Index: include/llvm/BinaryFormat/ELFRelocs/PowerPC64.def
===================================================================
--- include/llvm/BinaryFormat/ELFRelocs/PowerPC64.def
+++ include/llvm/BinaryFormat/ELFRelocs/PowerPC64.def
@@ -35,6 +35,7 @@
 #undef R_PPC64_ADDR16_HIGHERA
 #undef R_PPC64_ADDR16_HIGHEST
 #undef R_PPC64_ADDR16_HIGHESTA
+#undef R_PPC64_UADDR64
 #undef R_PPC64_REL64
 #undef R_PPC64_TOC16
 #undef R_PPC64_TOC16_LO
@@ -128,6 +129,7 @@
 ELF_RELOC(R_PPC64_ADDR16_HIGHERA,       40)
 ELF_RELOC(R_PPC64_ADDR16_HIGHEST,       41)
 ELF_RELOC(R_PPC64_ADDR16_HIGHESTA,      42)
+ELF_RELOC(R_PPC64_UADDR64,              43)
 ELF_RELOC(R_PPC64_REL64,                44)
 ELF_RELOC(R_PPC64_TOC16,                47)
 ELF_RELOC(R_PPC64_TOC16_LO,             48)
Index: lib/MC/ELFObjectWriter.cpp
===================================================================
--- lib/MC/ELFObjectWriter.cpp
+++ lib/MC/ELFObjectWriter.cpp
@@ -922,6 +922,7 @@
 void ELFWriter::writeRelocations(const MCAssembler &Asm,
                                        const MCSectionELF &Sec) {
   std::vector<ELFRelocationEntry> &Relocs = OWriter.Relocations[&Sec];
+  unsigned EMachine = OWriter.TargetObjectWriter->getEMachine();
 
   // We record relocations by pushing to the end of a vector. Reverse the vector
   // to get the relocations in the order they were created.
@@ -938,7 +939,7 @@
 
     if (is64Bit()) {
       write(Entry.Offset);
-      if (OWriter.TargetObjectWriter->getEMachine() == ELF::EM_MIPS) {
+      if (EMachine == ELF::EM_MIPS) {
         write(uint32_t(Index));
 
         write(OWriter.TargetObjectWriter->getRSsym(Entry.Type));
@@ -947,7 +948,11 @@
         write(OWriter.TargetObjectWriter->getRType(Entry.Type));
       } else {
         struct ELF::Elf64_Rela ERE64;
-        ERE64.setSymbolAndType(Index, Entry.Type);
+        unsigned Type = Entry.Type;
+        if (EMachine == ELF::EM_PPC64 && Type == ELF::R_PPC64_ADDR64 &&
+            Entry.Offset % 8 != 0)
+          Type = ELF::R_PPC64_UADDR64;
+        ERE64.setSymbolAndType(Index, Type);
         write(ERE64.r_info);
       }
       if (hasRelocationAddend())
@@ -956,13 +961,17 @@
       write(uint32_t(Entry.Offset));
 
       struct ELF::Elf32_Rela ERE32;
-      ERE32.setSymbolAndType(Index, Entry.Type);
+      unsigned Type = Entry.Type;
+      if (EMachine == ELF::EM_PPC && Type == ELF::R_PPC_ADDR32 &&
+          Entry.Offset % 4 != 0)
+        Type = ELF::R_PPC_UADDR32;
+      ERE32.setSymbolAndType(Index, Type);
       write(ERE32.r_info);
 
       if (hasRelocationAddend())
         write(uint32_t(Entry.Addend));
 
-      if (OWriter.TargetObjectWriter->getEMachine() == ELF::EM_MIPS) {
+      if (EMachine == ELF::EM_MIPS) {
         if (uint32_t RType =
                 OWriter.TargetObjectWriter->getRType2(Entry.Type)) {
           write(uint32_t(Entry.Offset));
Index: lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
===================================================================
--- lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
+++ lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
@@ -400,6 +400,7 @@
         Type = ELF::R_PPC64_TOC;
         break;
       case MCSymbolRefExpr::VK_None:
+        // R_PPC64_UADDR64 may be emitted if r_offset % 8 != 0.
         Type = ELF::R_PPC64_ADDR64;
         break;
       case MCSymbolRefExpr::VK_PPC_DTPMOD:
@@ -414,6 +415,7 @@
       }
       break;
     case FK_Data_4:
+      // R_PPC_UADDR32 may be emitted if r_offset % 4 != 0.
       Type = ELF::R_PPC_ADDR32;
       break;
     case FK_Data_2:
Index: test/MC/PowerPC/ppc32-uaddr.s
===================================================================
--- /dev/null
+++ test/MC/PowerPC/ppc32-uaddr.s
@@ -0,0 +1,9 @@
+# RUN: llvm-mc -filetype=obj -triple=powerpc %s | llvm-readobj -r | FileCheck %s
+
+# CHECK:      0x1 R_PPC_UADDR32 foo 0x0
+# CHECK-NEXT: 0x5 R_PPC_UADDR32 foo 0x1
+
+.data
+.byte 0
+.long foo
+.long foo+1
Index: test/MC/PowerPC/ppc64-uaddr.s
===================================================================
--- /dev/null
+++ test/MC/PowerPC/ppc64-uaddr.s
@@ -0,0 +1,10 @@
+# RUN: llvm-mc -filetype=obj -triple=powerpc64 %s | llvm-readobj -r | FileCheck %s
+# RUN: llvm-mc -filetype=obj -triple=powerpc64le %s | llvm-readobj -r | FileCheck %s
+
+# CHECK:      0x1 R_PPC64_UADDR64 foo 0x0
+# CHECK-NEXT: 0x9 R_PPC64_UADDR64 foo 0x1
+
+.data
+.byte 0
+.quad foo
+.quad foo+1