Fixes an issue of supporting two scalar arguments for `where` and other functions with similar set of arguments:

```
refs.where(a, 1, 0)
```

I had to skip `test_python_ref_executor` because the test causes a `Segmentation fault` when running with two scalars.
The issue csarofeen#1770 has been fixed csarofeen#1774, so we can lift the skip when its merged to the upstream.
Pull Request resolved: #80146
Approved by: https://github.com/ngimel

… (#80146)

Summary:
Fixes an issue of supporting two scalar arguments for `where` and other functions with similar set of arguments:

```
refs.where(a, 1, 0)
```

I had to skip `test_python_ref_executor` because the test causes a `Segmentation fault` when running with two scalars.
The issue csarofeen#1770 has been fixed csarofeen#1774, so we can lift the skip when its merged to the upstream.

Pull Request resolved: #80146
Approved by: https://github.com/ngimel

Test Plan: contbuild & OSS CI, see https://hud.pytorch.org/commit/pytorch/pytorch/74fb6ee4c5303da9980bb6658d4989fbba0c9432

Reviewed By: b0noI

Differential Revision: D37536899

fbshipit-source-id: eb01318424186cc9205408fbbd61ef23da9e87d5

Syncing nvfuser devel branch to upstream master. https://github.com/csarofeen/pytorch/

Code changes includes:

- TransformPropagator refactor: switched to Dijkstra instead of exhaustive enumeration on all possible paths to reduce compilation time on transform propagation;
- Indexing refactor: remove reference tensor creation in all tensor indexing logic (csarofeen#1690)
- (more) generic grouped grid reduction kernel;
- Minor parser/fuser patches:
  1. zero-dim tensor reduction support
  3. no-op binary removal within fused graph
  4. expand supported in fusion

Squashed commits to WAR github API
Commits that's actually in this PR from the devel branch:

```
a054b3e Refactor TransormPropagator to allow specifying a position and propagating to part of the DAG (csarofeen#1775)
d67e1cd Indexing refactor stage 1: remove reference tensor creation in all tensor indexing logic (csarofeen#1690)
1b65299 Issue 1770 (csarofeen#1774)
35b0427 Avoid compilation errors like below: (csarofeen#1773)
452c773 Ignore reductions of zero-dim tensors per PyTorch conventions (csarofeen#1771)
31d6c56 TransformPropagator refactor (csarofeen#1769)
570c5a8 Merge pull request csarofeen#1767 from csarofeen/upstream_merge_0621
9d6c3d8 merging upstream 61305cd
0ed815f New TransformPropagator algorithm (csarofeen#1763)
6c19520 no-op binary removal (csarofeen#1764)
ec7fa41 Proper propagation of IterType (csarofeen#1762)
b263562 Fix dimensionality check (csarofeen#1759)
2d6343f More generic grouped grid reduction kernel (csarofeen#1740)
64e2b56 [nvfuser] prevent spamming warning message (pytorch#77777) (csarofeen#1758)
0c43162 [nvFuser] Improving bitwise ops support (pytorch#77158) (csarofeen#1757)
b93a147 Parser expand (csarofeen#1754)
```

RUN_TORCHBENCH: nvfuser
Pull Request resolved: pytorch#80355
Approved by: https://github.com/davidberard98

…ch#80146)

Fixes an issue of supporting two scalar arguments for `where` and other functions with similar set of arguments:

```
refs.where(a, 1, 0)
```

I had to skip `test_python_ref_executor` because the test causes a `Segmentation fault` when running with two scalars.
The issue csarofeen#1770 has been fixed csarofeen#1774, so we can lift the skip when its merged to the upstream.
Pull Request resolved: pytorch#80146
Approved by: https://github.com/ngimel