Modify AArch64 Assembly and disassembly functions to be able to fail and report why.

This patch if the first patch in a series to add the ability to add constraints
to system registers that an instruction must adhere to in order for the register
to be usable with that instruction.

These constraints can also be used to disambiguate between registers with the
same encoding during disassembly.

This patch adds a new flags entry in the sysreg structures and ensures it is
filled in and read out during assembly/disassembly. It also adds the ability for
the assemble and disassemble functions to be able to gracefully fail and re-use
the existing error reporting infrastructure.

The return type of these functions are changed to a boolean to denote success or
failure and the error structure is passed around to them. This requires
aarch64-gen changes so a lot of the changes here are just mechanical.

gas/

	PR binutils/21446
	* config/tc-aarch64.c (parse_sys_reg): Return register flags.
	(parse_operands): Fill in register flags.

gdb/

	PR binutils/21446
	* aarch64-tdep.c (aarch64_analyze_prologue,
	aarch64_software_single_step, aarch64_displaced_step_copy_insn):
	Indicate not interested in errors.

include/

	PR binutils/21446
	* opcode/aarch64.h (aarch64_opnd_info): Change sysreg to struct.
	(aarch64_decode_insn): Accept error struct.

opcodes/

	PR binutils/21446
	* aarch64-asm.h (aarch64_insert_operand, aarch64_##x): Return boolean
	and take error struct.
	* aarch64-asm.c (aarch64_ext_regno, aarch64_ins_reglane,
	aarch64_ins_reglist, aarch64_ins_ldst_reglist,
	aarch64_ins_ldst_reglist_r, aarch64_ins_ldst_elemlist,
	aarch64_ins_advsimd_imm_shift, aarch64_ins_imm, aarch64_ins_imm_half,
	aarch64_ins_advsimd_imm_modified, aarch64_ins_fpimm,
	aarch64_ins_imm_rotate1, aarch64_ins_imm_rotate2, aarch64_ins_fbits,
	aarch64_ins_aimm, aarch64_ins_limm_1, aarch64_ins_limm,
	aarch64_ins_inv_limm, aarch64_ins_ft, aarch64_ins_addr_simple,
	aarch64_ins_addr_regoff, aarch64_ins_addr_offset, aarch64_ins_addr_simm,
	aarch64_ins_addr_simm10, aarch64_ins_addr_uimm12,
	aarch64_ins_simd_addr_post, aarch64_ins_cond, aarch64_ins_sysreg,
	aarch64_ins_pstatefield, aarch64_ins_sysins_op, aarch64_ins_barrier,
	aarch64_ins_prfop, aarch64_ins_hint, aarch64_ins_reg_extended,
	aarch64_ins_reg_shifted, aarch64_ins_sve_addr_ri_s4xvl,
	aarch64_ins_sve_addr_ri_s6xvl, aarch64_ins_sve_addr_ri_s9xvl,
	aarch64_ins_sve_addr_ri_s4, aarch64_ins_sve_addr_ri_u6,
	aarch64_ins_sve_addr_rr_lsl, aarch64_ins_sve_addr_rz_xtw,
	aarch64_ins_sve_addr_zi_u5, aarch64_ext_sve_addr_zz,
	aarch64_ins_sve_addr_zz_lsl, aarch64_ins_sve_addr_zz_sxtw,
	aarch64_ins_sve_addr_zz_uxtw, aarch64_ins_sve_aimm,
	aarch64_ins_sve_asimm, aarch64_ins_sve_index, aarch64_ins_sve_limm_mov,
	aarch64_ins_sve_quad_index, aarch64_ins_sve_reglist,
	aarch64_ins_sve_scale, aarch64_ins_sve_shlimm, aarch64_ins_sve_shrimm,
	aarch64_ins_sve_float_half_one, aarch64_ins_sve_float_half_two,
	aarch64_ins_sve_float_zero_one, aarch64_opcode_encode): Likewise.
	* aarch64-dis.h (aarch64_extract_operand, aarch64_##x): Likewise.
	* aarch64-dis.c (aarch64_ext_regno, aarch64_ext_reglane,
	aarch64_ext_reglist, aarch64_ext_ldst_reglist,
	aarch64_ext_ldst_reglist_r, aarch64_ext_ldst_elemlist,
	aarch64_ext_advsimd_imm_shift, aarch64_ext_imm, aarch64_ext_imm_half,
	aarch64_ext_advsimd_imm_modified, aarch64_ext_fpimm,
	aarch64_ext_imm_rotate1, aarch64_ext_imm_rotate2, aarch64_ext_fbits,
	aarch64_ext_aimm, aarch64_ext_limm_1, aarch64_ext_limm, decode_limm,
	aarch64_ext_inv_limm, aarch64_ext_ft, aarch64_ext_addr_simple,
	aarch64_ext_addr_regoff, aarch64_ext_addr_offset, aarch64_ext_addr_simm,
	aarch64_ext_addr_simm10, aarch64_ext_addr_uimm12,
	aarch64_ext_simd_addr_post, aarch64_ext_cond, aarch64_ext_sysreg,
	aarch64_ext_pstatefield, aarch64_ext_sysins_op, aarch64_ext_barrier,
	aarch64_ext_prfop, aarch64_ext_hint, aarch64_ext_reg_extended,
	aarch64_ext_reg_shifted, aarch64_ext_sve_addr_ri_s4xvl,
	aarch64_ext_sve_addr_ri_s6xvl, aarch64_ext_sve_addr_ri_s9xvl,
	aarch64_ext_sve_addr_ri_s4, aarch64_ext_sve_addr_ri_u6,
	aarch64_ext_sve_addr_rr_lsl, aarch64_ext_sve_addr_rz_xtw,
	aarch64_ext_sve_addr_zi_u5, aarch64_ext_sve_addr_zz,
	aarch64_ext_sve_addr_zz_lsl, aarch64_ext_sve_addr_zz_sxtw,
	aarch64_ext_sve_addr_zz_uxtw, aarch64_ext_sve_aimm,
	aarch64_ext_sve_asimm, aarch64_ext_sve_index, aarch64_ext_sve_limm_mov,
	aarch64_ext_sve_quad_index, aarch64_ext_sve_reglist,
	aarch64_ext_sve_scale, aarch64_ext_sve_shlimm, aarch64_ext_sve_shrimm,
	aarch64_ext_sve_float_half_one, aarch64_ext_sve_float_half_two,
	aarch64_ext_sve_float_zero_one, aarch64_opcode_decode): Likewise.
	(determine_disassembling_preference, aarch64_decode_insn,
	print_insn_aarch64_word, print_insn_data): Take errors struct.
	(print_insn_aarch64): Use errors.
	* aarch64-asm-2.c: Regenerate.
	* aarch64-dis-2.c: Regenerate.
	* aarch64-gen.c (print_operand_inserter): Use errors and change type to
	boolean in aarch64_insert_operan.
	(print_operand_extractor): Likewise.
	* aarch64-opc.c (aarch64_print_operand): Use sysreg struct.

2 files changed, 25 insertions, 10 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 358f033fd5..60a00f0da9 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,9 @@
+2018-05-15  Tamar Christina  <tamar.christina@arm.com>
+
+	PR binutils/21446
+	* config/tc-aarch64.c (parse_sys_reg): Return register flags.
+	(parse_operands): Fill in register flags.
+
 2018-05-14  Nick Clifton  <nickc@redhat.com>
 
 	* write.c (maybe_generate_build_notes): Generate notes on a
diff --git a/gas/config/tc-aarch64.c b/gas/config/tc-aarch64.c
index e673e12711..750025ac11 100644
--- a/gas/config/tc-aarch64.c
+++ b/gas/config/tc-aarch64.c
@@ -3934,7 +3934,8 @@ parse_barrier_psb (char **str,
 
 static int
 parse_sys_reg (char **str, struct hash_control *sys_regs,
-	       int imple_defined_p, int pstatefield_p)
+	       int imple_defined_p, int pstatefield_p,
+	       uint32_t* flags)
 {
   char *p, *q;
   char buf[32];
@@ -3965,6 +3966,8 @@ parse_sys_reg (char **str, struct hash_control *sys_regs,
 	  if (op0 > 3 || op1 > 7 || cn > 15 || cm > 15 || op2 > 7)
 	    return PARSE_FAIL;
 	  value = (op0 << 14) | (op1 << 11) | (cn << 7) | (cm << 3) | op2;
+	  if (flags)
+	    *flags = 0;
 	}
     }
   else
@@ -3979,6 +3982,8 @@ parse_sys_reg (char **str, struct hash_control *sys_regs,
 	as_warn (_("system register name '%s' is deprecated and may be "
 		   "removed in a future release"), buf);
       value = o->value;
+      if (flags)
+	*flags = o->flags;
     }
 
   *str = q;
@@ -6347,17 +6352,21 @@ parse_operands (char *str, const aarch64_opcode *opcode)
 	  goto regoff_addr;
 
 	case AARCH64_OPND_SYSREG:
-	  if ((val = parse_sys_reg (&str, aarch64_sys_regs_hsh, 1, 0))
-	      == PARSE_FAIL)
-	    {
-	      set_syntax_error (_("unknown or missing system register name"));
-	      goto failure;
-	    }
-	  inst.base.operands[i].sysreg = val;
-	  break;
+	 {
+	   uint32_t sysreg_flags;
+	   if ((val = parse_sys_reg (&str, aarch64_sys_regs_hsh, 1, 0,
+				     &sysreg_flags)) == PARSE_FAIL)
+	     {
+	       set_syntax_error (_("unknown or missing system register name"));
+	       goto failure;
+	     }
+	   inst.base.operands[i].sysreg.value = val;
+	   inst.base.operands[i].sysreg.flags = sysreg_flags;
+	   break;
+	 }
 
 	case AARCH64_OPND_PSTATEFIELD:
-	  if ((val = parse_sys_reg (&str, aarch64_pstatefield_hsh, 0, 1))
+	  if ((val = parse_sys_reg (&str, aarch64_pstatefield_hsh, 0, 1, NULL))
 	      == PARSE_FAIL)
 	    {
 	      set_syntax_error (_("unknown or missing PSTATE field name"));