On Wed, 1 Feb 2017, Richard Biener wrote:
> Applied as follows, bootstrapped & tested on x86_64-unknown-linux-gnu.
And as shown by the new testcase (ICEing on the gcc-6-branch only) the
fix is not enough as breadth merging of loop and loop->next may pull in
other loops into the region. Eventually this also shows that only
trying to merge loop with loop->next may not find all valid scops
as loop and loop->next->next may eventually be successfully merged
(inner loops of a loop are not sorted in any particular way, SCoP
dection seems to assume dominance order).
Bootstrap / regtest running on x86_64-unknown-linux-gnu.
Thanks,
Richard.
2017-02-07 Richard Biener <rguent...@suse.de>
PR tree-optimization/71824
* graphite-scop-detection.c (scop_detection::build_scop_breadth):
Check all loops contained in the merged region.
* gcc.dg/graphite/pr71824-2.c: New testcase.
Index: gcc/graphite-scop-detection.c
===================================================================
--- gcc/graphite-scop-detection.c (revision 245243)
+++ gcc/graphite-scop-detection.c (working copy)
@@ -905,9 +905,19 @@ scop_detection::build_scop_breadth (sese
sese_l combined = merge_sese (s1, s2);
- if (combined
- && loop_is_valid_in_scop (loop, combined)
- && loop_is_valid_in_scop (loop->next, combined))
+ /* Combining adjacent loops may add unrelated loops into the
+ region so we have to check all sub-loops of the outer loop
+ that are in the combined region. */
+ if (combined)
+ for (l = loop_outer (loop)->inner; l; l = l->next)
+ if (bb_in_sese_p (l->header, combined)
+ && ! loop_is_valid_in_scop (l, combined))
+ {
+ combined = invalid_sese;
+ break;
+ }
+
+ if (combined)
s1 = combined;
else
add_scop (s2);
Index: gcc/testsuite/gcc.dg/graphite/pr71824-2.c
===================================================================
--- gcc/testsuite/gcc.dg/graphite/pr71824-2.c (nonexistent)
+++ gcc/testsuite/gcc.dg/graphite/pr71824-2.c (working copy)
@@ -0,0 +1,34 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -floop-nest-optimize" } */
+
+typedef struct { float x1; } bx;
+typedef struct {
+ int w;
+ short o;
+} T2P;
+T2P a;
+int b;
+void fn2();
+void fn3(bx*,short);
+void fn1() {
+ unsigned i = 0;
+ int c;
+ bx *d;
+ bx **h;
+ if (b == 0) {
+ fn2();
+ return;
+ }
+ for (; c; c++)
+ for (; i < 100; i++) {
+ d = h[i];
+ d->x1 = a.w;
+ }
+ for (; i < 100; i++) {
+ d = h[i];
+ d->x1 = a.w;
+ }
+ if (a.o)
+ for (; b;)
+ fn3(d, a.o);
+}
