#include <stdlib.h>
+#include "obst.h"
+#include "pset.h"
+#include "bitset.h"
#include "debug.h"
-#include "bechordal.h"
+#include "bechordal.h"
+#include "belive.h"
#include "bera_t.h"
#include "bephicongr_t.h"
#include "bephicoal_t.h"
+#define DEBUG_LVL 1
-static firm_dbg_module_t *dbgmod = NULL;
+#define MAX_PHI_CLS_SIZE (1<<(sizeof(unsigned char)*8)) /* possible colors added should fit into unsigned char */
+#define MAX_COLORS 32
+#define CHANGE_IMPOSSIBLE -1
+#define CHANGE_SAVE 1
+#define DRYRUN 1
+#define PERFORM 0
-void be_phi_coal_init(void) {
- dbgmod = firm_dbg_register("Phi coalescing");
- firm_dbg_set_mask(dbgmod, 1);
- DBG((dbgmod, 1, "Phi coalescing dbg enabled"));
-}
+typedef struct _phi_unit_t {
+ unsigned char count;
+ unsigned char phi_count;
+ /* 1 phi */
+ ir_node **members; /**< [0] is the phi node. [1..count-1] the arguments of the phi not interfering with it */
+ int *colors; /**< [i] is the color to set for members[i]. [i] == NO_COLOR means dont change anything for members[i]*/
+ char *is_live_in; /**< [i]==1 means members[i] is live-in in (all of) its cf-pred-blocks of the phi node */
+ int size; /**< size of the max independent set of members. The set is markes by colors[i] != NO_COLOR */
+ int changes; /**< number of re-assigned nodes belonging to phi-classes */
+} phi_unit_t;
-static INLINE ir_node **pset_to_array(pset *theset) {
- ir_node **res, *p;
- int i, count;
- count = pset_count(theset);
- res = (ir_node **) malloc(count * sizeof(ir_node*));
- for (i = 0, p = (ir_node *)pset_first(theset); p; p = (ir_node *)pset_next(theset))
- res[i++] = p;
- assert(i == count);
+static firm_dbg_module_t *dbgphi = NULL;
- return res;
-}
+/**
+ * Contains ir_nodes of phi-classes whose colors were reassigned during coalescing.
+ * So one can check not to switch them twice or more.
+ */
+static pset *pinned_nodes = NULL;
+/**
+ * Contains ir_nodes of phi-classes whose colors may change unlimited times.
+ * These nodes are not optimizable, so there is no need to pin their color.
+ */
+static pset *free_nodes = NULL;
-static INLINE pset *clone(pset *theset) {
- void *p;
- pset *res;
- res = pset_new_ptr(8);
- for (p = pset_first(theset); p; p = pset_next(theset))
- pset_insert_ptr(res, p);
-
- return res;
-}
+/* TODO: ask/check if additional ir_node-space is initialized with 0000 */
+#define belongs_to_a_phi_class(n) (get_irn_phi_info(n)->phi)
+#define is_color_free(bl,col) (!bitset_is_set(get_ra_block_info(bl)->used_colors, col))
-static void coalesce_locals(pset *phi_class, dominfo_t *dominfo) {
- int i, count, phi_count, arity, intf_det, phi_col, allfree;
- pset *pc, *intffree;
- ir_node *phi, *n, *m;
-// ir_node **members;
+/**
+ * Set the color of node @p n to @p col, but acts
+ * pinning aware.
+ */
+static INLINE void set_color(ir_node *n, int col) {
+ assert(!pset_find_ptr(pinned_nodes, n));
+ set_irn_color(n, col);
+ if (belongs_to_a_phi_class(n) && !pset_find_ptr(free_nodes, n))
+ pset_insert_ptr(pinned_nodes, n);
+}
- count = pset_count(phi_class);
- pc = clone(phi_class);
-// members = pset_to_array(phi_class);
+/**
+ * Tries to set the color of @p n to @p col.
+ * @param n The node to set the color for
+ * @param col The color to set.
+ * @param dryrun If true no colors are actually set, only testing is performed.
+ * If false colors get set and it must be sure that no conflicts will occur.
+ * @return If setting the color is impossible CHANGE_IMPOSSIBLE is returned
+ * else the number of nodes that need a (cascading) change is returned.
+ */
+static int color_irn(ir_node *n, int col, int dryrun) {
+ ir_node *bl;
+ int res = 0;
+ DBG((dbgphi, 1, "\t\t\t\t%n %d\n", n, col));
+ assert(is_color(col));
+
+ if (get_irn_color(n) == col) {
+ DBG((dbgphi, 1, "\t\t\t\t\tSame\n"));
+ return 0;
+ }
- /* how many phi nodes are in this class? */
- DBG((dbgmod, 1, "Checking phi count\n"));
- phi_count = 0;
- for (n = (ir_node *)pset_first(pc); n; n = (ir_node *)pset_next(pc)) {
- if (is_Phi(n)) {
- phi = n;
- phi_count++;
- }
+ if (pset_find_ptr(pinned_nodes, n)) {
+ DBG((dbgphi, 1, "\t\t\t\t\tPinned\n"));
+ if (!dryrun)
+ assert(0 && "No prior check with dryrun=1 or buggy");
+ return CHANGE_IMPOSSIBLE;
}
- if (phi_count > 1) {
- DBG((dbgmod, 1, "Dropped: Too many phis\n"));
- goto exit;
+ bl = get_nodes_block(n);
+ if (is_color_free(bl, col) && !is_live_out(bl, n)) {
+ DBG((dbgphi, 1, "\t\t\t\t\tFree\n"));
+ if (!dryrun)
+ set_color(n, col);
+ return 1;
}
- assert(phi_count == 1 && phi);
+ /* for now, in the aldi-version return impossible */
+ DBG((dbgphi, 1, "\t\t\t\t\tImpossible\n"));
+ return CHANGE_IMPOSSIBLE;
- /* where is the definition of the arguments? */
- DBG((dbgmod, 1, "Checking arg def\n"));
- arity = get_irn_arity(phi);
- for (i = 0; i < arity; ++i) {
- ir_node *block_of_arg, *block_ith_pred;
- ir_node *arg = get_irn_n(phi, i);
+ return res;
+}
- /* TODO: check next few lines after const node copy placement */
-// if (iro_Const == get_irn_opcode(arg) && CONSTS_SPLIT_PHI_CLASSES)
-// continue;
- block_of_arg = get_nodes_block(arg);
- block_ith_pred = get_nodes_block(get_irn_n(get_nodes_block(phi), i));
+/**
+ * Tries to set as much members of a phi unit as possible to color @p col.
+ */
+static void try_colors(phi_unit_t *pu, int col, int b_size, int b_changes) {
+ struct obstack ob;
+ int i, o, cand_size, mis_size, changes;
+ ir_node **cand, **mis;
+
+ cand_size = 0;
+ obstack_init(&ob);
+
+ /* first init pessimistically, so we can just return
+ * if we see there wont be a better result */
+ pu->size = 0;
+ for (i = 0; i < pu->count; ++i)
+ pu->colors[i] = NO_COLOR;
+
+ /* For all members check if color would be possible.
+ * Does not check if color is possible in combination with
+ * other members colors being set */
+ changes = 0;
+ for (i = 0; i < pu->count; ++i) {
+ int tmp_changes = color_irn(pu->members[i], col, DRYRUN);
+ if (tmp_changes != CHANGE_IMPOSSIBLE) {
+ DBG((dbgphi, 1, "\t\t\tAdding to cand %n\n", pu->members[i]));
+ obstack_ptr_grow(&ob, pu->members[i]);
+ cand_size++;
+ changes += tmp_changes;
+ }
+ /* if color is not possible for the phi node then exit (phi comes first)*/
+ if (cand_size == 0)
+ goto ret;
+ }
+ cand = obstack_finish(&ob);
+
+ /* shortcut: if cand is worse than best the mis wont be better. */
+ if (cand_size < b_size || (cand_size == b_size && changes >= b_changes))
+ goto ret;
+
+ /* now take the candidates cand and determine a max independent set
+ * with respect to edges representing live range interference */
+ /* TODO: make this 'un-greedy' */
+ mis_size = 0;
+ for (i = 0; i < cand_size; ++i) {
+ int intf_det = 0;
+ for (o = 0; o < mis_size; ++o) {
+ mis = (ir_node**) obstack_base(&ob);
+ if (values_interfere(cand[i], mis[o])) {
+ intf_det = 1;
+ break;
+ }
+ }
- if (block_of_arg != block_ith_pred) {
- DBG((dbgmod, 1, "Dropped: Arg-def not in pred-block\n"));
- goto exit;
+ if (!intf_det) {
+ DBG((dbgphi, 1, "\t\t\tAdding to mis %n\n", cand[i]));
+ obstack_ptr_grow(&ob, cand[i]);
+ mis_size++;
}
}
+ mis = obstack_finish(&ob);
+
+ /* Now set the colors of all nodes in the mis to col.
+ * - Each change taken alone is conflict free.
+ * - If all members are not live-in in their cf-pred-blocks there will be no
+ * conflict applying all changes
+ * - If there is a member, which is live-in in its cf-pred-block of the phi
+ * node, it is possible that all changes together will conflict.
+ */
+ for (i = 0; i < pu->count; ++i)
+ for (o = 0; o < mis_size; ++o)
+ if (pu->members[i] == mis[o] && get_irn_color(pu->members[i]) != col)
+ pu->colors[i] = col;
+ret:
+ obstack_free(&ob, NULL);
+}
- /* determine a greedy set of non-interfering members
- * crucial: starting with the phi node
- */
- DBG((dbgmod, 1, "Building greedy non-interfering set\n"));
- intffree = pset_new_ptr(4);
-
- pset_remove_ptr(pc, phi);
- pset_insert_ptr(intffree, phi);
-
- while (m = (ir_node *)pset_first(pc), m) {
- DBG((dbgmod, 1, "Checking %n\n", m));
- pset_break(pc);
- pset_remove_ptr(pc, m);
-
- intf_det = 0;
- for (n = (ir_node *)pset_first(intffree); n; n = (ir_node *)pset_next(intffree)) {
- DBG((dbgmod, 1, "\t%n", n));
- if (phi_ops_interfere(m, n)) {
- DBG((dbgmod, 1, "\tinterf\n"));
- intf_det = 1;
+
+/**
+ * Sets the colors of members[i] to colors[i] as far as possible.
+ * Each single change must be conflict free (checked by try_colors).
+ * In some cases not all colors can be set.
+ */
+static void set_colors(phi_unit_t *pu) {
+ int i;
+ int change_is_save, live_in_occured = 0;
+
+ for (i = 0; i < pu->count; ++i)
+ if (pu->colors[i] != NO_COLOR) {
+ if (pu->is_live_in[i])
+ live_in_occured = 1;
+
+ change_is_save = CHANGE_SAVE;
+ if (live_in_occured)
+ change_is_save = color_irn(pu->members[i], pu->colors[i], DRYRUN);
+
+ /* HINT: Dont change to == CHANGE_SAVE */
+ if (change_is_save != CHANGE_IMPOSSIBLE) {
+ DBG((dbgphi, 1, "\t\tSetting %n to %d\n", pu->members[i], pu->colors[i]));
+ color_irn(pu->members[i], pu->colors[i], PERFORM);
} else {
- DBG((dbgmod, 1, "\tclean\n"));
+ DBG((dbgphi, 1, "\t\tConflict due to a live-in: %n\n", pu->members[i]));
}
}
+}
- if (!intf_det) {
- DBG((dbgmod, 1, "Added to set\n"));
- pset_insert_ptr(intffree, m);
+
+/**
+ * Tries to re-allocate colors of this phi-class, to achieve a lower number of
+ * copies placed during phi destruction. Optimized version. Works only for
+ * phi-classes/phi-units with exactly 1 phi node, which is the case for approx.
+ * 80%.
+ */
+static void coalesce_1_phi(phi_unit_t *pu) {
+ int *b_colors, b_size, b_changes, b_color;
+ int i, col;
+
+ /* init best search result */
+ b_colors = malloc(pu->count * sizeof(*b_colors));
+ for (i = 0; i < pu->count; ++i)
+ b_colors[i] = NO_COLOR;
+ b_size = 0;
+ b_changes = 0;
+ b_color = NO_COLOR;
+
+ /* find optimum of all colors */
+ for (col = MAX_COLORS-1; col >= 0; --col) {
+ DBG((dbgphi, 1, "\tTrying color %d\n", col));
+ try_colors(pu, col, b_size, b_changes);
+
+ /* did we find a better max ind. set? */
+ if (pu->size > b_size || (pu->size == b_size && pu->changes < b_changes)) {
+ b_size = pu->size;
+ b_changes = pu->changes;
+ b_color = col;
+ memcpy(b_colors, pu->colors, pu->count * sizeof(*b_colors));
+ DBG((dbgphi, 1, "\t\tBetter! Size: %d Changes: %d\n", b_size, b_changes));
}
- }
- /*
- * color the non interfering set
- */
- DBG((dbgmod, 1, "Coloring...\n"));
- phi_col = get_irn_color(phi);
- DBG((dbgmod, 1, "phi-color: %d\n", grnfxt));
-
- /* check if phi color is free in blocks of all members */
- allfree = 1;
- for (n = (ir_node *)pset_first(intffree); n; n = (ir_node *)pset_next(intffree)) {
- ir_node *block;
- if (n == phi)
- continue;
-
- block = get_nodes_block(n);
-/* TODO
- if (! COLORFREE(block, phi_col)) {
- allfree = 0;
+ /* shortcut: if all members can be colored we are content and doubt that
+ * reducing b_changes justifies all the further trying. */
+ if (b_size == pu->count)
break;
+ }
+
+ /* now apply the found optimum */
+ DBG((dbgphi, 1, "\tBest color: %d Copies: %d/%d Changes: %d\n", b_color, pu->count-b_size, pu->count, b_changes));
+ pu->size = b_size;
+ pu->changes = b_changes;
+ memcpy(pu->colors, b_colors, pu->count * sizeof(*b_colors));
+ set_colors(pu);
+
+ free(b_colors);
+}
+
+/**
+ * Tries to re-allocate colors of this phi-class, to achieve a lower number of
+ * copies placed during phi destruction. General purpose version.
+ */
+static void coalesce_n_phi(phi_unit_t *pu) {
+ DBG((dbgphi, 1, "\n"));
+ /* TODO */
+}
+
+/**
+ * Prepare a phi class for further processing as a phi unit.
+ */
+static phi_unit_t *new_phi_unit(pset *pc) {
+ phi_unit_t *pu;
+ ir_node *n, *phi = NULL;
+
+ assert(pset_count(pc) <= MAX_PHI_CLS_SIZE && "Phi class too large!");
+
+ pu = malloc(sizeof(*pu));
+ pu->phi_count = 0;
+ for (n = pset_first(pc); n; n = pset_next(pc))
+ if (is_Phi(n)) {
+ phi = n;
+ pu->phi_count++;
}
-*/
+
+ if (pu->phi_count == 1) {
+ ir_node **tmp, *phi_block;
+ int i, max;
+ struct obstack ob;
+
+ obstack_init(&ob);
+
+ /* build member set not containing phi interferers */
+ DBG((dbgphi, 1, "Phi-1 class:\n"));
+ pu->count = 1; /*for the phi*/
+ for (n = pset_first(pc); n; n = pset_next(pc)) {
+ if (!is_Phi(n) && !values_interfere(phi, n)) {
+ DBG((dbgphi, 1, "\tAdding to members: %n\n", n));
+ obstack_ptr_grow(&ob, n);
+ pu->count++;
+ } else {
+ DBG((dbgphi, 1, "\tPhi interferer: %n\n", n));
+ pset_insert_ptr(free_nodes, n);
+ }
+ }
+ tmp = obstack_finish(&ob);
+ pu->members = malloc(pu->count * sizeof(*pu->members));
+ pu->members[0] = phi;
+ memcpy(&pu->members[1], tmp, (pu->count-1) * sizeof(*tmp));
+
+ /* init of colors array */
+ pu->colors = malloc(pu->count * sizeof(*pu->colors));
+
+ /* live-in analysis */
+ /* HINT: It is possible that a node occurs twice as arg of a phi,
+ * one time being live-in, and another time not being live-in.
+ */
+ pu->is_live_in = calloc(pu->count, sizeof(*pu->is_live_in));
+ phi_block = get_nodes_block(phi);
+ for (i = 0, max = get_irn_arity(phi); i < max; ++i) {
+ int midx, o;
+ ir_node *arg, *block_ith_pred;
+
+ arg = get_irn_n(phi, i);
+ block_ith_pred = get_nodes_block(get_irn_n(phi_block, i));
+
+ /* find the arg in the members array */
+ midx = -1;
+ for (o = 0; o < pu->count; ++o)
+ if (pu->members[o] == arg) {
+ midx = o;
+ break;
+ }
+ if (midx == -1)
+ continue;
+
+ if (is_live_in(block_ith_pred, arg)) {
+ pu->is_live_in[midx] |= 1;
+ DBG((dbgphi, 1, "\t%n is live-in in %n\n", arg, block_ith_pred));
+ }
+ }
+
+ obstack_free(&ob, NULL);
+ } else {
+ DBG((dbgphi, 1, "Phi-n class:\n"));
+ /* TODO */
}
-/*
- if (allfree) {
- for (n = (ir_node *)pset_first(intffree); n; n = (ir_node *)pset_next(intffree))
- set_irn_color(n, phi_col);
+
+ DBG((dbgphi, 1, "\n"));
+ return pu;
+}
+
+/**
+ * Deletes a phi unit
+ */
+static void free_phi_unit(phi_unit_t *pu) {
+ DBG((dbgphi, 1, "\n"));
+ if (pu->phi_count == 1) {
+ free(pu->members);
+ free(pu->colors);
+ free(pu->is_live_in);
} else {
+ /* TODO */
+ }
+ free(pu);
+}
+
+void be_phi_coalesce(pset *all_phi_classes) {
+ pset *pc;
+
+ pinned_nodes = pset_new_ptr(256);
+ free_nodes = pset_new_ptr(64);
+
+ for (pc = pset_first(all_phi_classes); pc; pc = pset_next(all_phi_classes)) {
+ phi_unit_t *pu = new_phi_unit(pc);
+ if (pu->phi_count == 1)
+ coalesce_1_phi(pu);
+ else
+ coalesce_n_phi(pu);
+ free_phi_unit(pu);
}
-*/
-exit:
- del_pset(pc);
-// free(members);
+ del_pset(free_nodes);
+ del_pset(pinned_nodes);
}
-void be_phi_coalesce_locals(pset *all_phi_classes, dominfo_t *dominfo) {
- pset *phi_class;
-
- for (phi_class = (pset *)pset_first(all_phi_classes); phi_class; phi_class = (pset *)pset_next(all_phi_classes))
- coalesce_locals(phi_class, dominfo);
+void be_phi_coal_init(void) {
+ dbgphi = firm_dbg_register("Phi coalescing");
+ firm_dbg_set_mask(dbgphi, DEBUG_LVL);
}
projects / libfirm / blobdiff