Change Details

This is a batch of fixes that allows FreeBSD/PowerPC64 use LLVM as themain compiler/linker. The commit list bellow refers to hashs found at LLVM Project repo https://github.com/llvm/llvm-project/tree/master, currently tagged as LLVM 9.X. The changes were backported to 8.x LLVM commit list: From 9529c563eb54e0937d6945e142a693d03b4b6893 Mon Sep 17 00:00:00 2001 From: Fangrui Song <maskray@google.com> Date: Fri, 10 May 2019 17:09:25 +0000 Subject: [PATCH] [MC][ELF] Copy top 3 bits of st_other to .symver aliases MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On PowerPC64 ELFv2 ABI, the top 3 bits of st_other encode the local entry offset. A versioned symbol alias created by .symver should copy the bits from the source symbol. This partly fixes PR41048. A full fix needs tracking of .set assignments and updating st_other fields when finish() is called, see D56586. Patch by Alfredo Dal'Ava Júnior Revision: https://reviews.llvm.org/D59436 llvm-svn: 360442 From 6cdd68e386d98c0535e9f977849f376e1e6f55a2 Mon Sep 17 00:00:00 2001 From: Fangrui Song <maskray@google.com> Date: Fri, 10 May 2019 05:51:00 +0000 Subject: [PATCH] [PPC64] Define getThunkSectionSpacing() based on the range of R_PPC64_REL24 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Suggested by Sean Fertile and Peter Smith. Thunk section spacing decrease the total number of thunks. I measured a decrease of 1% or less in some large programs, with no perceivable slowdown in link time. Override getThunkSectionSpacing() to enable it. 0x2000000 is the farthest point R_PPC64_REL24 can reach. I tried several numbers and found 0x2000000 works the best. Numbers near 0x2000000 work as well but let's just use the simpler number. As demonstrated by the updated tests, this essentially changes placement of most thunks to the end of the output section. We leverage this property to fix PR40740 reported by Alfredo Dal'Ava Júnior: The output section .init consists of input sections from several object files (crti.o crtbegin.o crtend.o crtn.o). Sections other than the last one do not have a terminator. With this patch, we create the thunk after the last .init input section and thus fix the issue. This is not foolproof but works quite well for such sections (with no terminator) in practice. Revision: https://reviews.llvm.org/D61720 llvm-svn: 360405 From 9efdd7ac5e914d3c9fa1ef33781acea43d98c913 Mon Sep 17 00:00:00 2001 From: Rui Ueyama <ruiu@google.com> Date: Fri, 15 Feb 2019 23:11:18 +0000 Subject: [PATCH] [PPC64] Preserve LocalEntry when linking On PowerPC64, it is necessary to keep the LocalEntry bits in st_other, especially when -r is used. Otherwise, when the resulting object is used in a posterior linking, LocalEntry info will be unavailable and functions may be called through the wrong entrypoint. Patch by Leandro Lupori. Revision: https://reviews.llvm.org/D56782 llvm-svn: 354184 From cd36a2857ea172d70a7a841f4b622a5f408944a9 Mon Sep 17 00:00:00 2001 From: Fangrui Song <maskray@google.com> Date: Tue, 21 May 2019 10:41:25 +0000 Subject: [PATCH] [PPC64] Update LocalEntry from assigned symbols On PowerPC64 ELFv2 ABI, functions may have 2 entry points: global and local. The local entry point location of a function is stored in the st_other field of the symbol, as an offset relative to the global entry point. In order to make symbol assignments (e.g. .equ/.set) work properly with this, PPCTargetELFStreamer already copies the local entry bits from the source symbol to the destination one, on emitAssignment(). The problem is that this copy is performed only at the assignment location, where the source symbol may not yet have processed the .localentry directive, that sets the local entry. This may cause the destination symbol to end up with wrong local entry information. Other symbol info is not affected by this because, in this case, the destination symbol value is actually a symbol reference. This change keeps track of these assignments, and update all needed st_other fields when finish() is called. Patch by Leandro Lupori! Revision: https://reviews.llvm.org/D56586 llvm-svn: 361237 From 61504079515f76ca094bb836c4d53b41064220d6 Mon Sep 17 00:00:00 2001 From: Fangrui Song <maskray@google.com> Date: Fri, 10 May 2019 16:24:57 +0000 Subject: [PATCH] [llvm-objdump] Print st_other Add support for ".hidden" ".internal" ".protected" and " 0x%02x" for other st_other bits used by some architectures. Revision: https://reviews.llvm.org/D61718 llvm-svn: 360439 From 44266b9e115ad172b1f6a88d15d4e7579812c0fc Mon Sep 17 00:00:00 2001 From: Martin Storsjo <martin@martin.st> Date: Thu, 16 May 2019 06:49:13 +0000 Subject: [PATCH] [PPC64][libunwind] Fix r2 not properly restored This change makes each unwind step inspect the instruction at the return address and, if needed, read r2 from its saved location and modify the context appropriately. The unwind logic is able to handle both ELFv1 and ELFv2 stacks. Reported by Bug 41050 Patch by Leandro Lupori! Revision: https://reviews.llvm.org/D59694 llvm-svn: 360861 From 905af40cc6ce0d246e42bf7db456d8ca944caaf6 Mon Sep 17 00:00:00 2001 From: Martin Storsjo <martin@martin.st> Date: Thu, 16 May 2019 06:49:20 +0000 Subject: [PATCH] [PPC] Fix 32-bit build of libunwind Clang integrated assembler was unable to build libunwind PPC32 assembly code, present in functions used to save/restore register context. This change consists in replacing the assembly style used in libunwind source, to one that is compatible with both Clang integrated assembler as well as GNU assembler. Patch by Leandro Lupori! Revision: https://reviews.llvm.org/D61792 llvm-svn: 360862 From 1c61471ab1cba735f57824ec8a38db845e60ab84 From: Fangrui Song <maskray@google.com> Date: Wed May 22 07:29:59 2019 +0000 [PPC64] Parse -elfv1 -elfv2 when specified on target triple Summary: For big-endian powerpc64, the default ABI is ELFv1. OpenPower ABI ELFv2 is supported when -mabi=elfv2 is specified. FreeBSD support for PowerPC64 ELFv2 ABI with LLVM is in progress[1]. This patch adds an alternative way to specify ELFv2 ABI on target triple [2]. The following results are expected: ELFv1 when using: -target powerpc64-unknown-freebsd12.0 -target powerpc64-unknown-freebsd12.0 -mabi=elfv1 -target powerpc64-unknown-freebsd12.0-elfv1 ELFv2 when using: -target powerpc64-unknown-freebsd12.0 -mabi=elfv2 -target powerpc64-unknown-freebsd12.0-elfv2 [1] https://wiki.freebsd.org/powerpc/llvm-elfv2 [2] https://clang.llvm.org/docs/CrossCompilation.html Patch by Alfredo Dal'Ava J<C3><BA>nior! Revision: https://reviews.llvm.org/D61950 llvm-svn: 361355

This is a fixe that allows FreeBSD/PowerPC64 use LLVM as themain compiler/linker. The commit list bellow refers to hashs found at LLVM Project repo https://github.com/llvm/llvm-project/tree/master, currently tagged as LLVM 9.X. The changes were backported to 8.x LLVM commit list: From 44266b9e115ad172b1f6a88d15d4e7579812c0fc Mon Sep 17 00:00:00 2001 From: Martin Storsjo <martin@martin.st> Date: Thu, 16 May 2019 06:49:13 +0000 Subject: [PATCH] [PPC64][libunwind] Fix r2 not properly restored This change makes each unwind step inspect the instruction at the return address and, if needed, read r2 from its saved location and modify the context appropriately. The unwind logic is able to handle both ELFv1 and ELFv2 stacks. Reported by Bug 41050 Patch by Leandro Lupori! Revision: https://reviews.llvm.org/D59694 llvm-svn: 360861

This is a batch of fixes that allows FreeBSD/PowerPC64 use LLVM as themain compiler/linker. The commit list bellow refers to hashs found at LLVM Project repo https://github.com/llvm/llvm-project/tree/master, currently tagged as LLVM 9.X. The changes were backported to 8.x LLVM commit list: From 9529c563eb54e0937d6945e142a693d03b4b6893 Mon Sep 17 00:00:00 2001 From: Fangrui Song <maskray@google.com> Date: Fri, 10 May 2019 17:09:25 +0000 Subject: [PATCH] [MC][ELF] Copy top 3 bits of st_other to .symver aliases MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On PowerPC64 ELFv2 ABI, the top 3 bits of st_other encode the local entry offset. A versioned symbol alias created by .symver should copy the bits from the source symbol. This partly fixes PR41048. A full fix needs tracking of .set assignments and updating st_other fields when finish() is called, see D56586. Patch by Alfredo Dal'Ava Júnior Revision: https://reviews.llvm.org/D59436 llvm-svn: 360442 From 6cdd68e386d98c0535e9f977849f376e1e6f55a2 Mon Sep 17 00:00:00 2001 From: Fangrui Song <maskray@google.com> Date: Fri, 10 May 2019 05:51:00 +0000 Subject: [PATCH] [PPC64] Define getThunkSectionSpacing() based on the range of R_PPC64_REL24 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Suggested by Sean Fertile and Peter Smith. Thunk section spacing decrease the total number of thunks. I measured a decrease of 1% or less in some large programs, with no perceivable slowdown in link time. Override getThunkSectionSpacing() to enable it. 0x2000000 is the farthest point R_PPC64_REL24 can reach. I tried several numbers and found 0x2000000 works the best. Numbers near 0x2000000 work as well but let's just use the simpler number. As demonstrated by the updated tests, this essentially changes placement of most thunks to the end of the output section. We leverage this property to fix PR40740 reported by Alfredo Dal'Ava Júnior: The output section .init consists of input sections from several object files (crti.o crtbegin.o crtend.o crtn.o). Sections other than the last one do not have a terminator. With this patch, we create the thunk after the last .init input section and thus fix the issue. This is not foolproof but works quite well for such sections (with no terminator) in practice. Revision: https://reviews.llvm.org/D61720 llvm-svn: 360405 From 9efdd7ac5e914d3c9fa1ef33781acea43d98c913 Mon Sep 17 00:00:00 2001 From: Rui Ueyama <ruiu@google.com> Date: Fri, 15 Feb 2019 23:11:18 +0000 Subject: [PATCH] [PPC64] Preserve LocalEntry when linking On PowerPC64, it is necessary to keep the LocalEntry bits in st_other, especially when -r is used. Otherwise, when the resulting object is used in a posterior linking, LocalEntry info will be unavailable and functions may be called through the wrong entrypoint. Patch by Leandro Lupori. Revision: https://reviews.llvm.org/D56782 llvm-svn: 354184 From cd36a2857ea172d70a7a841f4b622a5f408944a9 Mon Sep 17 00:00:00 2001 From: Fangrui Song <maskray@google.com> Date: Tue, 21 May 2019 10:41:25 +0000 Subject: [PATCH] [PPC64] Update LocalEntry from assigned symbols On PowerPC64 ELFv2 ABI, functions may have 2 entry points: global and local. The local entry point location of a function is stored in the st_other field of the symbol, as an offset relative to the global entry point. In order to make symbol assignments (e.g. .equ/.set) work properly with this, PPCTargetELFStreamer already copies the local entry bits from the source symbol to the destination one, on emitAssignment(). The problem is that this copy is performed only at the assignment location, where the source symbol may not yet have processed the .localentry directive, that sets the local entry. This may cause the destination symbol to end up with wrong local entry information. Other symbol info is not affected by this because, in this case, the destination symbol value is actually a symbol reference. This change keeps track of these assignments, and update all needed st_other fields when finish() is called. Patch by Leandro Lupori! Revision: https://reviews.llvm.org/D56586 llvm-svn: 361237 From 61504079515f76ca094bb836c4d53b41064220d6 Mon Sep 17 00:00:00 2001 From: Fangrui Song <maskray@google.com> Date: Fri, 10 May 2019 16:24:57 +0000 Subject: [PATCH] [llvm-objdump] Print st_other Add support for ".hidden" ".internal" ".protected" and " 0x%02x" for other st_other bits used by some architectures. Revision: https://reviews.llvm.org/D61718 llvm-svn: 360439 From 44266b9e115ad172b1f6a88d15d4e7579812c0fc Mon Sep 17 00:00:00 2001 From: Martin Storsjo <martin@martin.st> Date: Thu, 16 May 2019 06:49:13 +0000 Subject: [PATCH] [PPC64][libunwind] Fix r2 not properly restored This change makes each unwind step inspect the instruction at the return address and, if needed, read r2 from its saved location and modify the context appropriately. The unwind logic is able to handle both ELFv1 and ELFv2 stacks. Reported by Bug 41050 Patch by Leandro Lupori! Revision: https://reviews.llvm.org/D59694 llvm-svn: 360861 From 905af40cc6ce0d246e42bf7db456d8ca944caaf6 Mon Sep 17 00:00:00 2001 From: Martin Storsjo <martin@martin.st> Date: Thu, 16 May 2019 06:49:20 +0000 Subject: [PATCH] [PPC] Fix 32-bit build of libunwind Clang integrated assembler was unable to build libunwind PPC32 assembly code, present in functions used to save/restore register context. This change consists in replacing the assembly style used in libunwind source, to one that is compatible with both Clang integrated assembler as well as GNU assembler. Patch by Leandro Lupori! Revision: https://reviews.llvm.org/D61792 llvm-svn: 360862 From 1c61471ab1cba735f57824ec8a38db845e60ab84 From: Fangrui Song <maskray@google.com> Date: Wed May 22 07:29:59 2019 +0000 [PPC64] Parse -elfv1 -elfv2 when specified on target triple Summary: For big-endian powerpc64, the default ABI is ELFv1. OpenPower ABI ELFv2 is supported when -mabi=elfv2 is specified. FreeBSD support for PowerPC64 ELFv2 ABI with LLVM is in progress[1]. This patch adds an alternative way to specify ELFv2 ABI on target triple [2]. The following results are expected: ELFv1 when using: -target powerpc64-unknown-freebsd12.0 -target powerpc64-unknown-freebsd12.0 -mabi=elfv1 -target powerpc64-unknown-freebsd12.0-elfv1 ELFv2 when using: -target powerpc64-unknown-freebsd12.0 -mabi=elfv2 -target powerpc64-unknown-freebsd12.0-elfv2 [1] https://wiki.freebsd.org/powerpc/llvm-elfv2 [2] https://clang.llvm.org/docs/CrossCompilation.html Patch by Alfredo Dal'Ava J<C3><BA>nior! Revision: https://reviews.llvm.org/D61950 llvm-svn: 361355