Grep in Fedora 39 has started warning when invoked as 'egrep',
so use grep -E instead to avoid the warnings.

Signed-off-by: Paul Mackerras <[email protected]>

The sign recorded in FPRF was sometimes wrong because we weren't doing
the modifications that were done in pack_dp when setting FPRF (FPSCR
field).  These modifications are: set sign for zero result of
subtraction based on rounding mode; negate result for fnmadd/sub;
but don't modify sign of NaNs.

Instead we now do these modifications in the main state machine code
and put the result in an 'rsign' variable that is used to set
v.res_sign, then r.res_sign is used in the next cycle both for setting
FPRF and in the pack_dp functions.  That simplifies pack_dp and lets
us get rid of r.res_negate, r.res_subtract and r.res_rmode.

Signed-off-by: Paul Mackerras <[email protected]>

Signed-off-by: Paul Mackerras <[email protected]>

Renormalization of the divisor for fdiv[s] was adjusting the result
exponent in the wrong direction, making the result smaller in
magnitude than it should be by a power of 2.  Fix this by negating
r.shift in the RENORM_B2 state and then subtracting it in the LOOKUP
cycle.

Signed-off-by: Paul Mackerras <[email protected]>

Signed-off-by: Paul Mackerras <[email protected]>