forked from OSchip/llvm-project
4f38ab250f
ELF for the ARM architecture requires linkers to provide interworking for symbols that are of type STT_FUNC. Interworking for other symbols must be encoded directly in the object file. LLD was always providing interworking, regardless of the symbol type, this breaks some programs that have branches from Thumb state targeting STT_NOTYPE symbols that have bit 0 clear, but they are in fact internal labels in a Thumb function. LLD treats these symbols as ARM and inserts a transition to Arm. This fixes the problem for in range branches, R_ARM_JUMP24, R_ARM_THM_JUMP24 and R_ARM_THM_JUMP19. This is expected to be the vast majority of problem cases as branching to an internal label close to the function. There is at least one follow up patch required. - R_ARM_CALL and R_ARM_THM_CALL may do interworking via BL/BLX substitution. In theory range-extension thunks can be altered to not change state when the symbol type is not STT_FUNC. I will need to check with ld.bfd to see if this is the case in practice. Fixes (part of) https://github.com/ClangBuiltLinux/linux/issues/773 Differential Revision: https://reviews.llvm.org/D73474 |
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| .. | ||
| COFF | ||
| Common | ||
| ELF | ||
| MinGW | ||
| cmake/modules | ||
| docs | ||
| include/lld | ||
| lib | ||
| test | ||
| tools/lld | ||
| unittests | ||
| utils | ||
| wasm | ||
| .arcconfig | ||
| .clang-format | ||
| .gitignore | ||
| CMakeLists.txt | ||
| CODE_OWNERS.TXT | ||
| LICENSE.TXT | ||
| 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.
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.