/*
- * Project: libFIRM
- * File name: ir/opt/funccall.c
- * Purpose: optimization of function calls
- * Author: Michael Beck
- * Created:
- * CVS-ID: $Id$
- * Copyright: (c) 1998-2004 Universit�t 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 Optimization of function calls.
+ * @author Michael Beck
+ * @version $Id$
*/
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <adt/raw_bitset.h>
+
+#include "funccall_t.h"
+
#include "irnode_t.h"
#include "irgraph_t.h"
#include "irgmod.h"
#include "dbginfo_t.h"
#include "irflag_t.h"
#include "ircons.h"
-#include "funccall.h"
#include "irhooks.h"
+#include "debug.h"
+
+DEBUG_ONLY(static firm_dbg_module_t *dbg;)
/**
- * The walker environment for rem_mem_from_const_fkt_calls
+ * The walker environment for updating function calls.
*/
typedef struct _env_t {
- int changed; /**< flag, is set if a graph was changed */
- int n_calls_removed_SymConst;
- int n_calls_removed_Sel;
+ unsigned n_calls_SymConst;
+ unsigned n_calls_Sel;
+ ir_node *const_call_list; /**< The list of all const function calls that will be changed. */
+ ir_node *pure_call_list; /**< The list of all pure function calls that will be changed. */
+ ir_node *nothrow_call_list; /**< The list of all nothrow function calls that will be changed. */
+ ir_node *proj_list; /**< The list of all potential Proj nodes that must be fixed. */
} env_t;
+/** If non-null, evaluates entities for being a heap alloc. */
+static check_alloc_entity_func is_alloc_entity = NULL;
+
+/** Ready IRG's are marked in the ready set. */
+static unsigned *ready_set;
+
+/** IRG's that are in progress are marked here. */
+static unsigned *busy_set;
+
+/**
+ * We misuse the mtp_property_inherited flag as temporary here.
+ * The is ok, as we cannot set or get it anyway using the
+ * get_addtional_properties API.
+ */
+#define mtp_temporary mtp_property_inherited
+
/**
- * remove memory from const function calls by rerouting
- * it's ProjM and connection the call with a NoMem node.
+ * Walker: Collect all calls to const and pure functions
+ * to lists. Collect all Proj(Call) nodes into a Proj list.
+ */
+static void collect_const_and_pure_calls(ir_node *node, void *env) {
+ env_t *ctx = env;
+ ir_node *call, *ptr;
+ ir_entity *ent;
+ unsigned prop;
+
+ if (is_Call(node)) {
+ call = node;
+
+ /* set the link to NULL for all non-const/pure calls */
+ set_irn_link(call, NULL);
+ ptr = get_Call_ptr(call);
+ if (is_SymConst_addr_ent(ptr)) {
+ ent = get_SymConst_entity(ptr);
+
+ prop = get_entity_additional_properties(ent);
+ if ((prop & (mtp_property_const|mtp_property_pure)) == 0)
+ return;
+ ++ctx->n_calls_SymConst;
+ } else if (get_opt_closed_world() &&
+ is_Sel(ptr) &&
+ get_irg_callee_info_state(current_ir_graph) == irg_callee_info_consistent) {
+ /* If all possible callees are const functions, we can remove the memory edge. */
+ int i, n_callees = get_Call_n_callees(call);
+ if (n_callees == 0) {
+ /* This is kind of strange: dying code or a Call that will raise an exception
+ when executed as there is no implementation to call. So better not
+ optimize. */
+ return;
+ }
+
+ /* note that const function are a subset of pure ones */
+ prop = mtp_property_const | mtp_property_pure;
+ for (i = 0; i < n_callees; ++i) {
+ ent = get_Call_callee(call, i);
+ if (ent == unknown_entity) {
+ /* we don't know which entity is called here */
+ return;
+ }
+ prop &= get_entity_additional_properties(ent);
+ if (prop == mtp_no_property)
+ return;
+ }
+ ++ctx->n_calls_Sel;
+ } else
+ return;
+
+ /* ok, if we get here we found a call to a const or a pure function */
+ if (prop & mtp_property_pure) {
+ set_irn_link(call, ctx->pure_call_list);
+ ctx->pure_call_list = call;
+ } else {
+ set_irn_link(call, ctx->const_call_list);
+ ctx->const_call_list = call;
+ }
+ } else if (is_Proj(node)) {
+ /*
+ * Collect all memory and exception Proj's from
+ * calls.
+ */
+ call = get_Proj_pred(node);
+ if (! is_Call(call))
+ return;
+
+ /* collect the Proj's in the Proj list */
+ switch (get_Proj_proj(node)) {
+ case pn_Call_M_regular:
+ case pn_Call_X_except:
+ case pn_Call_X_regular:
+ case pn_Call_M_except:
+ set_irn_link(node, ctx->proj_list);
+ ctx->proj_list = node;
+ break;
+ default:
+ break;
+ }
+ }
+} /* collect_const_and_pure_calls */
+
+/**
+ * Fix the list of collected Calls.
*
- * Note: By "const function" we understand a function that did neither
- * read nor write memory. Hence its result depends solely on its
- * arguments.
+ * @param irg the graph that contained calls to pure functions
+ * @param call_list the list of all call sites of const functions
+ * @param proj_list the list of all memory/exception Proj's of this call sites
*/
-static void rem_mem_from_const_fkt_calls(ir_node *node, void *env)
-{
- env_t *ctx = env;
- ir_node *call, *ptr, *mem;
- entity *ent;
-
- if (get_irn_op(node) == op_Call) {
- call = node;
-
- set_irn_link(call, NULL);
-
- ptr = get_Call_ptr(call);
- if (get_irn_op(ptr) == op_SymConst && get_SymConst_kind(ptr) == symconst_addr_ent) {
- ent = get_SymConst_entity(ptr);
-
- if ((get_entity_additional_properties(ent) & mtp_property_const) == 0)
- return;
- ++ctx->n_calls_removed_SymConst;
- }
- else if (get_irn_op(ptr) == op_Sel &&
- get_irg_callee_info_state(current_ir_graph) == irg_callee_info_consistent) {
- /* If all possible callees are real functions, we can remove the memory edge. */
- int i, n_callees = get_Call_n_callees(call);
- if (n_callees == 0)
- /* This is kind of strange: dying code or a Call that will raise an exception
- when executed as there is no implementation to call. So better not
- optimize. */
- return;
- for (i = 0; i < n_callees; ++i) {
- ent = get_Call_callee(call, i);
- if ((get_entity_additional_properties(ent) & mtp_property_const) == 0)
- return;
- }
- ++ctx->n_calls_removed_Sel;
- }
- else
- return;
-
- /* ok, if we get here we found a call to a const function,
- * route the NoMem node to the call */
- mem = get_Call_mem(call);
-
- set_irn_link(call, mem);
- set_Call_mem(call, new_r_NoMem(current_ir_graph));
-
- /* finally, this call can float */
- set_irn_pinned(call, op_pin_state_floats);
-
- hook_func_call(current_ir_graph, call);
-
- ctx->changed = 1;
- }
- else if (get_irn_op(node) == op_Proj) {
- /*
- * Remove memory and exception Proj's from
- * const function calls.
- */
- call = get_Proj_pred(node);
- if ((get_irn_op(call) != op_Call) ||
- (get_irn_op(get_Call_mem(call)) != op_NoMem))
- return;
-
- switch (get_Proj_proj(node)) {
- case pn_Call_M_regular: {
- ir_node *old_mem = get_irn_link(call);
- if (old_mem)
- exchange(node, old_mem);
- } break;
- case pn_Call_X_except:
- case pn_Call_M_except:
- exchange(node, new_Bad());
- break;
- default: ;
- }
- }
+static void fix_const_call_list(ir_graph *irg, ir_node *call_list, ir_node *proj_list) {
+ ir_node *call, *next, *mem, *proj;
+ int exc_changed = 0;
+ ir_graph *rem = current_ir_graph;
+
+ current_ir_graph = irg;
+
+ /* First step: fix all calls by removing it's memory input.
+ It's original memory input is preserved in their link fields. */
+ for (call = call_list; call; call = next) {
+ next = get_irn_link(call);
+ mem = get_Call_mem(call);
+
+ set_irn_link(call, mem);
+ set_Call_mem(call, get_irg_no_mem(irg));
+
+ /*
+ * Sorrily we cannot simply set the node to 'float'.
+ * There is a reason for that:
+ *
+ * - The call might be inside a loop/if that is NOT entered
+ * and calls a endless function. Setting the call to float
+ * would allow to move it out from the loop/if causing this
+ * function be called even if the loop/if is not entered ...
+ *
+ * This could be fixed using post-dominators for calls and Pin nodes
+ * but need some more analyzes to ensure that a call that potential
+ * never returns is not executed before some code that generates
+ * observable states...
+ */
+
+ /* finally, this call can float
+ set_irn_pinned(call, op_pin_state_floats); */
+ hook_func_call(irg, call);
+ }
+
+ /* Second step: fix all Proj's */
+ for (proj = proj_list; proj; proj = next) {
+ next = get_irn_link(proj);
+ call = get_Proj_pred(proj);
+ mem = get_irn_link(call);
+
+ /* beware of calls in the pure call list */
+ if (! mem || get_irn_op(mem) == op_Call)
+ continue;
+ assert(get_irn_mode(mem) == mode_M);
+
+ switch (get_Proj_proj(proj)) {
+ case pn_Call_M_regular: {
+ /* in dead code there might be cycles where proj == mem */
+ if (proj != mem)
+ exchange(proj, mem);
+ break;
+ }
+ case pn_Call_X_except:
+ case pn_Call_M_except:
+ exc_changed = 1;
+ exchange(proj, get_irg_bad(irg));
+ break;
+ case pn_Call_X_regular: {
+ ir_node *block = get_nodes_block(call);
+ exc_changed = 1;
+ exchange(proj, new_r_Jmp(irg, block));
+ break;
+ }
+ default:
+ ;
+ }
+ }
+
+ /* changes were done ... */
+ set_irg_outs_inconsistent(irg);
+ set_irg_loopinfo_state(irg, loopinfo_cf_inconsistent);
+
+ if (exc_changed) {
+ /* ... including exception edges */
+ set_irg_doms_inconsistent(irg);
+ }
+ current_ir_graph = rem;
+} /* fix_const_call_list */
+
+/**
+ * Walker: Collect all calls to nothrow functions
+ * to lists. Collect all Proj(Call) nodes into a Proj list.
+ */
+static void collect_nothrow_calls(ir_node *node, void *env) {
+ env_t *ctx = env;
+ ir_node *call, *ptr;
+ ir_entity *ent;
+ unsigned prop;
+
+ if (is_Call(node)) {
+ call = node;
+
+ /* set the link to NULL for all non-const/pure calls */
+ set_irn_link(call, NULL);
+ ptr = get_Call_ptr(call);
+ if (is_SymConst_addr_ent(ptr)) {
+ ent = get_SymConst_entity(ptr);
+
+ prop = get_entity_additional_properties(ent);
+ if ((prop & mtp_property_nothrow) == 0)
+ return;
+ ++ctx->n_calls_SymConst;
+ } else if (get_opt_closed_world() &&
+ is_Sel(ptr) &&
+ get_irg_callee_info_state(current_ir_graph) == irg_callee_info_consistent) {
+ /* If all possible callees are nothrow functions, we can remove the exception edge. */
+ int i, n_callees = get_Call_n_callees(call);
+ if (n_callees == 0) {
+ /* This is kind of strange: dying code or a Call that will raise an exception
+ when executed as there is no implementation to call. So better not
+ optimize. */
+ return;
+ }
+
+ /* note that const function are a subset of pure ones */
+ prop = mtp_property_nothrow;
+ for (i = 0; i < n_callees; ++i) {
+ ent = get_Call_callee(call, i);
+ if (ent == unknown_entity) {
+ /* we don't know which entity is called here */
+ return;
+ }
+ prop &= get_entity_additional_properties(ent);
+ if (prop == mtp_no_property)
+ return;
+ }
+ ++ctx->n_calls_Sel;
+ } else
+ return;
+
+ /* ok, if we get here we found a call to a nothrow function */
+ set_irn_link(call, ctx->nothrow_call_list);
+ ctx->nothrow_call_list = call;
+ } else if (is_Proj(node)) {
+ /*
+ * Collect all memory and exception Proj's from
+ * calls.
+ */
+ call = get_Proj_pred(node);
+ if (! is_Call(call))
+ return;
+
+ /* collect the Proj's in the Proj list */
+ switch (get_Proj_proj(node)) {
+ case pn_Call_M_regular:
+ case pn_Call_X_except:
+ case pn_Call_X_regular:
+ case pn_Call_M_except:
+ set_irn_link(node, ctx->proj_list);
+ ctx->proj_list = node;
+ break;
+ default:
+ break;
+ }
+ }
+} /* collect_nothrow_calls */
+
+/**
+ * Fix the list of collected nothrow Calls.
+ *
+ * @param irg the graph that contained calls to pure functions
+ * @param call_list the list of all call sites of const functions
+ * @param proj_list the list of all memory/exception Proj's of this call sites
+ */
+static void fix_nothrow_call_list(ir_graph *irg, ir_node *call_list, ir_node *proj_list) {
+ ir_node *call, *next, *proj;
+ int exc_changed = 0;
+ ir_graph *rem = current_ir_graph;
+
+ current_ir_graph = irg;
+
+ /* First step: go through the list of calls and mark them. */
+ for (call = call_list; call; call = next) {
+ next = get_irn_link(call);
+
+ /* current_ir_graph is in memory anyway, so it's a good marker */
+ set_irn_link(call, ¤t_ir_graph);
+ hook_func_call(irg, call);
+ }
+
+ /* Second step: Remove all exception Proj's */
+ for (proj = proj_list; proj; proj = next) {
+ next = get_irn_link(proj);
+ call = get_Proj_pred(proj);
+
+ /* handle only marked calls */
+ if (get_irn_link(call) != ¤t_ir_graph)
+ continue;
+
+ /* kill any exception flow */
+ switch (get_Proj_proj(proj)) {
+ case pn_Call_X_except:
+ case pn_Call_M_except:
+ exc_changed = 1;
+ exchange(proj, get_irg_bad(irg));
+ break;
+ case pn_Call_X_regular: {
+ ir_node *block = get_nodes_block(call);
+ exc_changed = 1;
+ exchange(proj, new_r_Jmp(irg, block));
+ break;
+ }
+ default:
+ ;
+ }
+ }
+
+ /* changes were done ... */
+ set_irg_outs_inconsistent(irg);
+ set_irg_loopinfo_state(irg, loopinfo_cf_inconsistent);
+
+ if (exc_changed) {
+ /* ... including exception edges */
+ set_irg_doms_inconsistent(irg);
+ }
+ current_ir_graph = rem;
+} /* fix_nothrow_call_list */
+
+/* marking */
+#define SET_IRG_READY(irg) rbitset_set(ready_set, get_irg_idx(irg))
+#define IS_IRG_READY(irg) rbitset_is_set(ready_set, get_irg_idx(irg))
+#define SET_IRG_BUSY(irg) rbitset_set(busy_set, get_irg_idx(irg))
+#define CLEAR_IRG_BUSY(irg) rbitset_clear(busy_set, get_irg_idx(irg))
+#define IS_IRG_BUSY(irg) rbitset_is_set(busy_set, get_irg_idx(irg))
+
+/* forward */
+static unsigned check_const_or_pure_function(ir_graph *irg, int top);
+static unsigned check_nothrow_or_malloc(ir_graph *irg, int top);
+
+/**
+ * Calculate the bigger property of two. Handle the temporary flag right.
+ */
+static unsigned max_property(unsigned a, unsigned b) {
+ unsigned r, t = (a | b) & mtp_temporary;
+ a &= ~mtp_temporary;
+ b &= ~mtp_temporary;
+
+ if (a == mtp_no_property || b == mtp_no_property)
+ return mtp_no_property;
+ r = a > b ? a : b;
+ return r | t;
+} /* max_property */
+
+/**
+ * Follow the memory chain starting at node and determine
+ * the mtp_property.
+ *
+ * @return mtp_property_const if only calls of const functions are detected
+ * mtp_property_pure if only Loads and const/pure
+ * calls detected
+ * mtp_no_property else
+ */
+static unsigned _follow_mem(ir_node *node) {
+ unsigned m, mode = mtp_property_const;
+ ir_node *ptr;
+ int i;
+
+ for (;;) {
+ if (mode == mtp_no_property)
+ return mtp_no_property;
+
+ if (irn_visited(node))
+ return mode;
+
+ mark_irn_visited(node);
+
+ switch (get_irn_opcode(node)) {
+ case iro_Proj:
+ node = get_Proj_pred(node);
+ break;
+
+ case iro_NoMem:
+ /* finish here */
+ return mode;
+
+ case iro_Phi:
+ case iro_Sync:
+ /* do a dfs search */
+ for (i = get_irn_arity(node) - 1; i >= 0; --i) {
+ m = _follow_mem(get_irn_n(node, i));
+ mode = max_property(mode, m);
+ if (mode == mtp_no_property)
+ return mtp_no_property;
+ }
+ return mode;
+
+ case iro_Load:
+ /* Beware volatile Loads are NOT allowed in pure functions. */
+ if (get_Load_volatility(node) == volatility_is_volatile)
+ return mtp_no_property;
+ mode = max_property(mode, mtp_property_pure);
+ node = get_Load_mem(node);
+ break;
+
+ case iro_Call:
+ /* A call is only tolerable if its either constant or pure. */
+ ptr = get_Call_ptr(node);
+ if (get_irn_op(ptr) == op_SymConst &&
+ get_SymConst_kind(ptr) == symconst_addr_ent) {
+ ir_entity *ent = get_SymConst_entity(ptr);
+ ir_graph *irg = get_entity_irg(ent);
+
+ if (irg == current_ir_graph) {
+ /* A self-recursive call. The property did not depend on this call. */
+ } else if (irg == NULL) {
+ m = get_entity_additional_properties(ent) & (mtp_property_const|mtp_property_pure);
+ mode = max_property(mode, m);
+ } else if (irg != NULL) {
+ /* we have a graph, analyze it. */
+ m = check_const_or_pure_function(irg, /*top=*/0);
+ mode = max_property(mode, m);
+ }
+ } else
+ return mtp_no_property;
+ node = get_Call_mem(node);
+ break;
+
+ default:
+ return mtp_no_property;
+ }
+ }
+} /* _follow_mem */
+
+/**
+ * Follow the memory chain starting at node and determine
+ * the mtp_property.
+ *
+ * @return mtp_property_const if only calls of const functions are detected
+ * mtp_property_pure if only Loads and const/pure calls detected
+ * mtp_no_property else
+ */
+static unsigned follow_mem(ir_node *node, unsigned mode) {
+ unsigned m;
+
+ m = _follow_mem(node);
+ return max_property(mode, m);
+} /* follow_mem */
+
+/**
+ * Check if a graph represents a const or a pure function.
+ *
+ * @param irg the graph to check
+ * @param top if set, this is the top call
+ */
+static unsigned check_const_or_pure_function(ir_graph *irg, int top) {
+ ir_node *end, *endbl;
+ int j;
+ unsigned prop = get_irg_additional_properties(irg);
+ ir_graph *rem = current_ir_graph;
+
+ if (prop & mtp_property_const) {
+ /* already marked as a const function */
+ return mtp_property_const;
+ }
+ if (prop & mtp_property_pure) {
+ /* already marked as a pure function */
+ return mtp_property_pure;
+ }
+
+ if (IS_IRG_READY(irg)) {
+ /* already checked */
+ return mtp_no_property;
+ }
+ if (IS_IRG_BUSY(irg)) {
+ /* we are still evaluate this method. Be optimistic,
+ return the best possible so far but mark the result as temporary. */
+ return mtp_temporary | mtp_property_const;
+ }
+ SET_IRG_BUSY(irg);
+
+ end = get_irg_end(irg);
+ endbl = get_nodes_block(end);
+ prop = mtp_property_const;
+
+ current_ir_graph = irg;
+
+ inc_irg_visited(irg);
+ /* mark the initial mem: recursion of follow_mem stops here */
+ mark_irn_visited(get_irg_initial_mem(irg));
+
+ /* visit every Return */
+ for (j = get_Block_n_cfgpreds(endbl) - 1; j >= 0; --j) {
+ ir_node *node = get_Block_cfgpred(endbl, j);
+ ir_opcode code = get_irn_opcode(node);
+ ir_node *mem;
+
+ /* Bad nodes usually do NOT produce anything, so it's ok */
+ if (code == iro_Bad)
+ continue;
+
+ if (code == iro_Return) {
+ mem = get_Return_mem(node);
+
+ /* Bad nodes usually do NOT produce anything, so it's ok */
+ if (is_Bad(mem))
+ continue;
+
+ if (mem != get_irg_initial_mem(irg))
+ prop = max_property(prop, follow_mem(mem, prop));
+ } else {
+ /* Exception found. Cannot be const or pure. */
+ prop = mtp_no_property;
+ break;
+ }
+ if (prop == mtp_no_property)
+ break;
+ }
+
+ if (prop != mtp_no_property) {
+ /* check, if a keep-alive exists */
+ for (j = get_End_n_keepalives(end) - 1; j >= 0; --j) {
+ ir_node *mem = get_End_keepalive(end, j);
+
+ if (mode_M != get_irn_mode(mem))
+ continue;
+
+ prop = max_property(prop, follow_mem(mem, prop));
+ if (prop == mtp_no_property)
+ break;
+ }
+ }
+
+ if (prop != mtp_no_property) {
+ if (top || (prop & mtp_temporary) == 0) {
+ /* We use the temporary flag here to mark optimistic result.
+ Set the property only if we are sure that it does NOT base on
+ temporary results OR if we are at top-level. */
+ set_irg_additional_property(irg, prop & ~mtp_temporary);
+ SET_IRG_READY(irg);
+ }
+ }
+ if (top)
+ SET_IRG_READY(irg);
+ CLEAR_IRG_BUSY(irg);
+ current_ir_graph = rem;
+ return prop;
+} /* check_const_or_pure_function */
+
+/**
+ * Handle calls to const functions.
+ *
+ * @param ctx context
+ */
+static void handle_const_Calls(env_t *ctx) {
+ int i;
+
+ ctx->n_calls_SymConst = 0;
+ ctx->n_calls_Sel = 0;
+
+ /* all calls of const functions can be transformed */
+ for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
+ ir_graph *irg = get_irp_irg(i);
+
+ ctx->const_call_list = NULL;
+ ctx->pure_call_list = NULL;
+ ctx->proj_list = NULL;
+ irg_walk_graph(irg, NULL, collect_const_and_pure_calls, ctx);
+
+ if (ctx->const_call_list) {
+ fix_const_call_list(irg, ctx->const_call_list, ctx->proj_list);
+
+ /* this graph was changed, invalidate analysis info */
+ set_irg_outs_inconsistent(irg);
+ set_irg_doms_inconsistent(irg);
+ }
+ }
+} /* handle_const_Calls */
+
+/**
+ * Handle calls to nothrow functions.
+ *
+ * @param ctx context
+ */
+static void handle_nothrow_Calls(env_t *ctx) {
+ int i;
+
+ ctx->n_calls_SymConst = 0;
+ ctx->n_calls_Sel = 0;
+
+ /* all calls of const functions can be transformed */
+ for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
+ ir_graph *irg = get_irp_irg(i);
+
+ ctx->nothrow_call_list = NULL;
+ ctx->proj_list = NULL;
+ irg_walk_graph(irg, NULL, collect_nothrow_calls, ctx);
+
+ if (ctx->nothrow_call_list) {
+ fix_nothrow_call_list(irg, ctx->nothrow_call_list, ctx->proj_list);
+
+ /* this graph was changed, invalidate analysis info */
+ set_irg_outs_inconsistent(irg);
+ set_irg_doms_inconsistent(irg);
+ }
+ }
}
+/**
+ * Check, whether a given node represents a return value of
+ * a malloc like function (ie, new heap allocated memory).
+ *
+ * @param node the node to check
+ */
+static int is_malloc_call_result(const ir_node *node) {
+ if (is_Alloc(node) && get_Alloc_where(node) == heap_alloc) {
+ /* Firm style high-level allocation */
+ return 1;
+ }
+ if (is_alloc_entity != NULL && is_Call(node)) {
+ ir_node *ptr = get_Call_ptr(node);
+
+ if (is_SymConst_addr_ent(ptr)) {
+ ir_entity *ent = get_SymConst_entity(ptr);
+ return is_alloc_entity(ent);
+ }
+ }
+ return 0;
+} /* is_malloc_call_result */
+
+/**
+ * Update a property depending on a call property.
+ */
+static unsigned update_property(unsigned orig_prop, unsigned call_prop) {
+ unsigned t = (orig_prop | call_prop) & mtp_temporary;
+ unsigned r = orig_prop & call_prop;
+ return r | t;
+} /** update_property */
+
+/**
+ * Check if a graph represents a nothrow or a malloc function.
+ *
+ * @param irg the graph to check
+ * @param top if set, this is the top call
+ */
+static unsigned check_nothrow_or_malloc(ir_graph *irg, int top) {
+ ir_node *end_blk = get_irg_end_block(irg);
+ int i, j;
+ unsigned curr_prop = mtp_property_malloc | mtp_property_nothrow;
+
+ if (IS_IRG_READY(irg)) {
+ /* already checked */
+ return get_irg_additional_properties(irg);
+ }
+ if (IS_IRG_BUSY(irg)) {
+ /* we are still evaluate this method. Be optimistic,
+ return the best possible so far but mark the result as temporary. */
+ return mtp_temporary | mtp_property_malloc | mtp_property_nothrow;
+ }
+ SET_IRG_BUSY(irg);
+
+ for (i = get_Block_n_cfgpreds(end_blk) - 1; i >= 0; --i) {
+ ir_node *pred = get_Block_cfgpred(end_blk, i);
+
+ if (is_Return(pred)) {
+ if (curr_prop & mtp_property_malloc) {
+ /* check, if malloc is called here */
+ for (j = get_Return_n_ress(pred) - 1; j >= 0; --j) {
+ const ir_node *res = get_Return_res(pred, j);
+ //const ir_node *irn = skip_Proj_const(res);
+ if (is_malloc_call_result(res)) {
+ /* ok, this is a malloc */
+ } else if (is_Call(res)) {
+ ir_node *ptr = get_Call_ptr(res);
+
+ if (is_SymConst_addr_ent(ptr)) {
+ /* a direct call */
+ ir_entity *ent = get_SymConst_entity(ptr);
+ ir_graph *callee = get_entity_irg(ent);
+
+ if (callee == irg) {
+ /* A self-recursive call. The property did not depend on this call. */
+ } else if (callee != NULL) {
+ unsigned prop = check_nothrow_or_malloc(callee, /*top=*/0);
+ curr_prop = update_property(curr_prop, prop);
+ } else {
+ curr_prop = update_property(curr_prop, get_entity_additional_properties(ent));
+ }
+ } else if (get_opt_closed_world() &&
+ is_Sel(ptr) &&
+ get_irg_callee_info_state(irg) == irg_callee_info_consistent) {
+ /* check if all possible callees are malloc functions. */
+ int i, n_callees = get_Call_n_callees(res);
+ if (n_callees == 0) {
+ /* This is kind of strange: dying code or a Call that will raise an exception
+ when executed as there is no implementation to call. So better not
+ optimize. */
+ curr_prop &= ~mtp_property_malloc;
+ continue;
+ }
+
+ for (i = 0; i < n_callees; ++i) {
+ ir_entity *ent = get_Call_callee(res, i);
+ if (ent == unknown_entity) {
+ /* we don't know which entity is called here */
+ curr_prop &= ~mtp_property_malloc;
+ break;
+ }
+ if ((get_entity_additional_properties(ent) & mtp_property_malloc) == 0) {
+ curr_prop &= ~mtp_property_malloc;
+ break;
+ }
+ }
+ /* if we pass the for cycle, malloc is still ok */
+ } else {
+ /* unknown call */
+ curr_prop &= ~mtp_property_malloc;
+ }
+ }
+ }
+ }
+ } else if (curr_prop & mtp_property_nothrow) {
+ /* exception flow detected */
+ pred = skip_Proj(pred);
+
+ if (is_Call(pred)) {
+ ir_node *ptr = get_Call_ptr(pred);
+
+ if (is_SymConst_addr_ent(ptr)) {
+ /* a direct call */
+ ir_entity *ent = get_SymConst_entity(ptr);
+ ir_graph *callee = get_entity_irg(ent);
+
+ if (callee == irg) {
+ /* A self-recursive call. The property did not depend on this call. */
+ } else if (callee != NULL) {
+ unsigned prop = check_nothrow_or_malloc(callee, /*top=*/0);
+ curr_prop = update_property(curr_prop, prop);
+ } else {
+ curr_prop = update_property(curr_prop, get_entity_additional_properties(ent));
+ }
+ } else if (get_opt_closed_world() &&
+ is_Sel(ptr) &&
+ get_irg_callee_info_state(irg) == irg_callee_info_consistent) {
+ /* check if all possible callees are nothrow functions. */
+ int i, n_callees = get_Call_n_callees(pred);
+ if (n_callees == 0) {
+ /* This is kind of strange: dying code or a Call that will raise an exception
+ when executed as there is no implementation to call. So better not
+ optimize. */
+ curr_prop &= ~mtp_property_nothrow;
+ continue;
+ }
+
+ for (i = 0; i < n_callees; ++i) {
+ ir_entity *ent = get_Call_callee(pred, i);
+ if (ent == unknown_entity) {
+ /* we don't know which entity is called here */
+ curr_prop &= ~mtp_property_nothrow;
+ break;
+ }
+ if ((get_entity_additional_properties(ent) & mtp_property_nothrow) == 0) {
+ curr_prop &= ~mtp_property_nothrow;
+ break;
+ }
+ }
+ /* if we pass the for cycle, nothrow is still ok */
+ } else {
+ /* unknown call */
+ curr_prop &= ~mtp_property_nothrow;
+ }
+ } else {
+ /* real exception flow possible. */
+ curr_prop &= ~mtp_property_nothrow;
+ }
+ }
+ if ((curr_prop & ~mtp_temporary) == mtp_no_property) {
+ /* no need to search further */
+ break;
+ }
+ }
+ if (curr_prop != mtp_no_property) {
+ if (top || (curr_prop & mtp_temporary) == 0) {
+ /* We use the temporary flag here to mark an optimistic result.
+ Set the property only if we are sure that it does NOT base on
+ temporary results OR if we are at top-level. */
+ set_irg_additional_property(irg, curr_prop & ~mtp_temporary);
+ SET_IRG_READY(irg);
+ }
+ }
+ if (top)
+ SET_IRG_READY(irg);
+ CLEAR_IRG_BUSY(irg);
+ return curr_prop;
+} /* check_nothrow_or_malloc */
+
/*
* optimize function calls by handling const functions
*/
void optimize_funccalls(int force_run)
{
- int i, j;
- int change;
- unsigned num_pure = 0;
-
- if (! get_opt_real_func_call())
- return;
-
- /* first step: detect, which functions are const, i.e. do NOT touch any memory */
- for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
- ir_graph *irg = get_irp_irg(i);
- ir_node *end = get_irg_end(irg);
- ir_node *endbl = get_nodes_block(end);
-
- change = 0;
-
- if (get_irg_additional_properties(irg) & mtp_property_const) {
- /* already marked as a const function */
- ++num_pure;
- }
- else {
- /* visit every Return */
- for (j = get_Block_n_cfgpreds(endbl) - 1; j >= 0; --j) {
- ir_node *node = get_Block_cfgpred(endbl, j);
- ir_op *op = get_irn_op(node);
- ir_node *mem;
-
- /* Bad nodes usually do NOT produce anything, so it's ok */
- if (op == op_Bad)
- continue;
-
- if (op == op_Return) {
- mem = get_Return_mem(node);
-
- /* Bad nodes usually do NOT produce anything, so it's ok */
- if (is_Bad(mem))
- continue;
-
- change = mem != get_irg_initial_mem(irg);
- if (change)
- break;
- }
- else {
- /* exception found */
- change = 1;
- break;
- }
- }
-
- if (! change) {
- /* check, if a keep-alive exists */
- for (j = get_End_n_keepalives(end) - 1; j >= 0; --j) {
- ir_node *mem = get_End_keepalive(end, j);
-
- if (mode_M != get_irn_mode(mem))
- continue;
-
- change = mem != get_irg_initial_mem(irg);
- if (change)
- break;
- }
- }
-
- if (! change) {
- /* no memory changes found, it's a const function */
- set_irg_additional_property(irg, mtp_property_const);
- ++num_pure;
- }
- }
- }
-
- if (force_run || num_pure > 0) {
- env_t ctx;
-
- ctx.n_calls_removed_SymConst = 0;
- ctx.n_calls_removed_Sel = 0;
-
- /* all calls of pure functions can be transformed into FuncCalls */
- for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
- ir_graph *irg = get_irp_irg(i);
-
- /* no need to do this on const functions */
- if ((get_irg_additional_properties(irg) & mtp_property_const) == 0) {
- ctx.changed = 0;
- irg_walk_graph(irg, NULL, rem_mem_from_const_fkt_calls, &ctx);
-
- if (ctx.changed) {
- /* changes were done */
- set_irg_outs_inconsistent(irg);
- set_irg_loopinfo_state(current_ir_graph, loopinfo_cf_inconsistent);
- }
- }
- }
-
- if (get_firm_verbosity()) {
- printf("Detected %d graphs without side effects.\n", num_pure);
- printf("Optimizes %d(SymConst) + %d(Sel) calls to const functions.\n",
- ctx.n_calls_removed_SymConst, ctx.n_calls_removed_Sel);
- }
- }
- else {
- if (get_firm_verbosity()) {
- printf("No graphs without side effects detected\n");
- }
- }
-}
+ int i, last_idx;
+ unsigned num_const = 0;
+ unsigned num_pure = 0;
+ unsigned num_nothrow = 0;
+ unsigned num_malloc = 0;
+
+ /* prepare: mark all graphs as not analyzed */
+ last_idx = get_irp_last_idx();
+ ready_set = rbitset_malloc(last_idx);
+ busy_set = rbitset_malloc(last_idx);
+
+ /* first step: detect, which functions are nothrow or malloc */
+ DB((dbg, LEVEL_2, "Detecting nothrow and malloc properties ...\n"));
+ for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
+ ir_graph *irg = get_irp_irg(i);
+ unsigned prop = check_nothrow_or_malloc(irg, /*top=*/1);
+
+ if (prop & mtp_property_nothrow) {
+ ++num_nothrow;
+ DB((dbg, LEVEL_2, "%+F has the nothrow property\n", irg));
+ } else if (prop & mtp_property_malloc) {
+ ++num_malloc;
+ DB((dbg, LEVEL_2, "%+F has the malloc property\n", irg));
+ }
+ }
+
+ /* second step: remove exception edges: this must be done before the
+ detection of const and pure functions take place. */
+ if (force_run || num_nothrow > 0) {
+ env_t ctx;
+
+ handle_nothrow_Calls(&ctx);
+ DB((dbg, LEVEL_1, "Detected %u nothrow graphs, %u malloc graphs.\n", num_nothrow, num_malloc));
+ DB((dbg, LEVEL_1, "Optimizes %u(SymConst) + %u(Sel) calls to nothrow functions.\n",
+ ctx.n_calls_SymConst, ctx.n_calls_Sel));
+ } else {
+ DB((dbg, LEVEL_1, "No graphs without side effects detected\n"));
+ }
+
+ rbitset_clear_all(ready_set, last_idx);
+ rbitset_clear_all(busy_set, last_idx);
+
+ /* third step: detect, which functions are const or pure */
+ DB((dbg, LEVEL_2, "Detecting const and pure properties ...\n"));
+ for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
+ ir_graph *irg = get_irp_irg(i);
+ unsigned prop = check_const_or_pure_function(irg, /*top=*/1);
+
+ if (prop & mtp_property_const) {
+ ++num_const;
+ DB((dbg, LEVEL_2, "%+F has the const property\n", irg));
+ } else if (prop & mtp_property_pure) {
+ ++num_pure;
+ DB((dbg, LEVEL_2, "%+F has the pure property\n", irg));
+ }
+ }
+
+ if (force_run || num_const > 0) {
+ env_t ctx;
+
+ handle_const_Calls(&ctx);
+ DB((dbg, LEVEL_1, "Detected %u const graphs, %u pure graphs.\n", num_const, num_pure));
+ DB((dbg, LEVEL_1, "Optimizes %u(SymConst) + %u(Sel) calls to const functions.\n",
+ ctx.n_calls_SymConst, ctx.n_calls_Sel));
+ } else {
+ DB((dbg, LEVEL_1, "No graphs without side effects detected\n"));
+ }
+ xfree(busy_set);
+ xfree(ready_set);
+} /* optimize_funccalls */
+
+/* initialize the funccall optimization */
+void firm_init_funccalls(void) {
+ FIRM_DBG_REGISTER(dbg, "firm.opt.funccalls");
+// firm_dbg_set_mask(dbg, -1);
+} /* firm_init_funccalls */
projects / libfirm / blobdiff