Merge pull request #1020 from billhollings/master

Fix Metal validation error when occlusion query and renderpass are in separate Vulkan command buffers.

Docs/Whats_New.md

@@ -40,6 +40,8 @@ Released TBD
   within each descriptor set.
 - `vkCmdCopyImage` on macOS flush non-coherent image memory before copy operation.
 - Re-add support for bitcode generation on *iOS* and *tvOS*.
+- Fix Metal validation error when occlusion query and renderpass are in separate 
+  Vulkan command buffers.
 
 
 

MoltenVK/MoltenVK/Commands/MVKCmdRenderPass.mm

@@ -118,6 +118,7 @@ VkResult MVKCmdExecuteCommands<N>::setContent(MVKCommandBuffer* cmdBuff,
 	for (uint32_t cbIdx = 0; cbIdx < commandBuffersCount; cbIdx++) {
 		_secondaryCommandBuffers.push_back(MVKCommandBuffer::getMVKCommandBuffer(pCommandBuffers[cbIdx]));
 	}
+	cmdBuff->recordExecuteCommands(_secondaryCommandBuffers.contents());
 
 	return VK_SUCCESS;
 }

MoltenVK/MoltenVK/Commands/MVKCommandBuffer.h

@@ -97,6 +97,8 @@ public:
      */
     id<MTLBuffer> _initialVisibilityResultMTLBuffer;
 
+	/** Called when a MVKCmdExecuteCommands is added to this command buffer. */
+	void recordExecuteCommands(const MVKArrayRef<MVKCommandBuffer*> secondaryCommandBuffers);
 
 #pragma mark Tessellation constituent command management
 

MoltenVK/MoltenVK/Commands/MVKCommandBuffer.mm

@@ -195,6 +195,19 @@ MVKCommandBuffer::~MVKCommandBuffer() {
 	reset(0);
 }
 
+// If the initial visibility result buffer has not been set, promote the first visibility result buffer
+// found among any of the secondary command buffers, to support the case where a render pass is started in
+// the primary command buffer but the visibility query is started inside one of the secondary command buffers.
+void MVKCommandBuffer::recordExecuteCommands(const MVKArrayRef<MVKCommandBuffer*> secondaryCommandBuffers) {
+	if (_initialVisibilityResultMTLBuffer == nil) {
+		for (MVKCommandBuffer* cmdBuff : secondaryCommandBuffers) {
+			if (cmdBuff->_initialVisibilityResultMTLBuffer) {
+				_initialVisibilityResultMTLBuffer = cmdBuff->_initialVisibilityResultMTLBuffer;
+				break;
+			}
+		}
+	}
+}
 
 #pragma mark -
 #pragma mark Tessellation constituent command management