zk: add forgotten file in last commit tracer.rs

src/zk/tracer.rs

@@ -0,0 +1,72 @@
+use std::{
+    cell::RefCell,
+    ops::{Deref, DerefMut},
+};
+
+use darkfi_sdk::{crypto::constants::OrchardFixedBases, pasta::pallas};
+use halo2_gadgets::ecc as ecc_gadget;
+use halo2_proofs::{arithmetic::Field, circuit::AssignedCell};
+
+#[derive(Clone, Debug)]
+pub enum DebugOpValue {
+    EcPoint(pallas::Base, pallas::Base),
+    Base(pallas::Base),
+    Void,
+}
+
+#[derive(Clone)]
+pub struct ZkTracer {
+    pub opvalues: RefCell<Option<Vec<DebugOpValue>>>,
+    init_allowed: bool,
+}
+
+impl ZkTracer {
+    pub(crate) fn new(init_allowed: bool) -> Self {
+        Self { opvalues: RefCell::new(None), init_allowed }
+    }
+
+    pub(crate) fn init(&self) {
+        if !self.init_allowed {
+            return
+        }
+        *self.opvalues.borrow_mut() = Some(Vec::new());
+    }
+
+    pub(crate) fn clear(&self) {
+        if let Some(opvalues) = self.opvalues.borrow_mut().deref_mut() {
+            opvalues.clear();
+        }
+    }
+
+    pub(crate) fn push_ecpoint(
+        &self,
+        point: &ecc_gadget::Point<pallas::Affine, ecc_gadget::chip::EccChip<OrchardFixedBases>>,
+    ) {
+        if let Some(opvalues) = self.opvalues.borrow_mut().deref_mut() {
+            let (mut x, mut y) = (pallas::Base::ZERO, pallas::Base::ZERO);
+            point.inner().x().value().map(|rx| x = *rx);
+            point.inner().y().value().map(|ry| y = *ry);
+            opvalues.push(DebugOpValue::EcPoint(x, y));
+        }
+    }
+
+    pub(crate) fn push_base(&self, value: &AssignedCell<pallas::Base, pallas::Base>) {
+        if let Some(opvalues) = self.opvalues.borrow_mut().deref_mut() {
+            let mut x = pallas::Base::ZERO;
+            value.value().map(|rx| x = *rx);
+            opvalues.push(DebugOpValue::Base(x));
+        }
+    }
+
+    pub(crate) fn push_void(&self) {
+        if let Some(opvalues) = self.opvalues.borrow_mut().deref_mut() {
+            opvalues.push(DebugOpValue::Void);
+        }
+    }
+
+    pub(crate) fn assert_correct(&self, opcodes_len: usize) {
+        if let Some(opvalues) = self.opvalues.borrow().deref() {
+            assert_eq!(opvalues.len(), opcodes_len);
+        }
+    }
+}