use std::borrow::Cow;
use std::cell::RefCell;
+use std::num::NonZeroU64;
use std::rc::Rc;
+use std::time::Instant;
use rand::rngs::StdRng;
-use rustc::hir::def_id::DefId;
-use rustc::ty::{self, layout::{Size, LayoutOf}, Ty, TyCtxt};
+use rustc_data_structures::fx::FxHashMap;
use rustc::mir;
-use syntax::{attr, source_map::Span, symbol::sym};
+use rustc::ty::{
+ self,
+ layout::{LayoutOf, Size},
+ Ty,
+};
+use rustc_ast::attr;
+use rustc_span::{source_map::Span, symbol::{sym, Symbol}};
use crate::*;
/// Extra data for Stacked Borrows.
pub call_id: stacked_borrows::CallId,
- /// If this is Some(), then this is a special "catch unwind" frame (the frame of the closure
- /// called by `__rustc_maybe_catch_panic`). When this frame is popped during unwinding a panic,
- /// we stop unwinding, use the `CatchUnwindData` to
- /// store the panic payload, and continue execution in the parent frame.
- pub catch_panic: Option<CatchUnwindData<'tcx>>,
+ /// If this is Some(), then this is a special "catch unwind" frame (the frame of `try_fn`
+ /// called by `try`). When this frame is popped during unwinding a panic,
+ /// we stop unwinding, use the `CatchUnwindData` to handle catching.
+ pub catch_unwind: Option<CatchUnwindData<'tcx>>,
}
-
/// Extra memory kinds
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
pub enum MiriMemoryKind {
C,
/// Windows `HeapAlloc` memory.
WinHeap,
- /// Part of env var emulation.
+ /// Memory for args, errno, extern statics and other parts of the machine-managed environment.
+ /// This memory may leak.
+ Machine,
+ /// Memory for env vars. Separate from `Machine` because we clean it up and leak-check it.
Env,
- /// Statics.
- Static,
+ /// Globals copied from `tcx`.
+ /// This memory may leak.
+ Global,
}
impl Into<MemoryKind<MiriMemoryKind>> for MiriMemoryKind {
/// Extra per-allocation data
#[derive(Debug, Clone)]
pub struct AllocExtra {
- /// Stacked Borrows state is only added if validation is enabled.
+ /// Stacked Borrows state is only added if it is enabled.
pub stacked_borrows: Option<stacked_borrows::AllocExtra>,
}
/// Extra global memory data
#[derive(Clone, Debug)]
pub struct MemoryExtra {
- pub stacked_borrows: stacked_borrows::MemoryExtra,
+ pub stacked_borrows: Option<stacked_borrows::MemoryExtra>,
pub intptrcast: intptrcast::MemoryExtra,
+ /// Mapping extern static names to their canonical allocation.
+ extern_statics: FxHashMap<Symbol, AllocId>,
+
/// The random number generator used for resolving non-determinism.
+ /// Needs to be queried by ptr_to_int, hence needs interior mutability.
pub(crate) rng: RefCell<StdRng>,
- /// Whether to enforce the validity invariant.
- pub(crate) validate: bool,
+ /// An allocation ID to report when it is being allocated
+ /// (helps for debugging memory leaks).
+ tracked_alloc_id: Option<AllocId>,
}
impl MemoryExtra {
- pub fn new(rng: StdRng, validate: bool) -> Self {
+ pub fn new(rng: StdRng, stacked_borrows: bool, tracked_pointer_tag: Option<PtrId>, tracked_alloc_id: Option<AllocId>) -> Self {
+ let stacked_borrows = if stacked_borrows {
+ Some(Rc::new(RefCell::new(stacked_borrows::GlobalState::new(tracked_pointer_tag))))
+ } else {
+ None
+ };
MemoryExtra {
- stacked_borrows: Default::default(),
+ stacked_borrows,
intptrcast: Default::default(),
+ extern_statics: FxHashMap::default(),
rng: RefCell::new(rng),
- validate,
+ tracked_alloc_id,
+ }
+ }
+
+ /// Sets up the "extern statics" for this machine.
+ pub fn init_extern_statics<'tcx, 'mir>(
+ this: &mut MiriEvalContext<'mir, 'tcx>,
+ ) -> InterpResult<'tcx> {
+ match this.tcx.sess.target.target.target_os.as_str() {
+ "linux" => {
+ // "__cxa_thread_atexit_impl"
+ // This should be all-zero, pointer-sized.
+ let layout = this.layout_of(this.tcx.types.usize)?;
+ let place = this.allocate(layout, MiriMemoryKind::Machine.into());
+ this.write_scalar(Scalar::from_machine_usize(0, &*this.tcx), place.into())?;
+ this.memory
+ .extra
+ .extern_statics
+ .insert(Symbol::intern("__cxa_thread_atexit_impl"), place.ptr.assert_ptr().alloc_id)
+ .unwrap_none();
+ // "environ"
+ this.memory
+ .extra
+ .extern_statics
+ .insert(Symbol::intern("environ"), this.machine.env_vars.environ.unwrap().ptr.assert_ptr().alloc_id)
+ .unwrap_none();
+ }
+ _ => {} // No "extern statics" supported on this target
}
+ Ok(())
}
}
pub struct Evaluator<'tcx> {
/// Environment variables set by `setenv`.
/// Miri does not expose env vars from the host to the emulated program.
- pub(crate) env_vars: EnvVars,
+ pub(crate) env_vars: EnvVars<'tcx>,
/// Program arguments (`Option` because we can only initialize them after creating the ecx).
/// These are *pointers* to argc/argv because macOS.
/// and random number generation is delegated to the host.
pub(crate) communicate: bool,
+ /// Whether to enforce the validity invariant.
+ pub(crate) validate: bool,
+
pub(crate) file_handler: FileHandler,
+ pub(crate) dir_handler: DirHandler,
/// The temporary used for storing the argument of
/// the call to `miri_start_panic` (the panic payload) when unwinding.
- pub(crate) panic_payload: Option<ImmTy<'tcx, Tag>>
+ /// This is pointer-sized, and matches the `Payload` type in `src/libpanic_unwind/miri.rs`.
+ pub(crate) panic_payload: Option<Scalar<Tag>>,
+
+ /// The "time anchor" for this machine's monotone clock (for `Instant` simulation).
+ pub(crate) time_anchor: Instant,
}
impl<'tcx> Evaluator<'tcx> {
- pub(crate) fn new(communicate: bool) -> Self {
+ pub(crate) fn new(communicate: bool, validate: bool) -> Self {
Evaluator {
// `env_vars` could be initialized properly here if `Memory` were available before
// calling this method.
last_error: None,
tls: TlsData::default(),
communicate,
+ validate,
file_handler: Default::default(),
- panic_payload: None
+ dir_handler: Default::default(),
+ panic_payload: None,
+ time_anchor: Instant::now(),
}
}
}
/// A little trait that's useful to be inherited by extension traits.
pub trait MiriEvalContextExt<'mir, 'tcx> {
- fn eval_context_ref(&self) -> &MiriEvalContext<'mir, 'tcx>;
- fn eval_context_mut(&mut self) -> &mut MiriEvalContext<'mir, 'tcx>;
+ fn eval_context_ref<'a>(&'a self) -> &'a MiriEvalContext<'mir, 'tcx>;
+ fn eval_context_mut<'a>(&'a mut self) -> &'a mut MiriEvalContext<'mir, 'tcx>;
}
impl<'mir, 'tcx> MiriEvalContextExt<'mir, 'tcx> for MiriEvalContext<'mir, 'tcx> {
#[inline(always)]
/// Machine hook implementations.
impl<'mir, 'tcx> Machine<'mir, 'tcx> for Evaluator<'tcx> {
- type MemoryKinds = MiriMemoryKind;
+ type MemoryKind = MiriMemoryKind;
type FrameExtra = FrameData<'tcx>;
type MemoryExtra = MemoryExtra;
type PointerTag = Tag;
type ExtraFnVal = Dlsym;
- type MemoryMap = MonoHashMap<
- AllocId,
- (
- MemoryKind<MiriMemoryKind>,
- Allocation<Tag, Self::AllocExtra>,
- ),
- >;
+ type MemoryMap =
+ MonoHashMap<AllocId, (MemoryKind<MiriMemoryKind>, Allocation<Tag, Self::AllocExtra>)>;
- const STATIC_KIND: Option<MiriMemoryKind> = Some(MiriMemoryKind::Static);
+ const GLOBAL_KIND: Option<MiriMemoryKind> = Some(MiriMemoryKind::Global);
const CHECK_ALIGN: bool = true;
#[inline(always)]
fn enforce_validity(ecx: &InterpCx<'mir, 'tcx, Self>) -> bool {
- ecx.memory.extra.validate
+ ecx.machine.validate
}
#[inline(always)]
- fn find_fn(
+ fn find_mir_or_eval_fn(
ecx: &mut InterpCx<'mir, 'tcx, Self>,
+ _span: Span,
instance: ty::Instance<'tcx>,
args: &[OpTy<'tcx, Tag>],
ret: Option<(PlaceTy<'tcx, Tag>, mir::BasicBlock)>,
unwind: Option<mir::BasicBlock>,
) -> InterpResult<'tcx, Option<&'mir mir::Body<'tcx>>> {
- ecx.find_fn(instance, args, ret, unwind)
+ ecx.find_mir_or_eval_fn(instance, args, ret, unwind)
}
#[inline(always)]
ecx.call_intrinsic(span, instance, args, ret, unwind)
}
+ #[inline(always)]
+ fn assert_panic(
+ ecx: &mut InterpCx<'mir, 'tcx, Self>,
+ msg: &mir::AssertMessage<'tcx>,
+ unwind: Option<mir::BasicBlock>,
+ ) -> InterpResult<'tcx> {
+ ecx.assert_panic(msg, unwind)
+ }
+
+ #[inline(always)]
+ fn abort(_ecx: &mut InterpCx<'mir, 'tcx, Self>) -> InterpResult<'tcx, !> {
+ throw_machine_stop!(TerminationInfo::Abort(None))
+ }
+
#[inline(always)]
fn binary_ptr_op(
ecx: &rustc_mir::interpret::InterpCx<'mir, 'tcx, Self>,
dest: PlaceTy<'tcx, Tag>,
) -> InterpResult<'tcx> {
trace!("box_alloc for {:?}", dest.layout.ty);
+ let layout = ecx.layout_of(dest.layout.ty.builtin_deref(false).unwrap().ty)?;
+ // First argument: `size`.
+ // (`0` is allowed here -- this is expected to be handled by the lang item).
+ let size = Scalar::from_uint(layout.size.bytes(), ecx.pointer_size());
+
+ // Second argument: `align`.
+ let align = Scalar::from_uint(layout.align.abi.bytes(), ecx.pointer_size());
+
// Call the `exchange_malloc` lang item.
let malloc = ecx.tcx.lang_items().exchange_malloc_fn().unwrap();
let malloc = ty::Instance::mono(ecx.tcx.tcx, malloc);
- let malloc_mir = ecx.load_mir(malloc.def, None)?;
- ecx.push_stack_frame(
+ ecx.call_function(
malloc,
- malloc_mir.span,
- malloc_mir,
+ &[size.into(), align.into()],
Some(dest),
// Don't do anything when we are done. The `statement()` function will increment
// the old stack frame's stmt counter to the next statement, which means that when
// `exchange_malloc` returns, we go on evaluating exactly where we want to be.
StackPopCleanup::None { cleanup: true },
)?;
-
- let mut args = ecx.frame().body.args_iter();
- let layout = ecx.layout_of(dest.layout.ty.builtin_deref(false).unwrap().ty)?;
-
- // First argument: `size`.
- // (`0` is allowed here -- this is expected to be handled by the lang item).
- let arg = ecx.local_place(args.next().unwrap())?;
- let size = layout.size.bytes();
- ecx.write_scalar(Scalar::from_uint(size, arg.layout.size), arg)?;
-
- // Second argument: `align`.
- let arg = ecx.local_place(args.next().unwrap())?;
- let align = layout.align.abi.bytes();
- ecx.write_scalar(Scalar::from_uint(align, arg.layout.size), arg)?;
-
- // No more arguments.
- args.next().expect_none("`exchange_malloc` lang item has more arguments than expected");
Ok(())
}
- fn find_foreign_static(
- tcx: TyCtxt<'tcx>,
- def_id: DefId,
- ) -> InterpResult<'tcx, Cow<'tcx, Allocation>> {
+ fn canonical_alloc_id(mem: &Memory<'mir, 'tcx, Self>, id: AllocId) -> AllocId {
+ let tcx = mem.tcx;
+ // Figure out if this is an extern static, and if yes, which one.
+ let def_id = match tcx.alloc_map.lock().get(id) {
+ Some(GlobalAlloc::Static(def_id)) if tcx.is_foreign_item(def_id) => def_id,
+ _ => {
+ // No need to canonicalize anything.
+ return id;
+ }
+ };
let attrs = tcx.get_attrs(def_id);
let link_name = match attr::first_attr_value_str_by_name(&attrs, sym::link_name) {
- Some(name) => name.as_str(),
- None => tcx.item_name(def_id).as_str(),
- };
-
- let alloc = match &*link_name {
- "__cxa_thread_atexit_impl" => {
- // This should be all-zero, pointer-sized.
- let size = tcx.data_layout.pointer_size;
- let data = vec![0; size.bytes() as usize];
- Allocation::from_bytes(&data, tcx.data_layout.pointer_align.abi)
- }
- _ => throw_unsup_format!("can't access foreign static: {}", link_name),
+ Some(name) => name,
+ None => tcx.item_name(def_id),
};
- Ok(Cow::Owned(alloc))
- }
-
- #[inline(always)]
- fn before_terminator(_ecx: &mut InterpCx<'mir, 'tcx, Self>) -> InterpResult<'tcx> {
- // We are not interested in detecting loops.
- Ok(())
+ // Check if we know this one.
+ if let Some(canonical_id) = mem.extra.extern_statics.get(&link_name) {
+ trace!("canonical_alloc_id: {:?} ({}) -> {:?}", id, link_name, canonical_id);
+ *canonical_id
+ } else {
+ // Return original id; `Memory::get_static_alloc` will throw an error.
+ id
+ }
}
- fn tag_allocation<'b>(
+ fn init_allocation_extra<'b>(
memory_extra: &MemoryExtra,
id: AllocId,
alloc: Cow<'b, Allocation>,
- kind: Option<MemoryKind<Self::MemoryKinds>>,
- ) -> (
- Cow<'b, Allocation<Self::PointerTag, Self::AllocExtra>>,
- Self::PointerTag,
- ) {
+ kind: Option<MemoryKind<Self::MemoryKind>>,
+ ) -> (Cow<'b, Allocation<Self::PointerTag, Self::AllocExtra>>, Self::PointerTag) {
+ if Some(id) == memory_extra.tracked_alloc_id {
+ register_diagnostic(NonHaltingDiagnostic::CreatedAlloc(id));
+ }
+
let kind = kind.expect("we set our STATIC_KIND so this cannot be None");
let alloc = alloc.into_owned();
- let (stacks, base_tag) = if !memory_extra.validate {
- (None, Tag::Untagged)
- } else {
- let (stacks, base_tag) = Stacks::new_allocation(
- id,
- alloc.size,
- Rc::clone(&memory_extra.stacked_borrows),
- kind,
- );
- (Some(stacks), base_tag)
- };
- let mut stacked_borrows = memory_extra.stacked_borrows.borrow_mut();
+ let (stacks, base_tag) =
+ if let Some(stacked_borrows) = memory_extra.stacked_borrows.as_ref() {
+ let (stacks, base_tag) =
+ Stacks::new_allocation(id, alloc.size, Rc::clone(stacked_borrows), kind);
+ (Some(stacks), base_tag)
+ } else {
+ // No stacks, no tag.
+ (None, Tag::Untagged)
+ };
+ let mut stacked_borrows = memory_extra.stacked_borrows.as_ref().map(|sb| sb.borrow_mut());
let alloc: Allocation<Tag, Self::AllocExtra> = alloc.with_tags_and_extra(
|alloc| {
- if !memory_extra.validate {
- Tag::Untagged
+ if let Some(stacked_borrows) = stacked_borrows.as_mut() {
+ // Only globals may already contain pointers at this point
+ assert_eq!(kind, MiriMemoryKind::Global.into());
+ stacked_borrows.global_base_ptr(alloc)
} else {
- // Only statics may already contain pointers at this point
- assert_eq!(kind, MiriMemoryKind::Static.into());
- stacked_borrows.static_base_ptr(alloc)
+ Tag::Untagged
}
},
- AllocExtra {
- stacked_borrows: stacks,
- },
+ AllocExtra { stacked_borrows: stacks },
);
(Cow::Owned(alloc), base_tag)
}
#[inline(always)]
- fn tag_static_base_pointer(memory_extra: &MemoryExtra, id: AllocId) -> Self::PointerTag {
- if !memory_extra.validate {
- Tag::Untagged
+ fn tag_global_base_pointer(memory_extra: &MemoryExtra, id: AllocId) -> Self::PointerTag {
+ if let Some(stacked_borrows) = memory_extra.stacked_borrows.as_ref() {
+ stacked_borrows.borrow_mut().global_base_ptr(id)
} else {
- memory_extra
- .stacked_borrows
- .borrow_mut()
- .static_base_ptr(id)
+ Tag::Untagged
}
}
kind: mir::RetagKind,
place: PlaceTy<'tcx, Tag>,
) -> InterpResult<'tcx> {
- if !Self::enforce_validity(ecx) {
+ if ecx.memory.extra.stacked_borrows.is_none() {
// No tracking.
Ok(())
} else {
}
#[inline(always)]
- fn stack_push(
- ecx: &mut InterpCx<'mir, 'tcx, Self>,
- ) -> InterpResult<'tcx, FrameData<'tcx>> {
- Ok(FrameData {
- call_id: ecx.memory.extra.stacked_borrows.borrow_mut().new_call(),
- catch_panic: None,
- })
+ fn stack_push(ecx: &mut InterpCx<'mir, 'tcx, Self>) -> InterpResult<'tcx, FrameData<'tcx>> {
+ let stacked_borrows = ecx.memory.extra.stacked_borrows.as_ref();
+ let call_id = stacked_borrows.map_or(NonZeroU64::new(1).unwrap(), |stacked_borrows| {
+ stacked_borrows.borrow_mut().new_call()
+ });
+ Ok(FrameData { call_id, catch_unwind: None })
}
#[inline(always)]
fn stack_pop(
ecx: &mut InterpCx<'mir, 'tcx, Self>,
extra: FrameData<'tcx>,
- unwinding: bool
- ) -> InterpResult<'tcx, StackPopInfo> {
+ unwinding: bool,
+ ) -> InterpResult<'tcx, StackPopJump> {
ecx.handle_stack_pop(extra, unwinding)
}
fn may_leak(self) -> bool {
use self::MiriMemoryKind::*;
match self {
- Rust | C | WinHeap => false,
- Env | Static => true,
+ Rust | C | WinHeap | Env => false,
+ Machine | Global => true,
}
}
}