Commit Graph

3859 Commits

Author SHA1 Message Date
Rafael Espindola a7a945a13b Rename one of the variables to avoid confusion.
llvm-svn: 301691
2017-04-28 21:23:43 +00:00
Rui Ueyama 3012b371fd Change the format of the map file.
Previously, we printed out input sections and input files in
separate columns as shown below.

  Address          Size             Align Out     In      File    Symbol
  0000000000201000 0000000000000015     4 .text
  0000000000201000 000000000000000e     4         .text
  0000000000201000 000000000000000e     4                 foo.o
  0000000000201000 0000000000000000     0                         _start
  0000000000201005 0000000000000000     0                         f(int)
  000000000020100e 0000000000000000     0                         local
  0000000000201010 0000000000000002     4                 bar.o
  0000000000201010 0000000000000000     0                         foo
  0000000000201011 0000000000000000     0                         bar

This format doesn't make much sense because for each input section,
there's always exactly one input file. This patch changes the format
to this.

  Address          Size             Align Out     In      Symbol
  0000000000201000 0000000000000015     4 .text
  0000000000201000 000000000000000e     4         foo.o:(.text)
  0000000000201000 0000000000000000     0                 _start
  0000000000201005 0000000000000000     0                 f(int)
  000000000020100e 0000000000000000     0                 local
  0000000000201010 0000000000000002     4         bar.o:(.text)
  0000000000201010 0000000000000000     0                 foo
  0000000000201011 0000000000000000     0                 bar

Differential Revision: https://reviews.llvm.org/D32657

llvm-svn: 301683
2017-04-28 20:38:27 +00:00
Rafael Espindola b3bc1ed0d4 Remove LinkerScript::flush.
This patch replaces flush with a last ditch attempt at synchronizing
the section list with the linker script "AST".

The synchronization is a bit of a hack and should in time be avoided
by creating the AST earlier so that modifications can be made directly
to it instead of modifying the section list and synchronizing it back.

This is the main step for fixing
https://bugs.llvm.org/show_bug.cgi?id=32816. With this in place I
think the only missing thing would be to have processCommands assign
section indexes as dummy offsets so that the sort in
OutputSection::finalize works.

With this LinkerScript::assignAddresses becomes much simpler, which
should help with the thunk work.

llvm-svn: 301678
2017-04-28 20:22:47 +00:00
Rui Ueyama 8a3ef95fc9 Use toString(Inputfile*) to format a file object.
llvm-svn: 301674
2017-04-28 20:00:09 +00:00
Rui Ueyama 72408fb2ac Remove trailing whitespace from the -Map output.
If a string is shorter than 7 characters, we used to print out
trailing whitespace characters.

llvm-svn: 301668
2017-04-28 18:54:08 +00:00
Rui Ueyama 2634d0ff5c Remove a redundant local variable.
llvm-svn: 301661
2017-04-28 17:50:23 +00:00
Rui Ueyama b882e5910d Speed up the -Map option.
We found that some part of code for the -Map option takes O(m*n)
where m is the number of input sections in some file and n is
the number of symbols in the same file. If you do LTO, we usually
have only a few object files as inputs for the -Map option
feature, so this performance characteristic was worse than I
expected.

This patch rewrites the -Map option feature to speed it up.
I eliminated the O(m*n) bottleneck and also used multi-threading.

As a result, clang link time with the -Map option improved from
18.7 seconds to 11.2 seconds. Without -Map, it takes 7.7 seconds,
so the -Map option is now about 3x faster than before for this
test case (from 11.0 seconds to 3.5 seconds.) The generated output
file size was 223 MiB, and the file contains 1.2M lines.

Differential Revision: https://reviews.llvm.org/D32631

llvm-svn: 301659
2017-04-28 17:19:13 +00:00
Rui Ueyama 42fca6e794 Recommend users use readelf instead of objdump to dump .comment contents.
readelf's output is much easier to read than objdump's as you can see below.

  $ readelf --string-dump .comment foo
  String dump of section '.comment':
    [     1]  GCC: (Ubuntu 4.8.4-2ubuntu1~14.04.3) 4.8.4
    [    2c]  clang version 5.0.0
    [    41]  Linker: LLD 5.0.0

  $ objdump -j .comment -s foo
  Contents of section .comment:
   0000 00474343 3a202855 62756e74 7520342e  .GCC: (Ubuntu 4.
   0010 382e342d 32756275 6e747531 7e31342e  8.4-2ubuntu1~14.
   0020 30342e33 2920342e 382e3400 636c616e  04.3) 4.8.4.clan
   0030 67207665 7273696f 6e20352e 302e3020  g version 5.0.0
   0040 004c696e 6b65723a 204c4c44 20352e30  .Linker: LLD 5.0
   0050 2e3000                               .0.

llvm-svn: 301515
2017-04-27 04:50:08 +00:00
Rui Ueyama c9d82b9e16 Simplify BinaryFile::parse and add comments.
llvm-svn: 301514
2017-04-27 04:01:36 +00:00
Rui Ueyama 63d48e5956 Remove needless type conversions.
llvm-svn: 301513
2017-04-27 04:01:14 +00:00
Rui Ueyama e5ad2986fc Remove unnecessary instantiation of StringRef.
SoName's type has changed from StringRef to std::string, so this
code does not make sense anymore.

llvm-svn: 301490
2017-04-26 23:00:32 +00:00
Rui Ueyama 330e52b018 Removes createELFFile which takes a template class as a template parameter.
This patch is to reduce amount of template uses. The new code is less
exciting and boring than before, but I think it is easier to read.

Differential Revision: https://reviews.llvm.org/D32467

llvm-svn: 301488
2017-04-26 22:51:51 +00:00
Rafael Espindola 4f013bb3b2 Create an OutputSection for each non-empty OutputSectionCommand.
We were already pretty close, the one exception was when a name was
reused in another SECTIONS directive:

SECTIONS {
  .text : { *(.text) }
  .data : { *(.data) }
}
SECTIONS {
  .data : { *(other) }
}

In this case we would create a single .data and magically output
"other" while looking at the first OutputSectionCommand.

We now create two .data sections. This matches what gold does. If we
really want to create a single one, we should change the parser so that
the above is parsed as if the user had written

SECTIONS {
  .text : { *(.text) }
  .data : { *(.data) *(other)}
}

That is, there should be only one OutputSectionCommand for .data and
it would have two InputSectionDescriptions.

By itself this patch makes the code a bit more complicated, but is an
important step in allowing assignAddresses to operate just on the
linker script.

llvm-svn: 301484
2017-04-26 22:30:15 +00:00
Rui Ueyama cf8247ef48 Do flag compatibility check in checkOptions. NFC.
llvm-svn: 301476
2017-04-26 21:27:33 +00:00
Rui Ueyama 08af54c304 Factor out code to parse -build-id. NFC.
llvm-svn: 301475
2017-04-26 21:23:11 +00:00
Rui Ueyama d283eb7091 Make LLD work even if the current directory is not writable.
llvm-svn: 301423
2017-04-26 16:15:07 +00:00
Rui Ueyama 7163027884 Move code to emit error messages from Filesystem.cpp to Driver.cpp.
isFileWritable() checked if a file is writable and then emitted
an error message if it is not writable. So it did more than the
name says. This patch moves error() calls to Driver.

llvm-svn: 301422
2017-04-26 16:14:46 +00:00
George Rimar 3505716d72 [ELF] - Remove dead TLS relocations relative code for MIPS and ARM
This code was not used because of
handleARMTlsRelocation and handleMipsTlsRelocation methods that are called
for these platforms instead of regular TLS code.

Differential revision: https://reviews.llvm.org/D32355

llvm-svn: 301414
2017-04-26 14:48:36 +00:00
George Rimar 9703ad2221 [ELF] - Implemented --defsym option.
gnu ld description of option is:

--defsym=symbol=expression
Create a global symbol in the output file, containing the absolute address given 
by expression. You may use this option as many times as necessary to define multiple
symbols in the command line. A limited form of arithmetic is supported for the 
expression in this context: you may give a hexadecimal constant or the name of an
existing symbol, or use "+" and "-" to add or subtract hexadecimal constants or 
symbols. If you need more elaborate expressions, consider using the linker command
language from a script. Note: there should be no white space between symbol, 
the equals sign ("="), and expression.

In compare with D32082, this patch does not support math expressions and absolute
symbols. It implemented via code similar to --wrap. That covers 1 of 3 possible
--defsym cases.

Differential revision: https://reviews.llvm.org/D32171

llvm-svn: 301391
2017-04-26 10:40:02 +00:00
Rui Ueyama 8d817f27e6 Make it explicit that -export-dynamic overrides -dynamic-list and -export-dynamic-symbol.
No functionality change.

llvm-svn: 301336
2017-04-25 17:40:12 +00:00
Rui Ueyama 577168ecde [ELF] Improve error message for incompatible section flags
Previously we were not printing out the flags of the incompatible
section which made it difficult to determine what the problem was.

The error message format has been change to the following:

  error: incompatible section flags for .bar
  >>> /foo/bar/incompatible-section-flags.s.tmp.o:(.bar): 0x403
  >>> output section .bar: 0x3

Patch by Alexander Richardson.

Differential Revision: https://reviews.llvm.org/D32484

llvm-svn: 301319
2017-04-25 16:00:44 +00:00
Rui Ueyama a2a46a9532 Define __tls_get_addr as a hidden symbol even for ARM or MIPS.
addIgnored defines a given symbol even if there is no existing
symbol with the same name. So, even if libc provides __tls_get_addr,
we should still be able to call addIgnored.

Differential Revision: https://reviews.llvm.org/D32053

llvm-svn: 301290
2017-04-25 04:44:54 +00:00
Rui Ueyama 321b9cd072 Export __progname even if a -dynamic-list is given.
BSD's __progname symbol is defined in crt1.o and linked against main
executables. The libc expects that main executables export __progname
symbol via .dynsym sections. In order to handle this case, we scan
undefined symbols in DSOs and exported them by setting Sym->ExportDynamic
to true.

But it turned out that setting that variable is not enough to make sure
that symbols are exported in all use cases. If a -dynamic-list option is
given, all symbols not explicitly mentioned in a version script are
hidden by default. That hides __progname symbol. This patch fixes the issue.

Fixes https://bugs.llvm.org/show_bug.cgi?id=32703

llvm-svn: 301282
2017-04-25 00:15:48 +00:00
Rui Ueyama 273bbbc3a7 Remove a useless temporary variable.
llvm-svn: 301278
2017-04-24 23:50:58 +00:00
Rafael Espindola 3460cdd440 Remove DefaultSoName.
We can just use the existing SoName member variable. It now initially
contains what was in DefaultSoName and is modified if the .so has an
actual soname.

llvm-svn: 301259
2017-04-24 21:44:20 +00:00
Shoaib Meenai b573b4b04d [ELF] Account for R_386_TLS_LDO_32 addend
This relocation type has an implicit addend. Account for it when
processing the relocation. Add an offset to an existing test to ensure
it gets processed correctly.

Fixes PR32634.

Differential Revision: https://reviews.llvm.org/D32336

llvm-svn: 301207
2017-04-24 18:02:11 +00:00
Peter Smith cbfe9e946f [ELF] Always use Script::assignAddresses()
This change fabricates linker script commands for the case where there is
no linker script SECTIONS to control address assignment. This permits us
to have a single Script->assignAddresses() function.
    
There is a small change in user-visible-behavior with respect to the
handling of .tbss SHT_NOBITS, SHF_TLS as the Script->assignAddresses()
requires setDot() to be called with monotically increasing addresses.
The tls-offset.s test has been updated so that the script and non-script
results match.

This change should make the non-script behavior of lld closer to an
equivalent linker script.

Differential Revision: https://reviews.llvm.org/D31888

llvm-svn: 300687
2017-04-19 12:46:32 +00:00
Rui Ueyama 196adecc3a Fix buildbot failure.
llvm-svn: 300681
2017-04-19 11:58:59 +00:00
Rui Ueyama 29181007df Update comment.
llvm-svn: 300676
2017-04-19 11:32:27 +00:00
Rui Ueyama 07c62c1174 Rename CompressedHeader ZDebugHeader.
`CompressedHeader` is a header for compressed data, and the header
itself is not compressed. So the previous name was confusing.

llvm-svn: 300675
2017-04-19 11:32:13 +00:00
Rui Ueyama 066c4ab9fe Simplify createHeader and inline it.
createHeader didn't use data members of Elf_Chdr type and write
directly to a given buffer. That is not a good practice because
the function had a knowledge of the struct layout.

llvm-svn: 300674
2017-04-19 11:31:58 +00:00
Rui Ueyama 4627873807 Fallthrough to reduce code a bit. NFC.
llvm-svn: 300673
2017-04-19 11:31:45 +00:00
George Rimar dbf9339715 [ELF] - Implemented --compress-debug-sections option.
Patch implements --compress-debug-sections=zlib.

In compare with D20211 (a year old patch, abandoned), it implementation
uses streaming and fully reimplemented, does not support zlib-gnu for
simplification.

This is PR32308.

Differential revision: https://reviews.llvm.org/D31941

llvm-svn: 300444
2017-04-17 08:58:12 +00:00
Rui Ueyama 3a16769e04 [ELF] Remove unused member [NFC]
Patch by Alexander Richardson.

Differential Revision: https://reviews.llvm.org/D32077

llvm-svn: 300359
2017-04-14 18:38:38 +00:00
George Rimar 1022112d77 [ELF] - Linkerscript: make section with no content to be SHT_PROGBITS by default.
Imagine next script:

SECTIONS { BYTE(0x11); }

Section content written to disk will be 0x11. Previous LLD behavior was to make this
section SHT_NOBITS. What is not correct because section has content.
ld.bfd makes such sections SHT_PROGBITS, this patch do the same.

This fixes PR32537

Differential revision: https://reviews.llvm.org/D32016

llvm-svn: 300317
2017-04-14 09:37:00 +00:00
George Rimar 01aa795f82 [ELF] LinkerScript: Don't assign zero to all regular symbols
This fixes an assertion `Align != 0u && "Align can't be 0."'
in llvm::alignTo() when a linker script references a globally
defined variable in an ALIGN() context.

Patch by Alexander Richardson !

Differential revision: https://reviews.llvm.org/D31984

llvm-svn: 300315
2017-04-14 09:23:26 +00:00
Peter Collingbourne 8446f1fe6a Object, LTO: Add target triple to irsymtab and LTO API.
Start using it in LLD to avoid needing to read bitcode again just to get the
target triple, and in llvm-lto2 to avoid printing symbol table information
that is inappropriate for the target.

Differential Revision: https://reviews.llvm.org/D32038

llvm-svn: 300300
2017-04-14 02:55:06 +00:00
Peter Collingbourne c0987938ea ELF: Remove some dead code.
llvm-svn: 300297
2017-04-14 02:34:32 +00:00
Rui Ueyama 0faa53aaab Remove useless local variable.
llvm-svn: 300294
2017-04-14 01:35:04 +00:00
Rui Ueyama c49bdd6d5d Replace uintX_t with uint64_t.
We generally want to use uint64_t instead of uintX_t if the 64-bit
type works for both 32-bit and 64-bit because it is simpler than
the variable-size type.

llvm-svn: 300293
2017-04-14 01:34:45 +00:00
Rui Ueyama 1c2b3c43fe Remove useless namespaces.
llvm-svn: 300284
2017-04-13 23:49:54 +00:00
Rui Ueyama 8acbf1cca9 Rename readOutputSectionFiller parseFill.
"read" is used as a prefix for functions that read tokens from input
streams. This function doesn't really read anything, but just parses
a given string as an integer, so rename.

llvm-svn: 300281
2017-04-13 23:40:19 +00:00
Rui Ueyama 15732b718b Fix FILL linker script command.
FILL command doesn't need a semicolon.
Fixes https://bugs.llvm.org/show_bug.cgi?id=32657

llvm-svn: 300280
2017-04-13 23:40:00 +00:00
Rui Ueyama 3e1fc3f6fe Add "1" suffix if there's varaible ends with "2".
If we knew that we'd add End2, Edata2 and Etext2, we'd name their
original symbols with "1". This patch does it.

llvm-svn: 300263
2017-04-13 21:37:56 +00:00
Rui Ueyama 1505ba826c Replace a clever lambda helper with a simpler one.
llvm-svn: 300259
2017-04-13 21:23:03 +00:00
Peter Smith 4dc4bc4e3c [ELF] Tidy up handleARMTlsRelocation [NFC]
Replace addModuleReloc with AddTlsReloc so that we can use it for both the
module relocation and the offset relocation.

Differential Revision: https://reviews.llvm.org/D31751

llvm-svn: 300192
2017-04-13 10:56:40 +00:00
Peter Smith cec1e260c3 [ELF] Mark ARM Exceptions that refer to folded code as not live
ARM Exception Index Table sections .ARM.exidx have an implicit dependency
on code sections via SHF_LINK_ORDER. When code sections are folded by ICF
we must mark the unique .ARM.exidx table that describes it as not live
to prevent an illegal entry in the exception table.
    
Note that we do not try and follow the relocations from the .ARM.exidx
section to the .ARM.extab sections to mark these as not live. Leaving
these sections is not a correctness problem. In theory these could be
removed via an application of garbage collection.
    
Fixes https://bugs.llvm.org/show_bug.cgi?id=32614

Differential Revision: https://reviews.llvm.org/D31932

llvm-svn: 300182
2017-04-13 08:52:58 +00:00
Rui Ueyama 9d773f3cb2 Add comments for the RELRO segment.
RELRO is a feature to make segments read-only after dynamic relocations
are applied. It is different from read-only segments because RELRO is
initially writable. And of course RELRO is different from writable
segments.

RELRO is not a very well known feature. We have a series of checks to
make a decision whether a section should be in a RELRO segment or not,
but we didn't describe why. This patch adds comments to explain how
that decision is made.

llvm-svn: 300176
2017-04-13 05:40:07 +00:00
Rui Ueyama 3233d3eb46 Do not initialize this->SoName with this->DefaultSoName.
This patch uses DefaultSoName in getSoName instead of in parseSoName.
I think this is more readable. This patch also add comments.

llvm-svn: 300147
2017-04-13 00:23:32 +00:00
Rui Ueyama 040af7deab Allow expressions in MEMORY command.
Previously, we allowed only integers in this context. Now you can
write expressions there. LLD is now able to handle the following
linker, for example.

  MEMORY { rom (rx) : ORIGIN = (1024 * 1024) }

llvm-svn: 300131
2017-04-12 23:16:52 +00:00
Evgeniy Stepanov a76349bffe [lld] Keep full library path in DT_NEEDED.
Fixes PR32572.

When
    (a) a library has no soname
and (b) library is given on the command line with path (and not through -L/-l flags)
DT_NEEDED entry for such library keeps the path as given.

This behavior is consistent with gold and bfd, and is used in compiler-rt test suite.

This is a second attempt after r300007 got reverted. This time relro-omagic test is
changed in a way to avoid hardcoding the path to the test directory in the objdump'd
binary.

llvm-svn: 300011
2017-04-12 00:13:48 +00:00
Evgeniy Stepanov d512afe3da Revert "[lld] Keep full library path in DT_NEEDED."
This reverts commit r300007. Reason: breaks all the bots.

llvm-svn: 300008
2017-04-12 00:01:21 +00:00
Evgeniy Stepanov 2c2dcae13c [lld] Keep full library path in DT_NEEDED.
Fixes PR32572.

When
    (a) a library has no soname
and (b) library is given on the command line with path (and not through -L/-l flags)
DT_NEEDED entry for such library keeps the path as given.

This behavior is consistent with gold and bfd, and is used in compiler-rt test suite.

llvm-svn: 300007
2017-04-11 23:46:58 +00:00
Rui Ueyama b58079d4e2 Remove big-endianness from =<fillexp> code.
llvm-svn: 300005
2017-04-11 22:45:57 +00:00
Rui Ueyama 8f8c2f9599 Call getFiller only when filler is not zero.
llvm-svn: 300004
2017-04-11 22:45:38 +00:00
Evgeniy Stepanov 6c973d647f [lld] --export-dynamic overrides --dynamic-list.
Fixes PR32573.

--export-dynamic exports everything, even in the presence of a --dynamic-list,
or --export-dynamic-symbol.

llvm-svn: 300002
2017-04-11 22:37:54 +00:00
George Rimar e7bf968803 [ELF] - Stop producing broken output for R_386_GOT32[X] relocations.
Previously we silently produced broken output for R_386_GOT32X/R_386_GOT32 
relocations if they were used to compute the address of the symbol’s global
offset table entry without base register when position-independent code is disabled.

Situation happened because of recent ABI changes. Released ABI mentions that
R_386_GOT32X can be calculated in a two different ways (so we did not follow ABI here 
before this patch), but draft ABI also mentions R_386_GOT32 relocation here. 
We should use the same calculations for both relocations.

Problem is that we always calculated them as G + A - GOT (offset from end of GOT),
but for case when PIC is disabled, according to i386 ABI calculation should be G + A,
what should produce just an address in GOT finally.

ABI: https://github.com/hjl-tools/x86-psABI/wiki/intel386-psABI-draft.pdf (p36, p60).
llvm-svn: 299812
2017-04-08 06:14:14 +00:00
Rafael Espindola e4c8b9b78c Simplify this further.
Thanks to Rui for noticing it.

llvm-svn: 299777
2017-04-07 16:10:46 +00:00
Simon Atanasyan 60d0e982f0 [ELF] Do not pass GOT section as an argument to handleARMTlsRelocation and handleMipsTlsRelocation functions. NFC
Both functions always use the same GOT sections In<ELFT>::Got and
In<ELFT>::MipsGot respectively, so we do not need to pass them as an
argument.

llvm-svn: 299773
2017-04-07 15:05:44 +00:00
James Henderson 9d9a663731 [ELF] Recommit r299635 to pad x86 executable sections with 0xcc
This follows r299748 which fixed a latent bug the original commit exposed.

llvm-svn: 299755
2017-04-07 10:36:42 +00:00
Peter Smith 99a992343c [ELF] Fix ARM TLS global dynamic TlsOffsetRel for non-preemtible symbols
When the target of the TlsOffsetRel is non-preemptible we can write the
offset directly into the GOT without needing a dynamic relocation. This
is optional for dynamically linked executables but is required for static
linking.
    
This change adds the relocation to the GOT entry and a test case for
non-0 offsets so that if we miss out the offset the test won't spuriously
pass by virtue of the default value being 0.

Differential Revision: https://reviews.llvm.org/D31749

llvm-svn: 299751
2017-04-07 09:37:30 +00:00
Peter Smith a630d0f01b [ELF] Split handleNoRelaxTlsRelocation into ARM and Mips specific impls
The handleNoRelaxTlsRelocation handled both ARM and Mips as at a
high-level the actions of what to do when encountering a local dynamic or
global dynamic TLS relocation are the same. However due to Mips using a
custom GOT the differences of the implementation are enough that the
function became difficult to understand.
    
This change replaces handleNotRelaxTlsRelocation into
handleARMTlsRelocation() and handleMipsTlsRelocation() so that the ARM and
Mips specific code is isolated.

Differential Revision: https://reviews.llvm.org/D31748

llvm-svn: 299750
2017-04-07 09:09:48 +00:00
Rafael Espindola dc8eb810db Move a cast out of a function. NFC.
The argument was always casted, so cast it in the caller.

llvm-svn: 299742
2017-04-07 01:40:21 +00:00
Rafael Espindola 7f91d44fba Remove unnecessary cast.
llvm-svn: 299740
2017-04-07 01:25:01 +00:00
Rui Ueyama 5eb8ea8872 Rename refersToGotEntry needsGot and add comments.
This patch addresses a post-commit review comment for r299615.

Differential Revision: https://reviews.llvm.org/D31792

llvm-svn: 299722
2017-04-06 22:39:11 +00:00
Rafael Espindola d1960dc097 Call updateAlignment before assignAddresses.
The alignment expression cannot depend on '.', so we can compute it
early.

llvm-svn: 299717
2017-04-06 21:40:22 +00:00
Rafael Espindola feed750676 Move call to findMemoryRegion before assignAddresses.
This removes a bit more work from assignAddresses.

llvm-svn: 299716
2017-04-06 21:31:24 +00:00
Rafael Espindola 1902b337e9 Remove redundant argument. NFC.
llvm-svn: 299713
2017-04-06 21:26:03 +00:00
Rafael Espindola 9b9800951d Cache the result of findSection.
This avoids calling it multiple times. In particular, we don't have to
call in in assignAddresses any more.

llvm-svn: 299709
2017-04-06 21:05:39 +00:00
James Henderson d983180778 Revert r299635 because it exposed a latent bug.
llvm-svn: 299655
2017-04-06 15:22:58 +00:00
James Henderson 7ee227561e [ELF] Remove unnecessary cast and fix comments. NFC.
llvm-svn: 299636
2017-04-06 09:40:03 +00:00
James Henderson 8dd4c06a77 [ELF] Pad x86 executable sections with 0xcc int3 instructions
Executable sections should not be padded with zero by default. On some
architectures, 0x00 is the start of a valid instruction sequence, so can confuse
disassembly between InputSections (and indeed the start of the next InputSection
in some situations). Further, in the case of misjumps into padding, padding may
start to be executed silently.

On x86, the "0xcc" byte represents the int3 trap instruction. It is a single
byte long so can serve well as padding. This change switches x86 (and x86_64) to
use this value for padding in executable sections, if no linker script directive
overrides it. It also puts the behaviour into place making it easy to change the
behaviour of other targets when desired. I do not know the relevant instruction
sequences for trap instructions on other targets however, so somebody should add
this separately.

Because the old behaviour simply wrote padding in the whole section before
overwriting most of it, this change also modifies the padding algorithm to write
padding only where needed. This in turn has caused a small behaviour change with
regards to what values are written via Fill commands in linker scripts, bringing
it into line with ld.bfd. The fill value is now written starting from the end of
the previous block, which means that it always starts from the first byte of the
fill, whereas the old behaviour meant that the padding sometimes started mid-way
through the fill value. See the test changes for more details.

Reviewed by: ruiu

Differential Revision: https://reviews.llvm.org/D30886

Bugzilla: http://bugs.llvm.org/show_bug.cgi?id=32227
llvm-svn: 299635
2017-04-06 09:29:08 +00:00
Rui Ueyama 5036cc6768 Create GOT and PLT entries early in scanRelocs().
scanRelocs() does a lot of things. It fills InputSection's Relocations vector,
making a decision whether a TLS relocation should be relaxed or not,
and making a decision whether a GOT/PLT slot needs to be created or not.

They don't actually have to be done in a single loop. I want to separate
them so that some of them can be run concurently. As a first step, this
patch moves PLT/GOT slot assignment to beginning of the loop, so that
they just fall through to the next statements. This should make it clear
that that code doesn't affect other parts of the loop.

llvm-svn: 299615
2017-04-06 03:30:51 +00:00
Rui Ueyama c2a49bf95c Remove Target::isTlsGlobalDynamicRel()
Relocations are abstracted as platform-independent R_TLS_* relocations,
so we don't need to check platform-specific ones to see if a relocation
is TLS GD.

llvm-svn: 299614
2017-04-06 03:30:32 +00:00
Rui Ueyama 5c65088fd4 Return Optional<uint64_t> from readInteger instead of returning just success/failure.
llvm-svn: 299600
2017-04-05 23:22:11 +00:00
Rui Ueyama 0ce388bebb Remove unused typedefs.
llvm-svn: 299594
2017-04-05 21:46:06 +00:00
Rui Ueyama 9f125857ae Inline a small function. NFC.
llvm-svn: 299593
2017-04-05 21:45:47 +00:00
Rui Ueyama 6bd3822007 Use uint64_t to keep file size even on 32-bit machines.
If an output file is too large for 32-bit, we should report an error.

llvm-svn: 299592
2017-04-05 21:37:09 +00:00
Rui Ueyama f2dc4362c0 Inline a small function. NFC.
llvm-svn: 299590
2017-04-05 21:08:47 +00:00
Rui Ueyama 63fda39e2f Remove unnecessary virtual dtor.
This class doesn't have virtual member functions, and no instances
of this class is deleted through base pointers.

llvm-svn: 299581
2017-04-05 19:21:35 +00:00
Rui Ueyama b2fb84a1fa Inline small functions that are used only once.
llvm-svn: 299580
2017-04-05 19:21:15 +00:00
Rui Ueyama 03fc8d1e0d Fix comments.
llvm-svn: 299579
2017-04-05 19:20:54 +00:00
Rui Ueyama 4eb2eccb24 Rename ScriptConfig::UndefinedSymbols ReferencedSymbols.
Symbols referenced by linker scripts are not necessarily be undefined,
so the previous name didn't convey the meaining of the variable.

llvm-svn: 299573
2017-04-05 18:02:30 +00:00
Rui Ueyama 42e0bb5e4f Do not use relocateOne() to just write 32-bit words.
llvm-svn: 299559
2017-04-05 16:33:44 +00:00
Rui Ueyama 69bfab0b38 Rename GotEntryAddr -> GotPltEntryAddr.
Because they are addresses in .got.plt and not in .got.

llvm-svn: 299556
2017-04-05 16:15:59 +00:00
Rui Ueyama 92a5ba6da5 Remove unnecessary local variable.
This patch does what r299506 was trying to do in a different way.

llvm-svn: 299554
2017-04-05 16:07:44 +00:00
Rui Ueyama 9c766d7a39 Fix PLT and GOTPLT entries for 32-bit x86 PIC.
Previously, the code we set to our .plt entries expected that .got
and .got.plt are consecutive in the virtual address space.
Since %ebx points to the last entry of .got for position-independent
code, it assumed that .got is accessible with small negative
displacements and .got.plt are accessible with small positive
displacements.

That assumption was simply wrong. We don't impose any restrictions on
relative layout of .got and .got.plt. As a result, the control is
transferred to a bogus address from .plt at runtime, which resulted in
segfaults.

This patch removes that wrong assumption. We still assume that .got.plt
has a fixed relative address to .got, but we no longer assume that they
are consecutive in memory.

With this change, a "hello world" program compiled with -fPIC works.

Fixes https://bugs.llvm.org/show_bug.cgi?id=31332.

Differential Revision: https://reviews.llvm.org/D31682

llvm-svn: 299553
2017-04-05 16:01:33 +00:00
Peter Smith 56abf209c2 [ELF] Make createThunks a class [NFC]
For range extension thunks we will need to repeatedly call createThunks()
until no more thunks are created. We will need to retain the state of
Thunks that we have created so far to avoid recreating them on later
passes. This change does not change the functionality of createThunks().

Differential Revision: https://reviews.llvm.org/D31654

llvm-svn: 299530
2017-04-05 10:30:09 +00:00
George Rimar e6c5d3862d [ELF] - Define __bss_start symbol.
GNU linkers define __bss_start symbol.
Patch teaches LLD to do that. This is PR32051.

Below is part of standart ld.bfd script:

.data1          : { *(.data1) }
  _edata = .; PROVIDE (edata = .);
  . = .;
  __bss_start = .;
  .bss            :
  {
Currently LLD can emit up to 3 .bss* sections as one of testcase shows.
Implementation inserts this symbol before first .bss* output section.

Differential revision: https://reviews.llvm.org/D30419

llvm-svn: 299528
2017-04-05 10:03:25 +00:00
George Rimar 07d7c42c5d Revert r299506 "Simplify. NFC."
It was not NFC unfortunaly,
one of changes decrements begin() iterator and
that is not allowed by MSVS.

llvm-svn: 299525
2017-04-05 09:19:29 +00:00
Rui Ueyama 23af89cc9a Make readAssert() to return an AssertCommand object.
llvm-svn: 299521
2017-04-05 05:50:28 +00:00
Rui Ueyama 05f6b8527a Add a file comment.
llvm-svn: 299520
2017-04-05 05:50:08 +00:00
Rui Ueyama b579c439c1 Simplify. NFC.
Looks like we can use consume() in many more places.

llvm-svn: 299519
2017-04-05 05:40:21 +00:00
Rui Ueyama 7e9155115e Inline leftShift and rightShift. NFC.
llvm-svn: 299518
2017-04-05 05:40:01 +00:00
Rui Ueyama 96b3fe025a Do not make ScriptParser class public.
This class is used only within this file, so it can be file-local.

llvm-svn: 299516
2017-04-05 05:08:01 +00:00
Rui Ueyama 2ec34544aa Move the parser for the linker script to a separate file.
LinkerScript.cpp contains both the linker script processor and the
linker script parser. I put both into a single file, but the file grown
too large, so it's time to put them into two different files.

llvm-svn: 299515
2017-04-05 05:07:39 +00:00
Rui Ueyama fd9dafdc65 Remove unused typedef.
llvm-svn: 299514
2017-04-05 05:07:18 +00:00
Rui Ueyama 583264e477 Do not use public inheritance where it is not needed.
ScriptParser is not a ScriptLexer, so this should be a private inheritance.

llvm-svn: 299513
2017-04-05 05:06:58 +00:00
Rui Ueyama f62d260744 Simplify. NFC.
llvm-svn: 299512
2017-04-05 05:06:37 +00:00
Rui Ueyama e31d98869d Simplify. NFC.
A for-loop is more boring than a find_if, but I think this is easier to read.

llvm-svn: 299511
2017-04-05 05:06:17 +00:00
Rui Ueyama 01aacc94b9 Fix memory leak found by asan.
llvm-svn: 299509
2017-04-05 03:52:47 +00:00
Rui Ueyama 4e1e88e300 Simplify and update comment.
llvm-svn: 299508
2017-04-05 03:52:28 +00:00
Rui Ueyama c8124ee9a3 Simplify. NFC.
llvm-svn: 299506
2017-04-05 03:21:01 +00:00
Rui Ueyama 8f99f73c8f Use make to create linker script command objects.
It simplifies variable types.

llvm-svn: 299505
2017-04-05 03:20:42 +00:00
Rui Ueyama d379f7357d Remove default arguments because they don't improve readability.
llvm-svn: 299504
2017-04-05 03:20:22 +00:00
Rui Ueyama cba41013ef Add parentheses around `&`.
llvm-svn: 299503
2017-04-05 03:20:03 +00:00
Rui Ueyama d7c5400f9e Update comment.
llvm-svn: 299502
2017-04-05 03:19:43 +00:00
Rui Ueyama cc400cc8ac Use empty() instead of size().
`!V.size()` where V is a vector is equivalent to `V.empty()`.

llvm-svn: 299501
2017-04-05 03:19:24 +00:00
Rui Ueyama 0b2381e71f Simplify. NFC.
llvm-svn: 299500
2017-04-05 03:19:06 +00:00
Rui Ueyama 2e081a4ff0 Make variable names consistent. NFC.
llvm-svn: 299499
2017-04-05 03:18:46 +00:00
Rui Ueyama 72e107f302 Return a result from computeInputSections instead of mutating its argument.
This should improve readability.

llvm-svn: 299498
2017-04-05 02:05:48 +00:00
Rui Ueyama 2c7171bf3c Remove `=` from a lambda that doesn't capture any variable.
llvm-svn: 299495
2017-04-05 00:43:45 +00:00
Rui Ueyama ea93fe00b9 Inline small functions that are used only once as lambdas.
llvm-svn: 299494
2017-04-05 00:43:25 +00:00
Rui Ueyama 5f20b6304b Add newlines.
llvm-svn: 299493
2017-04-05 00:43:05 +00:00
Rui Ueyama a08fa2eca3 Make dummy variable's scope smaller.
llvm-svn: 299492
2017-04-05 00:42:45 +00:00
Rafael Espindola 8465d08392 Don't resolve hidden undef to a DSO.
The ELF spec says:

all of the non-default visibility attributes, when applied to a symbol
reference, imply that a definition to satisfy that reference must be
provided within the current executable or shared object.

But we were trying to resolve those undef references to shared
symbols. That causes odd results like creating a got entry with
a relocation pointing to 0.

llvm-svn: 299464
2017-04-04 20:03:34 +00:00
James Henderson b7a90ef48e [ELF] Fail the link early if the map file path is invalid
As with the changes made in r297645, we do not want a potentially long link to
be run, if it will ultimately fail because the map file is not writable. This
change reuses the same functionality as the output file path check. See
https://reviews.llvm.org/D30449 for further justification and explanations.

Reviewers: ruiu

Differential Revision: https://reviews.llvm.org/D31603

llvm-svn: 299420
2017-04-04 09:42:24 +00:00
Peter Smith 6308ac2254 [ELF] Rename ARM Thunks in anticipation of Range Thunks
The existing names for the ARM and Thumb Thunks highlight their current
use as interworking Thunks. These Thunks can also be used for range
extension Thunks where there is no state change. This change makes the name
more generic so it is suitable for range extension.

Differential Revision: https://reviews.llvm.org/D31605

llvm-svn: 299418
2017-04-04 09:29:36 +00:00
Rui Ueyama 6ea72527e0 Change the error message format for an incompatible relocation.
Previous error message style:

  error: /home/alice/src/bar.c:12: relocation R_X86_64_PLT32 cannot refer to absolute symbol 'answer' defined in /home/alice/src/foo.o

New error message style:

  error: relocation R_X86_64_PLT32 cannot refer to absolute symbol: foo
  >>> defined in /home/alice/src/foo.o
  >>> referenced by bar.c:12 (/home/alice/src/bar.c:12)
  >>>               /home/alice/src/bar.o:(.text+0x1)

llvm-svn: 299390
2017-04-03 21:36:31 +00:00
Rui Ueyama c49bb0f418 Make a helper function file-local.
llvm-svn: 299377
2017-04-03 19:14:35 +00:00
Rui Ueyama 4e4e8662bc Remove InputFiles::LogName.
LogName member was added to construct input file names for logging
only once. This patch does this in a different way. Now toString
caches its results.

Differential Revision: https://reviews.llvm.org/D31546

llvm-svn: 299375
2017-04-03 19:11:23 +00:00
Rui Ueyama 3a965f7e68 Change the error format to report corrupted .eh_frame.
llvm-svn: 299289
2017-04-01 01:42:20 +00:00
Rui Ueyama 810ce10b8c Change the error message format for duplicate symbols.
This patch is intended to improve readability of "duplicate symbol"
error messages.

Without this patch:

  /ssd/clang/bin/ld.lld: error: /ssd/llvm-project/lld/ELF/Relocations.cpp:1054: duplicate symbol 'lld:🧝:demangle(llvm::StringRef)'
  /ssd/clang/bin/ld.lld: error: /ssd/llvm-project/lld/ELF/Strings.cpp:93: previous definition was here

With this patch:

  /ssd/clang/bin/ld.lld: error: duplicate symbol: lld:🧝:demangle(llvm::StringRef)
  >>> defined at Strings.cpp:93 (/ssd/llvm-project/lld/ELF/Strings.cpp:93)
  >>>            Strings.cpp.o:(lld:🧝:demangle(llvm::StringRef)) in archive lib/liblldELF.a
  >>> defined at Relocations.cpp:1054 (/ssd/llvm-project/lld/ELF/Relocations.cpp:1054)
  >>>            Relocations.cpp.o:(.text+0x4C30) in archive lib/liblldELF.a

Discussion thread:
http://lists.llvm.org/pipermail/llvm-dev/2017-March/111459.html

Differential Revision: https://reviews.llvm.org/D31507

llvm-svn: 299280
2017-03-31 23:40:21 +00:00
James Henderson 50c374f37a Remove unnecessary cast and branch. NFC.
llvm-svn: 299208
2017-03-31 12:31:23 +00:00
Peter Collingbourne 7b30f16c9f Re-apply r299168 and r299169 now that the libdeps are fixed.
llvm-svn: 299184
2017-03-31 04:47:07 +00:00
Peter Collingbourne f10698b940 Revert r299168 and r299169 due to library dependency issues.
http://bb.pgr.jp/builders/i686-mingw32-RA-on-linux/builds/25073/steps/build_llvmclang/logs/stdio

llvm-svn: 299171
2017-03-31 02:44:50 +00:00
Peter Collingbourne d9717aa0e4 LTO: Reduce memory consumption by creating an in-memory symbol table for InputFiles. NFCI.
Introduce symbol table data structures that can be potentially written to
disk, have the LTO library build those data structures using temporarily
constructed modules and redirect the LTO library implementation to go through
those data structures. This allows us to remove the LLVMContext and Modules
owned by InputFile.

With this change I measured a peak memory consumption decrease from 5.4GB to
2.8GB in a no-op incremental ThinLTO link of Chromium on Linux. The impact on
memory consumption is larger in COFF linkers where we are currently forced
to materialize all metadata in order to read linker options. Peak memory
consumption linking a large piece of Chromium for Windows with full LTO and
debug info decreases from >64GB (OOM) to 15GB.

Part of PR27551.

Differential Revision: https://reviews.llvm.org/D31364

llvm-svn: 299168
2017-03-31 02:28:30 +00:00
Rui Ueyama 6117a624db Update comments.
llvm-svn: 299128
2017-03-30 22:57:49 +00:00
Rui Ueyama 37e60a52f3 Include filenames in error messages to report broken files.
llvm-svn: 299115
2017-03-30 21:13:00 +00:00
Rui Ueyama 66611d94ad Do not enclose an entire file with namespaces.
This change is to improve consistency with other files.

llvm-svn: 299110
2017-03-30 20:31:19 +00:00
Rui Ueyama b87602032a Change the error message format for undefined symbols.
Previously, undefined symbol errors are one line like this
and wasn't easy to read.

  /ssd/clang/bin/ld.lld: error: /ssd/llvm-project/lld/ELF/Writer.cpp:207: undefined symbol 'lld:🧝:EhFrameSection<llvm::object::ELFType<(llvm::support::endianness)0, true> >::addSection(lld:🧝:InputSectionBase*)'

This patch make it more structured like this.

  bin/ld.lld: error: undefined symbol: lld:🧝:EhFrameSection<llvm::object::ELFType<(llvm::support::endianness)0, true>
  >>> Referenced by Writer.cpp:207 (/ssd/llvm-project/lld/ELF/Writer.cpp:207)
  >>>               Writer.cpp.o in archive lib/liblldELF.a

Discussion thread:
http://lists.llvm.org/pipermail/llvm-dev/2017-March/111459.html

Differential Revision: https://reviews.llvm.org/D31481

llvm-svn: 299097
2017-03-30 19:13:47 +00:00
Rui Ueyama 8d753caa78 Remove parameter names from template instantiations to make them compact. NFC.
llvm-svn: 299025
2017-03-29 20:15:29 +00:00
Rui Ueyama aa693468c5 Revert r298815: Do not use assert to report broken input files.
This reverts commit because this really shouldn't happen unless
there's a bug in LLD.

llvm-svn: 299021
2017-03-29 19:35:44 +00:00
George Rimar 5f73bc9517 [ELF] - Prepare GnuHashTableSection<ELFT> for detemplation.
This patch changes GnuHashTableSection implementation
to avoid depend on uintX_t and other ELFT stuff, reducing amount of 
changes for following patch(es).

Differential revision: https://reviews.llvm.org/D31184

llvm-svn: 298998
2017-03-29 15:23:28 +00:00
Rui Ueyama fb0f093e88 Attempt to fix buildbot.
llvm-svn: 298971
2017-03-29 01:36:37 +00:00
Rui Ueyama 6022b2be55 Use uint64_t instead of uintX_t and size_t.
uint64_t is simpler and less error-prone than target or host-dependent types.

llvm-svn: 298969
2017-03-29 00:49:50 +00:00
Rui Ueyama c95671bd78 Change the order of parameters. NFC.
If a function takes a size and an alignment, we usually pass them
in that order instead of the reverse order.

llvm-svn: 298968
2017-03-29 00:49:29 +00:00
Rui Ueyama 00805d8b09 Remove a comment that is taken from gdb man page.
This is not an original comment but taken from gdb man page, so
a pointer to the original document should suffice.

llvm-svn: 298964
2017-03-29 00:09:40 +00:00
Peter Collingbourne 0d56b959ad LTO: Replace InputFile::Symbol::getFlags() with predicate accessors. NFC.
This makes the predicates independent of the flag representation
and makes the code a little easier to read.

llvm-svn: 298951
2017-03-28 22:31:35 +00:00
Rui Ueyama 486369fc1a Do not set entsize for .gnu.hash.
.gnu.hash happen to contain only 32-bit integers for 32-bit arch,
but the section contents are not uniform array members, so setting
entsize doesn't make much sense. This behavior seems to have been
blindly copied from GNU linkers.

llvm-svn: 298934
2017-03-28 18:11:52 +00:00
Rui Ueyama 70c8efd03c Sort.
llvm-svn: 298829
2017-03-27 03:42:55 +00:00
Rui Ueyama ceb5bd59cc Simplify. NFC.
This patch calls getAddend on a relocation only when the relocation is RELA.
That doesn't really improve runtime performance but should improve
readability as the code now matches the function description.

llvm-svn: 298828
2017-03-27 03:41:00 +00:00
Rui Ueyama 4c6dfbdc20 Factor out code to add a GOT entry.
llvm-svn: 298821
2017-03-26 21:00:09 +00:00
Rui Ueyama 37c3c2d0ca Factor out common code.
llvm-svn: 298818
2017-03-26 20:51:14 +00:00
Rui Ueyama a2f63f1471 Remove MIPS-specific code from computeAddend.
Previously, computeAddend had many parameters but most of them were
used only for MIPS. The MIPS ABI is too odd that I don't want to mix
it into the regular code path. Splitting the function into non-MIPS
and MIPS parts makes the regular code path easy to follow.

llvm-svn: 298817
2017-03-26 19:35:24 +00:00
Rui Ueyama 09fd21f45c Do not use assert to report broken input files.
llvm-svn: 298815
2017-03-26 18:23:22 +00:00
Rui Ueyama 8d462b2b5f Update comments.
llvm-svn: 298814
2017-03-26 18:23:00 +00:00
Rui Ueyama ff524bf739 Sort. NFC.
llvm-svn: 298797
2017-03-26 04:10:43 +00:00
Rui Ueyama f7c2b0cb49 Remove a redundant local variable.
llvm-svn: 298796
2017-03-26 03:42:00 +00:00
Rui Ueyama a588b5fcdc Add a comment.
llvm-svn: 298795
2017-03-26 03:41:41 +00:00
Rui Ueyama 2bb35f6844 Inline a function that is used only once.
llvm-svn: 298794
2017-03-26 03:21:08 +00:00
Rui Ueyama 94e36c894e De-template a few functions in which ELFT is not needed.
llvm-svn: 298793
2017-03-26 03:20:49 +00:00
Rui Ueyama 760197cef1 Add comments and return early.
llvm-svn: 298792
2017-03-26 03:20:30 +00:00
Rui Ueyama beeab45770 Remove unused parameter.
llvm-svn: 298790
2017-03-26 02:28:09 +00:00
Rui Ueyama cb815ac549 Remove redundant local variables.
llvm-svn: 298789
2017-03-26 02:27:50 +00:00
Rui Ueyama b5cb328383 Remove a parameter from adjustExpr. NFC.
llvm-svn: 298788
2017-03-26 02:27:30 +00:00
Rui Ueyama dfd204fa1d Inline a small lambda.
llvm-svn: 298787
2017-03-26 02:27:11 +00:00
Rui Ueyama 2f274230f1 Rename C -> Sec and RI -> Rel.
C is short for Chunk, but we are no longer using that term.
RI is probably short for relocation iterator, but this is not an interator.

llvm-svn: 298786
2017-03-26 02:26:52 +00:00
Rui Ueyama 08aede362b Simplify relocation offset adjustment.
Previously, relocation offsets are recalculated for .eh_frame sections
inside the main loop, and that messed up the main loop. This patch
separates that logic into a dedicated class.

llvm-svn: 298785
2017-03-26 02:26:33 +00:00
Rui Ueyama 22f0d804f5 Use raw_fd_ostream::has_colors instead of StandardErrHasColors().
I just didn't know that raw_fd_ostream has has_colors() function.

llvm-svn: 298749
2017-03-24 23:21:34 +00:00
Rui Ueyama 561d72c328 Update comment.
llvm-svn: 298748
2017-03-24 23:21:14 +00:00
Rui Ueyama c3ddb655cc Return early.
llvm-svn: 298675
2017-03-24 01:13:30 +00:00
Rui Ueyama 2c88cee15c Early continue. NFC.
The original code is a big `if` and `else` which ends with `continue`
like this:

  if (cond) {
    ...
    // fall through
  } else {
    ...
    continue;
  }

This patch rewrites it with the following.

  if (!cond) {
    ...
    continue;
  }
  ...

llvm-svn: 298672
2017-03-24 00:50:37 +00:00
Rui Ueyama 81cb710784 Update comments.
llvm-svn: 298669
2017-03-24 00:15:57 +00:00
Rui Ueyama be68fe18cc Use `using namespace lld` for consistency with other files.
llvm-svn: 298668
2017-03-24 00:15:37 +00:00
Rui Ueyama 9b55e92a7f Move a few functions to a new file Filesystem.{cpp,h}.
llvm-svn: 298667
2017-03-24 00:15:16 +00:00
Rui Ueyama 0cbf1fd2f6 Fix varaible names that correspond to command line options.
llvm-svn: 298632
2017-03-23 18:16:42 +00:00
Simon Atanasyan 6ab0d5b0d1 [ELF] Print two more MIPS targets "supported" by LLD
These targets are related to MIPS N32 ABI.

llvm-svn: 298591
2017-03-23 12:17:32 +00:00
Petr Hosek 30f16b2339 [ELF] Allow references to reserved symbols in linker scripts
This requires collectign all symbols referenced in the linker script
and adding them to symbol table as undefined symbol.

Differential Revision: https://reviews.llvm.org/D31147

llvm-svn: 298577
2017-03-23 03:52:34 +00:00
Rui Ueyama 968381ef22 Simplify. No functionality change intended.
I honestly do not understand this part of code as it is too tangled.
What I'm trying now is to carefully disentangle it by transforming
code without changing meaining to see if I can improve overall
readability.

llvm-svn: 298576
2017-03-23 03:44:08 +00:00
Rui Ueyama ccf71c6ab3 Remove unnecessary local variable.
llvm-svn: 298575
2017-03-23 03:11:03 +00:00
Rui Ueyama 688299bd39 Refine comment.
llvm-svn: 298571
2017-03-23 01:19:10 +00:00
Rui Ueyama 34e3d50d18 Force @{init,fini}_array if section name starts with ".{init,fini}_array.".
Fixes https://bugs.llvm.org/show_bug.cgi?id=32307.

Differential Revision: https://reviews.llvm.org/D31255

llvm-svn: 298569
2017-03-23 01:00:41 +00:00
Rui Ueyama b57412e95d Print out "suppoted targets".
This is to improve compatibility with GNU Libtool that expect
/supported targets:.* elf/ in a message for the -help option.

Differential Revision: https://reviews.llvm.org/D31208

llvm-svn: 298568
2017-03-23 01:00:22 +00:00
Davide Italiano 7690721153 [ELF] Add -z nodlopen option.
Patch by Mark Kettenis.

llvm-svn: 298567
2017-03-23 00:54:16 +00:00
Rui Ueyama 4995afd943 Rename forEach -> parallelForEach and forLoop -> parallelFor.
"Parallel" is the most important aspect of the functions,
so we shouldn't omit that.

llvm-svn: 298557
2017-03-22 23:03:35 +00:00
Rui Ueyama bdc8bc047d Add "(compatible with GNU linkers)" to the -version output.
Previous output:

  $ ld.lld -version
  LLD 5.0.0

New output:

  $ ld.lld -version
  LLD 5.0.0 (compatible with GNU linkers)

Differential Revision: https://reviews.llvm.org/D31199

llvm-svn: 298532
2017-03-22 18:04:57 +00:00
Rui Ueyama 7ab38c3a12 Define Config::Is64.
This is a shorthand for Config->Wordsize == 8. So this is not strictly
necessary but seems handy. "Is 64 bit?" is easier to read than "Is
wordsize 8 byte?"

llvm-svn: 298463
2017-03-22 00:01:11 +00:00
Rui Ueyama a34da93847 Make elf::ScriptConfig a LinkerScript class member variable.
LinkerScript used to be a template class, so we couldn't instantiate
that class in elf::link. We instantiated ScriptConfig class earlier
instead so that the linker script parser can store configurations to
the object.

Now that LinkerScript is not a template, it doesn't make sense to
separate ScriptConfig from LinkerScript. This patch merges them.

llvm-svn: 298457
2017-03-21 23:03:09 +00:00
Rui Ueyama b8dd23f56e Rename LinkerScriptBase -> LinkerScript.
llvm-svn: 298456
2017-03-21 23:02:51 +00:00
Rui Ueyama fc16173ceb Sort. NFC.
llvm-svn: 298447
2017-03-21 21:49:16 +00:00
Rui Ueyama f93ed4de2e Define Config::Endianness.
This is a shorthand for `Config->IsLE ? support::little : support::big`.

llvm-svn: 298445
2017-03-21 21:40:08 +00:00
Rui Ueyama ca7818ebca Update comment.
llvm-svn: 298403
2017-03-21 17:22:13 +00:00
George Rimar 1ec03e46a7 [ELF] - Detemplate InputSection::getRelocatedSection(). NFC.
llvm-svn: 298353
2017-03-21 09:13:27 +00:00
George Rimar 76e562ab1b [ELF] - Detemplate InputSectionBase::uncompress(). NFC
llvm-svn: 298351
2017-03-21 09:08:58 +00:00
George Rimar 90a528ba7a [ELF] - Detemplate ARMExidxSentinelSection. NFC.
llvm-svn: 298350
2017-03-21 09:01:39 +00:00
George Rimar f56cadd3b3 [ELF] - Fix one more access to Sections member.
That finally should linux BB after r298345.

llvm-svn: 298349
2017-03-21 08:57:13 +00:00
George Rimar 3f7c3df6a4 [ELF] Follow-up to r298345 "[ELF] - Detemplate GdbIndexSection."
Fix for linux build bot:
http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast/builds/8144/steps/build/logs/stdio

llvm-svn: 298348
2017-03-21 08:44:25 +00:00
George Rimar 9353e2dbfb [ELF] - Detemplate InputSectionBase::getLinkOrderDep(). NFC.
llvm-svn: 298346
2017-03-21 08:29:48 +00:00
George Rimar 35e846e14d [ELF] - Detemplate GdbIndexSection.
Patch moves Sections array to
InputFile (root class for input files).

That allows to detemplate GdbIndexSection.

Differential revision: https://reviews.llvm.org/D30976

llvm-svn: 298345
2017-03-21 08:19:34 +00:00
Rafael Espindola b57e496dfa Move OffsetInArchive to BitcodeFile.
It is the only file type that needs it.

llvm-svn: 298323
2017-03-20 23:47:06 +00:00
Simon Atanasyan d34a3631b2 [ELF][MIPS] Calculate relocations agains _gp_disp / __gnu_local_gp using dedicated 'expressions'
The patch introduces two new relocations expressions R_MIPS_GOT_GP and
R_MIPS_GOT_GP_PC. The first one represents a current value of `_gp`
pointer and used to calculate relocations against the `__gnu_local_gp`
symbol. The second one represents the offset between the beginning of
the function and the `_gp` pointer's value.

There are two motivations for introducing new expressions:
- It's better to keep all non-trivial relocation calculations in the
  single place - `getRelocTargetVA` function.
- Relocations against both `_gp_disp` and `__gnu_local_gp` symbols
  depend on the `_gp` value. It's a magical value points to the "middle"
  of GOT. Now all relocations use a common `_gp` value. But in fact,
  under some conditions each input file might require its own `_gp`
  value. I'm going to implement it in the future patches. So it's
  better to make `MipsGotSection` responsible for calculation of
  the `_gp` value.

llvm-svn: 298306
2017-03-20 21:03:43 +00:00
Simon Atanasyan 5378e423e5 [ELF][MIPS] Follow-up to r298272. Fix typo to fix buildbot.
llvm-svn: 298304
2017-03-20 20:49:44 +00:00
George Rimar 14534eb8a2 [ELF] - Detemplate MipsGotSection<ELFT>
This continues detemplation process.

Detemplating MipsGotSection<ELFT> is helpfull because can
help to detemplate getRelocTargetVA. (one more change is required)
It opens road to detemplation of GotSection<ELFT> and probably
something else after that.

Differential revision: https://reviews.llvm.org/D31090

llvm-svn: 298272
2017-03-20 16:44:28 +00:00
George Rimar 6c2949da39 [ELF] - Detemplate BuildIdSection section.
Does not introduce anything new,
just performs detemplate, using methods we
already have.

Differential revision: https://reviews.llvm.org/D30935

llvm-svn: 298269
2017-03-20 16:40:21 +00:00
Rafael Espindola 195f23c53b Inline a few functions.
I don't foresee having to makes these functions any stricter or
fancier, so it probably makes sense to inline them.

llvm-svn: 298252
2017-03-20 14:35:41 +00:00
Rafael Espindola 49592cf679 Initialize dot.
This would fix an initialized error found by msan. The error is not
showing after r298241, but it is not clear why.

llvm-svn: 298251
2017-03-20 14:33:33 +00:00
George Rimar 05423488a1 [ELF] - Simplify redundant templated call. NFC.
llvm-svn: 298244
2017-03-20 10:47:00 +00:00
George Rimar f6abfd7a53 [ELF] - Get rid of uintX_t in GdbIndexSection. NFC.
llvm-svn: 298243
2017-03-20 10:40:40 +00:00
George Rimar b17d16a2a1 [ELF] - Reuse Config->IsLE. NFC.
llvm-svn: 298242
2017-03-20 10:16:57 +00:00
George Rimar a8dba48762 [ELF] - Combine LinkerScriptBase and LinkerScript<ELFT>
Patch removes templated linkerscript class.

Unfortunately that required 2 additional static methods
findSymbol() and addRegularSymbol() because code
depends on Symtab<ELFT>::X

Differential revision: https://reviews.llvm.org/D30982

llvm-svn: 298241
2017-03-20 10:09:58 +00:00
George Rimar 009833d377 [ELF] - Apply clang-format. NFC.
llvm-svn: 298240
2017-03-20 09:51:18 +00:00
Simon Atanasyan 8c75311906 [ELF] clang-format sortMipsSymbols. NFC
llvm-svn: 298230
2017-03-19 19:32:51 +00:00
Rui Ueyama d57e74b7d3 Compute Config member function return values only once.
We had a few Config member functions that returns configuration values.
For example, we had is64() which returns true if the target is 64-bit.
The return values of these functions are constant and never change.

This patch is to compute them only once to make it clear that they'll
never change.

llvm-svn: 298168
2017-03-17 23:29:01 +00:00
Rui Ueyama fd06b73466 Define Config::isLE and Config::wordsize.
isLE() return true if the target is little-endian.
wordsize() returns 8 for 64-bit and 4 for 32-bit.

llvm-svn: 298167
2017-03-17 23:28:41 +00:00
Peter Collingbourne 5758b2e488 ELF: Change check(Expected<T>, const Twine &) to call toString instead of converting to an error code.
llvm-svn: 298155
2017-03-17 22:06:36 +00:00
Evgeniy Stepanov 4b78036ba8 [ELF] Restore GC handling of LINK_ORDER, C-named sections.
__start_xxx symbol keeps section xxx alive only if it is not
SHF_LINK_ORDER. Such sections can be used for user metadata, when
__start_xxx is used to iterate over section contents at runtime, and
the liveness is determined solely by the linked (associated) section.

This was earlier implemented in r294592, and broken in r296723.

Differential Revision: https://reviews.llvm.org/D30964

llvm-svn: 298154
2017-03-17 22:04:52 +00:00
Bob Haarman f790f788b6 recommend using llvm-ar when finding undefined references and empty archives
Summary:
When we perform LTO builds with a version of ar that does not
understand LLVM bitcode objects, we end up with undefined references,
because our archive files do not list the bitcode symbols in their
indices. The error messages do not make it clear what the real problem
is. This change adds a note that points out the likely problem and
solution. It is similar in spirit to r282633, but aims to avoid false
positives by only triggering when we see both undefined references and
archives without symbols in their indices.

Fixes PR32281.

Reviewers: davide, ruiu, tejohnson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D31011

llvm-svn: 298124
2017-03-17 21:32:49 +00:00
George Rimar a918957b05 [ELF] - Move template instantiations to the end of file. NFC.
To be consistent with other code, addresses post 
commit review comments.

llvm-svn: 298102
2017-03-17 16:50:07 +00:00
Rafael Espindola 7ba5f47eb8 Handle & and | of non abs values.
Handling & in particular is probably important because of its use in
aligning addresses.

llvm-svn: 298096
2017-03-17 14:55:36 +00:00
Rafael Espindola 5f08a1dca8 Refuse to add two non absolute symbols.
Since there is no way to produce the correct answer at runtime, it is
probably better to just err.

llvm-svn: 298094
2017-03-17 14:51:07 +00:00
Simon Atanasyan 462f84a736 [ELF][MIPS] Always collect .reginfo, .MIPS.options, and .MIPS.abiflags input sections
Do not take in account the `Live` flag while collecting .reginfo, .MIPS.options,
and .MIPS.abiflags input sections to produce corresponding output sections.
These sections have information purpose and should be always produced per
ABI requirements.

llvm-svn: 298093
2017-03-17 14:27:55 +00:00
George Rimar 4afe42e5c4 [ELF] - Detemplate SymbolBody::getGotOffset(). NFC.
llvm-svn: 298091
2017-03-17 14:12:51 +00:00
Rafael Espindola f2115f04c8 Support non abs values in the rhs of +.
llvm-svn: 298088
2017-03-17 13:45:36 +00:00
George Rimar 8fe7aea527 [ELF] - Detemplate findSection() global static method. NFC.
llvm-svn: 298087
2017-03-17 13:43:24 +00:00
George Rimar 176d606020 [ELF] - Recommit r298078 "[ELF] - Simplify logic of creating "COMMON" section."
With fix of next warning:
Writer.cpp:361:3: warning: suggest parentheses around assignment used as truth value [-Wparentheses]

Original commit message:

Patch reuses BssSection section to simplify creation of 
COMMON section.

Differential revision: https://reviews.llvm.org/D30690

llvm-svn: 298086
2017-03-17 13:31:07 +00:00
George Rimar 4ddd9c9bd6 [ELF] - Revert r298078 and 298082
It segfaults.

llvm-svn: 298084
2017-03-17 13:21:22 +00:00
George Rimar 69739e6d1d [ELF] - Fix warning.
Writer.cpp:361:3: warning: suggest parentheses around assignment used as truth value [-Wparentheses]

llvm-svn: 298082
2017-03-17 13:15:35 +00:00
Rafael Espindola 72dc195d78 Change our linker script expr representation.
This fixes pr32031 by representing the expressions results as a
SectionBase and offset. This allows us to use an input section
directly instead of getting lost trying to compute an offset in an
outputsection when not all the information is available yet.

This also creates a struct to represent the *value* of and expression,
allowing the expression itself to be a simple typedef. I think this is
easier to read and will make it easier to extend the expression
computation to handle more complicated cases.

llvm-svn: 298079
2017-03-17 13:05:04 +00:00
George Rimar f6c300e86d [ELF] - Simplify logic of creating "COMMON" section.
Patch reuses BssSection section to simplify creation of 
COMMON section.

Differential revision: https://reviews.llvm.org/D30690

llvm-svn: 298078
2017-03-17 13:04:06 +00:00
Rafael Espindola 490fccb170 Remove unnecessary (). NFC.
llvm-svn: 298076
2017-03-17 13:00:45 +00:00
George Rimar 97def8c2ff [ELF] - Detemplate DynamicReloc class. NFC.
llvm-svn: 298072
2017-03-17 12:07:44 +00:00
George Rimar f64618a621 [ELF] - Detemplate SymbolBody::getVA and SymbolBody::getPltVA. NFC.
llvm-svn: 298071
2017-03-17 11:56:54 +00:00
George Rimar 5a5c54f78e [ELF] - Fix linux build bot.
Error was:
Relocations.cpp:792:38: error: expected primary-expression before ‘>’ token
         In<ELFT>::Iplt->addEntry<ELFT>(Body);

llvm-svn: 298070
2017-03-17 11:41:56 +00:00
George Rimar dfc020e9f9 [ELF] - Detemplate PltSection. NFC.
Alternative approach can be remove templated method
either, like D31028 do.

llvm-svn: 298065
2017-03-17 11:01:57 +00:00
George Rimar 1ab9cf49d0 [ELF] - Recommit "[ELF] - Make Bss and BssRelRo sections to be synthetic (#3)."
Was fixed, details on review page.

Original commit message:

That removes CopyRelSection class completely, making
Bss/BssRelRo to be just regular synthetics.

This is splitted from D30541 and polished.
Difference from D30541 that all logic of SharedSymbol
converting to DefinedRegular was removed for now and
probably will be posted as separate patch.

Differential revision: https://reviews.llvm.org/D30892

llvm-svn: 298062
2017-03-17 10:14:53 +00:00
Peter Collingbourne ee59e43f92 ELF: Add cache pruning support.
This patch causes us to use pruneCache() to prune the ThinLTO cache after
completing LTO. A new flag --thinlto-cache-policy allows users to configure
the policy.

Differential Revision: https://reviews.llvm.org/D31021

llvm-svn: 298036
2017-03-17 02:24:16 +00:00
Peter Collingbourne 128423f99b LTO: Fix a potential race condition in the caching API.
After the call to sys::fs::exists succeeds, indicating a cache hit, we call
AddFile and the client will open the file using the supplied path. If the
client is using cache pruning, there is a potential race between the pruner
and the client. To avoid this, change the caching API so that it provides
a MemoryBuffer to the client, and have clients use that MemoryBuffer where
possible.

This scheme won't work with the gold plugin because the plugin API expects a
file path. So we have the gold plugin use the buffer identifier as a path and
live with the race for now. (Note that the gold plugin isn't actually affected
by the problem at the moment because it doesn't support cache pruning.)

This effectively reverts r279883 modulo the change to use the existing path
in the gold plugin.

Differential Revision: https://reviews.llvm.org/D31063

llvm-svn: 298020
2017-03-17 00:34:07 +00:00
Rui Ueyama 98e55de699 Revert r297850: [ELF] - Linkerscript: make Dot public and remove getDot(). NFC.
This reverts commit r297850 because this change was made
based on a miscommunication.

llvm-svn: 298001
2017-03-16 21:50:30 +00:00
George Rimar 7385d4358a [ELF] - Rename Config->Is64Bit() to is64(). NFC.
Addresses post commit review comment.

llvm-svn: 297953
2017-03-16 13:41:29 +00:00
George Rimar 4670bb00b5 [ELF] - Detemplate SymbolBody::getGotPltVA and SymbolBody::getGotPltOffset(). NFC.
That opens road to detemplate PltSection<ELFT>,
what allows then to detemplate all methods of SymbolBody.

llvm-svn: 297950
2017-03-16 12:58:11 +00:00
George Rimar f00c183847 [ELF] Fix builbot.
Excessive typename keyword.

llvm-svn: 297949
2017-03-16 12:20:19 +00:00
George Rimar a0b1e2c3d8 [ELF] - Don't use uintX_t in DynamicReloc<ELFT>. NFC.
That allows to detemplate getGotPltOffset/getGotPltVA
methods of SymbolBody and also will help to detemplate
DynamicReloc itself later.

llvm-svn: 297946
2017-03-16 11:42:16 +00:00
George Rimar 7702bc237e [ELF] - Removed unused templates #4. NFC.
llvm-svn: 297944
2017-03-16 11:20:02 +00:00
George Rimar 69268a8ab3 [ELF] - Detemplate SymbolBody::getOutputSection(). NFC.
llvm-svn: 297943
2017-03-16 11:06:13 +00:00
George Rimar a92dc2bbd3 [ELF] - Removed unused template #3. NFC.
llvm-svn: 297942
2017-03-16 10:55:45 +00:00
George Rimar d3ea775894 [ELF] - Removed unused template #2. NFC.
llvm-svn: 297941
2017-03-16 10:48:40 +00:00
George Rimar 7b8270424e [ELF] Detemplate ThunkSection and Thunk classes. NFC.
llvm-svn: 297939
2017-03-16 10:40:50 +00:00
George Rimar 49a47f2a6d [ELF] - Removed unused template #1. NFC
llvm-svn: 297938
2017-03-16 10:29:44 +00:00
George Rimar f98c5c126c [ELF] - Detemplate OutputSection::assignOffsets. NFC.
llvm-svn: 297937
2017-03-16 10:24:54 +00:00
George Rimar 47bed8c9f7 Revert r297813 "[ELF] - Make Bss and BssRelRo sections to be synthetic (#3)."
I suppose it is the reason of BB fail:
http://lab.llvm.org:8011/builders/clang-cmake-aarch64-lld/builds/921

https://bugs.llvm.org/show_bug.cgi?id=32167

llvm-svn: 297933
2017-03-16 08:44:53 +00:00
George Rimar 20055d4cd2 [ELF] - Linkerscript: make Dot public and remove getDot(). NFC.
Suggested by Rui Ueyama,
also groups member variables in a single place, while I am here.

llvm-svn: 297850
2017-03-15 16:07:02 +00:00
George Rimar 503206c567 [ELF] - Move LinkerScript::discard to LinkerScriptBase. NFC.
Became possible after r297844

llvm-svn: 297848
2017-03-15 15:42:44 +00:00
George Rimar 9782ca5b68 [ELF] - Split struct In<ELFT> to have templated and non-templated sections areas.
Patch splits In<ELFT> into 2 classes: one for non-templated sections, 
second contains ELFT templated ones.
That allows to code that was detemplated to access non-templated sections freely,
and should open road for futher detemplation proccess.

Differential revision: https://reviews.llvm.org/D30939

llvm-svn: 297844
2017-03-15 15:29:29 +00:00
Rafael Espindola 4820060dc6 Use uint32_t for alignment.
llvm-svn: 297831
2017-03-15 12:43:54 +00:00
Rafael Espindola a156555b5e simplify. NFC
llvm-svn: 297829
2017-03-15 12:31:54 +00:00
George Rimar 42886c4b47 [ELF] - Detemplate MipsRldMapSection. NFC.
After introducing Config->is64Bit() and 
recent changes in LinkerScriptBase, some
sections can be detemplated trivially. This 
is one of such cases.

llvm-svn: 297825
2017-03-15 12:02:31 +00:00
George Rimar 49648004ed [ELF] - Detemplate StringTableSection.
StringTableSection was <ELFT> templated previously,

It disallow to de-template code that uses it,
for example LinkerScript<ELFT>::discard uses it as:
if (S == In<ELFT>::ShStrTab)
  error("discarding .shstrtab section is not allowed");

It seems we can try to detemplate some of synthetic sections
and somehow make them available for non-templated calls.
(move out of In<ELFT> struct probably).

Differential revision: https://reviews.llvm.org/D30933

llvm-svn: 297815
2017-03-15 09:32:36 +00:00
George Rimar 22e3e7d165 [ELF] - Make Bss and BssRelRo sections to be synthetic (#3).
That removes CopyRelSection class completely, making
Bss/BssRelRo to be just regular synthetics.

This is splitted from D30541 and polished.
Difference from D30541 that all logic of SharedSymbol
converting to DefinedRegular was removed for now and
probably will be posted as separate patch.

Differential revision: https://reviews.llvm.org/D30892

llvm-svn: 297814
2017-03-15 09:21:29 +00:00
George Rimar 10f74fc10b [ELF] - Detemplate GotPltSection and IgotPltSection sections.
Patch introduces Config->is64Bit() and with help of that detemplates
GotPltSection and IgotPltSection sections

Differential revision: https://reviews.llvm.org/D30944

llvm-svn: 297813
2017-03-15 09:12:56 +00:00