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1a4d82fc JJ |
1 | // Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT |
2 | // file at the top-level directory of this distribution and at | |
3 | // http://rust-lang.org/COPYRIGHT. | |
4 | // | |
5 | // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or | |
6 | // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license | |
7 | // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your | |
8 | // option. This file may not be copied, modified, or distributed | |
9 | // except according to those terms. | |
10 | ||
11 | #![allow(non_camel_case_types)] | |
12 | ||
54a0048b | 13 | use rustc::hir::def_id::DefId; |
54a0048b SL |
14 | use rustc::ty::subst; |
15 | use abi::FnType; | |
16 | use adt; | |
17 | use common::*; | |
18 | use machine; | |
5bcae85e | 19 | use rustc::traits::Reveal; |
54a0048b SL |
20 | use rustc::ty::{self, Ty, TypeFoldable}; |
21 | ||
22 | use type_::Type; | |
23 | ||
b039eaaf | 24 | use syntax::ast; |
1a4d82fc JJ |
25 | |
26 | // LLVM doesn't like objects that are too big. Issue #17913 | |
27 | fn ensure_array_fits_in_address_space<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, | |
28 | llet: Type, | |
29 | size: machine::llsize, | |
30 | scapegoat: Ty<'tcx>) { | |
31 | let esz = machine::llsize_of_alloc(ccx, llet); | |
32 | match esz.checked_mul(size) { | |
33 | Some(n) if n < ccx.obj_size_bound() => {} | |
34 | _ => { ccx.report_overbig_object(scapegoat) } | |
35 | } | |
36 | } | |
37 | ||
1a4d82fc JJ |
38 | // A "sizing type" is an LLVM type, the size and alignment of which are |
39 | // guaranteed to be equivalent to what you would get out of `type_of()`. It's | |
40 | // useful because: | |
41 | // | |
42 | // (1) It may be cheaper to compute the sizing type than the full type if all | |
43 | // you're interested in is the size and/or alignment; | |
44 | // | |
45 | // (2) It won't make any recursive calls to determine the structure of the | |
46 | // type behind pointers. This can help prevent infinite loops for | |
47 | // recursive types. For example, enum types rely on this behavior. | |
48 | ||
49 | pub fn sizing_type_of<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>, t: Ty<'tcx>) -> Type { | |
7453a54e SL |
50 | if let Some(t) = cx.llsizingtypes().borrow().get(&t).cloned() { |
51 | return t; | |
1a4d82fc JJ |
52 | } |
53 | ||
e9174d1e | 54 | debug!("sizing_type_of {:?}", t); |
92a42be0 SL |
55 | let _recursion_lock = cx.enter_type_of(t); |
56 | ||
1a4d82fc | 57 | let llsizingty = match t.sty { |
c34b1796 | 58 | _ if !type_is_sized(cx.tcx(), t) => { |
54a0048b | 59 | Type::struct_(cx, &[Type::i8p(cx), unsized_info_ty(cx, t)], false) |
1a4d82fc JJ |
60 | } |
61 | ||
62682a34 SL |
62 | ty::TyBool => Type::bool(cx), |
63 | ty::TyChar => Type::char(cx), | |
64 | ty::TyInt(t) => Type::int_from_ty(cx, t), | |
65 | ty::TyUint(t) => Type::uint_from_ty(cx, t), | |
66 | ty::TyFloat(t) => Type::float_from_ty(cx, t), | |
5bcae85e | 67 | ty::TyNever => Type::nil(cx), |
1a4d82fc | 68 | |
c1a9b12d SL |
69 | ty::TyBox(ty) | |
70 | ty::TyRef(_, ty::TypeAndMut{ty, ..}) | | |
71 | ty::TyRawPtr(ty::TypeAndMut{ty, ..}) => { | |
1a4d82fc JJ |
72 | if type_is_sized(cx.tcx(), ty) { |
73 | Type::i8p(cx) | |
74 | } else { | |
54a0048b | 75 | Type::struct_(cx, &[Type::i8p(cx), unsized_info_ty(cx, ty)], false) |
1a4d82fc JJ |
76 | } |
77 | } | |
78 | ||
54a0048b SL |
79 | ty::TyFnDef(..) => Type::nil(cx), |
80 | ty::TyFnPtr(_) => Type::i8p(cx), | |
1a4d82fc | 81 | |
62682a34 | 82 | ty::TyArray(ty, size) => { |
1a4d82fc JJ |
83 | let llty = sizing_type_of(cx, ty); |
84 | let size = size as u64; | |
85 | ensure_array_fits_in_address_space(cx, llty, size, t); | |
86 | Type::array(&llty, size) | |
87 | } | |
88 | ||
62682a34 | 89 | ty::TyTuple(ref tys) if tys.is_empty() => { |
1a4d82fc JJ |
90 | Type::nil(cx) |
91 | } | |
92 | ||
62682a34 | 93 | ty::TyTuple(..) | ty::TyEnum(..) | ty::TyClosure(..) => { |
1a4d82fc | 94 | let repr = adt::represent_type(cx, t); |
7453a54e | 95 | adt::sizing_type_of(cx, &repr, false) |
1a4d82fc JJ |
96 | } |
97 | ||
62682a34 | 98 | ty::TyStruct(..) => { |
e9174d1e SL |
99 | if t.is_simd() { |
100 | let e = t.simd_type(cx.tcx()); | |
101 | if !e.is_machine() { | |
102 | cx.sess().fatal(&format!("monomorphising SIMD type `{}` with \ | |
103 | a non-machine element type `{}`", | |
104 | t, e)) | |
105 | } | |
106 | let llet = type_of(cx, e); | |
c1a9b12d | 107 | let n = t.simd_size(cx.tcx()) as u64; |
1a4d82fc JJ |
108 | ensure_array_fits_in_address_space(cx, llet, n, t); |
109 | Type::vector(&llet, n) | |
110 | } else { | |
111 | let repr = adt::represent_type(cx, t); | |
7453a54e | 112 | adt::sizing_type_of(cx, &repr, false) |
1a4d82fc JJ |
113 | } |
114 | } | |
115 | ||
5bcae85e SL |
116 | ty::TyProjection(..) | ty::TyInfer(..) | ty::TyParam(..) | |
117 | ty::TyAnon(..) | ty::TyError => { | |
54a0048b | 118 | bug!("fictitious type {:?} in sizing_type_of()", t) |
1a4d82fc | 119 | } |
54a0048b | 120 | ty::TySlice(_) | ty::TyTrait(..) | ty::TyStr => bug!() |
1a4d82fc JJ |
121 | }; |
122 | ||
54a0048b | 123 | debug!("--> mapped t={:?} to llsizingty={:?}", t, llsizingty); |
e9174d1e | 124 | |
1a4d82fc | 125 | cx.llsizingtypes().borrow_mut().insert(t, llsizingty); |
54a0048b SL |
126 | |
127 | // FIXME(eddyb) Temporary sanity check for ty::layout. | |
5bcae85e | 128 | let layout = cx.tcx().normalizing_infer_ctxt(Reveal::All).enter(|infcx| { |
a7813a04 XL |
129 | t.layout(&infcx) |
130 | }); | |
131 | match layout { | |
54a0048b SL |
132 | Ok(layout) => { |
133 | if !type_is_sized(cx.tcx(), t) { | |
134 | if !layout.is_unsized() { | |
135 | bug!("layout should be unsized for type `{}` / {:#?}", | |
136 | t, layout); | |
137 | } | |
138 | ||
139 | // Unsized types get turned into a fat pointer for LLVM. | |
140 | return llsizingty; | |
141 | } | |
142 | let r = layout.size(&cx.tcx().data_layout).bytes(); | |
143 | let l = machine::llsize_of_alloc(cx, llsizingty); | |
144 | if r != l { | |
145 | bug!("size differs (rustc: {}, llvm: {}) for type `{}` / {:#?}", | |
146 | r, l, t, layout); | |
147 | } | |
148 | let r = layout.align(&cx.tcx().data_layout).abi(); | |
149 | let l = machine::llalign_of_min(cx, llsizingty) as u64; | |
150 | if r != l { | |
151 | bug!("align differs (rustc: {}, llvm: {}) for type `{}` / {:#?}", | |
152 | r, l, t, layout); | |
153 | } | |
154 | } | |
155 | Err(e) => { | |
156 | bug!("failed to get layout for `{}`: {}", t, e); | |
157 | } | |
158 | } | |
1a4d82fc JJ |
159 | llsizingty |
160 | } | |
161 | ||
a7813a04 XL |
162 | pub fn fat_ptr_base_ty<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, ty: Ty<'tcx>) -> Type { |
163 | match ty.sty { | |
164 | ty::TyBox(t) | | |
165 | ty::TyRef(_, ty::TypeAndMut { ty: t, .. }) | | |
166 | ty::TyRawPtr(ty::TypeAndMut { ty: t, .. }) if !type_is_sized(ccx.tcx(), t) => { | |
167 | in_memory_type_of(ccx, t).ptr_to() | |
168 | } | |
169 | _ => bug!("expected fat ptr ty but got {:?}", ty) | |
170 | } | |
171 | } | |
172 | ||
54a0048b SL |
173 | fn unsized_info_ty<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, ty: Ty<'tcx>) -> Type { |
174 | let unsized_part = ccx.tcx().struct_tail(ty); | |
175 | match unsized_part.sty { | |
176 | ty::TyStr | ty::TyArray(..) | ty::TySlice(_) => { | |
177 | Type::uint_from_ty(ccx, ast::UintTy::Us) | |
178 | } | |
179 | ty::TyTrait(_) => Type::vtable_ptr(ccx), | |
180 | _ => bug!("Unexpected tail in unsized_info_ty: {:?} for ty={:?}", | |
181 | unsized_part, ty) | |
85aaf69f SL |
182 | } |
183 | } | |
184 | ||
54a0048b | 185 | pub fn immediate_type_of<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>, t: Ty<'tcx>) -> Type { |
c1a9b12d | 186 | if t.is_bool() { |
1a4d82fc JJ |
187 | Type::i1(cx) |
188 | } else { | |
189 | type_of(cx, t) | |
190 | } | |
191 | } | |
192 | ||
54a0048b | 193 | /// Get the LLVM type corresponding to a Rust type, i.e. `rustc::ty::Ty`. |
c34b1796 AL |
194 | /// This is the right LLVM type for an alloca containing a value of that type, |
195 | /// and the pointee of an Lvalue Datum (which is always a LLVM pointer). | |
196 | /// For unsized types, the returned type is a fat pointer, thus the resulting | |
197 | /// LLVM type for a `Trait` Lvalue is `{ i8*, void(i8*)** }*`, which is a double | |
198 | /// indirection to the actual data, unlike a `i8` Lvalue, which is just `i8*`. | |
199 | /// This is needed due to the treatment of immediate values, as a fat pointer | |
200 | /// is too large for it to be placed in SSA value (by our rules). | |
201 | /// For the raw type without far pointer indirection, see `in_memory_type_of`. | |
202 | pub fn type_of<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>, ty: Ty<'tcx>) -> Type { | |
203 | let ty = if !type_is_sized(cx.tcx(), ty) { | |
c1a9b12d | 204 | cx.tcx().mk_imm_ptr(ty) |
c34b1796 AL |
205 | } else { |
206 | ty | |
207 | }; | |
208 | in_memory_type_of(cx, ty) | |
209 | } | |
1a4d82fc | 210 | |
54a0048b | 211 | /// Get the LLVM type corresponding to a Rust type, i.e. `rustc::ty::Ty`. |
c34b1796 AL |
212 | /// This is the right LLVM type for a field/array element of that type, |
213 | /// and is the same as `type_of` for all Sized types. | |
214 | /// Unsized types, however, are represented by a "minimal unit", e.g. | |
215 | /// `[T]` becomes `T`, while `str` and `Trait` turn into `i8` - this | |
216 | /// is useful for indexing slices, as `&[T]`'s data pointer is `T*`. | |
217 | /// If the type is an unsized struct, the regular layout is generated, | |
218 | /// with the inner-most trailing unsized field using the "minimal unit" | |
219 | /// of that field's type - this is useful for taking the address of | |
220 | /// that field and ensuring the struct has the right alignment. | |
221 | /// For the LLVM type of a value as a whole, see `type_of`. | |
222 | /// NB: If you update this, be sure to update `sizing_type_of()` as well. | |
223 | pub fn in_memory_type_of<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>, t: Ty<'tcx>) -> Type { | |
1a4d82fc | 224 | // Check the cache. |
7453a54e SL |
225 | if let Some(&llty) = cx.lltypes().borrow().get(&t) { |
226 | return llty; | |
1a4d82fc JJ |
227 | } |
228 | ||
62682a34 | 229 | debug!("type_of {:?}", t); |
1a4d82fc | 230 | |
54a0048b | 231 | assert!(!t.has_escaping_regions(), "{:?} has escaping regions", t); |
1a4d82fc JJ |
232 | |
233 | // Replace any typedef'd types with their equivalent non-typedef | |
234 | // type. This ensures that all LLVM nominal types that contain | |
235 | // Rust types are defined as the same LLVM types. If we don't do | |
236 | // this then, e.g. `Option<{myfield: bool}>` would be a different | |
237 | // type than `Option<myrec>`. | |
e9174d1e | 238 | let t_norm = cx.tcx().erase_regions(&t); |
1a4d82fc JJ |
239 | |
240 | if t != t_norm { | |
c34b1796 | 241 | let llty = in_memory_type_of(cx, t_norm); |
54a0048b | 242 | debug!("--> normalized {:?} to {:?} llty={:?}", t, t_norm, llty); |
1a4d82fc JJ |
243 | cx.lltypes().borrow_mut().insert(t, llty); |
244 | return llty; | |
245 | } | |
246 | ||
247 | let mut llty = match t.sty { | |
62682a34 SL |
248 | ty::TyBool => Type::bool(cx), |
249 | ty::TyChar => Type::char(cx), | |
250 | ty::TyInt(t) => Type::int_from_ty(cx, t), | |
251 | ty::TyUint(t) => Type::uint_from_ty(cx, t), | |
252 | ty::TyFloat(t) => Type::float_from_ty(cx, t), | |
5bcae85e | 253 | ty::TyNever => Type::nil(cx), |
e9174d1e | 254 | ty::TyEnum(def, ref substs) => { |
1a4d82fc JJ |
255 | // Only create the named struct, but don't fill it in. We |
256 | // fill it in *after* placing it into the type cache. This | |
257 | // avoids creating more than one copy of the enum when one | |
258 | // of the enum's variants refers to the enum itself. | |
259 | let repr = adt::represent_type(cx, t); | |
260 | let tps = substs.types.get_slice(subst::TypeSpace); | |
e9174d1e | 261 | let name = llvm_type_name(cx, def.did, tps); |
7453a54e | 262 | adt::incomplete_type_of(cx, &repr, &name[..]) |
1a4d82fc | 263 | } |
62682a34 | 264 | ty::TyClosure(..) => { |
1a4d82fc JJ |
265 | // Only create the named struct, but don't fill it in. We |
266 | // fill it in *after* placing it into the type cache. | |
267 | let repr = adt::represent_type(cx, t); | |
268 | // Unboxed closures can have substitutions in all spaces | |
269 | // inherited from their environment, so we use entire | |
b039eaaf | 270 | // contents of the VecPerParamSpace to construct the llvm |
1a4d82fc | 271 | // name |
7453a54e | 272 | adt::incomplete_type_of(cx, &repr, "closure") |
1a4d82fc JJ |
273 | } |
274 | ||
c1a9b12d SL |
275 | ty::TyBox(ty) | |
276 | ty::TyRef(_, ty::TypeAndMut{ty, ..}) | | |
277 | ty::TyRawPtr(ty::TypeAndMut{ty, ..}) => { | |
c34b1796 | 278 | if !type_is_sized(cx.tcx(), ty) { |
62682a34 | 279 | if let ty::TyStr = ty.sty { |
1a4d82fc JJ |
280 | // This means we get a nicer name in the output (str is always |
281 | // unsized). | |
282 | cx.tn().find_type("str_slice").unwrap() | |
c34b1796 AL |
283 | } else { |
284 | let ptr_ty = in_memory_type_of(cx, ty).ptr_to(); | |
54a0048b | 285 | let info_ty = unsized_info_ty(cx, ty); |
c34b1796 | 286 | Type::struct_(cx, &[ptr_ty, info_ty], false) |
1a4d82fc | 287 | } |
c34b1796 AL |
288 | } else { |
289 | in_memory_type_of(cx, ty).ptr_to() | |
1a4d82fc JJ |
290 | } |
291 | } | |
292 | ||
62682a34 | 293 | ty::TyArray(ty, size) => { |
1a4d82fc | 294 | let size = size as u64; |
92a42be0 SL |
295 | // we must use `sizing_type_of` here as the type may |
296 | // not be fully initialized. | |
297 | let szty = sizing_type_of(cx, ty); | |
298 | ensure_array_fits_in_address_space(cx, szty, size, t); | |
299 | ||
c34b1796 | 300 | let llty = in_memory_type_of(cx, ty); |
1a4d82fc JJ |
301 | Type::array(&llty, size) |
302 | } | |
1a4d82fc | 303 | |
c34b1796 AL |
304 | // Unsized slice types (and str) have the type of their element, and |
305 | // traits have the type of u8. This is so that the data pointer inside | |
306 | // fat pointers is of the right type (e.g. for array accesses), even | |
307 | // when taking the address of an unsized field in a struct. | |
62682a34 SL |
308 | ty::TySlice(ty) => in_memory_type_of(cx, ty), |
309 | ty::TyStr | ty::TyTrait(..) => Type::i8(cx), | |
1a4d82fc | 310 | |
54a0048b SL |
311 | ty::TyFnDef(..) => Type::nil(cx), |
312 | ty::TyFnPtr(f) => { | |
313 | let sig = cx.tcx().erase_late_bound_regions(&f.sig); | |
a7813a04 | 314 | let sig = cx.tcx().normalize_associated_type(&sig); |
54a0048b | 315 | FnType::new(cx, f.abi, &sig, &[]).llvm_type(cx).ptr_to() |
1a4d82fc | 316 | } |
62682a34 SL |
317 | ty::TyTuple(ref tys) if tys.is_empty() => Type::nil(cx), |
318 | ty::TyTuple(..) => { | |
1a4d82fc | 319 | let repr = adt::represent_type(cx, t); |
7453a54e | 320 | adt::type_of(cx, &repr) |
1a4d82fc | 321 | } |
e9174d1e SL |
322 | ty::TyStruct(def, ref substs) => { |
323 | if t.is_simd() { | |
324 | let e = t.simd_type(cx.tcx()); | |
325 | if !e.is_machine() { | |
326 | cx.sess().fatal(&format!("monomorphising SIMD type `{}` with \ | |
327 | a non-machine element type `{}`", | |
328 | t, e)) | |
329 | } | |
330 | let llet = in_memory_type_of(cx, e); | |
c1a9b12d | 331 | let n = t.simd_size(cx.tcx()) as u64; |
1a4d82fc JJ |
332 | ensure_array_fits_in_address_space(cx, llet, n, t); |
333 | Type::vector(&llet, n) | |
334 | } else { | |
335 | // Only create the named struct, but don't fill it in. We fill it | |
336 | // in *after* placing it into the type cache. This prevents | |
337 | // infinite recursion with recursive struct types. | |
338 | let repr = adt::represent_type(cx, t); | |
339 | let tps = substs.types.get_slice(subst::TypeSpace); | |
e9174d1e | 340 | let name = llvm_type_name(cx, def.did, tps); |
7453a54e | 341 | adt::incomplete_type_of(cx, &repr, &name[..]) |
1a4d82fc JJ |
342 | } |
343 | } | |
344 | ||
5bcae85e SL |
345 | ty::TyInfer(..) | |
346 | ty::TyProjection(..) | | |
347 | ty::TyParam(..) | | |
348 | ty::TyAnon(..) | | |
349 | ty::TyError => bug!("type_of with {:?}", t), | |
1a4d82fc JJ |
350 | }; |
351 | ||
54a0048b | 352 | debug!("--> mapped t={:?} to llty={:?}", t, llty); |
1a4d82fc JJ |
353 | |
354 | cx.lltypes().borrow_mut().insert(t, llty); | |
355 | ||
356 | // If this was an enum or struct, fill in the type now. | |
357 | match t.sty { | |
62682a34 | 358 | ty::TyEnum(..) | ty::TyStruct(..) | ty::TyClosure(..) |
e9174d1e | 359 | if !t.is_simd() => { |
1a4d82fc | 360 | let repr = adt::represent_type(cx, t); |
7453a54e | 361 | adt::finish_type_of(cx, &repr, &mut llty); |
1a4d82fc JJ |
362 | } |
363 | _ => () | |
364 | } | |
365 | ||
c34b1796 | 366 | llty |
1a4d82fc JJ |
367 | } |
368 | ||
369 | pub fn align_of<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>, t: Ty<'tcx>) | |
370 | -> machine::llalign { | |
371 | let llty = sizing_type_of(cx, t); | |
372 | machine::llalign_of_min(cx, llty) | |
373 | } | |
374 | ||
c34b1796 | 375 | fn llvm_type_name<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>, |
e9174d1e | 376 | did: DefId, |
c34b1796 AL |
377 | tps: &[Ty<'tcx>]) |
378 | -> String { | |
c1a9b12d | 379 | let base = cx.tcx().item_path_str(did); |
62682a34 | 380 | let strings: Vec<String> = tps.iter().map(|t| t.to_string()).collect(); |
1a4d82fc JJ |
381 | let tstr = if strings.is_empty() { |
382 | base | |
383 | } else { | |
c1a9b12d | 384 | format!("{}<{}>", base, strings.join(", ")) |
1a4d82fc JJ |
385 | }; |
386 | ||
387 | if did.krate == 0 { | |
c34b1796 | 388 | tstr |
1a4d82fc | 389 | } else { |
c34b1796 | 390 | format!("{}.{}", did.krate, tstr) |
1a4d82fc JJ |
391 | } |
392 | } |