1 //! Type-checking for the rust-intrinsic and platform-intrinsic
2 //! intrinsics that the compiler exposes.
5 UnrecognizedAtomicOperation, UnrecognizedIntrinsicFunction,
6 WrongNumberOfGenericArgumentsToIntrinsic,
8 use crate::require_same_types;
10 use hir::def_id::DefId;
11 use rustc_errors::{struct_span_err, DiagnosticMessage};
13 use rustc_middle::traits::{ObligationCause, ObligationCauseCode};
14 use rustc_middle::ty::{self, TyCtxt};
15 use rustc_span::symbol::{kw, sym, Symbol};
16 use rustc_target::spec::abi::Abi;
20 fn equate_intrinsic_type<'tcx>(
22 it: &hir::ForeignItem<'_>,
25 sig: ty::PolyFnSig<'tcx>,
27 let (own_counts, span) = match &it.kind {
28 hir::ForeignItemKind::Fn(.., generics) => {
29 let own_counts = tcx.generics_of(it.owner_id.to_def_id()).own_counts();
30 (own_counts, generics.span)
33 struct_span_err!(tcx.sess, it.span, E0622, "intrinsic must be a function")
34 .span_label(it.span, "expected a function")
40 let gen_count_ok = |found: usize, expected: usize, descr: &str| -> bool {
41 if found != expected {
42 tcx.sess.emit_err(WrongNumberOfGenericArgumentsToIntrinsic {
54 if gen_count_ok(own_counts.lifetimes, n_lts, "lifetime")
55 && gen_count_ok(own_counts.types, n_tps, "type")
56 && gen_count_ok(own_counts.consts, 0, "const")
58 let fty = tcx.mk_fn_ptr(sig);
59 let it_def_id = it.owner_id.def_id;
60 let cause = ObligationCause::new(it.span, it_def_id, ObligationCauseCode::IntrinsicType);
64 tcx.mk_fn_ptr(tcx.fn_sig(it.owner_id).subst_identity()),
70 /// Returns the unsafety of the given intrinsic.
71 pub fn intrinsic_operation_unsafety(tcx: TyCtxt<'_>, intrinsic_id: DefId) -> hir::Unsafety {
72 let has_safe_attr = match tcx.has_attr(intrinsic_id, sym::rustc_safe_intrinsic) {
73 true => hir::Unsafety::Normal,
74 false => hir::Unsafety::Unsafe,
76 let is_in_list = match tcx.item_name(intrinsic_id) {
77 // When adding a new intrinsic to this list,
78 // it's usually worth updating that intrinsic's documentation
79 // to note that it's safe to call, since
80 // safe extern fns are otherwise unprecedented.
82 | sym::assert_inhabited
83 | sym::assert_zero_valid
84 | sym::assert_mem_uninitialized_valid
88 | sym::caller_location
89 | sym::add_with_overflow
90 | sym::sub_with_overflow
91 | sym::mul_with_overflow
104 | sym::discriminant_value
108 | sym::ptr_guaranteed_cmp
118 | sym::ptr_mask => hir::Unsafety::Normal,
119 _ => hir::Unsafety::Unsafe,
122 if has_safe_attr != is_in_list {
123 tcx.sess.struct_span_err(
124 tcx.def_span(intrinsic_id),
125 DiagnosticMessage::Str(format!(
126 "intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `{}`",
127 tcx.item_name(intrinsic_id)
134 /// Remember to add all intrinsics here, in `compiler/rustc_codegen_llvm/src/intrinsic.rs`,
135 /// and in `library/core/src/intrinsics.rs`.
136 pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
137 let param = |n| tcx.mk_ty_param(n, Symbol::intern(&format!("P{}", n)));
138 let intrinsic_id = it.owner_id.to_def_id();
139 let intrinsic_name = tcx.item_name(intrinsic_id);
140 let name_str = intrinsic_name.as_str();
142 let bound_vars = tcx.mk_bound_variable_kinds(
144 ty::BoundVariableKind::Region(ty::BrAnon(0, None)),
145 ty::BoundVariableKind::Region(ty::BrEnv),
150 let mk_va_list_ty = |mutbl| {
151 tcx.lang_items().va_list().map(|did| {
152 let region = tcx.mk_region(ty::ReLateBound(
154 ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0, None) },
156 let env_region = tcx.mk_region(ty::ReLateBound(
158 ty::BoundRegion { var: ty::BoundVar::from_u32(1), kind: ty::BrEnv },
160 let va_list_ty = tcx.bound_type_of(did).subst(tcx, &[region.into()]);
161 (tcx.mk_ref(env_region, ty::TypeAndMut { ty: va_list_ty, mutbl }), va_list_ty)
165 let (n_tps, n_lts, inputs, output, unsafety) = if name_str.starts_with("atomic_") {
166 let split: Vec<&str> = name_str.split('_').collect();
167 assert!(split.len() >= 2, "Atomic intrinsic in an incorrect format");
169 //We only care about the operation here
170 let (n_tps, inputs, output) = match split[1] {
171 "cxchg" | "cxchgweak" => (
173 vec![tcx.mk_mut_ptr(param(0)), param(0), param(0)],
174 tcx.intern_tup(&[param(0), tcx.types.bool]),
176 "load" => (1, vec![tcx.mk_imm_ptr(param(0))], param(0)),
177 "store" => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
179 "xchg" | "xadd" | "xsub" | "and" | "nand" | "or" | "xor" | "max" | "min" | "umax"
180 | "umin" => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], param(0)),
181 "fence" | "singlethreadfence" => (0, Vec::new(), tcx.mk_unit()),
183 tcx.sess.emit_err(UnrecognizedAtomicOperation { span: it.span, op });
187 (n_tps, 0, inputs, output, hir::Unsafety::Unsafe)
189 let unsafety = intrinsic_operation_unsafety(tcx, intrinsic_id);
190 let (n_tps, inputs, output) = match intrinsic_name {
191 sym::abort => (0, Vec::new(), tcx.types.never),
192 sym::unreachable => (0, Vec::new(), tcx.types.never),
193 sym::breakpoint => (0, Vec::new(), tcx.mk_unit()),
194 sym::size_of | sym::pref_align_of | sym::min_align_of | sym::variant_count => {
195 (1, Vec::new(), tcx.types.usize)
197 sym::size_of_val | sym::min_align_of_val => {
198 (1, vec![tcx.mk_imm_ptr(param(0))], tcx.types.usize)
200 sym::rustc_peek => (1, vec![param(0)], param(0)),
201 sym::caller_location => (0, vec![], tcx.caller_location_ty()),
202 sym::assert_inhabited
203 | sym::assert_zero_valid
204 | sym::assert_mem_uninitialized_valid => (1, Vec::new(), tcx.mk_unit()),
205 sym::forget => (1, vec![param(0)], tcx.mk_unit()),
206 sym::transmute => (2, vec![param(0)], param(1)),
207 sym::prefetch_read_data
208 | sym::prefetch_write_data
209 | sym::prefetch_read_instruction
210 | sym::prefetch_write_instruction => (
213 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
218 sym::drop_in_place => (1, vec![tcx.mk_mut_ptr(param(0))], tcx.mk_unit()),
219 sym::needs_drop => (1, Vec::new(), tcx.types.bool),
221 sym::type_name => (1, Vec::new(), tcx.mk_static_str()),
222 sym::type_id => (1, Vec::new(), tcx.types.u64),
223 sym::offset | sym::arith_offset => (
226 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
229 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
234 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
237 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
240 sym::copy | sym::copy_nonoverlapping => (
243 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
244 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
249 sym::volatile_copy_memory | sym::volatile_copy_nonoverlapping_memory => (
252 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
253 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
258 sym::write_bytes | sym::volatile_set_memory => (
261 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
267 sym::sqrtf32 => (0, vec![tcx.types.f32], tcx.types.f32),
268 sym::sqrtf64 => (0, vec![tcx.types.f64], tcx.types.f64),
269 sym::powif32 => (0, vec![tcx.types.f32, tcx.types.i32], tcx.types.f32),
270 sym::powif64 => (0, vec![tcx.types.f64, tcx.types.i32], tcx.types.f64),
271 sym::sinf32 => (0, vec![tcx.types.f32], tcx.types.f32),
272 sym::sinf64 => (0, vec![tcx.types.f64], tcx.types.f64),
273 sym::cosf32 => (0, vec![tcx.types.f32], tcx.types.f32),
274 sym::cosf64 => (0, vec![tcx.types.f64], tcx.types.f64),
275 sym::powf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
276 sym::powf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
277 sym::expf32 => (0, vec![tcx.types.f32], tcx.types.f32),
278 sym::expf64 => (0, vec![tcx.types.f64], tcx.types.f64),
279 sym::exp2f32 => (0, vec![tcx.types.f32], tcx.types.f32),
280 sym::exp2f64 => (0, vec![tcx.types.f64], tcx.types.f64),
281 sym::logf32 => (0, vec![tcx.types.f32], tcx.types.f32),
282 sym::logf64 => (0, vec![tcx.types.f64], tcx.types.f64),
283 sym::log10f32 => (0, vec![tcx.types.f32], tcx.types.f32),
284 sym::log10f64 => (0, vec![tcx.types.f64], tcx.types.f64),
285 sym::log2f32 => (0, vec![tcx.types.f32], tcx.types.f32),
286 sym::log2f64 => (0, vec![tcx.types.f64], tcx.types.f64),
287 sym::fmaf32 => (0, vec![tcx.types.f32, tcx.types.f32, tcx.types.f32], tcx.types.f32),
288 sym::fmaf64 => (0, vec![tcx.types.f64, tcx.types.f64, tcx.types.f64], tcx.types.f64),
289 sym::fabsf32 => (0, vec![tcx.types.f32], tcx.types.f32),
290 sym::fabsf64 => (0, vec![tcx.types.f64], tcx.types.f64),
291 sym::minnumf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
292 sym::minnumf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
293 sym::maxnumf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
294 sym::maxnumf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
295 sym::copysignf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
296 sym::copysignf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
297 sym::floorf32 => (0, vec![tcx.types.f32], tcx.types.f32),
298 sym::floorf64 => (0, vec![tcx.types.f64], tcx.types.f64),
299 sym::ceilf32 => (0, vec![tcx.types.f32], tcx.types.f32),
300 sym::ceilf64 => (0, vec![tcx.types.f64], tcx.types.f64),
301 sym::truncf32 => (0, vec![tcx.types.f32], tcx.types.f32),
302 sym::truncf64 => (0, vec![tcx.types.f64], tcx.types.f64),
303 sym::rintf32 => (0, vec![tcx.types.f32], tcx.types.f32),
304 sym::rintf64 => (0, vec![tcx.types.f64], tcx.types.f64),
305 sym::nearbyintf32 => (0, vec![tcx.types.f32], tcx.types.f32),
306 sym::nearbyintf64 => (0, vec![tcx.types.f64], tcx.types.f64),
307 sym::roundf32 => (0, vec![tcx.types.f32], tcx.types.f32),
308 sym::roundf64 => (0, vec![tcx.types.f64], tcx.types.f64),
310 sym::volatile_load | sym::unaligned_volatile_load => {
311 (1, vec![tcx.mk_imm_ptr(param(0))], param(0))
313 sym::volatile_store | sym::unaligned_volatile_store => {
314 (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit())
323 | sym::bitreverse => (1, vec![param(0)], param(0)),
325 sym::add_with_overflow | sym::sub_with_overflow | sym::mul_with_overflow => {
326 (1, vec![param(0), param(0)], tcx.intern_tup(&[param(0), tcx.types.bool]))
329 sym::ptr_guaranteed_cmp => {
330 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.u8)
333 sym::const_allocate => {
334 (0, vec![tcx.types.usize, tcx.types.usize], tcx.mk_mut_ptr(tcx.types.u8))
336 sym::const_deallocate => (
338 vec![tcx.mk_mut_ptr(tcx.types.u8), tcx.types.usize, tcx.types.usize],
342 sym::ptr_offset_from => {
343 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.isize)
345 sym::ptr_offset_from_unsigned => {
346 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.usize)
348 sym::unchecked_div | sym::unchecked_rem | sym::exact_div => {
349 (1, vec![param(0), param(0)], param(0))
351 sym::unchecked_shl | sym::unchecked_shr | sym::rotate_left | sym::rotate_right => {
352 (1, vec![param(0), param(0)], param(0))
354 sym::unchecked_add | sym::unchecked_sub | sym::unchecked_mul => {
355 (1, vec![param(0), param(0)], param(0))
357 sym::wrapping_add | sym::wrapping_sub | sym::wrapping_mul => {
358 (1, vec![param(0), param(0)], param(0))
360 sym::saturating_add | sym::saturating_sub => (1, vec![param(0), param(0)], param(0)),
361 sym::fadd_fast | sym::fsub_fast | sym::fmul_fast | sym::fdiv_fast | sym::frem_fast => {
362 (1, vec![param(0), param(0)], param(0))
364 sym::float_to_int_unchecked => (2, vec![param(0)], param(1)),
366 sym::assume => (0, vec![tcx.types.bool], tcx.mk_unit()),
367 sym::likely => (0, vec![tcx.types.bool], tcx.types.bool),
368 sym::unlikely => (0, vec![tcx.types.bool], tcx.types.bool),
370 sym::discriminant_value => {
371 let assoc_items = tcx.associated_item_def_ids(
372 tcx.require_lang_item(hir::LangItem::DiscriminantKind, None),
374 let discriminant_def_id = assoc_items[0];
377 ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0, None) };
381 tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0)),
383 tcx.mk_projection(discriminant_def_id, tcx.mk_substs([param(0).into()].iter())),
388 let mut_u8 = tcx.mk_mut_ptr(tcx.types.u8);
389 let try_fn_ty = ty::Binder::dummy(tcx.mk_fn_sig(
393 hir::Unsafety::Normal,
396 let catch_fn_ty = ty::Binder::dummy(tcx.mk_fn_sig(
397 [mut_u8, mut_u8].iter().cloned(),
400 hir::Unsafety::Normal,
405 vec![tcx.mk_fn_ptr(try_fn_ty), mut_u8, tcx.mk_fn_ptr(catch_fn_ty)],
410 sym::va_start | sym::va_end => match mk_va_list_ty(hir::Mutability::Mut) {
411 Some((va_list_ref_ty, _)) => (0, vec![va_list_ref_ty], tcx.mk_unit()),
412 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
415 sym::va_copy => match mk_va_list_ty(hir::Mutability::Not) {
416 Some((va_list_ref_ty, va_list_ty)) => {
417 let va_list_ptr_ty = tcx.mk_mut_ptr(va_list_ty);
418 (0, vec![va_list_ptr_ty, va_list_ref_ty], tcx.mk_unit())
420 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
423 sym::va_arg => match mk_va_list_ty(hir::Mutability::Mut) {
424 Some((va_list_ref_ty, _)) => (1, vec![va_list_ref_ty], param(0)),
425 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
428 sym::nontemporal_store => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
432 ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0, None) };
434 tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0));
435 (1, vec![param_ty; 2], tcx.types.bool)
438 sym::black_box => (1, vec![param(0)], param(0)),
440 sym::const_eval_select => (4, vec![param(0), param(1), param(2)], param(3)),
442 sym::vtable_size | sym::vtable_align => {
443 (0, vec![tcx.mk_imm_ptr(tcx.mk_unit())], tcx.types.usize)
447 tcx.sess.emit_err(UnrecognizedIntrinsicFunction { span: it.span, name: other });
451 (n_tps, 0, inputs, output, unsafety)
453 let sig = tcx.mk_fn_sig(inputs.into_iter(), output, false, unsafety, Abi::RustIntrinsic);
454 let sig = ty::Binder::bind_with_vars(sig, bound_vars);
455 equate_intrinsic_type(tcx, it, n_tps, n_lts, sig)
458 /// Type-check `extern "platform-intrinsic" { ... }` functions.
459 pub fn check_platform_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
461 let name = Symbol::intern(&format!("P{}", n));
462 tcx.mk_ty_param(n, name)
465 let name = it.ident.name;
467 let (n_tps, inputs, output) = match name {
468 sym::simd_eq | sym::simd_ne | sym::simd_lt | sym::simd_le | sym::simd_gt | sym::simd_ge => {
469 (2, vec![param(0), param(0)], param(1))
484 | sym::simd_saturating_add
485 | sym::simd_saturating_sub => (1, vec![param(0), param(0)], param(0)),
486 sym::simd_arith_offset => (2, vec![param(0), param(1)], param(0)),
500 | sym::simd_trunc => (1, vec![param(0)], param(0)),
501 sym::simd_fpowi => (1, vec![param(0), tcx.types.i32], param(0)),
502 sym::simd_fma => (1, vec![param(0), param(0), param(0)], param(0)),
503 sym::simd_gather => (3, vec![param(0), param(1), param(2)], param(0)),
504 sym::simd_scatter => (3, vec![param(0), param(1), param(2)], tcx.mk_unit()),
505 sym::simd_insert => (2, vec![param(0), tcx.types.u32, param(1)], param(0)),
506 sym::simd_extract => (2, vec![param(0), tcx.types.u32], param(1)),
510 | sym::simd_expose_addr
511 | sym::simd_from_exposed_addr => (2, vec![param(0)], param(1)),
512 sym::simd_bitmask => (2, vec![param(0)], param(1)),
513 sym::simd_select | sym::simd_select_bitmask => {
514 (2, vec![param(0), param(1), param(1)], param(1))
516 sym::simd_reduce_all | sym::simd_reduce_any => (1, vec![param(0)], tcx.types.bool),
517 sym::simd_reduce_add_ordered | sym::simd_reduce_mul_ordered => {
518 (2, vec![param(0), param(1)], param(1))
520 sym::simd_reduce_add_unordered
521 | sym::simd_reduce_mul_unordered
522 | sym::simd_reduce_and
523 | sym::simd_reduce_or
524 | sym::simd_reduce_xor
525 | sym::simd_reduce_min
526 | sym::simd_reduce_max
527 | sym::simd_reduce_min_nanless
528 | sym::simd_reduce_max_nanless => (2, vec![param(0)], param(1)),
529 sym::simd_shuffle => (3, vec![param(0), param(0), param(1)], param(2)),
530 name if name.as_str().starts_with("simd_shuffle") => {
531 match name.as_str()["simd_shuffle".len()..].parse() {
533 let params = vec![param(0), param(0), tcx.mk_array(tcx.types.u32, n)];
534 (2, params, param(1))
538 format!("unrecognized platform-specific intrinsic function: `{name}`");
539 tcx.sess.struct_span_err(it.span, &msg).emit();
545 let msg = format!("unrecognized platform-specific intrinsic function: `{name}`");
546 tcx.sess.struct_span_err(it.span, &msg).emit();
551 let sig = tcx.mk_fn_sig(
555 hir::Unsafety::Unsafe,
556 Abi::PlatformIntrinsic,
558 let sig = ty::Binder::dummy(sig);
559 equate_intrinsic_type(tcx, it, n_tps, 0, sig)