1 // Copyright 2012-2015 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 //! Translate the completed AST to the LLVM IR.
13 //! Some functions here, such as trans_block and trans_expr, return a value --
14 //! the result of the translation to LLVM -- while others, such as trans_fn
15 //! and trans_item, are called only for the side effect of adding a
16 //! particular definition to the LLVM IR output we're producing.
18 //! Hopefully useful general knowledge about trans:
20 //! * There's no way to find out the Ty type of a ValueRef. Doing so
21 //! would be "trying to get the eggs out of an omelette" (credit:
22 //! pcwalton). You can, instead, find out its TypeRef by calling val_ty,
23 //! but one TypeRef corresponds to many `Ty`s; for instance, tup(int, int,
24 //! int) and rec(x=int, y=int, z=int) will have the same TypeRef.
26 use super::CrateTranslation;
27 use super::ModuleLlvm;
28 use super::ModuleSource;
29 use super::ModuleTranslation;
31 use assert_module_sources;
33 use back::linker::LinkerInfo;
34 use back::symbol_export::{self, ExportedSymbols};
35 use llvm::{Linkage, ValueRef, Vector, get_param};
37 use rustc::hir::def_id::{DefId, LOCAL_CRATE};
38 use middle::lang_items::StartFnLangItem;
39 use rustc::ty::subst::Substs;
40 use rustc::mir::tcx::LvalueTy;
42 use rustc::ty::{self, Ty, TyCtxt};
43 use rustc::ty::adjustment::CustomCoerceUnsized;
44 use rustc::dep_graph::{DepNode, WorkProduct};
45 use rustc::hir::map as hir_map;
46 use rustc::util::common::time;
47 use session::config::{self, NoDebugInfo};
48 use rustc_incremental::IncrementalHashesMap;
49 use session::{self, DataTypeKind, Session};
50 use abi::{self, FnType};
51 use mir::lvalue::LvalueRef;
56 use common::{C_bool, C_bytes_in_context, C_i32, C_uint};
57 use collector::{self, TransItemCollectionMode};
58 use common::{C_struct_in_context, C_u64, C_undef};
59 use common::CrateContext;
60 use common::{fulfill_obligation};
61 use common::{type_is_zero_size, val_ty};
64 use context::{SharedCrateContext, CrateContextList};
68 use machine::{llalign_of_min, llsize_of};
71 use monomorphize::{self, Instance};
72 use partitioning::{self, PartitioningStrategy, CodegenUnit};
73 use symbol_map::SymbolMap;
74 use symbol_names_test;
75 use trans_item::{TransItem, DefPathBasedNames};
80 use util::nodemap::{NodeSet, FxHashMap, FxHashSet};
83 use std::ffi::{CStr, CString};
87 use syntax_pos::{Span, DUMMY_SP};
90 use rustc::ty::layout::{self, Layout};
93 use mir::lvalue::Alignment;
95 pub struct StatRecorder<'a, 'tcx: 'a> {
96 ccx: &'a CrateContext<'a, 'tcx>,
101 impl<'a, 'tcx> StatRecorder<'a, 'tcx> {
102 pub fn new(ccx: &'a CrateContext<'a, 'tcx>, name: String) -> StatRecorder<'a, 'tcx> {
103 let istart = ccx.stats().n_llvm_insns.get();
112 impl<'a, 'tcx> Drop for StatRecorder<'a, 'tcx> {
114 if self.ccx.sess().trans_stats() {
115 let iend = self.ccx.stats().n_llvm_insns.get();
116 self.ccx.stats().fn_stats.borrow_mut()
117 .push((self.name.take().unwrap(), iend - self.istart));
118 self.ccx.stats().n_fns.set(self.ccx.stats().n_fns.get() + 1);
119 // Reset LLVM insn count to avoid compound costs.
120 self.ccx.stats().n_llvm_insns.set(self.istart);
125 pub fn get_meta(bcx: &Builder, fat_ptr: ValueRef) -> ValueRef {
126 bcx.struct_gep(fat_ptr, abi::FAT_PTR_EXTRA)
129 pub fn get_dataptr(bcx: &Builder, fat_ptr: ValueRef) -> ValueRef {
130 bcx.struct_gep(fat_ptr, abi::FAT_PTR_ADDR)
133 pub fn bin_op_to_icmp_predicate(op: hir::BinOp_,
135 -> llvm::IntPredicate {
137 hir::BiEq => llvm::IntEQ,
138 hir::BiNe => llvm::IntNE,
139 hir::BiLt => if signed { llvm::IntSLT } else { llvm::IntULT },
140 hir::BiLe => if signed { llvm::IntSLE } else { llvm::IntULE },
141 hir::BiGt => if signed { llvm::IntSGT } else { llvm::IntUGT },
142 hir::BiGe => if signed { llvm::IntSGE } else { llvm::IntUGE },
144 bug!("comparison_op_to_icmp_predicate: expected comparison operator, \
151 pub fn bin_op_to_fcmp_predicate(op: hir::BinOp_) -> llvm::RealPredicate {
153 hir::BiEq => llvm::RealOEQ,
154 hir::BiNe => llvm::RealUNE,
155 hir::BiLt => llvm::RealOLT,
156 hir::BiLe => llvm::RealOLE,
157 hir::BiGt => llvm::RealOGT,
158 hir::BiGe => llvm::RealOGE,
160 bug!("comparison_op_to_fcmp_predicate: expected comparison operator, \
167 pub fn compare_simd_types<'a, 'tcx>(
168 bcx: &Builder<'a, 'tcx>,
175 let signed = match t.sty {
177 let cmp = bin_op_to_fcmp_predicate(op);
178 return bcx.sext(bcx.fcmp(cmp, lhs, rhs), ret_ty);
180 ty::TyUint(_) => false,
181 ty::TyInt(_) => true,
182 _ => bug!("compare_simd_types: invalid SIMD type"),
185 let cmp = bin_op_to_icmp_predicate(op, signed);
186 // LLVM outputs an `< size x i1 >`, so we need to perform a sign extension
187 // to get the correctly sized type. This will compile to a single instruction
188 // once the IR is converted to assembly if the SIMD instruction is supported
189 // by the target architecture.
190 bcx.sext(bcx.icmp(cmp, lhs, rhs), ret_ty)
193 /// Retrieve the information we are losing (making dynamic) in an unsizing
196 /// The `old_info` argument is a bit funny. It is intended for use
197 /// in an upcast, where the new vtable for an object will be drived
198 /// from the old one.
199 pub fn unsized_info<'ccx, 'tcx>(ccx: &CrateContext<'ccx, 'tcx>,
202 old_info: Option<ValueRef>)
204 let (source, target) = ccx.tcx().struct_lockstep_tails(source, target);
205 match (&source.sty, &target.sty) {
206 (&ty::TyArray(_, len), &ty::TySlice(_)) => C_uint(ccx, len),
207 (&ty::TyDynamic(..), &ty::TyDynamic(..)) => {
208 // For now, upcasts are limited to changes in marker
209 // traits, and hence never actually require an actual
210 // change to the vtable.
211 old_info.expect("unsized_info: missing old info for trait upcast")
213 (_, &ty::TyDynamic(ref data, ..)) => {
214 consts::ptrcast(meth::get_vtable(ccx, source, data.principal()),
215 Type::vtable_ptr(ccx))
217 _ => bug!("unsized_info: invalid unsizing {:?} -> {:?}",
223 /// Coerce `src` to `dst_ty`. `src_ty` must be a thin pointer.
224 pub fn unsize_thin_ptr<'a, 'tcx>(
225 bcx: &Builder<'a, 'tcx>,
229 ) -> (ValueRef, ValueRef) {
230 debug!("unsize_thin_ptr: {:?} => {:?}", src_ty, dst_ty);
231 match (&src_ty.sty, &dst_ty.sty) {
232 (&ty::TyRef(_, ty::TypeAndMut { ty: a, .. }),
233 &ty::TyRef(_, ty::TypeAndMut { ty: b, .. })) |
234 (&ty::TyRef(_, ty::TypeAndMut { ty: a, .. }),
235 &ty::TyRawPtr(ty::TypeAndMut { ty: b, .. })) |
236 (&ty::TyRawPtr(ty::TypeAndMut { ty: a, .. }),
237 &ty::TyRawPtr(ty::TypeAndMut { ty: b, .. })) => {
238 assert!(bcx.ccx.shared().type_is_sized(a));
239 let ptr_ty = type_of::in_memory_type_of(bcx.ccx, b).ptr_to();
240 (bcx.pointercast(src, ptr_ty), unsized_info(bcx.ccx, a, b, None))
242 (&ty::TyAdt(def_a, _), &ty::TyAdt(def_b, _)) if def_a.is_box() && def_b.is_box() => {
243 let (a, b) = (src_ty.boxed_ty(), dst_ty.boxed_ty());
244 assert!(bcx.ccx.shared().type_is_sized(a));
245 let ptr_ty = type_of::in_memory_type_of(bcx.ccx, b).ptr_to();
246 (bcx.pointercast(src, ptr_ty), unsized_info(bcx.ccx, a, b, None))
248 _ => bug!("unsize_thin_ptr: called on bad types"),
252 /// Coerce `src`, which is a reference to a value of type `src_ty`,
253 /// to a value of type `dst_ty` and store the result in `dst`
254 pub fn coerce_unsized_into<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
255 src: &LvalueRef<'tcx>,
256 dst: &LvalueRef<'tcx>) {
257 let src_ty = src.ty.to_ty(bcx.tcx());
258 let dst_ty = dst.ty.to_ty(bcx.tcx());
259 let coerce_ptr = || {
260 let (base, info) = if common::type_is_fat_ptr(bcx.ccx, src_ty) {
261 // fat-ptr to fat-ptr unsize preserves the vtable
262 // i.e. &'a fmt::Debug+Send => &'a fmt::Debug
263 // So we need to pointercast the base to ensure
264 // the types match up.
265 let (base, info) = load_fat_ptr(bcx, src.llval, src.alignment, src_ty);
266 let llcast_ty = type_of::fat_ptr_base_ty(bcx.ccx, dst_ty);
267 let base = bcx.pointercast(base, llcast_ty);
270 let base = load_ty(bcx, src.llval, src.alignment, src_ty);
271 unsize_thin_ptr(bcx, base, src_ty, dst_ty)
273 store_fat_ptr(bcx, base, info, dst.llval, dst.alignment, dst_ty);
275 match (&src_ty.sty, &dst_ty.sty) {
276 (&ty::TyRef(..), &ty::TyRef(..)) |
277 (&ty::TyRef(..), &ty::TyRawPtr(..)) |
278 (&ty::TyRawPtr(..), &ty::TyRawPtr(..)) => {
281 (&ty::TyAdt(def_a, _), &ty::TyAdt(def_b, _)) if def_a.is_box() && def_b.is_box() => {
285 (&ty::TyAdt(def_a, substs_a), &ty::TyAdt(def_b, substs_b)) => {
286 assert_eq!(def_a, def_b);
288 let src_fields = def_a.variants[0].fields.iter().map(|f| {
289 monomorphize::field_ty(bcx.tcx(), substs_a, f)
291 let dst_fields = def_b.variants[0].fields.iter().map(|f| {
292 monomorphize::field_ty(bcx.tcx(), substs_b, f)
295 let iter = src_fields.zip(dst_fields).enumerate();
296 for (i, (src_fty, dst_fty)) in iter {
297 if type_is_zero_size(bcx.ccx, dst_fty) {
301 let (src_f, src_f_align) = src.trans_field_ptr(bcx, i);
302 let (dst_f, dst_f_align) = dst.trans_field_ptr(bcx, i);
303 if src_fty == dst_fty {
304 memcpy_ty(bcx, dst_f, src_f, src_fty, None);
308 &LvalueRef::new_sized_ty(src_f, src_fty, src_f_align),
309 &LvalueRef::new_sized_ty(dst_f, dst_fty, dst_f_align)
314 _ => bug!("coerce_unsized_into: invalid coercion {:?} -> {:?}",
320 pub fn custom_coerce_unsize_info<'scx, 'tcx>(scx: &SharedCrateContext<'scx, 'tcx>,
323 -> CustomCoerceUnsized {
324 let trait_ref = ty::Binder(ty::TraitRef {
325 def_id: scx.tcx().lang_items.coerce_unsized_trait().unwrap(),
326 substs: scx.tcx().mk_substs_trait(source_ty, &[target_ty])
329 match fulfill_obligation(scx, DUMMY_SP, trait_ref) {
330 traits::VtableImpl(traits::VtableImplData { impl_def_id, .. }) => {
331 scx.tcx().custom_coerce_unsized_kind(impl_def_id)
334 bug!("invalid CoerceUnsized vtable: {:?}", vtable);
339 pub fn cast_shift_expr_rhs(
340 cx: &Builder, op: hir::BinOp_, lhs: ValueRef, rhs: ValueRef
342 cast_shift_rhs(op, lhs, rhs, |a, b| cx.trunc(a, b), |a, b| cx.zext(a, b))
345 pub fn cast_shift_const_rhs(op: hir::BinOp_, lhs: ValueRef, rhs: ValueRef) -> ValueRef {
349 |a, b| unsafe { llvm::LLVMConstTrunc(a, b.to_ref()) },
350 |a, b| unsafe { llvm::LLVMConstZExt(a, b.to_ref()) })
353 fn cast_shift_rhs<F, G>(op: hir::BinOp_,
359 where F: FnOnce(ValueRef, Type) -> ValueRef,
360 G: FnOnce(ValueRef, Type) -> ValueRef
362 // Shifts may have any size int on the rhs
364 let mut rhs_llty = val_ty(rhs);
365 let mut lhs_llty = val_ty(lhs);
366 if rhs_llty.kind() == Vector {
367 rhs_llty = rhs_llty.element_type()
369 if lhs_llty.kind() == Vector {
370 lhs_llty = lhs_llty.element_type()
372 let rhs_sz = rhs_llty.int_width();
373 let lhs_sz = lhs_llty.int_width();
376 } else if lhs_sz > rhs_sz {
377 // FIXME (#1877: If shifting by negative
378 // values becomes not undefined then this is wrong.
388 /// Returns whether this session's target will use SEH-based unwinding.
390 /// This is only true for MSVC targets, and even then the 64-bit MSVC target
391 /// currently uses SEH-ish unwinding with DWARF info tables to the side (same as
392 /// 64-bit MinGW) instead of "full SEH".
393 pub fn wants_msvc_seh(sess: &Session) -> bool {
394 sess.target.target.options.is_like_msvc
397 pub fn call_assume<'a, 'tcx>(b: &Builder<'a, 'tcx>, val: ValueRef) {
398 let assume_intrinsic = b.ccx.get_intrinsic("llvm.assume");
399 b.call(assume_intrinsic, &[val], None);
402 /// Helper for loading values from memory. Does the necessary conversion if the in-memory type
403 /// differs from the type used for SSA values. Also handles various special cases where the type
404 /// gives us better information about what we are loading.
405 pub fn load_ty<'a, 'tcx>(b: &Builder<'a, 'tcx>, ptr: ValueRef,
406 alignment: Alignment, t: Ty<'tcx>) -> ValueRef {
408 if type_is_zero_size(ccx, t) {
409 return C_undef(type_of::type_of(ccx, t));
413 let global = llvm::LLVMIsAGlobalVariable(ptr);
414 if !global.is_null() && llvm::LLVMIsGlobalConstant(global) == llvm::True {
415 let val = llvm::LLVMGetInitializer(global);
418 return llvm::LLVMConstTrunc(val, Type::i1(ccx).to_ref());
426 b.trunc(b.load_range_assert(ptr, 0, 2, llvm::False, alignment.to_align()),
428 } else if t.is_char() {
429 // a char is a Unicode codepoint, and so takes values from 0
430 // to 0x10FFFF inclusive only.
431 b.load_range_assert(ptr, 0, 0x10FFFF + 1, llvm::False, alignment.to_align())
432 } else if (t.is_region_ptr() || t.is_box()) && !common::type_is_fat_ptr(ccx, t) {
433 b.load_nonnull(ptr, alignment.to_align())
435 b.load(ptr, alignment.to_align())
439 /// Helper for storing values in memory. Does the necessary conversion if the in-memory type
440 /// differs from the type used for SSA values.
441 pub fn store_ty<'a, 'tcx>(cx: &Builder<'a, 'tcx>, v: ValueRef, dst: ValueRef,
442 dst_align: Alignment, t: Ty<'tcx>) {
443 debug!("store_ty: {:?} : {:?} <- {:?}", Value(dst), t, Value(v));
445 if common::type_is_fat_ptr(cx.ccx, t) {
446 let lladdr = cx.extract_value(v, abi::FAT_PTR_ADDR);
447 let llextra = cx.extract_value(v, abi::FAT_PTR_EXTRA);
448 store_fat_ptr(cx, lladdr, llextra, dst, dst_align, t);
450 cx.store(from_immediate(cx, v), dst, dst_align.to_align());
454 pub fn store_fat_ptr<'a, 'tcx>(cx: &Builder<'a, 'tcx>,
458 dst_align: Alignment,
460 // FIXME: emit metadata
461 cx.store(data, get_dataptr(cx, dst), dst_align.to_align());
462 cx.store(extra, get_meta(cx, dst), dst_align.to_align());
465 pub fn load_fat_ptr<'a, 'tcx>(
466 b: &Builder<'a, 'tcx>, src: ValueRef, alignment: Alignment, t: Ty<'tcx>
467 ) -> (ValueRef, ValueRef) {
468 let ptr = get_dataptr(b, src);
469 let ptr = if t.is_region_ptr() || t.is_box() {
470 b.load_nonnull(ptr, alignment.to_align())
472 b.load(ptr, alignment.to_align())
475 let meta = get_meta(b, src);
476 let meta_ty = val_ty(meta);
477 // If the 'meta' field is a pointer, it's a vtable, so use load_nonnull
479 let meta = if meta_ty.element_type().kind() == llvm::TypeKind::Pointer {
480 b.load_nonnull(meta, None)
488 pub fn from_immediate(bcx: &Builder, val: ValueRef) -> ValueRef {
489 if val_ty(val) == Type::i1(bcx.ccx) {
490 bcx.zext(val, Type::i8(bcx.ccx))
496 pub fn to_immediate(bcx: &Builder, val: ValueRef, ty: Ty) -> ValueRef {
498 bcx.trunc(val, Type::i1(bcx.ccx))
504 pub enum Lifetime { Start, End }
507 // If LLVM lifetime intrinsic support is enabled (i.e. optimizations
508 // on), and `ptr` is nonzero-sized, then extracts the size of `ptr`
509 // and the intrinsic for `lt` and passes them to `emit`, which is in
510 // charge of generating code to call the passed intrinsic on whatever
511 // block of generated code is targetted for the intrinsic.
513 // If LLVM lifetime intrinsic support is disabled (i.e. optimizations
514 // off) or `ptr` is zero-sized, then no-op (does not call `emit`).
515 pub fn call(self, b: &Builder, ptr: ValueRef) {
516 if b.ccx.sess().opts.optimize == config::OptLevel::No {
520 let size = machine::llsize_of_alloc(b.ccx, val_ty(ptr).element_type());
525 let lifetime_intrinsic = b.ccx.get_intrinsic(match self {
526 Lifetime::Start => "llvm.lifetime.start",
527 Lifetime::End => "llvm.lifetime.end"
530 let ptr = b.pointercast(ptr, Type::i8p(b.ccx));
531 b.call(lifetime_intrinsic, &[C_u64(b.ccx, size), ptr], None);
535 pub fn call_memcpy<'a, 'tcx>(b: &Builder<'a, 'tcx>,
541 let ptr_width = &ccx.sess().target.target.target_pointer_width[..];
542 let key = format!("llvm.memcpy.p0i8.p0i8.i{}", ptr_width);
543 let memcpy = ccx.get_intrinsic(&key);
544 let src_ptr = b.pointercast(src, Type::i8p(ccx));
545 let dst_ptr = b.pointercast(dst, Type::i8p(ccx));
546 let size = b.intcast(n_bytes, ccx.int_type(), false);
547 let align = C_i32(ccx, align as i32);
548 let volatile = C_bool(ccx, false);
549 b.call(memcpy, &[dst_ptr, src_ptr, size, align, volatile], None);
552 pub fn memcpy_ty<'a, 'tcx>(
553 bcx: &Builder<'a, 'tcx>,
561 if type_is_zero_size(ccx, t) {
565 let llty = type_of::type_of(ccx, t);
566 let llsz = llsize_of(ccx, llty);
567 let llalign = align.unwrap_or_else(|| type_of::align_of(ccx, t));
568 call_memcpy(bcx, dst, src, llsz, llalign as u32);
571 pub fn call_memset<'a, 'tcx>(b: &Builder<'a, 'tcx>,
576 volatile: bool) -> ValueRef {
577 let ptr_width = &b.ccx.sess().target.target.target_pointer_width[..];
578 let intrinsic_key = format!("llvm.memset.p0i8.i{}", ptr_width);
579 let llintrinsicfn = b.ccx.get_intrinsic(&intrinsic_key);
580 let volatile = C_bool(b.ccx, volatile);
581 b.call(llintrinsicfn, &[ptr, fill_byte, size, align, volatile], None)
584 pub fn trans_instance<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, instance: Instance<'tcx>) {
585 let _s = if ccx.sess().trans_stats() {
586 let mut instance_name = String::new();
587 DefPathBasedNames::new(ccx.tcx(), true, true)
588 .push_def_path(instance.def, &mut instance_name);
589 Some(StatRecorder::new(ccx, instance_name))
594 // this is an info! to allow collecting monomorphization statistics
595 // and to allow finding the last function before LLVM aborts from
597 info!("trans_instance({})", instance);
599 let fn_ty = ccx.tcx().item_type(instance.def);
600 let fn_ty = ccx.tcx().erase_regions(&fn_ty);
601 let fn_ty = monomorphize::apply_param_substs(ccx.shared(), instance.substs, &fn_ty);
603 let sig = common::ty_fn_sig(ccx, fn_ty);
604 let sig = ccx.tcx().erase_late_bound_regions_and_normalize(&sig);
606 let lldecl = match ccx.instances().borrow().get(&instance) {
608 None => bug!("Instance `{:?}` not already declared", instance)
611 ccx.stats().n_closures.set(ccx.stats().n_closures.get() + 1);
613 if !ccx.sess().no_landing_pads() {
614 attributes::emit_uwtable(lldecl, true);
617 let mir = ccx.tcx().item_mir(instance.def);
618 mir::trans_mir(ccx, lldecl, &mir, instance, sig);
621 pub fn trans_ctor_shim<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
623 substs: &'tcx Substs<'tcx>,
626 attributes::inline(llfn, attributes::InlineAttr::Hint);
627 attributes::set_frame_pointer_elimination(ccx, llfn);
629 let ctor_ty = ccx.tcx().item_type(def_id);
630 let ctor_ty = monomorphize::apply_param_substs(ccx.shared(), substs, &ctor_ty);
632 let sig = ccx.tcx().erase_late_bound_regions_and_normalize(&ctor_ty.fn_sig());
633 let fn_ty = FnType::new(ccx, sig, &[]);
635 let bcx = Builder::new_block(ccx, llfn, "entry-block");
636 if !fn_ty.ret.is_ignore() {
637 // But if there are no nested returns, we skip the indirection
638 // and have a single retslot
639 let dest = if fn_ty.ret.is_indirect() {
642 // We create an alloca to hold a pointer of type `ret.original_ty`
643 // which will hold the pointer to the right alloca which has the
645 bcx.alloca(fn_ty.ret.memory_ty(ccx), "sret_slot")
647 // Can return unsized value
648 let mut dest_val = LvalueRef::new_sized_ty(dest, sig.output(), Alignment::AbiAligned);
649 dest_val.ty = LvalueTy::Downcast {
650 adt_def: sig.output().ty_adt_def().unwrap(),
652 variant_index: disr.0 as usize,
654 let mut llarg_idx = fn_ty.ret.is_indirect() as usize;
656 for (i, arg_ty) in sig.inputs().iter().enumerate() {
657 let (lldestptr, _) = dest_val.trans_field_ptr(&bcx, i);
658 let arg = &fn_ty.args[arg_idx];
660 if common::type_is_fat_ptr(bcx.ccx, arg_ty) {
661 let meta = &fn_ty.args[arg_idx];
663 arg.store_fn_arg(&bcx, &mut llarg_idx, get_dataptr(&bcx, lldestptr));
664 meta.store_fn_arg(&bcx, &mut llarg_idx, get_meta(&bcx, lldestptr));
666 arg.store_fn_arg(&bcx, &mut llarg_idx, lldestptr);
669 adt::trans_set_discr(&bcx, sig.output(), dest, disr);
671 if fn_ty.ret.is_indirect() {
676 if let Some(cast_ty) = fn_ty.ret.cast {
678 bcx.pointercast(dest, cast_ty.ptr_to()),
679 Some(llalign_of_min(ccx, fn_ty.ret.ty))
682 bcx.ret(bcx.load(dest, None))
689 pub fn llvm_linkage_by_name(name: &str) -> Option<Linkage> {
690 // Use the names from src/llvm/docs/LangRef.rst here. Most types are only
691 // applicable to variable declarations and may not really make sense for
692 // Rust code in the first place but whitelist them anyway and trust that
693 // the user knows what s/he's doing. Who knows, unanticipated use cases
694 // may pop up in the future.
696 // ghost, dllimport, dllexport and linkonce_odr_autohide are not supported
697 // and don't have to be, LLVM treats them as no-ops.
699 "appending" => Some(llvm::Linkage::AppendingLinkage),
700 "available_externally" => Some(llvm::Linkage::AvailableExternallyLinkage),
701 "common" => Some(llvm::Linkage::CommonLinkage),
702 "extern_weak" => Some(llvm::Linkage::ExternalWeakLinkage),
703 "external" => Some(llvm::Linkage::ExternalLinkage),
704 "internal" => Some(llvm::Linkage::InternalLinkage),
705 "linkonce" => Some(llvm::Linkage::LinkOnceAnyLinkage),
706 "linkonce_odr" => Some(llvm::Linkage::LinkOnceODRLinkage),
707 "private" => Some(llvm::Linkage::PrivateLinkage),
708 "weak" => Some(llvm::Linkage::WeakAnyLinkage),
709 "weak_odr" => Some(llvm::Linkage::WeakODRLinkage),
714 pub fn set_link_section(ccx: &CrateContext,
716 attrs: &[ast::Attribute]) {
717 if let Some(sect) = attr::first_attr_value_str_by_name(attrs, "link_section") {
718 if contains_null(§.as_str()) {
719 ccx.sess().fatal(&format!("Illegal null byte in link_section value: `{}`", §));
722 let buf = CString::new(sect.as_str().as_bytes()).unwrap();
723 llvm::LLVMSetSection(llval, buf.as_ptr());
728 /// Create the `main` function which will initialise the rust runtime and call
729 /// users’ main function.
730 pub fn maybe_create_entry_wrapper(ccx: &CrateContext) {
731 let (main_def_id, span) = match *ccx.sess().entry_fn.borrow() {
732 Some((id, span)) => {
733 (ccx.tcx().hir.local_def_id(id), span)
738 // check for the #[rustc_error] annotation, which forces an
739 // error in trans. This is used to write compile-fail tests
740 // that actually test that compilation succeeds without
741 // reporting an error.
742 if ccx.tcx().has_attr(main_def_id, "rustc_error") {
743 ccx.tcx().sess.span_fatal(span, "compilation successful");
746 let instance = Instance::mono(ccx.shared(), main_def_id);
748 if !ccx.codegen_unit().contains_item(&TransItem::Fn(instance)) {
749 // We want to create the wrapper in the same codegen unit as Rust's main
754 let main_llfn = Callee::def(ccx, main_def_id, instance.substs).reify(ccx);
756 let et = ccx.sess().entry_type.get().unwrap();
758 config::EntryMain => create_entry_fn(ccx, span, main_llfn, true),
759 config::EntryStart => create_entry_fn(ccx, span, main_llfn, false),
760 config::EntryNone => {} // Do nothing.
763 fn create_entry_fn(ccx: &CrateContext,
766 use_start_lang_item: bool) {
767 let llfty = Type::func(&[ccx.int_type(), Type::i8p(ccx).ptr_to()], &ccx.int_type());
769 if declare::get_defined_value(ccx, "main").is_some() {
770 // FIXME: We should be smart and show a better diagnostic here.
771 ccx.sess().struct_span_err(sp, "entry symbol `main` defined multiple times")
772 .help("did you use #[no_mangle] on `fn main`? Use #[start] instead")
774 ccx.sess().abort_if_errors();
777 let llfn = declare::declare_cfn(ccx, "main", llfty);
779 // `main` should respect same config for frame pointer elimination as rest of code
780 attributes::set_frame_pointer_elimination(ccx, llfn);
782 let bld = Builder::new_block(ccx, llfn, "top");
784 debuginfo::gdb::insert_reference_to_gdb_debug_scripts_section_global(ccx, &bld);
786 let (start_fn, args) = if use_start_lang_item {
787 let start_def_id = ccx.tcx().require_lang_item(StartFnLangItem);
788 let empty_substs = ccx.tcx().intern_substs(&[]);
789 let start_fn = Callee::def(ccx, start_def_id, empty_substs).reify(ccx);
790 (start_fn, vec![bld.pointercast(rust_main, Type::i8p(ccx).ptr_to()), get_param(llfn, 0),
793 debug!("using user-defined start fn");
794 (rust_main, vec![get_param(llfn, 0 as c_uint), get_param(llfn, 1 as c_uint)])
797 let result = bld.call(start_fn, &args, None);
802 fn contains_null(s: &str) -> bool {
803 s.bytes().any(|b| b == 0)
806 fn write_metadata(cx: &SharedCrateContext,
807 exported_symbols: &NodeSet) -> Vec<u8> {
810 #[derive(PartialEq, Eq, PartialOrd, Ord)]
817 let kind = cx.sess().crate_types.borrow().iter().map(|ty| {
819 config::CrateTypeExecutable |
820 config::CrateTypeStaticlib |
821 config::CrateTypeCdylib => MetadataKind::None,
823 config::CrateTypeRlib => MetadataKind::Uncompressed,
825 config::CrateTypeDylib |
826 config::CrateTypeProcMacro => MetadataKind::Compressed,
830 if kind == MetadataKind::None {
834 let cstore = &cx.tcx().sess.cstore;
835 let metadata = cstore.encode_metadata(cx.tcx(),
839 if kind == MetadataKind::Uncompressed {
843 assert!(kind == MetadataKind::Compressed);
844 let mut compressed = cstore.metadata_encoding_version().to_vec();
845 compressed.extend_from_slice(&flate::deflate_bytes(&metadata));
847 let llmeta = C_bytes_in_context(cx.metadata_llcx(), &compressed[..]);
848 let llconst = C_struct_in_context(cx.metadata_llcx(), &[llmeta], false);
849 let name = cx.metadata_symbol_name();
850 let buf = CString::new(name).unwrap();
851 let llglobal = unsafe {
852 llvm::LLVMAddGlobal(cx.metadata_llmod(), val_ty(llconst).to_ref(), buf.as_ptr())
855 llvm::LLVMSetInitializer(llglobal, llconst);
857 cx.tcx().sess.cstore.metadata_section_name(&cx.sess().target.target);
858 let name = CString::new(section_name).unwrap();
859 llvm::LLVMSetSection(llglobal, name.as_ptr());
861 // Also generate a .section directive to force no
862 // flags, at least for ELF outputs, so that the
863 // metadata doesn't get loaded into memory.
864 let directive = format!(".section {}", section_name);
865 let directive = CString::new(directive).unwrap();
866 llvm::LLVMSetModuleInlineAsm(cx.metadata_llmod(), directive.as_ptr())
871 /// Find any symbols that are defined in one compilation unit, but not declared
872 /// in any other compilation unit. Give these symbols internal linkage.
873 fn internalize_symbols<'a, 'tcx>(sess: &Session,
874 ccxs: &CrateContextList<'a, 'tcx>,
875 symbol_map: &SymbolMap<'tcx>,
876 exported_symbols: &ExportedSymbols) {
877 let export_threshold =
878 symbol_export::crates_export_threshold(&sess.crate_types.borrow()[..]);
880 let exported_symbols = exported_symbols
881 .exported_symbols(LOCAL_CRATE)
883 .filter(|&&(_, export_level)| {
884 symbol_export::is_below_threshold(export_level, export_threshold)
886 .map(|&(ref name, _)| &name[..])
887 .collect::<FxHashSet<&str>>();
889 let scx = ccxs.shared();
892 let incr_comp = sess.opts.debugging_opts.incremental.is_some();
894 // 'unsafe' because we are holding on to CStr's from the LLVM module within
897 let mut referenced_somewhere = FxHashSet();
899 // Collect all symbols that need to stay externally visible because they
900 // are referenced via a declaration in some other codegen unit. In
901 // incremental compilation, we don't need to collect. See below for more
904 for ccx in ccxs.iter_need_trans() {
905 for val in iter_globals(ccx.llmod()).chain(iter_functions(ccx.llmod())) {
906 let linkage = llvm::LLVMRustGetLinkage(val);
907 // We only care about external declarations (not definitions)
908 // and available_externally definitions.
909 let is_available_externally =
910 linkage == llvm::Linkage::AvailableExternallyLinkage;
911 let is_decl = llvm::LLVMIsDeclaration(val) == llvm::True;
913 if is_decl || is_available_externally {
914 let symbol_name = CStr::from_ptr(llvm::LLVMGetValueName(val));
915 referenced_somewhere.insert(symbol_name);
921 // Also collect all symbols for which we cannot adjust linkage, because
922 // it is fixed by some directive in the source code.
923 let (locally_defined_symbols, linkage_fixed_explicitly) = {
924 let mut locally_defined_symbols = FxHashSet();
925 let mut linkage_fixed_explicitly = FxHashSet();
927 for trans_item in scx.translation_items().borrow().iter() {
928 let symbol_name = symbol_map.get_or_compute(scx, *trans_item);
929 if trans_item.explicit_linkage(tcx).is_some() {
930 linkage_fixed_explicitly.insert(symbol_name.clone());
932 locally_defined_symbols.insert(symbol_name);
935 (locally_defined_symbols, linkage_fixed_explicitly)
938 // Examine each external definition. If the definition is not used in
939 // any other compilation unit, and is not reachable from other crates,
940 // then give it internal linkage.
941 for ccx in ccxs.iter_need_trans() {
942 for val in iter_globals(ccx.llmod()).chain(iter_functions(ccx.llmod())) {
943 let linkage = llvm::LLVMRustGetLinkage(val);
945 let is_externally_visible = (linkage == llvm::Linkage::ExternalLinkage) ||
946 (linkage == llvm::Linkage::LinkOnceODRLinkage) ||
947 (linkage == llvm::Linkage::WeakODRLinkage);
949 if !is_externally_visible {
950 // This symbol is not visible outside of its codegen unit,
951 // so there is nothing to do for it.
955 let name_cstr = CStr::from_ptr(llvm::LLVMGetValueName(val));
956 let name_str = name_cstr.to_str().unwrap();
958 if exported_symbols.contains(&name_str) {
959 // This symbol is explicitly exported, so we can't
960 // mark it as internal or hidden.
964 let is_declaration = llvm::LLVMIsDeclaration(val) == llvm::True;
967 if locally_defined_symbols.contains(name_str) {
968 // Only mark declarations from the current crate as hidden.
969 // Otherwise we would mark things as hidden that are
970 // imported from other crates or native libraries.
971 llvm::LLVMRustSetVisibility(val, llvm::Visibility::Hidden);
974 let has_fixed_linkage = linkage_fixed_explicitly.contains(name_str);
976 if !has_fixed_linkage {
977 // In incremental compilation mode, we can't be sure that
978 // we saw all references because we don't know what's in
979 // cached compilation units, so we always assume that the
980 // given item has been referenced.
981 if incr_comp || referenced_somewhere.contains(&name_cstr) {
982 llvm::LLVMRustSetVisibility(val, llvm::Visibility::Hidden);
984 llvm::LLVMRustSetLinkage(val, llvm::Linkage::InternalLinkage);
987 llvm::LLVMSetDLLStorageClass(val, llvm::DLLStorageClass::Default);
988 llvm::UnsetComdat(val);
996 // Create a `__imp_<symbol> = &symbol` global for every public static `symbol`.
997 // This is required to satisfy `dllimport` references to static data in .rlibs
998 // when using MSVC linker. We do this only for data, as linker can fix up
999 // code references on its own.
1000 // See #26591, #27438
1001 fn create_imps(cx: &CrateContextList) {
1002 // The x86 ABI seems to require that leading underscores are added to symbol
1003 // names, so we need an extra underscore on 32-bit. There's also a leading
1004 // '\x01' here which disables LLVM's symbol mangling (e.g. no extra
1005 // underscores added in front).
1006 let prefix = if cx.shared().sess().target.target.target_pointer_width == "32" {
1012 for ccx in cx.iter_need_trans() {
1013 let exported: Vec<_> = iter_globals(ccx.llmod())
1015 llvm::LLVMRustGetLinkage(val) ==
1016 llvm::Linkage::ExternalLinkage &&
1017 llvm::LLVMIsDeclaration(val) == 0
1021 let i8p_ty = Type::i8p(&ccx);
1022 for val in exported {
1023 let name = CStr::from_ptr(llvm::LLVMGetValueName(val));
1024 let mut imp_name = prefix.as_bytes().to_vec();
1025 imp_name.extend(name.to_bytes());
1026 let imp_name = CString::new(imp_name).unwrap();
1027 let imp = llvm::LLVMAddGlobal(ccx.llmod(),
1029 imp_name.as_ptr() as *const _);
1030 let init = llvm::LLVMConstBitCast(val, i8p_ty.to_ref());
1031 llvm::LLVMSetInitializer(imp, init);
1032 llvm::LLVMRustSetLinkage(imp, llvm::Linkage::ExternalLinkage);
1040 step: unsafe extern "C" fn(ValueRef) -> ValueRef,
1043 impl Iterator for ValueIter {
1044 type Item = ValueRef;
1046 fn next(&mut self) -> Option<ValueRef> {
1049 self.cur = unsafe { (self.step)(old) };
1057 fn iter_globals(llmod: llvm::ModuleRef) -> ValueIter {
1060 cur: llvm::LLVMGetFirstGlobal(llmod),
1061 step: llvm::LLVMGetNextGlobal,
1066 fn iter_functions(llmod: llvm::ModuleRef) -> ValueIter {
1069 cur: llvm::LLVMGetFirstFunction(llmod),
1070 step: llvm::LLVMGetNextFunction,
1075 /// The context provided lists a set of reachable ids as calculated by
1076 /// middle::reachable, but this contains far more ids and symbols than we're
1077 /// actually exposing from the object file. This function will filter the set in
1078 /// the context to the set of ids which correspond to symbols that are exposed
1079 /// from the object file being generated.
1081 /// This list is later used by linkers to determine the set of symbols needed to
1082 /// be exposed from a dynamic library and it's also encoded into the metadata.
1083 pub fn find_exported_symbols(tcx: TyCtxt, reachable: NodeSet) -> NodeSet {
1084 reachable.into_iter().filter(|&id| {
1085 // Next, we want to ignore some FFI functions that are not exposed from
1086 // this crate. Reachable FFI functions can be lumped into two
1089 // 1. Those that are included statically via a static library
1090 // 2. Those included otherwise (e.g. dynamically or via a framework)
1092 // Although our LLVM module is not literally emitting code for the
1093 // statically included symbols, it's an export of our library which
1094 // needs to be passed on to the linker and encoded in the metadata.
1096 // As a result, if this id is an FFI item (foreign item) then we only
1097 // let it through if it's included statically.
1098 match tcx.hir.get(id) {
1099 hir_map::NodeForeignItem(..) => {
1100 let def_id = tcx.hir.local_def_id(id);
1101 tcx.sess.cstore.is_statically_included_foreign_item(def_id)
1104 // Only consider nodes that actually have exported symbols.
1105 hir_map::NodeItem(&hir::Item {
1106 node: hir::ItemStatic(..), .. }) |
1107 hir_map::NodeItem(&hir::Item {
1108 node: hir::ItemFn(..), .. }) |
1109 hir_map::NodeImplItem(&hir::ImplItem {
1110 node: hir::ImplItemKind::Method(..), .. }) => {
1111 let def_id = tcx.hir.local_def_id(id);
1112 let generics = tcx.item_generics(def_id);
1113 let attributes = tcx.get_attrs(def_id);
1114 (generics.parent_types == 0 && generics.types.is_empty()) &&
1115 // Functions marked with #[inline] are only ever translated
1116 // with "internal" linkage and are never exported.
1117 !attr::requests_inline(&attributes[..])
1125 pub fn trans_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
1126 analysis: ty::CrateAnalysis,
1127 incremental_hashes_map: &IncrementalHashesMap)
1128 -> CrateTranslation {
1129 let _task = tcx.dep_graph.in_task(DepNode::TransCrate);
1131 // Be careful with this krate: obviously it gives access to the
1132 // entire contents of the krate. So if you push any subtasks of
1133 // `TransCrate`, you need to be careful to register "reads" of the
1134 // particular items that will be processed.
1135 let krate = tcx.hir.krate();
1137 let ty::CrateAnalysis { export_map, reachable, name, .. } = analysis;
1138 let exported_symbols = find_exported_symbols(tcx, reachable);
1140 let check_overflow = tcx.sess.overflow_checks();
1142 let link_meta = link::build_link_meta(incremental_hashes_map, &name);
1144 let shared_ccx = SharedCrateContext::new(tcx,
1149 // Translate the metadata.
1150 let metadata = time(tcx.sess.time_passes(), "write metadata", || {
1151 write_metadata(&shared_ccx, shared_ccx.exported_symbols())
1154 let metadata_module = ModuleTranslation {
1155 name: link::METADATA_MODULE_NAME.to_string(),
1156 symbol_name_hash: 0, // we always rebuild metadata, at least for now
1157 source: ModuleSource::Translated(ModuleLlvm {
1158 llcx: shared_ccx.metadata_llcx(),
1159 llmod: shared_ccx.metadata_llmod(),
1162 let no_builtins = attr::contains_name(&krate.attrs, "no_builtins");
1164 // Skip crate items and just output metadata in -Z no-trans mode.
1165 if tcx.sess.opts.debugging_opts.no_trans ||
1166 !tcx.sess.opts.output_types.should_trans() {
1167 let empty_exported_symbols = ExportedSymbols::empty();
1168 let linker_info = LinkerInfo::new(&shared_ccx, &empty_exported_symbols);
1169 return CrateTranslation {
1171 metadata_module: metadata_module,
1174 exported_symbols: empty_exported_symbols,
1175 no_builtins: no_builtins,
1176 linker_info: linker_info,
1177 windows_subsystem: None,
1181 // Run the translation item collector and partition the collected items into
1183 let (codegen_units, symbol_map) = collect_and_partition_translation_items(&shared_ccx);
1185 let symbol_map = Rc::new(symbol_map);
1187 let previous_work_products = trans_reuse_previous_work_products(&shared_ccx,
1191 let crate_context_list = CrateContextList::new(&shared_ccx,
1193 previous_work_products,
1194 symbol_map.clone());
1195 let modules: Vec<_> = crate_context_list.iter_all()
1197 let source = match ccx.previous_work_product() {
1198 Some(buf) => ModuleSource::Preexisting(buf.clone()),
1199 None => ModuleSource::Translated(ModuleLlvm {
1206 name: String::from(ccx.codegen_unit().name()),
1207 symbol_name_hash: ccx.codegen_unit()
1208 .compute_symbol_name_hash(&shared_ccx,
1215 assert_module_sources::assert_module_sources(tcx, &modules);
1217 // Instantiate translation items without filling out definitions yet...
1218 for ccx in crate_context_list.iter_need_trans() {
1219 let cgu = ccx.codegen_unit();
1220 let trans_items = cgu.items_in_deterministic_order(tcx, &symbol_map);
1222 tcx.dep_graph.with_task(cgu.work_product_dep_node(), || {
1223 for (trans_item, linkage) in trans_items {
1224 trans_item.predefine(&ccx, linkage);
1229 // ... and now that we have everything pre-defined, fill out those definitions.
1230 for ccx in crate_context_list.iter_need_trans() {
1231 let cgu = ccx.codegen_unit();
1232 let trans_items = cgu.items_in_deterministic_order(tcx, &symbol_map);
1233 tcx.dep_graph.with_task(cgu.work_product_dep_node(), || {
1234 for (trans_item, _) in trans_items {
1235 trans_item.define(&ccx);
1238 // If this codegen unit contains the main function, also create the
1240 maybe_create_entry_wrapper(&ccx);
1242 // Run replace-all-uses-with for statics that need it
1243 for &(old_g, new_g) in ccx.statics_to_rauw().borrow().iter() {
1245 let bitcast = llvm::LLVMConstPointerCast(new_g, llvm::LLVMTypeOf(old_g));
1246 llvm::LLVMReplaceAllUsesWith(old_g, bitcast);
1247 llvm::LLVMDeleteGlobal(old_g);
1251 // Finalize debuginfo
1252 if ccx.sess().opts.debuginfo != NoDebugInfo {
1253 debuginfo::finalize(&ccx);
1258 symbol_names_test::report_symbol_names(&shared_ccx);
1260 if shared_ccx.sess().trans_stats() {
1261 let stats = shared_ccx.stats();
1262 println!("--- trans stats ---");
1263 println!("n_glues_created: {}", stats.n_glues_created.get());
1264 println!("n_null_glues: {}", stats.n_null_glues.get());
1265 println!("n_real_glues: {}", stats.n_real_glues.get());
1267 println!("n_fns: {}", stats.n_fns.get());
1268 println!("n_inlines: {}", stats.n_inlines.get());
1269 println!("n_closures: {}", stats.n_closures.get());
1270 println!("fn stats:");
1271 stats.fn_stats.borrow_mut().sort_by(|&(_, insns_a), &(_, insns_b)| {
1272 insns_b.cmp(&insns_a)
1274 for tuple in stats.fn_stats.borrow().iter() {
1276 (ref name, insns) => {
1277 println!("{} insns, {}", insns, *name);
1283 if shared_ccx.sess().count_llvm_insns() {
1284 for (k, v) in shared_ccx.stats().llvm_insns.borrow().iter() {
1285 println!("{:7} {}", *v, *k);
1289 let sess = shared_ccx.sess();
1291 let exported_symbols = ExportedSymbols::compute_from(&shared_ccx,
1294 // Now that we have all symbols that are exported from the CGUs of this
1295 // crate, we can run the `internalize_symbols` pass.
1296 time(shared_ccx.sess().time_passes(), "internalize symbols", || {
1297 internalize_symbols(sess,
1298 &crate_context_list,
1303 if tcx.sess.opts.debugging_opts.print_type_sizes {
1304 gather_type_sizes(tcx);
1307 if sess.target.target.options.is_like_msvc &&
1308 sess.crate_types.borrow().iter().any(|ct| *ct == config::CrateTypeRlib) {
1309 create_imps(&crate_context_list);
1312 let linker_info = LinkerInfo::new(&shared_ccx, &exported_symbols);
1314 let subsystem = attr::first_attr_value_str_by_name(&krate.attrs,
1315 "windows_subsystem");
1316 let windows_subsystem = subsystem.map(|subsystem| {
1317 if subsystem != "windows" && subsystem != "console" {
1318 tcx.sess.fatal(&format!("invalid windows subsystem `{}`, only \
1319 `windows` and `console` are allowed",
1322 subsystem.to_string()
1327 metadata_module: metadata_module,
1330 exported_symbols: exported_symbols,
1331 no_builtins: no_builtins,
1332 linker_info: linker_info,
1333 windows_subsystem: windows_subsystem,
1337 fn gather_type_sizes<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
1338 let layout_cache = tcx.layout_cache.borrow();
1339 for (ty, layout) in layout_cache.iter() {
1341 // (delay format until we actually need it)
1342 let record = |kind, opt_discr_size, variants| {
1343 let type_desc = format!("{:?}", ty);
1344 let overall_size = layout.size(&tcx.data_layout);
1345 let align = layout.align(&tcx.data_layout);
1346 tcx.sess.code_stats.borrow_mut().record_type_size(kind,
1354 let (adt_def, substs) = match ty.sty {
1355 ty::TyAdt(ref adt_def, substs) => {
1356 debug!("print-type-size t: `{:?}` process adt", ty);
1360 ty::TyClosure(..) => {
1361 debug!("print-type-size t: `{:?}` record closure", ty);
1362 record(DataTypeKind::Closure, None, vec![]);
1367 debug!("print-type-size t: `{:?}` skip non-nominal", ty);
1372 let adt_kind = adt_def.adt_kind();
1374 let build_field_info = |(field_name, field_ty): (ast::Name, Ty), offset: &layout::Size| {
1375 match layout_cache.get(&field_ty) {
1376 None => bug!("no layout found for field {} type: `{:?}`", field_name, field_ty),
1377 Some(field_layout) => {
1378 session::FieldInfo {
1379 name: field_name.to_string(),
1380 offset: offset.bytes(),
1381 size: field_layout.size(&tcx.data_layout).bytes(),
1382 align: field_layout.align(&tcx.data_layout).abi(),
1388 let build_primitive_info = |name: ast::Name, value: &layout::Primitive| {
1389 session::VariantInfo {
1390 name: Some(name.to_string()),
1391 kind: session::SizeKind::Exact,
1392 align: value.align(&tcx.data_layout).abi(),
1393 size: value.size(&tcx.data_layout).bytes(),
1399 WithDiscrim(&'a layout::Struct),
1400 NoDiscrim(&'a layout::Struct),
1403 let build_variant_info = |n: Option<ast::Name>, flds: &[(ast::Name, Ty)], layout: Fields| {
1404 let (s, field_offsets) = match layout {
1405 Fields::WithDiscrim(s) => (s, &s.offsets[1..]),
1406 Fields::NoDiscrim(s) => (s, &s.offsets[0..]),
1408 let field_info: Vec<_> = flds.iter()
1409 .zip(field_offsets.iter())
1410 .map(|(&field_name_ty, offset)| build_field_info(field_name_ty, offset))
1413 session::VariantInfo {
1414 name: n.map(|n|n.to_string()),
1416 session::SizeKind::Exact
1418 session::SizeKind::Min
1420 align: s.align.abi(),
1421 size: s.min_size.bytes(),
1427 Layout::StructWrappedNullablePointer { nonnull: ref variant_layout,
1430 discrfield_source: _ } => {
1431 debug!("print-type-size t: `{:?}` adt struct-wrapped nullable nndiscr {} is {:?}",
1432 ty, nndiscr, variant_layout);
1433 let variant_def = &adt_def.variants[nndiscr as usize];
1434 let fields: Vec<_> = variant_def.fields.iter()
1435 .map(|field_def| (field_def.name, field_def.ty(tcx, substs)))
1437 record(adt_kind.into(),
1439 vec![build_variant_info(Some(variant_def.name),
1441 Fields::NoDiscrim(variant_layout))]);
1443 Layout::RawNullablePointer { nndiscr, value } => {
1444 debug!("print-type-size t: `{:?}` adt raw nullable nndiscr {} is {:?}",
1445 ty, nndiscr, value);
1446 let variant_def = &adt_def.variants[nndiscr as usize];
1447 record(adt_kind.into(), None,
1448 vec![build_primitive_info(variant_def.name, &value)]);
1450 Layout::Univariant { variant: ref variant_layout, non_zero: _ } => {
1451 let variant_names = || {
1452 adt_def.variants.iter().map(|v|format!("{}", v.name)).collect::<Vec<_>>()
1454 debug!("print-type-size t: `{:?}` adt univariant {:?} variants: {:?}",
1455 ty, variant_layout, variant_names());
1456 assert!(adt_def.variants.len() <= 1,
1457 "univariant with variants {:?}", variant_names());
1458 if adt_def.variants.len() == 1 {
1459 let variant_def = &adt_def.variants[0];
1460 let fields: Vec<_> = variant_def.fields.iter()
1461 .map(|field_def| (field_def.name, field_def.ty(tcx, substs)))
1463 record(adt_kind.into(),
1465 vec![build_variant_info(Some(variant_def.name),
1467 Fields::NoDiscrim(variant_layout))]);
1469 // (This case arises for *empty* enums; so give it
1471 record(adt_kind.into(), None, vec![]);
1475 Layout::General { ref variants, discr, .. } => {
1476 debug!("print-type-size t: `{:?}` adt general variants def {} layouts {} {:?}",
1477 ty, adt_def.variants.len(), variants.len(), variants);
1478 let variant_infos: Vec<_> = adt_def.variants.iter()
1479 .zip(variants.iter())
1480 .map(|(variant_def, variant_layout)| {
1481 let fields: Vec<_> = variant_def.fields.iter()
1482 .map(|field_def| (field_def.name, field_def.ty(tcx, substs)))
1484 build_variant_info(Some(variant_def.name),
1486 Fields::WithDiscrim(variant_layout))
1489 record(adt_kind.into(), Some(discr.size()), variant_infos);
1492 Layout::UntaggedUnion { ref variants } => {
1493 debug!("print-type-size t: `{:?}` adt union variants {:?}",
1495 // layout does not currently store info about each
1497 record(adt_kind.into(), None, Vec::new());
1500 Layout::CEnum { discr, .. } => {
1501 debug!("print-type-size t: `{:?}` adt c-like enum", ty);
1502 let variant_infos: Vec<_> = adt_def.variants.iter()
1503 .map(|variant_def| {
1504 build_primitive_info(variant_def.name,
1505 &layout::Primitive::Int(discr))
1508 record(adt_kind.into(), Some(discr.size()), variant_infos);
1511 // other cases provide little interesting (i.e. adjustable
1512 // via representation tweaks) size info beyond total size.
1513 Layout::Scalar { .. } |
1514 Layout::Vector { .. } |
1515 Layout::Array { .. } |
1516 Layout::FatPointer { .. } => {
1517 debug!("print-type-size t: `{:?}` adt other", ty);
1518 record(adt_kind.into(), None, Vec::new())
1524 /// For each CGU, identify if we can reuse an existing object file (or
1525 /// maybe other context).
1526 fn trans_reuse_previous_work_products(scx: &SharedCrateContext,
1527 codegen_units: &[CodegenUnit],
1528 symbol_map: &SymbolMap)
1529 -> Vec<Option<WorkProduct>> {
1530 debug!("trans_reuse_previous_work_products()");
1534 let id = cgu.work_product_id();
1536 let hash = cgu.compute_symbol_name_hash(scx, symbol_map);
1538 debug!("trans_reuse_previous_work_products: id={:?} hash={}", id, hash);
1540 if let Some(work_product) = scx.dep_graph().previous_work_product(&id) {
1541 if work_product.input_hash == hash {
1542 debug!("trans_reuse_previous_work_products: reusing {:?}", work_product);
1543 return Some(work_product);
1545 if scx.sess().opts.debugging_opts.incremental_info {
1546 println!("incremental: CGU `{}` invalidated because of \
1547 changed partitioning hash.",
1550 debug!("trans_reuse_previous_work_products: \
1551 not reusing {:?} because hash changed to {:?}",
1552 work_product, hash);
1561 fn collect_and_partition_translation_items<'a, 'tcx>(scx: &SharedCrateContext<'a, 'tcx>)
1562 -> (Vec<CodegenUnit<'tcx>>, SymbolMap<'tcx>) {
1563 let time_passes = scx.sess().time_passes();
1565 let collection_mode = match scx.sess().opts.debugging_opts.print_trans_items {
1567 let mode_string = s.to_lowercase();
1568 let mode_string = mode_string.trim();
1569 if mode_string == "eager" {
1570 TransItemCollectionMode::Eager
1572 if mode_string != "lazy" {
1573 let message = format!("Unknown codegen-item collection mode '{}'. \
1574 Falling back to 'lazy' mode.",
1576 scx.sess().warn(&message);
1579 TransItemCollectionMode::Lazy
1582 None => TransItemCollectionMode::Lazy
1585 let (items, inlining_map) =
1586 time(time_passes, "translation item collection", || {
1587 collector::collect_crate_translation_items(&scx, collection_mode)
1590 let symbol_map = SymbolMap::build(scx, items.iter().cloned());
1592 let strategy = if scx.sess().opts.debugging_opts.incremental.is_some() {
1593 PartitioningStrategy::PerModule
1595 PartitioningStrategy::FixedUnitCount(scx.sess().opts.cg.codegen_units)
1598 let codegen_units = time(time_passes, "codegen unit partitioning", || {
1599 partitioning::partition(scx,
1600 items.iter().cloned(),
1605 assert!(scx.tcx().sess.opts.cg.codegen_units == codegen_units.len() ||
1606 scx.tcx().sess.opts.debugging_opts.incremental.is_some());
1609 let mut ccx_map = scx.translation_items().borrow_mut();
1611 for trans_item in items.iter().cloned() {
1612 ccx_map.insert(trans_item);
1616 if scx.sess().opts.debugging_opts.print_trans_items.is_some() {
1617 let mut item_to_cgus = FxHashMap();
1619 for cgu in &codegen_units {
1620 for (&trans_item, &linkage) in cgu.items() {
1621 item_to_cgus.entry(trans_item)
1622 .or_insert(Vec::new())
1623 .push((cgu.name().clone(), linkage));
1627 let mut item_keys: Vec<_> = items
1630 let mut output = i.to_string(scx.tcx());
1631 output.push_str(" @@");
1632 let mut empty = Vec::new();
1633 let mut cgus = item_to_cgus.get_mut(i).unwrap_or(&mut empty);
1634 cgus.as_mut_slice().sort_by_key(|&(ref name, _)| name.clone());
1636 for &(ref cgu_name, linkage) in cgus.iter() {
1637 output.push_str(" ");
1638 output.push_str(&cgu_name[..]);
1640 let linkage_abbrev = match linkage {
1641 llvm::Linkage::ExternalLinkage => "External",
1642 llvm::Linkage::AvailableExternallyLinkage => "Available",
1643 llvm::Linkage::LinkOnceAnyLinkage => "OnceAny",
1644 llvm::Linkage::LinkOnceODRLinkage => "OnceODR",
1645 llvm::Linkage::WeakAnyLinkage => "WeakAny",
1646 llvm::Linkage::WeakODRLinkage => "WeakODR",
1647 llvm::Linkage::AppendingLinkage => "Appending",
1648 llvm::Linkage::InternalLinkage => "Internal",
1649 llvm::Linkage::PrivateLinkage => "Private",
1650 llvm::Linkage::ExternalWeakLinkage => "ExternalWeak",
1651 llvm::Linkage::CommonLinkage => "Common",
1654 output.push_str("[");
1655 output.push_str(linkage_abbrev);
1656 output.push_str("]");
1664 for item in item_keys {
1665 println!("TRANS_ITEM {}", item);
1669 (codegen_units, symbol_map)