[quant][fx] Fix dynamic weighted op lowering when input is used multiple times (#74364)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/74364
if a input is used multiple times in modules that are dynamically quantized:
```
x -- linear1
\-- linear2
```
we'll insert quantize_per_tensor_dynamic and dequantize for input, and we'll have a duplicate pass
to duplicate dequantize ops for pattern matching:
```
x - quantize_per_tensor_dynamic - dequantize1 - linear1
\----- dequantize2 - linear2
```
But we also have a check in the lowering code that if quantize_per_tensor_dynamic is used by multiple nodes
we'll skip the pattern, so the pattern is not recognized, we need to duplicate quantize_per_tensor_dynamic as well in this case
to recover both patterns:
```
x - quantize_per_tensor_dynamic1 -- dequantize1 -- linear1
\- quantize_per-tensor_dynamic2 -- dequantize2 -- linear2
```
so that they can be fused into dynamic linear:
```
x - linear_dynamic1
\-- linear_dynamic2
```
Test Plan:
python test/test_quantization.py TestQuantizeFx.test_dynamic_linear_input_multiple_use
Imported from OSS
Reviewed By: yixin94
Differential Revision: D34952755
fbshipit-source-id: a950159fd6a661e84faf0baf1692f6783904cfb3
(cherry picked from commit 8a6896801fdd96a55476faca4ccb7ba0b0bdb058)
