/*
 *  SH4 emulation
 *
 *  Copyright (c) 2005 Samuel Tardieu
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 */
#include "qemu/osdep.h"
#include "cpu.h"
#include "exec/helper-proto.h"
#include "exec/exec-all.h"
#include "exec/cpu_ldst.h"
#include "fpu/softfloat.h"

#ifndef CONFIG_USER_ONLY

void superh_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
                                    MMUAccessType access_type,
                                    int mmu_idx, uintptr_t retaddr)
{
    cpu_env(cs)->tea = addr;
    switch (access_type) {
    case MMU_INST_FETCH:
    case MMU_DATA_LOAD:
        cs->exception_index = 0x0e0;
        break;
    case MMU_DATA_STORE:
        cs->exception_index = 0x100;
        break;
    default:
        g_assert_not_reached();
    }
    cpu_loop_exit_restore(cs, retaddr);
}

#endif

void helper_ldtlb(CPUSH4State *env)
{
#ifdef CONFIG_USER_ONLY
    cpu_abort(env_cpu(env), "Unhandled ldtlb");
#else
    cpu_load_tlb(env);
#endif
}

static inline G_NORETURN
void raise_exception(CPUSH4State *env, int index,
                     uintptr_t retaddr)
{
    CPUState *cs = env_cpu(env);

    cs->exception_index = index;
    cpu_loop_exit_restore(cs, retaddr);
}

void helper_raise_illegal_instruction(CPUSH4State *env)
{
    raise_exception(env, 0x180, 0);
}

void helper_raise_slot_illegal_instruction(CPUSH4State *env)
{
    raise_exception(env, 0x1a0, 0);
}

void helper_raise_fpu_disable(CPUSH4State *env)
{
    raise_exception(env, 0x800, 0);
}

void helper_raise_slot_fpu_disable(CPUSH4State *env)
{
    raise_exception(env, 0x820, 0);
}

void helper_sleep(CPUSH4State *env)
{
    CPUState *cs = env_cpu(env);

    cs->halted = 1;
    env->in_sleep = 1;
    raise_exception(env, EXCP_HLT, 0);
}

void helper_trapa(CPUSH4State *env, uint32_t tra)
{
    env->tra = tra << 2;
    raise_exception(env, 0x160, 0);
}

void helper_exclusive(CPUSH4State *env)
{
    /* We do not want cpu_restore_state to run.  */
    cpu_loop_exit_atomic(env_cpu(env), 0);
}

void helper_movcal(CPUSH4State *env, uint32_t address, uint32_t value)
{
    if (cpu_sh4_is_cached (env, address))
    {
        memory_content *r = g_new(memory_content, 1);

        r->address = address;
        r->value = value;
        r->next = NULL;

        *(env->movcal_backup_tail) = r;
        env->movcal_backup_tail = &(r->next);
    }
}

void helper_discard_movcal_backup(CPUSH4State *env)
{
    memory_content *current = env->movcal_backup;

    while(current)
    {
        memory_content *next = current->next;
        g_free(current);
        env->movcal_backup = current = next;
        if (current == NULL)
            env->movcal_backup_tail = &(env->movcal_backup);
    }
}

void helper_ocbi(CPUSH4State *env, uint32_t address)
{
    memory_content **current = &(env->movcal_backup);
    while (*current)
    {
        uint32_t a = (*current)->address;
        if ((a & ~0x1F) == (address & ~0x1F))
        {
            memory_content *next = (*current)->next;
            cpu_stl_data(env, a, (*current)->value);

            if (next == NULL)
            {
                env->movcal_backup_tail = current;
            }

            g_free(*current);
            *current = next;
            break;
        }
    }
}

void helper_macl(CPUSH4State *env, int32_t arg0, int32_t arg1)
{
    const int64_t min = -(1ll << 47);
    const int64_t max = (1ll << 47) - 1;
    int64_t mul = (int64_t)arg0 * arg1;
    int64_t mac = env->mac;
    int64_t res;

    if (!(env->sr & (1u << SR_S))) {
        res = mac + mul;
    } else if (sadd64_overflow(mac, mul, &res)) {
        res = mac < 0 ? min : max;
    } else {
        res = MIN(MAX(res, min), max);
    }

    env->mac = res;
}

void helper_macw(CPUSH4State *env, int32_t arg0, int32_t arg1)
{
    /* Inputs are already sign-extended from 16 bits. */
    int32_t mul = arg0 * arg1;

    if (env->sr & (1u << SR_S)) {
        /*
         * In saturation arithmetic mode, the accumulator is 32-bit
         * with carry. MACH is not considered during the addition
         * operation nor the 32-bit saturation logic.
         */
        int32_t res, macl = env->macl;

        if (sadd32_overflow(macl, mul, &res)) {
            res = macl < 0 ? INT32_MIN : INT32_MAX;
            /* If overflow occurs, the MACH register is set to 1. */
            env->mach = 1;
        }
        env->macl = res;
    } else {
        /* In non-saturation arithmetic mode, the accumulator is 64-bit */
        env->mac += mul;
    }
}

void helper_ld_fpscr(CPUSH4State *env, uint32_t val)
{
    env->fpscr = val & FPSCR_MASK;
    if ((val & FPSCR_RM_MASK) == FPSCR_RM_ZERO) {
        set_float_rounding_mode(float_round_to_zero, &env->fp_status);
    } else {
        set_float_rounding_mode(float_round_nearest_even, &env->fp_status);
    }
    set_flush_to_zero((val & FPSCR_DN) != 0, &env->fp_status);
}

static void update_fpscr(CPUSH4State *env, uintptr_t retaddr)
{
    int xcpt, cause, enable;

    xcpt = get_float_exception_flags(&env->fp_status);

    /* Clear the cause entries */
    env->fpscr &= ~FPSCR_CAUSE_MASK;

    if (unlikely(xcpt)) {
        if (xcpt & float_flag_invalid) {
            env->fpscr |= FPSCR_CAUSE_V;
        }
        if (xcpt & float_flag_divbyzero) {
            env->fpscr |= FPSCR_CAUSE_Z;
        }
        if (xcpt & float_flag_overflow) {
            env->fpscr |= FPSCR_CAUSE_O;
        }
        if (xcpt & float_flag_underflow) {
            env->fpscr |= FPSCR_CAUSE_U;
        }
        if (xcpt & float_flag_inexact) {
            env->fpscr |= FPSCR_CAUSE_I;
        }

        /* Accumulate in flag entries */
        env->fpscr |= (env->fpscr & FPSCR_CAUSE_MASK)
                      >> (FPSCR_CAUSE_SHIFT - FPSCR_FLAG_SHIFT);

        /* Generate an exception if enabled */
        cause = (env->fpscr & FPSCR_CAUSE_MASK) >> FPSCR_CAUSE_SHIFT;
        enable = (env->fpscr & FPSCR_ENABLE_MASK) >> FPSCR_ENABLE_SHIFT;
        if (cause & enable) {
            raise_exception(env, 0x120, retaddr);
        }
    }
}

float32 helper_fadd_FT(CPUSH4State *env, float32 t0, float32 t1)
{
    set_float_exception_flags(0, &env->fp_status);
    t0 = float32_add(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return t0;
}

float64 helper_fadd_DT(CPUSH4State *env, float64 t0, float64 t1)
{
    set_float_exception_flags(0, &env->fp_status);
    t0 = float64_add(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return t0;
}

uint32_t helper_fcmp_eq_FT(CPUSH4State *env, float32 t0, float32 t1)
{
    int relation;

    set_float_exception_flags(0, &env->fp_status);
    relation = float32_compare(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return relation == float_relation_equal;
}

uint32_t helper_fcmp_eq_DT(CPUSH4State *env, float64 t0, float64 t1)
{
    int relation;

    set_float_exception_flags(0, &env->fp_status);
    relation = float64_compare(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return relation == float_relation_equal;
}

uint32_t helper_fcmp_gt_FT(CPUSH4State *env, float32 t0, float32 t1)
{
    int relation;

    set_float_exception_flags(0, &env->fp_status);
    relation = float32_compare(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return relation == float_relation_greater;
}

uint32_t helper_fcmp_gt_DT(CPUSH4State *env, float64 t0, float64 t1)
{
    int relation;

    set_float_exception_flags(0, &env->fp_status);
    relation = float64_compare(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return relation == float_relation_greater;
}

float64 helper_fcnvsd_FT_DT(CPUSH4State *env, float32 t0)
{
    float64 ret;
    set_float_exception_flags(0, &env->fp_status);
    ret = float32_to_float64(t0, &env->fp_status);
    update_fpscr(env, GETPC());
    return ret;
}

float32 helper_fcnvds_DT_FT(CPUSH4State *env, float64 t0)
{
    float32 ret;
    set_float_exception_flags(0, &env->fp_status);
    ret = float64_to_float32(t0, &env->fp_status);
    update_fpscr(env, GETPC());
    return ret;
}

float32 helper_fdiv_FT(CPUSH4State *env, float32 t0, float32 t1)
{
    set_float_exception_flags(0, &env->fp_status);
    t0 = float32_div(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return t0;
}

float64 helper_fdiv_DT(CPUSH4State *env, float64 t0, float64 t1)
{
    set_float_exception_flags(0, &env->fp_status);
    t0 = float64_div(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return t0;
}

float32 helper_float_FT(CPUSH4State *env, uint32_t t0)
{
    float32 ret;
    set_float_exception_flags(0, &env->fp_status);
    ret = int32_to_float32(t0, &env->fp_status);
    update_fpscr(env, GETPC());
    return ret;
}

float64 helper_float_DT(CPUSH4State *env, uint32_t t0)
{
    float64 ret;
    set_float_exception_flags(0, &env->fp_status);
    ret = int32_to_float64(t0, &env->fp_status);
    update_fpscr(env, GETPC());
    return ret;
}

float32 helper_fmac_FT(CPUSH4State *env, float32 t0, float32 t1, float32 t2)
{
    set_float_exception_flags(0, &env->fp_status);
    t0 = float32_muladd(t0, t1, t2, 0, &env->fp_status);
    update_fpscr(env, GETPC());
    return t0;
}

float32 helper_fmul_FT(CPUSH4State *env, float32 t0, float32 t1)
{
    set_float_exception_flags(0, &env->fp_status);
    t0 = float32_mul(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return t0;
}

float64 helper_fmul_DT(CPUSH4State *env, float64 t0, float64 t1)
{
    set_float_exception_flags(0, &env->fp_status);
    t0 = float64_mul(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return t0;
}

float32 helper_fsqrt_FT(CPUSH4State *env, float32 t0)
{
    set_float_exception_flags(0, &env->fp_status);
    t0 = float32_sqrt(t0, &env->fp_status);
    update_fpscr(env, GETPC());
    return t0;
}

float64 helper_fsqrt_DT(CPUSH4State *env, float64 t0)
{
    set_float_exception_flags(0, &env->fp_status);
    t0 = float64_sqrt(t0, &env->fp_status);
    update_fpscr(env, GETPC());
    return t0;
}

float32 helper_fsrra_FT(CPUSH4State *env, float32 t0)
{
    set_float_exception_flags(0, &env->fp_status);
    /* "Approximate" 1/sqrt(x) via actual computation.  */
    t0 = float32_sqrt(t0, &env->fp_status);
    t0 = float32_div(float32_one, t0, &env->fp_status);
    /*
     * Since this is supposed to be an approximation, an imprecision
     * exception is required.  One supposes this also follows the usual
     * IEEE rule that other exceptions take precedence.
     */
    if (get_float_exception_flags(&env->fp_status) == 0) {
        set_float_exception_flags(float_flag_inexact, &env->fp_status);
    }
    update_fpscr(env, GETPC());
    return t0;
}

float32 helper_fsub_FT(CPUSH4State *env, float32 t0, float32 t1)
{
    set_float_exception_flags(0, &env->fp_status);
    t0 = float32_sub(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return t0;
}

float64 helper_fsub_DT(CPUSH4State *env, float64 t0, float64 t1)
{
    set_float_exception_flags(0, &env->fp_status);
    t0 = float64_sub(t0, t1, &env->fp_status);
    update_fpscr(env, GETPC());
    return t0;
}

uint32_t helper_ftrc_FT(CPUSH4State *env, float32 t0)
{
    uint32_t ret;
    set_float_exception_flags(0, &env->fp_status);
    ret = float32_to_int32_round_to_zero(t0, &env->fp_status);
    update_fpscr(env, GETPC());
    return ret;
}

uint32_t helper_ftrc_DT(CPUSH4State *env, float64 t0)
{
    uint32_t ret;
    set_float_exception_flags(0, &env->fp_status);
    ret = float64_to_int32_round_to_zero(t0, &env->fp_status);
    update_fpscr(env, GETPC());
    return ret;
}

void helper_fipr(CPUSH4State *env, uint32_t m, uint32_t n)
{
    int bank, i;
    float32 r, p;

    bank = (env->sr & FPSCR_FR) ? 16 : 0;
    r = float32_zero;
    set_float_exception_flags(0, &env->fp_status);

    for (i = 0 ; i < 4 ; i++) {
        p = float32_mul(env->fregs[bank + m + i],
                        env->fregs[bank + n + i],
                        &env->fp_status);
        r = float32_add(r, p, &env->fp_status);
    }
    update_fpscr(env, GETPC());

    env->fregs[bank + n + 3] = r;
}

void helper_ftrv(CPUSH4State *env, uint32_t n)
{
    int bank_matrix, bank_vector;
    int i, j;
    float32 r[4];
    float32 p;

    bank_matrix = (env->sr & FPSCR_FR) ? 0 : 16;
    bank_vector = (env->sr & FPSCR_FR) ? 16 : 0;
    set_float_exception_flags(0, &env->fp_status);
    for (i = 0 ; i < 4 ; i++) {
        r[i] = float32_zero;
        for (j = 0 ; j < 4 ; j++) {
            p = float32_mul(env->fregs[bank_matrix + 4 * j + i],
                            env->fregs[bank_vector + j],
                            &env->fp_status);
            r[i] = float32_add(r[i], p, &env->fp_status);
        }
    }
    update_fpscr(env, GETPC());

    for (i = 0 ; i < 4 ; i++) {
        env->fregs[bank_vector + i] = r[i];
    }
}