Program Listing for File spirv_glsl.hpp

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/*
 * Copyright 2015-2021 Arm Limited
 * SPDX-License-Identifier: Apache-2.0 OR MIT
 *
 * 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.
 */

/*
 * At your option, you may choose to accept this material under either:
 *  1. The Apache License, Version 2.0, found at <http://www.apache.org/licenses/LICENSE-2.0>, or
 *  2. The MIT License, found at <http://opensource.org/licenses/MIT>.
 */

#ifndef SPIRV_CROSS_GLSL_HPP
#define SPIRV_CROSS_GLSL_HPP

#include "GLSL.std.450.h"
#include "spirv_cross.hpp"
#include <unordered_map>
#include <unordered_set>
#include <utility>

namespace SPIRV_CROSS_NAMESPACE
{
enum PlsFormat
{
    PlsNone = 0,

    PlsR11FG11FB10F,
    PlsR32F,
    PlsRG16F,
    PlsRGB10A2,
    PlsRGBA8,
    PlsRG16,

    PlsRGBA8I,
    PlsRG16I,

    PlsRGB10A2UI,
    PlsRGBA8UI,
    PlsRG16UI,
    PlsR32UI
};

struct PlsRemap
{
    uint32_t id;
    PlsFormat format;
};

enum AccessChainFlagBits
{
    ACCESS_CHAIN_INDEX_IS_LITERAL_BIT = 1 << 0,
    ACCESS_CHAIN_CHAIN_ONLY_BIT = 1 << 1,
    ACCESS_CHAIN_PTR_CHAIN_BIT = 1 << 2,
    ACCESS_CHAIN_SKIP_REGISTER_EXPRESSION_READ_BIT = 1 << 3,
    ACCESS_CHAIN_LITERAL_MSB_FORCE_ID = 1 << 4,
    ACCESS_CHAIN_FLATTEN_ALL_MEMBERS_BIT = 1 << 5,
    ACCESS_CHAIN_FORCE_COMPOSITE_BIT = 1 << 6,
    ACCESS_CHAIN_PTR_CHAIN_POINTER_ARITH_BIT = 1 << 7,
    ACCESS_CHAIN_PTR_CHAIN_CAST_TO_SCALAR_BIT = 1 << 8
};
typedef uint32_t AccessChainFlags;

class CompilerGLSL : public Compiler
{
public:
    struct Options
    {
        // The shading language version. Corresponds to #version $VALUE.
        uint32_t version = 450;

        // Emit the OpenGL ES shading language instead of desktop OpenGL.
        bool es = false;

        // Debug option to always emit temporary variables for all expressions.
        bool force_temporary = false;
        // Debug option, can be increased in an attempt to workaround SPIRV-Cross bugs temporarily.
        // If this limit has to be increased, it points to an implementation bug.
        // In certain scenarios, the maximum number of debug iterations may increase beyond this limit
        // as long as we can prove we're making certain kinds of forward progress.
        uint32_t force_recompile_max_debug_iterations = 3;

        // If true, Vulkan GLSL features are used instead of GL-compatible features.
        // Mostly useful for debugging SPIR-V files.
        bool vulkan_semantics = false;

        // If true, gl_PerVertex is explicitly redeclared in vertex, geometry and tessellation shaders.
        // The members of gl_PerVertex is determined by which built-ins are declared by the shader.
        // This option is ignored in ES versions, as redeclaration in ES is not required, and it depends on a different extension
        // (EXT_shader_io_blocks) which makes things a bit more fuzzy.
        bool separate_shader_objects = false;

        // Flattens multidimensional arrays, e.g. float foo[a][b][c] into single-dimensional arrays,
        // e.g. float foo[a * b * c].
        // This function does not change the actual SPIRType of any object.
        // Only the generated code, including declarations of interface variables are changed to be single array dimension.
        bool flatten_multidimensional_arrays = false;

        // For older desktop GLSL targets than version 420, the
        // GL_ARB_shading_language_420pack extensions is used to be able to support
        // layout(binding) on UBOs and samplers.
        // If disabled on older targets, binding decorations will be stripped.
        bool enable_420pack_extension = true;

        // In non-Vulkan GLSL, emit push constant blocks as UBOs rather than plain uniforms.
        bool emit_push_constant_as_uniform_buffer = false;

        // Always emit uniform blocks as plain uniforms, regardless of the GLSL version, even when UBOs are supported.
        // Does not apply to shader storage or push constant blocks.
        bool emit_uniform_buffer_as_plain_uniforms = false;

        // Emit OpLine directives if present in the module.
        // May not correspond exactly to original source, but should be a good approximation.
        bool emit_line_directives = false;

        // In cases where readonly/writeonly decoration are not used at all,
        // we try to deduce which qualifier(s) we should actually used, since actually emitting
        // read-write decoration is very rare, and older glslang/HLSL compilers tend to just emit readwrite as a matter of fact.
        // The default (true) is to enable automatic deduction for these cases, but if you trust the decorations set
        // by the SPIR-V, it's recommended to set this to false.
        bool enable_storage_image_qualifier_deduction = true;

        // On some targets (WebGPU), uninitialized variables are banned.
        // If this is enabled, all variables (temporaries, Private, Function)
        // which would otherwise be uninitialized will now be initialized to 0 instead.
        bool force_zero_initialized_variables = false;

        // In GLSL, force use of I/O block flattening, similar to
        // what happens on legacy GLSL targets for blocks and structs.
        bool force_flattened_io_blocks = false;

        // For opcodes where we have to perform explicit additional nan checks, very ugly code is generated.
        // If we opt-in, ignore these requirements.
        // In opcodes like NClamp/NMin/NMax and FP compare, ignore NaN behavior.
        // Use FClamp/FMin/FMax semantics for clamps and lets implementation choose ordered or unordered
        // compares.
        bool relax_nan_checks = false;

        // Loading row-major matrices from UBOs on older AMD Windows OpenGL drivers is problematic.
        // To load these types correctly, we must generate a wrapper. them in a dummy function which only purpose is to
        // ensure row_major decoration is actually respected.
        // This workaround may cause significant performance degeneration on some Android devices.
        bool enable_row_major_load_workaround = true;

        // If non-zero, controls layout(num_views = N) in; in GL_OVR_multiview2.
        uint32_t ovr_multiview_view_count = 0;

        enum Precision
        {
            DontCare,
            Lowp,
            Mediump,
            Highp
        };

        struct VertexOptions
        {
            // "Vertex-like shader" here is any shader stage that can write BuiltInPosition.

            // GLSL: In vertex-like shaders, rewrite [0, w] depth (Vulkan/D3D style) to [-w, w] depth (GL style).
            // MSL: In vertex-like shaders, rewrite [-w, w] depth (GL style) to [0, w] depth.
            // HLSL: In vertex-like shaders, rewrite [-w, w] depth (GL style) to [0, w] depth.
            bool fixup_clipspace = false;

            // In vertex-like shaders, inverts gl_Position.y or equivalent.
            bool flip_vert_y = false;

            // GLSL only, for HLSL version of this option, see CompilerHLSL.
            // If true, the backend will assume that InstanceIndex will need to apply
            // a base instance offset. Set to false if you know you will never use base instance
            // functionality as it might remove some internal uniforms.
            bool support_nonzero_base_instance = true;
        } vertex;

        struct FragmentOptions
        {
            // Add precision mediump float in ES targets when emitting GLES source.
            // Add precision highp int in ES targets when emitting GLES source.
            Precision default_float_precision = Mediump;
            Precision default_int_precision = Highp;
        } fragment;
    };

    void remap_pixel_local_storage(std::vector<PlsRemap> inputs, std::vector<PlsRemap> outputs)
    {
        pls_inputs = std::move(inputs);
        pls_outputs = std::move(outputs);
        remap_pls_variables();
    }

    // Redirect a subpassInput reading from input_attachment_index to instead load its value from
    // the color attachment at location = color_location. Requires ESSL.
    // If coherent, uses GL_EXT_shader_framebuffer_fetch, if not, uses noncoherent variant.
    void remap_ext_framebuffer_fetch(uint32_t input_attachment_index, uint32_t color_location, bool coherent);

    explicit CompilerGLSL(std::vector<uint32_t> spirv_)
        : Compiler(std::move(spirv_))
    {
        init();
    }

    CompilerGLSL(const uint32_t *ir_, size_t word_count)
        : Compiler(ir_, word_count)
    {
        init();
    }

    explicit CompilerGLSL(const ParsedIR &ir_)
        : Compiler(ir_)
    {
        init();
    }

    explicit CompilerGLSL(ParsedIR &&ir_)
        : Compiler(std::move(ir_))
    {
        init();
    }

    const Options &get_common_options() const
    {
        return options;
    }

    void set_common_options(const Options &opts)
    {
        options = opts;
    }

    std::string compile() override;

    // Returns the current string held in the conversion buffer. Useful for
    // capturing what has been converted so far when compile() throws an error.
    std::string get_partial_source();

    // Adds a line to be added right after #version in GLSL backend.
    // This is useful for enabling custom extensions which are outside the scope of SPIRV-Cross.
    // This can be combined with variable remapping.
    // A new-line will be added.
    //
    // While add_header_line() is a more generic way of adding arbitrary text to the header
    // of a GLSL file, require_extension() should be used when adding extensions since it will
    // avoid creating collisions with SPIRV-Cross generated extensions.
    //
    // Code added via add_header_line() is typically backend-specific.
    void add_header_line(const std::string &str);

    // Adds an extension which is required to run this shader, e.g.
    // require_extension("GL_KHR_my_extension");
    void require_extension(const std::string &ext);

    // Returns the list of required extensions. After compilation this will contains any other
    // extensions that the compiler used automatically, in addition to the user specified ones.
    const SmallVector<std::string> &get_required_extensions() const;

    // Legacy GLSL compatibility method.
    // Takes a uniform or push constant variable and flattens it into a (i|u)vec4 array[N]; array instead.
    // For this to work, all types in the block must be the same basic type, e.g. mixing vec2 and vec4 is fine, but
    // mixing int and float is not.
    // The name of the uniform array will be the same as the interface block name.
    void flatten_buffer_block(VariableID id);

    // After compilation, query if a variable ID was used as a depth resource.
    // This is meaningful for MSL since descriptor types depend on this knowledge.
    // Cases which return true:
    // - Images which are declared with depth = 1 image type.
    // - Samplers which are statically used at least once with Dref opcodes.
    // - Images which are statically used at least once with Dref opcodes.
    bool variable_is_depth_or_compare(VariableID id) const;

    // If a shader output is active in this stage, but inactive in a subsequent stage,
    // this can be signalled here. This can be used to work around certain cross-stage matching problems
    // which plagues MSL and HLSL in certain scenarios.
    // An output which matches one of these will not be emitted in stage output interfaces, but rather treated as a private
    // variable.
    // This option is only meaningful for MSL and HLSL, since GLSL matches by location directly.
    // Masking builtins only takes effect if the builtin in question is part of the stage output interface.
    void mask_stage_output_by_location(uint32_t location, uint32_t component);
    void mask_stage_output_by_builtin(spv::BuiltIn builtin);

    // Allow to control how to format float literals in the output.
    // Set to "nullptr" to use the default "convert_to_string" function.
    // This handle is not owned by SPIRV-Cross and must remain valid until compile() has been called.
    void set_float_formatter(FloatFormatter *formatter)
    {
        float_formatter = formatter;
    }

protected:
    struct ShaderSubgroupSupportHelper
    {
        // lower enum value = greater priority
        enum Candidate
        {
            KHR_shader_subgroup_ballot,
            KHR_shader_subgroup_basic,
            KHR_shader_subgroup_vote,
            KHR_shader_subgroup_arithmetic,
            NV_gpu_shader_5,
            NV_shader_thread_group,
            NV_shader_thread_shuffle,
            ARB_shader_ballot,
            ARB_shader_group_vote,
            AMD_gcn_shader,

            CandidateCount
        };

        static const char *get_extension_name(Candidate c);
        static SmallVector<std::string> get_extra_required_extension_names(Candidate c);
        static const char *get_extra_required_extension_predicate(Candidate c);

        enum Feature
        {
            SubgroupMask = 0,
            SubgroupSize = 1,
            SubgroupInvocationID = 2,
            SubgroupID = 3,
            NumSubgroups = 4,
            SubgroupBroadcast_First = 5,
            SubgroupBallotFindLSB_MSB = 6,
            SubgroupAll_Any_AllEqualBool = 7,
            SubgroupAllEqualT = 8,
            SubgroupElect = 9,
            SubgroupBarrier = 10,
            SubgroupMemBarrier = 11,
            SubgroupBallot = 12,
            SubgroupInverseBallot_InclBitCount_ExclBitCout = 13,
            SubgroupBallotBitExtract = 14,
            SubgroupBallotBitCount = 15,
            SubgroupArithmeticIAddReduce = 16,
            SubgroupArithmeticIAddExclusiveScan = 17,
            SubgroupArithmeticIAddInclusiveScan = 18,
            SubgroupArithmeticFAddReduce = 19,
            SubgroupArithmeticFAddExclusiveScan = 20,
            SubgroupArithmeticFAddInclusiveScan = 21,
            SubgroupArithmeticIMulReduce = 22,
            SubgroupArithmeticIMulExclusiveScan = 23,
            SubgroupArithmeticIMulInclusiveScan = 24,
            SubgroupArithmeticFMulReduce = 25,
            SubgroupArithmeticFMulExclusiveScan = 26,
            SubgroupArithmeticFMulInclusiveScan = 27,
            FeatureCount
        };

        using FeatureMask = uint32_t;
        static_assert(sizeof(FeatureMask) * 8u >= FeatureCount, "Mask type needs more bits.");

        using CandidateVector = SmallVector<Candidate, CandidateCount>;
        using FeatureVector = SmallVector<Feature>;

        static FeatureVector get_feature_dependencies(Feature feature);
        static FeatureMask get_feature_dependency_mask(Feature feature);
        static bool can_feature_be_implemented_without_extensions(Feature feature);
        static Candidate get_KHR_extension_for_feature(Feature feature);

        struct Result
        {
            Result();
            uint32_t weights[CandidateCount];
        };

        void request_feature(Feature feature);
        bool is_feature_requested(Feature feature) const;
        Result resolve() const;

        static CandidateVector get_candidates_for_feature(Feature ft, const Result &r);

    private:
        static CandidateVector get_candidates_for_feature(Feature ft);
        static FeatureMask build_mask(const SmallVector<Feature> &features);
        FeatureMask feature_mask = 0;
    };

    // TODO remove this function when all subgroup ops are supported (or make it always return true)
    static bool is_supported_subgroup_op_in_opengl(spv::Op op, const uint32_t *ops);

    void reset(uint32_t iteration_count);
    void emit_function(SPIRFunction &func, const Bitset &return_flags);

    bool has_extension(const std::string &ext) const;
    void require_extension_internal(const std::string &ext);

    // Virtualize methods which need to be overridden by subclass targets like C++ and such.
    virtual void emit_function_prototype(SPIRFunction &func, const Bitset &return_flags);

    SPIRBlock *current_emitting_block = nullptr;
    SmallVector<SPIRBlock *> current_emitting_switch_stack;
    bool current_emitting_switch_fallthrough = false;

    virtual void emit_instruction(const Instruction &instr);
    struct TemporaryCopy
    {
        uint32_t dst_id;
        uint32_t src_id;
    };
    TemporaryCopy handle_instruction_precision(const Instruction &instr);
    void emit_block_instructions(SPIRBlock &block);
    void emit_block_instructions_with_masked_debug(SPIRBlock &block);

    // For relax_nan_checks.
    GLSLstd450 get_remapped_glsl_op(GLSLstd450 std450_op) const;
    spv::Op get_remapped_spirv_op(spv::Op op) const;

    virtual void emit_glsl_op(uint32_t result_type, uint32_t result_id, uint32_t op, const uint32_t *args,
                              uint32_t count);
    virtual void emit_spv_amd_shader_ballot_op(uint32_t result_type, uint32_t result_id, uint32_t op,
                                               const uint32_t *args, uint32_t count);
    virtual void emit_spv_amd_shader_explicit_vertex_parameter_op(uint32_t result_type, uint32_t result_id, uint32_t op,
                                                                  const uint32_t *args, uint32_t count);
    virtual void emit_spv_amd_shader_trinary_minmax_op(uint32_t result_type, uint32_t result_id, uint32_t op,
                                                       const uint32_t *args, uint32_t count);
    virtual void emit_spv_amd_gcn_shader_op(uint32_t result_type, uint32_t result_id, uint32_t op, const uint32_t *args,
                                            uint32_t count);
    virtual void emit_header();
    void emit_line_directive(uint32_t file_id, uint32_t line_literal);
    void build_workgroup_size(SmallVector<std::string> &arguments, const SpecializationConstant &x,
                              const SpecializationConstant &y, const SpecializationConstant &z);

    void request_subgroup_feature(ShaderSubgroupSupportHelper::Feature feature);

    virtual void emit_sampled_image_op(uint32_t result_type, uint32_t result_id, uint32_t image_id, uint32_t samp_id);
    virtual void emit_texture_op(const Instruction &i, bool sparse);
    virtual std::string to_texture_op(const Instruction &i, bool sparse, bool *forward,
                                      SmallVector<uint32_t> &inherited_expressions);
    virtual void emit_subgroup_op(const Instruction &i);
    virtual std::string type_to_glsl(const SPIRType &type, uint32_t id = 0);
    virtual std::string builtin_to_glsl(spv::BuiltIn builtin, spv::StorageClass storage);
    virtual void emit_struct_member(const SPIRType &type, uint32_t member_type_id, uint32_t index,
                                    const std::string &qualifier = "", uint32_t base_offset = 0);
    virtual void emit_struct_padding_target(const SPIRType &type);
    virtual std::string image_type_glsl(const SPIRType &type, uint32_t id = 0, bool member = false);
    std::string constant_expression(const SPIRConstant &c,
                                    bool inside_block_like_struct_scope = false,
                                    bool inside_struct_scope = false);
    virtual std::string constant_op_expression(const SPIRConstantOp &cop);
    virtual std::string constant_expression_vector(const SPIRConstant &c, uint32_t vector);
    virtual void emit_fixup();
    virtual std::string variable_decl(const SPIRType &type, const std::string &name, uint32_t id = 0);
    virtual bool variable_decl_is_remapped_storage(const SPIRVariable &var, spv::StorageClass storage) const;
    virtual std::string to_func_call_arg(const SPIRFunction::Parameter &arg, uint32_t id);

    struct TextureFunctionBaseArguments
    {
        // GCC 4.8 workarounds, it doesn't understand '{}' constructor here, use explicit default constructor.
        TextureFunctionBaseArguments() = default;
        VariableID img = 0;
        const SPIRType *imgtype = nullptr;
        bool is_fetch = false, is_gather = false, is_proj = false;
    };

    struct TextureFunctionNameArguments
    {
        // GCC 4.8 workarounds, it doesn't understand '{}' constructor here, use explicit default constructor.
        TextureFunctionNameArguments() = default;
        TextureFunctionBaseArguments base;
        bool has_array_offsets = false, has_offset = false, has_grad = false;
        bool has_dref = false, is_sparse_feedback = false, has_min_lod = false;
        uint32_t lod = 0;
    };
    virtual std::string to_function_name(const TextureFunctionNameArguments &args);

    struct TextureFunctionArguments
    {
        // GCC 4.8 workarounds, it doesn't understand '{}' constructor here, use explicit default constructor.
        TextureFunctionArguments() = default;
        TextureFunctionBaseArguments base;
        uint32_t coord = 0, coord_components = 0, dref = 0;
        uint32_t grad_x = 0, grad_y = 0, lod = 0, offset = 0;
        uint32_t bias = 0, component = 0, sample = 0, sparse_texel = 0, min_lod = 0;
        bool nonuniform_expression = false, has_array_offsets = false;
    };
    virtual std::string to_function_args(const TextureFunctionArguments &args, bool *p_forward);

    void emit_sparse_feedback_temporaries(uint32_t result_type_id, uint32_t id, uint32_t &feedback_id,
                                          uint32_t &texel_id);
    uint32_t get_sparse_feedback_texel_id(uint32_t id) const;
    virtual void emit_buffer_block(const SPIRVariable &type);
    virtual void emit_push_constant_block(const SPIRVariable &var);
    virtual void emit_uniform(const SPIRVariable &var);
    virtual std::string unpack_expression_type(std::string expr_str, const SPIRType &type, uint32_t physical_type_id,
                                               bool packed_type, bool row_major);

    virtual bool builtin_translates_to_nonarray(spv::BuiltIn builtin) const;

    virtual bool is_user_type_structured(uint32_t id) const;

    void emit_copy_logical_type(uint32_t lhs_id, uint32_t lhs_type_id, uint32_t rhs_id, uint32_t rhs_type_id,
                                SmallVector<uint32_t> chain);

    StringStream<> buffer;

    template <typename T>
    inline void statement_inner(T &&t)
    {
        buffer << std::forward<T>(t);
        statement_count++;
    }

    template <typename T, typename... Ts>
    inline void statement_inner(T &&t, Ts &&... ts)
    {
        buffer << std::forward<T>(t);
        statement_count++;
        statement_inner(std::forward<Ts>(ts)...);
    }

    template <typename... Ts>
    inline void statement(Ts &&... ts)
    {
        if (is_forcing_recompilation())
        {
            // Do not bother emitting code while force_recompile is active.
            // We will compile again.
            statement_count++;
            return;
        }

        if (redirect_statement)
        {
            redirect_statement->push_back(join(std::forward<Ts>(ts)...));
            statement_count++;
        }
        else
        {
            for (uint32_t i = 0; i < indent; i++)
                buffer << "    ";
            statement_inner(std::forward<Ts>(ts)...);
            buffer << '\n';
        }
    }

    template <typename... Ts>
    inline void statement_no_indent(Ts &&... ts)
    {
        auto old_indent = indent;
        indent = 0;
        statement(std::forward<Ts>(ts)...);
        indent = old_indent;
    }

    // Used for implementing continue blocks where
    // we want to obtain a list of statements we can merge
    // on a single line separated by comma.
    SmallVector<std::string> *redirect_statement = nullptr;
    const SPIRBlock *current_continue_block = nullptr;
    bool block_temporary_hoisting = false;
    bool block_debug_directives = false;

    void begin_scope();
    void end_scope();
    void end_scope(const std::string &trailer);
    void end_scope_decl();
    void end_scope_decl(const std::string &decl);

    Options options;

    // Allow Metal to use the array<T> template to make arrays a value type
    virtual std::string type_to_array_glsl(const SPIRType &type, uint32_t variable_id);
    std::string to_array_size(const SPIRType &type, uint32_t index);
    uint32_t to_array_size_literal(const SPIRType &type, uint32_t index) const;
    uint32_t to_array_size_literal(const SPIRType &type) const;
    virtual std::string variable_decl(const SPIRVariable &variable); // Threadgroup arrays can't have a wrapper type
    std::string variable_decl_function_local(SPIRVariable &variable);

    void add_local_variable_name(uint32_t id);
    void add_resource_name(uint32_t id);
    void add_member_name(SPIRType &type, uint32_t name);
    void add_function_overload(const SPIRFunction &func);

    virtual bool is_non_native_row_major_matrix(uint32_t id);
    virtual bool member_is_non_native_row_major_matrix(const SPIRType &type, uint32_t index);
    bool member_is_remapped_physical_type(const SPIRType &type, uint32_t index) const;
    bool member_is_packed_physical_type(const SPIRType &type, uint32_t index) const;
    virtual std::string convert_row_major_matrix(std::string exp_str, const SPIRType &exp_type,
                                                 uint32_t physical_type_id, bool is_packed,
                                                 bool relaxed = false);

    std::unordered_set<std::string> local_variable_names;
    std::unordered_set<std::string> resource_names;
    std::unordered_set<std::string> block_input_names;
    std::unordered_set<std::string> block_output_names;
    std::unordered_set<std::string> block_ubo_names;
    std::unordered_set<std::string> block_ssbo_names;
    std::unordered_set<std::string> block_names; // A union of all block_*_names.
    std::unordered_map<std::string, std::unordered_set<uint64_t>> function_overloads;
    std::unordered_map<uint32_t, std::string> preserved_aliases;
    void preserve_alias_on_reset(uint32_t id);
    void reset_name_caches();

    bool processing_entry_point = false;

    // Can be overriden by subclass backends for trivial things which
    // shouldn't need polymorphism.
    struct BackendVariations
    {
        std::string discard_literal = "discard";
        std::string demote_literal = "demote";
        std::string null_pointer_literal = "";
        bool float_literal_suffix = false;
        bool double_literal_suffix = true;
        bool uint32_t_literal_suffix = true;
        bool long_long_literal_suffix = false;
        const char *basic_int_type = "int";
        const char *basic_uint_type = "uint";
        const char *basic_int8_type = "int8_t";
        const char *basic_uint8_type = "uint8_t";
        const char *basic_int16_type = "int16_t";
        const char *basic_uint16_type = "uint16_t";
        const char *int16_t_literal_suffix = "s";
        const char *uint16_t_literal_suffix = "us";
        const char *nonuniform_qualifier = "nonuniformEXT";
        const char *boolean_mix_function = "mix";
        SPIRType::BaseType boolean_in_struct_remapped_type = SPIRType::Boolean;
        bool swizzle_is_function = false;
        bool shared_is_implied = false;
        bool unsized_array_supported = true;
        bool explicit_struct_type = false;
        bool use_initializer_list = false;
        bool use_typed_initializer_list = false;
        bool can_declare_struct_inline = true;
        bool can_declare_arrays_inline = true;
        bool native_row_major_matrix = true;
        bool use_constructor_splatting = true;
        bool allow_precision_qualifiers = false;
        bool can_swizzle_scalar = false;
        bool force_gl_in_out_block = false;
        bool force_merged_mesh_block = false;
        bool can_return_array = true;
        bool allow_truncated_access_chain = false;
        bool supports_extensions = false;
        bool supports_empty_struct = false;
        bool array_is_value_type = true;
        bool array_is_value_type_in_buffer_blocks = true;
        bool comparison_image_samples_scalar = false;
        bool native_pointers = false;
        bool support_small_type_sampling_result = false;
        bool support_case_fallthrough = true;
        bool use_array_constructor = false;
        bool needs_row_major_load_workaround = false;
        bool support_pointer_to_pointer = false;
        bool support_precise_qualifier = false;
        bool support_64bit_switch = false;
        bool workgroup_size_is_hidden = false;
        bool requires_relaxed_precision_analysis = false;
        bool implicit_c_integer_promotion_rules = false;
    } backend;

    void emit_struct(SPIRType &type);
    void emit_resources();
    void emit_extension_workarounds(spv::ExecutionModel model);
    void emit_subgroup_arithmetic_workaround(const std::string &func, spv::Op op, spv::GroupOperation group_op);
    void emit_polyfills(uint32_t polyfills, bool relaxed);
    void emit_buffer_block_native(const SPIRVariable &var);
    void emit_buffer_reference_block(uint32_t type_id, bool forward_declaration);
    void emit_buffer_block_legacy(const SPIRVariable &var);
    void emit_buffer_block_flattened(const SPIRVariable &type);
    void fixup_implicit_builtin_block_names(spv::ExecutionModel model);
    void emit_declared_builtin_block(spv::StorageClass storage, spv::ExecutionModel model);
    bool should_force_emit_builtin_block(spv::StorageClass storage);
    void emit_push_constant_block_vulkan(const SPIRVariable &var);
    void emit_push_constant_block_glsl(const SPIRVariable &var);
    void emit_interface_block(const SPIRVariable &type);
    void emit_flattened_io_block(const SPIRVariable &var, const char *qual);
    void emit_flattened_io_block_struct(const std::string &basename, const SPIRType &type, const char *qual,
                                        const SmallVector<uint32_t> &indices);
    void emit_flattened_io_block_member(const std::string &basename, const SPIRType &type, const char *qual,
                                        const SmallVector<uint32_t> &indices);
    void emit_block_chain(SPIRBlock &block);
    void emit_hoisted_temporaries(SmallVector<std::pair<TypeID, ID>> &temporaries);
    std::string constant_value_macro_name(uint32_t id);
    int get_constant_mapping_to_workgroup_component(const SPIRConstant &constant) const;
    void emit_constant(const SPIRConstant &constant);
    void emit_specialization_constant_op(const SPIRConstantOp &constant);
    std::string emit_continue_block(uint32_t continue_block, bool follow_true_block, bool follow_false_block);
    bool attempt_emit_loop_header(SPIRBlock &block, SPIRBlock::Method method);

    void branch(BlockID from, BlockID to);
    void branch_to_continue(BlockID from, BlockID to);
    void branch(BlockID from, uint32_t cond, BlockID true_block, BlockID false_block);
    void flush_phi(BlockID from, BlockID to);
    void flush_variable_declaration(uint32_t id);
    void flush_undeclared_variables(SPIRBlock &block);
    void emit_variable_temporary_copies(const SPIRVariable &var);

    bool should_dereference(uint32_t id);
    bool should_forward(uint32_t id) const;
    bool should_suppress_usage_tracking(uint32_t id) const;
    void emit_mix_op(uint32_t result_type, uint32_t id, uint32_t left, uint32_t right, uint32_t lerp);
    void emit_nminmax_op(uint32_t result_type, uint32_t id, uint32_t op0, uint32_t op1, GLSLstd450 op);
    void emit_emulated_ahyper_op(uint32_t result_type, uint32_t result_id, uint32_t op0, GLSLstd450 op);
    bool to_trivial_mix_op(const SPIRType &type, std::string &op, uint32_t left, uint32_t right, uint32_t lerp);
    void emit_quaternary_func_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, uint32_t op2,
                                 uint32_t op3, const char *op);
    void emit_trinary_func_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, uint32_t op2,
                              const char *op);
    void emit_binary_func_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, const char *op);
    void emit_atomic_func_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, const char *op);
    void emit_atomic_func_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, uint32_t op2, const char *op);

    void emit_unary_func_op_cast(uint32_t result_type, uint32_t result_id, uint32_t op0, const char *op,
                                 SPIRType::BaseType input_type, SPIRType::BaseType expected_result_type);
    void emit_binary_func_op_cast(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, const char *op,
                                  SPIRType::BaseType input_type, bool skip_cast_if_equal_type);
    void emit_binary_func_op_cast_clustered(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
                                            const char *op, SPIRType::BaseType input_type);
    void emit_trinary_func_op_cast(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, uint32_t op2,
                                   const char *op, SPIRType::BaseType input_type);
    void emit_trinary_func_op_bitextract(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
                                         uint32_t op2, const char *op, SPIRType::BaseType expected_result_type,
                                         SPIRType::BaseType input_type0, SPIRType::BaseType input_type1,
                                         SPIRType::BaseType input_type2);
    void emit_bitfield_insert_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, uint32_t op2,
                                 uint32_t op3, const char *op, SPIRType::BaseType offset_count_type);

    void emit_unary_func_op(uint32_t result_type, uint32_t result_id, uint32_t op0, const char *op);
    void emit_unrolled_unary_op(uint32_t result_type, uint32_t result_id, uint32_t operand, const char *op);
    void emit_binary_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, const char *op);
    void emit_unrolled_binary_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, const char *op,
                                 bool negate, SPIRType::BaseType expected_type);
    void emit_binary_op_cast(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, const char *op,
                             SPIRType::BaseType input_type, bool skip_cast_if_equal_type, bool implicit_integer_promotion);

    SPIRType binary_op_bitcast_helper(std::string &cast_op0, std::string &cast_op1, SPIRType::BaseType &input_type,
                                      uint32_t op0, uint32_t op1, bool skip_cast_if_equal_type);

    virtual bool emit_complex_bitcast(uint32_t result_type, uint32_t id, uint32_t op0);

    std::string to_ternary_expression(const SPIRType &result_type, uint32_t select, uint32_t true_value,
                                      uint32_t false_value);

    void emit_unary_op(uint32_t result_type, uint32_t result_id, uint32_t op0, const char *op);
    void emit_unary_op_cast(uint32_t result_type, uint32_t result_id, uint32_t op0, const char *op);
    virtual void emit_mesh_tasks(SPIRBlock &block);
    bool expression_is_forwarded(uint32_t id) const;
    bool expression_suppresses_usage_tracking(uint32_t id) const;
    bool expression_read_implies_multiple_reads(uint32_t id) const;
    SPIRExpression &emit_op(uint32_t result_type, uint32_t result_id, const std::string &rhs, bool forward_rhs,
                            bool suppress_usage_tracking = false);

    void access_chain_internal_append_index(std::string &expr, uint32_t base, const SPIRType *type,
                                            AccessChainFlags flags, bool &access_chain_is_arrayed, uint32_t index);

    std::string access_chain_internal(uint32_t base, const uint32_t *indices, uint32_t count, AccessChainFlags flags,
                                      AccessChainMeta *meta);

    // Only meaningful on backends with physical pointer support ala MSL.
    // Relevant for PtrAccessChain / BDA.
    virtual uint32_t get_physical_type_stride(const SPIRType &type) const;

    spv::StorageClass get_expression_effective_storage_class(uint32_t ptr);
    virtual bool access_chain_needs_stage_io_builtin_translation(uint32_t base);

    virtual void check_physical_type_cast(std::string &expr, const SPIRType *type, uint32_t physical_type);
    virtual bool prepare_access_chain_for_scalar_access(std::string &expr, const SPIRType &type,
                                                        spv::StorageClass storage, bool &is_packed);

    std::string access_chain(uint32_t base, const uint32_t *indices, uint32_t count, const SPIRType &target_type,
                             AccessChainMeta *meta = nullptr, bool ptr_chain = false);

    std::string flattened_access_chain(uint32_t base, const uint32_t *indices, uint32_t count,
                                       const SPIRType &target_type, uint32_t offset, uint32_t matrix_stride,
                                       uint32_t array_stride, bool need_transpose);
    std::string flattened_access_chain_struct(uint32_t base, const uint32_t *indices, uint32_t count,
                                              const SPIRType &target_type, uint32_t offset);
    std::string flattened_access_chain_matrix(uint32_t base, const uint32_t *indices, uint32_t count,
                                              const SPIRType &target_type, uint32_t offset, uint32_t matrix_stride,
                                              bool need_transpose);
    std::string flattened_access_chain_vector(uint32_t base, const uint32_t *indices, uint32_t count,
                                              const SPIRType &target_type, uint32_t offset, uint32_t matrix_stride,
                                              bool need_transpose);
    std::pair<std::string, uint32_t> flattened_access_chain_offset(const SPIRType &basetype, const uint32_t *indices,
                                                                   uint32_t count, uint32_t offset,
                                                                   uint32_t word_stride, bool *need_transpose = nullptr,
                                                                   uint32_t *matrix_stride = nullptr,
                                                                   uint32_t *array_stride = nullptr,
                                                                   bool ptr_chain = false);

    const char *index_to_swizzle(uint32_t index);
    std::string remap_swizzle(const SPIRType &result_type, uint32_t input_components, const std::string &expr);
    std::string declare_temporary(uint32_t type, uint32_t id);
    void emit_uninitialized_temporary(uint32_t type, uint32_t id);
    SPIRExpression &emit_uninitialized_temporary_expression(uint32_t type, uint32_t id);
    void append_global_func_args(const SPIRFunction &func, uint32_t index, SmallVector<std::string> &arglist);
    std::string to_non_uniform_aware_expression(uint32_t id);
    std::string to_expression(uint32_t id, bool register_expression_read = true);
    std::string to_composite_constructor_expression(const SPIRType &parent_type, uint32_t id, bool block_like_type);
    std::string to_rerolled_array_expression(const SPIRType &parent_type, const std::string &expr, const SPIRType &type);
    std::string to_enclosed_expression(uint32_t id, bool register_expression_read = true);
    std::string to_unpacked_expression(uint32_t id, bool register_expression_read = true);
    std::string to_unpacked_row_major_matrix_expression(uint32_t id);
    std::string to_enclosed_unpacked_expression(uint32_t id, bool register_expression_read = true);
    std::string to_dereferenced_expression(uint32_t id, bool register_expression_read = true);
    std::string to_pointer_expression(uint32_t id, bool register_expression_read = true);
    std::string to_enclosed_pointer_expression(uint32_t id, bool register_expression_read = true);
    std::string to_extract_component_expression(uint32_t id, uint32_t index);
    std::string to_extract_constant_composite_expression(uint32_t result_type, const SPIRConstant &c,
                                                         const uint32_t *chain, uint32_t length);
    static bool needs_enclose_expression(const std::string &expr);
    std::string enclose_expression(const std::string &expr);
    std::string dereference_expression(const SPIRType &expression_type, const std::string &expr);
    std::string address_of_expression(const std::string &expr);
    void strip_enclosed_expression(std::string &expr);
    std::string to_member_name(const SPIRType &type, uint32_t index);
    virtual std::string to_member_reference(uint32_t base, const SPIRType &type, uint32_t index, bool ptr_chain_is_resolved);
    std::string to_multi_member_reference(const SPIRType &type, const SmallVector<uint32_t> &indices);
    std::string type_to_glsl_constructor(const SPIRType &type);
    std::string argument_decl(const SPIRFunction::Parameter &arg);
    virtual std::string to_qualifiers_glsl(uint32_t id);
    void fixup_io_block_patch_primitive_qualifiers(const SPIRVariable &var);
    void emit_output_variable_initializer(const SPIRVariable &var);
    std::string to_precision_qualifiers_glsl(uint32_t id);
    virtual const char *to_storage_qualifiers_glsl(const SPIRVariable &var);
    std::string flags_to_qualifiers_glsl(const SPIRType &type, const Bitset &flags);
    const char *format_to_glsl(spv::ImageFormat format);
    virtual std::string layout_for_member(const SPIRType &type, uint32_t index);
    virtual std::string to_interpolation_qualifiers(const Bitset &flags);
    std::string layout_for_variable(const SPIRVariable &variable);
    std::string to_combined_image_sampler(VariableID image_id, VariableID samp_id);
    virtual bool skip_argument(uint32_t id) const;
    virtual bool emit_array_copy(const char *expr, uint32_t lhs_id, uint32_t rhs_id,
                                 spv::StorageClass lhs_storage, spv::StorageClass rhs_storage);
    virtual void emit_block_hints(const SPIRBlock &block);
    virtual std::string to_initializer_expression(const SPIRVariable &var);
    virtual std::string to_zero_initialized_expression(uint32_t type_id);
    bool type_can_zero_initialize(const SPIRType &type) const;

    bool buffer_is_packing_standard(const SPIRType &type, BufferPackingStandard packing,
                                    uint32_t *failed_index = nullptr, uint32_t start_offset = 0,
                                    uint32_t end_offset = ~(0u));
    std::string buffer_to_packing_standard(const SPIRType &type,
                                           bool support_std430_without_scalar_layout,
                                           bool support_enhanced_layouts);

    uint32_t type_to_packed_base_size(const SPIRType &type, BufferPackingStandard packing);
    uint32_t type_to_packed_alignment(const SPIRType &type, const Bitset &flags, BufferPackingStandard packing);
    uint32_t type_to_packed_array_stride(const SPIRType &type, const Bitset &flags, BufferPackingStandard packing);
    uint32_t type_to_packed_size(const SPIRType &type, const Bitset &flags, BufferPackingStandard packing);
    uint32_t type_to_location_count(const SPIRType &type) const;

    std::string bitcast_glsl(const SPIRType &result_type, uint32_t arg);
    virtual std::string bitcast_glsl_op(const SPIRType &result_type, const SPIRType &argument_type);

    std::string bitcast_expression(SPIRType::BaseType target_type, uint32_t arg);
    std::string bitcast_expression(const SPIRType &target_type, SPIRType::BaseType expr_type, const std::string &expr);

    std::string build_composite_combiner(uint32_t result_type, const uint32_t *elems, uint32_t length);
    bool remove_duplicate_swizzle(std::string &op);
    bool remove_unity_swizzle(uint32_t base, std::string &op);

    // Can modify flags to remote readonly/writeonly if image type
    // and force recompile.
    bool check_atomic_image(uint32_t id);

    virtual void replace_illegal_names();
    void replace_illegal_names(const std::unordered_set<std::string> &keywords);
    virtual void emit_entry_point_declarations();

    void replace_fragment_output(SPIRVariable &var);
    void replace_fragment_outputs();
    std::string legacy_tex_op(const std::string &op, const SPIRType &imgtype, uint32_t id);

    void forward_relaxed_precision(uint32_t dst_id, const uint32_t *args, uint32_t length);
    void analyze_precision_requirements(uint32_t type_id, uint32_t dst_id, uint32_t *args, uint32_t length);
    Options::Precision analyze_expression_precision(const uint32_t *args, uint32_t length) const;

    uint32_t indent = 0;

    std::unordered_set<uint32_t> emitted_functions;

    // Ensure that we declare phi-variable copies even if the original declaration isn't deferred
    std::unordered_set<uint32_t> flushed_phi_variables;

    std::unordered_set<uint32_t> flattened_buffer_blocks;
    std::unordered_map<uint32_t, bool> flattened_structs;

    ShaderSubgroupSupportHelper shader_subgroup_supporter;

    std::string load_flattened_struct(const std::string &basename, const SPIRType &type);
    std::string to_flattened_struct_member(const std::string &basename, const SPIRType &type, uint32_t index);
    void store_flattened_struct(uint32_t lhs_id, uint32_t value);
    void store_flattened_struct(const std::string &basename, uint32_t rhs, const SPIRType &type,
                                const SmallVector<uint32_t> &indices);
    std::string to_flattened_access_chain_expression(uint32_t id);

    // Usage tracking. If a temporary is used more than once, use the temporary instead to
    // avoid AST explosion when SPIRV is generated with pure SSA and doesn't write stuff to variables.
    std::unordered_map<uint32_t, uint32_t> expression_usage_counts;
    void track_expression_read(uint32_t id);

    SmallVector<std::string> forced_extensions;
    SmallVector<std::string> header_lines;

    // Used when expressions emit extra opcodes with their own unique IDs,
    // and we need to reuse the IDs across recompilation loops.
    // Currently used by NMin/Max/Clamp implementations.
    std::unordered_map<uint32_t, uint32_t> extra_sub_expressions;

    SmallVector<TypeID> workaround_ubo_load_overload_types;
    void request_workaround_wrapper_overload(TypeID id);
    void rewrite_load_for_wrapped_row_major(std::string &expr, TypeID loaded_type, ID ptr);

    uint32_t statement_count = 0;

    inline bool is_legacy() const
    {
        return (options.es && options.version < 300) || (!options.es && options.version < 130);
    }

    inline bool is_legacy_es() const
    {
        return options.es && options.version < 300;
    }

    inline bool is_legacy_desktop() const
    {
        return !options.es && options.version < 130;
    }

    enum Polyfill : uint32_t
    {
        PolyfillTranspose2x2 = 1 << 0,
        PolyfillTranspose3x3 = 1 << 1,
        PolyfillTranspose4x4 = 1 << 2,
        PolyfillDeterminant2x2 = 1 << 3,
        PolyfillDeterminant3x3 = 1 << 4,
        PolyfillDeterminant4x4 = 1 << 5,
        PolyfillMatrixInverse2x2 = 1 << 6,
        PolyfillMatrixInverse3x3 = 1 << 7,
        PolyfillMatrixInverse4x4 = 1 << 8,
        PolyfillNMin16 = 1 << 9,
        PolyfillNMin32 = 1 << 10,
        PolyfillNMin64 = 1 << 11,
        PolyfillNMax16 = 1 << 12,
        PolyfillNMax32 = 1 << 13,
        PolyfillNMax64 = 1 << 14,
        PolyfillNClamp16 = 1 << 15,
        PolyfillNClamp32 = 1 << 16,
        PolyfillNClamp64 = 1 << 17,
    };

    uint32_t required_polyfills = 0;
    uint32_t required_polyfills_relaxed = 0;
    void require_polyfill(Polyfill polyfill, bool relaxed);

    bool ray_tracing_is_khr = false;
    bool barycentric_is_nv = false;
    void ray_tracing_khr_fixup_locations();

    bool args_will_forward(uint32_t id, const uint32_t *args, uint32_t num_args, bool pure);
    void register_call_out_argument(uint32_t id);
    void register_impure_function_call();
    void register_control_dependent_expression(uint32_t expr);

    // GL_EXT_shader_pixel_local_storage support.
    std::vector<PlsRemap> pls_inputs;
    std::vector<PlsRemap> pls_outputs;
    std::string pls_decl(const PlsRemap &variable);
    const char *to_pls_qualifiers_glsl(const SPIRVariable &variable);
    void emit_pls();
    void remap_pls_variables();

    // GL_EXT_shader_framebuffer_fetch support.
    std::vector<std::pair<uint32_t, uint32_t>> subpass_to_framebuffer_fetch_attachment;
    std::vector<std::pair<uint32_t, bool>> inout_color_attachments;
    bool location_is_framebuffer_fetch(uint32_t location) const;
    bool location_is_non_coherent_framebuffer_fetch(uint32_t location) const;
    bool subpass_input_is_framebuffer_fetch(uint32_t id) const;
    void emit_inout_fragment_outputs_copy_to_subpass_inputs();
    const SPIRVariable *find_subpass_input_by_attachment_index(uint32_t index) const;
    const SPIRVariable *find_color_output_by_location(uint32_t location) const;

    // A variant which takes two sets of name. The secondary is only used to verify there are no collisions,
    // but the set is not updated when we have found a new name.
    // Used primarily when adding block interface names.
    void add_variable(std::unordered_set<std::string> &variables_primary,
                      const std::unordered_set<std::string> &variables_secondary, std::string &name);

    void check_function_call_constraints(const uint32_t *args, uint32_t length);
    void handle_invalid_expression(uint32_t id);
    void force_temporary_and_recompile(uint32_t id);
    void find_static_extensions();

    uint32_t consume_temporary_in_precision_context(uint32_t type_id, uint32_t id, Options::Precision precision);
    std::unordered_map<uint32_t, uint32_t> temporary_to_mirror_precision_alias;
    std::unordered_set<uint32_t> composite_insert_overwritten;
    std::unordered_set<uint32_t> block_composite_insert_overwrite;

    std::string emit_for_loop_initializers(const SPIRBlock &block);
    void emit_while_loop_initializers(const SPIRBlock &block);
    bool for_loop_initializers_are_same_type(const SPIRBlock &block);
    bool optimize_read_modify_write(const SPIRType &type, const std::string &lhs, const std::string &rhs);
    void fixup_image_load_store_access();

    bool type_is_empty(const SPIRType &type);

    bool can_use_io_location(spv::StorageClass storage, bool block);
    const Instruction *get_next_instruction_in_block(const Instruction &instr);
    static uint32_t mask_relevant_memory_semantics(uint32_t semantics);

    std::string convert_half_to_string(const SPIRConstant &value, uint32_t col, uint32_t row);
    std::string convert_float_to_string(const SPIRConstant &value, uint32_t col, uint32_t row);
    std::string convert_double_to_string(const SPIRConstant &value, uint32_t col, uint32_t row);

    std::string convert_separate_image_to_expression(uint32_t id);

    // Builtins in GLSL are always specific signedness, but the SPIR-V can declare them
    // as either unsigned or signed.
    // Sometimes we will need to automatically perform casts on load and store to make this work.
    virtual SPIRType::BaseType get_builtin_basetype(spv::BuiltIn builtin, SPIRType::BaseType default_type);
    virtual void cast_to_variable_store(uint32_t target_id, std::string &expr, const SPIRType &expr_type);
    virtual void cast_from_variable_load(uint32_t source_id, std::string &expr, const SPIRType &expr_type);
    void unroll_array_from_complex_load(uint32_t target_id, uint32_t source_id, std::string &expr);
    bool unroll_array_to_complex_store(uint32_t target_id, uint32_t source_id);
    void convert_non_uniform_expression(std::string &expr, uint32_t ptr_id);

    void handle_store_to_invariant_variable(uint32_t store_id, uint32_t value_id);
    void disallow_forwarding_in_expression_chain(const SPIRExpression &expr);

    bool expression_is_constant_null(uint32_t id) const;
    bool expression_is_non_value_type_array(uint32_t ptr);
    virtual void emit_store_statement(uint32_t lhs_expression, uint32_t rhs_expression);

    uint32_t get_integer_width_for_instruction(const Instruction &instr) const;
    uint32_t get_integer_width_for_glsl_instruction(GLSLstd450 op, const uint32_t *arguments, uint32_t length) const;

    bool variable_is_lut(const SPIRVariable &var) const;

    char current_locale_radix_character = '.';

    void fixup_type_alias();
    void reorder_type_alias();
    void fixup_anonymous_struct_names();
    void fixup_anonymous_struct_names(std::unordered_set<uint32_t> &visited, const SPIRType &type);

    static const char *vector_swizzle(int vecsize, int index);

    bool is_stage_output_location_masked(uint32_t location, uint32_t component) const;
    bool is_stage_output_builtin_masked(spv::BuiltIn builtin) const;
    bool is_stage_output_variable_masked(const SPIRVariable &var) const;
    bool is_stage_output_block_member_masked(const SPIRVariable &var, uint32_t index, bool strip_array) const;
    bool is_per_primitive_variable(const SPIRVariable &var) const;
    uint32_t get_accumulated_member_location(const SPIRVariable &var, uint32_t mbr_idx, bool strip_array) const;
    uint32_t get_declared_member_location(const SPIRVariable &var, uint32_t mbr_idx, bool strip_array) const;
    std::unordered_set<LocationComponentPair, InternalHasher> masked_output_locations;
    std::unordered_set<uint32_t> masked_output_builtins;

    FloatFormatter *float_formatter = nullptr;
    std::string format_float(float value) const;
    std::string format_double(double value) const;

private:
    void init();

    SmallVector<ConstantID> get_composite_constant_ids(ConstantID const_id);
    void fill_composite_constant(SPIRConstant &constant, TypeID type_id, const SmallVector<ConstantID> &initializers);
    void set_composite_constant(ConstantID const_id, TypeID type_id, const SmallVector<ConstantID> &initializers);
    TypeID get_composite_member_type(TypeID type_id, uint32_t member_idx);
    std::unordered_map<uint32_t, SmallVector<ConstantID>> const_composite_insert_ids;
};
} // namespace SPIRV_CROSS_NAMESPACE

#endif