llvm-project/lld
Jez Ng 82dcf30636 [lld-macho] Use fewer indirections in UnwindInfo implementation
The previous implementation of UnwindInfoSection materialized
all the compact unwind entries & applied their relocations, then parsed
the resulting data to generate the final unwind info. This design had
some unfortunate conseqeuences: since relocations can only be applied
after their referents have had addresses assigned, operations that need
to happen before address assignment must contort themselves. (See
{D113582} and observe how this diff greatly simplifies it.)

Moreover, it made synthesizing new compact unwind entries awkward.
Handling PR50956 will require us to do this synthesis, and is the main
motivation behind this diff.

Previously, instead of generating a new CompactUnwindEntry directly, we
would have had to generate a ConcatInputSection with a number of
`Reloc`s that would then get "flattened" into a CompactUnwindEntry.

This diff introduces an internal representation of `CompactUnwindEntry`
(the former `CompactUnwindEntry` has been renamed to
`CompactUnwindLayout`). The new CompactUnwindEntry stores references to
its personality symbol and LSDA section directly, without the use of
`Reloc` structs.

In addition to being easier to work with, this diff also allows us to
handle unwind info whose personality symbols are located in sections
placed after the `__unwind_info`.

Reviewed By: #lld-macho, oontvoo

Differential Revision: https://reviews.llvm.org/D123276
2022-04-08 23:49:07 -04:00
..
COFF [lld] Remove support for legacy pass manager 2022-04-07 10:17:31 +02:00
Common Cleanup codegen includes 2022-03-16 08:43:00 +01:00
ELF lld/AMDGPU: Fix asserts if no object files are involved in link 2022-04-08 14:18:52 -04:00
MachO [lld-macho] Use fewer indirections in UnwindInfo implementation 2022-04-08 23:49:07 -04:00
MinGW [LLD][MinGW] Add --heap argument support 2022-01-30 00:01:45 +02:00
cmake/modules [CMake] Factor out config prefix finding logic 2022-01-07 20:16:18 +00:00
docs [ELF] Default to --no-fortran-common 2022-03-30 09:12:09 -07:00
include/lld [lld] Make error handling functions opaque 2022-02-17 11:54:57 -08:00
test [lld-macho] Use fewer indirections in UnwindInfo implementation 2022-04-08 23:49:07 -04:00
tools/lld [LLD] Fix issue in HIP due to unspecified order of evaluation of the function object 2022-02-08 19:12:15 -05:00
utils
wasm [lld] Remove support for legacy pass manager 2022-04-07 10:17:31 +02:00
.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 [lld] Require C++14 in LLD standalone build 2022-02-22 18:15:29 -05:00
CODE_OWNERS.TXT
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.