From fcbc95bbb48098c8a2576abee69f6217bc968586 Mon Sep 17 00:00:00 2001
From: Alexander Udalov <Alexander.Udalov@jetbrains.com>
Date: Tue, 2 Oct 2012 22:09:02 +0400
Subject: [PATCH] Generate not-null assertions after getting a field

---
 .../backend/src/org/jetbrains/jet/codegen/AsmUtil.java |  8 ++++++++
 .../src/org/jetbrains/jet/codegen/StackValue.java      |  1 +
 compiler/testData/codegen/notNullAssertions/A.java     |  7 +++++++
 .../codegen/notNullAssertions/AssertionChecker.kt      |  6 ++++++
 runtime/src/jet/runtime/Intrinsics.java                | 10 +++++++++-
 5 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java b/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java
index 434604b0436..dbcc8385065 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java
@@ -420,6 +420,14 @@ public class AsmUtil {
         genMethodThrow(mv, STUB_EXCEPTION, STUB_EXCEPTION_MESSAGE);
     }
 
+    public static void genNotNullAssertionForField(
+            @NotNull InstructionAdapter v,
+            @NotNull GenerationState state,
+            @NotNull PropertyDescriptor descriptor
+    ) {
+        genNotNullAssertion(v, state, descriptor, "checkFieldIsNotNull");
+    }
+
     public static void genNotNullAssertionForMethod(
             @NotNull InstructionAdapter v,
             @NotNull GenerationState state,
diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/StackValue.java b/compiler/backend/src/org/jetbrains/jet/codegen/StackValue.java
index 96866387fcc..bf715df48e8 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/StackValue.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/StackValue.java
@@ -982,6 +982,7 @@ public abstract class StackValue {
                 if (getter == null) {
                     v.visitFieldInsn(isStatic ? GETSTATIC : GETFIELD, methodOwner.getInternalName(), descriptor.getName().getName(),
                                      this.type.getDescriptor());
+                    genNotNullAssertionForField(v, state, descriptor);
                 }
                 else {
                     v.visitMethodInsn(invokeOpcode, methodOwner.getInternalName(), getter.getName(), getter.getDescriptor());
diff --git a/compiler/testData/codegen/notNullAssertions/A.java b/compiler/testData/codegen/notNullAssertions/A.java
index 4d21176cfac..8e9bd8ae717 100644
--- a/compiler/testData/codegen/notNullAssertions/A.java
+++ b/compiler/testData/codegen/notNullAssertions/A.java
@@ -1,6 +1,13 @@
 import jet.runtime.typeinfo.KotlinSignature;
+import org.jetbrains.annotations.NotNull;
 
 public class A {
+    @NotNull
+    public final String NULL = null;
+    
+    @NotNull
+    public static final String STATIC_NULL = null;
+    
     @KotlinSignature("fun foo() : String")
     public String foo() {
         return null;
diff --git a/compiler/testData/codegen/notNullAssertions/AssertionChecker.kt b/compiler/testData/codegen/notNullAssertions/AssertionChecker.kt
index 2cb57cc50f3..0df80e8bc42 100644
--- a/compiler/testData/codegen/notNullAssertions/AssertionChecker.kt
+++ b/compiler/testData/codegen/notNullAssertions/AssertionChecker.kt
@@ -49,4 +49,10 @@ fun checkAssertions(val illegalStateExpected: Boolean) {
     
     // prefix expression
     check("inc") { var a = A(); ++a }
+    
+    // field
+    check("NULL") { val a = A().NULL }
+    
+    // static field
+    check("STATIC_NULL") { val a = A.STATIC_NULL }
 }
diff --git a/runtime/src/jet/runtime/Intrinsics.java b/runtime/src/jet/runtime/Intrinsics.java
index 8db661d85ef..9478d053d0e 100644
--- a/runtime/src/jet/runtime/Intrinsics.java
+++ b/runtime/src/jet/runtime/Intrinsics.java
@@ -43,6 +43,14 @@ public class Intrinsics {
         }
     }
 
+    public static void checkFieldIsNotNull(Object value, String className, String fieldName) {
+        if (value == null) {
+            IllegalStateException exception =
+                    new IllegalStateException("Field specified as non-null contains null: " + className + "." + fieldName);
+            throw sanitizeStackTrace(exception);
+        }
+    }
+
     public static <T> Class<T> getJavaClass(T self) {
         return (Class<T>) self.getClass();
     }
@@ -66,7 +74,7 @@ public class Intrinsics {
     }
 
     private static final Set<String> METHOD_NAMES_TO_SKIP = new HashSet<String>(Arrays.asList(
-            "throwNpe", "checkReturnedValueIsNotNull"
+            "throwNpe", "checkReturnedValueIsNotNull", "checkFieldIsNotNull"
     ));
 
     private static <T extends Throwable> T sanitizeStackTrace(T throwable) {