bsnes/higan/processor/arm7tdmi/instructions-arm.cpp

315 lines
9.0 KiB
C++

auto ARM7TDMI::armALU(uint4 mode, uint4 d, uint4 n, uint32 rm) -> void {
uint32 rn = r(n);
switch(mode) {
case 0: r(d) = BIT(rn & rm); break; //AND
case 1: r(d) = BIT(rn ^ rm); break; //EOR
case 2: r(d) = SUB(rn, rm, 1); break; //SUB
case 3: r(d) = SUB(rm, rn, 1); break; //RSB
case 4: r(d) = ADD(rn, rm, 0); break; //ADD
case 5: r(d) = ADD(rn, rm, cpsr().c); break; //ADC
case 6: r(d) = SUB(rn, rm, cpsr().c); break; //SBC
case 7: r(d) = SUB(rm, rn, cpsr().c); break; //RSC
case 8: BIT(rn & rm); break; //TST
case 9: BIT(rn ^ rm); break; //TEQ
case 10: SUB(rn, rm, 1); break; //CMP
case 11: ADD(rn, rm, 0); break; //CMN
case 12: r(d) = BIT(rn | rm); break; //ORR
case 13: r(d) = BIT(rm); break; //MOV
case 14: r(d) = BIT(rn & ~rm); break; //BIC
case 15: r(d) = BIT(~rm); break; //MVN
}
if(exception() && d == 15 && opcode.bit(20)) {
cpsr() = spsr();
}
}
auto ARM7TDMI::armMoveToStatus(uint4 field, uint1 mode, uint32 data) -> void {
if(mode && (cpsr().m == PSR::USR || cpsr().m == PSR::SYS)) return;
PSR& psr = mode ? spsr() : cpsr();
if(field.bit(0)) {
if(mode || privileged()) {
psr.m = data.bits(0,4);
psr.t = data.bit (5);
psr.f = data.bit (6);
psr.i = data.bit (7);
if(!mode && psr.t) r(15).data += 2;
}
}
if(field.bit(3)) {
psr.v = data.bit(28);
psr.c = data.bit(29);
psr.z = data.bit(30);
psr.n = data.bit(31);
}
}
//
auto ARM7TDMI::armInstructionBranch
(int24 displacement, uint1 link) -> void {
if(link) r(14) = r(15) - 4;
r(15) = r(15) + displacement * 4;
}
auto ARM7TDMI::armInstructionBranchExchangeRegister
(uint4 m) -> void {
uint32 address = r(m);
cpsr().t = address.bit(0);
r(15) = address;
}
auto ARM7TDMI::armInstructionDataImmediate
(uint8 immediate, uint4 shift, uint4 d, uint4 n, uint1 save, uint4 mode) -> void {
uint32 data = immediate;
carry = cpsr().c;
if(shift) data = ROR(data, shift << 1);
armALU(mode, d, n, data);
}
auto ARM7TDMI::armInstructionDataImmediateShift
(uint4 m, uint2 type, uint5 shift, uint4 d, uint4 n, uint1 save, uint4 mode) -> void {
uint32 rm = r(m);
carry = cpsr().c;
switch(type) {
case 0: rm = LSL(rm, shift); break;
case 1: rm = LSR(rm, shift ? (uint)shift : 32); break;
case 2: rm = ASR(rm, shift ? (uint)shift : 32); break;
case 3: rm = shift ? ROR(rm, shift) : RRX(rm); break;
}
armALU(mode, d, n, rm);
}
auto ARM7TDMI::armInstructionDataRegisterShift
(uint4 m, uint2 type, uint4 s, uint4 d, uint4 n, uint1 save, uint4 mode) -> void {
uint8 rs = r(s) + (s == 15 ? 4 : 0);
uint32 rm = r(m) + (m == 15 ? 4 : 0);
carry = cpsr().c;
switch(type) {
case 0: rm = LSL(rm, rs < 33 ? rs : (uint8)33); break;
case 1: rm = LSR(rm, rs < 33 ? rs : (uint8)33); break;
case 2: rm = ASR(rm, rs < 32 ? rs : (uint8)32); break;
case 3: if(rs) rm = ROR(rm, rs & 31 ? rs & 31 : 32); break;
}
armALU(mode, d, n, rm);
}
auto ARM7TDMI::armInstructionLoadImmediate
(uint8 immediate, uint1 half, uint4 d, uint4 n, uint1 writeback, uint1 up, uint1 pre) -> void {
uint32 rn = r(n);
uint32 rd = r(d);
if(pre == 1) rn = up ? rn + immediate : rn - immediate;
rd = load((half ? Half : Byte) | Nonsequential | Signed, rn);
if(pre == 0) rn = up ? rn + immediate : rn - immediate;
if(pre == 0 || writeback) r(n) = rn;
r(d) = rd;
}
auto ARM7TDMI::armInstructionLoadRegister
(uint4 m, uint1 half, uint4 d, uint4 n, uint1 writeback, uint1 up, uint1 pre) -> void {
uint32 rn = r(n);
uint32 rm = r(m);
uint32 rd = r(d);
if(pre == 1) rn = up ? rn + rm : rn - rm;
rd = load((half ? Half : Byte) | Nonsequential | Signed, rn);
if(pre == 0) rn = up ? rn + rm : rn - rm;
if(pre == 0 || writeback) r(n) = rn;
r(d) = rd;
}
auto ARM7TDMI::armInstructionMemorySwap
(uint4 m, uint4 d, uint4 n, uint1 byte) -> void {
uint32 word = load((byte ? Byte : Word) | Nonsequential, r(n));
store((byte ? Byte : Word) | Nonsequential, r(n), r(m));
r(d) = word;
}
auto ARM7TDMI::armInstructionMoveHalfImmediate
(uint8 immediate, uint4 d, uint4 n, uint1 mode, uint1 writeback, uint1 up, uint1 pre) -> void {
uint32 rn = r(n);
uint32 rd = r(d);
if(pre == 1) rn = up ? rn + immediate : rn - immediate;
if(mode == 1) rd = load(Half | Nonsequential, rn);
if(mode == 0) store(Half | Nonsequential, rn, rd);
if(pre == 0) rn = up ? rn + immediate : rn - immediate;
if(pre == 0 || writeback) r(n) = rn;
if(mode == 1) r(d) = rd;
}
auto ARM7TDMI::armInstructionMoveHalfRegister
(uint4 m, uint4 d, uint4 n, uint1 mode, uint1 writeback, uint1 up, uint1 pre) -> void {
uint32 rn = r(n);
uint32 rm = r(m);
uint32 rd = r(d);
if(pre == 1) rn = up ? rn + rm : rn - rm;
if(mode == 1) rd = load(Half | Nonsequential, rn);
if(mode == 0) store(Half | Nonsequential, rn, rd);
if(pre == 0) rn = up ? rn + rm : rn - rm;
if(pre == 0 || writeback) r(n) = rn;
if(mode == 1) r(d) = rd;
}
auto ARM7TDMI::armInstructionMoveImmediateOffset
(uint12 immediate, uint4 d, uint4 n, uint1 mode, uint1 writeback, uint1 byte, uint1 up, uint1 pre) -> void {
uint32 rn = r(n);
uint32 rd = r(d);
if(pre == 1) rn = up ? rn + immediate : rn - immediate;
if(mode == 1) rd = load((byte ? Byte : Word) | Nonsequential, rn);
if(mode == 0) store((byte ? Byte : Word) | Nonsequential, rn, rd);
if(pre == 0) rn = up ? rn + immediate : rn - immediate;
if(pre == 0 || writeback) r(n) = rn;
if(mode == 1) r(d) = rd;
}
auto ARM7TDMI::armInstructionMoveMultiple
(uint16 list, uint4 n, uint1 mode, uint1 writeback, uint1 type, uint1 up, uint1 pre) -> void {
uint32 rn = r(n);
if(pre == 0 && up == 1) rn = rn + 0; //IA
if(pre == 1 && up == 1) rn = rn + 4; //IB
if(pre == 1 && up == 0) rn = rn - bit::count(list) * 4 + 0; //DB
if(pre == 0 && up == 0) rn = rn - bit::count(list) * 4 + 4; //DA
if(writeback && mode == 1) {
if(up == 1) r(n) = r(n) + bit::count(list) * 4; //IA,IB
if(up == 0) r(n) = r(n) - bit::count(list) * 4; //DA,DB
}
auto cpsrMode = cpsr().m;
bool usr = false;
if(type && mode == 1 && !list.bit(15)) usr = true;
if(type && mode == 0) usr = true;
if(usr) cpsr().m = PSR::USR;
uint sequential = Nonsequential;
for(uint m : range(16)) {
if(!list.bit(m)) continue;
if(mode == 1) r(m) = read(Word | sequential, rn);
if(mode == 0) write(Word | sequential, rn, r(m));
rn += 4;
sequential = Sequential;
}
if(usr) cpsr().m = cpsrMode;
if(mode) {
idle();
if(type && list.bit(15) && cpsr().m != PSR::USR && cpsr().m != PSR::SYS) {
cpsr() = spsr();
}
} else {
pipeline.nonsequential = true;
}
if(writeback && mode == 0) {
if(up == 1) r(n) = r(n) + bit::count(list) * 4; //IA,IB
if(up == 0) r(n) = r(n) - bit::count(list) * 4; //DA,DB
}
}
auto ARM7TDMI::armInstructionMoveRegisterOffset
(uint4 m, uint2 type, uint5 shift, uint4 d, uint4 n, uint1 mode, uint1 writeback, uint1 byte, uint1 up, uint1 pre) -> void {
uint32 rm = r(m);
uint32 rd = r(d);
uint32 rn = r(n);
carry = cpsr().c;
switch(type) {
case 0: rm = LSL(rm, shift); break;
case 1: rm = LSR(rm, shift ? (uint)shift : 32); break;
case 2: rm = ASR(rm, shift ? (uint)shift : 32); break;
case 3: rm = shift ? ROR(rm, shift) : RRX(rm); break;
}
if(pre == 1) rn = up ? rn + rm : rn - rm;
if(mode == 1) rd = load((byte ? Byte : Word) | Nonsequential, rn);
if(mode == 0) store((byte ? Byte : Word) | Nonsequential, rn, rd);
if(pre == 0) rn = up ? rn + rm : rn - rm;
if(pre == 0 || writeback) r(n) = rn;
if(mode == 1) r(d) = rd;
}
auto ARM7TDMI::armInstructionMoveToRegisterFromStatus
(uint4 d, uint1 mode) -> void {
if(mode && (cpsr().m == PSR::USR || cpsr().m == PSR::SYS)) return;
r(d) = mode ? spsr() : cpsr();
}
auto ARM7TDMI::armInstructionMoveToStatusFromImmediate
(uint8 immediate, uint4 rotate, uint4 field, uint1 mode) -> void {
uint32 data = immediate;
if(rotate) data = ROR(data, rotate << 1);
armMoveToStatus(field, mode, data);
}
auto ARM7TDMI::armInstructionMoveToStatusFromRegister
(uint4 m, uint4 field, uint1 mode) -> void {
armMoveToStatus(field, mode, r(m));
}
auto ARM7TDMI::armInstructionMultiply
(uint4 m, uint4 s, uint4 n, uint4 d, uint1 save, uint1 accumulate) -> void {
if(accumulate) idle();
r(d) = MUL(accumulate ? r(n) : 0, r(m), r(s));
}
auto ARM7TDMI::armInstructionMultiplyLong
(uint4 m, uint4 s, uint4 l, uint4 h, uint1 save, uint1 accumulate, uint1 sign) -> void {
uint64 rm = r(m);
uint64 rs = r(s);
idle();
idle();
if(accumulate) idle();
if(sign) {
if(rs >> 8 && rs >> 8 != 0xffffff) idle();
if(rs >> 16 && rs >> 16 != 0xffff) idle();
if(rs >> 24 && rs >> 24 != 0xff) idle();
rm = (int32)rm;
rs = (int32)rs;
} else {
if(rs >> 8) idle();
if(rs >> 16) idle();
if(rs >> 24) idle();
}
uint64 rd = rm * rs;
if(accumulate) rd += (uint64)r(h) << 32 | (uint64)r(l) << 0;
r(h) = rd >> 32;
r(l) = rd >> 0;
if(save) {
cpsr().z = rd == 0;
cpsr().n = rd.bit(63);
}
}
auto ARM7TDMI::armInstructionSoftwareInterrupt
(uint24 immediate) -> void {
exception(PSR::SVC, 0x08);
}
auto ARM7TDMI::armInstructionUndefined
() -> void {
exception(PSR::UND, 0x04);
}