kernel/vm/vm_address_region.cpp

441     vaddr_t gap_end; // last byte of a gap
463         if (sub_overflow(next->base(), 1, &gap_end) ||
464             sub_overflow(gap_end, min_gap, &gap_end)) {
471         if (add_overflow(base_, size_ - 1, &gap_end)) {
476     DEBUG_ASSERT(gap_end > gap_beg);
479     if (gap_end <= search_base) {
486     DEBUG_ASSERT(gap_end > gap_beg);
489                   search_base, gap_beg, gap_end);
499     *pva = aspace_->arch_aspace().PickSpot(gap_beg, prev_arch_mmu_flags, gap_end,
505     if (*pva < gap_end && ((gap_end - *pva + 1) >= region_size)) {