* Copyright: (c) 1998-2004 Universit\81ät Karlsruhe
* Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
*/
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#ifdef HAVE_ALLOCA_H
+#include <alloca.h>
+#endif
+#ifdef HAVE_MALLOC_H
+#include <malloc.h>
+#endif
+#ifdef HAVE_STRING_H
+# include <string.h>
+#endif
+
# include "irnode_t.h"
# include "irgraph_t.h"
# include "irmode_t.h"
# include "iropt_dbg.h"
# include "irflag_t.h"
# include "array.h"
-# include "firmstat.h"
+# include "irhooks.h"
+# include "irtools.h"
+# include "opt_polymorphy.h"
+
+#ifdef DO_CACHEOPT
+#include "cacheopt/cachesim.h"
+#endif
#undef IMAX
#define IMAX(a,b) ((a) > (b) ? (a) : (b))
#define MAX_PROJ IMAX(pn_Load_max, pn_Store_max)
+enum changes_t {
+ DF_CHANGED = 1, /**< data flow changed */
+ CF_CHANGED = 2, /**< control flow changed */
+};
+
/**
* walker environment
*/
typedef struct _walk_env_t {
struct obstack obst; /**< list of all stores */
- int changes;
+ unsigned changes; /**< a bitmask of graph changes */
} walk_env_t;
+/**
+ * flags for Load/Store
+ */
+enum ldst_flags_t {
+ LDST_VISITED = 1 /**< if set, this Load/Store is already visited */
+};
+
/**
* a Load/Store info
*/
typedef struct _ldst_info_t {
- ir_node *projs[MAX_PROJ]; /**< list of Proj's of this node */
- ir_node *exc_block; /**< the exception block if available */
- int exc_idx; /**< predecessor index in the exception block */
+ ir_node *projs[MAX_PROJ]; /**< list of Proj's of this node */
+ ir_node *exc_block; /**< the exception block if available */
+ int exc_idx; /**< predecessor index in the exception block */
+ unsigned flags; /**< flags */
+ unsigned visited; /**< visited counter for breaking loops */
} ldst_info_t;
/**
*/
enum block_flags_t {
BLOCK_HAS_COND = 1, /**< Block has conditional control flow */
- BLOCK_HAS_EXC = 2 /**< Block has exceptionl control flow */
+ BLOCK_HAS_EXC = 2 /**< Block has exceptional control flow */
};
/**
unsigned flags; /**< flags for the block */
} block_info_t;
-/**
- * walker, clears all links first
- */
-static void init_links(ir_node *n, void *env)
-{
- set_irn_link(n, NULL);
-}
+/** the master visited flag for loop detection. */
+static unsigned master_visited = 0;
+
+#define INC_MASTER() ++master_visited
+#define MARK_NODE(info) (info)->visited = master_visited
+#define NODE_VISITED(info) (info)->visited >= master_visited
/**
* get the Load/Store info of a node
/**
* update the projection info for a Load/Store
*/
-static int update_projs(ldst_info_t *info, ir_node *proj)
+static unsigned update_projs(ldst_info_t *info, ir_node *proj)
{
long nr = get_Proj_proj(proj);
if (info->projs[nr]) {
/* there is already one, do CSE */
exchange(proj, info->projs[nr]);
- return 1;
+ return DF_CHANGED;
}
else {
info->projs[nr] = proj;
}
/**
- * update the exception block info for a Load/Store
+ * update the exception block info for a Load/Store node.
+ *
+ * @param info the load/store info struct
+ * @param block the exception handler block for this load/store
+ * @param pos the control flow input of the block
*/
-static int update_exc(ldst_info_t *info, ir_node *block, int pos)
+static unsigned update_exc(ldst_info_t *info, ir_node *block, int pos)
{
assert(info->exc_block == NULL && "more than one exception block found");
return 0;
}
-#define get_irn_out_n(node) (unsigned)get_irn_link(node)
-#define set_irn_out_n(node, n) set_irn_link(adr, (void *)(n))
+#define get_irn_out_n(node) (unsigned)PTR_TO_INT(get_irn_link(node))
+#define set_irn_out_n(node, n) set_irn_link(adr, INT_TO_PTR(n))
/**
* walker, collects all Load/Store/Proj nodes
*
- * walks form Start -> End
+ * walks from Start -> End
*/
static void collect_nodes(ir_node *node, void *env)
{
- ir_node *pred;
+ ir_op *op = get_irn_op(node);
+ ir_node *pred, *blk, *pred_blk;
ldst_info_t *ldst_info;
walk_env_t *wenv = env;
- if (get_irn_op(node) == op_Proj) {
+ if (op == op_Proj) {
ir_node *adr;
ir_op *op;
op = get_irn_op(pred);
if (op == op_Load) {
- adr = get_Load_ptr(pred);
ldst_info = get_ldst_info(pred, wenv);
wenv->changes |= update_projs(ldst_info, node);
- set_irn_out_n(adr, get_irn_out_n(adr) + 1);
+ if ((ldst_info->flags & LDST_VISITED) == 0) {
+ adr = get_Load_ptr(pred);
+ set_irn_out_n(adr, get_irn_out_n(adr) + 1);
+
+ ldst_info->flags |= LDST_VISITED;
+ }
+
+ /*
+ * Place the Proj's to the same block as the
+ * predecessor Load. This is always ok and prevents
+ * "non-SSA" form after optimizations if the Proj
+ * is in a wrong block.
+ */
+ blk = get_nodes_block(node);
+ pred_blk = get_nodes_block(pred);
+ if (blk != pred_blk) {
+ wenv->changes |= DF_CHANGED;
+ set_nodes_block(node, pred_blk);
+ }
}
else if (op == op_Store) {
- adr = get_Store_ptr(pred);
ldst_info = get_ldst_info(pred, wenv);
wenv->changes |= update_projs(ldst_info, node);
- set_irn_out_n(adr, get_irn_out_n(adr) + 1);
+ if ((ldst_info->flags & LDST_VISITED) == 0) {
+ adr = get_Store_ptr(pred);
+ set_irn_out_n(adr, get_irn_out_n(adr) + 1);
+
+ ldst_info->flags |= LDST_VISITED;
+ }
+
+ /*
+ * Place the Proj's to the same block as the
+ * predecessor Store. This is always ok and prevents
+ * "non-SSA" form after optimizations if the Proj
+ * is in a wrong block.
+ */
+ blk = get_nodes_block(node);
+ pred_blk = get_nodes_block(pred);
+ if (blk != pred_blk) {
+ wenv->changes |= DF_CHANGED;
+ set_nodes_block(node, pred_blk);
+ }
}
}
- else if (get_irn_op(node) == op_Block) { /* check, if it's an exception block */
- int i, n;
+ else if (op == op_Block) { /* check, if it's an exception block */
+ int i;
- for (i = 0, n = get_Block_n_cfgpreds(node); i < n; ++i) {
+ for (i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
ir_node *pred_block;
block_info_t *bl_info;
/* ignore Bad predecessors, they will be removed later */
if (is_Bad(pred))
- continue;
+ continue;
pred_block = get_nodes_block(pred);
bl_info = get_block_info(pred_block, wenv);
if (is_fragile_op(pred))
- bl_info->flags |= BLOCK_HAS_EXC;
- else if (is_forking_op(pred))
- bl_info->flags |= BLOCK_HAS_COND;
+ bl_info->flags |= BLOCK_HAS_EXC;
+ else if (is_irn_forking(pred))
+ bl_info->flags |= BLOCK_HAS_COND;
if (get_irn_op(pred) == op_Load || get_irn_op(pred) == op_Store) {
ldst_info = get_ldst_info(pred, wenv);
}
}
+/**
+ * Returns an entity if the address ptr points to a constant one.
+ */
+static entity *find_constant_entity(ir_node *ptr)
+{
+ for (;;) {
+ ir_op *op = get_irn_op(ptr);
+
+ if (op == op_SymConst && (get_SymConst_kind(ptr) == symconst_addr_ent)) {
+ return get_SymConst_entity(ptr);
+ }
+ else if (op == op_Sel) {
+ entity *ent = get_Sel_entity(ptr);
+ type *tp = get_entity_owner(ent);
+
+ /* Do not fiddle about polymorphy. */
+ if (is_Class_type(get_entity_owner(ent)) &&
+ ((get_entity_n_overwrites(ent) != 0) ||
+ (get_entity_n_overwrittenby(ent) != 0) ) )
+ return NULL;
+
+ if (variability_constant == get_entity_variability(ent))
+ return ent;
+
+ if (is_Array_type(tp)) {
+ /* check bounds */
+ int i, n;
+
+ for (i = 0, n = get_Sel_n_indexs(ptr); i < n; ++i) {
+ ir_node *bound;
+ tarval *tlower, *tupper;
+ ir_node *index = get_Sel_index(ptr, i);
+ tarval *tv = computed_value(index);
+
+ /* check if the index is constant */
+ if (tv == tarval_bad)
+ return NULL;
+
+ bound = get_array_lower_bound(tp, i);
+ tlower = computed_value(bound);
+ bound = get_array_upper_bound(tp, i);
+ tupper = computed_value(bound);
+
+ if (tlower == tarval_bad || tupper == tarval_bad)
+ return NULL;
+
+ if (tarval_cmp(tv, tlower) & pn_Cmp_Lt)
+ return NULL;
+ if (tarval_cmp(tupper, tv) & pn_Cmp_Lt)
+ return NULL;
+
+ /* ok, bounds check finished */
+ }
+ }
+
+ /* try next */
+ ptr = get_Sel_ptr(ptr);
+ }
+ else
+ return NULL;
+ }
+}
+
+/**
+ * Return the Selection index of a Sel node from dimension n
+ */
+static long get_Sel_array_index_long(ir_node *n, int dim) {
+ ir_node *index = get_Sel_index(n, dim);
+ assert(get_irn_op(index) == op_Const);
+ return get_tarval_long(get_Const_tarval(index));
+}
+
+/**
+ * Returns the accessed component graph path for an
+ * node computing an address.
+ *
+ * @param ptr the node computing the address
+ * @param depth current depth in steps upward from the root
+ * of the address
+ */
+static compound_graph_path *rec_get_accessed_path(ir_node *ptr, int depth) {
+ compound_graph_path *res = NULL;
+ entity *root, *field;
+ int path_len, pos;
+
+ if (get_irn_op(ptr) == op_SymConst) {
+ /* a SymConst. If the depth is 0, this is an access to a global
+ * entity and we don't need a component path, else we know
+ * at least it's length.
+ */
+ assert(get_SymConst_kind(ptr) == symconst_addr_ent);
+ root = get_SymConst_entity(ptr);
+ res = (depth == 0) ? NULL : new_compound_graph_path(get_entity_type(root), depth);
+ }
+ else {
+ assert(get_irn_op(ptr) == op_Sel);
+ /* it's a Sel, go up until we find the root */
+ res = rec_get_accessed_path(get_Sel_ptr(ptr), depth+1);
+
+ /* fill up the step in the path at the current position */
+ field = get_Sel_entity(ptr);
+ path_len = get_compound_graph_path_length(res);
+ pos = path_len - depth - 1;
+ set_compound_graph_path_node(res, pos, field);
+
+ if (is_Array_type(get_entity_owner(field))) {
+ assert(get_Sel_n_indexs(ptr) == 1 && "multi dim arrays not implemented");
+ set_compound_graph_path_array_index(res, pos, get_Sel_array_index_long(ptr, 0));
+ }
+ }
+ return res;
+}
+
+/** Returns an access path or NULL. The access path is only
+ * valid, if the graph is in phase_high and _no_ address computation is used.
+ */
+static compound_graph_path *get_accessed_path(ir_node *ptr) {
+ return rec_get_accessed_path(ptr, 0);
+}
+
/**
* optimize a Load
*/
-static int optimize_load(ir_node *load)
+static unsigned optimize_load(ir_node *load)
{
ldst_info_t *info = get_irn_link(load);
ir_mode *load_mode = get_Load_mode(load);
- ir_node *pred, *mem, *ptr;
- int res = 0;
+ ir_node *pred, *mem, *ptr, *new_node;
+ entity *ent;
+ unsigned res = 0;
+
+ /* do NOT touch volatile loads for now */
+ if (get_Load_volatility(load) == volatility_is_volatile)
+ return 0;
/* the address of the load to be optimized */
ptr = get_Load_ptr(load);
/*
- * Check if we can remove the exception form a Load:
- * this can be done, if the address is from an Sel(Alloc) and
- * the Sel type is a subtype of the alloc type.
+ * Check if we can remove the exception from a Load:
+ * This can be done, if the address is from an Sel(Alloc) and
+ * the Sel type is a subtype of the allocated type.
*
* This optimizes some often used OO constructs,
* like x = new O; x->t;
if (get_irn_op(ptr) == op_Sel) {
ir_node *mem = get_Sel_mem(ptr);
- if (get_irn_op(mem) == op_Alloc) {
+ if (get_irn_op(skip_Proj(mem)) == op_Alloc) {
/* ok, check the types */
entity *ent = get_Sel_entity(ptr);
type *s_type = get_entity_type(ent);
if (is_subclass_of(s_type, a_type)) {
/* ok, condition met: there can't be an exception because
- * alloc guarantees that enough memory was allocated */
+ * Alloc guarantees that enough memory was allocated */
exchange(info->projs[pn_Load_X_except], new_Bad());
info->projs[pn_Load_X_except] = NULL;
+ res |= CF_CHANGED;
}
}
}
- else if (get_irn_op(ptr) == op_Alloc) {
+ else if ((get_irn_op(skip_Proj(ptr)) == op_Alloc) ||
+ ((get_irn_op(ptr) == op_Cast) && (get_irn_op(skip_Proj(get_Cast_op(ptr))) == op_Alloc))) {
/* simple case: a direct load after an Alloc. Firm Alloc throw
* an exception in case of out-of-memory. So, there is no way for an
* exception in this load.
*/
exchange(info->projs[pn_Load_X_except], new_Bad());
info->projs[pn_Load_X_except] = NULL;
+ res |= CF_CHANGED;
}
}
- /* do NOT touch volatile loads for now */
- if (get_Load_volatility(load) == volatility_is_volatile)
- return 0;
+ /* the mem of the Load. Must still be returned after optimization */
+ mem = get_Load_mem(load);
if (! info->projs[pn_Load_res] && ! info->projs[pn_Load_X_except]) {
/* a Load which value is neither used nor exception checked, remove it */
- mem = get_Load_mem(load);
exchange(info->projs[pn_Load_M], mem);
- return 1;
+ return res | DF_CHANGED;
}
- /* the mem of the Load. Must still be returned after optimization */
- mem = get_Load_mem(load);
-
- if ((get_irn_opcode(ptr) == iro_SymConst) && (get_SymConst_kind(ptr) == symconst_addr_ent)) {
- entity *ent = get_SymConst_entity(ptr);
-
- assert(mode_is_reference(get_irn_mode(ptr)));
+ /* Load from a constant polymorphic field, where we can resolve
+ polymorphy. */
+ new_node = transform_node_Load(load);
+ if (new_node != load) {
+ if (info->projs[pn_Load_M]) {
+ exchange(info->projs[pn_Load_M], mem);
+ info->projs[pn_Load_M] = NULL;
+ }
+ if (info->projs[pn_Load_X_except]) {
+ exchange(info->projs[pn_Load_X_except], new_Bad());
+ info->projs[pn_Load_X_except] = NULL;
+ }
+ if (info->projs[pn_Load_res])
+ exchange(info->projs[pn_Load_res], new_node);
+ return res | DF_CHANGED;
+ }
+ /* check if we can determine the entity that will be loaded */
+ ent = find_constant_entity(ptr);
+ if (ent) {
if ((allocation_static == get_entity_allocation(ent)) &&
(visibility_external_allocated != get_entity_visibility(ent))) {
/* a static allocation that is not external: there should be NO exception
if (info->projs[pn_Load_X_except]) {
exchange(info->projs[pn_Load_X_except], new_Bad());
info->projs[pn_Load_X_except] = NULL;
+ res |= CF_CHANGED;
}
if (variability_constant == get_entity_variability(ent)
- && is_atomic_entity(ent)) { /* Might not be atomic after
- lowering of Sels. In this
- case we could also load, but
- it's more complicated. */
+ && is_atomic_entity(ent)) {
+ /* Might not be atomic after
+ lowering of Sels. In this
+ case we could also load, but
+ it's more complicated. */
/* more simpler case: we load the content of a constant value:
* replace it by the constant itself
*/
/* no memory */
- if (info->projs[pn_Load_M])
+ if (info->projs[pn_Load_M]) {
exchange(info->projs[pn_Load_M], mem);
+ res |= DF_CHANGED;
+ }
/* no result :-) */
- if (info->projs[pn_Load_res])
- exchange(info->projs[pn_Load_res], copy_const_value(get_atomic_ent_value(ent)));
+ if (info->projs[pn_Load_res]) {
+ if (is_atomic_entity(ent)) {
+ ir_node *c = copy_const_value(get_atomic_ent_value(ent));
- return 1;
+ DBG_OPT_RC(load, c);
+ exchange(info->projs[pn_Load_res], c);
+ return DF_CHANGED | res;
+ }
+ }
}
+ else if (variability_constant == get_entity_variability(ent)) {
+ compound_graph_path *path = get_accessed_path(ptr);
+
+ if (path) {
+ ir_node *c;
+
+ assert(is_proper_compound_graph_path(path, get_compound_graph_path_length(path)-1));
+ /*
+ {
+ int j;
+ for (j = 0; j < get_compound_graph_path_length(path); ++j) {
+ entity *node = get_compound_graph_path_node(path, j);
+ fprintf(stdout, ".%s", get_entity_name(node));
+ if (is_Array_type(get_entity_owner(node)))
+ fprintf(stdout, "[%d]", get_compound_graph_path_array_index(path, j));
+ }
+ printf("\n");
+ }
+ */
+
+ c = get_compound_ent_value_by_path(ent, path);
+ free_compound_graph_path(path);
- /* we changed the irg, but try further */
- res = 1;
+ /* printf(" cons: "); DDMN(c); */
+
+ if (info->projs[pn_Load_M]) {
+ exchange(info->projs[pn_Load_M], mem);
+ res |= DF_CHANGED;
+ }
+ if (info->projs[pn_Load_res]) {
+ exchange(info->projs[pn_Load_res], copy_const_value(c));
+ return res | DF_CHANGED;
+ }
+ }
+ else {
+ /* We can not determine a correct access path. E.g., in jack, we load
+ a byte from an object to generate an exception. Happens in test program
+ Reflectiontest.
+ printf(">>>>>>>>>>>>> Found access to constant entity %s in function %s\n", get_entity_name(ent),
+ get_entity_name(get_irg_entity(current_ir_graph)));
+ printf(" load: "); DDMN(load);
+ printf(" ptr: "); DDMN(ptr);
+ */
+ }
+ }
}
}
/* Check, if the address of this load is used more than once.
* If not, this load cannot be removed in any case. */
if (get_irn_out_n(ptr) <= 1)
- return 0;
+ return res;
- /* follow the memory chain as long as there are only Loads */
- for (pred = skip_Proj(mem); ; pred = skip_Proj(get_Load_mem(pred))) {
+ /*
+ * follow the memory chain as long as there are only Loads
+ * and try to replace current Load or Store by a previous one.
+ * Note that in unreachable loops it might happen that we reach
+ * load again, as well as we can fall into a cycle.
+ * We break such cycles using a special visited flag.
+ */
+ INC_MASTER();
+ for (pred = skip_Proj(mem); load != pred; pred = skip_Proj(get_Load_mem(pred))) {
+ ldst_info_t *pred_info = get_irn_link(pred);
/*
* BEWARE: one might think that checking the modes is useless, because
* if the pointers are identical, they refer to the same object.
- * This is only true in strong typed languages, not is C were the following
+ * This is only true in strong typed languages, not in C were the following
* is possible a = *(type1 *)p; b = *(type2 *)p ...
*/
if (get_irn_op(pred) == op_Store && get_Store_ptr(pred) == ptr &&
get_irn_mode(get_Store_value(pred)) == load_mode) {
- ldst_info_t *pred_info = get_irn_link(pred);
-
/*
* a Load immediately after a Store -- a read after write.
* We may remove the Load, if both Load & Store does not have an exception handler
* OR they are in the same block. In the latter case the Load cannot
* throw an exception when the previous Store was quiet.
*
- * Why we need to check for Store Exc? If the Store cannot be executed (ROM)
- * the exception handler might simply jump into the load block :-(
+ * Why we need to check for Store Exception? If the Store cannot
+ * be executed (ROM) the exception handler might simply jump into
+ * the load block :-(
* We could make it a little bit better if we would know that the exception
* handler of the Store jumps directly to the end...
*/
if ((!pred_info->projs[pn_Store_X_except] && !info->projs[pn_Load_X_except]) ||
get_nodes_block(load) == get_nodes_block(pred)) {
- DBG_OPT_RAW(pred, load);
- exchange( info->projs[pn_Load_res], get_Store_value(pred) );
+ ir_node *value = get_Store_value(pred);
+ DBG_OPT_RAW(load, value);
if (info->projs[pn_Load_M])
exchange(info->projs[pn_Load_M], mem);
/* no exception */
- if (info->projs[pn_Load_X_except])
+ if (info->projs[pn_Load_X_except]) {
exchange( info->projs[pn_Load_X_except], new_Bad());
- return 1;
+ res |= CF_CHANGED;
+ }
+
+ if (info->projs[pn_Load_res])
+ exchange(info->projs[pn_Load_res], value);
+
+ return res | DF_CHANGED;
}
}
else if (get_irn_op(pred) == op_Load && get_Load_ptr(pred) == ptr &&
* OR they are in the same block. In the later case the Load cannot
* throw an exception when the previous Load was quiet.
*
- * Here, there is no need to check if the previos Load has an exception hander because
- * they would have exact the same exception...
+ * Here, there is no need to check if the previous Load has an exception
+ * hander because they would have exact the same exception...
*/
if (! info->projs[pn_Load_X_except] || get_nodes_block(load) == get_nodes_block(pred)) {
- ldst_info_t *pred_info = get_irn_link(pred);
-
- DBG_OPT_RAR(pred, load);
+ DBG_OPT_RAR(load, pred);
if (pred_info->projs[pn_Load_res]) {
/* we need a data proj from the previous load for this optimization */
- exchange( info->projs[pn_Load_res], pred_info->projs[pn_Load_res] );
+ if (info->projs[pn_Load_res])
+ exchange(info->projs[pn_Load_res], pred_info->projs[pn_Load_res]);
+
if (info->projs[pn_Load_M])
exchange(info->projs[pn_Load_M], mem);
}
if (info->projs[pn_Load_res]) {
set_Proj_pred(info->projs[pn_Load_res], pred);
set_nodes_block(info->projs[pn_Load_res], get_nodes_block(pred));
+ pred_info->projs[pn_Load_res] = info->projs[pn_Load_res];
}
if (info->projs[pn_Load_M]) {
/* Actually, this if should not be necessary. Construct the Loads
}
/* no exception */
- if (info->projs[pn_Load_X_except])
+ if (info->projs[pn_Load_X_except]) {
exchange(info->projs[pn_Load_X_except], new_Bad());
+ res |= CF_CHANGED;
+ }
- return 1;
+ return res |= DF_CHANGED;
}
}
/* follow only Load chains */
if (get_irn_op(pred) != op_Load)
break;
- }
+
+ /* check for cycles */
+ if (NODE_VISITED(pred_info))
+ break;
+ MARK_NODE(pred_info);
+ }
return res;
}
/**
* optimize a Store
*/
-static int optimize_store(ir_node *store)
+static unsigned optimize_store(ir_node *store)
{
ldst_info_t *info = get_irn_link(store);
ir_node *pred, *mem, *ptr, *value, *block;
ir_mode *mode;
- int res = 0;
+ unsigned res = 0;
if (get_Store_volatility(store) == volatility_is_volatile)
return 0;
mode = get_irn_mode(value);
/* follow the memory chain as long as there are only Loads */
- for (pred = skip_Proj(mem); ; pred = skip_Proj(get_Load_mem(pred))) {
+ INC_MASTER();
+ for (pred = skip_Proj(mem); pred != store; pred = skip_Proj(get_Load_mem(pred))) {
ldst_info_t *pred_info = get_irn_link(pred);
if (get_irn_op(pred) == op_Store && get_Store_ptr(pred) == ptr &&
if (get_Store_volatility(pred) != volatility_is_volatile && !pred_info->projs[pn_Store_X_except]) {
DBG_OPT_WAW(pred, store);
exchange( pred_info->projs[pn_Store_M], get_Store_mem(pred) );
- return 1;
+ return DF_CHANGED;
}
}
else if (get_irn_op(pred) == op_Load && get_Load_ptr(pred) == ptr &&
* We may remove the second Store, if it does not have an exception handler.
*/
if (! info->projs[pn_Store_X_except]) {
- DBG_OPT_WAR(pred, store);
+ DBG_OPT_WAR(store, pred);
exchange( info->projs[pn_Store_M], mem );
- return 1;
+ return DF_CHANGED;
}
}
/* follow only Load chains */
if (get_irn_op(pred) != op_Load)
break;
+
+ /* check for cycles */
+ if (NODE_VISITED(pred_info))
+ break;
+ MARK_NODE(pred_info);
}
return res;
}
/**
- * walker, optimizes Phi after Stores:
+ * walker, optimizes Phi after Stores to identical places:
* Does the following optimization:
+ * @verbatim
*
* val1 val2 val3 val1 val2 val3
* | | | \ | /
* Str Str Str \ | /
- * \ | / Phi
+ * \ | / PhiData
* \ | / |
* \ | / Str
- * Phi
+ * PhiM
*
- * This removes the number of stores and allows for predicated execution.
- * Moves Stores back to the end of a function which may be bad
+ * @endverbatim
+ * This reduces the number of stores and allows for predicated execution.
+ * Moves Stores back to the end of a function which may be bad.
*
- * Is only allowed if the predecessor blocks have only one successor.
+ * This is only possible if the predecessor blocks have only one successor.
*/
-static int optimize_phi(ir_node *phi, void *env)
+static unsigned optimize_phi(ir_node *phi, void *env)
{
walk_env_t *wenv = env;
int i, n;
- ir_node *store, *ptr, *block, *phiM, *phiD, *exc, *projM;
+ ir_node *store, *old_store, *ptr, *block, *phiM, *phiD, *exc, *projM;
ir_mode *mode;
ir_node **inM, **inD;
int *idx;
dbg_info *db = NULL;
ldst_info_t *info;
block_info_t *bl_info;
+ unsigned res = 0;
/* Must be a memory Phi */
if (get_irn_mode(phi) != mode_M)
return 0;
store = skip_Proj(get_Phi_pred(phi, 0));
+ old_store = store;
if (get_irn_op(store) != op_Store)
return 0;
- /* abort on bad blocks */
- if (is_Bad(get_nodes_block(store)))
+ /* abort on dead blocks */
+ if (is_Block_dead(get_nodes_block(store)))
return 0;
- /* check if the block has only one output */
+ /* check if the block has only one successor */
bl_info = get_irn_link(get_nodes_block(store));
if (bl_info->flags)
return 0;
if (get_irn_op(pred) != op_Store)
return 0;
- if (mode != get_irn_mode(get_Store_value(pred)) || ptr != get_Store_ptr(pred))
+ if (ptr != get_Store_ptr(pred) || mode != get_irn_mode(get_Store_value(pred)))
return 0;
info = get_irn_link(pred);
if (exc != info->exc_block)
return 0;
- /* abort on bad blocks */
- if (is_Bad(get_nodes_block(store)))
+ /* abort on dead blocks */
+ if (is_Block_dead(get_nodes_block(store)))
return 0;
- /* check if the block has only one output */
+ /* check if the block has only one successor */
bl_info = get_irn_link(get_nodes_block(store));
if (bl_info->flags)
return 0;
/*
* ok, when we are here, we found all predecessors of a Phi that
- * are Stores to the same address. That means whatever we do before
- * we enter the block of the Phi, we do a Store.
- * So, we can move the store to the current block:
+ * are Stores to the same address and size. That means whatever
+ * we do before we enter the block of the Phi, we do a Store.
+ * So, we can move the Store to the current block:
*
* val1 val2 val3 val1 val2 val3
* | | | \ | /
* | Str | | Str | | Str | \ | /
- * \ | / Phi
+ * \ | / PhiData
* \ | / |
* \ | / Str
- * Phi
+ * PhiM
*
* Is only allowed if the predecessor blocks have only one successor.
*/
/* fourth step: create the Store */
store = new_rd_Store(db, current_ir_graph, block, phiM, ptr, phiD);
+#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);
info = get_ldst_info(store, wenv);
if (n > 1) {
/* the exception block should be optimized as some inputs are identical now */
}
+
+ res |= CF_CHANGED;
}
- /* sixt step: replace old Phi */
+ /* sixth step: replace old Phi */
exchange(phi, projM);
- return 1;
+ return res | DF_CHANGED;
}
/**
- * walker, collects all Load/Store/Proj nodes
+ * walker, do the optiimizations
*/
static void do_load_store_optimize(ir_node *n, void *env)
{
walk_env_t env;
assert(get_irg_phase_state(irg) != phase_building);
+ assert(get_irg_pinned(irg) != op_pin_state_floats &&
+ "LoadStore optimization needs pinned graph");
if (!get_opt_redundant_LoadStore())
return;
env.changes = 0;
/* init the links, then collect Loads/Stores/Proj's in lists */
- irg_walk_graph(irg, init_links, collect_nodes, &env);
+ master_visited = 0;
+ irg_walk_graph(irg, firm_clear_link, collect_nodes, &env);
/* now we have collected enough information, optimize */
irg_walk_graph(irg, NULL, do_load_store_optimize, &env);
if (env.changes) {
if (get_irg_outs_state(current_ir_graph) == outs_consistent)
set_irg_outs_inconsistent(current_ir_graph);
+ }
- /* is this really needed: Yes, as exception block may get bad but this might be tested */
+ if (env.changes & CF_CHANGED) {
+ /* is this really needed: Yes, control flow changed, block might get Bad. */
if (get_irg_dom_state(current_ir_graph) == dom_consistent)
set_irg_dom_inconsistent(current_ir_graph);
}
projects / libfirm / blobdiff