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Merge pull request #1057 from TomHarte/ContinuousLabels

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68000: Eliminate large gap in `case` values.
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Thomas Harte 2022-06-29 21:48:44 -04:00 committed by GitHub
commit 970087eefb
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2 changed files with 7 additions and 5 deletions
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10
Processors/68000Mk2/Implementation/68000Mk2Implementation.hpp
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@ -24,7 +24,7 @@ namespace MC68000Mk2 {
/// me for their purpose rather than automatically by file position.
/// These are negative to avoid ambiguity with the other group.
enum ExecutionState: int {
Reset = std::numeric_limits<int>::min(),
Reset,
Decode,
WaitForDTACK,
WaitForInterrupt,
@ -189,6 +189,8 @@ enum ExecutionState: int {
MOVE_b, MOVE_w,
AddressingDispatch(MOVE_bw), MOVE_bw_AbsoluteLong_prefetch_first,
AddressingDispatch(MOVE_l), MOVE_l_AbsoluteLong_prefetch_first,
Max
};
#undef AddressingDispatch
@ -214,7 +216,7 @@ void Processor<BusHandler, dtack_is_implicit, permit_overrun, signal_will_perfor
// Check whether all remaining time has been expended; if so then exit, having set this line up as
// the next resumption point.
#define ConsiderExit() if(time_remaining_ < HalfCycles(0)) { state_ = __COUNTER__+1; return; } [[fallthrough]]; case __COUNTER__:
#define ConsiderExit() if(time_remaining_ < HalfCycles(0)) { state_ = ExecutionState::Max+__COUNTER__+1; return; } [[fallthrough]]; case ExecutionState::Max+__COUNTER__:
// Subtracts `n` half-cycles from `time_remaining_`; if permit_overrun is false, also ConsiderExit()
#define Spend(n) time_remaining_ -= (n); if constexpr (!permit_overrun) ConsiderExit()
@ -296,11 +298,11 @@ void Processor<BusHandler, dtack_is_implicit, permit_overrun, signal_will_perfor
if constexpr (!dtack_is_implicit && !dtack_ && !vpa_ && !berr_) { \
awaiting_dtack = x; \
awaiting_dtack.length = HalfCycles(2); \
post_dtack_state_ = __COUNTER__+1; \
post_dtack_state_ = ExecutionState::Max+__COUNTER__+1; \
state_ = ExecutionState::WaitForDTACK; \
break; \
} \
[[fallthrough]]; case __COUNTER__:
[[fallthrough]]; case ExecutionState::Max+__COUNTER__:
// Performs the bus operation provided, which will be one with a
// SelectWord or SelectByte operation, stretching it to match the E

2
Processors/68000Mk2/Implementation/68000Mk2Storage.hpp
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@ -25,7 +25,7 @@ struct ProcessorBase: public InstructionSet::M68k::NullFlowController {
ProcessorBase(const ProcessorBase& rhs) = delete;
ProcessorBase& operator=(const ProcessorBase& rhs) = delete;
int state_ = std::numeric_limits<int>::min();
int state_ = 0;
/// Counts time left on the clock before the current batch of processing
/// is complete; may be less than zero.