08f7e32a6e
This adds `unaligned-scalar-mem` as an allowed RISC-V target feature. Some RISC-V cores support unaligned access to memory without trapping. On such cores, the compiler could significantly improve code-size and performance when using functions like core::ptr::read_unaligned<u32> by emitting a single load or store instruction with an unaligned address, rather than a long sequence of byte load/store/bitmanip instructions. Enabling the `unaligned-scalar-mem` target feature allows LLVM to do this optimization. Fixes #110883
Please read the rustc-dev-guide chapter on Backend Agnostic Codegen.