a_nasm.asm

小型游戏引擎

; // "Build Engine & Tools" Copyright (c) 1993-1997 Ken Silverman
; // Ken Silverman's official web site: "http://www.advsys.net/ken"
; // See the included license file "BUILDLIC.TXT" for license info.
; // This file has been modified from Ken Silverman's original release

; These two aren't needed AH
;.586P
;.8087

;include mmx.inc       ;Include this if using < WATCOM 11.0 WASM

;Warning: IN THIS FILE, ALL SEGMENTS ARE REMOVED.  THIS MEANS THAT DS:[]
;MUST BE ADDED FOR ALL SELF-MODIFIES FOR MASM TO WORK.
;
;WASM PROBLEMS:
;   1. Requires all scaled registers (*1,*2,*4,*8) to be last thing on line
;   2. Using 'DATA' is nice for self-mod. code, but WDIS only works with 'CODE'
;
;MASM PROBLEMS:
;   1. Requires DS: to be written out for self-modifying code to work
;   2. Doesn't encode short jumps automatically like WASM
;   3. Stupidly adds wait prefix to ffree's

; ************************
; **  Start Data Block  **
; ************************
SECTION .data

    ; Some C compilers insert an underscore ('_') character in front of
    ;  identifiers. In such a case, we need to redefine our references to
    ;  global indentifiers that exist in the C code.  --ryan.
%ifdef C_IDENTIFIERS_UNDERSCORED
%define asm1 _asm1
%define asm2 _asm2
%define asm3 _asm3
%define asm4 _asm4
%define fpuasm _fpuasm
%define reciptable _reciptable
%define globalx3 _globalx3
%define globaly3 _globaly3
%define ylookup _ylookup
%define vplce _vplce
%define vince _vince
%define palookupoffse _palookupoffse
%define bufplce _bufplce
%define ebpbak _ebpbak
%define espbak _espbak
%define pow2char _pow2char
%define pow2long _pow2long
%endif

extern asm1
extern asm2
extern asm3
extern asm4
extern fpuasm
extern reciptable
extern globalx3
extern globaly3
extern ylookup

extern vplce
extern vince
extern palookupoffse
extern bufplce

extern ebpbak
extern espbak

extern pow2char
extern pow2long

; These are our globally-scoped labels (i.e. functions) AH
  global _asm_krecipasm
  global _asm_sethlinesizes
  global _asm_prosethlinesizes
  global _asm_setvlinebpl
  global _asm_setpalookupaddress
  global _asm_prosetpalookupaddress
  global _asm_setuphlineasm4
  global _asm_hlineasm4
  global _asm_prohlineasm4
  global _asm_setupvlineasm
  global _asm_prosetupvlineasm
  global _asm_setupmvlineasm
  global _asm_setuptvlineasm
  global _asm_prevlineasm1
  global _asm_vlineasm1
  global _asm_mvlineasm1
  global _asm_fixtransluscence
  global _asm_settransnormal
  global _asm_settransreverse
  global _asm_tvlineasm1
  global _asm_vlineasm4
  global _asm_provlineasm4
  global _asm_mvlineasm4
  global _asm_setupspritevline
  global _asm_spritevline
  global _asm_msetupspritevline
  global _asm_mspritevline
  global _asm_tsetupspritevline
  global _asm_tspritevline
  global _asm_msethlineshift
  global _asm_mhline
  global _asm_mhlineskipmodify
  global _asm_tsethlineshift
  global _asm_thline
  global _asm_thlineskipmodify
  global _asm_setuptvlineasm2
  global _asm_tvlineasm2
  global _asm_setupslopevlin2
  global _asm_slopevlin2
  global _asm_setupslopevlin
  global _asm_slopevlin
  global _asm_setuprhlineasm4
  global _asm_rhlineasm4
  global _asm_setuprmhlineasm4
  global _asm_rmhlineasm4
  global _asm_setupqrhlineasm4
  global _asm_qrhlineasm4
  global _asm_setupdrawslab
  global _asm_drawslab
  global _asm_stretchhline
  global _asm_mmxoverlay

  global _asm_isvmwarerunning


; ************************
; **   End Data Block   **
; ************************


; ************************
; **  Start Code Block  **
; ************************
SEGMENT .text

; Ignore all the 'offset's in the code AH
%idefine offset

; Align entire code block to 16 bit boundaries
ALIGN 16

_asm_isvmwarerunning:
	mov eax,564d5868h
	mov ecx,0000000ah
	mov dx,5658h
	in  eax,dx
	cmp ebx,564d5868h
	jz  vmware_y
	xor eax,eax
	ret
vmware_y:
        mov eax,1h
        ret

 
_asm_sethlinesizes:
	mov byte [machxbits1+2], al
	mov byte [machxbits2+2], al
	mov byte [machxbits3+2], al
	neg al
	mov byte [hxsiz1+2], al
	mov byte [hxsiz2+2], al
	mov byte [hxsiz3+2], al
	mov byte [hxsiz4+2], al
	mov byte [machnegxbits1+2], al

	mov byte [hysiz1+3], bl
	mov byte [hysiz2+3], bl
	mov byte [hysiz3+3], bl
	mov byte [hysiz4+3], bl
	mov byte [hmach3a+2], bl
	mov byte [hmach3b+2], bl
	mov byte [hmach3c+2], bl
	mov byte [hmach3d+2], bl

	mov dword [hoffs1+2], ecx
	mov dword [hoffs2+2], ecx
	mov dword [hoffs3+2], ecx
	mov dword [hoffs4+2], ecx
	mov dword [hoffs5+2], ecx
	mov dword [hoffs6+2], ecx
	mov dword [hoffs7+2], ecx
	mov dword [hoffs8+2], ecx

	mov edx, -1
	mov cl, al
	sub cl, bl
	shr edx, cl
	mov dword [hmach2a+1], edx
	mov dword [hmach2b+1], edx
	mov dword [hmach2c+1], edx
	mov dword [hmach2d+1], edx
   ret

ALIGN 16
_asm_prosethlinesizes:
	mov dword [prohbuf-4], ecx
	neg eax
	mov ecx, eax
	sub eax, ebx
	mov byte [prohshru-1], al   ;bl = 32-al-bl
	mov eax, -1
	shr eax, cl
	mov ecx, ebx
	shl eax, cl
	mov dword [prohand-4], eax  ;((-1>>(-oal))<<obl)
	neg ebx
	mov byte [prohshrv-1], bl   ;bl = 32-bl
	ret

ALIGN 16	
_asm_setvlinebpl:
	mov dword [fixchain1a+2], eax
	mov dword [fixchain1b+2], eax
	mov dword [fixchain1m+2], eax
	mov dword [fixchain1t+2], eax
	mov dword [fixchain1s+2], eax
	mov dword [mfixchain1s+2], eax
	mov dword [tfixchain1s+2], eax
	mov dword [fixchain2a+2], eax
	mov dword [profixchain2a+2], eax
	mov dword [fixchain2ma+2], eax
	mov dword [fixchain2mb+2], eax
	mov dword [fixchaint2a+1], eax
	mov dword [fixchaint2b+2], eax
	mov dword [fixchaint2c+2], eax
	mov dword [fixchaint2d+2], eax
	mov dword [fixchaint2e+2], eax
    ret

ALIGN 16
_asm_setpalookupaddress:
    mov dword [pal1+2], eax
	mov dword [pal2+2], eax
	mov dword [pal3+2], eax
	mov dword [pal4+2], eax
	mov dword [pal5+2], eax
	mov dword [pal6+2], eax
	mov dword [pal7+2], eax
	mov dword [pal8+2], eax
	ret

ALIGN 16
_asm_prosetpalookupaddress:
	mov dword [prohpala-4], eax
	ret

ALIGN 16
_asm_setuphlineasm4:
machxbits3: rol eax, 6                     ;xbits
    mov dword [hmach4a+2], eax
	mov dword [hmach4b+2], eax
	mov bl, al
	mov dword [hmach4c+2], eax
	mov dword [hmach4d+2], eax
	mov dword [hmach1a+2], ebx
	mov dword [hmach1b+2], ebx
	mov dword [hmach1c+2], ebx
	mov dword [hmach1d+2], ebx
    ret

	;Non-256-stuffed ceiling&floor method with NO SHLD!:
	;yinc&0xffffff00   lea eax, [edx+88888800h]           1     1/2
	;ybits...xbits     and edx, 88000088h                 1     1/2
	;ybits             rol edx, 6                         2     1/2
	;xinc<<xbits       add esi, 88888888h                 1     1/2
	;xinc>>(32-xbits)  adc al, 88h                        1     1/2
	;bufplc            mov cl, byte [edx+88888888h]   1     1/2
	;paloffs&255       mov bl, byte [ecx+88888888h]   1     1/2

_asm_hlineasm4:
	push ebp

	lea ebp, [eax+1]

	cmp ebp, 8
	jle NEAR shorthline

	test edi, 1
	jnz short skipthe1byte

	mov eax, esi
hxsiz1: shr eax, 26
hysiz1: shld eax, edx, 6
hoffs1: mov cl, byte [eax+88888888h]
pal1: mov bl, byte [ecx+88888888h]
	sub esi, [asm1]
	sub edx, [asm2]
	mov byte [edi], bl
	dec edi
	dec ebp

skipthe1byte:
	test edi, 2
	jnz short skipthe2byte

	mov eax, esi
hxsiz2: shr eax, 26
hysiz2: shld eax, edx, 6
hoffs2: mov cl, byte [eax+88888888h]
pal2: mov bh, byte [ecx+88888888h]
	sub esi, [asm1]
	sub edx, [asm2]

	mov eax, esi
hxsiz3: shr eax, 26
hysiz3: shld eax, edx, 6
hoffs3: mov cl, byte [eax+88888888h]
pal3: mov bl, byte [ecx+88888888h]
	sub esi, [asm1]
	sub edx, [asm2]
	mov word [edi-1], bx
	sub edi, 2
	sub ebp, 2

skipthe2byte:

	mov eax, esi
machxbits1: shl esi, 6                     ;xbits
machnegxbits1: shr eax, 32-6               ;32-xbits
	mov dl, al

	inc edi

	add ebx, ebx
	mov eax, edx
	jc beginhline64

	mov eax, [asm1]
machxbits2: rol eax, 6                     ;xbits
	mov dword [hmach4a+2], eax
	mov dword [hmach4b+2], eax
	mov dword [hmach4c+2], eax
	mov dword [hmach4d+2], eax
	mov ebx, eax
	mov eax, [asm2]
	mov al, bl
	mov dword [hmach1a+2], eax
	mov dword [hmach1b+2], eax
	mov dword [hmach1c+2], eax
	mov dword [hmach1d+2], eax

	mov eax, edx
	jmp beginhline64

prebeginhline64:
	mov dword [edi], ebx
beginhline64:

hmach3a: rol eax, 6
hmach2a: and eax, 00008888h
hmach4a: sub esi, 88888888h
hmach1a: sbb edx, 88888888h
	sub edi, 4
hoffs4: mov cl, byte [eax+88888888h]
	mov eax, edx