aarch64: rcpc3: Define address operand fields and inserter/extractors

Beyond the need to encode any registers involved in data transfer and
the address base register for load/stores, it is necessary to specify
the data register addressing mode and whether the address register is
to be pre/post-indexed, whereby loads may be post-indexed and stores
pre-indexed with write-back.

The use of a single bit to specify both the indexing mode and indexing
value requires a novel function be written to accommodate this for
address operand insertion in assembly and another for extraction in
disassembly, along with the definition of two insn fields for use with
these instructions.

This therefore defines the following functions:

  - aarch64_ins_rcpc3_addr_opt_offset
  - aarch64_ins_rcpc3_addr_offset
  - aarch64_ext_rcpc3_addr_opt_offset
  - aarch64_ext_rcpc3_addr_offset

It extends the `do_special_{encoding|decoding}' functions and defines
two rcpc3 instruction fields:

  - FLD_opc2
  - FLD_rcpc3_size

include/opcode/aarch64.h

@@ -1282,7 +1282,9 @@ extern const aarch64_opcode aarch64_opcode_table[];
 #define F_OPD_NARROW (1ULL << 33)
 /* For the instruction with size[22:23] field.  */
 #define F_OPD_SIZE (1ULL << 34)
-/* Next bit is 35.  */
+/* RCPC3 instruction has the field of 'size'.  */
+#define F_RCPC3_SIZE (1ULL << 35)
+/* Next bit is 36.  */
 
 /* Instruction constraints.  */
 /* This instruction has a predication constraint on the instruction at PC+4.  */
@@ -1350,7 +1352,7 @@ opcode_has_special_coder (const aarch64_opcode *opcode)
 {
   return (opcode->flags & (F_SF | F_LSE_SZ | F_SIZEQ | F_FPTYPE | F_SSIZE | F_T
 	  | F_GPRSIZE_IN_Q | F_LDS_SIZE | F_MISC | F_N | F_COND
-	  | F_OPD_SIZE)) != 0;
+	  | F_OPD_SIZE | F_RCPC3_SIZE)) != 0;
 }
 
 struct aarch64_name_value_pair

opcodes/aarch64-asm.c

@@ -702,6 +702,24 @@ aarch64_ins_addr_offset (const aarch64_operand *self ATTRIBUTE_UNUSED,
   return true;
 }
 
+/* Encode the address operand for e.g.
+     stlur <Xt>, [<Xn|SP>{, <amount>}].  */
+bool
+aarch64_ins_rcpc3_addr_offset (const aarch64_operand *self ATTRIBUTE_UNUSED,
+			       const aarch64_opnd_info *info, aarch64_insn *code,
+			       const aarch64_inst *inst ATTRIBUTE_UNUSED,
+			       aarch64_operand_error *errors ATTRIBUTE_UNUSED)
+{
+  /* Rn */
+  insert_field (self->fields[0], code, info->addr.base_regno, 0);
+
+  /* simm9 */
+  int imm = info->addr.offset.imm;
+  insert_field (self->fields[1], code, imm, 0);
+
+  return true;
+}
+
 /* Encode the address operand for e.g. LDRSW <Xt>, [<Xn|SP>, #<simm>]!.  */
 bool
 aarch64_ins_addr_simm (const aarch64_operand *self,
@@ -736,6 +754,28 @@ aarch64_ins_addr_simm (const aarch64_operand *self,
   return true;
 }
 
+/* Encode the address operand, potentially offset by the load/store ammount,
+   e.g. LDIAPP <Xt>, <Xt2> [<Xn|SP>, #<simm>]
+   and  STILP  <Xt>, <Xt2> [<Xn|SP>], #<simm>.*/
+bool
+aarch64_ins_rcpc3_addr_opt_offset (const aarch64_operand *self ATTRIBUTE_UNUSED,
+				   const aarch64_opnd_info *info,
+				   aarch64_insn *code,
+				   const aarch64_inst *inst ATTRIBUTE_UNUSED,
+				   aarch64_operand_error *errors ATTRIBUTE_UNUSED)
+{
+  int imm;
+
+  /* Rn */
+  insert_field (FLD_Rn, code, info->addr.base_regno, 0);
+  /* simm */
+  imm = info->addr.offset.imm;
+  if (!imm)
+    insert_field (FLD_opc2, code, 1, 0);
+
+  return true;
+}
+
 /* Encode the address operand for e.g. LDRAA <Xt>, [<Xn|SP>{, #<simm>}].  */
 bool
 aarch64_ins_addr_simm10 (const aarch64_operand *self,
@@ -1943,6 +1983,22 @@ do_special_encoding (struct aarch64_inst *inst)
 	? 1 : 0;
       insert_field (FLD_lse_sz, &inst->value, value, 0);
     }
+  if (inst->opcode->flags & F_RCPC3_SIZE)
+    {
+      switch (inst->operands[0].qualifier)
+	{
+	case AARCH64_OPND_QLF_W: value = 2; break;
+	case AARCH64_OPND_QLF_X: value = 3; break;
+	case AARCH64_OPND_QLF_S_B: value = 0; break;
+	case AARCH64_OPND_QLF_S_H: value = 1; break;
+	case AARCH64_OPND_QLF_S_S: value = 2; break;
+	case AARCH64_OPND_QLF_S_D: value = 3; break;
+	case AARCH64_OPND_QLF_S_Q: value = 0; break;
+	default: return;
+	}
+      insert_field (FLD_rcpc3_size, &inst->value, value, 0);
+    }
+
   if (inst->opcode->flags & F_SIZEQ)
     encode_sizeq (inst);
   if (inst->opcode->flags & F_FPTYPE)

opcodes/aarch64-asm.h

@@ -115,6 +115,8 @@ AARCH64_DECL_OPD_INSERTER (ins_imm_rotate2);
 AARCH64_DECL_OPD_INSERTER (ins_x0_to_x30);
 AARCH64_DECL_OPD_INSERTER (ins_simple_index);
 AARCH64_DECL_OPD_INSERTER (ins_plain_shrimm);
+AARCH64_DECL_OPD_INSERTER (ins_rcpc3_addr_opt_offset);
+AARCH64_DECL_OPD_INSERTER (ins_rcpc3_addr_offset);
 
 #undef AARCH64_DECL_OPD_INSERTER
 

opcodes/aarch64-dis.c

@@ -1032,6 +1032,70 @@ aarch64_ext_addr_simple (const aarch64_operand *self ATTRIBUTE_UNUSED,
   return true;
 }
 
+/* Decode the address operand for rcpc3 instructions with optional load/store
+   datasize offset, e.g. STILPP <Xs>, <Xt>, [<Xn|SP>{,#-16}]! and
+   LIDAP <Xs>, <Xt>, [<Xn|SP>]{,#-16}.  */
+bool
+aarch64_ext_rcpc3_addr_opt_offset (const aarch64_operand *self ATTRIBUTE_UNUSED,
+				   aarch64_opnd_info *info,
+				   aarch64_insn code,
+				   const aarch64_inst *inst ATTRIBUTE_UNUSED,
+				   aarch64_operand_error *err ATTRIBUTE_UNUSED)
+{
+  info->addr.base_regno = extract_field (FLD_Rn, code, 0);
+  if (!extract_field (FLD_opc2, code, 0))
+    {
+      info->addr.writeback = 1;
+
+      enum aarch64_opnd type;
+      for (int i = 0; i < AARCH64_MAX_OPND_NUM; i++)
+	{
+	  aarch64_opnd_info opnd = info[i];
+	  type = opnd.type;
+	  if (aarch64_operands[type].op_class == AARCH64_OPND_CLASS_ADDRESS)
+	    break;
+	}
+
+      assert (aarch64_operands[type].op_class == AARCH64_OPND_CLASS_ADDRESS);
+      int offset = calc_ldst_datasize (inst->operands);
+
+      switch (type)
+	{
+	case AARCH64_OPND_RCPC3_ADDR_OPT_PREIND_WB:
+	case AARCH64_OPND_RCPC3_ADDR_PREIND_WB:
+	  info->addr.offset.imm = -offset;
+	  info->addr.preind = 1;
+	  break;
+	case AARCH64_OPND_RCPC3_ADDR_OPT_POSTIND:
+	case AARCH64_OPND_RCPC3_ADDR_POSTIND:
+	  info->addr.offset.imm = offset;
+	  info->addr.postind = 1;
+	  break;
+	default:
+	  return false;
+	}
+    }
+  return true;
+}
+
+bool
+aarch64_ext_rcpc3_addr_offset (const aarch64_operand *self ATTRIBUTE_UNUSED,
+			       aarch64_opnd_info *info,
+			       aarch64_insn code,
+			       const aarch64_inst *inst ATTRIBUTE_UNUSED,
+			       aarch64_operand_error *errors ATTRIBUTE_UNUSED)
+{
+  info->qualifier = get_expected_qualifier (inst, info->idx);
+
+  /* Rn */
+  info->addr.base_regno = extract_field (self->fields[0], code, 0);
+
+  /* simm9 */
+  aarch64_insn imm = extract_fields (code, 0, 1, self->fields[1]);
+  info->addr.offset.imm = sign_extend (imm, 8);
+  return true;
+}
+
 /* Decode the address operand for e.g.
      stlur <Xt>, [<Xn|SP>{, <amount>}].  */
 bool
@@ -2579,6 +2643,26 @@ do_special_decoding (aarch64_inst *inst)
       value = extract_field (FLD_lse_sz, inst->value, 0);
       inst->operands[idx].qualifier = get_greg_qualifier_from_value (value);
     }
+  /* rcpc3 'size' field.  */
+  if (inst->opcode->flags & F_RCPC3_SIZE)
+    {
+      value = extract_field (FLD_rcpc3_size, inst->value, 0);
+      for (int i = 0;
+	   aarch64_operands[inst->operands[i].type].op_class != AARCH64_OPND_CLASS_ADDRESS;
+	   i++)
+	{
+	  if (aarch64_operands[inst->operands[i].type].op_class
+	      == AARCH64_OPND_CLASS_INT_REG)
+	    inst->operands[i].qualifier = get_greg_qualifier_from_value (value & 1);
+	  else if (aarch64_operands[inst->operands[i].type].op_class
+	      == AARCH64_OPND_CLASS_FP_REG)
+	    {
+	      value += (extract_field (FLD_opc1, inst->value, 0) << 2);
+	      inst->operands[i].qualifier = get_sreg_qualifier_from_value (value);
+	    }
+	}
+    }
+
   /* size:Q fields.  */
   if (inst->opcode->flags & F_SIZEQ)
     return decode_sizeq (inst);

opcodes/aarch64-dis.h

@@ -140,6 +140,9 @@ AARCH64_DECL_OPD_EXTRACTOR (ext_x0_to_x30);
 AARCH64_DECL_OPD_EXTRACTOR (ext_simple_index);
 AARCH64_DECL_OPD_EXTRACTOR (ext_plain_shrimm);
 AARCH64_DECL_OPD_EXTRACTOR (ext_sve_reglist_zt);
+AARCH64_DECL_OPD_EXTRACTOR (ext_rcpc3_addr_opt_offset);
+AARCH64_DECL_OPD_EXTRACTOR (ext_rcpc3_addr_offset);
+
 
 #undef AARCH64_DECL_OPD_EXTRACTOR
 

opcodes/aarch64-opc.c

@@ -410,6 +410,8 @@ const aarch64_field fields[] =
     {  6,  2 }, /* ZAn_2: name of the 2bit encoded ZA tile.  */
     {  5,  3 }, /* ZAn_3: name of the 3bit encoded ZA tile.  */
     {  6,  1 }, /* ZAn: name of the bit encoded ZA tile.  */
+    { 12,  4 },	/* opc2: in rcpc3 ld/st inst deciding the pre/post-index.  */
+    { 30,  2 },	/* rcpc3_size: in rcpc3 ld/st, field controls Rt/Rt2 width.  */
 };
 
 enum aarch64_operand_class

opcodes/aarch64-opc.h

@@ -216,7 +216,9 @@ enum aarch64_field_kind
   FLD_ol,
   FLD_ZAn_2,
   FLD_ZAn_3,
-  FLD_ZAn
+  FLD_ZAn,
+  FLD_opc2,
+  FLD_rcpc3_size,
 };
 
 /* Field description.  */