weirflow 0.1.0

GPU-first dataflow analysis primitives for Vyre and Santh compiler pipelines.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89

//! `reaching_def`  -  reaching-definitions query packed as a bitset.
//!
//! Per use site `u`, return the set of definitions that reach `u`
//! (i.e. there's a CFG path from def to use with no intervening def
//! of the same variable). This is the bitset dataflow consumers read for
//! the `uses_of($def)` predicate's complement direction.

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::reaching_def";

/// Build a reaching-def query Program.
///
/// Inputs:
/// - `gen_kill_in`: per-node bitset of definitions reaching the
///   entry of each node (host-supplied via classical
///   reaching-defs analysis).
/// - `use_set`:     per-node bitset of use sites being queried.
/// - `out`:         per-node bitset; bit `n` set iff `n` is a use
///   AND has a reaching def.
#[must_use]
pub fn reaching_def(node_count: u32, gen_kill_in: &str, use_set: &str, out: &str) -> Program {
    let words = bitset_words(node_count);
    vyre_harness::region::tag_program(OP_ID, bitset_and(gen_kill_in, use_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(gen_kill_in: &[u32], use_set: &[u32]) -> Vec<u32> {
    vyre_primitives::bitset::and::cpu_ref(gen_kill_in, use_set)
}

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

inventory::submit! {
    vyre_harness::OpEntry::new(
        OP_ID,
        || reaching_def(4, "reaching", "uses", "out"),
        Some(|| {
            let u32s = crate::dispatch_decode::pack_u32;
            vec![vec![u32s(&[0b1111]), u32s(&[0b0010]), u32s(&[0])]]
        }),
        Some(|| {
            let u32s = crate::dispatch_decode::pack_u32;
            vec![vec![u32s(&[0b0010])]]
        }),
    )
}

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

    #[test]
    fn use_with_reaching_def_returns_one() {
        assert_eq!(cpu_ref(&[0b1111], &[0b0010]), vec![0b0010]);
    }

    #[test]
    fn use_without_reaching_def_returns_zero() {
        assert_eq!(cpu_ref(&[0b0001], &[0b0010]), vec![0]);
    }

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

    #[test]
    fn idempotent_intersection() {
        let a = cpu_ref(&[0xF0F0], &[0x0FF0]);
        let b = cpu_ref(&[0xF0F0], &[0x0FF0]);
        assert_eq!(a, b);
    }
}