/*
* Copyright 2017 - 2018 Volker Berlin (i-net software)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package de.inetsoftware.jwebassembly.binary;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import de.inetsoftware.classparser.MethodInfo;
import de.inetsoftware.jwebassembly.WasmException;
import de.inetsoftware.jwebassembly.module.WasmBlockOperator;
import de.inetsoftware.jwebassembly.module.ModuleWriter;
import de.inetsoftware.jwebassembly.module.NumericOperator;
import de.inetsoftware.jwebassembly.module.ValueType;
import de.inetsoftware.jwebassembly.module.ValueTypeConvertion;
/**
* Module Writer for binary format. http://webassembly.org/docs/binary-encoding/
*
* @author Volker Berlin
*/
public class BinaryModuleWriter extends ModuleWriter implements InstructionOpcodes {
private static final byte[] WASM_BINARY_MAGIC = { 0, 'a', 's', 'm' };
private static final int WASM_BINARY_VERSION = 1;
private WasmOutputStream wasm;
private WasmOutputStream codeStream = new WasmOutputStream();
private WasmOutputStream functionsStream = new WasmOutputStream();
private List<FunctionType> functionTypes = new ArrayList<>();
private Map<String, Function> functions = new LinkedHashMap<>();
private Map<String, String> exports = new LinkedHashMap<>();
private Function function;
private FunctionType functionType;
/**
* Create new instance.
*
* @param output
* the target for the module data.
* @throws IOException
* if any I/O error occur
*/
public BinaryModuleWriter( OutputStream output ) throws IOException {
wasm = new WasmOutputStream( output );
}
/**
* {@inheritDoc}
*/
@Override
public void close() throws IOException {
wasm.write( WASM_BINARY_MAGIC );
wasm.writeInt32( WASM_BINARY_VERSION );
writeTypeSection();
writeFunctionSection();
writeExportSection();
writeCodeSection();
wasm.close();
}
/**
* Write the type section to the output. This section contains the signatures of the functions.
*
* @throws IOException
* if any I/O error occur
*/
private void writeTypeSection() throws IOException {
int count = functionTypes.size();
if( count > 0 ) {
WasmOutputStream stream = new WasmOutputStream();
stream.writeVaruint32( count );
for( FunctionType type : functionTypes ) {
stream.writeVarint( ValueType.func.getCode() );
stream.writeVaruint32( type.params.size() );
for( ValueType valueType : type.params ) {
stream.writeVarint( valueType.getCode() );
}
if( type.result == null ) {
stream.writeVaruint32( 0 );
} else {
stream.writeVaruint32( 1 );
stream.writeVarint( type.result.getCode() );
}
}
wasm.writeSection( SectionType.Type, stream, null );
}
}
/**
* Write the function section to the output. This section contains a mapping from the function index to the type signature index.
*
* @throws IOException
* if any I/O error occur
*/
private void writeFunctionSection() throws IOException {
int count = functions.size();
if( count > 0 ) {
WasmOutputStream stream = new WasmOutputStream();
stream.writeVaruint32( count );
for( Function func : functions.values() ) {
stream.writeVaruint32( func.typeId );
}
wasm.writeSection( SectionType.Function, stream, null );
}
}
/**
* Write the export section to the output. This section contains a mapping from the external index to the type signature index.
*
* @throws IOException
* if any I/O error occur
*/
private void writeExportSection() throws IOException {
int count = exports.size();
if( count > 0 ) {
WasmOutputStream stream = new WasmOutputStream();
stream.writeVaruint32( count );
for( Map.Entry<String,String> entry : exports.entrySet() ) {
String exportName = entry.getKey();
byte[] bytes = exportName.getBytes( StandardCharsets.UTF_8 );
stream.writeVaruint32( bytes.length );
stream.write( bytes );
stream.writeVaruint32( ExternalKind.Function.ordinal() );
int id = functions.get( entry.getValue() ).id;
stream.writeVaruint32( id );
}
wasm.writeSection( SectionType.Export, stream, null );
}
}
/**
* Write the code section to the output. This section contains the byte code.
*
* @throws IOException
* if any I/O error occur
*/
private void writeCodeSection() throws IOException {
int size = functions.size();
if( size == 0 ) {
return;
}
WasmOutputStream stream = new WasmOutputStream();
stream.writeVaruint32( size );
functionsStream.writeTo( stream );
wasm.writeSection( SectionType.Code, stream, null );
}
/**
* {@inheritDoc}
*/
protected void prepareMethod( MethodInfo method ) throws WasmException {
String methodName = method.getName();
String className = method.getDeclaringClassFile().getThisClass().getName();
String fullName = className + '.' + methodName;
String signatureName = fullName + method.getDescription();
Function function = new Function();
function.id = functions.size();
functions.put( signatureName, function );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeExport( String signatureName, String methodName, String exportName ) throws IOException {
exports.put( exportName, signatureName );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeMethodStart( String signatureName, String name ) throws IOException {
function = functions.get( signatureName );
functionType = new FunctionType();
codeStream.reset();
}
/**
* {@inheritDoc}
*/
@Override
protected void writeMethodParam( String kind, ValueType valueType ) throws IOException {
switch( kind ) {
case "param":
functionType.params.add( valueType );
return;
case "result":
functionType.result = valueType;
return;
}
}
/**
* {@inheritDoc}
*/
@Override
protected void writeMethodFinish( List<ValueType> locals ) throws IOException {
// TODO optimize and search for duplicates
function.typeId = functionTypes.size();
functionTypes.add( functionType );
WasmOutputStream localsStream = new WasmOutputStream();
localsStream.writeVaruint32( locals.size() );
for( ValueType valueType : locals ) {
localsStream.writeVaruint32( 1 ); // TODO optimize, write the count of same types.
localsStream.writeVarint( valueType.getCode() );
}
functionsStream.writeVaruint32( localsStream.size() + codeStream.size() + 1 );
localsStream.writeTo( functionsStream );
codeStream.writeTo( functionsStream );
functionsStream.write( END );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeConstInt( int value ) throws IOException {
codeStream.write( I32_CONST );
codeStream.writeVarint( value );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeConstLong( long value ) throws IOException {
codeStream.write( I64_CONST );
codeStream.writeVarint( value );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeConstFloat( float value ) throws IOException {
codeStream.write( F32_CONST );
codeStream.writeFloat( value );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeConstDouble( double value ) throws IOException {
codeStream.write( F64_CONST );
codeStream.writeDouble( value );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeLoad( int idx ) throws IOException {
codeStream.write( GET_LOCAL );
codeStream.writeVaruint32( idx );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeStore( int idx ) throws IOException {
codeStream.write( SET_LOCAL );
codeStream.writeVaruint32( idx );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeNumericOperator( NumericOperator numOp, @Nullable ValueType valueType ) throws IOException {
int op = 0;
switch( numOp ) {
case add:
switch( valueType ) {
case i32:
op = I32_ADD;
break;
case i64:
op = I64_ADD;
break;
case f32:
op = F32_ADD;
break;
case f64:
op = F64_ADD;
break;
}
break;
case sub:
switch( valueType ) {
case i32:
op = I32_SUB;
break;
case i64:
op = I64_SUB;
break;
case f32:
op = F32_SUB;
break;
case f64:
op = F64_SUB;
break;
}
break;
case neg:
switch( valueType ) {
case f32:
op = F32_NEG;
break;
case f64:
op = F64_NEG;
break;
}
break;
case mul:
switch( valueType ) {
case i32:
op = I32_MUL;
break;
case i64:
op = I64_MUL;
break;
case f32:
op = F32_MUL;
break;
case f64:
op = F64_MUL;
break;
}
break;
case div:
switch( valueType ) {
case i32:
op = I32_DIV_S;
break;
case i64:
op = I64_DIV_S;
break;
case f32:
op = F32_DIV;
break;
case f64:
op = F64_DIV;
break;
}
break;
case rem:
switch( valueType ) {
case i32:
op = I32_REM_S;
break;
case i64:
op = I64_REM_S;
break;
}
break;
case and:
switch( valueType ) {
case i32:
op = I32_AND;
break;
case i64:
op = I64_AND;
break;
}
break;
case or:
switch( valueType ) {
case i32:
op = I32_OR;
break;
case i64:
op = I64_OR;
break;
}
break;
case xor:
switch( valueType ) {
case i32:
op = I32_XOR;
break;
case i64:
op = I64_XOR;
break;
}
break;
case shl:
switch( valueType ) {
case i32:
op = I32_SHL;
break;
case i64:
op = I64_SHL;
break;
}
break;
case shr_s:
switch( valueType ) {
case i32:
op = I32_SHR_S;
break;
case i64:
op = I64_SHR_S;
break;
}
break;
case shr_u:
switch( valueType ) {
case i32:
op = I32_SHR_U;
break;
case i64:
op = I64_SHR_U;
break;
}
break;
case eq:
switch( valueType ) {
case i32:
op = I32_EQ;
break;
case i64:
op = I64_EQ;
break;
case f32:
op = F32_EQ;
break;
case f64:
op = F64_EQ;
break;
}
break;
case ne:
switch( valueType ) {
case i32:
op = I32_NE;
break;
case i64:
op = I64_NE;
break;
case f32:
op = F32_NE;
break;
case f64:
op = F64_NE;
break;
}
break;
case gt:
switch( valueType ) {
case i32:
op = I32_GT_S;
break;
case i64:
op = I64_GT_S;
break;
case f32:
op = F32_GT;
break;
case f64:
op = F64_GT;
break;
}
break;
case lt_s:
switch( valueType ) {
case i32:
op = I32_LT_S;
break;
case i64:
op = I64_LT_S;
break;
case f32:
op = F32_LT;
break;
case f64:
op = F64_LT;
break;
}
break;
case le_s:
switch( valueType ) {
case i32:
op = I32_LE_S;
break;
case i64:
op = I64_LE_S;
break;
case f32:
op = F32_LE;
break;
case f64:
op = F64_LE;
break;
}
break;
case ge_s:
switch( valueType ) {
case i32:
op = I32_GE_S;
break;
case i64:
op = I64_GE_S;
break;
case f32:
op = F32_GE;
break;
case f64:
op = F64_GE;
break;
}
break;
}
if( op == 0 ) {
throw new Error( valueType + "." + numOp );
}
codeStream.write( op );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeCast( ValueTypeConvertion cast ) throws IOException {
int op;
switch( cast ) {
case i2l:
op = I64_EXTEND_S_I32;
break;
case i2f:
op = F32_CONVERT_S_I32;
break;
case i2d:
op = F64_CONVERT_S_I32;
break;
case l2i:
op = I32_WRAP_I64;
break;
case l2f:
op = F32_CONVERT_S_I64;
break;
case l2d:
op = F64_CONVERT_S_I64;
break;
case f2i:
op = I32_TRUNC_S_F32;
break;
case f2l:
op = I64_TRUNC_S_F32;
break;
case f2d:
op = F64_PROMOTE_F32;
break;
case d2i:
op = I32_TRUNC_S_F64;
break;
case d2l:
op = I64_TRUNC_S_F64;
break;
case d2f:
op = F32_DEMOTE_F64;
break;
default:
throw new Error( "Unknown cast: " + cast );
}
codeStream.write( op );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeFunctionCall( String name ) throws IOException {
codeStream.write( CALL );
Function func = functions.get( name );
if( func == null ) {
throw new WasmException( "Call to unknown function: " + name, null, -1 );
}
codeStream.writeVaruint32( func.id );
}
/**
* {@inheritDoc}
*/
@Override
protected void writeBlockCode( @Nonnull WasmBlockOperator op, @Nullable Object data ) throws IOException {
switch( op ) {
case RETURN:
codeStream.write( RETURN );
break;
case IF:
codeStream.write( IF );
codeStream.write( 0x40 ); // void; the return type of the block. currently we does not use it
break;
case ELSE:
codeStream.write( ELSE );
break;
case END:
codeStream.write( END );
break;
case DROP:
codeStream.write( DROP );
break;
case BLOCK:
codeStream.write( BLOCK );
codeStream.write( 0x40 ); // void; the return type of the block. currently we does not use it
break;
case BR:
codeStream.write( BR );
codeStream.writeVaruint32( (Integer)data );
break;
case BR_TABLE:
codeStream.write( BR_TABLE );
int[] targets = (int[])data;
codeStream.writeVaruint32( targets.length - 1 );
for( int i : targets ) {
codeStream.writeVaruint32( i );
}
break;
default:
throw new Error( "Unknown block: " + op );
}
}
}