Struct rustc_index::bit_set::BitMatrix [−][src]
pub struct BitMatrix<R: Idx, C: Idx> {
num_rows: usize,
num_columns: usize,
words: Vec<Word>,
marker: PhantomData<(R, C)>,
}
Expand description
A fixed-size 2D bit matrix type with a dense representation.
R
and C
are index types used to identify rows and columns respectively;
typically newtyped usize
wrappers, but they can also just be usize
.
All operations that involve a row and/or column index will panic if the index exceeds the relevant bound.
Fields
num_rows: usize
num_columns: usize
words: Vec<Word>
marker: PhantomData<(R, C)>
Implementations
Creates a new rows x columns
matrix, initially empty.
Creates a new matrix, with row
used as the value for every row.
Sets the cell at (row, column)
to true. Put another way, insert
column
to the bitset for row
.
Returns true
if this changed the matrix.
Do the bits from row
contain column
? Put another way, is
the matrix cell at (row, column)
true? Put yet another way,
if the matrix represents (transitive) reachability, can
row
reach column
?
Returns those indices that are true in rows 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).
Adds the bits from row read
to the bits from row write
, and
returns 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).
Adds the bits from with
to the bits from row write
, and
returns true
if anything changed.
Sets every cell in row
to true.
Clear excess bits in the final word of the row.
Iterates through all the columns set to true in a given row of the matrix.
Trait Implementations
Auto Trait Implementations
impl<R, C> RefUnwindSafe for BitMatrix<R, C> where
C: RefUnwindSafe,
R: RefUnwindSafe,
impl<R, C> UnwindSafe for BitMatrix<R, C> where
C: UnwindSafe,
R: UnwindSafe,
Blanket Implementations
Mutably borrows from an owned value. Read more
Layout
Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...)
attributes. Please see the Rust Reference’s “Type Layout” chapter for details on type layout guarantees.
Size: 40 bytes