; ; Copyright 2020 Electronic Arts Inc. ; ; TiberianDawn.DLL and RedAlert.dll and corresponding source code 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 3 of the License, or (at your option) any later version. ; TiberianDawn.DLL and RedAlert.dll and corresponding source code is distributed ; in the hope that it will be useful, but with permitted additional restrictions ; under Section 7 of the GPL. See the GNU General Public License in LICENSE.TXT ; distributed with this program. You should have received a copy of the ; GNU General Public License along with permitted additional restrictions ; with this program. If not, see [https://github.com/electronicarts/CnC_Remastered_Collection]>. ;*************************************************************************** ;** C O N F I D E N T I A L --- W E S T W O O D S T U D I O S I N C ** ;*************************************************************************** ;* * ;* Project Name : Command & Conquer * ;* * ;* File Name : MMX.ASM * ;* * ;* Programmer : Steve Tall * ;* * ;* Start Date : May 19th, 1996 * ;* * ;* Last Update : May 19th 1996 [ST] * ;* * ;*-------------------------------------------------------------------------* ;* Functions: * ;* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - * ; include <mmx.inc> .model flat ;.686 externdef C Detect_MMX_Availability:near externdef C Single_Line_Trans_Entry:near externdef C Next_Line:near externdef C Init_MMX:near externdef C MMX_Done:near externdef EndNewShapeJumpTable:byte externdef NewShapeJumpTable:dword externdef C Single_Line_Trans:near externdef MMX_Single_Line_Trans:near .code externdef C CPUType:byte ;********************************************************************************************* ;* Detect_MMX_Availability -- Detect the presence of MMX technology. * ;* * ;* * ;* INPUT: Nothing * ;* * ;* OUTPUT: True if MMX technology is available. * ;* * ;* Warnings: * ;* * ;* Note: Based in part on CPUID32.ASM by Intel * ;* * ;* HISTORY: * ;* 05/19/96 ST : Created. * ;*===========================================================================================* Detect_MMX_Availability proc C local idflag:byte local local_cputype:byte ; MMX always available now. ST - 1/3/2019 1:31PM mov [CPUType], 5 mov eax, 1 ret ;assume processor is at least 386 ; ;check whether AC bit in eflags can be toggled. ;If not then processor is 386 mov [idflag],0 pushfd ;get Eflags in EAX pop eax mov ecx,eax ;save eflags xor eax,40000h ;toggle AC bit in eflags push eax ;new eflags on stack popfd ;move new value into eflags pushfd ;get new eflags back into eax pop eax xor eax,ecx ;if AC bit not toggled then CPU=386 mov [local_cputype],3 jz @@end_get_cpu ;cpu is 386 push ecx popfd ;restore AC bit in eflags ;processor is at least 486 ; ;Check for ability to set/clear ID flag in EFLAGS ;ID flag indicates ability of processor to execute the CPUID instruction. ;486 not guaranteed to have CPUID inst? ; mov [local_cputype],4 mov eax,ecx ;original EFLAGS xor eax,200000h ;toggle ID bit push eax popfd pushfd pop eax xor eax,ecx ;check if still toggled jz @@end_get_cpu ; Execute CPUID instruction to determine vendor, family, ; model and stepping. ; mov [idflag],1 ;flag ID is available xor eax,eax cpuid mov dword ptr [VendorID],ebx mov dword ptr [VendorID+4],edx mov dword ptr [VendorID+8],ecx mov dword ptr [VendorID+12]," " cmp eax,1 ;check if 1 is valid jl @@end_get_cpu ;inp for cpuid inst. xor eax,eax inc eax cpuid ;get stepping, model and family and ax,0f00H shr ax,08H mov [local_cputype],al @@end_get_cpu: mov al,[local_cputype] mov [CPUType],al ; ; We have the CPU type in al now. ; If we arent on at least a pentium then we can assume there is no MMX ; cmp al,5 jl @@no_mmx mov eax,1 cpuid test edx,00800000h jz @@no_mmx ; ; MMX detected - return true ; mov eax,1 ret @@no_mmx: xor eax,eax ret Detect_MMX_Availability endp ;********************************************************************************************* ;* Init_MMX -- Do any special inits required for MMX support * ;* * ;* * ;* INPUT: Nothing * ;* * ;* OUTPUT: None * ;* * ;* Warnings: * ;* * ;* HISTORY: * ;* 05/19/96 ST : Created. * ;*===========================================================================================* Init_MMX proc C mov edi,offset NewShapeJumpTable mov ecx,offset EndNewShapeJumpTable sub ecx,edi shr ecx,2 mov eax,offset Single_Line_Trans mov ebx,offset MMX_Single_Line_Trans cld @@patch_loop: repnz scasd jnz @@done mov [edi-4],ebx test ecx,ecx jnz @@patch_loop @@done: ret Init_MMX endp ;********************************************************************************************* ;* MMX_Done -- Restores floating point capability after MMX usage * ;* * ;* * ;* INPUT: Nothing * ;* * ;* OUTPUT: None * ;* * ;* Warnings: * ;* * ;* HISTORY: * ;* 05/19/96 ST : Created. * ;*===========================================================================================* MMX_Done proc C emms ret MMX_Done endp code segment page public use32 'code' ; Need stricter segment alignment ; for pentium optimisations ;********************************************************************************************* ;* MMX_Single_Line_Trans -- draw a single line of transparent pixels using MMX technology * ;* * ;* * ;* INPUT: Esi - ptr to source data * ;* Edi - ptr to destination data * ;* Ecx - width to draw in bytes * ;* * ;* OUTPUT: None * ;* * ;* Warnings: * ;* * ;* HISTORY: * ;* 05/19/96 ST : Created. * ;*===========================================================================================* align 16 MMX_Single_Line_Trans proc near ; ; If we are doing less than 8 bytes then dont use MMX ; cmp ecx,8 jge @@mmx_loop push offset Single_Line_Trans_Entry ret ; ; Use MMX instructions to mask 8 bytes at once ; ; Creates a bitmask based on the source bytes equality with zero and then uses this to mask ; out the source bytes in the destination data. The advatage that MMX gives us is that there is ; no 'test for zero then jump' required to mask. ; align 64 ;MMX instructions like 64 byte alignment! @@mmx_loop: movq mm0,[esi] ; move 8 bytes of source into mm0 pxor mm1,mm1 ; zero out mm1 pcmpeqb mm1,mm0 ; compare mm0 with 0. Bits get set in mm1 lea esi,[esi+8] ; adjust the source data pointer pand mm1,[edi] ; and in the destination data to throw away the bytes which arent zero in the source sub ecx,8 ; adjust the byte counter por mm1,mm0 ; or in the source with the destination data movq [edi],mm1 ; write back the destination data lea edi,[edi+8] ; adjust the destination pointer cmp ecx,8 jg @@mmx_loop ; ; Jump to the approprite code for drawing the end of this line or going to the next one ; push offset Next_Line jcxz @@next_line push offset Single_Line_Trans_Entry @@next_line: ret MMX_Single_Line_Trans endp code ends .data CPUType db 0 VendorID db "Not available",0,0,0,0,0,0 end