mmtk/util/heap/
vmrequest.rs

1use super::layout::vm_layout::*;
2use crate::util::constants::*;
3use crate::util::Address;
4
5#[derive(Clone, Copy, Debug)]
6pub enum VMRequest {
7    Discontiguous,
8    Fixed { start: Address, extent: usize },
9    Extent { extent: usize, top: bool },
10    Fraction { frac: f32, top: bool },
11}
12
13impl VMRequest {
14    pub fn is_discontiguous(&self) -> bool {
15        matches!(self, VMRequest::Discontiguous)
16    }
17
18    pub fn common64bit(top: bool) -> Self {
19        VMRequest::Extent {
20            extent: vm_layout().max_space_extent(),
21            top,
22        }
23    }
24
25    pub fn discontiguous() -> Self {
26        if cfg!(target_pointer_width = "64") && vm_layout().force_use_contiguous_spaces {
27            return Self::common64bit(false);
28        }
29        VMRequest::Discontiguous
30    }
31
32    pub fn fixed_size(mb: usize) -> Self {
33        if cfg!(target_pointer_width = "64") && vm_layout().force_use_contiguous_spaces {
34            return Self::common64bit(false);
35        }
36        VMRequest::Extent {
37            extent: mb << LOG_BYTES_IN_MBYTE,
38            top: false,
39        }
40    }
41
42    pub fn fraction(frac: f32) -> Self {
43        if cfg!(target_pointer_width = "64") && vm_layout().force_use_contiguous_spaces {
44            return Self::common64bit(false);
45        }
46        VMRequest::Fraction { frac, top: false }
47    }
48
49    pub fn high_fixed_size(mb: usize) -> Self {
50        if cfg!(target_pointer_width = "64") && vm_layout().force_use_contiguous_spaces {
51            return Self::common64bit(true);
52        }
53        VMRequest::Extent {
54            extent: mb << LOG_BYTES_IN_MBYTE,
55            top: true,
56        }
57    }
58
59    pub fn fixed_extent(extent: usize, top: bool) -> Self {
60        if cfg!(target_pointer_width = "64") && vm_layout().force_use_contiguous_spaces {
61            return Self::common64bit(top);
62        }
63        VMRequest::Extent { extent, top }
64    }
65
66    pub fn fixed(start: Address, extent: usize) -> Self {
67        VMRequest::Fixed { start, extent }
68    }
69}
mmtk/util/heap/vmrequest.rs

mmtk/util/heap/
vmrequest.rs
