Simplified the code for "private broadcasts" used to initialize constants of primitive type.  This code is unchanged for GASNET_EVERYTHING in which we simply do a _chpl_comm_put to every locale other than the one that executes the call.  For GASNET_LARGE and GASNET_FAST, we used to place the data on the heap and then use _chpl_comm_fork to create a remote task that then did a _chpl_comm_get back to get the data off the heap.  Now we create an active message that passes the data to every locale.  The active message does not need to access any remote data.  This improves communication efficiency as well as overall efficiency because the _chpl_comm_fork creates a separate thread, etc., which we no longer do.
Simplified the code for "private broadcasts" used to initialize
constants of primitive type.  This code is unchanged for
GASNET_EVERYTHING in which we simply do a _chpl_comm_put to every
locale other than the one that executes the call.  For GASNET_LARGE
and GASNET_FAST, we used to place the data on the heap and then use
_chpl_comm_fork to create a remote task that then did a _chpl_comm_get
back to get the data off the heap.  Now we create an active message
that passes the data to every locale.  The active message does not
need to access any remote data.  This improves communication
efficiency as well as overall efficiency because the _chpl_comm_fork
creates a separate thread, etc., which we no longer do.

This checkin is part of my effort to address the non-deterministic seg
faults seen in multi-locale runs of any program.  This decreases the
frequency of such seg faults in simple programs.  For example, I ran
the program trivial/deitz/test_var_decl1 20,000 times to see 8 seg
faults drop down to 0 seg faults.  I ran this same program 200,000
times to see 87 seg faults drop down to 1 seg fault, 3 amudp warnings,
and 1 recursive failure in AMUDP_SPMDShutdown.


git-svn-id: 88467cb1fb04b8a755be7e1ee1026be4190196ef@15149 3a8e244f-b0f2-452b-bcba-4c88e055c3ca

hildeth/chapel,chizarlicious/chapel,CoryMcCartan/chapel,chizarlicious/chapel,sungeunchoi/chapel,chizarlicious/chapel,CoryMcCartan/chapel,sungeunchoi/chapel,CoryMcCartan/chapel,chizarlicious/chapel,CoryMcCartan/chapel,hildeth/chapel,sungeunchoi/chapel,hildeth/chapel,CoryMcCartan/chapel,chizarlicious/chapel,hildeth/chapel,sungeunchoi/chapel,hildeth/chapel,CoryMcCartan/chapel,sungeunchoi/chapel,chizarlicious/chapel,hildeth/chapel,sungeunchoi/chapel,sungeunchoi/chapel,CoryMcCartan/chapel,sungeunchoi/chapel,hildeth/chapel,chizarlicious/chapel