re PR tree-optimization/90090 (ICE in mark_reachable_handlers, at tree-eh.c:3938 since r219202)

	PR tree-optimization/90090
	* tree-ssa-math-opts.c (is_division_by): Ignore divisions that can
	throw internally.
	(is_division_by_square): Likewise.  Formatting fix.

	* g++.dg/opt/pr90090.C: New test.

From-SVN: r270379

gcc/ChangeLog

+2019-04-16  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/90090
+	* tree-ssa-math-opts.c (is_division_by): Ignore divisions that can
+	throw internally.
+	(is_division_by_square): Likewise.  Formatting fix.
+
 2019-04-16  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/56049

gcc/testsuite/ChangeLog

+2019-04-16  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/90090
+	* g++.dg/opt/pr90090.C: New test.
+
 2019-04-16  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/56049

gcc/testsuite/g++.dg/opt/pr90090.C

+// PR tree-optimization/90090
+// { dg-do compile }
+// { dg-options "-Ofast -fno-associative-math -fsignaling-nans -fno-tree-dce -fnon-call-exceptions" }
+
+double bar (double, double, double, double, double);
+double baz ();
+
+double
+foo (double a)
+{
+  try
+    {
+      return bar (1.0/a, 2.0/a, 4.0/a, 8.0/a, 16.0/a);
+    }
+  catch (...)
+    {
+      return baz ();
+    }
+}

gcc/tree-ssa-math-opts.c

@@ -334,7 +334,8 @@ is_division_by (gimple *use_stmt, tree def)
 	 /* Do not recognize x / x as valid division, as we are getting
 	    confused later by replacing all immediate uses x in such
 	    a stmt.  */
-	 && gimple_assign_rhs1 (use_stmt) != def;
+	 && gimple_assign_rhs1 (use_stmt) != def
+	 && !stmt_can_throw_internal (cfun, use_stmt);
 }
 
 /* Return TRUE if USE_STMT is a multiplication of DEF by A.  */
@@ -367,13 +368,12 @@ is_division_by_square (gimple *use_stmt, tree def)
 {
   if (gimple_code (use_stmt) == GIMPLE_ASSIGN
       && gimple_assign_rhs_code (use_stmt) == RDIV_EXPR
-      && gimple_assign_rhs1 (use_stmt) != gimple_assign_rhs2 (use_stmt))
+      && gimple_assign_rhs1 (use_stmt) != gimple_assign_rhs2 (use_stmt)
+      && !stmt_can_throw_internal (cfun, use_stmt))
     {
       tree denominator = gimple_assign_rhs2 (use_stmt);
       if (TREE_CODE (denominator) == SSA_NAME)
-	{
-	  return is_square_of (SSA_NAME_DEF_STMT (denominator), def);
-	}
+	return is_square_of (SSA_NAME_DEF_STMT (denominator), def);
     }
   return 0;
 }