a whole lot of updates tbh

pom.xml

@@ -8,5 +8,63 @@
     <artifactId>G-Wasm</artifactId>
     <version>1.0-SNAPSHOT</version>
 
+    <build>
+        <plugins>
+
+
+            <plugin>
+                <artifactId>maven-assembly-plugin</artifactId>
+                <version>2.5</version>
+                <executions>
+                    <execution>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>single</goal>
+                        </goals>
+                    </execution>
+                </executions>
+                <configuration>
+                    <outputDirectory>${project.build.directory}/bin</outputDirectory>
+                    <archive>
+                        <manifest>
+                            <mainClass>wasm.GWasm</mainClass>
+                        </manifest>
+                    </archive>
+                    <descriptorRefs>
+                        <descriptorRef>jar-with-dependencies</descriptorRef>
+                    </descriptorRefs>
+                    <finalName>${project.artifactId}</finalName>
+                    <appendAssemblyId>false</appendAssemblyId>
+                </configuration>
+            </plugin>
+
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.8.1</version>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                </configuration>
+            </plugin>
+
+
+        </plugins>
+        <resources>
+            <resource>
+                <directory>/src/main/resources</directory>
+            </resource>
+        </resources>
+    </build>
+
+    <dependencies>
+
+        <dependency>
+            <groupId>G-Earth</groupId>
+            <artifactId>G-Earth</artifactId>
+            <version>1.2</version>
+        </dependency>
+
+    </dependencies>
 
 </project>

src/main/java/wasm/GWasm.java

@@ -0,0 +1,82 @@
+package wasm;
+
+import wasm.disassembly.InvalidOpCodeException;
+import wasm.disassembly.modules.Module;
+import wasm.disassembly.modules.indices.FuncIdx;
+import wasm.disassembly.modules.indices.TypeIdx;
+import wasm.disassembly.modules.sections.export.Export;
+import wasm.disassembly.modules.sections.export.ExportDesc;
+import wasm.disassembly.modules.sections.imprt.Import;
+import wasm.disassembly.modules.sections.imprt.ImportDesc;
+import wasm.disassembly.types.FuncType;
+import wasm.disassembly.types.ResultType;
+import wasm.disassembly.types.ValType;
+
+import java.io.*;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class GWasm {
+
+    public static void extractMethods(Module module) {
+        List<TypeIdx> typesFromImports = new ArrayList<>();
+        for (Import imp : module.getImportSection().getImports()) {
+            if (imp.getImportDescription().getImportType() == 0) {
+                typesFromImports.add((TypeIdx)imp.getImportDescription().getImportValue());
+            }
+        }
+
+        List<Export> exportList = module.getExportSection().getExports();
+        for(Export export : exportList) {
+            ExportDesc desc = export.getExportDesc();
+            if (desc.getExportType() == 0) {
+                FuncIdx funcIdx = (FuncIdx) desc.getExportValue();
+                TypeIdx typeIdx;
+                if (funcIdx.getX() < typesFromImports.size()) {
+                    typeIdx = typesFromImports.get((int)(funcIdx.getX()));
+                }
+                else {
+                    typeIdx = module.getFunctionSection().getTypeIdxVector().get((int)(funcIdx.getX()) - typesFromImports.size());
+                }
+                FuncType funcType = module.getTypeSection().getFunctionTypes().get((int)(typeIdx.getX()));
+
+                System.out.println(String.format("%s ::= %s -> %s",
+                        export.getName(),
+                        "(" + funcType.getParameterType().typeList().stream().map(Enum::name).collect(Collectors.joining(" ")) + ")",
+                        "(" + funcType.getResultType().typeList().stream().map(Enum::name).collect(Collectors.joining(" ")) + ")"
+                ));
+            }
+        }
+    }
+
+    public static void main(String[] args) throws IOException, InvalidOpCodeException {
+
+        long start = System.currentTimeMillis();
+        Module module = new Module("C:\\Users\\jonas\\Desktop\\Projects\\Jznnp\\S\\habbo2020\\rawfiles\\0.6.0_(7)\\habbo2020-global-prod.wasm.code.unityweb");
+        long end = System.currentTimeMillis();
+
+        System.out.println("Assembly time: " + (end - start));
+
+//        extractMethods(module);
+//
+//        module.getImportSection().importFunctions(Collections.singletonList(
+//                new Import(
+//                        "env",
+//                        "consoleLog",
+//                        new ImportDesc(module.getTypeSection().getTypeIdxForFuncType(new FuncType(
+//                                new ResultType(Collections.singletonList(ValType.I32)),
+//                                new ResultType(Collections.emptyList())
+//                        )))
+//                )
+//        ));
+
+        start = System.currentTimeMillis();
+        module.assembleToFile("C:\\Users\\jonas\\Desktop\\Projects\\Jznnp\\S\\habbo2020\\rawfiles\\0.6.0_(7)\\out\\habbo2020-global-prod.wasm.code.unityweb");
+        end = System.currentTimeMillis();
+
+        System.out.println("Disassembly time: " + (end - start));
+
+    }
+}

src/main/java/wasm/disassembly/conventions/Creator.java

@@ -1,12 +1,13 @@
 package wasm.disassembly.conventions;
 
 import wasm.disassembly.InvalidOpCodeException;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
 
 public interface Creator<B> {
 
-    B create(BufferedInputStream in) throws IOException, InvalidOpCodeException;
+    B create(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException;
 
 }

src/main/java/wasm/disassembly/conventions/CustomVector.java

@@ -1,6 +1,8 @@
 package wasm.disassembly.conventions;
 
 import wasm.disassembly.InvalidOpCodeException;
+import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -9,16 +11,16 @@ import java.io.OutputStream;
 import java.util.ArrayList;
 import java.util.List;
 
-public class CustomVector<B> {
+public class CustomVector<B> extends WASMOpCode {
 
     private List<B> elements;
     private Assembler<B> assembler;
 
-    public CustomVector(BufferedInputStream in, Creator<B> creator, Assembler<B> assembler) throws IOException, InvalidOpCodeException {
+    public CustomVector(BufferedInputStream in, Creator<B> creator, Assembler<B> assembler, Module module) throws IOException, InvalidOpCodeException {
         long length = WUnsignedInt.read(in, 32);
         elements = new ArrayList<>();
         for (int i = 0; i < length; i++) {
-            elements.add(creator.create(in));
+            elements.add(creator.create(in, module));
         }
         this.assembler = assembler;
     }

src/main/java/wasm/disassembly/conventions/Vector.java

@@ -2,6 +2,7 @@ package wasm.disassembly.conventions;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -14,11 +15,11 @@ public class Vector<B extends WASMOpCode> extends WASMOpCode {
 
     private List<B> elements;
 
-    public Vector(BufferedInputStream in, Creator<B> creator) throws IOException, InvalidOpCodeException {
+    public Vector(BufferedInputStream in, Creator<B> creator, Module module) throws IOException, InvalidOpCodeException {
         long length = WUnsignedInt.read(in, 32);
         elements = new ArrayList<>();
         for (int i = 0; i < length; i++) {
-            elements.add(creator.create(in));
+            elements.add(creator.create(in, module));
         }
     }
 

src/main/java/wasm/disassembly/instructions/Expression.java

@@ -2,6 +2,7 @@ package wasm.disassembly.instructions;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -13,11 +14,11 @@ public class Expression extends WASMOpCode {
 
     private List<Instr> instructions;
 
-    public Expression(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Expression(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         instructions = new ArrayList<>();
         InstrType type;
         while ((type = InstrFactory.disassembleType(in)) != InstrType.END) {
-            instructions.add(InstrFactory.disassemble(in, type));
+            instructions.add(InstrFactory.disassemble(in, type, module));
         }
     }
 

src/main/java/wasm/disassembly/instructions/Instr.java

@@ -2,6 +2,7 @@ package wasm.disassembly.instructions;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 
 import java.io.IOException;
 import java.io.OutputStream;

src/main/java/wasm/disassembly/instructions/InstrFactory.java

@@ -8,6 +8,7 @@ import wasm.disassembly.instructions.misc.SingleByteInstr;
 import wasm.disassembly.instructions.numeric.*;
 import wasm.disassembly.instructions.variable.GlobalVariableInstr;
 import wasm.disassembly.instructions.variable.LocalVariableInstr;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -70,7 +71,7 @@ public class InstrFactory {
         map.put(InstrType.IXX_TRUNC_SAT_FXX_SU, TruncSatInstr::new);
     }
 
-    public static Instr disassemble(BufferedInputStream in, InstrType instrType) throws InvalidOpCodeException, IOException {
+    public static Instr disassemble(BufferedInputStream in, InstrType instrType, Module module) throws InvalidOpCodeException, IOException {
         if (instrType == InstrType.END || instrType == InstrType.ELSE) {
             throw new InvalidOpCodeException("Instruction invalid as a standalone instruction");
         }
@@ -79,7 +80,7 @@ public class InstrFactory {
             throw new InvalidOpCodeException("Invalid instruction prefix");
         }
 
-        return map.get(instrType).get(in, instrType);
+        return map.get(instrType).get(in, instrType, module);
     }
 
 }

src/main/java/wasm/disassembly/instructions/InstrSupplier.java

@@ -1,12 +1,13 @@
 package wasm.disassembly.instructions;
 
 import wasm.disassembly.InvalidOpCodeException;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
 
 public interface InstrSupplier {
 
-    Instr get(BufferedInputStream in, InstrType type) throws IOException, InvalidOpCodeException;
+    Instr get(BufferedInputStream in, InstrType type, Module module) throws IOException, InvalidOpCodeException;
 
 }

src/main/java/wasm/disassembly/instructions/control/BlockInstr.java

@@ -4,6 +4,7 @@ import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrFactory;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -16,15 +17,15 @@ public class BlockInstr extends Instr {
     private List<Instr> blockInstructions;
     private BlockType blockType;
 
-    public BlockInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public BlockInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
 
-        blockType = new BlockType(in);
+        blockType = new BlockType(in, module);
 
         blockInstructions = new ArrayList<>();
         InstrType type;
         while ((type = InstrFactory.disassembleType(in)) != InstrType.END) {
-            blockInstructions.add(InstrFactory.disassemble(in, type));
+            blockInstructions.add(InstrFactory.disassemble(in, type, module));
         }
     }
 

src/main/java/wasm/disassembly/instructions/control/BlockType.java

@@ -2,6 +2,7 @@ package wasm.disassembly.instructions.control;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.types.ValType;
 import wasm.disassembly.values.WSignedLong;
 
@@ -13,7 +14,7 @@ public class BlockType extends WASMOpCode {
 
     private Object value;
 
-    public BlockType(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public BlockType(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         in.mark(1);
         int first = in.read();
 

src/main/java/wasm/disassembly/instructions/control/BranchInstr.java

@@ -3,6 +3,7 @@ package wasm.disassembly.instructions.control;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.LabelIdx;
 
 import java.io.BufferedInputStream;
@@ -13,9 +14,9 @@ public class BranchInstr extends Instr {
 
     private LabelIdx labelIdx;
 
-    public BranchInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public BranchInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
-        labelIdx = new LabelIdx(in);
+        labelIdx = new LabelIdx(in, module);
     }
 
     public BranchInstr(InstrType instrType, LabelIdx labelIdx) throws IOException {

src/main/java/wasm/disassembly/instructions/control/BranchTableInstr.java

@@ -1,9 +1,11 @@
 package wasm.disassembly.instructions.control;
 
 import wasm.disassembly.InvalidOpCodeException;
+import wasm.disassembly.conventions.Creator;
 import wasm.disassembly.conventions.Vector;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.LabelIdx;
 
 import java.io.BufferedInputStream;
@@ -15,10 +17,10 @@ public class BranchTableInstr extends Instr {
     private Vector<LabelIdx> table;
     private LabelIdx labelIdx;
 
-    public BranchTableInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public BranchTableInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
-        table = new Vector<>(in, LabelIdx::new);
+        table = new Vector<>(in, LabelIdx::new, module);
-        labelIdx = new LabelIdx(in);
+        labelIdx = new LabelIdx(in, module);
     }
 
     public BranchTableInstr(InstrType instrType, Vector<LabelIdx> table, LabelIdx labelIdx) throws IOException {

src/main/java/wasm/disassembly/instructions/control/CallIndirectInstr.java

@@ -3,7 +3,9 @@ package wasm.disassembly.instructions.control;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.FuncIdx;
+import wasm.disassembly.modules.indices.TypeIdx;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -11,32 +13,32 @@ import java.io.OutputStream;
 
 public class CallIndirectInstr extends Instr {
 
-    private FuncIdx funcIdx;
+    private TypeIdx typeIdx;
 
-    public CallIndirectInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public CallIndirectInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
-        funcIdx = new FuncIdx(in);
+        typeIdx = new TypeIdx(in, module);
         if (in.read() != 0x00) {
             throw new InvalidOpCodeException("Unexpected non-zero byte");
         }
     }
 
-    public CallIndirectInstr(InstrType instrType, FuncIdx funcIdx) throws IOException {
+    public CallIndirectInstr(InstrType instrType, TypeIdx typeIdx) throws IOException {
         super(instrType);
-        this.funcIdx = funcIdx;
+        this.typeIdx = typeIdx;
     }
 
     @Override
     protected void assemble2(OutputStream out) throws IOException, InvalidOpCodeException {
-        funcIdx.assemble(out);
+        typeIdx.assemble(out);
         out.write(0x00);
     }
 
-    public FuncIdx getFuncIdx() {
+    public TypeIdx getTypeIdx() {
-        return funcIdx;
+        return typeIdx;
     }
 
-    public void setFuncIdx(FuncIdx funcIdx) {
+    public void setTypeIdx(TypeIdx typeIdx) {
-        this.funcIdx = funcIdx;
+        this.typeIdx = typeIdx;
     }
 }

src/main/java/wasm/disassembly/instructions/control/CallInstr.java

@@ -3,6 +3,7 @@ package wasm.disassembly.instructions.control;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.FuncIdx;
 
 import java.io.BufferedInputStream;
@@ -13,13 +14,13 @@ public class CallInstr extends Instr {
 
     private FuncIdx funcIdx;
 
-    public CallInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public CallInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
-        funcIdx = new FuncIdx(in);
+        funcIdx = new FuncIdx(in, module);
     }
 
-    public CallInstr(InstrType instrType, FuncIdx funcIdx) throws IOException {
+    public CallInstr(FuncIdx funcIdx) throws IOException {
-        super(instrType);
+        super(InstrType.CALL);  // can only be call instr
         this.funcIdx = funcIdx;
     }
 

src/main/java/wasm/disassembly/instructions/control/IfElseInstr.java

@@ -4,6 +4,7 @@ import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrFactory;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -19,10 +20,10 @@ public class IfElseInstr extends Instr {
     private BlockType blockType;
 
 
-    public IfElseInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public IfElseInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
 
-        blockType = new BlockType(in);
+        blockType = new BlockType(in, module);
         ifInstructions = new ArrayList<>();
         elseInstructions = null;
         List<Instr> currentBlock = ifInstructions;
@@ -34,7 +35,7 @@ public class IfElseInstr extends Instr {
                 currentBlock = elseInstructions;
             }
             else {
-                currentBlock.add(InstrFactory.disassemble(in, type));
+                currentBlock.add(InstrFactory.disassemble(in, type, module));
             }
         }
     }

src/main/java/wasm/disassembly/instructions/memory/Mem0Instr.java

@@ -3,13 +3,14 @@ package wasm.disassembly.instructions.memory;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 
 public class Mem0Instr extends Instr {
-    public Mem0Instr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public Mem0Instr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
         if (in.read() != 0x00) {
             throw new InvalidOpCodeException("Unexpected non-zero byte");

src/main/java/wasm/disassembly/instructions/memory/MemArg.java

@@ -2,6 +2,7 @@ package wasm.disassembly.instructions.memory;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -13,7 +14,7 @@ public class MemArg extends WASMOpCode {
     private long align;
     private long offset;
 
-    public MemArg(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public MemArg(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         align = WUnsignedInt.read(in, 32);
         offset = WUnsignedInt.read(in, 32);
     }

src/main/java/wasm/disassembly/instructions/memory/MemInstr.java

@@ -3,6 +3,7 @@ package wasm.disassembly.instructions.memory;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -12,9 +13,9 @@ public class MemInstr extends Instr {
 
     private MemArg memArg;
 
-    public MemInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public MemInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
-        memArg = new MemArg(in);
+        memArg = new MemArg(in, module);
     }
 
     public MemInstr(InstrType instrType, MemArg memArg) throws IOException {

src/main/java/wasm/disassembly/instructions/misc/SingleByteInstr.java

@@ -2,13 +2,14 @@ package wasm.disassembly.instructions.misc;
 
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 
 public class SingleByteInstr extends Instr {
-    public SingleByteInstr(BufferedInputStream in, InstrType instrType) throws IOException {
+    public SingleByteInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException {
         super(instrType);
     }
 

src/main/java/wasm/disassembly/instructions/numeric/NumericF32ConstInstr.java

@@ -3,6 +3,7 @@ package wasm.disassembly.instructions.numeric;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WFloat;
 
 import java.io.BufferedInputStream;
@@ -13,13 +14,13 @@ public class NumericF32ConstInstr extends Instr {
 
     private float constValue;
 
-    public NumericF32ConstInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public NumericF32ConstInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
         constValue = WFloat.read(in);
     }
 
-    public NumericF32ConstInstr(InstrType instrType, float constValue) throws IOException {
+    public NumericF32ConstInstr(float constValue) throws IOException {
-        super(instrType);
+        super(InstrType.F32_CONST);
         this.constValue = constValue;
     }
 

src/main/java/wasm/disassembly/instructions/numeric/NumericF64ConstInstr.java

@@ -3,6 +3,7 @@ package wasm.disassembly.instructions.numeric;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WDouble;
 
 import java.io.BufferedInputStream;
@@ -13,13 +14,13 @@ public class NumericF64ConstInstr extends Instr {
 
     private double constValue;
 
-    public NumericF64ConstInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public NumericF64ConstInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
         constValue = WDouble.read(in);
     }
 
-    public NumericF64ConstInstr(InstrType instrType, float constValue) throws IOException {
+    public NumericF64ConstInstr(float constValue) throws IOException {
-        super(instrType);
+        super(InstrType.F64_CONST);
         this.constValue = constValue;
     }
 

src/main/java/wasm/disassembly/instructions/numeric/NumericI32ConstInstr.java

@@ -3,6 +3,7 @@ package wasm.disassembly.instructions.numeric;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WSignedInt;
 
 import java.io.BufferedInputStream;
@@ -13,13 +14,13 @@ public class NumericI32ConstInstr extends Instr {
 
     private int constValue;
 
-    public NumericI32ConstInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public NumericI32ConstInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
         constValue = WSignedInt.read(in, 32);
     }
 
-    public NumericI32ConstInstr(InstrType instrType, int constValue) throws IOException {
+    public NumericI32ConstInstr(int constValue) throws IOException {
-        super(instrType);
+        super(InstrType.I32_CONST);
         this.constValue = constValue;
     }
 

src/main/java/wasm/disassembly/instructions/numeric/NumericI64ConstInstr.java

@@ -3,6 +3,7 @@ package wasm.disassembly.instructions.numeric;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WSignedLong;
 
 import java.io.BufferedInputStream;
@@ -13,13 +14,13 @@ public class NumericI64ConstInstr extends Instr {
 
     private long constValue;
 
-    public NumericI64ConstInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public NumericI64ConstInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
         constValue = WSignedLong.read(in, 64);
     }
 
-    public NumericI64ConstInstr(InstrType instrType, long constValue) throws IOException {
+    public NumericI64ConstInstr(long constValue) throws IOException {
-        super(instrType);
+        super(InstrType.I64_CONST);
         this.constValue = constValue;
     }
 

src/main/java/wasm/disassembly/instructions/numeric/NumericInstr.java

@@ -2,6 +2,7 @@ package wasm.disassembly.instructions.numeric;
 
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -9,7 +10,7 @@ import java.io.OutputStream;
 
 public class NumericInstr extends Instr {
 
-    public NumericInstr(BufferedInputStream in, InstrType instrType) throws IOException {
+    public NumericInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException {
         super(instrType);
     }
 

src/main/java/wasm/disassembly/instructions/numeric/TruncSatInstr.java

@@ -3,6 +3,7 @@ package wasm.disassembly.instructions.numeric;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -13,7 +14,7 @@ public class TruncSatInstr extends Instr {
 
     private long type;
 
-    public TruncSatInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public TruncSatInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
         type = WUnsignedInt.read(in, 32);
         if (type < 0 || type > 7) {

src/main/java/wasm/disassembly/instructions/variable/GlobalVariableInstr.java

@@ -3,6 +3,7 @@ package wasm.disassembly.instructions.variable;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.GlobalIdx;
 
 import java.io.BufferedInputStream;
@@ -13,9 +14,9 @@ public class GlobalVariableInstr extends Instr {
 
     private GlobalIdx globalIdx;
 
-    public GlobalVariableInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public GlobalVariableInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
-        globalIdx = new GlobalIdx(in);
+        globalIdx = new GlobalIdx(in, module);
     }
 
     public GlobalVariableInstr(InstrType instrType, GlobalIdx globalIdx) throws IOException {

src/main/java/wasm/disassembly/instructions/variable/LocalVariableInstr.java

@@ -3,6 +3,7 @@ package wasm.disassembly.instructions.variable;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.instructions.Instr;
 import wasm.disassembly.instructions.InstrType;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.LocalIdx;
 
 import java.io.BufferedInputStream;
@@ -13,9 +14,9 @@ public class LocalVariableInstr extends Instr {
 
     private LocalIdx localIdx;
 
-    public LocalVariableInstr(BufferedInputStream in, InstrType instrType) throws IOException, InvalidOpCodeException {
+    public LocalVariableInstr(BufferedInputStream in, InstrType instrType, Module module) throws IOException, InvalidOpCodeException {
         super(instrType);
-        localIdx = new LocalIdx(in);
+        localIdx = new LocalIdx(in, module);
     }
 
     public LocalVariableInstr(InstrType instrType, LocalIdx localIdx) throws IOException {

src/main/java/wasm/disassembly/modules/Module.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.indices.FuncIdx;
 import wasm.disassembly.modules.sections.Section;
 import wasm.disassembly.modules.sections.code.CodeSection;
 import wasm.disassembly.modules.sections.custom.CustomSection;
@@ -17,9 +18,7 @@ import wasm.disassembly.modules.sections.start.StartSection;
 import wasm.disassembly.modules.sections.table.TableSection;
 import wasm.disassembly.modules.sections.type.TypeSection;
 
-import java.io.BufferedInputStream;
+import java.io.*;
-import java.io.IOException;
-import java.io.OutputStream;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -41,6 +40,7 @@ public class Module extends WASMOpCode {
     private DataSection dataSection;
 
     private List<List<CustomSection>> customSectionsList;
+    private List<FuncIdx> allFuncIdxs = new ArrayList<>();
 
     public Module(BufferedInputStream in) throws IOException, InvalidOpCodeException {
         customSectionsList = new ArrayList<>();
@@ -49,29 +49,34 @@ public class Module extends WASMOpCode {
         version = new Version(in);
 
         disassembleCustomSections(in);
-        typeSection = isNextSection(in, 1) ? new TypeSection(in) : null;
+        typeSection = isNextSection(in, 1) ? new TypeSection(in, this) : null;
         disassembleCustomSections(in);
-        importSection = isNextSection(in, 2) ? new ImportSection(in) : null;
+        importSection = isNextSection(in, 2) ? new ImportSection(in, this) : null;
         disassembleCustomSections(in);
-        functionSection = isNextSection(in, 3) ? new FunctionSection(in) : null;
+        functionSection = isNextSection(in, 3) ? new FunctionSection(in, this) : null;
         disassembleCustomSections(in);
-        tableSection = isNextSection(in, 4) ? new TableSection(in) : null;
+        tableSection = isNextSection(in, 4) ? new TableSection(in, this) : null;
         disassembleCustomSections(in);
-        memorySection = isNextSection(in, 5) ? new MemorySection(in) : null;
+        memorySection = isNextSection(in, 5) ? new MemorySection(in, this) : null;
         disassembleCustomSections(in);
-        globalSection = isNextSection(in , 6) ? new GlobalSection(in) : null;
+        globalSection = isNextSection(in , 6) ? new GlobalSection(in, this) : null;
         disassembleCustomSections(in);
-        exportSection = isNextSection(in, 7) ? new ExportSection(in) : null;
+        exportSection = isNextSection(in, 7) ? new ExportSection(in, this) : null;
         disassembleCustomSections(in);
-        startSection = isNextSection(in, 8) ? new StartSection(in) : null;
+        startSection = isNextSection(in, 8) ? new StartSection(in, this) : null;
         disassembleCustomSections(in);
-        elementSection = isNextSection(in, 9) ? new ElementSection(in) : null;
+        elementSection = isNextSection(in, 9) ? new ElementSection(in, this) : null;
         disassembleCustomSections(in);
-        codeSection = isNextSection(in, 10) ? new CodeSection(in) : null;
+        codeSection = isNextSection(in, 10) ? new CodeSection(in, this) : null;
         disassembleCustomSections(in);
-        dataSection = isNextSection(in, 11) ? new DataSection(in) : null;
+        dataSection = isNextSection(in, 11) ? new DataSection(in, this) : null;
         disassembleCustomSections(in);
 
+        in.close();
+    }
+
+    public Module(String fileName) throws IOException, InvalidOpCodeException {
+        this(new BufferedInputStream(new FileInputStream(new File(fileName))));
     }
 
     public Module(Magic magic, Version version, TypeSection typeSection, ImportSection importSection, FunctionSection functionSection, TableSection tableSection, MemorySection memorySection, GlobalSection globalSection, ExportSection exportSection, StartSection startSection, ElementSection elementSection, CodeSection codeSection, DataSection dataSection) {
@@ -94,7 +99,6 @@ public class Module extends WASMOpCode {
             customSectionsList.add(new ArrayList<>());
         }
     }
-
     public Module(TypeSection typeSection, ImportSection importSection, FunctionSection functionSection, TableSection tableSection, MemorySection memorySection, GlobalSection globalSection, ExportSection exportSection, StartSection startSection, ElementSection elementSection, CodeSection codeSection, DataSection dataSection, List<List<CustomSection>> customSectionsList) {
         this(new Magic(), new Version(), typeSection, importSection, functionSection, tableSection, memorySection,
                 globalSection, exportSection, startSection, elementSection, codeSection, dataSection);
@@ -104,7 +108,7 @@ public class Module extends WASMOpCode {
         List<CustomSection> customSections = new ArrayList<>();
 
         while (isNextSection(in, 0)) {
-            customSections.add(CustomSectionFactory.get(in));
+            customSections.add(CustomSectionFactory.get(in, this));
         }
 
         in.reset();
@@ -144,6 +148,11 @@ public class Module extends WASMOpCode {
         }
     }
 
+    public void assembleToFile(String fileName) throws IOException, InvalidOpCodeException {
+        FileOutputStream habAssembled = new FileOutputStream(fileName);
+        assemble(habAssembled);
+        habAssembled.close();
+    }
 
     public Magic getMagic() {
         return magic;
@@ -256,4 +265,8 @@ public class Module extends WASMOpCode {
     public void setCustomSectionsList(List<List<CustomSection>> customSectionsList) {
         this.customSectionsList = customSectionsList;
     }
+
+    public List<FuncIdx> getAllFuncIdxs() {
+        return allFuncIdxs;
+    }
 }

src/main/java/wasm/disassembly/modules/indices/FuncIdx.java

@@ -1,38 +1,41 @@
 package wasm.disassembly.modules.indices;
 
+import com.sun.org.apache.xpath.internal.functions.FuncId;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
 import java.io.OutputStream;
+import java.util.ArrayList;
+import java.util.List;
 
 public class FuncIdx extends WASMOpCode {
 
-
-    public static int OFFSET = 0;
-
     private long x;
 
-    public FuncIdx(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public FuncIdx(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         x = WUnsignedInt.read(in, 32);
+        module.getAllFuncIdxs().add(this);
     }
 
-    public FuncIdx(long x) {
+    public FuncIdx(long x, Module module) {
-        this.x = x - OFFSET;
+        this.x = x;
+        module.getAllFuncIdxs().add(this);
     }
 
     @Override
     public void assemble(OutputStream out) throws IOException, InvalidOpCodeException {
-        WUnsignedInt.write(x + OFFSET, out, 32);
+        WUnsignedInt.write(x, out, 32);
     }
 
     public long getX() {
-        return x + OFFSET;
+        return x;
     }
 
     public void setX(long x) {
-        this.x = x - OFFSET;
+        this.x = x;
     }
 }

src/main/java/wasm/disassembly/modules/indices/GlobalIdx.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.indices;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -12,7 +13,7 @@ public class GlobalIdx extends WASMOpCode {
 
     private long x;
 
-    public GlobalIdx(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public GlobalIdx(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         x = WUnsignedInt.read(in, 32);
     }
 

src/main/java/wasm/disassembly/modules/indices/LabelIdx.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.indices;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -12,7 +13,7 @@ public class LabelIdx extends WASMOpCode {
 
     private long l;
 
-    public LabelIdx(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public LabelIdx(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         l = WUnsignedInt.read(in, 32);
     }
 

src/main/java/wasm/disassembly/modules/indices/LocalIdx.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.indices;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -12,7 +13,7 @@ public class LocalIdx extends WASMOpCode {
 
     private long x;
 
-    public LocalIdx(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public LocalIdx(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         x = WUnsignedInt.read(in, 32);
     }
 

src/main/java/wasm/disassembly/modules/indices/MemIdx.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.indices;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -12,7 +13,7 @@ public class MemIdx extends WASMOpCode {
 
     private long x;
 
-    public MemIdx(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public MemIdx(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         x = WUnsignedInt.read(in, 32);
     }
 

src/main/java/wasm/disassembly/modules/indices/TableIdx.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.indices;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -12,7 +13,7 @@ public class TableIdx extends WASMOpCode {
 
     private long x;
 
-    public TableIdx(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public TableIdx(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         x = WUnsignedInt.read(in, 32);
     }
 

src/main/java/wasm/disassembly/modules/indices/TypeIdx.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.indices;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -12,7 +13,7 @@ public class TypeIdx extends WASMOpCode {
 
     private long x;
 
-    public TypeIdx(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public TypeIdx(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         x = WUnsignedInt.read(in, 32);
     }
 

src/main/java/wasm/disassembly/modules/misc/Function.java

@@ -0,0 +1,63 @@
+package wasm.disassembly.modules.misc;
+
+import wasm.disassembly.instructions.Expression;
+import wasm.disassembly.modules.Module;
+import wasm.disassembly.modules.indices.FuncIdx;
+import wasm.disassembly.modules.indices.TypeIdx;
+import wasm.disassembly.modules.sections.code.Code;
+import wasm.disassembly.modules.sections.code.Func;
+import wasm.disassembly.types.FuncType;
+import wasm.disassembly.types.ValType;
+
+import java.util.List;
+
+public class Function {
+
+    private FuncType funcType;
+    private List<ValType> locals;
+    private Expression code;
+
+    public Function(FuncType funcType, List<ValType> locals, Expression code) {
+        this.funcType = funcType;
+        this.locals = locals;
+        this.code = code;
+    }
+
+    public FuncIdx addToModule(Module module) {
+        TypeIdx typeIdx = module.getTypeSection().getTypeIdxForFuncType(funcType);
+        ValType[] valTypeArr = locals.toArray(new ValType[0]);
+        Func func = new Func(valTypeArr, code);
+
+        module.getFunctionSection().getTypeIdxVector().add(typeIdx);
+        module.getCodeSection().getCodesEntries().add(new Code(func));
+        return new FuncIdx(
+                module.getImportSection().getTotalFuncImports() + module.getCodeSection().getCodesEntries().size() - 1,
+                module
+        );
+    }
+
+
+    public FuncType getFuncType() {
+        return funcType;
+    }
+
+    public void setFuncType(FuncType funcType) {
+        this.funcType = funcType;
+    }
+
+    public List<ValType> getLocals() {
+        return locals;
+    }
+
+    public void setLocals(List<ValType> locals) {
+        this.locals = locals;
+    }
+
+    public Expression getCode() {
+        return code;
+    }
+
+    public void setCode(Expression code) {
+        this.code = code;
+    }
+}

src/main/java/wasm/disassembly/modules/sections/code/Code.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.code;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -13,9 +14,9 @@ public class Code extends WASMOpCode {
 
     private Func code;
 
-    public Code(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Code(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         long sizeInBytes = WUnsignedInt.read(in, 32);   // don't use
-        code = new Func(in);
+        code = new Func(in, module);
     }
 
     public Code(Func code) {

src/main/java/wasm/disassembly/modules/sections/code/CodeSection.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.code;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.conventions.Vector;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.sections.Section;
 
 import java.io.BufferedInputStream;
@@ -16,9 +17,9 @@ public class CodeSection extends Section {
 
     private Vector<Code> codesEntries;
 
-    public CodeSection(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public CodeSection(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         super(in, CODE_SECTION_ID);
-        codesEntries = new Vector<>(in, Code::new);
+        codesEntries = new Vector<>(in, Code::new, module);
     }
 
     public CodeSection(List<Code> codesEntries) {

src/main/java/wasm/disassembly/modules/sections/code/Func.java

@@ -4,10 +4,13 @@ import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
 import wasm.disassembly.conventions.Vector;
 import wasm.disassembly.instructions.Expression;
+import wasm.disassembly.modules.Module;
+import wasm.disassembly.types.ValType;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
 import java.io.OutputStream;
+import java.util.ArrayList;
 import java.util.List;
 
 public class Func extends WASMOpCode {
@@ -16,9 +19,9 @@ public class Func extends WASMOpCode {
     private Expression expression;
 
 
-    public Func(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Func(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
-        localss = new Vector<>(in, Locals::new);
+        localss = new Vector<>(in, Locals::new, module);
-        expression = new Expression(in);
+        expression = new Expression(in, module);
     }
 
     public Func(List<Locals> localss, Expression expression) {
@@ -26,6 +29,11 @@ public class Func extends WASMOpCode {
         this.expression = expression;
     }
 
+    public Func(ValType[] localVariables, Expression expression) {
+        setLocalVariables(localVariables);
+        this.expression = expression;
+    }
+
     @Override
     public void assemble(OutputStream out) throws IOException, InvalidOpCodeException {
         localss.assemble(out);
@@ -47,4 +55,21 @@ public class Func extends WASMOpCode {
     public void setExpression(Expression expression) {
         this.expression = expression;
     }
+
+    public void setLocalVariables(ValType[] locals) {
+        List<Locals> localss = new ArrayList<>();
+
+        Locals current = null;
+        for (ValType valType : locals) {
+            if (current == null || current.getValType() != valType) {
+                if (current != null) localss.add(current);
+                current = new Locals(1, valType);
+            }
+            else {
+                current.setAmount(current.getAmount() + 1);
+            }
+        }
+        if (current != null) localss.add(current);
+        this.localss = new Vector<>(localss);
+    }
 }

src/main/java/wasm/disassembly/modules/sections/code/Locals.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.code;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.types.ValType;
 import wasm.disassembly.values.WUnsignedInt;
 
@@ -14,12 +15,12 @@ public class Locals extends WASMOpCode {
     private long amount;
     private ValType valType;
 
-    public Locals(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Locals(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         amount = WUnsignedInt.read(in, 32);
         valType = ValType.from_val(in.read());
     }
 
-    public Locals(long amount, ValType valType) throws InvalidOpCodeException {
+    public Locals(long amount, ValType valType) {
         this.amount = amount;
         this.valType = valType;
     }

src/main/java/wasm/disassembly/modules/sections/custom/CustomSection.java

@@ -1,6 +1,7 @@
 package wasm.disassembly.modules.sections.custom;
 
 import wasm.disassembly.InvalidOpCodeException;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.sections.Section;
 import wasm.disassembly.values.WName;
 
@@ -14,7 +15,7 @@ public abstract class CustomSection extends Section {
 
     private String name;
 
-    public CustomSection(long size, String name) throws IOException, InvalidOpCodeException {
+    public CustomSection(Module module, long size, String name) throws IOException, InvalidOpCodeException {
         super(CUSTOM_SECTION_ID, size);
         this.name = name;
     }

src/main/java/wasm/disassembly/modules/sections/custom/CustomSectionFactory.java

@@ -1,6 +1,7 @@
 package wasm.disassembly.modules.sections.custom;
 
 import wasm.disassembly.InvalidOpCodeException;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WName;
 import wasm.disassembly.values.WUnsignedInt;
 
@@ -9,12 +10,12 @@ import java.io.IOException;
 
 public class CustomSectionFactory {
 
-    public static CustomSection get(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public static CustomSection get(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         long size = WUnsignedInt.read(in, 32);
         String name = WName.read(in);
 
         // select implementation
 
-        return new UnImplementedCustomSection(in, size, name);
+        return new UnImplementedCustomSection(in, module, size, name);
     }
 }

src/main/java/wasm/disassembly/modules/sections/custom/UnImplementedCustomSection.java

@@ -1,6 +1,7 @@
 package wasm.disassembly.modules.sections.custom;
 
 import wasm.disassembly.InvalidOpCodeException;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WName;
 
 import java.io.BufferedInputStream;
@@ -13,8 +14,8 @@ public class UnImplementedCustomSection extends CustomSection {
 
     private byte[] bytes;
 
-    public UnImplementedCustomSection(BufferedInputStream in, long size, String name) throws IOException, InvalidOpCodeException {
+    public UnImplementedCustomSection(BufferedInputStream in, Module module, long size, String name) throws IOException, InvalidOpCodeException {
-        super(size, name);
+        super(module, size, name);
 
         ByteArrayOutputStream nameOut = new ByteArrayOutputStream();
         WName.write(name, nameOut);

src/main/java/wasm/disassembly/modules/sections/data/Data.java

@@ -3,6 +3,7 @@ package wasm.disassembly.modules.sections.data;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
 import wasm.disassembly.instructions.Expression;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.MemIdx;
 import wasm.disassembly.values.WUnsignedInt;
 
@@ -17,9 +18,9 @@ public class Data extends WASMOpCode {
     private byte[] data;
 
 
-    public Data(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Data(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
-        dataMemId = new MemIdx(in);
+        dataMemId = new MemIdx(in, module);
-        offset = new Expression(in);
+        offset = new Expression(in, module);
         long length = WUnsignedInt.read(in, 32);
         data = new byte[(int)length];
         in.read(data);

src/main/java/wasm/disassembly/modules/sections/data/DataSection.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.data;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.conventions.Vector;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.sections.Section;
 
 import java.io.BufferedInputStream;
@@ -16,9 +17,9 @@ public class DataSection extends Section {
 
     private Vector<Data> dataSegments;
 
-    public DataSection(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public DataSection(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         super(in, DATA_SECTION_ID);
-        dataSegments = new Vector<>(in, Data::new);
+        dataSegments = new Vector<>(in, Data::new, module);
     }
 
     public DataSection(List<Data> dataSegments) {

src/main/java/wasm/disassembly/modules/sections/element/Elem.java

@@ -4,6 +4,7 @@ import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
 import wasm.disassembly.conventions.Vector;
 import wasm.disassembly.instructions.Expression;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.FuncIdx;
 import wasm.disassembly.modules.indices.TableIdx;
 
@@ -17,10 +18,10 @@ public class Elem extends WASMOpCode {
     private Expression offset;
     private Vector<FuncIdx> init;
 
-    public Elem(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Elem(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
-        tableIdx = new TableIdx(in);
+        tableIdx = new TableIdx(in, module);
-        offset = new Expression(in);
+        offset = new Expression(in, module);
-        init = new Vector<>(in, FuncIdx::new);
+        init = new Vector<>(in, FuncIdx::new, module);
     }
 
     public Elem(TableIdx tableIdx, Expression offset, Vector<FuncIdx> init) {

src/main/java/wasm/disassembly/modules/sections/element/ElementSection.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.element;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.conventions.Vector;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.sections.Section;
 
 import java.io.BufferedInputStream;
@@ -15,9 +16,9 @@ public class ElementSection extends Section {
 
     private Vector<Elem> elementSegments;
 
-    public ElementSection(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public ElementSection(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         super(in, ELEMENT_SECTION_ID);
-        elementSegments = new Vector<>(in, Elem::new);
+        elementSegments = new Vector<>(in, Elem::new, module);
     }
 
     public ElementSection(List<Elem> elementSegments) {

src/main/java/wasm/disassembly/modules/sections/export/Export.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.export;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WName;
 
 import java.io.BufferedInputStream;
@@ -13,9 +14,9 @@ public class Export extends WASMOpCode {
     private String name;
     private ExportDesc exportDesc;
 
-    public Export(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Export(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         name = WName.read(in);
-        exportDesc = new ExportDesc(in);
+        exportDesc = new ExportDesc(in, module);
     }
 
     public Export(String name, ExportDesc exportDesc) {

src/main/java/wasm/disassembly/modules/sections/export/ExportDesc.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.export;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.FuncIdx;
 import wasm.disassembly.modules.indices.GlobalIdx;
 import wasm.disassembly.modules.indices.MemIdx;
@@ -17,16 +18,16 @@ public class ExportDesc extends WASMOpCode {
     private int exportType;
 
 
-    public ExportDesc(BufferedInputStream in) throws InvalidOpCodeException, IOException {
+    public ExportDesc(BufferedInputStream in, Module module) throws InvalidOpCodeException, IOException {
         exportType = in.read();
         if (exportType < 0x00 || exportType > 0x03) {
             throw new InvalidOpCodeException("invalid importdesc type");
         }
 
-        exportValue = exportType == 0x00 ? new FuncIdx(in) :
+        exportValue = exportType == 0x00 ? new FuncIdx(in, module) :
-                (exportType == 0x01 ? new TableIdx(in) :
+                (exportType == 0x01 ? new TableIdx(in, module) :
-                        (exportType == 0x02 ? new MemIdx(in) :
+                        (exportType == 0x02 ? new MemIdx(in, module) :
-                                new GlobalIdx(in)));
+                                new GlobalIdx(in, module)));
     }
 
     public ExportDesc(WASMOpCode exportValue, int exportType) {

src/main/java/wasm/disassembly/modules/sections/export/ExportSection.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.export;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.conventions.Vector;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.sections.Section;
 
 import java.io.BufferedInputStream;
@@ -15,9 +16,9 @@ public class ExportSection extends Section {
 
     private Vector<Export> exports;
 
-    public ExportSection(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public ExportSection(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         super(in, EXPORT_SECTION_ID);
-        exports = new Vector<>(in, Export::new);
+        exports = new Vector<>(in, Export::new, module);
     }
 
     public ExportSection(List<Export> exports) {

src/main/java/wasm/disassembly/modules/sections/function/FunctionSection.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.function;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.conventions.Vector;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.TypeIdx;
 import wasm.disassembly.modules.sections.Section;
 
@@ -17,9 +18,9 @@ public class FunctionSection extends Section {
     private Vector<TypeIdx> typeIdxVector;
 
 
-    public FunctionSection(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public FunctionSection(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         super(in, FUNCTION_SECTION_ID);
-        typeIdxVector = new Vector<>(in, TypeIdx::new);
+        typeIdxVector = new Vector<>(in, TypeIdx::new, module);
     }
 
     public FunctionSection(List<TypeIdx> typeIdxList) {

src/main/java/wasm/disassembly/modules/sections/global/Global.java

@@ -3,6 +3,7 @@ package wasm.disassembly.modules.sections.global;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
 import wasm.disassembly.instructions.Expression;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.types.GlobalType;
 
 import java.io.BufferedInputStream;
@@ -14,9 +15,9 @@ public class Global extends WASMOpCode {
     private GlobalType globalType;
     private Expression expression;
 
-    public Global(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Global(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
-        globalType = new GlobalType(in);
+        globalType = new GlobalType(in, module);
-        expression = new Expression(in);
+        expression = new Expression(in, module);
     }
 
     public Global(GlobalType globalType, Expression expression) {

src/main/java/wasm/disassembly/modules/sections/global/GlobalSection.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.global;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.conventions.Vector;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.sections.Section;
 
 import java.io.BufferedInputStream;
@@ -16,9 +17,9 @@ public class GlobalSection extends Section {
     private Vector<Global> globals;
 
 
-    public GlobalSection(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public GlobalSection(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         super(in, GLOBAL_SECTION_ID);
-        globals = new Vector<>(in, Global::new);
+        globals = new Vector<>(in, Global::new, module);
     }
 
     public GlobalSection(List<Global> globals) {

src/main/java/wasm/disassembly/modules/sections/imprt/Import.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.imprt;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WName;
 
 import java.io.BufferedInputStream;
@@ -14,10 +15,10 @@ public class Import extends WASMOpCode {
     private String name;
     private ImportDesc importDescription;
 
-    public Import(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Import(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
-        module = WName.read(in);
+        this.module = WName.read(in);
         name = WName.read(in);
-        importDescription = new ImportDesc(in);
+        importDescription = new ImportDesc(in, module);
     }
 
     public Import(String module, String name, ImportDesc importDescription) {

src/main/java/wasm/disassembly/modules/sections/imprt/ImportDesc.java

@@ -2,6 +2,8 @@ package wasm.disassembly.modules.sections.imprt;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
+import wasm.disassembly.modules.indices.FuncIdx;
 import wasm.disassembly.modules.indices.TypeIdx;
 import wasm.disassembly.types.GlobalType;
 import wasm.disassembly.types.MemType;
@@ -16,16 +18,16 @@ public class ImportDesc extends WASMOpCode {
     private WASMOpCode importValue;
     private int importType;
 
-    public ImportDesc(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public ImportDesc(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         importType = in.read();
         if (importType < 0x00 || importType > 0x03) {
             throw new InvalidOpCodeException("invalid importdesc type");
         }
 
-        importValue = importType == 0x00 ? new TypeIdx(in) :
+        importValue = importType == 0x00 ? new TypeIdx(in, module) :
-                (importType == 0x01 ? new TableType(in) :
+                (importType == 0x01 ? new TableType(in, module) :
-                        (importType == 0x02 ? new MemType(in) :
+                        (importType == 0x02 ? new MemType(in, module) :
-                                new GlobalType(in)));
+                                new GlobalType(in, module)));
     }
 
     public ImportDesc(WASMOpCode importValue, int importType) {

src/main/java/wasm/disassembly/modules/sections/imprt/ImportSection.java

@@ -1,7 +1,9 @@
 package wasm.disassembly.modules.sections.imprt;
 
+import com.sun.org.apache.xpath.internal.functions.FuncId;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.conventions.Vector;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.FuncIdx;
 import wasm.disassembly.modules.sections.Section;
 
@@ -14,13 +16,24 @@ import java.util.List;
 public class ImportSection extends Section {
 
     public static final int IMPORT_SECTION_ID = 2;
+    private Module module;
+
+    private int totalFuncImports;
 
     private Vector<Import> imports;
 
 
-    public ImportSection(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public ImportSection(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         super(in, IMPORT_SECTION_ID);
-        imports = new Vector<>(in, Import::new);
+        this.module = module;
+        imports = new Vector<>(in, Import::new, module);
+
+        totalFuncImports = 0;
+        for (Import imprt : imports.getElements()) {
+            if (imprt.getImportDescription().getImportType() == 0) {
+                totalFuncImports++;
+            }
+        }
     }
 
     public ImportSection(List<Import> imports) {
@@ -41,11 +54,28 @@ public class ImportSection extends Section {
         this.imports = new Vector<>(imports);
     }
 
-    public void importFunctions(List<Import> functions) {
+    public List<FuncIdx> importFunctions(List<Import> functions) throws InvalidOpCodeException {
-        List<Import> newImports = new ArrayList<>(functions);
+        for (Import imprt : functions) {
-        newImports.addAll(imports.getElements());
+            if (imprt.getImportDescription().getImportType() != 0) {
+                throw new InvalidOpCodeException("Tried to import non-function as function");
+            }
+        }
 
-        setImports(newImports);
+        for (FuncIdx funcIdx : module.getAllFuncIdxs()) {
-        FuncIdx.OFFSET += functions.size();
+            if (funcIdx.getX() >= totalFuncImports) {
+                funcIdx.setX(funcIdx.getX() + functions.size());
+            }
+        }
+        List<FuncIdx> newFuncIdxs = new ArrayList<>();
+        for (long i = totalFuncImports; i < totalFuncImports + functions.size(); i++) {
+            newFuncIdxs.add(new FuncIdx(i, module));
+        }
+        imports.getElements().addAll(functions);
+        totalFuncImports += functions.size();
+        return newFuncIdxs;
+    }
+
+    public int getTotalFuncImports() {
+        return totalFuncImports;
     }
 }

src/main/java/wasm/disassembly/modules/sections/memory/Mem.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.memory;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.types.MemType;
 
 import java.io.BufferedInputStream;
@@ -12,8 +13,8 @@ public class Mem extends WASMOpCode {
 
     private MemType memType;
 
-    public Mem(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Mem(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
-        memType = new MemType(in);
+        memType = new MemType(in, module);
     }
 
     public Mem(MemType memType) {

src/main/java/wasm/disassembly/modules/sections/memory/MemorySection.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.memory;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.conventions.Vector;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.sections.Section;
 
 import java.io.BufferedInputStream;
@@ -16,9 +17,9 @@ public class MemorySection extends Section {
     private Vector<Mem> memories;
 
 
-    public MemorySection(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public MemorySection(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         super(in, MEMORY_SECTION_ID);
-        memories = new Vector<>(in, Mem::new);
+        memories = new Vector<>(in, Mem::new, module);
     }
 
     public MemorySection(List<Mem> memories) {

src/main/java/wasm/disassembly/modules/sections/start/Start.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.start;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.indices.FuncIdx;
 
 import java.io.BufferedInputStream;
@@ -12,8 +13,8 @@ public class Start extends WASMOpCode {
 
     private FuncIdx funcIdx;
 
-    public Start(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Start(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
-        funcIdx = new FuncIdx(in);
+        funcIdx = new FuncIdx(in, module);
     }
 
     public Start(FuncIdx funcIdx) {

src/main/java/wasm/disassembly/modules/sections/start/StartSection.java

@@ -1,6 +1,7 @@
 package wasm.disassembly.modules.sections.start;
 
 import wasm.disassembly.InvalidOpCodeException;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.sections.Section;
 
 import java.io.BufferedInputStream;
@@ -13,9 +14,9 @@ public class StartSection extends Section {
 
     private Start start;
 
-    public StartSection(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public StartSection(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         super(in, START_SECTION_ID);
-        start = new Start(in);
+        start = new Start(in, module);
     }
 
     public StartSection(Start start) {

src/main/java/wasm/disassembly/modules/sections/table/Table.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.table;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.types.TableType;
 
 import java.io.BufferedInputStream;
@@ -12,8 +13,8 @@ public class Table extends WASMOpCode {
 
     private TableType tableType;
 
-    public Table(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Table(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
-        tableType = new TableType(in);
+        tableType = new TableType(in, module);
     }
 
     public Table(TableType tableType) {

src/main/java/wasm/disassembly/modules/sections/table/TableSection.java

@@ -2,6 +2,7 @@ package wasm.disassembly.modules.sections.table;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.conventions.Vector;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.modules.sections.Section;
 
 import java.io.BufferedInputStream;
@@ -16,9 +17,9 @@ public class TableSection extends Section {
     private Vector<Table> tables;
 
 
-    public TableSection(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public TableSection(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         super(in, TABLE_SECTION_ID);
-        tables = new Vector<>(in, Table::new);
+        tables = new Vector<>(in, Table::new, module);
     }
 
     public TableSection(List<Table> tables) {

src/main/java/wasm/disassembly/modules/sections/type/TypeSection.java

@@ -2,6 +2,8 @@ package wasm.disassembly.modules.sections.type;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.conventions.Vector;
+import wasm.disassembly.modules.Module;
+import wasm.disassembly.modules.indices.TypeIdx;
 import wasm.disassembly.modules.sections.Section;
 import wasm.disassembly.types.FuncType;
 
@@ -17,9 +19,9 @@ public class TypeSection extends Section {
     private Vector<FuncType> functionTypes;
 
 
-    public TypeSection(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public TypeSection(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         super(in, TYPE_SECTION_ID);
-        functionTypes = new Vector<>(in, FuncType::new);
+        functionTypes = new Vector<>(in, FuncType::new, module);
     }
 
     public TypeSection(List<FuncType> functionTypes) {
@@ -39,4 +41,16 @@ public class TypeSection extends Section {
     public void setFunctionTypes(List<FuncType> functionTypes) {
         this.functionTypes = new Vector<>(functionTypes);
     }
+
+    public TypeIdx getTypeIdxForFuncType(FuncType newFuncType) {
+        for (int i = 0; i < getFunctionTypes().size(); i++) {
+            FuncType funcType = getFunctionTypes().get(i);
+            if (funcType.equals(newFuncType)) {
+                return new TypeIdx(i);
+            }
+        }
+
+        getFunctionTypes().add(newFuncType);
+        return new TypeIdx(getFunctionTypes().size() - 1);
+    }
 }

src/main/java/wasm/disassembly/types/FuncType.java

@@ -2,6 +2,8 @@ package wasm.disassembly.types;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
+import wasm.disassembly.modules.sections.code.Func;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -12,11 +14,11 @@ public class FuncType extends WASMOpCode {
     private ResultType parameterType;
     private ResultType resultType;
 
-    public FuncType(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public FuncType(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         if (in.read() != 0x60) throw new InvalidOpCodeException("Function types must be encoded with 0x60");
 
-        parameterType = new ResultType(in);
+        parameterType = new ResultType(in, module);
-        resultType = new ResultType(in);
+        resultType = new ResultType(in, module);
     }
 
     public FuncType(ResultType parameterType, ResultType resultType) {
@@ -46,4 +48,16 @@ public class FuncType extends WASMOpCode {
     public void setResultType(ResultType resultType) {
         this.resultType = resultType;
     }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (!(obj instanceof FuncType)) {
+            return false;
+        }
+
+        FuncType other = (FuncType) obj;
+
+        return parameterType.equals(other.parameterType) &&
+                resultType.equals(other.resultType);
+    }
 }

src/main/java/wasm/disassembly/types/GlobalType.java

@@ -2,6 +2,7 @@ package wasm.disassembly.types;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -12,7 +13,7 @@ public class GlobalType extends WASMOpCode {
     private ValType valType;
     private Mutability mutability;
 
-    public GlobalType(BufferedInputStream in) throws IOException {
+    public GlobalType(BufferedInputStream in, Module module) throws IOException {
         valType = ValType.from_val(in.read());
         mutability = Mutability.from_val(in.read());
     }

src/main/java/wasm/disassembly/types/Limits.java

@@ -2,6 +2,7 @@ package wasm.disassembly.types;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 import wasm.disassembly.values.WUnsignedInt;
 
 import java.io.BufferedInputStream;
@@ -13,7 +14,7 @@ public class Limits extends WASMOpCode {
     private long min;
     private long max;
 
-    public Limits(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public Limits(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         int flag = in.read();
         if (flag == 0x00) {
             min = WUnsignedInt.read(in, 32);

src/main/java/wasm/disassembly/types/MemType.java

@@ -2,6 +2,7 @@ package wasm.disassembly.types;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -11,8 +12,8 @@ public class MemType extends WASMOpCode {
 
     private Limits limits;
 
-    public MemType(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public MemType(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
-        limits = new Limits(in);
+        limits = new Limits(in, module);
     }
 
     public MemType(Limits limits) {

src/main/java/wasm/disassembly/types/ResultType.java

@@ -3,6 +3,7 @@ package wasm.disassembly.types;
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
 import wasm.disassembly.conventions.CustomVector;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -13,11 +14,12 @@ public class ResultType extends WASMOpCode {
 
     private CustomVector<ValType> vector;
 
-    public ResultType(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public ResultType(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         vector = new CustomVector<>(
                 in,
-                in1 -> ValType.from_val(in1.read()),
+                (in1, m) -> ValType.from_val(in1.read()),
-                (valType, out) -> out.write(valType.val)
+                (valType, out) -> out.write(valType.val),
+                module
         );
     }
 
@@ -48,4 +50,14 @@ public class ResultType extends WASMOpCode {
     public void setVector(CustomVector<ValType> vector) {
         this.vector = vector;
     }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (!(obj instanceof ResultType)) {
+            return false;
+        }
+
+        ResultType other = (ResultType) obj;
+        return vector.getElements().equals(other.vector.getElements());
+    }
 }

src/main/java/wasm/disassembly/types/TableType.java

@@ -2,6 +2,7 @@ package wasm.disassembly.types;
 
 import wasm.disassembly.InvalidOpCodeException;
 import wasm.disassembly.WASMOpCode;
+import wasm.disassembly.modules.Module;
 
 import java.io.BufferedInputStream;
 import java.io.IOException;
@@ -12,12 +13,12 @@ public class TableType extends WASMOpCode {
     private ElemType elemType;
     private Limits limits;
 
-    public TableType(BufferedInputStream in) throws IOException, InvalidOpCodeException {
+    public TableType(BufferedInputStream in, Module module) throws IOException, InvalidOpCodeException {
         elemType = ElemType.from_val(in.read());
         if (elemType == null) {
             throw new InvalidOpCodeException("No such element type");
         }
-        limits = new Limits(in);
+        limits = new Limits(in, module);
     }
 
     public TableType(ElemType elemType, Limits limits) {

src/main/java/wasm/disassembly/values/WByte.java

@@ -1,32 +0,0 @@
-package wasm.disassembly.values;
-
-import wasm.disassembly.WASMOpCode;
-
-import java.io.BufferedInputStream;
-import java.io.IOException;
-import java.io.OutputStream;
-
-public class WByte extends WASMOpCode {
-
-    private int b;
-
-    public WByte(BufferedInputStream inputStream) throws IOException {
-        b = inputStream.read();
-    }
-
-    public WByte(int b) {
-        this.b = b;
-    }
-
-    public void assemble(OutputStream out) throws IOException {
-        out.write(b);
-    }
-
-    public int getB() {
-        return b;
-    }
-
-    public void setB(int b) {
-        this.b = b;
-    }
-}