X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbelower.c;h=87bdea31670141bb1586098dd558a5ec5e348c81;hb=f804d333c7b5459c3c1a6bfc188ecdc54346be73;hp=b11244c36b794461b9ee16e9563c9df00077e3c6;hpb=f16804fdb481bc389a79d4aa7257b3b7a7e02e0b;p=libfirm diff --git a/ir/be/belower.c b/ir/be/belower.c index b11244c36..87bdea316 100644 --- a/ir/be/belower.c +++ b/ir/be/belower.c @@ -11,23 +11,38 @@ #include "config.h" #endif +#include + +#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 _WIN32 +#include +#else +#include +#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 */ @@ -48,6 +63,7 @@ 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 +81,7 @@ 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 +107,15 @@ 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 +125,37 @@ 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. @@ -118,32 +168,49 @@ 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 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 */ @@ -151,37 +218,49 @@ static perm_cycle_t *get_perm_cycle(perm_cycle_t *cycle, reg_pair_t *pairs, int } } + /* 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; 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 @@ -190,13 +269,14 @@ 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); 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; @@ -217,21 +297,26 @@ 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 */ @@ -245,16 +330,33 @@ static void lower_perms_walker(ir_node *irn, void *walk_env) { /* 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); + /* build copy/swap nodes */ + for (i = 0; i < cycle->n_elems - 1; 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 @@ -265,28 +367,48 @@ 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); - - 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; + + 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); + + 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 = 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); + + DBG((mod, LEVEL_1, "replacing %+F with %+F, placed new node after %+F\n", irn, cpyxchg, sched_point)); } free(cycle->elems); @@ -297,17 +419,214 @@ static void lower_perms_walker(ir_node *irn, void *walk_env) { sched_remove(irn); } + + +/** + * 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; +} + + + /** - * Walks over all nodes in an irg and performs perm lowering. + * Calls the backend code generator functions to lower Spill and + * Reload nodes into Store and Load. The backend is fully responsible + * for creating the new nodes and setting their input correct. + * Note: The caller of this has to make sure that irn is a Spill + * or Reload! + * + * @param irn The Spill/Reload node + * @param walk_env The walker environment + */ +static void lower_spill_reload(ir_node *irn, void *walk_env) { + lower_env_t *env = walk_env; + arch_code_generator_t *cg = env->chord_env->main_env->cg; + const arch_env_t *aenv = env->chord_env->main_env->arch_env; + ir_node *res = NULL; + ir_node *sched_point; + + if (be_is_Spill(irn) && cg->impl->lower_spill) { + res = cg->impl->lower_spill(cg, irn); + } + else if (be_is_Reload(irn) && cg->impl->lower_reload) { + res = cg->impl->lower_reload(cg, irn); + if (res && res != irn) { + /* copy the result register from the reload to the load */ + arch_set_irn_register(aenv, res, arch_get_irn_register(aenv, irn)); + } + } + + if (res && res != irn) { + sched_point = sched_prev(irn); + sched_remove(irn); + exchange(irn, res); + sched_add_after(sched_point, res); + } + else { + DBG((env->dbg_module, LEVEL_1, "node %+F not lowered\n", irn)); + } + + return; +} + + +/** + * 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. + * + * @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->main_env->arch_env; + + if (!is_Block(irn) && !is_Proj(irn)) { + if (is_Perm(arch_env, irn)) { + lower_perm_node(irn, walk_env); + } + else if (be_is_Spill(irn) || be_is_Reload(irn)) { + lower_spill_reload(irn, walk_env); + } + } + + return; +} + + + +/** + * 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_perms(be_chordal_env_t *chord_env, int do_copy) { +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). + * + * @param chord_env The chordal environment containing the irg + * @param do_copy 1 == resolve cycles with a free reg if available + */ +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