Commit Graph

458 Commits

Author SHA1 Message Date
Simon Atanasyan
85c6b44817 [ELF][MIPS] Support .MIPS.abiflags section
This section supersedes .reginfo and .MIPS.options sections. But for now
we have to support all three sections for ABI transition period.

llvm-svn: 278482
2016-08-12 06:28:49 +00:00
Rui Ueyama
bdf836db1b Simplify output section ownership management.
One reason why we are (ab)using OutputSectionFactory class is
because it owns output sections. Technically there's no need
to have it own sections. So, this patch transfers the ownership
to Out<ELFT>.

llvm-svn: 278452
2016-08-12 01:10:17 +00:00
Eugene Leviant
ceabe80e97 [ELF] Symbol assignment within output section description
llvm-svn: 278322
2016-08-11 07:56:43 +00:00
George Rimar
16a5930803 [ELF] - Removed dead code. NFC.
llvm-svn: 278115
2016-08-09 10:57:42 +00:00
Rui Ueyama
1034c9e342 Remove isOutputDynamic and use Out<ELFT>::DynSymTab instead.
This patch is to not instantiate DynSymTab and DynStrTab if the
output is not a dynamic output.

llvm-svn: 278095
2016-08-09 04:42:01 +00:00
Rui Ueyama
cbd434a6c4 Remove redundant variable.
llvm-svn: 278094
2016-08-09 04:31:21 +00:00
Rui Ueyama
a8f6feaa1a Separate {Preinit,Init,Fini}Arrays from Out<ELFT>::Dynamic.
Even if an output is not a dynamic object, the output may have
.{preinit,init,fini} sections. Therefore, managing these sections
as Out<ELFT>::Dynamic's members is not correct.

llvm-svn: 278093
2016-08-09 04:25:20 +00:00
Rui Ueyama
0778490428 Remove DefinedCommon::Section.
Since CommonInputSection is a singleton class, we don't need
to store pointers to all DefinedCommon symbols.

llvm-svn: 277410
2016-08-02 01:35:13 +00:00
Eugene Leviant
3e6b027705 [ELF] Allows setting section for common symbols in linker script
llvm-svn: 277023
2016-07-28 19:24:13 +00:00
Rafael Espindola
0b113671c5 Make toPhdrFlags a member function. NFC.
llvm-svn: 276868
2016-07-27 14:10:56 +00:00
Rafael Espindola
2deeb6093d Fix PR28575.
Not all relocations from a .eh_frame that point to an executable
section should be ignored. In particular, the relocation finding the
personality function should not.

This is a reduction from trying to bootstrap a static lld on linux.

llvm-svn: 276329
2016-07-21 20:18:30 +00:00
Rafael Espindola
0f7cedaa1e Create thunks before regular relocation scan.
We will need to do something like this to support range extension
thunks since that process is iterative.

Doing this also has the advantage that when doing the regular
relocation scan the offset in the output section is known and we can
just store that. This reduces the number of times we have to run
getOffset and I think will allow a more specialized .eh_frame
representation.

By itself this is already a performance win.

firefox
  master 7.295045737
  patch  7.209466989 0.98826892235
chromium
  master 4.531254468
  patch  4.509221804 0.995137623774
chromium fast
  master 1.836928973
  patch  1.823805241 0.992855612714
the gold plugin
  master 0.379768791
  patch  0.380043405 1.00072310839
clang
  master 0.642698284
  patch  0.642215663 0.999249070657
llvm-as
  master 0.036665467
  patch  0.036456225 0.994293213284
the gold plugin fsds
  master 0.40395817
  patch  0.404384555 1.0010555177
clang fsds
  master 0.722045545
  patch  0.720946135 0.998477367518
llvm-as fsds
  master 0.03292646
  patch  0.032759965 0.994943428477
scylla
  master 3.427376378
  patch  3.368316181 0.98276810292

llvm-svn: 276146
2016-07-20 17:58:07 +00:00
Rui Ueyama
a7f7884df8 Simplify output section ownership.
This patch simplifies output section management by making
Factory class have ownership of sections that creates.

Differential Revision: https://reviews.llvm.org/D22575

llvm-svn: 276141
2016-07-20 17:19:03 +00:00
Rui Ueyama
e33579072d Remove SymbolBody::PlaceholderKind.
In the last patch for --trace-symbol, I introduced a new symbol type
PlaceholderKind and store it to SymVector storage. It made all code
that iterates over SymVector to recognize and skip PlaceholderKind
symbols. I found that that's annoying.

In this patch, I removed PlaceholderKind and stop storing them to SymVector.
Now the information whether a symbol is being watched by --trace-symbol
is stored to the Symtab hash table.

llvm-svn: 275747
2016-07-18 01:35:00 +00:00
Rui Ueyama
69c778c084 Implement almost-zero-cost --trace-symbol.
--trace-symbol is a command line option to watch a symbol.
Previosly, we looked up a hash table for a new symbol if the
option is given. Any code that looks up a hash table for each
symbol is expensive because the linker handles a lot of symbols.
In our design, we look up a hash table strictly only once
for a symbol, so --trace-symbol was an exception.

This patch improves efficiency of the option by merging the
hash table into the symbol table.

Instead of looking up a separate hash table with a string,
this patch sets `Traced` flag to symbols specified by --trace-symbol.
So, if you insert a symbol and get a symbol with `Traced` flag on,
you know that you need to print out a log message for the symbol.
This is nearly zero cost.

llvm-svn: 275716
2016-07-17 17:50:09 +00:00
Rui Ueyama
434b56179e Add a pointer to a source file to SymbolBody.
Previously, each subclass of SymbolBody had a pointer to a source
file from which it was created. So, there was no single way to get
a source file for a symbol. We had getSourceFile<ELFT>(), but the
function was a bit inconvenient as it's a template.

This patch makes SymbolBody have a pointer to a source file.
If a symbol is not created from a file, the pointer has a nullptr.

llvm-svn: 275701
2016-07-17 03:11:46 +00:00
Rui Ueyama
818bb2f8dc Remove redundant namespace specifiers.
llvm-svn: 275694
2016-07-16 18:55:47 +00:00
Rui Ueyama
af469d47e9 Rename SymbolVersions VersionDefinitions.
SymbolVersions sounds like it had versions for a symbol, so rename it.

llvm-svn: 275674
2016-07-16 04:09:27 +00:00
Rui Ueyama
bc94dd9b28 Rename Version VersionDefinition.
The identifier `Version` was used too often in the code to handle
symbol versions. The struct that contains version definitions is
named `Version`. Local variables for version ID are named `Version`.
Local varaible for version string are named `Version`.

This patch give them different names.

llvm-svn: 275673
2016-07-16 04:02:00 +00:00
Rui Ueyama
e9381bd2d8 Remove redundant variable.
llvm-svn: 275667
2016-07-16 02:47:42 +00:00
Rui Ueyama
f524464e2f Set sh_addralign in the constructor for consistency. NFC.
llvm-svn: 275666
2016-07-16 02:36:00 +00:00
Rui Ueyama
9f61964769 Make Verdef and Verdaux adjacent in the version definition section.
Previously, Verdefs and Verdauxs are separated in the section.
The new layout is easier to write as we do not have to maintain
two pointers and can avoid passing a reference to a pointer.

llvm-svn: 275665
2016-07-16 02:29:45 +00:00
Rui Ueyama
0ff953e811 Use SymbolVersion::Id instead of a hard-coded local variable.
llvm-svn: 275660
2016-07-16 02:00:43 +00:00
Rui Ueyama
cafc0f2e03 Set DT_MIPS_BASE_ADDRESS correctly if -image-base is given.
Differential Revision: http://reviews.llvm.org/D22323

llvm-svn: 275446
2016-07-14 17:40:18 +00:00
Rui Ueyama
3b04d833c4 Set sh_addralign to 1 instead of 0.
ELF spec says that alignment of 0 is equivalent to 1.
Previously, we arbitrary set to 0 or 1, but always setting to 1
makes our program simpler.

llvm-svn: 275374
2016-07-14 05:46:24 +00:00
Rui Ueyama
803b120ba1 Add GotEntrySize/GotPltEntrySize to ELF target.
Patch by H.J Lu.

For x86-64 psABI, the entry size of .got and .got.plt sections is 8
bytes for both LP64 and ILP32.  Add GotEntrySize and GotPltEntrySize
to ELF target instead of using size of ELFT::uint.  Now we can generate
a simple working x32 executable.

Differential Revision: http://reviews.llvm.org/D22288

llvm-svn: 275301
2016-07-13 18:55:14 +00:00
Rui Ueyama
484a49514f Rename VAStart -> ImageBase. NFC.
Config members are named after corresponding command line options.
This patch renames VAStart ImageBase so that they are in line with
--image-base.

Differential Revision: http://reviews.llvm.org/D22277

llvm-svn: 275298
2016-07-13 18:40:59 +00:00
George Rimar
6892afaa2d Recommit r275161 "[ELF] - Move section factory out from writer to make it reusable."
With fix:
* fixed compilation error under linux:

template <class ELFT> class OutputSectionFactory {
...
  typedef typename SectionKey<ELFT::Is64Bits> Key;

changed to:
template <class ELFT> class OutputSectionFactory {
...
  typedef typename elf::SectionKey<ELFT::Is64Bits> Key;

llvm-svn: 275166
2016-07-12 09:49:43 +00:00
George Rimar
d8f547fab4 Revert r275161 "[ELF] - Move section factory out from writer to make it reusable."
It broke build bot:
http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-debian-fast/builds/39652

llvm-svn: 275163
2016-07-12 09:11:13 +00:00
George Rimar
e51f7f4d39 [ELF] - Move section factory out from writer to make it reusable.
Since linkerscript should create sections by itself
(if SECTIONS command is present),
then we might want to reuse the OutputSectionFactory (D19976 already do that now),
so this patch moves it out from writer cpp file for that purpose.

Differential revision: http://reviews.llvm.org/D19977

llvm-svn: 275161
2016-07-12 08:38:04 +00:00
Davide Italiano
f8591cf249 [gardening] Switch back to auto. NFCI.
Pointed out by: Rui Ueyama.

llvm-svn: 274643
2016-07-06 17:41:55 +00:00
Davide Italiano
b4b68b64fd [OutputSection] Work around GCC not being able to deduce auto.
The build otherwise fails with:
[ 39%] Building CXX object
tools/lld/ELF/CMakeFiles/lldELF.dir/OutputSections.cpp.o
/export/gnu/import/git/llvm/tools/lld/ELF/OutputSections.cpp: In
member function ‘void
lld::elf::GnuHashTableSection<ELFT>::addSymbols(std::vector<std::pair<lld::elf::SymbolBody*,
long unsigned int> >&)’:
/export/gnu/import/git/llvm/tools/lld/ELF/OutputSections.cpp:585:8:
error: inconsistent deduction for ‘auto’: ‘auto’ and then
‘__gnu_cxx::__normal_iterator<std::pair<lld::elf::SymbolBody*, long
unsigned int>*, std::vector<std::pair<lld::elf::SymbolBody*, long
unsigned int> > >’

Reported by:  H. J. Liu

llvm-svn: 274518
2016-07-04 19:49:55 +00:00
George Rimar
33b9de4b32 [ELF] - Depricate version references.
This is PR28358

According to
https://www.akkadia.org/drepper/dsohowto.pdf

"The fourth point, the VERS 1.0 version being referred to in the VERS 2.0 definition, is not really important in symbol versioning. It marks the predecessor relationship of the two versions and it is done to maintain the similar- ities with Solaris’ internal versioning. It does not cause any problem it might in fact be useful to a human reader so predecessors should always be mentioned."

Patch partially reverts 273423 "[ELF] - Implemented version script hierarchies.",
version references are just ignored now.

Differential revision: http://reviews.llvm.org/D21888

llvm-svn: 274345
2016-07-01 11:45:10 +00:00
Rui Ueyama
fbbde548cf Move isValidCIdentifier to Strings.cpp.
llvm-svn: 274112
2016-06-29 09:08:02 +00:00
Simon Atanasyan
002e244717 [ELF][MIPS] Support MIPS TLS relocations
The patch adds one more partition to the MIPS GOT. This time it is for
TLS related GOT entries. Such entries are located after 'local' and 'global'
ones. We cannot get a final offset for these entries at the time of
creation because we do not know size of 'local' and 'global' partitions.
So we have to adjust the offset later using `getMipsTlsOffset()` method.

All MIPS TLS relocations which need GOT entries operates MIPS style GOT
offset - 'offset from the GOT's beginning' - MipsGPOffset constant. That
is why I add new types of relocation expressions.

One more difference from othe ABIs is that the MIPS ABI does not support
any TLS relocation relaxations. I decided to make a separate function
`handleMipsTlsRelocation` and put MIPS TLS relocation handling code
there. It is similar to `handleTlsRelocation` routine and duplicates its
code. But it allows to make the code cleaner and prevent pollution of
the `handleTlsRelocation` by MIPS 'if' statements.

Differential Revision: http://reviews.llvm.org/D21606

llvm-svn: 273569
2016-06-23 15:26:31 +00:00
Rui Ueyama
809d8e2d41 Fix a bug that MIPS thunks can overwrite other section contents.
Peter Smith found while trying to support thunk creation for ARM that
LLD sometimes creates broken thunks for MIPS. The cause of the bug is
that we assign file offsets to input sections too early. We need to
create all sections and then assign section offsets because appending
thunks changes file offsets for all following sections.

This patch separates the pass to assign file offsets from thunk
creation pass. This effectively reverts r265673.

Differential Revision: http://reviews.llvm.org/D21598

llvm-svn: 273532
2016-06-23 04:33:42 +00:00
George Rimar
0ab48b7334 [ELF] - Implemented version script hierarchies.
Patch implements hierarchies for version scripts. 
This allows to handle script files with dependencies, like next one has:

LIBSAMPLE_1.0{
  global:
  a;
};

LIBSAMPLE_2.0
{
  global:
  b;
}LIBSAMPLE_1.0;

Differential revision: http://reviews.llvm.org/D21556

llvm-svn: 273423
2016-06-22 14:40:45 +00:00
George Rimar
d3566309eb [ELF] - Recommit r273143("[ELF] - Basic versioned symbols support implemented.")
With fix:
-soname flag was not set in testcase. Hash calculated for base def was different on local
and bot machines because filename fos used for calculating.

Initial commit message:
Patch implements basic support of versioned symbols.
There is no wildcards patterns matching except local: *;
There is no support for hierarchies.
There is no support for symbols overrides (@ vs @@ not handled).

This patch allows programs that using simple scripts to link and run.

Differential revision: http://reviews.llvm.org/D21018

llvm-svn: 273152
2016-06-20 11:55:12 +00:00
Simon Atanasyan
7b8481bf95 [ELF][MIPS] Fix predicate used for sorting MIPS dynamic symbol tables
Now it conforms requirement for std::stable_sort predicates. That
resolves build-bot failures on Windows hosts.

llvm-svn: 273151
2016-06-20 11:37:56 +00:00
George Rimar
d03f97211a Revert r273143 "[ELF] - Basic versioned symbols support implemented."
It broke buildbot:
http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast

llvm-svn: 273146
2016-06-20 10:29:53 +00:00
George Rimar
c31fee2212 [ELF] - Basic versioned symbols support implemented.
Patch implements basic support of versioned symbols.
There is no wildcards patterns matching except local: *;
There is no support for hierarchies.
There is no support for symbols overrides (@ vs @@ not handled).

This patch allows programs that using simple scripts to link and run.

Differential revision: http://reviews.llvm.org/D21018

llvm-svn: 273143
2016-06-20 10:16:33 +00:00
George Rimar
06e930d37a Fixed compilation error under MSVS 2015 (looks like compiler bug). NFC.
llvm-svn: 273142
2016-06-20 10:01:50 +00:00
Simon Atanasyan
4132511cdc [ELF][MIPS] Support GOT entries for non-preemptible symbols with different addends
There are two motivations for this patch. The first one is a preparation
for support MIPS TLS relocations. It might sound like a joke but for GOT
entries related to TLS relocations MIPS ABI uses almost regular approach
with creation of dynamic relocations for each GOT enty etc. But we need
to separate these 'regular' TLS related entries from MIPS specific local
and global parts of GOT. ABI declare simple solution - all TLS related
entries allocated at the end of GOT after local/global parts. The second
motivation it to support GOT relocations for non-preemptible symbols
with addends. If we have more than one GOT relocations against symbol S
with different addends we need to create GOT entries for each unique
Symbol/Addend pairs.

So we store all MIPS GOT entries in separate containers. For non-preemptible
symbols we have to maintain two data structures. The first one is MipsLocal
vector. Each entry corresponds to the GOT entry from the 'local' part
of the GOT contains the symbol's address plus addend. The second one
is MipsLocalMap. It is a map from Symbol/Addend pair to the GOT index.

Differential Revision: http://reviews.llvm.org/D21297

llvm-svn: 273127
2016-06-19 21:39:37 +00:00
Rui Ueyama
424b408165 Rename Align -> Alignment.
I think it is me who named these variables, but I always find that
they are slightly confusing because align is a verb.
Adding four letters is worth it.

llvm-svn: 272984
2016-06-17 01:18:46 +00:00
Rui Ueyama
4a90f57ef2 Rename PltZero -> PltHeader.
PltZero (or PLT[0]) was an appropriate name for the little code
we have at beginning of the PLT section when we only supported x86
since the code for x86 just fits in the first PLT slot.

It's not the case anymore. The code for ARM64 occupies first two
slots, so PltZero spans PLT[0] and PLT[1], for example.
This patch renames it to avoid confusion.

llvm-svn: 272913
2016-06-16 16:28:50 +00:00
Rui Ueyama
c9fee5fee6 Eliminate unnecessary call of SymbolBody::getPltVA.
For ARM and MIPS, we don't need to call this function.
This patch passes a symbol instead of a PLT entry address
so that the target handler can call it if necessary.

llvm-svn: 272910
2016-06-16 16:14:50 +00:00
Simon Atanasyan
311b4b15e1 [ELF][MIPS] Move MIPS specific code under if block to accent its specificity. NFC
llvm-svn: 272389
2016-06-10 12:26:28 +00:00
Rafael Espindola
a8777c2ef8 Handle gd tls relocs pointing to local symbols.
If the symbol is local we don't need to create a R_X86_64_DTPOFF64, we
can just write the correct value in the got.

Should fix pr28018.

llvm-svn: 272205
2016-06-08 21:31:59 +00:00
George Rimar
71a0a40b97 [ELF] - Removed includeInGnuHashTable() function. NFC.
It was one line global static function that looks nicer to inline,
patch do that.

llvm-svn: 272137
2016-06-08 12:57:14 +00:00
George Rimar
56efb34901 [ELF] - Replaced one more hardcode with named constant. NFC.
llvm-svn: 272130
2016-06-08 11:49:01 +00:00