Commit Graph

433 Commits

Author SHA1 Message Date
Simon Atanasyan
ce538c7834 [elf2yaml][ELF] Move Info field to the RelocationSection structure. This
field represents ELF section header sh_info field and does not have any
sense for regular sections. Its interpretation depends on section type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209801 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-29 11:05:31 +00:00
Simon Atanasyan
84a0dc323d [YAML] Add an optional argument EnumMask to the yaml::IO::bitSetCase().
Some bit-set fields used in ELF file headers in fact contain two parts.
The first one is a regular bit-field. The second one is an enumeraion.
For example ELF header `e_flags` for MIPS target might contain the
following values:

Bit-set values:

  EF_MIPS_NOREORDER = 0x00000001
  EF_MIPS_PIC       = 0x00000002
  EF_MIPS_CPIC      = 0x00000004
  EF_MIPS_ABI2      = 0x00000020

Enumeration:

  EF_MIPS_ARCH_32   = 0x50000000
  EF_MIPS_ARCH_64   = 0x60000000
  EF_MIPS_ARCH_32R2 = 0x70000000
  EF_MIPS_ARCH_64R2 = 0x80000000

For printing bit-sets we use the `yaml::IO::bitSetCase()`. It does not
support bit-set/enumeration combinations and prints too many flags from
an enumeration part. This patch fixes this problem. New method
`yaml::IO::maskedBitSetCase()` handle "enumeration" part of bitset
defined by provided mask.

Patch reviewed by Nick Kledzik and Sean Silva.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209504 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-23 08:07:09 +00:00
Kevin Enderby
b38059ab25 Update MachOObjectFile::getSymbolAddress so it returns UnknownAddressOrSize
for undefined symbols, so it matches what COFFObjectFile::getSymbolAddress
does.  This allows llvm-nm to print spaces instead of 0’s for the value
of undefined symbols in Mach-O files.

To make this change other uses of MachOObjectFile::getSymbolAddress
are updated to handle when the Value is returned as UnknownAddressOrSize.
Which is needed to keep two of the ExecutionEngine tests working for example.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209253 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-20 23:04:47 +00:00
Kevin Enderby
95aa960b71 Revert r209235 as it broke two tests:
Failing Tests (2):
	    LLVM :: ExecutionEngine/MCJIT/stubs-sm-pic.ll
	    LLVM :: ExecutionEngine/MCJIT/stubs.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209236 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-20 21:10:15 +00:00
Kevin Enderby
e3f74564ff Update MachOObjectFile::getSymbolAddress so it returns UnknownAddressOrSize
for undefined symbols.  Allowing llvm-nm to print spaces instead of 0’s for
the value of undefined symbols in Mach-O files.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209235 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-20 20:32:18 +00:00
Simon Atanasyan
6943f62a41 [Mips] Add more relocation types and MIPS specific e_flags constants.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209201 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-20 09:27:49 +00:00
Kevin Enderby
86ad7b70cb Implement MachOObjectFile::isSectionData() and MachOObjectFile::isSectionBSS
so that llvm-size will total up all the sections in the Berkeley format.  This
allows for rough categorizations for Mach-O sections.  And allows the total of
llvm-size’s Berkeley and System V formats to be the same.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209158 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-19 20:36:02 +00:00
Craig Topper
6ec950549b Remove last uses of OwningPtr from llvm. As far as I can tell these method versions are not used by lldb, lld, or clang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209103 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-18 21:55:38 +00:00
Simon Atanasyan
19ab8f850f [yaml2obj][ELF] Add an optional Size field to the YAML section declaration.
Now the only method to configure ELF section's content and size is to assign
a hexadecimal string to the `Content` field. Unfortunately this way is
completely useless when you need to declare a really large section.

To solve this problem this patch adds one more optional field `Size`
to the `RawContentSection` structure. When yaml2obj generates an ELF file
it uses the following algorithm:
1. If both `Content` and `Size` fields are missed create an empty section.
2. If only `Content` field is missed take section length from the `Size`
   field and fill the section by zero.
3. If only `Size` field is missed create a section using data from
   the `Content` field.
4. If both `Content` and `Size` fields are provided validate that the `Size`
   value is not less than size of `Content` data. Than take section length
   from the `Size`, fill beginning of the section by `Content` and the rest
   by zero.

Examples
--------
* Create a section 0x10000 bytes long filled by zero
  Name: .data
  Type: SHT_PROGBITS
  Flags: [ SHF_ALLOC ]
  Size: 0x10000

* Create a section 0x10000 bytes long starting from 'CA' 'FE' 'BA' 'BE'
  Name: .data
  Type: SHT_PROGBITS
  Flags: [ SHF_ALLOC ]
  Content: CAFEBABE
  Size: 0x10000

The patch reviewed by Michael Spencer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208995 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-16 16:01:00 +00:00
Simon Atanasyan
650c53fe2a [obj2yaml][ELF] Do not print empty Link and Info fields for ELF sections.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208905 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-15 18:04:02 +00:00
Kevin Enderby
14963a696b Teach llvm-nm to know about fat archives (aka MachOUniversal files
containing archives).  First step as other tools will be updated next.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208812 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-14 21:18:50 +00:00
Simon Atanasyan
b8236e532a [obj2yaml] Support ELF input format in the obj2yaml tool.
The ELF header e_flags field in the MIPS related test cases handled
incorrectly. The obj2yaml prints too many flags. I will fix that in the
next patches.

The patch reviewed by Michael Spencer and Sean Silva.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208752 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-14 05:07:47 +00:00
Lang Hames
b572bc1ccf [RuntimeDyld] Add support for MachO __jump_table and __pointers sections, and
SECTDIFF relocations on 32-bit x86.

This fixes several of the MCJIT regression test failures that show up on 32-bit
builds.

<rdar://problem/16886294>



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208635 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-12 21:39:59 +00:00
Simon Atanasyan
d92c843b2e [yaml2obj] Support ELF x86 relocations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208228 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-07 17:06:38 +00:00
Simon Atanasyan
e26759bd66 [ELFYAML] Group ELF header falgs to target specific blocks. Handle flags
which are corresponding to the current target read from the ELF file.

This fix cannot be tested until obj2yaml does not support ELF format.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207905 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-03 11:39:50 +00:00
Simon Atanasyan
e6982bfe51 [ELFYAML] Add more SHT_xxx flags to the YAML section type mapping.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207904 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-03 11:39:44 +00:00
Hans Wennborg
a8febf2283 ELFObjectWriter: deduplicate suffices in strtab
We already do this for shstrtab, so might as well do it for strtab. This
extracts the string table building code into a separate class. The idea
is to use it for other object formats too.

I mostly wanted to do this for the general principle, but it does save a
little bit on object file size. I tried this on a clang bootstrap and
saved 0.54% on the sum of object file sizes (1.14 MB out of 212 MB for
a release build).

Differential Revision: http://reviews.llvm.org/D3533

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207670 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-30 16:25:02 +00:00
Benjamin Kramer
7259f14839 raw_ostream: Forward declare OpenFlags and include FileSystem.h only where necessary.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207593 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-29 23:26:49 +00:00
Simon Atanasyan
94a9772abc [yaml2obj][ELF] Remove unnecessary space between namespace name and
colons.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207003 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-23 17:30:29 +00:00
Simon Atanasyan
e8276ef418 [yaml2obj][ELF] Add a virtual destructor to the ELFYAML::Section class
to prevent memory leaks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206969 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-23 11:10:55 +00:00
Rafael Espindola
7426771280 Convert getFileOffset to getOffset and move it to its only user.
We normally don't drop functions from the C API's, but in this case I think we
can:

* The old implementation of getFileOffset was fairly broken
* The introduction of LLVMGetSymbolFileOffset was itself a C api breaking
  change as it removed LLVMGetSymbolOffset.
* It is an incredibly specialized use case. The only reason MCJIT needs it is
  because of its odd position of being a dynamic linker of .o files.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206750 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-21 13:45:32 +00:00
Craig Topper
0b6cb7104b [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206252 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-15 06:32:26 +00:00
Simon Atanasyan
eb0c9094ac [yaml2obj][ELF] ELF Relocations Support.
The patch implements support for both relocation record formats: Elf_Rel
and Elf_Rela. It is possible to define relocation against symbol only.
Relocations against sections will be implemented later. Now yaml2obj
recognizes X86_64, MIPS and Hexagon relocation types.

Example of relocation section specification:
Sections:
- Name: .text
  Type: SHT_PROGBITS
  Content: "0000000000000000"
  AddressAlign: 16
  Flags: [SHF_ALLOC]

- Name: .rel.text
  Type: SHT_REL
  Info: .text
  AddressAlign: 4
  Relocations:
    - Offset: 0x1
      Symbol: glob1
      Type: R_MIPS_32
    - Offset: 0x2
      Symbol: glob2
      Type: R_MIPS_CALL16

The patch reviewed by Michael Spencer, Sean Silva, Shankar Easwaran.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206017 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-11 04:13:39 +00:00
NAKAMURA Takumi
accaa640cf LLVMBuild.txt: Add missing dependencies.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205962 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-10 11:16:47 +00:00
NAKAMURA Takumi
6c5bb2e764 LLVMBuild.txt: Reformat.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205961 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-10 11:16:17 +00:00
David Majnemer
aef1966ed6 obj2yaml: Don't crash if the characteristics field is zero
obj2yaml would fail when seeing a Weak External auxiliary record with a
characteristics field holding zero instead of one of
IMAGE_WEAK_EXTERN_SEARCH_NOLIBRARY, IMAGE_WEAK_EXTERN_SEARCH_NOLIBRARY,
or IMAGE_WEAK_EXTERN_SEARCH_NOLIBRARY.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205911 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-09 16:38:15 +00:00
Saleem Abdulrasool
d640febcc8 Object: add type names for ARM/COFF relocations
Add type name mappings for the ARM COFF relocations.  This allows for objdump to
provide a more useful description of relocations in disassembly inline form.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205834 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-09 06:18:28 +00:00
David Majnemer
de6256c938 obj2yaml: Use the correct relocation type for different machine types
The IO normalizer would essentially lump I386 and AMD64 relocations
together.  Relocation types with the same numeric value would then get
mapped in appropriately.

For example:
IMAGE_REL_AMD64_ADDR64 and IMAGE_REL_I386_DIR16 both have a numeric
value of one.  We would see IMAGE_REL_I386_DIR16 in obj2yaml conversions
of object files with a machine type of IMAGE_FILE_MACHINE_AMD64.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205746 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-07 23:12:20 +00:00
Rafael Espindola
eec7d48f8e Add an assert that this is only used with .o files.
I am not sure how to get a relocation in a .dylib, but this function would
return the wrong value if passed one.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205592 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-04 00:31:12 +00:00
Rafael Espindola
7df9059541 Implement getRelocationAddress for MachO and ET_REL elf files.
With that, fix the symbolizer to work with any ELF file.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205588 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-03 23:54:35 +00:00
Rafael Espindola
5ca1f95419 Implement macho relocation iterators with section number + relocation number.
This will make it possible to implement getRelocationAddress.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205587 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-03 23:51:28 +00:00
Rafael Espindola
8cb805cf30 Fix llvm-objdump crash.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205581 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-03 23:20:02 +00:00
Rafael Espindola
67c46d286f Remove section_rel_empty. Just compare begin() and end() instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205577 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-03 22:42:22 +00:00
Rafael Espindola
051c948bbe Implement get getSymbolFileOffset with getSymbolAddress.
This has the following advantages:
* Less code.
* The old ELF implementation was wrong for non-relocatable objects.
* The old ELF implementation (and I think MachO) was wrong for thumb.

No current testcase since this is only used from MCJIT and it only uses
relocatable objects and I don't think it supports thumb yet.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205508 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-03 03:13:33 +00:00
Rafael Espindola
3539519223 Remove getSymbolValue.
All existing users explicitly ask for an address or a file offset.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205503 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-03 02:32:47 +00:00
Rafael Espindola
14ae43449c Revert "Fix a nomenclature error in llvm-nm."
This reverts commit r205479.

It turns out that nm does use addresses, it is just that every reasonable
relocatable ELF object has sections with address 0. I have no idea if those
exist in reality, but it at least it shows that llvm-nm should use the name
address.

The added test was includes an unusual .o file with non 0 section addresses. I
created it by hacking ELFObjectWriter.cpp.

Really sorry for the churn.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205493 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-03 00:19:35 +00:00
Rafael Espindola
5a61b72493 Fix a nomenclature error in llvm-nm.
What llvm-nm prints depends on the file format. On ELF for example, if the
file is relocatable, it prints offsets. If it is not, it prints addresses.
Since it doesn't really need to care what it is that it is printing, use the
generic term value.

Fix or implement getSymbolValue to keep llvm-nm working.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205479 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-02 22:52:46 +00:00
Daniel Sanders
002ba57eb7 [yaml2obj] Add support for ELF e_flags.
Summary:
The FileHeader mapping now accepts an optional Flags sequence that accepts
the EF_<arch>_<flag> constants. When not given, Flags defaults to zero.

Reviewers: atanasyan

Reviewed By: atanasyan

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D3213

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205173 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-31 09:44:05 +00:00
Tim Northover
7b837d8c75 ARM64: initial backend import
This adds a second implementation of the AArch64 architecture to LLVM,
accessible in parallel via the "arm64" triple. The plan over the
coming weeks & months is to merge the two into a single backend,
during which time thorough code review should naturally occur.

Everything will be easier with the target in-tree though, hence this
commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205090 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-29 10:18:08 +00:00
Juergen Ributzka
4923eea4f6 [RuntimeDyld] Allow processRelocationRef to process more than one relocation entry at a time.
Some targets require more than one relocation entry to perform a relocation.
This change allows processRelocationRef to process more than one relocation
entry at a time by passing the relocation iterator itself instead of just
the relocation entry.

Related to <rdar://problem/16199095>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204439 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-21 07:26:41 +00:00
Rui Ueyama
99995267ae Object/COFF: Support large relocation table.
NumberOfRelocations field in COFF section table is only 16-bit wide. If an
object has more than 65535 relocations, the number of relocations is stored
to VirtualAddress field in the first relocation field, and a special flag
(IMAGE_SCN_LNK_NRELOC_OVFL) is set to Characteristics field.

In test we cheated a bit. I made up a test file so that it has
IMAGE_SCN_LNK_NRELOC_OVFL flag but the number of relocations is much smaller
than 65535. This is to avoid checking in a large test file just to test a
file with many relocations.

Differential Revision: http://llvm-reviews.chandlerc.com/D3139

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204418 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-21 00:44:19 +00:00
David Majnemer
8bd2799a2d Object: Don't double-escape empty hexdata
We would emit a pair of double quotes inside a pair of single quotes.
Just use a pair of single quotes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204312 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-20 06:28:52 +00:00
David Majnemer
6d191534f6 Object: Provide a richer means of describing auxiliary symbols
The current state of affairs has auxiliary symbols described as a big
bag of bytes. This is less than satisfying, it detracts from the YAML
file as being human readable.

Instead, allow for symbols to optionally contain their auxiliary data.
This allows us to have a much higher level way of describing things like
weak symbols, function definitions and section definitions.

This depends on D3105.

Differential Revision: http://llvm-reviews.chandlerc.com/D3092

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204214 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-19 04:47:47 +00:00
Rui Ueyama
cae25dcbf7 Object/COFF: Add function to check if section number is reserved one.
Differential Revision: http://llvm-reviews.chandlerc.com/D3103

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204199 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-18 23:37:53 +00:00
Jim Grosbach
d55fc3f151 Darwin: Add assembler directives to create version-min load commands.
Allow object files to be tagged with a version-min load command for iOS
or MacOSX.

Teach macho-dump to understand the version-min load commands for
testcases.

rdar://11337778

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204190 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-18 22:09:05 +00:00
Alexey Samsonov
5b645797db [C++11] Change the interface of getCOFF{Section,Relocation,Symbol} to make it work with range-based for loops.
Reviewers: ruiu

Reviewed By: ruiu

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D3097

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204120 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-18 06:53:02 +00:00
Alexey Samsonov
133aacf0dd [C++11] Introduce ObjectFile::symbols() to use range-based loops.
Reviewers: rafael

Reviewed By: rafael

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D3081

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204031 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-17 07:28:19 +00:00
Justin Bogner
c0a42c263e Support: Make error_category's constructor public
Since our error_category is based on the std one, we should have the
same visibility for the constructor.  This also allows us to avoid
using the _do_message implementation detail in our own categories.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203998 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-15 04:05:59 +00:00
Rafael Espindola
1f21e0dd0d Remove the linker_private and linker_private_weak linkages.
These linkages were introduced some time ago, but it was never very
clear what exactly their semantics were or what they should be used
for. Some investigation found these uses:

* utf-16 strings in clang.
* non-unnamed_addr strings produced by the sanitizers.

It turns out they were just working around a more fundamental problem.
For some sections a MachO linker needs a symbol in order to split the
section into atoms, and llvm had no idea that was the case. I fixed
that in r201700 and it is now safe to use the private linkage. When
the object ends up in a section that requires symbols, llvm will use a
'l' prefix instead of a 'L' prefix and things just work.

With that, these linkages were already dead, but there was a potential
future user in the objc metadata information. I am still looking at
CGObjcMac.cpp, but at this point I am convinced that linker_private
and linker_private_weak are not what they need.

The objc uses are currently split in

* Regular symbols (no '\01' prefix). LLVM already directly provides
whatever semantics they need.
* Uses of a private name (start with "\01L" or "\01l") and private
linkage. We can drop the "\01L" and "\01l" prefixes as soon as llvm
agrees with clang on L being ok or not for a given section. I have two
patches in code review for this.
* Uses of private name and weak linkage.

The last case is the one that one could think would fit one of these
linkages. That is not the case. The semantics are

* the linker will merge these symbol by *name*.
* the linker will hide them in the final DSO.

Given that the merging is done by name, any of the private (or
internal) linkages would be a bad match. They allow llvm to rename the
symbols, and that is really not what we want. From the llvm point of
view, these objects should really be (linkonce|weak)(_odr)?.

For now, just keeping the "\01l" prefix is probably the best for these
symbols. If we one day want to have a more direct support in llvm,
IMHO what we should add is not a linkage, it is just a hidden_symbol
attribute. It would be applicable to multiple linkages. For example,
on weak it would produce the current behavior we have for objc
metadata. On internal, it would be equivalent to private (and we
should then remove private).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203866 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-13 23:18:37 +00:00
Alexey Samsonov
b920dfe02b [C++11] Introduce ObjectFile::sections().
Summary:
This adds ObjectFile::section_iterator_range, that allows to write
range-based for-loops running over all sections of a given file.
Several files from lib/ are converted to the new interface. Similar fixes
should be applied to a variety of llvm-* tools.

Reviewers: rafael

Reviewed By: rafael

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D3069

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203799 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-13 13:52:54 +00:00