Refactor disassembly code

This patch addes class gdb_disassembler, and refactor
code to use it.  The gdb_disassembler object is saved
in disassember_info.application_data.  However,
disassember_info.application_data is already used by
gdb for arm, mips spu, and scm-disasm.  In arm and mips,
.application_data is gdbarch, but we can still get gdbarch
from gdb_disassember.

The use of application_data in spu is a little bit
complicated.  It creates its own disassemble_info, and
save spu_dis_asm_data in .application_data.  This will
overwrite the pointer to gdb_disassembler, so we need
to find another place to save spu_dis_asm_data.  I
extend disassemble_info, and put "id" there.

gdb:

2017-01-26  Pedro Alves  <palves@redhat.com>
	    Yao Qi  <yao.qi@linaro.org>

	* arm-tdep.c: Include "disasm.h".
	(gdb_print_insn_arm): Update code to get gdbarch.
	* disasm.c (dis_asm_read_memory): Change it to
	gdb_disassembler::dis_asm_read_memory.
	(dis_asm_memory_error): Likewise.
	(dis_asm_print_address): Likewise.
	(gdb_pretty_print_insn): Change it to
	gdb_disassembler::pretty_print_insn.
	(dump_insns): Add one argument gdb_disassemlber.  All
	callers updated.
	(do_mixed_source_and_assembly_deprecated): Likewise.
	(do_mixed_source_and_assembly): Likewise.
	(do_assembly_only): Likewise.
	(gdb_disassembler::gdb_disassembler): New.
	(gdb_disassembler::print_insn): New.
	* disasm.h (class gdb_disassembler): New.
	(gdb_pretty_print_insn): Remove declaration.
	(gdb_disassemble_info): Likewise.
	* guile/scm-disasm.c (class gdbscm_disassembler): New.
	(gdbscm_disasm_read_memory_worker): Update.
	(gdbscm_disasm_read_memory): Update.
	(gdbscm_disasm_memory_error): Remove.
	(gdbscm_disasm_print_address): Remove.
	(gdbscm_disassembler::gdbscm_disassembler): New.
	(gdbscm_print_insn_from_port): Update.
	* mips-tdep.c: Include disasm.h.
	(gdb_print_insn_mips): Update code to get gdbarch.
	* record-btrace.c (btrace_insn_history): Update.
	* spu-tdep.c: Include disasm.h.
	(struct spu_dis_asm_data): Remove.
	(struct spu_dis_asm_info): New.
	(spu_dis_asm_print_address): Use spu_dis_asm_info to get
	SPU id.
	(gdb_print_insn_spu): Cast disassemble_info to
	spu_dis_asm_info.

1 files changed, 20 insertions, 57 deletions

diff --git a/gdb/guile/scm-disasm.c b/gdb/guile/scm-disasm.c
index d06c481..25cae5a 100644
--- a/gdb/guile/scm-disasm.c
+++ b/gdb/guile/scm-disasm.c
@@ -37,11 +37,13 @@ static SCM address_symbol;
 static SCM asm_symbol;
 static SCM length_symbol;
 
-/* Struct used to pass "application data" in disassemble_info.  */
-
-struct gdbscm_disasm_data
+class gdbscm_disassembler : public gdb_disassembler
 {
-  struct gdbarch *gdbarch;
+public:
+  gdbscm_disassembler (struct gdbarch *gdbarch,
+		       struct ui_file *stream,
+		       SCM port, ULONGEST offset);
+
   SCM port;
   /* The offset of the address of the first instruction in PORT.  */
   ULONGEST offset;
@@ -55,7 +57,7 @@ struct gdbscm_disasm_read_data
   bfd_vma memaddr;
   bfd_byte *myaddr;
   unsigned int length;
-  struct disassemble_info *dinfo;
+  gdbscm_disassembler *dinfo;
 };
 
 /* Subroutine of gdbscm_arch_disassemble to simplify it.
@@ -81,13 +83,11 @@ gdbscm_disasm_read_memory_worker (void *datap)
 {
   struct gdbscm_disasm_read_data *data
     = (struct gdbscm_disasm_read_data *) datap;
-  struct disassemble_info *dinfo = data->dinfo;
-  struct gdbscm_disasm_data *disasm_data
-    = (struct gdbscm_disasm_data *) dinfo->application_data;
-  SCM seekto, newpos, port = disasm_data->port;
+  gdbscm_disassembler *dinfo = data->dinfo;
+  SCM seekto, newpos, port = dinfo->port;
   size_t bytes_read;
 
-  seekto = gdbscm_scm_from_ulongest (data->memaddr - disasm_data->offset);
+  seekto = gdbscm_scm_from_ulongest (data->memaddr - dinfo->offset);
   newpos = scm_seek (port, seekto, scm_from_int (SEEK_SET));
   if (!scm_is_eq (seekto, newpos))
     return "seek error";
@@ -108,13 +108,15 @@ gdbscm_disasm_read_memory (bfd_vma memaddr, bfd_byte *myaddr,
 			   unsigned int length,
 			   struct disassemble_info *dinfo)
 {
+  gdbscm_disassembler *self
+    = static_cast<gdbscm_disassembler *> (dinfo->application_data);
   struct gdbscm_disasm_read_data data;
   const char *status;
 
   data.memaddr = memaddr;
   data.myaddr = myaddr;
   data.length = length;
-  data.dinfo = dinfo;
+  data.dinfo = self;
 
   status = gdbscm_with_guile (gdbscm_disasm_read_memory_worker, &data);
 
@@ -123,30 +125,12 @@ gdbscm_disasm_read_memory (bfd_vma memaddr, bfd_byte *myaddr,
   return status != NULL ? -1 : 0;
 }
 
-/* disassemble_info.memory_error_func for gdbscm_print_insn_from_port.
-   Technically speaking, we don't need our own memory_error_func,
-   but to not provide one would leave a subtle dependency in the code.
-   This function exists to keep a clear boundary.  */
-
-static void
-gdbscm_disasm_memory_error (int status, bfd_vma memaddr,
-			    struct disassemble_info *info)
-{
-  memory_error (TARGET_XFER_E_IO, memaddr);
-}
-
-/* disassemble_info.print_address_func for gdbscm_print_insn_from_port.
-   Since we need to use our own application_data value, we need to supply
-   this routine as well.  */
-
-static void
-gdbscm_disasm_print_address (bfd_vma addr, struct disassemble_info *info)
+gdbscm_disassembler::gdbscm_disassembler (struct gdbarch *gdbarch,
+					  struct ui_file *stream,
+					  SCM port_, ULONGEST offset_)
+  : gdb_disassembler (gdbarch, stream, gdbscm_disasm_read_memory),
+    port (port_), offset (offset_)
 {
-  struct gdbscm_disasm_data *data
-    = (struct gdbscm_disasm_data *) info->application_data;
-  struct gdbarch *gdbarch = data->gdbarch;
-
-  print_address (gdbarch, addr, (struct ui_file *) info->stream);
 }
 
 /* Subroutine of gdbscm_arch_disassemble to simplify it.
@@ -164,30 +148,9 @@ gdbscm_print_insn_from_port (struct gdbarch *gdbarch,
 			     SCM port, ULONGEST offset, CORE_ADDR memaddr,
 			     struct ui_file *stream, int *branch_delay_insns)
 {
-  struct disassemble_info di;
-  int length;
-  struct gdbscm_disasm_data data;
-
-  di = gdb_disassemble_info (gdbarch, stream);
-  data.gdbarch = gdbarch;
-  data.port = port;
-  data.offset = offset;
-  di.application_data = &data;
-  di.read_memory_func = gdbscm_disasm_read_memory;
-  di.memory_error_func = gdbscm_disasm_memory_error;
-  di.print_address_func = gdbscm_disasm_print_address;
-
-  length = gdbarch_print_insn (gdbarch, memaddr, &di);
-
-  if (branch_delay_insns)
-    {
-      if (di.insn_info_valid)
-	*branch_delay_insns = di.branch_delay_insns;
-      else
-	*branch_delay_insns = 0;
-    }
+  gdbscm_disassembler di (gdbarch, stream, port, offset);
 
-  return length;
+  return di.print_insn (memaddr, branch_delay_insns);
 }
 
 /* (arch-disassemble <gdb:arch> address