[PATCH 1/6] Refactor disassembler selection

[Yao Qi <qiyaoltc@gmail.com>]

Nowadays, opcodes/disassemble.c:disassembler selects the proper
disassembler according to ABFD only.  However, it actually
selects disassemblers according to arch, mach, endianess, and
abfd.  This patch adds them to the parameters of disassembler,
so that its caller can still select disassemblers in case that
abfd is NULL (a typical case in GDB).

There isn't any functionality change.

binutils:

2017-05-15  Yao Qi  <yao.qi@linaro.org>

	* objdump.c (disassemble_data): Caller update.

include:

2017-05-15  Yao Qi  <yao.qi@linaro.org>

	* dis-asm.h (disassembler): Update declaration.

opcodes:

2017-05-15  Yao Qi  <yao.qi@linaro.org>

	* disassemble.c (disassembler): Add arguments a, big and mach.
	Use them.

sim/common:

2017-05-15  Yao Qi  <yao.qi@linaro.org>

	* sim-trace.c (trace_disasm): Caller update.
---
 binutils/objdump.c     |  4 +++-
 include/dis-asm.h      |  8 ++++++--
 opcodes/disassemble.c  | 41 ++++++++++++++++++++++++++---------------
 sim/common/sim-trace.c |  6 +++++-
 4 files changed, 40 insertions(+), 19 deletions(-)

diff --git a/binutils/objdump.c b/binutils/objdump.c
index 5972da1..81d47a0 100644
--- a/binutils/objdump.c
+++ b/binutils/objdump.c
@@ -2386,7 +2386,9 @@ disassemble_data (bfd *abfd)
     }
 
   /* Use libopcodes to locate a suitable disassembler.  */
-  aux.disassemble_fn = disassembler (abfd);
+  aux.disassemble_fn = disassembler (bfd_get_arch (abfd),
+				     bfd_big_endian (abfd),
+				     bfd_get_mach (abfd), abfd);
   if (!aux.disassemble_fn)
     {
       non_fatal (_("can't disassemble for architecture %s\n"),
diff --git a/include/dis-asm.h b/include/dis-asm.h
index 6f1801d..dd93504 100644
--- a/include/dis-asm.h
+++ b/include/dis-asm.h
@@ -354,8 +354,12 @@ extern const disasm_options_t *disassembler_options_powerpc (void);
 extern const disasm_options_t *disassembler_options_arm (void);
 extern const disasm_options_t *disassembler_options_s390 (void);
 
-/* Fetch the disassembler for a given BFD, if that support is available.  */
-extern disassembler_ftype disassembler (bfd *);
+/* Fetch the disassembler for a given architecture ARC, endianess (big
+   endian if BIG is true), bfd_mach value MACH, and ABFD, if that support
+   is available.  ABFD may be NULL.  */
+extern disassembler_ftype disassembler (enum bfd_architecture arc,
+					bfd_boolean big, unsigned long mach,
+					bfd *abfd);
 
 /* Amend the disassemble_info structure as necessary for the target architecture.
    Should only be called after initialising the info->arch field.  */
diff --git a/opcodes/disassemble.c b/opcodes/disassemble.c
index dd7d3a3..e79b5c7 100644
--- a/opcodes/disassemble.c
+++ b/opcodes/disassemble.c
@@ -21,6 +21,7 @@
 #include "sysdep.h"
 #include "dis-asm.h"
 #include "safe-ctype.h"
+#include <assert.h>
 
 #ifdef ARCH_all
 #define ARCH_aarch64
@@ -109,11 +110,22 @@
 #endif
 
 disassembler_ftype
-disassembler (bfd *abfd)
+disassembler (enum bfd_architecture a, bfd_boolean big, unsigned long mach,
+	      bfd *abfd)
 {
-  enum bfd_architecture a = bfd_get_arch (abfd);
   disassembler_ftype disassemble;
 
+  if (abfd != NULL)
+    {
+      /* Do some asserts that the first three parameters should equal
+	 to what we can get from ABFD.  On the other hand, these
+	 asserts help removing some compiler errors on unused
+	 parameter.  */
+      assert (a == bfd_get_arch (abfd));
+      assert (big == bfd_big_endian (abfd));
+      assert (mach == bfd_get_mach (abfd));
+    }
+
   switch (a)
     {
       /* If you add a case to this table, also add it to the
@@ -135,7 +147,7 @@ disassembler (bfd *abfd)
 #endif
 #ifdef ARCH_arm
     case bfd_arch_arm:
-      if (bfd_big_endian (abfd))
+      if (big)
 	disassemble = print_insn_big_arm;
       else
 	disassemble = print_insn_little_arm;
@@ -184,13 +196,12 @@ disassembler (bfd *abfd)
 #endif
 #ifdef ARCH_h8300
     case bfd_arch_h8300:
-      if (bfd_get_mach (abfd) == bfd_mach_h8300h
-	  || bfd_get_mach (abfd) == bfd_mach_h8300hn)
+      if (mach == bfd_mach_h8300h || mach == bfd_mach_h8300hn)
 	disassemble = print_insn_h8300h;
-      else if (bfd_get_mach (abfd) == bfd_mach_h8300s
-	       || bfd_get_mach (abfd) == bfd_mach_h8300sn
-	       || bfd_get_mach (abfd) == bfd_mach_h8300sx
-	       || bfd_get_mach (abfd) == bfd_mach_h8300sxn)
+      else if (mach == bfd_mach_h8300s
+	       || mach == bfd_mach_h8300sn
+	       || mach == bfd_mach_h8300sx
+	       || mach == bfd_mach_h8300sxn)
 	disassemble = print_insn_h8300s;
       else
 	disassemble = print_insn_h8300;
@@ -326,7 +337,7 @@ disassembler (bfd *abfd)
 #endif
 #ifdef ARCH_mips
     case bfd_arch_mips:
-      if (bfd_big_endian (abfd))
+      if (big)
 	disassemble = print_insn_big_mips;
       else
 	disassemble = print_insn_little_mips;
@@ -349,7 +360,7 @@ disassembler (bfd *abfd)
 #endif
 #ifdef ARCH_nios2
     case bfd_arch_nios2:
-      if (bfd_big_endian (abfd))
+      if (big)
 	disassemble = print_insn_big_nios2;
       else
 	disassemble = print_insn_little_nios2;
@@ -372,7 +383,7 @@ disassembler (bfd *abfd)
 #endif
 #ifdef ARCH_powerpc
     case bfd_arch_powerpc:
-      if (bfd_big_endian (abfd))
+      if (big)
 	disassemble = print_insn_big_powerpc;
       else
 	disassemble = print_insn_little_powerpc;
@@ -390,7 +401,7 @@ disassembler (bfd *abfd)
 #endif
 #ifdef ARCH_rs6000
     case bfd_arch_rs6000:
-      if (bfd_get_mach (abfd) == bfd_mach_ppc_620)
+      if (mach == bfd_mach_ppc_620)
 	disassemble = print_insn_big_powerpc;
       else
 	disassemble = print_insn_rs6000;
@@ -413,7 +424,7 @@ disassembler (bfd *abfd)
 #endif
 #ifdef ARCH_score
     case bfd_arch_score:
-      if (bfd_big_endian (abfd))
+      if (big)
 	disassemble = print_insn_big_score;
       else
 	disassemble = print_insn_little_score;
@@ -507,7 +518,7 @@ disassembler (bfd *abfd)
 #endif
 #ifdef ARCH_z8k
     case bfd_arch_z8k:
-      if (bfd_get_mach(abfd) == bfd_mach_z8001)
+      if (mach == bfd_mach_z8001)
 	disassemble = print_insn_z8001;
       else
 	disassemble = print_insn_z8002;
diff --git a/sim/common/sim-trace.c b/sim/common/sim-trace.c
index da19b82..ff11d20 100644
--- a/sim/common/sim-trace.c
+++ b/sim/common/sim-trace.c
@@ -919,7 +919,11 @@ trace_disasm (SIM_DESC sd, sim_cpu *cpu, address_word addr)
   if (trace_data->dis_bfd != bfd)
     {
       trace_data->dis_bfd = bfd;
-      trace_data->disassembler = disassembler (trace_data->dis_bfd);
+      trace_data->disassembler
+	= disassembler (bfd_get_arch (trace_data->dis_bfd),
+			bfd_big_endian (trace_data->dis_bfd),
+			bfd_get_mach (trace_data->dis_bfd),
+			trace_data->dis_bfd);
       INIT_DISASSEMBLE_INFO (*info, cpu, dis_printf);
       info->read_memory_func = dis_read;
       info->arch = bfd_get_arch (bfd);
-- 
1.9.1