Re: [PATCH] comment precising need to use free_dominance_info

[Pierre Vittet <piervit@pvittet.com>]

[-- Attachment #1: Type: text/plain, Size: 279 bytes --]

So maybe this patch adding a comment on calculate_dominance_info is more 
adapted.

ChangeLog:
2011-05-17  Pierre Vittet<piervit@pvittet.com>

	* dominance.c (calculate_dominance_info): Add comment
	   precising when to free with free_dominance_info

contributor number: 634276


[-- Attachment #2: comment_calculate_dominance_info.diff --]
[-- Type: text/plain, Size: 768 bytes --]

Index: gcc/dominance.c
===================================================================
--- gcc/dominance.c	(revision 173830)
+++ gcc/dominance.c	(working copy)
@@ -628,8 +628,15 @@ compute_dom_fast_query (enum cdi_direction dir)
 }
 
 /* The main entry point into this module.  DIR is set depending on whether
-   we want to compute dominators or postdominators.  */
+   we want to compute dominators or postdominators.  
 
+   We try to keep dominance info alive as long as possible (to avoid
+   recomputing it often). It has to be freed with free_dominance_info when CFG
+   transformation makes it invalide. 
+   
+   post_dominance info is less often used, and should be freed after each use.
+*/
+
 void
 calculate_dominance_info (enum cdi_direction dir)
 {