Index: lib/sanitizer_common/sanitizer_coverage_libcdep.cc
===================================================================
--- lib/sanitizer_common/sanitizer_coverage_libcdep.cc
+++ lib/sanitizer_common/sanitizer_coverage_libcdep.cc
@@ -109,6 +109,8 @@
   uptr *data();
   uptr size();
 
+  uptr *stack() const { return pc_stack; }
+
  private:
   void DirectOpen();
   void UpdateModuleNameVec(uptr caller_pc, uptr range_beg, uptr range_end);
@@ -133,6 +135,8 @@
   // Descriptor of the file mapped pc array.
   fd_t pc_fd;
 
+  uptr *pc_stack;
+
   // Vector of coverage guard arrays, protected by mu.
   InternalMmapVectorNoCtor<s32*> guard_array_vec;
 
@@ -209,6 +213,9 @@
     atomic_store(&pc_array_size, kPcArrayMaxSize, memory_order_relaxed);
   }
 
+  pc_stack = reinterpret_cast<uptr *>(
+      MmapNoReserveOrDie(sizeof(uptr) * kPcArrayMaxSize, "CovInit::pc_stack"));
+
   cc_array = reinterpret_cast<uptr **>(MmapNoReserveOrDie(
       sizeof(uptr *) * kCcArrayMaxSize, "CovInit::cc_array"));
   atomic_store(&cc_array_size, kCcArrayMaxSize, memory_order_relaxed);
@@ -246,6 +253,10 @@
     UnmapOrDie(cc_array, sizeof(uptr *) * kCcArrayMaxSize);
     cc_array = nullptr;
   }
+  if (pc_stack) {
+    UnmapOrDie(pc_stack, sizeof(uptr) * kPcArrayMaxSize);
+    pc_stack = nullptr;
+  }
   if (tr_event_array) {
     UnmapOrDie(tr_event_array,
                sizeof(tr_event_array[0]) * kTrEventArrayMaxSize +
@@ -410,10 +421,12 @@
   uptr idx = -guard_value - 1;
   if (idx >= atomic_load(&pc_array_index, memory_order_acquire))
     return;  // May happen after fork when pc_array_index becomes 0.
+
   CHECK_LT(idx * sizeof(uptr),
            atomic_load(&pc_array_size, memory_order_acquire));
   uptr counter = atomic_fetch_add(&coverage_counter, 1, memory_order_relaxed);
   pc_array[idx] = BundlePcAndCounter(pc, counter);
+  pc_stack[counter] = pc;
 }
 
 // Registers a pair caller=>callee.
@@ -942,6 +955,10 @@
   *data = coverage_data.data();
   return coverage_data.size();
 }
+SANITIZER_INTERFACE_ATTRIBUTE
+void __sanitizer_get_coverage_stack(uptr **data) {
+  *data = coverage_data.stack();
+}
 
 SANITIZER_INTERFACE_ATTRIBUTE
 uptr __sanitizer_get_number_of_counters() {