From: Richard Biener <rguenther@suse.de>
Date: Wed, 17 Apr 2024 11:20:40 +0000 (+0200)
Subject: Avoid re-allocating vector
X-Git-Tag: basepoints/gcc-16~9273
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=cb4e2685a3e73474246adda356595f72fcd43827;p=thirdparty%2Fgcc.git

Avoid re-allocating vector

The following avoids re-allocating the var map BB vector by
pre-allocating it to the exact size needed when operating on the
whole function.

	* tree-ssa-live.cc (init_var_map): Pre-allocate vec_bbs vector
	to the correct size and use quick_push.
---

diff --git a/gcc/tree-ssa-live.cc b/gcc/tree-ssa-live.cc
index fa6be2fced3..e6ae551a457 100644
--- a/gcc/tree-ssa-live.cc
+++ b/gcc/tree-ssa-live.cc
@@ -113,8 +113,10 @@ init_var_map (int size, class loop *loop, bitmap bitint)
       map->outofssa_p = bitint == NULL;
       map->bitint = bitint;
       basic_block bb;
+      map->vec_bbs.reserve_exact (n_basic_blocks_for_fn (cfun)
+				  - NUM_FIXED_BLOCKS);
       FOR_EACH_BB_FN (bb, cfun)
-	map->vec_bbs.safe_push (bb);
+	map->vec_bbs.quick_push (bb);
     }
   return map;
 }