set *lftr_edges; /**< the set of lftr edges */
unsigned replaced; /**< number of replaced ops */
unsigned lftr_replaced; /**< number of applied linear function test replacements */
- unsigned flags; /**< additional flags */
+ unsigned osr_flags; /**< additional flags steering the transformation */
+ unsigned need_postpass; /**< set, if a post pass is needed to fix Add and Sub nodes */
/** Function called to process a SCC. */
void (*process_scc)(scc *pscc, struct iv_env *env);
} iv_env;
(void) size;
return l1->src != l2->src;
-}
+} /* LFTR_cmp */
/**
* Find a LFTR edge.
+ *
+ * @param src the source node of the transition
*/
static LFTR_edge *LFTR_find(ir_node *src, iv_env *env) {
LFTR_edge key;
key.src = src;
return set_find(env->lftr_edges, &key, sizeof(key), HASH_PTR(src));
-}
+} /* LFTR_find */
/**
* Add a LFTR edge.
+ *
+ * @param src the source node of the edge
+ * @param dst the destination node of the edge
+ * @param code the opcode of the transformed transition
+ * @param rc the region const used in the transition
+ * @param env the environment
*/
static void LFTR_add(ir_node *src, ir_node *dst, ir_opcode code, ir_node *rc, iv_env *env) {
LFTR_edge key;
*/
// assert(LFTR_find(src, env) == NULL);
set_insert(env->lftr_edges, &key, sizeof(key), HASH_PTR(src));
-}
+} /* LFTR_add */
/**
- * Gets the node_entry of a node
+ * Gets the node_entry of a node.
+ *
+ * @param irn the node
+ * @param env the environment
*/
static node_entry *get_irn_ne(ir_node *irn, iv_env *env) {
node_entry *e = get_irn_link(irn);
- if (! e) {
+ if (e == NULL) {
e = obstack_alloc(&env->obst, sizeof(*e));
memset(e, 0, sizeof(*e));
set_irn_link(irn, e);
}
return e;
-}
+} /* get_irn_ne */
/**
- * Gets the scc from an IV.
+ * Gets the scc from an induction variable.
+ *
+ * @param iv any node of the induction variable
+ * @param env the environment
*/
static scc *get_iv_scc(ir_node *iv, iv_env *env) {
node_entry *e = get_irn_ne(iv, env);
return e->pscc;
-}
+} /* get_iv_scc */
/**
* Check if irn is an IV.
*/
static ir_node *is_iv(ir_node *irn, iv_env *env) {
return get_irn_ne(irn, env)->header;
-}
+} /* is_iv */
/**
* Check if irn is a region constant.
ir_node *block = get_nodes_block(irn);
return (block != header_block) && block_dominates(block, header_block);
-}
+} /* is_rc */
/**
* Set compare function for the quad set.
(void) size;
return c1->code != c2->code || c1->op1 != c2->op1 || c1->op2 != c2->op2;
-}
+} /* quad_cmp */
/**
* Check if an reduced operation was already calculated.
if (entry)
return entry->res;
return NULL;
-}
+} /* search */
/**
* Add an reduced operation.
set_insert(env->quad_map, &key, sizeof(key),
(code * 9) ^ HASH_PTR(op1) ^HASH_PTR(op2));
-}
+} /* add */
/**
* Find a location where to place a bin-op whose operands are in
return block2;
assert(block_dominates(block2, block1));
return block1;
-}
+} /* find_location */
/**
* Create a node that executes an op1 code op1 operation.
result = NULL;
}
return result;
-}
+} /* do_apply */
/**
* The Apply operation.
}
}
return result;
-}
+} /* apply */
/**
* The Reduce operation.
ir_opcode code = get_irn_opcode(orig);
ir_node *result = search(code, iv, rc, env);
+ /* check if we have already done this operation on the iv */
if (result == NULL) {
node_entry *e, *iv_e;
- int i, n;
+ int i;
ir_mode *mode = get_irn_mode(orig);
result = exact_copy(iv);
- /* Beware: we must always create a new induction variable with the same mode
- as the node we are replacing. Especially this means the mode might be changed
- from P to I and back. This is always possible, because we have only Phi, Add
- and Sub nodes. */
- set_irn_mode(result, mode);
+ if (get_irn_mode(result) != mode) {
+ /*
+ * Beware: we must always create a new induction variable with the same mode
+ * as the node we are replacing. Especially this means the mode might be changed
+ * from P to I and back. This is always possible, because we have only Phi, Add
+ * and Sub nodes.
+ * However, this might lead to AddIs(Iu,Is) which we must fix. The best way to do this
+ * seems to be a post-pass, or we might end with useless Conv's.
+ */
+ set_irn_mode(result, mode);
+ env->need_postpass = 1;
+ }
add(code, iv, rc, result, env);
DB((dbg, LEVEL_3, " Created new %+F for %+F (%s %+F)\n", result, iv,
get_irn_opname(orig), rc));
/* create the LFTR edge */
LFTR_add(iv, result, code, rc, env);
- n = get_irn_arity(result);
- for (i = 0; i < n; ++i) {
+ for (i = get_irn_arity(result) - 1; i >= 0; --i) {
ir_node *o = get_irn_n(result, i);
e = get_irn_ne(o, env);
o = apply(iv_e->header, orig, o, rc, env);
set_irn_n(result, i, o);
}
- }
- else {
+ } else {
DB((dbg, LEVEL_3, " Already Created %+F for %+F (%s %+F)\n", result, iv,
get_irn_opname(orig), rc));
}
return result;
-}
+} /* reduce */
/**
* Update the scc for a newly created IV.
} while (! waitq_empty(wq));
del_waitq(wq);
DB((dbg, LEVEL_2, "\n"));
-}
+} /* update_scc */
/**
- * The Replace operation.
+ * The Replace operation. We found a node representing iv (+,-,*) rc
+ * that can be removed by replacing the induction variable iv by a new
+ * one that 'applies' the operation 'irn'.
*
* @param irn the node that will be replaced
* @param iv the induction variable
return 1;
}
return 0;
-}
+} /* replace */
#if 0
/**
}
}
return 0;
-}
+} /* is_x86_shift_const */
#endif
/**
* Check if an IV represents a counter with constant limits.
+ *
+ * @param iv any node of the induction variable
+ * @param env the environment
*/
static int is_counter_iv(ir_node *iv, iv_env *env) {
node_entry *e = get_irn_ne(iv, env);
pscc->incr = get_Const_tarval(have_incr);
pscc->code = code;
return code != iro_Bad;
-}
+} /* is_counter_iv */
/**
* Check the users of an induction variable for register pressure.
+ *
+ * @param iv any node of the induction variable
+ * @param env the environment
+ *
+ * @return non-zero if the register pressure is estimated
+ * to not increase, zero else
*/
static int check_users_for_reg_pressure(ir_node *iv, iv_env *env) {
ir_node *irn, *header;
*
* For now our capabilities for doing linear function test
* are limited, so check if the iv has the right form: Only ONE
- * phi, only one Add/Sub with a Const
+ * Phi, only one Add/Sub with a Const.
*/
if (! is_counter_iv(iv, env))
return 0;
* to do a linear function test replacement, so go on.
*/
return 1;
-}
+} /* check_users_for_reg_pressure */
/**
* Check if a node can be replaced (+, -, *).
}
if (iv) {
- if (env->flags & osr_flag_keep_reg_pressure) {
+ if (env->osr_flags & osr_flag_keep_reg_pressure) {
if (! check_users_for_reg_pressure(iv, env))
return 0;
}
break;
}
return 0;
-}
+} /* check_replace */
/**
* Check which SCC's are induction variables.
next = e->next;
e->header = NULL;
}
-}
+} /* classify_iv */
/**
- * Process a SCC for the operator strength reduction.
+ * Process an SCC for the operator strength reduction.
*
* @param pscc the SCC
* @param env the environment
ir_node *irn, *next;
DB((dbg, LEVEL_4, " SCC at %p:\n ", pscc));
- for (irn = pscc->head; irn; irn = next) {
+ for (irn = pscc->head; irn != NULL; irn = next) {
node_entry *e = get_irn_link(irn);
next = e->next;
} else {
classify_iv(pscc, env);
}
-}
+} /* process_scc */
/**
* If an SCC is a Phi only cycle, remove it.
+ *
+ * @param pscc an SCC that consists of Phi nodes only
+ * @param env the environment
*/
static void remove_phi_cycle(scc *pscc, iv_env *env) {
ir_node *irn, *next;
exchange(irn, out_rc);
}
++env->replaced;
-}
+} /* remove_phi_cycle */
/**
- * Process a SCC for the Phi cycle removement.
+ * Process a SCC for the Phi cycle remove.
*
* @param pscc the SCC
* @param env the environment
if (e->next != NULL)
remove_phi_cycle(pscc, env);
-}
+} /* process_phi_only_scc */
/**
env->stack[env->tos++] = n;
e = get_irn_ne(n, env);
e->in_stack = 1;
-}
+} /* push */
/**
- * pop a node from the stack
+ * Pop a node from the stack.
*
* @param env the environment
*
* @return The topmost node
*/
-static ir_node *pop(iv_env *env)
-{
+static ir_node *pop(iv_env *env) {
ir_node *n = env->stack[--env->tos];
node_entry *e = get_irn_ne(n, env);
e->in_stack = 0;
return n;
-}
+} /* pop */
/**
* Do Tarjan's SCC algorithm and drive OSR.
* @param irn start at this node
* @param env the environment
*/
-static void dfs(ir_node *irn, iv_env *env)
-{
+static void dfs(ir_node *irn, iv_env *env) {
int i, n;
node_entry *node = get_irn_ne(irn, env);
if (!irn_visited(pred))
dfs(pred, env);
}
- }
- else {
+ } else {
ir_node *block = get_nodes_block(irn);
node->DFSnum = env->nextDFSnum++;
env->process_scc(pscc, env);
}
}
-}
+} /* dfs */
/**
* Do the DFS by starting at the End node of a graph.
*/
static void do_dfs(ir_graph *irg, iv_env *env) {
ir_graph *rem = current_ir_graph;
- ir_node *end = get_irg_end(irg);
- int i, n;
+ ir_node *end = get_irg_end(irg);
+ int i;
ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
dfs(end, env);
/* visit the keep-alives */
- n = get_End_n_keepalives(end);
- for (i = 0; i < n; ++i) {
+ for (i = get_End_n_keepalives(end) - 1; i >= 0; --i) {
ir_node *ka = get_End_keepalive(end, i);
if (!irn_visited(ka))
ir_free_resources(irg, IR_RESOURCE_IRN_VISITED);
current_ir_graph = rem;
-}
+} /* do_dfs */
/**
* Post-block-walker: assign the post-order number.
node_entry *e = get_irn_ne(block, env);
e->POnum = env->POnum++;
-}
-
-/**
- * Follows the LFTR edges and return the last node in the chain.
- *
- * @param irn the node that should be followed
- * @param env the IV environment
- *
- * @note
- * In the current implementation only the last edge is stored, so
- * only one chain exists. That's why we might miss some opportunities.
- */
-static ir_node *followEdges(ir_node *irn, iv_env *env) {
- for (;;) {
- LFTR_edge *e = LFTR_find(irn, env);
- if (e)
- irn = e->dst;
- else
- return irn;
- }
-}
+} /* assign_po */
/**
* Apply one LFTR edge operation.
* only one chain exists. That's why we might miss some opportunities.
*/
static ir_node *applyOneEdge(ir_node *iv, ir_node *rc, LFTR_edge *e, iv_env *env) {
- if (env->flags & osr_flag_lftr_with_ov_check) {
+ if (env->osr_flags & osr_flag_lftr_with_ov_check) {
tarval *tv_l, *tv_r, *tv, *tv_init, *tv_incr;
tarval_int_overflow_mode_t ovmode;
scc *pscc;
/* overflow can only be decided for Consts */
if (! is_Const(e->rc)) {
+ if (e->code == iro_Add && mode_is_reference(get_irn_mode(e->rc))) {
+ /* However we allow ONE Pointer Add, as pointer arithmetic with wrap
+ around is undefined anyway */
+ return do_apply(e->code, NULL, rc, e->rc, get_irn_mode(e->rc));
+ }
DB((dbg, LEVEL_4, " = UNKNOWN (%+F)", e->rc));
return NULL;
}
DB((dbg, LEVEL_4, " = OVERFLOW"));
return NULL;
}
- return new_Const(get_tarval_mode(tv), tv);
+ return new_Const(tv);
}
- return do_apply(e->code, NULL, rc, e->rc, get_irn_mode(rc));
-}
+ return do_apply(e->code, NULL, rc, e->rc, get_irn_mode(e->dst));
+} /* applyOneEdge */
/**
* Applies the operations represented by the LFTR edges to a
* Return NULL if the transformation cannot be done safely without
* an Overflow.
*
- * @param iv the IV node that starts the LFTR edge chain
+ * @param pIV points to the IV node that starts the LFTR edge chain
+ * after translation points to the new IV
* @param rc the region constant that should be translated
* @param env the IV environment
*
* @return the translated region constant or NULL
* if the translation was not possible
*/
-static ir_node *applyEdges(ir_node *iv, ir_node *rc, iv_env *env) {
- if (env->flags & osr_flag_lftr_with_ov_check) {
+static ir_node *applyEdges(ir_node **pIV, ir_node *rc, iv_env *env) {
+ ir_node *iv = *pIV;
+ if (env->osr_flags & osr_flag_lftr_with_ov_check) {
/* overflow can only be decided for Consts */
if (! is_counter_iv(iv, env)) {
DB((dbg, LEVEL_4, "not counter IV\n", rc));
for (; rc;) {
LFTR_edge *e = LFTR_find(iv, env);
- if (e) {
+ if (e != NULL) {
rc = applyOneEdge(iv, rc, e, env);
iv = e->dst;
- }
- else
+ } else
break;
}
DB((dbg, LEVEL_3, "\n"));
+ *pIV = iv;
return rc;
-}
+} /* applyEdges */
/**
* Walker, finds Cmp(iv, rc) or Cmp(rc, iv)
if (liv && is_rc(right, liv)) {
iv = left; rc = right;
- nright = applyEdges(iv, rc, env);
- if (nright && nright != rc) {
- nleft = followEdges(iv, env);
- }
+ nright = applyEdges(&iv, rc, env);
+ nleft = iv;
}
else if (riv && is_rc(left, riv)) {
iv = right; rc = left;
- nleft = applyEdges(iv, rc, env);
- if (nleft && nleft != rc) {
- nright = followEdges(iv, env);
- }
+ nleft = applyEdges(&iv, rc, env);
+ nright = iv;
}
if (nleft && nright) {
set_Cmp_right(cmp, nright);
++env->lftr_replaced;
}
-}
+} /* do_lftr */
/**
* do linear function test replacement.
*/
static void lftr(ir_graph *irg, iv_env *env) {
irg_walk_graph(irg, NULL, do_lftr, env);
-}
+} /* lftr */
/**
* Pre-walker: set all node links to NULL and fix the
* block of Proj nodes.
*/
-static void clear_and_fix(ir_node *irn, void *env)
-{
- (void) env;
+static void clear_and_fix(ir_node *irn, void *env) {
+ int *moved = env;
set_irn_link(irn, NULL);
if (is_Proj(irn)) {
- ir_node *pred = get_Proj_pred(irn);
- set_nodes_block(irn, get_nodes_block(pred));
+ ir_node *pred = get_Proj_pred(irn);
+ ir_node *pred_block = get_nodes_block(pred);
+
+ if (get_nodes_block(irn) != pred_block) {
+ set_nodes_block(irn, pred_block);
+ *moved = 1;
+ }
}
-}
+} /* clear_and_fix */
-/* Performs Operator Strength Reduction for the passed graph. */
-void opt_osr(ir_graph *irg, unsigned flags) {
+
+/* Remove any Phi cycles with only one real input. */
+void remove_phi_cycles(ir_graph *irg) {
iv_env env;
ir_graph *rem;
- int edges;
-
- if (! get_opt_strength_red()) {
- /* only kill Phi cycles */
- remove_phi_cycles(irg);
- return;
- }
+ int projs_moved;
rem = current_ir_graph;
current_ir_graph = irg;
- FIRM_DBG_REGISTER(dbg, "firm.opt.osr");
+ FIRM_DBG_REGISTER(dbg, "firm.opt.remove_phi");
- DB((dbg, LEVEL_1, "Doing Operator Strength Reduction for %+F\n", irg));
+ DB((dbg, LEVEL_1, "Doing Phi cycle removement for %+F\n", irg));
obstack_init(&env.obst);
env.stack = NEW_ARR_F(ir_node *, 128);
env.tos = 0;
env.nextDFSnum = 0;
env.POnum = 0;
- env.quad_map = new_set(quad_cmp, 64);
- env.lftr_edges = new_set(LFTR_cmp, 64);
+ env.quad_map = NULL;
+ env.lftr_edges = NULL;
env.replaced = 0;
env.lftr_replaced = 0;
- env.flags = flags;
- env.process_scc = process_scc;
+ env.osr_flags = 0;
+ env.need_postpass = 0;
+ env.process_scc = process_phi_only_scc;
/* Clear all links and move Proj nodes into the
the same block as it's predecessors.
This can improve the placement of new nodes.
*/
- irg_walk_graph(irg, NULL, clear_and_fix, NULL);
-
- /* we need dominance */
- assure_doms(irg);
+ projs_moved = 0;
+ irg_walk_graph(irg, NULL, clear_and_fix, &projs_moved);
+ if (projs_moved)
+ set_irg_outs_inconsistent(irg);
- edges = edges_assure(irg);
+ /* we need outs for calculating the post order */
+ assure_irg_outs(irg);
/* calculate the post order number for blocks. */
- irg_block_edges_walk(get_irg_start_block(irg), NULL, assign_po, &env);
+ irg_out_block_walk(get_irg_start_block(irg), NULL, assign_po, &env);
/* calculate the SCC's and drive OSR. */
+ ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK);
do_dfs(irg, &env);
+ ir_free_resources(irg, IR_RESOURCE_IRN_LINK);
if (env.replaced) {
- /* try linear function test replacements */
- //lftr(irg, &env); // currently buggy :-(
- (void) lftr;
-
set_irg_outs_inconsistent(irg);
- DB((dbg, LEVEL_1, "Replacements: %u + %u (lftr)\n\n", env.replaced, env.lftr_replaced));
+ DB((dbg, LEVEL_1, "remove_phi_cycles: %u Cycles removed\n\n", env.replaced));
}
- del_set(env.lftr_edges);
- del_set(env.quad_map);
DEL_ARR_F(env.stack);
obstack_free(&env.obst, NULL);
- if (! edges)
- edges_deactivate(irg);
-
current_ir_graph = rem;
-}
+} /* remove_phi_cycles */
-/* Remove any Phi cycles with only one real input. */
-void remove_phi_cycles(ir_graph *irg) {
+/**
+ * Post-walker: fix Add and Sub nodes that where results of I<->P conversions.
+ */
+static void fix_adds_and_subs(ir_node *irn, void *ctx) {
+ if (is_Add(irn)) {
+ ir_mode *mode = get_irn_mode(irn);
+
+ if (mode_is_int(mode)) {
+ ir_node *pred;
+
+ pred = get_Add_left(irn);
+ if (get_irn_mode(pred) != mode) {
+ ir_node *block = get_nodes_block(pred);
+
+ pred = new_r_Conv(current_ir_graph, block, pred, mode);
+ set_Add_left(irn, pred);
+ }
+ pred = get_Add_right(irn);
+ if (get_irn_mode(pred) != mode) {
+ ir_node *block = get_nodes_block(pred);
+
+ pred = new_r_Conv(current_ir_graph, block, pred, mode);
+ set_Add_right(irn, pred);
+ }
+ }
+ } else if (is_Sub(irn)) {
+ ir_mode *mode = get_irn_mode(irn);
+
+ if (mode_is_int(mode)) {
+ ir_node *left = get_Sub_left(irn);
+ ir_node *right = get_Sub_right(irn);
+ ir_mode *l_mode = get_irn_mode(left);
+ ir_mode *r_mode = get_irn_mode(right);
+
+ if (mode_is_int(l_mode) && mode_is_int(r_mode)) {
+ if (l_mode != mode) {
+ ir_node *block = get_nodes_block(left);
+
+ left = new_r_Conv(current_ir_graph, block, left, mode);
+ set_Sub_left(irn, left);
+ }
+ if (r_mode != mode) {
+ ir_node *block = get_nodes_block(right);
+
+ right = new_r_Conv(current_ir_graph, block, right, mode);
+ set_Sub_right(irn, right);
+ }
+ }
+ }
+ }
+} /* fix_adds_and_subs */
+
+/* Performs Operator Strength Reduction for the passed graph. */
+void opt_osr(ir_graph *irg, unsigned flags) {
iv_env env;
ir_graph *rem;
+ int edges;
+ int projs_moved;
+
+ if (! get_opt_strength_red()) {
+ /* only kill Phi cycles */
+ remove_phi_cycles(irg);
+ return;
+ }
rem = current_ir_graph;
current_ir_graph = irg;
- FIRM_DBG_REGISTER(dbg, "firm.opt.remove_phi");
+ FIRM_DBG_REGISTER(dbg, "firm.opt.osr");
- DB((dbg, LEVEL_1, "Doing Phi cycle removement for %+F\n", irg));
+ DB((dbg, LEVEL_1, "Doing Operator Strength Reduction for %+F\n", irg));
obstack_init(&env.obst);
env.stack = NEW_ARR_F(ir_node *, 128);
env.tos = 0;
env.nextDFSnum = 0;
env.POnum = 0;
- env.quad_map = NULL;
- env.lftr_edges = NULL;
+ env.quad_map = new_set(quad_cmp, 64);
+ env.lftr_edges = new_set(LFTR_cmp, 64);
env.replaced = 0;
env.lftr_replaced = 0;
- env.flags = 0;
- env.process_scc = process_phi_only_scc;
+ env.osr_flags = flags;
+ env.need_postpass = 0;
+ env.process_scc = process_scc;
/* Clear all links and move Proj nodes into the
the same block as it's predecessors.
This can improve the placement of new nodes.
*/
- irg_walk_graph(irg, NULL, clear_and_fix, NULL);
+ projs_moved = 0;
+ irg_walk_graph(irg, NULL, clear_and_fix, &projs_moved);
+ if (projs_moved)
+ set_irg_outs_inconsistent(irg);
- /* we need outs for calculating the post order */
- assure_irg_outs(irg);
+ /* we need dominance */
+ assure_doms(irg);
- /* calculate the post order number for blocks. */
- irg_out_block_walk(get_irg_start_block(irg), NULL, assign_po, &env);
+ edges = edges_assure(irg);
+
+ /* calculate the post order number for blocks by walking the out edges. */
+ assure_irg_outs(irg);
+ irg_block_edges_walk(get_irg_start_block(irg), NULL, assign_po, &env);
/* calculate the SCC's and drive OSR. */
+ ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK);
do_dfs(irg, &env);
if (env.replaced) {
+ if (env.need_postpass)
+ irg_walk_graph(irg, NULL, fix_adds_and_subs, &env);
+
+ /* try linear function test replacements */
+ lftr(irg, &env);
+
set_irg_outs_inconsistent(irg);
- DB((dbg, LEVEL_1, "remove_phi_cycles: %u Cycles removed\n\n", env.replaced));
+ DB((dbg, LEVEL_1, "Replacements: %u + %u (lftr)\n\n", env.replaced, env.lftr_replaced));
}
+ ir_free_resources(irg, IR_RESOURCE_IRN_LINK);
+ del_set(env.lftr_edges);
+ del_set(env.quad_map);
DEL_ARR_F(env.stack);
obstack_free(&env.obst, NULL);
+ if (! edges)
+ edges_deactivate(irg);
+
current_ir_graph = rem;
-}
+} /* opt_osr */