From 752723020ecefcb856944186b0c5437ef34a59e7 Mon Sep 17 00:00:00 2001
From: Florian Steurer <florian.steurer95@gmail.com>
Date: Fri, 22 Apr 2016 15:45:20 +0200
Subject: [PATCH] pipe execution

---
 .../typeinference/unify/TypeUnify.java        | 88 +++++--------------
 1 file changed, 24 insertions(+), 64 deletions(-)

diff --git a/src/de/dhbwstuttgart/typeinference/unify/TypeUnify.java b/src/de/dhbwstuttgart/typeinference/unify/TypeUnify.java
index 031576d9..5d51f137 100644
--- a/src/de/dhbwstuttgart/typeinference/unify/TypeUnify.java
+++ b/src/de/dhbwstuttgart/typeinference/unify/TypeUnify.java
@@ -3,7 +3,6 @@ package de.dhbwstuttgart.typeinference.unify;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.HashSet;
 import java.util.LinkedHashSet;
 import java.util.LinkedList;
@@ -11,7 +10,6 @@ import java.util.List;
 import java.util.Map.Entry;
 import java.util.Optional;
 import java.util.Set;
-import java.util.function.Function;
 import java.util.stream.Collectors;
 
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
@@ -19,13 +17,13 @@ import de.dhbwstuttgart.typeinference.unify.interfaces.IRuleSet;
 import de.dhbwstuttgart.typeinference.unify.interfaces.ISetOperations;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IUnify;
 import de.dhbwstuttgart.typeinference.unify.model.ExtendsType;
-import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import de.dhbwstuttgart.typeinference.unify.model.PairOperator;
 import de.dhbwstuttgart.typeinference.unify.model.PlaceholderType;
 import de.dhbwstuttgart.typeinference.unify.model.SuperType;
-import de.dhbwstuttgart.typeinference.unify.model.UnifyType;
-import de.dhbwstuttgart.typeinference.unify.model.PairOperator;
 import de.dhbwstuttgart.typeinference.unify.model.TypeParams;
 import de.dhbwstuttgart.typeinference.unify.model.Unifier;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyType;
 
 
 /**
@@ -49,10 +47,6 @@ public class TypeUnify {
 	 */
 	protected IRuleSet rules = new RuleSet();
 	
-	// Scheint momentan eher zu verlangsamen, vermutlich zu viele threads,
-	// threadpool und task-queue einbauen und minimale problemgröße für neuen thread
-	protected boolean parallel = false;
-	
 	/**
 	 * Computes all principal type unifiers for a set of constraints.
 	 * @param eq The set of constraints
@@ -138,66 +132,32 @@ public class TypeUnify {
 				.collect(Collectors.toCollection(HashSet::new));
 		//System.out.println(result);
 
-		// Flatten the cartesian product
-		// TODO parallelisierung möglich (scheint sich nicht zu lohnen)
-		Set<Set<UnifyPair>> eqPrimeSetFlat = new HashSet<>();
-		for(Set<Set<UnifyPair>> setToFlatten : eqPrimeSet) {
-			Set<UnifyPair> buffer = new HashSet<>();
-			setToFlatten.stream().forEach(x -> buffer.addAll(x));
-			eqPrimeSetFlat.add(buffer);
-		}
-		
-		
-		/*
-		 * Step 5: Substitution
-		 */
-		Set<Set<UnifyPair>> restartSet = new HashSet<>();
 		Set<Set<UnifyPair>> eqPrimePrimeSet = new HashSet<>();
 		
-		
-		if(parallel) {
-	        Set<Set<UnifyPair>> restartSetSync = Collections.synchronizedSet(restartSet);
-	        Set<Set<UnifyPair>> eqPrimePrimeSetSync = Collections.synchronizedSet(eqPrimePrimeSet);
+		// Flatten the cartesian product
+		// TODO parallelisierung möglich (scheint sich nicht zu lohnen)
+		for(Set<Set<UnifyPair>> setToFlatten : eqPrimeSet) {
+			Set<UnifyPair> eqPrime = new HashSet<>();
+			setToFlatten.stream().forEach(x -> eqPrime.addAll(x));
+
+			/*
+			 * Step 5: Substitution
+			 */
+			Optional<Set<UnifyPair>> eqPrimePrime = rules.subst(eqPrime);
 			
-	        eqPrimeSetFlat.parallelStream().forEach(eqPrime -> {
-				Optional<Set<UnifyPair>> eqPrimePrime = rules.subst(eqPrime);
-				
-				if (eqPrime.equals(eq))
-					eqPrimePrimeSetSync.add(eqPrime);
-				else if(eqPrimePrime.isPresent())
-					restartSetSync.add(eqPrimePrime.get());
-				else
-					restartSetSync.add(eqPrime);
-			});
+			
+			/*
+			 * Step 6 a) Restart for pairs where subst was applied
+			 * 		  b) Build the union over everything
+			 */
+			if (eqPrime.equals(eq))
+				eqPrimePrimeSet.add(eqPrime);
+			else if(eqPrimePrime.isPresent())
+				eqPrimePrimeSet.addAll(this.unify(eqPrimePrime.get(), fc));
+			else
+				eqPrimePrimeSet.addAll(this.unify(eqPrime, fc));
 		}
-		else {
-			for(Set<UnifyPair> eqPrime : eqPrimeSetFlat) {
-				Optional<Set<UnifyPair>> eqPrimePrime = rules.subst(eqPrime);
-				
-				if (eqPrime.equals(eq))
-					eqPrimePrimeSet.add(eqPrime);
-				else if(eqPrimePrime.isPresent())
-					restartSet.add(eqPrimePrime.get());
-				else
-					restartSet.add(eqPrime);
-			}
-		}
-
-		/*
-		 * Step 6 a) Restart for pairs where subst was applied
-		 * 		  b) Build the union over everything
-		 */
-		// TODO parallelisierung möglich (lohnt sich vermutlich)
 		
-		if(parallel) {
-	        Set<Set<UnifyPair>> eqPrimePrimeSetSync = Collections.synchronizedSet(eqPrimePrimeSet);
-			restartSet.parallelStream().forEach( x -> eqPrimePrimeSetSync.addAll(unify(x, fc)));
-		} 
-		else {
-			for(Set<UnifyPair> eqss : restartSet)
-				eqPrimePrimeSet.addAll(this.unify(eqss, fc));
-		}
-
 		 /*
 		  * Step 7: Filter empty sets;
 		  */