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For writing and reading single pixels, avoid some pessimizations for

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depths > 8.  Add some smaller optimizations for these depths.  Use a
more generic method for all depths >= 8, although this gives tiny
pessimizations for these depths.

For clearing the whole frame buffer, avoid the same pessimizations
for depths > 8.  Add some larger optimizations for these depths.  Use
an even more generic method for all depths >= 8 to give the optimizations
for depths > 8 and a tiny pessimization for depth 8.

The main pessimization was that old versions of bcopy() copy 1 byte at a
time for all trailing bytes.  (i386 still does this.  amd64 now pessimizzes
large sizes instead of small ones if the CPU supports ERMS.  dev/fb gets
this wrong by mostly not using the bcopy() family or the technically correct
bus space functions but by mostly copying 2 bytes at a time using an
unoptimized loop without even volatile declarations to prevent the compiler
rewriting it.)

The sizes here are 1, 2, 3 or 4 bytes, so depths 9-16 were up to twice as
slow as necessary and depths 17-24 were up to 3 times slower than necessary.
Fix this (except depths 17-24 are still up to 2 times slower than necessary)
by using (builtin) memcpy() instead of bcopy() and reorganizing so that the
complier can see the small constant sizes.  Reduce special cases while
reorganizing although this is slightly slower than adding special cases.
The compiler inlining (and even -O2 vs -O0) makes little difference compared
with reducing the number of accesses except on modern hardware it gives a
small improvement.

Clearing was also pessimized mainly by the extra accesses.  Fix it quite
differently by creating a MEMBUF containing 1 line (in fast memory using
a slow method) and copying this.  This is only slightly slower than reducing
everything to efficient memset()s and bcopy()s, but simpler, especially
for the segmented case.  This works for planar modes too, but don't use it
then since the old method was actually optimal for planar modes (it works
by moving the slow i/o instructions out of inner loops), while for direct
modes the slow instructions were all in the invisible inner loop in bcopy().

Use htole32() and le32toh() and some type puns instead of unoptimized
functions for converting colors.  This optimization is mostly in the noise.
libvgl is only supported on x86, so it could hard-code the assumption that
the byte order is le32, but the old conversion functions didn't hard-code
this.
This commit is contained in:
Bruce Evans 2019-04-14 13:37:50 +00:00
parent e6481fd4c4
commit 5cf92d7aed
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=346215
1 changed files with 66 additions and 146 deletions
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212
lib/libvgl/simple.c
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@ -33,6 +33,7 @@ __FBSDID("$FreeBSD$");
#include <signal.h>
#include <sys/fbio.h>
#include <sys/endian.h>
#include "vgl.h"
static byte VGLSavePaletteRed[256];
@ -44,96 +45,44 @@ static byte VGLSavePaletteBlue[256];
#define min(x, y) (((x) < (y)) ? (x) : (y))
#define max(x, y) (((x) > (y)) ? (x) : (y))
static void
color2mem(u_long color, byte *b, int len)
{
switch (len) {
case 4:
b[3] = (color >> 24) & 0xff;
/* fallthrough */
case 3:
b[2] = (color >> 16) & 0xff;
/* fallthrough */
case 2:
b[1] = (color >> 8) & 0xff;
/* fallthrough */
case 1:
default:
b[0] = color & 0xff;
break;
}
return;
}
static u_long
mem2color(byte *b, int len)
{
u_long color = 0;
switch (len) {
case 4:
color |= (b[3] & 0xff) << 24;
/* fallthrough */
case 3:
color |= (b[2] & 0xff) << 16;
/* fallthrough */
case 2:
color |= (b[1] & 0xff) << 8;
/* fallthrough */
case 1:
default:
color |= (b[0] & 0xff);
break;
}
return color;
}
void
VGLSetXY(VGLBitmap *object, int x, int y, u_long color)
{
int offset;
byte b[4];
VGLCheckSwitch();
if (x>=0 && x<object->VXsize && y>=0 && y<object->VYsize) {
if (object->Type == MEMBUF ||
!VGLMouseFreeze(x, y, 1, 1, 0x80000000 | color)) {
offset = (y * object->VXsize + x) * object->PixelBytes;
switch (object->Type) {
case MEMBUF:
switch (object->PixelBytes) {
case 2:
goto vidbuf16;
case 3:
goto vidbuf24;
case 4:
goto vidbuf32;
}
/* fallthrough */
case VIDBUF8:
object->Bitmap[y*object->VXsize+x]=((byte)color);
break;
case VIDBUF8S:
object->Bitmap[VGLSetSegment(y*object->VXsize+x)]=((byte)color);
break;
case VIDBUF16:
vidbuf16:
case VIDBUF24:
vidbuf24:
case VIDBUF32:
vidbuf32:
color2mem(color, b, object->PixelBytes);
bcopy(b, &object->Bitmap[(y*object->VXsize+x) * object->PixelBytes],
object->PixelBytes);
break;
case VIDBUF16S:
case VIDBUF24S:
case VIDBUF32S:
color2mem(color, b, object->PixelBytes);
offset = VGLSetSegment((y*object->VXsize+x) * object->PixelBytes);
bcopy(b, &object->Bitmap[offset], object->PixelBytes);
break;
offset = VGLSetSegment(offset);
/* FALLTHROUGH */
case MEMBUF:
case VIDBUF8:
case VIDBUF16:
case VIDBUF24:
case VIDBUF32:
color = htole32(color);
switch (object->PixelBytes) {
case 1:
memcpy(&object->Bitmap[offset], &color, 1);
break;
case 2:
memcpy(&object->Bitmap[offset], &color, 2);
break;
case 3:
memcpy(&object->Bitmap[offset], &color, 3);
break;
case 4:
memcpy(&object->Bitmap[offset], &color, 4);
break;
}
break;
case VIDBUF8X:
outb(0x3c4, 0x02);
outb(0x3c5, 0x01 << (x&0x3));
@ -161,42 +110,38 @@ static u_long
__VGLGetXY(VGLBitmap *object, int x, int y)
{
int offset;
byte b[4];
int i;
u_long color;
byte mask;
offset = (y * object->VXsize + x) * object->PixelBytes;
switch (object->Type) {
case MEMBUF:
switch (object->PixelBytes) {
case 2:
goto vidbuf16;
case 3:
goto vidbuf24;
case 4:
goto vidbuf32;
}
/* fallthrough */
case VIDBUF8:
return object->Bitmap[((y*object->VXsize)+x)];
case VIDBUF8S:
return object->Bitmap[VGLSetSegment(y*object->VXsize+x)];
case VIDBUF16:
vidbuf16:
case VIDBUF24:
vidbuf24:
case VIDBUF32:
vidbuf32:
bcopy(&object->Bitmap[(y*object->VXsize+x) * object->PixelBytes],
b, object->PixelBytes);
return (mem2color(b, object->PixelBytes));
case VIDBUF16S:
case VIDBUF24S:
case VIDBUF32S:
offset = VGLSetSegment((y*object->VXsize+x) * object->PixelBytes);
bcopy(&object->Bitmap[offset], b, object->PixelBytes);
return (mem2color(b, object->PixelBytes));
offset = VGLSetSegment(offset);
/* FALLTHROUGH */
case MEMBUF:
case VIDBUF8:
case VIDBUF16:
case VIDBUF24:
case VIDBUF32:
switch (object->PixelBytes) {
case 1:
memcpy(&color, &object->Bitmap[offset], 1);
return le32toh(color) & 0xff;
case 2:
memcpy(&color, &object->Bitmap[offset], 2);
return le32toh(color) & 0xffff;
case 3:
memcpy(&color, &object->Bitmap[offset], 3);
return le32toh(color) & 0xffffff;
case 4:
memcpy(&color, &object->Bitmap[offset], 4);
return le32toh(color);
}
break;
case VIDBUF8X:
outb(0x3ce, 0x04); outb(0x3cf, x & 0x3);
return object->Bitmap[(unsigned)(VGLAdpInfo.va_line_width*y)+(x/4)];
@ -539,63 +484,38 @@ VGLFilledEllipse(VGLBitmap *object, int xc, int yc, int a, int b, u_long color)
void
VGLClear(VGLBitmap *object, u_long color)
{
VGLBitmap src;
int offset;
int len;
int i, total = 0;
byte b[4];
int i;
VGLCheckSwitch();
if (object->Type != MEMBUF)
VGLMouseFreeze(0, 0, object->Xsize, object->Ysize, color);
switch (object->Type) {
case MEMBUF:
switch (object->PixelBytes) {
case 2:
goto vidbuf16;
case 3:
goto vidbuf24;
case 4:
goto vidbuf32;
}
/* fallthrough */
case VIDBUF8:
memset(object->Bitmap, (byte)color, object->VXsize*object->VYsize);
break;
case VIDBUF8S:
for (offset = 0; offset < object->VXsize*object->VYsize; ) {
VGLSetSegment(offset);
len = min(object->VXsize*object->VYsize - offset,
VGLAdpInfo.va_window_size);
memset(object->Bitmap, (byte)color, len);
offset += len;
}
break;
case VIDBUF16:
vidbuf16:
case VIDBUF24:
vidbuf24:
case VIDBUF32:
vidbuf32:
color2mem(color, b, object->PixelBytes);
total = object->VXsize*object->VYsize*object->PixelBytes;
for (i = 0; i < total; i += object->PixelBytes)
bcopy(b, object->Bitmap + i, object->PixelBytes);
break;
case VIDBUF16S:
case VIDBUF24:
case VIDBUF24S:
case VIDBUF32:
case VIDBUF32S:
color2mem(color, b, object->PixelBytes);
total = object->VXsize*object->VYsize*object->PixelBytes;
for (offset = 0; offset < total; ) {
VGLSetSegment(offset);
len = min(total - offset, VGLAdpInfo.va_window_size);
for (i = 0; i < len; i += object->PixelBytes)
bcopy(b, object->Bitmap + (offset + i) % VGLAdpInfo.va_window_size,
object->PixelBytes);
offset += len;
}
src.Type = MEMBUF;
src.Xsize = object->Xsize;
src.VXsize = object->VXsize;
src.Ysize = 1;
src.VYsize = 1;
src.Xorigin = 0;
src.Yorigin = 0;
src.Bitmap = alloca(object->VXsize * object->PixelBytes);
src.PixelBytes = object->PixelBytes;
color = htole32(color);
for (i = 0; i < object->VXsize; i++)
bcopy(&color, src.Bitmap + i * object->PixelBytes, object->PixelBytes);
for (i = 0; i < object->VYsize; i++)
__VGLBitmapCopy(&src, 0, 0, object, 0, i, object->VYsize, 1);
break;
case VIDBUF8X: