* An association between a node and a point in time.
*/
typedef struct _loc_t {
- ir_node *irn; /**< A node. */
- unsigned time; /**< A use time (see beuses.h). */
+ ir_node *irn; /**< A node. */
+ unsigned time; /**< A use time (see beuses.h). */
+ int reloaded_value; /**< the value is a reloaded value */
} loc_t;
typedef struct _workset_t {
return p->time - q->time;
}
-static INLINE void workset_print(const workset_t *w)
+/* debug helper */
+static void workset_print(const workset_t *w)
{
int i;
for(i = 0; i < w->len; ++i) {
- ir_fprintf(stderr, "%+F %d\n", w->vals[i].irn, w->vals[i].time);
+ ir_fprintf(stderr, "%+F %d (%d)\n", w->vals[i].irn, w->vals[i].time, w->vals[i].reloaded_value);
}
+ /* avoid unused warning */
+ (void) workset_print;
}
/**
* Inserts the value @p val into the workset, iff it is not
* already contained. The workset must not be full.
*/
-static INLINE void workset_insert(belady_env_t *env, workset_t *ws, ir_node *val) {
+static INLINE void workset_insert(belady_env_t *env, workset_t *ws,
+ ir_node *val, int reloaded_value)
+{
int i;
/* check for current regclass */
if (!arch_irn_consider_in_reg_alloc(env->arch, env->cls, val)) {
- DBG((dbg, DBG_WORKSET, "Skipped %+F\n", val));
+ //DBG((dbg, DBG_WORKSET, "Skipped %+F\n", val));
return;
}
/* check if val is already contained */
- for(i=0; i<ws->len; ++i)
- if (ws->vals[i].irn == val)
+ for(i=0; i<ws->len; ++i) {
+ if (ws->vals[i].irn == val) {
+ if(!ws->vals[i].reloaded_value)
+ ws->vals[i].reloaded_value = reloaded_value;
return;
+ }
+ }
/* insert val */
assert(ws->len < env->n_regs && "Workset already full!");
- ws->vals[ws->len++].irn = val;
+ ws->vals[ws->len].irn = val;
+ ws->vals[ws->len].reloaded_value = reloaded_value;
+ ws->len++;
}
/**
if (! workset_contains(ws, val)) {
DBG((dbg, DBG_DECIDE, " insert %+F\n", val));
+
to_insert[demand++] = val;
if (is_usage) {
DBG((dbg, DBG_SPILL, "Reload %+F before %+F\n", val, env->instr));
be_add_reload(env->senv, val, env->instr, env->cls, 1);
}
- }
- else {
- assert(is_usage || "Defined value already in workset?!?");
- DBG((dbg, DBG_DECIDE, " skip %+F\n", val));
+ } else {
+ DBG((dbg, DBG_DECIDE, " %+F already in workset\n", val));
+ assert(is_usage);
}
}
- DBG((dbg, DBG_DECIDE, " demand = %d\n", demand));
+ //DBG((dbg, DBG_DECIDE, " demand = %d\n", demand));
/*
2. Make room for at least 'demand' slots
len = workset_get_length(ws);
max_allowed = env->n_regs - demand;
- DBG((dbg, DBG_DECIDE, " disposing %d values\n", ws->len - max_allowed));
-
/* Only make more free room if we do not have enough */
if (len > max_allowed) {
+ DBG((dbg, DBG_DECIDE, " disposing %d values\n", ws->len - max_allowed));
+
/* get current next-use distance */
for (i = 0; i < ws->len; ++i) {
unsigned dist = get_distance(env, env->instr, env->instr_nr, workset_get_val(ws, i), !is_usage);
for (i = max_allowed; i < ws->len; ++i) {
ir_node *irn = ws->vals[i].irn;
- DBG((dbg, DBG_DECIDE, " disposing %+F (%u)\n", irn, workset_get_time(ws, i)));
+ DBG((dbg, DBG_DECIDE, " disposing %+F (%u)\n", irn,
+ workset_get_time(ws, i)));
+
+ if(!USES_IS_INFINITE(ws->vals[i].time)
+ && !ws->vals[i].reloaded_value) {
+ be_add_spill(env->senv, irn, env->instr);
+ }
if (is_Phi(irn))
continue;
/*
3. Insert the new values into the workset
*/
- for (i = 0; i < demand; ++i)
- workset_insert(env, env->ws, to_insert[i]);
+ for (i = 0; i < demand; ++i) {
+ workset_insert(env, env->ws, to_insert[i], 1);
+ }
}
static void belady(ir_node *block, void *env);
}
/* spill all delayed phis which didn't make it into start workset */
- for (i = ARR_LEN(delayed) - 1; i >= 0; --i) {
+ for ( ; i < ARR_LEN(delayed); ++i) {
ir_node *irn = delayed[i].irn;
- if (irn && is_Phi(irn)) {
+ if (irn && is_Phi(irn) && get_nodes_block(irn) == block) {
DBG((dbg, DBG_START, " spilling delayed phi %+F\n", irn));
be_spill_phi(env->senv, irn);
}
/* allocate all values _used_ by this instruction */
workset_clear(new_vals);
for(i = 0, arity = get_irn_arity(irn); i < arity; ++i) {
- workset_insert(env, new_vals, get_irn_n(irn, i));
+ /* (note that reloaded_value is not interesting here) */
+ workset_insert(env, new_vals, get_irn_n(irn, i), 0);
}
displace(env, new_vals, 1);
foreach_out_edge(irn, edge) {
ir_node *proj = get_edge_src_irn(edge);
- workset_insert(env, new_vals, proj);
+ workset_insert(env, new_vals, proj, 0);
}
} else {
- workset_insert(env, new_vals, irn);
+ workset_insert(env, new_vals, irn, 0);
}
displace(env, new_vals, 0);
* about the set of live-ins. Thus we must adapt the
* live-outs to the live-ins at each block-border.
*/
-static void fix_block_borders(ir_node *block, void *data) {
- belady_env_t *env = data;
- workset_t *wsb;
- ir_graph *irg = get_irn_irg(block);
- ir_node *startblock = get_irg_start_block(irg);
- int i, max, iter, iter2;
-
- if(block == startblock)
- return;
+static void fix_block_borders(ir_node *block, void *data)
+{
+ ir_graph *irg = get_irn_irg(block);
+ ir_node *startblock = get_irg_start_block(irg);
+ belady_env_t *env = data;
+ workset_t *start_workset;
+ int arity;
+ int i;
+ int iter;
+
+ if(block == startblock)
+ return;
DBG((dbg, DBG_FIX, "\n"));
DBG((dbg, DBG_FIX, "Fixing %+F\n", block));
- wsb = get_block_info(block)->ws_start;
+ start_workset = get_block_info(block)->ws_start;
/* process all pred blocks */
- for (i=0, max=get_irn_arity(block); i<max; ++i) {
- ir_node *irnb, *irnp, *pred = get_Block_cfgpred_block(block, i);
- workset_t *wsp = get_block_info(pred)->ws_end;
+ arity = get_irn_arity(block);
+ for (i = 0; i < arity; ++i) {
+ ir_node *pred = get_Block_cfgpred_block(block, i);
+ workset_t *workset_pred_end = get_block_info(pred)->ws_end;
+ ir_node *node;
DBG((dbg, DBG_FIX, " Pred %+F\n", pred));
- workset_foreach(wsb, irnb, iter) {
- /* if irnb is a phi of the current block we reload
- * the corresponding argument, else irnb itself */
- if(is_Phi(irnb) && block == get_nodes_block(irnb)) {
- irnb = get_irn_n(irnb, i);
+ /* spill all values not used anymore */
+ workset_foreach(workset_pred_end, node, iter) {
+ ir_node *n2;
+ int iter2;
+ int found = 0;
+ workset_foreach(start_workset, n2, iter2) {
+ if(n2 == node) {
+ found = 1;
+ break;
+ }
+ /* note that we do not look at phi inputs, becuase the values
+ * will be either live-end and need no spill or
+ * they have other users in which must be somewhere else in the
+ * workset */
+ }
- // we might have unknowns as argument for the phi
- if(!arch_irn_consider_in_reg_alloc(env->arch, env->cls, irnb))
- continue;
+ if(!found && be_is_live_out(env->lv, pred, node)
+ && !workset_pred_end->vals[iter].reloaded_value) {
+ ir_node *insert_point
+ = be_get_end_of_block_insertion_point(pred);
+ DBG((dbg, DBG_SPILL, "Spill %+F before %+F\n", node,
+ insert_point));
+ be_add_spill(env->senv, node, insert_point);
}
+ }
- /* Unknowns are available everywhere */
- if(get_irn_opcode(irnb) == iro_Unknown)
- continue;
+ /* reload missing values in predecessors */
+ workset_foreach(start_workset, node, iter) {
+ /* if node is a phi of the current block we reload
+ * the corresponding argument, else node itself */
+ if(is_Phi(node) && block == get_nodes_block(node)) {
+ node = get_irn_n(node, i);
- /* check if irnb is in a register at end of pred */
- workset_foreach(wsp, irnp, iter2) {
- if (irnb == irnp)
- goto next_value;
+ /* we might have unknowns as argument for the phi */
+ if(!arch_irn_consider_in_reg_alloc(env->arch, env->cls, node))
+ continue;
}
- /* irnb is not in memory at the end of pred, so we have to reload it */
- DBG((dbg, DBG_FIX, " reload %+F\n", irnb));
- DBG((dbg, DBG_SPILL, "Reload %+F before %+F,%d\n", irnb, block, i));
- be_add_reload_on_edge(env->senv, irnb, block, i, env->cls, 1);
+ /* check if node is in a register at end of pred */
+ if(workset_contains(workset_pred_end, node))
+ continue;
-next_value:
- /*epsilon statement :)*/;
+ /* node is not in memory at the end of pred -> reload it */
+ DBG((dbg, DBG_FIX, " reload %+F\n", node));
+ DBG((dbg, DBG_SPILL, "Reload %+F before %+F,%d\n", node, block, i));
+ be_add_reload_on_edge(env->senv, node, block, i, env->cls, 1);
}
}
}
ir_graph *irg = be_get_birg_irg(birg);
int n_regs;
- /* some special classes contain only ignore regs, nothing to do then */
n_regs = cls->n_regs - be_put_ignore_regs(birg, cls, NULL);
- if(n_regs == 0)
- return;
-
be_liveness_assure_sets(be_assure_liveness(birg));
/* construct control flow loop tree */
irg_block_walk_graph(irg, NULL, belady, &env);
/* belady was block-local, fix the global flow by adding reloads on the edges */
irg_block_walk_graph(irg, fix_block_borders, NULL, &env);
+
+ be_end_uses(env.uses);
+ be_free_loop_pressure(env.loop_ana);
+ obstack_free(&env.ob, NULL);
+
/* Insert spill/reload nodes into the graph and fix usages */
be_insert_spills_reloads(env.senv);
/* clean up */
if(spill_env == NULL)
be_delete_spill_env(env.senv);
- be_end_uses(env.uses);
- be_free_loop_pressure(env.loop_ana);
- obstack_free(&env.ob, NULL);
}
void be_init_spillbelady(void)
projects / libfirm / blobdiff