besched: Add be_move_after_schedule_first() to place nodes after schedule_first nodes.

ir/be/arm/arm_finish.c

@@ -81,15 +81,12 @@ static void introduce_prolog_epilog(ir_graph *irg)
 	ir_node               *start      = get_irg_start(irg);
 	ir_node               *block      = get_nodes_block(start);
 	ir_node               *initial_sp = be_get_initial_reg_value(irg, sp_reg);
-	ir_node               *schedpoint = start;
 	ir_type               *frame_type = get_irg_frame_type(irg);
 	unsigned               frame_size = get_type_size_bytes(frame_type);
 
-	while (be_is_Keep(sched_next(schedpoint)))
-		schedpoint = sched_next(schedpoint);
-
 	ir_node *const incsp = be_new_IncSP(sp_reg, block, initial_sp, frame_size, 0);
 	edges_reroute_except(initial_sp, incsp, incsp);
+	ir_node *const schedpoint = be_move_after_schedule_first(start);
 	sched_add_after(schedpoint, incsp);
 }
 

ir/be/besched.c

@@ -166,3 +166,13 @@ void be_init_sched(void)
 	be_add_module_list_opt(be_grp, "scheduler", "scheduling algorithm",
 	                       &schedulers, (void**)&scheduler);
 }
+
+ir_node *be_move_after_schedule_first(ir_node *node)
+{
+	for (;;) {
+		ir_node *const next = sched_next(node);
+		if (!arch_irn_is(next, schedule_first))
+			return node;
+		node = next;
+	}
+}

ir/be/besched.h

@@ -229,4 +229,10 @@ void be_register_scheduler(const char *name, schedule_func func);
  */
 void be_schedule_graph(ir_graph *irg);
 
+/**
+ * Return the last schedule_first node following node, if there is any, node
+ * otherwise.
+ */
+ir_node *be_move_after_schedule_first(ir_node *node);
+
 #endif

ir/be/bespillutil.c

@@ -210,22 +210,6 @@ ir_node *be_get_end_of_block_insertion_point(const ir_node *block)
 	return last;
 }
 
-/**
- * determine final spill position: it should be after all phis, keep nodes
- * and behind nodes marked as prolog
- */
-static ir_node *determine_spill_point(ir_node *const node)
-{
-	ir_node *n = skip_Proj(node);
-	while (true) {
-		ir_node *next = sched_next(n);
-		if (!is_Phi(next) && !be_is_Keep(next) && !be_is_CopyKeep(next))
-			break;
-		n = next;
-	}
-	return n;
-}
-
 /**
  * Returns the point at which you can insert a node that should be executed
  * before block @p block when coming from pred @p pos.
@@ -272,7 +256,7 @@ void be_spill_phi(spill_env_t *env, ir_node *node)
 			insert = be_get_end_of_block_insertion_point(pred_block);
 			insert = sched_prev(insert);
 		} else {
-			insert = determine_spill_point(arg);
+			insert = be_move_after_schedule_first(arg);
 		}
 		be_add_spill(env, arg, insert);
 	}
@@ -308,9 +292,7 @@ static void spill_irn(spill_env_t *env, spill_info_t *spillinfo)
 	DBG((dbg, LEVEL_1, "spilling %+F ... \n", to_spill));
 	for (spill_t *spill = spillinfo->spills; spill != NULL;
 	     spill = spill->next) {
-		ir_node *after = spill->after;
-		after = determine_spill_point(after);
-
+		ir_node *const after = be_move_after_schedule_first(spill->after);
 		spill->spill = arch_env_new_spill(env->arch_env, to_spill, after);
 		DB((dbg, LEVEL_1, "\t%+F after %+F\n", spill->spill, after));
 		env->spill_count++;
@@ -348,7 +330,7 @@ static void spill_phi(spill_env_t *env, spill_info_t *spillinfo)
 	/* override or replace spills list... */
 	ir_node *block = get_nodes_block(phi);
 	spill_t *spill = OALLOC(&env->obst, spill_t);
-	spill->after   = determine_spill_point(phi);
+	spill->after   = be_move_after_schedule_first(phi);
 	spill->spill   = be_new_Phi(block, arity, ins, mode_M, arch_no_register_req);
 	spill->next    = NULL;
 	sched_add_after(block, spill->spill);
@@ -612,7 +594,7 @@ static void determine_spill_costs(spill_env_t *env, spill_info_t *spillinfo)
 
 	/* override spillinfos or create a new one */
 	spill_t *spill = OALLOC(&env->obst, spill_t);
-	spill->after   = determine_spill_point(to_spill);
+	spill->after   = be_move_after_schedule_first(skip_Proj(to_spill));
 	spill->next    = NULL;
 	spill->spill   = NULL;
 
@@ -1186,13 +1168,8 @@ static void melt_copykeeps(constraint_env_t *cenv)
 			ir_nodeset_insert(&entry->copies, new_ck);
 
 			/* find scheduling point */
-			ir_node *sched_pt = ref_mode_T;
-			do {
-				/* just walk along the schedule until a non-Keep/CopyKeep node is found */
-				sched_pt = sched_next(sched_pt);
-			} while (be_is_Keep(sched_pt) || be_is_CopyKeep(sched_pt));
-
-			sched_add_before(sched_pt, new_ck);
+			ir_node *const sched_pt = be_move_after_schedule_first(ref_mode_T);
+			sched_add_after(sched_pt, new_ck);
 			DB((dbg_constr, LEVEL_1, "created %+F, scheduled before %+F\n", new_ck, sched_pt));
 
 			/* finally: kill the reference copykeep */

ir/be/bestate.c

@@ -110,11 +110,7 @@ static spill_info_t *create_spill(minibelady_env_t *env, ir_node *state,
 
 	ir_node *after;
 	if (sched_is_scheduled(state)) {
-		ir_node *next = state;
-		do {
-			after = next;
-			next = sched_next(after);
-		} while (is_Phi(next) || be_is_Keep(next));
+		after = be_move_after_schedule_first(state);
 	} else {
 		after = state;
 	}

ir/be/sparc/sparc_finish.c

@@ -173,7 +173,6 @@ static void sparc_introduce_prolog_epilog(ir_graph *irg)
 	be_stack_layout_t     *layout     = be_get_irg_stack_layout(irg);
 	ir_node               *block      = get_nodes_block(start);
 	ir_node               *initial_sp = be_get_initial_reg_value(irg, sp_reg);
-	ir_node               *schedpoint = start;
 	ir_type               *frame_type = get_irg_frame_type(irg);
 	unsigned               frame_size = get_type_size_bytes(frame_type);
 
@@ -183,14 +182,11 @@ static void sparc_introduce_prolog_epilog(ir_graph *irg)
 		introduce_epilog(ret);
 	}
 
-	while (be_is_Keep(sched_next(schedpoint)))
-		schedpoint = sched_next(schedpoint);
-
+	ir_node *const schedpoint = be_move_after_schedule_first(start);
 	if (!layout->sp_relative) {
 		ir_node *const save = new_bd_sparc_Save_imm(NULL, block, initial_sp, NULL, -(SPARC_MIN_STACKSIZE + frame_size));
 		arch_set_irn_register(save, sp_reg);
 		sched_add_after(schedpoint, save);
-		schedpoint = save;
 
 		edges_reroute_except(initial_sp, save, save);