Solidity 0.8.x Gas Optimization: Calldata vs Memory for Read-Only Arguments

When designing smart contracts for low-traffic workloads, minimizing gas expenditure during function execution is a priority. Solidity 0.8.x provides different data locations for function parameters, specifically memory and calldata.

While calldata is documented as a non-modifiable, non-persistent area where function arguments are stored, the specific gas trade-offs occur when these arguments are passed to internal functions or used in complex logic. The goal is to determine the most efficient transition from memory to calldata for read-only inputs to avoid unnecessary memory allocation costs.

Given the EVM's 32-byte word operations, there is uncertainty regarding the tipping point where the cost of accessing calldata multiple times outweighs the initial cost of copying data into memory.

• Under what specific access patterns does calldata become less efficient than memory?
• How does the compiler's optimization run setting affect the gas cost of these data location choices in Solidity 0.8.x?