/*
- * Project: libFIRM
- * File name: ir/opt/ldstopt.c
- * Purpose: load store optimizations
- * Author: Michael Beck
- * Created:
- * CVS-ID: $Id$
- * Copyright: (c) 1998-2007 Universität Karlsruhe
- * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
+ * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
+ *
+ * This file is part of libFirm.
+ *
+ * This file may be distributed and/or modified under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation and appearing in the file LICENSE.GPL included in the
+ * packaging of this file.
+ *
+ * Licensees holding valid libFirm Professional Edition licenses may use
+ * this file in accordance with the libFirm Commercial License.
+ * Agreement provided with the Software.
+ *
+ * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+ * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE.
+ */
+
+/**
+ * @file
+ * @brief Load/Store optimizations.
+ * @author Michael Beck
+ * @version $Id$
*/
#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 <string.h>
+#include "iroptimize.h"
#include "irnode_t.h"
#include "irgraph_t.h"
#include "irmode_t.h"
#include "irtools.h"
#include "opt_polymorphy.h"
#include "irmemory.h"
+#include "xmalloc.h"
+#include "irphase_t.h"
+#include "irgopt.h"
+#include "debug.h"
+
+/** The debug handle. */
+DEBUG_ONLY(static firm_dbg_module_t *dbg;)
#ifdef DO_CACHEOPT
#include "cacheopt/cachesim.h"
#undef IMAX
#define IMAX(a,b) ((a) > (b) ? (a) : (b))
-#define MAX_PROJ IMAX(pn_Load_max, pn_Store_max)
+#define MAX_PROJ IMAX(IMAX(pn_Load_max, pn_Store_max), pn_Call_max)
enum changes_t {
DF_CHANGED = 1, /**< data flow changed */
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 */
- unsigned flags; /**< flags */
unsigned visited; /**< visited counter for breaking loops */
} ldst_info_t;
/**
* get the Load/Store info of a node
*/
-static ldst_info_t *get_ldst_info(ir_node *node, walk_env_t *env) {
+static ldst_info_t *get_ldst_info(ir_node *node, struct obstack *obst) {
ldst_info_t *info = get_irn_link(node);
if (! info) {
- info = obstack_alloc(&env->obst, sizeof(*info));
+ info = obstack_alloc(obst, sizeof(*info));
memset(info, 0, sizeof(*info));
set_irn_link(node, info);
}
/**
* get the Block info of a node
*/
-static block_info_t *get_block_info(ir_node *node, walk_env_t *env) {
+static block_info_t *get_block_info(ir_node *node, struct obstack *obst) {
block_info_t *info = get_irn_link(node);
if (! info) {
- info = obstack_alloc(&env->obst, sizeof(*info));
+ info = obstack_alloc(obst, sizeof(*info));
memset(info, 0, sizeof(*info));
set_irn_link(node, info);
}
*/
static void collect_nodes(ir_node *node, void *env)
{
- ir_op *op = get_irn_op(node);
+ ir_opcode opcode = get_irn_opcode(node);
ir_node *pred, *blk, *pred_blk;
ldst_info_t *ldst_info;
walk_env_t *wenv = env;
- if (op == op_Proj) {
- ir_node *adr;
- ir_op *op;
+ if (opcode == iro_Proj) {
+ pred = get_Proj_pred(node);
+ opcode = get_irn_opcode(pred);
- pred = get_Proj_pred(node);
- op = get_irn_op(pred);
-
- if (op == op_Load) {
- ldst_info = get_ldst_info(pred, wenv);
+ if (opcode == iro_Load || opcode == iro_Store || opcode == iro_Call) {
+ ldst_info = get_ldst_info(pred, &wenv->obst);
wenv->changes |= update_projs(ldst_info, node);
- if ((ldst_info->flags & LDST_VISITED) == 0) {
- adr = get_Load_ptr(pred);
- 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) {
- ldst_info = get_ldst_info(pred, wenv);
-
- wenv->changes |= update_projs(ldst_info, node);
-
- if ((ldst_info->flags & LDST_VISITED) == 0) {
- adr = get_Store_ptr(pred);
- 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.
- */
+ * 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) {
set_nodes_block(node, pred_blk);
}
}
- } else if (op == op_Block) {
+ } else if (opcode == iro_Block) {
int i;
for (i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
- ir_node *pred_block;
+ ir_node *pred_block, *proj;
block_info_t *bl_info;
+ int is_exc = 0;
- pred = skip_Proj(get_Block_cfgpred(node, i));
+ pred = proj = get_Block_cfgpred(node, i);
+
+ if (is_Proj(proj)) {
+ pred = get_Proj_pred(proj);
+ is_exc = get_Proj_proj(proj) == pn_Generic_X_except;
+ }
/* ignore Bad predecessors, they will be removed later */
if (is_Bad(pred))
continue;
pred_block = get_nodes_block(pred);
- bl_info = get_block_info(pred_block, wenv);
+ bl_info = get_block_info(pred_block, &wenv->obst);
- if (is_fragile_op(pred))
+ if (is_fragile_op(pred) && is_exc)
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);
+ opcode = get_irn_opcode(pred);
+ if (is_exc && (opcode == iro_Load || opcode == iro_Store || opcode == iro_Call)) {
+ ldst_info = get_ldst_info(pred, &wenv->obst);
wenv->changes |= update_exc(ldst_info, node, i);
}
*/
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);
+ assert(is_Const(index));
return get_tarval_long(get_Const_tarval(index));
} /* get_Sel_array_index_long */
/* a Load which value is neither used nor exception checked, remove it */
exchange(info->projs[pn_Load_M], mem);
- exchange(load, new_Bad());
+ if (info->projs[pn_Load_X_regular])
+ exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load)));
+ kill_node(load);
reduce_adr_usage(ptr);
}
} /* handle_load_update */
} /* can_use_stored_value */
/**
- * Follow the memory chain as long as there are only Loads
- * and alias free Stores and try to replace current Load or Store
- * by a previous ones.
+ * Check whether a Call is at least pure, ie. does only read memory.
+ */
+static unsigned is_Call_pure(ir_node *call) {
+ ir_type *call_tp = get_Call_type(call);
+ unsigned prop = get_method_additional_properties(call_tp);
+
+ /* check first the call type */
+ if ((prop & (mtp_property_const|mtp_property_pure)) == 0) {
+ /* try the called entity */
+ ir_node *ptr = get_Call_ptr(call);
+
+ if (is_Global(ptr)) {
+ ir_entity *ent = get_Global_entity(ptr);
+
+ prop = get_entity_additional_properties(ent);
+ }
+ }
+ return (prop & (mtp_property_const|mtp_property_pure)) != 0;
+} /* is_Call_pure */
+
+/**
+ * Follow the memory chain as long as there are only Loads,
+ * alias free Stores, and constant Calls and try to replace the
+ * current Load by a previous ones.
* 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.
* This is only true in strong typed languages, not in C were the following
* is possible a = *(ir_type1 *)p; b = *(ir_type2 *)p ...
*/
- if (get_irn_op(pred) == op_Store && get_Store_ptr(pred) == ptr &&
+ if (is_Store(pred) && get_Store_ptr(pred) == ptr &&
can_use_stored_value(get_irn_mode(get_Store_value(pred)), load_mode)) {
/*
* 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
+ * OR they are in the same MacroBlock. In the latter case the Load cannot
* throw an exception when the previous Store was quiet.
*
* 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 :-(
+ * the load MacroBlock :-(
* 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)) {
+ if ((pred_info->projs[pn_Store_X_except] == NULL && info->projs[pn_Load_X_except] == NULL) ||
+ get_nodes_MacroBlock(load) == get_nodes_MacroBlock(pred)) {
ir_node *value = get_Store_value(pred);
DBG_OPT_RAW(load, value);
exchange( info->projs[pn_Load_X_except], new_Bad());
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)));
+ res |= CF_CHANGED;
+ }
if (info->projs[pn_Load_res])
exchange(info->projs[pn_Load_res], value);
- exchange(load, new_Bad());
+ kill_node(load);
reduce_adr_usage(ptr);
return res | DF_CHANGED;
}
- } else if (get_irn_op(pred) == op_Load && get_Load_ptr(pred) == ptr &&
+ } else if (is_Load(pred) && get_Load_ptr(pred) == ptr &&
can_use_stored_value(get_Load_mode(pred), load_mode)) {
/*
* a Load after a Load -- a read after read.
* We may remove the second Load, if it does not have an exception handler
- * OR they are in the same block. In the later case the Load cannot
+ * OR they are in the same MacroBlock. 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 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)) {
+ if (info->projs[pn_Load_X_except] == NULL || get_nodes_MacroBlock(load) == get_nodes_MacroBlock(pred)) {
+ ir_node *value;
+
DBG_OPT_RAR(load, pred);
- if (pred_info->projs[pn_Load_res]) {
- ir_node *value = pred_info->projs[pn_Load_res];
+ /* the result is used */
+ 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);
+ }
+ 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);
}
- /* we need a data proj from the previous load for this optimization */
- 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);
- } else {
- 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
- properly!!! */
- exchange(info->projs[pn_Load_M], mem);
- }
+ exchange(info->projs[pn_Load_res], value);
}
+ if (info->projs[pn_Load_M])
+ exchange(info->projs[pn_Load_M], mem);
+
/* no exception */
if (info->projs[pn_Load_X_except]) {
exchange(info->projs[pn_Load_X_except], new_Bad());
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)));
+ res |= CF_CHANGED;
+ }
- exchange(load, new_Bad());
+ kill_node(load);
reduce_adr_usage(ptr);
return res |= DF_CHANGED;
}
}
- if (get_irn_op(pred) == op_Store) {
- /* check if we can pass thru this store */
+ if (is_Store(pred)) {
+ /* check if we can pass through this store */
ir_alias_relation rel = get_alias_relation(
current_ir_graph,
get_Store_ptr(pred),
get_irn_mode(get_Store_value(pred)),
ptr, load_mode);
/* if the might be an alias, we cannot pass this Store */
- if (rel != no_alias)
+ if (rel != ir_no_alias)
break;
pred = skip_Proj(get_Store_mem(pred));
- } else if (get_irn_op(pred) == op_Load) {
+ } else if (is_Load(pred)) {
pred = skip_Proj(get_Load_mem(pred));
+ } else if (is_Call(pred)) {
+ if (is_Call_pure(pred)) {
+ /* The called graph is at least pure, so there are no Store's
+ in it. We can handle it like a Load and skip it. */
+ pred = skip_Proj(get_Call_mem(pred));
+ } else {
+ /* there might be Store's in the graph, stop here */
+ break;
+ }
} else {
/* follow only Load chains */
break;
MARK_NODE(pred_info);
}
- if (get_irn_op(pred) == op_Sync) {
+ if (is_Sync(pred)) {
int i;
/* handle all Sync predecessors */
for (i = get_Sync_n_preds(pred) - 1; i >= 0; --i) {
res |= follow_Mem_chain(load, skip_Proj(get_Sync_pred(pred, i)));
if (res)
- break;
+ return res;
}
}
ir_node *mem = get_Sel_mem(ptr);
/* FIXME: works with the current FE, but better use the base */
- if (get_irn_op(skip_Proj(mem)) == op_Alloc) {
+ if (is_Alloc(skip_Proj(mem))) {
/* ok, check the types */
ir_entity *ent = get_Sel_entity(ptr);
ir_type *s_type = get_entity_type(ent);
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)));
+ info->projs[pn_Load_X_regular] = NULL;
res |= CF_CHANGED;
}
}
- } 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))) {
+ } else if (is_Alloc(skip_Proj(skip_Cast(ptr)))) {
/* 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;
+ exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load)));
+ info->projs[pn_Load_X_regular] = NULL;
res |= CF_CHANGED;
}
}
/* a Load which value is neither used nor exception checked, remove it */
exchange(info->projs[pn_Load_M], mem);
- exchange(load, new_Bad());
+ 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)));
+ res |= CF_CHANGED;
+ }
+ kill_node(load);
reduce_adr_usage(ptr);
return res | DF_CHANGED;
}
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 (info->projs[pn_Load_X_regular]) {
+ exchange(info->projs[pn_Load_X_regular], new_r_Jmp(current_ir_graph, get_nodes_block(load)));
+ info->projs[pn_Load_X_regular] = NULL;
+ res |= CF_CHANGED;
}
if (info->projs[pn_Load_res])
exchange(info->projs[pn_Load_res], new_node);
- exchange(load, new_Bad());
+ kill_node(load);
reduce_adr_usage(ptr);
return res | DF_CHANGED;
}
info->projs[pn_Load_X_except] = NULL;
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)));
+ info->projs[pn_Load_X_regular] = 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. */
- /* 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]) {
- exchange(info->projs[pn_Load_M], mem);
- res |= DF_CHANGED;
- }
- /* no result :-) */
- if (info->projs[pn_Load_res]) {
- if (is_atomic_entity(ent)) {
- ir_node *c = copy_const_value(get_irn_dbg_info(load), get_atomic_ent_value(ent));
-
- DBG_OPT_RC(load, c);
- exchange(info->projs[pn_Load_res], c);
- res |= DF_CHANGED;
- }
- }
- exchange(load, new_Bad());
- reduce_adr_usage(ptr);
- return 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) {
- ir_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);
-
- /* printf(" cons: "); DDMN(c); */
-
+ if (variability_constant == get_entity_variability(ent)) {
+ if (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]) {
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_irn_dbg_info(load), c));
- res |= DF_CHANGED;
+ if (is_atomic_entity(ent)) {
+ ir_node *c = copy_const_value(get_irn_dbg_info(load), get_atomic_ent_value(ent));
+
+ DBG_OPT_RC(load, c);
+ exchange(info->projs[pn_Load_res], c);
+ res |= DF_CHANGED;
+ }
}
- exchange(load, new_Bad());
+ kill_node(load);
reduce_adr_usage(ptr);
return res;
} 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);
- */
+ compound_graph_path *path = get_accessed_path(ptr);
+
+ if (path && !ent->has_initializer) {
+ 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) {
+ ir_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);
+
+ /* 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(get_irn_dbg_info(load), c));
+ res |= DF_CHANGED;
+ }
+ kill_node(load);
+ reduce_adr_usage(ptr);
+ return res;
+ } 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);
+ */
+ }
}
}
}
ir_node *value = get_Store_value(store);
ir_mode *mode = get_irn_mode(value);
ir_node *block = get_nodes_block(store);
+ ir_node *mblk = get_Block_MacroBlock(block);
for (pred = curr; pred != store;) {
ldst_info_t *pred_info = get_irn_link(pred);
* However, if the mode that is written have a bigger or equal size the the old
* one, the old value is completely overwritten and can be killed ...
*/
- if (get_irn_op(pred) == op_Store && get_Store_ptr(pred) == ptr &&
- get_nodes_block(pred) == block &&
+ if (is_Store(pred) && get_Store_ptr(pred) == ptr &&
+ get_nodes_MacroBlock(pred) == mblk &&
is_completely_overwritten(get_irn_mode(get_Store_value(pred)), mode)) {
/*
- * a Store after a Store in the same block -- a write after write.
+ * a Store after a Store in the same MacroBlock -- a write after write.
* We may remove the first Store, if it does not have an exception handler.
*
* TODO: What, if both have the same exception handler ???
*/
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) );
- exchange(pred, new_Bad());
+ exchange(pred_info->projs[pn_Store_M], get_Store_mem(pred));
+ kill_node(pred);
reduce_adr_usage(ptr);
return DF_CHANGED;
}
- } else if (get_irn_op(pred) == op_Load && get_Load_ptr(pred) == ptr &&
+ } else if (is_Load(pred) && get_Load_ptr(pred) == ptr &&
value == pred_info->projs[pn_Load_res]) {
/*
- * a Store of a value after a Load -- a write after read.
- * We may remove the second Store, if it does not have an exception handler.
+ * a Store of a value just loaded from the same address
+ * -- a write after read.
+ * We may remove the Store, if it does not have an exception
+ * handler.
*/
if (! info->projs[pn_Store_X_except]) {
DBG_OPT_WAR(store, pred);
- exchange( info->projs[pn_Store_M], mem );
- exchange(store, new_Bad());
+ exchange(info->projs[pn_Store_M], mem);
+ kill_node(store);
reduce_adr_usage(ptr);
return DF_CHANGED;
}
}
- if (get_irn_op(pred) == op_Store) {
+ if (is_Store(pred)) {
/* check if we can pass thru this store */
ir_alias_relation rel = get_alias_relation(
current_ir_graph,
get_irn_mode(get_Store_value(pred)),
ptr, mode);
/* if the might be an alias, we cannot pass this Store */
- if (rel != no_alias)
+ if (rel != ir_no_alias)
break;
pred = skip_Proj(get_Store_mem(pred));
} else if (get_irn_op(pred) == op_Load) {
+ ir_alias_relation rel = get_alias_relation(
+ current_ir_graph, get_Load_ptr(pred), get_Load_mode(pred),
+ ptr, mode);
+ if (rel != ir_no_alias)
+ break;
+
pred = skip_Proj(get_Load_mem(pred));
} else {
/* follow only Load chains */
MARK_NODE(pred_info);
}
- if (get_irn_op(pred) == op_Sync) {
+ if (is_Sync(pred)) {
int i;
/* handle all Sync predecessors */
/* follow the memory chain as long as there are only Loads */
INC_MASTER();
+
return follow_Mem_chain_for_Store(store, skip_Proj(mem));
} /* optimize_store */
int i, n;
ir_node *store, *old_store, *ptr, *block, *phi_block, *phiM, *phiD, *exc, *projM;
ir_mode *mode;
- ir_node **inM, **inD, **stores;
+ ir_node **inM, **inD, **projMs;
int *idx;
dbg_info *db = NULL;
ldst_info_t *info;
if (n <= 0)
return 0;
- store = skip_Proj(get_Phi_pred(phi, 0));
+ /* must be only one user */
+ projM = get_Phi_pred(phi, 0);
+ if (get_irn_n_edges(projM) != 1)
+ return 0;
+
+ store = skip_Proj(projM);
old_store = store;
if (get_irn_op(store) != op_Store)
return 0;
return 0;
phi_block = get_nodes_block(phi);
- if (! block_postdominates(phi_block, block))
+ if (! block_strictly_postdominates(phi_block, block))
return 0;
/* this is the address of the store */
exc = info->exc_block;
for (i = 1; i < n; ++i) {
- ir_node *pred = skip_Proj(get_Phi_pred(phi, i));
+ ir_node *pred = get_Phi_pred(phi, i);
+
+ if (get_irn_n_edges(pred) != 1)
+ return 0;
- if (get_irn_op(pred) != op_Store)
+ pred = skip_Proj(pred);
+ if (!is_Store(pred))
return 0;
if (ptr != get_Store_ptr(pred) || mode != get_irn_mode(get_Store_value(pred)))
* Is only allowed if the predecessor blocks have only one successor.
*/
- NEW_ARR_A(ir_node *, stores, n);
+ NEW_ARR_A(ir_node *, projMs, n);
NEW_ARR_A(ir_node *, inM, n);
NEW_ARR_A(ir_node *, inD, n);
NEW_ARR_A(int, idx, n);
first because we otherwise may loose a store when exchanging its
memory Proj.
*/
- for (i = 0; i < n; ++i)
- stores[i] = skip_Proj(get_Phi_pred(phi, i));
-
- /* Prepare: Skip the memory Proj: we need this in the case some stores
- are cascaded.
- Beware: One Store might be included more than once in the stores[]
- list, so we must prevent to do the exchange more than once.
- */
- for (i = 0; i < n; ++i) {
- ir_node *store = stores[i];
- ir_node *proj_m;
-
- info = get_irn_link(store);
- proj_m = info->projs[pn_Store_M];
+ for (i = n - 1; i >= 0; --i) {
+ ir_node *store;
- if (is_Proj(proj_m) && get_Proj_pred(proj_m) == store)
- exchange(proj_m, get_Store_mem(store));
- }
+ projMs[i] = get_Phi_pred(phi, i);
+ assert(is_Proj(projMs[i]));
- /* first step: collect all inputs */
- for (i = 0; i < n; ++i) {
- ir_node *store = stores[i];
- info = get_irn_link(store);
+ store = get_Proj_pred(projMs[i]);
+ info = get_irn_link(store);
inM[i] = get_Store_mem(store);
inD[i] = get_Store_value(store);
/* third step: create a new data Phi */
phiD = new_rd_Phi(get_irn_dbg_info(phi), current_ir_graph, block, n, inD, mode);
+ /* rewire memory and kill the node */
+ for (i = n - 1; i >= 0; --i) {
+ ir_node *proj = projMs[i];
+
+ if(is_Proj(proj)) {
+ ir_node *store = get_Proj_pred(proj);
+ exchange(proj, inM[i]);
+ kill_node(store);
+ }
+ }
+
/* fourth step: create the Store */
store = new_rd_Store(db, current_ir_graph, block, phiM, ptr, phiD);
#ifdef DO_CACHEOPT
projM = new_rd_Proj(NULL, current_ir_graph, block, store, mode_M, pn_Store_M);
- info = get_ldst_info(store, wenv);
+ info = get_ldst_info(store, &wenv->obst);
info->projs[pn_Store_M] = projM;
/* fifths step: repair exception flow */
case iro_Phi:
wenv->changes |= optimize_phi(n, wenv);
+ break;
default:
;
}
} /* do_load_store_optimize */
+/** A scc. */
+typedef struct scc {
+ ir_node *head; /**< the head of the list */
+} scc;
+
+/** A node entry. */
+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 */
+ unsigned POnum; /**< the post order number for blocks */
+} node_entry;
+
+/** A loop entry. */
+typedef struct loop_env {
+ ir_phase ph; /**< the phase object */
+ ir_node **stack; /**< the node stack */
+ int tos; /**< tos index */
+ unsigned nextDFSnum; /**< the current DFS number */
+ unsigned POnum; /**< current post order number */
+
+ unsigned changes; /**< a bitmask of graph changes */
+} loop_env;
+
+/**
+* Gets the node_entry of a node
+*/
+static node_entry *get_irn_ne(ir_node *irn, loop_env *env) {
+ ir_phase *ph = &env->ph;
+ node_entry *e = phase_get_irn_data(&env->ph, irn);
+
+ if (! e) {
+ e = phase_alloc(ph, sizeof(*e));
+ memset(e, 0, sizeof(*e));
+ phase_set_irn_data(ph, irn, e);
+ }
+ return e;
+} /* get_irn_ne */
+
+/**
+ * Push a node onto the stack.
+ *
+ * @param env the loop environment
+ * @param n the node to push
+ */
+static void push(loop_env *env, ir_node *n) {
+ node_entry *e;
+
+ if (env->tos == ARR_LEN(env->stack)) {
+ int nlen = ARR_LEN(env->stack) * 2;
+ ARR_RESIZE(ir_node *, env->stack, nlen);
+ }
+ env->stack[env->tos++] = n;
+ e = get_irn_ne(n, env);
+ e->in_stack = 1;
+} /* push */
+
+/**
+ * pop a node from the stack
+ *
+ * @param env the loop environment
+ *
+ * @return The topmost node
+ */
+static ir_node *pop(loop_env *env) {
+ ir_node *n = env->stack[--env->tos];
+ node_entry *e = get_irn_ne(n, env);
+
+ e->in_stack = 0;
+ return n;
+} /* pop */
+
+/**
+ * Check if irn is a region constant.
+ * The block or irn must strictly dominate the header block.
+ *
+ * @param irn the node to check
+ * @param header_block the header block of the induction variable
+ */
+static int is_rc(ir_node *irn, ir_node *header_block) {
+ ir_node *block = get_nodes_block(irn);
+
+ return (block != header_block) && block_dominates(block, header_block);
+} /* is_rc */
+
+typedef struct phi_entry phi_entry;
+struct phi_entry {
+ ir_node *phi; /**< A phi with a region const memory. */
+ int pos; /**< The position of the region const memory */
+ ir_node *load; /**< the newly created load for this phi */
+ phi_entry *next;
+};
+
+/**
+ * Move loops out of loops if possible.
+ *
+ * @param pscc the loop described by an SCC
+ * @param env the loop environment
+ */
+static void move_loads_out_of_loops(scc *pscc, loop_env *env) {
+ ir_node *phi, *load, *next, *other, *next_other;
+ ir_entity *ent;
+ int j;
+ phi_entry *phi_list = NULL;
+
+ /* collect all outer memories */
+ for (phi = pscc->head; phi != NULL; phi = next) {
+ node_entry *ne = get_irn_ne(phi, env);
+ next = ne->next;
+
+ /* check all memory Phi's */
+ if (! is_Phi(phi))
+ continue;
+
+ assert(get_irn_mode(phi) == mode_M && "DFS geturn non-memory Phi");
+
+ for (j = get_irn_arity(phi) - 1; j >= 0; --j) {
+ ir_node *pred = get_irn_n(phi, j);
+ node_entry *pe = get_irn_ne(pred, env);
+
+ if (pe->pscc != ne->pscc) {
+ /* not in the same SCC, is region const */
+ phi_entry *pe = phase_alloc(&env->ph, sizeof(*pe));
+
+ pe->phi = phi;
+ pe->pos = j;
+ pe->next = phi_list;
+ phi_list = pe;
+ }
+ }
+ }
+ /* no Phis no fun */
+ assert(phi_list != NULL && "DFS found a loop without Phi");
+
+ for (load = pscc->head; load; load = next) {
+ ir_mode *load_mode;
+ node_entry *ne = get_irn_ne(load, env);
+ next = ne->next;
+
+ if (is_Load(load)) {
+ ldst_info_t *info = get_irn_link(load);
+ ir_node *ptr = get_Load_ptr(load);
+
+ /* for now, we cannot handle Loads with exceptions */
+ 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) */
+ if (! is_Global(ptr))
+ continue;
+ 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);
+ next_other = ne->next;
+
+ if (is_Store(other)) {
+ ir_alias_relation rel = get_alias_relation(
+ current_ir_graph,
+ get_Store_ptr(other),
+ get_irn_mode(get_Store_value(other)),
+ ptr, load_mode);
+ /* if the might be an alias, we cannot pass this Store */
+ if (rel != ir_no_alias)
+ break;
+ }
+ /* only 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));
+
+ db = get_irn_dbg_info(load);
+ for (pe = phi_list; pe != NULL; pe = pe->next) {
+ int pos = pe->pos;
+ ir_node *phi = pe->phi;
+ 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);
+ 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);
+ 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));
+ }
+
+ /* now kill the old Load */
+ exchange(info->projs[pn_Load_M], get_Load_mem(load));
+ exchange(info->projs[pn_Load_res], ninfo->projs[pn_Load_res]);
+
+ env->changes |= DF_CHANGED;
+ }
+ }
+ }
+} /* move_loads_out_of_loops */
+
+/**
+ * Process a loop SCC.
+ *
+ * @param pscc the SCC
+ * @param env the loop environment
+ */
+static void process_loop(scc *pscc, loop_env *env) {
+ ir_node *irn, *next, *header = NULL;
+ node_entry *b, *h = NULL;
+ int j, only_phi, num_outside, process = 0;
+ ir_node *out_rc;
+
+ /* find the header block for this scc */
+ for (irn = pscc->head; irn; irn = next) {
+ node_entry *e = get_irn_ne(irn, env);
+ ir_node *block = get_nodes_block(irn);
+
+ next = e->next;
+ b = get_irn_ne(block, env);
+
+ if (header) {
+ if (h->POnum < b->POnum) {
+ header = block;
+ h = b;
+ }
+ }
+ else {
+ header = block;
+ h = b;
+ }
+ }
+
+ /* check if this scc contains only Phi, Loads or Stores nodes */
+ only_phi = 1;
+ num_outside = 0;
+ out_rc = NULL;
+ for (irn = pscc->head; irn; irn = next) {
+ node_entry *e = get_irn_ne(irn, env);
+
+ next = e->next;
+ switch (get_irn_opcode(irn)) {
+ case iro_Call:
+ if (is_Call_pure(irn)) {
+ /* pure calls can be treated like loads */
+ only_phi = 0;
+ break;
+ }
+ /* non-pure calls must be handle like may-alias Stores */
+ goto fail;
+ case iro_CopyB:
+ /* cannot handle CopyB yet */
+ goto fail;
+ case iro_Load:
+ process = 1;
+ if (get_Load_volatility(irn) == volatility_is_volatile) {
+ /* cannot handle loops with volatile Loads */
+ goto fail;
+ }
+ only_phi = 0;
+ break;
+ case iro_Store:
+ if (get_Store_volatility(irn) == volatility_is_volatile) {
+ /* cannot handle loops with volatile Stores */
+ goto fail;
+ }
+ only_phi = 0;
+ break;
+ default:
+ only_phi = 0;
+ break;
+ case iro_Phi:
+ for (j = get_irn_arity(irn) - 1; j >= 0; --j) {
+ ir_node *pred = get_irn_n(irn, j);
+ node_entry *pe = get_irn_ne(pred, env);
+
+ if (pe->pscc != e->pscc) {
+ /* not in the same SCC, must be a region const */
+ if (! is_rc(pred, header)) {
+ /* not a memory loop */
+ goto fail;
+ }
+ if (! out_rc) {
+ out_rc = pred;
+ ++num_outside;
+ } else if (out_rc != pred) {
+ ++num_outside;
+ }
+ }
+ }
+ break;
+ }
+ }
+ if (! process)
+ goto fail;
+
+ /* found a memory loop */
+ DB((dbg, LEVEL_2, " Found a memory loop:\n "));
+ if (only_phi && num_outside == 1) {
+ /* a phi cycle with only one real predecessor can be collapsed */
+ DB((dbg, LEVEL_2, " Found an USELESS Phi cycle:\n "));
+
+ 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 */
+ 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"));
+
+ move_loads_out_of_loops(pscc, env);
+
+fail:
+ ;
+} /* process_loop */
+
+/**
+ * Process a SCC.
+ *
+ * @param pscc the SCC
+ * @param env the loop environment
+ */
+static void process_scc(scc *pscc, loop_env *env) {
+ ir_node *head = pscc->head;
+ node_entry *e = get_irn_ne(head, env);
+
+#ifdef DEBUG_libfirm
+ {
+ ir_node *irn, *next;
+
+ DB((dbg, LEVEL_4, " SCC at %p:\n ", pscc));
+ for (irn = pscc->head; irn; irn = next) {
+ node_entry *e = get_irn_ne(irn, env);
+
+ next = e->next;
+
+ DB((dbg, LEVEL_4, " %+F,", irn));
+ }
+ DB((dbg, LEVEL_4, "\n"));
+ }
+#endif
+
+ if (e->next != NULL) {
+ /* this SCC has more than one member */
+ process_loop(pscc, env);
+ }
+} /* process_scc */
+
+/**
+ * Do Tarjan's SCC algorithm and drive load/store optimization.
+ *
+ * @param irn start at this node
+ * @param env the loop environment
+ */
+static void dfs(ir_node *irn, loop_env *env)
+{
+ int i, n;
+ node_entry *node = get_irn_ne(irn, env);
+
+ mark_irn_visited(irn);
+
+ node->DFSnum = env->nextDFSnum++;
+ node->low = node->DFSnum;
+ push(env, irn);
+
+ /* handle preds */
+ if (is_Phi(irn) || is_Sync(irn)) {
+ n = get_irn_arity(irn);
+ for (i = 0; i < n; ++i) {
+ ir_node *pred = get_irn_n(irn, i);
+ node_entry *o = get_irn_ne(pred, env);
+
+ if (irn_not_visited(pred)) {
+ dfs(pred, env);
+ node->low = MIN(node->low, o->low);
+ }
+ if (o->DFSnum < node->DFSnum && o->in_stack)
+ node->low = MIN(o->DFSnum, node->low);
+ }
+ } else if (is_fragile_op(irn)) {
+ ir_node *pred = get_fragile_op_mem(irn);
+ node_entry *o = get_irn_ne(pred, env);
+
+ if (irn_not_visited(pred)) {
+ dfs(pred, env);
+ node->low = MIN(node->low, o->low);
+ }
+ if (o->DFSnum < node->DFSnum && o->in_stack)
+ node->low = MIN(o->DFSnum, node->low);
+ } else if (is_Proj(irn)) {
+ ir_node *pred = get_Proj_pred(irn);
+ node_entry *o = get_irn_ne(pred, env);
+
+ if (irn_not_visited(pred)) {
+ dfs(pred, env);
+ node->low = MIN(node->low, o->low);
+ }
+ if (o->DFSnum < node->DFSnum && o->in_stack)
+ node->low = MIN(o->DFSnum, node->low);
+ }
+ else {
+ /* IGNORE predecessors */
+ }
+
+ if (node->low == node->DFSnum) {
+ scc *pscc = phase_alloc(&env->ph, sizeof(*pscc));
+ ir_node *x;
+
+ pscc->head = NULL;
+ do {
+ node_entry *e;
+
+ x = pop(env);
+ e = get_irn_ne(x, env);
+ e->pscc = pscc;
+ e->next = pscc->head;
+ pscc->head = x;
+ } while (x != irn);
+
+ process_scc(pscc, env);
+ }
+} /* dfs */
+
+/**
+ * Do the DFS on the memory edges a graph.
+ *
+ * @param irg the graph to process
+ * @param env the loop environment
+ */
+static void do_dfs(ir_graph *irg, loop_env *env) {
+ ir_graph *rem = current_ir_graph;
+ ir_node *endblk, *end;
+ int i;
+
+ current_ir_graph = irg;
+ inc_irg_visited(irg);
+
+ /* visit all memory nodes */
+ endblk = get_irg_end_block(irg);
+ for (i = get_Block_n_cfgpreds(endblk) - 1; i >= 0; --i) {
+ ir_node *pred = get_Block_cfgpred(endblk, i);
+
+ pred = skip_Proj(pred);
+ if (is_Return(pred))
+ dfs(get_Return_mem(pred), env);
+ else if (is_Raise(pred))
+ dfs(get_Raise_mem(pred), env);
+ else if (is_fragile_op(pred))
+ dfs(get_fragile_op_mem(pred), env);
+ else {
+ assert(0 && "Unknown EndBlock predecessor");
+ }
+ }
+
+ /* visit the keep-alives */
+ end = get_irg_end(irg);
+ 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))
+ dfs(ka, env);
+ }
+ current_ir_graph = rem;
+} /* do_dfs */
+
+/**
+ * Initialize new phase data. We do this always explicit, so return NULL here
+ */
+static void *init_loop_data(ir_phase *ph, const ir_node *irn, void *data) {
+ (void)ph;
+ (void)irn;
+ (void)data;
+ return NULL;
+} /* init_loop_data */
+
+/**
+ * Optimize Loads/Stores in loops.
+ *
+ * @param irg the graph
+ */
+static int optimize_loops(ir_graph *irg) {
+ loop_env env;
+
+ env.stack = NEW_ARR_F(ir_node *, 128);
+ env.tos = 0;
+ env.nextDFSnum = 0;
+ env.POnum = 0;
+ env.changes = 0;
+ phase_init(&env.ph, "ldstopt", irg, PHASE_DEFAULT_GROWTH, init_loop_data, NULL);
+
+ /* calculate the SCC's and drive loop optimization. */
+ do_dfs(irg, &env);
+
+ DEL_ARR_F(env.stack);
+ phase_free(&env.ph);
+
+ return env.changes;
+} /* optimize_loops */
+
/*
* do the load store optimization
*/
void optimize_load_store(ir_graph *irg) {
walk_env_t env;
+ FIRM_DBG_REGISTER(dbg, "firm.opt.ldstopt");
+
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;
+ /* we need landing pads */
+ remove_critical_cf_edges(irg);
edges_assure(irg);
/* now we have collected enough information, optimize */
irg_walk_graph(irg, NULL, do_load_store_optimize, &env);
+ env.changes |= optimize_loops(irg);
+
obstack_free(&env.obst, NULL);
/* Handle graph state */
if (env.changes) {
- if (get_irg_outs_state(irg) == outs_consistent)
- set_irg_outs_inconsistent(irg);
+ set_irg_outs_inconsistent(irg);
}
if (env.changes & CF_CHANGED) {
projects / libfirm / blobdiff