cleanup backend: make pre_spill_prepare_constraint independent of chordal allocator...
[libfirm] / ir / opt / ldstopt.c
index 2ef7cec..ea3b1f1 100644 (file)
@@ -23,9 +23,7 @@
  * @author  Michael Beck
  * @version $Id$
  */
-#ifdef HAVE_CONFIG_H
-# include "config.h"
-#endif
+#include "config.h"
 
 #include <string.h>
 
@@ -48,9 +46,9 @@
 #include "irtools.h"
 #include "opt_polymorphy.h"
 #include "irmemory.h"
-#include "xmalloc.h"
 #include "irphase_t.h"
 #include "irgopt.h"
+#include "set.h"
 #include "debug.h"
 
 /** The debug handle. */
@@ -707,7 +705,7 @@ static void handle_load_update(ir_node *load) {
                /* a Load whose value is neither used nor exception checked, remove it */
                exchange(info->projs[pn_Load_M], mem);
                if (info->projs[pn_Load_X_regular])
-                       exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load)));
+                       exchange(info->projs[pn_Load_X_regular], new_r_Jmp(get_nodes_block(load)));
                kill_node(load);
                reduce_adr_usage(ptr);
        }
@@ -856,29 +854,31 @@ static int try_load_after_store(ir_node *load,
        store_mode     = get_irn_mode(get_Store_value(store));
        store_mode_len = get_mode_size_bytes(store_mode);
        delta          = load_offset - store_offset;
-       if (delta < 0 || delta + load_mode_len > store_mode_len)
-               return 0;
+       store_value    = get_Store_value(store);
 
-       if (get_mode_arithmetic(store_mode) != irma_twos_complement ||
-           get_mode_arithmetic(load_mode)  != irma_twos_complement)
-               return 0;
+       if (delta != 0 || store_mode != load_mode) {
+               if (delta < 0 || delta + load_mode_len > store_mode_len)
+                       return 0;
 
-       store_value = get_Store_value(store);
+               if (get_mode_arithmetic(store_mode) != irma_twos_complement ||
+                       get_mode_arithmetic(load_mode)  != irma_twos_complement)
+                       return 0;
 
-       /* produce a shift to adjust offset delta */
-       if (delta > 0) {
-               ir_node *cnst;
 
-               /* FIXME: only true for little endian */
-               cnst        = new_Const_long(mode_Iu, delta * 8);
-               store_value = new_r_Shr(current_ir_graph, get_nodes_block(load),
-                                       store_value, cnst, store_mode);
-       }
+               /* produce a shift to adjust offset delta */
+               if (delta > 0) {
+                       ir_node *cnst;
+
+                       /* FIXME: only true for little endian */
+                       cnst        = new_Const_long(mode_Iu, delta * 8);
+                       store_value = new_r_Shr(get_nodes_block(load),
+                                                                       store_value, cnst, store_mode);
+               }
 
-       /* add an convert if needed */
-       if (store_mode != load_mode) {
-               store_value = new_r_Conv(current_ir_graph, get_nodes_block(load),
-                                        store_value, load_mode);
+               /* add an convert if needed */
+               if (store_mode != load_mode) {
+                       store_value = new_r_Conv(get_nodes_block(load), store_value, load_mode);
+               }
        }
 
        DBG_OPT_RAW(load, store_value);
@@ -894,7 +894,7 @@ static int try_load_after_store(ir_node *load,
                res |= CF_CHANGED;
        }
        if (info->projs[pn_Load_X_regular]) {
-               exchange( info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load)));
+               exchange( info->projs[pn_Load_X_regular], new_r_Jmp(get_nodes_block(load)));
                res |= CF_CHANGED;
        }
 
@@ -971,13 +971,13 @@ static unsigned follow_Mem_chain(ir_node *load, ir_node *curr) {
                                if (info->projs[pn_Load_res]) {
                                        if (pred_info->projs[pn_Load_res] == NULL) {
                                                /* create a new Proj again */
-                                               pred_info->projs[pn_Load_res] = new_r_Proj(current_ir_graph, get_nodes_block(pred), pred, get_Load_mode(pred), pn_Load_res);
+                                               pred_info->projs[pn_Load_res] = new_r_Proj(get_nodes_block(pred), pred, get_Load_mode(pred), pn_Load_res);
                                        }
                                        value = pred_info->projs[pn_Load_res];
 
                                        /* add an convert if needed */
                                        if (get_Load_mode(pred) != load_mode) {
-                                               value = new_r_Conv(current_ir_graph, get_nodes_block(load), value, load_mode);
+                                               value = new_r_Conv(get_nodes_block(load), value, load_mode);
                                        }
 
                                        exchange(info->projs[pn_Load_res], value);
@@ -992,7 +992,7 @@ static unsigned follow_Mem_chain(ir_node *load, ir_node *curr) {
                                        res |= CF_CHANGED;
                                }
                                if (info->projs[pn_Load_X_regular]) {
-                                       exchange( info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load)));
+                                       exchange( info->projs[pn_Load_X_regular], new_r_Jmp(get_nodes_block(load)));
                                        res |= CF_CHANGED;
                                }
 
@@ -1067,7 +1067,7 @@ ir_node *can_replace_load_by_const(const ir_node *load, ir_node *c) {
 
                        /* copy the value from the const code irg and cast it */
                        res = copy_const_value(dbg, c);
-                       res = new_rd_Conv(dbg, current_ir_graph, block, res, l_mode);
+                       res = new_rd_Conv(dbg, block, res, l_mode);
                }
        } else {
                /* copy the value from the const code irg */
@@ -1118,7 +1118,7 @@ static unsigned optimize_load(ir_node *load)
                         */
                        exchange(info->projs[pn_Load_X_except], new_Bad());
                        info->projs[pn_Load_X_except] = NULL;
-                       exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load)));
+                       exchange(info->projs[pn_Load_X_regular], new_r_Jmp(get_nodes_block(load)));
                        info->projs[pn_Load_X_regular] = NULL;
                        res |= CF_CHANGED;
                }
@@ -1133,7 +1133,7 @@ static unsigned optimize_load(ir_node *load)
 
                if (info->projs[pn_Load_X_regular]) {
                        /* should not happen, but if it does, remove it */
-                       exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load)));
+                       exchange(info->projs[pn_Load_X_regular], new_r_Jmp(get_nodes_block(load)));
                        res |= CF_CHANGED;
                }
                kill_node(load);
@@ -1161,7 +1161,7 @@ static unsigned optimize_load(ir_node *load)
                                res |= CF_CHANGED;
                        }
                        if (info->projs[pn_Load_X_regular]) {
-                               exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load)));
+                               exchange(info->projs[pn_Load_X_regular], new_r_Jmp(get_nodes_block(load)));
                                info->projs[pn_Load_X_regular] = NULL;
                                res |= CF_CHANGED;
                        }
@@ -1201,7 +1201,7 @@ static unsigned optimize_load(ir_node *load)
                        res |= CF_CHANGED;
                }
                if (info->projs[pn_Load_X_regular]) {
-                       exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load)));
+                       exchange(info->projs[pn_Load_X_regular], new_r_Jmp(get_nodes_block(load)));
                        info->projs[pn_Load_X_regular] = NULL;
                        res |= CF_CHANGED;
                }
@@ -1442,6 +1442,7 @@ static unsigned optimize_store(ir_node *store) {
        if (entity != NULL && !(get_entity_usage(entity) & ir_usage_read)) {
                ldst_info_t *info = get_irn_link(store);
                if (info->projs[pn_Store_X_except] == NULL) {
+                       DB((dbg, LEVEL_1, "  Killing useless %+F to never read entity %+F\n", store, entity));
                        exchange(info->projs[pn_Store_M], get_Store_mem(store));
                        kill_node(store);
                        reduce_adr_usage(ptr);
@@ -1610,10 +1611,10 @@ static unsigned optimize_phi(ir_node *phi, walk_env_t *wenv)
        block = get_nodes_block(phi);
 
        /* second step: create a new memory Phi */
-       phiM = new_rd_Phi(get_irn_dbg_info(phi), current_ir_graph, block, n, inM, mode_M);
+       phiM = new_rd_Phi(get_irn_dbg_info(phi), block, n, inM, mode_M);
 
        /* third step: create a new data Phi */
-       phiD = new_rd_Phi(get_irn_dbg_info(phi), current_ir_graph, block, n, inD, mode);
+       phiD = new_rd_Phi(get_irn_dbg_info(phi), block, n, inD, mode);
 
        /* rewire memory and kill the node */
        for (i = n - 1; i >= 0; --i) {
@@ -1627,19 +1628,19 @@ static unsigned optimize_phi(ir_node *phi, walk_env_t *wenv)
        }
 
        /* fourth step: create the Store */
-       store = new_rd_Store(db, current_ir_graph, block, phiM, ptr, phiD);
+       store = new_rd_Store(db, block, phiM, ptr, phiD, 0);
 #ifdef DO_CACHEOPT
        co_set_irn_name(store, co_get_irn_ident(old_store));
 #endif
 
-       projM = new_rd_Proj(NULL, current_ir_graph, block, store, mode_M, pn_Store_M);
+       projM = new_rd_Proj(NULL, block, store, mode_M, pn_Store_M);
 
        info = get_ldst_info(store, &wenv->obst);
        info->projs[pn_Store_M] = projM;
 
        /* fifths step: repair exception flow */
        if (exc) {
-               ir_node *projX = new_rd_Proj(NULL, current_ir_graph, block, store, mode_X, pn_Store_X_except);
+               ir_node *projX = new_rd_Proj(NULL, block, store, mode_X, pn_Store_X_except);
 
                info->projs[pn_Store_X_except] = projX;
                info->exc_block                = exc;
@@ -1696,7 +1697,6 @@ typedef struct scc {
 typedef struct node_entry {
        unsigned DFSnum;    /**< the DFS number of this node */
        unsigned low;       /**< the low number of this node */
-       ir_node  *header;   /**< the header of this node */
        int      in_stack;  /**< flag, set if the node is on the stack */
        ir_node  *next;     /**< link to the next node the the same scc */
        scc      *pscc;     /**< the scc of this node */
@@ -1783,6 +1783,33 @@ struct phi_entry {
        phi_entry *next;
 };
 
+/**
+ * An entry in the avail set.
+ */
+typedef struct avail_entry_t {
+       ir_node *ptr;   /**< the address pointer */
+       ir_mode *mode;  /**< the load mode */
+       ir_node *load;  /**< the associated Load */
+} avail_entry_t;
+
+/**
+ * Compare two avail entries.
+ */
+static int cmp_avail_entry(const void *elt, const void *key, size_t size) {
+       const avail_entry_t *a = elt;
+       const avail_entry_t *b = key;
+       (void) size;
+
+       return a->ptr != b->ptr || a->mode != b->mode;
+}  /* cmp_avail_entry */
+
+/**
+ * Calculate the hash value of an avail entry.
+ */
+static unsigned hash_cache_entry(const avail_entry_t *entry) {
+       return get_irn_idx(entry->ptr) * 9 + HASH_PTR(entry->mode);
+}  /* hash_cache_entry */
+
 /**
  * Move loops out of loops if possible.
  *
@@ -1794,6 +1821,9 @@ static void move_loads_out_of_loops(scc *pscc, loop_env *env) {
        ir_entity *ent;
        int       j;
        phi_entry *phi_list = NULL;
+       set       *avail;
+
+       avail = new_set(cmp_avail_entry, 8);
 
        /* collect all outer memories */
        for (phi = pscc->head; phi != NULL; phi = next) {
@@ -1804,7 +1834,7 @@ static void move_loads_out_of_loops(scc *pscc, loop_env *env) {
                if (! is_Phi(phi))
                        continue;
 
-               assert(get_irn_mode(phi) == mode_M && "DFS geturn non-memory Phi");
+               assert(get_irn_mode(phi) == mode_M && "DFS return non-memory Phi");
 
                for (j = get_irn_arity(phi) - 1; j >= 0; --j) {
                        ir_node    *pred = get_irn_n(phi, j);
@@ -1824,6 +1854,10 @@ static void move_loads_out_of_loops(scc *pscc, loop_env *env) {
        /* no Phis no fun */
        assert(phi_list != NULL && "DFS found a loop without Phi");
 
+       /* for now, we cannot handle more than one input (only reducible cf) */
+       if (phi_list->next != NULL)
+               return;
+
        for (load = pscc->head; load; load = next) {
                ir_mode *load_mode;
                node_entry *ne = get_irn_ne(load, env);
@@ -1837,10 +1871,10 @@ static void move_loads_out_of_loops(scc *pscc, loop_env *env) {
                        if (info->projs[pn_Load_res] == NULL || info->projs[pn_Load_X_regular] != NULL || info->projs[pn_Load_X_except] != NULL)
                                continue;
 
-                       /* for now, we can only handle Load(Global) */
+                       /* for now, we can only move Load(Global) */
                        if (! is_Global(ptr))
                                continue;
-                       ent = get_Global_entity(ptr);
+                       ent       = get_Global_entity(ptr);
                        load_mode = get_Load_mode(load);
                        for (other = pscc->head; other != NULL; other = next_other) {
                                node_entry *ne = get_irn_ne(other, env);
@@ -1856,17 +1890,13 @@ static void move_loads_out_of_loops(scc *pscc, loop_env *env) {
                                        if (rel != ir_no_alias)
                                                break;
                                }
-                               /* only pure Calls are allowed here, so ignore them */
+                               /* only Phis and pure Calls are allowed here, so ignore them */
                        }
                        if (other == NULL) {
                                ldst_info_t *ninfo;
                                phi_entry   *pe;
                                dbg_info    *db;
 
-                               /* for now, we cannot handle more than one input */
-                               if (phi_list->next != NULL)
-                                       return;
-
                                /* yep, no aliasing Store found, Load can be moved */
                                DB((dbg, LEVEL_1, "  Found a Load that could be moved: %+F\n", load));
 
@@ -1877,16 +1907,26 @@ static void move_loads_out_of_loops(scc *pscc, loop_env *env) {
                                        ir_node *blk  = get_nodes_block(phi);
                                        ir_node *pred = get_Block_cfgpred_block(blk, pos);
                                        ir_node *irn, *mem;
-
-                                       pe->load = irn = new_rd_Load(db, current_ir_graph, pred, get_Phi_pred(phi, pos), ptr, load_mode);
+                                       avail_entry_t entry, *res;
+
+                                       entry.ptr  = ptr;
+                                       entry.mode = load_mode;
+                                       res = set_find(avail, &entry, sizeof(entry), hash_cache_entry(&entry));
+                                       if (res != NULL) {
+                                               irn = res->load;
+                                       } else {
+                                               irn = new_rd_Load(db, pred, get_Phi_pred(phi, pos), ptr, load_mode, 0);
+                                               entry.load = irn;
+                                               set_insert(avail, &entry, sizeof(entry), hash_cache_entry(&entry));
+                                               DB((dbg, LEVEL_1, "  Created %+F in %+F\n", irn, pred));
+                                       }
+                                       pe->load = irn;
                                        ninfo = get_ldst_info(irn, phase_obst(&env->ph));
 
-                                       ninfo->projs[pn_Load_M] = mem = new_r_Proj(current_ir_graph, pred, irn, mode_M, pn_Load_M);
+                                       ninfo->projs[pn_Load_M] = mem = new_r_Proj(pred, irn, mode_M, pn_Load_M);
                                        set_Phi_pred(phi, pos, mem);
 
-                                       ninfo->projs[pn_Load_res] = new_r_Proj(current_ir_graph, pred, irn, load_mode, pn_Load_res);
-
-                                       DB((dbg, LEVEL_1, "  Created %+F in %+F\n", irn, pred));
+                                       ninfo->projs[pn_Load_res] = new_r_Proj(pred, irn, load_mode, pn_Load_res);
                                }
 
                                /* now kill the old Load */
@@ -1897,6 +1937,7 @@ static void move_loads_out_of_loops(scc *pscc, loop_env *env) {
                        }
                }
        }
+       del_set(avail);
 }  /* move_loads_out_of_loops */
 
 /**
@@ -1919,13 +1960,12 @@ static void process_loop(scc *pscc, loop_env *env) {
                next = e->next;
                b = get_irn_ne(block, env);
 
-               if (header) {
+               if (header != NULL) {
                        if (h->POnum < b->POnum) {
                                header = block;
                                h      = b;
                        }
-               }
-               else {
+               } else {
                        header = block;
                        h      = b;
                }
@@ -1980,10 +2020,12 @@ static void process_loop(scc *pscc, loop_env *env) {
                                                /* not a memory loop */
                                                goto fail;
                                        }
-                                       if (! out_rc) {
+                                       if (out_rc == NULL) {
+                                               /* first region constant */
                                                out_rc = pred;
                                                ++num_outside;
                                        } else if (out_rc != pred) {
+                                               /* another region constant */
                                                ++num_outside;
                                        }
                                }
@@ -2003,22 +2045,20 @@ static void process_loop(scc *pscc, loop_env *env) {
                for (irn = pscc->head; irn; irn = next) {
                        node_entry *e = get_irn_ne(irn, env);
                        next = e->next;
-                       e->header = NULL;
                        exchange(irn, out_rc);
                }
                env->changes |= DF_CHANGED;
                return;
        }
 
-       /* set the header for every node in this scc */
+#ifdef DEBUG_libfirm
        for (irn = pscc->head; irn; irn = next) {
                node_entry *e = get_irn_ne(irn, env);
-               e->header = header;
                next = e->next;
                DB((dbg, LEVEL_2, " %+F,", irn));
        }
        DB((dbg, LEVEL_2, "\n"));
-
+#endif
        move_loads_out_of_loops(pscc, env);
 
 fail:
@@ -2081,7 +2121,7 @@ static void dfs(ir_node *irn, loop_env *env)
                        ir_node *pred = get_irn_n(irn, i);
                        node_entry *o = get_irn_ne(pred, env);
 
-                       if (irn_not_visited(pred)) {
+                       if (!irn_visited(pred)) {
                                dfs(pred, env);
                                node->low = MIN(node->low, o->low);
                        }
@@ -2092,7 +2132,7 @@ static void dfs(ir_node *irn, loop_env *env)
                ir_node *pred = get_fragile_op_mem(irn);
                node_entry *o = get_irn_ne(pred, env);
 
-               if (irn_not_visited(pred)) {
+               if (!irn_visited(pred)) {
                        dfs(pred, env);
                        node->low = MIN(node->low, o->low);
                }
@@ -2102,7 +2142,7 @@ static void dfs(ir_node *irn, loop_env *env)
                ir_node *pred = get_Proj_pred(irn);
                node_entry *o = get_irn_ne(pred, env);
 
-               if (irn_not_visited(pred)) {
+               if (!irn_visited(pred)) {
                        dfs(pred, env);
                        node->low = MIN(node->low, o->low);
                }
@@ -2168,7 +2208,7 @@ static void do_dfs(ir_graph *irg, loop_env *env) {
        for (i = get_End_n_keepalives(end) - 1; i >= 0; --i) {
                ir_node *ka = get_End_keepalive(end, i);
 
-               if (is_Phi(ka) && irn_not_visited(ka))
+               if (is_Phi(ka) && !irn_visited(ka))
                        dfs(ka, env);
        }
        current_ir_graph = rem;
@@ -2258,5 +2298,5 @@ int optimize_load_store(ir_graph *irg) {
                have Bad() predecessors. */
                set_irg_doms_inconsistent(irg);
        }
-       return (int) env.changes;
+       return env.changes != 0;
 }  /* optimize_load_store */