2 use std::num::NonZeroUsize;
3 use std::time::Duration;
7 use rustc_hir::def_id::{DefId, CRATE_DEF_INDEX};
9 use rustc_middle::ty::{
11 layout::{LayoutOf, TyAndLayout},
14 use rustc_span::{def_id::CrateNum, Symbol};
15 use rustc_target::abi::{Align, FieldsShape, Size, Variants};
16 use rustc_target::spec::abi::Abi;
22 impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
24 const UNIX_IO_ERROR_TABLE: &[(std::io::ErrorKind, &str)] = {
25 use std::io::ErrorKind::*;
27 (ConnectionRefused, "ECONNREFUSED"),
28 (ConnectionReset, "ECONNRESET"),
29 (PermissionDenied, "EPERM"),
30 (BrokenPipe, "EPIPE"),
31 (NotConnected, "ENOTCONN"),
32 (ConnectionAborted, "ECONNABORTED"),
33 (AddrNotAvailable, "EADDRNOTAVAIL"),
34 (AddrInUse, "EADDRINUSE"),
36 (Interrupted, "EINTR"),
37 (InvalidInput, "EINVAL"),
38 (TimedOut, "ETIMEDOUT"),
39 (AlreadyExists, "EEXIST"),
40 (WouldBlock, "EWOULDBLOCK"),
41 (DirectoryNotEmpty, "ENOTEMPTY"),
45 /// Gets an instance for a path.
46 fn try_resolve_did<'tcx>(tcx: TyCtxt<'tcx>, path: &[&str]) -> Option<DefId> {
47 tcx.crates(()).iter().find(|&&krate| tcx.crate_name(krate).as_str() == path[0]).and_then(
49 let krate = DefId { krate: *krate, index: CRATE_DEF_INDEX };
50 let mut items = tcx.module_children(krate);
51 let mut path_it = path.iter().skip(1).peekable();
53 while let Some(segment) = path_it.next() {
54 for item in mem::take(&mut items).iter() {
55 if item.ident.name.as_str() == *segment {
56 if path_it.peek().is_none() {
57 return Some(item.res.def_id());
60 items = tcx.module_children(item.res.def_id());
70 pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
71 /// Gets an instance for a path.
72 fn resolve_path(&self, path: &[&str]) -> ty::Instance<'tcx> {
73 let did = try_resolve_did(self.eval_context_ref().tcx.tcx, path)
74 .unwrap_or_else(|| panic!("failed to find required Rust item: {:?}", path));
75 ty::Instance::mono(self.eval_context_ref().tcx.tcx, did)
78 /// Evaluates the scalar at the specified path. Returns Some(val)
79 /// if the path could be resolved, and None otherwise
80 fn eval_path_scalar(&self, path: &[&str]) -> InterpResult<'tcx, Scalar<Tag>> {
81 let this = self.eval_context_ref();
82 let instance = this.resolve_path(path);
83 let cid = GlobalId { instance, promoted: None };
84 let const_val = this.eval_to_allocation(cid)?;
85 let const_val = this.read_scalar(&const_val.into())?;
86 return Ok(const_val.check_init()?);
89 /// Helper function to get a `libc` constant as a `Scalar`.
90 fn eval_libc(&self, name: &str) -> InterpResult<'tcx, Scalar<Tag>> {
91 self.eval_path_scalar(&["libc", name])
94 /// Helper function to get a `libc` constant as an `i32`.
95 fn eval_libc_i32(&self, name: &str) -> InterpResult<'tcx, i32> {
96 // TODO: Cache the result.
97 self.eval_libc(name)?.to_i32()
100 /// Helper function to get a `windows` constant as a `Scalar`.
101 fn eval_windows(&self, module: &str, name: &str) -> InterpResult<'tcx, Scalar<Tag>> {
102 self.eval_context_ref().eval_path_scalar(&["std", "sys", "windows", module, name])
105 /// Helper function to get a `windows` constant as a `u64`.
106 fn eval_windows_u64(&self, module: &str, name: &str) -> InterpResult<'tcx, u64> {
107 // TODO: Cache the result.
108 self.eval_windows(module, name)?.to_u64()
111 /// Helper function to get the `TyAndLayout` of a `libc` type
112 fn libc_ty_layout(&self, name: &str) -> InterpResult<'tcx, TyAndLayout<'tcx>> {
113 let this = self.eval_context_ref();
114 let ty = this.resolve_path(&["libc", name]).ty(*this.tcx, ty::ParamEnv::reveal_all());
118 /// Helper function to get the `TyAndLayout` of a `windows` type
119 fn windows_ty_layout(&self, name: &str) -> InterpResult<'tcx, TyAndLayout<'tcx>> {
120 let this = self.eval_context_ref();
122 .resolve_path(&["std", "sys", "windows", "c", name])
123 .ty(*this.tcx, ty::ParamEnv::reveal_all());
127 /// Project to the given *named* field of the mplace (which must be a struct or union type).
128 fn mplace_field_named(
130 mplace: &MPlaceTy<'tcx, Tag>,
132 ) -> InterpResult<'tcx, MPlaceTy<'tcx, Tag>> {
133 let this = self.eval_context_ref();
134 let adt = mplace.layout.ty.ty_adt_def().unwrap();
135 for (idx, field) in adt.non_enum_variant().fields.iter().enumerate() {
136 if field.name.as_str() == name {
137 return this.mplace_field(mplace, idx);
140 bug!("No field named {} in type {}", name, mplace.layout.ty);
143 /// Write an int of the appropriate size to `dest`. The target type may be signed or unsigned,
144 /// we try to do the right thing anyway. `i128` can fit all integer types except for `u128` so
145 /// this method is fine for almost all integer types.
146 fn write_int(&mut self, i: impl Into<i128>, dest: &PlaceTy<'tcx, Tag>) -> InterpResult<'tcx> {
147 assert!(dest.layout.abi.is_scalar(), "write_int on non-scalar type {}", dest.layout.ty);
148 let val = if dest.layout.abi.is_signed() {
149 Scalar::from_int(i, dest.layout.size)
151 Scalar::from_uint(u64::try_from(i.into()).unwrap(), dest.layout.size)
153 self.eval_context_mut().write_scalar(val, dest)
156 /// Write the first N fields of the given place.
160 dest: &MPlaceTy<'tcx, Tag>,
161 ) -> InterpResult<'tcx> {
162 let this = self.eval_context_mut();
163 for (idx, &val) in values.iter().enumerate() {
164 let field = this.mplace_field(dest, idx)?;
165 this.write_int(val, &field.into())?;
170 /// Write the given fields of the given place.
171 fn write_int_fields_named(
173 values: &[(&str, i128)],
174 dest: &MPlaceTy<'tcx, Tag>,
175 ) -> InterpResult<'tcx> {
176 let this = self.eval_context_mut();
177 for &(name, val) in values.iter() {
178 let field = this.mplace_field_named(dest, name)?;
179 this.write_int(val, &field.into())?;
184 /// Write a 0 of the appropriate size to `dest`.
185 fn write_null(&mut self, dest: &PlaceTy<'tcx, Tag>) -> InterpResult<'tcx> {
186 self.write_int(0, dest)
189 /// Test if this pointer equals 0.
190 fn ptr_is_null(&self, ptr: Pointer<Option<Tag>>) -> InterpResult<'tcx, bool> {
191 let this = self.eval_context_ref();
192 let null = Scalar::null_ptr(this);
193 this.ptr_eq(Scalar::from_maybe_pointer(ptr, this), null)
196 /// Get the `Place` for a local
197 fn local_place(&mut self, local: mir::Local) -> InterpResult<'tcx, PlaceTy<'tcx, Tag>> {
198 let this = self.eval_context_mut();
199 let place = mir::Place { local: local, projection: List::empty() };
200 this.eval_place(place)
203 /// Generate some random bytes, and write them to `dest`.
204 fn gen_random(&mut self, ptr: Pointer<Option<Tag>>, len: u64) -> InterpResult<'tcx> {
205 // Some programs pass in a null pointer and a length of 0
206 // to their platform's random-generation function (e.g. getrandom())
207 // on Linux. For compatibility with these programs, we don't perform
208 // any additional checks - it's okay if the pointer is invalid,
209 // since we wouldn't actually be writing to it.
213 let this = self.eval_context_mut();
215 let mut data = vec![0; usize::try_from(len).unwrap()];
217 if this.machine.communicate() {
218 // Fill the buffer using the host's rng.
219 getrandom::getrandom(&mut data)
220 .map_err(|err| err_unsup_format!("host getrandom failed: {}", err))?;
222 let rng = this.machine.rng.get_mut();
223 rng.fill_bytes(&mut data);
226 this.write_bytes_ptr(ptr, data.iter().copied())
229 /// Call a function: Push the stack frame and pass the arguments.
230 /// For now, arguments must be scalars (so that the caller does not have to know the layout).
233 f: ty::Instance<'tcx>,
235 args: &[Immediate<Tag>],
236 dest: Option<&PlaceTy<'tcx, Tag>>,
237 stack_pop: StackPopCleanup,
238 ) -> InterpResult<'tcx> {
239 let this = self.eval_context_mut();
240 let param_env = ty::ParamEnv::reveal_all(); // in Miri this is always the param_env we use... and this.param_env is private.
241 let callee_abi = f.ty(*this.tcx, param_env).fn_sig(*this.tcx).abi();
242 if this.machine.enforce_abi && callee_abi != caller_abi {
244 "calling a function with ABI {} using caller ABI {}",
251 let mir = &*this.load_mir(f.def, None)?;
252 this.push_stack_frame(f, mir, dest, stack_pop)?;
254 // Initialize arguments.
255 let mut callee_args = this.frame().body.args_iter();
257 let callee_arg = this.local_place(
260 .ok_or_else(|| err_ub_format!("callee has fewer arguments than expected"))?,
262 this.write_immediate(*arg, &callee_arg)?;
264 if callee_args.next().is_some() {
265 throw_ub_format!("callee has more arguments than expected");
271 /// Visits the memory covered by `place`, sensitive to freezing: the 2nd parameter
272 /// of `action` will be true if this is frozen, false if this is in an `UnsafeCell`.
273 /// The range is relative to `place`.
274 fn visit_freeze_sensitive(
276 place: &MPlaceTy<'tcx, Tag>,
278 mut action: impl FnMut(AllocRange, bool) -> InterpResult<'tcx>,
279 ) -> InterpResult<'tcx> {
280 let this = self.eval_context_ref();
281 trace!("visit_frozen(place={:?}, size={:?})", *place, size);
284 this.size_and_align_of_mplace(place)?
285 .map(|(size, _)| size)
286 .unwrap_or_else(|| place.layout.size)
288 // Store how far we proceeded into the place so far. Everything to the left of
289 // this offset has already been handled, in the sense that the frozen parts
290 // have had `action` called on them.
291 let start_addr = place.ptr.addr();
292 let mut cur_addr = start_addr;
293 // Called when we detected an `UnsafeCell` at the given offset and size.
294 // Calls `action` and advances `cur_ptr`.
295 let mut unsafe_cell_action = |unsafe_cell_ptr: &Pointer<Option<Tag>>,
296 unsafe_cell_size: Size| {
297 // We assume that we are given the fields in increasing offset order,
298 // and nothing else changes.
299 let unsafe_cell_addr = unsafe_cell_ptr.addr();
300 assert!(unsafe_cell_addr >= cur_addr);
301 let frozen_size = unsafe_cell_addr - cur_addr;
302 // Everything between the cur_ptr and this `UnsafeCell` is frozen.
303 if frozen_size != Size::ZERO {
304 action(alloc_range(cur_addr - start_addr, frozen_size), /*frozen*/ true)?;
306 cur_addr += frozen_size;
307 // This `UnsafeCell` is NOT frozen.
308 if unsafe_cell_size != Size::ZERO {
310 alloc_range(cur_addr - start_addr, unsafe_cell_size),
314 cur_addr += unsafe_cell_size;
320 let mut visitor = UnsafeCellVisitor {
322 unsafe_cell_action: |place| {
323 trace!("unsafe_cell_action on {:?}", place.ptr);
324 // We need a size to go on.
325 let unsafe_cell_size = this
326 .size_and_align_of_mplace(place)?
327 .map(|(size, _)| size)
328 // for extern types, just cover what we can
329 .unwrap_or_else(|| place.layout.size);
330 // Now handle this `UnsafeCell`, unless it is empty.
331 if unsafe_cell_size != Size::ZERO {
332 unsafe_cell_action(&place.ptr, unsafe_cell_size)
338 visitor.visit_value(place)?;
340 // The part between the end_ptr and the end of the place is also frozen.
341 // So pretend there is a 0-sized `UnsafeCell` at the end.
342 unsafe_cell_action(&place.ptr.offset(size, this)?, Size::ZERO)?;
346 /// Visiting the memory covered by a `MemPlace`, being aware of
347 /// whether we are inside an `UnsafeCell` or not.
348 struct UnsafeCellVisitor<'ecx, 'mir, 'tcx, F>
350 F: FnMut(&MPlaceTy<'tcx, Tag>) -> InterpResult<'tcx>,
352 ecx: &'ecx MiriEvalContext<'mir, 'tcx>,
353 unsafe_cell_action: F,
356 impl<'ecx, 'mir, 'tcx: 'mir, F> ValueVisitor<'mir, 'tcx, Evaluator<'mir, 'tcx>>
357 for UnsafeCellVisitor<'ecx, 'mir, 'tcx, F>
359 F: FnMut(&MPlaceTy<'tcx, Tag>) -> InterpResult<'tcx>,
361 type V = MPlaceTy<'tcx, Tag>;
364 fn ecx(&self) -> &MiriEvalContext<'mir, 'tcx> {
368 // Hook to detect `UnsafeCell`.
369 fn visit_value(&mut self, v: &MPlaceTy<'tcx, Tag>) -> InterpResult<'tcx> {
370 trace!("UnsafeCellVisitor: {:?} {:?}", *v, v.layout.ty);
371 let is_unsafe_cell = match v.layout.ty.kind() {
373 Some(adt.did()) == self.ecx.tcx.lang_items().unsafe_cell_type(),
377 // We do not have to recurse further, this is an `UnsafeCell`.
378 (self.unsafe_cell_action)(v)
379 } else if self.ecx.type_is_freeze(v.layout.ty) {
380 // This is `Freeze`, there cannot be an `UnsafeCell`
382 } else if matches!(v.layout.fields, FieldsShape::Union(..)) {
383 // A (non-frozen) union. We fall back to whatever the type says.
384 (self.unsafe_cell_action)(v)
386 // We want to not actually read from memory for this visit. So, before
387 // walking this value, we have to make sure it is not a
388 // `Variants::Multiple`.
389 match v.layout.variants {
390 Variants::Multiple { .. } => {
391 // A multi-variant enum, or generator, or so.
392 // Treat this like a union: without reading from memory,
393 // we cannot determine the variant we are in. Reading from
394 // memory would be subject to Stacked Borrows rules, leading
395 // to all sorts of "funny" recursion.
396 // We only end up here if the type is *not* freeze, so we just call the
397 // `UnsafeCell` action.
398 (self.unsafe_cell_action)(v)
400 Variants::Single { .. } => {
401 // Proceed further, try to find where exactly that `UnsafeCell`
409 // Make sure we visit aggregrates in increasing offset order.
412 place: &MPlaceTy<'tcx, Tag>,
413 fields: impl Iterator<Item = InterpResult<'tcx, MPlaceTy<'tcx, Tag>>>,
414 ) -> InterpResult<'tcx> {
415 match place.layout.fields {
416 FieldsShape::Array { .. } => {
417 // For the array layout, we know the iterator will yield sorted elements so
418 // we can avoid the allocation.
419 self.walk_aggregate(place, fields)
421 FieldsShape::Arbitrary { .. } => {
422 // Gather the subplaces and sort them before visiting.
424 fields.collect::<InterpResult<'tcx, Vec<MPlaceTy<'tcx, Tag>>>>()?;
425 // we just compare offsets, the abs. value never matters
426 places.sort_by_key(|place| place.ptr.addr());
427 self.walk_aggregate(place, places.into_iter().map(Ok))
429 FieldsShape::Union { .. } | FieldsShape::Primitive => {
431 bug!("unions/primitives are not aggregates we should ever visit")
438 _v: &MPlaceTy<'tcx, Tag>,
439 _fields: NonZeroUsize,
440 ) -> InterpResult<'tcx> {
441 bug!("we should have already handled unions in `visit_value`")
446 /// Helper function used inside the shims of foreign functions to check that isolation is
447 /// disabled. It returns an error using the `name` of the foreign function if this is not the
449 fn check_no_isolation(&self, name: &str) -> InterpResult<'tcx> {
450 if !self.eval_context_ref().machine.communicate() {
451 self.reject_in_isolation(name, RejectOpWith::Abort)?;
456 /// Helper function used inside the shims of foreign functions which reject the op
457 /// when isolation is enabled. It is used to print a warning/backtrace about the rejection.
458 fn reject_in_isolation(&self, op_name: &str, reject_with: RejectOpWith) -> InterpResult<'tcx> {
459 let this = self.eval_context_ref();
461 RejectOpWith::Abort => isolation_abort_error(op_name),
462 RejectOpWith::WarningWithoutBacktrace => {
465 .warn(&format!("{} was made to return an error due to isolation", op_name));
468 RejectOpWith::Warning => {
469 register_diagnostic(NonHaltingDiagnostic::RejectedIsolatedOp(op_name.to_string()));
472 RejectOpWith::NoWarning => Ok(()), // no warning
476 /// Helper function used inside the shims of foreign functions to assert that the target OS
477 /// is `target_os`. It panics showing a message with the `name` of the foreign function
478 /// if this is not the case.
479 fn assert_target_os(&self, target_os: &str, name: &str) {
481 self.eval_context_ref().tcx.sess.target.os,
483 "`{}` is only available on the `{}` target OS",
489 /// Get last error variable as a place, lazily allocating thread-local storage for it if
491 fn last_error_place(&mut self) -> InterpResult<'tcx, MPlaceTy<'tcx, Tag>> {
492 let this = self.eval_context_mut();
493 if let Some(errno_place) = this.active_thread_ref().last_error {
496 // Allocate new place, set initial value to 0.
497 let errno_layout = this.machine.layouts.u32;
498 let errno_place = this.allocate(errno_layout, MiriMemoryKind::Machine.into())?;
499 this.write_scalar(Scalar::from_u32(0), &errno_place.into())?;
500 this.active_thread_mut().last_error = Some(errno_place);
505 /// Sets the last error variable.
506 fn set_last_error(&mut self, scalar: Scalar<Tag>) -> InterpResult<'tcx> {
507 let this = self.eval_context_mut();
508 let errno_place = this.last_error_place()?;
509 this.write_scalar(scalar, &errno_place.into())
512 /// Gets the last error variable.
513 fn get_last_error(&mut self) -> InterpResult<'tcx, Scalar<Tag>> {
514 let this = self.eval_context_mut();
515 let errno_place = this.last_error_place()?;
516 this.read_scalar(&errno_place.into())?.check_init()
519 /// This function tries to produce the most similar OS error from the `std::io::ErrorKind`
520 /// as a platform-specific errnum.
521 fn io_error_to_errnum(&self, err_kind: std::io::ErrorKind) -> InterpResult<'tcx, Scalar<Tag>> {
522 let this = self.eval_context_ref();
523 let target = &this.tcx.sess.target;
524 if target.families.iter().any(|f| f == "unix") {
525 for &(kind, name) in UNIX_IO_ERROR_TABLE {
526 if err_kind == kind {
527 return this.eval_libc(name);
530 throw_unsup_format!("io error {:?} cannot be translated into a raw os error", err_kind)
531 } else if target.families.iter().any(|f| f == "windows") {
532 // FIXME: we have to finish implementing the Windows equivalent of this.
533 use std::io::ErrorKind::*;
537 NotFound => "ERROR_FILE_NOT_FOUND",
538 PermissionDenied => "ERROR_ACCESS_DENIED",
541 "io error {:?} cannot be translated into a raw os error",
548 "converting io::Error into errnum is unsupported for OS {}",
554 /// The inverse of `io_error_to_errnum`.
555 fn errnum_to_io_error(&self, errnum: Scalar<Tag>) -> InterpResult<'tcx, std::io::ErrorKind> {
556 let this = self.eval_context_ref();
557 let target = &this.tcx.sess.target;
558 if target.families.iter().any(|f| f == "unix") {
559 let errnum = errnum.to_i32()?;
560 for &(kind, name) in UNIX_IO_ERROR_TABLE {
561 if errnum == this.eval_libc_i32(name)? {
565 throw_unsup_format!("raw errnum {:?} cannot be translated into io::Error", errnum)
568 "converting errnum into io::Error is unsupported for OS {}",
574 /// Sets the last OS error using a `std::io::ErrorKind`.
575 fn set_last_error_from_io_error(&mut self, err_kind: std::io::ErrorKind) -> InterpResult<'tcx> {
576 self.set_last_error(self.io_error_to_errnum(err_kind)?)
579 /// Helper function that consumes an `std::io::Result<T>` and returns an
580 /// `InterpResult<'tcx,T>::Ok` instead. In case the result is an error, this function returns
581 /// `Ok(-1)` and sets the last OS error accordingly.
583 /// This function uses `T: From<i32>` instead of `i32` directly because some IO related
584 /// functions return different integer types (like `read`, that returns an `i64`).
585 fn try_unwrap_io_result<T: From<i32>>(
587 result: std::io::Result<T>,
588 ) -> InterpResult<'tcx, T> {
592 self.eval_context_mut().set_last_error_from_io_error(e.kind())?;
598 fn read_scalar_at_offset(
600 op: &OpTy<'tcx, Tag>,
602 layout: TyAndLayout<'tcx>,
603 ) -> InterpResult<'tcx, ScalarMaybeUninit<Tag>> {
604 let this = self.eval_context_ref();
605 let op_place = this.deref_operand(op)?;
606 let offset = Size::from_bytes(offset);
607 // Ensure that the following read at an offset is within bounds
608 assert!(op_place.layout.size >= offset + layout.size);
609 let value_place = op_place.offset(offset, MemPlaceMeta::None, layout, this)?;
610 this.read_scalar(&value_place.into())
613 fn write_scalar_at_offset(
615 op: &OpTy<'tcx, Tag>,
617 value: impl Into<ScalarMaybeUninit<Tag>>,
618 layout: TyAndLayout<'tcx>,
619 ) -> InterpResult<'tcx, ()> {
620 let this = self.eval_context_mut();
621 let op_place = this.deref_operand(op)?;
622 let offset = Size::from_bytes(offset);
623 // Ensure that the following read at an offset is within bounds
624 assert!(op_place.layout.size >= offset + layout.size);
625 let value_place = op_place.offset(offset, MemPlaceMeta::None, layout, this)?;
626 this.write_scalar(value, &value_place.into())
629 /// Parse a `timespec` struct and return it as a `std::time::Duration`. It returns `None`
630 /// if the value in the `timespec` struct is invalid. Some libc functions will return
631 /// `EINVAL` in this case.
632 fn read_timespec(&mut self, tp: &MPlaceTy<'tcx, Tag>) -> InterpResult<'tcx, Option<Duration>> {
633 let this = self.eval_context_mut();
634 let seconds_place = this.mplace_field(tp, 0)?;
635 let seconds_scalar = this.read_scalar(&seconds_place.into())?;
636 let seconds = seconds_scalar.to_machine_isize(this)?;
637 let nanoseconds_place = this.mplace_field(tp, 1)?;
638 let nanoseconds_scalar = this.read_scalar(&nanoseconds_place.into())?;
639 let nanoseconds = nanoseconds_scalar.to_machine_isize(this)?;
642 // tv_sec must be non-negative.
643 let seconds: u64 = seconds.try_into().ok()?;
644 // tv_nsec must be non-negative.
645 let nanoseconds: u32 = nanoseconds.try_into().ok()?;
646 if nanoseconds >= 1_000_000_000 {
647 // tv_nsec must not be greater than 999,999,999.
650 Duration::new(seconds, nanoseconds)
654 fn read_c_str<'a>(&'a self, ptr: Pointer<Option<Tag>>) -> InterpResult<'tcx, &'a [u8]>
659 let this = self.eval_context_ref();
660 let size1 = Size::from_bytes(1);
662 // Step 1: determine the length.
663 let mut len = Size::ZERO;
665 // FIXME: We are re-getting the allocation each time around the loop.
666 // Would be nice if we could somehow "extend" an existing AllocRange.
668 this.get_ptr_alloc(ptr.offset(len, this)?.into(), size1, Align::ONE)?.unwrap(); // not a ZST, so we will get a result
669 let byte = alloc.read_scalar(alloc_range(Size::ZERO, size1))?.to_u8()?;
677 // Step 2: get the bytes.
678 this.read_bytes_ptr(ptr.into(), len)
681 fn read_wide_str(&self, mut ptr: Pointer<Option<Tag>>) -> InterpResult<'tcx, Vec<u16>> {
682 let this = self.eval_context_ref();
683 let size2 = Size::from_bytes(2);
684 let align2 = Align::from_bytes(2).unwrap();
686 let mut wchars = Vec::new();
688 // FIXME: We are re-getting the allocation each time around the loop.
689 // Would be nice if we could somehow "extend" an existing AllocRange.
690 let alloc = this.get_ptr_alloc(ptr.into(), size2, align2)?.unwrap(); // not a ZST, so we will get a result
691 let wchar = alloc.read_scalar(alloc_range(Size::ZERO, size2))?.to_u16()?;
696 ptr = ptr.offset(size2, this)?;
703 /// Check that the ABI is what we expect.
704 fn check_abi<'a>(&self, abi: Abi, exp_abi: Abi) -> InterpResult<'a, ()> {
705 if self.eval_context_ref().machine.enforce_abi && abi != exp_abi {
707 "calling a function with ABI {} using caller ABI {}",
715 fn frame_in_std(&self) -> bool {
716 let this = self.eval_context_ref();
717 this.tcx.lang_items().start_fn().map_or(false, |start_fn| {
718 this.tcx.def_path(this.frame().instance.def_id()).krate
719 == this.tcx.def_path(start_fn).krate
723 /// Handler that should be called when unsupported functionality is encountered.
724 /// This function will either panic within the context of the emulated application
725 /// or return an error in the Miri process context
727 /// Return value of `Ok(bool)` indicates whether execution should continue.
728 fn handle_unsupported<S: AsRef<str>>(&mut self, error_msg: S) -> InterpResult<'tcx, ()> {
729 let this = self.eval_context_mut();
730 if this.machine.panic_on_unsupported {
731 // message is slightly different here to make automated analysis easier
732 let error_msg = format!("unsupported Miri functionality: {}", error_msg.as_ref());
733 this.start_panic(error_msg.as_ref(), StackPopUnwind::Skip)?;
736 throw_unsup_format!("{}", error_msg.as_ref());
740 fn check_abi_and_shim_symbol_clash(
745 ) -> InterpResult<'tcx, ()> {
746 self.check_abi(abi, exp_abi)?;
747 if let Some((body, _)) = self.eval_context_mut().lookup_exported_symbol(link_name)? {
748 throw_machine_stop!(TerminationInfo::SymbolShimClashing {
750 span: body.span.data(),
756 fn check_shim<'a, const N: usize>(
761 args: &'a [OpTy<'tcx, Tag>],
762 ) -> InterpResult<'tcx, &'a [OpTy<'tcx, Tag>; N]>
764 &'a [OpTy<'tcx, Tag>; N]: TryFrom<&'a [OpTy<'tcx, Tag>]>,
766 self.check_abi_and_shim_symbol_clash(abi, exp_abi, link_name)?;
767 check_arg_count(args)
770 /// Mark a machine allocation that was just created as immutable.
771 fn mark_immutable(&mut self, mplace: &MemPlace<Tag>) {
772 let this = self.eval_context_mut();
773 // This got just allocated, so there definitely is a pointer here.
774 this.alloc_mark_immutable(mplace.ptr.into_pointer_or_addr().unwrap().provenance.alloc_id)
779 /// Check that the number of args is what we expect.
780 pub fn check_arg_count<'a, 'tcx, const N: usize>(
781 args: &'a [OpTy<'tcx, Tag>],
782 ) -> InterpResult<'tcx, &'a [OpTy<'tcx, Tag>; N]>
784 &'a [OpTy<'tcx, Tag>; N]: TryFrom<&'a [OpTy<'tcx, Tag>]>,
786 if let Ok(ops) = args.try_into() {
789 throw_ub_format!("incorrect number of arguments: got {}, expected {}", args.len(), N)
792 pub fn isolation_abort_error(name: &str) -> InterpResult<'static> {
793 throw_machine_stop!(TerminationInfo::UnsupportedInIsolation(format!(
794 "{} not available when isolation is enabled",
799 /// Retrieve the list of local crates that should have been passed by cargo-miri in
800 /// MIRI_LOCAL_CRATES and turn them into `CrateNum`s.
801 pub fn get_local_crates(tcx: &TyCtxt<'_>) -> Vec<CrateNum> {
802 // Convert the local crate names from the passed-in config into CrateNums so that they can
803 // be looked up quickly during execution
804 let local_crate_names = std::env::var("MIRI_LOCAL_CRATES")
805 .map(|crates| crates.split(",").map(|krate| krate.to_string()).collect::<Vec<_>>())
806 .unwrap_or_default();
807 let mut local_crates = Vec::new();
808 for &crate_num in tcx.crates(()) {
809 let name = tcx.crate_name(crate_num);
810 let name = name.as_str();
811 if local_crate_names.iter().any(|local_name| local_name == name) {
812 local_crates.push(crate_num);