Speculatively micro-optimize memory-zeroing calls on Darwin 10.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49048 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86Subtarget.h b/lib/Target/X86/X86Subtarget.h
index 6488d47..c91088d 100644
--- a/lib/Target/X86/X86Subtarget.h
+++ b/lib/Target/X86/X86Subtarget.h
@@ -171,6 +171,12 @@
   bool GVRequiresExtraLoad(const GlobalValue* GV, const TargetMachine& TM,
                            bool isDirectCall) const;
 
+  /// This function returns the name of a function which has an interface
+  /// like the non-standard bzero function, if such a function exists on
+  /// the current subtarget and it is considered prefereable over
+  /// memset with zero passed as the second argument. Otherwise it
+  /// returns null.
+  const char *getBZeroEntry() const;
 };
 
 namespace X86 {