RHI: ensure there is always a valid m_currentUpdates

downloadRHIBuffers() needs a valid QRhiResourceUpdateBatch

Fixes: QTBUG-121702
Change-Id: I22e97c028aa6b85b505b64b8f65f9a18e31ea2c9
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>
(cherry picked from commit c6e499dae2b943de4acf831be596eebc444d2315)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 6 insertions, 14 deletions

diff --git a/src/plugins/renderers/rhi/renderer/renderer.cpp b/src/plugins/renderers/rhi/renderer/renderer.cpp
index 824e741a5..3dffb3b64 100644
--- a/src/plugins/renderers/rhi/renderer/renderer.cpp
+++ b/src/plugins/renderers/rhi/renderer/renderer.cpp
@@ -2741,7 +2741,6 @@ bool Renderer::executeCommandsSubmission(const RHIPassInfo &passInfo)
 
     // All the RVs in the current passinfo target the same RenderTarget
     // A single beginPass should take place, unless Computes RVs are intermingled
-    QRhiResourceUpdateBatch *inPassUpdates = nullptr;
     static const bool supportsCompute = m_submissionContext->rhi()->isFeatureSupported(QRhi::Compute);
 
     // Per Pass Global States
@@ -2759,7 +2758,7 @@ bool Renderer::executeCommandsSubmission(const RHIPassInfo &passInfo)
             if (supportsCompute) {
                 if (!inCompute) {
                     cb->beginComputePass(m_submissionContext->m_currentUpdates);
-                    m_submissionContext->m_currentUpdates = nullptr;
+                    m_submissionContext->m_currentUpdates = m_submissionContext->rhi()->nextResourceUpdateBatch();
                     inCompute = true;
                 }
                 executeComputeRenderView(rv);
@@ -2781,7 +2780,7 @@ bool Renderer::executeCommandsSubmission(const RHIPassInfo &passInfo)
                     continue;
                 }
                 cb->beginPass(rhiRenderTarget, clearColor, clearDepthStencil, m_submissionContext->m_currentUpdates);
-                m_submissionContext->m_currentUpdates = nullptr;
+                m_submissionContext->m_currentUpdates = m_submissionContext->rhi()->nextResourceUpdateBatch();
                 inDraw = true;
             }
 
@@ -2830,8 +2829,7 @@ bool Renderer::executeCommandsSubmission(const RHIPassInfo &passInfo)
                         const QRhiColorAttachment *color0Att = desc.colorAttachmentAt(0);
                         readbackDesc.setTexture(color0Att->texture());
                     }
-                    inPassUpdates = m_submissionContext->rhi()->nextResourceUpdateBatch();
-                    inPassUpdates->readBackTexture(readbackDesc, readBackResult);
+                    m_submissionContext->m_currentUpdates->readBackTexture(readbackDesc, readBackResult);
                 } else {
                     qCWarning(Backend) << "Requested capture rectangle is outside framebuffer";
                 }
@@ -2843,17 +2841,11 @@ bool Renderer::executeCommandsSubmission(const RHIPassInfo &passInfo)
     }
 
     if (Q_LIKELY(inDraw))
-        cb->endPass(inPassUpdates);
+        cb->endPass(m_submissionContext->m_currentUpdates);
     else if (inCompute)
-        cb->endComputePass();
+        cb->endComputePass(m_submissionContext->m_currentUpdates);
 
-    if (!renderViews.empty()) {
-        Q_ASSERT(m_submissionContext->m_currentUpdates == nullptr); // ensures that we are not leaking a batch
-        m_submissionContext->m_currentUpdates = m_submissionContext->rhi()->nextResourceUpdateBatch();
-    }
-    else {
-        // Keep the m_submissionContext->m_currentUpdates
-    }
+    m_submissionContext->m_currentUpdates = m_submissionContext->rhi()->nextResourceUpdateBatch();
 
     return allCommandsIssued;
 }