#include "config.h"
#endif
+#include <stdlib.h>
+
+#include "ircons.h"
+#include "debug.h"
+
#include "bearch.h"
#include "belower.h"
#include "benode_t.h"
#include "bechordal_t.h"
-#include "besched.h"
+#include "besched_t.h"
#include "irgmod.h"
-#include "iredges.h"
+#include "iredges_t.h"
#include "irgwalk.h"
+#ifdef HAVE_MALLOC_H
+ #include <malloc.h>
+#endif
+#ifdef HAVE_ALLOCA_H
+ #include <alloca.h>
+#endif
+
#undef is_Perm
#define is_Perm(arch_env, irn) (arch_irn_classify(arch_env, irn) == arch_irn_class_perm)
+#undef is_Call
+#define is_Call(arch_env, irn) (arch_irn_classify(arch_env, irn) == arch_irn_class_call)
+
/* lowering walker environment */
typedef struct _lower_env_t {
- be_chordal_env_t *chord_env;
- int do_copy;
+ be_chordal_env_t *chord_env;
+ int do_copy;
+ firm_dbg_module_t *dbg_module;
} lower_env_t;
/* holds a perm register pair */
PERM_COPY
} perm_type_t;
+/* structure to represent cycles or chains in a perm */
typedef struct _perm_cycle_t {
const arch_register_t **elems; /**< the registers in the cycle */
int n_elems; /**< number of elements in the cycle */
return -1;
}
+/* returns the number register pairs marked as checked */
static int get_n_checked_pairs(reg_pair_t *pairs, int n) {
int i, n_checked = 0;
static ir_node *get_node_for_register(reg_pair_t *pairs, int n, const arch_register_t *reg, int in_out) {
int i;
- for (i = 0; i < n; i++) {
- if (in_out) {
+ if (in_out) {
+ for (i = 0; i < n; i++) {
/* out register matches */
if (pairs[i].out_reg->index == reg->index)
return pairs[i].out_node;
}
- else {
+ }
+ else {
+ for (i = 0; i < n; i++) {
/* in register matches */
if (pairs[i].in_reg->index == reg->index)
return pairs[i].in_node;
return NULL;
}
+/**
+ * Gets the index in the register pair array where the in/out register
+ * corresponds to reg_idx.
+ *
+ * @param pairs The array of register pairs
+ * @param n The number of pairs
+ * @param reg The register index to look for
+ * @param in_out 0 == look for IN register, 1 == look for OUT register
+ * @return The corresponding index in pairs or -1 if not found
+ */
+static int get_pairidx_for_regidx(reg_pair_t *pairs, int n, int reg_idx, int in_out) {
+ int i;
+
+ if (in_out) {
+ for (i = 0; i < n; i++) {
+ /* out register matches */
+ if (pairs[i].out_reg->index == reg_idx)
+ return i;
+ }
+ }
+ else {
+ for (i = 0; i < n; i++) {
+ /* in register matches */
+ if (pairs[i].in_reg->index == reg_idx)
+ return i;
+ }
+ }
+
+ return -1;
+}
+
/**
* Gets an array of register pairs and tries to identify a cycle or chain starting
* at position start.
static perm_cycle_t *get_perm_cycle(perm_cycle_t *cycle, reg_pair_t *pairs, int n, int start) {
int head = pairs[start].in_reg->index;
int cur_idx = pairs[start].out_reg->index;
- int n_pairs_done = get_n_checked_pairs(pairs, n) + 1;
+ int cur_pair_idx = start;
+ int n_pairs_done = get_n_checked_pairs(pairs, n);
int idx;
+ perm_type_t cycle_tp = PERM_CYCLE;
+
+ /* We could be right in the middle of a chain, so we need to find the start */
+ while (head != cur_idx) {
+ /* goto previous register in cycle or chain */
+ cur_pair_idx = get_pairidx_for_regidx(pairs, n, head, 1);
+
+ if (cur_pair_idx < 0) {
+ cycle_tp = PERM_CHAIN;
+ break;
+ }
+ else {
+ head = pairs[cur_pair_idx].in_reg->index;
+ start = cur_pair_idx;
+ }
+ }
/* assume worst case: all remaining pairs build a cycle or chain */
- cycle->elems = calloc(n - n_pairs_done, sizeof(cycle->elems[0]));
+ cycle->elems = xcalloc((n - n_pairs_done) * 2, sizeof(cycle->elems[0]));
cycle->n_elems = 2; /* initial number of elements is 2 */
cycle->elems[0] = pairs[start].in_reg;
cycle->elems[1] = pairs[start].out_reg;
- cycle->type = PERM_CHAIN; /* default is CHAIN, only changed when we found a cycle */
-
- /* mark the first pair as checked */
- pairs[start].checked = 1;
+ cycle->type = cycle_tp;
+ cur_idx = pairs[start].out_reg->index;
idx = 2;
/* check for cycle or end of a chain */
- while (cur_idx != head && n_pairs_done < n) {
+ while (cur_idx != head) {
/* goto next register in cycle or chain */
- cur_idx = pairs[cur_idx].out_reg->index;
+ cur_pair_idx = get_pairidx_for_regidx(pairs, n, cur_idx, 0);
+
+ if (cur_pair_idx < 0)
+ break;
+
+ cur_idx = pairs[cur_pair_idx].out_reg->index;
/* it's not the first element: insert it */
if (cur_idx != head) {
- cycle->elems[idx++] = pairs[cur_idx].out_reg;
+ cycle->elems[idx++] = pairs[cur_pair_idx].out_reg;
cycle->n_elems++;
-
- pairs[cur_idx].checked = 1;
- n_pairs_done++;
}
else {
/* we are there where we started -> CYCLE */
}
}
+ /* mark all pairs having one in/out register with cycle in common as checked */
+ for (idx = 0; idx < cycle->n_elems; idx++) {
+ cur_pair_idx = get_pairidx_for_regidx(pairs, n, cycle->elems[idx]->index, 0);
+
+ if (cur_pair_idx >= 0)
+ pairs[cur_pair_idx].checked = 1;
+
+ cur_pair_idx = get_pairidx_for_regidx(pairs, n, cycle->elems[idx]->index, 1);
+
+ if (cur_pair_idx >= 0)
+ pairs[cur_pair_idx].checked = 1;
+ }
+
return cycle;
}
/**
* Lowers a perm node. Resolves cycles and creates a bunch of
* copy and swap operations to permute registers.
+ * Note: The caller of this function has to make sure, that irn
+ * is a Perm node.
*
* @param irn The perm node
+ * @param block The block the perm node belongs to
* @param walk_env The environment
*/
-static void lower_perms_walker(ir_node *irn, void *walk_env) {
- const be_node_factory_t *fact;
+static void lower_perm_node(ir_node *irn, void *walk_env) {
const arch_register_class_t *reg_class;
const arch_env_t *arch_env;
+ firm_dbg_module_t *mod;
lower_env_t *env = walk_env;
reg_pair_t *pairs;
const ir_edge_t *edge;
perm_cycle_t *cycle;
- int n, i, pn, do_copy;
- ir_node *block, *arg, *res, *sched_point, *in[2];
+ int n, i, pn, do_copy, j;
+ ir_node *sched_point, *block, *in[2];
+ ir_node *arg1, *arg2, *res1, *res2;
ir_node *cpyxchg = NULL;
- fact = env->chord_env->main_env->node_factory;
- arch_env = env->chord_env->main_env->arch_env;
+ arch_env = env->chord_env->birg->main_env->arch_env;
do_copy = env->do_copy;
-
- /* check if perm */
- if (! is_Perm(arch_env, irn))
- return;
-
- block = get_nodes_block(irn);
+ mod = env->dbg_module;
+ block = get_nodes_block(irn);
/*
Get the schedule predecessor node to the perm
should be ok.
*/
sched_point = sched_prev(irn);
+ DBG((mod, LEVEL_1, "sched point is %+F\n", sched_point));
assert(sched_point && "Perm is not scheduled or has no predecessor");
n = get_irn_arity(irn);
assert(n == get_irn_n_edges(irn) && "perm's in and out numbers different");
reg_class = arch_get_irn_register(arch_env, get_irn_n(irn, 0))->reg_class;
- pairs = calloc(n, sizeof(pairs[0]));
+ pairs = alloca(n * sizeof(pairs[0]));
/* build the list of register pairs (in, out) */
i = 0;
/* Mark all equal pairs as checked, and exchange the OUT proj with
the IN node. */
- i = 0;
- while (pairs[i].in_reg->index == pairs[i].out_reg->index) {
- /* remove the proj from the schedule */
- sched_remove(pairs[i].out_node);
-
- /* remove the argument from schedule */
- sched_remove(pairs[i].in_node);
+ for (i = 0; i < n; i++) {
+ if (pairs[i].in_reg->index == pairs[i].out_reg->index) {
+ DBG((mod, LEVEL_1, "%+F removing equal perm register pair (%+F, %+F, %s)\n",
+ irn, pairs[i].in_node, pairs[i].out_node, pairs[i].out_reg->name));
+
+ /* We have to check for a special case:
+ The in-node could be a Proj from a Perm. In this case,
+ we need to correct the projnum */
+ if (is_Perm(arch_env, pairs[i].in_node) && is_Proj(pairs[i].in_node)) {
+ set_Proj_proj(pairs[i].out_node, get_Proj_proj(pairs[i].in_node));
+ }
- /* exchange the proj with the argument */
- exchange(pairs[i].out_node, pairs[i].in_node);
+ /* remove the proj from the schedule */
+ sched_remove(pairs[i].out_node);
- /* add the argument after the magic scheduling point */
- sched_add_after(sched_point, pairs[i].in_node);
+ /* reroute the edges from the proj to the argument */
+ edges_reroute(pairs[i].out_node, pairs[i].in_node, env->chord_env->irg);
- pairs[i++].checked = 1;
+ pairs[i].checked = 1;
+ }
}
/* Set do_copy to 0 if it's on but we have no free register */
/* go to the first not-checked pair */
while (pairs[i].checked) i++;
- cycle = calloc(1, sizeof(*cycle));
+ cycle = xcalloc(1, sizeof(*cycle));
cycle = get_perm_cycle(cycle, pairs, n, i);
-//todo: - iff PERM_CYCLE && do_copy -> determine free temp reg and insert copy to/from it before/after
+ DB((mod, LEVEL_1, "%+F: following %s created:\n ", irn, cycle->type == PERM_CHAIN ? "chain" : "cycle"));
+ for (j = 0; j < cycle->n_elems; j++) {
+ DB((mod, LEVEL_1, " %s", cycle->elems[j]->name));
+ }
+ DB((mod, LEVEL_1, "\n"));
+
+ /* We don't need to do anything if we have a Perm with two
+ elements which represents a cycle, because those nodes
+ already represent exchange nodes */
+ if (n == 2 && cycle->type == PERM_CYCLE) {
+ free(cycle);
+ continue;
+ }
+
+//TODO: - iff PERM_CYCLE && do_copy -> determine free temp reg and insert copy to/from it before/after
// the copy cascade (this reduces the cycle into a chain)
/* build copy/swap nodes from back to front */
- for (i = cycle->n_elems - 2; i >= 0; i++) {
- arg = get_node_for_register(pairs, n, cycle->elems[i], 0);
- res = get_node_for_register(pairs, n, cycle->elems[i + 1], 1);
+ for (i = cycle->n_elems - 2; i >= 0; i--) {
+ arg1 = get_node_for_register(pairs, n, cycle->elems[i], 0);
+ arg2 = get_node_for_register(pairs, n, cycle->elems[i + 1], 0);
+
+ res1 = get_node_for_register(pairs, n, cycle->elems[i], 1);
+ res2 = get_node_for_register(pairs, n, cycle->elems[i + 1], 1);
/*
If we have a cycle and don't copy: we need to create exchange nodes
OUT_2 = out node with register i
*/
if (cycle->type == PERM_CYCLE && !do_copy) {
- in[0] = arg;
- in[1] = get_node_for_register(pairs, n, cycle->elems[i + 1], 0);
-
- cpyxchg = new_Perm(fact, reg_class, env->chord_env->irg, block, 2, in);
- set_Proj_pred(res, cpyxchg);
- set_Proj_proj(res, 0);
- set_Proj_pred(get_node_for_register(pairs, n, cycle->elems[i], 1), cpyxchg);
- set_Proj_proj(get_node_for_register(pairs, n, cycle->elems[i], 1), 1);
+ in[0] = arg1;
+ in[1] = arg2;
+
+ /* At this point we have to handle the following problem: */
+ /* */
+ /* If we have a cycle with more than two elements, then */
+ /* this could correspond to the following Perm node: */
+ /* */
+ /* +----+ +----+ +----+ */
+ /* | r1 | | r2 | | r3 | */
+ /* +-+--+ +-+--+ +--+-+ */
+ /* | | | */
+ /* | | | */
+ /* +-+--------+---------+-+ */
+ /* | Perm | */
+ /* +-+--------+---------+-+ */
+ /* | | | */
+ /* | | | */
+ /* +-+--+ +-+--+ +--+-+ */
+ /* |Proj| |Proj| |Proj| */
+ /* | r2 | | r3 | | r1 | */
+ /* +----+ +----+ +----+ */
+ /* */
+ /* This node is about to be split up into two 2x Perm's */
+ /* for which we need 4 Proj's and the one additional Proj */
+ /* of the first Perm has to be one IN of the second. So in */
+ /* general we need to create one additional Proj for each */
+ /* "middle" Perm and set this to one in node of the successor */
+ /* Perm. */
+
+ DBG((mod, LEVEL_1, "%+F creating exchange node (%+F, %s) and (%+F, %s) with\n",
+ irn, arg1, cycle->elems[i]->name, arg2, cycle->elems[i + 1]->name));
+ DBG((mod, LEVEL_1, "%+F (%+F, %s) and (%+F, %s)\n",
+ irn, res1, cycle->elems[i]->name, res2, cycle->elems[i + 1]->name));
+
+ cpyxchg = be_new_Perm(reg_class, env->chord_env->irg, block, 2, in);
+
+ if (i > 0) {
+ /* cycle is not done yet */
+ int pidx = get_pairidx_for_regidx(pairs, n, cycle->elems[i]->index, 0);
+
+ /* create intermediate proj */
+ res1 = new_r_Proj(get_irn_irg(irn), block, cpyxchg, get_irn_mode(res1), 0);
+
+ /* set as in for next Perm */
+ pairs[pidx].in_node = res1;
+ }
+ else {
+ sched_remove(res1);
+ }
+
+ sched_remove(res2);
+
+ set_Proj_pred(res2, cpyxchg);
+ set_Proj_proj(res2, 0);
+ set_Proj_pred(res1, cpyxchg);
+ set_Proj_proj(res1, 1);
+
+ sched_add_after(sched_point, res1);
+ sched_add_after(sched_point, res2);
+
+ arch_set_irn_register(arch_env, res2, cycle->elems[i + 1]);
+ arch_set_irn_register(arch_env, res1, cycle->elems[i]);
+
+ /* insert the copy/exchange node in schedule after the magic schedule node (see above) */
+ sched_add_after(sched_point, cpyxchg);
+
+ DBG((mod, LEVEL_1, "replacing %+F with %+F, placed new node after %+F\n", irn, cpyxchg, sched_point));
+
+ /* set the new scheduling point */
+ sched_point = res1;
}
else {
- cpyxchg = new_Copy(fact, reg_class, env->chord_env->irg, block, arg);
+ DBG((mod, LEVEL_1, "%+F creating copy node (%+F, %s) -> (%+F, %s)\n",
+ irn, arg1, cycle->elems[i]->name, res2, cycle->elems[i + 1]->name));
+
+ cpyxchg = be_new_Copy(reg_class, env->chord_env->irg, block, arg1);
arch_set_irn_register(arch_env, cpyxchg, cycle->elems[i + 1]);
/* remove the proj from the schedule */
- sched_remove(res);
+ sched_remove(res2);
/* exchange copy node and proj */
- exchange(res, cpyxchg);
- }
+ exchange(res2, cpyxchg);
+
+ /* insert the copy/exchange node in schedule after the magic schedule node (see above) */
+ sched_add_after(sched_point, cpyxchg);
- /* insert the copy/exchange node in schedule after the magic schedule node (see above) */
- sched_add_after(sched_point, cpyxchg);
+ /* set the new scheduling point */
+ sched_point = cpyxchg;
+ }
}
- free(cycle->elems);
+ free((void *) cycle->elems);
free(cycle);
}
sched_remove(irn);
}
+
+
+static int get_n_out_edges(const ir_node *irn) {
+ const ir_edge_t *edge;
+ int cnt = 0;
+
+ foreach_out_edge(irn, edge) {
+ cnt++;
+ }
+
+ return cnt;
+}
+
+static ir_node *belower_skip_proj(ir_node *irn) {
+ while(is_Proj(irn))
+ irn = get_Proj_pred(irn);
+ return irn;
+}
+
+static void fix_in(ir_node *irn, ir_node *old, ir_node *nw) {
+ int i, n;
+
+ irn = belower_skip_proj(irn);
+ n = get_irn_arity(irn);
+
+ for (i = 0; i < n; i++) {
+ if (get_irn_n(irn, i) == old) {
+ set_irn_n(irn, i, nw);
+ break;
+ }
+ }
+}
+
+static void gen_assure_different_pattern(ir_node *irn, be_irg_t *birg, ir_node *other_different) {
+ const arch_env_t *arch_env = birg->main_env->arch_env;
+ ir_node *in[2], *keep, *cpy, *temp;
+ ir_node *block = get_nodes_block(irn);
+ firm_dbg_module_t *mod = firm_dbg_register("firm.be.lower");
+ const arch_register_class_t *cls = arch_get_irn_reg_class(arch_env, other_different, -1);
+
+ if (arch_irn_is(arch_env, other_different, ignore) || ! mode_is_datab(get_irn_mode(other_different))) {
+ DBG((mod, LEVEL_1, "ignore constraint for %+F because other_irn is ignore or not a datab node\n", irn));
+ return;
+ }
+
+ /* Make a not spillable copy of the different node */
+ /* this is needed because the different irn could be */
+ /* in block far far away */
+ /* The copy is optimized later if not needed */
+
+ temp = new_rd_Unknown(birg->irg, get_irn_mode(other_different));
+ cpy = be_new_Copy(cls, birg->irg, block, temp);
+ be_node_set_flags(cpy, BE_OUT_POS(0), arch_irn_flags_dont_spill);
+
+ in[0] = irn;
+ in[1] = cpy;
+
+ /* Let the irn use the copy instead of the old other_different */
+ fix_in(irn, other_different, cpy);
+
+ /* Add the Keep resp. CopyKeep and reroute the users */
+ /* of the other_different irn in case of CopyKeep. */
+ if (get_n_out_edges(other_different) == 0) {
+ keep = be_new_Keep(cls, birg->irg, block, 2, in);
+ }
+ else {
+ keep = be_new_CopyKeep_single(cls, birg->irg, block, cpy, irn, get_irn_mode(other_different));
+ be_node_set_reg_class(keep, 1, cls);
+ edges_reroute(other_different, keep, birg->irg);
+ }
+
+ /* after rerouting: let the copy point to the other_different irn */
+ set_irn_n(cpy, 0, other_different);
+
+ DBG((mod, LEVEL_1, "created %+F for %+F to assure should_be_different\n", keep, irn));
+}
+
/**
- * Walks over all nodes in an irg and performs perm lowering.
+ * Checks if node has a should_be_different constraint in output
+ * and adds a Keep then to assure the constraint.
+ */
+static void assure_different_constraints(ir_node *irn, be_irg_t *birg) {
+ const arch_env_t *arch_env = birg->main_env->arch_env;
+ const arch_register_req_t *req;
+ arch_register_req_t req_temp;
+ int i, n;
+
+ req = arch_get_register_req(arch_env, &req_temp, irn, -1);
+
+ if (req) {
+ if (arch_register_req_is(req, should_be_different)) {
+ gen_assure_different_pattern(irn, birg, req->other_different);
+ }
+ else if (arch_register_req_is(req, should_be_different_from_all)) {
+ n = get_irn_arity(belower_skip_proj(irn));
+ for (i = 0; i < n; i++) {
+ gen_assure_different_pattern(irn, birg, get_irn_n(belower_skip_proj(irn), i));
+ }
+ }
+ }
+}
+
+
+
+/**
+ * Calls the functions to assure register constraints.
+ *
+ * @param irn The node to be checked for lowering
+ * @param walk_env The walker environment
+ */
+static void assure_constraints_walker(ir_node *irn, void *walk_env) {
+ if (is_Block(irn))
+ return;
+
+ if (mode_is_datab(get_irn_mode(irn)))
+ assure_different_constraints(irn, walk_env);
+
+ return;
+}
+
+
+
+/**
+ * Walks over all nodes to assure register constraints.
+ *
+ * @param birg The birg structure containing the irg
+ */
+void assure_constraints(be_irg_t *birg) {
+ irg_walk_blkwise_graph(birg->irg, NULL, assure_constraints_walker, birg);
+}
+
+
+
+/**
+ * Calls the corresponding lowering function for the node.
+ *
+ * @param irn The node to be checked for lowering
+ * @param walk_env The walker environment
+ */
+static void lower_nodes_after_ra_walker(ir_node *irn, void *walk_env) {
+ lower_env_t *env = walk_env;
+ const arch_env_t *arch_env = env->chord_env->birg->main_env->arch_env;
+
+ if (!is_Block(irn) && !is_Proj(irn)) {
+ if (is_Perm(arch_env, irn)) {
+ lower_perm_node(irn, walk_env);
+ }
+ }
+
+ return;
+}
+
+
+
+/**
+ * Walks over all blocks in an irg and performs lowering need to be
+ * done after register allocation (e.g. perm lowering).
*
* @param chord_env The chordal environment containing the irg
* @param do_copy 1 == resolve cycles with a free reg if available
*/
-void lower_perms(be_chordal_env_t *chord_env, int do_copy) {
+void lower_nodes_after_ra(be_chordal_env_t *chord_env, int do_copy) {
lower_env_t env;
- env.chord_env = chord_env;
- env.do_copy = do_copy;
+ env.chord_env = chord_env;
+ env.do_copy = do_copy;
+ env.dbg_module = firm_dbg_register("firm.be.lower");
- irg_block_walk_graph(chord_env->irg, NULL, lower_perms_walker, &env);
+ irg_walk_blkwise_graph(chord_env->irg, NULL, lower_nodes_after_ra_walker, &env);
}
+
+#undef is_Perm
+#undef is_Call
projects / libfirm / blobdiff