maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity
llvm-project/lld
History
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
..
COFF Fix Clang-tidy misc-unused-using-decls and Include What You Use warnings. 2016-04-21 17:14:10 +00:00
ELF Use a single context for lto. 2016-04-28 19:30:41 +00:00
cmake/modules
…
docs Remove links to deleted TODOs. 2016-04-16 11:11:56 +00:00
include/lld Needed change to lld for the change to libObject’s getName() for symbols now returning Expected<...> 2016-04-20 21:24:51 +00:00
lib Fix builds broken in r267008. 2016-04-21 17:27:04 +00:00
test Skip scanRelocs for non-alloc sections. 2016-04-28 18:42:04 +00:00
tools/lld Inline a trivial CMakeLists.txt. 2016-03-03 01:56:23 +00:00
unittests Fix Clang-tidy misc-unused-using-decls and Include What You Use warnings. 2016-04-21 17:14:10 +00:00
.arcconfig Update Phabricator server. 2014-04-07 04:52:24 +00:00
.clang-format Remove redundant "Standard: Cpp11" tag. The LLVM style has used the 2014-07-04 12:08:03 +00:00
.gitignore Update .gitignore to ignore hidden MacOSX Finder droppings 2014-07-16 21:01:17 +00:00
CMakeLists.txt Inline a trivial CMakeLists.txt. 2016-03-03 01:56:23 +00:00
CODE_OWNERS.TXT Add initial CODE_OWNERS.TXT file 2015-07-25 00:44:37 +00:00
LICENSE.TXT Update copyright year to 2016. 2016-03-30 22:40:59 +00:00
README.md
…

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.