Commit Graph

287 Commits

Author SHA1 Message Date
Davide Italiano 72d0d89b59 [gold] Remove inconsistent llvm_unreachable().
Differential Revision:	 http://reviews.llvm.org/D16429

llvm-svn: 258561
2016-01-22 21:36:49 +00:00
Rafael Espindola 240529892b Disable use list order on the gold plugin.
It turns out that his is *really* slow. With this change the link of
clang with plugin-opt=emit-llvm goes from 41 to 26 seconds.

We can add an option to enable it again if needed.

llvm-svn: 256302
2015-12-22 23:45:49 +00:00
Teresa Johnson 031bed291e Use LLVM style variable name (NFC)
Fixes variable name from r255779.

llvm-svn: 255824
2015-12-16 21:37:48 +00:00
Teresa Johnson cb15b739ef Add RAII wrapper for gold plugin file management
Suggested in review of r255256.

llvm-svn: 255779
2015-12-16 16:34:06 +00:00
Rafael Espindola 9d2bfc4874 Use diagnostic handler in the LLVMContext
This patch converts code that has access to a LLVMContext to not take a
diagnostic handler.

This has a few advantages

* It is easier to use a consistent diagnostic handler in a single program.
* Less clutter since we are not passing a handler around.

It does make it a bit awkward to implement some C APIs that return a
diagnostic string. I will propose new versions of these APIs and
deprecate the current ones.

llvm-svn: 255571
2015-12-14 23:17:03 +00:00
Teresa Johnson 9d5b71b3d2 [ThinLTO] Release files in gold plugin during combined index (take 2)
Ensure we release the files even when they don't hold a function index
summary section, by restructuring the control flow a little bit.

llvm-svn: 255256
2015-12-10 16:11:23 +00:00
Rafael Espindola caabe22832 Slit lib/Linker in two.
A linker normally has two stages: symbol resolution and "moving stuff".

In lib/Linker there is the complication of lazy linking some globals,
but it was still far more mixed than it needed to.

This splits the linker into a lower level IRMover and the linker proper.
The IRMover just takes a list of globals to move and a callback that
lets the user control what is lazy linked.

The main motivation is that now tools/gold (and soon lld) can use their
own symbol resolution to instruct IRMover what to do.

llvm-svn: 255254
2015-12-10 14:19:35 +00:00
Teresa Johnson db51357c11 [ThinLTO] Release files read when creating combined index in gold plugin
This wasn't causing an issue since at HEAD we exit the linker completely
after creating the combined index.

llvm-svn: 255156
2015-12-09 21:11:42 +00:00
Teresa Johnson af9e93183d Delay context construction to when/if it is needed in gold plugin (NFC)
llvm-svn: 255146
2015-12-09 19:49:40 +00:00
Teresa Johnson b13dbd633a clang-format order of gold-plugin includes (NFC)
llvm-svn: 255144
2015-12-09 19:45:55 +00:00
Rafael Espindola f49a38fc08 Always pass a diagnostic handler to the linker.
Before this patch the diagnostic handler was optional. If it was not
passed, the one in the LLVMContext was used.

That is probably not a pattern we want to follow. If each area has an
optional callback, there is a sea of callbacks and it is hard to follow
which one is called.

Doing this also found cases where the callback is a nice addition, like
testing that no errors or warnings are reported.

The other option is to always use the diagnostic handler in the
LLVMContext. That has a few problems

* To implement the C API we would have to set the diag handler and then
  set it back to the original value.
* Code that creates the context might be far away from code that wants
  the diagnostics.

I do have a patch that implements the second option and will send that as
an RFC.

llvm-svn: 254777
2015-12-04 22:08:53 +00:00
Rafael Espindola 0e309fe860 Use references now that it is natural to do so.
The linker never takes ownership of a module or changes which module it
is refering to, making it natural to use references.

llvm-svn: 254449
2015-12-01 19:50:54 +00:00
Rafael Espindola 19b52383c5 Simplify the linking of recursive data.
Now the ValueMapper has two callbacks. The first one maps the
declaration. The ValueMapper records the mapping and then materializes
the body/initializer.

llvm-svn: 254209
2015-11-27 20:28:19 +00:00
Rafael Espindola bca90bf158 Don't create implicit comdats.
comdats are explicitly represented for some time now.

llvm-svn: 253924
2015-11-23 22:01:51 +00:00
Teresa Johnson 6290dbc0f7 [ThinLTO] Handle bitcode without function summary sections gracefully
Summary:
Several fixes to the handling of bitcode files without function summary
sections so that they are skipped during ThinLTO processing in llvm-lto
and the gold plugin when appropriate instead of aborting.

1 Don't assert when trying to add a FunctionInfo that doesn't have
  a summary attached.
2 Skip FunctionInfo structures that don't have attached function summary
  sections when trying to create the combined function summary.
3 In both llvm-lto and gold-plugin, check whether a bitcode file has
  a function summary section before trying to parse the index, and skip
  the bitcode file if it does not.
4 Fix hasFunctionSummaryInMemBuffer in BitcodeReader, which had a bug
  where we returned to early while looking for the summary section.

Also added llvm-lto and gold-plugin based tests for cases where we
don't have function summaries in the bitcode file. I verified that
either the first couple fixes described above are enough to avoid the
crashes, or fixes 1,3,4. But have combined them all here for added
robustness.

Reviewers: joker.eph

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D14903

llvm-svn: 253796
2015-11-21 21:55:48 +00:00
Mehdi Amini 0027c1d21b Remove unused function parameter (NFC)
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 253569
2015-11-19 15:42:34 +00:00
NAKAMURA Takumi b13e63ce08 gold-plugin.cpp: Fix diagnosticHandler corresponding to r253540.
llvm-svn: 253553
2015-11-19 10:43:44 +00:00
Teresa Johnson f72278f051 Clang format a few prior patches (NFC)
I had clang formatted my earlier patches using the wrong style.
Reformatted with the LLVM style.

llvm-svn: 251812
2015-11-02 18:02:11 +00:00
Manuel Klimek 100f40c0fd Make class final to pacify -Wnon-virtual-dtor.
llvm-svn: 250805
2015-10-20 08:21:01 +00:00
Teresa Johnson 3da931f87a Pass FunctionInfoIndex by reference to WriteFunctionSummaryToFile (NFC)
Implemented suggestion by dblakie in review for r250704.

llvm-svn: 250723
2015-10-19 19:06:06 +00:00
Teresa Johnson 8af8d4ed93 Convert gold-plugin unnecessary unique_ptr into local (NFC)
llvm-svn: 250704
2015-10-19 15:23:03 +00:00
Teresa Johnson 403a787e03 Support for function summary index bitcode sections and files.
Summary:
The bitcode format is described in this document:
  https://drive.google.com/file/d/0B036uwnWM6RWdnBLakxmeDdOeXc/view
For more info on ThinLTO see:
  https://sites.google.com/site/llvmthinlto

The first customer is ThinLTO, however the data structures are designed
and named more generally based on prior feedback. There are a few
comments regarding how certain interfaces are used by ThinLTO, and the
options added here to gold currently have ThinLTO-specific names as the
behavior they provoke is currently ThinLTO-specific.

This patch includes support for generating per-module function indexes,
the combined index file via the gold plugin, and several tests
(more are included with the associated clang patch D11908).

Reviewers: dexonsmith, davidxl, joker.eph

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13107

llvm-svn: 249270
2015-10-04 14:33:43 +00:00
Teresa Johnson 8c8fe5a015 Disable the second verification run when performing LTO through
gold in NDEBUG mode.
Follow on patch for r247729 - LTO: Disable extra verify runs in release
builds.

llvm-svn: 247824
2015-09-16 18:06:45 +00:00
Peter Collingbourne 87202a4aac gold-plugin: Implement parallel LTO code generation using llvm::splitCodeGen.
Parallelism can be enabled using a new plugin option, jobs=N, where N is
the number of code generation threads.

Differential Revision: http://reviews.llvm.org/D12308

llvm-svn: 246584
2015-09-01 20:40:22 +00:00
Nick Lewycky 7282dd774f Replace &vector[0] with vector.data() to avoid invalid dereference caught by debug STL. Also move a '*' for consistency and fix an 80-col violation.
llvm-svn: 244134
2015-08-05 21:16:02 +00:00
Chandler Carruth df47bb9a06 Update for r243115 which changed the DataLayout API on TargetMachine but
didn't update the gold-plugin.

llvm-svn: 243121
2015-07-24 17:23:09 +00:00
Rafael Espindola 92200d237a gold-plugin: save the .o when given -save-temps.
The plugin now save the bitcode before and after optimizations and the
.o that is passed to the linker.

llvm-svn: 239726
2015-06-15 13:36:27 +00:00
Duncan P. N. Exon Smith e406c84e30 Fix build error from r234957
llvm-svn: 234958
2015-04-15 00:13:51 +00:00
Duncan P. N. Exon Smith a052ed6381 uselistorder: Pull the bit through WriteToBitcodFile()
Change the callers of `WriteToBitcodeFile()` to pass `true` or
`shouldPreserveBitcodeUseListOrder()` explicitly.  I left the callers
that want to send `false` alone.

I'll keep pushing the bit higher until hopefully I can delete the global
`cl::opt` entirely.

llvm-svn: 234957
2015-04-15 00:10:50 +00:00
Rafael Espindola 5682ce2ceb Simplify use of formatted_raw_ostream.
formatted_raw_ostream is a wrapper over another stream to add column and line
number tracking.

It is used only for asm printing.

This patch moves the its creation down to where we know we are printing
assembly. This has the following advantages:

* Simpler lifetime management: std::unique_ptr
* We don't compute column and line number of object files :-)

llvm-svn: 234535
2015-04-09 21:06:08 +00:00
Rafael Espindola ee0dd4d289 This reverts commit r234460 and r234461.
Revert "Add classof implementations to the raw_ostream classes."
Revert "Use the cast machinery to remove dummy uses of formatted_raw_ostream."

The underlying issue can be fixed without classof.

llvm-svn: 234495
2015-04-09 15:54:59 +00:00
Rafael Espindola 132381f981 Use the cast machinery to remove dummy uses of formatted_raw_ostream.
If we know we are producing an object, we don't need to wrap the stream
in a formatted_raw_ostream anymore.

llvm-svn: 234461
2015-04-09 02:28:12 +00:00
Rafael Espindola 0d68b4c5ed Fix PR23045.
Keep a note in the materializer that we are stripping debug info so that
user doing a lazy read of the module don't hit outdated formats.

Thanks to Duncan for suggesting the fix.

llvm-svn: 233603
2015-03-30 21:36:43 +00:00
Rafael Espindola 2fcfb5e5c7 Work around pr23045 and make it easier to reproduce.
Dropping old debug format requires the entire module to be read upfront.

This was failing only with the gold plugin, but that is just because
llvm-link was not upgrading metadata.

The new testcase using llvm-link shows the problem.

llvm-svn: 233381
2015-03-27 15:55:06 +00:00
Peter Collingbourne 070843d60b libLTO, llvm-lto, gold: Introduce flag for controlling optimization level.
This change also introduces a link-time optimization level of 1. This
optimization level runs only the globaldce pass as well as cleanup passes for
passes that run at -O0, specifically simplifycfg which cleans up lowerbitsets.

http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20150316/266951.html

llvm-svn: 232769
2015-03-19 22:01:00 +00:00
Rafael Espindola cba833a09d Be lazy about loading metadata in IRObjectFile.
This speeds up llvm-ar building lib64/libclangSema.a with debug IR files
from 8.658015807 seconds to just 0.351036519 seconds :-)

llvm-svn: 232221
2015-03-13 21:54:20 +00:00
Rafael Espindola 265ffbeb0c Fix the build of the gold-plugin and examples.
llvm-svn: 231279
2015-03-04 19:15:29 +00:00
Rafael Espindola f3f185486c Bring r231132 back with a fix.
The issue was that we were always printing the remarks. Fix that and add a test
showing that it prints nothing if -pass-remarks is not given.

Original message:
Correctly handle -pass-remarks in the gold plugin.

llvm-svn: 231273
2015-03-04 18:51:45 +00:00
NAKAMURA Takumi 84a9697c17 Revert r231132, "Correctly handle -pass-remarks in the gold plugin.", for now, to suppress log floodng in LTO.
llvm-svn: 231253
2015-03-04 16:24:28 +00:00
Rafael Espindola 84483d247f Correctly handle -pass-remarks in the gold plugin.
llvm-svn: 231132
2015-03-03 21:11:13 +00:00
Rafael Espindola 503f883b95 Add r230655 back with a fix.
The issue is that now we have a diag handler during optimizations
and get forward every optimization remark, flooding stdout.

The same filtering should probably be done with or without a
custom handler, but for now just ignore remarks.

Original message:

gold-plugin: "Upgrade" debug info and handle its warnings.

The gold plugin never calls MaterializeModule, so any old debug info
was not deleted and could cause crashes.

Now that it is being "upgraded", the plugin also has to handle warnings
and create Modules with a nice id (it shows in the warning).

llvm-svn: 230991
2015-03-02 19:08:03 +00:00
NAKAMURA Takumi 0f480f5010 Revert r230655, "gold-plugin: "Upgrade" debug info and handle its warnings."
It emits *millions of warnings* during selfhosting LTO build, to choke the buildbot with gigbytes of log.

llvm-svn: 230885
2015-03-01 04:16:28 +00:00
Rafael Espindola 7360fb6206 gold-plugin: "Upgrade" debug info and handle its warnings.
The gold plugin never calls MaterializeModule, so any old debug info
was not deleted and could cause crashes.

Now that it is being "upgraded", the plugin also has to handle warnings
and create Modules with a nice id (it shows in the warning).

llvm-svn: 230655
2015-02-26 18:24:37 +00:00
Rafael Espindola 85d8509267 Set the datalayout in the gold plugin.
This fixes the gold tests after r230054.

llvm-svn: 230098
2015-02-21 00:13:15 +00:00
Chandler Carruth edd92948d1 [gold] Consolidate the gold plugin options and actually search for
a gold binary explicitly. Substitute this binary into the tests rather
than just directly executing the 'ld' binary.

This should allow folks to inject a cross compiling gold binary, or in
my case to use a gold binary built and installed somewhere other than
/usr/bin/ld. It should also allow the tests to find 'ld.gold' so that
things work even if gold isn't the default on the system.

I've only stubbed out support in the makefile to preserve the existing
behavior with none of the fancy logic. If someone else wants to add
logic here, they're welcome to do so.

llvm-svn: 229251
2015-02-14 09:43:57 +00:00
Chandler Carruth 5700b3798f [PM] Fix a compile error I introduced in r229094 and didn't notice
because I didn't have binutils set up properly to build the gold plugin.

Fixes PR22581 which was filed because this broke the build for folks
relying on the plugin. Very sorry! =]

I've gotten the plugin stuff building now as well so it shouldn't keep
happening.

llvm-svn: 229156
2015-02-13 21:10:58 +00:00
Chandler Carruth 30d69c2e36 [PM] Remove the old 'PassManager.h' header file at the top level of
LLVM's include tree and the use of using declarations to hide the
'legacy' namespace for the old pass manager.

This undoes the primary modules-hostile change I made to keep
out-of-tree targets building. I sent an email inquiring about whether
this would be reasonable to do at this phase and people seemed fine with
it, so making it a reality. This should allow us to start bootstrapping
with modules to a certain extent along with making it easier to mix and
match headers in general.

The updates to any code for users of LLVM are very mechanical. Switch
from including "llvm/PassManager.h" to "llvm/IR/LegacyPassManager.h".
Qualify the types which now produce compile errors with "legacy::". The
most common ones are "PassManager", "PassManagerBase", and
"FunctionPassManager".

llvm-svn: 229094
2015-02-13 10:01:29 +00:00
Michael Kuperstein a07d9b9a4b gold-plugin: delete the output file for OT_DISABLE
bfd creates the output file early, so calling exit(0) is not enough, the file needs to be explicitly deleted.

Patch by: H.J. Lu <hjl.tools@gmail.com>

llvm-svn: 228946
2015-02-12 18:21:50 +00:00
Jan Wen Voung c11b45a2ea Gold-plugin: Broaden scope of get/release_input_file to scope of Module.
Summary:
Move calls to get_input_file and release_input_file out of
getModuleForFile(). Otherwise release_input_file may end up
unmapping a view of the file while the view is still being
used by the Module (on 32-bit hosts).

Fix for PR22482.

Test Plan: Add test using --no-map-whole-files.

Reviewers: rafael, nlewycky

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D7539

llvm-svn: 228842
2015-02-11 16:12:50 +00:00
NAKAMURA Takumi b0a52838fa gold-plugin.cpp: Fixup r227599 corresponding to r227685 and r227731 -- Don't lose DataLayoutPass.
llvm-svn: 227783
2015-02-02 05:47:30 +00:00
Alexey Samsonov 5ce244889c Fixup gold-plugin after r227576.
llvm-svn: 227599
2015-01-30 19:14:04 +00:00
Sylvestre Ledru 450f97dcb9 Update of the gold-plugin.cpp code to match Chandler's changes (r226981)
llvm-svn: 227004
2015-01-24 13:59:08 +00:00
Chandler Carruth 62d4215baa [PM] Move TargetLibraryInfo into the Analysis library.
While the term "Target" is in the name, it doesn't really have to do
with the LLVM Target library -- this isn't an abstraction which LLVM
targets generally need to implement or extend. It has much more to do
with modeling the various runtime libraries on different OSes and with
different runtime environments. The "target" in this sense is the more
general sense of a target of cross compilation.

This is in preparation for porting this analysis to the new pass
manager.

No functionality changed, and updates inbound for Clang and Polly.

llvm-svn: 226078
2015-01-15 02:16:27 +00:00
Rafael Espindola 9e3e53f6dd Fix linking of shared libraries.
In shared libraries the plugin can see non-weak declarations that are still
undefined.

llvm-svn: 226031
2015-01-14 20:08:46 +00:00
Rafael Espindola 0fd9e5f719 Fix handling of extern_weak. This was broken by r225983.
llvm-svn: 226026
2015-01-14 19:43:32 +00:00
Rafael Espindola 5ca7fa15fd Handle a symbol being undefined.
This can happen if:
* It is present in a comdat in one file.
* It is not present in the comdat of the file that is kept.
* Is is not used.

This should fix the LTO boostrap.

Thanks to Takumi NAKAMURA for setting up the bot!

llvm-svn: 225983
2015-01-14 13:53:50 +00:00
Rafael Espindola d0b23bef6f Use the DiagnosticHandler to print diagnostics when reading bitcode.
The bitcode reading interface used std::error_code to report an error to the
callers and it is the callers job to print diagnostics.

This is not ideal for error handling or diagnostic reporting:

* For error handling, all that the callers care about is 3 possibilities:
  * It worked
  * The bitcode file is corrupted/invalid.
  * The file is not bitcode at all.

* For diagnostic, it is user friendly to include far more information
  about the invalid case so the user can find out what is wrong with the
  bitcode file. This comes up, for example, when a developer introduces a
  bug while extending the format.

The compromise we had was to have a lot of error codes.

With this patch we use the DiagnosticHandler to communicate with the
human and std::error_code to communicate with the caller.

This allows us to have far fewer error codes and adds the infrastructure to
print better diagnostics. This is so because the diagnostics are printed when
he issue is found. The code that detected the problem in alive in the stack and
can pass down as much context as needed. As an example the patch updates
test/Bitcode/invalid.ll.

Using a DiagnosticHandler also moves the fatal/non-fatal error decision to the
caller. A simple one like llvm-dis can just use fatal errors. The gold plugin
needs a bit more complex treatment because of being passed non-bitcode files. An
hypothetical interactive tool would make all bitcode errors non-fatal.

llvm-svn: 225562
2015-01-10 00:07:30 +00:00
Rafael Espindola 538c9a88d9 Fix a leak found by asan.
llvm-svn: 224776
2014-12-23 18:18:37 +00:00
Rafael Espindola 4d47f7f52b Simplify the handling of aliases in the gold plugin.
The complicated situation is when we have to keep an alias but drop a GV
that is part of the aliasee.

We used to clone the dropped GV and make the clone internal. This is wasteful
as we know the original will be dropped.

With this patch what is done instead is set the linkage of the original to
internal and replace all uses (but the one in the alias) with a new
declaration that takes the name of the old GV. This saves us from having
to copy the body.

llvm-svn: 223863
2014-12-10 00:09:35 +00:00
Rafael Espindola 5dec7eaae2 Rename createIRObjectFile to just create.
It is a static method of IRObjectFile, so having to use
IRObjectFile::createIRObjectFile was redundant.

llvm-svn: 223822
2014-12-09 20:36:13 +00:00
Rafael Espindola a4f104b2ce Remember the unmangled name in the plugin.
This allows it to work with non trivial manglings like the one in COFF.

Amusingly, this can be tested with gold, as emit-llvm causes the plugin to
exit before any COFF is generated.

llvm-svn: 223790
2014-12-09 16:50:57 +00:00
Rafael Espindola 527e846ef7 Don't lookup an object symbol name in the module.
Instead, walk the obj symbol list in parallel to find the GV. This shouldn't
change anything on ELF where global symbols are not mangled, but it is a step
toward supporting other object formats.

Gold itself is ELF only, but bfd ld supports COFF and the logic in the gold
plugin could be reused on lld.

llvm-svn: 223780
2014-12-09 16:13:59 +00:00
Rafael Espindola 9c8ebeb03d Be less conservative about when we build the gold plugin.
It is only build if LLVM_BINUTILS_INCDIR is explicitly given, so there is
no point in having extra restrictions.

llvm-svn: 223481
2014-12-05 17:25:52 +00:00
Rafael Espindola 947bdb69cb gold plugin: call llvm_shutdown so that -stats works.
llvm-svn: 222787
2014-11-25 20:52:49 +00:00
Rafael Espindola 6953a3a6e0 Add a disable-output option to the gold plugin.
This corresponds to the opt option and is handy for profiling.

llvm-svn: 222687
2014-11-24 21:18:14 +00:00
Duncan P. N. Exon Smith f6ab47038c gold-plugin: Fix typo in error message
Spotted while reading code.

llvm-svn: 222395
2014-11-19 22:39:21 +00:00
Rafael Espindola b14407a300 Fix the build of the gold plugin.
I did the previous patch on OS X and didn't noticed the issue.

llvm-svn: 221070
2014-11-01 23:49:44 +00:00
Rafael Espindola 246c4fb5d9 Remove redundant calls to isMaterializable.
This removes calls to isMaterializable in the following cases:

* It was redundant with a call to isDeclaration now that isDeclaration returns
  the correct answer for materializable functions.
* It was followed by a call to Materialize. Just call Materialize and check EC.

llvm-svn: 221050
2014-11-01 16:46:18 +00:00
Rafael Espindola 919fb535a0 Enable the slp vectorizer in the gold plugin.
llvm-svn: 220887
2014-10-30 00:38:54 +00:00
Rafael Espindola 8391dbd1c6 Enable the loop vectorizer in the gold plugin.
llvm-svn: 220886
2014-10-30 00:11:24 +00:00
Rafael Espindola 4a3b6cf3c1 Replace also-emit-llvm with save-temps.
The also-emit-llvm option only supported getting the IR before optimizations.
This patch replaces it with a more generic save-temps option that saves the IR
both before and after optimizations.

llvm-svn: 220885
2014-10-29 23:54:45 +00:00
Rafael Espindola 8f2d615252 Remove unused variable.
llvm-svn: 220610
2014-10-25 04:07:53 +00:00
Rafael Espindola d12b4a334b Update the error handling of lib/Linker.
Instead of passing a std::string&, use the new diagnostic infrastructure.

llvm-svn: 220608
2014-10-25 04:06:10 +00:00
Rafael Espindola 5a52e6dc9e Modernize the error handling of the Materialize function.
llvm-svn: 220600
2014-10-24 22:50:48 +00:00
Rafael Espindola d4bcefc7d9 Don't ever call materializeAllPermanently during LTO.
To do this, change the representation of lazy loaded functions.

The previous representation cannot differentiate between a function whose body
has been removed and one whose body hasn't been read from the .bc file. That
means that in order to drop a function, the entire body had to be read.

llvm-svn: 220580
2014-10-24 18:13:04 +00:00
Rafael Espindola b0fc4cf3b9 Fix a gcc warning.
Thanks to Filipe Cabecinhas for the report.

llvm-svn: 220361
2014-10-22 02:23:31 +00:00
Rafael Espindola 2754dbb4ab Fix gcc warning in gold-plugin.cpp.
Patch by Markus Trippelsdorf!

llvm-svn: 219459
2014-10-10 00:48:13 +00:00
Rafael Espindola dfc7ed7ad0 gold plugin: Handle gold selecting a linkonce GV when a weak is present.
The plugin API doesn't have the notion of linkonce, only weak. It is up to the
plugin to figure out if a symbol used only for the symbol table can be dropped.
In particular, it has to avoid dropping a linkonce_odr selected by gold if there
is also a weak_odr.

llvm-svn: 219188
2014-10-07 04:06:13 +00:00
Rafael Espindola cb69583c50 gold plugin: create internal replacement with original linkage first.
The call to copyAttributesFrom will copy the visibility, which might assert
if it were to produce something invalid like "internal hidden". We avoid it
by first creating the replacement with the original linkage and then setting
it to internal affter the call to copyAttributesFrom.

llvm-svn: 219184
2014-10-07 03:19:55 +00:00
Rafael Espindola 93aec71ba9 gold plugin: Remap function arguments when creating a replacement function.
When creating an internal function replacement for use in an alias we were
not remapping the argument uses in the instructions to point to the new
arguments.

llvm-svn: 219177
2014-10-07 00:47:38 +00:00
Peter Collingbourne 10039c02ea LTO: introduce object file-based on-disk module format.
This format is simply a regular object file with the bitcode stored in a
section named ".llvmbc", plus any number of other (non-allocated) sections.

One immediate use case for this is to accommodate compilation processes
which expect the object file to contain metadata in non-allocated sections,
such as the ".go_export" section used by some Go compilers [1], although I
imagine that in the future we could consider compiling parts of the module
(such as large non-inlinable functions) directly into the object file to
improve LTO efficiency.

[1] http://golang.org/doc/install/gccgo#Imports

Differential Revision: http://reviews.llvm.org/D4371

llvm-svn: 218078
2014-09-18 21:28:49 +00:00
Rafael Espindola 51bd8ee309 Internalize common symbols when we can.
This fixes pr20974.

llvm-svn: 217981
2014-09-17 20:41:13 +00:00
Rafael Espindola c435adcde0 Add doInitialization/doFinalization to DataLayoutPass.
With this a DataLayoutPass can be reused for multiple modules.

Once we have doInitialization/doFinalization, it doesn't seem necessary to pass
a Module to the constructor.

Overall this change seems in line with the idea of making DataLayout a required
part of Module. With it the only way of having a DataLayout used is to add it
to the Module.

llvm-svn: 217548
2014-09-10 21:27:43 +00:00
Rafael Espindola 71143ed24b Remember to eraseFromParent after replaceAllUsesWith.
llvm-svn: 217536
2014-09-10 19:39:41 +00:00
Rafael Espindola 890db27b67 Handle common linkage correctly in the gold plugin.
This is the plugin version of pr20882.

This handles the case of every common symbol being in the IR. We will need some
support from gold to handle the case where some symbols are in ELF and some in
the IR.

llvm-svn: 217458
2014-09-09 20:08:22 +00:00
David Blaikie 10a27df8ff unique_ptrify IRObjectFile::createIRObjectFile
I took a guess at the changes to the gold plugin, because that doesn't
seem to build by default for me. Not sure what dependencies I might be
missing for that.

llvm-svn: 217056
2014-09-03 17:59:23 +00:00
Rafael Espindola 688121571a Pass a && to getLazyBitcodeModule.
This forces callers to use std::move when calling it. It is somewhat odd to have
code with std::move that doesn't always move, but it is also odd to have code
without std::move that sometimes moves.

llvm-svn: 217049
2014-09-03 17:31:46 +00:00
Rafael Espindola eeec8e63c0 Don't create a MemoryBuffer just to get the MemoryBufferRef. NFC.
llvm-svn: 216608
2014-08-27 20:25:55 +00:00
David Blaikie dfbe3d6b17 Convert a few more cases of direct intialization of unique_ptrs from MemoryBuffer::getMemBuffer to move initialization now that it returns by unique_ptr instead of raw pointer.
Cleanup/improvements following r216583.

llvm-svn: 216605
2014-08-27 20:14:18 +00:00
Rafael Espindola 3560ff2c1f Return a std::unique_ptr when creating a new MemoryBuffer.
llvm-svn: 216583
2014-08-27 20:03:13 +00:00
Rafael Espindola e2c1d77fb4 Pass a std::unique_ptr<MemoryBuffer>& to getLazyBitcodeModule.
By taking a reference we can do the ownership transfer in one place instead of
expecting every caller to do it.

llvm-svn: 216492
2014-08-26 22:00:09 +00:00
Rafael Espindola 3fd1e9933f Modernize raw_fd_ostream's constructor a bit.
Take a StringRef instead of a "const char *".
Take a "std::error_code &" instead of a "std::string &" for error.

A create static method would be even better, but this patch is already a bit too
big.

llvm-svn: 216393
2014-08-25 18:16:47 +00:00
Rafael Espindola f7ecb11572 Add support for comdats to the gold plugin.
There are two parts to this. First, the plugin needs to tell gold the comdat by
setting comdat_key.

What gets things a bit more complicated is that gold only seems
symbols. In particular, if A is an alias to B, it only sees the symbols
A and B. It can then ask us to keep symbol A but drop symbol B. What
we have to do instead is to create an internal version of B and make A
an alias to that.

At some point some of this logic should be moved to lib/Linker so that
we don't map a Constant to an internal version just to have lib/Linker
map that again to the destination module.

The reason for implementing this in tools/gold for now is simplicity.
With it in place it should be possible to update clang to use comdats
for constructors and destructors on ELF without breaking the LTO
bootstrap. Once that is done I intend to come back and improve the
interface lib/Linker exposes.

llvm-svn: 216302
2014-08-22 23:26:10 +00:00
Rafael Espindola 33466a745e Rewrite the gold plugin to fix pr19901.
There is a fundamental difference between how the gold API and lib/LTO view
the LTO process.

The gold API talks about a particular symbol in a particular file. The lib/LTO
API talks about a symbol in the merged module.

The merged module is then defined in terms of the IR semantics. In particular,
a linkonce_odr GV is only copied if it is used, since it is valid to drop
unused linkonce_odr GVs.

In the testcase in pr19901 both properties collide. What happens is that gold
asks us to keep a particular linkonce_odr symbol, but the IR linker doesn't
copy it to the merged module and we never have a chance to ask lib/LTO to keep
it.

This patch fixes it by having a more direct implementation of the gold API. If
it asks us to keep a symbol, we change the linkage so it is not linkonce. If it
says we can drop a symbol, we do so. All of this before we even send the module
to lib/Linker.

Since now we don't have to produce LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN,
during symbol resolution we can use a temporary LLVMContext and do lazy
module loading. This allows us to keep the minimum possible amount of
allocated memory around. This should also allow as much parallelism as
we want, since there is no shared context.

llvm-svn: 216215
2014-08-21 20:28:55 +00:00
Rafael Espindola 55b3254ea2 Fix using -plugin-opt=apiflie when also using -plugin-opt=emit-llvm.
llvm-svn: 215378
2014-08-11 19:06:54 +00:00
Rafael Espindola 0c54419d5d Remove unused argument.
Thanks to Justin Bogner for noticing it.

llvm-svn: 214426
2014-07-31 19:32:04 +00:00
Rafael Espindola d2aac5795e Use range loops.
llvm-svn: 214280
2014-07-30 01:52:40 +00:00
Rafael Espindola 54f82b72cc Convert a few more function pointer calls to just "f()".
llvm-svn: 214276
2014-07-30 01:36:32 +00:00
Rafael Espindola b6393291b4 Don't duplicate the function name in a comment.
llvm-svn: 214272
2014-07-30 01:23:45 +00:00
Rafael Espindola 5ad21fa696 Use function pointers with just f(1,2) instead of (*f)(1,2).
llvm-svn: 214265
2014-07-30 00:38:58 +00:00