From caffd8f81da088ec51bb9517144eb326a34d2ccf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pablo=20Delgado=20Kr=C3=A4mer?= <private@pablode.com>
Date: Tue, 30 Jul 2024 19:05:48 +0200
Subject: [PATCH] gb/cgpu/gi: add data alignment helper function

---
 src/cgpu/impl/Cgpu.cpp | 14 +++++---------
 src/gb/CMakeLists.txt  |  1 +
 src/gb/gtl/gb/Data.h   | 32 ++++++++++++++++++++++++++++++++
 src/gi/impl/Gi.cpp     |  3 ++-
 4 files changed, 40 insertions(+), 10 deletions(-)
 create mode 100644 src/gb/gtl/gb/Data.h

diff --git a/src/cgpu/impl/Cgpu.cpp b/src/cgpu/impl/Cgpu.cpp
index 2044afc9..95efab0e 100644
--- a/src/cgpu/impl/Cgpu.cpp
+++ b/src/cgpu/impl/Cgpu.cpp
@@ -27,6 +27,7 @@
 
 #include <volk.h>
 
+#include <gtl/gb/Data.h>
 #include <gtl/gb/Fmt.h>
 #include <gtl/gb/Log.h>
 
@@ -1794,11 +1795,6 @@ namespace gtl
     return true;
   }
 
-  static uint32_t cgpuAlignSize(uint32_t size, uint32_t alignment)
-  {
-      return (size + (alignment - 1)) & ~(alignment - 1);
-  }
-
   static bool cgpuCreateRtPipelineSbt(CgpuIDevice* idevice,
                                       CgpuIPipeline* ipipeline,
                                       uint32_t groupCount,
@@ -1806,14 +1802,14 @@ namespace gtl
                                       uint32_t hitGroupCount)
   {
     uint32_t handleSize = idevice->properties.shaderGroupHandleSize;
-    uint32_t alignedHandleSize = cgpuAlignSize(handleSize, idevice->properties.shaderGroupHandleAlignment);
+    uint32_t alignedHandleSize = gbAlignUpwards(handleSize, idevice->properties.shaderGroupHandleAlignment);
 
-    ipipeline->sbtRgen.stride = cgpuAlignSize(alignedHandleSize, idevice->properties.shaderGroupBaseAlignment);
+    ipipeline->sbtRgen.stride = gbAlignUpwards(alignedHandleSize, idevice->properties.shaderGroupBaseAlignment);
     ipipeline->sbtRgen.size = ipipeline->sbtRgen.stride; // Special raygen condition: size must be equal to stride
     ipipeline->sbtMiss.stride = alignedHandleSize;
-    ipipeline->sbtMiss.size = cgpuAlignSize(missShaderCount * alignedHandleSize, idevice->properties.shaderGroupBaseAlignment);
+    ipipeline->sbtMiss.size = gbAlignUpwards(missShaderCount * alignedHandleSize, idevice->properties.shaderGroupBaseAlignment);
     ipipeline->sbtHit.stride = alignedHandleSize;
-    ipipeline->sbtHit.size = cgpuAlignSize(hitGroupCount * alignedHandleSize, idevice->properties.shaderGroupBaseAlignment);
+    ipipeline->sbtHit.size = gbAlignUpwards(hitGroupCount * alignedHandleSize, idevice->properties.shaderGroupBaseAlignment);
 
     uint32_t firstGroup = 0;
     uint32_t dataSize = handleSize * groupCount;
diff --git a/src/gb/CMakeLists.txt b/src/gb/CMakeLists.txt
index d91163a9..c535689a 100644
--- a/src/gb/CMakeLists.txt
+++ b/src/gb/CMakeLists.txt
@@ -1,5 +1,6 @@
 add_library(
   gb STATIC
+  gtl/gb/Data.h
   gtl/gb/Fmt.h
   gtl/gb/HandleStore.h
   gtl/gb/LinearDataStore.h
diff --git a/src/gb/gtl/gb/Data.h b/src/gb/gtl/gb/Data.h
new file mode 100644
index 00000000..a9182605
--- /dev/null
+++ b/src/gb/gtl/gb/Data.h
@@ -0,0 +1,32 @@
+//
+// Copyright (C) 2024 Pablo Delgado Krämer
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+//
+
+#pragma once
+
+namespace gtl
+{
+  template<std::integral T>
+  T gbAlignUpwards(T value, T alignment)
+  {
+    if (alignment == T(0))
+    {
+      return value;
+    }
+
+    return (value + alignment - T(1)) / alignment * alignment;
+  }
+}
diff --git a/src/gi/impl/Gi.cpp b/src/gi/impl/Gi.cpp
index 9d3f4874..cc0a1941 100644
--- a/src/gi/impl/Gi.cpp
+++ b/src/gi/impl/Gi.cpp
@@ -53,6 +53,7 @@
 #include <gtl/mc/Frontend.h>
 #include <gtl/mc/Runtime.h>
 #include <gtl/gb/Log.h>
+#include <gtl/gb/Data.h>
 
 #include <MaterialXCore/Document.h>
 
@@ -505,7 +506,7 @@ namespace gtl
       return *totalSize;
     }
 
-    const uint64_t offset = ((*totalSize) + alignment - 1) / alignment * alignment;
+    const uint64_t offset = gbAlignUpwards(*totalSize, alignment);
 
     (*totalSize) = offset + bufferSize;