X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbepeephole.c;h=85c242c98b635be14f65fad293397ac2f5516c04;hb=df2faee01a5832057bb3ca0ba5f67e979c916e19;hp=fedab047bc58f5f215d4bcd7108ffeed2c6b17a8;hpb=ea6e9be0bea5ad0079ab09d5e494cf7b5c889552;p=libfirm diff --git a/ir/be/bepeephole.c b/ir/be/bepeephole.c index fedab047b..85c242c98 100644 --- a/ir/be/bepeephole.c +++ b/ir/be/bepeephole.c @@ -21,7 +21,6 @@ * @file * @brief Peephole optimisation framework keeps track of which registers contain which values * @author Matthias Braun - * @version $Id$ */ #include "config.h" @@ -33,11 +32,13 @@ #include "irprintf.h" #include "ircons.h" #include "irgmod.h" +#include "heights.h" #include "error.h" #include "beirg.h" #include "belive_t.h" #include "bearch.h" +#include "beintlive_t.h" #include "benode.h" #include "besched.h" #include "bemodule.h" @@ -47,39 +48,32 @@ DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;) static const arch_env_t *arch_env; static be_lv_t *lv; static ir_node *current_node; -ir_node ***register_values; +ir_node **register_values; static void clear_reg_value(ir_node *node) { - const arch_register_t *reg; - const arch_register_class_t *cls; - unsigned reg_idx; - unsigned cls_idx; + const arch_register_t *reg; + unsigned reg_idx; if (!mode_is_data(get_irn_mode(node))) return; - reg = arch_get_irn_register(node); + reg = arch_get_irn_register(node); if (reg == NULL) { panic("No register assigned at %+F", node); } if (reg->type & arch_register_type_virtual) return; - cls = arch_register_get_class(reg); - reg_idx = arch_register_get_index(reg); - cls_idx = arch_register_class_index(cls); + reg_idx = reg->global_index; - //assert(register_values[cls_idx][reg_idx] != NULL); DB((dbg, LEVEL_1, "Clear Register %s\n", reg->name)); - register_values[cls_idx][reg_idx] = NULL; + register_values[reg_idx] = NULL; } static void set_reg_value(ir_node *node) { - const arch_register_t *reg; - const arch_register_class_t *cls; - unsigned reg_idx; - unsigned cls_idx; + const arch_register_t *reg; + unsigned reg_idx; if (!mode_is_data(get_irn_mode(node))) return; @@ -90,26 +84,18 @@ static void set_reg_value(ir_node *node) } if (reg->type & arch_register_type_virtual) return; - cls = arch_register_get_class(reg); - reg_idx = arch_register_get_index(reg); - cls_idx = arch_register_class_index(cls); + reg_idx = reg->global_index; DB((dbg, LEVEL_1, "Set Register %s: %+F\n", reg->name, node)); - register_values[cls_idx][reg_idx] = node; + register_values[reg_idx] = node; } static void clear_defs(ir_node *node) { /* clear values defined */ - if (get_irn_mode(node) == mode_T) { - const ir_edge_t *edge; - foreach_out_edge(node, edge) { - ir_node *proj = get_edge_src_irn(edge); - clear_reg_value(proj); - } - } else { - clear_reg_value(node); - } + be_foreach_value(node, value, + clear_reg_value(value); + ); } static void set_uses(ir_node *node) @@ -132,26 +118,34 @@ void be_peephole_new_node(ir_node * nw) /** * must be called from peephole optimisations before a node will be killed * and its users will be redirected to new_node. - * so bepeephole can update it's internal state. + * so bepeephole can update its internal state. * - * Note: killing a node and rewiring os only allowed if new_node produces + * Note: killing a node and rewiring is only allowed if new_node produces * the same registers as old_node. */ static void be_peephole_before_exchange(const ir_node *old_node, ir_node *new_node) { - const arch_register_t *reg; - const arch_register_class_t *cls; - unsigned reg_idx; - unsigned cls_idx; + const arch_register_t *reg; + unsigned reg_idx; + bool old_is_current = false; DB((dbg, LEVEL_1, "About to exchange and kill %+F with %+F\n", old_node, new_node)); + assert(sched_is_scheduled(skip_Proj_const(old_node))); + assert(sched_is_scheduled(skip_Proj(new_node))); + if (current_node == old_node) { + old_is_current = true; + /* next node to be processed will be killed. Its scheduling predecessor * must be processed next. */ current_node = sched_next(current_node); assert (!is_Bad(current_node)); + + /* we can't handle liveness updates correctly when exchange current node + * with something behind it */ + assert(value_dominates(skip_Proj(new_node), skip_Proj_const(old_node))); } if (!mode_is_data(get_irn_mode(old_node))) @@ -164,12 +158,9 @@ static void be_peephole_before_exchange(const ir_node *old_node, assert(reg == arch_get_irn_register(new_node) && "KILLING a node and replacing by different register is not allowed"); - cls = arch_register_get_class(reg); - reg_idx = arch_register_get_index(reg); - cls_idx = arch_register_class_index(cls); - - if (register_values[cls_idx][reg_idx] == old_node) { - register_values[cls_idx][reg_idx] = new_node; + reg_idx = reg->global_index; + if (register_values[reg_idx] == old_node || old_is_current) { + register_values[reg_idx] = new_node; } be_liveness_remove(lv, old_node); @@ -188,23 +179,14 @@ void be_peephole_exchange(ir_node *old, ir_node *nw) */ static void process_block(ir_node *block, void *data) { - unsigned n_classes; - unsigned i; - int l; (void) data; /* construct initial register assignment */ - n_classes = arch_env->n_register_classes; - for (i = 0; i < n_classes; ++i) { - const arch_register_class_t *cls = &arch_env->register_classes[i]; - unsigned n_regs = arch_register_class_n_regs(cls); - memset(register_values[i], 0, sizeof(ir_node*) * n_regs); - } + memset(register_values, 0, sizeof(ir_node*) * arch_env->n_registers); - assert(lv->nodes && "live sets must be computed"); + assert(lv->sets_valid && "live sets must be computed"); DB((dbg, LEVEL_1, "\nProcessing block %+F (from end)\n", block)); - be_lv_foreach(lv, block, be_lv_state_end, l) { - ir_node *node = be_lv_get_irn(lv, block, l); + be_lv_foreach(lv, block, be_lv_state_end, node) { set_reg_value(node); } DB((dbg, LEVEL_1, "\nstart processing\n")); @@ -237,24 +219,167 @@ static void process_block(ir_node *block, void *data) /** * Check whether the node has only one user. Explicitly ignore the anchor. */ -static int has_only_one_user(ir_node *node) +bool be_has_only_one_user(ir_node *node) { - int n = get_irn_n_edges(node); - const ir_edge_t *edge; + int n = get_irn_n_edges(node); + int n_users; if (n <= 1) return 1; - if (n > 2) - return 0; - + n_users = 0; foreach_out_edge(node, edge) { ir_node *src = get_edge_src_irn(edge); - if (is_Anchor(src)) - return 1; + /* ignore anchor and keep-alive edges */ + if (is_Anchor(src) || is_End(src)) + continue; + n_users++; } - return 0; + return n_users == 1; +} + +static inline bool overlapping_regs(const arch_register_t *reg0, + const arch_register_req_t *req0, const arch_register_t *reg1, + const arch_register_req_t *req1) +{ + if (reg0 == NULL || reg1 == NULL) + return false; + return reg0->global_index < (unsigned)reg1->global_index + req1->width + && reg1->global_index < (unsigned)reg0->global_index + req0->width; +} + +bool be_can_move_down(ir_heights_t *heights, const ir_node *node, + const ir_node *before) +{ + assert(get_nodes_block(node) == get_nodes_block(before)); + assert(sched_get_time_step(node) < sched_get_time_step(before)); + + int node_arity = get_irn_arity(node); + ir_node *schedpoint = sched_next(node); + + while (schedpoint != before) { + /* schedpoint must not use our computed values */ + if (heights_reachable_in_block(heights, schedpoint, node)) + return false; + + /* schedpoint must not overwrite registers of our inputs */ + for (int i = 0; i < node_arity; ++i) { + ir_node *in = get_irn_n(node, i); + const arch_register_t *reg = arch_get_irn_register(in); + if (reg == NULL) + continue; + const arch_register_req_t *in_req + = arch_get_irn_register_req_in(node, i); + be_foreach_out(schedpoint, o) { + const arch_register_t *outreg + = arch_get_irn_register_out(schedpoint, o); + const arch_register_req_t *outreq + = arch_get_irn_register_req_out(schedpoint, o); + if (overlapping_regs(reg, in_req, outreg, outreq)) + return false; + } + } + + schedpoint = sched_next(schedpoint); + } + return true; +} + +bool be_can_move_up(ir_heights_t *heights, const ir_node *node, + const ir_node *after) +{ + const ir_node *node_block = get_nodes_block(node); + const ir_node *after_block = get_block_const(after); + const ir_node *schedpoint; + if (node_block != after_block) { + /* currently we can move up exactly 1 block */ + assert(get_Block_cfgpred_block(node_block, 0) == after_block); + ir_node *first = sched_first(node_block); + + /* do not move nodes changing memory */ + if (is_memop(node)) { + ir_node *meminput = get_memop_mem(node); + if (!is_NoMem(meminput)) + return false; + } + + /* make sure we can move to the beginning of the succ block */ + if (node != first && !be_can_move_up(heights, node, sched_prev(first))) + return false; + + /* check if node overrides any of live-in values of other successors */ + ir_graph *irg = get_irn_irg(node); + be_lv_t *lv = be_get_irg_liveness(irg); + foreach_block_succ(after_block, edge) { + ir_node *succ = get_edge_src_irn(edge); + if (succ == node_block) + continue; + + be_lv_foreach(lv, succ, be_lv_state_in, live_node) { + const arch_register_t *reg = arch_get_irn_register(live_node); + const arch_register_req_t *req = arch_get_irn_register_req(live_node); + be_foreach_out(node, o) { + const arch_register_t *outreg + = arch_get_irn_register_out(node, o); + const arch_register_req_t *outreq + = arch_get_irn_register_req_out(node, o); + if (overlapping_regs(outreg, outreq, reg, req)) + return false; + } + } + sched_foreach(succ, phi) { + if (!is_Phi(phi)) + break; + const arch_register_t *reg = arch_get_irn_register(phi); + const arch_register_req_t *req = arch_get_irn_register_req(phi); + be_foreach_out(node, o) { + const arch_register_t *outreg + = arch_get_irn_register_out(node, o); + const arch_register_req_t *outreq + = arch_get_irn_register_req_out(node, o); + if (overlapping_regs(outreg, outreq, reg, req)) + return false; + } + } + } + schedpoint = sched_last(after_block); + } else { + schedpoint = sched_prev(node); + } + + /* move schedule upwards until we hit the "after" node */ + while (schedpoint != after) { + /* TODO: the following heights query only works for nodes in the same + * block, otherwise we have to be conservative here */ + if (get_nodes_block(node) != get_nodes_block(schedpoint)) + return false; + /* node must not depend on schedpoint */ + if (heights_reachable_in_block(heights, node, schedpoint)) + return false; + + /* node must not overwrite registers used by schedpoint */ + int arity = get_irn_arity(schedpoint); + for (int i = 0; i < arity; ++i) { + const arch_register_t *reg + = arch_get_irn_register_in(schedpoint, i); + if (reg == NULL) + continue; + const arch_register_req_t *in_req + = arch_get_irn_register_req_in(schedpoint, i); + be_foreach_out(node, o) { + const arch_register_t *outreg + = arch_get_irn_register_out(node, o); + const arch_register_req_t *outreq + = arch_get_irn_register_req_out(node, o); + if (overlapping_regs(outreg, outreq, reg, in_req)) + return false; + } + } + + schedpoint = sched_prev(schedpoint); + } + return true; } /* @@ -271,28 +396,12 @@ ir_node *be_peephole_IncSP_IncSP(ir_node *node) if (!be_is_IncSP(pred)) return node; - if (!has_only_one_user(pred)) + if (!be_has_only_one_user(pred)) return node; pred_offs = be_get_IncSP_offset(pred); curr_offs = be_get_IncSP_offset(node); - - if (pred_offs == BE_STACK_FRAME_SIZE_EXPAND) { - if (curr_offs != BE_STACK_FRAME_SIZE_SHRINK) { - return node; - } - offs = 0; - } else if (pred_offs == BE_STACK_FRAME_SIZE_SHRINK) { - if (curr_offs != BE_STACK_FRAME_SIZE_EXPAND) { - return node; - } - offs = 0; - } else if (curr_offs == BE_STACK_FRAME_SIZE_EXPAND || - curr_offs == BE_STACK_FRAME_SIZE_SHRINK) { - return node; - } else { - offs = curr_offs + pred_offs; - } + offs = curr_offs + pred_offs; /* add node offset to pred and remove our IncSP */ be_set_IncSP_offset(pred, offs); @@ -303,34 +412,24 @@ ir_node *be_peephole_IncSP_IncSP(ir_node *node) void be_peephole_opt(ir_graph *irg) { - unsigned n_classes; - unsigned i; - +#if 0 /* we sometimes find BadE nodes in float apps like optest_float.c or * kahansum.c for example... */ - be_liveness_invalidate(be_get_irg_liveness(irg)); - be_liveness_assure_sets(be_assure_liveness(irg)); + be_invalidate_live_sets(irg); +#endif + be_assure_live_sets(irg); arch_env = be_get_irg_arch_env(irg); lv = be_get_irg_liveness(irg); - n_classes = arch_env->n_register_classes; - register_values = XMALLOCN(ir_node**, n_classes); - for (i = 0; i < n_classes; ++i) { - const arch_register_class_t *cls = &arch_env->register_classes[i]; - unsigned n_regs = arch_register_class_n_regs(cls); - register_values[i] = XMALLOCN(ir_node*, n_regs); - } + register_values = XMALLOCN(ir_node*, arch_env->n_registers); irg_block_walk_graph(irg, process_block, NULL, NULL); - for (i = 0; i < n_classes; ++i) { - xfree(register_values[i]); - } xfree(register_values); } -BE_REGISTER_MODULE_CONSTRUCTOR(be_init_peephole); +BE_REGISTER_MODULE_CONSTRUCTOR(be_init_peephole) void be_init_peephole(void) { FIRM_DBG_REGISTER(dbg, "firm.be.peephole");