Commit Graph

686 Commits

Author SHA1 Message Date
Eugene Leviant bf46e7410c [ThinLTO] Internalize readonly globals
An attempt to recommit r346584 after failure on OSX build bot.
Fixed cache key computation in ThinLTOCodeGenerator and added
test case

llvm-svn: 347033
2018-11-16 07:08:00 +00:00
Steven Wu fa43892d6f Revert "[ThinLTO] Internalize readonly globals"
This reverts commit 10c84a8f35cae4a9fc421648d9608fccda3925f2.

llvm-svn: 346768
2018-11-13 17:35:04 +00:00
Eugene Leviant be8d19967a [ThinLTO] Internalize readonly globals
This patch allows internalising globals if all accesses to them
(from live functions) are from non-volatile load instructions

Differential revision: https://reviews.llvm.org/D49362

llvm-svn: 346584
2018-11-10 08:31:21 +00:00
David Blaikie 40a64c4c08 llvm-link: Improve diagnostic for module-level metadata mismatch
This might produce hard to read/illegible diagnostics for especially
weird/non-trivial module metadata but integers are about all we are
using these days, so seems more useful than not.

Patch based on work by Kristina Brooks - thanks!

Differential Revision: https://reviews.llvm.org/D52952

llvm-svn: 344011
2018-10-09 01:17:27 +00:00
Matt Arsenault 9a71e80645 Fix asserts when linking wrong address space declarations
llvm-svn: 342858
2018-09-24 04:42:14 +00:00
Xin Tong bba2f473d4 [NFC] Remove an empty line.
llvm-svn: 338104
2018-07-27 06:50:45 +00:00
Eli Friedman 835297a951 [LTO] Fix linking with an alias defined using another alias.
When we're linking an alias which will be defined later, we neeed to
build a GlobalAlias, or else we'll crash later in
IRLinker::linkGlobalValueBody.

clang sometimes constructs aliases like this for C++ destructors.

Differential Revision: https://reviews.llvm.org/D49316

llvm-svn: 337053
2018-07-13 21:58:55 +00:00
Vlad Tsyrklevich 34b9112216 IRMover: Account for matching types present across modules
Summary:
Due to uniqueing of DICompositeTypes, it's possible for a type from one
module to be loaded into another earlier module without being renamed.
Then when the defining module is being IRMoved, the type can be used as
a Mapping destination before being loaded, such that when it's requested
using TypeMapTy::get() it will fail with an assertion that the type is a
source type when it's actually a type in both the source and
destination modules. Correctly handle that case by allowing a non-opaque
non-literal struct type be present in both modules.

Fix for PR37684.

Reviewers: pcc, tejohnson

Reviewed By: pcc, tejohnson

Subscribers: tobiasvk, mehdi_amini, steven_wu, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D47898

llvm-svn: 335145
2018-06-20 16:50:56 +00:00
Eugene Leviant 19e238746b [ThinLTO] Recommit of import global variables
This wasreverted in r326638 due to link problems and fixed
afterwards

llvm-svn: 327254
2018-03-12 10:30:50 +00:00
Chandler Carruth a4619d9944 [ThinLTO] Revert r325320: Import global variables
This caused some links to fail with ThinLTO due to missing symbols as
well as causing some binaries to have failures at runtime. We're working
with the author to get a test case, but want to get the tree green
again.

Further, it appears to introduce a data race. While the test usage of
threads was disabled in r325361 & r325362, that isn't an acceptable fix.
I've reverted both of these as well. This code needs to be thread safe.
Test cases for this are already on the original commit thread.

llvm-svn: 326638
2018-03-02 23:40:08 +00:00
Rafael Espindola 9a2bf413a0 Revert "[IRMover] Implement name based structure type mapping"
This reverts commit r325686.

There was a misunderstanding and this has not been approved yet.

llvm-svn: 325715
2018-02-21 20:12:18 +00:00
Eugene Leviant c556974f72 [IRMover] Implement name based structure type mapping
Differential revision: https://reviews.llvm.org/D43199

llvm-svn: 325686
2018-02-21 15:13:48 +00:00
Eugene Leviant 7331a0bf1c [ThinLTO] Import global variables
Differential revision: https://reviews.llvm.org/D43077

llvm-svn: 325320
2018-02-16 08:11:04 +00:00
Eugene Leviant 6a77bdb1eb [IRMover] Move type name extraction to a separate function. NFC
llvm-svn: 325110
2018-02-14 10:32:47 +00:00
Eugene Leviant 41e45955bb [IRMover] Add comment and fix test case
llvm-svn: 323407
2018-01-25 08:35:52 +00:00
Teresa Johnson ba22da0da3 Fix crash when linking metadata with ODR type uniquing
Summary:
With DebugTypeODRUniquing enabled, during IR linking debug metadata
in the destination module may be reached from the source module.
This means that ConstantAsMetadata nodes (e.g. on DITemplateValueParameter)
may contain a value the destination module. When trying to map such
metadata nodes, we will attempt to map a GV already in the dest module.
linkGlobalValueProto will end up with a source GV that is the same as
the dest GV as well as the new GV. Trying to access the TypeMap for the
source GV type, which is actually a dest GV type, hits an assertion
since it appears that we have mapped into the source module (because the
type is the value not a key into the map).

Detect that we don't need to access the TypeMap in this case, since
there is no need to create a bitcast from the new GV to the source GV
type as they GV are the same.

Fixes PR35722.

Reviewers: mehdi_amini, pcc

Subscribers: probinson, llvm-commits, eraman

Differential Revision: https://reviews.llvm.org/D41624

llvm-svn: 322103
2018-01-09 18:32:53 +00:00
Peter Collingbourne 00f808ffcc Linker: Create a function declaration when moving a non-prevailing alias of function type.
We were previously creating a global variable of function type,
which is invalid IR. This issue was exposed by r304690, in which we
started asserting that global variables were of a valid type.

Fixes PR33462.

Differential Revision: https://reviews.llvm.org/D36438

llvm-svn: 310543
2017-08-10 01:07:44 +00:00
Benoit Belley b1a9ad81c5 [Linker] PR33527 - Linker::LinkOnlyNeeded should import AppendingLinkage globals
Linker::LinkOnlyNeeded should always import globals with
AppendingLinkage.

This resolves PR33527.

Differential Revision: https://reviews.llvm.org/D34448

llvm-svn: 310522
2017-08-09 20:58:39 +00:00
Florian Hahn 745266b2a7 [Linker] Add directives to support mixing ARM/Thumb module-level inline asm.
Summary:
By prepending `.text .thumb .balign 2` to the module-level inline
assembly from a Thumb module, the assembler will generate the assembly
from that module as Thumb, even if the destination module uses an ARM
triple. Similar directives are used for module-level inline assembly in
ARM modules.

The alignment and instruction set are reset based on the target triple
before emitting the first function label.

Reviewers: olista01, tejohnson, echristo, t.p.northover, rafael

Reviewed By: echristo

Subscribers: aemerson, javed.absar, eraman, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D34622

llvm-svn: 307772
2017-07-12 11:52:28 +00:00
Teresa Johnson 2db1369c1f Support for taking the max of module flags when linking, use for PIE/PIC
Summary:
Add Max ModFlagBehavior, which can be used to take the max of two
module flag values when merging modules. Use it for the PIE and PIC
levels.

This avoids an error when we try to import from a module built -fpic
into a module built -fPIC, for example. For both PIE and PIC levels,
this will be legal, since the code generation gets more conservative
as the level is increased. Therefore we can take the max instead of
somehow trying to block importing between modules compiled with
different levels.

Reviewers: tmsriram, pcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33418

llvm-svn: 303590
2017-05-23 00:08:00 +00:00
Akira Hatanaka b10bff1183 [ThinLTO] Do not assert when adding a module with a different but
compatible target triple

Currently, an assertion fails in ThinLTOCodeGenerator::addModule when
the target triple of the module being added doesn't match that of the
one stored in TMBuilder. This patch relaxes the constraint and makes
changes to allow target triples that only differ in their version
numbers on Apple platforms, similarly to what r228999 did.

rdar://problem/30133904

Differential Revision: https://reviews.llvm.org/D33291

llvm-svn: 303326
2017-05-18 03:52:29 +00:00
Reid Kleckner e7c7854cb1 De-virtualize GlobalValue
The erase/remove from parent methods now use a switch table to remove
themselves from their appropriate parent ilist.

The copyAttributesFrom method is now completely non-virtual, since we
only ever copy attributes from a global of the appropriate type.

Pre-requisite to de-virtualizing Value to save a vptr
(https://reviews.llvm.org/D31261).

NFC

llvm-svn: 302823
2017-05-11 21:14:29 +00:00
Jonas Devlieghere 5eb9c81d82 [Linker] Provide callback for internalization
Differential Revision: https://reviews.llvm.org/D30738

llvm-svn: 297649
2017-03-13 18:08:11 +00:00
Peter Collingbourne e6fd9ff96a IRMover: Merge flags LinkModuleInlineAsm and IsPerformingImport.
Currently these flags are always the inverse of each other, so there is
no need to keep them separate.

Differential Revision: https://reviews.llvm.org/D29471

llvm-svn: 294016
2017-02-03 17:01:14 +00:00
Peter Collingbourne 7c70211653 ModuleLinker: Remove importing support. NFCI.
Differential Revision: https://reviews.llvm.org/D29470

llvm-svn: 294015
2017-02-03 16:58:19 +00:00
Peter Collingbourne 6d8f817f8b FunctionImport: Use IRMover directly.
The importer was previously using ModuleLinker in a sort of "IRMover mode". Use
IRMover directly instead in order to remove a level of indirection.

I will remove all importing support from ModuleLinker in a separate
change.

Differential Revision: https://reviews.llvm.org/D29468

llvm-svn: 294014
2017-02-03 16:56:27 +00:00
Peter Collingbourne c387e70c69 Linker: Move special casing for available_externally in IRMover to clients. NFCI.
The goal is to simplify the semantic model for clients of IRMover.

Differential Revision: https://reviews.llvm.org/D29435

llvm-svn: 293864
2017-02-02 05:12:15 +00:00
Teresa Johnson 040cc16835 [ThinLTO] Import only necessary DICompileUnit fields
Summary:
As discussed on mailing list, for ThinLTO importing we don't need
to import all the fields of the DICompileUnit. Don't import enums,
macros, retained types lists. Also only import local scoped imported
entities. Since we don't currently import any global variables,
we also don't need to import the list of global variables (added an
assert to verify none are being imported).

This is being done by pre-populating the value map entries to map
the unneeded metadata to nullptr. For the imported entities, we can
simply replace the source module's list with a new list containing
only those needed imported entities. This is done in the IRLinker
constructor so that value mapping automatically does the desired
mapping.

Reviewers: mehdi_amini, dexonsmith, dblaikie, aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D27635

llvm-svn: 289441
2016-12-12 16:09:30 +00:00
Peter Collingbourne bc0705240e IR: Move NumElements field from {Array,Vector}Type to SequentialType.
Now that PointerType is no longer a SequentialType, all SequentialTypes
have an associated number of elements, so we can move that information to
the base class, allowing for a number of simplifications.

Differential Revision: https://reviews.llvm.org/D27122

llvm-svn: 288464
2016-12-02 03:20:58 +00:00
Mehdi Amini fec2158292 [ThinLTO] Fix crash when importing an opaque type
It seems that because ThinLTO does not import the full module,
some invariant of the type mapper are broken.

In Monolithic LTO, we import every globals: when calling
IRLinker::copyFunctionProto() on @foo(), we end-up calling
TypeMapTy::get(FTy) on the type of @foo(), which will map
%0 and record the destination as opaque.

ThinLTO skips this because @foo is not imported and goes directly
to the next stage.

Next we call computeTypeMapping() that map the types for each
globals, and ends up checking for type isomorphism, and may add
type mapping. However it doesn't record if there was an opaque
destination type that was resolved.

Instead of lazily "discovering" opaque type in the destination
module on the go, we change the TypeFinder to eagerly record all
types and not only the named ones.

Differential Revision: https://reviews.llvm.org/D26840

llvm-svn: 287453
2016-11-19 18:44:16 +00:00
Hans Wennborg aeacdc258b IRMover: Avoid accidentally mapping types from the destination module (PR30799)
During Module linking, it's possible for SrcM->getIdentifiedStructTypes();
to return types that are actually defined in the destination module
(DstM). Depending on how the bitcode file was read,
getIdentifiedStructTypes() might do a walk over all values, including
metadata nodes, looking for types. In my case, a debug info metadata
node was shared between the two modules, and it referred to a type
defined in the destination module (see test case).

Differential Revision: https://reviews.llvm.org/D26212

llvm-svn: 287353
2016-11-18 17:33:05 +00:00
Peter Collingbourne 3cb86272fc Linker: Remove unnecessary call to copyMetadata in IRLinker::linkGlobalVariable.
This was causing us to create duplicate metadata on global variables.
Debug info test case by Adrian Prantl, additional test cases by me.

Fixes PR31012.

Differential Revision: https://reviews.llvm.org/D26622

llvm-svn: 286905
2016-11-14 23:18:38 +00:00
Adrian Prantl 1f9ac96cb1 Typo
llvm-svn: 286845
2016-11-14 17:26:32 +00:00
Peter Collingbourne 7f00d0a125 Bitcode: Change the materializer interface to return llvm::Error.
Differential Revision: https://reviews.llvm.org/D26439

llvm-svn: 286382
2016-11-09 17:49:19 +00:00
Hans Wennborg 2d55d67c62 Typo: nomed struct -> named struct
llvm-svn: 284635
2016-10-19 20:10:03 +00:00
Teresa Johnson 4b9b379172 [ThinLTO] Don't link module level assembly when importing
Module inline asm was always being linked/concatenated
when running the IRLinker. This is correct for full LTO but not when
we are importing for ThinLTO, as it can result in multiply defined
symbols when the module asm defines a global symbol.

In order to test with llvm-lto2, I had to work around PR30396,
where a symbol that is defined in module assembly but defined in the
LLVM IR appears twice. Added workaround to llvm-lto2 with a FIXME.

Fixes PR30610.

Reviewers: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D25359

llvm-svn: 284030
2016-10-12 18:39:29 +00:00
Peter Collingbourne d4135bbc30 DebugInfo: New metadata representation for global variables.
This patch reverses the edge from DIGlobalVariable to GlobalVariable.
This will allow us to more easily preserve debug info metadata when
manipulating global variables.

Fixes PR30362. A program for upgrading test cases is attached to that
bug.

Differential Revision: http://reviews.llvm.org/D20147

llvm-svn: 281284
2016-09-13 01:12:59 +00:00
Mehdi Amini ebb3434850 Fix ThinLTO crash with debug info
Because the recent change about ODR type uniquing in the context,
we can reach types defined in another module during IR linking.
This triggered some assertions in case we IR link without starting
from an empty module. To alleviate that, we can self-map metadata
defined in the destination module so that they won't be visited.

Differential Revision: https://reviews.llvm.org/D23841

llvm-svn: 280599
2016-09-03 21:12:33 +00:00
Justin Bogner 375f71e3a3 Linker: Avoid some ridiculous indentation by using a temporary. NFC
This was indented really awkwardly, and clang-format didn't seem to
know how to do any better. Avoid the issue with a temporary variable.

llvm-svn: 278756
2016-08-15 22:41:42 +00:00
David Majnemer c700490f48 Use the range variant of remove_if instead of unpacking begin/end
No functionality change is intended.

llvm-svn: 278475
2016-08-12 04:32:37 +00:00
Peter Collingbourne 7efd750607 IR: New representation for CFI and virtual call optimization pass metadata.
The bitset metadata currently used in LLVM has a few problems:

1. It has the wrong name. The name "bitset" refers to an implementation
   detail of one use of the metadata (i.e. its original use case, CFI).
   This makes it harder to understand, as the name makes no sense in the
   context of virtual call optimization.

2. It is represented using a global named metadata node, rather than
   being directly associated with a global. This makes it harder to
   manipulate the metadata when rebuilding global variables, summarise it
   as part of ThinLTO and drop unused metadata when associated globals are
   dropped. For this reason, CFI does not currently work correctly when
   both CFI and vcall opt are enabled, as vcall opt needs to rebuild vtable
   globals, and fails to associate metadata with the rebuilt globals. As I
   understand it, the same problem could also affect ASan, which rebuilds
   globals with a red zone.

This patch solves both of those problems in the following way:

1. Rename the metadata to "type metadata". This new name reflects how
   the metadata is currently being used (i.e. to represent type information
   for CFI and vtable opt). The new name is reflected in the name for the
   associated intrinsic (llvm.type.test) and pass (LowerTypeTests).

2. Attach metadata directly to the globals that it pertains to, rather
   than using the "llvm.bitsets" global metadata node as we are doing now.
   This is done using the newly introduced capability to attach
   metadata to global variables (r271348 and r271358).

See also: http://lists.llvm.org/pipermail/llvm-dev/2016-June/100462.html

Differential Revision: http://reviews.llvm.org/D21053

llvm-svn: 273729
2016-06-24 21:21:32 +00:00
Peter Collingbourne 4f7c16dd53 Linker: Copy metadata when linking declarations.
Differential Revision: http://reviews.llvm.org/D21624

llvm-svn: 273692
2016-06-24 17:42:21 +00:00
Artur Pilipenko 6c7a8abf5c Remangle intrinsics names when types are renamed
This is a resubmittion of previously reverted rL273568.

This is a fix for the problem mentioned in "LTO and intrinsics mangling" llvm-dev mail thread:
http://lists.llvm.org/pipermail/llvm-dev/2016-April/098387.html

Reviewers: mehdi_amini, reames

Differential Revision: http://reviews.llvm.org/D19373

llvm-svn: 273686
2016-06-24 15:10:29 +00:00
Hans Wennborg a63b50afb8 Revert r273568 "Remangle intrinsics names when types are renamed"
It broke 2008-07-15-Bswap.ll and 2009-09-01-PostRAProlog.ll

llvm-svn: 273574
2016-06-23 16:13:23 +00:00
Artur Pilipenko f0c9f81379 Remangle intrinsics names when types are renamed
This is a fix for the problem mentioned in "LTO and intrinsics mangling" llvm-dev mail thread:
http://lists.llvm.org/pipermail/llvm-dev/2016-April/098387.html

Reviewers: mehdi_amini, reames

Differential Revision: http://reviews.llvm.org/D19373

llvm-svn: 273568
2016-06-23 15:25:09 +00:00
Justin Lebar c05f3c9942 [IR] [DAE] Copy comdats during DAE, and don't copy comdats in GlobalObject::copyAttributesFrom.
Summary: This reverts the changes to Globals.cpp and IRMover.cpp in
"[IR] Copy comdats in GlobalObject::copyAttributesFrom" (D20631,
rL270743).

The DeadArgElim test is left unchanged, and we change DAE to explicitly
copy comdats.

The reverted change breaks copyAttributesFrom when the destination lives
in a different module from the source.  The decision in D21255 was to
revert this patch and handle comdat copying separately from
copyAttributesFrom.

Reviewers: majnemer, rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D21403

llvm-svn: 272855
2016-06-15 23:20:15 +00:00
Peter Collingbourne 96efdd6107 IR: Introduce local_unnamed_addr attribute.
If a local_unnamed_addr attribute is attached to a global, the address
is known to be insignificant within the module. It is distinct from the
existing unnamed_addr attribute in that it only describes a local property
of the module rather than a global property of the symbol.

This attribute is intended to be used by the code generator and LTO to allow
the linker to decide whether the global needs to be in the symbol table. It is
possible to exclude a global from the symbol table if three things are true:
- This attribute is present on every instance of the global (which means that
  the normal rule that the global must have a unique address can be broken without
  being observable by the program by performing comparisons against the global's
  address)
- The global has linkonce_odr linkage (which means that each linkage unit must have
  its own copy of the global if it requires one, and the copy in each linkage unit
  must be the same)
- It is a constant or a function (which means that the program cannot observe that
  the unique-address rule has been broken by writing to the global)

Although this attribute could in principle be computed from the module
contents, LTO clients (i.e. linkers) will normally need to be able to compute
this property as part of symbol resolution, and it would be inefficient to
materialize every module just to compute it.

See:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160509/356401.html
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160516/356738.html
for earlier discussion.

Part of the fix for PR27553.

Differential Revision: http://reviews.llvm.org/D20348

llvm-svn: 272709
2016-06-14 21:01:22 +00:00
Benjamin Kramer d3f4c05aea Move instances of std::function.
Or replace with llvm::function_ref if it's never stored. NFC intended.

llvm-svn: 272513
2016-06-12 16:13:55 +00:00
Benjamin Kramer c321e53402 Apply most suggestions of clang-tidy's performance-unnecessary-value-param
Avoids unnecessary copies. All changes audited & pass tests with asan.
No functional change intended.

llvm-svn: 272190
2016-06-08 19:09:22 +00:00
Davide Italiano 953396536b [Linker/IRMover] Simplify the code a bit. NFCI.
llvm-svn: 272013
2016-06-07 14:55:04 +00:00