/* Unicorn Emulator Engine */
/* By Nguyen Anh Quynh <aquynh@gmail.com>, 2015 */

#include <string.h>

#include "qemu/osdep.h"
#include "cpu.h"
#include "hw/boards.h"
#include "hw/riscv/spike.h"
#include "sysemu/cpus.h"
#include "unicorn.h"
#include "unicorn_common.h"
#include "uc_priv.h"

#ifdef TARGET_RISCV32
const int RISCV32_REGS_STORAGE_SIZE = offsetof(CPURISCVState, tlb_table);
#else
const int RISCV64_REGS_STORAGE_SIZE = offsetof(CPURISCVState, tlb_table);
#endif

static void riscv_release(void *ctx) {
    TCGContext *tcg_ctx = (TCGContext *) ctx;

    release_common(ctx);
    g_free(tcg_ctx->tb_ctx.tbs);
}

static void riscv_reg_reset(struct uc_struct *uc) {
    CPUArchState *env = uc->cpu->env_ptr;

    memset(env->gpr, 0, sizeof(env->gpr));
    memset(env->fpr, 0, sizeof(env->fpr));

    env->priv = PRV_M;
    env->mstatus &= ~(MSTATUS_MIE | MSTATUS_MPRV);
    env->mcause = 0;
    env->pc = env->resetvec;

    set_default_nan_mode(1, &env->fp_status);
}

static int riscv_reg_read(struct uc_struct *uc, unsigned int *regs, void **vals, int count) {
    CPUState *const cs = uc->cpu;
    CPURISCVState *const state = &RISCV_CPU(uc, cs)->env;

    for (int i = 0; i < count; i++) {
        const unsigned int reg_id = regs[i];
        void *const value = vals[i];

        if (reg_id >= UC_RISCV_REG_X0 && reg_id <= UC_RISCV_REG_X31) {
            memcpy(value, &state->gpr[reg_id - UC_RISCV_REG_X0], sizeof(state->gpr[0]));
        } else if (reg_id >= UC_RISCV_REG_F0 && reg_id <= UC_RISCV_REG_F31) {
            memcpy(value, &state->fpr[reg_id - UC_RISCV_REG_F0], sizeof(state->fpr[0]));
        } else if (reg_id == UC_RISCV_REG_PC) {
            memcpy(value, &state->pc, sizeof(state->pc));
        }
    }

    return 0;
}

static int riscv_reg_write(struct uc_struct *uc, unsigned int *regs, void *const *vals, int count) {
    CPUState *const cs = uc->cpu;
    CPURISCVState *const state = &RISCV_CPU(uc, cs)->env;

    for (int i = 0; i < count; i++) {
        const unsigned int reg_id = regs[i];
        const void *value = vals[i];

        // Intentionally exclude the zero register (X0) in the lower-bound
        if (reg_id > UC_RISCV_REG_X0 && reg_id <= UC_RISCV_REG_X31) {
            memcpy(&state->gpr[reg_id - UC_RISCV_REG_X0], value, sizeof(state->gpr[0]));
        } else if (reg_id >= UC_RISCV_REG_F0 && reg_id <= UC_RISCV_REG_F31) {
            memcpy(&state->fpr[reg_id - UC_RISCV_REG_F0], value, sizeof(state->fpr[0]));
        } else if (reg_id == UC_RISCV_REG_PC) {
            memcpy(&state->pc, value, sizeof(state->pc));
            // force to quit execution and flush TB
            uc->quit_request = true;
            uc_emu_stop(uc);
        }
    }

    return 0;
}

static void riscv_set_pc(struct uc_struct *uc, uint64_t address) {
    CPURISCVState *state = uc->cpu->env_ptr;

    state->pc = address;
}

static bool riscv_stop_interrupt(int int_no) {
    switch(int_no) {
    default:
        return false;
    }
}

DEFAULT_VISIBILITY
#ifdef TARGET_RISCV32
void riscv32_uc_init(struct uc_struct *uc) {
#else
void riscv64_uc_init(struct uc_struct *uc) {
#endif
    register_accel_types(uc);
    riscv_cpu_register_types(uc);
    spike_v1_10_0_machine_init_register_types(uc);

    uc->release = riscv_release;
    uc->reg_read = riscv_reg_read;
    uc->reg_write = riscv_reg_write;
    uc->reg_reset = riscv_reg_reset;
    uc->set_pc = riscv_set_pc;
    uc->stop_interrupt = riscv_stop_interrupt;

    uc_common_init(uc);
}