]>
Commit | Line | Data |
---|---|---|
1b1a35ee XL |
1 | use super::operand::{OperandRef, OperandValue}; |
2 | use super::place::PlaceRef; | |
3 | use super::FunctionCx; | |
4 | use crate::common::{span_invalid_monomorphization_error, IntPredicate}; | |
5 | use crate::glue; | |
6 | use crate::traits::*; | |
7 | use crate::MemFlags; | |
8 | ||
9 | use rustc_middle::ty::{self, Ty, TyCtxt}; | |
10 | use rustc_span::{sym, Span}; | |
11 | use rustc_target::abi::call::{FnAbi, PassMode}; | |
12 | ||
13 | fn copy_intrinsic<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( | |
14 | bx: &mut Bx, | |
15 | allow_overlap: bool, | |
16 | volatile: bool, | |
17 | ty: Ty<'tcx>, | |
18 | dst: Bx::Value, | |
19 | src: Bx::Value, | |
20 | count: Bx::Value, | |
21 | ) { | |
22 | let layout = bx.layout_of(ty); | |
23 | let size = layout.size; | |
24 | let align = layout.align.abi; | |
25 | let size = bx.mul(bx.const_usize(size.bytes()), count); | |
26 | let flags = if volatile { MemFlags::VOLATILE } else { MemFlags::empty() }; | |
27 | if allow_overlap { | |
28 | bx.memmove(dst, align, src, align, size, flags); | |
29 | } else { | |
30 | bx.memcpy(dst, align, src, align, size, flags); | |
31 | } | |
32 | } | |
33 | ||
34 | fn memset_intrinsic<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( | |
35 | bx: &mut Bx, | |
36 | volatile: bool, | |
37 | ty: Ty<'tcx>, | |
38 | dst: Bx::Value, | |
39 | val: Bx::Value, | |
40 | count: Bx::Value, | |
41 | ) { | |
42 | let layout = bx.layout_of(ty); | |
43 | let size = layout.size; | |
44 | let align = layout.align.abi; | |
45 | let size = bx.mul(bx.const_usize(size.bytes()), count); | |
46 | let flags = if volatile { MemFlags::VOLATILE } else { MemFlags::empty() }; | |
47 | bx.memset(dst, val, size, align, flags); | |
48 | } | |
49 | ||
50 | impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { | |
51 | pub fn codegen_intrinsic_call( | |
52 | bx: &mut Bx, | |
53 | instance: ty::Instance<'tcx>, | |
54 | fn_abi: &FnAbi<'tcx, Ty<'tcx>>, | |
55 | args: &[OperandRef<'tcx, Bx::Value>], | |
56 | llresult: Bx::Value, | |
57 | span: Span, | |
58 | ) { | |
59 | let callee_ty = instance.ty(bx.tcx(), ty::ParamEnv::reveal_all()); | |
60 | ||
61 | let (def_id, substs) = match *callee_ty.kind() { | |
62 | ty::FnDef(def_id, substs) => (def_id, substs), | |
63 | _ => bug!("expected fn item type, found {}", callee_ty), | |
64 | }; | |
65 | ||
66 | let sig = callee_ty.fn_sig(bx.tcx()); | |
fc512014 | 67 | let sig = bx.tcx().normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), sig); |
1b1a35ee XL |
68 | let arg_tys = sig.inputs(); |
69 | let ret_ty = sig.output(); | |
70 | let name = bx.tcx().item_name(def_id); | |
71 | let name_str = &*name.as_str(); | |
72 | ||
73 | let llret_ty = bx.backend_type(bx.layout_of(ret_ty)); | |
74 | let result = PlaceRef::new_sized(llresult, fn_abi.ret.layout); | |
75 | ||
76 | let llval = match name { | |
77 | sym::assume => { | |
78 | bx.assume(args[0].immediate()); | |
79 | return; | |
80 | } | |
81 | sym::abort => { | |
82 | bx.abort(); | |
83 | return; | |
84 | } | |
85 | ||
1b1a35ee XL |
86 | sym::va_start => bx.va_start(args[0].immediate()), |
87 | sym::va_end => bx.va_end(args[0].immediate()), | |
88 | sym::size_of_val => { | |
89 | let tp_ty = substs.type_at(0); | |
90 | if let OperandValue::Pair(_, meta) = args[0].val { | |
91 | let (llsize, _) = glue::size_and_align_of_dst(bx, tp_ty, Some(meta)); | |
92 | llsize | |
93 | } else { | |
94 | bx.const_usize(bx.layout_of(tp_ty).size.bytes()) | |
95 | } | |
96 | } | |
97 | sym::min_align_of_val => { | |
98 | let tp_ty = substs.type_at(0); | |
99 | if let OperandValue::Pair(_, meta) = args[0].val { | |
100 | let (_, llalign) = glue::size_and_align_of_dst(bx, tp_ty, Some(meta)); | |
101 | llalign | |
102 | } else { | |
103 | bx.const_usize(bx.layout_of(tp_ty).align.abi.bytes()) | |
104 | } | |
105 | } | |
fc512014 | 106 | sym::pref_align_of |
1b1a35ee XL |
107 | | sym::needs_drop |
108 | | sym::type_id | |
109 | | sym::type_name | |
110 | | sym::variant_count => { | |
111 | let value = bx | |
112 | .tcx() | |
113 | .const_eval_instance(ty::ParamEnv::reveal_all(), instance, None) | |
114 | .unwrap(); | |
115 | OperandRef::from_const(bx, value, ret_ty).immediate_or_packed_pair(bx) | |
116 | } | |
1b1a35ee | 117 | sym::offset => { |
94222f64 XL |
118 | let ty = substs.type_at(0); |
119 | let layout = bx.layout_of(ty); | |
1b1a35ee XL |
120 | let ptr = args[0].immediate(); |
121 | let offset = args[1].immediate(); | |
94222f64 | 122 | bx.inbounds_gep(bx.backend_type(layout), ptr, &[offset]) |
1b1a35ee XL |
123 | } |
124 | sym::arith_offset => { | |
94222f64 XL |
125 | let ty = substs.type_at(0); |
126 | let layout = bx.layout_of(ty); | |
1b1a35ee XL |
127 | let ptr = args[0].immediate(); |
128 | let offset = args[1].immediate(); | |
94222f64 | 129 | bx.gep(bx.backend_type(layout), ptr, &[offset]) |
1b1a35ee | 130 | } |
1b1a35ee XL |
131 | sym::copy => { |
132 | copy_intrinsic( | |
133 | bx, | |
134 | true, | |
135 | false, | |
136 | substs.type_at(0), | |
137 | args[1].immediate(), | |
138 | args[0].immediate(), | |
139 | args[2].immediate(), | |
140 | ); | |
141 | return; | |
142 | } | |
143 | sym::write_bytes => { | |
144 | memset_intrinsic( | |
145 | bx, | |
146 | false, | |
147 | substs.type_at(0), | |
148 | args[0].immediate(), | |
149 | args[1].immediate(), | |
150 | args[2].immediate(), | |
151 | ); | |
152 | return; | |
153 | } | |
154 | ||
155 | sym::volatile_copy_nonoverlapping_memory => { | |
156 | copy_intrinsic( | |
157 | bx, | |
158 | false, | |
159 | true, | |
160 | substs.type_at(0), | |
161 | args[0].immediate(), | |
162 | args[1].immediate(), | |
163 | args[2].immediate(), | |
164 | ); | |
165 | return; | |
166 | } | |
167 | sym::volatile_copy_memory => { | |
168 | copy_intrinsic( | |
169 | bx, | |
170 | true, | |
171 | true, | |
172 | substs.type_at(0), | |
173 | args[0].immediate(), | |
174 | args[1].immediate(), | |
175 | args[2].immediate(), | |
176 | ); | |
177 | return; | |
178 | } | |
179 | sym::volatile_set_memory => { | |
180 | memset_intrinsic( | |
181 | bx, | |
182 | true, | |
183 | substs.type_at(0), | |
184 | args[0].immediate(), | |
185 | args[1].immediate(), | |
186 | args[2].immediate(), | |
187 | ); | |
188 | return; | |
189 | } | |
190 | sym::volatile_store => { | |
191 | let dst = args[0].deref(bx.cx()); | |
192 | args[1].val.volatile_store(bx, dst); | |
193 | return; | |
194 | } | |
195 | sym::unaligned_volatile_store => { | |
196 | let dst = args[0].deref(bx.cx()); | |
197 | args[1].val.unaligned_volatile_store(bx, dst); | |
198 | return; | |
199 | } | |
200 | sym::add_with_overflow | |
201 | | sym::sub_with_overflow | |
202 | | sym::mul_with_overflow | |
1b1a35ee XL |
203 | | sym::unchecked_div |
204 | | sym::unchecked_rem | |
205 | | sym::unchecked_shl | |
206 | | sym::unchecked_shr | |
207 | | sym::unchecked_add | |
208 | | sym::unchecked_sub | |
209 | | sym::unchecked_mul | |
210 | | sym::exact_div => { | |
211 | let ty = arg_tys[0]; | |
212 | match int_type_width_signed(ty, bx.tcx()) { | |
213 | Some((_width, signed)) => match name { | |
214 | sym::add_with_overflow | |
215 | | sym::sub_with_overflow | |
216 | | sym::mul_with_overflow => { | |
217 | let op = match name { | |
218 | sym::add_with_overflow => OverflowOp::Add, | |
219 | sym::sub_with_overflow => OverflowOp::Sub, | |
220 | sym::mul_with_overflow => OverflowOp::Mul, | |
221 | _ => bug!(), | |
222 | }; | |
223 | let (val, overflow) = | |
224 | bx.checked_binop(op, ty, args[0].immediate(), args[1].immediate()); | |
225 | // Convert `i1` to a `bool`, and write it to the out parameter | |
226 | let val = bx.from_immediate(val); | |
227 | let overflow = bx.from_immediate(overflow); | |
228 | ||
229 | let dest = result.project_field(bx, 0); | |
230 | bx.store(val, dest.llval, dest.align); | |
231 | let dest = result.project_field(bx, 1); | |
232 | bx.store(overflow, dest.llval, dest.align); | |
233 | ||
234 | return; | |
235 | } | |
1b1a35ee XL |
236 | sym::exact_div => { |
237 | if signed { | |
238 | bx.exactsdiv(args[0].immediate(), args[1].immediate()) | |
239 | } else { | |
240 | bx.exactudiv(args[0].immediate(), args[1].immediate()) | |
241 | } | |
242 | } | |
243 | sym::unchecked_div => { | |
244 | if signed { | |
245 | bx.sdiv(args[0].immediate(), args[1].immediate()) | |
246 | } else { | |
247 | bx.udiv(args[0].immediate(), args[1].immediate()) | |
248 | } | |
249 | } | |
250 | sym::unchecked_rem => { | |
251 | if signed { | |
252 | bx.srem(args[0].immediate(), args[1].immediate()) | |
253 | } else { | |
254 | bx.urem(args[0].immediate(), args[1].immediate()) | |
255 | } | |
256 | } | |
257 | sym::unchecked_shl => bx.shl(args[0].immediate(), args[1].immediate()), | |
258 | sym::unchecked_shr => { | |
259 | if signed { | |
260 | bx.ashr(args[0].immediate(), args[1].immediate()) | |
261 | } else { | |
262 | bx.lshr(args[0].immediate(), args[1].immediate()) | |
263 | } | |
264 | } | |
265 | sym::unchecked_add => { | |
266 | if signed { | |
267 | bx.unchecked_sadd(args[0].immediate(), args[1].immediate()) | |
268 | } else { | |
269 | bx.unchecked_uadd(args[0].immediate(), args[1].immediate()) | |
270 | } | |
271 | } | |
272 | sym::unchecked_sub => { | |
273 | if signed { | |
274 | bx.unchecked_ssub(args[0].immediate(), args[1].immediate()) | |
275 | } else { | |
276 | bx.unchecked_usub(args[0].immediate(), args[1].immediate()) | |
277 | } | |
278 | } | |
279 | sym::unchecked_mul => { | |
280 | if signed { | |
281 | bx.unchecked_smul(args[0].immediate(), args[1].immediate()) | |
282 | } else { | |
283 | bx.unchecked_umul(args[0].immediate(), args[1].immediate()) | |
284 | } | |
285 | } | |
286 | _ => bug!(), | |
287 | }, | |
288 | None => { | |
289 | span_invalid_monomorphization_error( | |
290 | bx.tcx().sess, | |
291 | span, | |
292 | &format!( | |
293 | "invalid monomorphization of `{}` intrinsic: \ | |
294 | expected basic integer type, found `{}`", | |
295 | name, ty | |
296 | ), | |
297 | ); | |
298 | return; | |
299 | } | |
300 | } | |
301 | } | |
302 | sym::fadd_fast | sym::fsub_fast | sym::fmul_fast | sym::fdiv_fast | sym::frem_fast => { | |
303 | match float_type_width(arg_tys[0]) { | |
304 | Some(_width) => match name { | |
305 | sym::fadd_fast => bx.fadd_fast(args[0].immediate(), args[1].immediate()), | |
306 | sym::fsub_fast => bx.fsub_fast(args[0].immediate(), args[1].immediate()), | |
307 | sym::fmul_fast => bx.fmul_fast(args[0].immediate(), args[1].immediate()), | |
308 | sym::fdiv_fast => bx.fdiv_fast(args[0].immediate(), args[1].immediate()), | |
309 | sym::frem_fast => bx.frem_fast(args[0].immediate(), args[1].immediate()), | |
310 | _ => bug!(), | |
311 | }, | |
312 | None => { | |
313 | span_invalid_monomorphization_error( | |
314 | bx.tcx().sess, | |
315 | span, | |
316 | &format!( | |
317 | "invalid monomorphization of `{}` intrinsic: \ | |
318 | expected basic float type, found `{}`", | |
319 | name, arg_tys[0] | |
320 | ), | |
321 | ); | |
322 | return; | |
323 | } | |
324 | } | |
325 | } | |
326 | ||
327 | sym::float_to_int_unchecked => { | |
328 | if float_type_width(arg_tys[0]).is_none() { | |
329 | span_invalid_monomorphization_error( | |
330 | bx.tcx().sess, | |
331 | span, | |
332 | &format!( | |
333 | "invalid monomorphization of `float_to_int_unchecked` \ | |
334 | intrinsic: expected basic float type, \ | |
335 | found `{}`", | |
336 | arg_tys[0] | |
337 | ), | |
338 | ); | |
339 | return; | |
340 | } | |
341 | let (_width, signed) = match int_type_width_signed(ret_ty, bx.tcx()) { | |
342 | Some(pair) => pair, | |
343 | None => { | |
344 | span_invalid_monomorphization_error( | |
345 | bx.tcx().sess, | |
346 | span, | |
347 | &format!( | |
348 | "invalid monomorphization of `float_to_int_unchecked` \ | |
349 | intrinsic: expected basic integer type, \ | |
350 | found `{}`", | |
351 | ret_ty | |
352 | ), | |
353 | ); | |
354 | return; | |
355 | } | |
356 | }; | |
357 | if signed { | |
358 | bx.fptosi(args[0].immediate(), llret_ty) | |
359 | } else { | |
360 | bx.fptoui(args[0].immediate(), llret_ty) | |
361 | } | |
362 | } | |
363 | ||
364 | sym::discriminant_value => { | |
365 | if ret_ty.is_integral() { | |
366 | args[0].deref(bx.cx()).codegen_get_discr(bx, ret_ty) | |
367 | } else { | |
368 | span_bug!(span, "Invalid discriminant type for `{:?}`", arg_tys[0]) | |
369 | } | |
370 | } | |
371 | ||
372 | // This requires that atomic intrinsics follow a specific naming pattern: | |
373 | // "atomic_<operation>[_<ordering>]", and no ordering means SeqCst | |
374 | name if name_str.starts_with("atomic_") => { | |
375 | use crate::common::AtomicOrdering::*; | |
376 | use crate::common::{AtomicRmwBinOp, SynchronizationScope}; | |
377 | ||
378 | let split: Vec<&str> = name_str.split('_').collect(); | |
379 | ||
380 | let is_cxchg = split[1] == "cxchg" || split[1] == "cxchgweak"; | |
381 | let (order, failorder) = match split.len() { | |
382 | 2 => (SequentiallyConsistent, SequentiallyConsistent), | |
383 | 3 => match split[2] { | |
384 | "unordered" => (Unordered, Unordered), | |
385 | "relaxed" => (Monotonic, Monotonic), | |
386 | "acq" => (Acquire, Acquire), | |
387 | "rel" => (Release, Monotonic), | |
388 | "acqrel" => (AcquireRelease, Acquire), | |
389 | "failrelaxed" if is_cxchg => (SequentiallyConsistent, Monotonic), | |
390 | "failacq" if is_cxchg => (SequentiallyConsistent, Acquire), | |
391 | _ => bx.sess().fatal("unknown ordering in atomic intrinsic"), | |
392 | }, | |
393 | 4 => match (split[2], split[3]) { | |
394 | ("acq", "failrelaxed") if is_cxchg => (Acquire, Monotonic), | |
395 | ("acqrel", "failrelaxed") if is_cxchg => (AcquireRelease, Monotonic), | |
396 | _ => bx.sess().fatal("unknown ordering in atomic intrinsic"), | |
397 | }, | |
398 | _ => bx.sess().fatal("Atomic intrinsic not in correct format"), | |
399 | }; | |
400 | ||
401 | let invalid_monomorphization = |ty| { | |
402 | span_invalid_monomorphization_error( | |
403 | bx.tcx().sess, | |
404 | span, | |
405 | &format!( | |
406 | "invalid monomorphization of `{}` intrinsic: \ | |
407 | expected basic integer type, found `{}`", | |
408 | name, ty | |
409 | ), | |
410 | ); | |
411 | }; | |
412 | ||
413 | match split[1] { | |
414 | "cxchg" | "cxchgweak" => { | |
415 | let ty = substs.type_at(0); | |
fc512014 | 416 | if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_unsafe_ptr() { |
1b1a35ee | 417 | let weak = split[1] == "cxchgweak"; |
fc512014 XL |
418 | let mut dst = args[0].immediate(); |
419 | let mut cmp = args[1].immediate(); | |
420 | let mut src = args[2].immediate(); | |
421 | if ty.is_unsafe_ptr() { | |
422 | // Some platforms do not support atomic operations on pointers, | |
423 | // so we cast to integer first. | |
424 | let ptr_llty = bx.type_ptr_to(bx.type_isize()); | |
425 | dst = bx.pointercast(dst, ptr_llty); | |
426 | cmp = bx.ptrtoint(cmp, bx.type_isize()); | |
427 | src = bx.ptrtoint(src, bx.type_isize()); | |
428 | } | |
429 | let pair = bx.atomic_cmpxchg(dst, cmp, src, order, failorder, weak); | |
1b1a35ee XL |
430 | let val = bx.extract_value(pair, 0); |
431 | let success = bx.extract_value(pair, 1); | |
432 | let val = bx.from_immediate(val); | |
433 | let success = bx.from_immediate(success); | |
434 | ||
435 | let dest = result.project_field(bx, 0); | |
436 | bx.store(val, dest.llval, dest.align); | |
437 | let dest = result.project_field(bx, 1); | |
438 | bx.store(success, dest.llval, dest.align); | |
439 | return; | |
440 | } else { | |
441 | return invalid_monomorphization(ty); | |
442 | } | |
443 | } | |
444 | ||
445 | "load" => { | |
446 | let ty = substs.type_at(0); | |
fc512014 XL |
447 | if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_unsafe_ptr() { |
448 | let layout = bx.layout_of(ty); | |
449 | let size = layout.size; | |
450 | let mut source = args[0].immediate(); | |
451 | if ty.is_unsafe_ptr() { | |
452 | // Some platforms do not support atomic operations on pointers, | |
453 | // so we cast to integer first... | |
136023e0 XL |
454 | let llty = bx.type_isize(); |
455 | let ptr_llty = bx.type_ptr_to(llty); | |
fc512014 | 456 | source = bx.pointercast(source, ptr_llty); |
136023e0 | 457 | let result = bx.atomic_load(llty, source, order, size); |
fc512014 XL |
458 | // ... and then cast the result back to a pointer |
459 | bx.inttoptr(result, bx.backend_type(layout)) | |
460 | } else { | |
136023e0 | 461 | bx.atomic_load(bx.backend_type(layout), source, order, size) |
fc512014 | 462 | } |
1b1a35ee XL |
463 | } else { |
464 | return invalid_monomorphization(ty); | |
465 | } | |
466 | } | |
467 | ||
468 | "store" => { | |
469 | let ty = substs.type_at(0); | |
fc512014 | 470 | if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_unsafe_ptr() { |
1b1a35ee | 471 | let size = bx.layout_of(ty).size; |
fc512014 XL |
472 | let mut val = args[1].immediate(); |
473 | let mut ptr = args[0].immediate(); | |
474 | if ty.is_unsafe_ptr() { | |
475 | // Some platforms do not support atomic operations on pointers, | |
476 | // so we cast to integer first. | |
477 | let ptr_llty = bx.type_ptr_to(bx.type_isize()); | |
478 | ptr = bx.pointercast(ptr, ptr_llty); | |
479 | val = bx.ptrtoint(val, bx.type_isize()); | |
480 | } | |
481 | bx.atomic_store(val, ptr, order, size); | |
1b1a35ee XL |
482 | return; |
483 | } else { | |
484 | return invalid_monomorphization(ty); | |
485 | } | |
486 | } | |
487 | ||
488 | "fence" => { | |
489 | bx.atomic_fence(order, SynchronizationScope::CrossThread); | |
490 | return; | |
491 | } | |
492 | ||
493 | "singlethreadfence" => { | |
494 | bx.atomic_fence(order, SynchronizationScope::SingleThread); | |
495 | return; | |
496 | } | |
497 | ||
498 | // These are all AtomicRMW ops | |
499 | op => { | |
500 | let atom_op = match op { | |
501 | "xchg" => AtomicRmwBinOp::AtomicXchg, | |
502 | "xadd" => AtomicRmwBinOp::AtomicAdd, | |
503 | "xsub" => AtomicRmwBinOp::AtomicSub, | |
504 | "and" => AtomicRmwBinOp::AtomicAnd, | |
505 | "nand" => AtomicRmwBinOp::AtomicNand, | |
506 | "or" => AtomicRmwBinOp::AtomicOr, | |
507 | "xor" => AtomicRmwBinOp::AtomicXor, | |
508 | "max" => AtomicRmwBinOp::AtomicMax, | |
509 | "min" => AtomicRmwBinOp::AtomicMin, | |
510 | "umax" => AtomicRmwBinOp::AtomicUMax, | |
511 | "umin" => AtomicRmwBinOp::AtomicUMin, | |
512 | _ => bx.sess().fatal("unknown atomic operation"), | |
513 | }; | |
514 | ||
515 | let ty = substs.type_at(0); | |
fc512014 XL |
516 | if int_type_width_signed(ty, bx.tcx()).is_some() |
517 | || (ty.is_unsafe_ptr() && op == "xchg") | |
518 | { | |
519 | let mut ptr = args[0].immediate(); | |
520 | let mut val = args[1].immediate(); | |
521 | if ty.is_unsafe_ptr() { | |
522 | // Some platforms do not support atomic operations on pointers, | |
523 | // so we cast to integer first. | |
524 | let ptr_llty = bx.type_ptr_to(bx.type_isize()); | |
525 | ptr = bx.pointercast(ptr, ptr_llty); | |
526 | val = bx.ptrtoint(val, bx.type_isize()); | |
527 | } | |
528 | bx.atomic_rmw(atom_op, ptr, val, order) | |
1b1a35ee XL |
529 | } else { |
530 | return invalid_monomorphization(ty); | |
531 | } | |
532 | } | |
533 | } | |
534 | } | |
535 | ||
536 | sym::nontemporal_store => { | |
537 | let dst = args[0].deref(bx.cx()); | |
538 | args[1].val.nontemporal_store(bx, dst); | |
539 | return; | |
540 | } | |
541 | ||
542 | sym::ptr_guaranteed_eq | sym::ptr_guaranteed_ne => { | |
543 | let a = args[0].immediate(); | |
544 | let b = args[1].immediate(); | |
545 | if name == sym::ptr_guaranteed_eq { | |
546 | bx.icmp(IntPredicate::IntEQ, a, b) | |
547 | } else { | |
548 | bx.icmp(IntPredicate::IntNE, a, b) | |
549 | } | |
550 | } | |
551 | ||
552 | sym::ptr_offset_from => { | |
553 | let ty = substs.type_at(0); | |
554 | let pointee_size = bx.layout_of(ty).size; | |
555 | ||
556 | // This is the same sequence that Clang emits for pointer subtraction. | |
557 | // It can be neither `nsw` nor `nuw` because the input is treated as | |
558 | // unsigned but then the output is treated as signed, so neither works. | |
559 | let a = args[0].immediate(); | |
560 | let b = args[1].immediate(); | |
561 | let a = bx.ptrtoint(a, bx.type_isize()); | |
562 | let b = bx.ptrtoint(b, bx.type_isize()); | |
563 | let d = bx.sub(a, b); | |
564 | let pointee_size = bx.const_usize(pointee_size.bytes()); | |
565 | // this is where the signed magic happens (notice the `s` in `exactsdiv`) | |
566 | bx.exactsdiv(d, pointee_size) | |
567 | } | |
568 | ||
569 | _ => { | |
570 | // Need to use backend-specific things in the implementation. | |
571 | bx.codegen_intrinsic_call(instance, fn_abi, args, llresult, span); | |
572 | return; | |
573 | } | |
574 | }; | |
575 | ||
576 | if !fn_abi.ret.is_ignore() { | |
577 | if let PassMode::Cast(ty) = fn_abi.ret.mode { | |
578 | let ptr_llty = bx.type_ptr_to(bx.cast_backend_type(&ty)); | |
579 | let ptr = bx.pointercast(result.llval, ptr_llty); | |
580 | bx.store(llval, ptr, result.align); | |
581 | } else { | |
582 | OperandRef::from_immediate_or_packed_pair(bx, llval, result.layout) | |
583 | .val | |
584 | .store(bx, result); | |
585 | } | |
586 | } | |
587 | } | |
588 | } | |
589 | ||
590 | // Returns the width of an int Ty, and if it's signed or not | |
591 | // Returns None if the type is not an integer | |
592 | // FIXME: there’s multiple of this functions, investigate using some of the already existing | |
593 | // stuffs. | |
594 | fn int_type_width_signed(ty: Ty<'_>, tcx: TyCtxt<'_>) -> Option<(u64, bool)> { | |
595 | match ty.kind() { | |
29967ef6 XL |
596 | ty::Int(t) => { |
597 | Some((t.bit_width().unwrap_or(u64::from(tcx.sess.target.pointer_width)), true)) | |
598 | } | |
599 | ty::Uint(t) => { | |
600 | Some((t.bit_width().unwrap_or(u64::from(tcx.sess.target.pointer_width)), false)) | |
601 | } | |
1b1a35ee XL |
602 | _ => None, |
603 | } | |
604 | } | |
605 | ||
606 | // Returns the width of a float Ty | |
607 | // Returns None if the type is not a float | |
608 | fn float_type_width(ty: Ty<'_>) -> Option<u64> { | |
609 | match ty.kind() { | |
610 | ty::Float(t) => Some(t.bit_width()), | |
611 | _ => None, | |
612 | } | |
613 | } |