Refactor to allow use as library, in order to allow build.rs usage.

cranelift/isle/src/bin/isle.rs

@@ -1,15 +1,6 @@
-#![allow(dead_code)]
-
 use clap::{App, Arg};
 
-mod ast;
-mod codegen;
-mod compile;
-mod error;
-mod ir;
-mod lexer;
-mod parser;
-mod sema;
+use isle::{error, lexer, parser, compile};
 
 fn main() -> Result<(), error::Error> {
     let _ = env_logger::try_init();
@@ -73,3 +64,4 @@ fn main() -> Result<(), error::Error> {
 
     Ok(())
 }
+

cranelift/isle/src/ir.rs

@@ -477,10 +477,6 @@ impl ExprSequence {
         });
     }
 
-    fn add_multi_return(&mut self, index: usize, ty: TypeId, value: Value) {
-        self.add_inst(ExprInst::Return { index, ty, value });
-    }
-
     /// Creates a sequence of ExprInsts to generate the given
     /// expression value. Returns the value ID as well as the root
     /// term ID, if any.

cranelift/isle/src/lexer.rs

@@ -12,12 +12,6 @@ pub struct Lexer<'a> {
     lookahead: Option<(Pos, Token)>,
 }
 
-#[derive(Clone, Debug)]
-enum LexerInput<'a> {
-    String { s: &'a str, filename: &'a str },
-    File { content: String, filename: String },
-}
-
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Default, Hash, PartialOrd, Ord)]
 pub struct Pos {
     pub file: usize,