Examples with LookupSwitch com.facebook.presto.bytecode.control.LookupSwitch used on opensource projects

Example 1 with LookupSwitch

use of com.facebook.presto.bytecode.control.LookupSwitch in project presto by prestodb.

the class InCodeGenerator method generateExpression.

@Override
public BytecodeNode generateExpression(Signature signature, BytecodeGeneratorContext generatorContext, Type returnType, List<RowExpression> arguments) {
    BytecodeNode value = generatorContext.generate(arguments.get(0));
    List<RowExpression> values = arguments.subList(1, arguments.size());
    ImmutableList.Builder<BytecodeNode> valuesBytecode = ImmutableList.builder();
    for (int i = 1; i < arguments.size(); i++) {
        BytecodeNode testNode = generatorContext.generate(arguments.get(i));
        valuesBytecode.add(testNode);
    }
    Type type = arguments.get(0).getType();
    Class<?> javaType = type.getJavaType();
    SwitchGenerationCase switchGenerationCase = checkSwitchGenerationCase(type, values);
    Signature hashCodeSignature = internalOperator(HASH_CODE, BIGINT, ImmutableList.of(type));
    MethodHandle hashCodeFunction = generatorContext.getRegistry().getScalarFunctionImplementation(hashCodeSignature).getMethodHandle();
    ImmutableListMultimap.Builder<Integer, BytecodeNode> hashBucketsBuilder = ImmutableListMultimap.builder();
    ImmutableList.Builder<BytecodeNode> defaultBucket = ImmutableList.builder();
    ImmutableSet.Builder<Object> constantValuesBuilder = ImmutableSet.builder();
    for (RowExpression testValue : values) {
        BytecodeNode testBytecode = generatorContext.generate(testValue);
        if (testValue instanceof ConstantExpression && ((ConstantExpression) testValue).getValue() != null) {
            ConstantExpression constant = (ConstantExpression) testValue;
            Object object = constant.getValue();
            switch(switchGenerationCase) {
                case DIRECT_SWITCH:
                case SET_CONTAINS:
                    constantValuesBuilder.add(object);
                    break;
                case HASH_SWITCH:
                    try {
                        int hashCode = toIntExact(Long.hashCode((Long) hashCodeFunction.invoke(object)));
                        hashBucketsBuilder.put(hashCode, testBytecode);
                    } catch (Throwable throwable) {
                        throw new IllegalArgumentException("Error processing IN statement: error calculating hash code for " + object, throwable);
                    }
                    break;
                default:
                    throw new IllegalArgumentException("Not supported switch generation case: " + switchGenerationCase);
            }
        } else {
            defaultBucket.add(testBytecode);
        }
    }
    ImmutableListMultimap<Integer, BytecodeNode> hashBuckets = hashBucketsBuilder.build();
    ImmutableSet<Object> constantValues = constantValuesBuilder.build();
    LabelNode end = new LabelNode("end");
    LabelNode match = new LabelNode("match");
    LabelNode noMatch = new LabelNode("noMatch");
    LabelNode defaultLabel = new LabelNode("default");
    Scope scope = generatorContext.getScope();
    BytecodeNode switchBlock;
    BytecodeBlock switchCaseBlocks = new BytecodeBlock();
    LookupSwitch.LookupSwitchBuilder switchBuilder = lookupSwitchBuilder();
    switch(switchGenerationCase) {
        case DIRECT_SWITCH:
            // For these types, it's safe to not use presto HASH_CODE and EQUAL operator.
            for (Object constantValue : constantValues) {
                switchBuilder.addCase(toIntExact((Long) constantValue), match);
            }
            switchBuilder.defaultCase(defaultLabel);
            switchBlock = new BytecodeBlock().comment("lookupSwitch(<stackValue>))").dup(javaType).append(new IfStatement().condition(new BytecodeBlock().dup(javaType).invokeStatic(InCodeGenerator.class, "isInteger", boolean.class, long.class)).ifFalse(new BytecodeBlock().pop(javaType).gotoLabel(defaultLabel))).longToInt().append(switchBuilder.build());
            break;
        case HASH_SWITCH:
            for (Map.Entry<Integer, Collection<BytecodeNode>> bucket : hashBuckets.asMap().entrySet()) {
                LabelNode label = new LabelNode("inHash" + bucket.getKey());
                switchBuilder.addCase(bucket.getKey(), label);
                Collection<BytecodeNode> testValues = bucket.getValue();
                BytecodeBlock caseBlock = buildInCase(generatorContext, scope, type, label, match, defaultLabel, testValues, false);
                switchCaseBlocks.append(caseBlock.setDescription("case " + bucket.getKey()));
            }
            switchBuilder.defaultCase(defaultLabel);
            Binding hashCodeBinding = generatorContext.getCallSiteBinder().bind(hashCodeFunction);
            switchBlock = new BytecodeBlock().comment("lookupSwitch(hashCode(<stackValue>))").dup(javaType).append(invoke(hashCodeBinding, hashCodeSignature)).invokeStatic(Long.class, "hashCode", int.class, long.class).append(switchBuilder.build()).append(switchCaseBlocks);
            break;
        case SET_CONTAINS:
            Set<?> constantValuesSet = toFastutilHashSet(constantValues, type, registry);
            Binding constant = generatorContext.getCallSiteBinder().bind(constantValuesSet, constantValuesSet.getClass());
            switchBlock = new BytecodeBlock().comment("inListSet.contains(<stackValue>)").append(new IfStatement().condition(new BytecodeBlock().comment("value").dup(javaType).comment("set").append(loadConstant(constant)).invokeStatic(FastutilSetHelper.class, "in", boolean.class, javaType.isPrimitive() ? javaType : Object.class, constantValuesSet.getClass())).ifTrue(jump(match)));
            break;
        default:
            throw new IllegalArgumentException("Not supported switch generation case: " + switchGenerationCase);
    }
    BytecodeBlock defaultCaseBlock = buildInCase(generatorContext, scope, type, defaultLabel, match, noMatch, defaultBucket.build(), true).setDescription("default");
    BytecodeBlock block = new BytecodeBlock().comment("IN").append(value).append(ifWasNullPopAndGoto(scope, end, boolean.class, javaType)).append(switchBlock).append(defaultCaseBlock);
    BytecodeBlock matchBlock = new BytecodeBlock().setDescription("match").visitLabel(match).pop(javaType).append(generatorContext.wasNull().set(constantFalse())).push(true).gotoLabel(end);
    block.append(matchBlock);
    BytecodeBlock noMatchBlock = new BytecodeBlock().setDescription("noMatch").visitLabel(noMatch).pop(javaType).push(false).gotoLabel(end);
    block.append(noMatchBlock);
    block.visitLabel(end);
    return block;
}