[inductor] do comm compute overlap at aten fx level (#163215)

This is first part of the stack that does comm/compute reordering, and then uses the exposure analysis to do bucketing.

Subsequent prs will handle:
- use of exposure analysis to do bucketing
- make sure inductor respects comm/compute overlapping done at fx level
- non-profiling mm estimation/rank broadcasting of profile results

Other mis:
- Validate accuracy of nccl estimations  ( use ruisi's profiling instead ?)

For a llama 2d parallelism test, on forward, we overlap all but 2 of potentially hidden collectives. For backward, we overlap 217/269 of potentially hidden collectives. If you increase `compute_overlap_multipler` (for fudge factor of inaccurate comms estimation), that goes down to all but 16 of potentially hidden collectives.

fwd example: https://gist.github.com/eellison/76209c49d8829c5f1e323d34a3f040c3

bwd example: https://gist.github.com/eellison/6cfc2285df53a94cfa4012f5fdae5c51

Pull Request resolved: https://github.com/pytorch/pytorch/pull/163215
Approved by: https://github.com/IvanKobzarev

.ci/pytorch/multigpu-test.sh

@@ -26,6 +26,7 @@ if [[ "${SHARD_NUMBER:-2}" == "2" ]]; then
     time python test/run_test.py --verbose -i distributed/test_c10d_spawn_gloo
     time python test/run_test.py --verbose -i distributed/test_c10d_spawn_nccl
     time python test/run_test.py --verbose -i distributed/test_compute_comm_reordering
+    time python test/run_test.py --verbose -i distributed/test_aten_comm_compute_reordering
     time python test/run_test.py --verbose -i distributed/test_store
     time python test/run_test.py --verbose -i distributed/test_symmetric_memory
     time python test/run_test.py --verbose -i distributed/test_pg_wrapper

.ci/pytorch/test.sh

@@ -435,7 +435,7 @@ test_inductor_distributed() {
 
   # this runs on both single-gpu and multi-gpu instance. It should be smart about skipping tests that aren't supported
   # with if required # gpus aren't available
-  python test/run_test.py --include distributed/test_dynamo_distributed distributed/test_inductor_collectives distributed/test_compute_comm_reordering --verbose
+  python test/run_test.py --include distributed/test_dynamo_distributed distributed/test_inductor_collectives distributed/test_aten_comm_compute_reordering distributed/test_compute_comm_reordering --verbose
   assert_git_not_dirty
 }