[PATCH v5 1/4] RISC-V: Print highest address on disassembler

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

This patch makes possible to print the highest address (0xffffffff on RV32,
0xffffffff_ffffffff on RV64).  This is particularly useful if the highest
address space is used for I/O registers and corresponding symbols
are defined.

opcodes/ChangeLog:

	* riscv-dis.c (struct riscv_private_data): Add `to_print_addr' and
	`has_gp' to enable printing the highest address.
	(maybe_print_address): Utilize `to_print_addr' and `has_gp'.
	(riscv_disassemble_insn): Likewise.
---
 opcodes/riscv-dis.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/opcodes/riscv-dis.c b/opcodes/riscv-dis.c
index 164fd209dbd..c6d80c3ba49 100644
--- a/opcodes/riscv-dis.c
+++ b/opcodes/riscv-dis.c
@@ -52,6 +52,8 @@ struct riscv_private_data
   bfd_vma gp;
   bfd_vma print_addr;
   bfd_vma hi_addr[OP_MASK_RD + 1];
+  bool to_print_addr;
+  bool has_gp;
 };
 
 /* Used for mapping symbols.  */
@@ -177,10 +179,13 @@ maybe_print_address (struct riscv_private_data *pd, int base_reg, int offset,
       pd->print_addr = (base_reg != 0 ? pd->hi_addr[base_reg] : 0) + offset;
       pd->hi_addr[base_reg] = -1;
     }
-  else if (base_reg == X_GP && pd->gp != (bfd_vma)-1)
+  else if (base_reg == X_GP && pd->has_gp)
     pd->print_addr = pd->gp + offset;
   else if (base_reg == X_TP || base_reg == 0)
     pd->print_addr = offset;
+  else
+    return;
+  pd->to_print_addr = true;
 
   /* Sign-extend a 32-bit value to a 64-bit value.  */
   if (wide)
@@ -595,14 +600,19 @@ riscv_disassemble_insn (bfd_vma memaddr, insn_t word, disassemble_info *info)
       int i;
 
       pd = info->private_data = xcalloc (1, sizeof (struct riscv_private_data));
-      pd->gp = -1;
-      pd->print_addr = -1;
+      pd->gp = 0;
+      pd->print_addr = 0;
       for (i = 0; i < (int)ARRAY_SIZE (pd->hi_addr); i++)
 	pd->hi_addr[i] = -1;
+      pd->to_print_addr = false;
+      pd->has_gp = false;
 
       for (i = 0; i < info->symtab_size; i++)
 	if (strcmp (bfd_asymbol_name (info->symtab[i]), RISCV_GP_SYMBOL) == 0)
-	  pd->gp = bfd_asymbol_value (info->symtab[i]);
+	  {
+	    pd->gp = bfd_asymbol_value (info->symtab[i]);
+	    pd->has_gp = true;
+	  }
     }
   else
     pd = info->private_data;
@@ -662,13 +672,13 @@ riscv_disassemble_insn (bfd_vma memaddr, insn_t word, disassemble_info *info)
 	  print_insn_args (op->args, word, memaddr, info);
 
 	  /* Try to disassemble multi-instruction addressing sequences.  */
-	  if (pd->print_addr != (bfd_vma)-1)
+	  if (pd->to_print_addr)
 	    {
 	      info->target = pd->print_addr;
 	      (*info->fprintf_styled_func)
 		(info->stream, dis_style_comment_start, " # ");
 	      (*info->print_address_func) (info->target, info);
-	      pd->print_addr = -1;
+	      pd->to_print_addr = false;
 	    }
 
 	  /* Finish filling out insn_info fields.  */
-- 
2.34.1