[fx] refactor tracer to trace complete graph (#1342)

* [CLI] add CLI launcher

* Revert "[CLI] add CLI launcher"

This reverts commit df7e6506d4.

* [fx] refactor tracer to trace complete graph

* add comments and solve conflicts.

colossalai/fx/tracer/meta_patch/patched_function/torch_ops.py

@@ -24,6 +24,11 @@ def torch_arange(*args, **kwargs):
     return torch.empty((end - start) // step, dtype=dtype, device="meta")
 
 
+@meta_patched_function.register(torch.finfo)
+def torch_finfo(*args):
+    return torch.finfo(*args)
+
+
 @meta_patched_function.register(torch.where)
 def torch_where(condition, x, y):
     # torch.where returns the broadcasted tensor of condition, x, and y,