[msan] MemorySanitizer runtime.
Initial commit of the MemorySanitizer runtime library.
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@169858 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/msan/msan_allocator.cc b/lib/msan/msan_allocator.cc
new file mode 100644
index 0000000..5d865c3
--- /dev/null
+++ b/lib/msan/msan_allocator.cc
@@ -0,0 +1,107 @@
+//===-- msan_allocator.cc --------------------------- ---------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of MemorySanitizer.
+//
+// MemorySanitizer allocator.
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_common/sanitizer_allocator.h"
+#include "sanitizer_common/sanitizer_stackdepot.h"
+#include "msan.h"
+
+namespace __msan {
+
+struct Metadata {
+ uptr requested_size;
+};
+
+static const uptr kAllocatorSpace = 0x600000000000ULL;
+static const uptr kAllocatorSize = 0x80000000000; // 8T.
+static const uptr kMetadataSize = sizeof(Metadata);
+
+typedef SizeClassAllocator64<kAllocatorSpace, kAllocatorSize, kMetadataSize,
+ DefaultSizeClassMap> PrimaryAllocator;
+typedef SizeClassAllocatorLocalCache<PrimaryAllocator> AllocatorCache;
+typedef LargeMmapAllocator SecondaryAllocator;
+typedef CombinedAllocator<PrimaryAllocator, AllocatorCache,
+ SecondaryAllocator> Allocator;
+
+static THREADLOCAL AllocatorCache cache;
+static Allocator allocator;
+
+static int inited = 0;
+
+static inline void Init() {
+ if (inited) return;
+ __msan_init();
+ inited = true; // this must happen before any threads are created.
+ allocator.Init();
+}
+
+static void *MsanAllocate(StackTrace *stack, uptr size,
+ uptr alignment, bool zeroise) {
+ Init();
+ void *res = allocator.Allocate(&cache, size, alignment, false);
+ Metadata *meta = reinterpret_cast<Metadata*>(allocator.GetMetaData(res));
+ meta->requested_size = size;
+ if (zeroise)
+ __msan_clear_and_unpoison(res, size);
+ else if (flags()->poison_in_malloc)
+ __msan_poison(res, size);
+ if (__msan_get_track_origins()) {
+ u32 stack_id = StackDepotPut(stack->trace, stack->size);
+ CHECK(stack_id);
+ CHECK_EQ((stack_id >> 31), 0); // Higher bit is occupied by stack origins.
+ __msan_set_origin(res, size, stack_id);
+ }
+ return res;
+}
+
+void MsanDeallocate(void *p) {
+ CHECK(p);
+ Init();
+ Metadata *meta = reinterpret_cast<Metadata*>(allocator.GetMetaData(p));
+ uptr size = meta->requested_size;
+ // This memory will not be reused by anyone else, so we are free to keep it
+ // poisoned.
+ __msan_poison(p, size);
+ if (__msan_get_track_origins())
+ __msan_set_origin(p, size, -1);
+ allocator.Deallocate(&cache, p);
+}
+
+void *MsanReallocate(StackTrace *stack, void *old_p, uptr new_size,
+ uptr alignment, bool zeroise) {
+ if (!old_p)
+ return MsanAllocate(stack, new_size, alignment, zeroise);
+ if (!new_size) {
+ MsanDeallocate(old_p);
+ return 0;
+ }
+ Metadata *meta = reinterpret_cast<Metadata*>(allocator.GetMetaData(old_p));
+ uptr old_size = meta->requested_size;
+ uptr actually_allocated_size = allocator.GetActuallyAllocatedSize(old_p);
+ if (new_size <= actually_allocated_size) {
+ // We are not reallocating here.
+ meta->requested_size = new_size;
+ if (new_size > old_size)
+ __msan_poison((char*)old_p + old_size, new_size - old_size);
+ return old_p;
+ }
+ uptr memcpy_size = Min(new_size, old_size);
+ void *new_p = MsanAllocate(stack, new_size, alignment, zeroise);
+ // Printf("realloc: old_size %zd new_size %zd\n", old_size, new_size);
+ if (new_p)
+ __msan_memcpy(new_p, old_p, memcpy_size);
+ MsanDeallocate(old_p);
+ return new_p;
+}
+
+} // namespace __msan
