Commit Graph

39 Commits

Author SHA1 Message Date
Rui Ueyama 98e4a5ca11 Simplify.
Instead of Map<StringRef, bool>, we can simply use Set<StringRef>.

llvm-svn: 341948
2018-09-11 14:37:27 +00:00
Rui Ueyama f06d494f46 Improve error message for -thinlto-object-suffix-replace and simplify code.
llvm-svn: 332643
2018-05-17 18:27:12 +00:00
Rumeet Dhindsa 1888326b2d Update ThinLTO Indexing logic
Instead of writing empty index for file, this patch tracks the state of files in ObjectToIndexFileState. If the files are not indexed , only then we emit the empty files

Differential Revision: https://reviews.llvm.org/D46480

llvm-svn: 331803
2018-05-08 20:12:07 +00:00
Rui Ueyama 397dffd81b Split BitcodeCompiler::init() into two functions. NFC.
Previously, code to initialize Backend and code to initialize Conf are
intermingled in init(), though they don't depend on each other.

Differential Revision: https://reviews.llvm.org/D46554

llvm-svn: 331698
2018-05-07 23:24:07 +00:00
Rui Ueyama d54f1c2fed Refactor ThinLTO-related code in BitcodeCompiler.cpp. NFC.
Summary: Refactor ThinLTO-related code in BitcodeCompiler.cpp. NFC.

Reviewers: rdhindsa, espindola

Subscribers: emaste, inglorion, arichardson, llvm-commits, eraman

Differential Revision: https://reviews.llvm.org/D46549

llvm-svn: 331689
2018-05-07 22:11:24 +00:00
Rui Ueyama 66a9f257b6 Refactor BitcodeCompiler::createLTO. NFC.
llvm-svn: 331655
2018-05-07 17:46:28 +00:00
Rumeet Dhindsa d366e36bbf Added support for ThinLTO plugin options : thinlto-index-only and thinlto-prefix-replace
Differential Revision: https://reviews.llvm.org/D46034

llvm-svn: 331405
2018-05-02 21:40:07 +00:00
Rui Ueyama 3f851704c1 Move new lld's code to Common subdirectory.
New lld's files are spread under lib subdirectory, and it isn't easy
to find which files are actually maintained. This patch moves maintained
files to Common subdirectory.

Differential Revision: https://reviews.llvm.org/D37645

llvm-svn: 314719
2017-10-02 21:00:41 +00:00
Rafael Espindola 4b075bb218 Make __start_sec __end_sec handling more precise.
With this we only ask LTO to keep a C named section if there is a
__start_ or __end symbol.

This is not as strict as lld's --gc-sections, but is as good as we can
get without having a far more detailed ir summary.

llvm-svn: 309232
2017-07-26 23:39:10 +00:00
George Rimar 67c60727ce [ELF] - Apply clang-format. NFC.
llvm-svn: 308297
2017-07-18 11:55:35 +00:00
Peter Collingbourne e02775f068 ELF: Add ThinLTO caching support.
This patch adds an option named --thinlto-cache-dir, which specifies the
path to a directory in which to cache native object files for ThinLTO
incremental builds.

Differential Revision: https://reviews.llvm.org/D30509

llvm-svn: 296702
2017-03-01 23:00:10 +00:00
Peter Smith 3a52eb0054 [ELF] Use SyntheticSections for Thunks
Thunks are now implemented by redirecting the relocation to the
symbol S, to a symbol TS in a Thunk. The Thunk will transfer control
to S. This has the following implications:
- All the side-effects of Thunks happen within createThunks()
- Thunks are no longer stored in InputSections and Symbols no longer
  need to hold a pointer to a Thunk
- The synthetic Thunk sections need to be merged into OutputSections
    
This implementation is almost a direct conversion of the existing
Thunks with the following exceptions:
- Mips LA25 Thunks are placed before the InputSection that defines
  the symbol that needs a Thunk.
- All ARM Thunks are placed at the end of the OutputSection of the
  first caller to the Thunk.
    
Range extension Thunks are not supported yet so it is optimistically
assumed that all Thunks can be reused.

This is a recommit of r293283 with a fixed comparison predicate as
std::merge requires a strict weak ordering.

Differential revision: https://reviews.llvm.org/D29327

llvm-svn: 293757
2017-02-01 10:26:03 +00:00
Rui Ueyama f20ee9f11a Revert "[ELF][ARM] Use SyntheticSections for Thunks"
This reverts commit r293283 because it broke MSVC build.

llvm-svn: 293352
2017-01-28 00:48:06 +00:00
Peter Smith 5191c6f945 [ELF][ARM] Use SyntheticSections for Thunks
Thunks are now implemented by redirecting the relocation to the
symbol S, to a symbol TS in a Thunk. The Thunk will transfer control
to S. This has the following implications:
- All the side-effects of Thunks happen within createThunks()
- Thunks are no longer stored in InputSections and Symbols no longer
  need to hold a pointer to a Thunk
- The synthetic Thunk sections need to be merged into OutputSections
    
This implementation is almost a direct conversion of the existing
Thunks with the following exceptions:
- Mips LA25 Thunks are placed before the InputSection that defines
  the symbol that needs a Thunk.
- All ARM Thunks are placed at the end of the OutputSection of the
  first caller to the Thunk.
    
Range extension Thunks are not supported yet so it is optimistically
assumed that all Thunks can be reused.

Differential Revision:  https://reviews.llvm.org/D29129

llvm-svn: 293283
2017-01-27 13:10:16 +00:00
Peter Smith 97c6d78f3e [ELF] Add support for thunks to undefined non-weak symbols
In a shared library an undefined symbol is implicitly imported. If the
symbol is called as a function a PLT entry is generated for it. When the
caller is a Thumb b.w a thunk to the PLT entry is needed as all PLT
entries are in ARM state.
    
This change allows undefined symbols to have thunks in the same way that
shared symbols may have thunks.

llvm-svn: 290951
2017-01-04 09:45:45 +00:00
Davide Italiano 3bfa081aa9 [ELF] Be compliant with LLVM and rename Lto into LTO. NFCI.
llvm-svn: 287967
2016-11-26 05:37:04 +00:00
Rui Ueyama 55518e7dd8 Consolidate BumpPtrAllocators.
Previously, we have a lot of BumpPtrAllocators, but all these
allocators virtually have the same lifetime because they are
not freed until the linker finishes its job. This patch aggregates
them into a single allocator.

Differential revision: https://reviews.llvm.org/D26042

llvm-svn: 285452
2016-10-28 20:57:25 +00:00
Rafael Espindola 5da1d88492 Reduce the number of allocators.
We used to have one allocator per file, which reduces the advantage of
using an allocator in the first place.

This is a small speed up is most cases. The largest speedup was in
1.014X in chromium no-gc. The largest slowdown was scylla at 1.003X.

llvm-svn: 285205
2016-10-26 15:34:24 +00:00
Rui Ueyama 1cc007aeae Keep a private member private.
llvm-svn: 282798
2016-09-29 22:37:45 +00:00
Rui Ueyama 0f327380bf Attempt to fix Windows buildbots.
llvm-svn: 282670
2016-09-29 01:59:03 +00:00
Rui Ueyama e8b2df47a3 Remove unused #includes.
llvm-svn: 282668
2016-09-29 01:45:22 +00:00
Davide Italiano 786d8e33db [ELF/LTO] Switch to the new resolution-based API.
Differential Revision:  https://reviews.llvm.org/D24492

llvm-svn: 282656
2016-09-29 00:40:08 +00:00
Rui Ueyama 38dbd3eea9 Simplify InputFile ownership management.
Previously, all input files were owned by the symbol table.
Files were created at various places, such as the Driver, the lazy
symbols, or the bitcode compiler, and the ownership of new files
was transferred to the symbol table using std::unique_ptr.
All input files were then free'd when the symbol table is freed
which is on program exit.

I think we don't have to transfer ownership just to free all
instance at once on exit.

In this patch, all instances are automatically collected to a
vector and freed on exit. In this way, we no longer have to
use std::unique_ptr.

Differential Revision: https://reviews.llvm.org/D24493

llvm-svn: 281425
2016-09-14 00:05:51 +00:00
Rui Ueyama 601b07c7f5 ELF: Remove member variables that are used only in one function.
Differential Revision: https://reviews.llvm.org/D22396

llvm-svn: 275526
2016-07-15 03:06:42 +00:00
Davide Italiano 595ee8cb9c [LTO] Include ASM undefs in llvm.compiler_used.
This fixes PR28218. Thanks to Rafael for spotting a failure in
the SHARED_LIBS build!

Differential Revision:  http://reviews.llvm.org/D21577

llvm-svn: 273451
2016-06-22 18:09:23 +00:00
Rafael Espindola 0de48c393d Delete dead variable.
llvm-svn: 267935
2016-04-28 20:29:12 +00:00
Rafael Espindola 156f4ee1c0 Use a single context for lto.
Using multiple context used to be a really big memory saving because we
could free memory from each file while the linker proceeded with the
symbol resolution. We are getting lazier about reading data from the
bitcode, so I was curious if this was still a good tradeoff.

One thing that is a bit annoying is that we still have to copy the
symbol names. The problem is that the names are stored in the Module and
get freed when we move the module bits during linking.

Long term I think the solution is to add a symbol table to the bitcode.
That way IRObject file will not need to use a Module or a Context and we
can drop it while still keeping a StringRef to the names.

This patch is still be an interesting medium term improvement.

When linking llvm-as without debug info this patch is a small speedup:

master: 29.861877513 seconds
patch: 29.814533787 seconds

With debug info the numbers are

master: 34.765181469 seconds
patch: 34.563351584 seconds

The peak memory usage when linking llvm-as with debug info was

master: 599.10MB
patch: 600.13MB
llvm-svn: 267921
2016-04-28 19:30:41 +00:00
Rui Ueyama b29465fe47 Remove unused #include.
llvm-svn: 267222
2016-04-22 21:17:55 +00:00
Rui Ueyama 412c802bda Move BitcodeCompiler constructor to the .cpp file. NFC.
llvm-svn: 267221
2016-04-22 21:16:18 +00:00
Davide Italiano 3c0410d09d [LTO] Discard names for Values that are not global.
This is not on by default (but it might be in the future).
The knob to enable the optimization is -lto-discard-value-names.

llvm-svn: 266953
2016-04-21 04:46:22 +00:00
Duncan P. N. Exon Smith 28d8d04657 LTO: Adapt to LLVM API changes in r266713
llvm-svn: 266714
2016-04-19 04:57:40 +00:00
Rafael Espindola abf6c650ac Make CreateTargetMachine as small as possible.
It is a pity that we have to create a TargetMachine once per thread,
so at least make that code as small as possible.

llvm-svn: 266578
2016-04-17 23:20:08 +00:00
Duncan P. N. Exon Smith 2c66b23d79 LTO: Merge debug info types when linking bitcode
Make sure lld enables ODR type uniquing for debug info when invoking
LTO, as a follow-up to LLVM r266549.

llvm-svn: 266555
2016-04-17 07:35:38 +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
Davide Italiano 15c41b25c7 [LTO] Switch Module to std::unique_ptr<>.
Differential Revision:   http://reviews.llvm.org/D18994

llvm-svn: 266009
2016-04-11 22:39:51 +00:00
Rui Ueyama 01ddc06484 Make BitcodeCompiler::compile a non-template function. NFC.
llvm-svn: 264770
2016-03-29 19:08:46 +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
Rui Ueyama 961f2ff21e ELF: Split BitcodeCompiler::compile.
http://reviews.llvm.org/D18410

llvm-svn: 264193
2016-03-23 21:19:27 +00:00
Rui Ueyama 259924869b ELF: Create LTO.{cpp,h} and move LTO-related code to that file.
The code for LTO has been growing, so now is probably a good time to
move it to its own file. SymbolTable.cpp is for symbol table, and
because compiling bitcode files are semantically not a part of
symbol table, this is I think a good thing to do.

http://reviews.llvm.org/D18370

llvm-svn: 264091
2016-03-22 20:52:10 +00:00