re PR tree-optimization/82381 (internal compiler error: qsort checking failed)

	PR tree-optimization/82381
	* tree-ssa-reassoc.c (sort_by_operand_rank): Don't check
	stmt_to_insert nor wheather SSA_NAMEs are default defs.
	Return 1 or -1 if one of bba and bbb is NULL. If bb_rank is equal,
	fallthrough into reassoc_stmt_dominates_stmt_p.

	* gcc.c-torture/compile/pr82381.c: New test.

From-SVN: r253379

4 files changed, 47 insertions, 19 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 934dd76..25dcf02 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,11 @@
 2017-10-03  Jakub Jelinek  <jakub@redhat.com>
 
+	PR tree-optimization/82381
+	* tree-ssa-reassoc.c (sort_by_operand_rank): Don't check
+	stmt_to_insert nor wheather SSA_NAMEs are default defs.
+	Return 1 or -1 if one of bba and bbb is NULL. If bb_rank is equal,
+	fallthrough into reassoc_stmt_dominates_stmt_p.
+
 	PR target/82386
 	* combine.c (combine_instructions): Don't combine in unreachable
 	basic blocks.
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 74023ab..70fde54 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 2017-10-03  Jakub Jelinek  <jakub@redhat.com>
 
+	PR tree-optimization/82381
+	* gcc.c-torture/compile/pr82381.c: New test.
+
 	PR target/82386
 	* gcc.dg/pr82386.c: New test.
 
diff --git a/gcc/testsuite/gcc.c-torture/compile/pr82381.c b/gcc/testsuite/gcc.c-torture/compile/pr82381.c
new file mode 100644
index 0000000..3ff2c3a
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr82381.c
@@ -0,0 +1,18 @@
+/* PR tree-optimization/82381 */
+/* { dg-do compile } */
+
+signed char b, h;
+unsigned short c, e;
+short int d, f, g;
+
+void
+foo ()
+{
+  if (h)
+    {
+      short a = -(d + c - b);
+      f = e - a - -d;
+    }
+  if (c)
+    g = 0;
+}
diff --git a/gcc/tree-ssa-reassoc.c b/gcc/tree-ssa-reassoc.c
index b2d0f57..eff76d1 100644
--- a/gcc/tree-ssa-reassoc.c
+++ b/gcc/tree-ssa-reassoc.c
@@ -514,36 +514,37 @@ sort_by_operand_rank (const void *pa, const void *pb)
       && TREE_CODE (oea->op) == SSA_NAME
       && TREE_CODE (oeb->op) == SSA_NAME)
     {
-      /* As SSA_NAME_VERSION is assigned pretty randomly, because we reuse
-	 versions of removed SSA_NAMEs, so if possible, prefer to sort
-	 based on basic block and gimple_uid of the SSA_NAME_DEF_STMT.
-	 See PR60418.  */
-      if (!SSA_NAME_IS_DEFAULT_DEF (oea->op)
-	  && !SSA_NAME_IS_DEFAULT_DEF (oeb->op)
-	  && !oea->stmt_to_insert
-	  && !oeb->stmt_to_insert
-	  && SSA_NAME_VERSION (oeb->op) != SSA_NAME_VERSION (oea->op))
+      if (SSA_NAME_VERSION (oeb->op) != SSA_NAME_VERSION (oea->op))
 	{
+	  /* As SSA_NAME_VERSION is assigned pretty randomly, because we reuse
+	     versions of removed SSA_NAMEs, so if possible, prefer to sort
+	     based on basic block and gimple_uid of the SSA_NAME_DEF_STMT.
+	     See PR60418.  */
 	  gimple *stmta = SSA_NAME_DEF_STMT (oea->op);
 	  gimple *stmtb = SSA_NAME_DEF_STMT (oeb->op);
 	  basic_block bba = gimple_bb (stmta);
 	  basic_block bbb = gimple_bb (stmtb);
 	  if (bbb != bba)
 	    {
+	      /* One of the SSA_NAMEs can be defined in oeN->stmt_to_insert
+		 but the other might not.  */
+	      if (!bba)
+		return 1;
+	      if (!bbb)
+		return -1;
+	      /* If neither is, compare bb_rank.  */
 	      if (bb_rank[bbb->index] != bb_rank[bba->index])
 		return bb_rank[bbb->index] - bb_rank[bba->index];
 	    }
-	  else
-	    {
-	      bool da = reassoc_stmt_dominates_stmt_p (stmta, stmtb);
-	      bool db = reassoc_stmt_dominates_stmt_p (stmtb, stmta);
-	      if (da != db)
-		return da ? 1 : -1;
-	    }
-	}
 
-      if (SSA_NAME_VERSION (oeb->op) != SSA_NAME_VERSION (oea->op))
-	return SSA_NAME_VERSION (oeb->op) > SSA_NAME_VERSION (oea->op) ? 1 : -1;
+	  bool da = reassoc_stmt_dominates_stmt_p (stmta, stmtb);
+	  bool db = reassoc_stmt_dominates_stmt_p (stmtb, stmta);
+	  if (da != db)
+	    return da ? 1 : -1;
+
+	  return (SSA_NAME_VERSION (oeb->op) > SSA_NAME_VERSION (oea->op)
+		  ? 1 : -1);
+	}
       else
 	return oeb->id > oea->id ? 1 : -1;
     }