456561f431
The StructReturn ABI is fairly simple at the codegen/isel level: we only need to take care to return the sret pointer as one of the return values if that wasn't specified in the initial function signature. Struct arguments are a little more complex. A struct argument is stored as a chunk of memory in the stack-args space. However, the CLIF semantics are slightly special: on the caller side, the parameter passed in is a pointer to an arbitrary memory block, and we must memcpy this data to the on-stack struct-argument; and on the callee side, we provide a pointer to the passed-in struct-argument as the CLIF block param value. This is necessary to support various ABIs other than Wasm, such as that of Rust (with the cg_clif codegen backend).
This crate contains the core Cranelift code generator. It translates code from an intermediate representation into executable machine code.