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//===-- esan_sideline.h -----------------------------------------*- C++ -*-===//
// The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// This file is a part of EfficiencySanitizer, a family of performance tuners.
// Esan sideline thread support.
#include "sanitizer_common/sanitizer_atomic.h"
#include "sanitizer_common/sanitizer_internal_defs.h"
#include "sanitizer_common/sanitizer_platform_limits_posix.h"
namespace __esan {
typedef void (*SidelineFunc)(void *Arg);
// Currently only one sideline thread is supported.
// It calls the SidelineFunc passed to launchThread once on each sample at the
// given frequency in real time (i.e., wall clock time).
class SidelineThread {
// We cannot initialize any fields in the constructor as it will be called
// *after* launchThread for a static instance, as esan.module_ctor is called
// before static initializers.
SidelineThread() {}
~SidelineThread() {}
// To simplify declaration in sanitizer code where we want to avoid
// heap allocations, the constructor and destructor do nothing and
// launchThread and joinThread do the real work.
// They should each be called just once.
bool launchThread(SidelineFunc takeSample, void *Arg, u32 FreqMilliSec);
bool joinThread();
// Must be called from the sideline thread itself.
bool adjustTimer(u32 FreqMilliSec);
static int runSideline(void *Arg);
static void registerSignal(int SigNum);
static void handleSidelineSignal(int SigNum, __sanitizer_siginfo *SigInfo,
void *Ctx);
char *Stack;
SidelineFunc sampleFunc;
void *FuncArg;
u32 Freq;
uptr SidelineId;
atomic_uintptr_t SidelineExit;
} // namespace __esan