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1039 lines
24 KiB
ArmAsm
1039 lines
24 KiB
ArmAsm
/*
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Copyright (C) 1996-1997 Id Software, Inc.
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Copyright (C) 1999,2000 contributors of the QuakeForge project
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Please see the file "AUTHORS" for a list of contributors
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This program is free software; you can redistribute it and/or
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modify it under the terms of the GNU General Public License
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as published by the Free Software Foundation; either version 2
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of the License, or (at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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See the GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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//
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// d_draw.s
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// x86 assembly-language horizontal 8-bpp span-drawing code.
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//
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#include "asm_i386.h"
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#include "quakeasm.h"
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#include "asm_draw.h"
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#include "d_ifacea.h"
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#if id386
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//----------------------------------------------------------------------
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// 8-bpp horizontal span drawing code for polygons, with no transparency.
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//
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// Assumes there is at least one span in pspans, and that every span
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// contains at least one pixel
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//----------------------------------------------------------------------
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.text
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// out-of-line, rarely-needed clamping code
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LClampHigh0:
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movl C(bbextents),%esi
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jmp LClampReentry0
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LClampHighOrLow0:
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jg LClampHigh0
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xorl %esi,%esi
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jmp LClampReentry0
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LClampHigh1:
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movl C(bbextentt),%edx
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jmp LClampReentry1
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LClampHighOrLow1:
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jg LClampHigh1
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xorl %edx,%edx
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jmp LClampReentry1
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LClampLow2:
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movl $2048,%ebp
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jmp LClampReentry2
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LClampHigh2:
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movl C(bbextents),%ebp
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jmp LClampReentry2
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LClampLow3:
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movl $2048,%ecx
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jmp LClampReentry3
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LClampHigh3:
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movl C(bbextentt),%ecx
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jmp LClampReentry3
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LClampLow4:
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movl $2048,%eax
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jmp LClampReentry4
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LClampHigh4:
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movl C(bbextents),%eax
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jmp LClampReentry4
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LClampLow5:
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movl $2048,%ebx
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jmp LClampReentry5
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LClampHigh5:
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movl C(bbextentt),%ebx
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jmp LClampReentry5
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#define pspans 4+16
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.align 4
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.globl C(D_DrawSpans8)
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C(D_DrawSpans8):
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pushl %ebp // preserve caller's stack frame
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pushl %edi
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pushl %esi // preserve register variables
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pushl %ebx
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//
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// set up scaled-by-8 steps, for 8-long segments; also set up cacheblock
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// and span list pointers
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//
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// TODO: any overlap from rearranging?
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flds C(d_sdivzstepu)
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fmuls fp_8
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movl C(cacheblock),%edx
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flds C(d_tdivzstepu)
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fmuls fp_8
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movl pspans(%esp),%ebx // point to the first span descriptor
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flds C(d_zistepu)
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fmuls fp_8
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movl %edx,pbase // pbase = cacheblock
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fstps zi8stepu
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fstps tdivz8stepu
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fstps sdivz8stepu
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LSpanLoop:
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//
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// set up the initial s/z, t/z, and 1/z on the FP stack, and generate the
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// initial s and t values
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//
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// FIXME: pipeline FILD?
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fildl espan_t_v(%ebx)
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fildl espan_t_u(%ebx)
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fld %st(1) // dv | du | dv
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fmuls C(d_sdivzstepv) // dv*d_sdivzstepv | du | dv
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fld %st(1) // du | dv*d_sdivzstepv | du | dv
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fmuls C(d_sdivzstepu) // du*d_sdivzstepu | dv*d_sdivzstepv | du | dv
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fld %st(2) // du | du*d_sdivzstepu | dv*d_sdivzstepv | du | dv
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fmuls C(d_tdivzstepu) // du*d_tdivzstepu | du*d_sdivzstepu |
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// dv*d_sdivzstepv | du | dv
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fxch %st(1) // du*d_sdivzstepu | du*d_tdivzstepu |
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// dv*d_sdivzstepv | du | dv
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faddp %st(0),%st(2) // du*d_tdivzstepu |
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// du*d_sdivzstepu + dv*d_sdivzstepv | du | dv
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fxch %st(1) // du*d_sdivzstepu + dv*d_sdivzstepv |
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// du*d_tdivzstepu | du | dv
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fld %st(3) // dv | du*d_sdivzstepu + dv*d_sdivzstepv |
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// du*d_tdivzstepu | du | dv
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fmuls C(d_tdivzstepv) // dv*d_tdivzstepv |
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// du*d_sdivzstepu + dv*d_sdivzstepv |
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// du*d_tdivzstepu | du | dv
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fxch %st(1) // du*d_sdivzstepu + dv*d_sdivzstepv |
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// dv*d_tdivzstepv | du*d_tdivzstepu | du | dv
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fadds C(d_sdivzorigin) // sdivz = d_sdivzorigin + dv*d_sdivzstepv +
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// du*d_sdivzstepu; stays in %st(2) at end
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fxch %st(4) // dv | dv*d_tdivzstepv | du*d_tdivzstepu | du |
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// s/z
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fmuls C(d_zistepv) // dv*d_zistepv | dv*d_tdivzstepv |
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// du*d_tdivzstepu | du | s/z
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fxch %st(1) // dv*d_tdivzstepv | dv*d_zistepv |
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// du*d_tdivzstepu | du | s/z
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faddp %st(0),%st(2) // dv*d_zistepv |
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// dv*d_tdivzstepv + du*d_tdivzstepu | du | s/z
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fxch %st(2) // du | dv*d_tdivzstepv + du*d_tdivzstepu |
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// dv*d_zistepv | s/z
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fmuls C(d_zistepu) // du*d_zistepu |
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// dv*d_tdivzstepv + du*d_tdivzstepu |
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// dv*d_zistepv | s/z
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fxch %st(1) // dv*d_tdivzstepv + du*d_tdivzstepu |
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// du*d_zistepu | dv*d_zistepv | s/z
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fadds C(d_tdivzorigin) // tdivz = d_tdivzorigin + dv*d_tdivzstepv +
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// du*d_tdivzstepu; stays in %st(1) at end
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fxch %st(2) // dv*d_zistepv | du*d_zistepu | t/z | s/z
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faddp %st(0),%st(1) // dv*d_zistepv + du*d_zistepu | t/z | s/z
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flds fp_64k // fp_64k | dv*d_zistepv + du*d_zistepu | t/z | s/z
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fxch %st(1) // dv*d_zistepv + du*d_zistepu | fp_64k | t/z | s/z
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fadds C(d_ziorigin) // zi = d_ziorigin + dv*d_zistepv +
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// du*d_zistepu; stays in %st(0) at end
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// 1/z | fp_64k | t/z | s/z
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//
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// calculate and clamp s & t
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//
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fdivr %st(0),%st(1) // 1/z | z*64k | t/z | s/z
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//
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// point %edi to the first pixel in the span
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//
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movl C(d_viewbuffer),%ecx
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movl espan_t_v(%ebx),%eax
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movl %ebx,pspantemp // preserve spans pointer
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movl C(tadjust),%edx
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movl C(sadjust),%esi
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movl C(d_scantable)(,%eax,4),%edi // v * screenwidth
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addl %ecx,%edi
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movl espan_t_u(%ebx),%ecx
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addl %ecx,%edi // pdest = &pdestspan[scans->u];
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movl espan_t_count(%ebx),%ecx
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//
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// now start the FDIV for the end of the span
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//
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cmpl $8,%ecx
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ja LSetupNotLast1
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decl %ecx
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jz LCleanup1 // if only one pixel, no need to start an FDIV
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movl %ecx,spancountminus1
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// finish up the s and t calcs
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fxch %st(1) // z*64k | 1/z | t/z | s/z
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fld %st(0) // z*64k | z*64k | 1/z | t/z | s/z
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fmul %st(4),%st(0) // s | z*64k | 1/z | t/z | s/z
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fxch %st(1) // z*64k | s | 1/z | t/z | s/z
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fmul %st(3),%st(0) // t | s | 1/z | t/z | s/z
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fxch %st(1) // s | t | 1/z | t/z | s/z
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fistpl s // 1/z | t | t/z | s/z
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fistpl t // 1/z | t/z | s/z
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fildl spancountminus1
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flds C(d_tdivzstepu) // C(d_tdivzstepu) | spancountminus1
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flds C(d_zistepu) // C(d_zistepu) | C(d_tdivzstepu) | spancountminus1
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fmul %st(2),%st(0) // C(d_zistepu)*scm1 | C(d_tdivzstepu) | scm1
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fxch %st(1) // C(d_tdivzstepu) | C(d_zistepu)*scm1 | scm1
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fmul %st(2),%st(0) // C(d_tdivzstepu)*scm1 | C(d_zistepu)*scm1 | scm1
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fxch %st(2) // scm1 | C(d_zistepu)*scm1 | C(d_tdivzstepu)*scm1
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fmuls C(d_sdivzstepu) // C(d_sdivzstepu)*scm1 | C(d_zistepu)*scm1 |
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// C(d_tdivzstepu)*scm1
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fxch %st(1) // C(d_zistepu)*scm1 | C(d_sdivzstepu)*scm1 |
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// C(d_tdivzstepu)*scm1
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faddp %st(0),%st(3) // C(d_sdivzstepu)*scm1 | C(d_tdivzstepu)*scm1
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fxch %st(1) // C(d_tdivzstepu)*scm1 | C(d_sdivzstepu)*scm1
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faddp %st(0),%st(3) // C(d_sdivzstepu)*scm1
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faddp %st(0),%st(3)
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flds fp_64k
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fdiv %st(1),%st(0) // this is what we've gone to all this trouble to
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// overlap
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jmp LFDIVInFlight1
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LCleanup1:
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// finish up the s and t calcs
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fxch %st(1) // z*64k | 1/z | t/z | s/z
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fld %st(0) // z*64k | z*64k | 1/z | t/z | s/z
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fmul %st(4),%st(0) // s | z*64k | 1/z | t/z | s/z
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fxch %st(1) // z*64k | s | 1/z | t/z | s/z
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fmul %st(3),%st(0) // t | s | 1/z | t/z | s/z
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fxch %st(1) // s | t | 1/z | t/z | s/z
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fistpl s // 1/z | t | t/z | s/z
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fistpl t // 1/z | t/z | s/z
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jmp LFDIVInFlight1
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.align 4
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LSetupNotLast1:
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// finish up the s and t calcs
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fxch %st(1) // z*64k | 1/z | t/z | s/z
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fld %st(0) // z*64k | z*64k | 1/z | t/z | s/z
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fmul %st(4),%st(0) // s | z*64k | 1/z | t/z | s/z
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fxch %st(1) // z*64k | s | 1/z | t/z | s/z
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fmul %st(3),%st(0) // t | s | 1/z | t/z | s/z
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fxch %st(1) // s | t | 1/z | t/z | s/z
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fistpl s // 1/z | t | t/z | s/z
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fistpl t // 1/z | t/z | s/z
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fadds zi8stepu
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fxch %st(2)
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fadds sdivz8stepu
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fxch %st(2)
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flds tdivz8stepu
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faddp %st(0),%st(2)
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flds fp_64k
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fdiv %st(1),%st(0) // z = 1/1/z
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// this is what we've gone to all this trouble to
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// overlap
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LFDIVInFlight1:
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addl s,%esi
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addl t,%edx
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movl C(bbextents),%ebx
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movl C(bbextentt),%ebp
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cmpl %ebx,%esi
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ja LClampHighOrLow0
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LClampReentry0:
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movl %esi,s
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movl pbase,%ebx
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shll $16,%esi
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cmpl %ebp,%edx
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movl %esi,sfracf
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ja LClampHighOrLow1
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LClampReentry1:
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movl %edx,t
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movl s,%esi // sfrac = scans->sfrac;
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shll $16,%edx
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movl t,%eax // tfrac = scans->tfrac;
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sarl $16,%esi
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movl %edx,tfracf
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//
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// calculate the texture starting address
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//
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sarl $16,%eax
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movl C(cachewidth),%edx
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imull %edx,%eax // (tfrac >> 16) * cachewidth
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addl %ebx,%esi
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addl %eax,%esi // psource = pbase + (sfrac >> 16) +
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// ((tfrac >> 16) * cachewidth);
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//
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// determine whether last span or not
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//
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cmpl $8,%ecx
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jna LLastSegment
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//
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// not the last segment; do full 8-wide segment
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//
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LNotLastSegment:
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//
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// advance s/z, t/z, and 1/z, and calculate s & t at end of span and steps to
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// get there
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//
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// pick up after the FDIV that was left in flight previously
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fld %st(0) // duplicate it
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fmul %st(4),%st(0) // s = s/z * z
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fxch %st(1)
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fmul %st(3),%st(0) // t = t/z * z
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fxch %st(1)
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fistpl snext
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fistpl tnext
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movl snext,%eax
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movl tnext,%edx
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movb (%esi),%bl // get first source texel
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subl $8,%ecx // count off this segments' pixels
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movl C(sadjust),%ebp
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movl %ecx,counttemp // remember count of remaining pixels
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movl C(tadjust),%ecx
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movb %bl,(%edi) // store first dest pixel
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addl %eax,%ebp
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addl %edx,%ecx
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movl C(bbextents),%eax
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movl C(bbextentt),%edx
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cmpl $2048,%ebp
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jl LClampLow2
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cmpl %eax,%ebp
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ja LClampHigh2
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LClampReentry2:
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cmpl $2048,%ecx
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jl LClampLow3
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cmpl %edx,%ecx
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ja LClampHigh3
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LClampReentry3:
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movl %ebp,snext
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movl %ecx,tnext
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subl s,%ebp
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subl t,%ecx
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//
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// set up advancetable
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//
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movl %ecx,%eax
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movl %ebp,%edx
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sarl $19,%eax // tstep >>= 16;
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jz LZero
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sarl $19,%edx // sstep >>= 16;
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movl C(cachewidth),%ebx
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imull %ebx,%eax
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jmp LSetUp1
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LZero:
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sarl $19,%edx // sstep >>= 16;
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movl C(cachewidth),%ebx
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LSetUp1:
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addl %edx,%eax // add in sstep
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// (tstep >> 16) * cachewidth + (sstep >> 16);
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movl tfracf,%edx
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movl %eax,advancetable+4 // advance base in t
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addl %ebx,%eax // ((tstep >> 16) + 1) * cachewidth +
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// (sstep >> 16);
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shll $13,%ebp // left-justify sstep fractional part
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movl sfracf,%ebx
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shll $13,%ecx // left-justify tstep fractional part
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movl %eax,advancetable // advance extra in t
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movl %ecx,tstep
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addl %ecx,%edx // advance tfrac fractional part by tstep frac
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sbbl %ecx,%ecx // turn tstep carry into -1 (0 if none)
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addl %ebp,%ebx // advance sfrac fractional part by sstep frac
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adcl advancetable+4(,%ecx,4),%esi // point to next source texel
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addl tstep,%edx
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sbbl %ecx,%ecx
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movb (%esi),%al
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addl %ebp,%ebx
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movb %al,1(%edi)
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adcl advancetable+4(,%ecx,4),%esi
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addl tstep,%edx
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sbbl %ecx,%ecx
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addl %ebp,%ebx
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movb (%esi),%al
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adcl advancetable+4(,%ecx,4),%esi
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addl tstep,%edx
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sbbl %ecx,%ecx
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movb %al,2(%edi)
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addl %ebp,%ebx
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movb (%esi),%al
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adcl advancetable+4(,%ecx,4),%esi
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addl tstep,%edx
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sbbl %ecx,%ecx
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movb %al,3(%edi)
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addl %ebp,%ebx
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movb (%esi),%al
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adcl advancetable+4(,%ecx,4),%esi
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//
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// start FDIV for end of next segment in flight, so it can overlap
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//
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movl counttemp,%ecx
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cmpl $8,%ecx // more than one segment after this?
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ja LSetupNotLast2 // yes
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decl %ecx
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jz LFDIVInFlight2 // if only one pixel, no need to start an FDIV
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movl %ecx,spancountminus1
|
|
fildl spancountminus1
|
|
|
|
flds C(d_zistepu) // C(d_zistepu) | spancountminus1
|
|
fmul %st(1),%st(0) // C(d_zistepu)*scm1 | scm1
|
|
flds C(d_tdivzstepu) // C(d_tdivzstepu) | C(d_zistepu)*scm1 | scm1
|
|
fmul %st(2),%st(0) // C(d_tdivzstepu)*scm1 | C(d_zistepu)*scm1 | scm1
|
|
fxch %st(1) // C(d_zistepu)*scm1 | C(d_tdivzstepu)*scm1 | scm1
|
|
faddp %st(0),%st(3) // C(d_tdivzstepu)*scm1 | scm1
|
|
fxch %st(1) // scm1 | C(d_tdivzstepu)*scm1
|
|
fmuls C(d_sdivzstepu) // C(d_sdivzstepu)*scm1 | C(d_tdivzstepu)*scm1
|
|
fxch %st(1) // C(d_tdivzstepu)*scm1 | C(d_sdivzstepu)*scm1
|
|
faddp %st(0),%st(3) // C(d_sdivzstepu)*scm1
|
|
flds fp_64k // 64k | C(d_sdivzstepu)*scm1
|
|
fxch %st(1) // C(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:
|
|
movl %ecx,counttemp
|
|
|
|
addl tstep,%edx
|
|
sbbl %ecx,%ecx
|
|
movb %al,4(%edi)
|
|
addl %ebp,%ebx
|
|
movb (%esi),%al
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
|
|
addl tstep,%edx
|
|
sbbl %ecx,%ecx
|
|
movb %al,5(%edi)
|
|
addl %ebp,%ebx
|
|
movb (%esi),%al
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
|
|
addl tstep,%edx
|
|
sbbl %ecx,%ecx
|
|
movb %al,6(%edi)
|
|
addl %ebp,%ebx
|
|
movb (%esi),%al
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
|
|
addl $8,%edi
|
|
movl %edx,tfracf
|
|
movl snext,%edx
|
|
movl %ebx,sfracf
|
|
movl tnext,%ebx
|
|
movl %edx,s
|
|
movl %ebx,t
|
|
|
|
movl counttemp,%ecx // retrieve count
|
|
|
|
//
|
|
// determine whether last span or not
|
|
//
|
|
cmpl $8,%ecx // are there multiple segments remaining?
|
|
movb %al,-1(%edi)
|
|
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
|
|
|
|
movb (%esi),%al // load first texel in segment
|
|
movl C(tadjust),%ebx
|
|
movb %al,(%edi) // store first pixel in segment
|
|
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 entryvec_table(,%ecx,4),%ebx
|
|
movl %edx,%eax
|
|
movl %ebx,jumptemp // entry point into code for RET later
|
|
movl %ebp,%ecx
|
|
sarl $16,%edx // tstep >>= 16;
|
|
movl C(cachewidth),%ebx
|
|
sarl $16,%ecx // sstep >>= 16;
|
|
imull %ebx,%edx
|
|
|
|
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 %ecx,%edx
|
|
addl %eax,%edx
|
|
sbbl %ecx,%ecx
|
|
addl %ebp,%ebx
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
|
|
jmp *jumptemp // jump to the number-of-pixels handler
|
|
|
|
//----------------------------------------
|
|
|
|
LNoSteps:
|
|
movb (%esi),%al // load first texel in segment
|
|
subl $7,%edi // adjust for hardwired offset
|
|
jmp LEndSpan
|
|
|
|
|
|
LOnlyOneStep:
|
|
subl s,%eax
|
|
subl t,%ebx
|
|
movl %eax,%ebp
|
|
movl %ebx,%edx
|
|
jmp LSetEntryvec
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Entry2_8
|
|
Entry2_8:
|
|
subl $6,%edi // adjust for hardwired offsets
|
|
movb (%esi),%al
|
|
jmp LLEntry2_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Entry3_8
|
|
Entry3_8:
|
|
subl $5,%edi // adjust for hardwired offsets
|
|
addl %eax,%edx
|
|
movb (%esi),%al
|
|
sbbl %ecx,%ecx
|
|
addl %ebp,%ebx
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
jmp LLEntry3_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Entry4_8
|
|
Entry4_8:
|
|
subl $4,%edi // adjust for hardwired offsets
|
|
addl %eax,%edx
|
|
movb (%esi),%al
|
|
sbbl %ecx,%ecx
|
|
addl %ebp,%ebx
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
addl tstep,%edx
|
|
jmp LLEntry4_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Entry5_8
|
|
Entry5_8:
|
|
subl $3,%edi // adjust for hardwired offsets
|
|
addl %eax,%edx
|
|
movb (%esi),%al
|
|
sbbl %ecx,%ecx
|
|
addl %ebp,%ebx
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
addl tstep,%edx
|
|
jmp LLEntry5_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Entry6_8
|
|
Entry6_8:
|
|
subl $2,%edi // adjust for hardwired offsets
|
|
addl %eax,%edx
|
|
movb (%esi),%al
|
|
sbbl %ecx,%ecx
|
|
addl %ebp,%ebx
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
addl tstep,%edx
|
|
jmp LLEntry6_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Entry7_8
|
|
Entry7_8:
|
|
decl %edi // adjust for hardwired offsets
|
|
addl %eax,%edx
|
|
movb (%esi),%al
|
|
sbbl %ecx,%ecx
|
|
addl %ebp,%ebx
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
addl tstep,%edx
|
|
jmp LLEntry7_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Entry8_8
|
|
Entry8_8:
|
|
addl %eax,%edx
|
|
movb (%esi),%al
|
|
sbbl %ecx,%ecx
|
|
addl %ebp,%ebx
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
|
|
addl tstep,%edx
|
|
sbbl %ecx,%ecx
|
|
movb %al,1(%edi)
|
|
addl %ebp,%ebx
|
|
movb (%esi),%al
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
addl tstep,%edx
|
|
LLEntry7_8:
|
|
sbbl %ecx,%ecx
|
|
movb %al,2(%edi)
|
|
addl %ebp,%ebx
|
|
movb (%esi),%al
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
addl tstep,%edx
|
|
LLEntry6_8:
|
|
sbbl %ecx,%ecx
|
|
movb %al,3(%edi)
|
|
addl %ebp,%ebx
|
|
movb (%esi),%al
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
addl tstep,%edx
|
|
LLEntry5_8:
|
|
sbbl %ecx,%ecx
|
|
movb %al,4(%edi)
|
|
addl %ebp,%ebx
|
|
movb (%esi),%al
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
addl tstep,%edx
|
|
LLEntry4_8:
|
|
sbbl %ecx,%ecx
|
|
movb %al,5(%edi)
|
|
addl %ebp,%ebx
|
|
movb (%esi),%al
|
|
adcl advancetable+4(,%ecx,4),%esi
|
|
LLEntry3_8:
|
|
movb %al,6(%edi)
|
|
movb (%esi),%al
|
|
LLEntry2_8:
|
|
|
|
LEndSpan:
|
|
|
|
//
|
|
// clear s/z, t/z, 1/z from FP stack
|
|
//
|
|
fstp %st(0)
|
|
fstp %st(0)
|
|
fstp %st(0)
|
|
|
|
movl pspantemp,%ebx // restore spans pointer
|
|
movl espan_t_pnext(%ebx),%ebx // point to next span
|
|
testl %ebx,%ebx // any more spans?
|
|
movb %al,7(%edi)
|
|
jnz LSpanLoop // more spans
|
|
|
|
popl %ebx // restore register variables
|
|
popl %esi
|
|
popl %edi
|
|
popl %ebp // restore the caller's stack frame
|
|
ret
|
|
|
|
//----------------------------------------------------------------------
|
|
// 8-bpp horizontal span z drawing codefor polygons, with no transparency.
|
|
//
|
|
// Assumes there is at least one span in pzspans, and that every span
|
|
// contains at least one pixel
|
|
//----------------------------------------------------------------------
|
|
|
|
.text
|
|
|
|
// z-clamp on a non-negative gradient span
|
|
LClamp:
|
|
movl $0x40000000,%edx
|
|
xorl %ebx,%ebx
|
|
fstp %st(0)
|
|
jmp LZDraw
|
|
|
|
// z-clamp on a negative gradient span
|
|
LClampNeg:
|
|
movl $0x40000000,%edx
|
|
xorl %ebx,%ebx
|
|
fstp %st(0)
|
|
jmp LZDrawNeg
|
|
|
|
|
|
#define pzspans 4+16
|
|
|
|
.globl C(D_DrawZSpans)
|
|
C(D_DrawZSpans):
|
|
pushl %ebp // preserve caller's stack frame
|
|
pushl %edi
|
|
pushl %esi // preserve register variables
|
|
pushl %ebx
|
|
|
|
flds C(d_zistepu)
|
|
movl C(d_zistepu),%eax
|
|
movl pzspans(%esp),%esi
|
|
testl %eax,%eax
|
|
jz LFNegSpan
|
|
|
|
fmuls Float2ToThe31nd
|
|
fistpl izistep // note: we are relying on FP exceptions being turned
|
|
// off here to avoid range problems
|
|
movl izistep,%ebx // remains loaded for all spans
|
|
|
|
LFSpanLoop:
|
|
// set up the initial 1/z value
|
|
fildl espan_t_v(%esi)
|
|
fildl espan_t_u(%esi)
|
|
movl espan_t_v(%esi),%ecx
|
|
movl C(d_pzbuffer),%edi
|
|
fmuls C(d_zistepu)
|
|
fxch %st(1)
|
|
fmuls C(d_zistepv)
|
|
fxch %st(1)
|
|
fadds C(d_ziorigin)
|
|
imull C(d_zrowbytes),%ecx
|
|
faddp %st(0),%st(1)
|
|
|
|
// clamp if z is nearer than 2 (1/z > 0.5)
|
|
fcoms float_point5
|
|
addl %ecx,%edi
|
|
movl espan_t_u(%esi),%edx
|
|
addl %edx,%edx // word count
|
|
movl espan_t_count(%esi),%ecx
|
|
addl %edx,%edi // pdest = &pdestspan[scans->u];
|
|
pushl %esi // preserve spans pointer
|
|
fnstsw %ax
|
|
testb $0x45,%ah
|
|
jz LClamp
|
|
|
|
fmuls Float2ToThe31nd
|
|
fistpl izi // note: we are relying on FP exceptions being turned
|
|
// off here to avoid problems when the span is closer
|
|
// than 1/(2**31)
|
|
movl izi,%edx
|
|
|
|
// at this point:
|
|
// %ebx = izistep
|
|
// %ecx = count
|
|
// %edx = izi
|
|
// %edi = pdest
|
|
|
|
LZDraw:
|
|
|
|
// do a single pixel up front, if necessary to dword align the destination
|
|
testl $2,%edi
|
|
jz LFMiddle
|
|
movl %edx,%eax
|
|
addl %ebx,%edx
|
|
shrl $16,%eax
|
|
decl %ecx
|
|
movw %ax,(%edi)
|
|
addl $2,%edi
|
|
|
|
// do middle a pair of aligned dwords at a time
|
|
LFMiddle:
|
|
pushl %ecx
|
|
shrl $1,%ecx // count / 2
|
|
jz LFLast // no aligned dwords to do
|
|
shrl $1,%ecx // (count / 2) / 2
|
|
jnc LFMiddleLoop // even number of aligned dwords to do
|
|
|
|
movl %edx,%eax
|
|
addl %ebx,%edx
|
|
shrl $16,%eax
|
|
movl %edx,%esi
|
|
addl %ebx,%edx
|
|
andl $0xFFFF0000,%esi
|
|
orl %esi,%eax
|
|
movl %eax,(%edi)
|
|
addl $4,%edi
|
|
andl %ecx,%ecx
|
|
jz LFLast
|
|
|
|
LFMiddleLoop:
|
|
movl %edx,%eax
|
|
addl %ebx,%edx
|
|
shrl $16,%eax
|
|
movl %edx,%esi
|
|
addl %ebx,%edx
|
|
andl $0xFFFF0000,%esi
|
|
orl %esi,%eax
|
|
movl %edx,%ebp
|
|
movl %eax,(%edi)
|
|
addl %ebx,%edx
|
|
shrl $16,%ebp
|
|
movl %edx,%esi
|
|
addl %ebx,%edx
|
|
andl $0xFFFF0000,%esi
|
|
orl %esi,%ebp
|
|
movl %ebp,4(%edi) // FIXME: eliminate register contention
|
|
addl $8,%edi
|
|
|
|
decl %ecx
|
|
jnz LFMiddleLoop
|
|
|
|
LFLast:
|
|
popl %ecx // retrieve count
|
|
popl %esi // retrieve span pointer
|
|
|
|
// do the last, unaligned pixel, if there is one
|
|
andl $1,%ecx // is there an odd pixel left to do?
|
|
jz LFSpanDone // no
|
|
shrl $16,%edx
|
|
movw %dx,(%edi) // do the final pixel's z
|
|
|
|
LFSpanDone:
|
|
movl espan_t_pnext(%esi),%esi
|
|
testl %esi,%esi
|
|
jnz LFSpanLoop
|
|
|
|
jmp LFDone
|
|
|
|
LFNegSpan:
|
|
fmuls FloatMinus2ToThe31nd
|
|
fistpl izistep // note: we are relying on FP exceptions being turned
|
|
// off here to avoid range problems
|
|
movl izistep,%ebx // remains loaded for all spans
|
|
|
|
LFNegSpanLoop:
|
|
// set up the initial 1/z value
|
|
fildl espan_t_v(%esi)
|
|
fildl espan_t_u(%esi)
|
|
movl espan_t_v(%esi),%ecx
|
|
movl C(d_pzbuffer),%edi
|
|
fmuls C(d_zistepu)
|
|
fxch %st(1)
|
|
fmuls C(d_zistepv)
|
|
fxch %st(1)
|
|
fadds C(d_ziorigin)
|
|
imull C(d_zrowbytes),%ecx
|
|
faddp %st(0),%st(1)
|
|
|
|
// clamp if z is nearer than 2 (1/z > 0.5)
|
|
fcoms float_point5
|
|
addl %ecx,%edi
|
|
movl espan_t_u(%esi),%edx
|
|
addl %edx,%edx // word count
|
|
movl espan_t_count(%esi),%ecx
|
|
addl %edx,%edi // pdest = &pdestspan[scans->u];
|
|
pushl %esi // preserve spans pointer
|
|
fnstsw %ax
|
|
testb $0x45,%ah
|
|
jz LClampNeg
|
|
|
|
fmuls Float2ToThe31nd
|
|
fistpl izi // note: we are relying on FP exceptions being turned
|
|
// off here to avoid problems when the span is closer
|
|
// than 1/(2**31)
|
|
movl izi,%edx
|
|
|
|
// at this point:
|
|
// %ebx = izistep
|
|
// %ecx = count
|
|
// %edx = izi
|
|
// %edi = pdest
|
|
|
|
LZDrawNeg:
|
|
|
|
// do a single pixel up front, if necessary to dword align the destination
|
|
testl $2,%edi
|
|
jz LFNegMiddle
|
|
movl %edx,%eax
|
|
subl %ebx,%edx
|
|
shrl $16,%eax
|
|
decl %ecx
|
|
movw %ax,(%edi)
|
|
addl $2,%edi
|
|
|
|
// do middle a pair of aligned dwords at a time
|
|
LFNegMiddle:
|
|
pushl %ecx
|
|
shrl $1,%ecx // count / 2
|
|
jz LFNegLast // no aligned dwords to do
|
|
shrl $1,%ecx // (count / 2) / 2
|
|
jnc LFNegMiddleLoop // even number of aligned dwords to do
|
|
|
|
movl %edx,%eax
|
|
subl %ebx,%edx
|
|
shrl $16,%eax
|
|
movl %edx,%esi
|
|
subl %ebx,%edx
|
|
andl $0xFFFF0000,%esi
|
|
orl %esi,%eax
|
|
movl %eax,(%edi)
|
|
addl $4,%edi
|
|
andl %ecx,%ecx
|
|
jz LFNegLast
|
|
|
|
LFNegMiddleLoop:
|
|
movl %edx,%eax
|
|
subl %ebx,%edx
|
|
shrl $16,%eax
|
|
movl %edx,%esi
|
|
subl %ebx,%edx
|
|
andl $0xFFFF0000,%esi
|
|
orl %esi,%eax
|
|
movl %edx,%ebp
|
|
movl %eax,(%edi)
|
|
subl %ebx,%edx
|
|
shrl $16,%ebp
|
|
movl %edx,%esi
|
|
subl %ebx,%edx
|
|
andl $0xFFFF0000,%esi
|
|
orl %esi,%ebp
|
|
movl %ebp,4(%edi) // FIXME: eliminate register contention
|
|
addl $8,%edi
|
|
|
|
decl %ecx
|
|
jnz LFNegMiddleLoop
|
|
|
|
LFNegLast:
|
|
popl %ecx // retrieve count
|
|
popl %esi // retrieve span pointer
|
|
|
|
// do the last, unaligned pixel, if there is one
|
|
andl $1,%ecx // is there an odd pixel left to do?
|
|
jz LFNegSpanDone // no
|
|
shrl $16,%edx
|
|
movw %dx,(%edi) // do the final pixel's z
|
|
|
|
LFNegSpanDone:
|
|
movl espan_t_pnext(%esi),%esi
|
|
testl %esi,%esi
|
|
jnz LFNegSpanLoop
|
|
|
|
LFDone:
|
|
popl %ebx // restore register variables
|
|
popl %esi
|
|
popl %edi
|
|
popl %ebp // restore the caller's stack frame
|
|
ret
|
|
|
|
#endif // id386
|