Commit Graph

312 Commits

Author SHA1 Message Date
Petr Hosek 997f8838e5 [ELF] Support -z max-page-size option
This options issupported by both BFD ld and gold and allows
overriding the max page size whose default values are defined by
the target.

https://llvm.org/bugs/show_bug.cgi?id=30541

Differential Revision: https://reviews.llvm.org/D24891

llvm-svn: 282596
2016-09-28 15:20:47 +00:00
George Rimar e38cbab5a4 [ELF] - Linkerscript: implemented BYTE/SHORT/LONG/QUAD commands.
The BYTE, SHORT, LONG, and QUAD commands store one, two, four, and eight bytes (respectively). 
After storing the bytes, the location counter is incremented by the number of bytes
stored.

Previously our scripts handles these commands incorrectly. For example:
SECTIONS  {
  .foo : {
 *(.foo.1)
 BYTE(0x11)
...
We accepted the script above treating BYTE as input section description. 
These commands are used in the wild though.

Differential revision: https://reviews.llvm.org/D24830

llvm-svn: 282429
2016-09-26 19:22:50 +00:00
George Rimar f28210285b [ELF] - Format. NFC.
llvm-svn: 282395
2016-09-26 11:00:48 +00:00
Rui Ueyama 9c4ac5f26c Combine two StringSwitch::Cases because Cases now can take 6 parameters.
llvm-svn: 282307
2016-09-23 22:22:34 +00:00
Rafael Espindola 65499b9040 Avoid counting sections twice.
We were counting the size of the bss section holding common symbols twice:

    Dot += CurOutSec->getSize();
    flush();

The new code is also simpler as now flush is the only function that
inserts in AlreadyOutputOS, which makes sense since the set hold fully
output sections.

llvm-svn: 282285
2016-09-23 20:10:47 +00:00
Rui Ueyama 0120e3f278 Simplify. NFC.
llvm-svn: 282268
2016-09-23 18:06:51 +00:00
George Rimar 4ebc562052 [ELF] - Linkerscript: accept space between '=' and expression in section filler.
Previously we failed to parse next scripts because disallowed
a space between filler value and '=':

  .text : {
...
  } :text = 0x9090

Differential revision: https://reviews.llvm.org/D24831

llvm-svn: 282248
2016-09-23 13:29:20 +00:00
George Rimar f34f45fd53 [ELF] - Linkerscript: implement DEFINED() command.
DEFINED(symbol)
Return 1 if symbol is in the linker global symbol table and is defined before
the statement using DEFINED in the script, otherwise return 0.

Can be used to define default values for symbols. Found it in the wild.

Differential revision: https://reviews.llvm.org/D24858

llvm-svn: 282245
2016-09-23 13:17:23 +00:00
George Rimar c8ccd1f1c5 [ELF] - Linkerscript: Implemented >> and <<
Found this operators used in the wild scripts, for example:

__got2_entries = (_FIXUP_TABLE_ - _GOT2_TABLE_) >>2;
__fixup_entries = (. - _FIXUP_TABLE_)>>2;

Differential revision: https://reviews.llvm.org/D24860

llvm-svn: 282243
2016-09-23 13:13:55 +00:00
Rafael Espindola 15c579518d Don't move orphan sections past assignments.
This fixes a case where we would produce an unaligned PT_LOAD.

llvm-svn: 282180
2016-09-22 18:05:49 +00:00
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