re PR bootstrap/83396 (Bootstrap failures with Statement Frontiers)

	PR bootstrap/83396
	* var-tracking.c (vt_initialize): Ignore non-DEBUG_INSNs outside of
	basic blocks.  Assert debug bind insns don't appear outside of bbs,
	don't reset them.  Assert insns without BLOCK_FOR_INSN are outside of
	bb.  Simplify.

	* gcc.dg/pr83396.c: New test.

From-SVN: r255627

gcc/ChangeLog

 2017-12-14  Jakub Jelinek  <jakub@redhat.com>
 
+	PR bootstrap/83396
+	* var-tracking.c (vt_initialize): Ignore non-DEBUG_INSNs outside of
+	basic blocks.  Assert debug bind insns don't appear outside of bbs,
+	don't reset them.  Assert insns without BLOCK_FOR_INSN are outside of
+	bb.  Simplify.
+
 	PR tree-optimization/83198
 	* gimple-ssa-sprintf.c (format_floating): Set type solely based on
 	dir.modifier, regardless of TREE_TYPE (arg).  Assume non-REAL_CST

gcc/testsuite/ChangeLog

 2017-12-14  Jakub Jelinek  <jakub@redhat.com>
 
+	PR bootstrap/83396
+	* gcc.dg/pr83396.c: New test.
+
 	PR tree-optimization/83198
 	* gcc.dg/pr83198.c: New test.
 	* gcc.dg/tree-ssa/pr83198.c: New test.

gcc/testsuite/gcc.dg/pr83396.c

+/* PR bootstrap/83396 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -g" } */
+
+int bar (int);
+int baz (int);
+
+int
+foo (int x)
+{
+  return bar (x) || baz (x) != 0;
+}

gcc/var-tracking.c

@@ -10157,25 +10157,31 @@ vt_initialize (void)
 	     insns that might be before it too.  Unfortunately,
 	     BB_HEADER and BB_FOOTER are not set while we run this
 	     pass.  */
-	  insn = get_first_insn (bb);
-	  for (rtx_insn *next;
-	       insn != BB_HEAD (bb->next_bb)
-		 ? next = NEXT_INSN (insn), true : false;
+	  rtx_insn *next;
+	  bool outside_bb = true;
+	  for (insn = get_first_insn (bb); insn != BB_HEAD (bb->next_bb);
 	       insn = next)
 	    {
+	      if (insn == BB_HEAD (bb))
+		outside_bb = false;
+	      else if (insn == NEXT_INSN (BB_END (bb)))
+		outside_bb = true;
+	      next = NEXT_INSN (insn);
 	      if (INSN_P (insn))
 		{
+		  if (outside_bb)
+		    {
+		      /* Ignore non-debug insns outside of basic blocks.  */
+		      if (!DEBUG_INSN_P (insn))
+			continue;
+		      /* Debug binds shouldn't appear outside of bbs.  */
+		      gcc_assert (!DEBUG_BIND_INSN_P (insn));
+		    }
 		  basic_block save_bb = BLOCK_FOR_INSN (insn);
 		  if (!BLOCK_FOR_INSN (insn))
 		    {
+		      gcc_assert (outside_bb);
 		      BLOCK_FOR_INSN (insn) = bb;
-		      gcc_assert (DEBUG_INSN_P (insn));
-		      /* Reset debug insns between basic blocks.
-			 Their location is not reliable, because they
-			 were probably not maintained up to date.  */
-		      if (DEBUG_BIND_INSN_P (insn))
-			INSN_VAR_LOCATION_LOC (insn)
-			  = gen_rtx_UNKNOWN_VAR_LOC ();
 		    }
 		  else
 		    gcc_assert (BLOCK_FOR_INSN (insn) == bb);