From e4426dc952c4845adeb47756a53fc5ca60e17441 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Fri, 29 Apr 2022 20:30:48 -0400
Subject: [PATCH 1/2] Introduce calculate EA steps.
---
.../Implementation/PerformImplementation.hpp | 4 ++--
InstructionSets/M68k/Sequence.cpp | 7 ++++---
InstructionSets/M68k/Sequence.hpp | 17 ++++++++++++-----
3 files changed, 18 insertions(+), 10 deletions(-)
diff --git a/InstructionSets/M68k/Implementation/PerformImplementation.hpp b/InstructionSets/M68k/Implementation/PerformImplementation.hpp
index 2dad77da5..c4f450c85 100644
--- a/InstructionSets/M68k/Implementation/PerformImplementation.hpp
+++ b/InstructionSets/M68k/Implementation/PerformImplementation.hpp
@@ -399,7 +399,7 @@ template <
// JMP: copies EA(0) to the program counter.
case Operation::JMP:
- flow_controller.set_pc(flow_controller.effective_address(0));
+ flow_controller.set_pc(src.l);
break;
/*
@@ -438,7 +438,7 @@ template <
break;
case Operation::LEA:
- dest.l = flow_controller.effective_address(0);
+ dest.l = src.l;
break;
// case Operation::PEA:
diff --git a/InstructionSets/M68k/Sequence.cpp b/InstructionSets/M68k/Sequence.cpp
index dc45925bd..07ec25bb4 100644
--- a/InstructionSets/M68k/Sequence.cpp
+++ b/InstructionSets/M68k/Sequence.cpp
@@ -11,14 +11,14 @@
using namespace InstructionSet::M68k;
template <Step... T> struct Steps {
- static constexpr uint16_t value = 0;
+ static constexpr uint32_t value = 0;
};
template <Step F, Step... T> struct Steps<F, T...> {
- static constexpr uint16_t value = uint16_t(F) | uint16_t(Steps<T...>::value << 3);
+ static constexpr uint32_t value = uint16_t(F) | uint16_t(Steps<T...>::value << 4);
};
-template<Model model> uint16_t Sequence<model>::steps_for(Operation operation) {
+template<Model model> uint32_t Sequence<model>::steps_for(Operation operation) {
switch(operation) {
// This handles a NOP, and not much else.
default: return 0;
@@ -28,6 +28,7 @@ template<Model model> uint16_t Sequence<model>::steps_for(Operation operation) {
//
case Operation::LEA:
return Steps<
+ Step::CalcEA1,
Step::Perform
>::value;
diff --git a/InstructionSets/M68k/Sequence.hpp b/InstructionSets/M68k/Sequence.hpp
index 2e13afc8d..7c1c4a328 100644
--- a/InstructionSets/M68k/Sequence.hpp
+++ b/InstructionSets/M68k/Sequence.hpp
@@ -35,6 +35,12 @@ enum class Step {
StoreOp1,
/// Store the value of operand 2.
StoreOp2,
+ /// Calculate effective address of operand 1.
+ CalcEA1,
+ /// Calculate effective address of operand 2.
+ CalcEA2,
+
+ Max = CalcEA2
};
/// Indicates the abstract steps necessary to perform an operation,
@@ -47,8 +53,9 @@ template<Model model> class Sequence {
/// if no further steps remain. This step is removed from the
/// list of remaining steps.
Step pop_front() {
- const auto step = Step(steps_ & 7);
- steps_ >>= 3;
+ static_assert(int(Step::Max) < 16);
+ const auto step = Step(steps_ & 15);
+ steps_ >>= 4;
return step;
}
@@ -59,12 +66,12 @@ template<Model model> class Sequence {
}
private:
- uint16_t steps_ = 0;
+ uint32_t steps_ = 0;
- uint16_t steps_for(Operation);
+ uint32_t steps_for(Operation);
};
-static_assert(sizeof(Sequence<Model::M68000>) == sizeof(uint16_t));
+static_assert(sizeof(Sequence<Model::M68000>) == sizeof(uint32_t));
}
}
From f4074e0bba899c9b8151efa81b4363f26e2536c3 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Sat, 30 Apr 2022 08:38:28 -0400
Subject: [PATCH 2/2] Add basic status.
---
InstructionSets/M68k/Executor.hpp | 2 ++
1 file changed, 2 insertions(+)
diff --git a/InstructionSets/M68k/Executor.hpp b/InstructionSets/M68k/Executor.hpp
index a51af6fce..b9a28ebec 100644
--- a/InstructionSets/M68k/Executor.hpp
+++ b/InstructionSets/M68k/Executor.hpp
@@ -46,6 +46,8 @@ template <Model model, typename BusHandler> class Executor {
// Processor state.
Status status_;
CPU::SlicedInt32 program_counter_;
+ CPU::SlicedInt32 data_[8], address_[8];
+ CPU::SlicedInt32 stack_pointers_[2];
};
}