From 45d31da85cc38ea3a7adeb01372be3edb2a0bcc7 Mon Sep 17 00:00:00 2001
From: Alexey Andreev <konsoletyper@gmail.com>
Date: Wed, 27 Mar 2019 19:34:30 +0300
Subject: [PATCH] Make clinit optimization weaker in order to properly handle
 case when clinit method reads state that was set somewhere in main method

---
 .../analysis/ClassInitializerAnalysis.java     | 18 +++++++++++-------
 tests/src/test/java/org/teavm/vm/VMTest.java   | 10 ++++++++++
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/core/src/main/java/org/teavm/model/analysis/ClassInitializerAnalysis.java b/core/src/main/java/org/teavm/model/analysis/ClassInitializerAnalysis.java
index 6ad234198..83c813d31 100644
--- a/core/src/main/java/org/teavm/model/analysis/ClassInitializerAnalysis.java
+++ b/core/src/main/java/org/teavm/model/analysis/ClassInitializerAnalysis.java
@@ -210,20 +210,24 @@ public class ClassInitializerAnalysis implements ClassInitializerInfo {
         public void getField(VariableReader receiver, VariableReader instance, FieldReference field,
                 ValueType fieldType) {
             if (instance == null) {
-                analyzeInitializer(field.getClassName());
+                touchField(field);
             }
         }
 
         @Override
         public void putField(VariableReader instance, FieldReference field, VariableReader value, ValueType fieldType) {
             if (instance == null) {
-                analyzeInitializer(field.getClassName());
-                if (!methodInfo.anyFieldModified && !field.getClassName().equals(currentClass)) {
-                    if (methodInfo.classesWithModifiedFields == null) {
-                        methodInfo.classesWithModifiedFields = new HashSet<>();
-                    }
-                    methodInfo.classesWithModifiedFields.add(field.getClassName());
+                touchField(field);
+            }
+        }
+
+        private void touchField(FieldReference field) {
+            analyzeInitializer(field.getClassName());
+            if (!methodInfo.anyFieldModified && !field.getClassName().equals(currentClass)) {
+                if (methodInfo.classesWithModifiedFields == null) {
+                    methodInfo.classesWithModifiedFields = new HashSet<>();
                 }
+                methodInfo.classesWithModifiedFields.add(field.getClassName());
             }
         }
 
diff --git a/tests/src/test/java/org/teavm/vm/VMTest.java b/tests/src/test/java/org/teavm/vm/VMTest.java
index 4dfdc06fb..c3f698587 100644
--- a/tests/src/test/java/org/teavm/vm/VMTest.java
+++ b/tests/src/test/java/org/teavm/vm/VMTest.java
@@ -303,6 +303,12 @@ public class VMTest {
         assertEquals("default,A;default,B;overridden,C;", sb.toString());
     }
 
+    @Test
+    public void clinitReadsState() {
+        initCount = 23;
+        assertEquals(23, ReadingStateInClinit.state);
+    }
+
     interface WithDefaultMethod {
         default String foo() {
             return "default";
@@ -342,6 +348,10 @@ public class VMTest {
 
     static int initCount;
 
+    private static class ReadingStateInClinit {
+        public static final int state = initCount;
+    }
+
     private static class AsyncClinitClass {
         static String state = "";
         String instanceState = "";