Files
clang-p2996/lldb/source/Plugins/Process/Linux/SingleStepCheck.h
Pavel Labath 8abd34f015 NPL: Compartmentalize arm64 single step workaround better
The main motivation for me doing this is being able to build an arm
android lldb-server against api level 9 headers, but it seems like a
good cleanup nonetheless.

The entirety of the cpu_set_t dance now resides in SingleStepCheck.cpp,
which is only built on arm64.

llvm-svn: 293046
2017-01-25 11:19:45 +00:00

55 lines
1.6 KiB
C++

//===-- SingleStepCheck.h ------------------------------------- -*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef liblldb_SingleStepCheck_H_
#define liblldb_SingleStepCheck_H_
#include "sched.h"
#include "llvm/ADT/Optional.h"
#include <sys/types.h>
namespace lldb_private {
namespace process_linux {
// arm64 linux had a bug which prevented single-stepping and watchpoints from
// working on non-boot cpus, due to them being incorrectly initialized after
// coming out of suspend. This issue is particularly affecting android M, which
// uses suspend ("doze mode") quite aggressively. This code detects that
// situation and makes single-stepping work by doing all the step operations on
// the boot cpu.
//
// The underlying issue has been fixed in android N and linux 4.4. This code can
// be removed once these systems become obsolete.
#if defined(__arm64__) || defined(__aarch64__)
class SingleStepWorkaround {
::pid_t m_tid;
cpu_set_t m_original_set;
public:
SingleStepWorkaround(::pid_t tid, cpu_set_t original_set)
: m_tid(tid), m_original_set(original_set) {}
~SingleStepWorkaround();
static llvm::Optional<SingleStepWorkaround> Get(::pid_t tid);
};
#else
class SingleStepWorkaround {
public:
static llvm::Optional<SingleStepWorkaround> Get(::pid_t tid) {
return llvm::None;
}
};
#endif
} // end namespace process_linux
} // end namespace lldb_private
#endif // #ifndef liblldb_SingleStepCheck_H_