🐛 [torch.export][llama2] Accuracy issues with llama model

[peri044]

Bug Description

The outputs of TRT compilation do not match with PyTorch for llama2 model. These are the causes for it.

1. Running in FP16 precision (layernorm warns about FP16 precision not being enough). So, we need to compile in FP32 precision

2. Rotation : https://github.com/huggingface/transformers/blob/main/src/transformers/models/llama/modeling_llama.py#L152-L156
   This block leads to output mismatch

3. Adding attention mask https://github.com/huggingface/transformers/blob/e65502951593a76844e872fee9c56b805598538a/src/transformers/models/llama/modeling_llama.py#L347-L349 These lines also cause output mismatch.

Compiling with dynamic shapes and FP32 also lead to high memory usage.

To Reproduce

Steps to reproduce the behavior:

Expected behavior

Environment

Build information about Torch-TensorRT can be found by turning on debug messages

• Torch-TensorRT Version (e.g. 1.0.0):
• PyTorch Version (e.g. 1.0):
• CPU Architecture:
• OS (e.g., Linux):
• How you installed PyTorch (conda, pip, libtorch, source):
• Build command you used (if compiling from source):
• Are you using local sources or building from archives:
• Python version:
• CUDA version:
• GPU models and configuration:
• Any other relevant information:

Additional context

[peri044]

If I enable strongly typed flag, I face the following error.

ERROR:torch_tensorrt [TensorRT Conversion Context]:10: setOutputType cannot be called for a strongly typed network.
ERROR:torch_tensorrt [TensorRT Conversion Context]:1: [network.cpp::setOutputType::757] Error Code 1: Internal Error (Invalid use of API - See recorded error for details.)

We use set_output_type for casting everywhere in our codebase which will be a problem.

[peri044]

This is fixed for FP32 precision in llm_examples_main PR : #3002