Source/WebCore/Modules/webgpu/WHLSL/WHLSLComputeDimensions.cpp

/*
 * Copyright (C) 2019 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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#include "config.h"
#include "WHLSLComputeDimensions.h"

#if ENABLE(WEBGPU)

#include "WHLSLFunctionDeclaration.h"
#include "WHLSLPrepare.h"
#include "WHLSLProgram.h"
#include <wtf/Optional.h>

namespace WebCore {

namespace WHLSL {

class ComputeDimensionsVisitor : public Visitor {
public:
    ComputeDimensionsVisitor(AST::FunctionDefinition& entryPoint)
        : m_entryPoint(entryPoint)
    {
    }

    virtual ~ComputeDimensionsVisitor() = default;

    Optional<ComputeDimensions> computeDimensions() const { return m_computeDimensions; }

private:
    void visit(AST::FunctionDeclaration& functionDeclaration) override
    {
        bool foundNumThreadsFunctionAttribute = false;
        for (auto& functionAttribute : functionDeclaration.attributeBlock()) {
            auto success = WTF::visit(WTF::makeVisitor([&](AST::NumThreadsFunctionAttribute& numThreadsFunctionAttribute) {
                if (foundNumThreadsFunctionAttribute)
                    return false;
                foundNumThreadsFunctionAttribute = true;
                if (&functionDeclaration == &m_entryPoint) {
                    ASSERT(!m_computeDimensions);
                    m_computeDimensions = {{ numThreadsFunctionAttribute.width(), numThreadsFunctionAttribute.height(), numThreadsFunctionAttribute.depth() }};
                }
                return true;
            }), functionAttribute);
            if (!success) {
                setError();
                return;
            }
        }
    }

    AST::FunctionDefinition& m_entryPoint;
    Optional<ComputeDimensions> m_computeDimensions;
};

Optional<ComputeDimensions> computeDimensions(Program& program, AST::FunctionDefinition& entryPoint)
{
    ComputeDimensionsVisitor computeDimensions(entryPoint);
    computeDimensions.Visitor::visit(program);
    if (computeDimensions.error())
        return WTF::nullopt;
    return computeDimensions.computeDimensions();
}

} // namespace WHLSL

} // namespace WebCore

#endif // ENABLE(WEBGPU)