diff options
| author | Jan Hubicka <hubicka@ucw.cz> | 2016-06-08 16:11:51 +0200 |
|---|---|---|
| committer | Jan Hubicka <hubicka@gcc.gnu.org> | 2016-06-08 14:11:51 +0000 |
| commit | 568876dc709a2ee474d321c0f36eb81684cc5b9b (patch) | |
| tree | 91aebe6452474922006a1d37af8afb3dfbac16d0 /gcc/tree-ssa-loop-ch.c | |
| parent | b2ae281460cad49e85ba533aef075685ed5430ea (diff) | |
invoke.texi (max-loop-headers-insns): Document.
* invoke.texi (max-loop-headers-insns): Document.
* params.def (PARAM_MAX_LOOP_HEADER_INSNS): New.
* tree-ssa-loop-ch.c (should_duplicate_loop_header_p): Update comment.
(ch_base::copy_headers): Use PARAM_MAX_LOOP_HEADER_INSNS.
From-SVN: r237219
Diffstat (limited to 'gcc/tree-ssa-loop-ch.c')
| -rw-r--r-- | gcc/tree-ssa-loop-ch.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/gcc/tree-ssa-loop-ch.c b/gcc/tree-ssa-loop-ch.c index 0ddbda6da7e..9a8136968de 100644 --- a/gcc/tree-ssa-loop-ch.c +++ b/gcc/tree-ssa-loop-ch.c @@ -33,6 +33,7 @@ along with GCC; see the file COPYING3. If not see #include "tree-inline.h" #include "tree-ssa-scopedtables.h" #include "tree-ssa-threadedge.h" +#include "params.h" /* Duplicates headers of loops if they are small enough, so that the statements in the loop body are always executed when the loop is entered. This @@ -106,8 +107,7 @@ should_duplicate_loop_header_p (basic_block header, struct loop *loop, return false; } - /* Approximately copy the conditions that used to be used in jump.c -- - at most 20 insns and no calls. */ + /* Count number of instructions and punt on calls. */ for (bsi = gsi_start_bb (header); !gsi_end_p (bsi); gsi_next (&bsi)) { last = gsi_stmt (bsi); @@ -290,8 +290,8 @@ ch_base::copy_headers (function *fun) FOR_EACH_LOOP (loop, 0) { - /* Copy at most 20 insns. */ - int limit = 20; + int initial_limit = PARAM_VALUE (PARAM_MAX_LOOP_HEADER_INSNS); + int remaining_limit = initial_limit; if (dump_file && (dump_flags & TDF_DETAILS)) fprintf (dump_file, "Analyzing loop %i\n", loop->num); @@ -313,7 +313,7 @@ ch_base::copy_headers (function *fun) exit = NULL; n_bbs = 0; - while (should_duplicate_loop_header_p (header, loop, &limit)) + while (should_duplicate_loop_header_p (header, loop, &remaining_limit)) { /* Find a successor of header that is inside a loop; i.e. the new header after the condition is copied. */ @@ -333,7 +333,8 @@ ch_base::copy_headers (function *fun) fprintf (dump_file, "Duplicating header of the loop %d up to edge %d->%d," " %i insns.\n", - loop->num, exit->src->index, exit->dest->index, 20 - limit); + loop->num, exit->src->index, exit->dest->index, + initial_limit - remaining_limit); /* Ensure that the header will have just the latch as a predecessor inside the loop. */ |