llvm-project/lld
Jez Ng f6b6e72143 [lld-macho] Factor out common InputSection members
We have been creating many ConcatInputSections with identical values due
to .subsections_via_symbols. This diff factors out the identical values
into a Shared struct, to reduce memory consumption and make copying
cheaper.

I also changed `callSiteCount` from a uint32_t to a 31-bit field to save an
extra word.

All in all, this takes InputSection from 120 to 72 bytes (and
ConcatInputSection from 160 to 112 bytes), i.e. 30% size reduction in
ConcatInputSection.

Numbers for linking chromium_framework on my 3.2 GHz 16-Core Intel Xeon W:

      N           Min           Max        Median           Avg        Stddev
  x  20          4.14          4.24          4.18         4.183   0.027548999
  +  20          4.04          4.11         4.075        4.0775   0.018027756
  Difference at 95.0% confidence
          -0.1055 +/- 0.0149005
          -2.52211% +/- 0.356215%
          (Student's t, pooled s = 0.0232803)

Reviewed By: #lld-macho, thakis

Differential Revision: https://reviews.llvm.org/D105305
2021-07-01 21:22:39 -04:00
..
COFF [LLD] [COFF] Fix handling of LTO comdats with nontrivial selection types after 728cc0075e 2021-06-25 09:39:56 +03:00
Common [lld] Rename StringRef _lower() method calls to _insensitive() 2021-06-25 00:22:01 +03:00
ELF [ELF] Preserve section order within an INSERT AFTER command 2021-06-30 11:35:50 -07:00
MachO [lld-macho] Factor out common InputSection members 2021-07-01 21:22:39 -04:00
MinGW [OptTable] Rename PrintHelp to printHelp 2021-06-24 14:47:03 -07:00
cmake/modules [cmake] Add support for multiple distributions 2021-05-12 11:13:18 -07:00
docs [lld][WebAssembly] Add new `--import-undefined` option 2021-06-17 11:44:21 -07:00
include/lld [WebAssembly] Rename event to tag 2021-06-17 20:34:19 -07:00
lib [OptTable] Rename PrintHelp to printHelp 2021-06-24 14:47:03 -07:00
test [lld-macho] Deduplicate CFStrings 2021-07-01 21:22:38 -04:00
tools/lld [lld] Rename StringRef _lower() method calls to _insensitive() 2021-06-25 00:22:01 +03:00
unittests Use INTERFACE_COMPILE_OPTIONS to disable -Wsuggest-override for any target that links to gtest 2020-07-27 08:37:01 -07:00
utils
wasm [OptTable] Rename PrintHelp to printHelp 2021-06-24 14:47:03 -07:00
.clang-format
.clang-tidy NFC: .clang-tidy: Inherit configs from parents to improve maintainability 2021-06-08 08:25:59 -07:00
.gitignore
CMakeLists.txt Fix lld macho standalone build by including llvm/Config/llvm-config.h instead of llvm/Config/config.h 2021-05-19 11:15:07 -04:00
CODE_OWNERS.TXT Add code owners of new MachO port 2020-09-02 19:32:12 -07:00
LICENSE.TXT
README.md [doc] Place sha256 in lld/README.md into backticks 2021-01-12 10:19:40 -08:00

README.md

LLVM Linker (lld)

This directory and its subdirectories contain source code for the LLVM Linker, a modular cross platform linker which is built as part of the LLVM compiler infrastructure project.

lld is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt.

Benchmarking

In order to make sure various developers can evaluate patches over the same tests, we create a collection of self contained programs.

It is hosted at https://s3-us-west-2.amazonaws.com/linker-tests/lld-speed-test.tar.xz

The current sha256 is 10eec685463d5a8bbf08d77f4ca96282161d396c65bd97dc99dbde644a31610f.