When I wrote 71e9766519, there was an interaction I didn't take into
account: When setting eq, SetCRFieldBit assumes that all bits in the
passed-in host register except the least significant bit are 0. But if
we use EON or ORN, all bits except the least significant bit get set to
1. This can cause eq to end up unset when it should be set.
This commit fixes the issue.
crandc is unaffected by the issue because the "1" bits get ANDed with
"0" bits from the first operand.
Note that in practice, we never have both bits_1_to_31_are_set and
negate at once, so while it looks like this commit adds an extra AND
instruction in some cases, those cases don't happen in practice, meaning
this fix shouldn't affect performance.
aa9696e1c1