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Assure that operands are the correct width.

This commit is contained in:
steve 2001-03-23 01:10:24 +00:00
parent 548ff4f89a
commit c2dc3fe5c3
1 changed files with 107 additions and 21 deletions
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128
tgt-vvp/eval_expr.c
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@ -17,12 +17,14 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#if !defined(WINNT)
#ident "$Id: eval_expr.c,v 1.1 2001/03/22 05:06:21 steve Exp $"
#ident "$Id: eval_expr.c,v 1.2 2001/03/23 01:10:24 steve Exp $"
#endif
# include "vvp_priv.h"
# include <assert.h>
struct vector_info draw_eval_expr_wid(ivl_expr_t exp, unsigned wid);
static unsigned char allocation_map[0x10000/8];
static inline int peek_bit(unsigned addr)
@ -75,15 +77,21 @@ static unsigned short allocate_vector(unsigned short wid)
return base;
}
/*
* The draw_eval_expr() function draws code to evaluate the passed
* expression, then returns the location and width of the result.
*/
static struct vector_info draw_binary_expr(ivl_expr_t exp)
static struct vector_info draw_binary_expr_eq(ivl_expr_t exp)
{
struct vector_info lv = draw_eval_expr(ivl_expr_oper1(exp));
struct vector_info rv = draw_eval_expr(ivl_expr_oper2(exp));
ivl_expr_t le = ivl_expr_oper1(exp);
ivl_expr_t re = ivl_expr_oper2(exp);
struct vector_info lv;
struct vector_info rv;
unsigned 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);
switch (ivl_expr_opcode(exp)) {
case 'e': /* == */
@ -115,17 +123,73 @@ static struct vector_info draw_binary_expr(ivl_expr_t exp)
return lv;
}
static struct vector_info draw_number_expr(ivl_expr_t exp)
static struct vector_info draw_binary_expr(ivl_expr_t exp, unsigned wid)
{
struct vector_info rv;
switch (ivl_expr_opcode(exp)) {
case 'e': /* == */
case 'n': /* != */
assert(wid == 1);
rv = draw_binary_expr_eq(exp);
break;
default:
assert(0);
}
return rv;
}
/*
* A number in an expression is made up by copying constant bits into
* the allocated vector.
*/
static struct vector_info draw_number_expr(ivl_expr_t exp, unsigned wid)
{
unsigned idx;
unsigned wid = ivl_expr_width(exp);
struct vector_info res;
const char*bits = ivl_expr_bits(exp);
struct vector_info res;
res.base = allocate_vector(wid);
res.wid = wid;
for (idx = 0 ; idx < wid ; idx += 1) {
assert(ivl_expr_width(exp) >= wid);
/* If all the bits of the number have the same value, then we
can use a constant bit. There is no need to allocate wr
bits, and there is no need to generate any code. */
for (idx = 1 ; idx < res.wid ; idx += 1) {
if (bits[idx] != bits[0])
break;
}
if (idx == res.wid) {
switch (bits[0]) {
case '0':
res.base = 0;
break;
case '1':
res.base = 1;
break;
case 'x':
res.base = 2;
break;
case 'z':
res.base = 3;
break;
}
return res;
}
/* The number value needs to be represented as an allocated
vector. Allocate the vector and use %mov instructions to
load the constant bit values. */
res.base = allocate_vector(wid);
idx = 0;
while (idx < wid) {
unsigned cnt;
char src = '?';
switch (bits[idx]) {
case '0':
@ -142,30 +206,44 @@ static struct vector_info draw_number_expr(ivl_expr_t exp)
break;
}
fprintf(vvp_out, " %%mov %u, %c, 1;\n", res.base+idx, src);
for (cnt = 1 ; idx+cnt < wid ; cnt += 1)
if (bits[idx+cnt] != bits[idx])
break;
fprintf(vvp_out, " %%mov %u, %c, %u;\n",
res.base+idx, src, cnt);
idx += cnt;
}
return res;
}
static struct vector_info draw_signal_expr(ivl_expr_t exp)
static struct vector_info draw_signal_expr(ivl_expr_t exp, unsigned wid)
{
unsigned idx;
unsigned wid = ivl_expr_width(exp);
unsigned swid = ivl_expr_width(exp);
const char*name = ivl_expr_name(exp);
struct vector_info res;
if (swid > wid)
swid = wid;
res.base = allocate_vector(wid);
res.wid = wid;
for (idx = 0 ; idx < wid ; idx += 1)
for (idx = 0 ; idx < swid ; idx += 1)
fprintf(vvp_out, " %%load %u, V_%s[%u];\n",
res.base+idx, name, idx);
/* Pad the signal value with zeros. */
if (swid < wid)
fprintf(vvp_out, " %%mov %u, 0, %u;\n",
res.base+swid, wid-swid);
return res;
}
struct vector_info draw_eval_expr(ivl_expr_t exp)
struct vector_info draw_eval_expr_wid(ivl_expr_t exp, unsigned wid)
{
struct vector_info res;
@ -178,23 +256,31 @@ struct vector_info draw_eval_expr(ivl_expr_t exp)
break;
case IVL_EX_BINARY:
res = draw_binary_expr(exp);
res = draw_binary_expr(exp, wid);
break;
case IVL_EX_NUMBER:
res = draw_number_expr(exp);
res = draw_number_expr(exp, wid);
break;
case IVL_EX_SIGNAL:
res = draw_signal_expr(exp);
res = draw_signal_expr(exp, wid);
break;
}
return res;
}
struct vector_info draw_eval_expr(ivl_expr_t exp)
{
return draw_eval_expr_wid(exp, ivl_expr_width(exp));
}
/*
* $Log: eval_expr.c,v $
* Revision 1.2 2001/03/23 01:10:24 steve
* Assure that operands are the correct width.
*
* Revision 1.1 2001/03/22 05:06:21 steve
* Geneate code for conditional statements.
*