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- #include "app.h"
- int earead_check_addrerr = 1, eawrite_check_addrerr = 0;
- // some ops use non-standard cycle counts for EAs, so are listed here.
- // all constants borrowed from the MUSASHI core by Karl Stenerud.
- /* Extra cycles for JMP instruction (000, 010) */
- int g_jmp_cycle_table[8] =
- {
- 4, /* EA_MODE_AI */
- 6, /* EA_MODE_DI */
- 10, /* EA_MODE_IX */
- 6, /* EA_MODE_AW */
- 8, /* EA_MODE_AL */
- 6, /* EA_MODE_PCDI */
- 10, /* EA_MODE_PCIX */
- 0, /* EA_MODE_I */
- };
- /* Extra cycles for JSR instruction (000, 010) */
- int g_jsr_cycle_table[8] =
- {
- 4, /* EA_MODE_AI */
- 6, /* EA_MODE_DI */
- 10, /* EA_MODE_IX */
- 6, /* EA_MODE_AW */
- 8, /* EA_MODE_AL */
- 6, /* EA_MODE_PCDI */
- 10, /* EA_MODE_PCIX */
- 0, /* EA_MODE_I */
- };
- /* Extra cycles for LEA instruction (000, 010) */
- int g_lea_cycle_table[8] =
- {
- 4, /* EA_MODE_AI */
- 8, /* EA_MODE_DI */
- 12, /* EA_MODE_IX */
- 8, /* EA_MODE_AW */
- 12, /* EA_MODE_AL */
- 8, /* EA_MODE_PCDI */
- 12, /* EA_MODE_PCIX */
- 0, /* EA_MODE_I */
- };
- /* Extra cycles for PEA instruction (000, 010) */
- int g_pea_cycle_table[8] =
- {
- 6, /* EA_MODE_AI */
- 10, /* EA_MODE_DI */
- 14, /* EA_MODE_IX */
- 10, /* EA_MODE_AW */
- 14, /* EA_MODE_AL */
- 10, /* EA_MODE_PCDI */
- 14, /* EA_MODE_PCIX */
- 0, /* EA_MODE_I */
- };
- /* Extra cycles for MOVEM instruction (000, 010) */
- int g_movem_cycle_table[8] =
- {
- 0, /* EA_MODE_AI */
- 4, /* EA_MODE_DI */
- 6, /* EA_MODE_IX */
- 4, /* EA_MODE_AW */
- 8, /* EA_MODE_AL */
- 0, /* EA_MODE_PCDI */
- 0, /* EA_MODE_PCIX */
- 0, /* EA_MODE_I */
- };
- // add nonstandard EA
- int Ea_add_ns(int *tab, int ea)
- {
- if(ea<0x10) return 0;
- if((ea&0x38)==0x10) return tab[0]; // (An) (ai)
- if(ea<0x28) return 0;
- if(ea<0x30) return tab[1]; // ($nn,An) (di)
- if(ea<0x38) return tab[2]; // ($nn,An,Rn) (ix)
- if(ea==0x38) return tab[3]; // (aw)
- if(ea==0x39) return tab[4]; // (al)
- if(ea==0x3a) return tab[5]; // ($nn,PC) (pcdi)
- if(ea==0x3b) return tab[6]; // ($nn,pc,Rn) (pcix)
- if(ea==0x3c) return tab[7]; // #$nnnn (i)
- return 0;
- }
- // ---------------------------------------------------------------------------
- // Gets the offset of a register for an ea, and puts it in 'r'
- // Shifted left by 'shift'
- // Doesn't trash anything
- static int EaCalcReg(int r,int ea,int mask,int forceor,int shift,int noshift=0)
- {
- int i=0,low=0,needor=0;
- int lsl=0;
- for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is
- mask&=0xf<<low; // This is the max we can do
- if (ea>=8)
- {
- needor=1; // Need to OR to access A0-7
- if ((g_op>>low)&8) { needor=0; mask|=8<<low; } // Ah - no we don't actually need to or, since the bit is high in r8
- if (forceor) needor=1; // Special case for 0x30-0x38 EAs ;)
- }
- ot(" and r%d,r8,#0x%.4x\n",r,mask);
- if (needor) ot(" orr r%d,r%d,#0x%x ;@ A0-7\n",r,r,8<<low);
- // Find out amount to shift left:
- lsl=shift-low;
- if (lsl&&!noshift)
- {
- ot(" mov r%d,r%d,",r,r);
- if (lsl>0) ot("lsl #%d\n", lsl);
- else ot("lsr #%d\n",-lsl);
- }
- return 0;
- }
- // EaCalc - ARM Register 'a' = Effective Address
- // If ea>=0x10, trashes r0,r2 and r3, else nothing
- // size values 0, 1, 2 ~ byte, word, long
- // mask shows usable bits in r8
- int EaCalc(int a,int mask,int ea,int size,int top,int sign_extend)
- {
- char text[32]="";
- int func=0;
- DisaPc=2; DisaGetEa(text,ea,size); // Get text version of the effective address
- func=0x68+(size<<2); // Get correct read handler
- if (ea<0x10)
- {
- int noshift=0;
- if (size>=2||(size==0&&(top||!sign_extend))) noshift=1; // Saves one opcode
- ot(";@ EaCalc : Get register index into r%d:\n",a);
- EaCalcReg(a,ea,mask,0,2,noshift);
- return 0;
- }
-
- ot(";@ EaCalc : Get '%s' into r%d:\n",text,a);
- // (An), (An)+, -(An)
- if (ea<0x28)
- {
- int step=1<<size, strr=a;
- int low=0,lsl=0,i;
- if ((ea&7)==7 && step<2) step=2; // move.b (a7)+ or -(a7) steps by 2 not 1
- if (ea==0x1f||ea==0x27) // A7 handlers are always separate
- {
- ot(" ldr r%d,[r7,#0x3c] ;@ A7\n",a);
- }
- else
- {
- EaCalcReg(2,ea,mask,0,0,1);
- if(mask)
- for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is
- lsl=2-low; // Having a lsl #x here saves one opcode
- if (lsl>=0) ot(" ldr r%d,[r7,r2,lsl #%i]\n",a,lsl);
- else if (lsl<0) ot(" ldr r%d,[r7,r2,lsr #%i]\n",a,-lsl);
- }
- if ((ea&0x38)==0x18) // (An)+
- {
- ot(" add r3,r%d,#%d ;@ Post-increment An\n",a,step);
- strr=3;
- }
- if ((ea&0x38)==0x20) // -(An)
- ot(" sub r%d,r%d,#%d ;@ Pre-decrement An\n",a,a,step);
- if ((ea&0x38)==0x18||(ea&0x38)==0x20)
- {
- if (ea==0x1f||ea==0x27)
- {
- ot(" str r%d,[r7,#0x3c] ;@ A7\n",strr);
- }
- else
- {
- if (lsl>=0) ot(" str r%d,[r7,r2,lsl #%i]\n",strr,lsl);
- else if (lsl<0) ot(" str r%d,[r7,r2,lsr #%i]\n",strr,-lsl);
- }
- }
- if ((ea&0x38)==0x20) Cycles+=size<2 ? 6:10; // -(An) Extra cycles
- else Cycles+=size<2 ? 4:8; // (An),(An)+ Extra cycles
- return 0;
- }
- if (ea<0x30) // ($nn,An) (di)
- {
- ot(" ldrsh r0,[r4],#2 ;@ Fetch offset\n"); pc_dirty=1;
- EaCalcReg(2,8,mask,0,0);
- ot(" ldr r2,[r7,r2,lsl #2]\n");
- ot(" add r%d,r0,r2 ;@ Add on offset\n",a);
- Cycles+=size<2 ? 8:12; // Extra cycles
- return 0;
- }
- if (ea<0x38) // ($nn,An,Rn) (ix)
- {
- ot(";@ Get extension word into r3:\n");
- ot(" ldrh r3,[r4],#2 ;@ ($Disp,PC,Rn)\n"); pc_dirty=1;
- ot(" mov r2,r3,lsr #10\n");
- ot(" tst r3,#0x0800 ;@ Is Rn Word or Long\n");
- ot(" and r2,r2,#0x3c ;@ r2=Index of Rn\n");
- ot(" ldreqsh r2,[r7,r2] ;@ r2=Rn.w\n");
- ot(" ldrne r2,[r7,r2] ;@ r2=Rn.l\n");
- ot(" mov r0,r3,asl #24 ;@ r0=Get 8-bit signed Disp\n");
- ot(" add r3,r2,r0,asr #24 ;@ r3=Disp+Rn\n");
- EaCalcReg(2,8,mask,1,0);
- ot(" ldr r2,[r7,r2,lsl #2]\n");
- ot(" add r%d,r2,r3 ;@ r%d=Disp+An+Rn\n",a,a);
- Cycles+=size<2 ? 10:14; // Extra cycles
- return 0;
- }
- if (ea==0x38) // (aw)
- {
- ot(" ldrsh r%d,[r4],#2 ;@ Fetch Absolute Short address\n",a); pc_dirty=1;
- Cycles+=size<2 ? 8:12; // Extra cycles
- return 0;
- }
- if (ea==0x39) // (al)
- {
- ot(" ldrh r2,[r4],#2 ;@ Fetch Absolute Long address\n");
- ot(" ldrh r0,[r4],#2\n"); pc_dirty=1;
- ot(" orr r%d,r0,r2,lsl #16\n",a);
- Cycles+=size<2 ? 12:16; // Extra cycles
- return 0;
- }
- if (ea==0x3a) // ($nn,PC) (pcdi)
- {
- ot(" ldr r0,[r7,#0x60] ;@ Get Memory base\n");
- ot(" sub r0,r4,r0 ;@ Real PC\n");
- ot(" ldrsh r2,[r4],#2 ;@ Fetch extension\n"); pc_dirty=1;
- ot(" mov r0,r0,lsl #8\n");
- ot(" add r%d,r2,r0,asr #8 ;@ ($nn,PC)\n",a);
- Cycles+=size<2 ? 8:12; // Extra cycles
- return 0;
- }
- if (ea==0x3b) // ($nn,pc,Rn) (pcix)
- {
- ot(" ldr r0,[r7,#0x60] ;@ Get Memory base\n");
- ot(" ldrh r3,[r4] ;@ Get extension word\n");
- ot(" sub r0,r4,r0 ;@ r0=PC\n");
- ot(" add r4,r4,#2\n"); pc_dirty=1;
- ot(" mov r0,r0,asl #8 ;@ use only 24bits of PC\n");
- ot(" mov r2,r3,lsr #10\n");
- ot(" tst r3,#0x0800 ;@ Is Rn Word or Long\n");
- ot(" and r2,r2,#0x3c ;@ r2=Index of Rn\n");
- ot(" ldreqsh r2,[r7,r2] ;@ r2=Rn.w\n");
- ot(" ldrne r2,[r7,r2] ;@ r2=Rn.l\n");
- ot(" mov r3,r3,asl #24 ;@ r3=Get 8-bit signed Disp\n");
- ot(" add r2,r2,r3,asr #24 ;@ r2=Disp+Rn\n");
- ot(" add r%d,r2,r0,asr #8 ;@ r%d=Disp+PC+Rn\n",a,a);
- Cycles+=size<2 ? 10:14; // Extra cycles
- return 0;
- }
- if (ea==0x3c) // #$nnnn (i)
- {
- if (size<2)
- {
- ot(" ldr%s r%d,[r4],#2 ;@ Fetch immediate value\n",Sarm[size&3],a); pc_dirty=1;
- Cycles+=4; // Extra cycles
- return 0;
- }
- ot(" ldrh r2,[r4],#2 ;@ Fetch immediate value\n");
- ot(" ldrh r3,[r4],#2\n"); pc_dirty=1;
- ot(" orr r%d,r3,r2,lsl #16\n",a);
- Cycles+=8; // Extra cycles
- return 0;
- }
- return 1;
- }
- // ---------------------------------------------------------------------------
- // Read effective address in (ARM Register 'a') to ARM register 'v'
- // 'a' and 'v' can be anything but 0 is generally best (for both)
- // If (ea<0x10) nothing is trashed, else r0-r3 is trashed
- // If 'top' is given, the ARM register v shifted to the top, e.g. 0xc000 -> 0xc0000000
- // If top is 0 and sign_extend is not, then ARM register v is sign extended,
- // e.g. 0xc000 -> 0xffffc000 (else it may or may not be sign extended)
- int EaRead(int a,int v,int ea,int size,int mask,int top,int sign_extend)
- {
- char text[32]="";
- int shift=0;
-
- shift=32-(8<<size);
- DisaPc=2; DisaGetEa(text,ea,size); // Get text version of the effective address
- if (ea<0x10)
- {
- int lsl=0,low=0,nsarm=size&3,i;
- if (size>=2||(size==0&&(top||!sign_extend))) {
- if(mask)
- for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is
- lsl=2-low; // Having a lsl #2 here saves one opcode
- }
- if (top||!sign_extend) nsarm=3;
- ot(";@ EaRead : Read register[r%d] into r%d:\n",a,v);
- if (lsl>0) ot(" ldr%s r%d,[r7,r%d,lsl #%i]\n",Narm[nsarm],v,a,lsl);
- else if (lsl<0) ot(" ldr%s r%d,[r7,r%d,lsr #%i]\n",Narm[nsarm],v,a,-lsl);
- else ot(" ldr%s r%d,[r7,r%d]\n",Sarm[nsarm],v,a);
- if (top&&shift) ot(" mov r%d,r%d,asl #%d\n",v,v,shift);
- ot("\n"); return 0;
- }
- ot(";@ EaRead : Read '%s' (address in r%d) into r%d:\n",text,a,v);
- if (ea==0x3c)
- {
- int asl=0;
- if (top) asl=shift;
- if (asl) ot(" mov r%d,r%d,asl #%d\n",v,a,asl);
- else if (v!=a) ot(" mov r%d,r%d\n",v,a);
- ot("\n"); return 0;
- }
- if (ea>=0x3a && ea<=0x3b) MemHandler(2,size,a,earead_check_addrerr); // Fetch
- else MemHandler(0,size,a,earead_check_addrerr); // Read
- // defaults to 1, as most things begins with a read
- earead_check_addrerr=1;
- if (sign_extend)
- {
- int d_reg=0;
- if (shift) {
- ot(" mov r%d,r%d,asl #%d\n",v,d_reg,shift);
- d_reg=v;
- }
- if (!top && shift) {
- ot(" mov r%d,r%d,asr #%d\n",v,d_reg,shift);
- d_reg=v;
- }
- if (d_reg != v)
- ot(" mov r%d,r%d\n",v,d_reg);
- }
- else
- {
- if (top && shift)
- ot(" mov r%d,r0,asl #%d\n",v,shift);
- else if (v!=0)
- ot(" mov r%d,r0\n",v);
- }
- ot("\n"); return 0;
- }
- // calculate EA and read
- // if (ea < 0x10) nothing is trashed
- // if (ea == 0x3c) r2 and r3 are trashed
- // else r0-r3 are trashed
- // size values 0, 1, 2 ~ byte, word, long
- // r_ea is reg to store ea in (-1 means ea is not needed), r is dst reg
- // if sign_extend is 0, non-32bit values will have MS bits undefined
- int EaCalcRead(int r_ea,int r,int ea,int size,int mask,int sign_extend)
- {
- if (ea<0x10)
- {
- if (r_ea==-1)
- {
- r_ea=r;
- if (!sign_extend) size=2;
- }
- }
- else if (ea==0x3c) // #imm
- {
- r_ea=r;
- }
- else
- {
- if (r_ea==-1) r_ea=0;
- }
- EaCalc (r_ea,mask,ea,size,0,sign_extend);
- EaRead (r_ea, r,ea,size,mask,0,sign_extend);
- return 0;
- }
- int EaCalcReadNoSE(int r_ea,int r,int ea,int size,int mask)
- {
- return EaCalcRead(r_ea,r,ea,size,mask,0);
- }
- // Return 1 if we can read this ea
- int EaCanRead(int ea,int size)
- {
- if (size<0)
- {
- // LEA:
- // These don't make sense?:
- if (ea< 0x10) return 0; // Register
- if (ea==0x3c) return 0; // Immediate
- if (ea>=0x18 && ea<0x28) return 0; // Pre/Post inc/dec An
- }
- if (ea<=0x3c) return 1;
- return 0;
- }
- // ---------------------------------------------------------------------------
- // Write effective address (ARM Register 'a') with ARM register 'v'
- // Trashes r0-r3,r12,lr; 'a' can be 0 or 2+, 'v' can be 1 or higher
- // If a==0 and v==1 it's faster though.
- int EaWrite(int a,int v,int ea,int size,int mask,int top,int sign_extend_ea)
- {
- char text[32]="";
- int shift=0;
- if(a == 1) { printf("Error! EaWrite a==1 !\n"); return 1; }
- if (top) shift=32-(8<<size);
- DisaPc=2; DisaGetEa(text,ea,size); // Get text version of the effective address
- if (ea<0x10)
- {
- int lsl=0,low=0,i;
- if (size>=2||(size==0&&(top||!sign_extend_ea))) {
- if(mask)
- for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is
- lsl=2-low; // Having a lsl #x here saves one opcode
- }
- ot(";@ EaWrite: r%d into register[r%d]:\n",v,a);
- if (shift) ot(" mov r%d,r%d,asr #%d\n",v,v,shift);
- if (lsl>0) ot(" str%s r%d,[r7,r%d,lsl #%i]\n",Narm[size&3],v,a,lsl);
- else if (lsl<0) ot(" str%s r%d,[r7,r%d,lsr #%i]\n",Narm[size&3],v,a,-lsl);
- else ot(" str%s r%d,[r7,r%d]\n",Narm[size&3],v,a);
- ot("\n"); return 0;
- }
- ot(";@ EaWrite: Write r%d into '%s' (address in r%d):\n",v,text,a);
- if (ea==0x3c) { ot("Error! Write EA=0x%x\n\n",ea); return 1; }
- if (shift) ot(" mov r1,r%d,asr #%d\n",v,shift);
- else if (v!=1) ot(" mov r1,r%d\n",v);
- MemHandler(1,size,a,eawrite_check_addrerr); // Call write handler
- // not check by default, because most cases are rmw and
- // address was already checked before reading
- eawrite_check_addrerr = 0;
- ot("\n"); return 0;
- }
- // Return 1 if we can write this ea
- int EaCanWrite(int ea)
- {
- if (ea<=0x39) return 1; // 3b?
- return 0;
- }
- // ---------------------------------------------------------------------------
- // Return 1 if EA is An reg
- int EaAn(int ea)
- {
- if((ea&0x38)==8) return 1;
- return 0;
- }
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