From 5d55c8c863ea9909064ee847f25163bf02e5e8f2 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Hannu=20Niemist=C3=B6?= <hannu.niemisto@semantum.fi>
Date: Fri, 12 May 2017 13:22:50 +0300
Subject: [PATCH] (refs #7218) Sort labels by integer values when generating
 switch

Change-Id: Ic6acb6241151f3d178e4c5bdf9c4fac5424b6100
---
 .../internal/codegen/ssa/exits/Switch.java         | 14 +++++++++++---
 .../scl/compiler/tests/ModuleRegressionTests.java  |  1 +
 .../simantics/scl/compiler/tests/scl/Matching6.scl |  9 +++++++++
 3 files changed, 21 insertions(+), 3 deletions(-)
 create mode 100644 tests/org.simantics.scl.compiler.tests/src/org/simantics/scl/compiler/tests/scl/Matching6.scl

diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/codegen/ssa/exits/Switch.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/codegen/ssa/exits/Switch.java
index 27f853e02..386199d83 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/codegen/ssa/exits/Switch.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/codegen/ssa/exits/Switch.java
@@ -1,6 +1,7 @@
 package org.simantics.scl.compiler.internal.codegen.ssa.exits;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 
 import org.objectweb.asm.Label;
 import org.simantics.scl.compiler.common.exceptions.InternalCompilerError;
@@ -26,6 +27,8 @@ import org.simantics.scl.compiler.types.TVar;
 import org.simantics.scl.compiler.types.Type;
 import org.simantics.scl.compiler.types.Types;
 
+import gnu.trove.map.hash.TIntObjectHashMap;
+
 public class Switch extends SSAExit implements ValRefBinder {
 
     ValRef scrutinee;
@@ -60,14 +63,19 @@ public class Switch extends SSAExit implements ValRefBinder {
         int defaultId;
         for(defaultId=0;defaultId<branches.length-1&&branches[defaultId].constructor!=null;++defaultId);
         int[] values = new int[defaultId];
-        Label[] labels = new Label[defaultId];
         Cont[] continuations = new Cont[defaultId+1];
+        TIntObjectHashMap<Label> labelMap = new TIntObjectHashMap<Label>(defaultId); 
         for(int i=0;i<defaultId;++i) {
-            values[i] = ((IntegerConstant)branches[i].constructor).getValue();
+            int value = ((IntegerConstant)branches[i].constructor).getValue();
+            values[i] = value;
             Cont cont = branches[i].cont.getBinding();
-            labels[i] = mb.getLabel(cont);
+            labelMap.put(value,  mb.getLabel(cont));
             continuations[i] = cont;
         }
+        Arrays.sort(values);
+        Label[] labels = new Label[defaultId];
+        for(int i=0;i<defaultId;++i)
+            labels[i] = labelMap.get(values[i]);
         Label defaultLabel;
         {
             Cont cont = branches[defaultId].cont.getBinding();
diff --git a/tests/org.simantics.scl.compiler.tests/src/org/simantics/scl/compiler/tests/ModuleRegressionTests.java b/tests/org.simantics.scl.compiler.tests/src/org/simantics/scl/compiler/tests/ModuleRegressionTests.java
index 4701e2586..dc2c77524 100644
--- a/tests/org.simantics.scl.compiler.tests/src/org/simantics/scl/compiler/tests/ModuleRegressionTests.java
+++ b/tests/org.simantics.scl.compiler.tests/src/org/simantics/scl/compiler/tests/ModuleRegressionTests.java
@@ -147,6 +147,7 @@ public class ModuleRegressionTests extends TestBase {
     @Test public void Matching2() { test(); }
     @Test public void Matching4() { test(); }
     @Test public void Matching5() { test(); }
+    @Test public void Matching6() { test(); }
     @Test public void MatchingWithMissingParameter() { test(); }
     @Test public void MatchingWithoutTypeAnnotations() { test(); }
     @Test public void MaximumBy() { test(); }
diff --git a/tests/org.simantics.scl.compiler.tests/src/org/simantics/scl/compiler/tests/scl/Matching6.scl b/tests/org.simantics.scl.compiler.tests/src/org/simantics/scl/compiler/tests/scl/Matching6.scl
new file mode 100644
index 000000000..f4f7cc430
--- /dev/null
+++ b/tests/org.simantics.scl.compiler.tests/src/org/simantics/scl/compiler/tests/scl/Matching6.scl
@@ -0,0 +1,9 @@
+import "Prelude"
+
+main = do 
+    match 1+1 :: Integer with
+        2 -> 2
+        0 -> 0
+        1 -> 1
+--
+2
\ No newline at end of file
-- 
2.43.2