re PR tree-optimization/71824 (ICE when compiling libiberty with Graphite loop optimizations)

2017-02-08  Richard Biener  <rguenther@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.

From-SVN: r245270

gcc/ChangeLog

+2017-02-08  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/71824
+	* graphite-scop-detection.c (scop_detection::build_scop_breadth):
+	Check all loops contained in the merged region.
+
 2017-02-07  Andrew Pinski  <apinski@cavium.com>
 
 	* config/aarch64/aarch64.md (popcount<mode>2): New pattern.

gcc/graphite-scop-detection.c

@@ -905,9 +905,19 @@ scop_detection::build_scop_breadth (sese_l s1, loop_p loop)
 
   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);

gcc/testsuite/ChangeLog

+2017-02-08  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/71824
+	* gcc.dg/graphite/pr71824-2.c: New testcase.
+
 2017-02-07  Andrew Pinski  <apinski@cavium.com>
 
 	* gcc.target/aarch64/popcount.c : New Testcase.

gcc/testsuite/gcc.dg/graphite/pr71824-2.c

+/* { 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);
+}