quakeforge/libs/video/renderer/sw/d_spr8.S
Bill Currie 0c437492b4 [renderer] Move to using dynamic frame buffers
For now, OpenGL and Vulkan renderers are broken as I focused on getting
the software renderer working (which was quite tricky to get right).

This fixes a couple of issues: the segfault when warping the screen (due
to the scene rendering move invalidating the warp buffer), and warp
always having 320x200 resolution. There's still the problem of the
effect being too subtle at high resolution, but that's just a matter of
updating the tables and tweaking the code in D_WarpScreen.

Another issue is the Draw functions should probably write directly to
the main frame buffer or even one passed in as a parameter. This would
remove the need for binding the main buffer at the beginning and end of
the frame.
2022-03-24 12:56:29 +09:00

915 lines
21 KiB
ArmAsm

/*
d_spr8.S
x86 assembly-language horizontal 8-bpp transparent span-drawing code.
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:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
$Id$
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "asm_i386.h"
#include "quakeasm.h"
#include "asm_draw.h"
#ifdef PIC
#undef USE_INTEL_ASM //XXX asm pic hack
#endif
#ifdef USE_INTEL_ASM
//----------------------------------------------------------------------
// 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 C(fp_8)
movl C(cacheblock),%edx
flds C(d_tdivzstepu)
fmuls C(fp_8)
movl pspans(%esp),%ebx // point to the first span descriptor
flds C(d_zistepu)
fmuls C(fp_8)
movl %edx,C(pbase) // pbase = cacheblock
flds C(d_zistepu)
fmuls C(fp_64kx64k)
fxch %st(3)
fstps C(sdivz8stepu)
fstps C(zi8stepu)
fstps C(tdivz8stepu)
fistpl C(izistep)
movl C(izistep),%eax
rorl $16,%eax // put upper 16 bits in low word
movl sspan_t_count(%ebx),%ecx
movl %eax,C(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 C(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 C(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 C(izi) // 0.32 fixed-point 1/z
movl C(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,C(izi)
movl sspan_t_u(%ebx),%ebp
imull C(d_zrowbytes)
shll $1,%ebp // a word per pixel
addl C(d_zbuffer),%eax
addl %ebp,%eax
movl %eax,C(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 * d_rowbytes
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,C(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 C(s) // 1/z | t | t/z | s/z
fistpl C(t) // 1/z | t/z | s/z
fildl C(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 C(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 C(s) // 1/z | t | t/z | s/z
fistpl C(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 C(s) // 1/z | t | t/z | s/z
fistpl C(t) // 1/z | t/z | s/z
fadds C(zi8stepu)
fxch %st(2)
fadds C(sdivz8stepu)
fxch %st(2)
flds C(tdivz8stepu)
faddp %st(0),%st(2)
flds C(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 C(s),%esi
addl C(t),%edx
movl C(bbextents),%ebx
movl C(bbextentt),%ebp
cmpl %ebx,%esi
ja LClampHighOrLow0
LClampReentry0:
movl %esi,C(s)
movl C(pbase),%ebx
shll $16,%esi
cmpl %ebp,%edx
movl %esi,C(sfracf)
ja LClampHighOrLow1
LClampReentry1:
movl %edx,C(t)
movl C(s),%esi // sfrac = scans->sfrac;
shll $16,%edx
movl C(t),%eax // tfrac = scans->tfrac;
sarl $16,%esi
movl %edx,C(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 C(snext)
fistpl C(tnext)
movl C(snext),%eax
movl C(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,C(snext)
movl %ecx,C(tnext)
subl C(s),%ebp
subl C(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 C(tfracf),%edx
movl %eax,C(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,C(sstep)
movl C(sfracf),%ebx
shll $13,%ecx // left-justify tstep fractional part
movl %eax,C(advancetable) // advance extra in t
movl %ecx,C(tstep)
movl C(pz),%ecx
movl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx // advance tfrac fractional part by tstep frac
sbbl %eax,%eax // turn tstep carry into -1 (0 if none)
addl C(sstep),%ebx // advance sfrac fractional part by sstep frac
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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,C(spancountminus1)
fildl C(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 C(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 C(zi8stepu)
fxch %st(2)
fadds C(sdivz8stepu)
fxch %st(2)
flds C(tdivz8stepu)
faddp %st(0),%st(2)
flds C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(advancetable)+4(,%eax,4),%esi
addl $8,%edi
addl $16,%ecx
movl %edx,C(tfracf)
movl C(snext),%edx
movl %ebx,C(sfracf)
movl C(tnext),%ebx
movl %edx,C(s)
movl %ebx,C(t)
movl %ecx,C(pz)
movl %ebp,C(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 C(snext)
fistpl C(tnext)
movl C(tadjust),%ebx
movl C(sadjust),%eax
addl C(snext),%eax
addl C(tnext),%ebx
movl C(bbextents),%ebp
movl C(bbextentt),%edx
cmpl $2048,%eax
jl LClampLow4
cmpl %ebp,%eax
ja LClampHigh4
LClampReentry4:
movl %eax,C(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 C(s),%eax
subl C(t),%ebx
addl %eax,%eax // convert to 15.17 format so multiply by 1.31
addl %ebx,%ebx // reciprocal yields 16.48
imull C(reciprocal_table)-8(,%ecx,4) // sstep = (snext - s) / (spancount-1)
movl %edx,%ebp
movl %ebx,%eax
imull C(reciprocal_table)-8(,%ecx,4) // tstep = (tnext - t) / (spancount-1)
LSetEntryvec:
//
// set up advancetable
//
movl C(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 C(tfracf),%ecx
movl %edx,C(advancetable)+4 // advance base in t
addl %ebx,%edx // ((tstep >> 16) + 1) * cachewidth +
// (sstep >> 16);
shll $16,%ebp // left-justify sstep fractional part
movl C(sfracf),%ebx
shll $16,%eax // left-justify tstep fractional part
movl %edx,C(advancetable) // advance extra in t
movl %eax,C(tstep)
movl %ebp,C(sstep)
movl %ecx,%edx
movl C(pz),%ecx
movl C(izi),%ebp
ret // jump to the number-of-pixels handler
//----------------------------------------
LNoSteps:
movl C(pz),%ecx
subl $7,%edi // adjust for hardwired offset
subl $14,%ecx
jmp LEndSpan
LOnlyOneStep:
subl C(s),%eax
subl C(t),%ebx
movl %eax,%ebp
movl %ebx,%edx
jmp LSetEntryvec
//----------------------------------------
.globl C(Spr8Entry2_8)
C(Spr8Entry2_8):
subl $6,%edi // adjust for hardwired offsets
subl $12,%ecx
movb (%esi),%al
jmp LLEntry2_8
//----------------------------------------
.globl C(Spr8Entry3_8)
C(Spr8Entry3_8):
subl $5,%edi // adjust for hardwired offsets
subl $10,%ecx
jmp LLEntry3_8
//----------------------------------------
.globl C(Spr8Entry4_8)
C(Spr8Entry4_8):
subl $4,%edi // adjust for hardwired offsets
subl $8,%ecx
jmp LLEntry4_8
//----------------------------------------
.globl C(Spr8Entry5_8)
C(Spr8Entry5_8):
subl $3,%edi // adjust for hardwired offsets
subl $6,%ecx
jmp LLEntry5_8
//----------------------------------------
.globl C(Spr8Entry6_8)
C(Spr8Entry6_8):
subl $2,%edi // adjust for hardwired offsets
subl $4,%ecx
jmp LLEntry6_8
//----------------------------------------
.globl C(Spr8Entry7_8)
C(Spr8Entry7_8):
decl %edi // adjust for hardwired offsets
subl $2,%ecx
jmp LLEntry7_8
//----------------------------------------
.globl C(Spr8Entry8_8)
C(Spr8Entry8_8):
cmpw (%ecx),%bp
jl Lp9
movb (%esi),%al
cmpb $(TRANSPARENT_COLOR),%al
jz Lp9
movw %bp,(%ecx)
movb %al,(%edi)
Lp9:
addl C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 C(izistep),%ebp
adcl $0,%ebp
addl C(tstep),%edx
sbbl %eax,%eax
addl C(sstep),%ebx
adcl C(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 // USE_INTEL_ASM
#if defined(__linux__) && defined(__ELF__)
.section .note.GNU-stack,"",%progbits
#endif