Skip frozen segments for commit accounting (#75738)

src/coreclr/gc/gc.cpp

@@ -30487,8 +30487,11 @@ void gc_heap::plan_phase (int condemned_gen_number)
 #endif // MULTIPLE_HEAPS
                             heap_segment* region = generation_start_segment (hp->generation_of (i));
                             while (region)
+                            {
+                                if (!heap_segment_read_only_p (region))
                                 {
                                     committed += heap_segment_committed (region) - get_region_start (region);
+                                }
                                 region = heap_segment_next (region);
                             }
 
@@ -43916,9 +43919,12 @@ void gc_heap::verify_regions (int gen_number, bool can_verify_gen_num, bool can_
     while (seg_in_gen)
     {
         if (p_total_committed)
+        {
+            if (!heap_segment_read_only_p (seg_in_gen))
             {
                 *p_total_committed += (heap_segment_committed (seg_in_gen) - get_region_start (seg_in_gen));
             }
+        }
         if (can_verify_gen_num)
         {
             if (heap_segment_gen_num (seg_in_gen) != min (gen_number, max_generation))