ref: 26e253158ac93bbc14cc381780f9b37ea7858bd1
dir: /u/r_edgea.s/
//
// r_edgea.s
// x86 assembly-language edge-processing code.
//
#include "asm_i386.h"
#include "quakeasm.h"
#include "asm_draw.h"
#ifdef id386
.data
Ltemp: .long 0
float_1_div_0100000h: .long 0x35800000 // 1.0/(float)0x100000
float_point_999: .single 0.999
float_1_point_001: .single 1.001
.text
//--------------------------------------------------------------------
#define edgestoadd 4+8 // note odd stack offsets because of interleaving
#define edgelist 8+12 // with pushes
.globl C(R_EdgeCodeStart)
C(R_EdgeCodeStart):
.globl C(R_InsertNewEdges)
C(R_InsertNewEdges):
pushl %edi
pushl %esi // preserve register variables
movl edgestoadd(%esp),%edx
pushl %ebx
movl edgelist(%esp),%ecx
LDoNextEdge:
movl et_u(%edx),%eax
movl %edx,%edi
LContinueSearch:
movl et_u(%ecx),%ebx
movl et_next(%ecx),%esi
cmpl %ebx,%eax
jle LAddedge
movl et_u(%esi),%ebx
movl et_next(%esi),%ecx
cmpl %ebx,%eax
jle LAddedge2
movl et_u(%ecx),%ebx
movl et_next(%ecx),%esi
cmpl %ebx,%eax
jle LAddedge
movl et_u(%esi),%ebx
movl et_next(%esi),%ecx
cmpl %ebx,%eax
jg LContinueSearch
LAddedge2:
movl et_next(%edx),%edx
movl et_prev(%esi),%ebx
movl %esi,et_next(%edi)
movl %ebx,et_prev(%edi)
movl %edi,et_next(%ebx)
movl %edi,et_prev(%esi)
movl %esi,%ecx
cmpl $0,%edx
jnz LDoNextEdge
jmp LDone
.align 4
LAddedge:
movl et_next(%edx),%edx
movl et_prev(%ecx),%ebx
movl %ecx,et_next(%edi)
movl %ebx,et_prev(%edi)
movl %edi,et_next(%ebx)
movl %edi,et_prev(%ecx)
cmpl $0,%edx
jnz LDoNextEdge
LDone:
popl %ebx // restore register variables
popl %esi
popl %edi
ret
//--------------------------------------------------------------------
#define predge 4+4
.globl C(R_RemoveEdges)
C(R_RemoveEdges):
pushl %ebx
movl predge(%esp),%eax
Lre_loop:
movl et_next(%eax),%ecx
movl et_nextremove(%eax),%ebx
movl et_prev(%eax),%edx
testl %ebx,%ebx
movl %edx,et_prev(%ecx)
jz Lre_done
movl %ecx,et_next(%edx)
movl et_next(%ebx),%ecx
movl et_prev(%ebx),%edx
movl et_nextremove(%ebx),%eax
movl %edx,et_prev(%ecx)
testl %eax,%eax
movl %ecx,et_next(%edx)
jnz Lre_loop
popl %ebx
ret
Lre_done:
movl %ecx,et_next(%edx)
popl %ebx
ret
//--------------------------------------------------------------------
#define pedgelist 4+4 // note odd stack offset because of interleaving
// with pushes
.globl C(R_StepActiveU)
C(R_StepActiveU):
pushl %edi
movl pedgelist(%esp),%edx
pushl %esi // preserve register variables
pushl %ebx
movl et_prev(%edx),%esi
LNewEdge:
movl et_u(%esi),%edi
LNextEdge:
movl et_u(%edx),%eax
movl et_u_step(%edx),%ebx
addl %ebx,%eax
movl et_next(%edx),%esi
movl %eax,et_u(%edx)
cmpl %edi,%eax
jl LPushBack
movl et_u(%esi),%edi
movl et_u_step(%esi),%ebx
addl %ebx,%edi
movl et_next(%esi),%edx
movl %edi,et_u(%esi)
cmpl %eax,%edi
jl LPushBack2
movl et_u(%edx),%eax
movl et_u_step(%edx),%ebx
addl %ebx,%eax
movl et_next(%edx),%esi
movl %eax,et_u(%edx)
cmpl %edi,%eax
jl LPushBack
movl et_u(%esi),%edi
movl et_u_step(%esi),%ebx
addl %ebx,%edi
movl et_next(%esi),%edx
movl %edi,et_u(%esi)
cmpl %eax,%edi
jnl LNextEdge
LPushBack2:
movl %edx,%ebx
movl %edi,%eax
movl %esi,%edx
movl %ebx,%esi
LPushBack:
// push it back to keep it sorted
movl et_prev(%edx),%ecx
movl et_next(%edx),%ebx
// done if the -1 in edge_aftertail triggered this
cmpl $(C(edge_aftertail)),%edx
jz LUDone
// pull the edge out of the edge list
movl et_prev(%ecx),%edi
movl %ecx,et_prev(%esi)
movl %ebx,et_next(%ecx)
// find out where the edge goes in the edge list
LPushBackLoop:
movl et_prev(%edi),%ecx
movl et_u(%edi),%ebx
cmpl %ebx,%eax
jnl LPushBackFound
movl et_prev(%ecx),%edi
movl et_u(%ecx),%ebx
cmpl %ebx,%eax
jl LPushBackLoop
movl %ecx,%edi
// put the edge back into the edge list
LPushBackFound:
movl et_next(%edi),%ebx
movl %edi,et_prev(%edx)
movl %ebx,et_next(%edx)
movl %edx,et_next(%edi)
movl %edx,et_prev(%ebx)
movl %esi,%edx
movl et_prev(%esi),%esi
cmpl $(C(edge_tail)),%edx
jnz LNewEdge
LUDone:
popl %ebx // restore register variables
popl %esi
popl %edi
ret
//--------------------------------------------------------------------
#define surf 4 // note this is loaded before any pushes
.align 4
TrailingEdge:
movl st_spanstate(%esi),%eax // check for edge inversion
decl %eax
jnz LInverted
movl %eax,st_spanstate(%esi)
movl st_insubmodel(%esi),%ecx
movl 0x12345678,%edx // surfaces[1].st_next
LPatch0:
movl C(r_bmodelactive),%eax
subl %ecx,%eax
cmpl %esi,%edx
movl %eax,C(r_bmodelactive)
jnz LNoEmit // surface isn't on top, just remove
// emit a span (current top going away)
movl et_u(%ebx),%eax
shrl $20,%eax // iu = integral pixel u
movl st_last_u(%esi),%edx
movl st_next(%esi),%ecx
cmpl %edx,%eax
jle LNoEmit2 // iu <= surf->last_u, so nothing to emit
movl %eax,st_last_u(%ecx) // surf->next->last_u = iu;
subl %edx,%eax
movl %edx,espan_t_u(%ebp) // span->u = surf->last_u;
movl %eax,espan_t_count(%ebp) // span->count = iu - span->u;
movl C(current_iv),%eax
movl %eax,espan_t_v(%ebp) // span->v = current_iv;
movl st_spans(%esi),%eax
movl %eax,espan_t_pnext(%ebp) // span->pnext = surf->spans;
movl %ebp,st_spans(%esi) // surf->spans = span;
addl $(espan_t_size),%ebp
movl st_next(%esi),%edx // remove the surface from the surface
movl st_prev(%esi),%esi // stack
movl %edx,st_next(%esi)
movl %esi,st_prev(%edx)
ret
LNoEmit2:
movl %eax,st_last_u(%ecx) // surf->next->last_u = iu;
movl st_next(%esi),%edx // remove the surface from the surface
movl st_prev(%esi),%esi // stack
movl %edx,st_next(%esi)
movl %esi,st_prev(%edx)
ret
LNoEmit:
movl st_next(%esi),%edx // remove the surface from the surface
movl st_prev(%esi),%esi // stack
movl %edx,st_next(%esi)
movl %esi,st_prev(%edx)
ret
LInverted:
movl %eax,st_spanstate(%esi)
ret
//--------------------------------------------------------------------
// trailing edge only
Lgs_trailing:
pushl $Lgs_nextedge
jmp TrailingEdge
.globl C(R_GenerateSpans)
C(R_GenerateSpans):
pushl %ebp // preserve caller's stack frame
pushl %edi
pushl %esi // preserve register variables
pushl %ebx
// clear active surfaces to just the background surface
movl C(surfaces),%eax
movl C(edge_head_u_shift20),%edx
addl $(st_size),%eax
// %ebp = span_p throughout
movl C(span_p),%ebp
movl $0,C(r_bmodelactive)
movl %eax,st_next(%eax)
movl %eax,st_prev(%eax)
movl %edx,st_last_u(%eax)
movl C(edge_head)+et_next,%ebx // edge=edge_head.next
// generate spans
cmpl $(C(edge_tail)),%ebx // done if empty list
jz Lgs_lastspan
Lgs_edgeloop:
movl et_surfs(%ebx),%edi
movl C(surfaces),%eax
movl %edi,%esi
andl $0xFFFF0000,%edi
andl $0xFFFF,%esi
jz Lgs_leading // not a trailing edge
// it has a left surface, so a surface is going away for this span
shll $(SURF_T_SHIFT),%esi
addl %eax,%esi
testl %edi,%edi
jz Lgs_trailing
// both leading and trailing
call TrailingEdge
movl C(surfaces),%eax
// ---------------------------------------------------------------
// handle a leading edge
// ---------------------------------------------------------------
Lgs_leading:
shrl $16-SURF_T_SHIFT,%edi
movl C(surfaces),%eax
addl %eax,%edi
movl 0x12345678,%esi // surf2 = surfaces[1].next;
LPatch2:
movl st_spanstate(%edi),%edx
movl st_insubmodel(%edi),%eax
testl %eax,%eax
jnz Lbmodel_leading
// handle a leading non-bmodel edge
// don't start a span if this is an inverted span, with the end edge preceding
// the start edge (that is, we've already seen the end edge)
testl %edx,%edx
jnz Lxl_done
// if (surf->key < surf2->key)
// goto newtop;
incl %edx
movl st_key(%edi),%eax
movl %edx,st_spanstate(%edi)
movl st_key(%esi),%ecx
cmpl %ecx,%eax
jl Lnewtop
// main sorting loop to search through surface stack until insertion point
// found. Always terminates because background surface is sentinel
// do
// {
// surf2 = surf2->next;
// } while (surf->key >= surf2->key);
Lsortloopnb:
movl st_next(%esi),%esi
movl st_key(%esi),%ecx
cmpl %ecx,%eax
jge Lsortloopnb
jmp LInsertAndExit
// handle a leading bmodel edge
.align 4
Lbmodel_leading:
// don't start a span if this is an inverted span, with the end edge preceding
// the start edge (that is, we've already seen the end edge)
testl %edx,%edx
jnz Lxl_done
movl C(r_bmodelactive),%ecx
incl %edx
incl %ecx
movl %edx,st_spanstate(%edi)
movl %ecx,C(r_bmodelactive)
// if (surf->key < surf2->key)
// goto newtop;
movl st_key(%edi),%eax
movl st_key(%esi),%ecx
cmpl %ecx,%eax
jl Lnewtop
// if ((surf->key == surf2->key) && surf->insubmodel)
// {
jz Lzcheck_for_newtop
// main sorting loop to search through surface stack until insertion point
// found. Always terminates because background surface is sentinel
// do
// {
// surf2 = surf2->next;
// } while (surf->key > surf2->key);
Lsortloop:
movl st_next(%esi),%esi
movl st_key(%esi),%ecx
cmpl %ecx,%eax
jg Lsortloop
jne LInsertAndExit
// Do 1/z sorting to see if we've arrived in the right position
movl et_u(%ebx),%eax
subl $0xFFFFF,%eax
movl %eax,Ltemp
fildl Ltemp
fmuls float_1_div_0100000h // fu = (float)(edge->u - 0xFFFFF) *
// (1.0 / 0x100000);
fld %st(0) // fu | fu
fmuls st_d_zistepu(%edi) // fu*surf->d_zistepu | fu
flds C(fv) // fv | fu*surf->d_zistepu | fu
fmuls st_d_zistepv(%edi) // fv*surf->d_zistepv | fu*surf->d_zistepu | fu
fxch %st(1) // fu*surf->d_zistepu | fv*surf->d_zistepv | fu
fadds st_d_ziorigin(%edi) // fu*surf->d_zistepu + surf->d_ziorigin |
// fv*surf->d_zistepv | fu
flds st_d_zistepu(%esi) // surf2->d_zistepu |
// fu*surf->d_zistepu + surf->d_ziorigin |
// fv*surf->d_zistepv | fu
fmul %st(3),%st(0) // fu*surf2->d_zistepu |
// fu*surf->d_zistepu + surf->d_ziorigin |
// fv*surf->d_zistepv | fu
fxch %st(1) // fu*surf->d_zistepu + surf->d_ziorigin |
// fu*surf2->d_zistepu |
// fv*surf->d_zistepv | fu
faddp %st(0),%st(2) // fu*surf2->d_zistepu | newzi | fu
flds C(fv) // fv | fu*surf2->d_zistepu | newzi | fu
fmuls st_d_zistepv(%esi) // fv*surf2->d_zistepv |
// fu*surf2->d_zistepu | newzi | fu
fld %st(2) // newzi | fv*surf2->d_zistepv |
// fu*surf2->d_zistepu | newzi | fu
fmuls float_point_999 // newzibottom | fv*surf2->d_zistepv |
// fu*surf2->d_zistepu | newzi | fu
fxch %st(2) // fu*surf2->d_zistepu | fv*surf2->d_zistepv |
// newzibottom | newzi | fu
fadds st_d_ziorigin(%esi) // fu*surf2->d_zistepu + surf2->d_ziorigin |
// fv*surf2->d_zistepv | newzibottom | newzi |
// fu
faddp %st(0),%st(1) // testzi | newzibottom | newzi | fu
fxch %st(1) // newzibottom | testzi | newzi | fu
// if (newzibottom >= testzi)
// goto Lgotposition;
fcomp %st(1) // testzi | newzi | fu
fxch %st(1) // newzi | testzi | fu
fmuls float_1_point_001 // newzitop | testzi | fu
fxch %st(1) // testzi | newzitop | fu
fnstsw %ax
testb $0x01,%ah
jz Lgotposition_fpop3
// if (newzitop >= testzi)
// {
fcomp %st(1) // newzitop | fu
fnstsw %ax
testb $0x45,%ah
jz Lsortloop_fpop2
// if (surf->d_zistepu >= surf2->d_zistepu)
// goto newtop;
flds st_d_zistepu(%edi) // surf->d_zistepu | newzitop| fu
fcomps st_d_zistepu(%esi) // newzitop | fu
fnstsw %ax
testb $0x01,%ah
jz Lgotposition_fpop2
fstp %st(0) // clear the FPstack
fstp %st(0)
movl st_key(%edi),%eax
jmp Lsortloop
Lgotposition_fpop3:
fstp %st(0)
Lgotposition_fpop2:
fstp %st(0)
fstp %st(0)
jmp LInsertAndExit
// emit a span (obscures current top)
Lnewtop_fpop3:
fstp %st(0)
Lnewtop_fpop2:
fstp %st(0)
fstp %st(0)
movl st_key(%edi),%eax // reload the sorting key
Lnewtop:
movl et_u(%ebx),%eax
movl st_last_u(%esi),%edx
shrl $20,%eax // iu = integral pixel u
movl %eax,st_last_u(%edi) // surf->last_u = iu;
cmpl %edx,%eax
jle LInsertAndExit // iu <= surf->last_u, so nothing to emit
subl %edx,%eax
movl %edx,espan_t_u(%ebp) // span->u = surf->last_u;
movl %eax,espan_t_count(%ebp) // span->count = iu - span->u;
movl C(current_iv),%eax
movl %eax,espan_t_v(%ebp) // span->v = current_iv;
movl st_spans(%esi),%eax
movl %eax,espan_t_pnext(%ebp) // span->pnext = surf->spans;
movl %ebp,st_spans(%esi) // surf->spans = span;
addl $(espan_t_size),%ebp
LInsertAndExit:
// insert before surf2
movl %esi,st_next(%edi) // surf->next = surf2;
movl st_prev(%esi),%eax
movl %eax,st_prev(%edi) // surf->prev = surf2->prev;
movl %edi,st_prev(%esi) // surf2->prev = surf;
movl %edi,st_next(%eax) // surf2->prev->next = surf;
// ---------------------------------------------------------------
// leading edge done
// ---------------------------------------------------------------
// ---------------------------------------------------------------
// see if there are any more edges
// ---------------------------------------------------------------
Lgs_nextedge:
movl et_next(%ebx),%ebx
cmpl $(C(edge_tail)),%ebx
jnz Lgs_edgeloop
// clean up at the right edge
Lgs_lastspan:
// now that we've reached the right edge of the screen, we're done with any
// unfinished surfaces, so emit a span for whatever's on top
movl 0x12345678,%esi // surfaces[1].st_next
LPatch3:
movl C(edge_tail_u_shift20),%eax
xorl %ecx,%ecx
movl st_last_u(%esi),%edx
subl %edx,%eax
jle Lgs_resetspanstate
movl %edx,espan_t_u(%ebp)
movl %eax,espan_t_count(%ebp)
movl C(current_iv),%eax
movl %eax,espan_t_v(%ebp)
movl st_spans(%esi),%eax
movl %eax,espan_t_pnext(%ebp)
movl %ebp,st_spans(%esi)
addl $(espan_t_size),%ebp
// reset spanstate for all surfaces in the surface stack
Lgs_resetspanstate:
movl %ecx,st_spanstate(%esi)
movl st_next(%esi),%esi
cmpl $0x12345678,%esi // &surfaces[1]
LPatch4:
jnz Lgs_resetspanstate
// store the final span_p
movl %ebp,C(span_p)
popl %ebx // restore register variables
popl %esi
popl %edi
popl %ebp // restore the caller's stack frame
ret
// ---------------------------------------------------------------
// 1/z sorting for bmodels in the same leaf
// ---------------------------------------------------------------
.align 4
Lxl_done:
incl %edx
movl %edx,st_spanstate(%edi)
jmp Lgs_nextedge
.align 4
Lzcheck_for_newtop:
movl et_u(%ebx),%eax
subl $0xFFFFF,%eax
movl %eax,Ltemp
fildl Ltemp
fmuls float_1_div_0100000h // fu = (float)(edge->u - 0xFFFFF) *
// (1.0 / 0x100000);
fld %st(0) // fu | fu
fmuls st_d_zistepu(%edi) // fu*surf->d_zistepu | fu
flds C(fv) // fv | fu*surf->d_zistepu | fu
fmuls st_d_zistepv(%edi) // fv*surf->d_zistepv | fu*surf->d_zistepu | fu
fxch %st(1) // fu*surf->d_zistepu | fv*surf->d_zistepv | fu
fadds st_d_ziorigin(%edi) // fu*surf->d_zistepu + surf->d_ziorigin |
// fv*surf->d_zistepv | fu
flds st_d_zistepu(%esi) // surf2->d_zistepu |
// fu*surf->d_zistepu + surf->d_ziorigin |
// fv*surf->d_zistepv | fu
fmul %st(3),%st(0) // fu*surf2->d_zistepu |
// fu*surf->d_zistepu + surf->d_ziorigin |
// fv*surf->d_zistepv | fu
fxch %st(1) // fu*surf->d_zistepu + surf->d_ziorigin |
// fu*surf2->d_zistepu |
// fv*surf->d_zistepv | fu
faddp %st(0),%st(2) // fu*surf2->d_zistepu | newzi | fu
flds C(fv) // fv | fu*surf2->d_zistepu | newzi | fu
fmuls st_d_zistepv(%esi) // fv*surf2->d_zistepv |
// fu*surf2->d_zistepu | newzi | fu
fld %st(2) // newzi | fv*surf2->d_zistepv |
// fu*surf2->d_zistepu | newzi | fu
fmuls float_point_999 // newzibottom | fv*surf2->d_zistepv |
// fu*surf2->d_zistepu | newzi | fu
fxch %st(2) // fu*surf2->d_zistepu | fv*surf2->d_zistepv |
// newzibottom | newzi | fu
fadds st_d_ziorigin(%esi) // fu*surf2->d_zistepu + surf2->d_ziorigin |
// fv*surf2->d_zistepv | newzibottom | newzi |
// fu
faddp %st(0),%st(1) // testzi | newzibottom | newzi | fu
fxch %st(1) // newzibottom | testzi | newzi | fu
// if (newzibottom >= testzi)
// goto newtop;
fcomp %st(1) // testzi | newzi | fu
fxch %st(1) // newzi | testzi | fu
fmuls float_1_point_001 // newzitop | testzi | fu
fxch %st(1) // testzi | newzitop | fu
fnstsw %ax
testb $0x01,%ah
jz Lnewtop_fpop3
// if (newzitop >= testzi)
// {
fcomp %st(1) // newzitop | fu
fnstsw %ax
testb $0x45,%ah
jz Lsortloop_fpop2
// if (surf->d_zistepu >= surf2->d_zistepu)
// goto newtop;
flds st_d_zistepu(%edi) // surf->d_zistepu | newzitop | fu
fcomps st_d_zistepu(%esi) // newzitop | fu
fnstsw %ax
testb $0x01,%ah
jz Lnewtop_fpop2
Lsortloop_fpop2:
fstp %st(0) // clear the FP stack
fstp %st(0)
movl st_key(%edi),%eax
jmp Lsortloop
.globl C(R_EdgeCodeEnd)
C(R_EdgeCodeEnd):
//----------------------------------------------------------------------
// Surface array address code patching routine
//----------------------------------------------------------------------
.align 4
.globl C(R_SurfacePatch)
C(R_SurfacePatch):
movl C(surfaces),%eax
addl $(st_size),%eax
movl %eax,LPatch4-4
addl $(st_next),%eax
movl %eax,LPatch0-4
movl %eax,LPatch2-4
movl %eax,LPatch3-4
ret
#endif // id386