From 08da6d8ca4a93efc95c984fa78f0001a9d3bf4b6 Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Mon, 25 Jul 2022 15:58:03 +0200
Subject: [PATCH] [dxbc] Bound-check mip level for resinfo instruction

---
 src/dxbc/dxbc_compiler.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/dxbc/dxbc_compiler.cpp b/src/dxbc/dxbc_compiler.cpp
index ad393d554..70aaa2e3f 100644
--- a/src/dxbc/dxbc_compiler.cpp
+++ b/src/dxbc/dxbc_compiler.cpp
@@ -3077,7 +3077,14 @@ namespace dxvk {
     // result into a four-component vector later.
     DxbcRegisterValue imageSize   = emitQueryTextureSize(ins.src[1], mipLod);
     DxbcRegisterValue imageLevels = emitQueryTextureLods(ins.src[1]);
-    
+
+    // If the mip level is out of bounds, D3D requires us to return
+    // zero before applying modifiers, whereas SPIR-V is undefined,
+    // so we need to fix it up manually here.
+    imageSize.id = m_module.opSelect(getVectorTypeId(imageSize.type),
+      m_module.opULessThan(m_module.defBoolType(), mipLod.id, imageLevels.id),
+      imageSize.id, emitBuildZeroVector(imageSize.type).id);
+
     // Convert intermediates to the requested type
     if (returnType == DxbcScalarType::Float32) {
       imageSize.type.ctype = DxbcScalarType::Float32;