Keep tuple vararg loop bindings rooted through lowering (#1269)

* Keep lowered vararg tuple locals rooted

* Run compiler fuzz tests in the SmallCheck JUnit suite

* Fix compiler fuzz suite execution

Author: Frotty

de.peeeq.wurstscript/parserspec/jass_im.parseq

@@ -74,6 +74,9 @@ ImMethod(@ignoreForEquality de.peeeq.wurstscript.ast.Element trace,
 
 
 ImStmts * ImStmt
+ImVarargLoopVars * ImVarargLoopVar
+
+ImVarargLoopVar(ref ImVar var)
 
 ImStmt = 
 	  ImIf(@ignoreForEquality de.peeeq.wurstscript.ast.Element trace, ImExpr condition, ImStmts thenBlock, ImStmts elseBlock)
@@ -82,7 +85,7 @@ ImStmt =
 	| ImReturn(@ignoreForEquality de.peeeq.wurstscript.ast.Element trace, ImExprOpt returnValue)
 	| ImSet(@ignoreForEquality de.peeeq.wurstscript.ast.Element trace, ImLExpr left, ImExpr right)
 	| ImExpr
-	| ImVarargLoop(@ignoreForEquality de.peeeq.wurstscript.ast.Element trace, ImStmts body, ref ImVar loopVar)
+	| ImVarargLoop(@ignoreForEquality de.peeeq.wurstscript.ast.Element trace, ImStmts body, ImVarargLoopVars loopVars)
 
 
 ImExprOpt =

de.peeeq.wurstscript/src/main/java/de/peeeq/wurstscript/intermediatelang/interpreter/RunStatement.java

@@ -1,5 +1,6 @@
 package de.peeeq.wurstscript.intermediatelang.interpreter;
 
+import com.google.common.base.Preconditions;
 import de.peeeq.wurstio.jassinterpreter.InterpreterException;
 import de.peeeq.wurstio.jassinterpreter.VarargArray;
 import de.peeeq.wurstscript.intermediatelang.ILaddress;
@@ -72,11 +73,13 @@ public static void run(ImStmts stmts, ProgramState globalState, LocalState local
 
 
     public static void run(ImVarargLoop loop, ProgramState globalState, LocalState localState) {
+        Preconditions.checkState(loop.getLoopVars().size() == 1,
+            "Expected one vararg loop variable in the interpreter.");
         ImFunction func = loop.getNearestFunc();
         ImVar varargParam = func.getParameters().get(func.getParameters().size() - 1);
         VarargArray val = (VarargArray) localState.getVal(varargParam);
         for (int i = 0; i < val.size(); i++) {
-            localState.setVal(loop.getLoopVar(), val.get(i));
+            localState.setVal(loop.getLoopVars().get(0).getVar(), val.get(i));
             loop.getBody().runStatements(globalState, localState);
         }
     }

de.peeeq.wurstscript/src/main/java/de/peeeq/wurstscript/intermediatelang/optimizer/LocalMerger.java

@@ -110,8 +110,10 @@ private static void applyMerges(ImFunction func, Map<ImVar, ImVar> merges) {
             }
             @Override public void visit(ImVarargLoop varargLoop) {
                 super.visit(varargLoop);
-                ImVar m = merges.get(varargLoop.getLoopVar());
-                if (m != null) varargLoop.setLoopVar(m);
+                for (ImVarargLoopVar loopVar : varargLoop.getLoopVars()) {
+                    ImVar m = merges.get(loopVar.getVar());
+                    if (m != null) loopVar.setVar(m);
+                }
             }
         });
     }
@@ -123,6 +125,10 @@ private static int removeUnusedLocals(ImFunction f) {
             @Override public void visit(ImVarAccess va) { super.visit(va); used.add(va.getVar()); }
             @Override public void visit(ImMemberAccess ma) { super.visit(ma); used.add(ma.getVar()); }
             @Override public void visit(ImVarArrayAccess vaa) { super.visit(vaa); used.add(vaa.getVar()); }
+            @Override public void visit(ImVarargLoop loop) {
+                super.visit(loop);
+                loop.getLoopVars().forEach(v -> used.add(v.getVar()));
+            }
         });
         List<ImVar> locals = new ArrayList<>(f.getLocals());
         int before = locals.size();

de.peeeq.wurstscript/src/main/java/de/peeeq/wurstscript/intermediatelang/optimizer/LocalPlayerContextAnalyzer.java

@@ -261,9 +261,9 @@ private void indexElementAfterChildren(Element element, ImFunction owner, Object
         } else if (element instanceof ImVarargLoop) {
             ImVar varargParameter = varargParameter(owner);
             if (varargParameter != null) {
-                addDependency(
-                    variableFact(varargParameter),
-                    variableFact(((ImVarargLoop) element).getLoopVar()));
+                for (ImVarargLoopVar loopVar : ((ImVarargLoop) element).getLoopVars()) {
+                    addDependency(variableFact(varargParameter), variableFact(loopVar.getVar()));
+                }
             }
         }
 

de.peeeq.wurstscript/src/main/java/de/peeeq/wurstscript/intermediatelang/optimizer/SideEffectAnalyzer.java

@@ -316,7 +316,7 @@ public void visit(ImSet va) {
             @Override
             public void visit(ImVarargLoop va) {
                 super.visit(va);
-                imVars.add(va.getLoopVar());
+                va.getLoopVars().forEach(v -> imVars.add(v.getVar()));
             }
 
         });
@@ -405,7 +405,7 @@ public void visit(ImSet va) {
             @Override
             public void visit(ImVarargLoop va) {
                 super.visit(va);
-                imVars.add(va.getLoopVar());
+                va.getLoopVars().forEach(v -> imVars.add(v.getVar()));
             }
 
         });

de.peeeq.wurstscript/src/main/java/de/peeeq/wurstscript/translation/imoptimizer/ImInliner.java

@@ -10,6 +10,7 @@
 import de.peeeq.wurstscript.types.TypesHelper;
 
 import java.util.*;
+import java.util.stream.Collectors;
 
 import static de.peeeq.wurstscript.jassIm.JassIm.ImStatementExpr;
 import static de.peeeq.wurstscript.jassIm.JassIm.ImStmts;
@@ -278,7 +279,10 @@ private ImStmts rewriteStmtForEarlyReturn(ImStmt s, ImVar doneVar, ImVar retVar)
             ImStmts loopBody = JassIm.ImStmts();
             loopBody.add(JassIm.ImExitwhen(l.getTrace(), JassIm.ImVarAccess(doneVar)));
             loopBody.addAll(rewriteForEarlyReturns(l.getBody().copy(), doneVar, retVar).removeAll());
-            return JassIm.ImStmts(JassIm.ImVarargLoop(l.getTrace(), loopBody, l.getLoopVar()));
+            return JassIm.ImStmts(JassIm.ImVarargLoop(l.getTrace(), loopBody,
+                JassIm.ImVarargLoopVars(l.getLoopVars().stream()
+                    .map(v -> JassIm.ImVarargLoopVar(v.getVar()))
+                    .collect(Collectors.toList()))));
         }
         // Keep tree ownership valid when rewrapping statements into new blocks.
         return JassIm.ImStmts(s.copy());

de.peeeq.wurstscript/src/main/java/de/peeeq/wurstscript/translation/imtranslation/AssertProperty.java

@@ -43,7 +43,9 @@ public void check(Element e) {
                     checkType(e, ((ImMethod) e).getMethodClass());
                     checkRooted(e, ((ImMethod) e).getImplementation());
                 } else if (e instanceof ImVarargLoop) {
-                    checkRooted(e, ((ImVarargLoop) e).getLoopVar());
+                    for (ImVarargLoopVar loopVar : ((ImVarargLoop) e).getLoopVars()) {
+                        checkRooted(e, loopVar.getVar());
+                    }
                 } else if (e instanceof ImTypeVarDispatch) {
                     checkRooted(e, ((ImTypeVarDispatch) e).getTypeClassFunc());
                     checkRooted(e, ((ImTypeVarDispatch) e).getTypeVariable());

de.peeeq.wurstscript/src/main/java/de/peeeq/wurstscript/translation/imtranslation/EliminateTuples.java

@@ -427,6 +427,20 @@ public void visit(ImVarAccess va) {
                 }
             }
 
+            @Override
+            public void visit(ImVarargLoop loop) {
+                super.visit(loop);
+                Preconditions.checkState(loop.getLoopVars().size() == 1,
+                    "Expected one vararg loop variable before tuple elimination.");
+                ImVar loopVar = loop.getLoopVars().get(0).getVar();
+                if (TypesHelper.typeContainsTuples(loopVar.getType())) {
+                    loop.setLoopVars(JassIm.ImVarargLoopVars(
+                        translator.getTupleScalarVars(loopVar).stream()
+                            .map(JassIm::ImVarargLoopVar)
+                            .collect(Collectors.toList())));
+                }
+            }
+
             @Override
             public void visit(ImVarArrayAccess va) {
                 super.visit(va);

de.peeeq.wurstscript/src/main/java/de/peeeq/wurstscript/translation/imtranslation/Flatten.java

@@ -10,6 +10,7 @@
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.stream.Collectors;
 
 import static de.peeeq.wurstscript.jassIm.JassIm.*;
 
@@ -659,7 +660,14 @@ public static Result flatten(ImGetStackTrace e, ImTranslator translator,
 
     public static Result flatten(ImVarargLoop s, ImTranslator translator, ImFunction f) {
         return new Result(Collections.singletonList(
-            JassIm.ImVarargLoop(s.getTrace(), flattenStatements(s.getBody(), translator, f), s.getLoopVar())));
+            JassIm.ImVarargLoop(s.getTrace(), flattenStatements(s.getBody(), translator, f),
+                copyVarargLoopVars(s.getLoopVars()))));
+    }
+
+    private static ImVarargLoopVars copyVarargLoopVars(ImVarargLoopVars loopVars) {
+        return JassIm.ImVarargLoopVars(loopVars.stream()
+            .map(v -> JassIm.ImVarargLoopVar(v.getVar()))
+            .collect(Collectors.toList()));
     }
 
 

de.peeeq.wurstscript/src/main/java/de/peeeq/wurstscript/translation/imtranslation/ImPrinter.java

@@ -507,7 +507,9 @@ public static void print(ImCompiletimeExpr e, Appendable sb, int indent) {
 
     public static void print(ImVarargLoop e, Appendable sb, int indent) {
         append(sb, "foreach vararg ");
-        e.getLoopVar().print(sb, indent);
+        append(sb, e.getLoopVars().stream()
+            .map(v -> v.getVar().getName())
+            .collect(Collectors.joining(", ")));
         append(sb, " {\n");
         e.getBody().print(sb, indent + 1);
         indent(sb, indent);
@@ -599,6 +601,10 @@ public static String asString(ImTypeArgument s) {
         return s.getType() + "" + s.getTypeClassBinding();
     }
 
+    public static String asString(ImVarargLoopVar s) {
+        return s.getVar().getName() + smallHash(s.getVar());
+    }
+
     public static void print(ImCast e, Appendable sb, int indent) {
         append(sb, "(");
         e.getExpr().print(sb, indent);