Add support for rematerialization to InlineSpiller.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107351 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/Spiller.h b/lib/CodeGen/Spiller.h
index 02decad..450447b 100644
--- a/lib/CodeGen/Spiller.h
+++ b/lib/CodeGen/Spiller.h
@@ -37,8 +37,8 @@
     /// 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 spillIs       A list of intervals that are about to be spilled,
+    ///                      and so cannot be used for remat etc.
     /// @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).