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Commute ROL/ROR to templates.

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This commit is contained in:
Thomas Harte 2022-10-16 12:19:09 -04:00
parent fee072b404
commit 17c1e51231
1 changed files with 44 additions and 44 deletions
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88
InstructionSets/M68k/Implementation/PerformImplementation.hpp
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@ -256,6 +256,42 @@ template <typename IntT> void set_neg_zero_overflow(IntT result, IntT destinatio
status.overflow_flag = Status::FlagT((destination ^ result) & top_bit<IntT>());
}
/// Perform a rotate without extend, i.e. any of RO[L/R].[b/w/l].
template <Operation operation, typename IntT, typename FlowController> void rotate(uint32_t source, IntT &destination, Status &status, FlowController &flow_controller) {
static_assert(
operation == Operation::ROLb || operation == Operation::ROLw || operation == Operation::ROLl ||
operation == Operation::RORb || operation == Operation::RORw || operation == Operation::RORl
);
const auto size = bit_size<IntT>();
const auto shift = shift_count<IntT>(uint8_t(source), flow_controller) & (size - 1);
IntT result;
if(!shift) {
result = destination;
status.carry_flag = 0;
} else {
switch(operation) {
case Operation::ROLb: case Operation::ROLw: case Operation::ROLl:
result = IntT(
(destination << shift) |
(destination >> (size - shift))
);
break;
case Operation::RORb: case Operation::RORw: case Operation::RORl:
result = IntT(
(destination >> shift) |
(destination << (size - shift))
);
break;
}
status.carry_flag = Status::FlagT(result & 1);
}
set_neg_zero_overflow(result, destination, status);
destination = IntT(result);
}
/// Perform a rotate-through-extend, i.e. any of ROX[L/R].[b/w/l].
template <Operation operation, typename IntT, typename FlowController> void rox(uint32_t source, IntT &destination, Status &status, FlowController &flow_controller) {
static_assert(
@ -862,51 +898,17 @@ template <
case Operation::LSRw: lsr(dest.w, 16); break;
case Operation::LSRl: lsr(dest.l, 32); break;
#define rol(destination, size) { \
decode_shift_count(decltype(destination)); \
const auto value = destination; \
\
if(!shift_count) { \
status.carry_flag = 0; \
} else { \
shift_count &= (size - 1); \
destination = decltype(destination)( \
(value << shift_count) | \
(value >> (size - shift_count)) \
); \
status.carry_flag = Status::FlagT(destination & 1); \
} \
\
set_neg_zero_overflow(destination, 1 << (size - 1)); \
}
// ---
case Operation::ROLm: {
const auto value = src.w;
src.w = uint16_t((value << 1) | (value >> 15));
status.carry_flag = src.w & 1;
status.carry_flag = src.w & 0x0001;
set_neg_zero_overflow(src.w, 0x8000);
} break;
case Operation::ROLb: rol(dest.b, 8); break;
case Operation::ROLw: rol(dest.w, 16); break;
case Operation::ROLl: rol(dest.l, 32); break;
#define ror(destination, size) { \
decode_shift_count(decltype(destination)); \
const auto value = destination; \
\
if(!shift_count) { \
status.carry_flag = 0; \
} else { \
shift_count &= (size - 1); \
destination = decltype(destination)(\
(value >> shift_count) | \
(value << (size - shift_count)) \
);\
status.carry_flag = destination & Status::FlagT(1 << (size - 1)); \
} \
\
set_neg_zero_overflow(destination, 1 << (size - 1)); \
}
case Operation::ROLb: Primitive::rotate<Operation::ROLb>(src.l, dest.b, status, flow_controller); break;
case Operation::ROLw: Primitive::rotate<Operation::ROLw>(src.l, dest.w, status, flow_controller); break;
case Operation::ROLl: Primitive::rotate<Operation::ROLl>(src.l, dest.l, status, flow_controller); break;
case Operation::RORm: {
const auto value = src.w;
@ -914,11 +916,9 @@ template <
status.carry_flag = src.w & 0x8000;
set_neg_zero_overflow(src.w, 0x8000);
} break;
case Operation::RORb: ror(dest.b, 8); break;
case Operation::RORw: ror(dest.w, 16); break;
case Operation::RORl: ror(dest.l, 32); break;
// ---
case Operation::RORb: Primitive::rotate<Operation::RORb>(src.l, dest.b, status, flow_controller); break;
case Operation::RORw: Primitive::rotate<Operation::RORw>(src.l, dest.w, status, flow_controller); break;
case Operation::RORl: Primitive::rotate<Operation::RORl>(src.l, dest.l, status, flow_controller); break;
case Operation::ROXLm: {
const auto value = src.w;