bgfx/tools/shaderc/shaderc.cpp

/*
 * Copyright 2011-2024 Branimir Karadzic. All rights reserved.
 * License: https://github.com/bkaradzic/bgfx/blob/master/LICENSE
 */

#include "shaderc.h"
#include <bx/commandline.h>
#include <bx/filepath.h>

#define MAX_TAGS 256
extern "C"
{
#include <fpp.h>
} // extern "C"

#define BGFX_SHADER_BIN_VERSION 11
#define BGFX_CHUNK_MAGIC_CSH BX_MAKEFOURCC('C', 'S', 'H', BGFX_SHADER_BIN_VERSION)
#define BGFX_CHUNK_MAGIC_FSH BX_MAKEFOURCC('F', 'S', 'H', BGFX_SHADER_BIN_VERSION)
#define BGFX_CHUNK_MAGIC_VSH BX_MAKEFOURCC('V', 'S', 'H', BGFX_SHADER_BIN_VERSION)

#define BGFX_SHADERC_VERSION_MAJOR 1
#define BGFX_SHADERC_VERSION_MINOR 18

namespace bgfx
{
	bool g_verbose = false;

	struct ShadingLang
	{
		enum Enum
		{
			ESSL,
			GLSL,
			HLSL,
			Metal,
			PSSL,
			SpirV,

			Count
		};
	};

	static const char* s_shadingLangName[] =
	{
		"OpenGL ES Shading Language / WebGL (ESSL)",
		"OpenGL Shading Language (GLSL)",
		"High-Level Shading Language (HLSL)",
		"Metal Shading Language (MSL)",
		"PlayStation Shader Language (PSSL)",
		"Standard Portable Intermediate Representation - V (SPIR-V)",

		"Unknown?!"
	};
	BX_STATIC_ASSERT(BX_COUNTOF(s_shadingLangName) == ShadingLang::Count+1, "ShadingLang::Enum and s_shadingLangName mismatch");

	const char* getName(ShadingLang::Enum _lang)
	{
		return s_shadingLangName[_lang];
	}

	// c - compute
	// d - domain
	// f - fragment
	// g - geometry
	// h - hull
	// v - vertex
	//
	// OpenGL #version Features Direct3D Features Shader Model
	// 2.1    120      vf       9.0      vf       2.0
	// 3.0    130
	// 3.1    140
	// 3.2    150      vgf
	// 3.3    330               10.0     vgf      4.0
	// 4.0    400      vhdgf
	// 4.1    410
	// 4.2    420               11.0     vhdgf+c  5.0
	// 4.3    430      vhdgf+c
	// 4.4    440
	//
	// Metal Shading Language (MSL) profile naming convention:
	//  metal<MSL version>-<SPIR-V version>
	//
	// See section "Compiler Options Controlling the Language Version" from the
	// MSL spec for the correlation between MSL version and platform OS version:
	//	https://developer.apple.com/metal/Metal-Shading-Language-Specification.pdf
	//
	// MSL version | SPIR-V version | shaderc encoding
	//    1.0      |       1.0      |      1000         (deprecated)
	//    1.1      |       1.0      |      1110
	//    1.2      |       1.0      |      1210
	//    2.0      |       1.1      |      2011
	//    2.1      |       1.1      |      2111
	//    2.2      |       1.1      |      2211
	//    2.3      |       1.4      |      2314
	//    2.4      |       1.4      |      2414
	//    3.0      |       1.4      |      3014
	//    3.1      |       1.4      |      3114
	//
	// SPIR-V profile naming convention:
	//  spirv<SPIR-V version>-<Vulkan version>
	//
	// SPIR-V version | Vulkan version | shaderc encoding
	//       1.0      |       1.0      |      1010
	//       1.3      |       1.1      |      1311
	//       1.4      |       1.1      |      1411
	//       1.5      |       1.2      |      1512
	//       1.6      |       1.3      |      1613

	struct Profile
	{
		ShadingLang::Enum lang;
		uint32_t id;
		const bx::StringLiteral name;
	};

	static const Profile s_profiles[] =
	{
		{  ShadingLang::ESSL,  100,    "100_es"     },
		{  ShadingLang::ESSL,  300,    "300_es"     },
		{  ShadingLang::ESSL,  310,    "310_es"     },
		{  ShadingLang::ESSL,  320,    "320_es"     },
		{  ShadingLang::HLSL,  400,    "s_4_0"      },
		{  ShadingLang::HLSL,  500,    "s_5_0"      },
		{  ShadingLang::Metal, 1210,   "metal"      },
		{  ShadingLang::Metal, 1000,   "metal10-10" },
		{  ShadingLang::Metal, 1110,   "metal11-10" },
		{  ShadingLang::Metal, 1210,   "metal12-10" },
		{  ShadingLang::Metal, 2011,   "metal20-11" },
		{  ShadingLang::Metal, 2111,   "metal21-11" },
		{  ShadingLang::Metal, 2211,   "metal22-11" },
		{  ShadingLang::Metal, 2314,   "metal23-14" },
		{  ShadingLang::Metal, 2414,   "metal24-14" },
		{  ShadingLang::Metal, 3014,   "metal30-14" },
		{  ShadingLang::Metal, 3114,   "metal31-14" },
		{  ShadingLang::PSSL,  1000,   "pssl"       },
		{  ShadingLang::SpirV, 1010,   "spirv"      },
		{  ShadingLang::SpirV, 1010,   "spirv10-10" },
		{  ShadingLang::SpirV, 1311,   "spirv13-11" },
		{  ShadingLang::SpirV, 1411,   "spirv14-11" },
		{  ShadingLang::SpirV, 1512,   "spirv15-12" },
		{  ShadingLang::SpirV, 1613,   "spirv16-13" },
		{  ShadingLang::GLSL,  120,    "120"        },
		{  ShadingLang::GLSL,  130,    "130"        },
		{  ShadingLang::GLSL,  140,    "140"        },
		{  ShadingLang::GLSL,  150,    "150"        },
		{  ShadingLang::GLSL,  330,    "330"        },
		{  ShadingLang::GLSL,  400,    "400"        },
		{  ShadingLang::GLSL,  410,    "410"        },
		{  ShadingLang::GLSL,  420,    "420"        },
		{  ShadingLang::GLSL,  430,    "430"        },
		{  ShadingLang::GLSL,  440,    "440"        },
	};

	static const char* s_ARB_shader_texture_lod[] =
	{
		"texture2DLod",
		"texture2DArrayLod", // BK - interacts with ARB_texture_array.
		"texture2DProjLod",
		"texture2DGrad",
		"texture2DProjGrad",
		"texture3DLod",
		"texture3DProjLod",
		"texture3DGrad",
		"texture3DProjGrad",
		"textureCubeLod",
		"textureCubeGrad",
		"shadow2DLod",
		"shadow2DProjLod",
		NULL
		// "texture1DLod",
		// "texture1DProjLod",
		// "shadow1DLod",
		// "shadow1DProjLod",
	};

	static const char* s_EXT_shader_texture_lod[] =
	{
		"texture2DLod",
		"texture2DProjLod",
		"textureCubeLod",
		"texture2DGrad",
		"texture2DProjGrad",
		"textureCubeGrad",
		NULL
	};

	static const char* s_EXT_shadow_samplers[] =
	{
		"shadow2D",
		"shadow2DProj",
		"sampler2DShadow",
		NULL
	};

	static const char* s_OES_standard_derivatives[] =
	{
		"dFdx",
		"dFdy",
		"fwidth",
		NULL
	};

	static const char* s_OES_texture_3D[] =
	{
		"texture3D",
		"texture3DProj",
		"texture3DLod",
		"texture3DProjLod",
		NULL
	};

	static const char* s_EXT_gpu_shader4[] =
	{
		"gl_VertexID",
		"gl_InstanceID",
		"texture2DLodOffset",
		NULL
	};

	// To be use from vertex program require:
	// https://www.khronos.org/registry/OpenGL/extensions/ARB/ARB_shader_viewport_layer_array.txt
	// DX11 11_1 feature level
	static const char* s_ARB_shader_viewport_layer_array[] =
	{
		"gl_ViewportIndex",
		"gl_Layer",
		NULL
	};

	static const char* s_ARB_gpu_shader5[] =
	{
		"bitfieldReverse",
		"floatBitsToInt",
		"floatBitsToUint",
		"intBitsToFloat",
		"uintBitsToFloat",
		NULL
	};

	static const char* s_ARB_shading_language_packing[] =
	{
		"packHalf2x16",
		"unpackHalf2x16",
		NULL
	};

	static const char* s_130[] =
	{
		"uint",
		"uint2",
		"uint3",
		"uint4",
		"isampler2D",
		"usampler2D",
		"isampler3D",
		"usampler3D",
		"isamplerCube",
		"usamplerCube",
		"textureSize",
		NULL
	};

	static const char* s_textureArray[] =
	{
		"sampler2DArray",
		"texture2DArray",
		"texture2DArrayLod",
		"shadow2DArray",
		NULL
	};

	static const char* s_ARB_texture_multisample[] =
	{
		"sampler2DMS",
		"isampler2DMS",
		"usampler2DMS",
		NULL
	};

	static const char* s_texelFetch[] =
	{
		"texelFetch",
		"texelFetchOffset",
		NULL
	};

	static const char* s_bitsToEncoders[] =
	{
		"floatBitsToUint",
		"floatBitsToInt",
		"intBitsToFloat",
		"uintBitsToFloat",
		NULL
	};

	static const char* s_unsignedVecs[] =
	{
		"uvec2",
		"uvec3",
		"uvec4",
		NULL
	};

	const char* s_uniformTypeName[] =
	{
		"int",  "int",
		NULL,   NULL,
		"vec4", "float4",
		"mat3", "float3x3",
		"mat4", "float4x4",
	};
	BX_STATIC_ASSERT(BX_COUNTOF(s_uniformTypeName) == UniformType::Count*2);

	static const char* s_allowedVertexShaderInputs[] =
	{
		"a_position",
		"a_normal",
		"a_tangent",
		"a_bitangent",
		"a_color0",
		"a_color1",
		"a_color2",
		"a_color3",
		"a_indices",
		"a_weight",
		"a_texcoord0",
		"a_texcoord1",
		"a_texcoord2",
		"a_texcoord3",
		"a_texcoord4",
		"a_texcoord5",
		"a_texcoord6",
		"a_texcoord7",
		"i_data0",
		"i_data1",
		"i_data2",
		"i_data3",
		"i_data4",
		NULL
	};

	void fatal(const char* _filePath, uint16_t _line, Fatal::Enum _code, const char* _format, ...)
	{
		BX_UNUSED(_filePath, _line, _code);

		va_list argList;
		va_start(argList, _format);

		bx::vprintf(_format, argList);

		va_end(argList);

		abort();
	}

	void trace(const char* _filePath, uint16_t _line, const char* _format, ...)
	{
		BX_UNUSED(_filePath, _line);

		va_list argList;
		va_start(argList, _format);

		bx::vprintf(_format, argList);

		va_end(argList);
	}
	Options::Options()
		: shaderType(' ')
		, disasm(false)
		, raw(false)
		, preprocessOnly(false)
		, depends(false)
		, debugInformation(false)
		, avoidFlowControl(false)
		, noPreshader(false)
		, partialPrecision(false)
		, preferFlowControl(false)
		, backwardsCompatibility(false)
		, warningsAreErrors(false)
		, keepIntermediate(false)
		, optimize(false)
		, optimizationLevel(3)
	{
	}

	void Options::dump()
	{
		BX_TRACE("Options:\n"
			"\t  shaderType: %c\n"
			"\t  platform: %s\n"
			"\t  profile: %s\n"
			"\t  inputFile: %s\n"
			"\t  outputFile: %s\n"
			"\t  disasm: %s\n"
			"\t  raw: %s\n"
			"\t  preprocessOnly: %s\n"
			"\t  depends: %s\n"
			"\t  debugInformation: %s\n"
			"\t  avoidFlowControl: %s\n"
			"\t  noPreshader: %s\n"
			"\t  partialPrecision: %s\n"
			"\t  preferFlowControl: %s\n"
			"\t  backwardsCompatibility: %s\n"
			"\t  warningsAreErrors: %s\n"
			"\t  keepIntermediate: %s\n"
			"\t  optimize: %s\n"
			"\t  optimizationLevel: %d\n"

			, shaderType
			, platform.c_str()
			, profile.c_str()
			, inputFilePath.c_str()
			, outputFilePath.c_str()
			, disasm ? "true" : "false"
			, raw ? "true" : "false"
			, preprocessOnly ? "true" : "false"
			, depends ? "true" : "false"
			, debugInformation ? "true" : "false"
			, avoidFlowControl ? "true" : "false"
			, noPreshader ? "true" : "false"
			, partialPrecision ? "true" : "false"
			, preferFlowControl ? "true" : "false"
			, backwardsCompatibility ? "true" : "false"
			, warningsAreErrors ? "true" : "false"
			, keepIntermediate ? "true" : "false"
			, optimize ? "true" : "false"
			, optimizationLevel
			);

		for (size_t ii = 0; ii < includeDirs.size(); ++ii)
		{
			BX_TRACE("\t  include :%s\n", includeDirs[ii].c_str() );
		}

		for (size_t ii = 0; ii < defines.size(); ++ii)
		{
			BX_TRACE("\t  define :%s\n", defines[ii].c_str() );
		}

		for (size_t ii = 0; ii < dependencies.size(); ++ii)
		{
			BX_TRACE("\t  dependency :%s\n", dependencies[ii].c_str() );
		}
	}

	const char* interpolationDx11(const char* _glsl)
	{
		if (0 == bx::strCmp(_glsl, "smooth") )
		{
			return "linear";
		}
		else if (0 == bx::strCmp(_glsl, "flat") )
		{
			return "nointerpolation";
		}

		return _glsl; // centroid, noperspective
	}

	const char* getUniformTypeName(UniformType::Enum _enum)
	{
		uint32_t idx = _enum & ~(kUniformFragmentBit|kUniformSamplerBit);
		if (idx < UniformType::Count)
		{
			return s_uniformTypeName[idx];
		}

		return "Unknown uniform type?!";
	}

	UniformType::Enum nameToUniformTypeEnum(const char* _name)
	{
		for (uint32_t ii = 0; ii < UniformType::Count*2; ++ii)
		{
			if (NULL != s_uniformTypeName[ii]
			&&  0 == bx::strCmp(_name, s_uniformTypeName[ii]) )
			{
				return UniformType::Enum(ii/2);
			}
		}

		return UniformType::Count;
	}

	int32_t writef(bx::WriterI* _writer, const char* _format, ...)
	{
		va_list argList;
		va_start(argList, _format);

		char temp[2048];

		char* out = temp;
		int32_t max = sizeof(temp);
		int32_t len = bx::vsnprintf(out, max, _format, argList);
		if (len > max)
		{
			out = (char*)alloca(len);
			len = bx::vsnprintf(out, len, _format, argList);
		}

		len = bx::write(_writer, out, len, bx::ErrorAssert{});

		va_end(argList);

		return len;
	}

	class Bin2cWriter : public bx::FileWriter
	{
	public:
		Bin2cWriter(const bx::StringView& _name)
			: m_name(_name)
		{
		}

		virtual ~Bin2cWriter()
		{
		}

		virtual void close() override
		{
			generate();
			return bx::FileWriter::close();
		}

		virtual int32_t write(const void* _data, int32_t _size, bx::Error*) override
		{
			const char* data = (const char*)_data;
			m_buffer.insert(m_buffer.end(), data, data+_size);
			return _size;
		}

	private:
		void generate()
		{
#define HEX_DUMP_WIDTH 16
#define HEX_DUMP_SPACE_WIDTH 96
#define HEX_DUMP_FORMAT "%-" BX_STRINGIZE(HEX_DUMP_SPACE_WIDTH) "." BX_STRINGIZE(HEX_DUMP_SPACE_WIDTH) "s"
			const uint8_t* data = &m_buffer[0];
			uint32_t size = (uint32_t)m_buffer.size();

			outf("static const uint8_t %.*s[%d] =\n{\n", m_name.getLength(), m_name.getPtr(), size);

			if (NULL != data)
			{
				char hex[HEX_DUMP_SPACE_WIDTH+1];
				char ascii[HEX_DUMP_WIDTH+1];
				uint32_t hexPos = 0;
				uint32_t asciiPos = 0;
				for (uint32_t ii = 0; ii < size; ++ii)
				{
					bx::snprintf(&hex[hexPos], sizeof(hex)-hexPos, "0x%02x, ", data[asciiPos]);
					hexPos += 6;

					ascii[asciiPos] = isprint(data[asciiPos]) && data[asciiPos] != '\\'  && data[asciiPos] != '\t' ? data[asciiPos] : '.';
					asciiPos++;

					if (HEX_DUMP_WIDTH == asciiPos)
					{
						ascii[asciiPos] = '\0';
						outf("\t" HEX_DUMP_FORMAT "// %s\n", hex, ascii);
						data += asciiPos;
						hexPos = 0;
						asciiPos = 0;
					}
				}

				if (0 != asciiPos)
				{
					ascii[asciiPos] = '\0';
					outf("\t" HEX_DUMP_FORMAT "// %s\n", hex, ascii);
				}
			}

			outf("};\n");
#undef HEX_DUMP_WIDTH
#undef HEX_DUMP_SPACE_WIDTH
#undef HEX_DUMP_FORMAT
		}

		int32_t outf(const char* _format, ...)
		{
			va_list argList;
			va_start(argList, _format);

			char temp[2048];
			char* out = temp;
			int32_t max = sizeof(temp);
			int32_t len = bx::vsnprintf(out, max, _format, argList);
			if (len > max)
			{
				out = (char*)alloca(len);
				len = bx::vsnprintf(out, len, _format, argList);
			}

			int32_t size = bx::FileWriter::write(out, len, bx::ErrorAssert{});

			va_end(argList);

			return size;
		}

		bx::StringView m_name;
		typedef std::vector<uint8_t> Buffer;
		Buffer m_buffer;
	};

	struct Varying
	{
		std::string m_precision;
		std::string m_interpolation;
		std::string m_name;
		std::string m_type;
		std::string m_init;
		std::string m_semantics;
	};

	typedef std::unordered_map<std::string, Varying> VaryingMap;

	class File
	{
	public:
		File()
			: m_data(NULL)
			, m_size(0)
		{
		}

		~File()
		{
			delete [] m_data;
		}

		void load(const bx::FilePath& _filePath)
		{
			bx::FileReader reader;
			if (bx::open(&reader, _filePath) )
			{
				m_size = (uint32_t)bx::getSize(&reader);
				m_data = new char[m_size+1];
				m_size = (uint32_t)bx::read(&reader, m_data, m_size, bx::ErrorAssert{});
				bx::close(&reader);

				if (m_data[0] == '\xef'
				&&  m_data[1] == '\xbb'
				&&  m_data[2] == '\xbf')
				{
					bx::memMove(m_data, &m_data[3], m_size-3);
					m_size -= 3;
				}

				m_data[m_size] = '\0';
			}
		}

		const char* getData() const
		{
			return m_data;
		}

		uint32_t getSize() const
		{
			return m_size;
		}

	private:
		char* m_data;
		uint32_t m_size;
	};

	char* strInsert(char* _str, const char* _insert)
	{
		uint32_t len = bx::strLen(_insert);
		bx::memMove(&_str[len], _str, bx::strLen(_str) );
		bx::memCopy(_str, _insert, len);
		return _str + len;
	}

	void strReplace(char* _str, const char* _find, const char* _replace)
	{
		const int32_t len = bx::strLen(_find);

		char* replace = (char*)alloca(len+1);
		bx::strCopy(replace, len+1, _replace);
		for (int32_t ii = bx::strLen(replace); ii < len; ++ii)
		{
			replace[ii] = ' ';
		}
		replace[len] = '\0';

		BX_ASSERT(len >= bx::strLen(_replace), "");
		for (bx::StringView ptr = bx::strFind(_str, _find)
			; !ptr.isEmpty()
			; ptr = bx::strFind(ptr.getPtr() + len, _find)
			)
		{
			bx::memCopy(const_cast<char*>(ptr.getPtr() ), replace, len);
		}
	}

	void strNormalizeEol(char* _str)
	{
		strReplace(_str, "\r\n", "\n");
		strReplace(_str, "\r",   "\n");
	}

	void printCode(const char* _code, int32_t _line, int32_t _start, int32_t _end, int32_t _column)
	{
		bx::printf("Code:\n---\n");

		bx::LineReader reader(_code);
		for (int32_t line = 1; !reader.isDone() && line < _end; ++line)
		{
			bx::StringView strLine = reader.next();

			if (line >= _start)
			{
				if (_line == line)
				{
					bx::printf("\n");
					bx::printf(">>> %3d: %.*s\n", line, strLine.getLength(), strLine.getPtr() );
					if (-1 != _column)
					{
						bx::printf(">>> %3d: %*s\n", _column, _column, "^");
					}
					bx::printf("\n");
				}
				else
				{
					bx::printf("    %3d: %.*s\n", line, strLine.getLength(), strLine.getPtr() );
				}
			}
		}

		bx::printf("---\n");
	}

	void writeFile(const char* _filePath, const void* _data, int32_t _size)
	{
		bx::FileWriter out;
		if (bx::open(&out, _filePath) )
		{
			bx::write(&out, _data, _size, bx::ErrorAssert{});
			bx::close(&out);
		}
	}

	struct Preprocessor
	{
		Preprocessor(const char* _filePath, bool _essl, bx::WriterI* _messageWriter)
			: m_tagptr(m_tags)
			, m_scratchPos(0)
			, m_fgetsPos(0)
			, m_messageWriter(_messageWriter)
		{
			m_tagptr->tag = FPPTAG_USERDATA;
			m_tagptr->data = this;
			m_tagptr++;

			m_tagptr->tag = FPPTAG_DEPENDS;
			m_tagptr->data = (void*)fppDepends;
			m_tagptr++;

			m_tagptr->tag = FPPTAG_INPUT;
			m_tagptr->data = (void*)fppInput;
			m_tagptr++;

			m_tagptr->tag = FPPTAG_OUTPUT;
			m_tagptr->data = (void*)fppOutput;
			m_tagptr++;

			m_tagptr->tag = FPPTAG_ERROR;
			m_tagptr->data = (void*)fppError;
			m_tagptr++;

			m_tagptr->tag = FPPTAG_SHOWVERSION;
			m_tagptr->data = (void*)0;
			m_tagptr++;

			m_tagptr->tag = FPPTAG_LINE;
			m_tagptr->data = (void*)0;
			m_tagptr++;

			m_tagptr->tag = FPPTAG_INPUT_NAME;
			m_tagptr->data = scratch(_filePath);
			m_tagptr++;

			if (!_essl)
			{
				m_default = "#define lowp\n#define mediump\n#define highp\n";
			}
		}

		void setDefine(const char* _define)
		{
			m_tagptr->tag = FPPTAG_DEFINE;
			m_tagptr->data = scratch(_define);
			m_tagptr++;
		}

		void setDefaultDefine(const char* _name)
		{
			char temp[1024];
			bx::snprintf(temp, BX_COUNTOF(temp)
				, "#ifndef %s\n"
				  "#	define %s 0\n"
				  "#endif // %s\n"
				  "\n"
				, _name
				, _name
				, _name
				);

			m_default += temp;
		}

		void writef(const char* _format, ...)
		{
			va_list argList;
			va_start(argList, _format);
			bx::stringPrintfVargs(m_default, _format, argList);
			va_end(argList);
		}

		void addInclude(const char* _includeDir)
		{
			char* start = scratch(_includeDir);

			for (bx::StringView split = bx::strFind(start, ';')
				; !split.isEmpty()
				; split = bx::strFind(start, ';')
				)
			{
				*const_cast<char*>(split.getPtr() ) = '\0';
				m_tagptr->tag = FPPTAG_INCLUDE_DIR;
				m_tagptr->data = start;
				m_tagptr++;
				start = const_cast<char*>(split.getPtr() ) + 1;
			}

			m_tagptr->tag = FPPTAG_INCLUDE_DIR;
			m_tagptr->data = start;
			m_tagptr++;
		}

		void addDependency(const char* _fileName)
		{
			m_depends += " \\\n ";
			m_depends += _fileName;
		}

		bool run(const char* _input)
		{
			m_fgetsPos = 0;

			m_preprocessed.clear();
			m_input = m_default;
			m_input += "\n\n";

			int32_t len = bx::strLen(_input)+1;
			char* temp = new char[len];
			bx::StringView normalized = bx::normalizeEolLf(temp, len, _input);
			std::string str;
			str.assign(normalized.getPtr(), normalized.getTerm() );
			m_input += str;
			delete [] temp;

			fppTag* tagptr = m_tagptr;

			tagptr->tag = FPPTAG_END;
			tagptr->data = 0;
			tagptr++;

			int result = fppPreProcess(m_tags);

			return 0 == result;
		}

		char* fgets(char* _buffer, int _size)
		{
			int ii = 0;
			for (char ch = m_input[m_fgetsPos]; m_fgetsPos < m_input.size() && ii < _size-1; ch = m_input[++m_fgetsPos])
			{
				_buffer[ii++] = ch;

				if (ch == '\n' || ii == _size)
				{
					_buffer[ii] = '\0';
					m_fgetsPos++;
					return _buffer;
				}
			}

			return NULL;
		}

		static void fppDepends(char* _fileName, void* _userData)
		{
			Preprocessor* thisClass = (Preprocessor*)_userData;
			thisClass->addDependency(_fileName);
		}

		static char* fppInput(char* _buffer, int _size, void* _userData)
		{
			Preprocessor* thisClass = (Preprocessor*)_userData;
			return thisClass->fgets(_buffer, _size);
		}

		static void fppOutput(int _ch, void* _userData)
		{
			Preprocessor* thisClass = (Preprocessor*)_userData;
			thisClass->m_preprocessed += char(_ch);
		}

		static void fppError(void* _userData, char* _format, va_list _vargs)
		{
			bx::ErrorAssert err;
			Preprocessor* thisClass = (Preprocessor*)_userData;
			bx::write(thisClass->m_messageWriter, _format, _vargs, &err);
		}

		char* scratch(const char* _str)
		{
			char* result = &m_scratch[m_scratchPos];
			bx::strCopy(result, uint32_t(sizeof(m_scratch)-m_scratchPos), _str);
			m_scratchPos += (uint32_t)bx::strLen(_str)+1;

			return result;
		}

		fppTag m_tags[MAX_TAGS];
		fppTag* m_tagptr;

		std::string m_depends;
		std::string m_default;
		std::string m_input;
		std::string m_preprocessed;
		char m_scratch[16<<10];
		uint32_t m_scratchPos;
		uint32_t m_fgetsPos;
		bx::WriterI* m_messageWriter;
	};

	typedef std::vector<std::string> InOut;

	uint32_t parseInOut(InOut& _inout, const bx::StringView& _str)
	{
		uint32_t hash = 0;
		bx::StringView str = bx::strLTrimSpace(_str);

		if (!str.isEmpty() )
		{
			bx::StringView delim;
			do
			{
				delim = bx::strFind(str, ',');
				if (delim.isEmpty() )
				{
					delim = bx::strFind(str, ' ');
				}

				const bx::StringView token(bx::strRTrim(bx::StringView(str.getPtr(), delim.getPtr() ), " ") );

				if (!token.isEmpty() )
				{
					_inout.push_back(std::string(token.getPtr(), token.getTerm() ) );
					str = bx::strLTrimSpace(bx::StringView(delim.getPtr() + 1, str.getTerm() ) );
				}
			}
			while (!delim.isEmpty() );

			std::sort(_inout.begin(), _inout.end() );

			bx::HashMurmur2A murmur;
			murmur.begin();
			for (InOut::const_iterator it = _inout.begin(), itEnd = _inout.end(); it != itEnd; ++it)
			{
				murmur.add(it->c_str(), (uint32_t)it->size() );
			}
			hash = murmur.end();
		}

		return hash;
	}

	void addFragData(Preprocessor& _preprocessor, char* _data, uint32_t _idx, bool _comma)
	{
		char find[32];
		bx::snprintf(find, sizeof(find), "gl_FragData[%d]", _idx);

		char replace[32];
		bx::snprintf(replace, sizeof(replace), "bgfx_FragData%d", _idx);

		strReplace(_data, find, replace);

		_preprocessor.writef(
			" \\\n\t%sout vec4 bgfx_FragData%d : SV_TARGET%d"
			, _comma ? ", " : "  "
			, _idx
			, _idx
			);
	}

	void voidFragData(char* _data, uint32_t _idx)
	{
		char find[32];
		bx::snprintf(find, sizeof(find), "gl_FragData[%d]", _idx);

		strReplace(_data, find, "bgfx_VoidFrag");
	}

	bx::StringView baseName(const bx::StringView& _filePath)
	{
		bx::FilePath fp(_filePath);
		return bx::strFind(_filePath, fp.getBaseName() );
	}

	void help(const char* _error = NULL)
	{
		if (NULL != _error)
		{
			bx::printf("Error:\n%s\n\n", _error);
		}

		bx::printf(
			  "shaderc, bgfx shader compiler tool, version %d.%d.%d.\n"
			  "Copyright 2011-2024 Branimir Karadzic. All rights reserved.\n"
			  "License: https://github.com/bkaradzic/bgfx/blob/master/LICENSE\n\n"
			, BGFX_SHADERC_VERSION_MAJOR
			, BGFX_SHADERC_VERSION_MINOR
			, BGFX_API_VERSION
			);

		bx::printf(
			  "Usage: shaderc -f <in> -o <out> --type <v/f/c> --platform <platform>\n"

			  "\n"
			  "Options:\n"
			  "  -h, --help                    Display this help and exit.\n"
			  "  -v, --version                 Output version information and exit.\n"
			  "  -f <file path>                Input's file path.\n"
			  "  -i <include path>             Include path. (for multiple paths use -i multiple times)\n"
			  "  -o <file path>                Output's file path.\n"
			  "      --stdout                  Output to console.\n"
			  "      --bin2c [array name]      Generate C header file. If array name is not specified base file name will be used as name.\n"
			  "      --depends                 Generate makefile style depends file.\n"
			  "      --platform <platform>     Target platform.\n"
			  "           android\n"
			  "           asm.js\n"
			  "           ios\n"
			  "           linux\n"
			  "           orbis\n"
			  "           osx\n"
			  "           windows\n"
			  "      -p, --profile <profile>   Shader model. Defaults to GLSL.\n"
			);

		{
			ShadingLang::Enum lang = ShadingLang::Count;
			for (uint32_t ii = 0; ii < BX_COUNTOF(s_profiles); ++ii)
			{
				const Profile& profile = s_profiles[ii];
				if (lang != profile.lang)
				{
					lang = profile.lang;
					bx::printf("\n");
					bx::printf("           %-20S %s\n", &profile.name, getName(profile.lang) );
				}
				else
				{
					bx::printf("           %S\n", &profile.name);
				}

			}
		}

		bx::printf(
			  "      --preprocess              Only pre-process.\n"
			  "      --define <defines>        Add defines to preprocessor. (Semicolon-separated)\n"
			  "      --raw                     Do not process shader. No preprocessor, and no glsl-optimizer. (GLSL only)\n"
			  "      --type <type>             Shader type. Can be 'vertex', 'fragment, or 'compute'.\n"
			  "      --varyingdef <file path>  varying.def.sc's file path.\n"
			  "      --verbose                 Be verbose.\n"

			  "\n"
			  "(Vulkan, DirectX and Metal):\n"

			  "\n"
			  "      --debug                   Debug information.\n"

			  "\n"
			  "(DirectX only):\n"

			  "\n"
			  "      --disasm                  Disassemble compiled shader.\n"
			  "  -O <level>                    Set optimization level. Can be 0 to 3.\n"
			  "      --Werror                  Treat warnings as errors.\n"

			  "\n"
			  "For additional information, see https://github.com/bkaradzic/bgfx\n"
			);
	}

	bx::StringView nextWord(bx::StringView& _parse)
	{
		bx::StringView word = bx::strWord(bx::strLTrimSpace(_parse) );
		_parse = bx::strLTrimSpace(bx::StringView(word.getTerm(), _parse.getTerm() ) );
		return word;
	}

	bool compileShader(const char* _varying, const char* _comment, char* _shader, uint32_t _shaderLen, const Options& _options, bx::WriterI* _shaderWriter, bx::WriterI* _messageWriter)
	{
		bx::ErrorAssert messageErr;

		uint32_t profileId = 0;

		const bx::StringView profileOpt(_options.profile.c_str() );
		if (!profileOpt.isEmpty() )
		{
			const uint32_t count = BX_COUNTOF(s_profiles);
			for (profileId = 0; profileId < count; ++profileId)
			{
				if (0 == bx::strCmp(profileOpt, s_profiles[profileId].name) )
				{
					break;
				}
			}

			if (profileId == count)
			{
				bx::write(_messageWriter, &messageErr, "Unknown profile: %S\n", &profileOpt);
				return false;
			}
		}
		else
		{
			bx::write(_messageWriter, &messageErr, "Shader profile must be specified.\n");
			return false;
		}

		const Profile* profile = &s_profiles[profileId];

		Preprocessor preprocessor(_options.inputFilePath.c_str(), profile->lang == ShadingLang::ESSL, _messageWriter);

		for (size_t ii = 0; ii < _options.includeDirs.size(); ++ii)
		{
			preprocessor.addInclude(_options.includeDirs[ii].c_str() );
		}

		for (size_t ii = 0; ii < _options.defines.size(); ++ii)
		{
			preprocessor.setDefine(_options.defines[ii].c_str() );
		}

		for (size_t ii = 0; ii < _options.dependencies.size(); ++ii)
		{
			preprocessor.addDependency(_options.dependencies[ii].c_str() );
		}

		preprocessor.setDefaultDefine("BX_PLATFORM_ANDROID");
		preprocessor.setDefaultDefine("BX_PLATFORM_EMSCRIPTEN");
		preprocessor.setDefaultDefine("BX_PLATFORM_IOS");
		preprocessor.setDefaultDefine("BX_PLATFORM_LINUX");
		preprocessor.setDefaultDefine("BX_PLATFORM_OSX");
		preprocessor.setDefaultDefine("BX_PLATFORM_PS4");
		preprocessor.setDefaultDefine("BX_PLATFORM_WINDOWS");
		preprocessor.setDefaultDefine("BX_PLATFORM_XBOXONE");

		preprocessor.setDefaultDefine("BGFX_SHADER_LANGUAGE_GLSL");
		preprocessor.setDefaultDefine("BGFX_SHADER_LANGUAGE_HLSL");
		preprocessor.setDefaultDefine("BGFX_SHADER_LANGUAGE_METAL");
		preprocessor.setDefaultDefine("BGFX_SHADER_LANGUAGE_PSSL");
		preprocessor.setDefaultDefine("BGFX_SHADER_LANGUAGE_SPIRV");

		preprocessor.setDefaultDefine("BGFX_SHADER_TYPE_COMPUTE");
		preprocessor.setDefaultDefine("BGFX_SHADER_TYPE_FRAGMENT");
		preprocessor.setDefaultDefine("BGFX_SHADER_TYPE_VERTEX");

		char glslDefine[128];
		if (profile->lang == ShadingLang::GLSL
		||  profile->lang == ShadingLang::ESSL)
		{
			bx::snprintf(glslDefine, BX_COUNTOF(glslDefine)
				, "BGFX_SHADER_LANGUAGE_GLSL=%d"
				, profile->id
				);
		}

		char hlslDefine[128];
		if (profile->lang == ShadingLang::HLSL)
		{
			bx::snprintf(hlslDefine, BX_COUNTOF(hlslDefine)
				, "BGFX_SHADER_LANGUAGE_HLSL=%d"
				, profile->id);
		}

		const char* platform = _options.platform.c_str();

		if (0 == bx::strCmpI(platform, "android") )
		{
			preprocessor.setDefine("BX_PLATFORM_ANDROID=1");
			if (profile->lang == ShadingLang::SpirV)
			{
				preprocessor.setDefine("BGFX_SHADER_LANGUAGE_SPIRV=1");
			}
			else
			{
				preprocessor.setDefine(glslDefine);
			}
		}
		else if (0 == bx::strCmpI(platform, "asm.js") )
		{
			preprocessor.setDefine("BX_PLATFORM_EMSCRIPTEN=1");
			preprocessor.setDefine(glslDefine);
		}
		else if (0 == bx::strCmpI(platform, "linux") )
		{
			preprocessor.setDefine("BX_PLATFORM_LINUX=1");
			if (profile->lang == ShadingLang::SpirV)
			{
				preprocessor.setDefine("BGFX_SHADER_LANGUAGE_SPIRV=1");
			}
			else
			{
				preprocessor.setDefine(glslDefine);
			}
		}
		else if (0 == bx::strCmpI(platform, "ios") || (0 == bx::strCmpI(platform, "osx")) )
		{
			if (0 == bx::strCmpI(platform, "osx"))
			{
				preprocessor.setDefine("BX_PLATFORM_OSX=1");
			}
			else
			{
				preprocessor.setDefine("BX_PLATFORM_IOS=1");
			}

			if (profile->lang != ShadingLang::Metal)
			{
				preprocessor.setDefine(glslDefine);
			}
			char temp[32];
			bx::snprintf(
				temp
				, sizeof(temp)
				, "BGFX_SHADER_LANGUAGE_METAL=%d"
				, (profile->lang == ShadingLang::Metal) ? profile->id : 0
			);
			preprocessor.setDefine(temp);
		}
		else if (0 == bx::strCmpI(platform, "windows") )
		{
			preprocessor.setDefine("BX_PLATFORM_WINDOWS=1");
			if (profile->lang == ShadingLang::HLSL)
			{
				preprocessor.setDefine(hlslDefine);
			}
			else if (profile->lang == ShadingLang::GLSL
			     ||  profile->lang == ShadingLang::ESSL)
			{
				preprocessor.setDefine(glslDefine);
			}
			else if (profile->lang == ShadingLang::SpirV)
			{
				preprocessor.setDefine("BGFX_SHADER_LANGUAGE_SPIRV=1");
			}
		}
		else if (0 == bx::strCmpI(platform, "orbis") )
		{
			preprocessor.setDefine("BX_PLATFORM_PS4=1");
			preprocessor.setDefine("BGFX_SHADER_LANGUAGE_PSSL=1");
			preprocessor.setDefine("lit=lit_reserved");
		}
		else
		{
			if (profile->lang == ShadingLang::HLSL)
			{
				preprocessor.setDefine(hlslDefine);
			}
			else if (profile->lang == ShadingLang::GLSL
			     ||  profile->lang == ShadingLang::ESSL)
			{
				preprocessor.setDefine(glslDefine);
			}
			else if (profile->lang == ShadingLang::SpirV)
			{
				preprocessor.setDefine("BGFX_SHADER_LANGUAGE_SPIRV=1");
			}
		}

		preprocessor.setDefine("M_PI=3.1415926535897932384626433832795");

		switch (_options.shaderType)
		{
		case 'c':
			preprocessor.setDefine("BGFX_SHADER_TYPE_COMPUTE=1");
			break;

		case 'f':
			preprocessor.setDefine("BGFX_SHADER_TYPE_FRAGMENT=1");
			break;

		case 'v':
			preprocessor.setDefine("BGFX_SHADER_TYPE_VERTEX=1");
			break;

		default:
			bx::write(_messageWriter, &messageErr, "Unknown type: %c?!", _options.shaderType);
			return false;
		}

		bool compiled = false;

		VaryingMap varyingMap;
		bx::StringView parse(_varying);
		bx::StringView term(parse);

		bool usesInterpolationQualifiers = false;

		while (!parse.isEmpty() )
		{
			parse = bx::strLTrimSpace(parse);
			bx::StringView eol = bx::strFind(parse, ';');
			if (eol.isEmpty() )
			{
				eol = bx::strFindEol(parse);
			}

			if (!eol.isEmpty() )
			{
				eol.set(eol.getPtr() + 1, parse.getTerm() );

				bx::StringView precision;
				bx::StringView interpolation;
				bx::StringView typen = nextWord(parse);

				if (0 == bx::strCmp(typen, "lowp", 4)
				||  0 == bx::strCmp(typen, "mediump", 7)
				||  0 == bx::strCmp(typen, "highp", 5) )
				{
					precision = typen;
					typen = nextWord(parse);
				}

				if (0 == bx::strCmp(typen, "flat", 4)
				||  0 == bx::strCmp(typen, "smooth", 6)
				||  0 == bx::strCmp(typen, "noperspective", 13)
				||  0 == bx::strCmp(typen, "centroid", 8) )
				{
					if ('f' == _options.shaderType
					||   profile->lang == ShadingLang::GLSL
					||   profile->lang == ShadingLang::ESSL)
					{
						interpolation = typen;
						usesInterpolationQualifiers = true;
					}

					typen = nextWord(parse);
				}

				bx::StringView name   = nextWord(parse);
				bx::StringView column = bx::strSubstr(parse, 0, 1);
				bx::StringView semantics;
				if (0 == bx::strCmp(column, ":", 1) )
				{
					parse = bx::strLTrimSpace(bx::StringView(parse.getPtr() + 1, parse.getTerm() ) );
					semantics = nextWord(parse);
				}

				bx::StringView assign = bx::strSubstr(parse, 0, 1);
				bx::StringView init;
				if (0 == bx::strCmp(assign, "=", 1) )
				{
					parse = bx::strLTrimSpace(bx::StringView(parse.getPtr() + 1, parse.getTerm() ) );
					init.set(parse.getPtr(), eol.getPtr() );
				}

				if (!typen.isEmpty()
				&&  !name.isEmpty()
				&&  !semantics.isEmpty() )
				{
					Varying var;
					if (!precision.isEmpty() )
					{
						var.m_precision.assign(precision.getPtr(), precision.getTerm() );
					}

					if (!interpolation.isEmpty() )
					{
						var.m_interpolation.assign(interpolation.getPtr(), interpolation.getTerm() );
					}

					var.m_type.assign(typen.getPtr(), typen.getTerm() );
					var.m_name.assign(name.getPtr(), name.getTerm() );
					var.m_semantics.assign(semantics.getPtr(), semantics.getTerm() );

					if (profile->lang == ShadingLang::HLSL
					&&  profile->id < 400
					&&  var.m_semantics == "BITANGENT")
					{
						var.m_semantics = "BINORMAL";
					}

					if (!init.isEmpty() )
					{
						var.m_init.assign(init.getPtr(), init.getTerm() );
					}

					varyingMap.insert(std::make_pair(var.m_name, var) );
				}

				parse = bx::strLTrimSpace(bx::strFindNl(bx::StringView(eol.getPtr(), term.getTerm() ) ) );
			}
		}

		bool raw = _options.raw;

		InOut shaderInputs;
		InOut shaderOutputs;
		uint32_t inputHash = 0;
		uint32_t outputHash = 0;
		bx::ErrorAssert err;

		char* data;
		char* input;
		{
			data = _shader;
			uint32_t size = _shaderLen;

			const size_t padding = 16384;

			if (!raw)
			{
				// To avoid commented code being recognized as used feature,
				// first preprocess pass is used to strip all comments before
				// substituting code.
				bool ok = preprocessor.run(data);
				delete [] data;

				if (!ok)
				{
					return false;
				}

				size = (uint32_t)preprocessor.m_preprocessed.size();
				data = new char[size+padding+1];
				bx::memCopy(data, preprocessor.m_preprocessed.c_str(), size);
				bx::memSet(&data[size], 0, padding+1);
			}

			strNormalizeEol(data);

			input = const_cast<char*>(bx::strLTrimSpace(data).getPtr() );
			while (input[0] == '$')
			{
				bx::StringView str = bx::strLTrimSpace(input+1);
				bx::StringView eol = bx::strFindEol(str);
				bx::StringView nl  = bx::strFindNl(eol);
				input = const_cast<char*>(nl.getPtr() );

				if (0 == bx::strCmp(str, "input", 5) )
				{
					str = bx::StringView(str.getPtr() + 5, str.getTerm() );
					bx::StringView comment = bx::strFind(str, "//");
					eol = !comment.isEmpty() && comment.getPtr() < eol.getPtr() ? comment.getPtr() : eol;
					inputHash = parseInOut(shaderInputs, bx::StringView(str.getPtr(), eol.getPtr() ) );
				}
				else if (0 == bx::strCmp(str, "output", 6) )
				{
					str = bx::StringView(str.getPtr() + 6, str.getTerm() );
					bx::StringView comment = bx::strFind(str, "//");
					eol = !comment.isEmpty() && comment.getPtr() < eol.getPtr() ? comment.getPtr() : eol;
					outputHash = parseInOut(shaderOutputs, bx::StringView(str.getPtr(), eol.getPtr() ) );
				}
				else if (0 == bx::strCmp(str, "raw", 3) )
				{
					raw = true;
					str = bx::StringView(str.getPtr() + 3, str.getTerm() );
				}

				input = const_cast<char*>(bx::strLTrimSpace(input).getPtr() );
			}
		}

		bool invalidShaderAttribute = false;
		if ('v' == _options.shaderType)
		{
			for (InOut::const_iterator it = shaderInputs.begin(), itEnd = shaderInputs.end(); it != itEnd; ++it)
			{
				if (bx::findIdentifierMatch(it->c_str(), s_allowedVertexShaderInputs).isEmpty() )
				{
					invalidShaderAttribute = true;
					bx::write(_messageWriter, &messageErr,
						  "Invalid vertex shader input attribute '%s'.\n"
						  "\n"
						  "Valid input attributes:\n"
						  "  a_position, a_normal, a_tangent, a_bitangent, a_color0, a_color1, a_color2, a_color3, a_indices, a_weight,\n"
						  "  a_texcoord0, a_texcoord1, a_texcoord2, a_texcoord3, a_texcoord4, a_texcoord5, a_texcoord6, a_texcoord7,\n"
						  "  i_data0, i_data1, i_data2, i_data3, i_data4.\n"
						  "\n"
						, it->c_str() );
					break;
				}
			}
		}

		if (invalidShaderAttribute)
		{
		}
		else if (raw)
		{
			if ('f' == _options.shaderType)
			{
				bx::write(_shaderWriter, BGFX_CHUNK_MAGIC_FSH, &err);
			}
			else if ('v' == _options.shaderType)
			{
				bx::write(_shaderWriter, BGFX_CHUNK_MAGIC_VSH, &err);
			}
			else
			{
				bx::write(_shaderWriter, BGFX_CHUNK_MAGIC_CSH, &err);
			}

			bx::write(_shaderWriter, inputHash, &err);
			bx::write(_shaderWriter, outputHash, &err);
		}

		if (raw)
		{
			if (profile->lang == ShadingLang::GLSL)
			{
				bx::write(_shaderWriter, uint16_t(0), &err);

				const uint32_t shaderSize = (uint32_t)bx::strLen(input);
				bx::write(_shaderWriter, shaderSize, &err);
				bx::write(_shaderWriter, input, shaderSize, &err);
				bx::write(_shaderWriter, uint8_t(0), &err);

				compiled = true;
			}
			else if (profile->lang == ShadingLang::Metal)
			{
				compiled = compileMetalShader(_options, profile->id, input, _shaderWriter, _messageWriter);
			}
			else if (profile->lang == ShadingLang::SpirV)
			{
				compiled = compileSPIRVShader(_options, profile->id, input, _shaderWriter, _messageWriter);
			}
			else if (profile->lang == ShadingLang::PSSL)
			{
				compiled = compilePSSLShader(_options, 0, input, _shaderWriter, _messageWriter);
			}
			else
			{
				compiled = compileHLSLShader(_options, profile->id, input, _shaderWriter, _messageWriter);
			}
		}
		else if ('c' == _options.shaderType) // Compute
		{
			bx::StringView entry = bx::strFind(input, "void main()");
			if (entry.isEmpty() )
			{
				bx::write(_messageWriter, &messageErr, "Shader entry point 'void main()' is not found.\n");
			}
			else
			{
				if (profile->lang == ShadingLang::GLSL
				||  profile->lang == ShadingLang::ESSL)
				{
				}
				else
				{
					if (profile->lang == ShadingLang::PSSL)
					{
						preprocessor.writef(getPsslPreamble() );
					}

					preprocessor.writef(
						"#define lowp\n"
						"#define mediump\n"
						"#define highp\n"
						"#define ivec2 int2\n"
						"#define ivec3 int3\n"
						"#define ivec4 int4\n"
						"#define uvec2 uint2\n"
						"#define uvec3 uint3\n"
						"#define uvec4 uint4\n"
						"#define vec2 float2\n"
						"#define vec3 float3\n"
						"#define vec4 float4\n"
						"#define mat2 float2x2\n"
						"#define mat3 float3x3\n"
						"#define mat4 float4x4\n"
						);

					*const_cast<char*>(entry.getPtr() + 4) = '_';

					preprocessor.writef("#define void_main()");
					preprocessor.writef(" \\\n\tvoid main(");

					uint32_t arg = 0;

					const bool hasLocalInvocationID    = !bx::strFind(input, "gl_LocalInvocationID").isEmpty();
					const bool hasLocalInvocationIndex = !bx::strFind(input, "gl_LocalInvocationIndex").isEmpty();
					const bool hasGlobalInvocationID   = !bx::strFind(input, "gl_GlobalInvocationID").isEmpty();
					const bool hasWorkGroupID          = !bx::strFind(input, "gl_WorkGroupID").isEmpty();

					if (hasLocalInvocationID)
					{
						preprocessor.writef(
							" \\\n\t%sint3 gl_LocalInvocationID : SV_GroupThreadID"
							, arg++ > 0 ? ", " : "  "
							);
					}

					if (hasLocalInvocationIndex)
					{
						preprocessor.writef(
							" \\\n\t%sint gl_LocalInvocationIndex : SV_GroupIndex"
							, arg++ > 0 ? ", " : "  "
							);
					}

					if (hasGlobalInvocationID)
					{
						preprocessor.writef(
							" \\\n\t%sint3 gl_GlobalInvocationID : SV_DispatchThreadID"
							, arg++ > 0 ? ", " : "  "
							);
					}

					if (hasWorkGroupID)
					{
						preprocessor.writef(
							" \\\n\t%sint3 gl_WorkGroupID : SV_GroupID"
							, arg++ > 0 ? ", " : "  "
							);
					}

					preprocessor.writef(
						" \\\n\t)\n"
						);
				}

				if (preprocessor.run(input) )
				{
					if (_options.preprocessOnly)
					{
						bx::write(
							_shaderWriter
							, preprocessor.m_preprocessed.c_str()
							, (int32_t)preprocessor.m_preprocessed.size()
							, &err
							);

						return true;
					}

					{
						std::string code;

						bx::write(_shaderWriter, BGFX_CHUNK_MAGIC_CSH, &err);
						bx::write(_shaderWriter, uint32_t(0), &err);
						bx::write(_shaderWriter, outputHash, &err);

						if (profile->lang == ShadingLang::GLSL
						||  profile->lang == ShadingLang::ESSL)
						{
							if (profile->lang == ShadingLang::ESSL)
							{
								bx::stringPrintf(code, "#version 310 es\n");
							}
							else
							{
								bx::stringPrintf(
									  code
									, "#version %d\n"
									, (profile->lang != ShadingLang::GLSL) ? 430 : profile->id
									);
							}

							code += preprocessor.m_preprocessed;

							bx::write(_shaderWriter, uint16_t(0), &err);

							uint32_t shaderSize = (uint32_t)code.size();
							bx::write(_shaderWriter, shaderSize, &err);
							bx::write(_shaderWriter, code.c_str(), shaderSize, &err);
							bx::write(_shaderWriter, uint8_t(0), &err);

							compiled = true;
						}
						else
						{
							code += _comment;
							code += preprocessor.m_preprocessed;

							if (profile->lang == ShadingLang::Metal)
							{
								compiled = compileMetalShader(_options, profile->id, code, _shaderWriter, _messageWriter);
							}
							else if (profile->lang == ShadingLang::SpirV)
							{
								compiled = compileSPIRVShader(_options, profile->id, code, _shaderWriter, _messageWriter);
							}
							else if (profile->lang == ShadingLang::PSSL)
							{
								compiled = compilePSSLShader(_options, 0, code, _shaderWriter, _messageWriter);
							}
							else
							{
								compiled = compileHLSLShader(_options, profile->id, code, _shaderWriter, _messageWriter);
							}
						}
					}

					if (compiled)
					{
						if (_options.depends)
						{
							std::string ofp = _options.outputFilePath;
							ofp += ".d";
							bx::FileWriter writer;
							if (bx::open(&writer, ofp.c_str() ) )
							{
								writef(&writer, "%s : %s\n", _options.outputFilePath.c_str(), preprocessor.m_depends.c_str() );
								bx::close(&writer);
							}
						}
					}
				}
			}
		}
		else // Vertex/Fragment
		{
			bx::StringView shader(input);
			bx::StringView entry = bx::strFind(shader, "void main()");
			if (entry.isEmpty() )
			{
				bx::write(_messageWriter, &messageErr, "Shader entry point 'void main()' is not found.\n");
			}
			else
			{
				if (profile->lang == ShadingLang::GLSL
				||  profile->lang == ShadingLang::ESSL)
				{
					if (profile->lang != ShadingLang::ESSL)
					{
						// bgfx shadow2D/Proj behave like EXT_shadow_samplers
						// not as GLSL language 1.2 specs shadow2D/Proj.
						preprocessor.writef(
							"#define shadow2D(_sampler, _coord) bgfxShadow2D(_sampler, _coord).x\n"
							"#define shadow2DProj(_sampler, _coord) bgfxShadow2DProj(_sampler, _coord).x\n"
							);
					}

					// gl_FragColor and gl_FragData are deprecated for essl > 300
					if (profile->lang == ShadingLang::ESSL
					&&  profile->id >= 300)
					{
						const bool hasFragColor   = !bx::strFind(input, "gl_FragColor").isEmpty();
						bool hasFragData[8] = {};
						uint32_t numFragData = 0;
						for (uint32_t ii = 0; ii < BX_COUNTOF(hasFragData); ++ii)
						{
							char temp[32];
							bx::snprintf(temp, BX_COUNTOF(temp), "gl_FragData[%d]", ii);
							hasFragData[ii] = !bx::strFind(input, temp).isEmpty();
							numFragData += hasFragData[ii];
						}
						if (hasFragColor)
						{
							preprocessor.writef("#define gl_FragColor bgfx_FragColor\n");
							preprocessor.writef("out mediump vec4 bgfx_FragColor;\n");
						}
						else if (numFragData)
						{
							preprocessor.writef("#define gl_FragData bgfx_FragData\n");
							preprocessor.writef("out mediump vec4 bgfx_FragData[gl_MaxDrawBuffers];\n");
						}
					}

					for (InOut::const_iterator it = shaderInputs.begin(), itEnd = shaderInputs.end(); it != itEnd; ++it)
					{
						VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
						if (varyingIt != varyingMap.end() )
						{
							const Varying& var = varyingIt->second;
							const char* name = var.m_name.c_str();

							if (0 == bx::strCmp(name, "a_", 2)
							||  0 == bx::strCmp(name, "i_", 2) )
							{
								preprocessor.writef(
									  "attribute %s %s %s %s;\n"
									, var.m_precision.c_str()
									, var.m_interpolation.c_str()
									, var.m_type.c_str()
									, name
									);
							}
							else
							{
								preprocessor.writef(
									  "%s varying %s %s %s;\n"
									, var.m_interpolation.c_str()
									, var.m_precision.c_str()
									, var.m_type.c_str()
									, name
									);
							}
						}
					}

					for (InOut::const_iterator it = shaderOutputs.begin(), itEnd = shaderOutputs.end(); it != itEnd; ++it)
					{
						VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
						if (varyingIt != varyingMap.end() )
						{
							const Varying& var = varyingIt->second;
							preprocessor.writef("%s varying %s %s;\n"
								, var.m_interpolation.c_str()
								, var.m_type.c_str()
								, var.m_name.c_str()
								);
						}
					}
				}
				else
				{
					if (profile->lang == ShadingLang::PSSL)
					{
						preprocessor.writef(getPsslPreamble() );
					}

					preprocessor.writef(
						"#define lowp\n"
						"#define mediump\n"
						"#define highp\n"
						"#define ivec2 int2\n"
						"#define ivec3 int3\n"
						"#define ivec4 int4\n"
						"#define uvec2 uint2\n"
						"#define uvec3 uint3\n"
						"#define uvec4 uint4\n"
						"#define vec2 float2\n"
						"#define vec3 float3\n"
						"#define vec4 float4\n"
						"#define mat2 float2x2\n"
						"#define mat3 float3x3\n"
						"#define mat4 float4x4\n"
						);

					if (profile->lang == ShadingLang::HLSL
					&&  profile->id < 400)
					{
						preprocessor.writef(
							"#define centroid\n"
							"#define flat\n"
							"#define noperspective\n"
							"#define smooth\n"
							);
					}

					*const_cast<char*>(entry.getPtr() + 4) = '_';

					if ('f' == _options.shaderType)
					{
						bx::StringView insert = bx::strFind(bx::StringView(entry.getPtr(), shader.getTerm() ), "{");
						if (!insert.isEmpty() )
						{
							insert = strInsert(const_cast<char*>(insert.getPtr()+1), "\nvec4 bgfx_VoidFrag = vec4_splat(0.0);\n");
						}

						const bool hasFragColor   = !bx::strFind(input, "gl_FragColor").isEmpty();
						const bool hasFragCoord   = !bx::strFind(input, "gl_FragCoord").isEmpty() || profile->id >= 400;
						const bool hasFragDepth   = !bx::strFind(input, "gl_FragDepth").isEmpty();
						const bool hasFrontFacing = !bx::strFind(input, "gl_FrontFacing").isEmpty();
						const bool hasPrimitiveId = !bx::strFind(input, "gl_PrimitiveID").isEmpty() && BGFX_CAPS_PRIMITIVE_ID;

						if (!hasPrimitiveId)
						{
							preprocessor.writef("#define gl_PrimitiveID 0\n");
						}

						bool hasFragData[8] = {};
						uint32_t numFragData = 0;
						for (uint32_t ii = 0; ii < BX_COUNTOF(hasFragData); ++ii)
						{
							char temp[32];
							bx::snprintf(temp, BX_COUNTOF(temp), "gl_FragData[%d]", ii);
							hasFragData[ii] = !bx::strFind(input, temp).isEmpty();
							numFragData += hasFragData[ii];
						}

						if (0 == numFragData)
						{
							// GL errors when both gl_FragColor and gl_FragData is used.
							// This will trigger the same error with HLSL compiler too.
							preprocessor.writef("#define gl_FragColor bgfx_FragData0\n");

							// If it has gl_FragData or gl_FragColor, color target at
							// index 0 exists, otherwise shader is not modifying color
							// targets.
							hasFragData[0] |= hasFragColor || profile->id < 400;

							if (!insert.isEmpty()
							&&  profile->id < 400
							&&  !hasFragColor)
							{
								insert = strInsert(const_cast<char*>(insert.getPtr()+1), "\ngl_FragColor = bgfx_VoidFrag;\n");
							}
						}

						preprocessor.writef("#define void_main()");
						preprocessor.writef(" \\\n\tvoid main(");

						uint32_t arg = 0;

						if (hasFragCoord)
						{
							preprocessor.writef(" \\\n\tvec4 gl_FragCoord : SV_POSITION");
							++arg;
						}

						for (InOut::const_iterator it = shaderInputs.begin(), itEnd = shaderInputs.end(); it != itEnd; ++it)
						{
							VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
							if (varyingIt != varyingMap.end() )
							{
								const Varying& var = varyingIt->second;
								preprocessor.writef(" \\\n\t%s%s %s %s : %s"
									, arg++ > 0 ? ", " : "  "
									, interpolationDx11(var.m_interpolation.c_str() )
									, var.m_type.c_str()
									, var.m_name.c_str()
									, var.m_semantics.c_str()
									);
							}
						}

						const uint32_t maxRT = profile->id >= 400 ? BX_COUNTOF(hasFragData) : 4;

						for (uint32_t ii = 0; ii < BX_COUNTOF(hasFragData); ++ii)
						{
							if (ii < maxRT)
							{
								if (hasFragData[ii])
								{
									addFragData(preprocessor, input, ii, arg++ > 0);
								}
							}
							else
							{
								voidFragData(input, ii);
							}
						}

						if (hasFragDepth)
						{
							preprocessor.writef(
								" \\\n\t%sout float gl_FragDepth : SV_DEPTH"
								, arg++ > 0 ? ", " : "  "
								);
						}

						if (hasFrontFacing)
						{
							if (profile->id < 400)
							{
								preprocessor.writef(
									" \\\n\t%sfloat __vface : VFACE"
									, arg++ > 0 ? ", " : "  "
									);
							}
							else
							{
								preprocessor.writef(
									" \\\n\t%sbool gl_FrontFacing : SV_IsFrontFace"
									, arg++ > 0 ? ", " : "  "
									);
							}
						}

						if (hasPrimitiveId)
						{
							if (profile->id >= 400)
							{
								preprocessor.writef(
									" \\\n\t%suint gl_PrimitiveID : SV_PrimitiveID"
									, arg++ > 0 ? ", " : "  "
									);
							}
							else
							{
								bx::write(_messageWriter, &messageErr, "gl_PrimitiveID builtin is not supported by D3D9 HLSL.\n");
								return false;
							}
						}

						preprocessor.writef(
							" \\\n\t)\n"
							);

						if (hasFrontFacing)
						{
							if (profile->id < 400)
							{
								preprocessor.writef(
									"#define gl_FrontFacing (__vface >= 0.0)\n"
									);
							}
						}
					}
					else if ('v' == _options.shaderType)
					{
						const bool hasVertexId   = !bx::strFind(input, "gl_VertexID").isEmpty();
						const bool hasInstanceId = !bx::strFind(input, "gl_InstanceID").isEmpty();
						const bool hasViewportId = !bx::strFind(input, "gl_ViewportIndex").isEmpty();
						const bool hasLayerId    = !bx::strFind(input, "gl_Layer").isEmpty();

						bx::StringView brace = bx::strFind(bx::StringView(entry.getPtr(), shader.getTerm() ), "{");
						if (!brace.isEmpty() )
						{
							bx::StringView block = bx::strFindBlock(bx::StringView(brace.getPtr(), shader.getTerm() ), '{', '}');
							if (!block.isEmpty() )
							{
								strInsert(const_cast<char*>(block.getTerm()-1), "__RETURN__;\n");
							}
						}

						preprocessor.writef(
							"struct Output\n"
							"{\n"
							"\tvec4 gl_Position : SV_POSITION;\n"
							"#define gl_Position _varying_.gl_Position\n"
							);

						for (InOut::const_iterator it = shaderOutputs.begin(), itEnd = shaderOutputs.end(); it != itEnd; ++it)
						{
							VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
							if (varyingIt != varyingMap.end() )
							{
								const Varying& var = varyingIt->second;
								preprocessor.writef(
									  "\t%s %s %s : %s;\n"
									, interpolationDx11(var.m_interpolation.c_str() )
									, var.m_type.c_str()
									, var.m_name.c_str()
									, var.m_semantics.c_str()
									);
								preprocessor.writef(
									  "#define %s _varying_.%s\n"
									, var.m_name.c_str()
									, var.m_name.c_str()
									);
							}
						}

						if (hasViewportId)
						{
							if (profile->id >= 400)
							{
								preprocessor.writef(
									"\tuint gl_ViewportIndex : SV_ViewportArrayIndex;\n"
									"#define gl_ViewportIndex _varying_.gl_ViewportIndex\n"
									);
							}
							else
							{
								bx::write(_messageWriter, &messageErr, "gl_ViewportIndex builtin is not supported by D3D9 HLSL.\n");
								return false;
							}
						}

						if (hasLayerId)
						{
							if (profile->id >= 400)
							{
								preprocessor.writef(
									"\tuint gl_Layer : SV_RenderTargetArrayIndex;\n"
									"#define gl_Layer _varying_.gl_Layer\n"
									);
							}
							else
							{
								bx::write(_messageWriter, &messageErr, "gl_Layer builtin is not supported by D3D9 HLSL.\n");
								return false;
							}
						}

						preprocessor.writef(
							"};\n"
							);

						preprocessor.writef("#define void_main() \\\n");
						preprocessor.writef("Output main(");
						uint32_t arg = 0;
						for (InOut::const_iterator it = shaderInputs.begin(), itEnd = shaderInputs.end(); it != itEnd; ++it)
						{
							VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
							if (varyingIt != varyingMap.end() )
							{
								const Varying& var = varyingIt->second;
								preprocessor.writef(
									" \\\n\t%s%s %s : %s"
									, arg++ > 0 ? ", " : ""
									, var.m_type.c_str()
									, var.m_name.c_str()
									, var.m_semantics.c_str()
									);
							}
						}

						if (hasVertexId)
						{
							if (profile->id >= 400)
							{
								preprocessor.writef(
									" \\\n\t%suint gl_VertexID : SV_VertexID"
									, arg++ > 0 ? ", " : "  "
									);
							}
							else
							{
								bx::write(_messageWriter, &messageErr, "gl_VertexID builtin is not supported by D3D9 HLSL.\n");
								return false;
							}
						}

						if (hasInstanceId)
						{
							if (profile->id >= 400)
							{
								preprocessor.writef(
									" \\\n\t%suint gl_InstanceID : SV_InstanceID"
									, arg++ > 0 ? ", " : "  "
									);
							}
							else
							{
								bx::write(_messageWriter, &messageErr, "gl_InstanceID builtin is not supported by D3D9 HLSL.\n");
								return false;
							}
						}

						preprocessor.writef(
							") \\\n"
							"{ \\\n"
							"\tOutput _varying_;"
							);

						for (InOut::const_iterator it = shaderOutputs.begin(), itEnd = shaderOutputs.end(); it != itEnd; ++it)
						{
							VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
							if (varyingIt != varyingMap.end() )
							{
								const Varying& var = varyingIt->second;
								preprocessor.writef(" \\\n\t%s", var.m_name.c_str() );
								if (!var.m_init.empty() )
								{
									preprocessor.writef(" = %s", var.m_init.c_str() );
								}
								preprocessor.writef(";");
							}
						}

						preprocessor.writef(
							"\n#define __RETURN__ \\\n"
							"\t} \\\n"
							);

						preprocessor.writef(
							"\treturn _varying_"
							);
					}
				}

				if (preprocessor.run(input) )
				{
					if (_options.preprocessOnly)
					{
						bx::write(
							_shaderWriter
							, preprocessor.m_preprocessed.c_str()
							, (int32_t)preprocessor.m_preprocessed.size()
							, &err
							);

						return true;
					}

					{
						std::string code;

						if ('f' == _options.shaderType)
						{
							bx::write(_shaderWriter, BGFX_CHUNK_MAGIC_FSH, &err);
							bx::write(_shaderWriter, inputHash, &err);
							bx::write(_shaderWriter, uint32_t(0), &err);
						}
						else if ('v' == _options.shaderType)
						{
							bx::write(_shaderWriter, BGFX_CHUNK_MAGIC_VSH, &err);
							bx::write(_shaderWriter, uint32_t(0), &err);
							bx::write(_shaderWriter, outputHash, &err);
						}
						else
						{
							bx::write(_shaderWriter, BGFX_CHUNK_MAGIC_CSH, &err);
							bx::write(_shaderWriter, uint32_t(0), &err);
							bx::write(_shaderWriter, outputHash, &err);
						}

						if (profile->lang == ShadingLang::GLSL
						||  profile->lang == ShadingLang::ESSL)
						{
							const bx::StringView preprocessedInput(preprocessor.m_preprocessed.c_str() );
							uint32_t glsl_profile = profile->id;

							const bool usesBitsToEncoders = true
								&& _options.shaderType == 'f'
								&& !bx::findIdentifierMatch(preprocessedInput, s_bitsToEncoders).isEmpty()
								;

							if (!bx::strFind(preprocessedInput, "layout(std430").isEmpty()
							||  !bx::strFind(preprocessedInput, "image2D").isEmpty()
							||  usesBitsToEncoders)
							{
								if (profile->lang == ShadingLang::GLSL
								&&  glsl_profile < 430)
								{
									glsl_profile = 430;
								}
								else if (glsl_profile < 310)
								{
									glsl_profile = 310;
								}
							}

							if (glsl_profile < 400)
							{
								const bool usesTextureLod   = false
									|| !bx::findIdentifierMatch(input, s_ARB_shader_texture_lod).isEmpty()
									|| !bx::findIdentifierMatch(input, s_EXT_shader_texture_lod).isEmpty()
									;

								const bool usesGpuShader5 = true
									&& _options.shaderType != 'f'
									&& !bx::findIdentifierMatch(input, s_ARB_gpu_shader5).isEmpty()
									;

								const bool usesInstanceID         = !bx::findIdentifierMatch(input, "gl_InstanceID").isEmpty();
								const bool usesGpuShader4         = !bx::findIdentifierMatch(input, s_EXT_gpu_shader4).isEmpty();
								const bool usesTexelFetch         = !bx::findIdentifierMatch(input, s_texelFetch).isEmpty();
								const bool usesTextureMS          = !bx::findIdentifierMatch(input, s_ARB_texture_multisample).isEmpty();
								const bool usesTextureArray       = !bx::findIdentifierMatch(input, s_textureArray).isEmpty();
								const bool usesPacking            = !bx::findIdentifierMatch(input, s_ARB_shading_language_packing).isEmpty();
								const bool usesViewportLayerArray = !bx::findIdentifierMatch(input, s_ARB_shader_viewport_layer_array).isEmpty();
								const bool usesUnsignedVecs       = !bx::findIdentifierMatch(preprocessedInput, s_unsignedVecs).isEmpty();

								if (profile->lang != ShadingLang::ESSL)
								{
									const bool need130 = (120 == glsl_profile && (false
										|| !bx::findIdentifierMatch(input, s_130).isEmpty()
										|| usesInterpolationQualifiers
										|| usesTexelFetch
										|| usesUnsignedVecs
										) );

									bx::stringPrintf(code, "#version %d\n", need130 ? 130 : glsl_profile);

									if (need130)
									{
										bx::stringPrintf(code, "#define varying %s\n"
											, 'f' == _options.shaderType ? "in" : "out"
											);
									}

									if (usesInstanceID)
									{
										bx::stringPrintf(code
											, "#extension GL_ARB_draw_instanced : enable\n"
											);
									}

									if (usesViewportLayerArray)
									{
										bx::stringPrintf(code
											, "#extension GL_ARB_shader_viewport_layer_array : enable\n"
											);
									}

									if (usesGpuShader4)
									{
										bx::stringPrintf(code
											, "#extension GL_EXT_gpu_shader4 : enable\n"
											);
									}

									if (usesGpuShader5)
									{
										bx::stringPrintf(code
											, "#extension GL_ARB_gpu_shader5 : enable\n"
											);
									}

									if (usesPacking)
									{
										bx::stringPrintf(code
											, "#extension GL_ARB_shading_language_packing : enable\n"
											);
									}

									bool ARB_shader_texture_lod = false;
									bool EXT_shader_texture_lod = false;

									if (usesTextureLod)
									{
										if ('f' == _options.shaderType)
										{
											ARB_shader_texture_lod = true;
											bx::stringPrintf(code
												, "#extension GL_ARB_shader_texture_lod : enable\n"
												);
										}
										else
										{
											EXT_shader_texture_lod = true;
											bx::stringPrintf(code
												, "#extension GL_EXT_shader_texture_lod : enable\n"
												);
										}
									}

									if (usesTextureMS)
									{
										bx::stringPrintf(code
											, "#extension GL_ARB_texture_multisample : enable\n"
											);
									}

									if (usesTextureArray)
									{
										bx::stringPrintf(code
											, "#extension GL_EXT_texture_array : enable\n"
											);
									}

									if (130 > glsl_profile)
									{
										bx::stringPrintf(code,
											"#define ivec2 vec2\n"
											"#define ivec3 vec3\n"
											"#define ivec4 vec4\n"
											);
									}

									if (ARB_shader_texture_lod)
									{
										bx::stringPrintf(code,
											"#define texture2DProjLod  texture2DProjLodARB\n"
											"#define texture2DGrad     texture2DGradARB\n"
											"#define texture2DProjGrad texture2DProjGradARB\n"
											"#define textureCubeGrad   textureCubeGradARB\n"
											);
									}
									else if (EXT_shader_texture_lod)
									{
										bx::stringPrintf(code,
											"#define texture2DProjLod  texture2DProjLodEXT\n"
											"#define texture2DGrad     texture2DGradEXT\n"
											"#define texture2DProjGrad texture2DProjGradEXT\n"
											"#define textureCubeGrad   textureCubeGradEXT\n"
											);
									}

									if (need130 || (glsl_profile >= 130) )
									{
										bx::stringPrintf(code
											, "#define bgfxShadow2D(_sampler, _coord)     vec4_splat(texture(_sampler, _coord) )\n"
											  "#define bgfxShadow2DProj(_sampler, _coord) vec4_splat(textureProj(_sampler, _coord) )\n"
											);
									}
									else
									{
										bx::stringPrintf(code
											, "#define bgfxShadow2D     shadow2D\n"
											  "#define bgfxShadow2DProj shader2DProj\n"
											);
									}
								}
								else
								{
									if (glsl_profile < 300
									&&  usesUnsignedVecs)
									{
										glsl_profile = 300;
									}

									if (glsl_profile > 100)
									{
										bx::stringPrintf(code, "#version %d es\n", glsl_profile);
										bx::stringPrintf(code, "#define attribute in\n");
										bx::stringPrintf(code, "#define varying %s\n"
											, 'f' == _options.shaderType ? "in" : "out"
											);
										bx::stringPrintf(code, "precision highp float;\n");
										bx::stringPrintf(code, "precision highp int;\n");
									}

									if (glsl_profile >= 300 && usesTextureArray)
									{
										bx::stringPrintf(code, "precision highp sampler2DArray;\n");
									}

									// Pretend that all extensions are available.
									// This will be stripped later.
									if (usesTextureLod)
									{
										bx::stringPrintf(code
											, "#extension GL_EXT_shader_texture_lod : enable\n"
											  "#define texture2DLod      texture2DLodEXT\n"
											  "#define texture2DGrad     texture2DGradEXT\n"
											  "#define texture2DProjLod  texture2DProjLodEXT\n"
											  "#define texture2DProjGrad texture2DProjGradEXT\n"
											  "#define textureCubeLod    textureCubeLodEXT\n"
											  "#define textureCubeGrad   textureCubeGradEXT\n"
											);
									}

									if (!bx::findIdentifierMatch(input, s_OES_standard_derivatives).isEmpty() )
									{
										bx::stringPrintf(code, "#extension GL_OES_standard_derivatives : enable\n");
									}

									if (!bx::findIdentifierMatch(input, s_OES_texture_3D).isEmpty() )
									{
										bx::stringPrintf(code, "#extension GL_OES_texture_3D : enable\n");
									}

									if (glsl_profile < 300
									&&  !bx::findIdentifierMatch(input, s_EXT_shadow_samplers).isEmpty() )
									{
										bx::stringPrintf(code
											, "#extension GL_EXT_shadow_samplers : enable\n"
											  "#define shadow2D shadow2DEXT\n"
											  "#define shadow2DProj shadow2DProjEXT\n"
											);
									}
									else
									{
										bx::stringPrintf(code
											, "#define shadow2D(_sampler, _coord) texture(_sampler, _coord)\n"
											  "#define shadow2DProj(_sampler, _coord) textureProj(_sampler, _coord)\n"
											);
									}

									if (usesGpuShader5)
									{
										bx::stringPrintf(code
											, "#extension GL_ARB_gpu_shader5 : enable\n"
											);
									}

									if (usesPacking)
									{
										bx::stringPrintf(code
											, "#extension GL_ARB_shading_language_packing : enable\n"
											);
									}

									if (glsl_profile < 300
									&&  !bx::findIdentifierMatch(input, "gl_FragDepth").isEmpty() )
									{
										bx::stringPrintf(code
											, "#extension GL_EXT_frag_depth : enable\n"
											  "#define gl_FragDepth gl_FragDepthEXT\n"
											);
									}

									if (usesTextureArray)
									{
										bx::stringPrintf(code
											, "#extension GL_EXT_texture_array : enable\n"
											);
									}

									if (glsl_profile == 100)
									{
										code +=
											"mat2 transpose(mat2 _mtx)\n"
											"{\n"
											"	vec2 v0 = _mtx[0];\n"
											"	vec2 v1 = _mtx[1];\n"
											"\n"
											"	return mat2(\n"
											"		  vec2(v0.x, v1.x)\n"
											"		, vec2(v0.y, v1.y)\n"
											"		);\n"
											"}\n"
											"\n"
											"mat3 transpose(mat3 _mtx)\n"
											"{\n"
											"	vec3 v0 = _mtx[0];\n"
											"	vec3 v1 = _mtx[1];\n"
											"	vec3 v2 = _mtx[2];\n"
											"\n"
											"	return mat3(\n"
											"		  vec3(v0.x, v1.x, v2.x)\n"
											"		, vec3(v0.y, v1.y, v2.y)\n"
											"		, vec3(v0.z, v1.z, v2.z)\n"
											"		);\n"
											"}\n"
											"\n"
											"mat4 transpose(mat4 _mtx)\n"
											"{\n"
											"	vec4 v0 = _mtx[0];\n"
											"	vec4 v1 = _mtx[1];\n"
											"	vec4 v2 = _mtx[2];\n"
											"	vec4 v3 = _mtx[3];\n"
											"\n"
											"	return mat4(\n"
											"		  vec4(v0.x, v1.x, v2.x, v3.x)\n"
											"		, vec4(v0.y, v1.y, v2.y, v3.y)\n"
											"		, vec4(v0.z, v1.z, v2.z, v3.z)\n"
											"		, vec4(v0.w, v1.w, v2.w, v3.w)\n"
											"		);\n"
											"}\n"
											;
									}
								}
							}
							else
							{
								bx::stringPrintf(code, "#version %d\n", glsl_profile);

								if (120 < glsl_profile)
								{
									if (!bx::findIdentifierMatch(input, "gl_FragColor").isEmpty() )
									{
										bx::stringPrintf(code
											, "out vec4 bgfx_FragColor;\n"
											  "#define gl_FragColor bgfx_FragColor\n"
											);
									}
								}

								bx::stringPrintf(code
									, "#define texture2D          texture\n"
									  "#define texture2DLod       textureLod\n"
									  "#define texture2DGrad      textureGrad\n"
									  "#define texture2DProjLod   textureProjLod\n"
									  "#define texture2DProjGrad  textureProjGrad\n"
									  "#define textureCubeLod     textureLod\n"
									  "#define textureCubeGrad    textureGrad\n"
									  "#define texture3D          texture\n"
									  "#define texture2DLodOffset textureLodOffset\n"
									);

								bx::stringPrintf(code, "#define attribute in\n");
								bx::stringPrintf(code, "#define varying %s\n"
									, 'f' == _options.shaderType ? "in" : "out"
									);

								bx::stringPrintf(code
									, "#define bgfxShadow2D(_sampler, _coord)     vec4_splat(texture(_sampler, _coord) )\n"
									  "#define bgfxShadow2DProj(_sampler, _coord) vec4_splat(textureProj(_sampler, _coord) )\n"
									);
							}

							if ( (profile->lang == ShadingLang::GLSL && glsl_profile > 400)
							||   (profile->lang == ShadingLang::ESSL && glsl_profile > 300) )
							{
								code += preprocessor.m_preprocessed;

								bx::write(_shaderWriter, uint16_t(0), &err);

								uint32_t shaderSize = (uint32_t)code.size();
								bx::write(_shaderWriter, shaderSize, &err);
								bx::write(_shaderWriter, code.c_str(), shaderSize, &err);
								bx::write(_shaderWriter, uint8_t(0), &err);

								compiled = true;
							}
							else
							{
								code += _comment;
								code += preprocessor.m_preprocessed;

								if (profile->lang == ShadingLang::ESSL)
								{
									glsl_profile |= 0x80000000;
								}

								compiled = compileGLSLShader(_options, glsl_profile, code, _shaderWriter, _messageWriter);
							}
						}
						else
						{
							code += _comment;
							code += preprocessor.m_preprocessed;

							if (profile->lang == ShadingLang::Metal)
							{
								compiled = compileMetalShader(_options, profile->id, code, _shaderWriter, _messageWriter);
							}
							else if (profile->lang == ShadingLang::SpirV)
							{
								compiled = compileSPIRVShader(_options, profile->id, code, _shaderWriter, _messageWriter);
							}
							else if (profile->lang == ShadingLang::PSSL)
							{
								compiled = compilePSSLShader(_options, 0, code, _shaderWriter, _messageWriter);
							}
							else
							{
								compiled = compileHLSLShader(_options, profile->id, code, _shaderWriter, _messageWriter);
							}
						}
					}

					if (compiled)
					{
						if (_options.depends)
						{
							std::string ofp = _options.outputFilePath + ".d";
							bx::FileWriter writer;
							if (bx::open(&writer, ofp.c_str() ) )
							{
								writef(&writer, "%s : %s\n", _options.outputFilePath.c_str(), preprocessor.m_depends.c_str() );
								bx::close(&writer);
							}
						}
					}
				}
			}
		}

		delete [] data;

		return compiled;
	}

	int compileShader(int _argc, const char* _argv[])
	{
		bx::CommandLine cmdLine(_argc, _argv);

		if (cmdLine.hasArg('v', "version") )
		{
			bx::printf(
				  "shaderc, bgfx shader compiler tool, version %d.%d.%d.\n"
				, BGFX_SHADERC_VERSION_MAJOR
				, BGFX_SHADERC_VERSION_MINOR
				, BGFX_API_VERSION
				);
			return bx::kExitSuccess;
		}

		if (cmdLine.hasArg('h', "help") )
		{
			help();
			return bx::kExitFailure;
		}

		g_verbose = cmdLine.hasArg("verbose");

		const char* filePath = cmdLine.findOption('f');
		if (NULL == filePath)
		{
			help("Shader file name must be specified.");
			return bx::kExitFailure;
		}

		bool consoleOut = cmdLine.hasArg("stdout");
		const char* outFilePath = cmdLine.findOption('o');
		if (NULL == outFilePath
		&&  !consoleOut)
		{
			help("Output file name must be specified or use \"--stdout\" to output to stdout.");
			return bx::kExitFailure;
		}

		const char* type = cmdLine.findOption('\0', "type");
		if (NULL == type)
		{
			help("Must specify shader type.");
			return bx::kExitFailure;
		}

		Options options;
		options.inputFilePath = filePath;
		options.outputFilePath = consoleOut ? "" : outFilePath;
		options.shaderType = bx::toLower(type[0]);

		options.disasm = cmdLine.hasArg('\0', "disasm");

		const char* platform = cmdLine.findOption('\0', "platform");
		if (NULL == platform)
		{
			platform = "";
		}

		options.platform = platform;

		options.raw = cmdLine.hasArg('\0', "raw");

		const char* profile = cmdLine.findOption('p', "profile");

		if ( NULL != profile)
		{
			options.profile = profile;
		}

		{
			options.debugInformation       = cmdLine.hasArg('\0', "debug");
			options.avoidFlowControl       = cmdLine.hasArg('\0', "avoid-flow-control");
			options.noPreshader            = cmdLine.hasArg('\0', "no-preshader");
			options.partialPrecision       = cmdLine.hasArg('\0', "partial-precision");
			options.preferFlowControl      = cmdLine.hasArg('\0', "prefer-flow-control");
			options.backwardsCompatibility = cmdLine.hasArg('\0', "backwards-compatibility");
			options.warningsAreErrors      = cmdLine.hasArg('\0', "Werror");
			options.keepIntermediate       = cmdLine.hasArg('\0', "keep-intermediate");

			uint32_t optimization = 3;
			if (cmdLine.hasArg(optimization, 'O') )
			{
				options.optimize = true;
				options.optimizationLevel = optimization;
			}
		}

		bx::StringView bin2c;
		if (cmdLine.hasArg("bin2c") )
		{
			const char* bin2cArg = cmdLine.findOption("bin2c");
			if (NULL != bin2cArg)
			{
				bin2c.set(bin2cArg);
			}
			else
			{
				bin2c = baseName(outFilePath);
				if (!bin2c.isEmpty() )
				{
					char* temp = (char*)alloca(bin2c.getLength()+1);
					for (uint32_t ii = 0, num = bin2c.getLength(); ii < num; ++ii)
					{
						char ch = bin2c.getPtr()[ii];
						if (bx::isAlphaNum(ch) )
						{
							temp[ii] = ch;
						}
						else
						{
							temp[ii] = '_';
						}
					}

					temp[bin2c.getLength()] = '\0';

					bin2c = temp;
				}
			}
		}

		options.depends = cmdLine.hasArg("depends");
		options.preprocessOnly = cmdLine.hasArg("preprocess");
		const char* includeDir = cmdLine.findOption('i');

		BX_TRACE("depends: %d", options.depends);
		BX_TRACE("preprocessOnly: %d", options.preprocessOnly);
		BX_TRACE("includeDir: %s", includeDir);

		for (int ii = 1; NULL != includeDir; ++ii)
		{
			options.includeDirs.push_back(includeDir);
			includeDir = cmdLine.findOption(ii, 'i');
		}

		std::string dir;
		{
			bx::FilePath fp(filePath);
			bx::StringView path(fp.getPath() );

			dir.assign(path.getPtr(), path.getTerm() );
			options.includeDirs.push_back(dir);
		}

		const char* defines = cmdLine.findOption("define");
		while (NULL != defines
		&&    '\0'  != *defines)
		{
			defines = bx::strLTrimSpace(defines).getPtr();
			bx::StringView eol = bx::strFind(defines, ';');
			std::string define(defines, eol.getPtr() );
			options.defines.push_back(define.c_str() );
			defines = ';' == *eol.getPtr() ? eol.getPtr()+1 : eol.getPtr();
		}

		std::string commandLineComment = "// shaderc command line:\n//";
		for (int32_t ii = 0, num = cmdLine.getNum(); ii < num; ++ii)
		{
			commandLineComment += " ";
			commandLineComment += cmdLine.get(ii);
		}
		commandLineComment += "\n\n";

		bool compiled = false;

		bx::FileReader reader;
		if (!bx::open(&reader, filePath) )
		{
			bx::printf("Unable to open file '%s'.\n", filePath);
		}
		else
		{
			const char* varying = NULL;
			File attribdef;

			if ('c' != options.shaderType)
			{
				std::string defaultVarying = dir + "varying.def.sc";
				const char* varyingdef = cmdLine.findOption("varyingdef", defaultVarying.c_str() );
				attribdef.load(varyingdef);
				varying = attribdef.getData();

				if (NULL     != varying
				&&  *varying != '\0')
				{
					options.dependencies.push_back(varyingdef);
				}
				else
				{
					bx::printf("ERROR: Failed to parse varying def file: \"%s\" No input/output semantics will be generated in the code!\n", varyingdef);
				}
			}

			int32_t size = (int32_t)bx::getSize(&reader);
			const int32_t total = size + 16384;
			char* data = new char[total];
			size = bx::read(&reader, data, size, bx::ErrorAssert{});

			// Trim UTF-8 BOM
			if (data[0] == '\xef'
			&&  data[1] == '\xbb'
			&&  data[2] == '\xbf')
			{
				bx::memMove(data, &data[3], size-3);
				size -= 3;
			}

			const char ch = data[0];
			if (false // https://en.wikipedia.org/wiki/Byte_order_mark#Byte_order_marks_by_encoding
			||  '\x00' == ch
			||  '\x0e' == ch
			||  '\x2b' == ch
			||  '\x84' == ch
			||  '\xdd' == ch
			||  '\xf7' == ch
			||  '\xfb' == ch
			||  '\xfe' == ch
			||  '\xff' == ch
			   )
			{
				bx::printf("Shader input file has unsupported BOM.\n");
				return bx::kExitFailure;
			}

			// Compiler generates "error X3000: syntax error: unexpected end of file"
			// if input doesn't have empty line at EOF.
			data[size] = '\n';
			bx::memSet(&data[size+1], 0, total-size-1);
			bx::close(&reader);

			{
				bx::FileWriter* writer = NULL;

				if (!consoleOut)
				{
					if (!bin2c.isEmpty() )
					{
						writer = new Bin2cWriter(bin2c);
					}
					else
					{
						writer = new bx::FileWriter;
					}

					if (!bx::open(writer, outFilePath) )
					{
						bx::printf("Unable to open output file '%s'.\n", outFilePath);
						return bx::kExitFailure;
					}
				}

				compiled = compileShader(
						  varying
						, commandLineComment.c_str()
						, data
						, size
						, options
						, consoleOut ? bx::getStdOut() : writer
						, bx::getStdOut()
						);

				if (!consoleOut)
				{
					bx::close(writer);
					delete writer;
				}
			}
		}

		if (compiled)
		{
			return bx::kExitSuccess;
		}

		bx::remove(outFilePath);

		bx::printf("Failed to build shader.\n");
		return bx::kExitFailure;
	}

} // namespace bgfx

int main(int _argc, const char* _argv[])
{
	return bgfx::compileShader(_argc, _argv);
}