Commit Graph

34 Commits

Author SHA1 Message Date
Aurelien Jarno
e2f422047b softfloat: fix floatx80 handling of NaN
The floatx80 format uses an explicit bit that should be taken into account
when converting to and from commonNaN format.

When converting to commonNaN, the explicit bit should be removed if it is
a 1, and a default NaN should be used if it is 0.

When converting from commonNan, the explicit bit should be added.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-04-25 11:18:32 +02:00
Guan Xuetao
d2fbca9422 unicore32: necessary modifications for other files to support unicore32
Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-04-12 18:49:05 +00:00
Andreas Färber
bb98fe42c5 softfloat: Drop [s]bits{8, 16, 32, 64} types in favor of [u]int{8, 16, 32, 64}_t
They are defined with the same semantics as the POSIX types,
so prefer those for consistency. Suggested by Peter Maydell.

Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-03-21 21:46:14 +01:00
Andreas Färber
8d725fac63 softfloat: Prepend QEMU-style header with derivation notice
The SoftFloat license requires "prominent notice that the work
is derivative". Having added features like improved 16-bit support
for arm already, add such a notice to the sources.

softfloat-native.[ch] are not under the SoftFloat license
and thus are not changed.

Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-03-21 21:46:05 +01:00
Christophe Lyon
8559666ddb softfloat: move all default NaN definitions to softfloat.h.
These special values are needed to implement some helper functions,
which return/use these values in some cases.

Signed-off-by: Christophe Lyon <christophe.lyon@st.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-02-24 08:53:36 +01:00
Peter Maydell
f591e1bedf softfloat: Correctly handle NaNs in float16_to_float32()
Correctly handle NaNs in float16_to_float32(), by defining and
using a float16ToCommonNaN() function, as we do with the other formats.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-02-10 18:28:29 +01:00
Peter Maydell
600e30d2b2 softfloat: Fix single-to-half precision float conversions
Fix various bugs in the single-to-half-precision conversion code:
 * input NaNs not correctly converted in IEEE mode
   (fixed by defining and using a commonNaNToFloat16())
 * wrong values returned when converting NaN/Inf into non-IEEE
   half precision value
 * wrong values returned for conversion of values which are
   on the boundary between denormal and zero for the half
   precision format
 * zeroes not correctly identified
 * excessively large results in non-IEEE mode should
   generate InvalidOp, not Overflow

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-02-10 18:28:21 +01:00
Christophe Lyon
bcd4d9afd4 softfloat: Honour default_nan_mode for float-to-float conversions
Honour the default_nan_mode flag when doing conversions between
different floating point formats, as well as when returning a NaN from
a two-operand floating point function. This corrects the behaviour
of float<->double conversions on both ARM and SH4.

Signed-off-by: Christophe Lyon <christophe.lyon@st.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-02-10 18:28:19 +01:00
Peter Maydell
bb4d4bb376 softfloat: Add float16 type and float16 NaN handling functions
Add a float16 type to softfloat, rather than using bits16 directly.
Also add the missing functions float16_is_quiet_nan(),
float16_is_signaling_nan() and float16_maybe_silence_nan(),
which are needed for the float16 conversion routines.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-02-10 18:28:09 +01:00
Aurelien Jarno
de4af5f792 softfloat: fix floatx80_is_{quiet,signaling}_nan()
floatx80_is_{quiet,signaling}_nan() functions are incorrectly detecting
the type of NaN, depending on SNAN_BIT_IS_ONE, one of the two is
returning the correct value, and the other true for any kind of NaN.

This patch fixes that by applying the same kind of comparison as for
other float formats, but taking into account the explicit bit.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-20 12:37:20 +01:00
Aurelien Jarno
102016020b softfloat: fix default-NaN mode
When the default-NaN mode is enabled, it should return the default NaN
value, but it should anyway raise the invalid operation flag if one of
the operand is an sNaN.

I have checked that this behavior matches the ARM and SH4 manuals, as
well as real SH4 hardware.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-14 20:39:17 +01:00
Aurelien Jarno
e90877507e softfloat: SH4 has the sNaN bit set
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-14 20:39:17 +01:00
Aurelien Jarno
e024e881bb target-ppc: Implement correct NaN propagation rules
Implement the correct NaN propagation rules for PowerPC targets by
providing an appropriate pickNaN function.

Also fix the #ifdef tests for default NaN definition, the correct name
is TARGET_PPC instead of TARGET_POWERPC.

Reviewed-by: Nathan Froyd <froydnj@codesourcery.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-06 16:29:42 +01:00
Aurelien Jarno
084d19ba71 target-mips: Implement correct NaN propagation rules
Implement the correct NaN propagation rules for MIPS targets by
providing an appropriate pickNaN function.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-06 16:29:35 +01:00
Aurelien Jarno
1f398e0825 softfloat: use float{32,64,x80,128}_maybe_silence_nan()
Use float{32,64,x80,128}_maybe_silence_nan() instead of toggling the
sNaN bit manually. This allow per target implementation of sNaN to qNaN
conversion.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2011-01-06 16:29:29 +01:00
Aurelien Jarno
f6a7d92aed softfloat: add float{x80,128}_maybe_silence_nan()
Add float{x80,128}_maybe_silence_nan() functions, they will be need by
propagateFloat{x80,128}NaN().

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-06 16:29:23 +01:00
Aurelien Jarno
93ae1c6fea softfloat: fix float{32,64}_maybe_silence_nan() for MIPS
On targets that define sNaN with the sNaN bit as one, simply clearing
this bit may correspond to an infinite value.

Convert it to a default NaN if SNAN_BIT_IS_ONE, as it corresponds to
the MIPS implementation, the only emulated CPU with SNAN_BIT_IS_ONE.
When other CPU of this type are added, this might be updated to include
more cases.

Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-06 16:29:17 +01:00
Aurelien Jarno
d735d695e7 softfloat: rename *IsNaN variables to *IsQuietNaN
Similarly to what has been done in commit
185698715d rename the misnamed *IsNaN
variables into *IsQuietNaN.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-06 16:29:11 +01:00
Aurelien Jarno
34d2386198 softfloat: remove HPPA specific code
We don't have any HPPA target, so let's remove HPPA specific code. It
can be re-added when someone adds an HPPA target.

This has been blessed by Stuart Brady <sdb@zubnet.me.uk>, author of the
target-hppa fork.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-06 16:29:05 +01:00
Peter Maydell
011da610ba target-arm: Implement correct NaN propagation rules
Implement the correct NaN propagation rules for ARM targets by
providing an appropriate pickNaN function.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-02 23:59:03 +01:00
Peter Maydell
354f211b1a softfloat: abstract out target-specific NaN propagation rules
IEEE754 doesn't specify precisely what NaN should be returned as
the result of an operation on two input NaNs. This is therefore
target-specific. Abstract out the code in propagateFloat*NaN()
which was implementing the x87 propagation rules, so that it
can be easily replaced on a per-target basis.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-02 23:58:57 +01:00
Peter Maydell
185698715d softfloat: Rename float*_is_nan() functions to float*_is_quiet_nan()
The softfloat functions float*_is_nan() were badly misnamed,
because they return true only for quiet NaNs, not for all NaNs.
Rename them to float*_is_quiet_nan() to more accurately reflect
what they do.

This change was produced by:
 perl -p -i -e 's/_is_nan/_is_quiet_nan/g' $(git grep -l is_nan)
(with the results manually checked.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Nathan Froyd <froydnj@codesourcery.com>
Acked-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-02 11:15:25 +01:00
Peter Maydell
b408dbdec3 softfloat: Add float*_maybe_silence_nan() functions
Add functions float*_maybe_silence_nan() which ensure that a
value is not a signaling NaN by turning it into a quiet NaN.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Nathan Froyd <froydnj@codesourcery.com>
2010-12-07 15:37:34 +00:00
Richard Henderson
990b3e1901 target-alpha: Enable softfloat.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2009-12-13 20:32:36 +01:00
blueswir1
70c14705c3 Sparse fixes: dubious mixing of bitwise and logical operations
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6741 c046a42c-6fe2-441c-8c8c-71466251a162
2009-03-07 16:03:05 +00:00
pbrook
5c7908ed23 Implement default-NaN mode.
Signed-off-by: Paul Brook <paul@codesourcery.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6106 c046a42c-6fe2-441c-8c8c-71466251a162
2008-12-19 13:53:37 +00:00
pbrook
9027db892a Fix ARM default NaN.
Signed-off-by: Paul Brook <paul@codesourcery.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5618 c046a42c-6fe2-441c-8c8c-71466251a162
2008-11-04 12:33:21 +00:00
blueswir1
b1d8e52e63 Fix undeclared symbol warnings from sparse
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5539 c046a42c-6fe2-441c-8c8c-71466251a162
2008-10-26 13:43:07 +00:00
ths
85016c983c Assortment of soft-float fixes, by Aurelien Jarno.
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3860 c046a42c-6fe2-441c-8c8c-71466251a162
2007-12-25 23:59:51 +00:00
pbrook
f090c9d4ad Add strict checking mode for softfp code.
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3688 c046a42c-6fe2-441c-8c8c-71466251a162
2007-11-18 14:33:24 +00:00
ths
5a6932d51d Fix NaN handling for MIPS and HPPA.
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3655 c046a42c-6fe2-441c-8c8c-71466251a162
2007-11-16 14:57:36 +00:00
ths
b645bb4885 Fix softfloat NaN handling.
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@2805 c046a42c-6fe2-441c-8c8c-71466251a162
2007-05-11 17:10:14 +00:00
bellard
750afe93fd avoid using char when it is not necessary
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@2204 c046a42c-6fe2-441c-8c8c-71466251a162
2006-10-28 19:27:11 +00:00
bellard
158142c2c2 soft float support
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1332 c046a42c-6fe2-441c-8c8c-71466251a162
2005-03-13 16:54:06 +00:00