initial checkin of SkSL compiler

src/gpu/vk/GrVkGpu.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrVkGpu_DEFINED
 #define GrVkGpu_DEFINED
 
+#define USE_SKSL 1
+
 #include "GrGpu.h"
 #include "GrGpuFactory.h"
 #include "vk/GrVkBackendContext.h"
 #include "GrVkCaps.h"
 #include "GrVkIndexBuffer.h"
 #include "GrVkMemory.h"
 #include "GrVkResourceProvider.h"
 #include "GrVkVertexBuffer.h"
 #include "GrVkUtil.h"
 
+#if USE_SKSL
+namespace SkSL {
+    class Compiler;
+}
+#else
 #include "shaderc/shaderc.h"
+#endif
+
 #include "vk/GrVkDefines.h"
 
 class GrPipeline;
 class GrNonInstancedMesh;
 
 class GrVkBufferImpl;
 class GrVkPipeline;
 class GrVkPipelineState;
 class GrVkPrimaryCommandBuffer;
 class GrVkRenderPass;
@@ skipping 72 matching lines @@
                           VkMemoryBarrier* barrier) const;
     void addBufferMemoryBarrier(VkPipelineStageFlags srcStageMask,
                                 VkPipelineStageFlags dstStageMask,
                                 bool byRegion,
                                 VkBufferMemoryBarrier* barrier) const;
     void addImageMemoryBarrier(VkPipelineStageFlags srcStageMask,
                                VkPipelineStageFlags dstStageMask,
                                bool byRegion,
                                VkImageMemoryBarrier* barrier) const;
 
+#if USE_SKSL
+    SkSL::Compiler* shaderCompiler() const {
+        return fCompiler;
+    }
+#else
     shaderc_compiler_t shadercCompiler() const {
         return fCompiler;
     }
+#endif
 
     void submitSecondaryCommandBuffer(const GrVkSecondaryCommandBuffer*,
                                       const GrVkRenderPass*,
                                       const VkClearValue*,
                                       GrVkRenderTarget*,
                                       const SkIRect& bounds);
 
     void finishDrawTarget() override;
 
     void generateMipmap(GrVkTexture* tex) const;
@@ skipping 106 matching lines @@
     GrVkPrimaryCommandBuffer*              fCurrentCmdBuffer;
     VkPhysicalDeviceMemoryProperties       fPhysDevMemProps;
 
     SkAutoTDelete<GrVkHeap>                fHeaps[kHeapCount];
 
 #ifdef ENABLE_VK_LAYERS
     // For reporting validation layer errors
     VkDebugReportCallbackEXT               fCallback;
 #endif
 
+#if USE_SKSL
+    SkSL::Compiler* fCompiler;
+#else
     // Shaderc compiler used for compiling glsl in spirv. We only want to create the compiler once
     // since there is significant overhead to the first compile of any compiler.
     shaderc_compiler_t fCompiler;
-
+#endif
 
     typedef GrGpu INHERITED;
 };
 
 #endif