FPEControlSvc Class Reference

Service to enable or disable floating-point exceptions. More...

#include <FPEControlSvc.h>

Inheritance diagram for FPEControlSvc:

Collaboration diagram for FPEControlSvc:

Public Member Functions
virtual StatusCode	initialize ()
	Standard initialize method.
virtual StatusCode	finalize ()
	Standard finalize method.
virtual void	onCreate (const IAlgTool *)
	Called after each tool has been created.
	FPEControlSvc (const std::string &name, ISvcLocator *svcloc)
	Constructor.
MsgStream &	msg () const
bool	msgLvl (const MSG::Level lvl) const

Private Member Functions
void	setFPU ()
	Set the FPU exception masks from m_enabled and m_disabled.
void	prophand (Gaudi::Details::PropertyBase &prop)
	Property change handler.

Private Attributes
StringArrayProperty	m_exceptions
	Property specifying the desired exception mask.
ServiceHandle< IToolSvc >	m_toolSvc
	Tool service.
fenv_t	m_env
	The FP environment before we initialize.
bool	m_haveEnv
	Flag that we've retrieved the environment.
int	m_enabled
	Mask of enabled exceptions.
int	m_disabled
	Mask of disabled exceptions.
bool	m_removeInFinalize
	boolean to decide to (not) remove the observer in finalize
std::string	m_feSetRounding
	flag to decide on rounding mode (for stability tests)

Detailed Description

Service to enable or disable floating-point exceptions.

When this service initializes, it will set the floating-point exception mask based on the value of the Exceptions property. This is a string array, containing any of the following strings to enable the corresponding exceptions:

inexact divbyzero underflow overflow invalid

In addition, these words can appear with a ! in front to disable them. Later words take precendence over earlier ones.

The default is divbyzero overflow invalid.

The property can be reassigned at any time to change the current exception mask.

Definition at line 50 of file FPEControlSvc.h.

Constructor & Destructor Documentation

FPEControlSvc()

FPEControlSvc::FPEControlSvc	(	const std::string &	name,
		ISvcLocator *	svc )

Constructor.

Parameters

name	The service name.
svcloc	The service locator.

Definition at line 22 of file FPEControlSvc.cxx.

  : AthService( name, svc ),
    m_toolSvc ("ToolSvc", name),
    m_env(),
    m_haveEnv(false),
    m_enabled (0),
    m_disabled (0),
    m_removeInFinalize(false),
    m_feSetRounding("")
{
  declareProperty("Exceptions", m_exceptions);
  declareProperty("ToolSvc",    m_toolSvc);
  declareProperty("FERoundingMode", m_feSetRounding);
  m_exceptions.declareUpdateHandler (&FPEControlSvc::prophand, this);
 
  // Set up the default exceptions.
  std::vector<std::string> defexc;
  defexc.push_back ("invalid");
  defexc.push_back ("divbyzero");
  defexc.push_back ("overflow");
  m_exceptions = defexc;
}

Member Function Documentation

finalize()

StatusCode FPEControlSvc::finalize ( )

virtual

Standard finalize method.

Definition at line 92 of file FPEControlSvc.cxx.

{
  // remove only if requested
  if (m_removeInFinalize)
    {
      // Restore the FP environment to what is was before we ran.
      fesetenv (&m_env);
    }
  
  return StatusCode::SUCCESS;
}

initialize()

StatusCode FPEControlSvc::initialize ( )

virtual

Standard initialize method.

Definition at line 49 of file FPEControlSvc.cxx.

{
  // And change the exception mask.
  prophand (m_exceptions);
 
  // Add ourself as an observer.
  CHECK( m_toolSvc.retrieve() );
  m_toolSvc->registerObserver (this);
  
  if(m_feSetRounding!="")
    {
      REPORT_MESSAGE (MSG::INFO) << "FE Rounding mode " << m_feSetRounding << " requested";
      if(m_feSetRounding=="FE_TONEAREST")
    {
      if ( fesetround(FE_TONEAREST) )
          REPORT_MESSAGE (MSG::WARNING) << "Couldn't change FE Rounding to mode FE_TONEAREST !";
    }
      else if(m_feSetRounding=="FE_UPWARD")
    {
      if ( fesetround(FE_UPWARD) )
        REPORT_MESSAGE (MSG::WARNING) << "Couldn't change FE Rounding to mode FE_UPWARD !";
    }
      else if(m_feSetRounding=="FE_DOWNWARD")
    {
      if ( fesetround(FE_DOWNWARD) )
        REPORT_MESSAGE (MSG::WARNING) << "Couldn't change FE Rounding to mode FE_DOWNWARD !";
    }
      else if(m_feSetRounding=="FE_TOWARDZERO")
    {
      if ( fesetround(FE_TOWARDZERO) )
        REPORT_MESSAGE (MSG::WARNING) << "Couldn't change FE Rounding to mode FE_TOWARDZERO !";
    }
      else
    REPORT_MESSAGE (MSG::WARNING) << "Don't know FE Rounding to mode " << m_feSetRounding;
    }
  
  return StatusCode::SUCCESS;
}

msg()

MsgStream & AthCommonMsg< Service >::msg ( ) const

inlineinherited

Definition at line 24 of file AthCommonMsg.h.

                                {
    return this->msgStream();
  }

msgLvl()

bool AthCommonMsg< Service >::msgLvl ( const MSG::Level lvl ) const

inlineinherited

Definition at line 30 of file AthCommonMsg.h.

                                               {
    return this->msgLevel(lvl);
  }

onCreate()

void FPEControlSvc::onCreate ( const IAlgTool * )

virtual

Called after each tool has been created.

Observer callback.

This is called after each tool is created. We make sure that the FPE mask is still set correctly. We do this because some tools have been observed to mask off exceptions. In particular, libgfortran will mask exceptions off when it's first loaded. So, if libgfortran hasn't yet been loaded when we initialize, but then gets loaded later, then exceptions will remain masked off.

Definition at line 115 of file FPEControlSvc.cxx.

{
  setFPU();
}

prophand()

void FPEControlSvc::prophand ( Gaudi::Details::PropertyBase & prop )

private

Property change handler.

Definition at line 153 of file FPEControlSvc.cxx.

{
  if (!m_haveEnv) {
    // Save the current FP environment.
    fegetenv (&m_env);
    m_haveEnv = true;
  }
  else {
    // Reset to the FP environment before we started.
    fesetenv (&m_env);
  }
 
  // Figure out which exceptions to enable/disable.
  m_enabled = 0;
  m_disabled = 0;
  const std::vector<std::string>& v = m_exceptions.value();
  for (size_t i = 0; i < v.size(); i++) {
    bool onoff = true;
    const char* s = v[i].c_str();
    if (!s) continue;
    if (s[0] == '!') {
      onoff = false;
      ++s;
    }
    int thisexc = 0;
    if (strcasecmp (s, "inexact") == 0)
      thisexc = FE_INEXACT;
    else if (strcasecmp (s, "divbyzero") == 0)
      thisexc = FE_DIVBYZERO;
    else if (strcasecmp (s, "underflow") == 0)
      thisexc = FE_UNDERFLOW;
    else if (strcasecmp (s, "overflow") == 0)
      thisexc = FE_OVERFLOW;
    else if (strcasecmp (s, "invalid") == 0)
      thisexc = FE_INVALID;
    else {
      REPORT_MESSAGE (MSG::INFO)
        << "Unknown exception name: " << v[i];
      continue;
    }
 
    if (onoff) {
      m_enabled |= thisexc;
      m_disabled &= ~thisexc;
    }
    else {
      m_disabled |= thisexc;
      m_enabled &= ~thisexc;
    }
  }
 
  // Say what we're doing, and change the masks.
  REPORT_MESSAGE (MSG::INFO)
    << "Enable: " << mask_to_string (m_enabled)
    << "Disable: " << mask_to_string (m_disabled);
 
  setFPU();
}

setFPU()

void FPEControlSvc::setFPU ( )

private

Set the FPU exception masks from m_enabled and m_disabled.

Definition at line 216 of file FPEControlSvc.cxx.

{
  feclearexcept (m_enabled);
#ifdef __GLIBC__
  feenableexcept (m_enabled);
  fedisableexcept (m_disabled);
#elif defined __APPLE__
#include "CxxUtils/excepts.h"
  feenableexcept (m_enabled);
  fedisableexcept (m_disabled);
#else
  // The functions above are gnu-specific.
  // Without GNU, we do it the harder way.
  fenv_t newval;
  fegetenv(&newval);
 
  // CSR bit on means that the exception is masked.
 
  newval.__control_word &= ~m_enabled;
  newval.__control_word |=  m_disabled;
# ifdef __x86_64
  // SSE floating point uses separate exception masks.
  newval.__mxcsr &= (~m_enabled) << 7;
  newval.__mxcsr |= ( m_disabled) << 7;
# endif
  fesetenv(&newval);
#endif
}

Member Data Documentation

m_disabled

int FPEControlSvc::m_disabled

private

Mask of disabled exceptions.

Definition at line 92 of file FPEControlSvc.h.

m_enabled

int FPEControlSvc::m_enabled

private

Mask of enabled exceptions.

Definition at line 89 of file FPEControlSvc.h.

m_env

fenv_t FPEControlSvc::m_env

private

The FP environment before we initialize.

Definition at line 83 of file FPEControlSvc.h.

m_exceptions

StringArrayProperty FPEControlSvc::m_exceptions

private

Property specifying the desired exception mask.

Definition at line 77 of file FPEControlSvc.h.

m_feSetRounding

std::string FPEControlSvc::m_feSetRounding

private

flag to decide on rounding mode (for stability tests)

Definition at line 98 of file FPEControlSvc.h.

m_haveEnv

bool FPEControlSvc::m_haveEnv

private

Flag that we've retrieved the environment.

Definition at line 86 of file FPEControlSvc.h.

m_removeInFinalize

bool FPEControlSvc::m_removeInFinalize

private

boolean to decide to (not) remove the observer in finalize

Definition at line 95 of file FPEControlSvc.h.

m_toolSvc

ServiceHandle<IToolSvc> FPEControlSvc::m_toolSvc

private

Tool service.

Definition at line 80 of file FPEControlSvc.h.

---

The documentation for this class was generated from the following files:

• FPEControlSvc.h
• FPEControlSvc.cxx