Date: Fri, 3 Jan 2020 20:11:40 +0000 (UTC) From: Dimitry Andric <dim@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r356330 - head/contrib/llvm-project/llvm/lib/Target/RISCV Message-ID: <202001032011.003KBeJr093187@repo.freebsd.org>
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Author: dim Date: Fri Jan 3 20:11:40 2020 New Revision: 356330 URL: https://svnweb.freebsd.org/changeset/base/356330 Log: Merge commit da7b129b1 from llvm git (by James Clarke): [RISCV] Don't force Local Exec TLS for non-PIC Summary: Forcing Local Exec TLS requires the use of copy relocations. Copy relocations need special handling in the runtime linker when being used against TLS symbols, which is present in glibc, but not in FreeBSD nor musl, and so cannot be relied upon. Moreover, copy relocations are a hack that embed the size of an object in the ABI when it otherwise wouldn't be, and break protected symbols (which are expected to be DSO local), whilst also wasting space, thus they should be avoided whenever possible. As discussed in D70398, RISC-V should move away from forcing Local Exec, and instead use Initial Exec like other targets, with possible linker relaxation to follow. The RISC-V GCC maintainers also intend to adopt this more-conventional behaviour (see https://github.com/riscv/riscv-elf-psabi-doc/issues/122). Reviewers: asb, MaskRay Reviewed By: MaskRay Subscribers: emaste, krytarowski, hiraditya, rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, llvm-commits, bsdjhb Tags: #llvm Differential Revision: https://reviews.llvm.org/D70649 This is a prerequisite for building and linking hard- and soft-float riscv worlds with clang and lld. Requested by: jhb MFC after: 1 week X-MFC-With: r353358 Modified: head/contrib/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp Modified: head/contrib/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp ============================================================================== --- head/contrib/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp Fri Jan 3 20:09:38 2020 (r356329) +++ head/contrib/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp Fri Jan 3 20:11:40 2020 (r356330) @@ -570,10 +570,7 @@ SDValue RISCVTargetLowering::lowerGlobalTLSAddress(SDV int64_t Offset = N->getOffset(); MVT XLenVT = Subtarget.getXLenVT(); - // Non-PIC TLS lowering should always use the LocalExec model. - TLSModel::Model Model = isPositionIndependent() - ? getTargetMachine().getTLSModel(N->getGlobal()) - : TLSModel::LocalExec; + TLSModel::Model Model = getTargetMachine().getTLSModel(N->getGlobal()); SDValue Addr; switch (Model) {
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