[GR-40071] String.indexOf is no longer considered PE safe.

PullRequest: fastr/2739

Author: zapster

com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/GrepFunctions.java

@@ -1210,9 +1210,9 @@ protected Info[] getInfo(String pattern, String text, boolean ignoreCase, boolea
             if (fixed) {
                 int index;
                 if (ignoreCase) {
-                    index = toLowerCase(text).indexOf(toLowerCase(pattern));
+                    index = stringIndexOf(toLowerCase(text), toLowerCase(pattern));
                 } else {
-                    index = text.indexOf(pattern);
+                    index = stringIndexOf(text, pattern);
                 }
                 if (index != -1) {
                     result = new Info[]{new Info(index + 1, pattern.length(), null, null, null)};
@@ -1232,6 +1232,11 @@ protected Info[] getInfo(String pattern, String text, boolean ignoreCase, boolea
             return new Info[]{new Info(-1, -1, null, null, null)};
         }
 
+        @TruffleBoundary
+        private static int stringIndexOf(String text, String pattern) {
+            return text.indexOf(pattern);
+        }
+
         @TruffleBoundary
         private static boolean find(Matcher m) {
             return m.find();