[D3D12] A bit of HLSL shader translator

src/xenia/gpu/hlsl_shader_translator.h

@@ -0,0 +1,72 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2018 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#ifndef XENIA_GPU_HLSL_SHADER_TRANSLATOR_H_
+#define XENIA_GPU_HLSL_SHADER_TRANSLATOR_H_
+
+#include <vector>
+
+#include "xenia/base/string_buffer.h"
+#include "xenia/gpu/shader_translator.h"
+
+namespace xe {
+namespace gpu {
+
+// For shader model 5_1 (Direct3D 12).
+class HlslShaderTranslator : public ShaderTranslator {
+ public:
+  HlslShaderTranslator();
+  ~HlslShaderTranslator() override;
+
+  enum class SRVType : uint32_t {
+    // 1D, 2D or stacked texture bound as a 2D array texture.
+    Texture2DArray,
+    // 3D texture (also has a 2D array view of the same fetch registers because
+    // tfetch3D is used for both stacked and 3D textures.
+    Texture3D,
+    // Cube texture.
+    TextureCube
+  };
+
+  struct SRVBinding {
+    SRVType type : 2;
+    // 0-31 for textures, 0-95 for vertex buffers.
+    uint32_t fetch_constant : 7;
+  };
+
+ protected:
+  void Reset() override;
+
+  void EmitTranslationError(const char* message) override;
+  void EmitUnimplementedTranslationError() override;
+
+ private:
+  void Indent();
+  void Unindent();
+
+  StringBuffer source_;
+  uint32_t depth_ = 0;
+  char depth_prefix_[16] = {0};
+
+  std::vector<SRVBinding> srv_bindings_;
+  // Finds or adds an SRV binding to the shader's SRV list, returns t# index.
+  uint32_t AddSRVBinding(SRVType type, uint32_t fetch_constant);
+
+  // Sampler index -> fetch constant index mapping.
+  // TODO(Triang3l): On binding tier 1 (Nvidia Fermi), there can't be more than
+  // 16 samplers in a shader. Hopefully no game uses so many.
+  uint32_t sampler_fetch_constants_[32];
+  uint32_t sampler_count_ = 0;
+  uint32_t AddSampler(uint32_t fetch_constant);
+};
+
+}  // namespace gpu
+}  // namespace xe
+
+#endif  // XENIA_GPU_HLSL_SHADER_TRANSLATOR_H_