invoke.texi: Document -ftree-loop-distribution for O3.

	* doc/invoke.texi: Document -ftree-loop-distribution for O3.
	* opts.c (default_options_table): Add OPT_ftree_loop_distribution.

From-SVN: r250959

gcc/ChangeLog

+2017-08-08  Bin Cheng  <bin.cheng@arm.com>
+
+	* doc/invoke.texi: Document -ftree-loop-distribution for O3.
+	* opts.c (default_options_table): Add OPT_ftree_loop_distribution.
+
 2017-08-08  Tamar Christina  <tamar.christina@arm.com>
 
 	PR middle-end/19706

gcc/doc/invoke.texi

@@ -7248,13 +7248,20 @@ invoking @option{-O2} on programs that use computed gotos.
 @item -O3
 @opindex O3
 Optimize yet more.  @option{-O3} turns on all optimizations specified
-by @option{-O2} and also turns on the @option{-finline-functions},
-@option{-funswitch-loops}, @option{-fpredictive-commoning},
-@option{-fgcse-after-reload}, @option{-ftree-loop-vectorize},
-@option{-ftree-loop-distribute-patterns}, @option{-fsplit-paths}
-@option{-ftree-slp-vectorize}, @option{-fvect-cost-model},
-@option{-ftree-partial-pre}, @option{-fpeel-loops}
-and @option{-fipa-cp-clone} options.
+by @option{-O2} and also turns on the following optimization flags:
+@gccoptlist{-finline-functions @gol
+-funswitch-loops @gol
+-fpredictive-commoning @gol
+-fgcse-after-reload @gol
+-ftree-loop-vectorize @gol
+-ftree-loop-distribution @gol
+-ftree-loop-distribute-patterns @gol
+-fsplit-paths @gol
+-ftree-slp-vectorize @gol
+-fvect-cost-model @gol
+-ftree-partial-pre @gol
+-fpeel-loops @gol
+-fipa-cp-clone}
 
 @item -O0
 @opindex O0

gcc/opts.c

@@ -525,6 +525,7 @@ static const struct default_options default_options_table[] =
 
     /* -O3 optimizations.  */
     { OPT_LEVELS_3_PLUS, OPT_ftree_loop_distribute_patterns, NULL, 1 },
+    { OPT_LEVELS_3_PLUS, OPT_ftree_loop_distribution, NULL, 1 },
     { OPT_LEVELS_3_PLUS, OPT_fpredictive_commoning, NULL, 1 },
     { OPT_LEVELS_3_PLUS, OPT_fsplit_paths, NULL, 1 },
     /* Inlining of functions reducing size is a good idea with -Os