X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbelower.c;h=23415d164e75ce741df224d12a1e0a6cf4d677bc;hb=b46c894cf05a8c569d404ba0ef92c384d76e34d6;hp=b11244c36b794461b9ee16e9563c9df00077e3c6;hpb=f16804fdb481bc389a79d4aa7257b3b7a7e02e0b;p=libfirm diff --git a/ir/be/belower.c b/ir/be/belower.c index b11244c36..23415d164 100644 --- a/ir/be/belower.c +++ b/ir/be/belower.c @@ -18,7 +18,7 @@ #include "besched.h" #include "irgmod.h" -#include "iredges.h" +#include "iredges_t.h" #include "irgwalk.h" #undef is_Perm @@ -26,8 +26,9 @@ /* 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 */ @@ -48,6 +49,7 @@ typedef enum _perm_type_t { 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 */ @@ -65,6 +67,7 @@ static int compare_reg_pair(const void *a, const void *b) { 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; @@ -90,13 +93,15 @@ static int get_n_checked_pairs(reg_pair_t *pairs, int n) { 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; @@ -106,6 +111,37 @@ static ir_node *get_node_for_register(reg_pair_t *pairs, int n, const arch_regis 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. @@ -118,6 +154,7 @@ static ir_node *get_node_for_register(reg_pair_t *pairs, int n, const arch_regis 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 cur_pair_idx = start; int n_pairs_done = get_n_checked_pairs(pairs, n) + 1; int idx; @@ -135,20 +172,27 @@ static perm_cycle_t *get_perm_cycle(perm_cycle_t *cycle, reg_pair_t *pairs, int /* check for cycle or end of a chain */ while (cur_idx != head && n_pairs_done < n) { /* 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 */ cycle->type = PERM_CYCLE; } + + /* mark the pair as checked */ + pairs[cur_pair_idx].checked = 1; } return cycle; @@ -159,30 +203,38 @@ static perm_cycle_t *get_perm_cycle(perm_cycle_t *cycle, reg_pair_t *pairs, int * copy and swap operations to permute registers. * * @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) { +static void lower_perm_node(ir_node *irn, void *walk_env) { const be_node_factory_t *fact; 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]; + ir_node *sched_point, *block, *in[2]; + ir_node *arg1, *arg2, *res1, *res2; ir_node *cpyxchg = NULL; + if (is_Block(irn)) + return; + fact = env->chord_env->main_env->node_factory; arch_env = env->chord_env->main_env->arch_env; do_copy = env->do_copy; + mod = env->dbg_module; + block = get_nodes_block(irn); - /* check if perm */ - if (! is_Perm(arch_env, irn)) + /* check if perm + Note: A Proj on a Perm will cause is_Perm() + also to return true */ + if (is_Proj(irn) || ! is_Perm(arch_env, irn)) return; - block = get_nodes_block(irn); - /* Get the schedule predecessor node to the perm NOTE: This works with auto-magic. If we insert the @@ -190,6 +242,7 @@ static void lower_perms_walker(ir_node *irn, void *walk_env) { 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); @@ -217,21 +270,26 @@ static void lower_perms_walker(ir_node *irn, void *walk_env) { /* 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 */ @@ -248,13 +306,24 @@ static void lower_perms_walker(ir_node *irn, void *walk_env) { cycle = calloc(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 + /* 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 @@ -265,31 +334,51 @@ static void lower_perms_walker(ir_node *irn, void *walk_env) { 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); + in[0] = arg1; + in[1] = arg2; + + 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 = 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); + + 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]); } 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 = new_Copy(fact, 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); + + DBG((mod, LEVEL_1, "replacing %+F with %+F, placed new node after %+F\n", irn, cpyxchg, sched_point)); } - free(cycle->elems); +// free(cycle->elems); free(cycle); } @@ -298,7 +387,7 @@ static void lower_perms_walker(ir_node *irn, void *walk_env) { } /** - * Walks over all nodes in an irg and performs perm lowering. + * Walks over all blocks in an irg and performs perm lowering. * * @param chord_env The chordal environment containing the irg * @param do_copy 1 == resolve cycles with a free reg if available @@ -306,8 +395,9 @@ static void lower_perms_walker(ir_node *irn, void *walk_env) { void lower_perms(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("ir.be.lower"); - irg_block_walk_graph(chord_env->irg, NULL, lower_perms_walker, &env); + irg_walk_blkwise_graph(chord_env->irg, NULL, lower_perm_node, &env); }