//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 */
- for (i = 0; i < cycle->n_elems - 1; i++) {
+ /* build copy/swap nodes from back to front */
+ 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);
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",
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 */
+ res2 = new_r_Proj(get_irn_irg(irn), block, cpyxchg, get_irn_mode(res1), 0);
+
+ /* set as in for next Perm */
+ pairs[pidx].in_node = res2;
+ }
+ else {
+ sched_remove(res2);
+ }
+
sched_remove(res1);
- sched_remove(res2);
set_Proj_pred(res2, cpyxchg);
set_Proj_proj(res2, 0);
/* 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;
DBG((mod, LEVEL_1, "replacing %+F with %+F, placed new node after %+F\n", irn, cpyxchg, sched_point));
}
- free(cycle->elems);
+ free((void *) cycle->elems);
free(cycle);
}
-/**
- * Adds Projs to keep nodes for each register class, which eats the
- * caller saved registers.
- * Note: The caller has to make sure, that call is a Call
- *
- * @param call The Call node
- * @param walk_env The walker environment
- */
-static void lower_call_node(ir_node *call, const void *walk_env) {
- const arch_env_t *arch_env = walk_env;
- int bitset_idx = 0;
- int set_size = 0;
- arch_isa_t *isa = arch_env_get_isa(arch_env);
- const ir_node *proj_T = NULL;
- ir_node *block = get_nodes_block(call);
- const arch_register_class_t *reg_class;
- int i, j, pn, keep_arity;
- ir_node **in_keep;
- bitset_t *proj_set;
- const ir_edge_t *edge;
- const arch_register_t *reg;
-
- /* Prepare the bitset where we store the projnums which are already in use*/
- for (i = 0; i < arch_isa_get_n_reg_class(isa); i++) {
- reg_class = arch_isa_get_reg_class(isa, i);
- set_size += arch_register_class_n_regs(reg_class);
- }
-
- in_keep = xmalloc(set_size * sizeof(ir_node *));
-
- proj_set = bitset_malloc(set_size);
- bitset_clear_all(proj_set);
-
- /* check if there is a ProjT node and which arguments are used */
- foreach_out_edge(call, edge) {
- if (get_irn_mode(get_edge_src_irn(edge)) == mode_T)
- proj_T = get_edge_src_irn(edge);
- }
-
- /* set all used arguments */
- if (proj_T) {
- foreach_out_edge(proj_T, edge) {
- ir_node *proj = get_edge_src_irn(edge);
-
- assert(is_Proj(proj));
- pn = isa->impl->handle_call_proj(isa, proj, 0);
- bitset_set(proj_set, pn);
- }
- }
- else {
- proj_T = new_r_Proj(current_ir_graph, block, call, mode_T, pn_Call_T_result);
- }
-
- /* Create for each caller save register a proj (keep node argument) */
- /* if this proj is not already present */
- for (i = 0; i < arch_isa_get_n_reg_class(isa); i++) {
-
- /* reset the keep input, as we need one keep for each register class */
- memset(in_keep, 0, set_size * sizeof(ir_node *));
- keep_arity = 0;
- reg_class = arch_isa_get_reg_class(isa, i);
-
- for (j = 0; j < arch_register_class_n_regs(reg_class); j++) {
- reg = arch_register_for_index(reg_class, j);
-
- /* only check caller save registers */
- if (arch_register_type_is(reg, caller_saved)) {
-
- /* Only create new proj, iff not already present */
- if (!bitset_is_set(proj_set, bitset_idx)) {
- ir_node *proj = new_r_Proj(current_ir_graph, block, (ir_node *)proj_T, mode_Is, bitset_idx);
-
- pn = isa->impl->handle_call_proj(isa, proj, 1);
- in_keep[keep_arity++] = proj;
- }
-
- bitset_idx++;
- }
- }
-
- /* ok, we found some caller save register which are not in use but must be saved */
- if (keep_arity) {
- be_new_Keep(reg_class, current_ir_graph, block, keep_arity, in_keep);
- }
- }
-
- bitset_free(proj_set);
- return;
-}
-
-
-
/**
* Calls the backend code generator functions to lower Spill and
* Reload nodes into Store and Load. The backend is fully responsible
}
-/**
- * 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_before_sched_walker(ir_node *irn, const void *walk_env) {
- const arch_env_t *arch_env = walk_env;
-
- if (!is_Block(irn) && !is_Proj(irn)) {
- if (is_Call(arch_env, irn)) {
- lower_call_node(irn, walk_env);
- }
- }
-
- return;
-}
-
/**
* Calls the corresponding lowering function for the node.
-/**
- * Walks over all blocks in an irg and performs lowering need
- * to be done before scheduling (e.g. call lowering).
- *
- * @param chord_env The chordal environment containing the irg
- * @param do_copy 1 == resolve cycles with a free reg if available
- */
-void lower_nodes_before_sched(ir_graph *irg, const void *env) {
- irg_walk_blkwise_graph(irg, NULL, lower_nodes_before_sched_walker, (void *)env);
-}
-
-
-
/**
* Walks over all blocks in an irg and performs lowering need to be
* done after register allocation (e.g. perm and spill/reload lowering).
projects / libfirm / blobdiff