From 3754e64eace661e7130c95e3c6ce96220256589d Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Sun, 16 Feb 2025 13:53:46 +0100
Subject: [PATCH] [dxvk,d3d11] Fix draw buffer tracking for DrawAuto

Not like anybody uses this feature, but we need to both check for
hazards and make sure the SO counter actually gets tracked. Use
the existing draw buffer mechanism for this.
---
 src/d3d11/d3d11_context.cpp | 16 ++++++++++++++--
 src/dxvk/dxvk_context.cpp   | 16 +++++++++-------
 src/dxvk/dxvk_context.h     |  8 ++++----
 3 files changed, 27 insertions(+), 13 deletions(-)

diff --git a/src/d3d11/d3d11_context.cpp b/src/d3d11/d3d11_context.cpp
index bdbbf25a6d10..0868ab9edc7e 100644
--- a/src/d3d11/d3d11_context.cpp
+++ b/src/d3d11/d3d11_context.cpp
@@ -1009,10 +1009,22 @@ namespace dxvk {
     if (!ctrBuf.defined())
       return;
 
-    EmitCs([=] (DxvkContext* ctx) {
-      ctx->drawIndirectXfb(ctrBuf,
+    // We bind the SO counter as an indirect count buffer,
+    // so reset any tracking we may have been doing here.
+    m_state.id.reset();
+
+    EmitCs([=] (DxvkContext* ctx) mutable {
+      ctx->bindDrawBuffers(DxvkBufferSlice(),
+        Forwarder::move(ctrBuf));
+
+      ctx->drawIndirectXfb(0u,
         vtxBuf.buffer()->getXfbVertexStride(),
         vtxBuf.offset());
+
+      // Reset draw buffer right away so we don't
+      // keep the SO counter alive indefinitely
+      ctx->bindDrawBuffers(DxvkBufferSlice(),
+        DxvkBufferSlice());
     });
   }
 
diff --git a/src/dxvk/dxvk_context.cpp b/src/dxvk/dxvk_context.cpp
index e8adc0ede3b7..67d25e0c8d6c 100644
--- a/src/dxvk/dxvk_context.cpp
+++ b/src/dxvk/dxvk_context.cpp
@@ -1052,17 +1052,19 @@ namespace dxvk {
   
   
   void DxvkContext::drawIndirectXfb(
-    const DxvkBufferSlice&  counterBuffer,
+          VkDeviceSize      counterOffset,
           uint32_t          counterDivisor,
           uint32_t          counterBias) {
-    if (this->commitGraphicsState<false, false>()) {
-      auto physSlice = counterBuffer.getSliceHandle();
+    if (this->commitGraphicsState<false, true>()) {
+      auto physSlice = m_state.id.cntBuffer.getSliceHandle();
 
       m_cmd->cmdDrawIndirectVertexCount(1, 0,
-        physSlice.handle,
-        physSlice.offset,
-        counterBias,
-        counterDivisor);
+        physSlice.handle, physSlice.offset + counterOffset,
+        counterBias, counterDivisor);
+
+      // The count will generally be written from streamout
+      if (likely(m_state.id.cntBuffer.buffer()->hasGfxStores()))
+        accessDrawCountBuffer(counterOffset);
     }
   }
 
diff --git a/src/dxvk/dxvk_context.h b/src/dxvk/dxvk_context.h
index ace683ebff79..a3aba78d2890 100644
--- a/src/dxvk/dxvk_context.h
+++ b/src/dxvk/dxvk_context.h
@@ -832,14 +832,14 @@ namespace dxvk {
             uint32_t          stride);
     
     /**
-     * \brief Transform feddback draw call
-
-     * \param [in] counterBuffer Xfb counter buffer
+     * \brief Transform feedback draw call
+     *
+     * \param [in] counterOffset Draw count offset
      * \param [in] counterDivisor Vertex stride
      * \param [in] counterBias Counter bias
      */
     void drawIndirectXfb(
-      const DxvkBufferSlice&  counterBuffer,
+            VkDeviceSize      counterOffset,
             uint32_t          counterDivisor,
             uint32_t          counterBias);