@@ -3228,6 +3228,41 @@ noce_convert_multiple_sets (struct noce_if_info *if_info)
if (if_info->then_else_reversed)
std::swap (old_val, new_val);
+
+ /* We allow simple lowpart register subreg SET sources in
+ bb_ok_for_noce_convert_multiple_sets. Be careful when processing
+ sequences like:
+ (set (reg:SI r1) (reg:SI r2))
+ (set (reg:HI r3) (subreg:HI (r1)))
+ For the second insn new_val or old_val (r1 in this example) will be
+ taken from the temporaries and have the wider mode which will not
+ match with the mode of the other source of the conditional move, so
+ we'll end up trying to emit r4:HI = cond ? (r1:SI) : (r3:HI).
+ Wrap the two cmove operands into subregs if appropriate to prevent
+ that. */
+ if (GET_MODE (new_val) != GET_MODE (temp))
+ {
+ machine_mode src_mode = GET_MODE (new_val);
+ machine_mode dst_mode = GET_MODE (temp);
+ if (GET_MODE_SIZE (src_mode) <= GET_MODE_SIZE (dst_mode))
+ {
+ end_sequence ();
+ return FALSE;
+ }
+ new_val = lowpart_subreg (dst_mode, new_val, src_mode);
+ }
+ if (GET_MODE (old_val) != GET_MODE (temp))
+ {
+ machine_mode src_mode = GET_MODE (old_val);
+ machine_mode dst_mode = GET_MODE (temp);
+ if (GET_MODE_SIZE (src_mode) <= GET_MODE_SIZE (dst_mode))
+ {
+ end_sequence ();
+ return FALSE;
+ }
+ old_val = lowpart_subreg (dst_mode, old_val, src_mode);
+ }
+
/* Actually emit the conditional move. */
rtx temp_dest = noce_emit_cmove (if_info, temp, cond_code,
x, y, new_val, old_val);
new file mode 100644
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "--param max-rtl-if-conversion-insns=2" } */
+
+unsigned short a;
+int b, c;
+int *d;
+void fn1() {
+ *d = 24;
+ for (; *d <= 65;) {
+ unsigned short *e = &a;
+ b = (a &= 0 <= 0) < (c ?: (*e %= *d));
+ for (; *d <= 83;)
+ ;
+ }
+}