2020-03-16 18:48:44 -05:00
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//! Implements threads.
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use std::cell::RefCell;
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2020-04-07 22:20:41 -05:00
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use std::convert::TryFrom;
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2020-04-15 23:25:12 -05:00
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use std::num::NonZeroU32;
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2020-03-16 18:48:44 -05:00
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use log::trace;
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use rustc_data_structures::fx::FxHashMap;
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2020-04-16 15:32:40 -05:00
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use rustc_hir::def_id::DefId;
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2020-03-16 18:48:44 -05:00
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use rustc_index::vec::{Idx, IndexVec};
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2020-04-16 15:32:40 -05:00
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use rustc_middle::{
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middle::codegen_fn_attrs::CodegenFnAttrFlags,
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mir,
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ty::{self, Instance},
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};
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2020-03-16 18:48:44 -05:00
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use crate::*;
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2020-04-16 21:40:02 -05:00
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#[derive(Clone, Copy, Debug, PartialEq, Eq)]
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pub enum SchedulingAction {
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/// Execute step on the active thread.
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ExecuteStep,
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/// Execute destructors of the active thread.
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ExecuteDtors,
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/// Stop the program.
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Stop,
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}
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2020-03-16 18:48:44 -05:00
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/// A thread identifier.
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#[derive(Clone, Copy, Debug, PartialOrd, Ord, PartialEq, Eq, Hash)]
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pub struct ThreadId(usize);
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2020-04-19 16:21:18 -05:00
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/// The main thread. When it terminates, the whole application terminates.
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const MAIN_THREAD: ThreadId = ThreadId(0);
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2020-03-16 18:48:44 -05:00
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impl Idx for ThreadId {
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fn new(idx: usize) -> Self {
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ThreadId(idx)
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}
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fn index(self) -> usize {
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self.0
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}
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}
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impl From<u64> for ThreadId {
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fn from(id: u64) -> Self {
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Self(usize::try_from(id).unwrap())
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2020-03-16 18:48:44 -05:00
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}
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}
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2020-04-07 22:20:41 -05:00
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impl From<u32> for ThreadId {
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fn from(id: u32) -> Self {
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Self(usize::try_from(id).unwrap())
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2020-04-07 22:20:41 -05:00
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}
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}
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impl ThreadId {
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pub fn to_u32_scalar<'tcx>(&self) -> Scalar<Tag> {
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Scalar::from_u32(u32::try_from(self.0).unwrap())
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}
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}
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2020-04-26 16:42:07 -05:00
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/// An identifier of a set of blocked threads. 0 is used to indicate the absence
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/// of a blockset identifier and, therefore, is not a valid identifier.
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2020-04-07 22:20:41 -05:00
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#[derive(Clone, Copy, Debug, PartialOrd, Ord, PartialEq, Eq, Hash)]
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pub struct BlockSetId(NonZeroU32);
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impl From<u32> for BlockSetId {
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fn from(id: u32) -> Self {
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Self(NonZeroU32::new(id).expect("0 is not a valid blockset id"))
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2020-04-07 22:20:41 -05:00
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}
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}
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impl BlockSetId {
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pub fn to_u32_scalar<'tcx>(&self) -> Scalar<Tag> {
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Scalar::from_u32(self.0.get())
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2020-04-07 22:20:41 -05:00
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}
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}
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2020-03-16 18:48:44 -05:00
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/// The state of a thread.
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#[derive(Debug, Copy, Clone, PartialEq, Eq)]
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pub enum ThreadState {
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/// The thread is enabled and can be executed.
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Enabled,
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/// The thread tried to join the specified thread and is blocked until that
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/// thread terminates.
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BlockedOnJoin(ThreadId),
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/// The thread is blocked and belongs to the given blockset.
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Blocked(BlockSetId),
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/// The thread has terminated its execution (we do not delete terminated
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/// threads).
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Terminated,
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}
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2020-04-19 18:43:40 -05:00
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/// The join status of a thread.
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#[derive(Debug, Copy, Clone, PartialEq, Eq)]
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enum ThreadJoinStatus {
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/// The thread can be joined.
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Joinable,
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/// A thread is detached if its join handle was destroyed and no other
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/// thread can join it.
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Detached,
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/// The thread was already joined by some thread and cannot be joined again.
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Joined,
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}
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2020-03-16 18:48:44 -05:00
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/// A thread.
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pub struct Thread<'mir, 'tcx> {
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state: ThreadState,
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/// Name of the thread.
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thread_name: Option<Vec<u8>>,
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2020-03-16 18:48:44 -05:00
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/// The virtual call stack.
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stack: Vec<Frame<'mir, 'tcx, Tag, FrameData<'tcx>>>,
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2020-04-19 18:43:40 -05:00
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/// The join status.
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join_status: ThreadJoinStatus,
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2020-03-16 18:48:44 -05:00
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}
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impl<'mir, 'tcx> Thread<'mir, 'tcx> {
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2020-04-26 16:42:07 -05:00
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/// Check if the thread is done executing (no more stack frames). If yes,
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/// change the state to terminated and return `true`.
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2020-03-16 18:48:44 -05:00
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fn check_terminated(&mut self) -> bool {
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if self.state == ThreadState::Enabled {
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if self.stack.is_empty() {
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self.state = ThreadState::Terminated;
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return true;
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}
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}
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false
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}
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}
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impl<'mir, 'tcx> std::fmt::Debug for Thread<'mir, 'tcx> {
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fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
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2020-04-19 23:21:22 -05:00
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if let Some(ref name) = self.thread_name {
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write!(f, "{}", String::from_utf8_lossy(name))?;
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2020-04-19 23:21:22 -05:00
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} else {
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write!(f, "<unnamed>")?;
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2020-04-19 23:21:22 -05:00
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}
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write!(f, "({:?}, {:?})", self.state, self.join_status)
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2020-03-16 18:48:44 -05:00
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}
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}
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impl<'mir, 'tcx> Default for Thread<'mir, 'tcx> {
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fn default() -> Self {
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2020-04-19 18:43:40 -05:00
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Self {
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state: ThreadState::Enabled,
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thread_name: None,
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stack: Vec::new(),
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join_status: ThreadJoinStatus::Joinable,
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}
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2020-03-16 18:48:44 -05:00
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}
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}
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/// A set of threads.
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#[derive(Debug)]
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2020-04-09 14:06:33 -05:00
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pub struct ThreadManager<'mir, 'tcx> {
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/// Identifier of the currently active thread.
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active_thread: ThreadId,
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/// Threads used in the program.
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///
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/// Note that this vector also contains terminated threads.
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threads: IndexVec<ThreadId, Thread<'mir, 'tcx>>,
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/// A counter used to generate unique identifiers for blocksets.
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blockset_counter: u32,
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2020-04-16 15:32:40 -05:00
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/// A mapping from a thread-local static to an allocation id of a thread
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/// specific allocation.
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thread_local_alloc_ids: RefCell<FxHashMap<(DefId, ThreadId), AllocId>>,
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2020-04-18 17:39:53 -05:00
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/// A flag that indicates that we should change the active thread.
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yield_active_thread: bool,
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}
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2020-04-09 14:06:33 -05:00
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impl<'mir, 'tcx> Default for ThreadManager<'mir, 'tcx> {
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fn default() -> Self {
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let mut threads = IndexVec::new();
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// Create the main thread and add it to the list of threads.
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2020-04-20 15:22:28 -05:00
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let mut main_thread = Thread::default();
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2020-04-26 16:42:07 -05:00
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// The main thread can *not* be joined on.
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main_thread.join_status = ThreadJoinStatus::Detached;
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threads.push(main_thread);
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2020-04-15 16:34:34 -05:00
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Self {
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active_thread: ThreadId::new(0),
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threads: threads,
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blockset_counter: 0,
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thread_local_alloc_ids: Default::default(),
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2020-04-18 17:39:53 -05:00
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yield_active_thread: false,
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}
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2020-03-16 18:48:44 -05:00
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}
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}
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2020-04-09 14:06:33 -05:00
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impl<'mir, 'tcx: 'mir> ThreadManager<'mir, 'tcx> {
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2020-04-15 16:34:34 -05:00
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/// Check if we have an allocation for the given thread local static for the
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/// active thread.
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2020-04-18 14:25:11 -05:00
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fn get_thread_local_alloc_id(&self, def_id: DefId) -> Option<AllocId> {
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self.thread_local_alloc_ids.borrow().get(&(def_id, self.active_thread)).cloned()
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}
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2020-04-15 16:34:34 -05:00
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/// Set the allocation id as the allocation id of the given thread local
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/// static for the active thread.
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2020-04-19 16:21:18 -05:00
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///
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/// Panics if a thread local is initialized twice for the same thread.
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2020-04-18 14:25:11 -05:00
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fn set_thread_local_alloc_id(&self, def_id: DefId, new_alloc_id: AllocId) {
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self.thread_local_alloc_ids
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.borrow_mut()
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.insert((def_id, self.active_thread), new_alloc_id)
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.unwrap_none();
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2020-04-15 16:34:34 -05:00
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}
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2020-04-15 23:25:12 -05:00
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2020-03-16 18:48:44 -05:00
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/// Borrow the stack of the active thread.
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fn active_thread_stack(&self) -> &[Frame<'mir, 'tcx, Tag, FrameData<'tcx>>] {
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&self.threads[self.active_thread].stack
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}
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2020-04-15 23:25:12 -05:00
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2020-03-16 18:48:44 -05:00
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/// Mutably borrow the stack of the active thread.
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fn active_thread_stack_mut(&mut self) -> &mut Vec<Frame<'mir, 'tcx, Tag, FrameData<'tcx>>> {
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&mut self.threads[self.active_thread].stack
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}
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2020-04-15 23:25:12 -05:00
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2020-03-16 18:48:44 -05:00
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/// Create a new thread and returns its id.
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fn create_thread(&mut self) -> ThreadId {
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let new_thread_id = ThreadId::new(self.threads.len());
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self.threads.push(Default::default());
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new_thread_id
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}
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2020-03-16 18:48:44 -05:00
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/// Set an active thread and return the id of the thread that was active before.
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2020-04-06 18:12:13 -05:00
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fn set_active_thread_id(&mut self, id: ThreadId) -> ThreadId {
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let active_thread_id = self.active_thread;
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self.active_thread = id;
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assert!(self.active_thread.index() < self.threads.len());
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active_thread_id
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}
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2020-03-16 18:48:44 -05:00
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/// Get the id of the currently active thread.
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2020-04-06 18:12:13 -05:00
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fn get_active_thread_id(&self) -> ThreadId {
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2020-03-16 18:48:44 -05:00
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self.active_thread
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}
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2020-04-15 23:25:12 -05:00
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2020-04-19 22:52:53 -05:00
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/// Get the total number of threads that were ever spawn by this program.
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fn get_total_thread_count(&self) -> usize {
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self.threads.len()
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}
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2020-04-16 21:40:02 -05:00
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/// Has the given thread terminated?
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fn has_terminated(&self, thread_id: ThreadId) -> bool {
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self.threads[thread_id].state == ThreadState::Terminated
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}
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2020-04-24 17:16:24 -05:00
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/// Enable the thread for execution. The thread must be terminated.
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fn enable_thread(&mut self, thread_id: ThreadId) {
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assert!(self.has_terminated(thread_id));
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self.threads[thread_id].state = ThreadState::Enabled;
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}
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2020-04-24 18:46:51 -05:00
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/// Get a mutable borrow of the currently active thread.
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2020-04-06 18:12:13 -05:00
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fn active_thread_mut(&mut self) -> &mut Thread<'mir, 'tcx> {
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&mut self.threads[self.active_thread]
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}
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2020-04-15 23:25:12 -05:00
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2020-04-24 18:46:51 -05:00
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/// Get a shared borrow of the currently active thread.
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fn active_thread_ref(&self) -> &Thread<'mir, 'tcx> {
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&self.threads[self.active_thread]
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}
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2020-03-16 18:48:44 -05:00
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/// Mark the thread as detached, which means that no other thread will try
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/// to join it and the thread is responsible for cleaning up.
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2020-04-19 18:43:40 -05:00
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fn detach_thread(&mut self, id: ThreadId) -> InterpResult<'tcx> {
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if self.threads[id].join_status != ThreadJoinStatus::Joinable {
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throw_ub_format!("trying to detach thread that was already detached or joined");
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}
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self.threads[id].join_status = ThreadJoinStatus::Detached;
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Ok(())
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}
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2020-04-15 23:25:12 -05:00
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2020-03-16 18:48:44 -05:00
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/// Mark that the active thread tries to join the thread with `joined_thread_id`.
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fn join_thread(&mut self, joined_thread_id: ThreadId) -> InterpResult<'tcx> {
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if self.threads[joined_thread_id].join_status != ThreadJoinStatus::Joinable {
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throw_ub_format!("trying to join a detached or already joined thread");
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2020-04-19 16:21:18 -05:00
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}
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if joined_thread_id == self.active_thread {
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throw_ub_format!("trying to join itself");
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}
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2020-04-19 18:43:40 -05:00
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assert!(
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self.threads
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.iter()
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.all(|thread| thread.state != ThreadState::BlockedOnJoin(joined_thread_id)),
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"a joinable thread already has threads waiting for its termination"
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);
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// Mark the joined thread as being joined so that we detect if other
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// threads try to join it.
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|
self.threads[joined_thread_id].join_status = ThreadJoinStatus::Joined;
|
2020-03-16 18:48:44 -05:00
|
|
|
if self.threads[joined_thread_id].state != ThreadState::Terminated {
|
|
|
|
// The joined thread is still running, we need to wait for it.
|
2020-04-07 22:20:41 -05:00
|
|
|
self.active_thread_mut().state = ThreadState::BlockedOnJoin(joined_thread_id);
|
2020-03-16 18:48:44 -05:00
|
|
|
trace!(
|
|
|
|
"{:?} blocked on {:?} when trying to join",
|
|
|
|
self.active_thread,
|
|
|
|
joined_thread_id
|
|
|
|
);
|
|
|
|
}
|
2020-04-19 16:21:18 -05:00
|
|
|
Ok(())
|
2020-03-16 18:48:44 -05:00
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-06 18:12:13 -05:00
|
|
|
/// Set the name of the active thread.
|
|
|
|
fn set_thread_name(&mut self, new_thread_name: Vec<u8>) {
|
|
|
|
self.active_thread_mut().thread_name = Some(new_thread_name);
|
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
/// Get the name of the active thread.
|
2020-04-24 18:46:51 -05:00
|
|
|
fn get_thread_name(&self) -> InterpResult<'tcx, &[u8]> {
|
|
|
|
if let Some(ref thread_name) = self.active_thread_ref().thread_name {
|
|
|
|
Ok(thread_name)
|
2020-04-19 16:21:18 -05:00
|
|
|
} else {
|
|
|
|
throw_ub_format!("thread {:?} has no name set", self.active_thread)
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2020-04-15 23:25:12 -05:00
|
|
|
/// Allocate a new blockset id.
|
2020-04-07 22:20:41 -05:00
|
|
|
fn create_blockset(&mut self) -> BlockSetId {
|
|
|
|
self.blockset_counter = self.blockset_counter.checked_add(1).unwrap();
|
|
|
|
self.blockset_counter.into()
|
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
|
|
|
/// Block the currently active thread and put it into the given blockset.
|
2020-04-07 22:20:41 -05:00
|
|
|
fn block_active_thread(&mut self, set: BlockSetId) {
|
|
|
|
let state = &mut self.active_thread_mut().state;
|
|
|
|
assert_eq!(*state, ThreadState::Enabled);
|
|
|
|
*state = ThreadState::Blocked(set);
|
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
|
|
|
/// Unblock any one thread from the given blockset if it contains at least
|
|
|
|
/// one. Return the id of the unblocked thread.
|
2020-04-19 16:21:18 -05:00
|
|
|
fn unblock_some_thread(&mut self, set: BlockSetId) -> Option<ThreadId> {
|
2020-04-07 22:20:41 -05:00
|
|
|
for (id, thread) in self.threads.iter_enumerated_mut() {
|
|
|
|
if thread.state == ThreadState::Blocked(set) {
|
|
|
|
trace!("unblocking {:?} in blockset {:?}", id, set);
|
|
|
|
thread.state = ThreadState::Enabled;
|
|
|
|
return Some(id);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
None
|
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-18 17:39:53 -05:00
|
|
|
/// Change the active thread to some enabled thread.
|
|
|
|
fn yield_active_thread(&mut self) {
|
|
|
|
self.yield_active_thread = true;
|
|
|
|
}
|
|
|
|
|
2020-04-16 21:40:02 -05:00
|
|
|
/// Decide which action to take next and on which thread.
|
2020-04-19 16:21:18 -05:00
|
|
|
///
|
|
|
|
/// The currently implemented scheduling policy is the one that is commonly
|
|
|
|
/// used in stateless model checkers such as Loom: run the active thread as
|
|
|
|
/// long as we can and switch only when we have to (the active thread was
|
2020-04-26 16:42:07 -05:00
|
|
|
/// blocked, terminated, or has explicitly asked to be preempted).
|
2020-04-16 21:40:02 -05:00
|
|
|
fn schedule(&mut self) -> InterpResult<'tcx, SchedulingAction> {
|
2020-03-16 18:48:44 -05:00
|
|
|
if self.threads[self.active_thread].check_terminated() {
|
|
|
|
// Check if we need to unblock any threads.
|
|
|
|
for (i, thread) in self.threads.iter_enumerated_mut() {
|
2020-04-07 22:20:41 -05:00
|
|
|
if thread.state == ThreadState::BlockedOnJoin(self.active_thread) {
|
2020-03-16 18:48:44 -05:00
|
|
|
trace!("unblocking {:?} because {:?} terminated", i, self.active_thread);
|
|
|
|
thread.state = ThreadState::Enabled;
|
|
|
|
}
|
|
|
|
}
|
2020-04-16 21:40:02 -05:00
|
|
|
return Ok(SchedulingAction::ExecuteDtors);
|
2020-03-16 18:48:44 -05:00
|
|
|
}
|
2020-04-19 16:21:18 -05:00
|
|
|
if self.threads[MAIN_THREAD].state == ThreadState::Terminated {
|
|
|
|
// The main thread terminated; stop the program.
|
|
|
|
if self.threads.iter().any(|thread| thread.state != ThreadState::Terminated) {
|
2020-04-20 18:57:30 -05:00
|
|
|
// FIXME: This check should be either configurable or just emit
|
|
|
|
// a warning. For example, it seems normal for a program to
|
|
|
|
// terminate without waiting for its detached threads to
|
|
|
|
// terminate. However, this case is not trivial to support
|
|
|
|
// because we also probably do not want to consider the memory
|
|
|
|
// owned by these threads as leaked.
|
2020-04-19 16:21:18 -05:00
|
|
|
throw_unsup_format!("the main thread terminated without waiting for other threads");
|
|
|
|
}
|
|
|
|
return Ok(SchedulingAction::Stop);
|
|
|
|
}
|
2020-04-18 17:39:53 -05:00
|
|
|
if self.threads[self.active_thread].state == ThreadState::Enabled
|
|
|
|
&& !self.yield_active_thread
|
|
|
|
{
|
2020-04-19 16:21:18 -05:00
|
|
|
// The currently active thread is still enabled, just continue with it.
|
2020-04-16 21:40:02 -05:00
|
|
|
return Ok(SchedulingAction::ExecuteStep);
|
2020-03-16 18:48:44 -05:00
|
|
|
}
|
2020-04-19 16:21:18 -05:00
|
|
|
// We need to pick a new thread for execution.
|
2020-04-18 17:39:53 -05:00
|
|
|
for (id, thread) in self.threads.iter_enumerated() {
|
|
|
|
if thread.state == ThreadState::Enabled {
|
2020-04-19 16:21:18 -05:00
|
|
|
if !self.yield_active_thread || id != self.active_thread {
|
2020-04-18 17:39:53 -05:00
|
|
|
self.active_thread = id;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
self.yield_active_thread = false;
|
|
|
|
if self.threads[self.active_thread].state == ThreadState::Enabled {
|
2020-04-16 21:40:02 -05:00
|
|
|
return Ok(SchedulingAction::ExecuteStep);
|
2020-03-16 18:48:44 -05:00
|
|
|
}
|
2020-04-19 16:21:18 -05:00
|
|
|
// We have not found a thread to execute.
|
2020-03-16 18:48:44 -05:00
|
|
|
if self.threads.iter().all(|thread| thread.state == ThreadState::Terminated) {
|
2020-04-19 16:21:18 -05:00
|
|
|
unreachable!();
|
2020-03-16 18:48:44 -05:00
|
|
|
} else {
|
2020-04-07 22:20:41 -05:00
|
|
|
throw_machine_stop!(TerminationInfo::Deadlock);
|
2020-03-16 18:48:44 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
// Public interface to thread management.
|
2020-03-16 18:48:44 -05:00
|
|
|
impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
|
|
|
|
pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
|
2020-04-16 15:32:40 -05:00
|
|
|
/// A workaround for thread-local statics until
|
|
|
|
/// https://github.com/rust-lang/rust/issues/70685 is fixed: change the
|
|
|
|
/// thread-local allocation id with a freshly generated allocation id for
|
|
|
|
/// the currently active thread.
|
|
|
|
fn remap_thread_local_alloc_ids(
|
|
|
|
&self,
|
|
|
|
val: &mut mir::interpret::ConstValue<'tcx>,
|
|
|
|
) -> InterpResult<'tcx> {
|
2020-04-15 16:34:34 -05:00
|
|
|
let this = self.eval_context_ref();
|
2020-04-19 16:21:18 -05:00
|
|
|
match *val {
|
|
|
|
mir::interpret::ConstValue::Scalar(Scalar::Ptr(ref mut ptr)) => {
|
2020-04-16 15:32:40 -05:00
|
|
|
let alloc_id = ptr.alloc_id;
|
|
|
|
let alloc = this.tcx.alloc_map.lock().get(alloc_id);
|
|
|
|
let tcx = this.tcx;
|
|
|
|
let is_thread_local = |def_id| {
|
|
|
|
tcx.codegen_fn_attrs(def_id).flags.contains(CodegenFnAttrFlags::THREAD_LOCAL)
|
|
|
|
};
|
|
|
|
match alloc {
|
|
|
|
Some(GlobalAlloc::Static(def_id)) if is_thread_local(def_id) => {
|
|
|
|
ptr.alloc_id = this.get_or_create_thread_local_alloc_id(def_id)?;
|
|
|
|
}
|
|
|
|
_ => {}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
_ => {
|
|
|
|
// FIXME: Handling only `Scalar` seems to work for now, but at
|
|
|
|
// least in principle thread-locals could be in any constant, so
|
|
|
|
// we should also consider other cases. However, once
|
|
|
|
// https://github.com/rust-lang/rust/issues/70685 gets fixed,
|
|
|
|
// this code will have to be rewritten anyway.
|
|
|
|
}
|
|
|
|
}
|
|
|
|
Ok(())
|
2020-04-15 16:34:34 -05:00
|
|
|
}
|
2020-04-16 15:39:21 -05:00
|
|
|
|
2020-04-16 15:32:40 -05:00
|
|
|
/// Get a thread-specific allocation id for the given thread-local static.
|
|
|
|
/// If needed, allocate a new one.
|
|
|
|
///
|
|
|
|
/// FIXME: This method should be replaced as soon as
|
|
|
|
/// https://github.com/rust-lang/rust/issues/70685 gets fixed.
|
|
|
|
fn get_or_create_thread_local_alloc_id(&self, def_id: DefId) -> InterpResult<'tcx, AllocId> {
|
2020-04-15 16:34:34 -05:00
|
|
|
let this = self.eval_context_ref();
|
2020-04-16 15:32:40 -05:00
|
|
|
let tcx = this.tcx;
|
|
|
|
if let Some(new_alloc_id) = this.machine.threads.get_thread_local_alloc_id(def_id) {
|
|
|
|
// We already have a thread-specific allocation id for this
|
|
|
|
// thread-local static.
|
|
|
|
Ok(new_alloc_id)
|
|
|
|
} else {
|
|
|
|
// We need to allocate a thread-specific allocation id for this
|
|
|
|
// thread-local static.
|
|
|
|
//
|
|
|
|
// At first, we invoke the `const_eval_raw` query and extract the
|
|
|
|
// allocation from it. Unfortunately, we have to duplicate the code
|
|
|
|
// from `Memory::get_global_alloc` that does this.
|
|
|
|
//
|
|
|
|
// Then we store the retrieved allocation back into the `alloc_map`
|
|
|
|
// to get a fresh allocation id, which we can use as a
|
|
|
|
// thread-specific allocation id for the thread-local static.
|
|
|
|
if tcx.is_foreign_item(def_id) {
|
|
|
|
throw_unsup_format!("foreign thread-local statics are not supported");
|
|
|
|
}
|
|
|
|
// Invoke the `const_eval_raw` query.
|
|
|
|
let instance = Instance::mono(tcx.tcx, def_id);
|
|
|
|
let gid = GlobalId { instance, promoted: None };
|
|
|
|
let raw_const =
|
|
|
|
tcx.const_eval_raw(ty::ParamEnv::reveal_all().and(gid)).map_err(|err| {
|
|
|
|
// no need to report anything, the const_eval call takes care of that
|
|
|
|
// for statics
|
|
|
|
assert!(tcx.is_static(def_id));
|
|
|
|
err
|
|
|
|
})?;
|
|
|
|
let id = raw_const.alloc_id;
|
|
|
|
// Extract the allocation from the query result.
|
|
|
|
let mut alloc_map = tcx.alloc_map.lock();
|
|
|
|
let allocation = alloc_map.unwrap_memory(id);
|
|
|
|
// Create a new allocation id for the same allocation in this hacky
|
|
|
|
// way. Internally, `alloc_map` deduplicates allocations, but this
|
|
|
|
// is fine because Miri will make a copy before a first mutable
|
|
|
|
// access.
|
|
|
|
let new_alloc_id = alloc_map.create_memory_alloc(allocation);
|
|
|
|
this.machine.threads.set_thread_local_alloc_id(def_id, new_alloc_id);
|
|
|
|
Ok(new_alloc_id)
|
|
|
|
}
|
2020-04-15 16:34:34 -05:00
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
#[inline]
|
2020-03-16 18:48:44 -05:00
|
|
|
fn create_thread(&mut self) -> InterpResult<'tcx, ThreadId> {
|
|
|
|
let this = self.eval_context_mut();
|
|
|
|
Ok(this.machine.threads.create_thread())
|
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
#[inline]
|
2020-03-16 18:48:44 -05:00
|
|
|
fn detach_thread(&mut self, thread_id: ThreadId) -> InterpResult<'tcx> {
|
|
|
|
let this = self.eval_context_mut();
|
2020-04-19 18:43:40 -05:00
|
|
|
this.machine.threads.detach_thread(thread_id)
|
2020-03-16 18:48:44 -05:00
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
#[inline]
|
2020-03-16 18:48:44 -05:00
|
|
|
fn join_thread(&mut self, joined_thread_id: ThreadId) -> InterpResult<'tcx> {
|
|
|
|
let this = self.eval_context_mut();
|
2020-04-19 16:21:18 -05:00
|
|
|
this.machine.threads.join_thread(joined_thread_id)
|
2020-03-16 18:48:44 -05:00
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
#[inline]
|
2020-03-16 18:48:44 -05:00
|
|
|
fn set_active_thread(&mut self, thread_id: ThreadId) -> InterpResult<'tcx, ThreadId> {
|
|
|
|
let this = self.eval_context_mut();
|
2020-04-06 18:12:13 -05:00
|
|
|
Ok(this.machine.threads.set_active_thread_id(thread_id))
|
2020-03-16 18:48:44 -05:00
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
#[inline]
|
2020-03-16 18:48:44 -05:00
|
|
|
fn get_active_thread(&self) -> InterpResult<'tcx, ThreadId> {
|
|
|
|
let this = self.eval_context_ref();
|
2020-04-06 18:12:13 -05:00
|
|
|
Ok(this.machine.threads.get_active_thread_id())
|
2020-03-16 18:48:44 -05:00
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-19 22:52:53 -05:00
|
|
|
#[inline]
|
|
|
|
fn get_total_thread_count(&self) -> InterpResult<'tcx, usize> {
|
|
|
|
let this = self.eval_context_ref();
|
|
|
|
Ok(this.machine.threads.get_total_thread_count())
|
|
|
|
}
|
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
#[inline]
|
2020-04-16 21:40:02 -05:00
|
|
|
fn has_terminated(&self, thread_id: ThreadId) -> InterpResult<'tcx, bool> {
|
|
|
|
let this = self.eval_context_ref();
|
|
|
|
Ok(this.machine.threads.has_terminated(thread_id))
|
|
|
|
}
|
|
|
|
|
2020-04-24 17:16:24 -05:00
|
|
|
#[inline]
|
|
|
|
fn enable_thread(&mut self, thread_id: ThreadId) -> InterpResult<'tcx> {
|
|
|
|
let this = self.eval_context_mut();
|
|
|
|
this.machine.threads.enable_thread(thread_id);
|
|
|
|
Ok(())
|
|
|
|
}
|
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
#[inline]
|
2020-03-16 18:48:44 -05:00
|
|
|
fn active_thread_stack(&self) -> &[Frame<'mir, 'tcx, Tag, FrameData<'tcx>>] {
|
|
|
|
let this = self.eval_context_ref();
|
|
|
|
this.machine.threads.active_thread_stack()
|
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
#[inline]
|
2020-03-16 18:48:44 -05:00
|
|
|
fn active_thread_stack_mut(&mut self) -> &mut Vec<Frame<'mir, 'tcx, Tag, FrameData<'tcx>>> {
|
|
|
|
let this = self.eval_context_mut();
|
|
|
|
this.machine.threads.active_thread_stack_mut()
|
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
#[inline]
|
2020-04-06 18:12:13 -05:00
|
|
|
fn set_active_thread_name(&mut self, new_thread_name: Vec<u8>) -> InterpResult<'tcx, ()> {
|
|
|
|
let this = self.eval_context_mut();
|
|
|
|
Ok(this.machine.threads.set_thread_name(new_thread_name))
|
|
|
|
}
|
2020-04-15 23:25:12 -05:00
|
|
|
|
2020-04-19 16:21:18 -05:00
|
|
|
#[inline]
|
2020-04-24 18:46:51 -05:00
|
|
|
fn get_active_thread_name<'c>(&'c self) -> InterpResult<'tcx, &'c [u8]>
|
|
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where
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'mir: 'c,
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{
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let this = self.eval_context_ref();
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2020-04-19 16:21:18 -05:00
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this.machine.threads.get_thread_name()
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}
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#[inline]
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2020-04-07 22:20:41 -05:00
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fn create_blockset(&mut self) -> InterpResult<'tcx, BlockSetId> {
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let this = self.eval_context_mut();
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Ok(this.machine.threads.create_blockset())
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}
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2020-04-15 23:25:12 -05:00
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2020-04-19 16:21:18 -05:00
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#[inline]
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2020-04-07 22:20:41 -05:00
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fn block_active_thread(&mut self, set: BlockSetId) -> InterpResult<'tcx> {
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let this = self.eval_context_mut();
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Ok(this.machine.threads.block_active_thread(set))
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}
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2020-04-15 23:25:12 -05:00
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2020-04-19 16:21:18 -05:00
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|
#[inline]
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|
fn unblock_some_thread(&mut self, set: BlockSetId) -> InterpResult<'tcx, Option<ThreadId>> {
|
2020-04-07 22:20:41 -05:00
|
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|
let this = self.eval_context_mut();
|
2020-04-19 16:21:18 -05:00
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|
Ok(this.machine.threads.unblock_some_thread(set))
|
2020-04-07 22:20:41 -05:00
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}
|
2020-04-15 23:25:12 -05:00
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|
2020-04-19 16:21:18 -05:00
|
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|
#[inline]
|
2020-04-18 17:39:53 -05:00
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|
fn yield_active_thread(&mut self) -> InterpResult<'tcx> {
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|
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|
let this = self.eval_context_mut();
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|
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|
this.machine.threads.yield_active_thread();
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|
Ok(())
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|
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|
}
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|
2020-04-16 21:40:02 -05:00
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|
/// Decide which action to take next and on which thread.
|
2020-04-19 16:21:18 -05:00
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|
#[inline]
|
2020-04-16 21:40:02 -05:00
|
|
|
fn schedule(&mut self) -> InterpResult<'tcx, SchedulingAction> {
|
2020-03-16 18:48:44 -05:00
|
|
|
let this = self.eval_context_mut();
|
2020-04-15 16:34:34 -05:00
|
|
|
this.machine.threads.schedule()
|
2020-03-16 18:48:44 -05:00
|
|
|
}
|
|
|
|
}
|