Currently we hardcode the default NaN value in parts64_default_nan()
using a compile-time ifdef ladder. This is awkward for two cases:
* for single-QEMU-binary we can't hard-code target-specifics like this
* for Arm FEAT_AFP the default NaN value depends on FPCR.AH
(specifically the sign bit is different)
Add a field to float_status to specify the default NaN value; fall
back to the old ifdef behaviour if these are not set.
The default NaN value is specified by setting a uint8_t to a
pattern corresponding to the sign and upper fraction parts of
the NaN; the lower bits of the fraction are set from bit 0 of
the pattern.
Signed-off-by: Peter Maydell<peter.maydell@linaro.org>
---
include/fpu/softfloat-helpers.h | 11 +++++++
include/fpu/softfloat-types.h | 10 ++++++
fpu/softfloat-specialize.c.inc | 55 ++++++++++++++++++++-------------
3 files changed, 54 insertions(+), 22 deletions(-)