replace symlinks

Signed-off-by: Amneesh Singh <natto@weirdnatto.in>

include/cpu/instruction.hh

@@ -0,0 +1,132 @@
+#include "cpu/utility.hh"
+#include <cstdint>
+#include <variant>
+
+template<class... Ts>
+struct overloaded : Ts... {
+    using Ts::operator()...;
+};
+template<class... Ts>
+overloaded(Ts...) -> overloaded<Ts...>;
+
+class ArmInstruction {
+  public:
+    ArmInstruction() = delete;
+    ArmInstruction(uint32_t insn);
+
+    auto get_condition() const { return condition; }
+    auto get_data() const { return data; }
+
+    std::string disassemble();
+
+    struct BranchAndExchange {
+        uint8_t rn;
+    };
+
+    struct Branch {
+        bool link;
+        uint32_t offset;
+    };
+
+    struct Multiply {
+        uint8_t rm;
+        uint8_t rs;
+        uint8_t rn;
+        uint8_t rd;
+        bool set;
+        bool acc;
+    };
+
+    struct MultiplyLong {
+        uint8_t rm;
+        uint8_t rs;
+        uint8_t rdlo;
+        uint8_t rdhi;
+        bool set;
+        bool acc;
+        bool uns;
+    };
+
+    struct SingleDataSwap {
+        uint8_t rm;
+        uint8_t rd;
+        uint8_t rn;
+        bool byte;
+    };
+
+    struct SingleDataTransfer {
+        std::variant<uint16_t, Shift> offset;
+        uint8_t rd;
+        uint8_t rn;
+        bool load;
+        bool write;
+        bool byte;
+        bool up;
+        bool pre;
+    };
+
+    struct HalfwordTransfer {
+        uint8_t offset;
+        bool half;
+        bool sign;
+        uint8_t rd;
+        uint8_t rn;
+        bool load;
+        bool write;
+        bool byte;
+        bool imm;
+        bool up;
+        bool pre;
+    };
+
+    struct CoprocessorDataTransfer {
+        uint8_t offset;
+        uint8_t cpn;
+        uint8_t crd;
+        uint8_t rn;
+        bool load;
+        bool write;
+        bool len;
+        bool up;
+        bool pre;
+    };
+
+    struct CoprocessorDataOperation {
+        uint8_t crm;
+        uint8_t cp;
+        uint8_t cpn;
+        uint8_t crd;
+        uint8_t crn;
+        uint8_t cp_opc;
+    };
+
+    struct CoprocessorRegisterTransfer {
+        uint8_t crm;
+        uint8_t cp;
+        uint8_t cpn;
+        uint8_t rd;
+        uint8_t crn;
+        bool load;
+        uint8_t cp_opc;
+    };
+
+    struct Undefined {};
+    struct SoftwareInterrupt {};
+
+    using InstructionData = std::variant<BranchAndExchange,
+                                         Branch,
+                                         Multiply,
+                                         MultiplyLong,
+                                         SingleDataSwap,
+                                         SingleDataTransfer,
+                                         HalfwordTransfer,
+                                         CoprocessorDataTransfer,
+                                         CoprocessorDataOperation,
+                                         CoprocessorRegisterTransfer,
+                                         Undefined,
+                                         SoftwareInterrupt>;
+
+  private:
+    Condition condition;
+    InstructionData data;
+};