[dxbc] Retrieve icb data directly from shader module

src/d3d11/d3d11_shader.cpp

@@ -59,13 +59,13 @@ namespace dxvk {
     }
     
     // Create shader constant buffer if necessary
-    const DxvkShaderCreateInfo& shaderInfo = m_shader->info();
+    auto icb = module.icbInfo();
 
-    if (shaderInfo.uniformSize) {
+    if (icb.size) {
-      DxvkBufferCreateInfo info;
+      DxvkBufferCreateInfo info = { };
-      info.size   = shaderInfo.uniformSize;
+      info.size   = align(icb.size, 256u);
       info.usage  = VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT;
-      info.stages = util::pipelineStages(shaderInfo.stage);
+      info.stages = util::pipelineStages(m_shader->info().stage);
       info.access = VK_ACCESS_UNIFORM_READ_BIT;
       info.debugName = "Icb";
       
@@ -75,7 +75,8 @@ namespace dxvk {
         | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT;
       
       m_buffer = pDevice->GetDXVKDevice()->createBuffer(info, memFlags);
-      std::memcpy(m_buffer->mapPtr(0), shaderInfo.uniformData, shaderInfo.uniformSize);
+      std::memcpy(m_buffer->mapPtr(0), icb.data, icb.size);
+      std::memset(m_buffer->mapPtr(icb.size), 0, info.size - icb.size);
     }
 
     pDevice->GetDXVKDevice()->registerShader(m_shader);

src/dxbc/dxbc_compiler.cpp

@@ -241,8 +241,6 @@ namespace dxvk {
     info.bindings = m_bindings.data();
     info.inputMask = m_inputMask;
     info.outputMask = m_outputMask;
-    info.uniformSize = m_icbData.size() * sizeof(uint32_t);
-    info.uniformData = reinterpret_cast<const char*>(m_icbData.data());
     info.pushConstStages = VK_SHADER_STAGE_FRAGMENT_BIT;
     info.pushConstSize = sizeof(DxbcPushConstants);
     info.outputTopology = m_outputTopology;

src/dxbc/dxbc_compiler.h

@@ -173,8 +173,8 @@ namespace dxvk {
 
     bool needsOutputSetup = false;
   };
-  
+
-  
+
   /**
    * \brief Pixel shader-specific structure
    */
@@ -404,6 +404,17 @@ namespace dxvk {
      * \returns The final shader object
      */
     Rc<DxvkShader> finalize();
+
+    /**
+     * \brief Extracts immediate constant buffer data
+     *
+     * Only defined if the ICB needs to be backed by a
+     * uniform buffer.
+     * \returns Immediate constant buffer data
+     */
+    std::vector<uint32_t> getIcbData() const {
+      return std::move(m_icbData);
+    }
     
   private:
     

src/dxbc/dxbc_module.cpp

@@ -65,6 +65,8 @@ namespace dxvk {
     
     this->runCompiler(compiler, m_shexChunk->slice());
 
+    m_icb = compiler.getIcbData();
+
     return compiler.finalize();
   }
   

src/dxbc/dxbc_module.h

@@ -18,6 +18,15 @@ namespace dxvk {
   class DxbcAnalyzer;
   class DxbcCompiler;
   
+  /**
+   * \brief Immediate constant buffer properties
+   */
+  struct DxbcIcbInfo {
+    size_t      size = 0u;
+    const void* data = nullptr;
+  };
+
+
   /**
    * \brief DXBC shader module
    * 
@@ -52,6 +61,19 @@ namespace dxvk {
       return m_bindings;
     }
 
+    /**
+     * \brief Retrieves immediate constant buffer info
+     *
+     * Only valid after successfully compiling the shader.
+     * \returns Immediate constant buffer data
+     */
+    DxbcIcbInfo icbInfo() const {
+      DxbcIcbInfo result = { };
+      result.size = m_icb.size() * sizeof(uint32_t);
+      result.data = m_icb.data();
+      return result;
+    }
+
     /**
      * \brief Input and output signature chunks
      * 
@@ -86,7 +108,7 @@ namespace dxvk {
     Rc<DxvkShader> compilePassthroughShader(
       const DxbcModuleInfo& moduleInfo,
       const std::string&    fileName) const;
-    
+
   private:
     
     DxbcHeader   m_header;
@@ -96,6 +118,8 @@ namespace dxvk {
     Rc<DxbcIsgn> m_psgnChunk;
     Rc<DxbcShex> m_shexChunk;
 
+    std::vector<uint32_t> m_icb;
+
     std::optional<DxbcBindingMask> m_bindings;
     
     void runAnalyzer(