4 use std::num::NonZeroUsize;
5 use std::time::Duration;
9 use rustc_hir::def_id::{DefId, CRATE_DEF_INDEX};
10 use rustc_middle::mir;
11 use rustc_middle::ty::{
13 layout::{LayoutOf, TyAndLayout},
16 use rustc_span::{def_id::CrateNum, Symbol};
17 use rustc_target::abi::{Align, FieldsShape, Size, Variants};
18 use rustc_target::spec::abi::Abi;
24 impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
26 const UNIX_IO_ERROR_TABLE: &[(std::io::ErrorKind, &str)] = {
27 use std::io::ErrorKind::*;
29 (ConnectionRefused, "ECONNREFUSED"),
30 (ConnectionReset, "ECONNRESET"),
31 (PermissionDenied, "EPERM"),
32 (BrokenPipe, "EPIPE"),
33 (NotConnected, "ENOTCONN"),
34 (ConnectionAborted, "ECONNABORTED"),
35 (AddrNotAvailable, "EADDRNOTAVAIL"),
36 (AddrInUse, "EADDRINUSE"),
38 (Interrupted, "EINTR"),
39 (InvalidInput, "EINVAL"),
40 (TimedOut, "ETIMEDOUT"),
41 (AlreadyExists, "EEXIST"),
42 (WouldBlock, "EWOULDBLOCK"),
43 (DirectoryNotEmpty, "ENOTEMPTY"),
47 /// Gets an instance for a path.
48 fn try_resolve_did<'tcx>(tcx: TyCtxt<'tcx>, path: &[&str]) -> Option<DefId> {
49 tcx.crates(()).iter().find(|&&krate| tcx.crate_name(krate).as_str() == path[0]).and_then(
51 let krate = DefId { krate: *krate, index: CRATE_DEF_INDEX };
52 let mut items = tcx.module_children(krate);
53 let mut path_it = path.iter().skip(1).peekable();
55 while let Some(segment) = path_it.next() {
56 for item in mem::take(&mut items).iter() {
57 if item.ident.name.as_str() == *segment {
58 if path_it.peek().is_none() {
59 return Some(item.res.def_id());
62 items = tcx.module_children(item.res.def_id());
72 pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
73 /// Gets an instance for a path.
74 fn resolve_path(&self, path: &[&str]) -> ty::Instance<'tcx> {
75 let did = try_resolve_did(self.eval_context_ref().tcx.tcx, path)
76 .unwrap_or_else(|| panic!("failed to find required Rust item: {:?}", path));
77 ty::Instance::mono(self.eval_context_ref().tcx.tcx, did)
80 /// Evaluates the scalar at the specified path. Returns Some(val)
81 /// if the path could be resolved, and None otherwise
82 fn eval_path_scalar(&self, path: &[&str]) -> InterpResult<'tcx, Scalar<Tag>> {
83 let this = self.eval_context_ref();
84 let instance = this.resolve_path(path);
85 let cid = GlobalId { instance, promoted: None };
86 let const_val = this.eval_to_allocation(cid)?;
87 let const_val = this.read_scalar(&const_val.into())?;
88 const_val.check_init()
91 /// Helper function to get a `libc` constant as a `Scalar`.
92 fn eval_libc(&self, name: &str) -> InterpResult<'tcx, Scalar<Tag>> {
93 self.eval_path_scalar(&["libc", name])
96 /// Helper function to get a `libc` constant as an `i32`.
97 fn eval_libc_i32(&self, name: &str) -> InterpResult<'tcx, i32> {
98 // TODO: Cache the result.
99 self.eval_libc(name)?.to_i32()
102 /// Helper function to get a `windows` constant as a `Scalar`.
103 fn eval_windows(&self, module: &str, name: &str) -> InterpResult<'tcx, Scalar<Tag>> {
104 self.eval_context_ref().eval_path_scalar(&["std", "sys", "windows", module, name])
107 /// Helper function to get a `windows` constant as a `u64`.
108 fn eval_windows_u64(&self, module: &str, name: &str) -> InterpResult<'tcx, u64> {
109 // TODO: Cache the result.
110 self.eval_windows(module, name)?.to_u64()
113 /// Helper function to get the `TyAndLayout` of a `libc` type
114 fn libc_ty_layout(&self, name: &str) -> InterpResult<'tcx, TyAndLayout<'tcx>> {
115 let this = self.eval_context_ref();
116 let ty = this.resolve_path(&["libc", name]).ty(*this.tcx, ty::ParamEnv::reveal_all());
120 /// Helper function to get the `TyAndLayout` of a `windows` type
121 fn windows_ty_layout(&self, name: &str) -> InterpResult<'tcx, TyAndLayout<'tcx>> {
122 let this = self.eval_context_ref();
124 .resolve_path(&["std", "sys", "windows", "c", name])
125 .ty(*this.tcx, ty::ParamEnv::reveal_all());
129 /// Project to the given *named* field of the mplace (which must be a struct or union type).
130 fn mplace_field_named(
132 mplace: &MPlaceTy<'tcx, Tag>,
134 ) -> InterpResult<'tcx, MPlaceTy<'tcx, Tag>> {
135 let this = self.eval_context_ref();
136 let adt = mplace.layout.ty.ty_adt_def().unwrap();
137 for (idx, field) in adt.non_enum_variant().fields.iter().enumerate() {
138 if field.name.as_str() == name {
139 return this.mplace_field(mplace, idx);
142 bug!("No field named {} in type {}", name, mplace.layout.ty);
145 /// Write an int of the appropriate size to `dest`. The target type may be signed or unsigned,
146 /// we try to do the right thing anyway. `i128` can fit all integer types except for `u128` so
147 /// this method is fine for almost all integer types.
148 fn write_int(&mut self, i: impl Into<i128>, dest: &PlaceTy<'tcx, Tag>) -> InterpResult<'tcx> {
149 assert!(dest.layout.abi.is_scalar(), "write_int on non-scalar type {}", dest.layout.ty);
150 let val = if dest.layout.abi.is_signed() {
151 Scalar::from_int(i, dest.layout.size)
153 Scalar::from_uint(u64::try_from(i.into()).unwrap(), dest.layout.size)
155 self.eval_context_mut().write_scalar(val, dest)
158 /// Write the first N fields of the given place.
162 dest: &MPlaceTy<'tcx, Tag>,
163 ) -> InterpResult<'tcx> {
164 let this = self.eval_context_mut();
165 for (idx, &val) in values.iter().enumerate() {
166 let field = this.mplace_field(dest, idx)?;
167 this.write_int(val, &field.into())?;
172 /// Write the given fields of the given place.
173 fn write_int_fields_named(
175 values: &[(&str, i128)],
176 dest: &MPlaceTy<'tcx, Tag>,
177 ) -> InterpResult<'tcx> {
178 let this = self.eval_context_mut();
179 for &(name, val) in values.iter() {
180 let field = this.mplace_field_named(dest, name)?;
181 this.write_int(val, &field.into())?;
186 /// Write a 0 of the appropriate size to `dest`.
187 fn write_null(&mut self, dest: &PlaceTy<'tcx, Tag>) -> InterpResult<'tcx> {
188 self.write_int(0, dest)
191 /// Test if this pointer equals 0.
192 fn ptr_is_null(&self, ptr: Pointer<Option<Tag>>) -> InterpResult<'tcx, bool> {
193 let this = self.eval_context_ref();
194 let null = Scalar::null_ptr(this);
195 this.ptr_eq(Scalar::from_maybe_pointer(ptr, this), null)
198 /// Get the `Place` for a local
199 fn local_place(&mut self, local: mir::Local) -> InterpResult<'tcx, PlaceTy<'tcx, Tag>> {
200 let this = self.eval_context_mut();
201 let place = mir::Place { local, projection: List::empty() };
202 this.eval_place(place)
205 /// Generate some random bytes, and write them to `dest`.
206 fn gen_random(&mut self, ptr: Pointer<Option<Tag>>, len: u64) -> InterpResult<'tcx> {
207 // Some programs pass in a null pointer and a length of 0
208 // to their platform's random-generation function (e.g. getrandom())
209 // on Linux. For compatibility with these programs, we don't perform
210 // any additional checks - it's okay if the pointer is invalid,
211 // since we wouldn't actually be writing to it.
215 let this = self.eval_context_mut();
217 let mut data = vec![0; usize::try_from(len).unwrap()];
219 if this.machine.communicate() {
220 // Fill the buffer using the host's rng.
221 getrandom::getrandom(&mut data)
222 .map_err(|err| err_unsup_format!("host getrandom failed: {}", err))?;
224 let rng = this.machine.rng.get_mut();
225 rng.fill_bytes(&mut data);
228 this.write_bytes_ptr(ptr, data.iter().copied())
231 /// Call a function: Push the stack frame and pass the arguments.
232 /// For now, arguments must be scalars (so that the caller does not have to know the layout).
235 f: ty::Instance<'tcx>,
237 args: &[Immediate<Tag>],
238 dest: Option<&PlaceTy<'tcx, Tag>>,
239 stack_pop: StackPopCleanup,
240 ) -> InterpResult<'tcx> {
241 let this = self.eval_context_mut();
242 let param_env = ty::ParamEnv::reveal_all(); // in Miri this is always the param_env we use... and this.param_env is private.
243 let callee_abi = f.ty(*this.tcx, param_env).fn_sig(*this.tcx).abi();
244 if this.machine.enforce_abi && callee_abi != caller_abi {
246 "calling a function with ABI {} using caller ABI {}",
253 let mir = &*this.load_mir(f.def, None)?;
254 this.push_stack_frame(f, mir, dest, stack_pop)?;
256 // Initialize arguments.
257 let mut callee_args = this.frame().body.args_iter();
259 let callee_arg = this.local_place(
262 .ok_or_else(|| err_ub_format!("callee has fewer arguments than expected"))?,
264 this.write_immediate(*arg, &callee_arg)?;
266 if callee_args.next().is_some() {
267 throw_ub_format!("callee has more arguments than expected");
273 /// Visits the memory covered by `place`, sensitive to freezing: the 2nd parameter
274 /// of `action` will be true if this is frozen, false if this is in an `UnsafeCell`.
275 /// The range is relative to `place`.
276 fn visit_freeze_sensitive(
278 place: &MPlaceTy<'tcx, Tag>,
280 mut action: impl FnMut(AllocRange, bool) -> InterpResult<'tcx>,
281 ) -> InterpResult<'tcx> {
282 let this = self.eval_context_ref();
283 trace!("visit_frozen(place={:?}, size={:?})", *place, size);
286 this.size_and_align_of_mplace(place)?
287 .map(|(size, _)| size)
288 .unwrap_or_else(|| place.layout.size)
290 // Store how far we proceeded into the place so far. Everything to the left of
291 // this offset has already been handled, in the sense that the frozen parts
292 // have had `action` called on them.
293 let start_addr = place.ptr.addr();
294 let mut cur_addr = start_addr;
295 // Called when we detected an `UnsafeCell` at the given offset and size.
296 // Calls `action` and advances `cur_ptr`.
297 let mut unsafe_cell_action = |unsafe_cell_ptr: &Pointer<Option<Tag>>,
298 unsafe_cell_size: Size| {
299 // We assume that we are given the fields in increasing offset order,
300 // and nothing else changes.
301 let unsafe_cell_addr = unsafe_cell_ptr.addr();
302 assert!(unsafe_cell_addr >= cur_addr);
303 let frozen_size = unsafe_cell_addr - cur_addr;
304 // Everything between the cur_ptr and this `UnsafeCell` is frozen.
305 if frozen_size != Size::ZERO {
306 action(alloc_range(cur_addr - start_addr, frozen_size), /*frozen*/ true)?;
308 cur_addr += frozen_size;
309 // This `UnsafeCell` is NOT frozen.
310 if unsafe_cell_size != Size::ZERO {
312 alloc_range(cur_addr - start_addr, unsafe_cell_size),
316 cur_addr += unsafe_cell_size;
322 let mut visitor = UnsafeCellVisitor {
324 unsafe_cell_action: |place| {
325 trace!("unsafe_cell_action on {:?}", place.ptr);
326 // We need a size to go on.
327 let unsafe_cell_size = this
328 .size_and_align_of_mplace(place)?
329 .map(|(size, _)| size)
330 // for extern types, just cover what we can
331 .unwrap_or_else(|| place.layout.size);
332 // Now handle this `UnsafeCell`, unless it is empty.
333 if unsafe_cell_size != Size::ZERO {
334 unsafe_cell_action(&place.ptr, unsafe_cell_size)
340 visitor.visit_value(place)?;
342 // The part between the end_ptr and the end of the place is also frozen.
343 // So pretend there is a 0-sized `UnsafeCell` at the end.
344 unsafe_cell_action(&place.ptr.offset(size, this)?, Size::ZERO)?;
348 /// Visiting the memory covered by a `MemPlace`, being aware of
349 /// whether we are inside an `UnsafeCell` or not.
350 struct UnsafeCellVisitor<'ecx, 'mir, 'tcx, F>
352 F: FnMut(&MPlaceTy<'tcx, Tag>) -> InterpResult<'tcx>,
354 ecx: &'ecx MiriEvalContext<'mir, 'tcx>,
355 unsafe_cell_action: F,
358 impl<'ecx, 'mir, 'tcx: 'mir, F> ValueVisitor<'mir, 'tcx, Evaluator<'mir, 'tcx>>
359 for UnsafeCellVisitor<'ecx, 'mir, 'tcx, F>
361 F: FnMut(&MPlaceTy<'tcx, Tag>) -> InterpResult<'tcx>,
363 type V = MPlaceTy<'tcx, Tag>;
366 fn ecx(&self) -> &MiriEvalContext<'mir, 'tcx> {
370 // Hook to detect `UnsafeCell`.
371 fn visit_value(&mut self, v: &MPlaceTy<'tcx, Tag>) -> InterpResult<'tcx> {
372 trace!("UnsafeCellVisitor: {:?} {:?}", *v, v.layout.ty);
373 let is_unsafe_cell = match v.layout.ty.kind() {
375 Some(adt.did()) == self.ecx.tcx.lang_items().unsafe_cell_type(),
379 // We do not have to recurse further, this is an `UnsafeCell`.
380 (self.unsafe_cell_action)(v)
381 } else if self.ecx.type_is_freeze(v.layout.ty) {
382 // This is `Freeze`, there cannot be an `UnsafeCell`
384 } else if matches!(v.layout.fields, FieldsShape::Union(..)) {
385 // A (non-frozen) union. We fall back to whatever the type says.
386 (self.unsafe_cell_action)(v)
388 // We want to not actually read from memory for this visit. So, before
389 // walking this value, we have to make sure it is not a
390 // `Variants::Multiple`.
391 match v.layout.variants {
392 Variants::Multiple { .. } => {
393 // A multi-variant enum, or generator, or so.
394 // Treat this like a union: without reading from memory,
395 // we cannot determine the variant we are in. Reading from
396 // memory would be subject to Stacked Borrows rules, leading
397 // to all sorts of "funny" recursion.
398 // We only end up here if the type is *not* freeze, so we just call the
399 // `UnsafeCell` action.
400 (self.unsafe_cell_action)(v)
402 Variants::Single { .. } => {
403 // Proceed further, try to find where exactly that `UnsafeCell`
411 // Make sure we visit aggregrates in increasing offset order.
414 place: &MPlaceTy<'tcx, Tag>,
415 fields: impl Iterator<Item = InterpResult<'tcx, MPlaceTy<'tcx, Tag>>>,
416 ) -> InterpResult<'tcx> {
417 match place.layout.fields {
418 FieldsShape::Array { .. } => {
419 // For the array layout, we know the iterator will yield sorted elements so
420 // we can avoid the allocation.
421 self.walk_aggregate(place, fields)
423 FieldsShape::Arbitrary { .. } => {
424 // Gather the subplaces and sort them before visiting.
426 fields.collect::<InterpResult<'tcx, Vec<MPlaceTy<'tcx, Tag>>>>()?;
427 // we just compare offsets, the abs. value never matters
428 places.sort_by_key(|place| place.ptr.addr());
429 self.walk_aggregate(place, places.into_iter().map(Ok))
431 FieldsShape::Union { .. } | FieldsShape::Primitive => {
433 bug!("unions/primitives are not aggregates we should ever visit")
440 _v: &MPlaceTy<'tcx, Tag>,
441 _fields: NonZeroUsize,
442 ) -> InterpResult<'tcx> {
443 bug!("we should have already handled unions in `visit_value`")
448 /// Helper function used inside the shims of foreign functions to check that isolation is
449 /// disabled. It returns an error using the `name` of the foreign function if this is not the
451 fn check_no_isolation(&self, name: &str) -> InterpResult<'tcx> {
452 if !self.eval_context_ref().machine.communicate() {
453 self.reject_in_isolation(name, RejectOpWith::Abort)?;
458 /// Helper function used inside the shims of foreign functions which reject the op
459 /// when isolation is enabled. It is used to print a warning/backtrace about the rejection.
460 fn reject_in_isolation(&self, op_name: &str, reject_with: RejectOpWith) -> InterpResult<'tcx> {
461 let this = self.eval_context_ref();
463 RejectOpWith::Abort => isolation_abort_error(op_name),
464 RejectOpWith::WarningWithoutBacktrace => {
467 .warn(&format!("{} was made to return an error due to isolation", op_name));
470 RejectOpWith::Warning => {
471 register_diagnostic(NonHaltingDiagnostic::RejectedIsolatedOp(op_name.to_string()));
474 RejectOpWith::NoWarning => Ok(()), // no warning
478 /// Helper function used inside the shims of foreign functions to assert that the target OS
479 /// is `target_os`. It panics showing a message with the `name` of the foreign function
480 /// if this is not the case.
481 fn assert_target_os(&self, target_os: &str, name: &str) {
483 self.eval_context_ref().tcx.sess.target.os,
485 "`{}` is only available on the `{}` target OS",
491 /// Get last error variable as a place, lazily allocating thread-local storage for it if
493 fn last_error_place(&mut self) -> InterpResult<'tcx, MPlaceTy<'tcx, Tag>> {
494 let this = self.eval_context_mut();
495 if let Some(errno_place) = this.active_thread_ref().last_error {
498 // Allocate new place, set initial value to 0.
499 let errno_layout = this.machine.layouts.u32;
500 let errno_place = this.allocate(errno_layout, MiriMemoryKind::Machine.into())?;
501 this.write_scalar(Scalar::from_u32(0), &errno_place.into())?;
502 this.active_thread_mut().last_error = Some(errno_place);
507 /// Sets the last error variable.
508 fn set_last_error(&mut self, scalar: Scalar<Tag>) -> InterpResult<'tcx> {
509 let this = self.eval_context_mut();
510 let errno_place = this.last_error_place()?;
511 this.write_scalar(scalar, &errno_place.into())
514 /// Gets the last error variable.
515 fn get_last_error(&mut self) -> InterpResult<'tcx, Scalar<Tag>> {
516 let this = self.eval_context_mut();
517 let errno_place = this.last_error_place()?;
518 this.read_scalar(&errno_place.into())?.check_init()
521 /// This function tries to produce the most similar OS error from the `std::io::ErrorKind`
522 /// as a platform-specific errnum.
523 fn io_error_to_errnum(&self, err_kind: std::io::ErrorKind) -> InterpResult<'tcx, Scalar<Tag>> {
524 let this = self.eval_context_ref();
525 let target = &this.tcx.sess.target;
526 if target.families.iter().any(|f| f == "unix") {
527 for &(kind, name) in UNIX_IO_ERROR_TABLE {
528 if err_kind == kind {
529 return this.eval_libc(name);
532 throw_unsup_format!("io error {:?} cannot be translated into a raw os error", err_kind)
533 } else if target.families.iter().any(|f| f == "windows") {
534 // FIXME: we have to finish implementing the Windows equivalent of this.
535 use std::io::ErrorKind::*;
539 NotFound => "ERROR_FILE_NOT_FOUND",
540 PermissionDenied => "ERROR_ACCESS_DENIED",
543 "io error {:?} cannot be translated into a raw os error",
550 "converting io::Error into errnum is unsupported for OS {}",
556 /// The inverse of `io_error_to_errnum`.
557 fn errnum_to_io_error(&self, errnum: Scalar<Tag>) -> InterpResult<'tcx, std::io::ErrorKind> {
558 let this = self.eval_context_ref();
559 let target = &this.tcx.sess.target;
560 if target.families.iter().any(|f| f == "unix") {
561 let errnum = errnum.to_i32()?;
562 for &(kind, name) in UNIX_IO_ERROR_TABLE {
563 if errnum == this.eval_libc_i32(name)? {
567 throw_unsup_format!("raw errnum {:?} cannot be translated into io::Error", errnum)
570 "converting errnum into io::Error is unsupported for OS {}",
576 /// Sets the last OS error using a `std::io::ErrorKind`.
577 fn set_last_error_from_io_error(&mut self, err_kind: std::io::ErrorKind) -> InterpResult<'tcx> {
578 self.set_last_error(self.io_error_to_errnum(err_kind)?)
581 /// Helper function that consumes an `std::io::Result<T>` and returns an
582 /// `InterpResult<'tcx,T>::Ok` instead. In case the result is an error, this function returns
583 /// `Ok(-1)` and sets the last OS error accordingly.
585 /// This function uses `T: From<i32>` instead of `i32` directly because some IO related
586 /// functions return different integer types (like `read`, that returns an `i64`).
587 fn try_unwrap_io_result<T: From<i32>>(
589 result: std::io::Result<T>,
590 ) -> InterpResult<'tcx, T> {
594 self.eval_context_mut().set_last_error_from_io_error(e.kind())?;
600 fn read_scalar_at_offset(
602 op: &OpTy<'tcx, Tag>,
604 layout: TyAndLayout<'tcx>,
605 ) -> InterpResult<'tcx, ScalarMaybeUninit<Tag>> {
606 let this = self.eval_context_ref();
607 let op_place = this.deref_operand(op)?;
608 let offset = Size::from_bytes(offset);
609 // Ensure that the following read at an offset is within bounds
610 assert!(op_place.layout.size >= offset + layout.size);
611 let value_place = op_place.offset(offset, MemPlaceMeta::None, layout, this)?;
612 this.read_scalar(&value_place.into())
615 fn write_scalar_at_offset(
617 op: &OpTy<'tcx, Tag>,
619 value: impl Into<ScalarMaybeUninit<Tag>>,
620 layout: TyAndLayout<'tcx>,
621 ) -> InterpResult<'tcx, ()> {
622 let this = self.eval_context_mut();
623 let op_place = this.deref_operand(op)?;
624 let offset = Size::from_bytes(offset);
625 // Ensure that the following read at an offset is within bounds
626 assert!(op_place.layout.size >= offset + layout.size);
627 let value_place = op_place.offset(offset, MemPlaceMeta::None, layout, this)?;
628 this.write_scalar(value, &value_place.into())
631 /// Parse a `timespec` struct and return it as a `std::time::Duration`. It returns `None`
632 /// if the value in the `timespec` struct is invalid. Some libc functions will return
633 /// `EINVAL` in this case.
634 fn read_timespec(&mut self, tp: &MPlaceTy<'tcx, Tag>) -> InterpResult<'tcx, Option<Duration>> {
635 let this = self.eval_context_mut();
636 let seconds_place = this.mplace_field(tp, 0)?;
637 let seconds_scalar = this.read_scalar(&seconds_place.into())?;
638 let seconds = seconds_scalar.to_machine_isize(this)?;
639 let nanoseconds_place = this.mplace_field(tp, 1)?;
640 let nanoseconds_scalar = this.read_scalar(&nanoseconds_place.into())?;
641 let nanoseconds = nanoseconds_scalar.to_machine_isize(this)?;
644 // tv_sec must be non-negative.
645 let seconds: u64 = seconds.try_into().ok()?;
646 // tv_nsec must be non-negative.
647 let nanoseconds: u32 = nanoseconds.try_into().ok()?;
648 if nanoseconds >= 1_000_000_000 {
649 // tv_nsec must not be greater than 999,999,999.
652 Duration::new(seconds, nanoseconds)
656 fn read_c_str<'a>(&'a self, ptr: Pointer<Option<Tag>>) -> InterpResult<'tcx, &'a [u8]>
661 let this = self.eval_context_ref();
662 let size1 = Size::from_bytes(1);
664 // Step 1: determine the length.
665 let mut len = Size::ZERO;
667 // FIXME: We are re-getting the allocation each time around the loop.
668 // Would be nice if we could somehow "extend" an existing AllocRange.
669 let alloc = this.get_ptr_alloc(ptr.offset(len, this)?, size1, Align::ONE)?.unwrap(); // not a ZST, so we will get a result
670 let byte = alloc.read_scalar(alloc_range(Size::ZERO, size1))?.to_u8()?;
678 // Step 2: get the bytes.
679 this.read_bytes_ptr(ptr, len)
682 fn read_wide_str(&self, mut ptr: Pointer<Option<Tag>>) -> InterpResult<'tcx, Vec<u16>> {
683 let this = self.eval_context_ref();
684 let size2 = Size::from_bytes(2);
685 let align2 = Align::from_bytes(2).unwrap();
687 let mut wchars = Vec::new();
689 // FIXME: We are re-getting the allocation each time around the loop.
690 // Would be nice if we could somehow "extend" an existing AllocRange.
691 let alloc = this.get_ptr_alloc(ptr, size2, align2)?.unwrap(); // not a ZST, so we will get a result
692 let wchar = alloc.read_scalar(alloc_range(Size::ZERO, size2))?.to_u16()?;
697 ptr = ptr.offset(size2, this)?;
704 /// Check that the ABI is what we expect.
705 fn check_abi<'a>(&self, abi: Abi, exp_abi: Abi) -> InterpResult<'a, ()> {
706 if self.eval_context_ref().machine.enforce_abi && abi != exp_abi {
708 "calling a function with ABI {} using caller ABI {}",
716 fn frame_in_std(&self) -> bool {
717 let this = self.eval_context_ref();
718 this.tcx.lang_items().start_fn().map_or(false, |start_fn| {
719 this.tcx.def_path(this.frame().instance.def_id()).krate
720 == this.tcx.def_path(start_fn).krate
724 /// Handler that should be called when unsupported functionality is encountered.
725 /// This function will either panic within the context of the emulated application
726 /// or return an error in the Miri process context
728 /// Return value of `Ok(bool)` indicates whether execution should continue.
729 fn handle_unsupported<S: AsRef<str>>(&mut self, error_msg: S) -> InterpResult<'tcx, ()> {
730 let this = self.eval_context_mut();
731 if this.machine.panic_on_unsupported {
732 // message is slightly different here to make automated analysis easier
733 let error_msg = format!("unsupported Miri functionality: {}", error_msg.as_ref());
734 this.start_panic(error_msg.as_ref(), StackPopUnwind::Skip)?;
737 throw_unsup_format!("{}", error_msg.as_ref());
741 fn check_abi_and_shim_symbol_clash(
746 ) -> InterpResult<'tcx, ()> {
747 self.check_abi(abi, exp_abi)?;
748 if let Some((body, _)) = self.eval_context_mut().lookup_exported_symbol(link_name)? {
749 throw_machine_stop!(TerminationInfo::SymbolShimClashing {
751 span: body.span.data(),
757 fn check_shim<'a, const N: usize>(
762 args: &'a [OpTy<'tcx, Tag>],
763 ) -> InterpResult<'tcx, &'a [OpTy<'tcx, Tag>; N]>
765 &'a [OpTy<'tcx, Tag>; N]: TryFrom<&'a [OpTy<'tcx, Tag>]>,
767 self.check_abi_and_shim_symbol_clash(abi, exp_abi, link_name)?;
768 check_arg_count(args)
771 /// Mark a machine allocation that was just created as immutable.
772 fn mark_immutable(&mut self, mplace: &MemPlace<Tag>) {
773 let this = self.eval_context_mut();
774 // This got just allocated, so there definitely is a pointer here.
775 this.alloc_mark_immutable(mplace.ptr.into_pointer_or_addr().unwrap().provenance.alloc_id)
780 /// Check that the number of args is what we expect.
781 pub fn check_arg_count<'a, 'tcx, const N: usize>(
782 args: &'a [OpTy<'tcx, Tag>],
783 ) -> InterpResult<'tcx, &'a [OpTy<'tcx, Tag>; N]>
785 &'a [OpTy<'tcx, Tag>; N]: TryFrom<&'a [OpTy<'tcx, Tag>]>,
787 if let Ok(ops) = args.try_into() {
790 throw_ub_format!("incorrect number of arguments: got {}, expected {}", args.len(), N)
793 pub fn isolation_abort_error(name: &str) -> InterpResult<'static> {
794 throw_machine_stop!(TerminationInfo::UnsupportedInIsolation(format!(
795 "{} not available when isolation is enabled",
800 /// Retrieve the list of local crates that should have been passed by cargo-miri in
801 /// MIRI_LOCAL_CRATES and turn them into `CrateNum`s.
802 pub fn get_local_crates(tcx: &TyCtxt<'_>) -> Vec<CrateNum> {
803 // Convert the local crate names from the passed-in config into CrateNums so that they can
804 // be looked up quickly during execution
805 let local_crate_names = std::env::var("MIRI_LOCAL_CRATES")
806 .map(|crates| crates.split(',').map(|krate| krate.to_string()).collect::<Vec<_>>())
807 .unwrap_or_default();
808 let mut local_crates = Vec::new();
809 for &crate_num in tcx.crates(()) {
810 let name = tcx.crate_name(crate_num);
811 let name = name.as_str();
812 if local_crate_names.iter().any(|local_name| local_name == name) {
813 local_crates.push(crate_num);