[LSan] Add dynamic loading support for LSan library

The LSan library has very big static TLS section

Problem:
  - LSan library could not be loaded dynamically because it had a very
    big static TLS section.
        AllocatorCache: ~15KB for 32bit
                        ~53KB for 64bit
Solution:
  - Store in the TLS section only a pointer to the AllocatorCache and
    dynamically allocate memory for it.

Change-Id: I6e90e6682e277c90825938f5732867b6564d62b4
Signed-off-by: Vyacheslav Cherkashin <v.cherkashin@samsung.com>

1 files changed, 10 insertions, 2 deletions

diff --git a/libsanitizer/lsan/lsan_linux.cpp b/libsanitizer/lsan/lsan_linux.cpp
index 5074cee1296..933bc35d190 100644
--- a/libsanitizer/lsan/lsan_linux.cpp
+++ b/libsanitizer/lsan/lsan_linux.cpp
@@ -14,6 +14,7 @@
 
 #if SANITIZER_LINUX || SANITIZER_NETBSD || SANITIZER_FUCHSIA
 
+#  include "sanitizer_common/sanitizer_allocator_internal.h"
 #  include "lsan_allocator.h"
 #  include "lsan_thread.h"
 
@@ -23,8 +24,15 @@ static THREADLOCAL ThreadContextLsanBase *current_thread = nullptr;
 ThreadContextLsanBase *GetCurrentThread() { return current_thread; }
 void SetCurrentThread(ThreadContextLsanBase *tctx) { current_thread = tctx; }
 
-static THREADLOCAL AllocatorCache allocator_cache;
-AllocatorCache *GetAllocatorCache() { return &allocator_cache; }
+static THREADLOCAL AllocatorCache *allocator_cache;
+AllocatorCache *GetAllocatorCache() {
+  if (UNLIKELY(allocator_cache == nullptr)) {
+    // We will not release the memory because the library is not unloaded.
+    allocator_cache = (AllocatorCache *)InternalAlloc(sizeof(*allocator_cache));
+    *allocator_cache = AllocatorCache();
+  }
+  return allocator_cache;
+}
 
 void ReplaceSystemMalloc() {}