// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
+//
+// This file defines a MachineFunction pass which runs after register
+// allocation that turns subreg insert/extract instructions into register
+// copies, as needed. This ensures correct codegen even if the coalescer
+// isn't able to remove all subreg instructions.
+//
+//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "lowersubregs"
#include "llvm/CodeGen/Passes.h"