From 43622f463db2a750b3148884e35dcaa5635e691d Mon Sep 17 00:00:00 2001
From: CamilleLaVey <camillelavey99@gmail.com>
Date: Wed, 16 Sep 2026 16:59:20 -0400
Subject: [PATCH] A test for a corrupted unswizzled textures

---
 src/video_core/host_shaders/astc_decoder.comp | 26 +++++++------------
 .../renderer_vulkan/vk_texture_cache.cpp      |  6 ++++-
 2 files changed, 14 insertions(+), 18 deletions(-)

diff --git a/src/video_core/host_shaders/astc_decoder.comp b/src/video_core/host_shaders/astc_decoder.comp
index 58dccb545f..9a3954ca21 100644
--- a/src/video_core/host_shaders/astc_decoder.comp
+++ b/src/video_core/host_shaders/astc_decoder.comp
@@ -164,27 +164,19 @@ uint FastReplicateTo8(uint value, uint num_bits) {
     return ReplicateBits(value, num_bits, 8);
 }
 
+const uint REPLICATE_TO_6_ODD_HALVES = ((63u >> 1u) << 5u) | ((21u >> 1u) << 10u) |
+                                       ((9u >> 1u) << 15u) | ((17u >> 1u) << 20u) |
+                                       ((33u >> 1u) << 25u);
+const uint REPLICATE_TO_6_SHIFTS = (2u << 16u) | (4u << 20u);
+
 uint FastReplicateTo6(uint value, uint num_bits) {
-    if (num_bits == 0) {
-        return 0;
-    }
-    if (num_bits >= 6) {
+    if (num_bits >= 6u) {
         return value;
     }
     const uint v = value & ((1u << num_bits) - 1u);
-    if (num_bits == 1) {
-        return v * 63u;
-    }
-    if (num_bits == 2) {
-        return v * 21u;
-    }
-    if (num_bits == 3) {
-        return v * 9u;
-    }
-    if (num_bits == 4) {
-        return (v << 2u) | (v >> 2u);
-    }
-    return (v << 1u) | (v >> 4u);
+    const uint c = ((REPLICATE_TO_6_ODD_HALVES >> (num_bits * 5u)) & 0x1fu) * 2u + 1u;
+    const uint s = (REPLICATE_TO_6_SHIFTS >> (num_bits * 4u)) & 0xfu;
+    return (v * c) >> s;
 }
 
 uint Div3Floor(uint v) {
diff --git a/src/video_core/renderer_vulkan/vk_texture_cache.cpp b/src/video_core/renderer_vulkan/vk_texture_cache.cpp
index caff739187..ff1ab0bf2c 100644
--- a/src/video_core/renderer_vulkan/vk_texture_cache.cpp
+++ b/src/video_core/renderer_vulkan/vk_texture_cache.cpp
@@ -57,7 +57,8 @@ using VideoCore::Surface::SurfaceType;
 namespace {
 constexpr bool ENABLE_MSAA_TILER_RESOLVE = true;
 constexpr bool ENABLE_MSAA_RESOLVE_CONSUME = true;
-constexpr bool ENABLE_ACCELERATED_UNSWIZZLE = false;
+constexpr bool ENABLE_ACCELERATED_UNSWIZZLE = true;
+constexpr bool ENABLE_ACCELERATED_UNSWIZZLE_DISPATCH = false;
 constexpr bool ENABLE_MSAA_COLOR_DISCARD = true;
 constexpr bool ENABLE_MSAA_DEPTH_STENCIL_DISCARD = true;
 
@@ -207,6 +208,9 @@ constexpr VkBorderColor ConvertBorderColor(const std::array<float, 4>& color) {
 }
 
 [[nodiscard]] bool WillUseAcceleratedUnswizzle(const Device& device, const ImageInfo& info) {
+    if (!ENABLE_ACCELERATED_UNSWIZZLE_DISPATCH) {
+        return false;
+    }
     switch (info.type) {
     case ImageType::e2D:
     case ImageType::e3D: