Commit Graph

247 Commits

Author SHA1 Message Date
Rafael Espindola 816127ea17 Initialize OffsetMap in a known location.
This is a small optimization and avoids the need to use call_once.

llvm-svn: 328686
2018-03-28 03:20:18 +00:00
Rafael Espindola 92eba0e14a Define a trivial method inline.
llvm-svn: 328685
2018-03-28 03:14:11 +00:00
Rafael Espindola 5a7ca96e2d Store live offsets as uint32_t.
We don't support input merge sections larger than 4gb, so these can be
uint32_t.

llvm-svn: 328684
2018-03-28 02:32:31 +00:00
Rafael Espindola 4f058a2c6b Add a SectionBase::getVA helper. NFC.
There were a few too many places duplicating this.

llvm-svn: 328402
2018-03-24 00:35:11 +00:00
Rui Ueyama ac114d27ae s/uncompress/decompress/g.
In lld, we use both "uncompress" and "decompress" which is confusing.
Since LLVM uses "decompress", we should use the same term.

llvm-svn: 324944
2018-02-12 21:56:14 +00:00
Rafael Espindola c7945c827d Move function to the file where it is used.
llvm-svn: 323780
2018-01-30 16:24:04 +00:00
Rafael Espindola 9a84f6b954 Detemplate reportDuplicate.
We normally avoid "switch (Config->EKind)", but in this case I think
it is worth it.

It is only executed when there is an error and it allows detemplating
a lot of code.

llvm-svn: 321404
2017-12-23 17:21:39 +00:00
Rafael Espindola ce3b52c186 Pass an InputFile to the InputSection constructor.
This simplifies toRegularSection and reduces the noise in a followup
patch.

llvm-svn: 321240
2017-12-21 02:11:51 +00:00
Rafael Espindola 604032729c Convert a few more InputFiles to references.
We use null files in sections to represent linker created sections,
so ObjFile<ELFT> is never null.

llvm-svn: 321238
2017-12-21 02:03:39 +00:00
Rafael Espindola 5c73c49c9f Detemplate createCommentSection.
It was only templated so it could create a dummy section header that
was immediately parsed back.

llvm-svn: 321235
2017-12-21 01:21:59 +00:00
Rafael Espindola f4fb5fd752 Move Repl to SectionBase.
It is currently in InputSectionBase. Only InputSections are used in
ICF, so Repl should be move to InputSection to clear the class
hierarchy or, like this patch does, to SectionBase for convenience.

The convenience of having it on the base class is that we can just
access the replacement without having to first check if it is an
InputSection. It is a bit less code and a bit faster as some of this
code is very hot.

I got up to 1.77% improvement in clang-gdb-index and no regressions
according to lnt.

llvm-svn: 320654
2017-12-13 22:59:23 +00:00
Rafael Espindola b01cd86458 Fix the type of the Discared section.
It is constructed with a kind of Regular and will dyn_cast to
InputSection, but is declared to be an InputSectionBase.

llvm-svn: 320539
2017-12-13 01:39:35 +00:00
Rafael Espindola 10bcc1cf90 Fix line endings. NFC.
llvm-svn: 320502
2017-12-12 17:37:01 +00:00
James Henderson 8d0efdd5db [ELF] Reset OutputSection size prior to processing linker script commands
The size of an OutputSection is calculated early, to aid handling of compressed
debug sections. However, subsequent to this point, unused synthetic sections are
removed. In the event that an OutputSection, from which such an InputSection is
removed, is still required (e.g. because it has a symbol assignment), and no longer
has any InputSections, dot assignments, or BYTE()-family directives, the size
member is never updated when processing the commands. If the removed InputSection
had a non-zero size (such as a .got.plt section), the section ends up with the
wrong size in the output.

The fix is to reset the OutputSection size prior to processing the linker script
commands relating to that OutputSection. This ensures that the size is correct even
in the above situation.

Additionally, to reduce the risk of developers misusing OutputSection Size and
InputSection OutSecOff, they are set to simply the number of InputSections in an
OutputSection, and the corresponding index respectively. We cannot completely
stop using them, due to SHF_LINK_ORDER sections requiring them.

Compressed debug sections also require the full size. This is now calculated in
maybeCompress for these kinds of sections.

Reviewers: ruiu, rafael

Differential Revision: https://reviews.llvm.org/D38361

llvm-svn: 320472
2017-12-12 11:51:13 +00:00
Rafael Espindola bdcfb178b5 Delete dead code.
llvm-svn: 319403
2017-11-30 05:52:42 +00:00
Peter Collingbourne e9a9e0a1e7 ELF: Merge DefinedRegular and Defined.
Now that DefinedRegular is the only remaining derived class of
Defined, we can merge the two classes.

Differential Revision: https://reviews.llvm.org/D39667

llvm-svn: 317448
2017-11-06 04:35:31 +00:00
Peter Collingbourne 6c55a70838 ELF: Remove DefinedCommon.
Common symbols are now represented with a DefinedRegular that points
to a BssSection, even during symbol resolution.

Differential Revision: https://reviews.llvm.org/D39666

llvm-svn: 317447
2017-11-06 04:33:58 +00:00
Rui Ueyama f52496e1e0 Rename SymbolBody -> Symbol
Now that we have only SymbolBody as the symbol class. So, "SymbolBody"
is a bit strange name now. This is a mechanical change generated by

  perl -i -pe s/SymbolBody/Symbol/g $(git grep -l SymbolBody lld/ELF lld/COFF)

nd clang-format-diff.

Differential Revision: https://reviews.llvm.org/D39459

llvm-svn: 317370
2017-11-03 21:21:47 +00:00
George Rimar 82f0c42dad [ELF] - Teach LLD to report line numbers for data symbols.
This is PR34826.

Currently LLD is unable to report line number when reporting
duplicate declaration of some variable.

That happens because for extracting line information we always use
.debug_line section content which describes mapping from machine
instructions to source file locations, what does not help for
variables as does not describe them.

In this patch I am taking the approproate information about
variables locations from the .debug_info section.

Differential revision: https://reviews.llvm.org/D38721

llvm-svn: 317080
2017-11-01 07:42:38 +00:00
Rui Ueyama 95c142e208 Revert r316305: Remove a fast lookup table from MergeInputSection.
This reverts commit r316305 because performance regression was observed.

llvm-svn: 317026
2017-10-31 19:14:06 +00:00
Rui Ueyama ea1398eeb3 Move "Assigned" bit from SectionBase to InputSectionBase.
This bit is to manage whether an input section has already been assigned
to some output section by linker scripts or not. So it logically belongs
to InputSectionBase. SectionBase is a common base class for input and
output sections, so that wasn't the right place to define the bit.

llvm-svn: 316879
2017-10-29 23:32:23 +00:00
Rui Ueyama da4d26dfa3 Initialize members not by assignment but by the member initializer list.
llvm-svn: 316876
2017-10-29 22:26:52 +00:00
Rui Ueyama d6b7a390d8 De-template elf::getObjMsg. NFC.
llvm-svn: 316732
2017-10-27 03:13:54 +00:00
Rui Ueyama 572247f22e De-template EhFrameSection. NFC.
llvm-svn: 316731
2017-10-27 03:13:39 +00:00
Rui Ueyama d5135b7e99 Remove obsolete comment.
llvm-svn: 316520
2017-10-24 21:44:43 +00:00
George Rimar f4ca4a6fa1 [ELF] - Do not collect SHT_REL[A] sections unconditionally when --gc-sections and --emit-relocs used together.
This is "Bug 34836 - --gc-sections remove relocations from --emit-relocs",

When --emit-relocs is used, LLD currently always drops SHT_REL[A] sections from
output if --gc-sections is present. Patch fixes the issue.

Differential revision: https://reviews.llvm.org/D38724

llvm-svn: 316418
2017-10-24 08:26:32 +00:00
Konstantin Zhuravlyov 70abb6e204 LLD: Fix large integer implicitly truncated to unsigned type gcc warning
This fixes gcc warning.

Change by Brian Sumner

llvm-svn: 316365
2017-10-23 19:31:31 +00:00
Rui Ueyama d96724db42 Remove a fast lookup table from MergeInputSection.
We used to have a map from section piece offsets to section pieces
as a cache for binary search. But I found that the map took quite a
large amount of memory and didn't make linking faster. So, in this
patch, I removed the map.

This patch saves 566 MiB of RAM (2.019 GiB -> 1.453 GiB) when linking
clang with debug info, and the link time is 4% faster in that test case.

Thanks for Sean Silva for pointing this out.

llvm-svn: 316305
2017-10-22 23:02:07 +00:00
Rui Ueyama 95bf509873 Assume that mergeable input sections are smaller than 4 GiB.
By assuming that mergeable input sections are smaller than 4 GiB,
lld's memory usage when linking clang with debug info drops from
2.788 GiB to 2.019 GiB (measured by valgrind, and that does not include
memory space for mmap'ed files). I think that's a reasonable assumption
given such a large RAM savings, so this patch.

According to valgrind, gold needs 3.54 GiB of RAM to do the same thing.

NB: This patch does not introduce a limitation on the size of
output sections. You can still create sections larger than 4 GiB.

llvm-svn: 316280
2017-10-21 23:20:13 +00:00
Rui Ueyama 0543343170 Use more precise type.
llvm-svn: 315426
2017-10-11 04:01:13 +00:00
Rui Ueyama ed94f36154 Remove an unused default argument.
llvm-svn: 315386
2017-10-10 23:09:23 +00:00
Rui Ueyama f987fe7869 Add more comments.
llvm-svn: 315267
2017-10-10 03:40:57 +00:00
Rui Ueyama 124bedbd50 Add comment to InputSectionBase::File.
This patch also moves declarations so that related declarations next
to each other.

llvm-svn: 315266
2017-10-10 03:22:29 +00:00
Rui Ueyama 339ddd1685 Remove dead function.
llvm-svn: 315265
2017-10-10 03:01:41 +00:00
Rui Ueyama e8936bca72 Add comment.
llvm-svn: 315163
2017-10-08 01:55:29 +00:00
Rui Ueyama 10f5867135 Remove redundant initialization code.
llvm-svn: 315158
2017-10-08 00:45:34 +00:00
Rui Ueyama e41f9e0651 Inline a small function. NFC.
llvm-svn: 315096
2017-10-06 20:08:51 +00:00
Shoaib Meenai 50d7b36f5e [ELF] Decompress debug info sections early
When reporting a symbol conflict, LLD parses the debug info to report
source location information. Sections have not been decompressed at this
point, so if an object file contains zlib compressed debug info, LLD
ends up passing this compressed debug info to the DWARF parser, which
causes debug info parsing failures and can trigger assertions in the
parser (as the test case demonstrates).

Decompress debug sections when constructing the LLDDwarfObj to avoid
this issue. This doesn't handle GNU-style compressed debug info sections
(.zdebug_*), which at present are simply ignored by LLDDwarfObj; those
can be done in a follow-up.

Differential Revision: https://reviews.llvm.org/D38491

llvm-svn: 314866
2017-10-04 00:19:41 +00:00
Rui Ueyama 3f851704c1 Move new lld's code to Common subdirectory.
New lld's files are spread under lib subdirectory, and it isn't easy
to find which files are actually maintained. This patch moves maintained
files to Common subdirectory.

Differential Revision: https://reviews.llvm.org/D37645

llvm-svn: 314719
2017-10-02 21:00:41 +00:00
Rui Ueyama abf908e632 Fix a data race found by tsan.
Reads from `Live` and writes to `OutputOff` in the following code race
even though they are logically independent because they are bitfields
sharing the same word.

  for (size_t I = 0, E = Sec->Pieces.size(); I != E; ++I) {
    if (!Sec->Pieces[I].Live)
      continue;
    CachedHashStringRef Str = Sec->getData(I);
    size_t ShardId = getShardId(Str.hash());
    if ((ShardId & (Concurrency - 1)) == ThreadId)
      Sec->Pieces[I].OutputOff = Shards[ShardId].add(Str);
  }

llvm-svn: 314711
2017-10-02 20:16:13 +00:00
Rui Ueyama 43ca7167ad Inline hot functions.
llvm-svn: 314637
2017-10-01 23:46:31 +00:00
NAKAMURA Takumi 169dbde262 Revert rL313697, "Compact EhSectionPiece from 32 bytes to 16 bytes."
It broke selfhosting.
http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/4896

llvm-svn: 313731
2017-09-20 08:03:18 +00:00
Rui Ueyama 014b0f24ae Compact EhSectionPiece from 32 bytes to 16 bytes.
EhSectionPiece used to have a pointer to a section, but that pointer was
mostly redundant because we almost always know what the section is without
using that pointer. This patch removes the pointer from the struct.

This patch also use uint32_t/int32_t instead of size_t to represent
offsets that are hardly be larger than 4 GiB. At the moment, I think it is
OK even if we cannot handle .eh_frame sections larger than 4 GiB.

Differential Revision: https://reviews.llvm.org/D38012

llvm-svn: 313697
2017-09-19 23:36:48 +00:00
George Rimar 696a7f9ac6 [ELF] - Introduce std::vector<InputFile *> global arrays.
This patch removes lot of static Instances arrays from different input file 
classes and introduces global arrays for access instead. Similar to arrays we
have for InputSections/OutputSectionCommands.

It allows to iterate over input files in a non-templated code.

Differential revision: https://reviews.llvm.org/D35987

llvm-svn: 313619
2017-09-19 09:20:54 +00:00
Rui Ueyama 34a0dd5283 Rename EhSectionPiece::ID -> EhSectionPiece::Sec.
ID sounds like an identifier, but this is actually a pointer to a section.

llvm-svn: 313588
2017-09-18 23:07:33 +00:00
Rui Ueyama e084aac123 Do not use inheritance for EhSectionPiece.
EhSectionPiece inherited from SectionPiece, but we did not actually use
EhSectionPiece objects as SectionPiece ojbects. They were handled as
distinct types. So it didn't make much sense to use inheritance.

llvm-svn: 313587
2017-09-18 23:07:21 +00:00
Rui Ueyama a6ff617967 Remove useless accessor.
llvm-svn: 313586
2017-09-18 23:07:09 +00:00
Rafael Espindola 17e93d28f2 Simplify type. NFC.
llvm-svn: 312675
2017-09-06 22:16:32 +00:00
Rui Ueyama 314a005002 Remove a lock and use a std::unique_ptr instead.
We had a lock to guard BAlloc from being used concurrently, but that
is not very easy to understand. This patch replaces it with a
std::unique_ptr.

llvm-svn: 311056
2017-08-17 00:27:55 +00:00
George Rimar d6bcde389a [ELF] - Fix "--symbol-ordering-file doesn't work with linker scripts"
This is PR33889,

Patch adds support of combination of linkerscript and
-symbol-ordering-file option.

If no sorting commands are present in script inside section declaration
and no --sort-section option specified, code uses sorting from ordering 
file if any exist.

Differential revision: https://reviews.llvm.org/D35843

llvm-svn: 310045
2017-08-04 10:25:29 +00:00