Index: llvm/lib/BinaryFormat/XCOFF.cpp
===================================================================
--- llvm/lib/BinaryFormat/XCOFF.cpp
+++ llvm/lib/BinaryFormat/XCOFF.cpp
@@ -22,6 +22,8 @@
     return "TC0";
   case XCOFF::XMC_BS:
     return "BS";
+  case XCOFF::XMC_RO:
+    return "RO";
   default:
     report_fatal_error("Unhandled storage-mapping class.");
   }
Index: llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
===================================================================
--- llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -1861,6 +1861,10 @@
   if (Kind.isBSS())
     return DataSection;
 
+  if (Kind.isReadOnly() && !Kind.isMergeableConst() &&
+      !Kind.isMergeableCString())
+    return ReadOnlySection;
+
   report_fatal_error("XCOFF other section types not yet implemented.");
 }
 
Index: llvm/lib/MC/MCObjectFileInfo.cpp
===================================================================
--- llvm/lib/MC/MCObjectFileInfo.cpp
+++ llvm/lib/MC/MCObjectFileInfo.cpp
@@ -777,6 +777,10 @@
   DataSection = Ctx->getXCOFFSection(
       ".data", XCOFF::StorageMappingClass::XMC_RW, XCOFF::XTY_SD,
       XCOFF::C_HIDEXT, SectionKind::getData());
+
+  ReadOnlySection = Ctx->getXCOFFSection(
+      ".rodata", XCOFF::StorageMappingClass::XMC_RO, XCOFF::XTY_SD,
+      XCOFF::C_HIDEXT, SectionKind::getReadOnly());
 }
 
 void MCObjectFileInfo::InitMCObjectFileInfo(const Triple &TheTriple, bool PIC,
Index: llvm/lib/MC/MCSectionXCOFF.cpp
===================================================================
--- llvm/lib/MC/MCSectionXCOFF.cpp
+++ llvm/lib/MC/MCSectionXCOFF.cpp
@@ -27,6 +27,13 @@
     return;
   }
 
+  if (getKind().isReadOnly()) {
+    if (getMappingClass() != XCOFF::XMC_RO)
+      report_fatal_error("Unhandled storage-mapping class for .rodata csect.");
+    OS << "\t.csect " << QualName->getName() << '\n';
+    return;
+  }
+
   if (getKind().isData()) {
     switch (getMappingClass()) {
     case XCOFF::XMC_RW:
Index: llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
===================================================================
--- llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
+++ llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
@@ -1747,7 +1747,9 @@
     report_fatal_error("COMDAT not yet supported by AIX.");
 
   SectionKind GVKind = getObjFileLowering().getKindForGlobal(GV, TM);
-  if (!GVKind.isCommon() && !GVKind.isBSS() && !GVKind.isData())
+  if ((!GVKind.isCommon() && !GVKind.isBSS() && !GVKind.isData() &&
+       !GVKind.isReadOnly()) ||
+      GVKind.isMergeableCString() || GVKind.isMergeableConst())
     report_fatal_error("Encountered a global variable kind that is "
                        "not supported yet.");
 
Index: llvm/test/CodeGen/PowerPC/aix-xcoff-rodata.ll
===================================================================
--- /dev/null
+++ llvm/test/CodeGen/PowerPC/aix-xcoff-rodata.ll
@@ -0,0 +1,50 @@
+; RUN: llc -verify-machineinstrs -mcpu=pwr7 -mtriple powerpc-ibm-aix-xcoff  < %s | FileCheck %s
+; RUN: llc -verify-machineinstrs -mcpu=pwr7 -mtriple powerpc64-ibm-aix-xcoff < %s | FileCheck %s
+
+@const_ivar = constant i32 35, align 4
+@const_llvar = constant i64 36, align 8
+@const_svar = constant i16 37, align 2
+@const_fvar = constant float 8.000000e+02, align 4
+@const_dvar = constant double 9.000000e+02, align 8
+@const_over_aligned = constant double 9.000000e+02, align 32
+@const_chrarray = constant [4 x i8] c"abcd", align 1
+@const_dblarr = constant [4 x double] [double 1.000000e+00, double 2.000000e+00, double 3.000000e+00, double 4.000000e+00], align 8
+
+; CHECK:               .csect .rodata[RO]
+; CHECK-NEXT:          .globl  const_ivar
+; CHECK-NEXT:          .align  2
+; CHECK-NEXT:  const_ivar:
+; CHECK-NEXT:          .long   35
+; CHECK-NEXT:          .globl  const_llvar
+; CHECK-NEXT:          .align  3
+; CHECK-NEXT:  const_llvar:
+; CHECK-NEXT:          .llong  36
+; CHECK-NEXT:          .globl  const_svar
+; CHECK-NEXT:          .align  1
+; CHECK-NEXT:  const_svar:
+; CHECK-NEXT:          .short  37
+; CHECK-NEXT:          .globl  const_fvar
+; CHECK-NEXT:          .align  2
+; CHECK-NEXT:  const_fvar:
+; CHECK-NEXT:          .long   1145569280
+; CHECK-NEXT:          .globl  const_dvar
+; CHECK-NEXT:          .align  3
+; CHECK-NEXT:  const_dvar:
+; CHECK-NEXT:          .llong  4651127699538968576
+; CHECK-NEXT:          .globl  const_over_aligned
+; CHECK-NEXT:          .align  5
+; CHECK-NEXT:  const_over_aligned:
+; CHECK-NEXT:          .llong  4651127699538968576
+; CHECK-NEXT:          .globl  const_chrarray
+; CHECK-NEXT:  const_chrarray:
+; CHECK-NEXT:          .byte   97
+; CHECK-NEXT:          .byte   98
+; CHECK-NEXT:          .byte   99
+; CHECK-NEXT:          .byte   100
+; CHECK-NEXT:          .globl  const_dblarr
+; CHECK-NEXT:          .align  3
+; CHECK-NEXT:  const_dblarr:
+; CHECK-NEXT:          .llong  4607182418800017408
+; CHECK-NEXT:          .llong  4611686018427387904
+; CHECK-NEXT:          .llong  4613937818241073152
+; CHECK-NEXT:          .llong  4616189618054758400