[PATCH] RISC-V: don't disassemble unrecognized insns as .byte

[Jan Beulich]

Insn width granularity being 16 bits, produce 16 bits of data per output
element for the non-special-cased insn widths. Besides being slightly
more natural (in particular having the first element carry everything
that's needed for determining insn length), this is also slightly more
compact.
---
I think output would be even more neat if .<N>byte were suppressed when
generic code already prints the raw insn (or maybe something like
<unknown> was printed instead).

As to the special case code for 2-, 4-, and 8-byte insns: Any thoughts
towards zero-padding the numbers there as well? That would make yet more
noticable what the insn width is; in particular - see e.g. ".8byte 0x3f"
in full disassembly of the testcases modified here - it would avoid the
value looking like it was for a more narrow one.

Taking it yet one step further - how about printing unknown insns as
".insn ...", matching what gas would consume?

--- a/gas/testsuite/gas/riscv/insn-na.d
+++ b/gas/testsuite/gas/riscv/insn-na.d
@@ -76,11 +76,11 @@ 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[ 	]+\.2byte[ 	]+0x007f, 0x0000, 0x0000, 0x0000, 0x8000
+[^:]+:[ 	]+007f 0000 0000 0000 8000[ 	]+\.2byte[ 	]+0x007f, 0x0000, 0x0000, 0x0000, 0x8000
+[^:]+:[ 	]+607f 89ab 4567 0123 3210 7654 ba98 fedc 0000 0000 0000[ 	]+\.2byte[ 	]+0x607f, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0xfedc, 0x0000, 0x0000, 0x0000
+[^:]+:[ 	]+607f 89ab 4567 0123 3210 7654 ba98 fedc 0000 0000 0000[ 	]+\.2byte[ 	]+0x607f, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0xfedc, 0x0000, 0x0000, 0x0000
+[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 00dc[ 	]+\.2byte[ 	]+0x607f, 0x33cc, 0x55aa, 0xcdef, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0x00dc
+[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 00dc[ 	]+\.2byte[ 	]+0x607f, 0x33cc, 0x55aa, 0xcdef, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0x00dc
+[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 fedc[ 	]+\.2byte[ 	]+0x607f, 0x33cc, 0x55aa, 0xcdef, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0xfedc
+[^:]+:[ 	]+607f 33cc 55aa cdef 89ab 4567 0123 3210 7654 ba98 fedc[ 	]+\.2byte[ 	]+0x607f, 0x33cc, 0x55aa, 0xcdef, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0xfedc
--- a/gas/testsuite/gas/riscv/insn.d
+++ b/gas/testsuite/gas/riscv/insn.d
@@ -95,25 +95,25 @@ 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[ 	]+\.2byte[ 	]+0x007f, 0x0000, 0x0000, 0x0000, 0x8000
 [^:]+:[ 	]+8000 ?
-[^:]+:[ 	]+007f 0000 0000 0000[ 	]+\.byte[ 	]+0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80
+[^:]+:[ 	]+007f 0000 0000 0000[ 	]+\.2byte[ 	]+0x007f, 0x0000, 0x0000, 0x0000, 0x8000
 [^:]+:[ 	]+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[ 	]+\.2byte[ 	]+0x607f, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0xfedc, 0x0000, 0x0000, 0x0000
 [^:]+:[ 	]+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[ 	]+\.2byte[ 	]+0x607f, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0xfedc, 0x0000, 0x0000, 0x0000
 [^:]+:[ 	]+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[ 	]+\.2byte[ 	]+0x607f, 0x33cc, 0x55aa, 0xcdef, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0x00dc
 [^:]+:[ 	]+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[ 	]+\.2byte[ 	]+0x607f, 0x33cc, 0x55aa, 0xcdef, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0x00dc
 [^:]+:[ 	]+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[ 	]+\.2byte[ 	]+0x607f, 0x33cc, 0x55aa, 0xcdef, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0xfedc
 [^:]+:[ 	]+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[ 	]+\.2byte[ 	]+0x607f, 0x33cc, 0x55aa, 0xcdef, 0x89ab, 0x4567, 0x0123, 0x3210, 0x7654, 0xba98, 0xfedc
 [^:]+:[ 	]+89ab 4567 0123 3210 ?
 [^:]+:[ 	]+7654 ba98 fedc ?
--- a/opcodes/riscv-dis.c
+++ b/opcodes/riscv-dis.c
@@ -800,16 +800,16 @@ riscv_disassemble_insn (bfd_vma memaddr,
       {
         int i;
 	(*info->fprintf_styled_func)
-	  (info->stream, dis_style_assembler_directive, ".byte");
+	  (info->stream, dis_style_assembler_directive, ".2byte");
 	(*info->fprintf_styled_func) (info->stream, dis_style_text, "\t");
-        for (i = 0; i < insnlen; ++i)
+        for (i = 0; i < insnlen; i += 2)
           {
             if (i > 0)
 	      (*info->fprintf_styled_func) (info->stream, dis_style_text,
 					    ", ");
+	    word = bfd_get_bits (packet + i, 16, false);
 	    (*info->fprintf_styled_func) (info->stream, dis_style_immediate,
-					  "0x%02x",
-					  (unsigned int) (*packet++));
+					  "0x%04x", (unsigned int) word);
           }
       }
       break;