diff options
Diffstat (limited to 'klippy')
| -rw-r--r-- | klippy/stepcompress.c | 18 |
1 files changed, 7 insertions, 11 deletions
diff --git a/klippy/stepcompress.c b/klippy/stepcompress.c index 72ff101f..6bcdb284 100644 --- a/klippy/stepcompress.c +++ b/klippy/stepcompress.c @@ -95,13 +95,6 @@ idiv_down(int32_t n, int32_t d) return (n>=0) ? (n/d) : (n - d + 1) / d; } -// Calculate the impact of each 'add' for a sequence with 'count' steps -static inline int32_t -calc_addfactor(int32_t count) -{ - return (uint32_t)count*(count-1)/2; -} - struct points { int32_t minp, maxp; }; @@ -157,7 +150,7 @@ compress_bisect_add(struct stepcompress *sc) return (struct step_move){ interval, count, add }; } nextpoint = minmax_point(sc, sc->queue_pos + nextcount - 1); - int32_t nextaddfactor = calc_addfactor(nextcount); + int32_t nextaddfactor = nextcount*(nextcount-1)/2; int32_t c = add*nextaddfactor; if (nextmininterval*nextcount < nextpoint.minp - c) nextmininterval = DIV_UP(nextpoint.minp - c, nextcount); @@ -169,7 +162,7 @@ compress_bisect_add(struct stepcompress *sc) } // Check if this is the best sequence found so far - int32_t count = nextcount - 1, addfactor = calc_addfactor(count); + int32_t count = nextcount - 1, addfactor = count*(count-1)/2; int32_t reach = add*addfactor + interval*count; if (reach > bestreach || (reach == bestreach && interval > bestinterval)) { @@ -181,10 +174,13 @@ compress_bisect_add(struct stepcompress *sc) zerointerval = interval; zerocount = count; } + if (count > 0x200) + // No 'add' will improve sequence; avoid integer overflow + break; } // Check if a greater or lesser add could extend the sequence - int32_t nextaddfactor = calc_addfactor(nextcount); + int32_t nextaddfactor = nextcount*(nextcount-1)/2; int32_t nextreach = add*nextaddfactor + interval*nextcount; if (nextreach < nextpoint.minp) { minadd = add + 1; @@ -339,7 +335,7 @@ stepcompress_flush(struct stepcompress *sc, uint64_t move_clock) // Be careful with 32bit overflow sc->last_step_clock = qm->req_clock = *sc->queue_pos; } else { - int32_t addfactor = calc_addfactor(move.count); + int32_t addfactor = move.count*(move.count-1)/2; uint32_t ticks = move.add*addfactor + move.interval*move.count; sc->last_step_clock += ticks; } |