[llvm-branch-commits] [lld] 0a44c37 - [lld] Add target support for SystemZ (s390x) (#75643)

Tom Stellard via llvm-branch-commits llvm-branch-commits at lists.llvm.org
Fri Feb 16 05:18:11 PST 2024


Author: Ulrich Weigand
Date: 2024-02-16T05:17:32-08:00
New Revision: 0a44c3792a6ff799df5f100670d7e19d1bc49f03

URL: https://github.com/llvm/llvm-project/commit/0a44c3792a6ff799df5f100670d7e19d1bc49f03
DIFF: https://github.com/llvm/llvm-project/commit/0a44c3792a6ff799df5f100670d7e19d1bc49f03.diff

LOG: [lld] Add target support for SystemZ (s390x) (#75643)

This patch adds full support for linking SystemZ (ELF s390x) object
files. Support should be generally complete:
- All relocation types are supported.
- Full shared library support (DYNAMIC, GOT, PLT, ifunc).
- Relaxation of TLS and GOT relocations where appropriate.
- Platform-specific test cases.

In addition to new platform code and the obvious changes, there were a
few additional changes to common code:

- Add three new RelExpr members (R_GOTPLT_OFF, R_GOTPLT_PC, and
R_PLT_GOTREL) needed to support certain s390x relocations. I chose not
to use a platform-specific name since nothing in the definition of these
relocs is actually platform-specific; it is well possible that other
platforms will need the same.

- A couple of tweaks to TLS relocation handling, as the particular
semantics of the s390x versions differ slightly. See comments in the
code.

This was tested by building and testing >1500 Fedora packages, with only
a handful of failures; as these also have issues when building with LLD
on other architectures, they seem unrelated.

Co-authored-by: Tulio Magno Quites Machado Filho <tuliom at redhat.com>
(cherry picked from commit fe3406e349884e4ef61480dd0607f1e237102c74)

Added: 
    lld/ELF/Arch/SystemZ.cpp
    lld/test/ELF/Inputs/systemz-init.s
    lld/test/ELF/basic-systemz.s
    lld/test/ELF/emulation-systemz.s
    lld/test/ELF/lto/systemz.ll
    lld/test/ELF/systemz-got.s
    lld/test/ELF/systemz-gotent-relax-align.s
    lld/test/ELF/systemz-gotent-relax-und-dso.s
    lld/test/ELF/systemz-gotent-relax.s
    lld/test/ELF/systemz-ifunc-nonpreemptible.s
    lld/test/ELF/systemz-init-padding.s
    lld/test/ELF/systemz-pie.s
    lld/test/ELF/systemz-plt.s
    lld/test/ELF/systemz-reloc-abs.s
    lld/test/ELF/systemz-reloc-disp12.s
    lld/test/ELF/systemz-reloc-disp20.s
    lld/test/ELF/systemz-reloc-got.s
    lld/test/ELF/systemz-reloc-gotrel.s
    lld/test/ELF/systemz-reloc-pc16.s
    lld/test/ELF/systemz-reloc-pc32.s
    lld/test/ELF/systemz-reloc-pcdbl.s
    lld/test/ELF/systemz-tls-gd.s
    lld/test/ELF/systemz-tls-ie.s
    lld/test/ELF/systemz-tls-ld.s
    lld/test/ELF/systemz-tls-le.s

Modified: 
    lld/ELF/CMakeLists.txt
    lld/ELF/Driver.cpp
    lld/ELF/InputFiles.cpp
    lld/ELF/InputSection.cpp
    lld/ELF/Relocations.cpp
    lld/ELF/Relocations.h
    lld/ELF/ScriptParser.cpp
    lld/ELF/SyntheticSections.cpp
    lld/ELF/Target.cpp
    lld/ELF/Target.h
    lld/test/lit.cfg.py

Removed: 
    


################################################################################
diff  --git a/lld/ELF/Arch/SystemZ.cpp b/lld/ELF/Arch/SystemZ.cpp
new file mode 100644
index 00000000000000..d37db6877559dc
--- /dev/null
+++ b/lld/ELF/Arch/SystemZ.cpp
@@ -0,0 +1,607 @@
+//===- SystemZ.cpp --------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "OutputSections.h"
+#include "Symbols.h"
+#include "SyntheticSections.h"
+#include "Target.h"
+#include "lld/Common/ErrorHandler.h"
+#include "llvm/BinaryFormat/ELF.h"
+#include "llvm/Support/Endian.h"
+
+using namespace llvm;
+using namespace llvm::support::endian;
+using namespace llvm::ELF;
+using namespace lld;
+using namespace lld::elf;
+
+namespace {
+class SystemZ : public TargetInfo {
+public:
+  SystemZ();
+  int getTlsGdRelaxSkip(RelType type) const override;
+  RelExpr getRelExpr(RelType type, const Symbol &s,
+                     const uint8_t *loc) const override;
+  RelType getDynRel(RelType type) const override;
+  void writeGotHeader(uint8_t *buf) const override;
+  void writeGotPlt(uint8_t *buf, const Symbol &s) const override;
+  void writeIgotPlt(uint8_t *buf, const Symbol &s) const override;
+  void writePltHeader(uint8_t *buf) const override;
+  void addPltHeaderSymbols(InputSection &isd) const override;
+  void writePlt(uint8_t *buf, const Symbol &sym,
+                uint64_t pltEntryAddr) const override;
+  RelExpr adjustTlsExpr(RelType type, RelExpr expr) const override;
+  RelExpr adjustGotPcExpr(RelType type, int64_t addend,
+                          const uint8_t *loc) const override;
+  bool relaxOnce(int pass) const override;
+  void relocate(uint8_t *loc, const Relocation &rel,
+                uint64_t val) const override;
+  int64_t getImplicitAddend(const uint8_t *buf, RelType type) const override;
+
+private:
+  void relaxGot(uint8_t *loc, const Relocation &rel, uint64_t val) const;
+  void relaxTlsGdToIe(uint8_t *loc, const Relocation &rel, uint64_t val) const;
+  void relaxTlsGdToLe(uint8_t *loc, const Relocation &rel, uint64_t val) const;
+  void relaxTlsLdToLe(uint8_t *loc, const Relocation &rel, uint64_t val) const;
+};
+} // namespace
+
+SystemZ::SystemZ() {
+  copyRel = R_390_COPY;
+  gotRel = R_390_GLOB_DAT;
+  pltRel = R_390_JMP_SLOT;
+  relativeRel = R_390_RELATIVE;
+  iRelativeRel = R_390_IRELATIVE;
+  symbolicRel = R_390_64;
+  tlsGotRel = R_390_TLS_TPOFF;
+  tlsModuleIndexRel = R_390_TLS_DTPMOD;
+  tlsOffsetRel = R_390_TLS_DTPOFF;
+  gotHeaderEntriesNum = 3;
+  gotPltHeaderEntriesNum = 0;
+  gotEntrySize = 8;
+  pltHeaderSize = 32;
+  pltEntrySize = 32;
+  ipltEntrySize = 32;
+
+  // This "trap instruction" is used to fill gaps between sections.
+  // On SystemZ, the behavior of the GNU ld is to fill those gaps
+  // with nop instructions instead - and unfortunately the default
+  // glibc crt object files (used to) rely on that behavior since
+  // they use an alignment on the .init section fragments that causes
+  // gaps which must be filled with nops as they are being executed.
+  // Therefore, we provide a nop instruction as "trapInstr" here.
+  trapInstr = {0x07, 0x07, 0x07, 0x07};
+
+  defaultImageBase = 0x1000000;
+}
+
+RelExpr SystemZ::getRelExpr(RelType type, const Symbol &s,
+                            const uint8_t *loc) const {
+  switch (type) {
+  case R_390_NONE:
+    return R_NONE;
+  // Relocations targeting the symbol value.
+  case R_390_8:
+  case R_390_12:
+  case R_390_16:
+  case R_390_20:
+  case R_390_32:
+  case R_390_64:
+    return R_ABS;
+  case R_390_PC16:
+  case R_390_PC32:
+  case R_390_PC64:
+  case R_390_PC12DBL:
+  case R_390_PC16DBL:
+  case R_390_PC24DBL:
+  case R_390_PC32DBL:
+    return R_PC;
+  case R_390_GOTOFF16:
+  case R_390_GOTOFF: // a.k.a. R_390_GOTOFF32
+  case R_390_GOTOFF64:
+    return R_GOTREL;
+  // Relocations targeting the PLT associated with the symbol.
+  case R_390_PLT32:
+  case R_390_PLT64:
+  case R_390_PLT12DBL:
+  case R_390_PLT16DBL:
+  case R_390_PLT24DBL:
+  case R_390_PLT32DBL:
+    return R_PLT_PC;
+  case R_390_PLTOFF16:
+  case R_390_PLTOFF32:
+  case R_390_PLTOFF64:
+    return R_PLT_GOTREL;
+  // Relocations targeting the GOT entry associated with the symbol.
+  case R_390_GOTENT:
+    return R_GOT_PC;
+  case R_390_GOT12:
+  case R_390_GOT16:
+  case R_390_GOT20:
+  case R_390_GOT32:
+  case R_390_GOT64:
+    return R_GOT_OFF;
+  // Relocations targeting the GOTPLT entry associated with the symbol.
+  case R_390_GOTPLTENT:
+    return R_GOTPLT_PC;
+  case R_390_GOTPLT12:
+  case R_390_GOTPLT16:
+  case R_390_GOTPLT20:
+  case R_390_GOTPLT32:
+  case R_390_GOTPLT64:
+    return R_GOTPLT_GOTREL;
+  // Relocations targeting _GLOBAL_OFFSET_TABLE_.
+  case R_390_GOTPC:
+  case R_390_GOTPCDBL:
+    return R_GOTONLY_PC;
+  // TLS-related relocations.
+  case R_390_TLS_LOAD:
+    return R_NONE;
+  case R_390_TLS_GDCALL:
+    return R_TLSGD_PC;
+  case R_390_TLS_LDCALL:
+    return R_TLSLD_PC;
+  case R_390_TLS_GD32:
+  case R_390_TLS_GD64:
+    return R_TLSGD_GOT;
+  case R_390_TLS_LDM32:
+  case R_390_TLS_LDM64:
+    return R_TLSLD_GOT;
+  case R_390_TLS_LDO32:
+  case R_390_TLS_LDO64:
+    return R_DTPREL;
+  case R_390_TLS_LE32:
+  case R_390_TLS_LE64:
+    return R_TPREL;
+  case R_390_TLS_IE32:
+  case R_390_TLS_IE64:
+    return R_GOT;
+  case R_390_TLS_GOTIE12:
+  case R_390_TLS_GOTIE20:
+  case R_390_TLS_GOTIE32:
+  case R_390_TLS_GOTIE64:
+    return R_GOT_OFF;
+  case R_390_TLS_IEENT:
+    return R_GOT_PC;
+
+  default:
+    error(getErrorLocation(loc) + "unknown relocation (" + Twine(type) +
+          ") against symbol " + toString(s));
+    return R_NONE;
+  }
+}
+
+void SystemZ::writeGotHeader(uint8_t *buf) const {
+  // _GLOBAL_OFFSET_TABLE_[0] holds the value of _DYNAMIC.
+  // _GLOBAL_OFFSET_TABLE_[1] and [2] are reserved.
+  write64be(buf, mainPart->dynamic->getVA());
+}
+
+void SystemZ::writeGotPlt(uint8_t *buf, const Symbol &s) const {
+  write64be(buf, s.getPltVA() + 14);
+}
+
+void SystemZ::writeIgotPlt(uint8_t *buf, const Symbol &s) const {
+  if (config->writeAddends)
+    write64be(buf, s.getVA());
+}
+
+void SystemZ::writePltHeader(uint8_t *buf) const {
+  const uint8_t pltData[] = {
+      0xe3, 0x10, 0xf0, 0x38, 0x00, 0x24, // stg     %r1,56(%r15)
+      0xc0, 0x10, 0x00, 0x00, 0x00, 0x00, // larl    %r1,_GLOBAL_OFFSET_TABLE_
+      0xd2, 0x07, 0xf0, 0x30, 0x10, 0x08, // mvc     48(8,%r15),8(%r1)
+      0xe3, 0x10, 0x10, 0x10, 0x00, 0x04, // lg      %r1,16(%r1)
+      0x07, 0xf1,                         // br      %r1
+      0x07, 0x00,                         // nopr
+      0x07, 0x00,                         // nopr
+      0x07, 0x00,                         // nopr
+  };
+  memcpy(buf, pltData, sizeof(pltData));
+  uint64_t got = in.got->getVA();
+  uint64_t plt = in.plt->getVA();
+  write32be(buf + 8, (got - plt - 6) >> 1);
+}
+
+void SystemZ::addPltHeaderSymbols(InputSection &isec) const {
+  // The PLT header needs a reference to _GLOBAL_OFFSET_TABLE_, so we
+  // must ensure the .got section is created even if otherwise unused.
+  in.got->hasGotOffRel.store(true, std::memory_order_relaxed);
+}
+
+void SystemZ::writePlt(uint8_t *buf, const Symbol &sym,
+                       uint64_t pltEntryAddr) const {
+  const uint8_t inst[] = {
+      0xc0, 0x10, 0x00, 0x00, 0x00, 0x00, // larl    %r1,<.got.plt slot>
+      0xe3, 0x10, 0x10, 0x00, 0x00, 0x04, // lg      %r1,0(%r1)
+      0x07, 0xf1,                         // br      %r1
+      0x0d, 0x10,                         // basr    %r1,%r0
+      0xe3, 0x10, 0x10, 0x0c, 0x00, 0x14, // lgf     %r1,12(%r1)
+      0xc0, 0xf4, 0x00, 0x00, 0x00, 0x00, // jg      <plt header>
+      0x00, 0x00, 0x00, 0x00,             // <relocation offset>
+  };
+  memcpy(buf, inst, sizeof(inst));
+
+  write32be(buf + 2, (sym.getGotPltVA() - pltEntryAddr) >> 1);
+  write32be(buf + 24, (in.plt->getVA() - pltEntryAddr - 22) >> 1);
+  write32be(buf + 28, in.relaPlt->entsize * sym.getPltIdx());
+}
+
+int64_t SystemZ::getImplicitAddend(const uint8_t *buf, RelType type) const {
+  switch (type) {
+  case R_390_8:
+    return SignExtend64<8>(*buf);
+  case R_390_16:
+  case R_390_PC16:
+    return SignExtend64<16>(read16be(buf));
+  case R_390_PC16DBL:
+    return SignExtend64<16>(read16be(buf)) << 1;
+  case R_390_32:
+  case R_390_PC32:
+    return SignExtend64<32>(read32be(buf));
+  case R_390_PC32DBL:
+    return SignExtend64<32>(read32be(buf)) << 1;
+  case R_390_64:
+  case R_390_PC64:
+  case R_390_TLS_DTPMOD:
+  case R_390_TLS_DTPOFF:
+  case R_390_TLS_TPOFF:
+  case R_390_GLOB_DAT:
+  case R_390_RELATIVE:
+  case R_390_IRELATIVE:
+    return read64be(buf);
+  case R_390_COPY:
+  case R_390_JMP_SLOT:
+  case R_390_NONE:
+    // These relocations are defined as not having an implicit addend.
+    return 0;
+  default:
+    internalLinkerError(getErrorLocation(buf),
+                        "cannot read addend for relocation " + toString(type));
+    return 0;
+  }
+}
+
+RelType SystemZ::getDynRel(RelType type) const {
+  if (type == R_390_64 || type == R_390_PC64)
+    return type;
+  return R_390_NONE;
+}
+
+RelExpr SystemZ::adjustTlsExpr(RelType type, RelExpr expr) const {
+  if (expr == R_RELAX_TLS_GD_TO_IE)
+    return R_RELAX_TLS_GD_TO_IE_GOT_OFF;
+  return expr;
+}
+
+int SystemZ::getTlsGdRelaxSkip(RelType type) const {
+  // A __tls_get_offset call instruction is marked with 2 relocations:
+  //
+  //   R_390_TLS_GDCALL / R_390_TLS_LDCALL: marker relocation
+  //   R_390_PLT32DBL: __tls_get_offset
+  //
+  // After the relaxation we no longer call __tls_get_offset and should skip
+  // both relocations to not create a false dependence on __tls_get_offset
+  // being defined.
+  //
+  // Note that this mechanism only works correctly if the R_390_TLS_[GL]DCALL
+  // is seen immediately *before* the R_390_PLT32DBL.  Unfortunately, current
+  // compilers on the platform will typically generate the inverse sequence.
+  // To fix this, we sort relocations by offset in RelocationScanner::scan;
+  // this ensures the correct sequence as the R_390_TLS_[GL]DCALL applies to
+  // the first byte of the brasl instruction, while the R_390_PLT32DBL applies
+  // to its third byte (the relative displacement).
+
+  if (type == R_390_TLS_GDCALL || type == R_390_TLS_LDCALL)
+    return 2;
+  return 1;
+}
+
+void SystemZ::relaxTlsGdToIe(uint8_t *loc, const Relocation &rel,
+                             uint64_t val) const {
+  // The general-dynamic code sequence for a global `x`:
+  //
+  // Instruction                      Relocation       Symbol
+  // ear %rX,%a0
+  // sllg %rX,%rX,32
+  // ear %rX,%a1
+  // larl %r12,_GLOBAL_OFFSET_TABLE_  R_390_GOTPCDBL   _GLOBAL_OFFSET_TABLE_
+  // lgrl %r2,.LC0                    R_390_PC32DBL    .LC0
+  // brasl %r14,__tls_get_offset at plt  R_390_TLS_GDCALL x
+  //            :tls_gdcall:x         R_390_PLT32DBL   __tls_get_offset
+  // la %r2,0(%r2,%rX)
+  //
+  // .LC0:
+  // .quad   x at TLSGD                  R_390_TLS_GD64   x
+  //
+  // Relaxing to initial-exec entails:
+  // 1) Replacing the call by a load from the GOT.
+  // 2) Replacing the relocation on the constant LC0 by R_390_TLS_GOTIE64.
+
+  switch (rel.type) {
+  case R_390_TLS_GDCALL:
+    // brasl %r14,__tls_get_offset at plt -> lg %r2,0(%r2,%r12)
+    write16be(loc, 0xe322);
+    write32be(loc + 2, 0xc0000004);
+    break;
+  case R_390_TLS_GD64:
+    relocateNoSym(loc, R_390_TLS_GOTIE64, val);
+    break;
+  default:
+    llvm_unreachable("unsupported relocation for TLS GD to IE relaxation");
+  }
+}
+
+void SystemZ::relaxTlsGdToLe(uint8_t *loc, const Relocation &rel,
+                             uint64_t val) const {
+  // The general-dynamic code sequence for a global `x`:
+  //
+  // Instruction                      Relocation       Symbol
+  // ear %rX,%a0
+  // sllg %rX,%rX,32
+  // ear %rX,%a1
+  // larl %r12,_GLOBAL_OFFSET_TABLE_  R_390_GOTPCDBL   _GLOBAL_OFFSET_TABLE_
+  // lgrl %r2,.LC0                    R_390_PC32DBL    .LC0
+  // brasl %r14,__tls_get_offset at plt  R_390_TLS_GDCALL x
+  //            :tls_gdcall:x         R_390_PLT32DBL   __tls_get_offset
+  // la %r2,0(%r2,%rX)
+  //
+  // .LC0:
+  // .quad   x at tlsgd                  R_390_TLS_GD64   x
+  //
+  // Relaxing to local-exec entails:
+  // 1) Replacing the call by a nop.
+  // 2) Replacing the relocation on the constant LC0 by R_390_TLS_LE64.
+
+  switch (rel.type) {
+  case R_390_TLS_GDCALL:
+    // brasl %r14,__tls_get_offset at plt -> brcl 0,.
+    write16be(loc, 0xc004);
+    write32be(loc + 2, 0x00000000);
+    break;
+  case R_390_TLS_GD64:
+    relocateNoSym(loc, R_390_TLS_LE64, val);
+    break;
+  default:
+    llvm_unreachable("unsupported relocation for TLS GD to LE relaxation");
+  }
+}
+
+void SystemZ::relaxTlsLdToLe(uint8_t *loc, const Relocation &rel,
+                             uint64_t val) const {
+  // The local-dynamic code sequence for a global `x`:
+  //
+  // Instruction                      Relocation       Symbol
+  // ear %rX,%a0
+  // sllg %rX,%rX,32
+  // ear %rX,%a1
+  // larl %r12,_GLOBAL_OFFSET_TABLE_  R_390_GOTPCDBL   _GLOBAL_OFFSET_TABLE_
+  // lgrl %r2,.LC0                    R_390_PC32DBL    .LC0
+  // brasl %r14,__tls_get_offset at plt  R_390_TLS_LDCALL <sym>
+  //            :tls_ldcall:<sym>     R_390_PLT32DBL   __tls_get_offset
+  // la %r2,0(%r2,%rX)
+  // lgrl %rY,.LC1                    R_390_PC32DBL    .LC1
+  // la %r2,0(%r2,%rY)
+  //
+  // .LC0:
+  // .quad   <sym>@tlsldm             R_390_TLS_LDM64  <sym>
+  // .LC1:
+  // .quad   x at dtpoff                 R_390_TLS_LDO64  x
+  //
+  // Relaxing to local-exec entails:
+  // 1) Replacing the call by a nop.
+  // 2) Replacing the constant LC0 by 0 (i.e. ignoring the relocation).
+  // 3) Replacing the relocation on the constant LC1 by R_390_TLS_LE64.
+
+  switch (rel.type) {
+  case R_390_TLS_LDCALL:
+    // brasl %r14,__tls_get_offset at plt -> brcl 0,.
+    write16be(loc, 0xc004);
+    write32be(loc + 2, 0x00000000);
+    break;
+  case R_390_TLS_LDM64:
+    break;
+  case R_390_TLS_LDO64:
+    relocateNoSym(loc, R_390_TLS_LE64, val);
+    break;
+  default:
+    llvm_unreachable("unsupported relocation for TLS LD to LE relaxation");
+  }
+}
+
+RelExpr SystemZ::adjustGotPcExpr(RelType type, int64_t addend,
+                                 const uint8_t *loc) const {
+  // Only R_390_GOTENT with addend 2 can be relaxed.
+  if (!config->relax || addend != 2 || type != R_390_GOTENT)
+    return R_GOT_PC;
+  const uint16_t op = read16be(loc - 2);
+
+  // lgrl rx,sym at GOTENT -> larl rx, sym
+  // This relaxation is legal if "sym" binds locally (which was already
+  // verified by our caller) and is in-range and properly aligned for a
+  // LARL instruction.  We cannot verify the latter constraint here, so
+  // we assume it is true and revert the decision later on in relaxOnce
+  // if necessary.
+  if ((op & 0xff0f) == 0xc408)
+    return R_RELAX_GOT_PC;
+
+  return R_GOT_PC;
+}
+
+bool SystemZ::relaxOnce(int pass) const {
+  // If we decided in adjustGotPcExpr to relax a R_390_GOTENT,
+  // we need to validate the target symbol is in-range and aligned.
+  SmallVector<InputSection *, 0> storage;
+  bool changed = false;
+  for (OutputSection *osec : outputSections) {
+    if (!(osec->flags & SHF_EXECINSTR))
+      continue;
+    for (InputSection *sec : getInputSections(*osec, storage)) {
+      for (Relocation &rel : sec->relocs()) {
+        if (rel.expr != R_RELAX_GOT_PC)
+          continue;
+
+        uint64_t v = sec->getRelocTargetVA(
+            sec->file, rel.type, rel.addend,
+            sec->getOutputSection()->addr + rel.offset, *rel.sym, rel.expr);
+        if (isInt<33>(v) && !(v & 1))
+          continue;
+        if (rel.sym->auxIdx == 0) {
+          rel.sym->allocateAux();
+          addGotEntry(*rel.sym);
+          changed = true;
+        }
+        rel.expr = R_GOT_PC;
+      }
+    }
+  }
+  return changed;
+}
+
+void SystemZ::relaxGot(uint8_t *loc, const Relocation &rel,
+                       uint64_t val) const {
+  assert(isInt<33>(val) &&
+         "R_390_GOTENT should not have been relaxed if it overflows");
+  assert(!(val & 1) &&
+         "R_390_GOTENT should not have been relaxed if it is misaligned");
+  const uint16_t op = read16be(loc - 2);
+
+  // lgrl rx,sym at GOTENT -> larl rx, sym
+  if ((op & 0xff0f) == 0xc408) {
+    write16be(loc - 2, 0xc000 | (op & 0x00f0));
+    write32be(loc, val >> 1);
+  }
+}
+
+void SystemZ::relocate(uint8_t *loc, const Relocation &rel,
+                       uint64_t val) const {
+  switch (rel.expr) {
+  case R_RELAX_GOT_PC:
+    return relaxGot(loc, rel, val);
+  case R_RELAX_TLS_GD_TO_IE_GOT_OFF:
+    return relaxTlsGdToIe(loc, rel, val);
+  case R_RELAX_TLS_GD_TO_LE:
+    return relaxTlsGdToLe(loc, rel, val);
+  case R_RELAX_TLS_LD_TO_LE:
+    return relaxTlsLdToLe(loc, rel, val);
+  default:
+    break;
+  }
+  switch (rel.type) {
+  case R_390_8:
+    checkIntUInt(loc, val, 8, rel);
+    *loc = val;
+    break;
+  case R_390_12:
+  case R_390_GOT12:
+  case R_390_GOTPLT12:
+  case R_390_TLS_GOTIE12:
+    checkUInt(loc, val, 12, rel);
+    write16be(loc, (read16be(loc) & 0xF000) | val);
+    break;
+  case R_390_PC12DBL:
+  case R_390_PLT12DBL:
+    checkInt(loc, val, 13, rel);
+    checkAlignment(loc, val, 2, rel);
+    write16be(loc, (read16be(loc) & 0xF000) | ((val >> 1) & 0x0FFF));
+    break;
+  case R_390_16:
+  case R_390_GOT16:
+  case R_390_GOTPLT16:
+  case R_390_GOTOFF16:
+  case R_390_PLTOFF16:
+    checkIntUInt(loc, val, 16, rel);
+    write16be(loc, val);
+    break;
+  case R_390_PC16:
+    checkInt(loc, val, 16, rel);
+    write16be(loc, val);
+    break;
+  case R_390_PC16DBL:
+  case R_390_PLT16DBL:
+    checkInt(loc, val, 17, rel);
+    checkAlignment(loc, val, 2, rel);
+    write16be(loc, val >> 1);
+    break;
+  case R_390_20:
+  case R_390_GOT20:
+  case R_390_GOTPLT20:
+  case R_390_TLS_GOTIE20:
+    checkInt(loc, val, 20, rel);
+    write32be(loc, (read32be(loc) & 0xF00000FF) | ((val & 0xFFF) << 16) |
+                       ((val & 0xFF000) >> 4));
+    break;
+  case R_390_PC24DBL:
+  case R_390_PLT24DBL:
+    checkInt(loc, val, 25, rel);
+    checkAlignment(loc, val, 2, rel);
+    loc[0] = val >> 17;
+    loc[1] = val >> 9;
+    loc[2] = val >> 1;
+    break;
+  case R_390_32:
+  case R_390_GOT32:
+  case R_390_GOTPLT32:
+  case R_390_GOTOFF:
+  case R_390_PLTOFF32:
+  case R_390_TLS_IE32:
+  case R_390_TLS_GOTIE32:
+  case R_390_TLS_GD32:
+  case R_390_TLS_LDM32:
+  case R_390_TLS_LDO32:
+  case R_390_TLS_LE32:
+    checkIntUInt(loc, val, 32, rel);
+    write32be(loc, val);
+    break;
+  case R_390_PC32:
+  case R_390_PLT32:
+    checkInt(loc, val, 32, rel);
+    write32be(loc, val);
+    break;
+  case R_390_PC32DBL:
+  case R_390_PLT32DBL:
+  case R_390_GOTPCDBL:
+  case R_390_GOTENT:
+  case R_390_GOTPLTENT:
+  case R_390_TLS_IEENT:
+    checkInt(loc, val, 33, rel);
+    checkAlignment(loc, val, 2, rel);
+    write32be(loc, val >> 1);
+    break;
+  case R_390_64:
+  case R_390_PC64:
+  case R_390_PLT64:
+  case R_390_GOT64:
+  case R_390_GOTPLT64:
+  case R_390_GOTOFF64:
+  case R_390_PLTOFF64:
+  case R_390_GOTPC:
+  case R_390_TLS_IE64:
+  case R_390_TLS_GOTIE64:
+  case R_390_TLS_GD64:
+  case R_390_TLS_LDM64:
+  case R_390_TLS_LDO64:
+  case R_390_TLS_LE64:
+  case R_390_TLS_DTPMOD:
+  case R_390_TLS_DTPOFF:
+  case R_390_TLS_TPOFF:
+    write64be(loc, val);
+    break;
+  case R_390_TLS_LOAD:
+  case R_390_TLS_GDCALL:
+  case R_390_TLS_LDCALL:
+    break;
+  default:
+    llvm_unreachable("unknown relocation");
+  }
+}
+
+TargetInfo *elf::getSystemZTargetInfo() {
+  static SystemZ t;
+  return &t;
+}

diff  --git a/lld/ELF/CMakeLists.txt b/lld/ELF/CMakeLists.txt
index 475f7dea1dd7e9..83d816ddb0601e 100644
--- a/lld/ELF/CMakeLists.txt
+++ b/lld/ELF/CMakeLists.txt
@@ -33,6 +33,7 @@ add_lld_library(lldELF
   Arch/PPC64.cpp
   Arch/RISCV.cpp
   Arch/SPARCV9.cpp
+  Arch/SystemZ.cpp
   Arch/X86.cpp
   Arch/X86_64.cpp
   ARMErrataFix.cpp

diff  --git a/lld/ELF/Driver.cpp b/lld/ELF/Driver.cpp
index f4b7d1c9d5b973..8b2c32b1534821 100644
--- a/lld/ELF/Driver.cpp
+++ b/lld/ELF/Driver.cpp
@@ -200,6 +200,7 @@ static std::tuple<ELFKind, uint16_t, uint8_t> parseEmulation(StringRef emul) {
           .Case("msp430elf", {ELF32LEKind, EM_MSP430})
           .Case("elf64_amdgpu", {ELF64LEKind, EM_AMDGPU})
           .Case("elf64loongarch", {ELF64LEKind, EM_LOONGARCH})
+          .Case("elf64_s390", {ELF64BEKind, EM_S390})
           .Default({ELFNoneKind, EM_NONE});
 
   if (ret.first == ELFNoneKind)
@@ -1137,7 +1138,7 @@ static SmallVector<StringRef, 0> getSymbolOrderingFile(MemoryBufferRef mb) {
 static bool getIsRela(opt::InputArgList &args) {
   // The psABI specifies the default relocation entry format.
   bool rela = is_contained({EM_AARCH64, EM_AMDGPU, EM_HEXAGON, EM_LOONGARCH,
-                            EM_PPC, EM_PPC64, EM_RISCV, EM_X86_64},
+                            EM_PPC, EM_PPC64, EM_RISCV, EM_S390, EM_X86_64},
                            config->emachine);
   // If -z rel or -z rela is specified, use the last option.
   for (auto *arg : args.filtered(OPT_z)) {

diff  --git a/lld/ELF/InputFiles.cpp b/lld/ELF/InputFiles.cpp
index a292e873e72f71..6c7ef27cbd4942 100644
--- a/lld/ELF/InputFiles.cpp
+++ b/lld/ELF/InputFiles.cpp
@@ -1614,6 +1614,8 @@ static uint16_t getBitcodeMachineKind(StringRef path, const Triple &t) {
     return EM_RISCV;
   case Triple::sparcv9:
     return EM_SPARCV9;
+  case Triple::systemz:
+    return EM_S390;
   case Triple::x86:
     return t.isOSIAMCU() ? EM_IAMCU : EM_386;
   case Triple::x86_64:

diff  --git a/lld/ELF/InputSection.cpp b/lld/ELF/InputSection.cpp
index 0e0b9783bd88a0..71870539d531c1 100644
--- a/lld/ELF/InputSection.cpp
+++ b/lld/ELF/InputSection.cpp
@@ -654,6 +654,7 @@ static int64_t getTlsTpOffset(const Symbol &s) {
 
     // Variant 2.
   case EM_HEXAGON:
+  case EM_S390:
   case EM_SPARCV9:
   case EM_386:
   case EM_X86_64:
@@ -716,6 +717,10 @@ uint64_t InputSectionBase::getRelocTargetVA(const InputFile *file, RelType type,
   case R_GOT_PC:
   case R_RELAX_TLS_GD_TO_IE:
     return sym.getGotVA() + a - p;
+  case R_GOTPLT_GOTREL:
+    return sym.getGotPltVA() + a - in.got->getVA();
+  case R_GOTPLT_PC:
+    return sym.getGotPltVA() + a - p;
   case R_LOONGARCH_GOT_PAGE_PC:
     if (sym.hasFlag(NEEDS_TLSGD))
       return getLoongArchPageDelta(in.got->getGlobalDynAddr(sym) + a, p, type);
@@ -807,6 +812,8 @@ uint64_t InputSectionBase::getRelocTargetVA(const InputFile *file, RelType type,
     return getLoongArchPageDelta(sym.getPltVA() + a, p, type);
   case R_PLT_GOTPLT:
     return sym.getPltVA() + a - in.gotPlt->getVA();
+  case R_PLT_GOTREL:
+    return sym.getPltVA() + a - in.got->getVA();
   case R_PPC32_PLTREL:
     // R_PPC_PLTREL24 uses the addend (usually 0 or 0x8000) to indicate r30
     // stores _GLOBAL_OFFSET_TABLE_ or .got2+0x8000. The addend is ignored for

diff  --git a/lld/ELF/Relocations.cpp b/lld/ELF/Relocations.cpp
index 79c8230724ade7..f64b4219e0acc1 100644
--- a/lld/ELF/Relocations.cpp
+++ b/lld/ELF/Relocations.cpp
@@ -203,8 +203,9 @@ static bool isAbsoluteValue(const Symbol &sym) {
 
 // Returns true if Expr refers a PLT entry.
 static bool needsPlt(RelExpr expr) {
-  return oneof<R_PLT, R_PLT_PC, R_PLT_GOTPLT, R_LOONGARCH_PLT_PAGE_PC,
-               R_PPC32_PLTREL, R_PPC64_CALL_PLT>(expr);
+  return oneof<R_PLT, R_PLT_PC, R_PLT_GOTREL, R_PLT_GOTPLT, R_GOTPLT_GOTREL,
+               R_GOTPLT_PC, R_LOONGARCH_PLT_PAGE_PC, R_PPC32_PLTREL,
+               R_PPC64_CALL_PLT>(expr);
 }
 
 bool lld::elf::needsGot(RelExpr expr) {
@@ -233,6 +234,8 @@ static RelExpr toPlt(RelExpr expr) {
     return R_PLT_PC;
   case R_ABS:
     return R_PLT;
+  case R_GOTREL:
+    return R_PLT_GOTREL;
   default:
     return expr;
   }
@@ -253,6 +256,8 @@ static RelExpr fromPlt(RelExpr expr) {
     return R_ABS;
   case R_PLT_GOTPLT:
     return R_GOTPLTREL;
+  case R_PLT_GOTREL:
+    return R_GOTREL;
   default:
     return expr;
   }
@@ -979,10 +984,10 @@ bool RelocationScanner::isStaticLinkTimeConstant(RelExpr e, RelType type,
   if (oneof<R_GOTPLT, R_GOT_OFF, R_RELAX_HINT, R_MIPS_GOT_LOCAL_PAGE,
             R_MIPS_GOTREL, R_MIPS_GOT_OFF, R_MIPS_GOT_OFF32, R_MIPS_GOT_GP_PC,
             R_AARCH64_GOT_PAGE_PC, R_GOT_PC, R_GOTONLY_PC, R_GOTPLTONLY_PC,
-            R_PLT_PC, R_PLT_GOTPLT, R_PPC32_PLTREL, R_PPC64_CALL_PLT,
-            R_PPC64_RELAX_TOC, R_RISCV_ADD, R_AARCH64_GOT_PAGE,
-            R_LOONGARCH_PLT_PAGE_PC, R_LOONGARCH_GOT, R_LOONGARCH_GOT_PAGE_PC>(
-          e))
+            R_PLT_PC, R_PLT_GOTREL, R_PLT_GOTPLT, R_GOTPLT_GOTREL, R_GOTPLT_PC,
+            R_PPC32_PLTREL, R_PPC64_CALL_PLT, R_PPC64_RELAX_TOC, R_RISCV_ADD,
+            R_AARCH64_GOT_PAGE, R_LOONGARCH_PLT_PAGE_PC, R_LOONGARCH_GOT,
+            R_LOONGARCH_GOT_PAGE_PC>(e))
     return true;
 
   // These never do, except if the entire file is position dependent or if
@@ -1374,8 +1379,8 @@ static unsigned handleTlsRelocation(RelType type, Symbol &sym,
             R_LOONGARCH_GOT_PAGE_PC, R_GOT_OFF, R_TLSIE_HINT>(expr)) {
     ctx.hasTlsIe.store(true, std::memory_order_relaxed);
     // Initial-Exec relocs can be optimized to Local-Exec if the symbol is
-    // locally defined.
-    if (execOptimize && isLocalInExecutable) {
+    // locally defined.  This is not supported on SystemZ.
+    if (execOptimize && isLocalInExecutable && config->emachine != EM_S390) {
       c.addReloc({R_RELAX_TLS_IE_TO_LE, type, offset, addend, &sym});
     } else if (expr != R_TLSIE_HINT) {
       sym.setFlags(NEEDS_TLSIE);
@@ -1534,8 +1539,10 @@ void RelocationScanner::scan(ArrayRef<RelTy> rels) {
   // For EhInputSection, OffsetGetter expects the relocations to be sorted by
   // r_offset. In rare cases (.eh_frame pieces are reordered by a linker
   // script), the relocations may be unordered.
+  // On SystemZ, all sections need to be sorted by r_offset, to allow TLS
+  // relaxation to be handled correctly - see SystemZ::getTlsGdRelaxSkip.
   SmallVector<RelTy, 0> storage;
-  if (isa<EhInputSection>(sec))
+  if (isa<EhInputSection>(sec) || config->emachine == EM_S390)
     rels = sortRels(rels, storage);
 
   end = static_cast<const void *>(rels.end());

diff  --git a/lld/ELF/Relocations.h b/lld/ELF/Relocations.h
index cfb9092149f3e0..7eb8a811e6934f 100644
--- a/lld/ELF/Relocations.h
+++ b/lld/ELF/Relocations.h
@@ -40,11 +40,14 @@ enum RelExpr {
   R_GOTPLT,
   R_GOTPLTREL,
   R_GOTREL,
+  R_GOTPLT_GOTREL,
+  R_GOTPLT_PC,
   R_NONE,
   R_PC,
   R_PLT,
   R_PLT_PC,
   R_PLT_GOTPLT,
+  R_PLT_GOTREL,
   R_RELAX_HINT,
   R_RELAX_GOT_PC,
   R_RELAX_GOT_PC_NOPIC,

diff  --git a/lld/ELF/ScriptParser.cpp b/lld/ELF/ScriptParser.cpp
index dd69916d6b05e8..f0ede1f43bbdb3 100644
--- a/lld/ELF/ScriptParser.cpp
+++ b/lld/ELF/ScriptParser.cpp
@@ -445,6 +445,7 @@ static std::pair<ELFKind, uint16_t> parseBfdName(StringRef s) {
       .Case("elf32-msp430", {ELF32LEKind, EM_MSP430})
       .Case("elf32-loongarch", {ELF32LEKind, EM_LOONGARCH})
       .Case("elf64-loongarch", {ELF64LEKind, EM_LOONGARCH})
+      .Case("elf64-s390", {ELF64BEKind, EM_S390})
       .Default({ELFNoneKind, EM_NONE});
 }
 

diff  --git a/lld/ELF/SyntheticSections.cpp b/lld/ELF/SyntheticSections.cpp
index 4b413163314b2e..bada394aa30d7d 100644
--- a/lld/ELF/SyntheticSections.cpp
+++ b/lld/ELF/SyntheticSections.cpp
@@ -1419,6 +1419,9 @@ DynamicSection<ELFT>::computeContents() {
     case EM_MIPS:
       addInSec(DT_MIPS_PLTGOT, *in.gotPlt);
       break;
+    case EM_S390:
+      addInSec(DT_PLTGOT, *in.got);
+      break;
     case EM_SPARCV9:
       addInSec(DT_PLTGOT, *in.plt);
       break;

diff  --git a/lld/ELF/Target.cpp b/lld/ELF/Target.cpp
index 671d22cc66a0e9..b7922425a34e43 100644
--- a/lld/ELF/Target.cpp
+++ b/lld/ELF/Target.cpp
@@ -87,6 +87,8 @@ TargetInfo *elf::getTarget() {
     return getRISCVTargetInfo();
   case EM_SPARCV9:
     return getSPARCV9TargetInfo();
+  case EM_S390:
+    return getSystemZTargetInfo();
   case EM_X86_64:
     return getX86_64TargetInfo();
   }

diff  --git a/lld/ELF/Target.h b/lld/ELF/Target.h
index ab6b6b9c013ba3..3c06789cdbd361 100644
--- a/lld/ELF/Target.h
+++ b/lld/ELF/Target.h
@@ -186,6 +186,7 @@ TargetInfo *getPPC64TargetInfo();
 TargetInfo *getPPCTargetInfo();
 TargetInfo *getRISCVTargetInfo();
 TargetInfo *getSPARCV9TargetInfo();
+TargetInfo *getSystemZTargetInfo();
 TargetInfo *getX86TargetInfo();
 TargetInfo *getX86_64TargetInfo();
 template <class ELFT> TargetInfo *getMipsTargetInfo();

diff  --git a/lld/test/ELF/Inputs/systemz-init.s b/lld/test/ELF/Inputs/systemz-init.s
new file mode 100644
index 00000000000000..1611b69b4419e3
--- /dev/null
+++ b/lld/test/ELF/Inputs/systemz-init.s
@@ -0,0 +1,5 @@
+// glibc < 2.39 used to align .init and .fini code at a 4-byte boundary.
+// This file aims to recreate that behavior.
+	.section        .init,"ax", at progbits
+	.align	4
+	lg %r4, 272(%r15)

diff  --git a/lld/test/ELF/basic-systemz.s b/lld/test/ELF/basic-systemz.s
new file mode 100644
index 00000000000000..f7bb0e8cbd020d
--- /dev/null
+++ b/lld/test/ELF/basic-systemz.s
@@ -0,0 +1,63 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+# RUN: ld.lld --hash-style=sysv -discard-all -shared %t.o -o %t.so
+# RUN: llvm-readelf --file-header --program-headers --section-headers --dynamic-table %t.so | FileCheck %s
+
+# Exits with return code 55 on linux.
+.text
+  lghi 2,55
+  svc 1
+
+# CHECK:       ELF Header:
+# CHECK-NEXT:  Magic:   7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00
+# CHECK-NEXT:  Class:                             ELF64
+# CHECK-NEXT:  Data:                              2's complement, big endian
+# CHECK-NEXT:  Version:                           1 (current)
+# CHECK-NEXT:  OS/ABI:                            UNIX - System V
+# CHECK-NEXT:  ABI Version:                       0
+# CHECK-NEXT:  Type:                              DYN (Shared object file)
+# CHECK-NEXT:  Machine:                           IBM S/390
+# CHECK-NEXT:  Version:                           0x1
+# CHECK-NEXT:  Entry point address:               0x0
+# CHECK-NEXT:  Start of program headers:          64 (bytes into file)
+# CHECK-NEXT:  Start of section headers:          768 (bytes into file)
+# CHECK-NEXT:  Flags:                             0x0
+# CHECK-NEXT:  Size of this header:               64 (bytes)
+# CHECK-NEXT:  Size of program headers:           56 (bytes)
+# CHECK-NEXT:  Number of program headers:         7
+# CHECK-NEXT:  Size of section headers:           64 (bytes)
+# CHECK-NEXT:  Number of section headers:         11
+# CHECK-NEXT:  Section header string table index: 9
+
+# CHECK:       Section Headers:
+# CHECK-NEXT:  [Nr] Name              Type            Address          Off    Size   ES Flg Lk Inf Al
+# CHECK-NEXT:  [ 0]                   NULL            0000000000000000 000000 000000 00      0   0  0
+# CHECK-NEXT:  [ 1] .dynsym           DYNSYM          00000000000001c8 0001c8 000018 18   A  3   1  8
+# CHECK-NEXT:  [ 2] .hash             HASH            00000000000001e0 0001e0 000010 04   A  1   0  4
+# CHECK-NEXT:  [ 3] .dynstr           STRTAB          00000000000001f0 0001f0 000001 00   A  0   0  1
+# CHECK-NEXT:  [ 4] .text             PROGBITS        00000000000011f4 0001f4 000006 00  AX  0   0  4
+# CHECK-NEXT:  [ 5] .dynamic          DYNAMIC         0000000000002200 000200 000060 10  WA  3   0  8
+# CHECK-NEXT:  [ 6] .relro_padding    NOBITS          0000000000002260 000260 000da0 00  WA  0   0  1
+# CHECK-NEXT:  [ 7] .comment          PROGBITS        0000000000000000 000260 000008 01  MS  0   0  1
+# CHECK-NEXT:  [ 8] .symtab           SYMTAB          0000000000000000 000268 000030 18     10   2  8
+# CHECK-NEXT:  [ 9] .shstrtab         STRTAB          0000000000000000 000298 000058 00      0   0  1
+# CHECK-NEXT:  [10] .strtab           STRTAB          0000000000000000 0002f0 00000a 00      0   0  1
+
+# CHECK:       Program Headers:
+# CHECK-NEXT:  Type           Offset   VirtAddr           PhysAddr           FileSiz  MemSiz   Flg Align
+# CHECK-NEXT:  PHDR           0x000040 0x0000000000000040 0x0000000000000040 0x000188 0x000188 R   0x8
+# CHECK-NEXT:  LOAD           0x000000 0x0000000000000000 0x0000000000000000 0x0001f1 0x0001f1 R   0x1000
+# CHECK-NEXT:  LOAD           0x0001f4 0x00000000000011f4 0x00000000000011f4 0x000006 0x000006 R E 0x1000
+# CHECK-NEXT:  LOAD           0x000200 0x0000000000002200 0x0000000000002200 0x000060 0x000e00 RW  0x1000
+# CHECK-NEXT:  DYNAMIC        0x000200 0x0000000000002200 0x0000000000002200 0x000060 0x000060 RW  0x8
+# CHECK-NEXT:  GNU_RELRO      0x000200 0x0000000000002200 0x0000000000002200 0x000060 0x000e00 R   0x1
+# CHECK-NEXT:  GNU_STACK      0x000000 0x0000000000000000 0x0000000000000000 0x000000 0x000000 RW  0x0
+
+# CHECK:       Dynamic section at offset 0x200 contains 6 entries:
+# CHECK-NEXT:  Tag                Type     Name/Value
+# CHECK-NEXT:  0x0000000000000006 (SYMTAB) 0x1c8
+# CHECK-NEXT:  0x000000000000000b (SYMENT) 24 (bytes)
+# CHECK-NEXT:  0x0000000000000005 (STRTAB) 0x1f0
+# CHECK-NEXT:  0x000000000000000a (STRSZ)  1 (bytes)
+# CHECK-NEXT:  0x0000000000000004 (HASH)   0x1e0
+# CHECK-NEXT:  0x0000000000000000 (NULL)   0x0

diff  --git a/lld/test/ELF/emulation-systemz.s b/lld/test/ELF/emulation-systemz.s
new file mode 100644
index 00000000000000..dfdb4620954c8a
--- /dev/null
+++ b/lld/test/ELF/emulation-systemz.s
@@ -0,0 +1,29 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+# RUN: ld.lld -m elf64_s390 %t.o -o %t1
+# RUN: llvm-readelf --file-header %t1 | FileCheck %s
+# RUN: ld.lld %t.o -o %t2
+# RUN: llvm-readelf --file-header %t2 | FileCheck %s
+# RUN: echo 'OUTPUT_FORMAT(elf64-s390)' > %t.script
+# RUN: ld.lld %t.script %t.o -o %t3
+# RUN: llvm-readelf --file-header %t3 | FileCheck %s
+
+# CHECK:       ELF Header:
+# CHECK-NEXT:  Magic:   7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00
+# CHECK-NEXT:  Class:                             ELF64
+# CHECK-NEXT:  Data:                              2's complement, big endian
+# CHECK-NEXT:  Version:                           1 (current)
+# CHECK-NEXT:  OS/ABI:                            UNIX - System V
+# CHECK-NEXT:  ABI Version:                       0
+# CHECK-NEXT:  Type:                              EXEC (Executable file)
+# CHECK-NEXT:  Machine:                           IBM S/390
+# CHECK-NEXT:  Version:                           0x1
+# CHECK-NEXT:  Entry point address:
+# CHECK-NEXT:  Start of program headers:          64 (bytes into file)
+# CHECK-NEXT:  Start of section headers:
+# CHECK-NEXT:  Flags:                             0x0
+# CHECK-NEXT:  Size of this header:               64 (bytes)
+# CHECK-NEXT:  Size of program headers:           56 (bytes)
+
+.globl _start
+_start:

diff  --git a/lld/test/ELF/lto/systemz.ll b/lld/test/ELF/lto/systemz.ll
new file mode 100644
index 00000000000000..42bf4e32fb6d75
--- /dev/null
+++ b/lld/test/ELF/lto/systemz.ll
@@ -0,0 +1,18 @@
+; REQUIRES: systemz
+;; Test we can infer the e_machine value EM_S390 from a bitcode file.
+
+; RUN: llvm-as %s -o %t.o
+; RUN: ld.lld %t.o -o %t
+; RUN: llvm-readobj -h %t | FileCheck %s
+
+; CHECK: Class: 64-bit
+; CHECK: DataEncoding: BigEndian
+; CHECK: Machine: EM_S390
+
+target datalayout = "E-m:e-i1:8:16-i8:8:16-i64:64-f128:64-v128:64-a:8:16-n32:64"
+target triple = "s390x-unknown-linux-gnu"
+
+define void @_start() {
+entry:
+  ret void
+}

diff  --git a/lld/test/ELF/systemz-got.s b/lld/test/ELF/systemz-got.s
new file mode 100644
index 00000000000000..1d558aa3b02905
--- /dev/null
+++ b/lld/test/ELF/systemz-got.s
@@ -0,0 +1,16 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %p/Inputs/shared.s -o %t2.o
+# RUN: ld.lld -shared %t2.o -soname=%t2.so -o %t2.so
+
+# RUN: ld.lld -dynamic-linker /lib/ld64.so.1 %t.o %t2.so -o %t
+# RUN: llvm-readelf -S -r  %t | FileCheck %s
+
+# CHECK: .got              PROGBITS        {{.*}} {{.*}} 000020 00  WA  0   0  8
+
+# CHECK: Relocation section '.rela.dyn' at offset {{.*}} contains 1 entries:
+# CHECK: {{.*}}  000000010000000a R_390_GLOB_DAT         0000000000000000 bar + 0
+
+.global _start
+_start:
+	lgrl  %r1,bar at GOT

diff  --git a/lld/test/ELF/systemz-gotent-relax-align.s b/lld/test/ELF/systemz-gotent-relax-align.s
new file mode 100644
index 00000000000000..c6326086f56db0
--- /dev/null
+++ b/lld/test/ELF/systemz-gotent-relax-align.s
@@ -0,0 +1,48 @@
+# REQUIRES: systemz
+## Verify that R_390_GOTENT optimization is not performed on misaligned symbols.
+
+# RUN: llvm-mc -filetype=obj -relax-relocations -triple=s390x-unknown-linux %s -o %t.o
+# RUN: ld.lld %t.o -o %t1
+# RUN: llvm-readelf -S -r -x .got -x .got.plt %t1 | FileCheck --check-prefixes=CHECK %s
+# RUN: llvm-objdump --no-print-imm-hex -d %t1 | FileCheck --check-prefix=DISASM %s
+
+## We retain one .got entry for the unaligned symbol.
+# CHECK:      Name              Type            Address          Off    Size   ES Flg Lk Inf Al
+# CHECK:      .got              PROGBITS        00000000010021e0 0001e0 000020 00  WA  0   0  8
+# CHECK-NEXT: .relro_padding    NOBITS          0000000001002200 000200 000e00 00  WA  0   0  1
+# CHECK-NEXT: .data             PROGBITS        0000000001003200 000200 000006 00  WA  0   0  2
+
+# CHECK-LABEL: Hex dump of section '.got':
+# CHECK-NEXT:    0x010021e0 00000000 00000000 00000000 00000000
+# CHECK-NEXT:    0x010021f0 00000000 00000000 00000000 01003205
+
+# DISASM:      Disassembly of section .text:
+# DISASM:      <_start>:
+# DISASM-NEXT:   larl    %r1, 0x1003200
+# DISASM-NEXT:   larl    %r1, 0x1003200
+# DISASM-NEXT:   lgrl    %r1, 0x10021f8
+# DISASM-NEXT:   lgrl    %r1, 0x10021f8
+
+.data
+.globl var_align
+.hidden var_align
+ .align 2
+var_align:
+ .long 0
+
+.data
+.globl var_unalign
+.hidden var_unalign
+ .align 2
+ .byte 0
+var_unalign:
+ .byte 0
+
+.text
+.globl _start
+.type _start, @function
+_start:
+ lgrl %r1, var_align at GOT
+ lgrl %r1, var_align at GOT
+ lgrl %r1, var_unalign at GOT
+ lgrl %r1, var_unalign at GOT

diff  --git a/lld/test/ELF/systemz-gotent-relax-und-dso.s b/lld/test/ELF/systemz-gotent-relax-und-dso.s
new file mode 100644
index 00000000000000..57369a417fd445
--- /dev/null
+++ b/lld/test/ELF/systemz-gotent-relax-und-dso.s
@@ -0,0 +1,68 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -relax-relocations -triple=s390x-unknown-linux %s -o %t.o
+# RUN: llvm-mc -filetype=obj -relax-relocations -triple=s390x-unknown-linux %S/Inputs/gotpc-relax-und-dso.s -o %tdso.o
+# RUN: ld.lld -shared %tdso.o -soname=t.so -o %t.so
+# RUN: ld.lld --hash-style=sysv -shared %t.o %t.so -o %t
+# RUN: llvm-readelf -r %t | FileCheck --check-prefix=RELOC %s
+# RUN: llvm-objdump --no-print-imm-hex -d %t | FileCheck --check-prefix=DISASM %s
+
+# RELOC-LABEL: Relocation section '.rela.dyn' at offset {{.*}} contains 3 entries:
+# RELOC: 00000000000023f8 000000010000000a R_390_GLOB_DAT 00000000000012d8 foo + 0
+# RELOC: 0000000000002400 000000030000000a R_390_GLOB_DAT 0000000000000000 und + 0
+# RELOC: 0000000000002408 000000040000000a R_390_GLOB_DAT 0000000000000000 dsofoo + 0
+
+# DISASM:      Disassembly of section .text:
+# DISASM-EMPTY:
+# DISASM-NEXT: <foo>:
+# DISASM-NEXT:     bc 0, 0
+# DISASM:      <hid>:
+# DISASM-NEXT:     bc 0, 0
+# DISASM:      <_start>:
+# DISASM-NEXT:    lgrl    %r1, 0x2400
+# DISASM-NEXT:    lgrl    %r1, 0x2400
+# DISASM-NEXT:    lgrl    %r1, 0x2408
+# DISASM-NEXT:    lgrl    %r1, 0x2408
+# DISASM-NEXT:    larl    %r1, 0x12dc
+# DISASM-NEXT:    larl    %r1, 0x12dc
+# DISASM-NEXT:    lgrl    %r1, 0x23f8
+# DISASM-NEXT:    lgrl    %r1, 0x23f8
+# DISASM-NEXT:    lgrl    %r1, 0x2400
+# DISASM-NEXT:    lgrl    %r1, 0x2400
+# DISASM-NEXT:    lgrl    %r1, 0x2408
+# DISASM-NEXT:    lgrl    %r1, 0x2408
+# DISASM-NEXT:    larl    %r1, 0x12dc
+# DISASM-NEXT:    larl    %r1, 0x12dc
+# DISASM-NEXT:    lgrl    %r1, 0x23f8
+# DISASM-NEXT:    lgrl    %r1, 0x23f8
+
+.text
+.globl foo
+.type foo, @function
+foo:
+ nop
+
+.globl hid
+.hidden hid
+.type hid, @function
+hid:
+ nop
+
+.globl _start
+.type _start, @function
+_start:
+ lgrl %r1, und at GOT
+ lgrl %r1, und at GOT
+ lgrl %r1, dsofoo at GOT
+ lgrl %r1, dsofoo at GOT
+ lgrl %r1, hid at GOT
+ lgrl %r1, hid at GOT
+ lgrl %r1, foo at GOT
+ lgrl %r1, foo at GOT
+ lgrl %r1, und at GOT
+ lgrl %r1, und at GOT
+ lgrl %r1, dsofoo at GOT
+ lgrl %r1, dsofoo at GOT
+ lgrl %r1, hid at GOT
+ lgrl %r1, hid at GOT
+ lgrl %r1, foo at GOT
+ lgrl %r1, foo at GOT

diff  --git a/lld/test/ELF/systemz-gotent-relax.s b/lld/test/ELF/systemz-gotent-relax.s
new file mode 100644
index 00000000000000..f665e1af9e53d2
--- /dev/null
+++ b/lld/test/ELF/systemz-gotent-relax.s
@@ -0,0 +1,91 @@
+# REQUIRES: systemz
+## Test R_390_GOTENT optimization.
+
+# RUN: llvm-mc -filetype=obj -relax-relocations -triple=s390x-unknown-linux %s -o %t.o
+# RUN: ld.lld %t.o -o %t1 --no-apply-dynamic-relocs
+# RUN: llvm-readelf -S -r -x .got.plt %t1 | FileCheck --check-prefixes=CHECK,NOAPPLY %s
+# RUN: ld.lld %t.o -o %t1 --apply-dynamic-relocs
+# RUN: llvm-readelf -S -r -x .got.plt %t1 | FileCheck --check-prefixes=CHECK,APPLY %s
+# RUN: ld.lld %t.o -o %t1
+# RUN: llvm-objdump --no-print-imm-hex -d %t1 | FileCheck --check-prefix=DISASM %s
+
+## --no-relax disables GOT optimization.
+# RUN: ld.lld --no-relax %t.o -o %t2
+# RUN: llvm-objdump --no-print-imm-hex -d %t2 | FileCheck --check-prefix=NORELAX %s
+
+## In our implementation, .got is retained even if all GOT-generating relocations are optimized.
+# CHECK:      Name              Type            Address          Off    Size   ES Flg Lk Inf Al
+# CHECK:      .iplt             PROGBITS        0000000001001240 000240 000020 00  AX  0   0 16
+# CHECK-NEXT: .got              PROGBITS        0000000001002260 000260 000018 00  WA  0   0  8
+# CHECK-NEXT: .relro_padding    NOBITS          0000000001002278 000278 000d88 00  WA  0   0  1
+# CHECK-NEXT: .got.plt          PROGBITS        0000000001003278 000278 000008 00  WA  0   0  8
+
+## There is one R_S390_IRELATIVE relocation.
+# CHECK-LABEL: Relocation section '.rela.dyn' at offset {{.*}} contains 1 entries:
+# CHECK:       0000000001003278  000000000000003d R_390_IRELATIVE                   10011e8
+
+# CHECK-LABEL: Hex dump of section '.got.plt':
+# NOAPPLY-NEXT:  0x01003278 00000000 00000000
+# APPLY-NEXT:    0x01003278 00000000 010011e8
+
+# DISASM:      Disassembly of section .text:
+# DISASM: 00000000010011e0 <foo>:
+# DISASM-NEXT:   bc      0, 0
+# DISASM: 00000000010011e4 <hid>:
+# DISASM-NEXT:   bc      0, 0
+# DISASM: 00000000010011e8 <ifunc>:
+# DISASM-NEXT:   br      %r14
+# DISASM: 00000000010011ea <_start>:
+# DISASM-NEXT:   larl    %r1, 0x10011e0
+# DISASM-NEXT:   larl    %r1, 0x10011e0
+# DISASM-NEXT:   larl    %r1, 0x10011e4
+# DISASM-NEXT:   larl    %r1, 0x10011e4
+# DISASM-NEXT:   lgrl    %r1, 0x1003278
+# DISASM-NEXT:   lgrl    %r1, 0x1003278
+# DISASM-NEXT:   larl    %r1, 0x10011e0
+# DISASM-NEXT:   larl    %r1, 0x10011e0
+# DISASM-NEXT:   larl    %r1, 0x10011e4
+# DISASM-NEXT:   larl    %r1, 0x10011e4
+# DISASM-NEXT:   lgrl    %r1, 0x1003278
+# DISASM-NEXT:   lgrl    %r1, 0x1003278
+
+# NORELAX-LABEL: <_start>:
+# NORELAX-COUNT-12: lgrl
+
+.text
+.globl foo
+
+.text
+.globl foo
+.type foo, @function
+foo:
+ nop
+
+.globl hid
+.hidden hid
+.type hid, @function
+hid:
+ nop
+
+.text
+.type ifunc STT_GNU_IFUNC
+.globl ifunc
+.type ifunc, @function
+ifunc:
+ br %r14
+
+.globl _start
+.type _start, @function
+_start:
+ lgrl %r1, foo at GOT
+ lgrl %r1, foo at GOT
+ lgrl %r1, hid at GOT
+ lgrl %r1, hid at GOT
+ lgrl %r1, ifunc at GOT
+ lgrl %r1, ifunc at GOT
+ lgrl %r1, foo at GOT
+ lgrl %r1, foo at GOT
+ lgrl %r1, hid at GOT
+ lgrl %r1, hid at GOT
+ lgrl %r1, ifunc at GOT
+ lgrl %r1, ifunc at GOT

diff  --git a/lld/test/ELF/systemz-ifunc-nonpreemptible.s b/lld/test/ELF/systemz-ifunc-nonpreemptible.s
new file mode 100644
index 00000000000000..5056db302ca1c7
--- /dev/null
+++ b/lld/test/ELF/systemz-ifunc-nonpreemptible.s
@@ -0,0 +1,75 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-none-linux-gnu %s -o %t.o
+# RUN: ld.lld -static %t.o -o %t
+# RUN: ld.lld -static %t.o -o %t.apply --apply-dynamic-relocs
+# RUN: llvm-readelf --section-headers --relocations --symbols %t | FileCheck %s
+# RUN: llvm-readelf -x .got.plt %t | FileCheck %s --check-prefix=NO-APPLY-RELOC
+# RUN: llvm-readelf -x .got.plt %t.apply | FileCheck %s --check-prefix=APPLY-RELOC
+# RUN: llvm-objdump --no-print-imm-hex -d --no-show-raw-insn %t | FileCheck %s --check-prefix=DISASM
+
+# CHECK:      Section Headers:
+# CHECK-NEXT:  [Nr] Name              Type            Address          Off    Size   ES Flg Lk Inf Al
+# CHECK-NEXT:  [ 0]                   NULL            0000000000000000 000000 000000 00      0   0  0
+# CHECK-NEXT:  [ 1] .rela.dyn         RELA            0000000001000158 000158 000030 18  AI  0   4  8
+# CHECK-NEXT:  [ 2] .text             PROGBITS        0000000001001188 000188 00001c 00  AX  0   0  4
+# CHECK-NEXT:  [ 3] .iplt             PROGBITS        00000000010011b0 0001b0 000040 00  AX  0   0 16
+# CHECK-NEXT:  [ 4] .got.plt          PROGBITS        00000000010021f0 0001f0 000010 00  WA  0   0  8
+
+# CHECK:      Relocation section '.rela.dyn' at offset 0x158 contains 2 entries:
+# CHECK-NEXT:     Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
+# CHECK-NEXT: 00000000010021f0  000000000000003d R_390_IRELATIVE                   1001188
+# CHECK-NEXT: 00000000010021f8  000000000000003d R_390_IRELATIVE                   100118a
+
+# CHECK:      Symbol table '.symtab' contains 6 entries:
+# CHECK-NEXT:   Num:    Value          Size Type    Bind   Vis       Ndx Name
+# CHECK-NEXT:     0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT   UND
+# CHECK-NEXT:     1: 0000000001000158     0 NOTYPE  LOCAL  HIDDEN      1 __rela_iplt_start
+# CHECK-NEXT:     2: 0000000001000188     0 NOTYPE  LOCAL  HIDDEN      1 __rela_iplt_end
+# CHECK-NEXT:     3: 0000000001001188     0 IFUNC   GLOBAL DEFAULT     2 foo
+# CHECK-NEXT:     4: 000000000100118a     0 IFUNC   GLOBAL DEFAULT     2 bar
+# CHECK-NEXT:     5: 000000000100118c     0 NOTYPE  GLOBAL DEFAULT     2 _start
+
+# NO-APPLY-RELOC-LABEL:  Hex dump of section '.got.plt':
+# NO-APPLY-RELOC-NEXT:     0x010021f0 00000000 00000000 00000000 00000000
+# NO-APPLY-RELOC-EMPTY:
+
+# APPLY-RELOC-LABEL:  Hex dump of section '.got.plt':
+# APPLY-RELOC-NEXT:     0x010021f0 00000000 01001188 00000000 0100118a
+# APPLY-RELOC-EMPTY:
+
+# DISASM: Disassembly of section .text:
+# DISASM: 0000000001001188 <foo>:
+# DISASM-NEXT:  br      %r14
+# DISASM: 000000000100118a <bar>:
+# DISASM-NEXT:  br      %r14
+# DISASM: 000000000100118c  <_start>:
+# DISASM-NEXT:  brasl   %r14, 0x10011b0
+# DISASM-NEXT:  brasl   %r14, 0x10011d0
+# DISASM-NEXT:  larl    %r2, 0x1000158
+# DISASM-NEXT:  larl    %r2, 0x1000188
+# DISASM: Disassembly of section .iplt:
+# DISASM: <.iplt>:
+# DISASM:        10011b0:       larl    %r1, 0x10021f0
+# DISASM-NEXT:   10011b6:       lg      %r1, 0(%r1)
+# DISASM-NEXT:   10011bc:       br      %r1
+# DISASM:        10011d0:       larl    %r1, 0x10021f8
+# DISASM-NEXT:   10011d6:       lg      %r1, 0(%r1)
+# DISASM-NEXT:   10011dc:       br      %r1
+
+.text
+.type foo STT_GNU_IFUNC
+.globl foo
+foo:
+ br %r14
+
+.type bar STT_GNU_IFUNC
+.globl bar
+bar:
+ br %r14
+
+.globl _start
+_start:
+ brasl %r14, foo at plt
+ brasl %r14, bar at plt
+ larl %r2, __rela_iplt_start
+ larl %r2, __rela_iplt_end

diff  --git a/lld/test/ELF/systemz-init-padding.s b/lld/test/ELF/systemz-init-padding.s
new file mode 100644
index 00000000000000..c56b98d43f1b0e
--- /dev/null
+++ b/lld/test/ELF/systemz-init-padding.s
@@ -0,0 +1,27 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %p/Inputs/systemz-init.s -o systemz-init.o
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+# RUN: ld.lld -dynamic-linker /lib/ld64.so.1 %t.o systemz-init.o -o %t
+# RUN: llvm-objdump -d --no-show-raw-insn -j .init %t | FileCheck %s
+
+# glibc < 2.39 used to align .init and .fini code at a 4-byte boundary.
+# When that happens, the linker must not pad the code with invalid
+# instructions, e.g. null bytes.
+	.section        .init,"ax", at progbits
+	brasl %r14, startup
+
+# CHECK:      <.init>:
+# CHECK-NEXT: brasl %r14,
+# CHECK-NEXT: bcr     0, %r7
+# CHECK-NEXT: lg %r4, 272(%r15)
+
+	.text
+	.globl startup
+	.p2align 4
+startup:
+	br %r14
+
+	.globl main
+	.p2align 4
+main:
+	br %r14

diff  --git a/lld/test/ELF/systemz-pie.s b/lld/test/ELF/systemz-pie.s
new file mode 100644
index 00000000000000..bb971a82fb8ced
--- /dev/null
+++ b/lld/test/ELF/systemz-pie.s
@@ -0,0 +1,38 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t1.o
+
+## Check -pie.
+# RUN: ld.lld -pie %t1.o -o %t
+# RUN: llvm-readelf --file-headers --program-headers --dynamic %t | FileCheck %s
+
+# CHECK: ELF Header:
+# CHECK-NEXT:  Magic:   7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00
+# CHECK-NEXT:  Class:                             ELF64
+# CHECK-NEXT:  Data:                              2's complement, big endian
+# CHECK-NEXT:  Version:                           1 (current)
+# CHECK-NEXT:  OS/ABI:                            UNIX - System V
+# CHECK-NEXT:  ABI Version:                       0
+# CHECK-NEXT:  Type:                              DYN (Shared object file)
+# CHECK-NEXT:  Machine:                           IBM S/390
+# CHECK-NEXT:  Version:                           0x1
+
+# CHECK: Program Headers:
+# CHECK-NEXT:  Type           Offset   VirtAddr           PhysAddr           FileSiz  MemSiz   Flg Align
+# CHECK-NEXT:  PHDR           0x000040 0x0000000000000040 0x0000000000000040 0x000188 0x000188 R   0x8
+# CHECK-NEXT:  LOAD           0x000000 0x0000000000000000 0x0000000000000000 0x00020d 0x00020d R   0x1000
+# CHECK-NEXT:  LOAD           0x000210 0x0000000000002210 0x0000000000002210 0x000090 0x000df0 RW  0x1000
+# CHECK-NEXT:  DYNAMIC        0x000210 0x0000000000002210 0x0000000000002210 0x000090 0x000090 RW  0x8
+# CHECK-NEXT:  GNU_RELRO      0x000210 0x0000000000002210 0x0000000000002210 0x000090 0x000df0 R   0x1
+# CHECK-NEXT:  GNU_STACK      0x000000 0x0000000000000000 0x0000000000000000 0x000000 0x000000 RW  0x0
+
+# CHECK: Dynamic section at offset 0x210 contains 9 entries:
+# CHECK-NEXT:   Tag                Type       Name/Value
+# CHECK-NEXT:   0x000000006ffffffb (FLAGS_1)  PIE
+
+## Check -nopie
+# RUN: ld.lld -no-pie %t1.o -o %t2
+# RUN: llvm-readelf --file-headers %t2 | FileCheck %s --check-prefix=NOPIE
+# NOPIE-NOT: Type: DYN
+
+.globl _start
+_start:

diff  --git a/lld/test/ELF/systemz-plt.s b/lld/test/ELF/systemz-plt.s
new file mode 100644
index 00000000000000..4669f01f588121
--- /dev/null
+++ b/lld/test/ELF/systemz-plt.s
@@ -0,0 +1,83 @@
+# REQUIRES: systemz
+# RUN: echo '.globl bar, weak; .type bar, at function; .type weak, at function; bar: weak:' > %t1.s
+
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %t1.s -o %t1.o
+# RUN: ld.lld -shared %t1.o -soname=t1.so -o %t1.so
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+# RUN: ld.lld %t.o %t1.so -z separate-code -o %t
+# RUN: llvm-readelf -S -s -r -x .got.plt %t | FileCheck %s
+# RUN: llvm-objdump -d %t | FileCheck --check-prefixes=DIS %s
+
+# CHECK: Section Headers:
+# CHECK: .plt     PROGBITS 0000000001001020 001020 000060 00  AX  0   0 16
+# CHECK: .got     PROGBITS 00000000010020d0 0020d0 000018 00  WA  0   0  8
+# CHECK: .got.plt PROGBITS 00000000010030e8 0020e8 000010 00  WA  0   0  8
+
+# CHECK: Relocation section '.rela.plt' at offset {{.*}} contains 2 entries:
+# CHECK: 00000000010030e8 000000010000000b R_390_JMP_SLOT 0000000000000000 bar + 0
+# CHECK: 00000000010030f0 000000020000000b R_390_JMP_SLOT 0000000000000000 weak + 0
+
+## A canonical PLT has a non-zero st_value. bar and weak are called but their
+## addresses are not taken, so a canonical PLT is not necessary.
+# CHECK: Symbol table '.dynsym' contains 3 entries:
+# CHECK-NEXT:   Num:    Value          Size Type    Bind   Vis       Ndx Name
+# CHECK-NEXT:     0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT   UND
+# CHECK-NEXT:     1: 0000000000000000     0 FUNC    GLOBAL DEFAULT   UND bar
+# CHECK-NEXT:     2: 0000000000000000     0 FUNC    WEAK   DEFAULT   UND weak
+
+## The .got.plt slots relocated by .rela.plt point to .plt
+## This is required by glibc.
+# CHECK: Hex dump of section '.got.plt':
+# CHECK-NEXT: 0x010030e8 00000000 0100104e 00000000 0100106e
+
+# DIS: Disassembly of section .text:
+
+# DIS: 0000000001001000 <_start>:
+# DIS-NEXT: brasl	%r14, 0x1001012
+# DIS-NEXT: brasl	%r14, 0x1001040
+# DIS-NEXT: brasl	%r14, 0x1001060
+
+# DIS: 0000000001001012 <foo>:
+# DIS-NEXT: br	%r14
+
+# DIS: Disassembly of section .plt:
+
+# DIS: 0000000001001020 <.plt>:
+# DIS-NEXT: 1001020: e3 10 f0 38 00 24    	stg	%r1, 56(%r15)
+# DIS-NEXT: 1001026: c0 10 00 00 08 55          larl	%r1, 0x10020d0
+# DIS-NEXT: 100102c: d2 07 f0 30 10 08    	mvc	48(8,%r15), 8(%r1)
+# DIS-NEXT: 1001032: e3 10 10 10 00 04    	lg	%r1, 16(%r1)
+# DIS-NEXT: 1001038: 07 f1        	br	%r1
+# DIS-NEXT: 100103a: 07 00        	bcr	0, %r0
+# DIS-NEXT: 100103c: 07 00        	bcr	0, %r0
+# DIS-NEXT: 100103e: 07 00        	bcr	0, %r0
+# DIS-NEXT: 1001040: c0 10 00 00 10 54    	larl	%r1, 0x10030e8
+# DIS-NEXT: 1001046: e3 10 10 00 00 04    	lg	%r1, 0(%r1)
+# DIS-NEXT: 100104c: 07 f1        	br	%r1
+# DIS-NEXT: 100104e: 0d 10        	basr	%r1, 0
+# DIS-NEXT: 1001050: e3 10 10 0c 00 14    	lgf	%r1, 12(%r1)
+# DIS-NEXT: 1001056: c0 f4 ff ff ff e5    	jg	0x1001020
+# DIS-NEXT: 100105c: 00 00        	<unknown>
+# DIS-NEXT: 100105e: 00 00        	<unknown>
+# DIS-NEXT: 1001060: c0 10 00 00 10 48    	larl	%r1, 0x10030f0
+# DIS-NEXT: 1001066: e3 10 10 00 00 04    	lg	%r1, 0(%r1)
+# DIS-NEXT: 100106c: 07 f1        	br	%r1
+# DIS-NEXT: 100106e: 0d 10        	basr	%r1, 0
+# DIS-NEXT: 1001070: e3 10 10 0c 00 14    	lgf	%r1, 12(%r1)
+# DIS-NEXT: 1001076: c0 f4 ff ff ff d5    	jg	0x1001020
+# DIS-NEXT: 100107c: 00 00        	<unknown>
+# DIS-NEXT: 100107e: 00 18        	<unknown>
+
+.global _start, foo, bar
+.weak weak
+
+_start:
+  ## Use @plt to avoid generating direct references that would force
+  ## allocation of a canonical PLT entry.
+  brasl %r14, foo at plt
+  brasl %r14, bar at plt
+  brasl %r14, weak at plt
+
+## foo is local and non-preemptable, no PLT is generated.
+foo:
+  br %r14

diff  --git a/lld/test/ELF/systemz-reloc-abs.s b/lld/test/ELF/systemz-reloc-abs.s
new file mode 100644
index 00000000000000..b5ad94d90d3a96
--- /dev/null
+++ b/lld/test/ELF/systemz-reloc-abs.s
@@ -0,0 +1,32 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x %s -o %t.o
+# RUN: llvm-mc -filetype=obj -triple=s390x %S/Inputs/abs255.s -o %t255.o
+# RUN: llvm-mc -filetype=obj -triple=s390x %S/Inputs/abs256.s -o %t256.o
+# RUN: llvm-mc -filetype=obj -triple=s390x %S/Inputs/abs257.s -o %t257.o
+
+# RUN: ld.lld %t.o %t256.o -o %t
+# RUN: llvm-readelf -x .data %t | FileCheck %s
+# CHECK: 0x{{[0-9a-f]+}} ff80ffff 8000ffff ffff8000 0000ffff
+# CHECK-NEXT:            ffffffff ffff8000 00000000 0000
+
+# RUN: not ld.lld %t.o %t255.o -o /dev/null 2>&1 | FileCheck --check-prefix=OVERFLOW1 %s
+# OVERFLOW1: relocation R_390_8 out of range: -129 is not in [-128, 255]
+# OVERFLOW1: relocation R_390_16 out of range: -32769 is not in [-32768, 65535]
+# OVERFLOW1: relocation R_390_32 out of range: -2147483649 is not in [-2147483648, 4294967295]
+
+# RUN: not ld.lld %t.o %t257.o -o /dev/null 2>&1 | FileCheck --check-prefix=OVERFLOW2 %s
+# OVERFLOW2: relocation R_390_8 out of range: 256 is not in [-128, 255]
+# OVERFLOW2: relocation R_390_16 out of range: 65536 is not in [-32768, 65535]
+# OVERFLOW2: relocation R_390_32 out of range: 4294967296 is not in [-2147483648, 4294967295]
+
+.globl _start
+_start:
+.data
+.byte foo - 1
+.byte foo - 384
+.word foo + 0xfeff
+.word foo - 0x8100
+.long foo + 0xfffffeff
+.long foo - 0x80000100
+.quad foo + 0xfffffffffffffeff
+.quad foo - 0x8000000000000100

diff  --git a/lld/test/ELF/systemz-reloc-disp12.s b/lld/test/ELF/systemz-reloc-disp12.s
new file mode 100644
index 00000000000000..3d32707d149fe7
--- /dev/null
+++ b/lld/test/ELF/systemz-reloc-disp12.s
@@ -0,0 +1,21 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym DISP=291 %s -o %t1.o
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym DISP=4095 %s -o %t2.o
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym DISP=4096 %s -o %t3.o
+
+# RUN: ld.lld --section-start=.text=0x0 %t1.o -o %t1out
+# RUN: ld.lld --section-start=.text=0x0 %t2.o -o %t2out
+# RUN: not ld.lld --section-start=.text=0x0 %t3.o -o /dev/null 2>&1 | FileCheck %s --check-prefix RANGE
+
+# RANGE: relocation R_390_12 out of range: 4096 is not in [0, 4095]
+
+# RUN: llvm-readelf --hex-dump=.text %t1out | FileCheck %s -DINSN=58678123 --check-prefix DUMP
+# RUN: llvm-readelf --hex-dump=.text %t2out | FileCheck %s -DINSN=58678fff --check-prefix DUMP
+
+# DUMP:  0x00000000 [[INSN]]
+
+.text
+.globl _start
+_start:
+    .reloc .+2, R_390_12, DISP
+    l %r6, 0(%r7,%r8)

diff  --git a/lld/test/ELF/systemz-reloc-disp20.s b/lld/test/ELF/systemz-reloc-disp20.s
new file mode 100644
index 00000000000000..88cd657c6ae3cb
--- /dev/null
+++ b/lld/test/ELF/systemz-reloc-disp20.s
@@ -0,0 +1,21 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym DISP=74565 %s -o %t1.o
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym DISP=524287 %s -o %t2.o
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym DISP=524288 %s -o %t3.o
+
+# RUN: ld.lld --section-start=.text=0x0 %t1.o -o %t1out
+# RUN: ld.lld --section-start=.text=0x0 %t2.o -o %t2out
+# RUN: not ld.lld --section-start=.text=0x0 %t3.o -o /dev/null 2>&1 | FileCheck %s --check-prefix RANGE
+
+# RANGE: relocation R_390_20 out of range: 524288 is not in [-524288, 524287]
+
+# RUN: llvm-readelf --hex-dump=.text %t1out | FileCheck %s -DINSN="e3678345 1204" --check-prefix DUMP
+# RUN: llvm-readelf --hex-dump=.text %t2out | FileCheck %s -DINSN="e3678fff 7f04" --check-prefix DUMP
+
+# DUMP:  0x00000000 [[INSN]]
+
+.text
+.globl _start
+_start:
+    .reloc .+2, R_390_20, DISP
+    lg %r6, 0(%r7,%r8)

diff  --git a/lld/test/ELF/systemz-reloc-got.s b/lld/test/ELF/systemz-reloc-got.s
new file mode 100644
index 00000000000000..4b9ac16481f4cb
--- /dev/null
+++ b/lld/test/ELF/systemz-reloc-got.s
@@ -0,0 +1,92 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+# RUN: ld.lld -z norelro -shared %t.o -soname=t.so -o %t.so
+## Note: Without norelro the distance between .got and .got.plt causes
+## R_390_GOTPLT12 relocations to always overflow.
+
+# RUN: llvm-readelf -S -x .data %t.so | FileCheck %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t.so | FileCheck %s --check-prefix=DISASM
+
+# CHECK: Section Headers:
+# CHECK: .got PROGBITS 0000000000002458
+# CHECK: .got.plt PROGBITS 0000000000002480
+
+## Note: _GLOBAL_OFFSET_TABLE is at .got
+## GOT (foo) is at .got + 24 == 0x2470
+## GOT (bar) is at .got + 32 == 0x2478
+## GOTPLT (foo) is at .got.plt + 0 == .got + 40 == 0x2480
+## GOTPLT (bar) is at .got.plt + 8 == .got + 48 == 0x2488
+
+# DISASM:      larl %r12, 0x2458
+# DISASM-NEXT: larl %r1, 0x2470
+# DISASM-NEXT: larl %r1, 0x2478
+# DISASM-NEXT: larl %r1, 0x2480
+# DISASM-NEXT: larl %r1, 0x2488
+
+# DISASM-NEXT: l %r1, 24(%r12)
+# DISASM-NEXT: l %r1, 32(%r12)
+# DISASM-NEXT: l %r1, 40(%r12)
+# DISASM-NEXT: l %r1, 48(%r12)
+# DISASM-NEXT: lg %r1, 24(%r12)
+# DISASM-NEXT: lg %r1, 32(%r12)
+# DISASM-NEXT: lg %r1, 40(%r12)
+# DISASM-NEXT: lg %r1, 48(%r12)
+
+# CHECK: Hex dump of section '.data':
+# CHECK-NEXT: 00180020 00280030 00000018 00000020
+# CHECK-NEXT: 00000028 00000030 00000000 00000018
+# CHECK-NEXT: 00000000 00000020 00000000 00000028
+# CHECK-NEXT: 00000000 00000030
+
+.text
+larl %r12, _GLOBAL_OFFSET_TABLE_
+.reloc .+2, R_390_GOTENT, foo+2
+larl %r1, 0
+.reloc .+2, R_390_GOTENT, bar+2
+larl %r1, 0
+.reloc .+2, R_390_GOTPLTENT, foo+2
+larl %r1, 0
+.reloc .+2, R_390_GOTPLTENT, bar+2
+larl %r1, 0
+.reloc .+2, R_390_GOT12, foo
+l %r1, 0(%r12)
+.reloc .+2, R_390_GOT12, bar
+l %r1, 0(%r12)
+.reloc .+2, R_390_GOTPLT12, foo
+l %r1, 0(%r12)
+.reloc .+2, R_390_GOTPLT12, bar
+l %r1, 0(%r12)
+.reloc .+2, R_390_GOT20, foo
+lg %r1, 0(%r12)
+.reloc .+2, R_390_GOT20, bar
+lg %r1, 0(%r12)
+.reloc .+2, R_390_GOTPLT20, foo
+lg %r1, 0(%r12)
+.reloc .+2, R_390_GOTPLT20, bar
+lg %r1, 0(%r12)
+
+.data
+.reloc ., R_390_GOT16, foo
+.space 2
+.reloc ., R_390_GOT16, bar
+.space 2
+.reloc ., R_390_GOTPLT16, foo
+.space 2
+.reloc ., R_390_GOTPLT16, bar
+.space 2
+.reloc ., R_390_GOT32, foo
+.space 4
+.reloc ., R_390_GOT32, bar
+.space 4
+.reloc ., R_390_GOTPLT32, foo
+.space 4
+.reloc ., R_390_GOTPLT32, bar
+.space 4
+.reloc ., R_390_GOT64, foo
+.space 8
+.reloc ., R_390_GOT64, bar
+.space 8
+.reloc ., R_390_GOTPLT64, foo
+.space 8
+.reloc ., R_390_GOTPLT64, bar
+.space 8

diff  --git a/lld/test/ELF/systemz-reloc-gotrel.s b/lld/test/ELF/systemz-reloc-gotrel.s
new file mode 100644
index 00000000000000..46669ecfa7fd01
--- /dev/null
+++ b/lld/test/ELF/systemz-reloc-gotrel.s
@@ -0,0 +1,36 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+# RUN: ld.lld -shared %t.o -soname=t.so -o %t.so
+
+# RUN: llvm-readelf -S -s -x .data %t.so | FileCheck %s
+
+# CHECK: Section Headers:
+# CHECK: .plt PROGBITS 0000000000001290
+# CHECK: .got PROGBITS 0000000000002390
+
+# CHECK: Symbol table '.symtab'
+# CHECK: 0000000000001288 {{.*}}  bar
+
+## Note: foo is the first (and only) PLT entry, which resides at .plt + 32
+## PLTOFF (foo) is (.plt + 32) - .got == 0x12b0 - 0x2390 == 0xffffef20
+## GOTOFF (bar) is bar - .got == 0x1288 - 0x2390 == 0xffffeef8
+# CHECK: Hex dump of section '.data':
+# CHECK-NEXT: eef8ef20 ffffeef8 ffffef20 ffffffff
+# CHECK-NEXT: ffffeef8 ffffffff ffffef20
+
+bar:
+  br %r14
+
+.data
+.reloc ., R_390_GOTOFF16, bar
+.space 2
+.reloc ., R_390_PLTOFF16, foo
+.space 2
+.reloc ., R_390_GOTOFF, bar
+.space 4
+.reloc ., R_390_PLTOFF32, foo
+.space 4
+.reloc ., R_390_GOTOFF64, bar
+.space 8
+.reloc ., R_390_PLTOFF64, foo
+.space 8

diff  --git a/lld/test/ELF/systemz-reloc-pc16.s b/lld/test/ELF/systemz-reloc-pc16.s
new file mode 100644
index 00000000000000..e1dad5af239d45
--- /dev/null
+++ b/lld/test/ELF/systemz-reloc-pc16.s
@@ -0,0 +1,39 @@
+# REQUIRES: systemz
+# RUN: rm -rf %t && split-file %s %t
+
+## Check recompile with -fPIC error message
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %t/shared.s -o %t/shared.o
+# RUN: not ld.lld -shared %t/shared.o -o /dev/null 2>&1 | FileCheck %s
+
+# CHECK: error: relocation R_390_PC16 cannot be used against symbol '_shared'; recompile with -fPIC
+# CHECK: >>> defined in {{.*}}
+# CHECK: >>> referenced by {{.*}}:(.data+0x1)
+
+## Check patching of negative addends
+
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym ADDEND=1 %t/addend.s -o %t/1.o
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym ADDEND=32768 %t/addend.s -o %t/2.o
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym ADDEND=32769 %t/addend.s -o %t/3.o
+
+# RUN: ld.lld --section-start=.text=0x0 %t/1.o -o %t/1out
+# RUN: ld.lld --section-start=.text=0x0 %t/2.o -o %t/2out
+# RUN: not ld.lld --section-start=.text=0x0 %t/3.o -o /dev/null 2>&1 | FileCheck %s -DFILE=%t/3.o --check-prefix RANGE
+
+# RANGE: error: [[FILE]]:(.text+0x0): relocation R_390_PC16 out of range
+
+# RUN: llvm-readelf --hex-dump=.text %t/1out | FileCheck %s -DADDEND=ffff --check-prefix DUMP
+# RUN: llvm-readelf --hex-dump=.text %t/2out | FileCheck %s -DADDEND=8000 --check-prefix DUMP
+
+# DUMP:  0x00000000 [[ADDEND]]
+
+#--- shared.s
+.data
+ .byte 0xe8
+ .word _shared - .
+
+#--- addend.s
+.text
+.globl _start
+_start:
+    .reloc ., R_390_PC16, .text-ADDEND
+    .space 2

diff  --git a/lld/test/ELF/systemz-reloc-pc32.s b/lld/test/ELF/systemz-reloc-pc32.s
new file mode 100644
index 00000000000000..0cb9322eb1c1b9
--- /dev/null
+++ b/lld/test/ELF/systemz-reloc-pc32.s
@@ -0,0 +1,39 @@
+# REQUIRES: systemz
+# RUN: rm -rf %t && split-file %s %t
+
+## Check recompile with -fPIC error message
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %t/shared.s -o %t/shared.o
+# RUN: not ld.lld -shared %t/shared.o -o /dev/null 2>&1 | FileCheck %s
+
+# CHECK: error: relocation R_390_PC32 cannot be used against symbol '_shared'; recompile with -fPIC
+# CHECK: >>> defined in {{.*}}
+# CHECK: >>> referenced by {{.*}}:(.data+0x1)
+
+## Check patching of negative addends
+
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym ADDEND=1 %t/addend.s -o %t/1.o
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym ADDEND=2147483648 %t/addend.s -o %t/2.o
+# RUN: llvm-mc -filetype=obj -triple=s390x -defsym ADDEND=2147483649 %t/addend.s -o %t/3.o
+
+# RUN: ld.lld --section-start=.text=0x0 %t/1.o -o %t/1out
+# RUN: ld.lld --section-start=.text=0x0 %t/2.o -o %t/2out
+# RUN: not ld.lld --section-start=.text=0x0 %t/3.o -o /dev/null 2>&1 | FileCheck %s -DFILE=%t/3.o --check-prefix RANGE
+
+# RANGE: error: [[FILE]]:(.text+0x0): relocation R_390_PC32 out of range
+
+# RUN: llvm-readelf --hex-dump=.text %t/1out | FileCheck %s -DADDEND=ffffffff --check-prefix DUMP
+# RUN: llvm-readelf --hex-dump=.text %t/2out | FileCheck %s -DADDEND=80000000 --check-prefix DUMP
+
+# DUMP:  0x00000000 [[ADDEND]]
+
+#--- shared.s
+.data
+ .byte 0xe8
+ .long _shared - .
+
+#--- addend.s
+.text
+.globl _start
+_start:
+    .reloc ., R_390_PC32, .text-ADDEND
+    .space 4

diff  --git a/lld/test/ELF/systemz-reloc-pcdbl.s b/lld/test/ELF/systemz-reloc-pcdbl.s
new file mode 100644
index 00000000000000..faee756f5e95b4
--- /dev/null
+++ b/lld/test/ELF/systemz-reloc-pcdbl.s
@@ -0,0 +1,68 @@
+# REQUIRES: systemz
+
+# RUN: llvm-mc --filetype=obj --triple=s390x-unknown-linux -mcpu=z13 %s -o %t.o
+
+# RUN: ld.lld %t.o --defsym foo16=pc16dbl+4 --defsym bar16=pc16dbl --defsym foo32=pc32dbl+6 --defsym bar32=pc32dbl --defsym foo12=pc12dbl+6 --defsym bar12=pc12dbl --defsym foo24=pc24dbl+6 --defsym bar24=pc24dbl -o %t
+# RUN: llvm-objdump --no-show-raw-insn --mcpu=z13 -d %t | FileCheck %s --check-prefix=CHECK
+# CHECK: 0000000001001120 <pc16dbl>:
+# CHECK: je      0x1001124
+# CHECK: jne     0x1001120
+# CHECK: 0000000001001128 <pc32dbl>:
+# CHECK: jge     0x100112e
+# CHECK: jgne    0x1001128
+# CHECK: 0000000001001134 <pc12dbl>:
+# CHECK: bprp    5, 0x100113a, 0x1001134
+# CHECK: bprp    6, 0x1001134, 0x100113a
+# CHECK: 0000000001001140 <pc24dbl>:
+# CHECK: bprp    5, 0x1001140, 0x1001146
+# CHECK: bprp    6, 0x1001146, 0x1001140
+
+# RUN: ld.lld %t.o --defsym foo16=pc16dbl+0xfffe --defsym bar16=pc16dbl+4-0x10000 --defsym foo32=pc32dbl+0xfffffffe --defsym bar32=pc32dbl+6-0x100000000 --defsym foo12=pc12dbl+0xffe --defsym bar12=pc12dbl+6-0x1000 --defsym foo24=pc24dbl+0xfffffe --defsym bar24=pc24dbl+6-0x1000000 -o %t.limits
+# RUN: llvm-objdump --no-show-raw-insn --mcpu=z13 -d %t.limits | FileCheck %s --check-prefix=LIMITS
+# LIMITS:      je   0x101111e
+# LIMITS-NEXT: jne  0xff1124
+# LIMITS:      jge  0x101001126
+# LIMITS-NEXT: jgne 0xffffffff0100112e
+# LIMITS:      bprp 5, 0x1002132, 0x1001134
+# LIMITS-NEXT: bprp 6, 0x100013a, 0x100113a
+# LIMITS:      bprp 5, 0x1001140, 0x200113e
+# LIMITS-NEXT: bprp 6, 0x1001146, 0x1146
+
+# RUN: not ld.lld %t.o --defsym foo16=pc16dbl+0x10000 --defsym bar16=pc16dbl+4-0x10002 --defsym foo32=pc32dbl+0x100000000 --defsym bar32=pc32dbl+6-0x100000002 --defsym foo12=pc12dbl+0x1000 --defsym bar12=pc12dbl+6-0x1002 --defsym foo24=pc24dbl+0x1000000 --defsym bar24=pc24dbl+6-0x1000002 -o /dev/null 2>&1 | FileCheck -DFILE=%t.o --check-prefix=ERROR-RANGE %s
+# ERROR-RANGE: error: [[FILE]]:(.text+0x2): relocation R_390_PC16DBL out of range: 65536 is not in [-65536, 65535]; references 'foo16'
+# ERROR-RANGE: error: [[FILE]]:(.text+0x6): relocation R_390_PC16DBL out of range: -65538 is not in [-65536, 65535]; references 'bar16'
+# ERROR-RANGE: error: [[FILE]]:(.text+0xa): relocation R_390_PC32DBL out of range: 4294967296 is not in [-4294967296, 4294967295]; references 'foo32'
+# ERROR-RANGE: error: [[FILE]]:(.text+0x10): relocation R_390_PC32DBL out of range: -4294967298 is not in [-4294967296, 4294967295]; references 'bar32'
+# ERROR-RANGE: error: [[FILE]]:(.text+0x15): relocation R_390_PC12DBL out of range: 4096 is not in [-4096, 4095]; references 'foo12'
+# ERROR-RANGE: error: [[FILE]]:(.text+0x1b): relocation R_390_PC12DBL out of range: -4098 is not in [-4096, 4095]; references 'bar12'
+# ERROR-RANGE: error: [[FILE]]:(.text+0x23): relocation R_390_PC24DBL out of range: 16777216 is not in [-16777216, 16777215]; references 'foo24'
+# ERROR-RANGE: error: [[FILE]]:(.text+0x29): relocation R_390_PC24DBL out of range: -16777218 is not in [-16777216, 16777215]; references 'bar24'
+
+# RUN: not ld.lld %t.o --defsym foo16=pc16dbl+1 --defsym bar16=pc16dbl-1 --defsym foo32=pc32dbl+1 --defsym bar32=pc32dbl-1 --defsym foo12=pc12dbl+1 --defsym bar12=pc12dbl-1 --defsym foo24=pc24dbl+1 --defsym bar24=pc24dbl-1 -o /dev/null 2>&1 | FileCheck -DFILE=%t.o --check-prefix=ERROR-ALIGN %s
+# ERROR-ALIGN:      error: [[FILE]]:(.text+0x2): improper alignment for relocation R_390_PC16DBL: 0x1 is not aligned to 2 bytes
+# ERROR-ALIGN-NEXT: error: [[FILE]]:(.text+0x6): improper alignment for relocation R_390_PC16DBL: 0xFFFFFFFFFFFFFFFB is not aligned to 2 bytes
+# ERROR-ALIGN-NEXT: error: [[FILE]]:(.text+0xa): improper alignment for relocation R_390_PC32DBL: 0x1 is not aligned to 2 bytes
+# ERROR-ALIGN-NEXT: error: [[FILE]]:(.text+0x10): improper alignment for relocation R_390_PC32DBL: 0xFFFFFFFFFFFFFFF9 is not aligned to 2 bytes
+# ERROR-ALIGN-NEXT: error: [[FILE]]:(.text+0x15): improper alignment for relocation R_390_PC12DBL: 0x1 is not aligned to 2 bytes
+# ERROR-ALIGN-NEXT: error: [[FILE]]:(.text+0x1b): improper alignment for relocation R_390_PC12DBL: 0xFFFFFFFFFFFFFFF9 is not aligned to 2 bytes
+# ERROR-ALIGN-NEXT: error: [[FILE]]:(.text+0x23): improper alignment for relocation R_390_PC24DBL: 0x1 is not aligned to 2 bytes
+# ERROR-ALIGN-NEXT: error: [[FILE]]:(.text+0x29): improper alignment for relocation R_390_PC24DBL: 0xFFFFFFFFFFFFFFF9 is not aligned to 2 bytes
+
+.global _start
+.global pc16dbl
+.global pc32dbl
+.global pc12dbl
+.global pc24dbl
+_start:
+pc16dbl:
+     je   foo16
+     jne  bar16
+pc32dbl:
+     jge  foo32
+     jgne bar32
+pc12dbl:
+     bprp 5,foo12,0
+     bprp 6,bar12,0
+pc24dbl:
+     bprp 5,0,foo24
+     bprp 6,0,bar24

diff  --git a/lld/test/ELF/systemz-tls-gd.s b/lld/test/ELF/systemz-tls-gd.s
new file mode 100644
index 00000000000000..3976f55a6ae39e
--- /dev/null
+++ b/lld/test/ELF/systemz-tls-gd.s
@@ -0,0 +1,142 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+# RUN: echo '.tbss; .globl b, c; b: .zero 4; c:' | llvm-mc -filetype=obj -triple=s390x-unknown-linux - -o %t1.o
+# RUN: ld.lld -shared -soname=t1.so %t1.o -o %t1.so
+
+# RUN: ld.lld -shared %t.o %t1.o -o %t.so
+# RUN: llvm-readelf -r %t.so | FileCheck --check-prefix=GD-REL %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t.so | FileCheck --check-prefix=GD %s
+# RUN: llvm-objdump --section .data.rel.ro --full-contents %t.so | FileCheck --check-prefix=GD-DATA %s
+
+# RUN: ld.lld %t.o %t1.o -o %t.le
+# RUN: llvm-readelf -r %t.le | FileCheck --check-prefix=NOREL %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t.le | FileCheck --check-prefix=LE %s
+# RUN: llvm-objdump --section .data.rel.ro --full-contents %t.le | FileCheck --check-prefix=LE-DATA %s
+
+# RUN: ld.lld %t.o %t1.so -o %t.ie
+# RUN: llvm-readelf -r %t.ie | FileCheck --check-prefix=IE-REL %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t.ie | FileCheck --check-prefix=IE %s
+# RUN: llvm-objdump --section .data.rel.ro --full-contents %t.ie | FileCheck --check-prefix=IE-DATA %s
+
+# GD-REL: Relocation section '.rela.dyn' at offset {{.*}} contains 6 entries:
+# GD-REL:      0000000000002570 0000000200000036 R_390_TLS_DTPMOD 0000000000000008 a + 0
+# GD-REL-NEXT: 0000000000002578 0000000200000037 R_390_TLS_DTPOFF 0000000000000008 a + 0
+# GD-REL-NEXT: 0000000000002580 0000000300000036 R_390_TLS_DTPMOD 000000000000000c b + 0
+# GD-REL-NEXT: 0000000000002588 0000000300000037 R_390_TLS_DTPOFF 000000000000000c b + 0
+# GD-REL-NEXT: 0000000000002590 0000000400000036 R_390_TLS_DTPMOD 0000000000000010 c + 0
+# GD-REL-NEXT: 0000000000002598 0000000400000037 R_390_TLS_DTPOFF 0000000000000010 c + 0
+
+## _GLOBAL_OFFSET_TABLE is at 0x2558
+# GD:      larl    %r12, 0x2558
+
+## GOT offset of the TLS module ID / offset pair for a is at 0x2460
+# GD-NEXT: lgrl    %r2, 0x2460
+# GD-NEXT: brasl   %r14, 0x1440
+# GD-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## GOT offset of the TLS module ID / offset pair for b is at 0x2468
+# GD-NEXT: lgrl    %r2, 0x2468
+# GD-NEXT: brasl   %r14, 0x1440
+# GD-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## GOT offset of the TLS module ID / offset pair for c is at 0x2470
+# GD-NEXT: lgrl    %r2, 0x2470
+# GD-NEXT: brasl   %r14, 0x1440
+# GD-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## Constant pool holding GOT offsets of TLS module ID / offset pairs:
+# a: 0x2570 / 0x18
+# b: 0x2580 / 0x28
+# c: 0x2590 / 0x38
+# GD-DATA:      2460 00000000 00000018 00000000 00000028
+# GD-DATA-NEXT: 2470 00000000 00000038
+
+# NOREL: no relocations
+
+## _GLOBAL_OFFSET_TABLE is at 0x1002230
+# LE:      larl    %r12, 0x1002230
+
+## TP offset of a is at 0x1002218
+# LE-NEXT: lgrl    %r2, 0x1002218
+# LE-NEXT: brcl    0,
+# LE-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## TP offset of b is at 0x1002220
+# LE-NEXT: lgrl    %r2, 0x1002220
+# LE-NEXT: brcl    0,
+# LE-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## TP offset of c is at 0x1002228
+# LE-NEXT: lgrl    %r2, 0x1002228
+# LE-NEXT: brcl    0,
+# LE-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## TP offsets
+# a: -8
+# b: -4
+# c: 0
+# LE-DATA:      1002218 ffffffff fffffff8 ffffffff fffffffc
+# LE-DATA-NEXT: 1002228 00000000 00000000
+
+
+# IE-REL: Relocation section '.rela.dyn' at offset {{.*}} contains 2 entries:
+# IE-REL:      0000000001002430 0000000200000038 R_390_TLS_TPOFF 0000000000000000 b + 0
+# IE-REL-NEXT: 0000000001002438 0000000300000038 R_390_TLS_TPOFF 0000000000000000 c + 0
+
+## _GLOBAL_OFFSET_TABLE is at 0x1002418
+# IE:      larl    %r12, 0x1002418
+
+## TP offset of a is at 0x1002340
+# IE-NEXT: lgrl    %r2, 0x1002340
+# IE-NEXT: brcl    0,
+# IE-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## GOT offset of the TP offset for b is at 0x1002348
+# IE-NEXT: lgrl    %r2, 0x1002348
+# IE-NEXT: lg      %r2, 0(%r2,%r12)
+# IE-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## GOT offset of the TP offset for c is at 0x1002350
+# IE-NEXT: lgrl    %r2, 0x1002350
+# IE-NEXT: lg      %r2, 0(%r2,%r12)
+# IE-NEXT: lgf     %r2, 0(%r2,%r7)
+
+## TP offsets (a) / GOT offset of TP offsets (b, c)
+# a: -4
+# b: 0x1002430 / 0x18
+# c: 0x1002438 / 0x20
+# IE-DATA:      1002340 ffffffff fffffffc 00000000 00000018
+# IE-DATA-NEXT: 1002350 00000000 00000020
+
+
+ear     %r7,%a0
+sllg    %r7,%r1,32
+ear     %r7,%a1
+larl    %r12,_GLOBAL_OFFSET_TABLE_
+
+lgrl    %r2,.LC0
+brasl   %r14,__tls_get_offset at PLT:tls_gdcall:a
+lgf     %r2,0(%r2,%r7)
+
+lgrl    %r2,.LC1
+brasl   %r14,__tls_get_offset at PLT:tls_gdcall:b
+lgf     %r2,0(%r2,%r7)
+
+lgrl    %r2,.LC2
+brasl   %r14,__tls_get_offset at PLT:tls_gdcall:c
+lgf     %r2,0(%r2,%r7)
+
+        .section        .data.rel.ro,"aw"
+        .align  8
+.LC0:
+        .quad   a at TLSGD
+.LC1:
+        .quad   b at TLSGD
+.LC2:
+        .quad   c at TLSGD
+
+	.section .tbss
+	.globl a
+	.zero 8
+a:
+	.zero 4

diff  --git a/lld/test/ELF/systemz-tls-ie.s b/lld/test/ELF/systemz-tls-ie.s
new file mode 100644
index 00000000000000..27b642ed2dfc5f
--- /dev/null
+++ b/lld/test/ELF/systemz-tls-ie.s
@@ -0,0 +1,87 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+
+# RUN: ld.lld -shared %t.o -o %t.so
+# RUN: llvm-readelf -r %t.so | FileCheck --check-prefix=IE-REL %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t.so | FileCheck --check-prefix=IE %s
+# RUN: llvm-objdump --section .data --full-contents %t.so | FileCheck --check-prefix=IE-DATA %s
+
+# RUN: ld.lld %t.o -o %t
+# RUN: llvm-readelf -r %t | FileCheck --check-prefix=NOREL %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t | FileCheck --check-prefix=LE %s
+# RUN: llvm-objdump --section .data --full-contents %t | FileCheck --check-prefix=LE-DATA %s
+# RUN: llvm-objdump --section .got --full-contents %t | FileCheck --check-prefix=LE-GOT %s
+
+# IE-REL: Relocation section '.rela.dyn' at offset {{.*}} contains 4 entries:
+# IE-REL: 0000000000003478 000000000000000c R_390_RELATIVE 2460
+# IE-REL: 0000000000002460 0000000100000038 R_390_TLS_TPOFF 0000000000000008 a + 0
+# IE-REL: 0000000000002468 0000000200000038 R_390_TLS_TPOFF 000000000000000c b + 0
+# IE-REL: 0000000000002470 0000000300000038 R_390_TLS_TPOFF 0000000000000010 c + 0
+
+## TP offset for a is at 0x2460
+# IE:      lgrl    %r1, 0x2460
+# IE-NEXT: lgf     %r1, 0(%r1,%r7)
+
+## TP offset for b is at 0x2468
+# IE-NEXT: lgrl    %r1, 0x2468
+# IE-NEXT: lgf     %r1, 0(%r1,%r7)
+
+## TP offset for c is at 0x2470
+# IE-NEXT: lgrl    %r1, 0x2470
+# IE-NEXT: lgf     %r1, 0(%r1,%r7)
+
+## Data element: TP offset for a is at 0x2460 (relocated via R_390_RELATIVE above)
+# IE-DATA: 3478 00000000 00000000
+
+# NOREL: no relocations
+
+## TP offset for a is at 0x1002250
+# LE:      lgrl    %r1, 0x1002250
+# LE-NEXT: lgf     %r1, 0(%r1,%r7)
+
+## TP offset for b is at 0x1002258
+# LE-NEXT: lgrl    %r1, 0x1002258
+# LE-NEXT: lgf     %r1, 0(%r1,%r7)
+
+## TP offset for c is at 0x1002260
+# LE-NEXT: lgrl    %r1, 0x1002260
+# LE-NEXT: lgf     %r1, 0(%r1,%r7)
+
+## Data element: TP offset for a is at 0x1002250
+# LE-DATA: 00000000 01002250
+
+## TP offsets in GOT:
+# a: -8
+# b: -4
+# c: 0
+# LE-GOT: 1002238 00000000 00000000 00000000 00000000
+# LE-GOT: 1002248 00000000 00000000 ffffffff fffffff8
+# LE-GOT: 1002258 ffffffff fffffffc 00000000 00000000
+
+ear     %r7,%a0
+sllg    %r7,%r1,32
+ear     %r7,%a1
+
+lgrl    %r1, a at indntpoff
+lgf     %r1,0(%r1,%r7)
+
+lgrl    %r1, b at indntpoff
+lgf     %r1,0(%r1,%r7)
+
+lgrl    %r1, c at indntpoff
+lgf     %r1,0(%r1,%r7)
+
+	.data
+	.reloc .,R_390_TLS_IE64,a
+	.space 8
+
+	.section .tbss
+	.globl a
+	.globl b
+	.globl c
+	.zero 8
+a:
+	.zero 4
+b:
+	.zero 4
+c:

diff  --git a/lld/test/ELF/systemz-tls-ld.s b/lld/test/ELF/systemz-tls-ld.s
new file mode 100644
index 00000000000000..2cb36d7294f2b0
--- /dev/null
+++ b/lld/test/ELF/systemz-tls-ld.s
@@ -0,0 +1,114 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+
+# RUN: ld.lld -shared %t.o -o %t.so
+# RUN: llvm-readelf -r %t.so | FileCheck --check-prefix=LD-REL %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t.so | FileCheck --check-prefix=LD %s
+# RUN: llvm-objdump --section .data.rel.ro --full-contents %t.so | FileCheck --check-prefix=LD-DATA %s
+
+# RUN: ld.lld %t.o -o %t
+# RUN: llvm-readelf -r %t | FileCheck --check-prefix=NOREL %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t | FileCheck --check-prefix=LE %s
+# RUN: llvm-objdump --section .data.rel.ro --full-contents %t | FileCheck --check-prefix=LE-DATA %s
+
+# LD-REL: Relocation section '.rela.dyn' at offset {{.*}} contains 1 entries:
+# LD-REL: 00000000000024f8 0000000000000036 R_390_TLS_DTPMOD 0
+
+## _GLOBAL_OFFSET_TABLE is at 0x24e0
+# LD:      larl    %r12, 0x24e0
+
+## GOT offset of the LDM TLS module ID is at 0x23e0
+# LD-NEXT: lgrl    %r2, 0x23e0
+# LD-NEXT: brasl   %r14, 0x13c0
+# LD-NEXT: la      %r2, 0(%r2,%r7)
+
+## DTP offset for a is at 0x23e8
+# LD-NEXT: lgrl    %r1, 0x23e8
+# LD-NEXT: lgf     %r1, 0(%r1,%r2)
+
+## DTP offset for b is at 0x23f0
+# LD-NEXT: lgrl    %r1, 0x23f0
+# LD-NEXT: lgf     %r1, 0(%r1,%r2)
+
+## DTP offset for c is at 0x23f8
+# LD-NEXT: lgrl    %r1, 0x23f8
+# LD-NEXT: lgf     %r1, 0(%r1,%r2)
+
+## Constant pool holding GOT offsets of TLS module ID and DTP offsets:
+# TLS module ID: 0x24f8 / 0x18
+# a: 8
+# b: 12
+# c: 16
+# LD-DATA: 23e0 00000000 00000018 00000000 00000008
+# LD-DATA: 23f0 00000000 0000000c 00000000 00000010
+
+# NOREL: no relocations
+
+## _GLOBAL_OFFSET_TABLE is at 0x1002230
+# LE:      larl    %r12, 0x1002230
+
+## GOT offset of the LDM TLS module ID is at 0x1002210
+# LE-NEXT: lgrl    %r2, 0x1002210
+# LE-NEXT: brcl    0,
+# LE-NEXT: la      %r2, 0(%r2,%r7)
+
+## TP offset for a is at 0x1002218
+# LE-NEXT: lgrl    %r1, 0x1002218
+# LE-NEXT: lgf     %r1, 0(%r1,%r2)
+
+## TP offset for b is at 0x1002220
+# LE-NEXT: lgrl    %r1, 0x1002220
+# LE-NEXT: lgf     %r1, 0(%r1,%r2)
+
+## TP offset for c is at 0x1002228
+# LE-NEXT: lgrl    %r1, 0x1002228
+# LE-NEXT: lgf     %r1, 0(%r1,%r2)
+
+## zeroed LDM / TP offsets:
+# LDM TLS: 0
+# a: -8
+# b: -4
+# c: 0
+# LE-DATA: 1002210 00000000 00000000 ffffffff fffffff8
+# LE-DATA: 1002220 ffffffff fffffffc 00000000 00000000
+
+
+ear     %r7,%a0
+sllg    %r7,%r1,32
+ear     %r7,%a1
+larl    %r12,_GLOBAL_OFFSET_TABLE_
+
+lgrl    %r2,.LC0
+brasl   %r14,__tls_get_offset at PLT:tls_ldcall:a
+la      %r2,0(%r2,%r7)
+
+lgrl    %r1, .LC1
+lgf     %r1,0(%r1,%r2)
+
+lgrl    %r1, .LC2
+lgf     %r1,0(%r1,%r2)
+
+lgrl    %r1, .LC3
+lgf     %r1,0(%r1,%r2)
+
+        .section        .data.rel.ro,"aw"
+        .align  8
+.LC0:
+        .quad   a at TLSLDM
+.LC1:
+        .quad   a at DTPOFF
+.LC2:
+        .quad   b at DTPOFF
+.LC3:
+        .quad   c at DTPOFF
+
+	.section .tbss
+	.globl a
+	.globl b
+	.globl c
+	.zero 8
+a:
+	.zero 4
+b:
+	.zero 4
+c:

diff  --git a/lld/test/ELF/systemz-tls-le.s b/lld/test/ELF/systemz-tls-le.s
new file mode 100644
index 00000000000000..9e41fc768da391
--- /dev/null
+++ b/lld/test/ELF/systemz-tls-le.s
@@ -0,0 +1,61 @@
+# REQUIRES: systemz
+# RUN: llvm-mc -filetype=obj -triple=s390x-unknown-linux %s -o %t.o
+
+# RUN: ld.lld %t.o -o %t
+# RUN: llvm-readelf -r %t | FileCheck --check-prefix=NOREL %s
+# RUN: llvm-objdump -d --no-show-raw-insn %t | FileCheck --check-prefix=LE %s
+# RUN: llvm-objdump --section .data.rel.ro --full-contents %t | FileCheck --check-prefix=LE-DATA %s
+
+# NOREL: no relocations
+
+## TP offset for a is at 0x1002200
+# LE:      lgrl    %r1, 0x1002200
+# LE-NEXT: lgf     %r1, 0(%r1,%r7)
+
+## TP offset for b is at 0x1002208
+# LE-NEXT: lgrl    %r1, 0x1002208
+# LE-NEXT: lgf     %r1, 0(%r1,%r7)
+
+## TP offset for c is at 0x1002210
+# LE-NEXT: lgrl    %r1, 0x1002210
+# LE-NEXT: lgf     %r1, 0(%r1,%r7)
+
+## TP offsets:
+# a: -8
+# b: -4
+# c: 0
+# LE-DATA: 1002200 ffffffff fffffff8 ffffffff fffffffc
+# LE-DATA: 1002210 00000000 00000000
+
+ear     %r7,%a0
+sllg    %r7,%r1,32
+ear     %r7,%a1
+
+lgrl    %r1, .LC0
+lgf     %r1,0(%r1,%r7)
+
+lgrl    %r1, .LC1
+lgf     %r1,0(%r1,%r7)
+
+lgrl    %r1, .LC2
+lgf     %r1,0(%r1,%r7)
+
+        .section        .data.rel.ro,"aw"
+        .align  8
+.LC0:
+        .quad   a at ntpoff
+.LC1:
+        .quad   b at ntpoff
+.LC2:
+        .quad   c at ntpoff
+
+	.section .tbss
+	.globl a
+	.globl b
+	.globl c
+	.zero 8
+a:
+	.zero 4
+b:
+	.zero 4
+c:

diff  --git a/lld/test/lit.cfg.py b/lld/test/lit.cfg.py
index b3e07f1f823cc4..d309c2ad4ee284 100644
--- a/lld/test/lit.cfg.py
+++ b/lld/test/lit.cfg.py
@@ -83,6 +83,7 @@
                 "PowerPC": "ppc",
                 "RISCV": "riscv",
                 "Sparc": "sparc",
+                "SystemZ": "systemz",
                 "WebAssembly": "wasm",
                 "X86": "x86",
             },


        


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