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#include "src/tint/lang/spirv/reader/ast_parser/parse.h"

#include <utility>

#include "src/tint/lang/spirv/reader/ast_lower/atomics.h"
#include "src/tint/lang/spirv/reader/ast_lower/decompose_strided_array.h"
#include "src/tint/lang/spirv/reader/ast_lower/decompose_strided_matrix.h"
#include "src/tint/lang/spirv/reader/ast_lower/fold_trivial_lets.h"
#include "src/tint/lang/spirv/reader/ast_lower/pass_workgroup_id_as_argument.h"
#include "src/tint/lang/spirv/reader/ast_parser/ast_parser.h"
#include "src/tint/lang/wgsl/ast/transform/manager.h"
#include "src/tint/lang/wgsl/ast/transform/remove_unreachable_statements.h"
#include "src/tint/lang/wgsl/ast/transform/simplify_pointers.h"
#include "src/tint/lang/wgsl/ast/transform/unshadow.h"
#include "src/tint/lang/wgsl/extension.h"
#include "src/tint/lang/wgsl/program/clone_context.h"
#include "src/tint/lang/wgsl/resolver/resolve.h"

namespace tint::spirv::reader::ast_parser {

namespace {

/// Trivial transform that removes the enable directive that disables the uniformity analysis.
class ReenableUniformityAnalysis final
    : public Castable<ReenableUniformityAnalysis, ast::transform::Transform> {
  public:
    ReenableUniformityAnalysis() {}
    ~ReenableUniformityAnalysis() override {}

    /// @copydoc ast::transform::Transform::Apply
    ApplyResult Apply(const Program& src,
                      const ast::transform::DataMap&,
                      ast::transform::DataMap&) const override {
        ProgramBuilder b;
        program::CloneContext ctx = {&b, &src, /* auto_clone_symbols */ true};

        // Remove the extension that disables the uniformity analysis.
        for (auto* enable : src.AST().Enables()) {
            if (enable->HasExtension(wgsl::Extension::kChromiumDisableUniformityAnalysis) &&
                enable->extensions.Length() == 1u) {
                ctx.Remove(src.AST().GlobalDeclarations(), enable);
            }
        }

        ctx.Clone();
        return resolver::Resolve(b);
    }
};

}  // namespace

Program Parse(const std::vector<uint32_t>& input, const Options& options) {
    ASTParser parser(input);
    bool parsed = parser.Parse();

    ProgramBuilder& builder = parser.builder();
    if (!parsed) {
        // TODO(bclayton): Migrate ASTParser to using diagnostics.
        builder.Diagnostics().add_error(diag::System::Reader, parser.error());
        return Program(std::move(builder));
    }

    if (options.allow_non_uniform_derivatives) {
        // Suppress errors regarding non-uniform derivative operations if requested, by adding a
        // diagnostic directive to the module.
        builder.DiagnosticDirective(wgsl::DiagnosticSeverity::kOff, "derivative_uniformity");
    }

    // Disable the uniformity analysis temporarily.
    // We will run transforms that attempt to change the AST to satisfy the analysis.
    auto allowed_features = options.allowed_features;
    allowed_features.extensions.insert(wgsl::Extension::kChromiumDisableUniformityAnalysis);
    builder.Enable(wgsl::Extension::kChromiumDisableUniformityAnalysis);

    // The SPIR-V parser can construct disjoint AST nodes, which is invalid for
    // the Resolver. Clone the Program to clean these up.
    Program program_with_disjoint_ast(std::move(builder));

    ProgramBuilder output;
    program::CloneContext(&output, &program_with_disjoint_ast, false).Clone();
    auto program = Program(resolver::Resolve(output, allowed_features));
    if (!program.IsValid()) {
        return program;
    }

    ast::transform::Manager manager;
    ast::transform::DataMap outputs;
    manager.Add<ast::transform::Unshadow>();
    manager.Add<ast::transform::SimplifyPointers>();
    manager.Add<FoldTrivialLets>();
    manager.Add<PassWorkgroupIdAsArgument>();
    manager.Add<DecomposeStridedMatrix>();
    manager.Add<DecomposeStridedArray>();
    manager.Add<ast::transform::RemoveUnreachableStatements>();
    manager.Add<Atomics>();
    manager.Add<ReenableUniformityAnalysis>();
    return manager.Run(program, {}, outputs);
}

}  // namespace tint::spirv::reader::ast_parser

TINT_INSTANTIATE_TYPEINFO(tint::spirv::reader::ast_parser::ReenableUniformityAnalysis);