Don't return a std::vector in the Spiller interface, but take a reference to a

vector instead. This avoids needless copying and allocation.

Add documentation.

llvm-svn: 106788

1 files changed, 13 insertions, 5 deletions

diff --git a/llvm/lib/CodeGen/Spiller.h b/llvm/lib/CodeGen/Spiller.h
index dda52e871fe..02decad41ab 100644
--- a/llvm/lib/CodeGen/Spiller.h
+++ b/llvm/lib/CodeGen/Spiller.h
@@ -33,11 +33,19 @@ namespace llvm {
   public:
     virtual ~Spiller() = 0;
 
-    /// Spill the given live range. The method used will depend on the Spiller
-    /// implementation selected.
-    virtual std::vector<LiveInterval*> spill(LiveInterval *li,
-					     SmallVectorImpl<LiveInterval*> &spillIs,
-                                             SlotIndex *earliestIndex = 0) = 0;
+    /// spill - Spill the given live interval. The method used will depend on
+    /// the Spiller implementation selected.
+    ///
+    /// @param li            The live interval to be spilled.
+    /// @param spillIs       An essential hook into the register allocator guts
+    ///                      that perhaps serves a purpose(?!)
+    /// @param newIntervals  The newly created intervals will be appended here.
+    /// @param earliestIndex The earliest point for splitting. (OK, it's another
+    ///                      pointer to the allocator guts).
+    virtual void spill(LiveInterval *li,
+                       std::vector<LiveInterval*> &newIntervals,
+                       SmallVectorImpl<LiveInterval*> &spillIs,
+                       SlotIndex *earliestIndex = 0) = 0;
 
   };