#include "debug.h"
#include "array_t.h"
#include "error.h"
+#include "irnodeset.h"
#include "tv_t.h"
partition_t *initial; /**< The initial partition. */
set *opcode2id_map; /**< The opcodeMode->id map. */
pmap *type2id_map; /**< The type->id map. */
+ ir_node **kept_memory; /**< Array of memory nodes that must be kept. */
int end_idx; /**< -1 for local and 0 for global congruences. */
int lambda_input; /**< Captured argument for lambda_partition(). */
unsigned modified:1; /**< Set, if the graph was modified. */
/** Type of the what function. */
typedef void *(*what_func)(const node_t *node, environment_t *env);
-#define get_irn_node(follower) ((node_t *)get_irn_link(follower))
-#define set_irn_node(follower, node) set_irn_link(follower, node)
+#define get_irn_node(irn) ((node_t *)get_irn_link(irn))
+#define set_irn_node(irn, node) set_irn_link(irn, node)
/* we do NOT use tarval_unreachable here, instead we use Top for this purpose */
#undef tarval_unreachable
static void exchange_leader(ir_node *irn, ir_node *leader) {
ir_mode *mode = get_irn_mode(irn);
if (mode != get_irn_mode(leader)) {
- /* The conv is a no-op, so we are fre to place in
+ /* The conv is a no-op, so we are free to place it
* either in the block of the leader OR in irn's block.
* Probably placing it into leaders block might reduce
* the number of Conv due to CSE. */
leader = new_rd_Conv(dbg, current_ir_graph, block, leader, mode);
}
exchange(irn, leader);
-}
+} /* exchange_leader */
+
+/**
+ * Check, if all users of a mode_M node are dead. Use
+ * the Def-Use edges for this purpose, as they still
+ * reflect the situation.
+ */
+static int all_users_are_dead(const ir_node *irn) {
+ int i, n = get_irn_n_outs(irn);
+
+ for (i = 1; i <= n; ++i) {
+ const ir_node *succ = irn->out[i].use;
+ const ir_node *block = get_nodes_block(succ);
+ const node_t *bl = get_irn_node(block);
+ const node_t *node;
+
+ if (bl->type.tv == tarval_unreachable) {
+ /* block is unreachable */
+ continue;
+ }
+ node = get_irn_node(succ);
+ if (node->type.tv != tarval_top) {
+ /* found a reachable user */
+ return 0;
+ }
+ }
+ /* all users are unreachable */
+ return 1;
+} /* all_user_are_dead */
+
+/**
+ * Walker: Find reachable mode_M nose that have only
+ * unreachable users. These nodes must be kept later.
+ */
+static void find_kept_memory(ir_node *irn, void *ctx) {
+ environment_t *env = ctx;
+ node_t *node, *block;
+
+ if (is_Block(irn)) {
+ return;
+ }
+ if (get_irn_mode(irn) != mode_M)
+ return;
+
+ block = get_irn_node(get_nodes_block(irn));
+ if (block->type.tv == tarval_unreachable)
+ return;
+
+ node = get_irn_node(irn);
+ if (node->type.tv == tarval_top)
+ return;
+
+ /* ok, we found a live memory node. */
+ if (all_users_are_dead(irn)) {
+ DB((dbg, LEVEL_1, "%+F must be kept\n", irn));
+ ARR_APP1(ir_node *, env->kept_memory, irn);
+ }
+} /* find_kept_memory */
/**
* Post-Walker, apply the analysis results;
if (is_Block(irn) || is_End(irn) || is_Bad(irn)) {
/* blocks already handled, do not touch the End node */
} else {
- node_t *block = get_irn_node(get_nodes_block(irn));
+ node_t *block = get_irn_node(get_nodes_block(irn));
if (block->type.tv == tarval_unreachable) {
ir_node *bad = get_irg_bad(current_ir_graph);
SET(Max);
if (op_Min != NULL)
SET(Min);
-
} /* set_compute_functions */
+/**
+ * Add memory keeps.
+ */
+static void add_memory_keeps(ir_node **kept_memory, int len) {
+ ir_node *end = get_irg_end(current_ir_graph);
+ int i;
+ ir_nodeset_t set;
+
+ ir_nodeset_init(&set);
+
+ /* check, if those nodes are already kept */
+ for (i = get_End_n_keepalives(end) - 1; i >= 0; --i)
+ ir_nodeset_insert(&set, get_End_keepalive(end, i));
+
+ for (i = len - 1; i >= 0; --i) {
+ ir_node *ka = kept_memory[i];
+
+ if (! ir_nodeset_contains(&set, ka)) {
+ add_End_keepalive(end, ka);
+ }
+ }
+ ir_nodeset_destroy(&set);
+} /* add_memory_keeps */
+
void combo(ir_graph *irg) {
environment_t env;
ir_node *initial_bl;
node_t *start;
ir_graph *rem = current_ir_graph;
+ int len;
current_ir_graph = irg;
#endif
env.opcode2id_map = new_set(cmp_opcode, iro_Last * 4);
env.type2id_map = pmap_create();
+ env.kept_memory = NEW_ARR_F(ir_node *, 0);
env.end_idx = get_opt_global_cse() ? 0 : -1;
env.lambda_input = 0;
env.modified = 0;
#endif
/* apply the result */
+
+ /* check, which nodes must be kept */
+ irg_walk_graph(irg, NULL, find_kept_memory, &env);
+
+ /* kill unreachable control flow */
irg_block_walk_graph(irg, NULL, apply_cf, &env);
/* Kill keep-alives of dead blocks: this speeds up apply_result()
* and fixes assertion because dead cf to dead blocks is NOT removed by
apply_end(get_irg_end(irg), &env);
irg_walk_graph(irg, NULL, apply_result, &env);
+ len = ARR_LEN(env.kept_memory);
+ if (len > 0)
+ add_memory_keeps(env.kept_memory, len);
+
if (env.unopt_cf) {
DB((dbg, LEVEL_1, "Unoptimized Control Flow left"));
}
/* remove the partition hook */
DEBUG_ONLY(set_dump_node_vcgattr_hook(NULL));
+ DEL_ARR_F(env.kept_memory);
pmap_destroy(env.type2id_map);
del_set(env.opcode2id_map);
obstack_free(&env.obst, NULL);