[PATCH 1/3] gdi32: Eliminate a masking operation by generating a larger colour table.

[Huw Davies]

This helps significantly for large rectangles.

This is only done for the 32-bpp case as typically the lower bit
depths would more likely be used to draw small icons and the like,
where the extra fixed cost of this optimization will potentially
outweigh the savings.

Signed-off-by: Huw Davies <huw at codeweavers.com>
---
 dlls/gdi32/dibdrv/primitives.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/dlls/gdi32/dibdrv/primitives.c b/dlls/gdi32/dibdrv/primitives.c
index e75792c..d512af2 100644
--- a/dlls/gdi32/dibdrv/primitives.c
+++ b/dlls/gdi32/dibdrv/primitives.c
@@ -5264,7 +5264,7 @@ static BOOL gradient_rect_null( const dib_info *dib, const RECT *rc, const TRIVE
 static void mask_rect_32( const dib_info *dst, const RECT *rc,
                           const dib_info *src, const POINT *origin, int rop2 )
 {
-    DWORD *dst_start = get_pixel_ptr_32(dst, rc->left, rc->top), dst_colors[2];
+    DWORD *dst_start = get_pixel_ptr_32(dst, rc->left, rc->top), dst_colors[256];
     DWORD src_val, bit_val, i, full, pos;
     struct rop_codes codes;
     int x, y;
@@ -5274,15 +5274,19 @@ static void mask_rect_32( const dib_info *dst, const RECT *rc,
     get_rop_codes( rop2, &codes );
 
     if (dst->funcs == &funcs_8888)
-        for (i = 0; i < sizeof(dst_colors) / sizeof(dst_colors[0]); i++)
+        for (i = 0; i < 2; i++)
             dst_colors[i] = color_table[i].rgbRed << 16 | color_table[i].rgbGreen << 8 |
                 color_table[i].rgbBlue;
     else
-        for (i = 0; i < sizeof(dst_colors) / sizeof(dst_colors[0]); i++)
+        for (i = 0; i < 2; i++)
             dst_colors[i] = put_field(color_table[i].rgbRed,   dst->red_shift,   dst->red_len) |
                             put_field(color_table[i].rgbGreen, dst->green_shift, dst->green_len) |
                             put_field(color_table[i].rgbBlue,  dst->blue_shift,  dst->blue_len);
 
+    /* Creating a BYTE-sized table so we don't need to mask the lsb of bit_val */
+    for (i = 2; i < sizeof(dst_colors) / sizeof(dst_colors[0]); i++)
+        dst_colors[i] = dst_colors[i & 1];
+
     for (y = rc->top; y < rc->bottom; y++)
     {
         pos = origin->x & 7;
@@ -5298,21 +5302,21 @@ static void mask_rect_32( const dib_info *dst, const RECT *rc,
         {
             src_val = src_start[pos / 8];
 
-            bit_val = (src_val >> 7) & 1;
+            bit_val = src_val >> 7;
             do_rop_codes_32( dst_start + x++, dst_colors[bit_val], &codes );
-            bit_val = (src_val >> 6) & 1;
+            bit_val = src_val >> 6;
             do_rop_codes_32( dst_start + x++, dst_colors[bit_val], &codes );
-            bit_val = (src_val >> 5) & 1;
+            bit_val = src_val >> 5;
             do_rop_codes_32( dst_start + x++, dst_colors[bit_val], &codes );
-            bit_val = (src_val >> 4) & 1;
+            bit_val = src_val >> 4;
             do_rop_codes_32( dst_start + x++, dst_colors[bit_val], &codes );
-            bit_val = (src_val >> 3) & 1;
+            bit_val = src_val >> 3;
             do_rop_codes_32( dst_start + x++, dst_colors[bit_val], &codes );
-            bit_val = (src_val >> 2) & 1;
+            bit_val = src_val >> 2;
             do_rop_codes_32( dst_start + x++, dst_colors[bit_val], &codes );
-            bit_val = (src_val >> 1) & 1;
+            bit_val = src_val >> 1;
             do_rop_codes_32( dst_start + x++, dst_colors[bit_val], &codes );
-            bit_val = src_val & 1;
+            bit_val = src_val;
             do_rop_codes_32( dst_start + x++, dst_colors[bit_val], &codes );
         }
 
-- 
2.7.4