1 // Copyright 2012-2014 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.
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.
11 #![allow(non_upper_case_globals)]
13 use intrinsics::{self, Intrinsic};
17 use abi::{Abi, FnType};
19 use mir::lvalue::LvalueRef;
27 use rustc::ty::{self, Ty};
30 use syntax::symbol::Symbol;
33 use rustc::session::Session;
36 use std::cmp::Ordering;
39 use mir::lvalue::Alignment;
41 fn get_simple_intrinsic(ccx: &CrateContext, name: &str) -> Option<ValueRef> {
42 let llvm_name = match name {
43 "sqrtf32" => "llvm.sqrt.f32",
44 "sqrtf64" => "llvm.sqrt.f64",
45 "powif32" => "llvm.powi.f32",
46 "powif64" => "llvm.powi.f64",
47 "sinf32" => "llvm.sin.f32",
48 "sinf64" => "llvm.sin.f64",
49 "cosf32" => "llvm.cos.f32",
50 "cosf64" => "llvm.cos.f64",
51 "powf32" => "llvm.pow.f32",
52 "powf64" => "llvm.pow.f64",
53 "expf32" => "llvm.exp.f32",
54 "expf64" => "llvm.exp.f64",
55 "exp2f32" => "llvm.exp2.f32",
56 "exp2f64" => "llvm.exp2.f64",
57 "logf32" => "llvm.log.f32",
58 "logf64" => "llvm.log.f64",
59 "log10f32" => "llvm.log10.f32",
60 "log10f64" => "llvm.log10.f64",
61 "log2f32" => "llvm.log2.f32",
62 "log2f64" => "llvm.log2.f64",
63 "fmaf32" => "llvm.fma.f32",
64 "fmaf64" => "llvm.fma.f64",
65 "fabsf32" => "llvm.fabs.f32",
66 "fabsf64" => "llvm.fabs.f64",
67 "copysignf32" => "llvm.copysign.f32",
68 "copysignf64" => "llvm.copysign.f64",
69 "floorf32" => "llvm.floor.f32",
70 "floorf64" => "llvm.floor.f64",
71 "ceilf32" => "llvm.ceil.f32",
72 "ceilf64" => "llvm.ceil.f64",
73 "truncf32" => "llvm.trunc.f32",
74 "truncf64" => "llvm.trunc.f64",
75 "rintf32" => "llvm.rint.f32",
76 "rintf64" => "llvm.rint.f64",
77 "nearbyintf32" => "llvm.nearbyint.f32",
78 "nearbyintf64" => "llvm.nearbyint.f64",
79 "roundf32" => "llvm.round.f32",
80 "roundf64" => "llvm.round.f64",
81 "assume" => "llvm.assume",
82 "abort" => "llvm.trap",
85 Some(ccx.get_intrinsic(&llvm_name))
88 /// Remember to add all intrinsics here, in librustc_typeck/check/mod.rs,
89 /// and in libcore/intrinsics.rs; if you need access to any llvm intrinsics,
90 /// add them to librustc_trans/trans/context.rs
91 pub fn trans_intrinsic_call<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
100 let (def_id, substs, sig) = match callee_ty.sty {
101 ty::TyFnDef(def_id, substs, sig) => (def_id, substs, sig),
102 _ => bug!("expected fn item type, found {}", callee_ty)
105 let sig = tcx.erase_late_bound_regions_and_normalize(&sig);
106 let arg_tys = sig.inputs();
107 let ret_ty = sig.output();
108 let name = &*tcx.item_name(def_id).as_str();
110 let llret_ty = type_of::type_of(ccx, ret_ty);
112 let simple = get_simple_intrinsic(ccx, name);
113 let llval = match name {
114 _ if simple.is_some() => {
115 bcx.call(simple.unwrap(), &llargs, None)
121 let expect = ccx.get_intrinsic(&("llvm.expect.i1"));
122 bcx.call(expect, &[llargs[0], C_bool(ccx, true)], None)
125 let expect = ccx.get_intrinsic(&("llvm.expect.i1"));
126 bcx.call(expect, &[llargs[0], C_bool(ccx, false)], None)
129 try_intrinsic(bcx, ccx, llargs[0], llargs[1], llargs[2], llresult);
133 let llfn = ccx.get_intrinsic(&("llvm.debugtrap"));
134 bcx.call(llfn, &[], None)
137 let tp_ty = substs.type_at(0);
138 let lltp_ty = type_of::type_of(ccx, tp_ty);
139 C_uint(ccx, machine::llsize_of_alloc(ccx, lltp_ty))
142 let tp_ty = substs.type_at(0);
143 if !bcx.ccx.shared().type_is_sized(tp_ty) {
145 glue::size_and_align_of_dst(bcx, tp_ty, llargs[1]);
148 let lltp_ty = type_of::type_of(ccx, tp_ty);
149 C_uint(ccx, machine::llsize_of_alloc(ccx, lltp_ty))
153 let tp_ty = substs.type_at(0);
154 C_uint(ccx, ccx.align_of(tp_ty))
156 "min_align_of_val" => {
157 let tp_ty = substs.type_at(0);
158 if !bcx.ccx.shared().type_is_sized(tp_ty) {
160 glue::size_and_align_of_dst(bcx, tp_ty, llargs[1]);
163 C_uint(ccx, ccx.align_of(tp_ty))
167 let tp_ty = substs.type_at(0);
168 let lltp_ty = type_of::type_of(ccx, tp_ty);
169 C_uint(ccx, machine::llalign_of_pref(ccx, lltp_ty))
172 let tp_ty = substs.type_at(0);
173 let ty_name = Symbol::intern(&tp_ty.to_string()).as_str();
174 C_str_slice(ccx, ty_name)
177 C_u64(ccx, ccx.tcx().type_id_hash(substs.type_at(0)))
180 let ty = substs.type_at(0);
181 if !type_is_zero_size(ccx, ty) {
182 // Just zero out the stack slot.
183 // If we store a zero constant, LLVM will drown in vreg allocation for large data
184 // structures, and the generated code will be awful. (A telltale sign of this is
185 // large quantities of `mov [byte ptr foo],0` in the generated code.)
186 memset_intrinsic(bcx, false, ty, llresult, C_u8(ccx, 0), C_uint(ccx, 1usize));
190 // Effectively no-ops
195 let tp_ty = substs.type_at(0);
197 C_bool(ccx, bcx.ccx.shared().type_needs_drop(tp_ty))
201 let offset = llargs[1];
202 bcx.inbounds_gep(ptr, &[offset])
206 let offset = llargs[1];
207 bcx.gep(ptr, &[offset])
210 "copy_nonoverlapping" => {
211 copy_intrinsic(bcx, false, false, substs.type_at(0), llargs[1], llargs[0], llargs[2])
214 copy_intrinsic(bcx, true, false, substs.type_at(0), llargs[1], llargs[0], llargs[2])
217 memset_intrinsic(bcx, false, substs.type_at(0), llargs[0], llargs[1], llargs[2])
220 "volatile_copy_nonoverlapping_memory" => {
221 copy_intrinsic(bcx, false, true, substs.type_at(0), llargs[0], llargs[1], llargs[2])
223 "volatile_copy_memory" => {
224 copy_intrinsic(bcx, true, true, substs.type_at(0), llargs[0], llargs[1], llargs[2])
226 "volatile_set_memory" => {
227 memset_intrinsic(bcx, true, substs.type_at(0), llargs[0], llargs[1], llargs[2])
230 let tp_ty = substs.type_at(0);
231 let mut ptr = llargs[0];
232 if let Some(ty) = fn_ty.ret.cast {
233 ptr = bcx.pointercast(ptr, ty.ptr_to());
235 let load = bcx.volatile_load(ptr);
237 llvm::LLVMSetAlignment(load, ccx.align_of(tp_ty));
239 to_immediate(bcx, load, tp_ty)
241 "volatile_store" => {
242 let tp_ty = substs.type_at(0);
243 if type_is_fat_ptr(bcx.ccx, tp_ty) {
244 bcx.volatile_store(llargs[1], get_dataptr(bcx, llargs[0]));
245 bcx.volatile_store(llargs[2], get_meta(bcx, llargs[0]));
247 let val = if fn_ty.args[1].is_indirect() {
248 bcx.load(llargs[1], None)
250 from_immediate(bcx, llargs[1])
252 let ptr = bcx.pointercast(llargs[0], val_ty(val).ptr_to());
253 let store = bcx.volatile_store(val, ptr);
255 llvm::LLVMSetAlignment(store, ccx.align_of(tp_ty));
261 "ctlz" | "cttz" | "ctpop" | "bswap" |
262 "add_with_overflow" | "sub_with_overflow" | "mul_with_overflow" |
263 "overflowing_add" | "overflowing_sub" | "overflowing_mul" |
264 "unchecked_div" | "unchecked_rem" | "unchecked_shl" | "unchecked_shr" => {
265 let sty = &arg_tys[0].sty;
266 match int_type_width_signed(sty, ccx) {
267 Some((width, signed)) =>
270 let y = C_bool(bcx.ccx, false);
271 let llfn = ccx.get_intrinsic(&format!("llvm.{}.i{}", name, width));
272 bcx.call(llfn, &[llargs[0], y], None)
274 "ctpop" => bcx.call(ccx.get_intrinsic(&format!("llvm.ctpop.i{}", width)),
278 llargs[0] // byte swap a u8/i8 is just a no-op
280 bcx.call(ccx.get_intrinsic(&format!("llvm.bswap.i{}", width)),
284 "add_with_overflow" | "sub_with_overflow" | "mul_with_overflow" => {
285 let intrinsic = format!("llvm.{}{}.with.overflow.i{}",
286 if signed { 's' } else { 'u' },
288 let llfn = bcx.ccx.get_intrinsic(&intrinsic);
290 // Convert `i1` to a `bool`, and write it to the out parameter
291 let val = bcx.call(llfn, &[llargs[0], llargs[1]], None);
292 let result = bcx.extract_value(val, 0);
293 let overflow = bcx.zext(bcx.extract_value(val, 1), Type::bool(ccx));
294 bcx.store(result, bcx.struct_gep(llresult, 0), None);
295 bcx.store(overflow, bcx.struct_gep(llresult, 1), None);
299 "overflowing_add" => bcx.add(llargs[0], llargs[1]),
300 "overflowing_sub" => bcx.sub(llargs[0], llargs[1]),
301 "overflowing_mul" => bcx.mul(llargs[0], llargs[1]),
304 bcx.sdiv(llargs[0], llargs[1])
306 bcx.udiv(llargs[0], llargs[1])
310 bcx.srem(llargs[0], llargs[1])
312 bcx.urem(llargs[0], llargs[1])
314 "unchecked_shl" => bcx.shl(llargs[0], llargs[1]),
317 bcx.ashr(llargs[0], llargs[1])
319 bcx.lshr(llargs[0], llargs[1])
324 span_invalid_monomorphization_error(
326 &format!("invalid monomorphization of `{}` intrinsic: \
327 expected basic integer type, found `{}`", name, sty));
333 "fadd_fast" | "fsub_fast" | "fmul_fast" | "fdiv_fast" | "frem_fast" => {
334 let sty = &arg_tys[0].sty;
335 match float_type_width(sty) {
338 "fadd_fast" => bcx.fadd_fast(llargs[0], llargs[1]),
339 "fsub_fast" => bcx.fsub_fast(llargs[0], llargs[1]),
340 "fmul_fast" => bcx.fmul_fast(llargs[0], llargs[1]),
341 "fdiv_fast" => bcx.fdiv_fast(llargs[0], llargs[1]),
342 "frem_fast" => bcx.frem_fast(llargs[0], llargs[1]),
346 span_invalid_monomorphization_error(
348 &format!("invalid monomorphization of `{}` intrinsic: \
349 expected basic float type, found `{}`", name, sty));
356 "discriminant_value" => {
357 let val_ty = substs.type_at(0);
359 ty::TyAdt(adt, ..) if adt.is_enum() => {
360 adt::trans_get_discr(bcx, val_ty, llargs[0], Alignment::AbiAligned,
361 Some(llret_ty), true)
363 _ => C_null(llret_ty)
366 name if name.starts_with("simd_") => {
367 generic_simd_intrinsic(bcx, name,
373 // This requires that atomic intrinsics follow a specific naming pattern:
374 // "atomic_<operation>[_<ordering>]", and no ordering means SeqCst
375 name if name.starts_with("atomic_") => {
376 use llvm::AtomicOrdering::*;
378 let split: Vec<&str> = name.split('_').collect();
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 =>
390 (SequentiallyConsistent, Monotonic),
391 "failacq" if is_cxchg =>
392 (SequentiallyConsistent, Acquire),
393 _ => ccx.sess().fatal("unknown ordering in atomic intrinsic")
395 4 => match (split[2], split[3]) {
396 ("acq", "failrelaxed") if is_cxchg =>
397 (Acquire, Monotonic),
398 ("acqrel", "failrelaxed") if is_cxchg =>
399 (AcquireRelease, Monotonic),
400 _ => ccx.sess().fatal("unknown ordering in atomic intrinsic")
402 _ => ccx.sess().fatal("Atomic intrinsic not in correct format"),
405 let invalid_monomorphization = |sty| {
406 span_invalid_monomorphization_error(tcx.sess, span,
407 &format!("invalid monomorphization of `{}` intrinsic: \
408 expected basic integer type, found `{}`", name, sty));
412 "cxchg" | "cxchgweak" => {
413 let sty = &substs.type_at(0).sty;
414 if int_type_width_signed(sty, ccx).is_some() {
415 let weak = if split[1] == "cxchgweak" { llvm::True } else { llvm::False };
416 let val = bcx.atomic_cmpxchg(llargs[0], llargs[1], llargs[2], order,
418 let result = bcx.extract_value(val, 0);
419 let success = bcx.zext(bcx.extract_value(val, 1), Type::bool(bcx.ccx));
420 bcx.store(result, bcx.struct_gep(llresult, 0), None);
421 bcx.store(success, bcx.struct_gep(llresult, 1), None);
423 invalid_monomorphization(sty);
429 let sty = &substs.type_at(0).sty;
430 if int_type_width_signed(sty, ccx).is_some() {
431 bcx.atomic_load(llargs[0], order)
433 invalid_monomorphization(sty);
439 let sty = &substs.type_at(0).sty;
440 if int_type_width_signed(sty, ccx).is_some() {
441 bcx.atomic_store(llargs[1], llargs[0], order);
443 invalid_monomorphization(sty);
449 bcx.atomic_fence(order, llvm::SynchronizationScope::CrossThread);
453 "singlethreadfence" => {
454 bcx.atomic_fence(order, llvm::SynchronizationScope::SingleThread);
458 // These are all AtomicRMW ops
460 let atom_op = match op {
461 "xchg" => llvm::AtomicXchg,
462 "xadd" => llvm::AtomicAdd,
463 "xsub" => llvm::AtomicSub,
464 "and" => llvm::AtomicAnd,
465 "nand" => llvm::AtomicNand,
466 "or" => llvm::AtomicOr,
467 "xor" => llvm::AtomicXor,
468 "max" => llvm::AtomicMax,
469 "min" => llvm::AtomicMin,
470 "umax" => llvm::AtomicUMax,
471 "umin" => llvm::AtomicUMin,
472 _ => ccx.sess().fatal("unknown atomic operation")
475 let sty = &substs.type_at(0).sty;
476 if int_type_width_signed(sty, ccx).is_some() {
477 bcx.atomic_rmw(atom_op, llargs[0], llargs[1], order)
479 invalid_monomorphization(sty);
487 let intr = match Intrinsic::find(&name) {
489 None => bug!("unknown intrinsic '{}'", name),
491 fn one<T>(x: Vec<T>) -> T {
492 assert_eq!(x.len(), 1);
493 x.into_iter().next().unwrap()
495 fn ty_to_type(ccx: &CrateContext, t: &intrinsics::Type,
496 any_changes_needed: &mut bool) -> Vec<Type> {
497 use intrinsics::Type::*;
499 Void => vec![Type::void(ccx)],
500 Integer(_signed, width, llvm_width) => {
501 *any_changes_needed |= width != llvm_width;
502 vec![Type::ix(ccx, llvm_width as u64)]
506 32 => vec![Type::f32(ccx)],
507 64 => vec![Type::f64(ccx)],
511 Pointer(ref t, ref llvm_elem, _const) => {
512 *any_changes_needed |= llvm_elem.is_some();
514 let t = llvm_elem.as_ref().unwrap_or(t);
515 let elem = one(ty_to_type(ccx, t, any_changes_needed));
518 Vector(ref t, ref llvm_elem, length) => {
519 *any_changes_needed |= llvm_elem.is_some();
521 let t = llvm_elem.as_ref().unwrap_or(t);
522 let elem = one(ty_to_type(ccx, t, any_changes_needed));
523 vec![Type::vector(&elem, length as u64)]
525 Aggregate(false, ref contents) => {
526 let elems = contents.iter()
527 .map(|t| one(ty_to_type(ccx, t, any_changes_needed)))
528 .collect::<Vec<_>>();
529 vec![Type::struct_(ccx, &elems, false)]
531 Aggregate(true, ref contents) => {
532 *any_changes_needed = true;
534 .flat_map(|t| ty_to_type(ccx, t, any_changes_needed))
540 // This allows an argument list like `foo, (bar, baz),
541 // qux` to be converted into `foo, bar, baz, qux`, integer
542 // arguments to be truncated as needed and pointers to be
544 fn modify_as_needed<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
545 t: &intrinsics::Type,
551 intrinsics::Type::Aggregate(true, ref contents) => {
552 // We found a tuple that needs squishing! So
553 // run over the tuple and load each field.
555 // This assumes the type is "simple", i.e. no
556 // destructors, and the contents are SIMD
558 assert!(!bcx.ccx.shared().type_needs_drop(arg_type));
559 let arg = LvalueRef::new_sized_ty(llarg, arg_type, Alignment::AbiAligned);
560 (0..contents.len()).map(|i| {
561 let (ptr, align) = arg.trans_field_ptr(bcx, i);
562 bcx.load(ptr, align.to_align())
565 intrinsics::Type::Pointer(_, Some(ref llvm_elem), _) => {
566 let llvm_elem = one(ty_to_type(bcx.ccx, llvm_elem, &mut false));
567 vec![bcx.pointercast(llarg, llvm_elem.ptr_to())]
569 intrinsics::Type::Vector(_, Some(ref llvm_elem), length) => {
570 let llvm_elem = one(ty_to_type(bcx.ccx, llvm_elem, &mut false));
571 vec![bcx.bitcast(llarg, Type::vector(&llvm_elem, length as u64))]
573 intrinsics::Type::Integer(_, width, llvm_width) if width != llvm_width => {
574 // the LLVM intrinsic uses a smaller integer
575 // size than the C intrinsic's signature, so
576 // we have to trim it down here.
577 vec![bcx.trunc(llarg, Type::ix(bcx.ccx, llvm_width as u64))]
584 let mut any_changes_needed = false;
585 let inputs = intr.inputs.iter()
586 .flat_map(|t| ty_to_type(ccx, t, &mut any_changes_needed))
587 .collect::<Vec<_>>();
589 let mut out_changes = false;
590 let outputs = one(ty_to_type(ccx, &intr.output, &mut out_changes));
591 // outputting a flattened aggregate is nonsense
592 assert!(!out_changes);
594 let llargs = if !any_changes_needed {
595 // no aggregates to flatten, so no change needed
598 // there are some aggregates that need to be flattened
599 // in the LLVM call, so we need to run over the types
600 // again to find them and extract the arguments
604 .flat_map(|((t, llarg), ty)| modify_as_needed(bcx, t, ty, *llarg))
607 assert_eq!(inputs.len(), llargs.len());
609 let val = match intr.definition {
610 intrinsics::IntrinsicDef::Named(name) => {
611 let f = declare::declare_cfn(ccx,
613 Type::func(&inputs, &outputs));
614 bcx.call(f, &llargs, None)
619 intrinsics::Type::Aggregate(flatten, ref elems) => {
620 // the output is a tuple so we need to munge it properly
623 for i in 0..elems.len() {
624 let val = bcx.extract_value(val, i);
625 bcx.store(val, bcx.struct_gep(llresult, i), None);
634 if val_ty(llval) != Type::void(ccx) && machine::llsize_of_alloc(ccx, val_ty(llval)) != 0 {
635 if let Some(ty) = fn_ty.ret.cast {
636 let ptr = bcx.pointercast(llresult, ty.ptr_to());
637 bcx.store(llval, ptr, Some(ccx.align_of(ret_ty)));
639 store_ty(bcx, llval, llresult, Alignment::AbiAligned, ret_ty);
644 fn copy_intrinsic<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
653 let lltp_ty = type_of::type_of(ccx, tp_ty);
654 let align = C_i32(ccx, ccx.align_of(tp_ty) as i32);
655 let size = machine::llsize_of(ccx, lltp_ty);
656 let int_size = machine::llbitsize_of_real(ccx, ccx.int_type());
658 let operation = if allow_overlap {
664 let name = format!("llvm.{}.p0i8.p0i8.i{}", operation, int_size);
666 let dst_ptr = bcx.pointercast(dst, Type::i8p(ccx));
667 let src_ptr = bcx.pointercast(src, Type::i8p(ccx));
668 let llfn = ccx.get_intrinsic(&name);
673 bcx.mul(size, count),
675 C_bool(ccx, volatile)],
679 fn memset_intrinsic<'a, 'tcx>(
680 bcx: &Builder<'a, 'tcx>,
688 let align = C_i32(ccx, ccx.align_of(ty) as i32);
689 let lltp_ty = type_of::type_of(ccx, ty);
690 let size = machine::llsize_of(ccx, lltp_ty);
691 let dst = bcx.pointercast(dst, Type::i8p(ccx));
692 call_memset(bcx, dst, val, bcx.mul(size, count), align, volatile)
695 fn try_intrinsic<'a, 'tcx>(
696 bcx: &Builder<'a, 'tcx>,
703 if bcx.sess().no_landing_pads() {
704 bcx.call(func, &[data], None);
705 bcx.store(C_null(Type::i8p(&bcx.ccx)), dest, None);
706 } else if wants_msvc_seh(bcx.sess()) {
707 trans_msvc_try(bcx, ccx, func, data, local_ptr, dest);
709 trans_gnu_try(bcx, ccx, func, data, local_ptr, dest);
713 // MSVC's definition of the `rust_try` function.
715 // This implementation uses the new exception handling instructions in LLVM
716 // which have support in LLVM for SEH on MSVC targets. Although these
717 // instructions are meant to work for all targets, as of the time of this
718 // writing, however, LLVM does not recommend the usage of these new instructions
719 // as the old ones are still more optimized.
720 fn trans_msvc_try<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
726 let llfn = get_rust_try_fn(ccx, &mut |bcx| {
729 bcx.set_personality_fn(bcx.ccx.eh_personality());
731 let normal = bcx.build_sibling_block("normal");
732 let catchswitch = bcx.build_sibling_block("catchswitch");
733 let catchpad = bcx.build_sibling_block("catchpad");
734 let caught = bcx.build_sibling_block("caught");
736 let func = llvm::get_param(bcx.llfn(), 0);
737 let data = llvm::get_param(bcx.llfn(), 1);
738 let local_ptr = llvm::get_param(bcx.llfn(), 2);
740 // We're generating an IR snippet that looks like:
742 // declare i32 @rust_try(%func, %data, %ptr) {
743 // %slot = alloca i64*
744 // invoke %func(%data) to label %normal unwind label %catchswitch
750 // %cs = catchswitch within none [%catchpad] unwind to caller
753 // %tok = catchpad within %cs [%type_descriptor, 0, %slot]
754 // %ptr[0] = %slot[0]
755 // %ptr[1] = %slot[1]
756 // catchret from %tok to label %caught
762 // This structure follows the basic usage of throw/try/catch in LLVM.
763 // For example, compile this C++ snippet to see what LLVM generates:
765 // #include <stdint.h>
767 // int bar(void (*foo)(void), uint64_t *ret) {
771 // } catch(uint64_t a[2]) {
778 // More information can be found in libstd's seh.rs implementation.
779 let i64p = Type::i64(ccx).ptr_to();
780 let slot = bcx.alloca(i64p, "slot");
781 bcx.invoke(func, &[data], normal.llbb(), catchswitch.llbb(),
784 normal.ret(C_i32(ccx, 0));
786 let cs = catchswitch.catch_switch(None, None, 1);
787 catchswitch.add_handler(cs, catchpad.llbb());
790 let tydesc = match tcx.lang_items.msvc_try_filter() {
791 Some(did) => ::consts::get_static(ccx, did),
792 None => bug!("msvc_try_filter not defined"),
794 let tok = catchpad.catch_pad(cs, &[tydesc, C_i32(ccx, 0), slot]);
795 let addr = catchpad.load(slot, None);
796 let arg1 = catchpad.load(addr, None);
797 let val1 = C_i32(ccx, 1);
798 let arg2 = catchpad.load(catchpad.inbounds_gep(addr, &[val1]), None);
799 let local_ptr = catchpad.bitcast(local_ptr, i64p);
800 catchpad.store(arg1, local_ptr, None);
801 catchpad.store(arg2, catchpad.inbounds_gep(local_ptr, &[val1]), None);
802 catchpad.catch_ret(tok, caught.llbb());
804 caught.ret(C_i32(ccx, 1));
807 // Note that no invoke is used here because by definition this function
808 // can't panic (that's what it's catching).
809 let ret = bcx.call(llfn, &[func, data, local_ptr], None);
810 bcx.store(ret, dest, None);
813 // Definition of the standard "try" function for Rust using the GNU-like model
814 // of exceptions (e.g. the normal semantics of LLVM's landingpad and invoke
817 // This translation is a little surprising because we always call a shim
818 // function instead of inlining the call to `invoke` manually here. This is done
819 // because in LLVM we're only allowed to have one personality per function
820 // definition. The call to the `try` intrinsic is being inlined into the
821 // function calling it, and that function may already have other personality
822 // functions in play. By calling a shim we're guaranteed that our shim will have
823 // the right personality function.
824 fn trans_gnu_try<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
830 let llfn = get_rust_try_fn(ccx, &mut |bcx| {
833 // Translates the shims described above:
836 // invoke %func(%args...) normal %normal unwind %catch
842 // (ptr, _) = landingpad
843 // store ptr, %local_ptr
846 // Note that the `local_ptr` data passed into the `try` intrinsic is
847 // expected to be `*mut *mut u8` for this to actually work, but that's
848 // managed by the standard library.
850 let then = bcx.build_sibling_block("then");
851 let catch = bcx.build_sibling_block("catch");
853 let func = llvm::get_param(bcx.llfn(), 0);
854 let data = llvm::get_param(bcx.llfn(), 1);
855 let local_ptr = llvm::get_param(bcx.llfn(), 2);
856 bcx.invoke(func, &[data], then.llbb(), catch.llbb(), None);
857 then.ret(C_i32(ccx, 0));
859 // Type indicator for the exception being thrown.
861 // The first value in this tuple is a pointer to the exception object
862 // being thrown. The second value is a "selector" indicating which of
863 // the landing pad clauses the exception's type had been matched to.
864 // rust_try ignores the selector.
865 let lpad_ty = Type::struct_(ccx, &[Type::i8p(ccx), Type::i32(ccx)],
867 let vals = catch.landing_pad(lpad_ty, bcx.ccx.eh_personality(), 1, catch.llfn());
868 catch.add_clause(vals, C_null(Type::i8p(ccx)));
869 let ptr = catch.extract_value(vals, 0);
870 catch.store(ptr, catch.bitcast(local_ptr, Type::i8p(ccx).ptr_to()), None);
871 catch.ret(C_i32(ccx, 1));
874 // Note that no invoke is used here because by definition this function
875 // can't panic (that's what it's catching).
876 let ret = bcx.call(llfn, &[func, data, local_ptr], None);
877 bcx.store(ret, dest, None);
880 // Helper function to give a Block to a closure to translate a shim function.
881 // This is currently primarily used for the `try` intrinsic functions above.
882 fn gen_fn<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
884 inputs: Vec<Ty<'tcx>>,
886 trans: &mut for<'b> FnMut(Builder<'b, 'tcx>))
888 let rust_fn_ty = ccx.tcx().mk_fn_ptr(ty::Binder(ccx.tcx().mk_fn_sig(
892 hir::Unsafety::Unsafe,
895 let llfn = declare::define_internal_fn(ccx, name, rust_fn_ty);
896 let bcx = Builder::new_block(ccx, llfn, "entry-block");
901 // Helper function used to get a handle to the `__rust_try` function used to
904 // This function is only generated once and is then cached.
905 fn get_rust_try_fn<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
906 trans: &mut for<'b> FnMut(Builder<'b, 'tcx>))
908 if let Some(llfn) = ccx.rust_try_fn().get() {
912 // Define the type up front for the signature of the rust_try function.
914 let i8p = tcx.mk_mut_ptr(tcx.types.i8);
915 let fn_ty = tcx.mk_fn_ptr(ty::Binder(tcx.mk_fn_sig(
919 hir::Unsafety::Unsafe,
922 let output = tcx.types.i32;
923 let rust_try = gen_fn(ccx, "__rust_try", vec![fn_ty, i8p, i8p], output, trans);
924 ccx.rust_try_fn().set(Some(rust_try));
928 fn span_invalid_monomorphization_error(a: &Session, b: Span, c: &str) {
929 span_err!(a, b, E0511, "{}", c);
932 fn generic_simd_intrinsic<'a, 'tcx>(
933 bcx: &Builder<'a, 'tcx>,
941 // macros for error handling:
942 macro_rules! emit_error {
946 ($msg: tt, $($fmt: tt)*) => {
947 span_invalid_monomorphization_error(
949 &format!(concat!("invalid monomorphization of `{}` intrinsic: ",
954 macro_rules! require {
955 ($cond: expr, $($fmt: tt)*) => {
957 emit_error!($($fmt)*);
958 return C_nil(bcx.ccx)
962 macro_rules! require_simd {
963 ($ty: expr, $position: expr) => {
964 require!($ty.is_simd(), "expected SIMD {} type, found non-SIMD `{}`", $position, $ty)
971 let sig = tcx.erase_late_bound_regions_and_normalize(&callee_ty.fn_sig());
972 let arg_tys = sig.inputs();
974 // every intrinsic takes a SIMD vector as its first argument
975 require_simd!(arg_tys[0], "input");
976 let in_ty = arg_tys[0];
977 let in_elem = arg_tys[0].simd_type(tcx);
978 let in_len = arg_tys[0].simd_size(tcx);
980 let comparison = match name {
981 "simd_eq" => Some(hir::BiEq),
982 "simd_ne" => Some(hir::BiNe),
983 "simd_lt" => Some(hir::BiLt),
984 "simd_le" => Some(hir::BiLe),
985 "simd_gt" => Some(hir::BiGt),
986 "simd_ge" => Some(hir::BiGe),
990 if let Some(cmp_op) = comparison {
991 require_simd!(ret_ty, "return");
993 let out_len = ret_ty.simd_size(tcx);
994 require!(in_len == out_len,
995 "expected return type with length {} (same as input type `{}`), \
996 found `{}` with length {}",
999 require!(llret_ty.element_type().kind() == llvm::Integer,
1000 "expected return type with integer elements, found `{}` with non-integer `{}`",
1002 ret_ty.simd_type(tcx));
1004 return compare_simd_types(bcx,
1012 if name.starts_with("simd_shuffle") {
1013 let n: usize = match name["simd_shuffle".len()..].parse() {
1015 Err(_) => span_bug!(span,
1016 "bad `simd_shuffle` instruction only caught in trans?")
1019 require_simd!(ret_ty, "return");
1021 let out_len = ret_ty.simd_size(tcx);
1022 require!(out_len == n,
1023 "expected return type of length {}, found `{}` with length {}",
1024 n, ret_ty, out_len);
1025 require!(in_elem == ret_ty.simd_type(tcx),
1026 "expected return element type `{}` (element of input `{}`), \
1027 found `{}` with element type `{}`",
1029 ret_ty, ret_ty.simd_type(tcx));
1031 let total_len = in_len as u128 * 2;
1033 let vector = llargs[2];
1035 let indices: Option<Vec<_>> = (0..n)
1038 let val = const_get_elt(vector, &[i as libc::c_uint]);
1039 match const_to_opt_u128(val, true) {
1041 emit_error!("shuffle index #{} is not a constant", arg_idx);
1044 Some(idx) if idx >= total_len => {
1045 emit_error!("shuffle index #{} is out of bounds (limit {})",
1046 arg_idx, total_len);
1049 Some(idx) => Some(C_i32(bcx.ccx, idx as i32)),
1053 let indices = match indices {
1055 None => return C_null(llret_ty)
1058 return bcx.shuffle_vector(llargs[0], llargs[1], C_vector(&indices))
1061 if name == "simd_insert" {
1062 require!(in_elem == arg_tys[2],
1063 "expected inserted type `{}` (element of input `{}`), found `{}`",
1064 in_elem, in_ty, arg_tys[2]);
1065 return bcx.insert_element(llargs[0], llargs[2], llargs[1])
1067 if name == "simd_extract" {
1068 require!(ret_ty == in_elem,
1069 "expected return type `{}` (element of input `{}`), found `{}`",
1070 in_elem, in_ty, ret_ty);
1071 return bcx.extract_element(llargs[0], llargs[1])
1074 if name == "simd_cast" {
1075 require_simd!(ret_ty, "return");
1076 let out_len = ret_ty.simd_size(tcx);
1077 require!(in_len == out_len,
1078 "expected return type with length {} (same as input type `{}`), \
1079 found `{}` with length {}",
1082 // casting cares about nominal type, not just structural type
1083 let out_elem = ret_ty.simd_type(tcx);
1085 if in_elem == out_elem { return llargs[0]; }
1087 enum Style { Float, Int(/* is signed? */ bool), Unsupported }
1089 let (in_style, in_width) = match in_elem.sty {
1090 // vectors of pointer-sized integers should've been
1091 // disallowed before here, so this unwrap is safe.
1092 ty::TyInt(i) => (Style::Int(true), i.bit_width().unwrap()),
1093 ty::TyUint(u) => (Style::Int(false), u.bit_width().unwrap()),
1094 ty::TyFloat(f) => (Style::Float, f.bit_width()),
1095 _ => (Style::Unsupported, 0)
1097 let (out_style, out_width) = match out_elem.sty {
1098 ty::TyInt(i) => (Style::Int(true), i.bit_width().unwrap()),
1099 ty::TyUint(u) => (Style::Int(false), u.bit_width().unwrap()),
1100 ty::TyFloat(f) => (Style::Float, f.bit_width()),
1101 _ => (Style::Unsupported, 0)
1104 match (in_style, out_style) {
1105 (Style::Int(in_is_signed), Style::Int(_)) => {
1106 return match in_width.cmp(&out_width) {
1107 Ordering::Greater => bcx.trunc(llargs[0], llret_ty),
1108 Ordering::Equal => llargs[0],
1109 Ordering::Less => if in_is_signed {
1110 bcx.sext(llargs[0], llret_ty)
1112 bcx.zext(llargs[0], llret_ty)
1116 (Style::Int(in_is_signed), Style::Float) => {
1117 return if in_is_signed {
1118 bcx.sitofp(llargs[0], llret_ty)
1120 bcx.uitofp(llargs[0], llret_ty)
1123 (Style::Float, Style::Int(out_is_signed)) => {
1124 return if out_is_signed {
1125 bcx.fptosi(llargs[0], llret_ty)
1127 bcx.fptoui(llargs[0], llret_ty)
1130 (Style::Float, Style::Float) => {
1131 return match in_width.cmp(&out_width) {
1132 Ordering::Greater => bcx.fptrunc(llargs[0], llret_ty),
1133 Ordering::Equal => llargs[0],
1134 Ordering::Less => bcx.fpext(llargs[0], llret_ty)
1137 _ => {/* Unsupported. Fallthrough. */}
1140 "unsupported cast from `{}` with element `{}` to `{}` with element `{}`",
1144 macro_rules! arith {
1145 ($($name: ident: $($($p: ident),* => $call: ident),*;)*) => {
1147 if name == stringify!($name) {
1151 return bcx.$call(llargs[0], llargs[1])
1157 "unsupported operation on `{}` with element `{}`",
1164 simd_add: TyUint, TyInt => add, TyFloat => fadd;
1165 simd_sub: TyUint, TyInt => sub, TyFloat => fsub;
1166 simd_mul: TyUint, TyInt => mul, TyFloat => fmul;
1167 simd_div: TyFloat => fdiv;
1168 simd_shl: TyUint, TyInt => shl;
1169 simd_shr: TyUint => lshr, TyInt => ashr;
1170 simd_and: TyUint, TyInt => and;
1171 simd_or: TyUint, TyInt => or;
1172 simd_xor: TyUint, TyInt => xor;
1174 span_bug!(span, "unknown SIMD intrinsic");
1177 // Returns the width of an int TypeVariant, and if it's signed or not
1178 // Returns None if the type is not an integer
1179 // FIXME: there’s multiple of this functions, investigate using some of the already existing
1181 fn int_type_width_signed<'tcx>(sty: &ty::TypeVariants<'tcx>, ccx: &CrateContext)
1182 -> Option<(u64, bool)> {
1183 use rustc::ty::{TyInt, TyUint};
1185 TyInt(t) => Some((match t {
1187 match &ccx.tcx().sess.target.target.target_pointer_width[..] {
1191 tws => bug!("Unsupported target word size for isize: {}", tws),
1194 ast::IntTy::I8 => 8,
1195 ast::IntTy::I16 => 16,
1196 ast::IntTy::I32 => 32,
1197 ast::IntTy::I64 => 64,
1198 ast::IntTy::I128 => 128,
1200 TyUint(t) => Some((match t {
1201 ast::UintTy::Us => {
1202 match &ccx.tcx().sess.target.target.target_pointer_width[..] {
1206 tws => bug!("Unsupported target word size for usize: {}", tws),
1209 ast::UintTy::U8 => 8,
1210 ast::UintTy::U16 => 16,
1211 ast::UintTy::U32 => 32,
1212 ast::UintTy::U64 => 64,
1213 ast::UintTy::U128 => 128,
1219 // Returns the width of a float TypeVariant
1220 // Returns None if the type is not a float
1221 fn float_type_width<'tcx>(sty: &ty::TypeVariants<'tcx>)
1223 use rustc::ty::TyFloat;
1225 TyFloat(t) => Some(match t {
1226 ast::FloatTy::F32 => 32,
1227 ast::FloatTy::F64 => 64,