Re: Status of clang-llvm builds? Related to powerpc-spe.
On Sat, Jan 23, 2021, 3:36 AM Hesham Almatary wrote: > On Fri, 22 Jan 2021 at 21:30, wrote: > > > > Actually, replying to myself: > > > > I bet the context-switching code is broken for platforms that use the > SPE via a Freescale library. That's something I'll need to look at. > > > > > On Jan 22, 2021, at 14:26 , Peter Dufault wrote: > > > > > > Signed PGP part > > > The PowerPC Signal Processing Engine (powerpc-spe) is now gone from > gcc and therefore from RTEMS (on the master branch). It *appears* to be > supported with Clang/LLVM on FreeBSD, apparently primarily to support some > Amiga platforms (I think), I think it's supported beginning in FreeBSD 12. > > > > > > RTEMS has appropriately pulled out support for the SPE. Since in the > applications I use the SPE is used via libraries from > Motorola/Freescale/... that may be OK, but having support for the > architecture would "look good" to my clients. > > > > > > I'm not going to push for a project to switch to LLVM for the SPE > targets, I don't have either the time or the money and I'm not going to ask > my clients to fund it. But I do want to know: > > > > > > - What's the status of Clang/LLVM and RTEMS? Is it production-ready > and production-used on certain (RISCV?) platforms? > > I don't think so (at least for RISC-V). Currently, it relies on users > knowing how to build and teach LLVM about other externally-built libs > such as newlib and compiler-rt (libgcc). Also, I had to add an RTEMS > driver [1] to the backend and that's not upstream AFAIR. > We will need to teach RSB to build all of that (currently it has a > target for LLVM), newlib, compiler-rt and install a sysroot and a > config file that includes paths to the installed libs. Additionally, > to get C++ support, the relative libs will also need to be built > manually/separately. > Is this any better with the sparc? Gaisler did work for ESA to support llvm and I think they are shipping llvm with their RCC package. > > [1] > https://github.com/CTSRD-CHERI/llvm-project/blob/master/clang/lib/Driver/ToolChains/RTEMS.cpp > > > > > > - Does anybody know anything the quality of the "powerpc-spe" support > in Clang/LLVM? > > > > > > This is must an exploratory question. I don't have a plan to work on > this soon. > > > > > > Peter > > > - > > > Peter Dufault > > > HD Associates, Inc. Software and System Engineering > > > > > > This email is delivered through the public internet using protocols > subject to interception and tampering. > > > > > > > > > > > > > Peter > > - > > Peter Dufault > > HD Associates, Inc. Software and System Engineering > > > > This email is delivered through the public internet using protocols > subject to interception and tampering. > > > > ___ > > devel mailing list > > devel@rtems.org > > http://lists.rtems.org/mailman/listinfo/devel > ___ > devel mailing list > devel@rtems.org > http://lists.rtems.org/mailman/listinfo/devel > ___ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
Re: Status of clang-llvm builds? Related to powerpc-spe.
On Fri, 22 Jan 2021 at 21:30, wrote: > > Actually, replying to myself: > > I bet the context-switching code is broken for platforms that use the SPE via > a Freescale library. That's something I'll need to look at. > > > On Jan 22, 2021, at 14:26 , Peter Dufault wrote: > > > > Signed PGP part > > The PowerPC Signal Processing Engine (powerpc-spe) is now gone from gcc and > > therefore from RTEMS (on the master branch). It *appears* to be supported > > with Clang/LLVM on FreeBSD, apparently primarily to support some Amiga > > platforms (I think), I think it's supported beginning in FreeBSD 12. > > > > RTEMS has appropriately pulled out support for the SPE. Since in the > > applications I use the SPE is used via libraries from > > Motorola/Freescale/... that may be OK, but having support for the > > architecture would "look good" to my clients. > > > > I'm not going to push for a project to switch to LLVM for the SPE targets, > > I don't have either the time or the money and I'm not going to ask my > > clients to fund it. But I do want to know: > > > > - What's the status of Clang/LLVM and RTEMS? Is it production-ready and > > production-used on certain (RISCV?) platforms? I don't think so (at least for RISC-V). Currently, it relies on users knowing how to build and teach LLVM about other externally-built libs such as newlib and compiler-rt (libgcc). Also, I had to add an RTEMS driver [1] to the backend and that's not upstream AFAIR. We will need to teach RSB to build all of that (currently it has a target for LLVM), newlib, compiler-rt and install a sysroot and a config file that includes paths to the installed libs. Additionally, to get C++ support, the relative libs will also need to be built manually/separately. [1] https://github.com/CTSRD-CHERI/llvm-project/blob/master/clang/lib/Driver/ToolChains/RTEMS.cpp > > > - Does anybody know anything the quality of the "powerpc-spe" support in > > Clang/LLVM? > > > > This is must an exploratory question. I don't have a plan to work on this > > soon. > > > > Peter > > - > > Peter Dufault > > HD Associates, Inc. Software and System Engineering > > > > This email is delivered through the public internet using protocols subject > > to interception and tampering. > > > > > > > > Peter > - > Peter Dufault > HD Associates, Inc. Software and System Engineering > > This email is delivered through the public internet using protocols subject > to interception and tampering. > > ___ > devel mailing list > devel@rtems.org > http://lists.rtems.org/mailman/listinfo/devel ___ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
Re: Status of clang-llvm builds? Related to powerpc-spe.
Actually, replying to myself: I bet the context-switching code is broken for platforms that use the SPE via a Freescale library. That's something I'll need to look at. > On Jan 22, 2021, at 14:26 , Peter Dufault wrote: > > Signed PGP part > The PowerPC Signal Processing Engine (powerpc-spe) is now gone from gcc and > therefore from RTEMS (on the master branch). It *appears* to be supported > with Clang/LLVM on FreeBSD, apparently primarily to support some Amiga > platforms (I think), I think it's supported beginning in FreeBSD 12. > > RTEMS has appropriately pulled out support for the SPE. Since in the > applications I use the SPE is used via libraries from Motorola/Freescale/... > that may be OK, but having support for the architecture would "look good" to > my clients. > > I'm not going to push for a project to switch to LLVM for the SPE targets, I > don't have either the time or the money and I'm not going to ask my clients > to fund it. But I do want to know: > > - What's the status of Clang/LLVM and RTEMS? Is it production-ready and > production-used on certain (RISCV?) platforms? > - Does anybody know anything the quality of the "powerpc-spe" support in > Clang/LLVM? > > This is must an exploratory question. I don't have a plan to work on this > soon. > > Peter > - > Peter Dufault > HD Associates, Inc. Software and System Engineering > > This email is delivered through the public internet using protocols subject > to interception and tampering. > > > Peter - Peter Dufault HD Associates, Inc. Software and System Engineering This email is delivered through the public internet using protocols subject to interception and tampering. signature.asc Description: Message signed with OpenPGP ___ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
