1 /* Mips implementation of list scheduler selector */
11 #include "mips_scheduler.h"
13 #include "../besched_t.h"
18 #include "gen_mips_regalloc_if.h"
20 #include "mips_new_nodes.h"
22 list_sched_selector_t mips_sched_selector;
25 const arch_env_t* arch_env;
28 * This array holds an entry for each register that specifies how much cycles
29 * have to pass before we can access that register again
30 * (because mips will write the register value back in the WB phase of the pipeline)
32 int busy_registers[N_mips_gp_REGS];
38 /* Matze: deprecated and totally broken */
41 static void *mips_scheduler_init_graph(const list_sched_selector_t *vtab, const arch_env_t *arch_env, ir_graph *irg)
43 mips_sched_env_t *sched_env = xmalloc(sizeof(sched_env[0]));
44 memset(sched_env, 0, sizeof(sched_env[0]));
46 sched_env->arch_env = arch_env;
47 sched_env->div_set = new_pset(pset_default_ptr_cmp, 4);
52 static void mips_scheduler_finish_graph(void* graph_env)
54 mips_sched_env_t *sched_env = (mips_sched_env_t*) graph_env;
55 del_pset(sched_env->div_set);
58 static void *mips_scheduler_init_block(void *graph_env, ir_node *block)
60 mips_sched_env_t *sched_env = (mips_sched_env_t*) graph_env;
61 assert(pset_count(sched_env->div_set) == 0);
63 // TODO later we might have blocks that don't end in a jump
64 memset(&sched_env->busy_registers, 0, sizeof(sched_env->busy_registers));
65 sched_env->block = block;
66 sched_env->last_nop = NULL;
70 static void mips_scheduler_finish_block(void* graph_env)
72 mips_sched_env_t *sched_env = (mips_sched_env_t*) graph_env;
73 // attach last nop to end node (so that firm doesn't discard it)
74 if(sched_env->last_nop != NULL) {
75 ir_node* end = get_irg_end(get_irn_irg(sched_env->block));
79 sched_env->block = NULL;
82 static int mips_scheduler_to_appear_in_schedule(void *block_env, const ir_node *irn)
84 return is_mips_irn(irn) && !is_mips_zero(irn) && !is_mips_reinterpret_conv(irn) && !is_mips_fallthrough(irn);
87 static void mips_collect_mflohis(pset* set, ir_node* node) {
88 // construct a list of nodes that need to be scheduled before
89 // we are allowed to schedule another div or mul instruction
90 const ir_edge_t *edge, *edge2;
92 if(is_mips_div(node)) {
93 foreach_out_edge(node, edge) {
94 const ir_node* node2 = get_edge_src_irn(edge);
96 assert(is_Proj(node2));
97 foreach_out_edge(node2, edge2) {
98 const ir_node* node3 = get_edge_src_irn(edge2);
99 if(is_mips_mfhi(node3) || is_mips_mflo(node3))
100 pset_insert_ptr(set, node3);
103 } else if(is_mips_mult(node)) {
104 foreach_out_edge(node, edge) {
105 const ir_node* node2 = get_edge_src_irn(edge);
107 if(is_mips_mfhi(node2) || is_mips_mflo(node2))
108 pset_insert_ptr(set, node2);
113 static int mips_scheduler_node_allowed(mips_sched_env_t *sched_env, ir_node* node)
115 if(pset_count(sched_env->div_set) != 0 && (is_mips_div(node) || is_mips_mult(node))) {
122 static ir_node *mips_scheduler_select(void *block_env, nodeset *ready_set, nodeset *live_set)
124 mips_sched_env_t *sched_env = (mips_sched_env_t*) block_env;
125 const arch_env_t *arch_env = (const arch_env_t*) sched_env->arch_env;
126 ir_node *node = NULL;
127 ir_node *block = sched_env->block;
128 ir_node *condjmp = NULL;
129 ir_graph *irg = get_irn_irg(block);
130 int have_non_branch_nodes = 0;
132 // test all nodes in the ready set and take the first non-branch that
134 for (node = nodeset_first(ready_set); node != NULL; node = nodeset_next(ready_set)) {
135 if (arch_irn_class_is(arch_env, node, branch)) {
136 if (is_irn_forking(node))
141 have_non_branch_nodes = 1;
143 if (mips_scheduler_node_allowed(sched_env, node))
145 nodeset_break(ready_set);
147 // TODO update busy_registers
149 if (is_mips_div(node) || is_mips_mult(node)) {
150 mips_collect_mflohis(sched_env->div_set, node);
151 } else if(is_mips_mflo(node) || is_mips_mfhi(node)) {
152 pset_remove_ptr(sched_env->div_set, node);
159 // if we arrive here no non-branch node was found that we can emit
161 // return a branch if there are just branches left
162 if(!have_non_branch_nodes) {
163 // schedule conditional branches before non-conditional ones
164 if(condjmp != NULL) {
167 node = nodeset_first(ready_set);
168 assert(arch_irn_class_is(arch_env, node, branch));
169 nodeset_break(ready_set);
174 node = new_rd_mips_nop(NULL, irg, block, mode_M);
182 * Returns the reg_pressure scheduler with to_appear_in_schedule() overloaded
184 const list_sched_selector_t *mips_get_list_sched_selector(const void *self, list_sched_selector_t *selector)
187 memset(&mips_sched_selector, 0, sizeof(mips_sched_selector));
188 mips_sched_selector.init_graph = mips_scheduler_init_graph;
189 mips_sched_selector.init_block = mips_scheduler_init_block;
190 mips_sched_selector.select = mips_scheduler_select;
191 mips_sched_selector.to_appear_in_schedule = mips_scheduler_to_appear_in_schedule;
192 mips_sched_selector.finish_block = mips_scheduler_finish_block;
193 mips_sched_selector.finish_graph = mips_scheduler_finish_graph;
194 //return &mips_sched_selector;
199 const ilp_sched_selector_t *mips_get_ilp_sched_selector(const void *self) {