2006-06-02 Frank Ch. Eigler <fche@elastic.org>

	PR 2645 cont'd.
	* elaborate.cxx (find_and_build): Support optional wildcards too.
	(derive_probes): Change last argument to indicate optionalness of
	parent probe point (alias reference).
	(alias_expansion_builder): Shrink epilogue-mode alias body copying.
	Pass along alias reference optionality.
	* elaborate.h: Corresponding changes.
	* testsuite/semko/thirtyfive.stp, semok/twentytwo.stp: New tests.

5 files changed, 54 insertions, 32 deletions

diff --git a/ChangeLog b/ChangeLog
index 9bbb705a..37dae951 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2006-06-02  Frank Ch. Eigler  <fche@elastic.org>
+
+	PR 2645 cont'd.
+	* elaborate.cxx (find_and_build): Support optional wildcards too.
+	(derive_probes): Change last argument to indicate optionalness of
+	parent probe point (alias reference).
+	(alias_expansion_builder): Shrink epilogue-mode alias body copying.
+	Pass along alias reference optionality.	
+	* elaborate.h: Corresponding changes.
+	* testsuite/semko/thirtyfive.stp, semok/twentytwo.stp: New tests.
+
 2006-06-02  Josh Stone  <joshua.i.stone@intel.com>
 
 	* testsuite/buildok/process_test.stp: add signal_handle test
diff --git a/elaborate.cxx b/elaborate.cxx
index 73ac6591..e24d26ff 100644
--- a/elaborate.cxx
+++ b/elaborate.cxx
@@ -287,7 +287,7 @@ match_node::find_and_build (systemtap_session& s,
 		}
 	    }
 	}
-      if (num_results == results.size())
+      if (! loc->optional && num_results == results.size())
         {
 	  // We didn't find any wildcard matches (since the size of
 	  // the result vector didn't change).  Throw an error.
@@ -376,35 +376,28 @@ alias_expansion_builder
     // there's concatenated code here and we only want one vardecl per
     // resulting variable.
 
-    if(alias->epilogue_style == true)  {
-	    for (unsigned i = 0; i < use->body->statements.size(); ++i)
-	      {
-		statement *s = deep_copy_visitor::deep_copy(use->body->statements[i]);
-		n->body->statements.push_back(s);
-	      }
-
-	    for (unsigned i = 0; i < alias->body->statements.size(); ++i)
-	      {
-		statement *s = deep_copy_visitor::deep_copy(alias->body->statements[i]);
-		n->body->statements.push_back(s);
-	      }
-
-    }  else  {
-
-	    for (unsigned i = 0; i < alias->body->statements.size(); ++i)
-	      {
-		statement *s = deep_copy_visitor::deep_copy(alias->body->statements[i]);
-		n->body->statements.push_back(s);
-	      }
-
-	    for (unsigned i = 0; i < use->body->statements.size(); ++i)
-	      {
-		statement *s = deep_copy_visitor::deep_copy(use->body->statements[i]);
-		n->body->statements.push_back(s);
-	      }
-    }
+    if (alias->epilogue_style)
+      {
+        for (unsigned i = 0; i < use->body->statements.size(); ++i)
+          n->body->statements.push_back
+            (deep_copy_visitor::deep_copy(use->body->statements[i]));
 
-    derive_probes (sess, n, finished_results, false);
+        for (unsigned i = 0; i < alias->body->statements.size(); ++i)
+          n->body->statements.push_back
+            (deep_copy_visitor::deep_copy(alias->body->statements[i]));
+      }
+    else
+      {
+        for (unsigned i = 0; i < alias->body->statements.size(); ++i)
+          n->body->statements.push_back
+            (deep_copy_visitor::deep_copy(alias->body->statements[i]));
+        
+        for (unsigned i = 0; i < use->body->statements.size(); ++i)
+          n->body->statements.push_back
+            (deep_copy_visitor::deep_copy(use->body->statements[i]));
+      }
+    
+    derive_probes (sess, n, finished_results, location->optional);
   }
 };
 
@@ -482,7 +475,7 @@ recursion_guard
 void
 derive_probes (systemtap_session& s,
                probe *p, vector<derived_probe*>& dps,
-               bool exc_outermost)
+               bool optional)
 {
   for (unsigned i = 0; i < p->locations.size(); ++i)
     {
@@ -494,8 +487,12 @@ derive_probes (systemtap_session& s,
           s.pattern_root->find_and_build (s, p, loc, 0, dps);
           unsigned num_atend = dps.size();
           
-          if (! loc->optional && num_atbegin == num_atend) // nothing new derived!
+          if (! optional && ! loc->optional && // something required, but
+              num_atbegin == num_atend) // nothing new derived!
             throw semantic_error ("no match for probe point");
+
+          // XXX: perhaps "optional" should operate at the outside
+          // loop (probe) level.
         }
       catch (const semantic_error& e)
         {
diff --git a/elaborate.h b/elaborate.h
index 689c35af..9a10283c 100644
--- a/elaborate.h
+++ b/elaborate.h
@@ -211,7 +211,7 @@ match_node
 int semantic_pass (systemtap_session& s);
 void derive_probes (systemtap_session& s,
                     probe *p, std::vector<derived_probe*>& dps,
-                    bool exc_outermost = true);
+                    bool optional = false);
 
 // A helper we use here and in translate, for pulling symbols out of lvalue
 // expressions.
diff --git a/testsuite/semko/thirtyfive.stp b/testsuite/semko/thirtyfive.stp
new file mode 100755
index 00000000..e54898af
--- /dev/null
+++ b/testsuite/semko/thirtyfive.stp
@@ -0,0 +1,4 @@
+#! stap -p2
+
+probe foo.a = kernel.function("no_such_function")? { "alias a" }
+probe foo.* { }
diff --git a/testsuite/semok/twentytwo.stp b/testsuite/semok/twentytwo.stp
new file mode 100755
index 00000000..f8f44ffb
--- /dev/null
+++ b/testsuite/semok/twentytwo.stp
@@ -0,0 +1,10 @@
+#! stap -p2
+
+probe foo.a = kernel.function("no_such_function")?, never { "alias a" }
+probe foo.* { }
+
+probe baz.a = kernel.function("no_such_function") { "alias a" }
+probe baz.* ? { }
+
+probe bar = kernel.function("no_such_function") { "alias b" }
+probe bar ? { }