Commit Graph

417 Commits

Author SHA1 Message Date
Meador Inge 8f1f3c40f6 [ELF] Allow defined symbols to be assigned from linker script
This patch allows for linker scripts to assign a new value
to a symbol that is already defined (either in an object file
or the linker script itself).

llvm-svn: 291459
2017-01-09 18:36:57 +00:00
Rui Ueyama ec1c75e059 Add linker-script-included files to reproduce tar files.
Previously, files added using INCLUDE directive weren't added
to reproduce archives. In this patch, I defined a function to
open a file and use that from Driver and LinkerScript.

llvm-svn: 291413
2017-01-09 01:42:02 +00:00
Rafael Espindola 337139830e Change which input sections we concatenate
After Mark's patch I was wondering what was the rationale for the ELF
spec requiring us to merge only sections with matching flags and
types. I tried emailing
https://groups.google.com/forum/#!forum/generic-abi, but looks like my
emails are not being posted (the list is probably moderated). I
emailed Cary Coutant instead.

Cary pointed out that the section was a late addition and didn't got
the scrutiny it deserved. Given that and the problems found by
implementing the letter of the standard, I propose changing lld to
merge all sections with the same name and issue errors if the types or
some critical flags are different.

This should allow an unmodified firefox linked with lld to run.

This also merges some code with the linkerscript path.

llvm-svn: 291107
2017-01-05 14:20:35 +00:00
Rui Ueyama 58841b45d0 Remove Driver::OwningMB and instead use make().
We managed new MemoryBuffers in different ways in LinkerScript.cpp and
Driver.cpp. With this patch, they are managed in the same way.

llvm-svn: 290411
2016-12-23 03:19:09 +00:00
Eugene Leviant f6aeed3624 [ELF] Linkerscript: print location of undefined symbol usage
Differential revision: https://reviews.llvm.org/D27194

llvm-svn: 290339
2016-12-22 13:13:12 +00:00
George Rimar d450065308 [ELF] - Linkerscript: Fall back to search paths when INCLUDE not found
From https://sourceware.org/binutils/docs/ld/File-Commands.html:
The file will be searched for in the current directory, and in any 
directory specified with the -L option.

Patch done by Alexander Richardson.

Differential revision: https://reviews.llvm.org/D27831

llvm-svn: 290247
2016-12-21 09:42:25 +00:00
Rui Ueyama 4f2f50dc64 De-template DefinedSynthetic.
DefinedSynthetic is not created for a real ELF object, so it doesn't
have to be a template function. It has a virtual st_value, which is
either 32 bit or 64 bit, but we can simply use 64 bit.

llvm-svn: 290241
2016-12-21 08:40:09 +00:00
George Rimar 4fb6e79c65 [ELF] - Fix use of freed memory.
It was revealed by D27831.

If we have linkerscript that includes another one that sets OUTPUT for example:

RUN: echo "INCLUDE \"foo.script\"" > %t.script
RUN: echo "OUTPUT(\"%t.out\")" > %T/foo.script
then we do:

void ScriptParser::readInclude() {
...
  std::unique_ptr<MemoryBuffer> &MB = *MBOrErr;
  tokenize(MB->getMemBufferRef());
  OwningMBs.push_back(std::move(MB));
}

void ScriptParser::readOutput() {
...
    Config->OutputFile = unquote(Tok);
...
}
Problem is that OwningMBs are destroyed after script parser do its job.
So all Toks are dead and Config->OutputFile points to destroyed data.

Patch suggests to save all included scripts into using string Saver.

Differential revision: https://reviews.llvm.org/D27987

llvm-svn: 290238
2016-12-21 08:11:49 +00:00
Rafael Espindola 5967c97323 Fix corner cases of setting the section address.
This handles all the corner cases if setting a section address:

- If the address is too low, we cannot allocate the program headers.
- If the load address is lowered, we have to do that before finalize

This also shares some code with the linker script since it was already
hitting similar cases.

This is used by the freebsd boot loader. It is not clear if we need to
support this with a non binary output, but it is not as bad as I was
expecting.

llvm-svn: 290136
2016-12-19 21:21:07 +00:00
Rafael Espindola 17cb7c0a2a Detemplate PhdrEntry. NFC.
llvm-svn: 290115
2016-12-19 17:01:01 +00:00
Rui Ueyama 9381eb1045 Remove lld/Support/Memory.h.
I thought for a while about how to remove it, but it looks like we
can just copy the file for now. Of course I'm not happy about that,
but it's just less than 50 lines of code, and we already have
duplicate code in Error.h and some other places. I want to solve
them all at once later.

Differential Revision: https://reviews.llvm.org/D27819

llvm-svn: 290062
2016-12-18 14:06:06 +00:00
Rui Ueyama 5d804dc8f7 [ELF] - Linkerscript: Implement two argument version of ALIGN()
Fixes http://llvm.org/PR31129

Patch by Alexander Richardson!

Differential Revision: https://reviews.llvm.org/D27848

llvm-svn: 289968
2016-12-16 18:19:35 +00:00
George Rimar 93c64025fc [ELF] - Apply format. NFC.
llvm-svn: 289823
2016-12-15 15:38:09 +00:00
George Rimar 14460e0216 [ELF] - Do not crash when move location counter backward.
PR31335 shows that we do that in next case:
SECTIONS { .text 0x2000 : {. = 0x100 ; *(.text) } }

though documentations says that "If . is used inside a section 
description however, it refers to the byte offset from the start
of that section, not an absolute address. " looks does not work 
as documented in bfd (as mentioned in comments for PR31335).

Until we find out the expected behavior was suggested at least not
to 'crash', what we do after trying to generate huge file.

Differential revision: https://reviews.llvm.org/D27712

llvm-svn: 289782
2016-12-15 07:27:28 +00:00
Rafael Espindola 1ef90d2f25 Fix parsing when one extern follows another.
llvm-svn: 289224
2016-12-09 16:44:05 +00:00
Meador Inge 95c7d8d2a7 [ELF] Allow output section data commands to take expressions
The current implementation of the output section data store commands
can only handle integer literals, but it should really handle arbitrary
expressions [1].  This commit fixes that.

[1] https://sourceware.org/binutils/docs-2.27/ld/Output-Section-Data.html#Output-Section-Data

Differential Revision: https://reviews.llvm.org/D27561

llvm-svn: 289152
2016-12-08 23:21:30 +00:00
Rui Ueyama 520d9169e6 Move Memory.{h,cpp} to lld/Support so that we can use them from COFF.
llvm-svn: 289084
2016-12-08 18:31:13 +00:00
Rafael Espindola d0ebd84c42 Change the implementation of --dynamic-list to use linker script parsing.
The feature is documented as
-----------------------------
The format of the dynamic list is the same as the version node
without scope and node name.  See *note VERSION:: for more
information.
--------------------------------

And indeed qt uses a dynamic list with an 'extern "C++"' in it. With
this patch we support that

The change to gc-sections-shared makes us match bfd. Just because we
kept bar doesn't mean it has to be in the dynamic symbol table.

The changes to invalid-dynamic-list.test and reproduce.s are because
of the new parser.

The changes to version-script.s are the only case where we change
behavior with regards to bfd, but I would like to see a mix of
--version-script and --dynamic-list used in the wild before
complicating the code.

llvm-svn: 289082
2016-12-08 17:54:26 +00:00
Rafael Espindola 7e71415cb3 Add support for 'extern "C"'.
It is used by Qt.

llvm-svn: 289074
2016-12-08 17:26:53 +00:00
Rafael Espindola 41217616a8 Delete dead code.
Thanks to George Rimar for pointing it out.

llvm-svn: 289020
2016-12-08 03:17:05 +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
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
Rui Ueyama b5f1c3ec0c Make get{Line,Column}Number members of StringParser.
This patch also renames currentLocation getCurrentLocation.

llvm-svn: 288308
2016-12-01 04:36:49 +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
George Rimar 18a3096282 [ELF] - Set Config->SingleRoRx differently. NFC.
Previously Config->SingleRoRx was set in
createFiles() and used HasSections.

This change moves it to readConfigs at place of
common flags handling, and adds logic that sets
this flag separatelly from ScriptParser if SECTIONS present.

llvm-svn: 288021
2016-11-28 10:11:10 +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 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 22375f2406 Remove a parameter from ScriptParser.
llvm-svn: 287944
2016-11-25 18:51:54 +00:00
Rui Ueyama f373dd76ce Remove HasError and use ErrorCount instead.
HasError was always true if ErrorCount > 0, so we can use ErrorCount instead.

llvm-svn: 287849
2016-11-24 01:43:21 +00:00
Meador Inge b2d99d6a0f [ELF] Allow `ASSERT` in output section descriptions
GNU LD allows `ASSERT` commands to be in output section descriptions.
Note that LD also mandates that `ASSERT` commands in this context must
end with a semicolon.

llvm-svn: 287677
2016-11-22 18:01:50 +00:00
Rafael Espindola 28d5f059ae Use the correct page size.
Config->MaxPageSize is what we use for the segment alignment, so that
is the one that we have to use for placing the header.

llvm-svn: 287569
2016-11-21 20:20:04 +00:00
Rafael Espindola 1c57007ec8 Fix address computation for headers.
If the linker script has SECTIONS, the address computation is now
always done in LinkerScript::assignAddresses, like for any other
section.

Before fixHeaders would do a tentative computation that
assignAddresses would sometimes override.

This patch also splits the cases where assignAddresses needs to add
the headers to the first PT_LOAD and the address computation. The net
effect is that we no longer create an empty page for no reason in the
included test case, which matches bfd behavior.

llvm-svn: 287565
2016-11-21 19:59:33 +00:00
Eugene Leviant 03ff016666 [ELF] Better error reporting for linker scripts
Differential revision: https://reviews.llvm.org/D26795

llvm-svn: 287547
2016-11-21 15:49:56 +00:00
Rui Ueyama 0b1b695a9e Add comments.
This patch rearranges code a bit to make it easy to explain.

llvm-svn: 287515
2016-11-21 02:11:05 +00:00
Rui Ueyama e0be2901cd Simplify. NFC.
llvm-svn: 287514
2016-11-21 02:10:12 +00:00
Rui Ueyama f94efdddc0 Add a flag to InputSectionBase for linker script.
Previously, we set (uintptr_t)-1 to InputSectionBase::OutSec to record
that a section has already been set to be assigned to some output section
by linker scripts. Later, we restored nullptr to the pointer to use
the field for the original purpose. That overloading is not very easy to
understand.

This patch adds a bit flag for that purpose, so that we don't need
to piggyback the flag on an unrelated pointer.

llvm-svn: 287508
2016-11-20 23:15:52 +00:00
Rui Ueyama 061f9286df Use Optional<std::string> instead of "" to represent a failure.
llvm-svn: 287456
2016-11-19 19:23:58 +00:00
Rui Ueyama 6e68c5e5cf Simplify. NFC.
llvm-svn: 287446
2016-11-19 18:05:58 +00:00
Rui Ueyama 16068aeb58 Change filler type from ArrayRef<uint8_t> to uint32_t.
Filler expressions in linker script "=fillexp" are always handled
as 32-bit integers. Thus the new type is more natural.

llvm-svn: 287445
2016-11-19 18:05:56 +00:00
Rui Ueyama f8f6f1e783 Update comment.
llvm-svn: 287325
2016-11-18 07:03:56 +00:00
Rui Ueyama 009d174229 Omit empty parameter list.
llvm-svn: 287324
2016-11-18 06:49:09 +00:00
Rui Ueyama 46247b85be Use consume() instead of peek() and skip().
llvm-svn: 287323
2016-11-18 06:49:07 +00:00
Rui Ueyama 12450b20b4 Split ScriptParser::readVersionDeclaration.
readVersionDeclaration was to read anonymous version definition and
named version definition. Splitting it into two functions should
improve readability as the two cases are different enough.

I also changed a few helper functions to return values instead of
mutating given references.

llvm-svn: 287319
2016-11-18 06:30:09 +00:00
Rui Ueyama edf75e7992 Allow SIZEOF() command on nonexistent section.
Linker script doesn't create a section if it has no content. So the following
script doesn't create .norelocs section if it doesn't have any .rel* sections.

  .norelocs : { *(.rel*) }

Later, if you assert that the size of .norelocs is 0, LLD printed out
an error message, because it didn't allow calling SIZEOF() on nonexistent
sections.

This patch allows SIZEOF() on nonexistent sections, so that you can do
something like this.

  ASSERT(SIZEOF(.norelocs), "shouldn't contain .rel sections!")

Note that this behavior is compatible with GNU.

Differential Revision: https://reviews.llvm.org/D26810

llvm-svn: 287257
2016-11-17 20:27:10 +00:00
Rafael Espindola d8b81d6663 Avoid accessing an end() iterator.
llvm-svn: 287225
2016-11-17 14:18:08 +00:00
Rui Ueyama 0ee25a6973 Simplify and use consistent variable name. NFC.
llvm-svn: 287200
2016-11-17 03:52:14 +00:00
Rui Ueyama da805c4800 Use uint16_t instead of size_t for symbol version ID.
Because it is uint16_t in the ELF spec. Using size_t was confusing.

llvm-svn: 287198
2016-11-17 03:39:21 +00:00
George Rimar 17c65af82f [ELF] - Separate locals list from versions.
This change separates all versioned locals to be a separate list in config,
that was suggested by Rafael and simplifies the logic a bit.

Differential revision: https://reviews.llvm.org/D26754

llvm-svn: 287132
2016-11-16 18:46:23 +00:00