/*
Copyright (C) 1996-1997 Id Software, Inc.
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
//
// d_spr8.s
// x86 assembly-language horizontal 8-bpp transparent span-drawing code.
//
#include "asm_i386.h"
#include "quakeasm.h"
#include "asm_draw.h"
#if id386
//----------------------------------------------------------------------
// 8-bpp horizontal span drawing code for polygons, with transparency.
//----------------------------------------------------------------------
.text
// out-of-line, rarely-needed clamping code
LClampHigh0:
movl C(bbextents),%esi
jmp LClampReentry0
LClampHighOrLow0:
jg LClampHigh0
xorl %esi,%esi
jmp LClampReentry0
LClampHigh1:
movl C(bbextentt),%edx
jmp LClampReentry1
LClampHighOrLow1:
jg LClampHigh1
xorl %edx,%edx
jmp LClampReentry1
LClampLow2:
movl $2048,%ebp
jmp LClampReentry2
LClampHigh2:
movl C(bbextents),%ebp
jmp LClampReentry2
LClampLow3:
movl $2048,%ecx
jmp LClampReentry3
LClampHigh3:
movl C(bbextentt),%ecx
jmp LClampReentry3
LClampLow4:
movl $2048,%eax
jmp LClampReentry4
LClampHigh4:
movl C(bbextents),%eax
jmp LClampReentry4
LClampLow5:
movl $2048,%ebx
jmp LClampReentry5
LClampHigh5:
movl C(bbextentt),%ebx
jmp LClampReentry5
#define pspans 4+16
.align 4
.globl C(D_SpriteDrawSpans)
C(D_SpriteDrawSpans):
pushl %ebp // preserve caller's stack frame
pushl %edi
pushl %esi // preserve register variables
pushl %ebx
//
// set up scaled-by-8 steps, for 8-long segments; also set up cacheblock
// and span list pointers, and 1/z step in 0.32 fixed-point
//
// FIXME: any overlap from rearranging?
flds C(d_sdivzstepu)
fmuls fp_8
movl C(cacheblock),%edx
flds C(d_tdivzstepu)
fmuls fp_8
movl pspans(%esp),%ebx // point to the first span descriptor
flds C(d_zistepu)
fmuls fp_8
movl %edx,pbase // pbase = cacheblock
flds C(d_zistepu)
fmuls fp_64kx64k
fxch %st(3)
fstps sdivz8stepu
fstps zi8stepu
fstps tdivz8stepu
fistpl izistep
movl izistep,%eax
rorl $16,%eax // put upper 16 bits in low word
movl sspan_t_count(%ebx),%ecx
movl %eax,izistep
cmpl $0,%ecx
jle LNextSpan
LSpanLoop:
//
// set up the initial s/z, t/z, and 1/z on the FP stack, and generate the
// initial s and t values
//
// FIXME: pipeline FILD?
fildl sspan_t_v(%ebx)
fildl sspan_t_u(%ebx)
fld %st(1) // dv | du | dv
fmuls C(d_sdivzstepv) // dv*d_sdivzstepv | du | dv
fld %st(1) // du | dv*d_sdivzstepv | du | dv
fmuls C(d_sdivzstepu) // du*d_sdivzstepu | dv*d_sdivzstepv | du | dv
fld %st(2) // du | du*d_sdivzstepu | dv*d_sdivzstepv | du | dv
fmuls C(d_tdivzstepu) // du*d_tdivzstepu | du*d_sdivzstepu |
// dv*d_sdivzstepv | du | dv
fxch %st(1) // du*d_sdivzstepu | du*d_tdivzstepu |
// dv*d_sdivzstepv | du | dv
faddp %st(0),%st(2) // du*d_tdivzstepu |
// du*d_sdivzstepu + dv*d_sdivzstepv | du | dv
fxch %st(1) // du*d_sdivzstepu + dv*d_sdivzstepv |
// du*d_tdivzstepu | du | dv
fld %st(3) // dv | du*d_sdivzstepu + dv*d_sdivzstepv |
// du*d_tdivzstepu | du | dv
fmuls C(d_tdivzstepv) // dv*d_tdivzstepv |
// du*d_sdivzstepu + dv*d_sdivzstepv |
// du*d_tdivzstepu | du | dv
fxch %st(1) // du*d_sdivzstepu + dv*d_sdivzstepv |
// dv*d_tdivzstepv | du*d_tdivzstepu | du | dv
fadds C(d_sdivzorigin) // sdivz = d_sdivzorigin + dv*d_sdivzstepv +
// du*d_sdivzstepu; stays in %st(2) at end
fxch %st(4) // dv | dv*d_tdivzstepv | du*d_tdivzstepu | du |
// s/z
fmuls C(d_zistepv) // dv*d_zistepv | dv*d_tdivzstepv |
// du*d_tdivzstepu | du | s/z
fxch %st(1) // dv*d_tdivzstepv | dv*d_zistepv |
// du*d_tdivzstepu | du | s/z
faddp %st(0),%st(2) // dv*d_zistepv |
// dv*d_tdivzstepv + du*d_tdivzstepu | du | s/z
fxch %st(2) // du | dv*d_tdivzstepv + du*d_tdivzstepu |
// dv*d_zistepv | s/z
fmuls C(d_zistepu) // du*d_zistepu |
// dv*d_tdivzstepv + du*d_tdivzstepu |
// dv*d_zistepv | s/z
fxch %st(1) // dv*d_tdivzstepv + du*d_tdivzstepu |
// du*d_zistepu | dv*d_zistepv | s/z
fadds C(d_tdivzorigin) // tdivz = d_tdivzorigin + dv*d_tdivzstepv +
// du*d_tdivzstepu; stays in %st(1) at end
fxch %st(2) // dv*d_zistepv | du*d_zistepu | t/z | s/z
faddp %st(0),%st(1) // dv*d_zistepv + du*d_zistepu | t/z | s/z
flds fp_64k // fp_64k | dv*d_zistepv + du*d_zistepu | t/z | s/z
fxch %st(1) // dv*d_zistepv + du*d_zistepu | fp_64k | t/z | s/z
fadds C(d_ziorigin) // zi = d_ziorigin + dv*d_zistepv +
// du*d_zistepu; stays in %st(0) at end
// 1/z | fp_64k | t/z | s/z
fld %st(0) // FIXME: get rid of stall on FMUL?
fmuls fp_64kx64k
fxch %st(1)
//
// calculate and clamp s & t
//
fdivr %st(0),%st(2) // 1/z | z*64k | t/z | s/z
fxch %st(1)
fistpl izi // 0.32 fixed-point 1/z
movl izi,%ebp
//
// set pz to point to the first z-buffer pixel in the span
//
rorl $16,%ebp // put upper 16 bits in low word
movl sspan_t_v(%ebx),%eax
movl %ebp,izi
movl sspan_t_u(%ebx),%ebp
imull C(d_zrowbytes)
shll $1,%ebp // a word per pixel
addl C(d_pzbuffer),%eax
addl %ebp,%eax
movl %eax,pz
//
// point %edi to the first pixel in the span
//
movl C(d_viewbuffer),%ebp
movl sspan_t_v(%ebx),%eax
pushl %ebx // preserve spans pointer
movl C(tadjust),%edx
movl C(sadjust),%esi
movl C(d_scantable)(,%eax,4),%edi // v * screenwidth
addl %ebp,%edi
movl sspan_t_u(%ebx),%ebp
addl %ebp,%edi // pdest = &pdestspan[scans->u];
//
// now start the FDIV for the end of the span
//
cmpl $8,%ecx
ja LSetupNotLast1
decl %ecx
jz LCleanup1 // if only one pixel, no need to start an FDIV
movl %ecx,spancountminus1
// finish up the s and t calcs
fxch %st(1) // z*64k | 1/z | t/z | s/z
fld %st(0) // z*64k | z*64k | 1/z | t/z | s/z
fmul %st(4),%st(0) // s | z*64k | 1/z | t/z | s/z
fxch %st(1) // z*64k | s | 1/z | t/z | s/z
fmul %st(3),%st(0) // t | s | 1/z | t/z | s/z
fxch %st(1) // s | t | 1/z | t/z | s/z
fistpl s // 1/z | t | t/z | s/z
fistpl t // 1/z | t/z | s/z
fildl spancountminus1
flds C(d_tdivzstepu) // _d_tdivzstepu | spancountminus1
flds C(d_zistepu) // _d_zistepu | _d_tdivzstepu | spancountminus1
fmul %st(2),%st(0) // _d_zistepu*scm1 | _d_tdivzstepu | scm1
fxch %st(1) // _d_tdivzstepu | _d_zistepu*scm1 | scm1
fmul %st(2),%st(0) // _d_tdivzstepu*scm1 | _d_zistepu*scm1 | scm1
fxch %st(2) // scm1 | _d_zistepu*scm1 | _d_tdivzstepu*scm1
fmuls C(d_sdivzstepu) // _d_sdivzstepu*scm1 | _d_zistepu*scm1 |
// _d_tdivzstepu*scm1
fxch %st(1) // _d_zistepu*scm1 | _d_sdivzstepu*scm1 |
// _d_tdivzstepu*scm1
faddp %st(0),%st(3) // _d_sdivzstepu*scm1 | _d_tdivzstepu*scm1
fxch %st(1) // _d_tdivzstepu*scm1 | _d_sdivzstepu*scm1
faddp %st(0),%st(3) // _d_sdivzstepu*scm1
faddp %st(0),%st(3)
flds fp_64k
fdiv %st(1),%st(0) // this is what we've gone to all this trouble to
// overlap
jmp LFDIVInFlight1
LCleanup1:
// finish up the s and t calcs
fxch %st(1) // z*64k | 1/z | t/z | s/z
fld %st(0) // z*64k | z*64k | 1/z | t/z | s/z
fmul %st(4),%st(0) // s | z*64k | 1/z | t/z | s/z
fxch %st(1) // z*64k | s | 1/z | t/z | s/z
fmul %st(3),%st(0) // t | s | 1/z | t/z | s/z
fxch %st(1) // s | t | 1/z | t/z | s/z
fistpl s // 1/z | t | t/z | s/z
fistpl t // 1/z | t/z | s/z
jmp LFDIVInFlight1
.align 4
LSetupNotLast1:
// finish up the s and t calcs
fxch %st(1) // z*64k | 1/z | t/z | s/z
fld %st(0) // z*64k | z*64k | 1/z | t/z | s/z
fmul %st(4),%st(0) // s | z*64k | 1/z | t/z | s/z
fxch %st(1) // z*64k | s | 1/z | t/z | s/z
fmul %st(3),%st(0) // t | s | 1/z | t/z | s/z
fxch %st(1) // s | t | 1/z | t/z | s/z
fistpl s // 1/z | t | t/z | s/z
fistpl t // 1/z | t/z | s/z
fadds zi8stepu
fxch %st(2)
fadds sdivz8stepu
fxch %st(2)
flds tdivz8stepu
faddp %st(0),%st(2)
flds fp_64k
fdiv %st(1),%st(0) // z = 1/1/z
// this is what we've gone to all this trouble to
// overlap
LFDIVInFlight1:
addl s,%esi
addl t,%edx
movl C(bbextents),%ebx
movl C(bbextentt),%ebp
cmpl %ebx,%esi
ja LClampHighOrLow0
LClampReentry0:
movl %esi,s
movl pbase,%ebx
shll $16,%esi
cmpl %ebp,%edx
movl %esi,sfracf
ja LClampHighOrLow1
LClampReentry1:
movl %edx,t
movl s,%esi // sfrac = scans->sfrac;
shll $16,%edx
movl t,%eax // tfrac = scans->tfrac;
sarl $16,%esi
movl %edx,tfracf
//
// calculate the texture starting address
//
sarl $16,%eax
addl %ebx,%esi
imull C(cachewidth),%eax // (tfrac >> 16) * cachewidth
addl %eax,%esi // psource = pbase + (sfrac >> 16) +
// ((tfrac >> 16) * cachewidth);
//
// determine whether last span or not
//
cmpl $8,%ecx
jna LLastSegment
//
// not the last segment; do full 8-wide segment
//
LNotLastSegment:
//
// advance s/z, t/z, and 1/z, and calculate s & t at end of span and steps to
// get there
//
// pick up after the FDIV that was left in flight previously
fld %st(0) // duplicate it
fmul %st(4),%st(0) // s = s/z * z
fxch %st(1)
fmul %st(3),%st(0) // t = t/z * z
fxch %st(1)
fistpl snext
fistpl tnext
movl snext,%eax
movl tnext,%edx
subl $8,%ecx // count off this segments' pixels
movl C(sadjust),%ebp
pushl %ecx // remember count of remaining pixels
movl C(tadjust),%ecx
addl %eax,%ebp
addl %edx,%ecx
movl C(bbextents),%eax
movl C(bbextentt),%edx
cmpl $2048,%ebp
jl LClampLow2
cmpl %eax,%ebp
ja LClampHigh2
LClampReentry2:
cmpl $2048,%ecx
jl LClampLow3
cmpl %edx,%ecx
ja LClampHigh3
LClampReentry3:
movl %ebp,snext
movl %ecx,tnext
subl s,%ebp
subl t,%ecx
//
// set up advancetable
//
movl %ecx,%eax
movl %ebp,%edx
sarl $19,%edx // sstep >>= 16;
movl C(cachewidth),%ebx
sarl $19,%eax // tstep >>= 16;
jz LIsZero
imull %ebx,%eax // (tstep >> 16) * cachewidth;
LIsZero:
addl %edx,%eax // add in sstep
// (tstep >> 16) * cachewidth + (sstep >> 16);
movl tfracf,%edx
movl %eax,advancetable+4 // advance base in t
addl %ebx,%eax // ((tstep >> 16) + 1) * cachewidth +
// (sstep >> 16);
shll $13,%ebp // left-justify sstep fractional part
movl %ebp,sstep
movl sfracf,%ebx
shll $13,%ecx // left-justify tstep fractional part
movl %eax,advancetable // advance extra in t
movl %ecx,tstep
movl pz,%ecx
movl izi,%ebp
cmpw (%ecx),%bp
jl Lp1
movb (%esi),%al // get first source texel
cmpb $(TRANSPARENT_COLOR),%al
jz Lp1
movw %bp,(%ecx)
movb %al,(%edi) // store first dest pixel
Lp1:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx // advance tfrac fractional part by tstep frac
sbbl %eax,%eax // turn tstep carry into -1 (0 if none)
addl sstep,%ebx // advance sfrac fractional part by sstep frac
adcl advancetable+4(,%eax,4),%esi // point to next source texel
cmpw 2(%ecx),%bp
jl Lp2
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp2
movw %bp,2(%ecx)
movb %al,1(%edi)
Lp2:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
cmpw 4(%ecx),%bp
jl Lp3
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp3
movw %bp,4(%ecx)
movb %al,2(%edi)
Lp3:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
cmpw 6(%ecx),%bp
jl Lp4
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp4
movw %bp,6(%ecx)
movb %al,3(%edi)
Lp4:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
cmpw 8(%ecx),%bp
jl Lp5
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp5
movw %bp,8(%ecx)
movb %al,4(%edi)
Lp5:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
//
// start FDIV for end of next segment in flight, so it can overlap
//
popl %eax
cmpl $8,%eax // more than one segment after this?
ja LSetupNotLast2 // yes
decl %eax
jz LFDIVInFlight2 // if only one pixel, no need to start an FDIV
movl %eax,spancountminus1
fildl spancountminus1
flds C(d_zistepu) // _d_zistepu | spancountminus1
fmul %st(1),%st(0) // _d_zistepu*scm1 | scm1
flds C(d_tdivzstepu) // _d_tdivzstepu | _d_zistepu*scm1 | scm1
fmul %st(2),%st(0) // _d_tdivzstepu*scm1 | _d_zistepu*scm1 | scm1
fxch %st(1) // _d_zistepu*scm1 | _d_tdivzstepu*scm1 | scm1
faddp %st(0),%st(3) // _d_tdivzstepu*scm1 | scm1
fxch %st(1) // scm1 | _d_tdivzstepu*scm1
fmuls C(d_sdivzstepu) // _d_sdivzstepu*scm1 | _d_tdivzstepu*scm1
fxch %st(1) // _d_tdivzstepu*scm1 | _d_sdivzstepu*scm1
faddp %st(0),%st(3) // _d_sdivzstepu*scm1
flds fp_64k // 64k | _d_sdivzstepu*scm1
fxch %st(1) // _d_sdivzstepu*scm1 | 64k
faddp %st(0),%st(4) // 64k
fdiv %st(1),%st(0) // this is what we've gone to all this trouble to
// overlap
jmp LFDIVInFlight2
.align 4
LSetupNotLast2:
fadds zi8stepu
fxch %st(2)
fadds sdivz8stepu
fxch %st(2)
flds tdivz8stepu
faddp %st(0),%st(2)
flds fp_64k
fdiv %st(1),%st(0) // z = 1/1/z
// this is what we've gone to all this trouble to
// overlap
LFDIVInFlight2:
pushl %eax
cmpw 10(%ecx),%bp
jl Lp6
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp6
movw %bp,10(%ecx)
movb %al,5(%edi)
Lp6:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
cmpw 12(%ecx),%bp
jl Lp7
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp7
movw %bp,12(%ecx)
movb %al,6(%edi)
Lp7:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
cmpw 14(%ecx),%bp
jl Lp8
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp8
movw %bp,14(%ecx)
movb %al,7(%edi)
Lp8:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
addl $8,%edi
addl $16,%ecx
movl %edx,tfracf
movl snext,%edx
movl %ebx,sfracf
movl tnext,%ebx
movl %edx,s
movl %ebx,t
movl %ecx,pz
movl %ebp,izi
popl %ecx // retrieve count
//
// determine whether last span or not
//
cmpl $8,%ecx // are there multiple segments remaining?
ja LNotLastSegment // yes
//
// last segment of scan
//
LLastSegment:
//
// advance s/z, t/z, and 1/z, and calculate s & t at end of span and steps to
// get there. The number of pixels left is variable, and we want to land on the
// last pixel, not step one past it, so we can't run into arithmetic problems
//
testl %ecx,%ecx
jz LNoSteps // just draw the last pixel and we're done
// pick up after the FDIV that was left in flight previously
fld %st(0) // duplicate it
fmul %st(4),%st(0) // s = s/z * z
fxch %st(1)
fmul %st(3),%st(0) // t = t/z * z
fxch %st(1)
fistpl snext
fistpl tnext
movl C(tadjust),%ebx
movl C(sadjust),%eax
addl snext,%eax
addl tnext,%ebx
movl C(bbextents),%ebp
movl C(bbextentt),%edx
cmpl $2048,%eax
jl LClampLow4
cmpl %ebp,%eax
ja LClampHigh4
LClampReentry4:
movl %eax,snext
cmpl $2048,%ebx
jl LClampLow5
cmpl %edx,%ebx
ja LClampHigh5
LClampReentry5:
cmpl $1,%ecx // don't bother
je LOnlyOneStep // if two pixels in segment, there's only one step,
// of the segment length
subl s,%eax
subl t,%ebx
addl %eax,%eax // convert to 15.17 format so multiply by 1.31
addl %ebx,%ebx // reciprocal yields 16.48
imull reciprocal_table-8(,%ecx,4) // sstep = (snext - s) / (spancount-1)
movl %edx,%ebp
movl %ebx,%eax
imull reciprocal_table-8(,%ecx,4) // tstep = (tnext - t) / (spancount-1)
LSetEntryvec:
//
// set up advancetable
//
movl spr8entryvec_table(,%ecx,4),%ebx
movl %edx,%eax
pushl %ebx // entry point into code for RET later
movl %ebp,%ecx
sarl $16,%ecx // sstep >>= 16;
movl C(cachewidth),%ebx
sarl $16,%edx // tstep >>= 16;
jz LIsZeroLast
imull %ebx,%edx // (tstep >> 16) * cachewidth;
LIsZeroLast:
addl %ecx,%edx // add in sstep
// (tstep >> 16) * cachewidth + (sstep >> 16);
movl tfracf,%ecx
movl %edx,advancetable+4 // advance base in t
addl %ebx,%edx // ((tstep >> 16) + 1) * cachewidth +
// (sstep >> 16);
shll $16,%ebp // left-justify sstep fractional part
movl sfracf,%ebx
shll $16,%eax // left-justify tstep fractional part
movl %edx,advancetable // advance extra in t
movl %eax,tstep
movl %ebp,sstep
movl %ecx,%edx
movl pz,%ecx
movl izi,%ebp
ret // jump to the number-of-pixels handler
//----------------------------------------
LNoSteps:
movl pz,%ecx
subl $7,%edi // adjust for hardwired offset
subl $14,%ecx
jmp LEndSpan
LOnlyOneStep:
subl s,%eax
subl t,%ebx
movl %eax,%ebp
movl %ebx,%edx
jmp LSetEntryvec
//----------------------------------------
.globl Spr8Entry2_8
Spr8Entry2_8:
subl $6,%edi // adjust for hardwired offsets
subl $12,%ecx
movb (%esi),%al
jmp LLEntry2_8
//----------------------------------------
.globl Spr8Entry3_8
Spr8Entry3_8:
subl $5,%edi // adjust for hardwired offsets
subl $10,%ecx
jmp LLEntry3_8
//----------------------------------------
.globl Spr8Entry4_8
Spr8Entry4_8:
subl $4,%edi // adjust for hardwired offsets
subl $8,%ecx
jmp LLEntry4_8
//----------------------------------------
.globl Spr8Entry5_8
Spr8Entry5_8:
subl $3,%edi // adjust for hardwired offsets
subl $6,%ecx
jmp LLEntry5_8
//----------------------------------------
.globl Spr8Entry6_8
Spr8Entry6_8:
subl $2,%edi // adjust for hardwired offsets
subl $4,%ecx
jmp LLEntry6_8
//----------------------------------------
.globl Spr8Entry7_8
Spr8Entry7_8:
decl %edi // adjust for hardwired offsets
subl $2,%ecx
jmp LLEntry7_8
//----------------------------------------
.globl Spr8Entry8_8
Spr8Entry8_8:
cmpw (%ecx),%bp
jl Lp9
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp9
movw %bp,(%ecx)
movb %al,(%edi)
Lp9:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
LLEntry7_8:
cmpw 2(%ecx),%bp
jl Lp10
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp10
movw %bp,2(%ecx)
movb %al,1(%edi)
Lp10:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
LLEntry6_8:
cmpw 4(%ecx),%bp
jl Lp11
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp11
movw %bp,4(%ecx)
movb %al,2(%edi)
Lp11:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
LLEntry5_8:
cmpw 6(%ecx),%bp
jl Lp12
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp12
movw %bp,6(%ecx)
movb %al,3(%edi)
Lp12:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
LLEntry4_8:
cmpw 8(%ecx),%bp
jl Lp13
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp13
movw %bp,8(%ecx)
movb %al,4(%edi)
Lp13:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
LLEntry3_8:
cmpw 10(%ecx),%bp
jl Lp14
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp14
movw %bp,10(%ecx)
movb %al,5(%edi)
Lp14:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
LLEntry2_8:
cmpw 12(%ecx),%bp
jl Lp15
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp15
movw %bp,12(%ecx)
movb %al,6(%edi)
Lp15:
addl izistep,%ebp
adcl $0,%ebp
addl tstep,%edx
sbbl %eax,%eax
addl sstep,%ebx
adcl advancetable+4(,%eax,4),%esi
LEndSpan:
cmpw 14(%ecx),%bp
jl Lp16
movb (%esi),%al // load first texel in segment
cmpb $(TRANSPARENT_COLOR),%al
jz Lp16
movw %bp,14(%ecx)
movb %al,7(%edi)
Lp16:
//
// clear s/z, t/z, 1/z from FP stack
//
fstp %st(0)
fstp %st(0)
fstp %st(0)
popl %ebx // restore spans pointer
LNextSpan:
addl $(sspan_t_size),%ebx // point to next span
movl sspan_t_count(%ebx),%ecx
cmpl $0,%ecx // any more spans?
jg LSpanLoop // yes
jz LNextSpan // yes, but this one's empty
popl %ebx // restore register variables
popl %esi
popl %edi
popl %ebp // restore the caller's stack frame
ret
#endif // id386