Commit Graph

2893 Commits

Author SHA1 Message Date
Petr Hosek 2f50fef095 [ELF] Shared libraries should have entry point
Shared libraries should have entry set following the same rules as for
regular binaries. The only difference is that in case the default entry
point (_start or __start) isn't found (unless it was set explicitly), we
shouldn't give a warning as in case of regular binaries.

Differential Revision: https://reviews.llvm.org/D27497

llvm-svn: 288878
2016-12-07 02:26:16 +00:00
George Rimar a2a32c2cc8 [ELF] - Teach LLD to recognize PT_OPENBSD_BOOTDATA
Minor patch to fix PR31288

OpenBSD commit:
d39116912b

Differential revision: https://reviews.llvm.org/D27458

llvm-svn: 288832
2016-12-06 17:57:42 +00:00
Rafael Espindola 074ba93ceb Don't print empty PT_LOAD.
If we do, the freebsd dynamic linker tries to call mmap with a size 0,
which fails.

It is hard to avoid creating them when linker scripts are used, so we
just delete empty PT_LOADs at the end.

llvm-svn: 288808
2016-12-06 13:43:34 +00:00
Rafael Espindola e004d4bfc2 Don't crash trying to write an 0 addend.
For preemptable symbols the dynamic linker does all the work. Trying
to compute the addend is at best wasteful and can also lead to crashes
in cases of programs that uses tls but doesn't define any tls
variables.

llvm-svn: 288803
2016-12-06 12:19:24 +00:00
Rafael Espindola 43c3cb7786 Make the test a bit more strict. NFC.
llvm-svn: 288802
2016-12-06 12:15:12 +00:00
Rafael Espindola d207c37806 Test only the relevant bits.
This test only needs to test the Type (SharedObject), the address of
the first PT_LOAD and the presence of PT_DYNAMIC.

llvm-svn: 288719
2016-12-05 22:27:21 +00:00
Rafael Espindola d6b42ee404 Don't check the symbol values is this test.
It only needs to find how many are local.

llvm-svn: 288716
2016-12-05 22:16:32 +00:00
Rafael Espindola 7b4dd875df Don't check symbol value in this test.
llvm-svn: 288704
2016-12-05 21:02:45 +00:00
Rafael Espindola 35ac8bab7b Don't check the symbol value in this test.
llvm-svn: 288702
2016-12-05 20:56:40 +00:00
Rafael Espindola c5b3334124 Don't check the symbol values.
This test is just about which symbols are in which table.

llvm-svn: 288701
2016-12-05 20:53:11 +00:00
Rafael Espindola fc4ddbbe8f Simplify test. NFC.
llvm-svn: 288700
2016-12-05 20:49:16 +00:00
Rafael Espindola b4e61e9dd0 Make test test what it should be testing.
Looks like the second section in this test was lost along the way.

llvm-svn: 288699
2016-12-05 20:42:58 +00:00
Rui Ueyama 44da9decb5 Include object file name to an error message.
llvm-svn: 288686
2016-12-05 18:40:14 +00:00
Eugene Leviant 2a942c4b45 [ELF] Print file:line for unknown PHDR error
Differential revision: https://reviews.llvm.org/D27335

llvm-svn: 288678
2016-12-05 16:38:32 +00:00
Adhemerval Zanella a47ba192dc ELF/AArch64: Fix R_AARCH64_LDST16_ABS_LO12_NC mask
The relocation R_AARCH64_LDST16_ABS_LO12_NC should set a ld/st
immediate value to bits [11:1] not [11:2].  This patches fixes it
and adds a testcase for regression.

With this fix all the faulty tests on test-suite (clavm, lencod,
and trimaran) pass.

llvm-svn: 288670
2016-12-05 14:15:44 +00:00
Rui Ueyama 5cb712ed3c Simplify ICF alignment handling.
llvm-svn: 288630
2016-12-05 01:31:39 +00:00
Rafael Espindola 61d052d725 Don't discard .L symbol with -r.
They might be used by relocations.

Fixes pr31252.

llvm-svn: 288617
2016-12-04 08:34:17 +00:00
Rafael Espindola 27004d336f Ignone SHF_INFO_LINK.
Some elf producers (dtrace) put this flag in relocation sections and
some (MC) don't. If we don't ignore the flag we end up with multiple
relocation sections poiting to the same section, which we don't
support.

llvm-svn: 288585
2016-12-03 15:26:18 +00:00
George Rimar 1b3d34a298 [ELF] - Implemented R_386_16 and R_386PC16 relocations
A program or object file using R_386_8, R_386_16, R_386_PC16 or R_386_PC8
relocations is not conformant to latest ABI. The R_386_16, and R_386_8
relocations truncate the computed value to 16 - bits and 8 - bits
respectively. R_386_PC16 and R_386_16 are used by some
applications, for example by FreeBSD loaders.

Previously we did not take addend in account for these relocation,
counting it as 0, what is wrong and was a reason of hangs.

This patch needed for example for FreeBSD pmbr (protective mbr).

Differential revision: https://reviews.llvm.org/D27303

llvm-svn: 288581
2016-12-03 07:30:30 +00:00
George Rimar 40c28c7f9a [ELF] - Change the way how we compute offsets for binary output.
Binary output feature is a bit confuzing. bfd and gold output differs a lot sometimes,
though it is important for FreeBSD mbr loaders.

Patch change the way how we compute file offsets for binary output.
This fixes PR31196.

Previously offsets were calculated basing on offsets and addresses of sections
from the same loads:
if (Sec == First)
  return alignTo(Off, Target->MaxPageSize, Sec->Addr);
return First->Offset + Sec->Addr - First->Addr;

bfd assigns offsets for each section to VA - MinVA:
https://github.com/redox-os/binutils-gdb/blob/master/bfd/binary.c#L27
https://github.com/redox-os/binutils-gdb/blob/master/bfd/binary.c#L255 
(LMA == VA usually)

This patch for now just stops creating phdrs for binary output. 
An effect from this that no any additional calculation for offset is performed:

uintX_t getFileAlignment(uintX_t Off, OutputSectionBase *Sec) {
OutputSectionBase *First = Sec->FirstInPtLoad;
// If the section is not in a PT_LOAD, we have no other constraint.
if (!First)
  return Off; //**First is always null, condition always happens**

That is enough now with combination of another patch to generate output
that is similar to what bfd produce for mbr loader.

Differential revision: https://reviews.llvm.org/D27341

llvm-svn: 288580
2016-12-03 07:23:30 +00:00
George Rimar d250618c3e [ELF] - Disable relro when -omagic specified.
--omagic is an option to create old-fashioned executables in which
.text segments are writable. Today, the option is still in use to
create special-purpose programs such as boot loaders. It doesn't
make sense to create PT_GNU_RELRO for such executables.

DIfferential revision: https://reviews.llvm.org/D27297

llvm-svn: 288579
2016-12-03 07:09:28 +00:00
Rui Ueyama 83ec681a5c Removed a wrong assertion about non-colorable sections.
The assertion asserted that colorable sections can never have
a reference to non-colorable sections, but that was simply wrong.
They can have references to non-colorable sections. If that's the
case, referenced sections must be the same in terms of pointer
comparison.

llvm-svn: 288511
2016-12-02 17:23:58 +00:00
Rafael Espindola 5708b2f8a6 Ignore R_X86_64_NONE.
It looks like the way dtrace works is

* The user creates .o files that reference magical symbol names.
* dtrace reads those files, collecs the info it needs and changes the
  relocation to R_X86_64_NONE expecting the linker to ignore them.

llvm-svn: 288485
2016-12-02 08:00:09 +00:00
Rui Ueyama 27498b5dd5 Fix a bug in ICF involving COFF associative sections.
Associative sections are sections that need to be linked if their associated
sections are linked. Associative sections are used to append auxiliary data
such as debug info.

Previously, we compared all associative sections when comparing two comdat
sections. Because usually assocative sections are not mergeable sections,
we missed a lot of mergeable sections. MSVC linker doesn't seem to check
the identity of associative sections.

This patch makes LLD to ignore associative sections when doing ICF.

llvm-svn: 288483
2016-12-02 07:46:12 +00:00
Rafael Espindola 103fc28961 Add a test documenting how we handle addends on Elf_Rela.
llvm-svn: 288477
2016-12-02 04:20:47 +00:00
Rafael Espindola 858c092daa Allow duplicated abs symbols with the same value.
This is a fairly reasonable bfd extension since there is one obvious value.

dtrace depends on this feature as it creates multiple absolute
symbols with the same value.

llvm-svn: 288461
2016-12-02 02:58:21 +00:00
Rafael Espindola f4ff80c128 Write the addent to got entries when using Elf_Rel.
llvm-svn: 288451
2016-12-02 01:57:24 +00:00
Rui Ueyama c5cb737584 Dump Codeview type information correctly.
llvm-svn: 288298
2016-12-01 01:22:48 +00:00
Peter Smith de3e73880e [ELF] Add support for static TLS to ARM
The module index dynamic relocation R_ARM_DTPMOD32 is always 1 for an
executable. When static linking and when we know that we are not a shared
object we can resolve the module index relocation statically.
    
The logic in handleNoRelaxTlsRelocation remains the same for Mips as it
has its own custom GOT writing code. For ARM we add the module index
relocation to the GOT when it can be resolved statically.
    
In addition the type of the RelExpr for the static resolution of TlsGotRel
should be R_TLS and not R_ABS as we need to include the size of
the thread control block in the calculation.
    
Addresses the TLS part of PR30218.

Differential revision: https://reviews.llvm.org/D27213

llvm-svn: 288153
2016-11-29 16:23:50 +00:00
George Rimar 9b3ae73fc8 [ELF] - Disable emiting multiple output sections when merging is disabled.
When -O0 is specified, we do not do section merging.
Though before this patch several sections were generated instead
of single, what is useless.

Differential revision: https://reviews.llvm.org/D27041

llvm-svn: 288151
2016-11-29 16:11:09 +00:00
George Rimar 3fb5a6dc9e [ELF] - Add support of proccessing of the rest allocatable synthetic sections from linkerscript.
This change continues what was started by D27040
Now all allocatable synthetics should be available from script side.

Differential revision: https://reviews.llvm.org/D27131

llvm-svn: 288150
2016-11-29 16:05:27 +00:00
Simon Atanasyan 160bf723f5 [ELF][MIPS] Make stable an order of GOT page address entries
llvm-svn: 288137
2016-11-29 13:26:04 +00:00
Simon Atanasyan 198dd205e6 [ELF][MIPS] Add new check to the test case in attempt to investigate Windows build-bot failure
llvm-svn: 288132
2016-11-29 11:19:47 +00:00
Simon Atanasyan 9fae3b8a2c [ELF][MIPS] Do not change MipsGotSection state in the getPageEntryOffset method
The MipsGotSection::getPageEntryOffset calculates index of GOT entry
with a "page" address. Previously this method changes the state
of MipsGotSection because it modifies PageIndexMap field. That leads
to the unpredictable results if getPageEntryOffset called from multiple threads.

The patch makes getPageEntryOffset constant. To do so it calculates GOT
entry index but does not update PageIndexMap field. Later in the
MipsGotSection::writeTo method linker calculates "page" addresses and
writes them to the output.

llvm-svn: 288129
2016-11-29 10:23:56 +00:00
Simon Atanasyan 80f3d9ce93 [ELF][MIPS] Fix calculation of GOT "page address" entries number
If output section which referenced by R_MIPS_GOT_PAGE or R_MIPS_GOT16
relocations is small (less that 0x10000 bytes) and occupies two adjacent
0xffff-bytes pages, current formula gives incorrect number of required "page"
GOT entries. The problem is that in time of calculation we do not know
the section address and so we cannot calculate number of 0xffff-bytes
pages exactly.

This patch fix the formula. Now it gives a correct number of pages in
the worst case when "small" section intersects 0xffff-bytes page
boundary. From the other side, sometimes it adds one more redundant GOT
entry for each output section. But usually number of output sections
referenced by GOT relocations is small.

llvm-svn: 288127
2016-11-29 10:23:46 +00:00
George Rimar 595a763f38 [ELF] - Implemented -N (-omagic) command line option.
-N (-omagic)
  Set the text and data sections to be readable and writable. 
  Also, do not page-align the data segment.

Differential revision: https://reviews.llvm.org/D26888

llvm-svn: 288123
2016-11-29 09:43:51 +00:00
Eugene Leviant 84569e6caa [ELF] Refactor target error messages
Differential revision: https://reviews.llvm.org/D27097

llvm-svn: 288114
2016-11-29 08:05:44 +00:00
Rafael Espindola 5498ba38df Add a test.
It would have found a missing case in another patch.

llvm-svn: 288101
2016-11-29 03:30:07 +00:00
George Rimar 1642c5d871 [ELF] - Do not put non exec sections first when -no-rosegment
That unifies handling cases when we have SECTIONS and when
-no-rosegment is given in compareSectionsNonScript()

Now Config->SingleRoRx is used for check, testcase is provided.

llvm-svn: 288022
2016-11-28 10:26:21 +00:00
George Rimar 63bf011003 [ELF] - Implemented -no-rosegment.
--no-rosegment: Do not put read-only non-executable sections in their own segment

Differential revision: https://reviews.llvm.org/D26889

llvm-svn: 288020
2016-11-28 10:05:20 +00:00
Eugene Leviant ed30ce7ae4 [ELF] Print file:line for 'undefined section' errors
Differential revision: https://reviews.llvm.org/D27108

llvm-svn: 288019
2016-11-28 09:58:04 +00:00
Rafael Espindola 8e67000f1a Always create a PT_ARM_EXIDX if needed.
Unfortunatelly PT_ARM_EXIDX is special. There is no way to create it
from linker scripts, so we have to create it even if PHDRS is used.

This matches bfd and is required for the lld output to survive bfd's strip.

llvm-svn: 288012
2016-11-28 00:40:21 +00:00
Rafael Espindola 5fcc99c27d Also skip regular symbol assignment at the start of a script.
Unfortunatelly some scripts look like

kernphys = ...
. = ....

and the expectation in that every orphan section is after the
assignment.

llvm-svn: 287996
2016-11-27 09:44:45 +00:00
Rafael Espindola 7fe4ec9b3a Don't put an orphan before the first . assignment.
This is an horrible special case, but seems to match bfd's behaviour
and is important for avoiding placing an orphan section before the
expected start of the file.

llvm-svn: 287994
2016-11-27 07:39:45 +00:00
Rafael Espindola f93b8c29c8 Create sections with just assignments as STT_NOBITS.
This matches the behaviour of bfd ld. Using 0 was causing problems
with strip, which would remove these sections.

llvm-svn: 287969
2016-11-26 06:55:35 +00:00
Rui Ueyama d873e3a694 Fix buildbots.
llvm-svn: 287952
2016-11-25 20:42:39 +00:00
Rui Ueyama 8c8818a58c Support -color-diagnostics={auto,always,never}.
-color-diagnostics=auto is default because that's the same as
Clang's default. When color is enabled, error or warning messages
are colored like this.

  error:
  <bold>ld.lld</bold> <red>error:</red> foo.o: no such file

  warning:
  <bold>ld.lld</bold> <magenta>warning:</magenta> foo.o: no such file

Differential Revision: https://reviews.llvm.org/D27117

llvm-svn: 287949
2016-11-25 20:27:32 +00:00
Eugene Leviant ab024a353f [ELF] Refactor getDynRel to print error location
Differential revision: https://reviews.llvm.org/D27055

llvm-svn: 287915
2016-11-25 08:56:36 +00:00
George Rimar 11992c86d9 [ELF] - Add support for access to most of synthetic sections from linkerscript.
This is important for cases like:

  .sdata        : {
    *(.got.plt .got)
...
  }

That was not supported before as there was no way to get access to 
synthetic sections from script.

More details on review page.

Differential revision: https://reviews.llvm.org/D27040

llvm-svn: 287913
2016-11-25 08:05:41 +00:00
Rui Ueyama 26081caf48 Use toString() to report incompatible files.
llvm-svn: 287901
2016-11-24 20:59:44 +00:00