Hi Jeff,
[...]
+ "#"
+ "&& 1"
+ [(const_int 0)]
+ "{
+ /* If we do not have an RMW operand, then copy the input
+ to the output before this insn. Also modify the existing
+ insn in-place so we can have make_field_assignment actually
+ generate a suitable extraction. */
+ if (!rtx_equal_p (operands[0], operands[1]))
+ {
+ emit_move_insn (operands[0], operands[1]);
+ XEXP (XEXP (SET_SRC (PATTERN (curr_insn)), 0), 0) = copy_rtx (operands[0]);
+ }
+
+ rtx make_field_assignment (rtx);
+ rtx newpat = make_field_assignment (PATTERN (curr_insn));
+ gcc_assert (newpat);
+ emit_insn (newpat);
+ DONE;
It seems that make_field_assignment returns a new pattern only if it
succeeds and returns the same pattern otherwise. So I am wondering if
it is worth simplifying the above. Like removing the assert and
checking/inserting move only when new pattern is returned?
Thanks,
Kugan
>
> Jeff
