Make InternalAlloc/InternalFree in sanitizer runtimes libc-free by switching to a custom allocator.

llvm-svn: 182836

1 files changed, 64 insertions, 0 deletions

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_allocator_internal.h b/compiler-rt/lib/sanitizer_common/sanitizer_allocator_internal.h
new file mode 100644
index 00000000000..5eea5243f93
--- /dev/null
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_allocator_internal.h
@@ -0,0 +1,64 @@
+//===-- sanitizer_allocator_internal.h -------------------------- C++ -----===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This allocator is used inside run-times.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SANITIZER_ALLOCATOR_INTERNAL_H
+#define SANITIZER_ALLOCATOR_INTERNAL_H
+
+#include "sanitizer_allocator.h"
+#include "sanitizer_internal_defs.h"
+
+namespace __sanitizer {
+
+// TODO: Check if we may use even more compact size class map for internal
+// purposes.
+typedef CompactSizeClassMap InternalSizeClassMap;
+
+static const uptr kInternalAllocatorSpace = 0;
+#if SANITIZER_WORDSIZE == 32
+static const u64 kInternalAllocatorSize = (1ULL << 32);
+static const uptr kInternalAllocatorRegionSizeLog = 20;
+#else
+static const u64 kInternalAllocatorSize = (1ULL << 47);
+static const uptr kInternalAllocatorRegionSizeLog = 24;
+#endif
+static const uptr kInternalAllocatorFlatByteMapSize =
+    kInternalAllocatorSize >> kInternalAllocatorRegionSizeLog;
+typedef SizeClassAllocator32<
+    kInternalAllocatorSpace, kInternalAllocatorSize, 16, InternalSizeClassMap,
+    kInternalAllocatorRegionSizeLog,
+    FlatByteMap<kInternalAllocatorFlatByteMapSize> > PrimaryInternalAllocator;
+
+typedef SizeClassAllocatorLocalCache<PrimaryInternalAllocator>
+    InternalAllocatorCache;
+
+// We don't want our internal allocator to do any map/unmap operations.
+struct CrashOnMapUnmap {
+  void OnMap(uptr p, uptr size) const {
+    CHECK(0 && "Unexpected mmap in InternalAllocator!");
+  }
+  void OnUnmap(uptr p, uptr size) const {
+    CHECK(0 && "Unexpected unmap in InternalAllocator!");
+  }
+};
+
+typedef CombinedAllocator<PrimaryInternalAllocator, InternalAllocatorCache,
+                          LargeMmapAllocator<CrashOnMapUnmap> >
+    InternalAllocator;
+
+void *InternalAlloc(uptr size, InternalAllocatorCache *cache = 0);
+void InternalFree(void *p, InternalAllocatorCache *cache = 0);
+InternalAllocator *internal_allocator();
+
+}  // namespace __sanitizer
+
+#endif  // SANITIZER_ALLOCATOR_INTERNAL_H