Skip to content

Commit

Permalink
Allow for more fine tuning of Duff's device routines
Browse files Browse the repository at this point in the history
  • Loading branch information
@ccawley2011 @slouken
ccawley2011 authored and slouken committed Oct 12, 2024
1 parent aebb64e commit fec006a
Show file tree
Hide file tree
Showing 4 changed files with 62 additions and 36 deletions.
46 changes: 36 additions & 10 deletions src/video/SDL_blit.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -610,6 +610,15 @@ extern SDL_BlitFunc SDL_CalculateBlitA(SDL_Surface *surface);
#else
#define USE_DUFFS_LOOP
#endif

#define DUFFS_LOOP1(pixel_copy_increment, width) \
{ \
int n; \
for (n = width; n > 0; --n) { \
pixel_copy_increment; \
} \
}

#ifdef USE_DUFFS_LOOP

// 8-times unrolled loop
Expand Down Expand Up @@ -666,8 +675,26 @@ extern SDL_BlitFunc SDL_CalculateBlitA(SDL_Surface *surface);
} \
}

// Use the 8-times version of the loop by default
// 2-times unrolled loop
#define DUFFS_LOOP2(pixel_copy_increment, width) \
{ \
int n = (width + 1) / 2; \
switch (width & 1) { \
case 0: \
do { \
pixel_copy_increment; \
SDL_FALLTHROUGH; \
case 1: \
pixel_copy_increment; \
} while (--n > 0); \
} \
}

// Use the 4-times version of the loop by default
#define DUFFS_LOOP(pixel_copy_increment, width) \
DUFFS_LOOP4(pixel_copy_increment, width)
// Use the 8-times version of the loop for simple routines
#define DUFFS_LOOP_TRIVIAL(pixel_copy_increment, width) \
DUFFS_LOOP8(pixel_copy_increment, width)

// Special version of Duff's device for even more optimization
Expand Down Expand Up @@ -701,20 +728,19 @@ extern SDL_BlitFunc SDL_CalculateBlitA(SDL_Surface *surface);

// Don't use Duff's device to unroll loops
#define DUFFS_LOOP(pixel_copy_increment, width) \
{ \
int n; \
for (n = width; n > 0; --n) { \
pixel_copy_increment; \
} \
}
DUFFS_LOOP1(pixel_copy_increment, width)
#define DUFFS_LOOP_TRIVIAL(pixel_copy_increment, width) \
DUFFS_LOOP1(pixel_copy_increment, width)
#define DUFFS_LOOP8(pixel_copy_increment, width) \
DUFFS_LOOP(pixel_copy_increment, width)
DUFFS_LOOP1(pixel_copy_increment, width)
#define DUFFS_LOOP4(pixel_copy_increment, width) \
DUFFS_LOOP(pixel_copy_increment, width)
DUFFS_LOOP1(pixel_copy_increment, width)
#define DUFFS_LOOP2(pixel_copy_increment, width) \
DUFFS_LOOP1(pixel_copy_increment, width)
#define DUFFS_LOOP_124(pixel_copy_increment1, \
pixel_copy_increment2, \
pixel_copy_increment4, width) \
DUFFS_LOOP(pixel_copy_increment1, width)
DUFFS_LOOP1(pixel_copy_increment1, width)

#endif // USE_DUFFS_LOOP

Expand Down
16 changes: 8 additions & 8 deletions src/video/SDL_blit_1.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -48,7 +48,7 @@ static void Blit1to1(SDL_BlitInfo *info)
while (height--) {
#ifdef USE_DUFFS_LOOP
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
*dst = map[*src];
}
Expand Down Expand Up @@ -100,7 +100,7 @@ static void Blit1to2(SDL_BlitInfo *info)
#ifdef USE_DUFFS_LOOP
while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
*(Uint16 *)dst = map[*src++];
dst += 2;
Expand Down Expand Up @@ -256,7 +256,7 @@ static void Blit1to4(SDL_BlitInfo *info)
while (height--) {
#ifdef USE_DUFFS_LOOP
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
*dst++ = map[*src++];
, width);
/* *INDENT-ON* */ // clang-format on
Expand Down Expand Up @@ -297,7 +297,7 @@ static void Blit1to1Key(SDL_BlitInfo *info)
if (palmap) {
while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
if ( *src != ckey ) {
*dst = palmap[*src];
Expand All @@ -313,7 +313,7 @@ static void Blit1to1Key(SDL_BlitInfo *info)
} else {
while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
if ( *src != ckey ) {
*dst = *src;
Expand Down Expand Up @@ -345,7 +345,7 @@ static void Blit1to2Key(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
if ( *src != ckey ) {
*dstp=palmap[*src];
Expand Down Expand Up @@ -408,7 +408,7 @@ static void Blit1to4Key(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
if ( *src != ckey ) {
*dstp = palmap[*src];
Expand Down Expand Up @@ -444,7 +444,7 @@ static void Blit1toNAlpha(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP4(
DUFFS_LOOP(
{
sR = srcpal[*src].r;
sG = srcpal[*src].g;
Expand Down
22 changes: 11 additions & 11 deletions src/video/SDL_blit_A.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -46,7 +46,7 @@ static void BlitNto1SurfaceAlpha(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP4(
DUFFS_LOOP(
{
DISEMBLE_RGB(src, srcbpp, srcfmt, Pixel, sR, sG, sB);
dR = dstpal[*dst].r;
Expand Down Expand Up @@ -91,7 +91,7 @@ static void BlitNto1PixelAlpha(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP4(
DUFFS_LOOP(
{
DISEMBLE_RGBA(src,srcbpp,srcfmt,Pixel,sR,sG,sB,sA);
dR = dstpal[*dst].r;
Expand Down Expand Up @@ -253,7 +253,7 @@ static void BlitRGBtoRGBSurfaceAlpha128(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP4({
DUFFS_LOOP({
Uint32 s = *srcp++;
Uint32 d = *dstp;
*dstp++ = ((((s & 0x00fefefe) + (d & 0x00fefefe)) >> 1)
Expand Down Expand Up @@ -283,7 +283,7 @@ static void BlitRGBtoRGBSurfaceAlpha(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP4({
DUFFS_LOOP({
s = *srcp;
d = *dstp;

Expand Down Expand Up @@ -705,7 +705,7 @@ static void Blit565to565SurfaceAlpha(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP4({
DUFFS_LOOP({
Uint32 s = *srcp++;
Uint32 d = *dstp;
/*
Expand Down Expand Up @@ -743,7 +743,7 @@ static void Blit555to555SurfaceAlpha(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP4({
DUFFS_LOOP({
Uint32 s = *srcp++;
Uint32 d = *dstp;
/*
Expand Down Expand Up @@ -776,7 +776,7 @@ static void BlitARGBto565PixelAlpha(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP4({
DUFFS_LOOP({
Uint32 s = *srcp;
unsigned alpha = s >> 27; // downscale alpha to 5 bits
/* Here we special-case opaque alpha since the
Expand Down Expand Up @@ -819,7 +819,7 @@ static void BlitARGBto555PixelAlpha(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP4({
DUFFS_LOOP({
unsigned alpha;
Uint32 s = *srcp;
alpha = s >> 27; // downscale alpha to 5 bits
Expand Down Expand Up @@ -872,7 +872,7 @@ static void BlitNtoNSurfaceAlpha(SDL_BlitInfo *info)
if (sA) {
while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP4(
DUFFS_LOOP(
{
DISEMBLE_RGB(src, srcbpp, srcfmt, Pixel, sR, sG, sB);
DISEMBLE_RGBA(dst, dstbpp, dstfmt, Pixel, dR, dG, dB, dA);
Expand Down Expand Up @@ -910,7 +910,7 @@ static void BlitNtoNSurfaceAlphaKey(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP4(
DUFFS_LOOP(
{
RETRIEVE_RGB_PIXEL(src, srcbpp, Pixel);
if (sA && Pixel != ckey) {
Expand Down Expand Up @@ -1302,7 +1302,7 @@ static void BlitNtoNPixelAlpha(SDL_BlitInfo *info)
dstbpp = dstfmt->bytes_per_pixel;

while (height--) {
DUFFS_LOOP4(
DUFFS_LOOP(
{
DISEMBLE_RGBA(src, srcbpp, srcfmt, Pixel, sR, sG, sB, sA);
if (sA) {
Expand Down
14 changes: 7 additions & 7 deletions src/video/SDL_blit_N.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1800,7 +1800,7 @@ static void Blit_RGB555_ARGB1555(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
*dst = *src | mask;
++dst;
Expand Down Expand Up @@ -1831,7 +1831,7 @@ static void Blit4to4MaskAlpha(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
*dst = *src | mask;
++dst;
Expand All @@ -1848,7 +1848,7 @@ static void Blit4to4MaskAlpha(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
*dst = *src & mask;
++dst;
Expand Down Expand Up @@ -2142,7 +2142,7 @@ static void Blit2to2Key(SDL_BlitInfo *info)

while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
if ( (*srcp & rgbmask) != ckey ) {
*dstp = *srcp;
Expand Down Expand Up @@ -2188,7 +2188,7 @@ static void BlitNtoNKey(SDL_BlitInfo *info)
Uint32 mask = ((Uint32)info->a) << dstfmt->Ashift;
while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
if ((*src32 & rgbmask) != ckey) {
*dst32 = *src32 | mask;
Expand All @@ -2206,7 +2206,7 @@ static void BlitNtoNKey(SDL_BlitInfo *info)
Uint32 mask = srcfmt->Rmask | srcfmt->Gmask | srcfmt->Bmask;
while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
if ((*src32 & rgbmask) != ckey) {
*dst32 = *src32 & mask;
Expand Down Expand Up @@ -2463,7 +2463,7 @@ static void BlitNtoNKeyCopyAlpha(SDL_BlitInfo *info)
Uint32 *dst32 = (Uint32 *)dst;
while (height--) {
/* *INDENT-OFF* */ // clang-format off
DUFFS_LOOP(
DUFFS_LOOP_TRIVIAL(
{
if ((*src32 & rgbmask) != ckey) {
*dst32 = *src32;
Expand Down

0 comments on commit fec006a

Please sign in to comment.