procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Adjust testcase for O2 vectorization enabling

Browse source 
This issue was observed in rs6000 specific PR102658 as well.

I've looked into it a bit, it's caused by the "conditional store replacement" which
is originally disabled without vectorization as below code.

  /* If either vectorization or if-conversion is disabled then do
     not sink any stores.  */
  if (param_max_stores_to_sink == 0
      || (!flag_tree_loop_vectorize && !flag_tree_slp_vectorize)
      || !flag_tree_loop_if_convert)
    return false;

The new change makes the innermost loop look like

for (int c1 = 0; c1 <= 1499; c1 += 1) {
  if (c1 <= 500) {
     S_10(c0, c1);
  } else {
      S_9(c0, c1);
  }
  S_11(c0, c1);
}

and can not be splitted as:

for (int c1 = 0; c1 <= 500; c1 += 1)
  S_10(c0, c1);

for (int c1 = 501; c1 <= 1499; c1 += 1)
  S_9(c0, c1);

So instead of disabling vectorization, could we just disable this cs replacement
with parameter "--param max-stores-to-sink=0"?

I tested this proposal on ppc64le, it should work as well.

2021-10-11  Kewen Lin  <linkw@linux.ibm.com>

libgomp/ChangeLog:

	* testsuite/libgomp.graphite/force-parallel-8.c: Add --param max-stores-to-sink=0.
This commit is contained in:
liuhongt 2021-10-11 10:05:03 +08:00
parent 82bc9355ee
commit d61ce6ab04
1 changed files with 1 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
libgomp/testsuite/libgomp.graphite/force-parallel-8.c
View file

@ -1,4 +1,4 @@
/* { dg-additional-options "-fdisable-tree-thread1 -fdisable-tree-vrp-thread1" } */
/* { dg-additional-options "-fdisable-tree-thread1 -fdisable-tree-vrp-thread1 --param max-stores-to-sink=0" } */
#define N 1500