Commit Graph

62 Commits

Author SHA1 Message Date
Davide Italiano 493b683f79 [LTO] Don't crash on a BitcodeFile without DataLayout.
Emit an error instead.

llvm-svn: 266504
2016-04-16 01:33:33 +00:00
Davide Italiano 0ce90908e0 [LTO] Add datalayout to test to prevent an assertion in Debug mode.
While here, run this test only on x86.

llvm-svn: 266487
2016-04-15 22:58:57 +00:00
Davide Italiano bc176631cd [LTO] Implement parallel Codegen for LTO using splitCodeGen.
Parallelism level can be chosen using the new --lto-jobs=K option
where K is the number of threads used for CodeGen. It currently
defaults to 1.

llvm-svn: 266484
2016-04-15 22:38:10 +00:00
Peter Collingbourne 7cf73ec4c7 ELF: Implement basic support for module asm in bitcode files.
Differential Revision: http://reviews.llvm.org/D18872

llvm-svn: 265956
2016-04-11 16:39:43 +00:00
Rui Ueyama 029d89ee57 Fix another crash bug in --start-lib.
The previous fix didn't work for bitcode files. This patch fixes
the remaining issue.

llvm-svn: 265854
2016-04-08 21:38:22 +00:00
Rui Ueyama f8baa66056 ELF: Implement --start-lib and --end-lib
start-lib and end-lib are options to link object files in the same
semantics as archive files. If an object is in start-lib and end-lib,
the object is linked only when the file is needed to resolve
undefined symbols. That means, if an object is in start-lib and end-lib,
it behaves as if it were in an archive file.

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

http://reviews.llvm.org/D18814

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

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

llvm-svn: 265536
2016-04-06 13:22:41 +00:00
Rafael Espindola 5cea969dca Fix another case of propagating IsUsedRegularObj.
I have an idea on how to clean this up, but lets get the tests passing
first.

llvm-svn: 265374
2016-04-05 01:38:43 +00:00
Peter Collingbourne c393c028a9 Add triple to llvm-mc command line. Should fix Windows bot.
llvm-svn: 265373
2016-04-05 01:05:42 +00:00
Peter Collingbourne e8afa4971c ELF: Preserve MustBeInDynSym for bitcode symbols.
Make sure to copy the MustBeInDynSym field when replacing shared symbols with
bitcode symbols, and when replacing bitcode symbols with regular symbols
in addCombinedLtoObject. Fixes interposition of DSO symbols with bitcode
symbols in the main executable.

Differential Revision: http://reviews.llvm.org/D18780

llvm-svn: 265371
2016-04-05 00:47:55 +00:00
Rui Ueyama d575edb780 Fix -disable-verify test.
This test didn't actually test the functionality. The new test
verifies that "-verify" is passed if and only if -disable-verify
is not given.

llvm-svn: 265316
2016-04-04 17:42:01 +00:00
Davide Italiano 842fa53026 [LTO] Implement -disable-verify, which disables bitcode verification.
So, there are some cases when the IR Linker produces a broken
module (which doesn't pass the verifier) and we end up asserting
inside the verifier. I think it's always a bug producing a module
which does not pass the verifier but there are some cases in which
people can live with the broken module (e.g. if only DebugInfo
metadata are broken). The gold plugin has something similar.

This commit is motivated by a situation I found in the
wild. It seems that somebody else discovered it independently
and reported in PR24923.

llvm-svn: 265258
2016-04-03 03:39:09 +00:00
Davide Italiano 88dbd3b1cf [LTO] Add a test to ensure we reject negative opt level.
We already got this right, but it never hurts adding another
test, in case we'll change the handling in the future, to ensure
we don't break it.

llvm-svn: 265256
2016-04-03 03:12:00 +00:00
Davide Italiano 8848d44e46 [LTO] Reject invalid optimization levels.
llvm-svn: 265255
2016-04-03 02:41:15 +00:00
Davide Italiano 887d76c392 [LTO] Fix -save-temps in case -o is not specified.
Currently we create a file called .lto.bc. In UNIX,
ls(1) by default doesn't show up files starting with
a dot, as they're (only by convention) hidden.
This makes the output of -save-temps a little bit
hard to find. Use "a.out.lto.bc" instead if the
output file is not specified.

While here, change an existing -save-temps test to
exercise this more interesting behaviour.

llvm-svn: 265254
2016-04-03 02:16:56 +00:00
Davide Italiano 4fda708624 [LTO] Fix symbols which were internalized incorrectly.
If a symbol is defined in an archive, when we replace its body
the isUsedInRegularObj wasn't set correctly. Internalize makes
its decision based on that bit so we ended up internalizing
symbols that we shouldn't (because they're referenced).
This should fix. Thanks to Peter and Rafael for discussion
and help diagnosing the issue!

Found during LTO of unittests.

llvm-svn: 265208
2016-04-02 02:10:40 +00:00
Sean Silva 8e4ad5dbf8 PR27104: Add -mllvm option
The argv[0] is based on the analogous thing in clang.

llvm-svn: 265206
2016-04-02 01:39:56 +00:00
Davide Italiano 8eca282dc9 [LTO] Inherit options from Codegen before initializing TargetMachine.
This fixes bootstrap of llvm-tblgen (with LTO) and PR27150.
Slightly longer explanation follows.

Emission of .init_array instead of .ctors is supported only on a
subset of the Target LLVM supports. Codegen needs to be conservative
and always emit .ctors unless instructed otherwise (based on target).
If the dynamic linker sees .init_array it completely ignores
what's inside .ctors and therefore some constructors are not called
(and this causes llvm-tblgen to crash on startup).

Teach LLD/LTO about the Codegen options so we end up always emitting
.init_array and avoid this issue.
In future, we might end up supporting mix of .ctors and .init_array
in different input files if this shows up as a real-world use case.
The way gold handles this case is mapping .ctors from input into
.init_array in output. There's also another caveat because
as far as I understand .ctors run in reverse order so when we do
the copy/mapping we need to reverse copy in the output if there's
more than one ctor. That's why I'd rather avoid this complicate logic
unless there's a real need.

An analogous reasoning holds for .dtors/.fini_array.

llvm-svn: 265085
2016-04-01 00:35:29 +00:00
Peter Collingbourne ed22f9b6f1 ELF: Add flag for controlling LTO optimization level.
Differential Revision: http://reviews.llvm.org/D18667

llvm-svn: 265053
2016-03-31 21:00:27 +00:00
Davide Italiano bbaf5e0acf [LTO] Add a test to ensure we treat externally available symbols correctly.
We already get it right, but there was no coverage for it.

llvm-svn: 264925
2016-03-30 21:01:14 +00:00
Davide Italiano 86f2bd5ca1 [LTO] Teach LTO about @llvm.used global.
If a symbol appears in @llvm.used, the linker is forced to treat
the symbol as there's a reference to it.

llvm-svn: 264790
2016-03-29 21:46:35 +00:00
George Rimar 86971050cb [ELF] - Error out when R_X86_64_PC32/R_X86_64_32 are used against preemptible symbol when linking shared object.
When R_X86_64_PC32/R_X86_64_32 relocations are
used against preemptible symbol and output is position independent,
error should be generated.

Differential revision: http://reviews.llvm.org/D18190

llvm-svn: 264707
2016-03-29 08:35:42 +00:00
Davide Italiano 3acdfeee11 [LTO] Don't internalize if --export-dynamic is passed.
We treat that in the same way we treat shared libraries.

llvm-svn: 264698
2016-03-29 04:34:09 +00:00
Davide Italiano 04d6aa2b38 [LTO] Include in .symtab/.dynsym symbols introduced by optimizations.
Some optimizations, e.g. SimplifyLibCalls, can replace functions with
others as part of the lowering, e.g. printf => puts.
The new symbols don't have the isUsedInRegularObj flag set so they
don't get included in the final symbol table (and dynamic symbol
table), and the dynamic linker gets confused. Include  them as a fix.

Differential Revision: http://reviews.llvm.org/D18357

llvm-svn: 264688
2016-03-29 00:15:52 +00:00
Davide Italiano 828ac541ef [LTO] Internalize symbols.
IPO doesn't work very well across symbols referenced
by others TUs. The linker here tries to evaluate
which symbols are safe to internalize and switches
their linkage.

Differential Revision:  http://reviews.llvm.org/D18415

llvm-svn: 264585
2016-03-28 15:44:21 +00:00
Simon Atanasyan 628fe404f7 [ELF] Follow-up to r264300. Update test case expectations to reflect recent changes in llvm-readobj. NFC.
llvm-svn: 264304
2016-03-24 16:30:20 +00:00
Davide Italiano bcd660a908 [LTO] Keep linkonce symbols when required.
Similarly to how we do with linkonce_odr symbols already, but
change their linkage to weak.

llvm-svn: 264181
2016-03-23 18:41:48 +00:00
Davide Italiano 6af61dec1c [LTO/Tests] Fix typo. Visibility -> Linkage. Pointy-hat to me.
llvm-svn: 264176
2016-03-23 18:15:06 +00:00
Davide Italiano 1de78202e8 [LTO/tests] Check optimized bitcode instead of produced shared library.
As requested by Rafael.

llvm-svn: 264175
2016-03-23 18:13:32 +00:00
Davide Italiano da45298e58 [Tests] Remove the correct files.
llvm-svn: 264136
2016-03-23 03:20:46 +00:00
Sean Silva 009ea26358 Tidy up this test a bit.
llvm-svn: 264117
2016-03-22 23:19:40 +00:00
Davide Italiano d4c2a03c32 [LTO] Keep linkonce_odr symbols when appropriate.
Ensure we keep the symbol we need to before it reaches
the Writer (and hit an assertion), changing its linkage
from linkonce_odr to weak. For a more detailed description
of the problem, see PR19901 where a similar problem was
fixed for the gold plugin. Thanks to Rafael for providing
a testcase.

llvm-svn: 264111
2016-03-22 22:31:34 +00:00
Sean Silva 3baa23b50c [lto] Provide a file name for the combined LTO object.
Otherwise, we get diagnostics like:

    undefined symbol: foo in

Which isn't particularly useful.

llvm-svn: 264089
2016-03-22 20:25:32 +00:00
Davide Italiano e043c0c68c [LTO] Test lto passes are actually working.
This should have been part of r263761.

llvm-svn: 263763
2016-03-17 23:36:31 +00:00
George Rimar 5761042db7 This reverts the r263125
It was discussed to make all messages be 
lowercase to be consistent with clang.
(also reverts the r263128 which fixed 
build bot fail after r263125)

Original commit message:
[ELF] - Consistent spelling for error/warning messages

Previously error and warnings were not consistent in lld.
Some of them started from lowercase letter, others from
uppercase. Also there was one or two which had a dot at the end.
This patch changes all messages to start from uppercase letter if
they were not before.

Differential revision: http://reviews.llvm.org/D18045

llvm-svn: 263240
2016-03-11 14:43:02 +00:00
Sean Silva 4a0ff22d51 [lto] The previous testcase was not useful enough.
-shared was hiding the fact that the intrinsic wasn't being found.

llvm-svn: 263197
2016-03-11 05:42:34 +00:00
Sean Silva b1069239a0 [lto] Add a useful test case.
This is reduced from an issue found in practice.
The original version of D18012 needed another patch to handle this, but
it now works since we are using a more correct GV->hasAppendingLinkage()
check that Rafael suggested.

This is what remains of that other patch.

llvm-svn: 263181
2016-03-11 01:10:37 +00:00
Sean Silva b1b5cc83f1 [lto] Make sure that ctors are added to the combined module.
Summary:
More generally, appending linkage is a special case that we don't want
to create a SymbolBody for.

Reviewers: rafael, ruiu

Subscribers: Bigcheese, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D18012

llvm-svn: 263179
2016-03-11 00:50:05 +00:00
Sean Silva e8f5dded0d Tighten up this test a bit.
Thanks to Rafael to spotting this in the post-commit review of r263070.

llvm-svn: 263178
2016-03-11 00:48:36 +00:00
George Rimar e094388861 [ELF] - Consistent spelling for error/warning messages
Previously error and warnings were not consistent in lld.
Some of them started from lowercase letter, others from
uppercase. Also there was one or two which had a dot at the end.
This patch changes all messages to start from uppercase letter if
they were not before.

Differential revision: http://reviews.llvm.org/D18045

llvm-svn: 263125
2016-03-10 16:58:34 +00:00
Sean Silva 03e41ee6a7 [lto] Initialize asmparsers.
Summary:
They are needed for inline asm during LTO.

In particular we hit the report_fatal_error on
llvm/lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp:138

    LLVM ERROR: Inline asm not supported by this streamer because we don't have an asm parser for this target

Reviewers: ruiu, rafael

Subscribers: Bigcheese, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D18027

llvm-svn: 263094
2016-03-10 04:58:52 +00:00
Sean Silva 1c82b7f64d Use %t as the output file name to avoid repetition. NFC.
llvm-svn: 263071
2016-03-09 22:30:09 +00:00
Sean Silva 4aaeac6ad3 [lto] Add saving the LTO .o file to -save-temps.
Summary:
This implements another part of -save-temps.
After this, the only remaining part is dumping the optimized bitcode. But
currently LLD's LTO doesn't have a non-intrusive place to put this.
Eventually we probably will and it will make sense to add it then.

Reviewers: ruiu, rafael

Subscribers: joker.eph, Bigcheese, llvm-commits

Differential Revision: http://reviews.llvm.org/D18009

llvm-svn: 263070
2016-03-09 22:30:05 +00:00
Sean Silva 35ef3d95eb [lto] Add beginning of -save-temps option.
Summary:
This is useful for debugging issues with LTO.
The option follows the analogous option in ld64 and the gold plugin (per
Rafael's suggestion).

For starters, this only dumps the combined bitcode file.
In a future patch I will add dumping for the .o file.

The naming of the output follows ld64's convention which is slightly more
consistent IMO (consistent `.lto.<extension>` for all the files).

Reviewers: rafael, ruiu

Subscribers: joker.eph, Bigcheese, llvm-commits

Differential Revision: http://reviews.llvm.org/D18006

llvm-svn: 263055
2016-03-09 20:01:08 +00:00
Sean Silva 50d27ff3c1 [lto] Don't lazy load metadata for now.
Summary:
At the very least we hit

    Assertion failed: (((Flags & RF_HaveUnmaterializedMetadata) || Node->isResolved()) && "Unexpected unresolved node"), function MapMetadataImpl, file /Users/Sean/pg/llvm/lib/Transforms/Utils/ValueMapper.cpp, line 375.

on the included test case.

We currently do things like parse the module twice to keep the
implementation minimal. I think it makes sense to add start with eager
loading for similar reasons.

Reviewers: rafael

Subscribers: ruiu, Bigcheese, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D17982

llvm-svn: 263045
2016-03-09 18:38:40 +00:00
Sean Silva 7255d0b068 [lto] Avoid duplicate symbol error for appending linkage.
Summary:
Is there any other code needed for correctly handling appending linkage?
Do we need to do something more with @llvm.global_ctors in
SymbolTable.cpp:addBitcodeFile; otherwise the combined bitcode module
won't have all the global ctors.

Reviewers: rafael

Subscribers: Bigcheese, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D17975

llvm-svn: 262992
2016-03-09 03:42:39 +00:00
Sean Silva 31a5ab9e3b [lto] Record whether a variable is TLS.
Summary:

Reviewers: rafael

Subscribers: Bigcheese, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D17974

llvm-svn: 262975
2016-03-09 00:47:47 +00:00
Sean Silva b284e71e03 [lto] Don't add variables with private linkage to the symbol table.
Summary:
This causes the issue in PR26872 to go away now that we aren't creating
symbols for the string literals, but that may just be concealing a
deeper problem, so best to keep that PR open.

Reviewers: rafael

Subscribers: Bigcheese, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D17971

llvm-svn: 262968
2016-03-08 23:50:56 +00:00
Rafael Espindola 37bcaac179 Add support for common symbols.
llvm-svn: 262848
2016-03-07 19:15:57 +00:00
Rafael Espindola 4f29c1a337 lto: Record visibility in defined symbols.
llvm-svn: 262835
2016-03-07 17:14:36 +00:00