Fix recursion detection (it was detecting cycles in the call graph that were not directed cycles).

git-svn-id: https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/tools/glslang@23761 e7fa87d3-cd2b-0410-9028-fcbf551c1848

Test/recurse1.frag

@@ -26,3 +26,23 @@ void CBT();
 void CDT();
 void CAT() { CBT(); CBT(); CBT(); }
 void CCT() { CDT(); CDT(); CBT(); }
+
+// not recursive
+
+void norA() {}
+void norB() { norA(); }
+void norC() { norA(); }
+void norD() { norA(); }
+void norE() { norB(); }
+void norF() { norB(); }
+void norG() { norE(); }
+void norH() { norE(); }
+void norI() { norE(); }
+
+// not recursive, but with a call leading into a cycle if ignoring direction
+
+void norcA() { }
+void norcB() { norcA(); }
+void norcC() { norcB(); }
+void norcD() { norcC(); norcB(); } // head of cycle
+void norcE() { norcD(); } // lead into cycle