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single bit optimization for != in expressions, 

and expand ++ and != results if needed.
This commit is contained in:
steve 2002-09-13 04:09:51 +00:00
parent 28725d0d74
commit fb0383d2bd
1 changed files with 21 additions and 1 deletions
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22
tgt-vvp/eval_expr.c
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@ -17,7 +17,7 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/ */
#ifdef HAVE_CVS_IDENT #ifdef HAVE_CVS_IDENT
#ident "$Id: eval_expr.c,v 1.76 2002/09/13 03:12:50 steve Exp $" #ident "$Id: eval_expr.c,v 1.77 2002/09/13 04:09:51 steve Exp $"
#endif #endif
# include "vvp_priv.h" # include "vvp_priv.h"
@ -211,6 +211,12 @@ static struct vector_info draw_eq_immediate(ivl_expr_t exp, unsigned ewid,
break; break;
case 'n': /* != */ case 'n': /* != */
/* If this is a single bit being compared to 0, and the
output doesn't care about x vs z, then just return
the value itself. */
if (xz_ok_flag && (lv.wid == 1) && (imm == 0))
break;
fprintf(vvp_out, " %%cmpi/u %u, %lu, %u;\n", fprintf(vvp_out, " %%cmpi/u %u, %lu, %u;\n",
lv.base, imm, wid); lv.base, imm, wid);
clr_vector(lv); clr_vector(lv);
@ -233,6 +239,16 @@ static struct vector_info draw_eq_immediate(ivl_expr_t exp, unsigned ewid,
lv.wid = ewid; lv.wid = ewid;
if (ewid > 1) if (ewid > 1)
fprintf(vvp_out, " %%mov %u, 0, %u;\n", base+1, ewid-1); fprintf(vvp_out, " %%mov %u, 0, %u;\n", base+1, ewid-1);
} else if (lv.wid < ewid) {
unsigned short base = allocate_vector(ewid);
clr_vector(lv);
fprintf(vvp_out, " %%mov %u, %u, %u;\n", base,
lv.base, lv.wid);
fprintf(vvp_out, " %%mov %u, 0, %u;\n",
base+lv.wid, ewid-lv.wid);
lv.base = base;
lv.wid = ewid;
} }
return lv; return lv;
@ -1818,6 +1834,10 @@ struct vector_info draw_eval_expr(ivl_expr_t exp, int xz_ok_flag)
/* /*
* $Log: eval_expr.c,v $ * $Log: eval_expr.c,v $
* Revision 1.77 2002/09/13 04:09:51 steve
* single bit optimization for != in expressions,
* and expand ++ and != results if needed.
*
* Revision 1.76 2002/09/13 03:12:50 steve * Revision 1.76 2002/09/13 03:12:50 steve
* Optimize ==1 when in context where x vs z doesnt matter. * Optimize ==1 when in context where x vs z doesnt matter.
* *