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::LOCAL_CRATE;
38 use middle::lang_items::StartFnLangItem;
40 use rustc::ty::{self, Ty, TyCtxt};
41 use rustc::ty::adjustment::CustomCoerceUnsized;
42 use rustc::dep_graph::{AssertDepGraphSafe, DepNode, WorkProduct};
43 use rustc::hir::map as hir_map;
44 use rustc::util::common::time;
45 use session::config::{self, NoDebugInfo};
46 use rustc_incremental::IncrementalHashesMap;
47 use session::{self, DataTypeKind, Session};
49 use mir::lvalue::LvalueRef;
53 use common::{C_bool, C_bytes_in_context, C_i32, C_uint};
54 use collector::{self, TransItemCollectionMode};
55 use common::{C_struct_in_context, C_u64, C_undef};
56 use common::CrateContext;
57 use common::{fulfill_obligation};
58 use common::{type_is_zero_size, val_ty};
61 use context::{SharedCrateContext, CrateContextList};
65 use machine::llsize_of;
68 use monomorphize::{self, Instance};
69 use partitioning::{self, PartitioningStrategy, CodegenUnit};
70 use symbol_map::SymbolMap;
71 use symbol_names_test;
72 use trans_item::{TransItem, DefPathBasedNames};
76 use util::nodemap::{NodeSet, FxHashMap, FxHashSet};
79 use std::ffi::{CStr, CString};
83 use syntax_pos::{Span, DUMMY_SP};
86 use rustc::ty::layout::{self, Layout};
89 use mir::lvalue::Alignment;
91 pub struct StatRecorder<'a, 'tcx: 'a> {
92 ccx: &'a CrateContext<'a, 'tcx>,
97 impl<'a, 'tcx> StatRecorder<'a, 'tcx> {
98 pub fn new(ccx: &'a CrateContext<'a, 'tcx>, name: String) -> StatRecorder<'a, 'tcx> {
99 let istart = ccx.stats().n_llvm_insns.get();
108 impl<'a, 'tcx> Drop for StatRecorder<'a, 'tcx> {
110 if self.ccx.sess().trans_stats() {
111 let iend = self.ccx.stats().n_llvm_insns.get();
112 self.ccx.stats().fn_stats.borrow_mut()
113 .push((self.name.take().unwrap(), iend - self.istart));
114 self.ccx.stats().n_fns.set(self.ccx.stats().n_fns.get() + 1);
115 // Reset LLVM insn count to avoid compound costs.
116 self.ccx.stats().n_llvm_insns.set(self.istart);
121 pub fn get_meta(bcx: &Builder, fat_ptr: ValueRef) -> ValueRef {
122 bcx.struct_gep(fat_ptr, abi::FAT_PTR_EXTRA)
125 pub fn get_dataptr(bcx: &Builder, fat_ptr: ValueRef) -> ValueRef {
126 bcx.struct_gep(fat_ptr, abi::FAT_PTR_ADDR)
129 pub fn bin_op_to_icmp_predicate(op: hir::BinOp_,
131 -> llvm::IntPredicate {
133 hir::BiEq => llvm::IntEQ,
134 hir::BiNe => llvm::IntNE,
135 hir::BiLt => if signed { llvm::IntSLT } else { llvm::IntULT },
136 hir::BiLe => if signed { llvm::IntSLE } else { llvm::IntULE },
137 hir::BiGt => if signed { llvm::IntSGT } else { llvm::IntUGT },
138 hir::BiGe => if signed { llvm::IntSGE } else { llvm::IntUGE },
140 bug!("comparison_op_to_icmp_predicate: expected comparison operator, \
147 pub fn bin_op_to_fcmp_predicate(op: hir::BinOp_) -> llvm::RealPredicate {
149 hir::BiEq => llvm::RealOEQ,
150 hir::BiNe => llvm::RealUNE,
151 hir::BiLt => llvm::RealOLT,
152 hir::BiLe => llvm::RealOLE,
153 hir::BiGt => llvm::RealOGT,
154 hir::BiGe => llvm::RealOGE,
156 bug!("comparison_op_to_fcmp_predicate: expected comparison operator, \
163 pub fn compare_simd_types<'a, 'tcx>(
164 bcx: &Builder<'a, 'tcx>,
171 let signed = match t.sty {
173 let cmp = bin_op_to_fcmp_predicate(op);
174 return bcx.sext(bcx.fcmp(cmp, lhs, rhs), ret_ty);
176 ty::TyUint(_) => false,
177 ty::TyInt(_) => true,
178 _ => bug!("compare_simd_types: invalid SIMD type"),
181 let cmp = bin_op_to_icmp_predicate(op, signed);
182 // LLVM outputs an `< size x i1 >`, so we need to perform a sign extension
183 // to get the correctly sized type. This will compile to a single instruction
184 // once the IR is converted to assembly if the SIMD instruction is supported
185 // by the target architecture.
186 bcx.sext(bcx.icmp(cmp, lhs, rhs), ret_ty)
189 /// Retrieve the information we are losing (making dynamic) in an unsizing
192 /// The `old_info` argument is a bit funny. It is intended for use
193 /// in an upcast, where the new vtable for an object will be drived
194 /// from the old one.
195 pub fn unsized_info<'ccx, 'tcx>(ccx: &CrateContext<'ccx, 'tcx>,
198 old_info: Option<ValueRef>)
200 let (source, target) = ccx.tcx().struct_lockstep_tails(source, target);
201 match (&source.sty, &target.sty) {
202 (&ty::TyArray(_, len), &ty::TySlice(_)) => C_uint(ccx, len),
203 (&ty::TyDynamic(..), &ty::TyDynamic(..)) => {
204 // For now, upcasts are limited to changes in marker
205 // traits, and hence never actually require an actual
206 // change to the vtable.
207 old_info.expect("unsized_info: missing old info for trait upcast")
209 (_, &ty::TyDynamic(ref data, ..)) => {
210 consts::ptrcast(meth::get_vtable(ccx, source, data.principal()),
211 Type::vtable_ptr(ccx))
213 _ => bug!("unsized_info: invalid unsizing {:?} -> {:?}",
219 /// Coerce `src` to `dst_ty`. `src_ty` must be a thin pointer.
220 pub fn unsize_thin_ptr<'a, 'tcx>(
221 bcx: &Builder<'a, 'tcx>,
225 ) -> (ValueRef, ValueRef) {
226 debug!("unsize_thin_ptr: {:?} => {:?}", src_ty, dst_ty);
227 match (&src_ty.sty, &dst_ty.sty) {
228 (&ty::TyRef(_, ty::TypeAndMut { ty: a, .. }),
229 &ty::TyRef(_, ty::TypeAndMut { ty: b, .. })) |
230 (&ty::TyRef(_, ty::TypeAndMut { ty: a, .. }),
231 &ty::TyRawPtr(ty::TypeAndMut { ty: b, .. })) |
232 (&ty::TyRawPtr(ty::TypeAndMut { ty: a, .. }),
233 &ty::TyRawPtr(ty::TypeAndMut { ty: b, .. })) => {
234 assert!(bcx.ccx.shared().type_is_sized(a));
235 let ptr_ty = type_of::in_memory_type_of(bcx.ccx, b).ptr_to();
236 (bcx.pointercast(src, ptr_ty), unsized_info(bcx.ccx, a, b, None))
238 (&ty::TyAdt(def_a, _), &ty::TyAdt(def_b, _)) if def_a.is_box() && def_b.is_box() => {
239 let (a, b) = (src_ty.boxed_ty(), dst_ty.boxed_ty());
240 assert!(bcx.ccx.shared().type_is_sized(a));
241 let ptr_ty = type_of::in_memory_type_of(bcx.ccx, b).ptr_to();
242 (bcx.pointercast(src, ptr_ty), unsized_info(bcx.ccx, a, b, None))
244 _ => bug!("unsize_thin_ptr: called on bad types"),
248 /// Coerce `src`, which is a reference to a value of type `src_ty`,
249 /// to a value of type `dst_ty` and store the result in `dst`
250 pub fn coerce_unsized_into<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
251 src: &LvalueRef<'tcx>,
252 dst: &LvalueRef<'tcx>) {
253 let src_ty = src.ty.to_ty(bcx.tcx());
254 let dst_ty = dst.ty.to_ty(bcx.tcx());
255 let coerce_ptr = || {
256 let (base, info) = if common::type_is_fat_ptr(bcx.ccx, src_ty) {
257 // fat-ptr to fat-ptr unsize preserves the vtable
258 // i.e. &'a fmt::Debug+Send => &'a fmt::Debug
259 // So we need to pointercast the base to ensure
260 // the types match up.
261 let (base, info) = load_fat_ptr(bcx, src.llval, src.alignment, src_ty);
262 let llcast_ty = type_of::fat_ptr_base_ty(bcx.ccx, dst_ty);
263 let base = bcx.pointercast(base, llcast_ty);
266 let base = load_ty(bcx, src.llval, src.alignment, src_ty);
267 unsize_thin_ptr(bcx, base, src_ty, dst_ty)
269 store_fat_ptr(bcx, base, info, dst.llval, dst.alignment, dst_ty);
271 match (&src_ty.sty, &dst_ty.sty) {
272 (&ty::TyRef(..), &ty::TyRef(..)) |
273 (&ty::TyRef(..), &ty::TyRawPtr(..)) |
274 (&ty::TyRawPtr(..), &ty::TyRawPtr(..)) => {
277 (&ty::TyAdt(def_a, _), &ty::TyAdt(def_b, _)) if def_a.is_box() && def_b.is_box() => {
281 (&ty::TyAdt(def_a, substs_a), &ty::TyAdt(def_b, substs_b)) => {
282 assert_eq!(def_a, def_b);
284 let src_fields = def_a.variants[0].fields.iter().map(|f| {
285 monomorphize::field_ty(bcx.tcx(), substs_a, f)
287 let dst_fields = def_b.variants[0].fields.iter().map(|f| {
288 monomorphize::field_ty(bcx.tcx(), substs_b, f)
291 let iter = src_fields.zip(dst_fields).enumerate();
292 for (i, (src_fty, dst_fty)) in iter {
293 if type_is_zero_size(bcx.ccx, dst_fty) {
297 let (src_f, src_f_align) = src.trans_field_ptr(bcx, i);
298 let (dst_f, dst_f_align) = dst.trans_field_ptr(bcx, i);
299 if src_fty == dst_fty {
300 memcpy_ty(bcx, dst_f, src_f, src_fty, None);
304 &LvalueRef::new_sized_ty(src_f, src_fty, src_f_align),
305 &LvalueRef::new_sized_ty(dst_f, dst_fty, dst_f_align)
310 _ => bug!("coerce_unsized_into: invalid coercion {:?} -> {:?}",
316 pub fn custom_coerce_unsize_info<'scx, 'tcx>(scx: &SharedCrateContext<'scx, 'tcx>,
319 -> CustomCoerceUnsized {
320 let trait_ref = ty::Binder(ty::TraitRef {
321 def_id: scx.tcx().lang_items.coerce_unsized_trait().unwrap(),
322 substs: scx.tcx().mk_substs_trait(source_ty, &[target_ty])
325 match fulfill_obligation(scx, DUMMY_SP, trait_ref) {
326 traits::VtableImpl(traits::VtableImplData { impl_def_id, .. }) => {
327 scx.tcx().custom_coerce_unsized_kind(impl_def_id)
330 bug!("invalid CoerceUnsized vtable: {:?}", vtable);
335 pub fn cast_shift_expr_rhs(
336 cx: &Builder, op: hir::BinOp_, lhs: ValueRef, rhs: ValueRef
338 cast_shift_rhs(op, lhs, rhs, |a, b| cx.trunc(a, b), |a, b| cx.zext(a, b))
341 pub fn cast_shift_const_rhs(op: hir::BinOp_, lhs: ValueRef, rhs: ValueRef) -> ValueRef {
345 |a, b| unsafe { llvm::LLVMConstTrunc(a, b.to_ref()) },
346 |a, b| unsafe { llvm::LLVMConstZExt(a, b.to_ref()) })
349 fn cast_shift_rhs<F, G>(op: hir::BinOp_,
355 where F: FnOnce(ValueRef, Type) -> ValueRef,
356 G: FnOnce(ValueRef, Type) -> ValueRef
358 // Shifts may have any size int on the rhs
360 let mut rhs_llty = val_ty(rhs);
361 let mut lhs_llty = val_ty(lhs);
362 if rhs_llty.kind() == Vector {
363 rhs_llty = rhs_llty.element_type()
365 if lhs_llty.kind() == Vector {
366 lhs_llty = lhs_llty.element_type()
368 let rhs_sz = rhs_llty.int_width();
369 let lhs_sz = lhs_llty.int_width();
372 } else if lhs_sz > rhs_sz {
373 // FIXME (#1877: If shifting by negative
374 // values becomes not undefined then this is wrong.
384 /// Returns whether this session's target will use SEH-based unwinding.
386 /// This is only true for MSVC targets, and even then the 64-bit MSVC target
387 /// currently uses SEH-ish unwinding with DWARF info tables to the side (same as
388 /// 64-bit MinGW) instead of "full SEH".
389 pub fn wants_msvc_seh(sess: &Session) -> bool {
390 sess.target.target.options.is_like_msvc
393 pub fn call_assume<'a, 'tcx>(b: &Builder<'a, 'tcx>, val: ValueRef) {
394 let assume_intrinsic = b.ccx.get_intrinsic("llvm.assume");
395 b.call(assume_intrinsic, &[val], None);
398 /// Helper for loading values from memory. Does the necessary conversion if the in-memory type
399 /// differs from the type used for SSA values. Also handles various special cases where the type
400 /// gives us better information about what we are loading.
401 pub fn load_ty<'a, 'tcx>(b: &Builder<'a, 'tcx>, ptr: ValueRef,
402 alignment: Alignment, t: Ty<'tcx>) -> ValueRef {
404 if type_is_zero_size(ccx, t) {
405 return C_undef(type_of::type_of(ccx, t));
409 let global = llvm::LLVMIsAGlobalVariable(ptr);
410 if !global.is_null() && llvm::LLVMIsGlobalConstant(global) == llvm::True {
411 let val = llvm::LLVMGetInitializer(global);
414 return llvm::LLVMConstTrunc(val, Type::i1(ccx).to_ref());
422 b.trunc(b.load_range_assert(ptr, 0, 2, llvm::False, alignment.to_align()),
424 } else if t.is_char() {
425 // a char is a Unicode codepoint, and so takes values from 0
426 // to 0x10FFFF inclusive only.
427 b.load_range_assert(ptr, 0, 0x10FFFF + 1, llvm::False, alignment.to_align())
428 } else if (t.is_region_ptr() || t.is_box()) && !common::type_is_fat_ptr(ccx, t) {
429 b.load_nonnull(ptr, alignment.to_align())
431 b.load(ptr, alignment.to_align())
435 /// Helper for storing values in memory. Does the necessary conversion if the in-memory type
436 /// differs from the type used for SSA values.
437 pub fn store_ty<'a, 'tcx>(cx: &Builder<'a, 'tcx>, v: ValueRef, dst: ValueRef,
438 dst_align: Alignment, t: Ty<'tcx>) {
439 debug!("store_ty: {:?} : {:?} <- {:?}", Value(dst), t, Value(v));
441 if common::type_is_fat_ptr(cx.ccx, t) {
442 let lladdr = cx.extract_value(v, abi::FAT_PTR_ADDR);
443 let llextra = cx.extract_value(v, abi::FAT_PTR_EXTRA);
444 store_fat_ptr(cx, lladdr, llextra, dst, dst_align, t);
446 cx.store(from_immediate(cx, v), dst, dst_align.to_align());
450 pub fn store_fat_ptr<'a, 'tcx>(cx: &Builder<'a, 'tcx>,
454 dst_align: Alignment,
456 // FIXME: emit metadata
457 cx.store(data, get_dataptr(cx, dst), dst_align.to_align());
458 cx.store(extra, get_meta(cx, dst), dst_align.to_align());
461 pub fn load_fat_ptr<'a, 'tcx>(
462 b: &Builder<'a, 'tcx>, src: ValueRef, alignment: Alignment, t: Ty<'tcx>
463 ) -> (ValueRef, ValueRef) {
464 let ptr = get_dataptr(b, src);
465 let ptr = if t.is_region_ptr() || t.is_box() {
466 b.load_nonnull(ptr, alignment.to_align())
468 b.load(ptr, alignment.to_align())
471 let meta = get_meta(b, src);
472 let meta_ty = val_ty(meta);
473 // If the 'meta' field is a pointer, it's a vtable, so use load_nonnull
475 let meta = if meta_ty.element_type().kind() == llvm::TypeKind::Pointer {
476 b.load_nonnull(meta, None)
484 pub fn from_immediate(bcx: &Builder, val: ValueRef) -> ValueRef {
485 if val_ty(val) == Type::i1(bcx.ccx) {
486 bcx.zext(val, Type::i8(bcx.ccx))
492 pub fn to_immediate(bcx: &Builder, val: ValueRef, ty: Ty) -> ValueRef {
494 bcx.trunc(val, Type::i1(bcx.ccx))
500 pub enum Lifetime { Start, End }
503 // If LLVM lifetime intrinsic support is enabled (i.e. optimizations
504 // on), and `ptr` is nonzero-sized, then extracts the size of `ptr`
505 // and the intrinsic for `lt` and passes them to `emit`, which is in
506 // charge of generating code to call the passed intrinsic on whatever
507 // block of generated code is targetted for the intrinsic.
509 // If LLVM lifetime intrinsic support is disabled (i.e. optimizations
510 // off) or `ptr` is zero-sized, then no-op (does not call `emit`).
511 pub fn call(self, b: &Builder, ptr: ValueRef) {
512 if b.ccx.sess().opts.optimize == config::OptLevel::No {
516 let size = machine::llsize_of_alloc(b.ccx, val_ty(ptr).element_type());
521 let lifetime_intrinsic = b.ccx.get_intrinsic(match self {
522 Lifetime::Start => "llvm.lifetime.start",
523 Lifetime::End => "llvm.lifetime.end"
526 let ptr = b.pointercast(ptr, Type::i8p(b.ccx));
527 b.call(lifetime_intrinsic, &[C_u64(b.ccx, size), ptr], None);
531 pub fn call_memcpy<'a, 'tcx>(b: &Builder<'a, 'tcx>,
537 let ptr_width = &ccx.sess().target.target.target_pointer_width[..];
538 let key = format!("llvm.memcpy.p0i8.p0i8.i{}", ptr_width);
539 let memcpy = ccx.get_intrinsic(&key);
540 let src_ptr = b.pointercast(src, Type::i8p(ccx));
541 let dst_ptr = b.pointercast(dst, Type::i8p(ccx));
542 let size = b.intcast(n_bytes, ccx.int_type(), false);
543 let align = C_i32(ccx, align as i32);
544 let volatile = C_bool(ccx, false);
545 b.call(memcpy, &[dst_ptr, src_ptr, size, align, volatile], None);
548 pub fn memcpy_ty<'a, 'tcx>(
549 bcx: &Builder<'a, 'tcx>,
557 if type_is_zero_size(ccx, t) {
561 let llty = type_of::type_of(ccx, t);
562 let llsz = llsize_of(ccx, llty);
563 let llalign = align.unwrap_or_else(|| type_of::align_of(ccx, t));
564 call_memcpy(bcx, dst, src, llsz, llalign as u32);
567 pub fn call_memset<'a, 'tcx>(b: &Builder<'a, 'tcx>,
572 volatile: bool) -> ValueRef {
573 let ptr_width = &b.ccx.sess().target.target.target_pointer_width[..];
574 let intrinsic_key = format!("llvm.memset.p0i8.i{}", ptr_width);
575 let llintrinsicfn = b.ccx.get_intrinsic(&intrinsic_key);
576 let volatile = C_bool(b.ccx, volatile);
577 b.call(llintrinsicfn, &[ptr, fill_byte, size, align, volatile], None)
580 pub fn trans_instance<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, instance: Instance<'tcx>) {
581 let _s = if ccx.sess().trans_stats() {
582 let mut instance_name = String::new();
583 DefPathBasedNames::new(ccx.tcx(), true, true)
584 .push_def_path(instance.def_id(), &mut instance_name);
585 Some(StatRecorder::new(ccx, instance_name))
590 // this is an info! to allow collecting monomorphization statistics
591 // and to allow finding the last function before LLVM aborts from
593 info!("trans_instance({})", instance);
595 let fn_ty = common::instance_ty(ccx.shared(), &instance);
596 let sig = common::ty_fn_sig(ccx, fn_ty);
597 let sig = ccx.tcx().erase_late_bound_regions_and_normalize(&sig);
599 let lldecl = match ccx.instances().borrow().get(&instance) {
601 None => bug!("Instance `{:?}` not already declared", instance)
604 ccx.stats().n_closures.set(ccx.stats().n_closures.get() + 1);
606 if !ccx.sess().no_landing_pads() {
607 attributes::emit_uwtable(lldecl, true);
610 let mir = ccx.tcx().instance_mir(instance.def);
611 mir::trans_mir(ccx, lldecl, &mir, instance, sig);
614 pub fn llvm_linkage_by_name(name: &str) -> Option<Linkage> {
615 // Use the names from src/llvm/docs/LangRef.rst here. Most types are only
616 // applicable to variable declarations and may not really make sense for
617 // Rust code in the first place but whitelist them anyway and trust that
618 // the user knows what s/he's doing. Who knows, unanticipated use cases
619 // may pop up in the future.
621 // ghost, dllimport, dllexport and linkonce_odr_autohide are not supported
622 // and don't have to be, LLVM treats them as no-ops.
624 "appending" => Some(llvm::Linkage::AppendingLinkage),
625 "available_externally" => Some(llvm::Linkage::AvailableExternallyLinkage),
626 "common" => Some(llvm::Linkage::CommonLinkage),
627 "extern_weak" => Some(llvm::Linkage::ExternalWeakLinkage),
628 "external" => Some(llvm::Linkage::ExternalLinkage),
629 "internal" => Some(llvm::Linkage::InternalLinkage),
630 "linkonce" => Some(llvm::Linkage::LinkOnceAnyLinkage),
631 "linkonce_odr" => Some(llvm::Linkage::LinkOnceODRLinkage),
632 "private" => Some(llvm::Linkage::PrivateLinkage),
633 "weak" => Some(llvm::Linkage::WeakAnyLinkage),
634 "weak_odr" => Some(llvm::Linkage::WeakODRLinkage),
639 pub fn set_link_section(ccx: &CrateContext,
641 attrs: &[ast::Attribute]) {
642 if let Some(sect) = attr::first_attr_value_str_by_name(attrs, "link_section") {
643 if contains_null(§.as_str()) {
644 ccx.sess().fatal(&format!("Illegal null byte in link_section value: `{}`", §));
647 let buf = CString::new(sect.as_str().as_bytes()).unwrap();
648 llvm::LLVMSetSection(llval, buf.as_ptr());
653 /// Create the `main` function which will initialise the rust runtime and call
654 /// users main function.
655 pub fn maybe_create_entry_wrapper(ccx: &CrateContext) {
656 let (main_def_id, span) = match *ccx.sess().entry_fn.borrow() {
657 Some((id, span)) => {
658 (ccx.tcx().hir.local_def_id(id), span)
663 // check for the #[rustc_error] annotation, which forces an
664 // error in trans. This is used to write compile-fail tests
665 // that actually test that compilation succeeds without
666 // reporting an error.
667 if ccx.tcx().has_attr(main_def_id, "rustc_error") {
668 ccx.tcx().sess.span_fatal(span, "compilation successful");
671 let instance = Instance::mono(ccx.tcx(), main_def_id);
673 if !ccx.codegen_unit().contains_item(&TransItem::Fn(instance)) {
674 // We want to create the wrapper in the same codegen unit as Rust's main
679 let main_llfn = Callee::def(ccx, main_def_id, instance.substs).reify(ccx);
681 let et = ccx.sess().entry_type.get().unwrap();
683 config::EntryMain => create_entry_fn(ccx, span, main_llfn, true),
684 config::EntryStart => create_entry_fn(ccx, span, main_llfn, false),
685 config::EntryNone => {} // Do nothing.
688 fn create_entry_fn(ccx: &CrateContext,
691 use_start_lang_item: bool) {
692 let llfty = Type::func(&[ccx.int_type(), Type::i8p(ccx).ptr_to()], &ccx.int_type());
694 if declare::get_defined_value(ccx, "main").is_some() {
695 // FIXME: We should be smart and show a better diagnostic here.
696 ccx.sess().struct_span_err(sp, "entry symbol `main` defined multiple times")
697 .help("did you use #[no_mangle] on `fn main`? Use #[start] instead")
699 ccx.sess().abort_if_errors();
702 let llfn = declare::declare_cfn(ccx, "main", llfty);
704 // `main` should respect same config for frame pointer elimination as rest of code
705 attributes::set_frame_pointer_elimination(ccx, llfn);
707 let bld = Builder::new_block(ccx, llfn, "top");
709 debuginfo::gdb::insert_reference_to_gdb_debug_scripts_section_global(ccx, &bld);
711 let (start_fn, args) = if use_start_lang_item {
712 let start_def_id = ccx.tcx().require_lang_item(StartFnLangItem);
713 let empty_substs = ccx.tcx().intern_substs(&[]);
714 let start_fn = Callee::def(ccx, start_def_id, empty_substs).reify(ccx);
715 (start_fn, vec![bld.pointercast(rust_main, Type::i8p(ccx).ptr_to()), get_param(llfn, 0),
718 debug!("using user-defined start fn");
719 (rust_main, vec![get_param(llfn, 0 as c_uint), get_param(llfn, 1 as c_uint)])
722 let result = bld.call(start_fn, &args, None);
727 fn contains_null(s: &str) -> bool {
728 s.bytes().any(|b| b == 0)
731 fn write_metadata(cx: &SharedCrateContext,
732 exported_symbols: &NodeSet) -> Vec<u8> {
735 #[derive(PartialEq, Eq, PartialOrd, Ord)]
742 let kind = cx.sess().crate_types.borrow().iter().map(|ty| {
744 config::CrateTypeExecutable |
745 config::CrateTypeStaticlib |
746 config::CrateTypeCdylib => MetadataKind::None,
748 config::CrateTypeRlib => MetadataKind::Uncompressed,
750 config::CrateTypeDylib |
751 config::CrateTypeProcMacro => MetadataKind::Compressed,
755 if kind == MetadataKind::None {
759 let cstore = &cx.tcx().sess.cstore;
760 let metadata = cstore.encode_metadata(cx.tcx(),
764 if kind == MetadataKind::Uncompressed {
768 assert!(kind == MetadataKind::Compressed);
769 let mut compressed = cstore.metadata_encoding_version().to_vec();
770 compressed.extend_from_slice(&flate::deflate_bytes(&metadata));
772 let llmeta = C_bytes_in_context(cx.metadata_llcx(), &compressed[..]);
773 let llconst = C_struct_in_context(cx.metadata_llcx(), &[llmeta], false);
774 let name = cx.metadata_symbol_name();
775 let buf = CString::new(name).unwrap();
776 let llglobal = unsafe {
777 llvm::LLVMAddGlobal(cx.metadata_llmod(), val_ty(llconst).to_ref(), buf.as_ptr())
780 llvm::LLVMSetInitializer(llglobal, llconst);
782 cx.tcx().sess.cstore.metadata_section_name(&cx.sess().target.target);
783 let name = CString::new(section_name).unwrap();
784 llvm::LLVMSetSection(llglobal, name.as_ptr());
786 // Also generate a .section directive to force no
787 // flags, at least for ELF outputs, so that the
788 // metadata doesn't get loaded into memory.
789 let directive = format!(".section {}", section_name);
790 let directive = CString::new(directive).unwrap();
791 llvm::LLVMSetModuleInlineAsm(cx.metadata_llmod(), directive.as_ptr())
796 /// Find any symbols that are defined in one compilation unit, but not declared
797 /// in any other compilation unit. Give these symbols internal linkage.
798 fn internalize_symbols<'a, 'tcx>(sess: &Session,
799 ccxs: &CrateContextList<'a, 'tcx>,
800 symbol_map: &SymbolMap<'tcx>,
801 exported_symbols: &ExportedSymbols) {
802 let export_threshold =
803 symbol_export::crates_export_threshold(&sess.crate_types.borrow()[..]);
805 let exported_symbols = exported_symbols
806 .exported_symbols(LOCAL_CRATE)
808 .filter(|&&(_, export_level)| {
809 symbol_export::is_below_threshold(export_level, export_threshold)
811 .map(|&(ref name, _)| &name[..])
812 .collect::<FxHashSet<&str>>();
814 let scx = ccxs.shared();
817 let incr_comp = sess.opts.debugging_opts.incremental.is_some();
819 // 'unsafe' because we are holding on to CStr's from the LLVM module within
822 let mut referenced_somewhere = FxHashSet();
824 // Collect all symbols that need to stay externally visible because they
825 // are referenced via a declaration in some other codegen unit. In
826 // incremental compilation, we don't need to collect. See below for more
829 for ccx in ccxs.iter_need_trans() {
830 for val in iter_globals(ccx.llmod()).chain(iter_functions(ccx.llmod())) {
831 let linkage = llvm::LLVMRustGetLinkage(val);
832 // We only care about external declarations (not definitions)
833 // and available_externally definitions.
834 let is_available_externally =
835 linkage == llvm::Linkage::AvailableExternallyLinkage;
836 let is_decl = llvm::LLVMIsDeclaration(val) == llvm::True;
838 if is_decl || is_available_externally {
839 let symbol_name = CStr::from_ptr(llvm::LLVMGetValueName(val));
840 referenced_somewhere.insert(symbol_name);
846 // Also collect all symbols for which we cannot adjust linkage, because
847 // it is fixed by some directive in the source code.
848 let (locally_defined_symbols, linkage_fixed_explicitly) = {
849 let mut locally_defined_symbols = FxHashSet();
850 let mut linkage_fixed_explicitly = FxHashSet();
852 for trans_item in scx.translation_items().borrow().iter() {
853 let symbol_name = symbol_map.get_or_compute(scx, *trans_item);
854 if trans_item.explicit_linkage(tcx).is_some() {
855 linkage_fixed_explicitly.insert(symbol_name.clone());
857 locally_defined_symbols.insert(symbol_name);
860 (locally_defined_symbols, linkage_fixed_explicitly)
863 // Examine each external definition. If the definition is not used in
864 // any other compilation unit, and is not reachable from other crates,
865 // then give it internal linkage.
866 for ccx in ccxs.iter_need_trans() {
867 for val in iter_globals(ccx.llmod()).chain(iter_functions(ccx.llmod())) {
868 let linkage = llvm::LLVMRustGetLinkage(val);
870 let is_externally_visible = (linkage == llvm::Linkage::ExternalLinkage) ||
871 (linkage == llvm::Linkage::LinkOnceODRLinkage) ||
872 (linkage == llvm::Linkage::WeakODRLinkage);
874 if !is_externally_visible {
875 // This symbol is not visible outside of its codegen unit,
876 // so there is nothing to do for it.
880 let name_cstr = CStr::from_ptr(llvm::LLVMGetValueName(val));
881 let name_str = name_cstr.to_str().unwrap();
883 if exported_symbols.contains(&name_str) {
884 // This symbol is explicitly exported, so we can't
885 // mark it as internal or hidden.
889 let is_declaration = llvm::LLVMIsDeclaration(val) == llvm::True;
892 if locally_defined_symbols.contains(name_str) {
893 // Only mark declarations from the current crate as hidden.
894 // Otherwise we would mark things as hidden that are
895 // imported from other crates or native libraries.
896 llvm::LLVMRustSetVisibility(val, llvm::Visibility::Hidden);
899 let has_fixed_linkage = linkage_fixed_explicitly.contains(name_str);
901 if !has_fixed_linkage {
902 // In incremental compilation mode, we can't be sure that
903 // we saw all references because we don't know what's in
904 // cached compilation units, so we always assume that the
905 // given item has been referenced.
906 if incr_comp || referenced_somewhere.contains(&name_cstr) {
907 llvm::LLVMRustSetVisibility(val, llvm::Visibility::Hidden);
909 llvm::LLVMRustSetLinkage(val, llvm::Linkage::InternalLinkage);
912 llvm::LLVMSetDLLStorageClass(val, llvm::DLLStorageClass::Default);
913 llvm::UnsetComdat(val);
921 // Create a `__imp_<symbol> = &symbol` global for every public static `symbol`.
922 // This is required to satisfy `dllimport` references to static data in .rlibs
923 // when using MSVC linker. We do this only for data, as linker can fix up
924 // code references on its own.
925 // See #26591, #27438
926 fn create_imps(cx: &CrateContextList) {
927 // The x86 ABI seems to require that leading underscores are added to symbol
928 // names, so we need an extra underscore on 32-bit. There's also a leading
929 // '\x01' here which disables LLVM's symbol mangling (e.g. no extra
930 // underscores added in front).
931 let prefix = if cx.shared().sess().target.target.target_pointer_width == "32" {
937 for ccx in cx.iter_need_trans() {
938 let exported: Vec<_> = iter_globals(ccx.llmod())
940 llvm::LLVMRustGetLinkage(val) ==
941 llvm::Linkage::ExternalLinkage &&
942 llvm::LLVMIsDeclaration(val) == 0
946 let i8p_ty = Type::i8p(&ccx);
947 for val in exported {
948 let name = CStr::from_ptr(llvm::LLVMGetValueName(val));
949 let mut imp_name = prefix.as_bytes().to_vec();
950 imp_name.extend(name.to_bytes());
951 let imp_name = CString::new(imp_name).unwrap();
952 let imp = llvm::LLVMAddGlobal(ccx.llmod(),
954 imp_name.as_ptr() as *const _);
955 let init = llvm::LLVMConstBitCast(val, i8p_ty.to_ref());
956 llvm::LLVMSetInitializer(imp, init);
957 llvm::LLVMRustSetLinkage(imp, llvm::Linkage::ExternalLinkage);
965 step: unsafe extern "C" fn(ValueRef) -> ValueRef,
968 impl Iterator for ValueIter {
969 type Item = ValueRef;
971 fn next(&mut self) -> Option<ValueRef> {
974 self.cur = unsafe { (self.step)(old) };
982 fn iter_globals(llmod: llvm::ModuleRef) -> ValueIter {
985 cur: llvm::LLVMGetFirstGlobal(llmod),
986 step: llvm::LLVMGetNextGlobal,
991 fn iter_functions(llmod: llvm::ModuleRef) -> ValueIter {
994 cur: llvm::LLVMGetFirstFunction(llmod),
995 step: llvm::LLVMGetNextFunction,
1000 /// The context provided lists a set of reachable ids as calculated by
1001 /// middle::reachable, but this contains far more ids and symbols than we're
1002 /// actually exposing from the object file. This function will filter the set in
1003 /// the context to the set of ids which correspond to symbols that are exposed
1004 /// from the object file being generated.
1006 /// This list is later used by linkers to determine the set of symbols needed to
1007 /// be exposed from a dynamic library and it's also encoded into the metadata.
1008 pub fn find_exported_symbols(tcx: TyCtxt, reachable: NodeSet) -> NodeSet {
1009 reachable.into_iter().filter(|&id| {
1010 // Next, we want to ignore some FFI functions that are not exposed from
1011 // this crate. Reachable FFI functions can be lumped into two
1014 // 1. Those that are included statically via a static library
1015 // 2. Those included otherwise (e.g. dynamically or via a framework)
1017 // Although our LLVM module is not literally emitting code for the
1018 // statically included symbols, it's an export of our library which
1019 // needs to be passed on to the linker and encoded in the metadata.
1021 // As a result, if this id is an FFI item (foreign item) then we only
1022 // let it through if it's included statically.
1023 match tcx.hir.get(id) {
1024 hir_map::NodeForeignItem(..) => {
1025 let def_id = tcx.hir.local_def_id(id);
1026 tcx.sess.cstore.is_statically_included_foreign_item(def_id)
1029 // Only consider nodes that actually have exported symbols.
1030 hir_map::NodeItem(&hir::Item {
1031 node: hir::ItemStatic(..), .. }) |
1032 hir_map::NodeItem(&hir::Item {
1033 node: hir::ItemFn(..), .. }) |
1034 hir_map::NodeImplItem(&hir::ImplItem {
1035 node: hir::ImplItemKind::Method(..), .. }) => {
1036 let def_id = tcx.hir.local_def_id(id);
1037 let generics = tcx.item_generics(def_id);
1038 let attributes = tcx.get_attrs(def_id);
1039 (generics.parent_types == 0 && generics.types.is_empty()) &&
1040 // Functions marked with #[inline] are only ever translated
1041 // with "internal" linkage and are never exported.
1042 !attr::requests_inline(&attributes[..])
1050 pub fn trans_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
1051 analysis: ty::CrateAnalysis,
1052 incremental_hashes_map: &IncrementalHashesMap)
1053 -> CrateTranslation {
1054 let _task = tcx.dep_graph.in_task(DepNode::TransCrate);
1056 // Be careful with this krate: obviously it gives access to the
1057 // entire contents of the krate. So if you push any subtasks of
1058 // `TransCrate`, you need to be careful to register "reads" of the
1059 // particular items that will be processed.
1060 let krate = tcx.hir.krate();
1062 let ty::CrateAnalysis { export_map, reachable, name, .. } = analysis;
1063 let exported_symbols = find_exported_symbols(tcx, reachable);
1065 let check_overflow = tcx.sess.overflow_checks();
1067 let link_meta = link::build_link_meta(incremental_hashes_map, &name);
1069 let shared_ccx = SharedCrateContext::new(tcx,
1074 // Translate the metadata.
1075 let metadata = time(tcx.sess.time_passes(), "write metadata", || {
1076 write_metadata(&shared_ccx, shared_ccx.exported_symbols())
1079 let metadata_module = ModuleTranslation {
1080 name: link::METADATA_MODULE_NAME.to_string(),
1081 symbol_name_hash: 0, // we always rebuild metadata, at least for now
1082 source: ModuleSource::Translated(ModuleLlvm {
1083 llcx: shared_ccx.metadata_llcx(),
1084 llmod: shared_ccx.metadata_llmod(),
1087 let no_builtins = attr::contains_name(&krate.attrs, "no_builtins");
1089 // Skip crate items and just output metadata in -Z no-trans mode.
1090 if tcx.sess.opts.debugging_opts.no_trans ||
1091 !tcx.sess.opts.output_types.should_trans() {
1092 let empty_exported_symbols = ExportedSymbols::empty();
1093 let linker_info = LinkerInfo::new(&shared_ccx, &empty_exported_symbols);
1094 return CrateTranslation {
1096 metadata_module: metadata_module,
1099 exported_symbols: empty_exported_symbols,
1100 no_builtins: no_builtins,
1101 linker_info: linker_info,
1102 windows_subsystem: None,
1106 // Run the translation item collector and partition the collected items into
1108 let (codegen_units, symbol_map) = collect_and_partition_translation_items(&shared_ccx);
1110 let symbol_map = Rc::new(symbol_map);
1112 let previous_work_products = trans_reuse_previous_work_products(&shared_ccx,
1116 let crate_context_list = CrateContextList::new(&shared_ccx,
1118 previous_work_products,
1119 symbol_map.clone());
1120 let modules: Vec<_> = crate_context_list.iter_all()
1122 let source = match ccx.previous_work_product() {
1123 Some(buf) => ModuleSource::Preexisting(buf.clone()),
1124 None => ModuleSource::Translated(ModuleLlvm {
1131 name: String::from(ccx.codegen_unit().name()),
1132 symbol_name_hash: ccx.codegen_unit()
1133 .compute_symbol_name_hash(&shared_ccx,
1140 assert_module_sources::assert_module_sources(tcx, &modules);
1142 // Instantiate translation items without filling out definitions yet...
1143 for ccx in crate_context_list.iter_need_trans() {
1144 let dep_node = ccx.codegen_unit().work_product_dep_node();
1145 tcx.dep_graph.with_task(dep_node,
1147 AssertDepGraphSafe(symbol_map.clone()),
1150 fn trans_decl_task<'a, 'tcx>(ccx: CrateContext<'a, 'tcx>,
1151 symbol_map: AssertDepGraphSafe<Rc<SymbolMap<'tcx>>>) {
1152 // FIXME(#40304): Instead of this, the symbol-map should be an
1153 // on-demand thing that we compute.
1154 let AssertDepGraphSafe(symbol_map) = symbol_map;
1155 let cgu = ccx.codegen_unit();
1156 let trans_items = cgu.items_in_deterministic_order(ccx.tcx(), &symbol_map);
1157 for (trans_item, linkage) in trans_items {
1158 trans_item.predefine(&ccx, linkage);
1163 // ... and now that we have everything pre-defined, fill out those definitions.
1164 for ccx in crate_context_list.iter_need_trans() {
1165 let dep_node = ccx.codegen_unit().work_product_dep_node();
1166 tcx.dep_graph.with_task(dep_node,
1168 AssertDepGraphSafe(symbol_map.clone()),
1171 fn trans_def_task<'a, 'tcx>(ccx: CrateContext<'a, 'tcx>,
1172 symbol_map: AssertDepGraphSafe<Rc<SymbolMap<'tcx>>>) {
1173 // FIXME(#40304): Instead of this, the symbol-map should be an
1174 // on-demand thing that we compute.
1175 let AssertDepGraphSafe(symbol_map) = symbol_map;
1176 let cgu = ccx.codegen_unit();
1177 let trans_items = cgu.items_in_deterministic_order(ccx.tcx(), &symbol_map);
1178 for (trans_item, _) in trans_items {
1179 trans_item.define(&ccx);
1182 // If this codegen unit contains the main function, also create the
1184 maybe_create_entry_wrapper(&ccx);
1186 // Run replace-all-uses-with for statics that need it
1187 for &(old_g, new_g) in ccx.statics_to_rauw().borrow().iter() {
1189 let bitcast = llvm::LLVMConstPointerCast(new_g, llvm::LLVMTypeOf(old_g));
1190 llvm::LLVMReplaceAllUsesWith(old_g, bitcast);
1191 llvm::LLVMDeleteGlobal(old_g);
1195 // Finalize debuginfo
1196 if ccx.sess().opts.debuginfo != NoDebugInfo {
1197 debuginfo::finalize(&ccx);
1202 symbol_names_test::report_symbol_names(&shared_ccx);
1204 if shared_ccx.sess().trans_stats() {
1205 let stats = shared_ccx.stats();
1206 println!("--- trans stats ---");
1207 println!("n_glues_created: {}", stats.n_glues_created.get());
1208 println!("n_null_glues: {}", stats.n_null_glues.get());
1209 println!("n_real_glues: {}", stats.n_real_glues.get());
1211 println!("n_fns: {}", stats.n_fns.get());
1212 println!("n_inlines: {}", stats.n_inlines.get());
1213 println!("n_closures: {}", stats.n_closures.get());
1214 println!("fn stats:");
1215 stats.fn_stats.borrow_mut().sort_by(|&(_, insns_a), &(_, insns_b)| {
1216 insns_b.cmp(&insns_a)
1218 for tuple in stats.fn_stats.borrow().iter() {
1220 (ref name, insns) => {
1221 println!("{} insns, {}", insns, *name);
1227 if shared_ccx.sess().count_llvm_insns() {
1228 for (k, v) in shared_ccx.stats().llvm_insns.borrow().iter() {
1229 println!("{:7} {}", *v, *k);
1233 let sess = shared_ccx.sess();
1235 let exported_symbols = ExportedSymbols::compute_from(&shared_ccx,
1238 // Now that we have all symbols that are exported from the CGUs of this
1239 // crate, we can run the `internalize_symbols` pass.
1240 time(shared_ccx.sess().time_passes(), "internalize symbols", || {
1241 internalize_symbols(sess,
1242 &crate_context_list,
1247 if tcx.sess.opts.debugging_opts.print_type_sizes {
1248 gather_type_sizes(tcx);
1251 if sess.target.target.options.is_like_msvc &&
1252 sess.crate_types.borrow().iter().any(|ct| *ct == config::CrateTypeRlib) {
1253 create_imps(&crate_context_list);
1256 let linker_info = LinkerInfo::new(&shared_ccx, &exported_symbols);
1258 let subsystem = attr::first_attr_value_str_by_name(&krate.attrs,
1259 "windows_subsystem");
1260 let windows_subsystem = subsystem.map(|subsystem| {
1261 if subsystem != "windows" && subsystem != "console" {
1262 tcx.sess.fatal(&format!("invalid windows subsystem `{}`, only \
1263 `windows` and `console` are allowed",
1266 subsystem.to_string()
1271 metadata_module: metadata_module,
1274 exported_symbols: exported_symbols,
1275 no_builtins: no_builtins,
1276 linker_info: linker_info,
1277 windows_subsystem: windows_subsystem,
1281 fn gather_type_sizes<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
1282 let layout_cache = tcx.layout_cache.borrow();
1283 for (ty, layout) in layout_cache.iter() {
1285 // (delay format until we actually need it)
1286 let record = |kind, opt_discr_size, variants| {
1287 let type_desc = format!("{:?}", ty);
1288 let overall_size = layout.size(&tcx.data_layout);
1289 let align = layout.align(&tcx.data_layout);
1290 tcx.sess.code_stats.borrow_mut().record_type_size(kind,
1298 let (adt_def, substs) = match ty.sty {
1299 ty::TyAdt(ref adt_def, substs) => {
1300 debug!("print-type-size t: `{:?}` process adt", ty);
1304 ty::TyClosure(..) => {
1305 debug!("print-type-size t: `{:?}` record closure", ty);
1306 record(DataTypeKind::Closure, None, vec![]);
1311 debug!("print-type-size t: `{:?}` skip non-nominal", ty);
1316 let adt_kind = adt_def.adt_kind();
1318 let build_field_info = |(field_name, field_ty): (ast::Name, Ty), offset: &layout::Size| {
1319 match layout_cache.get(&field_ty) {
1320 None => bug!("no layout found for field {} type: `{:?}`", field_name, field_ty),
1321 Some(field_layout) => {
1322 session::FieldInfo {
1323 name: field_name.to_string(),
1324 offset: offset.bytes(),
1325 size: field_layout.size(&tcx.data_layout).bytes(),
1326 align: field_layout.align(&tcx.data_layout).abi(),
1332 let build_primitive_info = |name: ast::Name, value: &layout::Primitive| {
1333 session::VariantInfo {
1334 name: Some(name.to_string()),
1335 kind: session::SizeKind::Exact,
1336 align: value.align(&tcx.data_layout).abi(),
1337 size: value.size(&tcx.data_layout).bytes(),
1343 WithDiscrim(&'a layout::Struct),
1344 NoDiscrim(&'a layout::Struct),
1347 let build_variant_info = |n: Option<ast::Name>, flds: &[(ast::Name, Ty)], layout: Fields| {
1348 let (s, field_offsets) = match layout {
1349 Fields::WithDiscrim(s) => (s, &s.offsets[1..]),
1350 Fields::NoDiscrim(s) => (s, &s.offsets[0..]),
1352 let field_info: Vec<_> = flds.iter()
1353 .zip(field_offsets.iter())
1354 .map(|(&field_name_ty, offset)| build_field_info(field_name_ty, offset))
1357 session::VariantInfo {
1358 name: n.map(|n|n.to_string()),
1360 session::SizeKind::Exact
1362 session::SizeKind::Min
1364 align: s.align.abi(),
1365 size: s.min_size.bytes(),
1371 Layout::StructWrappedNullablePointer { nonnull: ref variant_layout,
1374 discrfield_source: _ } => {
1375 debug!("print-type-size t: `{:?}` adt struct-wrapped nullable nndiscr {} is {:?}",
1376 ty, nndiscr, variant_layout);
1377 let variant_def = &adt_def.variants[nndiscr as usize];
1378 let fields: Vec<_> = variant_def.fields.iter()
1379 .map(|field_def| (field_def.name, field_def.ty(tcx, substs)))
1381 record(adt_kind.into(),
1383 vec![build_variant_info(Some(variant_def.name),
1385 Fields::NoDiscrim(variant_layout))]);
1387 Layout::RawNullablePointer { nndiscr, value } => {
1388 debug!("print-type-size t: `{:?}` adt raw nullable nndiscr {} is {:?}",
1389 ty, nndiscr, value);
1390 let variant_def = &adt_def.variants[nndiscr as usize];
1391 record(adt_kind.into(), None,
1392 vec![build_primitive_info(variant_def.name, &value)]);
1394 Layout::Univariant { variant: ref variant_layout, non_zero: _ } => {
1395 let variant_names = || {
1396 adt_def.variants.iter().map(|v|format!("{}", v.name)).collect::<Vec<_>>()
1398 debug!("print-type-size t: `{:?}` adt univariant {:?} variants: {:?}",
1399 ty, variant_layout, variant_names());
1400 assert!(adt_def.variants.len() <= 1,
1401 "univariant with variants {:?}", variant_names());
1402 if adt_def.variants.len() == 1 {
1403 let variant_def = &adt_def.variants[0];
1404 let fields: Vec<_> = variant_def.fields.iter()
1405 .map(|field_def| (field_def.name, field_def.ty(tcx, substs)))
1407 record(adt_kind.into(),
1409 vec![build_variant_info(Some(variant_def.name),
1411 Fields::NoDiscrim(variant_layout))]);
1413 // (This case arises for *empty* enums; so give it
1415 record(adt_kind.into(), None, vec![]);
1419 Layout::General { ref variants, discr, .. } => {
1420 debug!("print-type-size t: `{:?}` adt general variants def {} layouts {} {:?}",
1421 ty, adt_def.variants.len(), variants.len(), variants);
1422 let variant_infos: Vec<_> = adt_def.variants.iter()
1423 .zip(variants.iter())
1424 .map(|(variant_def, variant_layout)| {
1425 let fields: Vec<_> = variant_def.fields.iter()
1426 .map(|field_def| (field_def.name, field_def.ty(tcx, substs)))
1428 build_variant_info(Some(variant_def.name),
1430 Fields::WithDiscrim(variant_layout))
1433 record(adt_kind.into(), Some(discr.size()), variant_infos);
1436 Layout::UntaggedUnion { ref variants } => {
1437 debug!("print-type-size t: `{:?}` adt union variants {:?}",
1439 // layout does not currently store info about each
1441 record(adt_kind.into(), None, Vec::new());
1444 Layout::CEnum { discr, .. } => {
1445 debug!("print-type-size t: `{:?}` adt c-like enum", ty);
1446 let variant_infos: Vec<_> = adt_def.variants.iter()
1447 .map(|variant_def| {
1448 build_primitive_info(variant_def.name,
1449 &layout::Primitive::Int(discr))
1452 record(adt_kind.into(), Some(discr.size()), variant_infos);
1455 // other cases provide little interesting (i.e. adjustable
1456 // via representation tweaks) size info beyond total size.
1457 Layout::Scalar { .. } |
1458 Layout::Vector { .. } |
1459 Layout::Array { .. } |
1460 Layout::FatPointer { .. } => {
1461 debug!("print-type-size t: `{:?}` adt other", ty);
1462 record(adt_kind.into(), None, Vec::new())
1468 /// For each CGU, identify if we can reuse an existing object file (or
1469 /// maybe other context).
1470 fn trans_reuse_previous_work_products(scx: &SharedCrateContext,
1471 codegen_units: &[CodegenUnit],
1472 symbol_map: &SymbolMap)
1473 -> Vec<Option<WorkProduct>> {
1474 debug!("trans_reuse_previous_work_products()");
1478 let id = cgu.work_product_id();
1480 let hash = cgu.compute_symbol_name_hash(scx, symbol_map);
1482 debug!("trans_reuse_previous_work_products: id={:?} hash={}", id, hash);
1484 if let Some(work_product) = scx.dep_graph().previous_work_product(&id) {
1485 if work_product.input_hash == hash {
1486 debug!("trans_reuse_previous_work_products: reusing {:?}", work_product);
1487 return Some(work_product);
1489 if scx.sess().opts.debugging_opts.incremental_info {
1490 println!("incremental: CGU `{}` invalidated because of \
1491 changed partitioning hash.",
1494 debug!("trans_reuse_previous_work_products: \
1495 not reusing {:?} because hash changed to {:?}",
1496 work_product, hash);
1505 fn collect_and_partition_translation_items<'a, 'tcx>(scx: &SharedCrateContext<'a, 'tcx>)
1506 -> (Vec<CodegenUnit<'tcx>>, SymbolMap<'tcx>) {
1507 let time_passes = scx.sess().time_passes();
1509 let collection_mode = match scx.sess().opts.debugging_opts.print_trans_items {
1511 let mode_string = s.to_lowercase();
1512 let mode_string = mode_string.trim();
1513 if mode_string == "eager" {
1514 TransItemCollectionMode::Eager
1516 if mode_string != "lazy" {
1517 let message = format!("Unknown codegen-item collection mode '{}'. \
1518 Falling back to 'lazy' mode.",
1520 scx.sess().warn(&message);
1523 TransItemCollectionMode::Lazy
1526 None => TransItemCollectionMode::Lazy
1529 let (items, inlining_map) =
1530 time(time_passes, "translation item collection", || {
1531 collector::collect_crate_translation_items(&scx, collection_mode)
1534 let symbol_map = SymbolMap::build(scx, items.iter().cloned());
1536 let strategy = if scx.sess().opts.debugging_opts.incremental.is_some() {
1537 PartitioningStrategy::PerModule
1539 PartitioningStrategy::FixedUnitCount(scx.sess().opts.cg.codegen_units)
1542 let codegen_units = time(time_passes, "codegen unit partitioning", || {
1543 partitioning::partition(scx,
1544 items.iter().cloned(),
1549 assert!(scx.tcx().sess.opts.cg.codegen_units == codegen_units.len() ||
1550 scx.tcx().sess.opts.debugging_opts.incremental.is_some());
1553 let mut ccx_map = scx.translation_items().borrow_mut();
1555 for trans_item in items.iter().cloned() {
1556 ccx_map.insert(trans_item);
1560 if scx.sess().opts.debugging_opts.print_trans_items.is_some() {
1561 let mut item_to_cgus = FxHashMap();
1563 for cgu in &codegen_units {
1564 for (&trans_item, &linkage) in cgu.items() {
1565 item_to_cgus.entry(trans_item)
1566 .or_insert(Vec::new())
1567 .push((cgu.name().clone(), linkage));
1571 let mut item_keys: Vec<_> = items
1574 let mut output = i.to_string(scx.tcx());
1575 output.push_str(" @@");
1576 let mut empty = Vec::new();
1577 let mut cgus = item_to_cgus.get_mut(i).unwrap_or(&mut empty);
1578 cgus.as_mut_slice().sort_by_key(|&(ref name, _)| name.clone());
1580 for &(ref cgu_name, linkage) in cgus.iter() {
1581 output.push_str(" ");
1582 output.push_str(&cgu_name[..]);
1584 let linkage_abbrev = match linkage {
1585 llvm::Linkage::ExternalLinkage => "External",
1586 llvm::Linkage::AvailableExternallyLinkage => "Available",
1587 llvm::Linkage::LinkOnceAnyLinkage => "OnceAny",
1588 llvm::Linkage::LinkOnceODRLinkage => "OnceODR",
1589 llvm::Linkage::WeakAnyLinkage => "WeakAny",
1590 llvm::Linkage::WeakODRLinkage => "WeakODR",
1591 llvm::Linkage::AppendingLinkage => "Appending",
1592 llvm::Linkage::InternalLinkage => "Internal",
1593 llvm::Linkage::PrivateLinkage => "Private",
1594 llvm::Linkage::ExternalWeakLinkage => "ExternalWeak",
1595 llvm::Linkage::CommonLinkage => "Common",
1598 output.push_str("[");
1599 output.push_str(linkage_abbrev);
1600 output.push_str("]");
1608 for item in item_keys {
1609 println!("TRANS_ITEM {}", item);
1613 (codegen_units, symbol_map)