From f69c5e4c4e6426077136964b97922ca768675b89 Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Fri, 16 Nov 2018 19:47:34 +0100
Subject: [PATCH] [dxbc] Emit Index decoration for pixel shader outputs

Simplifies shader patching when dual-source blending is used.
---
 src/dxbc/dxbc_compiler.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/dxbc/dxbc_compiler.cpp b/src/dxbc/dxbc_compiler.cpp
index fdf66c177..e42e3d97e 100644
--- a/src/dxbc/dxbc_compiler.cpp
+++ b/src/dxbc/dxbc_compiler.cpp
@@ -719,6 +719,10 @@ namespace dxvk {
       if (info.sclass == spv::StorageClassOutput) {
         m_module.decorateLocation(varId, regIdx);
         m_entryPointInterfaces.push_back(varId);
+
+        // Add index decoration for potential dual-source blending
+        if (m_programInfo.type() == DxbcProgramType::PixelShader)
+          m_module.decorateIndex(varId, 0);
       }
       
       m_oRegs.at(regIdx) = { regType, varId };