diff --git a/lib/Target/X86/README-SSE.txt b/lib/Target/X86/README-SSE.txt
index 2685956dc1a..b80661a5b79 100644
--- a/lib/Target/X86/README-SSE.txt
+++ b/lib/Target/X86/README-SSE.txt
@@ -18,6 +18,11 @@ Think about doing i64 math in SSE regs.
 
 //===---------------------------------------------------------------------===//
 
+Bitcast to<->from SSE registers should use movd/movq instead of going through
+the stack.  Testcase here: CodeGen/X86/bitcast.ll
+
+//===---------------------------------------------------------------------===//
+
 This testcase should have no SSE instructions in it, and only one load from
 a constant pool: