[fx] refactored the file structure of patched function and module (#1238)

* [fx] refactored the file structure of patched function and module

* polish code

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

@@ -0,0 +1,63 @@
+import torch
+from ..registry import meta_patched_function
+
+
+@meta_patched_function.register(torch.matmul)
+def torch_matmul(input, other, *, out=None):
+    # copied from huggingface.utils.fx
+    d1 = input.dim()
+    d2 = other.dim()
+    shape = None
+    if d1 == 1 and d2 == 1:
+        shape = None
+    elif d1 == 2 and d2 == 2:
+        shape = (input.size(0), other.size(1))
+    elif d1 == 1 and d2 == 2:
+        shape = (other.size(1),)
+    elif d1 == 2 and d1 == 1:
+        shape = (input.size(0),)
+    else:
+        max_length = max(input.dim(), other.dim())
+        shape1 = list(input.shape)
+        shape2 = list(other.shape)
+        if d1 == 1:
+            shape1 = [1] + shape1
+        if d2 == 1:
+            shape2.append(1)
+        shape1 = [-1] * (max_length - d1) + list(input.shape)
+        shape2 = [-1] * (max_length - d2) + list(other.shape)
+        shape = []
+        for i in range(max_length):
+            shape.append(max(shape1[i], shape2[i]))
+        shape[-2] = shape1[-2]
+        shape[-1] = shape2[-1]
+        if d1 == 1:
+            shape.pop(-2)
+        if d2 == 1:
+            shape.pop(-1)
+    if shape is None:
+        return torch.tensor(0.0, device="meta")
+    return torch.empty(*shape, device="meta")
+
+
+@meta_patched_function.register(torch.abs)
+def torch_abs(input, *, out=None):
+    assert out is None, 'out is not supported yet'
+    return torch.empty(input.shape, device='meta')
+
+
+@meta_patched_function.register(torch.bmm)
+def torch_bmm(input, mat2, *, out=None):
+    if out is not None:
+        raise ValueError("Don't support in-place abs for MetaTensor analysis")
+    batch_size, n, m = input.shape
+    _, _, p = mat2.shape
+    return torch.empty(batch_size, n, p, device="meta")
+
+
+@meta_patched_function.register(torch.var_mean)
+def torch_var_mean(input, dim, unbiased=True, keepdim=False, *, out=None):
+    assert out is None, 'saving to out is not supported yet'
+    var = torch.empty(1).squeeze(0).to('meta')
+    mean = torch.empty(1).squeeze(0).to('meta')
+    return var, mean