Evaluate subscripts in actualStream/inStream (#8278)

- Evaluate the subscripts in the connector reference used as argument to
  actualStream/inStream, to ensure we can look up e.g. the matching
  stream variable for a flow correctly. We already check that the
  subscripts can be evaluated, with this change we also actually
  evaluate them as intended.

Author: perost

OMCompiler/Compiler/NFFrontEnd/NFConnectEquations.mo

@@ -723,8 +723,10 @@ protected
   Connector c;
   list<Connector> sl;
   Integer set;
+  ComponentRef cr;
 algorithm
-  c := Connector.CONNECTOR(cref, Type.UNKNOWN(), Face.INSIDE,
+  cr := ComponentRef.evaluateSubscripts(cref);
+  c := Connector.CONNECTOR(cr, Type.UNKNOWN(), Face.INSIDE,
     ConnectorType.STREAM, DAE.emptyElementSource);
 
   try
@@ -734,7 +736,7 @@ algorithm
     sl := {c};
   end try;
 
-  exp := generateInStreamExp(cref, sl, sets, setsArray, variables, ctable,
+  exp := generateInStreamExp(cr, sl, sets, setsArray, variables, ctable,
     Flags.getConfigReal(Flags.FLOW_THRESHOLD));
 end evaluateInStream;
 
@@ -851,24 +853,26 @@ protected function evaluateActualStream
   output Expression exp;
   output ComponentRef flowCref;
 protected
+  ComponentRef stream_cref;
   Integer flow_dir;
   Expression flow_exp, stream_exp, instream_exp;
   Operator op;
 algorithm
-  flowCref := associatedFlowCref(streamCref);
+  stream_cref := ComponentRef.evaluateSubscripts(streamCref);
+  flowCref := associatedFlowCref(stream_cref);
   flow_dir := evaluateFlowDirection(flowCref, variables);
 
   // Select a branch if we know the flow direction, otherwise generate the whole
   // if-equation.
   if flow_dir == 1 then
-    exp := evaluateInStream(streamCref, sets, setsArray, variables, ctable);
+    exp := evaluateInStream(stream_cref, sets, setsArray, variables, ctable);
   elseif flow_dir == -1 then
-    exp := Expression.fromCref(streamCref);
+    exp := Expression.fromCref(stream_cref);
   else
     // actualStream(stream_var) = if flow_var > 0 then inStream(stream_var) else stream_var);
     flow_exp := Expression.fromCref(flowCref);
-    stream_exp := Expression.fromCref(streamCref);
-    instream_exp := evaluateInStream(streamCref, sets, setsArray, variables, ctable);
+    stream_exp := Expression.fromCref(stream_cref);
+    instream_exp := evaluateInStream(stream_cref, sets, setsArray, variables, ctable);
     op := Operator.makeGreater(ComponentRef.nodeType(flowCref));
 
     exp := Expression.IF(

testsuite/flattening/modelica/scodeinst/ActualStreamVariability2.mo

@@ -0,0 +1,33 @@
+// name: ActualStreamVariability2
+// keywords: stream actualStream connector
+// status: correct
+// cflags: -d=newInst
+//
+
+connector C
+  Real r;
+  flow Real f;
+  stream Real s;
+end C;
+
+model ActualStreamVariability2
+  C c[2];
+  parameter Integer n = 1;
+  Real as = actualStream(c[n].s);
+end ActualStreamVariability2;
+
+// Result:
+// class ActualStreamVariability2
+//   Real c[1].r;
+//   Real c[1].f;
+//   Real c[1].s;
+//   Real c[2].r;
+//   Real c[2].f;
+//   Real c[2].s;
+//   final parameter Integer n = 1;
+//   Real as = c[1].s;
+// equation
+//   c[1].f = 0.0;
+//   c[2].f = 0.0;
+// end ActualStreamVariability2;
+// endResult

testsuite/flattening/modelica/scodeinst/Makefile

@@ -6,6 +6,7 @@ ActualStream.mo \
 ActualStreamNonCref1.mo \
 ActualStreamNoStream1.mo \
 ActualStreamVariability1.mo \
+ActualStreamVariability2.mo \
 Algorithm1.mo \
 Algorithm2.mo \
 Algorithm3.mo \