| 0,0 → 1,856 |
|---|
| |
| // This file is part of the PicoDrive Megadrive Emulator |
| |
| // Copyright (c) 2011 FinalDave (emudave (at) gmail.com) |
| |
| // This code is licensed under the GNU General Public License version 2.0 and the MAME License. |
| // You can choose the license that has the most advantages for you. |
| |
| // SVN repository can be found at http://code.google.com/p/cyclone68000/ |
| |
| // Disa 68000 Disassembler |
| #ifndef __GNUC__ |
| #pragma warning(disable:4115) |
| #endif |
| |
| #define _CRT_SECURE_NO_WARNINGS |
| #include <stdio.h> |
| #include <string.h> |
| #include "Disa.h" |
| |
| unsigned int DisaPc=0; |
| char *DisaText=NULL; // Text buffer to write in |
| static char Tasm[]="bwl?"; |
| static char Comment[64]=""; |
| unsigned short (CPU_CALL *DisaWord)(unsigned int a)=NULL; |
| |
| static unsigned int DisaLong(unsigned int a) |
| { |
| unsigned int d=0; |
| if (DisaWord==NULL) return d; |
| |
| d= DisaWord(a)<<16; |
| d|=DisaWord(a+2)&0xffff; |
| return d; |
| } |
| |
| // Get text version of the effective address |
| int DisaGetEa(char *t,int ea,int size) |
| { |
| ea&=0x3f; t[0]=0; |
| if ((ea&0x38)==0x00) { sprintf(t,"d%d",ea ); return 0; } // 000rrr |
| if ((ea&0x38)==0x08) { sprintf(t,"a%d",ea&7); return 0; } // 001rrr |
| if ((ea&0x38)==0x10) { sprintf(t,"(a%d)",ea&7); return 0; } // 010rrr |
| if ((ea&0x38)==0x18) { sprintf(t,"(a%d)+",ea&7); return 0; } // 011rrr |
| if ((ea&0x38)==0x20) { sprintf(t,"-(a%d)",ea&7); return 0; } // 100rrr |
| if ((ea&0x38)==0x28) { sprintf(t,"($%x,a%d)",DisaWord(DisaPc)&0xffff,ea&7); DisaPc+=2; return 0; } // 101rrr |
| |
| if ((ea&0x38)==0x30) |
| { |
| // 110nnn - An + Disp + D/An |
| int areg=0,ext=0,off=0,da=0,reg=0,wol=0,scale=0; |
| ext=DisaWord(DisaPc)&0xffff; |
| |
| areg=ea&7; |
| off=ext&0xff; da =ext&0x8000?'a':'d'; |
| reg=(ext>>12)&7; wol=ext&0x0800?'l':'w'; |
| scale=1<<((ext>>9)&3); |
| |
| if (scale<2) sprintf(t,"($%x,a%d,%c%d.%c)", off,areg,da,reg,wol); |
| else sprintf(t,"($%x,a%d,%c%d.%c*%d)",off,areg,da,reg,wol,scale); // 68020 |
| |
| DisaPc+=2; |
| return 0; |
| } |
| |
| if (ea==0x38) { sprintf(t,"$%x.w",DisaWord(DisaPc)&0xffff); DisaPc+=2; return 0; } // 111000 - Absolute short |
| if (ea==0x39) { sprintf(t,"$%x.l",DisaLong(DisaPc)); DisaPc+=4; return 0; } // 111001 - Absolute long |
| |
| if (ea==0x3a) |
| { |
| // 111010 - PC Relative |
| int ext=DisaWord(DisaPc)&0xffff; |
| sprintf(t,"($%x,pc)",ext); |
| sprintf(Comment,"; =%x",DisaPc+(short)ext); // Comment where pc+ext is |
| DisaPc+=2; |
| return 0; |
| } |
| |
| if (ea==0x3b) |
| { |
| // 111011 - PC Relative + D/An |
| int ext=0,off=0,da=0,reg=0,wol=0,scale=0; |
| ext=DisaWord(DisaPc)&0xffff; |
| |
| off=ext&0xff; da =ext&0x8000?'a':'d'; |
| reg=(ext>>12)&7; wol=ext&0x0800?'l':'w'; |
| scale=1<<((ext>>9)&3); |
| |
| if (scale<2) sprintf(t,"($%x,pc,%c%d.%c)", off,da,reg,wol); |
| else sprintf(t,"($%x,pc,%c%d.%c*%d)",off,da,reg,wol,scale); // 68020 |
| |
| sprintf(Comment,"; =%x",DisaPc+(char)off); // Comment where pc+ext is |
| DisaPc+=2; |
| return 0; |
| } |
| |
| if (ea==0x3c) |
| { |
| // 111100 - Immediate |
| switch (size) |
| { |
| case 0: sprintf(t,"#$%x",DisaWord(DisaPc)&0x00ff); DisaPc+=2; return 0; |
| case 1: sprintf(t,"#$%x",DisaWord(DisaPc)&0xffff); DisaPc+=2; return 0; |
| case 2: sprintf(t,"#$%x",DisaLong(DisaPc) ); DisaPc+=4; return 0; |
| } |
| return 1; |
| } |
| |
| // Unknown effective address |
| sprintf(t,"ea=(%d%d%d %d%d%d)", |
| (ea>>5)&1,(ea>>4)&1,(ea>>3)&1, |
| (ea>>2)&1,(ea>>1)&1, ea &1); |
| return 1; |
| } |
| |
| static void GetOffset(char *text) |
| { |
| int off=(short)DisaWord(DisaPc); DisaPc+=2; |
| |
| if (off<0) sprintf(text,"-$%x",-off); |
| else sprintf(text,"$%x", off); |
| } |
| |
| // ================ Opcodes 0x0000+ ================ |
| static int DisaArithImm(int op) |
| { |
| // Or/And/Sub/Add/Eor/Cmp Immediate 0000ttt0 xxDDDddd (tt=type, xx=size extension, DDDddd=Dest ea) |
| int dea=0; |
| char seat[64]="",deat[64]=""; |
| int type=0,size=0; |
| char *arith[8]={"or","and","sub","add","?","eor","cmp","?"}; |
| |
| type=(op>>9)&7; if (type==4 || type>=7) return 1; |
| size=(op>>6)&3; if (size>=3) return 1; |
| dea=op&0x3f; if (dea==0x3c) return 1; |
| |
| DisaGetEa(seat,0x3c,size); |
| DisaGetEa(deat,dea, size); |
| |
| sprintf(DisaText,"%si.%c %s, %s",arith[type],Tasm[size],seat,deat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x0108+ ================ |
| static int DisaMovep(int op) |
| { |
| // movep.x (Aa),Dn - 0000nnn1 dx001aaa nn |
| int dn=0,dir=0,size=0,an=0; |
| char offset[32]=""; |
| |
| dn =(op>>9)&7; |
| dir =(op>>7)&1; |
| size=(op>>6)&1; size++; |
| an = op &7; |
| |
| GetOffset(offset); |
| if (dir) sprintf(DisaText,"movep.%c d%d, (%s,a%d)",Tasm[size],dn,offset,an); |
| else sprintf(DisaText,"movep.%c (%s,a%d), d%d",Tasm[size],offset,an,dn); |
| |
| return 0; |
| } |
| |
| // ================ Opcodes 0x007c+ ================ |
| static int DisaArithSr(int op) |
| { |
| // Ori/Andi/Eori $nnnn,sr 0000t0tx 0s111100 |
| char *opcode[6]={"ori","andi","","","","eori"}; |
| char seat[64]=""; |
| int type=0,size=0; |
| |
| type=(op>>9)&5; |
| size=(op>>6)&1; |
| |
| DisaGetEa(seat,0x3c,size); |
| sprintf(DisaText,"%s.%c %s, %s", opcode[type], Tasm[size], seat, size?"sr":"ccr"); |
| |
| return 0; |
| } |
| |
| // ================ Opcodes 0x0100+ ================ |
| static int DisaBtstReg(int op) |
| { |
| // Btst/Bchg/Bclr/Bset 0000nnn1 tteeeeee (nn=reg number, eeeeee=Dest ea) |
| int type=0; |
| int sea=0,dea=0; |
| char seat[64]="",deat[64]=""; |
| char *opcode[4]={"btst","bchg","bclr","bset"}; |
| |
| sea =(op>>9)&7; |
| type=(op>>6)&3; |
| dea= op&0x3f; |
| |
| if ((dea&0x38)==0x08) return 1; // movep |
| DisaGetEa(seat,sea,0); |
| DisaGetEa(deat,dea,0); |
| |
| sprintf(DisaText,"%s %s, %s",opcode[type],seat,deat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x0800+ ================ |
| static int DisaBtstImm(int op) |
| { |
| // Btst/Bchg/Bclr/Bset 00001000 tteeeeee 00 nn (eeeeee=ea, nn=bit number) |
| int type=0; |
| char seat[64]="",deat[64]=""; |
| char *opcode[4]={"btst","bchg","bclr","bset"}; |
| |
| type=(op>>6)&3; |
| DisaGetEa(seat, 0x3c,0); |
| DisaGetEa(deat,op&0x3f,0); |
| |
| sprintf(DisaText,"%s %s, %s",opcode[type],seat,deat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x1000+ ================ |
| static int DisaMove(int op) |
| { |
| // Move 00xxdddD DDssssss (xx=size extension, ssssss=Source EA, DDDddd=Dest ea) |
| int sea=0,dea=0; |
| char inst[64]="",seat[64]="",deat[64]=""; |
| char *movea=""; |
| int size=0; |
| |
| if ((op&0x01c0)==0x0040) movea="a"; // See if it's a movea opcode |
| |
| // Find size extension |
| switch (op&0x3000) |
| { |
| case 0x1000: size=0; break; |
| case 0x3000: size=1; break; |
| case 0x2000: size=2; break; |
| default: return 1; |
| } |
| |
| sea = op&0x003f; |
| DisaGetEa(seat,sea,size); |
| |
| dea =(op&0x01c0)>>3; |
| dea|=(op&0x0e00)>>9; |
| DisaGetEa(deat,dea,size); |
| |
| sprintf(inst,"move%s.%c",movea,Tasm[size]); |
| sprintf(DisaText,"%s %s, %s",inst,seat,deat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4000+ ================ |
| static int DisaNeg(int op) |
| { |
| // 01000tt0 xxeeeeee (tt=negx/clr/neg/not, xx=size, eeeeee=EA) |
| char eat[64]=""; |
| int type=0,size=0; |
| char *opcode[4]={"negx","clr","neg","not"}; |
| |
| type=(op>>9)&3; |
| size=(op>>6)&3; if (size>=3) return 1; |
| DisaGetEa(eat,op&0x3f,size); |
| |
| sprintf(DisaText,"%s.%c %s",opcode[type],Tasm[size],eat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x40c0+ ================ |
| static int DisaMoveSr(int op) |
| { |
| // 01000tt0 11eeeeee (tt=type, xx=size, eeeeee=EA) |
| int type=0,ea=0; |
| char eat[64]=""; |
| |
| type=(op>>9)&3; |
| ea=op&0x3f; |
| DisaGetEa(eat,ea,1); |
| |
| switch (type) |
| { |
| default: sprintf(DisaText,"move sr, %s", eat); break; |
| case 1: sprintf(DisaText,"move ccr, %s",eat); break; |
| case 2: sprintf(DisaText,"move %s, ccr",eat); break; |
| case 3: sprintf(DisaText,"move %s, sr", eat); break; |
| } |
| return 0; |
| } |
| |
| // ================ Opcodes 0x41c0+ ================ |
| static int DisaLea(int op) |
| { |
| // Lea 0100nnn1 11eeeeee (eeeeee=ea) |
| int sea=0,dea=0; |
| char seat[64]="",deat[64]=""; |
| |
| sea=op&0x003f; |
| DisaGetEa(seat,sea,0); |
| |
| dea=(op>>9)&7; dea|=8; |
| DisaGetEa(deat,dea,2); |
| |
| sprintf(DisaText,"lea %s, %s",seat,deat); |
| return 0; |
| } |
| |
| static int MakeRegList(char *list,int mask,int ea) |
| { |
| int reverse=0,i=0,low=0,len=0; |
| |
| if ((ea&0x38)==0x20) reverse=1; // -(An), bitfield is reversed |
| |
| mask&=0xffff; list[0]=0; |
| |
| for (i=0;i<17;i++) |
| { |
| int bit=0; |
| |
| // Mask off bit i: |
| if (reverse) bit=0x8000>>i; else bit=1<<i; |
| bit&=mask; |
| |
| if (bit==0 || i==8) |
| { |
| // low to i-1 are a continuous section, add it: |
| char add[16]=""; |
| int ad=low&8?'a':'d'; |
| if (low==i-1) sprintf(add,"%c%d/", ad,low&7); |
| if (low< i-1) sprintf(add,"%c%d-%c%d/",ad,low&7, ad,(i-1)&7); |
| strcat(list,add); |
| |
| low=i; // Next section |
| } |
| |
| if (bit==0) low=i+1; |
| } |
| |
| // Knock off trailing '/' |
| len=strlen(list); |
| if (len>0) if (list[len-1]=='/') list[len-1]=0; |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4840+ ================ |
| static int DisaSwap(int op) |
| { |
| // Swap, 01001000 01000nnn swap Dn |
| sprintf(DisaText,"swap d%d",op&7); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4850+ ================ |
| static int DisaPea(int op) |
| { |
| // Pea 01001000 01eeeeee (eeeeee=ea) pea |
| int ea=0; |
| char eat[64]=""; |
| |
| ea=op&0x003f; if (ea<0x10) return 1; // swap opcode |
| DisaGetEa(eat,ea,2); |
| |
| sprintf(DisaText,"pea %s",eat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4880+ ================ |
| static int DisaExt(int op) |
| { |
| // Ext 01001000 1x000nnn (x=size, eeeeee=EA) |
| char eat[64]=""; |
| int size=0; |
| |
| size=(op>>6)&1; size++; |
| DisaGetEa(eat,op&0x3f,size); |
| |
| sprintf(DisaText,"ext.%c %s",Tasm[size],eat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4890+ ================ |
| static int DisaMovem(int op) |
| { |
| // Movem 01001d00 1xeeeeee regmask d=direction, x=size, eeeeee=EA |
| int dir=0,size=0; |
| int ea=0,mask=0; |
| char list[64]="",eat[64]=""; |
| |
| dir=(op>>10)&1; |
| size=((op>>6)&1)+1; |
| ea=op&0x3f; if (ea<0x10) return 1; // ext opcode |
| |
| mask=DisaWord(DisaPc)&0xffff; DisaPc+=2; |
| |
| MakeRegList(list,mask,ea); // Turn register mask into text |
| DisaGetEa(eat,ea,size); |
| |
| if (dir) sprintf(DisaText,"movem.%c %s, %s",Tasm[size],eat,list); |
| else sprintf(DisaText,"movem.%c %s, %s",Tasm[size],list,eat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4e40+ ================ |
| static int DisaTrap(int op) |
| { |
| sprintf(DisaText,"trap #%d",op&0xf); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4e50+ ================ |
| static int DisaLink(int op) |
| { |
| // Link opcode, 01001110 01010nnn dd link An,#offset |
| char eat[64]=""; |
| char offset[32]=""; |
| |
| DisaGetEa(eat,(op&7)|8,0); |
| GetOffset(offset); |
| |
| sprintf(DisaText,"link %s,#%s",eat,offset); |
| |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4e58+ ================ |
| static int DisaUnlk(int op) |
| { |
| // Link opcode, 01001110 01011nnn dd unlk An |
| char eat[64]=""; |
| |
| DisaGetEa(eat,(op&7)|8,0); |
| sprintf(DisaText,"unlk %s",eat); |
| |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4e60+ ================ |
| static int DisaMoveUsp(int op) |
| { |
| // Move USP opcode, 01001110 0110dnnn move An to/from USP (d=direction) |
| int ea=0,dir=0; |
| char eat[64]=""; |
| |
| dir=(op>>3)&1; |
| ea=(op&7)|8; |
| DisaGetEa(eat,ea,0); |
| |
| if (dir) sprintf(DisaText,"move usp, %s",eat); |
| else sprintf(DisaText,"move %s, usp",eat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4e70+ ================ |
| static int Disa4E70(int op) |
| { |
| char *inst[8]={"reset","nop","stop","rte","rtd","rts","trapv","rtr"}; |
| int n=0; |
| |
| n=op&7; |
| |
| sprintf(DisaText,"%s",inst[n]); |
| |
| //todo - 'stop' with 16 bit data |
| |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4a00+ ================ |
| static int DisaTst(int op) |
| { |
| // Tst 01001010 xxeeeeee (eeeeee=ea) |
| int ea=0; |
| char eat[64]=""; |
| int size=0; |
| |
| ea=op&0x003f; |
| DisaGetEa(eat,ea,0); |
| size=(op>>6)&3; if (size>=3) return 1; |
| |
| sprintf(DisaText,"tst.%c %s",Tasm[size],eat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x4e80+ ================ |
| static int DisaJsr(int op) |
| { |
| // Jsr/Jmp 0100 1110 1mEE Eeee (eeeeee=ea m=1=jmp) |
| int sea=0; |
| char seat[64]=""; |
| |
| sea=op&0x003f; |
| DisaGetEa(seat,sea,0); |
| |
| sprintf(DisaText,"j%s %s", op&0x40?"mp":"sr", seat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x5000+ ================ |
| static int DisaAddq(int op) |
| { |
| // 0101nnnt xxeeeeee (nnn=#8,1-7 t=addq/subq xx=size, eeeeee=EA) |
| int num=0,type=0,size=0,ea=0; |
| char eat[64]=""; |
| |
| num =(op>>9)&7; if (num==0) num=8; |
| type=(op>>8)&1; |
| size=(op>>6)&3; if (size>=3) return 1; |
| ea = op&0x3f; |
| |
| DisaGetEa(eat,ea,size); |
| |
| sprintf(DisaText,"%s.%c #%d, %s",type?"subq":"addq",Tasm[size],num,eat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x50c0+ ================ |
| static int DisaSet(int op) |
| { |
| // 0101cccc 11eeeeee (sxx ea) |
| static char *cond[16]= |
| {"t" ,"f", "hi","ls","cc","cs","ne","eq", |
| "vc","vs","pl","mi","ge","lt","gt","le"}; |
| char *cc=""; |
| int ea=0; |
| char eat[64]=""; |
| |
| cc=cond[(op>>8)&0xf]; // Get condition code |
| ea=op&0x3f; |
| if ((ea&0x38)==0x08) return 1; // dbra, not scc |
| |
| DisaGetEa(eat,ea,0); |
| sprintf(DisaText,"s%s %s",cc,eat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x50c8+ ================ |
| static int DisaDbra(int op) |
| { |
| // 0101cccc 11001nnn offset (dbra/dbxx Rn,offset) |
| int dea=0; char deat[64]=""; |
| int pc=0,Offset=0; |
| |
| static char *BraCode[16]= |
| {"bt" ,"bra","bhi","bls","bcc","bcs","bne","beq", |
| "bvc","bvs","bpl","bmi","bge","blt","bgt","ble"}; |
| char *Bra=""; |
| |
| dea=op&7; |
| DisaGetEa(deat,dea,2); |
| |
| // Get condition code |
| Bra=BraCode[(op>>8)&0xf]; |
| |
| // Get offset |
| pc=DisaPc; |
| Offset=(short)DisaWord(DisaPc); DisaPc+=2; |
| |
| sprintf(DisaText,"d%s %s, %x",Bra,deat,pc+Offset); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x6000+ ================ |
| static int DisaBranch(int op) |
| { |
| // Branch 0110cccc nn (cccc=condition) |
| int pc=0,Offset=0; |
| |
| static char *BraCode[16]= |
| {"bra","bsr","bhi","bls","bcc","bcs","bne","beq", |
| "bvc","bvs","bpl","bmi","bge","blt","bgt","ble"}; |
| char *Bra=""; |
| |
| // Get condition code |
| Bra=BraCode[(op>>8)&0x0f]; |
| |
| // Get offset |
| pc=DisaPc; |
| Offset=(char)(op&0xff); |
| if (Offset== 0) { Offset=(short)DisaWord(DisaPc); DisaPc+=2; } |
| else if (Offset==-1) { Offset= DisaLong(DisaPc); DisaPc+=4; } |
| |
| sprintf(DisaText,"%s %x",Bra,pc+Offset); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x7000+ ================ |
| static int DisaMoveq(int op) |
| { |
| // Moveq 0111rrr0 nn (rrr=Dest register, nn=data) |
| |
| int dea=0; char deat[64]=""; |
| char *inst="moveq"; |
| int val=0; |
| |
| dea=(op>>9)&7; |
| DisaGetEa(deat,dea,2); |
| |
| val=(char)(op&0xff); |
| sprintf(DisaText,"%s #$%x, %s",inst,val,deat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x8000+ ================ |
| static int DisaArithReg(int op) |
| { |
| // 1t0tnnnd xxeeeeee (tt=type:or/sub/and/add xx=size, eeeeee=EA) |
| int type=0,size=0,dir=0,rea=0,ea=0; |
| char reat[64]="",eat[64]=""; |
| char *opcode[]={"or","sub","","","and","add"}; |
| |
| type=(op>>12)&5; |
| rea =(op>> 9)&7; |
| dir =(op>> 8)&1; |
| size=(op>> 6)&3; if (size>=3) return 1; |
| ea = op&0x3f; |
| |
| if (dir && ea<0x10) return 1; // addx opcode |
| |
| DisaGetEa(reat,rea,size); |
| DisaGetEa( eat, ea,size); |
| |
| if (dir) sprintf(DisaText,"%s.%c %s, %s",opcode[type],Tasm[size],reat,eat); |
| else sprintf(DisaText,"%s.%c %s, %s",opcode[type],Tasm[size],eat,reat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x8100+ ================ |
| static int DisaAbcd(int op) |
| { |
| // 1t00ddd1 0000asss - sbcd/abcd Ds,Dd or -(As),-(Ad) |
| int type=0; |
| int dn=0,addr=0,sn=0; |
| char *opcode[]={"sbcd","abcd"}; |
| |
| type=(op>>14)&1; |
| dn =(op>> 9)&7; |
| addr=(op>> 3)&1; |
| sn = op &7; |
| |
| if (addr) sprintf(DisaText,"%s -(a%d), -(a%d)",opcode[type],sn,dn); |
| else sprintf(DisaText,"%s d%d, d%d", opcode[type],sn,dn); |
| |
| return 0; |
| } |
| |
| // ================ Opcodes 0x80c0+ ================ |
| static int DisaMul(int op) |
| { |
| // Div/Mul: 1m00nnns 11eeeeee (m=Mul, nnn=Register Dn, s=signed, eeeeee=EA) |
| int type=0,rea=0,sign=0,ea=0,size=1; |
| char reat[64]="",eat[64]=""; |
| char *opcode[2]={"div","mul"}; |
| |
| type=(op>>14)&1; // div/mul |
| rea =(op>> 9)&7; |
| sign=(op>> 8)&1; |
| ea = op&0x3f; |
| |
| DisaGetEa(reat,rea,size); |
| DisaGetEa( eat, ea,size); |
| |
| sprintf(DisaText,"%s%c.%c %s, %s",opcode[type],sign?'s':'u',Tasm[size],eat,reat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0x90c0+ ================ |
| static int DisaAritha(int op) |
| { |
| // Suba/Cmpa/Adda 1tt1nnnx 11eeeeee (tt=type, x=size, eeeeee=Source EA) |
| int type=0,size=0,sea=0,dea=0; |
| char seat[64]="",deat[64]=""; |
| char *aritha[4]={"suba","cmpa","adda",""}; |
| |
| type=(op>>13)&3; if (type>=3) return 1; |
| size=(op>>8)&1; size++; |
| dea =(op>>9)&7; dea|=8; // Dest=An |
| sea = op&0x003f; // Source |
| |
| DisaGetEa(seat,sea,size); |
| DisaGetEa(deat,dea,size); |
| |
| sprintf(DisaText,"%s.%c %s, %s",aritha[type],Tasm[size],seat,deat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0xb000+ ================ |
| static int DisaCmpEor(int op) |
| { |
| // Cmp/Eor 1011rrrt xxeeeeee (rrr=Dn, t=cmp/eor, xx=size extension, eeeeee=ea) |
| char reat[64]="",eat[64]=""; |
| int type=0,size=0; |
| |
| type=(op>>8)&1; |
| size=(op>>6)&3; if (size>=3) return 1; // cmpa opcode |
| if ((op&0xf138)==0xb108) return 1; // cmpm opcode |
| |
| DisaGetEa(reat,(op>>9)&7,size); |
| DisaGetEa(eat, op&0x3f, size); |
| |
| if (type) sprintf(DisaText,"eor.%c %s, %s",Tasm[size],reat,eat); |
| else sprintf(DisaText,"cmp.%c %s, %s",Tasm[size],eat,reat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0xb108+ ================ |
| static int DisaCmpm(int op) |
| { |
| // Cmpm 1011ddd1 xx001sss |
| int type=0,size=0,dea=0,sea=0; |
| char deat[64]="",seat[64]=""; |
| |
| type=(op>>12)&5; |
| (void)type; |
| dea =(op>> 9)&7; dea|=8; |
| size=(op>> 6)&3; if (size>=3) return 1; |
| sea = op&0x3f; |
| |
| DisaGetEa(deat,dea,size); |
| DisaGetEa(seat,sea,size); |
| |
| sprintf(DisaText,"cmpm.%c (%s)+, (%s)+",Tasm[size],seat,deat); |
| |
| return 0; |
| } |
| |
| // ================ Opcodes 0xc140+ ================ |
| // 1100ttt1 01000sss exg ds,dt |
| // 1100ttt1 01001sss exg as,at |
| // 1100ttt1 10001sss exg as,dt |
| static int DisaExg(int op) |
| { |
| int tr=0,type=0,sr=0; |
| |
| tr =(op>>9)&7; |
| type= op&0xf8; |
| sr = op&7; |
| |
| if (type==0x40) sprintf(DisaText,"exg d%d, d%d",sr,tr); |
| else if (type==0x48) sprintf(DisaText,"exg a%d, a%d",sr,tr); |
| else if (type==0x88) sprintf(DisaText,"exg a%d, d%d",sr,tr); |
| else return 1; |
| |
| return 0; |
| } |
| |
| // ================ Opcodes 0xd100+ ================ |
| static int DisaAddx(int op) |
| { |
| // 1t01ddd1 xx000sss addx |
| int type=0,size=0,dea=0,sea=0; |
| char deat[64]="",seat[64]=""; |
| char *opcode[6]={"","subx","","","","addx"}; |
| |
| type=(op>>12)&5; |
| dea =(op>> 9)&7; |
| size=(op>> 6)&3; if (size>=3) return 1; |
| sea = op&0x3f; |
| |
| DisaGetEa(deat,dea,size); |
| DisaGetEa(seat,sea,size); |
| |
| sprintf(DisaText,"%s.%c %s, %s",opcode[type],Tasm[size],seat,deat); |
| return 0; |
| } |
| |
| // ================ Opcodes 0xe000+ ================ |
| static char *AsrName[4]={"as","ls","rox","ro"}; |
| static int DisaAsr(int op) |
| { |
| // Asr/l/Ror/l etc - 1110cccd xxuttnnn |
| // (ccc=count, d=direction xx=size extension, u=use reg for count, tt=type, nnn=register Dn) |
| int count=0,dir=0,size=0,usereg=0,type=0,num=0; |
| |
| count =(op>>9)&7; |
| dir =(op>>8)&1; |
| size =(op>>6)&3; if (size>=3) return 1; // todo Asr EA |
| usereg=(op>>5)&1; |
| type =(op>>3)&3; |
| num = op &7; // Register number |
| |
| if (usereg==0) count=((count-1)&7)+1; // because ccc=000 means 8 |
| |
| sprintf(DisaText,"%s%c.%c %c%d, d%d", |
| AsrName[type], dir?'l':'r', Tasm[size], |
| usereg?'d':'#', count, num); |
| return 0; |
| } |
| |
| static int DisaAsrEa(int op) |
| { |
| // Asr/l/Ror/l etc EA - 11100ttd 11eeeeee |
| int type=0,dir=0,size=1; |
| char eat[64]=""; |
| |
| type=(op>>9)&3; |
| dir =(op>>8)&1; |
| DisaGetEa(eat,op&0x3f,size); |
| |
| sprintf(DisaText,"%s%c.w %s", AsrName[type], dir?'l':'r', eat); |
| return 0; |
| } |
| |
| // ================================================================= |
| |
| static int TryOp(int op) |
| { |
| if ((op&0xf100)==0x0000) DisaArithImm(op); // Ori/And/Sub/Add/Eor/Cmp Immediate |
| if ((op&0xf5bf)==0x003c) DisaArithSr(op); // Ori/Andi/Eori $nnnn,sr |
| if ((op&0xf100)==0x0100) DisaBtstReg(op); |
| if ((op&0xf138)==0x0108) DisaMovep(op); |
| if ((op&0xff00)==0x0800) DisaBtstImm(op); // Btst/Bchg/Bclr/Bset |
| if ((op&0xc000)==0x0000) DisaMove(op); |
| if ((op&0xf900)==0x4000) DisaNeg(op); // Negx/Clr/Neg/Not |
| if ((op&0xf1c0)==0x41c0) DisaLea(op); |
| if ((op&0xf9c0)==0x40c0) DisaMoveSr(op); |
| if ((op&0xfff8)==0x4840) DisaSwap(op); |
| if ((op&0xffc0)==0x4840) DisaPea(op); |
| if ((op&0xffb8)==0x4880) DisaExt(op); |
| if ((op&0xfb80)==0x4880) DisaMovem(op); |
| if ((op&0xff00)==0x4a00) DisaTst(op); |
| if ((op&0xfff0)==0x4e40) DisaTrap(op); |
| if ((op&0xfff8)==0x4e50) DisaLink(op); |
| if ((op&0xfff8)==0x4e58) DisaUnlk(op); |
| if ((op&0xfff0)==0x4e60) DisaMoveUsp(op); |
| if ((op&0xfff8)==0x4e70) Disa4E70(op); |
| if ((op&0xff80)==0x4e80) DisaJsr(op); |
| if ((op&0xf000)==0x5000) DisaAddq(op); |
| if ((op&0xf0c0)==0x50c0) DisaSet(op); |
| if ((op&0xf0f8)==0x50c8) DisaDbra(op); |
| if ((op&0xf000)==0x6000) DisaBranch(op); |
| if ((op&0xa000)==0x8000) DisaArithReg(op); // Or/Sub/And/Add |
| if ((op&0xb1f0)==0x8100) DisaAbcd(op); |
| if ((op&0xb130)==0x9100) DisaAddx(op); |
| if ((op&0xb0c0)==0x80c0) DisaMul(op); |
| if ((op&0xf100)==0x7000) DisaMoveq(op); |
| if ((op&0x90c0)==0x90c0) DisaAritha(op); |
| if ((op&0xf000)==0xb000) DisaCmpEor(op); |
| if ((op&0xf138)==0xb108) DisaCmpm(op); |
| if ((op&0xf130)==0xc100) DisaExg(op); |
| if ((op&0xf000)==0xe000) DisaAsr(op); |
| if ((op&0xf8c0)==0xe0c0) DisaAsrEa(op); |
| |
| // Unknown opcoode |
| return 0; |
| } |
| |
| int DisaGet() |
| { |
| int op=0; |
| if (DisaWord==NULL) return 1; |
| |
| Comment[0]=0; |
| DisaText[0]=0; // Assume opcode unknown |
| |
| op=DisaWord(DisaPc)&0xffff; DisaPc+=2; |
| TryOp(op); |
| strcat(DisaText,Comment); |
| |
| // Unknown opcoode |
| return 0; |
| } |