From 899725b6bdc5cf16d1121c72a1e8d8dc84cfe6aa Mon Sep 17 00:00:00 2001
From: Alexey Andreev <Alexey.Andreev@jetbrains.com>
Date: Fri, 4 May 2018 19:05:11 +0300
Subject: [PATCH] C backend: fix bug in type inference, fix code generation for
 small int and long values

---
 .../backend/c/generate/CodeGeneratorUtil.java | 32 ++++++++++++-------
 .../org/teavm/model/util/TypeInferer.java     |  8 ++---
 2 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/core/src/main/java/org/teavm/backend/c/generate/CodeGeneratorUtil.java b/core/src/main/java/org/teavm/backend/c/generate/CodeGeneratorUtil.java
index 8054c70a2..95f1f945f 100644
--- a/core/src/main/java/org/teavm/backend/c/generate/CodeGeneratorUtil.java
+++ b/core/src/main/java/org/teavm/backend/c/generate/CodeGeneratorUtil.java
@@ -30,22 +30,30 @@ public final class CodeGeneratorUtil {
         } else if (value instanceof Integer) {
             int i = (Integer) value;
             long v = i;
-            if (i < 0) {
-                writer.print("-");
-                v = -i;
+            if (i == Integer.MIN_VALUE) {
+                writer.print("(int32_t) INT32_C(0x80000000)");
+            } else {
+                if (i < 0) {
+                    writer.print("-");
+                    v = -v;
+                }
+                writer.print("INT32_C(");
+                writeLongConstant(writer, v);
+                writer.print(")");
             }
-            writer.print("INT32_C(");
-            writeLongConstant(writer, v);
-            writer.print(")");
         } else if (value instanceof Long) {
             long v = (Long) value;
-            if (v < 0) {
-                writer.print("-");
-                v = -v;
+            if (v == Long.MIN_VALUE) {
+                writer.print("(int64_t) INT64_C(0x8000000000000000)");
+            } else {
+                if (v < 0) {
+                    writer.print("-");
+                    v = -v;
+                }
+                writer.print("INT64_C(");
+                writeLongConstant(writer, v);
+                writer.print(")");
             }
-            writer.print("INT64_C(");
-            writeLongConstant(writer, v);
-            writer.print(")");
         } else if (value instanceof Float) {
             float f = (Float) value;
             if (Float.isInfinite(f)) {
diff --git a/core/src/main/java/org/teavm/model/util/TypeInferer.java b/core/src/main/java/org/teavm/model/util/TypeInferer.java
index afe8ba713..60b7bb2a6 100644
--- a/core/src/main/java/org/teavm/model/util/TypeInferer.java
+++ b/core/src/main/java/org/teavm/model/util/TypeInferer.java
@@ -90,7 +90,8 @@ public class TypeInferer {
     }
 
     public VariableType typeOf(int variableIndex) {
-        return types[variableIndex];
+        VariableType result = types[variableIndex];
+        return result != null ? result : VariableType.OBJECT;
     }
 
     VariableType convert(ValueType type) {
@@ -183,11 +184,6 @@ public class TypeInferer {
             types[receiver.getIndex()] = VariableType.OBJECT;
         }
 
-        @Override
-        public void nullConstant(VariableReader receiver) {
-            types[receiver.getIndex()] = VariableType.OBJECT;
-        }
-
         @Override
         public void nullCheck(VariableReader receiver, VariableReader value) {
             builder.addEdge(value.getIndex(), receiver.getIndex());