iverilog/tgt-vlog95/numbers.c

388 lines
12 KiB
C

/*
* Copyright (C) 2011-2014 Cary R. (cygcary@yahoo.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
# include <math.h>
# include <stdlib.h>
# include <string.h>
# include "config.h"
# include "vlog95_priv.h"
/*
* Extract an int32_t value from the given bit information. If the result
* type is 0 then the returned value is valid. If it is positive then the
* value was too large and if it is negative then the value had undefined
* bits. -2 is all bits z and -3 is all bits x.
*/
static int32_t get_int32_from_bits(const char *bits, unsigned nbits,
unsigned is_signed, int *result_type)
{
unsigned trim_wid = nbits - 1;
const char msb = is_signed ? bits[trim_wid] : '0';
unsigned idx;
int32_t value = 0;
/* Trim any duplicate bits from the MSB. */
for (/* none */; trim_wid > 0; trim_wid -= 1) {
if (msb != bits[trim_wid]) {
trim_wid += 1;
break;
}
}
if (trim_wid < nbits) trim_wid += 1;
/* Check to see if the value is too large. */
if (trim_wid > 32U) {
*result_type = trim_wid;
return 0;
}
/* Now build the value from the bits. */
for (idx = 0; idx < trim_wid; idx += 1) {
if (bits[idx] == '1') value |= (int32_t)1 << idx;
else if (bits[idx] != '0') {
*result_type = -1;
/* If the value is entirely x/z then return -2 or -3. */
if (trim_wid == 1) {
if (bits[idx] == 'x') *result_type -= 1;
*result_type -= 1;
}
return 0;
}
}
/* Sign extend as needed. */
// HERE: Need to emit 1 instead of -1 for some of the constants.
// if (is_signed && (nbits > 1) && (msb == '1') && (trim_wid < 32U)) {
if (is_signed && (msb == '1') && (trim_wid < 32U)) {
value |= ~(((int32_t)1 << trim_wid) - (int32_t)1);
}
*result_type = 0;
return value;
}
/* Emit the given bits as either a signed or unsigned constant. If the
* bits contain an undefined value then emit them as a binary constant
* otherwise emit them as a hex constant. */
static void emit_bits(const char *bits, unsigned nbits, unsigned is_signed)
{
unsigned has_undef = 0;
assert(nbits > 0);
/* Check for an undefined bit. */
for (int idx = (int)nbits-1; idx >= 0; idx -= 1) {
if ((bits[idx] != '0') && (bits[idx] != '1')) {
has_undef = 1;
break;
}
}
fprintf(vlog_out, "%u'", nbits);
if (is_signed) fprintf(vlog_out, "s");
/* Emit as a binary constant. */
if (has_undef || (nbits < 2)) {
int start = nbits - 1;
char sbit = bits[start];
/* Trim extra leading bits. */
if (! is_signed && (sbit == '1')) sbit = ' ';
while (start && (sbit == bits[start-1])) start -= 1;
/* Print the trimmed value. */
fprintf(vlog_out, "b");
for (int idx = start; idx >= 0; idx -= 1) {
fprintf(vlog_out, "%c", bits[idx]);
}
/* Emit as a hex constant. */
} else {
unsigned start = 4*(nbits/4);
unsigned result = 0;
fprintf(vlog_out, "h");
/* The first digit may not be a full hex digit. */
if (start < nbits) {
for (unsigned idx = start; idx < nbits; idx += 1) {
if (bits[idx] == '1') result |= 1U << (idx%4);
}
fprintf(vlog_out, "%1x", result);
}
/* Now print the full hex digits. */
for (int idx = start-1; idx >= 0; idx -= 4) {
result = 0;
if (bits[idx] == '1') result |= 0x8;
if (bits[idx-1] == '1') result |= 0x4;
if (bits[idx-2] == '1') result |= 0x2;
if (bits[idx-3] == '1') result |= 0x1;
fprintf(vlog_out, "%1x", result);
}
}
}
void emit_number(const char *bits, unsigned nbits, unsigned is_signed,
const char *file, unsigned lineno)
{
/* If the user is allowing signed constructs then we can emit a
* signed number as a normal integer or with the 's syntax if
* an integer is not appropriate. */
if (is_signed && allow_signed) {
int rtype;
int32_t value = get_int32_from_bits(bits, nbits, 1, &rtype);
if (rtype != 0) emit_bits(bits, nbits, is_signed);
else fprintf(vlog_out, "%"PRId32, value);
/* Otherwise a signed value can only be 32 bits long since it can
* only be represented as an integer. We can trim any matching MSB
* bits to make it fit. We cannot support individual undefined
* bits in the constant. */
} else if (is_signed) {
int rtype;
int32_t value = get_int32_from_bits(bits, nbits, 1, &rtype);
if (rtype > 0) {
fprintf(vlog_out, "<invalid>");
fprintf(stderr, "%s:%u: vlog95 error: Signed number is "
"greater than 32 bits (%d) and cannot be "
"safely represented.\n", file, lineno,
rtype);
vlog_errors += 1;
} else if (rtype == -1) {
fprintf(vlog_out, "<invalid>");
fprintf(stderr, "%s:%u: vlog95 error: Signed number has "
"an undefined bit and cannot be "
"represented.\n", file, lineno);
vlog_errors += 1;
return;
} else if (rtype == -2) {
fprintf(vlog_out, "%u'bz", nbits);
} else if (rtype == -3) {
/* If this is a 32-bit wide constant then generate the
* undefined with integers to get a signed value. */
if (nbits == 32) fprintf(vlog_out, "1/0");
else fprintf(vlog_out, "%u'bx", nbits);
} else {
fprintf(vlog_out, "%"PRId32, value);
}
/* An unsigned number is represented in hex if all the bits are
* defined and it is more than a single bit otherwise it is
* represented in binary form to preserve all the information. */
} else {
emit_bits(bits, nbits, is_signed);
}
}
void emit_real_number(double value)
{
/* Check for NaN. */
if (isnan(value)) {
fprintf(vlog_out, "(0.0/0.0)");
return;
}
/* Check for the infinities. */
if (isinf(value)) {
if (signbit(value)) fprintf(vlog_out, "(-1.0/0.0)");
else fprintf(vlog_out, "(1.0/0.0)");
return;
}
/* Check for +/- zero. */
if (value == 0.0) {
if (signbit(value)) fprintf(vlog_out, "-0.0");
else fprintf(vlog_out, "0.0");
} else {
char buffer[32];
char *cptr;
unsigned len;
/* Print the double to a temporary string using an extra digit. */
buffer[sizeof(buffer)-1] = 0;
snprintf(buffer, sizeof(buffer), "%#.17g", value);
assert(buffer[sizeof(buffer)-1] == 0);
/* Check to see if there is a digit after the decimal point and
* add a digit if it is missing. */
len = strlen(buffer);
if (buffer[len-1] == '.') {
assert((len + 1) < sizeof(buffer));
buffer[len] = '0';
len += 1;
buffer[len] = 0;
}
/* Now trim any extra trailing zero digits. */
cptr = buffer + len - 1;
while ((*cptr == '0') && (*(cptr-1) != '.')) cptr -= 1;
*(cptr+1) = 0;
/* Now print the processed output. */
fprintf(vlog_out, "%s", buffer);
}
}
/*
* Extract an uint64_t value from the given number expression. If the result
* type is 0 then the returned value is valid. If it is positive then the
* value was too large and if it is negative then the value had undefined
* bits.
*/
uint64_t get_uint64_from_number(ivl_expr_t expr, int *result_type)
{
unsigned nbits = ivl_expr_width(expr);
unsigned trim_wid = nbits - 1;
const char *bits = ivl_expr_bits(expr);
unsigned idx;
uint64_t value = 0;
assert(ivl_expr_type(expr) == IVL_EX_NUMBER);
assert(! ivl_expr_signed(expr));
/* Trim any '0' bits from the MSB. */
for (/* none */; trim_wid > 0; trim_wid -= 1) {
if ('0' != bits[trim_wid]) {
trim_wid += 1;
break;
}
}
if (trim_wid < nbits) trim_wid += 1;
/* Check to see if the value is too large. */
if (trim_wid > 64U) {
*result_type = trim_wid;
return 0;
}
/* Now build the value from the bits. */
for (idx = 0; idx < trim_wid; idx += 1) {
if (bits[idx] == '1') value |= (uint64_t)1 << idx;
else if (bits[idx] != '0') {
*result_type = -1;
/* If the value is entirely x/z then return -2 or -3. */
if (trim_wid == 1) {
if (bits[idx] == 'x') *result_type -= 1;
*result_type -= 1;
}
return 0;
}
}
*result_type = 0;
return value;
}
/*
* Extract an int64_t value from the given number expression. If the result
* type is 0 then the returned value is valid. If it is positive then the
* value was too large and if it is negative then the value had undefined
* bits. -2 is all bits z and -3 is all bits x.
*/
int64_t get_int64_from_number(ivl_expr_t expr, int *result_type)
{
unsigned is_signed = ivl_expr_signed(expr);
unsigned nbits = ivl_expr_width(expr);
unsigned trim_wid = nbits - 1;
const char *bits = ivl_expr_bits(expr);
const char msb = is_signed ? bits[trim_wid] : '0';
unsigned idx;
int64_t value = 0;
assert(ivl_expr_type(expr) == IVL_EX_NUMBER);
/* Trim any duplicate bits from the MSB. */
for (/* none */; trim_wid > 0; trim_wid -= 1) {
if (msb != bits[trim_wid]) {
trim_wid += 1;
break;
}
}
if (trim_wid < nbits) trim_wid += 1;
/* Check to see if the value is too large. */
if (trim_wid > 64U) {
*result_type = trim_wid;
return 0;
}
/* Now build the value from the bits. */
for (idx = 0; idx < trim_wid; idx += 1) {
if (bits[idx] == '1') value |= (int64_t)1 << idx;
else if (bits[idx] != '0') {
*result_type = -1;
/* If the value is entirely x/z then return -2 or -3. */
if (trim_wid == 1) {
if (bits[idx] == 'x') *result_type -= 1;
*result_type -= 1;
}
return 0;
}
}
/* Sign extend as needed. */
if (is_signed && (msb == '1') && (trim_wid < 64U)) {
value |= ~(((int64_t)1 << trim_wid) - (int64_t)1);
}
*result_type = 0;
return value;
}
/*
* Extract an int32_t value from the given number expression. If the result
* type is 0 then the returned value is valid. If it is positive then the
* value was too large and if it is negative then the value had undefined
* bits. -2 is all bits z and -3 is all bits x.
*/
int32_t get_int32_from_number(ivl_expr_t expr, int *result_type)
{
assert(ivl_expr_type(expr) == IVL_EX_NUMBER);
return get_int32_from_bits(ivl_expr_bits(expr), ivl_expr_width(expr),
ivl_expr_signed(expr), result_type);
}
/*
* Routine to remove two characters starting at the given address.
*/
static void remove_two_chars(char* str)
{
for (; str[2]; str += 1) {
str[0] = str[2];
}
str[0] = 0;
}
/*
* Routine to print a string value as a string after removing any leading
* escaped NULL bytes.
*/
void emit_string(const char* string)
{
char *buffer = strdup(string);
char *bptr = buffer;
char *cptr;
fprintf(vlog_out, "\"");
/* Prune any leading escaped NULL bytes. */
while ((bptr[0] == '\\') && (bptr[1] == '0') &&
(bptr[2] == '0') && (bptr[3] == '0')) bptr += 4;
for (cptr = bptr; *cptr; cptr += 1) {
if (*cptr == '\\') {
/* Replace any \011 with \t */
if ((cptr[1] == '0') && (cptr[2] == '1') &&
(cptr[3] == '1')) {
cptr[1] = 't';
remove_two_chars(cptr+2);
cptr += 1;
/* Replace any \012 with \n */
} else if ((cptr[1] == '0') && (cptr[2] == '1') &&
(cptr[3] == '2')) {
cptr[1] = 'n';
remove_two_chars(cptr+2);
cptr += 1;
/* Replace any \042 with \" */
} else if ((cptr[1] == '0') && (cptr[2] == '4') &&
(cptr[3] == '2')) {
cptr[1] = '"';
remove_two_chars(cptr+2);
cptr += 1;
/* Replace any \134 with \\ */
} else if ((cptr[1] == '1') && (cptr[2] == '3') &&
(cptr[3] == '4')) {
cptr[1] = '\\';
remove_two_chars(cptr+2);
cptr += 1;
} else cptr += 3;
}
}
if (*bptr) fprintf(vlog_out, "%s", bptr);
free(buffer);
fprintf(vlog_out, "\"");
}