* config/i386/i386.md (any_shiftrt): New code iterator.

[pf3gnuchains/gcc-fork.git] / gcc / config / i386 / sync.md

diff --git a/gcc/config/i386/sync.md b/gcc/config/i386/sync.md
index 0df85c7..feea161 100644 (file)
--- a/gcc/config/i386/sync.md
+++ b/gcc/config/i386/sync.md
@@ -202,6 +202,9 @@
        return "lock{%;| }dec{<imodesuffix>}\t%0";
     }
 
+  if (x86_maybe_negate_const_int (&operands[1], <MODE>mode))
+    return "lock{%;| }sub{<imodesuffix>}\t{%1, %0|%0, %1}";
+
   return "lock{%;| }add{<imodesuffix>}\t{%1, %0|%0, %1}";
 })