On Wed, 13 Oct 2021 13:55:04 GMT, Andrew Haley <a...@openjdk.org> wrote:
>> This patch expands the newly added system for hsdis backends to include LLVM. >> >> The actual code in hsdis-llvm.cpp is based heavily on the work by @luhenry, >> as published in the never integrated PR >> https://github.com/openjdk/jdk/pull/392. (I have basically just ripped out >> the binutils-based part of it.) >> >> Unfortunately I have not been able to make this work properly on Windows. >> With some additional flags I made it compile without complaints, but it >> caused hotspot to segfault in `LoadLibrary` (!) in `os::dll_load` when I >> tried to load the library. This is somewhat ironic, since the initial >> implementation was created by Ludovic for the very purpose of using it on >> Windows. >> >> The lack of Windows support in this patch does not mean it is impossible to >> get it to work, just that I need to co-operate with someone who has more >> experience of compiling LLVM on Windows, and/or are more eager to get this >> combination to work. > >> This patch expands the newly added system for hsdis backends to include LLVM. >> >> The actual code in hsdis-llvm.cpp is based heavily on the work by @luhenry, >> as published in the never integrated PR #392. (I have basically just ripped >> out the binutils-based part of it.) >> >> Unfortunately I have not been able to make this work properly on Windows. > > What is it for, then? > > hsdis builds on AArch64-MacOS-LLVM with > > > cd src/utils/hsdis > mkdir build > cd build > git clone https://github.com/bminor/binutils-gdb > ln -s binutils-gdb binutils > cd .. > make > @theRealAph As you might be aware, the licensing criteria for binutils makes > it impossible to distribute a binutils-based hsdis with the JDK. While IANAL, > my understanding is that the LLVM license is less problematic in that way. > > Also, this is to allow a bit of freedom of choice. If you prefer the LLVM > backend (I've been told that it generates better disassembly in some case) > you should be able to select it. > > And finally, I do think that the LLVM backend should be able to work on > Windows, too. It's just that this is tricky enough to motivate doing this in > a separate, later, step. OK, but how do you build it? I have applied this patch, and the instructions in `hsdis/README` don't mention LLVM, just binutils. Shouldn't the instructions have been updated? ------------- PR: https://git.openjdk.java.net/jdk/pull/5920
