From: "Kirill A. Korinsky" Subject: llvm/sparc64: match BFD -N alignment To: Sebastien Marie , Robert Nagy Cc: OpenBSD tech Date: Tue, 18 Aug 2026 15:18:01 +0200 Robert, Sebastien, BFD aligns nonpaged PT_LOAD segments to their maximum contained section alignment. Do the same for SPARCV9 instead of retaining the 1 MiB maximum page alignment. This removes roughly 1 MiB of leading padding from ofwboot without changing its load address or memory layout. Here diff for the base and llvm/22 in ports. Ok? Index: src/gnu/llvm/lld/ELF/Driver.cpp =================================================================== RCS file: /home/cvs/src/gnu/llvm/lld/ELF/Driver.cpp,v diff -u -p -r1.25 Driver.cpp --- src/gnu/llvm/lld/ELF/Driver.cpp 30 Jul 2026 19:28:37 -0000 1.25 +++ src/gnu/llvm/lld/ELF/Driver.cpp 18 Aug 2026 13:01:23 -0000 @@ -3496,6 +3496,12 @@ template void LinkerDriver: // sections are non-aligned (maxPageSize set to 1) but text sections are aligned // to the target page size. ctx.arg.textAlignPageSize = ctx.arg.omagic ? getRealMaxPageSize(ctx, args) : ctx.arg.maxPageSize; +#ifdef __OpenBSD__ + // Match BFD -N semantics for SPARCV9: use the maximum contained section + // alignment for PT_LOAD segments instead of the 1 MiB page alignment. + if (ctx.arg.omagic && ctx.arg.emachine == EM_SPARCV9) + ctx.arg.textAlignPageSize = ctx.arg.maxPageSize; +#endif ctx.arg.imageBase = getImageBase(ctx, args); Index: src/gnu/llvm/lld/ELF/Writer.cpp =================================================================== RCS file: /home/cvs/src/gnu/llvm/lld/ELF/Writer.cpp,v diff -u -p -r1.11 Writer.cpp --- src/gnu/llvm/lld/ELF/Writer.cpp 30 Jul 2026 19:28:37 -0000 1.11 +++ src/gnu/llvm/lld/ELF/Writer.cpp 18 Aug 2026 13:01:23 -0000 @@ -2701,6 +2701,16 @@ template void Writer: ctx.out.programHeaders->offset = ctx.out.elfHeader->size; uint64_t off = ctx.out.elfHeader->size + ctx.out.programHeaders->size; +#ifdef __OpenBSD__ + // BFD's implicit script reserves 0x200 bytes before fixed-address SPARCV9 + // -N payloads consumed by OpenFirmware. + if (!ctx.arg.relocatable && ctx.arg.omagic && + ctx.arg.emachine == EM_SPARCV9 && + ctx.arg.sectionStartMap.count(".text") && + !ctx.script->hasSectionsCommand && !ctx.script->hasPhdrsCommands()) + off = std::max(off, 0x200); +#endif + PhdrEntry *lastRX = nullptr; for (Partition &part : ctx.partitions) for (auto &p : part.phdrs) Index: ports/devel/llvm/22/Makefile =================================================================== RCS file: /home/cvs/ports/devel/llvm/22/Makefile,v diff -u -p -r1.22 Makefile --- ports/devel/llvm/22/Makefile 30 Jul 2026 19:28:03 -0000 1.22 +++ ports/devel/llvm/22/Makefile 18 Aug 2026 13:17:33 -0000 @@ -2,7 +2,7 @@ LLVM_MAJOR = 22 LLVM_VERSION = ${LLVM_MAJOR}.1.8 LLVM_PKGSPEC = >=22,<23 -REVISION = 4 +REVISION = 5 SHARED_LIBS += LLVM 0.0 \ LTO 0.0 \ Index: ports/devel/llvm/22/patches/patch-lld_ELF_Driver_cpp =================================================================== RCS file: /home/cvs/ports/devel/llvm/22/patches/patch-lld_ELF_Driver_cpp,v diff -u -p -r1.3 patch-lld_ELF_Driver_cpp --- ports/devel/llvm/22/patches/patch-lld_ELF_Driver_cpp 30 Jul 2026 19:28:03 -0000 1.3 +++ ports/devel/llvm/22/patches/patch-lld_ELF_Driver_cpp 18 Aug 2026 13:14:56 -0000 @@ -169,7 +169,7 @@ Index: lld/ELF/Driver.cpp // Parses --image-base option. static std::optional getImageBase(Ctx &ctx, opt::InputArgList &args) { // Because we are using `ctx.arg.maxPageSize` here, this function has to be -@@ -3435,6 +3491,11 @@ template void LinkerDriver::link(opt::Inp +@@ -3435,6 +3491,17 @@ template void LinkerDriver::link(opt::Inp // optimizations such as DATA_SEGMENT_ALIGN in linker scripts. LLD's use of it // is limited to writing trap instructions on the last executable segment. ctx.arg.commonPageSize = getCommonPageSize(ctx, args); @@ -178,6 +178,12 @@ Index: lld/ELF/Driver.cpp + // sections are non-aligned (maxPageSize set to 1) but text sections are aligned + // to the target page size. + ctx.arg.textAlignPageSize = ctx.arg.omagic ? getRealMaxPageSize(ctx, args) : ctx.arg.maxPageSize; ++#ifdef __OpenBSD__ ++ // Match BFD -N semantics for SPARCV9: use the maximum contained section ++ // alignment for PT_LOAD segments instead of the 1 MiB page alignment. ++ if (ctx.arg.omagic && ctx.arg.emachine == EM_SPARCV9) ++ ctx.arg.textAlignPageSize = ctx.arg.maxPageSize; ++#endif ctx.arg.imageBase = getImageBase(ctx, args); Index: ports/devel/llvm/22/patches/patch-lld_ELF_Writer_cpp =================================================================== RCS file: /home/cvs/ports/devel/llvm/22/patches/patch-lld_ELF_Writer_cpp,v diff -u -p -r1.2 patch-lld_ELF_Writer_cpp --- ports/devel/llvm/22/patches/patch-lld_ELF_Writer_cpp 30 Jul 2026 19:28:03 -0000 1.2 +++ ports/devel/llvm/22/patches/patch-lld_ELF_Writer_cpp 18 Aug 2026 13:14:56 -0000 @@ -183,11 +183,10 @@ Index: lld/ELF/Writer.cpp if (OutputSection *cmd = findSection(ctx, ".note.gnu.property", partNo)) addHdr(PT_GNU_PROPERTY, PF_R)->add(cmd); -@@ -2586,6 +2610,31 @@ template void Writer::fixSectionAli - }; +@@ -2587,6 +2611,31 @@ template void Writer::fixSectionAli } }; -+ + +#ifndef __OpenBSD__ + // On i386, produce binaries that are compatible with our W^X implementation + if (ctx.arg.emachine == EM_386) { @@ -212,6 +211,24 @@ Index: lld/ELF/Writer.cpp + } + } +#endif - ++ for (Partition &part : ctx.partitions) { prev = nullptr; + for (auto &p : part.phdrs) +@@ -2651,6 +2700,16 @@ static std::string rangeToString(uint64_t addr, uint64 + template void Writer::assignFileOffsets() { + ctx.out.programHeaders->offset = ctx.out.elfHeader->size; + uint64_t off = ctx.out.elfHeader->size + ctx.out.programHeaders->size; ++ ++#ifdef __OpenBSD__ ++ // BFD's implicit script reserves 0x200 bytes before fixed-address SPARCV9 ++ // -N payloads consumed by OpenFirmware. ++ if (!ctx.arg.relocatable && ctx.arg.omagic && ++ ctx.arg.emachine == EM_SPARCV9 && ++ ctx.arg.sectionStartMap.count(".text") && ++ !ctx.script->hasSectionsCommand && !ctx.script->hasPhdrsCommands()) ++ off = std::max(off, 0x200); ++#endif + + PhdrEntry *lastRX = nullptr; + for (Partition &part : ctx.partitions) -- wbr, Kirill