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>
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>
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>
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>
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>
Implement the correct NaN propagation rules for MIPS targets by
providing an appropriate pickNaN function.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
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>
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>
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>
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>
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>
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>
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>
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>
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>
