debug.cc

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#include "base/debug.hh"
 
#include <sys/types.h>
#include <unistd.h>
 
#include <algorithm>
#include <csignal>
 
#include "base/cprintf.hh"
#include "base/logging.hh"
 
namespace gem5
{
 
GEM5_DEPRECATED_NAMESPACE(Debug, debug);
namespace debug
{
 
//
// This function will cause the process to signal itself with a
// SIGTRAP which is ignored if not in gdb, but will cause the debugger
// to break if in gdb.
//
void
breakpoint()
{
#ifndef NDEBUG
    kill(getpid(), SIGTRAP);
#else
    cprintf("debug::breakpoint suppressed, compiled with NDEBUG\n");
#endif
}
 
// Used to check the freshness of cached views of all flags.
FlagsMap &
allFlags()
{
    // Ensure that the special "All" compound debug flag has been created,
    // and avoid infinite recursion.
    static bool done = false;
    if (!done) {
        done = true;
        AllFlagsFlag::instance();
    }
    static FlagsMap flags;
    return flags;
}
 
bool Flag::_globalEnable = false;
 
Flag *
findFlag(const std::string &name)
{
    FlagsMap::iterator i = allFlags().find(name);
    if (i == allFlags().end()) {
        return NULL;
    }
    return i->second;
}
 
Flag::Flag(const char *name, const char *desc)
    : _name(name), _desc(desc)
{
    std::pair<FlagsMap::iterator, bool> result =
        allFlags().insert(std::make_pair(name, this));
 
    panic_if(!result.second, "Flag %s already defined!", name);
 
    sync();
}
 
Flag::~Flag()
{
    allFlags().erase(name());
}
 
void
Flag::globalEnable()
{
    _globalEnable = true;
    for (auto& i : allFlags())
        i.second->sync();
}
 
void
Flag::globalDisable()
{
    _globalEnable = false;
    for (auto& i : allFlags())
        i.second->sync();
}
 
SimpleFlag::SimpleFlag(const char *name, const char *desc, bool is_format)
  : Flag(name, desc), _isFormat(is_format)
{
    // Add non-format flags to the special "All" compound flag.
    if (!isFormat())
        AllFlagsFlag::instance().add(this);
}
 
void
CompoundFlag::enable()
{
    for (auto& k : _kids)
        k->enable();
}
 
void
CompoundFlag::disable()
{
    for (auto& k : _kids)
        k->disable();
}
 
AllFlagsFlag::AllFlagsFlag() : CompoundFlag("All",
        "Controls all debug flags. It should not be used within C++ code.", {})
{}
 
void
AllFlagsFlag::add(SimpleFlag *flag)
{
    ++_version;
    _kids.push_back(flag);
}
 
int AllFlagsFlag::_version = 0;
 
AllFlagsFlag &
AllFlagsFlag::instance()
{
    static AllFlagsFlag flag;
    return flag;
}
 
bool
changeFlag(const char *s, bool value)
{
    Flag *f = findFlag(s);
    if (!f)
        return false;
 
    if (value)
        f->enable();
    else
        f->disable();
 
    return true;
}
 
} // namespace debug
 
// add a set of functions that can easily be invoked from gdb
void
setDebugFlag(const char *string)
{
    debug::changeFlag(string, true);
}
 
void
clearDebugFlag(const char *string)
{
    debug::changeFlag(string, false);
}
 
void
dumpDebugFlags(std::ostream &os)
{
    using namespace debug;
    FlagsMap::iterator i = allFlags().begin();
    FlagsMap::iterator end = allFlags().end();
    for (; i != end; ++i) {
        SimpleFlag *f = dynamic_cast<SimpleFlag *>(i->second);
        if (f && f->tracing())
            ccprintf(os, "%s\n", f->name());
    }
}
 
} // namespace gem5