From 4ce64bd8865bbb25baa25d622437c9258126c4d2 Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Sat, 24 Mar 2018 00:32:22 +0100
Subject: [PATCH] [dxbc] Do not emit per-vertex input block

Instead, we can let the normal input registers do their thing.
---
 src/dxbc/dxbc_compiler.cpp | 61 ++++++--------------------------------
 src/dxbc/dxbc_compiler.h   |  5 ----
 2 files changed, 9 insertions(+), 57 deletions(-)

diff --git a/src/dxbc/dxbc_compiler.cpp b/src/dxbc/dxbc_compiler.cpp
index a8ddbbdb..d835c6cd 100644
--- a/src/dxbc/dxbc_compiler.cpp
+++ b/src/dxbc/dxbc_compiler.cpp
@@ -585,7 +585,12 @@ namespace dxvk {
       m_interfaceSlots.inputSlots |= 1u << regIdx;
     } else if (sv != DxbcSystemValue::None) {
       // Add a new system value mapping if needed
-      m_vMappings.push_back({ regIdx, regMask, sv });
+      bool skipSv = sv == DxbcSystemValue::Position
+                 || sv == DxbcSystemValue::ClipDistance
+                 || sv == DxbcSystemValue::CullDistance;
+      
+      if (!skipSv || m_version.type() == DxbcProgramType::PixelShader)
+        m_vMappings.push_back({ regIdx, regMask, sv });
     }
   }
   
@@ -1071,11 +1076,7 @@ namespace dxvk {
     m_gs.inputPrimitive = ins.controls.primitive;
     m_module.setExecutionMode(m_entryPointId, mode);
     
-    const uint32_t vertexCount
-      = primitiveVertexCount(m_gs.inputPrimitive);
-    
-    emitDclInputArray(vertexCount);
-    emitDclInputPerVertex(vertexCount, "gs_vertex_in");
+    emitDclInputArray(primitiveVertexCount(m_gs.inputPrimitive));
   }
   
   
@@ -4919,33 +4920,8 @@ namespace dxvk {
           DxbcSystemValue         sv,
           DxbcRegMask             mask,
           uint32_t                vertexId) {
-    switch (sv) {
-      case DxbcSystemValue::Position: {
-        const std::array<uint32_t, 2> indices = {
-          m_module.consti32(vertexId),
-          m_module.consti32(PerVertex_Position),
-        };
-        
-        DxbcRegisterPointer ptrIn;
-        ptrIn.type.ctype  = DxbcScalarType::Float32;
-        ptrIn.type.ccount = 4;
-        
-        ptrIn.id = m_module.opAccessChain(
-          m_module.defPointerType(
-            getVectorTypeId(ptrIn.type),
-            spv::StorageClassInput),
-          m_perVertexIn,
-          indices.size(),
-          indices.data());
-        
-        return emitRegisterExtract(
-          emitValueLoad(ptrIn), mask);
-      } break;
-      
-      default:
-        throw DxvkError(str::format(
-          "DxbcCompiler: Unhandled GS SV input: ", sv));
-    }
+    throw DxvkError(str::format(
+      "DxbcCompiler: Unhandled GS SV input: ", sv));
   }
   
   
@@ -5538,25 +5514,6 @@ namespace dxvk {
   }
   
   
-  void DxbcCompiler::emitDclInputPerVertex(
-          uint32_t          vertexCount,
-    const char*             varName) {
-    uint32_t typeId = getPerVertexBlockId();
-    
-    if (vertexCount != 0) {
-      typeId = m_module.defArrayType(typeId,
-        m_module.constu32(vertexCount));
-    }
-    
-    const uint32_t ptrTypeId = m_module.defPointerType(
-      typeId, spv::StorageClassInput);
-    
-    m_perVertexIn = m_module.newVar(
-      ptrTypeId, spv::StorageClassInput);
-    m_module.setDebugName(m_perVertexIn, varName);
-  }
-  
-  
   DxbcCompilerHsControlPointPhase DxbcCompiler::emitNewHullShaderControlPointPhase() {
     uint32_t funTypeId = m_module.defFunctionType(
       m_module.defVoidType(), 0, nullptr);
diff --git a/src/dxbc/dxbc_compiler.h b/src/dxbc/dxbc_compiler.h
index 45fabccd..27fcdee5 100644
--- a/src/dxbc/dxbc_compiler.h
+++ b/src/dxbc/dxbc_compiler.h
@@ -390,7 +390,6 @@ namespace dxvk {
     ////////////////////////////////////////////////////
     // Per-vertex input and output blocks. Depending on
     // the shader stage, these may be declared as arrays.
-    uint32_t m_perVertexIn  = 0;
     uint32_t m_perVertexOut = 0;
     
     //////////////////////////////////////////////////
@@ -931,10 +930,6 @@ namespace dxvk {
     void emitDclInputArray(
             uint32_t          vertexCount);
     
-    void emitDclInputPerVertex(
-            uint32_t          vertexCount,
-      const char*             varName);
-    
     DxbcCompilerHsControlPointPhase emitNewHullShaderControlPointPhase();
     
     DxbcCompilerHsControlPointPhase emitNewHullShaderPassthroughPhase();