Commit Graph

594 Commits

Author SHA1 Message Date
Rafael Espindola 40358fb86f Pass a std::unique_ptr to IRMover::move.
It was already the one "destroying" the source module, now the API
reflects that.

llvm-svn: 260989
2016-02-16 18:50:12 +00:00
Rafael Espindola cbc31d699b Delete the deprecated LLVMLinkModules.
llvm-svn: 260683
2016-02-12 15:28:45 +00:00
Teresa Johnson 488a800a4c [ThinLTO] Move global processing from Linker to TransformUtils (NFC)
Summary:
As discussed on IRC, move the ThinLTOGlobalProcessing code out of
the linker, and into TransformUtils. The name of the class is changed
to FunctionImportGlobalProcessing.

Reviewers: joker.eph, rafael

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D17081

llvm-svn: 260395
2016-02-10 18:11:31 +00:00
Teresa Johnson d7e88e515c [ThinLTO] Remove imported available externally defs from comdats.
Summary:
Available externally definitions are considered declarations for the
linker and eventually dropped. As such they are not allowed to be
in comdats. Remove any such imported functions from comdats.

Reviewers: rafael

Subscribers: davidxl, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D16120

llvm-svn: 260122
2016-02-08 18:47:20 +00:00
Teresa Johnson beb43ba7e5 Improve efficiency of handling unmapped subprogram metadata
The stripNullSubprograms function is very inefficient because
it walks all subprograms in all compile units in the dest module
any time a new module is linked in. For LTO in particular this will
get increasingly expensive as more modules are linked.

This patch improves the efficiency in several ways. The first is that
no scanning is necessary when there were no unneeded subprograms
identified in the first place. The second is that only the newly-linked
module's compile unit metadata should be examined.

Fixes PR26346.

llvm-svn: 259049
2016-01-28 15:08:09 +00:00
Chris Bieneman e49730d4ba Remove autoconf support
Summary:
This patch is provided in preparation for removing autoconf on 1/26. The proposal to remove autoconf on 1/26 was discussed on the llvm-dev thread here: http://lists.llvm.org/pipermail/llvm-dev/2016-January/093875.html

"I felt a great disturbance in the [build system], as if millions of [makefiles] suddenly cried out in terror and were suddenly silenced. I fear something [amazing] has happened."
- Obi Wan Kenobi

Reviewers: chandlerc, grosbach, bob.wilson, tstellarAMD, echristo, whitequark

Subscribers: chfast, simoncook, emaste, jholewinski, tberghammer, jfb, danalbert, srhines, arsenm, dschuff, jyknight, dsanders, joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D16471

llvm-svn: 258861
2016-01-26 21:29:08 +00:00
Teresa Johnson 71d12d2a4e [ThinLTO] Find all needed metadata when linking metadata as postpass
For metadata postpass linking, after importing all functions, we need
to recursively walk through any nodes reached via imported functions to
locate needed subprogram metadata. Some might only be reached indirectly
via the variable list for an inlined function.

llvm-svn: 258728
2016-01-25 22:04:56 +00:00
Teresa Johnson f07db00a65 [ThinLTO] Handle DISubprogram reached indirectly from DIImportedEntity
Extend fix for PR26037 to identify DISubprogram reached from a
DIImportedEntity via a DILexicalBlock.

llvm-svn: 258722
2016-01-25 21:29:55 +00:00
Teresa Johnson 6cba37ce75 [ThinLTO] Do metadata linking during batch function importing
Summary:
Since we are currently not doing incremental importing there is
no need to link metadata as a postpass. The module linker will
only link in the imported subroutines due to the functionality
added by r256003.

(Note that the metadata postpass linking functionalitiy is still
used by llvm-link, and may be needed here in the future if a more
incremental strategy is adopted.)

Reviewers: joker.eph

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D16424

llvm-svn: 258458
2016-01-22 00:15:53 +00:00
Teresa Johnson f5aa64f25f Use early return to simplify code (NFC)
Follow on to r258405.

llvm-svn: 258407
2016-01-21 17:16:53 +00:00
Teresa Johnson 6f508afce1 [ThinLTO] Avoid unnecesary hash lookups during metadata linking (NFC)
Replace sequences of count() followed by operator[] with either
find() or insert(), depending on the context.

llvm-svn: 258405
2016-01-21 16:46:40 +00:00
Rafael Espindola 394524d940 Remove redundant argument.
It is already a member variable.

llvm-svn: 258369
2016-01-21 00:00:53 +00:00
Rafael Espindola 55a7ae5cc7 Simplify the logic. NFC.
Found while reviewing the change for PR26152.

llvm-svn: 258362
2016-01-20 22:38:23 +00:00
Evgeniy Stepanov 9fb70f53ce Fix PR26152.
Fix the condition for when the new global takes over the name of
the existing one to be the negation of the condition for the new
global to get internal linkage.

llvm-svn: 258355
2016-01-20 22:05:50 +00:00
Manuel Jacob 5f6eaac611 GlobalValue: use getValueType() instead of getType()->getPointerElementType().
Reviewers: mjacob

Subscribers: jholewinski, arsenm, dsanders, dblaikie

Patch by Eduard Burtescu.

Differential Revision: http://reviews.llvm.org/D16260

llvm-svn: 257999
2016-01-16 20:30:46 +00:00
Teresa Johnson 5fe40050bd [IRMover] Don't copy personality, etc unless creating def
Function::copyAttributesFrom will copy the personality function, prefix
data and prolog data from the source function to the new function, and
is invoked when the IRMover copies the function prototype. This puts a
reference to a constant in the source module on a function in the dest
module, which causes an error when deleting the source module after
importing, since the personality function in the source module still has
uses (this would presumably also be an issue for the prologue and prefix
data). Remove the copies added to the dest copy when creating the new
prototype, as they are mapped properly when/if we link the function body.

llvm-svn: 257420
2016-01-12 00:24:24 +00:00
Teresa Johnson 1b00f2d99a [ThinLTO] Use new in-place symbol changes for exporting module
Due to the new in-place ThinLTO symbol handling support added in
r257174, we now invoke renameModuleForThinLTO on the current
module from within the FunctionImport pass.

Additionally, renameModuleForThinLTO no longer needs to return the
Module as it is performing the renaming in place on the one provided.

This commit will be immediately preceeded by a companion clang patch to
remove its invocation of renameModuleForThinLTO.

llvm-svn: 257181
2016-01-08 17:06:29 +00:00
Teresa Johnson 4504c1bc80 [ThinLTO] Enable in-place symbol changes for exporting module
Summary:
Move ThinLTO global value processing functions out of ModuleLinker and
into a new ThinLTOGlobalProcessor class, which performs any necessary
linkage and naming changes on the given module in place.

As a result, renameModuleForThinLTO no longer needs to create a new
Module when performing any necessary local to global promotion on a
module that we are possibly exporting from during a ThinLTO backend
compilation.

During function importing the ThinLTO processing is still invoked from
the ModuleLinker (via the new class), as it needs to perform renaming and
linkage changes on the source module, e.g. in order to get the correct
renaming during local to global promotion.

Reviewers: joker.eph

Subscribers: davidxl, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D15696

llvm-svn: 257174
2016-01-08 15:00:00 +00:00
Ahmed Bougacha a7324a2823 [Linker] Also treat a DIImportedEntity scope DISubprogram as needed.
Follow-up to r257000: DIImportedEntity can reach a DISubprogram via
its entity, but also via its scope. Handle the latter case as well.

PR26037.

llvm-svn: 257019
2016-01-07 03:14:59 +00:00
Teresa Johnson b951558294 Always treat DISubprogram reached by DIImportedEntity as needed.
It is illegal to have a null entity in a DIImportedEntity, so
we must link in a DISubprogram metadata node referenced by one,
even if the associated function is not linked in or inlined anywhere.

Fixes PR26037.

llvm-svn: 257000
2016-01-07 00:06:27 +00:00
Teresa Johnson 96f7f81aa3 [ThinLTO] Rename variables used in metadata linking (NFC)
As suggested in review for r255909, rename MDMaterialized to AllowTemps,
and identify the name of the boolean flag being set in calls to
saveMetadataList.

llvm-svn: 256653
2015-12-30 21:13:55 +00:00
Teresa Johnson cc428573a2 Ensure MDNode used as key in metadata linking map cannot be RAUWed
As suggested in review for r255909, add a way to ensure that temporary
MD used as keys in the MetadataToID map during ThinLTO importing are not
RAUWed.

Add support for marking an MDNode as not replaceable. Clear the new
CanReplace flag when adding a temporary MD node to the MetadataToID map
and clear it when destroying the map.

llvm-svn: 256648
2015-12-30 19:32:24 +00:00
Teresa Johnson 61b406ec75 Rename MDValue* to Metadata* (NFC)
Renamed MDValue* to Metadata*, and MDValueToValIDMap to MetadataToIDs,
as per review for r255909.

llvm-svn: 256593
2015-12-29 23:00:22 +00:00
Teresa Johnson d213aa469e Handle empty Subprogram list when linking metadata.
Use an iterator that handles an empty subprogram list.

Fixes PR25915.

llvm-svn: 256224
2015-12-22 01:17:19 +00:00
Teresa Johnson 4f04d85fa6 [ThinLTO] Rename variable to reflect bulk importing change (NFC)
llvm-svn: 256171
2015-12-21 17:33:24 +00:00
Teresa Johnson 4034d55158 Remove unused functions from ModuleLinker (NFC)
Remove a couple ModuleLinker methods and a related static function that
are no longer used after the linker split.

llvm-svn: 256162
2015-12-21 15:49:59 +00:00
Rafael Espindola 18c63b0f18 Drop support for dematerializing.
It was only used on lib/Linker and the use was "dead" since it was used on a
function the IRMover had just moved.

llvm-svn: 256019
2015-12-18 19:57:26 +00:00
Teresa Johnson bef543635a Rename variables to reflect linker split (NFC)
Renamed variables to be more reflective of whether they are
an instance of Linker, IRLinker or ModuleLinker. Also fix a stale
comment.

llvm-svn: 256011
2015-12-18 19:28:59 +00:00
Teresa Johnson 0e7c82cb69 [ThinLTO/LTO] Don't link in unneeded metadata
Summary:
Third patch split out from http://reviews.llvm.org/D14752.

Only map in needed DISubroutine metadata (imported or otherwise linked
in functions and other DISubroutine referenced by inlined instructions).
This is supported for ThinLTO, LTO and llvm-link --only-needed, with
associated tests for each one.

Depends on D14838.

Reviewers: dexonsmith, joker.eph

Subscribers: davidxl, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D14843

llvm-svn: 256003
2015-12-18 17:51:37 +00:00
Teresa Johnson e5a6191732 [ThinLTO] Metadata linking for imported functions
Summary:
Second patch split out from http://reviews.llvm.org/D14752.

Maps metadata as a post-pass from each module when importing complete,
suturing up final metadata to the temporary metadata left on the
imported instructions.

This entails saving the mapping from bitcode value id to temporary
metadata in the importing pass, and from bitcode value id to final
metadata during the metadata linking postpass.

Depends on D14825.

Reviewers: dexonsmith, joker.eph

Subscribers: davidxl, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D14838

llvm-svn: 255909
2015-12-17 17:14:09 +00:00
Teresa Johnson 4a9bf5872c Mark a couple ModuleLinker member functions as const (NFC)
llvm-svn: 255903
2015-12-17 16:34:53 +00:00
Rafael Espindola 434e956181 Change linkInModule to take a std::unique_ptr.
Passing in a std::unique_ptr should help find errors when the module
is used after being linked into another module.

llvm-svn: 255842
2015-12-16 23:16:33 +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
Rafael Espindola a8547d35e9 Fix another case where the linkage was not set.
llvm-svn: 255272
2015-12-10 18:44:26 +00:00
Rafael Espindola f81c7b03a0 Avoid undefined behavior when vector is empty.
Found by ubsan.

llvm-svn: 255258
2015-12-10 16:35:06 +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
Rafael Espindola ed11bd286f Synchronize the logic for deciding to link a gv.
We were deciding to not link an available_externally gv over a
declaration, but then copying over the body anyway.

llvm-svn: 255169
2015-12-09 22:44:00 +00:00
Rafael Espindola d57f9f0c90 Move all private members together. NFC.
llvm-svn: 255021
2015-12-08 14:54:49 +00:00
Rafael Espindola c6c9735f83 Factor two calls to a common location.
llvm-svn: 254967
2015-12-07 23:32:39 +00:00
Rafael Espindola e811c7b5ad Simplify the error handling a bit. NFC.
llvm-svn: 254952
2015-12-07 21:28:22 +00:00
Rafael Espindola bd03c50336 Link declaration lazily.
We already linked available_externally and linkonce lazily, this just
adds declarations to the list.

llvm-svn: 254917
2015-12-07 16:31:41 +00:00
Rafael Espindola a1240d8cb3 Change how the linker handles the old llvm.global_ctors.
Now instead of changing it to the new format and then linking, it just
handles the old format while copying it over.

The main differences are:

* There is no rauw in the source module.
* An old format input is always upgraded.

The first item helps with having a sane API that passes in a GV list to
the linker.

The second one is a small step in deprecating the old format.

llvm-svn: 254907
2015-12-07 13:24:23 +00:00
Teresa Johnson bae7e75959 [ThinLTO] Helper for performing renaming/promotion on a module
Creates a module and performs necessary renaming/promotion of locals
that may be exported to another module.

Split out of D15024.

llvm-svn: 254802
2015-12-04 23:40:22 +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
Teresa Johnson 1e20a652ee [ThinLTO] Appending linkage fixes
Summary:
Fix import from module with appending var, which cannot be imported. The
first fix is to remove an overly-aggressive error check.

The second fix is to deal with restructuring introduced to the module
linker yesterday in r254418 (actually, this fix was included already
in r254559, just added some additional cleanup).

Test by Mehdi Amini.

Reviewers: joker.eph, rafael

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D15156

llvm-svn: 254624
2015-12-03 18:20:05 +00:00
Rafael Espindola 562908bbd0 Simplify ValueMap handling.
We now just return values and let ValueMap handle the map.

llvm-svn: 254615
2015-12-03 16:36:16 +00:00
Rafael Espindola 792b7958ff Don't pass member variables to member functions. NFC.
llvm-svn: 254610
2015-12-03 14:48:20 +00:00
Mehdi Amini 7471cf81b0 Adapt comment and rename variable in ModuleLinker to describe more accurately the actual use.
Thanks Sean Silva for the suggestion.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 254582
2015-12-03 02:37:30 +00:00
Mehdi Amini 9abe1089c7 Remove "ExportingModule" from ThinLTO Index (NFC)
There is no real reason the index has to have the concept of an
exporting Module. We should be able to have one single unique
instance of the Index, and it should be read-only after creation
for the whole ThinLTO processing.
The linker plugin should be able to process multiple modules (in
parallel or in sequence) with the same index.

The only reason the ExportingModule was present seems to be to
implement hasExportedFunctions() that is used by the Module linker
to decide what to do with the current Module.
For now I replaced it with a query to the map of Modules path to
see if this module was declared in the Index and consider that if
it is the case then it is probably exporting function.
On the long term the Linker interface needs to evolve and this
call should not be needed anymore.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 254581
2015-12-03 02:37:23 +00:00
Rafael Espindola 4b5ec26373 Switch the linker to having a whitelist of GVs.
This replaces DoNotLinkFromSource with ValuesToLink. It also moves the
computation of ValuesToLink earlier.

It is a bit simpler and an important step in slitting the linker into an
ir mover and a linker proper.

The test change is because we now avoid creating dead declarations.

llvm-svn: 254559
2015-12-02 22:59:04 +00:00