ch4: add function optimization passes

1 files changed, 4 insertions, 1 deletions

diff --git a/src/codegen.rs b/src/codegen.rs
index 866aab7..0a7893e 100644
--- a/src/codegen.rs
+++ b/src/codegen.rs
@@ -1,6 +1,6 @@
 use std::collections::HashMap;
 
-use crate::llvm::{Builder, FnValue, Module, Value};
+use crate::llvm::{Builder, FnValue, FunctionPassManager, Module, Value};
 use crate::parser::{ExprAST, FunctionAST, PrototypeAST};
 use crate::Either;
 
@@ -10,6 +10,7 @@ type CodegenResult<T> = Result<T, String>;
 pub struct Codegen<'llvm, 'a> {
     module: &'llvm Module,
     builder: &'a Builder<'llvm>,
+    fpm: &'a FunctionPassManager<'llvm>,
 }
 
 impl<'llvm, 'a> Codegen<'llvm, 'a> {
@@ -21,6 +22,7 @@ impl<'llvm, 'a> Codegen<'llvm, 'a> {
         let cg = Codegen {
             module,
             builder: &Builder::with_ctx(module),
+            fpm: &FunctionPassManager::with_ctx(module),
         };
         let mut variables = HashMap::new();
 
@@ -127,6 +129,7 @@ impl<'llvm, 'a> Codegen<'llvm, 'a> {
         if let Ok(ret) = self.codegen_expr(body, named_values) {
             self.builder.ret(ret);
             assert!(the_function.verify());
+            self.fpm.run(the_function);
             Ok(the_function)
         } else {
             todo!("Failed to codegen function body, erase from module!");