chore(ssa refactor): Add basic binary operation program

crates/nargo_cli/tests/test_data_ssa_refactor/simple_program_addition/Nargo.toml

@@ -0,0 +1,5 @@
+[package]
+authors = [""]
+compiler_version = "0.1"
+
+[dependencies]

crates/nargo_cli/tests/test_data_ssa_refactor/simple_program_addition/Prover.toml

@@ -0,0 +1 @@
+x = "3"

crates/nargo_cli/tests/test_data_ssa_refactor/simple_program_addition/src/main.nr

@@ -0,0 +1,5 @@
+// The feature being tested is handling of
+// a binary operation.
+fn main(x : Field) -> pub Field {
+    x + 1
+}

crates/noirc_evaluator/src/ssa_refactor/acir_gen/mod.rs

@@ -110,7 +110,10 @@ impl Context {
             _ => unreachable!("ICE: Program must have a singular return"),
         };
 
-        let is_return_unit_type = return_values.len() == 1 && dfg.type_of_value(return_values[0]) == Type::Unit;
+        // Check if the program returns the `Unit/None` type.
+        // This type signifies that the program returns nothing.
+        let is_return_unit_type =
+            return_values.len() == 1 && dfg.type_of_value(return_values[0]) == Type::Unit;
         if is_return_unit_type {
             return;
         }