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Simplify and rename Stackmap::from_vec (#1032)

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Co-Authored-By: bjorn3 <bjorn3@users.noreply.github.com>
This commit is contained in:
AnthonyMikh
2019-09-18 11:11:32 +03:00
committed by Benjamin Bouvier
parent add6a4f269
commit c0274eca24
1 changed files with 25 additions and 24 deletions
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49
cranelift/codegen/src/binemit/stackmap.rs
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@@ -3,10 +3,13 @@ use crate::ir;
use crate::isa::TargetIsa; use crate::isa::TargetIsa;
use std::vec::Vec; use std::vec::Vec;
type Num = u32;
const NUM_BITS: usize = std::mem::size_of::<Num>() * 8;
/// Wrapper class for longer bit vectors that cannot be represented by a single BitSet. /// Wrapper class for longer bit vectors that cannot be represented by a single BitSet.
#[derive(Clone, Debug)] #[derive(Clone, Debug)]
pub struct Stackmap { pub struct Stackmap {
bitmap: Vec<BitSet<u32>>, bitmap: Vec<BitSet<Num>>,
} }
impl Stackmap { impl Stackmap {
@@ -52,34 +55,32 @@ impl Stackmap {
} }
} }
Stackmap::from_vec(&vec) Stackmap::from_slice(&vec)
} }
/// Create a vec of Bitsets from a vec of bools. /// Create a vec of Bitsets from a slice of bools.
pub fn from_vec(vec: &Vec<bool>) -> Self { pub fn from_slice(vec: &[bool]) -> Self {
let mut rem = vec.len(); let len = vec.len();
let num_word = ((rem as f32) / 32.0).ceil() as usize; let num_word = len / NUM_BITS + (len % NUM_BITS != 0) as usize;
let mut bitmap = Vec::with_capacity(num_word); let mut bitmap = Vec::with_capacity(num_word);
for i in 0..num_word { for segment in vec.chunks(NUM_BITS) {
let mut curr_word = 0; let mut curr_word = 0;
let count = if rem > 32 { 32 } else { rem }; for (i, set) in segment.iter().enumerate() {
for j in 0..count { if *set {
if vec[i * 32 + j] { curr_word |= 1 << i;
curr_word |= 1 << j;
} }
} }
bitmap.push(BitSet::<u32>(curr_word)); bitmap.push(BitSet(curr_word));
rem -= count;
} }
Self { bitmap } Self { bitmap }
} }
/// Returns a specified bit. /// Returns a specified bit.
pub fn get_bit(&self, bit_index: usize) -> bool { pub fn get_bit(&self, bit_index: usize) -> bool {
assert!(bit_index < 32 * self.bitmap.len()); assert!(bit_index < NUM_BITS * self.bitmap.len());
let word_index = bit_index / 32; let word_index = bit_index / NUM_BITS;
let word_offset = (bit_index % 32) as u8; let word_offset = (bit_index % NUM_BITS) as u8;
self.bitmap[word_index].contains(word_offset) self.bitmap[word_index].contains(word_offset)
} }
} }
@@ -91,26 +92,26 @@ mod tests {
#[test] #[test]
fn stackmaps() { fn stackmaps() {
let vec: Vec<bool> = Vec::new(); let vec: Vec<bool> = Vec::new();
assert!(Stackmap::from_vec(&vec).bitmap.is_empty()); assert!(Stackmap::from_slice(&vec).bitmap.is_empty());
let mut vec: [bool; 32] = Default::default(); let mut vec: [bool; NUM_BITS] = Default::default();
let set_true_idx = [5, 7, 24, 31]; let set_true_idx = [5, 7, 24, 31];
for idx in set_true_idx.iter() { for &idx in &set_true_idx {
vec[*idx] = true; vec[idx] = true;
} }
let mut vec = vec.to_vec(); let mut vec = vec.to_vec();
assert_eq!( assert_eq!(
vec![BitSet::<u32>(2164261024)], vec![BitSet::<Num>(2164261024)],
Stackmap::from_vec(&vec).bitmap Stackmap::from_slice(&vec).bitmap
); );
vec.push(false); vec.push(false);
vec.push(true); vec.push(true);
let res = Stackmap::from_vec(&vec); let res = Stackmap::from_slice(&vec);
assert_eq!( assert_eq!(
vec![BitSet::<u32>(2164261024), BitSet::<u32>(2)], vec![BitSet::<Num>(2164261024), BitSet::<Num>(2)],
res.bitmap res.bitmap
); );