4e958b4d7c
The main motivation for this change is to avoid ambiguity because mapping symbol names may not be unique across a binary and do not allow uniquely identifying target address. So that mapping symbols used as branch target labels make llvm-objdump output less readable. Another point is that mapping symbols sometimes appear in non-allocatable sections, like debug info sections which make objdump output even more confusing. For example, a small AArch64 executable may contain plenty of `$d[.*]` symbols and none of them would be useful as a label for resolving a branch or a memory operand target address: ``` 0000000000000254 l .note.ABI-tag 0000000000000000 $d 00000000000008d4 l .eh_frame 0000000000000000 $d 0000000000000868 l .rodata 0000000000000000 $d 0000000000011028 l .data 0000000000000000 $d 0000000000010db8 l .fini_array 0000000000000000 $d 0000000000010db0 l .init_array 0000000000000000 $d 00000000000008e8 l .eh_frame 0000000000000000 $d 0000000000011034 l .bss 0000000000000000 $d ``` Note that GNU objdump doesn't use mapping symbols as branch target labels for all targets that support such symbols (ARM, AArch64, CSKY). Differential Revision: https://reviews.llvm.org/D139131
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.