diff --git a/compiler-rt/lib/memprof/CMakeLists.txt b/compiler-rt/lib/memprof/CMakeLists.txt
--- a/compiler-rt/lib/memprof/CMakeLists.txt
+++ b/compiler-rt/lib/memprof/CMakeLists.txt
@@ -35,6 +35,7 @@
   memprof_interface_internal.h
   memprof_internal.h
   memprof_mapping.h
+  memprof_meminfoblock.h
   memprof_stack.h
   memprof_stats.h
   memprof_thread.h
diff --git a/compiler-rt/lib/memprof/memprof_allocator.cpp b/compiler-rt/lib/memprof/memprof_allocator.cpp
--- a/compiler-rt/lib/memprof/memprof_allocator.cpp
+++ b/compiler-rt/lib/memprof/memprof_allocator.cpp
@@ -15,6 +15,7 @@
 
 #include "memprof_allocator.h"
 #include "memprof_mapping.h"
+#include "memprof_meminfoblock.h"
 #include "memprof_stack.h"
 #include "memprof_thread.h"
 #include "sanitizer_common/sanitizer_allocator_checks.h"
@@ -166,113 +167,12 @@
   return &ms->allocator_cache;
 }
 
-struct MemInfoBlock {
-  u32 alloc_count;
-  u64 total_access_count, min_access_count, max_access_count;
-  u64 total_size;
-  u32 min_size, max_size;
-  u32 alloc_timestamp, dealloc_timestamp;
-  u64 total_lifetime;
-  u32 min_lifetime, max_lifetime;
-  u32 alloc_cpu_id, dealloc_cpu_id;
-  u32 num_migrated_cpu;
-
-  // Only compared to prior deallocated object currently.
-  u32 num_lifetime_overlaps;
-  u32 num_same_alloc_cpu;
-  u32 num_same_dealloc_cpu;
-
-  u64 data_type_id; // TODO: hash of type name
-
-  MemInfoBlock() : alloc_count(0) {}
-
-  MemInfoBlock(u32 size, u64 access_count, u32 alloc_timestamp,
-               u32 dealloc_timestamp, u32 alloc_cpu, u32 dealloc_cpu)
-      : alloc_count(1), total_access_count(access_count),
-        min_access_count(access_count), max_access_count(access_count),
-        total_size(size), min_size(size), max_size(size),
-        alloc_timestamp(alloc_timestamp), dealloc_timestamp(dealloc_timestamp),
-        total_lifetime(dealloc_timestamp - alloc_timestamp),
-        min_lifetime(total_lifetime), max_lifetime(total_lifetime),
-        alloc_cpu_id(alloc_cpu), dealloc_cpu_id(dealloc_cpu),
-        num_lifetime_overlaps(0), num_same_alloc_cpu(0),
-        num_same_dealloc_cpu(0) {
-    num_migrated_cpu = alloc_cpu_id != dealloc_cpu_id;
-  }
-
-  void Print(u64 id) {
-    u64 p;
-    if (flags()->print_terse) {
-      p = total_size * 100 / alloc_count;
-      Printf("MIB:%llu/%u/%llu.%02llu/%u/%u/", id, alloc_count, p / 100, p % 100,
-             min_size, max_size);
-      p = total_access_count * 100 / alloc_count;
-      Printf("%llu.%02llu/%llu/%llu/", p / 100, p % 100, min_access_count,
-             max_access_count);
-      p = total_lifetime * 100 / alloc_count;
-      Printf("%llu.%02llu/%u/%u/", p / 100, p % 100, min_lifetime, max_lifetime);
-      Printf("%u/%u/%u/%u\n", num_migrated_cpu, num_lifetime_overlaps,
-             num_same_alloc_cpu, num_same_dealloc_cpu);
-    } else {
-      p = total_size * 100 / alloc_count;
-      Printf("Memory allocation stack id = %llu\n", id);
-      Printf("\talloc_count %u, size (ave/min/max) %llu.%02llu / %u / %u\n",
-             alloc_count, p / 100, p % 100, min_size, max_size);
-      p = total_access_count * 100 / alloc_count;
-      Printf("\taccess_count (ave/min/max): %llu.%02llu / %llu / %llu\n", p / 100,
-             p % 100, min_access_count, max_access_count);
-      p = total_lifetime * 100 / alloc_count;
-      Printf("\tlifetime (ave/min/max): %llu.%02llu / %u / %u\n", p / 100, p % 100,
-             min_lifetime, max_lifetime);
-      Printf("\tnum migrated: %u, num lifetime overlaps: %u, num same alloc "
-             "cpu: %u, num same dealloc_cpu: %u\n",
-             num_migrated_cpu, num_lifetime_overlaps, num_same_alloc_cpu,
-             num_same_dealloc_cpu);
-    }
-  }
-
-  static void printHeader() {
-    CHECK(flags()->print_terse);
-    Printf("MIB:StackID/AllocCount/AveSize/MinSize/MaxSize/AveAccessCount/"
-           "MinAccessCount/MaxAccessCount/AveLifetime/MinLifetime/MaxLifetime/"
-           "NumMigratedCpu/NumLifetimeOverlaps/NumSameAllocCpu/"
-           "NumSameDeallocCpu\n");
-  }
-
-  void Merge(MemInfoBlock &newMIB) {
-    alloc_count += newMIB.alloc_count;
-
-    total_access_count += newMIB.total_access_count;
-    min_access_count = Min(min_access_count, newMIB.min_access_count);
-    max_access_count = Max(max_access_count, newMIB.max_access_count);
-
-    total_size += newMIB.total_size;
-    min_size = Min(min_size, newMIB.min_size);
-    max_size = Max(max_size, newMIB.max_size);
-
-    total_lifetime += newMIB.total_lifetime;
-    min_lifetime = Min(min_lifetime, newMIB.min_lifetime);
-    max_lifetime = Max(max_lifetime, newMIB.max_lifetime);
-
-    // We know newMIB was deallocated later, so just need to check if it was
-    // allocated before last one deallocated.
-    num_lifetime_overlaps += newMIB.alloc_timestamp < dealloc_timestamp;
-    alloc_timestamp = newMIB.alloc_timestamp;
-    dealloc_timestamp = newMIB.dealloc_timestamp;
-
-    num_same_alloc_cpu += alloc_cpu_id == newMIB.alloc_cpu_id;
-    num_same_dealloc_cpu += dealloc_cpu_id == newMIB.dealloc_cpu_id;
-    alloc_cpu_id = newMIB.alloc_cpu_id;
-    dealloc_cpu_id = newMIB.dealloc_cpu_id;
-  }
-};
-
 struct SetEntry {
   SetEntry() : id(0), MIB() {}
   bool Empty() { return id == 0; }
   void Print() {
     CHECK(!Empty());
-    MIB.Print(id);
+    MIB.Print(id, flags()->print_terse);
   }
   // The stack id
   u64 id;
diff --git a/compiler-rt/lib/memprof/memprof_meminfoblock.h b/compiler-rt/lib/memprof/memprof_meminfoblock.h
new file mode 100644
--- /dev/null
+++ b/compiler-rt/lib/memprof/memprof_meminfoblock.h
@@ -0,0 +1,116 @@
+#ifndef MEMPROF_MEMINFOBLOCK_H_
+#define MEMPROF_MEMINFOBLOCK_H_
+
+#include "memprof_interface_internal.h" // For u32, u64 TODO: Move these out of the internal header.
+#include "sanitizer_common/sanitizer_common.h"
+
+namespace __memprof {
+
+using __sanitizer::Printf;
+
+struct MemInfoBlock {
+  u32 alloc_count;
+  u64 total_access_count, min_access_count, max_access_count;
+  u64 total_size;
+  u32 min_size, max_size;
+  u32 alloc_timestamp, dealloc_timestamp;
+  u64 total_lifetime;
+  u32 min_lifetime, max_lifetime;
+  u32 alloc_cpu_id, dealloc_cpu_id;
+  u32 num_migrated_cpu;
+
+  // Only compared to prior deallocated object currently.
+  u32 num_lifetime_overlaps;
+  u32 num_same_alloc_cpu;
+  u32 num_same_dealloc_cpu;
+
+  u64 data_type_id; // TODO: hash of type name
+
+  MemInfoBlock() : alloc_count(0) {}
+
+  MemInfoBlock(u32 size, u64 access_count, u32 alloc_timestamp,
+               u32 dealloc_timestamp, u32 alloc_cpu, u32 dealloc_cpu)
+      : alloc_count(1), total_access_count(access_count),
+        min_access_count(access_count), max_access_count(access_count),
+        total_size(size), min_size(size), max_size(size),
+        alloc_timestamp(alloc_timestamp), dealloc_timestamp(dealloc_timestamp),
+        total_lifetime(dealloc_timestamp - alloc_timestamp),
+        min_lifetime(total_lifetime), max_lifetime(total_lifetime),
+        alloc_cpu_id(alloc_cpu), dealloc_cpu_id(dealloc_cpu),
+        num_lifetime_overlaps(0), num_same_alloc_cpu(0),
+        num_same_dealloc_cpu(0) {
+    num_migrated_cpu = alloc_cpu_id != dealloc_cpu_id;
+  }
+
+  void Print(u64 id, bool print_terse) const {
+    u64 p;
+
+    if (print_terse) {
+      p = total_size * 100 / alloc_count;
+      Printf("MIB:%llu/%u/%llu.%02llu/%u/%u/", id, alloc_count, p / 100,
+             p % 100, min_size, max_size);
+      p = total_access_count * 100 / alloc_count;
+      Printf("%llu.%02llu/%llu/%llu/", p / 100, p % 100, min_access_count,
+             max_access_count);
+      p = total_lifetime * 100 / alloc_count;
+      Printf("%llu.%02llu/%u/%u/", p / 100, p % 100, min_lifetime,
+             max_lifetime);
+      Printf("%u/%u/%u/%u\n", num_migrated_cpu, num_lifetime_overlaps,
+             num_same_alloc_cpu, num_same_dealloc_cpu);
+    } else {
+      p = total_size * 100 / alloc_count;
+      Printf("Memory allocation stack id = %llu\n", id);
+      Printf("\talloc_count %u, size (ave/min/max) %llu.%02llu / %u / %u\n",
+             alloc_count, p / 100, p % 100, min_size, max_size);
+      p = total_access_count * 100 / alloc_count;
+      Printf("\taccess_count (ave/min/max): %llu.%02llu / %llu / %llu\n",
+             p / 100, p % 100, min_access_count, max_access_count);
+      p = total_lifetime * 100 / alloc_count;
+      Printf("\tlifetime (ave/min/max): %llu.%02llu / %u / %u\n", p / 100,
+             p % 100, min_lifetime, max_lifetime);
+      Printf("\tnum migrated: %u, num lifetime overlaps: %u, num same alloc "
+             "cpu: %u, num same dealloc_cpu: %u\n",
+             num_migrated_cpu, num_lifetime_overlaps, num_same_alloc_cpu,
+             num_same_dealloc_cpu);
+    }
+  }
+
+  static void printHeader() {
+    Printf("MIB:StackID/AllocCount/AveSize/MinSize/MaxSize/AveAccessCount/"
+           "MinAccessCount/MaxAccessCount/AveLifetime/MinLifetime/MaxLifetime/"
+           "NumMigratedCpu/NumLifetimeOverlaps/NumSameAllocCpu/"
+           "NumSameDeallocCpu\n");
+  }
+
+  void Merge(const MemInfoBlock &newMIB) {
+    alloc_count += newMIB.alloc_count;
+
+    total_access_count += newMIB.total_access_count;
+    min_access_count = Min(min_access_count, newMIB.min_access_count);
+    max_access_count = Max(max_access_count, newMIB.max_access_count);
+
+    total_size += newMIB.total_size;
+    min_size = Min(min_size, newMIB.min_size);
+    max_size = Max(max_size, newMIB.max_size);
+
+    total_lifetime += newMIB.total_lifetime;
+    min_lifetime = Min(min_lifetime, newMIB.min_lifetime);
+    max_lifetime = Max(max_lifetime, newMIB.max_lifetime);
+
+    // We know newMIB was deallocated later, so just need to check if it was
+    // allocated before last one deallocated.
+    num_lifetime_overlaps += newMIB.alloc_timestamp < dealloc_timestamp;
+    alloc_timestamp = newMIB.alloc_timestamp;
+    dealloc_timestamp = newMIB.dealloc_timestamp;
+
+    num_same_alloc_cpu += alloc_cpu_id == newMIB.alloc_cpu_id;
+    num_same_dealloc_cpu += dealloc_cpu_id == newMIB.dealloc_cpu_id;
+    alloc_cpu_id = newMIB.alloc_cpu_id;
+    dealloc_cpu_id = newMIB.dealloc_cpu_id;
+  }
+
+} __attribute__((packed));
+
+} // namespace __memprof
+
+#endif // MEMPROF_MEMINFOBLOCK_H_