Vulkan: De-duplicate pipelines when storing cache

The new variety of renderpasses with different transitions causes
duplication. Hopefully drivers are smart enough to re-use work
between similar pipelines as much as possible...

Common/Vulkan/VulkanContext.h

@@ -135,10 +135,11 @@ public:
 	bool EnableDeviceExtension(const char *extension);
 	VkResult CreateDevice();
 
-	const std::string &InitError() { return init_error_; }
+	const std::string &InitError() const { return init_error_; }
 
-	VkDevice GetDevice() { return device_; }
-	VkInstance GetInstance() { return instance_; }
+	VkDevice GetDevice() const { return device_; }
+	VkInstance GetInstance() const { return instance_; }
+	uint32_t GetFlags() const { return flags_; }
 
 	VulkanDeleteList &Delete() { return globalDeleteList_; }
 

Common/Vulkan/VulkanImage.cpp

@@ -58,6 +58,12 @@ bool VulkanTexture::CreateDirect(VkCommandBuffer cmd, int w, int h, int numMips,
 		image_create_info.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
 	}
 
+	// The graphics debugger always "needs" TRANSFER_SRC but in practice doesn't matter - 
+	// unless validation is on. So let's only force it on when being validated, for now.
+	if (vulkan_->GetFlags() & VULKAN_FLAG_VALIDATE) {
+		image_create_info.usage |= VK_IMAGE_USAGE_TRANSFER_SRC_BIT;
+	}
+
 	VkResult res = vkCreateImage(vulkan_->GetDevice(), &image_create_info, NULL, &image_);
 	if (res != VK_SUCCESS) {
 		_assert_(res == VK_ERROR_OUT_OF_HOST_MEMORY || res == VK_ERROR_OUT_OF_DEVICE_MEMORY || res == VK_ERROR_TOO_MANY_OBJECTS);

GPU/Vulkan/PipelineManagerVulkan.cpp

@@ -1,5 +1,6 @@
 #include <cstring>
 #include <memory>
+#include <set>
 
 #include "profiler/profiler.h"
 
@@ -526,12 +527,14 @@ void PipelineManagerVulkan::SaveCache(FILE *file, bool saveRawPipelineCache, Sha
 	}
 
 	size_t seekPosOnFailure = ftell(file);
-	// Write the number of pipelines.
-	size = (uint32_t)pipelines_.size();
-	fwrite(&size, sizeof(size), 1, file);
 
 	bool failed = false;
 	int count = 0;
+	// Since we don't include the full pipeline key, there can be duplicates,
+	// caused by things like switching from buffered to non-buffered rendering.
+	// Make sure the set of pipelines we write is "unique".
+	std::set<StoredVulkanPipelineKey> keys;
+
 	pipelines_.Iterate([&](const VulkanPipelineKey &pkey, VulkanPipeline *value) {
 		if (failed)
 			return;
@@ -550,10 +553,18 @@ void PipelineManagerVulkan::SaveCache(FILE *file, bool saveRawPipelineCache, Sha
 			// NOTE: This is not a vtype, but a decoded vertex format.
 			key.vtxFmtId = pkey.vtxFmtId;
 		}
-		fwrite(&key, sizeof(key), 1, file);
-		count++;
+		keys.insert(key);
 	});
 
+	// Write the number of pipelines.
+	size = (uint32_t)keys.size();
+	fwrite(&size, sizeof(size), 1, file);
+
+	// Write the pipelines.
+	for (auto &key : keys) {
+		fwrite(&key, sizeof(key), 1, file);
+	}
+
 	if (failed) {
 		ERROR_LOG(G3D, "Failed to write pipeline cache, some shader was missing");
 		// Write a zero in the right place so it doesn't try to load the pipelines next time.
@@ -562,7 +573,7 @@ void PipelineManagerVulkan::SaveCache(FILE *file, bool saveRawPipelineCache, Sha
 		fwrite(&size, sizeof(size), 1, file);
 		return;
 	}
-	NOTICE_LOG(G3D, "Saved Vulkan pipeline ID cache (%d pipelines).", (int)count);
+	NOTICE_LOG(G3D, "Saved Vulkan pipeline ID cache (%d unique pipelines/%d).", (int)keys.size(), (int)pipelines_.size());
 }
 
 bool PipelineManagerVulkan::LoadCache(FILE *file, bool loadRawPipelineCache, ShaderManagerVulkan *shaderManager, DrawEngineCommon *drawEngine, VkPipelineLayout layout, VkRenderPass renderPass) {

GPU/Vulkan/PipelineManagerVulkan.h

@@ -17,6 +17,7 @@
 
 #pragma once
 
+#include <cstring>
 #include "Common/Hashmaps.h"
 
 #include "GPU/Common/VertexDecoderCommon.h"
@@ -60,6 +61,11 @@ struct StoredVulkanPipelineKey {
 	FShaderID fShaderID;
 	uint32_t vtxFmtId;
 	bool useHWTransform;
+
+	// For std::set. Better zero-initialize the struct properly for this to work.
+	bool operator < (const StoredVulkanPipelineKey &other) const {
+		return memcmp(this, &other, sizeof(*this)) < 0;
+	}
 };
 
 enum PipelineFlags {

GPU/Vulkan/ShaderManagerVulkan.cpp

@@ -350,7 +350,7 @@ VulkanFragmentShader *ShaderManagerVulkan::GetFragmentShaderFromModule(VkShaderM
 // instantaneous.
 
 #define CACHE_HEADER_MAGIC 0xff51f420 
-#define CACHE_VERSION 5
+#define CACHE_VERSION 6
 struct VulkanCacheHeader {
 	uint32_t magic;
 	uint32_t version;