[Sanitizers] Move cached allocator_may_return_null flag to sanitizer_allocator

Summary:
Move cached allocator_may_return_null flag to sanitizer_allocator.cc and
provide API to consolidate and unify the behavior of all specific allocators.

Make all sanitizers using CombinedAllocator to follow
AllocatorReturnNullOrDieOnOOM() rules to behave the same way when OOM
happens.

When OOM happens, turn allocator_out_of_memory flag on regardless of
allocator_may_return_null flag value (it used to not to be set when
allocator_may_return_null == true).

release_to_os_interval_ms and rss_limit_exceeded will likely be moved to
sanitizer_allocator.cc too (later).

Reviewers: eugenis

Subscribers: srhines, kubamracek, llvm-commits

Differential Revision: https://reviews.llvm.org/D34310

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@305858 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 16 deletions

diff --git a/lib/scudo/scudo_allocator_combined.h b/lib/scudo/scudo_allocator_combined.h
index c978db55a..21c45897b 100644
--- a/lib/scudo/scudo_allocator_combined.h
+++ b/lib/scudo/scudo_allocator_combined.h
@@ -23,11 +23,10 @@ template <class PrimaryAllocator, class AllocatorCache,
     class SecondaryAllocator>
 class ScudoCombinedAllocator {
  public:
-  void Init(bool AllocatorMayReturnNull, s32 ReleaseToOSIntervalMs) {
+  void Init(s32 ReleaseToOSIntervalMs) {
     Primary.Init(ReleaseToOSIntervalMs);
-    Secondary.Init(AllocatorMayReturnNull);
+    Secondary.Init();
     Stats.Init();
-    atomic_store_relaxed(&MayReturnNull, AllocatorMayReturnNull);
   }
 
   void *Allocate(AllocatorCache *Cache, uptr Size, uptr Alignment,
@@ -37,18 +36,6 @@ class ScudoCombinedAllocator {
     return Secondary.Allocate(&Stats, Size, Alignment);
   }
 
-  void *ReturnNullOrDieOnBadRequest() {
-    if (atomic_load_relaxed(&MayReturnNull))
-      return nullptr;
-    ReportAllocatorCannotReturnNull(false);
-  }
-
-  void *ReturnNullOrDieOnOOM() {
-    if (atomic_load_relaxed(&MayReturnNull))
-      return nullptr;
-    ReportAllocatorCannotReturnNull(true);
-  }
-
   void Deallocate(AllocatorCache *Cache, void *Ptr, bool FromPrimary) {
     if (FromPrimary)
       Cache->Deallocate(&Primary, Primary.GetSizeClass(Ptr), Ptr);
@@ -78,7 +65,6 @@ class ScudoCombinedAllocator {
   PrimaryAllocator Primary;
   SecondaryAllocator Secondary;
   AllocatorGlobalStats Stats;
-  atomic_uint8_t MayReturnNull;
 };
 
 #endif  // SCUDO_ALLOCATOR_COMBINED_H_