Our website uses cookies to enhance your browsing experience.
Accept
to the top
close form

Fill out the form in 2 simple steps below:

Your contact information:

Step 1
Congratulations! This is your promo code!

Desired license type:

Step 2
Team license
Enterprise license
** By clicking this button you agree to our Privacy Policy statement
close form
Request our prices
New License
License Renewal
--Select currency--
USD
EUR
* By clicking this button you agree to our Privacy Policy statement

close form
Free PVS‑Studio license for Microsoft MVP specialists
* By clicking this button you agree to our Privacy Policy statement

close form
To get the licence for your open-source project, please fill out this form
* By clicking this button you agree to our Privacy Policy statement

close form
I am interested to try it on the platforms:
* By clicking this button you agree to our Privacy Policy statement

close form
check circle
Message submitted.

Your message has been sent. We will email you at


If you haven't received our response, please do the following:
check your Spam/Junk folder and click the "Not Spam" button for our message.
This way, you won't miss messages from our team in the future.

>
>
Processing of exceptions inside paralle…

Processing of exceptions inside parallel sections

Sep 07 2009
Author:

Some time ago I wrote in the blog about some problems (see note "OpenMP and exceptions") occurring when an exception excesses the boundaries of parallel sections. I have also told you that an exception can be generated by new operator and that is must be caught and processed before it leaves the parallel section. The constructions used for this are rather inconvenient and complicated. Not so long ago I was told that in this case the smartest solution is using new operator which does not generate exceptions. That is using of a "nothrow"-variant of new operator which returns NULL in case of failure and allows you to write a simpler OpenMP code.

To get acquainted with new operator which does not generate exceptions see the article "Nothrow new". And here I will give only two examples which demonstrate the idea of the solution very clear.

The code with processing of an exception:

size_t errCount = 0;
#pragma omp parallel for num_threads(4) reduction(+: errCount)
for(int i = 0; i < 4; i++)
{
  try {
    float *ptr = new float[10000];
    // code
    delete [] ptr;
  }
  catch (std::bad_alloc &)
  {
    ++errCount;
  }
}

Simplified code without processing of exceptions:

size_t errCount = 0;
#pragma omp parallel for num_threads(4) reduction(+: errCount)
for(int i = 0; i < 4; i++)
{
  float *ptr = new(std::nothrow) float[10000];
  if (ptr == NULL) {
    ++errCount;
  } else {
    // code
    delete [] ptr;
  }
}
Popular related articles


Comments (0)

Next comments next comments
close comment form