+/*
+ * 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.
+ */
+
/*
* Project: libFIRM
* File name: ir/opt/escape_ana.c
* Created: 03.11.2005
* CVS-ID: $Id$
* Copyright: (c) 1999-2005 Universität Karlsruhe
- * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
*/
-/** @file escape_ana.c
+/**
+ * @file escape_ana.c
*
- * escape analysis.
+ * A fast and simple Escape analysis.
*/
+#include "config.h"
-#ifdef HAVE_CONFIG_H
-# include "config.h"
-#endif
+#include "iroptimize.h"
#include "irgraph_t.h"
#include "irnode_t.h"
+#include "type_t.h"
+#include "irgwalk.h"
#include "irouts.h"
#include "analyze_irg_args.h"
#include "irgmod.h"
#include "ircons.h"
-#include "escape_ana.h"
+#include "irprintf.h"
+#include "debug.h"
/**
* walker environment
*/
typedef struct _walk_env {
- ir_node *found_allocs; /**< list of all found non-escaped allocs */
- ir_node *dead_allocs; /**< list of all found dead alloc */
- unsigned nr_changed; /**< number of changed allocs */
- unsigned nr_deads; /**< number of dead allocs */
+ ir_node *found_allocs; /**< list of all found non-escaped allocs */
+ ir_node *dead_allocs; /**< list of all found dead alloc */
+ check_alloc_entity_func callback; /**< callback that checks a given entity for allocation */
+ unsigned nr_removed; /**< number of removed allocs (placed of frame) */
+ unsigned nr_changed; /**< number of changed allocs (allocated on stack now) */
+ unsigned nr_deads; /**< number of dead allocs */
/* these fields are only used in the global escape analysis */
- ir_graph *irg; /**< the irg for this environment */
- struct _walk_env *next; /**< for linking environments */
+ ir_graph *irg; /**< the irg for this environment */
+ struct _walk_env *next; /**< for linking environments */
} walk_env_t;
+/** debug handle */
+DEBUG_ONLY(firm_dbg_module_t *dbgHandle;)
+
+/**
+ * checks whether a Raise leaves a method
+ */
+static int is_method_leaving_raise(ir_node *raise)
+{
+ int i;
+ ir_node *proj = NULL;
+ ir_node *n;
+
+ for (i = get_irn_n_outs(raise) - 1; i >= 0; --i) {
+ ir_node *succ = get_irn_out(raise, i);
+
+ /* there should be only one ProjX node */
+ if (get_Proj_proj(succ) == pn_Raise_X) {
+ proj = succ;
+ break;
+ }
+ }
+
+ if (! proj) {
+ /* Hmm: no ProjX from a Raise? This should be a verification
+ * error. For now we just assert and return.
+ */
+ assert(! "No ProjX after Raise found");
+ return 1;
+ }
+
+ if (get_irn_n_outs(proj) != 1) {
+ /* Hmm: more than one user of ProjX: This is a verification
+ * error.
+ */
+ assert(! "More than one user of ProjX");
+ return 1;
+ }
+
+ n = get_irn_out(proj, 0);
+ assert(is_Block(n) && "Argh: user of ProjX is no block");
+
+ if (n == get_irg_end_block(get_irn_irg(n)))
+ return 1;
+
+ /* ok, we get here so the raise will not leave the function */
+ return 0;
+}
+
+/**
+ * returns an Alloc node if the node adr Select
+ * from one
+ */
+static ir_node *is_depend_alloc(ir_node *adr) {
+ ir_node *alloc;
+
+ if (!is_Sel(adr))
+ return NULL;
+
+ /* should be a simple Sel */
+ if (get_Sel_n_indexs(adr) != 0)
+ return NULL;
+
+ alloc = skip_Proj(get_Sel_ptr(adr));
+ if (!is_Alloc(alloc))
+ return NULL;
+
+ /* hmm, we depend on this Alloc */
+ ir_printf("depend alloc %+F\n", alloc);
+
+ return NULL;
+}
+
/**
* determine if a value calculated by n "escape", ie
* is stored somewhere we could not track
*/
-static int do_escape(ir_node *n) {
+static int can_escape(ir_node *n) {
int i, j, k;
/* should always be pointer mode or we made some mistake */
for (i = get_irn_n_outs(n) - 1; i >= 0; --i) {
ir_node *succ = get_irn_out(n, i);
- ir_op *op = get_irn_op(succ);
- if (op == op_Store) {
+ switch (get_irn_opcode(succ)) {
+ case iro_Store:
if (get_Store_value(succ) == n) {
+ ir_node *adr = get_Store_ptr(succ);
+
+ /*
+ * if this Alloc depends on another one,
+ * we can enqueue it
+ */
+ if (is_depend_alloc(adr))
+ break;
+
/*
* We are storing n. As long as we do not further
* evaluate things, the pointer 'escape' here
*/
return 1;
}
- }
- else if (op == op_Conv) {
+ break;
+
+ case iro_Conv:
/*
* Should not happen, but if it does we leave the pointer
* path and do not track further
*/
return 1;
- }
- else if (op == op_Call) { /* most complicated case */
+
+ case iro_Call: { /* most complicated case */
ir_node *ptr = get_Call_ptr(succ);
- entity *ent;
+ ir_entity *ent;
- if (get_irn_op(ptr) == op_SymConst &&
- get_SymConst_kind(ptr) == symconst_addr_ent) {
+ if (is_SymConst_addr_ent(ptr)) {
ent = get_SymConst_entity(ptr);
/* we know the called entity */
- for (j = get_Call_n_params(succ); j >= 0; --j) {
+ for (j = get_Call_n_params(succ) - 1; j >= 0; --j) {
if (get_Call_param(succ, j) == n) {
/* n is the j'th param of the call */
if (get_method_param_access(ent, j) & ptr_access_store)
}
}
}
- else {
+ else if (is_Sel(ptr)) {
/* go through all possible callees */
for (k = get_Call_n_callees(succ) - 1; k >= 0; --k) {
ent = get_Call_callee(succ, k);
- for (j = get_Call_n_params(succ); j >= 0; --j) {
+ if (ent == unknown_entity) {
+ /* we don't know what will be called, a possible escape */
+ return 1;
+ }
+
+ for (j = get_Call_n_params(succ) - 1; j >= 0; --j) {
if (get_Call_param(succ, j) == n) {
/* n is the j'th param of the call */
if (get_method_param_access(ent, j) & ptr_access_store)
}
}
}
+ else /* we don't know want will called */
+ return 1;
+
+ break;
+ }
+
+ case iro_Return:
+ /* Bad: the allocate object is returned */
+ return 1;
+
+ case iro_Raise:
+ /* Hmm: if we do NOT leave the method, it's local */
+ if (is_method_leaving_raise(succ))
+ return 1;
+ break;
+
+ case iro_Tuple: {
+ ir_node *proj;
+
+ /* Bad: trace the tuple backwards */
+ for (j = get_irn_arity(succ) - 1; j >= 0; --j)
+ if (get_irn_n(succ, j) == n)
+ break;
+
+ assert(j >= 0);
+
+
+ for (k = get_irn_n_outs(succ); k >= 0; --k) {
+ proj = get_irn_out(succ, k);
+
+ if (get_Proj_proj(proj) == j) {
+ /* we found the right Proj */
+ succ = proj;
+ break;
+ }
+ }
+
+ /*
+ * If we haven't found the right Proj, succ is still
+ * the Tuple and the search will end here.
+ */
+ break;
+ }
+
+ default:
+ break;
+
}
if (! mode_is_reference(get_irn_mode(succ)))
continue;
- if (do_escape(succ))
+ if (can_escape(succ))
return 1;
}
return 0;
ir_node *adr;
walk_env_t *env = ctx;
- if (get_irn_op(alloc) != op_Alloc)
+ if (! is_Alloc(alloc))
return;
/* we searching only for heap allocations */
return;
adr = NULL;
- for (i = get_irn_n_outs(alloc); i >= 0; --i) {
+ for (i = get_irn_n_outs(alloc) - 1; i >= 0; --i) {
ir_node *proj = get_irn_out(alloc, i);
if (get_Proj_proj(proj) == pn_Alloc_res) {
return;
}
- if (! do_escape(adr)) {
+ if (! can_escape(adr)) {
set_irn_link(alloc, env->found_allocs);
env->found_allocs = alloc;
}
}
/**
- * do the necessary graph transformations
+ * walker: search for allocation Call nodes and follow the usages
+ */
+static void find_allocation_calls(ir_node *call, void *ctx)
+{
+ int i;
+ ir_node *adr;
+ ir_entity *ent;
+ walk_env_t *env = ctx;
+
+ if (! is_Call(call))
+ return;
+ adr = get_Call_ptr(call);
+ if (! is_SymConst_addr_ent(adr))
+ return;
+ ent = get_SymConst_entity(adr);
+ if (! env->callback(ent))
+ return;
+
+ adr = NULL;
+ for (i = get_irn_n_outs(call) - 1; i >= 0; --i) {
+ ir_node *res_proj = get_irn_out(call, i);
+
+ if (get_Proj_proj(res_proj) == pn_Call_T_result) {
+ for (i = get_irn_n_outs(res_proj) - 1; i >= 0; --i) {
+ ir_node *proj = get_irn_out(res_proj, i);
+
+ if (get_Proj_proj(proj) == 0) {
+ /* found first result */
+ adr = proj;
+ break;
+ }
+ }
+ break;
+ }
+ }
+
+ if (! adr) {
+ /*
+ * bad: no-one wants the result, should NOT happen but
+ * if it does we could delete it.
+ */
+ set_irn_link(call, env->dead_allocs);
+ env->dead_allocs = call;
+
+ return;
+ }
+
+ if (! can_escape(adr)) {
+ set_irn_link(call, env->found_allocs);
+ env->found_allocs = call;
+ }
+}
+
+/**
+ * Do the necessary graph transformations to transform
+ * Alloc nodes.
*/
static void transform_allocs(ir_graph *irg, walk_env_t *env)
{
- ir_node *alloc, *next, *mem, *sel;
- type *ftp;
- entity *ent;
- char name[32];
+ ir_node *alloc, *next, *mem, *sel, *size, *blk;
+ ir_type *ftp, *atp, *tp;
+ ir_entity *ent;
+ char name[128];
unsigned nr = 0;
dbg_info *dbg;
for (alloc = env->dead_allocs; alloc; alloc = next) {
next = get_irn_link(alloc);
+ DBG((dbgHandle, LEVEL_1, "%+F allocation of %+F unused, deleted.\n", irg, alloc));
+
mem = get_Alloc_mem(alloc);
+ blk = get_nodes_block(alloc);
turn_into_tuple(alloc, pn_Alloc_max);
set_Tuple_pred(alloc, pn_Alloc_M, mem);
+ set_Tuple_pred(alloc, pn_Alloc_X_regular, new_r_Jmp(irg, blk));
set_Tuple_pred(alloc, pn_Alloc_X_except, new_r_Bad(irg));
++env->nr_deads;
/* convert all non-escaped heap allocs into frame variables */
ftp = get_irg_frame_type(irg);
- for (alloc = env->dead_allocs; alloc; alloc = next) {
+ for (alloc = env->found_allocs; alloc; alloc = next) {
next = get_irn_link(alloc);
- dbg = get_irn_dbg_info(alloc);
+ size = get_Alloc_size(alloc);
+ atp = get_Alloc_type(alloc);
+
+ tp = NULL;
+ if (is_SymConst(size) && get_SymConst_kind(size) == symconst_type_size) {
+ /* if the size is a type size and the types matched */
+ assert(atp == get_SymConst_type(size));
+ tp = atp;
+ }
+ else if (is_Const(size)) {
+ tarval *tv = get_Const_tarval(size);
+
+ if (tv != tarval_bad && tarval_is_long(tv) &&
+ get_type_state(atp) == layout_fixed &&
+ (unsigned)get_tarval_long(tv) == get_type_size_bytes(atp)) {
+ /* a already lowered type size */
+ tp = atp;
+ }
+ }
- snprintf(name, sizeof(name), "_not_escaped_%u", nr++);
- ent = new_d_entity(ftp, new_id_from_str(name), get_Alloc_type(alloc), dbg);
+ if (tp && tp != firm_unknown_type) {
+ /* we could determine the type, so we could place it on the frame */
+ dbg = get_irn_dbg_info(alloc);
+ blk = get_nodes_block(alloc);
- sel = new_rd_simpleSel(dbg, irg, get_nodes_block(alloc),
- get_irg_no_mem(irg), get_irg_frame(irg), ent);
- mem = get_Alloc_mem(alloc);
+ DBG((dbgHandle, LEVEL_DEFAULT, "%+F allocation of %+F type %+F placed on frame\n", irg, alloc, tp));
- turn_into_tuple(alloc, pn_Alloc_max);
- set_Tuple_pred(alloc, pn_Alloc_M, mem);
- set_Tuple_pred(alloc, pn_Alloc_X_except, new_r_Bad(irg));
- set_Tuple_pred(alloc, pn_Alloc_res, sel);
+ snprintf(name, sizeof(name), "%s_NE_%u", get_entity_name(get_irg_entity(irg)), nr++);
+ name[sizeof(name) - 1] = '\0';
+ ent = new_d_entity(ftp, new_id_from_str(name), get_Alloc_type(alloc), dbg);
+
+ sel = new_rd_simpleSel(dbg, irg, get_nodes_block(alloc),
+ get_irg_no_mem(irg), get_irg_frame(irg), ent);
+ mem = get_Alloc_mem(alloc);
+
+ turn_into_tuple(alloc, pn_Alloc_max);
+ set_Tuple_pred(alloc, pn_Alloc_M, mem);
+ set_Tuple_pred(alloc, pn_Alloc_X_regular, new_r_Jmp(irg, blk));
+ set_Tuple_pred(alloc, pn_Alloc_X_except, new_r_Bad(irg));
+ set_Tuple_pred(alloc, pn_Alloc_res, sel);
+
+ ++env->nr_removed;
+ }
+ else {
+ /*
+ * We could not determine the type or it is variable size.
+ * At least, we could place it on the stack
+ */
+ DBG((dbgHandle, LEVEL_DEFAULT, "%+F allocation of %+F type %+F placed on stack\n", irg, alloc));
+ set_Alloc_where(alloc, stack_alloc);
- ++env->nr_changed;
+ ++env->nr_changed;
+ }
}
- if (env->nr_changed | env->nr_deads) {
+ /* if allocs were removed somehow */
+ if (env->nr_removed | env->nr_deads) {
set_irg_outs_inconsistent(irg);
- if (env->nr_deads)
- set_irg_dom_inconsistent(irg);
+ if (env->nr_deads) {
+ /* exception control flow might have been changed */
+ set_irg_doms_inconsistent(irg);
+ }
+ }
+}
+
+/**
+ * Do the necessary graph transformations to transform
+ * Call nodes.
+ */
+static void transform_alloc_calls(ir_graph *irg, walk_env_t *env)
+{
+ ir_node *call, *next, *mem, *blk;
+ ir_type *ftp;
+
+ /* kill all dead allocs */
+ for (call = env->dead_allocs; call; call = next) {
+ next = get_irn_link(call);
+
+ DBG((dbgHandle, LEVEL_1, "%+F allocation of %+F unused, deleted.\n", irg, call));
+
+ mem = get_Call_mem(call);
+ blk = get_nodes_block(call);
+ turn_into_tuple(call, pn_Call_max);
+ set_Tuple_pred(call, pn_Call_M_regular, mem);
+ set_Tuple_pred(call, pn_Call_X_regular, new_r_Jmp(irg, blk));
+ set_Tuple_pred(call, pn_Call_X_except, new_r_Bad(irg));
+ set_Tuple_pred(call, pn_Call_T_result, new_r_Bad(irg));
+ set_Tuple_pred(call, pn_Call_M_except, mem);
+ set_Tuple_pred(call, pn_Call_P_value_res_base, new_r_Bad(irg));
+
+ ++env->nr_deads;
+ }
+
+ /* convert all non-escaped heap allocs into frame variables */
+ ftp = get_irg_frame_type(irg);
+ for (call = env->found_allocs; call; call = next) {
+ next = get_irn_link(call);
}
}
+
/* Do simple and fast escape analysis for one graph. */
-void escape_enalysis_irg(ir_graph *irg)
+void escape_enalysis_irg(ir_graph *irg, check_alloc_entity_func callback)
{
walk_env_t env;
env.found_allocs = NULL;
env.dead_allocs = NULL;
+ env.callback = callback;
+ env.nr_removed = 0;
env.nr_changed = 0;
env.nr_deads = 0;
- irg_walk_graph(irg, NULL, find_allocations, &env);
-
- transform_allocs(irg, &env);
+ if (callback) {
+ /* search for Calls */
+ irg_walk_graph(irg, NULL, find_allocation_calls, &env);
+ transform_alloc_calls(irg, &env);
+ } else {
+ /* search for Alloc nodes */
+ irg_walk_graph(irg, NULL, find_allocations, &env);
+ transform_allocs(irg, &env);
+ }
}
/* Do simple and fast escape analysis for all graphs. */
-void escape_analysis(int run_scalar_replace)
+void escape_analysis(int run_scalar_replace, check_alloc_entity_func callback)
{
ir_graph *irg;
int i;
struct obstack obst;
walk_env_t *env, *elist;
+ (void) run_scalar_replace;
if (get_irp_callee_info_state() != irg_callee_info_consistent) {
assert(! "need callee info");
return;
}
+ FIRM_DBG_REGISTER(dbgHandle, "firm.opt.escape_ana");
+
/*
* We treat memory for speed: we first collect all info in a
* list of environments, than do the transformation.
env = obstack_alloc(&obst, sizeof(*env));
env->found_allocs = NULL;
env->dead_allocs = NULL;
+ env->callback = callback;
for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
irg = get_irp_irg(i);
- if (get_irg_outs_state(irg) != outs_consistent)
- compute_irg_outs(irg);
+ assure_irg_outs(irg);
- irg_walk_graph(irg, NULL, find_allocations, &env);
+ if (callback) {
+ /* search for Calls */
+ irg_walk_graph(irg, NULL, find_allocation_calls, env);
+ } else {
+ /* search for Alloc nodes */
+ irg_walk_graph(irg, NULL, find_allocations, env);
+ }
if (env->found_allocs || env->dead_allocs) {
- env->nr_changed = 0;
+ env->nr_removed = 0;
env->nr_deads = 0;
env->irg = irg;
env->next = elist;
env = obstack_alloc(&obst, sizeof(*env));
env->found_allocs = NULL;
env->dead_allocs = NULL;
+ env->callback = callback;
}
}
- for (env = elist; env; env = env->next) {
- transform_allocs(env->irg, env);
+ if (callback) {
+ for (env = elist; env; env = env->next) {
+ transform_alloc_calls(env->irg, env);
+ }
+ } else {
+ for (env = elist; env; env = env->next) {
+ transform_allocs(env->irg, env);
+ }
}
obstack_free(&obst, NULL);
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