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 rustc_errors::struct_span_err;
12 use rustc_middle::traits::{ObligationCause, ObligationCauseCode};
13 use rustc_middle::ty::subst::Subst;
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(intrinsic: Symbol) -> hir::Unsafety {
67 // When adding a new intrinsic to this list,
68 // it's usually worth updating that intrinsic's documentation
69 // to note that it's safe to call, since
70 // safe extern fns are otherwise unprecedented.
72 | sym::assert_inhabited
73 | sym::assert_zero_valid
74 | sym::assert_uninit_valid
78 | sym::caller_location
79 | sym::add_with_overflow
80 | sym::sub_with_overflow
81 | sym::mul_with_overflow
94 | sym::discriminant_value
98 | sym::ptr_guaranteed_eq
99 | sym::ptr_guaranteed_ne
109 | sym::ptr_mask => hir::Unsafety::Normal,
110 _ => hir::Unsafety::Unsafe,
114 /// Remember to add all intrinsics here, in `compiler/rustc_codegen_llvm/src/intrinsic.rs`,
115 /// and in `library/core/src/intrinsics.rs`.
116 pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
117 let param = |n| tcx.mk_ty_param(n, Symbol::intern(&format!("P{}", n)));
118 let intrinsic_name = tcx.item_name(it.def_id.to_def_id());
119 let name_str = intrinsic_name.as_str();
121 let bound_vars = tcx.mk_bound_variable_kinds(
122 [ty::BoundVariableKind::Region(ty::BrAnon(0)), ty::BoundVariableKind::Region(ty::BrEnv)]
126 let mk_va_list_ty = |mutbl| {
127 tcx.lang_items().va_list().map(|did| {
128 let region = tcx.mk_region(ty::ReLateBound(
130 ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) },
132 let env_region = tcx.mk_region(ty::ReLateBound(
134 ty::BoundRegion { var: ty::BoundVar::from_u32(1), kind: ty::BrEnv },
136 let va_list_ty = tcx.bound_type_of(did).subst(tcx, &[region.into()]);
137 (tcx.mk_ref(env_region, ty::TypeAndMut { ty: va_list_ty, mutbl }), va_list_ty)
141 let (n_tps, n_lts, inputs, output, unsafety) = if name_str.starts_with("atomic_") {
142 let split: Vec<&str> = name_str.split('_').collect();
143 assert!(split.len() >= 2, "Atomic intrinsic in an incorrect format");
145 //We only care about the operation here
146 let (n_tps, inputs, output) = match split[1] {
147 "cxchg" | "cxchgweak" => (
149 vec![tcx.mk_mut_ptr(param(0)), param(0), param(0)],
150 tcx.intern_tup(&[param(0), tcx.types.bool]),
152 "load" => (1, vec![tcx.mk_imm_ptr(param(0))], param(0)),
153 "store" => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
155 "xchg" | "xadd" | "xsub" | "and" | "nand" | "or" | "xor" | "max" | "min" | "umax"
156 | "umin" => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], param(0)),
157 "fence" | "singlethreadfence" => (0, Vec::new(), tcx.mk_unit()),
159 tcx.sess.emit_err(UnrecognizedAtomicOperation { span: it.span, op });
163 (n_tps, 0, inputs, output, hir::Unsafety::Unsafe)
165 let unsafety = intrinsic_operation_unsafety(intrinsic_name);
166 let (n_tps, inputs, output) = match intrinsic_name {
167 sym::abort => (0, Vec::new(), tcx.types.never),
168 sym::unreachable => (0, Vec::new(), tcx.types.never),
169 sym::breakpoint => (0, Vec::new(), tcx.mk_unit()),
170 sym::size_of | sym::pref_align_of | sym::min_align_of | sym::variant_count => {
171 (1, Vec::new(), tcx.types.usize)
173 sym::size_of_val | sym::min_align_of_val => {
174 (1, vec![tcx.mk_imm_ptr(param(0))], tcx.types.usize)
176 sym::rustc_peek => (1, vec![param(0)], param(0)),
177 sym::caller_location => (0, vec![], tcx.caller_location_ty()),
178 sym::assert_inhabited | sym::assert_zero_valid | sym::assert_uninit_valid => {
179 (1, Vec::new(), tcx.mk_unit())
181 sym::forget => (1, vec![param(0)], tcx.mk_unit()),
182 sym::transmute => (2, vec![param(0)], param(1)),
183 sym::prefetch_read_data
184 | sym::prefetch_write_data
185 | sym::prefetch_read_instruction
186 | sym::prefetch_write_instruction => (
189 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
194 sym::drop_in_place => (1, vec![tcx.mk_mut_ptr(param(0))], tcx.mk_unit()),
195 sym::needs_drop => (1, Vec::new(), tcx.types.bool),
197 sym::type_name => (1, Vec::new(), tcx.mk_static_str()),
198 sym::type_id => (1, Vec::new(), tcx.types.u64),
199 sym::offset | sym::arith_offset => (
202 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
205 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
210 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
213 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
216 sym::copy | sym::copy_nonoverlapping => (
219 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
220 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
225 sym::volatile_copy_memory | sym::volatile_copy_nonoverlapping_memory => (
228 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
229 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
234 sym::write_bytes | sym::volatile_set_memory => (
237 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
243 sym::sqrtf32 => (0, vec![tcx.types.f32], tcx.types.f32),
244 sym::sqrtf64 => (0, vec![tcx.types.f64], tcx.types.f64),
245 sym::powif32 => (0, vec![tcx.types.f32, tcx.types.i32], tcx.types.f32),
246 sym::powif64 => (0, vec![tcx.types.f64, tcx.types.i32], tcx.types.f64),
247 sym::sinf32 => (0, vec![tcx.types.f32], tcx.types.f32),
248 sym::sinf64 => (0, vec![tcx.types.f64], tcx.types.f64),
249 sym::cosf32 => (0, vec![tcx.types.f32], tcx.types.f32),
250 sym::cosf64 => (0, vec![tcx.types.f64], tcx.types.f64),
251 sym::powf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
252 sym::powf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
253 sym::expf32 => (0, vec![tcx.types.f32], tcx.types.f32),
254 sym::expf64 => (0, vec![tcx.types.f64], tcx.types.f64),
255 sym::exp2f32 => (0, vec![tcx.types.f32], tcx.types.f32),
256 sym::exp2f64 => (0, vec![tcx.types.f64], tcx.types.f64),
257 sym::logf32 => (0, vec![tcx.types.f32], tcx.types.f32),
258 sym::logf64 => (0, vec![tcx.types.f64], tcx.types.f64),
259 sym::log10f32 => (0, vec![tcx.types.f32], tcx.types.f32),
260 sym::log10f64 => (0, vec![tcx.types.f64], tcx.types.f64),
261 sym::log2f32 => (0, vec![tcx.types.f32], tcx.types.f32),
262 sym::log2f64 => (0, vec![tcx.types.f64], tcx.types.f64),
263 sym::fmaf32 => (0, vec![tcx.types.f32, tcx.types.f32, tcx.types.f32], tcx.types.f32),
264 sym::fmaf64 => (0, vec![tcx.types.f64, tcx.types.f64, tcx.types.f64], tcx.types.f64),
265 sym::fabsf32 => (0, vec![tcx.types.f32], tcx.types.f32),
266 sym::fabsf64 => (0, vec![tcx.types.f64], tcx.types.f64),
267 sym::minnumf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
268 sym::minnumf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
269 sym::maxnumf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
270 sym::maxnumf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
271 sym::copysignf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
272 sym::copysignf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
273 sym::floorf32 => (0, vec![tcx.types.f32], tcx.types.f32),
274 sym::floorf64 => (0, vec![tcx.types.f64], tcx.types.f64),
275 sym::ceilf32 => (0, vec![tcx.types.f32], tcx.types.f32),
276 sym::ceilf64 => (0, vec![tcx.types.f64], tcx.types.f64),
277 sym::truncf32 => (0, vec![tcx.types.f32], tcx.types.f32),
278 sym::truncf64 => (0, vec![tcx.types.f64], tcx.types.f64),
279 sym::rintf32 => (0, vec![tcx.types.f32], tcx.types.f32),
280 sym::rintf64 => (0, vec![tcx.types.f64], tcx.types.f64),
281 sym::nearbyintf32 => (0, vec![tcx.types.f32], tcx.types.f32),
282 sym::nearbyintf64 => (0, vec![tcx.types.f64], tcx.types.f64),
283 sym::roundf32 => (0, vec![tcx.types.f32], tcx.types.f32),
284 sym::roundf64 => (0, vec![tcx.types.f64], tcx.types.f64),
286 sym::volatile_load | sym::unaligned_volatile_load => {
287 (1, vec![tcx.mk_imm_ptr(param(0))], param(0))
289 sym::volatile_store | sym::unaligned_volatile_store => {
290 (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit())
299 | sym::bitreverse => (1, vec![param(0)], param(0)),
301 sym::add_with_overflow | sym::sub_with_overflow | sym::mul_with_overflow => {
302 (1, vec![param(0), param(0)], tcx.intern_tup(&[param(0), tcx.types.bool]))
305 sym::ptr_guaranteed_eq | sym::ptr_guaranteed_ne => {
306 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.bool)
309 sym::const_allocate => {
310 (0, vec![tcx.types.usize, tcx.types.usize], tcx.mk_mut_ptr(tcx.types.u8))
312 sym::const_deallocate => (
314 vec![tcx.mk_mut_ptr(tcx.types.u8), tcx.types.usize, tcx.types.usize],
318 sym::ptr_offset_from => {
319 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.isize)
321 sym::ptr_offset_from_unsigned => {
322 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.usize)
324 sym::unchecked_div | sym::unchecked_rem | sym::exact_div => {
325 (1, vec![param(0), param(0)], param(0))
327 sym::unchecked_shl | sym::unchecked_shr | sym::rotate_left | sym::rotate_right => {
328 (1, vec![param(0), param(0)], param(0))
330 sym::unchecked_add | sym::unchecked_sub | sym::unchecked_mul => {
331 (1, vec![param(0), param(0)], param(0))
333 sym::wrapping_add | sym::wrapping_sub | sym::wrapping_mul => {
334 (1, vec![param(0), param(0)], param(0))
336 sym::saturating_add | sym::saturating_sub => (1, vec![param(0), param(0)], param(0)),
337 sym::fadd_fast | sym::fsub_fast | sym::fmul_fast | sym::fdiv_fast | sym::frem_fast => {
338 (1, vec![param(0), param(0)], param(0))
340 sym::float_to_int_unchecked => (2, vec![param(0)], param(1)),
342 sym::assume => (0, vec![tcx.types.bool], tcx.mk_unit()),
343 sym::likely => (0, vec![tcx.types.bool], tcx.types.bool),
344 sym::unlikely => (0, vec![tcx.types.bool], tcx.types.bool),
346 sym::discriminant_value => {
347 let assoc_items = tcx.associated_item_def_ids(
348 tcx.require_lang_item(hir::LangItem::DiscriminantKind, None),
350 let discriminant_def_id = assoc_items[0];
352 let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) };
356 tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0)),
358 tcx.mk_projection(discriminant_def_id, tcx.mk_substs([param(0).into()].iter())),
363 let mut_u8 = tcx.mk_mut_ptr(tcx.types.u8);
364 let try_fn_ty = ty::Binder::dummy(tcx.mk_fn_sig(
368 hir::Unsafety::Normal,
371 let catch_fn_ty = ty::Binder::dummy(tcx.mk_fn_sig(
372 [mut_u8, mut_u8].iter().cloned(),
375 hir::Unsafety::Normal,
380 vec![tcx.mk_fn_ptr(try_fn_ty), mut_u8, tcx.mk_fn_ptr(catch_fn_ty)],
385 sym::va_start | sym::va_end => match mk_va_list_ty(hir::Mutability::Mut) {
386 Some((va_list_ref_ty, _)) => (0, vec![va_list_ref_ty], tcx.mk_unit()),
387 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
390 sym::va_copy => match mk_va_list_ty(hir::Mutability::Not) {
391 Some((va_list_ref_ty, va_list_ty)) => {
392 let va_list_ptr_ty = tcx.mk_mut_ptr(va_list_ty);
393 (0, vec![va_list_ptr_ty, va_list_ref_ty], tcx.mk_unit())
395 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
398 sym::va_arg => match mk_va_list_ty(hir::Mutability::Mut) {
399 Some((va_list_ref_ty, _)) => (1, vec![va_list_ref_ty], param(0)),
400 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
403 sym::nontemporal_store => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
406 let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) };
408 tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0));
409 (1, vec![param_ty; 2], tcx.types.bool)
412 sym::black_box => (1, vec![param(0)], param(0)),
414 sym::const_eval_select => (4, vec![param(0), param(1), param(2)], param(3)),
416 sym::vtable_size | sym::vtable_align => {
417 (0, vec![tcx.mk_imm_ptr(tcx.mk_unit())], tcx.types.usize)
421 tcx.sess.emit_err(UnrecognizedIntrinsicFunction { span: it.span, name: other });
425 (n_tps, 0, inputs, output, unsafety)
427 let sig = tcx.mk_fn_sig(inputs.into_iter(), output, false, unsafety, Abi::RustIntrinsic);
428 let sig = ty::Binder::bind_with_vars(sig, bound_vars);
429 equate_intrinsic_type(tcx, it, n_tps, n_lts, sig)
432 /// Type-check `extern "platform-intrinsic" { ... }` functions.
433 pub fn check_platform_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
435 let name = Symbol::intern(&format!("P{}", n));
436 tcx.mk_ty_param(n, name)
439 let name = it.ident.name;
441 let (n_tps, inputs, output) = match name {
442 sym::simd_eq | sym::simd_ne | sym::simd_lt | sym::simd_le | sym::simd_gt | sym::simd_ge => {
443 (2, vec![param(0), param(0)], param(1))
458 | sym::simd_saturating_add
459 | sym::simd_saturating_sub => (1, vec![param(0), param(0)], param(0)),
460 sym::simd_arith_offset => (2, vec![param(0), param(1)], param(0)),
474 | sym::simd_trunc => (1, vec![param(0)], param(0)),
475 sym::simd_fpowi => (1, vec![param(0), tcx.types.i32], param(0)),
476 sym::simd_fma => (1, vec![param(0), param(0), param(0)], param(0)),
477 sym::simd_gather => (3, vec![param(0), param(1), param(2)], param(0)),
478 sym::simd_scatter => (3, vec![param(0), param(1), param(2)], tcx.mk_unit()),
479 sym::simd_insert => (2, vec![param(0), tcx.types.u32, param(1)], param(0)),
480 sym::simd_extract => (2, vec![param(0), tcx.types.u32], param(1)),
481 sym::simd_cast | sym::simd_as => (2, vec![param(0)], param(1)),
482 sym::simd_bitmask => (2, vec![param(0)], param(1)),
483 sym::simd_select | sym::simd_select_bitmask => {
484 (2, vec![param(0), param(1), param(1)], param(1))
486 sym::simd_reduce_all | sym::simd_reduce_any => (1, vec![param(0)], tcx.types.bool),
487 sym::simd_reduce_add_ordered | sym::simd_reduce_mul_ordered => {
488 (2, vec![param(0), param(1)], param(1))
490 sym::simd_reduce_add_unordered
491 | sym::simd_reduce_mul_unordered
492 | sym::simd_reduce_and
493 | sym::simd_reduce_or
494 | sym::simd_reduce_xor
495 | sym::simd_reduce_min
496 | sym::simd_reduce_max
497 | sym::simd_reduce_min_nanless
498 | sym::simd_reduce_max_nanless => (2, vec![param(0)], param(1)),
499 sym::simd_shuffle => (3, vec![param(0), param(0), param(1)], param(2)),
500 name if name.as_str().starts_with("simd_shuffle") => {
501 match name.as_str()["simd_shuffle".len()..].parse() {
503 let params = vec![param(0), param(0), tcx.mk_array(tcx.types.u32, n)];
504 (2, params, param(1))
508 format!("unrecognized platform-specific intrinsic function: `{name}`");
509 tcx.sess.struct_span_err(it.span, &msg).emit();
515 let msg = format!("unrecognized platform-specific intrinsic function: `{name}`");
516 tcx.sess.struct_span_err(it.span, &msg).emit();
521 let sig = tcx.mk_fn_sig(
525 hir::Unsafety::Unsafe,
526 Abi::PlatformIntrinsic,
528 let sig = ty::Binder::dummy(sig);
529 equate_intrinsic_type(tcx, it, n_tps, 0, sig)