Commit Graph

51 Commits

Author SHA1 Message Date
Vlad Tsyrklevich 5874a28ac5 Revert "Reland [ELF] Loose a condition for relocation with a symbol"
This reverts commit r366686 as it appears to be causing buildbot
failures on sanitizer-x86_64-linux-android and sanitizer-x86_64-linux.

llvm-svn: 366708
2019-07-22 17:48:53 +00:00
Nikola Prica 0166cff09b Reland [ELF] Loose a condition for relocation with a symbol
This patch was not the reason of the buildbot failure.

Deleted code was introduced as a work around for a bug in the gold linker
(http://sourceware.org/PR16794). Test case that was given as a reason for
this part of code, the one on previous link, now works for the gold.
This condition is too strict and when a code is compiled with debug info
it forces generation of numerous relocations with symbol for architectures
that do not have relocation addend.

Reviewers: arsenm, espindola

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D64327

llvm-svn: 366686
2019-07-22 13:07:01 +00:00
Nikola Prica bbfa4cf70b Revert "[ELF] Loose a condition for relocation with a symbol"
This reverts commit 8507eca1647118e73435b0ce1de8a1952a021d01.

Reveting due to some suspicious failurse in santizer-x86_64-linux.

llvm-svn: 365685
2019-07-10 18:58:05 +00:00
Nikola Prica fb163b4b20 [ELF] Loose a condition for relocation with a symbol
Deleted code was introduced as a work around for a bug in the gold linker
(http://sourceware.org/PR16794). Test case that was given as a reason for
this part of code, the one on previous link, now works for the gold.
This condition is too strict and when a code is compiled with debug info
it forces generation of numerous relocations with symbol for architectures
that do not have relocation addend.

Reviewers: arsenm, espindola

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D64327

llvm-svn: 365618
2019-07-10 11:17:48 +00:00
Rafael Espindola a29971faeb Add initial support for R_386_GOT32X.
This adds it only for movl mov@GOT(%reg), %reg.

llvm-svn: 274678
2016-07-06 21:19:11 +00:00
Michael Kuperstein a3b79dd783 [ELF] elfiamcu triple should imply e_machine == EM_IAMCU
Differential Revision: http://reviews.llvm.org/D14109

llvm-svn: 252043
2015-11-04 11:21:50 +00:00
Daniel Jasper 41de8027b1 Revert r240302 ("Bring r240130 back.").
This causes errors like:

  ld: error: blah.o: requires dynamic R_X86_64_PC32 reloc against '' which
  may overflow at runtime; recompile with -fPIC
  blah.cc:function f(): error: undefined reference to ''
  blah.o:g(): error: undefined reference to ''

I have not yet come up with an appropriate reproduction.

llvm-svn: 240394
2015-06-23 11:31:32 +00:00
Rafael Espindola 2d6bae2e09 Bring r240130 back.
Now that pr23900 is fixed, we can bring it back with no changes.

Original message:

Make all temporary symbols unnamed.

What this does is make all symbols that would otherwise start with a .L
(or L on MachO) unnamed.

Some of these symbols still show up in the symbol table, but we can just
make them unnamed.

In order to make sure we produce identical results when going thought assembly,
all .L (not just the compiler produced ones), are now unnamed.

Running llc on llvm-as.opt.bc, the peak memory usage goes from 208.24MB to
205.57MB.

llvm-svn: 240302
2015-06-22 17:52:52 +00:00
Nico Weber 67e715ff7d Revert 240130, it caused crashes (repro in PR23900).
llvm-svn: 240193
2015-06-19 23:43:47 +00:00
Rafael Espindola 284a750c5f Make all temporary symbols unnamed.
What this does is make all symbols that would otherwise start with a .L
(or L on MachO) unnamed.

Some of these symbols still show up in the symbol table, but we can just
make them unnamed.

In order to make sure we produce identical results when going thought assembly,
all .L (not just the compiler produced ones), are now unnamed.

Running llc on llvm-as.opt.bc, the peak memory usage goes from 208.24MB to
205.57MB.

llvm-svn: 240130
2015-06-19 12:16:55 +00:00
Rafael Espindola 75d5b5495f Fix the interpretation of a 0 st_name.
The ELF spec is very clear:

-----------------------------------------------------------------------------
If the value is non-zero, it represents a string table index that gives the
symbol name. Otherwise, the symbol table entry has no name.
--------------------------------------------------------------------------

In particular, a st_name of 0 most certainly doesn't mean that the symbol has
the same name as the section.

llvm-svn: 238899
2015-06-03 05:14:22 +00:00
Rafael Espindola 10f3de6889 Update tests to not be as dependent on section numbers.
Many of these predate llvm-readobj. With elf-dump we had to match
a relocation to symbol number and symbol number to symbol name or
section number.

llvm-svn: 235015
2015-04-15 15:59:37 +00:00
Rafael Espindola bdfbde56e0 Reorganize the x86 ELF relocation selection logic.
The main differences are:

* Split in 32 and 64 bit functions.
* First switch on the Modifier so that we have only one non fully covered
  switch.
* Map the fixup kind first to a x86_64 (or i386) specific enum, to make
  it easy to handle cases like X86::reloc_riprel_4byte_movq_load.
* Switch on IsPCRel last, which reduces code duplication.

Fixes pr22308.

llvm-svn: 232837
2015-03-20 19:48:54 +00:00
Rafael Espindola 38438bae21 Handle X86::reloc_riprel_4byte in 32 bits mode.
We can get there with .code64.

Fixes pr22349.

llvm-svn: 232651
2015-03-18 17:33:40 +00:00
Joerg Sonnenberger b6956e113a Support @PLT loads on 32bit x86.
llvm-svn: 226182
2015-01-15 17:59:02 +00:00
Rafael Espindola 3d082fa507 Fix pr19645.
The fix itself is fairly simple: move getAccessVariant to MCValue so that we
replace the old weak expression evaluation with the far more general
EvaluateAsRelocatable.

This then requires that EvaluateAsRelocatable stop when it finds a non
trivial reference kind. And that in turn requires the ELF writer to look
harder for weak references.

Last but not least, this found a case where we were being bug by bug
compatible with gas and accepting an invalid input. I reported pr19647
to track it.

llvm-svn: 207920
2014-05-03 19:57:04 +00:00
Rafael Espindola b1b49789d0 Work around gold bug http://sourceware.org/PR16794.
llvm-svn: 205416
2014-04-02 12:15:20 +00:00
Rafael Espindola 5904e12bfa Completely rewrite ELFObjectWriter::RecordRelocation.
I started trying to fix a small issue, but this code has seen a small fix too
many.

The old code was fairly convoluted. Some of the issues it had:

* It failed to check if a symbol difference was in the some section when
  converting a relocation to pcrel.
* It failed to check if the relocation was already pcrel.
* The pcrel value computation was wrong in some cases (relocation-pc.s)
* It was missing quiet a few cases where it should not convert symbol
  relocations to section relocations, leaving the backends to patch it up.
* It would not propagate the fact that it had changed a relocation to pcrel,
  requiring a quiet nasty work around in ARM.
* It was missing comments.

llvm-svn: 205076
2014-03-29 06:26:49 +00:00
David Woodhouse adfc885997 [x86] Support R_386_PC8, R_386_PC16 and R_X86_64_PC8
llvm-svn: 198763
2014-01-08 12:58:40 +00:00
Rafael Espindola 4f60a38f18 Change how we iterate over relocations on ELF.
For COFF and MachO, sections semantically have relocations that apply to them.
That is not the case on ELF.

In relocatable objects (.o), a section with relocations in ELF has offsets to
another section where the relocations should be applied.

In dynamic objects and executables, relocations don't have an offset, they have
a virtual address. The section sh_info may or may not point to another section,
but that is not actually used for resolving the relocations.

This patch exposes that in the ObjectFile API. It has the following advantages:

* Most (all?) clients can handle this more efficiently. They will normally walk
all relocations, so doing an effort to iterate in a particular order doesn't
save time.

* llvm-readobj now prints relocations in the same way the native readelf does.

* probably most important, relocations that don't point to any section are now
visible. This is the case of relocations in the rela.dyn section. See the
updated relocation-executable.test for example.

llvm-svn: 182908
2013-05-30 03:05:14 +00:00
Nico Rieck ba848e3bca Replace coff-/elf-dump with llvm-readobj
llvm-svn: 179361
2013-04-12 04:06:46 +00:00
Rafael Espindola 7e0a793183 Handle reloc_signed_4byte in here. Not doing so was a regression from my
previous commit. It is strange that we see it in 32 bits. We already
have a fixme about it.

llvm-svn: 146273
2011-12-09 19:57:29 +00:00
Rafael Espindola 0a7f336475 Handle the case of the magical _GLOBAL_OFFSET_TABLE_ showing up in a
symbol difference. This matches gas behavior and fixes PR11513.

We still don't handle _GLOBAL_OFFSET_TABLE_ in data sections.

llvm-svn: 146238
2011-12-09 03:03:58 +00:00
Rafael Espindola 9bc32a96be print st_shndx with the correct number of bits.
llvm-svn: 136880
2011-08-04 15:50:13 +00:00
Rafael Espindola 9528995e3f print st_other with the correct number of bits.
llvm-svn: 136877
2011-08-04 15:38:19 +00:00
Rafael Espindola 96df560ce1 print st_type with the correct number of bits.
llvm-svn: 136875
2011-08-04 15:24:00 +00:00
Rafael Espindola 79ef75dc49 Print st_bind with the correct number of bits.
llvm-svn: 136874
2011-08-04 15:10:35 +00:00
Rafael Espindola 1848231ad1 Print r_sym with the correct number of bits.
llvm-svn: 136873
2011-08-04 14:48:27 +00:00
Rafael Espindola 260af5cef6 Print r_type with the correct number of bits.
llvm-svn: 136872
2011-08-04 14:39:30 +00:00
Rafael Espindola 1b282e7e49 Another counter goes decimal.
llvm-svn: 136871
2011-08-04 14:27:46 +00:00
Rafael Espindola 65c559c5fb Change anther counter to decimal.
llvm-svn: 136870
2011-08-04 14:01:03 +00:00
Rafael Espindola cad9e7f094 Don't print a counter in hex.
llvm-svn: 136869
2011-08-04 13:39:15 +00:00
Nick Lewycky 34fa1684e7 Add support for @GOTPTOFF in i386 mode.
llvm-svn: 132643
2011-06-04 17:38:07 +00:00
Rafael Espindola 9a1a34b105 Update tests
llvm-svn: 129116
2011-04-07 23:51:25 +00:00
Rafael Espindola 1557fd6d39 Write the section table and the section data in the same order that
gun as does. This makes it a lot easier to compare the output of both
as the addresses are now a lot closer.

llvm-svn: 127972
2011-03-20 18:44:20 +00:00
Rafael Espindola af5ab7ad26 Test for push being relaxed.
llvm-svn: 122124
2010-12-18 01:16:59 +00:00
Rafael Espindola 9f75d5df0b Behave a bit more like gnu as and use the symbol (instead of the section)
for any relocation to a symbol defined in a tls section.

llvm-svn: 120121
2010-11-24 21:57:39 +00:00
Rafael Espindola 708ac4d6ad Relocate with the symbol if the relocation is of kind NTPOFF.
Patch by David Meyer, I added the test.

llvm-svn: 120104
2010-11-24 19:23:50 +00:00
Rafael Espindola 26cb15a549 Handle PCRel relocations with absolute values. Fixes PR8656.
llvm-svn: 119917
2010-11-21 00:48:25 +00:00
Rafael Espindola e8f08be11c Implement DTPOFF.
llvm-svn: 117546
2010-10-28 14:48:59 +00:00
Rafael Espindola 6f23eb380d Implement TLSLDM.
llvm-svn: 117544
2010-10-28 14:37:09 +00:00
Rafael Espindola b3b49bbc39 Implement VK_GOTNTPOFF and switch RelocNeedsGOT to use VariantKind.
llvm-svn: 117543
2010-10-28 14:22:44 +00:00
Rafael Espindola f8537165bd Add support for R_386_TLS_GD, R_386_TLS_LE_32, R_386_TLS_IE and R_386_TLS_LE.
llvm-svn: 117494
2010-10-27 21:23:52 +00:00
Jason W Kim e8b3711ae9 Fixing r116753 r116756 r116777
The failures in r116753 r116756 were caused by a python issue -
Python likes to append 'L' suffix to stringified numbers if the number
is larger than a machine int. Unfortunately, this causes a divergence of
behavior between 32 and 64 bit python versions.

I re-crafted elf-dump/common_dump to take care of these issues by:

1. always printing 0x (makes for easy sed/regex)
2. always print fixed length (exactly 2 + numBits/4 digits long)
   by mod ((2^numBits) - 1)
3. left-padded with '0'

There is a residual common routine that is also used by
macho-dump (dataToHex) , so I left the 'section_data' test values alone.

llvm-svn: 116823
2010-10-19 17:39:10 +00:00
Eric Christopher eac5e381cc Speculatively revert 116753 and 116756 to attempt to fix the bots.
llvm-svn: 116777
2010-10-19 00:19:49 +00:00
Jason W Kim eae048885d Changed elf-dump to output hex format by default.
Also updated tests. 

llvm-svn: 116753
2010-10-18 21:32:41 +00:00
Rafael Espindola fba9f74932 Implement R_386_GOT32.
llvm-svn: 116744
2010-10-18 20:47:21 +00:00
Rafael Espindola 0a5314fdb3 Relocate with .bss instead of using the symbol. Matches gas behavior.
llvm-svn: 116741
2010-10-18 20:25:33 +00:00
Rafael Espindola e3dc9e2ea1 Produce ELF::R_386_GOTPC relocations.
llvm-svn: 116728
2010-10-18 18:36:12 +00:00
Rafael Espindola 3521f8467d Produce a R_386_PLT32 when needed. Moved the default cases of switches to the
start for consistency.

llvm-svn: 116715
2010-10-18 16:58:03 +00:00