src/tint/lang/hlsl/writer/ast_printer/ast_printer.h

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#ifndef SRC_TINT_LANG_HLSL_WRITER_AST_PRINTER_AST_PRINTER_H_
#define SRC_TINT_LANG_HLSL_WRITER_AST_PRINTER_AST_PRINTER_H_

#include <string>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <utility>

#include "src/tint/api/common/binding_point.h"
#include "src/tint/lang/core/builtin_value.h"
#include "src/tint/lang/hlsl/writer/ast_raise/decompose_memory_access.h"
#include "src/tint/lang/hlsl/writer/common/options.h"
#include "src/tint/lang/wgsl/program/program_builder.h"
#include "src/tint/utils/containers/scope_stack.h"
#include "src/tint/utils/generator/text_generator.h"
#include "src/tint/utils/math/hash.h"

// Forward declarations
namespace tint::sem {
class BuiltinFn;
class Call;
class ValueConstructor;
class ValueConversion;
}  // namespace tint::sem

namespace tint::hlsl::writer {

/// The result of sanitizing a program for generation.
struct SanitizedResult {
    /// Constructor
    SanitizedResult();
    /// Destructor
    ~SanitizedResult();
    /// Move constructor
    SanitizedResult(SanitizedResult&&);

    /// The sanitized program.
    Program program;
    /// Indices into the array_length_from_uniform binding that are statically
    /// used.
    std::unordered_set<uint32_t> used_array_length_from_uniform_indices;
};

/// Sanitize a program in preparation for generating HLSL.
/// @param program the input program
/// @param options The HLSL generator options.
/// @returns the sanitized program and any supplementary information
SanitizedResult Sanitize(const Program& program, const Options& options);

/// Implementation class for HLSL generator
class ASTPrinter : public tint::TextGenerator {
  public:
    /// Constructor
    /// @param program the program to generate
    explicit ASTPrinter(const Program& program);
    ~ASTPrinter() override;

    /// @returns true on successful generation; false otherwise
    bool Generate();

    /// Handles an index accessor expression
    /// @param out the output stream
    /// @param expr the expression to emit
    /// @returns true if the index accessor was emitted
    bool EmitIndexAccessor(StringStream& out, const ast::IndexAccessorExpression* expr);
    /// Handles an assignment statement
    /// @param stmt the statement to emit
    /// @returns true if the statement was emitted successfully
    bool EmitAssign(const ast::AssignmentStatement* stmt);
    /// Handles generating a binary expression
    /// @param out the output stream
    /// @param expr the binary expression
    /// @returns true if the expression was emitted, false otherwise
    bool EmitBinary(StringStream& out, const ast::BinaryExpression* expr);
    /// Handles generating a bitcast expression
    /// @param out the output stream
    /// @param expr the as expression
    /// @returns true if the bitcast was emitted
    bool EmitBitcastCall(StringStream& out, const ast::CallExpression* expr);
    /// Emits a list of statements
    /// @param stmts the statement list
    /// @returns true if the statements were emitted successfully
    bool EmitStatements(VectorRef<const ast::Statement*> stmts);
    /// Emits a list of statements with an indentation
    /// @param stmts the statement list
    /// @returns true if the statements were emitted successfully
    bool EmitStatementsWithIndent(VectorRef<const ast::Statement*> stmts);
    /// Handles a block statement
    /// @param stmt the statement to emit
    /// @returns true if the statement was emitted successfully
    bool EmitBlock(const ast::BlockStatement* stmt);
    /// Handles a break statement
    /// @param stmt the statement to emit
    /// @returns true if the statement was emitted successfully
    bool EmitBreak(const ast::BreakStatement* stmt);
    /// Handles a break-if statement
    /// @param stmt the statement to emit
    /// @returns true if the statement was emitted successfully
    bool EmitBreakIf(const ast::BreakIfStatement* stmt);
    /// Handles generating a call expression
    /// @param out the output stream
    /// @param expr the call expression
    /// @returns true if the call expression is emitted
    bool EmitCall(StringStream& out, const ast::CallExpression* expr);
    /// Handles generating a function call expression
    /// @param out the output stream
    /// @param call the call expression
    /// @param function the function being called
    /// @returns true if the expression is emitted
    bool EmitFunctionCall(StringStream& out, const sem::Call* call, const sem::Function* function);
    /// Handles generating a builtin call expression
    /// @param out the output stream
    /// @param call the call expression
    /// @param builtin the builtin being called
    /// @returns true if the expression is emitted
    bool EmitBuiltinCall(StringStream& out, const sem::Call* call, const sem::BuiltinFn* builtin);
    /// Handles generating a value conversion expression
    /// @param out the output stream
    /// @param call the call expression
    /// @param conv the value conversion
    /// @returns true if the expression is emitted
    bool EmitValueConversion(StringStream& out,
                             const sem::Call* call,
                             const sem::ValueConversion* conv);
    /// Handles generating a value constructor expression
    /// @param out the output stream
    /// @param call the call expression
    /// @param ctor the value constructor
    /// @returns true if the expression is emitted
    bool EmitValueConstructor(StringStream& out,
                              const sem::Call* call,
                              const sem::ValueConstructor* ctor);
    /// Handles generating a call expression to a
    /// DecomposeMemoryAccess::Intrinsic for a uniform buffer
    /// @param out the output stream
    /// @param expr the call expression
    /// @param intrinsic the DecomposeMemoryAccess::Intrinsic
    /// @returns true if the call expression is emitted
    bool EmitUniformBufferAccess(StringStream& out,
                                 const ast::CallExpression* expr,
                                 const DecomposeMemoryAccess::Intrinsic* intrinsic);
    /// Handles generating a call expression to a
    /// DecomposeMemoryAccess::Intrinsic for a storage buffer
    /// @param out the output stream
    /// @param expr the call expression
    /// @param intrinsic the DecomposeMemoryAccess::Intrinsic
    /// @returns true if the call expression is emitted
    bool EmitStorageBufferAccess(StringStream& out,
                                 const ast::CallExpression* expr,
                                 const DecomposeMemoryAccess::Intrinsic* intrinsic);
    /// Handles generating a barrier intrinsic call
    /// @param out the output stream
    /// @param builtin the semantic information for the barrier builtin
    /// @returns true if the call expression is emitted
    bool EmitBarrierCall(StringStream& out, const sem::BuiltinFn* builtin);
    /// Handles generating an atomic intrinsic call for a storage buffer variable
    /// @param out the output stream
    /// @param expr the call expression
    /// @param intrinsic the atomic intrinsic
    /// @returns true if the call expression is emitted
    bool EmitStorageAtomicCall(StringStream& out,
                               const ast::CallExpression* expr,
                               const DecomposeMemoryAccess::Intrinsic* intrinsic);
    /// Handles generating the helper function for the atomic intrinsic function
    /// @param func the function
    /// @param intrinsic the atomic intrinsic
    /// @returns true if the function is emitted
    bool EmitStorageAtomicIntrinsic(const ast::Function* func,
                                    const DecomposeMemoryAccess::Intrinsic* intrinsic);
    /// Handles generating an atomic intrinsic call for a workgroup variable
    /// @param out the output stream
    /// @param expr the call expression
    /// @param builtin the semantic information for the atomic builtin
    /// @returns true if the call expression is emitted
    bool EmitWorkgroupAtomicCall(StringStream& out,
                                 const ast::CallExpression* expr,
                                 const sem::BuiltinFn* builtin);
    /// Handles generating a call to a texture function (`textureSample`,
    /// `textureSampleGrad`, etc)
    /// @param out the output stream
    /// @param call the call expression
    /// @param builtin the semantic information for the texture builtin
    /// @returns true if the call expression is emitted
    bool EmitTextureCall(StringStream& out, const sem::Call* call, const sem::BuiltinFn* builtin);
    /// Handles generating a call to the `select()` builtin
    /// @param out the output stream
    /// @param expr the call expression
    /// @returns true if the call expression is emitted
    bool EmitSelectCall(StringStream& out, const ast::CallExpression* expr);
    /// Handles generating a call to the `modf()` builtin
    /// @param out the output stream
    /// @param expr the call expression
    /// @param builtin the semantic information for the builtin
    /// @returns true if the call expression is emitted
    bool EmitModfCall(StringStream& out,
                      const ast::CallExpression* expr,
                      const sem::BuiltinFn* builtin);
    /// Handles generating a call to the `frexp()` builtin
    /// @param out the output stream
    /// @param expr the call expression
    /// @param builtin the semantic information for the builtin
    /// @returns true if the call expression is emitted
    bool EmitFrexpCall(StringStream& out,
                       const ast::CallExpression* expr,
                       const sem::BuiltinFn* builtin);
    /// Handles generating a call to the `degrees()` builtin
    /// @param out the output stream
    /// @param expr the call expression
    /// @param builtin the semantic information for the builtin
    /// @returns true if the call expression is emitted
    bool EmitDegreesCall(StringStream& out,
                         const ast::CallExpression* expr,
                         const sem::BuiltinFn* builtin);
    /// Handles generating a call to the `radians()` builtin
    /// @param out the output stream
    /// @param expr the call expression
    /// @param builtin the semantic information for the builtin
    /// @returns true if the call expression is emitted
    bool EmitRadiansCall(StringStream& out,
                         const ast::CallExpression* expr,
                         const sem::BuiltinFn* builtin);
    /// Handles generating a call to the `sign()` builtin
    /// @param out the output stream
    /// @param call the call semantic node
    /// @param builtin the semantic information for the builtin
    /// @returns true if the call expression is emitted
    bool EmitSignCall(StringStream& out, const sem::Call* call, const sem::BuiltinFn* builtin);
    /// Handles generating a call to data packing builtin
    /// @param out the output stream
    /// @param expr the call expression
    /// @param builtin the semantic information for the builtin
    /// @returns true if the call expression is emitted
    bool EmitDataPackingCall(StringStream& out,
                             const ast::CallExpression* expr,
                             const sem::BuiltinFn* builtin);
    /// Handles generating a call to data unpacking builtin
    /// @param out the output stream
    /// @param expr the call expression
    /// @param builtin the semantic information for the builtin
    /// @returns true if the call expression is emitted
    bool EmitDataUnpackingCall(StringStream& out,
                               const ast::CallExpression* expr,
                               const sem::BuiltinFn* builtin);
    /// Handles generating a call to the `quantizeToF16()` intrinsic
    /// @param out the output stream
    /// @param expr the call expression
    /// @param builtin the semantic information for the builtin
    /// @returns true if the call expression is emitted
    bool EmitQuantizeToF16Call(StringStream& out,
                               const ast::CallExpression* expr,
                               const sem::BuiltinFn* builtin);
    /// Handles generating a call to the `trunc()` intrinsic
    /// @param out the output stream
    /// @param expr the call expression
    /// @param builtin the semantic information for the builtin
    /// @returns true if the call expression is emitted
    bool EmitTruncCall(StringStream& out,
                       const ast::CallExpression* expr,
                       const sem::BuiltinFn* builtin);
    /// Handles generating a call to the builtins defined in the language extension
    /// `packed_4x8_integer_dot_product`.
    /// @param out the output stream
    /// @param expr the call expression
    /// @param builtin the semantic information for the builtin
    /// @returns true if the call expression is emitted
    bool EmitPacked4x8IntegerDotProductBuiltinCall(StringStream& out,
                                                   const ast::CallExpression* expr,
                                                   const sem::BuiltinFn* builtin);
    /// Handles generating a call to the `WaveReadLaneAt` intrinsic for subgroupShuffleXor,
    /// subgroupShuffleUp and subgroupShuffleDown
    /// @param out the output stream
    /// @param expr the call expression
    /// @param builtin the semantic information for the builtin
    /// @returns true if the call expression is emitted
    bool EmitSubgroupShuffleBuiltinCall(StringStream& out,
                                        const ast::CallExpression* expr,
                                        const sem::BuiltinFn* builtin);
    /// Handles a case statement
    /// @param s the switch statement
    /// @param case_idx the index of the switch case in the switch statement
    /// @returns true if the statement was emitted successfully
    bool EmitCase(const ast::SwitchStatement* s, size_t case_idx);
    /// Handles generating a discard statement
    /// @param stmt the discard statement
    /// @returns true if the statement was successfully emitted
    bool EmitDiscard(const ast::DiscardStatement* stmt);
    /// Handles a continue statement
    /// @param stmt the statement to emit
    /// @returns true if the statement was emitted successfully
    bool EmitContinue(const ast::ContinueStatement* stmt);
    /// Handles generating an Expression
    /// @param out the output stream
    /// @param expr the expression
    /// @returns true if the expression was emitted
    bool EmitExpression(StringStream& out, const ast::Expression* expr);
    /// Handles generating an Expression for texture or storage buffer call arguments. This is
    /// specifically to work around a DXC bug around passing signed integer splatted constants as
    /// args to these functions (see crbug.com/tint/1976)
    /// @param out the output stream
    /// @param expr the expression
    /// @returns true if the expression was emitted
    bool EmitTextureOrStorageBufferCallArgExpression(StringStream& out,
                                                     const ast::Expression* expr);
    /// Handles generating a function
    /// @param func the function to generate
    /// @returns true if the function was emitted
    bool EmitFunction(const ast::Function* func);
    /// Handles emitting the function body if it discards to work around a FXC
    /// compilation bug.
    /// @param func the function with the body to emit
    /// @returns true if the function was emitted
    bool EmitFunctionBodyWithDiscard(const ast::Function* func);
    /// Handles emitting a global variable
    /// @param global the global variable
    /// @returns true on success
    bool EmitGlobalVariable(const ast::Variable* global);

    /// Handles emitting a global variable with the uniform address space
    /// @param var the AST node for the 'var'
    /// @param sem the semantic node for the 'var'
    /// @returns true on success
    bool EmitUniformVariable(const ast::Var* var, const sem::Variable* sem);

    /// Handles emitting a global variable with the storage address space
    /// @param var the AST node for the 'var'
    /// @param sem the semantic node for the 'var'
    /// @returns true on success
    bool EmitStorageVariable(const ast::Var* var, const sem::Variable* sem);

    /// Handles emitting a global variable with the handle address space
    /// @param var the AST node for the 'var'
    /// @param sem the semantic node for the 'var'
    /// @returns true on success
    bool EmitHandleVariable(const ast::Var* var, const sem::Variable* sem);

    /// Handles emitting a global variable with the private address space
    /// @param var the global variable
    /// @returns true on success
    bool EmitPrivateVariable(const sem::Variable* var);

    /// Handles emitting a global variable with the workgroup address space
    /// @param var the global variable
    /// @returns true on success
    bool EmitWorkgroupVariable(const sem::Variable* var);

    /// Handles emitting the entry point function
    /// @param func the entry point
    /// @returns true if the entry point function was emitted
    bool EmitEntryPointFunction(const ast::Function* func);
    /// Handles an if statement
    /// @param stmt the statement to emit
    /// @returns true if the statement was successfully emitted
    bool EmitIf(const ast::IfStatement* stmt);
    /// Handles a constant value
    /// @param out the output stream
    /// @param constant the constant value to emit
    /// @param is_variable_initializer true if the constant is used as the RHS of a variable
    /// initializer
    /// @returns true if the constant value was successfully emitted
    bool EmitConstant(StringStream& out,
                      const core::constant::Value* constant,
                      bool is_variable_initializer);
    /// Handles a literal
    /// @param out the output stream
    /// @param lit the literal to emit
    /// @returns true if the literal was successfully emitted
    bool EmitLiteral(StringStream& out, const ast::LiteralExpression* lit);
    /// Handles a loop statement
    /// @param stmt the statement to emit
    /// @returns true if the statement was emitted
    bool EmitLoop(const ast::LoopStatement* stmt);
    /// Handles a for loop statement
    /// @param stmt the statement to emit
    /// @returns true if the statement was emitted
    bool EmitForLoop(const ast::ForLoopStatement* stmt);
    /// Handles a while statement
    /// @param stmt the statement to emit
    /// @returns true if the statement was emitted
    bool EmitWhile(const ast::WhileStatement* stmt);
    /// Handles generating an identifier expression
    /// @param out the output stream
    /// @param expr the identifier expression
    /// @returns true if the identifeir was emitted
    bool EmitIdentifier(StringStream& out, const ast::IdentifierExpression* expr);
    /// Handles a member accessor expression
    /// @param out the output stream
    /// @param expr the member accessor expression
    /// @returns true if the member accessor was emitted
    bool EmitMemberAccessor(StringStream& out, const ast::MemberAccessorExpression* expr);
    /// Handles return statements
    /// @param stmt the statement to emit
    /// @returns true if the statement was successfully emitted
    bool EmitReturn(const ast::ReturnStatement* stmt);
    /// Handles statement
    /// @param stmt the statement to emit
    /// @returns true if the statement was emitted
    bool EmitStatement(const ast::Statement* stmt);
    /// Handles generating a switch statement
    /// @param stmt the statement to emit
    /// @returns true if the statement was emitted
    bool EmitSwitch(const ast::SwitchStatement* stmt);
    // Handles generating a switch statement with only a default case
    /// @param stmt the statement to emit
    /// @returns true if the statement was emitted
    bool EmitDefaultOnlySwitch(const ast::SwitchStatement* stmt);
    /// Handles generating type
    /// @param out the output stream
    /// @param type the type to generate
    /// @param address_space the address space of the variable
    /// @param access the access control type of the variable
    /// @param name the name of the variable, used for array emission.
    /// @param name_printed (optional) if not nullptr and an array was printed
    /// then the boolean is set to true.
    /// @returns true if the type is emitted
    bool EmitType(StringStream& out,
                  const core::type::Type* type,
                  core::AddressSpace address_space,
                  core::Access access,
                  const std::string& name,
                  bool* name_printed = nullptr);
    /// Handles generating type and name
    /// @param out the output stream
    /// @param type the type to generate
    /// @param address_space the address space of the variable
    /// @param access the access control type of the variable
    /// @param name the name to emit
    /// @returns true if the type is emitted
    bool EmitTypeAndName(StringStream& out,
                         const core::type::Type* type,
                         core::AddressSpace address_space,
                         core::Access access,
                         const std::string& name);
    /// Handles generating a structure declaration. If the structure has already been emitted, then
    /// this function will simply return `true` without emitting anything.
    /// @param buffer the text buffer that the type declaration will be written to
    /// @param ty the struct to generate
    /// @returns true if the struct is emitted
    bool EmitStructType(TextBuffer* buffer, const core::type::Struct* ty);
    /// Handles a unary op expression
    /// @param out the output stream
    /// @param expr the expression to emit
    /// @returns true if the expression was emitted
    bool EmitUnaryOp(StringStream& out, const ast::UnaryOpExpression* expr);
    /// Emits `value` for the given type
    /// @param out the output stream
    /// @param type the type to emit the value for
    /// @param value the value to emit
    /// @returns true if the value was successfully emitted.
    bool EmitValue(StringStream& out, const core::type::Type* type, int value);
    /// Emits the zero value for the given type
    /// @param out the output stream
    /// @param type the type to emit the value for
    /// @returns true if the zero value was successfully emitted.
    bool EmitZeroValue(StringStream& out, const core::type::Type* type);
    /// Handles generating a 'var' declaration
    /// @param var the variable to generate
    /// @returns true if the variable was emitted
    bool EmitVar(const ast::Var* var);
    /// Handles generating a 'let' declaration
    /// @param let the variable to generate
    /// @returns true if the variable was emitted
    bool EmitLet(const ast::Let* let);
    /// Emits call to a helper vector assignment function for the input assignment
    /// statement and vector type. This is used to work around FXC issues where
    /// assignments to vectors with dynamic indices cause compilation failures.
    /// @param stmt assignment statement that corresponds to a vector assignment
    /// via an accessor expression
    /// @param vec the vector type being assigned to
    /// @returns true on success
    bool EmitDynamicVectorAssignment(const ast::AssignmentStatement* stmt,
                                     const core::type::Vector* vec);
    /// Emits call to a helper matrix assignment function for the input assignment
    /// statement and matrix type. This is used to work around FXC issues where
    /// assignment of a vector to a matrix with a dynamic index causes compilation
    /// failures.
    /// @param stmt assignment statement that corresponds to a matrix assignment
    /// via an accessor expression
    /// @param mat the matrix type being assigned to
    /// @returns true on success
    bool EmitDynamicMatrixVectorAssignment(const ast::AssignmentStatement* stmt,
                                           const core::type::Matrix* mat);
    /// Emits call to a helper matrix assignment function for the input assignment
    /// statement and matrix type. This is used to work around FXC issues where
    /// assignment of a scalar to a matrix with at least one dynamic index causes
    /// compilation failures.
    /// @param stmt assignment statement that corresponds to a matrix assignment
    /// via an accessor expression
    /// @param mat the matrix type being assigned to
    /// @returns true on success
    bool EmitDynamicMatrixScalarAssignment(const ast::AssignmentStatement* stmt,
                                           const core::type::Matrix* mat);

    /// Handles generating a builtin method name
    /// @param builtin the semantic info for the builtin
    /// @returns the name or "" if not valid
    std::string generate_builtin_name(const sem::BuiltinFn* builtin);
    /// Converts a builtin to an attribute name
    /// @param builtin the builtin to convert
    /// @returns the string name of the builtin or blank on error
    std::string builtin_to_attribute(core::BuiltinValue builtin) const;

    /// Converts interpolation attributes to a HLSL modifiers
    /// @param type the interpolation type
    /// @param sampling the interpolation sampling
    /// @returns the string name of the attribute or blank on error
    std::string interpolation_to_modifiers(core::InterpolationType type,
                                           core::InterpolationSampling sampling) const;

  private:
    enum class VarType { kIn, kOut };

    struct EntryPointData {
        std::string struct_name;
        std::string var_name;
    };

    struct DMAIntrinsic {
        DecomposeMemoryAccess::Intrinsic::Op op;
        DecomposeMemoryAccess::Intrinsic::DataType type;
        bool operator==(const DMAIntrinsic& rhs) const { return op == rhs.op && type == rhs.type; }
        /// Hasher is a std::hash function for DMAIntrinsic
        struct Hasher {
            /// @param i the DMAIntrinsic to hash
            /// @returns the hash of `i`
            inline std::size_t operator()(const DMAIntrinsic& i) const {
                return Hash(i.op, i.type);
            }
        };
    };

    /// The map key for two semantic types.
    using BinaryType =
        tint::UnorderedKeyWrapper<std::tuple<const core::type::Type*, const core::type::Type*>>;

    /// CallBuiltinHelper will call the builtin helper function, creating it
    /// if it hasn't been built already. If the builtin needs to be built then
    /// CallBuiltinHelper will generate the function signature and will call
    /// `build` to emit the body of the function.
    /// @param out the output stream
    /// @param call the call expression
    /// @param builtin the semantic information for the builtin
    /// @param build a function with the signature:
    ///        `bool(TextBuffer* buffer, const std::vector<std::string>& params)`
    ///        Where:
    ///          `buffer` is the body of the generated function
    ///          `params` is the name of all the generated function parameters
    /// @returns true if the call expression is emitted
    template <typename F>
    bool CallBuiltinHelper(StringStream& out,
                           const ast::CallExpression* call,
                           const sem::BuiltinFn* builtin,
                           F&& build);

    /// @param s the structure
    /// @returns the name of the structure, taking special care of builtin structures that start
    /// with double underscores. If the structure is a builtin, then the returned name will be a
    /// unique name without the leading underscores.
    std::string StructName(const core::type::Struct* s);

    /// @return a new, unique identifier with the given prefix.
    /// @param prefix optional prefix to apply to the generated identifier. If empty "tint_symbol"
    /// will be used.
    std::string UniqueIdentifier(const std::string& prefix = "");

    /// Alias for builder_.TypeOf(ptr)
    template <typename T>
    auto TypeOf(T* ptr) {
        return builder_.TypeOf(ptr);
    }

    ProgramBuilder builder_;

    /// Helper functions emitted at the top of the output
    TextBuffer helpers_;

    /// Map of builtin structure to unique generated name
    std::unordered_map<const core::type::Struct*, std::string> builtin_struct_names_;
    std::function<bool()> emit_continuing_;
    std::unordered_map<const core::type::Matrix*, std::string> matrix_scalar_inits_;
    std::unordered_map<const sem::BuiltinFn*, std::string> builtins_;
    // Polyfill functions for bitcast expression, BinaryType indicates the source type and the
    // destination type.
    std::unordered_map<BinaryType, std::string> bitcast_funcs_;
    std::unordered_map<const core::type::Vector*, std::string> dynamic_vector_write_;
    std::unordered_map<const core::type::Matrix*, std::string> dynamic_matrix_vector_write_;
    std::unordered_map<const core::type::Matrix*, std::string> dynamic_matrix_scalar_write_;
    std::unordered_map<const core::type::Type*, std::string> value_or_one_if_zero_;
    std::unordered_set<const core::type::Struct*> emitted_structs_;

    // The line index in current_buffer_ of the current global declaration / function.
    size_t global_insertion_point_ = 0;
};

}  // namespace tint::hlsl::writer

#endif  // SRC_TINT_LANG_HLSL_WRITER_AST_PRINTER_AST_PRINTER_H_