(subst): Move simple operations inside IF_THEN_ELSE if the IF_THEN_ELSE is in…

(subst): Move simple operations inside IF_THEN_ELSE if the IF_THEN_ELSE is in the second operand as well as the first.

(subst): Move simple operations inside IF_THEN_ELSE if the IF_THEN_ELSE is in
the second operand as well as the first.
(subst, case NEG): Use plus_constant to make a PLUS.
(subst, case MINUS): Simplify (minus 1 (comparison foo bar)).
(subst, case EQ): Add a number of missing cases where comparisons may be
replaced with arithmetic or logical ops.
(subst, case IF_THEN_ELSE): Handle (if_then_else COND (OP Z C1) Z) in a more
general manner.
(simplify_and_const_int): Make AND with gen_binary in case we can simplify it.

From-SVN: r5056