, 18 Dec 2013 15:20:07 -0500 From: Tom Musta Date: Wed, 18 Dec 2013 14:19:02 -0600 Message-Id: <1387397961-4894-4-git-send-email-tommusta@gmail.com> In-Reply-To: <1387397961-4894-1-git-send-email-tommusta@gmail.com> References: <1387397961-4894-1-git-send-email-tommusta@gmail.com> Subject: [Qemu-devel] [V4 PATCH 03/22] softfloat: Fix float64_to_uint64_round_to_zero List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Tom Musta , qemu-ppc@nongnu.org The float64_to_uint64_round_to_zero routine is incorrect. For example, the following test pattern: 46697351FF4AEC29 / 0x1.97351ff4aec29p+103 currently produces 8000000000000000 instead of FFFFFFFFFFFFFFFF. This patch re-implements the routine to temporarily force the rounding mode and use the float64_to_uint64 routine. This contribution can be licensed under either the softfloat-2a or -2b license. Signed-off-by: Tom Musta --- fpu/softfloat.c | 12 +++++------- 1 files changed, 5 insertions(+), 7 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 1ff59d0..1b614ae 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -6675,13 +6675,11 @@ uint64_t float64_to_uint64(float64 a STATUS_PARAM) uint64_t float64_to_uint64_round_to_zero (float64 a STATUS_PARAM) { - int64_t v; - - v = float64_val(int64_to_float64(INT64_MIN STATUS_VAR)); - v += float64_val(a); - v = float64_to_int64_round_to_zero(make_float64(v) STATUS_VAR); - - return v - INT64_MIN; + signed char current_rounding_mode = STATUS(float_rounding_mode); + set_float_rounding_mode(float_round_to_zero STATUS_VAR); + int64_t v = float64_to_uint64(a STATUS_VAR); + set_float_rounding_mode(current_rounding_mode STATUS_VAR); + return v; } #define COMPARE(s, nan_exp) \ -- 1.7.1