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authoruvok2026-01-11 10:14:34 +0100
committeruvok2026-01-11 10:14:34 +0100
commit0f86e4c661fa3164447a77d84610146426008364 (patch)
tree42cc3deb698fd4f77abcddb4aff6d99cb69859e6 /nandgame/assembler/disas.cpp
parent34ac7a712f62d67372c2d293c3dfc27c476f90a4 (diff)
Reorganize cpp files
Diffstat (limited to 'nandgame/assembler/disas.cpp')
-rw-r--r--nandgame/assembler/disas.cpp194
1 files changed, 0 insertions, 194 deletions
diff --git a/nandgame/assembler/disas.cpp b/nandgame/assembler/disas.cpp
deleted file mode 100644
index ac7ca0c..0000000
--- a/nandgame/assembler/disas.cpp
+++ /dev/null
@@ -1,194 +0,0 @@
-// LLM converted. Here be dragons.
-
-#include "disas.h"
-
-#include <string>
-#include <vector>
-#include <sstream>
-#include <iomanip>
-
-static const std::string ZERO = "#0";
-static const std::string DEST_NONE = "_";
-static const std::string JUMP_NONE = "";
-
-static const std::vector<std::string> JUMPS_IF_NZERO = {"jgt", "jlt", "jne", "jmp"};
-static const std::vector<std::string> JUMPS_IF_ZERO = {"jge", "jle", "jeq", "jmp"};
-
-struct Decoded {
- std::string mnemonic;
- std::string dest;
- std::string op1;
- std::string op2;
- std::string jumpdest;
-};
-
-static bool in_list(const std::string &s, const std::vector<std::string> &v) {
- for (const auto &x : v) {
- if (x == s) return true;
- }
- return false;
-}
-
-static std::string decode_jump(uint16_t ins) {
- if ((ins & 0x7) == 0) {
- return JUMP_NONE;
- }
-
- if ((ins & 0x7) == 0x7) {
- return "jmp";
- }
-
- bool jl = (ins & (1 << 2)) != 0;
- bool je = (ins & (1 << 1)) != 0;
- bool jg = (ins & (1 << 0)) != 0;
-
- if (jl && je) {
- return "jle";
- }
- if (jl && jg) {
- return "jne";
- }
- if (je && jg) {
- return "jge";
- }
-
- if (jl) return "jlt";
- if (je) return "jeq";
- if (jg) return "jgt";
-
- return "<unknown>";
-}
-
-static std::pair<std::string, bool> decode_ins(uint16_t ins) {
- int opcode = (ins >> 8) & 0x03;
- bool ar_n_log = (ins & (1 << 10)) != 0;
- opcode |= (ar_n_log ? 1 : 0) << 2;
-
- switch (opcode) {
- case 0b000: return {"and", true};
- case 0b001: return {"or", true};
- case 0b010: return {"xor", true};
- case 0b011: return {"not", false};
- case 0b100: return {"add", true};
- case 0b101: return {"inc", false};
- case 0b110: return {"sub", true};
- case 0b111: return {"dec", false};
- default: return {"<?>", false};
- }
-}
-
-static std::string decode_arg1(uint16_t ins) {
- bool use_mem = (ins & (1 << 12)) != 0;
- bool zx = (ins & (1 << 7)) != 0;
- bool sw = (ins & (1 << 6)) != 0;
-
- if (zx) return ZERO;
- if (!sw) return "D";
- return use_mem ? "M" : "A";
-}
-
-static std::string decode_arg2(uint16_t ins) {
- bool use_mem = (ins & (1 << 12)) != 0;
- bool sw = (ins & (1 << 6)) != 0;
-
- if (sw) return "D";
- return use_mem ? "M" : "A";
-}
-
-static std::string decode_dest(uint16_t ins) {
- bool dA = (ins & (1 << 5)) != 0;
- bool dD = (ins & (1 << 4)) != 0;
- bool dM = (ins & (1 << 3)) != 0;
-
- std::string dest;
- if (dA) dest += "A";
- if (dD) dest += "D";
- if (dM) dest += "M";
-
- return dest.empty() ? DEST_NONE : dest;
-}
-
-static Decoded decode_instruction(uint16_t ins) {
- if ((ins & 0x8000) == 0) {
- return {"mov", "A", "#" + std::to_string(ins), "", ""};
- } else {
- auto [mnemonic, two_op] = decode_ins(ins);
- std::string dest = decode_dest(ins);
- std::string op1 = decode_arg1(ins);
- std::string op2 = two_op ? decode_arg2(ins) : "";
- std::string jumpdst = decode_jump(ins);
- return {mnemonic, dest, op1, op2, jumpdst};
- }
-}
-
-static Decoded fixup_ins(uint16_t ins) {
- Decoded d = decode_instruction(ins);
- std::string &mnemonic = d.mnemonic;
- std::string &dest = d.dest;
- std::string &op1 = d.op1;
- std::string &op2 = d.op2;
- std::string &jumpdest = d.jumpdest;
-
- if (op1 == ZERO) {
- if (mnemonic == "sub") {
- return {"neg", dest, op2, "", jumpdest};
- }
-
- if (mnemonic == "and") {
- if (dest == DEST_NONE) {
- if (in_list(jumpdest, JUMPS_IF_ZERO)) {
- return {"jmp", "", "", "", ""};
- } else {
- return {"nop", "", "", "", ""};
- }
- } else {
- std::string newjmp = in_list(jumpdest, JUMPS_IF_ZERO) ? "jmp" : "";
- return {"mov", dest, ZERO, "", newjmp};
- }
- }
-
- if (mnemonic == "add" || mnemonic == "or" || mnemonic == "xor") {
- if (dest == DEST_NONE && jumpdest == JUMP_NONE) {
- return {"nop", "", "", "", ""};
- } else {
- return {"mov", dest, op2, "", jumpdest};
- }
- }
-
- if (mnemonic == "not") {
- if (dest == DEST_NONE) {
- if (jumpdest == "jeq" || jumpdest == "jgt" ||
- jumpdest == "jge" || jumpdest == JUMP_NONE) {
- return {"nop", "", "", "", ""};
- } else {
- return {"jmp", "", "", "", ""};
- }
- }
- }
- }
-
- return d;
-}
-
-std::string print_decoded(uint16_t ins, bool simplify) {
- // illegal instruction
- if ((ins & 0xC000) == 0x8000)
- return "halt";
-
- Decoded d = simplify ? fixup_ins(ins) : decode_instruction(ins);
-
- std::string jumpdest_str = d.jumpdest.empty() ? "" : "." + d.jumpdest;
- std::string opcode_str = d.mnemonic + jumpdest_str;
- std::string dest_str = d.dest.empty() ? std::string(7, ' ')
- : d.dest + ", ";
- std::string op2_str = d.op2.empty() ? "" : ", ";
- std::string op1_str = d.op1 + op2_str;
-
- std::ostringstream oss;
- oss << std::left << std::setw(9) << opcode_str
- << std::setw(6) << dest_str
- << std::setw(4) << op1_str
- << d.op2;
-
- return oss.str();
-}