iverilog/vvp/vpi_priv.cc

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/*
* Copyright (c) 2001 Stephen Williams (steve@icarus.com)
*
* This source code is free software; you can redistribute it
* and/or modify it in source code form 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CVS_IDENT
#ident "$Id: vpi_priv.cc,v 1.46 2004/05/19 03:26:24 steve Exp $"
#endif
# include "vpi_priv.h"
# include "schedule.h"
# include <stdio.h>
# include <stdarg.h>
# include <string.h>
# include <assert.h>
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#ifdef HAVE_MALLOC_H
# include <malloc.h>
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#endif
# include <stdlib.h>
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# include <math.h>
vpi_mode_t vpi_mode_flag = VPI_MODE_NONE;
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FILE*vpi_trace = 0;
static s_vpi_vlog_info vpi_vlog_info;
static s_vpi_error_info vpip_last_error = { 0, 0, 0, 0, 0, 0, 0 };
/*
* The vpip_string function creates a constant string from the pass
* input. This constant string is permanently allocate from an
* efficient string buffer store.
*/
struct vpip_string_chunk {
struct vpip_string_chunk*next;
char data[64*1024 - sizeof (struct vpip_string_chunk*)];
};
const char *vpip_string(const char*str)
{
static vpip_string_chunk first_chunk = {0, {0}};
static vpip_string_chunk*chunk_list = &first_chunk;
static unsigned chunk_fill = 0;
unsigned len = strlen(str);
assert( (len+1) <= sizeof chunk_list->data );
if ( (len+1) > (sizeof chunk_list->data - chunk_fill) ) {
vpip_string_chunk*tmp = new vpip_string_chunk;
tmp->next = chunk_list;
chunk_list = tmp;
chunk_fill = 0;
}
char*res = chunk_list->data + chunk_fill;
chunk_fill += len + 1;
strcpy(res, str);
return res;
}
static unsigned hash_string(const char*text)
{
unsigned h = 0;
while (*text) {
h = (h << 4) ^ (h >> 28) ^ *text;
text += 1;
}
return h;
}
const char* vpip_name_string(const char*text)
{
const unsigned HASH_SIZE = 4096;
static const char*hash_table[HASH_SIZE] = {0};
unsigned hash_value = hash_string(text) % HASH_SIZE;
/* If we easily find the string in the hash table, then return
that and be done. */
if (hash_table[hash_value]
&& (strcmp(hash_table[hash_value], text) == 0)) {
return hash_table[hash_value];
}
/* The existing hash entry is not a match. Replace it with the
newly allocated value, and return the new pointer as the
result to the add. */
const char*res = vpip_string(text);
hash_table[hash_value] = res;
return res;
}
PLI_INT32 vpi_chk_error(p_vpi_error_info info)
{
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if (vpip_last_error.state == 0)
return 0;
info->state = vpip_last_error.state;
info->level = vpip_last_error.level;
info->message = vpip_last_error.message;
info->product = vpi_vlog_info.product;
info->code = "";
info->file = 0;
info->line = 0;
return info->level;
}
/*
* When a task is called, this value is set so that vpi_handle can
* fathom the vpi_handle(vpiSysTfCall,0) function.
*/
struct __vpiSysTaskCall*vpip_cur_task = 0;
PLI_INT32 vpi_free_object(vpiHandle ref)
{
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int rtn;
if (vpi_trace) {
fprintf(vpi_trace, "vpi_free_object(%p)", ref);
fflush(vpi_trace);
}
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assert(ref);
if (ref->vpi_type->vpi_free_object_ == 0)
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rtn = 1;
else
rtn = ref->vpi_type->vpi_free_object_(ref);
if (vpi_trace)
fprintf(vpi_trace, " --> %d\n", rtn);
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return rtn;
}
static int vpip_get_global(int property)
{
switch (property) {
case vpiTimePrecision:
return vpip_get_time_precision();
default:
fprintf(stderr, "vpi error: bad global property: %d\n", property);
assert(0);
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return vpiUndefined;
}
}
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static const char* vpi_property_str(PLI_INT32 code)
{
static char buf[32];
switch (code) {
case vpiConstType:
return "vpiConstType";
case vpiName:
return "vpiName";
case vpiFullName:
return "vpiFullName";
case vpiTimeUnit:
return "vpiTimeUnit";
default:
sprintf(buf, "%d", code);
}
return buf;
}
static const char* vpi_type_values(PLI_INT32 code)
{
static char buf[32];
switch (code) {
case vpiConstant:
return "vpiConstant";
case vpiModule:
return "vpiModule";
case vpiNet:
return "vpiNet";
case vpiReg:
return "vpiReg";
default:
sprintf(buf, "%d", code);
}
return buf;
}
PLI_INT32 vpi_get(int property, vpiHandle ref)
{
if (ref == 0)
return vpip_get_global(property);
if (property == vpiType) {
if (vpi_trace) {
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fprintf(vpi_trace, "vpi_get(vpiType, %p) --> %s\n",
ref, vpi_type_values(ref->vpi_type->type_code));
}
struct __vpiSignal*rfp = (struct __vpiSignal*)ref;
if (ref->vpi_type->type_code == vpiReg && rfp->isint_)
return vpiIntegerVar;
else
return ref->vpi_type->type_code;
}
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if (ref->vpi_type->vpi_get_ == 0) {
if (vpi_trace) {
fprintf(vpi_trace, "vpi_get(%s, %p) --X\n",
vpi_property_str(property), ref);
}
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return vpiUndefined;
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}
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int res = (ref->vpi_type->vpi_get_)(property, ref);
if (vpi_trace) {
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fprintf(vpi_trace, "vpi_get(%s, %p) --> %d\n",
vpi_property_str(property), ref, res);
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}
return res;
}
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char* vpi_get_str(PLI_INT32 property, vpiHandle ref)
{
if (ref == 0) {
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fprintf(stderr, "vpi error: vpi_get_str(%s, 0) called "
"with null vpiHandle.\n", vpi_property_str(property));
return 0;
}
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assert(ref);
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if (ref->vpi_type->vpi_get_str_ == 0) {
if (vpi_trace) {
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fprintf(vpi_trace, "vpi_get_str(%s, %p) --X\n",
vpi_property_str(property), ref);
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}
return 0;
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}
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char*res = (char*)(ref->vpi_type->vpi_get_str_)(property, ref);
if (vpi_trace) {
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fprintf(vpi_trace, "vpi_get_str(%s, %p) --> %s\n",
vpi_property_str(property), ref, res);
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}
return res;
}
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int vpip_time_units_from_handle(vpiHandle obj)
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{
struct __vpiSysTaskCall*task;
struct __vpiScope*scope;
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struct __vpiSignal*signal;
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if (obj == 0)
return vpip_get_time_precision();
switch (obj->vpi_type->type_code) {
case vpiSysTaskCall:
task = (struct __vpiSysTaskCall*)obj;
return task->scope->time_units;
case vpiModule:
scope = (struct __vpiScope*)obj;
return scope->time_units;
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case vpiNet:
case vpiReg:
signal = (struct __vpiSignal*)obj;
return signal->scope->time_units;
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default:
fprintf(stderr, "ERROR: vpi_get_time called with object "
"handle type=%u\n", obj->vpi_type->type_code);
assert(0);
return 0;
}
}
void vpi_get_time(vpiHandle obj, s_vpi_time*vp)
{
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int units;
vvp_time64_t time;
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assert(vp);
time = schedule_simtime();
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switch (vp->type) {
case vpiSimTime:
vp->high = (time >> 32) & 0xffffffff;
vp->low = time & 0xffffffff;
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break;
case vpiScaledRealTime:
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units = vpip_time_units_from_handle(obj);
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vp->real = pow(10, vpip_get_time_precision() - units);
vp->real *= time;
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break;
default:
fprintf(stderr, "vpi_get_time: unknown type: %d\n", vp->type);
assert(0);
break;
}
}
PLI_INT32 vpi_get_vlog_info(p_vpi_vlog_info vlog_info_p)
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{
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if (vlog_info_p != 0) {
*vlog_info_p = vpi_vlog_info;
return 1;
} else {
return 0;
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}
}
void vpi_set_vlog_info(int argc, char** argv)
{
vpi_vlog_info.product = "Icarus Verilog";
vpi_vlog_info.version = "$Name: $";
vpi_vlog_info.argc = argc;
vpi_vlog_info.argv = argv;
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static char trace_buf[1024];
if (const char*path = getenv("VPI_TRACE")) {
if (!strcmp(path,"-"))
vpi_trace = stdout;
else {
vpi_trace = fopen(path, "w");
if (!vpi_trace) {
perror(path);
exit(1);
}
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setvbuf(vpi_trace, trace_buf, _IOLBF, sizeof(trace_buf));
}
}
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}
void vpi_get_value(vpiHandle expr, s_vpi_value*vp)
{
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assert(expr);
assert(vp);
if (expr->vpi_type->vpi_get_value_) {
(expr->vpi_type->vpi_get_value_)(expr, vp);
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if (vpi_trace) switch (vp->format) {
case vpiStringVal:
fprintf(vpi_trace,"vpi_get_value(%p=<%d>) -> string=\"%s\"\n",
expr, expr->vpi_type->type_code, vp->value.str);
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break;
case vpiBinStrVal:
fprintf(vpi_trace, "vpi_get_value(<%d>...) -> binstr=%s\n",
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expr->vpi_type->type_code, vp->value.str);
break;
case vpiIntVal:
fprintf(vpi_trace, "vpi_get_value(<%d>...) -> int=%d\n",
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expr->vpi_type->type_code, vp->value.integer);
break;
default:
fprintf(vpi_trace, "vpi_get_value(<%d>...) -> <%d>=?\n",
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expr->vpi_type->type_code, vp->format);
}
return;
}
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if (vpi_trace) {
fprintf(vpi_trace, "vpi_get_value(<%d>...) -> <suppress>\n",
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expr->vpi_type->type_code);
}
vp->format = vpiSuppressVal;
}
struct vpip_put_value_event : vvp_gen_event_s {
vpiHandle handle;
s_vpi_value value;
};
static void vpip_put_value_callback(vvp_gen_event_t eobj, unsigned char)
{
vpip_put_value_event*put = (vpip_put_value_event*)eobj;
put->handle->vpi_type->vpi_put_value_ (put->handle, &put->value);
}
vpiHandle vpi_put_value(vpiHandle obj, s_vpi_value*vp,
s_vpi_time*when, PLI_INT32 flags)
{
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assert(obj);
if (obj->vpi_type->vpi_put_value_ == 0)
return 0;
if (flags != vpiNoDelay) {
vvp_time64_t dly;
switch (when->type) {
case vpiScaledRealTime:
dly = (vvp_time64_t)(when->real *
(pow(10,
vpip_time_units_from_handle(obj) -
vpip_get_time_precision())));
break;
case vpiSimTime:
dly = vpip_timestruct_to_time(when);
break;
default:
dly = 0;
break;
}
vpip_put_value_event*put = new vpip_put_value_event;
put->handle = obj;
put->value = *vp;
put->run = &vpip_put_value_callback;
schedule_generic(put, 0, dly, false);
return 0;
}
(obj->vpi_type->vpi_put_value_)(obj, vp);
return 0;
}
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vpiHandle vpi_handle(PLI_INT32 type, vpiHandle ref)
{
if (type == vpiSysTfCall) {
assert(ref == 0);
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if (vpi_trace) {
fprintf(vpi_trace, "vpi_handle(vpiSysTfCall, 0) "
"-> %p (%s)\n", &vpip_cur_task->base,
vpip_cur_task->defn->info.tfname);
}
return &vpip_cur_task->base;
}
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if (ref == 0) {
fprintf(stderr, "internal error: vpi_handle(type=%d, ref=0)\n",
type);
}
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assert(ref);
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if (ref->vpi_type->handle_ == 0) {
if (vpi_trace) {
fprintf(vpi_trace, "vpi_handle(%d, %p) -X\n",
type, ref);
}
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return 0;
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}
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assert(ref->vpi_type->handle_);
vpiHandle res = (ref->vpi_type->handle_)(type, ref);
if (vpi_trace) {
fprintf(vpi_trace, "vpi_handle(%d, %p) -> %p\n",
type, ref, res);
}
return res;
}
/*
* This function asks the object to return an iterator for
* the specified reference. It is up to the iterate_ method to
* allocate a properly formed iterator.
*/
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static vpiHandle vpi_iterate_global(int type)
{
switch (type) {
case vpiModule:
return vpip_make_root_iterator();
}
return 0;
}
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vpiHandle vpi_iterate(PLI_INT32 type, vpiHandle ref)
{
vpiHandle rtn = 0;
assert(vpi_mode_flag != VPI_MODE_NONE);
if (vpi_mode_flag == VPI_MODE_REGISTER) {
fprintf(stderr, "vpi error: vpi_iterate called during "
"vpi_register_systf. You can't do that!\n");
return 0;
}
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if (ref == 0)
rtn = vpi_iterate_global(type);
else if (ref->vpi_type->iterate_)
rtn = (ref->vpi_type->iterate_)(type, ref);
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if (vpi_trace) {
fprintf(vpi_trace, "vpi_iterate(%d, %p) ->%s\n",
type, ref, rtn ? "" : " (null)");
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}
return rtn;
}
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vpiHandle vpi_handle_by_index(vpiHandle ref, PLI_INT32 idx)
{
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assert(ref);
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if (ref->vpi_type->index_ == 0)
return 0;
assert(ref->vpi_type->index_);
return (ref->vpi_type->index_)(ref, idx);
}
static vpiHandle find_name(const char *name, vpiHandle handle)
{
vpiHandle rtn = 0;
struct __vpiScope*ref = (struct __vpiScope*)handle;
/* check module names */
if (!strcmp(name, vpi_get_str(vpiName, handle)))
rtn = handle;
/* brute force search for the name in all objects in this scope */
for (unsigned i = 0 ; i < ref->nintern ; i += 1) {
char *nm = vpi_get_str(vpiName, ref->intern[i]);
if (!strcmp(name, nm)) {
rtn = ref->intern[i];
break;
} else if (vpi_get(vpiType, ref->intern[i]) == vpiMemory) {
/* We need to iterate on the words */
vpiHandle word_i, word_h;
word_i = vpi_iterate(vpiMemoryWord, ref->intern[i]);
while (word_i && (word_h = vpi_scan(word_i))) {
nm = vpi_get_str(vpiName, word_h);
if (!strcmp(name, nm)) {
rtn = word_h;
break;
}
}
}
/* found it yet? */
if (rtn) break;
}
return rtn;
}
static vpiHandle find_scope(const char *name, vpiHandle handle, int depth)
{
vpiHandle iter, hand, rtn = 0;
iter = !handle ? vpi_iterate(vpiModule, NULL) :
vpi_iterate(vpiInternalScope, handle);
while (iter && (hand = vpi_scan(iter))) {
char *nm = vpi_get_str(vpiName, hand);
int len = strlen(nm);
const char *cp = name + len; /* hier separator */
if (!handle && !strcmp(name, nm)) {
/* root module */
rtn = hand;
} else if (!strncmp(name, nm, len) && *(cp) == '.')
/* recurse deeper */
rtn = find_scope(cp+1, hand, depth + 1);
/* found it yet ? */
if (rtn) break;
}
/* matched up to here */
if (!rtn) rtn = handle;
return rtn;
}
vpiHandle vpi_handle_by_name(const char *name, vpiHandle scope)
{
vpiHandle hand;
const char *nm, *cp;
int len;
if (vpi_trace) {
fprintf(vpi_trace, "vpi_handle_by_name(%s, %p) -->\n",
name, scope);
}
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/* If scope provided, look in corresponding module; otherwise
* traverse the hierarchy specified in name to find the leaf module
* and try finding it there.
*/
if (scope)
hand = vpi_handle(vpiModule, scope);
else
hand = find_scope(name, NULL, 0);
if (hand) {
/* remove hierarchical portion of name */
nm = vpi_get_str(vpiFullName, hand);
len = strlen(nm);
cp = name + len;
if (!strncmp(name, nm, len) && *cp == '.') name = cp + 1;
/* Ok, time to burn some cycles */
vpiHandle out = find_name(name, hand);
return out;
}
return 0;
}
extern "C" PLI_INT32 vpi_vprintf(const char*fmt, va_list ap)
{
return vpi_mcd_vprintf(1, fmt, ap);
}
extern "C" PLI_INT32 vpi_printf(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
int r = vpi_mcd_vprintf(1, fmt, ap);
va_end(ap);
return r;
}
extern "C" PLI_INT32 vpi_flush(void)
{
return vpi_mcd_flush(1);
}
extern "C" void vpi_sim_vcontrol(int operation, va_list ap)
{
switch (operation) {
case vpiFinish:
schedule_finish(0);
break;
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case vpiStop:
schedule_stop(0);
break;
default:
assert(0);
}
}
extern "C" void vpi_sim_control(PLI_INT32 operation, ...)
{
va_list ap;
va_start(ap, operation);
vpi_sim_vcontrol(operation, ap);
va_end(ap);
}
extern "C" void vpi_control(PLI_INT32 operation, ...)
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{
va_list ap;
va_start(ap, operation);
vpi_sim_vcontrol(operation, ap);
va_end(ap);
}
/*
* $Log: vpi_priv.cc,v $
* Revision 1.46 2004/05/19 03:26:24 steve
* Support delayed/non-blocking assignment to reals and others.
*
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* Revision 1.45 2004/02/18 17:52:00 steve
* PRototypes match the standard.
*
* Revision 1.44 2004/02/18 02:51:59 steve
* Fix type mismatches of various VPI functions.
*
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* Revision 1.43 2003/06/25 04:04:19 steve
* Fix mingw portability problems.
*
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* Revision 1.42 2003/06/22 04:19:26 steve
* vpi_handle diagnostic message.
*
* Revision 1.41 2003/06/17 16:55:08 steve
* 1) setlinebuf() for vpi_trace
* 2) Addes error checks for trace file opens
* 3) removes now extraneous flushes
* 4) fixes acc_next() bug
*
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* Revision 1.40 2003/05/30 04:08:28 steve
* vpi_trace of vpi_free_object.
*
* Revision 1.39 2003/05/15 16:51:09 steve
* Arrange for mcd id=00_00_00_01 to go to stdout
* as well as a user specified log file, set log
* file to buffer lines.
*
* Add vpi_flush function, and clear up some cunfused
* return codes from other vpi functions.
*
* Adjust $display and vcd/lxt messages to use the
* standard output/log file.
*
* Revision 1.38 2003/05/15 01:24:46 steve
* Return all 64bits of time in vpi_get_time.
*
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* Revision 1.37 2003/05/02 04:29:57 steve
* Add put_value with transport delay.
*
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* Revision 1.36 2003/04/27 04:19:24 steve
* Support vpiScaledRealTime.
*
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* Revision 1.35 2003/03/14 05:02:34 steve
* More detail in vpi tracing.
*
* Revision 1.34 2003/03/13 04:34:18 steve
* Add VPI_TRACE tracing of VPI calls.
* vpi_handle_by_name takes a const char*.
*
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* Revision 1.33 2003/03/12 02:50:32 steve
* Add VPI tracing.
*
* Revision 1.32 2003/03/06 04:32:00 steve
* Use hashed name strings for identifiers.
*
2003-02-21 04:40:35 +01:00
* Revision 1.31 2003/02/21 03:40:35 steve
* Add vpiStop and interactive mode.
*
2003-02-10 00:33:26 +01:00
* Revision 1.30 2003/02/09 23:33:26 steve
* Spelling fixes.
*
* Revision 1.29 2003/02/02 01:40:24 steve
* Five vpi_free_object a default behavior.
*
2003-01-10 20:02:21 +01:00
* Revision 1.28 2003/01/10 19:02:21 steve
* Add missing vpi entry points.
*
* Revision 1.27 2003/01/10 03:06:32 steve
* Remove vpithunk, and move libvpi to vvp directory.
*
* Revision 1.26 2002/12/21 00:55:58 steve
* The $time system task returns the integer time
* scaled to the local units. Change the internal
* implementation of vpiSystemTime the $time functions
* to properly account for this. Also add $simtime
* to get the simulation time.
*
* Revision 1.25 2002/12/11 23:55:22 steve
* Add vpi_handle_by_name to the VPI interface,
* and bump the vpithunk magic number.
*
2002-08-24 07:02:58 +02:00
* Revision 1.24 2002/08/24 05:02:58 steve
* Fix = vs == error.
*
* Revision 1.23 2002/08/12 01:35:09 steve
* conditional ident string using autoconfig.
*
* Revision 1.22 2002/07/19 01:57:26 steve
* Add vpi_chk_error and vpi_control functions.
*
2002-07-19 03:12:50 +02:00
* Revision 1.21 2002/07/19 01:12:50 steve
* vpi_iterate returns 0 on error.
*/