Add empty() methods for register def lists.

llvm-svn: 61890

1 files changed, 8 insertions, 0 deletions

diff --git a/llvm/include/llvm/CodeGen/MachineRegisterInfo.h b/llvm/include/llvm/CodeGen/MachineRegisterInfo.h
index f477e86554e..b313fce182f 100644
--- a/llvm/include/llvm/CodeGen/MachineRegisterInfo.h
+++ b/llvm/include/llvm/CodeGen/MachineRegisterInfo.h
@@ -81,6 +81,10 @@ public:
   }
   static reg_iterator reg_end() { return reg_iterator(0); }
 
+  /// reg_empty - Return true if there are no instructions using or defining the
+  /// specified register (it may be live-in).
+  bool reg_empty(unsigned RegNo) const { return reg_begin(RegNo) == reg_end(); }
+
   /// def_iterator/def_begin/def_end - Walk all defs of the specified register.
   typedef defusechain_iterator<false,true> def_iterator;
   def_iterator def_begin(unsigned RegNo) const {
@@ -88,6 +92,10 @@ public:
   }
   static def_iterator def_end() { return def_iterator(0); }
 
+  /// def_empty - Return true if there are no instructions defining the
+  /// specified register (it may be live-in).
+  bool def_empty(unsigned RegNo) const { return def_begin(RegNo) == def_end(); }
+
   /// use_iterator/use_begin/use_end - Walk all uses of the specified register.
   typedef defusechain_iterator<true,false> use_iterator;
   use_iterator use_begin(unsigned RegNo) const {