re PR rtl-optimization/80747 (gcc.dg/tree-ssa/tailrecursion-4.c fails with ICE…

re PR rtl-optimization/80747 (gcc.dg/tree-ssa/tailrecursion-4.c fails with ICE when compiled with options "-fprofile-use -freorder-blocks-and-partition")

	PR rtl-optimization/80747
	PR rtl-optimization/83512
	* cfgrtl.c (force_nonfallthru_and_redirect): When splitting
	succ edge from ENTRY, copy partition from e->dest to the newly
	created bb.
	* bb-reorder.c (reorder_basic_blocks_simple): If last_tail is
	ENTRY, use BB_PARTITION of its successor block as current_partition.
	Don't copy partition when splitting succ edge from ENTRY.

	* gcc.dg/pr80747.c: New test.
	* gcc.dg/pr83512.c: New test.

From-SVN: r255954

gcc/ChangeLog

 2017-12-21  Jakub Jelinek  <jakub@redhat.com>
 
+	PR rtl-optimization/80747
+	PR rtl-optimization/83512
+	* cfgrtl.c (force_nonfallthru_and_redirect): When splitting
+	succ edge from ENTRY, copy partition from e->dest to the newly
+	created bb.
+	* bb-reorder.c (reorder_basic_blocks_simple): If last_tail is
+	ENTRY, use BB_PARTITION of its successor block as current_partition.
+	Don't copy partition when splitting succ edge from ENTRY.
+
 	PR tree-optimization/83523
 	* tree-ssa-math-opts.c (is_widening_mult_p): Return false if
 	for INTEGER_TYPE TYPE_OVERFLOW_TRAPS.

gcc/bb-reorder.c

@@ -2405,7 +2405,10 @@ reorder_basic_blocks_simple (void)
 
   basic_block last_tail = (basic_block) ENTRY_BLOCK_PTR_FOR_FN (cfun)->aux;
 
-  int current_partition = BB_PARTITION (last_tail);
+  int current_partition
+    = BB_PARTITION (last_tail == ENTRY_BLOCK_PTR_FOR_FN (cfun)
+		    ? EDGE_SUCC (ENTRY_BLOCK_PTR_FOR_FN (cfun), 0)->dest
+		    : last_tail);
   bool need_another_pass = true;
 
   for (int pass = 0; pass < 2 && need_another_pass; pass++)
@@ -2446,7 +2449,6 @@ reorder_basic_blocks_simple (void)
     {
       force_nonfallthru (e);
       e->src->aux = ENTRY_BLOCK_PTR_FOR_FN (cfun)->aux;
-      BB_COPY_PARTITION (e->src, e->dest);
     }
 }
 

gcc/cfgrtl.c

@@ -1534,6 +1534,9 @@ force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label)
 					       ENTRY_BLOCK_PTR_FOR_FN (cfun));
 	  bb->count = ENTRY_BLOCK_PTR_FOR_FN (cfun)->count;
 
+	  /* Make sure new block ends up in correct hot/cold section.  */
+	  BB_COPY_PARTITION (bb, e->dest);
+
 	  /* Change the existing edge's source to be the new block, and add
 	     a new edge from the entry block to the new block.  */
 	  e->src = bb;

gcc/testsuite/ChangeLog

 2017-12-21  Jakub Jelinek  <jakub@redhat.com>
 
+	PR rtl-optimization/80747
+	PR rtl-optimization/83512
+	* gcc.dg/pr80747.c: New test.
+	* gcc.dg/pr83512.c: New test.
+
 	PR tree-optimization/83523
 	* g++.dg/tree-ssa/pr83523.C: New test.
 

gcc/testsuite/gcc.dg/pr80747.c

+/* PR rtl-optimization/80747 */
+/* { dg-do compile } */
+/* { dg-options "-fprofile-use -freorder-blocks-and-partition -O1 -foptimize-sibling-calls" } */
+
+int
+foo (int a)
+{
+  int r;
+  if (a & 1)
+    r = foo (a - 1);
+  else if (a)
+    r = foo (a - 2);
+  else
+    return 0;
+  if (r)
+    r = r;
+  return r;
+}

gcc/testsuite/gcc.dg/pr83512.c

+/* PR rtl-optimization/83512 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -freorder-blocks-algorithm=simple" } */
+
+int a;
+
+void
+foo (int *x)
+{
+  for (;;)
+    {
+      for (*x = 0; *x < 1; *x++)
+	;
+      ++a;
+    }
+}