iverilog/vvp/vthread.cc

1836 lines
43 KiB
C++

/*
* 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
*/
#if !defined(WINNT)
#ident "$Id: vthread.cc,v 1.64 2001/11/06 03:07:22 steve Exp $"
#endif
# include "vthread.h"
# include "codes.h"
# include "debug.h"
# include "schedule.h"
# include "functor.h"
# include "event.h"
# include "vpi_priv.h"
#ifdef HAVE_MALLOC_H
# include <malloc.h>
#endif
# include <stdlib.h>
# include <string.h>
# include <assert.h>
#include <stdio.h>
/*
* This vhtread_s structure describes all there is to know about a
* thread, including its program counter, all the private bits it
* holds, and its place in other lists.
*
*
* ** Notes On The Interactions of %fork/%join/%end:
*
* The %fork instruction creates a new thread and pushes that onto the
* stack of children for the thread. This new thread, then, becomes
* the new direct descendent of the thread. This new thread is
* therefore also the first thread to be reaped when the parent does a
* %join.
*
* It is a programming error for a thread that created threads to not
* %join as many as it created before it %ends. The linear stack for
* tracking thread relationships will create a mess otherwise. For
* example, if A creates B then C, the stack is:
*
* A --> C --> B
*
* If C then %forks X, the stack is:
*
* A --> C --> X --> B
*
* If C %ends without a join, then the stack is:
*
* A --> C(zombie) --> X --> B
*
* If A then executes 2 %joins, it will read C and X (when it ends)
* leaving B in purgatory. What's worse, A will block on the schedules
* of X and C instead of C and B, possibly creating incorrect timing.
*
* The schedule_parent_on_end flag is used by threads to tell their
* children that they are waiting for it to end. It is set by a %join
* instruction if the child is not already done. The thread that
* executes a %join instruction sets the flag in its child.
*
* The i_have_ended flag, on the other hand, is used by threads to
* tell their parents that they are already dead. A thread that
* executes %end will set its own i_have_ended flag and let its parent
* reap it when the parent does the %join. If a thread has its
* schedule_parent_on_end flag set already when it %ends, then it
* reaps itself and simply schedules its parent. If a child has its
* i_have_ended flag set when a thread executes %join, then it is free
* to reap the child immediately.
*/
struct vthread_s {
/* This is the program counter. */
unsigned long pc;
/* These hold the private thread bits. */
unsigned char *bits;
long index[4];
unsigned nbits :16;
/* My parent sets this when it wants me to wake it up. */
unsigned schedule_parent_on_end :1;
unsigned i_have_ended :1;
unsigned waiting_for_event :1;
unsigned is_scheduled :1;
/* This points to the sole child of the thread. */
struct vthread_s*child;
/* This points to my parent, if I have one. */
struct vthread_s*parent;
/* This is used for keeping wait queues. */
struct vthread_s*wait_next;
/* These are used to keep the thread in a scope. */
struct vthread_s*scope_next, *scope_prev;
};
static void thr_check_addr(struct vthread_s*thr, unsigned addr)
{
if (addr < thr->nbits)
return;
assert(addr < 0x10000);
while (thr->nbits <= addr) {
thr->bits = (unsigned char*)realloc(thr->bits, thr->nbits/4 + 16);
memset(thr->bits + thr->nbits/4, 0xaa, 16);
thr->nbits += 16*4;
}
}
static inline unsigned thr_get_bit(struct vthread_s*thr, unsigned addr)
{
assert(addr < thr->nbits);
unsigned idx = addr % 4;
addr /= 4;
return (thr->bits[addr] >> (idx*2)) & 3;
}
static inline void thr_put_bit(struct vthread_s*thr,
unsigned addr, unsigned val)
{
thr_check_addr(thr, addr);
unsigned idx = addr % 4;
addr /= 4;
unsigned mask = 3 << (idx*2);
thr->bits[addr] = (thr->bits[addr] & ~mask) | (val << (idx*2));
}
unsigned vthread_get_bit(struct vthread_s*thr, unsigned addr)
{
return thr_get_bit(thr, addr);
}
void vthread_put_bit(struct vthread_s*thr, unsigned addr, unsigned bit)
{
thr_put_bit(thr, addr, bit);
}
# define CPU_BITS (8*sizeof(unsigned long))
# define TOP_BIT (1UL << (CPU_BITS-1))
static unsigned long* vector_to_array(struct vthread_s*thr,
unsigned addr, unsigned wid)
{
unsigned awid = (wid + CPU_BITS - 1) / (8*sizeof(unsigned long));
unsigned long*val = new unsigned long[awid];
for (unsigned idx = 0 ; idx < awid ; idx += 1)
val[idx] = 0;
for (unsigned idx = 0 ; idx < wid ; idx += 1) {
unsigned long bit = thr_get_bit(thr, addr);
if (bit & 2)
goto x_out;
val[idx/CPU_BITS] |= bit << (idx % CPU_BITS);
if (addr >= 4)
addr += 1;
}
return val;
x_out:
delete[]val;
return 0;
}
/*
* Create a new thread with the given start address.
*/
vthread_t vthread_new(unsigned long pc, struct __vpiScope*scope)
{
vthread_t thr = new struct vthread_s;
thr->pc = pc;
thr->bits = (unsigned char*)malloc(16);
thr->nbits = 16*4;
thr->child = 0;
thr->parent = 0;
thr->wait_next = 0;
/* If the target scope never held a thread, then create a
header cell for it. This is a stub to make circular lists
easier to work with. */
if (scope->threads == 0) {
scope->threads = new struct vthread_s;
scope->threads->pc = 0;
scope->threads->bits = 0;
scope->threads->nbits = 0;
scope->threads->child = 0;
scope->threads->parent = 0;
scope->threads->scope_prev = scope->threads;
scope->threads->scope_next = scope->threads;
}
{ vthread_t tmp = scope->threads;
thr->scope_next = tmp->scope_next;
thr->scope_prev = tmp;
thr->scope_next->scope_prev = thr;
thr->scope_prev->scope_next = thr;
}
thr->schedule_parent_on_end = 0;
thr->is_scheduled = 0;
thr->i_have_ended = 0;
thr->waiting_for_event = 0;
thr->is_scheduled = 0;
thr_put_bit(thr, 0, 0);
thr_put_bit(thr, 1, 1);
thr_put_bit(thr, 2, 2);
thr_put_bit(thr, 3, 3);
return thr;
}
/*
* Reaping pulls the thread out of the stack of threads. If I have a
* child, then hand it over to my parent.
*/
static void vthread_reap(vthread_t thr)
{
assert(thr->wait_next == 0);
free(thr->bits);
thr->bits = 0;
if (thr->child)
thr->child->parent = thr->parent;
if (thr->parent)
thr->parent->child = thr->child;
thr->child = 0;
thr->parent = 0;
thr->scope_next->scope_prev = thr->scope_prev;
thr->scope_prev->scope_next = thr->scope_next;
thr->pc = 0;
/* If this thread is not scheduled, then is it safe to delete
it now. Otherwise, let the schedule event (which will
execute the thread at of_ZOMBIE) delete the object. */
if (thr->is_scheduled == 0)
delete thr;
}
void vthread_mark_scheduled(vthread_t thr)
{
assert(thr->is_scheduled == 0);
thr->is_scheduled = 1;
}
/*
* This function runs a thread by fetching an instruction,
* incrementing the PC, and executing the instruction.
*/
void vthread_run(vthread_t thr)
{
assert(thr->is_scheduled);
thr->is_scheduled = 0;
for (;;) {
vvp_code_t cp = codespace_index(thr->pc);
thr->pc += 1;
assert(cp->opcode);
/* Run the opcode implementation. If the execution of
the opcode returns false, then the thread is meant to
be paused, so break out of the loop. */
bool rc = (cp->opcode)(thr, cp);
if (rc == false)
return;
}
}
/*
* This is called by an event functor to wake up all the threads on
* its list. I in fact created that list in the %wait instruction, and
* I also am certain that the waiting_for_event flag is set.
*/
void vthread_schedule_list(vthread_t thr)
{
while (thr) {
vthread_t tmp = thr;
thr = thr->wait_next;
assert(tmp->waiting_for_event);
tmp->waiting_for_event = 0;
tmp->wait_next = 0;
schedule_vthread(tmp, 0);
}
}
bool of_AND(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lb = thr_get_bit(thr, idx1);
unsigned rb = thr_get_bit(thr, idx2);
if ((lb == 0) || (rb == 0)) {
thr_put_bit(thr, idx1, 0);
} else if ((lb == 1) && (rb == 1)) {
thr_put_bit(thr, idx1, 1);
} else {
thr_put_bit(thr, idx1, 2);
}
idx1 += 1;
if (idx2 >= 4)
idx2 += 1;
}
return true;
}
bool of_ADD(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned long*lva = vector_to_array(thr, cp->bit_idx[0], cp->number);
unsigned long*lvb = vector_to_array(thr, cp->bit_idx[1], cp->number);
if (lva == 0 || lvb == 0)
goto x_out;
unsigned long carry;
carry = 0;
for (unsigned idx = 0 ; (idx*CPU_BITS) < cp->number ; idx += 1) {
unsigned long tmp = lvb[idx] + carry;
unsigned long sum = lva[idx] + tmp;
carry = 0;
if (tmp < lvb[idx])
carry = 1;
if (sum < tmp)
carry = 1;
if (sum < lva[idx])
carry = 1;
lva[idx] = sum;
}
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned bit = lva[idx/CPU_BITS] >> (idx % CPU_BITS);
thr_put_bit(thr, cp->bit_idx[0]+idx, (bit&1) ? 1 : 0);
}
delete[]lva;
delete[]lvb;
return true;
x_out:
delete[]lva;
delete[]lvb;
for (unsigned idx = 0 ; idx < cp->number ; idx += 1)
thr_put_bit(thr, cp->bit_idx[0]+idx, 2);
return true;
}
bool of_ASSIGN(vthread_t thr, vvp_code_t cp)
{
unsigned char bit_val = thr_get_bit(thr, cp->bit_idx[1]);
schedule_assign(cp->iptr, bit_val, cp->bit_idx[0]);
return true;
}
bool of_ASSIGN_X0(vthread_t thr, vvp_code_t cp)
{
unsigned char bit_val = thr_get_bit(thr, cp->bit_idx[1]);
vvp_ipoint_t itmp = ipoint_index(cp->iptr, thr->index[0]);
schedule_assign(itmp, bit_val, cp->bit_idx[0]);
return true;
}
bool of_ASSIGN_MEM(vthread_t thr, vvp_code_t cp)
{
unsigned char bit_val = thr_get_bit(thr, cp->bit_idx[1]);
schedule_memory(cp->mem, thr->index[3], bit_val, cp->bit_idx[0]);
return true;
}
bool of_BREAKPOINT(vthread_t thr, vvp_code_t cp)
{
#if defined(WITH_DEBUG)
breakpoint();
#endif
return true;
}
bool of_CMPS(vthread_t thr, vvp_code_t cp)
{
unsigned eq = 1;
unsigned eeq = 1;
unsigned lt = 0;
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
unsigned sig1 = thr_get_bit(thr, idx1 + cp->number - 1);
unsigned sig2 = thr_get_bit(thr, idx2 + cp->number - 1);
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lv = thr_get_bit(thr, idx1);
unsigned rv = thr_get_bit(thr, idx2);
if (lv > rv) {
lt = 0;
eeq = 0;
} else if (lv < rv) {
lt = 1;
eeq = 0;
}
if (eq != 2) {
if ((lv == 0) && (rv != 0))
eq = 0;
if ((lv == 1) && (rv != 1))
eq = 0;
if ((lv | rv) >= 2)
eq = 2;
}
if (idx1 >= 4) idx1 += 1;
if (idx2 >= 4) idx2 += 1;
}
if (eq == 2)
lt = 2;
else if ((sig1 == 1) && (sig2 == 0))
lt = 1;
else if ((sig1 == 0) && (sig2 == 1))
lt = 0;
thr_put_bit(thr, 4, eq);
thr_put_bit(thr, 5, lt);
thr_put_bit(thr, 6, eeq);
return true;
}
bool of_CMPU(vthread_t thr, vvp_code_t cp)
{
unsigned eq = 1;
unsigned eeq = 1;
unsigned lt = 0;
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lv = thr_get_bit(thr, idx1);
unsigned rv = thr_get_bit(thr, idx2);
if (lv > rv) {
lt = 0;
eeq = 0;
} else if (lv < rv) {
lt = 1;
eeq = 0;
}
if (eq != 2) {
if ((lv == 0) && (rv != 0))
eq = 0;
if ((lv == 1) && (rv != 1))
eq = 0;
if ((lv | rv) >= 2)
eq = 2;
}
if (idx1 >= 4) idx1 += 1;
if (idx2 >= 4) idx2 += 1;
}
if (eq == 2)
lt = 2;
thr_put_bit(thr, 4, eq);
thr_put_bit(thr, 5, lt);
thr_put_bit(thr, 6, eeq);
return true;
}
bool of_CMPX(vthread_t thr, vvp_code_t cp)
{
unsigned eq = 1;
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lv = thr_get_bit(thr, idx1);
unsigned rv = thr_get_bit(thr, idx2);
if ((lv < 2) && (rv < 2) && (lv != rv)) {
eq = 0;
break;
}
if (idx1 >= 4) idx1 += 1;
if (idx2 >= 4) idx2 += 1;
}
thr_put_bit(thr, 4, eq);
return true;
}
bool of_CMPZ(vthread_t thr, vvp_code_t cp)
{
unsigned eq = 1;
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lv = thr_get_bit(thr, idx1);
unsigned rv = thr_get_bit(thr, idx2);
if ((lv < 3) && (rv < 3) && (lv != rv)) {
eq = 0;
break;
}
if (idx1 >= 4) idx1 += 1;
if (idx2 >= 4) idx2 += 1;
}
thr_put_bit(thr, 4, eq);
return true;
}
bool of_DELAY(vthread_t thr, vvp_code_t cp)
{
//printf("thread %p: %%delay %lu\n", thr, cp->number);
schedule_vthread(thr, cp->number);
return false;
}
bool of_DELAYX(vthread_t thr, vvp_code_t cp)
{
unsigned long delay;
assert(cp->number < 4);
delay = thr->index[cp->number];
schedule_vthread(thr, delay);
return false;
}
/*
* Implement the %disable instruction by scanning the target scope for
* all the target threads. Kill the target threads and wake up a
* parent that is attempting a %join.
*
* XXXX BUG BUG!
* The scheduler probably still has a pointer to me, and this reaping
* will destroy this object. The result: dangling pointer.
*/
bool of_DISABLE(vthread_t thr, vvp_code_t cp)
{
struct __vpiScope*scope = (struct __vpiScope*)cp->handle;
if (scope->threads == 0)
return true;
struct vthread_s*head = scope->threads;
while (head->scope_next != head) {
vthread_t tmp = head->scope_next;
/* Pull the target thread out of the scope. */
tmp->scope_next->scope_prev = tmp->scope_prev;
tmp->scope_prev->scope_next = tmp->scope_next;
/* XXXX I don't support disabling threads with children. */
assert(tmp->child == 0);
assert(tmp != thr);
/* XXXX Not supported yet. */
assert(tmp->waiting_for_event == 0);
tmp->pc = 0;
tmp->i_have_ended = 1;
if (tmp->schedule_parent_on_end) {
/* If a parent is waiting in a %join, wake it up. */
assert(tmp->parent);
schedule_vthread(tmp->parent, 0);
vthread_reap(tmp);
} else if (tmp->parent) {
/* If the parent is yet to %join me, let its %join
do the reaping. */
//assert(tmp->is_scheduled == 0);
} else {
/* No parent at all. Goodby. */
vthread_reap(tmp);
}
}
return true;
}
bool of_DIV(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
if(cp->number <= 8*sizeof(unsigned long)) {
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
unsigned long lv = 0, rv = 0;
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lb = thr_get_bit(thr, idx1);
unsigned rb = thr_get_bit(thr, idx2);
if ((lb | rb) & 2)
goto x_out;
lv |= lb << idx;
rv |= rb << idx;
idx1 += 1;
if (idx2 >= 4)
idx2 += 1;
}
if (rv == 0)
goto x_out;
lv /= rv;
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
thr_put_bit(thr, cp->bit_idx[0]+idx, (lv&1) ? 1 : 0);
lv >>= 1;
}
return true;
} else {
int len=cp->number;
unsigned char *a, *b, *z, *t;
a = new unsigned char[len+1];
b = new unsigned char[len+1];
z = new unsigned char[len+1];
t = new unsigned char[len+1];
unsigned char carry;
unsigned char temp;
int mxa = -1, mxz = -1;
int i;
int current, copylen;
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lb = thr_get_bit(thr, idx1);
unsigned rb = thr_get_bit(thr, idx2);
if ((lb | rb) & 2) {
delete []t;
delete []z;
delete []b;
delete []a;
goto x_out;
}
z[idx]=lb;
a[idx]=1-rb; // for 2s complement add..
idx1 += 1;
if (idx2 >= 4)
idx2 += 1;
}
z[len]=0;
a[len]=1;
for(i=0;i<len+1;i++) {
b[i]=0;
}
for(i=len-1;i>=0;i--) {
if(!a[i]) {
mxa=i;
break;
}
}
for(i=len-1;i>=0;i--) {
if(z[i]) {
mxz=i;
break;
}
}
if((mxa>mxz)||(mxa==-1)) {
if(mxa==-1) {
fprintf(stderr, "Division By Zero error, exiting.\n");
exit(255);
}
goto tally;
}
copylen = mxa + 2;
current = mxz - mxa;
while(current > -1) {
carry = 1;
for(i=0;i<copylen;i++) {
temp = z[i+current] + a[i] + carry;
t[i] = (temp&1);
carry = (temp>>1);
}
if(carry) {
for(i=0;i<copylen;i++) {
z[i+current] = t[i];
}
b[current] = 1;
}
current--;
}
tally:
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
// n.b., z[] has the remainder...
thr_put_bit(thr, cp->bit_idx[0]+idx, b[idx]);
}
delete []t;
delete []z;
delete []b;
delete []a;
return true;
}
x_out:
for (unsigned idx = 0 ; idx < cp->number ; idx += 1)
thr_put_bit(thr, cp->bit_idx[0]+idx, 2);
return true;
}
/*
* This terminates the current thread. If there is a parent who is
* waiting for me to die, then I schedule it. At any rate, I mark
* myself as a zombie by setting my pc to 0.
*
* It is possible for this thread to have children at this %end. This
* means that my child is really my sibling created by my parent, and
* my parent will do the proper %joins in due course. For example:
*
* %fork child_1, test;
* %fork child_2, test;
* ... parent code ...
* %join;
* %join;
* %end;
*
* child_1 ;
* %end;
* child_2 ;
* %end;
*
* In this example, the main thread creates threads child_1 and
* child_2. It is possible that this thread is child_2, so there is a
* parent pointer and a child pointer, even though I did no
* %forks or %joins. This means that I have a ->child pointer and a
* ->parent pointer.
*
* If the main thread has executed the first %join, then it is waiting
* for me, and I will be reaped right away.
*
* If the main thread has not executed a %join yet, then this thread
* becomes a zombie. The main thread executes its %join eventually,
* reaping me at that time.
*
* It does not matter the order that child_1 and child_2 threads call
* %end -- child_2 will be reaped by the first %join, and child_1 will
* be reaped by the second %join.
*/
bool of_END(vthread_t thr, vvp_code_t)
{
assert(! thr->waiting_for_event);
thr->i_have_ended = 1;
thr->pc = 0;
/* If I have a parent who is waiting for me, then mark that I
have ended, and schedule that parent. Also, finish the
%join for the parent. */
if (thr->schedule_parent_on_end) {
assert(thr->parent);
schedule_vthread(thr->parent, 0);
vthread_reap(thr);
return false;
}
/* If I have no parents, then no one can %join me and there is
no reason to stick around. This can happen, for example if
I am an ``initial'' thread.
If I have children at this point, then I must have been the
main thread (there is no other parent) and an error (not
enough %joins) has been detected. */
if (thr->parent == 0) {
assert(thr->child == 0);
vthread_reap(thr);
return false;
}
/* If I make it this far, then I have a parent who may wish
to %join me. Remain a zombie so that it can. */
return false;
}
/*
* The %fork instruction causes a new child to be created and pushed
* in front of any existing child. This causes the new child to be the
* parent of any previous children, and for me to be the parent of the
* new child.
*/
bool of_FORK(vthread_t thr, vvp_code_t cp)
{
vthread_t child = vthread_new(cp->cptr2, cp->scope);
child->child = thr->child;
child->parent = thr;
thr->child = child;
if (child->child) {
assert(child->child->parent == thr);
child->child->parent = child;
}
schedule_vthread(child, 0);
return true;
}
bool of_INV(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
for (unsigned idx = 0 ; idx < cp->bit_idx[1] ; idx += 1) {
unsigned val = thr_get_bit(thr, cp->bit_idx[0]+idx);
switch (val) {
case 0:
val = 1;
break;
case 1:
val = 0;
break;
default:
val = 2;
break;
}
thr_put_bit(thr, cp->bit_idx[0]+idx, val);
}
return true;
}
/*
** Index registers, unsigned arithmetic.
*/
bool of_IX_ADD(vthread_t thr, vvp_code_t cp)
{
thr->index[cp->bit_idx[0] & 3] += cp->number;
return true;
}
bool of_IX_SUB(vthread_t thr, vvp_code_t cp)
{
thr->index[cp->bit_idx[0] & 3] -= cp->number;
return true;
}
bool of_IX_MUL(vthread_t thr, vvp_code_t cp)
{
thr->index[cp->bit_idx[0] & 3] *= cp->number;
return true;
}
bool of_IX_LOAD(vthread_t thr, vvp_code_t cp)
{
thr->index[cp->bit_idx[0] & 3] = cp->number;
return true;
}
bool of_IX_GET(vthread_t thr, vvp_code_t cp)
{
unsigned long v = 0;
for (unsigned i = 0; i<cp->number; i++) {
unsigned char vv = thr_get_bit(thr, cp->bit_idx[1] + i);
if (vv&2) {
v = ~0UL;
break;
}
v |= vv << i;
}
thr->index[cp->bit_idx[0] & 3] = v;
return true;
}
/*
* The various JMP instruction work simply by pulling the new program
* counter from the instruction and resuming. If the jump is
* conditional, then test the bit for the expected value first.
*/
bool of_JMP(vthread_t thr, vvp_code_t cp)
{
thr->pc = cp->cptr;
return true;
}
bool of_JMP0(vthread_t thr, vvp_code_t cp)
{
if (thr_get_bit(thr, cp->bit_idx[0]) == 0)
thr->pc = cp->cptr;
return true;
}
bool of_JMP0XZ(vthread_t thr, vvp_code_t cp)
{
if (thr_get_bit(thr, cp->bit_idx[0]) != 1)
thr->pc = cp->cptr;
return true;
}
bool of_JMP1(vthread_t thr, vvp_code_t cp)
{
if (thr_get_bit(thr, cp->bit_idx[0]) == 1)
thr->pc = cp->cptr;
return true;
}
/*
* The %join instruction causes the thread to wait for the one and
* only child to die. If it is already dead (and a zombie) then I
* reap it and go on. Otherwise, I tell the child that I am ready for
* it to die, and it will reschedule me when it does.
*/
bool of_JOIN(vthread_t thr, vvp_code_t cp)
{
assert(thr->child);
assert(thr->child->parent == thr);
/* If the child has already ended, reap it now. */
if (thr->child->i_have_ended) {
vthread_reap(thr->child);
return true;
}
/* Otherwise, I get to start waiting. */
thr->child->schedule_parent_on_end = 1;
return false;
}
bool of_LOAD(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
thr_put_bit(thr, cp->bit_idx[0], functor_get(cp->iptr));
return true;
}
bool of_LOAD_MEM(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned char val = memory_get(cp->mem, thr->index[3]);
thr_put_bit(thr, cp->bit_idx[0], val);
return true;
}
bool of_LOAD_X(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
assert(cp->bit_idx[1] < 4);
vvp_ipoint_t ptr = ipoint_index(cp->iptr, thr->index[cp->bit_idx[1]]);
thr_put_bit(thr, cp->bit_idx[0], functor_get(ptr));
return true;
}
bool of_MOD(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
if(cp->number <= 8*sizeof(unsigned long)) {
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
unsigned long lv = 0, rv = 0;
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lb = thr_get_bit(thr, idx1);
unsigned rb = thr_get_bit(thr, idx2);
if ((lb | rb) & 2)
goto x_out;
lv |= lb << idx;
rv |= rb << idx;
idx1 += 1;
if (idx2 >= 4)
idx2 += 1;
}
if (rv == 0)
goto x_out;
lv %= rv;
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
thr_put_bit(thr, cp->bit_idx[0]+idx, (lv&1) ? 1 : 0);
lv >>= 1;
}
return true;
} else {
int len=cp->number;
unsigned char *a, *z, *t;
a = new unsigned char[len+1];
z = new unsigned char[len+1];
t = new unsigned char[len+1];
unsigned char carry;
unsigned char temp;
int mxa = -1, mxz = -1;
int i;
int current, copylen;
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lb = thr_get_bit(thr, idx1);
unsigned rb = thr_get_bit(thr, idx2);
if ((lb | rb) & 2) {
delete []t;
delete []z;
delete []a;
goto x_out;
}
z[idx]=lb;
a[idx]=1-rb; // for 2s complement add..
idx1 += 1;
if (idx2 >= 4)
idx2 += 1;
}
z[len]=0;
a[len]=1;
for(i=len-1;i>=0;i--)
{
if(!a[i])
{
mxa=i; break;
}
}
for(i=len-1;i>=0;i--)
{
if(z[i])
{
mxz=i; break;
}
}
if((mxa>mxz)||(mxa==-1))
{
if(mxa==-1)
{
fprintf(stderr, "Division By Zero error, exiting.\n");
exit(255);
}
goto tally;
}
copylen = mxa + 2;
current = mxz - mxa;
while(current > -1)
{
carry = 1;
for(i=0;i<copylen;i++)
{
temp = z[i+current] + a[i] + carry;
t[i] = (temp&1);
carry = (temp>>1);
}
if(carry)
{
for(i=0;i<copylen;i++)
{
z[i+current] = t[i];
}
}
current--;
}
tally:
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
thr_put_bit(thr, cp->bit_idx[0]+idx, z[idx]);
}
delete []t;
delete []z;
delete []a;
return true;
}
x_out:
for (unsigned idx = 0 ; idx < cp->number ; idx += 1)
thr_put_bit(thr, cp->bit_idx[0]+idx, 2);
return true;
}
bool of_MOV(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
if (cp->bit_idx[1] >= 4) {
for (unsigned idx = 0 ; idx < cp->number ; idx += 1)
thr_put_bit(thr,
cp->bit_idx[0]+idx,
thr_get_bit(thr, cp->bit_idx[1]+idx));
} else {
for (unsigned idx = 0 ; idx < cp->number ; idx += 1)
thr_put_bit(thr, cp->bit_idx[0]+idx, cp->bit_idx[1]);
}
return true;
}
bool of_MUL(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
if(cp->number <= 8*sizeof(unsigned long)) {
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
unsigned long lv = 0, rv = 0;
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lb = thr_get_bit(thr, idx1);
unsigned rb = thr_get_bit(thr, idx2);
if ((lb | rb) & 2)
goto x_out;
lv |= lb << idx;
rv |= rb << idx;
idx1 += 1;
if (idx2 >= 4)
idx2 += 1;
}
lv *= rv;
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
thr_put_bit(thr, cp->bit_idx[0]+idx, (lv&1) ? 1 : 0);
lv >>= 1;
}
return true;
} else {
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
unsigned char *a, *b, *sum;
a = new unsigned char[cp->number];
b = new unsigned char[cp->number];
sum = new unsigned char[cp->number];
int mxa = -1;
int mxb = -1;
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lb = thr_get_bit(thr, idx1);
unsigned rb = thr_get_bit(thr, idx2);
if ((lb | rb) & 2)
{
delete[]sum;
delete[]b;
delete[]a;
goto x_out;
}
if((a[idx] = lb)) mxa=idx+1;
if((b[idx] = rb)) mxb=idx;
sum[idx]=0;
idx1 += 1;
if (idx2 >= 4)
idx2 += 1;
}
// do "unsigned ZZ sum = a * b" the hard way..
for(int i=0;i<=mxb;i++)
{
if(b[i])
{
unsigned char carry=0;
unsigned char temp;
for(int j=0;j<=mxa;j++)
{
if(i+j>=(int)cp->number) break;
temp=sum[i+j]+a[j]+carry;
sum[i+j]=(temp&1);
carry=(temp>>1);
}
}
}
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
thr_put_bit(thr, cp->bit_idx[0]+idx, sum[idx]);
}
delete[]sum;
delete[]b;
delete[]a;
return true;
}
x_out:
for (unsigned idx = 0 ; idx < cp->number ; idx += 1)
thr_put_bit(thr, cp->bit_idx[0]+idx, 2);
return true;
}
bool of_NOOP(vthread_t thr, vvp_code_t cp)
{
return true;
}
bool of_NORR(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned lb = 1;
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned rb = thr_get_bit(thr, idx2+idx);
if (rb == 1) {
lb = 0;
break;
}
if (rb != 0)
lb = 2;
}
thr_put_bit(thr, cp->bit_idx[0], lb);
return true;
}
bool of_ANDR(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned lb = 1;
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned rb = thr_get_bit(thr, idx2+idx);
if (rb == 0) {
lb = 0;
break;
}
if (rb != 1)
lb = 2;
}
thr_put_bit(thr, cp->bit_idx[0], lb);
return true;
}
bool of_NANDR(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned lb = 0;
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned rb = thr_get_bit(thr, idx2+idx);
if (rb == 0) {
lb = 1;
break;
}
if (rb != 1)
lb = 2;
}
thr_put_bit(thr, cp->bit_idx[0], lb);
return true;
}
bool of_ORR(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned lb = 0;
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned rb = thr_get_bit(thr, idx2+idx);
if (rb == 1) {
lb = 1;
break;
}
if (rb != 0)
lb = 2;
}
thr_put_bit(thr, cp->bit_idx[0], lb);
return true;
}
bool of_XORR(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned lb = 0;
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned rb = thr_get_bit(thr, idx2+idx);
if (rb == 1)
lb ^= 1;
else if (rb != 0) {
lb = 2;
break;
}
}
thr_put_bit(thr, cp->bit_idx[0], lb);
return true;
}
bool of_XNORR(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned lb = 1;
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned rb = thr_get_bit(thr, idx2+idx);
if (rb == 1)
lb ^= 1;
else if (rb != 0) {
lb = 2;
break;
}
}
thr_put_bit(thr, cp->bit_idx[0], lb);
return true;
}
bool of_OR(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lb = thr_get_bit(thr, idx1);
unsigned rb = thr_get_bit(thr, idx2);
if ((lb == 1) || (rb == 1)) {
thr_put_bit(thr, idx1, 1);
} else if ((lb == 0) && (rb == 0)) {
thr_put_bit(thr, idx1, 0);
} else {
thr_put_bit(thr, idx1, 2);
}
idx1 += 1;
if (idx2 >= 4)
idx2 += 1;
}
return true;
}
static const unsigned char strong_values[4] = {St0, St1, StX, HiZ};
bool of_SET(vthread_t thr, vvp_code_t cp)
{
unsigned char bit_val = thr_get_bit(thr, cp->bit_idx[0]);
functor_set(cp->iptr, bit_val, strong_values[bit_val], true);
return true;
}
bool of_SET_MEM(vthread_t thr, vvp_code_t cp)
{
unsigned char val = thr_get_bit(thr, cp->bit_idx[0]);
memory_set(cp->mem, thr->index[3], val);
return true;
}
bool of_SET_X(vthread_t thr, vvp_code_t cp)
{
unsigned char bit_val = thr_get_bit(thr, cp->bit_idx[0]);
vvp_ipoint_t itmp = ipoint_index(cp->iptr, thr->index[cp->bit_idx[1]&3]);
functor_set(itmp, bit_val, strong_values[bit_val], true);
return true;
}
bool of_SHIFTL_I0(vthread_t thr, vvp_code_t cp)
{
unsigned base = cp->bit_idx[0];
unsigned wid = cp->number;
unsigned long shift = thr->index[0];
if (shift >= wid) {
for (unsigned idx = 0 ; idx < wid ; idx += 1)
thr_put_bit(thr, base+idx, 0);
} else if (shift > 0) {
for (unsigned idx = wid ; idx > shift ; idx -= 1) {
unsigned src = base+idx-shift-1;
unsigned dst = base + idx - 1;
thr_put_bit(thr, dst, thr_get_bit(thr, src));
}
for (unsigned idx = 0 ; idx < shift ; idx += 1)
thr_put_bit(thr, base+idx, 0);
}
return true;
}
/*
* This is an unsigned right shift.
*/
bool of_SHIFTR_I0(vthread_t thr, vvp_code_t cp)
{
unsigned base = cp->bit_idx[0];
unsigned wid = cp->number;
unsigned long shift = thr->index[0];
if (shift >= wid) {
for (unsigned idx = 0 ; idx < wid ; idx += 1)
thr_put_bit(thr, base+idx, 0);
} else if (shift > 0) {
for (unsigned idx = 0 ; idx < (wid-shift) ; idx += 1) {
unsigned src = base + idx + shift;
unsigned dst = base + idx;
thr_put_bit(thr, dst, thr_get_bit(thr, src));
}
for (unsigned idx = (wid-shift) ; idx < wid ; idx += 1)
thr_put_bit(thr, base+idx, 0);
}
return true;
}
bool of_SUB(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned long*lva = vector_to_array(thr, cp->bit_idx[0], cp->number);
unsigned long*lvb = vector_to_array(thr, cp->bit_idx[1], cp->number);
if (lva == 0 || lvb == 0)
goto x_out;
unsigned carry;
carry = 1;
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned long tmp;
unsigned sum = carry;
tmp = lva[idx/CPU_BITS];
sum += 1 & (tmp >> (idx%CPU_BITS));
tmp = lvb[idx/CPU_BITS];
sum += 1 & ~(tmp >> (idx%CPU_BITS));
carry = sum / 2;
thr_put_bit(thr, cp->bit_idx[0]+idx, (sum&1) ? 1 : 0);
}
delete[]lva;
delete[]lvb;
return true;
x_out:
delete[]lva;
delete[]lvb;
for (unsigned idx = 0 ; idx < cp->number ; idx += 1)
thr_put_bit(thr, cp->bit_idx[0]+idx, 2);
return true;
}
bool of_VPI_CALL(vthread_t thr, vvp_code_t cp)
{
// printf("thread %p: %%vpi_call\n", thr);
vpip_execute_vpi_call(thr, cp->handle);
return schedule_finished()? false : true;
}
/*
* Implement the wait by locating the functor for the event, and
* adding this thread to the threads list for the event.
*/
bool of_WAIT(vthread_t thr, vvp_code_t cp)
{
assert(! thr->waiting_for_event);
thr->waiting_for_event = 1;
vvp_event_t ep = dynamic_cast<vvp_event_t>(functor_index(cp->iptr));
assert(ep);
thr->wait_next = ep->threads;
ep->threads = thr;
return false;
}
bool of_XNOR(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lb = thr_get_bit(thr, idx1);
unsigned rb = thr_get_bit(thr, idx2);
if ((lb == 1) && (rb == 1)) {
thr_put_bit(thr, idx1, 1);
} else if ((lb == 0) && (rb == 0)) {
thr_put_bit(thr, idx1, 1);
} else if ((lb == 1) && (rb == 0)) {
thr_put_bit(thr, idx1, 0);
} else if ((lb == 0) && (rb == 1)) {
thr_put_bit(thr, idx1, 0);
} else {
thr_put_bit(thr, idx1, 2);
}
idx1 += 1;
if (idx2 >= 4)
idx2 += 1;
}
return true;
}
bool of_XOR(vthread_t thr, vvp_code_t cp)
{
assert(cp->bit_idx[0] >= 4);
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lb = thr_get_bit(thr, idx1);
unsigned rb = thr_get_bit(thr, idx2);
if ((lb == 1) && (rb == 1)) {
thr_put_bit(thr, idx1, 0);
} else if ((lb == 0) && (rb == 0)) {
thr_put_bit(thr, idx1, 0);
} else if ((lb == 1) && (rb == 0)) {
thr_put_bit(thr, idx1, 1);
} else if ((lb == 0) && (rb == 1)) {
thr_put_bit(thr, idx1, 1);
} else {
thr_put_bit(thr, idx1, 2);
}
idx1 += 1;
if (idx2 >= 4)
idx2 += 1;
}
return true;
}
bool of_ZOMBIE(vthread_t thr, vvp_code_t)
{
thr->pc = 0;
if ((thr->parent == 0) && (thr->child == 0))
delete thr;
return false;
}
/*
* $Log: vthread.cc,v $
* Revision 1.64 2001/11/06 03:07:22 steve
* Code rearrange. (Stephan Boettcher)
*
* Revision 1.63 2001/11/01 03:00:20 steve
* Add force/cassign/release/deassign support. (Stephan Boettcher)
*
* Revision 1.62 2001/10/31 04:27:47 steve
* Rewrite the functor type to have fewer functor modes,
* and use objects to manage the different types.
* (Stephan Boettcher)
*
* Revision 1.61 2001/10/25 04:19:53 steve
* VPI support for callback to return values.
*
* Revision 1.60 2001/10/23 03:49:13 steve
* Fix carry between works for %add instruction.
*
* Revision 1.59 2001/10/20 23:20:32 steve
* Catch and X division by 0.
*
* Revision 1.58 2001/10/16 01:26:55 steve
* Add %div support (Anthony Bybell)
*
* Revision 1.57 2001/10/14 17:36:19 steve
* Forgot to propagate carry.
*
* Revision 1.56 2001/10/14 16:36:43 steve
* Very wide multiplication (Anthony Bybell)
*
* Revision 1.55 2001/09/15 18:27:05 steve
* Make configure detect malloc.h
*
* Revision 1.54 2001/09/07 23:29:28 steve
* Redo of_SUBU in a more obvious algorithm, that
* is not significantly slower. Also, clean up the
* implementation of %mov from a constant.
*
* Fix initial clearing of vector by vector_to_array
*
* Revision 1.53 2001/08/26 22:59:32 steve
* Add the assign/x0 and set/x opcodes.
*
* Revision 1.52 2001/08/08 00:53:50 steve
* signed/unsigned warnings?
*
* Revision 1.51 2001/07/22 00:04:50 steve
* Add the load/x instruction for bit selects.
*
* Revision 1.50 2001/07/20 04:57:00 steve
* Fix of_END when a middle thread ends.
*
* Revision 1.49 2001/07/19 04:40:55 steve
* Add support for the delayx opcode.
*
* Revision 1.48 2001/07/04 04:57:10 steve
* Relax limit on behavioral subtraction.
*
* Revision 1.47 2001/06/30 21:07:26 steve
* Support non-const right shift (unsigned).
*
* Revision 1.46 2001/06/23 18:26:26 steve
* Add the %shiftl/i0 instruction.
*
* Revision 1.45 2001/06/22 00:03:05 steve
* Infinitely wide behavioral add.
*
* Revision 1.44 2001/06/18 01:09:32 steve
* More behavioral unary reduction operators.
* (Stephan Boettcher)
*
* Revision 1.43 2001/06/16 23:45:05 steve
* Add support for structural multiply in t-dll.
* Add code generators and vvp support for both
* structural and behavioral multiply.
*
* Revision 1.42 2001/05/30 03:02:35 steve
* Propagate strength-values instead of drive strengths.
*
* Revision 1.41 2001/05/24 04:20:10 steve
* Add behavioral modulus.
*
* Revision 1.40 2001/05/20 00:56:48 steve
* Make vthread_put_but expand the space if needed.
*
* Revision 1.39 2001/05/10 00:26:53 steve
* VVP support for memories in expressions,
* including general support for thread bit
* vectors as system task parameters.
* (Stephan Boettcher)
*
* Revision 1.38 2001/05/08 23:59:33 steve
* Add ivl and vvp.tgt support for memories in
* expressions and l-values. (Stephan Boettcher)
*
* Revision 1.37 2001/05/08 23:32:26 steve
* Add to the debugger the ability to view and
* break on functors.
*
* Add strengths to functors at compile time,
* and Make functors pass their strengths as they
* propagate their output.
*
* Revision 1.36 2001/05/06 17:42:22 steve
* Add the %ix/get instruction. (Stephan Boettcher)
*
* Revision 1.35 2001/05/05 23:55:46 steve
* Add the beginnings of an interactive debugger.
*
* Revision 1.34 2001/05/02 23:16:50 steve
* Document memory related opcodes,
* parser uses numbv_s structures instead of the
* symbv_s and a mess of unions,
* Add the %is/sub instruction.
* (Stephan Boettcher)
*
* Revision 1.33 2001/05/02 01:57:26 steve
* Support behavioral subtraction.
*
* Revision 1.32 2001/05/02 01:37:38 steve
* initialize is_schedule.
*
* Revision 1.31 2001/05/01 05:00:02 steve
* Implement %ix/load.
*
* Revision 1.30 2001/05/01 01:09:39 steve
* Add support for memory objects. (Stephan Boettcher)
*
* Revision 1.29 2001/04/21 00:34:39 steve
* Working %disable and reap handling references from scheduler.
*
* Revision 1.28 2001/04/18 05:04:19 steve
* %end complete the %join for the parent.
*
* Revision 1.27 2001/04/18 04:21:23 steve
* Put threads into scopes.
*
* Revision 1.26 2001/04/15 16:37:48 steve
* add XOR support.
*
* Revision 1.25 2001/04/15 04:07:56 steve
* Add support for behavioral xnor.
*
* Revision 1.24 2001/04/14 05:10:05 steve
* Initialize the waiting_for_event member.
*
* Revision 1.23 2001/04/13 03:55:18 steve
* More complete reap of all threads.
*
* Revision 1.22 2001/04/05 01:12:28 steve
* Get signed compares working correctly in vvp.
*
* Revision 1.21 2001/04/03 03:18:34 steve
* support functor_set push for blocking assignment.
*
* Revision 1.20 2001/04/01 22:25:33 steve
* Add the reduction nor instruction.
*
* Revision 1.19 2001/04/01 07:22:08 steve
* Implement the less-then and %or instructions.
*/