optimize: only write to state when clearing optimizer data

The next patch will add to the TCG optimizer a field that should be
non-zero in the default case.  Thus, replace the memset of the
temps array with a loop.  Only the state field has to be up-to-date,
because others are not used except if the state is TCG_TEMP_COPY
or TCG_TEMP_CONST.

[rth: Extracted the loop to a function.]

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
This commit is contained in:
Paolo Bonzini 2013-01-11 15:42:51 -08:00 committed by Blue Swirl
parent 75f0585f17
commit d193a14a2c

View file

@ -65,6 +65,15 @@ static void reset_temp(TCGArg temp)
temps[temp].state = TCG_TEMP_UNDEF;
}
/* Reset all temporaries, given that there are NB_TEMPS of them. */
static void reset_all_temps(int nb_temps)
{
int i;
for (i = 0; i < nb_temps; i++) {
temps[i].state = TCG_TEMP_UNDEF;
}
}
static int op_bits(TCGOpcode op)
{
const TCGOpDef *def = &tcg_op_defs[op];
@ -482,7 +491,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
nb_temps = s->nb_temps;
nb_globals = s->nb_globals;
memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
reset_all_temps(nb_temps);
nb_ops = tcg_opc_ptr - s->gen_opc_buf;
gen_args = args;
@ -768,7 +777,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
tmp = do_constant_folding_cond(op, args[0], args[1], args[2]);
if (tmp != 2) {
if (tmp) {
memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
reset_all_temps(nb_temps);
s->gen_opc_buf[op_index] = INDEX_op_br;
gen_args[0] = args[3];
gen_args += 1;
@ -861,7 +870,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
tmp = do_constant_folding_cond2(&args[0], &args[2], args[4]);
if (tmp != 2) {
if (tmp) {
memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
reset_all_temps(nb_temps);
s->gen_opc_buf[op_index] = INDEX_op_br;
gen_args[0] = args[5];
gen_args += 1;
@ -875,7 +884,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
&& temps[args[3]].val == 0) {
/* Simplify LT/GE comparisons vs zero to a single compare
vs the high word of the input. */
memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
reset_all_temps(nb_temps);
s->gen_opc_buf[op_index] = INDEX_op_brcond_i32;
gen_args[0] = args[1];
gen_args[1] = args[3];
@ -940,7 +949,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
We trash everything if the operation is the end of a basic
block, otherwise we only trash the output args. */
if (def->flags & TCG_OPF_BB_END) {
memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
reset_all_temps(nb_temps);
} else {
for (i = 0; i < def->nb_oargs; i++) {
reset_temp(args[i]);