| // Inferno utils/5l/asm.c |
| // https://bitbucket.org/inferno-os/inferno-os/src/master/utils/5l/asm.c |
| // |
| // Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved. |
| // Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net) |
| // Portions Copyright © 1997-1999 Vita Nuova Limited |
| // Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com) |
| // Portions Copyright © 2004,2006 Bruce Ellis |
| // Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net) |
| // Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others |
| // Portions Copyright © 2009 The Go Authors. All rights reserved. |
| // |
| // Permission is hereby granted, free of charge, to any person obtaining a copy |
| // of this software and associated documentation files (the "Software"), to deal |
| // in the Software without restriction, including without limitation the rights |
| // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| // copies of the Software, and to permit persons to whom the Software is |
| // furnished to do so, subject to the following conditions: |
| // |
| // The above copyright notice and this permission notice shall be included in |
| // all copies or substantial portions of the Software. |
| // |
| // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| // THE SOFTWARE. |
| |
| package s390x |
| |
| import ( |
| "cmd/internal/objabi" |
| "cmd/internal/sys" |
| "cmd/link/internal/ld" |
| "cmd/link/internal/loader" |
| "cmd/link/internal/sym" |
| "debug/elf" |
| "log" |
| ) |
| |
| // gentext generates assembly to append the local moduledata to the global |
| // moduledata linked list at initialization time. This is only done if the runtime |
| // is in a different module. |
| // |
| // <go.link.addmoduledata>: |
| // larl %r2, <local.moduledata> |
| // jg <runtime.addmoduledata@plt> |
| // undef |
| // |
| // The job of appending the moduledata is delegated to runtime.addmoduledata. |
| func gentext(ctxt *ld.Link, ldr *loader.Loader) { |
| initfunc, addmoduledata := ld.PrepareAddmoduledata(ctxt) |
| if initfunc == nil { |
| return |
| } |
| |
| // larl %r2, <local.moduledata> |
| initfunc.AddUint8(0xc0) |
| initfunc.AddUint8(0x20) |
| initfunc.AddSymRef(ctxt.Arch, ctxt.Moduledata, 6, objabi.R_PCREL, 4) |
| r1 := initfunc.Relocs() |
| ldr.SetRelocVariant(initfunc.Sym(), r1.Count()-1, sym.RV_390_DBL) |
| |
| // jg <runtime.addmoduledata[@plt]> |
| initfunc.AddUint8(0xc0) |
| initfunc.AddUint8(0xf4) |
| initfunc.AddSymRef(ctxt.Arch, addmoduledata, 6, objabi.R_CALL, 4) |
| r2 := initfunc.Relocs() |
| ldr.SetRelocVariant(initfunc.Sym(), r2.Count()-1, sym.RV_390_DBL) |
| |
| // undef (for debugging) |
| initfunc.AddUint32(ctxt.Arch, 0) |
| } |
| |
| func adddynrel(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s loader.Sym, r loader.Reloc, rIdx int) bool { |
| targ := r.Sym() |
| var targType sym.SymKind |
| if targ != 0 { |
| targType = ldr.SymType(targ) |
| } |
| |
| switch r.Type() { |
| default: |
| if r.Type() >= objabi.ElfRelocOffset { |
| ldr.Errorf(s, "unexpected relocation type %d", r.Type()) |
| return false |
| } |
| |
| // Handle relocations found in ELF object files. |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_12), |
| objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_GOT12): |
| ldr.Errorf(s, "s390x 12-bit relocations have not been implemented (relocation type %d)", r.Type()-objabi.ElfRelocOffset) |
| return false |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_8), |
| objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_16), |
| objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_32), |
| objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_64): |
| if targType == sym.SDYNIMPORT { |
| ldr.Errorf(s, "unexpected R_390_nn relocation for dynamic symbol %s", ldr.SymName(targ)) |
| } |
| su := ldr.MakeSymbolUpdater(s) |
| su.SetRelocType(rIdx, objabi.R_ADDR) |
| if target.IsPIE() && target.IsInternal() { |
| // For internal linking PIE, this R_ADDR relocation cannot |
| // be resolved statically. We need to generate a dynamic |
| // relocation. Let the code below handle it. |
| break |
| } |
| return true |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_PC16), |
| objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_PC32), |
| objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_PC64): |
| if targType == sym.SDYNIMPORT { |
| ldr.Errorf(s, "unexpected R_390_PCnn relocation for dynamic symbol %s", ldr.SymName(targ)) |
| } |
| if targType == 0 || targType == sym.SXREF { |
| ldr.Errorf(s, "unknown symbol %s in pcrel", ldr.SymName(targ)) |
| } |
| su := ldr.MakeSymbolUpdater(s) |
| su.SetRelocType(rIdx, objabi.R_PCREL) |
| su.SetRelocAdd(rIdx, r.Add()+int64(r.Siz())) |
| return true |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_GOT16), |
| objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_GOT32), |
| objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_GOT64): |
| ldr.Errorf(s, "unimplemented S390x relocation: %v", r.Type()-objabi.ElfRelocOffset) |
| return true |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_PLT16DBL), |
| objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_PLT32DBL): |
| su := ldr.MakeSymbolUpdater(s) |
| su.SetRelocType(rIdx, objabi.R_PCREL) |
| ldr.SetRelocVariant(s, rIdx, sym.RV_390_DBL) |
| su.SetRelocAdd(rIdx, r.Add()+int64(r.Siz())) |
| if targType == sym.SDYNIMPORT { |
| addpltsym(target, ldr, syms, targ) |
| r.SetSym(syms.PLT) |
| su.SetRelocAdd(rIdx, r.Add()+int64(ldr.SymPlt(targ))) |
| } |
| return true |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_PLT32), |
| objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_PLT64): |
| su := ldr.MakeSymbolUpdater(s) |
| su.SetRelocType(rIdx, objabi.R_PCREL) |
| su.SetRelocAdd(rIdx, r.Add()+int64(r.Siz())) |
| if targType == sym.SDYNIMPORT { |
| addpltsym(target, ldr, syms, targ) |
| r.SetSym(syms.PLT) |
| su.SetRelocAdd(rIdx, r.Add()+int64(ldr.SymPlt(targ))) |
| } |
| return true |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_COPY): |
| ldr.Errorf(s, "unimplemented S390x relocation: %v", r.Type()-objabi.ElfRelocOffset) |
| return false |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_GLOB_DAT): |
| ldr.Errorf(s, "unimplemented S390x relocation: %v", r.Type()-objabi.ElfRelocOffset) |
| return false |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_JMP_SLOT): |
| ldr.Errorf(s, "unimplemented S390x relocation: %v", r.Type()-objabi.ElfRelocOffset) |
| return false |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_RELATIVE): |
| ldr.Errorf(s, "unimplemented S390x relocation: %v", r.Type()-objabi.ElfRelocOffset) |
| return false |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_GOTOFF): |
| if targType == sym.SDYNIMPORT { |
| ldr.Errorf(s, "unexpected R_390_GOTOFF relocation for dynamic symbol %s", ldr.SymName(targ)) |
| } |
| su := ldr.MakeSymbolUpdater(s) |
| su.SetRelocType(rIdx, objabi.R_GOTOFF) |
| return true |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_GOTPC): |
| su := ldr.MakeSymbolUpdater(s) |
| su.SetRelocType(rIdx, objabi.R_PCREL) |
| r.SetSym(syms.GOT) |
| su.SetRelocAdd(rIdx, r.Add()+int64(r.Siz())) |
| return true |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_PC16DBL), |
| objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_PC32DBL): |
| su := ldr.MakeSymbolUpdater(s) |
| su.SetRelocType(rIdx, objabi.R_PCREL) |
| ldr.SetRelocVariant(s, rIdx, sym.RV_390_DBL) |
| su.SetRelocAdd(rIdx, r.Add()+int64(r.Siz())) |
| if targType == sym.SDYNIMPORT { |
| ldr.Errorf(s, "unexpected R_390_PCnnDBL relocation for dynamic symbol %s", ldr.SymName(targ)) |
| } |
| return true |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_GOTPCDBL): |
| su := ldr.MakeSymbolUpdater(s) |
| su.SetRelocType(rIdx, objabi.R_PCREL) |
| ldr.SetRelocVariant(s, rIdx, sym.RV_390_DBL) |
| r.SetSym(syms.GOT) |
| su.SetRelocAdd(rIdx, r.Add()+int64(r.Siz())) |
| return true |
| |
| case objabi.ElfRelocOffset + objabi.RelocType(elf.R_390_GOTENT): |
| ld.AddGotSym(target, ldr, syms, targ, uint32(elf.R_390_GLOB_DAT)) |
| su := ldr.MakeSymbolUpdater(s) |
| su.SetRelocType(rIdx, objabi.R_PCREL) |
| ldr.SetRelocVariant(s, rIdx, sym.RV_390_DBL) |
| r.SetSym(syms.GOT) |
| su.SetRelocAdd(rIdx, r.Add()+int64(ldr.SymGot(targ))+int64(r.Siz())) |
| return true |
| } |
| |
| // Reread the reloc to incorporate any changes in type above. |
| relocs := ldr.Relocs(s) |
| r = relocs.At(rIdx) |
| |
| switch r.Type() { |
| case objabi.R_CALL, objabi.R_PCRELDBL: |
| if targType != sym.SDYNIMPORT { |
| // nothing to do, the relocation will be laid out in reloc |
| return true |
| } |
| if target.IsExternal() { |
| // External linker will do this relocation. |
| return true |
| } |
| // Internal linking: build a PLT entry and redirect to it. |
| addpltsym(target, ldr, syms, targ) |
| su := ldr.MakeSymbolUpdater(s) |
| su.SetRelocSym(rIdx, syms.PLT) |
| su.SetRelocAdd(rIdx, r.Add()+int64(ldr.SymPlt(targ))) |
| return true |
| |
| case objabi.R_ADDR: |
| if ldr.SymType(s).IsText() && target.IsElf() { |
| // The code is asking for the address of an external |
| // function. We provide it with the address of the |
| // correspondent GOT symbol. |
| ld.AddGotSym(target, ldr, syms, targ, uint32(elf.R_390_GLOB_DAT)) |
| su := ldr.MakeSymbolUpdater(s) |
| su.SetRelocSym(rIdx, syms.GOT) |
| su.SetRelocAdd(rIdx, r.Add()+int64(ldr.SymGot(targ))) |
| return true |
| } |
| |
| // Process dynamic relocations for the data sections. |
| if target.IsPIE() && target.IsInternal() { |
| // When internally linking, generate dynamic relocations |
| // for all typical R_ADDR relocations. The exception |
| // are those R_ADDR that are created as part of generating |
| // the dynamic relocations and must be resolved statically. |
| // |
| // These synthetic static R_ADDR relocs must be skipped |
| // now, or else we will be caught in an infinite loop |
| // of generating synthetic relocs for our synthetic |
| // relocs. |
| switch ldr.SymName(s) { |
| case ".dynsym", ".rela", ".rela.plt", ".got.plt", ".dynamic": |
| return false |
| } |
| } else { |
| // Either internally linking a static executable, |
| // in which case we can resolve these relocations |
| // statically in the 'reloc' phase, or externally |
| // linking, in which case the relocation will be |
| // prepared in the 'reloc' phase and passed to the |
| // external linker in the 'asmb' phase. |
| if t := ldr.SymType(s); !t.IsDATA() && !t.IsRODATA() { |
| break |
| } |
| } |
| |
| if target.IsElf() { |
| // Generate R_390_RELATIVE relocations for best |
| // efficiency in the dynamic linker. |
| // |
| // As noted above, symbol addresses have not been |
| // assigned yet, so we can't generate the final reloc |
| // entry yet. We ultimately want: |
| // |
| // r_offset = s + r.Off |
| // r_info = R_390_RELATIVE |
| // r_addend = targ + r.Add |
| // |
| // The dynamic linker will set *offset = base address + |
| // addend. |
| // |
| // AddAddrPlus is used for r_offset and r_addend to |
| // generate new R_ADDR relocations that will update |
| // these fields in the 'reloc' phase. |
| rela := ldr.MakeSymbolUpdater(syms.Rela) |
| rela.AddAddrPlus(target.Arch, s, int64(r.Off())) |
| if r.Siz() == 8 { |
| rela.AddUint64(target.Arch, elf.R_INFO(0, uint32(elf.R_390_RELATIVE))) |
| } else { |
| ldr.Errorf(s, "unexpected relocation for dynamic symbol %s", ldr.SymName(targ)) |
| } |
| rela.AddAddrPlus(target.Arch, targ, r.Add()) |
| // Not mark r done here. So we still apply it statically, |
| // so in the file content we'll also have the right offset |
| // to the relocation target. So it can be examined statically |
| // (e.g. go version). |
| return true |
| } |
| } |
| |
| // Handle references to ELF symbols from our own object files. |
| return targType != sym.SDYNIMPORT |
| } |
| |
| func elfreloc1(ctxt *ld.Link, out *ld.OutBuf, ldr *loader.Loader, s loader.Sym, r loader.ExtReloc, ri int, sectoff int64) bool { |
| out.Write64(uint64(sectoff)) |
| |
| elfsym := ld.ElfSymForReloc(ctxt, r.Xsym) |
| siz := r.Size |
| switch r.Type { |
| default: |
| return false |
| case objabi.R_TLS_LE: |
| switch siz { |
| default: |
| return false |
| case 4: |
| // WARNING - silently ignored by linker in ELF64 |
| out.Write64(uint64(elf.R_390_TLS_LE32) | uint64(elfsym)<<32) |
| case 8: |
| // WARNING - silently ignored by linker in ELF32 |
| out.Write64(uint64(elf.R_390_TLS_LE64) | uint64(elfsym)<<32) |
| } |
| case objabi.R_TLS_IE: |
| switch siz { |
| default: |
| return false |
| case 4: |
| out.Write64(uint64(elf.R_390_TLS_IEENT) | uint64(elfsym)<<32) |
| } |
| case objabi.R_ADDR, objabi.R_DWARFSECREF: |
| switch siz { |
| default: |
| return false |
| case 4: |
| out.Write64(uint64(elf.R_390_32) | uint64(elfsym)<<32) |
| case 8: |
| out.Write64(uint64(elf.R_390_64) | uint64(elfsym)<<32) |
| } |
| case objabi.R_GOTPCREL: |
| if siz == 4 { |
| out.Write64(uint64(elf.R_390_GOTENT) | uint64(elfsym)<<32) |
| } else { |
| return false |
| } |
| case objabi.R_PCREL, objabi.R_PCRELDBL, objabi.R_CALL: |
| elfrel := elf.R_390_NONE |
| rVariant := ldr.RelocVariant(s, ri) |
| isdbl := rVariant&sym.RV_TYPE_MASK == sym.RV_390_DBL |
| // TODO(mundaym): all DBL style relocations should be |
| // signalled using the variant - see issue 14218. |
| switch r.Type { |
| case objabi.R_PCRELDBL, objabi.R_CALL: |
| isdbl = true |
| } |
| if ldr.SymType(r.Xsym) == sym.SDYNIMPORT && (ldr.SymElfType(r.Xsym) == elf.STT_FUNC || r.Type == objabi.R_CALL) { |
| if isdbl { |
| switch siz { |
| case 2: |
| elfrel = elf.R_390_PLT16DBL |
| case 4: |
| elfrel = elf.R_390_PLT32DBL |
| } |
| } else { |
| switch siz { |
| case 4: |
| elfrel = elf.R_390_PLT32 |
| case 8: |
| elfrel = elf.R_390_PLT64 |
| } |
| } |
| } else { |
| if isdbl { |
| switch siz { |
| case 2: |
| elfrel = elf.R_390_PC16DBL |
| case 4: |
| elfrel = elf.R_390_PC32DBL |
| } |
| } else { |
| switch siz { |
| case 2: |
| elfrel = elf.R_390_PC16 |
| case 4: |
| elfrel = elf.R_390_PC32 |
| case 8: |
| elfrel = elf.R_390_PC64 |
| } |
| } |
| } |
| if elfrel == elf.R_390_NONE { |
| return false // unsupported size/dbl combination |
| } |
| out.Write64(uint64(elfrel) | uint64(elfsym)<<32) |
| } |
| |
| out.Write64(uint64(r.Xadd)) |
| return true |
| } |
| |
| func elfsetupplt(ctxt *ld.Link, ldr *loader.Loader, plt, gotplt *loader.SymbolBuilder, dynamic loader.Sym) { |
| if plt.Size() == 0 { |
| // stg %r1,56(%r15) |
| plt.AddUint8(0xe3) |
| plt.AddUint8(0x10) |
| plt.AddUint8(0xf0) |
| plt.AddUint8(0x38) |
| plt.AddUint8(0x00) |
| plt.AddUint8(0x24) |
| // larl %r1,_GLOBAL_OFFSET_TABLE_ |
| plt.AddUint8(0xc0) |
| plt.AddUint8(0x10) |
| plt.AddSymRef(ctxt.Arch, gotplt.Sym(), 6, objabi.R_PCRELDBL, 4) |
| // mvc 48(8,%r15),8(%r1) |
| plt.AddUint8(0xd2) |
| plt.AddUint8(0x07) |
| plt.AddUint8(0xf0) |
| plt.AddUint8(0x30) |
| plt.AddUint8(0x10) |
| plt.AddUint8(0x08) |
| // lg %r1,16(%r1) |
| plt.AddUint8(0xe3) |
| plt.AddUint8(0x10) |
| plt.AddUint8(0x10) |
| plt.AddUint8(0x10) |
| plt.AddUint8(0x00) |
| plt.AddUint8(0x04) |
| // br %r1 |
| plt.AddUint8(0x07) |
| plt.AddUint8(0xf1) |
| // nopr %r0 |
| plt.AddUint8(0x07) |
| plt.AddUint8(0x00) |
| // nopr %r0 |
| plt.AddUint8(0x07) |
| plt.AddUint8(0x00) |
| // nopr %r0 |
| plt.AddUint8(0x07) |
| plt.AddUint8(0x00) |
| |
| // assume gotplt.size == 0 too |
| gotplt.AddAddrPlus(ctxt.Arch, dynamic, 0) |
| |
| gotplt.AddUint64(ctxt.Arch, 0) |
| gotplt.AddUint64(ctxt.Arch, 0) |
| } |
| } |
| |
| func machoreloc1(*sys.Arch, *ld.OutBuf, *loader.Loader, loader.Sym, loader.ExtReloc, int64) bool { |
| return false |
| } |
| |
| func archreloc(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, r loader.Reloc, s loader.Sym, val int64) (o int64, nExtReloc int, ok bool) { |
| return val, 0, false |
| } |
| |
| func archrelocvariant(target *ld.Target, ldr *loader.Loader, r loader.Reloc, rv sym.RelocVariant, s loader.Sym, t int64, p []byte) int64 { |
| switch rv & sym.RV_TYPE_MASK { |
| default: |
| ldr.Errorf(s, "unexpected relocation variant %d", rv) |
| return t |
| |
| case sym.RV_NONE: |
| return t |
| |
| case sym.RV_390_DBL: |
| if t&1 != 0 { |
| ldr.Errorf(s, "%s+%v is not 2-byte aligned", ldr.SymName(r.Sym()), ldr.SymValue(r.Sym())) |
| } |
| return t >> 1 |
| } |
| } |
| |
| func addpltsym(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s loader.Sym) { |
| if ldr.SymPlt(s) >= 0 { |
| return |
| } |
| |
| ld.Adddynsym(ldr, target, syms, s) |
| |
| if target.IsElf() { |
| plt := ldr.MakeSymbolUpdater(syms.PLT) |
| gotplt := ldr.MakeSymbolUpdater(syms.GOTPLT) |
| rela := ldr.MakeSymbolUpdater(syms.RelaPLT) |
| if plt.Size() == 0 { |
| panic("plt is not set up") |
| } |
| // larl %r1,_GLOBAL_OFFSET_TABLE_+index |
| |
| plt.AddUint8(0xc0) |
| plt.AddUint8(0x10) |
| plt.AddPCRelPlus(target.Arch, gotplt.Sym(), gotplt.Size()+6) |
| pltrelocs := plt.Relocs() |
| ldr.SetRelocVariant(plt.Sym(), pltrelocs.Count()-1, sym.RV_390_DBL) |
| |
| // add to gotplt: pointer to current pos in plt |
| gotplt.AddAddrPlus(target.Arch, plt.Sym(), plt.Size()+8) // weird but correct |
| // lg %r1,0(%r1) |
| plt.AddUint8(0xe3) |
| plt.AddUint8(0x10) |
| plt.AddUint8(0x10) |
| plt.AddUint8(0x00) |
| plt.AddUint8(0x00) |
| plt.AddUint8(0x04) |
| // br %r1 |
| plt.AddUint8(0x07) |
| plt.AddUint8(0xf1) |
| // basr %r1,%r0 |
| plt.AddUint8(0x0d) |
| plt.AddUint8(0x10) |
| // lgf %r1,12(%r1) |
| plt.AddUint8(0xe3) |
| plt.AddUint8(0x10) |
| plt.AddUint8(0x10) |
| plt.AddUint8(0x0c) |
| plt.AddUint8(0x00) |
| plt.AddUint8(0x14) |
| // jg .plt |
| plt.AddUint8(0xc0) |
| plt.AddUint8(0xf4) |
| |
| plt.AddUint32(target.Arch, uint32(-((plt.Size() - 2) >> 1))) // roll-your-own relocation |
| //.plt index |
| plt.AddUint32(target.Arch, uint32(rela.Size())) // rela size before current entry |
| |
| // rela |
| rela.AddAddrPlus(target.Arch, gotplt.Sym(), gotplt.Size()-8) |
| |
| sDynid := ldr.SymDynid(s) |
| rela.AddUint64(target.Arch, elf.R_INFO(uint32(sDynid), uint32(elf.R_390_JMP_SLOT))) |
| rela.AddUint64(target.Arch, 0) |
| |
| ldr.SetPlt(s, int32(plt.Size()-32)) |
| |
| } else { |
| ldr.Errorf(s, "addpltsym: unsupported binary format") |
| } |
| } |
| |
| // tlsIEtoLE converts TLS Initial Exec (IE) relocation to TLS Local Exec (LE). |
| // |
| // On s390x, the TLS IE sequence is: |
| // |
| // LARL %rN, <var>@INDNTPOFF ; 6 bytes - load address of GOT entry |
| // LG %rN, 0(%rN) ; 6 bytes - load offset from GOT |
| // |
| // We convert this to TLS LE by replacing it with: |
| // |
| // LGFI %rN, <offset> ; 6 bytes - load 32-bit sign-extended immediate |
| // BCR 0,0 ; 2 bytes - NOP |
| // BCR 0,0 ; 2 bytes - NOP |
| // BCR 0,0 ; 2 bytes - NOP |
| // |
| // The relocation offset points to byte 2 of the LARL instruction (the immediate field). |
| func tlsIEtoLE(P []byte, off, size int) { |
| // off is the offset of the relocation within the instruction sequence, |
| // which is at byte 2 of the LARL instruction (the 4-byte immediate). |
| // We need to work with the beginning of LARL (off-2) through LG (off+10). |
| |
| if off < 2 { |
| log.Fatalf("R_390_TLS_IEENT relocation at offset %d is too small", off) |
| } |
| |
| // Verify we have a LARL instruction (opcode 0xC0, second nibble 0x0) |
| // LARL format: C0 R0 I2 I2 I2 I2 (where R is register, I2 is 32-bit immediate) |
| if P[off-2] != 0xc0 || P[off-1]&0x0f != 0x00 { |
| log.Fatalf("R_390_TLS_IEENT relocation not preceded by LARL instruction: %02x %02x", P[off-2], P[off-1]) |
| } |
| |
| // Extract the register from LARL (upper nibble of second byte) |
| reg := P[off-1] >> 4 |
| |
| // Convert LARL to LGFI: change opcode from C0x0 to C0x1 |
| // LGFI format: C0 R1 I2 I2 I2 I2 |
| P[off-1] = (reg << 4) | 0x01 |
| |
| // The immediate field (bytes off to off+3) will be filled in by the linker |
| // with the TLS offset value. |
| |
| // Replace the LG instruction (6 bytes starting at off+4) with NOPs |
| // BCR 0,0 = 0x07 0x00 (2 bytes each, need 3 of them) |
| P[off+4] = 0x07 |
| P[off+5] = 0x00 |
| P[off+6] = 0x07 |
| P[off+7] = 0x00 |
| P[off+8] = 0x07 |
| P[off+9] = 0x00 |
| } |
