# HG changeset patch
# User mdoerr
# Date 1562858615 -7200
#      Thu Jul 11 17:23:35 2019 +0200
# Node ID ea0e02a1e75cd0d50c31e9fc1f0f489c2d48ddb1
# Parent  107ebf94ddccd9ad4507d64b8ba5cd319b85814e
8227597: [fastdbg build] Arena::inc_bytes_allocated should get inlined
Reviewed-by:

diff --git a/src/hotspot/share/memory/allocation.inline.hpp b/src/hotspot/share/memory/allocation.inline.hpp
--- a/src/hotspot/share/memory/allocation.inline.hpp
+++ b/src/hotspot/share/memory/allocation.inline.hpp
@@ -34,17 +34,10 @@
 // Explicit C-heap memory management
 
 #ifndef PRODUCT
-// Increments unsigned long value for statistics (not atomic on MP).
+// Increments unsigned long value for statistics (not atomic on MP, but avoids word-tearing on 32 bit).
 inline void inc_stat_counter(volatile julong* dest, julong add_value) {
-#if defined(SPARC) || defined(X86)
-  // Sparc and X86 have atomic jlong (8 bytes) instructions
   julong value = Atomic::load(dest);
-  value += add_value;
-  Atomic::store(value, dest);
-#else
-  // possible word-tearing during load/store
-  *dest += add_value;
-#endif
+  Atomic::store(value + add_value, dest);
 }
 #endif
 
diff --git a/src/hotspot/share/memory/arena.cpp b/src/hotspot/share/memory/arena.cpp
--- a/src/hotspot/share/memory/arena.cpp
+++ b/src/hotspot/share/memory/arena.cpp
@@ -477,8 +477,6 @@
 
 julong Arena::_bytes_allocated = 0;
 
-void Arena::inc_bytes_allocated(size_t x) { inc_stat_counter(&_bytes_allocated, x); }
-
 // debugging code
 inline void Arena::free_all(char** start, char** end) {
   for (char** p = start; p < end; p++) if (*p) os::free(*p);
diff --git a/src/hotspot/share/memory/arena.hpp b/src/hotspot/share/memory/arena.hpp
--- a/src/hotspot/share/memory/arena.hpp
+++ b/src/hotspot/share/memory/arena.hpp
@@ -26,6 +26,7 @@
 #define SHARE_MEMORY_ARENA_HPP
 
 #include "memory/allocation.hpp"
+#include "runtime/atomic.hpp"
 #include "runtime/globals.hpp"
 #include "utilities/globalDefinitions.hpp"
 
@@ -106,11 +107,18 @@
   void* grow(size_t x, AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
   size_t _size_in_bytes;        // Size of arena (used for native memory tracking)
 
-  NOT_PRODUCT(static julong _bytes_allocated;) // total #bytes allocated since start
+#ifndef PRODUCT
+  static julong _bytes_allocated; // total #bytes allocated since start
+  // Inlinable increment function (not atomic on MP, but avoids word-tearing on 32 bit)
+  void inc_bytes_allocated(size_t x) {
+    julong value = Atomic::load(&_bytes_allocated);
+    Atomic::store(value + x, &_bytes_allocated);
+  }
+#endif
+
   friend class AllocStats;
   debug_only(void* malloc(size_t size);)
   debug_only(void* internal_malloc_4(size_t x);)
-  NOT_PRODUCT(void inc_bytes_allocated(size_t x);)
 
   void signal_out_of_memory(size_t request, const char* whence) const;