Commit Graph

32 Commits

Author SHA1 Message Date
Richard Henderson
9343c88444 softfloat: Use FloatRelation within partsN_compare
As the return type is FloatRelation, it's clearer to
use the type for 'cmp' within the function.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220401132240.79730-3-richard.henderson@linaro.org>
2022-04-26 20:01:55 -07:00
Richard Henderson
e706d4455b softfloat: Add flag specific to signaling nans
PowerPC has this flag, and it's easier to compute it here
than after the fact.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-8-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2021-12-17 17:57:14 +01:00
Richard Henderson
81254b02eb softfloat: Add flag specific to convert non-nan to int
PowerPC has this flag, and it's easier to compute it here
than after the fact.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-7-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2021-12-17 17:57:14 +01:00
Richard Henderson
f8718aab89 softfloat: Add flag specific to sqrt(-x)
PowerPC has this flag, and it's easier to compute it here
than after the fact.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-6-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2021-12-17 17:57:14 +01:00
Richard Henderson
10cc964030 softfloat: Add flags specific to Inf / Inf and 0 / 0
PowerPC has these flags, and it's easier to compute them here
than after the fact.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-5-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2021-12-17 17:57:14 +01:00
Richard Henderson
bead3c9b0f softfloat: Add flag specific to Inf * 0
PowerPC has this flag, and it's easier to compute it here
than after the fact.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-4-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2021-12-17 17:57:14 +01:00
Richard Henderson
ba11446c40 softfloat: Add flag specific to Inf - Inf
PowerPC has this flag, and it's easier to compute it here
than after the fact.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-3-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2021-12-17 17:57:14 +01:00
Chih-Min Chao
0e9030376e softfloat: add APIs to handle alternative sNaN propagation for fmax/fmin
For "fmax/fmin ft0, ft1, ft2" and if one of the inputs is sNaN,

  The original logic:
    Return NaN and set invalid flag if ft1 == sNaN || ft2 == sNan.

  The alternative path:
    Set invalid flag if ft1 == sNaN || ft2 == sNaN.
    Return NaN only if ft1 == NaN && ft2 == NaN.

The IEEE 754 spec allows both implementation and some architecture such
as riscv choose different defintions in two spec versions.
(riscv-spec-v2.2 use original version, riscv-spec-20191213 changes to
 alternative)

Signed-off-by: Chih-Min Chao <chihmin.chao@sifive.com>
Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211021160847.2748577-2-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2021-10-29 16:55:45 +10:00
Richard Henderson
feaf2e9c06 softfloat: Convert modrem operations to FloatParts
Rename to parts$N_modrem.  This was the last use of a lot
of the legacy infrastructure, so remove it as required.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 14:09:02 -07:00
Richard Henderson
2fa3546c8f softfloat: Move floatN_log2 to softfloat-parts.c.inc
Rename to parts$N_log2.  Though this is partly a ruse, since I do not
believe the code will succeed for float128 without work.  Which is ok
for now, because we do not need this for more than float32 and float64.

Since berkeley-testfloat-3 doesn't support log2, compare float64_log2
vs the system log2.  Fix the errors for inputs near 1.0:

test: 3ff00000000000b0  +0x1.00000000000b0p+0
  sf: 3d2fa00000000000  +0x1.fa00000000000p-45
libm: 3d2fbd422b1bd36f  +0x1.fbd422b1bd36fp-45
Error in fraction: 32170028290927 ulp

test: 3feec24f6770b100  +0x1.ec24f6770b100p-1
  sf: bfad3740d13c9ec0  -0x1.d3740d13c9ec0p-5
libm: bfad3740d13c9e98  -0x1.d3740d13c9e98p-5
Error in fraction: 40 ulp

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 14:09:02 -07:00
Richard Henderson
98b3cff753 softfloat: Adjust parts_uncanon_normal for floatx80
With floatx80_precision_x, the rounding happens across
the break between words.  Notice this case with

  frac_lsb = round_mask + 1 -> 0

and check the bits in frac_hi as needed.

In addition, since frac_shift == 0, we won't implicitly clear
round_mask via the right-shift, so explicitly clear those bits.
This fixes rounding for floatx80_precision_[sd].

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 14:09:02 -07:00
Richard Henderson
d6e1f0cd59 softfloat: Reduce FloatFmt
Remove frac_lsb, frac_lsbm1, roundeven_mask.  Compute
these from round_mask in parts$N_uncanon_normal.

With floatx80, round_mask will not be tied to frac_shift.
Everything else is easily computable.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 14:04:02 -07:00
Richard Henderson
25fdedf0d3 softfloat: Split out parts_uncanon_normal
We will need to treat the non-normal cases of floatx80 specially,
so split out the normal case that we can reuse.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 14:04:02 -07:00
Richard Henderson
9261b245f0 softfloat: Move sqrt_float to softfloat-parts.c.inc
Rename to parts$N_sqrt.
Reimplement float128_sqrt with FloatParts128.

Reimplement with the inverse sqrt newton-raphson algorithm from musl.
This is significantly faster than even the berkeley sqrt n-r algorithm,
because it does not use division instructions, only multiplication.

Ordinarily, changing algorithms at the same time as migrating code is
a bad idea, but this is the only way I found that didn't break one of
the routines at the same time.

Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 13:59:34 -07:00
Richard Henderson
39626b0ce8 softfloat: Move scalbn_decomposed to softfloat-parts.c.inc
Rename to parts$N_scalbn.
Reimplement float128_scalbn with FloatParts128.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 13:59:34 -07:00
Richard Henderson
6eb169b89a softfloat: Move compare_floats to softfloat-parts.c.inc
Rename to parts$N_compare.  Rename all of the intermediate
functions to ftype_do_compare.  Rename the hard-float functions
to ftype_hs_compare.  Convert float128 to FloatParts128.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 13:59:34 -07:00
Richard Henderson
e1c4667a9b softfloat: Move minmax_flags to softfloat-parts.c.inc
Rename to parts$N_minmax.  Combine 3 bool arguments to a bitmask.
Introduce ftype_minmax functions as a common optimization point.
Fold bfloat16 expansions into the same macro as the other types.

Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 13:59:34 -07:00
Richard Henderson
37c954a1b9 softfloat: Move uint_to_float to softfloat-parts.c.inc
Rename to parts$N_uint_to_float.
Reimplement uint64_to_float128 with FloatParts128.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 13:59:34 -07:00
Richard Henderson
e368951998 softfloat: Move int_to_float to softfloat-parts.c.inc
Rename to parts$N_sint_to_float.
Reimplement int{32,64}_to_float128 with FloatParts128.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 13:59:34 -07:00
Richard Henderson
4ab4aef018 softfloat: Move round_to_uint_and_pack to softfloat-parts.c.inc
Rename to parts$N_float_to_uint.  Reimplement
float128_to_uint{32,64}{_round_to_zero} with FloatParts128.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-03 13:59:34 -07:00
Richard Henderson
60c8f7265d softfpu: Add float_round_to_odd_inf
For Arm BFDOT and BFMMLA, we need a version of round-to-odd
that overflows to infinity, instead of the max normal number.

Cc: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210525225817.400336-6-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-06-03 16:43:26 +01:00
Richard Henderson
463b3f0d7f softfloat: Move round_to_int_and_pack to softfloat-parts.c.inc
Rename to parts$N_float_to_sint.  Reimplement
float128_to_int{32,64}{_round_to_zero} with FloatParts128.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16 07:13:51 -05:00
Richard Henderson
afc34931eb softfloat: Move round_to_int to softfloat-parts.c.inc
At the same time, convert to pointers, split out
parts$N_round_to_int_normal, define a macro for
parts_round_to_int using QEMU_GENERIC.

This necessarily meant some rearrangement to the
rount_to_{,u}int_and_pack routines, so go ahead and
convert to parts_round_to_int_normal, which in turn
allows cleaning up of the raised exception handling.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16 07:13:51 -05:00
Richard Henderson
ec961b81b4 softfloat: Move div_floats to softfloat-parts.c.inc
Rename to parts$N_div.
Implement float128_div with FloatParts128.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16 07:13:51 -05:00
Richard Henderson
dedd123c56 softfloat: Move muladd_floats to softfloat-parts.c.inc
Rename to parts$N_muladd.
Implement float128_muladd with FloatParts128.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16 07:13:51 -05:00
Richard Henderson
aca845275a softfloat: Move mul_floats to softfloat-parts.c.inc
Rename to parts$N_mul.
Reimplement float128_mul with FloatParts128.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16 07:13:51 -05:00
Richard Henderson
da10a9074a softfloat: Move addsub_floats to softfloat-parts.c.inc
In preparation for implementing multiple sizes.  Rename to parts_addsub,
split out parts_add/sub_normal for future reuse with muladd.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16 07:13:51 -05:00
Richard Henderson
ee6959f277 softfloat: Move round_canonical to softfloat-parts.c.inc
At the same time, convert to pointers, renaming to parts$N_uncanon,
and define a macro for parts_uncanon using QEMU_GENERIC.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16 07:13:51 -05:00
Richard Henderson
d46975bce1 softfloat: Move sf_canonicalize to softfloat-parts.c.inc
At the same time, convert to pointers, rename to parts$N_canonicalize
and define a macro for parts_canonicalize using QEMU_GENERIC.

Rearrange the cases to recognize float_class_normal as
early as possible.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16 07:13:51 -05:00
Richard Henderson
979582d071 softfloat: Move pick_nan_muladd to softfloat-parts.c.inc
At the same time, convert to pointers, rename to pick_nan_muladd$N
and define a macro for pick_nan_muladd using QEMU_GENERIC.

Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16 07:13:51 -05:00
Richard Henderson
22c355f417 softfloat: Move pick_nan to softfloat-parts.c.inc
At the same time, convert to pointers, rename to parts$N_pick_nan
and define a macro for parts_pick_nan using QEMU_GENERIC.

Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16 07:13:51 -05:00
Richard Henderson
7c45bad866 softfloat: Move return_nan to softfloat-parts.c.inc
At the same time, convert to pointers, rename to return_nan$N
and define a macro for return_nan using QEMU_GENERIC.

Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-16 07:13:51 -05:00