2016-03-05 00:52:14 -06:00
|
|
|
use byteorder::{self, ByteOrder};
|
2016-03-05 00:48:23 -06:00
|
|
|
use rustc::middle::ty;
|
|
|
|
use std::collections::HashMap;
|
|
|
|
use std::mem;
|
|
|
|
use std::ptr;
|
|
|
|
|
|
|
|
use interpreter::{EvalError, EvalResult};
|
|
|
|
|
|
|
|
pub struct Memory {
|
|
|
|
next_id: u64,
|
|
|
|
alloc_map: HashMap<u64, Allocation>,
|
|
|
|
}
|
|
|
|
|
|
|
|
#[derive(Copy, Clone, Debug, Eq, PartialEq)]
|
|
|
|
pub struct AllocId(u64);
|
|
|
|
|
2016-03-05 00:50:53 -06:00
|
|
|
#[derive(Debug)]
|
2016-03-05 00:48:23 -06:00
|
|
|
pub struct Allocation {
|
|
|
|
pub bytes: Vec<u8>,
|
|
|
|
// TODO(tsion): relocations
|
|
|
|
// TODO(tsion): undef mask
|
|
|
|
}
|
|
|
|
|
2016-03-07 07:10:52 -06:00
|
|
|
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
|
2016-03-05 00:48:23 -06:00
|
|
|
pub struct Pointer {
|
|
|
|
pub alloc_id: AllocId,
|
|
|
|
pub offset: usize,
|
|
|
|
}
|
|
|
|
|
|
|
|
#[derive(Clone, Debug, PartialEq, Eq)]
|
|
|
|
pub struct FieldRepr {
|
|
|
|
pub offset: usize,
|
|
|
|
pub repr: Repr,
|
|
|
|
}
|
|
|
|
|
|
|
|
#[derive(Clone, Debug, PartialEq, Eq)]
|
|
|
|
pub enum Repr {
|
2016-03-07 04:44:03 -06:00
|
|
|
Bool,
|
2016-03-05 00:48:23 -06:00
|
|
|
Int,
|
|
|
|
Aggregate {
|
|
|
|
size: usize,
|
|
|
|
fields: Vec<FieldRepr>,
|
|
|
|
},
|
|
|
|
}
|
|
|
|
|
|
|
|
impl Memory {
|
|
|
|
pub fn new() -> Self {
|
|
|
|
Memory { next_id: 0, alloc_map: HashMap::new() }
|
|
|
|
}
|
|
|
|
|
|
|
|
pub fn allocate_raw(&mut self, size: usize) -> AllocId {
|
|
|
|
let id = AllocId(self.next_id);
|
|
|
|
let alloc = Allocation { bytes: vec![0; size] };
|
|
|
|
self.alloc_map.insert(self.next_id, alloc);
|
|
|
|
self.next_id += 1;
|
|
|
|
id
|
|
|
|
}
|
|
|
|
|
2016-03-07 07:10:52 -06:00
|
|
|
pub fn allocate(&mut self, repr: &Repr) -> Pointer {
|
2016-03-05 00:48:23 -06:00
|
|
|
Pointer {
|
|
|
|
alloc_id: self.allocate_raw(repr.size()),
|
|
|
|
offset: 0,
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
pub fn get(&self, id: AllocId) -> EvalResult<&Allocation> {
|
|
|
|
self.alloc_map.get(&id.0).ok_or(EvalError::DanglingPointerDeref)
|
|
|
|
}
|
|
|
|
|
|
|
|
pub fn get_mut(&mut self, id: AllocId) -> EvalResult<&mut Allocation> {
|
|
|
|
self.alloc_map.get_mut(&id.0).ok_or(EvalError::DanglingPointerDeref)
|
|
|
|
}
|
|
|
|
|
2016-03-07 07:10:52 -06:00
|
|
|
fn get_bytes(&self, ptr: Pointer, size: usize) -> EvalResult<&[u8]> {
|
2016-03-05 00:48:23 -06:00
|
|
|
let alloc = try!(self.get(ptr.alloc_id));
|
|
|
|
try!(alloc.check_bytes(ptr.offset, ptr.offset + size));
|
|
|
|
Ok(&alloc.bytes[ptr.offset..ptr.offset + size])
|
|
|
|
}
|
|
|
|
|
2016-03-07 07:10:52 -06:00
|
|
|
fn get_bytes_mut(&mut self, ptr: Pointer, size: usize) -> EvalResult<&mut [u8]> {
|
2016-03-05 00:48:23 -06:00
|
|
|
let alloc = try!(self.get_mut(ptr.alloc_id));
|
|
|
|
try!(alloc.check_bytes(ptr.offset, ptr.offset + size));
|
|
|
|
Ok(&mut alloc.bytes[ptr.offset..ptr.offset + size])
|
|
|
|
}
|
|
|
|
|
2016-03-07 07:10:52 -06:00
|
|
|
pub fn copy(&mut self, src: Pointer, dest: Pointer, size: usize) -> EvalResult<()> {
|
2016-03-05 00:48:23 -06:00
|
|
|
let src_bytes = try!(self.get_bytes_mut(src, size)).as_mut_ptr();
|
|
|
|
let dest_bytes = try!(self.get_bytes_mut(dest, size)).as_mut_ptr();
|
|
|
|
|
|
|
|
// SAFE: The above indexing would have panicked if there weren't at least `size` bytes
|
|
|
|
// behind `src` and `dest`. Also, we use the overlapping-safe `ptr::copy` if `src` and
|
|
|
|
// `dest` could possibly overlap.
|
|
|
|
unsafe {
|
|
|
|
if src.alloc_id == dest.alloc_id {
|
|
|
|
ptr::copy(src_bytes, dest_bytes, size);
|
|
|
|
} else {
|
|
|
|
ptr::copy_nonoverlapping(src_bytes, dest_bytes, size);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
Ok(())
|
|
|
|
}
|
|
|
|
|
2016-03-07 07:10:52 -06:00
|
|
|
pub fn read_int(&self, ptr: Pointer) -> EvalResult<i64> {
|
2016-03-07 04:44:03 -06:00
|
|
|
self.get_bytes(ptr, Repr::Int.size()).map(byteorder::NativeEndian::read_i64)
|
2016-03-05 00:48:23 -06:00
|
|
|
}
|
|
|
|
|
2016-03-07 07:10:52 -06:00
|
|
|
pub fn write_int(&mut self, ptr: Pointer, n: i64) -> EvalResult<()> {
|
2016-03-05 00:48:23 -06:00
|
|
|
let bytes = try!(self.get_bytes_mut(ptr, Repr::Int.size()));
|
2016-03-07 04:44:03 -06:00
|
|
|
byteorder::NativeEndian::write_i64(bytes, n);
|
|
|
|
Ok(())
|
|
|
|
}
|
|
|
|
|
2016-03-07 07:10:52 -06:00
|
|
|
pub fn read_bool(&self, ptr: Pointer) -> EvalResult<bool> {
|
2016-03-07 04:44:03 -06:00
|
|
|
let bytes = try!(self.get_bytes(ptr, 1));
|
|
|
|
match bytes[0] {
|
|
|
|
0 => Ok(false),
|
|
|
|
1 => Ok(true),
|
|
|
|
_ => Err(EvalError::InvalidBool),
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2016-03-07 07:10:52 -06:00
|
|
|
pub fn write_bool(&mut self, ptr: Pointer, b: bool) -> EvalResult<()> {
|
2016-03-07 04:44:03 -06:00
|
|
|
let bytes = try!(self.get_bytes_mut(ptr, 1));
|
|
|
|
bytes[0] = b as u8;
|
|
|
|
Ok(())
|
2016-03-05 00:48:23 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
impl Allocation {
|
|
|
|
fn check_bytes(&self, start: usize, end: usize) -> EvalResult<()> {
|
2016-03-07 04:44:03 -06:00
|
|
|
if start < self.bytes.len() && end <= self.bytes.len() {
|
|
|
|
Ok(())
|
|
|
|
} else {
|
|
|
|
Err(EvalError::PointerOutOfBounds)
|
2016-03-05 00:48:23 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
impl Pointer {
|
2016-03-07 07:10:52 -06:00
|
|
|
pub fn offset(self, i: usize) -> Self {
|
|
|
|
// TODO(tsion): Check for offset out of bounds.
|
|
|
|
Pointer { offset: self.offset + i, ..self }
|
2016-03-05 00:48:23 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
impl Repr {
|
|
|
|
// TODO(tsion): Cache these outputs.
|
|
|
|
pub fn from_ty(ty: ty::Ty) -> Self {
|
|
|
|
match ty.sty {
|
2016-03-07 04:44:03 -06:00
|
|
|
ty::TyBool => Repr::Bool,
|
|
|
|
|
2016-03-05 00:48:23 -06:00
|
|
|
ty::TyInt(_) => Repr::Int,
|
|
|
|
|
|
|
|
ty::TyTuple(ref fields) => {
|
|
|
|
let mut size = 0;
|
|
|
|
let fields = fields.iter().map(|ty| {
|
|
|
|
let repr = Repr::from_ty(ty);
|
|
|
|
let old_size = size;
|
|
|
|
size += repr.size();
|
|
|
|
FieldRepr { offset: old_size, repr: repr }
|
|
|
|
}).collect();
|
|
|
|
Repr::Aggregate { size: size, fields: fields }
|
|
|
|
},
|
|
|
|
|
|
|
|
_ => unimplemented!(),
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
pub fn size(&self) -> usize {
|
|
|
|
match *self {
|
2016-03-07 04:44:03 -06:00
|
|
|
Repr::Bool => 1,
|
2016-03-05 00:48:23 -06:00
|
|
|
Repr::Int => mem::size_of::<i64>(),
|
|
|
|
Repr::Aggregate { size, .. } => size,
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|