fix(agc): reuse a recycled descriptor set only for a table of its own size

core/libs/prx/libSceAgcDriver/Graphics/include/ShaderResources.hpp

@@ -127,7 +127,7 @@ class DescriptorCache {
     std::vector<Pool> pools;
     std::vector<Pool> updateAfterBindPools;
     std::vector<VkDescriptorPool> dedicated;
-    std::unordered_map<VkDescriptorSetLayout, std::vector<SetAllocation>> recycled;
+    std::map<std::pair<VkDescriptorSetLayout, std::uint32_t>, std::vector<SetAllocation>> recycled;
     std::vector<SetAllocation> kept;
     Stats stats;
 };

core/libs/prx/libSceAgcDriver/Graphics/src/ShaderResources.cpp

@@ -3856,7 +3856,7 @@ DescriptorCache::SetAllocation DescriptorCache::Allocate(VkDescriptorSetLayout l
         if (result == VK_SUCCESS) {
             ++stats.sets;
             ++pool.liveSets;
-            return {set, pool.handle, index - 1, updateAfterBind};
+            return {set, pool.handle, index - 1, updateAfterBind, VK_NULL_HANDLE, {}, variableCount, {}};
         }
         if (result != VK_ERROR_OUT_OF_POOL_MEMORY && result != VK_ERROR_FRAGMENTED_POOL) Check(result, "vkAllocateDescriptorSets");
         pool.exhausted = true;
@@ -3877,13 +3877,13 @@ DescriptorCache::SetAllocation DescriptorCache::Allocate(VkDescriptorSetLayout l
     Check(allocate(context.device, &allocation, &set), "vkAllocateDescriptorSets");
     chain.back().liveSets = 1;
     ++stats.sets;
-    return {set, pool, chain.size() - 1, updateAfterBind};
+    return {set, pool, chain.size() - 1, updateAfterBind, VK_NULL_HANDLE, {}, variableCount, {}};
 }
 
 DescriptorCache::SetAllocation DescriptorCache::AllocateRewritten(VkDescriptorSetLayout layout, std::span<const VkDescriptorPoolSize> sizes, bool updateAfterBind, std::optional<std::uint32_t> variableCount) {
     {
         std::lock_guard lock(mutex);
-        if (const auto found = recycled.find(layout); found != recycled.end() && !found->second.empty()) {
+        if (const auto found = recycled.find({layout, variableCount.value_or(0u)}); found != recycled.end() && !found->second.empty()) {
             const auto allocation = found->second.back();
             found->second.pop_back();
             return allocation;
@@ -3897,7 +3897,7 @@ void DescriptorCache::Recycle(VkDescriptorSetLayout layout, const SetAllocation&
     {
         std::lock_guard lock(mutex);
         try {
-            auto& list = recycled[layout];
+            auto& list = recycled[{layout, allocation.variableCount.value_or(0u)}];
             if (list.size() < 4096) {
                 list.push_back(allocation);
                 return;

core/libs/prx/libSceAgcDriver/tests/Graphics.cpp

@@ -5591,6 +5591,15 @@ void descriptorCacheTests() {
         const auto reused = cache.Allocate(fittingLayout, fitting, true, 0u);
         Require(reused.pool == chained.pool && mock.variableDescriptorCount == 0u, "reusing an update-after-bind pool lost an empty variable image table");
         cache.Free(reused);
+        const auto rewritten = cache.AllocateRewritten(fittingLayout, fitting, true, 3u);
+        cache.Recycle(fittingLayout, rewritten);
+        const std::array<VkDescriptorPoolSize, 2> grown{{{VK_DESCRIPTOR_TYPE_STORAGE_BUFFER, 17}, {VK_DESCRIPTOR_TYPE_SAMPLED_IMAGE, 5}}};
+        const auto larger = cache.AllocateRewritten(fittingLayout, grown, true, 5u);
+        Require(larger.set != rewritten.set && mock.variableDescriptorCount == 5u, "a recycled descriptor set served a larger variable image table than it was allocated for");
+        const auto same = cache.AllocateRewritten(fittingLayout, fitting, true, 3u);
+        Require(same.set == rewritten.set, "a recycled descriptor set was not reused for a variable image table of its own size");
+        cache.Free(larger);
+        cache.Free(same);
         expectFailure([&] { cache.Allocate(fittingLayout, fitting, false, 3u); }, "descriptor set exceeds the device's per-set descriptor limit");
     }
     Require(mock.live == 0, "the combined descriptor cache leaked a pool or layout");