add sanitizers dependencies

1 files changed, 192 insertions, 0 deletions

diff --git a/contrib/libs/clang14-rt/lib/scudo/scudo_allocator_secondary.h b/contrib/libs/clang14-rt/lib/scudo/scudo_allocator_secondary.h
new file mode 100644
index 0000000000..80198c4aeb
--- /dev/null
+++ b/contrib/libs/clang14-rt/lib/scudo/scudo_allocator_secondary.h
@@ -0,0 +1,192 @@
+//===-- scudo_allocator_secondary.h -----------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// Scudo Secondary Allocator.
+/// This services allocation that are too large to be serviced by the Primary
+/// Allocator. It is directly backed by the memory mapping functions of the
+/// operating system.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef SCUDO_ALLOCATOR_SECONDARY_H_
+#define SCUDO_ALLOCATOR_SECONDARY_H_
+
+#ifndef SCUDO_ALLOCATOR_H_
+# error "This file must be included inside scudo_allocator.h."
+#endif
+
+// Secondary backed allocations are standalone chunks that contain extra
+// information stored in a LargeChunk::Header prior to the frontend's header.
+//
+// The secondary takes care of alignment requirements (so that it can release
+// unnecessary pages in the rare event of larger alignments), and as such must
+// know about the frontend's header size.
+//
+// Since Windows doesn't support partial releasing of a reserved memory region,
+// we have to keep track of both the reserved and the committed memory.
+//
+// The resulting chunk resembles the following:
+//
+//   +--------------------+
+//   | Guard page(s)      |
+//   +--------------------+
+//   | Unused space*      |
+//   +--------------------+
+//   | LargeChunk::Header |
+//   +--------------------+
+//   | {Unp,P}ackedHeader |
+//   +--------------------+
+//   | Data (aligned)     |
+//   +--------------------+
+//   | Unused space**     |
+//   +--------------------+
+//   | Guard page(s)      |
+//   +--------------------+
+
+namespace LargeChunk {
+struct Header {
+  ReservedAddressRange StoredRange;
+  uptr CommittedSize;
+  uptr Size;
+};
+constexpr uptr getHeaderSize() {
+  return RoundUpTo(sizeof(Header), MinAlignment);
+}
+static Header *getHeader(uptr Ptr) {
+  return reinterpret_cast<Header *>(Ptr - getHeaderSize());
+}
+static Header *getHeader(const void *Ptr) {
+  return getHeader(reinterpret_cast<uptr>(Ptr));
+}
+}  // namespace LargeChunk
+
+class LargeMmapAllocator {
+ public:
+  void Init() {
+    internal_memset(this, 0, sizeof(*this));
+  }
+
+  void *Allocate(AllocatorStats *Stats, uptr Size, uptr Alignment) {
+    const uptr UserSize = Size - Chunk::getHeaderSize();
+    // The Scudo frontend prevents us from allocating more than
+    // MaxAllowedMallocSize, so integer overflow checks would be superfluous.
+    uptr ReservedSize = Size + LargeChunk::getHeaderSize();
+    if (UNLIKELY(Alignment > MinAlignment))
+      ReservedSize += Alignment;
+    const uptr PageSize = GetPageSizeCached();
+    ReservedSize = RoundUpTo(ReservedSize, PageSize);
+    // Account for 2 guard pages, one before and one after the chunk.
+    ReservedSize += 2 * PageSize;
+
+    ReservedAddressRange AddressRange;
+    uptr ReservedBeg = AddressRange.Init(ReservedSize, SecondaryAllocatorName);
+    if (UNLIKELY(ReservedBeg == ~static_cast<uptr>(0)))
+      return nullptr;
+    // A page-aligned pointer is assumed after that, so check it now.
+    DCHECK(IsAligned(ReservedBeg, PageSize));
+    uptr ReservedEnd = ReservedBeg + ReservedSize;
+    // The beginning of the user area for that allocation comes after the
+    // initial guard page, and both headers. This is the pointer that has to
+    // abide by alignment requirements.
+    uptr CommittedBeg = ReservedBeg + PageSize;
+    uptr UserBeg = CommittedBeg + HeadersSize;
+    uptr UserEnd = UserBeg + UserSize;
+    uptr CommittedEnd = RoundUpTo(UserEnd, PageSize);
+
+    // In the rare event of larger alignments, we will attempt to fit the mmap
+    // area better and unmap extraneous memory. This will also ensure that the
+    // offset and unused bytes field of the header stay small.
+    if (UNLIKELY(Alignment > MinAlignment)) {
+      if (!IsAligned(UserBeg, Alignment)) {
+        UserBeg = RoundUpTo(UserBeg, Alignment);
+        CommittedBeg = RoundDownTo(UserBeg - HeadersSize, PageSize);
+        const uptr NewReservedBeg = CommittedBeg - PageSize;
+        DCHECK_GE(NewReservedBeg, ReservedBeg);
+        if (!SANITIZER_WINDOWS && NewReservedBeg != ReservedBeg) {
+          AddressRange.Unmap(ReservedBeg, NewReservedBeg - ReservedBeg);
+          ReservedBeg = NewReservedBeg;
+        }
+        UserEnd = UserBeg + UserSize;
+        CommittedEnd = RoundUpTo(UserEnd, PageSize);
+      }
+      const uptr NewReservedEnd = CommittedEnd + PageSize;
+      DCHECK_LE(NewReservedEnd, ReservedEnd);
+      if (!SANITIZER_WINDOWS && NewReservedEnd != ReservedEnd) {
+        AddressRange.Unmap(NewReservedEnd, ReservedEnd - NewReservedEnd);
+        ReservedEnd = NewReservedEnd;
+      }
+    }
+
+    DCHECK_LE(UserEnd, CommittedEnd);
+    const uptr CommittedSize = CommittedEnd - CommittedBeg;
+    // Actually mmap the memory, preserving the guard pages on either sides.
+    CHECK_EQ(CommittedBeg, AddressRange.Map(CommittedBeg, CommittedSize));
+    const uptr Ptr = UserBeg - Chunk::getHeaderSize();
+    LargeChunk::Header *H = LargeChunk::getHeader(Ptr);
+    H->StoredRange = AddressRange;
+    H->Size = CommittedEnd - Ptr;
+    H->CommittedSize = CommittedSize;
+
+    // The primary adds the whole class size to the stats when allocating a
+    // chunk, so we will do something similar here. But we will not account for
+    // the guard pages.
+    {
+      SpinMutexLock l(&StatsMutex);
+      Stats->Add(AllocatorStatAllocated, CommittedSize);
+      Stats->Add(AllocatorStatMapped, CommittedSize);
+      AllocatedBytes += CommittedSize;
+      if (LargestSize < CommittedSize)
+        LargestSize = CommittedSize;
+      NumberOfAllocs++;
+    }
+
+    return reinterpret_cast<void *>(Ptr);
+  }
+
+  void Deallocate(AllocatorStats *Stats, void *Ptr) {
+    LargeChunk::Header *H = LargeChunk::getHeader(Ptr);
+    // Since we're unmapping the entirety of where the ReservedAddressRange
+    // actually is, copy onto the stack.
+    ReservedAddressRange AddressRange = H->StoredRange;
+    const uptr Size = H->CommittedSize;
+    {
+      SpinMutexLock l(&StatsMutex);
+      Stats->Sub(AllocatorStatAllocated, Size);
+      Stats->Sub(AllocatorStatMapped, Size);
+      FreedBytes += Size;
+      NumberOfFrees++;
+    }
+    AddressRange.Unmap(reinterpret_cast<uptr>(AddressRange.base()),
+                       AddressRange.size());
+  }
+
+  static uptr GetActuallyAllocatedSize(void *Ptr) {
+    return LargeChunk::getHeader(Ptr)->Size;
+  }
+
+  void PrintStats() {
+    Printf("Stats: LargeMmapAllocator: allocated %zd times (%zd K), "
+           "freed %zd times (%zd K), remains %zd (%zd K) max %zd M\n",
+           NumberOfAllocs, AllocatedBytes >> 10, NumberOfFrees,
+           FreedBytes >> 10, NumberOfAllocs - NumberOfFrees,
+           (AllocatedBytes - FreedBytes) >> 10, LargestSize >> 20);
+  }
+
+ private:
+  static constexpr uptr HeadersSize =
+      LargeChunk::getHeaderSize() + Chunk::getHeaderSize();
+
+  StaticSpinMutex StatsMutex;
+  u32 NumberOfAllocs;
+  u32 NumberOfFrees;
+  uptr AllocatedBytes;
+  uptr FreedBytes;
+  uptr LargestSize;
+};
+
+#endif  // SCUDO_ALLOCATOR_SECONDARY_H_