Doxygenize the documentation comments

src/IceRegistersARM32.h

Index: src/IceRegistersARM32.h
diff --git a/src/IceRegistersARM32.h b/src/IceRegistersARM32.h
index 2ad1c8b36adef2dfb57836cd13efb255f2b47347..39efd7f0f84f630e6767bab70bc0a2374275b2a5 100644
--- a/src/IceRegistersARM32.h
+++ b/src/IceRegistersARM32.h
@@ -6,9 +6,10 @@
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
-//
-// This file declares the registers and their encodings for ARM32.
-//
+///
+/// \file
+/// This file declares the registers and their encodings for ARM32.
+///
 //===----------------------------------------------------------------------===//
 
 #ifndef SUBZERO_SRC_ICEREGISTERSARM32_H
@@ -22,8 +23,8 @@ namespace Ice {
 
 namespace RegARM32 {
 
-// An enum of every register. The enum value may not match the encoding
-// used to binary encode register operands in instructions.
+/// An enum of every register. The enum value may not match the encoding
+/// used to binary encode register operands in instructions.
 enum AllRegisters {
 #define X(val, encode, name, scratch, preserved, stackptr, frameptr, isInt,    \
           isFP)                                                                \
@@ -36,8 +37,8 @@ enum AllRegisters {
 #undef X
 };
 
-// An enum of GPR Registers. The enum value does match the encoding used
-// to binary encode register operands in instructions.
+/// An enum of GPR Registers. The enum value does match the encoding used
+/// to binary encode register operands in instructions.
 enum GPRRegister {
 #define X(val, encode, name, scratch, preserved, stackptr, frameptr, isInt,    \
           isFP)                                                                \