1 files changed, 11 insertions, 0 deletions
diff --git a/compiler-rt/lib/memprof/memprof_mibmap.cpp b/compiler-rt/lib/memprof/memprof_mibmap.cpp
index 32f0796c8f24..a49ed8bf4fd6 100644
--- a/compiler-rt/lib/memprof/memprof_mibmap.cpp
+++ b/compiler-rt/lib/memprof/memprof_mibmap.cpp
@@ -30,7 +30,18 @@ void InsertOrMerge(const uptr Id, const MemInfoBlock &Block, MIBMapTy &Map) {
   } else {
     LockedMemInfoBlock *lmib = *h;
     SpinMutexLock lock(&lmib->mutex);
+    uintptr_t ShorterHistogram;
+    if (Block.AccessHistogramSize > lmib->mib.AccessHistogramSize)
+      ShorterHistogram = lmib->mib.AccessHistogram;
+    else
+      ShorterHistogram = Block.AccessHistogram;
+
     lmib->mib.Merge(Block);
+    // The larger histogram is kept and the shorter histogram is discarded after
+    // adding the counters to the larger historam. Free only the shorter
+    // Histogram
+    if (Block.AccessHistogramSize > 0 || lmib->mib.AccessHistogramSize > 0)
+      InternalFree((void *)ShorterHistogram);
   }
 }