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.def_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 cause = ObligationCause::new(it.span, it.hir_id(), ObligationCauseCode::IntrinsicType);
60 require_same_types(tcx, &cause, tcx.mk_fn_ptr(tcx.fn_sig(it.def_id)), fty);
64 /// Returns the unsafety of the given intrinsic.
65 pub fn intrinsic_operation_unsafety(tcx: TyCtxt<'_>, intrinsic_id: DefId) -> hir::Unsafety {
66 let has_safe_attr = match tcx.has_attr(intrinsic_id, sym::rustc_safe_intrinsic) {
67 true => hir::Unsafety::Normal,
68 false => hir::Unsafety::Unsafe,
70 let is_in_list = match tcx.item_name(intrinsic_id) {
71 // When adding a new intrinsic to this list,
72 // it's usually worth updating that intrinsic's documentation
73 // to note that it's safe to call, since
74 // safe extern fns are otherwise unprecedented.
76 | sym::assert_inhabited
77 | sym::assert_zero_valid
78 | sym::assert_uninit_valid
82 | sym::caller_location
83 | sym::add_with_overflow
84 | sym::sub_with_overflow
85 | sym::mul_with_overflow
98 | sym::discriminant_value
102 | sym::ptr_guaranteed_cmp
112 | sym::ptr_mask => hir::Unsafety::Normal,
113 _ => hir::Unsafety::Unsafe,
116 if has_safe_attr != is_in_list {
117 tcx.sess.struct_span_err(
118 tcx.def_span(intrinsic_id),
119 DiagnosticMessage::Str(format!(
120 "intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `{}`",
121 tcx.item_name(intrinsic_id)
128 /// Remember to add all intrinsics here, in `compiler/rustc_codegen_llvm/src/intrinsic.rs`,
129 /// and in `library/core/src/intrinsics.rs`.
130 pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
131 let param = |n| tcx.mk_ty_param(n, Symbol::intern(&format!("P{}", n)));
132 let intrinsic_id = it.def_id.to_def_id();
133 let intrinsic_name = tcx.item_name(intrinsic_id);
134 let name_str = intrinsic_name.as_str();
136 let bound_vars = tcx.mk_bound_variable_kinds(
137 [ty::BoundVariableKind::Region(ty::BrAnon(0)), ty::BoundVariableKind::Region(ty::BrEnv)]
141 let mk_va_list_ty = |mutbl| {
142 tcx.lang_items().va_list().map(|did| {
143 let region = tcx.mk_region(ty::ReLateBound(
145 ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) },
147 let env_region = tcx.mk_region(ty::ReLateBound(
149 ty::BoundRegion { var: ty::BoundVar::from_u32(1), kind: ty::BrEnv },
151 let va_list_ty = tcx.bound_type_of(did).subst(tcx, &[region.into()]);
152 (tcx.mk_ref(env_region, ty::TypeAndMut { ty: va_list_ty, mutbl }), va_list_ty)
156 let (n_tps, n_lts, inputs, output, unsafety) = if name_str.starts_with("atomic_") {
157 let split: Vec<&str> = name_str.split('_').collect();
158 assert!(split.len() >= 2, "Atomic intrinsic in an incorrect format");
160 //We only care about the operation here
161 let (n_tps, inputs, output) = match split[1] {
162 "cxchg" | "cxchgweak" => (
164 vec![tcx.mk_mut_ptr(param(0)), param(0), param(0)],
165 tcx.intern_tup(&[param(0), tcx.types.bool]),
167 "load" => (1, vec![tcx.mk_imm_ptr(param(0))], param(0)),
168 "store" => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
170 "xchg" | "xadd" | "xsub" | "and" | "nand" | "or" | "xor" | "max" | "min" | "umax"
171 | "umin" => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], param(0)),
172 "fence" | "singlethreadfence" => (0, Vec::new(), tcx.mk_unit()),
174 tcx.sess.emit_err(UnrecognizedAtomicOperation { span: it.span, op });
178 (n_tps, 0, inputs, output, hir::Unsafety::Unsafe)
180 let unsafety = intrinsic_operation_unsafety(tcx, intrinsic_id);
181 let (n_tps, inputs, output) = match intrinsic_name {
182 sym::abort => (0, Vec::new(), tcx.types.never),
183 sym::unreachable => (0, Vec::new(), tcx.types.never),
184 sym::breakpoint => (0, Vec::new(), tcx.mk_unit()),
185 sym::size_of | sym::pref_align_of | sym::min_align_of | sym::variant_count => {
186 (1, Vec::new(), tcx.types.usize)
188 sym::size_of_val | sym::min_align_of_val => {
189 (1, vec![tcx.mk_imm_ptr(param(0))], tcx.types.usize)
191 sym::rustc_peek => (1, vec![param(0)], param(0)),
192 sym::caller_location => (0, vec![], tcx.caller_location_ty()),
193 sym::assert_inhabited | sym::assert_zero_valid | sym::assert_uninit_valid => {
194 (1, Vec::new(), tcx.mk_unit())
196 sym::forget => (1, vec![param(0)], tcx.mk_unit()),
197 sym::transmute => (2, vec![param(0)], param(1)),
198 sym::prefetch_read_data
199 | sym::prefetch_write_data
200 | sym::prefetch_read_instruction
201 | sym::prefetch_write_instruction => (
204 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
209 sym::drop_in_place => (1, vec![tcx.mk_mut_ptr(param(0))], tcx.mk_unit()),
210 sym::needs_drop => (1, Vec::new(), tcx.types.bool),
212 sym::type_name => (1, Vec::new(), tcx.mk_static_str()),
213 sym::type_id => (1, Vec::new(), tcx.types.u64),
214 sym::offset | sym::arith_offset => (
217 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
220 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
225 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
228 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
231 sym::copy | sym::copy_nonoverlapping => (
234 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
235 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
240 sym::volatile_copy_memory | sym::volatile_copy_nonoverlapping_memory => (
243 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
244 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
249 sym::write_bytes | sym::volatile_set_memory => (
252 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
258 sym::sqrtf32 => (0, vec![tcx.types.f32], tcx.types.f32),
259 sym::sqrtf64 => (0, vec![tcx.types.f64], tcx.types.f64),
260 sym::powif32 => (0, vec![tcx.types.f32, tcx.types.i32], tcx.types.f32),
261 sym::powif64 => (0, vec![tcx.types.f64, tcx.types.i32], tcx.types.f64),
262 sym::sinf32 => (0, vec![tcx.types.f32], tcx.types.f32),
263 sym::sinf64 => (0, vec![tcx.types.f64], tcx.types.f64),
264 sym::cosf32 => (0, vec![tcx.types.f32], tcx.types.f32),
265 sym::cosf64 => (0, vec![tcx.types.f64], tcx.types.f64),
266 sym::powf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
267 sym::powf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
268 sym::expf32 => (0, vec![tcx.types.f32], tcx.types.f32),
269 sym::expf64 => (0, vec![tcx.types.f64], tcx.types.f64),
270 sym::exp2f32 => (0, vec![tcx.types.f32], tcx.types.f32),
271 sym::exp2f64 => (0, vec![tcx.types.f64], tcx.types.f64),
272 sym::logf32 => (0, vec![tcx.types.f32], tcx.types.f32),
273 sym::logf64 => (0, vec![tcx.types.f64], tcx.types.f64),
274 sym::log10f32 => (0, vec![tcx.types.f32], tcx.types.f32),
275 sym::log10f64 => (0, vec![tcx.types.f64], tcx.types.f64),
276 sym::log2f32 => (0, vec![tcx.types.f32], tcx.types.f32),
277 sym::log2f64 => (0, vec![tcx.types.f64], tcx.types.f64),
278 sym::fmaf32 => (0, vec![tcx.types.f32, tcx.types.f32, tcx.types.f32], tcx.types.f32),
279 sym::fmaf64 => (0, vec![tcx.types.f64, tcx.types.f64, tcx.types.f64], tcx.types.f64),
280 sym::fabsf32 => (0, vec![tcx.types.f32], tcx.types.f32),
281 sym::fabsf64 => (0, vec![tcx.types.f64], tcx.types.f64),
282 sym::minnumf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
283 sym::minnumf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
284 sym::maxnumf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
285 sym::maxnumf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
286 sym::copysignf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
287 sym::copysignf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
288 sym::floorf32 => (0, vec![tcx.types.f32], tcx.types.f32),
289 sym::floorf64 => (0, vec![tcx.types.f64], tcx.types.f64),
290 sym::ceilf32 => (0, vec![tcx.types.f32], tcx.types.f32),
291 sym::ceilf64 => (0, vec![tcx.types.f64], tcx.types.f64),
292 sym::truncf32 => (0, vec![tcx.types.f32], tcx.types.f32),
293 sym::truncf64 => (0, vec![tcx.types.f64], tcx.types.f64),
294 sym::rintf32 => (0, vec![tcx.types.f32], tcx.types.f32),
295 sym::rintf64 => (0, vec![tcx.types.f64], tcx.types.f64),
296 sym::nearbyintf32 => (0, vec![tcx.types.f32], tcx.types.f32),
297 sym::nearbyintf64 => (0, vec![tcx.types.f64], tcx.types.f64),
298 sym::roundf32 => (0, vec![tcx.types.f32], tcx.types.f32),
299 sym::roundf64 => (0, vec![tcx.types.f64], tcx.types.f64),
301 sym::volatile_load | sym::unaligned_volatile_load => {
302 (1, vec![tcx.mk_imm_ptr(param(0))], param(0))
304 sym::volatile_store | sym::unaligned_volatile_store => {
305 (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit())
314 | sym::bitreverse => (1, vec![param(0)], param(0)),
316 sym::add_with_overflow | sym::sub_with_overflow | sym::mul_with_overflow => {
317 (1, vec![param(0), param(0)], tcx.intern_tup(&[param(0), tcx.types.bool]))
320 sym::ptr_guaranteed_cmp => {
321 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.u8)
324 sym::const_allocate => {
325 (0, vec![tcx.types.usize, tcx.types.usize], tcx.mk_mut_ptr(tcx.types.u8))
327 sym::const_deallocate => (
329 vec![tcx.mk_mut_ptr(tcx.types.u8), tcx.types.usize, tcx.types.usize],
333 sym::ptr_offset_from => {
334 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.isize)
336 sym::ptr_offset_from_unsigned => {
337 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.usize)
339 sym::unchecked_div | sym::unchecked_rem | sym::exact_div => {
340 (1, vec![param(0), param(0)], param(0))
342 sym::unchecked_shl | sym::unchecked_shr | sym::rotate_left | sym::rotate_right => {
343 (1, vec![param(0), param(0)], param(0))
345 sym::unchecked_add | sym::unchecked_sub | sym::unchecked_mul => {
346 (1, vec![param(0), param(0)], param(0))
348 sym::wrapping_add | sym::wrapping_sub | sym::wrapping_mul => {
349 (1, vec![param(0), param(0)], param(0))
351 sym::saturating_add | sym::saturating_sub => (1, vec![param(0), param(0)], param(0)),
352 sym::fadd_fast | sym::fsub_fast | sym::fmul_fast | sym::fdiv_fast | sym::frem_fast => {
353 (1, vec![param(0), param(0)], param(0))
355 sym::float_to_int_unchecked => (2, vec![param(0)], param(1)),
357 sym::assume => (0, vec![tcx.types.bool], tcx.mk_unit()),
358 sym::likely => (0, vec![tcx.types.bool], tcx.types.bool),
359 sym::unlikely => (0, vec![tcx.types.bool], tcx.types.bool),
361 sym::discriminant_value => {
362 let assoc_items = tcx.associated_item_def_ids(
363 tcx.require_lang_item(hir::LangItem::DiscriminantKind, None),
365 let discriminant_def_id = assoc_items[0];
367 let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) };
371 tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0)),
373 tcx.mk_projection(discriminant_def_id, tcx.mk_substs([param(0).into()].iter())),
378 let mut_u8 = tcx.mk_mut_ptr(tcx.types.u8);
379 let try_fn_ty = ty::Binder::dummy(tcx.mk_fn_sig(
383 hir::Unsafety::Normal,
386 let catch_fn_ty = ty::Binder::dummy(tcx.mk_fn_sig(
387 [mut_u8, mut_u8].iter().cloned(),
390 hir::Unsafety::Normal,
395 vec![tcx.mk_fn_ptr(try_fn_ty), mut_u8, tcx.mk_fn_ptr(catch_fn_ty)],
400 sym::va_start | sym::va_end => match mk_va_list_ty(hir::Mutability::Mut) {
401 Some((va_list_ref_ty, _)) => (0, vec![va_list_ref_ty], tcx.mk_unit()),
402 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
405 sym::va_copy => match mk_va_list_ty(hir::Mutability::Not) {
406 Some((va_list_ref_ty, va_list_ty)) => {
407 let va_list_ptr_ty = tcx.mk_mut_ptr(va_list_ty);
408 (0, vec![va_list_ptr_ty, va_list_ref_ty], tcx.mk_unit())
410 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
413 sym::va_arg => match mk_va_list_ty(hir::Mutability::Mut) {
414 Some((va_list_ref_ty, _)) => (1, vec![va_list_ref_ty], param(0)),
415 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
418 sym::nontemporal_store => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
421 let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) };
423 tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0));
424 (1, vec![param_ty; 2], tcx.types.bool)
427 sym::black_box => (1, vec![param(0)], param(0)),
429 sym::const_eval_select => (4, vec![param(0), param(1), param(2)], param(3)),
431 sym::vtable_size | sym::vtable_align => {
432 (0, vec![tcx.mk_imm_ptr(tcx.mk_unit())], tcx.types.usize)
436 tcx.sess.emit_err(UnrecognizedIntrinsicFunction { span: it.span, name: other });
440 (n_tps, 0, inputs, output, unsafety)
442 let sig = tcx.mk_fn_sig(inputs.into_iter(), output, false, unsafety, Abi::RustIntrinsic);
443 let sig = ty::Binder::bind_with_vars(sig, bound_vars);
444 equate_intrinsic_type(tcx, it, n_tps, n_lts, sig)
447 /// Type-check `extern "platform-intrinsic" { ... }` functions.
448 pub fn check_platform_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
450 let name = Symbol::intern(&format!("P{}", n));
451 tcx.mk_ty_param(n, name)
454 let name = it.ident.name;
456 let (n_tps, inputs, output) = match name {
457 sym::simd_eq | sym::simd_ne | sym::simd_lt | sym::simd_le | sym::simd_gt | sym::simd_ge => {
458 (2, vec![param(0), param(0)], param(1))
473 | sym::simd_saturating_add
474 | sym::simd_saturating_sub => (1, vec![param(0), param(0)], param(0)),
475 sym::simd_arith_offset => (2, vec![param(0), param(1)], param(0)),
489 | sym::simd_trunc => (1, vec![param(0)], param(0)),
490 sym::simd_fpowi => (1, vec![param(0), tcx.types.i32], param(0)),
491 sym::simd_fma => (1, vec![param(0), param(0), param(0)], param(0)),
492 sym::simd_gather => (3, vec![param(0), param(1), param(2)], param(0)),
493 sym::simd_scatter => (3, vec![param(0), param(1), param(2)], tcx.mk_unit()),
494 sym::simd_insert => (2, vec![param(0), tcx.types.u32, param(1)], param(0)),
495 sym::simd_extract => (2, vec![param(0), tcx.types.u32], param(1)),
499 | sym::simd_expose_addr
500 | sym::simd_from_exposed_addr => (2, vec![param(0)], param(1)),
501 sym::simd_bitmask => (2, vec![param(0)], param(1)),
502 sym::simd_select | sym::simd_select_bitmask => {
503 (2, vec![param(0), param(1), param(1)], param(1))
505 sym::simd_reduce_all | sym::simd_reduce_any => (1, vec![param(0)], tcx.types.bool),
506 sym::simd_reduce_add_ordered | sym::simd_reduce_mul_ordered => {
507 (2, vec![param(0), param(1)], param(1))
509 sym::simd_reduce_add_unordered
510 | sym::simd_reduce_mul_unordered
511 | sym::simd_reduce_and
512 | sym::simd_reduce_or
513 | sym::simd_reduce_xor
514 | sym::simd_reduce_min
515 | sym::simd_reduce_max
516 | sym::simd_reduce_min_nanless
517 | sym::simd_reduce_max_nanless => (2, vec![param(0)], param(1)),
518 sym::simd_shuffle => (3, vec![param(0), param(0), param(1)], param(2)),
519 name if name.as_str().starts_with("simd_shuffle") => {
520 match name.as_str()["simd_shuffle".len()..].parse() {
522 let params = vec![param(0), param(0), tcx.mk_array(tcx.types.u32, n)];
523 (2, params, param(1))
527 format!("unrecognized platform-specific intrinsic function: `{name}`");
528 tcx.sess.struct_span_err(it.span, &msg).emit();
534 let msg = format!("unrecognized platform-specific intrinsic function: `{name}`");
535 tcx.sess.struct_span_err(it.span, &msg).emit();
540 let sig = tcx.mk_fn_sig(
544 hir::Unsafety::Unsafe,
545 Abi::PlatformIntrinsic,
547 let sig = ty::Binder::dummy(sig);
548 equate_intrinsic_type(tcx, it, n_tps, 0, sig)