1 files changed, 236 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/scudo/standalone/common.h b/contrib/llvm-project/compiler-rt/lib/scudo/standalone/common.h
new file mode 100644
index 000000000000..151fbd317e74
--- /dev/null
+++ b/contrib/llvm-project/compiler-rt/lib/scudo/standalone/common.h
@@ -0,0 +1,236 @@
+//===-- common.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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SCUDO_COMMON_H_
+#define SCUDO_COMMON_H_
+
+#include "internal_defs.h"
+
+#include "fuchsia.h"
+#include "linux.h"
+#include "trusty.h"
+
+#include <stddef.h>
+#include <string.h>
+#include <unistd.h>
+
+namespace scudo {
+
+template <class Dest, class Source> inline Dest bit_cast(const Source &S) {
+  static_assert(sizeof(Dest) == sizeof(Source), "");
+  Dest D;
+  memcpy(&D, &S, sizeof(D));
+  return D;
+}
+
+inline constexpr bool isPowerOfTwo(uptr X) {
+  if (X == 0)
+    return false;
+  return (X & (X - 1)) == 0;
+}
+
+inline constexpr uptr roundUp(uptr X, uptr Boundary) {
+  DCHECK(isPowerOfTwo(Boundary));
+  return (X + Boundary - 1) & ~(Boundary - 1);
+}
+inline constexpr uptr roundUpSlow(uptr X, uptr Boundary) {
+  return ((X + Boundary - 1) / Boundary) * Boundary;
+}
+
+inline constexpr uptr roundDown(uptr X, uptr Boundary) {
+  DCHECK(isPowerOfTwo(Boundary));
+  return X & ~(Boundary - 1);
+}
+inline constexpr uptr roundDownSlow(uptr X, uptr Boundary) {
+  return (X / Boundary) * Boundary;
+}
+
+inline constexpr bool isAligned(uptr X, uptr Alignment) {
+  DCHECK(isPowerOfTwo(Alignment));
+  return (X & (Alignment - 1)) == 0;
+}
+inline constexpr bool isAlignedSlow(uptr X, uptr Alignment) {
+  return X % Alignment == 0;
+}
+
+template <class T> constexpr T Min(T A, T B) { return A < B ? A : B; }
+
+template <class T> constexpr T Max(T A, T B) { return A > B ? A : B; }
+
+template <class T> void Swap(T &A, T &B) {
+  T Tmp = A;
+  A = B;
+  B = Tmp;
+}
+
+inline uptr getMostSignificantSetBitIndex(uptr X) {
+  DCHECK_NE(X, 0U);
+  return SCUDO_WORDSIZE - 1U - static_cast<uptr>(__builtin_clzl(X));
+}
+
+inline uptr roundUpPowerOfTwo(uptr Size) {
+  DCHECK(Size);
+  if (isPowerOfTwo(Size))
+    return Size;
+  const uptr Up = getMostSignificantSetBitIndex(Size);
+  DCHECK_LT(Size, (1UL << (Up + 1)));
+  DCHECK_GT(Size, (1UL << Up));
+  return 1UL << (Up + 1);
+}
+
+inline uptr getLeastSignificantSetBitIndex(uptr X) {
+  DCHECK_NE(X, 0U);
+  return static_cast<uptr>(__builtin_ctzl(X));
+}
+
+inline uptr getLog2(uptr X) {
+  DCHECK(isPowerOfTwo(X));
+  return getLeastSignificantSetBitIndex(X);
+}
+
+inline u32 getRandomU32(u32 *State) {
+  // ANSI C linear congruential PRNG (16-bit output).
+  // return (*State = *State * 1103515245 + 12345) >> 16;
+  // XorShift (32-bit output).
+  *State ^= *State << 13;
+  *State ^= *State >> 17;
+  *State ^= *State << 5;
+  return *State;
+}
+
+inline u32 getRandomModN(u32 *State, u32 N) {
+  return getRandomU32(State) % N; // [0, N)
+}
+
+template <typename T> inline void shuffle(T *A, u32 N, u32 *RandState) {
+  if (N <= 1)
+    return;
+  u32 State = *RandState;
+  for (u32 I = N - 1; I > 0; I--)
+    Swap(A[I], A[getRandomModN(&State, I + 1)]);
+  *RandState = State;
+}
+
+inline void computePercentage(uptr Numerator, uptr Denominator, uptr *Integral,
+                              uptr *Fractional) {
+  constexpr uptr Digits = 100;
+  if (Denominator == 0) {
+    *Integral = 100;
+    *Fractional = 0;
+    return;
+  }
+
+  *Integral = Numerator * Digits / Denominator;
+  *Fractional =
+      (((Numerator * Digits) % Denominator) * Digits + Denominator / 2) /
+      Denominator;
+}
+
+// Platform specific functions.
+
+extern uptr PageSizeCached;
+uptr getPageSizeSlow();
+inline uptr getPageSizeCached() {
+#if SCUDO_ANDROID && defined(PAGE_SIZE)
+  // Most Android builds have a build-time constant page size.
+  return PAGE_SIZE;
+#endif
+  if (LIKELY(PageSizeCached))
+    return PageSizeCached;
+  return getPageSizeSlow();
+}
+
+// Returns 0 if the number of CPUs could not be determined.
+u32 getNumberOfCPUs();
+
+const char *getEnv(const char *Name);
+
+u64 getMonotonicTime();
+// Gets the time faster but with less accuracy. Can call getMonotonicTime
+// if no fast version is available.
+u64 getMonotonicTimeFast();
+
+u32 getThreadID();
+
+// Our randomness gathering function is limited to 256 bytes to ensure we get
+// as many bytes as requested, and avoid interruptions (on Linux).
+constexpr uptr MaxRandomLength = 256U;
+bool getRandom(void *Buffer, uptr Length, bool Blocking = false);
+
+// Platform memory mapping functions.
+
+#define MAP_ALLOWNOMEM (1U << 0)
+#define MAP_NOACCESS (1U << 1)
+#define MAP_RESIZABLE (1U << 2)
+#define MAP_MEMTAG (1U << 3)
+#define MAP_PRECOMMIT (1U << 4)
+
+// Our platform memory mapping use is restricted to 3 scenarios:
+// - reserve memory at a random address (MAP_NOACCESS);
+// - commit memory in a previously reserved space;
+// - commit memory at a random address.
+// As such, only a subset of parameters combinations is valid, which is checked
+// by the function implementation. The Data parameter allows to pass opaque
+// platform specific data to the function.
+// Returns nullptr on error or dies if MAP_ALLOWNOMEM is not specified.
+void *map(void *Addr, uptr Size, const char *Name, uptr Flags = 0,
+          MapPlatformData *Data = nullptr);
+
+// Indicates that we are getting rid of the whole mapping, which might have
+// further consequences on Data, depending on the platform.
+#define UNMAP_ALL (1U << 0)
+
+void unmap(void *Addr, uptr Size, uptr Flags = 0,
+           MapPlatformData *Data = nullptr);
+
+void setMemoryPermission(uptr Addr, uptr Size, uptr Flags,
+                         MapPlatformData *Data = nullptr);
+
+void releasePagesToOS(uptr BaseAddress, uptr Offset, uptr Size,
+                      MapPlatformData *Data = nullptr);
+
+// Logging related functions.
+
+void setAbortMessage(const char *Message);
+
+struct BlockInfo {
+  uptr BlockBegin;
+  uptr BlockSize;
+  uptr RegionBegin;
+  uptr RegionEnd;
+};
+
+enum class Option : u8 {
+  ReleaseInterval,      // Release to OS interval in milliseconds.
+  MemtagTuning,         // Whether to tune tagging for UAF or overflow.
+  ThreadDisableMemInit, // Whether to disable automatic heap initialization and,
+                        // where possible, memory tagging, on this thread.
+  MaxCacheEntriesCount, // Maximum number of blocks that can be cached.
+  MaxCacheEntrySize,    // Maximum size of a block that can be cached.
+  MaxTSDsCount,         // Number of usable TSDs for the shared registry.
+};
+
+enum class ReleaseToOS : u8 {
+  Normal, // Follow the normal rules for releasing pages to the OS
+  Force,  // Force release pages to the OS, but avoid cases that take too long.
+  ForceAll, // Force release every page possible regardless of how long it will
+            // take.
+};
+
+constexpr unsigned char PatternFillByte = 0xAB;
+
+enum FillContentsMode {
+  NoFill = 0,
+  ZeroFill = 1,
+  PatternOrZeroFill = 2 // Pattern fill unless the memory is known to be
+                        // zero-initialized already.
+};
+
+} // namespace scudo
+
+#endif // SCUDO_COMMON_H_