fix(mem2reg): Keep last stores used in MakeArray

compiler/noirc_evaluator/src/ssa/opt/mem2reg.rs

@@ -140,6 +140,9 @@ struct PerFunctionContext<'f> {
     /// Track whether a reference was passed into another entry point
     /// This is needed to determine whether we can remove a store.
     calls_reference_input: HashSet<ValueId>,
+    /// Track whether a reference was passed into a make array instruction
+    /// This is needed to determine whether we can remove a store.
+    make_array_references: HashSet<ValueId>,
 
     /// Track whether a reference has been aliased, and store the respective
     /// instruction that aliased that reference.
@@ -161,6 +164,7 @@ impl<'f> PerFunctionContext<'f> {
             last_loads: HashMap::default(),
             calls_reference_input: HashSet::default(),
             aliased_references: HashMap::default(),
+            make_array_references: HashSet::default(),
         }
     }
 
@@ -245,6 +249,12 @@ impl<'f> PerFunctionContext<'f> {
                     return true;
                 }
 
+                let allocation_aliases_parameter =
+                    aliases.any(|alias| self.make_array_references.contains(&alias));
+                if allocation_aliases_parameter == Some(true) {
+                    return true;
+                }
+
                 let allocation_aliases_parameter =
                     aliases.any(|alias| all_terminator_values.contains(&alias));
                 if allocation_aliases_parameter == Some(true) {
@@ -551,6 +561,7 @@ impl<'f> PerFunctionContext<'f> {
 
                     for element in elements {
                         aliases.insert(*element);
+                        self.make_array_references.insert(*element);
                     }
                 }
             }

test_programs/execution_success/regression_8739/Nargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "regression_8739"
+type = "bin"
+authors = [""]
+
+[dependencies]

test_programs/execution_success/regression_8739/src/main.nr

@@ -0,0 +1,15 @@
+fn main() {
+    // Safety: testing context
+    unsafe {
+        func_2()
+    }
+}
+unconstrained fn func_2() {
+    let mut a: [&mut bool; 1] = [(&mut true)];
+    let mut idx_b: u32 = 0;
+    while (*a[0]) {
+        if (idx_b == 0) {
+            break;
+        }
+    }
+}