1 files changed, 218 insertions, 0 deletions
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_coverage_libcdep_new.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_coverage_libcdep_new.cpp
new file mode 100644
index 000000000000..6a75792f9262
--- /dev/null
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_coverage_libcdep_new.cpp
@@ -0,0 +1,218 @@
+//===-- sanitizer_coverage_libcdep_new.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
+//
+//===----------------------------------------------------------------------===//
+// Sanitizer Coverage Controller for Trace PC Guard.
+
+#include "sanitizer_platform.h"
+
+#if !SANITIZER_FUCHSIA
+#include "sancov_flags.h"
+#include "sanitizer_allocator_internal.h"
+#include "sanitizer_atomic.h"
+#include "sanitizer_common.h"
+#include "sanitizer_file.h"
+
+using namespace __sanitizer;
+
+using AddressRange = LoadedModule::AddressRange;
+
+namespace __sancov {
+namespace {
+
+static const u64 Magic64 = 0xC0BFFFFFFFFFFF64ULL;
+static const u64 Magic32 = 0xC0BFFFFFFFFFFF32ULL;
+static const u64 Magic = SANITIZER_WORDSIZE == 64 ? Magic64 : Magic32;
+
+static fd_t OpenFile(const char* path) {
+  error_t err;
+  fd_t fd = OpenFile(path, WrOnly, &err);
+  if (fd == kInvalidFd)
+    Report("SanitizerCoverage: failed to open %s for writing (reason: %d)\n",
+           path, err);
+  return fd;
+}
+
+static void GetCoverageFilename(char* path, const char* name,
+                                const char* extension) {
+  CHECK(name);
+  internal_snprintf(path, kMaxPathLength, "%s/%s.%zd.%s",
+                    common_flags()->coverage_dir, name, internal_getpid(),
+                    extension);
+}
+
+static void WriteModuleCoverage(char* file_path, const char* module_name,
+                                const uptr* pcs, uptr len) {
+  GetCoverageFilename(file_path, StripModuleName(module_name), "sancov");
+  fd_t fd = OpenFile(file_path);
+  WriteToFile(fd, &Magic, sizeof(Magic));
+  WriteToFile(fd, pcs, len * sizeof(*pcs));
+  CloseFile(fd);
+  Printf("SanitizerCoverage: %s: %zd PCs written\n", file_path, len);
+}
+
+static void SanitizerDumpCoverage(const uptr* unsorted_pcs, uptr len) {
+  if (!len) return;
+
+  char* file_path = static_cast<char*>(InternalAlloc(kMaxPathLength));
+  char* module_name = static_cast<char*>(InternalAlloc(kMaxPathLength));
+  uptr* pcs = static_cast<uptr*>(InternalAlloc(len * sizeof(uptr)));
+
+  internal_memcpy(pcs, unsorted_pcs, len * sizeof(uptr));
+  Sort(pcs, len);
+
+  bool module_found = false;
+  uptr last_base = 0;
+  uptr module_start_idx = 0;
+
+  for (uptr i = 0; i < len; ++i) {
+    const uptr pc = pcs[i];
+    if (!pc) continue;
+
+    if (!__sanitizer_get_module_and_offset_for_pc(pc, nullptr, 0, &pcs[i])) {
+      Printf("ERROR: unknown pc 0x%x (may happen if dlclose is used)\n", pc);
+      continue;
+    }
+    uptr module_base = pc - pcs[i];
+
+    if (module_base != last_base || !module_found) {
+      if (module_found) {
+        WriteModuleCoverage(file_path, module_name, &pcs[module_start_idx],
+                            i - module_start_idx);
+      }
+
+      last_base = module_base;
+      module_start_idx = i;
+      module_found = true;
+      __sanitizer_get_module_and_offset_for_pc(pc, module_name, kMaxPathLength,
+                                               &pcs[i]);
+    }
+  }
+
+  if (module_found) {
+    WriteModuleCoverage(file_path, module_name, &pcs[module_start_idx],
+                        len - module_start_idx);
+  }
+
+  InternalFree(file_path);
+  InternalFree(module_name);
+  InternalFree(pcs);
+}
+
+// Collects trace-pc guard coverage.
+// This class relies on zero-initialization.
+class TracePcGuardController {
+ public:
+  void Initialize() {
+    CHECK(!initialized);
+
+    initialized = true;
+    InitializeSancovFlags();
+
+    pc_vector.Initialize(0);
+  }
+
+  void InitTracePcGuard(u32* start, u32* end) {
+    if (!initialized) Initialize();
+    CHECK(!*start);
+    CHECK_NE(start, end);
+
+    u32 i = pc_vector.size();
+    for (u32* p = start; p < end; p++) *p = ++i;
+    pc_vector.resize(i);
+  }
+
+  void TracePcGuard(u32* guard, uptr pc) {
+    u32 idx = *guard;
+    if (!idx) return;
+    // we start indices from 1.
+    atomic_uintptr_t* pc_ptr =
+        reinterpret_cast<atomic_uintptr_t*>(&pc_vector[idx - 1]);
+    if (atomic_load(pc_ptr, memory_order_relaxed) == 0)
+      atomic_store(pc_ptr, pc, memory_order_relaxed);
+  }
+
+  void Reset() {
+    internal_memset(&pc_vector[0], 0, sizeof(pc_vector[0]) * pc_vector.size());
+  }
+
+  void Dump() {
+    if (!initialized || !common_flags()->coverage) return;
+    __sanitizer_dump_coverage(pc_vector.data(), pc_vector.size());
+  }
+
+ private:
+  bool initialized;
+  InternalMmapVectorNoCtor<uptr> pc_vector;
+};
+
+static TracePcGuardController pc_guard_controller;
+
+}  // namespace
+}  // namespace __sancov
+
+namespace __sanitizer {
+void InitializeCoverage(bool enabled, const char *dir) {
+  static bool coverage_enabled = false;
+  if (coverage_enabled)
+    return;  // May happen if two sanitizer enable coverage in the same process.
+  coverage_enabled = enabled;
+  Atexit(__sanitizer_cov_dump);
+  AddDieCallback(__sanitizer_cov_dump);
+}
+} // namespace __sanitizer
+
+extern "C" {
+SANITIZER_INTERFACE_ATTRIBUTE void __sanitizer_dump_coverage(const uptr* pcs,
+                                                             uptr len) {
+  return __sancov::SanitizerDumpCoverage(pcs, len);
+}
+
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_pc_guard, u32* guard) {
+  if (!*guard) return;
+  __sancov::pc_guard_controller.TracePcGuard(guard, GET_CALLER_PC() - 1);
+}
+
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_pc_guard_init,
+                             u32* start, u32* end) {
+  if (start == end || *start) return;
+  __sancov::pc_guard_controller.InitTracePcGuard(start, end);
+}
+
+SANITIZER_INTERFACE_ATTRIBUTE void __sanitizer_dump_trace_pc_guard_coverage() {
+  __sancov::pc_guard_controller.Dump();
+}
+SANITIZER_INTERFACE_ATTRIBUTE void __sanitizer_cov_dump() {
+  __sanitizer_dump_trace_pc_guard_coverage();
+}
+SANITIZER_INTERFACE_ATTRIBUTE void __sanitizer_cov_reset() {
+  __sancov::pc_guard_controller.Reset();
+}
+// Default empty implementations (weak). Users should redefine them.
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_cmp, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_cmp1, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_cmp2, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_cmp4, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_cmp8, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_const_cmp1, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_const_cmp2, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_const_cmp4, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_const_cmp8, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_switch, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_div4, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_div8, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_gep, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_trace_pc_indir, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_8bit_counters_init, void) {}
+SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_cov_pcs_init, void) {}
+}  // extern "C"
+// Weak definition for code instrumented with -fsanitize-coverage=stack-depth
+// and later linked with code containing a strong definition.
+// E.g., -fsanitize=fuzzer-no-link
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+SANITIZER_TLS_INITIAL_EXEC_ATTRIBUTE uptr __sancov_lowest_stack;
+
+#endif  // !SANITIZER_FUCHSIA