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Optimize ==1 when in context where x vs z doesnt matter.

This commit is contained in:
steve 2002-09-13 03:12:50 +00:00
parent dac99b9374
commit 28725d0d74
3 changed files with 98 additions and 67 deletions
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124
tgt-vvp/eval_expr.c
View File

@ -17,7 +17,7 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CVS_IDENT
#ident "$Id: eval_expr.c,v 1.75 2002/09/12 15:49:43 steve Exp $"
#ident "$Id: eval_expr.c,v 1.76 2002/09/13 03:12:50 steve Exp $"
#endif
# include "vvp_priv.h"
@ -28,7 +28,6 @@
# include <stdlib.h>
# include <assert.h>
struct vector_info draw_eval_expr_wid(ivl_expr_t exp, unsigned wid);
static unsigned char allocation_map[0x10000/8];
@ -162,16 +161,22 @@ unsigned long get_number_immediate(ivl_expr_t ex)
return imm;
}
/*
* The xz_ok_flag is true if the output is going to be further
* processed so that x and z values are equivilent. This may allow for
* new optimizations.
*/
static struct vector_info draw_eq_immediate(ivl_expr_t exp, unsigned ewid,
ivl_expr_t le,
ivl_expr_t re)
ivl_expr_t re,
int xz_ok_flag)
{
unsigned wid;
struct vector_info lv;
unsigned long imm = get_number_immediate(re);
wid = ivl_expr_width(le);
lv = draw_eval_expr_wid(le, wid);
lv = draw_eval_expr_wid(le, wid, xz_ok_flag);
switch (ivl_expr_opcode(exp)) {
case 'E': /* === */
@ -183,6 +188,12 @@ static struct vector_info draw_eq_immediate(ivl_expr_t exp, unsigned ewid,
break;
case 'e': /* == */
/* If this is a single bit being compared to 1, and the
output doesn't care about x vs z, then just return
the value itself. */
if (xz_ok_flag && (lv.wid == 1) && (imm == 1))
break;
fprintf(vvp_out, " %%cmpi/u %u, %lu, %u;\n",
lv.base, imm, wid);
clr_vector(lv);
@ -215,18 +226,21 @@ static struct vector_info draw_eq_immediate(ivl_expr_t exp, unsigned ewid,
/* Move the result out out the 4-7 bit that the compare
uses. This is because that bit may be clobbered by other
expressions. */
{ unsigned short base = allocate_vector(ewid);
fprintf(vvp_out, " %%mov %u, %u, 1;\n", base, lv.base);
lv.base = base;
lv.wid = ewid;
if (ewid > 1)
fprintf(vvp_out, " %%mov %u, 0, %u;\n", base+1, ewid-1);
if (lv.base < 8) {
unsigned short base = allocate_vector(ewid);
fprintf(vvp_out, " %%mov %u, %u, 1;\n", base, lv.base);
lv.base = base;
lv.wid = ewid;
if (ewid > 1)
fprintf(vvp_out, " %%mov %u, 0, %u;\n", base+1, ewid-1);
}
return lv;
}
static struct vector_info draw_binary_expr_eq(ivl_expr_t exp, unsigned ewid)
static struct vector_info draw_binary_expr_eq(ivl_expr_t exp,
unsigned ewid,
int xz_ok_flag)
{
ivl_expr_t le = ivl_expr_oper1(exp);
ivl_expr_t re = ivl_expr_oper2(exp);
@ -238,19 +252,19 @@ static struct vector_info draw_binary_expr_eq(ivl_expr_t exp, unsigned ewid)
if ((ivl_expr_type(re) == IVL_EX_ULONG)
&& (0 == (ivl_expr_uvalue(re) & ~0xffff)))
return draw_eq_immediate(exp, ewid, le, re);
return draw_eq_immediate(exp, ewid, le, re, xz_ok_flag);
if ((ivl_expr_type(re) == IVL_EX_NUMBER)
&& (! number_is_unknown(re))
&& number_is_immediate(re, 16))
return draw_eq_immediate(exp, ewid, le, re);
return draw_eq_immediate(exp, ewid, le, re, xz_ok_flag);
wid = ivl_expr_width(le);
if (ivl_expr_width(re) > wid)
wid = ivl_expr_width(re);
lv = draw_eval_expr_wid(le, wid);
rv = draw_eval_expr_wid(re, wid);
lv = draw_eval_expr_wid(le, wid, xz_ok_flag);
rv = draw_eval_expr_wid(re, wid, xz_ok_flag);
switch (ivl_expr_opcode(exp)) {
case 'E': /* === */
@ -339,7 +353,7 @@ static struct vector_info draw_binary_expr_land(ivl_expr_t exp, unsigned wid)
struct vector_info rv;
lv = draw_eval_expr(le);
lv = draw_eval_expr(le, 1);
if ((lv.base >= 4) && (lv.wid > 1)) {
struct vector_info tmp;
@ -351,7 +365,7 @@ static struct vector_info draw_binary_expr_land(ivl_expr_t exp, unsigned wid)
lv = tmp;
}
rv = draw_eval_expr(re);
rv = draw_eval_expr(re, 1);
if ((rv.base >= 4) && (rv.wid > 1)) {
struct vector_info tmp;
clr_vector(rv);
@ -411,7 +425,7 @@ static struct vector_info draw_binary_expr_lor(ivl_expr_t exp, unsigned wid)
struct vector_info lv;
struct vector_info rv;
lv = draw_eval_expr_wid(le, wid);
lv = draw_eval_expr_wid(le, wid, 1);
/* if the left operand has width, then evaluate the single-bit
logical equivilent. */
@ -425,7 +439,7 @@ static struct vector_info draw_binary_expr_lor(ivl_expr_t exp, unsigned wid)
lv = tmp;
}
rv = draw_eval_expr_wid(re, wid);
rv = draw_eval_expr_wid(re, wid, 1);
/* if the right operand has width, then evaluate the single-bit
logical equivilent. */
@ -495,8 +509,8 @@ static struct vector_info draw_binary_expr_le(ivl_expr_t exp, unsigned wid)
if (ivl_expr_width(re) > owid)
owid = ivl_expr_width(re);
lv = draw_eval_expr_wid(le, owid);
rv = draw_eval_expr_wid(re, owid);
lv = draw_eval_expr_wid(le, owid, 1);
rv = draw_eval_expr_wid(re, owid, 1);
switch (ivl_expr_opcode(exp)) {
case 'G':
@ -555,8 +569,8 @@ static struct vector_info draw_binary_expr_logic(ivl_expr_t exp,
struct vector_info lv;
struct vector_info rv;
lv = draw_eval_expr_wid(le, wid);
rv = draw_eval_expr_wid(re, wid);
lv = draw_eval_expr_wid(le, wid, 1);
rv = draw_eval_expr_wid(re, wid, 1);
/* The result goes into the left operand, and that is returned
as the result. The instructions do not allow the lv value
@ -659,7 +673,7 @@ static struct vector_info draw_binary_expr_lrs(ivl_expr_t exp, unsigned wid)
default: {
struct vector_info rv;
rv = draw_eval_expr(re);
rv = draw_eval_expr(re, 0);
fprintf(vvp_out, " %%ix/get 0, %u, %u;\n",
rv.base, rv.wid);
clr_vector(rv);
@ -667,7 +681,7 @@ static struct vector_info draw_binary_expr_lrs(ivl_expr_t exp, unsigned wid)
}
}
lv = draw_eval_expr_wid(le, wid);
lv = draw_eval_expr_wid(le, wid, 0);
switch (ivl_expr_opcode(exp)) {
@ -693,7 +707,7 @@ static struct vector_info draw_add_immediate(ivl_expr_t le,
struct vector_info lv;
unsigned long imm;
lv = draw_eval_expr_wid(le, wid);
lv = draw_eval_expr_wid(le, wid, 1);
assert(lv.wid == wid);
imm = get_number_immediate(re);
@ -730,7 +744,7 @@ static struct vector_info draw_sub_immediate(ivl_expr_t le,
struct vector_info lv;
unsigned long imm;
lv = draw_eval_expr_wid(le, wid);
lv = draw_eval_expr_wid(le, wid, 1);
assert(lv.wid == wid);
imm = get_number_immediate(re);
@ -748,7 +762,7 @@ static struct vector_info draw_mul_immediate(ivl_expr_t le,
struct vector_info lv;
unsigned long imm;
lv = draw_eval_expr_wid(le, wid);
lv = draw_eval_expr_wid(le, wid, 1);
assert(lv.wid == wid);
imm = get_number_immediate(re);
@ -794,8 +808,8 @@ static struct vector_info draw_binary_expr_arith(ivl_expr_t exp, unsigned wid)
&& number_is_immediate(re, 16))
return draw_mul_immediate(le, re, wid);
lv = draw_eval_expr_wid(le, wid);
rv = draw_eval_expr_wid(re, wid);
lv = draw_eval_expr_wid(le, wid, 1);
rv = draw_eval_expr_wid(re, wid, 1);
assert(lv.wid == wid);
assert(rv.wid == wid);
@ -845,7 +859,9 @@ static struct vector_info draw_binary_expr_arith(ivl_expr_t exp, unsigned wid)
return lv;
}
static struct vector_info draw_binary_expr(ivl_expr_t exp, unsigned wid)
static struct vector_info draw_binary_expr(ivl_expr_t exp,
unsigned wid,
int xz_ok_flag)
{
struct vector_info rv;
@ -858,7 +874,7 @@ static struct vector_info draw_binary_expr(ivl_expr_t exp, unsigned wid)
case 'e': /* == */
case 'N': /* !== */
case 'n': /* != */
rv = draw_binary_expr_eq(exp, wid);
rv = draw_binary_expr_eq(exp, wid, xz_ok_flag);
break;
case '<':
@ -910,7 +926,7 @@ static struct vector_info draw_bitsel_expr(ivl_expr_t exp, unsigned wid)
/* Evaluate the bit select expression and save the result into
index register 0. */
res = draw_eval_expr(sel);
res = draw_eval_expr(sel, 0);
fprintf(vvp_out, " %%ix/get 0, %u,%u;\n", res.base, res.wid);
clr_vector(res);
@ -968,7 +984,7 @@ static struct vector_info draw_concat_expr(ivl_expr_t exp, unsigned wid)
unsigned awid = ivl_expr_width(arg);
/* Evaluate this sub expression. */
struct vector_info avec = draw_eval_expr_wid(arg, awid);
struct vector_info avec = draw_eval_expr_wid(arg, awid, 0);
unsigned trans = awid;
if ((off + awid) > wid)
@ -1197,7 +1213,7 @@ void draw_memory_index_expr(ivl_memory_t mem, ivl_expr_t ae)
break;
}
default: {
struct vector_info addr = draw_eval_expr(ae);
struct vector_info addr = draw_eval_expr(ae, 0);
fprintf(vvp_out, " %%ix/get 3, %u, %u;\n",
addr.base, addr.wid);
clr_vector(addr);
@ -1247,7 +1263,7 @@ static struct vector_info draw_select_expr(ivl_expr_t exp, unsigned wid)
ivl_expr_t shift = ivl_expr_oper2(exp);
/* Evaluate the sub-expression. */
subv = draw_eval_expr(sube);
subv = draw_eval_expr(sube, 0);
/* Any bit select of a constant zero is another constant zero,
so short circuit and return the value we know. */
@ -1258,7 +1274,7 @@ static struct vector_info draw_select_expr(ivl_expr_t exp, unsigned wid)
/* Evaluate the bit select base expression and store the
result into index register 0. */
shiv = draw_eval_expr(shift);
shiv = draw_eval_expr(shift, 1);
fprintf(vvp_out, " %%ix/get 0, %u, %u;\n", shiv.base, shiv.wid);
clr_vector(shiv);
@ -1302,7 +1318,7 @@ static struct vector_info draw_ternary_expr(ivl_expr_t exp, unsigned wid)
lab_false = local_count++;
lab_out = local_count++;
tmp = draw_eval_expr(cond);
tmp = draw_eval_expr(cond, 1);
clr_vector(tmp);
if ((tmp.base >= 4) && (tmp.wid > 1)) {
@ -1322,11 +1338,11 @@ static struct vector_info draw_ternary_expr(ivl_expr_t exp, unsigned wid)
/* Ambiguous case. Evaluate both true and false expressions,
and use %blend to merge them. */
tmp = draw_eval_expr_wid(true_ex, wid);
tmp = draw_eval_expr_wid(true_ex, wid, 0);
fprintf(vvp_out, " %%mov %u, %u, %u;\n", res.base, tmp.base, wid);
clr_vector(tmp);
tmp = draw_eval_expr_wid(false_ex, wid);
tmp = draw_eval_expr_wid(false_ex, wid, 0);
fprintf(vvp_out, " %%blend %u, %u, %u;\n", res.base, tmp.base, wid);
fprintf(vvp_out, " %%jmp T_%d.%d;\n", thread_count, lab_out);
if (tmp.base >= 8)
@ -1335,7 +1351,7 @@ static struct vector_info draw_ternary_expr(ivl_expr_t exp, unsigned wid)
/* This is the true case. Just evaluate the true expression. */
fprintf(vvp_out, "T_%d.%d ;\n", thread_count, lab_true);
tmp = draw_eval_expr_wid(true_ex, wid);
tmp = draw_eval_expr_wid(true_ex, wid, 0);
fprintf(vvp_out, " %%mov %u, %u, %u;\n", res.base, tmp.base, wid);
fprintf(vvp_out, " %%jmp T_%d.%d;\n", thread_count, lab_out);
if (tmp.base >= 8)
@ -1345,7 +1361,7 @@ static struct vector_info draw_ternary_expr(ivl_expr_t exp, unsigned wid)
/* This is the false case. Just evaluate the false expression. */
fprintf(vvp_out, "T_%d.%d ;\n", thread_count, lab_false);
tmp = draw_eval_expr_wid(false_ex, wid);
tmp = draw_eval_expr_wid(false_ex, wid, 0);
fprintf(vvp_out, " %%mov %u, %u, %u;\n", res.base, tmp.base, wid);
if (tmp.base >= 8)
clr_vector(tmp);
@ -1402,7 +1418,7 @@ static struct vector_info draw_sfunc_expr(ivl_expr_t exp, unsigned wid)
vec = (struct vector_info *)
realloc(vec, (vecs+1)*sizeof(struct vector_info));
vec[vecs] = draw_eval_expr(expr);
vec[vecs] = draw_eval_expr(expr, 0);
vecs++;
}
@ -1516,7 +1532,7 @@ static struct vector_info draw_ufunc_expr(ivl_expr_t exp, unsigned wid)
unsigned pin, bit;
res = draw_eval_expr_wid(ivl_expr_parm(exp, idx),
ivl_signal_pins(port));
ivl_signal_pins(port), 0);
bit = res.base;
assert(res.wid <= ivl_signal_pins(port));
for (pin = 0 ; pin < res.wid ; pin += 1) {
@ -1583,7 +1599,7 @@ static struct vector_info draw_unary_expr(ivl_expr_t exp, unsigned wid)
switch (ivl_expr_opcode(exp)) {
case '~':
res = draw_eval_expr_wid(sub, wid);
res = draw_eval_expr_wid(sub, wid, 1);
switch (res.base) {
case 0:
res.base = 1;
@ -1606,7 +1622,7 @@ static struct vector_info draw_unary_expr(ivl_expr_t exp, unsigned wid)
complement of the number. That is the 1's complement
(bitwise invert) with a 1 added in. Note that the
%sub subtracts -1 (1111...) to get %add of +1. */
res = draw_eval_expr_wid(sub, wid);
res = draw_eval_expr_wid(sub, wid, 1);
switch (res.base) {
case 0:
res.base = 0;
@ -1626,7 +1642,7 @@ static struct vector_info draw_unary_expr(ivl_expr_t exp, unsigned wid)
break;
case '!':
res = draw_eval_expr(sub);
res = draw_eval_expr(sub, 1);
if (res.wid > 1) {
/* a ! on a vector is implemented with a reduction
nor. Generate the result into the first bit of
@ -1678,7 +1694,7 @@ static struct vector_info draw_unary_expr(ivl_expr_t exp, unsigned wid)
case '&':
case '|':
case '^':
res = draw_eval_expr(sub);
res = draw_eval_expr(sub, 0);
if (res.wid > 1) {
struct vector_info tmp;
/* If the previous result is in the constant area
@ -1728,7 +1744,8 @@ static struct vector_info draw_unary_expr(ivl_expr_t exp, unsigned wid)
return res;
}
struct vector_info draw_eval_expr_wid(ivl_expr_t exp, unsigned wid)
struct vector_info draw_eval_expr_wid(ivl_expr_t exp, unsigned wid,
int xz_ok_flag)
{
struct vector_info res;
@ -1747,7 +1764,7 @@ struct vector_info draw_eval_expr_wid(ivl_expr_t exp, unsigned wid)
break;
case IVL_EX_BINARY:
res = draw_binary_expr(exp, wid);
res = draw_binary_expr(exp, wid, xz_ok_flag);
break;
case IVL_EX_BITSEL:
@ -1794,13 +1811,16 @@ struct vector_info draw_eval_expr_wid(ivl_expr_t exp, unsigned wid)
return res;
}
struct vector_info draw_eval_expr(ivl_expr_t exp)
struct vector_info draw_eval_expr(ivl_expr_t exp, int xz_ok_flag)
{
return draw_eval_expr_wid(exp, ivl_expr_width(exp));
return draw_eval_expr_wid(exp, ivl_expr_width(exp), xz_ok_flag);
}
/*
* $Log: eval_expr.c,v $
* Revision 1.76 2002/09/13 03:12:50 steve
* Optimize ==1 when in context where x vs z doesnt matter.
*
* Revision 1.75 2002/09/12 15:49:43 steve
* Add support for binary nand operator.
*

14
tgt-vvp/vvp_priv.h
View File

@ -19,7 +19,7 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CVS_IDENT
#ident "$Id: vvp_priv.h,v 1.19 2002/08/27 05:39:57 steve Exp $"
#ident "$Id: vvp_priv.h,v 1.20 2002/09/13 03:12:50 steve Exp $"
#endif
# include "ivl_target.h"
@ -83,14 +83,19 @@ extern void draw_input_from_net(ivl_nexus_t nex);
* allocation. When the caller is done with the bits, it must release
* the vector with clr_vector so that the code generator can reuse
* those bits.
*
* The xz_ok_flag is normally false. Set it to true if the result is
* going to be further processed so that x and z values are treated
* identically.
*/
struct vector_info {
unsigned short base;
unsigned short wid;
};
extern struct vector_info draw_eval_expr(ivl_expr_t exp);
extern struct vector_info draw_eval_expr_wid(ivl_expr_t exp, unsigned w);
extern struct vector_info draw_eval_expr(ivl_expr_t exp, int xz_ok_flag);
extern struct vector_info draw_eval_expr_wid(ivl_expr_t exp, unsigned w,
int xz_ok_flag);
/*
* This function draws code to evaluate the index expression exp for
@ -115,6 +120,9 @@ extern unsigned thread_count;
/*
* $Log: vvp_priv.h,v $
* Revision 1.20 2002/09/13 03:12:50 steve
* Optimize ==1 when in context where x vs z doesnt matter.
*
* Revision 1.19 2002/08/27 05:39:57 steve
* Fix l-value indexing of memories and vectors so that
* an unknown (x) index causes so cell to be addresses.

27
tgt-vvp/vvp_process.c
View File

@ -17,7 +17,7 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CVS_IDENT
#ident "$Id: vvp_process.c,v 1.67 2002/09/01 00:19:35 steve Exp $"
#ident "$Id: vvp_process.c,v 1.68 2002/09/13 03:12:50 steve Exp $"
#endif
# include "vvp_priv.h"
@ -131,14 +131,14 @@ static void assign_to_memory(ivl_memory_t mem, unsigned idx,
*/
static void calculate_into_x0(ivl_expr_t expr)
{
struct vector_info vec = draw_eval_expr(expr);
struct vector_info vec = draw_eval_expr(expr, 0);
fprintf(vvp_out, " %%ix/get 0, %u, %u;\n", vec.base, vec.wid);
clr_vector(vec);
}
static void calculate_into_x1(ivl_expr_t expr)
{
struct vector_info vec = draw_eval_expr(expr);
struct vector_info vec = draw_eval_expr(expr, 0);
fprintf(vvp_out, " %%ix/get 1, %u, %u;\n", vec.base, vec.wid);
clr_vector(vec);
}
@ -217,7 +217,7 @@ static int show_stmt_assign(ivl_statement_t net)
return 0;
}
{ struct vector_info res = draw_eval_expr(rval);
{ struct vector_info res = draw_eval_expr(rval, 0);
unsigned wid = res.wid;
unsigned lidx;
unsigned cur_rbit = 0;
@ -374,7 +374,7 @@ static int show_stmt_assign_nb(ivl_statement_t net)
}
{ struct vector_info res = draw_eval_expr(rval);
{ struct vector_info res = draw_eval_expr(rval, 0);
unsigned wid = res.wid;
unsigned lidx;
unsigned cur_rbit = 0;
@ -488,7 +488,7 @@ static int show_stmt_block_named(ivl_statement_t net, ivl_scope_t scope)
static int show_stmt_case(ivl_statement_t net, ivl_scope_t sscope)
{
ivl_expr_t exp = ivl_stmt_cond_expr(net);
struct vector_info cond = draw_eval_expr(exp);
struct vector_info cond = draw_eval_expr(exp, 0);
unsigned count = ivl_stmt_case_count(net);
unsigned local_base = local_count;
@ -531,7 +531,7 @@ static int show_stmt_case(ivl_statement_t net, ivl_scope_t sscope)
/* Oh well, do this case the hard way. */
cvec = draw_eval_expr_wid(cex, cond.wid);
cvec = draw_eval_expr_wid(cex, cond.wid, 0);
assert(cvec.wid == cond.wid);
switch (ivl_statement_type(net)) {
@ -651,7 +651,7 @@ static int show_stmt_condit(ivl_statement_t net, ivl_scope_t sscope)
int rc = 0;
unsigned lab_false, lab_out;
ivl_expr_t exp = ivl_stmt_cond_expr(net);
struct vector_info cond = draw_eval_expr(exp);
struct vector_info cond = draw_eval_expr(exp, 1);
assert(cond.wid == 1);
@ -714,7 +714,7 @@ static int show_stmt_delayx(ivl_statement_t net, ivl_scope_t sscope)
ivl_expr_t exp = ivl_stmt_delay_expr(net);
ivl_statement_t stmt = ivl_stmt_sub_stmt(net);
{ struct vector_info del = draw_eval_expr(exp);
{ struct vector_info del = draw_eval_expr(exp, 0);
fprintf(vvp_out, " %%ix/get 0, %u, %u;\n", del.base, del.wid);
clr_vector(del);
}
@ -868,7 +868,7 @@ static int show_stmt_repeat(ivl_statement_t net, ivl_scope_t sscope)
int rc = 0;
unsigned lab_top = local_count++, lab_out = local_count++;
ivl_expr_t exp = ivl_stmt_cond_expr(net);
struct vector_info cnt = draw_eval_expr(exp);
struct vector_info cnt = draw_eval_expr(exp, 0);
/* Test that 0 < expr */
fprintf(vvp_out, "T_%u.%u %%cmp/u 0, %u, %u;\n", thread_count,
@ -960,7 +960,7 @@ static int show_stmt_while(ivl_statement_t net, ivl_scope_t sscope)
/* Draw the evaluation of the condition expression, and test
the result. If the expression evaluates to false, then
branch to the out label. */
cvec = draw_eval_expr(ivl_stmt_cond_expr(net));
cvec = draw_eval_expr(ivl_stmt_cond_expr(net), 1);
if (cvec.wid > 1)
cvec = reduction_or(cvec);
@ -1023,7 +1023,7 @@ static int show_system_task_call(ivl_statement_t net)
vec = (struct vector_info *)
realloc(vec, (vecs+1)*sizeof(struct vector_info));
vec[vecs] = draw_eval_expr(expr);
vec[vecs] = draw_eval_expr(expr, 0);
vecs++;
}
@ -1302,6 +1302,9 @@ int draw_func_definition(ivl_scope_t scope)
/*
* $Log: vvp_process.c,v $
* Revision 1.68 2002/09/13 03:12:50 steve
* Optimize ==1 when in context where x vs z doesnt matter.
*
* Revision 1.67 2002/09/01 00:19:35 steve
* Watch for x indices in l-value of non-blocking assignments.
*