Commit Graph

211 Commits

Author SHA1 Message Date
Rui Ueyama d57e74b7d3 Compute Config member function return values only once.
We had a few Config member functions that returns configuration values.
For example, we had is64() which returns true if the target is 64-bit.
The return values of these functions are constant and never change.

This patch is to compute them only once to make it clear that they'll
never change.

llvm-svn: 298168
2017-03-17 23:29:01 +00:00
Rui Ueyama fd06b73466 Define Config::isLE and Config::wordsize.
isLE() return true if the target is little-endian.
wordsize() returns 8 for 64-bit and 4 for 32-bit.

llvm-svn: 298167
2017-03-17 23:28:41 +00:00
Bob Haarman f790f788b6 recommend using llvm-ar when finding undefined references and empty archives
Summary:
When we perform LTO builds with a version of ar that does not
understand LLVM bitcode objects, we end up with undefined references,
because our archive files do not list the bitcode symbols in their
indices. The error messages do not make it clear what the real problem
is. This change adds a note that points out the likely problem and
solution. It is similar in spirit to r282633, but aims to avoid false
positives by only triggering when we see both undefined references and
archives without symbols in their indices.

Fixes PR32281.

Reviewers: davide, ruiu, tejohnson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D31011

llvm-svn: 298124
2017-03-17 21:32:49 +00:00
Peter Collingbourne ee59e43f92 ELF: Add cache pruning support.
This patch causes us to use pruneCache() to prune the ThinLTO cache after
completing LTO. A new flag --thinlto-cache-policy allows users to configure
the policy.

Differential Revision: https://reviews.llvm.org/D31021

llvm-svn: 298036
2017-03-17 02:24:16 +00:00
George Rimar 7385d4358a [ELF] - Rename Config->Is64Bit() to is64(). NFC.
Addresses post commit review comment.

llvm-svn: 297953
2017-03-16 13:41:29 +00:00
George Rimar 10f74fc10b [ELF] - Detemplate GotPltSection and IgotPltSection sections.
Patch introduces Config->is64Bit() and with help of that detemplates
GotPltSection and IgotPltSection sections

Differential revision: https://reviews.llvm.org/D30944

llvm-svn: 297813
2017-03-15 09:12:56 +00:00
Rui Ueyama f5fce48679 Handle ":" as a regular token character in linker scripts.
This is an alternative to https://reviews.llvm.org/D30500 to simplify the
version definition parser and allow ":" in symbol names.

Differential Revision: https://reviews.llvm.org/D30722

llvm-svn: 297402
2017-03-09 19:23:00 +00:00
George Rimar 0a7412f00b [ELF] - Implemented -znotext
gold linker manual describes them as:

-z text	Do not permit relocations in read-only segments
-z notext Permit relocations in read-only segments (default)

In LLD default is to not permit them. Patch implements -z notext.

Differential revision: https://reviews.llvm.org/D30530

llvm-svn: 297366
2017-03-09 08:48:34 +00:00
Rui Ueyama af6198d96d Remove Config->Rela and define Config->isRela() instead.
llvm-svn: 297108
2017-03-07 00:43:53 +00:00
Rui Ueyama df8eb17d21 Remove Config->Mips64EL and define Config->isMips64EL() instead.
llvm-svn: 297107
2017-03-07 00:43:33 +00:00
Peter Collingbourne e02775f068 ELF: Add ThinLTO caching support.
This patch adds an option named --thinlto-cache-dir, which specifies the
path to a directory in which to cache native object files for ThinLTO
incremental builds.

Differential Revision: https://reviews.llvm.org/D30509

llvm-svn: 296702
2017-03-01 23:00:10 +00:00
Martell Malone 6b43b7ad49 [ELF] - Allow the Code Model flag when using LTO
Differential Revision: https://reviews.llvm.org/D29445

llvm-svn: 296542
2017-02-28 23:43:26 +00:00
Rui Ueyama 47926abfa6 Remove a default value that is always overwritten.
llvm-svn: 296230
2017-02-25 02:27:58 +00:00
Rui Ueyama 524d44c6fa Do not handle -strip in a special way. NFC.
llvm-svn: 296227
2017-02-25 02:12:37 +00:00
Rui Ueyama dfa3ad1313 Factor out code to parse -hash-style.
llvm-svn: 296226
2017-02-25 02:07:27 +00:00
Rui Ueyama a37ace8d89 Rename OMagic -> Omagic for consistency.
llvm-svn: 296225
2017-02-25 01:52:03 +00:00
Rui Ueyama f9e8034c9c Add `-z nocopyreloc` option.
This option disable creating copy relocations. ld.bfd and ld.gold
have the same option.

llvm-svn: 295772
2017-02-21 21:41:50 +00:00
Rui Ueyama f9a45628a3 Remove stray semicolon.
llvm-svn: 295077
2017-02-14 17:36:23 +00:00
Rui Ueyama 104e2357de Do not store a computable attributes to Config.
llvm-svn: 295031
2017-02-14 05:45:47 +00:00
Davide Italiano db4b0a7194 [LTO] Add support for optimization remarks.
Differential Revision:  https://reviews.llvm.org/D29878

llvm-svn: 294971
2017-02-13 17:49:18 +00:00
George Rimar 82bd8be6d8 Recommit r294464 "[ELF] - Added partial support for --emit-relocs (no --gc-section case, no /DISCARD/ support) #3"
with temporarily file name fix in testcase.

Original commit message:

-q, --emit-relocs - Generate relocations in output

Simplest implementation: 
* no GC case, 
* no "/DISCARD/" linkerscript command support.

This patch is extracted from D28612 / D29636,

Relative to PR31579.

Differential revision: https://reviews.llvm.org/D29663

llvm-svn: 294469
2017-02-08 16:18:10 +00:00
George Rimar 0b2cc8190d Reverted r294464 "[ELF] - Added partial support for --emit-relocs (no --gc-section case, no /DISCARD/ support) #3"
Broked build bot:
http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast/builds/5835/steps/test/logs/stdio

llvm-svn: 294466
2017-02-08 16:10:14 +00:00
George Rimar d6ae624552 [ELF] - Added partial support for --emit-relocs (no --gc-section case, no /DISCARD/ support) #3
-q, --emit-relocs - Generate relocations in output

Simplest implementation: 
* no GC case, 
* no "/DISCARD/" linkerscript command support.

This patch is extracted from D28612 / D29636,

Relative to PR31579.

Differential revision: https://reviews.llvm.org/D29663

llvm-svn: 294464
2017-02-08 15:53:33 +00:00
Rafael Espindola 403b093eff Fix and simplify the reporting of undefined symbols.
Now reportUndefined only has to look at Config->UnresolvedSymbols and
the symbol. getUnresolvedSymbolOption does all the hard work of
mapping options like -shared and -z defs to one of the
UnresolvedPolicy enum entries.

The critical fix is that now "-z defs --warn-unresolved-symbols" only
warns.

llvm-svn: 293290
2017-01-27 15:52:08 +00:00
Rafael Espindola c0fc253071 Change the --retain-symbols-file implementation.
It now uses the same infrastructure as symbol versions. This fixes us
creating a dynamic relocation without a corresponding dynamic symbol.

This also means that unlike gold and bfd we keep a STB_LOCAL in the
static symbol table. It seems an odd feature to offer precise control
over what is in a symbol table that is not used by the dynamic
linker. We can bring this back if needed, but it would probably be
better to just have --discard option that tells the linker to keep in
the static symbol table only what is in the dynamic one.

Should fix the eog build.

llvm-svn: 293093
2017-01-25 21:23:06 +00:00
Rui Ueyama b2a23cf3c0 Do not allocate space for common symbols with -r
Currently ld.lld -r allocates space for common symbols, whereas ld.bfd
-r doesn't.  As a result the OpenBSD makefile bits for creating libraries
fail as they use ld -X -r to strip local symbols, which results in
duplicate symbol errors because space for the common symbols has been
allocated.

The diff also implements the --define-commons option such that allocation
of commons can be forced even if -r is used.

Patch by Mark Kettenis.

llvm-svn: 292878
2017-01-24 03:41:20 +00:00
Rafael Espindola 1ebfc59c89 Implement -Map.
The format is not exactly the same as the one in bfd since bfd always
follows a linker script and prints it along.

llvm-svn: 291958
2017-01-13 21:05:46 +00:00
Rui Ueyama 312703116f Simplify type of Config->SymbolOrderingFile.
That variable was of type DenseMap<StringRef, unsigned>, but the
unsigned numbers needed to be monotonicly increasing numbers because
the implementation that used the variable depended on that fact.
That was an implementation detail and shouldn't have leaked into Config.

This patch simplifies its type to std::vector<StringRef>.

llvm-svn: 290151
2016-12-20 01:51:08 +00:00
George Rimar 2bb88ab5e0 [ELF] - Implemented --retain-symbols-file option
--retain-symbols-file=filename
Retain only the symbols listed in the file filename, discarding all others. 
filename is simply a flat file, with one symbol name per line. This option 
is especially useful in environments (such as VxWorks) where a large global 
symbol table is accumulated gradually, to conserve run-time memory.

Note: though documentation says "--retain-symbols-file does not discard 
undefined symbols, or symbols needed for relocations.", both bfd and gold 
do that, and this patch too, like testcase show.

Differential revision: https://reviews.llvm.org/D27716

llvm-svn: 290122
2016-12-19 18:00:52 +00:00
Rui Ueyama 8f687f71fb Remove inappropriate use of CachedHashStringRef.
Use of CachedHashStringRef makes sense only when we reuse hash values.
Sprinkling it to all DenseMap has no benefits and just complicates data types.
Basically we shouldn't use CachedHashStringRef unless there is a strong
reason to to do so.

llvm-svn: 290076
2016-12-19 03:14:16 +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
Rui Ueyama 9e5f5effe5 Make a decision about whether we should warn on missing entry or not early.
Config->WarnMissingEntry is a single-purpose boolean variable, and
I think it's easier to understand than Config->HasEntry.

llvm-svn: 288883
2016-12-07 04:06:21 +00:00
Rui Ueyama a1407c4fdf Simplify -e <number> option handling.
This patch is to parse the entry symbol name lazily.

llvm-svn: 288882
2016-12-07 03:23:06 +00:00
Petr Hosek 2f50fef095 [ELF] Shared libraries should have entry point
Shared libraries should have entry set following the same rules as for
regular binaries. The only difference is that in case the default entry
point (_start or __start) isn't found (unless it was set explicitly), we
shouldn't give a warning as in case of regular binaries.

Differential Revision: https://reviews.llvm.org/D27497

llvm-svn: 288878
2016-12-07 02:26:16 +00:00
George Rimar 595a763f38 [ELF] - Implemented -N (-omagic) command line option.
-N (-omagic)
  Set the text and data sections to be readable and writable. 
  Also, do not page-align the data segment.

Differential revision: https://reviews.llvm.org/D26888

llvm-svn: 288123
2016-11-29 09:43:51 +00:00
George Rimar 63bf011003 [ELF] - Implemented -no-rosegment.
--no-rosegment: Do not put read-only non-executable sections in their own segment

Differential revision: https://reviews.llvm.org/D26889

llvm-svn: 288020
2016-11-28 10:05:20 +00:00
Rui Ueyama 72b1ee2533 Make getColorDiagnostics return a boolean value instead of an enum.
Config->ColorDiagnostics was of type enum before. Now it is just a
boolean flag. Thanks Rafael for suggestion.

llvm-svn: 287978
2016-11-26 15:10:01 +00:00
Davide Italiano 3bfa081aa9 [ELF] Be compliant with LLVM and rename Lto into LTO. NFCI.
llvm-svn: 287967
2016-11-26 05:37:04 +00:00
Rui Ueyama 8c8818a58c Support -color-diagnostics={auto,always,never}.
-color-diagnostics=auto is default because that's the same as
Clang's default. When color is enabled, error or warning messages
are colored like this.

  error:
  <bold>ld.lld</bold> <red>error:</red> foo.o: no such file

  warning:
  <bold>ld.lld</bold> <magenta>warning:</magenta> foo.o: no such file

Differential Revision: https://reviews.llvm.org/D27117

llvm-svn: 287949
2016-11-25 20:27:32 +00:00
Rui Ueyama 1b591cf3d3 Fix uninitialized variable access.
llvm-svn: 287797
2016-11-23 19:03:35 +00:00
Rui Ueyama ac95f6bfcc Limit default maximum number of errors to 20.
This is in the context of https://llvm.org/bugs/show_bug.cgi?id=31109.
When LLD prints out errors for relocations, it tends to print out
extremely large number of errors (like millions) because it would
print out one error per relocation.

This patch makes LLD bail out if it prints out more than 20 errors.
You can configure the limitation using -error-limit argument.
-error-limit=0 means no limit.

I chose the flag name because Clang has the same feature as -ferror-limit.
"f" doesn't make sense to us, so I omitted it.

Differential Revision: https://reviews.llvm.org/D26981

llvm-svn: 287789
2016-11-23 18:15:37 +00:00
Rui Ueyama 8980c92dde Use consistent variable name.
llvm-svn: 287318
2016-11-18 06:30:08 +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
George Rimar bb6c01e7c3 [ELF] - Add support for locals list in version script.
Previously we did not support anything except "local: *", patch changes that.

Actually GNU rules of proccessing wildcards are more complex than that (http://www.airs.com/blog/archives/300):
There are 2 iteration for wildcards, at first iteration "*" wildcards are ignored and handled at second iteration.

Since we previously decided not to implement such complex rules,
I suggest solution that is implemented in this patch. So for "local: *" case nothing changes,
but if we have wildcarded locals,
they are processed before wildcarded globals. 

This should fix several FreeBSD ports, one of them is jpeg-turbo-1.5.1 and
currently blocks about 5k of ports.

Differential revision: https://reviews.llvm.org/D26395

llvm-svn: 286713
2016-11-12 07:04:15 +00:00
George Rimar 1a33c0f242 [ELF] - Implemented --symbol-ordering-file option.
Patch allows to pass a symbols file to linker.
LLD will map symbols to sections and sort sections
in output according to symbol ordering file.

That can help to reduce the startup time and/or
amount of pagefaults during startup.

Also, interesting benchmark result was produced by Rafael Espíndola. 
After applying the symbols file for clang he timed compiling 
X86MCTargetDesc.ii to an object file.  

The page faults went from just
56,988 to 56,946 since most faults are not in the binary.
Running time went from 4.403053515 to 4.178112244. 
The speedup seems to be because of better cache
locality.

Differential revision: https://reviews.llvm.org/D26130

llvm-svn: 286440
2016-11-10 09:05:20 +00:00
Simon Atanasyan 9e0297b8bc [ELF][MIPS] N32 ABI support
In short the patch introduces support for linking object file conform
MIPS N32 ABI [1]. This ABI is similar to N64 ABI but uses 32-bit
pointer size.

The most non-trivial requirement of this ABI is one more relocation
packing format. N64 ABI puts multiple relocation type into the single
relocation record. The N32 ABI uses series of successive relocations
with the same offset for this purpose. In this patch, new function
`mergeMipsN32RelTypes` handle this case and "convert" N32 relocation to
the N64 relocation so the rest of the code keep unchanged.

For now, linker does not support series of relocations applied to sections
without SHF_ALLOC bit. Probably later I will add the support or insert
some sort of assert into the `relocateNonAlloc` routine to catch this
case.

[1] ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/MIPS-N32-ABI-Handbook.pdf

Differential revision: https://reviews.llvm.org/D26298

llvm-svn: 286052
2016-11-05 22:58:01 +00:00
Rafael Espindola 7cc713adcb Store OSABI in Config.
This allows us to set a value for it based on -m.

llvm-svn: 285294
2016-10-27 14:00:51 +00:00
Rafael Espindola cb09daab0a Call _exit.
As the state of lld gets more complicated, shutting down gets more
expensive.

In a normal lld run we can just call _exit immediately after renaming
the temporary output file. We still want the ability to run a full
shutdown since that is useful for detecting memory leaks.

This patch adds a --full-shutdown flag and changes lit to use it.

llvm-svn: 285224
2016-10-26 18:59:00 +00:00
George Rimar 58fa5243cc [ELF] - Partial support of --gdb-index command line option (Part 1).
In this patch partial gdb_index section is created. 
For costructing the .gdb_index section 6 steps should be performed (details are in
SplitDebugInfo.cpp file header), this patch do first 3:

Creates proper section header.
Fills list of compilation units.
Types CU list area is not supposed to be supported, so it is ignored and therefore
can be treated as implemented either.

Differential revision: https://reviews.llvm.org/D24706

llvm-svn: 284708
2016-10-20 09:19:48 +00:00