massive instruction rewrite

So, I ended up moving exec methods from Instruction to Cpu for
encapsulating cycle emulation, and this has caused me lots of pain since
I had to rewrite a shit ton of tests which are not even useful or
comprehensible, i do no know why i put myself through this

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

include/cpu/cpu.hh

@@ -19,11 +19,14 @@ class GdbRsp;
 
 class Cpu {
   public:
-    Cpu(std::shared_ptr<Bus>) noexcept;
+    Cpu(std::shared_ptr<Bus> bus) noexcept;
 
     void step();
     void chg_mode(const Mode to);
 
+    void exec(arm::Instruction& instruction);
+    void exec(thumb::Instruction& instruction);
+
 #ifdef GDB_DEBUG
     bool breakpoint_reached() {
         if (breakpoints.contains(pc - 2 * (cpsr.state() == State::Arm
@@ -92,10 +95,9 @@ class Cpu {
     // raw instructions in the pipeline
     std::array<uint32_t, 2> opcodes = {};
 
-    void advance_pc_arm() { pc += arm::INSTRUCTION_SIZE; };
-    void advance_pc_thumb() { pc += thumb::INSTRUCTION_SIZE; }
+    void advance_pc_arm();
+    void advance_pc_thumb();
 
-    bool is_flushed = false;
     void flush_pipeline();
 
 #ifdef GDB_DEBUG

include/cpu/thumb/instruction.hh

@@ -251,7 +251,7 @@ struct UnconditionalBranch {
 
 struct LongBranchWithLink {
     uint16_t offset;
-    bool high;
+    bool low;
 };
 
 using InstructionData = std::variant<MoveShiftedRegister,