void reset_registers(void)
{
int i;
for(i = 0; i < NUM_REGS; ++i) {
mp_int_zero(g_zreg + i);
mp_rat_zero(g_qreg + i);
}
}
/*
Compute mul * atan(1/x) to prec digits of precision, and store the
result in sum.
Computes atan(1/x) using the formula:
1 1 1 1
atan(1/x) = --- - ---- + ---- - ---- + ...
x 3x^3 5x^5 7x^7
*/
mp_result arctan(mp_small radix, mp_small mul, mp_small x, mp_small prec,
mp_int sum) {
mpz_t t, v;
mp_result res;
mp_small rem, sign = 1, coeff = 1;
mp_int_init(&t);
mp_int_init(&v);
++prec;
/* Compute mul * radix^prec * x
The initial multiplication by x saves a special case in the loop for
the first term of the series.
*/
if ((res = mp_int_expt_value(radix, prec, &t)) != MP_OK ||
(res = mp_int_mul_value(&t, mul, &t)) != MP_OK ||
(res = mp_int_mul_value(&t, x, &t)) != MP_OK)
goto CLEANUP;
x *= x; /* assumes x <= sqrt(MP_SMALL_MAX) */
mp_int_zero(sum);
do {
if ((res = mp_int_div_value(&t, x, &t, &rem)) != MP_OK) goto CLEANUP;
if ((res = mp_int_div_value(&t, coeff, &v, &rem)) != MP_OK) goto CLEANUP;
/* Add or subtract the result depending on the current sign (1 = add) */
if (sign > 0)
res = mp_int_add(sum, &v, sum);
else
res = mp_int_sub(sum, &v, sum);
if (res != MP_OK) goto CLEANUP;
sign = -sign;
coeff += 2;
} while (mp_int_compare_zero(&t) != 0);
res = mp_int_div_value(sum, radix, sum, NULL);
CLEANUP:
mp_int_clear(&v);
mp_int_clear(&t);
return res;
}
static int parse_int_values(testspec_t *t, mp_int *in, mp_int *out,
mp_result *rval)
{
int i, pos = 0;
char *str;
if(rval != NULL)
*rval = MP_OK; /* default */
if(in != NULL) {
for(i = 0; i < t->num_inputs; ++i) {
str = t->input[i];
trim_line(str);
if(*str == '=') {
int k = abs(atoi(str + 1)) - 1;
if(k < 0 || k >= i) {
fprintf(stderr, "Line %d: Invalid input back-reference [%s]\n",
t->line, str);
return 0;
}
in[i] = in[k];
} else {
mp_int reg = g_zreg + pos++; /* grab next free register */
if(read_int_value(reg, str) != MP_OK) {
fprintf(stderr, "Line %d: Invalid input value [%s]\n",
t->line, str);
return 0;
}
in[i] = reg;
}
}
}
for(i = 0; i < t->num_outputs; ++i) {
mp_int reg = g_zreg + pos++;
str = t->output[i];
trim_line(str);
if(strcmp(str, "?") == 0)
mp_int_zero(reg);
else if(*str == '$') {
mp_result code;
if(!parse_result_code(str, &code)) {
fprintf(stderr, "Line %d: Invalid result code [%s]\n",
t->line, str);
return 0;
}
else if(rval == NULL) {
fprintf(stderr, "Line %d: Result code not permitted here [%s]\n",
t->line, str);
return 0;
}
else
*rval = code;
/* Provide a dummy value for the corresponding output */
mp_int_zero(reg);
}
else if(out != NULL && read_int_value(reg, str) != MP_OK) {
fprintf(stderr, "Line %d: Invalid output value [%s]\n",
t->line, str);
return 0;
}
if(out != NULL)
out[i] = reg;
}
return 1;
}
