Build fewer LLVM components to speed compile

This patch significantly reduces the build
size and the build time. It omits some LLVM
and Clang components we don't use and only
builds host and x86 and x86-64 backends.

Used to take 23 minutes, now takes 18 minutes
to CHPL_LLVM=llvm time make on my machine. In
addition, llvm/build is now 8G (was 12G)
and llvm/install is now 4.6G (was 5.8G).
Classify this future as a "bug".
Merge pull request #308 from sungeunchoi/test

Classify this future as a "bug".  The tag was missing prior to this commit.
Lower stack size for test/stress/deitz/test_10k_coforall.chpl

This test has the potential to create a lot tasks that exist simultaneously. On
some of our tests boxes with limited ram, we run out of memory. Qthreads places
no limit on the number of qthreads and thus stacks that can exist at once. For
tests like this I've been trying to limit the "max" memory usage to under 4GB.
4GB seems like a large enough value for correctness tests, and it is low enough
that our 32 bit machines shouldn't have trouble.
Merge pull request #309 from ronawho/qthreads-timeouts

Lower stack size for test/stress/deitz/test_10k_coforall.chpl

[trivial, not reviewed]

This test has the potential to create a lot tasks that exist simultaneously. On
some of our tests boxes with limited ram, we run out of memory. Qthreads places
no limit on the number of qthreads and thus stacks that can exist at once. For
tests like this I've been trying to limit the "max" memory usage to under 4GB.
4GB seems like a large enough value for correctness tests, and it is low enough
that our 32 bit machines shouldn't have trouble.
Lower the problem size for test_many_domain and test_many_array

Since switching to qthreads these tests take a lot longer to execute and
test_many_domain times out pretty often. test_many_domain has also been timing
out for numa+gasnet for months

This doesn't reflect a real problem with qthreads, so much as it does a
"problem" with the testing framework. Even with qthreads configured with
oversubscription and affinity off there is still interference from multiple
qthreads instances running on the same machine.

I tested these two programs out on an xc and on a cluster, and the qthreads
version was a few seconds quicker so I'm pretty confident in my claim that it's
just how we test gasnet+qthreads that's responsible for the slow down and not
some performance mystery that needs to be explored.

These new sizes lower the execution time to ~30 seconds.
Merge pull request #311 from ronawho/qthreads-timeouts

Lower the problem size for test_many_domain and test_many_array

[trivial, not reviewed]

Since switching to qthreads these tests take a lot longer to execute and
test_many_domain times out pretty often. test_many_domain has also been timing
out for numa+gasnet for months

This doesn't reflect a real problem with qthreads, so much as it does a
"problem" with the testing framework. Even with qthreads configured with
oversubscription and affinity off there is still interference from multiple
qthreads instances running on the same machine.

I tested these two programs out on an xc and on a cluster, and the qthreads
version was a few seconds quicker so I'm pretty confident in my claim that it's
just how we test gasnet+qthreads that's responsible for the slow down and not
some performance mystery that needs to be explored.

These new sizes lower the execution time to ~30 seconds.
Merge pull request #292 from mppf/llvm-faster-build

Build fewer LLVM components to speed compile

This patch significantly reduces the build
size and the build time. It omits some LLVM
and Clang components we don't use and only
builds host and x86 and x86-64 backends.

Used to take 23 minutes, now takes 18 minutes
to CHPL_LLVM=llvm time make on my machine. In
addition, llvm/build is now 8G (was 12G)
and llvm/install is now 4.6G (was 5.8G).