Support alignment specifier for NEON vld/vst instructions

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86404 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMAddressingModes.h b/lib/Target/ARM/ARMAddressingModes.h
index c603708..6ee1b68 100644
--- a/lib/Target/ARM/ARMAddressingModes.h
+++ b/lib/Target/ARM/ARMAddressingModes.h
@@ -541,13 +541,15 @@
   //
   // This is used for NEON load / store instructions.
   //
-  // addrmode6 := reg with optional writeback
+  // addrmode6 := reg with optional writeback and alignment
   //
-  // This is stored in three operands [regaddr, regupdate, opc].  The first is
-  // the address register.  The second register holds the value of a post-access
-  // increment for writeback or reg0 if no writeback or if the writeback
-  // increment is the size of the memory access.  The third operand encodes
-  // whether there is writeback to the address register.
+  // This is stored in four operands [regaddr, regupdate, opc, align].  The
+  // first is the address register.  The second register holds the value of
+  // a post-access increment for writeback or reg0 if no writeback or if the
+  // writeback increment is the size of the memory access.  The third
+  // operand encodes whether there is writeback to the address register. The
+  // fourth operand is the value of the alignment specifier to use or zero if
+  // no explicit alignment.
 
   static inline unsigned getAM6Opc(bool WB = false) {
     return (int)WB;