X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbespill.h;h=84f0457f3b0b072b5a6ed7d618e8f1c011694259;hb=d07cec1341e61a5321ec44d93455bbbac312be75;hp=e53ff0ac1bff5d1d7ccce1523f9d7a24e4b5f3f8;hpb=ae515d01cd46334273438ce4019847f4ba05ab3d;p=libfirm

diff --git a/ir/be/bespill.h b/ir/be/bespill.h
index e53ff0ac1..84f0457f3 100644
--- a/ir/be/bespill.h
+++ b/ir/be/bespill.h
@@ -19,7 +19,8 @@
 
 /**
  * @file
- * @brief       Main spill driver.
+ * @brief       higher level abstraction for the creation of spill and reload
+ *              instructions and rematerialisation of values.
  * @author      Daniel Grund, Sebastian Hack, Matthias Braun
  * @date		29.09.2005
  * @version     $Id$
@@ -56,22 +57,25 @@ void be_delete_spill_env(spill_env_t *senv);
  * @param to_spill    The node which is about to be spilled
  * @param before      The node before the reload should be added
  * @param reload_cls  The register class the reloaded value will be put into
- * @param allow_remat Set to 1 if the node may be rematerialized instead of reloaded
+ * @param allow_remat Set to 1 if the node may be rematerialized instead of
+ *                    reloaded
  */
 void be_add_reload(spill_env_t *senv, ir_node *to_spill, ir_node *before,
-	const arch_register_class_t *reload_cls, int allow_remat);
+                   const arch_register_class_t *reload_cls, int allow_remat);
 
 /**
  * Analog to be_add_reload, but places the reload "on an edge" between 2 blocks
  * @see be_add_reload
  */
-void be_add_reload_on_edge(spill_env_t *senv, ir_node *to_spill, ir_node *bl, int pos,
-	const arch_register_class_t *reload_cls, int allow_remat);
+void be_add_reload_on_edge(spill_env_t *senv, ir_node *to_spill, ir_node *bl,
+                           int pos, const arch_register_class_t *reload_cls,
+                           int allow_remat);
 
 /**
  * Analog to be_add_reload but adds an already created rematerialized node.
  */
-void be_add_remat(spill_env_t *env, ir_node *to_spill, ir_node *before, ir_node *rematted_node);
+void be_add_remat(spill_env_t *env, ir_node *to_spill, ir_node *before,
+                  ir_node *rematted_node);
 
 /**
  * The main function that places real spills/reloads (or rematerializes values)
@@ -89,18 +93,28 @@ void be_insert_spills_reloads(spill_env_t *senv);
  */
 void be_spill_phi(spill_env_t *env, ir_node *node);
 
+/**
+ * Returns the estimated costs if a node would ge spilled. This does only return
+ * the costs for the spill instructions, not the costs for needed reload
+ * instructions. The value is weighted by the estimated execution frequency of
+ * the spill.
+ */
+double be_get_spill_costs(spill_env_t *env, ir_node *to_spill, ir_node *after);
+
 /**
  * Returns the estimated costs if a node would get reloaded at a specific place
- * This usually returns the cost of spill + reload operation. But might return
- * smaller values if the value has already been spilled in a former run or
- * when it is possible to rematerialize the value.
+ * This returns the costs for a reload instructions, or when possible the costs
+ * for a rematerialisation. The value is weighted by the estimated execution
+ * frequency of the reload/rematerialisation.
  */
-int be_get_reload_costs(spill_env_t *env, ir_node *to_spill, ir_node *before);
+double be_get_reload_costs(spill_env_t *env, ir_node *to_spill,
+                           ir_node *before);
 
 /**
  * Analog to be_get_reload_costs but returns the cost if the reload would be
  * placed "on an edge" between 2 blocks
  */
-int be_get_reload_costs_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block, int pos);
+double be_get_reload_costs_on_edge(spill_env_t *env, ir_node *to_spill,
+                                   ir_node *block, int pos);
 
-#endif /* FIRM_BE_BESPILL_H */
+#endif