feat(hints): Implement NewHint#59

CHANGELOG.md

@@ -2,6 +2,23 @@
 
 #### Upcoming Changes
 
+Add missing hint on vrf.json lib [#1053](https://github.com/lambdaclass/cairo-rs/pull/1053):
+
+     `BuiltinHintProcessor` now supports the following hint:
+
+     ```python
+    %{
+        from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
+        SECP_P = 2**255-19
+
+        slope = pack(ids.slope, PRIME)
+        x = pack(ids.point.x, PRIME)
+        y = pack(ids.point.y, PRIME)
+
+        value = new_x = (pow(slope, 2, SECP_P) - 2 * x) % SECP_P
+    %}
+     ```
+
 * Implement hint on ec_recover.json whitelist [#1038](https://github.com/lambdaclass/cairo-rs/pull/1038):
 
     `BuiltinHintProcessor` now supports the following hint:

cairo_programs/ec_double_assign_new_x_v3.cairo

@@ -0,0 +1,85 @@
+%builtins range_check
+from starkware.cairo.common.cairo_secp.bigint import BigInt3, nondet_bigint3, UnreducedBigInt3
+from starkware.cairo.common.cairo_secp.field import (
+    is_zero,
+    unreduced_sqr,
+    unreduced_mul
+)
+from starkware.cairo.common.cairo_secp.ec import EcPoint, compute_doubling_slope, verify_zero
+
+// Computes the addition of a given point to itself.
+//
+// Arguments:
+//   point - the point to operate on.
+//
+// Returns:
+//   res - a point representing point + point.
+func ec_double{range_check_ptr}(point: EcPoint) -> (res: EcPoint) {
+    // The zero point.
+    if (point.x.d0 == 0) {
+        if (point.x.d1 == 0) {
+            if (point.x.d2 == 0) {
+                return (res=point);
+            }
+        }
+    }
+
+    let (slope: BigInt3) = compute_doubling_slope(point);
+    let (slope_sqr: UnreducedBigInt3) = unreduced_sqr(slope);
+
+    %{
+        from starkware.cairo.common.cairo_secp.secp_utils import SECP_P, pack
+        SECP_P = 2**255-19
+
+        slope = pack(ids.slope, PRIME)
+        x = pack(ids.point.x, PRIME)
+        y = pack(ids.point.y, PRIME)
+
+        value = new_x = (pow(slope, 2, SECP_P) - 2 * x) % SECP_P
+    %}
+
+    let (new_x: BigInt3) = nondet_bigint3();
+
+    %{ value = new_y = (slope * (x - new_x) - y) % SECP_P %}
+    let (new_y: BigInt3) = nondet_bigint3();
+
+    verify_zero(
+        UnreducedBigInt3(
+            d0=slope_sqr.d0 - new_x.d0 - 2 * point.x.d0,
+            d1=slope_sqr.d1 - new_x.d1 - 2 * point.x.d1,
+            d2=slope_sqr.d2 - new_x.d2 - 2 * point.x.d2,
+        ),
+    );
+
+    let (x_diff_slope: UnreducedBigInt3) = unreduced_mul(
+        BigInt3(d0=point.x.d0 - new_x.d0, d1=point.x.d1 - new_x.d1, d2=point.x.d2 - new_x.d2), slope
+    );
+
+    verify_zero(
+        UnreducedBigInt3(
+            d0=x_diff_slope.d0 - point.y.d0 - new_y.d0,
+            d1=x_diff_slope.d1 - point.y.d1 - new_y.d1,
+            d2=x_diff_slope.d2 - point.y.d2 - new_y.d2,
+        ),
+    );
+
+    return (res=EcPoint(new_x, new_y));
+}
+
+func main{range_check_ptr}() {
+    let x = BigInt3(1,2,3);
+    let y = BigInt3(4,5,6);
+    let p = EcPoint(x, y);
+
+    let (r) = ec_double(p);
+
+    assert r.x.d0 = 57832968898037685942927716;
+    assert r.x.d1 = 27957507593122495312333579;
+    assert r.x.d2 = 876486538158111111042155;
+
+    assert r.y.d0 = 76653617457582133477854326;
+    assert r.y.d1 = 906421522066442687720656;
+    assert r.y.d2 = 11165193544924531831122323;
+
+    return ();
+}

src/hint_processor/builtin_hint_processor/builtin_hint_processor_definition.rs

@@ -4,6 +4,7 @@ use super::{
         ec_recover_sub_a_b,
     },
     field_arithmetic::uint384_div,
+    secp::secp_utils::{SECP_P, SECP_P_V2},
     vrf::{fq::uint512_unsigned_div_rem, inv_mod_p_uint512::inv_mod_p_uint512},
 };
 use crate::{
@@ -459,8 +460,21 @@ impl HintProcessor for BuiltinHintProcessor {
                 "pt1",
             ),
             hint_code::EC_DOUBLE_ASSIGN_NEW_X_V1 | hint_code::EC_DOUBLE_ASSIGN_NEW_X_V2 => {
-                ec_double_assign_new_x(vm, exec_scopes, &hint_data.ids_data, &hint_data.ap_tracking)
+                ec_double_assign_new_x(
+                    vm,
+                    exec_scopes,
+                    &hint_data.ids_data,
+                    &hint_data.ap_tracking,
+                    &SECP_P,
+                )
             }
+            hint_code::EC_DOUBLE_ASSIGN_NEW_X_V3 => ec_double_assign_new_x(
+                vm,
+                exec_scopes,
+                &hint_data.ids_data,
+                &hint_data.ap_tracking,
+                &SECP_P_V2,
+            ),
             hint_code::EC_DOUBLE_ASSIGN_NEW_Y => ec_double_assign_new_y(exec_scopes),
             hint_code::KECCAK_WRITE_ARGS => {
                 keccak_write_args(vm, &hint_data.ids_data, &hint_data.ap_tracking)

src/hint_processor/builtin_hint_processor/hint_code.rs

@@ -604,6 +604,15 @@ y = pack(ids.point.y, PRIME)
 
 value = new_x = (pow(slope, 2, SECP_P) - 2 * x) % SECP_P"#;
 
+pub const EC_DOUBLE_ASSIGN_NEW_X_V3: &str = r#"from starkware.cairo.common.cairo_secp.secp_utils import pack
+SECP_P = 2**255-19
+
+slope = pack(ids.slope, PRIME)
+x = pack(ids.point.x, PRIME)
+y = pack(ids.point.y, PRIME)
+
+value = new_x = (pow(slope, 2, SECP_P) - 2 * x) % SECP_P"#;
+
 pub const EC_DOUBLE_ASSIGN_NEW_Y: &str = r#"value = new_y = (slope * (x - new_x) - y) % SECP_P"#;
 
 pub const SHA256_INPUT: &str = r#"ids.full_word = int(ids.n_bytes >= 4)"#;

src/hint_processor/builtin_hint_processor/secp/ec_utils.rs

@@ -177,8 +177,9 @@ pub fn ec_double_assign_new_x(
     exec_scopes: &mut ExecutionScopes,
     ids_data: &HashMap<String, HintReference>,
     ap_tracking: &ApTracking,
+    secp_p: &BigInt,
 ) -> Result<(), HintError> {
-    exec_scopes.insert_value("SECP_P", SECP_P.clone());
+    exec_scopes.insert_value("SECP_P", secp_p.clone());
     //ids.slope
     let slope = BigInt3::from_var_name("slope", vm, ids_data, ap_tracking)?;
     //ids.point

src/hint_processor/builtin_hint_processor/secp/secp_utils.rs

@@ -27,6 +27,11 @@ lazy_static! {
         "115792089237316195423570985008687907853269984665640564039457584007908834671663"
     )
     .unwrap();
+    //SECP_P_V2 = 2**255-19
+    pub(crate) static ref SECP_P_V2: BigInt = BigInt::from_str(
+        "57896044618658097711785492504343953926634992332820282019728792003956564819949"
+    )
+    .unwrap();
     // BASE = 2**86
     pub(crate) static ref BASE: BigUint = BigUint::from_str(
         "77371252455336267181195264"

src/tests/cairo_run_test.rs

@@ -834,3 +834,10 @@ fn cairo_run_fq_test() {
     let program_data = include_bytes!("../../cairo_programs/fq_test.json");
     run_program_simple_with_memory_holes(program_data.as_slice(), 42);
 }
+
+#[test]
+#[cfg_attr(target_arch = "wasm32", wasm_bindgen_test)]
+fn ec_double_assing_new_x_v3() {
+    let program_data = include_bytes!("../../cairo_programs/ec_double_assing_new_x_v3.json");
+    run_program_simple(program_data.as_slice());
+}