Add PowerPC64 support for FreeBSD

[lenoil98]

Is there any interest into adding support for FreeBSD/PowerPC64? I’ve been working on developing patches for PowerPC64 but haven’t been completely successful. Most of the tests fail with SegFault. I would appreciate any advice or help.

Thanks in advance!

[redstar]

Yes, I am interested in this! Which LLVM version do you use? On Linux/PPC64, LLVM 4 does work and most of the test cases pass. With later LLVM versions most of the test cases crash. I did not yet find out what's wrong there. I suspect an LLVM regression with structs, but I am not sure about this.

[lenoil98]

Primarily I use LLVM 4. I’ve had some limited success with LLVM 6.

While the compiler (LDC2) is working, the issue I’m encountering seems to be with the runtime (druntime). I say this because segfaults occur when running apps that have been compiled with the compiler.

[valpackett]

• if you're on 12 or CURRENT, make sure your druntime is up to date for the 64-bit inode thing. Recently, my patch for using versioned symbols Link to 32-bit inode symbols on FreeBSD dlang/druntime#2668 was merged, make sure you have it. (Before, there was a local patch in Ports that migrated to the new structs)
• you might be interested in patches for using libexecinfo for backtraces, instead of the arch-specific custom unwinder: FreeBSD: switch to using external (libexecinfo) backtrace function like GDC does #3108
• are you working with the new openpower ELFv2 ABI or the old one?

[lenoil98]

Thanks!

I'm still using 11 as my development platform. Version 12 isn't quite stable on the older ELFv1 ABI hardware (Apple PM G5) that I'm using.

I'm using the llvmasm work-around someone had added for using in execinfo.d. Will give the new patches a try.

I'm not a professional programmer and don't know if I did things properly. I added PPC specific code in core/sys/freebsd/sys/elf_common.d and core/sys/posix/ucontext.d. I'm going to fork dlang/druntime and apply the patches I've developed, in hopes someone can double check my work.

[valpackett]

llvmasm work-around someone had added for using in execinfo.d

I did that for AArch64 :) before realizing that it's silly and GDC already successfully uses libexecinfo exclusively on FreeBSD, so LDC should do the same.

I added PPC specific code in core/sys/freebsd/sys/elf_common.d and core/sys/posix/ucontext.d

I've had to touch src/core/sys/posix/setjmp.d (dlang/druntime#2269)

[lenoil98]

The patches I made have been merged into (dlang/druntime#2683)

[lenoil98]

I've been able to build ldc-1.15 with the changes submitted (see previous comment). The test results are better than earlier results with 59% of the tests passing. Some test apps fail to build so many tests are not run. However of more serious concern are the tests where I get seg faults.

The the test results are at the link below:

https://drive.google.com/file/d/1A1PhW0592xqIKeI1KbcyUymNxuM_FwmT/view?usp=sharing.

[lenoil98]

This issue is OBE.