Index: llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
===================================================================
--- llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
+++ llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
@@ -1547,9 +1547,10 @@
 void PPCAIXAsmPrinter::SetupMachineFunction(MachineFunction &MF) {
   // Get the function descriptor symbol.
   CurrentFnDescSym = getSymbol(&MF.getFunction());
-  // Set the containing csect.
+  // Set the alignment and the containing csect.
   MCSectionXCOFF *FnDescSec = cast<MCSectionXCOFF>(
       getObjFileLowering().getSectionForFunctionDescriptor(CurrentFnDescSym));
+  FnDescSec->setAlignment(Align(Subtarget->isPPC64() ? 8 : 4));
   cast<MCSymbolXCOFF>(CurrentFnDescSym)->setContainingCsect(FnDescSec);
 
   return AsmPrinter::SetupMachineFunction(MF);
Index: llvm/test/CodeGen/PowerPC/aix-func-dsc-gen.ll
===================================================================
--- llvm/test/CodeGen/PowerPC/aix-func-dsc-gen.ll
+++ llvm/test/CodeGen/PowerPC/aix-func-dsc-gen.ll
@@ -63,7 +63,7 @@
 ; CHECK-NEXT:       SectionLen: 12
 ; CHECK-NEXT:       ParameterHashIndex: 0x0
 ; CHECK-NEXT:       TypeChkSectNum: 0x0
-; CHECK-NEXT:       SymbolAlignmentLog2: 0
+; CHECK-NEXT:       SymbolAlignmentLog2: 2
 ; CHECK-NEXT:       SymbolType: XTY_SD (0x1)
 ; CHECK-NEXT:       StorageMappingClass: XMC_DS (0xA)
 ; CHECK-NEXT:       StabInfoIndex: 0x0
Index: llvm/test/CodeGen/PowerPC/aix-xcoff-reloc.ll
===================================================================
--- llvm/test/CodeGen/PowerPC/aix-xcoff-reloc.ll
+++ llvm/test/CodeGen/PowerPC/aix-xcoff-reloc.ll
@@ -318,7 +318,7 @@
 ; SYM-NEXT:       SectionLen: 12
 ; SYM-NEXT:       ParameterHashIndex: 0x0
 ; SYM-NEXT:       TypeChkSectNum: 0x0
-; SYM-NEXT:       SymbolAlignmentLog2: 0
+; SYM-NEXT:       SymbolAlignmentLog2: 2
 ; SYM-NEXT:       SymbolType: XTY_SD (0x1)
 ; SYM-NEXT:       StorageMappingClass: XMC_DS (0xA)
 ; SYM-NEXT:       StabInfoIndex: 0x0