Commit Graph

437 Commits

Author SHA1 Message Date
Rafael Espindola 06f4743a48 Handle symbol assignments before the first section switch.
We now create a dummy section with index 1 before processing the
linker script.

Thanks to George Rimar for finding the bug and providing the initial
testcase.

llvm-svn: 294252
2017-02-06 22:21:46 +00:00
Rafael Espindola 2b07455315 Simplify. NFC.
Now that each OutputSectionCommand maps to just one OutputSection, we
can remove a few std::vectors.

llvm-svn: 294060
2017-02-03 22:27:05 +00:00
Rafael Espindola 4524268c02 Handle numbers followed by ":" in linker scripts.
This is a fix for Bugzilla 31813.

The problem is that the tokenizer does not create a separate token for
":" unless there's white space before it. Changed it to always create
a token for ":" and reworked some logic that relied on ":" being
attached to some tokens like "global:" and "local:".

llvm-svn: 294006
2017-02-03 13:24:01 +00:00
Rui Ueyama 6697ec293c Update comments.
llvm-svn: 293963
2017-02-02 23:26:12 +00:00
George Rimar 697507556a [ELF] - Recommit r293749. Improve comment. NFC.
llvm-svn: 293751
2017-02-01 09:14:22 +00:00
George Rimar 091f9b35c7 [ELF] - Revert r293749
Accidentally lost the commit title and message,
will recommit.

llvm-svn: 293750
2017-02-01 09:12:29 +00:00
George Rimar f46e54f078 (no commit message)
llvm-svn: 293749
2017-02-01 09:05:45 +00:00
George Rimar cc4d3e5745 [ELF] - Linkerscript: properly mark minus expression with non-absolute flag
This is alternative to D28857 which was incorrect.

One of linux scripts contains:

vvar_start = . - 2 * (1 << 12);
vvar_page = vvar_start;
vvar_vsyscall_gtod_data = vvar_page + 128;
Previously we did not mark first expression as non-absolute,
though it contains location counter.

And LLD failed with error:
relocation R_X86_64_PC32 cannot refer to absolute symbol

This patch should fix the issue, and opens road for doing the same for other operators
(though not clear if that is needed).

Differential revision: https://reviews.llvm.org/D29332

llvm-svn: 293748
2017-02-01 09:01:16 +00:00
George Rimar 2fe079233b [ELF] - Linkerscript: do not fail on additional semicolons in linkerscript.
Linux kernel linkerscript contains additional semicolon (last line):

.apicdrivers : AT(ADDR(.apicdrivers) - LOAD_OFFSET) {
  __apicdrivers = .;
  *(.apicdrivers);

I checked that both gold and bfd are able to parse something like:

.text : { ;;*(.text);;S = 0;; } }

Patch do the same.

Differential revision: https://reviews.llvm.org/D29276

llvm-svn: 293612
2017-01-31 08:50:11 +00:00
Rafael Espindola fe12450e8e Revert commits r293276 and r293278.
[ELF] Fixed formatting. NFC

and

    [ELF] Bypass section type check

    Differential revision: https://reviews.llvm.org/D28761

They do the opposite of what was asked for in the code review.

llvm-svn: 293320
2017-01-27 18:39:30 +00:00
Eugene Leviant 8b7cadcf96 [ELF] Bypass section type check
Differential revision: https://reviews.llvm.org/D28761

llvm-svn: 293276
2017-01-27 11:01:43 +00:00
Rui Ueyama 8a8a953e99 Rename NotFlags -> NegFlags.
Negative flags are still bit flags, so I think "not flag" is a very good name.

llvm-svn: 293143
2017-01-26 02:58:59 +00:00
Rui Ueyama 481ac9967b Use StringRef::lower only once instead of calling ::tolower many times.
llvm-svn: 293142
2017-01-26 02:58:39 +00:00
Rui Ueyama 24e626cc76 Split ScriptParser::readMemory.
llvm-svn: 293141
2017-01-26 02:58:19 +00:00
Meador Inge b889744e5b [LinkerScript] Implement `MEMORY` command
As specified here:

* https://sourceware.org/binutils/docs/ld/MEMORY.html#MEMORY

There are two deviations from what is specified for GNU ld:

  1. Only integer constants and *not* constant expressions
     are allowed in `LENGTH` and `ORIGIN` initializations.

  2. The `I` and `L` attributes are *not* implemented.

With (1) there is currently no easy way to evaluate integer
only constant expressions.  This can be enhanced in the
future.

With (2) it isn't clear how these flags map to the `SHF_*`
flags or if they even make sense for an ELF linker.

Differential Revision: https://reviews.llvm.org/D28911

llvm-svn: 292875
2017-01-24 02:34:00 +00:00
George Rimar 8e2eca229e [ELF] - Linkerscripts: ignore CONSTRUCTORS in output section declaration.
It is used in linux kernel script:
http://lxr.free-electrons.com/source/arch/x86/kernel/vmlinux.lds.S#L140

Though CONSTRUCTORS is ignored for ELF.

Differential revision: https://reviews.llvm.org/D28951

llvm-svn: 292777
2017-01-23 09:36:19 +00:00
Rafael Espindola 8c495e20bd Reduce code duplication when allocating program headers.
This will simplify a bug fix.

llvm-svn: 292642
2017-01-20 20:41:18 +00:00
George Rimar 60aed44387 [ELF] - Do not crash when assign common symbol's values in script
Found that during attempts of linking linux kernel,
previously we partially duplicated code from getOutputSection(),
and it missed commons symbol case.

Differential revision: https://reviews.llvm.org/D28903

llvm-svn: 292594
2017-01-20 09:45:36 +00:00
George Rimar 7185a1acec [ELF] - Support optional comma after output section command.
I found this when tried to link linux kernel with LLD:

https://github.com/torvalds/linux/blob/master/arch/x86/entry/vdso/vdso-layout.lds.S#L86

Output section command can have optional comma at the end:

.text		: { *(.text*) }			:text	=0x90909090,

It was documented about 3 years ago for binutils:
https://sourceware.org/ml/binutils/2014-04/msg00045.html

Differential revision: https://reviews.llvm.org/D28803

llvm-svn: 292225
2017-01-17 15:32:12 +00:00
Rafael Espindola e999ddb8de Add support for anonymous local symbols.
This actually simplifies the code a bit as now all local symbols are
handled uniformly.

This should fix the build of www/webkit2-gtk3.

llvm-svn: 291569
2017-01-10 16:37:24 +00:00
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