Commit Graph

410 Commits

Author SHA1 Message Date
Rafael Espindola c65aee64ec Add two helper functions. NFC.
llvm-svn: 289064
2016-12-08 15:56:33 +00:00
Rafael Espindola 39c16dfbce Simplify. NFC.
llvm-svn: 289062
2016-12-08 15:36:58 +00:00
Simon Atanasyan 872764f6fe [ELF] Correct addAbsolute function argument name
Follow-up to r289025.

llvm-svn: 289061
2016-12-08 15:29:17 +00:00
Simon Atanasyan 6a4eb75c46 [ELF][MIPS] Make _gp, _gp_disp, __gnu_local_gp global symbols
These MIPS specific symbols should be global because in general they can
have an arbitrary value. By default this value is a fixed offset from .got
section.

This patch adds more checks to the mips-gp-local.s test case but marks
it as XFAIL because LLD does not allow redefinition of absolute symbols
value by a linker script. This should be fixed by D27276.

Differential revision: https://reviews.llvm.org/D27524

llvm-svn: 289025
2016-12-08 06:19:47 +00:00
Rui Ueyama 4c5b8cea02 Make demangle() return None instead of "" if a given string is not a mangled symbol.
llvm-svn: 288993
2016-12-07 23:17:05 +00:00
Rafael Espindola 858c092daa Allow duplicated abs symbols with the same value.
This is a fairly reasonable bfd extension since there is one obvious value.

dtrace depends on this feature as it creates multiple absolute
symbols with the same value.

llvm-svn: 288461
2016-12-02 02:58:21 +00:00
Rui Ueyama a13efc2a73 Introduce StringRefZ class to represent null-terminated strings.
StringRefZ is a class to represent a null-terminated string. String
length is computed lazily, so it's more efficient than StringRef to
represent strings in string table.

The motivation of defining this new class is to merge functions
that only differ in string types; we have many constructors that takes
`const char *` or `StringRef`. With StringRefZ, we can merge them.

Differential Revision: https://reviews.llvm.org/D27037

llvm-svn: 288172
2016-11-29 18:05:04 +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 da06bfb794 Move getLocation from Relocations.cpp to InputSection.cpp.
The function was used only within Relocations.cpp, but now we are
using it in many places, so this patch moves it to a file that fits
to the functionality.

llvm-svn: 287943
2016-11-25 18:51:53 +00:00
Rui Ueyama 26081caf48 Use toString() to report incompatible files.
llvm-svn: 287901
2016-11-24 20:59:44 +00:00
Rui Ueyama a3ac17372b Define toString(const SymbolBody &) and remove maybeDemangle instead.
Differential Revision: https://reviews.llvm.org/D27065

llvm-svn: 287899
2016-11-24 20:24:18 +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
Rui Ueyama 3fc0f7e54f Define toString() as a generic function to get a string for error message.
We have different functions to stringize objects to construct
error messages. For InputFile, we have getFilename, and for
InputSection, we have getName. You had to memorize them.

I think this is the case where the function overloading comes in handy.

This patch defines toString() functions that are overloaded for all these
types, so that you just call it in error().

Differential Revision: https://reviews.llvm.org/D27030

llvm-svn: 287787
2016-11-23 18:07:33 +00:00
Rui Ueyama 0cbf749397 Remove one of SymbolTable::addRegular function that forwards other addRegular.
So that we have less number of overloaded functions.

llvm-svn: 287745
2016-11-23 06:59:47 +00:00
Rui Ueyama 768c6f0ca6 Remove a forwarding constructor that is used only once.
llvm-svn: 287742
2016-11-23 06:31:23 +00:00
Rui Ueyama 35fa6c58ad Parse symbol versions in scanVersionScript() instead of insert().
There are two ways to set symbol versions. One way is to use symbol
definition file, and the other is to embed version names to symbol
names. In the latter way, symbol name is in the form of `foo@version1`
where `foo` is a real name and `version1` is a version.

We were parsing symbol names in insert(). That seems unnecessarily
too early. We can do it later after we resolve all symbols. Doing it
lazily is a good thing because it makes code easier to read
(because now we have a separate pass to parse symbol names). Also
it could slightly improve performance because if two identical symbols
have versions, we now parse them only once.

llvm-svn: 287741
2016-11-23 05:48:40 +00:00
Rui Ueyama 8f47556796 Remove unused #include.
llvm-svn: 287467
2016-11-19 23:18:43 +00:00
Rui Ueyama 8980c92dde Use consistent variable name.
llvm-svn: 287318
2016-11-18 06:30:08 +00:00
Rui Ueyama d84124f043 Add single quotes to error messages.
llvm-svn: 287254
2016-11-17 19:57:47 +00:00
Rui Ueyama 96db27c74f Use consistent variable name.
llvm-svn: 287253
2016-11-17 19:57:45 +00:00
Rui Ueyama cd236a9577 Use llvm::reverse to get a reverse range.
llvm-svn: 287252
2016-11-17 19:57:43 +00:00
Rui Ueyama bac1c3ce85 Pass StringRefs instead of StringMatcher because it's simpler.
llvm-svn: 287234
2016-11-17 16:48:53 +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
Rui Ueyama aade0e29ad Add single quotes to a warning message for consistency.
llvm-svn: 287197
2016-11-17 03:32:41 +00:00
Rui Ueyama 77d917de57 Simplify handleAnonymousVersion even more.
We used to create a vector contantaining all version definitions
with wildcards because doing that was efficient. All patterns were
compiled to a regexp and matched against symbol names. Because
a regexp can be converted to a DFA, matching against union of patterns
is as cheap as matching against one patter.

We are no longer converting them to regexp. Our own glob pattern
handler doesn't do such optimization. Therefore, creating a vector
no longer makes sense.

llvm-svn: 287196
2016-11-17 03:19:34 +00:00
Rui Ueyama 4162baa4bb Simplify. NFC.
llvm-svn: 287192
2016-11-17 02:16:06 +00:00
Rui Ueyama 94bcfae26d Split scanVersionScript. NFC.
llvm-svn: 287191
2016-11-17 02:09:42 +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
Rafael Espindola 95eae57d78 Don't error if __tls_get_addr is defined.
Turns out some systems do define it. Not producing an error in this
case matches gold and bfd.

llvm-svn: 287125
2016-11-16 18:01:41 +00:00
George Rimar e0fc24210d [ELF] - Added support for extern "c++" local symbols in version script.
Previously we did not support them,
patch implements this functionality

Differential revision: https://reviews.llvm.org/D26604

llvm-svn: 287124
2016-11-16 17:59:10 +00:00
Eugene Leviant afaa934304 [ELF] Add Section() to expression object
This allows making symbols containing ADDR(section) synthetic,
and defining synthetic symbols outside SECTIONS block.

Differential revision: https://reviews.llvm.org/D25441

llvm-svn: 287090
2016-11-16 09:49:39 +00:00
Rui Ueyama 8249214299 Refactor symbol version assignmnt code.
The code to handle symbol versions is getting tricky and hard to
understand, so it is probably time to simplify it. This patch does
the following.

 - Add `DemangledSyms` variable to SymbolTable so that we don't
   need to pass it around to findDemangled.
 - Define `initDemangledSyms` to initialize the variable lazily.
 - hasExternCpp is removed because we no longer have to initialize
   the map eagerly.
 - scanScriptVersion is split.
 - Comments are updated.

llvm-svn: 287002
2016-11-15 18:41:52 +00:00
Rui Ueyama baf7ee3c5e Rename variables of type SymbolVersion.
In this file, `sym` was used for both SymbolBody and SymbolVersion
although the two are completely different.

llvm-svn: 286992
2016-11-15 17:51:09 +00:00
George Rimar 463984d4bf [ELF] - Better diagnostic for relative relocation to an absolute value error.
Patch adds a filename to that error message.

I faced next error when debugged one of FreeBSD port:
error: relocation R_X86_64_PLT32 cannot refer to absolute symbol __tls_get_addr

error message was poor and this patch improves it to show the locations 
of symbol declaration and using.

Differential revision: https://reviews.llvm.org/D26508

llvm-svn: 286940
2016-11-15 08:07:14 +00:00
George Rimar 92ca6f4b7d [ELF] - Fix mistype. NFC.
llvm-svn: 286801
2016-11-14 09:56:35 +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
Teresa Johnson 1e390897ba Mirror the llvm changes that split Bitcode/ReaderWriter.h
The change in D26502 splits ReaderWriter.h, which contains the APIs
into both the BitReader and BitWriter libraries, into BitcodeReader.h
and BitcodeWriter.h.

Change lld uses to the appropriate split header, removing it
completely in one case where it wasn't needed.

llvm-svn: 286568
2016-11-11 05:35:22 +00:00
Rui Ueyama 1bdaf3e30c Remove an overloaded function to simplify.
This version of addRegular is almost identical to the other except
it lacked "size" parameter.

llvm-svn: 286416
2016-11-09 23:37:40 +00:00
Rafael Espindola e08e78df6d Make OutputSectionBase a class instead of class template.
The disadvantage is that we use uint64_t instad of uint32_t for some
value in 32 bit files. The advantage is a substantially simpler code,
faster builds and less code duplication.

llvm-svn: 286414
2016-11-09 23:23:45 +00:00
Rui Ueyama edc183e437 Simplify getLocation() function.
All tests pass without the first parameter, so I guess we don't need it.

Differential Revision: https://reviews.llvm.org/D26411

llvm-svn: 286287
2016-11-08 20:30:19 +00:00
Rui Ueyama 9c5a69d2ac Rename a function to avoid function overloading. NFC.
llvm-svn: 286282
2016-11-08 20:02:23 +00:00
Eugene Leviant 825e538559 [ELF] Better error reporting for duplicate symbol
Differential revision: https://reviews.llvm.org/D26397

llvm-svn: 286244
2016-11-08 16:26:32 +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
Rui Ueyama f91282e1cf Add [<chars>] to the glob matcher to eliminate use of llvm::Regex.
Previously, it didn't support the character class, so we couldn't
eliminate the use fo llvm::Regex. Now that it is supported, we
can remove compileGlobPattern, which converts a glob pattern to
a regex.

This patch contains optimization for exact/prefix/suffix matches.

Differential Revision: https://reviews.llvm.org/D26284

llvm-svn: 285949
2016-11-03 17:57:38 +00:00
George Rimar bcba39ab9c [ELF] - Check that .dynsym is present in DSO if SHT_GNU_versym section is.
When we have SHT_GNU_versym section, it is should be associated with symbol table
section. Usually (and in out implementation) it is .dynsym.
In case when .dynsym is absent (due to broken object for example), 
lld crashes in parseVerdefs() when accesses null pointer:

Versym = reinterpret_cast<const Elf_Versym *>(this->ELFObj.base() +
                                              VersymSec->sh_offset) +
         this->Symtab->sh_info;

DIfferential revision: https://reviews.llvm.org/D25553

llvm-svn: 285796
2016-11-02 10:16:25 +00:00
Rui Ueyama 55518e7dd8 Consolidate BumpPtrAllocators.
Previously, we have a lot of BumpPtrAllocators, but all these
allocators virtually have the same lifetime because they are
not freed until the linker finishes its job. This patch aggregates
them into a single allocator.

Differential revision: https://reviews.llvm.org/D26042

llvm-svn: 285452
2016-10-28 20:57:25 +00:00
Rafael Espindola 093abab817 Don't create a dummy ELF to process a binary file.
Now that it is easy to create input section and symbols, this is
simple.

llvm-svn: 285322
2016-10-27 17:45:40 +00:00
Rafael Espindola 5ceeb60c6e Have on addRegular forward to another. NFC.
Another step in making it easier to create symbols without an ELf_Sym.

llvm-svn: 285241
2016-10-26 20:57:14 +00:00
Rui Ueyama 8fcc3afdd1 Move a helper function that doesn't depend on a class out of the class.
llvm-svn: 285220
2016-10-26 18:28:08 +00:00
Rui Ueyama 5ce977ccd0 Define a helper function to demangle symbols.
llvm-svn: 285219
2016-10-26 18:28:06 +00:00
Rafael Espindola 5da1d88492 Reduce the number of allocators.
We used to have one allocator per file, which reduces the advantage of
using an allocator in the first place.

This is a small speed up is most cases. The largest speedup was in
1.014X in chromium no-gc. The largest slowdown was scylla at 1.003X.

llvm-svn: 285205
2016-10-26 15:34:24 +00:00
Rafael Espindola 8b2c8536e5 Use a CachedHashString for comdats too.
We were already using it in the larger sets/maps. This provides about
1% speedup in linking xul and chromium.

llvm-svn: 284862
2016-10-21 19:49:42 +00:00
George Rimar a4c7e74d4b [ELF] - Applied clang format. NFC.
llvm-svn: 284705
2016-10-20 08:36:42 +00:00
Justin Lebar 3c11e93831 Use CachedHashStringRef instead of CachedHash<StringRef>.
Summary:
This uses one less word on 64-bit platforms, so should be a strict
improvement.  This change also lets us get rid of llvm::CachedHash.

Reviewers: rafael, timshen

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D25646

llvm-svn: 284502
2016-10-18 17:50:36 +00:00
Davide Italiano bcdd6c60a0 [ThinLTO] Avoid archive member collisions.
This fixes PR30665.

Differential Revision:  https://reviews.llvm.org/D25495

llvm-svn: 284034
2016-10-12 19:35:54 +00:00
Rui Ueyama d31e13f287 Rename warning -> warn.
It's better because it's a verb.

llvm-svn: 282763
2016-09-29 21:00:23 +00:00
Davide Italiano 786d8e33db [ELF/LTO] Switch to the new resolution-based API.
Differential Revision:  https://reviews.llvm.org/D24492

llvm-svn: 282656
2016-09-29 00:40:08 +00:00
George Rimar 31c25ae90a Recommit r281318 "[ELF] - Versionscript: support mangled symbols with the same name."
Previouly bot was failing:
http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/413/steps/test-stage1-compiler/logs/stdio
Fixed possible segfault, so commit should bix the buildbot.

Initial commit message:

This is PR30312. Info from bug page:

Both of these symbols demangle to abc::abc():
_ZN3abcC1Ev
_ZN3abcC2Ev
(These would be abc's complete object constructor and base object constructor, respectively.)
however with "abc::abc()" in the version script only one of the two receives the symbol version.

Patch fixes that.
It uses testcase created by Ed Maste (D24306).

Differential revision: https://reviews.llvm.org/D24336

llvm-svn: 281605
2016-09-15 12:44:38 +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
George Rimar 84ba4ae11d revert: [ELF] - Versionscript: support mangled symbols with the same name.
Something broked BBots:
281318 failed on step 9:
http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/413

r281317 built step 9 green:
http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/415

Initial revision commits were:
This is PR30312. Info from bug page:

Both of these symbols demangle to abc::abc():
_ZN3abcC1Ev
_ZN3abcC2Ev
(These would be abc's complete object constructor and base object constructor, respectively.)
however with "abc::abc()" in the version script only one of the two receives the symbol version.

Patch fixes that.
It uses testcase created by Ed Maste (D24306).

Differential revision: https://reviews.llvm.org/D24336

llvm-svn: 281411
2016-09-13 22:26:12 +00:00
Rui Ueyama ea26504c19 Split scanVersionScript. NFC.
llvm-svn: 281393
2016-09-13 20:51:30 +00:00
Rui Ueyama fbde710497 Add comments.
llvm-svn: 281388
2016-09-13 20:41:06 +00:00
George Rimar e2051efcbe [ELF] - Versionscript: support mangled symbols with the same name.
This is PR30312. Info from bug page:

Both of these symbols demangle to abc::abc():
_ZN3abcC1Ev
_ZN3abcC2Ev
(These would be abc's complete object constructor and base object constructor, respectively.)
however with "abc::abc()" in the version script only one of the two receives the symbol version.

Patch fixes that.
It uses testcase created by Ed Maste (D24306).

Differential revision: https://reviews.llvm.org/D24336

llvm-svn: 281318
2016-09-13 10:45:39 +00:00
Michael J. Spencer 0cb8a70adc [ELF] Fix memory leak in BinaryFile handling.
llvm-svn: 281129
2016-09-10 01:42:43 +00:00
Michael J. Spencer a9424f39c4 [ELF] Add support for -b binary
Implemented by building an ELF file in memory.

elf, default, and binary match gold behavior.

Differential Revision: https://reviews.llvm.org/D24060

llvm-svn: 281108
2016-09-09 22:08:04 +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
Rafael Espindola 868fc9279e Handle globs in global symbol names.
Fixes pr28775.

llvm-svn: 280947
2016-09-08 14:50:55 +00:00
Rui Ueyama dad2b88c7d Update comments.
llvm-svn: 280548
2016-09-02 22:15:08 +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
Rafael Espindola 0509876f3f Remove redundant argument. NFC.
llvm-svn: 280243
2016-08-31 13:49:23 +00:00
Rafael Espindola 8db87291ef Internalize common variables.
Before this lld was always creating common symbols itself. It worked,
but prevented them from being internalized when possible.

Now it preserves common symbols is the bitcode and they are internalized.

Fixes pr30184.

llvm-svn: 280242
2016-08-31 13:42:08 +00:00
Rafael Espindola e7553e4eac Delete unnecessary template.
llvm-svn: 280237
2016-08-31 13:28:33 +00:00
Rafael Espindola a6c9744a6c Delete DefinedBitcode.
Given that we almost always want to handle it as DefinedRegular, just
use DefinedRegular.

llvm-svn: 280226
2016-08-31 12:30:34 +00:00
Rafael Espindola cceb92a075 Pass Binding instead of IsWeak to addBitcode.
We were computing the binding on both the caller and callee.

llvm-svn: 280156
2016-08-30 20:53:26 +00:00
Davide Italiano 35af5b3d21 [LTO] Fix the logic for dropping unnamed_addr.
Differential Revision:  https://reviews.llvm.org/D24037

llvm-svn: 280144
2016-08-30 20:15:03 +00:00
George Rimar 7af6452927 [ELF] - Use early return. NFC.
This addresses forgotten review comment for r280067:
"[ELF] - Versionscript: support wildcards for extern "c++" tag."

llvm-svn: 280068
2016-08-30 09:39:36 +00:00
George Rimar 397cd87a69 [ELF] - Versionscript: support wildcards for extern "c++" tag.
Previously for extern keyword only names in quotes (exact match) was supported.
Patch adds support for wildcards, so next scripts can be handled properly:

LIBSAMPLE_1.0 {
   global:            
     extern "C++" {  
       foo*;   
   };                  
 };

Differential revision: https://reviews.llvm.org/D23794

llvm-svn: 280067
2016-08-30 09:35:03 +00:00
George Rimar c3ec9d0cbf [ELF] - Cleanup of scanVersionScript(): do not change local Demangled variable. NFC.
llvm-svn: 280066
2016-08-30 09:29:37 +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
Eugene Leviant 3e6b027705 [ELF] Allows setting section for common symbols in linker script
llvm-svn: 277023
2016-07-28 19:24:13 +00:00
Rui Ueyama dace838138 Simplify symbol version handling.
r275711 for "speedng up symbol version handling" was committed
by misunderstanding; the benchmark number was measured with
a debug build. The number with a release build didn't actually change.
This patch removes false optimizations added in that patch.

llvm-svn: 276267
2016-07-21 13:13:21 +00:00
George Rimar b084125dbf [ELF] - Fixed integral constant overflow warning under MSVS 2015. NFC.
Under MSVS 2015 I observed integral constant overflow warning when aggregate initialization was used
to init the bit field. Patch fixes that.

llvm-svn: 276118
2016-07-20 14:26:48 +00:00
Rui Ueyama e33579072d Remove SymbolBody::PlaceholderKind.
In the last patch for --trace-symbol, I introduced a new symbol type
PlaceholderKind and store it to SymVector storage. It made all code
that iterates over SymVector to recognize and skip PlaceholderKind
symbols. I found that that's annoying.

In this patch, I removed PlaceholderKind and stop storing them to SymVector.
Now the information whether a symbol is being watched by --trace-symbol
is stored to the Symtab hash table.

llvm-svn: 275747
2016-07-18 01:35:00 +00:00
Rui Ueyama d6328526ba Iterate over SymVector instead of Symtab hash table.
SymVector contains all symbols, so we can iterate either Symtab or SymVector
to visit all symbols. Iterating over SymVector makes the next change for
--trace-symbol possible.

llvm-svn: 275746
2016-07-18 01:34:57 +00:00
Rui Ueyama 69c778c084 Implement almost-zero-cost --trace-symbol.
--trace-symbol is a command line option to watch a symbol.
Previosly, we looked up a hash table for a new symbol if the
option is given. Any code that looks up a hash table for each
symbol is expensive because the linker handles a lot of symbols.
In our design, we look up a hash table strictly only once
for a symbol, so --trace-symbol was an exception.

This patch improves efficiency of the option by merging the
hash table into the symbol table.

Instead of looking up a separate hash table with a string,
this patch sets `Traced` flag to symbols specified by --trace-symbol.
So, if you insert a symbol and get a symbol with `Traced` flag on,
you know that you need to print out a log message for the symbol.
This is nearly zero cost.

llvm-svn: 275716
2016-07-17 17:50:09 +00:00
Rui Ueyama 2a7c1c1507 Print out file names for common symbols for --trace-symbol.
Previously, there was no way to get a file name for a DefinedCommon
symbol. This patch adds it.

llvm-svn: 275712
2016-07-17 17:36:22 +00:00
Rui Ueyama 663b8c2769 Handle versioned symbols efficiently.
Versions can be assigned to symbols in two different ways.
One is the usual version scripts, and the other is special
symbol suffix '@'. If a symbol contains '@', the string after
that is considered to specify a version name.

Previously, we look for '@' for all symbols.

Anything that works on every symbol can be expensive because
the linker has to handle a lot of symbols. The search for '@'
was not an exception.

In this patch, I made two optimizations.

The first optimization is to handle '@' only when at least one
version is defined. If no versions are defined, no versions can
be assigned to any symbols, so it's waste of time to search for '@'.

The second optimization is to scan only suffixes of symbol names
instead of entire symbol names. Symbol names can be very long, but
symbol versions are usually short, so scanning entire symbol names
is waste of time, too.

There are some error cases which we no longer be able to detect
with this patch. I don't think it's a major drawback because they
are minor errors. Speed is more important.

This change improves LLD with debug info self-link time from
6.6993 seconds to 6.3426 seconds (or -5.3%).

Differential Revision: https://reviews.llvm.org/D22433

llvm-svn: 275711
2016-07-17 17:23:17 +00:00
Rui Ueyama 434b56179e Add a pointer to a source file to SymbolBody.
Previously, each subclass of SymbolBody had a pointer to a source
file from which it was created. So, there was no single way to get
a source file for a symbol. We had getSourceFile<ELFT>(), but the
function was a bit inconvenient as it's a template.

This patch makes SymbolBody have a pointer to a source file.
If a symbol is not created from a file, the pointer has a nullptr.

llvm-svn: 275701
2016-07-17 03:11:46 +00:00
Rui Ueyama 818bb2f8dc Remove redundant namespace specifiers.
llvm-svn: 275694
2016-07-16 18:55:47 +00:00
Rui Ueyama 962b277d2d Resurrect code that was lost in conflicting commits.
llvm-svn: 275693
2016-07-16 18:45:25 +00:00
George Rimar 50dcece2a0 Recommit r275257 "[ELF] - Implement extern "c++" version script tag"
BSD toolchain contains a bug:
https://sourceforge.net/p/elftoolchain/tickets/491/

In short demangler works differently, fix was to update the testcase.
It should fix the FreeBSD bot failture:
http://lab.llvm.org:8011/builders/lld-x86_64-freebsd/builds/19432/steps/test_lld/logs/stdio

Original commit message was:
[ELF] - Implement extern "c++" version script tag

Patch implements 'extern' version script tag.
Currently only values in quotes(") are supported.

Matching of externs is performed in the same pass as exact match of globals.

Differential revision: http://reviews.llvm.org/D21930

llvm-svn: 275682
2016-07-16 12:26:39 +00:00
Rui Ueyama af469d47e9 Rename SymbolVersions VersionDefinitions.
SymbolVersions sounds like it had versions for a symbol, so rename it.

llvm-svn: 275674
2016-07-16 04:09:27 +00:00
Rui Ueyama bc94dd9b28 Rename Version VersionDefinition.
The identifier `Version` was used too often in the code to handle
symbol versions. The struct that contains version definitions is
named `Version`. Local variables for version ID are named `Version`.
Local varaible for version string are named `Version`.

This patch give them different names.

llvm-svn: 275673
2016-07-16 04:02:00 +00:00
Rui Ueyama c9b4c073b2 Simplify. NFC.
llvm-svn: 275670
2016-07-16 03:12:16 +00:00
Rui Ueyama 2506866ff6 Simplify default symbol version management. NFC.
llvm-svn: 275669
2016-07-16 03:08:26 +00:00
George Rimar dd64bb38bd Reverted r275257 "[ELF] - Implement extern "c++" version script tag"
It broke build bots:
http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast/builds/8204
http://lab.llvm.org:8011/builders/lld-x86_64-freebsd/builds/19432

llvm-svn: 275258
2016-07-13 08:19:04 +00:00
George Rimar e05103ea11 [ELF] - Implement extern "c++" version script tag
Patch implements 'extern' version script tag.
Currently only values in quotes(") are supported.

Matching of externs is performed in the same pass as exact match of globals.

Differential revision: http://reviews.llvm.org/D21930

llvm-svn: 275257
2016-07-13 07:46:00 +00:00
George Rimar 7899d48dff [ELF] - Add Id field to Version struct.
That helps to avoid expressions like I + 2 in code
that assigns version number to symbols.

Change was suggested by Rui Ueyama.

Differential revision: http://reviews.llvm.org/D22086

llvm-svn: 275159
2016-07-12 07:44:40 +00:00
George Rimar c61bcd80af [ELF] - Do not error out when version declaration not found when building executable.
When building executable usually version script is absent.
Before this patch error was shown in the case when
symbol name contained version and there was no script to match it.
  Instead of error out patch allows
to create new version declaration in this case and use it.
gnu linkers do the same.

That is PR28359.

Differential revision: http://reviews.llvm.org/D21890

llvm-svn: 274828
2016-07-08 06:47:28 +00:00
Rui Ueyama f4d9338dfb Move demangle() from Symbols.cpp to Strings.cpp.
Symbols.cpp contains functions to handle ELF symbols.
demangle() function is essentially a function to work on a
string rather than on an ELF symbol. So Strings.cpp is a
better place to put that function.

This change also make demangle to demangle symbols unconditionally.
Previously, it demangled symbols only when Config->Demangle is true.

llvm-svn: 274804
2016-07-07 23:04:15 +00:00
George Rimar f73a25812f [ELF] - Fixed incorrect logic of version assignments when mixing wildcards with values matching.
Previously we had incorrect logic here. Imagine we would have the next script:

LIBSAMPLE_1.0
{
  global:
   a_2;
 local:
  *;
};

LIBSAMPLE_2.0
{
  global:
   a*;
};
According to previous logic it would assign version 1 to a_2 and then
would try to reassign it to version 2 because of applying wildcard a*.
And show a warning about that.

Generally Ian Lance Tailor wrote about next rules that should be applied:
(http://www.airs.com/blog/archives/300)

Here are the current rules for gold:

"If there is an exact match for the mangled name, we use it. If there is more than one exact match, we give a warning, and we use the first tag in the script which matches. If a symbol has an exact match as both global and local for the same version tag, we give an error.
Otherwise, we look for an extern C++ or an extern Java exact match. If we find an exact match, we use it. If there is more than one exact match, we give a warning, and we use the first tag in the script which matches. If a symbol has an exact match as both global and local for the same version tag, we give an error.
Otherwise, we look through the wildcard patterns, ignoring “*” patterns. We look through the version tags in reverse order. For each version tag, we look through the global patterns and then the local patterns. We use the first match we find (i.e., the last matching version tag in the file).
Otherwise, we use the “*” pattern if there is one. We give a warning if there are multiple “*” patterns."

Patch makes wildcard matching to be in revered order and to follow after the regular naming matching.

Differential revision: http://reviews.llvm.org/D21894

llvm-svn: 274739
2016-07-07 07:45:27 +00:00
George Rimar dbbf60e590 [ELF] - Check the input bitcode files for compatibility.
Previously BC files were not checked for the same platform etc,
That lead to confusing error "Invalid section header entry size (e_shentsize) in ELF header" when
mixing files for different architectures.

Patch fixes PR28324.

Differential revision: http://reviews.llvm.org/D21832

llvm-svn: 274113
2016-06-29 09:46:00 +00:00
George Rimar 9fc1d4ed75 [ELF] - Updated comments. NFC.
As was suggested by Rafael Espíndola.

llvm-svn: 274111
2016-06-29 08:36:36 +00:00
Rui Ueyama 93c9af425e Create Strings.cpp and move string manipulation functions to that file.
llvm-svn: 274109
2016-06-29 08:01:32 +00:00
Rui Ueyama 722830a51b Rename matchStr -> globMatch.
llvm-svn: 274103
2016-06-29 05:32:09 +00:00
Rui Ueyama 48e4251e1d Make SymbolTable::findAll to return only defined symbols.
We allowed the function to return a vector that contains nullptrs
which is weird. This change makes the function to return only
defined symbols.

Differential Revision: http://reviews.llvm.org/D21828

llvm-svn: 274099
2016-06-29 04:47:39 +00:00
Davide Italiano 8e1131dc46 [ELF] Support for wildcard in version scripts.
Example:

VERSION_1.0 {
  global: foo*;
  local: *; }

now correctly matches all the symbols which name starts with
`foo`.

Differential Revision:  http://reviews.llvm.org/D21732

llvm-svn: 274091
2016-06-29 02:46:51 +00:00
Rui Ueyama 5e64d3fb94 Refactor ELF type inference functions.
Previously, we initialized Config->EKind and Config->EMachine when
we instantiate ELF objects. That was not an ideal location to do that
because the logic was buried too deep inside a concrete logic.

This patch moves the code to the driver so that the initialization
becomes explicit.

Differential Revision: http://reviews.llvm.org/D21784

llvm-svn: 274089
2016-06-29 01:30:50 +00:00
George Rimar 4365158689 [ELF] - Implemented support of default/non-default symbols versions
t is possible to create new version of symbol instead of depricated one
using combination of version script and asm commands. For example:

__asm__(".symver b_1,b@LIBSAMPLE_1.0");
int b_1() { return 10; }
__asm__(".symver b_2,b@@LIBSAMPLE_2.0");
int b_2() { return 20; }

This code makes b_2() to be default implementation for b().
b_1() is used for compatibility with binaries compiled against
library of older version LIBSAMPLE_1.0.

This patch implements support for above functionality in lld.

Differential revision: http://reviews.llvm.org/D21681

llvm-svn: 274002
2016-06-28 08:21:10 +00:00
George Rimar 36b2c0a683 [ELF] - Implemented --no-undefined-version flag
Option checks for cases where a version script explicitly lists
a symbol, but the symbol is not defined and errors out such
cases if any.

Differential revision: http://reviews.llvm.org/D21745

llvm-svn: 273998
2016-06-28 08:07:26 +00:00
Davide Italiano 4fdc648592 [ELF] Warn for duplicate symbols in version scripts instead of erroring out.
Emitting an error in this case breaks real-world application (e.g. libreoffice).
See http://reviews.llvm.org/D21555 for context.

Differential Revision:  http://reviews.llvm.org/D21781

llvm-svn: 273989
2016-06-28 03:40:49 +00:00
Rui Ueyama d60dae8a6a Implement --trace-symbol=symbol option.
Patch by Shridhar Joshi.

This option provides names of all the link time modules which define and
reference symbols requested by user. This helps to speed up application
development by detecting references causing undefined symbols.
It also helps in detecting symbols being resolved to wrong (unintended)
definitions in case of applications containing multiple definitions for
same symbols with different types, bindings.

Implements PR28226.

llvm-svn: 273536
2016-06-23 07:00:17 +00:00
George Rimar 50b80359c0 [ELF] - Do not allow to mix global symbols versions.
For next version script:
VER1{
  global:
  a;
};

VER2{
  global:
  a;
};
gold would produce warning like:
"warning: using 'VER1' as version for 'a' which is also named in version 'VER2' in script."

Documentation also says we do not want this duplications (https://people.freebsd.org/~deischen/symver/library_versioning.txt):
"Note that you do not want to duplicate symbols in the map file. The .symver directives are all that is required to add compatibility
symbols into old versions."

This patch restricts such mixing and makes lld to produce error in this case.

Differential revision: http://reviews.llvm.org/D21555

llvm-svn: 273396
2016-06-22 09:10:38 +00:00
George Rimar d3566309eb [ELF] - Recommit r273143("[ELF] - Basic versioned symbols support implemented.")
With fix:
-soname flag was not set in testcase. Hash calculated for base def was different on local
and bot machines because filename fos used for calculating.

Initial commit message:
Patch implements basic support of versioned symbols.
There is no wildcards patterns matching except local: *;
There is no support for hierarchies.
There is no support for symbols overrides (@ vs @@ not handled).

This patch allows programs that using simple scripts to link and run.

Differential revision: http://reviews.llvm.org/D21018

llvm-svn: 273152
2016-06-20 11:55:12 +00:00
George Rimar d03f97211a Revert r273143 "[ELF] - Basic versioned symbols support implemented."
It broke buildbot:
http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast

llvm-svn: 273146
2016-06-20 10:29:53 +00:00
George Rimar c31fee2212 [ELF] - Basic versioned symbols support implemented.
Patch implements basic support of versioned symbols.
There is no wildcards patterns matching except local: *;
There is no support for hierarchies.
There is no support for symbols overrides (@ vs @@ not handled).

This patch allows programs that using simple scripts to link and run.

Differential revision: http://reviews.llvm.org/D21018

llvm-svn: 273143
2016-06-20 10:16:33 +00:00
Rafael Espindola f70fb04e4f Make local: optional.
Doing that in an anonymous version is a bit silly, but this opens the
way for supporting it in general.

Since we don't support actual versions, for now we just disable the
version script if we detect that it is missing a local.

llvm-svn: 273000
2016-06-17 13:38:09 +00:00
Rafael Espindola cc70da39ff Internalize symbols in comdats.
We were dropping the CanOmitFromDynSym bit when creating undefined
symbols because of comdat.

llvm-svn: 272812
2016-06-15 17:56:10 +00:00
Rafael Espindola 65c65ce897 Don't include --start-lib/--end-lib files twice.
This should never happen with correct programs, but it is trivial
write a testcase where lld would crash or report duplicated
symbols. We now behave like when an archive is used and include the
file only once.

llvm-svn: 272724
2016-06-14 21:56:36 +00:00
Rafael Espindola 07543a8c2d Use a reference instead of a pointer. NFC.
llvm-svn: 272719
2016-06-14 21:40:23 +00:00
Peter Collingbourne ca8c994818 ELF: Compute used bit for --as-needed during symbol resolution.
We can now use this to decide whether to emit a verneed during the final
pass over the symbols. We were previously wrongly creating a verneed entry
in the case where all references to a DSO's symbols were weak.

In a future change we may also want to use the used bit to control whether
shared symbols are preemptible and appear in the dynsym. This seems a little
tricky to do at the moment because isNeeded() is templated.

The only other functional change here is that we emit a DT_NEEDED for DSOs
whose symbols are all preempted by objects that appear later in the link. But
that doesn't seem too important to me.

Differential Revision: http://reviews.llvm.org/D21171

llvm-svn: 272282
2016-06-09 18:01:35 +00:00
Rafael Espindola 78db5a9dca Print member name in undefined symbol error.
llvm-svn: 268976
2016-05-09 21:40:06 +00:00
Peter Collingbourne f3a2b0e8f7 ELF: Fix regression in TLS attribute mismatch logic.
Introduce a special symbol type to indicate that we have not yet seen a type
for the symbol, so we should not report TLS mismatches for that symbol.

Differential Revision: http://reviews.llvm.org/D19836

llvm-svn: 268411
2016-05-03 18:03:47 +00:00
Peter Collingbourne c357278a38 ELF: Remove the function SymbolTable<ELFT>::findFile.
We already have the function SymbolBody::getSourceFile which does the same thing.

llvm-svn: 268353
2016-05-03 01:48:25 +00:00
Peter Collingbourne 6a4225962d ELF: Forbid all relative relocations to absolute symbols in PIC, except for weak undefined.
Weak undefined symbols resolve to the image base. This is a little strange,
but it allows us to link function calls to such symbols. Normally such a
call will be guarded with a comparison, which will load a zero from the GOT.

There's one example of such a function call in crti.o in Linux's CRT.

As part of this change, I also needed to make the synthetic start and end
symbols image base relative in the case where their sections were empty,
so that PC-relative references to those symbols would continue to work.

Differential Revision: http://reviews.llvm.org/D19844

llvm-svn: 268350
2016-05-03 01:21:08 +00:00
Rui Ueyama 6d0cd2b62b Teach Undefined symbols from which file they are created from.
This patch increases the size of Undefined by the size of a pointer,
but it wouldn't actually increase the size of memory that LLD uses
because we are not allocating the exact size but the size of the
largest SymbolBody.

llvm-svn: 268310
2016-05-02 21:30:42 +00:00
Peter Collingbourne 4f9527065c ELF: New symbol table design.
This patch implements a new design for the symbol table that stores
SymbolBodies within a memory region of the Symbol object. Symbols are mutated
by constructing SymbolBodies in place over existing SymbolBodies, rather
than by mutating pointers. As mentioned in the initial proposal [1], this
memory layout helps reduce the cache miss rate by improving memory locality.

Performance numbers:

           old(s) new(s)
Without debug info:
chrome      7.178  6.432 (-11.5%)
LLVMgold.so 0.505  0.502 (-0.5%)
clang       0.954  0.827 (-15.4%)
llvm-as     0.052  0.045 (-15.5%)
With debug info:
scylla      5.695  5.613 (-1.5%)
clang      14.396 14.143 (-1.8%)

Performance counter results show that the fewer required indirections is
indeed the cause of the improved performance. For example, when linking
chrome, stalled cycles decreases from 14,556,444,002 to 12,959,238,310, and
instructions per cycle increases from 0.78 to 0.83. We are also executing
many fewer instructions (15,516,401,933 down to 15,002,434,310), probably
because we spend less time allocating SymbolBodies.

The new mechanism by which symbols are added to the symbol table is by calling
add* functions on the SymbolTable.

In this patch, I handle local symbols by storing them inside "unparented"
SymbolBodies. This is suboptimal, but if we do want to try to avoid allocating
these SymbolBodies, we can probably do that separately.

I also removed a few members from the SymbolBody class that were only being
used to pass information from the input file to the symbol table.

This patch implements the new design for the ELF linker only. I intend to
prepare a similar patch for the COFF linker.

[1] http://lists.llvm.org/pipermail/llvm-dev/2016-April/098832.html

Differential Revision: http://reviews.llvm.org/D19752

llvm-svn: 268178
2016-05-01 04:55:03 +00:00
George Rimar 9fc5908674 [ELF] Fixed warning. NFC.
SymbolTable.cpp:298:36: warning: enumeral and non-enumeral type in conditional expression [-Wextra]
     Sym->Binding = New->isShared() ? STB_GLOBAL : New->Binding;
                                    ^

llvm-svn: 268040
2016-04-29 13:32:30 +00:00
Rui Ueyama 62ee16faa8 Remove Size from Undefined symbol.
There seems to be no reason to keep st_size of undefined symbols.
This patch removes the member for it. This patch will change outputs
in cases that undefined symbols are copied to output, but I think
this is unimportant.

Differential Revision: http://reviews.llvm.org/D19574

llvm-svn: 267826
2016-04-28 00:26:54 +00:00
Rui Ueyama 1b70d666ae Do not lookup the symbol table twice for each --wrap.
llvm-svn: 267822
2016-04-28 00:03:38 +00:00
Peter Collingbourne 60976ed7c0 ELF: Merge UndefinedBitcode and UndefinedElf. NFC.
Differential Revision: http://reviews.llvm.org/D19566

llvm-svn: 267640
2016-04-27 00:05:06 +00:00
Peter Collingbourne 892d498017 ELF: Re-implement -u directly and remove CanKeepUndefined flag.
The semantics of the -u flag are to load the lazy symbol named by the flag. We
were previously relying on this behavior falling out of symbol resolution
against a synthetic undefined symbol, but that didn't quite give us the
correct behavior, so we needed a flag to mark symbols created with -u so
we could treat them specially in the writer. However, it's simpler and less
error prone to implement the required behavior directly and remove the flag.

This fixes an issue where symbols loaded with -u would receive hidden
visibility even when the definition in an object file had wider visibility.

Differential Revision: http://reviews.llvm.org/D19560

llvm-svn: 267639
2016-04-27 00:05:03 +00:00
Rafael Espindola 9e32e4fe86 Store the binding in the Symbol.
This remove a fixme, cleans up the weak undef interaction with archives and
lets us keep weak undefs still weak if they resolve to shared.

llvm-svn: 267555
2016-04-26 13:50:46 +00:00
Rui Ueyama 209f6cb055 Add more comment.
llvm-svn: 267260
2016-04-23 01:10:13 +00:00
Rui Ueyama 4255475139 Add comments.
llvm-svn: 267259
2016-04-23 00:26:32 +00:00
Peter Collingbourne 66ac1d6152 ELF: Implement basic support for --version-script.
This patch only implements support for version scripts of the form:
  { [ global: symbol1; symbol2; [...]; symbolN; ] local: *; };
No wildcards are supported, other than for the local entry. Symbol versioning
is also not supported.

It works by introducing a new Symbol flag which tracks whether a symbol
appears in the global section of a version script.

This patch also simplifies the logic in SymbolBody::isPreemptible(), and
teaches it to handle the case where symbols with default visibility in DSOs
do not appear in the dynamic symbol table because of a version script.

Fixes PR27482.

Differential Revision: http://reviews.llvm.org/D19430

llvm-svn: 267208
2016-04-22 20:21:26 +00:00
Peter Collingbourne e8d466293a Update an out of date comment.
llvm-svn: 267200
2016-04-22 19:56:45 +00:00
Peter Collingbourne dadcc17ead ELF: Move Visibility, IsUsedInRegularObj and MustBeInDynSym flags to Symbol.
These are properties of a symbol name, rather than a particular instance
of a symbol in an object file. We can simplify the code by collecting these
properties in Symbol.

The MustBeInDynSym flag has been renamed ExportDynamic, as its semantics
have been changed to be the same as those of --dynamic-list and
--export-dynamic-symbol, which do not cause hidden symbols to be exported.

Differential Revision: http://reviews.llvm.org/D19400

llvm-svn: 267183
2016-04-22 18:42:48 +00:00
Davide Italiano bc176631cd [LTO] Implement parallel Codegen for LTO using splitCodeGen.
Parallelism level can be chosen using the new --lto-jobs=K option
where K is the number of threads used for CodeGen. It currently
defaults to 1.

llvm-svn: 266484
2016-04-15 22:38:10 +00:00
Rafael Espindola 7f0b727235 Specialize the symbol table data structure a bit.
We never need to iterate over the K,V pairs, so we can avoid copying the
key as MapVector does.

This is a small speedup on most benchmarks.

llvm-svn: 266364
2016-04-14 20:42:43 +00:00
Adhemerval Zanella 9df0720766 ELF: Implement --dynamic-list
This patch implements the --dynamic-list option, which adds a list of
global symbol that either should not be bounded by default definition
when creating shared libraries, or add in dynamic symbol table in the
case of creating executables.

The patch modifies the ScriptParserBase class to use a list of Token
instead of StringRef, which contains information if the token is a
quoted or unquoted strings. It is used to use a faster search for
exact match symbol name.

The input file follow a similar format of linker script with some
simplifications (it does not have scope or node names). It leads
to a simplified parser define in DynamicList.{cpp,h}.

Different from ld/gold neither glob pattern nor mangled names
(extern 'C++') are currently supported.

llvm-svn: 266227
2016-04-13 18:51:11 +00:00
George Rimar 2a78fceb2c [ELF] - Change -t implementation to print which archive members are used.
Previously each archive file was reported no matter were it's member used or not,
like:
lib/libLLVMSupport.a

Now lld prints line for each used internal file, like:
lib/libLLVMSupport.a(lib/Support/CMakeFiles/LLVMSupport.dir/StringSaver.cpp.o)
lib/libLLVMSupport.a(lib/Support/CMakeFiles/LLVMSupport.dir/Host.cpp.o)
lib/libLLVMSupport.a(lib/Support/CMakeFiles/LLVMSupport.dir/ConvertUTF.c.o)

That should be consistent with what gold do.

This fixes PR27243.

Differential revision: http://reviews.llvm.org/D19011

llvm-svn: 266220
2016-04-13 18:07:57 +00:00
Peter Collingbourne f6e9b4ec24 ELF: Use hidden visibility for all DefinedSynthetic symbols.
This simplifies the code by allowing us to remove the visibility argument
to functions that create synthetic symbols.

The only functional change is that the visibility of the MIPS "_gp" symbol
is now hidden. Because this symbol is defined in every executable or DSO, it
would be difficult to observe a visibility change here.

Differential Revision: http://reviews.llvm.org/D19033

llvm-svn: 266208
2016-04-13 16:57:28 +00:00
Rafael Espindola 8caf33c483 Cleanup the handling of MustBeInDynSym and IsUsedInRegularObj.
Now MustBeInDynSym is only true if the symbol really must be in the
dynamic symbol table.

IsUsedInRegularObj is only true if the symbol is used in a .o or -u. Not
a .so or a .bc.

A benefit is that this is now done almost entirilly during symbol
resolution. The only exception is copy relocations because of aliases.

This includes a small fix in that protected symbols in .so don't force
executable symbols to be exported.

This also opens the way for implementing internalize for -shared.

llvm-svn: 265826
2016-04-08 18:39:03 +00:00
Rui Ueyama f8baa66056 ELF: Implement --start-lib and --end-lib
start-lib and end-lib are options to link object files in the same
semantics as archive files. If an object is in start-lib and end-lib,
the object is linked only when the file is needed to resolve
undefined symbols. That means, if an object is in start-lib and end-lib,
it behaves as if it were in an archive file.

In this patch, I introduced a new notion, LazyObjectFile. That is
analogous to Archive file type, but that works for a single object
file instead of for an archive file.

http://reviews.llvm.org/D18814

llvm-svn: 265710
2016-04-07 19:24:51 +00:00
Rafael Espindola f47657301b Change the type hierarchy for undefined symbols.
We have to differentiate undefined symbols from bitcode and undefined
symbols from other sources.

Undefined symbols from bitcode should not inhibit the symbol being
internalized. Undefined symbols from other sources should.

llvm-svn: 265536
2016-04-06 13:22:41 +00:00