weirflow 0.1.0

GPU-first dataflow analysis primitives for Vyre and Santh compiler pipelines.
Documentation 
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//! `post_dominates`  -  query the post-dominator tree.
//!
//! Per node `n` and target `t`, write 1 iff `n` post-dominates `t`
//! (every path from `t` to function exit goes through `n`). This is
//! the dual of dominance and is needed for control-dependence
//! analysis + the `csrf_missing_token` rule's path checks.

use vyre::ir::Program;
use vyre_primitives::bitset::and::bitset_and;
use vyre_primitives::graph::csr_forward_traverse::bitset_words;

pub(crate) const OP_ID: &str = "weir::post_dominates";

/// Build a post-dominator query Program.
///
/// Inputs:
/// - `pdom_set`: per-node bitset where bit `m` is set in node `n`'s
///   row iff `n` post-dominates `m` (host-supplied via
///   classical post-dominator construction).
/// - `target_set`: per-node bitset of target nodes being queried.
/// - `out`:        per-node bitset; bit `n` set iff `n` post-
///   dominates SOME target in `target_set`.
#[must_use]
pub fn post_dominates(node_count: u32, pdom_set: &str, target_set: &str, out: &str) -> Program {
    let words = bitset_words(node_count);
    vyre_harness::region::tag_program(OP_ID, bitset_and(pdom_set, target_set, out, words))
}

/// reference oracle.
#[must_use]
#[cfg(any(test, feature = "cpu-parity"))]
#[deprecated(
    note = "reference oracle only; production code must dispatch the Weir Program on a concrete GPU backend or use weir::oracle for parity evidence"
)]
pub(crate) fn cpu_ref(pdom_set: &[u32], target_set: &[u32]) -> Vec<u32> {
    vyre_primitives::bitset::and::cpu_ref(pdom_set, target_set)
}

/// Soundness marker for [`post_dominates`].
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub struct PostDominates;
impl super::soundness::SoundnessTagged for PostDominates {
    fn soundness(&self) -> super::soundness::Soundness {
        super::soundness::Soundness::Exact
    }
}

inventory::submit! {
    vyre_harness::OpEntry::new(
        OP_ID,
        || post_dominates(4, "pdom", "target", "out"),
        Some(|| {
            let u32s = crate::dispatch_decode::pack_u32;
            vec![vec![u32s(&[0b1111]), u32s(&[0b0011]), u32s(&[0])]]
        }),
        Some(|| {
            let u32s = crate::dispatch_decode::pack_u32;
            vec![vec![u32s(&[0b0011])]]
        }),
    )
}

#[cfg(test)]
#[allow(deprecated)]
mod tests {
    use super::*;

    #[test]
    fn pdom_intersect_target_set() {
        assert_eq!(cpu_ref(&[0b1111], &[0b0011]), vec![0b0011]);
    }

    #[test]
    fn no_pdom_returns_empty() {
        assert_eq!(cpu_ref(&[0], &[0xFFFF]), vec![0]);
    }

    #[test]
    fn empty_target_returns_empty() {
        assert_eq!(cpu_ref(&[0xFFFF], &[0]), vec![0]);
    }

    #[test]
    fn partial_overlap() {
        assert_eq!(cpu_ref(&[0xFF00], &[0x0FF0]), vec![0x0F00]);
    }
}