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Generate %muli instructions when possible.

This commit is contained in:
steve 2002-05-31 20:04:57 +00:00
parent 1ce50993f0
commit cba5a22714
1 changed files with 70 additions and 14 deletions
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84
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
*/
#if !defined(WINNT)
#ident "$Id: eval_expr.c,v 1.61 2002/05/30 01:57:23 steve Exp $"
#ident "$Id: eval_expr.c,v 1.62 2002/05/31 20:04:57 steve Exp $"
#endif
# include "vvp_priv.h"
@ -554,25 +554,40 @@ static int number_is_unknown(ivl_expr_t ex)
return 0;
}
static struct vector_info draw_add_immediate(ivl_expr_t le,
ivl_expr_t re,
unsigned wid)
/*
* This function returns TRUE if the number can be represented in a
* 16bit immediate value. This amounts to looking for non-zero bits
* above bitX. The maximum size of the immediate may vary, so use
* lim_wid at the width limit to use.
*/
static int number_is_immediate(ivl_expr_t ex, unsigned lim_wid)
{
const char*bits;
unsigned idx;
assert(ivl_expr_type(ex) == IVL_EX_NUMBER);
bits = ivl_expr_bits(ex);
for (idx = lim_wid ; idx < ivl_expr_width(ex) ; idx += 1)
if (bits[idx] != '0')
return 0;
return 1;
}
static unsigned long get_number_immediate(ivl_expr_t ex)
{
struct vector_info lv;
unsigned long imm = 0;
unsigned idx;
lv = draw_eval_expr_wid(le, wid);
assert(lv.wid == wid);
switch (ivl_expr_type(re)) {
switch (ivl_expr_type(ex)) {
case IVL_EX_ULONG:
imm = ivl_expr_uvalue(re);
imm = ivl_expr_uvalue(ex);
break;
case IVL_EX_NUMBER: {
const char*bits = ivl_expr_bits(re);
unsigned nbits = ivl_expr_width(re);
const char*bits = ivl_expr_bits(ex);
unsigned nbits = ivl_expr_width(ex);
for (idx = 0 ; idx < nbits ; idx += 1) switch (bits[idx]){
case '0':
break;
@ -589,6 +604,21 @@ static struct vector_info draw_add_immediate(ivl_expr_t le,
assert(0);
}
return imm;
}
static struct vector_info draw_add_immediate(ivl_expr_t le,
ivl_expr_t re,
unsigned wid)
{
struct vector_info lv;
unsigned long imm;
lv = draw_eval_expr_wid(le, wid);
assert(lv.wid == wid);
imm = get_number_immediate(re);
/* Now generate enough %addi instructions to add the entire
immediate value to the destination. The adds are done 16
bits at a time, but 17 bits are done to push the carry into
@ -613,6 +643,23 @@ static struct vector_info draw_add_immediate(ivl_expr_t le,
return lv;
}
static struct vector_info draw_mul_immediate(ivl_expr_t le,
ivl_expr_t re,
unsigned wid)
{
struct vector_info lv;
unsigned long imm;
lv = draw_eval_expr_wid(le, wid);
assert(lv.wid == wid);
imm = get_number_immediate(re);
fprintf(vvp_out, " %%muli %u, %lu, %u;\n", lv.base, imm, lv.wid);
return lv;
}
static struct vector_info draw_binary_expr_arith(ivl_expr_t exp, unsigned wid)
{
ivl_expr_t le = ivl_expr_oper1(exp);
@ -629,10 +676,16 @@ static struct vector_info draw_binary_expr_arith(ivl_expr_t exp, unsigned wid)
if ((ivl_expr_opcode(exp) == '+')
&& (ivl_expr_type(re) == IVL_EX_NUMBER)
&& (ivl_expr_width(re) <= 8 * sizeof(unsigned long))
&& (! number_is_unknown(re)))
&& (! number_is_unknown(re))
&& number_is_immediate(re, 8*sizeof(unsigned long)))
return draw_add_immediate(le, re, wid);
if ((ivl_expr_opcode(exp) == '*')
&& (ivl_expr_type(re) == IVL_EX_NUMBER)
&& (! number_is_unknown(re))
&& 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);
@ -1595,6 +1648,9 @@ struct vector_info draw_eval_expr(ivl_expr_t exp)
/*
* $Log: eval_expr.c,v $
* Revision 1.62 2002/05/31 20:04:57 steve
* Generate %muli instructions when possible.
*
* Revision 1.61 2002/05/30 01:57:23 steve
* Use addi with wide immediate values.
*