From 2d321faa66e5a17d159c298a733e8b8560affe19 Mon Sep 17 00:00:00 2001
From: Tom French <15848336+TomAFrench@users.noreply.github.com>
Date: Wed, 13 Nov 2024 19:28:35 +0000
Subject: [PATCH] feat: parallelize DIE pass (#9933)

We can parallelize the DIE pass across different functions to speed up
this pass.
---
 noir/noir-repo/compiler/noirc_evaluator/src/ssa/opt/die.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/noir/noir-repo/compiler/noirc_evaluator/src/ssa/opt/die.rs b/noir/noir-repo/compiler/noirc_evaluator/src/ssa/opt/die.rs
index 57af27e8dcd..f28b076a5f9 100644
--- a/noir/noir-repo/compiler/noirc_evaluator/src/ssa/opt/die.rs
+++ b/noir/noir-repo/compiler/noirc_evaluator/src/ssa/opt/die.rs
@@ -3,6 +3,7 @@
 use fxhash::{FxHashMap as HashMap, FxHashSet as HashSet};
 use im::Vector;
 use noirc_errors::Location;
+use rayon::iter::{IntoParallelRefMutIterator, ParallelIterator};
 
 use crate::ssa::{
     ir::{
@@ -24,9 +25,8 @@ impl Ssa {
     /// unused results.
     #[tracing::instrument(level = "trace", skip(self))]
     pub(crate) fn dead_instruction_elimination(mut self) -> Ssa {
-        for function in self.functions.values_mut() {
-            function.dead_instruction_elimination(true);
-        }
+        self.functions.par_iter_mut().for_each(|(_, func)| func.dead_instruction_elimination(true));
+
         self
     }
 }