7ebff82861
* Optimize sign extension via shifts This commit adds egraph optimization patterns for left-shifting a value and then right-shifting it as a form of sign extending its lower bits. This matches the behavior of the WebAssembly `i32.extend8_s` instruction, for example. Note that the lowering of that WebAssembly instruction does not use shifts, but historical versions of LLVM that didn't support the instruction, or versions with the instruction disabled, will use shifts instead. A second rule for reduction-of-extend being the same as the original value was added to keep an existing shift-related test passing as well. * Add reference assemblies for new opts
This crate contains the core Cranelift code generator. It translates code from an intermediate representation into executable machine code.