chore(mem2reg): add a few regression tests

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

@@ -1723,6 +1723,33 @@ mod tests {
         assert_ssa_does_not_change(src, Ssa::mem2reg);
     }
 
+    #[test]
+    fn store_to_reference_from_array_get_is_not_lost() {
+        // `store Field 9 at v7` was incorrectly removed because of a bug
+        let src = "
+        brillig(inline) fn main f0 {
+          b0(v0: u1):
+            v2 = allocate -> &mut Field
+            store Field 0 at v2
+            jmpif v0 then: b1, else: b2
+          b1():
+            v5 = make_array [v2] : [&mut Field; 1]
+            jmp b3(v5)
+          b2():
+            v4 = make_array [v2] : [&mut Field; 1]
+            jmp b3(v4)
+          b3(v1: [&mut Field; 1]):
+            v7 = array_get v1, index u32 0 -> &mut Field
+            store Field 9 at v7
+            v9 = array_get v1, index u32 0 -> &mut Field
+            v10 = load v9 -> Field
+            constrain v10 == Field 9
+            return
+        }
+        ";
+        assert_ssa_does_not_change(src, Ssa::mem2reg);
+    }
+
     #[test]
     fn aliases_block_parameter_to_its_argument() {
         // Here:

test_programs/compile_success_empty/regression_9398/Nargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "regression_9398"
+type = "bin"
+authors = [""]
+compiler_unstable_features = ["enums"]
+
+
+[dependencies]

test_programs/compile_success_empty/regression_9398/src/main.nr

@@ -0,0 +1,13 @@
+fn main() {
+    let string = &mut "OOPS";
+    let param = [string];
+    assert_eq(*param[0], "OOPS");
+    foo(param);
+    assert_eq(*param[0], "GOOD");
+}
+
+fn foo(param: [&mut str<4>; 1]) {
+    let s = param[0];
+    *s = "GOOD";
+    for _ in 0..1 {}
+}

test_programs/execution_success/regression_9415/Nargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "regression_9415"
+type = "bin"
+authors = [""]
+compiler_unstable_features = ["enums"]
+
+
+[dependencies]

test_programs/execution_success/regression_9415/Prover.toml

@@ -0,0 +1 @@
+index = 0

test_programs/execution_success/regression_9415/src/main.nr

@@ -0,0 +1,8 @@
+unconstrained fn main(index: u32) {
+    let v0 = &mut 1;
+    let v1 = &mut 2;
+    let mut v3 = [v0];
+    v3[index] = v1;
+    *v3[index] = 3;
+    assert_eq(*v3[index], 3);
+}

test_programs/execution_success/regression_9439/Nargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "regression_9439"
+type = "bin"
+authors = [""]
+compiler_unstable_features = ["enums"]
+
+
+[dependencies]

test_programs/execution_success/regression_9439/Prover.toml

@@ -0,0 +1 @@
+n = 1

test_programs/execution_success/regression_9439/src/main.nr

@@ -0,0 +1,10 @@
+unconstrained fn main(n: u32) {
+    let num1 = &mut 0;
+    let mut slice = &[];
+    for _ in 0..n {
+        slice = slice.push_back(num1);
+    }
+    *slice[0] = 9;
+    assert_eq(*slice[0], 9);
+    assert_eq(*num1, 9);
+}

test_programs/execution_success/regression_9455/Nargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "regression_9455"
+type = "bin"
+authors = [""]
+compiler_unstable_features = ["enums"]
+
+
+[dependencies]

test_programs/execution_success/regression_9455/Prover.toml

@@ -0,0 +1 @@
+predicate = true

test_programs/execution_success/regression_9455/src/main.nr

@@ -0,0 +1,6 @@
+unconstrained fn main(predicate: bool) {
+    let num1 = &mut 0;
+    let array = if predicate { [num1] } else { [num1] };
+    *array[0] = 9;
+    assert_eq(*array[0], 9);
+}