xorg-server-1.4/mfb/fastblt.h

   1 /*
   2
   3 Copyright 1989, 1998  The Open Group
   4
   5 Permission to use, copy, modify, distribute, and sell this software and its
   6 documentation for any purpose is hereby granted without fee, provided that
   7 the above copyright notice appear in all copies and that both that
   8 copyright notice and this permission notice appear in supporting
   9 documentation.
  10
  11 The above copyright notice and this permission notice shall be included
  12 in all copies or substantial portions of the Software.
  13
  14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  15 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  16 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  17 IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
  18 OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  19 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  20 OTHER DEALINGS IN THE SOFTWARE.
  21
  22 Except as contained in this notice, the name of The Open Group shall
  23 not be used in advertising or otherwise to promote the sale, use or
  24 other dealings in this Software without prior written authorization
  25 from The Open Group.
  26
  27 */
  28
  29 /*
  30  * Fast bitblt macros for certain hardware.  If your machine has an addressing
  31  * mode of small constant + register, you'll probably want this magic specific
  32  * code.  It's 25% faster for the R2000.  I haven't studied the Sparc
  33  * instruction set, but I suspect it also has this addressing mode.  Also,
  34  * unrolling the loop by 32 is possibly excessive for mfb. The number of times
  35  * the loop is actually looped through is pretty small.
  36  */
  37
  38 /*
  39  * WARNING:  These macros make *a lot* of assumptions about
  40  * the environment they are invoked in.  Plenty of implicit
  41  * arguments, lots of side effects.  Don't use them casually.
  42  */
  43
  44 #define SwitchOdd(n) case n: BodyOdd(n)
  45 #define SwitchEven(n) case n: BodyEven(n)
  46
  47 /* to allow mfb and cfb to share code... */
  48 #ifdef HAVE_DIX_CONFIG_H
  49 #include <dix-config.h>
  50 #endif
  51
  52 #ifndef BitRight
  53 #define BitRight(a,b) SCRRIGHT(a,b)
  54 #define BitLeft(a,b) SCRLEFT(a,b)
  55 #endif
  56
  57 #ifdef LARGE_INSTRUCTION_CACHE
  58 #define UNROLL 8
  59 #define PackedLoop \
  60     switch (nl & (UNROLL-1)) { \
  61     SwitchOdd( 7) SwitchEven( 6) SwitchOdd( 5) SwitchEven( 4) \
  62     SwitchOdd( 3) SwitchEven( 2) SwitchOdd( 1) \
  63     } \
  64     while ((nl -= UNROLL) >= 0) { \
  65         LoopReset \
  66         BodyEven( 8) \
  67         BodyOdd( 7) BodyEven( 6) BodyOdd( 5) BodyEven( 4) \
  68         BodyOdd( 3) BodyEven( 2) BodyOdd( 1) \
  69     }
  70 #else
  71 #define UNROLL 4
  72 #define PackedLoop \
  73     switch (nl & (UNROLL-1)) { \
  74     SwitchOdd( 3) SwitchEven( 2) SwitchOdd( 1) \
  75     } \
  76     while ((nl -= UNROLL) >= 0) { \
  77         LoopReset \
  78         BodyEven( 4) \
  79         BodyOdd( 3) BodyEven( 2) BodyOdd( 1) \
  80     }
  81 #endif
  82
  83 #define DuffL(counter,label,body) \
  84     switch (counter & 3) { \
  85     label: \
  86         body \
  87     case 3: \
  88         body \
  89     case 2: \
  90         body \
  91     case 1: \
  92         body \
  93     case 0: \
  94         if ((counter -= 4) >= 0) \
  95             goto label; \
  96     }