This fixes a problem because cc_plus and cc_minus are in the wrong places in
calls of avr_out_plus_1. This is important when avr_out_plus is called from
notice_update_cc. This means that cc_status might be determined incorrectly.
In the vast majority of cases this leads to performance regression because of
superfluous comparisons when an addition (using SUB instructions) has already
set the condition code.
But there are also cases where this might lead to wrong code.
No changes in test suite results.
Ok to apply?
I didn't follow this list for some time. Is trunk open for such changes?
If so, I would apply it to trunk and 4.8 branch, otherwise to 4.8, 4.9 and
trunk once they are open again.
Johann
PR target/60486
* config/avr/avr.c (avr_out_plus): Swap cc_plus and cc_minus in
calls of avr_out_plus_1.
Index: config/avr/avr.c
===================================================================
--- config/avr/avr.c (revision 208473)
+++ config/avr/avr.c (working copy)
@@ -6812,8 +6812,8 @@ avr_out_plus (rtx insn, rtx *xop, int *p
/* Work out the shortest sequence. */
- avr_out_plus_1 (op, &len_minus, MINUS, &cc_plus, code_sat, sign, out_label);
- avr_out_plus_1 (op, &len_plus, PLUS, &cc_minus, code_sat, sign, out_label);
+ avr_out_plus_1 (op, &len_minus, MINUS, &cc_minus, code_sat, sign, out_label);
+ avr_out_plus_1 (op, &len_plus, PLUS, &cc_plus, code_sat, sign, out_label);
if (plen)
{
