Prompt
When working with PyTorch tensors, look for opportunities to optimize operation chains for better performance and memory efficiency. This involves two key strategies:
- Use inplace operations when safe: For non-leaf tensors, inplace operations (+=, *=, etc.) can reduce memory allocation and improve performance. Check if a tensor is a leaf node before deciding:
def optimized_add(x: torch.Tensor, value: float) -> torch.Tensor:
if x.is_leaf:
x = x + value # Create new tensor for leaf nodes
else:
x += value # Inplace operation for non-leaf nodes
return x
- Mathematically simplify operation chains: Look for algebraically equivalent expressions that require fewer operations:
# Instead of: x.add(1.0).div(2.0).clamp(0,1).mul(255.).round()
# Use: x.add(1.0).clamp(0,2).mul(127.5).round()
# This eliminates one operation while maintaining mathematical correctness
These optimizations are particularly important in neural network forward/backward passes where tensor operations are performed repeatedly on large data. Always verify mathematical equivalence when simplifying operation chains, and profile performance gains in your specific use case.