spirv_reflect.cpp - third_party/spirv-cross - Git at Google

 /*
  * Copyright 2018-2020 Bradley Austin Davis
  *
  * 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>.
  * SPDX-License-Identifier: Apache-2.0 OR MIT.
  */

 #include "spirv_reflect.hpp"
 #include "spirv_glsl.hpp"
 #include <iomanip>

 using namespace spv;
 using namespace SPIRV_CROSS_NAMESPACE;
 using namespace std;

 namespace simple_json
 {
 enum class Type
 {
 	Object,
 	Array,
 };

 using State = std::pair<Type, bool>;
 using Stack = std::stack<State>;

 class Stream
 {
 	Stack stack;
 	StringStream<> buffer;
 	uint32_t indent{ 0 };
 	char current_locale_radix_character = '.';

 public:
 	void set_current_locale_radix_character(char c)
 	{
 		current_locale_radix_character = c;
 	}

 	void begin_json_object();
 	void end_json_object();
 	void emit_json_key(const std::string &key);
 	void emit_json_key_value(const std::string &key, const std::string &value);
 	void emit_json_key_value(const std::string &key, bool value);
 	void emit_json_key_value(const std::string &key, uint32_t value);
 	void emit_json_key_value(const std::string &key, int32_t value);
 	void emit_json_key_value(const std::string &key, float value);
 	void emit_json_key_object(const std::string &key);
 	void emit_json_key_array(const std::string &key);

 	void begin_json_array();
 	void end_json_array();
 	void emit_json_array_value(const std::string &value);
 	void emit_json_array_value(uint32_t value);
 	void emit_json_array_value(bool value);

 	std::string str() const
 	{
 		return buffer.str();
 	}

 private:
 	inline void statement_indent()
 	{
 		for (uint32_t i = 0; i < indent; i++)
 			buffer << "    ";
 	}

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

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

 	template <typename... Ts>
 	inline void statement(Ts &&... ts)
 	{
 		statement_indent();
 		statement_inner(std::forward<Ts>(ts)...);
 		buffer << '\n';
 	}

 	template <typename... Ts>
 	void statement_no_return(Ts &&... ts)
 	{
 		statement_indent();
 		statement_inner(std::forward<Ts>(ts)...);
 	}
 };
 } // namespace simple_json

 using namespace simple_json;

 // Hackery to emit JSON without using nlohmann/json C++ library (which requires a
 // higher level of compiler compliance than is required by SPIRV-Cross
 void Stream::begin_json_array()
 {
 	if (!stack.empty() && stack.top().second)
 	{
 		statement_inner(",\n");
 	}
 	statement("[");
 	++indent;
 	stack.emplace(Type::Array, false);
 }

 void Stream::end_json_array()
 {
 	if (stack.empty() || stack.top().first != Type::Array)
 		SPIRV_CROSS_THROW("Invalid JSON state");
 	if (stack.top().second)
 	{
 		statement_inner("\n");
 	}
 	--indent;
 	statement_no_return("]");
 	stack.pop();
 	if (!stack.empty())
 	{
 		stack.top().second = true;
 	}
 }

 void Stream::emit_json_array_value(const std::string &value)
 {
 	if (stack.empty() || stack.top().first != Type::Array)
 		SPIRV_CROSS_THROW("Invalid JSON state");

 	if (stack.top().second)
 		statement_inner(",\n");

 	statement_no_return("\"", value, "\"");
 	stack.top().second = true;
 }

 void Stream::emit_json_array_value(uint32_t value)
 {
 	if (stack.empty() || stack.top().first != Type::Array)
 		SPIRV_CROSS_THROW("Invalid JSON state");
 	if (stack.top().second)
 		statement_inner(",\n");
 	statement_no_return(std::to_string(value));
 	stack.top().second = true;
 }

 void Stream::emit_json_array_value(bool value)
 {
 	if (stack.empty() || stack.top().first != Type::Array)
 		SPIRV_CROSS_THROW("Invalid JSON state");
 	if (stack.top().second)
 		statement_inner(",\n");
 	statement_no_return(value ? "true" : "false");
 	stack.top().second = true;
 }

 void Stream::begin_json_object()
 {
 	if (!stack.empty() && stack.top().second)
 	{
 		statement_inner(",\n");
 	}
 	statement("{");
 	++indent;
 	stack.emplace(Type::Object, false);
 }

 void Stream::end_json_object()
 {
 	if (stack.empty() || stack.top().first != Type::Object)
 		SPIRV_CROSS_THROW("Invalid JSON state");
 	if (stack.top().second)
 	{
 		statement_inner("\n");
 	}
 	--indent;
 	statement_no_return("}");
 	stack.pop();
 	if (!stack.empty())
 	{
 		stack.top().second = true;
 	}
 }

 void Stream::emit_json_key(const std::string &key)
 {
 	if (stack.empty() || stack.top().first != Type::Object)
 		SPIRV_CROSS_THROW("Invalid JSON state");

 	if (stack.top().second)
 		statement_inner(",\n");
 	statement_no_return("\"", key, "\" : ");
 	stack.top().second = true;
 }

 void Stream::emit_json_key_value(const std::string &key, const std::string &value)
 {
 	emit_json_key(key);
 	statement_inner("\"", value, "\"");
 }

 void Stream::emit_json_key_value(const std::string &key, uint32_t value)
 {
 	emit_json_key(key);
 	statement_inner(value);
 }

 void Stream::emit_json_key_value(const std::string &key, int32_t value)
 {
 	emit_json_key(key);
 	statement_inner(value);
 }

 void Stream::emit_json_key_value(const std::string &key, float value)
 {
 	emit_json_key(key);
 	statement_inner(convert_to_string(value, current_locale_radix_character));
 }

 void Stream::emit_json_key_value(const std::string &key, bool value)
 {
 	emit_json_key(key);
 	statement_inner(value ? "true" : "false");
 }

 void Stream::emit_json_key_object(const std::string &key)
 {
 	emit_json_key(key);
 	statement_inner("{\n");
 	++indent;
 	stack.emplace(Type::Object, false);
 }

 void Stream::emit_json_key_array(const std::string &key)
 {
 	emit_json_key(key);
 	statement_inner("[\n");
 	++indent;
 	stack.emplace(Type::Array, false);
 }

 void CompilerReflection::set_format(const std::string &format)
 {
 	if (format != "json")
 	{
 		SPIRV_CROSS_THROW("Unsupported format");
 	}
 }

 string CompilerReflection::compile()
 {
 	json_stream = std::make_shared<simple_json::Stream>();
 	json_stream->set_current_locale_radix_character(current_locale_radix_character);
 	json_stream->begin_json_object();
 	reorder_type_alias();
 	emit_entry_points();
 	emit_types();
 	emit_resources();
 	emit_specialization_constants();
 	json_stream->end_json_object();
 	return json_stream->str();
 }

 static bool naturally_emit_type(const SPIRType &type)
 {
 	return type.basetype == SPIRType::Struct && !type.pointer && type.array.empty();
 }

 bool CompilerReflection::type_is_reference(const SPIRType &type) const
 {
 	// Physical pointers and arrays of physical pointers need to refer to the pointee's type.
 	return type_is_top_level_physical_pointer(type) ||
 	       (!type.array.empty() && type_is_top_level_physical_pointer(get<SPIRType>(type.parent_type)));
 }

 void CompilerReflection::emit_types()
 {
 	bool emitted_open_tag = false;

 	SmallVector<uint32_t> physical_pointee_types;

 	// If we have physical pointers or arrays of physical pointers, it's also helpful to emit the pointee type
 	// and chain the type hierarchy. For POD, arrays can emit the entire type in-place.
 	ir.for_each_typed_id<SPIRType>([&](uint32_t self, SPIRType &type) {
 		if (naturally_emit_type(type))
 		{
 			emit_type(self, emitted_open_tag);
 		}
 		else if (type_is_reference(type))
 		{
 			if (!naturally_emit_type(this->get<SPIRType>(type.parent_type)) &&
 			    find(physical_pointee_types.begin(), physical_pointee_types.end(), type.parent_type) ==
 			        physical_pointee_types.end())
 			{
 				physical_pointee_types.push_back(type.parent_type);
 			}
 		}
 	});

 	for (uint32_t pointee_type : physical_pointee_types)
 		emit_type(pointee_type, emitted_open_tag);

 	if (emitted_open_tag)
 	{
 		json_stream->end_json_object();
 	}
 }

 void CompilerReflection::emit_type(uint32_t type_id, bool &emitted_open_tag)
 {
 	auto &type = get<SPIRType>(type_id);
 	auto name = type_to_glsl(type);

 	if (!emitted_open_tag)
 	{
 		json_stream->emit_json_key_object("types");
 		emitted_open_tag = true;
 	}
 	json_stream->emit_json_key_object("_" + std::to_string(type_id));
 	json_stream->emit_json_key_value("name", name);

 	if (type_is_top_level_physical_pointer(type))
 	{
 		json_stream->emit_json_key_value("type", "_" + std::to_string(type.parent_type));
 		json_stream->emit_json_key_value("physical_pointer", true);
 	}
 	else if (!type.array.empty())
 	{
 		emit_type_array(type);
 		json_stream->emit_json_key_value("type", "_" + std::to_string(type.parent_type));
 		json_stream->emit_json_key_value("array_stride", get_decoration(type_id, DecorationArrayStride));
 	}
 	else
 	{
 		json_stream->emit_json_key_array("members");
 		// FIXME ideally we'd like to emit the size of a structure as a
 		// convenience to people parsing the reflected JSON.  The problem
 		// is that there's no implicit size for a type.  It's final size
 		// will be determined by the top level declaration in which it's
 		// included.  So there might be one size for the struct if it's
 		// included in a std140 uniform block and another if it's included
 		// in a std430 uniform block.
 		// The solution is to include *all* potential sizes as a map of
 		// layout type name to integer, but that will probably require
 		// some additional logic being written in this class, or in the
 		// parent CompilerGLSL class.
 		auto size = type.member_types.size();
 		for (uint32_t i = 0; i < size; ++i)
 		{
 			emit_type_member(type, i);
 		}
 		json_stream->end_json_array();
 	}

 	json_stream->end_json_object();
 }

 void CompilerReflection::emit_type_member(const SPIRType &type, uint32_t index)
 {
 	auto &membertype = get<SPIRType>(type.member_types[index]);
 	json_stream->begin_json_object();
 	auto name = to_member_name(type, index);
 	// FIXME we'd like to emit the offset of each member, but such offsets are
 	// context dependent.  See the comment above regarding structure sizes
 	json_stream->emit_json_key_value("name", name);

 	if (type_is_reference(membertype))
 	{
 		json_stream->emit_json_key_value("type", "_" + std::to_string(membertype.parent_type));
 	}
 	else if (membertype.basetype == SPIRType::Struct)
 	{
 		json_stream->emit_json_key_value("type", "_" + std::to_string(membertype.self));
 	}
 	else
 	{
 		json_stream->emit_json_key_value("type", type_to_glsl(membertype));
 	}
 	emit_type_member_qualifiers(type, index);
 	json_stream->end_json_object();
 }

 void CompilerReflection::emit_type_array(const SPIRType &type)
 {
 	if (!type_is_top_level_physical_pointer(type) && !type.array.empty())
 	{
 		json_stream->emit_json_key_array("array");
 		// Note that we emit the zeros here as a means of identifying
 		// unbounded arrays.  This is necessary as otherwise there would
 		// be no way of differentiating between float[4] and float[4][]
 		for (const auto &value : type.array)
 			json_stream->emit_json_array_value(value);
 		json_stream->end_json_array();

 		json_stream->emit_json_key_array("array_size_is_literal");
 		for (const auto &value : type.array_size_literal)
 			json_stream->emit_json_array_value(value);
 		json_stream->end_json_array();
 	}
 }

 void CompilerReflection::emit_type_member_qualifiers(const SPIRType &type, uint32_t index)
 {
 	auto &membertype = get<SPIRType>(type.member_types[index]);
 	emit_type_array(membertype);
 	auto &memb = ir.meta[type.self].members;
 	if (index < memb.size())
 	{
 		auto &dec = memb[index];
 		if (dec.decoration_flags.get(DecorationLocation))
 			json_stream->emit_json_key_value("location", dec.location);
 		if (dec.decoration_flags.get(DecorationOffset))
 			json_stream->emit_json_key_value("offset", dec.offset);

 		// Array stride is a property of the array type, not the struct.
 		if (has_decoration(type.member_types[index], DecorationArrayStride))
 			json_stream->emit_json_key_value("array_stride",
 			                                 get_decoration(type.member_types[index], DecorationArrayStride));

 		if (dec.decoration_flags.get(DecorationMatrixStride))
 			json_stream->emit_json_key_value("matrix_stride", dec.matrix_stride);
 		if (dec.decoration_flags.get(DecorationRowMajor))
 			json_stream->emit_json_key_value("row_major", true);

 		if (type_is_top_level_physical_pointer(membertype))
 			json_stream->emit_json_key_value("physical_pointer", true);
 	}
 }

 string CompilerReflection::execution_model_to_str(spv::ExecutionModel model)
 {
 	switch (model)
 	{
 	case ExecutionModelVertex:
 		return "vert";
 	case ExecutionModelTessellationControl:
 		return "tesc";
 	case ExecutionModelTessellationEvaluation:
 		return "tese";
 	case ExecutionModelGeometry:
 		return "geom";
 	case ExecutionModelFragment:
 		return "frag";
 	case ExecutionModelGLCompute:
 		return "comp";
 	case ExecutionModelRayGenerationNV:
 		return "rgen";
 	case ExecutionModelIntersectionNV:
 		return "rint";
 	case ExecutionModelAnyHitNV:
 		return "rahit";
 	case ExecutionModelClosestHitNV:
 		return "rchit";
 	case ExecutionModelMissNV:
 		return "rmiss";
 	case ExecutionModelCallableNV:
 		return "rcall";
 	default:
 		return "???";
 	}
 }

 // FIXME include things like the local_size dimensions, geometry output vertex count, etc
 void CompilerReflection::emit_entry_points()
 {
 	auto entries = get_entry_points_and_stages();
 	if (!entries.empty())
 	{
 		// Needed to make output deterministic.
 		sort(begin(entries), end(entries), [](const EntryPoint &a, const EntryPoint &b) -> bool {
 			if (a.execution_model < b.execution_model)
 				return true;
 			else if (a.execution_model > b.execution_model)
 				return false;
 			else
 				return a.name < b.name;
 		});

 		json_stream->emit_json_key_array("entryPoints");
 		for (auto &e : entries)
 		{
 			json_stream->begin_json_object();
 			json_stream->emit_json_key_value("name", e.name);
 			json_stream->emit_json_key_value("mode", execution_model_to_str(e.execution_model));
 			if (e.execution_model == ExecutionModelGLCompute)
 			{
 				const auto &spv_entry = get_entry_point(e.name, e.execution_model);

 				SpecializationConstant spec_x, spec_y, spec_z;
 				get_work_group_size_specialization_constants(spec_x, spec_y, spec_z);

 				json_stream->emit_json_key_array("workgroup_size");
 				json_stream->emit_json_array_value(spec_x.id != ID(0) ? spec_x.constant_id :
 				                                                        spv_entry.workgroup_size.x);
 				json_stream->emit_json_array_value(spec_y.id != ID(0) ? spec_y.constant_id :
 				                                                        spv_entry.workgroup_size.y);
 				json_stream->emit_json_array_value(spec_z.id != ID(0) ? spec_z.constant_id :
 				                                                        spv_entry.workgroup_size.z);
 				json_stream->end_json_array();

 				json_stream->emit_json_key_array("workgroup_size_is_spec_constant_id");
 				json_stream->emit_json_array_value(spec_x.id != ID(0));
 				json_stream->emit_json_array_value(spec_y.id != ID(0));
 				json_stream->emit_json_array_value(spec_z.id != ID(0));
 				json_stream->end_json_array();
 			}
 			json_stream->end_json_object();
 		}
 		json_stream->end_json_array();
 	}
 }

 void CompilerReflection::emit_resources()
 {
 	auto res = get_shader_resources();
 	emit_resources("subpass_inputs", res.subpass_inputs);
 	emit_resources("inputs", res.stage_inputs);
 	emit_resources("outputs", res.stage_outputs);
 	emit_resources("textures", res.sampled_images);
 	emit_resources("separate_images", res.separate_images);
 	emit_resources("separate_samplers", res.separate_samplers);
 	emit_resources("images", res.storage_images);
 	emit_resources("ssbos", res.storage_buffers);
 	emit_resources("ubos", res.uniform_buffers);
 	emit_resources("push_constants", res.push_constant_buffers);
 	emit_resources("counters", res.atomic_counters);
 	emit_resources("acceleration_structures", res.acceleration_structures);
 }

 void CompilerReflection::emit_resources(const char *tag, const SmallVector<Resource> &resources)
 {
 	if (resources.empty())
 	{
 		return;
 	}

 	json_stream->emit_json_key_array(tag);
 	for (auto &res : resources)
 	{
 		auto &type = get_type(res.type_id);
 		auto typeflags = ir.meta[type.self].decoration.decoration_flags;
 		auto &mask = get_decoration_bitset(res.id);

 		// If we don't have a name, use the fallback for the type instead of the variable
 		// for SSBOs and UBOs since those are the only meaningful names to use externally.
 		// Push constant blocks are still accessed by name and not block name, even though they are technically Blocks.
 		bool is_push_constant = get_storage_class(res.id) == StorageClassPushConstant;
 		bool is_block = get_decoration_bitset(type.self).get(DecorationBlock) ||
 		                get_decoration_bitset(type.self).get(DecorationBufferBlock);

 		ID fallback_id = !is_push_constant && is_block ? ID(res.base_type_id) : ID(res.id);

 		json_stream->begin_json_object();

 		if (type.basetype == SPIRType::Struct)
 		{
 			json_stream->emit_json_key_value("type", "_" + std::to_string(res.base_type_id));
 		}
 		else
 		{
 			json_stream->emit_json_key_value("type", type_to_glsl(type));
 		}

 		json_stream->emit_json_key_value("name", !res.name.empty() ? res.name : get_fallback_name(fallback_id));
 		{
 			bool ssbo_block = type.storage == StorageClassStorageBuffer ||
 			                  (type.storage == StorageClassUniform && typeflags.get(DecorationBufferBlock));
 			if (ssbo_block)
 			{
 				auto buffer_flags = get_buffer_block_flags(res.id);
 				if (buffer_flags.get(DecorationNonReadable))
 					json_stream->emit_json_key_value("writeonly", true);
 				if (buffer_flags.get(DecorationNonWritable))
 					json_stream->emit_json_key_value("readonly", true);
 				if (buffer_flags.get(DecorationRestrict))
 					json_stream->emit_json_key_value("restrict", true);
 				if (buffer_flags.get(DecorationCoherent))
 					json_stream->emit_json_key_value("coherent", true);
 			}
 		}

 		emit_type_array(type);

 		{
 			bool is_sized_block = is_block && (get_storage_class(res.id) == StorageClassUniform ||
 			                                   get_storage_class(res.id) == StorageClassUniformConstant ||
 			                                   get_storage_class(res.id) == StorageClassStorageBuffer);
 			if (is_sized_block)
 			{
 				uint32_t block_size = uint32_t(get_declared_struct_size(get_type(res.base_type_id)));
 				json_stream->emit_json_key_value("block_size", block_size);
 			}
 		}

 		if (type.storage == StorageClassPushConstant)
 			json_stream->emit_json_key_value("push_constant", true);
 		if (mask.get(DecorationLocation))
 			json_stream->emit_json_key_value("location", get_decoration(res.id, DecorationLocation));
 		if (mask.get(DecorationRowMajor))
 			json_stream->emit_json_key_value("row_major", true);
 		if (mask.get(DecorationColMajor))
 			json_stream->emit_json_key_value("column_major", true);
 		if (mask.get(DecorationIndex))
 			json_stream->emit_json_key_value("index", get_decoration(res.id, DecorationIndex));
 		if (type.storage != StorageClassPushConstant && mask.get(DecorationDescriptorSet))
 			json_stream->emit_json_key_value("set", get_decoration(res.id, DecorationDescriptorSet));
 		if (mask.get(DecorationBinding))
 			json_stream->emit_json_key_value("binding", get_decoration(res.id, DecorationBinding));
 		if (mask.get(DecorationInputAttachmentIndex))
 			json_stream->emit_json_key_value("input_attachment_index",
 			                                 get_decoration(res.id, DecorationInputAttachmentIndex));
 		if (mask.get(DecorationOffset))
 			json_stream->emit_json_key_value("offset", get_decoration(res.id, DecorationOffset));

 		// For images, the type itself adds a layout qualifer.
 		// Only emit the format for storage images.
 		if (type.basetype == SPIRType::Image && type.image.sampled == 2)
 		{
 			const char *fmt = format_to_glsl(type.image.format);
 			if (fmt != nullptr)
 				json_stream->emit_json_key_value("format", std::string(fmt));
 		}
 		json_stream->end_json_object();
 	}
 	json_stream->end_json_array();
 }

 void CompilerReflection::emit_specialization_constants()
 {
 	auto specialization_constants = get_specialization_constants();
 	if (specialization_constants.empty())
 		return;

 	json_stream->emit_json_key_array("specialization_constants");
 	for (const auto &spec_const : specialization_constants)
 	{
 		auto &c = get<SPIRConstant>(spec_const.id);
 		auto type = get<SPIRType>(c.constant_type);
 		json_stream->begin_json_object();
 		json_stream->emit_json_key_value("name", get_name(spec_const.id));
 		json_stream->emit_json_key_value("id", spec_const.constant_id);
 		json_stream->emit_json_key_value("type", type_to_glsl(type));
 		json_stream->emit_json_key_value("variable_id", spec_const.id);
 		switch (type.basetype)
 		{
 		case SPIRType::UInt:
 			json_stream->emit_json_key_value("default_value", c.scalar());
 			break;

 		case SPIRType::Int:
 			json_stream->emit_json_key_value("default_value", c.scalar_i32());
 			break;

 		case SPIRType::Float:
 			json_stream->emit_json_key_value("default_value", c.scalar_f32());
 			break;

 		case SPIRType::Boolean:
 			json_stream->emit_json_key_value("default_value", c.scalar() != 0);
 			break;

 		default:
 			break;
 		}
 		json_stream->end_json_object();
 	}
 	json_stream->end_json_array();
 }

 string CompilerReflection::to_member_name(const SPIRType &type, uint32_t index) const
 {
 	auto *type_meta = ir.find_meta(type.self);

 	if (type_meta)
 	{
 		auto &memb = type_meta->members;
 		if (index < memb.size() && !memb[index].alias.empty())
 			return memb[index].alias;
 		else
 			return join("_m", index);
 	}
 	else
 		return join("_m", index);
 }
	/*
	* Copyright 2018-2020 Bradley Austin Davis
	*
	* 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>.
	* SPDX-License-Identifier: Apache-2.0 OR MIT.
	*/

	#include "spirv_reflect.hpp"
	#include "spirv_glsl.hpp"
	#include <iomanip>

	using namespace spv;
	using namespace SPIRV_CROSS_NAMESPACE;
	using namespace std;

	namespace simple_json
	{
	enum class Type
	{
	Object,
	Array,
	};

	using State = std::pair<Type, bool>;
	using Stack = std::stack<State>;

	class Stream
	{
	Stack stack;
	StringStream<> buffer;
	uint32_t indent{ 0 };
	char current_locale_radix_character = '.';

	public:
	void set_current_locale_radix_character(char c)
	{
	current_locale_radix_character = c;
	}

	void begin_json_object();
	void end_json_object();
	void emit_json_key(const std::string &key);
	void emit_json_key_value(const std::string &key, const std::string &value);
	void emit_json_key_value(const std::string &key, bool value);
	void emit_json_key_value(const std::string &key, uint32_t value);
	void emit_json_key_value(const std::string &key, int32_t value);
	void emit_json_key_value(const std::string &key, float value);
	void emit_json_key_object(const std::string &key);
	void emit_json_key_array(const std::string &key);

	void begin_json_array();
	void end_json_array();
	void emit_json_array_value(const std::string &value);
	void emit_json_array_value(uint32_t value);
	void emit_json_array_value(bool value);

	std::string str() const
	{
	return buffer.str();
	}

	private:
	inline void statement_indent()
	{
	for (uint32_t i = 0; i < indent; i++)
	buffer << " ";
	}

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

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

	template <typename... Ts>
	inline void statement(Ts &&... ts)
	{
	statement_indent();
	statement_inner(std::forward<Ts>(ts)...);
	buffer << '\n';
	}

	template <typename... Ts>
	void statement_no_return(Ts &&... ts)
	{
	statement_indent();
	statement_inner(std::forward<Ts>(ts)...);
	}
	};
	} // namespace simple_json

	using namespace simple_json;

	// Hackery to emit JSON without using nlohmann/json C++ library (which requires a
	// higher level of compiler compliance than is required by SPIRV-Cross
	void Stream::begin_json_array()
	{
	if (!stack.empty() && stack.top().second)
	{
	statement_inner(",\n");
	}
	statement("[");
	++indent;
	stack.emplace(Type::Array, false);
	}

	void Stream::end_json_array()
	{
	if (stack.empty() \|\| stack.top().first != Type::Array)
	SPIRV_CROSS_THROW("Invalid JSON state");
	if (stack.top().second)
	{
	statement_inner("\n");
	}
	--indent;
	statement_no_return("]");
	stack.pop();
	if (!stack.empty())
	{
	stack.top().second = true;
	}
	}

	void Stream::emit_json_array_value(const std::string &value)
	{
	if (stack.empty() \|\| stack.top().first != Type::Array)
	SPIRV_CROSS_THROW("Invalid JSON state");

	if (stack.top().second)
	statement_inner(",\n");

	statement_no_return("\"", value, "\"");
	stack.top().second = true;
	}

	void Stream::emit_json_array_value(uint32_t value)
	{
	if (stack.empty() \|\| stack.top().first != Type::Array)
	SPIRV_CROSS_THROW("Invalid JSON state");
	if (stack.top().second)
	statement_inner(",\n");
	statement_no_return(std::to_string(value));
	stack.top().second = true;
	}

	void Stream::emit_json_array_value(bool value)
	{
	if (stack.empty() \|\| stack.top().first != Type::Array)
	SPIRV_CROSS_THROW("Invalid JSON state");
	if (stack.top().second)
	statement_inner(",\n");
	statement_no_return(value ? "true" : "false");
	stack.top().second = true;
	}

	void Stream::begin_json_object()
	{
	if (!stack.empty() && stack.top().second)
	{
	statement_inner(",\n");
	}
	statement("{");
	++indent;
	stack.emplace(Type::Object, false);
	}

	void Stream::end_json_object()
	{
	if (stack.empty() \|\| stack.top().first != Type::Object)
	SPIRV_CROSS_THROW("Invalid JSON state");
	if (stack.top().second)
	{
	statement_inner("\n");
	}
	--indent;
	statement_no_return("}");
	stack.pop();
	if (!stack.empty())
	{
	stack.top().second = true;
	}
	}

	void Stream::emit_json_key(const std::string &key)
	{
	if (stack.empty() \|\| stack.top().first != Type::Object)
	SPIRV_CROSS_THROW("Invalid JSON state");

	if (stack.top().second)
	statement_inner(",\n");
	statement_no_return("\"", key, "\" : ");
	stack.top().second = true;
	}

	void Stream::emit_json_key_value(const std::string &key, const std::string &value)
	{
	emit_json_key(key);
	statement_inner("\"", value, "\"");
	}

	void Stream::emit_json_key_value(const std::string &key, uint32_t value)
	{
	emit_json_key(key);
	statement_inner(value);
	}

	void Stream::emit_json_key_value(const std::string &key, int32_t value)
	{
	emit_json_key(key);
	statement_inner(value);
	}

	void Stream::emit_json_key_value(const std::string &key, float value)
	{
	emit_json_key(key);
	statement_inner(convert_to_string(value, current_locale_radix_character));
	}

	void Stream::emit_json_key_value(const std::string &key, bool value)
	{
	emit_json_key(key);
	statement_inner(value ? "true" : "false");
	}

	void Stream::emit_json_key_object(const std::string &key)
	{
	emit_json_key(key);
	statement_inner("{\n");
	++indent;
	stack.emplace(Type::Object, false);
	}

	void Stream::emit_json_key_array(const std::string &key)
	{
	emit_json_key(key);
	statement_inner("[\n");
	++indent;
	stack.emplace(Type::Array, false);
	}

	void CompilerReflection::set_format(const std::string &format)
	{
	if (format != "json")
	{
	SPIRV_CROSS_THROW("Unsupported format");
	}
	}

	string CompilerReflection::compile()
	{
	json_stream = std::make_shared<simple_json::Stream>();
	json_stream->set_current_locale_radix_character(current_locale_radix_character);
	json_stream->begin_json_object();
	reorder_type_alias();
	emit_entry_points();
	emit_types();
	emit_resources();
	emit_specialization_constants();
	json_stream->end_json_object();
	return json_stream->str();
	}

	static bool naturally_emit_type(const SPIRType &type)
	{
	return type.basetype == SPIRType::Struct && !type.pointer && type.array.empty();
	}

	bool CompilerReflection::type_is_reference(const SPIRType &type) const
	{
	// Physical pointers and arrays of physical pointers need to refer to the pointee's type.
	return type_is_top_level_physical_pointer(type) \|\|
	(!type.array.empty() && type_is_top_level_physical_pointer(get<SPIRType>(type.parent_type)));
	}

	void CompilerReflection::emit_types()
	{
	bool emitted_open_tag = false;

	SmallVector<uint32_t> physical_pointee_types;

	// If we have physical pointers or arrays of physical pointers, it's also helpful to emit the pointee type
	// and chain the type hierarchy. For POD, arrays can emit the entire type in-place.
	ir.for_each_typed_id<SPIRType>([&](uint32_t self, SPIRType &type) {
	if (naturally_emit_type(type))
	{
	emit_type(self, emitted_open_tag);
	}
	else if (type_is_reference(type))
	{
	if (!naturally_emit_type(this->get<SPIRType>(type.parent_type)) &&
	find(physical_pointee_types.begin(), physical_pointee_types.end(), type.parent_type) ==
	physical_pointee_types.end())
	{
	physical_pointee_types.push_back(type.parent_type);
	}
	}
	});

	for (uint32_t pointee_type : physical_pointee_types)
	emit_type(pointee_type, emitted_open_tag);

	if (emitted_open_tag)
	{
	json_stream->end_json_object();
	}
	}

	void CompilerReflection::emit_type(uint32_t type_id, bool &emitted_open_tag)
	{
	auto &type = get<SPIRType>(type_id);
	auto name = type_to_glsl(type);

	if (!emitted_open_tag)
	{
	json_stream->emit_json_key_object("types");
	emitted_open_tag = true;
	}
	json_stream->emit_json_key_object("_" + std::to_string(type_id));
	json_stream->emit_json_key_value("name", name);

	if (type_is_top_level_physical_pointer(type))
	{
	json_stream->emit_json_key_value("type", "_" + std::to_string(type.parent_type));
	json_stream->emit_json_key_value("physical_pointer", true);
	}
	else if (!type.array.empty())
	{
	emit_type_array(type);
	json_stream->emit_json_key_value("type", "_" + std::to_string(type.parent_type));
	json_stream->emit_json_key_value("array_stride", get_decoration(type_id, DecorationArrayStride));
	}
	else
	{
	json_stream->emit_json_key_array("members");
	// FIXME ideally we'd like to emit the size of a structure as a
	// convenience to people parsing the reflected JSON. The problem
	// is that there's no implicit size for a type. It's final size
	// will be determined by the top level declaration in which it's
	// included. So there might be one size for the struct if it's
	// included in a std140 uniform block and another if it's included
	// in a std430 uniform block.
	// The solution is to include all potential sizes as a map of
	// layout type name to integer, but that will probably require
	// some additional logic being written in this class, or in the
	// parent CompilerGLSL class.
	auto size = type.member_types.size();
	for (uint32_t i = 0; i < size; ++i)
	{
	emit_type_member(type, i);
	}
	json_stream->end_json_array();
	}

	json_stream->end_json_object();
	}

	void CompilerReflection::emit_type_member(const SPIRType &type, uint32_t index)
	{
	auto &membertype = get<SPIRType>(type.member_types[index]);
	json_stream->begin_json_object();
	auto name = to_member_name(type, index);
	// FIXME we'd like to emit the offset of each member, but such offsets are
	// context dependent. See the comment above regarding structure sizes
	json_stream->emit_json_key_value("name", name);

	if (type_is_reference(membertype))
	{
	json_stream->emit_json_key_value("type", "_" + std::to_string(membertype.parent_type));
	}
	else if (membertype.basetype == SPIRType::Struct)
	{
	json_stream->emit_json_key_value("type", "_" + std::to_string(membertype.self));
	}
	else
	{
	json_stream->emit_json_key_value("type", type_to_glsl(membertype));
	}
	emit_type_member_qualifiers(type, index);
	json_stream->end_json_object();
	}

	void CompilerReflection::emit_type_array(const SPIRType &type)
	{
	if (!type_is_top_level_physical_pointer(type) && !type.array.empty())
	{
	json_stream->emit_json_key_array("array");
	// Note that we emit the zeros here as a means of identifying
	// unbounded arrays. This is necessary as otherwise there would
	// be no way of differentiating between float[4] and float[4][]
	for (const auto &value : type.array)
	json_stream->emit_json_array_value(value);
	json_stream->end_json_array();

	json_stream->emit_json_key_array("array_size_is_literal");
	for (const auto &value : type.array_size_literal)
	json_stream->emit_json_array_value(value);
	json_stream->end_json_array();
	}
	}

	void CompilerReflection::emit_type_member_qualifiers(const SPIRType &type, uint32_t index)
	{
	auto &membertype = get<SPIRType>(type.member_types[index]);
	emit_type_array(membertype);
	auto &memb = ir.meta[type.self].members;
	if (index < memb.size())
	{
	auto &dec = memb[index];
	if (dec.decoration_flags.get(DecorationLocation))
	json_stream->emit_json_key_value("location", dec.location);
	if (dec.decoration_flags.get(DecorationOffset))
	json_stream->emit_json_key_value("offset", dec.offset);

	// Array stride is a property of the array type, not the struct.
	if (has_decoration(type.member_types[index], DecorationArrayStride))
	json_stream->emit_json_key_value("array_stride",
	get_decoration(type.member_types[index], DecorationArrayStride));

	if (dec.decoration_flags.get(DecorationMatrixStride))
	json_stream->emit_json_key_value("matrix_stride", dec.matrix_stride);
	if (dec.decoration_flags.get(DecorationRowMajor))
	json_stream->emit_json_key_value("row_major", true);

	if (type_is_top_level_physical_pointer(membertype))
	json_stream->emit_json_key_value("physical_pointer", true);
	}
	}

	string CompilerReflection::execution_model_to_str(spv::ExecutionModel model)
	{
	switch (model)
	{
	case ExecutionModelVertex:
	return "vert";
	case ExecutionModelTessellationControl:
	return "tesc";
	case ExecutionModelTessellationEvaluation:
	return "tese";
	case ExecutionModelGeometry:
	return "geom";
	case ExecutionModelFragment:
	return "frag";
	case ExecutionModelGLCompute:
	return "comp";
	case ExecutionModelRayGenerationNV:
	return "rgen";
	case ExecutionModelIntersectionNV:
	return "rint";
	case ExecutionModelAnyHitNV:
	return "rahit";
	case ExecutionModelClosestHitNV:
	return "rchit";
	case ExecutionModelMissNV:
	return "rmiss";
	case ExecutionModelCallableNV:
	return "rcall";
	default:
	return "???";
	}
	}

	// FIXME include things like the local_size dimensions, geometry output vertex count, etc
	void CompilerReflection::emit_entry_points()
	{
	auto entries = get_entry_points_and_stages();
	if (!entries.empty())
	{
	// Needed to make output deterministic.
	sort(begin(entries), end(entries), [](const EntryPoint &a, const EntryPoint &b) -> bool {
	if (a.execution_model < b.execution_model)
	return true;
	else if (a.execution_model > b.execution_model)
	return false;
	else
	return a.name < b.name;
	});

	json_stream->emit_json_key_array("entryPoints");
	for (auto &e : entries)
	{
	json_stream->begin_json_object();
	json_stream->emit_json_key_value("name", e.name);
	json_stream->emit_json_key_value("mode", execution_model_to_str(e.execution_model));
	if (e.execution_model == ExecutionModelGLCompute)
	{
	const auto &spv_entry = get_entry_point(e.name, e.execution_model);

	SpecializationConstant spec_x, spec_y, spec_z;
	get_work_group_size_specialization_constants(spec_x, spec_y, spec_z);

	json_stream->emit_json_key_array("workgroup_size");
	json_stream->emit_json_array_value(spec_x.id != ID(0) ? spec_x.constant_id :
	spv_entry.workgroup_size.x);
	json_stream->emit_json_array_value(spec_y.id != ID(0) ? spec_y.constant_id :
	spv_entry.workgroup_size.y);
	json_stream->emit_json_array_value(spec_z.id != ID(0) ? spec_z.constant_id :
	spv_entry.workgroup_size.z);
	json_stream->end_json_array();

	json_stream->emit_json_key_array("workgroup_size_is_spec_constant_id");
	json_stream->emit_json_array_value(spec_x.id != ID(0));
	json_stream->emit_json_array_value(spec_y.id != ID(0));
	json_stream->emit_json_array_value(spec_z.id != ID(0));
	json_stream->end_json_array();
	}
	json_stream->end_json_object();
	}
	json_stream->end_json_array();
	}
	}

	void CompilerReflection::emit_resources()
	{
	auto res = get_shader_resources();
	emit_resources("subpass_inputs", res.subpass_inputs);
	emit_resources("inputs", res.stage_inputs);
	emit_resources("outputs", res.stage_outputs);
	emit_resources("textures", res.sampled_images);
	emit_resources("separate_images", res.separate_images);
	emit_resources("separate_samplers", res.separate_samplers);
	emit_resources("images", res.storage_images);
	emit_resources("ssbos", res.storage_buffers);
	emit_resources("ubos", res.uniform_buffers);
	emit_resources("push_constants", res.push_constant_buffers);
	emit_resources("counters", res.atomic_counters);
	emit_resources("acceleration_structures", res.acceleration_structures);
	}

	void CompilerReflection::emit_resources(const char *tag, const SmallVector<Resource> &resources)
	{
	if (resources.empty())
	{
	return;
	}

	json_stream->emit_json_key_array(tag);
	for (auto &res : resources)
	{
	auto &type = get_type(res.type_id);
	auto typeflags = ir.meta[type.self].decoration.decoration_flags;
	auto &mask = get_decoration_bitset(res.id);

	// If we don't have a name, use the fallback for the type instead of the variable
	// for SSBOs and UBOs since those are the only meaningful names to use externally.
	// Push constant blocks are still accessed by name and not block name, even though they are technically Blocks.
	bool is_push_constant = get_storage_class(res.id) == StorageClassPushConstant;
	bool is_block = get_decoration_bitset(type.self).get(DecorationBlock) \|\|
	get_decoration_bitset(type.self).get(DecorationBufferBlock);

	ID fallback_id = !is_push_constant && is_block ? ID(res.base_type_id) : ID(res.id);

	json_stream->begin_json_object();

	if (type.basetype == SPIRType::Struct)
	{
	json_stream->emit_json_key_value("type", "_" + std::to_string(res.base_type_id));
	}
	else
	{
	json_stream->emit_json_key_value("type", type_to_glsl(type));
	}

	json_stream->emit_json_key_value("name", !res.name.empty() ? res.name : get_fallback_name(fallback_id));
	{
	bool ssbo_block = type.storage == StorageClassStorageBuffer \|\|
	(type.storage == StorageClassUniform && typeflags.get(DecorationBufferBlock));
	if (ssbo_block)
	{
	auto buffer_flags = get_buffer_block_flags(res.id);
	if (buffer_flags.get(DecorationNonReadable))
	json_stream->emit_json_key_value("writeonly", true);
	if (buffer_flags.get(DecorationNonWritable))
	json_stream->emit_json_key_value("readonly", true);
	if (buffer_flags.get(DecorationRestrict))
	json_stream->emit_json_key_value("restrict", true);
	if (buffer_flags.get(DecorationCoherent))
	json_stream->emit_json_key_value("coherent", true);
	}
	}

	emit_type_array(type);

	{
	bool is_sized_block = is_block && (get_storage_class(res.id) == StorageClassUniform \|\|
	get_storage_class(res.id) == StorageClassUniformConstant \|\|
	get_storage_class(res.id) == StorageClassStorageBuffer);
	if (is_sized_block)
	{
	uint32_t block_size = uint32_t(get_declared_struct_size(get_type(res.base_type_id)));
	json_stream->emit_json_key_value("block_size", block_size);
	}
	}

	if (type.storage == StorageClassPushConstant)
	json_stream->emit_json_key_value("push_constant", true);
	if (mask.get(DecorationLocation))
	json_stream->emit_json_key_value("location", get_decoration(res.id, DecorationLocation));
	if (mask.get(DecorationRowMajor))
	json_stream->emit_json_key_value("row_major", true);
	if (mask.get(DecorationColMajor))
	json_stream->emit_json_key_value("column_major", true);
	if (mask.get(DecorationIndex))
	json_stream->emit_json_key_value("index", get_decoration(res.id, DecorationIndex));
	if (type.storage != StorageClassPushConstant && mask.get(DecorationDescriptorSet))
	json_stream->emit_json_key_value("set", get_decoration(res.id, DecorationDescriptorSet));
	if (mask.get(DecorationBinding))
	json_stream->emit_json_key_value("binding", get_decoration(res.id, DecorationBinding));
	if (mask.get(DecorationInputAttachmentIndex))
	json_stream->emit_json_key_value("input_attachment_index",
	get_decoration(res.id, DecorationInputAttachmentIndex));
	if (mask.get(DecorationOffset))
	json_stream->emit_json_key_value("offset", get_decoration(res.id, DecorationOffset));

	// For images, the type itself adds a layout qualifer.
	// Only emit the format for storage images.
	if (type.basetype == SPIRType::Image && type.image.sampled == 2)
	{
	const char *fmt = format_to_glsl(type.image.format);
	if (fmt != nullptr)
	json_stream->emit_json_key_value("format", std::string(fmt));
	}
	json_stream->end_json_object();
	}
	json_stream->end_json_array();
	}

	void CompilerReflection::emit_specialization_constants()
	{
	auto specialization_constants = get_specialization_constants();
	if (specialization_constants.empty())
	return;

	json_stream->emit_json_key_array("specialization_constants");
	for (const auto &spec_const : specialization_constants)
	{
	auto &c = get<SPIRConstant>(spec_const.id);
	auto type = get<SPIRType>(c.constant_type);
	json_stream->begin_json_object();
	json_stream->emit_json_key_value("name", get_name(spec_const.id));
	json_stream->emit_json_key_value("id", spec_const.constant_id);
	json_stream->emit_json_key_value("type", type_to_glsl(type));
	json_stream->emit_json_key_value("variable_id", spec_const.id);
	switch (type.basetype)
	{
	case SPIRType::UInt:
	json_stream->emit_json_key_value("default_value", c.scalar());
	break;

	case SPIRType::Int:
	json_stream->emit_json_key_value("default_value", c.scalar_i32());
	break;

	case SPIRType::Float:
	json_stream->emit_json_key_value("default_value", c.scalar_f32());
	break;

	case SPIRType::Boolean:
	json_stream->emit_json_key_value("default_value", c.scalar() != 0);
	break;

	default:
	break;
	}
	json_stream->end_json_object();
	}
	json_stream->end_json_array();
	}

	string CompilerReflection::to_member_name(const SPIRType &type, uint32_t index) const
	{
	auto *type_meta = ir.find_meta(type.self);

	if (type_meta)
	{
	auto &memb = type_meta->members;
	if (index < memb.size() && !memb[index].alias.empty())
	return memb[index].alias;
	else
	return join("_m", index);
	}
	else
	return join("_m", index);
	}