From: Peter Maydell <peter.maydell@linaro.org>
To: Tom Musta <tommusta@gmail.com>
Cc: "qemu-ppc@nongnu.org" <qemu-ppc@nongnu.org>,
QEMU Developers <qemu-devel@nongnu.org>
Subject: Re: [Qemu-devel] [V4 PATCH 03/22] softfloat: Fix float64_to_uint64_round_to_zero
Date: Thu, 19 Dec 2013 21:43:42 +0000 [thread overview]
Message-ID: <CAFEAcA8X6AD2vm9u_vqUsJosVbTb4AjEb_+Qd2iVm8HNkps+nw@mail.gmail.com> (raw)
In-Reply-To: <1387397961-4894-4-git-send-email-tommusta@gmail.com>
On 18 December 2013 20:19, Tom Musta <tommusta@gmail.com> wrote:
> 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 <tommusta@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
The other approach would be to make all the conversion
functions explicitly take the rounding mode parameter
(and in some ways that might be closer to the set of
functionality IEE754-2008 describes), but this is a
simple change and saving and restoring rounding mode
is very cheap.
thanks
-- PMM
next prev parent reply other threads:[~2013-12-19 21:44 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-12-18 20:18 [Qemu-devel] [V4 PATCH 00/22] PowerPC VSX Stage 3 Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 01/22] softfloat: Fix float64_to_uint64 Tom Musta
2013-12-19 22:11 ` Peter Maydell
2013-12-20 20:05 ` [Qemu-devel] [Qemu-ppc] " Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 02/22] softfloat: Add float32_to_uint64() Tom Musta
2013-12-19 21:31 ` Peter Maydell
2013-12-20 20:07 ` Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 03/22] softfloat: Fix float64_to_uint64_round_to_zero Tom Musta
2013-12-19 21:43 ` Peter Maydell [this message]
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 04/22] softfloat: Fix float64_to_uint32 Tom Musta
2013-12-19 21:48 ` Peter Maydell
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 05/22] softfloat: Fix float64_to_uint32_round_to_zero Tom Musta
2013-12-19 21:41 ` Peter Maydell
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 06/22] target-ppc: Add set_fprf Argument to fload_invalid_op_excp() Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 07/22] target-ppc: General Support for VSX Helpers Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 08/22] target-ppc: Add VSX ISA2.06 xadd/xsub Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 09/22] target-ppc: Add VSX ISA2.06 xmul Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 10/22] target-ppc: Add VSX ISA2.06 xdiv Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 11/22] target-ppc: Add VSX ISA2.06 xre Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 12/22] target-ppc: Add VSX ISA2.06 xsqrt Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 13/22] target-ppc: Add VSX ISA2.06 xrsqrte Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 14/22] target-ppc: Add VSX ISA2.06 xtdiv Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 15/22] target-ppc: Add VSX ISA2.06 xtsqrt Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 16/22] target-ppc: Add VSX ISA2.06 Multiply Add Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 17/22] target-ppc: Add VSX xscmp*dp Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 18/22] target-ppc: Add VSX xmax/xmin Instructions Tom Musta
2013-12-24 16:23 ` Richard Henderson
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 19/22] target-ppc: Add VSX Vector Compare Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 20/22] target-ppc: Add VSX Floating Point to Floating Point Conversion Instructions Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 21/22] target-ppc: Add VSX ISA2.06 Integer " Tom Musta
2013-12-18 20:19 ` [Qemu-devel] [V4 PATCH 22/22] target-ppc: Add VSX Rounding Instructions Tom Musta
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