[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v1] Implement support for IEEE 754-201x minimumN
|
From: |
Michael Clark |
|
Subject: |
Re: [Qemu-devel] [PATCH v1] Implement support for IEEE 754-201x minimumNumber/maximumNumber |
|
Date: |
Thu, 8 Feb 2018 14:37:39 +1300 |
I've included this patch in the RISC-V patch series just submitted.
The change is enclosed within a simple conditional so there is no risk of
affecting any other ports.
There was one line whitespace fix to the pre-existing code however it fell
nicely within the diff hunk so I included the fix.
On Thu, Feb 8, 2018 at 12:43 PM, Michael Clark <address@hidden> wrote:
> QEMU currently implements IEEE 754-2008 minNum/maxNum. This patch adds
> support for IEEE 754-201x minimumNumber/maximumNumber which is required
> by the RISC-V port.
>
> minNum(x, y) is defined as
> - min(x, y) if neither is NaN
> - if one of x and y is a number and one is qNaN, return the number
> - if both are qNaN, or either is sNaN, return NaN
>
> minimumNumber(x, y) is defined as
> - min(x, y) if neither is NaN
> - if one of x and y is a number and one is qNaN or sNaN, return the number
> - if both are NaN, return the number
>
> Both functions signal the invalid exception on sNaN inputs.
>
> Signed-off-by: Michael Clark <address@hidden>
> ---
> fpu/softfloat.c | 41 +++++++++++++++++++++++++++++++++++------
> include/fpu/softfloat.h | 4 ++++
> 2 files changed, 39 insertions(+), 6 deletions(-)
>
> diff --git a/fpu/softfloat.c b/fpu/softfloat.c
> index 433c5da..5793cc9 100644
> --- a/fpu/softfloat.c
> +++ b/fpu/softfloat.c
> @@ -7675,6 +7675,9 @@ int float128_compare_quiet(float128 a, float128 b,
> float_status *status)
> * minnummag() and maxnummag() functions correspond to minNumMag()
> * and minNumMag() from the IEEE-754 2008.
> */
> +
> +enum { ieee2008 = 1, ieee201x = 2 };
> +
> #define MINMAX(s) \
> static inline float ## s float ## s ## _minmax(float ## s a, float ## s
> b, \
> int ismin, int isieee, \
> @@ -7687,12 +7690,26 @@ static inline float ## s float ## s ##
> _minmax(float ## s a, float ## s b, \
> b = float ## s ## _squash_input_denormal(b, status); \
> if (float ## s ## _is_any_nan(a) || \
> float ## s ## _is_any_nan(b)) { \
> - if (isieee) { \
> + if (isieee == ieee2008) { \
> if (float ## s ## _is_quiet_nan(a, status) && \
> !float ## s ##_is_any_nan(b)) { \
> return b; \
> } else if (float ## s ## _is_quiet_nan(b, status) && \
> - !float ## s ## _is_any_nan(a)) { \
> + !float ## s ## _is_any_nan(a)) { \
> + return a; \
> + } \
> + } else if (isieee == ieee201x) { \
> + if (float ## s ## _is_any_nan(a) && \
> + !float ## s ##_is_any_nan(b)) { \
> + if (!float ## s ## _is_quiet_nan(a, status)) { \
> + float_raise(float_flag_invalid, status); \
> + } \
> + return b; \
> + } else if (float ## s ## _is_any_nan(b) && \
> + !float ## s ## _is_any_nan(a)) { \
> + if (!float ## s ## _is_quiet_nan(b, status)) { \
> + float_raise(float_flag_invalid, status); \
> + } \
> return a; \
> } \
> } \
> @@ -7743,25 +7760,37 @@ float ## s float ## s ## _max(float ## s a, float
> ## s b, \
> float ## s float ## s ## _minnum(float ## s a, float ## s b, \
> float_status *status) \
> { \
> - return float ## s ## _minmax(a, b, 1, 1, 0, status); \
> + return float ## s ## _minmax(a, b, 1, ieee2008, 0, status); \
> } \
> \
> float ## s float ## s ## _maxnum(float ## s a, float ## s b, \
> float_status *status) \
> { \
> - return float ## s ## _minmax(a, b, 0, 1, 0, status); \
> + return float ## s ## _minmax(a, b, 0, ieee2008, 0, status); \
> +} \
> + \
> +float ## s float ## s ## _minimumnumber(float ## s a, float ## s b, \
> + float_status *status) \
> +{ \
> + return float ## s ## _minmax(a, b, 1, ieee201x, 0, status); \
> +} \
> + \
> +float ## s float ## s ## _maximumnumber(float ## s a, float ## s b, \
> + float_status *status) \
> +{ \
> + return float ## s ## _minmax(a, b, 0, ieee201x, 0, status); \
> } \
> \
> float ## s float ## s ## _minnummag(float ## s a, float ## s b, \
> float_status *status) \
> { \
> - return float ## s ## _minmax(a, b, 1, 1, 1, status); \
> + return float ## s ## _minmax(a, b, 1, ieee2008, 1, status); \
> } \
> \
> float ## s float ## s ## _maxnummag(float ## s a, float ## s b, \
> float_status *status) \
> { \
> - return float ## s ## _minmax(a, b, 0, 1, 1, status); \
> + return float ## s ## _minmax(a, b, 0, ieee2008, 1, status); \
> }
>
> MINMAX(32)
> diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h
> index 0f96a0e..e0d0259 100644
> --- a/include/fpu/softfloat.h
> +++ b/include/fpu/softfloat.h
> @@ -424,6 +424,8 @@ float32 float32_min(float32, float32, float_status
> *status);
> float32 float32_max(float32, float32, float_status *status);
> float32 float32_minnum(float32, float32, float_status *status);
> float32 float32_maxnum(float32, float32, float_status *status);
> +float32 float32_minimumnumber(float32, float32, float_status *status);
> +float32 float32_maximumnumber(float32, float32, float_status *status);
> float32 float32_minnummag(float32, float32, float_status *status);
> float32 float32_maxnummag(float32, float32, float_status *status);
> int float32_is_quiet_nan(float32, float_status *status);
> @@ -536,6 +538,8 @@ float64 float64_min(float64, float64, float_status
> *status);
> float64 float64_max(float64, float64, float_status *status);
> float64 float64_minnum(float64, float64, float_status *status);
> float64 float64_maxnum(float64, float64, float_status *status);
> +float64 float64_minimumnumber(float64, float64, float_status *status);
> +float64 float64_maximumnumber(float64, float64, float_status *status);
> float64 float64_minnummag(float64, float64, float_status *status);
> float64 float64_maxnummag(float64, float64, float_status *status);
> int float64_is_quiet_nan(float64 a, float_status *status);
> --
> 2.7.0
>
>