From 6d8b811414c73df7f75cc192e3b1f1d777615bdc Mon Sep 17 00:00:00 2001
From: Siarhei Siamashka <siarhei.siamashka@nokia.com>
Date: Thu, 22 Oct 2009 05:45:47 +0300
Subject: [PATCH 2/4] Support of overlapping src/dst for pixman_blt_mmx

---
 pixman/pixman-mmx.c |   55 +++++++++++++++++++++++++++++---------------------
 1 files changed, 32 insertions(+), 23 deletions(-)

diff --git a/pixman/pixman-mmx.c b/pixman/pixman-mmx.c
index 0272347..5bcbd0e 100644
--- a/pixman/pixman-mmx.c
+++ b/pixman/pixman-mmx.c
@@ -2996,34 +2996,43 @@ pixman_blt_mmx (uint32_t *src_bits,
 {
     uint8_t *   src_bytes;
     uint8_t *   dst_bytes;
-    int byte_width;
+    int         bpp;
 
-    if (src_bpp != dst_bpp)
+    if (src_bpp != dst_bpp || src_bpp & 7)
 	return FALSE;
 
-    if (src_bpp == 16)
-    {
-	src_stride = src_stride * (int) sizeof (uint32_t) / 2;
-	dst_stride = dst_stride * (int) sizeof (uint32_t) / 2;
-	src_bytes = (uint8_t *)(((uint16_t *)src_bits) + src_stride * (src_y) + (src_x));
-	dst_bytes = (uint8_t *)(((uint16_t *)dst_bits) + dst_stride * (dst_y) + (dst_x));
-	byte_width = 2 * width;
-	src_stride *= 2;
-	dst_stride *= 2;
-    }
-    else if (src_bpp == 32)
+    bpp = src_bpp >> 3;
+    width *= bpp;
+    src_stride *= 4;
+    dst_stride *= 4;
+    src_bytes = (uint8_t *)src_bits + src_y * src_stride + src_x * bpp;
+    dst_bytes = (uint8_t *)dst_bits + dst_y * dst_stride + dst_x * bpp;
+
+    if (src_bpp != 16 && src_bpp != 32)
     {
-	src_stride = src_stride * (int) sizeof (uint32_t) / 4;
-	dst_stride = dst_stride * (int) sizeof (uint32_t) / 4;
-	src_bytes = (uint8_t *)(((uint32_t *)src_bits) + src_stride * (src_y) + (src_x));
-	dst_bytes = (uint8_t *)(((uint32_t *)dst_bits) + dst_stride * (dst_y) + (dst_x));
-	byte_width = 4 * width;
-	src_stride *= 4;
-	dst_stride *= 4;
+	pixman_blt_helper (src_bytes, dst_bytes, src_stride, dst_stride,
+	                   width, height);
+	return TRUE;
     }
-    else
+
+    if (src_bytes < dst_bytes && src_bytes + src_stride * height > dst_bytes)
     {
-	return FALSE;
+	src_bytes += src_stride * height - src_stride;
+	dst_bytes += dst_stride * height - dst_stride;
+	dst_stride = -dst_stride;
+	src_stride = -src_stride;
+
+	if (src_bytes + width > dst_bytes)
+	{
+	    /* TODO: reverse scanline copy using MMX */
+	    while (--height >= 0)
+	    {
+		memmove (dst_bytes, src_bytes, width);
+		dst_bytes += dst_stride;
+		src_bytes += src_stride;
+	    }
+	    return TRUE;
+	}
     }
 
     while (height--)
@@ -3033,7 +3042,7 @@ pixman_blt_mmx (uint32_t *src_bits,
 	uint8_t *d = dst_bytes;
 	src_bytes += src_stride;
 	dst_bytes += dst_stride;
-	w = byte_width;
+	w = width;
 
 	while (w >= 2 && ((unsigned long)d & 3))
 	{
-- 
1.6.6.1

