From 38c6eeed269afb75791187f9ba353a9211716e70 Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Tue, 19 Feb 2019 14:27:21 +0100
Subject: [PATCH] [dxbc] Only emit depth clamp in fragment shader if necessary

We don't need this if the depth clip extension is supported
by the driver.
---
 src/dxbc/dxbc_compiler.cpp | 5 ++++-
 src/dxbc/dxbc_options.cpp  | 2 ++
 src/dxbc/dxbc_options.h    | 4 ++++
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/dxbc/dxbc_compiler.cpp b/src/dxbc/dxbc_compiler.cpp
index 638e720b..11569842 100644
--- a/src/dxbc/dxbc_compiler.cpp
+++ b/src/dxbc/dxbc_compiler.cpp
@@ -6601,7 +6601,10 @@ namespace dxvk {
     
     this->emitOutputSetup();
     this->emitOutputMapping();
-    this->emitOutputDepthClamp();
+
+    if (m_moduleInfo.options.useDepthClipWorkaround)
+      this->emitOutputDepthClamp();
+    
     this->emitFunctionEnd();
   }
   
diff --git a/src/dxbc/dxbc_options.cpp b/src/dxbc/dxbc_options.cpp
index 940119d4..3ec58c05 100644
--- a/src/dxbc/dxbc_options.cpp
+++ b/src/dxbc/dxbc_options.cpp
@@ -15,6 +15,8 @@ namespace dxvk {
     const DxvkDeviceFeatures& devFeatures = device->features();
     const DxvkDeviceInfo& devInfo = adapter->devicePropertiesExt();
     
+    useDepthClipWorkaround
+      = !devFeatures.extDepthClipEnable.depthClipEnable;
     useStorageImageReadWithoutFormat
       = devFeatures.core.features.shaderStorageImageReadWithoutFormat;
     useSubgroupOpsForEarlyDiscard
diff --git a/src/dxbc/dxbc_options.h b/src/dxbc/dxbc_options.h
index b569398f..ef332c16 100644
--- a/src/dxbc/dxbc_options.h
+++ b/src/dxbc/dxbc_options.h
@@ -10,6 +10,10 @@ namespace dxvk {
     DxbcOptions();
     DxbcOptions(const Rc<DxvkDevice>& device, const D3D11Options& options);
 
+    // Clamp oDepth in fragment shaders if the depth
+    // clip device feature is not supported
+    bool useDepthClipWorkaround = false;
+
     /// Use the ShaderImageReadWithoutFormat capability.
     bool useStorageImageReadWithoutFormat = false;