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Commit | Line | Data |
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1b1a35ee | 1 | use super::{AllocId, ConstAlloc, Pointer, Scalar}; |
ea8adc8c | 2 | |
74b04a01 | 3 | use crate::mir::interpret::ConstValue; |
3dfed10e | 4 | use crate::ty::{layout, query::TyCtxtAt, tls, FnSig, Ty}; |
ea8adc8c | 5 | |
ba9703b0 | 6 | use rustc_data_structures::sync::Lock; |
f9f354fc | 7 | use rustc_errors::{pluralize, struct_span_err, DiagnosticBuilder, ErrorReported}; |
e1599b0c | 8 | use rustc_macros::HashStable; |
ba9703b0 | 9 | use rustc_session::CtfeBacktrace; |
3dfed10e | 10 | use rustc_span::def_id::DefId; |
ba9703b0 | 11 | use rustc_target::abi::{Align, Size}; |
f9f354fc | 12 | use std::{any::Any, backtrace::Backtrace, fmt, mem}; |
e1599b0c | 13 | |
3dfed10e | 14 | #[derive(Debug, Copy, Clone, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)] |
a1dfa0c6 | 15 | pub enum ErrorHandled { |
ba9703b0 XL |
16 | /// Already reported an error for this evaluation, and the compilation is |
17 | /// *guaranteed* to fail. Warnings/lints *must not* produce `Reported`. | |
18 | Reported(ErrorReported), | |
19 | /// Already emitted a lint for this evaluation. | |
20 | Linted, | |
a1dfa0c6 XL |
21 | /// Don't emit an error, the evaluation failed because the MIR was generic |
22 | /// and the substs didn't fully monomorphize it. | |
23 | TooGeneric, | |
24 | } | |
25 | ||
1b1a35ee XL |
26 | impl From<ErrorReported> for ErrorHandled { |
27 | fn from(err: ErrorReported) -> ErrorHandled { | |
28 | ErrorHandled::Reported(err) | |
29 | } | |
30 | } | |
31 | ||
3dfed10e | 32 | CloneTypeFoldableAndLiftImpls! { |
dc9dc135 XL |
33 | ErrorHandled, |
34 | } | |
35 | ||
1b1a35ee XL |
36 | pub type EvalToAllocationRawResult<'tcx> = Result<ConstAlloc<'tcx>, ErrorHandled>; |
37 | pub type EvalToConstValueResult<'tcx> = Result<ConstValue<'tcx>, ErrorHandled>; | |
8faf50e0 | 38 | |
dc9dc135 | 39 | pub fn struct_error<'tcx>(tcx: TyCtxtAt<'tcx>, msg: &str) -> DiagnosticBuilder<'tcx> { |
8faf50e0 XL |
40 | struct_span_err!(tcx.sess, tcx.span, E0080, "{}", msg) |
41 | } | |
42 | ||
dc9dc135 | 43 | /// Packages the kind of error we got from the const code interpreter |
60c5eb7d | 44 | /// up with a Rust-level backtrace of where the error occurred. |
dc9dc135 | 45 | /// Thsese should always be constructed by calling `.into()` on |
416331ca XL |
46 | /// a `InterpError`. In `librustc_mir::interpret`, we have `throw_err_*` |
47 | /// macros for this. | |
60c5eb7d | 48 | #[derive(Debug)] |
dc9dc135 | 49 | pub struct InterpErrorInfo<'tcx> { |
416331ca | 50 | pub kind: InterpError<'tcx>, |
dc9dc135 | 51 | backtrace: Option<Box<Backtrace>>, |
a1dfa0c6 XL |
52 | } |
53 | ||
416331ca XL |
54 | impl fmt::Display for InterpErrorInfo<'_> { |
55 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { | |
56 | write!(f, "{}", self.kind) | |
57 | } | |
58 | } | |
59 | ||
60 | impl InterpErrorInfo<'_> { | |
f9f354fc XL |
61 | pub fn print_backtrace(&self) { |
62 | if let Some(backtrace) = self.backtrace.as_ref() { | |
63 | print_backtrace(backtrace); | |
a1dfa0c6 XL |
64 | } |
65 | } | |
66 | } | |
67 | ||
f9f354fc XL |
68 | fn print_backtrace(backtrace: &Backtrace) { |
69 | eprintln!("\n\nAn error occurred in miri:\n{}", backtrace); | |
ea8adc8c XL |
70 | } |
71 | ||
74b04a01 | 72 | impl From<ErrorHandled> for InterpErrorInfo<'_> { |
e1599b0c XL |
73 | fn from(err: ErrorHandled) -> Self { |
74 | match err { | |
ba9703b0 XL |
75 | ErrorHandled::Reported(ErrorReported) | ErrorHandled::Linted => { |
76 | err_inval!(ReferencedConstant) | |
77 | } | |
e1599b0c | 78 | ErrorHandled::TooGeneric => err_inval!(TooGeneric), |
dfeec247 XL |
79 | } |
80 | .into() | |
e1599b0c XL |
81 | } |
82 | } | |
83 | ||
29967ef6 XL |
84 | impl From<ErrorReported> for InterpErrorInfo<'_> { |
85 | fn from(err: ErrorReported) -> Self { | |
86 | InterpError::InvalidProgram(InvalidProgramInfo::AlreadyReported(err)).into() | |
87 | } | |
88 | } | |
89 | ||
416331ca XL |
90 | impl<'tcx> From<InterpError<'tcx>> for InterpErrorInfo<'tcx> { |
91 | fn from(kind: InterpError<'tcx>) -> Self { | |
3dfed10e XL |
92 | let capture_backtrace = tls::with_opt(|tcx| { |
93 | if let Some(tcx) = tcx { | |
94 | *Lock::borrow(&tcx.sess.ctfe_backtrace) | |
ba9703b0 XL |
95 | } else { |
96 | CtfeBacktrace::Disabled | |
97 | } | |
98 | }); | |
a1dfa0c6 | 99 | |
ba9703b0 XL |
100 | let backtrace = match capture_backtrace { |
101 | CtfeBacktrace::Disabled => None, | |
f9f354fc | 102 | CtfeBacktrace::Capture => Some(Box::new(Backtrace::force_capture())), |
ba9703b0 XL |
103 | CtfeBacktrace::Immediate => { |
104 | // Print it now. | |
f9f354fc XL |
105 | let backtrace = Backtrace::force_capture(); |
106 | print_backtrace(&backtrace); | |
ba9703b0 | 107 | None |
dfeec247 | 108 | } |
a1dfa0c6 | 109 | }; |
ba9703b0 | 110 | |
dfeec247 | 111 | InterpErrorInfo { kind, backtrace } |
ea8adc8c XL |
112 | } |
113 | } | |
114 | ||
e1599b0c XL |
115 | /// Error information for when the program we executed turned out not to actually be a valid |
116 | /// program. This cannot happen in stand-alone Miri, but it can happen during CTFE/ConstProp | |
117 | /// where we work on generic code or execution does not have all information available. | |
416331ca XL |
118 | pub enum InvalidProgramInfo<'tcx> { |
119 | /// Resolution can fail if we are in a too generic context. | |
120 | TooGeneric, | |
121 | /// Cannot compute this constant because it depends on another one | |
122 | /// which already produced an error. | |
123 | ReferencedConstant, | |
29967ef6 XL |
124 | /// Abort in case errors are already reported. |
125 | AlreadyReported(ErrorReported), | |
416331ca XL |
126 | /// An error occurred during layout computation. |
127 | Layout(layout::LayoutError<'tcx>), | |
ba9703b0 XL |
128 | /// An invalid transmute happened. |
129 | TransmuteSizeDiff(Ty<'tcx>, Ty<'tcx>), | |
416331ca | 130 | } |
b7449926 | 131 | |
f9f354fc | 132 | impl fmt::Display for InvalidProgramInfo<'_> { |
416331ca XL |
133 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
134 | use InvalidProgramInfo::*; | |
135 | match self { | |
dfeec247 XL |
136 | TooGeneric => write!(f, "encountered overly generic constant"), |
137 | ReferencedConstant => write!(f, "referenced constant has errors"), | |
29967ef6 | 138 | AlreadyReported(ErrorReported) => { |
ba9703b0 XL |
139 | write!(f, "encountered constants with type errors, stopping evaluation") |
140 | } | |
dfeec247 | 141 | Layout(ref err) => write!(f, "{}", err), |
ba9703b0 XL |
142 | TransmuteSizeDiff(from_ty, to_ty) => write!( |
143 | f, | |
144 | "transmuting `{}` to `{}` is not possible, because these types do not have the same size", | |
145 | from_ty, to_ty | |
146 | ), | |
416331ca XL |
147 | } |
148 | } | |
149 | } | |
150 | ||
f9f354fc | 151 | /// Details of why a pointer had to be in-bounds. |
3dfed10e | 152 | #[derive(Debug, Copy, Clone, TyEncodable, TyDecodable, HashStable)] |
f9f354fc XL |
153 | pub enum CheckInAllocMsg { |
154 | MemoryAccessTest, | |
155 | NullPointerTest, | |
156 | PointerArithmeticTest, | |
157 | InboundsTest, | |
158 | } | |
159 | ||
160 | impl fmt::Display for CheckInAllocMsg { | |
161 | /// When this is printed as an error the context looks like this | |
162 | /// "{test name} failed: pointer must be in-bounds at offset..." | |
163 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { | |
164 | write!( | |
165 | f, | |
166 | "{}", | |
167 | match *self { | |
168 | CheckInAllocMsg::MemoryAccessTest => "memory access", | |
169 | CheckInAllocMsg::NullPointerTest => "NULL pointer test", | |
170 | CheckInAllocMsg::PointerArithmeticTest => "pointer arithmetic", | |
171 | CheckInAllocMsg::InboundsTest => "inbounds test", | |
172 | } | |
173 | ) | |
174 | } | |
175 | } | |
176 | ||
177 | /// Details of an access to uninitialized bytes where it is not allowed. | |
178 | #[derive(Debug)] | |
179 | pub struct UninitBytesAccess { | |
180 | /// Location of the original memory access. | |
181 | pub access_ptr: Pointer, | |
182 | /// Size of the original memory access. | |
183 | pub access_size: Size, | |
184 | /// Location of the first uninitialized byte that was accessed. | |
185 | pub uninit_ptr: Pointer, | |
186 | /// Number of consecutive uninitialized bytes that were accessed. | |
187 | pub uninit_size: Size, | |
188 | } | |
189 | ||
e1599b0c | 190 | /// Error information for when the program caused Undefined Behavior. |
f9f354fc | 191 | pub enum UndefinedBehaviorInfo<'tcx> { |
416331ca XL |
192 | /// Free-form case. Only for errors that are never caught! |
193 | Ub(String), | |
416331ca XL |
194 | /// Unreachable code was executed. |
195 | Unreachable, | |
60c5eb7d | 196 | /// A slice/array index projection went out-of-bounds. |
ba9703b0 XL |
197 | BoundsCheckFailed { |
198 | len: u64, | |
199 | index: u64, | |
200 | }, | |
60c5eb7d XL |
201 | /// Something was divided by 0 (x / 0). |
202 | DivisionByZero, | |
203 | /// Something was "remainded" by 0 (x % 0). | |
204 | RemainderByZero, | |
205 | /// Overflowing inbounds pointer arithmetic. | |
206 | PointerArithOverflow, | |
74b04a01 XL |
207 | /// Invalid metadata in a wide pointer (using `str` to avoid allocations). |
208 | InvalidMeta(&'static str), | |
f9f354fc XL |
209 | /// Invalid drop function in vtable. |
210 | InvalidDropFn(FnSig<'tcx>), | |
ba9703b0 XL |
211 | /// Reading a C string that does not end within its allocation. |
212 | UnterminatedCString(Pointer), | |
213 | /// Dereferencing a dangling pointer after it got freed. | |
214 | PointerUseAfterFree(AllocId), | |
215 | /// Used a pointer outside the bounds it is valid for. | |
216 | PointerOutOfBounds { | |
217 | ptr: Pointer, | |
218 | msg: CheckInAllocMsg, | |
219 | allocation_size: Size, | |
220 | }, | |
f9f354fc XL |
221 | /// Using an integer as a pointer in the wrong way. |
222 | DanglingIntPointer(u64, CheckInAllocMsg), | |
ba9703b0 XL |
223 | /// Used a pointer with bad alignment. |
224 | AlignmentCheckFailed { | |
225 | required: Align, | |
226 | has: Align, | |
227 | }, | |
ba9703b0 XL |
228 | /// Writing to read-only memory. |
229 | WriteToReadOnly(AllocId), | |
ba9703b0 XL |
230 | // Trying to access the data behind a function pointer. |
231 | DerefFunctionPointer(AllocId), | |
232 | /// The value validity check found a problem. | |
233 | /// Should only be thrown by `validity.rs` and always point out which part of the value | |
234 | /// is the problem. | |
235 | ValidationFailure(String), | |
236 | /// Using a non-boolean `u8` as bool. | |
237 | InvalidBool(u8), | |
238 | /// Using a non-character `u32` as character. | |
239 | InvalidChar(u32), | |
f035d41b XL |
240 | /// The tag of an enum does not encode an actual discriminant. |
241 | InvalidTag(Scalar), | |
f9f354fc XL |
242 | /// Using a pointer-not-to-a-function as function pointer. |
243 | InvalidFunctionPointer(Pointer), | |
244 | /// Using a string that is not valid UTF-8, | |
245 | InvalidStr(std::str::Utf8Error), | |
ba9703b0 | 246 | /// Using uninitialized data where it is not allowed. |
f9f354fc | 247 | InvalidUninitBytes(Option<Box<UninitBytesAccess>>), |
ba9703b0 XL |
248 | /// Working with a local that is not currently live. |
249 | DeadLocal, | |
f9f354fc XL |
250 | /// Data size is not equal to target size. |
251 | ScalarSizeMismatch { | |
252 | target_size: u64, | |
253 | data_size: u64, | |
254 | }, | |
416331ca | 255 | } |
48663c56 | 256 | |
f9f354fc | 257 | impl fmt::Display for UndefinedBehaviorInfo<'_> { |
416331ca XL |
258 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
259 | use UndefinedBehaviorInfo::*; | |
260 | match self { | |
ba9703b0 | 261 | Ub(msg) => write!(f, "{}", msg), |
dfeec247 | 262 | Unreachable => write!(f, "entering unreachable code"), |
f9f354fc XL |
263 | BoundsCheckFailed { ref len, ref index } => { |
264 | write!(f, "indexing out of bounds: the len is {} but the index is {}", len, index) | |
265 | } | |
dfeec247 XL |
266 | DivisionByZero => write!(f, "dividing by zero"), |
267 | RemainderByZero => write!(f, "calculating the remainder with a divisor of zero"), | |
268 | PointerArithOverflow => write!(f, "overflowing in-bounds pointer arithmetic"), | |
74b04a01 | 269 | InvalidMeta(msg) => write!(f, "invalid metadata in wide pointer: {}", msg), |
f9f354fc XL |
270 | InvalidDropFn(sig) => write!( |
271 | f, | |
272 | "invalid drop function signature: got {}, expected exactly one argument which must be a pointer type", | |
273 | sig | |
274 | ), | |
ba9703b0 XL |
275 | UnterminatedCString(p) => write!( |
276 | f, | |
f9f354fc | 277 | "reading a null-terminated string starting at {} with no null found before end of allocation", |
ba9703b0 XL |
278 | p, |
279 | ), | |
280 | PointerUseAfterFree(a) => { | |
f9f354fc | 281 | write!(f, "pointer to {} was dereferenced after this allocation got freed", a) |
ba9703b0 XL |
282 | } |
283 | PointerOutOfBounds { ptr, msg, allocation_size } => write!( | |
284 | f, | |
285 | "{} failed: pointer must be in-bounds at offset {}, \ | |
286 | but is outside bounds of {} which has size {}", | |
287 | msg, | |
288 | ptr.offset.bytes(), | |
289 | ptr.alloc_id, | |
290 | allocation_size.bytes() | |
291 | ), | |
f9f354fc XL |
292 | DanglingIntPointer(_, CheckInAllocMsg::NullPointerTest) => { |
293 | write!(f, "NULL pointer is not allowed for this operation") | |
294 | } | |
295 | DanglingIntPointer(i, msg) => { | |
296 | write!(f, "{} failed: 0x{:x} is not a valid pointer", msg, i) | |
297 | } | |
ba9703b0 XL |
298 | AlignmentCheckFailed { required, has } => write!( |
299 | f, | |
300 | "accessing memory with alignment {}, but alignment {} is required", | |
301 | has.bytes(), | |
302 | required.bytes() | |
303 | ), | |
f9f354fc XL |
304 | WriteToReadOnly(a) => write!(f, "writing to {} which is read-only", a), |
305 | DerefFunctionPointer(a) => write!(f, "accessing {} which contains a function", a), | |
306 | ValidationFailure(ref err) => write!(f, "type validation failed: {}", err), | |
307 | InvalidBool(b) => { | |
308 | write!(f, "interpreting an invalid 8-bit value as a bool: 0x{:02x}", b) | |
309 | } | |
310 | InvalidChar(c) => { | |
311 | write!(f, "interpreting an invalid 32-bit value as a char: 0x{:08x}", c) | |
312 | } | |
f035d41b | 313 | InvalidTag(val) => write!(f, "enum value has invalid tag: {}", val), |
ba9703b0 | 314 | InvalidFunctionPointer(p) => { |
f9f354fc | 315 | write!(f, "using {} as function pointer but it does not point to a function", p) |
ba9703b0 | 316 | } |
f9f354fc XL |
317 | InvalidStr(err) => write!(f, "this string is not valid UTF-8: {}", err), |
318 | InvalidUninitBytes(Some(access)) => write!( | |
ba9703b0 | 319 | f, |
f9f354fc XL |
320 | "reading {} byte{} of memory starting at {}, \ |
321 | but {} byte{} {} uninitialized starting at {}, \ | |
322 | and this operation requires initialized memory", | |
323 | access.access_size.bytes(), | |
324 | pluralize!(access.access_size.bytes()), | |
325 | access.access_ptr, | |
326 | access.uninit_size.bytes(), | |
327 | pluralize!(access.uninit_size.bytes()), | |
328 | if access.uninit_size.bytes() != 1 { "are" } else { "is" }, | |
329 | access.uninit_ptr, | |
ba9703b0 | 330 | ), |
f9f354fc | 331 | InvalidUninitBytes(None) => write!( |
ba9703b0 XL |
332 | f, |
333 | "using uninitialized data, but this operation requires initialized memory" | |
334 | ), | |
335 | DeadLocal => write!(f, "accessing a dead local variable"), | |
f9f354fc XL |
336 | ScalarSizeMismatch { target_size, data_size } => write!( |
337 | f, | |
338 | "scalar size mismatch: expected {} bytes but got {} bytes instead", | |
339 | target_size, data_size | |
340 | ), | |
416331ca XL |
341 | } |
342 | } | |
343 | } | |
344 | ||
e1599b0c XL |
345 | /// Error information for when the program did something that might (or might not) be correct |
346 | /// to do according to the Rust spec, but due to limitations in the interpreter, the | |
347 | /// operation could not be carried out. These limitations can differ between CTFE and the | |
f9f354fc | 348 | /// Miri engine, e.g., CTFE does not support dereferencing pointers at integral addresses. |
ba9703b0 | 349 | pub enum UnsupportedOpInfo { |
416331ca XL |
350 | /// Free-form case. Only for errors that are never caught! |
351 | Unsupported(String), | |
ba9703b0 XL |
352 | /// Could not find MIR for a function. |
353 | NoMirFor(DefId), | |
354 | /// Encountered a pointer where we needed raw bytes. | |
ea8adc8c | 355 | ReadPointerAsBytes, |
f9f354fc XL |
356 | // |
357 | // The variants below are only reachable from CTFE/const prop, miri will never emit them. | |
358 | // | |
ba9703b0 | 359 | /// Encountered raw bytes where we needed a pointer. |
ea8adc8c | 360 | ReadBytesAsPointer, |
f9f354fc XL |
361 | /// Accessing thread local statics |
362 | ThreadLocalStatic(DefId), | |
3dfed10e XL |
363 | /// Accessing an unsupported extern static. |
364 | ReadExternStatic(DefId), | |
ea8adc8c XL |
365 | } |
366 | ||
f9f354fc | 367 | impl fmt::Display for UnsupportedOpInfo { |
a1dfa0c6 | 368 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
416331ca XL |
369 | use UnsupportedOpInfo::*; |
370 | match self { | |
dfeec247 | 371 | Unsupported(ref msg) => write!(f, "{}", msg), |
3dfed10e | 372 | ReadExternStatic(did) => write!(f, "cannot read from extern static ({:?})", did), |
ba9703b0 XL |
373 | NoMirFor(did) => write!(f, "no MIR body is available for {:?}", did), |
374 | ReadPointerAsBytes => write!(f, "unable to turn pointer into raw bytes",), | |
375 | ReadBytesAsPointer => write!(f, "unable to turn bytes into a pointer"), | |
f9f354fc | 376 | ThreadLocalStatic(did) => write!(f, "cannot access thread local static ({:?})", did), |
416331ca XL |
377 | } |
378 | } | |
379 | } | |
380 | ||
e1599b0c XL |
381 | /// Error information for when the program exhausted the resources granted to it |
382 | /// by the interpreter. | |
416331ca XL |
383 | pub enum ResourceExhaustionInfo { |
384 | /// The stack grew too big. | |
385 | StackFrameLimitReached, | |
ba9703b0 XL |
386 | /// The program ran for too long. |
387 | /// | |
388 | /// The exact limit is set by the `const_eval_limit` attribute. | |
389 | StepLimitReached, | |
416331ca XL |
390 | } |
391 | ||
f9f354fc | 392 | impl fmt::Display for ResourceExhaustionInfo { |
416331ca XL |
393 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
394 | use ResourceExhaustionInfo::*; | |
395 | match self { | |
dfeec247 XL |
396 | StackFrameLimitReached => { |
397 | write!(f, "reached the configured maximum number of stack frames") | |
398 | } | |
ba9703b0 XL |
399 | StepLimitReached => { |
400 | write!(f, "exceeded interpreter step limit (see `#[const_eval_limit]`)") | |
401 | } | |
416331ca XL |
402 | } |
403 | } | |
404 | } | |
405 | ||
ba9703b0 XL |
406 | /// A trait to work around not having trait object upcasting. |
407 | pub trait AsAny: Any { | |
408 | fn as_any(&self) -> &dyn Any; | |
409 | } | |
ba9703b0 XL |
410 | impl<T: Any> AsAny for T { |
411 | #[inline(always)] | |
412 | fn as_any(&self) -> &dyn Any { | |
413 | self | |
414 | } | |
415 | } | |
416 | ||
417 | /// A trait for machine-specific errors (or other "machine stop" conditions). | |
f9f354fc | 418 | pub trait MachineStopType: AsAny + fmt::Display + Send {} |
ba9703b0 XL |
419 | impl MachineStopType for String {} |
420 | ||
421 | impl dyn MachineStopType { | |
422 | #[inline(always)] | |
423 | pub fn downcast_ref<T: Any>(&self) -> Option<&T> { | |
424 | self.as_any().downcast_ref() | |
425 | } | |
426 | } | |
427 | ||
f9f354fc XL |
428 | #[cfg(target_arch = "x86_64")] |
429 | static_assert_size!(InterpError<'_>, 40); | |
430 | ||
416331ca | 431 | pub enum InterpError<'tcx> { |
416331ca | 432 | /// The program caused undefined behavior. |
f9f354fc | 433 | UndefinedBehavior(UndefinedBehaviorInfo<'tcx>), |
416331ca XL |
434 | /// The program did something the interpreter does not support (some of these *might* be UB |
435 | /// but the interpreter is not sure). | |
ba9703b0 | 436 | Unsupported(UnsupportedOpInfo), |
60c5eb7d | 437 | /// The program was invalid (ill-typed, bad MIR, not sufficiently monomorphized, ...). |
416331ca XL |
438 | InvalidProgram(InvalidProgramInfo<'tcx>), |
439 | /// The program exhausted the interpreter's resources (stack/heap too big, | |
60c5eb7d | 440 | /// execution takes too long, ...). |
416331ca | 441 | ResourceExhaustion(ResourceExhaustionInfo), |
60c5eb7d XL |
442 | /// Stop execution for a machine-controlled reason. This is never raised by |
443 | /// the core engine itself. | |
ba9703b0 | 444 | MachineStop(Box<dyn MachineStopType>), |
416331ca XL |
445 | } |
446 | ||
447 | pub type InterpResult<'tcx, T = ()> = Result<T, InterpErrorInfo<'tcx>>; | |
448 | ||
449 | impl fmt::Display for InterpError<'_> { | |
450 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { | |
f9f354fc XL |
451 | use InterpError::*; |
452 | match *self { | |
453 | Unsupported(ref msg) => write!(f, "{}", msg), | |
454 | InvalidProgram(ref msg) => write!(f, "{}", msg), | |
455 | UndefinedBehavior(ref msg) => write!(f, "{}", msg), | |
456 | ResourceExhaustion(ref msg) => write!(f, "{}", msg), | |
457 | MachineStop(ref msg) => write!(f, "{}", msg), | |
458 | } | |
416331ca XL |
459 | } |
460 | } | |
461 | ||
f9f354fc | 462 | // Forward `Debug` to `Display`, so it does not look awful. |
416331ca XL |
463 | impl fmt::Debug for InterpError<'_> { |
464 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { | |
f9f354fc | 465 | fmt::Display::fmt(self, f) |
74b04a01 XL |
466 | } |
467 | } | |
468 | ||
469 | impl InterpError<'_> { | |
470 | /// Some errors allocate to be created as they contain free-form strings. | |
471 | /// And sometimes we want to be sure that did not happen as it is a | |
472 | /// waste of resources. | |
473 | pub fn allocates(&self) -> bool { | |
474 | match self { | |
ba9703b0 XL |
475 | // Zero-sized boxes do not allocate. |
476 | InterpError::MachineStop(b) => mem::size_of_val::<dyn MachineStopType>(&**b) > 0, | |
477 | InterpError::Unsupported(UnsupportedOpInfo::Unsupported(_)) | |
478 | | InterpError::UndefinedBehavior(UndefinedBehaviorInfo::ValidationFailure(_)) | |
f9f354fc XL |
479 | | InterpError::UndefinedBehavior(UndefinedBehaviorInfo::Ub(_)) |
480 | | InterpError::UndefinedBehavior(UndefinedBehaviorInfo::InvalidUninitBytes(Some(_))) => { | |
481 | true | |
482 | } | |
74b04a01 | 483 | _ => false, |
ea8adc8c XL |
484 | } |
485 | } | |
486 | } |