diff --git a/pico/32x/memory.c b/pico/32x/memory.c
index 3f597288..69f70318 100644
--- a/pico/32x/memory.c
+++ b/pico/32x/memory.c
@@ -114,12 +114,13 @@ void p32x_m68k_poll_event(u32 flags)
 void NOINLINE p32x_sh2_poll_detect(u32 a, SH2 *sh2, u32 flags, int maxcnt)
 {
   u32 cycles_done = sh2_cycles_done_t(sh2);
+  u32 cycles_diff = cycles_done - sh2->poll_cycles;
 
   // reading 2 consecutive 16bit values is probably a 32bit access. detect this
   // by checking address (max 2 bytes away) and cycles (max 2 cycles later).
   // no polling if more than 20 cycles have passed since last detect call.
-  if (a - sh2->poll_addr <= 2 && CYCLES_GE(sh2->poll_cycles+20, cycles_done)) {
-    if (CYCLES_GT(cycles_done,sh2->poll_cycles+2) && ++sh2->poll_cnt >= maxcnt) {
+  if (a - sh2->poll_addr <= 2 && CYCLES_GE(20, cycles_diff)) {
+    if (CYCLES_GT(cycles_diff, 2) && ++sh2->poll_cnt >= maxcnt) {
       if (!(sh2->state & flags))
         elprintf_sh2(sh2, EL_32X, "state: %02x->%02x",
           sh2->state, sh2->state | flags);