diff --git a/src/main/scala/apps/mm.scala b/src/main/scala/apps/mm.scala
index 1813aff81..52de9846b 100644
--- a/src/main/scala/apps/mm.scala
+++ b/src/main/scala/apps/mm.scala
@@ -107,8 +107,8 @@ object mm {
             mapWorkGroup(0)(fun(p3 =>
               zip(p2)(p3) |> // O'.(v8.v5.f x v8.v7.f)
                 // FIXME: there seems to be a bug in AdjustArraySizesForAllocations
-//                oclReduceSeq(AddressSpace.Private)(fun((p13, p14) =>
-                  oclReduceSeq(AddressSpace.Local)(fun((p13, p14) =>
+                oclReduceSeq(AddressSpace.Private)(fun((p13, p14) =>
+//                  oclReduceSeq(AddressSpace.Local)(fun((p13, p14) =>
                   // (v5/^v4).(v7/^v3).v4.v3.f x (v8.v5.f x v8.v7.f)
                   let (toLocal(makePair(
                     p14._1 |> join |> split(v6) |> // ((v8 x v5) /^ v6).v6.f
diff --git a/src/main/scala/rise/autotune/execution.scala b/src/main/scala/rise/autotune/execution.scala
index 841ae26bc..616349ace 100644
--- a/src/main/scala/rise/autotune/execution.scala
+++ b/src/main/scala/rise/autotune/execution.scala
@@ -43,11 +43,11 @@ object execution {
 
     val codegenStart = System.currentTimeMillis()
 
-    val codegenResult = try {
+    val codegenResult = /* try */ {
 
       // run code-generation with timeout
-      val codgenResult = autoTuningUtils.runWithTimeout(
-        timeouts.codegenerationTimeout)(gen.opencl.hosted("fun").fromExpr(expression))
+      val codgenResult: Option[gen.opencl.HostedModule] = /*autoTuningUtils.runWithTimeout(
+        timeouts.codegenerationTimeout)(*/Some(gen.opencl.hosted("fun").fromExpr(expression))//)
 
       // check if timeout was triggered
       codgenResult match {
@@ -58,10 +58,10 @@ object execution {
           )
         )
       }
-    } catch {
+    } /* catch {
       case e:Throwable =>
         Left(AutoTuningError(CODE_GENERATION_ERROR, Some(e.getCause.getMessage)))
-    }
+    } */
 
     val codegenTime = TimeSpan.inMilliseconds((System.currentTimeMillis() - codegenStart).toDouble)
 
@@ -92,6 +92,8 @@ object execution {
 
         assert(executionIterations > 0)
 
+        println(program)
+
         // execute program
         val result = executeWithRuntime(
           program,
@@ -103,6 +105,8 @@ object execution {
           execution
         )
 
+        println(result)
+
         ExecutionResult(
           runtime = result._1,
           codegenTime = Some(codegenTime),
diff --git a/src/main/scala/shine/C/Compilation/CodeGenerator.scala b/src/main/scala/shine/C/Compilation/CodeGenerator.scala
index 2efd4a8a5..20bbdcab6 100644
--- a/src/main/scala/shine/C/Compilation/CodeGenerator.scala
+++ b/src/main/scala/shine/C/Compilation/CodeGenerator.scala
@@ -90,7 +90,8 @@ class CodeGenerator(val decls: CodeGenerator.Declarations,
     visitAndGenerateNat(phrase match {
       case Phrases.IfThenElse(cond, thenP, elseP) =>
         cond |> exp(env, Nil, cond =>
-          C.AST.IfThenElse(cond, cmd(env)(thenP), Some(cmd(env)(elseP))))
+          C.AST.IfThenElse(cond, C.AST.Block(scala.Seq(cmd(env)(thenP))),
+            Some(C.AST.Block(scala.Seq(cmd(env)(elseP))))))
 
       case i: Identifier[CommType] => env.commEnv(i)
 
diff --git a/src/main/scala/shine/DPIA/Compilation/Passes/UnrollLoops.scala b/src/main/scala/shine/DPIA/Compilation/Passes/UnrollLoops.scala
index a09680741..8efb01447 100644
--- a/src/main/scala/shine/DPIA/Compilation/Passes/UnrollLoops.scala
+++ b/src/main/scala/shine/DPIA/Compilation/Passes/UnrollLoops.scala
@@ -85,9 +85,18 @@ object UnrollLoops {
       shine.DPIA.DSL.comment(s"unrolling loop of $numIter"))({
       case (prev, i) =>
         val index = init + Cst(i * incr)
-        assert(isSmaller(index, n).contains(true)) //TODO add if-guards otherwise.
         //TODO store result of init in temporary variable
-        Seq(prev, genBody(index))
+        val current = if (isSmaller(index, n).contains(true)) {
+          genBody(index)
+        } else {
+          shine.DPIA.Phrases.IfThenElse(
+            shine.DPIA.Phrases.BinOp(shine.DPIA.Phrases.Operators.Binary.LT,
+              shine.DPIA.Phrases.Natural(index),
+              shine.DPIA.Phrases.Natural(n)),
+            genBody(index),
+            shine.DPIA.primitives.imperative.Skip())
+        }
+        Seq(prev, current)
     })
 
     tmp