1 /* 2 * Copyright 2016 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #ifndef SkRasterPipeline_DEFINED 9 #define SkRasterPipeline_DEFINED 10 11 #include "include/core/SkColor.h" 12 #include "include/core/SkTypes.h" 13 #include "include/private/base/SkMacros.h" 14 #include "include/private/base/SkSpan_impl.h" 15 #include "include/private/base/SkTArray.h" 16 #include "src/base/SkArenaAlloc.h" 17 #include "src/core/SkRasterPipelineOpContexts.h" 18 19 #include <cstddef> 20 #include <cstdint> 21 #include <functional> 22 23 class SkMatrix; 24 enum class SkRasterPipelineOp; 25 enum SkColorType : int; 26 struct SkImageInfo; 27 struct skcms_TransferFunction; 28 29 #if __has_cpp_attribute(clang::musttail) && !defined(__EMSCRIPTEN__) && !defined(SK_CPU_ARM32) && \ 30 !defined(SK_CPU_LOONGARCH) && !defined(SK_CPU_PPC) && !defined(_WIN32) 31 // [[clang::musttail]] is disabled for the Android version of Skia running on Windows as it 32 // causes crashes (This is probably related to http://crbug.com/1505442). 33 #define SK_HAS_MUSTTAIL 1 34 #else 35 #define SK_HAS_MUSTTAIL 0 36 #endif 37 38 /** 39 * SkRasterPipeline provides a cheap way to chain together a pixel processing pipeline. 40 * 41 * It's particularly designed for situations where the potential pipeline is extremely 42 * combinatoric: {N dst formats} x {M source formats} x {K mask formats} x {C transfer modes} ... 43 * No one wants to write specialized routines for all those combinations, and if we did, we'd 44 * end up bloating our code size dramatically. SkRasterPipeline stages can be chained together 45 * at runtime, so we can scale this problem linearly rather than combinatorically. 46 * 47 * Each stage is represented by a function conforming to a common interface and by an 48 * arbitrary context pointer. The stage function arguments and calling convention are 49 * designed to maximize the amount of data we can pass along the pipeline cheaply, and 50 * vary depending on CPU feature detection. 51 */ 52 53 // Raster pipeline programs are stored as a contiguous array of SkRasterPipelineStages. 54 SK_BEGIN_REQUIRE_DENSE 55 struct SkRasterPipelineStage { 56 // `fn` holds a function pointer from `ops_lowp` or `ops_highp` in SkOpts.cpp. These functions 57 // correspond to operations from the SkRasterPipelineOp enum in SkRasterPipelineOpList.h. The 58 // exact function pointer type varies depending on architecture (specifically, look for `using 59 // Stage =` in SkRasterPipeline_opts.h). 60 void (*fn)(); 61 62 // `ctx` holds data used by the stage function. 63 // Most context structures are declared in SkRasterPipelineOpContexts.h, and have names ending 64 // in Ctx (e.g. "SkRasterPipeline_SamplerCtx"). Some Raster Pipeline stages pack non-pointer 65 // data into this field using `SkRPCtxUtils::Pack`. 66 void* ctx; 67 }; 68 SK_END_REQUIRE_DENSE 69 70 class SkRasterPipeline { 71 public: 72 explicit SkRasterPipeline(SkArenaAlloc*); 73 74 SkRasterPipeline(const SkRasterPipeline&) = delete; 75 SkRasterPipeline(SkRasterPipeline&&) = default; 76 77 SkRasterPipeline& operator=(const SkRasterPipeline&) = delete; 78 SkRasterPipeline& operator=(SkRasterPipeline&&) = default; 79 80 void reset(); 81 82 void append(SkRasterPipelineOp, void* = nullptr); append(SkRasterPipelineOp op,const void * ctx)83 void append(SkRasterPipelineOp op, const void* ctx) { this->append(op,const_cast<void*>(ctx)); } 84 void append(SkRasterPipelineOp, uintptr_t ctx); 85 86 // Append all stages to this pipeline. 87 void extend(const SkRasterPipeline&); 88 89 // Runs the pipeline in 2d from (x,y) inclusive to (x+w,y+h) exclusive. 90 void run(size_t x, size_t y, size_t w, size_t h) const; 91 92 // Allocates a thunk which amortizes run() setup cost in alloc. 93 std::function<void(size_t, size_t, size_t, size_t)> compile() const; 94 95 // Callers can inspect the stage list for debugging purposes. 96 struct StageList { 97 StageList* prev; 98 SkRasterPipelineOp stage; 99 void* ctx; 100 }; 101 102 static const char* GetOpName(SkRasterPipelineOp op); getStageList()103 const StageList* getStageList() const { return fStages; } getNumStages()104 int getNumStages() const { return fNumStages; } 105 106 // Prints the entire StageList using SkDebugf. 107 void dump() const; 108 109 // Appends a stage for the specified matrix. 110 // Tries to optimize the stage by analyzing the type of matrix. 111 void appendMatrix(SkArenaAlloc*, const SkMatrix&); 112 113 // Appends a stage for a constant uniform color. 114 // Tries to optimize the stage based on the color. 115 void appendConstantColor(SkArenaAlloc*, const float rgba[4]); 116 appendConstantColor(SkArenaAlloc * alloc,const SkColor4f & color)117 void appendConstantColor(SkArenaAlloc* alloc, const SkColor4f& color) { 118 this->appendConstantColor(alloc, color.vec()); 119 } 120 121 // Like appendConstantColor() but only affecting r,g,b, ignoring the alpha channel. 122 void appendSetRGB(SkArenaAlloc*, const float rgb[3]); 123 appendSetRGB(SkArenaAlloc * alloc,const SkColor4f & color)124 void appendSetRGB(SkArenaAlloc* alloc, const SkColor4f& color) { 125 this->appendSetRGB(alloc, color.vec()); 126 } 127 128 void appendLoad (SkColorType, const SkRasterPipeline_MemoryCtx*); 129 void appendLoadDst(SkColorType, const SkRasterPipeline_MemoryCtx*); 130 void appendStore (SkColorType, const SkRasterPipeline_MemoryCtx*); 131 132 void appendClampIfNormalized(const SkImageInfo&); 133 134 void appendTransferFunction(const skcms_TransferFunction&); 135 136 void appendStackRewind(); 137 empty()138 bool empty() const { return fStages == nullptr; } 139 140 private: 141 bool buildLowpPipeline(SkRasterPipelineStage* ip) const; 142 void buildHighpPipeline(SkRasterPipelineStage* ip) const; 143 144 using StartPipelineFn = void (*)(size_t, size_t, size_t, size_t, 145 SkRasterPipelineStage* program, 146 SkSpan<SkRasterPipeline_MemoryCtxPatch>, 147 uint8_t*); 148 StartPipelineFn buildPipeline(SkRasterPipelineStage*) const; 149 150 void uncheckedAppend(SkRasterPipelineOp, void*); 151 int stagesNeeded() const; 152 153 void addMemoryContext(SkRasterPipeline_MemoryCtx*, int bytesPerPixel, bool load, bool store); 154 uint8_t* tailPointer(); 155 156 SkArenaAlloc* fAlloc; 157 SkRasterPipeline_RewindCtx* fRewindCtx; 158 StageList* fStages; 159 uint8_t* fTailPointer; 160 int fNumStages; 161 162 // Only 1 in 2 million CPU-backend pipelines used more than two MemoryCtxs. 163 // (See the comment in SkRasterPipelineOpContexts.h for how MemoryCtx patching works) 164 skia_private::STArray<2, SkRasterPipeline_MemoryCtxInfo> fMemoryCtxInfos; 165 }; 166 167 template <size_t bytes> 168 class SkRasterPipeline_ : public SkRasterPipeline { 169 public: SkRasterPipeline_()170 SkRasterPipeline_() 171 : SkRasterPipeline(&fBuiltinAlloc) {} 172 173 private: 174 SkSTArenaAlloc<bytes> fBuiltinAlloc; 175 }; 176 177 178 #endif//SkRasterPipeline_DEFINED 179