X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbechordal.c;h=0d4c145ae695b5c8827196aa93ae7c51d023d885;hb=e91ddc5da31fa23e1d1fb94374c54cba5772e3fd;hp=52c4e497a8740927747e7706cd38c28d365c8d56;hpb=51db25711d0d37d9a45cb707e772bcb9c74c44b6;p=libfirm

diff --git a/ir/be/bechordal.c b/ir/be/bechordal.c
index 52c4e497a..0d4c145ae 100644
--- a/ir/be/bechordal.c
+++ b/ir/be/bechordal.c
@@ -475,12 +475,13 @@ static ir_node *pre_process_constraints(be_chordal_alloc_env_t *alloc_env, insn_
 	return perm;
 }
 
-static ir_node *handle_constraints(be_chordal_alloc_env_t *alloc_env, ir_node *irn)
+static ir_node *handle_constraints(be_chordal_alloc_env_t *alloc_env, ir_node *irn, int *silent)
 {
 	be_chordal_env_t *env  = alloc_env->chordal_env;
 	void *base             = obstack_base(&env->obst);
 	insn_t *insn           = scan_insn(alloc_env, irn, &env->obst);
 	ir_node *res           = insn->next_insn;
+	int be_silent          = *silent;
 
 	if(insn->pre_colored) {
 		int i;
@@ -488,7 +489,17 @@ static ir_node *handle_constraints(be_chordal_alloc_env_t *alloc_env, ir_node *i
 			pset_insert_ptr(alloc_env->pre_colored, insn->ops[i].carrier);
 	}
 
-	if(be_is_Perm(irn) || be_is_RegParams(irn) || (be_is_Barrier(irn) && !insn->in_constraints))
+	/*
+		If the current node is a barrier toggle the silent flag.
+		If we are in the start block, we are ought to be silent at the beginning,
+		so the toggling activates the constraint handling but skips the barrier.
+		If we are in the end block we handle the in requirements of the barrier
+		and set the rest to silent.
+	*/
+	if(be_is_Barrier(irn))
+		*silent = !*silent;
+
+	if(be_silent)
 		goto end;
 
 	/*
@@ -563,7 +574,7 @@ static ir_node *handle_constraints(be_chordal_alloc_env_t *alloc_env, ir_node *i
 
 				assert(is_Proj(proj));
 
-				if(values_interfere(proj, irn)) {
+				if(values_interfere(proj, irn) && !pmap_contains(partners, proj)) {
 					assert(n_alloc < n_regs);
 					alloc_nodes[n_alloc] = proj;
 					pmap_insert(partners, proj, NULL);
@@ -646,20 +657,32 @@ end:
 
 /**
  * Handle constraint nodes in each basic block.
- * be_insert_constr_perms() inserts Perm nodes which perm
+ * handle_constraints() inserts Perm nodes which perm
  * over all values live at the constrained node right in front
  * of the constrained node. These Perms signal a constrained node.
- * For further comments, refer to handle_constraints_at_perm().
+ * For further comments, refer to handle_constraints().
  */
 static void constraints(ir_node *bl, void *data)
 {
-	firm_dbg_module_t *dbg      = firm_dbg_register("firm.be.chordal.constr");
 	be_chordal_alloc_env_t *env = data;
 	arch_env_t *arch_env        = env->chordal_env->birg->main_env->arch_env;
+	FIRM_DBG_REGISTER(firm_dbg_module_t *dbg, "firm.be.chordal.constr");
+
+	/*
+		Start silent in the start block.
+		The silence remains until the first barrier is seen.
+		Each other block is begun loud.
+	*/
+	int silent                  = bl == get_irg_start_block(get_irn_irg(bl));
 	ir_node *irn;
 
+	/*
+		If the block is the start block search the barrier and
+		start handling constraints from there.
+	*/
+
 	for(irn = sched_first(bl); !sched_is_end(irn);) {
-		irn = handle_constraints(env, irn);
+		irn = handle_constraints(env, irn, &silent);
 	}
 }
 
@@ -902,7 +925,7 @@ void be_ra_chordal_color(be_chordal_env_t *chordal_env)
 	env.in_colors     = bitset_alloca(colors_n);
 	env.ignore_regs   = bitset_alloca(colors_n);
 	env.pre_colored   = pset_new_ptr_default();
-	env.constr_dbg    = firm_dbg_register("firm.be.chordal.constr");
+	FIRM_DBG_REGISTER(env.constr_dbg, "firm.be.chordal.constr");
 
 	for(i = 0; i < colors_n; ++i)
 		if(arch_register_type_is(&chordal_env->cls->regs[i], ignore))