Fix bump-pointer-space walk for black-dense

Also add post-gc heap-verification.

Bug: 343220989
Test: art/test/testrunner/testrunner.py --host --debug
Change-Id: I69878f81ad49994a6437f04e66eb8e607964340f

2 files changed, 3 insertions, 1 deletions

diff --git a/runtime/gc/collector/mark_compact.cc b/runtime/gc/collector/mark_compact.cc
index 1713e67120..a7af756970 100644
--- a/runtime/gc/collector/mark_compact.cc
+++ b/runtime/gc/collector/mark_compact.cc
@@ -787,6 +787,7 @@ void MarkCompact::RunPhases() {
     }
   }
   FinishPhase();
+  GetHeap()->PostGcVerification(this);
   thread_running_gc_ = nullptr;
 }
 
@@ -1061,6 +1062,7 @@ bool MarkCompact::PrepareForCompaction() {
   // We shouldn't be consuming more space after compaction than pre-compaction.
   CHECK_GE(black_objs_slide_diff_, 0);
   if (black_objs_slide_diff_ == 0) {
+    black_dense_end_ = black_allocations_begin_;
     return false;
   }
   for (size_t i = vector_len; i < vector_length_; i++) {
diff --git a/runtime/gc/space/bump_pointer_space-walk-inl.h b/runtime/gc/space/bump_pointer_space-walk-inl.h
index 38e02d5829..26402e8d3d 100644
--- a/runtime/gc/space/bump_pointer_space-walk-inl.h
+++ b/runtime/gc/space/bump_pointer_space-walk-inl.h
@@ -115,7 +115,7 @@ inline void BumpPointerSpace::Walk(Visitor&& visitor) {
       if (ptr > pos) {
         // Adjust block-size in case 'pos' is in the middle of the block.
         if (static_cast<ssize_t>(block_size) > ptr - pos) {
-          (*block_sizes_copy)[iter] -= ptr - pos;
+          (*block_sizes_copy)[iter] = ptr - pos;
         }
         break;
       }