/* Capstone Disassembly Engine */
/* By billow <billow.fun@gmail.com>, 2024 */

#include <capstone/xtensa.h>

#include "../../MCRegisterInfo.h"
#include "../../MCInst.h"
#include "../../SStream.h"
#include "../../Mapping.h"
#include "../../utils.h"
#include "../../cs_simple_types.h"
#include "XtensaDisassembler.h"
#include "XtensaInstPrinter.h"
#include "priv.h"
#include "XtensaMapping.h"

#ifndef CAPSTONE_DIET

static const char *const insn_name_maps[] = {
#include "XtensaGenCSMappingInsnName.inc"
};

static const name_map group_name_maps[] = {
#include "XtensaGenCSFeatureName.inc"
};

const insn_map mapping_insns[] = {
#include "XtensaGenCSMappingInsn.inc"
};

static const map_insn_ops insn_operands[] = {
#include "XtensaGenCSMappingInsnOp.inc"
};

#endif

#define GET_REGINFO_MC_DESC
#include "XtensaGenRegisterInfo.inc"
#include "../../MathExtras.h"

void Xtensa_init_mri(MCRegisterInfo *mri)
{
	MCRegisterInfo_InitMCRegisterInfo(
		mri, XtensaRegDesc, ARR_SIZE(XtensaRegDesc), 0, 0,
		XtensaMCRegisterClasses, ARR_SIZE(XtensaMCRegisterClasses), 0,
		0, XtensaRegDiffLists, NULL, XtensaSubRegIdxLists,
		ARR_SIZE(XtensaSubRegIdxLists), XtensaRegEncodingTable);
}

void Xtensa_printer(MCInst *MI, SStream *OS, void *info)
{
	Xtensa_LLVM_printInstruction(MI, MI->address, OS);
}

static void set_instr_map_data(MCInst *MI)
{
#ifndef CAPSTONE_DIET
	map_cs_id(MI, mapping_insns, ARR_SIZE(mapping_insns));
	map_implicit_reads(MI, mapping_insns);
	map_implicit_writes(MI, mapping_insns);
	map_groups(MI, mapping_insns);
#endif
}

bool Xtensa_disasm(csh handle, const uint8_t *code, size_t code_len,
		   MCInst *instr, uint16_t *size, uint64_t address, void *info)
{
	DecodeStatus res = Xtensa_LLVM_getInstruction(instr, size, code,
						      code_len, address);
	if (res == MCDisassembler_Success) {
		set_instr_map_data(instr);
	}
	return res == MCDisassembler_Success;
}

const char *Xtensa_reg_name(csh handle, unsigned int id)
{
	return Xtensa_LLVM_getRegisterName(id);
}

void Xtensa_insn_id(cs_struct *h, cs_insn *insn, unsigned int id)
{
	// Done in Xtensa_disasm
}

const char *Xtensa_insn_name(csh handle, unsigned int id)
{
#ifndef CAPSTONE_DIET
	if (id >= ARR_SIZE(insn_name_maps)) {
		return NULL;
	}
	return insn_name_maps[id];
#else
	return NULL;
#endif
}

const char *Xtensa_group_name(csh handle, unsigned int id)
{
#ifndef CAPSTONE_DIET
	return id2name(group_name_maps, ARR_SIZE(group_name_maps), id);
#else
	return NULL;
#endif
}

#ifndef CAPSTONE_DIET
void Xtensa_reg_access(const cs_insn *insn, cs_regs regs_read,
		       uint8_t *regs_read_count, cs_regs regs_write,
		       uint8_t *regs_write_count)
{
	uint8_t i;
	uint8_t read_count, write_count;
	cs_xtensa *detail = &(insn->detail->xtensa);

	read_count = insn->detail->regs_read_count;
	write_count = insn->detail->regs_write_count;

	// implicit registers
	memcpy(regs_read, insn->detail->regs_read,
	       read_count * sizeof(insn->detail->regs_read[0]));
	memcpy(regs_write, insn->detail->regs_write,
	       write_count * sizeof(insn->detail->regs_write[0]));

	// explicit registers
	for (i = 0; i < detail->op_count; i++) {
		cs_xtensa_op *op = &(detail->operands[i]);
		switch (op->type) {
		case XTENSA_OP_REG:
			if ((op->access & CS_AC_READ) &&
			    !arr_exist(regs_read, read_count, op->reg)) {
				regs_read[read_count] = (uint16_t)op->reg;
				read_count++;
			}
			if ((op->access & CS_AC_WRITE) &&
			    !arr_exist(regs_write, write_count, op->reg)) {
				regs_write[write_count] = (uint16_t)op->reg;
				write_count++;
			}
			break;
		case XTENSA_OP_MEM:
			// registers appeared in memory references always being read
			if ((op->mem.base != XTENSA_REG_INVALID) &&
			    !arr_exist(regs_read, read_count, op->mem.base)) {
				regs_read[read_count] = (uint16_t)op->mem.base;
				read_count++;
			}
			if ((insn->detail->writeback) &&
			    (op->mem.base != XTENSA_REG_INVALID) &&
			    !arr_exist(regs_write, write_count, op->mem.base)) {
				regs_write[write_count] =
					(uint16_t)op->mem.base;
				write_count++;
			}
		default:
			break;
		}
	}

	*regs_read_count = read_count;
	*regs_write_count = write_count;
}
#endif

void Xtensa_add_cs_detail(MCInst *MI, xtensa_op_group op_group, va_list args)
{
	int op_num = va_arg(args, int);
	cs_xtensa_op *xop = Xtensa_get_detail_op(MI, 0);
	switch (op_group) {
	case XTENSA_OP_GROUP_OPERAND: {
		const MCOperand *MC = MCInst_getOperand(MI, op_num);
		if (MCOperand_isReg(MC)) {
			xop->type = XTENSA_OP_REG;
			xop->reg = MC->RegVal;
		} else if (MCOperand_isImm(MC)) {
			xop->type = XTENSA_OP_IMM;
			xop->imm = MC->ImmVal;
		}
	} break;
	case XTENSA_OP_GROUP_IMM8_ASMOPERAND:
	case XTENSA_OP_GROUP_IMM8_SH8_ASMOPERAND:
	case XTENSA_OP_GROUP_UIMM5_ASMOPERAND:
	case XTENSA_OP_GROUP_B4CONST_ASMOPERAND:
	case XTENSA_OP_GROUP_B4CONSTU_ASMOPERAND:
	case XTENSA_OP_GROUP_IMM1_16_ASMOPERAND:
	case XTENSA_OP_GROUP_IMM12M_ASMOPERAND:
	case XTENSA_OP_GROUP_SHIMM1_31_ASMOPERAND:
	case XTENSA_OP_GROUP_UIMM4_ASMOPERAND: {
		int64_t val = MCOperand_getImm(MCInst_getOperand(MI, op_num));
		xop->type = XTENSA_OP_IMM;
		xop->imm = (int32_t)val;
	} break;
	case XTENSA_OP_GROUP_BRANCHTARGET:
	case XTENSA_OP_GROUP_JUMPTARGET:
	case XTENSA_OP_GROUP_CALLOPERAND: {
		int64_t val =
			MCOperand_getImm(MCInst_getOperand(MI, op_num)) + 4;
		xop->type = XTENSA_OP_IMM;
		xop->imm = (int32_t)val;
	} break;
	case XTENSA_OP_GROUP_L32RTARGET: {
		int64_t Value =
			MCOperand_getImm(MCInst_getOperand(MI, (op_num)));
		int32_t InstrOff = (uint32_t)OneExtend32(Value, 16) << 2;
		CS_ASSERT(
			(InstrOff >= -262144 && InstrOff <= -4) &&
			"Invalid argument, value must be in ranges [-262144,-4]");
		if (MI->csh->LITBASE & 0x1) {
			Value = ((MI->csh->LITBASE & 0xfffff000) >> 12) + InstrOff;
		} else {
			Value = (((int64_t)MI->address + 3) & ~0x3) + InstrOff;
		}
		xop->type = XTENSA_OP_L32R;
		xop->imm = (int32_t)Value;
	} break;
	case XTENSA_OP_GROUP_MEMOPERAND: {
		unsigned reg =
			MCOperand_getReg(MCInst_getOperand(MI, (op_num)));
		int64_t imm8 =
			MCOperand_getImm(MCInst_getOperand(MI, op_num + 1));
		xop->type = XTENSA_OP_MEM;
		xop->mem.base = reg;
		xop->mem.disp = (uint8_t)imm8;
	} break;
	}

	xop->access = map_get_op_access(MI, op_num);
	Xtensa_inc_op_count(MI);
}