#endif
#include "obst.h"
-#include "set.h"
-#include "pset.h"
#include "irprintf_t.h"
#include "irgraph.h"
#include "irnode.h"
#include "iredges_t.h"
#include "ircons_t.h"
#include "irprintf.h"
+#include "irnodeset.h"
#include "xmalloc.h"
+#include "pdeq.h"
#include "beutil.h"
#include "bearch_t.h"
#include "beirg_t.h"
#include "bemodule.h"
-#define DBG_SPILL 1
-#define DBG_WSETS 2
-#define DBG_FIX 4
-#define DBG_DECIDE 8
-#define DBG_START 16
-#define DBG_SLOTS 32
-#define DBG_TRACE 64
+#define DBG_SPILL 1
+#define DBG_WSETS 2
+#define DBG_FIX 4
+#define DBG_DECIDE 8
+#define DBG_START 16
+#define DBG_SLOTS 32
+#define DBG_TRACE 64
#define DBG_WORKSET 128
DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
+typedef enum {
+ value_not_reloaded, /* the value has not been reloaded */
+ value_partially_reloaded, /* the value has been reloaded on some paths */
+ value_reloaded /* the value has been reloaded on all paths */
+} reloaded_state_t;
+
/**
* 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). */
- int reloaded_value; /**< the value is a reloaded value */
+typedef struct loc_t {
+ ir_node *node;
+ unsigned time; /**< A use time (see beuses.h). */
+ reloaded_state_t reloaded; /**< the value is a reloaded value */
} loc_t;
typedef struct _workset_t {
- int len; /**< current length */
- loc_t vals[0]; /**< inlined array of the values/distances in this working set */
+ int len; /**< current length */
+ loc_t vals[0]; /**< inlined array of the values/distances in this working set */
} workset_t;
-typedef struct _belady_env_t {
- struct obstack ob;
- const arch_env_t *arch;
- const arch_register_class_t *cls;
- be_lv_t *lv;
- be_loopana_t *loop_ana;
- int n_regs; /** number of regs in this reg-class */
-
- workset_t *ws; /**< the main workset used while processing a block. ob-allocated */
- be_uses_t *uses; /**< env for the next-use magic */
- ir_node *instr; /**< current instruction */
- unsigned instr_nr; /**< current instruction number (relative to block start) */
- pset *used;
-
- spill_env_t *senv; /**< see bespill.h */
-} belady_env_t;
+static struct obstack obst;
+static const arch_env_t *arch_env;
+static const arch_register_class_t *cls;
+static const be_lv_t *lv;
+static be_loopana_t *loop_ana;
+static int n_regs;
+static workset_t *ws; /**< the main workset used while
+ processing a block. */
+static be_uses_t *uses; /**< env for the next-use magic */
+static ir_node *instr; /**< current instruction */
+static unsigned instr_nr; /**< current instruction number
+ (relative to block start) */
+static ir_nodeset_t used;
+static spill_env_t *senv; /**< see bespill.h */
+static pdeq *worklist;
static int loc_compare(const void *a, const void *b)
{
return p->time - q->time;
}
-/* debug helper */
-static void workset_print(const workset_t *w)
+void workset_print(const workset_t *w)
{
int i;
for(i = 0; i < w->len; ++i) {
- ir_fprintf(stderr, "%+F %d (%d)\n", w->vals[i].irn, w->vals[i].time, w->vals[i].reloaded_value);
+ ir_fprintf(stderr, "%+F %d\n", w->vals[i].node, w->vals[i].time);
}
- /* avoid unused warning */
- (void) workset_print;
}
/**
* Alloc a new workset on obstack @p ob with maximum size @p max
*/
-static INLINE workset_t *new_workset(belady_env_t *env, struct obstack *ob) {
+static workset_t *new_workset(void)
+{
workset_t *res;
- size_t size = sizeof(*res) + (env->n_regs)*sizeof(res->vals[0]);
- res = obstack_alloc(ob, size);
+ size_t size = sizeof(*res) + n_regs * sizeof(res->vals[0]);
+
+ res = obstack_alloc(&obst, size);
memset(res, 0, size);
return res;
}
/**
- * Alloc a new instance on obstack and make it equal to @param ws
+ * Alloc a new instance on obstack and make it equal to @param workset
*/
-static INLINE workset_t *workset_clone(belady_env_t *env, struct obstack *ob, workset_t *ws) {
+static workset_t *workset_clone(workset_t *workset)
+{
workset_t *res;
- size_t size = sizeof(*res) + (env->n_regs)*sizeof(res->vals[0]);
- res = obstack_alloc(ob, size);
- memcpy(res, ws, size);
+ size_t size = sizeof(*res) + n_regs * sizeof(res->vals[0]);
+ res = obstack_alloc(&obst, size);
+ memcpy(res, workset, size);
return res;
}
/**
- * Do NOT alloc anything. Make @param tgt equal to @param src.
- * returns @param tgt for convenience
+ * Copy workset @param src to @param tgt
*/
-static INLINE workset_t *workset_copy(belady_env_t *env, workset_t *tgt, workset_t *src) {
- size_t size = sizeof(*src) + (env->n_regs)*sizeof(src->vals[0]);
- memcpy(tgt, src, size);
- return tgt;
+static void workset_copy(workset_t *dest, const workset_t *src)
+{
+ size_t size = sizeof(*src) + n_regs * sizeof(src->vals[0]);
+ memcpy(dest, src, size);
}
/**
* @param count locations given at memory @param locs.
* Set the length of @param ws to count.
*/
-static INLINE void workset_bulk_fill(workset_t *workset, int count, const loc_t *locs) {
+static void workset_bulk_fill(workset_t *workset, int count, const loc_t *locs)
+{
workset->len = count;
memcpy(&(workset->vals[0]), locs, count * sizeof(locs[0]));
}
* 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, int reloaded_value)
+static void workset_insert(workset_t *workset, ir_node *val, int reloaded)
{
- int i;
+ loc_t *loc;
+ 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));
- return;
- }
+ assert(arch_irn_consider_in_reg_alloc(arch_env, cls, val));
/* check if val is already contained */
- 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;
+ for (i = 0; i < workset->len; ++i) {
+ loc = &workset->vals[i];
+ if (loc->node == val) {
+ if(!loc->reloaded) {
+ loc->reloaded = reloaded;
+ }
return;
}
}
/* insert val */
- assert(ws->len < env->n_regs && "Workset already full!");
- ws->vals[ws->len].irn = val;
- ws->vals[ws->len].reloaded_value = reloaded_value;
- ws->vals[ws->len].time = 6666;
- ws->len++;
+ assert(workset->len < n_regs && "Workset already full!");
+ loc = &workset->vals[workset->len];
+ loc->node = val;
+ loc->reloaded = reloaded;
+ loc->time = 6666; /* undefined yet */
+ workset->len++;
}
/**
* Removes all entries from this workset
*/
-static INLINE void workset_clear(workset_t *ws) {
- ws->len = 0;
+static void workset_clear(workset_t *workset)
+{
+ workset->len = 0;
}
/**
* Removes the value @p val from the workset if present.
*/
-static INLINE void workset_remove(workset_t *ws, ir_node *val) {
+static INLINE void workset_remove(workset_t *workset, ir_node *val)
+{
int i;
- for(i=0; i<ws->len; ++i) {
- if (ws->vals[i].irn == val) {
- ws->vals[i] = ws->vals[--ws->len];
+ for(i = 0; i < workset->len; ++i) {
+ if (workset->vals[i].node == val) {
+ workset->vals[i] = workset->vals[--workset->len];
return;
}
}
}
-static INLINE int workset_contains(const workset_t *ws, const ir_node *val) {
+static INLINE int workset_contains(const workset_t *ws, const ir_node *val)
+{
int i;
+
for(i=0; i<ws->len; ++i) {
- if (ws->vals[i].irn == val)
+ if (ws->vals[i].node == val)
return 1;
}
* @p i An integer for internal use
*/
#define workset_foreach(ws, v, i) for(i=0; \
- v=(i < ws->len) ? ws->vals[i].irn : NULL, i < ws->len; \
+ v=(i < ws->len) ? ws->vals[i].node : NULL, i < ws->len; \
++i)
#define workset_set_time(ws, i, t) (ws)->vals[i].time=t
#define workset_get_time(ws, i) (ws)->vals[i].time
#define workset_set_length(ws, length) (ws)->len = length
#define workset_get_length(ws) ((ws)->len)
-#define workset_get_val(ws, i) ((ws)->vals[i].irn)
+#define workset_get_val(ws, i) ((ws)->vals[i].node)
#define workset_sort(ws) qsort((ws)->vals, (ws)->len, sizeof((ws)->vals[0]), loc_compare);
-typedef struct _block_info_t {
- workset_t *ws_start, *ws_end;
- int processed;
+typedef struct _block_info_t
+{
+ workset_t *start_workset;
+ workset_t *end_workset;
} block_info_t;
-static INLINE void *new_block_info(struct obstack *ob) {
- block_info_t *res = obstack_alloc(ob, sizeof(*res));
- res->ws_start = NULL;
- res->ws_end = NULL;
- res->processed = 0;
+static void *new_block_info(void)
+{
+ block_info_t *res = obstack_alloc(&obst, sizeof(res[0]));
+ memset(res, 0, sizeof(res[0]));
return res;
}
/**
* @return The distance to the next use or 0 if irn has dont_spill flag set
*/
-static INLINE unsigned get_distance(belady_env_t *env, ir_node *from, unsigned from_step, const ir_node *def, int skip_from_uses)
+static INLINE unsigned get_distance(ir_node *from, unsigned from_step,
+ const ir_node *def, int skip_from_uses)
{
be_next_use_t use;
- int flags = arch_irn_get_flags(env->arch, def);
+ int flags = arch_irn_get_flags(arch_env, def);
unsigned time;
assert(! (flags & arch_irn_flags_ignore));
- use = be_get_next_use(env->uses, from, from_step, def, skip_from_uses);
+ use = be_get_next_use(uses, from, from_step, def, skip_from_uses);
if(USES_IS_INFINITE(use.time))
return USES_INFINITY;
return 0;
time = use.time;
- time += be_get_reload_costs_no_weight(env->senv, def, use.before) * 10;
+ time += be_get_reload_costs_no_weight(senv, def, use.before) * 10;
return use.time;
}
* @p is_usage indicates that the values in new_vals are used (not defined)
* In this case reloads must be performed
*/
-static void displace(belady_env_t *env, workset_t *new_vals, int is_usage) {
+static void displace(workset_t *new_vals, int is_usage)
+{
ir_node *val;
int i, len, max_allowed, demand, iter;
- workset_t *ws = env->ws;
- ir_node **to_insert = alloca(env->n_regs * sizeof(*to_insert));
+ ir_node **to_insert = alloca(n_regs * sizeof(to_insert[0]));
/*
1. Identify the number of needed slots and the values to reload
workset_foreach(new_vals, val, iter) {
/* mark value as used */
if (is_usage)
- pset_insert_ptr(env->used, val);
+ ir_nodeset_insert(&used, val);
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);
+ DBG((dbg, DBG_SPILL, "Reload %+F before %+F\n", val, instr));
+ be_add_reload(senv, val, instr, cls, 1);
}
} else {
DBG((dbg, DBG_DECIDE, " %+F already in workset\n", val));
2. Make room for at least 'demand' slots
*/
len = workset_get_length(ws);
- max_allowed = env->n_regs - demand;
+ max_allowed = n_regs - demand;
/* 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));
+ 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);
+ ir_node *val = workset_get_val(ws, i);
+ unsigned dist = get_distance(instr, instr_nr, val, !is_usage);
workset_set_time(ws, i, dist);
}
We don't do this for phis though
*/
for (i = max_allowed; i < ws->len; ++i) {
- ir_node *irn = ws->vals[i].irn;
+ ir_node *node = ws->vals[i].node;
- DBG((dbg, DBG_DECIDE, " disposing node %+F (%u)\n", irn,
+ DBG((dbg, DBG_DECIDE, " disposing node %+F (%u)\n", node,
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);
+ && !ws->vals[i].reloaded) {
+ //be_add_spill(senv, node, instr);
}
- if (is_Phi(irn))
+ if (is_Phi(node))
continue;
- if (! pset_find_ptr(env->used, irn)) {
- ir_node *curr_bb = get_nodes_block(env->instr);
- workset_t *ws_start = get_block_info(curr_bb)->ws_start;
- workset_remove(ws_start, irn);
+ if (! ir_nodeset_contains(&used, node)) {
+ ir_node *curr_bb = get_nodes_block(instr);
+ workset_t *ws_start = get_block_info(curr_bb)->start_workset;
+ workset_remove(ws_start, node);
- DBG((dbg, DBG_DECIDE, " (and removing %+F from start workset)\n", irn));
+ DBG((dbg, DBG_DECIDE, " (and removing %+F from start workset)\n", node));
}
}
/*
3. Insert the new values into the workset
*/
- for (i = 0; i < demand; ++i) {
- workset_insert(env, env->ws, to_insert[i], 1);
- }
+ for (i = 0; i < demand; ++i)
+ workset_insert(ws, to_insert[i], 1);
}
-static void belady(ir_node *block, void *env);
-
-/**
- * Decides whether a specific node should be in the start workset or not
+/** Decides whether a specific node should be in the start workset or not
*
* @param env belady environment
* @param first
* @param node the node to test
- * @param block the block of the node
* @param loop the loop of the node
*/
-static loc_t to_take_or_not_to_take(belady_env_t *env, ir_node* first,
- ir_node *node, ir_node *block,
- ir_loop *loop)
+static loc_t to_take_or_not_to_take(ir_node* first, ir_node *node,
+ ir_loop *loop)
{
be_next_use_t next_use;
- loc_t loc;
- loc.time = USES_INFINITY;
- loc.irn = node;
- loc.reloaded_value = 0;
- (void) block;
+ loc_t loc;
+
+ loc.time = USES_INFINITY;
+ loc.node = node;
+ //loc.reloaded = rand() % 2; /* provoke a bug... */
+ loc.reloaded = 0;
- if (!arch_irn_consider_in_reg_alloc(env->arch, env->cls, node)) {
+ if (!arch_irn_consider_in_reg_alloc(arch_env, cls, node)) {
loc.time = USES_INFINITY;
return loc;
}
/* We have to keep nonspillable nodes in the workingset */
- if(arch_irn_get_flags(env->arch, node) & arch_irn_flags_dont_spill) {
+ if(arch_irn_get_flags(arch_env, node) & arch_irn_flags_dont_spill) {
loc.time = 0;
DBG((dbg, DBG_START, " %+F taken (dontspill node)\n", node, loc.time));
return loc;
}
- next_use = be_get_next_use(env->uses, first, 0, node, 0);
+ next_use = be_get_next_use(uses, first, 0, node, 0);
if(USES_IS_INFINITE(next_use.time)) {
// the nodes marked as live in shouldn't be dead, so it must be a phi
assert(is_Phi(node));
loc.time = USES_INFINITY;
DBG((dbg, DBG_START, " %+F not taken (dead)\n", node));
if(is_Phi(node)) {
- be_spill_phi(env->senv, node);
+ be_spill_phi(senv, node);
}
return loc;
}
return loc;
}
-/*
- * Computes set of live-ins for each block with multiple predecessors
- * and notifies spill algorithm which phis need to be spilled
+/**
+ * Computes the start-workset for a block with multiple predecessors. We assume
+ * that at least 1 of the predeccesors is a back-edge which means we're at the
+ * beginning of a loop. We try to reload as much values as possible now so they
+ * don't get reloaded inside the loop.
*/
-static void compute_live_ins(ir_node *block, void *data) {
- belady_env_t *env = data;
- ir_loop *loop = get_irn_loop(block);
- const be_lv_t *lv = env->lv;
- block_info_t *block_info;
- ir_node *first, *irn;
- loc_t loc, *starters, *delayed;
- int i, len, ws_count;
- int free_slots, free_pressure_slots;
- unsigned pressure;
-
- if (get_Block_n_cfgpreds(block) == 1 && get_irg_start_block(get_irn_irg(block)) != block)
- return;
-
- block_info = new_block_info(&env->ob);
- set_block_info(block, block_info);
+static void compute_live_ins(const ir_node *block)
+{
+ ir_loop *loop = get_irn_loop(block);
+ ir_node *first;
+ ir_node *node;
+ loc_t loc;
+ loc_t *starters;
+ loc_t *delayed;
+ int i, len, ws_count;
+ int free_slots, free_pressure_slots;
+ unsigned pressure;
+ //int arity;
+ //int n_pred_worksets;
+ //workset_t **pred_worksets;
/* Collect all values living at start of block */
starters = NEW_ARR_F(loc_t, 0);
first = sched_first(block);
/* check all Phis first */
- sched_foreach(block, irn) {
- if (! is_Phi(irn))
+ sched_foreach(block, node) {
+ if (! is_Phi(node))
break;
- loc = to_take_or_not_to_take(env, first, irn, block, loop);
- /* the phis can't be reloaded here (they just get defined) */
- loc.reloaded_value = 0;
+ loc = to_take_or_not_to_take(first, node, loop);
if (! USES_IS_INFINITE(loc.time)) {
if (USES_IS_PENDING(loc.time))
be_lv_foreach(lv, block, be_lv_state_in, i) {
ir_node *node = be_lv_get_irn(lv, block, i);
- loc = to_take_or_not_to_take(env, first, node, block, loop);
+ loc = to_take_or_not_to_take(first, node, loop);
if (! USES_IS_INFINITE(loc.time)) {
if (USES_IS_PENDING(loc.time))
}
}
- pressure = be_get_loop_pressure(env->loop_ana, env->cls, loop);
+ pressure = be_get_loop_pressure(loop_ana, cls, loop);
assert(ARR_LEN(delayed) <= (signed)pressure);
- free_slots = env->n_regs - ARR_LEN(starters);
- free_pressure_slots = env->n_regs - (pressure - ARR_LEN(delayed));
+ free_slots = n_regs - ARR_LEN(starters);
+ free_pressure_slots = n_regs - (pressure - ARR_LEN(delayed));
free_slots = MIN(free_slots, free_pressure_slots);
- /* append nodes delayed due to loop structure until start set is full */
- for (i = 0; i < ARR_LEN(delayed) && i < free_slots; ++i) {
- DBG((dbg, DBG_START, " delayed %+F taken\n", delayed[i].irn));
- ARR_APP1(loc_t, starters, delayed[i]);
- delayed[i].irn = NULL;
- }
- /* spill all delayed phis which didn't make it into start workset */
- for ( ; i < ARR_LEN(delayed); ++i) {
- ir_node *irn = delayed[i].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);
+ /* so far we only put nodes into the starters list that are used inside
+ * the loop. If register pressure in the loop is low then we can take some
+ * values and let them live through the loop */
+ if(free_slots > 0) {
+ qsort(delayed, ARR_LEN(delayed), sizeof(delayed[0]), loc_compare);
+
+ for (i = 0; i < ARR_LEN(delayed) && i < free_slots; ++i) {
+ DBG((dbg, DBG_START, " delayed %+F taken\n", delayed[i].node));
+ ARR_APP1(loc_t, starters, delayed[i]);
+ delayed[i].node = NULL;
}
}
+
+ /* spill phis (the actual phis not just their values) that are in this block
+ * but not in the start workset */
+ for (i = ARR_LEN(delayed) - 1; i >= 0; --i) {
+ ir_node *node = delayed[i].node;
+ if(node == NULL || !is_Phi(node) || get_nodes_block(node) != block)
+ continue;
+
+ DBG((dbg, DBG_START, " spilling delayed phi %+F\n", node));
+ be_spill_phi(senv, node);
+ }
DEL_ARR_F(delayed);
/* Sort start values by first use */
qsort(starters, ARR_LEN(starters), sizeof(starters[0]), loc_compare);
/* Copy the best ones from starters to start workset */
- ws_count = MIN(ARR_LEN(starters), env->n_regs);
- block_info->ws_start = new_workset(env, &env->ob);
- workset_bulk_fill(block_info->ws_start, ws_count, starters);
+ ws_count = MIN(ARR_LEN(starters), n_regs);
+ workset_clear(ws);
+ workset_bulk_fill(ws, ws_count, starters);
- /* The phis of this block which are not in the start set have to be spilled later. */
+ /* spill phis (the actual phis not just their values) that are in this block
+ * but not in the start workset */
len = ARR_LEN(starters);
for (i = ws_count; i < len; ++i) {
- irn = starters[i].irn;
- if (! is_Phi(irn) || get_nodes_block(irn) != block)
+ ir_node *node = starters[i].node;
+ if (! is_Phi(node) || get_nodes_block(node) != block)
continue;
- be_spill_phi(env->senv, irn);
+ DBG((dbg, DBG_START, " spilling phi %+F\n", node));
+ be_spill_phi(senv, node);
}
DEL_ARR_F(starters);
-}
-/**
- * Collects all values live-in at block @p block and all phi results in this block.
- * Then it adds the best values (at most n_regs) to the blocks start_workset.
- * The phis among the remaining values get spilled: Introduce psudo-copies of
- * their args to break interference and make it possible to spill them to the
- * same spill slot.
- */
-static block_info_t *compute_block_start_info(belady_env_t *env, ir_node *block) {
- ir_node *pred_block;
- block_info_t *res, *pred_info;
-
- /* Have we seen this block before? */
- res = get_block_info(block);
- if (res)
- return res;
-
- /* Create the block info for this block. */
- res = new_block_info(&env->ob);
- set_block_info(block, res);
-
- /* Use endset of predecessor block as startset */
- assert(get_Block_n_cfgpreds(block) == 1 && block != get_irg_start_block(get_irn_irg(block)));
- pred_block = get_Block_cfgpred_block(block, 0);
- pred_info = get_block_info(pred_block);
-
- /* if pred block has not been processed yet, do it now */
- if (pred_info == NULL || pred_info->processed == 0) {
- belady(pred_block, env);
- pred_info = get_block_info(pred_block);
+#if 0
+ /* determine reloaded status of the values: If there's 1 pred block (which
+ * is no backedge) where the value is reloaded then we must set it to
+ * reloaded here. We place spills in all pred where the value was not yet
+ * reloaded to be sure we have a spill on each path */
+ n_pred_worksets = 0;
+ arity = get_irn_arity(block);
+ pred_worksets = alloca(sizeof(pred_worksets[0]) * arity);
+ for(i = 0; i < arity; ++i) {
+ ir_node *pred_block = get_Block_cfgpred_block(block, i);
+ block_info_t *pred_info = get_block_info(pred_block);
+ if(pred_info == NULL)
+ continue;
+
+ pred_worksets[n_pred_worksets] = pred_info->end_workset;
+ ++n_pred_worksets;
}
- /* now we have an end_set of pred */
- assert(pred_info->ws_end && "The recursive call (above) is supposed to compute an end_set");
- res->ws_start = workset_clone(env, &env->ob, pred_info->ws_end);
+ for(i = 0; i < ws_count; ++i) {
+ loc_t *loc = &ws->vals[i];
+ ir_node *value = loc->node;
+ int reloaded;
+ int n;
- return res;
-}
+ /* phis from this block aren't reloaded */
+ if(get_nodes_block(value) == block) {
+ assert(is_Phi(value));
+ loc->reloaded = value_not_reloaded;
+ continue;
+ }
+ /* was the value reloaded on any of the other inputs */
+ reloaded = 0;
+ arity = get_Block_n_cfgpreds(block);
+ for(n = 0; n < n_pred_worksets; ++n) {
+ workset_t *pred_workset = pred_worksets[n];
+ int p_len = workset_get_length(pred_workset);
+ int p;
+
+ for(p = 0; p < p_len; ++p) {
+ loc_t *l = &pred_workset->vals[p];
+ if(l->node == value) {
+ if(l->reloaded) {
+ reloaded = 1;
+ }
+ break;
+ }
+ }
+ if(p >= p_len) {
+ reloaded = 1;
+ break;
+ }
+ }
+ }
+#endif
+}
/**
* For the given block @p block, decide for each values
* whether it is used from a register or is reloaded
* before the use.
*/
-static void belady(ir_node *block, void *data) {
- belady_env_t *env = data;
- workset_t *new_vals;
- ir_node *irn;
- int iter;
- block_info_t *block_info;
-
- /* make sure we have blockinfo (with startset) */
- block_info = get_block_info(block);
- if (block_info == NULL)
- block_info = compute_block_start_info(env, block);
-
- /* Don't do a block twice */
- if(block_info->processed)
+static void belady(ir_node *block)
+{
+ workset_t *new_vals;
+ ir_node *irn;
+ int iter;
+ block_info_t *block_info;
+ int i, arity;
+ int has_backedges = 0;
+ //int first = 0;
+ const ir_edge_t *edge;
+
+ /* no need to process a block twice */
+ if(get_block_info(block) != NULL) {
return;
+ }
+
+ /* check if all predecessor blocks are processed yet (though for backedges
+ * we have to make an exception as we can't process them first) */
+ arity = get_Block_n_cfgpreds(block);
+ for(i = 0; i < arity; ++i) {
+ ir_node *pred_block = get_Block_cfgpred_block(block, i);
+ block_info_t *pred_info = get_block_info(pred_block);
+
+ if(pred_info == NULL) {
+ /* process predecessor first (it will be in the queue already) */
+ if(!is_backedge(block, i)) {
+ return;
+ }
+ has_backedges = 1;
+ }
+ }
+ (void) has_backedges;
+ if(arity == 0) {
+ workset_clear(ws);
+ } else if(arity == 1) {
+ ir_node *pred_block = get_Block_cfgpred_block(block, 0);
+ block_info_t *pred_info = get_block_info(pred_block);
+
+ assert(pred_info != NULL);
+ workset_copy(ws, pred_info->end_workset);
+ } else {
+ /* we need 2 heuristics here, for the case when all predecessor blocks
+ * are known and when some are backedges (and therefore can't be known
+ * yet) */
+ compute_live_ins(block);
+ }
- /* get the starting workset for this block */
DBG((dbg, DBG_DECIDE, "\n"));
DBG((dbg, DBG_DECIDE, "Decide for %+F\n", block));
- workset_copy(env, env->ws, block_info->ws_start);
+ block_info = new_block_info();
+ set_block_info(block, block_info);
+
DBG((dbg, DBG_WSETS, "Start workset for %+F:\n", block));
- workset_foreach(env->ws, irn, iter)
- DBG((dbg, DBG_WSETS, " %+F (%u)\n", irn, workset_get_time(env->ws, iter)));
+ workset_foreach(ws, irn, iter) {
+ DBG((dbg, DBG_WSETS, " %+F (%u)\n", irn,
+ workset_get_time(ws, iter)));
+ }
+
+ block_info->start_workset = workset_clone(ws);
/* process the block from start to end */
DBG((dbg, DBG_WSETS, "Processing...\n"));
- env->used = pset_new_ptr_default();
- env->instr_nr = 0;
- new_vals = new_workset(env, &env->ob);
+ ir_nodeset_init(&used);
+ instr_nr = 0;
+ /* TODO: this leaks (into the obstack)... */
+ new_vals = new_workset();
+
sched_foreach(block, irn) {
int i, arity;
- assert(workset_get_length(env->ws) <= env->n_regs && "Too much values in workset!");
+ assert(workset_get_length(ws) <= n_regs);
- /* projs are handled with the tuple value.
- * Phis are no real instr (see insert_starters())
- * instr_nr does not increase */
- if (is_Proj(irn) || is_Phi(irn)) {
- DBG((dbg, DBG_DECIDE, " ...%+F skipped\n", irn));
+ /* Phis are no real instr (see insert_starters()) */
+ if (is_Phi(irn)) {
continue;
}
DBG((dbg, DBG_DECIDE, " ...%+F\n", irn));
/* set instruction in the workset */
- env->instr = irn;
+ instr = irn;
/* allocate all values _used_ by this instruction */
workset_clear(new_vals);
for(i = 0, arity = get_irn_arity(irn); i < arity; ++i) {
- /* (note that reloaded_value is not interesting here) */
- workset_insert(env, new_vals, get_irn_n(irn, i), 0);
+ ir_node *in = get_irn_n(irn, i);
+ if (!arch_irn_consider_in_reg_alloc(arch_env, cls, in))
+ continue;
+
+ /* (note that reloaded_value is irrelevant here) */
+ workset_insert(new_vals, in, 0);
}
- displace(env, new_vals, 1);
+ displace(new_vals, 1);
/* allocate all values _defined_ by this instruction */
workset_clear(new_vals);
- if (get_irn_mode(irn) == mode_T) { /* special handling for tuples and projs */
+ if (get_irn_mode(irn) == mode_T) {
const ir_edge_t *edge;
foreach_out_edge(irn, edge) {
ir_node *proj = get_edge_src_irn(edge);
- workset_insert(env, new_vals, proj, 0);
+ if (!arch_irn_consider_in_reg_alloc(arch_env, cls, proj))
+ continue;
+ workset_insert(new_vals, proj, 0);
}
} else {
- workset_insert(env, new_vals, irn, 0);
+ if (!arch_irn_consider_in_reg_alloc(arch_env, cls, irn))
+ continue;
+ workset_insert(new_vals, irn, 0);
}
- displace(env, new_vals, 0);
+ displace(new_vals, 0);
- env->instr_nr++;
+ instr_nr++;
}
- del_pset(env->used);
+ ir_nodeset_destroy(&used);
/* Remember end-workset for this block */
- block_info->ws_end = workset_clone(env, &env->ob, env->ws);
- block_info->processed = 1;
+ block_info->end_workset = workset_clone(ws);
DBG((dbg, DBG_WSETS, "End workset for %+F:\n", block));
- workset_foreach(block_info->ws_end, irn, iter)
- DBG((dbg, DBG_WSETS, " %+F (%u)\n", irn, workset_get_time(block_info->ws_end, iter)));
+ workset_foreach(ws, irn, iter)
+ DBG((dbg, DBG_WSETS, " %+F (%u)\n", irn,
+ workset_get_time(ws, iter)));
+
+ /* add successor blocks into worklist */
+ foreach_block_succ(block, edge) {
+ ir_node *succ = get_edge_src_irn(edge);
+ pdeq_putr(worklist, succ);
+ }
}
/**
*/
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;
+ (void) data;
DBG((dbg, DBG_FIX, "\n"));
DBG((dbg, DBG_FIX, "Fixing %+F\n", block));
- start_workset = get_block_info(block)->ws_start;
+ start_workset = get_block_info(block)->start_workset;
/* process all pred blocks */
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 *pred = get_Block_cfgpred_block(block, i);
+ workset_t *pred_end_workset = get_block_info(pred)->end_workset;
ir_node *node;
DBG((dbg, DBG_FIX, " Pred %+F\n", pred));
/* spill all values not used anymore */
- workset_foreach(workset_pred_end, node, iter) {
+ workset_foreach(pred_end_workset, node, iter) {
ir_node *n2;
int iter2;
int found = 0;
}
#if 0
- if(!found && be_is_live_out(env->lv, pred, node)
- && !workset_pred_end->vals[iter].reloaded_value) {
+ if(!found && be_is_live_out(lv, pred, node)
+ && !pred_end_workset->vals[iter].reloaded) {
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);
+ be_add_spill(senv, node, insert_point);
}
#endif
}
node = get_irn_n(node, i);
/* we might have unknowns as argument for the phi */
- if(!arch_irn_consider_in_reg_alloc(env->arch, env->cls, node))
+ if(!arch_irn_consider_in_reg_alloc(arch_env, cls, node))
continue;
}
/* check if node is in a register at end of pred */
- if(workset_contains(workset_pred_end, node))
+ if(workset_contains(pred_end_workset, node))
continue;
/* 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);
+ be_add_reload_on_edge(senv, node, block, i, cls, 1);
}
}
}
-/**
- * Do spilling for a register class on a graph using the belady heuristic.
- * In the transformed graph, the register pressure never exceeds the number
- * of available registers.
- *
- * @param birg The backend graph
- * @param cls The register class to spill
- */
-static void be_spill_belady(be_irg_t *birg, const arch_register_class_t *cls) {
- be_spill_belady_spill_env(birg, cls, NULL);
-}
-
-void be_spill_belady_spill_env(be_irg_t *birg, const arch_register_class_t *cls, spill_env_t *spill_env) {
- belady_env_t env;
+static void be_spill_belady(be_irg_t *birg, const arch_register_class_t *rcls)
+{
ir_graph *irg = be_get_birg_irg(birg);
- int n_regs;
- n_regs = cls->n_regs - be_put_ignore_regs(birg, cls, NULL);
be_liveness_assure_sets(be_assure_liveness(birg));
/* construct control flow loop tree */
be_clear_links(irg);
/* init belady env */
- obstack_init(&env.ob);
- env.arch = birg->main_env->arch_env;
- env.cls = cls;
- env.lv = be_get_birg_liveness(birg);
- env.n_regs = n_regs;
- env.ws = new_workset(&env, &env.ob);
- env.uses = be_begin_uses(irg, env.lv);
- env.loop_ana = be_new_loop_pressure(birg);
- if(spill_env == NULL) {
- env.senv = be_new_spill_env(birg);
- } else {
- env.senv = spill_env;
+ obstack_init(&obst);
+ arch_env = birg->main_env->arch_env;
+ cls = rcls;
+ lv = be_get_birg_liveness(birg);
+ n_regs = cls->n_regs - be_put_ignore_regs(birg, cls, NULL);
+ ws = new_workset();
+ uses = be_begin_uses(irg, lv);
+ loop_ana = be_new_loop_pressure(birg);
+ senv = be_new_spill_env(birg);
+ worklist = new_pdeq();
+
+ pdeq_putr(worklist, get_irg_start_block(irg));
+
+ while(!pdeq_empty(worklist)) {
+ ir_node *block = pdeq_getl(worklist);
+ belady(block);
}
+ /* end block might not be reachable in endless loops */
+ belady(get_irg_end_block(irg));
- /* Decide which phi nodes will be spilled and place copies for them into the graph */
- irg_block_walk_graph(irg, compute_live_ins, NULL, &env);
- /* Fix high register pressure with belady algorithm */
- 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);
+ del_pdeq(worklist);
- be_end_uses(env.uses);
- be_free_loop_pressure(env.loop_ana);
- obstack_free(&env.ob, NULL);
+ /* belady was block-local, fix the global flow by adding reloads on the
+ * edges */
+ irg_block_walk_graph(irg, fix_block_borders, NULL, NULL);
/* Insert spill/reload nodes into the graph and fix usages */
- be_insert_spills_reloads(env.senv);
+ be_insert_spills_reloads(senv);
/* clean up */
- if(spill_env == NULL)
- be_delete_spill_env(env.senv);
+ be_delete_spill_env(senv);
+ be_end_uses(uses);
+ be_free_loop_pressure(loop_ana);
+ obstack_free(&obst, NULL);
}
void be_init_spillbelady(void)
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