iverilog/tgt-vlog95/expr.c

1252 lines
42 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 <inttypes.h>
# include <string.h>
# include "config.h"
# include "vlog95_priv.h"
/* The expression code needs to know when a parameter definition is being
* emitted so it can print the numeric value instead of the parameter name. */
ivl_parameter_t emitting_param = 0;
/*
* Data type used to signify if a $signed or $unsigned should be emitted.
*/
typedef enum expr_sign_e {
NO_SIGN = 0,
NEED_SIGNED = 1,
NEED_UNSIGNED = 2
} expr_sign_t;
static expr_sign_t expr_get_binary_sign_type(ivl_expr_t expr)
{
ivl_expr_t oper1, oper2;
int opr_sign = 0;
int expr_sign = ivl_expr_signed(expr);
expr_sign_t rtn = NO_SIGN;
switch (ivl_expr_opcode(expr)) {
case 'E':
case 'e':
case 'N':
case 'n':
case '<':
case 'L':
case '>':
case 'G':
/* The comparison operators always act as if the argument is
* unsigned. */
break;
case 'l':
case 'r':
case 'R':
/* For the shift operators only the left operand is used to
* determine the sign information. */
opr_sign = ivl_expr_signed(ivl_expr_oper1(expr));
break;
default:
/* For the rest of the opcodes the operator is considered to
* be signed if either argument is real or if both arguments
* are signed. */
oper1 = ivl_expr_oper1(expr);
oper2 = ivl_expr_oper2(expr);
if ((ivl_expr_value(oper1) == IVL_VT_REAL) ||
(ivl_expr_value(oper2) == IVL_VT_REAL)) {
opr_sign = 1;
} else if (ivl_expr_signed(oper1) && ivl_expr_signed(oper2)) {
opr_sign = 1;
}
break;
}
/* Check to see if a $signed() or $unsigned() is needed. */
if (expr_sign && ! opr_sign) rtn = NEED_SIGNED;
if (! expr_sign && opr_sign) rtn = NEED_UNSIGNED;
return rtn;
}
static expr_sign_t expr_get_select_sign_type(ivl_expr_t expr,
unsigned can_skip_unsigned)
{
int opr_sign = 0;
int expr_sign = ivl_expr_signed(expr);
expr_sign_t rtn = NO_SIGN;
/* If there is no select expression then the sign is determined by
* the expression that is being selected (padded). */
if (! ivl_expr_oper2(expr)) {
ivl_expr_t oper1 = ivl_expr_oper1(expr);
opr_sign = ivl_expr_signed(oper1);
/* If the expression being padded is not a signal then don't
* skip a soft $unsigned() (from the binary operator). */
if (ivl_expr_type(oper1) != IVL_EX_SIGNAL) can_skip_unsigned -= 1;
}
/* Check to see if a $signed() or $unsigned() is needed. */
if (expr_sign && ! opr_sign) rtn = NEED_SIGNED;
if (! expr_sign && opr_sign && ! can_skip_unsigned) rtn = NEED_UNSIGNED;
return rtn;
}
static expr_sign_t expr_get_signal_sign_type(ivl_expr_t expr,
unsigned can_skip_unsigned)
{
int opr_sign = ivl_signal_signed(ivl_expr_signal(expr));
int expr_sign = ivl_expr_signed(expr);
expr_sign_t rtn = NO_SIGN;
/* Check to see if a $signed() or $unsigned() is needed. */
if (expr_sign && ! opr_sign) rtn = NEED_SIGNED;
if (! expr_sign && opr_sign && ! can_skip_unsigned) rtn = NEED_UNSIGNED;
return rtn;
}
static expr_sign_t expr_get_unary_sign_type(ivl_expr_t expr)
{
ivl_expr_t expr1;
int opr_sign = 0;
int expr_sign = ivl_expr_signed(expr);
expr_sign_t rtn = NO_SIGN;
switch (ivl_expr_opcode(expr)) {
case '&':
case '|':
case '^':
case 'A':
case 'N':
case 'X':
/* The reduction operators always act as if the argument is
* unsigned. */
break;
case 'r':
/* For a cast to real the expression should be signed and no
* sign conversion is needed. */
opr_sign = expr_sign;
if (! expr_sign) {
fprintf(stderr, "%s:%u: vlog95 error: Cast to real "
"expression is not signed.\n",
ivl_expr_file(expr), ivl_expr_lineno(expr));
vlog_errors += 1;
}
break;
case '2':
case 'v':
/* If the cast to a vector value is from a real then no sign
* conversion is needed. Otherwise use the actual argument. */
expr1 = ivl_expr_oper1(expr);
if (ivl_expr_value(expr1) == IVL_VT_REAL) {
opr_sign = expr_sign;
} else {
opr_sign = ivl_expr_signed(expr1);
}
break;
default:
/* For the rest of the opcodes the argument sign type depends
* on the actual argument. */
opr_sign = ivl_expr_signed(ivl_expr_oper1(expr));
break;
}
/* Check to see if a $signed() or $unsigned() is needed. */
if (expr_sign && ! opr_sign) rtn = NEED_SIGNED;
if (! expr_sign && opr_sign) rtn = NEED_UNSIGNED;
return rtn;
}
/*
* This routine is used to determine if the expression is a binary operator
* where the width could be different to create a self-determined context.
*/
static unsigned expr_is_binary_self_det(ivl_expr_t expr)
{
unsigned rtn = 0;
if (ivl_expr_type(expr) == IVL_EX_BINARY) {
switch (ivl_expr_opcode(expr)) {
case '+':
case '-':
case '*':
case '/':
case '%':
case '&':
case '|':
case '^':
case 'X':
case 'A':
case 'O':
case 'R':
case 'l':
case 'r':
rtn = 1;
break;
default:
break;
}
}
return rtn;
}
/*
* Determine if a $signed() or $unsigned() system function is needed to get
* the expression sign information correct. can_skip_unsigned may be set for
* the binary/ternary operators if one of the operands will implicitly cast
* the expression to unsigned. See calc_can_skip_unsigned() for the details.
*/
static expr_sign_t expr_get_sign_type(ivl_expr_t expr, unsigned wid,
unsigned can_skip_unsigned,
unsigned is_full_prec)
{
unsigned expr_wid = ivl_expr_width(expr);
expr_sign_t rtn = NO_SIGN;
ivl_expr_type_t type = ivl_expr_type(expr);
switch (type) {
case IVL_EX_BINARY:
rtn = expr_get_binary_sign_type(expr);
break;
case IVL_EX_CONCAT:
/* A concatenation is always unsigned so add a $signed() when
* needed. */
if (ivl_expr_signed(expr)) rtn = NEED_SIGNED;
break;
case IVL_EX_SELECT:
rtn = expr_get_select_sign_type(expr, can_skip_unsigned);
/* If there is no select expression then this is padding so use
* the actual expressions width if it is a binary operator that
* could create a self-determined context. */
if (! ivl_expr_oper2(expr)) {
ivl_expr_t oper1 = ivl_expr_oper1(expr);
if (expr_is_binary_self_det(oper1)) {
expr_wid = ivl_expr_width(oper1);
}
}
break;
case IVL_EX_SIGNAL:
rtn = expr_get_signal_sign_type(expr, can_skip_unsigned);
break;
case IVL_EX_UNARY:
rtn = expr_get_unary_sign_type(expr);
break;
/* These do not currently have sign casting information. A select
* is used for that purpose. */
case IVL_EX_ARRAY:
case IVL_EX_DELAY:
case IVL_EX_ENUMTYPE:
case IVL_EX_EVENT:
case IVL_EX_NEW:
case IVL_EX_NULL:
case IVL_EX_NUMBER:
case IVL_EX_PROPERTY:
case IVL_EX_REALNUM:
case IVL_EX_SCOPE:
case IVL_EX_SFUNC:
case IVL_EX_SHALLOWCOPY:
case IVL_EX_STRING:
case IVL_EX_TERNARY:
case IVL_EX_UFUNC:
default:
break;
}
/* Check for a self-determined context. A zero width expression
* is special and is not considered a self determined context. */
if ((rtn == NO_SIGN) && (wid != expr_wid) && expr_wid &&
! (is_full_prec && ((expr_wid < wid) || (type == IVL_EX_SIGNAL)))) {
if (ivl_expr_signed(expr)) rtn = NEED_SIGNED;
else rtn = NEED_UNSIGNED;
}
return rtn;
}
/*
* We can convert any 2^n ** <unsigned variable> expression to
* 1 << (n * <unsigned variable>). If the variable is signed then we need
* to add a check for less than zero and for that case return 0.
*/
static unsigned emit_power_as_shift(ivl_scope_t scope, ivl_expr_t expr,
unsigned wid)
{
int rtype;
int64_t value, scale;
unsigned is_signed_rval = 0;
unsigned is_signed_expr = ivl_expr_signed(expr);
unsigned expr_wid;
ivl_expr_t lval = ivl_expr_oper1(expr);
ivl_expr_t rval = ivl_expr_oper2(expr);
(void)wid; /* Parameter is not used. */
/* The L-value must be a number. */
if (ivl_expr_type(lval) != IVL_EX_NUMBER) return 0;
/* The L-value must of the form 2^n. */
value = get_int64_from_number(lval, &rtype);
if (rtype) return 0;
expr_wid = ivl_expr_width(lval);
if (value < 2) return 0;
if (value % 2) return 0;
/* Generate the appropriate conversion. */
if (ivl_expr_signed(rval)) {
emit_expr(scope, rval, 0, 0, 0, 0);
fprintf(vlog_out, " < 0 ? ");
if (is_signed_expr) {
if (expr_wid == 32) {
fprintf(vlog_out, "0");
} else if (allow_signed) {
fprintf(vlog_out, "%u'sh0", expr_wid);
} else {
fprintf(stderr, "%s:%u: vlog95 error: Sized signed "
"power operator l-value is not "
"supported.\n", ivl_expr_file(expr),
ivl_expr_lineno(expr));
vlog_errors += 1;
fprintf(vlog_out, "%u'h0", expr_wid);
}
} else {
fprintf(vlog_out, "%u'h0", expr_wid);
}
fprintf(vlog_out, " : (");
is_signed_rval = 1;
}
scale = value / 2;
if (is_signed_expr) {
if (expr_wid == 32) {
fprintf(vlog_out, "1");
} else if (allow_signed) {
fprintf(vlog_out, "%u'sh1", expr_wid);
} else {
/* This is an error condition and has already been
* reported above. */
fprintf(vlog_out, "%u'h1", expr_wid);
}
} else {
fprintf(vlog_out, "%u'h1", expr_wid);
}
fprintf(vlog_out, " << ");
if (scale != 1) {
if (is_signed_rval) {
fprintf(vlog_out, "(%"PRId64, scale);
} else {
fprintf(vlog_out, "(%u'h%"PRIx64,
ivl_expr_width(rval), scale);
}
fprintf(vlog_out, " * ");
}
emit_expr(scope, rval, 0, 0, 0, 0);
if (scale != 1) fprintf(vlog_out, ")");
if (is_signed_rval) fprintf(vlog_out, ")");
return 1;
}
static void emit_expr_array(ivl_scope_t scope, ivl_expr_t expr, unsigned wid)
{
ivl_signal_t sig = ivl_expr_signal(expr);
(void)wid; /* Parameter is not used. */
emit_scope_call_path(scope, ivl_signal_scope(sig));
emit_id(ivl_signal_basename(sig));
}
/*
* Some of the operators can do an implicit cast to real so for them emit
* the non-real argument in a self-determined context.
*/
static unsigned get_cast_width(ivl_expr_t expr, ivl_expr_t oper, unsigned wid)
{
ivl_variable_type_t expr_type = ivl_expr_value(expr);
if ((expr_type == IVL_VT_REAL) && (expr_type != ivl_expr_value(oper))) {
wid = 0;
}
return wid;
}
static unsigned calc_can_skip_unsigned(ivl_expr_t oper1, ivl_expr_t oper2)
{
unsigned oper1_signed, oper2_signed;
/* Check to see if the operands are signed or softly signed.
* The expression is signed (hard).
* It is a signed signal cast to unsigned (soft).
* It is a padding cast from signed to unsigned (soft). */
oper1_signed = ivl_expr_signed(oper1);
oper1_signed |= (ivl_expr_type(oper1) == IVL_EX_SIGNAL) &&
(ivl_signal_signed(ivl_expr_signal(oper1)));
oper1_signed |= (ivl_expr_type(oper1) == IVL_EX_SELECT) &&
(! ivl_expr_oper2(oper1)) &&
(ivl_expr_signed(ivl_expr_oper1(oper1)));
oper2_signed = ivl_expr_signed(oper2);
oper2_signed |= (ivl_expr_type(oper2) == IVL_EX_SIGNAL) &&
(ivl_signal_signed(ivl_expr_signal(oper2)));
oper2_signed |= (ivl_expr_type(oper2) == IVL_EX_SELECT) &&
(! ivl_expr_oper2(oper2)) &&
(ivl_expr_signed(ivl_expr_oper1(oper2)));
/* If either operand is a hard unsigned skip adding an explicit
* $unsigned() since it will be added implicitly. */
return ! oper1_signed || ! oper2_signed;
}
static void emit_expr_binary(ivl_scope_t scope, ivl_expr_t expr, unsigned wid,
unsigned is_full_prec)
{
const char *oper = "<invalid>";
ivl_expr_t oper1 = ivl_expr_oper1(expr);
ivl_expr_t oper2 = ivl_expr_oper2(expr);
unsigned can_skip_unsigned = calc_can_skip_unsigned(oper1, oper2);
switch (ivl_expr_opcode(expr)) {
case '+': oper = "+"; break;
case '-': oper = "-"; break;
case '*': oper = "*"; break;
case '/': oper = "/"; break;
case '%': oper = "%"; break;
case 'p': oper = "**"; break;
case 'E': oper = "==="; break;
case 'e': oper = "=="; break;
case 'N': oper = "!=="; break;
case 'n': oper = "!="; break;
case '<': oper = "<"; break;
case 'L': oper = "<="; break;
case '>': oper = ">"; break;
case 'G': oper = ">="; break;
case '&': oper = "&"; break;
case '|': oper = "|"; break;
case '^': oper = "^"; break;
case 'A': oper = "&"; break;
case 'O': oper = "|"; break;
case 'X': oper = "~^"; break;
case 'a': oper = "&&"; break;
case 'o': oper = "||"; break;
case 'l': oper = "<<"; break;
case 'r': oper = ">>"; break;
case 'R': oper = ">>>"; break;
case 'm': oper = "min"; break;
case 'M': oper = "max"; break;
}
fprintf(vlog_out, "(");
switch (ivl_expr_opcode(expr)) {
case '%':
if (ivl_expr_value(expr) == IVL_VT_REAL) {
fprintf(stderr, "%s:%u: vlog95 error: Real modulus operator "
"is not supported.\n",
ivl_expr_file(expr), ivl_expr_lineno(expr));
vlog_errors += 1;
}
case '+':
case '-':
case '*':
case '/':
emit_expr(scope, oper1, get_cast_width(expr, oper1, wid), 0,
can_skip_unsigned, is_full_prec);
fprintf(vlog_out, " %s ", oper);
emit_expr(scope, oper2, get_cast_width(expr, oper2, wid), 0,
can_skip_unsigned, is_full_prec);
break;
case '&':
case '|':
case '^':
case 'X':
emit_expr(scope, oper1, wid, 0, can_skip_unsigned, is_full_prec);
fprintf(vlog_out, " %s ", oper);
emit_expr(scope, oper2, wid, 0, can_skip_unsigned, is_full_prec);
break;
case 'E':
case 'e':
case 'N':
case 'n':
case '<':
case 'L':
case '>':
case 'G':
emit_expr(scope, oper1, ivl_expr_width(oper1), 0,
can_skip_unsigned, 0);
fprintf(vlog_out, " %s ", oper);
emit_expr(scope, oper2, ivl_expr_width(oper2), 0,
can_skip_unsigned, 0);
break;
case 'a':
case 'o':
emit_expr(scope, oper1, ivl_expr_width(oper1), 0, 1, 0);
fprintf(vlog_out, " %s ", oper);
emit_expr(scope, oper2, ivl_expr_width(oper2), 0, 1, 0);
break;
case 'R':
if (! allow_signed) {
fprintf(stderr, "%s:%u: vlog95 error: >>> operator is not "
"supported.\n",
ivl_expr_file(expr), ivl_expr_lineno(expr));
vlog_errors += 1;
}
case 'l':
case 'r':
emit_expr(scope, oper1, wid, 0, 0, 0);
fprintf(vlog_out, " %s ", oper);
emit_expr(scope, oper2, ivl_expr_width(oper2), 0, 2, 0);
break;
case 'A':
case 'O':
fprintf(vlog_out, "~(");
emit_expr(scope, oper1, wid, 0, can_skip_unsigned, is_full_prec);
fprintf(vlog_out, " %s ", oper);
emit_expr(scope, oper2, wid, 0, can_skip_unsigned, is_full_prec);
fprintf(vlog_out, ")");
break;
case 'p':
if (! emit_power_as_shift(scope, expr, wid)) {
emit_expr(scope, oper1, wid, 0, 0, is_full_prec);
fprintf(vlog_out, " ** ");
emit_expr(scope, oper2, ivl_expr_width(oper2), 0, 0, 0);
fprintf(stderr, "%s:%u: vlog95 error: Power operator is not "
"supported.\n",
ivl_expr_file(expr), ivl_expr_lineno(expr));
vlog_errors += 1;
}
break;
/* Convert the Verilog-A min() or max() functions. */
case 'm':
case 'M':
if (ivl_expr_value(expr) == IVL_VT_REAL) {
/* For a real expression use the $min()/$max() function. */
if (ivl_expr_opcode(expr) == 'm') fprintf(vlog_out, "$min(");
else fprintf(vlog_out, "$max(");
emit_expr(scope, oper1, wid, 0, 0, 0);
fprintf(vlog_out, ",");
emit_expr(scope, oper2, wid, 0, 0, 0);
fprintf(vlog_out, ")");
} else {
/* This only works when the argument has no side effect. */
fprintf(vlog_out, "((");
emit_expr(scope, oper1, wid, 0, 0, 0);
fprintf(vlog_out, ") %s (", oper);
emit_expr(scope, oper2, wid, 0, 0, 0);
fprintf(vlog_out, ") ? (");
emit_expr(scope, oper1, wid, 0, 0, 0);
fprintf(vlog_out, ") : (");
emit_expr(scope, oper2, wid, 0, 0, 0);
fprintf(vlog_out, "))");
}
break;
default:
emit_expr(scope, oper1, wid, 0, can_skip_unsigned, 0);
fprintf(vlog_out, "<unknown>");
emit_expr(scope, oper2, wid, 0, can_skip_unsigned, 0);
fprintf(stderr, "%s:%u: vlog95 error: Unknown expression "
"operator (%c).\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr),
ivl_expr_opcode(expr));
vlog_errors += 1;
break;
}
fprintf(vlog_out, ")");
}
static void emit_expr_concat(ivl_scope_t scope, ivl_expr_t expr, unsigned wid)
{
unsigned repeat = ivl_expr_repeat(expr);
unsigned idx, count = ivl_expr_parms(expr);
(void)wid; /* Parameter is not used. */
if (repeat != 1) fprintf(vlog_out, "{%u", repeat);
fprintf(vlog_out, "{");
count -= 1;
for (idx = 0; idx < count; idx += 1) {
emit_expr(scope, ivl_expr_parm(expr, idx), 0, 0, 0, 0);
fprintf(vlog_out, ", ");
}
emit_expr(scope, ivl_expr_parm(expr, count), 0, 0, 0, 0);
fprintf(vlog_out, "}");
if (repeat != 1) fprintf(vlog_out, "}");
}
static void emit_expr_delay(ivl_scope_t scope, ivl_expr_t expr, unsigned wid)
{
(void)wid; /* Parameter is not used. */
emit_scaled_delay(scope, ivl_expr_delay_val(expr));
}
/*
* An event in an expression context must be a named event.
*/
static void emit_expr_event(ivl_scope_t scope, ivl_expr_t expr, unsigned wid)
{
ivl_event_t event = ivl_expr_event(expr);
ivl_scope_t ev_scope = ivl_event_scope(event);
(void)wid; /* Parameter is not used. */
assert(! ivl_event_nany(event));
assert(! ivl_event_npos(event));
assert(! ivl_event_nneg(event));
emit_scope_call_path(scope, ev_scope);
emit_id(ivl_event_basename(event));
}
/*
* A number can also be a parameter reference. If it is a parameter
* reference then emit the appropriate parameter name instead of the
* numeric value unless this is the actual parameter definition.
*/
static void emit_expr_number(ivl_scope_t scope, ivl_expr_t expr, unsigned wid)
{
ivl_parameter_t param = ivl_expr_parameter(expr);
(void)wid; /* Parameter is not used. */
if (param && (param != emitting_param)) {
emit_scope_call_path(scope, ivl_parameter_scope(param));
emit_id(ivl_parameter_basename(param));
} else {
emit_number(ivl_expr_bits(expr), ivl_expr_width(expr),
ivl_expr_signed(expr), ivl_expr_file(expr),
ivl_expr_lineno(expr));
}
}
static void emit_expr_real_number(ivl_scope_t scope, ivl_expr_t expr,
unsigned wid)
{
ivl_parameter_t param = ivl_expr_parameter(expr);
(void)wid; /* Parameter is not used. */
if (param && (param != emitting_param)) {
emit_scope_call_path(scope, ivl_parameter_scope(param));
emit_id(ivl_parameter_basename(param));
} else {
emit_real_number(ivl_expr_dvalue(expr));
}
}
/*
* Class properties are not supported in vlog95, but they can be translated.
*/
static void emit_class_property(ivl_scope_t scope, ivl_expr_t expr, unsigned wid)
{
ivl_signal_t sig = ivl_expr_signal(expr);
(void)wid; /* Parameter is not used. */
emit_scope_call_path(scope, ivl_signal_scope(sig));
emit_id(ivl_signal_basename(sig));
fprintf(vlog_out, ".%s", ivl_expr_name(expr));
}
static void emit_expr_scope_piece(ivl_scope_t scope)
{
ivl_scope_t parent = ivl_scope_parent(scope);
/* If this scope has a parent then emit it first. */
if (parent) {
emit_expr_scope_piece(parent);
fprintf(vlog_out, ".");
}
emit_id(ivl_scope_basename(scope));
}
static void emit_expr_scope(ivl_scope_t scope, ivl_expr_t expr, unsigned wid)
{
(void)scope; /* Parameter is not used. */
(void)wid; /* Parameter is not used. */
emit_expr_scope_piece(ivl_expr_scope(expr));
}
static void emit_select_name(ivl_scope_t scope, ivl_expr_t expr)
{
/* A select of a number is really a parameter select. */
if (ivl_expr_type(expr) == IVL_EX_NUMBER) {
ivl_parameter_t param = ivl_expr_parameter(expr);
if (param) {
emit_scope_call_path(scope, ivl_parameter_scope(param));
emit_id(ivl_parameter_basename(param));
} else {
fprintf(vlog_out, "<missing>");
fprintf(stderr, "%s:%u: vlog95 error: Unable to find "
"parameter for select expression \n",
ivl_expr_file(expr), ivl_expr_lineno(expr));
vlog_errors += 1;
}
} else {
emit_expr(scope, expr, 0, 0, 0, 0);
}
}
/*
* Emit a packed array access as a concatenation of bit selects.
*/
static void emit_expr_packed(ivl_scope_t scope, ivl_expr_t sig_expr,
ivl_expr_t sel_expr, unsigned wid)
{
unsigned idx;
assert(wid > 0);
fprintf(vlog_out, "{");
for (idx = wid - 1; idx > 0; idx -= 1) {
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_expr(scope, sel_expr, 0, 0, 0, 1);
fprintf(vlog_out, " + %u], ", idx);
}
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_expr(scope, sel_expr, 0, 0, 0, 1);
fprintf(vlog_out, "]}");
}
/*
* Emit an indexed part select as a concatenation of bit selects. Since a
* parameter in 1364-1995 is always zero based the select expression needs
* to keep any scaling that was done by the compiler.
*/
static void emit_expr_ips(ivl_scope_t scope, ivl_expr_t sig_expr,
ivl_expr_t sel_expr, ivl_select_type_t sel_type,
unsigned wid, int msb, int lsb, unsigned is_param)
{
unsigned idx;
assert(wid > 0);
/* If it was not already given, note that a down index part select will
* require the -pallowsigned=1 flag to get the index values correct if
* the select expression is not signed. */
if ((! allow_signed ) && (sel_type == IVL_SEL_IDX_DOWN) &&
(! ivl_expr_signed(sel_expr))) {
fprintf(stderr, "%s:%u: vlog95 note: Translating a down indexed "
"part select requires the -pallowsigned=1 flag.\n",
ivl_expr_file(sel_expr), ivl_expr_lineno(sel_expr));
}
fprintf(vlog_out, "{");
if (msb >= lsb) {
if ((sel_type == IVL_SEL_IDX_DOWN) && ! is_param) {
lsb += wid - 1;
msb += wid - 1;
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_scaled_expr(scope, sel_expr, msb, lsb);
fprintf(vlog_out, "]");
for (idx = 1; idx < wid; idx += 1) {
fprintf(vlog_out, ", ");
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_scaled_expr(scope, sel_expr, msb, lsb);
fprintf(vlog_out, " - %u]", idx);
}
fprintf(vlog_out, "}");
} else {
assert((sel_type == IVL_SEL_IDX_UP) ||
(is_param && (sel_type == IVL_SEL_IDX_DOWN)));
for (idx = wid - 1; idx > 0; idx -= 1) {
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_scaled_expr(scope, sel_expr, msb, lsb);
fprintf(vlog_out, " + %u], ", idx);
}
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_scaled_expr(scope, sel_expr, msb, lsb);
fprintf(vlog_out, "]}");
}
} else {
if ((sel_type == IVL_SEL_IDX_UP) && ! is_param) {
lsb -= wid - 1;
msb -= wid - 1;
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_scaled_expr(scope, sel_expr, msb, lsb);
fprintf(vlog_out, "]");
for (idx = 1; idx < wid; idx += 1) {
fprintf(vlog_out, ", ");
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_scaled_expr(scope, sel_expr, msb, lsb);
fprintf(vlog_out, " + %u]", idx);
}
fprintf(vlog_out, "}");
} else {
assert((sel_type == IVL_SEL_IDX_DOWN) ||
(is_param && (sel_type == IVL_SEL_IDX_UP)));
for (idx = wid - 1; idx > 0; idx -= 1) {
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_scaled_expr(scope, sel_expr, msb, lsb);
fprintf(vlog_out, " - %u], ", idx);
}
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_scaled_expr(scope, sel_expr, msb, lsb);
fprintf(vlog_out, "]}");
}
}
}
static void check_select_signed(ivl_expr_t sig_expr, ivl_expr_t sel_expr,
int msb, int lsb)
{
expr_sign_t sign_type = expr_get_sign_type(sel_expr,
ivl_expr_width(sel_expr),
0, 1);
char msg[64];
snprintf(msg, sizeof(msg), "%s:%u",
ivl_expr_file(sel_expr),
ivl_expr_lineno(sel_expr));
msg[sizeof(msg)-1] = 0;
// HERE: These first two can be fixed if the compiler is enhanced to pass
// the original sign information for the base expression.
/* If the element has a MSB that is greater than or equal to the LSB
* and the LSB is greater than zero the compiler created a signed
* expression to normalize the access. This normalization will be
* removed, but we cannot currently determine if the base expression
* started out signed or not so any extra $signed() operators will
* need to be removed manually. */
if ((msb >= lsb) && (lsb > 0) && (sign_type == NEED_SIGNED)) {
fprintf(stderr, "%s: vlog95 sorry: The translation of a select "
"with MSB >= LSB > 0 is not smart enough to remove "
"the extra $signed() operators.\n", msg);
fprintf(stderr, "%*s Any extra $signed() operators "
"will need to be removed manually.\n",
(int)strlen(msg), " ");
vlog_errors += 1;
/* If the element is not a parameter and the LSB > MSB then the cast
* to signed ($signed()) from the normalization process may need to
* be removed. If the select expression is a constant number then
* this is not needed. */
} else if ((lsb > msb) && (ivl_expr_type(sig_expr) != IVL_EX_NUMBER) &&
(ivl_expr_type(sel_expr) != IVL_EX_NUMBER) &&
(sign_type == NEED_SIGNED)) {
fprintf(stderr, "%s: vlog95 sorry: The translation of a select "
"with LSB > MSB is not smart enough to remove "
"the extra $signed() operators.\n", msg);
fprintf(stderr, "%*s Any extra $signed() operators "
"will need to be removed manually.\n",
(int)strlen(msg), " ");
vlog_errors += 1;
/* Parameters are translated with normalization so for some of them
* the -pallowsigned=1 flag is required to get the selection
* expression 100% correct. */
} else if ((! allow_signed) &&
(ivl_expr_type(sig_expr) == IVL_EX_NUMBER)) {
int pmsb, plsb;
ivl_parameter_t param = ivl_expr_parameter(sig_expr);
assert(param);
pmsb = ivl_parameter_msb(param);
plsb = ivl_parameter_lsb(param);
if ((pmsb >= plsb) && (plsb > 0)) {
fprintf(stderr, "%s: vlog95 note: Translating a MSB >= "
"LSB > 0 parameter select requires the "
"-pallowsigned=1 flag.\n", msg);
} else if (plsb > pmsb) {
fprintf(stderr, "%s: vlog95 note: Translating a LSB > "
"MSB parameter select requires the "
"-pallowsigned=1 flag.\n", msg);
}
}
}
static void emit_expr_select(ivl_scope_t scope, ivl_expr_t expr, unsigned wid)
{
ivl_expr_t sel_expr = ivl_expr_oper2(expr);
ivl_expr_t sig_expr = ivl_expr_oper1(expr);
ivl_select_type_t sel_type = ivl_expr_sel_type(expr);
(void)wid; /* Parameter is not used. */
/* If this is a dynamic array or queue select, translate the
* select differently. */
if ((ivl_expr_type(sig_expr) == IVL_EX_SIGNAL) &&
((ivl_signal_data_type(ivl_expr_signal(sig_expr)) == IVL_VT_DARRAY) ||
(ivl_signal_data_type(ivl_expr_signal(sig_expr)) == IVL_VT_QUEUE))) {
assert(sel_expr);
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_expr(scope, sel_expr, 0, 0, 0, 1);
fprintf(vlog_out, "]");
return;
}
if (sel_expr) {
unsigned width = ivl_expr_width(expr);
ivl_expr_type_t type = ivl_expr_type(sig_expr);
assert(width > 0);
/* The compiler uses selects for some shifts. */
if (type != IVL_EX_NUMBER && type != IVL_EX_SIGNAL) {
fprintf(vlog_out, "(" );
emit_select_name(scope, sig_expr);
fprintf(vlog_out, " >> " );
emit_scaled_expr(scope, sel_expr, 1, 0);
fprintf(vlog_out, ")" );
} else {
/* A constant/parameter must be zero based in 1364-1995
* so keep the compiler generated normalization. This
* does not always work for selects before the parameter
* since 1364-1995 does not support signed math. */
int msb = 1;
int lsb = 0;
if (type == IVL_EX_SIGNAL) {
get_sig_msb_lsb(ivl_expr_signal(sig_expr), &msb, &lsb);
}
/* A bit select. */
if (width == 1) {
check_select_signed(sig_expr, sel_expr, msb, lsb);
emit_select_name(scope, sig_expr);
fprintf(vlog_out, "[");
emit_scaled_expr(scope, sel_expr, msb, lsb);
fprintf(vlog_out, "]");
} else if (ivl_expr_type(sel_expr) == IVL_EX_NUMBER) {
/* A constant part select. */
emit_select_name(scope, sig_expr);
emit_scaled_range(scope, sel_expr, width, msb, lsb);
} else if (sel_type == IVL_SEL_OTHER) {
/* A packed array access. */
assert(lsb == 0);
assert(msb >= 0);
emit_expr_packed(scope, sig_expr, sel_expr, width);
} else {
/* An indexed part select. */
check_select_signed(sig_expr, sel_expr, msb, lsb);
emit_expr_ips(scope, sig_expr, sel_expr, sel_type,
width, msb, lsb, type == IVL_EX_NUMBER);
}
}
} else {
// HERE: Should this sign extend if the expression is signed?
unsigned width = ivl_expr_width(expr);
unsigned sig_wid = ivl_expr_width(sig_expr);
emit_expr(scope, sig_expr, sig_wid, 0, 0, 0);
/* Select part of a signal when needed. */
if ((ivl_expr_type(sig_expr) == IVL_EX_SIGNAL) &&
(width < sig_wid)) {
int msb, lsb;
int64_t value;
get_sig_msb_lsb(ivl_expr_signal(sig_expr), &msb, &lsb);
value = lsb;
if (msb >= lsb) value += width - 1;
else value -= width - 1;
fprintf(vlog_out, "[%"PRId64":%u]", value, lsb);
}
}
}
/*
* This routine is used to emit both system and user functions.
*/
static void emit_expr_func(ivl_scope_t scope, ivl_expr_t expr, unsigned wid)
{
unsigned count = ivl_expr_parms(expr);
(void)wid; /* Parameter is not used. */
if (count) {
unsigned idx;
fprintf(vlog_out, "(");
count -= 1;
for (idx = 0; idx < count; idx += 1) {
// HERE: For a user function should the argument width be used here.
emit_expr(scope, ivl_expr_parm(expr, idx), 0, 1, 0, 0);
fprintf(vlog_out, ", ");
}
// HERE: For a user function should the argument width be used here.
emit_expr(scope, ivl_expr_parm(expr, count), 0, 1, 0, 0);
fprintf(vlog_out, ")");
/* User functions without arguments are not supported so a dummy
* argument is added both here and in the definition. */
} else if (ivl_expr_type(expr) == IVL_EX_UFUNC) {
fprintf(vlog_out, "(1'bx)");
}
}
static void emit_expr_signal(ivl_scope_t scope, ivl_expr_t expr, unsigned wid)
{
ivl_signal_t sig = ivl_expr_signal(expr);
(void)wid; /* Parameter is not used. */
emit_scope_call_path(scope, ivl_signal_scope(sig));
emit_id(ivl_signal_basename(sig));
if (ivl_signal_dimensions(sig)) {
int lsb = ivl_signal_array_base(sig);
int msb = lsb + ivl_signal_array_count(sig);
fprintf(vlog_out, "[");
emit_scaled_expr(scope, ivl_expr_oper1(expr), msb, lsb);
fprintf(vlog_out, "]");
}
}
static void emit_expr_ternary(ivl_scope_t scope, ivl_expr_t expr, unsigned wid,
unsigned is_full_prec)
{
ivl_expr_t oper2 = ivl_expr_oper2(expr);
ivl_expr_t oper3 = ivl_expr_oper3(expr);
unsigned can_skip_unsigned = calc_can_skip_unsigned(oper2, oper3);
fprintf(vlog_out, "(");
emit_expr(scope, ivl_expr_oper1(expr), 0, 0, 0, 0);
fprintf(vlog_out, " ? ");
// HERE: Do these two emits need to use get_cast_width() like the binary
// arithmetic operators?
emit_expr(scope, oper2, wid, 0, can_skip_unsigned, is_full_prec);
fprintf(vlog_out, " : ");
emit_expr(scope, oper3, wid, 0, can_skip_unsigned, is_full_prec);
fprintf(vlog_out, ")");
}
static void emit_expr_unary(ivl_scope_t scope, ivl_expr_t expr, unsigned wid,
unsigned is_full_prec)
{
const char *oper = "invalid";
ivl_expr_t oper1 = ivl_expr_oper1(expr);
switch (ivl_expr_opcode(expr)) {
case '-': oper = "-"; break;
case '~': oper = "~"; break;
case '&': oper = "&"; break;
case '|': oper = "|"; break;
case '^': oper = "^"; break;
case 'A': oper = "~&"; break;
case 'N': oper = "~|"; break;
case 'X': oper = "~^"; break;
case '!': oper = "!"; break;
}
switch (ivl_expr_opcode(expr)) {
case '-':
case '~':
fprintf(vlog_out, "(%s", oper);
emit_expr(scope, oper1, wid, 0, 0, is_full_prec);
fprintf(vlog_out, ")");
break;
case '&':
case '|':
case '^':
case 'A':
case 'N':
case 'X':
case '!':
fprintf(vlog_out, "(%s", oper);
emit_expr(scope, oper1, 0, 0, 0, 0);
fprintf(vlog_out, ")");
break;
case '2':
case 'v':
case 'r':
/* A cast is a noop. */
emit_expr(scope, oper1, 0, 0, 0, 0);
break;
case 'I':
fprintf(vlog_out, "(++");
emit_expr(scope, oper1, wid, 0, 0, is_full_prec);
fprintf(vlog_out, ")");
fprintf(stderr, "%s:%u: vlog95 sorry: Pre-increment "
"operator is not currently translated.\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr));
vlog_errors += 1;
break;
case 'i':
fprintf(vlog_out, "(");
emit_expr(scope, oper1, wid, 0, 0, is_full_prec);
fprintf(vlog_out, "++)");
fprintf(stderr, "%s:%u: vlog95 sorry: Post-increment "
"operator is not currently translated.\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr));
vlog_errors += 1;
break;
case 'D':
fprintf(vlog_out, "(--");
emit_expr(scope, oper1, wid, 0, 0, is_full_prec);
fprintf(vlog_out, ")");
fprintf(stderr, "%s:%u: vlog95 sorry: Pre-decrement "
"operator is not currently translated.\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr));
vlog_errors += 1;
break;
case 'd':
fprintf(vlog_out, "(");
emit_expr(scope, oper1, wid, 0, 0, is_full_prec);
fprintf(vlog_out, "--)");
fprintf(stderr, "%s:%u: vlog95 sorry: Post-decrement "
"operator is not currently translated.\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr));
vlog_errors += 1;
break;
/* Convert the Verilog-A abs() function. */
case 'm':
if (ivl_expr_value(expr) == IVL_VT_REAL) {
/* For a real expression use the $abs() function. */
fprintf(vlog_out, "$abs(");
emit_expr(scope, oper1, wid, 0, 0, is_full_prec);
fprintf(vlog_out, ")");
} else {
/* This only works when the argument has no side effect. */
fprintf(vlog_out, "((");
emit_expr(scope, oper1, wid, 0, 0, is_full_prec);
fprintf(vlog_out, ") > 0 ? (");
emit_expr(scope, oper1, wid, 0, 0, is_full_prec);
fprintf(vlog_out, ") : -(");
emit_expr(scope, oper1, wid, 0, 0, is_full_prec);
fprintf(vlog_out, "))");
}
break;
default:
fprintf(vlog_out, "<unknown>");
emit_expr(scope, oper1, wid, 0, 0, 0);
fprintf(stderr, "%s:%u: vlog95 error: Unknown unary "
"operator (%c).\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr),
ivl_expr_opcode(expr));
vlog_errors += 1;
break;
}
}
void emit_expr(ivl_scope_t scope, ivl_expr_t expr, unsigned wid,
unsigned is_lval_width, unsigned can_skip_unsigned,
unsigned is_full_prec)
{
expr_sign_t sign_type;
/* If the width is from an L-value (assignment) then the actual
* expression width can be larger. */
if (is_lval_width) {
unsigned expr_wid = ivl_expr_width(expr);
if (wid < expr_wid) wid = expr_wid;
}
/* In a self-determined context the expression set the width. */
if (! wid) wid = ivl_expr_width(expr);
sign_type = expr_get_sign_type(expr, wid, can_skip_unsigned,
is_full_prec);
/* Check to see if a $signed() or $unsigned() needs to be emitted
* before the expression. */
if (sign_type == NEED_SIGNED) {
fprintf(vlog_out, "$signed(");
if (! allow_signed) {
fprintf(stderr, "%s:%u: vlog95 error: $signed() is not "
"supported.\n",
ivl_expr_file(expr), ivl_expr_lineno(expr));
vlog_errors += 1;
}
/* A $signed() creates a self-determined context. */
wid = 0;
/* It also clears the full precision flag. */
is_full_prec = 0;
}
if (sign_type == NEED_UNSIGNED) {
fprintf(vlog_out, "$unsigned(");
if (! allow_signed) {
fprintf(stderr, "%s:%u: vlog95 error: $unsigned() is not "
"supported.\n",
ivl_expr_file(expr), ivl_expr_lineno(expr));
vlog_errors += 1;
}
/* A $unsigned() creates a self-determined context. */
wid = 0;
/* It also clears the full precision flag. */
is_full_prec = 0;
}
/* Emit the expression. */
switch (ivl_expr_type(expr)) {
case IVL_EX_ARRAY:
emit_expr_array(scope, expr, wid);
break;
case IVL_EX_ARRAY_PATTERN:
fprintf(vlog_out, "<array pattern>");
fprintf(stderr, "%s:%u: vlog95 error: Array pattern expressions "
"are not supported.\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr));
vlog_errors += 1;
break;
case IVL_EX_BINARY:
emit_expr_binary(scope, expr, wid, is_full_prec);
break;
case IVL_EX_CONCAT:
emit_expr_concat(scope, expr, wid);
break;
case IVL_EX_DELAY:
emit_expr_delay(scope, expr, wid);
break;
case IVL_EX_ENUMTYPE:
fprintf(vlog_out, "<enum>");
fprintf(stderr, "%s:%u: vlog95 error: Enum expressions "
"are not supported.\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr));
vlog_errors += 1;
break;
case IVL_EX_EVENT:
emit_expr_event(scope, expr, wid);
break;
case IVL_EX_NEW:
fprintf(vlog_out, "<new>");
fprintf(stderr, "%s:%u: vlog95 error: New operator "
"is not supported.\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr));
vlog_errors += 1;
break;
case IVL_EX_NULL:
fprintf(vlog_out, "<null>");
fprintf(stderr, "%s:%u: vlog95 error: Null operator "
"is not supported.\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr));
vlog_errors += 1;
break;
case IVL_EX_NUMBER:
emit_expr_number(scope, expr, wid);
break;
case IVL_EX_PROPERTY:
emit_class_property(scope, expr, wid);
break;
case IVL_EX_REALNUM:
emit_expr_real_number(scope, expr, wid);
break;
case IVL_EX_SCOPE:
emit_expr_scope(scope, expr, wid);
break;
case IVL_EX_SELECT:
emit_expr_select(scope, expr, wid);
break;
case IVL_EX_SFUNC:
fprintf(vlog_out, "%s", ivl_expr_name(expr));
emit_expr_func(scope, expr, wid);
break;
case IVL_EX_SHALLOWCOPY:
fprintf(vlog_out, "<new> ");
emit_expr(scope, ivl_expr_oper2(expr), wid, 0, 0, 0);
fprintf(stderr, "%s:%u: vlog95 error: New operator "
"is not supported.\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr));
vlog_errors += 1;
break;
case IVL_EX_SIGNAL:
emit_expr_signal(scope, expr, wid);
break;
case IVL_EX_STRING:
emit_string(ivl_expr_string(expr));
break;
case IVL_EX_TERNARY:
emit_expr_ternary(scope, expr, wid, is_full_prec);
break;
case IVL_EX_UFUNC:
emit_scope_path(scope, ivl_expr_def(expr));
emit_expr_func(scope, expr, wid);
break;
case IVL_EX_UNARY:
emit_expr_unary(scope, expr, wid, is_full_prec);
break;
default:
fprintf(vlog_out, "<unknown>");
fprintf(stderr, "%s:%u: vlog95 error: Unknown expression "
"type (%d).\n",
ivl_expr_file(expr),
ivl_expr_lineno(expr),
(int)ivl_expr_type(expr));
vlog_errors += 1;
break;
}
/* Close the $signed() or $unsigned() if need. */
if (sign_type != NO_SIGN) fprintf(vlog_out, ")");
}