diff --git a/gcc/match.pd b/gcc/match.pd
index 1d407414bee278c64c00d425d9f025c1c58d853d..b225d36dc758f1581502c8d03761544bfd499c01 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -7245,6 +7245,23 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
       && ANY_INTEGRAL_TYPE_P (type) && ANY_INTEGRAL_TYPE_P (TREE_TYPE(@0)))
   (IFN_REDUC_PLUS_WIDEN @0)))
 
+/* Canonicalize BIT_FIELD_REFS and shifts to BIT_FIELD_REFS.  */
+(for shift (rshift)
+     op (plus)
+ (simplify
+  (shift (BIT_FIELD_REF @0 @1 @2) integer_pow2p@3)
+  (if (INTEGRAL_TYPE_P (type))
+   (with { /* Can't use wide-int here as the precision differs between
+	      @1 and @3.  */
+	   unsigned HOST_WIDE_INT size = tree_to_uhwi (@1);
+	   unsigned HOST_WIDE_INT shiftc = tree_to_uhwi (@3);
+	   unsigned HOST_WIDE_INT newsize = size - shiftc;
+	   tree nsize = wide_int_to_tree (bitsizetype, newsize);
+	   tree ntype
+	     = build_nonstandard_integer_type (newsize, 1); }
+    (if (ntype)
+     (convert:type (BIT_FIELD_REF:ntype @0 { nsize; } (op @2 @3))))))))
+
 (simplify
  (BIT_FIELD_REF (BIT_FIELD_REF @0 @1 @2) @3 @4)
  (BIT_FIELD_REF @0 @3 { const_binop (PLUS_EXPR, bitsizetype, @2, @4); }))