// smol-v - public domain - https://github.com/aras-p/smol-v // authored 2016-2020 by Aras Pranckevicius // no warranty implied; use at your own risk // See end of file for license information. // // // ### OVERVIEW: // // SMOL-V encodes Vulkan/Khronos SPIR-V format programs into a form that is smaller, and is more // compressible. Normally no changes to the programs are done; they decode // into exactly same program as what was encoded. Optionally, debug information // can be removed too. // // SPIR-V is a very verbose format, several times larger than same programs expressed in other // shader formats (e.g. DX11 bytecode, GLSL, DX9 bytecode etc.). The SSA-form with ever increasing // IDs is not very appreciated by regular data compressors either. SMOL-V does several things // to improve this: // - Many words, especially ones that most often have small values, are encoded using // "varint" scheme (1-5 bytes per word, with just one byte for values in 0..127 range). // See https://developers.google.com/protocol-buffers/docs/encoding // - Some IDs used in the program are delta-encoded, relative to previously seen IDs (e.g. Result // IDs). Often instructions reference things that were computed just before, so this results in // small deltas. These values are also encoded using "varint" scheme. // - Reordering instruction opcodes so that the most common ones are the smallest values, for smaller // varint encoding. // - Encoding several instructions in a more compact form, e.g. the "typical <=4 component swizzle" // shape of a VectorShuffle instruction, or sequences of MemberDecorate instructions. // // A somewhat similar utility is spirv-remap from glslang, see // https://github.com/KhronosGroup/glslang/blob/master/README-spirv-remap.txt // // // ### USAGE: // // Add source/smolv.h and source/smolv.cpp to your C++ project build. // Currently it might require C++11 or somesuch; I only tested with Visual Studio 2017/2019, Mac Xcode 11 and Gcc 5.4. // // smolv::Encode and smolv::Decode is the basic functionality. // // Other functions are for development/statistics purposes, to figure out frequencies and // distributions of the instructions. // // There's a test + compression benchmarking suite in testing/testmain.cpp; using that needs adding // other files under testing/external to the build too (3rd party code: glslang remapper, Zstd, LZ4). // // // ### LIMITATIONS / TODO: // // - SPIR-V where the words got stored in big-endian layout is not supported yet. // - The whole thing might not work on Big-Endian CPUs. It might, but I'm not 100% sure. // - Not much prevention is done against malformed/corrupted inputs, TODO. // - Out of memory cases are not handled. The code will either throw exception // or crash, depending on your compilation flags. #pragma once #include <stdint.h> #include <vector> #include <cstddef> namespace smolv { typedef std::vector<uint8_t> ByteArray; enum EncodeFlags { kEncodeFlagNone = 0, kEncodeFlagStripDebugInfo = (1<<0), // Strip all optional SPIR-V instructions (debug names etc.) }; enum DecodeFlags { kDecodeFlagNone = 0, kDecodeFlagUse20160831AsZeroVersion = (1 << 0), // For "version zero" of SMOL-V encoding, use 2016 08 31 code path (this is what happens to be used by Unity 2017-2020) }; // Preserve *some* OpName debug names. // Return true to preserve, false to strip. // This is really only used to implement a workaround for problems with some Vulkan drivers. typedef bool(*StripOpNameFilterFunc)(const char* name); // ------------------------------------------------------------------- // Encoding / Decoding // Encode SPIR-V into SMOL-V. // // Resulting data is appended to outSmolv array (the array is not cleared). // // flags is bitset of EncodeFlags values. // // Returns false on malformed SPIR-V input; if that happens the output array might get // partial/broken SMOL-V program. bool Encode(const void* spirvData, size_t spirvSize, ByteArray& outSmolv, uint32_t flags = kEncodeFlagNone, StripOpNameFilterFunc stripFilter = 0); // Decode SMOL-V into SPIR-V. // // Resulting data is written into the passed buffer. Get required buffer space with // GetDecodeBufferSize; this is the size of decoded SPIR-V program. // // flags is bitset of DecodeFlags values. // Decoding does no memory allocations. // // Returns false on malformed input; if that happens the output buffer might be only partially // written to. bool Decode(const void* smolvData, size_t smolvSize, void* spirvOutputBuffer, size_t spirvOutputBufferSize, uint32_t flags = kDecodeFlagNone); // Given a SMOL-V program, get size of the decoded SPIR-V program. // This is the buffer size that Decode expects. // // Returns zero on malformed input (just checks the header, not the full input). size_t GetDecodedBufferSize(const void* smolvData, size_t smolvSize); // ------------------------------------------------------------------- // Computing instruction statistics on SPIR-V/SMOL-V programs struct Stats; Stats* StatsCreate(); void StatsDelete(Stats* s); bool StatsCalculate(Stats* stats, const void* spirvData, size_t spirvSize); bool StatsCalculateSmol(Stats* stats, const void* smolvData, size_t smolvSize); void StatsPrint(const Stats* stats); } // namespace smolv // ------------------------------------------------------------------------------ // This software is available under 2 licenses -- choose whichever you prefer. // ------------------------------------------------------------------------------ // ALTERNATIVE A - MIT License // Copyright (c) 2016-2020 Aras Pranckevicius // Permission is hereby granted, free of charge, to any person obtaining a copy of // this software and associated documentation files (the "Software"), to deal in // the Software without restriction, including without limitation the rights to // use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies // of the Software, and to permit persons to whom the Software is furnished to do // so, subject to the following conditions: // The above copyright notice and this permission notice shall be included in all // copies or substantial portions of the Software. // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE // SOFTWARE. // ------------------------------------------------------------------------------ // ALTERNATIVE B - Public Domain (www.unlicense.org) // This is free and unencumbered software released into the public domain. // Anyone is free to copy, modify, publish, use, compile, sell, or distribute this // software, either in source code form or as a compiled binary, for any purpose, // commercial or non-commercial, and by any means. // In jurisdictions that recognize copyright laws, the author or authors of this // software dedicate any and all copyright interest in the software to the public // domain. We make this dedication for the benefit of the public at large and to // the detriment of our heirs and successors. We intend this dedication to be an // overt act of relinquishment in perpetuity of all present and future rights to // this software under copyright law. // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN // ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. // ------------------------------------------------------------------------------