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use rand::prelude::*;
use triton_vm::prelude::*;
use twenty_first::math::polynomial::Polynomial;
use twenty_first::math::x_field_element::EXTENSION_DEGREE;
use crate::data_type::DataType;
use crate::empty_stack;
use crate::library::Library;
use crate::snippet_bencher::BenchmarkCase;
use crate::traits::basic_snippet::BasicSnippet;
use crate::traits::closure::Closure;
#[derive(Debug, Clone, Copy, Eq, PartialEq, Hash)]
pub struct CollinearYXfe;
impl BasicSnippet for CollinearYXfe {
fn inputs(&self) -> Vec<(DataType, String)> {
vec![
(DataType::Xfe, "p_2_x".to_owned()),
(DataType::Xfe, "p_1_y".to_owned()),
(DataType::Xfe, "p_1_x".to_owned()),
(DataType::Xfe, "p_0_y".to_owned()),
(DataType::Xfe, "p_0_x".to_owned()),
]
}
fn outputs(&self) -> Vec<(DataType, String)> {
vec![(DataType::Xfe, "p_2_y".to_owned())]
}
fn entrypoint(&self) -> String {
"tasmlib_verifier_fri_collinear_y_xfe".to_owned()
}
// Original:
// let dy = p0.1 - p1.1;
// let dx = p0.0 - p1.0;
// let p2_y_times_dx = dy * (p2_x - p0.0) + dx * p0.1;
// // Can we implement this without division?
// p2_y_times_dx / dx
// let dy = a_y - b_y;
// let dx = a_x - b_x;
// let p2_y_times_dx = dy * (c_x - a_x) + dx * a_y;
// p2_y_times_dx / dx
// So we want:
// p2_y_times_dx = ((a_y - b_y) * (c_x - a_x) + (a_x - b_x) * a_y) / dx
// Calculate the inner parenthesis first.
// So first (a_y - b_y), then (c_x - a_x), then
fn code(&self, _library: &mut Library) -> Vec<LabelledInstruction> {
triton_asm!(
// BEFORE: _ [p2x; 3] [p1y; 3] [p1x; 3] [p0y; 3] [p0x; 3]
// AFTER: _ [p2y; 3]
{self.entrypoint()}:
swap 9 // _ [p2x; 3] p1y2 p1y1 p0x0 [p1x; 3] [p0y; 3] p0x2 p0x1 p1y0
swap 1 // _ [p2x; 3] p1y2 p1y1 p0x0 [p1x; 3] [p0y; 3] p0x2 p1y0 p0x1
swap 10 // _ [p2x; 3] p1y2 p0x1 p0x0 [p1x; 3] [p0y; 3] p0x2 p1y0 p1y1
swap 2 // _ [p2x; 3] p1y2 p0x1 p0x0 [p1x; 3] [p0y; 3] p1y1 p1y0 p0x2
swap 11 // _ [p2x; 3] [p0x; 3] [p1x; 3] [p0y; 3] p1y1 p1y0 p1y2
swap 2 // _ [p2x; 3] [p0x; 3] [p1x; 3] [p0y; 3] p1y2 p1y0 p1y1
swap 1 // _ [p2x; 3] [p0x; 3] [p1x; 3] [p0y; 3] [p1y; 3]
dup 5 dup 5 dup 5
// _ [p2x; 3] [p0x; 3] [p1x; 3] [p0y; 3] [p1y; 3] [p0y; 3]
push -1
xb_mul // _ [p2x; 3] [p0x; 3] [p1x; 3] [p0y; 3] [p1y; 3] [-p0y; 3]
xx_add // _ [p2x; 3] [p0x; 3] [p1x; 3] [p0y; 3] [p1y - p0y; 3]
push -1
xb_mul // dy = p0y - p1y
// _ [p2x; 3] [p0x; 3] [p1x; 3] [p0y; 3] [dy; 3]
swap 6 // _ [p2x; 3] [p0x; 3] p1x2 p1x1 dy0 [p0y; 3] dy2 dy1 p1x0
swap 1 // _ [p2x; 3] [p0x; 3] p1x2 p1x1 dy0 [p0y; 3] dy2 p1x0 dy1
swap 7 // _ [p2x; 3] [p0x; 3] p1x2 dy1 dy0 [p0y; 3] dy2 p1x0 p1x1
swap 2 // _ [p2x; 3] [p0x; 3] p1x2 dy1 dy0 [p0y; 3] p1x1 p1x0 dy2
swap 8 // _ [p2x; 3] [p0x; 3] [dy; 3] [p0y; 3] p1x1 p1x0 p1x2
swap 2 // _ [p2x; 3] [p0x; 3] [dy; 3] [p0y; 3] p1x2 p1x0 p1x1
swap 1 // _ [p2x; 3] [p0x; 3] [dy; 3] [p0y; 3] [p1x; 3]
dup 11 dup 11 dup 11
// _ [p2x; 3] [p0x; 3] [dy; 3] [p0y; 3] [p1x; 3] [p0x; 3]
push -1
xb_mul // _ [p2x; 3] [p0x; 3] [dy; 3] [p0y; 3] [p1x; 3] [-p0x; 3]
xx_add // _ [p2x; 3] [p0x; 3] [dy; 3] [p0y; 3] [p1x - p0x; 3]
push -1
xb_mul // dx = p0x - p1x
// _ [p2x; 3] [p0x; 3] [dy; 3] [p0y; 3] [dx; 3]
swap 12 swap 1 swap 13 swap 2 swap 14 swap 2 swap 1
// _ [dx; 3] [p0x; 3] [dy; 3] [p0y; 3] [p2x; 3]
swap 3 swap 1 swap 4 swap 2 swap 5 swap 2 swap 1
// _ [dx; 3] [p0x; 3] [dy; 3] [p2x; 3] [p0y; 3]
swap 12 swap 1 swap 13 swap 2 swap 14 swap 2 swap 1
// _ [p0y; 3] [p0x; 3] [dy; 3] [p2x; 3] [dx; 3]
swap 9 swap 1 swap 10 swap 2 swap 11 swap 2 swap 1
// _ [p0y; 3] [dx; 3] [dy; 3] [p2x; 3] [p0x; 3]
push -1
xb_mul
xx_add // _ [p0y; 3] [dx; 3] [dy; 3] [p2x - p0x; 3]
xx_mul // a = (p2x - p0x) * dy
// _ [p0y; 3] [dx; 3] [a; 3]
swap 6 swap 1 swap 7 swap 2 swap 8 swap 2 swap 1
// _ [a; 3] [dx; 3] [p0y; 3]
dup 5 dup 5 dup 5
// _ [a; 3] [dx; 3] [p0y; 3] [dx; 3]
xx_mul // b = p0y * dx
// _ [a; 3] [dx; 3] [b; 3]
swap 3 swap 1 swap 4 swap 2 swap 5 swap 2 swap 1
// _ [a; 3] [b; 3] [dx; 3]
swap 6 swap 1 swap 7 swap 2 swap 8 swap 2 swap 1
// _ [dx; 3] [b; 3] [a; 3]
xx_add // c = a + b
// _ [dx; 3] [c; 3]
x_invert // _ [dx; 3] [1/c; 3]
xx_mul // _ [dx/c; 3]
x_invert // _ [c/dx; 3]
// _ [p2y; 3]
return
)
}
}
impl Closure for CollinearYXfe {
fn rust_shadow(&self, stack: &mut Vec<BFieldElement>) {
let mut pop_xfe = || {
let c_0 = stack.pop().unwrap();
let c_1 = stack.pop().unwrap();
let c_2 = stack.pop().unwrap();
XFieldElement::new([c_0, c_1, c_2])
};
let p0 = (pop_xfe(), pop_xfe());
let p1 = (pop_xfe(), pop_xfe());
let p2x = pop_xfe();
let p2y = Polynomial::get_colinear_y(p0, p1, p2x);
let [c_0, c_1, c_2] = p2y.coefficients;
stack.push(c_2);
stack.push(c_1);
stack.push(c_0);
}
fn pseudorandom_initial_state(
&self,
seed: [u8; 32],
_bench_case: Option<BenchmarkCase>,
) -> Vec<BFieldElement> {
const NUM_POINTS: usize = 2;
const NUM_COORDINATES: usize = 2 * NUM_POINTS + 1;
const NUM_ELEMENTS_PER_COORDINATE: usize = EXTENSION_DEGREE;
const NUM_ELEMENTS: usize = NUM_ELEMENTS_PER_COORDINATE * NUM_COORDINATES;
let mut rng: StdRng = SeedableRng::from_seed(seed);
let elements: [BFieldElement; NUM_ELEMENTS] = rng.gen();
[empty_stack(), elements.to_vec()].concat()
}
}
#[cfg(test)]
mod test {
use super::CollinearYXfe;
use crate::traits::closure::ShadowedClosure;
use crate::traits::rust_shadow::RustShadow;
#[test]
fn test() {
ShadowedClosure::new(CollinearYXfe).test()
}
}
#[cfg(test)]
mod bench {
use super::CollinearYXfe;
use crate::traits::closure::ShadowedClosure;
use crate::traits::rust_shadow::RustShadow;
#[test]
fn bench_colinear_y() {
ShadowedClosure::new(CollinearYXfe).bench();
}
}