kolibrios/programs/emulator/dgen-sdl-1.33/cyclone/OpMove.cpp
turbocat ea1a60faa3 Upload DGEN port source
git-svn-id: svn://kolibrios.org@9837 a494cfbc-eb01-0410-851d-a64ba20cac60
2022-06-15 18:25:17 +00:00

696 lines
17 KiB
C++

// This file is part of the Cyclone 68000 Emulator
// Copyright (c) 2004,2011 FinalDave (emudave (at) gmail.com)
// Copyright (c) 2005-2011 Gražvydas "notaz" Ignotas (notasas (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/
#include "app.h"
// Pack our flags into r1, in SR/CCR register format
// trashes r0,r2
void OpFlagsToReg(int high)
{
ot(" ldr r0,[r7,#0x4c] ;@ X bit\n");
ot(" mov r1,r10,lsr #28 ;@ ____NZCV\n");
ot(" eor r2,r1,r1,ror #1 ;@ Bit 0=C^V\n");
ot(" tst r2,#1 ;@ 1 if C!=V\n");
ot(" eorne r1,r1,#3 ;@ ____NZVC\n");
ot("\n");
if (high) ot(" ldrb r2,[r7,#0x44] ;@ Include SR high\n");
ot(" and r0,r0,#0x20000000\n");
ot(" orr r1,r1,r0,lsr #25 ;@ ___XNZVC\n");
if (high) ot(" orr r1,r1,r2,lsl #8\n");
ot("\n");
}
// Convert SR/CRR register in r0 to our flags
// trashes r0,r1
void OpRegToFlags(int high, int srh_reg)
{
ot(" eor r1,r0,r0,ror #1 ;@ Bit 0=C^V\n");
ot(" mov r2,r0,lsl #25\n");
ot(" tst r1,#1 ;@ 1 if C!=V\n");
ot(" eorne r0,r0,#3 ;@ ___XNZCV\n");
ot(" str r2,[r7,#0x4c] ;@ Store X bit\n");
ot(" mov r10,r0,lsl #28 ;@ r10=NZCV...\n");
if (high)
{
int mask=EMULATE_TRACE?0xa7:0x27;
ot(" mov r%i,r0,ror #8\n",srh_reg);
ot(" and r%i,r%i,#0x%02x ;@ only take defined bits\n",srh_reg,srh_reg,mask);
ot(" strb r%i,[r7,#0x44] ;@ Store SR high\n",srh_reg);
}
ot("\n");
}
void SuperEnd(void)
{
ot(";@ ----------\n");
ot(";@ tried execute privileged instruction in user mode\n");
ot("WrongPrivilegeMode%s\n",ms?"":":");
#if EMULATE_ADDRESS_ERRORS_JUMP || EMULATE_ADDRESS_ERRORS_IO
ot(" ldr r1,[r7,#0x58]\n");
ot(" sub r4,r4,#2 ;@ last opcode wasn't executed - go back\n");
ot(" orr r1,r1,#4 ;@ set activity bit: 'not processing instruction'\n");
ot(" str r1,[r7,#0x58]\n");
#else
ot(" sub r4,r4,#2 ;@ last opcode wasn't executed - go back\n");
#endif
ot(" mov r0,#8 ;@ privilege violation\n");
ot(" bl Exception\n");
Cycles=34;
OpEnd(0);
}
// does OSP and A7 swapping if needed
// new or old SR (not the one already in [r7,#0x44]) should be passed in r11
// uses srh from srh_reg (loads if < 0), trashes r0,r11
void SuperChange(int op,int srh_reg)
{
ot(";@ A7 <-> OSP?\n");
if (srh_reg < 0) {
ot(" ldr r0,[r7,#0x44] ;@ Get other SR high\n");
srh_reg=0;
}
ot(" eor r0,r%i,r11\n",srh_reg);
ot(" tst r0,#0x20\n");
ot(" beq no_sp_swap%.4x\n",op);
ot(" ;@ swap OSP and A7:\n");
ot(" ldr r11,[r7,#0x3C] ;@ Get A7\n");
ot(" ldr r0, [r7,#0x48] ;@ Get OSP\n");
ot(" str r11,[r7,#0x48]\n");
ot(" str r0, [r7,#0x3C]\n");
ot("no_sp_swap%.4x%s\n", op, ms?"":":");
}
// --------------------- Opcodes 0x1000+ ---------------------
// Emit a Move opcode, 00xxdddd ddssssss
int OpMove(int op)
{
int sea=0,tea=0;
int size=0,use=0;
int movea=0;
// Get source and target EA
sea = op&0x003f;
tea =(op&0x01c0)>>3;
tea|=(op&0x0e00)>>9;
if (tea>=8 && tea<0x10) movea=1;
// Find size extension
switch (op&0x3000)
{
default: return 1;
case 0x1000: size=0; break;
case 0x3000: size=1; break;
case 0x2000: size=2; break;
}
if (size<1 && (movea || EaAn(sea))) return 1; // move.b An,* and movea.b * are invalid
// See if we can do this opcode:
if (EaCanRead (sea,size)==0) return 1;
if (EaCanWrite(tea )==0) return 1;
use=OpBase(op,size);
if (tea<0x38) use&=~0x0e00; // Use same handler for register ?0-7
if (tea==0x1f || tea==0x27) use|=0x0e00; // Specific handler for (a7)+ and -(a7)
if (op!=use) { OpUse(op,use); return 0; } // Use existing handler
OpStart(op,sea,tea); Cycles=4;
if (movea==0)
{
EaCalcRead(-1,0,sea,size,0x003f);
ot(" adds r1,r0,#0 ;@ Defines NZ, clears CV\n");
ot(" mrs r10,cpsr ;@ r10=NZCV flags\n");
ot("\n");
}
else
{
EaCalcRead(-1,1,sea,size,0x003f);
size=2; // movea always expands to 32-bits
}
eawrite_check_addrerr=1;
#if SPLIT_MOVEL_PD
if ((tea&0x38)==0x20 && size==2) { // -(An)
EaCalc (8,0x0e00,tea,size,0,0);
ot(" mov r11,r1\n");
ot(" add r0,r8,#2\n");
EaWrite(0, 1,tea,1,0x0e00,0,0);
EaWrite(8, 11,tea,1,0x0e00,1);
}
else
#endif
{
EaCalc (0,0x0e00,tea,size,0,0);
EaWrite(0, 1,tea,size,0x0e00,0,0);
}
#if CYCLONE_FOR_GENESIS && !MEMHANDLERS_CHANGE_CYCLES
// this is a bit hacky (device handlers might modify cycles)
if (tea==0x39||((0x10<=tea&&tea<0x30)&&size>=1))
ot(" ldr r5,[r7,#0x5c] ;@ Load Cycles\n");
#endif
if((tea&0x38)==0x20) Cycles-=2; // less cycles when dest is -(An)
OpEnd(sea,tea);
return 0;
}
// --------------------- Opcodes 0x41c0+ ---------------------
// Emit an Lea opcode, 0100nnn1 11aaaaaa
int OpLea(int op)
{
int use=0;
int sea=0,tea=0;
sea= op&0x003f;
tea=(op&0x0e00)>>9; tea|=8;
if (EaCanRead(sea,-1)==0) return 1; // See if we can do this opcode
use=OpBase(op,0);
use&=~0x0e00; // Also use 1 handler for target ?0-7
if (op!=use) { OpUse(op,use); return 0; } // Use existing handler
OpStart(op,sea,tea);
eawrite_check_addrerr=1;
EaCalc (1,0x003f,sea,0); // Lea
EaCalc (0,0x0e00,tea,2);
EaWrite(0, 1,tea,2,0x0e00);
Cycles=Ea_add_ns(g_lea_cycle_table,sea);
OpEnd(sea,tea);
return 0;
}
// --------------------- Opcodes 0x40c0+ ---------------------
// Move SR opcode, 01000tt0 11aaaaaa move SR
int OpMoveSr(int op)
{
int type=0,ea=0;
int use=0,size=1;
type=(op>>9)&3; // from SR, from CCR, to CCR, to SR
ea=op&0x3f;
if(EaAn(ea)) return 1; // can't use An regs
switch(type)
{
case 0:
if (EaCanWrite(ea)==0) return 1; // See if we can do this opcode:
break;
case 1:
return 1; // no such op in 68000
case 2: case 3:
if (EaCanRead(ea,size)==0) return 1; // See if we can do this opcode:
break;
}
use=OpBase(op,size);
if (op!=use) { OpUse(op,use); return 0; } // Use existing handler
// 68000 model allows reading whole SR in user mode (but newer models don't)
OpStart(op,ea,0,0,type==3);
Cycles=12;
if (type==0) Cycles=(ea>=8)?8:6;
if (type==0 || type==1)
{
eawrite_check_addrerr=1;
OpFlagsToReg(type==0);
EaCalc (0,0x003f,ea,size,0,0);
EaWrite(0, 1,ea,size,0x003f,0,0);
}
if (type==2 || type==3)
{
EaCalcReadNoSE(-1,0,ea,size,0x003f);
OpRegToFlags(type==3,1);
if (type==3) {
SuperChange(op,1);
opend_check_interrupt = 1;
opend_check_trace = 1;
OpEnd(ea);
return 0;
}
}
OpEnd(ea);
return 0;
}
// Ori/Andi/Eori $nnnn,sr 0000t0t0 01111100
int OpArithSr(int op)
{
int type=0,ea=0;
int use=0,size=0;
int sr_mask=EMULATE_TRACE?0xa7:0x27;
type=(op>>9)&5; if (type==4) return 1;
size=(op>>6)&1; // ccr or sr?
ea=0x3c;
use=OpBase(op,size);
if (op!=use) { OpUse(op,use); return 0; } // Use existing handler
OpStart(op,ea,0,0,size!=0); Cycles=16;
EaCalcRead(-1,0,ea,size,0x003f);
ot(" eor r1,r0,r0,ror #1 ;@ Bit 0=C^V\n");
ot(" tst r1,#1 ;@ 1 if C!=V\n");
ot(" eorne r0,r0,#3 ;@ ___XNZCV\n");
ot(" ldr r2,[r7,#0x4c] ;@ Load old X bit\n");
// note: old srh is already in r11 (done by OpStart)
if (type==0) {
ot(" orr r10,r10,r0,lsl #28\n");
ot(" orr r2,r2,r0,lsl #25 ;@ X bit\n");
if (size!=0) {
ot(" orr r1,r11,r0,lsr #8\n");
ot(" and r1,r1,#0x%02x ;@ mask-out unused bits\n",sr_mask);
}
}
if (type==1) {
ot(" and r10,r10,r0,lsl #28\n");
ot(" and r2,r2,r0,lsl #25 ;@ X bit\n");
if (size!=0)
ot(" and r1,r11,r0,lsr #8\n");
}
if (type==5) {
ot(" eor r10,r10,r0,lsl #28\n");
ot(" eor r2,r2,r0,lsl #25 ;@ X bit\n");
if (size!=0) {
ot(" eor r1,r11,r0,lsr #8\n");
ot(" and r1,r1,#0x%02x ;@ mask-out unused bits\n",sr_mask);
}
}
ot(" str r2,[r7,#0x4c] ;@ Save X bit\n");
if (size!=0)
ot(" strb r1,[r7,#0x44]\n");
ot("\n");
// we can't enter supervisor mode, nor unmask irqs just by using OR
if (size!=0 && type!=0) {
SuperChange(op,1);
ot("\n");
opend_check_interrupt = 1;
}
// also can't set trace bit with AND
if (size!=0 && type!=1)
opend_check_trace = 1;
OpEnd(ea);
return 0;
}
// --------------------- Opcodes 0x4850+ ---------------------
// Emit an Pea opcode, 01001000 01aaaaaa
int OpPea(int op)
{
int use=0;
int ea=0;
ea=op&0x003f; if (ea<0x10) return 1; // Swap opcode
if (EaCanRead(ea,-1)==0) return 1; // See if we can do this opcode:
use=OpBase(op,0);
if (op!=use) { OpUse(op,use); return 0; } // Use existing handler
OpStart(op,ea);
ot(" ldr r11,[r7,#0x3c]\n");
EaCalc (1,0x003f, ea,0);
ot("\n");
ot(" sub r0,r11,#4 ;@ Predecrement A7\n");
ot(" str r0,[r7,#0x3c] ;@ Save A7\n");
ot("\n");
MemHandler(1,2); // Write 32-bit
ot("\n");
Cycles=6+Ea_add_ns(g_pea_cycle_table,ea);
OpEnd(ea);
return 0;
}
// --------------------- Opcodes 0x4880+ ---------------------
// Emit a Movem opcode, 01001d00 1xeeeeee regmask
int OpMovem(int op)
{
int size=0,ea=0,cea=0,dir=0;
int use=0,decr=0,change=0;
size=((op>>6)&1)+1; // word, long
ea=op&0x003f;
dir=(op>>10)&1; // Direction (1==ea2reg)
if (dir) {
if (ea<0x10 || ea>0x3b || (ea&0x38)==0x20) return 1; // Invalid EA
} else {
if (ea<0x10 || ea>0x39 || (ea&0x38)==0x18) return 1;
}
if ((ea&0x38)==0x18 || (ea&0x38)==0x20) change=1;
if ((ea&0x38)==0x20) decr=1; // -(An), bitfield is decr
cea=ea; if (change) cea=0x10;
use=OpBase(op,size);
if (op!=use) { OpUse(op,use); return 0; } // Use existing handler
OpStart(op,ea,0,1);
ot(" ldrh r11,[r4],#2 ;@ r11=register mask\n");
ot("\n");
ot(";@ Get the address into r6:\n");
EaCalc(6,0x003f,cea,size);
#if !MEMHANDLERS_NEED_PREV_PC
// must save PC, need a spare register
ot(" str r4,[r7,#0x40] ;@ Save PC\n");
#endif
ot(";@ r4=Register Index*4:\n");
if (decr) ot(" mov r4,#0x40 ;@ order reversed for -(An)\n");
else ot(" mov r4,#-4\n");
ot("\n");
ot(" tst r11,r11\n"); // sanity check
ot(" beq NoRegs%.4x\n",op);
#if EMULATE_ADDRESS_ERRORS_IO
ot("\n");
ot(" tst r6,#1 ;@ address error?\n");
ot(" movne r0,r6\n");
ot(" bne ExceptionAddressError_%c_data\n",dir?'r':'w');
#endif
ot("\n");
ot("Movemloop%.4x%s\n",op, ms?"":":");
ot(" add r4,r4,#%d ;@ r4=Next Register\n",decr?-4:4);
ot(" movs r11,r11,lsr #1\n");
ot(" bcc Movemloop%.4x\n",op);
ot("\n");
if (decr) ot(" sub r6,r6,#%d ;@ Pre-decrement address\n",1<<size);
if (dir)
{
ot(" ;@ Copy memory to register:\n",1<<size);
earead_check_addrerr=0; // already checked
EaRead (6,0,ea,size,0x003f);
ot(" str r0,[r7,r4] ;@ Save value into Dn/An\n");
}
else
{
ot(" ;@ Copy register to memory:\n",1<<size);
ot(" ldr r1,[r7,r4] ;@ Load value from Dn/An\n");
#if SPLIT_MOVEL_PD
if (decr && size==2) { // -(An)
ot(" add r0,r6,#2\n");
EaWrite(0,1,ea,1,0x003f,0,0);
ot(" ldr r1,[r7,r4] ;@ Load value from Dn/An\n");
ot(" mov r0,r6\n");
EaWrite(0,1,ea,1,0x003f,1);
}
else
#endif
{
EaWrite(6,1,ea,size,0x003f);
}
}
if (decr==0) ot(" add r6,r6,#%d ;@ Post-increment address\n",1<<size);
ot(" sub r5,r5,#%d ;@ Take some cycles\n",2<<size);
ot(" tst r11,r11\n");
ot(" bne Movemloop%.4x\n",op);
ot("\n");
if (change)
{
ot(";@ Write back address:\n");
EaCalc (0,0x0007,8|(ea&7),2);
EaWrite(0, 6,8|(ea&7),2,0x0007);
}
ot("NoRegs%.4x%s\n",op, ms?"":":");
ot(" ldr r4,[r7,#0x40]\n");
ot(" ldr r6,[r7,#0x54] ;@ restore Opcode Jump table\n");
ot("\n");
if(dir) { // er
if (ea==0x3a) Cycles=16; // ($nn,PC)
else if (ea==0x3b) Cycles=18; // ($nn,pc,Rn)
else Cycles=12;
} else {
Cycles=8;
}
Cycles+=Ea_add_ns(g_movem_cycle_table,ea);
opend_op_changes_cycles = 1;
OpEnd(ea);
ot("\n");
return 0;
}
// --------------------- Opcodes 0x4e60+ ---------------------
// Emit a Move USP opcode, 01001110 0110dnnn move An to/from USP
int OpMoveUsp(int op)
{
int use=0,dir=0;
dir=(op>>3)&1; // Direction
use=op&~0x0007; // Use same opcode for all An
if (op!=use) { OpUse(op,use); return 0; } // Use existing handler
OpStart(op,0,0,0,1); Cycles=4;
if (dir)
{
eawrite_check_addrerr=1;
ot(" ldr r1,[r7,#0x48] ;@ Get from USP\n\n");
EaCalc (0,0x000f,8,2,1);
EaWrite(0, 1,8,2,0x000f,1);
}
else
{
EaCalc (0,0x000f,8,2,1);
EaRead (0, 0,8,2,0x000f,1);
ot(" str r0,[r7,#0x48] ;@ Put in USP\n\n");
}
OpEnd();
return 0;
}
// --------------------- Opcodes 0x7000+ ---------------------
// Emit a Move Quick opcode, 0111nnn0 dddddddd moveq #dd,Dn
int OpMoveq(int op)
{
int use=0;
use=op&0xf100; // Use same opcode for all values
if (op!=use) { OpUse(op,use); return 0; } // Use existing handler
OpStart(op); Cycles=4;
ot(" movs r0,r8,asl #24\n");
ot(" and r1,r8,#0x0e00\n");
ot(" mov r0,r0,asr #24 ;@ Sign extended Quick value\n");
ot(" mrs r10,cpsr ;@ r10=NZ flags\n");
ot(" str r0,[r7,r1,lsr #7] ;@ Store into Dn\n");
ot("\n");
OpEnd();
return 0;
}
// --------------------- Opcodes 0xc140+ ---------------------
// Emit a Exchange opcode:
// 1100ttt1 01000sss exg ds,dt
// 1100ttt1 01001sss exg as,at
// 1100ttt1 10001sss exg as,dt
int OpExg(int op)
{
int use=0,type=0;
type=op&0xf8;
if (type!=0x40 && type!=0x48 && type!=0x88) return 1; // Not an exg opcode
use=op&0xf1f8; // Use same opcode for all values
if (op!=use) { OpUse(op,use); return 0; } // Use existing handler
OpStart(op); Cycles=6;
ot(" and r2,r8,#0x0e00 ;@ Find T register\n");
ot(" and r3,r8,#0x000f ;@ Find S register\n");
if (type==0x48) ot(" orr r2,r2,#0x1000 ;@ T is an address register\n");
ot("\n");
ot(" ldr r0,[r7,r2,lsr #7] ;@ Get T\n");
ot(" ldr r1,[r7,r3,lsl #2] ;@ Get S\n");
ot("\n");
ot(" str r0,[r7,r3,lsl #2] ;@ T->S\n");
ot(" str r1,[r7,r2,lsr #7] ;@ S->T\n");
ot("\n");
OpEnd();
return 0;
}
// ------------------------- movep -------------------------------
// 0000ddd1 0z001sss
// 0000sss1 1z001ddd (to mem)
int OpMovep(int op)
{
int ea=0,rea=0;
int size=1,use=0,dir,aadd=0;
use=op&0xf1f8;
if (op!=use) { OpUse(op,use); return 0; } // Use existing handler (for all dests, srcs)
// Get EA
ea = (op&0x0007)|0x28;
rea= (op&0x0e00)>>9;
dir = (op>>7)&1;
// Find size extension
if(op&0x0040) size=2;
OpStart(op,ea);
if(dir) // reg to mem
{
EaCalcReadNoSE(-1,11,rea,size,0x0e00);
EaCalc(8,0x000f,ea,size);
if(size==2) { // if operand is long
ot(" mov r1,r11,lsr #24 ;@ first byte\n");
EaWrite(8,1,ea,0,0x000f); // store first byte
ot(" add r0,r8,#%i\n",(aadd+=2));
ot(" mov r1,r11,lsr #16 ;@ second byte\n");
EaWrite(0,1,ea,0,0x000f); // store second byte
ot(" add r0,r8,#%i\n",(aadd+=2));
} else {
ot(" mov r0,r8\n");
}
ot(" mov r1,r11,lsr #8 ;@ first or third byte\n");
EaWrite(0,1,ea,0,0x000f);
ot(" add r0,r8,#%i\n",(aadd+=2));
ot(" and r1,r11,#0xff\n");
EaWrite(0,1,ea,0,0x000f);
}
else // mem to reg
{
EaCalc(6,0x000f,ea,size,1);
EaRead(6,11,ea,0,0x000f,1); // read first byte
ot(" add r0,r6,#2\n");
EaRead(0,1,ea,0,0x000f,1); // read second byte
if(size==2) { // if operand is long
ot(" orr r11,r11,r1,lsr #8 ;@ second byte\n");
ot(" add r0,r6,#4\n");
EaRead(0,1,ea,0,0x000f,1);
ot(" orr r11,r11,r1,lsr #16 ;@ third byte\n");
ot(" add r0,r6,#6\n");
EaRead(0,1,ea,0,0x000f,1);
ot(" orr r1,r11,r1,lsr #24 ;@ fourth byte\n");
} else {
ot(" orr r1,r11,r1,lsr #8 ;@ second byte\n");
}
// store the result
EaCalc(0,0x0e00,rea,size,1);
EaWrite(0,1,rea,size,0x0e00,1);
ot(" ldr r6,[r7,#0x54]\n");
}
Cycles=(size==2)?24:16;
OpEnd(ea);
return 0;
}
// Emit a Stop/Reset opcodes, 01001110 011100t0 imm
int OpStopReset(int op)
{
int type=(op>>1)&1; // stop/reset
OpStart(op,0,0,0,1);
if(type) {
// copy immediate to SR, stop the CPU and eat all remaining cycles.
ot(" ldrh r0,[r4],#2 ;@ Fetch the immediate\n");
OpRegToFlags(1);
SuperChange(op,0);
ot("\n");
ot(" ldr r0,[r7,#0x58]\n");
ot(" mov r5,#0 ;@ eat cycles\n");
ot(" orr r0,r0,#1 ;@ stopped\n");
ot(" str r0,[r7,#0x58]\n");
ot("\n");
Cycles = 4;
ot("\n");
}
else
{
Cycles = 132;
#if USE_RESET_CALLBACK
ot(" str r4,[r7,#0x40] ;@ Save PC\n");
ot(" mov r1,r10,lsr #28\n");
ot(" strb r1,[r7,#0x46] ;@ Save Flags (NZCV)\n");
ot(" str r5,[r7,#0x5c] ;@ Save Cycles\n");
ot(" ldr r11,[r7,#0x90] ;@ ResetCallback\n");
ot(" tst r11,r11\n");
ot(" movne lr,pc\n");
ot(" bxne r11 ;@ call ResetCallback if it is defined\n");
ot(" ldrb r10,[r7,#0x46] ;@ r10 = Load Flags (NZCV)\n");
ot(" ldr r5,[r7,#0x5c] ;@ Load Cycles\n");
ot(" ldr r4,[r7,#0x40] ;@ Load PC\n");
ot(" mov r10,r10,lsl #28\n");
ot("\n");
#endif
}
OpEnd();
return 0;
}