tcg.c

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    int idx;

    idx = s->nb_temps;
#if TCG_TARGET_REG_BITS == 32
    tcg_temp_alloc(s, idx + 2);
    ts = &s->temps[idx];
    ts->base_type = TCG_TYPE_I64;
    ts->type = TCG_TYPE_I32;
    ts->val_type = TEMP_VAL_CONST;
    ts->name = NULL;
    ts->val = val;
    ts++;
    ts->base_type = TCG_TYPE_I32;
    ts->type = TCG_TYPE_I32;
    ts->val_type = TEMP_VAL_CONST;
    ts->name = NULL;
    ts->val = val >> 32;
    s->nb_temps += 2;
#else
    tcg_temp_alloc(s, idx + 1);
    ts = &s->temps[idx];
    ts->base_type = ts->type = TCG_TYPE_I64;
    ts->val_type = TEMP_VAL_CONST;
    ts->name = NULL;
    ts->val = val;
    s->nb_temps++;
#endif    
    return MAKE_TCGV(idx);
}

void tcg_register_helper(void *func, const char *name)
{
    TCGContext *s = &tcg_ctx;
    int n;
    if ((s->nb_helpers + 1) > s->allocated_helpers) {
        n = s->allocated_helpers;
        if (n == 0) {
            n = 4;
        } else {
            n *= 2;
        }
        s->helpers = realloc(s->helpers, n * sizeof(TCGHelperInfo));
        s->allocated_helpers = n;
    }
    s->helpers[s->nb_helpers].func = func;
    s->helpers[s->nb_helpers].name = name;
    s->nb_helpers++;
}

const char *tcg_helper_get_name(TCGContext *s, void *func)
{
    int i;

    for(i = 0; i < s->nb_helpers; i++) {
        if (s->helpers[i].func == func)
            return s->helpers[i].name;
    }
    return NULL;
}

static inline TCGType tcg_get_base_type(TCGContext *s, TCGv arg)
{
    return s->temps[GET_TCGV(arg)].base_type;
}

static void tcg_gen_call_internal(TCGContext *s, TCGv func, 
                                  unsigned int flags,
                                  unsigned int nb_rets, const TCGv *rets,
                                  unsigned int nb_params, const TCGv *params)
{
    int i;
    *gen_opc_ptr++ = INDEX_op_call;
    *gen_opparam_ptr++ = (nb_rets << 16) | (nb_params + 1);
    for(i = 0; i < nb_rets; i++) {
        *gen_opparam_ptr++ = GET_TCGV(rets[i]);
    }
    for(i = 0; i < nb_params; i++) {
        *gen_opparam_ptr++ = GET_TCGV(params[i]);
    }
    *gen_opparam_ptr++ = GET_TCGV(func);

    *gen_opparam_ptr++ = flags;
    /* total parameters, needed to go backward in the instruction stream */
    *gen_opparam_ptr++ = 1 + nb_rets + nb_params + 3;
}


#if TCG_TARGET_REG_BITS < 64
/* Note: we convert the 64 bit args to 32 bit */
void tcg_gen_call(TCGContext *s, TCGv func, unsigned int flags,
                  unsigned int nb_rets, const TCGv *rets,
                  unsigned int nb_params, const TCGv *args1)
{
    TCGv ret, *args2, rets_2[2], arg;
    int j, i, call_type;

    if (nb_rets == 1) {
        ret = rets[0];
        if (tcg_get_base_type(s, ret) == TCG_TYPE_I64) {
            nb_rets = 2;
            rets_2[0] = ret;
            rets_2[1] = TCGV_HIGH(ret);
            rets = rets_2;
        }
    }
    args2 = alloca((nb_params * 2) * sizeof(TCGv));
    j = 0;
    call_type = (flags & TCG_CALL_TYPE_MASK);
    for(i = 0; i < nb_params; i++) {
        arg = args1[i];
        if (tcg_get_base_type(s, arg) == TCG_TYPE_I64) {
#ifdef TCG_TARGET_I386
            /* REGPARM case: if the third parameter is 64 bit, it is
               allocated on the stack */
            if (j == 2 && call_type == TCG_CALL_TYPE_REGPARM) {
                call_type = TCG_CALL_TYPE_REGPARM_2;
                flags = (flags & ~TCG_CALL_TYPE_MASK) | call_type;
            }
            args2[j++] = arg;
            args2[j++] = TCGV_HIGH(arg);
#else
#ifdef TCG_TARGET_WORDS_BIGENDIAN
            args2[j++] = TCGV_HIGH(arg);
            args2[j++] = arg;
#else
            args2[j++] = arg;
            args2[j++] = TCGV_HIGH(arg);
#endif
#endif
        } else {
            args2[j++] = arg;
        }
    }
    tcg_gen_call_internal(s, func, flags, 
                          nb_rets, rets, j, args2);
}
#else
void tcg_gen_call(TCGContext *s, TCGv func, unsigned int flags,
                  unsigned int nb_rets, const TCGv *rets,
                  unsigned int nb_params, const TCGv *args1)
{
    tcg_gen_call_internal(s, func, flags, 
                          nb_rets, rets, nb_params, args1);
}
#endif

#if TCG_TARGET_REG_BITS == 32
void tcg_gen_shifti_i64(TCGv ret, TCGv arg1, 
                        int c, int right, int arith)
{
    if (c == 0)
        return;
    if (c >= 32) {
        c -= 32;
        if (right) {
            if (arith) {
                tcg_gen_sari_i32(ret, TCGV_HIGH(arg1), c);
                tcg_gen_sari_i32(TCGV_HIGH(ret), TCGV_HIGH(arg1), 31);
            } else {
                tcg_gen_shri_i32(ret, TCGV_HIGH(arg1), c);
                tcg_gen_movi_i32(TCGV_HIGH(ret), 0);
            }
        } else {
            tcg_gen_shli_i32(TCGV_HIGH(ret), arg1, c);
            tcg_gen_movi_i32(ret, 0);
        }
    } else {
        TCGv t0, t1;

        t0 = tcg_temp_new(TCG_TYPE_I32);
        t1 = tcg_temp_new(TCG_TYPE_I32);
        if (right) {
            tcg_gen_shli_i32(t0, TCGV_HIGH(arg1), 32 - c);
            if (arith)
                tcg_gen_sari_i32(t1, TCGV_HIGH(arg1), c);
            else 
                tcg_gen_shri_i32(t1, TCGV_HIGH(arg1), c);
            tcg_gen_shri_i32(ret, arg1, c); 
            tcg_gen_or_i32(ret, ret, t0);
            tcg_gen_mov_i32(TCGV_HIGH(ret), t1);
        } else {
            tcg_gen_shri_i32(t0, arg1, 32 - c);
            /* Note: ret can be the same as arg1, so we use t1 */
            tcg_gen_shli_i32(t1, arg1, c); 
            tcg_gen_shli_i32(TCGV_HIGH(ret), TCGV_HIGH(arg1), c);
            tcg_gen_or_i32(TCGV_HIGH(ret), TCGV_HIGH(ret), t0);
            tcg_gen_mov_i32(ret, t1);
        }
    }
}
#endif

void tcg_reg_alloc_start(TCGContext *s)
{
    int i;
    TCGTemp *ts;
    for(i = 0; i < s->nb_globals; i++) {
        ts = &s->temps[i];
        if (ts->fixed_reg) {
            ts->val_type = TEMP_VAL_REG;
        } else {
            ts->val_type = TEMP_VAL_MEM;
        }
    }
    for(i = 0; i < TCG_TARGET_NB_REGS; i++) {
        s->reg_to_temp[i] = -1;
    }
}

static char *tcg_get_arg_str_idx(TCGContext *s, char *buf, int buf_size,
                                 int idx)
{
    TCGTemp *ts;

    ts = &s->temps[idx];
    if (idx < s->nb_globals) {
        pstrcpy(buf, buf_size, ts->name);
    } else {
        if (ts->val_type == TEMP_VAL_CONST) {
            snprintf(buf, buf_size, "$0x%" TCG_PRIlx , ts->val);
        } else {
            snprintf(buf, buf_size, "tmp%d", idx - s->nb_globals);
        }
    }
    return buf;
}

char *tcg_get_arg_str(TCGContext *s, char *buf, int buf_size, TCGv arg)
{
    return tcg_get_arg_str_idx(s, buf, buf_size, GET_TCGV(arg));
}

void tcg_dump_ops(TCGContext *s, FILE *outfile)
{
    const uint16_t *opc_ptr;
    const TCGArg *args;
    TCGArg arg;
    int c, i, k, nb_oargs, nb_iargs, nb_cargs;
    const TCGOpDef *def;
    char buf[128];

    opc_ptr = gen_opc_buf;
    args = gen_opparam_buf;
    while (opc_ptr < gen_opc_ptr) {
        c = *opc_ptr++;
        def = &tcg_op_defs[c];
        fprintf(outfile, " %s ", def->name);
        if (c == INDEX_op_call) {
            TCGArg arg;
            /* variable number of arguments */
            arg = *args++;
            nb_oargs = arg >> 16;
            nb_iargs = arg & 0xffff;
            nb_cargs = def->nb_cargs;

            /* function name */
            /* XXX: dump helper name for call */
            fprintf(outfile, "%s",
                    tcg_get_arg_str_idx(s, buf, sizeof(buf), args[nb_oargs + nb_iargs - 1]));
            /* flags */
            fprintf(outfile, ",$0x%" TCG_PRIlx,
                    args[nb_oargs + nb_iargs]);
            /* nb out args */
            fprintf(outfile, ",$%d", nb_oargs);
            for(i = 0; i < nb_oargs; i++) {
                fprintf(outfile, ",");
                fprintf(outfile, "%s",
                        tcg_get_arg_str_idx(s, buf, sizeof(buf), args[i]));
            }
            for(i = 0; i < (nb_iargs - 1); i++) {
                fprintf(outfile, ",");
                fprintf(outfile, "%s",
                        tcg_get_arg_str_idx(s, buf, sizeof(buf), args[nb_oargs + i]));
            }
        } else {
            if (c == INDEX_op_nopn) {
                /* variable number of arguments */
                nb_cargs = *args;
                nb_oargs = 0;
                nb_iargs = 0;
            } else {
                nb_oargs = def->nb_oargs;
                nb_iargs = def->nb_iargs;
                nb_cargs = def->nb_cargs;
            }
            
            k = 0;
            for(i = 0; i < nb_oargs; i++) {
                if (k != 0)
                    fprintf(outfile, ",");
                fprintf(outfile, "%s",
                        tcg_get_arg_str_idx(s, buf, sizeof(buf), args[k++]));
            }
            for(i = 0; i < nb_iargs; i++) {
                if (k != 0)
                    fprintf(outfile, ",");
                fprintf(outfile, "%s",
                        tcg_get_arg_str_idx(s, buf, sizeof(buf), args[k++]));
            }
            for(i = 0; i < nb_cargs; i++) {
                if (k != 0)
                    fprintf(outfile, ",");
                arg = args[k++];
                fprintf(outfile, "$0x%" TCG_PRIlx, arg);
            }
        }
        fprintf(outfile, "\n");
        args += nb_iargs + nb_oargs + nb_cargs;
    }
}

/* we give more priority to constraints with less registers */
static int get_constraint_priority(const TCGOpDef *def, int k)
{
    const TCGArgConstraint *arg_ct;

    int i, n;
    arg_ct = &def->args_ct[k];
    if (arg_ct->ct & TCG_CT_ALIAS) {
        /* an alias is equivalent to a single register */
        n = 1;
    } else {
        if (!(arg_ct->ct & TCG_CT_REG))
            return 0;
        n = 0;
        for(i = 0; i < TCG_TARGET_NB_REGS; i++) {
            if (tcg_regset_test_reg(arg_ct->u.regs, i))
                n++;
        }
    }
    return TCG_TARGET_NB_REGS - n + 1;
}

/* sort from highest priority to lowest */
static void sort_constraints(TCGOpDef *def, int start, int n)
{
    int i, j, p1, p2, tmp;

    for(i = 0; i < n; i++)
        def->sorted_args[start + i] = start + i;
    if (n <= 1)
        return;
    for(i = 0; i < n - 1; i++) {
        for(j = i + 1; j < n; j++) {
            p1 = get_constraint_priority(def, def->sorted_args[start + i]);
            p2 = get_constraint_priority(def, def->sorted_args[start + j]);
            if (p1 < p2) {
                tmp = def->sorted_args[start + i];
                def->sorted_args[start + i] = def->sorted_args[start + j];
                def->sorted_args[start + j] = tmp;
            }
        }
    }
}

void tcg_add_target_add_op_defs(const TCGTargetOpDef *tdefs)
{
    int op;
    TCGOpDef *def;
    const char *ct_str;
    int i, nb_args;

    for(;;) {
        if (tdefs->op < 0)
            break;
        op = tdefs->op;
        assert(op >= 0 && op < NB_OPS);
        def = &tcg_op_defs[op];
        nb_args = def->nb_iargs + def->nb_oargs;
        for(i = 0; i < nb_args; i++) {
            ct_str = tdefs->args_ct_str[i];
            tcg_regset_clear(def->args_ct[i].u.regs);
            def->args_ct[i].ct = 0;
            if (ct_str[0] >= '0' && ct_str[0] <= '9') {
                int oarg;
                oarg = ct_str[0] - '0';
                assert(oarg < def->nb_oargs);
                assert(def->args_ct[oarg].ct & TCG_CT_REG);
                /* TCG_CT_ALIAS is for the output arguments. The input
                   argument is tagged with TCG_CT_IALIAS. */
                def->args_ct[i] = def->args_ct[oarg];
                def->args_ct[oarg].ct = TCG_CT_ALIAS;
                def->args_ct[oarg].alias_index = i;
                def->args_ct[i].ct |= TCG_CT_IALIAS;
                def->args_ct[i].alias_index = oarg;
            } else {
                for(;;) {
                    if (*ct_str == '\0')
                        break;
                    switch(*ct_str) {
                    case 'i':
                        def->args_ct[i].ct |= TCG_CT_CONST;
                        ct_str++;
                        break;
                    default:
                        if (target_parse_constraint(&def->args_ct[i], &ct_str) < 0) {
                            fprintf(stderr, "Invalid constraint '%s' for arg %d of operation '%s'\n",
                                    ct_str, i, def->name);
                            exit(1);
                        }
                    }
                }
            }
        }

        /* sort the constraints (XXX: this is just an heuristic) */
        sort_constraints(def, 0, def->nb_oargs);
        sort_constraints(def, def->nb_oargs, def->nb_iargs);

#if 0
        {
            int i;

            printf("%s: sorted=", def->name);
            for(i = 0; i < def->nb_oargs + def->nb_iargs; i++)
                printf(" %d", def->sorted_args[i]);
            printf("\n");
        }
#endif
        tdefs++;
    }

}

#ifdef USE_LIVENESS_ANALYSIS

/* set a nop for an operation using 'nb_args' */
static inline void tcg_set_nop(TCGContext *s, uint16_t *opc_ptr, 
                               TCGArg *args, int nb_args)
{
    if (nb_args == 0) {
        *opc_ptr = INDEX_op_nop;
    } else {
        *opc_ptr = INDEX_op_nopn;
        args[0] = nb_args;
        args[nb_args - 1] = nb_args;
    }
}

/* liveness analysis: end of basic block: globals are live, temps are dead */
static inline void tcg_la_bb_end(TCGContext *s, uint8_t *dead_temps)
{
    memset(dead_temps, 0, s->nb_globals);
    memset(dead_temps + s->nb_globals, 1, s->nb_temps - s->nb_globals);
}

/* Liveness analysis : update the opc_dead_iargs array to tell if a
   given input arguments is dead. Instructions updating dead
   temporaries are removed. */
void tcg_liveness_analysis(TCGContext *s)
{
    int i, op_index, op, nb_args, nb_iargs, nb_oargs, arg, nb_ops;
    TCGArg *args;
    const TCGOpDef *def;
    uint8_t *dead_temps;
    unsigned int dead_iargs;
    
    gen_opc_ptr++; /* skip end */

    nb_ops = gen_opc_ptr - gen_opc_buf;

    /* XXX: make it really dynamic */
    s->op_dead_iargs = tcg_malloc(OPC_BUF_SIZE * sizeof(uint16_t));
    
    dead_temps = tcg_malloc(s->nb_temps);
    memset(dead_temps, 1, s->nb_temps);

    args = gen_opparam_ptr;
    op_index = nb_ops - 1;
    while (op_index >= 0) {
        op = gen_opc_buf[op_index];
        def = &tcg_op_defs[op];
        switch(op) {
        case INDEX_op_call: