[feat] Add support for TACC's ibrun parallel job launcher

docs/configure.rst

@@ -305,6 +305,8 @@ ReFrame supports the following parallel job launchers:
 * ``alps``: Programs on the configured partition will be launched using the ``aprun`` command.
 * ``mpirun``: Programs on the configured partition will be launched using the ``mpirun`` command.
 * ``mpiexec``: Programs on the configured partition will be launched using the ``mpiexec`` command.
+* ``ibrun``: *[new in 2.21]* Programs on the configured partition will be launched using the ``ibrun`` command.
+  This is a custom parallel job launcher used at `TACC <https://portal.tacc.utexas.edu/user-guides/stampede2>`__.
 * ``local``: Programs on the configured partition will be launched as-is without using any parallel program launcher.
 * ``ssh``: *[new in 2.20]* Programs on the configured partition will be launched using SSH.
   This option uses the partition's ``access`` parameter (see `above <#partition-configuration>`__) in order to determine the remote host and any additional options to be passed to the SSH client.

reframe/core/launchers/mpi.py

@@ -8,6 +8,14 @@ def command(self, job):
         return ['srun']
 
 
+@register_launcher('ibrun')
+class IbrunLauncher(JobLauncher):
+    '''TACC's custom parallel job launcher.'''
+
+    def command(self, job):
+        return ['ibrun']
+
+
 @register_launcher('alps')
 class AlpsLauncher(JobLauncher):
     def command(self, job):