Support vertex offset mode with new D3D12_VERTEX_BUFFER_VIEW

In vertex offset mode. we will use D3D12_VERTEX_BUFFER_VIEW to replace SRD, the address and size fields are already in the right place. We only need to get stride and fill the fourth DWORD. Then we calculate offset with stride and vertex index. For Uber fetch shader, SRD will be updated in driver.
GPUOpen-Drivers · Nov 27, 2023 · 950c3a6 · 950c3a6
1 parent 0b15602
commit 950c3a6
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Showing 10 changed files with 164 additions and 91 deletions.
diff --git a/include/vkgcDefs.h b/include/vkgcDefs.h
@@ -49,7 +49,7 @@
 #define LLPC_INTERFACE_MAJOR_VERSION 70
 
 /// LLPC minor interface version.
-#define LLPC_INTERFACE_MINOR_VERSION 1
+#define LLPC_INTERFACE_MINOR_VERSION 2
 
 #ifndef LLPC_CLIENT_INTERFACE_MAJOR_VERSION
 #error LLPC client version is not defined
@@ -80,6 +80,7 @@
 //  %Version History
 //  | %Version | Change Description                                                                                    |
 //  | -------- | ----------------------------------------------------------------------------------------------------- |
+//  |     70.2 | Add useSoftwareVertexBufferDescriptors to GraphicsPipelineBuildInfo                                   |
 //  |     70.1 | Add cpsFlags to RayTracingPipelineBuildInfo                                                           |
 //  |     70.0 | Add enablePrimGeneratedQuery to PipelineOptions                                                       |
 //  |     69.1 | Add useBarycentric to ShaderModuleUsage                                                               |
@@ -1361,14 +1362,15 @@ struct GraphicsPipelineBuildInfo {
     ColorTarget target[MaxColorTargets]; ///< Per-MRT color target info
   } cbState;                             ///< Color target state
 
-  NggState nggState;            ///< NGG state used for tuning and debugging
-  PipelineOptions options;      ///< Per pipeline tuning/debugging options
-  bool unlinked;                ///< True to build an "unlinked" half-pipeline ELF
-  bool dynamicVertexStride;     ///< Dynamic Vertex input Stride is enabled.
-  bool enableUberFetchShader;   ///< Use uber fetch shader
-  bool enableColorExportShader; ///< Explicitly build color export shader, UnlinkedStageFragment elf will
-                                ///  return extra meta data.
-  bool enableEarlyCompile;      ///< Whether enable early compile
+  NggState nggState;                       ///< NGG state used for tuning and debugging
+  PipelineOptions options;                 ///< Per pipeline tuning/debugging options
+  bool unlinked;                           ///< True to build an "unlinked" half-pipeline ELF
+  bool dynamicVertexStride;                ///< Dynamic Vertex input Stride is enabled.
+  bool enableUberFetchShader;              ///< Use uber fetch shader
+  bool enableColorExportShader;            ///< Explicitly build color export shader, UnlinkedStageFragment elf will
+                                           ///  return extra meta data.
+  bool enableEarlyCompile;                 ///< Whether enable early compile
+  bool useSoftwareVertexBufferDescriptors; ///< Use software vertex buffer descriptors to structure SRD.
 #if LLPC_CLIENT_INTERFACE_MAJOR_VERSION < 62
   BinaryData shaderLibrary; ///< SPIR-V library binary data
 #endif

diff --git a/lgc/elfLinker/FetchShader.cpp b/lgc/elfLinker/FetchShader.cpp
@@ -101,7 +101,8 @@ Module *FetchShader::generate() {
 //
 // @param [in/out] fetchFunc : The function for the fetch shader.
 void FetchShader::generateFetchShaderBody(Function *fetchFunc) { // Process each vertex input.
-  std::unique_ptr<VertexFetch> vertexFetch(VertexFetch::create(m_lgcContext));
+  std::unique_ptr<VertexFetch> vertexFetch(
+      VertexFetch::create(m_lgcContext, m_pipelineState->getOptions().useSoftwareVertexBufferDescriptors));
   auto ret = cast<ReturnInst>(fetchFunc->back().getTerminator());
   BuilderImpl builder(m_pipelineState);
   builder.SetInsertPoint(ret);

diff --git a/lgc/include/lgc/patch/VertexFetch.h b/lgc/include/lgc/patch/VertexFetch.h
@@ -46,7 +46,7 @@ class VertexFetch {
   virtual ~VertexFetch() {}
 
   // Create a VertexFetch
-  static VertexFetch *create(LgcContext *lgcContext);
+  static VertexFetch *create(LgcContext *lgcContext, bool useSoftwareVertexBufferDescriptors);
 
   // Generate code to fetch a vertex value
   virtual llvm::Value *fetchVertex(llvm::Type *inputTy, const VertexInputDescription *description, unsigned location,

diff --git a/lgc/interface/lgc/Pipeline.h b/lgc/interface/lgc/Pipeline.h
@@ -178,10 +178,11 @@ union Options {
     bool fragCoordUsesInterpLoc;  // Determining fragCoord use InterpLoc
     bool disableSampleMask;       // Disable export of sample mask from PS
     unsigned reserved20;
-    RayTracingIndirectMode rtIndirectMode; // Ray tracing indirect mode
-    bool enablePrimGeneratedQuery;         // Whether to enable primitive generated counter
-    bool enableFragColor;                  // If enabled, do frag color broadcast
-    unsigned cpsFlags;                     // CPS feature flags
+    RayTracingIndirectMode rtIndirectMode;   // Ray tracing indirect mode
+    bool enablePrimGeneratedQuery;           // Whether to enable primitive generated counter
+    bool enableFragColor;                    // If enabled, do frag color broadcast
+    bool useSoftwareVertexBufferDescriptors; // Use software vertex buffer descriptors to structure SRD.
+    unsigned cpsFlags;                       // CPS feature flags
   };
 };
 static_assert(sizeof(Options) == sizeof(Options::u32All));