From d64aafc0ede047d1eff93ee7aa77411c0d27aa21 Mon Sep 17 00:00:00 2001
From: Andrew Comminos <andrew@comminos.com>
Date: Mon, 5 Mar 2018 20:28:34 -0800
Subject: [PATCH 3/5] wined3d: Use ARB_multi_bind to speed up UBO updates.

More frequent UBO remaps as a result of the persistent buffer allocator
causes glBindBufferRange to be a bottleneck. Using ARB_multi_bind
massively reduces state change overhead.
---
 dlls/wined3d/directx.c    |  4 ++++
 dlls/wined3d/state.c      | 46 +++++++++++++++++++++++++++++++++++++++-------
 dlls/wined3d/wined3d_gl.h |  1 +
 3 files changed, 44 insertions(+), 7 deletions(-)

diff --git a/dlls/wined3d/directx.c b/dlls/wined3d/directx.c
index 46c6a59536..8789a501ec 100644
--- a/dlls/wined3d/directx.c
+++ b/dlls/wined3d/directx.c
@@ -149,6 +149,7 @@ static const struct wined3d_extension_map gl_extension_map[] =
     {"GL_ARB_internalformat_query2",        ARB_INTERNALFORMAT_QUERY2     },
     {"GL_ARB_map_buffer_alignment",         ARB_MAP_BUFFER_ALIGNMENT      },
     {"GL_ARB_map_buffer_range",             ARB_MAP_BUFFER_RANGE          },
+    {"GL_ARB_multi_bind",                   ARB_MULTI_BIND                },
     {"GL_ARB_multisample",                  ARB_MULTISAMPLE               },
     {"GL_ARB_multitexture",                 ARB_MULTITEXTURE              },
     {"GL_ARB_occlusion_query",              ARB_OCCLUSION_QUERY           },
@@ -2796,6 +2797,8 @@ static void load_gl_funcs(struct wined3d_gl_info *gl_info)
     /* GL_ARB_map_buffer_range */
     USE_GL_FUNC(glFlushMappedBufferRange)
     USE_GL_FUNC(glMapBufferRange)
+    /* GL_ARB_multi_bind */
+    USE_GL_FUNC(glBindBuffersRange)
     /* GL_ARB_multisample */
     USE_GL_FUNC(glSampleCoverageARB)
     /* GL_ARB_multitexture */
@@ -3973,6 +3976,7 @@ static BOOL wined3d_adapter_init_gl_caps(struct wined3d_adapter *adapter,
         {ARB_TEXTURE_VIEW,                 MAKEDWORD_VERSION(4, 3)},
 
         {ARB_CLEAR_TEXTURE,                MAKEDWORD_VERSION(4, 4)},
+        {ARB_MULTI_BIND,                   MAKEDWORD_VERSION(4, 4)},
 
         {ARB_CLIP_CONTROL,                 MAKEDWORD_VERSION(4, 5)},
         {ARB_CULL_DISTANCE,                MAKEDWORD_VERSION(4, 5)},
diff --git a/dlls/wined3d/state.c b/dlls/wined3d/state.c
index 6f7805b8bd..4d0718514f 100644
--- a/dlls/wined3d/state.c
+++ b/dlls/wined3d/state.c
@@ -5014,19 +5014,51 @@ static void state_cb(struct wined3d_context *context, const struct wined3d_state
         shader_type = WINED3D_SHADER_TYPE_COMPUTE;
 
     wined3d_gl_limits_get_uniform_block_range(&gl_info->limits, shader_type, &base, &count);
-    for (i = 0; i < count; ++i)
+
+    if (gl_info->supported[ARB_MULTI_BIND])
     {
-        buffer = state->cb[shader_type][i];
-        if (buffer)
+        GLuint buffer_objects[count];
+        GLsizeiptr buffer_offsets[count];
+        GLsizeiptr buffer_sizes[count];
+
+        for (i = 0; i < count; ++i)
         {
-            wined3d_buffer_get_memory(buffer, &bo_addr, buffer->locations);
-            GL_EXTCALL(glBindBufferRange(GL_UNIFORM_BUFFER, base + i, bo_addr.buffer_object, bo_addr.addr, bo_addr.length));
+            buffer = state->cb[shader_type][i];
+            if (buffer)
+            {
+                wined3d_buffer_get_memory(buffer, &bo_addr, buffer->locations);
+                buffer_objects[i] = bo_addr.buffer_object;
+                buffer_offsets[i] = bo_addr.addr;
+                buffer_sizes[i] = bo_addr.length;
+            }
+            else
+            {
+                buffer_objects[i] = buffer_offsets[i] = 0;
+                // The ARB_multi_bind spec states that an error may be thrown if
+                // `size` is less than or equal to zero, Thus, we specify a size for
+                // unused buffers anyway.
+                buffer_sizes[i] = 1;
+            }
         }
-        else
+        GL_EXTCALL(glBindBuffersRange(GL_UNIFORM_BUFFER, base, count, buffer_objects, buffer_offsets, buffer_sizes));
+    }
+    else
+    {
+        for (i = 0; i < count; ++i)
         {
-            GL_EXTCALL(glBindBufferBase(GL_UNIFORM_BUFFER, base + i, 0));
+            buffer = state->cb[shader_type][i];
+            if (buffer)
+            {
+                wined3d_buffer_get_memory(buffer, &bo_addr, buffer->locations);
+                GL_EXTCALL(glBindBufferRange(GL_UNIFORM_BUFFER, base + i, bo_addr.buffer_object, bo_addr.addr, bo_addr.length));
+            }
+            else
+            {
+                GL_EXTCALL(glBindBufferBase(GL_UNIFORM_BUFFER, base + i, 0));
+            }
         }
     }
+
     checkGLcall("bind constant buffers");
 }
 
diff --git a/dlls/wined3d/wined3d_gl.h b/dlls/wined3d/wined3d_gl.h
index 7626864ef2..25c3301c94 100644
--- a/dlls/wined3d/wined3d_gl.h
+++ b/dlls/wined3d/wined3d_gl.h
@@ -82,6 +82,7 @@ enum wined3d_gl_extension
     ARB_INTERNALFORMAT_QUERY2,
     ARB_MAP_BUFFER_ALIGNMENT,
     ARB_MAP_BUFFER_RANGE,
+    ARB_MULTI_BIND,
     ARB_MULTISAMPLE,
     ARB_MULTITEXTURE,
     ARB_OCCLUSION_QUERY,
-- 
2.16.2