Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 301 insertions, 0 deletions

diff --git a/vendor/ena/src/bitvec.rs b/vendor/ena/src/bitvec.rs
new file mode 100644
index 000000000..3677c8c5e
--- /dev/null
+++ b/vendor/ena/src/bitvec.rs
@@ -0,0 +1,301 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+/// A very simple BitVector type.
+pub struct BitVector {
+    data: Vec<u64>,
+}
+
+impl BitVector {
+    pub fn new(num_bits: usize) -> BitVector {
+        let num_words = u64s(num_bits);
+        BitVector { data: vec![0; num_words] }
+    }
+
+    pub fn contains(&self, bit: usize) -> bool {
+        let (word, mask) = word_mask(bit);
+        (self.data[word] & mask) != 0
+    }
+
+    /// Returns true if the bit has changed.
+    pub fn insert(&mut self, bit: usize) -> bool {
+        let (word, mask) = word_mask(bit);
+        let data = &mut self.data[word];
+        let value = *data;
+        let new_value = value | mask;
+        *data = new_value;
+        new_value != value
+    }
+
+    pub fn insert_all(&mut self, all: &BitVector) -> bool {
+        assert!(self.data.len() == all.data.len());
+        let mut changed = false;
+        for (i, j) in self.data.iter_mut().zip(&all.data) {
+            let value = *i;
+            *i = value | *j;
+            if value != *i {
+                changed = true;
+            }
+        }
+        changed
+    }
+
+    pub fn grow(&mut self, num_bits: usize) {
+        let num_words = u64s(num_bits);
+        let extra_words = self.data.len() - num_words;
+        self.data.extend((0..extra_words).map(|_| 0));
+    }
+
+    /// Iterates over indexes of set bits in a sorted order
+    pub fn iter<'a>(&'a self) -> BitVectorIter<'a> {
+        BitVectorIter {
+            iter: self.data.iter(),
+            current: 0,
+            idx: 0,
+        }
+    }
+}
+
+pub struct BitVectorIter<'a> {
+    iter: ::std::slice::Iter<'a, u64>,
+    current: u64,
+    idx: usize,
+}
+
+impl<'a> Iterator for BitVectorIter<'a> {
+    type Item = usize;
+    fn next(&mut self) -> Option<usize> {
+        while self.current == 0 {
+            self.current = if let Some(&i) = self.iter.next() {
+                if i == 0 {
+                    self.idx += 64;
+                    continue;
+                } else {
+                    self.idx = u64s(self.idx) * 64;
+                    i
+                }
+            } else {
+                return None;
+            }
+        }
+        let offset = self.current.trailing_zeros() as usize;
+        self.current >>= offset;
+        self.current >>= 1; // shift otherwise overflows for 0b1000_0000_…_0000
+        self.idx += offset + 1;
+        return Some(self.idx - 1);
+    }
+}
+
+/// A "bit matrix" is basically a square matrix of booleans
+/// represented as one gigantic bitvector. In other words, it is as if
+/// you have N bitvectors, each of length N. Note that `elements` here is `N`/
+#[derive(Clone)]
+pub struct BitMatrix {
+    elements: usize,
+    vector: Vec<u64>,
+}
+
+impl BitMatrix {
+    // Create a new `elements x elements` matrix, initially empty.
+    pub fn new(elements: usize) -> BitMatrix {
+        // For every element, we need one bit for every other
+        // element. Round up to an even number of u64s.
+        let u64s_per_elem = u64s(elements);
+        BitMatrix {
+            elements: elements,
+            vector: vec![0; elements * u64s_per_elem],
+        }
+    }
+
+    /// The range of bits for a given element.
+    fn range(&self, element: usize) -> (usize, usize) {
+        let u64s_per_elem = u64s(self.elements);
+        let start = element * u64s_per_elem;
+        (start, start + u64s_per_elem)
+    }
+
+    pub fn add(&mut self, source: usize, target: usize) -> bool {
+        let (start, _) = self.range(source);
+        let (word, mask) = word_mask(target);
+        let mut vector = &mut self.vector[..];
+        let v1 = vector[start + word];
+        let v2 = v1 | mask;
+        vector[start + word] = v2;
+        v1 != v2
+    }
+
+    /// Do the bits from `source` contain `target`?
+    ///
+    /// Put another way, if the matrix represents (transitive)
+    /// reachability, can `source` reach `target`?
+    pub fn contains(&self, source: usize, target: usize) -> bool {
+        let (start, _) = self.range(source);
+        let (word, mask) = word_mask(target);
+        (self.vector[start + word] & mask) != 0
+    }
+
+    /// Returns those indices that are reachable from both `a` and
+    /// `b`. This is an O(n) operation where `n` is the number of
+    /// elements (somewhat independent from the actual size of the
+    /// intersection, in particular).
+    pub fn intersection(&self, a: usize, b: usize) -> Vec<usize> {
+        let (a_start, a_end) = self.range(a);
+        let (b_start, b_end) = self.range(b);
+        let mut result = Vec::with_capacity(self.elements);
+        for (base, (i, j)) in (a_start..a_end).zip(b_start..b_end).enumerate() {
+            let mut v = self.vector[i] & self.vector[j];
+            for bit in 0..64 {
+                if v == 0 {
+                    break;
+                }
+                if v & 0x1 != 0 {
+                    result.push(base * 64 + bit);
+                }
+                v >>= 1;
+            }
+        }
+        result
+    }
+
+    /// Add the bits from `read` to the bits from `write`,
+    /// return true if anything changed.
+    ///
+    /// This is used when computing transitive reachability because if
+    /// you have an edge `write -> read`, because in that case
+    /// `write` can reach everything that `read` can (and
+    /// potentially more).
+    pub fn merge(&mut self, read: usize, write: usize) -> bool {
+        let (read_start, read_end) = self.range(read);
+        let (write_start, write_end) = self.range(write);
+        let vector = &mut self.vector[..];
+        let mut changed = false;
+        for (read_index, write_index) in (read_start..read_end).zip(write_start..write_end) {
+            let v1 = vector[write_index];
+            let v2 = v1 | vector[read_index];
+            vector[write_index] = v2;
+            changed = changed | (v1 != v2);
+        }
+        changed
+    }
+}
+
+fn u64s(elements: usize) -> usize {
+    (elements + 63) / 64
+}
+
+fn word_mask(index: usize) -> (usize, u64) {
+    let word = index / 64;
+    let mask = 1 << (index % 64);
+    (word, mask)
+}
+
+#[test]
+fn bitvec_iter_works() {
+    let mut bitvec = BitVector::new(100);
+    bitvec.insert(1);
+    bitvec.insert(10);
+    bitvec.insert(19);
+    bitvec.insert(62);
+    bitvec.insert(63);
+    bitvec.insert(64);
+    bitvec.insert(65);
+    bitvec.insert(66);
+    bitvec.insert(99);
+    assert_eq!(bitvec.iter().collect::<Vec<_>>(),
+               [1, 10, 19, 62, 63, 64, 65, 66, 99]);
+}
+
+#[test]
+fn bitvec_iter_works_2() {
+    let mut bitvec = BitVector::new(300);
+    bitvec.insert(1);
+    bitvec.insert(10);
+    bitvec.insert(19);
+    bitvec.insert(62);
+    bitvec.insert(66);
+    bitvec.insert(99);
+    bitvec.insert(299);
+    assert_eq!(bitvec.iter().collect::<Vec<_>>(),
+               [1, 10, 19, 62, 66, 99, 299]);
+
+}
+
+#[test]
+fn bitvec_iter_works_3() {
+    let mut bitvec = BitVector::new(319);
+    bitvec.insert(0);
+    bitvec.insert(127);
+    bitvec.insert(191);
+    bitvec.insert(255);
+    bitvec.insert(319);
+    assert_eq!(bitvec.iter().collect::<Vec<_>>(), [0, 127, 191, 255, 319]);
+}
+
+#[test]
+fn union_two_vecs() {
+    let mut vec1 = BitVector::new(65);
+    let mut vec2 = BitVector::new(65);
+    assert!(vec1.insert(3));
+    assert!(!vec1.insert(3));
+    assert!(vec2.insert(5));
+    assert!(vec2.insert(64));
+    assert!(vec1.insert_all(&vec2));
+    assert!(!vec1.insert_all(&vec2));
+    assert!(vec1.contains(3));
+    assert!(!vec1.contains(4));
+    assert!(vec1.contains(5));
+    assert!(!vec1.contains(63));
+    assert!(vec1.contains(64));
+}
+
+#[test]
+fn grow() {
+    let mut vec1 = BitVector::new(65);
+    assert!(vec1.insert(3));
+    assert!(!vec1.insert(3));
+    assert!(vec1.insert(5));
+    assert!(vec1.insert(64));
+    vec1.grow(128);
+    assert!(vec1.contains(3));
+    assert!(vec1.contains(5));
+    assert!(vec1.contains(64));
+    assert!(!vec1.contains(126));
+}
+
+#[test]
+fn matrix_intersection() {
+    let mut vec1 = BitMatrix::new(200);
+
+    // (*) Elements reachable from both 2 and 65.
+
+    vec1.add(2, 3);
+    vec1.add(2, 6);
+    vec1.add(2, 10); // (*)
+    vec1.add(2, 64); // (*)
+    vec1.add(2, 65);
+    vec1.add(2, 130);
+    vec1.add(2, 160); // (*)
+
+    vec1.add(64, 133);
+
+    vec1.add(65, 2);
+    vec1.add(65, 8);
+    vec1.add(65, 10); // (*)
+    vec1.add(65, 64); // (*)
+    vec1.add(65, 68);
+    vec1.add(65, 133);
+    vec1.add(65, 160); // (*)
+
+    let intersection = vec1.intersection(2, 64);
+    assert!(intersection.is_empty());
+
+    let intersection = vec1.intersection(2, 65);
+    assert_eq!(intersection, &[10, 64, 160]);
+}