1 //! Type-checking for the rust-intrinsic and platform-intrinsic
2 //! intrinsics that the compiler exposes.
5 SimdShuffleMissingLength, UnrecognizedAtomicOperation, UnrecognizedIntrinsicFunction,
6 WrongNumberOfGenericArgumentsToIntrinsic,
8 use crate::require_same_types;
10 use rustc_errors::{pluralize, 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 {
46 expected_pluralize: pluralize!(expected),
55 if gen_count_ok(own_counts.lifetimes, n_lts, "lifetime")
56 && gen_count_ok(own_counts.types, n_tps, "type")
57 && gen_count_ok(own_counts.consts, 0, "const")
59 let fty = tcx.mk_fn_ptr(sig);
60 let cause = ObligationCause::new(it.span, it.hir_id(), ObligationCauseCode::IntrinsicType);
61 require_same_types(tcx, &cause, tcx.mk_fn_ptr(tcx.fn_sig(it.def_id)), fty);
65 /// Returns the unsafety of the given intrinsic.
66 pub fn intrinsic_operation_unsafety(intrinsic: Symbol) -> hir::Unsafety {
68 // When adding a new intrinsic to this list,
69 // it's usually worth updating that intrinsic's documentation
70 // to note that it's safe to call, since
71 // safe extern fns are otherwise unprecedented.
76 | sym::caller_location
77 | sym::add_with_overflow
78 | sym::sub_with_overflow
79 | sym::mul_with_overflow
92 | sym::discriminant_value
96 | sym::ptr_guaranteed_eq
97 | sym::ptr_guaranteed_ne
106 | sym::variant_count => hir::Unsafety::Normal,
107 _ => hir::Unsafety::Unsafe,
111 /// Remember to add all intrinsics here, in `compiler/rustc_codegen_llvm/src/intrinsic.rs`,
112 /// and in `library/core/src/intrinsics.rs`.
113 pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
114 let param = |n| tcx.mk_ty_param(n, Symbol::intern(&format!("P{}", n)));
115 let intrinsic_name = tcx.item_name(it.def_id.to_def_id());
116 let name_str = intrinsic_name.as_str();
118 let bound_vars = tcx.mk_bound_variable_kinds(
119 [ty::BoundVariableKind::Region(ty::BrAnon(0)), ty::BoundVariableKind::Region(ty::BrEnv)]
123 let mk_va_list_ty = |mutbl| {
124 tcx.lang_items().va_list().map(|did| {
125 let region = tcx.mk_region(ty::ReLateBound(
127 ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) },
129 let env_region = tcx.mk_region(ty::ReLateBound(
131 ty::BoundRegion { var: ty::BoundVar::from_u32(1), kind: ty::BrEnv },
133 let va_list_ty = tcx.type_of(did).subst(tcx, &[region.into()]);
134 (tcx.mk_ref(env_region, ty::TypeAndMut { ty: va_list_ty, mutbl }), va_list_ty)
138 let (n_tps, n_lts, inputs, output, unsafety) = if name_str.starts_with("atomic_") {
139 let split: Vec<&str> = name_str.split('_').collect();
140 assert!(split.len() >= 2, "Atomic intrinsic in an incorrect format");
142 //We only care about the operation here
143 let (n_tps, inputs, output) = match split[1] {
144 "cxchg" | "cxchgweak" => (
146 vec![tcx.mk_mut_ptr(param(0)), param(0), param(0)],
147 tcx.intern_tup(&[param(0), tcx.types.bool]),
149 "load" => (1, vec![tcx.mk_imm_ptr(param(0))], param(0)),
150 "store" => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
152 "xchg" | "xadd" | "xsub" | "and" | "nand" | "or" | "xor" | "max" | "min" | "umax"
153 | "umin" => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], param(0)),
154 "fence" | "singlethreadfence" => (0, Vec::new(), tcx.mk_unit()),
156 tcx.sess.emit_err(UnrecognizedAtomicOperation { span: it.span, op });
160 (n_tps, 0, inputs, output, hir::Unsafety::Unsafe)
162 let unsafety = intrinsic_operation_unsafety(intrinsic_name);
163 let (n_tps, inputs, output) = match intrinsic_name {
164 sym::abort => (0, Vec::new(), tcx.types.never),
165 sym::unreachable => (0, Vec::new(), tcx.types.never),
166 sym::breakpoint => (0, Vec::new(), tcx.mk_unit()),
167 sym::size_of | sym::pref_align_of | sym::min_align_of | sym::variant_count => {
168 (1, Vec::new(), tcx.types.usize)
170 sym::size_of_val | sym::min_align_of_val => {
171 (1, vec![tcx.mk_imm_ptr(param(0))], tcx.types.usize)
173 sym::rustc_peek => (1, vec![param(0)], param(0)),
174 sym::caller_location => (0, vec![], tcx.caller_location_ty()),
175 sym::assert_inhabited | sym::assert_zero_valid | sym::assert_uninit_valid => {
176 (1, Vec::new(), tcx.mk_unit())
178 sym::forget => (1, vec![param(0)], tcx.mk_unit()),
179 sym::transmute => (2, vec![param(0)], param(1)),
180 sym::prefetch_read_data
181 | sym::prefetch_write_data
182 | sym::prefetch_read_instruction
183 | sym::prefetch_write_instruction => (
186 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
191 sym::drop_in_place => (1, vec![tcx.mk_mut_ptr(param(0))], tcx.mk_unit()),
192 sym::needs_drop => (1, Vec::new(), tcx.types.bool),
194 sym::type_name => (1, Vec::new(), tcx.mk_static_str()),
195 sym::type_id => (1, Vec::new(), tcx.types.u64),
196 sym::offset | sym::arith_offset => (
199 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
202 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
204 sym::copy | sym::copy_nonoverlapping => (
207 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
208 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
213 sym::volatile_copy_memory | sym::volatile_copy_nonoverlapping_memory => (
216 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
217 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Not }),
222 sym::write_bytes | sym::volatile_set_memory => (
225 tcx.mk_ptr(ty::TypeAndMut { ty: param(0), mutbl: hir::Mutability::Mut }),
231 sym::sqrtf32 => (0, vec![tcx.types.f32], tcx.types.f32),
232 sym::sqrtf64 => (0, vec![tcx.types.f64], tcx.types.f64),
233 sym::powif32 => (0, vec![tcx.types.f32, tcx.types.i32], tcx.types.f32),
234 sym::powif64 => (0, vec![tcx.types.f64, tcx.types.i32], tcx.types.f64),
235 sym::sinf32 => (0, vec![tcx.types.f32], tcx.types.f32),
236 sym::sinf64 => (0, vec![tcx.types.f64], tcx.types.f64),
237 sym::cosf32 => (0, vec![tcx.types.f32], tcx.types.f32),
238 sym::cosf64 => (0, vec![tcx.types.f64], tcx.types.f64),
239 sym::powf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
240 sym::powf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
241 sym::expf32 => (0, vec![tcx.types.f32], tcx.types.f32),
242 sym::expf64 => (0, vec![tcx.types.f64], tcx.types.f64),
243 sym::exp2f32 => (0, vec![tcx.types.f32], tcx.types.f32),
244 sym::exp2f64 => (0, vec![tcx.types.f64], tcx.types.f64),
245 sym::logf32 => (0, vec![tcx.types.f32], tcx.types.f32),
246 sym::logf64 => (0, vec![tcx.types.f64], tcx.types.f64),
247 sym::log10f32 => (0, vec![tcx.types.f32], tcx.types.f32),
248 sym::log10f64 => (0, vec![tcx.types.f64], tcx.types.f64),
249 sym::log2f32 => (0, vec![tcx.types.f32], tcx.types.f32),
250 sym::log2f64 => (0, vec![tcx.types.f64], tcx.types.f64),
251 sym::fmaf32 => (0, vec![tcx.types.f32, tcx.types.f32, tcx.types.f32], tcx.types.f32),
252 sym::fmaf64 => (0, vec![tcx.types.f64, tcx.types.f64, tcx.types.f64], tcx.types.f64),
253 sym::fabsf32 => (0, vec![tcx.types.f32], tcx.types.f32),
254 sym::fabsf64 => (0, vec![tcx.types.f64], tcx.types.f64),
255 sym::minnumf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
256 sym::minnumf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
257 sym::maxnumf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
258 sym::maxnumf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
259 sym::copysignf32 => (0, vec![tcx.types.f32, tcx.types.f32], tcx.types.f32),
260 sym::copysignf64 => (0, vec![tcx.types.f64, tcx.types.f64], tcx.types.f64),
261 sym::floorf32 => (0, vec![tcx.types.f32], tcx.types.f32),
262 sym::floorf64 => (0, vec![tcx.types.f64], tcx.types.f64),
263 sym::ceilf32 => (0, vec![tcx.types.f32], tcx.types.f32),
264 sym::ceilf64 => (0, vec![tcx.types.f64], tcx.types.f64),
265 sym::truncf32 => (0, vec![tcx.types.f32], tcx.types.f32),
266 sym::truncf64 => (0, vec![tcx.types.f64], tcx.types.f64),
267 sym::rintf32 => (0, vec![tcx.types.f32], tcx.types.f32),
268 sym::rintf64 => (0, vec![tcx.types.f64], tcx.types.f64),
269 sym::nearbyintf32 => (0, vec![tcx.types.f32], tcx.types.f32),
270 sym::nearbyintf64 => (0, vec![tcx.types.f64], tcx.types.f64),
271 sym::roundf32 => (0, vec![tcx.types.f32], tcx.types.f32),
272 sym::roundf64 => (0, vec![tcx.types.f64], tcx.types.f64),
274 sym::volatile_load | sym::unaligned_volatile_load => {
275 (1, vec![tcx.mk_imm_ptr(param(0))], param(0))
277 sym::volatile_store | sym::unaligned_volatile_store => {
278 (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit())
287 | sym::bitreverse => (1, vec![param(0)], param(0)),
289 sym::add_with_overflow | sym::sub_with_overflow | sym::mul_with_overflow => {
290 (1, vec![param(0), param(0)], tcx.intern_tup(&[param(0), tcx.types.bool]))
293 sym::ptr_guaranteed_eq | sym::ptr_guaranteed_ne => {
294 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.bool)
297 sym::const_allocate => {
298 (0, vec![tcx.types.usize, tcx.types.usize], tcx.mk_mut_ptr(tcx.types.u8))
301 sym::ptr_offset_from => {
302 (1, vec![tcx.mk_imm_ptr(param(0)), tcx.mk_imm_ptr(param(0))], tcx.types.isize)
304 sym::unchecked_div | sym::unchecked_rem | sym::exact_div => {
305 (1, vec![param(0), param(0)], param(0))
307 sym::unchecked_shl | sym::unchecked_shr | sym::rotate_left | sym::rotate_right => {
308 (1, vec![param(0), param(0)], param(0))
310 sym::unchecked_add | sym::unchecked_sub | sym::unchecked_mul => {
311 (1, vec![param(0), param(0)], param(0))
313 sym::wrapping_add | sym::wrapping_sub | sym::wrapping_mul => {
314 (1, vec![param(0), param(0)], param(0))
316 sym::saturating_add | sym::saturating_sub => (1, vec![param(0), param(0)], param(0)),
317 sym::fadd_fast | sym::fsub_fast | sym::fmul_fast | sym::fdiv_fast | sym::frem_fast => {
318 (1, vec![param(0), param(0)], param(0))
320 sym::float_to_int_unchecked => (2, vec![param(0)], param(1)),
322 sym::assume => (0, vec![tcx.types.bool], tcx.mk_unit()),
323 sym::likely => (0, vec![tcx.types.bool], tcx.types.bool),
324 sym::unlikely => (0, vec![tcx.types.bool], tcx.types.bool),
326 sym::discriminant_value => {
328 tcx.associated_items(tcx.lang_items().discriminant_kind_trait().unwrap());
329 let discriminant_def_id = assoc_items.in_definition_order().next().unwrap().def_id;
331 let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) };
335 tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0)),
337 tcx.mk_projection(discriminant_def_id, tcx.mk_substs([param(0).into()].iter())),
342 let mut_u8 = tcx.mk_mut_ptr(tcx.types.u8);
343 let try_fn_ty = ty::Binder::dummy(tcx.mk_fn_sig(
347 hir::Unsafety::Normal,
350 let catch_fn_ty = ty::Binder::dummy(tcx.mk_fn_sig(
351 [mut_u8, mut_u8].iter().cloned(),
354 hir::Unsafety::Normal,
359 vec![tcx.mk_fn_ptr(try_fn_ty), mut_u8, tcx.mk_fn_ptr(catch_fn_ty)],
364 sym::va_start | sym::va_end => match mk_va_list_ty(hir::Mutability::Mut) {
365 Some((va_list_ref_ty, _)) => (0, vec![va_list_ref_ty], tcx.mk_unit()),
366 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
369 sym::va_copy => match mk_va_list_ty(hir::Mutability::Not) {
370 Some((va_list_ref_ty, va_list_ty)) => {
371 let va_list_ptr_ty = tcx.mk_mut_ptr(va_list_ty);
372 (0, vec![va_list_ptr_ty, va_list_ref_ty], tcx.mk_unit())
374 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
377 sym::va_arg => match mk_va_list_ty(hir::Mutability::Mut) {
378 Some((va_list_ref_ty, _)) => (1, vec![va_list_ref_ty], param(0)),
379 None => bug!("`va_list` language item needed for C-variadic intrinsics"),
382 sym::nontemporal_store => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
385 let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) };
387 tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0));
388 (1, vec![param_ty; 2], tcx.types.bool)
391 sym::black_box => (1, vec![param(0)], param(0)),
394 tcx.sess.emit_err(UnrecognizedIntrinsicFunction { span: it.span, name: other });
398 (n_tps, 0, inputs, output, unsafety)
400 let sig = tcx.mk_fn_sig(inputs.into_iter(), output, false, unsafety, Abi::RustIntrinsic);
401 let sig = ty::Binder::bind_with_vars(sig, bound_vars);
402 equate_intrinsic_type(tcx, it, n_tps, n_lts, sig)
405 /// Type-check `extern "platform-intrinsic" { ... }` functions.
406 pub fn check_platform_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
408 let name = Symbol::intern(&format!("P{}", n));
409 tcx.mk_ty_param(n, name)
412 let name = it.ident.name;
414 let (n_tps, inputs, output) = match name {
415 sym::simd_eq | sym::simd_ne | sym::simd_lt | sym::simd_le | sym::simd_gt | sym::simd_ge => {
416 (2, vec![param(0), param(0)], param(1))
431 | sym::simd_saturating_add
432 | sym::simd_saturating_sub => (1, vec![param(0), param(0)], param(0)),
446 | sym::simd_trunc => (1, vec![param(0)], param(0)),
447 sym::simd_fpowi => (1, vec![param(0), tcx.types.i32], param(0)),
448 sym::simd_fma => (1, vec![param(0), param(0), param(0)], param(0)),
449 sym::simd_gather => (3, vec![param(0), param(1), param(2)], param(0)),
450 sym::simd_scatter => (3, vec![param(0), param(1), param(2)], tcx.mk_unit()),
451 sym::simd_insert => (2, vec![param(0), tcx.types.u32, param(1)], param(0)),
452 sym::simd_extract => (2, vec![param(0), tcx.types.u32], param(1)),
453 sym::simd_cast => (2, vec![param(0)], param(1)),
454 sym::simd_bitmask => (2, vec![param(0)], param(1)),
455 sym::simd_select | sym::simd_select_bitmask => {
456 (2, vec![param(0), param(1), param(1)], param(1))
458 sym::simd_reduce_all | sym::simd_reduce_any => (1, vec![param(0)], tcx.types.bool),
459 sym::simd_reduce_add_ordered | sym::simd_reduce_mul_ordered => {
460 (2, vec![param(0), param(1)], param(1))
462 sym::simd_reduce_add_unordered
463 | sym::simd_reduce_mul_unordered
464 | sym::simd_reduce_and
465 | sym::simd_reduce_or
466 | sym::simd_reduce_xor
467 | sym::simd_reduce_min
468 | sym::simd_reduce_max
469 | sym::simd_reduce_min_nanless
470 | sym::simd_reduce_max_nanless => (2, vec![param(0)], param(1)),
471 name if name.as_str().starts_with("simd_shuffle") => {
472 match name.as_str()["simd_shuffle".len()..].parse() {
474 let params = vec![param(0), param(0), tcx.mk_array(tcx.types.u32, n)];
475 (2, params, param(1))
478 tcx.sess.emit_err(SimdShuffleMissingLength { span: it.span, name });
484 let msg = format!("unrecognized platform-specific intrinsic function: `{}`", name);
485 tcx.sess.struct_span_err(it.span, &msg).emit();
490 let sig = tcx.mk_fn_sig(
494 hir::Unsafety::Unsafe,
495 Abi::PlatformIntrinsic,
497 let sig = ty::Binder::dummy(sig);
498 equate_intrinsic_type(tcx, it, n_tps, 0, sig)