LLVM-MC(1)

💖 NAME 💖

llvm-mc — bestie, this is the manual page for llvm-mc 14, and it lives in the User Commands section of the manual. Come sit with me, we're gonna read it together and it's gonna be iconic. 🫶

---

🌈 DESCRIPTION 🌈

OVERVIEW: llvm machine code playground 🛝✨

USAGE:

llvm-mc [options] <input file>

OPTIONS:

---

🎀 Color Options 🎀

• --color — turns on colors in the output. The default is autodetect, so it just vibes and figures out whether your terminal can handle the sparkle. 💅

---

✨ Generic Options ✨

• --help — shows you all the available options. Want even more? There's --help-hidden for the extra secret ones. 🙈
• --help-list — prints out the list of available options. And yeah, there's --help-list-hidden if you want the hidden list too. 👀
• --version — shows you the version of this program. That's it, that's the whole job. ⭐

---

🔥 MC Options 🔥

• -I=<directory> — directory where the include files live. 📁
• -M=<string> — disassembler options. 🧚
• --arch=<string> — the target arch you're assembling for. Not sure which ones exist? Peek at -version for the available targets. 🏗️

🎬 Action to perform 🎬

• --as-lex — lex tokens out of a .s file. 🔤
• --assemble — assemble a .s file. This one is the default, so it's the main character. 👑
• --disassemble — disassemble strings of hex bytes. 🔍
• --mdis — marked up disassembly of strings of hex bytes. ✨

🗜️ And the rest of the MC options 🗜️

• --compress-debug-sections=<value> — choose how DWARF debug sections get compressed:
  • =none — no compression at all, just raw.
  • =zlib — use zlib compression.
  • =zlib-gnu — use zlib-gnu compression. ⚠️ This one is deprecated, so, like, know that going in.
• --defsym=<string> — defines a symbol to be an integer constant. 🔢
• --fdebug-compilation-dir=<string> — specifies the debug info's compilation dir. 🗂️
• --fdebug-prefix-map=<= separated key-value pairs> — maps file source paths in debug info. 🗺️
• --filetype=<value> — choose an output file type:
  • =asm — emit an assembly (.s) file.
  • =null — don't emit anything. It's for timing purposes, not for results. 🕐
  • =obj — emit a native object (.o) file.
• -g — generate dwarf debugging info for assembly source files. 🐛
• --large-code-model — creates cfi directives that assume the code might be more than 2gb away. Yes, 2gb. Big girl energy. 💪
• --main-file-name=<string> — specifies the name we should consider the input file. 🏷️
• --masm-hexfloats — enables MASM-style hex float initializers, like 3F800000r. 🌸
• --masm-integers — enables binary and hex masm integers, like 0b110 and 0ABCh. 🍓
• --mattr=<a1,+a2,-a3,...> — target specific attributes. Hit up -mattr=help for the details. 🎛️
• --mcpu=<cpu-name> — target a specific cpu type. Same deal, -mcpu=help has the details. 🧠
• --motorola-integers — enables binary and hex Motorola integers, like %110 and $ABC. 🏁
• -n — don't assume the assembly file starts in the text section. 🙅
• --no-exec-stack — this file doesn't need an exec stack. 🚫
• -o=<filename> — output filename. 💾
• --output-asm-variant=<uint> — which syntax variant to use for output printing. 🎨
• --position-independent — position independent. 📍
• --preserve-comments — preserves comments in the outputted assembly. 😭 (we love a comment that survives)
• --print-imm-hex — prefers hex format for immediate values. 🔡
• --relax-relocations — emits R_X86_64_GOTPCRELX instead of R_X86_64_GOTPCREL. 🔄
• --save-temp-labels — doesn't discard temporary labels. 💾
• --show-encoding — shows instruction encodings. 🔬
• --show-inst — shows the internal instruction representation. 🫧
• --show-inst-operands — shows instruction operands as parsed. 🧩
• --split-dwarf-file=<filename> — DWO output filename. 🌼
• --triple=<string> — the target triple you're assembling for. Again, -version lists the available targets. 🎯

---

ok bestie that's the whole page, every single option accounted for, no cap. now go forth and assemble something gorgeous. 💅✨

llvm-mc 14 · May 2025 · LLVM-MC(1) — mwah, love u, bye! 🎀🦋💜