Give sentinel traits the right to determine the policy where the sentinel is kept.

This should result in less indirect memory accesses, less dead writes and tighter code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66061 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 0 deletions

diff --git a/include/llvm/Function.h b/include/llvm/Function.h
index 37e8f19f62..cb3cc939d0 100644
--- a/include/llvm/Function.h
+++ b/include/llvm/Function.h
@@ -38,6 +38,10 @@ template<> struct ilist_traits<BasicBlock>
     return static_cast<BasicBlock*>(&Sentinel);
   }
   static void destroySentinel(BasicBlock*) {}
+
+  BasicBlock *provideInitialHead() const { return createSentinel(); }
+  BasicBlock *ensureHead(BasicBlock*) const { return createSentinel(); }
+
   static iplist<BasicBlock> &getList(Function *F);
   static ValueSymbolTable *getSymTab(Function *ItemParent);
   static int getListOffset();
@@ -52,6 +56,10 @@ template<> struct ilist_traits<Argument>
     return static_cast<Argument*>(&Sentinel);
   }
   static void destroySentinel(Argument*) {}
+
+  Argument *provideInitialHead() const { return createSentinel(); }
+  Argument *ensureHead(Argument*) const { return createSentinel(); }
+
   static iplist<Argument> &getList(Function *F);
   static ValueSymbolTable *getSymTab(Function *ItemParent);
   static int getListOffset();