rhi: d3d: Fix resource binding mismatch with multiple passes

The resetShaderResources() done when starting a render or compute pass
purges all vertex, index, SRV, and UAV bindings. This will be optimized
at a later point, but until then the command buffer's state should be
updated accordingly, otherwise certain use cases end up with incorrect
rendering results due to not binding vertex/index/shader resources
as appropriate.

This fixes the shadowmap example on d3d.

Change-Id: I4d07929b8664b64bc608c6c8df474b0ee7c2ddbb
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

src/gui/rhi/qrhid3d11.cpp

@@ -1480,6 +1480,8 @@ void QRhiD3D11::beginPass(QRhiCommandBuffer *cb,
 
     cbD->recordingPass = QD3D11CommandBuffer::RenderPass;
     cbD->currentTarget = rt;
+
+    cbD->resetCachedShaderResourceState();
 }
 
 void QRhiD3D11::endPass(QRhiCommandBuffer *cb, QRhiResourceUpdateBatch *resourceUpdates)
@@ -1556,6 +1558,8 @@ void QRhiD3D11::beginComputePass(QRhiCommandBuffer *cb, QRhiResourceUpdateBatch
     cbD->commands.append(cmd);
 
     cbD->recordingPass = QD3D11CommandBuffer::ComputePass;
+
+    cbD->resetCachedShaderResourceState();
 }
 
 void QRhiD3D11::endComputePass(QRhiCommandBuffer *cb, QRhiResourceUpdateBatch *resourceUpdates)

src/gui/rhi/qrhid3d11_p_p.h

@@ -482,6 +482,9 @@ struct QD3D11CommandBuffer : public QRhiCommandBuffer
         currentGraphicsPipeline = nullptr;
         currentComputePipeline = nullptr;
         currentPipelineGeneration = 0;
+        resetCachedShaderResourceState();
+    }
+    void resetCachedShaderResourceState() {
         currentGraphicsSrb = nullptr;
         currentComputeSrb = nullptr;
         currentSrbGeneration = 0;