--- a/binutils/testsuite/binutils-all/riscv/unknown.d
+++ b/binutils/testsuite/binutils-all/riscv/unknown.d
@@ -1,11 +1,11 @@
 #as: -march=rv32ic
 #objdump: -d
 # Test the disassembly of unknown instruction encodings, specifically,
-# ensure that we generate a .?byte opcode.
+# ensure that we generate a .insn directive.
 
 #...
 Disassembly of section \.text:
 
 [0-9a-f]+ <\.text>:
-   [0-9a-f]+:	0052018b          	\.4byte	0x52018b
-   [0-9a-f]+:	9c45                	\.2byte	0x9c45
+   [0-9a-f]+:	0052018b          	\.insn	4, 0x0052018b
+   [0-9a-f]+:	9c45                	\.insn	2, 0x9c45
--- a/gas/testsuite/gas/riscv/insn.d
+++ b/gas/testsuite/gas/riscv/insn.d
@@ -92,25 +92,25 @@ Disassembly of section .text:
 [^:]+:[ 	]+607f 0000 0000 0000[ 	]+[._a-z].*
 [^:]+:[ 	]+0000 0000 0000 0000 ?
 [^:]+:[ 	]+0000 0000 0000 ?
-[^:]+:[ 	]+007f 0000 0000 0000[ 	]+\.byte[ 	]+0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80
+[^:]+:[ 	]+007f 0000 0000 0000[ 	]+\.insn[ 	]+10, +0x8000000000000000007f
 [^:]+:[ 	]+8000 ?
-[^:]+:[ 	]+007f 0000 0000 0000[ 	]+\.byte[ 	]+0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80
+[^:]+:[ 	]+007f 0000 0000 0000[ 	]+\.insn[ 	]+10, +0x8000000000000000007f
 [^:]+:[ 	]+8000 ?
-[^:]+:[ 	]+607f 89ab 4567 0123[ 	]+\.byte[ 	]+0x7f, 0x60, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+[^:]+:[ 	]+607f 89ab 4567 0123[ 	]+\.insn[ 	]+22, 0xfedcba98765432100123456789ab607f
 [^:]+:[ 	]+3210 7654 ba98 fedc ?
 [^:]+:[ 	]+0000 0000 0000 ?
-[^:]+:[ 	]+607f 89ab 4567 0123[ 	]+\.byte[ 	]+0x7f, 0x60, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+[^:]+:[ 	]+607f 89ab 4567 0123[ 	]+\.insn[ 	]+22, 0xfedcba98765432100123456789ab607f
 [^:]+:[ 	]+3210 7654 ba98 fedc ?
 [^:]+:[ 	]+0000 0000 0000 ?
-[^:]+:[ 	]+607f 33cc 55aa cdef[ 	]+\.byte[ 	]+0x7f, 0x60, 0xcc, 0x33, 0xaa, 0x55, 0xef, 0xcd, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0x00
+[^:]+:[ 	]+607f 33cc 55aa cdef[ 	]+\.insn[ 	]+22, 0x00dcba98765432100123456789abcdef55aa33cc607f
 [^:]+:[ 	]+89ab 4567 0123 3210 ?
 [^:]+:[ 	]+7654 ba98 00dc ?
-[^:]+:[ 	]+607f 33cc 55aa cdef[ 	]+\.byte[ 	]+0x7f, 0x60, 0xcc, 0x33, 0xaa, 0x55, 0xef, 0xcd, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0x00
+[^:]+:[ 	]+607f 33cc 55aa cdef[ 	]+\.insn[ 	]+22, 0x00dcba98765432100123456789abcdef55aa33cc607f
 [^:]+:[ 	]+89ab 4567 0123 3210 ?
 [^:]+:[ 	]+7654 ba98 00dc ?
-[^:]+:[ 	]+607f 33cc 55aa cdef[ 	]+\.byte[ 	]+0x7f, 0x60, 0xcc, 0x33, 0xaa, 0x55, 0xef, 0xcd, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0xfe
+[^:]+:[ 	]+607f 33cc 55aa cdef[ 	]+\.insn[ 	]+22, 0xfedcba98765432100123456789abcdef55aa33cc607f
 [^:]+:[ 	]+89ab 4567 0123 3210 ?
 [^:]+:[ 	]+7654 ba98 fedc ?
-[^:]+:[ 	]+607f 33cc 55aa cdef[ 	]+\.byte[ 	]+0x7f, 0x60, 0xcc, 0x33, 0xaa, 0x55, 0xef, 0xcd, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0xfe
+[^:]+:[ 	]+607f 33cc 55aa cdef[ 	]+\.insn[ 	]+22, 0xfedcba98765432100123456789abcdef55aa33cc607f
 [^:]+:[ 	]+89ab 4567 0123 3210 ?
 [^:]+:[ 	]+7654 ba98 fedc ?
--- a/gas/testsuite/gas/riscv/insn-na.d
+++ b/gas/testsuite/gas/riscv/insn-na.d
@@ -73,11 +73,11 @@ Disassembly of section .text:
 [^:]+:[ 	]+007f 0000 0000 0000 0000[ 	]+[._a-z].*
 [^:]+:[ 	]+0000107f 00000000 00000000[ 	]+[._a-z].*
 [^:]+:[ 	]+607f 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000[ 	]+[._a-z].*
-[^:]+:[ 	]+007f 0000 0000 0000 8000[ 	]+\.byte[ 	]+0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80
-[^:]+:[ 	]+007f 0000 0000 0000 8000[ 	]+\.byte[ 	]+0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80
-[^:]+:[ 	]+607f 89ab 4567 0123 3210 7654 ba98 fedc 0000 0000 0000[ 	]+\.byte[ 	]+0x7f, 0x60, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
-[^:]+:[ 	]+607f 89ab 4567 0123 3210 7654 ba98 fedc 0000 0000 0000[ 	]+\.byte[ 	]+0x7f, 0x60, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
-[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 00dc[ 	]+\.byte[ 	]+0x7f, 0x60, 0xcc, 0x33, 0xaa, 0x55, 0xef, 0xcd, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0x00
-[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 00dc[ 	]+\.byte[ 	]+0x7f, 0x60, 0xcc, 0x33, 0xaa, 0x55, 0xef, 0xcd, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0x00
-[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 fedc[ 	]+\.byte[ 	]+0x7f, 0x60, 0xcc, 0x33, 0xaa, 0x55, 0xef, 0xcd, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0xfe
-[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 fedc[ 	]+\.byte[ 	]+0x7f, 0x60, 0xcc, 0x33, 0xaa, 0x55, 0xef, 0xcd, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01, 0x10, 0x32, 0x54, 0x76, 0x98, 0xba, 0xdc, 0xfe
+[^:]+:[ 	]+007f 0000 0000 0000 8000[ 	]+\.insn[ 	]+10, +0x8000000000000000007f
+[^:]+:[ 	]+007f 0000 0000 0000 8000[ 	]+\.insn[ 	]+10, +0x8000000000000000007f
+[^:]+:[ 	]+607f 89ab 4567 0123 3210 7654 ba98 fedc 0000 0000 0000[ 	]+\.insn[ 	]+22, 0xfedcba98765432100123456789ab607f
+[^:]+:[ 	]+607f 89ab 4567 0123 3210 7654 ba98 fedc 0000 0000 0000[ 	]+\.insn[ 	]+22, 0xfedcba98765432100123456789ab607f
+[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 00dc[ 	]+\.insn[ 	]+22, 0x00dcba98765432100123456789abcdef55aa33cc607f
+[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 00dc[ 	]+\.insn[ 	]+22, 0x00dcba98765432100123456789abcdef55aa33cc607f
+[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 fedc[ 	]+\.insn[ 	]+22, 0xfedcba98765432100123456789abcdef55aa33cc607f
+[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 fedc[ 	]+\.insn[ 	]+22, 0xfedcba98765432100123456789abcdef55aa33cc607f
--- a/opcodes/riscv-dis.c
+++ b/opcodes/riscv-dis.c
@@ -650,7 +650,8 @@ riscv_disassemble_insn (bfd_vma memaddr,
   static bool init = false;
   static const struct riscv_opcode *riscv_hash[OP_MASK_OP + 1];
   struct riscv_private_data *pd;
-  int insnlen;
+  int insnlen, i;
+  bool printed;
 
 #define OP_HASH_IDX(i) ((i) & (riscv_insn_length (i) == 2 ? 0x3 : OP_MASK_OP))
 
@@ -666,8 +667,6 @@ riscv_disassemble_insn (bfd_vma memaddr,
 
   if (info->private_data == NULL)
     {
-      int i;
-
       pd = info->private_data = xcalloc (1, sizeof (struct riscv_private_data));
       pd->gp = 0;
       pd->print_addr = 0;
@@ -783,37 +782,28 @@ riscv_disassemble_insn (bfd_vma memaddr,
 	}
     }
 
-  /* We did not find a match, so just print the instruction bits.  */
+  /* We did not find a match, so just print the instruction bits in
+     the shape of an assembler .insn directive.  */
   info->insn_type = dis_noninsn;
-  switch (insnlen)
+  (*info->fprintf_styled_func)
+    (info->stream, dis_style_assembler_directive, ".insn");
+  (*info->fprintf_styled_func) (info->stream, dis_style_text, "\t");
+  (*info->fprintf_styled_func) (info->stream, dis_style_immediate,
+				"%d", insnlen);
+  (*info->fprintf_styled_func) (info->stream, dis_style_text, ", ");
+  (*info->fprintf_styled_func) (info->stream, dis_style_immediate, "0x");
+  for (i = insnlen, printed = false; i >= 2; )
     {
-    case 2:
-    case 4:
-    case 8:
-      (*info->fprintf_styled_func)
-	(info->stream, dis_style_assembler_directive, ".%dbyte", insnlen);
-      (*info->fprintf_styled_func) (info->stream, dis_style_text, "\t");
+      i -= 2;
+      word = bfd_get_bits (packet + i, 16, false);
+      if (!word && !printed)
+	continue;
+
       (*info->fprintf_styled_func) (info->stream, dis_style_immediate,
-				    "0x%llx", (unsigned long long) word);
-      break;
-    default:
-      {
-        int i;
-	(*info->fprintf_styled_func)
-	  (info->stream, dis_style_assembler_directive, ".byte");
-	(*info->fprintf_styled_func) (info->stream, dis_style_text, "\t");
-        for (i = 0; i < insnlen; ++i)
-          {
-            if (i > 0)
-	      (*info->fprintf_styled_func) (info->stream, dis_style_text,
-					    ", ");
-	    (*info->fprintf_styled_func) (info->stream, dis_style_immediate,
-					  "0x%02x",
-					  (unsigned int) (*packet++));
-          }
-      }
-      break;
+				    "%04x", (unsigned int) word);
+      printed = true;
     }
+
   return insnlen;
 }
 
