Commit Graph

246 Commits

Author SHA1 Message Date
Rui Ueyama 0cc1483562 Add basic 64-bit SPARC support
Add support for the most common SPARC relocations.
Make DT_PLTGOT point to the PLT on SPARC.
Mark the PLT as executable on SPARC.

This adds a basic test that creates a SPARV9 executable
that invokes the exit system call on OpenBSD.

Patch by Mark Kettenis.

Differential Revision: https://reviews.llvm.org/D34618

llvm-svn: 306565
2017-06-28 17:05:39 +00:00
George Rimar dbe843d602 [ELF] - Do not set st_size field of SHT_UNDEF symbols.
This fixes PR33598.

Size field for undefined symbols is not significant.
Setting it to fixed value, like zero, may be useful though.

For example when we have 2 DSO's, like in this PR, if lower level DSO may
change slightly (in part of some symbol's st_size)  and higher-level DSO is
rebuilt, then tools that monitoring checksum of high level DSO file can notice
it and trigger cascade of some other unnecessary actions. 
If we set st_size to zero, that can be avoided.

Differential revision: https://reviews.llvm.org/D34673

llvm-svn: 306526
2017-06-28 09:51:33 +00:00
Peter Collingbourne dc7936eced ELF: Move section merging before ICF. NFCI.
Differential Revision: https://reviews.llvm.org/D34093

llvm-svn: 305176
2017-06-12 00:00:51 +00:00
George Rimar b4b7b74b5a [ELF] - Fix build bot.
SyntheticSections.cpp:1773:29: error: chosen constructor is explicit in copy-initialization
        CuVectors.push_back({});
                            ^~
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/set:428:14: note: constructor declared here
    explicit set(const value_compare& __comp = value_compare())
             ^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/vector:702:59: note: passing argument to parameter '__x' here
    _LIBCPP_INLINE_VISIBILITY void push_back(value_type&& __x);

llvm-svn: 305054
2017-06-09 04:48:56 +00:00
George Rimar 8666562e89 [ELF] - Make implementation of .gdb index to be more natural for futher paralleling.
This patch reimplements .gdb_index in more natural way,
that makes proccess of switching to multithreaded index building to
be trivial. 

Differential revision: https://reviews.llvm.org/D33552

llvm-svn: 304927
2017-06-07 16:59:11 +00:00
Rafael Espindola 66d98495b0 Delete dead function.
llvm-svn: 304914
2017-06-07 14:24:32 +00:00
George Rimar 0641b8b4d3 [ELF] - Simplify readAddressArea() implementation.
Approach significantly simplifies LLD .gdb_index code and makes it much faster.
Also it should resolve issues, like D33176 tries to address once and forever in a clean way.

LLC binary linking without patch and without --gdb-index: 1,599241063
LLC binary linking without patch and with --gdb-index: 6,064316262
LLC binary linking with patch and with --gdb-index: 4,116792104

Time spent for building gdbindex changes from (6,064316262 - 1,599241063 == 4,465075199)
to (4,116792104- 1,599241063 == 2,517551041).
That is 2,517551041/4,465075199 = 0,564 or about 44% speedup.

Differential revision: https://reviews.llvm.org/D33183

llvm-svn: 304895
2017-06-07 10:52:02 +00:00
Zachary Turner 264b5d9e88 Move Object format code to lib/BinaryFormat.
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.

Differential Revision: https://reviews.llvm.org/D33843

llvm-svn: 304864
2017-06-07 03:48:56 +00:00
Rafael Espindola db5e56f7b2 Store a single Parent pointer for InputSectionBase.
Before InputSectionBase had an OutputSection pointer, but that was not
always valid. For example, if it was a merge section one actually had
to look at MergeSec->OutSec.

This was brittle and caused bugs like the one fixed by r304260.

We now have a single Parent pointer that points to an OutputSection
for InputSection, but to a SyntheticSection for merge sections and
.eh_frame. This makes it impossible to accidentally access an invalid
OutSec.

llvm-svn: 304338
2017-05-31 20:17:44 +00:00
Rafael Espindola 0dc2510762 Simplify. NFC.
llvm-svn: 304330
2017-05-31 19:26:37 +00:00
Rafael Espindola 23db636080 Simplify. NFC.
llvm-svn: 304328
2017-05-31 19:22:01 +00:00
Rafael Espindola b47c6e5cbd Fix a crash.
We would crash if a SHF_LINK_ORDER section pointed to a non
InputSection section. Since those sections are not merged in order,
SHF_LINK_ORDER is pretty meaningless and we can error on that case.

llvm-svn: 304327
2017-05-31 19:09:52 +00:00
Peter Smith ea79b215d6 [ELF] .ARM.exidx sentinel section should use InputSectionDescriptions.
This change converts the writing of the .ARM.exidx sentinel section to use
the InputSectionDescriptions instead of OutputSection::Sections this is in
preparation for the retirement of OutputSection::Sections.
    
Differential Revision: https://reviews.llvm.org/D33500

llvm-svn: 304289
2017-05-31 09:02:21 +00:00
Rafael Espindola 180de970c8 Fix crash when processing relocations in .eh_frame.
This happens when attempting to link shared libraries using exceptions on
MIPS. It requires -z notext because clang generates R_MIPS_64 relocations
inside .eh_frame.
The crash happened because for EhInputSection the OutSec member is null.

Patch by Alexander Richardson!

llvm-svn: 304260
2017-05-31 00:23:23 +00:00
Petr Hosek ffa786f465 [lld][ELF]Add option to make .dynamic read only
The .dynamic section of an ELF almost doesn't need to be written to with
the exception of the DT_DEBUG entry. For several reasons having a read
only .dynamic section would be useful. This change adds the -z keyword
"rodynamic" which forces .dynamic to be read-only. In this case DT_DEBUG
will not be emited.

Patch by Jake Ehrlich

Differential Revision: https://reviews.llvm.org/D33251

llvm-svn: 304024
2017-05-26 19:12:38 +00:00
George Rimar 1ef2e237bf [ELF] - Attemp to fix bot
http://lab.llvm.org:8011/builders/lld-x86_64-darwin13/builds/8549/steps/build_Lld/logs/stdio

llvm-svn: 304016
2017-05-26 18:07:25 +00:00
George Rimar 8684dbaa14 [ELF] - Follow up for r303975. NFCi.
Restore bitwise-or order and fix warning
(was changed by mistake during resolve of conflicts).

llvm-svn: 303976
2017-05-26 12:16:39 +00:00
George Rimar c1a0364cd6 [ELF] - Do not produce duplicate values in .gdb_index's constant pool area.
I found this when builded llc binary using gcc 5.4.1 + LLD.
gcc produces duplicate entries in .debug_gnu_pubtypes section, ex:

UnifyFunctionExitNodes.cpp.o has:
0x0000ac07 EXTERNAL TYPE "std::success_type<void*>"
0x0000ac07 EXTERNAL TYPE "std::success_type<void*>"

clang produces single entry here:
0x0000d291 EXTERNAL TYPE "std::__success_type<void *>"

If we link output from gcc with LLD, that would produce excessive duplicate
entries in .gdb_index constant pool area. That does not seem affect gdb work,
but makes .gdb_index larger than it can be.

I also checked that gold filters out such duplicates too. Patch fixes it.

Differential revision: https://reviews.llvm.org/D32647

llvm-svn: 303975
2017-05-26 12:09:26 +00:00
George Rimar 5f5905eea8 [ELF] - Simplify implementation of constant pool when building .gdb_index
https://sourceware.org/gdb/onlinedocs/gdb/Index-Section-Format.html says:
"A CU vector in the constant pool is a sequence of offset_type values. 
The first value is the number of CU indices in the vector. 
Each subsequent value is the index and symbol attributes of a CU in the CU list."

Previously we keeped 2 values until the end, what was useless. 
Initially was a part of D32647, though it is possible to split out. 
Patch do that.

Differential revision: https://reviews.llvm.org/D33551

llvm-svn: 303973
2017-05-26 12:01:40 +00:00
Rafael Espindola f307d3ea4d Remove dummy cast. NFC.
llvm-svn: 303948
2017-05-26 00:37:39 +00:00
Rafael Espindola a28414d7ec Simplify MipsRldMapSection::writeTo.
It is not clear why a synthetic section wants to use padding defined
in the linker script. The padding is for the space between sections.

It was also missing a test.

llvm-svn: 303812
2017-05-24 22:04:32 +00:00
Rafael Espindola 55b169bf5d Move writeTo to OutputSectionCommand.
This reduces how many times we have to map from OutputSection to
OutputSectionCommand. It is a required step to moving
clearOutputSections earlier.

In order to always use writeTo in OutputSectionCommand we have to call
fabricateDefaultCommands for -r links and move section compression
after it.

llvm-svn: 303784
2017-05-24 18:08:04 +00:00
Rafael Espindola a6465bbb72 Alternative way to detemplate GotSection.
GetSection is a template because write calls relocate.

relocate has two parts. The non alloc code really has to be a
template, as it is looking a raw input file data.

The alloc part is only a template because of getSize.

This patch folds the value of getSize early, detemplates
getRelocTargetVA and splits relocate into a templated non alloc case
and a regular function for the alloc case. This has the nice advantage
of making sure we collect all the information we need for relocations
before getting to InputSection::relocateNonAlloc.

Since we know got is alloc, it can just call the function directly and
avoid the template.

llvm-svn: 303355
2017-05-18 16:45:36 +00:00
George Rimar d8daafd0fb [ELF] - Update for LLVM's r303163 change. NFCi.
llvm-svn: 303164
2017-05-16 12:34:51 +00:00
George Rimar 390242d0e9 [ELF] - Detemplate elf::addSyntheticLocal(). NFC.
llvm-svn: 303155
2017-05-16 10:11:36 +00:00
George Rimar 69b17c35d9 [ELF] - Detemplate access to SymTab, DynSymTab, GnuHashTab. NFC.
Follow up for r303150.

llvm-svn: 303153
2017-05-16 10:04:42 +00:00
George Rimar f45f681609 [ELF] - Detemplate GnuHashTableSection and SymbolTableSection sections.
SymbolTableBaseSection was introduced.

Detemplation of SymbolTableSection should allow to detemplate more things.

Differential revision: https://reviews.llvm.org/D33124

llvm-svn: 303150
2017-05-16 08:53:30 +00:00
Peter Collingbourne 0a2678e9aa ELF: --gdb-index: Change findSection to return an InputSection.
We should only ever expect this function to return a regular
InputSection; I would not expect a function definition to be in a
MergeInputSection or EhInputSection. We were previously crashing
in writeTo if this function returned a section that was not an
InputSection because we do not set OutSec for such sections.

This can happen in practice if a function is defined in an empty
section which shares its offset-in-file with a MergeInputSection,
as in the provided test case.

A better fix for this bug would be to fix the
DWARFUnit::collectAddressRanges() interface to provide section
information (see D33183), but this at least fixes the crash.

Differential Revision: https://reviews.llvm.org/D33176

llvm-svn: 303089
2017-05-15 17:59:21 +00:00
Peter Collingbourne c5bee3212b ELF: --gdb-index: Do not add dead sections to the address area.
Fixes PR33032.

Differential Revision: https://reviews.llvm.org/D33175

llvm-svn: 303088
2017-05-15 17:53:26 +00:00
George Rimar b4081bb0ab [ELF] - Stop support of DF_STATIC_TLS flag.
This reverts changes introduced in r302414 "[ELF] - Set DF_STATIC_TLS flag for i386 target."

Because DF_STATIC_TLS does not look to be used by glibc or anything else.

llvm-svn: 302884
2017-05-12 08:04:58 +00:00
Rafael Espindola 88ab9fb163 Detemplate the got.
This is a bit hackish, but allows for a lot of followup cleanups.

llvm-svn: 302845
2017-05-11 23:26:03 +00:00
Rafael Espindola 5ab1989584 Reduce templating. NFC.
llvm-svn: 302843
2017-05-11 23:16:43 +00:00
Rafael Espindola 895aea6d15 Reduce template usage. NFC.
llvm-svn: 302832
2017-05-11 22:02:41 +00:00
Rafael Espindola b3aa2c9b9e Reduce template usage. NFC.
llvm-svn: 302828
2017-05-11 21:33:30 +00:00
Rafael Espindola 4b1c3696e3 Reduce template usage. NFC.
llvm-svn: 302826
2017-05-11 21:23:38 +00:00
Rui Ueyama 33d903d1b0 Rename parallelFor -> parallelForEachN.
So that it is clear that the function is a wrapper for for_each_n.

llvm-svn: 302718
2017-05-10 20:02:19 +00:00
Rafael Espindola c5b612b8b4 Don't use section names in getFiller. NFC.
This is just faster and avoids using names.

llvm-svn: 302661
2017-05-10 14:01:13 +00:00
George Rimar 1564122b05 [ELF] - Set DF_STATIC_TLS flag for i386 target.
This is PR32437.

DF_STATIC_TLS
If set in a shared object or executable, this flag instructs the 
dynamic linker to reject attempts to load this file dynamically. 
It indicates that the shared object or executable contains code 
using a static thread-local storage scheme. Implementations need 
not support any form of thread-local storage.

Patch checks if IE/LE relocations were used to check if code uses
static model. If so it sets the DF_STATIC_TLS flag.

Differential revision: https://reviews.llvm.org/D32354

llvm-svn: 302414
2017-05-08 10:24:38 +00:00
Rafael Espindola a8a1a4fc30 Avoid empty .eh_frame sections.
Strip on OpenBSD does not correctly handle an empty .eh_frame section
and produces broken binaries in that case. Currently lld creates such
an empty .eh_frame section, despite the fact that the OpenBSD crtend.o
explicitly inserts a terminator. The Linux LSB "standard":

https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/ehframechpt.html#EHFRAME

explicitly says that

    The .eh_frame section shall contain 1 or more Call Frame Information (CFI) records.

This diff includes a test that specifically tests the issue I'm seeing
on OpenBSD.

Patch by Mark Kettenis!

llvm-svn: 301931
2017-05-02 15:45:31 +00:00
Rui Ueyama bd27849e4b Rename RPath Rpath for consistency. NFC.
For an option -foo-bar-baz, we have Config->FooBarBaz. Since -rpath is
-rpath and not -r-path, it should be Config->Rpath instead Config->RPath.

llvm-svn: 301759
2017-04-29 23:06:43 +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
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
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
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
James Henderson d983180778 Revert r299635 because it exposed a latent bug.
llvm-svn: 299655
2017-04-06 15:22:58 +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
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 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 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