[sanitizer] Add facility to print the full StackDepot

Split out of D87120 (memory profiler). Added unit testing of the new
printing facility.

Differential Revision: https://reviews.llvm.org/D87792

Author: teresajohnson

compiler-rt/lib/sanitizer_common/sanitizer_stackdepot.cpp

@@ -115,6 +115,12 @@ void StackDepotUnlockAll() {
   theDepot.UnlockAll();
 }
 
+void StackDepotPrintAll() {
+#if !SANITIZER_GO
+  theDepot.PrintAll();
+#endif
+}
+
 bool StackDepotReverseMap::IdDescPair::IdComparator(
     const StackDepotReverseMap::IdDescPair &a,
     const StackDepotReverseMap::IdDescPair &b) {

compiler-rt/lib/sanitizer_common/sanitizer_stackdepot.h

@@ -41,6 +41,7 @@ StackTrace StackDepotGet(u32 id);
 
 void StackDepotLockAll();
 void StackDepotUnlockAll();
+void StackDepotPrintAll();
 
 // Instantiating this class creates a snapshot of StackDepot which can be
 // efficiently queried with StackDepotGet(). You can use it concurrently with

compiler-rt/lib/sanitizer_common/sanitizer_stackdepotbase.h

@@ -13,9 +13,11 @@
 #ifndef SANITIZER_STACKDEPOTBASE_H
 #define SANITIZER_STACKDEPOTBASE_H
 
+#include <stdio.h>
+
+#include "sanitizer_atomic.h"
 #include "sanitizer_internal_defs.h"
 #include "sanitizer_mutex.h"
-#include "sanitizer_atomic.h"
 #include "sanitizer_persistent_allocator.h"
 
 namespace __sanitizer {
@@ -34,6 +36,7 @@ class StackDepotBase {
 
   void LockAll();
   void UnlockAll();
+  void PrintAll();
 
  private:
   static Node *find(Node *s, args_type args, u32 hash);
@@ -172,6 +175,21 @@ void StackDepotBase<Node, kReservedBits, kTabSizeLog>::UnlockAll() {
   }
 }
 
+template <class Node, int kReservedBits, int kTabSizeLog>
+void StackDepotBase<Node, kReservedBits, kTabSizeLog>::PrintAll() {
+  for (int i = 0; i < kTabSize; ++i) {
+    atomic_uintptr_t *p = &tab[i];
+    lock(p);
+    uptr v = atomic_load(p, memory_order_relaxed);
+    Node *s = (Node *)(v & ~1UL);
+    for (; s; s = s->link) {
+      Printf("Stack for id %u:\n", s->id);
+      s->load().Print();
+    }
+    unlock(p, s);
+  }
+}
+
 } // namespace __sanitizer
 
 #endif // SANITIZER_STACKDEPOTBASE_H

compiler-rt/lib/sanitizer_common/tests/sanitizer_stackdepot_test.cpp

@@ -64,6 +64,20 @@ TEST(SanitizerCommon, StackDepotSeveral) {
   EXPECT_NE(i1, i2);
 }
 
+TEST(SanitizerCommon, StackDepotPrint) {
+  uptr array1[] = {1, 2, 3, 4, 7};
+  StackTrace s1(array1, ARRAY_SIZE(array1));
+  u32 i1 = StackDepotPut(s1);
+  uptr array2[] = {1, 2, 3, 4, 8, 9};
+  StackTrace s2(array2, ARRAY_SIZE(array2));
+  u32 i2 = StackDepotPut(s2);
+  EXPECT_NE(i1, i2);
+  EXPECT_EXIT(
+      (StackDepotPrintAll(), exit(0)), ::testing::ExitedWithCode(0),
+      "Stack for id .*#0 0x0.*#1 0x1.*#2 0x2.*#3 0x3.*#4 0x6.*Stack for id "
+      ".*#0 0x0.*#1 0x1.*#2 0x2.*#3 0x3.*#4 0x7.*#5 0x8.*");
+}
+
 TEST(SanitizerCommon, StackDepotReverseMap) {
   uptr array1[] = {1, 2, 3, 4, 5};
   uptr array2[] = {7, 1, 3, 0};