[PATCH v3 1/2] RISC-V: Better support for long instructions (disassembler)

[Tsukasa OI <research_trasio@irq.a4lg.com>]

From: Tsukasa OI <research_trasio@irq.a4lg.com>

Commit bb996692bd96 ("RISC-V/gas: allow generating up to 176-bit
instructions with .insn") tried to start supporting long instructions but
it was insufficient.

1.  On the disassembler, disassembler dump was limited up to 64-bit.
    For long (unknown) instructions, instruction bits are incorrectly
    zeroed out.

To solve these problems, this commit adds packet argument to support dumping
instructions longer than 64-bits.  This commit will be tested on the next
commit "RISC-V: Better support for long instructions (assembler)".

opcodes/ChangeLog:

	* riscv-dis.c (riscv_disassemble_insn): Print unknown instruction
	using the new argument packet.
	(riscv_disassemble_data): Add unused argument packet.
	(print_insn_riscv): Pass packet to the disassemble function.
---
 opcodes/riscv-dis.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/opcodes/riscv-dis.c b/opcodes/riscv-dis.c
index 3a31647a2f80..59ebbaf13417 100644
--- a/opcodes/riscv-dis.c
+++ b/opcodes/riscv-dis.c
@@ -641,7 +641,10 @@ print_insn_args (const char *oparg, insn_t l, bfd_vma pc, disassemble_info *info
    this is little-endian code.  */
 
 static int
-riscv_disassemble_insn (bfd_vma memaddr, insn_t word, disassemble_info *info)
+riscv_disassemble_insn (bfd_vma memaddr,
+			insn_t word,
+			const bfd_byte *packet,
+			disassemble_info *info)
 {
   const struct riscv_opcode *op;
   static bool init = false;
@@ -806,8 +809,7 @@ riscv_disassemble_insn (bfd_vma memaddr, insn_t word, disassemble_info *info)
 					    ", ");
 	    (*info->fprintf_styled_func) (info->stream, dis_style_immediate,
 					  "0x%02x",
-					  (unsigned int) (word & 0xff));
-            word >>= 8;
+					  (unsigned int) (*packet++));
           }
       }
       break;
@@ -983,6 +985,7 @@ riscv_data_length (bfd_vma memaddr,
 static int
 riscv_disassemble_data (bfd_vma memaddr ATTRIBUTE_UNUSED,
 			insn_t data,
+			const bfd_byte *packet ATTRIBUTE_UNUSED,
 			disassemble_info *info)
 {
   info->display_endian = info->endian;
@@ -1037,7 +1040,7 @@ print_insn_riscv (bfd_vma memaddr, struct disassemble_info *info)
   bfd_vma dump_size;
   int status;
   enum riscv_seg_mstate mstate;
-  int (*riscv_disassembler) (bfd_vma, insn_t, struct disassemble_info *);
+  int (*riscv_disassembler) (bfd_vma, insn_t, const bfd_byte*, struct disassemble_info *);
 
   if (info->disassembler_options != NULL)
     {
@@ -1081,7 +1084,7 @@ print_insn_riscv (bfd_vma memaddr, struct disassemble_info *info)
     }
   insn = (insn_t) bfd_get_bits (packet, dump_size * 8, false);
 
-  return (*riscv_disassembler) (memaddr, insn, info);
+  return (*riscv_disassembler) (memaddr, insn, packet, info);
 }
 
 disassembler_ftype
-- 
2.38.1