Commit 83856b6a authored by Matthias Braun's avatar Matthias Braun
Browse files

change lower_switch to work on tarvals instead of int

parent 59dd91cd
......@@ -56,8 +56,8 @@ typedef struct case_data_t {
typedef struct switch_info_t {
ir_node *switchn;
long switch_min;
long switch_max;
ir_tarval *switch_min;
ir_tarval *switch_max;
ir_node *default_block;
unsigned num_cases;
case_data_t *cases;
......@@ -67,31 +67,26 @@ typedef struct switch_info_t {
/**
* analyze enough to decide if we should lower the switch
*/
static bool analyse_switch0(switch_info_t *info, ir_node *switchn)
static void analyse_switch0(switch_info_t *info, ir_node *switchn)
{
const ir_switch_table *table = get_Switch_table(switchn);
size_t n_entries = ir_switch_table_get_n_entries(table);
long switch_min = LONG_MAX;
long switch_max = LONG_MIN;
unsigned num_cases = 0;
size_t e;
for (e = 0; e < n_entries; ++e) {
const ir_switch_table *table = get_Switch_table(switchn);
size_t n_entries = ir_switch_table_get_n_entries(table);
ir_mode *mode = get_irn_mode(get_Switch_selector(switchn));
ir_tarval *switch_min = get_mode_max(mode);
ir_tarval *switch_max = get_mode_min(mode);
unsigned num_cases = 0;
for (size_t e = 0; e < n_entries; ++e) {
const ir_switch_table_entry *entry
= ir_switch_table_get_entry_const(table, e);
long minval;
long maxval;
if (entry->pn == 0)
continue;
if (!tarval_is_long(entry->min) || !tarval_is_long(entry->max))
return false;
minval = get_tarval_long(entry->min);
maxval = get_tarval_long(entry->max);
if (minval < switch_min)
switch_min = minval;
if (maxval > switch_max)
switch_max = maxval;
if (tarval_cmp(entry->min, switch_min) == ir_relation_less)
switch_min = entry->min;
if (tarval_cmp(entry->max, switch_max) == ir_relation_greater)
switch_max = entry->max;
++num_cases;
}
......@@ -99,7 +94,6 @@ static bool analyse_switch0(switch_info_t *info, ir_node *switchn)
info->switch_min = switch_min;
info->switch_max = switch_max;
info->num_cases = num_cases;
return true;
}
static int casecmp(const void *a, const void *b)
......@@ -205,35 +199,38 @@ static void normalize_table(ir_node *switchn, ir_mode *new_mode,
*/
static void normalize_switch(switch_info_t *info)
{
ir_node *switchn = info->switchn;
ir_graph *irg = get_irn_irg(switchn);
ir_node *block = get_nodes_block(switchn);
ir_node *selector = get_Switch_selector(switchn);
ir_mode *mode = get_irn_mode(selector);
ir_tarval *delta = NULL;
bool change_mode = false;
ir_node *switchn = info->switchn;
ir_graph *irg = get_irn_irg(switchn);
ir_node *block = get_nodes_block(switchn);
ir_node *selector = get_Switch_selector(switchn);
ir_mode *switch_mode = get_irn_mode(selector);
ir_mode *mode = switch_mode;
ir_tarval *delta = NULL;
bool needs_normalize = false;
ir_tarval *min = info->switch_min;
if (mode_is_signed(mode)) {
mode = find_unsigned_mode(mode);
selector = new_r_Conv(block, selector, mode);
change_mode = true;
mode = find_unsigned_mode(mode);
selector = new_r_Conv(block, selector, mode);
min = tarval_convert_to(min, mode);
needs_normalize = true;
info->switch_max = tarval_convert_to(info->switch_max, mode);
}
/* normalize so switch_min is at 0 */
if (info->switch_min != 0) {
dbg_info *dbgi = get_irn_dbg_info(switchn);
ir_node *min_const;
delta = new_tarval_from_long(info->switch_min, mode);
if (min != get_mode_null(mode)) {
ir_node *min_const = new_r_Const(irg, min);
dbg_info *dbgi = get_irn_dbg_info(switchn);
selector = new_rd_Sub(dbgi, block, selector, min_const, mode);
min_const = new_r_Const(irg, delta);
selector = new_rd_Sub(dbgi, block, selector, min_const, mode);
info->switch_max = tarval_sub(info->switch_max, min, mode);
info->switch_min = get_mode_null(mode);
delta = min;
info->switch_max -= info->switch_min;
info->switch_min = 0;
needs_normalize = true;
}
if (delta != NULL || change_mode) {
if (needs_normalize) {
set_Switch_selector(switchn, selector);
normalize_table(switchn, mode, delta);
}
......@@ -337,7 +334,6 @@ static void create_out_of_bounds_check(switch_info_t *info)
dbg_info *dbgi = get_irn_dbg_info(switchn);
ir_node *selector = get_Switch_selector(switchn);
ir_node *block = get_nodes_block(switchn);
ir_mode *cmp_mode = get_irn_mode(selector);
ir_node **default_preds = NEW_ARR_F(ir_node*, 0);
ir_node *default_block = NULL;
ir_node *max_const;
......@@ -351,10 +347,10 @@ static void create_out_of_bounds_check(switch_info_t *info)
ir_node *proj;
size_t n_default_preds;
assert(info->switch_min == 0);
assert(tarval_is_null(info->switch_min));
/* check for out-of-bounds */
max_const = new_r_Const_long(irg, cmp_mode, info->switch_max);
max_const = new_r_Const(irg, info->switch_max);
cmp = new_rd_Cmp(dbgi, block, selector, max_const, ir_relation_less_equal);
oob_cond = new_rd_Cond(dbgi, block, cmp);
proj_true = new_r_Proj(oob_cond, mode_X, pn_Cond_true);
......@@ -410,9 +406,6 @@ static void find_switch_nodes(ir_node *block, void *ctx)
ir_node *projx;
ir_node *switchn;
switch_info_t info;
unsigned long spare;
bool lower_switch = false;
bool could_analyze;
/* because we split critical blocks only blocks with 1 predecessors may
* contain Proj->Cond nodes */
......@@ -432,22 +425,22 @@ static void find_switch_nodes(ir_node *block, void *ctx)
return;
ir_nodeset_insert(&env->processed, switchn);
could_analyze = analyse_switch0(&info, switchn);
/* the code can't handle values which are not representable in the host */
if (!could_analyze) {
ir_fprintf(stderr, "libfirm warning: Couldn't analyse %+F (this could go wrong in the backend)\n", switchn);
return;
}
analyse_switch0(&info, switchn);
/*
* Here we have: num_cases and [switch_min, switch_max] interval.
* We do an if-cascade if there are too many spare numbers.
*/
spare = (unsigned long) info.switch_max
- (unsigned long) info.switch_min
- (unsigned long) info.num_cases + 1;
lower_switch |= spare >= env->spare_size;
lower_switch |= info.num_cases <= env->small_switch;
ir_mode *mode = get_irn_mode(get_Switch_selector(switchn));
ir_tarval *spare = tarval_sub(info.switch_max, info.switch_min, mode);
mode = find_unsigned_mode(mode);
spare = tarval_convert_to(spare, mode);
ir_tarval *num_cases_minus_one
= new_tarval_from_long(info.num_cases-1, mode);
spare = tarval_sub(spare, num_cases_minus_one, mode);
ir_tarval *spare_size = new_tarval_from_long(env->spare_size, mode);
bool lower_switch = (info.num_cases <= env->small_switch
|| (tarval_cmp(spare, spare_size) & ir_relation_greater_equal));
if (!lower_switch) {
/* we won't decompose the switch. But we might have to add
......@@ -463,9 +456,9 @@ static void find_switch_nodes(ir_node *block, void *ctx)
analyse_switch1(&info);
/* Now create the if cascade */
env->changed = true;
env->changed = true;
info.defusers = NEW_ARR_F(ir_node*, 0);
block = get_nodes_block(switchn);
block = get_nodes_block(switchn);
create_if_cascade(&info, block, info.cases, info.num_cases);
/* Connect new default case users */
......
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