/*
* Project: libFIRM
- * File name: ir/opt/ldstopt.c
+ * File name: ir/opt/funccall.c
* Purpose: optimization of function calls
- * Author:
+ * Author: Michael Beck
* Created:
* CVS-ID: $Id$
- * Copyright: (c) 1998-2004 Universität Karlsruhe
+ * Copyright: (c) 1998-2004 Universit�t Karlsruhe
* Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
*/
#include "irnode_t.h"
#include "dbginfo_t.h"
#include "irflag_t.h"
#include "ircons.h"
-#include "eset.h"
#include "funccall.h"
#include "irhooks.h"
/**
- * The walker environment for rem_mem_from_real_fkt_calls
+ * The walker environment for rem_mem_from_const_fkt_calls
*/
typedef struct _env_t {
- eset *pure_fkt; /**< set containing all real functions */
- int changed; /**< flag, is set if a graph was changed */
+ int changed; /**< flag, is set if a graph was changed */
+ int n_calls_removed_SymConst;
+ int n_calls_removed_Sel;
} env_t;
/**
- * remove memory from real function calls by rerouting
+ * remove memory from const function calls by rerouting
* it's ProjM and connection the call with a NoMem node.
*
- * Note: By "real function" we understand a function that did neither
- * read nor write memory.
+ * Note: By "const function" we understand a function that did neither
+ * read nor write memory. Hence its result depends solely on its
+ * arguments.
*/
-static void rem_mem_from_real_fkt_calls(ir_node *node, void *env)
+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_Proj || get_irn_mode(node) != mode_M)
- return;
-
- /* look at Memory Proj's */
- call = get_Proj_pred(node);
- if (get_irn_op(call) != op_Call)
- return;
+ if (get_irn_op(node) == op_Call) {
+ call = node;
- ptr = get_Call_ptr(call);
- if (get_irn_op(ptr) != op_SymConst || get_SymConst_kind(ptr) != symconst_addr_ent)
- return;
+ set_irn_link(call, NULL);
- ent = get_SymConst_entity(ptr);
+ 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 (! eset_contains(ctx->pure_fkt, ent))
- return;
+ 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 (ent == unknown_entity) {
+ /* we don't know which entity is called here */
+ return;
+ }
+ 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 pure function,
- * route the NoMem node to the call */
- mem = get_Call_mem(call);
+ /* 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);
- exchange(node, mem);
- set_Call_mem(call, new_r_NoMem(current_ir_graph));
+ set_irn_link(call, mem);
+ set_Call_mem(call, new_r_NoMem(current_ir_graph));
- /* finally, this call can floats */
- set_irn_pinned(call, op_pin_state_floats);
+ /* finally, this call can float */
+ set_irn_pinned(call, op_pin_state_floats);
- hook_func_call(current_ir_graph, call);
+ hook_func_call(current_ir_graph, call);
- ctx->changed = 1;
+ 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: ;
+ }
+ }
}
/*
- * optimize function calls by handling real functions
+ * optimize function calls by handling const functions
*/
-void optimize_funccalls(void)
+void optimize_funccalls(int force_run)
{
- int i, n, j, k;
+ int i, j;
int change;
unsigned num_pure = 0;
- eset *pure_fkt = eset_create();
- if (! get_opt_real_func_call())
+ if (! get_opt_real_function_call())
return;
- /* first step: detect, which functions are pure, ie do NOT change any memory */
- for (i = 0, n = get_irp_n_irgs(); i < n; ++i) {
+ /* 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;
- /* visit every Return */
- for (j = 0, k = get_Block_n_cfgpreds(endbl); j < k; ++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);
+ 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 (is_Bad(mem))
+ if (op == op_Bad)
continue;
- change = mem != get_irg_initial_mem(irg);
- if (change)
+ 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;
+ }
}
- else {
- /* exception found */
- change = 1;
- break;
- }
- }
- if (! change) {
- /* check, if a keep-alive exists */
- for (j = 0, k = get_End_n_keepalives(end); j < k; ++j) {
- ir_node *mem = get_End_keepalive(end, j);
+ 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;
+ if (mode_M != get_irn_mode(mem))
+ continue;
- change = mem != get_irg_initial_mem(irg);
- if (change)
- break;
+ change = mem != get_irg_initial_mem(irg);
+ if (change)
+ break;
+ }
}
- }
- if (! change) {
- eset_insert(pure_fkt, get_irg_entity(irg));
- ++num_pure;
+ if (! change) {
+ /* no memory changes found, it's a const function */
+ set_irg_additional_property(irg, mtp_property_const);
+ ++num_pure;
+ }
}
}
- if (num_pure > 0) {
+ if (force_run || num_pure > 0) {
env_t ctx;
- ctx.pure_fkt = pure_fkt;
+ ctx.n_calls_removed_SymConst = 0;
+ ctx.n_calls_removed_Sel = 0;
/* all calls of pure functions can be transformed into FuncCalls */
- for (i = 0, n = get_irp_n_irgs(); i < n; ++i) {
+ for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
ir_graph *irg = get_irp_irg(i);
- ctx.changed = 0;
- irg_walk_graph(irg, NULL, rem_mem_from_real_fkt_calls, &ctx);
+ /* 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 (ctx.changed) {
+ /* changes were done */
+ set_irg_outs_inconsistent(irg);
+ set_irg_loopinfo_state(current_ir_graph, loopinfo_cf_inconsistent);
+ }
}
}
- }
- eset_destroy(pure_fkt);
+ 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");
+ }
+ }
}
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