| commit | e4b5aac85445af4c86d81499ace9a59b434859cd | [log] [tgz] |
|---|---|---|
| author | Fangrui Song <maskray@google.com> | Wed Sep 25 03:39:31 2019 +0000 |
| committer | Fangrui Song <maskray@google.com> | Wed Sep 25 03:39:31 2019 +0000 |
| tree | d95f95609f40cb3bbf4d4b2693c7daf5fd15e79e | |
| parent | 2a6ee260cd30932ba84de8e8a4aa40131f694ec7 [diff] |
[ELF] Add -z separate-loadable-segments to complement separate-code and noseparate-code D64906 allows PT_LOAD to have overlapping p_offset ranges. In the default R RX RW RW layout + -z noseparate-code case, we do not tail pad segments when transiting to another segment. This can save at most 3*maxPageSize bytes. a) Before D64906, we tail pad R, RX and the first RW. b) With -z separate-code, we tail pad R and RX, but not the first RW (RELRO). In some cases, b) saves one file page. In some cases, b) wastes one virtual memory page. The waste is a concern on Fuchsia. Because it uses compressed binaries, it doesn't benefit from the saved file page. This patch adds -z separate-loadable-segments to restore the behavior before D64906. It can affect section addresses and can thus be used as a debugging mechanism (see PR43214 and ld.so partition bug in crbug.com/998712). Reviewed By: jakehehrlich, ruiu Differential Revision: https://reviews.llvm.org/D67481 git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@372807 91177308-0d34-0410-b5e6-96231b3b80d8
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.
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.