kaizen/src/frontend/Debugger.cpp

#include <Debugger.hpp>
#include <imgui.h>
#include <execution>

void BreakpointFunc(s64 addr, s64 startAddr, Disassembler::DisassemblyResult&) {
  n64::Core& core = n64::Core::GetInstance();
  bool isBroken = core.breakpoints.contains(addr + 4);
  ImGui::PushStyleColor(ImGuiCol_CheckMark, 0xff0000ff);
  ImGui::PushStyleColor(ImGuiCol_FrameBg, 0);
  ImGui::PushStyleColor(ImGuiCol_FrameBgActive, 0);
  ImGui::PushStyleColor(ImGuiCol_FrameBgHovered, 0x800000ff);
  ImGui::PushStyleVar(ImGuiStyleVar_ChildRounding, 0.5f);
  if(ImGui::Checkbox(std::format("##toggleBreakpoint{}", (addr - startAddr) / 4).c_str(), &isBroken)) {
    core.ToggleBreakpoint(addr + 4);
  }
  ImGui::PopStyleVar();
  ImGui::PopStyleColor();
  ImGui::PopStyleColor();
  ImGui::PopStyleColor();
  ImGui::PopStyleColor();
}

void AddressFunc(s64, s64, Disassembler::DisassemblyResult& disasm) {
  if(!disasm.success) {
    ImGui::TextColored(ImColor(0xffeaefb6), "????????????????");
    return;
  }
  
  ImGui::TextColored(ImColor(0xffeaefb6), "%s", std::format("{:016X}:", disasm.address).c_str());
}

void InstructionFunc(s64, s64, Disassembler::DisassemblyResult& disasm) {
  if(!disasm.success) {
    ImGui::TextColored(ImColor(0xffcbf1ae), "Disassembly unsuccessful...");
    return;
  }
  
  ImGui::TextColored(ImColor(0xffcbf1ae), "%s", std::format("{} ", disasm.mnemonic).c_str());
  ImGui::SameLine(0, 0);
  for(int i = 0; i < 3; i++) {
    if(disasm.ops[i].str.empty())
      continue;

    if(i >= 2) {
      ImGui::TextColored(ImColor(disasm.ops[i].color), "%s", disasm.ops[i].str.c_str());
      ImGui::SameLine(0, 0);
      continue;
    }

    std::string op_str = disasm.ops[i].str;
    if(!disasm.ops[i+1].str.empty())
      op_str += ", ";
    
    ImGui::TextColored(ImColor(disasm.ops[i].color), "%s", op_str.c_str());
    ImGui::SameLine(0, 0);
  }
}

void CommentFunc(s64, s64, Disassembler::DisassemblyResult& disasm) {
  n64::Core& core = n64::Core::GetInstance();
  n64::Mem& mem = core.cpu->GetMem();
  n64::Registers& regs = core.cpu->GetRegs();

  if(!disasm.success) {
    ImGui::TextColored(ImColor(0xff71efe5), "");
    return;
  }

  ImGui::TextColored(ImColor(0xff71efe5), "%s", std::format("{}", disasm.GetFormattedComment()).c_str());

  u64 vaddr = disasm.GetResolvedAddressFromComment();

  if(vaddr == 0xFFFF'FFFF'FFFF'FFFFull)
    return;

  if(!ImGui::IsItemHovered(ImGuiHoveredFlags_DelayNormal | ImGuiHoveredFlags_ForTooltip))
    return;

  if(!ImGui::BeginTooltip())
    return;
  
  ImGui::Text("%s", std::format("Memory contents @ 0x{:016X}", vaddr).c_str());
  if(!ImGui::BeginTable("##memoryContents", 16))
    return;
  
  for(u32 col = 0; col < 16; col++)
    ImGui::TableSetupColumn(std::format("##hexCol{}", col).c_str());

  ImGui::TableHeadersRow();

  for(u32 row = 0; row < 16; row++) {
    ImGui::TableNextRow();
    for(u32 col = 0; col < 16; col+=4) {
      u32 paddr;
      if(!regs.cop0.MapVAddr(n64::Cop0::LOAD, vaddr+row*0x10+col, paddr))
        continue;
      
      u32 val = mem.Read<u32>(paddr);

      ImGui::TableSetColumnIndex(col+0);
      ImGui::Text("%02X", (val >> 24) & 0xff);
      ImGui::TableSetColumnIndex(col+1);
      ImGui::Text("%02X", (val >> 16) & 0xff);
      ImGui::TableSetColumnIndex(col+2);
      ImGui::Text("%02X", (val >>  8) & 0xff);
      ImGui::TableSetColumnIndex(col+3);
      ImGui::Text("%02X", (val >>  0) & 0xff);
    }
  }
  
  ImGui::EndTable();
  ImGui::EndTooltip();
}

bool Debugger::render() {
  n64::Core& core = n64::Core::GetInstance();
  n64::Registers& regs = core.cpu->GetRegs();

  if(!enabled)
    return false;

  static s64 startAddr = 0xFFFF'FFFF'8000'0000;
  int step = 4, stepFast = 256;
  static bool followPC = true;
  
  if(!ImGui::Begin("Debugger", &enabled))
    return false;

  ImGui::BeginDisabled(followPC);
  ImGui::InputScalar("Address", ImGuiDataType_S64, (void*)&startAddr, (void*)&step, (void*)&stepFast, "%016lX", ImGuiInputTextFlags_CharsHexadecimal);
  ImGui::EndDisabled();

  ImGui::Text("Follow program counter:");
  ImGui::SameLine(0,0);

  ImGui::Checkbox("##followPC", &followPC);
  ImGui::SameLine(0,0);

  ImGui::Text("Add a breakpoint");
  ImGui::SameLine(0,0);

  if(followPC)
    startAddr = regs.pc - 256; // TODO: arbitrary???

  if(ImGui::Button(core.breakpoints.contains(startAddr) ? "-" : "+")) {
    core.ToggleBreakpoint(startAddr);
  }

  if(!ImGui::BeginTable("Disassembly", columns.size(), ImGuiTableFlags_SizingStretchSame | ImGuiTableFlags_Resizable | ImGuiTableFlags_BordersOuter | ImGuiTableFlags_BordersV | ImGuiTableFlags_ContextMenuInBody))
    return false;

  for(int i = 0; i < columns.size(); i++)
    ImGui::TableSetupColumn(columns[i].name);
  
  ImGui::TableHeadersRow();

  for(u64 addr = startAddr; addr < startAddr + MAX_LINES_OF_DISASM * sizeof(u32); addr += sizeof(u32)) {
    auto disasm = Disassembler::GetInstance().Disassemble(addr);
    auto addrIsCurrent = addr == regs.nextPC;
    auto addrIsBreakpoint = core.breakpoints.contains(addr);
    ImColor colorChoice = ImGui::GetStyle().Colors[ImGuiCol_TableRowBg];
    ImColor colorChoiceAlt = ImGui::GetStyle().Colors[ImGuiCol_TableRowBgAlt];
    if(addrIsCurrent) {
      colorChoice = 0x80e27fbc;
      colorChoiceAlt = 0x80e27fbc;
    }

    if(addrIsBreakpoint) {
      colorChoice = 0x800000ff;
      colorChoiceAlt = 0x800000ff;
    }

    ImGui::PushStyleColor(ImGuiCol_TableRowBg, colorChoice.Value);
    ImGui::PushStyleColor(ImGuiCol_TableRowBgAlt, colorChoiceAlt.Value);

    ImGui::TableNextRow();
    for(int i = 0; i < columns.size(); i++) {
      ImGui::TableSetColumnIndex(i);
      columns[i].func(addr, startAddr, disasm);
    }

    ImGui::PopStyleColor();
    ImGui::PopStyleColor();
  }

  ImGui::EndTable();

  ImGui::End();

  return true;
}