[dxvk] Optimized descriptor updates

src/dxvk/dxvk_cmdlist.cpp

@@ -105,9 +105,7 @@ namespace dxvk {
     VkDescriptorSet dset = m_descAlloc.alloc(descriptorLayout);
     
     // Write data to the descriptor set
-    // TODO recycle vector as a class member
-    std::vector<VkWriteDescriptorSet> descriptorWrites;
-    descriptorWrites.resize(descriptorCount);
+    std::array<VkWriteDescriptorSet, MaxNumResourceSlots> descriptorWrites;
     
     for (uint32_t i = 0; i < descriptorCount; i++) {
       auto& curr = descriptorWrites.at(i);
@@ -127,7 +125,7 @@ namespace dxvk {
     
     m_vkd->vkUpdateDescriptorSets(
       m_vkd->device(),
-      descriptorWrites.size(),
+      descriptorCount,
       descriptorWrites.data(),
       0, nullptr);
     

src/dxvk/dxvk_cmdlist.h

@@ -4,6 +4,7 @@
 
 #include "dxvk_descriptor.h"
 #include "dxvk_lifetime.h"
+#include "dxvk_limits.h"
 #include "dxvk_pipelayout.h"
 #include "dxvk_staging.h"
 

src/dxvk/dxvk_context.cpp

@@ -866,8 +866,6 @@ namespace dxvk {
       // resource was marked as dirty after invalidation
       // TODO move this into a separate method so that
       // compute can use this code as well
-      std::vector<DxvkDescriptorInfo> descriptors;
-      
       for (uint32_t i = 0; i < layout->bindingCount(); i++) {
         const uint32_t slot = layout->binding(i).slot;
         const auto& res = m_gResources.getShaderResource(slot);
@@ -897,7 +895,7 @@ namespace dxvk {
           descriptor.buffer = res.bufferSlice.descriptorInfo();
         }
         
-        descriptors.push_back(descriptor);
+        descriptors.at(i) = descriptor;
       }
       
       m_cmd->bindResourceDescriptors(

src/dxvk/dxvk_context.h

@@ -418,6 +418,8 @@ namespace dxvk {
     DxvkShaderResourceSlots m_cResources = {  256 };
     DxvkShaderResourceSlots m_gResources = { 1024 };
     
+    std::array<DxvkDescriptorInfo, MaxNumResourceSlots> descriptors;
+    
     void renderPassBegin();
     void renderPassEnd();
     

src/dxvk/dxvk_limits.h

@@ -10,7 +10,7 @@ namespace dxvk {
     MaxNumVertexBindings        =   32,
     MaxNumOutputStreams         =    4,
     MaxNumViewports             =   16,
-    MaxNumResourceSlots         = 4096,
+    MaxNumResourceSlots         = 1024,
   };
   
 }