You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: func_environ.rs
    path of file: ./repos/wasmer/lib/compiler-cranelift/src
    
    the code of the file until where you have to start completion: // This file contains code from external sources.
// Attributions: https://github.com/wasmerio/wasmer/blob/master/ATTRIBUTIONS.md

use crate::translator::{
    type_to_irtype, FuncEnvironment as BaseFuncEnvironment, GlobalVariable, TargetEnvironment,
};
use cranelift_codegen::cursor::FuncCursor;
use cranelift_codegen::ir;
use cranelift_codegen::ir::condcodes::*;
use cranelift_codegen::ir::immediates::{Offset32, Uimm64};
use cranelift_codegen::ir::types::*;
use cranelift_codegen::ir::{AbiParam, ArgumentPurpose, Function, InstBuilder, Signature};
use cranel
    
    fn get_memory32_atomic_wait64_sig(&mut self, func: &mut Function) -> ir::SigRef {
        let sig = self.memory32_atomic_wait64_sig.unwrap_or_else(|| {
            func.import_signature(Signature {
                params: vec![
                    AbiParam::special(self.pointer_type(), ArgumentPurpose::VMContext),
                    // Memory Index
                    AbiParam::new(I32),
                    // Dst
                    AbiParam::new(I32),
                    // Val
                    AbiParam::new(I64),
                    // Timeout
                    AbiParam::new(I64),
                ],
                returns: vec![AbiParam::new(I32)],
                call_conv: self.target_config.default_call_conv,
            })
        });
        self.memory32_atomic_wait64_sig = Some(sig);
        sig
    }