/*
- * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
+ * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
*
* This file is part of libFirm.
*
* @author Christoph Mallon
* @version $Id$
*/
-
-#ifdef HAVE_CONFIG_H
#include "config.h"
-#endif
#include <assert.h>
+#include <stdbool.h>
#include "iroptimize.h"
#include "obst.h"
#include "irnode_t.h"
#include "cdep.h"
#include "ircons.h"
-#include "irdom.h"
#include "irgmod.h"
#include "irgopt.h"
#include "irgwalk.h"
#include "irtools.h"
-#include "array.h"
-#include "xmalloc.h"
+#include "array_t.h"
+#include "irpass_t.h"
+#include "be.h"
-// debug
#include "irdump.h"
#include "debug.h"
-DEBUG_ONLY(firm_dbg_module_t *dbg);
-
-/** allow every Psi to be created. */
-static int default_allow_ifconv(ir_node *sel, ir_node* phi_list, int i, int j)
-{
- (void) sel;
- (void) phi_list;
- (void) i;
- (void) j;
- return 1;
-}
-
-/**
- * Default options.
- */
-static const opt_if_conv_info_t default_info = {
- 0, /* doesn't matter for Psi */
- default_allow_ifconv
-};
-
/**
- * Additional block info.
+ * Environment for if-conversion.
*/
-typedef struct block_info {
- ir_node *phi; /**< head of the Phi list */
- int has_pinned; /**< set if the block contains instructions that cannot be moved */
-} block_info;
-
-
-static INLINE block_info* get_block_blockinfo(const ir_node* block)
-{
- return get_irn_link(block);
-}
+typedef struct walker_env {
+ arch_allow_ifconv_func allow_ifconv;
+ bool changed; /**< Set if the graph was changed. */
+} walker_env;
+DEBUG_ONLY(static firm_dbg_module_t *dbg);
/**
* Returns non-zero if a Block can be emptied.
+ *
+ * @param block the block
*/
-static int can_empty_block(ir_node *block)
+static bool can_empty_block(ir_node *block)
{
- return !get_block_blockinfo(block)->has_pinned;
+ return get_Block_mark(block) == 0;
}
-
+/**
+ * Find the ProjX node leading from block dependency to block start.
+ *
+ * @param start a block that is control depended on dependency
+ * @param dependency the block that decides whether start is executed
+ *
+ * @return a ProjX node that represent the decision control flow or
+ * NULL is start is not dependent at all or a block on the way
+ * cannot be emptied
+ */
static ir_node* walk_to_projx(ir_node* start, const ir_node* dependency)
{
int arity;
arity = get_irn_arity(start);
for (i = 0; i < arity; ++i) {
ir_node* pred = get_irn_n(start, i);
- ir_node* pred_block = get_nodes_block(pred);
+ ir_node* pred_block = get_nodes_block(skip_Proj(pred));
if (pred_block == dependency) {
if (is_Proj(pred)) {
assert(get_irn_mode(pred) == mode_X);
+ /* we found it */
return pred;
}
+ /* Not a Proj? Should not happen. */
return NULL;
}
if (is_Proj(pred)) {
assert(get_irn_mode(pred) == mode_X);
+ /* another Proj but not from the control block */
return NULL;
}
/**
- * Copies the DAG starting at node to the ith predecessor block of src_block
- * -if the node isn't in the src_block, this is a nop and the node is returned
- * -if the node is a phi in the src_block, the ith predecessor of the phi is
- * returned
- * otherwise returns the copy of the passed node
+ * Recursively copies the DAG starting at node to the i-th predecessor
+ * block of src_block
+ * - if node isn't in the src_block, recursion ends and node is returned
+ * - if node is a Phi in the src_block, the i-th predecessor of this Phi is
+ * returned and recursion ends
+ * otherwise returns a copy of the passed node created in the i-th predecessor of
+ * src_block.
+ *
+ * @param node a root of a DAG
+ * @param src_block the block of the DAG
+ * @param i the position of the predecessor the DAG
+ * is moved to
+ *
+ * @return the root of the copied DAG
*/
static ir_node* copy_to(ir_node* node, ir_node* src_block, int i)
{
ir_node* dst_block;
ir_node* copy;
- int arity;
int j;
- if (get_nodes_block(node) != src_block) return node;
- if (get_irn_op(node) == op_Phi) return get_irn_n(node, i);
+ if (get_nodes_block(node) != src_block) {
+ /* already outside src_block, do not copy */
+ return node;
+ }
+ if (is_Phi(node)) {
+ /* move through the Phi to the i-th predecessor */
+ return get_irn_n(node, i);
+ }
+ /* else really need a copy */
copy = exact_copy(node);
dst_block = get_nodes_block(get_irn_n(src_block, i));
set_nodes_block(copy, dst_block);
DB((dbg, LEVEL_1, "Copying node %+F to block %+F, copy is %+F\n",
node, dst_block, copy));
- arity = get_irn_arity(node);
- for (j = 0; j < arity; ++j) {
+ /* move recursively all predecessors */
+ for (j = get_irn_arity(node) - 1; j >= 0; --j) {
set_irn_n(copy, j, copy_to(get_irn_n(node, j), src_block, i));
DB((dbg, LEVEL_2, "-- pred %d is %+F\n", j, get_irn_n(copy, j)));
}
/**
- * Remove predecessors i and j from node and add predecessor new_pred
+ * Remove predecessors i and j (i < j) from a node and
+ * add an additional predecessor new_pred.
+ *
+ * @param node the node whose inputs are changed
+ * @param i the first index to remove
+ * @param j the second index to remove
+ * @param new_pred a node that is added as a new input to node
*/
static void rewire(ir_node* node, int i, int j, ir_node* new_pred)
{
/**
- * Remove the jth predecessors from the ith predecessor of block and add it to block
+ * Remove the j-th predecessors from the i-th predecessor of block and add it to block
*/
static void split_block(ir_node* block, int i, int j)
{
ir_node* pred_block = get_nodes_block(get_irn_n(block, i));
int arity = get_irn_arity(block);
int new_pred_arity;
- ir_node* phi;
+ ir_node *phi, *next;
ir_node **ins;
ir_node **pred_ins;
int k;
NEW_ARR_A(ir_node*, ins, arity + 1);
- for (phi = get_block_blockinfo(block)->phi; phi != NULL; phi = get_irn_link(phi)) {
+ for (phi = get_Block_phis(block); phi != NULL; phi = get_Phi_next(phi)) {
ir_node* copy = copy_to(get_irn_n(phi, i), pred_block, j);
for (k = 0; k < i; ++k) ins[k] = get_irn_n(phi, k);
new_pred_arity = get_irn_arity(pred_block) - 1;
NEW_ARR_A(ir_node*, pred_ins, new_pred_arity);
- for (phi = get_block_blockinfo(pred_block)->phi; phi != NULL; phi = get_irn_link(phi)) {
+ for (phi = get_Block_phis(pred_block); phi != NULL; phi = next) {
for (k = 0; k < j; ++k) pred_ins[k] = get_irn_n(phi, k);
for (; k < new_pred_arity; ++k) pred_ins[k] = get_irn_n(phi, k + 1);
assert(k == new_pred_arity);
+ next = get_Phi_next(phi);
if (new_pred_arity > 1) {
set_irn_in(phi, new_pred_arity, pred_ins);
} else {
}
}
-
-static void if_conv_walker(ir_node* block, void* env)
+/**
+ * Block walker: Search for diamonds and do the if conversion.
+ */
+static void if_conv_walker(ir_node *block, void *ctx)
{
- opt_if_conv_info_t* opt_info = env;
+ walker_env *env = ctx;
int arity;
int i;
/* Bail out, if there are no Phis at all */
- if (get_block_blockinfo(block)->phi == NULL) return;
+ if (get_Block_phis(block) == NULL) return;
restart:
arity = get_irn_arity(block);
for (i = 0; i < arity; ++i) {
ir_node* pred0;
- cdep* cdep;
+ ir_cdep* cdep;
- pred0 = get_nodes_block(get_irn_n(block, i));
+ pred0 = get_Block_cfgpred_block(block, i);
for (cdep = find_cdep(pred0); cdep != NULL; cdep = cdep->next) {
const ir_node* dependency = cdep->node;
ir_node* projx0 = walk_to_projx(pred0, dependency);
if (projx0 == NULL) continue;
cond = get_Proj_pred(projx0);
- if (get_irn_op(cond) != op_Cond) continue;
+ if (! is_Cond(cond))
+ continue;
/* We only handle boolean decisions, no switches */
if (get_irn_mode(get_Cond_selector(cond)) != mode_b) continue;
for (j = i + 1; j < arity; ++j) {
ir_node* projx1;
- ir_node* conds[1];
- ir_node* psi_block;
+ ir_node* sel;
+ ir_node* mux_block;
ir_node* phi;
+ ir_node* p;
ir_node* pred1;
+ bool supported;
+ bool negated;
+ dbg_info* cond_dbg;
- pred1 = get_nodes_block(get_irn_n(block, j));
+ pred1 = get_Block_cfgpred_block(block, j);
if (!is_cdep_on(pred1, dependency)) continue;
if (projx1 == NULL) continue;
- phi = get_block_blockinfo(block)->phi;
- if (!opt_info->allow_ifconv(get_Cond_selector(cond), phi, i, j)) continue;
+ sel = get_Cond_selector(cond);
+ phi = get_Block_phis(block);
+ supported = true;
+ negated = get_Proj_proj(projx0) == pn_Cond_false;
+ for (p = phi; p != NULL; p = get_Phi_next(p)) {
+ ir_node *mux_false;
+ ir_node *mux_true;
+ if (negated) {
+ mux_true = get_Phi_pred(p, j);
+ mux_false = get_Phi_pred(p, i);
+ } else {
+ mux_true = get_Phi_pred(p, i);
+ mux_false = get_Phi_pred(p, j);
+ }
+ if (!env->allow_ifconv(sel, mux_false, mux_true)) {
+ supported = false;
+ break;
+ }
+ }
+ if (!supported)
+ continue;
DB((dbg, LEVEL_1, "Found Cond %+F with proj %+F and %+F\n",
cond, projx0, projx1
));
+ env->changed = true;
prepare_path(block, i, dependency);
prepare_path(block, j, dependency);
arity = get_irn_arity(block);
- conds[0] = get_Cond_selector(cond);
-
- psi_block = get_nodes_block(cond);
+ mux_block = get_nodes_block(cond);
+ cond_dbg = get_irn_dbg_info(cond);
do {
ir_node* val_i = get_irn_n(phi, i);
ir_node* val_j = get_irn_n(phi, j);
- ir_node* psi;
+ ir_node* mux;
ir_node* next_phi;
if (val_i == val_j) {
- psi = val_i;
- DB((dbg, LEVEL_2, "Generating no psi, because both values are equal\n"));
+ mux = val_i;
+ DB((dbg, LEVEL_2, "Generating no Mux, because both values are equal\n"));
} else {
- ir_node* vals[2];
+ ir_node *t, *f;
/* Something is very fishy if two predecessors of a PhiM point into
* one block, but not at the same memory node
*/
assert(get_irn_mode(phi) != mode_M);
- if (get_Proj_proj(projx0) == pn_Cond_true) {
- vals[0] = val_i;
- vals[1] = val_j;
+ if (negated) {
+ t = val_j;
+ f = val_i;
} else {
- vals[0] = val_j;
- vals[1] = val_i;
+ t = val_i;
+ f = val_j;
}
- psi = new_r_Psi(
- current_ir_graph, psi_block, 1, conds, vals, get_irn_mode(phi)
- );
- DB((dbg, LEVEL_2, "Generating %+F for %+F\n", psi, phi));
+ mux = new_rd_Mux(cond_dbg, mux_block, sel, f, t, get_irn_mode(phi));
+ DB((dbg, LEVEL_2, "Generating %+F for %+F\n", mux, phi));
}
- next_phi = get_irn_link(phi);
+ next_phi = get_Phi_next(phi);
if (arity == 2) {
- exchange(phi, psi);
+ exchange(phi, mux);
} else {
- rewire(phi, i, j, psi);
+ rewire(phi, i, j, mux);
}
-
phi = next_phi;
} while (phi != NULL);
- exchange(get_nodes_block(get_irn_n(block, i)), psi_block);
- exchange(get_nodes_block(get_irn_n(block, j)), psi_block);
+ exchange(get_nodes_block(get_irn_n(block, i)), mux_block);
+ exchange(get_nodes_block(get_irn_n(block, j)), mux_block);
if (arity == 2) {
+ unsigned mark;
#if 1
- DB((dbg, LEVEL_1, "Welding block %+F and %+F\n", block, psi_block));
- /* copy the block-info from the Psi-block to the block before merging */
- get_block_blockinfo(psi_block)->has_pinned |= get_block_blockinfo(block)->has_pinned;
- set_irn_link(block, get_irn_link(psi_block));
-
- set_irn_in(block, get_irn_arity(psi_block), get_irn_in(psi_block) + 1);
- exchange_cdep(psi_block, block);
- exchange(psi_block, block);
+ DB((dbg, LEVEL_1, "Welding block %+F and %+F\n", block, mux_block));
+ /* copy the block-info from the Mux-block to the block before merging */
+
+ mark = get_Block_mark(mux_block) | get_Block_mark(block);
+ set_Block_mark(block, mark);
+ set_Block_phis(block, get_Block_phis(mux_block));
+
+ set_irn_in(block, get_irn_arity(mux_block), get_irn_in(mux_block) + 1);
+ exchange_cdep(mux_block, block);
+ exchange(mux_block, block);
#else
- DB((dbg, LEVEL_1, "Welding block %+F to %+F\n", block, psi_block));
- get_block_blockinfo(psi_block)->has_pinned |= get_block_blockinfo(block)->has_pinned;
- exchange(block, psi_block);
+ DB((dbg, LEVEL_1, "Welding block %+F to %+F\n", block, mux_block));
+ mark = get_Block_mark(mux_block) | get_Block_mark(block);
+ /* mark both block just to be sure, should be enough to mark mux_block */
+ set_Block_mark(mux_block, mark);
+ exchange(block, mux_block);
#endif
return;
} else {
- rewire(block, i, j, new_r_Jmp(current_ir_graph, psi_block));
+ rewire(block, i, j, new_r_Jmp(mux_block));
goto restart;
}
}
}
/**
- * Block walker: add additional data
+ * Block walker: clear block marks and Phi lists.
*/
static void init_block_link(ir_node *block, void *env)
{
- struct obstack *obst = env;
- block_info *bi = obstack_alloc(obst, sizeof(*bi));
-
- bi->phi = NULL;
- bi->has_pinned = 0;
- set_irn_link(block, bi);
+ (void)env;
+ set_Block_mark(block, 0);
+ set_Block_phis(block, NULL);
}
/**
- * Daisy-chain all phis in a block
- * If a non-movable node is encountered set the has_pinned flag
+ * Daisy-chain all Phis in a block.
+ * If a non-movable node is encountered set the has_pinned flag in its block.
*/
static void collect_phis(ir_node *node, void *env)
{
if (is_Phi(node)) {
ir_node *block = get_nodes_block(node);
- block_info *bi = get_block_blockinfo(block);
- set_irn_link(node, bi->phi);
- bi->phi = node;
+ add_Block_phi(block, node);
} else {
- if (is_no_Block(node) && get_irn_pinned(node) == op_pin_state_pinned) {
+ if (!is_Block(node) && get_irn_pinned(node) == op_pin_state_pinned) {
/*
- * Ignore control flow nodes, these will be removed.
- * This ignores Raise. That is surely bad. FIXME.
+ * Ignore control flow nodes (except Raise), these will be removed.
*/
- if (!is_cfop(node)) {
+ if (!is_cfop(node) && !is_Raise(node)) {
ir_node *block = get_nodes_block(node);
- block_info *bi = get_block_blockinfo(block);
DB((dbg, LEVEL_2, "Node %+F in block %+F is unmovable\n", node, block));
- bi->has_pinned = 1;
+ set_Block_mark(block, 1);
}
}
}
}
-
-/*
- * Transform multiple cascaded Psis into one Psi
- */
-static ir_node* fold_psi(ir_node* psi)
+void opt_if_conv(ir_graph *irg)
{
- int arity = get_Psi_n_conds(psi);
- int new_arity = 0;
- int i;
- ir_node* n;
- ir_node** conds;
- ir_node** vals;
- int j;
- ir_node* new_psi;
-
- for (i = 0; i < arity; ++i) {
- n = get_Psi_val(psi, i);
- if (get_irn_op(n) == op_Psi) {
- new_arity += get_Psi_n_conds(n) + 1;
- } else {
- ++new_arity;
- }
- }
- n = get_Psi_default(psi);
- if (get_irn_op(n) == op_Psi) {
- new_arity += get_Psi_n_conds(n);
- }
-
- if (arity == new_arity) return psi; // no attached Psis found
- DB((dbg, LEVEL_1, "Folding %+F from %d to %d conds\n", psi, arity, new_arity));
-
- NEW_ARR_A(ir_node *, conds, new_arity);
- NEW_ARR_A(ir_node *, vals, new_arity + 1);
- j = 0;
- for (i = 0; i < arity; ++i) {
- ir_node* c = get_Psi_cond(psi, i);
-
- n = get_Psi_val(psi, i);
- if (get_irn_op(n) == op_Psi) {
- int a = get_Psi_n_conds(n);
- int k;
-
- for (k = 0; k < a; ++k) {
- conds[j] = new_r_And(
- current_ir_graph, get_nodes_block(psi),
- c, get_Psi_cond(n, k), mode_b
- );
- vals[j] = get_Psi_val(n, k);
- ++j;
- }
- conds[j] = c;
- vals[j] = get_Psi_default(n);
- } else {
- conds[j] = c;
- vals[j] = n;
- }
- ++j;
- }
- n = get_Psi_default(psi);
- if (get_irn_op(n) == op_Psi) {
- int a = get_Psi_n_conds(n);
- int k;
-
- for (k = 0; k < a; ++k) {
- conds[j] = get_Psi_cond(n, k);
- vals[j] = get_Psi_val(n, k);
- ++j;
- }
- vals[j] = get_Psi_default(n);
- } else {
- vals[j] = n;
- }
- assert(j == new_arity);
- new_psi = new_r_Psi(
- current_ir_graph, get_nodes_block(psi),
- new_arity, conds, vals, get_irn_mode(psi)
- );
- DB((dbg, LEVEL_1, "Folded %+F into new %+F\n", psi, new_psi));
- exchange(psi, new_psi);
- return new_psi;
-}
-
-
-/*
- * Merge consecutive psi inputs if the data inputs are the same
- */
-static ir_node* meld_psi(ir_node* psi)
-{
- int arity = get_Psi_n_conds(psi);
- int new_arity;
- ir_node** conds;
- ir_node** vals;
- ir_node* cond;
- ir_node* val;
- int i;
- int j;
- ir_node* new_psi;
-
- new_arity = 1;
- val = get_Psi_val(psi, 0);
- DB((dbg, LEVEL_1, "Pred 0 of %+F is %+F\n", psi, val));
- for (i = 1; i < arity; ++i) {
- ir_node* v = get_Psi_val(psi, i);
- DB((dbg, LEVEL_1, "Pred %2d of %+F is %+F\n", i, psi, v));
- if (val != v) {
- val = v;
- ++new_arity;
- }
- }
- DB((dbg, LEVEL_1, "Default of %+F is %+F\n", psi, get_Psi_default(psi)));
- if (val == get_Psi_default(psi)) --new_arity;
-
- DB((dbg, LEVEL_1, "Melding Psi %+F from %d conds to %d\n", psi, arity, new_arity));
-
- if (new_arity == arity) return psi;
-
- /* If all data inputs of the Psi are equal, exchange the Psi with that value */
- if (new_arity == 0) {
- exchange(psi, val);
- return val;
- }
-
- NEW_ARR_A(ir_node *, conds, new_arity);
- NEW_ARR_A(ir_node *, vals, new_arity + 1);
- cond = get_Psi_cond(psi, 0);
- val = get_Psi_val(psi, 0);
- j = 0;
- for (i = 1; i < arity; ++i) {
- ir_node* v = get_Psi_val(psi, i);
-
- if (v == val) {
- cond = new_r_Or(
- current_ir_graph, get_nodes_block(psi),
- cond, get_Psi_cond(psi, i), mode_b
- );
- } else {
- conds[j] = cond;
- vals[j] = val;
- ++j;
- val = v;
- }
- }
- if (val != get_Psi_default(psi)) {
- conds[j] = cond;
- vals[j] = val;
- ++j;
- }
- vals[j] = get_Psi_default(psi);
- assert(j == new_arity);
- new_psi = new_r_Psi(
- current_ir_graph, get_nodes_block(psi),
- new_arity, conds, vals, get_irn_mode(psi)
- );
- DB((dbg, LEVEL_1, "Molded %+F into %+F\n", psi, new_psi));
- exchange(psi, new_psi);
- return new_psi;
-}
-
-
-/**
- * Split a Psi with multiple conditions into multiple Psis with one condtition
- * each
- */
-static ir_node* split_psi(ir_node* psi)
-{
- int arity = get_Psi_n_conds(psi);
- ir_mode* mode;
- ir_node* block;
- ir_node* rval;
- int i;
-
- if (arity == 1) return psi;
-
- mode = get_irn_mode(psi);
- block = get_nodes_block(psi);
- rval = get_Psi_default(psi);
- for (i = arity - 1; i >= 0; --i) {
- ir_node* conds[1];
- ir_node* vals[2];
-
- conds[0] = get_Psi_cond(psi, i);
- vals[0] = get_Psi_val(psi, i);
- vals[1] = rval;
- rval = new_r_Psi(
- current_ir_graph, block, 1, conds, vals, mode
- );
- }
- exchange(psi, rval);
- return rval;
-}
-
-
-static void optimise_psis(ir_node* node, void* env)
-{
- (void) env;
-
- if (get_irn_op(node) != op_Psi) return;
-#if 1
- node = fold_psi(node);
-#endif
-#if 1
- node = meld_psi(node);
-#endif
-#if 1
- node = split_psi(node);
-#endif
-}
-
-
-void opt_if_conv(ir_graph *irg, const opt_if_conv_info_t *params)
-{
- struct obstack obst;
- opt_if_conv_info_t p;
-
- if (! get_opt_if_conversion())
- return;
+ walker_env env;
+ const backend_params *be_params = be_get_backend_param();
/* get the parameters */
- p = (params != NULL ? *params : default_info);
+ env.allow_ifconv = be_params->allow_ifconv;
+ env.changed = false;
FIRM_DBG_REGISTER(dbg, "firm.opt.ifconv");
remove_critical_cf_edges(irg);
compute_cdep(irg);
- assure_doms(irg);
- obstack_init(&obst);
- irg_block_walk_graph(irg, init_block_link, NULL, &obst);
+ ir_reserve_resources(irg, IR_RESOURCE_BLOCK_MARK | IR_RESOURCE_PHI_LIST);
+
+ irg_block_walk_graph(irg, init_block_link, NULL, NULL);
irg_walk_graph(irg, collect_phis, NULL, NULL);
- irg_block_walk_graph(irg, NULL, if_conv_walker, &p);
+ irg_block_walk_graph(irg, NULL, if_conv_walker, &env);
- local_optimize_graph(irg);
+ ir_free_resources(irg, IR_RESOURCE_BLOCK_MARK | IR_RESOURCE_PHI_LIST);
- irg_walk_graph(irg, NULL, optimise_psis, NULL);
+ if (env.changed) {
+ local_optimize_graph(irg);
- obstack_free(&obst, NULL);
+ /* graph has changed, invalidate analysis info */
+ set_irg_outs_inconsistent(irg);
+ set_irg_extblk_inconsistent(irg);
+ set_irg_loopinfo_inconsistent(irg);
+ set_irg_doms_inconsistent(irg);
+ }
- free_dom(irg);
free_cdep(irg);
}
+
+ir_graph_pass_t *opt_if_conv_pass(const char *name)
+{
+ return def_graph_pass(name ? name : "ifconv", opt_if_conv);
+}
projects / libfirm / blobdiff