Bypass pixel conversion when the output format is BGRA32

When the output format is BGRA32, we don't need any conversion at
all.  Skip the dummy copy.

diff --git a/com32/lib/sys/vesa/fmtpixel.c b/com32/lib/sys/vesa/fmtpixel.c
index 74c79ef..fc2732e 100644 (file)
--- a/com32/lib/sys/vesa/fmtpixel.c
+++ b/com32/lib/sys/vesa/fmtpixel.c
@@ -34,23 +34,21 @@
 #include <inttypes.h>
 #include "video.h"
 
-/* Format a pixel and return the advanced pointer.
-   THIS FUNCTION IS ALLOWED TO WRITE BEYOND THE END OF THE PIXEL. */
-
-static inline uint32_t *copy_dword(uint32_t *dst, const uint32_t *src,
-                                  size_t dword_count)
-{
-  asm volatile("cld; rep; movsl"
-              : "+D" (dst), "+S" (src), "+c" (dword_count));
-  return dst;                  /* Updated destination pointer */
-}
+/*
+ * Format a sequence of pixels.  The first argument is the line buffer;
+ * we can use it to write up to 4 bytes past the end of the last pixel.
+ * Return the place we should be copying from, this is usually the
+ * buffer address, but doesn't *have* to be.
+ */
 
-static void *format_pxf_bgra32(void *ptr, const uint32_t *p, size_t n)
+static const void *
+format_pxf_bgra32(void *ptr, const uint32_t *p, size_t n)
 {
-  return copy_dword(ptr, p, n);
+  return p;                    /* No conversion needed! */
 }
 
-static void *format_pxf_bgr24(void *ptr, const uint32_t *p, size_t n)
+static const void *
+format_pxf_bgr24(void *ptr, const uint32_t *p, size_t n)
 {
   char *q = ptr;
 
@@ -58,10 +56,11 @@ static void *format_pxf_bgr24(void *ptr, const uint32_t *p, size_t n)
     *(uint32_t *)q = *p++;
     q += 3;
   }
-  return q;
+  return ptr;
 }
 
-static void *format_pxf_le_rgb16_565(void *ptr, const uint32_t *p, size_t n)
+static const void *
+format_pxf_le_rgb16_565(void *ptr, const uint32_t *p, size_t n)
 {
   uint32_t bgra;
   uint16_t *q = ptr;
@@ -73,10 +72,11 @@ static void *format_pxf_le_rgb16_565(void *ptr, const uint32_t *p, size_t n)
       ((bgra >> (2+8-5)) & (0x3f << 5)) +
       ((bgra >> (3+16-11)) & (0x1f << 11));
   }
-  return q;
+  return ptr;
 }
 
-static void *format_pxf_le_rgb15_555(void *ptr, const uint32_t *p, size_t n)
+static const void *
+format_pxf_le_rgb15_555(void *ptr, const uint32_t *p, size_t n)
 {
   uint32_t bgra;
   uint16_t *q = ptr;
@@ -88,7 +88,7 @@ static void *format_pxf_le_rgb15_555(void *ptr, const uint32_t *p, size_t n)
       ((bgra >> (2+8-5)) & (0x1f << 5)) +
       ((bgra >> (3+16-10)) & (0x1f << 10));
   }
-  return q;
+  return ptr;
 }
 
 __vesacon_format_pixels_t __vesacon_format_pixels;

diff --git a/com32/lib/sys/vesa/screencpy.c b/com32/lib/sys/vesa/screencpy.c
index 837499e..ac9b24e 100644 (file)
--- a/com32/lib/sys/vesa/screencpy.c
+++ b/com32/lib/sys/vesa/screencpy.c
@@ -98,9 +98,8 @@ void __vesacon_copy_to_screen(size_t dst, const uint32_t *src, size_t npixels)
   char rowbuf[bytes+4];
   const char *s;
 
-  __vesacon_format_pixels(rowbuf, src, npixels);
+  s = (const char *)__vesacon_format_pixels(rowbuf, src, npixels);
 
-  s = rowbuf;
   while (bytes) {
     win_off = dst & omask;
     win_pos = dst & ~omask;

diff --git a/com32/lib/sys/vesa/video.h b/com32/lib/sys/vesa/video.h
index c5f2603..40537c1 100644 (file)
--- a/com32/lib/sys/vesa/video.h
+++ b/com32/lib/sys/vesa/video.h
@@ -60,7 +60,8 @@ enum vesa_pixel_format {
 };
 extern enum vesa_pixel_format __vesacon_pixel_format;
 extern unsigned int __vesacon_bytes_per_pixel;
-typedef void * (*__vesacon_format_pixels_t)(void *, const uint32_t *, size_t);
+typedef const void * (*__vesacon_format_pixels_t)(void *, const uint32_t *,
+                                                 size_t);
 extern __vesacon_format_pixels_t __vesacon_format_pixels;
 extern const __vesacon_format_pixels_t __vesacon_format_pixels_list[PXF_NONE];