ref: a63d5778cb72c91bf1b14aaa4453a0239cc4a823
dir: /u/worlda.s/
//
// worlda.s
// x86 assembly-language server testing stuff
//
#define GLQUAKE 1 // don't include unneeded defs
#include "asm_i386.h"
#include "quakeasm.h"
#include "d_ifacea.h"
#ifdef id386
.data
Ltemp: .long 0
.text
//----------------------------------------------------------------------
// hull-point test
//----------------------------------------------------------------------
#define hull 4+8 // because only partially pushed
#define num 8+4 // because only partially pushed
#define p 12+12 // because only partially pushed
.align 4
.globl C(SV_HullPointContents)
C(SV_HullPointContents):
pushl %edi // preserve register variables
movl num(%esp),%eax
testl %eax,%eax
js Lhquickout
// float d;
// dclipnode_t *node;
// mplane_t *plane;
pushl %ebx
movl hull(%esp),%ebx
pushl %ebp
movl p(%esp),%edx
movl hu_clipnodes(%ebx),%edi
movl hu_planes(%ebx),%ebp
subl %ebx,%ebx
pushl %esi
// %ebx: 0
// %eax: num
// %edx: p
// %edi: hull->clipnodes
// %ebp: hull->planes
// while (num >= 0)
// {
Lhloop:
// node = hull->clipnodes + num;
// plane = hull->planes + node->planenum;
// !!! if the size of dclipnode_t changes, the scaling of %eax needs to be
// changed !!!
movl nd_planenum(%edi,%eax,8),%ecx
movl nd_children(%edi,%eax,8),%eax
movl %eax,%esi
rorl $16,%eax
leal (%ecx,%ecx,4),%ecx
// if (plane->type < 3)
// d = p[plane->type] - plane->dist;
movb pl_type(%ebp,%ecx,4),%bl
cmpb $3,%bl
jb Lnodot
// else
// d = DotProduct (plane->normal, p) - plane->dist;
flds pl_normal(%ebp,%ecx,4)
fmuls 0(%edx)
flds pl_normal+4(%ebp,%ecx,4)
fmuls 4(%edx)
flds pl_normal+8(%ebp,%ecx,4)
fmuls 8(%edx)
fxch %st(1)
faddp %st(0),%st(2)
faddp %st(0),%st(1)
fsubs pl_dist(%ebp,%ecx,4)
jmp Lsub
Lnodot:
flds pl_dist(%ebp,%ecx,4)
fsubrs (%edx,%ebx,4)
Lsub:
sarl $16,%eax
sarl $16,%esi
// if (d < 0)
// num = node->children[1];
// else
// num = node->children[0];
fstps Ltemp
movl Ltemp,%ecx
sarl $31,%ecx
andl %ecx,%esi
xorl $0xFFFFFFFF,%ecx
andl %ecx,%eax
orl %esi,%eax
jns Lhloop
// return num;
Lhdone:
popl %esi
popl %ebp
popl %ebx // restore register variables
Lhquickout:
popl %edi
ret
#endif // id386