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::{ContextRef, Linkage, ModuleRef, ValueRef, Vector, get_param};
37 use rustc::hir::def_id::LOCAL_CRATE;
38 use middle::lang_items::StartFnLangItem;
39 use middle::cstore::EncodedMetadata;
40 use rustc::ty::{self, Ty, TyCtxt};
41 use rustc::dep_graph::AssertDepGraphSafe;
42 use rustc::middle::cstore::LinkMeta;
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, C_array};
56 use common::CrateContext;
57 use common::{type_is_zero_size, val_ty};
60 use context::{self, LocalCrateContext, SharedCrateContext, Stats};
66 use monomorphize::{self, Instance};
67 use partitioning::{self, PartitioningStrategy, CodegenUnit};
68 use symbol_map::SymbolMap;
69 use symbol_names_test;
70 use trans_item::{TransItem, DefPathBasedNames};
74 use util::nodemap::{NodeSet, FxHashMap, FxHashSet};
77 use std::ffi::{CStr, CString};
84 use rustc::ty::layout::{self, Layout};
87 use mir::lvalue::Alignment;
89 pub struct StatRecorder<'a, 'tcx: 'a> {
90 ccx: &'a CrateContext<'a, 'tcx>,
95 impl<'a, 'tcx> StatRecorder<'a, 'tcx> {
96 pub fn new(ccx: &'a CrateContext<'a, 'tcx>, name: String) -> StatRecorder<'a, 'tcx> {
97 let istart = ccx.stats().n_llvm_insns.get();
106 impl<'a, 'tcx> Drop for StatRecorder<'a, 'tcx> {
108 if self.ccx.sess().trans_stats() {
109 let iend = self.ccx.stats().n_llvm_insns.get();
110 self.ccx.stats().fn_stats.borrow_mut()
111 .push((self.name.take().unwrap(), iend - self.istart));
112 self.ccx.stats().n_fns.set(self.ccx.stats().n_fns.get() + 1);
113 // Reset LLVM insn count to avoid compound costs.
114 self.ccx.stats().n_llvm_insns.set(self.istart);
119 pub fn get_meta(bcx: &Builder, fat_ptr: ValueRef) -> ValueRef {
120 bcx.struct_gep(fat_ptr, abi::FAT_PTR_EXTRA)
123 pub fn get_dataptr(bcx: &Builder, fat_ptr: ValueRef) -> ValueRef {
124 bcx.struct_gep(fat_ptr, abi::FAT_PTR_ADDR)
127 pub fn bin_op_to_icmp_predicate(op: hir::BinOp_,
129 -> llvm::IntPredicate {
131 hir::BiEq => llvm::IntEQ,
132 hir::BiNe => llvm::IntNE,
133 hir::BiLt => if signed { llvm::IntSLT } else { llvm::IntULT },
134 hir::BiLe => if signed { llvm::IntSLE } else { llvm::IntULE },
135 hir::BiGt => if signed { llvm::IntSGT } else { llvm::IntUGT },
136 hir::BiGe => if signed { llvm::IntSGE } else { llvm::IntUGE },
138 bug!("comparison_op_to_icmp_predicate: expected comparison operator, \
145 pub fn bin_op_to_fcmp_predicate(op: hir::BinOp_) -> llvm::RealPredicate {
147 hir::BiEq => llvm::RealOEQ,
148 hir::BiNe => llvm::RealUNE,
149 hir::BiLt => llvm::RealOLT,
150 hir::BiLe => llvm::RealOLE,
151 hir::BiGt => llvm::RealOGT,
152 hir::BiGe => llvm::RealOGE,
154 bug!("comparison_op_to_fcmp_predicate: expected comparison operator, \
161 pub fn compare_simd_types<'a, 'tcx>(
162 bcx: &Builder<'a, 'tcx>,
169 let signed = match t.sty {
171 let cmp = bin_op_to_fcmp_predicate(op);
172 return bcx.sext(bcx.fcmp(cmp, lhs, rhs), ret_ty);
174 ty::TyUint(_) => false,
175 ty::TyInt(_) => true,
176 _ => bug!("compare_simd_types: invalid SIMD type"),
179 let cmp = bin_op_to_icmp_predicate(op, signed);
180 // LLVM outputs an `< size x i1 >`, so we need to perform a sign extension
181 // to get the correctly sized type. This will compile to a single instruction
182 // once the IR is converted to assembly if the SIMD instruction is supported
183 // by the target architecture.
184 bcx.sext(bcx.icmp(cmp, lhs, rhs), ret_ty)
187 /// Retrieve the information we are losing (making dynamic) in an unsizing
190 /// The `old_info` argument is a bit funny. It is intended for use
191 /// in an upcast, where the new vtable for an object will be drived
192 /// from the old one.
193 pub fn unsized_info<'ccx, 'tcx>(ccx: &CrateContext<'ccx, 'tcx>,
196 old_info: Option<ValueRef>)
198 let (source, target) = ccx.tcx().struct_lockstep_tails(source, target);
199 match (&source.sty, &target.sty) {
200 (&ty::TyArray(_, len), &ty::TySlice(_)) => C_uint(ccx, len),
201 (&ty::TyDynamic(..), &ty::TyDynamic(..)) => {
202 // For now, upcasts are limited to changes in marker
203 // traits, and hence never actually require an actual
204 // change to the vtable.
205 old_info.expect("unsized_info: missing old info for trait upcast")
207 (_, &ty::TyDynamic(ref data, ..)) => {
208 consts::ptrcast(meth::get_vtable(ccx, source, data.principal()),
209 Type::vtable_ptr(ccx))
211 _ => bug!("unsized_info: invalid unsizing {:?} -> {:?}",
217 /// Coerce `src` to `dst_ty`. `src_ty` must be a thin pointer.
218 pub fn unsize_thin_ptr<'a, 'tcx>(
219 bcx: &Builder<'a, 'tcx>,
223 ) -> (ValueRef, ValueRef) {
224 debug!("unsize_thin_ptr: {:?} => {:?}", src_ty, dst_ty);
225 match (&src_ty.sty, &dst_ty.sty) {
226 (&ty::TyRef(_, ty::TypeAndMut { ty: a, .. }),
227 &ty::TyRef(_, ty::TypeAndMut { ty: b, .. })) |
228 (&ty::TyRef(_, ty::TypeAndMut { ty: a, .. }),
229 &ty::TyRawPtr(ty::TypeAndMut { ty: b, .. })) |
230 (&ty::TyRawPtr(ty::TypeAndMut { ty: a, .. }),
231 &ty::TyRawPtr(ty::TypeAndMut { ty: b, .. })) => {
232 assert!(bcx.ccx.shared().type_is_sized(a));
233 let ptr_ty = type_of::in_memory_type_of(bcx.ccx, b).ptr_to();
234 (bcx.pointercast(src, ptr_ty), unsized_info(bcx.ccx, a, b, None))
236 (&ty::TyAdt(def_a, _), &ty::TyAdt(def_b, _)) if def_a.is_box() && def_b.is_box() => {
237 let (a, b) = (src_ty.boxed_ty(), dst_ty.boxed_ty());
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 _ => bug!("unsize_thin_ptr: called on bad types"),
246 /// Coerce `src`, which is a reference to a value of type `src_ty`,
247 /// to a value of type `dst_ty` and store the result in `dst`
248 pub fn coerce_unsized_into<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
249 src: &LvalueRef<'tcx>,
250 dst: &LvalueRef<'tcx>) {
251 let src_ty = src.ty.to_ty(bcx.tcx());
252 let dst_ty = dst.ty.to_ty(bcx.tcx());
253 let coerce_ptr = || {
254 let (base, info) = if common::type_is_fat_ptr(bcx.ccx, src_ty) {
255 // fat-ptr to fat-ptr unsize preserves the vtable
256 // i.e. &'a fmt::Debug+Send => &'a fmt::Debug
257 // So we need to pointercast the base to ensure
258 // the types match up.
259 let (base, info) = load_fat_ptr(bcx, src.llval, src.alignment, src_ty);
260 let llcast_ty = type_of::fat_ptr_base_ty(bcx.ccx, dst_ty);
261 let base = bcx.pointercast(base, llcast_ty);
264 let base = load_ty(bcx, src.llval, src.alignment, src_ty);
265 unsize_thin_ptr(bcx, base, src_ty, dst_ty)
267 store_fat_ptr(bcx, base, info, dst.llval, dst.alignment, dst_ty);
269 match (&src_ty.sty, &dst_ty.sty) {
270 (&ty::TyRef(..), &ty::TyRef(..)) |
271 (&ty::TyRef(..), &ty::TyRawPtr(..)) |
272 (&ty::TyRawPtr(..), &ty::TyRawPtr(..)) => {
275 (&ty::TyAdt(def_a, _), &ty::TyAdt(def_b, _)) if def_a.is_box() && def_b.is_box() => {
279 (&ty::TyAdt(def_a, substs_a), &ty::TyAdt(def_b, substs_b)) => {
280 assert_eq!(def_a, def_b);
282 let src_fields = def_a.variants[0].fields.iter().map(|f| {
283 monomorphize::field_ty(bcx.tcx(), substs_a, f)
285 let dst_fields = def_b.variants[0].fields.iter().map(|f| {
286 monomorphize::field_ty(bcx.tcx(), substs_b, f)
289 let iter = src_fields.zip(dst_fields).enumerate();
290 for (i, (src_fty, dst_fty)) in iter {
291 if type_is_zero_size(bcx.ccx, dst_fty) {
295 let (src_f, src_f_align) = src.trans_field_ptr(bcx, i);
296 let (dst_f, dst_f_align) = dst.trans_field_ptr(bcx, i);
297 if src_fty == dst_fty {
298 memcpy_ty(bcx, dst_f, src_f, src_fty, None);
302 &LvalueRef::new_sized_ty(src_f, src_fty, src_f_align),
303 &LvalueRef::new_sized_ty(dst_f, dst_fty, dst_f_align)
308 _ => bug!("coerce_unsized_into: invalid coercion {:?} -> {:?}",
314 pub fn cast_shift_expr_rhs(
315 cx: &Builder, op: hir::BinOp_, lhs: ValueRef, rhs: ValueRef
317 cast_shift_rhs(op, lhs, rhs, |a, b| cx.trunc(a, b), |a, b| cx.zext(a, b))
320 pub fn cast_shift_const_rhs(op: hir::BinOp_, lhs: ValueRef, rhs: ValueRef) -> ValueRef {
324 |a, b| unsafe { llvm::LLVMConstTrunc(a, b.to_ref()) },
325 |a, b| unsafe { llvm::LLVMConstZExt(a, b.to_ref()) })
328 fn cast_shift_rhs<F, G>(op: hir::BinOp_,
334 where F: FnOnce(ValueRef, Type) -> ValueRef,
335 G: FnOnce(ValueRef, Type) -> ValueRef
337 // Shifts may have any size int on the rhs
339 let mut rhs_llty = val_ty(rhs);
340 let mut lhs_llty = val_ty(lhs);
341 if rhs_llty.kind() == Vector {
342 rhs_llty = rhs_llty.element_type()
344 if lhs_llty.kind() == Vector {
345 lhs_llty = lhs_llty.element_type()
347 let rhs_sz = rhs_llty.int_width();
348 let lhs_sz = lhs_llty.int_width();
351 } else if lhs_sz > rhs_sz {
352 // FIXME (#1877: If shifting by negative
353 // values becomes not undefined then this is wrong.
363 /// Returns whether this session's target will use SEH-based unwinding.
365 /// This is only true for MSVC targets, and even then the 64-bit MSVC target
366 /// currently uses SEH-ish unwinding with DWARF info tables to the side (same as
367 /// 64-bit MinGW) instead of "full SEH".
368 pub fn wants_msvc_seh(sess: &Session) -> bool {
369 sess.target.target.options.is_like_msvc
372 pub fn call_assume<'a, 'tcx>(b: &Builder<'a, 'tcx>, val: ValueRef) {
373 let assume_intrinsic = b.ccx.get_intrinsic("llvm.assume");
374 b.call(assume_intrinsic, &[val], None);
377 /// Helper for loading values from memory. Does the necessary conversion if the in-memory type
378 /// differs from the type used for SSA values. Also handles various special cases where the type
379 /// gives us better information about what we are loading.
380 pub fn load_ty<'a, 'tcx>(b: &Builder<'a, 'tcx>, ptr: ValueRef,
381 alignment: Alignment, t: Ty<'tcx>) -> ValueRef {
383 if type_is_zero_size(ccx, t) {
384 return C_undef(type_of::type_of(ccx, t));
388 let global = llvm::LLVMIsAGlobalVariable(ptr);
389 if !global.is_null() && llvm::LLVMIsGlobalConstant(global) == llvm::True {
390 let val = llvm::LLVMGetInitializer(global);
393 return llvm::LLVMConstTrunc(val, Type::i1(ccx).to_ref());
401 b.trunc(b.load_range_assert(ptr, 0, 2, llvm::False, alignment.to_align()),
403 } else if t.is_char() {
404 // a char is a Unicode codepoint, and so takes values from 0
405 // to 0x10FFFF inclusive only.
406 b.load_range_assert(ptr, 0, 0x10FFFF + 1, llvm::False, alignment.to_align())
407 } else if (t.is_region_ptr() || t.is_box() || t.is_fn())
408 && !common::type_is_fat_ptr(ccx, t)
410 b.load_nonnull(ptr, alignment.to_align())
412 b.load(ptr, alignment.to_align())
416 /// Helper for storing values in memory. Does the necessary conversion if the in-memory type
417 /// differs from the type used for SSA values.
418 pub fn store_ty<'a, 'tcx>(cx: &Builder<'a, 'tcx>, v: ValueRef, dst: ValueRef,
419 dst_align: Alignment, t: Ty<'tcx>) {
420 debug!("store_ty: {:?} : {:?} <- {:?}", Value(dst), t, Value(v));
422 if common::type_is_fat_ptr(cx.ccx, t) {
423 let lladdr = cx.extract_value(v, abi::FAT_PTR_ADDR);
424 let llextra = cx.extract_value(v, abi::FAT_PTR_EXTRA);
425 store_fat_ptr(cx, lladdr, llextra, dst, dst_align, t);
427 cx.store(from_immediate(cx, v), dst, dst_align.to_align());
431 pub fn store_fat_ptr<'a, 'tcx>(cx: &Builder<'a, 'tcx>,
435 dst_align: Alignment,
437 // FIXME: emit metadata
438 cx.store(data, get_dataptr(cx, dst), dst_align.to_align());
439 cx.store(extra, get_meta(cx, dst), dst_align.to_align());
442 pub fn load_fat_ptr<'a, 'tcx>(
443 b: &Builder<'a, 'tcx>, src: ValueRef, alignment: Alignment, t: Ty<'tcx>
444 ) -> (ValueRef, ValueRef) {
445 let ptr = get_dataptr(b, src);
446 let ptr = if t.is_region_ptr() || t.is_box() {
447 b.load_nonnull(ptr, alignment.to_align())
449 b.load(ptr, alignment.to_align())
452 let meta = get_meta(b, src);
453 let meta_ty = val_ty(meta);
454 // If the 'meta' field is a pointer, it's a vtable, so use load_nonnull
456 let meta = if meta_ty.element_type().kind() == llvm::TypeKind::Pointer {
457 b.load_nonnull(meta, None)
465 pub fn from_immediate(bcx: &Builder, val: ValueRef) -> ValueRef {
466 if val_ty(val) == Type::i1(bcx.ccx) {
467 bcx.zext(val, Type::i8(bcx.ccx))
473 pub fn to_immediate(bcx: &Builder, val: ValueRef, ty: Ty) -> ValueRef {
475 bcx.trunc(val, Type::i1(bcx.ccx))
481 pub enum Lifetime { Start, End }
484 // If LLVM lifetime intrinsic support is enabled (i.e. optimizations
485 // on), and `ptr` is nonzero-sized, then extracts the size of `ptr`
486 // and the intrinsic for `lt` and passes them to `emit`, which is in
487 // charge of generating code to call the passed intrinsic on whatever
488 // block of generated code is targetted for the intrinsic.
490 // If LLVM lifetime intrinsic support is disabled (i.e. optimizations
491 // off) or `ptr` is zero-sized, then no-op (does not call `emit`).
492 pub fn call(self, b: &Builder, ptr: ValueRef) {
493 if b.ccx.sess().opts.optimize == config::OptLevel::No {
497 let size = machine::llsize_of_alloc(b.ccx, val_ty(ptr).element_type());
502 let lifetime_intrinsic = b.ccx.get_intrinsic(match self {
503 Lifetime::Start => "llvm.lifetime.start",
504 Lifetime::End => "llvm.lifetime.end"
507 let ptr = b.pointercast(ptr, Type::i8p(b.ccx));
508 b.call(lifetime_intrinsic, &[C_u64(b.ccx, size), ptr], None);
512 pub fn call_memcpy<'a, 'tcx>(b: &Builder<'a, 'tcx>,
518 let ptr_width = &ccx.sess().target.target.target_pointer_width;
519 let key = format!("llvm.memcpy.p0i8.p0i8.i{}", ptr_width);
520 let memcpy = ccx.get_intrinsic(&key);
521 let src_ptr = b.pointercast(src, Type::i8p(ccx));
522 let dst_ptr = b.pointercast(dst, Type::i8p(ccx));
523 let size = b.intcast(n_bytes, ccx.int_type(), false);
524 let align = C_i32(ccx, align as i32);
525 let volatile = C_bool(ccx, false);
526 b.call(memcpy, &[dst_ptr, src_ptr, size, align, volatile], None);
529 pub fn memcpy_ty<'a, 'tcx>(
530 bcx: &Builder<'a, 'tcx>,
538 let size = ccx.size_of(t);
543 let align = align.unwrap_or_else(|| ccx.align_of(t));
544 call_memcpy(bcx, dst, src, C_uint(ccx, size), align);
547 pub fn call_memset<'a, 'tcx>(b: &Builder<'a, 'tcx>,
552 volatile: bool) -> ValueRef {
553 let ptr_width = &b.ccx.sess().target.target.target_pointer_width;
554 let intrinsic_key = format!("llvm.memset.p0i8.i{}", ptr_width);
555 let llintrinsicfn = b.ccx.get_intrinsic(&intrinsic_key);
556 let volatile = C_bool(b.ccx, volatile);
557 b.call(llintrinsicfn, &[ptr, fill_byte, size, align, volatile], None)
560 pub fn trans_instance<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, instance: Instance<'tcx>) {
561 let _s = if ccx.sess().trans_stats() {
562 let mut instance_name = String::new();
563 DefPathBasedNames::new(ccx.tcx(), true, true)
564 .push_def_path(instance.def_id(), &mut instance_name);
565 Some(StatRecorder::new(ccx, instance_name))
570 // this is an info! to allow collecting monomorphization statistics
571 // and to allow finding the last function before LLVM aborts from
573 info!("trans_instance({})", instance);
575 let fn_ty = common::instance_ty(ccx.shared(), &instance);
576 let sig = common::ty_fn_sig(ccx, fn_ty);
577 let sig = ccx.tcx().erase_late_bound_regions_and_normalize(&sig);
579 let lldecl = match ccx.instances().borrow().get(&instance) {
581 None => bug!("Instance `{:?}` not already declared", instance)
584 ccx.stats().n_closures.set(ccx.stats().n_closures.get() + 1);
586 // The `uwtable` attribute according to LLVM is:
588 // This attribute indicates that the ABI being targeted requires that an
589 // unwind table entry be produced for this function even if we can show
590 // that no exceptions passes by it. This is normally the case for the
591 // ELF x86-64 abi, but it can be disabled for some compilation units.
593 // Typically when we're compiling with `-C panic=abort` (which implies this
594 // `no_landing_pads` check) we don't need `uwtable` because we can't
595 // generate any exceptions! On Windows, however, exceptions include other
596 // events such as illegal instructions, segfaults, etc. This means that on
597 // Windows we end up still needing the `uwtable` attribute even if the `-C
598 // panic=abort` flag is passed.
600 // You can also find more info on why Windows is whitelisted here in:
601 // https://bugzilla.mozilla.org/show_bug.cgi?id=1302078
602 if !ccx.sess().no_landing_pads() ||
603 ccx.sess().target.target.options.is_like_windows {
604 attributes::emit_uwtable(lldecl, true);
607 let mir = ccx.tcx().instance_mir(instance.def);
608 mir::trans_mir(ccx, lldecl, &mir, instance, sig);
611 pub fn llvm_linkage_by_name(name: &str) -> Option<Linkage> {
612 // Use the names from src/llvm/docs/LangRef.rst here. Most types are only
613 // applicable to variable declarations and may not really make sense for
614 // Rust code in the first place but whitelist them anyway and trust that
615 // the user knows what s/he's doing. Who knows, unanticipated use cases
616 // may pop up in the future.
618 // ghost, dllimport, dllexport and linkonce_odr_autohide are not supported
619 // and don't have to be, LLVM treats them as no-ops.
621 "appending" => Some(llvm::Linkage::AppendingLinkage),
622 "available_externally" => Some(llvm::Linkage::AvailableExternallyLinkage),
623 "common" => Some(llvm::Linkage::CommonLinkage),
624 "extern_weak" => Some(llvm::Linkage::ExternalWeakLinkage),
625 "external" => Some(llvm::Linkage::ExternalLinkage),
626 "internal" => Some(llvm::Linkage::InternalLinkage),
627 "linkonce" => Some(llvm::Linkage::LinkOnceAnyLinkage),
628 "linkonce_odr" => Some(llvm::Linkage::LinkOnceODRLinkage),
629 "private" => Some(llvm::Linkage::PrivateLinkage),
630 "weak" => Some(llvm::Linkage::WeakAnyLinkage),
631 "weak_odr" => Some(llvm::Linkage::WeakODRLinkage),
636 pub fn set_link_section(ccx: &CrateContext,
638 attrs: &[ast::Attribute]) {
639 if let Some(sect) = attr::first_attr_value_str_by_name(attrs, "link_section") {
640 if contains_null(§.as_str()) {
641 ccx.sess().fatal(&format!("Illegal null byte in link_section value: `{}`", §));
644 let buf = CString::new(sect.as_str().as_bytes()).unwrap();
645 llvm::LLVMSetSection(llval, buf.as_ptr());
650 /// Create the `main` function which will initialise the rust runtime and call
651 /// users main function.
652 pub fn maybe_create_entry_wrapper(ccx: &CrateContext) {
653 let (main_def_id, span) = match *ccx.sess().entry_fn.borrow() {
654 Some((id, span)) => {
655 (ccx.tcx().hir.local_def_id(id), span)
660 // check for the #[rustc_error] annotation, which forces an
661 // error in trans. This is used to write compile-fail tests
662 // that actually test that compilation succeeds without
663 // reporting an error.
664 if ccx.tcx().has_attr(main_def_id, "rustc_error") {
665 ccx.tcx().sess.span_fatal(span, "compilation successful");
668 let instance = Instance::mono(ccx.tcx(), main_def_id);
670 if !ccx.codegen_unit().contains_item(&TransItem::Fn(instance)) {
671 // We want to create the wrapper in the same codegen unit as Rust's main
676 let main_llfn = callee::get_fn(ccx, instance);
678 let et = ccx.sess().entry_type.get().unwrap();
680 config::EntryMain => create_entry_fn(ccx, span, main_llfn, true),
681 config::EntryStart => create_entry_fn(ccx, span, main_llfn, false),
682 config::EntryNone => {} // Do nothing.
685 fn create_entry_fn(ccx: &CrateContext,
688 use_start_lang_item: bool) {
689 let llfty = Type::func(&[ccx.int_type(), Type::i8p(ccx).ptr_to()], &ccx.int_type());
691 if declare::get_defined_value(ccx, "main").is_some() {
692 // FIXME: We should be smart and show a better diagnostic here.
693 ccx.sess().struct_span_err(sp, "entry symbol `main` defined multiple times")
694 .help("did you use #[no_mangle] on `fn main`? Use #[start] instead")
696 ccx.sess().abort_if_errors();
699 let llfn = declare::declare_cfn(ccx, "main", llfty);
701 // `main` should respect same config for frame pointer elimination as rest of code
702 attributes::set_frame_pointer_elimination(ccx, llfn);
704 let bld = Builder::new_block(ccx, llfn, "top");
706 debuginfo::gdb::insert_reference_to_gdb_debug_scripts_section_global(ccx, &bld);
708 let (start_fn, args) = if use_start_lang_item {
709 let start_def_id = ccx.tcx().require_lang_item(StartFnLangItem);
710 let start_instance = Instance::mono(ccx.tcx(), start_def_id);
711 let start_fn = callee::get_fn(ccx, start_instance);
712 (start_fn, vec![bld.pointercast(rust_main, Type::i8p(ccx).ptr_to()), get_param(llfn, 0),
715 debug!("using user-defined start fn");
716 (rust_main, vec![get_param(llfn, 0 as c_uint), get_param(llfn, 1 as c_uint)])
719 let result = bld.call(start_fn, &args, None);
724 fn contains_null(s: &str) -> bool {
725 s.bytes().any(|b| b == 0)
728 fn write_metadata<'a, 'gcx>(tcx: TyCtxt<'a, 'gcx, 'gcx>,
729 link_meta: &LinkMeta,
730 exported_symbols: &NodeSet)
731 -> (ContextRef, ModuleRef, EncodedMetadata) {
734 let (metadata_llcx, metadata_llmod) = unsafe {
735 context::create_context_and_module(tcx.sess, "metadata")
738 #[derive(PartialEq, Eq, PartialOrd, Ord)]
745 let kind = tcx.sess.crate_types.borrow().iter().map(|ty| {
747 config::CrateTypeExecutable |
748 config::CrateTypeStaticlib |
749 config::CrateTypeCdylib => MetadataKind::None,
751 config::CrateTypeRlib => MetadataKind::Uncompressed,
753 config::CrateTypeDylib |
754 config::CrateTypeProcMacro => MetadataKind::Compressed,
758 if kind == MetadataKind::None {
759 return (metadata_llcx, metadata_llmod, EncodedMetadata {
765 let cstore = &tcx.sess.cstore;
766 let metadata = cstore.encode_metadata(tcx,
769 if kind == MetadataKind::Uncompressed {
770 return (metadata_llcx, metadata_llmod, metadata);
773 assert!(kind == MetadataKind::Compressed);
774 let mut compressed = cstore.metadata_encoding_version().to_vec();
775 compressed.extend_from_slice(&flate::deflate_bytes(&metadata.raw_data));
777 let llmeta = C_bytes_in_context(metadata_llcx, &compressed);
778 let llconst = C_struct_in_context(metadata_llcx, &[llmeta], false);
779 let name = symbol_export::metadata_symbol_name(tcx);
780 let buf = CString::new(name).unwrap();
781 let llglobal = unsafe {
782 llvm::LLVMAddGlobal(metadata_llmod, val_ty(llconst).to_ref(), buf.as_ptr())
785 llvm::LLVMSetInitializer(llglobal, llconst);
787 tcx.sess.cstore.metadata_section_name(&tcx.sess.target.target);
788 let name = CString::new(section_name).unwrap();
789 llvm::LLVMSetSection(llglobal, name.as_ptr());
791 // Also generate a .section directive to force no
792 // flags, at least for ELF outputs, so that the
793 // metadata doesn't get loaded into memory.
794 let directive = format!(".section {}", section_name);
795 let directive = CString::new(directive).unwrap();
796 llvm::LLVMSetModuleInlineAsm(metadata_llmod, directive.as_ptr())
798 return (metadata_llcx, metadata_llmod, metadata);
801 /// Find any symbols that are defined in one compilation unit, but not declared
802 /// in any other compilation unit. Give these symbols internal linkage.
803 fn internalize_symbols<'a, 'tcx>(sess: &Session,
804 scx: &SharedCrateContext<'a, 'tcx>,
805 llvm_modules: &[ModuleLlvm],
806 symbol_map: &SymbolMap<'tcx>,
807 exported_symbols: &ExportedSymbols) {
808 let export_threshold =
809 symbol_export::crates_export_threshold(&sess.crate_types.borrow());
811 let exported_symbols = exported_symbols
812 .exported_symbols(LOCAL_CRATE)
814 .filter(|&&(_, export_level)| {
815 symbol_export::is_below_threshold(export_level, export_threshold)
817 .map(|&(ref name, _)| &name[..])
818 .collect::<FxHashSet<&str>>();
822 let incr_comp = sess.opts.debugging_opts.incremental.is_some();
824 // 'unsafe' because we are holding on to CStr's from the LLVM module within
827 let mut referenced_somewhere = FxHashSet();
829 // Collect all symbols that need to stay externally visible because they
830 // are referenced via a declaration in some other codegen unit. In
831 // incremental compilation, we don't need to collect. See below for more
834 for ll in llvm_modules {
835 for val in iter_globals(ll.llmod).chain(iter_functions(ll.llmod)) {
836 let linkage = llvm::LLVMRustGetLinkage(val);
837 // We only care about external declarations (not definitions)
838 // and available_externally definitions.
839 let is_available_externally =
840 linkage == llvm::Linkage::AvailableExternallyLinkage;
841 let is_decl = llvm::LLVMIsDeclaration(val) == llvm::True;
843 if is_decl || is_available_externally {
844 let symbol_name = CStr::from_ptr(llvm::LLVMGetValueName(val));
845 referenced_somewhere.insert(symbol_name);
851 // Also collect all symbols for which we cannot adjust linkage, because
852 // it is fixed by some directive in the source code.
853 let (locally_defined_symbols, linkage_fixed_explicitly) = {
854 let mut locally_defined_symbols = FxHashSet();
855 let mut linkage_fixed_explicitly = FxHashSet();
857 for trans_item in scx.translation_items().borrow().iter() {
858 let symbol_name = symbol_map.get_or_compute(scx, *trans_item);
859 if trans_item.explicit_linkage(tcx).is_some() {
860 linkage_fixed_explicitly.insert(symbol_name.clone());
862 locally_defined_symbols.insert(symbol_name);
865 (locally_defined_symbols, linkage_fixed_explicitly)
868 // Examine each external definition. If the definition is not used in
869 // any other compilation unit, and is not reachable from other crates,
870 // then give it internal linkage.
871 for ll in llvm_modules {
872 for val in iter_globals(ll.llmod).chain(iter_functions(ll.llmod)) {
873 let linkage = llvm::LLVMRustGetLinkage(val);
875 let is_externally_visible = (linkage == llvm::Linkage::ExternalLinkage) ||
876 (linkage == llvm::Linkage::LinkOnceODRLinkage) ||
877 (linkage == llvm::Linkage::WeakODRLinkage);
879 if !is_externally_visible {
880 // This symbol is not visible outside of its codegen unit,
881 // so there is nothing to do for it.
885 let name_cstr = CStr::from_ptr(llvm::LLVMGetValueName(val));
886 let name_str = name_cstr.to_str().unwrap();
888 if exported_symbols.contains(&name_str) {
889 // This symbol is explicitly exported, so we can't
890 // mark it as internal or hidden.
894 let is_declaration = llvm::LLVMIsDeclaration(val) == llvm::True;
897 if locally_defined_symbols.contains(name_str) {
898 // Only mark declarations from the current crate as hidden.
899 // Otherwise we would mark things as hidden that are
900 // imported from other crates or native libraries.
901 llvm::LLVMRustSetVisibility(val, llvm::Visibility::Hidden);
904 let has_fixed_linkage = linkage_fixed_explicitly.contains(name_str);
906 if !has_fixed_linkage {
907 // In incremental compilation mode, we can't be sure that
908 // we saw all references because we don't know what's in
909 // cached compilation units, so we always assume that the
910 // given item has been referenced.
911 if incr_comp || referenced_somewhere.contains(&name_cstr) {
912 llvm::LLVMRustSetVisibility(val, llvm::Visibility::Hidden);
914 llvm::LLVMRustSetLinkage(val, llvm::Linkage::InternalLinkage);
917 llvm::LLVMSetDLLStorageClass(val, llvm::DLLStorageClass::Default);
918 llvm::UnsetComdat(val);
926 // Create a `__imp_<symbol> = &symbol` global for every public static `symbol`.
927 // This is required to satisfy `dllimport` references to static data in .rlibs
928 // when using MSVC linker. We do this only for data, as linker can fix up
929 // code references on its own.
930 // See #26591, #27438
931 fn create_imps(sess: &Session,
932 llvm_modules: &[ModuleLlvm]) {
933 // The x86 ABI seems to require that leading underscores are added to symbol
934 // names, so we need an extra underscore on 32-bit. There's also a leading
935 // '\x01' here which disables LLVM's symbol mangling (e.g. no extra
936 // underscores added in front).
937 let prefix = if sess.target.target.target_pointer_width == "32" {
943 for ll in llvm_modules {
944 let exported: Vec<_> = iter_globals(ll.llmod)
946 llvm::LLVMRustGetLinkage(val) ==
947 llvm::Linkage::ExternalLinkage &&
948 llvm::LLVMIsDeclaration(val) == 0
952 let i8p_ty = Type::i8p_llcx(ll.llcx);
953 for val in exported {
954 let name = CStr::from_ptr(llvm::LLVMGetValueName(val));
955 let mut imp_name = prefix.as_bytes().to_vec();
956 imp_name.extend(name.to_bytes());
957 let imp_name = CString::new(imp_name).unwrap();
958 let imp = llvm::LLVMAddGlobal(ll.llmod,
960 imp_name.as_ptr() as *const _);
961 let init = llvm::LLVMConstBitCast(val, i8p_ty.to_ref());
962 llvm::LLVMSetInitializer(imp, init);
963 llvm::LLVMRustSetLinkage(imp, llvm::Linkage::ExternalLinkage);
971 step: unsafe extern "C" fn(ValueRef) -> ValueRef,
974 impl Iterator for ValueIter {
975 type Item = ValueRef;
977 fn next(&mut self) -> Option<ValueRef> {
980 self.cur = unsafe { (self.step)(old) };
988 fn iter_globals(llmod: llvm::ModuleRef) -> ValueIter {
991 cur: llvm::LLVMGetFirstGlobal(llmod),
992 step: llvm::LLVMGetNextGlobal,
997 fn iter_functions(llmod: llvm::ModuleRef) -> ValueIter {
1000 cur: llvm::LLVMGetFirstFunction(llmod),
1001 step: llvm::LLVMGetNextFunction,
1006 /// The context provided lists a set of reachable ids as calculated by
1007 /// middle::reachable, but this contains far more ids and symbols than we're
1008 /// actually exposing from the object file. This function will filter the set in
1009 /// the context to the set of ids which correspond to symbols that are exposed
1010 /// from the object file being generated.
1012 /// This list is later used by linkers to determine the set of symbols needed to
1013 /// be exposed from a dynamic library and it's also encoded into the metadata.
1014 pub fn find_exported_symbols(tcx: TyCtxt, reachable: NodeSet) -> NodeSet {
1015 reachable.into_iter().filter(|&id| {
1016 // Next, we want to ignore some FFI functions that are not exposed from
1017 // this crate. Reachable FFI functions can be lumped into two
1020 // 1. Those that are included statically via a static library
1021 // 2. Those included otherwise (e.g. dynamically or via a framework)
1023 // Although our LLVM module is not literally emitting code for the
1024 // statically included symbols, it's an export of our library which
1025 // needs to be passed on to the linker and encoded in the metadata.
1027 // As a result, if this id is an FFI item (foreign item) then we only
1028 // let it through if it's included statically.
1029 match tcx.hir.get(id) {
1030 hir_map::NodeForeignItem(..) => {
1031 let def_id = tcx.hir.local_def_id(id);
1032 tcx.sess.cstore.is_statically_included_foreign_item(def_id)
1035 // Only consider nodes that actually have exported symbols.
1036 hir_map::NodeItem(&hir::Item {
1037 node: hir::ItemStatic(..), .. }) |
1038 hir_map::NodeItem(&hir::Item {
1039 node: hir::ItemFn(..), .. }) |
1040 hir_map::NodeImplItem(&hir::ImplItem {
1041 node: hir::ImplItemKind::Method(..), .. }) => {
1042 let def_id = tcx.hir.local_def_id(id);
1043 let generics = tcx.item_generics(def_id);
1044 let attributes = tcx.get_attrs(def_id);
1045 (generics.parent_types == 0 && generics.types.is_empty()) &&
1046 // Functions marked with #[inline] are only ever translated
1047 // with "internal" linkage and are never exported.
1048 !attr::requests_inline(&attributes)
1056 pub fn trans_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
1057 analysis: ty::CrateAnalysis,
1058 incremental_hashes_map: &IncrementalHashesMap)
1059 -> CrateTranslation {
1060 // Be careful with this krate: obviously it gives access to the
1061 // entire contents of the krate. So if you push any subtasks of
1062 // `TransCrate`, you need to be careful to register "reads" of the
1063 // particular items that will be processed.
1064 let krate = tcx.hir.krate();
1066 let ty::CrateAnalysis { reachable, .. } = analysis;
1067 let exported_symbols = find_exported_symbols(tcx, reachable);
1069 let check_overflow = tcx.sess.overflow_checks();
1071 let link_meta = link::build_link_meta(incremental_hashes_map);
1073 let shared_ccx = SharedCrateContext::new(tcx,
1076 // Translate the metadata.
1077 let (metadata_llcx, metadata_llmod, metadata) =
1078 time(tcx.sess.time_passes(), "write metadata", || {
1079 write_metadata(tcx, &link_meta, shared_ccx.exported_symbols())
1082 let metadata_module = ModuleTranslation {
1083 name: link::METADATA_MODULE_NAME.to_string(),
1084 symbol_name_hash: 0, // we always rebuild metadata, at least for now
1085 source: ModuleSource::Translated(ModuleLlvm {
1086 llcx: metadata_llcx,
1087 llmod: metadata_llmod,
1090 let no_builtins = attr::contains_name(&krate.attrs, "no_builtins");
1092 // Skip crate items and just output metadata in -Z no-trans mode.
1093 if tcx.sess.opts.debugging_opts.no_trans ||
1094 !tcx.sess.opts.output_types.should_trans() {
1095 let empty_exported_symbols = ExportedSymbols::empty();
1096 let linker_info = LinkerInfo::new(&shared_ccx, &empty_exported_symbols);
1097 return CrateTranslation {
1098 crate_name: tcx.crate_name(LOCAL_CRATE),
1100 metadata_module: metadata_module,
1103 exported_symbols: empty_exported_symbols,
1104 no_builtins: no_builtins,
1105 linker_info: linker_info,
1106 windows_subsystem: None,
1110 // Run the translation item collector and partition the collected items into
1112 let (codegen_units, symbol_map) = collect_and_partition_translation_items(&shared_ccx);
1114 let symbol_map = Rc::new(symbol_map);
1116 let mut all_stats = Stats::default();
1117 let modules: Vec<ModuleTranslation> = codegen_units
1120 let dep_node = cgu.work_product_dep_node();
1121 let (stats, module) =
1122 tcx.dep_graph.with_task(dep_node,
1123 AssertDepGraphSafe(&shared_ccx),
1124 AssertDepGraphSafe((cgu, symbol_map.clone())),
1125 module_translation);
1126 all_stats.extend(stats);
1131 fn module_translation<'a, 'tcx>(
1132 scx: AssertDepGraphSafe<&SharedCrateContext<'a, 'tcx>>,
1133 args: AssertDepGraphSafe<(CodegenUnit<'tcx>, Rc<SymbolMap<'tcx>>)>)
1134 -> (Stats, ModuleTranslation)
1136 // FIXME(#40304): We ought to be using the id as a key and some queries, I think.
1137 let AssertDepGraphSafe(scx) = scx;
1138 let AssertDepGraphSafe((cgu, symbol_map)) = args;
1140 let cgu_name = String::from(cgu.name());
1141 let cgu_id = cgu.work_product_id();
1142 let symbol_name_hash = cgu.compute_symbol_name_hash(scx, &symbol_map);
1144 // Check whether there is a previous work-product we can
1145 // re-use. Not only must the file exist, and the inputs not
1146 // be dirty, but the hash of the symbols we will generate must
1148 let previous_work_product =
1149 scx.dep_graph().previous_work_product(&cgu_id).and_then(|work_product| {
1150 if work_product.input_hash == symbol_name_hash {
1151 debug!("trans_reuse_previous_work_products: reusing {:?}", work_product);
1154 if scx.sess().opts.debugging_opts.incremental_info {
1155 println!("incremental: CGU `{}` invalidated because of \
1156 changed partitioning hash.",
1159 debug!("trans_reuse_previous_work_products: \
1160 not reusing {:?} because hash changed to {:?}",
1161 work_product, symbol_name_hash);
1166 if let Some(buf) = previous_work_product {
1167 // Don't need to translate this module.
1168 let module = ModuleTranslation {
1171 source: ModuleSource::Preexisting(buf.clone())
1173 return (Stats::default(), module);
1176 // Instantiate translation items without filling out definitions yet...
1177 let lcx = LocalCrateContext::new(scx, cgu, symbol_map.clone());
1179 let ccx = CrateContext::new(scx, &lcx);
1180 let trans_items = ccx.codegen_unit()
1181 .items_in_deterministic_order(ccx.tcx(), &symbol_map);
1182 for &(trans_item, linkage) in &trans_items {
1183 trans_item.predefine(&ccx, linkage);
1186 // ... and now that we have everything pre-defined, fill out those definitions.
1187 for &(trans_item, _) in &trans_items {
1188 trans_item.define(&ccx);
1191 // If this codegen unit contains the main function, also create the
1193 maybe_create_entry_wrapper(&ccx);
1195 // Run replace-all-uses-with for statics that need it
1196 for &(old_g, new_g) in ccx.statics_to_rauw().borrow().iter() {
1198 let bitcast = llvm::LLVMConstPointerCast(new_g, llvm::LLVMTypeOf(old_g));
1199 llvm::LLVMReplaceAllUsesWith(old_g, bitcast);
1200 llvm::LLVMDeleteGlobal(old_g);
1204 // Create the llvm.used variable
1205 // This variable has type [N x i8*] and is stored in the llvm.metadata section
1206 if !ccx.used_statics().borrow().is_empty() {
1207 let name = CString::new("llvm.used").unwrap();
1208 let section = CString::new("llvm.metadata").unwrap();
1209 let array = C_array(Type::i8(&ccx).ptr_to(), &*ccx.used_statics().borrow());
1212 let g = llvm::LLVMAddGlobal(ccx.llmod(),
1213 val_ty(array).to_ref(),
1215 llvm::LLVMSetInitializer(g, array);
1216 llvm::LLVMRustSetLinkage(g, llvm::Linkage::AppendingLinkage);
1217 llvm::LLVMSetSection(g, section.as_ptr());
1221 // Finalize debuginfo
1222 if ccx.sess().opts.debuginfo != NoDebugInfo {
1223 debuginfo::finalize(&ccx);
1229 source: ModuleSource::Translated(ModuleLlvm {
1236 (lcx.into_stats(), module)
1239 assert_module_sources::assert_module_sources(tcx, &modules);
1241 symbol_names_test::report_symbol_names(&shared_ccx);
1243 if shared_ccx.sess().trans_stats() {
1244 println!("--- trans stats ---");
1245 println!("n_glues_created: {}", all_stats.n_glues_created.get());
1246 println!("n_null_glues: {}", all_stats.n_null_glues.get());
1247 println!("n_real_glues: {}", all_stats.n_real_glues.get());
1249 println!("n_fns: {}", all_stats.n_fns.get());
1250 println!("n_inlines: {}", all_stats.n_inlines.get());
1251 println!("n_closures: {}", all_stats.n_closures.get());
1252 println!("fn stats:");
1253 all_stats.fn_stats.borrow_mut().sort_by(|&(_, insns_a), &(_, insns_b)| {
1254 insns_b.cmp(&insns_a)
1256 for tuple in all_stats.fn_stats.borrow().iter() {
1258 (ref name, insns) => {
1259 println!("{} insns, {}", insns, *name);
1265 if shared_ccx.sess().count_llvm_insns() {
1266 for (k, v) in all_stats.llvm_insns.borrow().iter() {
1267 println!("{:7} {}", *v, *k);
1271 let sess = shared_ccx.sess();
1273 let exported_symbols = ExportedSymbols::compute_from(&shared_ccx,
1276 // Get the list of llvm modules we created. We'll do a few wacky
1277 // transforms on them now.
1279 let llvm_modules: Vec<_> =
1281 .filter_map(|module| match module.source {
1282 ModuleSource::Translated(llvm) => Some(llvm),
1287 // Now that we have all symbols that are exported from the CGUs of this
1288 // crate, we can run the `internalize_symbols` pass.
1289 time(shared_ccx.sess().time_passes(), "internalize symbols", || {
1290 internalize_symbols(sess,
1297 if tcx.sess.opts.debugging_opts.print_type_sizes {
1298 gather_type_sizes(tcx);
1301 if sess.target.target.options.is_like_msvc &&
1302 sess.crate_types.borrow().iter().any(|ct| *ct == config::CrateTypeRlib) {
1303 create_imps(sess, &llvm_modules);
1306 let linker_info = LinkerInfo::new(&shared_ccx, &exported_symbols);
1308 let subsystem = attr::first_attr_value_str_by_name(&krate.attrs,
1309 "windows_subsystem");
1310 let windows_subsystem = subsystem.map(|subsystem| {
1311 if subsystem != "windows" && subsystem != "console" {
1312 tcx.sess.fatal(&format!("invalid windows subsystem `{}`, only \
1313 `windows` and `console` are allowed",
1316 subsystem.to_string()
1320 crate_name: tcx.crate_name(LOCAL_CRATE),
1322 metadata_module: metadata_module,
1325 exported_symbols: exported_symbols,
1326 no_builtins: no_builtins,
1327 linker_info: linker_info,
1328 windows_subsystem: windows_subsystem,
1332 fn gather_type_sizes<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
1333 let layout_cache = tcx.layout_cache.borrow();
1334 for (ty, layout) in layout_cache.iter() {
1336 // (delay format until we actually need it)
1337 let record = |kind, opt_discr_size, variants| {
1338 let type_desc = format!("{:?}", ty);
1339 let overall_size = layout.size(tcx);
1340 let align = layout.align(tcx);
1341 tcx.sess.code_stats.borrow_mut().record_type_size(kind,
1349 let (adt_def, substs) = match ty.sty {
1350 ty::TyAdt(ref adt_def, substs) => {
1351 debug!("print-type-size t: `{:?}` process adt", ty);
1355 ty::TyClosure(..) => {
1356 debug!("print-type-size t: `{:?}` record closure", ty);
1357 record(DataTypeKind::Closure, None, vec![]);
1362 debug!("print-type-size t: `{:?}` skip non-nominal", ty);
1367 let adt_kind = adt_def.adt_kind();
1369 let build_field_info = |(field_name, field_ty): (ast::Name, Ty), offset: &layout::Size| {
1370 match layout_cache.get(&field_ty) {
1371 None => bug!("no layout found for field {} type: `{:?}`", field_name, field_ty),
1372 Some(field_layout) => {
1373 session::FieldInfo {
1374 name: field_name.to_string(),
1375 offset: offset.bytes(),
1376 size: field_layout.size(tcx).bytes(),
1377 align: field_layout.align(tcx).abi(),
1383 let build_primitive_info = |name: ast::Name, value: &layout::Primitive| {
1384 session::VariantInfo {
1385 name: Some(name.to_string()),
1386 kind: session::SizeKind::Exact,
1387 align: value.align(tcx).abi(),
1388 size: value.size(tcx).bytes(),
1394 WithDiscrim(&'a layout::Struct),
1395 NoDiscrim(&'a layout::Struct),
1398 let build_variant_info = |n: Option<ast::Name>, flds: &[(ast::Name, Ty)], layout: Fields| {
1399 let (s, field_offsets) = match layout {
1400 Fields::WithDiscrim(s) => (s, &s.offsets[1..]),
1401 Fields::NoDiscrim(s) => (s, &s.offsets[0..]),
1403 let field_info: Vec<_> = flds.iter()
1404 .zip(field_offsets.iter())
1405 .map(|(&field_name_ty, offset)| build_field_info(field_name_ty, offset))
1408 session::VariantInfo {
1409 name: n.map(|n|n.to_string()),
1411 session::SizeKind::Exact
1413 session::SizeKind::Min
1415 align: s.align.abi(),
1416 size: s.min_size.bytes(),
1422 Layout::StructWrappedNullablePointer { nonnull: ref variant_layout,
1425 discrfield_source: _ } => {
1426 debug!("print-type-size t: `{:?}` adt struct-wrapped nullable nndiscr {} is {:?}",
1427 ty, nndiscr, variant_layout);
1428 let variant_def = &adt_def.variants[nndiscr as usize];
1429 let fields: Vec<_> = variant_def.fields.iter()
1430 .map(|field_def| (field_def.name, field_def.ty(tcx, substs)))
1432 record(adt_kind.into(),
1434 vec![build_variant_info(Some(variant_def.name),
1436 Fields::NoDiscrim(variant_layout))]);
1438 Layout::RawNullablePointer { nndiscr, value } => {
1439 debug!("print-type-size t: `{:?}` adt raw nullable nndiscr {} is {:?}",
1440 ty, nndiscr, value);
1441 let variant_def = &adt_def.variants[nndiscr as usize];
1442 record(adt_kind.into(), None,
1443 vec![build_primitive_info(variant_def.name, &value)]);
1445 Layout::Univariant { variant: ref variant_layout, non_zero: _ } => {
1446 let variant_names = || {
1447 adt_def.variants.iter().map(|v|format!("{}", v.name)).collect::<Vec<_>>()
1449 debug!("print-type-size t: `{:?}` adt univariant {:?} variants: {:?}",
1450 ty, variant_layout, variant_names());
1451 assert!(adt_def.variants.len() <= 1,
1452 "univariant with variants {:?}", variant_names());
1453 if adt_def.variants.len() == 1 {
1454 let variant_def = &adt_def.variants[0];
1455 let fields: Vec<_> = variant_def.fields.iter()
1456 .map(|field_def| (field_def.name, field_def.ty(tcx, substs)))
1458 record(adt_kind.into(),
1460 vec![build_variant_info(Some(variant_def.name),
1462 Fields::NoDiscrim(variant_layout))]);
1464 // (This case arises for *empty* enums; so give it
1466 record(adt_kind.into(), None, vec![]);
1470 Layout::General { ref variants, discr, .. } => {
1471 debug!("print-type-size t: `{:?}` adt general variants def {} layouts {} {:?}",
1472 ty, adt_def.variants.len(), variants.len(), variants);
1473 let variant_infos: Vec<_> = adt_def.variants.iter()
1474 .zip(variants.iter())
1475 .map(|(variant_def, variant_layout)| {
1476 let fields: Vec<_> = variant_def.fields.iter()
1477 .map(|field_def| (field_def.name, field_def.ty(tcx, substs)))
1479 build_variant_info(Some(variant_def.name),
1481 Fields::WithDiscrim(variant_layout))
1484 record(adt_kind.into(), Some(discr.size()), variant_infos);
1487 Layout::UntaggedUnion { ref variants } => {
1488 debug!("print-type-size t: `{:?}` adt union variants {:?}",
1490 // layout does not currently store info about each
1492 record(adt_kind.into(), None, Vec::new());
1495 Layout::CEnum { discr, .. } => {
1496 debug!("print-type-size t: `{:?}` adt c-like enum", ty);
1497 let variant_infos: Vec<_> = adt_def.variants.iter()
1498 .map(|variant_def| {
1499 build_primitive_info(variant_def.name,
1500 &layout::Primitive::Int(discr))
1503 record(adt_kind.into(), Some(discr.size()), variant_infos);
1506 // other cases provide little interesting (i.e. adjustable
1507 // via representation tweaks) size info beyond total size.
1508 Layout::Scalar { .. } |
1509 Layout::Vector { .. } |
1510 Layout::Array { .. } |
1511 Layout::FatPointer { .. } => {
1512 debug!("print-type-size t: `{:?}` adt other", ty);
1513 record(adt_kind.into(), None, Vec::new())
1519 fn collect_and_partition_translation_items<'a, 'tcx>(scx: &SharedCrateContext<'a, 'tcx>)
1520 -> (Vec<CodegenUnit<'tcx>>, SymbolMap<'tcx>) {
1521 let time_passes = scx.sess().time_passes();
1523 let collection_mode = match scx.sess().opts.debugging_opts.print_trans_items {
1525 let mode_string = s.to_lowercase();
1526 let mode_string = mode_string.trim();
1527 if mode_string == "eager" {
1528 TransItemCollectionMode::Eager
1530 if mode_string != "lazy" {
1531 let message = format!("Unknown codegen-item collection mode '{}'. \
1532 Falling back to 'lazy' mode.",
1534 scx.sess().warn(&message);
1537 TransItemCollectionMode::Lazy
1540 None => TransItemCollectionMode::Lazy
1543 let (items, inlining_map) =
1544 time(time_passes, "translation item collection", || {
1545 collector::collect_crate_translation_items(&scx, collection_mode)
1548 let symbol_map = SymbolMap::build(scx, items.iter().cloned());
1550 let strategy = if scx.sess().opts.debugging_opts.incremental.is_some() {
1551 PartitioningStrategy::PerModule
1553 PartitioningStrategy::FixedUnitCount(scx.sess().opts.cg.codegen_units)
1556 let codegen_units = time(time_passes, "codegen unit partitioning", || {
1557 partitioning::partition(scx,
1558 items.iter().cloned(),
1563 assert!(scx.tcx().sess.opts.cg.codegen_units == codegen_units.len() ||
1564 scx.tcx().sess.opts.debugging_opts.incremental.is_some());
1567 let mut ccx_map = scx.translation_items().borrow_mut();
1569 for trans_item in items.iter().cloned() {
1570 ccx_map.insert(trans_item);
1574 if scx.sess().opts.debugging_opts.print_trans_items.is_some() {
1575 let mut item_to_cgus = FxHashMap();
1577 for cgu in &codegen_units {
1578 for (&trans_item, &linkage) in cgu.items() {
1579 item_to_cgus.entry(trans_item)
1580 .or_insert(Vec::new())
1581 .push((cgu.name().clone(), linkage));
1585 let mut item_keys: Vec<_> = items
1588 let mut output = i.to_string(scx.tcx());
1589 output.push_str(" @@");
1590 let mut empty = Vec::new();
1591 let mut cgus = item_to_cgus.get_mut(i).unwrap_or(&mut empty);
1592 cgus.as_mut_slice().sort_by_key(|&(ref name, _)| name.clone());
1594 for &(ref cgu_name, linkage) in cgus.iter() {
1595 output.push_str(" ");
1596 output.push_str(&cgu_name);
1598 let linkage_abbrev = match linkage {
1599 llvm::Linkage::ExternalLinkage => "External",
1600 llvm::Linkage::AvailableExternallyLinkage => "Available",
1601 llvm::Linkage::LinkOnceAnyLinkage => "OnceAny",
1602 llvm::Linkage::LinkOnceODRLinkage => "OnceODR",
1603 llvm::Linkage::WeakAnyLinkage => "WeakAny",
1604 llvm::Linkage::WeakODRLinkage => "WeakODR",
1605 llvm::Linkage::AppendingLinkage => "Appending",
1606 llvm::Linkage::InternalLinkage => "Internal",
1607 llvm::Linkage::PrivateLinkage => "Private",
1608 llvm::Linkage::ExternalWeakLinkage => "ExternalWeak",
1609 llvm::Linkage::CommonLinkage => "Common",
1612 output.push_str("[");
1613 output.push_str(linkage_abbrev);
1614 output.push_str("]");
1622 for item in item_keys {
1623 println!("TRANS_ITEM {}", item);
1627 (codegen_units, symbol_map)