Very basic string support. (#10)

String, ByteArray support, type declarations.

runtime/src/main/cpp/Memory.cpp

@@ -1,5 +1,6 @@
 #include <stdlib.h>
 
+#include "Assert.h"
 #include "Memory.h"
 
 void FreeObject(ContainerHeader* header) {
@@ -16,16 +17,28 @@ ArenaContainer::ArenaContainer(uint32_t size) {
     header->end_ = header->current_ + size;
 }
 
-void ObjectContainer::Init(const TypeInfo* type_info, uint32_t elements) {
+void ObjectContainer::Init(const TypeInfo* type_info) {
+  RuntimeAssert(type_info->instanceSize_ >= 0, "Must be an object");
   header_ = reinterpret_cast<ContainerHeader*>(
       calloc(sizeof(ContainerHeader) + sizeof(ObjHeader) +
-             type_info->size_ * elements, 1));
+             type_info->instanceSize_, 1));
   header_->ref_count_ = CONTAINER_TAG_INCREMENT;
   SetMeta(GetPlace(), type_info);
 }
 
+void ArrayContainer::Init(const TypeInfo* type_info, uint32_t elements) {
+  RuntimeAssert(type_info->instanceSize_ < 0, "Must be an array");
+  header_ = reinterpret_cast<ContainerHeader*>(
+      calloc(sizeof(ContainerHeader) + sizeof(ArrayHeader) -
+             type_info->instanceSize_ * elements, 1));
+  header_->ref_count_ = CONTAINER_TAG_INCREMENT;
+  GetPlace()->count_ = elements;
+  SetMeta(GetPlace(), type_info);
+}
+
 ObjHeader* ArenaContainer::PlaceObject(const TypeInfo* type_info) {
-  int size = type_info->size_ + sizeof(ObjHeader);
+  RuntimeAssert(type_info->instanceSize_ >= 0, "must be an object");
+  uint32_t size = type_info->instanceSize_ + sizeof(ObjHeader);
   ObjHeader* result = reinterpret_cast<ObjHeader*>(Place(size));
   if (!result) {
       return nullptr;
@@ -35,7 +48,8 @@ ObjHeader* ArenaContainer::PlaceObject(const TypeInfo* type_info) {
 }
 
 ArrayHeader* ArenaContainer::PlaceArray(const TypeInfo* type_info, int count) {
-  int size = sizeof(ArrayHeader) + type_info->size_ * count;
+  RuntimeAssert(type_info->instanceSize_ < 0, "must be an array");
+  uint32_t size = sizeof(ArrayHeader) - type_info->instanceSize_ * count;
   ArrayHeader* result = reinterpret_cast<ArrayHeader*>(Place(size));
   if (!result) {
     return nullptr;
@@ -55,11 +69,13 @@ void InitMemory() {
 
 // Now we ignore all placement hints and always allocate heap space for new object.
 void* AllocInstance(const TypeInfo* type_info, PlacementHint hint) {
+  RuntimeAssert(type_info->instanceSize_ >= 0, "must be an object");
   return ObjectContainer(type_info).GetPlace();
 }
 
 void* AllocArrayInstance(const TypeInfo* type_info, PlacementHint hint, uint32_t elements) {
-  return ObjectContainer(type_info, elements).GetPlace();
+  RuntimeAssert(type_info->instanceSize_ < 0, "must be an array");
+  return ArrayContainer(type_info, elements).GetPlace();
 }
 
 #ifdef __cplusplus

runtime/src/main/cpp/Memory.h

@@ -5,8 +5,11 @@
 #include "TypeInfo.h"
 
 typedef enum {
+  // Allocation guaranteed to be frame local.
   SCOPE_FRAME = 0,
+  // Allocation is generic global allocation.
   SCOPE_GLOBAL = 1,
+  // Allocation shall take place in current arena.
   SCOPE_ARENA = 2
 } PlacementHint;
 
@@ -22,7 +25,7 @@ typedef enum {
   CONTAINER_TAG_INVALID = 3,
   // Actual value to increment/decrement conatiner by. Tag is in lower bits.
   CONTAINER_TAG_INCREMENT = 1 << 2,
-  //
+  // Mask for container type.
   CONTAINER_TAG_MASK = (CONTAINER_TAG_INCREMENT - 1)
 } ContainerTag;
 
@@ -37,12 +40,13 @@ struct ObjHeader {
 
 // Header of value type array objects.
 struct ArrayHeader : public ObjHeader {
+  // Elements count. Element size is stored in instanceSize_ field of TypeInfo, negated.
   uint32_t count_;
 };
 
 // Header of all container objects. Contains reference counter.
 struct ContainerHeader {
-  // Reference counter of container. Maybe use some upper bit of counter for
+  // Reference counter of container. Uses two lower bits of counter for
   // container type (for polymorphism in ::Release()).
   volatile uint32_t ref_count_;
 };
@@ -55,7 +59,27 @@ struct ArenaContainerHeader : public ContainerHeader {
   uint8_t* end_;
 };
 
-// Thos two operations are implemented by translator when storing references
+inline void* AddressOfElementAt(ArrayHeader* obj, int32_t index) {
+  // Instance size is negative.
+  return reinterpret_cast<uint8_t*>(obj + 1) - obj->type_info_->instanceSize_ * index;
+}
+
+// Optimized version not accessing type info.
+inline uint8_t* ByteArrayAddressOfElementAt(ArrayHeader* obj, int32_t index) {
+  return reinterpret_cast<uint8_t*>(obj + 1) + index;
+}
+
+inline const uint8_t* ByteArrayAddressOfElementAt(const ArrayHeader* obj, int32_t index) {
+  return reinterpret_cast<const uint8_t*>(obj + 1) + index;
+}
+
+inline uint32_t ArraySizeBytes(const ArrayHeader* obj) {
+  // Instance size is negative.
+  return -obj->type_info_->instanceSize_ * obj->count_;
+}
+
+
+// Those two operations are implemented by translator when storing references
 // to objects.
 inline void AddRef(ContainerHeader* header) {
   // Looking at container type we may want to skip AddRef() totally
@@ -141,12 +165,9 @@ class Container {
 // Container for a single object.
 class ObjectContainer : public Container {
  public:
+  // Single instance.
   explicit ObjectContainer(const TypeInfo* type_info) {
-    Init(type_info, 1);
+    Init(type_info);
-  }
-
-  ObjectContainer(const TypeInfo* type_info, uint32_t elements) {
-    Init(type_info, elements);
   }
 
   // Object container shalln't have any dtor, as it's being freed by ::Release().
@@ -155,10 +176,28 @@ class ObjectContainer : public Container {
         reinterpret_cast<uint8_t*>(header_) + sizeof(ContainerHeader));
   }
 
+ private:
+  void Init(const TypeInfo* type_info);
+};
+
+
+class ArrayContainer : public Container {
+ public:
+  ArrayContainer(const TypeInfo* type_info, uint32_t elements) {
+    Init(type_info, elements);
+  }
+
+  // Array container shalln't have any dtor, as it's being freed by ::Release().
+  ArrayHeader* GetPlace() const {
+    return reinterpret_cast<ArrayHeader*>(
+        reinterpret_cast<uint8_t*>(header_) + sizeof(ContainerHeader));
+  }
+
  private:
   void Init(const TypeInfo* type_info, uint32_t elements);
 };
 
+
 // Class representing arena-style placement container.
 // Container is used for reference counting,
 // and it is assumed that objects with related placement will share container. Only

runtime/src/main/cpp/Natives.cpp

@@ -0,0 +1,46 @@
+#include <string.h>
+
+#include "Assert.h"
+#include "Exceptions.h"
+#include "Memory.h"
+#include "Natives.h"
+#include "Types.h"
+
+extern "C" {
+
+// TODO: those must be compiler intrinsics afterwards.
+KByte Kotlin_ByteArray_get(const ArrayHeader* obj, int32_t index) {
+  if (static_cast<uint32_t>(index) >= obj->count_) {
+    ThrowArrayIndexOutOfBoundsException();
+  }
+  return *ByteArrayAddressOfElementAt(obj, index);
+}
+
+void Kotlin_ByteArray_set(ArrayHeader* obj, int32_t index, KByte value) {
+  if (static_cast<uint32_t>(index) >= obj->count_) {
+    ThrowArrayIndexOutOfBoundsException();
+  }
+  *ByteArrayAddressOfElementAt(obj, index) = value;
+}
+
+KChar Kotlin_String_get(const ArrayHeader* obj, int32_t index) {
+  // TODO: support full UTF-8.
+  if (static_cast<uint32_t>(index) >= obj->count_) {
+    ThrowArrayIndexOutOfBoundsException();
+  }
+  return *ByteArrayAddressOfElementAt(obj, index);
+}
+
+ArrayHeader* Kotlin_String_fromUtf8Array(const ArrayHeader* array) {
+  RuntimeAssert(array->type_info_ == theByteArrayTypeInfo, "Must get a byte array");
+  uint32_t length = ArraySizeBytes(array);
+  // TODO: support full UTF-8.
+  ArrayHeader* result = ArrayContainer(theStringTypeInfo, length).GetPlace();
+  memcpy(
+      ByteArrayAddressOfElementAt(result, 0),
+      ByteArrayAddressOfElementAt(array, 0),
+      length);
+  return result;
+}
+
+}

runtime/src/main/cpp/Natives.h

@@ -0,0 +1,24 @@
+#ifndef RUNTIME_NATIVES_H
+#define RUNTIME_NATIVES_H
+
+#include "Memory.h"
+#include "Types.h"
+
+typedef uint16_t KChar;
+typedef uint8_t KByte;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// TODO: those must be compiler intrinsics afterwards.
+KByte Kotlin_ByteArray_get(const ArrayHeader* obj, int32_t index);
+void Kotlin_ByteArray_set(ArrayHeader* obj, int32_t index, KByte value);
+KChar Kotlin_String_get(const ArrayHeader* obj, int32_t index);
+ArrayHeader* Kotlin_String_fromUtf8Array(const ArrayHeader* array);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // RUNTIME_NATIVES_H

runtime/src/main/cpp/TypeInfo.h

@@ -6,6 +6,8 @@
 #include "Names.h"
 
 // An element of sorted by hash in-place array representing methods.
+// For systems where introspection is not needed - only open methods are in
+// this table.
 struct MethodTableRecord {
     MethodNameHash nameSignature_;
     void* methodEntryPoint_;
@@ -17,11 +19,13 @@ struct FieldTableRecord {
     int fieldOffset_;
 };
 
-// This struct represents runtime type information and by itself is compile time
+// This struct represents runtime type information and by itself is the compile time
 // constant.
 struct TypeInfo {
     ClassNameHash name_;
-    int size_;
+    // Negative value marks array class/string, and it is negated element size.
+    int32_t instanceSize_;
+    // Must be pointer to Any for array classes, and null for Any.
     const TypeInfo* superType_;
     const int* objOffsets_;
     int objOffsetsCount_;
@@ -29,9 +33,9 @@ struct TypeInfo {
     int implementedInterfacesCount_;
     void* const* vtable_; // TODO: place vtable at the end of TypeInfo to eliminate the indirection
     const MethodTableRecord* openMethods_;
-    int openMethodsCount_;
+    uint32_t openMethodsCount_;
     const FieldTableRecord* fields_;
-    int fieldsCount_;
+    uint32_t fieldsCount_;
 };
 
 #ifdef __cplusplus

runtime/src/main/cpp/Types.cpp

@@ -0,0 +1,69 @@
+#include "Types.h"
+
+namespace {
+// Use 'echo -n "kotlin.ByteArray" | shasum -| xargs ~/bin/as_array' to generate hash.
+
+const TypeInfo implAnyTypeInfo = {
+  // kotlin.Any
+  { 0x6a, 0x97, 0xc2, 0x61, 0x64, 0x3a, 0xc6, 0x5e, 0x2a, 0x03,
+    0xf9, 0xc1, 0x4c, 0x1f, 0x66, 0x9a, 0x44, 0xb2, 0x6b, 0x11 },
+  0,       // instanceSize_
+  nullptr, // superType_
+  nullptr, // objOffsets
+  0,       // objOffsetsCount_
+  nullptr, // implementedInterfaces_
+  0,       // implementedInterfacesCount_
+  nullptr, // vtable_
+  nullptr, // openMethods_
+  0,       // openMethodsCount_
+  nullptr, // fields_
+  0        // fieldsCount_
+};
+
+const TypeInfo implByteArrayTypeInfo = {
+  // kotlin.ByteArray
+  { 0x9e, 0x23, 0xa6, 0xa6, 0x91, 0x9b, 0x6b, 0x0a, 0x00, 0xc5,
+    0x35, 0xe8, 0xd9, 0xd1, 0xa3, 0xb6, 0xc5, 0xc6, 0xd7, 0x65 },
+  -1,               // instanceSize_, array of 1 byte elements
+  &implAnyTypeInfo, // superType_
+  nullptr,          // objOffsets
+  0,                // objOffsetsCount_
+  // TODO: actually, shall implement cloneable, it seems.
+  nullptr,          // implementedInterfaces_
+  0,                // implementedInterfacesCount_
+  nullptr,          // vtable_
+  nullptr,          // openMethods_
+  0,                // openMethodsCount_
+  nullptr,          // fields_
+  0                 // fieldsCount_
+};
+
+const TypeInfo implStringTypeInfo = {
+  { 0x5b, 0xac, 0x68, 0xed, 0x43, 0xd4, 0x81, 0x4a, 0x14, 0x18,
+    0x10, 0xfa, 0x65, 0x09, 0xb9, 0xef, 0x20, 0x0a, 0xba, 0x78 }, // kotlin.String
+  -1,               // instanceSize_, Strings are treated as array of 1 byte elements
+  &implAnyTypeInfo, // superType_
+  nullptr,          // objOffsets
+  0,                // objOffsetsCount_
+  nullptr,          // implementedInterfaces_
+  0,                // implementedInterfacesCount_
+  nullptr,          // vtable_
+  nullptr,          // openMethods_
+  0,                // openMethodsCount_
+  nullptr,          // fields_
+  0                 // fieldsCount_
+};
+
+}  // namespace
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+const TypeInfo* theAnyTypeInfo = &implAnyTypeInfo;
+const TypeInfo* theByteArrayTypeInfo = &implByteArrayTypeInfo;
+const TypeInfo* theStringTypeInfo = &implStringTypeInfo;
+
+#ifdef __cplusplus
+}
+#endif

runtime/src/main/cpp/Types.h

@@ -0,0 +1,18 @@
+#ifndef RUNTIME_TYPES_H
+#define RUNTIME_TYPES_H
+
+#include "TypeInfo.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern const TypeInfo* theAnyTypeInfo;
+extern const TypeInfo* theByteArrayTypeInfo;
+extern const TypeInfo* theStringTypeInfo;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // RUNTIME_TYPES_H

runtime/src/main/kotlin/kotlin_native/String.kt

@@ -0,0 +1,28 @@
+package kotlin_native
+
+class ByteArray(size: Int) {
+    public val size: Int
+
+    external public operator fun get(index: Int): Byte
+
+    external public operator fun set(index: Int, value: Byte): Unit
+}
+
+class String {
+    companion object {
+        external fun fromUtf8Array(ByteArray: array) : String
+    }
+    external public operator fun plus(other: Any?): String
+
+    public val length: Int
+        get() = getStringLength()
+
+    // Can be O(N).
+    external public fun get(index: Int): Char
+
+    // external public fun subSequence(startIndex: Int, endIndex: Int): CharSequence
+
+    external public fun compareTo(other: String): Int
+
+    external private fun getStringLength(): Int
+}