llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_libignore.h

116 lines
3.5 KiB
C++

//===-- sanitizer_libignore.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
//
//===----------------------------------------------------------------------===//
//
// LibIgnore allows to ignore all interceptors called from a particular set
// of dynamic libraries. LibIgnore can be initialized with several templates
// of names of libraries to be ignored. It finds code ranges for the libraries;
// and checks whether the provided PC value belongs to the code ranges.
//
//===----------------------------------------------------------------------===//
#ifndef SANITIZER_LIBIGNORE_H
#define SANITIZER_LIBIGNORE_H
#include "sanitizer_internal_defs.h"
#include "sanitizer_common.h"
#include "sanitizer_atomic.h"
#include "sanitizer_mutex.h"
namespace __sanitizer {
class LibIgnore {
public:
explicit LibIgnore(LinkerInitialized);
// Must be called during initialization.
void AddIgnoredLibrary(const char *name_templ);
void IgnoreNoninstrumentedModules(bool enable) {
track_instrumented_libs_ = enable;
}
// Must be called after a new dynamic library is loaded.
void OnLibraryLoaded(const char *name);
// Must be called after a dynamic library is unloaded.
void OnLibraryUnloaded();
// Checks whether the provided PC belongs to one of the ignored libraries or
// the PC should be ignored because it belongs to an non-instrumented module
// (when ignore_noninstrumented_modules=1). Also returns true via
// "pc_in_ignored_lib" if the PC is in an ignored library, false otherwise.
bool IsIgnored(uptr pc, bool *pc_in_ignored_lib) const;
// Checks whether the provided PC belongs to an instrumented module.
bool IsPcInstrumented(uptr pc) const;
private:
struct Lib {
char *templ;
char *name;
char *real_name; // target of symlink
bool loaded;
};
struct LibCodeRange {
uptr begin;
uptr end;
};
inline bool IsInRange(uptr pc, const LibCodeRange &range) const {
return (pc >= range.begin && pc < range.end);
}
static const uptr kMaxIgnoredRanges = 128;
static const uptr kMaxInstrumentedRanges = 1024;
static const uptr kMaxLibs = 1024;
// Hot part:
atomic_uintptr_t ignored_ranges_count_;
LibCodeRange ignored_code_ranges_[kMaxIgnoredRanges];
atomic_uintptr_t instrumented_ranges_count_;
LibCodeRange instrumented_code_ranges_[kMaxInstrumentedRanges];
// Cold part:
BlockingMutex mutex_;
uptr count_;
Lib libs_[kMaxLibs];
bool track_instrumented_libs_;
// Disallow copying of LibIgnore objects.
LibIgnore(const LibIgnore&); // not implemented
void operator = (const LibIgnore&); // not implemented
};
inline bool LibIgnore::IsIgnored(uptr pc, bool *pc_in_ignored_lib) const {
const uptr n = atomic_load(&ignored_ranges_count_, memory_order_acquire);
for (uptr i = 0; i < n; i++) {
if (IsInRange(pc, ignored_code_ranges_[i])) {
*pc_in_ignored_lib = true;
return true;
}
}
*pc_in_ignored_lib = false;
if (track_instrumented_libs_ && !IsPcInstrumented(pc))
return true;
return false;
}
inline bool LibIgnore::IsPcInstrumented(uptr pc) const {
const uptr n = atomic_load(&instrumented_ranges_count_, memory_order_acquire);
for (uptr i = 0; i < n; i++) {
if (IsInRange(pc, instrumented_code_ranges_[i]))
return true;
}
return false;
}
} // namespace __sanitizer
#endif // SANITIZER_LIBIGNORE_H