chore: run two rounds of backpropagation

acvm-repo/acir/src/circuit/directives.rs

@@ -22,3 +22,12 @@ pub enum Directive {
         sort_by: Vec<u32>, // specify primary index to sort by, then the secondary,... For instance, if tuple is 2 and sort_by is [1,0], then a=[(a0,b0),..] is sorted by bi and then ai.
     },
 }
+
+impl Directive {
+    pub fn get_outputs_vec(&self) -> Vec<Witness> {
+        match self {
+            Directive::ToLeRadix { b, .. } => b.to_owned(),
+            Directive::PermutationSort { bits, .. } => bits.to_owned(),
+        }
+    }
+}

acvm-repo/acvm/src/compiler/optimizers/constant_backpropagation.rs

@@ -228,9 +228,17 @@ impl ConstantBackpropOptimizer {
                         }
                     };
 
-                    match solve_directives(&mut known_witnesses, &directive) {
-                        Ok(()) => continue,
-                        Err(_) => Opcode::Directive(directive),
+                    if directive
+                        .get_outputs_vec()
+                        .iter()
+                        .all(|output| known_witnesses.contains_key(output))
+                    {
+                        continue;
+                    } else {
+                        match solve_directives(&mut known_witnesses, &directive) {
+                            Ok(()) => continue,
+                            Err(_) => Opcode::Directive(directive),
+                        }
                     }
                 }
 

acvm-repo/acvm/src/compiler/optimizers/mod.rs

@@ -66,6 +66,9 @@ pub(super) fn optimize_internal(acir: Circuit) -> (Circuit, Vec<usize>) {
     let (acir, acir_opcode_positions) =
         range_optimizer.replace_redundant_ranges(acir_opcode_positions);
 
+    let (acir, acir_opcode_positions) =
+        ConstantBackpropOptimizer::backpropagate_constants(acir, acir_opcode_positions);
+
     info!("Number of opcodes after: {}", acir.opcodes.len());
 
     (acir, acir_opcode_positions)