Eliminate tuples in preprocessing (#202)

This started as an optimization patch, but my first optimization
revealed a bug. In chasing the bug, I found more optimization.

Changes:
1. Eliminate tuples in preprocessing. (opt)
2. Handle CStore in tuple elimination pass. (bugfix)
3. Use tuples instead of arrays in a few more extension ops: (opt)
  * GCD for vanishing polynomials and their derivatives
  * sorting in transcript checking
4. A few logging revisions

examples/ZoKrates/pf/mem/2024_05_31_benny_bug_tr.zok.vin

@@ -1,7 +1,7 @@
 (set_default_modulus 52435875175126190479447740508185965837690552500527637822603658699938581184513
 (let (
     (x #f6)
-    (return #f6)
+    (return #f0)
 ) false ; ignored
 ))
 

examples/circ.rs

@@ -195,6 +195,7 @@ fn main() {
         Backend::Smt { .. } => Mode::Proof,
     };
     let language = determine_language(&options.frontend.language, &options.path);
+    println!("Running frontend");
     let cs = match language {
         #[cfg(all(feature = "smt", feature = "zok"))]
         DeterminedLanguage::Zsharp => {
@@ -233,6 +234,7 @@ fn main() {
             panic!("Missing feature: c");
         }
     };
+    println!("Running IR optimizations");
     let cs = match mode {
         Mode::Opt => opt(
             cs,
@@ -295,8 +297,7 @@ fn main() {
             opt(cs, opts)
         }
     };
-    println!("Done with IR optimization");
-
+    println!("Running backend");
     match options.backend {
         #[cfg(feature = "r1cs")]
         Backend::R1cs {
@@ -306,15 +307,14 @@ fn main() {
             proof_impl,
             ..
         } => {
-            println!("Converting to r1cs");
             let cs = cs.get("main");
             trace!("IR: {}", circ::ir::term::text::serialize_computation(cs));
             let mut r1cs = to_r1cs(cs, cfg());
             if cfg().r1cs.profile {
                 println!("R1CS stats: {:#?}", r1cs.stats());
             }
 
-            println!("Pre-opt R1cs size: {}", r1cs.constraints().len());
+            println!("Running r1cs optimizations ");
             r1cs = reduce_linearities(r1cs, cfg());
 
             println!("Final R1cs size: {}", r1cs.constraints().len());
@@ -326,7 +326,7 @@ fn main() {
                 ProofAction::Count => (),
                 #[cfg(feature = "bellman")]
                 ProofAction::Setup => {
-                    println!("Generating Parameters");
+                    println!("Running Setup");
                     match proof_impl {
                         ProofImpl::Groth16 => Bellman::<Bls12>::setup_fs(
                             prover_data,
@@ -348,7 +348,7 @@ fn main() {
                 ProofAction::Setup => panic!("Missing feature: bellman"),
                 #[cfg(feature = "bellman")]
                 ProofAction::CpSetup => {
-                    println!("Generating Parameters");
+                    println!("Running CpSetup");
                     match proof_impl {
                         ProofImpl::Groth16 => panic!("Groth16 is not CP"),
                         ProofImpl::Mirage => Mirage::<Bls12>::cp_setup_fs(

scripts/zokrates_test.zsh

@@ -72,8 +72,6 @@ function pf_test_isolate {
     done
 }
 
-pf_test 2024_05_24_benny_bug
-pf_test 2024_05_31_benny_bug
 r1cs_test_count ./examples/ZoKrates/pf/mm4_cond.zok 120
 r1cs_test ./third_party/ZoKrates/zokrates_stdlib/stdlib/ecc/edwardsAdd.zok
 r1cs_test ./third_party/ZoKrates/zokrates_stdlib/stdlib/ecc/edwardsOnCurve.zok
@@ -110,4 +108,7 @@ pf_test var_idx_arr_str_arr_str
 pf_test mm
 pf_test unused_var
 
+pf_test 2024_05_24_benny_bug
+pf_test 2024_05_31_benny_bug
+
 scripts/zx_tests/run_tests.sh

src/ir/opt/mem/ram/checker.rs

@@ -213,9 +213,7 @@ fn range_check(
     debug_assert!(values.iter().all(|v| check(v) == f_sort));
     let mut ms_hash_inputs = values.clone();
     values.extend(f_sort.elems_iter().take(n));
-    let sorted_term = unmake_array(
-        term![Op::ExtOp(ExtOp::Sort); make_array(f_sort.clone(), f_sort.clone(), values.clone())],
-    );
+    let sorted_term = tuple_terms(term![Op::ExtOp(ExtOp::Sort); term(Op::Tuple, values.clone())]);
     let sorted: Vec<Term> = sorted_term
         .into_iter()
         .enumerate()
@@ -302,10 +300,7 @@ fn derivative_gcd(
     let ns = ns.subspace("uniq");
     let fs = Sort::Field(f.clone());
     let pairs = term(
-        Op::Array(Box::new(ArrayOp {
-            key: fs.clone(),
-            val: Sort::new_tuple(vec![fs.clone(), Sort::Bool]),
-        })),
+        Op::Tuple,
         values
             .clone()
             .into_iter()
@@ -314,8 +309,8 @@ fn derivative_gcd(
             .collect(),
     );
     let two_polys = term![Op::ExtOp(ExtOp::UniqDeriGcd); pairs];
-    let s_coeffs = unmake_array(term![Op::Field(0); two_polys.clone()]);
-    let t_coeffs = unmake_array(term![Op::Field(1); two_polys]);
+    let s_coeffs = tuple_terms(term![Op::Field(0); two_polys.clone()]);
+    let t_coeffs = tuple_terms(term![Op::Field(1); two_polys]);
     let mut decl_poly = |coeffs: Vec<Term>, poly_name: &str| -> Vec<Term> {
         coeffs
             .into_iter()

src/ir/opt/mem/ram/checker/permutation.rs

@@ -11,19 +11,15 @@ pub(super) fn waksman(
     val_sort: &Sort,
     new_var: &mut impl FnMut(&str, Term) -> Term,
 ) -> Vec<Access> {
-    let f = &cfg.field;
-    let f_s = Sort::Field(f.clone());
     // (1) sort the transcript
     let field_tuples: Vec<Term> = accesses.iter().map(|a| a.to_field_tuple(cfg)).collect();
-    let switch_settings_tuple = term![Op::ExtOp(ExtOp::Waksman); make_array(f_s.clone(), check(&field_tuples[0]), field_tuples.clone())];
-    let n = check(&switch_settings_tuple).as_tuple().len();
-    let mut switch_settings: VecDeque<Term> = (0..n)
-        .map(|i| {
-            new_var(
-                &format!("sw{}", i),
-                term![Op::Field(i); switch_settings_tuple.clone()],
-            )
-        })
+    let switch_settings_tuple =
+        term![Op::ExtOp(ExtOp::Waksman); term(Op::Tuple, field_tuples.clone())];
+    let switch_settings_terms = tuple_terms(switch_settings_tuple);
+    let mut switch_settings: VecDeque<Term> = switch_settings_terms
+        .into_iter()
+        .enumerate()
+        .map(|(i, t)| new_var(&format!("sw{}", i), t))
         .collect();
 
     let sorted_field_tuple_values: Vec<Term> =
@@ -69,12 +65,10 @@ pub(super) fn msh(
     assertions: &mut Vec<Term>,
 ) -> Vec<Access> {
     let f = &cfg.field;
-    let f_s = Sort::Field(f.clone());
     // (1) sort the transcript
     let field_tuples: Vec<Term> = accesses.iter().map(|a| a.to_field_tuple(cfg)).collect();
-    let sorted_field_tuple_values: Vec<Term> = unmake_array(
-        term![Op::ExtOp(ExtOp::Sort); make_array(f_s.clone(), check(&field_tuples[0]), field_tuples.clone())],
-    );
+    let sorted_field_tuple_values: Vec<Term> =
+        tuple_terms(term![Op::ExtOp(ExtOp::Sort); term(Op::Tuple, field_tuples.clone())]);
     let mut sorted_accesses: Vec<Access> = sorted_field_tuple_values
         .into_iter()
         .enumerate()

src/ir/opt/mem/ram/volatile.rs

@@ -106,7 +106,7 @@ impl ArrayGraph {
                 .collect();
             while let Some(top) = stack.pop() {
                 if ram_terms.insert(top.clone()) {
-                    trace!("Maybe RAM: {}", top);
+                    trace!("Maybe RAM: {}", top.op());
                     for p in ps.get(&top).unwrap() {
                         if right_sort(p, field) {
                             stack.push(p.clone());

src/ir/opt/tuple.rs

@@ -143,6 +143,7 @@ impl TupleTree {
             }
         }
     }
+    #[track_caller]
     fn unwrap_non_tuple(self) -> Term {
         match self {
             TupleTree::NonTuple(t) => t,
@@ -245,9 +246,13 @@ fn tuple_free(t: Term) -> bool {
 /// Run the tuple elimination pass.
 pub fn eliminate_tuples(cs: &mut Computation) {
     let mut lifted: TermMap<TupleTree> = TermMap::default();
-    let terms =
-        PostOrderIter::from_roots_and_skips(cs.outputs().iter().cloned(), Default::default());
-    // .chain(cs.precomputes.outputs().values().cloned()),
+    let terms = PostOrderIter::from_roots_and_skips(
+        cs.outputs()
+            .iter()
+            .cloned()
+            .chain(cs.precomputes.outputs().values().cloned()),
+        Default::default(),
+    );
     for t in terms {
         let mut cs: Vec<TupleTree> = t
             .cs()
@@ -270,6 +275,14 @@ pub fn eliminate_tuples(cs: &mut Computation) {
                 let eqs = zip_eq(a.flatten(), b.flatten()).map(|(a, b)| term![Op::Eq; a, b]);
                 TupleTree::NonTuple(term(AND, eqs.collect()))
             }
+            Op::CStore => {
+                let c = cs.pop().unwrap().unwrap_non_tuple();
+                let v = cs.pop().unwrap();
+                let i = cs.pop().unwrap().unwrap_non_tuple();
+                let a = cs.pop().unwrap();
+                debug_assert!(cs.is_empty());
+                a.bimap(|a, v| term![Op::CStore; a, i.clone(), v, c.clone()], &v)
+            }
             Op::Store => {
                 let v = cs.pop().unwrap();
                 let i = cs.pop().unwrap().unwrap_non_tuple();
@@ -321,11 +334,11 @@ pub fn eliminate_tuples(cs: &mut Computation) {
         .into_iter()
         .flat_map(|o| lifted.get(&o).unwrap().clone().flatten())
         .collect();
-    //    let os = cs.precomputes.outputs().clone();
-    //    for (name, old_term) in os {
-    //        let new_term = lifted.get(&old_term).unwrap().clone().as_term();
-    //        cs.precomputes.change_output(&name, new_term);
-    //    }
+    let os = cs.precomputes.outputs().clone();
+    for (name, old_term) in os {
+        let new_term = lifted.get(&old_term).unwrap().clone().as_term();
+        cs.precomputes.change_output(&name, new_term);
+    }
     #[cfg(debug_assertions)]
     for o in &cs.outputs {
         if let Some(t) = find_tuple_term(o.clone()) {

src/ir/term/ext/haboeck.rs

@@ -10,7 +10,7 @@
 use crate::ir::term::ty::*;
 use crate::ir::term::*;
 
-/// Type-check [super::ExtOp::UniqDeriGcd].
+/// Type-check [super::ExtOp::Haboeck].
 pub fn check(arg_sorts: &[&Sort]) -> Result<Sort, TypeErrorReason> {
     let &[haystack, needles] = ty::count_or_ref(arg_sorts)?;
     let (_n, value0) = ty::homogenous_tuple_or(haystack, "haystack must be a tuple")?;
@@ -21,7 +21,7 @@ pub fn check(arg_sorts: &[&Sort]) -> Result<Sort, TypeErrorReason> {
     Ok(haystack.clone())
 }
 
-/// Evaluate [super::ExtOp::UniqDeriGcd].
+/// Evaluate [super::ExtOp::Haboeck].
 pub fn eval(args: &[&Value]) -> Value {
     let haystack: Vec<FieldV> = args[0]
         .as_tuple()

src/ir/term/ext/poly.rs

@@ -11,40 +11,24 @@ use crate::ir::term::*;
 
 /// Type-check [super::ExtOp::UniqDeriGcd].
 pub fn check(arg_sorts: &[&Sort]) -> Result<Sort, TypeErrorReason> {
-    if let &[pairs] = arg_sorts {
-        let (key, value, size) = ty::array_or(pairs, "UniqDeriGcd pairs")?;
-        let f = pf_or(key, "UniqDeriGcd pairs: indices must be field")?;
-        let value_tup = ty::tuple_or(value, "UniqDeriGcd entries: value must be a tuple")?;
-        if let &[root, cond] = &value_tup {
-            eq_or(f, root, "UniqDeriGcd pairs: first element must be a field")?;
-            eq_or(
-                cond,
-                &Sort::Bool,
-                "UniqDeriGcd pairs: second element must be a bool",
-            )?;
-            let arr = Sort::new_array(f.clone(), f.clone(), size);
-            Ok(Sort::new_tuple(vec![arr.clone(), arr]))
-        } else {
-            // non-pair entries value
-            Err(TypeErrorReason::Custom(
-                "UniqDeriGcd: pairs value must be a pair".into(),
-            ))
-        }
-    } else {
-        // wrong arg count
-        Err(TypeErrorReason::ExpectedArgs(2, arg_sorts.len()))
-    }
+    let [pairs] = ty::count_or_ref(arg_sorts)?;
+    let (size, value) = ty::homogenous_tuple_or(pairs, "UniqDeriGcd")?;
+    let [root, cond] = ty::count_or(ty::tuple_or(value, "UniqDeriGcd")?)?;
+    let f = pf_or(root, "UniqDeriGcd: first is field")?;
+    eq_or(cond, &Sort::Bool, "UniqDeriGcd pairs: second is bool")?;
+    let coeffs = Sort::new_tuple(vec![f.clone(); size]);
+    Ok(Sort::new_tuple(vec![coeffs.clone(), coeffs]))
 }
 
 /// Evaluate [super::ExtOp::UniqDeriGcd].
 #[cfg(feature = "poly")]
 pub fn eval(args: &[&Value]) -> Value {
     use rug_polynomial::ModPoly;
-    let sort = args[0].sort().as_array().0.clone();
+    let sort = args[0].sort().as_tuple()[0].as_tuple()[0].clone();
     let field = sort.as_pf().clone();
     let mut roots: Vec<Integer> = Vec::new();
-    let deg = args[0].as_array().size;
-    for t in args[0].as_array().values() {
+    let deg = args[0].as_tuple().len();
+    for t in args[0].as_tuple() {
         let tuple = t.as_tuple();
         let cond = tuple[1].as_bool();
         if cond {
@@ -60,7 +44,7 @@ pub fn eval(args: &[&Value]) -> Value {
         let v: Vec<Value> = (0..deg)
             .map(|i| Value::Field(field.new_v(s.get_coefficient(i))))
             .collect();
-        Value::Array(Array::from_vec(sort.clone(), sort.clone(), v))
+        Value::Tuple(v.into())
     };
     let s_cs = coeff_arr(s);
     let t_cs = coeff_arr(t);

src/ir/term/ext/sort.rs

@@ -17,12 +17,21 @@ pub fn check(arg_sorts: &[&Sort]) -> Result<Sort, TypeErrorReason> {
 /// Evaluate [super::ExtOp::Sort].
 pub fn eval(args: &[&Value]) -> Value {
     let sort = args[0].sort();
-    let (key_sort, value_sort, _) = sort.as_array();
-    let mut values: Vec<Value> = args[0].as_array().values();
+    let is_array = sort.is_array();
+    let mut values: Vec<Value> = if is_array {
+        args[0].as_array().values()
+    } else {
+        args[0].as_tuple().to_vec()
+    };
     values.sort();
-    Value::Array(Array::from_vec(
-        key_sort.clone(),
-        value_sort.clone(),
-        values,
-    ))
+    if is_array {
+        let (key_sort, value_sort, _) = sort.as_array();
+        Value::Array(Array::from_vec(
+            key_sort.clone(),
+            value_sort.clone(),
+            values,
+        ))
+    } else {
+        Value::Tuple(values.into())
+    }
 }

src/ir/term/ext/test.rs

@@ -25,7 +25,7 @@ fn uniq_deri_gcd_eval() {
     let t = text::parse_term(
         b"
         (declare (
-         (pairs (array (mod 17) (tuple (mod 17) bool) 5))
+         (pairs (tuple 5 (tuple (mod 17) bool)))
         )
          (uniq_deri_gcd pairs))",
     );
@@ -35,7 +35,7 @@ fn uniq_deri_gcd_eval() {
         (set_default_modulus 17
         (let
         (
-            (pairs (#l (mod 17) ( (#t #f0 false) (#t #f1 false) (#t #f2 true) (#t #f3 false) (#t #f4 true) )))
+            (pairs (#t (#t #f0 false) (#t #f1 false) (#t #f2 true) (#t #f3 false) (#t #f4 true) ))
         ) false))
         ",
     );
@@ -46,8 +46,8 @@ fn uniq_deri_gcd_eval() {
         (let
         (
           (output (#t
-            (#l (mod 17) ( #f16 #f0 #f0 #f0 #f0 ) ) ; s, from sage
-            (#l (mod 17) ( #f7 #f9 #f0 #f0 #f0 ) ) ; t, from sage
+            (#t #f16 #f0 #f0 #f0 #f0 ) ; s, from sage
+            (#t #f7 #f9 #f0 #f0 #f0 ) ; t, from sage
           ))
         ) false))
         ",
@@ -59,7 +59,7 @@ fn uniq_deri_gcd_eval() {
         (set_default_modulus 17
         (let
         (
-            (pairs (#l (mod 17) ( (#t #f0 true) (#t #f1 true) (#t #f2 true) (#t #f3 false) (#t #f4 true) )))
+            (pairs (#t (#t #f0 true) (#t #f1 true) (#t #f2 true) (#t #f3 false) (#t #f4 true)))
         ) false))
         ",
     );
@@ -70,8 +70,8 @@ fn uniq_deri_gcd_eval() {
         (let
         (
           (output (#t
-            (#l (mod 17) ( #f8 #f9 #f16 #f0 #f0 ) ) ; s, from sage
-            (#l (mod 17) ( #f2 #f16 #f9 #f13 #f0 ) ) ; t, from sage
+            (#t #f8 #f9 #f16 #f0 #f0 ) ; s, from sage
+            (#t #f2 #f16 #f9 #f13 #f0 ) ; t, from sage
           ))
         ) false))
         ",