pith decompile

Two modes, selected by the file extension.

IR mode (.pi input)

pith decompile <file.pi> [more.pi ...]

Prints the generated QBE SSA IL to stdout. Useful for inspecting what the compiler produces:

pith decompile hello.pi

data $str.1 = { w 1, h 3, h 1, w 6, w 5, b "pith", b 0 }
data $str.2 = { w 1, h 3, h 1, w 8, w 7, b "hello, ", b 0 }
data $str.3 = { w 1, h 3, h 1, w 2, w 1, b "!", b 0 }

export function w $main() {
@main.start
    %.v1_name =l alloc8 8
    storel $str.1, %.v1_name
    %.t1 =l loadl %.v1_name
    %.t2 =w call $pith_str_equals(l %.t1, l $str.1)
    jnz %.t2, @L2, @L3
@L2
    %.t3 =l call $pith_str_concat(l $str.2, l %.t1)
    %.t4 =l call $pith_str_concat(l %.t3, l $str.3)
    call $pith_rt_print(l %.t4)
    call $pith_release(l %.t4)
    call $pith_release(l %.t3)
    jmp @L1
@L3
@L1
@main.exit
    ret 0
}

Binary mode (workspace restore)

pith decompile <binary>

Unpacks an embedded debug workspace from a binary built with --embed-source:

1. Open the executable in binary read mode.
2. Seek to SEEK_END - 16.
3. Read the 16-byte PithDebugFooter trailer.
4. Check the magic ("PITHDEBG").
5. Read payload_size, seek backward by 16 + payload_size.
6. Extract the archived files into ./restored_workspace/.

pith decompile ./myapp
# restored workspace successfully extracted to ./restored_workspace/

If the binary has no embedded payload (was built without --embed-source), prints:

error: binary contains no embedded debug workspace payload.

and exits with status 1.

Security

The tar extraction is hardened against:

• Path traversal (../../ components), rejected before any filesystem access
• Absolute paths (/etc/passwd), rejected
• Empty path components (a//b), rejected
• Corrupt headers (missing ustar magic), rejected
• Implausibly huge declared sizes, rejected against the actual buffer
• Truncated blocks, handled gracefully, nothing written