Commit Graph

352 Commits

Author SHA1 Message Date
Rafael Espindola 1998ee53f0 Simplify. NFC.
With the recent changes there should always be a 1:1 correspondence in
the correct order between OutputSections and OutputSectionCommands.

llvm-svn: 282176
2016-09-22 17:23:53 +00:00
Rafael Espindola 0d4b6d5c98 Avoid duplicated code.
This also fixes the linker script accounting for the ELF header in
some places but not in others.

llvm-svn: 282173
2016-09-22 16:47:21 +00:00
Rafael Espindola 2644208381 Simplify. NFC.
It doesn't matter which direction we rotate and we haven't really
started optimizing the linker script code, so keep this simple.

llvm-svn: 282166
2016-09-22 15:25:21 +00:00
Rafael Espindola 9546fffbfe Handle empty sections with symbol assignments.
Before the symbols were becoming undefined.

llvm-svn: 282159
2016-09-22 14:40:50 +00:00
Rafael Espindola a940e5396b Fix VA computation for tbss.
llvm-svn: 282149
2016-09-22 12:35:44 +00:00
Rafael Espindola 7252ae52cf Handle multiple .tbss sections.
llvm-svn: 282147
2016-09-22 12:00:08 +00:00
Rafael Espindola e746e52c7b Implement ONLY_IF_RO/ONLY_IF_RW like bfd.
The actual logic is to keep the output section if the output section
would have been ro/rw.

This is both simpler and more practical, as the intention is linker
scripts is to always keep of of a pair of ONLY_IF_RO/ONLY_IF_RW.

llvm-svn: 282099
2016-09-21 18:33:44 +00:00
George Rimar 07171f21d1 [ELF] - Linkerscript: support complex section pattern grammar.
This is PR30442.
Previously we were failed to parce complex expressions like:
foo : { *(SORT_BY_NAME(bar) zed) }

Main idea of patch that globs and excludes can be wrapped in a SORT.
There is a difference in semanics of ld/gold:
ld likes:
*(SORT(EXCLUDE_FILE (*file1.o) .foo.1))

gold likes:
*(EXCLUDE_FILE (*file1.o) SORT(.foo.1))

Patch implements ld grammar, complex expressions like 
next is not a problem anymore:
.abc : { *(SORT(.foo.* EXCLUDE_FILE (*file1.o) .bar.*) .bar.*) }


Differential revision: https://reviews.llvm.org/D24758

llvm-svn: 282078
2016-09-21 15:56:44 +00:00
Eugene Leviant 2506cb4ddb Linker script: Fix bug with several .bss
When final image has several .bss sections, lld fails
because second .bss always has zero VA. This causes 
link error "Not enough space for ELF and program headers"

llvm-svn: 282067
2016-09-21 11:29:28 +00:00
George Rimar 601e989879 [ELF] - Linkerscript: reimplement readSectionExcludes()
It is not only a bit more straightforward now, but also next 2 issues are solved:

* It just crashed on ".foo : { *(EXCLUDE_FILE (*file1.o)) }" before.
* It accepted multiple EXCLUDE_FILEs in a row.

Differential revision: https://reviews.llvm.org/D24726

llvm-svn: 282060
2016-09-21 08:53:21 +00:00
Rafael Espindola b6b8f6c308 Revert "Revert "Only restrict order if both sections are in the script.""
This reverts commit r282021, bringing back r282015.

The problem was that the comparison function was not a strict weak
ordering anymore, which this patch fixes.

Original message:

Only restrict order if both sections are in the script.

This matches gold and bfd behavior and is required to handle some scripts.

The script has to assume where PT_LOADs start in order to align that
spot. If we don't allow section it doesn't know about to move to the
middle, we can need more PT_LOADs and those will not be aligned.

llvm-svn: 282035
2016-09-20 22:43:15 +00:00
Rafael Espindola bf04708e11 Revert "Only restrict order if both sections are in the script."
This reverts commit r282015. It broke some bots.

llvm-svn: 282021
2016-09-20 21:28:19 +00:00
Rafael Espindola 145569df64 Only restrict order if both sections are in the script.
This matches gold and bfd behavior and is required to handle some scripts.

The script has to assume where PT_LOADs start in order to align that
spot. If we don't allow section it doesn't know about to move to the
middle, we can need more PT_LOADs and those will not be aligned.

llvm-svn: 282015
2016-09-20 20:54:39 +00:00
Rui Ueyama ee92470969 Simplify SORT and --sort-section command line option handling.
Differential Revision: https://reviews.llvm.org/D24685

llvm-svn: 282006
2016-09-20 19:42:41 +00:00
Rafael Espindola 6d38e4dbe1 Remove empty section commands.
We were already not creating them, and with this other parts of the
code don't have to worry about them.

llvm-svn: 281968
2016-09-20 13:12:07 +00:00
Rafael Espindola f135f0ec1d Remove unnecessary const_canst. NFC.
llvm-svn: 281901
2016-09-19 13:33:38 +00:00
George Rimar b31dd37005 [ELF] - LinkerScript: Add workaround for gcc 6.2.0 failure w/auto
Will Dietz found and reported that lld does not compile with gcc 6.2.0,
more details https://llvm.org/bugs/show_bug.cgi?id=30438

And confirmed this change fixes the issue.

llvm-svn: 281900
2016-09-19 13:27:31 +00:00
George Rimar 194470cd11 [ELF] - Fix comment. NFC.
llvm-svn: 281836
2016-09-17 19:21:05 +00:00
George Rimar af03be19f9 [ELF] - Added comments. NFC.
llvm-svn: 281835
2016-09-17 19:17:25 +00:00
George Rimar 8c658bf824 [ELF] - SEGMENT_START's default argument can be an expression
Our implementation supported integer value previously.
ld can use expression,
for example, it is OK to write
 . = SEGMENT_START("foobar", .);

Patch implements that.

llvm-svn: 281831
2016-09-17 18:14:56 +00:00
George Rimar dfbbbc86a1 [ELF] Linkerscript: fixed bug about commands processing.
It was possible situation about some commands just were not processed
(were skipped) because of a bug appeared when constraint checking used.

Testcase is attached.

llvm-svn: 281818
2016-09-17 09:50:10 +00:00
Rui Ueyama 4dc07becd0 Use named struct instead of unnamed std::pair.
It is important to give members names for readability.

llvm-svn: 281803
2016-09-17 02:23:40 +00:00
Rui Ueyama 3ff27f49cd Define a versatile utility function and use it instead of a single purpose one.
llvm-svn: 281802
2016-09-17 02:15:28 +00:00
Rui Ueyama 027a9e8787 Remove unnecessary namespace specifiers.
llvm-svn: 281801
2016-09-17 02:10:15 +00:00
Rafael Espindola 373343bd5b Try to fix a few bots.
llvm-svn: 281794
2016-09-16 22:47:34 +00:00
Rafael Espindola aab6d5c52a Put SHF_ALLOC sections first, even with linker scripts.
This matches gold and bfd, and is pretty much required by some linker
scripts. They end with commands like

foo   0 : { *(bar) }

if we put any SHF_ALLOC sections after they can have an address that
is too low.

llvm-svn: 281778
2016-09-16 21:29:07 +00:00
Rui Ueyama b2a0abdf0e Rename SortSectionPolicy::IgnoreConfig to None.
Because it corresponds to SORT_NONE. None was renamed Default.

llvm-svn: 281776
2016-09-16 21:14:55 +00:00
Rafael Espindola 7c3ff2eb58 Only process commands in a ONLY_IF_RO if it matches.
This matches bfd behavior. It also makes future changes simpler as we
don't have to worry about ignoring these commands in multiple places

llvm-svn: 281775
2016-09-16 21:05:36 +00:00
Rafael Espindola e71a3f8ae1 Fix constraint checking in ONLY_IF_RO.
We have to look at all the relevant input sections at once.

llvm-svn: 281772
2016-09-16 20:34:02 +00:00
George Rimar be394db376 [ELF] - Implemented --sort-section cmd line option and SORT_NONE script command.
This fixes Bug 30385 - SORT_NONE not implemented,

`SORT_NONE' disables section sorting by ignoring the command line
section sorting option.

That is why this patch also implements --sort-section option.

Description of sorting rules
available at https://sourceware.org/binutils/docs/ld/Input-Section-Wildcards.html 

Differential revision: https://reviews.llvm.org/D24604

llvm-svn: 281771
2016-09-16 20:21:55 +00:00
George Rimar 395281cfc3 Recommit r281721 "[ELF] - Linkerscript: implement EXCLUDE_FILE in the middle of a input section description."
With fix for 2 bots. Details about the fix performed is on a review page.

Initial commit message:
This is PR30387:

From PR description:
We fail to parse

SECTIONS
{
  foo :
  {
    *(sec0 EXCLUDE_FILE (zed1.o) sec1  EXCLUDE_FILE (zed2.o) sec2 )
  }
}
The semantics according to bfd are:

Include sec1 from every file but zed1.o
Include sec2 from every file but zed2.o
Include sec0 from every file

Patch implements the support.

Differential revision: https://reviews.llvm.org/D24650

llvm-svn: 281754
2016-09-16 17:42:10 +00:00
Eugene Leviant 20d031948e Improve handling ASSERT outside SECTIONS block
Differential revision: https://reviews.llvm.org/D24450

llvm-svn: 281740
2016-09-16 15:30:47 +00:00
Rafael Espindola d31907957a Change how we compute offsets with linker scripts.
This fixes pr30367, but more importantly, it changes how we compute offsets.

Now offset computation in a walk over linker script commands, like the
rest of assignAddresses. IMHO this is simpler to understand and if we
ever have to create multiple outputsections or chunks to change how we
handle test/ELF/linkerscript/alternate-sections.s it should be easier
to do it.

llvm-svn: 281736
2016-09-16 15:10:23 +00:00
George Rimar ceae630c9b Reverted r281721 ("[ELF] - Linkerscript: implement EXCLUDE_FILE in the middle of a input section description.").
It broke build bot:
http://lab.llvm.org:8011/builders/lld-x86_64-darwin13/builds/27508

llvm-svn: 281723
2016-09-16 13:30:18 +00:00
George Rimar 4906c7f5c4 [ELF] - Linkerscript: implement EXCLUDE_FILE in the middle of a input section description.
This is PR30387:

From PR description:
We fail to parse

SECTIONS
{
  foo :
  {
    *(sec0 EXCLUDE_FILE (zed1.o) sec1  EXCLUDE_FILE (zed2.o) sec2 )
  }
}
The semantics according to bfd are:

Include sec1 from every file but zed1.o
Include sec2 from every file but zed2.o
Include sec0 from every file

Patch implements the support.

Differential revision: https://reviews.llvm.org/D24650

llvm-svn: 281721
2016-09-16 13:07:02 +00:00
Rafael Espindola 4ec013ac83 Error out instead of producing a corrupt PT_LOAD.
What bfd and gold do is give up in putting the headers in the PT_LOAD
and just start the PT_LOAD in the second page.

llvm-svn: 281660
2016-09-15 21:22:11 +00:00
George Rimar 575208cabd [ELF] - Linkerscript: implemented SORT_BY_INIT_PRIORITY.
This is PR30386,

SORT_BY_INIT_PRIORITY is a keyword can be used to sort sections by numerical value of the
GCC init_priority attribute encoded in the section name.

Differential revision: https://reviews.llvm.org/D24611

llvm-svn: 281646
2016-09-15 19:15:12 +00:00
Rafael Espindola 3adbbc3891 Check the return of getInteger.
llvm-svn: 281608
2016-09-15 13:36:44 +00:00
Rafael Espindola 97bdc7220b Handle arbitrary expressions in DATA_SEGMENT_RELRO_END.
llvm-svn: 281521
2016-09-14 19:14:01 +00:00
Rafael Espindola be94e1b630 Move helper function higher in the file. NFC
This just makes a followup patch easier to read.

llvm-svn: 281482
2016-09-14 14:32:08 +00:00
Eugene Leviant e05336ffa1 [ELF] Replace HasContents with HasSections. NFC
llvm-svn: 281449
2016-09-14 08:32:36 +00:00
Rui Ueyama 38dbd3eea9 Simplify InputFile ownership management.
Previously, all input files were owned by the symbol table.
Files were created at various places, such as the Driver, the lazy
symbols, or the bitcode compiler, and the ownership of new files
was transferred to the symbol table using std::unique_ptr.
All input files were then free'd when the symbol table is freed
which is on program exit.

I think we don't have to transfer ownership just to free all
instance at once on exit.

In this patch, all instances are automatically collected to a
vector and freed on exit. In this way, we no longer have to
use std::unique_ptr.

Differential Revision: https://reviews.llvm.org/D24493

llvm-svn: 281425
2016-09-14 00:05:51 +00:00
Rafael Espindola 10897f1807 Enable merging of SHF_MERGE sections with linker scripts.
This also fixes the related problem of non SHF_MERGE sections with
different flags not being merged.

Fixes pr30355.

llvm-svn: 281338
2016-09-13 14:23:14 +00:00
Rafael Espindola 28c1597ad9 Refactor duplicated code. NFC.
llvm-svn: 281329
2016-09-13 13:00:06 +00:00
Rafael Espindola 540893a2e2 Delete dead code.
We already handle this is createSections.

llvm-svn: 281320
2016-09-13 11:28:22 +00:00
Rafael Espindola 7bd37870bc Simplify handling of /DISCARD/. NFC.
llvm-svn: 281222
2016-09-12 16:05:16 +00:00
George Rimar cd574a5e46 Recommit [ELF] - Versionscript: do not treat non-wildcarded names as wildcards.
Fixed code that was not checked before on windows for me, because of testcases that are
disabled on that platform atm.

Inital commit message:
"[ELF] - Versionscript: do not treat non-wildcarded names as wildcards."
Previously we incorrectly handled cases when symbol name in extern c++ tag
was enclosed in quotes. Next case was treated as wildcard:

GLIBCXX_3.4 {                                                                   
    extern "C++" {  
    "aaa*"
   }
But it should have not. Quotes around aaa here means that we should have do exact
name matching.
That is PR30268 which has name with pointer is interpreted as wildcard by lld:

extern "C++" {                                                              
    "operator delete[](void*)";

Patch fixes the issue.

Differential revision: https://reviews.llvm.org/D24229

llvm-svn: 281049
2016-09-09 14:35:36 +00:00
George Rimar 6368525eea Revert r281045, it broke BB.
Broken BB:
http://lab.llvm.org:8011/builders/lld-x86_64-darwin13/builds/27211

llvm-svn: 281046
2016-09-09 14:16:00 +00:00
George Rimar b5e77c47fb Recommit [ELF] - Versionscript: do not treat non-wildcarded names as wildcards.
Fixed code that was not checked by testcases that are disabled on windows.

Inital commit message:
"[ELF] - Versionscript: do not treat non-wildcarded names as wildcards."
Previously we incorrectly handled cases when symbol name in extern c++ tag
was enclosed in quotes. Next case was treated as wildcard:

GLIBCXX_3.4 {                                                                   
    extern "C++" {  
    "aaa*"
   }
But it should have not. Quotes around aaa here means that we should have do exact
name matching.
That is PR30268 which has name with pointer is interpreted as wildcard by lld:

extern "C++" {                                                              
    "operator delete[](void*)";

Patch fixes the issue.

Differential revision: https://reviews.llvm.org/D24229

llvm-svn: 281045
2016-09-09 13:58:07 +00:00
George Rimar 08b1862caf [ELF] - Revert r281038 to see if that unbreaks build bot.
http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast/builds/19703

llvm-svn: 281041
2016-09-09 12:56:55 +00:00
George Rimar d220384376 [ELF] - Versionscript: do not treat non-wildcarded names as wildcards.
Previously we incorrectly handled cases when symbol name in extern c++ tag
was enclosed in quotes. Next case was treated as wildcard:

GLIBCXX_3.4 {                                                                   
    extern "C++" {  
    "aaa*"
   }
But it should have not. Quotes around aaa here means that we should have do exact
name matching.
That is PR30268 which has name with pointer is interpreted as wildcard by lld:

extern "C++" {                                                              
    "operator delete[](void*)";

Patch fixes the issue.

Differential revision: https://reviews.llvm.org/D24229

llvm-svn: 281038
2016-09-09 12:22:28 +00:00
Eugene Leviant 56b21c869e Linker script: implement AT [ (address) ] for PHDR
Differential revision: https://reviews.llvm.org/D24340

llvm-svn: 281024
2016-09-09 09:46:16 +00:00
Rui Ueyama 86c5fb8296 Fix bug in -nostdlib.
We still have to skip a token inside SEARCH_DIR() when -nostdlib is
specified. Previuosly, we didn't skip it, so it caused a parse error.

llvm-svn: 281001
2016-09-08 23:26:54 +00:00
Rafael Espindola c0028d3d3b Reduce templating. NFC.
llvm-svn: 280986
2016-09-08 20:47:52 +00:00
Rafael Espindola 042a3f209b Compute section names only once.
This simplifies error handling as there is now only one place in the
code that needs to consider the possibility that the name is
corrupted. Before we would do it in every access.

llvm-svn: 280937
2016-09-08 14:06:08 +00:00
Eugene Leviant 36fac7f0d0 Linker script: implement ALIGNOF
Differential revision: https://reviews.llvm.org/D24141

llvm-svn: 280915
2016-09-08 09:08:30 +00:00
George Rimar 6c55f0e35e [ELF] - Apply clang-format to LinkerScript.cpp, NFC.
llvm-svn: 280911
2016-09-08 08:20:30 +00:00
George Rimar 884e786d38 [ELF] - Linkerscript: simplify access to templated methods from parser.
Previous way of accessing templated methods was a bit bulky,
Patch introduces small interface based solution.

Differential revision: https://reviews.llvm.org/D23872

llvm-svn: 280910
2016-09-08 08:19:13 +00:00
George Rimar a14b13d867 [ELF] - Linkerscript: create multiple output sections for inputs with different attributes.
Previously we combined sections by name if linkerscript was used.
For that we had to disable SHF_MERGE handling temporarily, but then
found that implementing it properly will require additional complexity layers like
subsections or something.
At the same time looks we can live with multiple output sections approach for now.
That patch do this change.

Differential revision: https://reviews.llvm.org/D24127

llvm-svn: 280801
2016-09-07 10:46:07 +00:00
Eugene Leviant db741e7203 Support ABSOLUE keyword in symbol assignments
This patch allows making section defined symbols absolute:
.foo : {
  begin_foo = ABSOLUTE(.);
  *(.foo)
}

Differential revision: https://reviews.llvm.org/D24135

llvm-svn: 280788
2016-09-07 07:08:43 +00:00
Rui Ueyama adcdb664cb Simplify a boolean expression by using the De Morgan's law.
llvm-svn: 280766
2016-09-06 22:50:48 +00:00
Rui Ueyama 25150e8b0d Add a comment.
llvm-svn: 280724
2016-09-06 17:46:43 +00:00
George Rimar ff1f29e0f6 [ELF] - Linkerscript: implemented FILL command as alias for =fillexpr
Patch implements FILL just as alias for =fillexpr. 
This allows to make implementation much shorted and simpler than D24186.

Differential revision: https://reviews.llvm.org/D24227

llvm-svn: 280708
2016-09-06 13:51:57 +00:00
Simon Atanasyan eaeafb2b4f [ELF] PR30221 - linker script expression parser does not accept '~'
The patch adds support for both '-' and '~' unary expressions. Also it
brings support for signed numbers is expressions.

https://llvm.org/bugs/show_bug.cgi?id=30221

Differential revision: https://reviews.llvm.org/D24128

llvm-svn: 280546
2016-09-02 21:54:35 +00:00
George Rimar c91930a17f [ELF] - Use std::regex instead of hand written logic in elf::globMatch()
Use std::regex instead of hand written matcher.

Patch based on code and ideas of Rui Ueyama.

Differential revision: https://reviews.llvm.org/D23829

llvm-svn: 280544
2016-09-02 21:17:20 +00:00
Rui Ueyama 6c7ad13f89 Add -nostdlib.
llvm-svn: 280528
2016-09-02 19:20:33 +00:00
Rui Ueyama a27eeccade Dispatch without hash table lookup.
Cmd used to be the single central place to dispatch. It is not longer
the case because we have a logic for readProvideOrAssignment().
This patch removes the hash table so that evrything is in a single
function. This is slightly verbose but should improve readability.

Differential Revision: https://reviews.llvm.org/D24200

llvm-svn: 280524
2016-09-02 18:52:41 +00:00
Rui Ueyama 626e0b08ac Add comments.
llvm-svn: 280515
2016-09-02 18:19:00 +00:00
George Rimar 9f2f7ad98b [ELF] - Linkerscript: add support for suffixes in numbers.
Both bfd and gold accept:
foo = 1K;
bar = 1M;
zed = 1H;

And lowercase forms: k, m, h.
Patch adds support for that.

Differential revision: https://reviews.llvm.org/D24194

llvm-svn: 280494
2016-09-02 16:01:42 +00:00
Eugene Leviant 97403d15ee Eliminate LayoutInputSection class
Previously we used LayoutInputSection class to correctly assign
symbols defined in linker script. This patch removes it and uses
pointer to preceding input section in SymbolAssignment class instead.

Differential revision: https://reviews.llvm.org/D23661

llvm-svn: 280348
2016-09-01 09:55:57 +00:00
Rui Ueyama 95769b4a29 Linker script: support VERSION command.
Summary:
VERSION commands define symbol versions. The grammar of the
commnad is as follows

  VERSION { version-script-commands }

where version-script-commands is

  [ name ] { version-definitions }.

Note that we already support version-script-commands because
it is being used for version script command.

This patch is based on George's patch https://reviews.llvm.org/D23609

Reviewers: grimar

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D24089

llvm-svn: 280284
2016-08-31 20:03:54 +00:00
Petr Hosek e5d3ca5031 [ELF] Linkerscript: define symbols outside SECTIONS
Symbol assignments outside of SECTIONS command need to be created
even when SECTIONS command is not used.

Differential Revision: https://reviews.llvm.org/D23751

llvm-svn: 280252
2016-08-31 15:31:17 +00:00
George Rimar 20b6598c10 [ELF] - Remove VersionScriptParser class and move the members to ScriptParser
Patch removes VersionScriptParser class and moves the members to ScriptParser
It opens road for implementation of VERSION linkerscript command.

Differential revision: https://reviews.llvm.org/D23774

llvm-svn: 280212
2016-08-31 09:08:26 +00:00
Eugene Leviant 20889c51b7 Allow adding start/end symbols to any section
Allows adding start and/or end symbols to special output sections,
like .eh_frame_hdr, which aren't lists of regular input sections. 

Differential revision: https://reviews.llvm.org/D23716

llvm-svn: 280205
2016-08-31 08:13:33 +00:00
George Rimar 96659df09c [ELF] - Linkerscript: implemented ADDR command.
ADDR(section)
Return the absolute address (the VMA) of the named section.

Used in the wild, eg.: https://searchcode.com/file/53617342/arch/x86/kernel/vmlinux.lds.S

Differential revision: https://reviews.llvm.org/D23913

llvm-svn: 280070
2016-08-30 09:54:01 +00:00
George Rimar a2496cbed4 [ELF] - Fix for: bug 29115 - linkerscript does not support non-wildcard filename spec.
FreeBSD/mips script has non-wildcard filename specifications:
.text :
{
 start.o(.text*)

Patch adds support for that, this is PR29115.

Differential revision: https://reviews.llvm.org/D23839

llvm-svn: 280069
2016-08-30 09:46:59 +00:00
Rui Ueyama 2c8f1f048c Make lld actually compatible with gold in terms of filler handling.
GNU gold handles output section fillers as 32-bit values.
This patch makes LLD compatible with that behavior.

Differential revision: https://reviews.llvm.org/D23181

llvm-svn: 280018
2016-08-29 22:01:21 +00:00
Rafael Espindola cc3dd629ee Add support for '|' in expressions.
llvm-svn: 279480
2016-08-22 21:33:35 +00:00
Rui Ueyama 464daadc3d Do not add .interp, .dynamic nor .eh_frame_hdr to segments just by type.
Summary:
We previously added these output sections to segments just by type.
Therefore, if there's a PHDRS command like this

  PHDRS {
    headers PT_PHDR PHDRS;
    interp PT_INTERP;
  }

  SECTIONS {
    . = SIZEOF_HEADERS;
    .interp : { *(.interp) } :text
  }

then .interp was added to "interp" segment even though the linker
is not instructed to do so by SECTIONS command. This patch removes
the default behavior to simplify.

Differential Revision: https://reviews.llvm.org/D23702

llvm-svn: 279414
2016-08-22 04:55:20 +00:00
George Rimar e1937bb524 [ELF] - Give automatically generated __start_* and __stop_* symbols default visibility.
This patch is opposite to D19024, which made this symbols to be hidden by default.

Unfortunately FreeBSD loader wants to see
start_set_modmetadata_set/stop_set_modmetadata_set in the dynamic symbol table. 
They were not placed there because had hidden visibility.

Patch makes them to have default visibility again.

Differential revision: https://reviews.llvm.org/D23552

llvm-svn: 279262
2016-08-19 15:36:32 +00:00
George Rimar db24d9c3e8 [ELF] - Linkerscript: implemented SUBALIGN() command.
You can force input section alignment within an output section by using SUBALIGN. The
value specified overrides any alignment given by input sections, whether larger or smaller.

SUBALIGN is used in many projects in the wild.

Differential revision: https://reviews.llvm.org/D23063

llvm-svn: 279256
2016-08-19 15:18:23 +00:00
Eugene Leviant 3f675e38bd [ELF] Don't add input sections twice when linker script is used
llvm-svn: 279036
2016-08-18 07:27:37 +00:00
Petr Hosek 0df80bef96 [ELF] Linkerscript: support assignment outside SECTIONS
We only support assignments inside SECTIONS, but this does not match
the behavior of GNU linker which also allows them outside SECTIONS.
The only restriction on assignments outside SECTIONS is that they
cannot reference . (they have to be absolute expressions).

Differential Revision: https://reviews.llvm.org/D23598

llvm-svn: 279033
2016-08-18 04:34:27 +00:00
Rui Ueyama 6ad7dfcc1e Merge readAt and readAlign.
Now that they are identical.

llvm-svn: 278953
2016-08-17 18:59:16 +00:00
George Rimar 545afafb70 [ELF] - Linkerscript: make readAt() signature to be consistent with others read*(). NFC.
llvm-svn: 278931
2016-08-17 14:48:17 +00:00
George Rimar 206fffa192 Attemp to fix linux build bot after r278911 ("[ELF] - linkerscript AT keyword (in output section description) implemented.")
http://lab.llvm.org:8011/builders/lld-x86_64-darwin13/builds/26289/steps/build_Lld/logs/stdio

llvm-svn: 278914
2016-08-17 08:16:57 +00:00
George Rimar 8ceadb38a8 [ELF] - linkerscript AT keyword (in output section description) implemented.
The linker will normally set the LMA equal to the VMA. 
You can change that by using the AT keyword.
The expression lma that follows the AT keyword specifies 
the load address of the section.

Patch implements this keyword.

Differential revision: https://reviews.llvm.org/D19272

llvm-svn: 278911
2016-08-17 07:44:19 +00:00
Michael J. Spencer e2cc07bc0b [ELF] Set MAXPAGESIZE to 2MiB on x86-64 to match bfd and gold.
The FreeBSD kernel relies on this behavior to not overwrite the boot loader.

llvm-svn: 278889
2016-08-17 02:10:51 +00:00
Eugene Leviant f9bc3bd2cf [ELF] Ignore .interp section in case linker script specifies PHDRS without PT_INTERP
llvm-svn: 278781
2016-08-16 06:40:58 +00:00
Petr Hosek a35e39ca2e [ELF] Linkerscript: support hidden symbols assignments
This add support for HIDDEN command which can be used to define
a symbol that will be hidden and won't be exported.

Differential Revision: https://reviews.llvm.org/D23534

llvm-svn: 278770
2016-08-16 01:11:16 +00:00
Eugene Leviant b6f1bb13ae [ELF] Linkerscript: fix bug in assignOffsets (check Sym for non-null)
llvm-svn: 278663
2016-08-15 09:19:51 +00:00
George Rimar 8f66df92ba [ELF] - Linkerscript: fix VA value assigned to sections when using constraints.
Previously we searched output section by name to assign VA. That did not
work in the case when multiple output sections with different constraints were defined in script.
Testcase shows the possible issue scenario, patch fixes the issue.

Differential revision: https://reviews.llvm.org/D23451

llvm-svn: 278561
2016-08-12 20:38:20 +00:00
George Rimar b6c52e8dfa [ELF] - Remove excessive loop in LinkerScript<ELFT>::assignAddresses()
After 278461 "Create only one section for a name in LinkerScript."
this loop is excessive. 
Patch also reorders code slightly to use early return.

Differential revision: https://reviews.llvm.org/D23442

llvm-svn: 278554
2016-08-12 19:32:45 +00:00
George Rimar 06ae683620 [ELF] - Linkerscript: reimplemented output sections constrains matching functionality.
Previously filtering that was used worked incorrectly. 
For example for next script it would just remove both sections completely:

SECTIONS { 
. = 0x1000;
.aaa : ONLY_IF_RW { *(.aaa.*) } 
. = 0x2000;
.aaa : ONLY_IF_RO { *(.aaa.*) } 
}

Patch fixes above issues and adds testcase showing the issue. Testcase is a subset of
FreeBSD script which has:

.eh_frame       : ONLY_IF_RO { KEEP (*(.eh_frame)) }
...
.eh_frame       : ONLY_IF_RW { KEEP (*(.eh_frame)) }

Differential revision: https://reviews.llvm.org/D23326

llvm-svn: 278486
2016-08-12 09:07:57 +00:00
Rui Ueyama 4f7500bfc2 Rename getSizeOfHeaders -> getHeaderSize.
We have getSectionSize for SIZEOF command. So, I think
getHeaderSize is a better name for SIZEOF_HEADERS.

llvm-svn: 278470
2016-08-12 04:00:22 +00:00
Rui Ueyama 2ab5f73d5a Early continue. NFC.
llvm-svn: 278465
2016-08-12 03:33:04 +00:00
Rui Ueyama 0c70d3ccb7 Simplify LinkerScript<ELFT>::createSections.
Previously, we were setting LayoutInputSection's OutputSection member
in createSections. Because when we create LayoutInputSectinos, we
don't know the output section for them, so we backfilled the member
in the function. This patch moves the code to backfill it to assignOffsets.

llvm-svn: 278464
2016-08-12 03:31:09 +00:00
Rui Ueyama 7ad9d6d2f0 Remove excessive parentheses.
llvm-svn: 278462
2016-08-12 03:25:25 +00:00
Rui Ueyama 0b9ce6a48a Create only one section for a name in LinkerScript.
Previously, we created two or more output sections if there are
input sections with the same name but with different attributes.
That is a wrong behavior. This patch fixes the issue.

One thing we need to do is to merge output section attributes.
Currently, we create an output section based on the first input
section's attributes. This may make a wrong output section
attributes. What we need to do is to bitwise-OR attributes.
We'll do it in a follow-up patch.

llvm-svn: 278461
2016-08-12 03:16:56 +00:00
Rui Ueyama f34d0e0875 Allocate LayoutInputSections using SpecificBumpPtrAllocator.
llvm-svn: 278453
2016-08-12 01:24:53 +00:00