contrib/gcc/loop-unroll.c

38    optimizations on innermost loops (with single exception) because
47    -- complete peeling of once-rolling loops; this is the above mentioned
50    -- complete peeling of loops that roll (small) constant times.
51    -- simple peeling of first iterations of loops that do not roll much
53    -- unrolling of loops that roll constant times; this is almost always
55    -- unrolling of loops that roll number of times that we can compute
58    -- simple unrolling of remaining loops; this is performed only if we
117 static void decide_unrolling_and_peeling (struct loops *, int);
118 static void peel_loops_completely (struct loops *, int);
125 static void peel_loop_simple (struct loops *, struct loop *);
126 static void peel_loop_completely (struct loops *, struct loop *);
127 static void unroll_loop_stupid (struct loops *, struct loop *);
128 static void unroll_loop_constant_iterations (struct loops *, struct loop *);
129 static void unroll_loop_runtime_iterations (struct loops *, struct loop *);
145 unroll_and_peel_loops (struct loops *loops, int flags)
152   peel_loops_completely (loops, flags);
155   decide_unrolling_and_peeling (loops, flags);
157   loop = loops->tree_root;
161   /* Scan the loops, inner ones first.  */
162   while (loop != loops->tree_root)
181 	  peel_loop_simple (loops, loop);
184 	  unroll_loop_constant_iterations (loops, loop);
187 	  unroll_loop_runtime_iterations (loops, loop);
190 	  unroll_loop_stupid (loops, loop);
202 	  verify_loop_structure (loops);
234 peel_loops_completely (struct loops *loops, int flags)
239   /* Scan the loops, the inner ones first.  */
240   for (i = loops->num - 1; i > 0; i--)
242       loop = loops->parray[i];
261 	  peel_loop_completely (loops, loop);
264 	  verify_loop_structure (loops);
272 decide_unrolling_and_peeling (struct loops *loops, int flags)
274   struct loop *loop = loops->tree_root, *next;
279   /* Scan the loops, inner ones first.  */
280   while (loop != loops->tree_root)
315       /* Skip non-innermost loops.  */
360   /* Check for simple loops.  */
392   /* Skip non-innermost loops.  */
430   /* Check for simple loops.  */
478 peel_loop_completely (struct loops *loops, struct loop *loop)
507 					  loops, npeel,
526 	remove_path (loops, remove_edges[i]);
535   remove_path (loops, ein);
571   /* Skip big loops.  */
579   /* Check for simple loops.  */
661 unroll_loop_constant_iterations (struct loops *loops, struct loop *loop)
693 	 in the first copy, so that the loops that start with test
708 					      loops, exit_mod,
747 					      loops, exit_mod + 1,
774 				      loops, max_unroll,
814     remove_path (loops, remove_edges[i]);
851   /* Skip big loops.  */
859   /* Check for simple loops.  */
934 unroll_loop_runtime_iterations (struct loops *loops, struct loop *loop)
1029 				      loops, 1,
1046 					  loops, 1,
1097 				      loops, max_unroll,
1134     remove_path (loops, remove_edges[i]);
1185   /* Skip big loops.  */
1193   /* Check for simple loops.  */
1204   /* Do not simply peel loops with branches inside -- it increases number
1264 peel_loop_simple (struct loops *loops, struct loop *loop)
1281 				      loops, npeel, wont_exit,
1344   /* Skip big loops.  */
1352   /* Check for simple loops.  */
1363   /* Do not unroll loops with branches inside -- it increases number
1414 unroll_loop_stupid (struct loops *loops, struct loop *loop)
1432 				      loops, nunroll, wont_exit,