Merge r1.36 of fbcompose.c from xserver CVS: Special case projective

    transforms so we can avoid doing the expensive
64-bit math. Unroll the bilinear interpolation loops for an extra boost. I
    tested this with the up/downscaling cairo-benchmarks with Xvfb and saw
    a 12% +/- 4% decrease in time taken to run them.

1 files changed, 158 insertions, 78 deletions

diff --git a/fb/fbcompose.c b/fb/fbcompose.c
index 66483501c..f85a5ad79 100644
--- a/fb/fbcompose.c
+++ b/fb/fbcompose.c
@@ -1,5 +1,5 @@
 /*
- * $XdotOrg: xc/programs/Xserver/fb/fbcompose.c,v 1.20 2005/08/30 03:01:38 anholt Exp $
+ * $XdotOrg: xc/programs/Xserver/fb/fbcompose.c,v 1.22 2005/09/07 01:30:23 daniels Exp $
  * $XFree86: xc/programs/Xserver/fb/fbcompose.c,v 1.17tsi Exp $
  *
  * Copyright © 2000 Keith Packard, member of The XFree86 Project, Inc.
@@ -2867,6 +2867,7 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
     int         i;
     BoxRec	box;
     miIndexedPtr indexed = (miIndexedPtr) pict->pFormat->index.devPrivate;
+    Bool projective = FALSE;
 
     fetch = fetchPixelProcForPicture(pict);
 
@@ -2890,6 +2891,7 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
         unit.vector[1] = 0;
         unit.vector[2] = 0;
     }
+    projective = (unit.vector[2] != 0);
 
     if (pict->filter == PictFilterNearest)
     {
@@ -2900,8 +2902,13 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                     if (!v.vector[2]) {
                         buffer[i] = 0;
                     } else {
-                        y = MOD(DIV(v.vector[1],v.vector[2]), pict->pDrawable->height);
-                        x = MOD(DIV(v.vector[0],v.vector[2]), pict->pDrawable->width);
+                        if (projective) {
+                            y = MOD(DIV(v.vector[1],v.vector[2]), pict->pDrawable->height);
+                            x = MOD(DIV(v.vector[0],v.vector[2]), pict->pDrawable->width);
+                        } else {
+                            y = MOD(v.vector[1]>>16, pict->pDrawable->height);
+                            x = MOD(v.vector[0]>>16, pict->pDrawable->width);
+                        }
                         buffer[i] = fetch(bits + (y + pict->pDrawable->y)*stride, x + pict->pDrawable->x, indexed);
                     }
                     v.vector[0] += unit.vector[0];
@@ -2913,8 +2920,13 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                     if (!v.vector[2]) {
                         buffer[i] = 0;
                     } else {
-                        y = MOD(DIV(v.vector[1],v.vector[2]), pict->pDrawable->height);
-                        x = MOD(DIV(v.vector[0],v.vector[2]), pict->pDrawable->width);
+                        if (projective) {
+                            y = MOD(DIV(v.vector[1],v.vector[2]), pict->pDrawable->height);
+                            x = MOD(DIV(v.vector[0],v.vector[2]), pict->pDrawable->width);
+                        } else {
+                            y = MOD(v.vector[1]>>16, pict->pDrawable->height);
+                            x = MOD(v.vector[0]>>16, pict->pDrawable->width);
+                        }
                         if (POINT_IN_REGION (0, pict->pCompositeClip, x, y, &box))
                             buffer[i] = fetch(bits + (y + pict->pDrawable->y)*stride, x + pict->pDrawable->x, indexed);
                         else
@@ -2932,8 +2944,13 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                     if (!v.vector[2]) {
                         buffer[i] = 0;
                     } else {
-                        y = DIV(v.vector[1],v.vector[2]);
-                        x = DIV(v.vector[0],v.vector[2]);
+                        if (projective) {
+                            y = DIV(v.vector[1],v.vector[2]);
+                            x = DIV(v.vector[0],v.vector[2]);
+                        } else {
+                            y = v.vector[1]>>16;
+                            x = v.vector[0]>>16;
+                        }
                         buffer[i] = ((x < box.x1) | (x >= box.x2) | (y < box.y1) | (y >= box.y2)) ?
                                     0 : fetch(bits + (y + pict->pDrawable->y)*stride, x + pict->pDrawable->x, indexed);
                     }
@@ -2946,8 +2963,13 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                     if (!v.vector[2]) {
                         buffer[i] = 0;
                     } else {
-                        y = DIV(v.vector[1],v.vector[2]);
-                        x = DIV(v.vector[0],v.vector[2]);
+                        if (projective) {
+                            y = DIV(v.vector[1],v.vector[2]);
+                            x = DIV(v.vector[0],v.vector[2]);
+                        } else {
+                            y = v.vector[1]>>16;
+                            x = v.vector[0]>>16;
+                        }
                         if (POINT_IN_REGION (0, pict->pCompositeClip, x, y, &box))
                             buffer[i] = fetch(bits + (y + pict->pDrawable->y)*stride, x + pict->pDrawable->x, indexed);
                         else
@@ -2967,19 +2989,27 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                     if (!v.vector[2]) {
                         buffer[i] = 0;
                     } else {
-                        int x1, x2, y1, y2, distx, idistx, disty, idisty, k;
+                        int x1, x2, y1, y2, distx, idistx, disty, idisty;
                         FbBits *b;
                         CARD32 tl, tr, bl, br, r;
-                        xFixed_48_16 div;
-
-                        div = ((xFixed_48_16)v.vector[0] << 16)/v.vector[2];
-                        x1 = div >> 16;
-                        distx = ((xFixed)div >> 8) & 0xff;
+                        CARD32 ft, fb;
+
+                        if (projective) {
+                            xFixed_48_16 div;
+                            div = ((xFixed_48_16)v.vector[0] << 16)/v.vector[2];
+                            x1 = div >> 16;
+                            distx = ((xFixed)div >> 8) & 0xff;
+                            div = ((xFixed_48_16)v.vector[1] << 16)/v.vector[2];
+                            y1 = div >> 16;
+                            disty = ((xFixed)div >> 8) & 0xff;
+                        } else {
+                            x1 = v.vector[0] >> 16;
+                            distx = (v.vector[0] >> 8) & 0xff;
+                            y1 = v.vector[1] >> 16;
+                            disty = (v.vector[1] >> 8) & 0xff;
+                        }
                         x2 = x1 + 1;
-                        div = ((xFixed_48_16)v.vector[1] << 16)/v.vector[2];
-                        y1 = div >> 16;
                         y2 = y1 + 1;
-                        disty = ((xFixed)div >> 8) & 0xff;
 
                         idistx = 256 - distx;
                         idisty = 256 - disty;
@@ -2997,13 +3027,18 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                         bl = fetch(b, x1 + pict->pDrawable->x, indexed);
                         br = fetch(b, x2 + pict->pDrawable->x, indexed);
 
-                        r = 0;
-                        for (k = 0; k < 32; k += 8) {
-                            CARD32 t, b;
-                            t = FbGet8(tl,k) * idistx + FbGet8(tr,k) * distx;
-                            b = FbGet8(bl,k) * idistx + FbGet8(br,k) * distx;
-                            r |= ((((t * idisty) + (b * disty)) >> 16) & 0xff) << k;
-                        }
+                        ft = FbGet8(tl,0) * idistx + FbGet8(tr,0) * distx;
+                        fb = FbGet8(bl,0) * idistx + FbGet8(br,0) * distx;
+                        r = (((ft * idisty + fb * disty) >> 16) & 0xff);
+                        ft = FbGet8(tl,8) * idistx + FbGet8(tr,8) * distx;
+                        fb = FbGet8(bl,8) * idistx + FbGet8(br,8) * distx;
+                        r |= (((ft * idisty + fb * disty) >> 8) & 0xff00);
+                        ft = FbGet8(tl,16) * idistx + FbGet8(tr,16) * distx;
+                        fb = FbGet8(bl,16) * idistx + FbGet8(br,16) * distx;
+                        r |= (((ft * idisty + fb * disty)) & 0xff0000);
+                        ft = FbGet8(tl,24) * idistx + FbGet8(tr,24) * distx;
+                        fb = FbGet8(bl,24) * idistx + FbGet8(br,24) * distx;
+                        r |= (((ft * idisty + fb * disty) << 8) & 0xff000000);
                         buffer[i] = r;
                     }
                     v.vector[0] += unit.vector[0];
@@ -3015,19 +3050,27 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                     if (!v.vector[2]) {
                         buffer[i] = 0;
                     } else {
-                        int x1, x2, y1, y2, distx, idistx, disty, idisty, k;
+                        int x1, x2, y1, y2, distx, idistx, disty, idisty;
                         FbBits *b;
                         CARD32 tl, tr, bl, br, r;
-                        xFixed_48_16 div;
-
-                        div = ((xFixed_48_16)v.vector[0] << 16)/v.vector[2];
-                        x1 = div >> 16;
-                        distx = ((xFixed)div >> 8) & 0xff;
+                        CARD32 ft, fb;
+
+                        if (projective) {
+                            xFixed_48_16 div;
+                            div = ((xFixed_48_16)v.vector[0] << 16)/v.vector[2];
+                            x1 = div >> 16;
+                            distx = ((xFixed)div >> 8) & 0xff;
+                            div = ((xFixed_48_16)v.vector[1] << 16)/v.vector[2];
+                            y1 = div >> 16;
+                            disty = ((xFixed)div >> 8) & 0xff;
+                        } else {
+                            x1 = v.vector[0] >> 16;
+                            distx = (v.vector[0] >> 8) & 0xff;
+                            y1 = v.vector[1] >> 16;
+                            disty = (v.vector[1] >> 8) & 0xff;
+                        }
                         x2 = x1 + 1;
-                        div = ((xFixed_48_16)v.vector[1] << 16)/v.vector[2];
-                        y1 = div >> 16;
                         y2 = y1 + 1;
-                        disty = ((xFixed)div >> 8) & 0xff;
 
                         idistx = 256 - distx;
                         idisty = 256 - disty;
@@ -3049,13 +3092,18 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                         br = POINT_IN_REGION(0, pict->pCompositeClip, x2, y2, &box)
                              ? fetch(b, x2 + pict->pDrawable->x, indexed) : 0;
 
-                        r = 0;
-                        for (k = 0; k < 32; k += 8) {
-                            CARD32 t, b;
-                            t = FbGet8(tl,k) * idistx + FbGet8(tr,k) * distx;
-                            b = FbGet8(bl,k) * idistx + FbGet8(br,k) * distx;
-                            r |= ((((t * idisty) + (b * disty)) >> 16) & 0xff) << k;
-                        }
+                        ft = FbGet8(tl,0) * idistx + FbGet8(tr,0) * distx;
+                        fb = FbGet8(bl,0) * idistx + FbGet8(br,0) * distx;
+                        r = (((ft * idisty + fb * disty) >> 16) & 0xff);
+                        ft = FbGet8(tl,8) * idistx + FbGet8(tr,8) * distx;
+                        fb = FbGet8(bl,8) * idistx + FbGet8(br,8) * distx;
+                        r |= (((ft * idisty + fb * disty) >> 8) & 0xff00);
+                        ft = FbGet8(tl,16) * idistx + FbGet8(tr,16) * distx;
+                        fb = FbGet8(bl,16) * idistx + FbGet8(br,16) * distx;
+                        r |= (((ft * idisty + fb * disty)) & 0xff0000);
+                        ft = FbGet8(tl,24) * idistx + FbGet8(tr,24) * distx;
+                        fb = FbGet8(bl,24) * idistx + FbGet8(br,24) * distx;
+                        r |= (((ft * idisty + fb * disty) << 8) & 0xff000000);
                         buffer[i] = r;
                     }
                     v.vector[0] += unit.vector[0];
@@ -3070,20 +3118,28 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                     if (!v.vector[2]) {
                         buffer[i] = 0;
                     } else {
-                        int x1, x2, y1, y2, distx, idistx, disty, idisty, x_off, k;
+                        int x1, x2, y1, y2, distx, idistx, disty, idisty, x_off;
                         FbBits *b;
                         CARD32 tl, tr, bl, br, r;
                         Bool x1_out, x2_out, y1_out, y2_out;
-                        xFixed_48_16 div;
-
-                        div = ((xFixed_48_16)v.vector[0] << 16)/v.vector[2];
-                        x1 = div >> 16;
-                        distx = ((xFixed)div >> 8) & 0xff;
+                        CARD32 ft, fb;
+
+                        if (projective) {
+                            xFixed_48_16 div;
+                            div = ((xFixed_48_16)v.vector[0] << 16)/v.vector[2];
+                            x1 = div >> 16;
+                            distx = ((xFixed)div >> 8) & 0xff;
+                            div = ((xFixed_48_16)v.vector[1] << 16)/v.vector[2];
+                            y1 = div >> 16;
+                            disty = ((xFixed)div >> 8) & 0xff;
+                        } else {
+                            x1 = v.vector[0] >> 16;
+                            distx = (v.vector[0] >> 8) & 0xff;
+                            y1 = v.vector[1] >> 16;
+                            disty = (v.vector[1] >> 8) & 0xff;
+                        }
                         x2 = x1 + 1;
-                        div = ((xFixed_48_16)v.vector[1] << 16)/v.vector[2];
-                        y1 = div >> 16;
                         y2 = y1 + 1;
-                        disty = ((xFixed)div >> 8) & 0xff;
 
                         idistx = 256 - distx;
                         idisty = 256 - disty;
@@ -3102,13 +3158,18 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                         bl = x1_out|y2_out ? 0 : fetch(b, x_off, indexed);
                         br = x2_out|y2_out ? 0 : fetch(b, x_off + 1, indexed);
 
-                        r = 0;
-                        for (k = 0; k < 32; k += 8) {
-                            CARD32 t, b;
-                            t = FbGet8(tl,k) * idistx + FbGet8(tr,k) * distx;
-                            b = FbGet8(bl,k) * idistx + FbGet8(br,k) * distx;
-                            r |= ((((t * idisty) + (b * disty)) >> 16) & 0xff) << k;
-                        }
+                        ft = FbGet8(tl,0) * idistx + FbGet8(tr,0) * distx;
+                        fb = FbGet8(bl,0) * idistx + FbGet8(br,0) * distx;
+                        r = (((ft * idisty + fb * disty) >> 16) & 0xff);
+                        ft = FbGet8(tl,8) * idistx + FbGet8(tr,8) * distx;
+                        fb = FbGet8(bl,8) * idistx + FbGet8(br,8) * distx;
+                        r |= (((ft * idisty + fb * disty) >> 8) & 0xff00);
+                        ft = FbGet8(tl,16) * idistx + FbGet8(tr,16) * distx;
+                        fb = FbGet8(bl,16) * idistx + FbGet8(br,16) * distx;
+                        r |= (((ft * idisty + fb * disty)) & 0xff0000);
+                        ft = FbGet8(tl,24) * idistx + FbGet8(tr,24) * distx;
+                        fb = FbGet8(bl,24) * idistx + FbGet8(br,24) * distx;
+                        r |= (((ft * idisty + fb * disty) << 8) & 0xff000000);
                         buffer[i] = r;
                     }
                     v.vector[0] += unit.vector[0];
@@ -3120,19 +3181,27 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                     if (!v.vector[2]) {
                         buffer[i] = 0;
                     } else {
-                        int x1, x2, y1, y2, distx, idistx, disty, idisty, x_off, k;
+                        int x1, x2, y1, y2, distx, idistx, disty, idisty, x_off;
                         FbBits *b;
                         CARD32 tl, tr, bl, br, r;
-                        xFixed_48_16 div;
-
-                        div = ((xFixed_48_16)v.vector[0] << 16)/v.vector[2];
-                        x1 = div >> 16;
-                        distx = ((xFixed)div >> 8) & 0xff;
+                        CARD32 ft, fb;
+
+                        if (projective) {
+                            xFixed_48_16 div;
+                            div = ((xFixed_48_16)v.vector[0] << 16)/v.vector[2];
+                            x1 = div >> 16;
+                            distx = ((xFixed)div >> 8) & 0xff;
+                            div = ((xFixed_48_16)v.vector[1] << 16)/v.vector[2];
+                            y1 = div >> 16;
+                            disty = ((xFixed)div >> 8) & 0xff;
+                        } else {
+                            x1 = v.vector[0] >> 16;
+                            distx = (v.vector[0] >> 8) & 0xff;
+                            y1 = v.vector[1] >> 16;
+                            disty = (v.vector[1] >> 8) & 0xff;
+                        }
                         x2 = x1 + 1;
-                        div = ((xFixed_48_16)v.vector[1] << 16)/v.vector[2];
-                        y1 = div >> 16;
                         y2 = y1 + 1;
-                        disty = ((xFixed)div >> 8) & 0xff;
 
                         idistx = 256 - distx;
                         idisty = 256 - disty;
@@ -3150,13 +3219,18 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                         br = POINT_IN_REGION(0, pict->pCompositeClip, x2, y2, &box)
                              ? fetch(b, x_off + 1, indexed) : 0;
 
-                        r = 0;
-                        for (k = 0; k < 32; k += 8) {
-                            CARD32 t, b;
-                            t = FbGet8(tl,k) * idistx + FbGet8(tr,k) * distx;
-                            b = FbGet8(bl,k) * idistx + FbGet8(br,k) * distx;
-                            r |= ((((t * idisty) + (b * disty)) >> 16) & 0xff) << k;
-                        }
+                        ft = FbGet8(tl,0) * idistx + FbGet8(tr,0) * distx;
+                        fb = FbGet8(bl,0) * idistx + FbGet8(br,0) * distx;
+                        r = (((ft * idisty + fb * disty) >> 16) & 0xff);
+                        ft = FbGet8(tl,8) * idistx + FbGet8(tr,8) * distx;
+                        fb = FbGet8(bl,8) * idistx + FbGet8(br,8) * distx;
+                        r |= (((ft * idisty + fb * disty) >> 8) & 0xff00);
+                        ft = FbGet8(tl,16) * idistx + FbGet8(tr,16) * distx;
+                        fb = FbGet8(bl,16) * idistx + FbGet8(br,16) * distx;
+                        r |= (((ft * idisty + fb * disty)) & 0xff0000);
+                        ft = FbGet8(tl,24) * idistx + FbGet8(tr,24) * distx;
+                        fb = FbGet8(bl,24) * idistx + FbGet8(br,24) * distx;
+                        r |= (((ft * idisty + fb * disty) << 8) & 0xff000000);
                         buffer[i] = r;
                     }
                     v.vector[0] += unit.vector[0];
@@ -3179,12 +3253,18 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32
                 int x1, x2, y1, y2, x, y;
                 INT32 srtot, sgtot, sbtot, satot;
                 xFixed *p = params;
-                xFixed_48_16 tmp;
-                tmp = ((xFixed_48_16)v.vector[0] << 16)/v.vector[2] - xoff;
-                x1 = xFixedToInt(tmp);
+
+                if (projective) {
+                    xFixed_48_16 tmp;
+                    tmp = ((xFixed_48_16)v.vector[0] << 16)/v.vector[2] - xoff;
+                    x1 = xFixedToInt(tmp);
+                    tmp = ((xFixed_48_16)v.vector[1] << 16)/v.vector[2] - yoff;
+                    y1 = xFixedToInt(tmp);
+                } else {
+                    x1 = xFixedToInt(v.vector[0] - xoff);
+                    y1 = xFixedToInt(v.vector[1] - yoff);
+                }
                 x2 = x1 + cwidth;
-                tmp = ((xFixed_48_16)v.vector[1] << 16)/v.vector[2] - yoff;
-                y1 = xFixedToInt(tmp);
                 y2 = y1 + cheight;
 
                 srtot = sgtot = sbtot = satot = 0;