119 Commits

Author SHA1 Message Date
Mehdi Amini
e4c5b69aa3 Add support for -fno-builtin to LTO and ThinLTO to libLTO
Reviewers: tejohnson, pcc

Subscribers: Prazek, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D30791

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298936 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28 18:55:44 +00:00
Teresa Johnson
08d0e94685 [ThinLTO] Add support for emitting minimized bitcode for thin link
Summary:
The cumulative size of the bitcode files for a very large application
can be huge, particularly with -g. In a distributed build environment,
all of these files must be sent to the remote build node that performs
the thin link step, and this can exceed size limits.

The thin link actually only needs the summary along with a bitcode
symbol table. Until we have a proper bitcode symbol table, simply
stripping the debug metadata results in significant size reduction.

Add support for an option to additionally emit minimized bitcode
modules, just for use in the thin link step, which for now just strips
all debug metadata. I plan to add a cc1 option so this can be invoked
easily during the compile step.

However, care must be taken to ensure that these minimized thin link
bitcode files produce the same index as with the original bitcode files,
as these original bitcode files will be used in the backends.

Specifically:
1) The module hash used for caching is typically produced by hashing the
written bitcode, and we want to include the hash that would correspond
to the original bitcode file. This is because we want to ensure that
changes in the stripped portions affect caching. Added plumbing to emit
the same module hash in the minimized thin link bitcode file.
2) The module paths in the index are constructed from the module ID of
each thin linked bitcode, and typically is automatically generated from
the input file path. This is the path used for finding the modules to
import from, and obviously we need this to point to the original bitcode
files. Added gold-plugin support to take a suffix replacement during the
thin link that is used to override the identifier on the MemoryBufferRef
constructed from the loaded thin link bitcode file. The assumption is
that the build system can specify that the minimized bitcode file has a
name that is similar but uses a different suffix (e.g. out.thinlink.bc
instead of out.o).

Added various tests to ensure that we get identical index files out of
the thin link step.

Reviewers: mehdi_amini, pcc

Subscribers: Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D31027

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298638 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-23 19:47:39 +00:00
Peter Collingbourne
22910652da Support, LTO: When pruning a directory, ignore files matching a prefix.
This is a safeguard against data loss if the user specifies a directory
that is not a cache directory. Teach the existing cache pruning clients
to create files with appropriate names.

Differential Revision: https://reviews.llvm.org/D31109

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298271 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-20 16:41:57 +00:00
Evgeniy Stepanov
df808fe215 Add !associated metadata.
This is an ELF-specific thing that adds SHF_LINK_ORDER to the global's section
pointing to the metadata argument's section. The effect of that is a reverse dependency
between sections for the linker GC.

!associated does not change the behavior of global-dce. The global
may also need to be added to llvm.compiler.used.

Since SHF_LINK_ORDER is per-section, !associated effectively enables
fdata-sections for the affected globals, the same as comdats do.

Differential Revision: https://reviews.llvm.org/D29104

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298157 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-17 22:17:24 +00:00
Peter Collingbourne
a58d2a9027 LTO: Hash type identifier resolutions for WholeProgramDevirt.
Differential Revision: https://reviews.llvm.org/D30555

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297514 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-10 21:37:10 +00:00
Peter Collingbourne
a354228e67 LTO: Hash type identifier resolutions for LowerTypeTests.
Differential Revision: https://reviews.llvm.org/D30553

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297513 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-10 21:35:17 +00:00
Peter Collingbourne
059abefa09 LTO: Hash the set of imported symbols for each module.
This set may affect code generation and is sensitive to link order (and
possibly in the future to the linker's choice of prevailing symbol), so we
need to include it.

Differential Revision: https://reviews.llvm.org/D30586

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296907 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-03 20:25:30 +00:00
Peter Collingbourne
cc5ba4427e LTO: When creating a local cache, create the cache directory if it does not already exist.
Differential Revision: https://reviews.llvm.org/D30519

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296726 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-02 02:02:38 +00:00
Justin Bogner
a39b1ce61f Verifier: Disallow a line number without a file in DISubprogram
A line number doesn't make much sense if you don't say where it's
from. Add a verifier check for this and update some tests that had
bogus debug info.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295516 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-17 23:57:42 +00:00
Davide Italiano
0d336bb01a [tests] Be explicit about the files we want to remove.
Hopefully Windows will stop whining after this change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294801 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-10 22:55:37 +00:00
Davide Italiano
a613077da7 [ThinLTO] Make this test more robust across multiple runs.
The yaml emitter files are left around otherwise.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294784 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-10 21:35:31 +00:00
Eric Christopher
8c54b816e5 Temporarily revert "For X86-64 linux and PPC64 linux align int128 to 16 bytes."
until we can get better TargetMachine::isCompatibleDataLayout to compare - otherwise
we can't code generate existing bitcode without a string equality data layout.

This reverts commit r294702.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294709 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-10 04:35:32 +00:00
Eric Christopher
d11a6cc2e7 For X86-64 linux and PPC64 linux align int128 to 16 bytes.
For other platforms we should find out what they need and likely
make the same change, however, a smaller additional change is easier
for platforms we know have it specified	in the ABI. As part of this
rewrite some of the handling in the backends for data layout and update
a bunch of testcases.

Based on a patch by Simonas Kazlauskas!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294702 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-10 03:32:21 +00:00
Mehdi Amini
38fd8b4c14 Revert "[ThinLTO] Add an auto-hide feature"
This reverts commit r293970.

After more discussion, this belongs to the linker side and
there is no added value to do it at this level.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293993 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-03 07:41:43 +00:00
Mehdi Amini
bd57345762 [ThinLTO] Add an auto-hide feature
When a symbol is not exported outside of the
DSO, it is can be hidden. Usually we try to internalize
as much as possible, but it is not always possible, for
instance a symbol can be referenced outside of the LTO
unit, or there can be cross-module reference in ThinLTO.

This is a recommit of r293912 after fixing build failures,
and a recommit of r293918 after fixing LLD tests.

Differential Revision: https://reviews.llvm.org/D28978

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293970 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-03 00:32:38 +00:00
Mehdi Amini
5674a467ef Revert "[ThinLTO] Add an auto-hide feature"
This reverts commit r293918, one lld test does not pass.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293961 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-02 23:20:36 +00:00
Mehdi Amini
20af8a7bb3 [ThinLTO] Add an auto-hide feature
When a symbol is not exported outside of the
DSO, it is can be hidden. Usually we try to internalize
as much as possible, but it is not always possible, for
instance a symbol can be referenced outside of the LTO
unit, or there can be cross-module reference in ThinLTO.

This is a recommit of r293912 after fixing build failures.

Differential Revision: https://reviews.llvm.org/D28978

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293918 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-02 18:31:35 +00:00
Mehdi Amini
416bf90086 Revert "[ThinLTO] Add an auto-hide feature"
This reverts r293912, bots are broken.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293914 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-02 18:24:37 +00:00
Mehdi Amini
73efdef798 [ThinLTO] Add an auto-hide feature
When a symbol is not exported outside of the
DSO, it is can be hidden. Usually we try to internalize
as much as possible, but it is not always possible, for
instance a symbol can be referenced outside of the LTO
unit, or there can be cross-module reference in ThinLTO.

Differential Revision: https://reviews.llvm.org/D28978

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293912 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-02 18:13:46 +00:00
Davide Italiano
71d2fd7c90 [LTO] Add test to show up we don't support ThinLTO yet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292865 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-24 00:59:00 +00:00
Teresa Johnson
1f32b341a8 [ThinLTO] Drop non-prevailing non-ODR weak to declarations
Summary:
Allow non-ODR weak/linkonce non-prevailing copies to be marked
as available_externally in the index. Add support for dropping these to
declarations in the backend.

Reviewers: mehdi_amini, pcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28806

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292656 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-20 21:54:58 +00:00
Mehdi Amini
85b2e0b34b [ThinLTO] Fix lazy-loading of MDString instruction attachments
CFI is using intrinsics that takes MDString as arguments, and this
was broken during lazy-loading of metadata.

Differential Revision: https://reviews.llvm.org/D28916

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292641 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-20 20:29:16 +00:00
Mehdi Amini
6449993f8f [ThinLTO] Add a recursive step in Metadata lazy-loading
Summary:
Without this, we're stressing the RAUW of unique nodes,
which is a costly operation. This is intended to limit
the number of RAUW, and is very effective on the total
link-time of opt with ThinLTO, before:

  real 4m4.587s  user 15m3.401s  sys 0m23.616s

after:

  real 3m25.261s user 12m22.132s sys 0m24.152s

Reviewers: tejohnson, pcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28751

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292420 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-18 18:36:21 +00:00
Teresa Johnson
801dc0146e [ThinLTO] Import static functions from the same module as caller
Summary:
We can sometimes end up with multiple copies of a local function that
have the same GUID in the index. This happens when there are local
functions with the same name that are in different source files with the
same name (but in different directories), and they were compiled in
their own directory so had the same path at compile time.

In this case make sure we import the copy in the caller's module. While
it isn't a correctness problem (the renamed reference which is based on the
module IR hash will be unique since the module must have had an
externally visible function that was imported), importing the wrong copy
will result in lost performance opportunity since it won't be referenced
and inlined.

Reviewers: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28440

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291841 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-12 22:04:45 +00:00
Mehdi Amini
fd47fbc5dc [ThinLTO] Fix assertions on lazy-loading of Metadata TBAA attachments
Summary:
The issue happens with:

 %0 = ....., !tbaa 
 %1 = ....., !tbaa 

With  that references .

In this case when loading  we generates a temporary for the
operand . We now flush it immediately and trigger the load of
 before moving on. If we don't we get the temporary when
attaching to %1. This is usually not an issue except that we
eagerly try to update TBAA MDNodes, which is obviously not possible
if we only have a temporary.

Differential Revision: https://reviews.llvm.org/D28423

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291362 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-07 20:24:23 +00:00
Teresa Johnson
17b59bf192 [ThinLTO] Handle conflicting local names gracefully
Summary:
r285871 introduced an assert that was overly aggressive in the case
of a same-named local in different same-named files (in different
directories), where the source name and therefore the GUID ended up
the same because the files were compiled in their own directory without
any leading path. Change the handling in the promotion logic to get
the summary for the version in that module.

This also exposed an issue where we are not always importing the
right copy, which is a performance not correctness issue (because
the renaming is based on the module hash which must be different,
see the bug report for details). I will fix that as a follow-on.

Fixes PR31561.

Reviewers: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28411

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291304 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-06 23:38:41 +00:00
Teresa Johnson
a4ca999339 ThinLTO: add early "dead-stripping" on the Index
Summary:
Using the linker-supplied list of "preserved" symbols, we can compute
the list of "dead" symbols, i.e. the one that are not reachable from
a "preserved" symbol transitively on the reference graph.
Right now we are using this information to mark these functions as
non-eligible for import.

The impact is two folds:
- Reduction of compile time: we don't import these functions anywhere
  or import the function these symbols are calling.
- The limited number of import/export leads to better internalization.

Patch originally by Mehdi Amini.

Reviewers: mehdi_amini, pcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D23488

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291177 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-05 21:34:18 +00:00
Mehdi Amini
d171b5cffe Mark test that is testing statistics output as requiring Assertions
We only enable statistic in an assert build by default.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291044 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-05 01:08:01 +00:00
Mehdi Amini
d240497d67 Use lazy-loading of Metadata in MetadataLoader when importing is enabled (NFC)
Summary:
This is a relatively simple scheme: we use the index emitted in the
bitcode to avoid loading all the global metadata. Instead we load
the index with their position in the bitcode so that we can load each
of them individually. Materializing the global metadata block in this
condition only triggers loading the named metadata, and the ones
referenced from there (transitively). When materializing a function,
metadata from the global block are loaded lazily as they are
referenced.

Two main current limitations are:

1) Global values other than functions are not materialized on demand,
so we need to eagerly load METADATA_GLOBAL_DECL_ATTACHMENT records
(and their transitive dependencies).
2) When we load a single metadata, we don't recurse on the operands,
instead we use a placeholder or a temporary metadata. Unfortunately
tepmorary nodes are very expensive. This is why we don't have it
always enabled and only for importing.

These two limitations can be lifted in a subsequent improvement if
needed.

With this change, the total link time of opt with ThinLTO and Debug
Info enabled is going down from 282s to 224s (~20%).

Reviewers: pcc, tejohnson, dexonsmith

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28113

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291027 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-04 22:54:33 +00:00
Teresa Johnson
621de7b4c7 [ThinLTO] Rework llvm-link to use the FunctionImporter
Summary:
Change llvm-link to use the FunctionImporter handling, instead of
manually invoking the Linker. We still need to load the module
in llvm-link to do the desired testing for invalid import requests
(weak functions), and to get the GUID (in case the function is local).

Also change the drop-debug-info test to use llvm-link so that importing
is forced (in order to test debug info handling) and independent of
import logic changes.

Reviewers: mehdi_amini

Subscribers: mgorny, llvm-commits, aprantl

Differential Revision: https://reviews.llvm.org/D28277

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290964 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-04 14:27:31 +00:00
Mehdi Amini
c075007a09 Fix test change in r290736: restore index generation
I remove one extra line, but because annoyingly llvm-lit does not
clean the output directory before running the test, it didn't fail
locally (the file was present from a previous run).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290740 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-30 01:15:50 +00:00
Mehdi Amini
07ddca829a Replace test from using llvm-lto to use llvm-link (NFC)
Some incoming changes in ThinLTO will break this test.
Instead of relying on the heuristic to import, we
force the importing to happen with llvm-link.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290736 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-30 00:45:26 +00:00
Teresa Johnson
21f0f3a5ef [ThinLTO] Fix "||" vs "|" mixup.
The effect of the bug was that we would incorrectly create summaries
for global and weak values defined in module asm (since we were
essentially testing for bit 1 which is SF_Undefined, and the
RecordStreamer ignores local undefined references). This would have
resulted in conservatively disabling importing of anything referencing
globals and weaks defined in module asm. Added these cases to the test
which now fails without this bug fix.

Fixes PR31459.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290610 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-27 17:45:09 +00:00
Adrian Prantl
c271bc0481 Renumber testcase metadata nodes after r290153.
This patch renumbers the metadata nodes in debug info testcases after
https://reviews.llvm.org/D26769. This is a separate patch because it
causes so much churn. This was implemented with a python script that
pipes the testcases through llvm-as - | llvm-dis - and then goes
through the original and new output side-by side to insert all
comments at a close-enough location.

Differential Revision: https://reviews.llvm.org/D27765

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290292 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-22 00:45:21 +00:00
Adrian Prantl
7b500b4bdf [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

This reapplies r289902 with additional testcase upgrades and a change
to the Bitcode record for DIGlobalVariable, that makes upgrading the
old format unambiguous also for variables without DIExpressions.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290153 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-20 02:09:43 +00:00
Teresa Johnson
f638013746 [ThinLTO] Import composite types as declarations
Summary:
When reading the metadata bitcode, create a type declaration when
possible for composite types when we are importing. Doing this in
the bitcode reader saves memory. Also it works naturally in the case
when the type ODR map contains a definition for the same composite type
because it was used in the importing module (buildODRType will
automatically use the existing definition and not create a type
declaration).

For Chromium built with -g2, this reduces the aggregate size of the
generated native object files by 66% (from 31G to 10G). It reduced
the time through the ThinLTO link and backend phases by about 20% on
my machine.

Reviewers: mehdi_amini, dblaikie, aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D27775

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289993 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 21:25:01 +00:00
Adrian Prantl
096faa974a Revert "[IR] Remove the DIExpression field from DIGlobalVariable."
This reverts commit 289920 (again).
I forgot to implement a Bitcode upgrade for the case where a DIGlobalVariable
has not DIExpression. Unfortunately it is not possible to safely upgrade
these variables without adding a flag to the bitcode record indicating which
version they are.
My plan of record is to roll the planned follow-up patch that adds a
unit: field to DIGlobalVariable into this patch before recomitting.
This way we only need one Bitcode upgrade for both changes (with a
version flag in the bitcode record to safely distinguish the record
formats).

Sorry for the churn!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289982 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 19:39:01 +00:00
Adrian Prantl
eb38a2a075 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

This reapplies r289902 with additional testcase upgrades.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289920 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 04:25:54 +00:00
Adrian Prantl
7766e56d48 Revert "[IR] Remove the DIExpression field from DIGlobalVariable."
This reverts commit 289902 while investigating bot berakage.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289906 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 01:00:30 +00:00
Adrian Prantl
1b11b0778e [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289902 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 00:36:43 +00:00
Teresa Johnson
731ad19baa [ThinLTO] Thin link efficiency improvement: don't re-export globals (NFC)
Summary:
We were reinvoking exportGlobalInModule numerous times redundantly.
No need to re-export globals referenced by a global that was already
imported from its module. This resulted in a large speedup in the thin
link for a big application, particularly when importing aggressiveness
was cranked up.

Reviewers: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D27687

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289896 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-15 23:50:06 +00:00
Davide Italiano
6b673b85ed [LTO] Reject modules without datalayout.
Also, udpate the ~60 failing tests in the tree which did
not contain a valid datalayout.
This fixes PR31123. lld will be updated in a following patch,
immediately after this is committed.

Differential Revision:  https://reviews.llvm.org/D27082

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289719 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-14 21:57:04 +00:00
Mehdi Amini
dbca62ee4e [ThinLTO] Add an API to trigger file-based API for returning objects to the linker
Summary:
The motivation is to support better the -object_path_lto option on
Darwin. The linker needs to write down the generate object files on
disk for later use by lldb or dsymutil (debug info are not present
in the final binary). We're moving this into libLTO so that we can
be smarter when a cache is enabled and hard-link when possible
instead of duplicating the files.

Reviewers: tejohnson, deadalnix, pcc

Subscribers: dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D27507

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289631 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-14 04:56:42 +00:00
Teresa Johnson
23137e57a7 [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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289441 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-12 16:09:30 +00:00
Peter Collingbourne
8bb25c4bc6 LTO: Hash the parts of the LTO configuration that affect code generation.
Most importantly, we need to hash the relocation model, otherwise we can
end up trying to link non-PIC object files into PIEs or DSOs.

Differential Revision: https://reviews.llvm.org/D27556

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289024 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-08 05:28:30 +00:00
Adam Nemet
55f24b0567 [LTOs] Allow generation of hotness information
The flag is passed by the clang driver.

Differential Revision: https://reviews.llvm.org/D27331

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288519 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-02 17:53:56 +00:00
Adam Nemet
371623998c Make LTO opt-remarks tests matching stricter
This ensures that we don't generate the hotness attribute by default.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288518 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-02 17:53:49 +00:00
Teresa Johnson
7d2e3aa58e [ThinLTO] Stop importing constant global vars as copies in the backend
Summary:
We were doing an optimization in the ThinLTO backends of importing
constant unnamed_addr globals unconditionally as a local copy (regardless
of whether the thin link decided to import them). This should be done in
the thin link instead, so that resulting exported references are marked
and promoted appropriately, but will need a summary enhancement to mark
these variables as constant unnamed_addr.

The function import logic during the thin link was trying to handle
this proactively, by conservatively marking all values referenced in
the initializer lists of exported global variables as also exported.
However, this only handled values referenced directly from the
initializer list of an exported global variable. If the value is itself
a constant unnamed_addr variable, we could end up exporting its
references as well. This caused multiple issues. The first is that the
transitively exported references weren't promoted. Secondly, some could
not be promoted/renamed (e.g. they had a section or other constraint).
recursively, instead of just adding the first level of initializer list
references to the ExportList directly.

Remove this optimization and the associated handling in the function
import backend. SPEC measurements indicate we weren't getting much
from it in any case.

Fixes PR31052.

Reviewers: mehdi_amini

Subscribers: krasin, llvm-commits

Differential Revision: https://reviews.llvm.org/D26880

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288446 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-02 01:02:30 +00:00
Peter Collingbourne
5c1bc63307 llvm-lto2: Simpler workaround for PR30396.
Maintain the command line resolutions as a map to a list of resolutions
rather than a single resolution, and apply the resolutions in the order
observed. This is not only simpler but allows us to test the scenario where
the two symbols have different resolutions.

Differential Revision: https://reviews.llvm.org/D27285

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288288 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-30 23:19:05 +00:00
Adam Nemet
4208630cb7 Rename option to -lto-pass-remarks-output
The new option -pass-remarks-output broke LLVM_LINK_LLVM_DYLIB because
of the duplicate option name with opt.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287627 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-22 07:35:14 +00:00