1 files changed, 239 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/lsan/lsan_common_mac.cpp b/contrib/llvm-project/compiler-rt/lib/lsan/lsan_common_mac.cpp
new file mode 100644
index 000000000000..4e5198979b95
--- /dev/null
+++ b/contrib/llvm-project/compiler-rt/lib/lsan/lsan_common_mac.cpp
@@ -0,0 +1,239 @@
+//=-- lsan_common_mac.cpp -------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of LeakSanitizer.
+// Implementation of common leak checking functionality. Darwin-specific code.
+//
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_common/sanitizer_platform.h"
+#include "sanitizer_common/sanitizer_libc.h"
+#include "lsan_common.h"
+
+#if CAN_SANITIZE_LEAKS && SANITIZER_APPLE
+
+#  include <mach/mach.h>
+#  include <mach/vm_statistics.h>
+#  include <pthread.h>
+
+#  include "lsan_allocator.h"
+#  include "sanitizer_common/sanitizer_allocator_internal.h"
+namespace __lsan {
+
+class ThreadContextLsanBase;
+
+enum class SeenRegion {
+  None = 0,
+  AllocOnce = 1 << 0,
+  LibDispatch = 1 << 1,
+  Foundation = 1 << 2,
+  All = AllocOnce | LibDispatch | Foundation
+};
+
+inline SeenRegion operator|(SeenRegion left, SeenRegion right) {
+  return static_cast<SeenRegion>(static_cast<int>(left) |
+                                 static_cast<int>(right));
+}
+
+inline SeenRegion &operator|=(SeenRegion &left, const SeenRegion &right) {
+  left = left | right;
+  return left;
+}
+
+struct RegionScanState {
+  SeenRegion seen_regions = SeenRegion::None;
+  bool in_libdispatch = false;
+};
+
+typedef struct {
+  int disable_counter;
+  ThreadContextLsanBase *current_thread;
+  AllocatorCache cache;
+} thread_local_data_t;
+
+static pthread_key_t key;
+static pthread_once_t key_once = PTHREAD_ONCE_INIT;
+
+// The main thread destructor requires the current thread,
+// so we can't destroy it until it's been used and reset.
+void restore_tid_data(void *ptr) {
+  thread_local_data_t *data = (thread_local_data_t *)ptr;
+  if (data->current_thread)
+    pthread_setspecific(key, data);
+}
+
+static void make_tls_key() {
+  CHECK_EQ(pthread_key_create(&key, restore_tid_data), 0);
+}
+
+static thread_local_data_t *get_tls_val(bool alloc) {
+  pthread_once(&key_once, make_tls_key);
+
+  thread_local_data_t *ptr = (thread_local_data_t *)pthread_getspecific(key);
+  if (ptr == NULL && alloc) {
+    ptr = (thread_local_data_t *)InternalAlloc(sizeof(*ptr));
+    ptr->disable_counter = 0;
+    ptr->current_thread = nullptr;
+    ptr->cache = AllocatorCache();
+    pthread_setspecific(key, ptr);
+  }
+
+  return ptr;
+}
+
+bool DisabledInThisThread() {
+  thread_local_data_t *data = get_tls_val(false);
+  return data ? data->disable_counter > 0 : false;
+}
+
+void DisableInThisThread() { ++get_tls_val(true)->disable_counter; }
+
+void EnableInThisThread() {
+  int *disable_counter = &get_tls_val(true)->disable_counter;
+  if (*disable_counter == 0) {
+    DisableCounterUnderflow();
+  }
+  --*disable_counter;
+}
+
+ThreadContextLsanBase *GetCurrentThread() {
+  thread_local_data_t *data = get_tls_val(false);
+  return data ? data->current_thread : nullptr;
+}
+
+void SetCurrentThread(ThreadContextLsanBase *tctx) {
+  get_tls_val(true)->current_thread = tctx;
+}
+
+AllocatorCache *GetAllocatorCache() { return &get_tls_val(true)->cache; }
+
+LoadedModule *GetLinker() { return nullptr; }
+
+// Required on Linux for initialization of TLS behavior, but should not be
+// required on Darwin.
+void InitializePlatformSpecificModules() {}
+
+// Sections which can't contain contain global pointers. This list errs on the
+// side of caution to avoid false positives, at the expense of performance.
+//
+// Other potentially safe sections include:
+// __all_image_info, __crash_info, __const, __got, __interpose, __objc_msg_break
+//
+// Sections which definitely cannot be included here are:
+// __objc_data, __objc_const, __data, __bss, __common, __thread_data,
+// __thread_bss, __thread_vars, __objc_opt_rw, __objc_opt_ptrs
+static const char *kSkippedSecNames[] = {
+    "__cfstring",       "__la_symbol_ptr",  "__mod_init_func",
+    "__mod_term_func",  "__nl_symbol_ptr",  "__objc_classlist",
+    "__objc_classrefs", "__objc_imageinfo", "__objc_nlclslist",
+    "__objc_protolist", "__objc_selrefs",   "__objc_superrefs"};
+
+// Scans global variables for heap pointers.
+void ProcessGlobalRegions(Frontier *frontier) {
+  for (auto name : kSkippedSecNames)
+    CHECK(internal_strnlen(name, kMaxSegName + 1) <= kMaxSegName);
+
+  MemoryMappingLayout memory_mapping(false);
+  InternalMmapVector<LoadedModule> modules;
+  modules.reserve(128);
+  memory_mapping.DumpListOfModules(&modules);
+  for (uptr i = 0; i < modules.size(); ++i) {
+    // Even when global scanning is disabled, we still need to scan
+    // system libraries for stashed pointers
+    if (!flags()->use_globals && modules[i].instrumented()) continue;
+
+    for (const __sanitizer::LoadedModule::AddressRange &range :
+         modules[i].ranges()) {
+      // Sections storing global variables are writable and non-executable
+      if (range.executable || !range.writable) continue;
+
+      for (auto name : kSkippedSecNames) {
+        if (!internal_strcmp(range.name, name)) continue;
+      }
+
+      ScanGlobalRange(range.beg, range.end, frontier);
+    }
+  }
+}
+
+void ProcessPlatformSpecificAllocations(Frontier *frontier) {
+  vm_address_t address = 0;
+  kern_return_t err = KERN_SUCCESS;
+
+  InternalMmapVector<Region> mapped_regions;
+  bool use_root_regions = flags()->use_root_regions && HasRootRegions();
+
+  RegionScanState scan_state;
+  while (err == KERN_SUCCESS) {
+    vm_size_t size = 0;
+    unsigned depth = 1;
+    struct vm_region_submap_info_64 info;
+    mach_msg_type_number_t count = VM_REGION_SUBMAP_INFO_COUNT_64;
+    err = vm_region_recurse_64(mach_task_self(), &address, &size, &depth,
+                               (vm_region_info_t)&info, &count);
+
+    uptr end_address = address + size;
+    if (info.user_tag == VM_MEMORY_OS_ALLOC_ONCE) {
+      // libxpc stashes some pointers in the Kernel Alloc Once page,
+      // make sure not to report those as leaks.
+      scan_state.seen_regions |= SeenRegion::AllocOnce;
+      ScanRangeForPointers(address, end_address, frontier, "GLOBAL",
+                           kReachable);
+    } else if (info.user_tag == VM_MEMORY_FOUNDATION) {
+      // Objective-C block trampolines use the Foundation region.
+      scan_state.seen_regions |= SeenRegion::Foundation;
+      ScanRangeForPointers(address, end_address, frontier, "GLOBAL",
+                           kReachable);
+    } else if (info.user_tag == VM_MEMORY_LIBDISPATCH) {
+      // Dispatch continuations use the libdispatch region. Empirically, there
+      // can be more than one region with this tag, so we'll optimistically
+      // assume that they're continguous. Otherwise, we would need to scan every
+      // region to ensure we find them all.
+      scan_state.in_libdispatch = true;
+      ScanRangeForPointers(address, end_address, frontier, "GLOBAL",
+                           kReachable);
+    } else if (scan_state.in_libdispatch) {
+      scan_state.seen_regions |= SeenRegion::LibDispatch;
+      scan_state.in_libdispatch = false;
+    }
+
+    // Recursing over the full memory map is very slow, break out
+    // early if we don't need the full iteration.
+    if (scan_state.seen_regions == SeenRegion::All && !use_root_regions) {
+      break;
+    }
+
+    // This additional root region scan is required on Darwin in order to
+    // detect root regions contained within mmap'd memory regions, because
+    // the Darwin implementation of sanitizer_procmaps traverses images
+    // as loaded by dyld, and not the complete set of all memory regions.
+    //
+    // TODO(fjricci) - remove this once sanitizer_procmaps_mac has the same
+    // behavior as sanitizer_procmaps_linux and traverses all memory regions
+    if (use_root_regions && (info.protection & kProtectionRead))
+      mapped_regions.push_back({address, end_address});
+
+    address = end_address;
+  }
+  ScanRootRegions(frontier, mapped_regions);
+}
+
+// On darwin, we can intercept _exit gracefully, and return a failing exit code
+// if required at that point. Calling Die() here is undefined behavior and
+// causes rare race conditions.
+void HandleLeaks() {}
+
+void LockStuffAndStopTheWorld(StopTheWorldCallback callback,
+                              CheckForLeaksParam *argument) {
+  ScopedStopTheWorldLock lock;
+  StopTheWorld(callback, argument);
+}
+
+}  // namespace __lsan
+
+#endif // CAN_SANITIZE_LEAKS && SANITIZER_APPLE