X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbespill.h;h=17eba7a2ab52fbc4546a6979fb314a632b38eae4;hb=80a6158fdd766f42ee6c508a773bc114ff1b61f3;hp=8cffc849edaae32d5e7a5d5f06f170587804adda;hpb=2c52bb5cb8c25f23843c035fdad1efb80f6417a0;p=libfirm

diff --git a/ir/be/bespill.h b/ir/be/bespill.h
index 8cffc849e..17eba7a2a 100644
--- a/ir/be/bespill.h
+++ b/ir/be/bespill.h
@@ -1,10 +1,9 @@
-/**
- * Author:      Daniel Grund, Sebastian Hack
+/*
+ * Author:      Daniel Grund, Sebastian Hack, Matthias Braun
  * Date:		29.09.2005
  * Copyright:   (c) Universitaet Karlsruhe
  * Licence:     This file protected by GPL -  GNU GENERAL PUBLIC LICENSE.
  */
-
 #ifndef BESPILL_H_
 #define BESPILL_H_
 
@@ -22,37 +21,61 @@ typedef struct _spill_env_t spill_env_t;
 
 /**
  * Creates a new spill environment.
- *
- * @param chordal
- * @param is_spilled_phi	a function that evaluates a phi node and returns true if it is a spilled phi node
- * @param data				context parameter for the is_spilled_phi function
  */
 spill_env_t *be_new_spill_env(const be_chordal_env_t *chordal);
 
 /**
- * Marks a phi-node for spilling
+ * Deletes a spill environment.
  */
-void be_spill_phi(spill_env_t *env, ir_node *node);
+void be_delete_spill_env(spill_env_t *senv);
 
 /**
- * Deletes a spill environment.
+ * Sets the debug module of a spill environment.
  */
-void be_delete_spill_env(spill_env_t *senv);
+DEBUG_ONLY(void be_set_spill_env_dbg_module(spill_env_t *env, firm_dbg_module_t *dbg));
 
-void be_add_reload(spill_env_t *senv, ir_node *to_spill, ir_node *before);
+/**
+ * Inserts a new entry into the list of reloads to place (the real nodes will
+ * be created when be_insert_spills_reloads is run). You don't have to
+ * explicitly create spill nodes, they will be created automatically after
+ * the definition of a value as soon as a reload is created. (we should add a
+ * possibility for explicit spill placement in the future)
+ */
+void be_add_reload(spill_env_t *senv, ir_node *to_spill, ir_node *before, const arch_register_class_t *reload_cls);
 
-void be_add_reload_on_edge(spill_env_t *senv, ir_node *to_spill, ir_node *bl, int pos);
+/**
+ * Analog to be_add_reload, but places the reload "on an edge" between 2 blocks
+ */
+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);
 
+/**
+ * The main function that places real spills/reloads (or rematerializes values)
+ * for all values where be_add_reload was called. It then rebuilds the
+ * SSA-form and updates liveness information
+ */
 void be_insert_spills_reloads(spill_env_t *senv);
 
 /**
- * Computes the spill offsets for all spill nodes in the irg
+ * There are 2 possibilities to spill a phi node: Only it's value, or replacing
+ * the whole phi-node with a memory phi. Normally only the value of a phi will
+ * be spilled unless you mark the phi with be_spill_phi.
+ * (Remember that each phi needs a register, so you have to spill phis when
+ *  there are more phis than registers in a block)
+ */
+void be_spill_phi(spill_env_t *env, ir_node *node);
+
+/**
+ * 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.
  */
-void be_compute_spill_offsets(be_chordal_env_t *cenv);
+int be_get_reload_costs(spill_env_t *env, ir_node *to_spill, ir_node *before);
 
 /**
- * Sets the debug module of a spill environment.
+ * Analog to be_get_reload_costs but returns the cost if the reload would be
+ * placed "on an edge" between 2 blocks
  */
-DEBUG_ONLY(void be_set_spill_env_dbg_module(spill_env_t *env, firm_dbg_module_t *dbg));
+int be_get_reload_costs_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block, int pos);
 
-#endif /* BESPILL_H_ */
+#endif