From 7fd87c704a7be0ed4b9929979f43f0e5874eb857 Mon Sep 17 00:00:00 2001
From: Jesse Natalie <jenatali@microsoft.com>
Date: Thu, 10 Sep 2020 16:25:58 -0700
Subject: [PATCH] Use power-of-two alignment values for allocating pixel data
 (#827)

---
 test_common/harness/imageHelpers.cpp | 35 +++++++++++++++++++++-------
 test_common/harness/imageHelpers.h   | 10 ++++----
 2 files changed, 32 insertions(+), 13 deletions(-)

diff --git a/test_common/harness/imageHelpers.cpp b/test_common/harness/imageHelpers.cpp
index d5cdc7a1..807f4338 100644
--- a/test_common/harness/imageHelpers.cpp
+++ b/test_common/harness/imageHelpers.cpp
@@ -72,12 +72,12 @@ sRGBunmap(float fc)
 }
 
 
-size_t get_format_type_size( const cl_image_format *format )
+uint32_t get_format_type_size(const cl_image_format *format)
 {
     return get_channel_data_type_size( format->image_channel_data_type );
 }
 
-size_t get_channel_data_type_size( cl_channel_type channelType )
+uint32_t get_channel_data_type_size(cl_channel_type channelType)
 {
     switch( channelType )
     {
@@ -129,12 +129,12 @@ size_t get_channel_data_type_size( cl_channel_type channelType )
     }
 }
 
-size_t get_format_channel_count( const cl_image_format *format )
+uint32_t get_format_channel_count(const cl_image_format *format)
 {
     return get_channel_order_channel_count( format->image_channel_order );
 }
 
-size_t get_channel_order_channel_count( cl_channel_order order )
+uint32_t get_channel_order_channel_count(cl_channel_order order)
 {
     switch( order )
     {
@@ -281,7 +281,7 @@ int is_format_signed( const cl_image_format *format )
     }
 }
 
-size_t get_pixel_size( cl_image_format *format )
+uint32_t get_pixel_size(cl_image_format *format)
 {
   switch( format->image_channel_data_type )
   {
@@ -333,6 +333,23 @@ size_t get_pixel_size( cl_image_format *format )
   }
 }
 
+uint32_t next_power_of_two(uint32_t v)
+{
+    v--;
+    v |= v >> 1;
+    v |= v >> 2;
+    v |= v >> 4;
+    v |= v >> 8;
+    v |= v >> 16;
+    v++;
+    return v;
+}
+
+uint32_t get_pixel_alignment(cl_image_format *format)
+{
+    return next_power_of_two(get_pixel_size(format));
+}
+
 int get_8_bit_image_format( cl_context context, cl_mem_object_type objType, cl_mem_flags flags, size_t channelCount, cl_image_format *outFormat )
 {
     cl_image_format formatList[ 128 ];
@@ -1019,7 +1036,8 @@ char * generate_random_image_data( image_descriptor *imageInfo, BufferOwningPtr<
     }
 #else
     P.reset( NULL ); // Free already allocated memory first, then try to allocate new block.
-    char *data = (char *)align_malloc(allocSize, get_pixel_size(imageInfo->format));
+    char *data =
+        (char *)align_malloc(allocSize, get_pixel_alignment(imageInfo->format));
     P.reset(data,NULL,0,allocSize, true);
 #endif
 
@@ -2942,8 +2960,9 @@ char *create_random_image_data( ExplicitType dataType, image_descriptor *imageIn
       P.reset(data);
     }
 #else
-    char *data = (char *)align_malloc(allocSize, get_pixel_size(imageInfo->format));
-    P.reset(data,NULL,0,allocSize,true);
+  char *data =
+      (char *)align_malloc(allocSize, get_pixel_alignment(imageInfo->format));
+  P.reset(data, NULL, 0, allocSize, true);
 #endif
 
     if (data == NULL) {
diff --git a/test_common/harness/imageHelpers.h b/test_common/harness/imageHelpers.h
index a50e85f1..a3feb72b 100644
--- a/test_common/harness/imageHelpers.h
+++ b/test_common/harness/imageHelpers.h
@@ -83,14 +83,14 @@ extern void build_required_image_formats(cl_mem_flags flags,
                                          cl_device_id device,
                                          std::vector<cl_image_format>& formatsToSupport);
 
-extern size_t get_format_type_size( const cl_image_format *format );
-extern size_t get_channel_data_type_size( cl_channel_type channelType );
-extern size_t get_format_channel_count( const cl_image_format *format );
-extern size_t get_channel_order_channel_count( cl_channel_order order );
+extern uint32_t get_format_type_size(const cl_image_format *format);
+extern uint32_t get_channel_data_type_size(cl_channel_type channelType);
+extern uint32_t get_format_channel_count(const cl_image_format *format);
+extern uint32_t get_channel_order_channel_count(cl_channel_order order);
 cl_channel_type  get_channel_type_from_name( const char *name );
 cl_channel_order  get_channel_order_from_name( const char *name );
 extern int    is_format_signed( const cl_image_format *format );
-extern size_t get_pixel_size( cl_image_format *format );
+extern uint32_t get_pixel_size(cl_image_format *format);
 
 /* Helper to get any ol image format as long as it is 8-bits-per-channel */
 extern int get_8_bit_image_format( cl_context context, cl_mem_object_type objType, cl_mem_flags flags, size_t channelCount, cl_image_format *outFormat );