tcg/optimize: Improve find_better_copy

Prefer TEMP_CONST over anything else.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2020-04-23 09:02:23 -07:00
parent c0522136ad
commit 4c868ce645
1 changed files with 12 additions and 15 deletions

View File

@ -122,31 +122,28 @@ static void init_arg_info(TempOptInfo *infos,
static TCGTemp *find_better_copy(TCGContext *s, TCGTemp *ts)
{
TCGTemp *i;
TCGTemp *i, *g, *l;
/* If this is already a global, we can't do better. */
if (ts->kind >= TEMP_GLOBAL) {
/* If this is already readonly, we can't do better. */
if (temp_readonly(ts)) {
return ts;
}
/* Search for a global first. */
g = l = NULL;
for (i = ts_info(ts)->next_copy; i != ts; i = ts_info(i)->next_copy) {
if (i->kind >= TEMP_GLOBAL) {
if (temp_readonly(i)) {
return i;
}
}
/* If it is a temp, search for a temp local. */
if (ts->kind == TEMP_NORMAL) {
for (i = ts_info(ts)->next_copy; i != ts; i = ts_info(i)->next_copy) {
if (i->kind >= TEMP_LOCAL) {
return i;
} else if (i->kind > ts->kind) {
if (i->kind == TEMP_GLOBAL) {
g = i;
} else if (i->kind == TEMP_LOCAL) {
l = i;
}
}
}
/* Failure to find a better representation, return the same temp. */
return ts;
/* If we didn't find a better representation, return the same temp. */
return g ? g : l ? l : ts;
}
static bool ts_are_copies(TCGTemp *ts1, TCGTemp *ts2)