tree 38427efffa6caae63622feaa978eb62554283324
parent 941ef3db03fe40cec04fbf0102d1aa14711c708d
author Richard Henderson <rth@twiddle.net> 1497810398 -0700
committer Richard Henderson <rth@twiddle.net> 1500325997 -0700

target/s390x: Tidy SRST

Since we require all registers saved on input, read R0 from ENV instead
of passing it manually.  Recognize the specification exception when R0
contains incorrect data.  Keep high bits of result registers unmodified
when in 31 or 24-bit mode.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>