2 * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20 /* Mips implementation of list scheduler selector */
30 #include "mips_scheduler.h"
32 #include "../besched_t.h"
37 #include "gen_mips_regalloc_if.h"
39 #include "mips_new_nodes.h"
41 list_sched_selector_t mips_sched_selector;
44 const arch_env_t* arch_env;
47 * This array holds an entry for each register that specifies how much cycles
48 * have to pass before we can access that register again
49 * (because mips will write the register value back in the WB phase of the pipeline)
51 int busy_registers[N_mips_gp_REGS];
57 /* Matze: deprecated and totally broken */
60 static void *mips_scheduler_init_graph(const list_sched_selector_t *vtab, const arch_env_t *arch_env, ir_graph *irg)
62 mips_sched_env_t *sched_env = xmalloc(sizeof(sched_env[0]));
63 memset(sched_env, 0, sizeof(sched_env[0]));
65 sched_env->arch_env = arch_env;
66 sched_env->div_set = new_pset(pset_default_ptr_cmp, 4);
71 static void mips_scheduler_finish_graph(void* graph_env)
73 mips_sched_env_t *sched_env = (mips_sched_env_t*) graph_env;
74 del_pset(sched_env->div_set);
77 static void *mips_scheduler_init_block(void *graph_env, ir_node *block)
79 mips_sched_env_t *sched_env = (mips_sched_env_t*) graph_env;
80 assert(pset_count(sched_env->div_set) == 0);
82 // TODO later we might have blocks that don't end in a jump
83 memset(&sched_env->busy_registers, 0, sizeof(sched_env->busy_registers));
84 sched_env->block = block;
85 sched_env->last_nop = NULL;
89 static void mips_scheduler_finish_block(void* graph_env)
91 mips_sched_env_t *sched_env = (mips_sched_env_t*) graph_env;
92 // attach last nop to end node (so that firm doesn't discard it)
93 if(sched_env->last_nop != NULL) {
94 ir_node* end = get_irg_end(get_irn_irg(sched_env->block));
98 sched_env->block = NULL;
101 static int mips_scheduler_to_appear_in_schedule(void *block_env, const ir_node *irn)
103 return is_mips_irn(irn) && !is_mips_zero(irn) && !is_mips_reinterpret_conv(irn) && !is_mips_fallthrough(irn);
106 static void mips_collect_mflohis(pset* set, ir_node* node) {
107 // construct a list of nodes that need to be scheduled before
108 // we are allowed to schedule another div or mul instruction
109 const ir_edge_t *edge, *edge2;
111 if(is_mips_div(node)) {
112 foreach_out_edge(node, edge) {
113 const ir_node* node2 = get_edge_src_irn(edge);
115 assert(is_Proj(node2));
116 foreach_out_edge(node2, edge2) {
117 const ir_node* node3 = get_edge_src_irn(edge2);
118 if(is_mips_mfhi(node3) || is_mips_mflo(node3))
119 pset_insert_ptr(set, node3);
122 } else if(is_mips_mult(node)) {
123 foreach_out_edge(node, edge) {
124 const ir_node* node2 = get_edge_src_irn(edge);
126 if(is_mips_mfhi(node2) || is_mips_mflo(node2))
127 pset_insert_ptr(set, node2);
132 static int mips_scheduler_node_allowed(mips_sched_env_t *sched_env, ir_node* node)
134 if(pset_count(sched_env->div_set) != 0 && (is_mips_div(node) || is_mips_mult(node))) {
141 static ir_node *mips_scheduler_select(void *block_env, nodeset *ready_set, nodeset *live_set)
143 mips_sched_env_t *sched_env = (mips_sched_env_t*) block_env;
144 const arch_env_t *arch_env = (const arch_env_t*) sched_env->arch_env;
145 ir_node *node = NULL;
146 ir_node *block = sched_env->block;
147 ir_node *condjmp = NULL;
148 ir_graph *irg = get_irn_irg(block);
149 int have_non_branch_nodes = 0;
151 // test all nodes in the ready set and take the first non-branch that
153 for (node = nodeset_first(ready_set); node != NULL; node = nodeset_next(ready_set)) {
154 if (arch_irn_class_is(arch_env, node, branch)) {
155 if (is_irn_forking(node))
160 have_non_branch_nodes = 1;
162 if (mips_scheduler_node_allowed(sched_env, node))
164 nodeset_break(ready_set);
166 // TODO update busy_registers
168 if (is_mips_div(node) || is_mips_mult(node)) {
169 mips_collect_mflohis(sched_env->div_set, node);
170 } else if(is_mips_mflo(node) || is_mips_mfhi(node)) {
171 pset_remove_ptr(sched_env->div_set, node);
178 // if we arrive here no non-branch node was found that we can emit
180 // return a branch if there are just branches left
181 if(!have_non_branch_nodes) {
182 // schedule conditional branches before non-conditional ones
183 if(condjmp != NULL) {
186 node = nodeset_first(ready_set);
187 assert(arch_irn_class_is(arch_env, node, branch));
188 nodeset_break(ready_set);
193 node = new_rd_mips_nop(NULL, irg, block, mode_M);
201 * Returns the reg_pressure scheduler with to_appear_in_schedule() overloaded
203 const list_sched_selector_t *mips_get_list_sched_selector(const void *self, list_sched_selector_t *selector)
206 memset(&mips_sched_selector, 0, sizeof(mips_sched_selector));
207 mips_sched_selector.init_graph = mips_scheduler_init_graph;
208 mips_sched_selector.init_block = mips_scheduler_init_block;
209 mips_sched_selector.select = mips_scheduler_select;
210 mips_sched_selector.to_appear_in_schedule = mips_scheduler_to_appear_in_schedule;
211 mips_sched_selector.finish_block = mips_scheduler_finish_block;
212 mips_sched_selector.finish_graph = mips_scheduler_finish_graph;
213 //return &mips_sched_selector;
218 const ilp_sched_selector_t *mips_get_ilp_sched_selector(const void *self) {